1/* $OpenBSD: compat.c,v 1.80 2012/08/17 01:30:00 djm Exp $ */ 2/* 3 * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26#include "includes.h" 27 28#include <sys/types.h> 29 30#include <stdlib.h> 31#include <string.h> 32#include <stdarg.h> 33 34#include "xmalloc.h" 35#include "buffer.h" 36#include "packet.h" 37#include "compat.h" 38#include "log.h" 39#include "match.h" 40 41int compat13 = 0; 42int compat20 = 0; 43int datafellows = 0; 44 45void 46enable_compat20(void) 47{ 48 if (compat20) 49 return; 50 debug("Enabling compatibility mode for protocol 2.0"); 51 compat20 = 1; 52} 53void 54enable_compat13(void) 55{ 56 debug("Enabling compatibility mode for protocol 1.3"); 57 compat13 = 1; 58} 59/* datafellows bug compatibility */ 60void 61compat_datafellows(const char *version) 62{ 63 int i; 64 static struct { 65 char *pat; 66 int bugs; 67 } check[] = { 68 { "OpenSSH-2.0*," 69 "OpenSSH-2.1*," 70 "OpenSSH_2.1*," 71 "OpenSSH_2.2*", SSH_OLD_SESSIONID|SSH_BUG_BANNER| 72 SSH_OLD_DHGEX|SSH_BUG_NOREKEY| 73 SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR}, 74 { "OpenSSH_2.3.0*", SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES| 75 SSH_OLD_DHGEX|SSH_BUG_NOREKEY| 76 SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR}, 77 { "OpenSSH_2.3.*", SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX| 78 SSH_BUG_NOREKEY|SSH_BUG_EXTEOF| 79 SSH_OLD_FORWARD_ADDR}, 80 { "OpenSSH_2.5.0p1*," 81 "OpenSSH_2.5.1p1*", 82 SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX| 83 SSH_BUG_NOREKEY|SSH_BUG_EXTEOF| 84 SSH_OLD_FORWARD_ADDR}, 85 { "OpenSSH_2.5.0*," 86 "OpenSSH_2.5.1*," 87 "OpenSSH_2.5.2*", SSH_OLD_DHGEX|SSH_BUG_NOREKEY| 88 SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR}, 89 { "OpenSSH_2.5.3*", SSH_BUG_NOREKEY|SSH_BUG_EXTEOF| 90 SSH_OLD_FORWARD_ADDR}, 91 { "OpenSSH_2.*," 92 "OpenSSH_3.0*," 93 "OpenSSH_3.1*", SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR}, 94 { "OpenSSH_3.*", SSH_OLD_FORWARD_ADDR }, 95 { "Sun_SSH_1.0*", SSH_BUG_NOREKEY|SSH_BUG_EXTEOF}, 96 { "OpenSSH_4*", 0 }, 97 { "OpenSSH_5*", SSH_NEW_OPENSSH|SSH_BUG_DYNAMIC_RPORT}, 98 { "OpenSSH*", SSH_NEW_OPENSSH }, 99 { "*MindTerm*", 0 }, 100 { "2.1.0*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 101 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 102 SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE| 103 SSH_BUG_FIRSTKEX }, 104 { "2.1 *", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 105 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 106 SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE| 107 SSH_BUG_FIRSTKEX }, 108 { "2.0.13*," 109 "2.0.14*," 110 "2.0.15*," 111 "2.0.16*," 112 "2.0.17*," 113 "2.0.18*," 114 "2.0.19*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 115 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 116 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 117 SSH_BUG_PKOK|SSH_BUG_RSASIGMD5| 118 SSH_BUG_HBSERVICE|SSH_BUG_OPENFAILURE| 119 SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX }, 120 { "2.0.11*," 121 "2.0.12*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 122 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 123 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 124 SSH_BUG_PKAUTH|SSH_BUG_PKOK| 125 SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE| 126 SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX }, 127 { "2.0.