Annotation of src/usr.bin/ssh/compat.c, Revision 1.44
1.5 markus 1: /*
1.23 markus 2: * Copyright (c) 1999,2000 Markus Friedl. All rights reserved.
1.5 markus 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:
1.1 markus 25: #include "includes.h"
1.44 ! markus 26: RCSID("$OpenBSD: compat.c,v 1.43 2001/04/04 15:50:55 markus Exp $");
1.34 markus 27:
28: #include <regex.h>
1.2 markus 29:
1.6 markus 30: #include "packet.h"
1.10 markus 31: #include "xmalloc.h"
32: #include "compat.h"
1.34 markus 33: #include "log.h"
1.1 markus 34:
1.4 markus 35: int compat13 = 0;
1.6 markus 36: int compat20 = 0;
37: int datafellows = 0;
1.4 markus 38:
1.11 markus 39: void
1.6 markus 40: enable_compat20(void)
41: {
1.7 markus 42: verbose("Enabling compatibility mode for protocol 2.0");
43: compat20 = 1;
1.6 markus 44: }
1.11 markus 45: void
1.4 markus 46: enable_compat13(void)
47: {
1.3 markus 48: verbose("Enabling compatibility mode for protocol 1.3");
1.4 markus 49: compat13 = 1;
1.6 markus 50: }
51: /* datafellows bug compatibility */
52: void
53: compat_datafellows(const char *version)
54: {
1.24 markus 55: int i, ret;
56: char ebuf[1024];
57: regex_t reg;
58: static struct {
59: char *pat;
1.13 markus 60: int bugs;
61: } check[] = {
1.33 markus 62: { "^OpenSSH[-_]2\\.[012]",
1.42 provos 63: SSH_OLD_SESSIONID|SSH_BUG_BANNER|
64: SSH_OLD_DHGEX },
65: { "^OpenSSH_2\\.3\\.0", SSH_BUG_BANNER|SSH_BUG_BIGENDIANAES|
66: SSH_OLD_DHGEX},
1.44 ! markus 67: { "^OpenSSH_2\\.3\\.", SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX},
1.40 djm 68: { "^OpenSSH_2\\.5\\.[01]p1",
1.42 provos 69: SSH_BUG_BIGENDIANAES|SSH_OLD_DHGEX },
70: { "^OpenSSH_2\\.5\\.[012]",
71: SSH_OLD_DHGEX },
1.33 markus 72: { "^OpenSSH", 0 },
1.25 markus 73: { "MindTerm", 0 },
1.29 markus 74: { "^2\\.1\\.0", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
1.41 markus 75: SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
76: SSH_BUG_RSASIGMD5 },
1.36 markus 77: { "^2\\.1 ", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
1.41 markus 78: SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
79: SSH_BUG_RSASIGMD5 },
1.28 markus 80: { "^2\\.0\\.1[3-9]", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
1.31 markus 81: SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
1.37 markus 82: SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
1.41 markus 83: SSH_BUG_PKOK|SSH_BUG_RSASIGMD5 },
1.25 markus 84: { "^2\\.0\\.", SSH_BUG_SIGBLOB|SSH_BUG_HMAC|
1.31 markus 85: SSH_OLD_SESSIONID|SSH_BUG_DEBUG|
86: SSH_BUG_PKSERVICE|SSH_BUG_X11FWD|
1.41 markus 87: SSH_BUG_PKAUTH|SSH_BUG_PKOK|
88: SSH_BUG_RSASIGMD5 },
89: { "^2\\.[23]\\.0", SSH_BUG_HMAC|SSH_BUG_RSASIGMD5 },
90: { "^2\\.3\\.", SSH_BUG_RSASIGMD5 },
1.25 markus 91: { "^2\\.[2-9]\\.", 0 },
