# # Patch managed by http://www.mn-logistik.de/unsupported/pxa250/patcher # --- linux-2.4.20/drivers/net/Config.in~150-mppe-mppc-0.98 2005-01-07 02:52:47.191946000 -0500 +++ linux-2.4.20/drivers/net/Config.in 2005-01-07 02:57:48.408155016 -0500 @@ -288,6 +288,7 @@ 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 $CONFIG_PPP if [ "$CONFIG_EXPERIMENTAL" = "y" ]; then dep_tristate ' PPP over Ethernet (EXPERIMENTAL)' CONFIG_PPPOE $CONFIG_PPP fi --- linux-2.4.20/drivers/net/Makefile~150-mppe-mppc-0.98 2005-01-07 02:54:46.352831000 -0500 +++ linux-2.4.20/drivers/net/Makefile 2005-01-07 02:57:48.409154864 -0500 @@ -18,8 +18,9 @@ export-objs := 8390.o arlan.o aironet4500_core.o aironet4500_card.o \ ppp_async.o ppp_generic.o slhc.o pppox.o auto_irq.o \ net_init.o mii.o -list-multi := rcpci.o +list-multi := rcpci.o ppp_mppe_mppc.o rcpci-objs := rcpci45.o rclanmtl.o +ppp_mppe_c-objs := ppp_mppe_mppc_comp.o ppp_mppe_crypto.o # subdir-m += mac subdir-m += diag @@ -159,6 +160,15 @@ obj-$(CONFIG_PPP_SYNC_TTY) += ppp_synctty.o obj-$(CONFIG_PPP_DEFLATE) += ppp_deflate.o obj-$(CONFIG_PPP_BSDCOMP) += bsd_comp.o + +ifeq ($(CONFIG_PPP_MPPE),y) + obj-y += $(ppp_mppe_c-objs) +else + ifeq ($(CONFIG_PPP_MPPE),m) + obj-m += ppp_mppe_mppc.o + endif +endif + obj-$(CONFIG_PPPOE) += pppox.o pppoe.o obj-$(CONFIG_SLIP) += slip.o @@ -291,3 +301,5 @@ rcpci.o: $(rcpci-objs) $(LD) -r -o $@ $(rcpci-objs) +ppp_mppe_mppc.o: $(ppp_mppe_c-objs) + $(LD) -r -o $@ $(ppp_mppe_c-objs) --- linux-2.4.20/drivers/net/ppp_generic.c~150-mppe-mppc-0.98 2002-11-28 18:53:14.000000000 -0500 +++ linux-2.4.20/drivers/net/ppp_generic.c 2005-01-07 02:57:48.414154104 -0500 @@ -19,7 +19,7 @@ * PPP driver, written by Michael Callahan and Al Longyear, and * subsequently hacked by Paul Mackerras. * - * ==FILEVERSION 20020217== + * ==FILEVERSION 20030706== */ #include @@ -102,6 +102,7 @@ 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 */ @@ -129,6 +130,7 @@ struct sock_fprog pass_filter; /* filter for packets to pass */ struct sock_fprog active_filter;/* filter for pkts to reset idle */ #endif /* CONFIG_PPP_FILTER */ + int xpad; /* ECP or CCP (MPPE) transmit padding */ }; /* @@ -552,7 +554,9 @@ 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; @@ -1024,14 +1028,35 @@ case PPP_CCP: /* peek at outbound CCP frames */ ppp_ccp_peek(ppp, skb, 0); + /* + * When LZS or MPPE/MPPC is 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 about 12.5% bigger + than MTU */ + if (ppp->xcomp->compress_proto == CI_MPPE) + comp_ovhd = (((ppp->dev->mtu * 9) / 8) + 1); + 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 + + ppp->xpad + comp_ovhd, GFP_ATOMIC); if (new_skb == 0) { printk(KERN_ERR "PPP: no memory (comp pkt)\n"); goto drop; @@ -1043,15 +1068,28 @@ /* compressor still expects A/C bytes in hdr */ len = ppp->xcomp->compress(ppp->xc_state, skb->data - 2, new_skb->data, skb->len + 2, - ppp->dev->mtu + PPP_HDRLEN); + ppp->dev->mtu + ppp->xpad + + PPP_HDRLEN); if (len > 0 && (ppp->flags & SC_CCP_UP)) { kfree_skb(skb); 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; } } @@ -1539,14 +1577,15 @@ 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. */ @@ -1572,7 +1611,12 @@ 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; } @@ -1981,6 +2025,20 @@ ocomp->comp_free(ostate); err = 0; } + if (ccp_option[0] == CI_MPPE) + /* + * pppd (userland) has reduced the MTU by MPPE_PAD, + * to accomodate "compressor" growth. We