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  * Copyright 2009 Sun Microsystems, Inc.  All rights reserved.
  26  * Use is subject to license terms.
  27  */
  28 
  29 #include "includes.h"
  30 RCSID("$OpenBSD: compat.c,v 1.65 2002/09/27 10:42:09 mickey Exp $");
  31 
  32 #include "buffer.h"
  33 #include "packet.h"
  34 #include "xmalloc.h"
  35 #include "compat.h"
  36 #include "log.h"
  37 #include "match.h"
  38 
  39 int compat13 = 0;
  40 int compat20 = 0;
  41 uint32_t datafellows = 0;
  42 
  43 void
  44 enable_compat20(void)
  45 {
  46         debug("Enabling compatibility mode for protocol 2.0");
  47         compat20 = 1;
  48 }
  49 void
  50 enable_compat13(void)
  51 {
  52         debug("Enabling compatibility mode for protocol 1.3");
  53         compat13 = 1;
  54 }
  55 /* datafellows bug compatibility */
  56 void
  57 compat_datafellows(const char *version)
  58 {
  59         int i;
  60         static struct {
  61                 char    *pat;
  62                 uint32_t bugs;
  63         } check[] = {
  64                 { "OpenSSH-2.0*,"
  65                   "OpenSSH-2.1*,"
  66                   "OpenSSH_2.1*,"
  67                   "OpenSSH_2.2*",       SSH_OLD_SESSIONID|SSH_BUG_BANNER|
  68                                         SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
  69                                         SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
  70                 { "OpenSSH_2.3.0*",     SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES|
  71                                         SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
  72                                         SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
  73                 { "OpenSSH_2.3.*",      SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
  74                                         SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
  75                                         SSH_OLD_FORWARD_ADDR},
  76                 { "OpenSSH_2.5.0p1*,"
  77                   "OpenSSH_2.5.1p1*",
  78                                         SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
  79                                         SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
  80                                         SSH_OLD_GSSAPI|SSH_OLD_FORWARD_ADDR},
  81                 { "OpenSSH_2.5.0*,"
  82                   "OpenSSH_2.5.1*,"
  83                   "OpenSSH_2.5.2*",     SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
  84                                         SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
  85                 { "OpenSSH_2.5.3*",     SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
  86                                         SSH_OLD_FORWARD_ADDR},
  87                 { "OpenSSH_2.9p*",      SSH_BUG_EXTEOF|SSH_OLD_GSSAPI|
  88                                         SSH_BUG_GSSKEX_HOSTKEY|SSH_OLD_FORWARD_ADDR},
  89                 { "OpenSSH_2.*,"
  90                   "OpenSSH_3.0*,"
  91                   "OpenSSH_3.1*",       SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR|
  92                                         SSH_OLD_GSSAPI|SSH_BUG_GSSAPI_BER|
  93                                         SSH_BUG_GSSKEX_HOSTKEY},
  94                 { "OpenSSH_3.2*,"
  95                   "OpenSSH_3.3*,"
  96                   "OpenSSH_3.4*,"
  97                   "OpenSSH_3.5*",       SSH_BUG_GSSAPI_BER|SSH_OLD_GSSAPI|
  98                                         SSH_BUG_GSSKEX_HOSTKEY|SSH_OLD_FORWARD_ADDR},
  99                 { "OpenSSH_3.6*,"
 100                   "OpenSSH_3.7*,"
 101                   "OpenSSH_3.8*",       SSH_BUG_GSSKEX_HOSTKEY|SSH_OLD_FORWARD_ADDR},
 102                 { "OpenSSH_3.*",        SSH_OLD_FORWARD_ADDR},
 103                 { "OpenSSH*",           0 },
 104                 { "Sun_SSH_1.0.*",      SSH_BUG_NOREKEY|
 105                                         SSH_BUG_LOCALES_NOT_LANGTAGS|SSH_OLD_FORWARD_ADDR},
 106                 { "Sun_SSH_1.0*",       SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
 107                                         SSH_BUG_LOCALES_NOT_LANGTAGS|SSH_OLD_FORWARD_ADDR},
 108                 { "Sun_SSH_1.1.1*",     SSH_OLD_FORWARD_ADDR|SSH_BUG_STRING_ENCODING},
 109                 { "Sun_SSH_1.1.2*",     SSH_OLD_FORWARD_ADDR},
 110                 { "Sun_SSH_1.1*",       SSH_OLD_FORWARD_ADDR|SSH_BUG_STRING_ENCODING},
 111                 { "Sun_SSH_1.2*",       SSH_BUG_STRING_ENCODING},
 112                 { "Sun_SSH_1.3*",       SSH_BUG_STRING_ENCODING},
 113                 { "Sun_SSH_1.4*",       0 },
 114                 { "Sun_SSH_1.5*",       0 },
 115                 { "Sun_SSH_*",          0 },
 116                 { "*MindTerm*",         0 },
 117                 { "2.1.0*",             SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
 118                                         SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
 119                                         SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE|
 120                                         SSH_BUG_FIRSTKEX },
 121                 { "2.1 *",              SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
 122                                         SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
 123                                         SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE|
 124                                         SSH_BUG_FIRSTKEX },
 125                 { "2.0.13*,"
 126                   "2.0.14*,"
 127                   "2.0.15*,"
 128                   "2.0.16*,"
 129                   "2.0.17*,"
 130                   "2.0.18*,"
 131                   "2.0.19*",            SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
 132                                         SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
 133                                         SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
