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authorroot <root@artemis.panaceas.org>2015-12-25 04:40:36 +0000
committerroot <root@artemis.panaceas.org>2015-12-25 04:40:36 +0000
commit849369d6c66d3054688672f97d31fceb8e8230fb (patch)
tree6135abc790ca67dedbe07c39806591e70eda81ce /security/keys
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initial_commit
Diffstat (limited to 'security/keys')
-rw-r--r--security/keys/Makefile20
-rw-r--r--security/keys/compat.c141
-rw-r--r--security/keys/encrypted.c902
-rw-r--r--security/keys/encrypted.h54
-rw-r--r--security/keys/gc.c222
-rw-r--r--security/keys/internal.h246
-rw-r--r--security/keys/key.c1118
-rw-r--r--security/keys/keyctl.c1629
-rw-r--r--security/keys/keyring.c1226
-rw-r--r--security/keys/permission.c118
-rw-r--r--security/keys/proc.c352
-rw-r--r--security/keys/process_keys.c867
-rw-r--r--security/keys/request_key.c713
-rw-r--r--security/keys/request_key_auth.c265
-rw-r--r--security/keys/sysctl.c65
-rw-r--r--security/keys/trusted.c1180
-rw-r--r--security/keys/trusted.h134
-rw-r--r--security/keys/user_defined.c191
18 files changed, 9443 insertions, 0 deletions
diff --git a/security/keys/Makefile b/security/keys/Makefile
new file mode 100644
index 00000000..1bf090a8
--- /dev/null
+++ b/security/keys/Makefile
@@ -0,0 +1,20 @@
+#
+# Makefile for key management
+#
+
+obj-y := \
+ gc.o \
+ key.o \
+ keyring.o \
+ keyctl.o \
+ permission.o \
+ process_keys.o \
+ request_key.o \
+ request_key_auth.o \
+ user_defined.o
+
+obj-$(CONFIG_TRUSTED_KEYS) += trusted.o
+obj-$(CONFIG_ENCRYPTED_KEYS) += encrypted.o
+obj-$(CONFIG_KEYS_COMPAT) += compat.o
+obj-$(CONFIG_PROC_FS) += proc.o
+obj-$(CONFIG_SYSCTL) += sysctl.o
diff --git a/security/keys/compat.c b/security/keys/compat.c
new file mode 100644
index 00000000..338b510e
--- /dev/null
+++ b/security/keys/compat.c
@@ -0,0 +1,141 @@
+/* 32-bit compatibility syscall for 64-bit systems
+ *
+ * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/syscalls.h>
+#include <linux/keyctl.h>
+#include <linux/compat.h>
+#include <linux/slab.h>
+#include "internal.h"
+
+/*
+ * Instantiate a key with the specified compatibility multipart payload and
+ * link the key into the destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority). No other permissions are required.
+ *
+ * If successful, 0 will be returned.
+ */
+long compat_keyctl_instantiate_key_iov(
+ key_serial_t id,
+ const struct compat_iovec __user *_payload_iov,
+ unsigned ioc,
+ key_serial_t ringid)
+{
+ struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
+ long ret;
+
+ if (_payload_iov == 0 || ioc == 0)
+ goto no_payload;
+
+ ret = compat_rw_copy_check_uvector(WRITE, _payload_iov, ioc,
+ ARRAY_SIZE(iovstack),
+ iovstack, &iov);
+ if (ret < 0)
+ return ret;
+ if (ret == 0)
+ goto no_payload_free;
+
+ ret = keyctl_instantiate_key_common(id, iov, ioc, ret, ringid);
+
+ if (iov != iovstack)
+ kfree(iov);
+ return ret;
+
+no_payload_free:
+ if (iov != iovstack)
+ kfree(iov);
+no_payload:
+ return keyctl_instantiate_key_common(id, NULL, 0, 0, ringid);
+}
+
+/*
+ * The key control system call, 32-bit compatibility version for 64-bit archs
+ *
+ * This should only be called if the 64-bit arch uses weird pointers in 32-bit
+ * mode or doesn't guarantee that the top 32-bits of the argument registers on
+ * taking a 32-bit syscall are zero. If you can, you should call sys_keyctl()
+ * directly.
+ */
+asmlinkage long compat_sys_keyctl(u32 option,
+ u32 arg2, u32 arg3, u32 arg4, u32 arg5)
+{
+ switch (option) {
+ case KEYCTL_GET_KEYRING_ID:
+ return keyctl_get_keyring_ID(arg2, arg3);
+
+ case KEYCTL_JOIN_SESSION_KEYRING:
+ return keyctl_join_session_keyring(compat_ptr(arg2));
+
+ case KEYCTL_UPDATE:
+ return keyctl_update_key(arg2, compat_ptr(arg3), arg4);
+
+ case KEYCTL_REVOKE:
+ return keyctl_revoke_key(arg2);
+
+ case KEYCTL_DESCRIBE:
+ return keyctl_describe_key(arg2, compat_ptr(arg3), arg4);
+
+ case KEYCTL_CLEAR:
+ return keyctl_keyring_clear(arg2);
+
+ case KEYCTL_LINK:
+ return keyctl_keyring_link(arg2, arg3);
+
+ case KEYCTL_UNLINK:
+ return keyctl_keyring_unlink(arg2, arg3);
+
+ case KEYCTL_SEARCH:
+ return keyctl_keyring_search(arg2, compat_ptr(arg3),
+ compat_ptr(arg4), arg5);
+
+ case KEYCTL_READ:
+ return keyctl_read_key(arg2, compat_ptr(arg3), arg4);
+
+ case KEYCTL_CHOWN:
+ return keyctl_chown_key(arg2, arg3, arg4);
+
+ case KEYCTL_SETPERM:
+ return keyctl_setperm_key(arg2, arg3);
+
+ case KEYCTL_INSTANTIATE:
+ return keyctl_instantiate_key(arg2, compat_ptr(arg3), arg4,
+ arg5);
+
+ case KEYCTL_NEGATE:
+ return keyctl_negate_key(arg2, arg3, arg4);
+
+ case KEYCTL_SET_REQKEY_KEYRING:
+ return keyctl_set_reqkey_keyring(arg2);
+
+ case KEYCTL_SET_TIMEOUT:
+ return keyctl_set_timeout(arg2, arg3);
+
+ case KEYCTL_ASSUME_AUTHORITY:
+ return keyctl_assume_authority(arg2);
+
+ case KEYCTL_GET_SECURITY:
+ return keyctl_get_security(arg2, compat_ptr(arg3), arg4);
+
+ case KEYCTL_SESSION_TO_PARENT:
+ return keyctl_session_to_parent();
+
+ case KEYCTL_REJECT:
+ return keyctl_reject_key(arg2, arg3, arg4, arg5);
+
+ case KEYCTL_INSTANTIATE_IOV:
+ return compat_keyctl_instantiate_key_iov(
+ arg2, compat_ptr(arg3), arg4, arg5);
+
+ default:
+ return -EOPNOTSUPP;
+ }
+}
diff --git a/security/keys/encrypted.c b/security/keys/encrypted.c
new file mode 100644
index 00000000..b1cba5bf
--- /dev/null
+++ b/security/keys/encrypted.c
@@ -0,0 +1,902 @@
+/*
+ * Copyright (C) 2010 IBM Corporation
+ *
+ * Author:
+ * Mimi Zohar <zohar@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * See Documentation/security/keys-trusted-encrypted.txt
+ */
+
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/parser.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <keys/user-type.h>
+#include <keys/trusted-type.h>
+#include <keys/encrypted-type.h>
+#include <linux/key-type.h>
+#include <linux/random.h>
+#include <linux/rcupdate.h>
+#include <linux/scatterlist.h>
+#include <linux/crypto.h>
+#include <crypto/hash.h>
+#include <crypto/sha.h>
+#include <crypto/aes.h>
+
+#include "encrypted.h"
+
+static const char KEY_TRUSTED_PREFIX[] = "trusted:";
+static const char KEY_USER_PREFIX[] = "user:";
+static const char hash_alg[] = "sha256";
+static const char hmac_alg[] = "hmac(sha256)";
+static const char blkcipher_alg[] = "cbc(aes)";
+static unsigned int ivsize;
+static int blksize;
+
+#define KEY_TRUSTED_PREFIX_LEN (sizeof (KEY_TRUSTED_PREFIX) - 1)
+#define KEY_USER_PREFIX_LEN (sizeof (KEY_USER_PREFIX) - 1)
+#define HASH_SIZE SHA256_DIGEST_SIZE
+#define MAX_DATA_SIZE 4096
+#define MIN_DATA_SIZE 20
+
+struct sdesc {
+ struct shash_desc shash;
+ char ctx[];
+};
+
+static struct crypto_shash *hashalg;
+static struct crypto_shash *hmacalg;
+
+enum {
+ Opt_err = -1, Opt_new, Opt_load, Opt_update
+};
+
+static const match_table_t key_tokens = {
+ {Opt_new, "new"},
+ {Opt_load, "load"},
+ {Opt_update, "update"},
+ {Opt_err, NULL}
+};
+
+static int aes_get_sizes(void)
+{
+ struct crypto_blkcipher *tfm;
+
+ tfm = crypto_alloc_blkcipher(blkcipher_alg, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(tfm)) {
+ pr_err("encrypted_key: failed to alloc_cipher (%ld)\n",
+ PTR_ERR(tfm));
+ return PTR_ERR(tfm);
+ }
+ ivsize = crypto_blkcipher_ivsize(tfm);
+ blksize = crypto_blkcipher_blocksize(tfm);
+ crypto_free_blkcipher(tfm);
+ return 0;
+}
+
+/*
+ * valid_master_desc - verify the 'key-type:desc' of a new/updated master-key
+ *
+ * key-type:= "trusted:" | "encrypted:"
+ * desc:= master-key description
+ *
+ * Verify that 'key-type' is valid and that 'desc' exists. On key update,
+ * only the master key description is permitted to change, not the key-type.
+ * The key-type remains constant.
+ *
+ * On success returns 0, otherwise -EINVAL.
+ */
+static int valid_master_desc(const char *new_desc, const char *orig_desc)
+{
+ if (!memcmp(new_desc, KEY_TRUSTED_PREFIX, KEY_TRUSTED_PREFIX_LEN)) {
+ if (strlen(new_desc) == KEY_TRUSTED_PREFIX_LEN)
+ goto out;
+ if (orig_desc)
+ if (memcmp(new_desc, orig_desc, KEY_TRUSTED_PREFIX_LEN))
+ goto out;
+ } else if (!memcmp(new_desc, KEY_USER_PREFIX, KEY_USER_PREFIX_LEN)) {
+ if (strlen(new_desc) == KEY_USER_PREFIX_LEN)
+ goto out;
+ if (orig_desc)
+ if (memcmp(new_desc, orig_desc, KEY_USER_PREFIX_LEN))
+ goto out;
+ } else
+ goto out;
+ return 0;
+out:
+ return -EINVAL;
+}
+
+/*
+ * datablob_parse - parse the keyctl data
+ *
+ * datablob format:
+ * new <master-key name> <decrypted data length>
+ * load <master-key name> <decrypted data length> <encrypted iv + data>
+ * update <new-master-key name>
+ *
+ * Tokenizes a copy of the keyctl data, returning a pointer to each token,
+ * which is null terminated.
+ *
+ * On success returns 0, otherwise -EINVAL.
+ */
+static int datablob_parse(char *datablob, char **master_desc,
+ char **decrypted_datalen, char **hex_encoded_iv)
+{
+ substring_t args[MAX_OPT_ARGS];
+ int ret = -EINVAL;
+ int key_cmd;
+ char *p;
+
+ p = strsep(&datablob, " \t");
+ if (!p)
+ return ret;
+ key_cmd = match_token(p, key_tokens, args);
+
+ *master_desc = strsep(&datablob, " \t");
+ if (!*master_desc)
+ goto out;
+
+ if (valid_master_desc(*master_desc, NULL) < 0)
+ goto out;
+
+ if (decrypted_datalen) {
+ *decrypted_datalen = strsep(&datablob, " \t");
+ if (!*decrypted_datalen)
+ goto out;
+ }
+
+ switch (key_cmd) {
+ case Opt_new:
+ if (!decrypted_datalen)
+ break;
+ ret = 0;
+ break;
+ case Opt_load:
+ if (!decrypted_datalen)
+ break;
+ *hex_encoded_iv = strsep(&datablob, " \t");
+ if (!*hex_encoded_iv)
+ break;
+ ret = 0;
+ break;
+ case Opt_update:
+ if (decrypted_datalen)
+ break;
+ ret = 0;
+ break;
+ case Opt_err:
+ break;
+ }
+out:
+ return ret;
+}
+
+/*
+ * datablob_format - format as an ascii string, before copying to userspace
+ */
+static char *datablob_format(struct encrypted_key_payload *epayload,
+ size_t asciiblob_len)
+{
+ char *ascii_buf, *bufp;
+ u8 *iv = epayload->iv;
+ int len;
+ int i;
+
+ ascii_buf = kmalloc(asciiblob_len + 1, GFP_KERNEL);
+ if (!ascii_buf)
+ goto out;
+
+ ascii_buf[asciiblob_len] = '\0';
+
+ /* copy datablob master_desc and datalen strings */
+ len = sprintf(ascii_buf, "%s %s ", epayload->master_desc,
+ epayload->datalen);
+
+ /* convert the hex encoded iv, encrypted-data and HMAC to ascii */
+ bufp = &ascii_buf[len];
+ for (i = 0; i < (asciiblob_len - len) / 2; i++)
+ bufp = pack_hex_byte(bufp, iv[i]);
+out:
+ return ascii_buf;
+}
+
+/*
+ * request_trusted_key - request the trusted key
+ *
+ * Trusted keys are sealed to PCRs and other metadata. Although userspace
+ * manages both trusted/encrypted key-types, like the encrypted key type
+ * data, trusted key type data is not visible decrypted from userspace.
+ */
+static struct key *request_trusted_key(const char *trusted_desc,
+ u8 **master_key, size_t *master_keylen)
+{
+ struct trusted_key_payload *tpayload;
+ struct key *tkey;
+
+ tkey = request_key(&key_type_trusted, trusted_desc, NULL);
+ if (IS_ERR(tkey))
+ goto error;
+
+ down_read(&tkey->sem);
+ tpayload = rcu_dereference(tkey->payload.data);
+ *master_key = tpayload->key;
+ *master_keylen = tpayload->key_len;
+error:
+ return tkey;
+}
+
+/*
+ * request_user_key - request the user key
+ *
+ * Use a user provided key to encrypt/decrypt an encrypted-key.
+ */
+static struct key *request_user_key(const char *master_desc, u8 **master_key,
+ size_t *master_keylen)
+{
+ struct user_key_payload *upayload;
+ struct key *ukey;
+
+ ukey = request_key(&key_type_user, master_desc, NULL);
+ if (IS_ERR(ukey))
+ goto error;
+
+ down_read(&ukey->sem);
+ upayload = rcu_dereference(ukey->payload.data);
+ *master_key = upayload->data;
+ *master_keylen = upayload->datalen;
+error:
+ return ukey;
+}
+
+static struct sdesc *alloc_sdesc(struct crypto_shash *alg)
+{
+ struct sdesc *sdesc;
+ int size;
+
+ size = sizeof(struct shash_desc) + crypto_shash_descsize(alg);
+ sdesc = kmalloc(size, GFP_KERNEL);
+ if (!sdesc)
+ return ERR_PTR(-ENOMEM);
+ sdesc->shash.tfm = alg;
+ sdesc->shash.flags = 0x0;
+ return sdesc;
+}
+
+static int calc_hmac(u8 *digest, const u8 *key, unsigned int keylen,
+ const u8 *buf, unsigned int buflen)
+{
+ struct sdesc *sdesc;
+ int ret;
+
+ sdesc = alloc_sdesc(hmacalg);
+ if (IS_ERR(sdesc)) {
+ pr_info("encrypted_key: can't alloc %s\n", hmac_alg);
+ return PTR_ERR(sdesc);
+ }
+
+ ret = crypto_shash_setkey(hmacalg, key, keylen);
+ if (!ret)
+ ret = crypto_shash_digest(&sdesc->shash, buf, buflen, digest);
+ kfree(sdesc);
+ return ret;
+}
+
+static int calc_hash(u8 *digest, const u8 *buf, unsigned int buflen)
+{
+ struct sdesc *sdesc;
+ int ret;
+
+ sdesc = alloc_sdesc(hashalg);
+ if (IS_ERR(sdesc)) {
+ pr_info("encrypted_key: can't alloc %s\n", hash_alg);
+ return PTR_ERR(sdesc);
+ }
+
+ ret = crypto_shash_digest(&sdesc->shash, buf, buflen, digest);
+ kfree(sdesc);
+ return ret;
+}
+
+enum derived_key_type { ENC_KEY, AUTH_KEY };
+
+/* Derive authentication/encryption key from trusted key */
+static int get_derived_key(u8 *derived_key, enum derived_key_type key_type,
+ const u8 *master_key, size_t master_keylen)
+{
+ u8 *derived_buf;
+ unsigned int derived_buf_len;
+ int ret;
+
+ derived_buf_len = strlen("AUTH_KEY") + 1 + master_keylen;
+ if (derived_buf_len < HASH_SIZE)
+ derived_buf_len = HASH_SIZE;
+
+ derived_buf = kzalloc(derived_buf_len, GFP_KERNEL);
+ if (!derived_buf) {
+ pr_err("encrypted_key: out of memory\n");
+ return -ENOMEM;
+ }
+ if (key_type)
+ strcpy(derived_buf, "AUTH_KEY");
+ else
+ strcpy(derived_buf, "ENC_KEY");
+
+ memcpy(derived_buf + strlen(derived_buf) + 1, master_key,
+ master_keylen);
+ ret = calc_hash(derived_key, derived_buf, derived_buf_len);
+ kfree(derived_buf);
+ return ret;
+}
+
+static int init_blkcipher_desc(struct blkcipher_desc *desc, const u8 *key,
+ unsigned int key_len, const u8 *iv,
+ unsigned int ivsize)
+{
+ int ret;
+
+ desc->tfm = crypto_alloc_blkcipher(blkcipher_alg, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(desc->tfm)) {
+ pr_err("encrypted_key: failed to load %s transform (%ld)\n",
+ blkcipher_alg, PTR_ERR(desc->tfm));
+ return PTR_ERR(desc->tfm);
+ }
+ desc->flags = 0;
+
+ ret = crypto_blkcipher_setkey(desc->tfm, key, key_len);
+ if (ret < 0) {
+ pr_err("encrypted_key: failed to setkey (%d)\n", ret);
+ crypto_free_blkcipher(desc->tfm);
+ return ret;
+ }
+ crypto_blkcipher_set_iv(desc->tfm, iv, ivsize);
+ return 0;
+}
+
+static struct key *request_master_key(struct encrypted_key_payload *epayload,
+ u8 **master_key, size_t *master_keylen)
+{
+ struct key *mkey = NULL;
+
+ if (!strncmp(epayload->master_desc, KEY_TRUSTED_PREFIX,
+ KEY_TRUSTED_PREFIX_LEN)) {
+ mkey = request_trusted_key(epayload->master_desc +
+ KEY_TRUSTED_PREFIX_LEN,
+ master_key, master_keylen);
+ } else if (!strncmp(epayload->master_desc, KEY_USER_PREFIX,
+ KEY_USER_PREFIX_LEN)) {
+ mkey = request_user_key(epayload->master_desc +
+ KEY_USER_PREFIX_LEN,
+ master_key, master_keylen);
+ } else
+ goto out;
+
+ if (IS_ERR(mkey))
+ pr_info("encrypted_key: key %s not found",
+ epayload->master_desc);
+ if (mkey)
+ dump_master_key(*master_key, *master_keylen);
+out:
+ return mkey;
+}
+
+/* Before returning data to userspace, encrypt decrypted data. */
+static int derived_key_encrypt(struct encrypted_key_payload *epayload,
+ const u8 *derived_key,
+ unsigned int derived_keylen)
+{
+ struct scatterlist sg_in[2];
+ struct scatterlist sg_out[1];
+ struct blkcipher_desc desc;
+ unsigned int encrypted_datalen;
+ unsigned int padlen;
+ char pad[16];
+ int ret;
+
+ encrypted_datalen = roundup(epayload->decrypted_datalen, blksize);
+ padlen = encrypted_datalen - epayload->decrypted_datalen;
+
+ ret = init_blkcipher_desc(&desc, derived_key, derived_keylen,
+ epayload->iv, ivsize);
+ if (ret < 0)
+ goto out;
+ dump_decrypted_data(epayload);
+
+ memset(pad, 0, sizeof pad);
+ sg_init_table(sg_in, 2);
+ sg_set_buf(&sg_in[0], epayload->decrypted_data,
+ epayload->decrypted_datalen);
+ sg_set_buf(&sg_in[1], pad, padlen);
+
+ sg_init_table(sg_out, 1);
+ sg_set_buf(sg_out, epayload->encrypted_data, encrypted_datalen);
+
+ ret = crypto_blkcipher_encrypt(&desc, sg_out, sg_in, encrypted_datalen);
+ crypto_free_blkcipher(desc.tfm);
+ if (ret < 0)
+ pr_err("encrypted_key: failed to encrypt (%d)\n", ret);
+ else
+ dump_encrypted_data(epayload, encrypted_datalen);
+out:
+ return ret;
+}
+
+static int datablob_hmac_append(struct encrypted_key_payload *epayload,
+ const u8 *master_key, size_t master_keylen)
+{
+ u8 derived_key[HASH_SIZE];
+ u8 *digest;
+ int ret;
+
+ ret = get_derived_key(derived_key, AUTH_KEY, master_key, master_keylen);
+ if (ret < 0)
+ goto out;
+
+ digest = epayload->master_desc + epayload->datablob_len;
+ ret = calc_hmac(digest, derived_key, sizeof derived_key,
+ epayload->master_desc, epayload->datablob_len);
+ if (!ret)
+ dump_hmac(NULL, digest, HASH_SIZE);
+out:
+ return ret;
+}
+
+/* verify HMAC before decrypting encrypted key */
+static int datablob_hmac_verify(struct encrypted_key_payload *epayload,
+ const u8 *master_key, size_t master_keylen)
+{
+ u8 derived_key[HASH_SIZE];
+ u8 digest[HASH_SIZE];
+ int ret;
+
+ ret = get_derived_key(derived_key, AUTH_KEY, master_key, master_keylen);
+ if (ret < 0)
+ goto out;
+
+ ret = calc_hmac(digest, derived_key, sizeof derived_key,
+ epayload->master_desc, epayload->datablob_len);
+ if (ret < 0)
+ goto out;
+ ret = memcmp(digest, epayload->master_desc + epayload->datablob_len,
+ sizeof digest);
+ if (ret) {
+ ret = -EINVAL;
+ dump_hmac("datablob",
+ epayload->master_desc + epayload->datablob_len,
+ HASH_SIZE);
+ dump_hmac("calc", digest, HASH_SIZE);
+ }
+out:
+ return ret;
+}
+
+static int derived_key_decrypt(struct encrypted_key_payload *epayload,
+ const u8 *derived_key,
+ unsigned int derived_keylen)
+{
+ struct scatterlist sg_in[1];
+ struct scatterlist sg_out[2];
+ struct blkcipher_desc desc;
+ unsigned int encrypted_datalen;
+ char pad[16];
+ int ret;
+
+ encrypted_datalen = roundup(epayload->decrypted_datalen, blksize);
+ ret = init_blkcipher_desc(&desc, derived_key, derived_keylen,
+ epayload->iv, ivsize);
+ if (ret < 0)
+ goto out;
+ dump_encrypted_data(epayload, encrypted_datalen);
+
+ memset(pad, 0, sizeof pad);
+ sg_init_table(sg_in, 1);
+ sg_init_table(sg_out, 2);
+ sg_set_buf(sg_in, epayload->encrypted_data, encrypted_datalen);
+ sg_set_buf(&sg_out[0], epayload->decrypted_data,
+ epayload->decrypted_datalen);
+ sg_set_buf(&sg_out[1], pad, sizeof pad);
+
+ ret = crypto_blkcipher_decrypt(&desc, sg_out, sg_in, encrypted_datalen);
+ crypto_free_blkcipher(desc.tfm);
+ if (ret < 0)
+ goto out;
+ dump_decrypted_data(epayload);
+out:
+ return ret;
+}
+
+/* Allocate memory for decrypted key and datablob. */
+static struct encrypted_key_payload *encrypted_key_alloc(struct key *key,
+ const char *master_desc,
+ const char *datalen)
+{
+ struct encrypted_key_payload *epayload = NULL;
+ unsigned short datablob_len;
+ unsigned short decrypted_datalen;
+ unsigned int encrypted_datalen;
+ long dlen;
+ int ret;
+
+ ret = strict_strtol(datalen, 10, &dlen);
+ if (ret < 0 || dlen < MIN_DATA_SIZE || dlen > MAX_DATA_SIZE)
+ return ERR_PTR(-EINVAL);
+
+ decrypted_datalen = dlen;
+ encrypted_datalen = roundup(decrypted_datalen, blksize);
+
+ datablob_len = strlen(master_desc) + 1 + strlen(datalen) + 1
+ + ivsize + 1 + encrypted_datalen;
+
+ ret = key_payload_reserve(key, decrypted_datalen + datablob_len
+ + HASH_SIZE + 1);
+ if (ret < 0)
+ return ERR_PTR(ret);
+
+ epayload = kzalloc(sizeof(*epayload) + decrypted_datalen +
+ datablob_len + HASH_SIZE + 1, GFP_KERNEL);
+ if (!epayload)
+ return ERR_PTR(-ENOMEM);
+
+ epayload->decrypted_datalen = decrypted_datalen;
+ epayload->datablob_len = datablob_len;
+ return epayload;
+}
+
+static int encrypted_key_decrypt(struct encrypted_key_payload *epayload,
+ const char *hex_encoded_iv)
+{
+ struct key *mkey;
+ u8 derived_key[HASH_SIZE];
+ u8 *master_key;
+ u8 *hmac;
+ const char *hex_encoded_data;
+ unsigned int encrypted_datalen;
+ size_t master_keylen;
+ size_t asciilen;
+ int ret;
+
+ encrypted_datalen = roundup(epayload->decrypted_datalen, blksize);
+ asciilen = (ivsize + 1 + encrypted_datalen + HASH_SIZE) * 2;
+ if (strlen(hex_encoded_iv) != asciilen)
+ return -EINVAL;
+
+ hex_encoded_data = hex_encoded_iv + (2 * ivsize) + 2;
+ hex2bin(epayload->iv, hex_encoded_iv, ivsize);
+ hex2bin(epayload->encrypted_data, hex_encoded_data, encrypted_datalen);
+
+ hmac = epayload->master_desc + epayload->datablob_len;
+ hex2bin(hmac, hex_encoded_data + (encrypted_datalen * 2), HASH_SIZE);
+
+ mkey = request_master_key(epayload, &master_key, &master_keylen);
+ if (IS_ERR(mkey))
+ return PTR_ERR(mkey);
+
+ ret = datablob_hmac_verify(epayload, master_key, master_keylen);
+ if (ret < 0) {
+ pr_err("encrypted_key: bad hmac (%d)\n", ret);
+ goto out;
+ }
+
+ ret = get_derived_key(derived_key, ENC_KEY, master_key, master_keylen);
+ if (ret < 0)
+ goto out;
+
+ ret = derived_key_decrypt(epayload, derived_key, sizeof derived_key);
+ if (ret < 0)
+ pr_err("encrypted_key: failed to decrypt key (%d)\n", ret);
+out:
+ up_read(&mkey->sem);
+ key_put(mkey);
+ return ret;
+}
+
+static void __ekey_init(struct encrypted_key_payload *epayload,
+ const char *master_desc, const char *datalen)
+{
+ epayload->master_desc = epayload->decrypted_data
+ + epayload->decrypted_datalen;
+ epayload->datalen = epayload->master_desc + strlen(master_desc) + 1;
+ epayload->iv = epayload->datalen + strlen(datalen) + 1;
+ epayload->encrypted_data = epayload->iv + ivsize + 1;
+
+ memcpy(epayload->master_desc, master_desc, strlen(master_desc));
+ memcpy(epayload->datalen, datalen, strlen(datalen));
+}
+
+/*
+ * encrypted_init - initialize an encrypted key
+ *
+ * For a new key, use a random number for both the iv and data
+ * itself. For an old key, decrypt the hex encoded data.
+ */
+static int encrypted_init(struct encrypted_key_payload *epayload,
+ const char *master_desc, const char *datalen,
+ const char *hex_encoded_iv)
+{
+ int ret = 0;
+
+ __ekey_init(epayload, master_desc, datalen);
+ if (!hex_encoded_iv) {
+ get_random_bytes(epayload->iv, ivsize);
+
+ get_random_bytes(epayload->decrypted_data,
+ epayload->decrypted_datalen);
+ } else
+ ret = encrypted_key_decrypt(epayload, hex_encoded_iv);
+ return ret;
+}
+
+/*
+ * encrypted_instantiate - instantiate an encrypted key
+ *
+ * Decrypt an existing encrypted datablob or create a new encrypted key
+ * based on a kernel random number.
+ *
+ * On success, return 0. Otherwise return errno.
+ */
+static int encrypted_instantiate(struct key *key, const void *data,
+ size_t datalen)
+{
+ struct encrypted_key_payload *epayload = NULL;
+ char *datablob = NULL;
+ char *master_desc = NULL;
+ char *decrypted_datalen = NULL;
+ char *hex_encoded_iv = NULL;
+ int ret;
+
+ if (datalen <= 0 || datalen > 32767 || !data)
+ return -EINVAL;
+
+ datablob = kmalloc(datalen + 1, GFP_KERNEL);
+ if (!datablob)
+ return -ENOMEM;
+ datablob[datalen] = 0;
+ memcpy(datablob, data, datalen);
+ ret = datablob_parse(datablob, &master_desc, &decrypted_datalen,
+ &hex_encoded_iv);
+ if (ret < 0)
+ goto out;
+
+ epayload = encrypted_key_alloc(key, master_desc, decrypted_datalen);
+ if (IS_ERR(epayload)) {
+ ret = PTR_ERR(epayload);
+ goto out;
+ }
+ ret = encrypted_init(epayload, master_desc, decrypted_datalen,
+ hex_encoded_iv);
+ if (ret < 0) {
+ kfree(epayload);
+ goto out;
+ }
+
+ rcu_assign_pointer(key->payload.data, epayload);
+out:
+ kfree(datablob);
+ return ret;
+}
+
+static void encrypted_rcu_free(struct rcu_head *rcu)
+{
+ struct encrypted_key_payload *epayload;
+
+ epayload = container_of(rcu, struct encrypted_key_payload, rcu);
+ memset(epayload->decrypted_data, 0, epayload->decrypted_datalen);
+ kfree(epayload);
+}
+
+/*
+ * encrypted_update - update the master key description
+ *
+ * Change the master key description for an existing encrypted key.
+ * The next read will return an encrypted datablob using the new
+ * master key description.
+ *
+ * On success, return 0. Otherwise return errno.
+ */
+static int encrypted_update(struct key *key, const void *data, size_t datalen)
+{
+ struct encrypted_key_payload *epayload = key->payload.data;
+ struct encrypted_key_payload *new_epayload;
+ char *buf;
+ char *new_master_desc = NULL;
+ int ret = 0;
+
+ if (datalen <= 0 || datalen > 32767 || !data)
+ return -EINVAL;
+
+ buf = kmalloc(datalen + 1, GFP_KERNEL);
+ if (!buf)
+ return -ENOMEM;
+
+ buf[datalen] = 0;
+ memcpy(buf, data, datalen);
+ ret = datablob_parse(buf, &new_master_desc, NULL, NULL);
+ if (ret < 0)
+ goto out;
+
+ ret = valid_master_desc(new_master_desc, epayload->master_desc);
+ if (ret < 0)
+ goto out;
+
+ new_epayload = encrypted_key_alloc(key, new_master_desc,
+ epayload->datalen);
+ if (IS_ERR(new_epayload)) {
+ ret = PTR_ERR(new_epayload);
+ goto out;
+ }
+
+ __ekey_init(new_epayload, new_master_desc, epayload->datalen);
+
+ memcpy(new_epayload->iv, epayload->iv, ivsize);
+ memcpy(new_epayload->decrypted_data, epayload->decrypted_data,
+ epayload->decrypted_datalen);
+
+ rcu_assign_pointer(key->payload.data, new_epayload);
+ call_rcu(&epayload->rcu, encrypted_rcu_free);
+out:
+ kfree(buf);
+ return ret;
+}
+
+/*
+ * encrypted_read - format and copy the encrypted data to userspace
+ *
+ * The resulting datablob format is:
+ * <master-key name> <decrypted data length> <encrypted iv> <encrypted data>
+ *
+ * On success, return to userspace the encrypted key datablob size.
+ */
+static long encrypted_read(const struct key *key, char __user *buffer,
+ size_t buflen)
+{
+ struct encrypted_key_payload *epayload;
+ struct key *mkey;
+ u8 *master_key;
+ size_t master_keylen;
+ char derived_key[HASH_SIZE];
+ char *ascii_buf;
+ size_t asciiblob_len;
+ int ret;
+
+ epayload = rcu_dereference_key(key);
+
+ /* returns the hex encoded iv, encrypted-data, and hmac as ascii */
+ asciiblob_len = epayload->datablob_len + ivsize + 1
+ + roundup(epayload->decrypted_datalen, blksize)
+ + (HASH_SIZE * 2);
+
+ if (!buffer || buflen < asciiblob_len)
+ return asciiblob_len;
+
+ mkey = request_master_key(epayload, &master_key, &master_keylen);
+ if (IS_ERR(mkey))
+ return PTR_ERR(mkey);
+
+ ret = get_derived_key(derived_key, ENC_KEY, master_key, master_keylen);
+ if (ret < 0)
+ goto out;
+
+ ret = derived_key_encrypt(epayload, derived_key, sizeof derived_key);
+ if (ret < 0)
+ goto out;
+
+ ret = datablob_hmac_append(epayload, master_key, master_keylen);
+ if (ret < 0)
+ goto out;
+
+ ascii_buf = datablob_format(epayload, asciiblob_len);
+ if (!ascii_buf) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ up_read(&mkey->sem);
+ key_put(mkey);
+
+ if (copy_to_user(buffer, ascii_buf, asciiblob_len) != 0)
+ ret = -EFAULT;
+ kfree(ascii_buf);
+
+ return asciiblob_len;
+out:
+ up_read(&mkey->sem);
+ key_put(mkey);
+ return ret;
+}
+
+/*
+ * encrypted_destroy - before freeing the key, clear the decrypted data
+ *
+ * Before freeing the key, clear the memory containing the decrypted
+ * key data.
