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-rw-r--r--target/linux/generic-2.4/patches/106-mppe_mppc.patch1642
1 files changed, 0 insertions, 1642 deletions
diff --git a/target/linux/generic-2.4/patches/106-mppe_mppc.patch b/target/linux/generic-2.4/patches/106-mppe_mppc.patch
deleted file mode 100644
index afd2e601a2..0000000000
--- a/target/linux/generic-2.4/patches/106-mppe_mppc.patch
+++ /dev/null
@@ -1,1642 +0,0 @@
-MPPE/MPPC kernel module for Linux
-
-Microsoft Point-to-Point Encryption / Compression support
-
- http://www.polbox.com/h/hs001/linux-2.4.29-mppe-mppc-1.3.patch.gz
-
---- a/Documentation/Configure.help
-+++ b/Documentation/Configure.help
-@@ -9986,6 +9986,28 @@ CONFIG_PPP_BSDCOMP
- module; it is called bsd_comp.o and will show up in the directory
- modules once you have said "make modules". If unsure, say N.
-
-+Microsoft PPP compression/encryption (MPPC/MPPE)
-+CONFIG_PPP_MPPE_MPPC
-+ Support for the Microsoft Point-To-Point Compression (RFC2118) and
-+ Microsoft Point-To-Point Encryption (RFC3078). These protocols are
-+ supported by Microsoft Windows and wide range of "hardware" access
-+ servers. MPPE is common protocol in Virtual Private Networks. According
-+ to RFC3078, MPPE supports 40, 56 and 128-bit key lengths. Depending on
-+ PPP daemon configuration on both ends of the link, following scenarios
-+ are possible:
-+ - only compression (MPPC) is used,
-+ - only encryption (MPPE) is used,
-+ - compression and encryption (MPPC+MPPE) are used.
-+
-+ Please note that Hi/Fn (http://www.hifn.com) holds patent on MPPC so
-+ you should check if this patent is valid in your country in order to
-+ avoid legal problems.
-+
-+ For more information please visit http://free.polbox.pl/h/hs001
-+
-+ To compile this driver as a module, choose M here. The module will
-+ be called ppp_mppe_mppc.o.
-+
- PPP over Ethernet
- CONFIG_PPPOE
- Support for PPP over Ethernet.
---- a/crypto/Config.in
-+++ b/crypto/Config.in
-@@ -11,7 +11,9 @@ if [ "$CONFIG_INET_AH" = "y" -o \
- "$CONFIG_INET6_AH" = "y" -o \
- "$CONFIG_INET6_AH" = "m" -o \
- "$CONFIG_INET6_ESP" = "y" -o \
-- "$CONFIG_INET6_ESP" = "m" ]; then
-+ "$CONFIG_INET6_ESP" = "m" -o \
-+ "$CONFIG_PPP_MPPE_MPPC" = "y" -o \
-+ "$CONFIG_PPP_MPPE_MPPC" = "m" ]; then
- define_bool CONFIG_CRYPTO y
- else
- bool 'Cryptographic API' CONFIG_CRYPTO
-@@ -51,11 +53,24 @@ if [ "$CONFIG_CRYPTO" = "y" ]; then
- "$CONFIG_INET6_AH" = "y" -o \
- "$CONFIG_INET6_AH" = "m" -o \
- "$CONFIG_INET6_ESP" = "y" -o \
-- "$CONFIG_INET6_ESP" = "m" ]; then
-- define_bool CONFIG_CRYPTO_SHA1 y
-- else
-- tristate ' SHA1 digest algorithm' CONFIG_CRYPTO_SHA1
-+ "$CONFIG_INET6_ESP" = "m" -o \
-+ "$CONFIG_PPP_MPPE_MPPC" = "y" -o \
-+ "$CONFIG_PPP_MPPE_MPPC" = "m" ]; then
-+ if [ "$CONFIG_INET_AH" = "y" -o \
-+ "$CONFIG_INET_ESP" = "y" -o \
-+ "$CONFIG_INET6_AH" = "y" -o \
-+ "$CONFIG_INET6_ESP" = "y" -o \
-+ "$CONFIG_PPP_MPPE_MPPC" = "y" ]; then
-+ define_tristate CONFIG_CRYPTO_SHA1 y
-+ else
-+ if [ "$CONFIG_CRYPTO_SHA1" != "y" -a \
-+ "$CONFIG_CRYPTO_SHA1" != "m" ]; then
-+ define_tristate CONFIG_CRYPTO_SHA1 m
-+ fi
-+ fi
- fi
-+ tristate ' SHA1 digest algorithm' CONFIG_CRYPTO_SHA1
-+
- tristate ' SHA256 digest algorithm' CONFIG_CRYPTO_SHA256
- tristate ' SHA384 and SHA512 digest algorithms' CONFIG_CRYPTO_SHA512
- tristate ' Whirlpool digest algorithms' CONFIG_CRYPTO_WP512
-@@ -76,7 +91,20 @@ if [ "$CONFIG_CRYPTO" = "y" ]; then
- tristate ' TEA and XTEA cipher algorithms' CONFIG_CRYPTO_TEA
- tristate ' Khazad cipher algorithm' CONFIG_CRYPTO_KHAZAD
- tristate ' Anubis cipher algorithm' CONFIG_CRYPTO_ANUBIS
-+
-+ if [ "$CONFIG_PPP_MPPE_MPPC" = "y" -o \
-+ "$CONFIG_PPP_MPPE_MPPC" = "m" ]; then
-+ if [ "$CONFIG_PPP_MPPE_MPPC" = "y" ]; then
-+ define_tristate CONFIG_CRYPTO_ARC4 y
-+ else
-+ if [ "$CONFIG_CRYPTO_ARC4" != "y" -a \
-+ "$CONFIG_CRYPTO_ARC4" != "m" ]; then
-+ define_tristate CONFIG_CRYPTO_ARC4 m
-+ fi
-+ fi
-+ fi
- tristate ' ARC4 cipher algorithm' CONFIG_CRYPTO_ARC4
-+
- if [ "$CONFIG_INET_IPCOMP" = "y" -o \
- "$CONFIG_INET_IPCOMP" = "m" -o \
- "$CONFIG_INET6_IPCOMP" = "y" -o \
---- a/drivers/net/Config.in
-+++ b/drivers/net/Config.in
-@@ -336,6 +336,7 @@ if [ ! "$CONFIG_PPP" = "n" ]; then
- dep_tristate ' PPP support for sync tty ports' CONFIG_PPP_SYNC_TTY $CONFIG_PPP
- dep_tristate ' PPP Deflate compression' CONFIG_PPP_DEFLATE $CONFIG_PPP
- dep_tristate ' PPP BSD-Compress compression' CONFIG_PPP_BSDCOMP $CONFIG_PPP
-+ dep_tristate ' Microsoft PPP compression/encryption (MPPC/MPPE)' CONFIG_PPP_MPPE_MPPC $CONFIG_PPP
- if [ "$CONFIG_EXPERIMENTAL" = "y" ]; then
- dep_tristate ' PPP over Ethernet (EXPERIMENTAL)' CONFIG_PPPOE $CONFIG_PPP
- fi
---- a/drivers/net/Makefile
-+++ b/drivers/net/Makefile
-@@ -166,6 +166,7 @@ obj-$(CONFIG_PPP_ASYNC) += ppp_async.o
- obj-$(CONFIG_PPP_SYNC_TTY) += ppp_synctty.o
- obj-$(CONFIG_PPP_DEFLATE) += ppp_deflate.o
- obj-$(CONFIG_PPP_BSDCOMP) += bsd_comp.o
-+obj-$(CONFIG_PPP_MPPE_MPPC) += ppp_mppe_mppc.o
- obj-$(CONFIG_PPPOE) += pppox.o pppoe.o
-
- obj-$(CONFIG_SLIP) += slip.o
---- a/drivers/net/ppp_generic.c
-+++ b/drivers/net/ppp_generic.c
-@@ -19,7 +19,7 @@
- * PPP driver, written by Michael Callahan and Al Longyear, and
- * subsequently hacked by Paul Mackerras.
