rename packages/ to recipes/ per earlier agreement

See links below for more details:
http://thread.gmane.org/gmane.comp.handhelds.openembedded/21326
http://thread.gmane.org/gmane.comp.handhelds.openembedded/21816

Signed-off-by: Denys Dmytriyenko <denis@denix.org>
Acked-by: Mike Westerhof <mwester@dls.net>
Acked-by: Philip Balister <philip@balister.org>
Acked-by: Khem Raj <raj.khem@gmail.com>
Acked-by: Marcin Juszkiewicz <hrw@openembedded.org>
Acked-by: Koen Kooi <koen@openembedded.org>
Acked-by: Frans Meulenbroeks <fransmeulenbroeks@gmail.com>

1 files changed, 1665 insertions, 0 deletions

diff --git a/recipes/linux/linux-mtx-2-2.4.27/39-mppe-mpc.patch b/recipes/linux/linux-mtx-2-2.4.27/39-mppe-mpc.patch
new file mode 100644
index 0000000000..28ce19d467
--- /dev/null
+++ b/recipes/linux/linux-mtx-2-2.4.27/39-mppe-mpc.patch
@@ -0,0 +1,1665 @@
+diff -ruN linux.orig/Documentation/Configure.help linux/Documentation/Configure.help
+--- linux.orig/Documentation/Configure.help	2004-08-08 12:14:49.000000000 +0200
++++ linux/Documentation/Configure.help	2004-08-15 09:22:18.000000000 +0200
+@@ -9905,6 +9905,28 @@
+   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.
+diff -ruN linux.orig/crypto/Config.in linux/crypto/Config.in
+--- linux.orig/crypto/Config.in	2004-08-08 12:14:50.000000000 +0200
++++ linux/crypto/Config.in	2004-08-15 11:36:18.000000000 +0200
+@@ -11,7 +11,9 @@
+      "$CONFIG_INET6_AH" = "y" -o \
+      "$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 \
++     "$CONFIG_PPP_MPPE_MPPC" = "m" ]; then
+   define_bool CONFIG_CRYPTO y
+ else
+   bool 'Cryptographic API' CONFIG_CRYPTO
+@@ -44,6 +46,7 @@
+   else
+     tristate       '  MD5 digest algorithm' CONFIG_CRYPTO_MD5
+   fi
++
+   if [ "$CONFIG_INET_AH" = "y" -o \
+        "$CONFIG_INET_AH" = "m" -o \
+        "$CONFIG_INET_ESP" = "y" -o \
+@@ -51,11 +54,24 @@
+        "$CONFIG_INET6_AH" = "y" -o \
+        "$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
+   if [ "$CONFIG_INET_ESP" = "y" -o \
+@@ -73,7 +89,20 @@
+   tristate       '  CAST5 (CAST-128) cipher algorithm' CONFIG_CRYPTO_CAST5
+   tristate       '  CAST6 (CAST-256) cipher algorithm' CONFIG_CRYPTO_CAST6
+   tristate       '  TEA and XTEA cipher algorithms' CONFIG_CRYPTO_TEA
++
++  if [ "$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 \
+diff -ruN linux.orig/drivers/net/Config.in linux/drivers/net/Config.in
+--- linux.orig/drivers/net/Config.in	2004-08-08 12:14:52.000000000 +0200
++++ linux/drivers/net/Config.in	2004-08-08 12:17:43.000000000 +0200
+@@ -325,6 +325,7 @@
+    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_MPPC $CONFIG_PPP
+    if [ "$CONFIG_EXPERIMENTAL" = "y" ]; then
+       dep_tristate '  PPP over Ethernet (EXPERIMENTAL)' CONFIG_PPPOE $CONFIG_PPP
+    fi
+diff -ruN linux.orig/drivers/net/Makefile linux/drivers/net/Makefile
+--- linux.orig/drivers/net/Makefile	2004-08-08 12:14:52.000000000 +0200
++++ linux/drivers/net/Makefile	2004-08-08 12:17:43.000000000 +0200
+@@ -161,6 +161,7 @@
+ obj-$(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
+diff -ruN linux.orig/drivers/net/ppp_generic.c linux/drivers/net/ppp_generic.c
+--- linux.orig/drivers/net/ppp_generic.c	2003-08-25 13:44:42.000000000 +0200
++++ linux/drivers/net/ppp_generic.c	2004-08-08 12:17:43.000000000 +0200
+@@ -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 @@
+ 	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 @@
+ 	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 @@
+ 	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 @@
+ 			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 @@
+ 	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 @@
+ 	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 @@
+ 	/* 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)
+diff -ruN linux.orig/drivers/net/ppp_mppe_mppc.c linux/drivers/net/ppp_mppe_mppc.c
+--- linux.orig/drivers/net/ppp_mppe_mppc.c	1970-01-01 01:00:00.000000000 +0100
++++ linux/drivers/net/ppp_mppe_mppc.c	2004-08-15 10:12:23.000000000 +0200
+@@ -0,0 +1,1269 @@
++/*
++ * 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) 2002-2004 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 20040815==
++ *
++ */
++
++#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		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)
++
++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
++GetNewKeyFromSHA(struct ppp_mppe_state *state, unsigned char *MasterKey,
++		 unsigned char *SessionKey, unsigned long SessionKeyLength,
++		 unsigned char *InterimKey)
++{
++    /*Pads used in key derivation */
++    static const 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 const 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
++    };
++
++    unsigned char Digest[20]; /* SHA1_DIGEST_SIZE = 20 */
++    struct scatterlist sg[2];
++
++    crypto_digest_init(state->sha1_tfm);
++
++    setup_sg(sg, MasterKey, SessionKeyLength);
