mirror of
git://projects.qi-hardware.com/openwrt-xburst.git
synced 2024-09-12 19:19:18 +03:00
git-svn-id: svn://svn.openwrt.org/openwrt/trunk/openwrt@2877 3c298f89-4303-0410-b956-a3cf2f4a3e73
1650 lines
53 KiB
Diff
1650 lines
53 KiB
Diff
MPPE/MPPC kernel module for Linux
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|
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Microsoft Point-to-Point Encryption / Compression support
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http://www.polbox.com/h/hs001/linux-2.4.29-mppe-mppc-1.3.patch.gz
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diff -ruN linux-2.4.29.orig/Documentation/Configure.help linux-2.4.29/Documentation/Configure.help
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--- linux-2.4.29.orig/Documentation/Configure.help 2005-02-02 22:18:18.000000000 +0100
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+++ linux-2.4.29/Documentation/Configure.help 2005-02-02 22:26:37.000000000 +0100
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@@ -9969,6 +9969,28 @@
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module; it is called bsd_comp.o and will show up in the directory
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modules once you have said "make modules". If unsure, say N.
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+Microsoft PPP compression/encryption (MPPC/MPPE)
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+CONFIG_PPP_MPPE_MPPC
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+ Support for the Microsoft Point-To-Point Compression (RFC2118) and
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+ Microsoft Point-To-Point Encryption (RFC3078). These protocols are
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+ supported by Microsoft Windows and wide range of "hardware" access
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+ servers. MPPE is common protocol in Virtual Private Networks. According
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+ to RFC3078, MPPE supports 40, 56 and 128-bit key lengths. Depending on
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+ PPP daemon configuration on both ends of the link, following scenarios
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+ are possible:
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+ - only compression (MPPC) is used,
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+ - only encryption (MPPE) is used,
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+ - compression and encryption (MPPC+MPPE) are used.
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+
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+ Please note that Hi/Fn (http://www.hifn.com) holds patent on MPPC so
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+ you should check if this patent is valid in your country in order to
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+ avoid legal problems.
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+
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+ For more information please visit http://free.polbox.pl/h/hs001
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+
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+ To compile this driver as a module, choose M here. The module will
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+ be called ppp_mppe_mppc.o.
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+
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PPP over Ethernet
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CONFIG_PPPOE
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Support for PPP over Ethernet.
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diff -ruN linux-2.4.29.orig/crypto/Config.in linux-2.4.29/crypto/Config.in
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--- linux-2.4.29.orig/crypto/Config.in 2005-02-02 22:18:14.000000000 +0100
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+++ linux-2.4.29/crypto/Config.in 2005-02-02 22:26:37.000000000 +0100
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@@ -11,7 +11,9 @@
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"$CONFIG_INET6_AH" = "y" -o \
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"$CONFIG_INET6_AH" = "m" -o \
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"$CONFIG_INET6_ESP" = "y" -o \
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- "$CONFIG_INET6_ESP" = "m" ]; then
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+ "$CONFIG_INET6_ESP" = "m" -o \
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+ "$CONFIG_PPP_MPPE_MPPC" = "y" -o \
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+ "$CONFIG_PPP_MPPE_MPPC" = "m" ]; then
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define_bool CONFIG_CRYPTO y
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else
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bool 'Cryptographic API' CONFIG_CRYPTO
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@@ -51,11 +53,24 @@
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"$CONFIG_INET6_AH" = "y" -o \
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"$CONFIG_INET6_AH" = "m" -o \
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"$CONFIG_INET6_ESP" = "y" -o \
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- "$CONFIG_INET6_ESP" = "m" ]; then
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- define_bool CONFIG_CRYPTO_SHA1 y
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- else
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- tristate ' SHA1 digest algorithm' CONFIG_CRYPTO_SHA1
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+ "$CONFIG_INET6_ESP" = "m" -o \
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+ "$CONFIG_PPP_MPPE_MPPC" = "y" -o \
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+ "$CONFIG_PPP_MPPE_MPPC" = "m" ]; then
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+ if [ "$CONFIG_INET_AH" = "y" -o \
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+ "$CONFIG_INET_ESP" = "y" -o \
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+ "$CONFIG_INET6_AH" = "y" -o \
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+ "$CONFIG_INET6_ESP" = "y" -o \
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+ "$CONFIG_PPP_MPPE_MPPC" = "y" ]; then
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+ define_tristate CONFIG_CRYPTO_SHA1 y
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+ else
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+ if [ "$CONFIG_CRYPTO_SHA1" != "y" -a \
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+ "$CONFIG_CRYPTO_SHA1" != "m" ]; then
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+ define_tristate CONFIG_CRYPTO_SHA1 m
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+ fi
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+ fi
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fi
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+ tristate ' SHA1 digest algorithm' CONFIG_CRYPTO_SHA1
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+
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tristate ' SHA256 digest algorithm' CONFIG_CRYPTO_SHA256
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tristate ' SHA384 and SHA512 digest algorithms' CONFIG_CRYPTO_SHA512
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tristate ' Whirlpool digest algorithms' CONFIG_CRYPTO_WP512
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@@ -76,7 +91,20 @@
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tristate ' TEA and XTEA cipher algorithms' CONFIG_CRYPTO_TEA
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tristate ' Khazad cipher algorithm' CONFIG_CRYPTO_KHAZAD
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tristate ' Anubis cipher algorithm' CONFIG_CRYPTO_ANUBIS
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+
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+ if [ "$CONFIG_PPP_MPPE_MPPC" = "y" -o \
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+ "$CONFIG_PPP_MPPE_MPPC" = "m" ]; then
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+ if [ "$CONFIG_PPP_MPPE_MPPC" = "y" ]; then
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+ define_tristate CONFIG_CRYPTO_ARC4 y
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+ else
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+ if [ "$CONFIG_CRYPTO_ARC4" != "y" -a \
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+ "$CONFIG_CRYPTO_ARC4" != "m" ]; then
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+ define_tristate CONFIG_CRYPTO_ARC4 m
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+ fi
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+ fi
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+ fi
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tristate ' ARC4 cipher algorithm' CONFIG_CRYPTO_ARC4
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+
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if [ "$CONFIG_INET_IPCOMP" = "y" -o \
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"$CONFIG_INET_IPCOMP" = "m" -o \
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"$CONFIG_INET6_IPCOMP" = "y" -o \
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diff -ruN linux-2.4.29.orig/drivers/net/Config.in linux-2.4.29/drivers/net/Config.in
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--- linux-2.4.29.orig/drivers/net/Config.in 2005-02-02 22:17:31.000000000 +0100
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+++ linux-2.4.29/drivers/net/Config.in 2005-02-02 22:26:37.000000000 +0100
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@@ -332,6 +332,7 @@
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dep_tristate ' PPP support for sync tty ports' CONFIG_PPP_SYNC_TTY $CONFIG_PPP
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dep_tristate ' PPP Deflate compression' CONFIG_PPP_DEFLATE $CONFIG_PPP
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dep_tristate ' PPP BSD-Compress compression' CONFIG_PPP_BSDCOMP $CONFIG_PPP
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+ dep_tristate ' Microsoft PPP compression/encryption (MPPC/MPPE)' CONFIG_PPP_MPPE_MPPC $CONFIG_PPP
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if [ "$CONFIG_EXPERIMENTAL" = "y" ]; then
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dep_tristate ' PPP over Ethernet (EXPERIMENTAL)' CONFIG_PPPOE $CONFIG_PPP
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fi
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diff -ruN linux-2.4.29.orig/drivers/net/Makefile linux-2.4.29/drivers/net/Makefile
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--- linux-2.4.29.orig/drivers/net/Makefile 2005-02-02 22:17:23.000000000 +0100
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+++ linux-2.4.29/drivers/net/Makefile 2005-02-02 22:26:37.000000000 +0100
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@@ -163,6 +163,7 @@
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obj-$(CONFIG_PPP_SYNC_TTY) += ppp_synctty.o
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obj-$(CONFIG_PPP_DEFLATE) += ppp_deflate.o
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obj-$(CONFIG_PPP_BSDCOMP) += bsd_comp.o
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+obj-$(CONFIG_PPP_MPPE_MPPC) += ppp_mppe_mppc.o
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obj-$(CONFIG_PPPOE) += pppox.o pppoe.o
|
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obj-$(CONFIG_SLIP) += slip.o
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diff -ruN linux-2.4.29.orig/drivers/net/ppp_generic.c linux-2.4.29/drivers/net/ppp_generic.c
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--- linux-2.4.29.orig/drivers/net/ppp_generic.c 2005-02-02 22:17:24.000000000 +0100
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+++ linux-2.4.29/drivers/net/ppp_generic.c 2005-02-02 22:26:37.000000000 +0100
|
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@@ -19,7 +19,7 @@
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* PPP driver, written by Michael Callahan and Al Longyear, and
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* subsequently hacked by Paul Mackerras.