 134                                         SSH_BUG_PKOK|SSH_BUG_RSASIGMD5|
 135                                         SSH_BUG_HBSERVICE|SSH_BUG_OPENFAILURE|
 136                                         SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX },
 137                 { "2.0.11*,"
 138                   "2.0.12*",            SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
 139                                         SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
 140                                         SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
 141                                         SSH_BUG_PKAUTH|SSH_BUG_PKOK|
 142                                         SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE|
 143                                         SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX },
 144                 { "2.0.*",              SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
 145                                         SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
 146                                         SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
 147                                         SSH_BUG_PKAUTH|SSH_BUG_PKOK|
 148                                         SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE|
 149                                         SSH_BUG_DERIVEKEY|SSH_BUG_DUMMYCHAN|
 150                                         SSH_BUG_FIRSTKEX },
 151                 { "2.2.0*,"
 152                   "2.3.0*",             SSH_BUG_HMAC|SSH_BUG_DEBUG|
 153                                         SSH_BUG_RSASIGMD5|SSH_BUG_FIRSTKEX },
 154                 { "2.3.*",              SSH_BUG_DEBUG|SSH_BUG_RSASIGMD5|
 155                                         SSH_BUG_FIRSTKEX },
 156                 { "2.4",                SSH_OLD_SESSIONID },    /* Van Dyke */
 157                 { "2.*",                SSH_BUG_DEBUG|SSH_BUG_FIRSTKEX|
 158                                         SSH_BUG_RFWD_ADDR},
 159                 { "3.0.*",              SSH_BUG_DEBUG },
 160                 { "3.0 SecureCRT*",     SSH_OLD_SESSIONID },
 161                 { "1.7 SecureFX*",      SSH_OLD_SESSIONID },
 162                 { "1.2.18*,"
 163                   "1.2.19*,"
 164                   "1.2.20*,"
 165                   "1.2.21*,"
 166                   "1.2.22*",            SSH_BUG_IGNOREMSG|SSH_BUG_K5USER },
 167                 { "1.3.2*",             /* F-Secure */
 168                                         SSH_BUG_IGNOREMSG|SSH_BUG_K5USER },
 169                 { "1.2.1*,"
 170                   "1.2.2*,"
 171                   "1.2.3*",             SSH_BUG_K5USER },
 172                 { "*SSH Compatible Server*",                    /* Netscreen */
 173                                         SSH_BUG_PASSWORDPAD },
 174                 { "*OSU_0*,"
 175                   "OSU_1.0*,"
 176                   "OSU_1.1*,"
 177                   "OSU_1.2*,"
 178                   "OSU_1.3*,"
 179                   "OSU_1.4*,"
 180                   "OSU_1.5alpha1*,"
 181                   "OSU_1.5alpha2*,"
 182                   "OSU_1.5alpha3*",     SSH_BUG_PASSWORDPAD },
 183                 { "*SSH_Version_Mapper*",
 184                                         SSH_BUG_SCANNER },
 185                 { "Probe-*",
 186                                         SSH_BUG_PROBE },
 187                 { NULL,                 0 }
 188         };
 189 
 190         /* process table, return first match */
 191         for (i = 0; check[i].pat; i++) {
 192                 if (match_pattern_list(version, check[i].pat,
 193                     strlen(check[i].pat), 0) == 1) {
 194                         debug("match: %s pat %s", version, check[i].pat);
 195                         datafellows = check[i].bugs;
 196                         return;
 197                 }
 198         }
 199         debug("no match: %s", version);
 200 }
 201 
 202 #define SEP     ","
 203 int
 204 proto_spec(const char *spec)
 205 {
 206         char *s, *p, *q;
 207         int ret = SSH_PROTO_UNKNOWN;
 208 
 209         if (spec == NULL)
 210                 return ret;
 211         q = s = xstrdup(spec);
 212         for ((p = strsep(&q, SEP)); p && *p != '\0'; (p = strsep(&q, SEP))) {
 213                 switch (atoi(p)) {
 214                 case 1:
 215                         if (ret == SSH_PROTO_UNKNOWN)
 216                                 ret |= SSH_PROTO_1_PREFERRED;
 217                         ret |= SSH_PROTO_1;
 218                         break;
 219                 case 2:
 220                         ret |= SSH_PROTO_2;
 221                         break;
 222                 default:
 223                         log("ignoring bad proto spec: '%s'.", p);
 224                         break;
 225                 }
 226         }
 227         xfree(s);
 228         return ret;
 229 }
 230 
 231 char *
 232 compat_cipher_proposal(char *cipher_prop)
 233 {
 234         Buffer b;
 235         char *orig_prop, *fix_ciphers;
 236         char *cp, *tmp;
 237 
 238         if (!(datafellows & SSH_BUG_BIGENDIANAES))
 239                 return(cipher_prop);
 240 
 241         buffer_init(&b);
 242         tmp = orig_prop = xstrdup(cipher_prop);
 243         while ((cp = strsep(&tmp, ",")) != NULL) {
 244                 if (strncmp(cp, "aes", 3) != 0) {
 245                         if (buffer_len(&b) > 0)
 246                                 buffer_append(&b, ",", 1);
 247                         buffer_append(&b, cp, strlen(cp));
 248                 }
 249         }
 250         buffer_append(&b, "\0", 1);
 251         fix_ciphers = xstrdup(buffer_ptr(&b));
 252         buffer_free(&b);
 253         xfree(orig_prop);
 254         debug2("Original cipher proposal: %s", cipher_prop);
 255         debug2("Compat cipher proposal: %s", fix_ciphers);
 256         if (!*fix_ciphers)
 257                 fatal("No available ciphers found.");
 258 
 259         return(fix_ciphers);
 260 }