- CVE-2006-4924 from gentoo

Changed files:
    openssh-identical-simple-dos-2.patch -> 1.1

diff --git a/openssh-identical-simple-dos-2.patch b/openssh-identical-simple-dos-2.patch
new file mode 100644 (file)
index 0000000..22c8bea
--- /dev/null
+++ b/openssh-identical-simple-dos-2.patch
@@ -0,0 +1,119 @@
+http://bugs.gentoo.org/148228
+
+taken from upstream cvs and munged a little to apply against 4.3p2
+
+===================================================================
+RCS file: /usr/OpenBSD/cvs/src/usr.bin/ssh/deattack.c,v
+retrieving revision 1.29
+retrieving revision 1.30
+diff -u -r1.29 -r1.30
+--- src/usr.bin/ssh/deattack.c 2006/08/03 03:34:42     1.29
++++ src/usr.bin/ssh/deattack.c 2006/09/16 19:53:37     1.30
+@@ -30,6 +30,24 @@
+ #include "crc32.h"
+ #include "misc.h"
+ 
++/*
++ * CRC attack detection has a worst-case behaviour that is O(N^3) over
++ * the number of identical blocks in a packet. This behaviour can be 
++ * exploited to create a limited denial of service attack. 
++ * 
++ * However, because we are dealing with encrypted data, identical
++ * blocks should only occur every 2^35 maximally-sized packets or so. 
++ * Consequently, we can detect this DoS by looking for identical blocks
++ * in a packet.
++ *
++ * The parameter below determines how many identical blocks we will
++ * accept in a single packet, trading off between attack detection and
++ * likelihood of terminating a legitimate connection. A value of 32 
++ * corresponds to an average of 2^40 messages before an attack is
++ * misdetected
++ */
++#define MAX_IDENTICAL 32
++
+ /* SSH Constants */
+ #define SSH_MAXBLOCKS (32 * 1024)
+ #define SSH_BLOCKSIZE (8)
+@@ -85,7 +103,7 @@
+       static u_int16_t *h = (u_int16_t *) NULL;
+       static u_int32_t n = HASH_MINSIZE / HASH_ENTRYSIZE;
+       u_int32_t i, j;
+-      u_int32_t l;
++      u_int32_t l, same;
+       u_char *c;
+       u_char *d;
+ 
+@@ -122,11 +140,13 @@
+       if (IV)
+               h[HASH(IV) & (n - 1)] = HASH_IV;
+ 
+-      for (c = buf, j = 0; c < (buf + len); c += SSH_BLOCKSIZE, j++) {
++      for (c = buf, same = j = 0; c < (buf + len); c += SSH_BLOCKSIZE, j++) {
+               for (i = HASH(c) & (n - 1); h[i] != HASH_UNUSED;
+                   i = (i + 1) & (n - 1)) {
++            if (!CMP(c, buf + h[i] * SSH_BLOCKSIZE) && ++same > MAX_IDENTICAL)
++                return (DEATTACK_DOS_DETECTED);
+                       if (h[i] == HASH_IV) {
+                               if (!CMP(c, IV)) {
+                                       if (check_crc(c, buf, len, IV))
+                                               return (DEATTACK_DETECTED);
+                                       else
+===================================================================
+RCS file: /usr/OpenBSD/cvs/src/usr.bin/ssh/packet.c,v
+retrieving revision 1.143
+retrieving revision 1.144
+diff -u -r1.143 -r1.144
+--- src/usr.bin/ssh/packet.c   2006/08/05 08:34:04     1.143
++++ src/usr.bin/ssh/packet.c   2006/09/16 19:53:37     1.144
+@@ -991,9 +991,16 @@
+        * (C)1998 CORE-SDI, Buenos Aires Argentina
+        * Ariel Futoransky(futo@core-sdi.com)
+        */
+-      if (!receive_context.plaintext &&
+-          detect_attack(buffer_ptr(&input), padded_len, NULL) == DEATTACK_DETECTED)
+-              packet_disconnect("crc32 compensation attack: network attack detected");
++      if (!receive_context.plaintext) {
++              switch (detect_attack(buffer_ptr(&input), padded_len, NULL)) {
++              case DEATTACK_DETECTED:
++                      packet_disconnect("crc32 compensation attack: "
++                          "network attack detected");
++              case DEATTACK_DOS_DETECTED:
++                      packet_disconnect("deattack denial of "
++                          "service detected");
++              }
++      }
+ 
+       /* Decrypt data to incoming_packet. */
+       buffer_clear(&incoming_packet);
+===================================================================
+RCS file: /usr/OpenBSD/cvs/src/usr.bin/ssh/deattack.h,v
+retrieving revision 1.9
+retrieving revision 1.10
+diff -u -r1.9 -r1.10
+--- src/usr.bin/ssh/deattack.h 2006/03/25 22:22:43     1.9
++++ src/usr.bin/ssh/deattack.h 2006/09/16 19:53:37     1.10
+@@ -25,6 +25,7 @@
+ /* Return codes */
+ #define DEATTACK_OK           0
+ #define DEATTACK_DETECTED     1
++#define DEATTACK_DOS_DETECTED 2
+ 
+ int    detect_attack(u_char *, u_int32_t);
+ #endif
+===================================================================
+RCS file: /usr/OpenBSD/cvs/src/usr.bin/ssh/packet.c,v
+retrieving revision 1.144
+retrieving revision 1.145
+diff -u -r1.144 -r1.145
+--- src/usr.bin/ssh/packet.c   2006/09/16 19:53:37     1.144
++++ src/usr.bin/ssh/packet.c   2006/09/19 21:14:08     1.145
+@@ -682,6 +682,9 @@
+        */
+       after_authentication = 1;
+       for (mode = 0; mode < MODE_MAX; mode++) {
++              /* protocol error: USERAUTH_SUCCESS received before NEWKEYS */
++              if (newkeys[mode] == NULL)
++                      continue;
+               comp = &newkeys[mode]->comp;
+               if (comp && !comp->enabled && comp->type == COMP_DELAYED) {
+                       packet_init_compression();