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*
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- * ==FILEVERSION 20020217==
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+ * ==FILEVERSION 20040509==
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*/
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#include <linux/config.h>
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@@ -102,6 +102,7 @@
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spinlock_t rlock; /* lock for receive side 58 */
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spinlock_t wlock; /* lock for transmit side 5c */
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int mru; /* max receive unit 60 */
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+ int mru_alloc; /* MAX(1500,MRU) for dev_alloc_skb() */
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unsigned int flags; /* control bits 64 */
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unsigned int xstate; /* transmit state bits 68 */
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unsigned int rstate; /* receive state bits 6c */
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@@ -552,7 +553,9 @@
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case PPPIOCSMRU:
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if (get_user(val, (int *) arg))
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break;
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- ppp->mru = val;
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+ ppp->mru_alloc = ppp->mru = val;
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+ if (ppp->mru_alloc < PPP_MRU)
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+ ppp->mru_alloc = PPP_MRU; /* increase for broken peers */
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err = 0;
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break;
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@@ -1025,14 +1028,37 @@
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case PPP_CCP:
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/* peek at outbound CCP frames */
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ppp_ccp_peek(ppp, skb, 0);
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+ /*
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+ * When LZS or MPPE/MPPC has been negotiated we don't send
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+ * CCP_RESETACK after receiving CCP_RESETREQ; in fact pppd
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+ * sends such a packet but we silently discard it here
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+ */
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+ if (CCP_CODE(skb->data+2) == CCP_RESETACK
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+ && (ppp->xcomp->compress_proto == CI_MPPE
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+ || ppp->xcomp->compress_proto == CI_LZS)) {
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+ --ppp->stats.tx_packets;
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+ ppp->stats.tx_bytes -= skb->len - 2;
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+ kfree_skb(skb);
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+ return;
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+ }
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break;
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}
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/* try to do packet compression */
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if ((ppp->xstate & SC_COMP_RUN) && ppp->xc_state != 0
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&& proto != PPP_LCP && proto != PPP_CCP) {
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- new_skb = alloc_skb(ppp->dev->mtu + ppp->dev->hard_header_len,
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- GFP_ATOMIC);
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+ int comp_ovhd = 0;
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+ /*
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+ * because of possible data expansion when MPPC or LZS
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+ * is used, allocate compressor's buffer 12.5% bigger
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+ * than MTU
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+ */
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+ if (ppp->xcomp->compress_proto == CI_MPPE)
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+ comp_ovhd = ((ppp->dev->mtu * 9) / 8) + 1 + MPPE_OVHD;
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+ else if (ppp->xcomp->compress_proto == CI_LZS)
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+ comp_ovhd = ((ppp->dev->mtu * 9) / 8) + 1 + LZS_OVHD;
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+ new_skb = alloc_skb(ppp->dev->mtu + ppp->dev->hard_header_len
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+ + comp_ovhd, GFP_ATOMIC);
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if (new_skb == 0) {
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printk(KERN_ERR "PPP: no memory (comp pkt)\n");
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goto drop;
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@@ -1050,9 +1076,21 @@
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skb = new_skb;
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skb_put(skb, len);
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skb_pull(skb, 2); /* pull off A/C bytes */
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- } else {
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+ } else if (len == 0) {
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/* didn't compress, or CCP not up yet */
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kfree_skb(new_skb);
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+ } else {
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+ /*
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+ * (len < 0)
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+ * MPPE requires that we do not send unencrypted
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+ * frames. The compressor will return -1 if we
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+ * should drop the frame. We cannot simply test
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+ * the compress_proto because MPPE and MPPC share
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+ * the same number.
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+ */
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+ printk(KERN_ERR "ppp: compressor dropped pkt\n");
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+ kfree_skb(new_skb);
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+ goto drop;
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}
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}
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@@ -1540,14 +1578,15 @@
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int len;
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if (proto == PPP_COMP) {
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- ns = dev_alloc_skb(ppp->mru + PPP_HDRLEN);
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+ ns = dev_alloc_skb(ppp->mru_alloc + PPP_HDRLEN);
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if (ns == 0) {
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printk(KERN_ERR "ppp_decompress_frame: no memory\n");
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goto err;
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}
|
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/* the decompressor still expects the A/C bytes in the hdr */
|
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len = ppp->rcomp->decompress(ppp->rc_state, skb->data - 2,
|
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- skb->len + 2, ns->data, ppp->mru + PPP_HDRLEN);
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+ skb->len + 2, ns->data,
|
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+ ppp->mru_alloc + PPP_HDRLEN);
|
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if (len < 0) {
|
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/* Pass the compressed frame to pppd as an
|
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error indication. */
|
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@@ -1573,7 +1612,14 @@
|
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return skb;
|
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|
||
err:
|
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- ppp->rstate |= SC_DC_ERROR;
|
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+ if (ppp->rcomp->compress_proto != CI_MPPE
|
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+ && ppp->rcomp->compress_proto != CI_LZS) {
|
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+ /*
|
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+ * If decompression protocol isn't MPPE/MPPC or LZS, we set
|
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+ * SC_DC_ERROR flag and wait for CCP_RESETACK
|
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+ */
|
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+ ppp->rstate |= SC_DC_ERROR;
|
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+ }
|
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ppp_receive_error(ppp);
|
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return skb;
|
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}
|
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@@ -2253,6 +2299,7 @@
|
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/* Initialize the new ppp unit */
|
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ppp->file.index = unit;
|
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ppp->mru = PPP_MRU;
|
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+ ppp->mru_alloc = PPP_MRU;
|
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init_ppp_file(&ppp->file, INTERFACE);
|
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ppp->file.hdrlen = PPP_HDRLEN - 2; /* don't count proto bytes */
|
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for (i = 0; i < NUM_NP; ++i)
|
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diff -ruN linux-2.4.29.orig/drivers/net/ppp_mppe_mppc.c linux-2.4.29/drivers/net/ppp_mppe_mppc.c
|
||
--- linux-2.4.29.orig/drivers/net/ppp_mppe_mppc.c 1970-01-01 01:00:00.000000000 +0100
|
||
+++ linux-2.4.29/drivers/net/ppp_mppe_mppc.c 2005-02-02 23:07:40.000000000 +0100
|
||
@@ -0,0 +1,1312 @@
|
||
+/*
|
||
+ * ppp_mppe_mppc.c - MPPC/MPPE "compressor/decompressor" module.
|
||
+ *
|
||
+ * Copyright (c) 1994 <20>rp<72>d Magos<6F>nyi <mag@bunuel.tii.matav.hu>
|
||
+ * Copyright (c) 1999 Tim Hockin, Cobalt Networks Inc. <thockin@cobaltnet.com>
|
||
+ * Copyright (c) 2002-2005 Jan Dubiec <jdx@slackware.pl>
|
||
+ *
|
||
+ * Permission to use, copy, modify, and distribute this software and its
|
||
+ * documentation is hereby granted, provided that the above copyright
|
||
+ * notice appears in all copies. This software is provided without any
|
||
+ * warranty, express or implied.
|
||
+ *
|
||
+ * The code is based on MPPE kernel module written by <20>rp<72>d Magos<6F>nyi and
|
||
+ * Tim Hockin which can be found on http://planetmirror.com/pub/mppe/.
|
||
+ * I have added MPPC and 56 bit session keys support in MPPE.
|
||
+ *
|
||
+ * WARNING! Although this is open source code, its usage in some countries
|
||
+ * (in particular in the USA) may violate Stac Inc. patent for MPPC.
|
||
+ *
|
||
+ * ==FILEVERSION 20050202==
|
||
+ *
|
||
+ */
|
||
+
|
||
+#include <linux/init.h>
|
||
+#include <linux/module.h>
|
||
+#include <linux/mm.h>
|
||
+#include <linux/slab.h>
|
||
+#include <asm/scatterlist.h>
|
||
+#include <linux/vmalloc.h>
|
||
+#include <linux/crypto.h>
|
||
+
|
||
+#include <linux/ppp_defs.h>
|
||
+#include <linux/ppp-comp.h>
|
||
+
|
||
+/*
|
||
+ * In 2.4.x kernels macro offset_in_page() is not defined in linux/mm.h so
|
||
+ * we define it here; PAGE_MASK is defined in asm/page.h which is included
|
||
+ * by linux/mm.h.
|
||
+ */
|
||
+#define offset_in_page(p) ((unsigned long)(p) & ~PAGE_MASK)
|
||
+
|
||
+/*
|
||
+ * State for a mppc/mppe "(de)compressor".
|
||
+ */
|
||
+struct ppp_mppe_state {
|
||
+ struct crypto_tfm *arc4_tfm;
|
||
+ struct crypto_tfm *sha1_tfm;
|
||
+ u8 *sha1_digest;
|
||
+ u8 master_key[MPPE_MAX_KEY_LEN];
|
||
+ u8 session_key[MPPE_MAX_KEY_LEN];
|
||
+ u8 mppc; /* do we use compression (MPPC)? */
|
||
+ u8 mppe; /* do we use encryption (MPPE)? */
|
||
+ u8 keylen; /* key length in bytes */
|
||
+ u8 bitkeylen; /* key length in bits */
|
||
+ u16 ccount; /* coherency counter */
|
||
+ u16 bits; /* MPPC/MPPE control bits */
|
||
+ u8 stateless; /* do we use stateless mode? */
|
||
+ u8 nextflushed; /* set A bit in the next outgoing packet;
|
||
+ used only by compressor*/
|
||
+ u8 flushexpected; /* drop packets until A bit is received;
|
||
+ used only by decompressor*/
|
||
+ u8 *hist; /* MPPC history */
|
||
+ u16 *hash; /* Hash table; used only by compressor */
|
||
+ u16 histptr; /* history "cursor" */
|
||
+ int unit;
|
||
+ int debug;
|
||
+ int mru;
|
||
+ struct compstat stats;
|
||
+};
|
||
+
|
||
+#define MPPE_HIST_LEN 8192 /* MPPC history size */
|
||
+#define MPPE_MAX_CCOUNT 0x0FFF /* max. coherency counter value */
|
||
+
|
||
+#define MPPE_BIT_FLUSHED 0x80 /* bit A */
|
||
+#define MPPE_BIT_RESET 0x40 /* bit B */
|
||
+#define MPPE_BIT_COMP 0x20 /* bit C */
|
||
+#define MPPE_BIT_ENCRYPTED 0x10 /* bit D */
|
||
+
|
||
+#define MPPE_SALT0 0xD1 /* values used in MPPE key derivation */
|
||
+#define MPPE_SALT1 0x26 /* according to RFC3079 */
|
||
+#define MPPE_SALT2 0x9E
|
||
+
|
||
+#define MPPE_CCOUNT(x) ((((x)[4] & 0x0f) << 8) + (x)[5])
|
||
+#define MPPE_BITS(x) ((x)[4] & 0xf0)
|
||
+#define MPPE_CTRLHI(x) ((((x)->ccount & 0xf00)>>8)|((x)->bits))
|
||
+#define MPPE_CTRLLO(x) ((x)->ccount & 0xff)
|
||
+
|
||
+/*
|
||
+ * Kernel Crypto API needs its arguments to be in kmalloc'd memory, not in the
|
||
+ * module static data area. That means sha_pad needs to be kmalloc'd. It is done
|
||
+ * in mppe_module_init(). This has been pointed out on 30th July 2004 by Oleg
|
||
+ * Makarenko on pptpclient-devel mailing list.