must + * increase the space allocated for compressor + * output in ppp_send_frame() accordingly. Note + * that from a purist's view, it may be more correct + * to require multilink and fragment large packets, + * but that seems inefficient compared to this + * little trick. + */ + ppp->xpad = MPPE_PAD; + else + ppp->xpad = 0; } else { state = cp->decomp_alloc(ccp_option, data.length); @@ -2252,6 +2310,7 @@ /* 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 2004-04-06 13:56:48.000000000 -0400 +++ linux-2.4.20/drivers/net/ppp_mppe_crypto.c 2005-01-07 02:57:48.414154104 -0500 @@ -0,0 +1,257 @@ +/* + * ppp_mppe_crypto.c - cryptografic funtions for MPPE + * + * This code is Public Domain. Please see comments below. + * + * I have just put SHA1 and ARCFOUR implementations into one file + * in order to not pollute kernel namespace. + * + * Jan Dubiec , 2003-07-08 + */ + +/* + * ftp://ftp.funet.fi/pub/crypt/hash/sha/sha1.c + * + * SHA-1 in C + * By Steve Reid + * 100% Public Domain + * + * Test Vectors (from FIPS PUB 180-1) + * "abc" + * A9993E36 4706816A BA3E2571 7850C26C 9CD0D89D + * "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq" + * 84983E44 1C3BD26E BAAE4AA1 F95129E5 E54670F1 + * A million repetitions of "a" + * 34AA973C D4C4DAA4 F61EEB2B DBAD2731 6534016F + */ + +/* #define SHA1HANDSOFF * Copies data before messing with it. */ + +#if defined(__linux__) +#include +#include +#elif defined(__solaris__) +#include +#include +#include +#define memcpy(d, s, c) bcopy(s, d, c) +#define memset(d, b, c) bzero(d, c) +#endif + +#include "ppp_mppe_crypto.h" + +static void SHA1_Transform(unsigned long[5], const unsigned char[64]); + +#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits)))) + +/* blk0() and blk() perform the initial expand. */ +/* I got the idea of expanding during the round function from SSLeay */ +#if defined(__LITTLE_ENDIAN) || defined(_LITTLE_ENDIAN) +#define blk0(i) (block->l[i] = (rol(block->l[i],24)&0xFF00FF00) \ + |(rol(block->l[i],8)&0x00FF00FF)) +#elif defined(__BIG_ENDIAN) || defined(_BIG_ENDIAN) +#define blk0(i) block->l[i] +#else +#error Endianness not defined +#endif +#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \ + ^block->l[(i+2)&15]^block->l[i&15],1)) + +/* (R0+R1), R2, R3, R4 are the different operations used in SHA1 */ +#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(i)+0x5A827999+rol(v,5);w=rol(w,30); +#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30); +#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30); +#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30); +#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30); + +/* Hash a single 512-bit block. This is the core of the algorithm. */ +static void +SHA1_Transform(unsigned long state[5], const unsigned char buffer[64]) +{ + unsigned long a, b, c, d, e; + typedef union { + unsigned char c[64]; + unsigned long l[16]; + } CHAR64LONG16; + CHAR64LONG16 *block; + +#ifdef SHA1HANDSOFF + static unsigned char workspace[64]; + block = (CHAR64LONG16 *) workspace; + memcpy(block, buffer, 64); +#else + block = (CHAR64LONG16 *) buffer; +#endif + /* Copy context->state[] to working vars */ + a = state[0]; + b = state[1]; + c = state[2]; + d = state[3]; + e = state[4]; + /* 4 rounds of 20 operations each. Loop unrolled. */ + R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3); + R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7); + R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11); + R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15); + R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19); + R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23); + R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27); + R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31); + R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35); + R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39); + R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43); + R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47); + R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51); + R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55); + R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59); + R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63); + R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67); + R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71); + R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75); + R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79); + /* Add the working vars back into context.state[] */ + state[0] += a; + state[1] += b; + state[2] += c; + state[3] += d; + state[4] += e; + /* Wipe variables */ + a = b = c = d = e = 0; +} + +/* SHA1Init - Initialize new context */ +void +SHA1_Init(SHA1_CTX *context) +{ + /* SHA1 initialization constants */ + context->state[0] = 0x67452301; + context->state[1] = 0xEFCDAB89; + context->state[2] = 0x98BADCFE; + context->state[3] = 0x10325476; + context->state[4] = 0xC3D2E1F0; + context->count[0] = context->count[1] = 0; +} + +/* Run your data through this. */ +void +SHA1_Update(SHA1_CTX *context, const unsigned char *data, unsigned int len) +{ + unsigned int i, j; + + j = (context->count[0] >> 3) & 63; + if ((context->count[0] += len << 3) < (len << 3)) context->count[1]++; + context->count[1] += (len >> 29); + if ((j + len) > 63) { + memcpy(&context->buffer[j], data, (i = 64-j)); + SHA1_Transform(context->state, context->buffer); + for ( ; i + 63 < len; i += 64) { + SHA1_Transform(context->state, &data[i]); + } + j = 0; + } + else + i = 0; + + memcpy(&context->buffer[j], &data[i], len - i); +} + +/* Add padding and return the message digest. */ +void +SHA1_Final(unsigned char digest[20], SHA1_CTX *context) +{ + unsigned long i, j; + unsigned char finalcount[8]; + + for (i = 0; i < 8; i++) { + finalcount[i] = (unsigned char)((context->count[(i >= 4 ? 0 : 1)] + >> ((3-(i & 3)) * 8) ) & 255); /* Endian independent */ + } + SHA1_Update(context, (unsigned char *) "\200", 1); + while ((context->count[0] & 504) != 448) { + SHA1_Update(context, (unsigned char *) "\0", 1); + } + SHA1_Update(context, finalcount, 8); /* Should cause a SHA1Transform() */ + for (i = 0; i < 20; i++) { + digest[i] = (unsigned char) + ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255); + } + /* Wipe variables */ + i = j = 0; + memset(context->buffer, 0, 64); + memset(context->state, 0, 20); + memset(context->count, 0, 8); + memset(&finalcount, 0, 8); +#ifdef SHA1HANDSOFF /* make SHA1Transform overwrite it's own static vars */ + SHA1Transform(context->state, context->buffer); +#endif +} + +/* + * arcfour.c + * by Frank Cusack + * 100% public domain + * + * Implemented from the description in _Applied Cryptography_, 2nd ed. + * + * ** Distribution ** of this software is unlimited and unrestricted. + * + * ** Use ** of this software is almost certainly legal; however, refer + * to . + */ + +#define swap(a, b) \ +{ \ + unsigned char t = b; \ + b = a; \ + a = t; \ +} + +/* + * Initialize arcfour from a key. + */ +void +arcfour_setkey(arcfour_context *context, const unsigned char *key, + unsigned keylen) +{ + unsigned i, j; + unsigned char K[256]; + + context->i = context->j = 0; + + for (i = 0; i < 256; i++) { + context->S[i] = i; + K[i] = key[i % keylen]; + } + + j = 0; + for (i = 0; i < 256; i++) { + j = (j + context->S[i] + K[i]) % 256; + swap(context->S[i], context->S[j]); + } + + memset(K, 0, sizeof(K)); +} + +/* + * plaintext -> ciphertext (or vice versa) + */ +void +arcfour_encrypt(arcfour_context *context, const unsigned char *in, unsigned len, + unsigned char *out) +{ + unsigned i = context->i; + unsigned j = context->j; + unsigned char *S = context->S; + unsigned char K; + + while (len--) { + i = (i + 1) % 256; + j = (j + S[i]) % 256; + swap(S[i], S[j]); + K = S[(S[i] + S[j]) % 256]; + *out++ = *in++ ^ K; + } + + context->i = i; + context->j = j; +} --- /dev/null 2004-04-06 13:56:48.000000000 -0400 +++ linux-2.4.20/drivers/net/ppp_mppe_crypto.h 2005-01-07 02:57:48.415153952 -0500 @@ -0,0 +1,40 @@ +/* + * ppp_mppe_crypto.h - cryptografic funtion prototypes for MPPE + * + * This code is Public Domain. Please see comments below. + * + * I have just put SHA1 and ARCFOUR declarations into one file + * in order to not pollute kernel namespace. + * + * Jan Dubiec , 2003-07-08 + */ + +#ifndef _PPP_MPPE_CRYPTO_ +#define _PPP_MPPE_CRYPTO_ + +/* SHA1 definitions and prototypes */ +typedef struct { + unsigned long state[5]; + unsigned long count[2]; + unsigned char buffer[64]; +} SHA1_CTX; + +#define SHA1_SIGNATURE_SIZE 20 + +extern void SHA1_Init(SHA1_CTX *); +extern void SHA1_Update(SHA1_CTX *, const unsigned char *, unsigned int); +extern void SHA1_Final(unsigned char[SHA1_SIGNATURE_SIZE], SHA1_CTX *); + +/* ARCFOUR (aka RC4) definitions and prototypes */ +typedef struct { + unsigned i; + unsigned j; + unsigned char S[256]; +} arcfour_context; + +extern void arcfour_setkey(arcfour_context *, const unsigned char *, unsigned); +extern void arcfour_encrypt(arcfour_context *, const unsigned char *, unsigned, + unsigned char *); +#define arcfour_decrypt arcfour_encrypt + +#endif /* _PPP_MPPE_CRYPTO_ */ --- /dev/null 2004-04-06 13:56:48.000000000 -0400 +++ linux-2.4.20/drivers/net/ppp_mppe_mppc_comp.c 2005-01-07 02:57:48.417153648 -0500 @@ -0,0 +1,1144 @@ +/* + * ppp_mppe_mppc_comp.c - MPPC/MPPE "compressor/decompressor" module. + * + * Copyright (c) 1994 Árpád Magosányi + * Copyright (c) 1999 Tim Hockin, Cobalt Networks Inc. + * Copyright (c) 2002, 2003 Jan Dubiec + * + * 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. + * + * Compile command: + * gcc -O2 -Wall -I/usr/src/linux/include -D__KERNEL__ -DMODULE -c ppp_mppe_mppc_comp.c + * + * ==FILEVERSION 20030807== + * + */ + +#include +#include +#include +#include + +#include +#include + +#include "ppp_mppe_crypto.h" + +/* + * State for a mppc/mppe "(de)compressor". + */ +struct ppp_mppe_state { + arcfour_context arcfour_context; + 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_OVHD 2 /* MPPE overhead */ +#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) + +/* + * Key Derivation, from RFC 3078, RFC 3079. + * Equivalent to Get_Key() for MS-CHAP as described in RFC 3079. + */ +static void +GetNewKeyFromSHA(unsigned