- *
-- * ==FILEVERSION 20020217==
-+ * ==FILEVERSION 20040509==
- */
-
- #include <linux/config.h>
-@@ -102,6 +102,7 @@ struct ppp {
- spinlock_t rlock; /* lock for receive side 58 */
- spinlock_t wlock; /* lock for transmit side 5c */
- int mru; /* max receive unit 60 */
-+ int mru_alloc; /* MAX(1500,MRU) for dev_alloc_skb() */
- unsigned int flags; /* control bits 64 */
- unsigned int xstate; /* transmit state bits 68 */
- unsigned int rstate; /* receive state bits 6c */
-@@ -552,7 +553,9 @@ static int ppp_ioctl(struct inode *inode
- case PPPIOCSMRU:
- if (get_user(val, (int *) arg))
- break;
-- ppp->mru = val;
-+ ppp->mru_alloc = ppp->mru = val;
-+ if (ppp->mru_alloc < PPP_MRU)
-+ ppp->mru_alloc = PPP_MRU; /* increase for broken peers */
- err = 0;
- break;
-
-@@ -1025,14 +1028,37 @@ ppp_send_frame(struct ppp *ppp, struct s
- case PPP_CCP:
- /* peek at outbound CCP frames */
- ppp_ccp_peek(ppp, skb, 0);
-+ /*
-+ * When LZS or MPPE/MPPC has been negotiated we don't send
-+ * CCP_RESETACK after receiving CCP_RESETREQ; in fact pppd
-+ * sends such a packet but we silently discard it here
-+ */
-+ if (CCP_CODE(skb->data+2) == CCP_RESETACK
-+ && (ppp->xcomp->compress_proto == CI_MPPE
-+ || ppp->xcomp->compress_proto == CI_LZS)) {
-+ --ppp->stats.tx_packets;
-+ ppp->stats.tx_bytes -= skb->len - 2;
-+ kfree_skb(skb);
-+ return;
-+ }
- break;
- }
-
- /* try to do packet compression */
- if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state != 0
- && proto != PPP_LCP && proto != PPP_CCP) {
-- new_skb = alloc_skb(ppp->dev->mtu + ppp->dev->hard_header_len,
-- GFP_ATOMIC);
-+ int comp_ovhd = 0;
-+ /*
-+ * because of possible data expansion when MPPC or LZS
-+ * is used, allocate compressor's buffer 12.5% bigger
-+ * than MTU
-+ */
-+ if (ppp->xcomp->compress_proto == CI_MPPE)
-+ comp_ovhd = ((ppp->dev->mtu * 9) / 8) + 1 + MPPE_OVHD;
-+ else if (ppp->xcomp->compress_proto == CI_LZS)
-+ comp_ovhd = ((ppp->dev->mtu * 9) / 8) + 1 + LZS_OVHD;
-+ new_skb = alloc_skb(ppp->dev->mtu + ppp->dev->hard_header_len
-+ + comp_ovhd, GFP_ATOMIC);
- if (new_skb == 0) {
- printk(KERN_ERR "PPP: no memory (comp pkt)\n");
- goto drop;
-@@ -1050,9 +1076,21 @@ ppp_send_frame(struct ppp *ppp, struct s
- skb = new_skb;
- skb_put(skb, len);
- skb_pull(skb, 2); /* pull off A/C bytes */
-- } else {
-+ } else if (len == 0) {
- /* didn't compress, or CCP not up yet */
- kfree_skb(new_skb);
-+ } else {
-+ /*
-+ * (len < 0)
-+ * MPPE requires that we do not send unencrypted
-+ * frames. The compressor will return -1 if we
-+ * should drop the frame. We cannot simply test
-+ * the compress_proto because MPPE and MPPC share
-+ * the same number.
-+ */
-+ printk(KERN_ERR "ppp: compressor dropped pkt\n");
-+ kfree_skb(new_skb);
-+ goto drop;
- }
- }
-
-@@ -1540,14 +1578,15 @@ ppp_decompress_frame(struct ppp *ppp, st
- int len;
-
- if (proto == PPP_COMP) {
-- ns = dev_alloc_skb(ppp->mru + PPP_HDRLEN);
-+ ns = dev_alloc_skb(ppp->mru_alloc + PPP_HDRLEN);
- if (ns == 0) {
- printk(KERN_ERR "ppp_decompress_frame: no memory\n");
- goto err;
- }
- /* the decompressor still expects the A/C bytes in the hdr */
- len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2,
-- skb->len + 2, ns->data, ppp->mru + PPP_HDRLEN);
-+ skb->len + 2, ns->data,
-+ ppp->mru_alloc + PPP_HDRLEN);
- if (len < 0) {
- /* Pass the compressed frame to pppd as an
- error indication. */
-@@ -1573,7 +1612,14 @@ ppp_decompress_frame(struct ppp *ppp, st
- return skb;
-
- err:
-- ppp->rstate |= SC_DC_ERROR;
-+ if (ppp->rcomp->compress_proto != CI_MPPE
-+ && ppp->rcomp->compress_proto != CI_LZS) {
-+ /*
-+ * If decompression protocol isn't MPPE/MPPC or LZS, we set
-+ * SC_DC_ERROR flag and wait for CCP_RESETACK
-+ */
-+ ppp->rstate |= SC_DC_ERROR;
-+ }
- ppp_receive_error(ppp);
- return skb;
- }
-@@ -2253,6 +2299,7 @@ ppp_create_interface(int unit, int *retp
- /* Initialize the new ppp unit */
- ppp->file.index = unit;
- ppp->mru = PPP_MRU;
-+ ppp->mru_alloc = PPP_MRU;
- init_ppp_file(&ppp->file, INTERFACE);
- ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */
- for (i = 0; i < NUM_NP; ++i)
---- /dev/null
-+++ b/drivers/net/ppp_mppe_mppc.c
-@@ -0,0 +1,1312 @@
-+/*
-+ * ppp_mppe_mppc.c - MPPC/MPPE "compressor/decompressor" module.
-+ *
-+ * Copyright (c) 1994 Árpád Magosányi <mag@bunuel.tii.matav.hu>
-+ * Copyright (c) 1999 Tim Hockin, Cobalt Networks Inc. <thockin@cobaltnet.com>
-+ * Copyright (c) 2002-2005 Jan Dubiec <jdx@slackware.pl>
-+ *
-+ * Permission to use, copy, modify, and distribute this software and its
-+ * documentation is hereby granted, provided that the above copyright
-+ * notice appears in all copies. This software is provided without any
-+ * warranty, express or implied.
-+ *
-+ * The code is based on MPPE kernel module written by Árpád Magosányi and
-+ * Tim Hockin which can be found on http://planetmirror.com/pub/mppe/.
-+ * I have added MPPC and 56 bit session keys support in MPPE.
-+ *
-+ * WARNING! Although this is open source code, its usage in some countries
-+ * (in particular in the USA) may violate Stac Inc. patent for MPPC.
-+ *
-+ * ==FILEVERSION 20050202==
-+ *
-+ */
-+
-+#include <linux/init.h>
-+#include <linux/module.h>
-+#include <linux/mm.h>
-+#include <linux/slab.h>
-+#include <asm/scatterlist.h>
-+#include <linux/vmalloc.h>
-+#include <linux/crypto.h>
-+
-+#include <linux/ppp_defs.h>
-+#include <linux/ppp-comp.h>
-+
-+/*
-+ * In 2.4.x kernels macro offset_in_page() is not defined in linux/mm.h so
-+ * we define it here; PAGE_MASK is defined in asm/page.h which is included
-+ * by linux/mm.h.
-+ */
-+#define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
-+
-+/*
-+ * State for a mppc/mppe "(de)compressor".
-+ */
-+struct ppp_mppe_state {
-+ struct crypto_tfm *arc4_tfm;
-+ struct crypto_tfm *sha1_tfm;
-+ u8 *sha1_digest;
-+ u8 master_key[MPPE_MAX_KEY_LEN];
-+ u8 session_key[MPPE_MAX_KEY_LEN];
-+ u8 mppc; /* do we use compression (MPPC)? */
-+ u8 mppe; /* do we use encryption (MPPE)? */
-+ u8 keylen; /* key length in bytes */
-+ u8 bitkeylen; /* key length in bits */
-+ u16 ccount; /* coherency counter */
-+ u16 bits; /* MPPC/MPPE control bits */
-+ u8 stateless; /* do we use stateless mode? */
-+ u8 nextflushed; /* set A bit in the next outgoing packet;
-+ used only by compressor*/
-+ u8 flushexpected; /* drop packets until A bit is received;
-+ used only by decompressor*/
-+ u8 *hist; /* MPPC history */
-+ u16 *hash; /* Hash table; used only by compressor */
-+ u16 histptr; /* history "cursor" */
-+ int unit;
-+ int debug;
-+ int mru;
-+ struct compstat stats;
-+};
-+
-+#define MPPE_HIST_LEN 8192 /* MPPC history size */
-+#define MPPE_MAX_CCOUNT 0x0FFF /* max. coherency counter value */
-+
-+#define MPPE_BIT_FLUSHED 0x80 /* bit A */
-+#define MPPE_BIT_RESET 0x40 /* bit B */
-+#define MPPE_BIT_COMP 0x20 /* bit C */
-+#define MPPE_BIT_ENCRYPTED 0x10 /* bit D */
-+
-+#define MPPE_SALT0 0xD1 /* values used in MPPE key derivation */
-+#define MPPE_SALT1 0x26 /* according to RFC3079 */
-+#define MPPE_SALT2 0x9E
-+
-+#define MPPE_CCOUNT(x) ((((x)[4] & 0x0f) << 8) + (x)[5])
-+#define MPPE_BITS(x) ((x)[4] & 0xf0)
-+#define MPPE_CTRLHI(x) ((((x)->ccount & 0xf00)>>8)|((x)->bits))
-+#define MPPE_CTRLLO(x) ((x)->ccount & 0xff)
-+
-+/*
-+ * Kernel Crypto API needs its arguments to be in kmalloc'd memory, not in the
-+ * module static data area. That means sha_pad needs to be kmalloc'd. It is done
-+ * in mppe_module_init(). This has been pointed out on 30th July 2004 by Oleg
-+ * Makarenko on pptpclient-devel mailing list.