|
||
+ */
|
||
+#define SHA1_PAD_SIZE 40
|
||
+struct sha_pad {
|
||
+ unsigned char sha_pad1[SHA1_PAD_SIZE];
|
||
+ unsigned char sha_pad2[SHA1_PAD_SIZE];
|
||
+};
|
||
+static struct sha_pad *sha_pad;
|
||
+
|
||
+static inline void
|
||
+setup_sg(struct scatterlist *sg, const void *address, unsigned int length)
|
||
+{
|
||
+ sg[0].page = virt_to_page(address);
|
||
+ sg[0].offset = offset_in_page(address);
|
||
+ sg[0].length = length;
|
||
+}
|
||
+
|
||
+static inline void
|
||
+arc4_setkey(struct ppp_mppe_state *state, const unsigned char *key,
|
||
+ const unsigned int keylen)
|
||
+{
|
||
+ crypto_cipher_setkey(state->arc4_tfm, key, keylen);
|
||
+}
|
||
+
|
||
+static inline void
|
||
+arc4_encrypt(struct ppp_mppe_state *state, const unsigned char *in,
|
||
+ const unsigned int len, unsigned char *out)
|
||
+{
|
||
+ struct scatterlist sgin[4], sgout[4];
|
||
+
|
||
+ setup_sg(sgin, in, len);
|
||
+ setup_sg(sgout, out, len);
|
||
+ crypto_cipher_encrypt(state->arc4_tfm, sgout, sgin, len);
|
||
+}
|
||
+
|
||
+#define arc4_decrypt arc4_encrypt
|
||
+
|
||
+/*
|
||
+ * Key Derivation, from RFC 3078, RFC 3079.
|
||
+ * Equivalent to Get_Key() for MS-CHAP as described in RFC 3079.
|
||
+ */
|
||
+static void
|
||
+get_new_key_from_sha(struct ppp_mppe_state *state, unsigned char *interim_key)
|
||
+{
|
||
+ struct scatterlist sg[4];
|
||
+
|
||
+ setup_sg(&sg[0], state->master_key, state->keylen);
|
||
+ setup_sg(&sg[1], sha_pad->sha_pad1, sizeof(sha_pad->sha_pad1));
|
||
+ setup_sg(&sg[2], state->session_key, state->keylen);
|
||
+ setup_sg(&sg[3], sha_pad->sha_pad2, sizeof(sha_pad->sha_pad2));
|
||
+
|
||
+ crypto_digest_digest (state->sha1_tfm, sg, 4, state->sha1_digest);
|
||
+
|
||
+ memcpy(interim_key, state->sha1_digest, state->keylen);
|
||
+}
|
||
+
|
||
+static void
|
||
+mppe_change_key(struct ppp_mppe_state *state, int initialize)
|
||
+{
|
||
+ unsigned char interim_key[MPPE_MAX_KEY_LEN];
|
||
+
|
||
+ get_new_key_from_sha(state, interim_key);
|
||
+ if (initialize) {
|
||
+ memcpy(state->session_key, interim_key, state->keylen);
|
||
+ } else {
|
||
+ arc4_setkey(state, interim_key, state->keylen);
|
||
+ arc4_encrypt(state, interim_key, state->keylen, state->session_key);
|
||
+ }
|
||
+ if (state->keylen == 8) {
|
||
+ if (state->bitkeylen == 40) {
|
||
+ state->session_key[0] = MPPE_SALT0;
|
||
+ state->session_key[1] = MPPE_SALT1;
|
||
+ state->session_key[2] = MPPE_SALT2;
|
||
+ } else {
|
||
+ state->session_key[0] = MPPE_SALT0;
|
||
+ }
|
||
+ }
|
||
+ arc4_setkey(state, state->session_key, state->keylen);
|
||
+}
|
||
+
|
||
+/* increase 12-bit coherency counter */
|
||
+static inline void
|
||
+mppe_increase_ccount(struct ppp_mppe_state *state)
|
||
+{
|
||
+ state->ccount = (state->ccount + 1) & MPPE_MAX_CCOUNT;
|
||
+ if (state->mppe) {
|
||
+ if (state->stateless) {
|
||
+ mppe_change_key(state, 0);
|
||
+ state->nextflushed = 1;
|
||
+ } else {
|
||
+ if ((state->ccount & 0xff) == 0xff) {
|
||
+ mppe_change_key(state, 0);
|
||
+ }
|
||
+ }
|
||
+ }
|
||
+}
|
||
+
|
||
+/* allocate space for a MPPE/MPPC (de)compressor. */
|
||
+/* comp != 0 -> init compressor */
|
||
+/* comp = 0 -> init decompressor */
|
||
+static void *
|
||
+mppe_alloc(unsigned char *options, int opt_len, int comp)
|
||
+{
|
||
+ struct ppp_mppe_state *state;
|
||
+ unsigned int digestsize;
|
||
+ u8* fname;
|
||
+
|
||
+ fname = comp ? "mppe_comp_alloc" : "mppe_decomp_alloc";
|
||
+
|
||
+ /*
|
||
+ * Hack warning - additionally to the standard MPPC/MPPE configuration
|
||
+ * options, pppd passes to the (de)copressor 8 or 16 byte session key.
|
||
+ * Therefore options[1] contains MPPC/MPPE configuration option length
|
||
+ * (CILEN_MPPE = 6), but the real options length, depending on the key
|
||
+ * length, is 6+8 or 6+16.
|
||
+ */
|
||
+ if (opt_len < CILEN_MPPE) {
|
||
+ printk(KERN_WARNING "%s: wrong options length: %u\n", fname, opt_len);
|
||
+ return NULL;
|
||
+ }
|
||
+
|
||
+ if (options[0] != CI_MPPE || options[1] != CILEN_MPPE ||
|
||
+ (options[2] & ~MPPE_STATELESS) != 0 ||
|
||
+ options[3] != 0 || options[4] != 0 ||
|
||
+ (options[5] & ~(MPPE_128BIT|MPPE_56BIT|MPPE_40BIT|MPPE_MPPC)) != 0 ||
|
||
+ (options[5] & (MPPE_128BIT|MPPE_56BIT|MPPE_40BIT|MPPE_MPPC)) == 0) {
|
||
+ printk(KERN_WARNING "%s: options rejected: o[0]=%02x, o[1]=%02x, "
|
||
+ "o[2]=%02x, o[3]=%02x, o[4]=%02x, o[5]=%02x\n", fname, options[0],
|
||
+ options[1], options[2], options[3], options[4], options[5]);
|
||
+ return NULL;
|
||
+ }
|
||
+
|
||
+ state = (struct ppp_mppe_state *)kmalloc(sizeof(*state), GFP_KERNEL);
|
||
+ if (state == NULL) {
|
||
+ printk(KERN_ERR "%s: cannot allocate space for %scompressor\n", fname,
|
||
+ comp ? "" : "de");
|
||
+ return NULL;
|
||
+ }
|
||
+ memset(state, 0, sizeof(struct ppp_mppe_state));
|
||
+
|
||
+ state->mppc = options[5] & MPPE_MPPC; /* Do we use MPPC? */
|
||
+ state->mppe = options[5] & (MPPE_128BIT | MPPE_56BIT |
|
||
+ MPPE_40BIT); /* Do we use MPPE? */
|
||
+
|
||
+ if (state->mppc) {
|
||
+ /* allocate MPPC history */
|
||
+ state->hist = (u8*)vmalloc(2*MPPE_HIST_LEN*sizeof(u8));
|
||
+ if (state->hist == NULL) {
|
||
+ kfree(state);
|
||
+ printk(KERN_ERR "%s: cannot allocate space for MPPC history\n",
|
||
+ fname);
|
||
+ return NULL;
|
||
+ }
|
||
+
|
||
+ /* allocate hashtable for MPPC compressor */
|
||
+ if (comp) {
|
||
+ state->hash = (u16*)vmalloc(MPPE_HIST_LEN*sizeof(u16));
|
||
+ if (state->hash == NULL) {
|
||
+ vfree(state->hist);
|
||
+ kfree(state);
|
||
+ printk(KERN_ERR "%s: cannot allocate space for MPPC history\n",
|
||
+ fname);
|
||
+ return NULL;
|
||
+ }
|
||
+ }
|
||
+ }
|
||
+
|
||
+ if (state->mppe) { /* specific for MPPE */
|
||
+ /* Load ARC4 algorithm */
|
||
+ state->arc4_tfm = crypto_alloc_tfm("arc4", 0);
|
||
+ if (state->arc4_tfm == NULL) {
|
||
+ if (state->mppc) {
|
||
+ vfree(state->hash);
|
||
+ if (comp)
|
||
+ vfree(state->hist);
|
||
+ }
|
||
+ kfree(state);
|
||
+ printk(KERN_ERR "%s: cannot load ARC4 module\n", fname);
|
||
+ return NULL;
|
||
+ }
|
||
+
|
||
+ /* Load SHA1 algorithm */
|
||
+ state->sha1_tfm = crypto_alloc_tfm("sha1", 0);
|
||
+ if (state->sha1_tfm == NULL) {
