mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-29 12:03:03 +00:00
294 lines
8.3 KiB
C
294 lines
8.3 KiB
C
/* $OpenBSD: compat.c,v 1.82 2013/12/30 23:52:27 djm Exp $ */
|
|
/*
|
|
* Copyright (c) 1999, 2000, 2001, 2002 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("$FreeBSD$");
|
|
|
|
#include <sys/types.h>
|
|
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <stdarg.h>
|
|
|
|
#include "xmalloc.h"
|
|
#include "buffer.h"
|
|
#include "packet.h"
|
|
#include "compat.h"
|
|
#include "log.h"
|
|
#include "match.h"
|
|
|
|
int compat13 = 0;
|
|
int compat20 = 0;
|
|
int datafellows = 0;
|
|
|
|
void
|
|
enable_compat20(void)
|
|
{
|
|
if (compat20)
|
|
return;
|
|
debug("Enabling compatibility mode for protocol 2.0");
|
|
compat20 = 1;
|
|
}
|
|
void
|
|
enable_compat13(void)
|
|
{
|
|
debug("Enabling compatibility mode for protocol 1.3");
|
|
compat13 = 1;
|
|
}
|
|
/* datafellows bug compatibility */
|
|
void
|
|
compat_datafellows(const char *version)
|
|
{
|
|
int i;
|
|
static struct {
|
|
char *pat;
|
|
int bugs;
|
|
} check[] = {
|
|
{ "OpenSSH-2.0*,"
|
|
"OpenSSH-2.1*,"
|
|
"OpenSSH_2.1*,"
|
|
"OpenSSH_2.2*", SSH_OLD_SESSIONID|SSH_BUG_BANNER|
|
|
SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
|
|
SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
|
|
{ "OpenSSH_2.3.0*", SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES|
|
|
SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
|
|
SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
|
|
{ "OpenSSH_2.3.*", SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
|
|
SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
|
|
SSH_OLD_FORWARD_ADDR},
|
|
{ "OpenSSH_2.5.0p1*,"
|
|
"OpenSSH_2.5.1p1*",
|
|
SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
|
|
SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
|
|
SSH_OLD_FORWARD_ADDR},
|
|
{ "OpenSSH_2.5.0*,"
|
|
"OpenSSH_2.5.1*,"
|
|
"OpenSSH_2.5.2*", SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
|
|
SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
|
|
{ "OpenSSH_2.5.3*", SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
|
|
SSH_OLD_FORWARD_ADDR},
|
|
{ "OpenSSH_2.*,"
|
|
"OpenSSH_3.0*,"
|
|
"OpenSSH_3.1*", SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
|
|
{ "OpenSSH_3.*", SSH_OLD_FORWARD_ADDR },
|
|
{ "Sun_SSH_1.0*", SSH_BUG_NOREKEY|SSH_BUG_EXTEOF},
|
|
{ "OpenSSH_4*", 0 },
|
|
{ "OpenSSH_5*", SSH_NEW_OPENSSH|SSH_BUG_DYNAMIC_RPORT},
|
|
{ "OpenSSH_6.6.1*", SSH_NEW_OPENSSH},
|
|
{ "OpenSSH_6.5*,"
|
|
"OpenSSH_6.6*", SSH_NEW_OPENSSH|SSH_BUG_CURVE25519PAD},
|
|
{ "OpenSSH*", SSH_NEW_OPENSSH },
|
|
{ "*MindTerm*", 0 },
|
|
{ "2.1.0*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
|
|
SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
|
|
SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE|
|
|
SSH_BUG_FIRSTKEX },
|
|
{ "2.1 *", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
|
|
SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
|
|
SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE|
|
|
SSH_BUG_FIRSTKEX },
|
|
{ "2.0.13*,"
|
|
"2.0.14*,"
|
|
"2.0.15*,"
|
|
"2.0.16*,"
|
|
"2.0.17*,"
|
|
"2.0.18*,"
|
|
"2.0.19*", 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|
|
|
SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX },
|
|
{ "2.0.11*,"
|
|
"2.0.12*", 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_DUMMYCHAN|SSH_BUG_FIRSTKEX },
|
|
{ "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|SSH_BUG_DUMMYCHAN|
|
|
SSH_BUG_FIRSTKEX },
|
|
{ "2.2.0*,"
|
|
"2.3.0*", SSH_BUG_HMAC|SSH_BUG_DEBUG|
|
|
SSH_BUG_RSASIGMD5|SSH_BUG_FIRSTKEX },
|
|
{ "2.3.*", SSH_BUG_DEBUG|SSH_BUG_RSASIGMD5|
|
|