-+ */
-+#define SHA1_PAD_SIZE 40
-+struct sha_pad {
-+ unsigned char sha_pad1[SHA1_PAD_SIZE];
-+ unsigned char sha_pad2[SHA1_PAD_SIZE];
-+};
-+static struct sha_pad *sha_pad;
-+
-+static inline void
-+setup_sg(struct scatterlist *sg, const void *address, unsigned int length)
-+{
-+ sg[0].page = virt_to_page(address);
-+ sg[0].offset = offset_in_page(address);
-+ sg[0].length = length;
-+}
-+
-+static inline void
-+arc4_setkey(struct ppp_mppe_state *state, const unsigned char *key,
-+ const unsigned int keylen)
-+{
-+ crypto_cipher_setkey(state->arc4_tfm, key, keylen);
-+}
-+
-+static inline void
-+arc4_encrypt(struct ppp_mppe_state *state, const unsigned char *in,
-+ const unsigned int len, unsigned char *out)
-+{
-+ struct scatterlist sgin[4], sgout[4];
-+
-+ setup_sg(sgin, in, len);
-+ setup_sg(sgout, out, len);
-+ crypto_cipher_encrypt(state->arc4_tfm, sgout, sgin, len);
-+}
-+
-+#define arc4_decrypt arc4_encrypt
-+
-+/*
-+ * Key Derivation, from RFC 3078, RFC 3079.
-+ * Equivalent to Get_Key() for MS-CHAP as described in RFC 3079.
-+ */
-+static void
-+get_new_key_from_sha(struct ppp_mppe_state *state, unsigned char *interim_key)
-+{
-+ struct scatterlist sg[4];
-+
-+ setup_sg(&sg[0], state->master_key, state->keylen);
-+ setup_sg(&sg[1], sha_pad->sha_pad1, sizeof(sha_pad->sha_pad1));
-+ setup_sg(&sg[2], state->session_key, state->keylen);
-+ setup_sg(&sg[3], sha_pad->sha_pad2, sizeof(sha_pad->sha_pad2));
-+
-+ crypto_digest_digest (state->sha1_tfm, sg, 4, state->sha1_digest);
-+
-+ memcpy(interim_key, state->sha1_digest, state->keylen);
-+}
-+
-+static void
-+mppe_change_key(struct ppp_mppe_state *state, int initialize)
-+{
-+ unsigned char interim_key[MPPE_MAX_KEY_LEN];
-+
-+ get_new_key_from_sha(state, interim_key);
-+ if (initialize) {
-+ memcpy(state->session_key, interim_key, state->keylen);
-+ } else {
-+ arc4_setkey(state, interim_key, state->keylen);
-+ arc4_encrypt(state, interim_key, state->keylen, state->session_key);
-+ }
-+ if (state->keylen == 8) {
-+ if (state->bitkeylen == 40) {
-+ state->session_key[0] = MPPE_SALT0;
-+ state->session_key[1] = MPPE_SALT1;
-+ state->session_key[2] = MPPE_SALT2;
-+ } else {
-+ state->session_key[0] = MPPE_SALT0;
-+ }
-+ }
-+ arc4_setkey(state, state->session_key, state->keylen);
-+}
-+
-+/* increase 12-bit coherency counter */
-+static inline void
-+mppe_increase_ccount(struct ppp_mppe_state *state)
-+{
-+ state->ccount = (state->ccount + 1) & MPPE_MAX_CCOUNT;
-+ if (state->mppe) {
-+ if (state->stateless) {
-+ mppe_change_key(state, 0);
-+ state->nextflushed = 1;
-+ } else {
-+ if ((state->ccount & 0xff) == 0xff) {
-+ mppe_change_key(state, 0);
-+ }
-+ }
-+ }
-+}
-+
-+/* allocate space for a MPPE/MPPC (de)compressor. */
-+/* comp != 0 -> init compressor */
-+/* comp = 0 -> init decompressor */
-+static void *
-+mppe_alloc(unsigned char *options, int opt_len, int comp)
-+{
-+ struct ppp_mppe_state *state;
-+ unsigned int digestsize;
-+ u8* fname;
-+
-+ fname = comp ? "mppe_comp_alloc" : "mppe_decomp_alloc";
-+
-+ /*
-+ * Hack warning - additionally to the standard MPPC/MPPE configuration
-+ * options, pppd passes to the (de)copressor 8 or 16 byte session key.
-+ * Therefore options[1] contains MPPC/MPPE configuration option length
-+ * (CILEN_MPPE = 6), but the real options length, depending on the key
-+ * length, is 6+8 or 6+16.
-+ */
-+ if (opt_len < CILEN_MPPE) {
-+ printk(KERN_WARNING "%s: wrong options length: %u\n", fname, opt_len);
-+ return NULL;
-+ }
-+
-+ if (options[0] != CI_MPPE || options[1] != CILEN_MPPE ||
-+ (options[2] & ~MPPE_STATELESS) != 0 ||
-+ options[3] != 0 || options[4] != 0 ||
-+ (options[5] & ~(MPPE_128BIT|MPPE_56BIT|MPPE_40BIT|MPPE_MPPC)) != 0 ||
-+ (options[5] & (MPPE_128BIT|MPPE_56BIT|MPPE_40BIT|MPPE_MPPC)) == 0) {
-+ printk(KERN_WARNING "%s: options rejected: o[0]=%02x, o[1]=%02x, "
-+ "o[2]=%02x, o[3]=%02x, o[4]=%02x, o[5]=%02x\n", fname, options[0],
-+ options[1], options[2], options[3], options[4], options[5]);
-+ return NULL;
-+ }
-+
-+ state = (struct ppp_mppe_state *)kmalloc(sizeof(*state), GFP_KERNEL);
-+ if (state == NULL) {
-+ printk(KERN_ERR "%s: cannot allocate space for %scompressor\n", fname,
-+ comp ? "" : "de");
-+ return NULL;
-+ }
-+ memset(state, 0, sizeof(struct ppp_mppe_state));
-+
-+ state->mppc = options[5] & MPPE_MPPC; /* Do we use MPPC? */
-+ state->mppe = options[5] & (MPPE_128BIT | MPPE_56BIT |
-+ MPPE_40BIT); /* Do we use MPPE? */
-+
-+ if (state->mppc) {
-+ /* allocate MPPC history */
-+ state->hist = (u8*)vmalloc(2*MPPE_HIST_LEN*sizeof(u8));
-+ if (state->hist == NULL) {
-+ kfree(state);
-+ printk(KERN_ERR "%s: cannot allocate space for MPPC history\n",
-+ fname);
-+ return NULL;
-+ }
-+
-+ /* allocate hashtable for MPPC compressor */
-+ if (comp) {
-+ state->hash = (u16*)vmalloc(MPPE_HIST_LEN*sizeof(u16));
-+ if (state->hash == NULL) {
-+ vfree(state->hist);
-+ kfree(state);
-+ printk(KERN_ERR "%s: cannot allocate space for MPPC history\n",
-+ fname);
-+ return NULL;
-+ }
-+ }
-+ }
-+
-+ if (state->mppe) { /* specific for MPPE */
-+ /* Load ARC4 algorithm */
-+ state->arc4_tfm = crypto_alloc_tfm("arc4", 0);
-+ if (state->arc4_tfm == NULL) {
-+ if (state->mppc) {
-+ vfree(state->hash);
-+ if (comp)
-+ vfree(state->hist);
-+ }
-+ kfree(state);
-+ printk(KERN_ERR "%s: cannot load ARC4 module\n", fname);
-+ return NULL;
-+ }
-+
-+ /* Load SHA1 algorithm */
-+ state->sha1_tfm = crypto_alloc_tfm("sha1", 0);
-+ if (state->sha1_tfm == NULL) {
-+ crypto_free_tfm(state->arc4_tfm);
-+ if (state->mppc) {
-+ vfree(state->hash);
-+ if (comp)
-+ vfree(state->hist);
-+ }
-+ kfree(state);
-+ printk(KERN_ERR "%s: cannot load SHA1 module\n", fname);
-+ return NULL;
-+ }
-+
-+ digestsize = crypto_tfm_alg_digestsize(state->sha1_tfm);
-+ if (digestsize < MPPE_MAX_KEY_LEN) {
-+ crypto_free_tfm(state->sha1_tfm);
-+ crypto_free_tfm(state->arc4_tfm);
-+ if (state->mppc) {
-+ vfree(state->hash);
-+ if (comp)
-+ vfree(state->hist);
-+ }
-+ kfree(state);
-+ printk(KERN_ERR "%s: CryptoAPI SHA1 digest size too small\n", fname);
-+ }
-+
-+ state->sha1_digest = kmalloc(digestsize, GFP_KERNEL);
-+ if (!state->sha1_digest) {
-+ crypto_free_tfm(state->sha1_tfm);
-+ crypto_free_tfm(state->arc4_tfm);
-+ if (state->mppc) {
-+ vfree(state->hash);
-+ if (comp)
-+ vfree(state->hist);
-+ }
-+ kfree(state);
-+ printk(KERN_ERR "%s: cannot allocate space for SHA1 digest\n", fname);
-+ }
-+
-+ memcpy(state->master_key, options+CILEN_MPPE, MPPE_MAX_KEY_LEN);
-+ memcpy(state->session_key, state->master_key, MPPE_MAX_KEY_LEN);
-+ /* initial key generation is done in mppe_init() */
-+ }
-+