++    crypto_digest_update(state->sha1_tfm, sg, 1);
++
++    setup_sg(sg, SHAPad1, sizeof(SHAPad1));
++    crypto_digest_update(state->sha1_tfm, sg, 1);
++
++    setup_sg(sg, SessionKey, SessionKeyLength);
++    crypto_digest_update(state->sha1_tfm, sg, 1);
++
++    setup_sg(sg, SHAPad2, sizeof(SHAPad2));
++    crypto_digest_update(state->sha1_tfm, sg, 1);
++
++    crypto_digest_final(state->sha1_tfm, Digest);
++
++    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, state->master_key, state->session_key,
++		     state->keylen, InterimKey);
++    if (initialize) {
++	memcpy(state->session_key, InterimKey, state->keylen);
++    } else {
++	arc4_setkey(state, InterimKey, state->keylen);
++	arc4_encrypt(state, 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;
++	}
++    }
++    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;
++    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 SHA1 algorithm */
++	state->sha1_tfm = crypto_alloc_tfm("sha1", 0);
++	if (state->sha1_tfm == NULL) {
++	    vfree(state->hash);
++	    vfree(state->hist);
++	    kfree(state);
++	    printk(KERN_ERR "%s: cannot load SHA1 module\n", fname);
++	    return NULL;
++	}
++
++	/* Load ARC4 algorithm */
++	state->arc4_tfm = crypto_alloc_tfm("arc4", 0);
++	if (state->arc4_tfm == NULL) {
++	    crypto_free_tfm(state->sha1_tfm);
++	    vfree(state->hash);
++	    vfree(state->hist);
++	    kfree(state);
++	    printk(KERN_ERR "%s: cannot load ARC4 module\n", fname);
++	    return NULL;
++	}
++
++	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 = 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)
++{
++    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");
+diff -ruN linux.orig/include/linux/ppp-comp.h linux/include/linux/ppp-comp.h
+--- linux.orig/include/linux/ppp-comp.h	1999-08-06 19:44:11.000000000 +0200
++++ linux/include/linux/ppp-comp.h	2004-08-08 12:17:43.000000000 +0200
+@@ -1,34 +1,42 @@
+ /*
+  * ppp-comp.h - Definitions for doing PPP packet compression.
+  *
+- * Copyright (c) 1994 The Australian National University.
+- * All rights reserved.
++ * Copyright (c) 1984 Paul Mackerras. All rights reserved.
+  *
+- * 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 Australian National University
+- * makes no representations about the suitability of this software for
+- * any purpose.
+- *
+- * IN NO EVENT SHALL THE AUSTRALIAN NATIONAL UNIVERSITY BE LIABLE TO ANY
+- * PARTY FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
+- * ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
+- * THE AUSTRALIAN NATIONAL UNIVERSITY HAVE BEEN ADVISED OF THE POSSIBILITY
+- * OF SUCH DAMAGE.
+- *
+- * THE AUSTRALIAN NATIONAL UNIVERSITY SPECIFICALLY DISCLAIMS ANY WARRANTIES,
+- * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+- * AND FITNESS FOR A PARTICULAR PURPOSE.  THE SOFTWARE PROVIDED HEREUNDER IS
+- * ON AN "AS IS" BASIS, AND THE AUSTRALIAN NATIONAL UNIVERSITY HAS NO
+- * OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS,
+- * OR MODIFICATIONS.
++ * Redistribution and use in source and binary forms, with or without
++ * modification, are permitted provided that the following conditions
++ * are met:
+  *
+- * $Id: ppp-comp.h,v 1.6 1997/11/27 06:04:44 paulus Exp $
++ * 1. Redistributions of source code must retain the above copyright
++ *    notice, this list of conditions and the following disclaimer.
++ *
++ * 2. Redistributions in binary form must reproduce the above copyright
++ *    notice, this list of conditions and the following disclaimer in
++ *    the documentation and/or other materials provided with the
++ *    distribution.
++ *
++ * 3. The name(s) of the authors of this software must not be used to
++ *    endorse or promote products derived from this software without
++ *    prior written permission.
++ *
++ * 4. Redistributions of any form whatsoever must retain the following
++ *    acknowledgment:
++ *    "This product includes software developed by Paul Mackerras
++ *     <paulus@samba.org>".
++ *
++ * THE AUTHORS OF THIS SOFTWARE DISCLAIM ALL WARRANTIES WITH REGARD TO
++ * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
++ * AND FITNESS, IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
++ * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
++ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
++ * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
++ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
++ *
++ * $Id: ppp-comp.h,v 1.10 2002/12/06 09:49:15 paulus Exp $
+  */
+ 
+ /*
+- *  ==FILEVERSION 980319==
++ *  ==FILEVERSION 20040509==
+  *
+  *  NOTE TO MAINTAINERS:
+  *     If you modify this file at all, please set the above date.
+@@ -78,7 +86,7 @@
+ 
+ 	/* 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 +107,7 @@
+ 
+ 	/* 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 +195,42 @@
+ #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.
+  */
+