+ */
+static void encrypted_destroy(struct key *key)
+{
+ struct encrypted_key_payload *epayload = key->payload.data;
+
+ if (!epayload)
+ return;
+
+ memset(epayload->decrypted_data, 0, epayload->decrypted_datalen);
+ kfree(key->payload.data);
+}
+
+struct key_type key_type_encrypted = {
+ .name = "encrypted",
+ .instantiate = encrypted_instantiate,
+ .update = encrypted_update,
+ .match = user_match,
+ .destroy = encrypted_destroy,
+ .describe = user_describe,
+ .read = encrypted_read,
+};
+EXPORT_SYMBOL_GPL(key_type_encrypted);
+
+static void encrypted_shash_release(void)
+{
+ if (hashalg)
+ crypto_free_shash(hashalg);
+ if (hmacalg)
+ crypto_free_shash(hmacalg);
+}
+
+static int __init encrypted_shash_alloc(void)
+{
+ int ret;
+
+ hmacalg = crypto_alloc_shash(hmac_alg, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(hmacalg)) {
+ pr_info("encrypted_key: could not allocate crypto %s\n",
+ hmac_alg);
+ return PTR_ERR(hmacalg);
+ }
+
+ hashalg = crypto_alloc_shash(hash_alg, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(hashalg)) {
+ pr_info("encrypted_key: could not allocate crypto %s\n",
+ hash_alg);
+ ret = PTR_ERR(hashalg);
+ goto hashalg_fail;
+ }
+
+ return 0;
+
+hashalg_fail:
+ crypto_free_shash(hmacalg);
+ return ret;
+}
+
+static int __init init_encrypted(void)
+{
+ int ret;
+
+ ret = encrypted_shash_alloc();
+ if (ret < 0)
+ return ret;
+ ret = register_key_type(&key_type_encrypted);
+ if (ret < 0)
+ goto out;
+ return aes_get_sizes();
+out:
+ encrypted_shash_release();
+ return ret;
+
+}
+
+static void __exit cleanup_encrypted(void)
+{
+ encrypted_shash_release();
+ unregister_key_type(&key_type_encrypted);
+}
+
+late_initcall(init_encrypted);
+module_exit(cleanup_encrypted);
+
+MODULE_LICENSE("GPL");
diff --git a/security/keys/encrypted.h b/security/keys/encrypted.h
new file mode 100644
index 00000000..cef5e2f2
--- /dev/null
+++ b/security/keys/encrypted.h
@@ -0,0 +1,54 @@
+#ifndef __ENCRYPTED_KEY_H
+#define __ENCRYPTED_KEY_H
+
+#define ENCRYPTED_DEBUG 0
+
+#if ENCRYPTED_DEBUG
+static inline void dump_master_key(const u8 *master_key, size_t master_keylen)
+{
+ print_hex_dump(KERN_ERR, "master key: ", DUMP_PREFIX_NONE, 32, 1,
+ master_key, master_keylen, 0);
+}
+
+static inline void dump_decrypted_data(struct encrypted_key_payload *epayload)
+{
+ print_hex_dump(KERN_ERR, "decrypted data: ", DUMP_PREFIX_NONE, 32, 1,
+ epayload->decrypted_data,
+ epayload->decrypted_datalen, 0);
+}
+
+static inline void dump_encrypted_data(struct encrypted_key_payload *epayload,
+ unsigned int encrypted_datalen)
+{
+ print_hex_dump(KERN_ERR, "encrypted data: ", DUMP_PREFIX_NONE, 32, 1,
+ epayload->encrypted_data, encrypted_datalen, 0);
+}
+
+static inline void dump_hmac(const char *str, const u8 *digest,
+ unsigned int hmac_size)
+{
+ if (str)
+ pr_info("encrypted_key: %s", str);
+ print_hex_dump(KERN_ERR, "hmac: ", DUMP_PREFIX_NONE, 32, 1, digest,
+ hmac_size, 0);
+}
+#else
+static inline void dump_master_key(const u8 *master_key, size_t master_keylen)
+{
+}
+
+static inline void dump_decrypted_data(struct encrypted_key_payload *epayload)
+{
+}
+
+static inline void dump_encrypted_data(struct encrypted_key_payload *epayload,
+ unsigned int encrypted_datalen)
+{
+}
+
+static inline void dump_hmac(const char *str, const u8 *digest,
+ unsigned int hmac_size)
+{
+}
+#endif
+#endif
diff --git a/security/keys/gc.c b/security/keys/gc.c
new file mode 100644
index 00000000..89df6b5f
--- /dev/null
+++ b/security/keys/gc.c
@@ -0,0 +1,222 @@
+/* Key garbage collector
+ *
+ * Copyright (C) 2009 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <keys/keyring-type.h>
+#include "internal.h"
+
+/*
+ * Delay between key revocation/expiry in seconds
+ */
+unsigned key_gc_delay = 5 * 60;
+
+/*
+ * Reaper
+ */
+static void key_gc_timer_func(unsigned long);
+static void key_garbage_collector(struct work_struct *);
+static DEFINE_TIMER(key_gc_timer, key_gc_timer_func, 0, 0);
+static DECLARE_WORK(key_gc_work, key_garbage_collector);
+static key_serial_t key_gc_cursor; /* the last key the gc considered */
+static bool key_gc_again;
+static unsigned long key_gc_executing;
+static time_t key_gc_next_run = LONG_MAX;
+static time_t key_gc_new_timer;
+
+/*
+ * Schedule a garbage collection run.
+ * - time precision isn't particularly important
+ */
+void key_schedule_gc(time_t gc_at)
+{
+ unsigned long expires;
+ time_t now = current_kernel_time().tv_sec;
+
+ kenter("%ld", gc_at - now);
+
+ if (gc_at <= now) {
+ schedule_work(&key_gc_work);
+ } else if (gc_at < key_gc_next_run) {
+ expires = jiffies + (gc_at - now) * HZ;
+ mod_timer(&key_gc_timer, expires);
+ }
+}
+
+/*
+ * The garbage collector timer kicked off
+ */
+static void key_gc_timer_func(unsigned long data)
+{
+ kenter("");
+ key_gc_next_run = LONG_MAX;
+ schedule_work(&key_gc_work);
+}
+
+/*
+ * Garbage collect pointers from a keyring.
+ *
+ * Return true if we altered the keyring.
+ */
+static bool key_gc_keyring(struct key *keyring, time_t limit)
+ __releases(key_serial_lock)
+{
+ struct keyring_list *klist;
+ struct key *key;
+ int loop;
+
+ kenter("%x", key_serial(keyring));
+
+ if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
+ goto dont_gc;
+
+ /* scan the keyring looking for dead keys */
+ rcu_read_lock();
+ klist = rcu_dereference(keyring->payload.subscriptions);
+ if (!klist)
+ goto unlock_dont_gc;
+
+ for (loop = klist->nkeys - 1; loop >= 0; loop--) {
+ key = klist->keys[loop];
+ if (test_bit(KEY_FLAG_DEAD, &key->flags) ||
+ (key->expiry > 0 && key->expiry <= limit))
+ goto do_gc;
+ }
+
+unlock_dont_gc:
+ rcu_read_unlock();
+dont_gc:
+ kleave(" = false");
+ return false;
+
+do_gc:
+ rcu_read_unlock();
+ key_gc_cursor = keyring->serial;
+ key_get(keyring);
+ spin_unlock(&key_serial_lock);
+ keyring_gc(keyring, limit);
+ key_put(keyring);
+ kleave(" = true");
+ return true;
+}
+
+/*
+ * Garbage collector for keys. This involves scanning the keyrings for dead,
+ * expired and revoked keys that have overstayed their welcome
+ */
+static void key_garbage_collector(struct work_struct *work)
+{
+ struct rb_node *rb;
+ key_serial_t cursor;
+ struct key *key, *xkey;
+ time_t new_timer = LONG_MAX, limit, now;
+
+ now = current_kernel_time().tv_sec;
+ kenter("[%x,%ld]", key_gc_cursor, key_gc_new_timer - now);
+
+ if (test_and_set_bit(0, &key_gc_executing)) {
+ key_schedule_gc(current_kernel_time().tv_sec + 1);
+ kleave(" [busy; deferring]");
+ return;
+ }
+
+ limit = now;
+ if (limit > key_gc_delay)
+ limit -= key_gc_delay;
+ else
+ limit = key_gc_delay;
+
+ spin_lock(&key_serial_lock);
+
+ if (unlikely(RB_EMPTY_ROOT(&key_serial_tree))) {
+ spin_unlock(&key_serial_lock);
+ clear_bit(0, &key_gc_executing);
+ return;
+ }
+
+ cursor = key_gc_cursor;
+ if (cursor < 0)
+ cursor = 0;
+ if (cursor > 0)
+ new_timer = key_gc_new_timer;
+ else
+ key_gc_again = false;
+
+ /* find the first key above the cursor */
+ key = NULL;
+ rb = key_serial_tree.rb_node;
+ while (rb) {
+ xkey = rb_entry(rb, struct key, serial_node);
+ if (cursor < xkey->serial) {
+ key = xkey;
+ rb = rb->rb_left;
+ } else if (cursor > xkey->serial) {
+ rb = rb->rb_right;
+ } else {
+ rb = rb_next(rb);
+ if (!rb)
+ goto reached_the_end;
+ key = rb_entry(rb, struct key, serial_node);
+ break;
+ }
+ }
+
+ if (!key)
+ goto reached_the_end;
+
+ /* trawl through the keys looking for keyrings */
+ for (;;) {
+ if (key->expiry > limit && key->expiry < new_timer) {
+ kdebug("will expire %x in %ld",
+ key_serial(key), key->expiry - limit);
+ new_timer = key->expiry;
+ }
+
+ if (key->type == &key_type_keyring &&
+ key_gc_keyring(key, limit))
+ /* the gc had to release our lock so that the keyring
+ * could be modified, so we have to get it again */
+ goto gc_released_our_lock;
+
+ rb = rb_next(&key->serial_node);
+ if (!rb)
+ goto reached_the_end;
+ key = rb_entry(rb, struct key, serial_node);
+ }
+
+gc_released_our_lock:
+ kdebug("gc_released_our_lock");
+ key_gc_new_timer = new_timer;
+ key_gc_again = true;
+ clear_bit(0, &key_gc_executing);
+ schedule_work(&key_gc_work);
+ kleave(" [continue]");
+ return;
+
+ /* when we reach the end of the run, we set the timer for the next one */
+reached_the_end:
+ kdebug("reached_the_end");
+ spin_unlock(&key_serial_lock);
+ key_gc_new_timer = new_timer;
+ key_gc_cursor = 0;
+ clear_bit(0, &key_gc_executing);
+
+ if (key_gc_again) {
+ /* there may have been a key that expired whilst we were
+ * scanning, so if we discarded any links we should do another
+ * scan */
+ new_timer = now + 1;
+ key_schedule_gc(new_timer);
+ } else if (new_timer < LONG_MAX) {
+ new_timer += key_gc_delay;
+ key_schedule_gc(new_timer);
+ }
+ kleave(" [end]");
+}
diff --git a/security/keys/internal.h b/security/keys/internal.h
new file mode 100644
index 00000000..f375152a
--- /dev/null
+++ b/security/keys/internal.h
@@ -0,0 +1,246 @@
+/* Authentication token and access key management internal defs
+ *
+ * Copyright (C) 2003-5, 2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#ifndef _INTERNAL_H
+#define _INTERNAL_H
+
+#include <linux/sched.h>
+#include <linux/key-type.h>
+
+#ifdef __KDEBUG
+#define kenter(FMT, ...) \
+ printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
+#define kleave(FMT, ...) \
+ printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
+#define kdebug(FMT, ...) \
+ printk(KERN_DEBUG " "FMT"\n", ##__VA_ARGS__)
+#else
+#define kenter(FMT, ...) \
+ no_printk(KERN_DEBUG "==> %s("FMT")\n", __func__, ##__VA_ARGS__)
+#define kleave(FMT, ...) \
+ no_printk(KERN_DEBUG "<== %s()"FMT"\n", __func__, ##__VA_ARGS__)
+#define kdebug(FMT, ...) \
+ no_printk(KERN_DEBUG FMT"\n", ##__VA_ARGS__)
+#endif
+
+extern struct key_type key_type_user;
+
+/*****************************************************************************/
+/*
+ * Keep track of keys for a user.
+ *
+ * This needs to be separate to user_struct to avoid a refcount-loop
+ * (user_struct pins some keyrings which pin this struct).
+ *
+ * We also keep track of keys under request from userspace for this UID here.
+ */
+struct key_user {
+ struct rb_node node;
+ struct mutex cons_lock; /* construction initiation lock */
+ spinlock_t lock;
+ atomic_t usage; /* for accessing qnkeys & qnbytes */
+ atomic_t nkeys; /* number of keys */
+ atomic_t nikeys; /* number of instantiated keys */
+ uid_t uid;
+ struct user_namespace *user_ns;
+ int qnkeys; /* number of keys allocated to this user */
+ int qnbytes; /* number of bytes allocated to this user */
+};
+
+extern struct rb_root key_user_tree;
+extern spinlock_t key_user_lock;
+extern struct key_user root_key_user;
+
+extern struct key_user *key_user_lookup(uid_t uid,
+ struct user_namespace *user_ns);
+extern void key_user_put(struct key_user *user);
+
+/*
+ * Key quota limits.
+ * - root has its own separate limits to everyone else
+ */
+extern unsigned key_quota_root_maxkeys;
+extern unsigned key_quota_root_maxbytes;
+extern unsigned key_quota_maxkeys;
+extern unsigned key_quota_maxbytes;
+
+#define KEYQUOTA_LINK_BYTES 4 /* a link in a keyring is worth 4 bytes */
+
+
+extern struct rb_root key_serial_tree;
+extern spinlock_t key_serial_lock;
+extern struct mutex key_construction_mutex;
+extern wait_queue_head_t request_key_conswq;
+
+
+extern struct key_type *key_type_lookup(const char *type);
+extern void key_type_put(struct key_type *ktype);
+
+extern int __key_link_begin(struct key *keyring,
+ const struct key_type *type,
+ const char *description,
+ unsigned long *_prealloc);
+extern int __key_link_check_live_key(struct key *keyring, struct key *key);
+extern void __key_link(struct key *keyring, struct key *key,
+ unsigned long *_prealloc);
+extern void __key_link_end(struct key *keyring,
+ struct key_type *type,
+ unsigned long prealloc);
+
+extern key_ref_t __keyring_search_one(key_ref_t keyring_ref,
+ const struct key_type *type,
+ const char *description,
+ key_perm_t perm);
+
+extern struct key *keyring_search_instkey(struct key *keyring,
+ key_serial_t target_id);
+
+typedef int (*key_match_func_t)(const struct key *, const void *);
+
+extern key_ref_t keyring_search_aux(key_ref_t keyring_ref,
+ const struct cred *cred,
+ struct key_type *type,
+ const void *description,
+ key_match_func_t match,
+ bool no_state_check);
+
+extern key_ref_t search_my_process_keyrings(struct key_type *type,
+ const void *description,
+ key_match_func_t match,
+ bool no_state_check,
+ const struct cred *cred);
+extern key_ref_t search_process_keyrings(struct key_type *type,
+ const void *description,
+ key_match_func_t match,
+ const struct cred *cred);
+
+extern struct key *find_keyring_by_name(const char *name, bool skip_perm_check);
+
+extern int install_user_keyrings(void);
+extern int install_thread_keyring_to_cred(struct cred *);
+extern int install_process_keyring_to_cred(struct cred *);
+extern int install_session_keyring_to_cred(struct cred *, struct key *);
+
+extern struct key *request_key_and_link(struct key_type *type,
+ const char *description,
+ const void *callout_info,
+ size_t callout_len,
+ void *aux,
+ struct key *dest_keyring,
+ unsigned long flags);
+
+extern int lookup_user_key_possessed(const struct key *key, const void *target);
+extern key_ref_t lookup_user_key(key_serial_t id, unsigned long flags,
+ key_perm_t perm);
+#define KEY_LOOKUP_CREATE 0x01
+#define KEY_LOOKUP_PARTIAL 0x02
+#define KEY_LOOKUP_FOR_UNLINK 0x04
+
+extern long join_session_keyring(const char *name);
+
+extern unsigned key_gc_delay;
+extern void keyring_gc(struct key *keyring, time_t limit);
+extern void key_schedule_gc(time_t expiry_at);
+
+extern int key_task_permission(const key_ref_t key_ref,
+ const struct cred *cred,
+ key_perm_t perm);
+
+/*
+ * Check to see whether permission is granted to use a key in the desired way.
+ */
+static inline int key_permission(const key_ref_t key_ref, key_perm_t perm)
+{
+ return key_task_permission(key_ref, current_cred(), perm);
+}
+
+/* required permissions */
+#define KEY_VIEW 0x01 /* require permission to view attributes */
+#define KEY_READ 0x02 /* require permission to read content */
+#define KEY_WRITE 0x04 /* require permission to update / modify */
+#define KEY_SEARCH 0x08 /* require permission to search (keyring) or find (key) */
+#define KEY_LINK 0x10 /* require permission to link */
+#define KEY_SETATTR 0x20 /* require permission to change attributes */
+#define KEY_ALL 0x3f /* all the above permissions */
+
+/*
+ * Authorisation record for request_key().
+ */
+struct request_key_auth {
+ struct key *target_key;
+ struct key *dest_keyring;
+ const struct cred *cred;
+ void *callout_info;
+ size_t callout_len;
+ pid_t pid;
+};
+
+extern struct key_type key_type_request_key_auth;
+extern struct key *request_key_auth_new(struct key *target,
+ const void *callout_info,
+ size_t callout_len,
+ struct key *dest_keyring);
+
+extern struct key *key_get_instantiation_authkey(key_serial_t target_id);
+
+/*
+ * keyctl() functions
+ */
+extern long keyctl_get_keyring_ID(key_serial_t, int);
+extern long keyctl_join_session_keyring(const char __user *);
+extern long keyctl_update_key(key_serial_t, const void __user *, size_t);
+extern long keyctl_revoke_key(key_serial_t);
+extern long keyctl_keyring_clear(key_serial_t);
+extern long keyctl_keyring_link(key_serial_t, key_serial_t);
+extern long keyctl_keyring_unlink(key_serial_t, key_serial_t);
+extern long keyctl_describe_key(key_serial_t, char __user *, size_t);
+extern long keyctl_keyring_search(key_serial_t, const char __user *,
+ const char __user *, key_serial_t);
+extern long keyctl_read_key(key_serial_t, char __user *, size_t);
+extern long keyctl_chown_key(key_serial_t, uid_t, gid_t);
+extern long keyctl_setperm_key(key_serial_t, key_perm_t);
+extern long keyctl_instantiate_key(key_serial_t, const void __user *,
+ size_t, key_serial_t);
+extern long keyctl_negate_key(key_serial_t, unsigned, key_serial_t);
+extern long keyctl_set_reqkey_keyring(int);
+extern long keyctl_set_timeout(key_serial_t, unsigned);
+extern long keyctl_assume_authority(key_serial_t);
+extern long keyctl_get_security(key_serial_t keyid, char __user *buffer,
+ size_t buflen);
+extern long keyctl_session_to_parent(void);
+extern long keyctl_reject_key(key_serial_t, unsigned, unsigned, key_serial_t);
+extern long keyctl_instantiate_key_iov(key_serial_t,
+ const struct iovec __user *,
+ unsigned, key_serial_t);
+
+extern long keyctl_instantiate_key_common(key_serial_t,
+ const struct iovec __user *,
+ unsigned, size_t, key_serial_t);
+
+/*
+ * Debugging key validation
+ */
+#ifdef KEY_DEBUGGING
+extern void __key_check(const struct key *);
+
+static inline void key_check(const struct key *key)
+{
+ if (key && (IS_ERR(key) || key->magic != KEY_DEBUG_MAGIC))
+ __key_check(key);
+}
+
+#else
+
+#define key_check(key) do {} while(0)
+
+#endif
+
+#endif /* _INTERNAL_H */
diff --git a/security/keys/key.c b/security/keys/key.c
new file mode 100644
index 00000000..f7f9d93f
--- /dev/null
+++ b/security/keys/key.c
@@ -0,0 +1,1118 @@
+/* Basic authentication token and access key management
+ *
+ * Copyright (C) 2004-2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/poison.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/security.h>
+#include <linux/workqueue.h>
+#include <linux/random.h>
+#include <linux/err.h>
+#include <linux/user_namespace.h>
+#include "internal.h"
+
+static struct kmem_cache *key_jar;
+struct rb_root key_serial_tree; /* tree of keys indexed by serial */
+DEFINE_SPINLOCK(key_serial_lock);
+
+struct rb_root key_user_tree; /* tree of quota records indexed by UID */
+DEFINE_SPINLOCK(key_user_lock);
+
+unsigned int key_quota_root_maxkeys = 200; /* root's key count quota */
+unsigned int key_quota_root_maxbytes = 20000; /* root's key space quota */
+unsigned int key_quota_maxkeys = 200; /* general key count quota */
+unsigned int key_quota_maxbytes = 20000; /* general key space quota */
+
+static LIST_HEAD(key_types_list);
+static DECLARE_RWSEM(key_types_sem);
+
+static void key_cleanup(struct work_struct *work);
+static DECLARE_WORK(key_cleanup_task, key_cleanup);
+
+/* We serialise key instantiation and link */
+DEFINE_MUTEX(key_construction_mutex);
+
+/* Any key who's type gets unegistered will be re-typed to this */
+static struct key_type key_type_dead = {
+ .name = "dead",
+};
+
+#ifdef KEY_DEBUGGING
+void __key_check(const struct key *key)
+{
+ printk("__key_check: key %p {%08x} should be {%08x}\n",
+ key, key->magic, KEY_DEBUG_MAGIC);
+ BUG();
+}
+#endif
+
+/*
+ * Get the key quota record for a user, allocating a new record if one doesn't
+ * already exist.
+ */
+struct key_user *key_user_lookup(uid_t uid, struct user_namespace *user_ns)
+{
+ struct key_user *candidate = NULL, *user;
+ struct rb_node *parent = NULL;
+ struct rb_node **p;
+
+try_again:
+ p = &key_user_tree.rb_node;
+ spin_lock(&key_user_lock);
+
+ /* search the tree for a user record with a matching UID */
+ while (*p) {
+ parent = *p;
+ user = rb_entry(parent, struct key_user, node);
+
+ if (uid < user->uid)
+ p = &(*p)->rb_left;
+ else if (uid > user->uid)
+ p = &(*p)->rb_right;
+ else if (user_ns < user->user_ns)
+ p = &(*p)->rb_left;
+ else if (user_ns > user->user_ns)
+ p = &(*p)->rb_right;
+ else
+ goto found;
+ }
+
+ /* if we get here, we failed to find a match in the tree */
+ if (!candidate) {
+ /* allocate a candidate user record if we don't already have
+ * one */
+ spin_unlock(&key_user_lock);
+
+ user = NULL;
+ candidate = kmalloc(sizeof(struct key_user), GFP_KERNEL);
+ if (unlikely(!candidate))
+ goto out;
+
+ /* the allocation may have scheduled, so we need to repeat the
+ * search lest someone else added the record whilst we were
+ * asleep */
+ goto try_again;
+ }
+
+ /* if we get here, then the user record still hadn't appeared on the
+ * second pass - so we use the candidate record */
+ atomic_set(&candidate->usage, 1);
+ atomic_set(&candidate->nkeys, 0);
+ atomic_set(&candidate->nikeys, 0);
+ candidate->uid = uid;
+ candidate->user_ns = get_user_ns(user_ns);
+ candidate->qnkeys = 0;
+ candidate->qnbytes = 0;
+ spin_lock_init(&candidate->lock);
+ mutex_init(&candidate->cons_lock);
+
+ rb_link_node(&candidate->node, parent, p);
+ rb_insert_color(&candidate->node, &key_user_tree);
+ spin_unlock(&key_user_lock);
+ user = candidate;
+ goto out;
+
+ /* okay - we found a user record for this UID */
+found:
+ atomic_inc(&user->usage);
+ spin_unlock(&key_user_lock);
+ kfree(candidate);
+out:
+ return user;
+}
+
+/*
+ * Dispose of a user structure
+ */
+void key_user_put(struct key_user *user)
+{
+ if (atomic_dec_and_lock(&user->usage, &key_user_lock)) {
+ rb_erase(&user->node, &key_user_tree);
+ spin_unlock(&key_user_lock);
+ put_user_ns(user->user_ns);
+
+ kfree(user);
+ }
+}
+
+/*
+ * Allocate a serial number for a key. These are assigned randomly to avoid
+ * security issues through covert channel problems.
+ */
+static inline void key_alloc_serial(struct key *key)
+{
+ struct rb_node *parent, **p;
+ struct key *xkey;
+
+ /* propose a random serial number and look for a hole for it in the
+ * serial number tree */
+ do {
+ get_random_bytes(&key->serial, sizeof(key->serial));
+
+ key->serial >>= 1; /* negative numbers are not permitted */
+ } while (key->serial < 3);
+
+ spin_lock(&key_serial_lock);
+
+attempt_insertion:
+ parent = NULL;
+ p = &key_serial_tree.rb_node;
+
+ while (*p) {
+ parent = *p;
+ xkey = rb_entry(parent, struct key, serial_node);
+
+ if (key->serial < xkey->serial)
+ p = &(*p)->rb_left;
+ else if (key->serial > xkey->serial)
+ p = &(*p)->rb_right;
+ else
+ goto serial_exists;
+ }
+
+ /* we've found a suitable hole - arrange for this key to occupy it */
+ rb_link_node(&key->serial_node, parent, p);
+ rb_insert_color(&key->serial_node, &key_serial_tree);
+
+ spin_unlock(&key_serial_lock);
+ return;
+
+ /* we found a key with the proposed serial number - walk the tree from
+ * that point looking for the next unused serial number */
+serial_exists:
+ for (;;) {
+ key->serial++;
+ if (key->serial < 3) {
+ key->serial = 3;
+ goto attempt_insertion;
+ }
+
+ parent = rb_next(parent);
+ if (!parent)
+ goto attempt_insertion;
+
+ xkey = rb_entry(parent, struct key, serial_node);
+ if (key->serial < xkey->serial)
+ goto attempt_insertion;
+ }
+}
+
+/**
+ * key_alloc - Allocate a key of the specified type.
+ * @type: The type of key to allocate.
+ * @desc: The key description to allow the key to be searched out.
+ * @uid: The owner of the new key.
+ * @gid: The group ID for the new key's group permissions.
+ * @cred: The credentials specifying UID namespace.
+ * @perm: The permissions mask of the new key.
+ * @flags: Flags specifying quota properties.
+ *
+ * Allocate a key of the specified type with the attributes given. The key is
+ * returned in an uninstantiated state and the caller needs to instantiate the
+ * key before returning.
+ *
+ * The user's key count quota is updated to reflect the creation of the key and
+ * the user's key data quota has the default for the key type reserved. The
+ * instantiation function should amend this as necessary. If insufficient
+ * quota is available, -EDQUOT will be returned.
+ *
+ * The LSM security modules can prevent a key being created, in which case
+ * -EACCES will be returned.
+ *
+ * Returns a pointer to the new key if successful and an error code otherwise.
+ *
+ * Note that the caller needs to ensure the key type isn't uninstantiated.
+ * Internally this can be done by locking key_types_sem. Externally, this can
+ * be done by either never unregistering the key type, or making sure
+ * key_alloc() calls don't race with module unloading.
+ */
+struct key *key_alloc(struct key_type *type, const char *desc,
+ uid_t uid, gid_t gid, const struct cred *cred,
+ key_perm_t perm, unsigned long flags)
+{
+ struct key_user *user = NULL;
+ struct key *key;
+ size_t desclen, quotalen;
+ int ret;
+
+ key = ERR_PTR(-EINVAL);
+ if (!desc || !*desc)
+ goto error;
+
+ if (type->vet_description) {
+ ret = type->vet_description(desc);
+ if (ret < 0) {
+ key = ERR_PTR(ret);
+ goto error;
+ }
+ }
+
+ desclen = strlen(desc) + 1;
+ quotalen = desclen + type->def_datalen;
+
+ /* get hold of the key tracking for this user */
+ user = key_user_lookup(uid, cred->user->user_ns);
+ if (!user)
+ goto no_memory_1;
+
+ /* check that the user's quota permits allocation of another key and
+ * its description */
+ if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) {
+ unsigned maxkeys = (uid == 0) ?
+ key_quota_root_maxkeys : key_quota_maxkeys;
+ unsigned maxbytes = (uid == 0) ?
+ key_quota_root_maxbytes : key_quota_maxbytes;
+
+ spin_lock(&user->lock);
+ if (!(flags & KEY_ALLOC_QUOTA_OVERRUN)) {
+ if (user->qnkeys + 1 >= maxkeys ||
+ user->qnbytes + quotalen >= maxbytes ||
+ user->qnbytes + quotalen < user->qnbytes)
+ goto no_quota;
+ }
+
+ user->qnkeys++;
+ user->qnbytes += quotalen;
+ spin_unlock(&user->lock);
+ }
+
+ /* allocate and initialise the key and its description */
+ key = kmem_cache_alloc(key_jar, GFP_KERNEL);
+ if (!key)
+ goto no_memory_2;
+
+ if (desc) {
+ key->description = kmemdup(desc, desclen, GFP_KERNEL);
+ if (!key->description)
+ goto no_memory_3;
+ }
+
+ atomic_set(&key->usage, 1);
+ init_rwsem(&key->sem);
+ key->type = type;
+ key->user = user;
+ key->quotalen = quotalen;
+ key->datalen = type->def_datalen;
+ key->uid = uid;
+ key->gid = gid;
+ key->perm = perm;
+ key->flags = 0;
+ key->expiry = 0;
+ key->payload.data = NULL;
+ key->security = NULL;
+
+ if (!(flags & KEY_ALLOC_NOT_IN_QUOTA))
+ key->flags |= 1 << KEY_FLAG_IN_QUOTA;
+
+ memset(&key->type_data, 0, sizeof(key->type_data));
+
+#ifdef KEY_DEBUGGING
+ key->magic = KEY_DEBUG_MAGIC;
+#endif
+
+ /* let the security module know about the key */
+ ret = security_key_alloc(key, cred, flags);
+ if (ret < 0)
+ goto security_error;
+
+ /* publish the key by giving it a serial number */
+ atomic_inc(&user->nkeys);
+ key_alloc_serial(key);
+
+error:
+ return key;
+
+security_error:
+ kfree(key->description);
+ kmem_cache_free(key_jar, key);
+ if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) {
+ spin_lock(&user->lock);
+ user->qnkeys--;
+ user->qnbytes -= quotalen;
+ spin_unlock(&user->lock);
+ }
+ key_user_put(user);
+ key = ERR_PTR(ret);
+ goto error;
+
+no_memory_3:
+ kmem_cache_free(key_jar, key);
+no_memory_2:
+ if (!(flags & KEY_ALLOC_NOT_IN_QUOTA)) {
+ spin_lock(&user->lock);
+ user->qnkeys--;
+ user->qnbytes -= quotalen;
+ spin_unlock(&user->lock);
+ }
+ key_user_put(user);
+no_memory_1:
+ key = ERR_PTR(-ENOMEM);
+ goto error;
+
+no_quota:
+ spin_unlock(&user->lock);
+ key_user_put(user);
+ key = ERR_PTR(-EDQUOT);
+ goto error;
+}
+EXPORT_SYMBOL(key_alloc);
+
+/**
+ * key_payload_reserve - Adjust data quota reservation for the key's payload
+ * @key: The key to make the reservation for.
+ * @datalen: The amount of data payload the caller now wants.
+ *
+ * Adjust the amount of the owning user's key data quota that a key reserves.
+ * If the amount is increased, then -EDQUOT may be returned if there isn't
+ * enough free quota available.
+ *
+ * If successful, 0 is returned.
+ */
+int key_payload_reserve(struct key *key, size_t datalen)
+{
+ int delta = (int)datalen - key->datalen;
+ int ret = 0;
+
+ key_check(key);
+
+ /* contemplate the quota adjustment */
+ if (delta != 0 && test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+ unsigned maxbytes = (key->user->uid == 0) ?
+ key_quota_root_maxbytes : key_quota_maxbytes;
+
+ spin_lock(&key->user->lock);
+
+ if (delta > 0 &&
+ (key->user->qnbytes + delta >= maxbytes ||
+ key->user->qnbytes + delta < key->user->qnbytes)) {
+ ret = -EDQUOT;
+ }
+ else {
+ key->user->qnbytes += delta;
+ key->quotalen += delta;
+ }
+ spin_unlock(&key->user->lock);
+ }
+
+ /* change the recorded data length if that didn't generate an error */
+ if (ret == 0)
+ key->datalen = datalen;
+
+ return ret;
+}
+EXPORT_SYMBOL(key_payload_reserve);
+
+/*
+ * Instantiate a key and link it into the target keyring atomically. Must be
+ * called with the target keyring's semaphore writelocked. The target key's
+ * semaphore need not be locked as instantiation is serialised by
+ * key_construction_mutex.
+ */
+static int __key_instantiate_and_link(struct key *key,
+ const void *data,
+ size_t datalen,
+ struct key *keyring,
+ struct key *authkey,
+ unsigned long *_prealloc)
+{
+ int ret, awaken;
+
+ key_check(key);
+ key_check(keyring);
+
+ awaken = 0;
+ ret = -EBUSY;
+
+ mutex_lock(&key_construction_mutex);
+
+ /* can't instantiate twice */
+ if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) {
+ /* instantiate the key */
+ ret = key->type->instantiate(key, data, datalen);
+
+ if (ret == 0) {
+ /* mark the key as being instantiated */
+ atomic_inc(&key->user->nikeys);
+ set_bit(KEY_FLAG_INSTANTIATED, &key->flags);
+
+ if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags))
+ awaken = 1;
+
+ /* and link it into the destination keyring */
+ if (keyring)
+ __key_link(keyring, key, _prealloc);
+
+ /* disable the authorisation key */
+ if (authkey)
+ key_revoke(authkey);
+ }
+ }
+
+ mutex_unlock(&key_construction_mutex);
+
+ /* wake up anyone waiting for a key to be constructed */
+ if (awaken)
+ wake_up_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT);
+
+ return ret;
+}
+
+/**
+ * key_instantiate_and_link - Instantiate a key and link it into the keyring.
+ * @key: The key to instantiate.
+ * @data: The data to use to instantiate the keyring.
+ * @datalen: The length of @data.
+ * @keyring: Keyring to create a link in on success (or NULL).
+ * @authkey: The authorisation token permitting instantiation.
+ *
+ * Instantiate a key that's in the uninstantiated state using the provided data
+ * and, if successful, link it in to the destination keyring if one is
+ * supplied.
+ *
+ * If successful, 0 is returned, the authorisation token is revoked and anyone
+ * waiting for the key is woken up. If the key was already instantiated,
+ * -EBUSY will be returned.
+ */
+int key_instantiate_and_link(struct key *key,
+ const void *data,
+ size_t datalen,
+ struct key *keyring,
+ struct key *authkey)
+{
+ unsigned long prealloc;
+ int ret;
+
+ if (keyring) {
+ ret = __key_link_begin(keyring, key->type, key->description,
+ &prealloc);
+ if (ret < 0)
+ return ret;
+ }
+
+ ret = __key_instantiate_and_link(key, data, datalen, keyring, authkey,
+ &prealloc);
+
+ if (keyring)
+ __key_link_end(keyring, key->type, prealloc);
+
+ return ret;
+}
+
+EXPORT_SYMBOL(key_instantiate_and_link);
+
+/**
+ * key_reject_and_link - Negatively instantiate a key and link it into the keyring.
+ * @key: The key to instantiate.
+ * @timeout: The timeout on the negative key.
+ * @error: The error to return when the key is hit.
+ * @keyring: Keyring to create a link in on success (or NULL).
+ * @authkey: The authorisation token permitting instantiation.
+ *
+ * Negatively instantiate a key that's in the uninstantiated state and, if
+ * successful, set its timeout and stored error and link it in to the
+ * destination keyring if one is supplied. The key and any links to the key
+ * will be automatically garbage collected after the timeout expires.
+ *
+ * Negative keys are used to rate limit repeated request_key() calls by causing
+ * them to return the stored error code (typically ENOKEY) until the negative
+ * key expires.
+ *
+ * If successful, 0 is returned, the authorisation token is revoked and anyone
+ * waiting for the key is woken up. If the key was already instantiated,
+ * -EBUSY will be returned.
+ */
+int key_reject_and_link(struct key *key,
+ unsigned timeout,
+ unsigned error,
+ struct key *keyring,
+ struct key *authkey)
+{
+ unsigned long prealloc;
+ struct timespec now;
+ int ret, awaken, link_ret = 0;
+
+ key_check(key);
+ key_check(keyring);
+
+ awaken = 0;
+ ret = -EBUSY;
+
+ if (keyring)
+ link_ret = __key_link_begin(keyring, key->type,
+ key->description, &prealloc);
+
+ mutex_lock(&key_construction_mutex);
+
+ /* can't instantiate twice */
+ if (!test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) {
+ /* mark the key as being negatively instantiated */
+ atomic_inc(&key->user->nikeys);
+ set_bit(KEY_FLAG_NEGATIVE, &key->flags);
+ set_bit(KEY_FLAG_INSTANTIATED, &key->flags);
+ key->type_data.reject_error = -error;
+ now = current_kernel_time();
+ key->expiry = now.tv_sec + timeout;
+ key_schedule_gc(key->expiry + key_gc_delay);
+
+ if (test_and_clear_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags))
+ awaken = 1;
+
+ ret = 0;
+
+ /* and link it into the destination keyring */
+ if (keyring && link_ret == 0)
+ __key_link(keyring, key, &prealloc);
+
+ /* disable the authorisation key */
+ if (authkey)
+ key_revoke(authkey);
+ }
+
+ mutex_unlock(&key_construction_mutex);
+
+ if (keyring)
+ __key_link_end(keyring, key->type, prealloc);
+
+ /* wake up anyone waiting for a key to be constructed */
+ if (awaken)
+ wake_up_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT);
+
+ return ret == 0 ? link_ret : ret;
+}
+EXPORT_SYMBOL(key_reject_and_link);
+
+/*
+ * Garbage collect keys in process context so that we don't have to disable
+ * interrupts all over the place.
+ *
+ * key_put() schedules this rather than trying to do the cleanup itself, which
+ * means key_put() doesn't have to sleep.