|
||
+ crypto_free_tfm(state->arc4_tfm);
|
||
+ if (state->mppc) {
|
||
+ vfree(state->hash);
|
||
+ if (comp)
|
||
+ vfree(state->hist);
|
||
+ }
|
||
+ kfree(state);
|
||
+ printk(KERN_ERR "%s: cannot load SHA1 module\n", fname);
|
||
+ return NULL;
|
||
+ }
|
||
+
|
||
+ digestsize = crypto_tfm_alg_digestsize(state->sha1_tfm);
|
||
+ if (digestsize < MPPE_MAX_KEY_LEN) {
|
||
+ crypto_free_tfm(state->sha1_tfm);
|
||
+ crypto_free_tfm(state->arc4_tfm);
|
||
+ if (state->mppc) {
|
||
+ vfree(state->hash);
|
||
+ if (comp)
|
||
+ vfree(state->hist);
|
||
+ }
|
||
+ kfree(state);
|
||
+ printk(KERN_ERR "%s: CryptoAPI SHA1 digest size too small\n", fname);
|
||
+ }
|
||
+
|
||
+ state->sha1_digest = kmalloc(digestsize, GFP_KERNEL);
|
||
+ if (!state->sha1_digest) {
|
||
+ crypto_free_tfm(state->sha1_tfm);
|
||
+ crypto_free_tfm(state->arc4_tfm);
|
||
+ if (state->mppc) {
|
||
+ vfree(state->hash);
|
||
+ if (comp)
|
||
+ vfree(state->hist);
|
||
+ }
|
||
+ kfree(state);
|
||
+ printk(KERN_ERR "%s: cannot allocate space for SHA1 digest\n", fname);
|
||
+ }
|
||
+
|
||
+ memcpy(state->master_key, options+CILEN_MPPE, MPPE_MAX_KEY_LEN);
|
||
+ memcpy(state->session_key, state->master_key, MPPE_MAX_KEY_LEN);
|
||
+ /* initial key generation is done in mppe_init() */
|
||
+ }
|
||
+
|
||
+ MOD_INC_USE_COUNT;
|
||
+
|
||
+ return (void *) state;
|
||
+}
|
||
+
|
||
+static void *
|
||
+mppe_comp_alloc(unsigned char *options, int opt_len)
|
||
+{
|
||
+ return mppe_alloc(options, opt_len, 1);
|
||
+}
|
||
+
|
||
+static void *
|
||
+mppe_decomp_alloc(unsigned char *options, int opt_len)
|
||
+{
|
||
+ return mppe_alloc(options, opt_len, 0);
|
||
+}
|
||
+
|
||
+/* cleanup the (de)compressor */
|
||
+static void
|
||
+mppe_comp_free(void *arg)
|
||
+{
|
||
+ struct ppp_mppe_state *state = (struct ppp_mppe_state *) arg;
|
||
+
|
||
+ if (state != NULL) {
|
||
+ if (state->mppe) {
|
||
+ if (state->sha1_tfm != NULL)
|
||
+ crypto_free_tfm(state->sha1_tfm);
|
||
+ if (state->arc4_tfm != NULL)
|
||
+ crypto_free_tfm(state->arc4_tfm);
|
||
+ }
|
||
+ if (state->hist != NULL)
|
||
+ vfree(state->hist);
|
||
+ if (state->hash != NULL)
|
||
+ vfree(state->hash);
|
||
+ kfree(state);
|
||
+ }
|
||
+
|
||
+ MOD_DEC_USE_COUNT;
|
||
+}
|
||
+
|
||
+/* init MPPC/MPPE (de)compresor */
|
||
+/* comp != 0 -> init compressor */
|
||
+/* comp = 0 -> init decompressor */
|
||
+static int
|
||
+mppe_init(void *arg, unsigned char *options, int opt_len, int unit,
|
||
+ int hdrlen, int mru, int debug, int comp)
|
||
+{
|
||
+ struct ppp_mppe_state *state = (struct ppp_mppe_state *) arg;
|
||
+ u8* fname;
|
||
+
|
||
+ fname = comp ? "mppe_comp_init" : "mppe_decomp_init";
|
||
+
|
||
+ if (opt_len < CILEN_MPPE) {
|
||
+ if (debug)
|
||
+ printk(KERN_WARNING "%s: wrong options length: %u\n",
|
||
+ fname, opt_len);
|
||
+ return 0;
|
||
+ }
|
||
+
|
||
+ if (options[0] != CI_MPPE || options[1] != CILEN_MPPE ||
|
||
+ (options[2] & ~MPPE_STATELESS) != 0 ||
|
||
+ options[3] != 0 || options[4] != 0 ||
|
||
+ (options[5] & ~(MPPE_56BIT|MPPE_128BIT|MPPE_40BIT|MPPE_MPPC)) != 0 ||
|
||
+ (options[5] & (MPPE_56BIT|MPPE_128BIT|MPPE_40BIT|MPPE_MPPC)) == 0) {
|
||
+ if (debug)
|
||
+ printk(KERN_WARNING "%s: options rejected: o[0]=%02x, o[1]=%02x, "
|
||
+ "o[2]=%02x, o[3]=%02x, o[4]=%02x, o[5]=%02x\n", fname,
|
||
+ options[0], options[1], options[2], options[3], options[4],
|
||
+ options[5]);
|
||
+ return 0;
|
||
+ }
|
||
+
|
||
+ if ((options[5] & ~MPPE_MPPC) != MPPE_128BIT &&
|
||
+ (options[5] & ~MPPE_MPPC) != MPPE_56BIT &&
|
||
+ (options[5] & ~MPPE_MPPC) != MPPE_40BIT &&
|
||
+ (options[5] & MPPE_MPPC) != MPPE_MPPC) {
|
||
+ if (debug)
|
||
+ printk(KERN_WARNING "%s: don't know what to do: o[5]=%02x\n",
|
||
+ fname, options[5]);
|
||
+ return 0;
|
||
+ }
|
||
+
|
||
+ state->mppc = options[5] & MPPE_MPPC; /* Do we use MPPC? */
|
||
+ state->mppe = options[5] & (MPPE_128BIT | MPPE_56BIT |
|
||
+ MPPE_40BIT); /* Do we use MPPE? */
|
||
+ state->stateless = options[2] & MPPE_STATELESS; /* Do we use stateless mode? */
|
||
+
|
||
+ switch (state->mppe) {
|
||
+ case MPPE_40BIT: /* 40 bit key */
|
||
+ state->keylen = 8;
|
||
+ state->bitkeylen = 40;
|
||
+ break;
|
||
+ case MPPE_56BIT: /* 56 bit key */
|
||
+ state->keylen = 8;
|
||
+ state->bitkeylen = 56;
|
||
+ break;
|
||
+ case MPPE_128BIT: /* 128 bit key */
|
||
+ state->keylen = 16;
|
||
+ state->bitkeylen = 128;
|
||
+ break;
|
||
+ default:
|
||
+ state->keylen = 0;
|
||
+ state->bitkeylen = 0;
|
||
+ }
|
||
+
|
||
+ state->ccount = MPPE_MAX_CCOUNT;
|
||
+ state->bits = 0;
|
||
+ state->unit = unit;
|
||
+ state->debug = debug;
|
||
+ state->histptr = MPPE_HIST_LEN;
|
||
+ if (state->mppc) { /* reset history if MPPC was negotiated */
|
||
+ memset(state->hist, 0, 2*MPPE_HIST_LEN*sizeof(u8));
|
||
+ }
|
||
+
|
||
+ if (state->mppe) { /* generate initial session keys */
|
||
+ mppe_change_key(state, 1);
|
||
+ }
|
||
+
|
||
+ if (comp) { /* specific for compressor */
|
||
+ state->nextflushed = 1;
|
||
+ } else { /* specific for decompressor */
|
||
+ state->mru = mru;
|
||
+ state->flushexpected = 1;
|
||
+ }
|
||
+
|
||
+ return 1;
|
||
+}
|
||
+
|
||
+static int
|
||
+mppe_comp_init(void *arg, unsigned char *options, int opt_len, int unit,
|
||
+ int hdrlen, int debug)
|
||
+{
|
||
+ return mppe_init(arg, options, opt_len, unit, hdrlen, 0, debug, 1);
|
||
+}
|
||
+
|
||
+
|
||
+static int
|
||
+mppe_decomp_init(void *arg, unsigned char *options, int opt_len, int unit,
|
||
+ int hdrlen, int mru, int debug)
|
||
+{
|
||
+ return mppe_init(arg, options, opt_len, unit, hdrlen, mru, debug, 0);
|
||
+}
|
||
+
|
||
+static void
|
||
+mppe_comp_reset(void *arg)
|
||
+{
|
||
+ struct ppp_mppe_state *state = (struct ppp_mppe_state *)arg;
|
||
+
|
||
+ if (state->debug)
|
||
+ printk(KERN_DEBUG "%s%d: resetting MPPC/MPPE compressor\n",
|
||
+ __FUNCTION__, state->unit);
|
||
+
|
||
+ state->nextflushed = 1;
|
||
+ if (state->mppe)
|
||
+ arc4_setkey(state, state->session_key, state->keylen);
|
||
+}
|
||
+
|
||
+static void
|
||
+mppe_decomp_reset(void *arg)
|
||
+{
|
||
+ /* When MPPC/MPPE is in use, we shouldn't receive any CCP Reset-Ack.
