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author | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
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committer | root <root@artemis.panaceas.org> | 2015-12-25 04:40:36 +0000 |
commit | 849369d6c66d3054688672f97d31fceb8e8230fb (patch) | |
tree | 6135abc790ca67dedbe07c39806591e70eda81ce /crypto/ablkcipher.c | |
download | linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.gz linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.tar.bz2 linux-3.0.35-kobo-849369d6c66d3054688672f97d31fceb8e8230fb.zip |
initial_commit
Diffstat (limited to 'crypto/ablkcipher.c')
-rw-r--r-- | crypto/ablkcipher.c | 663 |
1 files changed, 663 insertions, 0 deletions
diff --git a/crypto/ablkcipher.c b/crypto/ablkcipher.c new file mode 100644 index 00000000..fdc67d38 --- /dev/null +++ b/crypto/ablkcipher.c @@ -0,0 +1,663 @@ +/* + * Asynchronous block chaining cipher operations. + * + * This is the asynchronous version of blkcipher.c indicating completion + * via a callback. + * + * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au> + * + * 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 <crypto/internal/skcipher.h> +#include <linux/cpumask.h> +#include <linux/err.h> +#include <linux/init.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/rtnetlink.h> +#include <linux/sched.h> +#include <linux/slab.h> +#include <linux/seq_file.h> + +#include <crypto/scatterwalk.h> + +#include "internal.h" + +static const char *skcipher_default_geniv __read_mostly; + +struct ablkcipher_buffer { + struct list_head entry; + struct scatter_walk dst; + unsigned int len; + void *data; +}; + +enum { + ABLKCIPHER_WALK_SLOW = 1 << 0, +}; + +static inline void ablkcipher_buffer_write(struct ablkcipher_buffer *p) +{ + scatterwalk_copychunks(p->data, &p->dst, p->len, 1); +} + +void __ablkcipher_walk_complete(struct ablkcipher_walk *walk) +{ + struct ablkcipher_buffer *p, *tmp; + + list_for_each_entry_safe(p, tmp, &walk->buffers, entry) { + ablkcipher_buffer_write(p); + list_del(&p->entry); + kfree(p); + } +} +EXPORT_SYMBOL_GPL(__ablkcipher_walk_complete); + +static inline void ablkcipher_queue_write(struct ablkcipher_walk *walk, + struct ablkcipher_buffer *p) +{ + p->dst = walk->out; + list_add_tail(&p->entry, &walk->buffers); +} + +/* Get a spot of the specified length that does not straddle a page. + * The caller needs to ensure that there is enough space for this operation. + */ +static inline u8 *ablkcipher_get_spot(u8 *start, unsigned int len) +{ + u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK); + return max(start, end_page); +} + +static inline unsigned int ablkcipher_done_slow(struct ablkcipher_walk *walk, + unsigned int bsize) +{ + unsigned int n = bsize; + + for (;;) { + unsigned int len_this_page = scatterwalk_pagelen(&walk->out); + + if (len_this_page > n) + len_this_page = n; + scatterwalk_advance(&walk->out, n); + if (n == len_this_page) + break; + n -= len_this_page; + scatterwalk_start(&walk->out, scatterwalk_sg_next(walk->out.sg)); + } + + return bsize; +} + +static inline unsigned int ablkcipher_done_fast(struct ablkcipher_walk *walk, + unsigned int n) +{ + scatterwalk_advance(&walk->in, n); + scatterwalk_advance(&walk->out, n); + + return n; +} + +static int ablkcipher_walk_next(struct ablkcipher_request *req, + struct ablkcipher_walk *walk); + +int ablkcipher_walk_done(struct ablkcipher_request *req, + struct ablkcipher_walk *walk, int err) +{ + struct crypto_tfm *tfm = req->base.tfm; + unsigned int nbytes = 0; + + if (likely(err >= 0)) { + unsigned int n = walk->nbytes - err; + + if (likely(!