char *MasterKey, unsigned char *SessionKey, + unsigned long SessionKeyLength, unsigned char *InterimKey) +{ + /*Pads used in key derivation */ + static unsigned char SHAPad1[40] = + { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, + 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }; + + static unsigned char SHAPad2[40] = + { 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, + 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, + 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, + 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2, 0xF2 }; + + SHA1_CTX Context; + unsigned char Digest[SHA1_SIGNATURE_SIZE]; + + SHA1_Init(&Context); + SHA1_Update(&Context, MasterKey, SessionKeyLength); + SHA1_Update(&Context, SHAPad1, sizeof(SHAPad1)); + SHA1_Update(&Context, SessionKey, SessionKeyLength); + SHA1_Update(&Context, SHAPad2, sizeof(SHAPad2)); + SHA1_Final(Digest,&Context); + memcpy(InterimKey, Digest, SessionKeyLength); +} + +static void +mppe_change_key(struct ppp_mppe_state *state, int initialize) +{ + unsigned char InterimKey[MPPE_MAX_KEY_LEN]; + + GetNewKeyFromSHA(state->master_key, state->session_key, + state->keylen, InterimKey); + if (initialize) { + memcpy(state->session_key, InterimKey, state->keylen); + } else { + arcfour_setkey(&state->arcfour_context, InterimKey, state->keylen); + arcfour_encrypt(&state->arcfour_context, InterimKey, 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; + } + } + arcfour_setkey(&state->arcfour_context, 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); + state->nextflushed = 1; + } + } + } +} + +/* 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; + 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; + } + } + } + + MOD_INC_USE_COUNT; + + if (state->mppe) { /* specific for MPPE */ + 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() */ + } + + 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->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) + arcfour_setkey(&state->arcfour_context, 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 max. 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 max. 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 max. 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 just 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 = ((40542*((((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 > 8191 || off < 1 || *p++ != *s++ || *p++ != *s++ || *p++ != *s++) + goto literal; + 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)); + } + } else { + while((*p++ == *s++) && (s < r)); + } + 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; + } + continue; + + literal: + /* 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); + } + } + + /* 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; + 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; /* Leave two octets for MPPE/MPPC bits */ + + mppe_increase_ccount(state); + + if (state->nextflushed) { + if (!state->stateless) { + state->nextflushed = 0; + } + state->bits |= MPPE_BIT_FLUSHED; + 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+2, wptr, isize-2, + osize-PPP_HDRLEN-MPPE_OVHD); + if ((complen > isize) || (complen == 0)) { + /* packet expands */ + state->nextflushed = 1; + memcpy(wptr, ibuf+2, isize-2); + olen = isize + (PPP_HDRLEN / 2) + MPPE_OVHD; + (state->stats).inc_bytes += olen; + (state->stats).inc_packets++; + } else { + state->bits |= MPPE_BIT_COMP; + olen = complen + PPP_HDRLEN + MPPE_OVHD; + (state->stats).comp_bytes += olen; + (state->stats).comp_packets++; + } + } else { + if (!state->mppc && state->mppe) { /* Do only encryption */ + /* read from ibuf, write to wptr, adjust for PPP_HDRLEN */ + arcfour_encrypt(&state->arcfour_context, ibuf+2, isize-2, wptr); + state->bits |= MPPE_BIT_ENCRYPTED; + olen = isize + (PPP_HDRLEN / 2) + MPPE_OVHD; + (state->stats).inc_bytes += olen; + (state->stats).inc_packets++; + } else { /* Do compression and then encryption - RFC3078 */ + complen = mppc_compress(state, ibuf+2, wptr, isize-2, + osize-PPP_HDRLEN-MPPE_OVHD); + if ((complen > isize) || (complen == 0)) { + /* packet expands */ + memcpy(wptr, ibuf+2, isize-2); + state->nextflushed = 1; + arcfour_encrypt(&state->arcfour_context, ibuf+2, isize-2, wptr); + olen = isize + (PPP_HDRLEN / 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. */ + arcfour_encrypt(&state->arcfour_context, wptr, complen, wptr); + olen = complen + PPP_HDRLEN + MPPE_OVHD; + (state->stats).comp_bytes += olen; + (state->stats).comp_packets++; + } + state->bits |= MPPE_BIT_ENCRYPTED; + } + } + + /* 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 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 used to use memmove() + * here, because I thought that it acts as libc's version. But + * 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; + } + } + + if (olen <= 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, olen+(PPP_HDRLEN/2)); + return DECOMP_ERROR; + } + + return (int) olen; +} + +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)) { + arcfour_setkey(&state->arcfour_context, 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. */ + arcfour_decrypt(&state->arcfour_context, ibuf+PPP_HDRLEN+MPPE_OVHD, + isize-PPP_HDRLEN-MPPE_OVHD, ibuf+PPP_HDRLEN+MPPE_OVHD); + uncomplen = mppc_decompress(state, ibuf+PPP_HDRLEN+MPPE_OVHD, + obuf, isize-PPP_HDRLEN-MPPE_OVHD, + 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 { + arcfour_decrypt(&state->arcfour_context, ibuf+PPP_HDRLEN+MPPE_OVHD, + isize-PPP_HDRLEN-MPPE_OVHD, obuf); + uncomplen = isize - (PPP_HDRLEN / 2) - MPPE_OVHD; + (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, + obuf, isize-PPP_HDRLEN-MPPE_OVHD, + 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, + isize-PPP_HDRLEN-MPPE_OVHD); + uncomplen = isize - (PPP_HDRLEN / 2) - 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 - no MPPC nor MPPE negotiated\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. + */ +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 */ +}; + +/* + 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. +*/ + +/************************************************************ + * Module support routines + ************************************************************/ + +int __init mppe_module_init(void) +{ + int 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) +{ + if (MOD_IN_USE) { + printk (KERN_INFO "MPPE/MPPC module busy, removing delayed\n"); + } else { + 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 "); +MODULE_DESCRIPTION("MPPE/MPPC encryption/compression module for Linux"); +MODULE_LICENSE("Dual BSD/GPL"); --- linux-2.4.20/include/linux/ppp-comp.h~150-mppe-mppc-0.98 1999-08-06 13:44:11.000000000 -0400 +++ linux-2.4.20/include/linux/ppp-comp.h 2005-01-07 02:58:08.293132040 -0500 @@ -24,7 +24,7 @@ * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, * OR