|
||
+ But when we receive such a packet, we just ignore it. */
|
||
+ return;
|
||
+}
|
||
+
|
||
+static void
|
||
+mppe_stats(void *arg, struct compstat *stats)
|
||
+{
|
||
+ struct ppp_mppe_state *state = (struct ppp_mppe_state *)arg;
|
||
+
|
||
+ *stats = state->stats;
|
||
+}
|
||
+
|
||
+/***************************/
|
||
+/**** Compression stuff ****/
|
||
+/***************************/
|
||
+/* inserts 1 to 8 bits into the output buffer */
|
||
+static inline void putbits8(u8 *buf, u32 val, const u32 n, u32 *i, u32 *l)
|
||
+{
|
||
+ buf += *i;
|
||
+ if (*l >= n) {
|
||
+ *l = (*l) - n;
|
||
+ val <<= *l;
|
||
+ *buf = *buf | (val & 0xff);
|
||
+ if (*l == 0) {
|
||
+ *l = 8;
|
||
+ (*i)++;
|
||
+ *(++buf) = 0;
|
||
+ }
|
||
+ } else {
|
||
+ (*i)++;
|
||
+ *l = 8 - n + (*l);
|
||
+ val <<= *l;
|
||
+ *buf = *buf | ((val >> 8) & 0xff);
|
||
+ *(++buf) = val & 0xff;
|
||
+ }
|
||
+}
|
||
+
|
||
+/* inserts 9 to 16 bits into the output buffer */
|
||
+static inline void putbits16(u8 *buf, u32 val, const u32 n, u32 *i, u32 *l)
|
||
+{
|
||
+ buf += *i;
|
||
+ if (*l >= n - 8) {
|
||
+ (*i)++;
|
||
+ *l = 8 - n + (*l);
|
||
+ val <<= *l;
|
||
+ *buf = *buf | ((val >> 8) & 0xff);
|
||
+ *(++buf) = val & 0xff;
|
||
+ if (*l == 0) {
|
||
+ *l = 8;
|
||
+ (*i)++;
|
||
+ *(++buf) = 0;
|
||
+ }
|
||
+ } else {
|
||
+ (*i)++; (*i)++;
|
||
+ *l = 16 - n + (*l);
|
||
+ val <<= *l;
|
||
+ *buf = *buf | ((val >> 16) & 0xff);
|
||
+ *(++buf) = (val >> 8) & 0xff;
|
||
+ *(++buf) = val & 0xff;
|
||
+ }
|
||
+}
|
||
+
|
||
+/* inserts 17 to 24 bits into the output buffer */
|
||
+static inline void putbits24(u8 *buf, u32 val, const u32 n, u32 *i, u32 *l)
|
||
+{
|
||
+ buf += *i;
|
||
+ if (*l >= n - 16) {
|
||
+ (*i)++; (*i)++;
|
||
+ *l = 16 - n + (*l);
|
||
+ val <<= *l;
|
||
+ *buf = *buf | ((val >> 16) & 0xff);
|
||
+ *(++buf) = (val >> 8) & 0xff;
|
||
+ *(++buf) = val & 0xff;
|
||
+ if (*l == 0) {
|
||
+ *l = 8;
|
||
+ (*i)++;
|
||
+ *(++buf) = 0;
|
||
+ }
|
||
+ } else {
|
||
+ (*i)++; (*i)++; (*i)++;
|
||
+ *l = 24 - n + (*l);
|
||
+ val <<= *l;
|
||
+ *buf = *buf | ((val >> 24) & 0xff);
|
||
+ *(++buf) = (val >> 16) & 0xff;
|
||
+ *(++buf) = (val >> 8) & 0xff;
|
||
+ *(++buf) = val & 0xff;
|
||
+ }
|
||
+}
|
||
+
|
||
+static int
|
||
+mppc_compress(struct ppp_mppe_state *state, unsigned char *ibuf,
|
||
+ unsigned char *obuf, int isize, int osize)
|
||
+{
|
||
+ u32 olen, off, len, idx, i, l;
|
||
+ u8 *hist, *sbuf, *p, *q, *r, *s;
|
||
+
|
||
+ /*
|
||
+ At this point, to avoid possible buffer overflow caused by packet
|
||
+ expansion during/after compression, we should make sure that
|
||
+ osize >= (((isize*9)/8)+1)+2, but we don't do that because in
|
||
+ ppp_generic.c we simply allocate bigger obuf.
|
||
+
|
||
+ Maximum MPPC packet expansion is 12.5%. This is the worst case when
|
||
+ all octets in the input buffer are >= 0x80 and we cannot find any
|
||
+ repeated tokens. Additionally we have to reserve 2 bytes for MPPE/MPPC
|
||
+ status bits and coherency counter.
|
||
+ */
|
||
+
|
||
+ hist = state->hist + MPPE_HIST_LEN;
|
||
+ /* check if there is enough room at the end of the history */
|
||
+ if (state->histptr + isize >= 2*MPPE_HIST_LEN) {
|
||
+ state->bits |= MPPE_BIT_RESET;
|
||
+ state->histptr = MPPE_HIST_LEN;
|
||
+ memcpy(state->hist, hist, MPPE_HIST_LEN);
|
||
+ }
|
||
+ /* add packet to the history; isize must be <= MPPE_HIST_LEN */
|
||
+ sbuf = state->hist + state->histptr;
|
||
+ memcpy(sbuf, ibuf, isize);
|
||
+ state->histptr += isize;
|
||
+
|
||
+ /* compress data */
|
||
+ r = sbuf + isize;
|
||
+ *obuf = olen = i = 0;
|
||
+ l = 8;
|
||
+ while (i < isize - 2) {
|
||
+ s = q = sbuf + i;
|
||
+ idx = ((40543*((((s[0]<<4)^s[1])<<4)^s[2]))>>4) & 0x1fff;
|
||
+ p = hist + state->hash[idx];
|
||
+ state->hash[idx] = (u16) (s - hist);
|
||
+ off = s - p;
|
||
+ if (off > MPPE_HIST_LEN - 1 || off < 1 || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++) {
|
||
+ /* no match found; encode literal byte */
|
||
+ if (ibuf[i] < 0x80) { /* literal byte < 0x80 */
|
||
+ putbits8(obuf, (u32) ibuf[i], 8, &olen, &l);
|
||
+ } else { /* literal byte >= 0x80 */
|
||
+ putbits16(obuf, (u32) (0x100|(ibuf[i]&0x7f)), 9, &olen, &l);
|
||
+ }
|
||
+ ++i;
|
||
+ continue;
|
||
+ }
|
||
+ if (r - q >= 64) {
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++ || *p++ != *s++ || *p++ != *s++ || *p++ != *s++ ||
|
||
+ *p++ != *s++;
|
||
+ if (s - q == 64) {
|
||
+ p--; s--;
|
||
+ while((*p++ == *s++) && (s < r) && (p < q));
|
||
+ }
|
||
+ } else {
|
||
+ while((*p++ == *s++) && (s < r) && (p < q));
|
||
+ }
|
||
+ len = s - q - 1;
|
||
+ i += len;
|
||
+
|
||
+ /* at least 3 character match found; code data */
|
||
+ /* encode offset */
|
||
+ if (off < 64) { /* 10-bit offset; 0 <= offset < 64 */
|
||
+ putbits16(obuf, 0x3c0|off, 10, &olen, &l);
|
||
+ } else if (off < 320) { /* 12-bit offset; 64 <= offset < 320 */
|
||
+ putbits16(obuf, 0xe00|(off-64), 12, &olen, &l);
|
||
+ } else if (off < 8192) { /* 16-bit offset; 320 <= offset < 8192 */
|
||
+ putbits16(obuf, 0xc000|(off-320), 16, &olen, &l);
|
||
+ } else {
|
||
+ /* This shouldn't happen; we return 0 what means "packet expands",
|
||
+ and we send packet uncompressed. */
|
||
+ if (state->debug)
|
||
+ printk(KERN_DEBUG "%s%d: wrong offset value: %d\n",
|
||
+ __FUNCTION__, state->unit, off);
|
||
+ return 0;
|
||
+ }
|
||
+ /* encode length of match */
|
||
+ if (len < 4) { /* length = 3 */
|
||
+ putbits8(obuf, 0, 1, &olen, &l);
|
||
+ } else if (len < 8) { /* 4 <= length < 8 */
|
||
+ putbits8(obuf, 0x08|(len&0x03), 4, &olen, &l);
|
||
+ } else if (len < 16) { /* 8 <= length < 16 */
|
||
+ putbits8(obuf, 0x30|(len&0x07), 6, &olen, &l);
|
||
+ } else if (len < 32) { /* 16 <= length < 32 */
|
||
+ putbits8(obuf, 0xe0|(len&0x0f), 8, &olen, &l);
|
||
+ } else if (len < 64) { /* 32 <= length < 64 */
|
||
+ putbits16(obuf, 0x3c0|(len&0x1f), 10, &olen, &l);
|
||
+ } else if (len < 128) { /* 64 <= length < 128 */
|
||
+ putbits16(obuf, 0xf80|(len&0x3f), 12, &olen, &l);
|
||
+ } else if (len < 256) { /* 128 <= length < 256 */
|
||
+ putbits16(obuf, 0x3f00|(len&0x7f), 14, &olen, &l);
|
||
+ } else if (len < 512) { /* 256 <= length < 512 */
|
||
+ putbits16(obuf, 0xfe00|(len&0xff), 16, &olen, &l);
|
||
+ } else if (len < 1024) { /* 512 <= length < 1024 */
|
||
+ putbits24(obuf, 0x3fc00|(len&0x1ff), 18, &olen, &l);
|
||
+ } else if (len < 2048) { /* 1024 <= length < 2048 */
|
||
+ putbits24(obuf, 0xff800|(len&0x3ff), 20, &olen, &l);
|
||
+ } else if (len < 4096) { /* 2048 <= length < 4096 */
|
||
+ putbits24(obuf, 0x3ff000|(len&0x7ff), 22, &olen, &l);
|
||
+ } else if (len < 8192) { /* 4096 <= length < 8192 */
|
||
+ putbits24(obuf, 0xffe000|(len&0xfff), 24, &olen, &l);
|
||
+ } else {
|
||
+ /* This shouldn't happen; we return 0 what means "packet expands",
|
||
+ and send packet uncompressed. */
|
||
+ if (state->debug)
|
||
+ printk(KERN_DEBUG "%s%d: wrong length of match value: %d\n",
|
||
+ __FUNCTION__, state->unit, len);
|
||
+ return 0;
|
||
+ }
|
||
+ }
|
||
+
|
||
+ /* Add remaining octets to the output */
|
||
+ while(isize - i > 0) {
|
||
+ if (ibuf[i] < 0x80) { /* literal byte < 0x80 */
|
||
+ putbits8(obuf, (u32) ibuf[i++], 8, &olen, &l);
|
||
+ } else { /* literal byte >= 0x80 */
|
||
+ putbits16(obuf, (u32) (0x100|(ibuf[i++]&0x7f)), 9, &olen, &l);
|
||
+ }
|
||
+ }
|
||
+ /* Reset unused bits of the last output octet */
|
||
+ if ((l != 0) && (l != 8)) {
|
||
+ putbits8(obuf, 0, l, &olen, &l);
|
||
+ }
|
||
+
|
||
+ return (int) olen;
|
||
+}
|
||
+
|
||
+int
|
||
+mppe_compress(void *arg, unsigned char *ibuf, unsigned char *obuf,
|
||
+ int isize, int osize)
|
||
+{
|
||
+ struct ppp_mppe_state *state = (struct ppp_mppe_state *) arg;
|
||
+ int proto, olen, complen, off;
|
||
+ unsigned char *wptr;
|
||
+
|
||
+ /* Check that the protocol is in the range we handle. */
|
||
+ proto = PPP_PROTOCOL(ibuf);
|
||
+ if (proto < 0x0021 || proto > 0x00fa)
|
||
+ return 0;
|
||
+
|
||
+ wptr = obuf;
|
||
+ /* Copy over the PPP header */
|
||
+ wptr[0] = PPP_ADDRESS(ibuf);
|
||
+ wptr[1] = PPP_CONTROL(ibuf);
|
||
+ wptr[2] = PPP_COMP >> 8;
|
||
+ wptr[3] = PPP_COMP;
|
||
+ wptr += PPP_HDRLEN + (MPPE_OVHD / 2); /* Leave two octets for MPPE/MPPC bits */
|
||
+
|
||
+ /*
|
||
+ * In ver. 0.99 protocol field was compressed. Deflate and BSD compress
|
||
+ * do PFC before actual compression, RCF2118 and RFC3078 are not precise
|
||
+ * on this topic so I decided to do PFC. Unfortunately this change caused
|
||
+ * incompatibility with older/other MPPE/MPPC modules. I have received
|
||
+ * a lot of complaints from unexperienced users so I have decided to revert
|
||
+ * to previous state, i.e. the protocol field is sent uncompressed now.