+ */
+static void key_cleanup(struct work_struct *work)
+{
+ struct rb_node *_n;
+ struct key *key;
+
+go_again:
+ /* look for a dead key in the tree */
+ spin_lock(&key_serial_lock);
+
+ for (_n = rb_first(&key_serial_tree); _n; _n = rb_next(_n)) {
+ key = rb_entry(_n, struct key, serial_node);
+
+ if (atomic_read(&key->usage) == 0)
+ goto found_dead_key;
+ }
+
+ spin_unlock(&key_serial_lock);
+ return;
+
+found_dead_key:
+ /* we found a dead key - once we've removed it from the tree, we can
+ * drop the lock */
+ rb_erase(&key->serial_node, &key_serial_tree);
+ spin_unlock(&key_serial_lock);
+
+ key_check(key);
+
+ security_key_free(key);
+
+ /* deal with the user's key tracking and quota */
+ if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+ spin_lock(&key->user->lock);
+ key->user->qnkeys--;
+ key->user->qnbytes -= key->quotalen;
+ spin_unlock(&key->user->lock);
+ }
+
+ atomic_dec(&key->user->nkeys);
+ if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
+ atomic_dec(&key->user->nikeys);
+
+ key_user_put(key->user);
+
+ /* now throw away the key memory */
+ if (key->type->destroy)
+ key->type->destroy(key);
+
+ kfree(key->description);
+
+#ifdef KEY_DEBUGGING
+ key->magic = KEY_DEBUG_MAGIC_X;
+#endif
+ kmem_cache_free(key_jar, key);
+
+ /* there may, of course, be more than one key to destroy */
+ goto go_again;
+}
+
+/**
+ * key_put - Discard a reference to a key.
+ * @key: The key to discard a reference from.
+ *
+ * Discard a reference to a key, and when all the references are gone, we
+ * schedule the cleanup task to come and pull it out of the tree in process
+ * context at some later time.
+ */
+void key_put(struct key *key)
+{
+ if (key) {
+ key_check(key);
+
+ if (atomic_dec_and_test(&key->usage))
+ schedule_work(&key_cleanup_task);
+ }
+}
+EXPORT_SYMBOL(key_put);
+
+/*
+ * Find a key by its serial number.
+ */
+struct key *key_lookup(key_serial_t id)
+{
+ struct rb_node *n;
+ struct key *key;
+
+ spin_lock(&key_serial_lock);
+
+ /* search the tree for the specified key */
+ n = key_serial_tree.rb_node;
+ while (n) {
+ key = rb_entry(n, struct key, serial_node);
+
+ if (id < key->serial)
+ n = n->rb_left;
+ else if (id > key->serial)
+ n = n->rb_right;
+ else
+ goto found;
+ }
+
+not_found:
+ key = ERR_PTR(-ENOKEY);
+ goto error;
+
+found:
+ /* pretend it doesn't exist if it is awaiting deletion */
+ if (atomic_read(&key->usage) == 0)
+ goto not_found;
+
+ /* this races with key_put(), but that doesn't matter since key_put()
+ * doesn't actually change the key
+ */
+ atomic_inc(&key->usage);
+
+error:
+ spin_unlock(&key_serial_lock);
+ return key;
+}
+
+/*
+ * Find and lock the specified key type against removal.
+ *
+ * We return with the sem read-locked if successful. If the type wasn't
+ * available -ENOKEY is returned instead.
+ */
+struct key_type *key_type_lookup(const char *type)
+{
+ struct key_type *ktype;
+
+ down_read(&key_types_sem);
+
+ /* look up the key type to see if it's one of the registered kernel
+ * types */
+ list_for_each_entry(ktype, &key_types_list, link) {
+ if (strcmp(ktype->name, type) == 0)
+ goto found_kernel_type;
+ }
+
+ up_read(&key_types_sem);
+ ktype = ERR_PTR(-ENOKEY);
+
+found_kernel_type:
+ return ktype;
+}
+
+/*
+ * Unlock a key type locked by key_type_lookup().
+ */
+void key_type_put(struct key_type *ktype)
+{
+ up_read(&key_types_sem);
+}
+
+/*
+ * Attempt to update an existing key.
+ *
+ * The key is given to us with an incremented refcount that we need to discard
+ * if we get an error.
+ */
+static inline key_ref_t __key_update(key_ref_t key_ref,
+ const void *payload, size_t plen)
+{
+ struct key *key = key_ref_to_ptr(key_ref);
+ int ret;
+
+ /* need write permission on the key to update it */
+ ret = key_permission(key_ref, KEY_WRITE);
+ if (ret < 0)
+ goto error;
+
+ ret = -EEXIST;
+ if (!key->type->update)
+ goto error;
+
+ down_write(&key->sem);
+
+ ret = key->type->update(key, payload, plen);
+ if (ret == 0)
+ /* updating a negative key instantiates it */
+ clear_bit(KEY_FLAG_NEGATIVE, &key->flags);
+
+ up_write(&key->sem);
+
+ if (ret < 0)
+ goto error;
+out:
+ return key_ref;
+
+error:
+ key_put(key);
+ key_ref = ERR_PTR(ret);
+ goto out;
+}
+
+/**
+ * key_create_or_update - Update or create and instantiate a key.
+ * @keyring_ref: A pointer to the destination keyring with possession flag.
+ * @type: The type of key.
+ * @description: The searchable description for the key.
+ * @payload: The data to use to instantiate or update the key.
+ * @plen: The length of @payload.
+ * @perm: The permissions mask for a new key.
+ * @flags: The quota flags for a new key.
+ *
+ * Search the destination keyring for a key of the same description and if one
+ * is found, update it, otherwise create and instantiate a new one and create a
+ * link to it from that keyring.
+ *
+ * If perm is KEY_PERM_UNDEF then an appropriate key permissions mask will be
+ * concocted.
+ *
+ * Returns a pointer to the new key if successful, -ENODEV if the key type
+ * wasn't available, -ENOTDIR if the keyring wasn't a keyring, -EACCES if the
+ * caller isn't permitted to modify the keyring or the LSM did not permit
+ * creation of the key.
+ *
+ * On success, the possession flag from the keyring ref will be tacked on to
+ * the key ref before it is returned.
+ */
+key_ref_t key_create_or_update(key_ref_t keyring_ref,
+ const char *type,
+ const char *description,
+ const void *payload,
+ size_t plen,
+ key_perm_t perm,
+ unsigned long flags)
+{
+ unsigned long prealloc;
+ const struct cred *cred = current_cred();
+ struct key_type *ktype;
+ struct key *keyring, *key = NULL;
+ key_ref_t key_ref;
+ int ret;
+
+ /* look up the key type to see if it's one of the registered kernel
+ * types */
+ ktype = key_type_lookup(type);
+ if (IS_ERR(ktype)) {
+ key_ref = ERR_PTR(-ENODEV);
+ goto error;
+ }
+
+ key_ref = ERR_PTR(-EINVAL);
+ if (!ktype->match || !ktype->instantiate)
+ goto error_2;
+
+ keyring = key_ref_to_ptr(keyring_ref);
+
+ key_check(keyring);
+
+ key_ref = ERR_PTR(-ENOTDIR);
+ if (keyring->type != &key_type_keyring)
+ goto error_2;
+
+ ret = __key_link_begin(keyring, ktype, description, &prealloc);
+ if (ret < 0)
+ goto error_2;
+
+ /* if we're going to allocate a new key, we're going to have
+ * to modify the keyring */
+ ret = key_permission(keyring_ref, KEY_WRITE);
+ if (ret < 0) {
+ key_ref = ERR_PTR(ret);
+ goto error_3;
+ }
+
+ /* if it's possible to update this type of key, search for an existing
+ * key of the same type and description in the destination keyring and
+ * update that instead if possible
+ */
+ if (ktype->update) {
+ key_ref = __keyring_search_one(keyring_ref, ktype, description,
+ 0);
+ if (!IS_ERR(key_ref))
+ goto found_matching_key;
+ }
+
+ /* if the client doesn't provide, decide on the permissions we want */
+ if (perm == KEY_PERM_UNDEF) {
+ perm = KEY_POS_VIEW | KEY_POS_SEARCH | KEY_POS_LINK | KEY_POS_SETATTR;
+ perm |= KEY_USR_VIEW | KEY_USR_SEARCH | KEY_USR_LINK | KEY_USR_SETATTR;
+
+ if (ktype->read)
+ perm |= KEY_POS_READ | KEY_USR_READ;
+
+ if (ktype == &key_type_keyring || ktype->update)
+ perm |= KEY_USR_WRITE;
+ }
+
+ /* allocate a new key */
+ key = key_alloc(ktype, description, cred->fsuid, cred->fsgid, cred,
+ perm, flags);
+ if (IS_ERR(key)) {
+ key_ref = ERR_CAST(key);
+ goto error_3;
+ }
+
+ /* instantiate it and link it into the target keyring */
+ ret = __key_instantiate_and_link(key, payload, plen, keyring, NULL,
+ &prealloc);
+ if (ret < 0) {
+ key_put(key);
+ key_ref = ERR_PTR(ret);
+ goto error_3;
+ }
+
+ key_ref = make_key_ref(key, is_key_possessed(keyring_ref));
+
+ error_3:
+ __key_link_end(keyring, ktype, prealloc);
+ error_2:
+ key_type_put(ktype);
+ error:
+ return key_ref;
+
+ found_matching_key:
+ /* we found a matching key, so we're going to try to update it
+ * - we can drop the locks first as we have the key pinned
+ */
+ __key_link_end(keyring, ktype, prealloc);
+ key_type_put(ktype);
+
+ key_ref = __key_update(key_ref, payload, plen);
+ goto error;
+}
+EXPORT_SYMBOL(key_create_or_update);
+
+/**
+ * key_update - Update a key's contents.
+ * @key_ref: The pointer (plus possession flag) to the key.
+ * @payload: The data to be used to update the key.
+ * @plen: The length of @payload.
+ *
+ * Attempt to update the contents of a key with the given payload data. The
+ * caller must be granted Write permission on the key. Negative keys can be
+ * instantiated by this method.
+ *
+ * Returns 0 on success, -EACCES if not permitted and -EOPNOTSUPP if the key
+ * type does not support updating. The key type may return other errors.
+ */
+int key_update(key_ref_t key_ref, const void *payload, size_t plen)
+{
+ struct key *key = key_ref_to_ptr(key_ref);
+ int ret;
+
+ key_check(key);
+
+ /* the key must be writable */
+ ret = key_permission(key_ref, KEY_WRITE);
+ if (ret < 0)
+ goto error;
+
+ /* attempt to update it if supported */
+ ret = -EOPNOTSUPP;
+ if (key->type->update) {
+ down_write(&key->sem);
+
+ ret = key->type->update(key, payload, plen);
+ if (ret == 0)
+ /* updating a negative key instantiates it */
+ clear_bit(KEY_FLAG_NEGATIVE, &key->flags);
+
+ up_write(&key->sem);
+ }
+
+ error:
+ return ret;
+}
+EXPORT_SYMBOL(key_update);
+
+/**
+ * key_revoke - Revoke a key.
+ * @key: The key to be revoked.
+ *
+ * Mark a key as being revoked and ask the type to free up its resources. The
+ * revocation timeout is set and the key and all its links will be
+ * automatically garbage collected after key_gc_delay amount of time if they
+ * are not manually dealt with first.
+ */
+void key_revoke(struct key *key)
+{
+ struct timespec now;
+ time_t time;
+
+ key_check(key);
+
+ /* make sure no one's trying to change or use the key when we mark it
+ * - we tell lockdep that we might nest because we might be revoking an
+ * authorisation key whilst holding the sem on a key we've just
+ * instantiated
+ */
+ down_write_nested(&key->sem, 1);
+ if (!test_and_set_bit(KEY_FLAG_REVOKED, &key->flags) &&
+ key->type->revoke)
+ key->type->revoke(key);
+
+ /* set the death time to no more than the expiry time */
+ now = current_kernel_time();
+ time = now.tv_sec;
+ if (key->revoked_at == 0 || key->revoked_at > time) {
+ key->revoked_at = time;
+ key_schedule_gc(key->revoked_at + key_gc_delay);
+ }
+
+ up_write(&key->sem);
+}
+EXPORT_SYMBOL(key_revoke);
+
+/**
+ * register_key_type - Register a type of key.
+ * @ktype: The new key type.
+ *
+ * Register a new key type.
+ *
+ * Returns 0 on success or -EEXIST if a type of this name already exists.
+ */
+int register_key_type(struct key_type *ktype)
+{
+ struct key_type *p;
+ int ret;
+
+ ret = -EEXIST;
+ down_write(&key_types_sem);
+
+ /* disallow key types with the same name */
+ list_for_each_entry(p, &key_types_list, link) {
+ if (strcmp(p->name, ktype->name) == 0)
+ goto out;
+ }
+
+ /* store the type */
+ list_add(&ktype->link, &key_types_list);
+ ret = 0;
+
+out:
+ up_write(&key_types_sem);
+ return ret;
+}
+EXPORT_SYMBOL(register_key_type);
+
+/**
+ * unregister_key_type - Unregister a type of key.
+ * @ktype: The key type.
+ *
+ * Unregister a key type and mark all the extant keys of this type as dead.
+ * Those keys of this type are then destroyed to get rid of their payloads and
+ * they and their links will be garbage collected as soon as possible.
+ */
+void unregister_key_type(struct key_type *ktype)
+{
+ struct rb_node *_n;
+ struct key *key;
+
+ down_write(&key_types_sem);
+
+ /* withdraw the key type */
+ list_del_init(&ktype->link);
+
+ /* mark all the keys of this type dead */
+ spin_lock(&key_serial_lock);
+
+ for (_n = rb_first(&key_serial_tree); _n; _n = rb_next(_n)) {
+ key = rb_entry(_n, struct key, serial_node);
+
+ if (key->type == ktype) {
+ key->type = &key_type_dead;
+ set_bit(KEY_FLAG_DEAD, &key->flags);
+ }
+ }
+
+ spin_unlock(&key_serial_lock);
+
+ /* make sure everyone revalidates their keys */
+ synchronize_rcu();
+
+ /* we should now be able to destroy the payloads of all the keys of
+ * this type with impunity */
+ spin_lock(&key_serial_lock);
+
+ for (_n = rb_first(&key_serial_tree); _n; _n = rb_next(_n)) {
+ key = rb_entry(_n, struct key, serial_node);
+
+ if (key->type == ktype) {
+ if (ktype->destroy)
+ ktype->destroy(key);
+ memset(&key->payload, KEY_DESTROY, sizeof(key->payload));
+ }
+ }
+
+ spin_unlock(&key_serial_lock);
+ up_write(&key_types_sem);
+
+ key_schedule_gc(0);
+}
+EXPORT_SYMBOL(unregister_key_type);
+
+/*
+ * Initialise the key management state.
+ */
+void __init key_init(void)
+{
+ /* allocate a slab in which we can store keys */
+ key_jar = kmem_cache_create("key_jar", sizeof(struct key),
+ 0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
+
+ /* add the special key types */
+ list_add_tail(&key_type_keyring.link, &key_types_list);
+ list_add_tail(&key_type_dead.link, &key_types_list);
+ list_add_tail(&key_type_user.link, &key_types_list);
+
+ /* record the root user tracking */
+ rb_link_node(&root_key_user.node,
+ NULL,
+ &key_user_tree.rb_node);
+
+ rb_insert_color(&root_key_user.node,
+ &key_user_tree);
+}
diff --git a/security/keys/keyctl.c b/security/keys/keyctl.c
new file mode 100644
index 00000000..eca51918
--- /dev/null
+++ b/security/keys/keyctl.c
@@ -0,0 +1,1629 @@
+/* Userspace key control operations
+ *
+ * Copyright (C) 2004-5 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/syscalls.h>
+#include <linux/keyctl.h>
+#include <linux/fs.h>
+#include <linux/capability.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <linux/vmalloc.h>
+#include <linux/security.h>
+#include <asm/uaccess.h>
+#include "internal.h"
+
+static int key_get_type_from_user(char *type,
+ const char __user *_type,
+ unsigned len)
+{
+ int ret;
+
+ ret = strncpy_from_user(type, _type, len);
+ if (ret < 0)
+ return ret;
+ if (ret == 0 || ret >= len)
+ return -EINVAL;
+ if (type[0] == '.')
+ return -EPERM;
+ type[len - 1] = '\0';
+ return 0;
+}
+
+/*
+ * Extract the description of a new key from userspace and either add it as a
+ * new key to the specified keyring or update a matching key in that keyring.
+ *
+ * The keyring must be writable so that we can attach the key to it.
+ *
+ * If successful, the new key's serial number is returned, otherwise an error
+ * code is returned.
+ */
+SYSCALL_DEFINE5(add_key, const char __user *, _type,
+ const char __user *, _description,
+ const void __user *, _payload,
+ size_t, plen,
+ key_serial_t, ringid)
+{
+ key_ref_t keyring_ref, key_ref;
+ char type[32], *description;
+ void *payload;
+ long ret;
+ bool vm;
+
+ ret = -EINVAL;
+ if (plen > 1024 * 1024 - 1)
+ goto error;
+
+ /* draw all the data into kernel space */
+ ret = key_get_type_from_user(type, _type, sizeof(type));
+ if (ret < 0)
+ goto error;
+
+ description = strndup_user(_description, PAGE_SIZE);
+ if (IS_ERR(description)) {
+ ret = PTR_ERR(description);
+ goto error;
+ }
+
+ /* pull the payload in if one was supplied */
+ payload = NULL;
+
+ vm = false;
+ if (_payload) {
+ ret = -ENOMEM;
+ payload = kmalloc(plen, GFP_KERNEL);
+ if (!payload) {
+ if (plen <= PAGE_SIZE)
+ goto error2;
+ vm = true;
+ payload = vmalloc(plen);
+ if (!payload)
+ goto error2;
+ }
+
+ ret = -EFAULT;
+ if (copy_from_user(payload, _payload, plen) != 0)
+ goto error3;
+ }
+
+ /* find the target keyring (which must be writable) */
+ keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
+ if (IS_ERR(keyring_ref)) {
+ ret = PTR_ERR(keyring_ref);
+ goto error3;
+ }
+
+ /* create or update the requested key and add it to the target
+ * keyring */
+ key_ref = key_create_or_update(keyring_ref, type, description,
+ payload, plen, KEY_PERM_UNDEF,
+ KEY_ALLOC_IN_QUOTA);
+ if (!IS_ERR(key_ref)) {
+ ret = key_ref_to_ptr(key_ref)->serial;
+ key_ref_put(key_ref);
+ }
+ else {
+ ret = PTR_ERR(key_ref);
+ }
+
+ key_ref_put(keyring_ref);
+ error3:
+ if (!vm)
+ kfree(payload);
+ else
+ vfree(payload);
+ error2:
+ kfree(description);
+ error:
+ return ret;
+}
+
+/*
+ * Search the process keyrings and keyring trees linked from those for a
+ * matching key. Keyrings must have appropriate Search permission to be
+ * searched.
+ *
+ * If a key is found, it will be attached to the destination keyring if there's
+ * one specified and the serial number of the key will be returned.
+ *
+ * If no key is found, /sbin/request-key will be invoked if _callout_info is
+ * non-NULL in an attempt to create a key. The _callout_info string will be
+ * passed to /sbin/request-key to aid with completing the request. If the
+ * _callout_info string is "" then it will be changed to "-".
+ */
+SYSCALL_DEFINE4(request_key, const char __user *, _type,
+ const char __user *, _description,
+ const char __user *, _callout_info,
+ key_serial_t, destringid)
+{
+ struct key_type *ktype;
+ struct key *key;
+ key_ref_t dest_ref;
+ size_t callout_len;
+ char type[32], *description, *callout_info;
+ long ret;
+
+ /* pull the type into kernel space */
+ ret = key_get_type_from_user(type, _type, sizeof(type));
+ if (ret < 0)
+ goto error;
+
+ /* pull the description into kernel space */
+ description = strndup_user(_description, PAGE_SIZE);
+ if (IS_ERR(description)) {
+ ret = PTR_ERR(description);
+ goto error;
+ }
+
+ /* pull the callout info into kernel space */
+ callout_info = NULL;
+ callout_len = 0;
+ if (_callout_info) {
+ callout_info = strndup_user(_callout_info, PAGE_SIZE);
+ if (IS_ERR(callout_info)) {
+ ret = PTR_ERR(callout_info);
+ goto error2;
+ }
+ callout_len = strlen(callout_info);
+ }
+
+ /* get the destination keyring if specified */
+ dest_ref = NULL;
+ if (destringid) {
+ dest_ref = lookup_user_key(destringid, KEY_LOOKUP_CREATE,
+ KEY_WRITE);
+ if (IS_ERR(dest_ref)) {
+ ret = PTR_ERR(dest_ref);
+ goto error3;
+ }
+ }
+
+ /* find the key type */
+ ktype = key_type_lookup(type);
+ if (IS_ERR(ktype)) {
+ ret = PTR_ERR(ktype);
+ goto error4;
+ }
+
+ /* do the search */
+ key = request_key_and_link(ktype, description, callout_info,
+ callout_len, NULL, key_ref_to_ptr(dest_ref),
+ KEY_ALLOC_IN_QUOTA);
+ if (IS_ERR(key)) {
+ ret = PTR_ERR(key);
+ goto error5;
+ }
+
+ /* wait for the key to finish being constructed */
+ ret = wait_for_key_construction(key, 1);
+ if (ret < 0)
+ goto error6;
+
+ ret = key->serial;
+
+error6:
+ key_put(key);
+error5:
+ key_type_put(ktype);
+error4:
+ key_ref_put(dest_ref);
+error3:
+ kfree(callout_info);
+error2:
+ kfree(description);
+error:
+ return ret;
+}
+
+/*
+ * Get the ID of the specified process keyring.
+ *
+ * The requested keyring must have search permission to be found.
+ *
+ * If successful, the ID of the requested keyring will be returned.
+ */
+long keyctl_get_keyring_ID(key_serial_t id, int create)
+{
+ key_ref_t key_ref;
+ unsigned long lflags;
+ long ret;
+
+ lflags = create ? KEY_LOOKUP_CREATE : 0;
+ key_ref = lookup_user_key(id, lflags, KEY_SEARCH);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+ goto error;
+ }
+
+ ret = key_ref_to_ptr(key_ref)->serial;
+ key_ref_put(key_ref);
+error:
+ return ret;
+}
+
+/*
+ * Join a (named) session keyring.
+ *
+ * Create and join an anonymous session keyring or join a named session
+ * keyring, creating it if necessary. A named session keyring must have Search
+ * permission for it to be joined. Session keyrings without this permit will
+ * be skipped over.
+ *
+ * If successful, the ID of the joined session keyring will be returned.
+ */
+long keyctl_join_session_keyring(const char __user *_name)
+{
+ char *name;
+ long ret;
+
+ /* fetch the name from userspace */
+ name = NULL;
+ if (_name) {
+ name = strndup_user(_name, PAGE_SIZE);
+ if (IS_ERR(name)) {
+ ret = PTR_ERR(name);
+ goto error;
+ }
+ }
+
+ /* join the session */
+ ret = join_session_keyring(name);
+ kfree(name);
+
+error:
+ return ret;
+}
+
+/*
+ * Update a key's data payload from the given data.
+ *
+ * The key must grant the caller Write permission and the key type must support
+ * updating for this to work. A negative key can be positively instantiated
+ * with this call.
+ *
+ * If successful, 0 will be returned. If the key type does not support
+ * updating, then -EOPNOTSUPP will be returned.
+ */
+long keyctl_update_key(key_serial_t id,
+ const void __user *_payload,
+ size_t plen)
+{
+ key_ref_t key_ref;
+ void *payload;
+ long ret;
+
+ ret = -EINVAL;
+ if (plen > PAGE_SIZE)
+ goto error;
+
+ /* pull the payload in if one was supplied */
+ payload = NULL;
+ if (_payload) {
+ ret = -ENOMEM;
+ payload = kmalloc(plen, GFP_KERNEL);
+ if (!payload)
+ goto error;
+
+ ret = -EFAULT;
+ if (copy_from_user(payload, _payload, plen) != 0)
+ goto error2;
+ }
+
+ /* find the target key (which must be writable) */
+ key_ref = lookup_user_key(id, 0, KEY_WRITE);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+ goto error2;
+ }
+
+ /* update the key */
+ ret = key_update(key_ref, payload, plen);
+
+ key_ref_put(key_ref);
+error2:
+ kfree(payload);
+error:
+ return ret;
+}
+
+/*
+ * Revoke a key.
+ *
+ * The key must be grant the caller Write or Setattr permission for this to
+ * work. The key type should give up its quota claim when revoked. The key
+ * and any links to the key will be automatically garbage collected after a
+ * certain amount of time (/proc/sys/kernel/keys/gc_delay).
+ *
+ * If successful, 0 is returned.
+ */
+long keyctl_revoke_key(key_serial_t id)
+{
+ key_ref_t key_ref;
+ long ret;
+
+ key_ref = lookup_user_key(id, 0, KEY_WRITE);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+ if (ret != -EACCES)
+ goto error;
+ key_ref = lookup_user_key(id, 0, KEY_SETATTR);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+ goto error;
+ }
+ }
+
+ key_revoke(key_ref_to_ptr(key_ref));
+ ret = 0;
+
+ key_ref_put(key_ref);
+error:
+ return ret;
+}
+
+/*
+ * Clear the specified keyring, creating an empty process keyring if one of the
+ * special keyring IDs is used.
+ *
+ * The keyring must grant the caller Write permission for this to work. If
+ * successful, 0 will be returned.
+ */
+long keyctl_keyring_clear(key_serial_t ringid)
+{
+ key_ref_t keyring_ref;
+ long ret;
+
+ keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
+ if (IS_ERR(keyring_ref)) {
+ ret = PTR_ERR(keyring_ref);
+ goto error;
+ }
+
+ ret = keyring_clear(key_ref_to_ptr(keyring_ref));
+
+ key_ref_put(keyring_ref);
+error:
+ return ret;
+}
+
+/*
+ * Create a link from a keyring to a key if there's no matching key in the
+ * keyring, otherwise replace the link to the matching key with a link to the
+ * new key.
+ *
+ * The key must grant the caller Link permission and the the keyring must grant
+ * the caller Write permission. Furthermore, if an additional link is created,
+ * the keyring's quota will be extended.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_keyring_link(key_serial_t id, key_serial_t ringid)
+{
+ key_ref_t keyring_ref, key_ref;
+ long ret;
+
+ keyring_ref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
+ if (IS_ERR(keyring_ref)) {
+ ret = PTR_ERR(keyring_ref);
+ goto error;
+ }
+
+ key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE, KEY_LINK);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+ goto error2;
+ }
+
+ ret = key_link(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref));
+
+ key_ref_put(key_ref);
+error2:
+ key_ref_put(keyring_ref);
+error:
+ return ret;
+}
+
+/*
+ * Unlink a key from a keyring.
+ *
+ * The keyring must grant the caller Write permission for this to work; the key
+ * itself need not grant the caller anything. If the last link to a key is
+ * removed then that key will be scheduled for destruction.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_keyring_unlink(key_serial_t id, key_serial_t ringid)
+{
+ key_ref_t keyring_ref, key_ref;
+ long ret;
+
+ keyring_ref = lookup_user_key(ringid, 0, KEY_WRITE);
+ if (IS_ERR(keyring_ref)) {
+ ret = PTR_ERR(keyring_ref);
+ goto error;
+ }
+
+ key_ref = lookup_user_key(id, KEY_LOOKUP_FOR_UNLINK, 0);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+ goto error2;
+ }
+
+ ret = key_unlink(key_ref_to_ptr(keyring_ref), key_ref_to_ptr(key_ref));
+
+ key_ref_put(key_ref);
+error2:
+ key_ref_put(keyring_ref);
+error:
+ return ret;
+}
+
+/*
+ * Return a description of a key to userspace.
+ *
+ * The key must grant the caller View permission for this to work.
+ *
+ * If there's a buffer, we place up to buflen bytes of data into it formatted
+ * in the following way:
+ *
+ * type;uid;gid;perm;description<NUL>
+ *
+ * If successful, we return the amount of description available, irrespective
+ * of how much we may have copied into the buffer.
+ */
+long keyctl_describe_key(key_serial_t keyid,
+ char __user *buffer,
+ size_t buflen)
+{
+ struct key *key, *instkey;
+ key_ref_t key_ref;
+ char *tmpbuf;
+ long ret;
+
+ key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_VIEW);
+ if (IS_ERR(key_ref)) {
+ /* viewing a key under construction is permitted if we have the
+ * authorisation token handy */
+ if (PTR_ERR(key_ref) == -EACCES) {
+ instkey = key_get_instantiation_authkey(keyid);
+ if (!IS_ERR(instkey)) {
+ key_put(instkey);
+ key_ref = lookup_user_key(keyid,
+ KEY_LOOKUP_PARTIAL,
+ 0);
+ if (!IS_ERR(key_ref))
+ goto okay;
+ }
+ }
+
+ ret = PTR_ERR(key_ref);
+ goto error;
+ }
+
+okay:
+ /* calculate how much description we're going to return */
+ ret = -ENOMEM;
+ tmpbuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
+ if (!tmpbuf)
+ goto error2;
+
+ key = key_ref_to_ptr(key_ref);
+
+ ret = snprintf(tmpbuf, PAGE_SIZE - 1,
+ "%s;%d;%d;%08x;%s",
+ key->type->name,
+ key->uid,
+ key->gid,
+ key->perm,
+ key->description ?: "");
+
+ /* include a NUL char at the end of the data */
+ if (ret > PAGE_SIZE - 1)
+ ret = PAGE_SIZE - 1;
+ tmpbuf[ret] = 0;
+ ret++;
+
+ /* consider returning the data */
+ if (buffer && buflen > 0) {
+ if (buflen > ret)
+ buflen = ret;
+
+ if (copy_to_user(buffer, tmpbuf, buflen) != 0)
+ ret = -EFAULT;
+ }
+
+ kfree(tmpbuf);
+error2:
+ key_ref_put(key_ref);
+error:
+ return ret;
+}
+
+/*
+ * Search the specified keyring and any keyrings it links to for a matching
+ * key. Only keyrings that grant the caller Search permission will be searched
+ * (this includes the starting keyring). Only keys with Search permission can
+ * be found.
+ *
+ * If successful, the found key will be linked to the destination keyring if
+ * supplied and the key has Link permission, and the found key ID will be
+ * returned.
+ */
+long keyctl_keyring_search(key_serial_t ringid,
+ const char __user *_type,
+ const char __user *_description,
+ key_serial_t destringid)
+{
+ struct key_type *ktype;
+ key_ref_t keyring_ref, key_ref, dest_ref;
+ char type[32], *description;
+ long ret;
+
+ /* pull the type and description into kernel space */
+ ret = key_get_type_from_user(type, _type, sizeof(type));
+ if (ret < 0)
+ goto error;
+
+ description = strndup_user(_description, PAGE_SIZE);
+ if (IS_ERR(description)) {
+ ret = PTR_ERR(description);
+ goto error;
+ }
+
+ /* get the keyring at which to begin the search */
+ keyring_ref = lookup_user_key(ringid, 0, KEY_SEARCH);
+ if (IS_ERR(keyring_ref)) {
+ ret = PTR_ERR(keyring_ref);
+ goto error2;
+ }
+
+ /* get the destination keyring if specified */
+ dest_ref = NULL;
+ if (destringid) {
+ dest_ref = lookup_user_key(destringid, KEY_LOOKUP_CREATE,
+ KEY_WRITE);
+ if (IS_ERR(dest_ref)) {
+ ret = PTR_ERR(dest_ref);
+ goto error3;
+ }
+ }
+
+ /* find the key type */
+ ktype = key_type_lookup(type);
+ if (IS_ERR(ktype)) {
+ ret = PTR_ERR(ktype);
+ goto error4;
+ }
+
+ /* do the search */
+ key_ref = keyring_search(keyring_ref, ktype, description);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+
+ /* treat lack or presence of a negative key the same */
+ if (ret == -EAGAIN)
+ ret = -ENOKEY;
+ goto error5;
+ }
+
+ /* link the resulting key to the destination keyring if we can */
+ if (dest_ref) {
+ ret = key_permission(key_ref, KEY_LINK);
+ if (ret < 0)
+ goto error6;
+
+ ret = key_link(key_ref_to_ptr(dest_ref), key_ref_to_ptr(key_ref));
+ if (ret < 0)
+ goto error6;
+ }
+
+ ret = key_ref_to_ptr(key_ref)->serial;
+
+error6:
+ key_ref_put(key_ref);
+error5:
+ key_type_put(ktype);
+error4:
+ key_ref_put(dest_ref);
+error3:
+ key_ref_put(keyring_ref);
+error2:
+ kfree(description);
+error:
+ return ret;
+}
+
+/*
+ * Read a key's payload.
+ *
+ * The key must either grant the caller Read permission, or it must grant the
+ * caller Search permission when searched for from the process keyrings.
+ *
+ * If successful, we place up to buflen bytes of data into the buffer, if one
+ * is provided, and return the amount of data that is available in the key,
+ * irrespective of how much we copied into the buffer.
+ */
+long keyctl_read_key(key_serial_t keyid, char __user *buffer, size_t buflen)
+{
+ struct key *key;
+ key_ref_t key_ref;
+ long ret;
+
+ /* find the key first */
+ key_ref = lookup_user_key(keyid, 0, 0);
+ if (IS_ERR(key_ref)) {
+ ret = -ENOKEY;
+ goto error;
+ }
+
+ key = key_ref_to_ptr(key_ref);
+
+ /* see if we can read it directly */
+ ret = key_permission(key_ref, KEY_READ);
+ if (ret == 0)
+ goto can_read_key;
+ if (ret != -EACCES)
+ goto error;
+
+ /* we can't; see if it's searchable from this process's keyrings
+ * - we automatically take account of the fact that it may be
+ * dangling off an instantiation key
+ */
+ if (!is_key_possessed(key_ref)) {
+ ret = -EACCES;
+ goto error2;
+ }
+
+ /* the key is probably readable - now try to read it */
+can_read_key:
+ ret = key_validate(key);
+ if (ret == 0) {
+ ret = -EOPNOTSUPP;
+ if (key->type->read) {
+ /* read the data with the semaphore held (since we
+ * might sleep) */
+ down_read(&key->sem);
+ ret = key->type->read(key, buffer, buflen);
+ up_read(&key->sem);
+ }
+ }
+
+error2:
+ key_put(key);
+error:
+ return ret;
+}
+
+/*
+ * Change the ownership of a key
+ *
+ * The key must grant the caller Setattr permission for this to work, though
+ * the key need not be fully instantiated yet. For the UID to be changed, or
+ * for the GID to be changed to a group the caller is not a member of, the
+ * caller must have sysadmin capability. If either uid or gid is -1 then that
+ * attribute is not changed.
+ *
+ * If the UID is to be changed, the new user must have sufficient quota to
+ * accept the key. The quota deduction will be removed from the old user to
+ * the new user should the attribute be changed.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_chown_key(key_serial_t id, uid_t uid, gid_t gid)
+{
+ struct key_user *newowner, *zapowner = NULL;
+ struct key *key;
+ key_ref_t key_ref;
+ long ret;
+
+ ret = 0;
+ if (uid == (uid_t) -1 && gid == (gid_t) -1)
+ goto error;
+
+ key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
+ KEY_SETATTR);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+ goto error;
+ }
+
+ key = key_ref_to_ptr(key_ref);
+
+ /* make the changes with the locks held to prevent chown/chown races */
+ ret = -EACCES;
+ down_write(&key->sem);
+
+ if (!capable(CAP_SYS_ADMIN)) {
+ /* only the sysadmin can chown a key to some other UID */
+ if (uid != (uid_t) -1 && key->uid != uid)
+ goto error_put;
+
+ /* only the sysadmin can set the key's GID to a group other
+ * than one of those that the current process subscribes to */
+ if (gid != (gid_t) -1 && gid != key->gid && !in_group_p(gid))
+ goto error_put;
+ }
+
+ /* change the UID */
+ if (uid != (uid_t) -1 && uid != key->uid) {
+ ret = -ENOMEM;
+ newowner = key_user_lookup(uid, current_user_ns());
+ if (!newowner)
+ goto error_put;
+
+ /* transfer the quota burden to the new user */
+ if (test_bit(KEY_FLAG_IN_QUOTA, &key->flags)) {
+ unsigned maxkeys = (uid == 0) ?
+ key_quota_root_maxkeys : key_quota_maxkeys;
+ unsigned maxbytes = (uid == 0) ?
+ key_quota_root_maxbytes : key_quota_maxbytes;
+
+ spin_lock(&newowner->lock);
+ if (newowner->qnkeys + 1 >= maxkeys ||
+ newowner->qnbytes + key->quotalen >= maxbytes ||
+ newowner->qnbytes + key->quotalen <
+ newowner->qnbytes)
+ goto quota_overrun;
+
+ newowner->qnkeys++;
+ newowner->qnbytes += key->quotalen;
+ spin_unlock(&newowner->lock);
+
+ spin_lock(&key->user->lock);
+ key->user->qnkeys--;
+ key->user->qnbytes -= key->quotalen;
+ spin_unlock(&key->user->lock);
+ }
+
+ atomic_dec(&key->user->nkeys);
+ atomic_inc(&newowner->nkeys);
+
+ if (test_bit(KEY_FLAG_INSTANTIATED, &key->flags)) {
+ atomic_dec(&key->user->nikeys);
+ atomic_inc(&newowner->nikeys);
+ }
+
+ zapowner = key->user;
+ key->user = newowner;
+ key->uid = uid;
+ }
+
+ /* change the GID */
+ if (gid != (gid_t) -1)
+ key->gid = gid;
+
+ ret = 0;
+
+error_put:
+ up_write(&key->sem);
+ key_put(key);
+ if (zapowner)
+ key_user_put(zapowner);
+error:
+ return ret;
+
+quota_overrun:
+ spin_unlock(&newowner->lock);
+ zapowner = newowner;
+ ret = -EDQUOT;
+ goto error_put;
+}
+
+/*
+ * Change the permission mask on a key.