MODIFICATIONS. * - * $Id: ppp-comp.h,v 1.6 1997/11/27 06:04:44 paulus Exp $ + * $Id: ppp-comp.h,v 1.10 2002/12/06 09:49:15 paulus Exp $ */ /* @@ -78,7 +78,7 @@ /* 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 @@ /* 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 +187,127 @@ #define DEFLATE_CHK_SEQUENCE 0 /* + * Definitions for MPPE. + */ + +#define CI_MPPE 18 /* config option for MPPE */ +#define CILEN_MPPE 6 /* length of config option */ + +#define MPPE_PAD 4 /* MPPE growth per frame */ +#define MPPE_MAX_KEY_LEN 16 /* largest key length (128-bit) */ + +/* option bits for ccp_options.mppe */ +#define MPPE_OPT_40 0x01 /* 40 bit */ +#define MPPE_OPT_128 0x02 /* 128 bit */ +#define MPPE_OPT_STATEFUL 0x04 /* stateful mode */ +/* unsupported opts */ +#define MPPE_OPT_56 0x08 /* 56 bit */ +#define MPPE_OPT_MPPC 0x10 /* MPPC compression */ +#define MPPE_OPT_D 0x20 /* Unknown */ +#define MPPE_OPT_UNSUPPORTED (MPPE_OPT_56|MPPE_OPT_MPPC|MPPE_OPT_D) +#define MPPE_OPT_UNKNOWN 0x40 /* Bits !defined in RFC 3078 were set */ + +/* + * This is not nice ... the alternative is a bitfield struct though. + * And unfortunately, we cannot share the same bits for the option + * names above since C and H are the same bit. We could do a u_int32 + * but then we have to do a htonl() all the time and/or we still need + * to know which octet is which. + */ +#define MPPE_C_BIT 0x01 /* MPPC */ +#define MPPE_D_BIT 0x10 /* Obsolete, usage unknown */ +#define MPPE_L_BIT 0x20 /* 40-bit */ +#define MPPE_S_BIT 0x40 /* 128-bit */ +#define MPPE_M_BIT 0x80 /* 56-bit, not supported */ +#define MPPE_H_BIT 0x01 /* Stateless (in a different byte) */ + +/* Does not include H bit; used for least significant octet only. */ +#define MPPE_ALL_BITS (MPPE_D_BIT|MPPE_L_BIT|MPPE_S_BIT|MPPE_M_BIT|MPPE_H_BIT) + +/* Build a CI from mppe opts (see RFC 3078) */ +#define MPPE_OPTS_TO_CI(opts, ci) \ + do { \ + u_char *ptr = ci; /* u_char[4] */ \ + \ + /* H bit */ \ + if (opts & MPPE_OPT_STATEFUL) \ + *ptr++ = 0x0; \ + else \ + *ptr++ = MPPE_H_BIT; \ + *ptr++ = 0; \ + *ptr++ = 0; \ + \ + /* S,L bits */ \ + *ptr = 0; \ + if (opts & MPPE_OPT_128) \ + *ptr |= MPPE_S_BIT; \ + if (opts & MPPE_OPT_40) \ + *ptr |= MPPE_L_BIT; \ + /* M,D,C bits not supported */ \ + } while (/* CONSTCOND */ 0) + +/* The reverse of the above */ +#define MPPE_CI_TO_OPTS(ci, opts) \ + do { \ + u_char *ptr = ci; /* u_char[4] */ \ + \ + opts = 0; \ + \ + /* H bit */ \ + if (!(ptr[0] & MPPE_H_BIT)) \ + opts |= MPPE_OPT_STATEFUL; \ + \ + /* S,L bits */ \ + if (ptr[3] & MPPE_S_BIT) \ + opts |= MPPE_OPT_128; \ + if (ptr[3] & MPPE_L_BIT) \ + opts |= MPPE_OPT_40; \ + \ + /* M,D,C bits */ \ + if (ptr[3] & MPPE_M_BIT) \ + opts |= MPPE_OPT_56; \ + if (ptr[3] & MPPE_D_BIT) \ + opts |= MPPE_OPT_D; \ + if (ptr[3] & MPPE_C_BIT) \ + opts |= MPPE_OPT_MPPC; \ + \ + /* Other bits */ \ + if (ptr[0] & ~MPPE_H_BIT) \ + opts |= MPPE_OPT_UNKNOWN; \ + if (ptr[1] || ptr[2]) \ + opts |= MPPE_OPT_UNKNOWN; \ + if (ptr[3] & ~MPPE_ALL_BITS) \ + opts |= MPPE_OPT_UNKNOWN; \ + } while (/* CONSTCOND */ 0) + +/* MPPE/MPPC definitions by J.D.*/ +#define MPPE_STATELESS MPPE_H_BIT /* configuration bit H */ +#define MPPE_40BIT MPPE_L_BIT /* configuration bit L */ +#define MPPE_56BIT MPPE_M_BIT /* configuration bit M */ +#define MPPE_128BIT MPPE_S_BIT /* configuration bit S */ +#define MPPE_MPPC MPPE_C_BIT /* 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. */