SSH_BUG_FIRSTKEX },
|
|
{ "2.4", SSH_OLD_SESSIONID }, /* Van Dyke */
|
|
{ "2.*", SSH_BUG_DEBUG|SSH_BUG_FIRSTKEX|
|
|
SSH_BUG_RFWD_ADDR },
|
|
{ "3.0.*", SSH_BUG_DEBUG },
|
|
{ "3.0 SecureCRT*", SSH_OLD_SESSIONID },
|
|
{ "1.7 SecureFX*", SSH_OLD_SESSIONID },
|
|
{ "1.2.18*,"
|
|
"1.2.19*,"
|
|
"1.2.20*,"
|
|
"1.2.21*,"
|
|
"1.2.22*", SSH_BUG_IGNOREMSG },
|
|
{ "1.3.2*", /* F-Secure */
|
|
SSH_BUG_IGNOREMSG },
|
|
{ "*SSH Compatible Server*", /* Netscreen */
|
|
SSH_BUG_PASSWORDPAD },
|
|
{ "*OSU_0*,"
|
|
"OSU_1.0*,"
|
|
"OSU_1.1*,"
|
|
"OSU_1.2*,"
|
|
"OSU_1.3*,"
|
|
"OSU_1.4*,"
|
|
"OSU_1.5alpha1*,"
|
|
"OSU_1.5alpha2*,"
|
|
"OSU_1.5alpha3*", SSH_BUG_PASSWORDPAD },
|
|
{ "*SSH_Version_Mapper*",
|
|
SSH_BUG_SCANNER },
|
|
{ "Probe-*",
|
|
SSH_BUG_PROBE },
|
|
{ NULL, 0 }
|
|
};
|
|
|
|
/* process table, return first match */
|
|
for (i = 0; check[i].pat; i++) {
|
|
if (match_pattern_list(version, check[i].pat,
|
|
strlen(check[i].pat), 0) == 1) {
|
|
datafellows = check[i].bugs;
|
|
debug("match: %s pat %s compat 0x%08x",
|
|
version, check[i].pat, datafellows);
|
|
/*
|
|
* Check to see if the remote side is OpenSSH and not
|
|
* HPN. It is utterly strange to check it from the
|
|
* version string and expose the option that way.
|
|
*/
|
|
if (strstr(version,"OpenSSH") != NULL &&
|
|
strstr(version,"hpn") == NULL) {
|
|
datafellows |= SSH_BUG_LARGEWINDOW;
|
|
debug("Remote is not HPN-aware");
|
|
}
|
|
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:
|
|
logit("ignoring bad proto spec: '%s'.", p);
|
|
break;
|
|
}
|
|
}
|
|
free(s);
|
|
return ret;
|
|
}
|
|
|
|
/*
|
|
* Filters a proposal string, excluding any algorithm matching the 'filter'
|
|
* pattern list.
|
|
*/
|
|
static char *
|
|
filter_proposal(char *proposal, const char *filter)
|
|
{
|
|
Buffer b;
|
|
char *orig_prop, *fix_prop;
|
|
char *cp, *tmp;
|
|
|
|
buffer_init(&b);
|
|
tmp = orig_prop = xstrdup(proposal);
|
|
while ((cp = strsep(&tmp, ",")) != NULL) {
|
|
if (match_pattern_list(cp, filter, strlen(cp), 0) != 1) {
|
|
if (buffer_len(&b) > 0)
|
|
buffer_append(&b, ",", 1);
|
|
buffer_append(&b, cp, strlen(cp));
|
|
} else
|
|
debug2("Compat: skipping algorithm \"%s\"", cp);
|
|
}
|
|
buffer_append(&b, "\0", 1);
|
|
fix_prop = xstrdup(buffer_ptr(&b));
|
|
buffer_free(&b);
|
|
free(orig_prop);
|
|
|
|
return fix_prop;
|
|
}
|
|
|
|
char *
|
|
compat_cipher_proposal(char *cipher_prop)
|
|
{
|
|
if (!(datafellows & SSH_BUG_BIGENDIANAES))
|
|
return cipher_prop;
|
|
debug2("%s: original cipher proposal: %s", __func__, cipher_prop);
|
|
cipher_prop = filter_proposal(cipher_prop, "aes*");
|
|
debug2("%s: compat cipher proposal: %s", __func__, cipher_prop);
|
|
if (*cipher_prop == '\0')
|
|
fatal("No supported ciphers found");
|
|
return cipher_prop;
|
|
}
|
|
|
|
char *
|
|
compat_pkalg_proposal(char *pkalg_prop)
|
|
{
|
|
if (!(datafellows & SSH_BUG_RSASIGMD5))
|
|
return pkalg_prop;
|
|
debug2("%s: original public key proposal: %s", __func__, pkalg_prop);
|
|
pkalg_prop = filter_proposal(pkalg_prop, "ssh-rsa");
|
|
debug2("%s: compat public key proposal: %s", __func__, pkalg_prop);
|
|
if (*pkalg_prop == '\0')
|
|
fatal("No supported PK algorithms found");
|
|
return pkalg_prop;
|
|
}
|
|
|
|
char *
|
|
compat_kex_proposal(char *kex_prop)
|
|
{
|
|
if (!(datafellows & SSH_BUG_CURVE25519PAD))
|
|
return kex_prop;
|
|
debug2("%s: original KEX proposal: %s", __func__, kex_prop);
|
|
kex_prop = filter_proposal(kex_prop, "curve25519-sha256@libssh.org");
|
|
debug2("%s: compat KEX proposal: %s", __func__, kex_prop);
|
|
if (*kex_prop == '\0')
|
|
fatal("No supported key exchange algorithms found");
|
|
return kex_prop;
|
|
}
|
|
|