+ *
+ * The key must grant the caller Setattr permission for this to work, though
+ * the key need not be fully instantiated yet. If the caller does not have
+ * sysadmin capability, it may only change the permission on keys that it owns.
+ */
+long keyctl_setperm_key(key_serial_t id, key_perm_t perm)
+{
+ struct key *key;
+ key_ref_t key_ref;
+ long ret;
+
+ ret = -EINVAL;
+ if (perm & ~(KEY_POS_ALL | KEY_USR_ALL | KEY_GRP_ALL | KEY_OTH_ALL))
+ goto error;
+
+ key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
+ KEY_SETATTR);
+ if (IS_ERR(key_ref)) {
+ ret = PTR_ERR(key_ref);
+ goto error;
+ }
+
+ key = key_ref_to_ptr(key_ref);
+
+ /* make the changes with the locks held to prevent chown/chmod races */
+ ret = -EACCES;
+ down_write(&key->sem);
+
+ /* if we're not the sysadmin, we can only change a key that we own */
+ if (capable(CAP_SYS_ADMIN) || key->uid == current_fsuid()) {
+ key->perm = perm;
+ ret = 0;
+ }
+
+ up_write(&key->sem);
+ key_put(key);
+error:
+ return ret;
+}
+
+/*
+ * Get the destination keyring for instantiation and check that the caller has
+ * Write permission on it.
+ */
+static long get_instantiation_keyring(key_serial_t ringid,
+ struct request_key_auth *rka,
+ struct key **_dest_keyring)
+{
+ key_ref_t dkref;
+
+ *_dest_keyring = NULL;
+
+ /* just return a NULL pointer if we weren't asked to make a link */
+ if (ringid == 0)
+ return 0;
+
+ /* if a specific keyring is nominated by ID, then use that */
+ if (ringid > 0) {
+ dkref = lookup_user_key(ringid, KEY_LOOKUP_CREATE, KEY_WRITE);
+ if (IS_ERR(dkref))
+ return PTR_ERR(dkref);
+ *_dest_keyring = key_ref_to_ptr(dkref);
+ return 0;
+ }
+
+ if (ringid == KEY_SPEC_REQKEY_AUTH_KEY)
+ return -EINVAL;
+
+ /* otherwise specify the destination keyring recorded in the
+ * authorisation key (any KEY_SPEC_*_KEYRING) */
+ if (ringid >= KEY_SPEC_REQUESTOR_KEYRING) {
+ *_dest_keyring = key_get(rka->dest_keyring);
+ return 0;
+ }
+
+ return -ENOKEY;
+}
+
+/*
+ * Change the request_key authorisation key on the current process.
+ */
+static int keyctl_change_reqkey_auth(struct key *key)
+{
+ struct cred *new;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ key_put(new->request_key_auth);
+ new->request_key_auth = key_get(key);
+
+ return commit_creds(new);
+}
+
+/*
+ * Copy the iovec data from userspace
+ */
+static long copy_from_user_iovec(void *buffer, const struct iovec *iov,
+ unsigned ioc)
+{
+ for (; ioc > 0; ioc--) {
+ if (copy_from_user(buffer, iov->iov_base, iov->iov_len) != 0)
+ return -EFAULT;
+ buffer += iov->iov_len;
+ iov++;
+ }
+ return 0;
+}
+
+/*
+ * Instantiate a key with the specified payload and link the key into the
+ * destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority). No other permissions are required.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_instantiate_key_common(key_serial_t id,
+ const struct iovec *payload_iov,
+ unsigned ioc,
+ size_t plen,
+ key_serial_t ringid)
+{
+ const struct cred *cred = current_cred();
+ struct request_key_auth *rka;
+ struct key *instkey, *dest_keyring;
+ void *payload;
+ long ret;
+ bool vm = false;
+
+ kenter("%d,,%zu,%d", id, plen, ringid);
+
+ ret = -EINVAL;
+ if (plen > 1024 * 1024 - 1)
+ goto error;
+
+ /* the appropriate instantiation authorisation key must have been
+ * assumed before calling this */
+ ret = -EPERM;
+ instkey = cred->request_key_auth;
+ if (!instkey)
+ goto error;
+
+ rka = instkey->payload.data;
+ if (rka->target_key->serial != id)
+ goto error;
+
+ /* pull the payload in if one was supplied */
+ payload = NULL;
+
+ if (payload_iov) {
+ ret = -ENOMEM;
+ payload = kmalloc(plen, GFP_KERNEL);
+ if (!payload) {
+ if (plen <= PAGE_SIZE)
+ goto error;
+ vm = true;
+ payload = vmalloc(plen);
+ if (!payload)
+ goto error;
+ }
+
+ ret = copy_from_user_iovec(payload, payload_iov, ioc);
+ if (ret < 0)
+ goto error2;
+ }
+
+ /* find the destination keyring amongst those belonging to the
+ * requesting task */
+ ret = get_instantiation_keyring(ringid, rka, &dest_keyring);
+ if (ret < 0)
+ goto error2;
+
+ /* instantiate the key and link it into a keyring */
+ ret = key_instantiate_and_link(rka->target_key, payload, plen,
+ dest_keyring, instkey);
+
+ key_put(dest_keyring);
+
+ /* discard the assumed authority if it's just been disabled by
+ * instantiation of the key */
+ if (ret == 0)
+ keyctl_change_reqkey_auth(NULL);
+
+error2:
+ if (!vm)
+ kfree(payload);
+ else
+ vfree(payload);
+error:
+ return ret;
+}
+
+/*
+ * Instantiate a key with the specified payload and link the key into the
+ * destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority). No other permissions are required.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_instantiate_key(key_serial_t id,
+ const void __user *_payload,
+ size_t plen,
+ key_serial_t ringid)
+{
+ if (_payload && plen) {
+ struct iovec iov[1] = {
+ [0].iov_base = (void __user *)_payload,
+ [0].iov_len = plen
+ };
+
+ return keyctl_instantiate_key_common(id, iov, 1, plen, ringid);
+ }
+
+ return keyctl_instantiate_key_common(id, NULL, 0, 0, ringid);
+}
+
+/*
+ * Instantiate a key with the specified multipart payload and link the key into
+ * the destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority). No other permissions are required.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_instantiate_key_iov(key_serial_t id,
+ const struct iovec __user *_payload_iov,
+ unsigned ioc,
+ key_serial_t ringid)
+{
+ struct iovec iovstack[UIO_FASTIOV], *iov = iovstack;
+ long ret;
+
+ if (_payload_iov == 0 || ioc == 0)
+ goto no_payload;
+
+ ret = rw_copy_check_uvector(WRITE, _payload_iov, ioc,
+ ARRAY_SIZE(iovstack), iovstack, &iov);
+ if (ret < 0)
+ return ret;
+ if (ret == 0)
+ goto no_payload_free;
+
+ ret = keyctl_instantiate_key_common(id, iov, ioc, ret, ringid);
+
+ if (iov != iovstack)
+ kfree(iov);
+ return ret;
+
+no_payload_free:
+ if (iov != iovstack)
+ kfree(iov);
+no_payload:
+ return keyctl_instantiate_key_common(id, NULL, 0, 0, ringid);
+}
+
+/*
+ * Negatively instantiate the key with the given timeout (in seconds) and link
+ * the key into the destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority). No other permissions are required.
+ *
+ * The key and any links to the key will be automatically garbage collected
+ * after the timeout expires.
+ *
+ * Negative keys are used to rate limit repeated request_key() calls by causing
+ * them to return -ENOKEY until the negative key expires.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_negate_key(key_serial_t id, unsigned timeout, key_serial_t ringid)
+{
+ return keyctl_reject_key(id, timeout, ENOKEY, ringid);
+}
+
+/*
+ * Negatively instantiate the key with the given timeout (in seconds) and error
+ * code and link the key into the destination keyring if one is given.
+ *
+ * The caller must have the appropriate instantiation permit set for this to
+ * work (see keyctl_assume_authority). No other permissions are required.
+ *
+ * The key and any links to the key will be automatically garbage collected
+ * after the timeout expires.
+ *
+ * Negative keys are used to rate limit repeated request_key() calls by causing
+ * them to return the specified error code until the negative key expires.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_reject_key(key_serial_t id, unsigned timeout, unsigned error,
+ key_serial_t ringid)
+{
+ const struct cred *cred = current_cred();
+ struct request_key_auth *rka;
+ struct key *instkey, *dest_keyring;
+ long ret;
+
+ kenter("%d,%u,%u,%d", id, timeout, error, ringid);
+
+ /* must be a valid error code and mustn't be a kernel special */
+ if (error <= 0 ||
+ error >= MAX_ERRNO ||
+ error == ERESTARTSYS ||
+ error == ERESTARTNOINTR ||
+ error == ERESTARTNOHAND ||
+ error == ERESTART_RESTARTBLOCK)
+ return -EINVAL;
+
+ /* the appropriate instantiation authorisation key must have been
+ * assumed before calling this */
+ ret = -EPERM;
+ instkey = cred->request_key_auth;
+ if (!instkey)
+ goto error;
+
+ rka = instkey->payload.data;
+ if (rka->target_key->serial != id)
+ goto error;
+
+ /* find the destination keyring if present (which must also be
+ * writable) */
+ ret = get_instantiation_keyring(ringid, rka, &dest_keyring);
+ if (ret < 0)
+ goto error;
+
+ /* instantiate the key and link it into a keyring */
+ ret = key_reject_and_link(rka->target_key, timeout, error,
+ dest_keyring, instkey);
+
+ key_put(dest_keyring);
+
+ /* discard the assumed authority if it's just been disabled by
+ * instantiation of the key */
+ if (ret == 0)
+ keyctl_change_reqkey_auth(NULL);
+
+error:
+ return ret;
+}
+
+/*
+ * Read or set the default keyring in which request_key() will cache keys and
+ * return the old setting.
+ *
+ * If a process keyring is specified then this will be created if it doesn't
+ * yet exist. The old setting will be returned if successful.
+ */
+long keyctl_set_reqkey_keyring(int reqkey_defl)
+{
+ struct cred *new;
+ int ret, old_setting;
+
+ old_setting = current_cred_xxx(jit_keyring);
+
+ if (reqkey_defl == KEY_REQKEY_DEFL_NO_CHANGE)
+ return old_setting;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ switch (reqkey_defl) {
+ case KEY_REQKEY_DEFL_THREAD_KEYRING:
+ ret = install_thread_keyring_to_cred(new);
+ if (ret < 0)
+ goto error;
+ goto set;
+
+ case KEY_REQKEY_DEFL_PROCESS_KEYRING:
+ ret = install_process_keyring_to_cred(new);
+ if (ret < 0) {
+ if (ret != -EEXIST)
+ goto error;
+ ret = 0;
+ }
+ goto set;
+
+ case KEY_REQKEY_DEFL_DEFAULT:
+ case KEY_REQKEY_DEFL_SESSION_KEYRING:
+ case KEY_REQKEY_DEFL_USER_KEYRING:
+ case KEY_REQKEY_DEFL_USER_SESSION_KEYRING:
+ case KEY_REQKEY_DEFL_REQUESTOR_KEYRING:
+ goto set;
+
+ case KEY_REQKEY_DEFL_NO_CHANGE:
+ case KEY_REQKEY_DEFL_GROUP_KEYRING:
+ default:
+ ret = -EINVAL;
+ goto error;
+ }
+
+set:
+ new->jit_keyring = reqkey_defl;
+ commit_creds(new);
+ return old_setting;
+error:
+ abort_creds(new);
+ return ret;
+}
+
+/*
+ * Set or clear the timeout on a key.
+ *
+ * Either the key must grant the caller Setattr permission or else the caller
+ * must hold an instantiation authorisation token for the key.
+ *
+ * The timeout is either 0 to clear the timeout, or a number of seconds from
+ * the current time. The key and any links to the key will be automatically
+ * garbage collected after the timeout expires.
+ *
+ * If successful, 0 is returned.
+ */
+long keyctl_set_timeout(key_serial_t id, unsigned timeout)
+{
+ struct timespec now;
+ struct key *key, *instkey;
+ key_ref_t key_ref;
+ time_t expiry;
+ long ret;
+
+ key_ref = lookup_user_key(id, KEY_LOOKUP_CREATE | KEY_LOOKUP_PARTIAL,
+ KEY_SETATTR);
+ if (IS_ERR(key_ref)) {
+ /* setting the timeout on a key under construction is permitted
+ * if we have the authorisation token handy */
+ if (PTR_ERR(key_ref) == -EACCES) {
+ instkey = key_get_instantiation_authkey(id);
+ if (!IS_ERR(instkey)) {
+ key_put(instkey);
+ key_ref = lookup_user_key(id,
+ KEY_LOOKUP_PARTIAL,
+ 0);
+ if (!IS_ERR(key_ref))
+ goto okay;
+ }
+ }
+
+ ret = PTR_ERR(key_ref);
+ goto error;
+ }
+
+okay:
+ key = key_ref_to_ptr(key_ref);
+
+ /* make the changes with the locks held to prevent races */
+ down_write(&key->sem);
+
+ expiry = 0;
+ if (timeout > 0) {
+ now = current_kernel_time();
+ expiry = now.tv_sec + timeout;
+ }
+
+ key->expiry = expiry;
+ key_schedule_gc(key->expiry + key_gc_delay);
+
+ up_write(&key->sem);
+ key_put(key);
+
+ ret = 0;
+error:
+ return ret;
+}
+
+/*
+ * Assume (or clear) the authority to instantiate the specified key.
+ *
+ * This sets the authoritative token currently in force for key instantiation.
+ * This must be done for a key to be instantiated. It has the effect of making
+ * available all the keys from the caller of the request_key() that created a
+ * key to request_key() calls made by the caller of this function.
+ *
+ * The caller must have the instantiation key in their process keyrings with a
+ * Search permission grant available to the caller.
+ *
+ * If the ID given is 0, then the setting will be cleared and 0 returned.
+ *
+ * If the ID given has a matching an authorisation key, then that key will be
+ * set and its ID will be returned. The authorisation key can be read to get
+ * the callout information passed to request_key().
+ */
+long keyctl_assume_authority(key_serial_t id)
+{
+ struct key *authkey;
+ long ret;
+
+ /* special key IDs aren't permitted */
+ ret = -EINVAL;
+ if (id < 0)
+ goto error;
+
+ /* we divest ourselves of authority if given an ID of 0 */
+ if (id == 0) {
+ ret = keyctl_change_reqkey_auth(NULL);
+ goto error;
+ }
+
+ /* attempt to assume the authority temporarily granted to us whilst we
+ * instantiate the specified key
+ * - the authorisation key must be in the current task's keyrings
+ * somewhere
+ */
+ authkey = key_get_instantiation_authkey(id);
+ if (IS_ERR(authkey)) {
+ ret = PTR_ERR(authkey);
+ goto error;
+ }
+
+ ret = keyctl_change_reqkey_auth(authkey);
+ if (ret < 0)
+ goto error;
+ key_put(authkey);
+
+ ret = authkey->serial;
+error:
+ return ret;
+}
+
+/*
+ * Get a key's the LSM security label.
+ *
+ * The key must grant the caller View permission for this to work.
+ *
+ * If there's a buffer, then up to buflen bytes of data will be placed into it.
+ *
+ * If successful, the amount of information available will be returned,
+ * irrespective of how much was copied (including the terminal NUL).
+ */
+long keyctl_get_security(key_serial_t keyid,
+ char __user *buffer,
+ size_t buflen)
+{
+ struct key *key, *instkey;
+ key_ref_t key_ref;
+ char *context;
+ long ret;
+
+ key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, KEY_VIEW);
+ if (IS_ERR(key_ref)) {
+ if (PTR_ERR(key_ref) != -EACCES)
+ return PTR_ERR(key_ref);
+
+ /* viewing a key under construction is also permitted if we
+ * have the authorisation token handy */
+ instkey = key_get_instantiation_authkey(keyid);
+ if (IS_ERR(instkey))
+ return PTR_ERR(instkey);
+ key_put(instkey);
+
+ key_ref = lookup_user_key(keyid, KEY_LOOKUP_PARTIAL, 0);
+ if (IS_ERR(key_ref))
+ return PTR_ERR(key_ref);
+ }
+
+ key = key_ref_to_ptr(key_ref);
+ ret = security_key_getsecurity(key, &context);
+ if (ret == 0) {
+ /* if no information was returned, give userspace an empty
+ * string */
+ ret = 1;
+ if (buffer && buflen > 0 &&
+ copy_to_user(buffer, "", 1) != 0)
+ ret = -EFAULT;
+ } else if (ret > 0) {
+ /* return as much data as there's room for */
+ if (buffer && buflen > 0) {
+ if (buflen > ret)
+ buflen = ret;
+
+ if (copy_to_user(buffer, context, buflen) != 0)
+ ret = -EFAULT;
+ }
+
+ kfree(context);
+ }
+
+ key_ref_put(key_ref);
+ return ret;
+}
+
+/*
+ * Attempt to install the calling process's session keyring on the process's
+ * parent process.
+ *
+ * The keyring must exist and must grant the caller LINK permission, and the
+ * parent process must be single-threaded and must have the same effective
+ * ownership as this process and mustn't be SUID/SGID.
+ *
+ * The keyring will be emplaced on the parent when it next resumes userspace.
+ *
+ * If successful, 0 will be returned.
+ */
+long keyctl_session_to_parent(void)
+{
+#ifdef TIF_NOTIFY_RESUME
+ struct task_struct *me, *parent;
+ const struct cred *mycred, *pcred;
+ struct cred *cred, *oldcred;
+ key_ref_t keyring_r;
+ int ret;
+
+ keyring_r = lookup_user_key(KEY_SPEC_SESSION_KEYRING, 0, KEY_LINK);
+ if (IS_ERR(keyring_r))
+ return PTR_ERR(keyring_r);
+
+ /* our parent is going to need a new cred struct, a new tgcred struct
+ * and new security data, so we allocate them here to prevent ENOMEM in
+ * our parent */
+ ret = -ENOMEM;
+ cred = cred_alloc_blank();
+ if (!cred)
+ goto error_keyring;
+
+ cred->tgcred->session_keyring = key_ref_to_ptr(keyring_r);
+ keyring_r = NULL;
+
+ me = current;
+ rcu_read_lock();
+ write_lock_irq(&tasklist_lock);
+
+ parent = me->real_parent;
+ ret = -EPERM;
+
+ /* the parent mustn't be init and mustn't be a kernel thread */
+ if (parent->pid <= 1 || !parent->mm)
+ goto not_permitted;
+
+ /* the parent must be single threaded */
+ if (!thread_group_empty(parent))
+ goto not_permitted;
+
+ /* the parent and the child must have different session keyrings or
+ * there's no point */
+ mycred = current_cred();
+ pcred = __task_cred(parent);
+ if (mycred == pcred ||
+ mycred->tgcred->session_keyring == pcred->tgcred->session_keyring)
+ goto already_same;
+
+ /* the parent must have the same effective ownership and mustn't be
+ * SUID/SGID */
+ if (pcred->uid != mycred->euid ||
+ pcred->euid != mycred->euid ||
+ pcred->suid != mycred->euid ||
+ pcred->gid != mycred->egid ||
+ pcred->egid != mycred->egid ||
+ pcred->sgid != mycred->egid)
+ goto not_permitted;
+
+ /* the keyrings must have the same UID */
+ if ((pcred->tgcred->session_keyring &&
+ pcred->tgcred->session_keyring->uid != mycred->euid) ||
+ mycred->tgcred->session_keyring->uid != mycred->euid)
+ goto not_permitted;
+
+ /* if there's an already pending keyring replacement, then we replace
+ * that */
+ oldcred = parent->replacement_session_keyring;
+
+ /* the replacement session keyring is applied just prior to userspace
+ * restarting */
+ parent->replacement_session_keyring = cred;
+ cred = NULL;
+ set_ti_thread_flag(task_thread_info(parent), TIF_NOTIFY_RESUME);
+
+ write_unlock_irq(&tasklist_lock);
+ rcu_read_unlock();
+ if (oldcred)
+ put_cred(oldcred);
+ return 0;
+
+already_same:
+ ret = 0;
+not_permitted:
+ write_unlock_irq(&tasklist_lock);
+ rcu_read_unlock();
+ put_cred(cred);
+ return ret;
+
+error_keyring:
+ key_ref_put(keyring_r);
+ return ret;
+
+#else /* !TIF_NOTIFY_RESUME */
+ /*
+ * To be removed when TIF_NOTIFY_RESUME has been implemented on
+ * m68k/xtensa
+ */
+#warning TIF_NOTIFY_RESUME not implemented
+ return -EOPNOTSUPP;
+#endif /* !TIF_NOTIFY_RESUME */
+}
+
+/*
+ * The key control system call
+ */
+SYSCALL_DEFINE5(keyctl, int, option, unsigned long, arg2, unsigned long, arg3,
+ unsigned long, arg4, unsigned long, arg5)
+{
+ switch (option) {
+ case KEYCTL_GET_KEYRING_ID:
+ return keyctl_get_keyring_ID((key_serial_t) arg2,
+ (int) arg3);
+
+ case KEYCTL_JOIN_SESSION_KEYRING:
+ return keyctl_join_session_keyring((const char __user *) arg2);
+
+ case KEYCTL_UPDATE:
+ return keyctl_update_key((key_serial_t) arg2,
+ (const void __user *) arg3,
+ (size_t) arg4);
+
+ case KEYCTL_REVOKE:
+ return keyctl_revoke_key((key_serial_t) arg2);
+
+ case KEYCTL_DESCRIBE:
+ return keyctl_describe_key((key_serial_t) arg2,
+ (char __user *) arg3,
+ (unsigned) arg4);
+
+ case KEYCTL_CLEAR:
+ return keyctl_keyring_clear((key_serial_t) arg2);
+
+ case KEYCTL_LINK:
+ return keyctl_keyring_link((key_serial_t) arg2,
+ (key_serial_t) arg3);
+
+ case KEYCTL_UNLINK:
+ return keyctl_keyring_unlink((key_serial_t) arg2,
+ (key_serial_t) arg3);
+
+ case KEYCTL_SEARCH:
+ return keyctl_keyring_search((key_serial_t) arg2,
+ (const char __user *) arg3,
+ (const char __user *) arg4,
+ (key_serial_t) arg5);
+
+ case KEYCTL_READ:
+ return keyctl_read_key((key_serial_t) arg2,
+ (char __user *) arg3,
+ (size_t) arg4);
+
+ case KEYCTL_CHOWN:
+ return keyctl_chown_key((key_serial_t) arg2,
+ (uid_t) arg3,
+ (gid_t) arg4);
+
+ case KEYCTL_SETPERM:
+ return keyctl_setperm_key((key_serial_t) arg2,
+ (key_perm_t) arg3);
+
+ case KEYCTL_INSTANTIATE:
+ return keyctl_instantiate_key((key_serial_t) arg2,
+ (const void __user *) arg3,
+ (size_t) arg4,
+ (key_serial_t) arg5);
+
+ case KEYCTL_NEGATE:
+ return keyctl_negate_key((key_serial_t) arg2,
+ (unsigned) arg3,
+ (key_serial_t) arg4);
+
+ case KEYCTL_SET_REQKEY_KEYRING:
+ return keyctl_set_reqkey_keyring(arg2);
+
+ case KEYCTL_SET_TIMEOUT:
+ return keyctl_set_timeout((key_serial_t) arg2,
+ (unsigned) arg3);
+
+ case KEYCTL_ASSUME_AUTHORITY:
+ return keyctl_assume_authority((key_serial_t) arg2);
+
+ case KEYCTL_GET_SECURITY:
+ return keyctl_get_security((key_serial_t) arg2,
+ (char __user *) arg3,
+ (size_t) arg4);
+
+ case KEYCTL_SESSION_TO_PARENT:
+ return keyctl_session_to_parent();
+
+ case KEYCTL_REJECT:
+ return keyctl_reject_key((key_serial_t) arg2,
+ (unsigned) arg3,
+ (unsigned) arg4,
+ (key_serial_t) arg5);
+
+ case KEYCTL_INSTANTIATE_IOV:
+ return keyctl_instantiate_key_iov(
+ (key_serial_t) arg2,
+ (const struct iovec __user *) arg3,
+ (unsigned) arg4,
+ (key_serial_t) arg5);
+
+ default:
+ return -EOPNOTSUPP;
+ }
+}
diff --git a/security/keys/keyring.c b/security/keys/keyring.c
new file mode 100644
index 00000000..a06ffab3
--- /dev/null
+++ b/security/keys/keyring.c
@@ -0,0 +1,1226 @@
+/* Keyring handling
+ *
+ * Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/slab.h>
+#include <linux/security.h>
+#include <linux/seq_file.h>
+#include <linux/err.h>
+#include <keys/keyring-type.h>
+#include <linux/uaccess.h>
+#include "internal.h"
+
+#define rcu_dereference_locked_keyring(keyring) \
+ (rcu_dereference_protected( \
+ (keyring)->payload.subscriptions, \
+ rwsem_is_locked((struct rw_semaphore *)&(keyring)->sem)))
+
+#define KEY_LINK_FIXQUOTA 1UL
+
+/*
+ * When plumbing the depths of the key tree, this sets a hard limit
+ * set on how deep we're willing to go.
+ */
+#define KEYRING_SEARCH_MAX_DEPTH 6
+
+/*
+ * We keep all named keyrings in a hash to speed looking them up.
+ */
+#define KEYRING_NAME_HASH_SIZE (1 << 5)
+
+static struct list_head keyring_name_hash[KEYRING_NAME_HASH_SIZE];
+static DEFINE_RWLOCK(keyring_name_lock);
+
+static inline unsigned keyring_hash(const char *desc)
+{
+ unsigned bucket = 0;
+
+ for (; *desc; desc++)
+ bucket += (unsigned char)*desc;
+
+ return bucket & (KEYRING_NAME_HASH_SIZE - 1);
+}
+
+/*
+ * The keyring key type definition. Keyrings are simply keys of this type and
+ * can be treated as ordinary keys in addition to having their own special
+ * operations.
+ */
+static int keyring_instantiate(struct key *keyring,
+ const void *data, size_t datalen);
+static int keyring_match(const struct key *keyring, const void *criterion);
+static void keyring_revoke(struct key *keyring);
+static void keyring_destroy(struct key *keyring);
+static void keyring_describe(const struct key *keyring, struct seq_file *m);
+static long keyring_read(const struct key *keyring,
+ char __user *buffer, size_t buflen);
+
+struct key_type key_type_keyring = {
+ .name = "keyring",
+ .def_datalen = sizeof(struct keyring_list),
+ .instantiate = keyring_instantiate,
+ .match = keyring_match,
+ .revoke = keyring_revoke,
+ .destroy = keyring_destroy,
+ .describe = keyring_describe,
+ .read = keyring_read,
+};
+EXPORT_SYMBOL(key_type_keyring);
+
+/*
+ * Semaphore to serialise link/link calls to prevent two link calls in parallel
+ * introducing a cycle.
+ */
+static DECLARE_RWSEM(keyring_serialise_link_sem);
+
+/*
+ * Publish the name of a keyring so that it can be found by name (if it has
+ * one).
+ */
+static void keyring_publish_name(struct key *keyring)
+{
+ int bucket;
+
+ if (keyring->description) {
+ bucket = keyring_hash(keyring->description);
+
+ write_lock(&keyring_name_lock);
+
+ if (!keyring_name_hash[bucket].next)
+ INIT_LIST_HEAD(&keyring_name_hash[bucket]);
+
+ list_add_tail(&keyring->type_data.link,
+ &keyring_name_hash[bucket]);
+
+ write_unlock(&keyring_name_lock);
+ }
+}
+
+/*
+ * Initialise a keyring.
+ *
+ * Returns 0 on success, -EINVAL if given any data.
+ */
+static int keyring_instantiate(struct key *keyring,
+ const void *data, size_t datalen)
+{
+ int ret;
+
+ ret = -EINVAL;
+ if (datalen == 0) {
+ /* make the keyring available by name if it has one */
+ keyring_publish_name(keyring);
+ ret = 0;
+ }
+
+ return ret;
+}
+
+/*
+ * Match keyrings on their name
+ */
+static int keyring_match(const struct key *keyring, const void *description)
+{
+ return keyring->description &&
+ strcmp(keyring->description, description) == 0;
+}
+
+/*
+ * Clean up a keyring when it is destroyed. Unpublish its name if it had one
+ * and dispose of its data.
+ */
+static void keyring_destroy(struct key *keyring)
+{
+ struct keyring_list *klist;
+ int loop;
+
+ if (keyring->description) {
+ write_lock(&keyring_name_lock);
+
+ if (keyring->type_data.link.next != NULL &&
+ !list_empty(&keyring->type_data.link))
+ list_del(&keyring->type_data.link);
+
+ write_unlock(&keyring_name_lock);
+ }
+
+ klist = rcu_dereference_check(keyring->payload.subscriptions,
+ rcu_read_lock_held() ||
+ atomic_read(&keyring->usage) == 0);
+ if (klist) {
+ for (loop = klist->nkeys - 1; loop >= 0; loop--)
+ key_put(klist->keys[loop]);
+ kfree(klist);
+ }
+}
+
+/*
+ * Describe a keyring for /proc.
+ */
+static void keyring_describe(const struct key *keyring, struct seq_file *m)
+{
+ struct keyring_list *klist;
+
+ if (keyring->description)
+ seq_puts(m, keyring->description);
+ else
+ seq_puts(m, "[anon]");
+
+ if (key_is_instantiated(keyring)) {
+ rcu_read_lock();
+ klist = rcu_dereference(keyring->payload.subscriptions);
+ if (klist)
+ seq_printf(m, ": %u/%u", klist->nkeys, klist->maxkeys);
+ else
+ seq_puts(m, ": empty");
+ rcu_read_unlock();
+ }
+}
+
+/*
+ * Read a list of key IDs from the keyring's contents in binary form
+ *
+ * The keyring's semaphore is read-locked by the caller.
+ */
+static long keyring_read(const struct key *keyring,
+ char __user *buffer, size_t buflen)
+{
+ struct keyring_list *klist;
+ struct key *key;
+ size_t qty, tmp;
+ int loop, ret;
+
+ ret = 0;
+ klist = rcu_dereference_locked_keyring(keyring);
+ if (klist) {
+ /* calculate how much data we could return */
+ qty = klist->nkeys * sizeof(key_serial_t);
+
+ if (buffer && buflen > 0) {
+ if (buflen > qty)
+ buflen = qty;
+
+ /* copy the IDs of the subscribed keys into the
+ * buffer */
+ ret = -EFAULT;
+
+ for (loop = 0; loop < klist->nkeys; loop++) {
+ key = klist->keys[loop];
+
+ tmp = sizeof(key_serial_t);
+ if (tmp > buflen)
+ tmp = buflen;
+
+ if (copy_to_user(buffer,
+ &key->serial,
+ tmp) != 0)
+ goto error;
+
+ buflen -= tmp;
+ if (buflen == 0)
+ break;
+ buffer += tmp;
+ }
+ }
+
+ ret = qty;
+ }
+
+error:
+ return ret;
+}
+
+/*
+ * Allocate a keyring and link into the destination keyring.
+ */
+struct key *keyring_alloc(const char *description, uid_t uid, gid_t gid,
+ const struct cred *cred, unsigned long flags,
+ struct key *dest)
+{
+ struct key *keyring;
+ int ret;
+
+ keyring = key_alloc(&key_type_keyring, description,
+ uid, gid, cred,
+ (KEY_POS_ALL & ~KEY_POS_SETATTR) | KEY_USR_ALL,
+ flags);
+
+ if (!IS_ERR(keyring)) {
+ ret = key_instantiate_and_link(keyring, NULL, 0, dest, NULL);
+ if (ret < 0) {
+ key_put(keyring);
+ keyring = ERR_PTR(ret);
+ }
+ }
+
+ return keyring;
+}
+
+/**
+ * keyring_search_aux - Search a keyring tree for a key matching some criteria
+ * @keyring_ref: A pointer to the keyring with possession indicator.
+ * @cred: The credentials to use for permissions checks.
+ * @type: The type of key to search for.
+ * @description: Parameter for @match.
+ * @match: Function to rule on whether or not a key is the one required.
+ * @no_state_check: Don't check if a matching key is bad
+ *
+ * Search the supplied keyring tree for a key that matches the criteria given.
+ * The root keyring and any linked keyrings must grant Search permission to the
+ * caller to be searchable and keys can only be found if they too grant Search
+ * to the caller. The possession flag on the root keyring pointer controls use
+ * of the possessor bits in permissions checking of the entire tree. In
+ * addition, the LSM gets to forbid keyring searches and key matches.
+ *
+ * The search is performed as a breadth-then-depth search up to the prescribed
+ * limit (KEYRING_SEARCH_MAX_DEPTH).
+ *
+ * Keys are matched to the type provided and are then filtered by the match
+ * function, which is given the description to use in any way it sees fit. The
+ * match function may use any attributes of a key that it wishes to to
+ * determine the match. Normally the match function from the key type would be
+ * used.
+ *
+ * RCU is used to prevent the keyring key lists from disappearing without the
+ * need to take lots of locks.
+ *
+ * Returns a pointer to the found key and increments the key usage count if
+ * successful; -EAGAIN if no matching keys were found, or if expired or revoked
+ * keys were found; -ENOKEY if only negative keys were found; -ENOTDIR if the
+ * specified keyring wasn't a keyring.
+ *
+ * In the case of a successful return, the possession attribute from
+ * @keyring_ref is propagated to the returned key reference.
+ */
+key_ref_t keyring_search_aux(key_ref_t keyring_ref,
+ const struct cred *cred,
+ struct key_type *type,
+ const void *description,
+ key_match_func_t match,
+ bool no_state_check)
+{
+ struct {
+ struct keyring_list *keylist;
+ int kix;
+ } stack[KEYRING_SEARCH_MAX_DEPTH];
+
+ struct keyring_list *keylist;
+ struct timespec now;
+ unsigned long possessed, kflags;
+ struct key *keyring, *key;
+ key_ref_t key_ref;
+ long err;
+ int sp, kix;
+
+ keyring = key_ref_to_ptr(keyring_ref);
+ possessed = is_key_possessed(keyring_ref);
+ key_check(keyring);
+
+ /* top keyring must have search permission to begin the search */
+ err = key_task_permission(keyring_ref, cred, KEY_SEARCH);
+ if (err < 0) {
+ key_ref = ERR_PTR(err);
+ goto error;
+ }
+
+ key_ref = ERR_PTR(-ENOTDIR);
+ if (keyring->type != &key_type_keyring)
+ goto error;
+
+ rcu_read_lock();
+
+ now = current_kernel_time();
+ err = -EAGAIN;
+ sp = 0;
+
+ /* firstly we should check to see if this top-level keyring is what we
+ * are looking for */
+ key_ref = ERR_PTR(-EAGAIN);
+ kflags = keyring->flags;
+ if (keyring->type == type && match(keyring, description)) {
+ key = keyring;
+ if (no_state_check)
+ goto found;
+
+ /* check it isn't negative and hasn't expired or been
+ * revoked */
+ if (kflags & (1 << KEY_FLAG_REVOKED))
+ goto error_2;
+ if (key->expiry && now.tv_sec >= key->expiry)
+ goto error_2;
+ key_ref = ERR_PTR(key->type_data.reject_error);
+ if (kflags & (1 << KEY_FLAG_NEGATIVE))
+ goto error_2;
+ goto found;
+ }
+
+ /* otherwise, the top keyring must not be revoked, expired, or
+ * negatively instantiated if we are to search it */
+ key_ref = ERR_PTR(-EAGAIN);
+ if (kflags & ((1 << KEY_FLAG_REVOKED) | (1 << KEY_FLAG_NEGATIVE)) ||
+ (keyring->expiry && now.tv_sec >= keyring->expiry))
+ goto error_2;
+
+ /* start processing a new keyring */
+descend:
+ if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
+ goto not_this_keyring;
+
+ keylist = rcu_dereference(keyring->payload.subscriptions);
+ if (!keylist)
+ goto not_this_keyring;
+
+ /* iterate through the keys in this keyring first */
+ for (kix = 0; kix < keylist->nkeys; kix++) {
+ key = keylist->keys[kix];
+ kflags = key->flags;
+
+ /* ignore keys not of this type */
+ if (key->type != type)
+ continue;
+
+ /* skip revoked keys and expired keys */
+ if (!no_state_check) {
+ if (kflags & (1 << KEY_FLAG_REVOKED))
+ continue;
+
+ if (key->expiry && now.tv_sec >= key->expiry)
+ continue;
+ }
+
+ /* keys that don't match */
+ if (!match(key, description))
+ continue;
+
+ /* key must have search permissions */
+ if (key_task_permission(make_key_ref(key, possessed),
+ cred, KEY_SEARCH) < 0)
+ continue;
+
+ if (no_state_check)
+ goto found;
+
+ /* we set a different error code if we pass a negative key */
+ if (kflags & (1 << KEY_FLAG_NEGATIVE)) {
+ err = key->type_data.reject_error;
+ continue;
+ }
+
+ goto found;
+ }
+
+ /* search through the keyrings nested in this one */
+ kix = 0;
+ascend:
+ for (; kix < keylist->nkeys; kix++) {
+ key = keylist->keys[kix];
+ if (key->type != &key_type_keyring)
+ continue;
+
+ /* recursively search nested keyrings
+ * - only search keyrings for which we have search permission
+ */
+ if (sp >= KEYRING_SEARCH_MAX_DEPTH)
+ continue;
+
+ if (key_task_permission(make_key_ref(key, possessed),
+ cred, KEY_SEARCH) < 0)
+ continue;
+
+ /* stack the current position */
+ stack[sp].keylist = keylist;
+ stack[sp].kix = kix;
+ sp++;
+
+ /* begin again with the new keyring */
+ keyring = key;
+ goto descend;
+ }
+
+ /* the keyring we're looking at was disqualified or didn't contain a
+ * matching key */
+not_this_keyring:
+ if (sp > 0) {
+ /* resume the processing of a keyring higher up in the tree */
+ sp--;
+ keylist = stack[sp].keylist;
+ kix = stack[sp].kix + 1;
+ goto ascend;
+ }
+
+ key_ref = ERR_PTR(err);
+ goto error_2;
+
+ /* we found a viable match */
+found:
+ atomic_inc(&key->usage);
+ key_check(key);
+ key_ref = make_key_ref(key, possessed);
+error_2:
+ rcu_read_unlock();
+error:
+ return key_ref;
+}
+
+/**
+ * keyring_search - Search the supplied keyring tree for a matching key
+ * @keyring: The root of the keyring tree to be searched.