-+ MOD_INC_USE_COUNT;
-+
-+ return (void *) state;
-+}
-+
-+static void *
-+mppe_comp_alloc(unsigned char *options, int opt_len)
-+{
-+ return mppe_alloc(options, opt_len, 1);
-+}
-+
-+static void *
-+mppe_decomp_alloc(unsigned char *options, int opt_len)
-+{
-+ return mppe_alloc(options, opt_len, 0);
-+}
-+
-+/* cleanup the (de)compressor */
-+static void
-+mppe_comp_free(void *arg)
-+{
-+ struct ppp_mppe_state *state = (struct ppp_mppe_state *) arg;
-+
-+ if (state != NULL) {
-+ if (state->mppe) {
-+ if (state->sha1_tfm != NULL)
-+ crypto_free_tfm(state->sha1_tfm);
-+ if (state->arc4_tfm != NULL)
-+ crypto_free_tfm(state->arc4_tfm);
-+ }
-+ if (state->hist != NULL)
-+ vfree(state->hist);
-+ if (state->hash != NULL)
-+ vfree(state->hash);
-+ kfree(state);
-+ }
-+
-+ MOD_DEC_USE_COUNT;
-+}
-+
-+/* init MPPC/MPPE (de)compresor */
-+/* comp != 0 -> init compressor */
-+/* comp = 0 -> init decompressor */
-+static int
-+mppe_init(void *arg, unsigned char *options, int opt_len, int unit,
-+ int hdrlen, int mru, int debug, int comp)
-+{
-+ struct ppp_mppe_state *state = (struct ppp_mppe_state *) arg;
-+ u8* fname;
-+
-+ fname = comp ? "mppe_comp_init" : "mppe_decomp_init";
-+
-+ if (opt_len < CILEN_MPPE) {
-+ if (debug)
-+ printk(KERN_WARNING "%s: wrong options length: %u\n",
-+ fname, opt_len);
-+ return 0;
-+ }
-+
-+ if (options[0] != CI_MPPE || options[1] != CILEN_MPPE ||
-+ (options[2] & ~MPPE_STATELESS) != 0 ||
-+ options[3] != 0 || options[4] != 0 ||
-+ (options[5] & ~(MPPE_56BIT|MPPE_128BIT|MPPE_40BIT|MPPE_MPPC)) != 0 ||
-+ (options[5] & (MPPE_56BIT|MPPE_128BIT|MPPE_40BIT|MPPE_MPPC)) == 0) {
-+ if (debug)
-+ printk(KERN_WARNING "%s: options rejected: o[0]=%02x, o[1]=%02x, "
-+ "o[2]=%02x, o[3]=%02x, o[4]=%02x, o[5]=%02x\n", fname,
-+ options[0], options[1], options[2], options[3], options[4],
-+ options[5]);
-+ return 0;
-+ }
-+
-+ if ((options[5] & ~MPPE_MPPC) != MPPE_128BIT &&
-+ (options[5] & ~MPPE_MPPC) != MPPE_56BIT &&
-+ (options[5] & ~MPPE_MPPC) != MPPE_40BIT &&
-+ (options[5] & MPPE_MPPC) != MPPE_MPPC) {
-+ if (debug)
-+ printk(KERN_WARNING "%s: don't know what to do: o[5]=%02x\n",
-+ fname, options[5]);
-+ return 0;
-+ }
-+
-+ state->mppc = options[5] & MPPE_MPPC; /* Do we use MPPC? */
-+ state->mppe = options[5] & (MPPE_128BIT | MPPE_56BIT |
-+ MPPE_40BIT); /* Do we use MPPE? */
-+ state->stateless = options[2] & MPPE_STATELESS; /* Do we use stateless mode? */
-+
-+ switch (state->mppe) {
-+ case MPPE_40BIT: /* 40 bit key */
-+ state->keylen = 8;
-+ state->bitkeylen = 40;
-+ break;
-+ case MPPE_56BIT: /* 56 bit key */
-+ state->keylen = 8;
-+ state->bitkeylen = 56;
-+ break;
-+ case MPPE_128BIT: /* 128 bit key */
-+ state->keylen = 16;
-+ state->bitkeylen = 128;
-+ break;
-+ default:
-+ state->keylen = 0;
-+ state->bitkeylen = 0;
-+ }
-+
-+ state->ccount = MPPE_MAX_CCOUNT;
-+ state->bits = 0;
-+ state->unit = unit;
-+ state->debug = debug;
-+ state->histptr = MPPE_HIST_LEN;
-+ if (state->mppc) { /* reset history if MPPC was negotiated */
-+ memset(state->hist, 0, 2*MPPE_HIST_LEN*sizeof(u8));
-+ }
-+
-+ if (state->mppe) { /* generate initial session keys */
-+ mppe_change_key(state, 1);
-+ }
-+
-+ if (comp) { /* specific for compressor */
-+ state->nextflushed = 1;
-+ } else { /* specific for decompressor */
-+ state->mru = mru;
-+ state->flushexpected = 1;
-+ }
-+
-+ return 1;
-+}
-+
-+static int
-+mppe_comp_init(void *arg, unsigned char *options, int opt_len, int unit,
-+ int hdrlen, int debug)
-+{
-+ return mppe_init(arg, options, opt_len, unit, hdrlen, 0, debug, 1);
-+}
-+
-+
-+static int
-+mppe_decomp_init(void *arg, unsigned char *options, int opt_len, int unit,
-+ int hdrlen, int mru, int debug)
-+{
-+ return mppe_init(arg, options, opt_len, unit, hdrlen, mru, debug, 0);
-+}
-+
-+static void
-+mppe_comp_reset(void *arg)
-+{
-+ struct ppp_mppe_state *state = (struct ppp_mppe_state *)arg;
-+
-+ if (state->debug)
-+ printk(KERN_DEBUG "%s%d: resetting MPPC/MPPE compressor\n",
-+ __FUNCTION__, state->unit);
-+
-+ state->nextflushed = 1;
-+ if (state->mppe)
-+ arc4_setkey(state, state->session_key, state->keylen);
-+}
-+
-+static void
-+mppe_decomp_reset(void *arg)
-+{
-+ /* When MPPC/MPPE is in use, we shouldn't receive any CCP Reset-Ack.
-+ But when we receive such a packet, we just ignore it. */
-+ return;
-+}
-+
-+static void
-+mppe_stats(void *arg, struct compstat *stats)
-+{
-+ struct ppp_mppe_state *state = (struct ppp_mppe_state *)arg;
-+
-+ *stats = state->stats;
-+}
-+
-+/***************************/
-+/**** Compression stuff ****/
-+/***************************/
-+/* inserts 1 to 8 bits into the output buffer */
-+static inline void putbits8(u8 *buf, u32 val, const u32 n, u32 *i, u32 *l)
-+{
-+ buf += *i;
-+ if (*l >= n) {
-+ *l = (*l) - n;
-+ val <<= *l;
-+ *buf = *buf | (val & 0xff);
-+ if (*l == 0) {
-+ *l = 8;
-+ (*i)++;
-+ *(++buf) = 0;
-+ }
-+ } else {
-+ (*i)++;
-+ *l = 8 - n + (*l);
-+ val <<= *l;
-+ *buf = *buf | ((val >> 8) & 0xff);
-+ *(++buf) = val & 0xff;
-+ }
-+}
-+
-+/* inserts 9 to 16 bits into the output buffer */
-+static inline void putbits16(u8 *buf, u32 val, const u32 n, u32 *i, u32 *l)
-+{
-+ buf += *i;
-+ if (*l >= n - 8) {
-+ (*i)++;
-+ *l = 8 - n + (*l);
-+ val <<= *l;
-+ *buf = *buf | ((val >> 8) & 0xff);
-+ *(++buf) = val & 0xff;
-+ if (*l == 0) {
-+ *l = 8;
-+ (*i)++;
-+ *(++buf) = 0;
-+ }
-+ } else {
-+ (*i)++; (*i)++;
-+ *l = 16 - n + (*l);
-+ val <<= *l;
-+ *buf = *buf | ((val >> 16) & 0xff);
-+ *(++buf) = (val >> 8) & 0xff;
-+ *(++buf) = val & 0xff;
-+ }
-+}
-+
-+/* inserts 17 to 24 bits into the output buffer */
-+static inline void putbits24(u8 *buf, u32 val, const u32 n, u32 *i, u32 *l)
-+{
-+ buf += *i;
-+ if (*l >= n - 16) {
-+ (*i)++; (*i)++;
-+ *l = 16 - n + (*l);
-+ val <<= *l;
-+ *buf = *buf | ((val >> 16) & 0xff);
-+ *(++buf) = (val >> 8) & 0xff;
-+ *(++buf) = val & 0xff;
-+ if (*l == 0) {
-+ *l = 8;
-+ (*i)++;
-+ *(++buf) = 0;
-+ }
-+ } else {
-+ (*i)++; (*i)++; (*i)++;
-+ *l = 24 - n + (*l);
-+ val <<= *l;
-+ *buf = *buf | ((val >> 24) & 0xff);
-+ *(++buf) = (val >> 16) & 0xff;
-+ *(++buf) = (val >> 8) & 0xff;
-+ *(++buf) = val & 0xff;
-+ }
-+}
-+
-+static int
-+mppc_compress(struct ppp_mppe_state *state, unsigned char *ibuf,
-+ unsigned char *obuf, int isize, int osize)
-+{
-+ u32 olen, off, len, idx, i, l;
-+ u8 *hist, *sbuf, *p, *q, *r, *s;
-+
-+ /*
-+ At this point, to avoid possible buffer overflow caused by packet
-+ expansion during/after compression, we should make sure that
-+ osize >= (((isize*9)/8)+1)+2, but we don't do that because in
-+ ppp_generic.c we simply allocate bigger obuf.
