Merge branch 'vendor/OPENSSH'
[dragonfly.git] / crypto / openssh / compat.c
1 /* $OpenBSD: compat.c,v 1.79 2011/09/23 07:45:05 markus 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
41 int compat13 = 0;
42 int compat20 = 0;
43 int datafellows = 0;
44
45 void
46 enable_compat20(void)
47 {
48         debug("Enabling compatibility mode for protocol 2.0");
49         compat20 = 1;
50 }
51 void
52 enable_compat13(void)
53 {
54         debug("Enabling compatibility mode for protocol 1.3");
55         compat13 = 1;
56 }
57 /* datafellows bug compatibility */
58 void
59 compat_datafellows(const char *version)
60 {
61         int i;
62         static struct {
63                 char    *pat;
64                 int     bugs;
65         } check[] = {
66                 { "OpenSSH-2.0*,"
67                   "OpenSSH-2.1*,"
68                   "OpenSSH_2.1*,"
69                   "OpenSSH_2.2*",       SSH_OLD_SESSIONID|SSH_BUG_BANNER|
70                                         SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
71                                         SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
72                 { "OpenSSH_2.3.0*",     SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES|
73                                         SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
74                                         SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
75                 { "OpenSSH_2.3.*",      SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
76                                         SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
77                                         SSH_OLD_FORWARD_ADDR},
78                 { "OpenSSH_2.5.0p1*,"
79                   "OpenSSH_2.5.1p1*",
80                                         SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX|
81                                         SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
82                                         SSH_OLD_FORWARD_ADDR},
83                 { "OpenSSH_2.5.0*,"
84                   "OpenSSH_2.5.1*,"
85                   "OpenSSH_2.5.2*",     SSH_OLD_DHGEX|SSH_BUG_NOREKEY|
86                                         SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
87                 { "OpenSSH_2.5.3*",     SSH_BUG_NOREKEY|SSH_BUG_EXTEOF|
88                                         SSH_OLD_FORWARD_ADDR},
89                 { "OpenSSH_2.*,"
90                   "OpenSSH_3.0*,"
91                   "OpenSSH_3.1*",       SSH_BUG_EXTEOF|SSH_OLD_FORWARD_ADDR},
92                 { "OpenSSH_3.*",        SSH_OLD_FORWARD_ADDR },
93                 { "Sun_SSH_1.0*",       SSH_BUG_NOREKEY|SSH_BUG_EXTEOF},
94                 { "OpenSSH_4*",         0 },
95                 { "OpenSSH_5*",         SSH_NEW_OPENSSH|SSH_BUG_DYNAMIC_RPORT},
96                 { "OpenSSH*",           SSH_NEW_OPENSSH },
97                 { "*MindTerm*",         0 },
98                 { "2.1.0*",             SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
99                                         SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
100                                         SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE|
101                                         SSH_BUG_FIRSTKEX },
102                 { "2.1 *",              SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
103                                         SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
104                                         SSH_BUG_RSASIGMD5|SSH_BUG_HBSERVICE|
105                                         SSH_BUG_FIRSTKEX },
106                 { "2.0.13*,"
107                   "2.0.14*,"
108                   "2.0.15*,"
109                   "2.0.16*,"
110                   "2.0.17*,"
111                   "2.0.18*,"
112                   "2.0.19*",            SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
113                                         SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
114                                         SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
115                                         SSH_BUG_PKOK|SSH_BUG_RSASIGMD5|
116                                         SSH_BUG_HBSERVICE|SSH_BUG_OPENFAILURE|
117                                         SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX },
118                 { "2.0.11*,"
119                   "2.0.12*",            SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
120                                         SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
121                                         SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
122                                         SSH_BUG_PKAUTH|SSH_BUG_PKOK|
123                                         SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE|
124                                         SSH_BUG_DUMMYCHAN|SSH_BUG_FIRSTKEX },
125                 { "2.0.*",              SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
126                                         SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
