* New upstream release (closes: #395507, #397961, #420035). Important

  changes not previously backported to 4.3p2:
  - 4.4/4.4p1 (http://www.openssh.org/txt/release-4.4):
    + On portable OpenSSH, fix a GSSAPI authentication abort that could be
      used to determine the validity of usernames on some platforms.
    + Implemented conditional configuration in sshd_config(5) using the
      "Match" directive. This allows some configuration options to be
      selectively overridden if specific criteria (based on user, group,
      hostname and/or address) are met. So far a useful subset of
      post-authentication options are supported and more are expected to
      be added in future releases.
    + Add support for Diffie-Hellman group exchange key agreement with a
      final hash of SHA256.
    + Added a "ForceCommand" directive to sshd_config(5). Similar to the
      command="..." option accepted in ~/.ssh/authorized_keys, this forces
      the execution of the specified command regardless of what the user
      requested. This is very useful in conjunction with the new "Match"
      option.
    + Add a "PermitOpen" directive to sshd_config(5). This mirrors the
      permitopen="..." authorized_keys option, allowing fine-grained
      control over the port-forwardings that a user is allowed to
      establish.
    + Add optional logging of transactions to sftp-server(8).
    + ssh(1) will now record port numbers for hosts stored in
      ~/.ssh/known_hosts when a non-standard port has been requested
      (closes: #50612).
    + Add an "ExitOnForwardFailure" option to cause ssh(1) to exit (with a
      non-zero exit code) when requested port forwardings could not be
      established.
    + Extend sshd_config(5) "SubSystem" declarations to allow the
      specification of command-line arguments.
    + Replacement of all integer overflow susceptible invocations of
      malloc(3) and realloc(3) with overflow-checking equivalents.
    + Many manpage fixes and improvements.
    + Add optional support for OpenSSL hardware accelerators (engines),
      enabled using the --with-ssl-engine configure option.
    + Tokens in configuration files may be double-quoted in order to
      contain spaces (closes: #319639).
    + Move a debug() call out of a SIGCHLD handler, fixing a hang when the
      session exits very quickly (closes: #307890).
    + Fix some incorrect buffer allocation calculations (closes: #410599).
    + ssh-add doesn't ask for a passphrase if key file permissions are too
      liberal (closes: #103677).
    + Likewise, ssh doesn't ask either (closes: #99675).
  - 4.6/4.6p1 (http://www.openssh.org/txt/release-4.6):
    + sshd now allows the enabling and disabling of authentication methods
      on a per user, group, host and network basis via the Match directive
      in sshd_config.
    + Fixed an inconsistent check for a terminal when displaying scp
      progress meter (closes: #257524).
    + Fix "hang on exit" when background processes are running at the time
      of exit on a ttyful/login session (closes: #88337).
* Update to current GSSAPI patch from
  http://www.sxw.org.uk/computing/patches/openssh-4.6p1-gsskex-20070312.patch;
  install ChangeLog.gssapi.

1 files changed, 45 insertions, 29 deletions

diff --git a/kexgssc.c b/kexgssc.c
index 9830ad384..7c4a56f45 100644
--- a/kexgssc.c
+++ b/kexgssc.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001-2005 Simon Wilkinson. All rights reserved.
+ * Copyright (c) 2001-2006 Simon Wilkinson. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
@@ -26,24 +26,29 @@
 
 #ifdef GSSAPI
 
+#include "includes.h"
+
 #include <openssl/crypto.h>
 #include <openssl/bn.h>
 
+#include <string.h>
+
 #include "xmalloc.h"
 #include "buffer.h"
-#include "bufaux.h"
+#include "ssh2.h"
+#include "key.h"
+#include "cipher.h"
 #include "kex.h"
 #include "log.h"
 #include "packet.h"
 #include "dh.h"
-#include "canohost.h"
-#include "ssh2.h"
+
 #include "ssh-gss.h"
 
 void
 kexgss_client(Kex *kex) {
         gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
-        gss_buffer_desc recv_tok, gssbuf, msg_tok, *token_ptr;
+        gss_buffer_desc recv_tok, gssbuf, msg_tok, *token_ptr;
         Gssctxt *ctxt;
         OM_uint32 maj_status, min_status, ret_flags;
         u_int klen, kout, slen = 0, hashlen, strlen;
@@ -58,22 +63,27 @@ kexgss_client(Kex *kex) {
         char *lang;
         int type = 0;
         int first = 1;
-        int gex = 0;
-        int nbits, min, max;
+        int nbits = 0, min = DH_GRP_MIN, max = DH_GRP_MAX;
 
