1 /* 2 * Copyright (c) 1999, 2000, 2001 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 1.58 2002/01/21 22:30:12 markus Exp $"); 27 28 #include "buffer.h" 29 #include "packet.h" 30 #include "xmalloc.h" 31 #include "compat.h" 32 #include "log.h" 33 #include "match.h" 34 35 int compat13 = 0; 36 int compat20 = 0; 37 int datafellows = 0; 38 39 void 40 enable_compat20(void) 41 { 42 verbose("Enabling compatibility mode for protocol 2.0"); 43 compat20 = 1; 44 } 45 void 46 enable_compat13(void) 47 { 48 verbose("Enabling compatibility mode for protocol 1.3"); 49 compat13 = 1; 50 } 51 /* datafellows bug compatibility */ 52 void 53 compat_datafellows(const char *version) 54 { 55 int i; 56 static struct { 57 char *pat; 58 int bugs; 59 } check[] = { 60 { "OpenSSH-2.0*," 61 "OpenSSH-2.1*," 62 "OpenSSH_2.1*," 63 "OpenSSH_2.2*", SSH_OLD_SESSIONID|SSH_BUG_BANNER| 64 SSH_OLD_DHGEX|SSH_BUG_NOREKEY }, 65 { "OpenSSH_2.3.0*", SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES| 66 SSH_OLD_DHGEX|SSH_BUG_NOREKEY}, 67 { "OpenSSH_2.3.*", SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX| 68 SSH_BUG_NOREKEY}, 69 { "OpenSSH_2.5.0p1*," 70 "OpenSSH_2.5.1p1*", 71 SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX| 72 SSH_BUG_NOREKEY }, 73 { "OpenSSH_2.5.0*," 74 "OpenSSH_2.5.1*," 75 "OpenSSH_2.5.2*", SSH_OLD_DHGEX|SSH_BUG_NOREKEY }, 76 { "OpenSSH_2.5.3*", 77 SSH_BUG_NOREKEY }, 78 { "OpenSSH*", 0 }, 79 { "*MindTerm*", 0 }, 80 { "2.1.0*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 81 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 82 SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE }, 83 { "2.1 *", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 84 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 85 SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE }, 86 { "2.0.13*," 87 "2.0.14*," 88 "2.0.15*," 89 "2.0.16*," 90 "2.0.17*," 91 "2.0.18*," 92 "2.0.19*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 93 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 94 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 95 SSH_BUG_PKOK|SSH_BUG_RSASIGMD5| 96 SSH_BUG_HBSERVICE|SSH_BUG_OPENFAILURE| 97 SSH_BUG_DUMMYCHAN }, 98 { "2.0.11*," 99 "2.0.12*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 100 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 101 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 102 SSH_BUG_PKAUTH|SSH_BUG_PKOK| 103 SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE| 104 SSH_BUG_DUMMYCHAN }, 105 { "2.0.*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 106 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 107 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 108 SSH_BUG_PKAUTH|SSH_BUG_PKOK| 109 SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE| 110 SSH_BUG_DERIVEKEY|SSH_BUG_DUMMYCHAN }, 111 { "2.2.0*," 112 "2.3.0*", SSH_BUG_HMAC|SSH_BUG_DEBUG| 113 SSH_BUG_RSASIGMD5 }, 114 { "2.3.*", SSH_BUG_DEBUG|SSH_BUG_RSASIGMD5 }, 115 { "2.4", SSH_OLD_SESSIONID }, /* Van Dyke */ 116 { "2.*", SSH_BUG_DEBUG }, 117 { "3.0.*", SSH_BUG_DEBUG }, 118 { "3.0 SecureCRT*", SSH_OLD_SESSIONID }, 119 { "1.7 SecureFX*", SSH_OLD_SESSIONID }, 120 { "1.2.18*," 121 "1.2.19*," 122 "1.2.20*," 123 "1.2.21*," 124 "1.2.22*", SSH_BUG_IGNOREMSG }, 125 { "1.3.2*", SSH_BUG_IGNOREMSG }, /* f-secure */ 126 { "*SSH Compatible Server*", /* Netscreen */ 127 SSH_BUG_PASSWORDPAD }, 128 { "*OSU_0*," 129 "OSU_1.0*," 130 "OSU_1.1*," 131 "OSU_1.2*," 132 "OSU_1.3*," 133 "OSU_1.4*," 134 "OSU_1.5alpha1*," 135 "OSU_1.5alpha2*," 136 "OSU_1.5alpha3*", SSH_BUG_PASSWORDPAD }, 137 { "*SSH_Version_Mapper*", 138 SSH_BUG_SCANNER }, 139 { NULL, 0 } 140 }; 141 142 /* process table, return first match */ 143 for (i = 0; check[i].pat; i++) { 144 if (match_pattern_list(version, check[i].pat, 145 strlen(check[i].pat), 0) == 1) { 146 debug("match: %s pat %s", version, check[i].pat); 147 datafellows = check[i].bugs; 148 return; 149 } 150 } 151 debug("no match: %s", version); 152 } 153 154 #define SEP "," 155 int 156 proto_spec(const char *spec) 157 { 158 char *s, *p, *q; 159 int ret = SSH_PROTO_UNKNOWN; 160 161 if (spec == NULL) 162 return ret; 163 q = s = xstrdup(spec); 164 for ((p = strsep(&q, SEP)); p && *p != '\0'; (p = strsep(&q, SEP))) { 165 switch (atoi(p)) { 166 case 1: 167 if (ret == SSH_PROTO_UNKNOWN) 168 ret |= SSH_PROTO_1_PREFERRED; 169 ret |= SSH_PROTO_1; 170 break; 171 case 2: 172 ret |= SSH_PROTO_2; 173 break; 174 default: 175 log("ignoring bad proto spec: '%s'.", p); 176 break; 177 } 178 } 179 xfree(s); 180 return ret; 181 } 182 183 char * 184 compat_cipher_proposal(char *cipher_prop) 185 { 186 Buffer b; 187 char *orig_prop, *fix_ciphers; 188 char *cp, *tmp; 189 190 if (!(datafellows & SSH_BUG_BIGENDIANAES)) 191 return(cipher_prop); 192 193 buffer_init(&b); 194 tmp = orig_prop = xstrdup(cipher_prop); 195 while ((cp = strsep(&tmp, ",")) != NULL) { 196 if (strncmp(cp, "aes", 3) != 0) { 197 if (buffer_len(&b) > 0) 198 buffer_append(&b, ",", 1); 199 buffer_append(&b, cp, strlen(cp)); 200 } 201 } 202 buffer_append(&b, "\0", 1); 203 fix_ciphers = xstrdup(buffer_ptr(&b)); 204 buffer_free(&b); 205 xfree(orig_prop); 206 debug2("Original cipher proposal: %s", cipher_prop); 207 debug2("Compat cipher proposal: %s", fix_ciphers); 208 if (!*fix_ciphers) 209 fatal("No available ciphers found."); 210 211 return(fix_ciphers); 212 } 213