127                                         SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
128                                         SSH_BUG_PKAUTH|SSH_BUG_PKOK|
129                                         SSH_BUG_RSASIGMD5|SSH_BUG_OPENFAILURE|
130                                         SSH_BUG_DERIVEKEY|SSH_BUG_DUMMYCHAN|
131                                         SSH_BUG_FIRSTKEX },
132                 { "2.2.0*,"
133                   "2.3.0*",             SSH_BUG_HMAC|SSH_BUG_DEBUG|
134                                         SSH_BUG_RSASIGMD5|SSH_BUG_FIRSTKEX },
135                 { "2.3.*",              SSH_BUG_DEBUG|SSH_BUG_RSASIGMD5|
136                                         SSH_BUG_FIRSTKEX },
137                 { "2.4",                SSH_OLD_SESSIONID },    /* Van Dyke */
138                 { "2.*",                SSH_BUG_DEBUG|SSH_BUG_FIRSTKEX|
139                                         SSH_BUG_RFWD_ADDR },
140                 { "3.0.*",              SSH_BUG_DEBUG },
141                 { "3.0 SecureCRT*",     SSH_OLD_SESSIONID },
142                 { "1.7 SecureFX*",      SSH_OLD_SESSIONID },
143                 { "1.2.18*,"
144                   "1.2.19*,"
145                   "1.2.20*,"
146                   "1.2.21*,"
147                   "1.2.22*",            SSH_BUG_IGNOREMSG },
148                 { "1.3.2*",             /* F-Secure */
149                                         SSH_BUG_IGNOREMSG },
150                 { "*SSH Compatible Server*",                    /* Netscreen */
151                                         SSH_BUG_PASSWORDPAD },
152                 { "*OSU_0*,"
153                   "OSU_1.0*,"
154                   "OSU_1.1*,"
155                   "OSU_1.2*,"
156                   "OSU_1.3*,"
157                   "OSU_1.4*,"
158                   "OSU_1.5alpha1*,"
159                   "OSU_1.5alpha2*,"
160                   "OSU_1.5alpha3*",     SSH_BUG_PASSWORDPAD },
161                 { "*SSH_Version_Mapper*",
162                                         SSH_BUG_SCANNER },
163                 { "Probe-*",
164                                         SSH_BUG_PROBE },
165                 { NULL,                 0 }
166         };
167
168         /* process table, return first match */
169         for (i = 0; check[i].pat; i++) {
170                 if (match_pattern_list(version, check[i].pat,
171                     strlen(check[i].pat), 0) == 1) {
172                         debug("match: %s pat %s", version, check[i].pat);
173                         datafellows = check[i].bugs;
174                         /* Check to see if the remote side is OpenSSH and not HPN */
175                         if(strstr(version,"OpenSSH") != NULL)
176                         {
177                                 if (strstr(version,"hpn") == NULL)
178                                 {
179                                         datafellows |= SSH_BUG_LARGEWINDOW;
180                                         debug("Remote is NON-HPN aware");
181                                 }
182                         }
183                         return;
184                 }
185         }
186         debug("no match: %s", version);
187 }
188
189 #define SEP     ","
190 int
191 proto_spec(const char *spec)
192 {
193         char *s, *p, *q;
194         int ret = SSH_PROTO_UNKNOWN;
195
196         if (spec == NULL)
197                 return ret;
198         q = s = xstrdup(spec);
199         for ((p = strsep(&q, SEP)); p && *p != '\0'; (p = strsep(&q, SEP))) {
200                 switch (atoi(p)) {
201                 case 1:
202                         if (ret == SSH_PROTO_UNKNOWN)
203                                 ret |= SSH_PROTO_1_PREFERRED;
204                         ret |= SSH_PROTO_1;
205                         break;
206                 case 2:
207                         ret |= SSH_PROTO_2;
208                         break;
209                 default:
210                         logit("ignoring bad proto spec: '%s'.", p);
211                         break;
212                 }
213         }
214         xfree(s);
215         return ret;
216 }
217
218 char *
219 compat_cipher_proposal(char *cipher_prop)
220 {
221         Buffer b;
222         char *orig_prop, *fix_ciphers;
223         char *cp, *tmp;
224
225         if (!(datafellows & SSH_BUG_BIGENDIANAES))
226                 return(cipher_prop);
227
228         buffer_init(&b);
229         tmp = orig_prop = xstrdup(cipher_prop);
230         while ((cp = strsep(&tmp, ",")) != NULL) {
231                 if (strncmp(cp, "aes", 3) != 0) {
232                         if (buffer_len(&b) > 0)
233                                 buffer_append(&b, ",", 1);
234                         buffer_append(&b, cp, strlen(cp));
235                 }
236         }
237         buffer_append(&b, "\0", 1);
238         fix_ciphers = xstrdup(buffer_ptr(&b));
239         buffer_free(&b);
240         xfree(orig_prop);
241         debug2("Original cipher proposal: %s", cipher_prop);
242         debug2("Compat cipher proposal: %s", fix_ciphers);
243         if (!*fix_ciphers)
244                 fatal("No available ciphers found.");
245
246         return(fix_ciphers);
247 }