(walk->flags & ABLKCIPHER_WALK_SLOW))) + n = ablkcipher_done_fast(walk, n); + else if (WARN_ON(err)) { + err = -EINVAL; + goto err; + } else + n = ablkcipher_done_slow(walk, n); + + nbytes = walk->total - n; + err = 0; + } + + scatterwalk_done(&walk->in, 0, nbytes); + scatterwalk_done(&walk->out, 1, nbytes); + +err: + walk->total = nbytes; + walk->nbytes = nbytes; + + if (nbytes) { + crypto_yield(req->base.flags); + return ablkcipher_walk_next(req, walk); + } + + if (walk->iv != req->info) + memcpy(req->info, walk->iv, tfm->crt_ablkcipher.ivsize); + kfree(walk->iv_buffer); + + return err; +} +EXPORT_SYMBOL_GPL(ablkcipher_walk_done); + +static inline int ablkcipher_next_slow(struct ablkcipher_request *req, + struct ablkcipher_walk *walk, + unsigned int bsize, + unsigned int alignmask, + void **src_p, void **dst_p) +{ + unsigned aligned_bsize = ALIGN(bsize, alignmask + 1); + struct ablkcipher_buffer *p; + void *src, *dst, *base; + unsigned int n; + + n = ALIGN(sizeof(struct ablkcipher_buffer), alignmask + 1); + n += (aligned_bsize * 3 - (alignmask + 1) + + (alignmask & ~(crypto_tfm_ctx_alignment() - 1))); + + p = kmalloc(n, GFP_ATOMIC); + if (!p) + return ablkcipher_walk_done(req, walk, -ENOMEM); + + base = p + 1; + + dst = (u8 *)ALIGN((unsigned long)base, alignmask + 1); + src = dst = ablkcipher_get_spot(dst, bsize); + + p->len = bsize; + p->data = dst; + + scatterwalk_copychunks(src, &walk->in, bsize, 0); + + ablkcipher_queue_write(walk, p); + + walk->nbytes = bsize; + walk->flags |= ABLKCIPHER_WALK_SLOW; + + *src_p = src; + *dst_p = dst; + + return 0; +} + +static inline int ablkcipher_copy_iv(struct ablkcipher_walk *walk, + struct crypto_tfm *tfm, + unsigned int alignmask) +{ + unsigned bs = walk->blocksize; + unsigned int ivsize = tfm->crt_ablkcipher.ivsize; + unsigned aligned_bs = ALIGN(bs, alignmask + 1); + unsigned int size = aligned_bs * 2 + ivsize + max(aligned_bs, ivsize) - + (alignmask + 1); + u8 *iv; + + size += alignmask & ~(crypto_tfm_ctx_alignment() - 1); + walk->iv_buffer = kmalloc(size, GFP_ATOMIC); + if (!walk->iv_buffer) + return -ENOMEM; + + iv = (u8 *)ALIGN((unsigned long)walk->iv_buffer, alignmask + 1); + iv = ablkcipher_get_spot(iv, bs) + aligned_bs; + iv = ablkcipher_get_spot(iv, bs) + aligned_bs; + iv = ablkcipher_get_spot(iv, ivsize); + + walk->iv = memcpy(iv, walk->iv, ivsize); + return 0; +} + +static inline int ablkcipher_next_fast(struct ablkcipher_request *req, + struct ablkcipher_walk *walk) +{ + walk->src.page = scatterwalk_page(&walk->in); + walk->src.offset = offset_in_page(walk->in.offset); + walk->dst.page = scatterwalk_page(&walk->out); + walk->dst.offset = offset_in_page(walk->out.offset); + + return 0; +} + +static int ablkcipher_walk_next(struct ablkcipher_request *req, + struct ablkcipher_walk *walk) +{ + struct crypto_tfm *tfm = req->base.tfm; + unsigned int alignmask, bsize, n; + void *src, *dst; + int err; + + alignmask = crypto_tfm_alg_alignmask(tfm); + n = walk->total; + if (unlikely(n < crypto_tfm_alg_blocksize(tfm))) { + req->base.flags |= CRYPTO_TFM_RES_BAD_BLOCK_LEN; + return ablkcipher_walk_done(req, walk, -EINVAL); + } + + walk->flags &= ~ABLKCIPHER_WALK_SLOW; + src = dst = NULL; + + bsize = min(walk->blocksize, n); + n = scatterwalk_clamp(&walk->in, n); + n = scatterwalk_clamp(&walk->out, n); + + if (n < bsize || + !scatterwalk_aligned(&walk->in, alignmask) || + !scatterwalk_aligned(&walk->out, alignmask)) { + err = ablkcipher_next_slow(req, walk, bsize, alignmask, + &src, &dst); + goto