-+
-+ Maximum MPPC packet expansion is 12.5%. This is the worst case when
-+ all octets in the input buffer are >= 0x80 and we cannot find any
-+ repeated tokens. Additionally we have to reserve 2 bytes for MPPE/MPPC
-+ status bits and coherency counter.
-+ */
-+
-+ hist = state->hist + MPPE_HIST_LEN;
-+ /* check if there is enough room at the end of the history */
-+ if (state->histptr + isize >= 2*MPPE_HIST_LEN) {
-+ state->bits |= MPPE_BIT_RESET;
-+ state->histptr = MPPE_HIST_LEN;
-+ memcpy(state->hist, hist, MPPE_HIST_LEN);
-+ }
-+ /* add packet to the history; isize must be <= MPPE_HIST_LEN */
-+ sbuf = state->hist + state->histptr;
-+ memcpy(sbuf, ibuf, isize);
-+ state->histptr += isize;
-+
-+ /* compress data */
-+ r = sbuf + isize;
-+ *obuf = olen = i = 0;
-+ l = 8;
-+ while (i < isize - 2) {
-+ s = q = sbuf + i;
-+ idx = ((40543*((((s[0]<<4)^s[1])<<4)^s[2]))>>4) & 0x1fff;
-+ p = hist + state->hash[idx];
-+ state->hash[idx] = (u16) (s - hist);
-+ off = s - p;
-+ if (off > MPPE_HIST_LEN - 1 || off < 1 || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++) {
-+ /* no match found; encode literal byte */
-+ if (ibuf[i] < 0x80) { /* literal byte < 0x80 */
-+ putbits8(obuf, (u32) ibuf[i], 8, &olen, &l);
-+ } else { /* literal byte >= 0x80 */
-+ putbits16(obuf, (u32) (0x100|(ibuf[i]&0x7f)), 9, &olen, &l);
-+ }
-+ ++i;
-+ continue;
-+ }
-+ if (r - q >= 64) {
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
-+ *p++ != *s++;
-+ if (s - q == 64) {
-+ p--; s--;
-+ while((*p++ == *s++) && (s < r) && (p < q));
-+ }
-+ } else {
-+ while((*p++ == *s++) && (s < r) && (p < q));
-+ }
-+ len = s - q - 1;
-+ i += len;
-+
-+ /* at least 3 character match found; code data */
-+ /* encode offset */
-+ if (off < 64) { /* 10-bit offset; 0 <= offset < 64 */
-+ putbits16(obuf, 0x3c0|off, 10, &olen, &l);
-+ } else if (off < 320) { /* 12-bit offset; 64 <= offset < 320 */
-+ putbits16(obuf, 0xe00|(off-64), 12, &olen, &l);
-+ } else if (off < 8192) { /* 16-bit offset; 320 <= offset < 8192 */
-+ putbits16(obuf, 0xc000|(off-320), 16, &olen, &l);
-+ } else {
-+ /* This shouldn't happen; we return 0 what means "packet expands",
-+ and we send packet uncompressed. */
-+ if (state->debug)
-+ printk(KERN_DEBUG "%s%d: wrong offset value: %d\n",
-+ __FUNCTION__, state->unit, off);
-+ return 0;
-+ }
-+ /* encode length of match */
-+ if (len < 4) { /* length = 3 */
-+ putbits8(obuf, 0, 1, &olen, &l);
-+ } else if (len < 8) { /* 4 <= length < 8 */
-+ putbits8(obuf, 0x08|(len&0x03), 4, &olen, &l);
-+ } else if (len < 16) { /* 8 <= length < 16 */
-+ putbits8(obuf, 0x30|(len&0x07), 6, &olen, &l);
-+ } else if (len < 32) { /* 16 <= length < 32 */
-+ putbits8(obuf, 0xe0|(len&0x0f), 8, &olen, &l);
-+ } else if (len < 64) { /* 32 <= length < 64 */
-+ putbits16(obuf, 0x3c0|(len&0x1f), 10, &olen, &l);
-+ } else if (len < 128) { /* 64 <= length < 128 */
-+ putbits16(obuf, 0xf80|(len&0x3f), 12, &olen, &l);
-+ } else if (len < 256) { /* 128 <= length < 256 */
-+ putbits16(obuf, 0x3f00|(len&0x7f), 14, &olen, &l);
-+ } else if (len < 512) { /* 256 <= length < 512 */
-+ putbits16(obuf, 0xfe00|(len&0xff), 16, &olen, &l);
-+ } else if (len < 1024) { /* 512 <= length < 1024 */
-+ putbits24(obuf, 0x3fc00|(len&0x1ff), 18, &olen, &l);
-+ } else if (len < 2048) { /* 1024 <= length < 2048 */
-+ putbits24(obuf, 0xff800|(len&0x3ff), 20, &olen, &l);
-+ } else if (len < 4096) { /* 2048 <= length < 4096 */
-+ putbits24(obuf, 0x3ff000|(len&0x7ff), 22, &olen, &l);
-+ } else if (len < 8192) { /* 4096 <= length < 8192 */
-+ putbits24(obuf, 0xffe000|(len&0xfff), 24, &olen, &l);
-+ } else {
-+ /* This shouldn't happen; we return 0 what means "packet expands",
-+ and send packet uncompressed. */
-+ if (state->debug)
-+ printk(KERN_DEBUG "%s%d: wrong length of match value: %d\n",
-+ __FUNCTION__, state->unit, len);
-+ return 0;
-+ }
-+ }
-+
-+ /* Add remaining octets to the output */
-+ while(isize - i > 0) {
-+ if (ibuf[i] < 0x80) { /* literal byte < 0x80 */
-+ putbits8(obuf, (u32) ibuf[i++], 8, &olen, &l);
-+ } else { /* literal byte >= 0x80 */
-+ putbits16(obuf, (u32) (0x100|(ibuf[i++]&0x7f)), 9, &olen, &l);
-+ }
-+ }
-+ /* Reset unused bits of the last output octet */
-+ if ((l != 0) && (l != 8)) {
-+ putbits8(obuf, 0, l, &olen, &l);
-+ }
-+
-+ return (int) olen;
-+}
-+
-+int
-+mppe_compress(void *arg, unsigned char *ibuf, unsigned char *obuf,
-+ int isize, int osize)
-+{
-+ struct ppp_mppe_state *state = (struct ppp_mppe_state *) arg;
-+ int proto, olen, complen, off;
-+ unsigned char *wptr;
-+
-+ /* Check that the protocol is in the range we handle. */
-+ proto = PPP_PROTOCOL(ibuf);
-+ if (proto < 0x0021 || proto > 0x00fa)
-+ return 0;
-+
-+ wptr = obuf;
-+ /* Copy over the PPP header */
-+ wptr[0] = PPP_ADDRESS(ibuf);
-+ wptr[1] = PPP_CONTROL(ibuf);
-+ wptr[2] = PPP_COMP >> 8;
-+ wptr[3] = PPP_COMP;
-+ wptr += PPP_HDRLEN + (MPPE_OVHD / 2); /* Leave two octets for MPPE/MPPC bits */
-+
-+ /*
-+ * In ver. 0.99 protocol field was compressed. Deflate and BSD compress
-+ * do PFC before actual compression, RCF2118 and RFC3078 are not precise
-+ * on this topic so I decided to do PFC. Unfortunately this change caused
-+ * incompatibility with older/other MPPE/MPPC modules. I have received
-+ * a lot of complaints from unexperienced users so I have decided to revert
-+ * to previous state, i.e. the protocol field is sent uncompressed now.
-+ * Although this may be changed in the future.
-+ *
-+ * Receiving side (mppe_decompress()) still accepts packets with compressed
-+ * and uncompressed protocol field so you shouldn't get "Unsupported protocol
-+ * 0x2145 received" messages anymore.
-+ */
-+ //off = (proto > 0xff) ? 2 : 3; /* PFC - skip first protocol byte if 0 */
-+ off = 2;
-+
-+ ibuf += off;
-+
-+ mppe_increase_ccount(state);
-+
-+ if (state->nextflushed) {
-+ state->bits |= MPPE_BIT_FLUSHED;
-+ state->nextflushed = 0;
-+ if (state->mppe && !state->stateless) {
-+ /*
-+ * If this is the flag packet, the key has been already changed in
-+ * mppe_increase_ccount() so we dont't do it once again.
