1 /* 2 * Copyright (c) 1999, 2000, 2001, 2002 Markus Friedl. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 23 */ 24 25 #include "includes.h" 26 RCSID("$OpenBSD: compat.c,v 1.71 2005/03/01 10:09:52 djm Exp $"); 27 RCSID("$FreeBSD$"); 28 29 #include "buffer.h" 30 #include "packet.h" 31 #include "xmalloc.h" 32 #include "compat.h" 33 #include "log.h" 34 #include "match.h" 35 36 int compat13 = 0; 37 int compat20 = 0; 38 int datafellows = 0; 39 40 void 41 enable_compat20(void) 42 { 43 debug("Enabling compatibility mode for protocol 2.0"); 44 compat20 = 1; 45 } 46 void 47 enable_compat13(void) 48 { 49 debug("Enabling compatibility mode for protocol 1.3"); 50 compat13 = 1; 51 } 52 /* datafellows bug compatibility */ 53 void 54 compat_datafellows(const char *version) 55 { 56 int i; 57 static struct { 58 char *pat; 59 int bugs; 60 } check[] = { 61 { "OpenSSH-2.0*," 62 "OpenSSH-2.1*," 63 "OpenSSH_2.1*," 64 "OpenSSH_2.2*", SSH_OLD_SESSIONID|SSH_BUG_BANNER| 65 SSH_OLD_DHGEX|SSH_BUG_NOREKEY| 66 SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR}, 67 { "OpenSSH_2.3.0*", SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES| 68 SSH_OLD_DHGEX|SSH_BUG_NOREKEY| 69 SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR}, 70 { "OpenSSH_2.3.*", SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX| 71 SSH_BUG_NOREKEY|SSH_BUG_EXTEOF| 72 SSH_OLD_FORWARD_ADDR}, 73 { "OpenSSH_2.5.0p1*," 74 "OpenSSH_2.5.1p1*", 75 SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX| 76 SSH_BUG_NOREKEY|SSH_BUG_EXTEOF| 77 SSH_OLD_FORWARD_ADDR}, 78 { "OpenSSH_2.5.0*," 79 "OpenSSH_2.5.1*," 80 "OpenSSH_2.5.2*", SSH_OLD_DHGEX|SSH_BUG_NOREKEY| 81 SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR}, 82 { "OpenSSH_2.5.3*", SSH_BUG_NOREKEY|SSH_BUG_EXTEOF| 83 SSH_OLD_FORWARD_ADDR}, 84 { "OpenSSH_2.*," 85 "OpenSSH_3.0*," 86 "OpenSSH_3.1*", SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR}, 87 { "OpenSSH_3.*", SSH_OLD_FORWARD_ADDR }, 88 { "Sun_SSH_1.0*", SSH_BUG_NOREKEY|SSH_BUG_EXTEOF}, 89 { "OpenSSH*", 0 }, 90 { "*MindTerm*", 0 }, 91 { "2.1.0*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 92 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 93 SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE| 94 SSH_BUG_FIRSTKEX }, 95 { "2.1 *", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 96 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 97 SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE| 98 SSH_BUG_FIRSTKEX }, 99 { "2.0.13*," 100 "2.0.14*," 101 "2.0.15*," 102 "2.0.16*," 103 "2.0.17*," 104 "2.0.18*," 105 "2.0.19*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 106 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 107 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 108 SSH_BUG_PKOK|SSH_BUG_RSASIGMD5| 109 SSH_BUG_HBSERVICE|SSH_BUG_OPENFAILURE| 110 SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX }, 111 { "2.0.11*," 112 "2.0.12*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 113 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 114 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 115 SSH_BUG_PKAUTH|SSH_BUG_PKOK| 116 SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE| 117 SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX }, 118 { "2.0.