+ * @type: The type of keyring we want to find.
+ * @description: The name of the keyring we want to find.
+ *
+ * As keyring_search_aux() above, but using the current task's credentials and
+ * type's default matching function.
+ */
+key_ref_t keyring_search(key_ref_t keyring,
+ struct key_type *type,
+ const char *description)
+{
+ if (!type->match)
+ return ERR_PTR(-ENOKEY);
+
+ return keyring_search_aux(keyring, current->cred,
+ type, description, type->match, false);
+}
+EXPORT_SYMBOL(keyring_search);
+
+/*
+ * Search the given keyring only (no recursion).
+ *
+ * The caller must guarantee that the keyring is a keyring and that the
+ * permission is granted to search the keyring as no check is made here.
+ *
+ * RCU is used to make it unnecessary to lock the keyring key list here.
+ *
+ * Returns a pointer to the found key with usage count incremented if
+ * successful and returns -ENOKEY if not found. Revoked keys and keys not
+ * providing the requested permission are skipped over.
+ *
+ * If successful, the possession indicator is propagated from the keyring ref
+ * to the returned key reference.
+ */
+key_ref_t __keyring_search_one(key_ref_t keyring_ref,
+ const struct key_type *ktype,
+ const char *description,
+ key_perm_t perm)
+{
+ struct keyring_list *klist;
+ unsigned long possessed;
+ struct key *keyring, *key;
+ int loop;
+
+ keyring = key_ref_to_ptr(keyring_ref);
+ possessed = is_key_possessed(keyring_ref);
+
+ rcu_read_lock();
+
+ klist = rcu_dereference(keyring->payload.subscriptions);
+ if (klist) {
+ for (loop = 0; loop < klist->nkeys; loop++) {
+ key = klist->keys[loop];
+
+ if (key->type == ktype &&
+ (!key->type->match ||
+ key->type->match(key, description)) &&
+ key_permission(make_key_ref(key, possessed),
+ perm) == 0 &&
+ !test_bit(KEY_FLAG_REVOKED, &key->flags)
+ )
+ goto found;
+ }
+ }
+
+ rcu_read_unlock();
+ return ERR_PTR(-ENOKEY);
+
+found:
+ atomic_inc(&key->usage);
+ rcu_read_unlock();
+ return make_key_ref(key, possessed);
+}
+
+/*
+ * Find a keyring with the specified name.
+ *
+ * All named keyrings in the current user namespace are searched, provided they
+ * grant Search permission directly to the caller (unless this check is
+ * skipped). Keyrings whose usage points have reached zero or who have been
+ * revoked are skipped.
+ *
+ * Returns a pointer to the keyring with the keyring's refcount having being
+ * incremented on success. -ENOKEY is returned if a key could not be found.
+ */
+struct key *find_keyring_by_name(const char *name, bool skip_perm_check)
+{
+ struct key *keyring;
+ int bucket;
+
+ if (!name)
+ return ERR_PTR(-EINVAL);
+
+ bucket = keyring_hash(name);
+
+ read_lock(&keyring_name_lock);
+
+ if (keyring_name_hash[bucket].next) {
+ /* search this hash bucket for a keyring with a matching name
+ * that's readable and that hasn't been revoked */
+ list_for_each_entry(keyring,
+ &keyring_name_hash[bucket],
+ type_data.link
+ ) {
+ if (keyring->user->user_ns != current_user_ns())
+ continue;
+
+ if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
+ continue;
+
+ if (strcmp(keyring->description, name) != 0)
+ continue;
+
+ if (!skip_perm_check &&
+ key_permission(make_key_ref(keyring, 0),
+ KEY_SEARCH) < 0)
+ continue;
+
+ /* we've got a match but we might end up racing with
+ * key_cleanup() if the keyring is currently 'dead'
+ * (ie. it has a zero usage count) */
+ if (!atomic_inc_not_zero(&keyring->usage))
+ continue;
+ goto out;
+ }
+ }
+
+ keyring = ERR_PTR(-ENOKEY);
+out:
+ read_unlock(&keyring_name_lock);
+ return keyring;
+}
+
+/*
+ * See if a cycle will will be created by inserting acyclic tree B in acyclic
+ * tree A at the topmost level (ie: as a direct child of A).
+ *
+ * Since we are adding B to A at the top level, checking for cycles should just
+ * be a matter of seeing if node A is somewhere in tree B.
+ */
+static int keyring_detect_cycle(struct key *A, struct key *B)
+{
+ struct {
+ struct keyring_list *keylist;
+ int kix;
+ } stack[KEYRING_SEARCH_MAX_DEPTH];
+
+ struct keyring_list *keylist;
+ struct key *subtree, *key;
+ int sp, kix, ret;
+
+ rcu_read_lock();
+
+ ret = -EDEADLK;
+ if (A == B)
+ goto cycle_detected;
+
+ subtree = B;
+ sp = 0;
+
+ /* start processing a new keyring */
+descend:
+ if (test_bit(KEY_FLAG_REVOKED, &subtree->flags))
+ goto not_this_keyring;
+
+ keylist = rcu_dereference(subtree->payload.subscriptions);
+ if (!keylist)
+ goto not_this_keyring;
+ kix = 0;
+
+ascend:
+ /* iterate through the remaining keys in this keyring */
+ for (; kix < keylist->nkeys; kix++) {
+ key = keylist->keys[kix];
+
+ if (key == A)
+ goto cycle_detected;
+
+ /* recursively check nested keyrings */
+ if (key->type == &key_type_keyring) {
+ if (sp >= KEYRING_SEARCH_MAX_DEPTH)
+ goto too_deep;
+
+ /* stack the current position */
+ stack[sp].keylist = keylist;
+ stack[sp].kix = kix;
+ sp++;
+
+ /* begin again with the new keyring */
+ subtree = key;
+ goto descend;
+ }
+ }
+
+ /* the keyring we're looking at was disqualified or didn't contain a
+ * matching key */
+not_this_keyring:
+ if (sp > 0) {
+ /* resume the checking of a keyring higher up in the tree */
+ sp--;
+ keylist = stack[sp].keylist;
+ kix = stack[sp].kix + 1;
+ goto ascend;
+ }
+
+ ret = 0; /* no cycles detected */
+
+error:
+ rcu_read_unlock();
+ return ret;
+
+too_deep:
+ ret = -ELOOP;
+ goto error;
+
+cycle_detected:
+ ret = -EDEADLK;
+ goto error;
+}
+
+/*
+ * Dispose of a keyring list after the RCU grace period, freeing the unlinked
+ * key
+ */
+static void keyring_unlink_rcu_disposal(struct rcu_head *rcu)
+{
+ struct keyring_list *klist =
+ container_of(rcu, struct keyring_list, rcu);
+
+ if (klist->delkey != USHRT_MAX)
+ key_put(klist->keys[klist->delkey]);
+ kfree(klist);
+}
+
+/*
+ * Preallocate memory so that a key can be linked into to a keyring.
+ */
+int __key_link_begin(struct key *keyring, const struct key_type *type,
+ const char *description, unsigned long *_prealloc)
+ __acquires(&keyring->sem)
+{
+ struct keyring_list *klist, *nklist;
+ unsigned long prealloc;
+ unsigned max;
+ size_t size;
+ int loop, ret;
+
+ kenter("%d,%s,%s,", key_serial(keyring), type->name, description);
+
+ if (keyring->type != &key_type_keyring)
+ return -ENOTDIR;
+
+ down_write(&keyring->sem);
+
+ ret = -EKEYREVOKED;
+ if (test_bit(KEY_FLAG_REVOKED, &keyring->flags))
+ goto error_krsem;
+
+ /* serialise link/link calls to prevent parallel calls causing a cycle
+ * when linking two keyring in opposite orders */
+ if (type == &key_type_keyring)
+ down_write(&keyring_serialise_link_sem);
+
+ klist = rcu_dereference_locked_keyring(keyring);
+
+ /* see if there's a matching key we can displace */
+ if (klist && klist->nkeys > 0) {
+ for (loop = klist->nkeys - 1; loop >= 0; loop--) {
+ if (klist->keys[loop]->type == type &&
+ strcmp(klist->keys[loop]->description,
+ description) == 0
+ ) {
+ /* found a match - we'll replace this one with
+ * the new key */
+ size = sizeof(struct key *) * klist->maxkeys;
+ size += sizeof(*klist);
+ BUG_ON(size > PAGE_SIZE);
+
+ ret = -ENOMEM;
+ nklist = kmemdup(klist, size, GFP_KERNEL);
+ if (!nklist)
+ goto error_sem;
+
+ /* note replacement slot */
+ klist->delkey = nklist->delkey = loop;
+ prealloc = (unsigned long)nklist;
+ goto done;
+ }
+ }
+ }
+
+ /* check that we aren't going to overrun the user's quota */
+ ret = key_payload_reserve(keyring,
+ keyring->datalen + KEYQUOTA_LINK_BYTES);
+ if (ret < 0)
+ goto error_sem;
+
+ if (klist && klist->nkeys < klist->maxkeys) {
+ /* there's sufficient slack space to append directly */
+ nklist = NULL;
+ prealloc = KEY_LINK_FIXQUOTA;
+ } else {
+ /* grow the key list */
+ max = 4;
+ if (klist)
+ max += klist->maxkeys;
+
+ ret = -ENFILE;
+ if (max > USHRT_MAX - 1)
+ goto error_quota;
+ size = sizeof(*klist) + sizeof(struct key *) * max;
+ if (size > PAGE_SIZE)
+ goto error_quota;
+
+ ret = -ENOMEM;
+ nklist = kmalloc(size, GFP_KERNEL);
+ if (!nklist)
+ goto error_quota;
+
+ nklist->maxkeys = max;
+ if (klist) {
+ memcpy(nklist->keys, klist->keys,
+ sizeof(struct key *) * klist->nkeys);
+ nklist->delkey = klist->nkeys;
+ nklist->nkeys = klist->nkeys + 1;
+ klist->delkey = USHRT_MAX;
+ } else {
+ nklist->nkeys = 1;
+ nklist->delkey = 0;
+ }
+
+ /* add the key into the new space */
+ nklist->keys[nklist->delkey] = NULL;
+ }
+
+ prealloc = (unsigned long)nklist | KEY_LINK_FIXQUOTA;
+done:
+ *_prealloc = prealloc;
+ kleave(" = 0");
+ return 0;
+
+error_quota:
+ /* undo the quota changes */
+ key_payload_reserve(keyring,
+ keyring->datalen - KEYQUOTA_LINK_BYTES);
+error_sem:
+ if (type == &key_type_keyring)
+ up_write(&keyring_serialise_link_sem);
+error_krsem:
+ up_write(&keyring->sem);
+ kleave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * Check already instantiated keys aren't going to be a problem.
+ *
+ * The caller must have called __key_link_begin(). Don't need to call this for
+ * keys that were created since __key_link_begin() was called.
+ */
+int __key_link_check_live_key(struct key *keyring, struct key *key)
+{
+ if (key->type == &key_type_keyring)
+ /* check that we aren't going to create a cycle by linking one
+ * keyring to another */
+ return keyring_detect_cycle(keyring, key);
+ return 0;
+}
+
+/*
+ * Link a key into to a keyring.
+ *
+ * Must be called with __key_link_begin() having being called. Discards any
+ * already extant link to matching key if there is one, so that each keyring
+ * holds at most one link to any given key of a particular type+description
+ * combination.
+ */
+void __key_link(struct key *keyring, struct key *key,
+ unsigned long *_prealloc)
+{
+ struct keyring_list *klist, *nklist;
+
+ nklist = (struct keyring_list *)(*_prealloc & ~KEY_LINK_FIXQUOTA);
+ *_prealloc = 0;
+
+ kenter("%d,%d,%p", keyring->serial, key->serial, nklist);
+
+ klist = rcu_dereference_protected(keyring->payload.subscriptions,
+ rwsem_is_locked(&keyring->sem));
+
+ atomic_inc(&key->usage);
+
+ /* there's a matching key we can displace or an empty slot in a newly
+ * allocated list we can fill */
+ if (nklist) {
+ kdebug("replace %hu/%hu/%hu",
+ nklist->delkey, nklist->nkeys, nklist->maxkeys);
+
+ nklist->keys[nklist->delkey] = key;
+
+ rcu_assign_pointer(keyring->payload.subscriptions, nklist);
+
+ /* dispose of the old keyring list and, if there was one, the
+ * displaced key */
+ if (klist) {
+ kdebug("dispose %hu/%hu/%hu",
+ klist->delkey, klist->nkeys, klist->maxkeys);
+ call_rcu(&klist->rcu, keyring_unlink_rcu_disposal);
+ }
+ } else {
+ /* there's sufficient slack space to append directly */
+ klist->keys[klist->nkeys] = key;
+ smp_wmb();
+ klist->nkeys++;
+ }
+}
+
+/*
+ * Finish linking a key into to a keyring.
+ *
+ * Must be called with __key_link_begin() having being called.
+ */
+void __key_link_end(struct key *keyring, struct key_type *type,
+ unsigned long prealloc)
+ __releases(&keyring->sem)
+{
+ BUG_ON(type == NULL);
+ BUG_ON(type->name == NULL);
+ kenter("%d,%s,%lx", keyring->serial, type->name, prealloc);
+
+ if (type == &key_type_keyring)
+ up_write(&keyring_serialise_link_sem);
+
+ if (prealloc) {
+ if (prealloc & KEY_LINK_FIXQUOTA)
+ key_payload_reserve(keyring,
+ keyring->datalen -
+ KEYQUOTA_LINK_BYTES);
+ kfree((struct keyring_list *)(prealloc & ~KEY_LINK_FIXQUOTA));
+ }
+ up_write(&keyring->sem);
+}
+
+/**
+ * key_link - Link a key to a keyring
+ * @keyring: The keyring to make the link in.
+ * @key: The key to link to.
+ *
+ * Make a link in a keyring to a key, such that the keyring holds a reference
+ * on that key and the key can potentially be found by searching that keyring.
+ *
+ * This function will write-lock the keyring's semaphore and will consume some
+ * of the user's key data quota to hold the link.
+ *
+ * Returns 0 if successful, -ENOTDIR if the keyring isn't a keyring,
+ * -EKEYREVOKED if the keyring has been revoked, -ENFILE if the keyring is
+ * full, -EDQUOT if there is insufficient key data quota remaining to add
+ * another link or -ENOMEM if there's insufficient memory.
+ *
+ * It is assumed that the caller has checked that it is permitted for a link to
+ * be made (the keyring should have Write permission and the key Link
+ * permission).
+ */
+int key_link(struct key *keyring, struct key *key)
+{
+ unsigned long prealloc;
+ int ret;
+
+ key_check(keyring);
+ key_check(key);
+
+ ret = __key_link_begin(keyring, key->type, key->description, &prealloc);
+ if (ret == 0) {
+ ret = __key_link_check_live_key(keyring, key);
+ if (ret == 0)
+ __key_link(keyring, key, &prealloc);
+ __key_link_end(keyring, key->type, prealloc);
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(key_link);
+
+/**
+ * key_unlink - Unlink the first link to a key from a keyring.
+ * @keyring: The keyring to remove the link from.
+ * @key: The key the link is to.
+ *
+ * Remove a link from a keyring to a key.
+ *
+ * This function will write-lock the keyring's semaphore.
+ *
+ * Returns 0 if successful, -ENOTDIR if the keyring isn't a keyring, -ENOENT if
+ * the key isn't linked to by the keyring or -ENOMEM if there's insufficient
+ * memory.
+ *
+ * It is assumed that the caller has checked that it is permitted for a link to
+ * be removed (the keyring should have Write permission; no permissions are
+ * required on the key).
+ */
+int key_unlink(struct key *keyring, struct key *key)
+{
+ struct keyring_list *klist, *nklist;
+ int loop, ret;
+
+ key_check(keyring);
+ key_check(key);
+
+ ret = -ENOTDIR;
+ if (keyring->type != &key_type_keyring)
+ goto error;
+
+ down_write(&keyring->sem);
+
+ klist = rcu_dereference_locked_keyring(keyring);
+ if (klist) {
+ /* search the keyring for the key */
+ for (loop = 0; loop < klist->nkeys; loop++)
+ if (klist->keys[loop] == key)
+ goto key_is_present;
+ }
+
+ up_write(&keyring->sem);
+ ret = -ENOENT;
+ goto error;
+
+key_is_present:
+ /* we need to copy the key list for RCU purposes */
+ nklist = kmalloc(sizeof(*klist) +
+ sizeof(struct key *) * klist->maxkeys,
+ GFP_KERNEL);
+ if (!nklist)
+ goto nomem;
+ nklist->maxkeys = klist->maxkeys;
+ nklist->nkeys = klist->nkeys - 1;
+
+ if (loop > 0)
+ memcpy(&nklist->keys[0],
+ &klist->keys[0],
+ loop * sizeof(struct key *));
+
+ if (loop < nklist->nkeys)
+ memcpy(&nklist->keys[loop],
+ &klist->keys[loop + 1],
+ (nklist->nkeys - loop) * sizeof(struct key *));
+
+ /* adjust the user's quota */
+ key_payload_reserve(keyring,
+ keyring->datalen - KEYQUOTA_LINK_BYTES);
+
+ rcu_assign_pointer(keyring->payload.subscriptions, nklist);
+
+ up_write(&keyring->sem);
+
+ /* schedule for later cleanup */
+ klist->delkey = loop;
+ call_rcu(&klist->rcu, keyring_unlink_rcu_disposal);
+
+ ret = 0;
+
+error:
+ return ret;
+nomem:
+ ret = -ENOMEM;
+ up_write(&keyring->sem);
+ goto error;
+}
+EXPORT_SYMBOL(key_unlink);
+
+/*
+ * Dispose of a keyring list after the RCU grace period, releasing the keys it
+ * links to.
+ */
+static void keyring_clear_rcu_disposal(struct rcu_head *rcu)
+{
+ struct keyring_list *klist;
+ int loop;
+
+ klist = container_of(rcu, struct keyring_list, rcu);
+
+ for (loop = klist->nkeys - 1; loop >= 0; loop--)
+ key_put(klist->keys[loop]);
+
+ kfree(klist);
+}
+
+/**
+ * keyring_clear - Clear a keyring
+ * @keyring: The keyring to clear.
+ *
+ * Clear the contents of the specified keyring.
+ *
+ * Returns 0 if successful or -ENOTDIR if the keyring isn't a keyring.
+ */
+int keyring_clear(struct key *keyring)
+{
+ struct keyring_list *klist;
+ int ret;
+
+ ret = -ENOTDIR;
+ if (keyring->type == &key_type_keyring) {
+ /* detach the pointer block with the locks held */
+ down_write(&keyring->sem);
+
+ klist = rcu_dereference_locked_keyring(keyring);
+ if (klist) {
+ /* adjust the quota */
+ key_payload_reserve(keyring,
+ sizeof(struct keyring_list));
+
+ rcu_assign_pointer(keyring->payload.subscriptions,
+ NULL);
+ }
+
+ up_write(&keyring->sem);
+
+ /* free the keys after the locks have been dropped */
+ if (klist)
+ call_rcu(&klist->rcu, keyring_clear_rcu_disposal);
+
+ ret = 0;
+ }
+
+ return ret;
+}
+EXPORT_SYMBOL(keyring_clear);
+
+/*
+ * Dispose of the links from a revoked keyring.
+ *
+ * This is called with the key sem write-locked.
+ */
+static void keyring_revoke(struct key *keyring)
+{
+ struct keyring_list *klist;
+
+ klist = rcu_dereference_locked_keyring(keyring);
+
+ /* adjust the quota */
+ key_payload_reserve(keyring, 0);
+
+ if (klist) {
+ rcu_assign_pointer(keyring->payload.subscriptions, NULL);
+ call_rcu(&klist->rcu, keyring_clear_rcu_disposal);
+ }
+}
+
+/*
+ * Determine whether a key is dead.
+ */
+static bool key_is_dead(struct key *key, time_t limit)
+{
+ return test_bit(KEY_FLAG_DEAD, &key->flags) ||
+ (key->expiry > 0 && key->expiry <= limit);
+}
+
+/*
+ * Collect garbage from the contents of a keyring, replacing the old list with
+ * a new one with the pointers all shuffled down.
+ *
+ * Dead keys are classed as oned that are flagged as being dead or are revoked,
+ * expired or negative keys that were revoked or expired before the specified
+ * limit.
+ */
+void keyring_gc(struct key *keyring, time_t limit)
+{
+ struct keyring_list *klist, *new;
+ struct key *key;
+ int loop, keep, max;
+
+ kenter("{%x,%s}", key_serial(keyring), keyring->description);
+
+ down_write(&keyring->sem);
+
+ klist = rcu_dereference_locked_keyring(keyring);
+ if (!klist)
+ goto no_klist;
+
+ /* work out how many subscriptions we're keeping */
+ keep = 0;
+ for (loop = klist->nkeys - 1; loop >= 0; loop--)
+ if (!key_is_dead(klist->keys[loop], limit))
+ keep++;
+
+ if (keep == klist->nkeys)
+ goto just_return;
+
+ /* allocate a new keyring payload */
+ max = roundup(keep, 4);
+ new = kmalloc(sizeof(struct keyring_list) + max * sizeof(struct key *),
+ GFP_KERNEL);
+ if (!new)
+ goto nomem;
+ new->maxkeys = max;
+ new->nkeys = 0;
+ new->delkey = 0;
+
+ /* install the live keys
+ * - must take care as expired keys may be updated back to life
+ */
+ keep = 0;
+ for (loop = klist->nkeys - 1; loop >= 0; loop--) {
+ key = klist->keys[loop];
+ if (!key_is_dead(key, limit)) {
+ if (keep >= max)
+ goto discard_new;
+ new->keys[keep++] = key_get(key);
+ }
+ }
+ new->nkeys = keep;
+
+ /* adjust the quota */
+ key_payload_reserve(keyring,
+ sizeof(struct keyring_list) +
+ KEYQUOTA_LINK_BYTES * keep);
+
+ if (keep == 0) {
+ rcu_assign_pointer(keyring->payload.subscriptions, NULL);
+ kfree(new);
+ } else {
+ rcu_assign_pointer(keyring->payload.subscriptions, new);
+ }
+
+ up_write(&keyring->sem);
+
+ call_rcu(&klist->rcu, keyring_clear_rcu_disposal);
+ kleave(" [yes]");
+ return;
+
+discard_new:
+ new->nkeys = keep;
+ keyring_clear_rcu_disposal(&new->rcu);
+ up_write(&keyring->sem);
+ kleave(" [discard]");
+ return;
+
+just_return:
+ up_write(&keyring->sem);
+ kleave(" [no dead]");
+ return;
+
+no_klist:
+ up_write(&keyring->sem);
+ kleave(" [no_klist]");
+ return;
+
+nomem:
+ up_write(&keyring->sem);
+ kleave(" [oom]");
+}
diff --git a/security/keys/permission.c b/security/keys/permission.c
new file mode 100644
index 00000000..c35b5229
--- /dev/null
+++ b/security/keys/permission.c
@@ -0,0 +1,118 @@
+/* Key permission checking
+ *
+ * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/security.h>
+#include "internal.h"
+
+/**
+ * key_task_permission - Check a key can be used
+ * @key_ref: The key to check.
+ * @cred: The credentials to use.
+ * @perm: The permissions to check for.
+ *
+ * Check to see whether permission is granted to use a key in the desired way,
+ * but permit the security modules to override.
+ *
+ * The caller must hold either a ref on cred or must hold the RCU readlock.
+ *
+ * Returns 0 if successful, -EACCES if access is denied based on the
+ * permissions bits or the LSM check.
+ */
+int key_task_permission(const key_ref_t key_ref, const struct cred *cred,
+ key_perm_t perm)
+{
+ struct key *key;
+ key_perm_t kperm;
+ int ret;
+
+ key = key_ref_to_ptr(key_ref);
+
+ if (key->user->user_ns != cred->user->user_ns)
+ goto use_other_perms;
+
+ /* use the second 8-bits of permissions for keys the caller owns */
+ if (key->uid == cred->fsuid) {
+ kperm = key->perm >> 16;
+ goto use_these_perms;
+ }
+
+ /* use the third 8-bits of permissions for keys the caller has a group
+ * membership in common with */
+ if (key->gid != -1 && key->perm & KEY_GRP_ALL) {
+ if (key->gid == cred->fsgid) {
+ kperm = key->perm >> 8;
+ goto use_these_perms;
+ }
+
+ ret = groups_search(cred->group_info, key->gid);
+ if (ret) {
+ kperm = key->perm >> 8;
+ goto use_these_perms;
+ }
+ }
+
+use_other_perms:
+
+ /* otherwise use the least-significant 8-bits */
+ kperm = key->perm;
+
+use_these_perms:
+
+ /* use the top 8-bits of permissions for keys the caller possesses
+ * - possessor permissions are additive with other permissions
+ */
+ if (is_key_possessed(key_ref))
+ kperm |= key->perm >> 24;
+
+ kperm = kperm & perm & KEY_ALL;
+
+ if (kperm != perm)
+ return -EACCES;
+
+ /* let LSM be the final arbiter */
+ return security_key_permission(key_ref, cred, perm);
+}
+EXPORT_SYMBOL(key_task_permission);
+
+/**
+ * key_validate - Validate a key.
+ * @key: The key to be validated.
+ *
+ * Check that a key is valid, returning 0 if the key is okay, -EKEYREVOKED if
+ * the key's type has been removed or if the key has been revoked or
+ * -EKEYEXPIRED if the key has expired.
+ */
+int key_validate(struct key *key)
+{
+ struct timespec now;
+ int ret = 0;
+
+ if (key) {
+ /* check it's still accessible */
+ ret = -EKEYREVOKED;
+ if (test_bit(KEY_FLAG_REVOKED, &key->flags) ||
+ test_bit(KEY_FLAG_DEAD, &key->flags))
+ goto error;
+
+ /* check it hasn't expired */
+ ret = 0;
+ if (key->expiry) {
+ now = current_kernel_time();
+ if (now.tv_sec >= key->expiry)
+ ret = -EKEYEXPIRED;
+ }
+ }
+
+error:
+ return ret;
+}
+EXPORT_SYMBOL(key_validate);
diff --git a/security/keys/proc.c b/security/keys/proc.c
new file mode 100644
index 00000000..49bbc979
--- /dev/null
+++ b/security/keys/proc.c
@@ -0,0 +1,352 @@
+/* procfs files for key database enumeration
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/fs.h>
+#include <linux/proc_fs.h>
+#include <linux/seq_file.h>
+#include <asm/errno.h>
+#include "internal.h"
+
+#ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
+static int proc_keys_open(struct inode *inode, struct file *file);
+static void *proc_keys_start(struct seq_file *p, loff_t *_pos);
+static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos);
+static void proc_keys_stop(struct seq_file *p, void *v);
+static int proc_keys_show(struct seq_file *m, void *v);
+
+static const struct seq_operations proc_keys_ops = {
+ .start = proc_keys_start,
+ .next = proc_keys_next,
+ .stop = proc_keys_stop,
+ .show = proc_keys_show,
+};
+
+static const struct file_operations proc_keys_fops = {
+ .open = proc_keys_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+#endif
+
+static int proc_key_users_open(struct inode *inode, struct file *file);
+static void *proc_key_users_start(struct seq_file *p, loff_t *_pos);
+static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos);
+static void proc_key_users_stop(struct seq_file *p, void *v);
+static int proc_key_users_show(struct seq_file *m, void *v);
+
+static const struct seq_operations proc_key_users_ops = {
+ .start = proc_key_users_start,
+ .next = proc_key_users_next,
+ .stop = proc_key_users_stop,
+ .show = proc_key_users_show,
+};
+
+static const struct file_operations proc_key_users_fops = {
+ .open = proc_key_users_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+/*
+ * Declare the /proc files.
+ */
+static int __init key_proc_init(void)
+{
+ struct proc_dir_entry *p;
+
+#ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
+ p = proc_create("keys", 0, NULL, &proc_keys_fops);
+ if (!p)
+ panic("Cannot create /proc/keys\n");
+#endif
+
+ p = proc_create("key-users", 0, NULL, &proc_key_users_fops);
+ if (!p)
+ panic("Cannot create /proc/key-users\n");
+
+ return 0;
+}
+
+__initcall(key_proc_init);
+
+/*
+ * Implement "/proc/keys" to provide a list of the keys on the system that
+ * grant View permission to the caller.
+ */
+#ifdef CONFIG_KEYS_DEBUG_PROC_KEYS
+
+static struct rb_node *key_serial_next(struct rb_node *n)
+{
+ struct user_namespace *user_ns = current_user_ns();
+
+ n = rb_next(n);
+ while (n) {
+ struct key *key = rb_entry(n, struct key, serial_node);
+ if (key->user->user_ns == user_ns)
+ break;
+ n = rb_next(n);
+ }
+ return n;
+}
+
+static int proc_keys_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &proc_keys_ops);
+}
+
+static struct key *find_ge_key(key_serial_t id)
+{
+ struct user_namespace *user_ns = current_user_ns();
+ struct rb_node *n = key_serial_tree.rb_node;
+ struct key *minkey = NULL;
+
+ while (n) {
+ struct key *key = rb_entry(n, struct key, serial_node);
+ if (id < key->serial) {
+ if (!minkey || minkey->serial > key->serial)
+ minkey = key;
+ n = n->rb_left;
+ } else if (id > key->serial) {
+ n = n->rb_right;
+ } else {
+ minkey = key;
+ break;
+ }
+ key = NULL;
+ }
+
+ if (!minkey)
+ return NULL;
+
+ for (;;) {
+ if (minkey->user->user_ns == user_ns)
+ return minkey;
+ n = rb_next(&minkey->serial_node);
+ if (!n)
+ return NULL;
+ minkey = rb_entry(n, struct key, serial_node);
+ }
+}
+
+static void *proc_keys_start(struct seq_file *p, loff_t *_pos)
+ __acquires(key_serial_lock)
+{
+ key_serial_t pos = *_pos;
+ struct key *key;
+
+ spin_lock(&key_serial_lock);
+
+ if (*_pos > INT_MAX)
+ return NULL;
+ key = find_ge_key(pos);
+ if (!key)
+ return NULL;
+ *_pos = key->serial;
+ return &key->serial_node;
+}
+
+static inline key_serial_t key_node_serial(struct rb_node *n)
+{
+ struct key *key = rb_entry(n, struct key, serial_node);
+ return key->serial;
+}
+
+static void *proc_keys_next(struct seq_file *p, void *v, loff_t *_pos)
+{
+ struct rb_node *n;
+
+ n = key_serial_next(v);
+ if (n)
+ *_pos = key_node_serial(n);
+ return n;
+}
+
+static void proc_keys_stop(struct seq_file *p, void *v)
+ __releases(key_serial_lock)
+{
+ spin_unlock(&key_serial_lock);
+}
+
+static int proc_keys_show(struct seq_file *m, void *v)
+{
+ const struct cred *cred = current_cred();
+ struct rb_node *_p = v;
+ struct key *key = rb_entry(_p, struct key, serial_node);
+ struct timespec now;
+ unsigned long timo;
+ key_ref_t key_ref, skey_ref;
+ char xbuf[12];
+ int rc;
+
+ key_ref = make_key_ref(key, 0);
+
+ /* determine if the key is possessed by this process (a test we can
+ * skip if the key does not indicate the possessor can view it
+ */
+ if (key->perm & KEY_POS_VIEW) {
+ skey_ref = search_my_process_keyrings(key->type, key,
+ lookup_user_key_possessed,
+ true, cred);
+ if (!IS_ERR(skey_ref)) {
+ key_ref_put(skey_ref);
+ key_ref = make_key_ref(key, 1);
+ }
+ }
+
+ /* check whether the current task is allowed to view the key (assuming
+ * non-possession)
+ * - the caller holds a spinlock, and thus the RCU read lock, making our
+ * access to __current_cred() safe
+ */
+ rc = key_task_permission(key_ref, cred, KEY_VIEW);
+ if (rc < 0)
+ return 0;
+
+ now = current_kernel_time();
+
+ rcu_read_lock();
+
+ /* come up with a suitable timeout value */
+ if (key->expiry == 0) {
+ memcpy(xbuf, "perm", 5);
+ } else if (now.tv_sec >= key->expiry) {
+ memcpy(xbuf, "expd", 5);
+ } else {
+ timo = key->expiry - now.tv_sec;
+
+ if (timo < 60)
+ sprintf(xbuf, "%lus", timo);
+ else if (timo < 60*60)
+ sprintf(xbuf, "%lum", timo / 60);
+ else if (timo < 60*60*24)
+ sprintf(xbuf, "%luh", timo / (60*60));
+ else if (timo < 60*60*24*7)
+ sprintf(xbuf, "%lud", timo / (60*60*24));
+ else
+ sprintf(xbuf, "%luw", timo / (60*60*24*7));
+ }
+
+#define showflag(KEY, LETTER, FLAG) \
+ (test_bit(FLAG, &(KEY)->flags) ? LETTER : '-')
+
+ seq_printf(m, "%08x %c%c%c%c%c%c %5d %4s %08x %5d %5d %-9.9s ",
+ key->serial,
+ showflag(key, 'I', KEY_FLAG_INSTANTIATED),
+ showflag(key, 'R', KEY_FLAG_REVOKED),
+ showflag(key, 'D', KEY_FLAG_DEAD),
+ showflag(key, 'Q', KEY_FLAG_IN_QUOTA),
+ showflag(key, 'U', KEY_FLAG_USER_CONSTRUCT),
+ showflag(key, 'N', KEY_FLAG_NEGATIVE),
+ atomic_read(&key->usage),
+ xbuf,
+ key->perm,
+ key->uid,
+ key->gid,
+ key->type->name);
+
+#undef showflag
+
+ if (key->type->describe)
+ key->type->describe(key, m);
+ seq_putc(m, '\n');
+
+ rcu_read_unlock();
+ return 0;
+}
+
+#endif /* CONFIG_KEYS_DEBUG_PROC_KEYS */
+
+static struct rb_node *__key_user_next(struct rb_node *n)
+{
+ while (n) {
+ struct key_user *user = rb_entry(n, struct key_user, node);
+ if (user->user_ns == current_user_ns())
+ break;
+ n = rb_next(n);
+ }
+ return n;
+}
+
+static struct rb_node *key_user_next(struct rb_node *n)
+{
+ return __key_user_next(rb_next(n));
+}
+
+static struct rb_node *key_user_first(struct rb_root *r)
+{
+ struct rb_node *n = rb_first(r);
+ return __key_user_next(n);
+}
+
+/*
+ * Implement "/proc/key-users" to provides a list of the key users and their
+ * quotas.