-+ */
-+ if ((state->ccount & 0xff) != 0xff) {
-+ arc4_setkey(state, state->session_key, state->keylen);
-+ }
-+ }
-+ if (state->mppc) { /* reset history */
-+ state->bits |= MPPE_BIT_RESET;
-+ state->histptr = MPPE_HIST_LEN;
-+ memset(state->hist + MPPE_HIST_LEN, 0, MPPE_HIST_LEN*sizeof(u8));
-+ }
-+ }
-+
-+ if (state->mppc && !state->mppe) { /* Do only compression */
-+ complen = mppc_compress(state, ibuf, wptr, isize - off,
-+ osize - PPP_HDRLEN - (MPPE_OVHD / 2));
-+ /*
-+ * TODO: Implement an heuristics to handle packet expansion in a smart
-+ * way. Now, when a packet expands, we send it as uncompressed and
-+ * when next packet is sent we have to reset compressor's history.
-+ * Maybe it would be better to send such packet as compressed in order
-+ * to keep history's continuity.
-+ */
-+ if ((complen > isize) || (complen > osize - PPP_HDRLEN) ||
-+ (complen == 0)) {
-+ /* packet expands */
-+ state->nextflushed = 1;
-+ memcpy(wptr, ibuf, isize - off);
-+ olen = isize - (off - 2) + MPPE_OVHD;
-+ (state->stats).inc_bytes += olen;
-+ (state->stats).inc_packets++;
-+ } else {
-+ state->bits |= MPPE_BIT_COMP;
-+ olen = complen + PPP_HDRLEN + (MPPE_OVHD / 2);
-+ (state->stats).comp_bytes += olen;
-+ (state->stats).comp_packets++;
-+ }
-+ } else { /* Do encryption with or without compression */
-+ state->bits |= MPPE_BIT_ENCRYPTED;
-+ if (!state->mppc && state->mppe) { /* Do only encryption */
-+ /* read from ibuf, write to wptr, adjust for PPP_HDRLEN */
-+ arc4_encrypt(state, ibuf, isize - off, wptr);
-+ olen = isize - (off - 2) + MPPE_OVHD;
-+ (state->stats).inc_bytes += olen;
-+ (state->stats).inc_packets++;
-+ } else { /* Do compression and then encryption - RFC3078 */
-+ complen = mppc_compress(state, ibuf, wptr, isize - off,
-+ osize - PPP_HDRLEN - (MPPE_OVHD / 2));
-+ /*
-+ * TODO: Implement an heuristics to handle packet expansion in a smart
-+ * way. Now, when a packet expands, we send it as uncompressed and
-+ * when next packet is sent we have to reset compressor's history.
-+ * Maybe it would be good to send such packet as compressed in order
-+ * to keep history's continuity.
-+ */
-+ if ((complen > isize) || (complen > osize - PPP_HDRLEN) ||
-+ (complen == 0)) {
-+ /* packet expands */
-+ state->nextflushed = 1;
-+ arc4_encrypt(state, ibuf, isize - off, wptr);
-+ olen = isize - (off - 2) + MPPE_OVHD;
-+ (state->stats).inc_bytes += olen;
-+ (state->stats).inc_packets++;
-+ } else {
-+ state->bits |= MPPE_BIT_COMP;
-+ /* Hack warning !!! RC4 implementation which we use does
-+ encryption "in place" - it means that input and output
-+ buffers can be *the same* memory area. Therefore we don't
-+ need to use a temporary buffer. But be careful - other
-+ implementations don't have to be so nice.
-+ I used to use ibuf as temporary buffer here, but it led
-+ packet sniffers into error. Thanks to Wilfried Weissmann
-+ for pointing that. */
-+ arc4_encrypt(state, wptr, complen, wptr);
-+ olen = complen + PPP_HDRLEN + (MPPE_OVHD / 2);
-+ (state->stats).comp_bytes += olen;
-+ (state->stats).comp_packets++;
-+ }
-+ }
-+ }
-+
-+ /* write status bits and coherency counter into the output buffer */
-+ wptr = obuf + PPP_HDRLEN;
-+ wptr[0] = MPPE_CTRLHI(state);
-+ wptr[1] = MPPE_CTRLLO(state);
-+
-+ state->bits = 0;
-+
-+ (state->stats).unc_bytes += isize;
-+ (state->stats).unc_packets++;
-+
-+ return olen;
-+}
-+
-+/***************************/
-+/*** Decompression stuff ***/
-+/***************************/
-+static inline u32 getbits(const u8 *buf, const u32 n, u32 *i, u32 *l)
-+{
-+ static const u32 m[] = {0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff};
-+ u32 res, ol;
-+
-+ ol = *l;
-+ if (*l >= n) {
-+ *l = (*l) - n;
-+ res = (buf[*i] & m[ol]) >> (*l);
-+ if (*l == 0) {
-+ *l = 8;
-+ (*i)++;
-+ }
-+ } else {
-+ *l = 8 - n + (*l);
-+ res = (buf[(*i)++] & m[ol]) << 8;
-+ res = (res | buf[*i]) >> (*l);
-+ }
-+
-+ return res;
-+}
-+
-+static inline u32 getbyte(const u8 *buf, const u32 i, const u32 l)
-+{
-+ if (l == 8) {
-+ return buf[i];
-+ } else {
-+ return (((buf[i] << 8) | buf[i+1]) >> l) & 0xff;
-+ }
-+}
-+
-+static inline void lamecopy(u8 *dst, u8 *src, u32 len)
-+{
-+ while (len--)
-+ *dst++ = *src++;
-+}
-+
-+static int
-+mppc_decompress(struct ppp_mppe_state *state, unsigned char *ibuf,
-+ unsigned char *obuf, int isize, int osize)
-+{
-+ u32 olen, off, len, bits, val, sig, i, l;
-+ u8 *history, *s;
-+
-+ history = state->hist + state->histptr;
-+ olen = len = i = 0;
-+ l = 8;
-+ bits = isize * 8;
-+ while (bits >= 8) {
-+ val = getbyte(ibuf, i++, l);
-+ if (val < 0x80) { /* literal byte < 0x80 */
-+ if (state->histptr < 2*MPPE_HIST_LEN) {
-+ /* copy uncompressed byte to the history */
-+ (state->hist)[(state->histptr)++] = (u8) val;
-+ } else {
-+ /* buffer overflow; drop packet */
-+ if (state->debug)
-+ printk(KERN_ERR "%s%d: trying to write outside history "
-+ "buffer\n", __FUNCTION__, state->unit);
-+ return DECOMP_ERROR;
-+ }
-+ olen++;
-+ bits -= 8;
-+ continue;
-+ }
-+
-+ sig = val & 0xc0;
-+ if (sig == 0x80) { /* literal byte >= 0x80 */
-+ if (state->histptr < 2*MPPE_HIST_LEN) {
-+ /* copy uncompressed byte to the history */
-+ (state->hist)[(state->histptr)++] =
-+ (u8) (0x80|((val&0x3f)<<1)|getbits(ibuf, 1 , &i ,&l));
-+ } else {
-+ /* buffer overflow; drop packet */
-+ if (state->debug)
-+ printk(KERN_ERR "%s%d: trying to write outside history "
-+ "buffer\n", __FUNCTION__, state->unit);
-+ return DECOMP_ERROR;
-+ }
-+ olen++;
-+ bits -= 9;
-+ continue;
-+ }
-+
-+ /* Not a literal byte so it must be an (offset,length) pair */
-+ /* decode offset */
-+ sig = val & 0xf0;
-+ if (sig == 0xf0) { /* 10-bit offset; 0 <= offset < 64 */
-+ off = (((val&0x0f)<<2)|getbits(ibuf, 2 , &i ,&l));
-+ bits -= 10;
-+ } else {
-+ if (sig == 0xe0) { /* 12-bit offset; 64 <= offset < 320 */
-+ off = ((((val&0x0f)<<4)|getbits(ibuf, 4 , &i ,&l))+64);
-+ bits -= 12;
-+ } else {
-+ if ((sig&0xe0) == 0xc0) {/* 16-bit offset; 320 <= offset < 8192 */
-+ off = ((((val&0x1f)<<8)|getbyte(ibuf, i++, l))+320);
-+ bits -= 16;
-+ if (off > MPPE_HIST_LEN - 1) {
-+ if (state->debug)
-+ printk(KERN_DEBUG "%s%d: too big offset value: %d\n",
-+ __FUNCTION__, state->unit, off);
-+ return DECOMP_ERROR;
-+ }
-+ } else { /* this shouldn't happen */
-+ if (state->debug)
-+ printk(KERN_DEBUG "%s%d: cannot decode offset value\n",
-+ __FUNCTION__, state->unit);
-+ return DECOMP_ERROR;
-+ }
-+ }
-+ }
-+ /* decode length of match */
-+ val = getbyte(ibuf, i, l);
-+ if ((val & 0x80) == 0x00) { /* len = 3 */
-+ len = 3;
-+ bits--;