set_phys_lowmem; + } + + walk->nbytes = n; + + return ablkcipher_next_fast(req, walk); + +set_phys_lowmem: + if (err >= 0) { + walk->src.page = virt_to_page(src); + walk->dst.page = virt_to_page(dst); + walk->src.offset = ((unsigned long)src & (PAGE_SIZE - 1)); + walk->dst.offset = ((unsigned long)dst & (PAGE_SIZE - 1)); + } + + return err; +} + +static int ablkcipher_walk_first(struct ablkcipher_request *req, + struct ablkcipher_walk *walk) +{ + struct crypto_tfm *tfm = req->base.tfm; + unsigned int alignmask; + + alignmask = crypto_tfm_alg_alignmask(tfm); + if (WARN_ON_ONCE(in_irq())) + return -EDEADLK; + + walk->nbytes = walk->total; + if (unlikely(!walk->total)) + return 0; + + walk->iv_buffer = NULL; + walk->iv = req->info; + if (unlikely(((unsigned long)walk->iv & alignmask))) { + int err = ablkcipher_copy_iv(walk, tfm, alignmask); + if (err) + return err; + } + + scatterwalk_start(&walk->in, walk->in.sg); + scatterwalk_start(&walk->out, walk->out.sg); + + return ablkcipher_walk_next(req, walk); +} + +int ablkcipher_walk_phys(struct ablkcipher_request *req, + struct ablkcipher_walk *walk) +{ + walk->blocksize = crypto_tfm_alg_blocksize(req->base.tfm); + return ablkcipher_walk_first(req, walk); +} +EXPORT_SYMBOL_GPL(ablkcipher_walk_phys); + +static int setkey_unaligned(struct crypto_ablkcipher *tfm, const u8 *key, + unsigned int keylen) +{ + struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm); + unsigned long alignmask = crypto_ablkcipher_alignmask(tfm); + int ret; + u8 *buffer, *alignbuffer; + unsigned long absize; + + absize = keylen + alignmask; + buffer = kmalloc(absize, GFP_ATOMIC); + if (!buffer) + return -ENOMEM; + + alignbuffer = (u8 *)ALIGN((unsigned long)buffer, alignmask + 1); + memcpy(alignbuffer, key, keylen); + ret = cipher->setkey(tfm, alignbuffer, keylen); + memset(alignbuffer, 0, keylen); + kfree(buffer); + return ret; +} + +static int setkey(struct crypto_ablkcipher *tfm, const u8 *key, + unsigned int keylen) +{ + struct ablkcipher_alg *cipher = crypto_ablkcipher_alg(tfm); + unsigned long alignmask = crypto_ablkcipher_alignmask(tfm); + + if (keylen < cipher->min_keysize || keylen > cipher->max_keysize) { + crypto_ablkcipher_set_flags(tfm, CRYPTO_TFM_RES_BAD_KEY_LEN); + return -EINVAL; + } + + if ((unsigned long)key & alignmask) + return setkey_unaligned(tfm, key, keylen); + + return cipher->setkey(tfm, key, keylen); +} + +static unsigned int crypto_ablkcipher_ctxsize(struct crypto_alg *alg, u32 type, + u32 mask) +{ + return alg->cra_ctxsize; +} + +int skcipher_null_givencrypt(struct skcipher_givcrypt_request *req) +{ + return crypto_ablkcipher_encrypt(&req->creq); +} + +int skcipher_null_givdecrypt(struct skcipher_givcrypt_request *req) +{ + return crypto_ablkcipher_decrypt(&req->creq); +} + +static int crypto_init_ablkcipher_ops(struct crypto_tfm *tfm, u32 type, + u32 mask) +{ + struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher; + struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher; + + if (alg->ivsize > PAGE_SIZE / 8) + return -EINVAL; + + crt->setkey = setkey; + crt->encrypt = alg->encrypt; + crt->decrypt = alg->decrypt; + if (!alg->ivsize) { + crt->givencrypt = skcipher_null_givencrypt; + crt->givdecrypt = skcipher_null_givdecrypt; + } + crt->base = __crypto_ablkcipher_cast(tfm); + crt->ivsize = alg->ivsize; + + return 0; +} + +static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg) + __attribute__ ((unused)); +static void crypto_ablkcipher_show(struct seq_file *m, struct crypto_alg *alg) +{ + struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher; + + seq_printf(m, "type : ablkcipher\n"); + seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ? + "yes" : "no"); + seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); + seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize); + seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize); + seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize); + seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<default>"); +} + +const struct crypto_type crypto_ablkcipher_type = { + .ctxsize = crypto_ablkcipher_ctxsize, + .init = crypto_init_ablkcipher_ops, +#ifdef CONFIG_PROC_FS + .show = crypto_ablkcipher_show, +#endif +}; +EXPORT_SYMBOL_GPL(crypto_ablkcipher_type); + +static int no_givdecrypt(struct skcipher_givcrypt_request *req) +{ + return -ENOSYS; +} + +static int crypto_init_givcipher_ops(struct crypto_tfm *tfm, u32 type, + u32 mask) +{ + struct ablkcipher_alg *alg = &tfm->__crt_alg->cra_ablkcipher; + struct ablkcipher_tfm *crt = &tfm->crt_ablkcipher; + + if (alg->ivsize > PAGE_SIZE / 8) + return -EINVAL; + + crt->setkey = tfm->__crt_alg->cra_flags & CRYPTO_ALG_GENIV ? + alg->setkey : setkey; + crt->encrypt = alg->encrypt; + crt->decrypt = alg->decrypt; + crt->givencrypt = alg->givencrypt; + crt->givdecrypt = alg->givdecrypt ?: no_givdecrypt; + crt->base = __crypto_ablkcipher_cast(tfm); + crt->ivsize = alg->ivsize; + + return 0; +} + +static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg) + __attribute__ ((unused)); +static void crypto_givcipher_show(struct seq_file *m, struct crypto_alg *alg) +{ + struct ablkcipher_alg *ablkcipher = &alg->cra_ablkcipher; + + seq_printf(m, "type : givcipher\n"); + seq_printf(m, "async : %s\n", alg->cra_flags & CRYPTO_ALG_ASYNC ? + "yes" : "no"); + seq_printf(m, "blocksize : %u\n", alg->cra_blocksize); + seq_printf(m, "min keysize : %u\n", ablkcipher->min_keysize); + seq_printf(m, "max keysize : %u\n", ablkcipher->max_keysize); + seq_printf(m, "ivsize : %u\n", ablkcipher->ivsize); + seq_printf(m, "geniv : %s\n", ablkcipher->geniv ?: "<built-in>"); +} + +const struct crypto_type crypto_givcipher_type = { + .ctxsize = crypto_ablkcipher_ctxsize, + .init = crypto_init_givcipher_ops, +#ifdef CONFIG_PROC_FS + .show = crypto_givcipher_show, +#endif +}; +EXPORT_SYMBOL_GPL(crypto_givcipher_type); + +const char *crypto_default_geniv(const struct crypto_alg *alg) +{ + if (((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) == + CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize : + alg->cra_ablkcipher.ivsize) != + alg->cra_blocksize) + return "chainiv"; + + return alg->cra_flags & CRYPTO_ALG_ASYNC ? + "eseqiv" : skcipher_default_geniv; +} + +static int crypto_givcipher_default(struct crypto_alg *alg, u32 type, u32 mask) +{ + struct rtattr *tb[3]; + struct { + struct rtattr attr; + struct crypto_attr_type data; + } ptype; + struct { + struct rtattr attr; + struct crypto_attr_alg data; + } palg; + struct crypto_template *tmpl; + struct crypto_instance *inst; + struct crypto_alg *larval; + const char *geniv; + int err; + + larval = crypto_larval_lookup(alg->cra_driver_name, + (type & ~CRYPTO_ALG_TYPE_MASK) | + CRYPTO_ALG_TYPE_GIVCIPHER, + mask | CRYPTO_ALG_TYPE_MASK); + err = PTR_ERR(larval); + if (IS_ERR(larval)) + goto out; + + err = -EAGAIN; + if (!crypto_is_larval(larval)) + goto drop_larval; + + ptype.attr.rta_len = sizeof(ptype); + ptype.attr.rta_type = CRYPTOA_TYPE; + ptype.data.type = type | CRYPTO_ALG_GENIV; + /* GENIV tells the template that we're making a default geniv. */ + ptype.data.mask = mask | CRYPTO_ALG_GENIV; + tb[0] = &ptype.attr; + + palg.attr.rta_len = sizeof(palg); + palg.attr.rta_type = CRYPTOA_ALG; + /* Must use the exact name to locate ourselves. */ + memcpy(palg.data.name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME); + tb[1] = &palg.attr; + + tb[2] = NULL; + + if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) == + CRYPTO_ALG_TYPE_BLKCIPHER) + geniv = alg->cra_blkcipher.geniv; + else + geniv = alg->cra_ablkcipher.geniv; + + if (!geniv) + geniv = crypto_default_geniv(alg); + + tmpl = crypto_lookup_template(geniv); + err = -ENOENT; + if (!tmpl) + goto kill_larval; + + inst = tmpl->alloc(tb); + err = PTR_ERR(inst); + if (IS_ERR(inst)) + goto put_tmpl; + + if ((err = crypto_register_instance(tmpl, inst))) { + tmpl->free(inst); + goto put_tmpl; + } + + /* Redo the lookup to use the instance we just registered. */ + err = -EAGAIN; + +put_tmpl: + crypto_tmpl_put(tmpl); +kill_larval: + crypto_larval_kill(larval); +drop_larval: + crypto_mod_put(larval); +out: + crypto_mod_put(alg); + return err; +} + +static struct crypto_alg *crypto_lookup_skcipher(const char *name, u32 type, + u32 mask) +{ + struct crypto_alg *alg; + + alg = crypto_alg_mod_lookup(name, type, mask); + if (IS_ERR(alg)) + return alg; + + if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) == + CRYPTO_ALG_TYPE_GIVCIPHER) + return alg; + + if (!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) == + CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize : + alg->cra_ablkcipher.ivsize)) + return alg; + + crypto_mod_put(alg); + alg = crypto_alg_mod_lookup(name, type | CRYPTO_ALG_TESTED, + mask & ~CRYPTO_ALG_TESTED); + if (IS_ERR(alg)) + return alg; + + if ((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) == + CRYPTO_ALG_TYPE_GIVCIPHER) { + if ((alg->cra_flags ^ type ^ ~mask) & CRYPTO_ALG_TESTED) { + crypto_mod_put(alg); + alg = ERR_PTR(-ENOENT); + } + return alg; + } + + BUG_ON(!((alg->cra_flags & CRYPTO_ALG_TYPE_MASK) == + CRYPTO_ALG_TYPE_BLKCIPHER ? alg->cra_blkcipher.ivsize : + alg->cra_ablkcipher.ivsize)); + + return ERR_PTR(crypto_givcipher_default(alg, type, mask)); +} + +int crypto_grab_skcipher(struct crypto_skcipher_spawn *spawn, const char *name, + u32 type, u32 mask) +{ + struct crypto_alg *alg; + int err; + + type = crypto_skcipher_type(type); + mask = crypto_skcipher_mask(mask); + + alg = crypto_lookup_skcipher(name, type, mask); + if (IS_ERR(alg)) + return PTR_ERR(alg); + + err = crypto_init_spawn(&spawn->base, alg, spawn->base.inst, mask); + crypto_mod_put(alg); + return err; +} +EXPORT_SYMBOL_GPL(crypto_grab_skcipher); + +struct crypto_ablkcipher *crypto_alloc_ablkcipher(const char *alg_name, + u32 type, u32 mask) +{ + struct crypto_tfm *tfm; + int err; + + type = crypto_skcipher_type(type); + mask = crypto_skcipher_mask(mask); + + for (;;) { + struct crypto_alg *alg; + + alg = crypto_lookup_skcipher(alg_name, type, mask); + if (IS_ERR(alg)) { + err = PTR_ERR(alg); + goto err; + } + + tfm = __crypto_alloc_tfm(alg, type, mask); + if (!IS_ERR(tfm)) + return __crypto_ablkcipher_cast(tfm); + + crypto_mod_put(alg); + err = PTR_ERR(tfm); + +err: + if (err != -EAGAIN) + break; + if (signal_pending(current)) { + err = -EINTR; + break; + } + } + + return ERR_PTR(err); +} +EXPORT_SYMBOL_GPL(crypto_alloc_ablkcipher); + +static int __init skcipher_module_init(void) +{ + skcipher_default_geniv = num_possible_cpus() > 1 ? + "eseqiv" : "chainiv"; + return 0; +} + +static void skcipher_module_exit(void) +{ +} + +module_init(skcipher_module_init); +module_exit(skcipher_module_exit); |