+ */
+static int proc_key_users_open(struct inode *inode, struct file *file)
+{
+ return seq_open(file, &proc_key_users_ops);
+}
+
+static void *proc_key_users_start(struct seq_file *p, loff_t *_pos)
+ __acquires(key_user_lock)
+{
+ struct rb_node *_p;
+ loff_t pos = *_pos;
+
+ spin_lock(&key_user_lock);
+
+ _p = key_user_first(&key_user_tree);
+ while (pos > 0 && _p) {
+ pos--;
+ _p = key_user_next(_p);
+ }
+
+ return _p;
+}
+
+static void *proc_key_users_next(struct seq_file *p, void *v, loff_t *_pos)
+{
+ (*_pos)++;
+ return key_user_next((struct rb_node *)v);
+}
+
+static void proc_key_users_stop(struct seq_file *p, void *v)
+ __releases(key_user_lock)
+{
+ spin_unlock(&key_user_lock);
+}
+
+static int proc_key_users_show(struct seq_file *m, void *v)
+{
+ struct rb_node *_p = v;
+ struct key_user *user = rb_entry(_p, struct key_user, node);
+ unsigned maxkeys = (user->uid == 0) ?
+ key_quota_root_maxkeys : key_quota_maxkeys;
+ unsigned maxbytes = (user->uid == 0) ?
+ key_quota_root_maxbytes : key_quota_maxbytes;
+
+ seq_printf(m, "%5u: %5d %d/%d %d/%d %d/%d\n",
+ user->uid,
+ atomic_read(&user->usage),
+ atomic_read(&user->nkeys),
+ atomic_read(&user->nikeys),
+ user->qnkeys,
+ maxkeys,
+ user->qnbytes,
+ maxbytes);
+
+ return 0;
+}
diff --git a/security/keys/process_keys.c b/security/keys/process_keys.c
new file mode 100644
index 00000000..a3063eb3
--- /dev/null
+++ b/security/keys/process_keys.c
@@ -0,0 +1,867 @@
+/* Manage a process's keyrings
+ *
+ * Copyright (C) 2004-2005, 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/sched.h>
+#include <linux/keyctl.h>
+#include <linux/fs.h>
+#include <linux/err.h>
+#include <linux/mutex.h>
+#include <linux/security.h>
+#include <linux/user_namespace.h>
+#include <asm/uaccess.h>
+#include "internal.h"
+
+/* Session keyring create vs join semaphore */
+static DEFINE_MUTEX(key_session_mutex);
+
+/* User keyring creation semaphore */
+static DEFINE_MUTEX(key_user_keyring_mutex);
+
+/* The root user's tracking struct */
+struct key_user root_key_user = {
+ .usage = ATOMIC_INIT(3),
+ .cons_lock = __MUTEX_INITIALIZER(root_key_user.cons_lock),
+ .lock = __SPIN_LOCK_UNLOCKED(root_key_user.lock),
+ .nkeys = ATOMIC_INIT(2),
+ .nikeys = ATOMIC_INIT(2),
+ .uid = 0,
+ .user_ns = &init_user_ns,
+};
+
+/*
+ * Install the user and user session keyrings for the current process's UID.
+ */
+int install_user_keyrings(void)
+{
+ struct user_struct *user;
+ const struct cred *cred;
+ struct key *uid_keyring, *session_keyring;
+ char buf[20];
+ int ret;
+
+ cred = current_cred();
+ user = cred->user;
+
+ kenter("%p{%u}", user, user->uid);
+
+ if (user->uid_keyring) {
+ kleave(" = 0 [exist]");
+ return 0;
+ }
+
+ mutex_lock(&key_user_keyring_mutex);
+ ret = 0;
+
+ if (!user->uid_keyring) {
+ /* get the UID-specific keyring
+ * - there may be one in existence already as it may have been
+ * pinned by a session, but the user_struct pointing to it
+ * may have been destroyed by setuid */
+ sprintf(buf, "_uid.%u", user->uid);
+
+ uid_keyring = find_keyring_by_name(buf, true);
+ if (IS_ERR(uid_keyring)) {
+ uid_keyring = keyring_alloc(buf, user->uid, (gid_t) -1,
+ cred, KEY_ALLOC_IN_QUOTA,
+ NULL);
+ if (IS_ERR(uid_keyring)) {
+ ret = PTR_ERR(uid_keyring);
+ goto error;
+ }
+ }
+
+ /* get a default session keyring (which might also exist
+ * already) */
+ sprintf(buf, "_uid_ses.%u", user->uid);
+
+ session_keyring = find_keyring_by_name(buf, true);
+ if (IS_ERR(session_keyring)) {
+ session_keyring =
+ keyring_alloc(buf, user->uid, (gid_t) -1,
+ cred, KEY_ALLOC_IN_QUOTA, NULL);
+ if (IS_ERR(session_keyring)) {
+ ret = PTR_ERR(session_keyring);
+ goto error_release;
+ }
+
+ /* we install a link from the user session keyring to
+ * the user keyring */
+ ret = key_link(session_keyring, uid_keyring);
+ if (ret < 0)
+ goto error_release_both;
+ }
+
+ /* install the keyrings */
+ user->uid_keyring = uid_keyring;
+ user->session_keyring = session_keyring;
+ }
+
+ mutex_unlock(&key_user_keyring_mutex);
+ kleave(" = 0");
+ return 0;
+
+error_release_both:
+ key_put(session_keyring);
+error_release:
+ key_put(uid_keyring);
+error:
+ mutex_unlock(&key_user_keyring_mutex);
+ kleave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * Install a fresh thread keyring directly to new credentials. This keyring is
+ * allowed to overrun the quota.
+ */
+int install_thread_keyring_to_cred(struct cred *new)
+{
+ struct key *keyring;
+
+ keyring = keyring_alloc("_tid", new->uid, new->gid, new,
+ KEY_ALLOC_QUOTA_OVERRUN, NULL);
+ if (IS_ERR(keyring))
+ return PTR_ERR(keyring);
+
+ new->thread_keyring = keyring;
+ return 0;
+}
+
+/*
+ * Install a fresh thread keyring, discarding the old one.
+ */
+static int install_thread_keyring(void)
+{
+ struct cred *new;
+ int ret;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ BUG_ON(new->thread_keyring);
+
+ ret = install_thread_keyring_to_cred(new);
+ if (ret < 0) {
+ abort_creds(new);
+ return ret;
+ }
+
+ return commit_creds(new);
+}
+
+/*
+ * Install a process keyring directly to a credentials struct.
+ *
+ * Returns -EEXIST if there was already a process keyring, 0 if one installed,
+ * and other value on any other error
+ */
+int install_process_keyring_to_cred(struct cred *new)
+{
+ struct key *keyring;
+ int ret;
+
+ if (new->tgcred->process_keyring)
+ return -EEXIST;
+
+ keyring = keyring_alloc("_pid", new->uid, new->gid,
+ new, KEY_ALLOC_QUOTA_OVERRUN, NULL);
+ if (IS_ERR(keyring))
+ return PTR_ERR(keyring);
+
+ spin_lock_irq(&new->tgcred->lock);
+ if (!new->tgcred->process_keyring) {
+ new->tgcred->process_keyring = keyring;
+ keyring = NULL;
+ ret = 0;
+ } else {
+ ret = -EEXIST;
+ }
+ spin_unlock_irq(&new->tgcred->lock);
+ key_put(keyring);
+ return ret;
+}
+
+/*
+ * Make sure a process keyring is installed for the current process. The
+ * existing process keyring is not replaced.
+ *
+ * Returns 0 if there is a process keyring by the end of this function, some
+ * error otherwise.
+ */
+static int install_process_keyring(void)
+{
+ struct cred *new;
+ int ret;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ ret = install_process_keyring_to_cred(new);
+ if (ret < 0) {
+ abort_creds(new);
+ return ret != -EEXIST ? ret : 0;
+ }
+
+ return commit_creds(new);
+}
+
+/*
+ * Install a session keyring directly to a credentials struct.
+ */
+int install_session_keyring_to_cred(struct cred *cred, struct key *keyring)
+{
+ unsigned long flags;
+ struct key *old;
+
+ might_sleep();
+
+ /* create an empty session keyring */
+ if (!keyring) {
+ flags = KEY_ALLOC_QUOTA_OVERRUN;
+ if (cred->tgcred->session_keyring)
+ flags = KEY_ALLOC_IN_QUOTA;
+
+ keyring = keyring_alloc("_ses", cred->uid, cred->gid,
+ cred, flags, NULL);
+ if (IS_ERR(keyring))
+ return PTR_ERR(keyring);
+ } else {
+ atomic_inc(&keyring->usage);
+ }
+
+ /* install the keyring */
+ spin_lock_irq(&cred->tgcred->lock);
+ old = cred->tgcred->session_keyring;
+ rcu_assign_pointer(cred->tgcred->session_keyring, keyring);
+ spin_unlock_irq(&cred->tgcred->lock);
+
+ /* we're using RCU on the pointer, but there's no point synchronising
+ * on it if it didn't previously point to anything */
+ if (old) {
+ synchronize_rcu();
+ key_put(old);
+ }
+
+ return 0;
+}
+
+/*
+ * Install a session keyring, discarding the old one. If a keyring is not
+ * supplied, an empty one is invented.
+ */
+static int install_session_keyring(struct key *keyring)
+{
+ struct cred *new;
+ int ret;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+
+ ret = install_session_keyring_to_cred(new, NULL);
+ if (ret < 0) {
+ abort_creds(new);
+ return ret;
+ }
+
+ return commit_creds(new);
+}
+
+/*
+ * Handle the fsuid changing.
+ */
+void key_fsuid_changed(struct task_struct *tsk)
+{
+ /* update the ownership of the thread keyring */
+ BUG_ON(!tsk->cred);
+ if (tsk->cred->thread_keyring) {
+ down_write(&tsk->cred->thread_keyring->sem);
+ tsk->cred->thread_keyring->uid = tsk->cred->fsuid;
+ up_write(&tsk->cred->thread_keyring->sem);
+ }
+}
+
+/*
+ * Handle the fsgid changing.
+ */
+void key_fsgid_changed(struct task_struct *tsk)
+{
+ /* update the ownership of the thread keyring */
+ BUG_ON(!tsk->cred);
+ if (tsk->cred->thread_keyring) {
+ down_write(&tsk->cred->thread_keyring->sem);
+ tsk->cred->thread_keyring->gid = tsk->cred->fsgid;
+ up_write(&tsk->cred->thread_keyring->sem);
+ }
+}
+
+/*
+ * Search the process keyrings attached to the supplied cred for the first
+ * matching key.
+ *
+ * The search criteria are the type and the match function. The description is
+ * given to the match function as a parameter, but doesn't otherwise influence
+ * the search. Typically the match function will compare the description
+ * parameter to the key's description.
+ *
+ * This can only search keyrings that grant Search permission to the supplied
+ * credentials. Keyrings linked to searched keyrings will also be searched if
+ * they grant Search permission too. Keys can only be found if they grant
+ * Search permission to the credentials.
+ *
+ * Returns a pointer to the key with the key usage count incremented if
+ * successful, -EAGAIN if we didn't find any matching key or -ENOKEY if we only
+ * matched negative keys.
+ *
+ * In the case of a successful return, the possession attribute is set on the
+ * returned key reference.
+ */
+key_ref_t search_my_process_keyrings(struct key_type *type,
+ const void *description,
+ key_match_func_t match,
+ bool no_state_check,
+ const struct cred *cred)
+{
+ key_ref_t key_ref, ret, err;
+
+ /* we want to return -EAGAIN or -ENOKEY if any of the keyrings were
+ * searchable, but we failed to find a key or we found a negative key;
+ * otherwise we want to return a sample error (probably -EACCES) if
+ * none of the keyrings were searchable
+ *
+ * in terms of priority: success > -ENOKEY > -EAGAIN > other error
+ */
+ key_ref = NULL;
+ ret = NULL;
+ err = ERR_PTR(-EAGAIN);
+
+ /* search the thread keyring first */
+ if (cred->thread_keyring) {
+ key_ref = keyring_search_aux(
+ make_key_ref(cred->thread_keyring, 1),
+ cred, type, description, match, no_state_check);
+ if (!IS_ERR(key_ref))
+ goto found;
+
+ switch (PTR_ERR(key_ref)) {
+ case -EAGAIN: /* no key */
+ if (ret)
+ break;
+ case -ENOKEY: /* negative key */
+ ret = key_ref;
+ break;
+ default:
+ err = key_ref;
+ break;
+ }
+ }
+
+ /* search the process keyring second */
+ if (cred->tgcred->process_keyring) {
+ key_ref = keyring_search_aux(
+ make_key_ref(cred->tgcred->process_keyring, 1),
+ cred, type, description, match, no_state_check);
+ if (!IS_ERR(key_ref))
+ goto found;
+
+ switch (PTR_ERR(key_ref)) {
+ case -EAGAIN: /* no key */
+ if (ret)
+ break;
+ case -ENOKEY: /* negative key */
+ ret = key_ref;
+ break;
+ default:
+ err = key_ref;
+ break;
+ }
+ }
+
+ /* search the session keyring */
+ if (cred->tgcred->session_keyring) {
+ rcu_read_lock();
+ key_ref = keyring_search_aux(
+ make_key_ref(rcu_dereference(
+ cred->tgcred->session_keyring),
+ 1),
+ cred, type, description, match, no_state_check);
+ rcu_read_unlock();
+
+ if (!IS_ERR(key_ref))
+ goto found;
+
+ switch (PTR_ERR(key_ref)) {
+ case -EAGAIN: /* no key */
+ if (ret)
+ break;
+ case -ENOKEY: /* negative key */
+ ret = key_ref;
+ break;
+ default:
+ err = key_ref;
+ break;
+ }
+ }
+ /* or search the user-session keyring */
+ else if (cred->user->session_keyring) {
+ key_ref = keyring_search_aux(
+ make_key_ref(cred->user->session_keyring, 1),
+ cred, type, description, match, no_state_check);
+ if (!IS_ERR(key_ref))
+ goto found;
+
+ switch (PTR_ERR(key_ref)) {
+ case -EAGAIN: /* no key */
+ if (ret)
+ break;
+ case -ENOKEY: /* negative key */
+ ret = key_ref;
+ break;
+ default:
+ err = key_ref;
+ break;
+ }
+ }
+
+ /* no key - decide on the error we're going to go for */
+ key_ref = ret ? ret : err;
+
+found:
+ return key_ref;
+}
+
+/*
+ * Search the process keyrings attached to the supplied cred for the first
+ * matching key in the manner of search_my_process_keyrings(), but also search
+ * the keys attached to the assumed authorisation key using its credentials if
+ * one is available.
+ *
+ * Return same as search_my_process_keyrings().
+ */
+key_ref_t search_process_keyrings(struct key_type *type,
+ const void *description,
+ key_match_func_t match,
+ const struct cred *cred)
+{
+ struct request_key_auth *rka;
+ key_ref_t key_ref, ret = ERR_PTR(-EACCES), err;
+
+ might_sleep();
+
+ key_ref = search_my_process_keyrings(type, description, match,
+ false, cred);
+ if (!IS_ERR(key_ref))
+ goto found;
+ err = key_ref;
+
+ /* if this process has an instantiation authorisation key, then we also
+ * search the keyrings of the process mentioned there
+ * - we don't permit access to request_key auth keys via this method
+ */
+ if (cred->request_key_auth &&
+ cred == current_cred() &&
+ type != &key_type_request_key_auth
+ ) {
+ /* defend against the auth key being revoked */
+ down_read(&cred->request_key_auth->sem);
+
+ if (key_validate(cred->request_key_auth) == 0) {
+ rka = cred->request_key_auth->payload.data;
+
+ key_ref = search_process_keyrings(type, description,
+ match, rka->cred);
+
+ up_read(&cred->request_key_auth->sem);
+
+ if (!IS_ERR(key_ref))
+ goto found;
+
+ ret = key_ref;
+ } else {
+ up_read(&cred->request_key_auth->sem);
+ }
+ }
+
+ /* no key - decide on the error we're going to go for */
+ if (err == ERR_PTR(-ENOKEY) || ret == ERR_PTR(-ENOKEY))
+ key_ref = ERR_PTR(-ENOKEY);
+ else if (err == ERR_PTR(-EACCES))
+ key_ref = ret;
+ else
+ key_ref = err;
+
+found:
+ return key_ref;
+}
+
+/*
+ * See if the key we're looking at is the target key.
+ */
+int lookup_user_key_possessed(const struct key *key, const void *target)
+{
+ return key == target;
+}
+
+/*
+ * Look up a key ID given us by userspace with a given permissions mask to get
+ * the key it refers to.
+ *
+ * Flags can be passed to request that special keyrings be created if referred
+ * to directly, to permit partially constructed keys to be found and to skip
+ * validity and permission checks on the found key.
+ *
+ * Returns a pointer to the key with an incremented usage count if successful;
+ * -EINVAL if the key ID is invalid; -ENOKEY if the key ID does not correspond
+ * to a key or the best found key was a negative key; -EKEYREVOKED or
+ * -EKEYEXPIRED if the best found key was revoked or expired; -EACCES if the
+ * found key doesn't grant the requested permit or the LSM denied access to it;
+ * or -ENOMEM if a special keyring couldn't be created.
+ *
+ * In the case of a successful return, the possession attribute is set on the
+ * returned key reference.
+ */
+key_ref_t lookup_user_key(key_serial_t id, unsigned long lflags,
+ key_perm_t perm)
+{
+ struct request_key_auth *rka;
+ const struct cred *cred;
+ struct key *key;
+ key_ref_t key_ref, skey_ref;
+ int ret;
+
+try_again:
+ cred = get_current_cred();
+ key_ref = ERR_PTR(-ENOKEY);
+
+ switch (id) {
+ case KEY_SPEC_THREAD_KEYRING:
+ if (!cred->thread_keyring) {
+ if (!(lflags & KEY_LOOKUP_CREATE))
+ goto error;
+
+ ret = install_thread_keyring();
+ if (ret < 0) {
+ key_ref = ERR_PTR(ret);
+ goto error;
+ }
+ goto reget_creds;
+ }
+
+ key = cred->thread_keyring;
+ atomic_inc(&key->usage);
+ key_ref = make_key_ref(key, 1);
+ break;
+
+ case KEY_SPEC_PROCESS_KEYRING:
+ if (!cred->tgcred->process_keyring) {
+ if (!(lflags & KEY_LOOKUP_CREATE))
+ goto error;
+
+ ret = install_process_keyring();
+ if (ret < 0) {
+ key_ref = ERR_PTR(ret);
+ goto error;
+ }
+ goto reget_creds;
+ }
+
+ key = cred->tgcred->process_keyring;
+ atomic_inc(&key->usage);
+ key_ref = make_key_ref(key, 1);
+ break;
+
+ case KEY_SPEC_SESSION_KEYRING:
+ if (!cred->tgcred->session_keyring) {
+ /* always install a session keyring upon access if one
+ * doesn't exist yet */
+ ret = install_user_keyrings();
+ if (ret < 0)
+ goto error;
+ ret = install_session_keyring(
+ cred->user->session_keyring);
+
+ if (ret < 0)
+ goto error;
+ goto reget_creds;
+ }
+
+ rcu_read_lock();
+ key = rcu_dereference(cred->tgcred->session_keyring);
+ atomic_inc(&key->usage);
+ rcu_read_unlock();
+ key_ref = make_key_ref(key, 1);
+ break;
+
+ case KEY_SPEC_USER_KEYRING:
+ if (!cred->user->uid_keyring) {
+ ret = install_user_keyrings();
+ if (ret < 0)
+ goto error;
+ }
+
+ key = cred->user->uid_keyring;
+ atomic_inc(&key->usage);
+ key_ref = make_key_ref(key, 1);
+ break;
+
+ case KEY_SPEC_USER_SESSION_KEYRING:
+ if (!cred->user->session_keyring) {
+ ret = install_user_keyrings();
+ if (ret < 0)
+ goto error;
+ }
+
+ key = cred->user->session_keyring;
+ atomic_inc(&key->usage);
+ key_ref = make_key_ref(key, 1);
+ break;
+
+ case KEY_SPEC_GROUP_KEYRING:
+ /* group keyrings are not yet supported */
+ key_ref = ERR_PTR(-EINVAL);
+ goto error;
+
+ case KEY_SPEC_REQKEY_AUTH_KEY:
+ key = cred->request_key_auth;
+ if (!key)
+ goto error;
+
+ atomic_inc(&key->usage);
+ key_ref = make_key_ref(key, 1);
+ break;
+
+ case KEY_SPEC_REQUESTOR_KEYRING:
+ if (!cred->request_key_auth)
+ goto error;
+
+ down_read(&cred->request_key_auth->sem);
+ if (cred->request_key_auth->flags & KEY_FLAG_REVOKED) {
+ key_ref = ERR_PTR(-EKEYREVOKED);
+ key = NULL;
+ } else {
+ rka = cred->request_key_auth->payload.data;
+ key = rka->dest_keyring;
+ atomic_inc(&key->usage);
+ }
+ up_read(&cred->request_key_auth->sem);
+ if (!key)
+ goto error;
+ key_ref = make_key_ref(key, 1);
+ break;
+
+ default:
+ key_ref = ERR_PTR(-EINVAL);
+ if (id < 1)
+ goto error;
+
+ key = key_lookup(id);
+ if (IS_ERR(key)) {
+ key_ref = ERR_CAST(key);
+ goto error;
+ }
+
+ key_ref = make_key_ref(key, 0);
+
+ /* check to see if we possess the key */
+ skey_ref = search_process_keyrings(key->type, key,
+ lookup_user_key_possessed,
+ cred);
+
+ if (!IS_ERR(skey_ref)) {
+ key_put(key);
+ key_ref = skey_ref;
+ }
+
+ break;
+ }
+
+ /* unlink does not use the nominated key in any way, so can skip all
+ * the permission checks as it is only concerned with the keyring */
+ if (lflags & KEY_LOOKUP_FOR_UNLINK) {
+ ret = 0;
+ goto error;
+ }
+
+ if (!(lflags & KEY_LOOKUP_PARTIAL)) {
+ ret = wait_for_key_construction(key, true);
+ switch (ret) {
+ case -ERESTARTSYS:
+ goto invalid_key;
+ default:
+ if (perm)
+ goto invalid_key;
+ case 0:
+ break;
+ }
+ } else if (perm) {
+ ret = key_validate(key);
+ if (ret < 0)
+ goto invalid_key;
+ }
+
+ ret = -EIO;
+ if (!(lflags & KEY_LOOKUP_PARTIAL) &&
+ !test_bit(KEY_FLAG_INSTANTIATED, &key->flags))
+ goto invalid_key;
+
+ /* check the permissions */
+ ret = key_task_permission(key_ref, cred, perm);
+ if (ret < 0)
+ goto invalid_key;
+
+error:
+ put_cred(cred);
+ return key_ref;
+
+invalid_key:
+ key_ref_put(key_ref);
+ key_ref = ERR_PTR(ret);
+ goto error;
+
+ /* if we attempted to install a keyring, then it may have caused new
+ * creds to be installed */
+reget_creds:
+ put_cred(cred);
+ goto try_again;
+}
+
+/*
+ * Join the named keyring as the session keyring if possible else attempt to
+ * create a new one of that name and join that.
+ *
+ * If the name is NULL, an empty anonymous keyring will be installed as the
+ * session keyring.
+ *
+ * Named session keyrings are joined with a semaphore held to prevent the
+ * keyrings from going away whilst the attempt is made to going them and also
+ * to prevent a race in creating compatible session keyrings.
+ */
+long join_session_keyring(const char *name)
+{
+ const struct cred *old;
+ struct cred *new;
+ struct key *keyring;
+ long ret, serial;
+
+ /* only permit this if there's a single thread in the thread group -
+ * this avoids us having to adjust the creds on all threads and risking
+ * ENOMEM */
+ if (!current_is_single_threaded())
+ return -EMLINK;
+
+ new = prepare_creds();
+ if (!new)
+ return -ENOMEM;
+ old = current_cred();
+
+ /* if no name is provided, install an anonymous keyring */
+ if (!name) {
+ ret = install_session_keyring_to_cred(new, NULL);
+ if (ret < 0)
+ goto error;
+
+ serial = new->tgcred->session_keyring->serial;
+ ret = commit_creds(new);
+ if (ret == 0)
+ ret = serial;
+ goto okay;
+ }
+
+ /* allow the user to join or create a named keyring */
+ mutex_lock(&key_session_mutex);
+
+ /* look for an existing keyring of this name */
+ keyring = find_keyring_by_name(name, false);
+ if (PTR_ERR(keyring) == -ENOKEY) {
+ /* not found - try and create a new one */
+ keyring = keyring_alloc(name, old->uid, old->gid, old,
+ KEY_ALLOC_IN_QUOTA, NULL);
+ if (IS_ERR(keyring)) {
+ ret = PTR_ERR(keyring);
+ goto error2;
+ }
+ } else if (IS_ERR(keyring)) {
+ ret = PTR_ERR(keyring);
+ goto error2;
+ }
+
+ /* we've got a keyring - now to install it */
+ ret = install_session_keyring_to_cred(new, keyring);
+ if (ret < 0)
+ goto error2;
+
+ commit_creds(new);
+ mutex_unlock(&key_session_mutex);
+
+ ret = keyring->serial;
+ key_put(keyring);
+okay:
+ return ret;
+
+error2:
+ mutex_unlock(&key_session_mutex);
+error:
+ abort_creds(new);
+ return ret;
+}
+
+/*
+ * Replace a process's session keyring on behalf of one of its children when
+ * the target process is about to resume userspace execution.
+ */
+void key_replace_session_keyring(void)
+{
+ const struct cred *old;
+ struct cred *new;
+
+ if (!current->replacement_session_keyring)
+ return;
+
+ write_lock_irq(&tasklist_lock);
+ new = current->replacement_session_keyring;
+ current->replacement_session_keyring = NULL;
+ write_unlock_irq(&tasklist_lock);
+
+ if (!new)
+ return;
+
+ old = current_cred();
+ new-> uid = old-> uid;
+ new-> euid = old-> euid;
+ new-> suid = old-> suid;
+ new->fsuid = old->fsuid;
+ new-> gid = old-> gid;
+ new-> egid = old-> egid;
+ new-> sgid = old-> sgid;
+ new->fsgid = old->fsgid;
+ new->user = get_uid(old->user);
+ new->user_ns = new->user->user_ns;
+ new->group_info = get_group_info(old->group_info);
+
+ new->securebits = old->securebits;
+ new->cap_inheritable = old->cap_inheritable;
+ new->cap_permitted = old->cap_permitted;
+ new->cap_effective = old->cap_effective;
+ new->cap_bset = old->cap_bset;
+
+ new->jit_keyring = old->jit_keyring;
+ new->thread_keyring = key_get(old->thread_keyring);
+ new->tgcred->tgid = old->tgcred->tgid;
+ new->tgcred->process_keyring = key_get(old->tgcred->process_keyring);
+
+ security_transfer_creds(new, old);
+
+ commit_creds(new);
+}
diff --git a/security/keys/request_key.c b/security/keys/request_key.c
new file mode 100644
index 00000000..82465328
--- /dev/null
+++ b/security/keys/request_key.c
@@ -0,0 +1,713 @@
+/* Request a key from userspace
+ *
+ * Copyright (C) 2004-2007 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * See Documentation/security/keys-request-key.txt
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/kmod.h>
+#include <linux/err.h>
+#include <linux/keyctl.h>
+#include <linux/slab.h>
+#include "internal.h"
+
+#define key_negative_timeout 60 /* default timeout on a negative key's existence */
+
+/*
+ * wait_on_bit() sleep function for uninterruptible waiting
+ */
+static int key_wait_bit(void *flags)
+{
+ schedule();
+ return 0;
+}
+
+/*
+ * wait_on_bit() sleep function for interruptible waiting
+ */
+static int key_wait_bit_intr(void *flags)
+{
+ schedule();
+ return signal_pending(current) ? -ERESTARTSYS : 0;
+}
+
+/**
+ * complete_request_key - Complete the construction of a key.
+ * @cons: The key construction record.
+ * @error: The success or failute of the construction.
+ *
+ * Complete the attempt to construct a key. The key will be negated
+ * if an error is indicated. The authorisation key will be revoked
+ * unconditionally.
+ */
+void complete_request_key(struct key_construction *cons, int error)
+{
+ kenter("{%d,%d},%d", cons->key->serial, cons->authkey->serial, error);
+
+ if (error < 0)
+ key_negate_and_link(cons->key, key_negative_timeout, NULL,
+ cons->authkey);
+ else
+ key_revoke(cons->authkey);
+
+ key_put(cons->key);
+ key_put(cons->authkey);
+ kfree(cons);
+}
+EXPORT_SYMBOL(complete_request_key);
+
+/*
+ * Initialise a usermode helper that is going to have a specific session
+ * keyring.
+ *
+ * This is called in context of freshly forked kthread before kernel_execve(),
+ * so we can simply install the desired session_keyring at this point.
+ */
+static int umh_keys_init(struct subprocess_info *info, struct cred *cred)
+{
+ struct key *keyring = info->data;
+
+ return install_session_keyring_to_cred(cred, keyring);
+}
+
+/*
+ * Clean up a usermode helper with session keyring.
+ */
+static void umh_keys_cleanup(struct subprocess_info *info)
+{
+ struct key *keyring = info->data;
+ key_put(keyring);
+}
+
+/*
+ * Call a usermode helper with a specific session keyring.
+ */
+static int call_usermodehelper_keys(char *path, char **argv, char **envp,
+ struct key *session_keyring, enum umh_wait wait)
+{
+ gfp_t gfp_mask = (wait == UMH_NO_WAIT) ? GFP_ATOMIC : GFP_KERNEL;
+ struct subprocess_info *info =
+ call_usermodehelper_setup(path, argv, envp, gfp_mask);
+
+ if (!info)
+ return -ENOMEM;
+
+ call_usermodehelper_setfns(info, umh_keys_init, umh_keys_cleanup,
+ key_get(session_keyring));
+ return call_usermodehelper_exec(info, wait);
+}
+
+/*
+ * Request userspace finish the construction of a key
+ * - execute "/sbin/request-key <op> <key> <uid> <gid> <keyring> <keyring> <keyring>"
+ */
+static int call_sbin_request_key(struct key_construction *cons,
+ const char *op,
+ void *aux)
+{
+ const struct cred *cred = current_cred();
+ key_serial_t prkey, sskey;
+ struct key *key = cons->key, *authkey = cons->authkey, *keyring,
+ *session;
+ char *argv[9], *envp[3], uid_str[12], gid_str[12];
+ char key_str[12], keyring_str[3][12];
+ char desc[20];
+ int ret, i;
+
+ kenter("{%d},{%d},%s", key->serial, authkey->serial, op);
+
+ ret = install_user_keyrings();
+ if (ret < 0)
+ goto error_alloc;
+
+ /* allocate a new session keyring */
+ sprintf(desc, "_req.%u", key->serial);
+
+ cred = get_current_cred();
+ keyring = keyring_alloc(desc, cred->fsuid, cred->fsgid, cred,
+ KEY_ALLOC_QUOTA_OVERRUN, NULL);
+ put_cred(cred);
+ if (IS_ERR(keyring)) {
+ ret = PTR_ERR(keyring);
+ goto error_alloc;
+ }
+
+ /* attach the auth key to the session keyring */
+ ret = key_link(keyring, authkey);
+ if (ret < 0)
+ goto error_link;
+
+ /* record the UID and GID */
+ sprintf(uid_str, "%d", cred->fsuid);
+ sprintf(gid_str, "%d", cred->fsgid);
+
+ /* we say which key is under construction */
+ sprintf(key_str, "%d", key->serial);
+
+ /* we specify the process's default keyrings */
+ sprintf(keyring_str[0], "%d",
+ cred->thread_keyring ? cred->thread_keyring->serial : 0);
+
+ prkey = 0;
+ if (cred->tgcred->process_keyring)
+ prkey = cred->tgcred->process_keyring->serial;
+ sprintf(keyring_str[1], "%d", prkey);
+
+ rcu_read_lock();
+ session = rcu_dereference(cred->tgcred->session_keyring);
+ if (!session)
+ session = cred->user->session_keyring;
+ sskey = session->serial;
+ rcu_read_unlock();
+
+ sprintf(keyring_str[2], "%d", sskey);
+
+ /* set up a minimal environment */
+ i = 0;
+ envp[i++] = "HOME=/";
+ envp[i++] = "PATH=/sbin:/bin:/usr/sbin:/usr/bin";
+ envp[i] = NULL;
+
+ /* set up the argument list */
+ i = 0;
+ argv[i++] = "/sbin/request-key";
+ argv[i++] = (char *) op;
+ argv[i++] = key_str;
+ argv[i++] = uid_str;
+ argv[i++] = gid_str;
+ argv[i++] = keyring_str[0];
+ argv[i++] = keyring_str[1];
+ argv[i++] = keyring_str[2];
+ argv[i] = NULL;
+
+ /* do it */
+ ret = call_usermodehelper_keys(argv[0], argv, envp, keyring,
+ UMH_WAIT_PROC);
+ kdebug("usermode -> 0x%x", ret);
+ if (ret >= 0) {
+ /* ret is the exit/wait code */
+ if (test_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags) ||
+ key_validate(key) < 0)
+ ret = -ENOKEY;
+ else
+ /* ignore any errors from userspace if the key was
+ * instantiated */
+ ret = 0;
+ }
+
+error_link:
+ key_put(keyring);
+
+error_alloc:
+ complete_request_key(cons, ret);
+ kleave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * Call out to userspace for key construction.
+ *
+ * Program failure is ignored in favour of key status.
+ */
+static int construct_key(struct key *key, const void *callout_info,
+ size_t callout_len, void *aux,
+ struct key *dest_keyring)
+{
+ struct key_construction *cons;
+ request_key_actor_t actor;
+ struct key *authkey;
+ int ret;
+
+ kenter("%d,%p,%zu,%p", key->serial, callout_info, callout_len, aux);
+
+ cons = kmalloc(sizeof(*cons), GFP_KERNEL);
+ if (!cons)
+ return -ENOMEM;
+
+ /* allocate an authorisation key */
+ authkey = request_key_auth_new(key, callout_info, callout_len,
+ dest_keyring);
+ if (IS_ERR(authkey)) {
+ kfree(cons);
+ ret = PTR_ERR(authkey);
+ authkey = NULL;
+ } else {
+ cons->authkey = key_get(authkey);
+ cons->key = key_get(key);
+
+ /* make the call */
+ actor = call_sbin_request_key;
+ if (key->type->request_key)
+ actor = key->type->request_key;
+
+ ret = actor(cons, "create", aux);
+
+ /* check that the actor called complete_request_key() prior to
+ * returning an error */
+ WARN_ON(ret < 0 &&
+ !test_bit(KEY_FLAG_REVOKED, &authkey->flags));
+ key_put(authkey);
+ }
+
+ kleave(" = %d", ret);
+ return ret;
+}
+
+/*
+ * Get the appropriate destination keyring for the request.
+ *
+ * The keyring selected is returned with an extra reference upon it which the
+ * caller must release.
+ */
+static void construct_get_dest_keyring(struct key **_dest_keyring)
+{
+ struct request_key_auth *rka;
+ const struct cred *cred = current_cred();
+ struct key *dest_keyring = *_dest_keyring, *authkey;
+
+ kenter("%p", dest_keyring);
+
+ /* find the appropriate keyring */
+ if (dest_keyring) {
+ /* the caller supplied one */
+ key_get(dest_keyring);
+ } else {
+ /* use a default keyring; falling through the cases until we
+ * find one that we actually have */
+ switch (cred->jit_keyring) {
+ case KEY_REQKEY_DEFL_DEFAULT:
+ case KEY_REQKEY_DEFL_REQUESTOR_KEYRING:
+ if (cred->request_key_auth) {
+ authkey = cred->request_key_auth;
+ down_read(&authkey->sem);
+ rka = authkey->payload.data;
+ if (!test_bit(KEY_FLAG_REVOKED,
+ &authkey->flags))
+ dest_keyring =
+ key_get(rka->dest_keyring);
+ up_read(&authkey->sem);
+ if (dest_keyring)
+ break;
+ }
+
+ case KEY_REQKEY_DEFL_THREAD_KEYRING:
+ dest_keyring = key_get(cred->thread_keyring);
+ if (dest_keyring)
+ break;
+
+ case KEY_REQKEY_DEFL_PROCESS_KEYRING:
+ dest_keyring = key_get(cred->tgcred->process_keyring);
+ if (dest_keyring)
+ break;
+
+ case KEY_REQKEY_DEFL_SESSION_KEYRING:
+ rcu_read_lock();
+ dest_keyring = key_get(
+ rcu_dereference(cred->tgcred->session_keyring));
+ rcu_read_unlock();
+
+ if (dest_keyring)
+ break;
+
+ case KEY_REQKEY_DEFL_USER_SESSION_KEYRING:
+ dest_keyring =
+ key_get(cred->user->session_keyring);
+ break;
+
+ case KEY_REQKEY_DEFL_USER_KEYRING:
+ dest_keyring = key_get(cred->user->uid_keyring);
+ break;
+
+ case KEY_REQKEY_DEFL_GROUP_KEYRING:
+ default:
+ BUG();
+ }
+ }
+
+ *_dest_keyring = dest_keyring;
+ kleave(" [dk %d]", key_serial(dest_keyring));
+ return;
+}
+
+/*
+ * Allocate a new key in under-construction state and attempt to link it in to
+ * the requested keyring.