-+ getbits(ibuf, 1 , &i ,&l);
-+ } else if ((val & 0xc0) == 0x80) { /* 4 <= len < 8 */
-+ len = 0x04 | ((val>>4) & 0x03);
-+ bits -= 4;
-+ getbits(ibuf, 4 , &i ,&l);
-+ } else if ((val & 0xe0) == 0xc0) { /* 8 <= len < 16 */
-+ len = 0x08 | ((val>>2) & 0x07);
-+ bits -= 6;
-+ getbits(ibuf, 6 , &i ,&l);
-+ } else if ((val & 0xf0) == 0xe0) { /* 16 <= len < 32 */
-+ len = 0x10 | (val & 0x0f);
-+ bits -= 8;
-+ i++;
-+ } else {
-+ bits -= 8;
-+ val = (val << 8) | getbyte(ibuf, ++i, l);
-+ if ((val & 0xf800) == 0xf000) { /* 32 <= len < 64 */
-+ len = 0x0020 | ((val >> 6) & 0x001f);
-+ bits -= 2;
-+ getbits(ibuf, 2 , &i ,&l);
-+ } else if ((val & 0xfc00) == 0xf800) { /* 64 <= len < 128 */
-+ len = 0x0040 | ((val >> 4) & 0x003f);
-+ bits -= 4;
-+ getbits(ibuf, 4 , &i ,&l);
-+ } else if ((val & 0xfe00) == 0xfc00) { /* 128 <= len < 256 */
-+ len = 0x0080 | ((val >> 2) & 0x007f);
-+ bits -= 6;
-+ getbits(ibuf, 6 , &i ,&l);
-+ } else if ((val & 0xff00) == 0xfe00) { /* 256 <= len < 512 */
-+ len = 0x0100 | (val & 0x00ff);
-+ bits -= 8;
-+ i++;
-+ } else {
-+ bits -= 8;
-+ val = (val << 8) | getbyte(ibuf, ++i, l);
-+ if ((val & 0xff8000) == 0xff0000) { /* 512 <= len < 1024 */
-+ len = 0x000200 | ((val >> 6) & 0x0001ff);
-+ bits -= 2;
-+ getbits(ibuf, 2 , &i ,&l);
-+ } else if ((val & 0xffc000) == 0xff8000) {/* 1024 <= len < 2048 */
-+ len = 0x000400 | ((val >> 4) & 0x0003ff);
-+ bits -= 4;
-+ getbits(ibuf, 4 , &i ,&l);
-+ } else if ((val & 0xffe000) == 0xffc000) {/* 2048 <= len < 4096 */
-+ len = 0x000800 | ((val >> 2) & 0x0007ff);
-+ bits -= 6;
-+ getbits(ibuf, 6 , &i ,&l);
-+ } else if ((val & 0xfff000) == 0xffe000) {/* 4096 <= len < 8192 */
-+ len = 0x001000 | (val & 0x000fff);
-+ bits -= 8;
-+ i++;
-+ } else { /* this shouldn't happen */
-+ if (state->debug)
-+ printk(KERN_DEBUG "%s%d: wrong length code: 0x%X\n",
-+ __FUNCTION__, state->unit, val);
-+ return DECOMP_ERROR;
-+ }
-+ }
-+ }
-+ s = state->hist + state->histptr;
-+ state->histptr += len;
-+ olen += len;
-+ if (state->histptr < 2*MPPE_HIST_LEN) {
-+ /* copy uncompressed bytes to the history */
-+
-+ /* In some cases len may be greater than off. It means that memory
-+ * areas pointed by s and s-off overlap. I had used memmove() here
-+ * because I thought that it acts as libc's version. Unfortunately,
-+ * I was wrong. :-) I got strange errors sometimes. Wilfried suggested
-+ * using of byte by byte copying here and strange errors disappeared.
-+ */
-+ lamecopy(s, s - off, len);
-+ } else {
-+ /* buffer overflow; drop packet */
-+ if (state->debug)
-+ printk(KERN_ERR "%s%d: trying to write outside history "
-+ "buffer\n", __FUNCTION__, state->unit);
-+ return DECOMP_ERROR;
-+ }
-+ }
-+
-+ /* Do PFC decompression */
-+ len = olen;
-+ if ((history[0] & 0x01) != 0) {
-+ obuf[0] = 0;
-+ obuf++;
-+ len++;
-+ }
-+
-+ if (len <= osize) {
-+ /* copy uncompressed packet to the output buffer */
-+ memcpy(obuf, history, olen);
-+ } else {
-+ /* buffer overflow; drop packet */
-+ if (state->debug)
-+ printk(KERN_ERR "%s%d: too big uncompressed packet: %d\n",
-+ __FUNCTION__, state->unit, len + (PPP_HDRLEN / 2));
-+ return DECOMP_ERROR;
-+ }
-+
-+ return (int) len;
-+}
-+
-+int
-+mppe_decompress(void *arg, unsigned char *ibuf, int isize,
-+ unsigned char *obuf, int osize)
-+{
-+ struct ppp_mppe_state *state = (struct ppp_mppe_state *)arg;
-+ int seq, bits, uncomplen;
-+
-+ if (isize <= PPP_HDRLEN + MPPE_OVHD) {
-+ if (state->debug) {
-+ printk(KERN_DEBUG "%s%d: short packet (len=%d)\n", __FUNCTION__,
-+ state->unit, isize);
-+ }
-+ return DECOMP_ERROR;
-+ }
-+
-+ /* Get coherency counter and control bits from input buffer */
-+ seq = MPPE_CCOUNT(ibuf);
-+ bits = MPPE_BITS(ibuf);
-+
-+ if (state->stateless) {
-+ /* RFC 3078, sec 8.1. */
-+ mppe_increase_ccount(state);
-+ if ((seq != state->ccount) && state->debug)
-+ printk(KERN_DEBUG "%s%d: bad sequence number: %d, expected: %d\n",
-+ __FUNCTION__, state->unit, seq, state->ccount);
-+ while (seq != state->ccount)
-+ mppe_increase_ccount(state);
-+ } else {
-+ /* RFC 3078, sec 8.2. */
-+ if (state->flushexpected) { /* discard state */
-+ if ((bits & MPPE_BIT_FLUSHED)) { /* we received expected FLUSH bit */
-+ while (seq != state->ccount)
-+ mppe_increase_ccount(state);
-+ state->flushexpected = 0;
-+ } else /* drop packet*/
-+ return DECOMP_ERROR;
-+ } else { /* normal state */
-+ mppe_increase_ccount(state);
-+ if (seq != state->ccount) {
-+ /* Packet loss detected, enter the discard state. */
-+ if (state->debug)
-+ printk(KERN_DEBUG "%s%d: bad sequence number: %d, expected: %d\n",
-+ __FUNCTION__, state->unit, seq, state->ccount);
-+ state->flushexpected = 1;
-+ return DECOMP_ERROR;
-+ }
-+ }
-+ if (state->mppe && (bits & MPPE_BIT_FLUSHED)) {
-+ arc4_setkey(state, state->session_key, state->keylen);
-+ }
-+ }
-+
-+ if (state->mppc && (bits & (MPPE_BIT_FLUSHED | MPPE_BIT_RESET))) {
-+ state->histptr = MPPE_HIST_LEN;
-+ if ((bits & MPPE_BIT_FLUSHED)) {
-+ memset(state->hist + MPPE_HIST_LEN, 0, MPPE_HIST_LEN*sizeof(u8));
-+ } else
-+ if ((bits & MPPE_BIT_RESET)) {
-+ memcpy(state->hist, state->hist + MPPE_HIST_LEN, MPPE_HIST_LEN);
-+ }
-+ }
-+
-+ /* Fill in the first part of the PPP header. The protocol field
-+ comes from the decompressed data. */
-+ obuf[0] = PPP_ADDRESS(ibuf);
-+ obuf[1] = PPP_CONTROL(ibuf);
-+ obuf += PPP_HDRLEN / 2;
-+
-+ if (state->mppe) { /* process encrypted packet */
-+ if ((bits & MPPE_BIT_ENCRYPTED)) {
-+ /* OK, packet encrypted, so decrypt it */
-+ if (state->mppc && (bits & MPPE_BIT_COMP)) {
-+ /* Hack warning !!! RC4 implementation which we use does
-+ decryption "in place" - it means that input and output
-+ buffers can be *the same* memory area. Therefore we don't
-+ need to use a temporary buffer. But be careful - other
-+ implementations don't have to be so nice. */
-+ arc4_decrypt(state, ibuf + PPP_HDRLEN + (MPPE_OVHD / 2), isize -
-+ PPP_HDRLEN - (MPPE_OVHD / 2), ibuf + PPP_HDRLEN +
-+ (MPPE_OVHD / 2));
-+ uncomplen = mppc_decompress(state, ibuf + PPP_HDRLEN +
-+ (MPPE_OVHD / 2), obuf, isize -
-+ PPP_HDRLEN - (MPPE_OVHD / 2),
-+ osize - (PPP_HDRLEN / 2));
-+ if (uncomplen == DECOMP_ERROR) {
-+ state->flushexpected = 1;
-+ return DECOMP_ERROR;
-+ }
-+ uncomplen += PPP_HDRLEN / 2;
-+ (state->stats).comp_bytes += isize;
-+ (state->stats).comp_packets++;
-+ } else {
-+ uncomplen = isize - MPPE_OVHD;
-+ /* Decrypt the first byte in order to check if it is
-+ compressed or uncompressed protocol field */
-+ arc4_decrypt(state, ibuf + PPP_HDRLEN + (MPPE_OVHD / 2), 1, obuf);
-+ /* Do PFC decompression */
-+ if ((obuf[0] & 0x01) != 0) {