|
||
+ * Although this may be changed in the future.
|
||
+ *
|
||
+ * Receiving side (mppe_decompress()) still accepts packets with compressed
|
||
+ * and uncompressed protocol field so you shouldn't get "Unsupported protocol
|
||
+ * 0x2145 received" messages anymore.
|
||
+ */
|
||
+ //off = (proto > 0xff) ? 2 : 3; /* PFC - skip first protocol byte if 0 */
|
||
+ off = 2;
|
||
+
|
||
+ ibuf += off;
|
||
+
|
||
+ mppe_increase_ccount(state);
|
||
+
|
||
+ if (state->nextflushed) {
|
||
+ state->bits |= MPPE_BIT_FLUSHED;
|
||
+ state->nextflushed = 0;
|
||
+ if (state->mppe && !state->stateless) {
|
||
+ /*
|
||
+ * If this is the flag packet, the key has been already changed in
|
||
+ * mppe_increase_ccount() so we dont't do it once again.
|
||
+ */
|
||
+ if ((state->ccount & 0xff) != 0xff) {
|
||
+ arc4_setkey(state, state->session_key, state->keylen);
|
||
+ }
|
||
+ }
|
||
+ if (state->mppc) { /* reset history */
|
||
+ state->bits |= MPPE_BIT_RESET;
|
||
+ state->histptr = MPPE_HIST_LEN;
|
||
+ memset(state->hist + MPPE_HIST_LEN, 0, MPPE_HIST_LEN*sizeof(u8));
|
||
+ }
|
||
+ }
|
||
+
|
||
+ if (state->mppc && !state->mppe) { /* Do only compression */
|
||
+ complen = mppc_compress(state, ibuf, wptr, isize - off,
|
||
+ osize - PPP_HDRLEN - (MPPE_OVHD / 2));
|
||
+ /*
|
||
+ * TODO: Implement an heuristics to handle packet expansion in a smart
|
||
+ * way. Now, when a packet expands, we send it as uncompressed and
|
||
+ * when next packet is sent we have to reset compressor's history.
|
||
+ * Maybe it would be better to send such packet as compressed in order
|
||
+ * to keep history's continuity.
|
||
+ */
|
||
+ if ((complen > isize) || (complen > osize - PPP_HDRLEN) ||
|
||
+ (complen == 0)) {
|
||
+ /* packet expands */
|
||
+ state->nextflushed = 1;
|
||
+ memcpy(wptr, ibuf, isize - off);
|
||
+ olen = isize - (off - 2) + MPPE_OVHD;
|
||
+ (state->stats).inc_bytes += olen;
|
||
+ (state->stats).inc_packets++;
|
||
+ } else {
|
||
+ state->bits |= MPPE_BIT_COMP;
|
||
+ olen = complen + PPP_HDRLEN + (MPPE_OVHD / 2);
|
||
+ (state->stats).comp_bytes += olen;
|
||
+ (state->stats).comp_packets++;
|
||
+ }
|
||
+ } else { /* Do encryption with or without compression */
|
||
+ state->bits |= MPPE_BIT_ENCRYPTED;
|
||
+ if (!state->mppc && state->mppe) { /* Do only encryption */
|
||
+ /* read from ibuf, write to wptr, adjust for PPP_HDRLEN */
|
||
+ arc4_encrypt(state, ibuf, isize - off, wptr);
|
||
+ olen = isize - (off - 2) + MPPE_OVHD;
|
||
+ (state->stats).inc_bytes += olen;
|
||
+ (state->stats).inc_packets++;
|
||
+ } else { /* Do compression and then encryption - RFC3078 */
|
||
+ complen = mppc_compress(state, ibuf, wptr, isize - off,
|
||
+ osize - PPP_HDRLEN - (MPPE_OVHD / 2));
|
||
+ /*
|
||
+ * TODO: Implement an heuristics to handle packet expansion in a smart
|
||
+ * way. Now, when a packet expands, we send it as uncompressed and
|
||
+ * when next packet is sent we have to reset compressor's history.
|
||
+ * Maybe it would be good to send such packet as compressed in order
|
||
+ * to keep history's continuity.
|
||
+ */
|
||
+ if ((complen > isize) || (complen > osize - PPP_HDRLEN) ||
|
||
+ (complen == 0)) {
|
||
+ /* packet expands */
|
||
+ state->nextflushed = 1;
|
||
+ arc4_encrypt(state, ibuf, isize - off, wptr);
|
||
+ olen = isize - (off - 2) + MPPE_OVHD;
|
||
+ (state->stats).inc_bytes += olen;
|
||
+ (state->stats).inc_packets++;
|
||
+ } else {
|
||
+ state->bits |= MPPE_BIT_COMP;
|
||
+ /* Hack warning !!! RC4 implementation which we use does
|
||
+ encryption "in place" - it means that input and output
|
||
+ buffers can be *the same* memory area. Therefore we don't
|
||
+ need to use a temporary buffer. But be careful - other
|
||
+ implementations don't have to be so nice.
|
||
+ I used to use ibuf as temporary buffer here, but it led
|
||
+ packet sniffers into error. Thanks to Wilfried Weissmann
|
||
+ for pointing that. */
|
||
+ arc4_encrypt(state, wptr, complen, wptr);
|
||
+ olen = complen + PPP_HDRLEN + (MPPE_OVHD / 2);
|
||
+ (state->stats).comp_bytes += olen;
|
||
+ (state->stats).comp_packets++;
|
||
+ }
|
||
+ }
|
||
+ }
|
||
+
|
||
+ /* write status bits and coherency counter into the output buffer */
|
||
+ wptr = obuf + PPP_HDRLEN;
|
||
+ wptr[0] = MPPE_CTRLHI(state);
|
||
+ wptr[1] = MPPE_CTRLLO(state);
|
||
+
|
||
+ state->bits = 0;
|
||
+
|
||
+ (state->stats).unc_bytes += isize;
|
||
+ (state->stats).unc_packets++;
|
||
+
|
||
+ return olen;
|
||
+}
|
||
+
|
||
+/***************************/
|
||
+/*** Decompression stuff ***/
|
||
+/***************************/
|
||
+static inline u32 getbits(const u8 *buf, const u32 n, u32 *i, u32 *l)
|
||
+{
|
||
+ static const u32 m[] = {0x00, 0x01, 0x03, 0x07, 0x0f, 0x1f, 0x3f, 0x7f, 0xff};
|
||
+ u32 res, ol;
|
||
+
|
||
+ ol = *l;
|
||
+ if (*l >= n) {
|
||
+ *l = (*l) - n;
|
||
+ res = (buf[*i] & m[ol]) >> (*l);
|
||
+ if (*l == 0) {
|
||
+ *l = 8;
|
||
+ (*i)++;
|
||
+ }
|
||
+ } else {
|
||
+ *l = 8 - n + (*l);
|
||
+ res = (buf[(*i)++] & m[ol]) << 8;
|
||
+ res = (res | buf[*i]) >> (*l);
|
||
+ }
|
||
+
|
||
+ return res;
|
||
+}
|
||
+
|
||
+static inline u32 getbyte(const u8 *buf, const u32 i, const u32 l)
|
||
+{
|
||
+ if (l == 8) {
|
||
+ return buf[i];
|
||
+ } else {
|
||
+ return (((buf[i] << 8) | buf[i+1]) >> l) & 0xff;
|
||
+ }
|
||
+}
|
||
+
|
||
+static inline void lamecopy(u8 *dst, u8 *src, u32 len)
|
||
+{
|
||
+ while (len--)
|
||
+ *dst++ = *src++;
|
||
+}
|
||
+
|
||
+static int
|
||
+mppc_decompress(struct ppp_mppe_state *state, unsigned char *ibuf,
|
||
+ unsigned char *obuf, int isize, int osize)
|
||
+{
|
||
+ u32 olen, off, len, bits, val, sig, i, l;
|
||
+ u8 *history, *s;
|
||
+
|
||
+ history = state->hist + state->histptr;
|
||
+ olen = len = i = 0;
|
||
+ l = 8;
|
||
+ bits = isize * 8;
|
||
+ while (bits >= 8) {
|
||
+ val = getbyte(ibuf, i++, l);
|
||
+ if (val < 0x80) { /* literal byte < 0x80 */
|
||
+ if (state->histptr < 2*MPPE_HIST_LEN) {
|
||
+ /* copy uncompressed byte to the history */
|
||
+ (state->hist)[(state->histptr)++] = (u8) val;
|
||
+ } else {
|
||
+ /* buffer overflow; drop packet */
|
||
+ if (state->debug)
|
||
+ printk(KERN_ERR "%s%d: trying to write outside history "
|
||
+ "buffer\n", __FUNCTION__, state->unit);
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ olen++;
|
||
+ bits -= 8;
|
||
+ continue;
|
||
+ }
|
||
+
|
||
+ sig = val & 0xc0;
|
||
+ if (sig == 0x80) { /* literal byte >= 0x80 */
|
||
+ if (state->histptr < 2*MPPE_HIST_LEN) {
|
||
+ /* copy uncompressed byte to the history */
|
||
+ (state->hist)[(state->histptr)++] =
|
||
+ (u8) (0x80|((val&0x3f)<<1)|getbits(ibuf, 1 , &i ,&l));
|
||
+ } else {
|
||
+ /* buffer overflow; drop packet */
|
||
+ if (state->debug)
|
||
+ printk(KERN_ERR "%s%d: trying to write outside history "
|
||
+ "buffer\n", __FUNCTION__, state->unit);
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ olen++;
|
||
+ bits -= 9;
|
||
+ continue;
|
||
+ }
|
||
+
|
||
+ /* Not a literal byte so it must be an (offset,length) pair */
|
||
+ /* decode offset */
