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 1.66 2003/04/01 10:31:26 markus 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}, 67 { "OpenSSH_2.3.0*", SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES| 68 SSH_OLD_DHGEX|SSH_BUG_NOREKEY| 69 SSH_BUG_EXTEOF}, 70 { "OpenSSH_2.3.*", SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX| 71 SSH_BUG_NOREKEY|SSH_BUG_EXTEOF}, 72 { "OpenSSH_2.5.0p1*," 73 "OpenSSH_2.5.1p1*", 74 SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX| 75 SSH_BUG_NOREKEY|SSH_BUG_EXTEOF}, 76 { "OpenSSH_2.5.0*," 77 "OpenSSH_2.5.1*," 78 "OpenSSH_2.5.2*", SSH_OLD_DHGEX|SSH_BUG_NOREKEY| 79 SSH_BUG_EXTEOF}, 80 { "OpenSSH_2.5.3*", SSH_BUG_NOREKEY|SSH_BUG_EXTEOF}, 81 { "OpenSSH_2.*," 82 "OpenSSH_3.0*," 83 "OpenSSH_3.1*", SSH_BUG_EXTEOF}, 84 { "Sun_SSH_1.0*", SSH_BUG_NOREKEY|SSH_BUG_EXTEOF}, 85 { "OpenSSH*", 0 }, 86 { "*MindTerm*", 0 }, 87 { "2.1.0*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 88 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 89 SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE| 90 SSH_BUG_FIRSTKEX }, 91 { "2.1 *", 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 { "2.0.13*," 96 "2.0.14*," 97 "2.0.15*," 98 "2.0.16*," 99 "2.0.17*," 100 "2.0.18*," 101 "2.0.19*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 102 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 103 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 104 SSH_BUG_PKOK|SSH_BUG_RSASIGMD5| 105 SSH_BUG_HBSERVICE|SSH_BUG_OPENFAILURE| 106 SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX }, 107 { "2.0.11*," 108 "2.0.12*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 109 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 110 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 111 SSH_BUG_PKAUTH|SSH_BUG_PKOK| 112 SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE| 113 SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX }, 114 { "2.0.*", SSH_BUG_SIGBLOB|SSH_BUG_HMAC| 115 SSH_OLD_SESSIONID|SSH_BUG_DEBUG| 116 SSH_BUG_PKSERVICE|SSH_BUG_X11FWD| 117 SSH_BUG_PKAUTH|SSH_BUG_PKOK| 118 SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE| 119 SSH_BUG_DERIVEKEY|SSH_BUG_DUMMYCHAN| 120 SSH_BUG_FIRSTKEX }, 121 { "2.2.0*," 122 "2.3.0*", SSH_BUG_HMAC|SSH_BUG_DEBUG| 123 SSH_BUG_RSASIGMD5|SSH_BUG_FIRSTKEX }, 124 { "2.3.*", SSH_BUG_DEBUG|SSH_BUG_RSASIGMD5| 125 SSH_BUG_FIRSTKEX }, 126 { "2.4", SSH_OLD_SESSIONID }, /* Van Dyke */ 127 { "2.*", SSH_BUG_DEBUG|SSH_BUG_FIRSTKEX }, 128 { "3.0.*", SSH_BUG_DEBUG }, 129 { "3.0 SecureCRT*", SSH_OLD_SESSIONID }, 130 { "1.7 SecureFX*", SSH_OLD_SESSIONID }, 131 { "1.2.18*," 132 "1.2.19*," 133 "1.2.20*," 134 "1.2.21*," 135 "1.2.22*", SSH_BUG_IGNOREMSG|SSH_BUG_K5USER }, 136 { "1.3.2*", /* F-Secure */ 137 SSH_BUG_IGNOREMSG|SSH_BUG_K5USER }, 138 { "1.2.1*," 139 "1.2.2*," 140 "1.2.3*", SSH_BUG_K5USER }, 141 { "*SSH Compatible Server*", /* Netscreen */ 142 SSH_BUG_PASSWORDPAD }, 143 { "*OSU_0*," 144 "OSU_1.0*," 145 "OSU_1.1*," 146 "OSU_1.2*," 147 "OSU_1.3*," 148 "OSU_1.4*," 149 "OSU_1.5alpha1*," 150 "OSU_1.5alpha2*," 151 "OSU_1.5alpha3*", SSH_BUG_PASSWORDPAD }, 152 { "*SSH_Version_Mapper*", 153 SSH_BUG_SCANNER }, 154 { "Probe-*", 155 SSH_BUG_PROBE }, 156 { NULL, 0 } 157 }; 158 159 /* process table, return first match */ 160 for (i = 0; check[i].pat; i++) { 161 if (match_pattern_list(version, check[i].pat, 162 strlen(check[i].pat), 0) == 1) { 163 debug("match: %s pat %s", version, check[i].pat); 164 datafellows = check[i].bugs; 165 return; 166 } 167 } 168 debug("no match: %s", version); 169 } 170 171 #define SEP "," 172 int 173 proto_spec(const char *spec) 174 { 175 char *s, *p, *q; 176 int ret = SSH_PROTO_UNKNOWN; 177 178 if (spec == NULL) 179 return ret; 180 q = s = xstrdup(spec); 181 for ((p = strsep(&q, SEP)); p && *p != '\0'; (p = strsep(&q, SEP))) { 182 switch (atoi(p)) { 183 case 1: 184 if (ret == SSH_PROTO_UNKNOWN) 185 ret |= SSH_PROTO_1_PREFERRED; 186 ret |= SSH_PROTO_1; 187 break; 188 case 2: 189 ret |= SSH_PROTO_2; 190 break; 191 default: 192 log("ignoring bad proto spec: '%s'.", p); 193 break; 194 } 195 } 196 xfree(s); 197 return ret; 198 } 199 200 char * 201 compat_cipher_proposal(char *cipher_prop) 202 { 203 Buffer b; 204 char *orig_prop, *fix_ciphers; 205 char *cp, *tmp; 206 207 if (!(datafellows & SSH_BUG_BIGENDIANAES)) 208 return(cipher_prop); 209 210 buffer_init(&b); 211 tmp = orig_prop = xstrdup(cipher_prop); 212 while ((cp = strsep(&tmp, ",")) != NULL) { 213 if (strncmp(cp, "aes", 3) != 0) { 214 if (buffer_len(&b) > 0) 215 buffer_append(&b, ",", 1); 216 buffer_append(&b, cp, strlen(cp)); 217 } 218 } 219 buffer_append(&b, "\0", 1); 220 fix_ciphers = xstrdup(buffer_ptr(&b)); 221 buffer_free(&b); 222 xfree(orig_prop); 223 debug2("Original cipher proposal: %s", cipher_prop); 224 debug2("Compat cipher proposal: %s", fix_ciphers); 225 if (!*fix_ciphers) 226 fatal("No available ciphers found."); 227 228 return(fix_ciphers); 229 } 230