1.38 deraadt 92: { "^2\\.4$", SSH_OLD_SESSIONID }, /* Van Dyke */
93: { "^3\\.0 SecureCRT", SSH_OLD_SESSIONID },
94: { "^1\\.7 SecureFX", SSH_OLD_SESSIONID },
95: { "^1\\.2\\.1[89]", SSH_BUG_IGNOREMSG },
96: { "^1\\.2\\.2[012]", SSH_BUG_IGNOREMSG },
1.43 markus 97: { "^1\\.3\\.2", SSH_BUG_IGNOREMSG }, /* f-secure */
1.38 deraadt 98: { "^SSH Compatible Server", /* Netscreen */
99: SSH_BUG_PASSWORDPAD },
100: { "^OSU_0", SSH_BUG_PASSWORDPAD },
101: { "^OSU_1\\.[0-4]", SSH_BUG_PASSWORDPAD },
102: { "^OSU_1\\.5alpha[1-3]",
103: SSH_BUG_PASSWORDPAD },
1.39 deraadt 104: { "^SSH_Version_Mapper",
105: SSH_BUG_SCANNER },
1.25 markus 106: { NULL, 0 }
1.6 markus 107: };
1.21 markus 108: /* process table, return first match */
1.24 markus 109: for (i = 0; check[i].pat; i++) {
110: ret = regcomp(®, check[i].pat, REG_EXTENDED|REG_NOSUB);
111: if (ret != 0) {
112: regerror(ret, ®, ebuf, sizeof(ebuf));
113: ebuf[sizeof(ebuf)-1] = '\0';
114: error("regerror: %s", ebuf);
115: continue;
116: }
117: ret = regexec(®, version, 0, NULL, 0);
118: regfree(®);
119: if (ret == 0) {
1.32 provos 120: debug("match: %s pat %s", version, check[i].pat);
1.13 markus 121: datafellows = check[i].bugs;
1.6 markus 122: return;
123: }
124: }
1.24 markus 125: debug("no match: %s", version);
1.10 markus 126: }
127:
128: #define SEP ","
129: int
130: proto_spec(const char *spec)
131: {
1.18 provos 132: char *s, *p, *q;
1.10 markus 133: int ret = SSH_PROTO_UNKNOWN;
134:
1.14 markus 135: if (spec == NULL)
136: return ret;
1.18 provos 137: q = s = xstrdup(spec);
1.19 ho 138: for ((p = strsep(&q, SEP)); p && *p != '\0'; (p = strsep(&q, SEP))) {
1.10 markus 139: switch(atoi(p)) {
140: case 1:
141: if (ret == SSH_PROTO_UNKNOWN)
142: ret |= SSH_PROTO_1_PREFERRED;
143: ret |= SSH_PROTO_1;
144: break;
145: case 2:
146: ret |= SSH_PROTO_2;
147: break;
148: default:
149: log("ignoring bad proto spec: '%s'.", p);
150: break;
151: }
152: }
153: xfree(s);
154: return ret;
1.40 djm 155: }
156:
157: char *
158: compat_cipher_proposal(char *cipher_prop)
159: {
160: char *orig_prop, *fix_ciphers;
161: char *cp, *tmp;
162: size_t len;
163:
164: if (!(datafellows & SSH_BUG_BIGENDIANAES))
165: return(cipher_prop);
166:
167: len = strlen(cipher_prop) + 1;
168: fix_ciphers = xmalloc(len);
169: *fix_ciphers = '\0';
170: tmp = orig_prop = xstrdup(cipher_prop);
171: while((cp = strsep(&tmp, ",")) != NULL) {
172: if (strncmp(cp, "aes", 3) && strncmp(cp, "rijndael", 8)) {
173: if (*fix_ciphers)
174: strlcat(fix_ciphers, ",", len);
175: strlcat(fix_ciphers, cp, len);
176: }
177: }
178: xfree(orig_prop);
179: debug2("Original cipher proposal: %s", cipher_prop);
180: debug2("Compat cipher proposal: %s", fix_ciphers);
181: if (!*fix_ciphers)
182: fatal("No available ciphers found.");
183:
184: return(fix_ciphers);
1.1 markus 185: }