+ *
+ * May return a key that's already under construction instead if there was a
+ * race between two thread calling request_key().
+ */
+static int construct_alloc_key(struct key_type *type,
+ const char *description,
+ struct key *dest_keyring,
+ unsigned long flags,
+ struct key_user *user,
+ struct key **_key)
+{
+ const struct cred *cred = current_cred();
+ unsigned long prealloc;
+ struct key *key;
+ key_ref_t key_ref;
+ int ret;
+
+ kenter("%s,%s,,,", type->name, description);
+
+ *_key = NULL;
+ mutex_lock(&user->cons_lock);
+
+ key = key_alloc(type, description, cred->fsuid, cred->fsgid, cred,
+ KEY_POS_ALL, flags);
+ if (IS_ERR(key))
+ goto alloc_failed;
+
+ set_bit(KEY_FLAG_USER_CONSTRUCT, &key->flags);
+
+ if (dest_keyring) {
+ ret = __key_link_begin(dest_keyring, type, description,
+ &prealloc);
+ if (ret < 0)
+ goto link_prealloc_failed;
+ }
+
+ /* attach the key to the destination keyring under lock, but we do need
+ * to do another check just in case someone beat us to it whilst we
+ * waited for locks */
+ mutex_lock(&key_construction_mutex);
+
+ key_ref = search_process_keyrings(type, description, type->match, cred);
+ if (!IS_ERR(key_ref))
+ goto key_already_present;
+
+ if (dest_keyring)
+ __key_link(dest_keyring, key, &prealloc);
+
+ mutex_unlock(&key_construction_mutex);
+ if (dest_keyring)
+ __key_link_end(dest_keyring, type, prealloc);
+ mutex_unlock(&user->cons_lock);
+ *_key = key;
+ kleave(" = 0 [%d]", key_serial(key));
+ return 0;
+
+ /* the key is now present - we tell the caller that we found it by
+ * returning -EINPROGRESS */
+key_already_present:
+ key_put(key);
+ mutex_unlock(&key_construction_mutex);
+ key = key_ref_to_ptr(key_ref);
+ if (dest_keyring) {
+ ret = __key_link_check_live_key(dest_keyring, key);
+ if (ret == 0)
+ __key_link(dest_keyring, key, &prealloc);
+ __key_link_end(dest_keyring, type, prealloc);
+ if (ret < 0)
+ goto link_check_failed;
+ }
+ mutex_unlock(&user->cons_lock);
+ *_key = key;
+ kleave(" = -EINPROGRESS [%d]", key_serial(key));
+ return -EINPROGRESS;
+
+link_check_failed:
+ mutex_unlock(&user->cons_lock);
+ key_put(key);
+ kleave(" = %d [linkcheck]", ret);
+ return ret;
+
+link_prealloc_failed:
+ mutex_unlock(&user->cons_lock);
+ kleave(" = %d [prelink]", ret);
+ return ret;
+
+alloc_failed:
+ mutex_unlock(&user->cons_lock);
+ kleave(" = %ld", PTR_ERR(key));
+ return PTR_ERR(key);
+}
+
+/*
+ * Commence key construction.
+ */
+static struct key *construct_key_and_link(struct key_type *type,
+ const char *description,
+ const char *callout_info,
+ size_t callout_len,
+ void *aux,
+ struct key *dest_keyring,
+ unsigned long flags)
+{
+ struct key_user *user;
+ struct key *key;
+ int ret;
+
+ kenter("");
+
+ user = key_user_lookup(current_fsuid(), current_user_ns());
+ if (!user)
+ return ERR_PTR(-ENOMEM);
+
+ construct_get_dest_keyring(&dest_keyring);
+
+ ret = construct_alloc_key(type, description, dest_keyring, flags, user,
+ &key);
+ key_user_put(user);
+
+ if (ret == 0) {
+ ret = construct_key(key, callout_info, callout_len, aux,
+ dest_keyring);
+ if (ret < 0) {
+ kdebug("cons failed");
+ goto construction_failed;
+ }
+ } else if (ret == -EINPROGRESS) {
+ ret = 0;
+ } else {
+ goto couldnt_alloc_key;
+ }
+
+ key_put(dest_keyring);
+ kleave(" = key %d", key_serial(key));
+ return key;
+
+construction_failed:
+ key_negate_and_link(key, key_negative_timeout, NULL, NULL);
+ key_put(key);
+couldnt_alloc_key:
+ key_put(dest_keyring);
+ kleave(" = %d", ret);
+ return ERR_PTR(ret);
+}
+
+/**
+ * request_key_and_link - Request a key and cache it in a keyring.
+ * @type: The type of key we want.
+ * @description: The searchable description of the key.
+ * @callout_info: The data to pass to the instantiation upcall (or NULL).
+ * @callout_len: The length of callout_info.
+ * @aux: Auxiliary data for the upcall.
+ * @dest_keyring: Where to cache the key.
+ * @flags: Flags to key_alloc().
+ *
+ * A key matching the specified criteria is searched for in the process's
+ * keyrings and returned with its usage count incremented if found. Otherwise,
+ * if callout_info is not NULL, a key will be allocated and some service
+ * (probably in userspace) will be asked to instantiate it.
+ *
+ * If successfully found or created, the key will be linked to the destination
+ * keyring if one is provided.
+ *
+ * Returns a pointer to the key if successful; -EACCES, -ENOKEY, -EKEYREVOKED
+ * or -EKEYEXPIRED if an inaccessible, negative, revoked or expired key was
+ * found; -ENOKEY if no key was found and no @callout_info was given; -EDQUOT
+ * if insufficient key quota was available to create a new key; or -ENOMEM if
+ * insufficient memory was available.
+ *
+ * If the returned key was created, then it may still be under construction,
+ * and wait_for_key_construction() should be used to wait for that to complete.
+ */
+struct key *request_key_and_link(struct key_type *type,
+ const char *description,
+ const void *callout_info,
+ size_t callout_len,
+ void *aux,
+ struct key *dest_keyring,
+ unsigned long flags)
+{
+ const struct cred *cred = current_cred();
+ struct key *key;
+ key_ref_t key_ref;
+ int ret;
+
+ kenter("%s,%s,%p,%zu,%p,%p,%lx",
+ type->name, description, callout_info, callout_len, aux,
+ dest_keyring, flags);
+
+ /* search all the process keyrings for a key */
+ key_ref = search_process_keyrings(type, description, type->match, cred);
+
+ if (!IS_ERR(key_ref)) {
+ key = key_ref_to_ptr(key_ref);
+ if (dest_keyring) {
+ construct_get_dest_keyring(&dest_keyring);
+ ret = key_link(dest_keyring, key);
+ key_put(dest_keyring);
+ if (ret < 0) {
+ key_put(key);
+ key = ERR_PTR(ret);
+ goto error;
+ }
+ }
+ } else if (PTR_ERR(key_ref) != -EAGAIN) {
+ key = ERR_CAST(key_ref);
+ } else {
+ /* the search failed, but the keyrings were searchable, so we
+ * should consult userspace if we can */
+ key = ERR_PTR(-ENOKEY);
+ if (!callout_info)
+ goto error;
+
+ key = construct_key_and_link(type, description, callout_info,
+ callout_len, aux, dest_keyring,
+ flags);
+ }
+
+error:
+ kleave(" = %p", key);
+ return key;
+}
+
+/**
+ * wait_for_key_construction - Wait for construction of a key to complete
+ * @key: The key being waited for.
+ * @intr: Whether to wait interruptibly.
+ *
+ * Wait for a key to finish being constructed.
+ *
+ * Returns 0 if successful; -ERESTARTSYS if the wait was interrupted; -ENOKEY
+ * if the key was negated; or -EKEYREVOKED or -EKEYEXPIRED if the key was
+ * revoked or expired.
+ */
+int wait_for_key_construction(struct key *key, bool intr)
+{
+ int ret;
+
+ ret = wait_on_bit(&key->flags, KEY_FLAG_USER_CONSTRUCT,
+ intr ? key_wait_bit_intr : key_wait_bit,
+ intr ? TASK_INTERRUPTIBLE : TASK_UNINTERRUPTIBLE);
+ if (ret < 0)
+ return ret;
+ if (test_bit(KEY_FLAG_NEGATIVE, &key->flags))
+ return key->type_data.reject_error;
+ return key_validate(key);
+}
+EXPORT_SYMBOL(wait_for_key_construction);
+
+/**
+ * request_key - Request a key and wait for construction
+ * @type: Type of key.
+ * @description: The searchable description of the key.
+ * @callout_info: The data to pass to the instantiation upcall (or NULL).
+ *
+ * As for request_key_and_link() except that it does not add the returned key
+ * to a keyring if found, new keys are always allocated in the user's quota,
+ * the callout_info must be a NUL-terminated string and no auxiliary data can
+ * be passed.
+ *
+ * Furthermore, it then works as wait_for_key_construction() to wait for the
+ * completion of keys undergoing construction with a non-interruptible wait.
+ */
+struct key *request_key(struct key_type *type,
+ const char *description,
+ const char *callout_info)
+{
+ struct key *key;
+ size_t callout_len = 0;
+ int ret;
+
+ if (callout_info)
+ callout_len = strlen(callout_info);
+ key = request_key_and_link(type, description, callout_info, callout_len,
+ NULL, NULL, KEY_ALLOC_IN_QUOTA);
+ if (!IS_ERR(key)) {
+ ret = wait_for_key_construction(key, false);
+ if (ret < 0) {
+ key_put(key);
+ return ERR_PTR(ret);
+ }
+ }
+ return key;
+}
+EXPORT_SYMBOL(request_key);
+
+/**
+ * request_key_with_auxdata - Request a key with auxiliary data for the upcaller
+ * @type: The type of key we want.
+ * @description: The searchable description of the key.
+ * @callout_info: The data to pass to the instantiation upcall (or NULL).
+ * @callout_len: The length of callout_info.
+ * @aux: Auxiliary data for the upcall.
+ *
+ * As for request_key_and_link() except that it does not add the returned key
+ * to a keyring if found and new keys are always allocated in the user's quota.
+ *
+ * Furthermore, it then works as wait_for_key_construction() to wait for the
+ * completion of keys undergoing construction with a non-interruptible wait.
+ */
+struct key *request_key_with_auxdata(struct key_type *type,
+ const char *description,
+ const void *callout_info,
+ size_t callout_len,
+ void *aux)
+{
+ struct key *key;
+ int ret;
+
+ key = request_key_and_link(type, description, callout_info, callout_len,
+ aux, NULL, KEY_ALLOC_IN_QUOTA);
+ if (!IS_ERR(key)) {
+ ret = wait_for_key_construction(key, false);
+ if (ret < 0) {
+ key_put(key);
+ return ERR_PTR(ret);
+ }
+ }
+ return key;
+}
+EXPORT_SYMBOL(request_key_with_auxdata);
+
+/*
+ * request_key_async - Request a key (allow async construction)
+ * @type: Type of key.
+ * @description: The searchable description of the key.
+ * @callout_info: The data to pass to the instantiation upcall (or NULL).
+ * @callout_len: The length of callout_info.
+ *
+ * As for request_key_and_link() except that it does not add the returned key
+ * to a keyring if found, new keys are always allocated in the user's quota and
+ * no auxiliary data can be passed.
+ *
+ * The caller should call wait_for_key_construction() to wait for the
+ * completion of the returned key if it is still undergoing construction.
+ */
+struct key *request_key_async(struct key_type *type,
+ const char *description,
+ const void *callout_info,
+ size_t callout_len)
+{
+ return request_key_and_link(type, description, callout_info,
+ callout_len, NULL, NULL,
+ KEY_ALLOC_IN_QUOTA);
+}
+EXPORT_SYMBOL(request_key_async);
+
+/*
+ * request a key with auxiliary data for the upcaller (allow async construction)
+ * @type: Type of key.
+ * @description: The searchable description of the key.
+ * @callout_info: The data to pass to the instantiation upcall (or NULL).
+ * @callout_len: The length of callout_info.
+ * @aux: Auxiliary data for the upcall.
+ *
+ * As for request_key_and_link() except that it does not add the returned key
+ * to a keyring if found and new keys are always allocated in the user's quota.
+ *
+ * The caller should call wait_for_key_construction() to wait for the
+ * completion of the returned key if it is still undergoing construction.
+ */
+struct key *request_key_async_with_auxdata(struct key_type *type,
+ const char *description,
+ const void *callout_info,
+ size_t callout_len,
+ void *aux)
+{
+ return request_key_and_link(type, description, callout_info,
+ callout_len, aux, NULL, KEY_ALLOC_IN_QUOTA);
+}
+EXPORT_SYMBOL(request_key_async_with_auxdata);
diff --git a/security/keys/request_key_auth.c b/security/keys/request_key_auth.c
new file mode 100644
index 00000000..6cff3752
--- /dev/null
+++ b/security/keys/request_key_auth.c
@@ -0,0 +1,265 @@
+/* Request key authorisation token key definition.
+ *
+ * Copyright (C) 2005 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ * See Documentation/security/keys-request-key.txt
+ */
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/err.h>
+#include <linux/seq_file.h>
+#include <linux/slab.h>
+#include <asm/uaccess.h>
+#include "internal.h"
+
+static int request_key_auth_instantiate(struct key *, const void *, size_t);
+static void request_key_auth_describe(const struct key *, struct seq_file *);
+static void request_key_auth_revoke(struct key *);
+static void request_key_auth_destroy(struct key *);
+static long request_key_auth_read(const struct key *, char __user *, size_t);
+
+/*
+ * The request-key authorisation key type definition.
+ */
+struct key_type key_type_request_key_auth = {
+ .name = ".request_key_auth",
+ .def_datalen = sizeof(struct request_key_auth),
+ .instantiate = request_key_auth_instantiate,
+ .describe = request_key_auth_describe,
+ .revoke = request_key_auth_revoke,
+ .destroy = request_key_auth_destroy,
+ .read = request_key_auth_read,
+};
+
+/*
+ * Instantiate a request-key authorisation key.
+ */
+static int request_key_auth_instantiate(struct key *key,
+ const void *data,
+ size_t datalen)
+{
+ key->payload.data = (struct request_key_auth *) data;
+ return 0;
+}
+
+/*
+ * Describe an authorisation token.
+ */
+static void request_key_auth_describe(const struct key *key,
+ struct seq_file *m)
+{
+ struct request_key_auth *rka = key->payload.data;
+
+ seq_puts(m, "key:");
+ seq_puts(m, key->description);
+ if (key_is_instantiated(key))
+ seq_printf(m, " pid:%d ci:%zu", rka->pid, rka->callout_len);
+}
+
+/*
+ * Read the callout_info data (retrieves the callout information).
+ * - the key's semaphore is read-locked
+ */
+static long request_key_auth_read(const struct key *key,
+ char __user *buffer, size_t buflen)
+{
+ struct request_key_auth *rka = key->payload.data;
+ size_t datalen;
+ long ret;
+
+ datalen = rka->callout_len;
+ ret = datalen;
+
+ /* we can return the data as is */
+ if (buffer && buflen > 0) {
+ if (buflen > datalen)
+ buflen = datalen;
+
+ if (copy_to_user(buffer, rka->callout_info, buflen) != 0)
+ ret = -EFAULT;
+ }
+
+ return ret;
+}
+
+/*
+ * Handle revocation of an authorisation token key.
+ *
+ * Called with the key sem write-locked.
+ */
+static void request_key_auth_revoke(struct key *key)
+{
+ struct request_key_auth *rka = key->payload.data;
+
+ kenter("{%d}", key->serial);
+
+ if (rka->cred) {
+ put_cred(rka->cred);
+ rka->cred = NULL;
+ }
+}
+
+/*
+ * Destroy an instantiation authorisation token key.
+ */
+static void request_key_auth_destroy(struct key *key)
+{
+ struct request_key_auth *rka = key->payload.data;
+
+ kenter("{%d}", key->serial);
+
+ if (rka->cred) {
+ put_cred(rka->cred);
+ rka->cred = NULL;
+ }
+
+ key_put(rka->target_key);
+ key_put(rka->dest_keyring);
+ kfree(rka->callout_info);
+ kfree(rka);
+}
+
+/*
+ * Create an authorisation token for /sbin/request-key or whoever to gain
+ * access to the caller's security data.
+ */
+struct key *request_key_auth_new(struct key *target, const void *callout_info,
+ size_t callout_len, struct key *dest_keyring)
+{
+ struct request_key_auth *rka, *irka;
+ const struct cred *cred = current->cred;
+ struct key *authkey = NULL;
+ char desc[20];
+ int ret;
+
+ kenter("%d,", target->serial);
+
+ /* allocate a auth record */
+ rka = kmalloc(sizeof(*rka), GFP_KERNEL);
+ if (!rka) {
+ kleave(" = -ENOMEM");
+ return ERR_PTR(-ENOMEM);
+ }
+ rka->callout_info = kmalloc(callout_len, GFP_KERNEL);
+ if (!rka->callout_info) {
+ kleave(" = -ENOMEM");
+ kfree(rka);
+ return ERR_PTR(-ENOMEM);
+ }
+
+ /* see if the calling process is already servicing the key request of
+ * another process */
+ if (cred->request_key_auth) {
+ /* it is - use that instantiation context here too */
+ down_read(&cred->request_key_auth->sem);
+
+ /* if the auth key has been revoked, then the key we're
+ * servicing is already instantiated */
+ if (test_bit(KEY_FLAG_REVOKED, &cred->request_key_auth->flags))
+ goto auth_key_revoked;
+
+ irka = cred->request_key_auth->payload.data;
+ rka->cred = get_cred(irka->cred);
+ rka->pid = irka->pid;
+
+ up_read(&cred->request_key_auth->sem);
+ }
+ else {
+ /* it isn't - use this process as the context */
+ rka->cred = get_cred(cred);
+ rka->pid = current->pid;
+ }
+
+ rka->target_key = key_get(target);
+ rka->dest_keyring = key_get(dest_keyring);
+ memcpy(rka->callout_info, callout_info, callout_len);
+ rka->callout_len = callout_len;
+
+ /* allocate the auth key */
+ sprintf(desc, "%x", target->serial);
+
+ authkey = key_alloc(&key_type_request_key_auth, desc,
+ cred->fsuid, cred->fsgid, cred,
+ KEY_POS_VIEW | KEY_POS_READ | KEY_POS_SEARCH |
+ KEY_USR_VIEW, KEY_ALLOC_NOT_IN_QUOTA);
+ if (IS_ERR(authkey)) {
+ ret = PTR_ERR(authkey);
+ goto error_alloc;
+ }
+
+ /* construct the auth key */
+ ret = key_instantiate_and_link(authkey, rka, 0, NULL, NULL);
+ if (ret < 0)
+ goto error_inst;
+
+ kleave(" = {%d,%d}", authkey->serial, atomic_read(&authkey->usage));
+ return authkey;
+
+auth_key_revoked:
+ up_read(&cred->request_key_auth->sem);
+ kfree(rka->callout_info);
+ kfree(rka);
+ kleave("= -EKEYREVOKED");
+ return ERR_PTR(-EKEYREVOKED);
+
+error_inst:
+ key_revoke(authkey);
+ key_put(authkey);
+error_alloc:
+ key_put(rka->target_key);
+ key_put(rka->dest_keyring);
+ kfree(rka->callout_info);
+ kfree(rka);
+ kleave("= %d", ret);
+ return ERR_PTR(ret);
+}
+
+/*
+ * See if an authorisation key is associated with a particular key.
+ */
+static int key_get_instantiation_authkey_match(const struct key *key,
+ const void *_id)
+{
+ struct request_key_auth *rka = key->payload.data;
+ key_serial_t id = (key_serial_t)(unsigned long) _id;
+
+ return rka->target_key->serial == id;
+}
+
+/*
+ * Search the current process's keyrings for the authorisation key for
+ * instantiation of a key.
+ */
+struct key *key_get_instantiation_authkey(key_serial_t target_id)
+{
+ const struct cred *cred = current_cred();
+ struct key *authkey;
+ key_ref_t authkey_ref;
+
+ authkey_ref = search_process_keyrings(
+ &key_type_request_key_auth,
+ (void *) (unsigned long) target_id,
+ key_get_instantiation_authkey_match,
+ cred);
+
+ if (IS_ERR(authkey_ref)) {
+ authkey = ERR_CAST(authkey_ref);
+ goto error;
+ }
+
+ authkey = key_ref_to_ptr(authkey_ref);
+ if (test_bit(KEY_FLAG_REVOKED, &authkey->flags)) {
+ key_put(authkey);
+ authkey = ERR_PTR(-EKEYREVOKED);
+ }
+
+error:
+ return authkey;
+}
diff --git a/security/keys/sysctl.c b/security/keys/sysctl.c
new file mode 100644
index 00000000..ee32d181
--- /dev/null
+++ b/security/keys/sysctl.c
@@ -0,0 +1,65 @@
+/* Key management controls
+ *
+ * Copyright (C) 2008 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public Licence
+ * as published by the Free Software Foundation; either version
+ * 2 of the Licence, or (at your option) any later version.
+ */
+
+#include <linux/key.h>
+#include <linux/sysctl.h>
+#include "internal.h"
+
+static const int zero, one = 1, max = INT_MAX;
+
+ctl_table key_sysctls[] = {
+ {
+ .procname = "maxkeys",
+ .data = &key_quota_maxkeys,
+ .maxlen = sizeof(unsigned),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = (void *) &one,
+ .extra2 = (void *) &max,
+ },
+ {
+ .procname = "maxbytes",
+ .data = &key_quota_maxbytes,
+ .maxlen = sizeof(unsigned),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = (void *) &one,
+ .extra2 = (void *) &max,
+ },
+ {
+ .procname = "root_maxkeys",
+ .data = &key_quota_root_maxkeys,
+ .maxlen = sizeof(unsigned),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = (void *) &one,
+ .extra2 = (void *) &max,
+ },
+ {
+ .procname = "root_maxbytes",
+ .data = &key_quota_root_maxbytes,
+ .maxlen = sizeof(unsigned),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = (void *) &one,
+ .extra2 = (void *) &max,
+ },
+ {
+ .procname = "gc_delay",
+ .data = &key_gc_delay,
+ .maxlen = sizeof(unsigned),
+ .mode = 0644,
+ .proc_handler = proc_dointvec_minmax,
+ .extra1 = (void *) &zero,
+ .extra2 = (void *) &max,
+ },
+ { }
+};
diff --git a/security/keys/trusted.c b/security/keys/trusted.c
new file mode 100644
index 00000000..0c33e2ea
--- /dev/null
+++ b/security/keys/trusted.c
@@ -0,0 +1,1180 @@
+/*
+ * Copyright (C) 2010 IBM Corporation
+ *
+ * Author:
+ * David Safford <safford@us.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, version 2 of the License.
+ *
+ * See Documentation/security/keys-trusted-encrypted.txt
+ */
+
+#include <linux/uaccess.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/parser.h>
+#include <linux/string.h>
+#include <linux/err.h>
+#include <keys/user-type.h>
+#include <keys/trusted-type.h>
+#include <linux/key-type.h>
+#include <linux/rcupdate.h>
+#include <linux/crypto.h>
+#include <crypto/hash.h>
+#include <crypto/sha.h>
+#include <linux/capability.h>
+#include <linux/tpm.h>
+#include <linux/tpm_command.h>
+
+#include "trusted.h"
+
+static const char hmac_alg[] = "hmac(sha1)";
+static const char hash_alg[] = "sha1";
+
+struct sdesc {
+ struct shash_desc shash;
+ char ctx[];
+};
+
+static struct crypto_shash *hashalg;
+static struct crypto_shash *hmacalg;
+
+static struct sdesc *init_sdesc(struct crypto_shash *alg)
+{
+ struct sdesc *sdesc;
+ int size;
+
+ size = sizeof(struct shash_desc) + crypto_shash_descsize(alg);
+ sdesc = kmalloc(size, GFP_KERNEL);
+ if (!sdesc)
+ return ERR_PTR(-ENOMEM);
+ sdesc->shash.tfm = alg;
+ sdesc->shash.flags = 0x0;
+ return sdesc;
+}
+
+static int TSS_sha1(const unsigned char *data, unsigned int datalen,
+ unsigned char *digest)
+{
+ struct sdesc *sdesc;
+ int ret;
+
+ sdesc = init_sdesc(hashalg);
+ if (IS_ERR(sdesc)) {
+ pr_info("trusted_key: can't alloc %s\n", hash_alg);
+ return PTR_ERR(sdesc);
+ }
+
+ ret = crypto_shash_digest(&sdesc->shash, data, datalen, digest);
+ kfree(sdesc);
+ return ret;
+}
+
+static int TSS_rawhmac(unsigned char *digest, const unsigned char *key,
+ unsigned int keylen, ...)
+{
+ struct sdesc *sdesc;
+ va_list argp;
+ unsigned int dlen;
+ unsigned char *data;
+ int ret;
+
+ sdesc = init_sdesc(hmacalg);
+ if (IS_ERR(sdesc)) {
+ pr_info("trusted_key: can't alloc %s\n", hmac_alg);
+ return PTR_ERR(sdesc);
+ }
+
+ ret = crypto_shash_setkey(hmacalg, key, keylen);
+ if (ret < 0)
+ goto out;
+ ret = crypto_shash_init(&sdesc->shash);
+ if (ret < 0)
+ goto out;
+
+ va_start(argp, keylen);
+ for (;;) {
+ dlen = va_arg(argp, unsigned int);
+ if (dlen == 0)
+ break;
+ data = va_arg(argp, unsigned char *);
+ if (data == NULL) {
+ ret = -EINVAL;
+ break;
+ }
+ ret = crypto_shash_update(&sdesc->shash, data, dlen);
+ if (ret < 0)
+ break;
+ }
+ va_end(argp);
+ if (!ret)
+ ret = crypto_shash_final(&sdesc->shash, digest);
+out:
+ kfree(sdesc);
+ return ret;
+}
+
+/*
+ * calculate authorization info fields to send to TPM
+ */
+static int TSS_authhmac(unsigned char *digest, const unsigned char *key,
+ unsigned int keylen, unsigned char *h1,
+ unsigned char *h2, unsigned char h3, ...)
+{
+ unsigned char paramdigest[SHA1_DIGEST_SIZE];
+ struct sdesc *sdesc;
+ unsigned int dlen;
+ unsigned char *data;
+ unsigned char c;
+ int ret;
+ va_list argp;
+
+ sdesc = init_sdesc(hashalg);
+ if (IS_ERR(sdesc)) {
+ pr_info("trusted_key: can't alloc %s\n", hash_alg);
+ return PTR_ERR(sdesc);
+ }
+
+ c = h3;
+ ret = crypto_shash_init(&sdesc->shash);
+ if (ret < 0)
+ goto out;
+ va_start(argp, h3);
+ for (;;) {
+ dlen = va_arg(argp, unsigned int);
+ if (dlen == 0)
+ break;
+ data = va_arg(argp, unsigned char *);
+ if (!data) {
+ ret = -EINVAL;
+ break;
+ }
+ ret = crypto_shash_update(&sdesc->shash, data, dlen);
+ if (ret < 0)
+ break;
+ }
+ va_end(argp);
+ if (!ret)
+ ret = crypto_shash_final(&sdesc->shash, paramdigest);
+ if (!ret)
+ ret = TSS_rawhmac(digest, key, keylen, SHA1_DIGEST_SIZE,
+ paramdigest, TPM_NONCE_SIZE, h1,
+ TPM_NONCE_SIZE, h2, 1, &c, 0, 0);
+out:
+ kfree(sdesc);
+ return ret;
+}
+
+/*
+ * verify the AUTH1_COMMAND (Seal) result from TPM
+ */
+static int TSS_checkhmac1(unsigned char *buffer,
+ const uint32_t command,
+ const unsigned char *ononce,
+ const unsigned char *key,
+ unsigned int keylen, ...)
+{
+ uint32_t bufsize;
+ uint16_t tag;
+ uint32_t ordinal;
+ uint32_t result;
+ unsigned char *enonce;
+ unsigned char *continueflag;
+ unsigned char *authdata;
+ unsigned char testhmac[SHA1_DIGEST_SIZE];
+ unsigned char paramdigest[SHA1_DIGEST_SIZE];
+ struct sdesc *sdesc;
+ unsigned int dlen;
+ unsigned int dpos;
+ va_list argp;
+ int ret;
+
+ bufsize = LOAD32(buffer, TPM_SIZE_OFFSET);
+ tag = LOAD16(buffer, 0);
+ ordinal = command;
+ result = LOAD32N(buffer, TPM_RETURN_OFFSET);
+ if (tag == TPM_TAG_RSP_COMMAND)
+ return 0;
+ if (tag != TPM_TAG_RSP_AUTH1_COMMAND)
+ return -EINVAL;
+ authdata = buffer + bufsize - SHA1_DIGEST_SIZE;
+ continueflag = authdata - 1;
+ enonce = continueflag - TPM_NONCE_SIZE;
+
+ sdesc = init_sdesc(hashalg);
+ if (IS_ERR(sdesc)) {
+ pr_info("trusted_key: can't alloc %s\n", hash_alg);
+ return PTR_ERR(sdesc);
+ }
+ ret = crypto_shash_init(&sdesc->shash);
+ if (ret < 0)
+ goto out;
+ ret = crypto_shash_update(&sdesc->shash, (const u8 *)&result,
+ sizeof result);
+ if (ret < 0)
+ goto out;
+ ret = crypto_shash_update(&sdesc->shash, (const u8 *)&ordinal,
+ sizeof ordinal);
+ if (ret < 0)
+ goto out;
+ va_start(argp, keylen);
+ for (;;) {
+ dlen = va_arg(argp, unsigned int);
+ if (dlen == 0)
+ break;
+ dpos = va_arg(argp, unsigned int);
+ ret = crypto_shash_update(&sdesc->shash, buffer + dpos, dlen);
+ if (ret < 0)
+ break;
+ }
+ va_end(argp);
+ if (!ret)
+ ret = crypto_shash_final(&sdesc->shash, paramdigest);
+ if (ret < 0)
+ goto out;
+
+ ret = TSS_rawhmac(testhmac, key, keylen, SHA1_DIGEST_SIZE, paramdigest,
+ TPM_NONCE_SIZE, enonce, TPM_NONCE_SIZE, ononce,
+ 1, continueflag, 0, 0);
+ if (ret < 0)
+ goto out;
+
+ if (memcmp(testhmac, authdata, SHA1_DIGEST_SIZE))
+ ret = -EINVAL;
+out:
+ kfree(sdesc);
+ return ret;
+}
+
+/*
+ * verify the AUTH2_COMMAND (unseal) result from TPM
+ */
+static int TSS_checkhmac2(unsigned char *buffer,
+ const uint32_t command,
+ const unsigned char *ononce,
+ const unsigned char *key1,
+ unsigned int keylen1,
+ const unsigned char *key2,
+ unsigned int keylen2, ...)
+{
+ uint32_t bufsize;
+ uint16_t tag;
+ uint32_t ordinal;
+ uint32_t result;
+ unsigned char *enonce1;
+ unsigned char *continueflag1;
+ unsigned char *authdata1;
+ unsigned char *enonce2;
+ unsigned char *continueflag2;
+ unsigned char *authdata2;
+ unsigned char testhmac1[SHA1_DIGEST_SIZE];
+ unsigned char testhmac2[SHA1_DIGEST_SIZE];
+ unsigned char paramdigest[SHA1_DIGEST_SIZE];
+ struct sdesc *sdesc;
+ unsigned int dlen;
+ unsigned int dpos;
+ va_list argp;
+ int ret;
+
+ bufsize = LOAD32(buffer, TPM_SIZE_OFFSET);
+ tag = LOAD16(buffer, 0);
+ ordinal = command;
+ result = LOAD32N(buffer, TPM_RETURN_OFFSET);
+
+ if (tag == TPM_TAG_RSP_COMMAND)
+ return 0;
+ if (tag != TPM_TAG_RSP_AUTH2_COMMAND)
+ return -EINVAL;
+ authdata1 = buffer + bufsize - (SHA1_DIGEST_SIZE + 1
+ + SHA1_DIGEST_SIZE + SHA1_DIGEST_SIZE);
+ authdata2 = buffer + bufsize - (SHA1_DIGEST_SIZE);
+ continueflag1 = authdata1 - 1;
+ continueflag2 = authdata2 - 1;
+ enonce1 = continueflag1 - TPM_NONCE_SIZE;
+ enonce2 = continueflag2 - TPM_NONCE_SIZE;
+
+ sdesc = init_sdesc(hashalg);
+ if (IS_ERR(sdesc)) {
+ pr_info("trusted_key: can't alloc %s\n", hash_alg);
+ return PTR_ERR(sdesc);
+ }
+ ret = crypto_shash_init(&sdesc->shash);
+ if (ret < 0)
+ goto out;
+ ret = crypto_shash_update(&sdesc->shash, (const u8 *)&result,
+ sizeof result);
+ if (ret < 0)
+ goto out;
+ ret = crypto_shash_update(&sdesc->shash, (const u8 *)&ordinal,
+ sizeof ordinal);
+ if (ret < 0)
+ goto out;
+
+ va_start(argp, keylen2);
+ for (;;) {
+ dlen = va_arg(argp, unsigned int);
+ if (dlen == 0)
+ break;
+ dpos = va_arg(argp, unsigned int);
+ ret = crypto_shash_update(&sdesc->shash, buffer + dpos, dlen);
+ if (ret < 0)
+ break;
+ }
+ va_end(argp);
+ if (!ret)
+ ret = crypto_shash_final(&sdesc->shash, paramdigest);
+ if (ret < 0)
+ goto out;
+
+ ret = TSS_rawhmac(testhmac1, key1, keylen1, SHA1_DIGEST_SIZE,
+ paramdigest, TPM_NONCE_SIZE, enonce1,
+ TPM_NONCE_SIZE, ononce, 1, continueflag1, 0, 0);
+ if (ret < 0)
+ goto out;
+ if (memcmp(testhmac1, authdata1, SHA1_DIGEST_SIZE)) {
+ ret = -EINVAL;
+ goto out;
+ }
+ ret = TSS_rawhmac(testhmac2, key2, keylen2, SHA1_DIGEST_SIZE,
+ paramdigest, TPM_NONCE_SIZE, enonce2,
+ TPM_NONCE_SIZE, ononce, 1, continueflag2, 0, 0);
+ if (ret < 0)
+ goto out;
+ if (memcmp(testhmac2, authdata2, SHA1_DIGEST_SIZE))
+ ret = -EINVAL;
+out:
+ kfree(sdesc);
+ return ret;
+}
+
+/*
+ * For key specific tpm requests, we will generate and send our
+ * own TPM command packets using the drivers send function.
+ */
+static int trusted_tpm_send(const u32 chip_num, unsigned char *cmd,
+ size_t buflen)
+{
+ int rc;
+
+ dump_tpm_buf(cmd);
+ rc = tpm_send(chip_num, cmd, buflen);
+ dump_tpm_buf(cmd);
+ if (rc > 0)
+ /* Can't return positive return codes values to keyctl */
+ rc = -EPERM;
+ return rc;
+}
+
+/*
+ * get a random value from TPM
+ */
+static int tpm_get_random(struct tpm_buf *tb, unsigned char *buf, uint32_t len)
+{
+ int ret;
+
+ INIT_BUF(tb);
+ store16(tb, TPM_TAG_RQU_COMMAND);
+ store32(tb, TPM_GETRANDOM_SIZE);
+ store32(tb, TPM_ORD_GETRANDOM);
+ store32(tb, len);
+ ret = trusted_tpm_send(TPM_ANY_NUM, tb->data, sizeof tb->data);
+ if (!ret)
+ memcpy(buf, tb->data + TPM_GETRANDOM_SIZE, len);
+ return ret;
+}
+
+static int my_get_random(unsigned char *buf, int len)
+{
+ struct tpm_buf *tb;
+ int ret;
+
+ tb = kmalloc(sizeof *tb, GFP_KERNEL);
+ if (!tb)
+ return -ENOMEM;
+ ret = tpm_get_random(tb, buf, len);
+
+ kfree(tb);
+ return ret;
+}
+
+/*
+ * Lock a trusted key, by extending a selected PCR.
+ *
+ * Prevents a trusted key that is sealed to PCRs from being accessed.