*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 119 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 120 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 121 SSH_BUG_PKAUTH|SSH_BUG_PKOK| 122 SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE| 123 SSH_BUG_DERIVEKEY|SSH_BUG_DUMMYCHAN| 124 SSH_BUG_FIRSTKEX }, 125 { "2.2.0*," 126 "2.3.0*", SSH_BUG_HMAC|SSH_BUG_DEBUG| 127 SSH_BUG_RSASIGMD5|SSH_BUG_FIRSTKEX }, 128 { "2.3.*", SSH_BUG_DEBUG|SSH_BUG_RSASIGMD5| 129 SSH_BUG_FIRSTKEX }, 130 { "2.4", SSH_OLD_SESSIONID }, /* Van Dyke */ 131 { "2.*", SSH_BUG_DEBUG|SSH_BUG_FIRSTKEX }, 132 { "3.0.*", SSH_BUG_DEBUG }, 133 { "3.0 SecureCRT*", SSH_OLD_SESSIONID }, 134 { "1.7 SecureFX*", SSH_OLD_SESSIONID }, 135 { "1.2.18*," 136 "1.2.19*," 137 "1.2.20*," 138 "1.2.21*," 139 "1.2.22*", SSH_BUG_IGNOREMSG }, 140 { "1.3.2*", /* F-Secure */ 141 SSH_BUG_IGNOREMSG }, 142 { "*SSH Compatible Server*", /* Netscreen */ 143 SSH_BUG_PASSWORDPAD }, 144 { "*OSU_0*," 145 "OSU_1.0*," 146 "OSU_1.1*," 147 "OSU_1.2*," 148 "OSU_1.3*," 149 "OSU_1.4*," 150 "OSU_1.5alpha1*," 151 "OSU_1.5alpha2*," 152 "OSU_1.5alpha3*", SSH_BUG_PASSWORDPAD }, 153 { "*SSH_Version_Mapper*", 154 SSH_BUG_SCANNER }, 155 { "Probe-*", 156 SSH_BUG_PROBE }, 157 { NULL, 0 } 158 }; 159 160 /* process table, return first match */ 161 for (i = 0; check[i].pat; i++) { 162 if (match_pattern_list(version, check[i].pat, 163 strlen(check[i].pat), 0) == 1) { 164 debug("match: %s pat %s", version, check[i].pat); 165 datafellows = check[i].bugs; 166 return; 167 } 168 } 169 debug("no match: %s", version); 170 } 171 172 #define SEP "," 173 int 174 proto_spec(const char *spec) 175 { 176 char *s, *p, *q; 177 int ret = SSH_PROTO_UNKNOWN; 178 179 if (spec == NULL) 180 return ret; 181 q = s = xstrdup(spec); 182 for ((p = strsep(&q, SEP)); p && *p != '\0'; (p = strsep(&q, SEP))) { 183 switch (atoi(p)) { 184 case 1: 185 if (ret == SSH_PROTO_UNKNOWN) 186 ret |= SSH_PROTO_1_PREFERRED; 187 ret |= SSH_PROTO_1; 188 break; 189 case 2: 190 ret |= SSH_PROTO_2; 191 break; 192 default: 193 logit("ignoring bad proto spec: '%s'.", p); 194 break; 195 } 196 } 197 xfree(s); 198 return ret; 199 } 200 201 char * 202 compat_cipher_proposal(char *cipher_prop) 203 { 204 Buffer b; 205 char *orig_prop, *fix_ciphers; 206 char *cp, *tmp; 207 208 if (!(datafellows & SSH_BUG_BIGENDIANAES)) 209 return(cipher_prop); 210 211 buffer_init(&b); 212 tmp = orig_prop = xstrdup(cipher_prop); 213 while ((cp = strsep(&tmp, ",")) != NULL) { 214 if (strncmp(cp, "aes", 3) != 0) { 215 if (buffer_len(&b) > 0) 216 buffer_append(&b, ",", 1); 217 buffer_append(&b, cp, strlen(cp)); 218 } 219 } 220 buffer_append(&b, "\0", 1); 221 fix_ciphers = xstrdup(buffer_ptr(&b)); 222 buffer_free(&b); 223 xfree(orig_prop); 224 debug2("Original cipher proposal: %s", cipher_prop); 225 debug2("Compat cipher proposal: %s", fix_ciphers); 226 if (!*fix_ciphers) 227 fatal("No available ciphers found."); 228 229 return(fix_ciphers); 230 } 231