-+ obuf[1] = obuf[0];
-+ obuf[0] = 0;
-+ obuf++;
-+ uncomplen++;
-+ }
-+ /* And finally, decrypt the rest of the frame. */
-+ arc4_decrypt(state, ibuf + PPP_HDRLEN + (MPPE_OVHD / 2) + 1,
-+ isize - PPP_HDRLEN - (MPPE_OVHD / 2) - 1, obuf + 1);
-+ (state->stats).inc_bytes += isize;
-+ (state->stats).inc_packets++;
-+ }
-+ } else { /* this shouldn't happen */
-+ if (state->debug)
-+ printk(KERN_ERR "%s%d: encryption negotiated but not an "
-+ "encrypted packet received\n", __FUNCTION__, state->unit);
-+ mppe_change_key(state, 0);
-+ state->flushexpected = 1;
-+ return DECOMP_ERROR;
-+ }
-+ } else {
-+ if (state->mppc) { /* no MPPE, only MPPC */
-+ if ((bits & MPPE_BIT_COMP)) {
-+ uncomplen = mppc_decompress(state, ibuf + PPP_HDRLEN +
-+ (MPPE_OVHD / 2), obuf, isize -
-+ PPP_HDRLEN - (MPPE_OVHD / 2),
-+ osize - (PPP_HDRLEN / 2));
-+ if (uncomplen == DECOMP_ERROR) {
-+ state->flushexpected = 1;
-+ return DECOMP_ERROR;
-+ }
-+ uncomplen += PPP_HDRLEN / 2;
-+ (state->stats).comp_bytes += isize;
-+ (state->stats).comp_packets++;
-+ } else {
-+ memcpy(obuf, ibuf + PPP_HDRLEN + (MPPE_OVHD / 2), isize -
-+ PPP_HDRLEN - (MPPE_OVHD / 2));
-+ uncomplen = isize - MPPE_OVHD;
-+ (state->stats).inc_bytes += isize;
-+ (state->stats).inc_packets++;
-+ }
-+ } else { /* this shouldn't happen */
-+ if (state->debug)
-+ printk(KERN_ERR "%s%d: error - not an MPPC or MPPE frame "
-+ "received\n", __FUNCTION__, state->unit);
-+ state->flushexpected = 1;
-+ return DECOMP_ERROR;
-+ }
-+ }
-+
-+ (state->stats).unc_bytes += uncomplen;
-+ (state->stats).unc_packets++;
-+
-+ return uncomplen;
-+}
-+
-+
-+/************************************************************
-+ * Module interface table
-+ ************************************************************/
-+
-+/* These are in ppp_generic.c */
-+extern int ppp_register_compressor (struct compressor *cp);
-+extern void ppp_unregister_compressor (struct compressor *cp);
-+
-+/*
-+ * Functions exported to ppp_generic.c.
-+ *
-+ * In case of MPPC/MPPE there is no need to process incompressible data
-+ * because such a data is sent in MPPC/MPPE frame. Therefore the (*incomp)
-+ * callback function isn't needed.
-+ */
-+struct compressor ppp_mppe = {
-+ CI_MPPE, /* compress_proto */
-+ mppe_comp_alloc, /* comp_alloc */
-+ mppe_comp_free, /* comp_free */
-+ mppe_comp_init, /* comp_init */
-+ mppe_comp_reset, /* comp_reset */
-+ mppe_compress, /* compress */
-+ mppe_stats, /* comp_stat */
-+ mppe_decomp_alloc, /* decomp_alloc */
-+ mppe_comp_free, /* decomp_free */
-+ mppe_decomp_init, /* decomp_init */
-+ mppe_decomp_reset, /* decomp_reset */
-+ mppe_decompress, /* decompress */
-+ NULL, /* incomp */
-+ mppe_stats, /* decomp_stat */
-+};
-+
-+/************************************************************
-+ * Module support routines
-+ ************************************************************/
-+
-+int __init mppe_module_init(void)
-+{
-+ int answer;
-+
-+ /* When the module is compiled into kernel, it is initialized before
-+ * CryptoAPI. Therefore the code below reports that there is no crypto
-+ * stuff in the kernel. Marlon de Boer who has pointed out the problem,
-+ * has sent also a message to CryptoAPI developers, so maybe in the future
-+ * the code will be uncommented.
-+ *
-+ if (!(crypto_alg_available("arc4", 0) && crypto_alg_available("sha1", 0))) {
-+ printk(KERN_ERR "Kernel doesn't provide ARC4 and/or SHA1 algorithms "
-+ "required by MPPE/MPPC. Check CryptoAPI configuration.\n");
-+ return -ENODEV;
-+ }
-+ */
-+
-+ /* Allocate space for SHAPad1, SHAPad2 and ... */
-+ sha_pad = kmalloc(sizeof(struct sha_pad), GFP_KERNEL);
-+ if (sha_pad == NULL)
-+ return -ENOMEM;
-+ /* ... initialize them */
-+ memset(sha_pad->sha_pad1, 0x00, sizeof(sha_pad->sha_pad1));
-+ memset(sha_pad->sha_pad2, 0xf2, sizeof(sha_pad->sha_pad2));
-+
-+ answer = ppp_register_compressor(&ppp_mppe);
-+ if (answer == 0) {
-+ printk(KERN_INFO "MPPE/MPPC encryption/compression module registered\n");
-+ }
-+ return answer;
-+}
-+
-+void __exit mppe_module_cleanup(void)
-+{
-+ kfree(sha_pad);
-+ ppp_unregister_compressor(&ppp_mppe);
-+ printk(KERN_INFO "MPPE/MPPC encryption/compression module unregistered\n");
-+}
-+
-+module_init(mppe_module_init);
-+module_exit(mppe_module_cleanup);
-+
-+MODULE_AUTHOR("Jan Dubiec <jdx@slackware.pl>");
-+MODULE_DESCRIPTION("MPPE/MPPC encryption/compression module for Linux");
-+MODULE_LICENSE("Dual BSD/GPL");
---- a/include/linux/ppp-comp.h
-+++ b/include/linux/ppp-comp.h
-@@ -28,7 +28,7 @@
- */
-
- /*
-- * ==FILEVERSION 980319==
-+ * ==FILEVERSION 20040509==
- *
- * NOTE TO MAINTAINERS:
- * If you modify this file at all, please set the above date.
-@@ -78,7 +78,7 @@ struct compressor {
-
- /* Compress a packet */
- int (*compress) (void *state, unsigned char *rptr,
-- unsigned char *obuf, int isize, int osize);
-+ unsigned char *obuf, int isize, int osize);
-
- /* Return compression statistics */
- void (*comp_stat) (void *state, struct compstat *stats);
-@@ -99,7 +99,7 @@ struct compressor {
-
- /* Decompress a packet. */
- int (*decompress) (void *state, unsigned char *ibuf, int isize,
-- unsigned char *obuf, int osize);
-+ unsigned char *obuf, int osize);
-
- /* Update state for an incompressible packet received */
- void (*incomp) (void *state, unsigned char *ibuf, int icnt);
-@@ -187,6 +187,42 @@ struct compressor {
- #define DEFLATE_CHK_SEQUENCE 0
-
- /*
-+ * Definitions for MPPE/MPPC.
-+ */
-+
-+#define CI_MPPE 18 /* config option for MPPE */
-+#define CILEN_MPPE 6 /* length of config option */
-+
-+#define MPPE_OVHD 4 /* MPPE overhead */
-+#define MPPE_MAX_KEY_LEN 16 /* largest key length (128-bit) */
-+
-+#define MPPE_STATELESS 0x01 /* configuration bit H */
-+#define MPPE_40BIT 0x20 /* configuration bit L */
-+#define MPPE_56BIT 0x80 /* configuration bit M */
-+#define MPPE_128BIT 0x40 /* configuration bit S */
-+#define MPPE_MPPC 0x01 /* configuration bit C */
-+
-+/*
-+ * Definitions for Stac LZS.
-+ */
-+
-+#define CI_LZS 17 /* config option for Stac LZS */
-+#define CILEN_LZS 5 /* length of config option */
-+
-+#define LZS_OVHD 4 /* max. LZS overhead */
-+#define LZS_HIST_LEN 2048 /* LZS history size */
-+#define LZS_MAX_CCOUNT 0x0FFF /* max. coherency counter value */
-+
-+#define LZS_MODE_NONE 0
-+#define LZS_MODE_LCB 1
-+#define LZS_MODE_CRC 2
-+#define LZS_MODE_SEQ 3
-+#define LZS_MODE_EXT 4
-+
-+#define LZS_EXT_BIT_FLUSHED 0x80 /* bit A */
-+#define LZS_EXT_BIT_COMP 0x20 /* bit C */
-+
-+/*
- * Definitions for other, as yet unsupported, compression methods.
- */
-