|
||
+ sig = val & 0xf0;
|
||
+ if (sig == 0xf0) { /* 10-bit offset; 0 <= offset < 64 */
|
||
+ off = (((val&0x0f)<<2)|getbits(ibuf, 2 , &i ,&l));
|
||
+ bits -= 10;
|
||
+ } else {
|
||
+ if (sig == 0xe0) { /* 12-bit offset; 64 <= offset < 320 */
|
||
+ off = ((((val&0x0f)<<4)|getbits(ibuf, 4 , &i ,&l))+64);
|
||
+ bits -= 12;
|
||
+ } else {
|
||
+ if ((sig&0xe0) == 0xc0) {/* 16-bit offset; 320 <= offset < 8192 */
|
||
+ off = ((((val&0x1f)<<8)|getbyte(ibuf, i++, l))+320);
|
||
+ bits -= 16;
|
||
+ if (off > MPPE_HIST_LEN - 1) {
|
||
+ if (state->debug)
|
||
+ printk(KERN_DEBUG "%s%d: too big offset value: %d\n",
|
||
+ __FUNCTION__, state->unit, off);
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ } else { /* this shouldn't happen */
|
||
+ if (state->debug)
|
||
+ printk(KERN_DEBUG "%s%d: cannot decode offset value\n",
|
||
+ __FUNCTION__, state->unit);
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ }
|
||
+ }
|
||
+ /* decode length of match */
|
||
+ val = getbyte(ibuf, i, l);
|
||
+ if ((val & 0x80) == 0x00) { /* len = 3 */
|
||
+ len = 3;
|
||
+ bits--;
|
||
+ getbits(ibuf, 1 , &i ,&l);
|
||
+ } else if ((val & 0xc0) == 0x80) { /* 4 <= len < 8 */
|
||
+ len = 0x04 | ((val>>4) & 0x03);
|
||
+ bits -= 4;
|
||
+ getbits(ibuf, 4 , &i ,&l);
|
||
+ } else if ((val & 0xe0) == 0xc0) { /* 8 <= len < 16 */
|
||
+ len = 0x08 | ((val>>2) & 0x07);
|
||
+ bits -= 6;
|
||
+ getbits(ibuf, 6 , &i ,&l);
|
||
+ } else if ((val & 0xf0) == 0xe0) { /* 16 <= len < 32 */
|
||
+ len = 0x10 | (val & 0x0f);
|
||
+ bits -= 8;
|
||
+ i++;
|
||
+ } else {
|
||
+ bits -= 8;
|
||
+ val = (val << 8) | getbyte(ibuf, ++i, l);
|
||
+ if ((val & 0xf800) == 0xf000) { /* 32 <= len < 64 */
|
||
+ len = 0x0020 | ((val >> 6) & 0x001f);
|
||
+ bits -= 2;
|
||
+ getbits(ibuf, 2 , &i ,&l);
|
||
+ } else if ((val & 0xfc00) == 0xf800) { /* 64 <= len < 128 */
|
||
+ len = 0x0040 | ((val >> 4) & 0x003f);
|
||
+ bits -= 4;
|
||
+ getbits(ibuf, 4 , &i ,&l);
|
||
+ } else if ((val & 0xfe00) == 0xfc00) { /* 128 <= len < 256 */
|
||
+ len = 0x0080 | ((val >> 2) & 0x007f);
|
||
+ bits -= 6;
|
||
+ getbits(ibuf, 6 , &i ,&l);
|
||
+ } else if ((val & 0xff00) == 0xfe00) { /* 256 <= len < 512 */
|
||
+ len = 0x0100 | (val & 0x00ff);
|
||
+ bits -= 8;
|
||
+ i++;
|
||
+ } else {
|
||
+ bits -= 8;
|
||
+ val = (val << 8) | getbyte(ibuf, ++i, l);
|
||
+ if ((val & 0xff8000) == 0xff0000) { /* 512 <= len < 1024 */
|
||
+ len = 0x000200 | ((val >> 6) & 0x0001ff);
|
||
+ bits -= 2;
|
||
+ getbits(ibuf, 2 , &i ,&l);
|
||
+ } else if ((val & 0xffc000) == 0xff8000) {/* 1024 <= len < 2048 */
|
||
+ len = 0x000400 | ((val >> 4) & 0x0003ff);
|
||
+ bits -= 4;
|
||
+ getbits(ibuf, 4 , &i ,&l);
|
||
+ } else if ((val & 0xffe000) == 0xffc000) {/* 2048 <= len < 4096 */
|
||
+ len = 0x000800 | ((val >> 2) & 0x0007ff);
|
||
+ bits -= 6;
|
||
+ getbits(ibuf, 6 , &i ,&l);
|
||
+ } else if ((val & 0xfff000) == 0xffe000) {/* 4096 <= len < 8192 */
|
||
+ len = 0x001000 | (val & 0x000fff);
|
||
+ bits -= 8;
|
||
+ i++;
|
||
+ } else { /* this shouldn't happen */
|
||
+ if (state->debug)
|
||
+ printk(KERN_DEBUG "%s%d: wrong length code: 0x%X\n",
|
||
+ __FUNCTION__, state->unit, val);
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ }
|
||
+ }
|
||
+ s = state->hist + state->histptr;
|
||
+ state->histptr += len;
|
||
+ olen += len;
|
||
+ if (state->histptr < 2*MPPE_HIST_LEN) {
|
||
+ /* copy uncompressed bytes to the history */
|
||
+
|
||
+ /* In some cases len may be greater than off. It means that memory
|
||
+ * areas pointed by s and s-off overlap. I had used memmove() here
|
||
+ * because I thought that it acts as libc's version. Unfortunately,
|
||
+ * I was wrong. :-) I got strange errors sometimes. Wilfried suggested
|
||
+ * using of byte by byte copying here and strange errors disappeared.
|
||
+ */
|
||
+ lamecopy(s, s - off, len);
|
||
+ } else {
|
||
+ /* buffer overflow; drop packet */
|
||
+ if (state->debug)
|
||
+ printk(KERN_ERR "%s%d: trying to write outside history "
|
||
+ "buffer\n", __FUNCTION__, state->unit);
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ }
|
||
+
|
||
+ /* Do PFC decompression */
|
||
+ len = olen;
|
||
+ if ((history[0] & 0x01) != 0) {
|
||
+ obuf[0] = 0;
|
||
+ obuf++;
|
||
+ len++;
|
||
+ }
|
||
+
|
||
+ if (len <= osize) {
|
||
+ /* copy uncompressed packet to the output buffer */
|
||
+ memcpy(obuf, history, olen);
|
||
+ } else {
|
||
+ /* buffer overflow; drop packet */
|
||
+ if (state->debug)
|
||
+ printk(KERN_ERR "%s%d: too big uncompressed packet: %d\n",
|
||
+ __FUNCTION__, state->unit, len + (PPP_HDRLEN / 2));
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+
|
||
+ return (int) len;
|
||
+}
|
||
+
|
||
+int
|
||
+mppe_decompress(void *arg, unsigned char *ibuf, int isize,
|
||
+ unsigned char *obuf, int osize)
|
||
+{
|
||
+ struct ppp_mppe_state *state = (struct ppp_mppe_state *)arg;
|
||
+ int seq, bits, uncomplen;
|
||
+
|
||
+ if (isize <= PPP_HDRLEN + MPPE_OVHD) {
|
||
+ if (state->debug) {
|
||
+ printk(KERN_DEBUG "%s%d: short packet (len=%d)\n", __FUNCTION__,
|
||
+ state->unit, isize);
|
||
+ }
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+
|
||
+ /* Get coherency counter and control bits from input buffer */
|
||
+ seq = MPPE_CCOUNT(ibuf);
|
||
+ bits = MPPE_BITS(ibuf);
|
||
+
|
||
+ if (state->stateless) {
|
||
+ /* RFC 3078, sec 8.1. */
|
||
+ mppe_increase_ccount(state);
|
||
+ if ((seq != state->ccount) && state->debug)
|
||
+ printk(KERN_DEBUG "%s%d: bad sequence number: %d, expected: %d\n",
|
||
+ __FUNCTION__, state->unit, seq, state->ccount);
|
||
+ while (seq != state->ccount)
|
||
+ mppe_increase_ccount(state);
|
||
+ } else {
|
||
+ /* RFC 3078, sec 8.2. */
|
||
+ if (state->flushexpected) { /* discard state */
|
||
+ if ((bits & MPPE_BIT_FLUSHED)) { /* we received expected FLUSH bit */
|
||
+ while (seq != state->ccount)
|
||
+ mppe_increase_ccount(state);
|
||
+ state->flushexpected = 0;
|
||
+ } else /* drop packet*/
|
||
+ return DECOMP_ERROR;
|
||
+ } else { /* normal state */
|
||
+ mppe_increase_ccount(state);
|
||
+ if (seq != state->ccount) {
|
||
+ /* Packet loss detected, enter the discard state. */
|
||
+ if (state->debug)
|
||
+ printk(KERN_DEBUG "%s%d: bad sequence number: %d, expected: %d\n",
|
||
+ __FUNCTION__, state->unit, seq, state->ccount);
|
||
+ state->flushexpected = 1;
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ }
|
||
+ if (state->mppe && (bits & MPPE_BIT_FLUSHED)) {
|
||
+ arc4_setkey(state, state->session_key, state->keylen);
|
||
+ }
|
||
+ }
|
||
+
|
||
+ if (state->mppc && (bits & (MPPE_BIT_FLUSHED | MPPE_BIT_RESET))) {
|
||
+ state->histptr = MPPE_HIST_LEN;
|
||
+ if ((bits & MPPE_BIT_FLUSHED)) {
|
||
+ memset(state->hist + MPPE_HIST_LEN, 0, MPPE_HIST_LEN*sizeof(u8));
|
||
+ } else
|
||
+ if ((bits & MPPE_BIT_RESET)) {
|
||
+ memcpy(state->hist, state->hist + MPPE_HIST_LEN, MPPE_HIST_LEN);
|
||
+ }
|
||
+ }
|
||
+
|
||
+ /* Fill in the first part of the PPP header. The protocol field
|
||
+ comes from the decompressed data. */
|
||
+ obuf[0] = PPP_ADDRESS(ibuf);
|
||
