blob: 77bba28a277cb6e1998a05396e7f5a5051308932 [file] [log] [blame]
/*
* Copyright (c) 1999, 2000, 2001 Markus Friedl. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include "includes.h"
RCSID("$OpenBSD: compat.c,v 1.51 2001/06/25 08:25:37 markus Exp $");
#ifdef HAVE_LIBPCRE
# include <pcreposix.h>
#else /* Use native regex libraries */
# ifdef HAVE_REGEX_H
# include <regex.h>
# else
# include "openbsd-compat/fake-regex.h"
# endif
#endif /* HAVE_LIBPCRE */
#include "packet.h"
#include "xmalloc.h"
#include "compat.h"
#include "log.h"
int compat13 = 0;
int compat20 = 0;
int datafellows = 0;
void
enable_compat20(void)
{
verbose("Enabling compatibility mode for protocol 2.0");
compat20 = 1;
}
void
enable_compat13(void)
{
verbose("Enabling compatibility mode for protocol 1.3");
compat13 = 1;
}
/* datafellows bug compatibility */
void
compat_datafellows(const char *version)
{
int i, ret;
char ebuf[1024];
regex_t reg;
static struct {
char *pat;
int bugs;
} check[] = {
{ "^OpenSSH[-_]2\\.[012]",
SSH_OLD_SESSIONID|SSH_BUG_BANNER|
SSH_OLD_DHGEX|SSH_BUG_NOREKEY },
{ "^OpenSSH_2\\.3\\.0", SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES|
SSH_OLD_DHGEX|SSH_BUG_NOREKEY},
{ "^OpenSSH_2\\.3\\.", SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
SSH_BUG_NOREKEY},
{ "^OpenSSH_2\\.5\\.[01]p1",
SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
SSH_BUG_NOREKEY },
{ "^OpenSSH_2\\.5\\.[012]",
SSH_OLD_DHGEX|SSH_BUG_NOREKEY },
{ "^OpenSSH_2\\.5\\.3",
SSH_BUG_NOREKEY },
{ "^OpenSSH", 0 },
{ "MindTerm", 0 },
{ "^2\\.1\\.0", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE },
{ "^2\\.1 ", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE },
{ "^2\\.0\\.1[3-9]", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
SSH_BUG_PKOK|SSH_BUG_RSASIGMD5|
SSH_BUG_HBSERVICE|SSH_BUG_OPENFAILURE },
{ "^2\\.0\\.1[1-2]", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
SSH_BUG_PKAUTH|SSH_BUG_PKOK|
SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE },
{ "^2\\.0\\.", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
SSH_BUG_PKAUTH|SSH_BUG_PKOK|
SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE|
SSH_BUG_DERIVEKEY },
{ "^2\\.[23]\\.0", SSH_BUG_HMAC|SSH_BUG_RSASIGMD5 },
{ "^2\\.3\\.", SSH_BUG_RSASIGMD5 },
{ "^2\\.[2-9]\\.", 0 },
{ "^2\\.4$", SSH_OLD_SESSIONID }, /* Van Dyke */
{ "^3\\.0 SecureCRT", SSH_OLD_SESSIONID },
{ "^1\\.7 SecureFX", SSH_OLD_SESSIONID },
{ "^1\\.2\\.1[89]", SSH_BUG_IGNOREMSG },
{ "^1\\.2\\.2[012]", SSH_BUG_IGNOREMSG },
{ "^1\\.3\\.2", SSH_BUG_IGNOREMSG }, /* f-secure */
{ "^SSH Compatible Server", /* Netscreen */
SSH_BUG_PASSWORDPAD },
{ "^OSU_0", SSH_BUG_PASSWORDPAD },
{ "^OSU_1\\.[0-4]", SSH_BUG_PASSWORDPAD },
{ "^OSU_1\\.5alpha[1-3]",
SSH_BUG_PASSWORDPAD },
{ "^SSH_Version_Mapper",
SSH_BUG_SCANNER },
{ NULL, 0 }
};
/* process table, return first match */
for (i = 0; check[i].pat; i++) {
ret = regcomp(&reg, check[i].pat, REG_EXTENDED|REG_NOSUB);
if (ret != 0) {
regerror(ret, &reg, ebuf, sizeof(ebuf));
ebuf[sizeof(ebuf)-1] = '\0';
error("regerror: %s", ebuf);
continue;
}
ret = regexec(&reg, version, 0, NULL, 0);
regfree(&reg);
if (ret == 0) {
debug("match: %s pat %s", version, check[i].pat);
datafellows = check[i].bugs;
return;
}
}
debug("no match: %s", version);
}
#define SEP ","
int
proto_spec(const char *spec)
{
char *s, *p, *q;
int ret = SSH_PROTO_UNKNOWN;
if (spec == NULL)
return ret;
q = s = xstrdup(spec);
for ((p = strsep(&q, SEP)); p && *p != '\0'; (p = strsep(&q, SEP))) {
switch(atoi(p)) {
case 1:
if (ret == SSH_PROTO_UNKNOWN)
ret |= SSH_PROTO_1_PREFERRED;
ret |= SSH_PROTO_1;
break;
case 2:
ret |= SSH_PROTO_2;
break;
default:
log("ignoring bad proto spec: '%s'.", p);
break;
}
}
xfree(s);
return ret;
}
char *
compat_cipher_proposal(char *cipher_prop)
{
char *orig_prop, *fix_ciphers;
char *cp, *tmp;
size_t len;
if (!(datafellows & SSH_BUG_BIGENDIANAES))
return(cipher_prop);
len = strlen(cipher_prop) + 1;
fix_ciphers = xmalloc(len);
*fix_ciphers = '\0';
tmp = orig_prop = xstrdup(cipher_prop);
while((cp = strsep(&tmp, ",")) != NULL) {
if (strncmp(cp, "aes", 3) && strncmp(cp, "rijndael", 8)) {
if (*fix_ciphers)
strlcat(fix_ciphers, ",", len);
strlcat(fix_ciphers, cp, len);
}
}
xfree(orig_prop);
debug2("Original cipher proposal: %s", cipher_prop);
debug2("Compat cipher proposal: %s", fix_ciphers);
if (!*fix_ciphers)
fatal("No available ciphers found.");
return(fix_ciphers);
}