+ * This uses the tpm driver's extend function.
+ */
+static int pcrlock(const int pcrnum)
+{
+ unsigned char hash[SHA1_DIGEST_SIZE];
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ ret = my_get_random(hash, SHA1_DIGEST_SIZE);
+ if (ret < 0)
+ return ret;
+ return tpm_pcr_extend(TPM_ANY_NUM, pcrnum, hash) ? -EINVAL : 0;
+}
+
+/*
+ * Create an object specific authorisation protocol (OSAP) session
+ */
+static int osap(struct tpm_buf *tb, struct osapsess *s,
+ const unsigned char *key, uint16_t type, uint32_t handle)
+{
+ unsigned char enonce[TPM_NONCE_SIZE];
+ unsigned char ononce[TPM_NONCE_SIZE];
+ int ret;
+
+ ret = tpm_get_random(tb, ononce, TPM_NONCE_SIZE);
+ if (ret < 0)
+ return ret;
+
+ INIT_BUF(tb);
+ store16(tb, TPM_TAG_RQU_COMMAND);
+ store32(tb, TPM_OSAP_SIZE);
+ store32(tb, TPM_ORD_OSAP);
+ store16(tb, type);
+ store32(tb, handle);
+ storebytes(tb, ononce, TPM_NONCE_SIZE);
+
+ ret = trusted_tpm_send(TPM_ANY_NUM, tb->data, MAX_BUF_SIZE);
+ if (ret < 0)
+ return ret;
+
+ s->handle = LOAD32(tb->data, TPM_DATA_OFFSET);
+ memcpy(s->enonce, &(tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)]),
+ TPM_NONCE_SIZE);
+ memcpy(enonce, &(tb->data[TPM_DATA_OFFSET + sizeof(uint32_t) +
+ TPM_NONCE_SIZE]), TPM_NONCE_SIZE);
+ return TSS_rawhmac(s->secret, key, SHA1_DIGEST_SIZE, TPM_NONCE_SIZE,
+ enonce, TPM_NONCE_SIZE, ononce, 0, 0);
+}
+
+/*
+ * Create an object independent authorisation protocol (oiap) session
+ */
+static int oiap(struct tpm_buf *tb, uint32_t *handle, unsigned char *nonce)
+{
+ int ret;
+
+ INIT_BUF(tb);
+ store16(tb, TPM_TAG_RQU_COMMAND);
+ store32(tb, TPM_OIAP_SIZE);
+ store32(tb, TPM_ORD_OIAP);
+ ret = trusted_tpm_send(TPM_ANY_NUM, tb->data, MAX_BUF_SIZE);
+ if (ret < 0)
+ return ret;
+
+ *handle = LOAD32(tb->data, TPM_DATA_OFFSET);
+ memcpy(nonce, &tb->data[TPM_DATA_OFFSET + sizeof(uint32_t)],
+ TPM_NONCE_SIZE);
+ return 0;
+}
+
+struct tpm_digests {
+ unsigned char encauth[SHA1_DIGEST_SIZE];
+ unsigned char pubauth[SHA1_DIGEST_SIZE];
+ unsigned char xorwork[SHA1_DIGEST_SIZE * 2];
+ unsigned char xorhash[SHA1_DIGEST_SIZE];
+ unsigned char nonceodd[TPM_NONCE_SIZE];
+};
+
+/*
+ * Have the TPM seal(encrypt) the trusted key, possibly based on
+ * Platform Configuration Registers (PCRs). AUTH1 for sealing key.
+ */
+static int tpm_seal(struct tpm_buf *tb, uint16_t keytype,
+ uint32_t keyhandle, const unsigned char *keyauth,
+ const unsigned char *data, uint32_t datalen,
+ unsigned char *blob, uint32_t *bloblen,
+ const unsigned char *blobauth,
+ const unsigned char *pcrinfo, uint32_t pcrinfosize)
+{
+ struct osapsess sess;
+ struct tpm_digests *td;
+ unsigned char cont;
+ uint32_t ordinal;
+ uint32_t pcrsize;
+ uint32_t datsize;
+ int sealinfosize;
+ int encdatasize;
+ int storedsize;
+ int ret;
+ int i;
+
+ /* alloc some work space for all the hashes */
+ td = kmalloc(sizeof *td, GFP_KERNEL);
+ if (!td)
+ return -ENOMEM;
+
+ /* get session for sealing key */
+ ret = osap(tb, &sess, keyauth, keytype, keyhandle);
+ if (ret < 0)
+ goto out;
+ dump_sess(&sess);
+
+ /* calculate encrypted authorization value */
+ memcpy(td->xorwork, sess.secret, SHA1_DIGEST_SIZE);
+ memcpy(td->xorwork + SHA1_DIGEST_SIZE, sess.enonce, SHA1_DIGEST_SIZE);
+ ret = TSS_sha1(td->xorwork, SHA1_DIGEST_SIZE * 2, td->xorhash);
+ if (ret < 0)
+ goto out;
+
+ ret = tpm_get_random(tb, td->nonceodd, TPM_NONCE_SIZE);
+ if (ret < 0)
+ goto out;
+ ordinal = htonl(TPM_ORD_SEAL);
+ datsize = htonl(datalen);
+ pcrsize = htonl(pcrinfosize);
+ cont = 0;
+
+ /* encrypt data authorization key */
+ for (i = 0; i < SHA1_DIGEST_SIZE; ++i)
+ td->encauth[i] = td->xorhash[i] ^ blobauth[i];
+
+ /* calculate authorization HMAC value */
+ if (pcrinfosize == 0) {
+ /* no pcr info specified */
+ ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
+ sess.enonce, td->nonceodd, cont,
+ sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
+ td->encauth, sizeof(uint32_t), &pcrsize,
+ sizeof(uint32_t), &datsize, datalen, data, 0,
+ 0);
+ } else {
+ /* pcr info specified */
+ ret = TSS_authhmac(td->pubauth, sess.secret, SHA1_DIGEST_SIZE,
+ sess.enonce, td->nonceodd, cont,
+ sizeof(uint32_t), &ordinal, SHA1_DIGEST_SIZE,
+ td->encauth, sizeof(uint32_t), &pcrsize,
+ pcrinfosize, pcrinfo, sizeof(uint32_t),
+ &datsize, datalen, data, 0, 0);
+ }
+ if (ret < 0)
+ goto out;
+
+ /* build and send the TPM request packet */
+ INIT_BUF(tb);
+ store16(tb, TPM_TAG_RQU_AUTH1_COMMAND);
+ store32(tb, TPM_SEAL_SIZE + pcrinfosize + datalen);
+ store32(tb, TPM_ORD_SEAL);
+ store32(tb, keyhandle);
+ storebytes(tb, td->encauth, SHA1_DIGEST_SIZE);
+ store32(tb, pcrinfosize);
+ storebytes(tb, pcrinfo, pcrinfosize);
+ store32(tb, datalen);
+ storebytes(tb, data, datalen);
+ store32(tb, sess.handle);
+ storebytes(tb, td->nonceodd, TPM_NONCE_SIZE);
+ store8(tb, cont);
+ storebytes(tb, td->pubauth, SHA1_DIGEST_SIZE);
+
+ ret = trusted_tpm_send(TPM_ANY_NUM, tb->data, MAX_BUF_SIZE);
+ if (ret < 0)
+ goto out;
+
+ /* calculate the size of the returned Blob */
+ sealinfosize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t));
+ encdatasize = LOAD32(tb->data, TPM_DATA_OFFSET + sizeof(uint32_t) +
+ sizeof(uint32_t) + sealinfosize);
+ storedsize = sizeof(uint32_t) + sizeof(uint32_t) + sealinfosize +
+ sizeof(uint32_t) + encdatasize;
+
+ /* check the HMAC in the response */
+ ret = TSS_checkhmac1(tb->data, ordinal, td->nonceodd, sess.secret,
+ SHA1_DIGEST_SIZE, storedsize, TPM_DATA_OFFSET, 0,
+ 0);
+
+ /* copy the returned blob to caller */
+ if (!ret) {
+ memcpy(blob, tb->data + TPM_DATA_OFFSET, storedsize);
+ *bloblen = storedsize;
+ }
+out:
+ kfree(td);
+ return ret;
+}
+
+/*
+ * use the AUTH2_COMMAND form of unseal, to authorize both key and blob
+ */
+static int tpm_unseal(struct tpm_buf *tb,
+ uint32_t keyhandle, const unsigned char *keyauth,
+ const unsigned char *blob, int bloblen,
+ const unsigned char *blobauth,
+ unsigned char *data, unsigned int *datalen)
+{
+ unsigned char nonceodd[TPM_NONCE_SIZE];
+ unsigned char enonce1[TPM_NONCE_SIZE];
+ unsigned char enonce2[TPM_NONCE_SIZE];
+ unsigned char authdata1[SHA1_DIGEST_SIZE];
+ unsigned char authdata2[SHA1_DIGEST_SIZE];
+ uint32_t authhandle1 = 0;
+ uint32_t authhandle2 = 0;
+ unsigned char cont = 0;
+ uint32_t ordinal;
+ uint32_t keyhndl;
+ int ret;
+
+ /* sessions for unsealing key and data */
+ ret = oiap(tb, &authhandle1, enonce1);
+ if (ret < 0) {
+ pr_info("trusted_key: oiap failed (%d)\n", ret);
+ return ret;
+ }
+ ret = oiap(tb, &authhandle2, enonce2);
+ if (ret < 0) {
+ pr_info("trusted_key: oiap failed (%d)\n", ret);
+ return ret;
+ }
+
+ ordinal = htonl(TPM_ORD_UNSEAL);
+ keyhndl = htonl(SRKHANDLE);
+ ret = tpm_get_random(tb, nonceodd, TPM_NONCE_SIZE);
+ if (ret < 0) {
+ pr_info("trusted_key: tpm_get_random failed (%d)\n", ret);
+ return ret;
+ }
+ ret = TSS_authhmac(authdata1, keyauth, TPM_NONCE_SIZE,
+ enonce1, nonceodd, cont, sizeof(uint32_t),
+ &ordinal, bloblen, blob, 0, 0);
+ if (ret < 0)
+ return ret;
+ ret = TSS_authhmac(authdata2, blobauth, TPM_NONCE_SIZE,
+ enonce2, nonceodd, cont, sizeof(uint32_t),
+ &ordinal, bloblen, blob, 0, 0);
+ if (ret < 0)
+ return ret;
+
+ /* build and send TPM request packet */
+ INIT_BUF(tb);
+ store16(tb, TPM_TAG_RQU_AUTH2_COMMAND);
+ store32(tb, TPM_UNSEAL_SIZE + bloblen);
+ store32(tb, TPM_ORD_UNSEAL);
+ store32(tb, keyhandle);
+ storebytes(tb, blob, bloblen);
+ store32(tb, authhandle1);
+ storebytes(tb, nonceodd, TPM_NONCE_SIZE);
+ store8(tb, cont);
+ storebytes(tb, authdata1, SHA1_DIGEST_SIZE);
+ store32(tb, authhandle2);
+ storebytes(tb, nonceodd, TPM_NONCE_SIZE);
+ store8(tb, cont);
+ storebytes(tb, authdata2, SHA1_DIGEST_SIZE);
+
+ ret = trusted_tpm_send(TPM_ANY_NUM, tb->data, MAX_BUF_SIZE);
+ if (ret < 0) {
+ pr_info("trusted_key: authhmac failed (%d)\n", ret);
+ return ret;
+ }
+
+ *datalen = LOAD32(tb->data, TPM_DATA_OFFSET);
+ ret = TSS_checkhmac2(tb->data, ordinal, nonceodd,
+ keyauth, SHA1_DIGEST_SIZE,
+ blobauth, SHA1_DIGEST_SIZE,
+ sizeof(uint32_t), TPM_DATA_OFFSET,
+ *datalen, TPM_DATA_OFFSET + sizeof(uint32_t), 0,
+ 0);
+ if (ret < 0) {
+ pr_info("trusted_key: TSS_checkhmac2 failed (%d)\n", ret);
+ return ret;
+ }
+ memcpy(data, tb->data + TPM_DATA_OFFSET + sizeof(uint32_t), *datalen);
+ return 0;
+}
+
+/*
+ * Have the TPM seal(encrypt) the symmetric key
+ */
+static int key_seal(struct trusted_key_payload *p,
+ struct trusted_key_options *o)
+{
+ struct tpm_buf *tb;
+ int ret;
+
+ tb = kzalloc(sizeof *tb, GFP_KERNEL);
+ if (!tb)
+ return -ENOMEM;
+
+ /* include migratable flag at end of sealed key */
+ p->key[p->key_len] = p->migratable;
+
+ ret = tpm_seal(tb, o->keytype, o->keyhandle, o->keyauth,
+ p->key, p->key_len + 1, p->blob, &p->blob_len,
+ o->blobauth, o->pcrinfo, o->pcrinfo_len);
+ if (ret < 0)
+ pr_info("trusted_key: srkseal failed (%d)\n", ret);
+
+ kfree(tb);
+ return ret;
+}
+
+/*
+ * Have the TPM unseal(decrypt) the symmetric key
+ */
+static int key_unseal(struct trusted_key_payload *p,
+ struct trusted_key_options *o)
+{
+ struct tpm_buf *tb;
+ int ret;
+
+ tb = kzalloc(sizeof *tb, GFP_KERNEL);
+ if (!tb)
+ return -ENOMEM;
+
+ ret = tpm_unseal(tb, o->keyhandle, o->keyauth, p->blob, p->blob_len,
+ o->blobauth, p->key, &p->key_len);
+ if (ret < 0)
+ pr_info("trusted_key: srkunseal failed (%d)\n", ret);
+ else
+ /* pull migratable flag out of sealed key */
+ p->migratable = p->key[--p->key_len];
+
+ kfree(tb);
+ return ret;
+}
+
+enum {
+ Opt_err = -1,
+ Opt_new, Opt_load, Opt_update,
+ Opt_keyhandle, Opt_keyauth, Opt_blobauth,
+ Opt_pcrinfo, Opt_pcrlock, Opt_migratable
+};
+
+static const match_table_t key_tokens = {
+ {Opt_new, "new"},
+ {Opt_load, "load"},
+ {Opt_update, "update"},
+ {Opt_keyhandle, "keyhandle=%s"},
+ {Opt_keyauth, "keyauth=%s"},
+ {Opt_blobauth, "blobauth=%s"},
+ {Opt_pcrinfo, "pcrinfo=%s"},
+ {Opt_pcrlock, "pcrlock=%s"},
+ {Opt_migratable, "migratable=%s"},
+ {Opt_err, NULL}
+};
+
+/* can have zero or more token= options */
+static int getoptions(char *c, struct trusted_key_payload *pay,
+ struct trusted_key_options *opt)
+{
+ substring_t args[MAX_OPT_ARGS];
+ char *p = c;
+ int token;
+ int res;
+ unsigned long handle;
+ unsigned long lock;
+
+ while ((p = strsep(&c, " \t"))) {
+ if (*p == '\0' || *p == ' ' || *p == '\t')
+ continue;
+ token = match_token(p, key_tokens, args);
+
+ switch (token) {
+ case Opt_pcrinfo:
+ opt->pcrinfo_len = strlen(args[0].from) / 2;
+ if (opt->pcrinfo_len > MAX_PCRINFO_SIZE)
+ return -EINVAL;
+ hex2bin(opt->pcrinfo, args[0].from, opt->pcrinfo_len);
+ break;
+ case Opt_keyhandle:
+ res = strict_strtoul(args[0].from, 16, &handle);
+ if (res < 0)
+ return -EINVAL;
+ opt->keytype = SEAL_keytype;
+ opt->keyhandle = handle;
+ break;
+ case Opt_keyauth:
+ if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
+ return -EINVAL;
+ hex2bin(opt->keyauth, args[0].from, SHA1_DIGEST_SIZE);
+ break;
+ case Opt_blobauth:
+ if (strlen(args[0].from) != 2 * SHA1_DIGEST_SIZE)
+ return -EINVAL;
+ hex2bin(opt->blobauth, args[0].from, SHA1_DIGEST_SIZE);
+ break;
+ case Opt_migratable:
+ if (*args[0].from == '0')
+ pay->migratable = 0;
+ else
+ return -EINVAL;
+ break;
+ case Opt_pcrlock:
+ res = strict_strtoul(args[0].from, 10, &lock);
+ if (res < 0)
+ return -EINVAL;
+ opt->pcrlock = lock;
+ break;
+ default:
+ return -EINVAL;
+ }
+ }
+ return 0;
+}
+
+/*
+ * datablob_parse - parse the keyctl data and fill in the
+ * payload and options structures
+ *
+ * On success returns 0, otherwise -EINVAL.
+ */
+static int datablob_parse(char *datablob, struct trusted_key_payload *p,
+ struct trusted_key_options *o)
+{
+ substring_t args[MAX_OPT_ARGS];
+ long keylen;
+ int ret = -EINVAL;
+ int key_cmd;
+ char *c;
+
+ /* main command */
+ c = strsep(&datablob, " \t");
+ if (!c)
+ return -EINVAL;
+ key_cmd = match_token(c, key_tokens, args);
+ switch (key_cmd) {
+ case Opt_new:
+ /* first argument is key size */
+ c = strsep(&datablob, " \t");
+ if (!c)
+ return -EINVAL;
+ ret = strict_strtol(c, 10, &keylen);
+ if (ret < 0 || keylen < MIN_KEY_SIZE || keylen > MAX_KEY_SIZE)
+ return -EINVAL;
+ p->key_len = keylen;
+ ret = getoptions(datablob, p, o);
+ if (ret < 0)
+ return ret;
+ ret = Opt_new;
+ break;
+ case Opt_load:
+ /* first argument is sealed blob */
+ c = strsep(&datablob, " \t");
+ if (!c)
+ return -EINVAL;
+ p->blob_len = strlen(c) / 2;
+ if (p->blob_len > MAX_BLOB_SIZE)
+ return -EINVAL;
+ hex2bin(p->blob, c, p->blob_len);
+ ret = getoptions(datablob, p, o);
+ if (ret < 0)
+ return ret;
+ ret = Opt_load;
+ break;
+ case Opt_update:
+ /* all arguments are options */
+ ret = getoptions(datablob, p, o);
+ if (ret < 0)
+ return ret;
+ ret = Opt_update;
+ break;
+ case Opt_err:
+ return -EINVAL;
+ break;
+ }
+ return ret;
+}
+
+static struct trusted_key_options *trusted_options_alloc(void)
+{
+ struct trusted_key_options *options;
+
+ options = kzalloc(sizeof *options, GFP_KERNEL);
+ if (options) {
+ /* set any non-zero defaults */
+ options->keytype = SRK_keytype;
+ options->keyhandle = SRKHANDLE;
+ }
+ return options;
+}
+
+static struct trusted_key_payload *trusted_payload_alloc(struct key *key)
+{
+ struct trusted_key_payload *p = NULL;
+ int ret;
+
+ ret = key_payload_reserve(key, sizeof *p);
+ if (ret < 0)
+ return p;
+ p = kzalloc(sizeof *p, GFP_KERNEL);
+ if (p)
+ p->migratable = 1; /* migratable by default */
+ return p;
+}
+
+/*
+ * trusted_instantiate - create a new trusted key
+ *
+ * Unseal an existing trusted blob or, for a new key, get a
+ * random key, then seal and create a trusted key-type key,
+ * adding it to the specified keyring.
+ *
+ * On success, return 0. Otherwise return errno.
+ */
+static int trusted_instantiate(struct key *key, const void *data,
+ size_t datalen)
+{
+ struct trusted_key_payload *payload = NULL;
+ struct trusted_key_options *options = NULL;
+ char *datablob;
+ int ret = 0;
+ int key_cmd;
+
+ if (datalen <= 0 || datalen > 32767 || !data)
+ return -EINVAL;
+
+ datablob = kmalloc(datalen + 1, GFP_KERNEL);
+ if (!datablob)
+ return -ENOMEM;
+ memcpy(datablob, data, datalen);
+ datablob[datalen] = '\0';
+
+ options = trusted_options_alloc();
+ if (!options) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ payload = trusted_payload_alloc(key);
+ if (!payload) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ key_cmd = datablob_parse(datablob, payload, options);
+ if (key_cmd < 0) {
+ ret = key_cmd;
+ goto out;
+ }
+
+ dump_payload(payload);
+ dump_options(options);
+
+ switch (key_cmd) {
+ case Opt_load:
+ ret = key_unseal(payload, options);
+ dump_payload(payload);
+ dump_options(options);
+ if (ret < 0)
+ pr_info("trusted_key: key_unseal failed (%d)\n", ret);
+ break;
+ case Opt_new:
+ ret = my_get_random(payload->key, payload->key_len);
+ if (ret < 0) {
+ pr_info("trusted_key: key_create failed (%d)\n", ret);
+ goto out;
+ }
+ ret = key_seal(payload, options);
+ if (ret < 0)
+ pr_info("trusted_key: key_seal failed (%d)\n", ret);
+ break;
+ default:
+ ret = -EINVAL;
+ goto out;
+ }
+ if (!ret && options->pcrlock)
+ ret = pcrlock(options->pcrlock);
+out:
+ kfree(datablob);
+ kfree(options);
+ if (!ret)
+ rcu_assign_pointer(key->payload.data, payload);
+ else
+ kfree(payload);
+ return ret;
+}
+
+static void trusted_rcu_free(struct rcu_head *rcu)
+{
+ struct trusted_key_payload *p;
+
+ p = container_of(rcu, struct trusted_key_payload, rcu);
+ memset(p->key, 0, p->key_len);
+ kfree(p);
+}
+
+/*
+ * trusted_update - reseal an existing key with new PCR values
+ */
+static int trusted_update(struct key *key, const void *data, size_t datalen)
+{
+ struct trusted_key_payload *p = key->payload.data;
+ struct trusted_key_payload *new_p;
+ struct trusted_key_options *new_o;
+ char *datablob;
+ int ret = 0;
+
+ if (!p->migratable)
+ return -EPERM;
+ if (datalen <= 0 || datalen > 32767 || !data)
+ return -EINVAL;
+
+ datablob = kmalloc(datalen + 1, GFP_KERNEL);
+ if (!datablob)
+ return -ENOMEM;
+ new_o = trusted_options_alloc();
+ if (!new_o) {
+ ret = -ENOMEM;
+ goto out;
+ }
+ new_p = trusted_payload_alloc(key);
+ if (!new_p) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ memcpy(datablob, data, datalen);
+ datablob[datalen] = '\0';
+ ret = datablob_parse(datablob, new_p, new_o);
+ if (ret != Opt_update) {
+ ret = -EINVAL;
+ kfree(new_p);
+ goto out;
+ }
+ /* copy old key values, and reseal with new pcrs */
+ new_p->migratable = p->migratable;
+ new_p->key_len = p->key_len;
+ memcpy(new_p->key, p->key, p->key_len);
+ dump_payload(p);
+ dump_payload(new_p);
+
+ ret = key_seal(new_p, new_o);
+ if (ret < 0) {
+ pr_info("trusted_key: key_seal failed (%d)\n", ret);
+ kfree(new_p);
+ goto out;
+ }
+ if (new_o->pcrlock) {
+ ret = pcrlock(new_o->pcrlock);
+ if (ret < 0) {
+ pr_info("trusted_key: pcrlock failed (%d)\n", ret);
+ kfree(new_p);
+ goto out;
+ }
+ }
+ rcu_assign_pointer(key->payload.data, new_p);
+ call_rcu(&p->rcu, trusted_rcu_free);
+out:
+ kfree(datablob);
+ kfree(new_o);
+ return ret;
+}
+
+/*
+ * trusted_read - copy the sealed blob data to userspace in hex.
+ * On success, return to userspace the trusted key datablob size.
+ */
+static long trusted_read(const struct key *key, char __user *buffer,
+ size_t buflen)
+{
+ struct trusted_key_payload *p;
+ char *ascii_buf;
+ char *bufp;
+ int i;
+
+ p = rcu_dereference_key(key);
+ if (!p)
+ return -EINVAL;
+ if (!buffer || buflen <= 0)
+ return 2 * p->blob_len;
+ ascii_buf = kmalloc(2 * p->blob_len, GFP_KERNEL);
+ if (!ascii_buf)
+ return -ENOMEM;
+
+ bufp = ascii_buf;
+ for (i = 0; i < p->blob_len; i++)
+ bufp = pack_hex_byte(bufp, p->blob[i]);
+ if ((copy_to_user(buffer, ascii_buf, 2 * p->blob_len)) != 0) {
+ kfree(ascii_buf);
+ return -EFAULT;
+ }
+ kfree(ascii_buf);
+ return 2 * p->blob_len;
+}
+
+/*
+ * trusted_destroy - before freeing the key, clear the decrypted data
+ */
+static void trusted_destroy(struct key *key)
+{
+ struct trusted_key_payload *p = key->payload.data;
+
+ if (!p)
+ return;
+ memset(p->key, 0, p->key_len);
+ kfree(key->payload.data);
+}
+
+struct key_type key_type_trusted = {
+ .name = "trusted",
+ .instantiate = trusted_instantiate,
+ .update = trusted_update,
+ .match = user_match,
+ .destroy = trusted_destroy,
+ .describe = user_describe,
+ .read = trusted_read,
+};
+
+EXPORT_SYMBOL_GPL(key_type_trusted);
+
+static void trusted_shash_release(void)
+{
+ if (hashalg)
+ crypto_free_shash(hashalg);
+ if (hmacalg)
+ crypto_free_shash(hmacalg);
+}
+
+static int __init trusted_shash_alloc(void)
+{
+ int ret;
+
+ hmacalg = crypto_alloc_shash(hmac_alg, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(hmacalg)) {
+ pr_info("trusted_key: could not allocate crypto %s\n",
+ hmac_alg);
+ return PTR_ERR(hmacalg);
+ }
+
+ hashalg = crypto_alloc_shash(hash_alg, 0, CRYPTO_ALG_ASYNC);
+ if (IS_ERR(hashalg)) {
+ pr_info("trusted_key: could not allocate crypto %s\n",
+ hash_alg);
+ ret = PTR_ERR(hashalg);
+ goto hashalg_fail;
+ }
+
+ return 0;
+
+hashalg_fail:
+ crypto_free_shash(hmacalg);
+ return ret;
+}
+
+static int __init init_trusted(void)
+{
+ int ret;
+
+ ret = trusted_shash_alloc();
+ if (ret < 0)
+ return ret;
+ ret = register_key_type(&key_type_trusted);
+ if (ret < 0)
+ trusted_shash_release();
+ return ret;
+}
+
+static void __exit cleanup_trusted(void)
+{
+ trusted_shash_release();
+ unregister_key_type(&key_type_trusted);
+}
+
+late_initcall(init_trusted);
+module_exit(cleanup_trusted);
+
+MODULE_LICENSE("GPL");
diff --git a/security/keys/trusted.h b/security/keys/trusted.h
new file mode 100644
index 00000000..3249fbd2
--- /dev/null
+++ b/security/keys/trusted.h
@@ -0,0 +1,134 @@
+#ifndef __TRUSTED_KEY_H
+#define __TRUSTED_KEY_H
+
+/* implementation specific TPM constants */
+#define MAX_PCRINFO_SIZE 64
+#define MAX_BUF_SIZE 512
+#define TPM_GETRANDOM_SIZE 14
+#define TPM_OSAP_SIZE 36
+#define TPM_OIAP_SIZE 10
+#define TPM_SEAL_SIZE 87
+#define TPM_UNSEAL_SIZE 104
+#define TPM_SIZE_OFFSET 2
+#define TPM_RETURN_OFFSET 6
+#define TPM_DATA_OFFSET 10
+
+#define LOAD32(buffer, offset) (ntohl(*(uint32_t *)&buffer[offset]))
+#define LOAD32N(buffer, offset) (*(uint32_t *)&buffer[offset])
+#define LOAD16(buffer, offset) (ntohs(*(uint16_t *)&buffer[offset]))
+
+struct tpm_buf {
+ int len;
+ unsigned char data[MAX_BUF_SIZE];
+};
+
+#define INIT_BUF(tb) (tb->len = 0)
+
+struct osapsess {
+ uint32_t handle;
+ unsigned char secret[SHA1_DIGEST_SIZE];
+ unsigned char enonce[TPM_NONCE_SIZE];
+};
+
+/* discrete values, but have to store in uint16_t for TPM use */
+enum {
+ SEAL_keytype = 1,
+ SRK_keytype = 4
+};
+
+struct trusted_key_options {
+ uint16_t keytype;
+ uint32_t keyhandle;
+ unsigned char keyauth[SHA1_DIGEST_SIZE];
+ unsigned char blobauth[SHA1_DIGEST_SIZE];
+ uint32_t pcrinfo_len;
+ unsigned char pcrinfo[MAX_PCRINFO_SIZE];
+ int pcrlock;
+};
+
+#define TPM_DEBUG 0
+
+#if TPM_DEBUG
+static inline void dump_options(struct trusted_key_options *o)
+{
+ pr_info("trusted_key: sealing key type %d\n", o->keytype);
+ pr_info("trusted_key: sealing key handle %0X\n", o->keyhandle);
+ pr_info("trusted_key: pcrlock %d\n", o->pcrlock);
+ pr_info("trusted_key: pcrinfo %d\n", o->pcrinfo_len);
+ print_hex_dump(KERN_INFO, "pcrinfo ", DUMP_PREFIX_NONE,
+ 16, 1, o->pcrinfo, o->pcrinfo_len, 0);
+}
+
+static inline void dump_payload(struct trusted_key_payload *p)
+{
+ pr_info("trusted_key: key_len %d\n", p->key_len);
+ print_hex_dump(KERN_INFO, "key ", DUMP_PREFIX_NONE,
+ 16, 1, p->key, p->key_len, 0);
+ pr_info("trusted_key: bloblen %d\n", p->blob_len);
+ print_hex_dump(KERN_INFO, "blob ", DUMP_PREFIX_NONE,
+ 16, 1, p->blob, p->blob_len, 0);
+ pr_info("trusted_key: migratable %d\n", p->migratable);
+}
+
+static inline void dump_sess(struct osapsess *s)
+{
+ print_hex_dump(KERN_INFO, "trusted-key: handle ", DUMP_PREFIX_NONE,
+ 16, 1, &s->handle, 4, 0);
+ pr_info("trusted-key: secret:\n");
+ print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE,
+ 16, 1, &s->secret, SHA1_DIGEST_SIZE, 0);
+ pr_info("trusted-key: enonce:\n");
+ print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE,
+ 16, 1, &s->enonce, SHA1_DIGEST_SIZE, 0);
+}
+
+static inline void dump_tpm_buf(unsigned char *buf)
+{
+ int len;
+
+ pr_info("\ntrusted-key: tpm buffer\n");
+ len = LOAD32(buf, TPM_SIZE_OFFSET);
+ print_hex_dump(KERN_INFO, "", DUMP_PREFIX_NONE, 16, 1, buf, len, 0);
+}
+#else
+static inline void dump_options(struct trusted_key_options *o)
+{
+}
+
+static inline void dump_payload(struct trusted_key_payload *p)
+{
+}
+
+static inline void dump_sess(struct osapsess *s)
+{
+}
+
+static inline void dump_tpm_buf(unsigned char *buf)
+{
+}
+#endif
+
+static inline void store8(struct tpm_buf *buf, const unsigned char value)
+{
+ buf->data[buf->len++] = value;
+}
+
+static inline void store16(struct tpm_buf *buf, const uint16_t value)
+{
+ *(uint16_t *) & buf->data[buf->len] = htons(value);
+ buf->len += sizeof value;
+}
+
+static inline void store32(struct tpm_buf *buf, const uint32_t value)
+{
+ *(uint32_t *) & buf->data[buf->len] = htonl(value);
+ buf->len += sizeof value;
+}
+
+static inline void storebytes(struct tpm_buf *buf, const unsigned char *in,
+ const int len)
+{
+ memcpy(buf->data + buf->len, in, len);
+ buf->len += len;
+}
+#endif
diff --git a/security/keys/user_defined.c b/security/keys/user_defined.c
new file mode 100644
index 00000000..69ff52c0
--- /dev/null
+++ b/security/keys/user_defined.c
@@ -0,0 +1,191 @@
+/* user_defined.c: user defined key type
+ *
+ * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
+ * Written by David Howells (dhowells@redhat.com)
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ */
+
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/slab.h>
+#include <linux/seq_file.h>
+#include <linux/err.h>
+#include <keys/user-type.h>
+#include <asm/uaccess.h>
+#include "internal.h"
+
+/*
+ * user defined keys take an arbitrary string as the description and an
+ * arbitrary blob of data as the payload
+ */
+struct key_type key_type_user = {
+ .name = "user",
+ .instantiate = user_instantiate,
+ .update = user_update,
+ .match = user_match,
+ .revoke = user_revoke,
+ .destroy = user_destroy,
+ .describe = user_describe,
+ .read = user_read,
+};
+
+EXPORT_SYMBOL_GPL(key_type_user);
+
+/*
+ * instantiate a user defined key
+ */
+int user_instantiate(struct key *key, const void *data, size_t datalen)
+{
+ struct user_key_payload *upayload;
+ int ret;
+
+ ret = -EINVAL;
+ if (datalen <= 0 || datalen > 32767 || !data)
+ goto error;
+
+ ret = key_payload_reserve(key, datalen);
+ if (ret < 0)
+ goto error;
+
+ ret = -ENOMEM;
+ upayload = kmalloc(sizeof(*upayload) + datalen, GFP_KERNEL);
+ if (!upayload)
+ goto error;
+
+ /* attach the data */
+ upayload->datalen = datalen;
+ memcpy(upayload->data, data, datalen);
+ rcu_assign_pointer(key->payload.data, upayload);
+ ret = 0;
+
+error:
+ return ret;
+}
+
+EXPORT_SYMBOL_GPL(user_instantiate);
+
+/*
+ * update a user defined key
+ * - the key's semaphore is write-locked
+ */
+int user_update(struct key *key, const void *data, size_t datalen)
+{
+ struct user_key_payload *upayload, *zap;
+ int ret;
+
+ ret = -EINVAL;
+ if (datalen <= 0 || datalen > 32767 || !data)
+ goto error;
+
+ /* construct a replacement payload */
+ ret = -ENOMEM;
+ upayload = kmalloc(sizeof(*upayload) + datalen, GFP_KERNEL);
+ if (!upayload)
+ goto error;
+
+ upayload->datalen = datalen;
+ memcpy(upayload->data, data, datalen);
+
+ /* check the quota and attach the new data */
+ zap = upayload;
+
+ ret = key_payload_reserve(key, datalen);
+
+ if (ret == 0) {
+ /* attach the new data, displacing the old */
+ zap = key->payload.data;
+ rcu_assign_pointer(key->payload.data, upayload);
+ key->expiry = 0;
+ }
+
+ if (zap)
+ kfree_rcu(zap, rcu);
+
+error:
+ return ret;
+}
+
+EXPORT_SYMBOL_GPL(user_update);
+
+/*
+ * match users on their name
+ */
+int user_match(const struct key *key, const void *description)
+{
+ return strcmp(key->description, description) == 0;
+}
+
+EXPORT_SYMBOL_GPL(user_match);
+
+/*
+ * dispose of the links from a revoked keyring
+ * - called with the key sem write-locked
+ */
+void user_revoke(struct key *key)
+{
+ struct user_key_payload *upayload = key->payload.data;
+
+ /* clear the quota */
+ key_payload_reserve(key, 0);
+
+ if (upayload) {
+ rcu_assign_pointer(key->payload.data, NULL);
+ kfree_rcu(upayload, rcu);
+ }
+}
+
+EXPORT_SYMBOL(user_revoke);
+
+/*
+ * dispose of the data dangling from the corpse of a user key
+ */
+void user_destroy(struct key *key)
+{
+ struct user_key_payload *upayload = key->payload.data;
+
+ kfree(upayload);
+}
+
+EXPORT_SYMBOL_GPL(user_destroy);
+
+/*
+ * describe the user key
+ */
+void user_describe(const struct key *key, struct seq_file *m)
+{
+ seq_puts(m, key->description);
+ if (key_is_instantiated(key))
+ seq_printf(m, ": %u", key->datalen);
+}
+
+EXPORT_SYMBOL_GPL(user_describe);
+
+/*
+ * read the key data
+ * - the key's semaphore is read-locked
+ */
+long user_read(const struct key *key, char __user *buffer, size_t buflen)
+{
+ struct user_key_payload *upayload;
+ long ret;
+
+ upayload = rcu_dereference_key(key);
+ ret = upayload->datalen;
+
+ /* we can return the data as is */
+ if (buffer && buflen > 0) {
+ if (buflen > upayload->datalen)
+ buflen = upayload->datalen;
+
+ if (copy_to_user(buffer, upayload->data, buflen) != 0)
+ ret = -EFAULT;
+ }
+
+ return ret;
+}
+
+EXPORT_SYMBOL_GPL(user_read);