* 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, 55 insertions, 14 deletions

diff --git a/buffer.c b/buffer.c
index 487e08105..e02e1e35c 100644
--- a/buffer.c
+++ b/buffer.c
@@ -1,3 +1,4 @@
+/* $OpenBSD: buffer.c,v 1.31 2006/08/03 03:34:41 deraadt Exp $ */
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
  * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
@@ -12,12 +13,21 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: buffer.c,v 1.23 2005/03/14 11:46:56 markus Exp $");
+
+#include <sys/param.h>
+
+#include <stdio.h>
+#include <string.h>
+#include <stdarg.h>
 
 #include "xmalloc.h"
 #include "buffer.h"
 #include "log.h"
 
+#define BUFFER_MAX_CHUNK        0x100000
+#define BUFFER_MAX_LEN          0xa00000
+#define BUFFER_ALLOCSZ          0x008000
+
 /* Initializes the buffer structure. */
 
 void
@@ -66,6 +76,23 @@ buffer_append(Buffer *buffer, const void *data, u_int len)
         memcpy(p, data, len);
 }
 
+static int
+buffer_compact(Buffer *buffer)
+{
+        /*
+         * If the buffer is quite empty, but all data is at the end, move the
+         * data to the beginning.
+         */
+        if (buffer->offset > MIN(buffer->alloc, BUFFER_MAX_CHUNK)) {
+                memmove(buffer->buf, buffer->buf + buffer->offset,
+                        buffer->end - buffer->offset);
+                buffer->end -= buffer->offset;
+                buffer->offset = 0;
+                return (1);
+        }
+        return (0);
+}
+
 /*
  * Appends space to the buffer, expanding the buffer if necessary. This does
  * not actually copy the data into the buffer, but instead returns a pointer
@@ -93,29 +120,43 @@ restart:
                 buffer->end += len;
                 return p;
         }
-        /*
-         * If the buffer is quite empty, but all data is at the end, move the
-         * data to the beginning and retry.
-         */
-        if (buffer->offset > MIN(buffer->alloc, BUFFER_MAX_CHUNK)) {
-                memmove(buffer->buf, buffer->buf + buffer->offset,
-                        buffer->end - buffer->offset);
-                buffer->end -= buffer->offset;
-                buffer->offset = 0;
+
+        /* Compact data back to the start of the buffer if necessary */
+        if (buffer_compact(buffer))
                 goto restart;
-        }
-        /* Increase the size of the buffer and retry. */
 
-        newlen = buffer->alloc + len + 32768;
+        /* Increase the size of the buffer and retry. */
+        newlen = roundup(buffer->alloc + len, BUFFER_ALLOCSZ);
         if (newlen > BUFFER_MAX_LEN)
                 fatal("buffer_append_space: alloc %u not supported",
                     newlen);
-        buffer->buf = xrealloc(buffer->buf, newlen);
+        buffer->buf = xrealloc(buffer->buf, 1, newlen);
         buffer->alloc = newlen;
         goto restart;
         /* NOTREACHED */
 }
 
+/*
+ * Check whether an allocation of 'len' will fit in the buffer
+ * This must follow the same math as buffer_append_space
+ */
+int
+buffer_check_alloc(Buffer *buffer, u_int len)
+{
+        if (buffer->offset == buffer->end) {
+                buffer->offset = 0;
+                buffer->end = 0;
+        }
+ restart:
+        if (buffer->end + len < buffer->alloc)
+                return (1);
+        if (buffer_compact(buffer))
+                goto restart;
+        if (roundup(buffer->alloc + len, BUFFER_ALLOCSZ) <= BUFFER_MAX_LEN)
+                return (1);
+        return (0);
+}
+
 /* Returns the number of bytes of data in the buffer. */
 
 u_int