         /* Initialise our GSSAPI world */       
         ssh_gssapi_build_ctx(&ctxt);
-        if (ssh_gssapi_id_kex(ctxt, kex->name, &gex) == NULL)
+        if (ssh_gssapi_id_kex(ctxt, kex->name, kex->kex_type) 
+            == GSS_C_NO_OID)
                 fatal("Couldn't identify host exchange");
 
         if (ssh_gssapi_import_name(ctxt, kex->gss_host))
                 fatal("Couldn't import hostname");
         
-        if (gex) {
+        switch (kex->kex_type) {
+        case KEX_GSS_GRP1_SHA1:
+                dh = dh_new_group1();
+                break;
+        case KEX_GSS_GRP14_SHA1:
+                dh = dh_new_group14();
+                break;
+        case KEX_GSS_GEX_SHA1:
                 debug("Doing group exchange\n");
                 nbits = dh_estimate(kex->we_need * 8);
-                min = DH_GRP_MIN;
-                max = DH_GRP_MAX;
                 packet_start(SSH2_MSG_KEXGSS_GROUPREQ);
                 packet_put_int(min);
                 packet_put_int(nbits);
@@ -96,8 +106,9 @@ kexgss_client(Kex *kex) {
                             min, BN_num_bits(p), max);
 
                 dh = dh_new_group(g, p);
-        } else {
-                dh = dh_new_group1();
+                break;
+        default:
+                fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
         }
         
         /* Step 1 - e is dh->pub_key */
@@ -205,7 +216,7 @@ kexgss_client(Kex *kex) {
                                 min_status = packet_get_int();
                                 msg = packet_get_string(NULL);
                                 lang = packet_get_string(NULL);
-                                fatal("GSSAPI Error: \n%s",msg);
+                                fatal("GSSAPI Error: \n%.400s",msg);
                         default:
                                 packet_disconnect("Protocol error: didn't expect packet type %d",
                                 type);
@@ -240,7 +251,21 @@ kexgss_client(Kex *kex) {
         memset(kbuf, 0, klen);
         xfree(kbuf);
 
-        if (gex) {
+        switch (kex->kex_type) {
+        case KEX_GSS_GRP1_SHA1:
+        case KEX_GSS_GRP14_SHA1:
+                kex_dh_hash( kex->client_version_string, 
+                    kex->server_version_string,
+                    buffer_ptr(&kex->my), buffer_len(&kex->my),
+                    buffer_ptr(&kex->peer), buffer_len(&kex->peer),
+                    serverhostkey, slen, /* server host key */
+                    dh->pub_key,        /* e */
+                    dh_server_pub,      /* f */
+                    shared_secret,      /* K */
+                    &hash, &hashlen
+                );
+                break;
+        case KEX_GSS_GEX_SHA1:
                 kexgex_hash(
                     kex->evp_md,
                     kex->client_version_string,
@@ -255,24 +280,15 @@ kexgss_client(Kex *kex) {
                     shared_secret,
                     &hash, &hashlen
                 );
-        } else {
-                /* The GSS hash is identical to the DH one */
-                kex_dh_hash( kex->client_version_string, 
-                    kex->server_version_string,
-                    buffer_ptr(&kex->my), buffer_len(&kex->my),
-                    buffer_ptr(&kex->peer), buffer_len(&kex->peer),
-                    serverhostkey, slen, /* server host key */
-                    dh->pub_key,        /* e */
-                    dh_server_pub,      /* f */
-                    shared_secret,      /* K */
-                    &hash, &hashlen
-                );
-        }
+                break;
+        default:
+                fatal("%s: Unexpected KEX type %d", __func__, kex->kex_type);
+        }
 
         gssbuf.value = hash;
         gssbuf.length = hashlen;
 
-        /* Verify that the hash matches the MIC we just got. */
+        /* Verify that the hash matches the MIC we just got. */
         if (GSS_ERROR(ssh_gssapi_checkmic(ctxt, &gssbuf, &msg_tok)))
                 packet_disconnect("Hash's MIC didn't verify");