*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 128 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 129 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 130 SSH_BUG_PKAUTH|SSH_BUG_PKOK| 131 SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE| 132 SSH_BUG_DERIVEKEY|SSH_BUG_DUMMYCHAN| 133 SSH_BUG_FIRSTKEX }, 134 { "2.2.0*," 135 "2.3.0*", SSH_BUG_HMAC|SSH_BUG_DEBUG| 136 SSH_BUG_RSASIGMD5|SSH_BUG_FIRSTKEX }, 137 { "2.3.*", SSH_BUG_DEBUG|SSH_BUG_RSASIGMD5| 138 SSH_BUG_FIRSTKEX }, 139 { "2.4", SSH_OLD_SESSIONID }, /* Van Dyke */ 140 { "2.*", SSH_BUG_DEBUG|SSH_BUG_FIRSTKEX| 141 SSH_BUG_RFWD_ADDR }, 142 { "3.0.*", SSH_BUG_DEBUG }, 143 { "3.0 SecureCRT*", SSH_OLD_SESSIONID }, 144 { "1.7 SecureFX*", SSH_OLD_SESSIONID }, 145 { "1.2.18*," 146 "1.2.19*," 147 "1.2.20*," 148 "1.2.21*," 149 "1.2.22*", SSH_BUG_IGNOREMSG }, 150 { "1.3.2*", /* F-Secure */ 151 SSH_BUG_IGNOREMSG }, 152 { "*SSH Compatible Server*", /* Netscreen */ 153 SSH_BUG_PASSWORDPAD }, 154 { "*OSU_0*," 155 "OSU_1.0*," 156 "OSU_1.1*," 157 "OSU_1.2*," 158 "OSU_1.3*," 159 "OSU_1.4*," 160 "OSU_1.5alpha1*," 161 "OSU_1.5alpha2*," 162 "OSU_1.5alpha3*", SSH_BUG_PASSWORDPAD }, 163 { "*SSH_Version_Mapper*", 164 SSH_BUG_SCANNER }, 165 { "Probe-*", 166 SSH_BUG_PROBE }, 167 { NULL, 0 } 168 }; 169 170 /* process table, return first match */ 171 for (i = 0; check[i].pat; i++) { 172 if (match_pattern_list(version, check[i].pat, 173 strlen(check[i].pat), 0) == 1) { 174 debug("match: %s pat %s", version, check[i].pat); 175 datafellows = check[i].bugs; 176 return; 177 } 178 } 179 debug("no match: %s", version); 180} 181 182#define SEP "," 183int 184proto_spec(const char *spec) 185{ 186 char *s, *p, *q; 187 int ret = SSH_PROTO_UNKNOWN; 188 189 if (spec == NULL) 190 return ret; 191 q = s = xstrdup(spec); 192 for ((p = strsep(&q, SEP)); p && *p != '\0'; (p = strsep(&q, SEP))) { 193 switch (atoi(p)) { 194 case 1: 195 if (ret == SSH_PROTO_UNKNOWN) 196 ret |= SSH_PROTO_1_PREFERRED; 197 ret |= SSH_PROTO_1; 198 break; 199 case 2: 200 ret |= SSH_PROTO_2; 201 break; 202 default: 203 logit("ignoring bad proto spec: '%s'.", p); 204 break; 205 } 206 } 207 xfree(s); 208 return ret; 209} 210 211char * 212compat_cipher_proposal(char *cipher_prop) 213{ 214 Buffer b; 215 char *orig_prop, *fix_ciphers; 216 char *cp, *tmp; 217 218 if (!(datafellows & SSH_BUG_BIGENDIANAES)) 219 return(cipher_prop); 220 221 buffer_init(&b); 222 tmp = orig_prop = xstrdup(cipher_prop); 223 while ((cp = strsep(&tmp, ",")) != NULL) { 224 if (strncmp(cp, "aes", 3) != 0) { 225 if (buffer_len(&b) > 0) 226 buffer_append(&b, ",", 1); 227 buffer_append(&b, cp, strlen(cp)); 228 } 229 } 230 buffer_append(&b, "\0", 1); 231 fix_ciphers = xstrdup(buffer_ptr(&b)); 232 buffer_free(&b); 233 xfree(orig_prop); 234 debug2("Original cipher proposal: %s", cipher_prop); 235 debug2("Compat cipher proposal: %s", fix_ciphers); 236 if (!*fix_ciphers) 237 fatal("No available ciphers found."); 238 239 return(fix_ciphers); 240} 241