+ obuf[1] = PPP_CONTROL(ibuf);
|
||
+ obuf += PPP_HDRLEN / 2;
|
||
+
|
||
+ if (state->mppe) { /* process encrypted packet */
|
||
+ if ((bits & MPPE_BIT_ENCRYPTED)) {
|
||
+ /* OK, packet encrypted, so decrypt it */
|
||
+ if (state->mppc && (bits & MPPE_BIT_COMP)) {
|
||
+ /* Hack warning !!! RC4 implementation which we use does
|
||
+ decryption "in place" - it means that input and output
|
||
+ buffers can be *the same* memory area. Therefore we don't
|
||
+ need to use a temporary buffer. But be careful - other
|
||
+ implementations don't have to be so nice. */
|
||
+ arc4_decrypt(state, ibuf + PPP_HDRLEN + (MPPE_OVHD / 2), isize -
|
||
+ PPP_HDRLEN - (MPPE_OVHD / 2), ibuf + PPP_HDRLEN +
|
||
+ (MPPE_OVHD / 2));
|
||
+ uncomplen = mppc_decompress(state, ibuf + PPP_HDRLEN +
|
||
+ (MPPE_OVHD / 2), obuf, isize -
|
||
+ PPP_HDRLEN - (MPPE_OVHD / 2),
|
||
+ osize - (PPP_HDRLEN / 2));
|
||
+ if (uncomplen == DECOMP_ERROR) {
|
||
+ state->flushexpected = 1;
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ uncomplen += PPP_HDRLEN / 2;
|
||
+ (state->stats).comp_bytes += isize;
|
||
+ (state->stats).comp_packets++;
|
||
+ } else {
|
||
+ uncomplen = isize - MPPE_OVHD;
|
||
+ /* Decrypt the first byte in order to check if it is
|
||
+ compressed or uncompressed protocol field */
|
||
+ arc4_decrypt(state, ibuf + PPP_HDRLEN + (MPPE_OVHD / 2), 1, obuf);
|
||
+ /* Do PFC decompression */
|
||
+ if ((obuf[0] & 0x01) != 0) {
|
||
+ obuf[1] = obuf[0];
|
||
+ obuf[0] = 0;
|
||
+ obuf++;
|
||
+ uncomplen++;
|
||
+ }
|
||
+ /* And finally, decrypt the rest of the frame. */
|
||
+ arc4_decrypt(state, ibuf + PPP_HDRLEN + (MPPE_OVHD / 2) + 1,
|
||
+ isize - PPP_HDRLEN - (MPPE_OVHD / 2) - 1, obuf + 1);
|
||
+ (state->stats).inc_bytes += isize;
|
||
+ (state->stats).inc_packets++;
|
||
+ }
|
||
+ } else { /* this shouldn't happen */
|
||
+ if (state->debug)
|
||
+ printk(KERN_ERR "%s%d: encryption negotiated but not an "
|
||
+ "encrypted packet received\n", __FUNCTION__, state->unit);
|
||
+ mppe_change_key(state, 0);
|
||
+ state->flushexpected = 1;
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ } else {
|
||
+ if (state->mppc) { /* no MPPE, only MPPC */
|
||
+ if ((bits & MPPE_BIT_COMP)) {
|
||
+ uncomplen = mppc_decompress(state, ibuf + PPP_HDRLEN +
|
||
+ (MPPE_OVHD / 2), obuf, isize -
|
||
+ PPP_HDRLEN - (MPPE_OVHD / 2),
|
||
+ osize - (PPP_HDRLEN / 2));
|
||
+ if (uncomplen == DECOMP_ERROR) {
|
||
+ state->flushexpected = 1;
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ uncomplen += PPP_HDRLEN / 2;
|
||
+ (state->stats).comp_bytes += isize;
|
||
+ (state->stats).comp_packets++;
|
||
+ } else {
|
||
+ memcpy(obuf, ibuf + PPP_HDRLEN + (MPPE_OVHD / 2), isize -
|
||
+ PPP_HDRLEN - (MPPE_OVHD / 2));
|
||
+ uncomplen = isize - MPPE_OVHD;
|
||
+ (state->stats).inc_bytes += isize;
|
||
+ (state->stats).inc_packets++;
|
||
+ }
|
||
+ } else { /* this shouldn't happen */
|
||
+ if (state->debug)
|
||
+ printk(KERN_ERR "%s%d: error - not an MPPC or MPPE frame "
|
||
+ "received\n", __FUNCTION__, state->unit);
|
||
+ state->flushexpected = 1;
|
||
+ return DECOMP_ERROR;
|
||
+ }
|
||
+ }
|
||
+
|
||
+ (state->stats).unc_bytes += uncomplen;
|
||
+ (state->stats).unc_packets++;
|
||
+
|
||
+ return uncomplen;
|
||
+}
|
||
+
|
||
+
|
||
+/************************************************************
|
||
+ * Module interface table
|
||
+ ************************************************************/
|
||
+
|
||
+/* These are in ppp_generic.c */
|
||
+extern int ppp_register_compressor (struct compressor *cp);
|
||
+extern void ppp_unregister_compressor (struct compressor *cp);
|
||
+
|
||
+/*
|
||
+ * Functions exported to ppp_generic.c.
|
||
+ *
|
||
+ * In case of MPPC/MPPE there is no need to process incompressible data
|
||
+ * because such a data is sent in MPPC/MPPE frame. Therefore the (*incomp)
|
||
+ * callback function isn't needed.
|
||
+ */
|
||
+struct compressor ppp_mppe = {
|
||
+ CI_MPPE, /* compress_proto */
|
||
+ mppe_comp_alloc, /* comp_alloc */
|
||
+ mppe_comp_free, /* comp_free */
|
||
+ mppe_comp_init, /* comp_init */
|
||
+ mppe_comp_reset, /* comp_reset */
|
||
+ mppe_compress, /* compress */
|
||
+ mppe_stats, /* comp_stat */
|
||
+ mppe_decomp_alloc, /* decomp_alloc */
|
||
+ mppe_comp_free, /* decomp_free */
|
||
+ mppe_decomp_init, /* decomp_init */
|
||
+ mppe_decomp_reset, /* decomp_reset */
|
||
+ mppe_decompress, /* decompress */
|
||
+ NULL, /* incomp */
|
||
+ mppe_stats, /* decomp_stat */
|
||
+};
|
||
+
|
||
+/************************************************************
|
||
+ * Module support routines
|
||
+ ************************************************************/
|
||
+
|
||
+int __init mppe_module_init(void)
|
||
+{
|
||
+ int answer;
|
||
+
|
||
+ /* When the module is compiled into kernel, it is initialized before
|
||
+ * CryptoAPI. Therefore the code below reports that there is no crypto
|
||
+ * stuff in the kernel. Marlon de Boer who has pointed out the problem,
|
||
+ * has sent also a message to CryptoAPI developers, so maybe in the future
|
||
+ * the code will be uncommented.
|
||
+ *
|
||
+ if (!(crypto_alg_available("arc4", 0) && crypto_alg_available("sha1", 0))) {
|
||
+ printk(KERN_ERR "Kernel doesn't provide ARC4 and/or SHA1 algorithms "
|
||
+ "required by MPPE/MPPC. Check CryptoAPI configuration.\n");
|
||
+ return -ENODEV;
|
||
+ }
|
||
+ */
|
||
+
|
||
+ /* Allocate space for SHAPad1, SHAPad2 and ... */
|
||
+ sha_pad = kmalloc(sizeof(struct sha_pad), GFP_KERNEL);
|
||
+ if (sha_pad == NULL)
|
||
+ return -ENOMEM;
|
||
+ /* ... initialize them */
|
||
+ memset(sha_pad->sha_pad1, 0x00, sizeof(sha_pad->sha_pad1));
|
||
+ memset(sha_pad->sha_pad2, 0xf2, sizeof(sha_pad->sha_pad2));
|
||
+
|
||
+ answer = ppp_register_compressor(&ppp_mppe);
|
||
+ if (answer == 0) {
|
||
+ printk(KERN_INFO "MPPE/MPPC encryption/compression module registered\n");
|
||
+ }
|
||
+ return answer;
|
||
+}
|
||
+
|
||
+void __exit mppe_module_cleanup(void)
|
||
+{
|
||
+ kfree(sha_pad);
|
||
+ ppp_unregister_compressor(&ppp_mppe);
|
||
+ printk(KERN_INFO "MPPE/MPPC encryption/compression module unregistered\n");
|
||
+}
|
||
+
|
||
+module_init(mppe_module_init);
|
||
+module_exit(mppe_module_cleanup);
|
||
+
|
||
+MODULE_AUTHOR("Jan Dubiec <jdx@slackware.pl>");
|
||
+MODULE_DESCRIPTION("MPPE/MPPC encryption/compression module for Linux");
|
||
+MODULE_LICENSE("Dual BSD/GPL");
|
||
diff -ruN linux-2.4.29.orig/include/linux/ppp-comp.h linux-2.4.29/include/linux/ppp-comp.h
|
||
--- linux-2.4.29.orig/include/linux/ppp-comp.h 2005-02-02 22:18:25.000000000 +0100
|
||
+++ linux-2.4.29/include/linux/ppp-comp.h 2005-02-02 22:41:01.000000000 +0100
|
||
@@ -28,7 +28,7 @@
|
||
*/
|
||
|
||
/*
|
||
- * ==FILEVERSION 980319==
|
||
+ * ==FILEVERSION 20040509==
|
||
*
|
||
* NOTE TO MAINTAINERS:
|
||
* If you modify this file at all, please set the above date.
|
||
@@ -78,7 +78,7 @@
|
||
|
||
/* 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 +187,42 @@
|
||
#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.
|
||
*/
|
||
|