djm@openbsd.org | 010359b | 2016-11-06 05:46:37 +0000 | [diff] [blame] | 1 | /* $OpenBSD: match.c,v 1.33 2016/11/06 05:46:37 djm Exp $ */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 2 | /* |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 3 | * Author: Tatu Ylonen <ylo@cs.hut.fi> |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 4 | * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland |
| 5 | * All rights reserved |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 6 | * Simple pattern matching, with '*' and '?' as wildcards. |
Damien Miller | 4af5130 | 2000-04-16 11:18:38 +1000 | [diff] [blame] | 7 | * |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 8 | * As far as I am concerned, the code I have written for this software |
| 9 | * can be used freely for any purpose. Any derived versions of this |
| 10 | * software must be clearly marked as such, and if the derived work is |
| 11 | * incompatible with the protocol description in the RFC file, it must be |
| 12 | * called by a name other than "ssh" or "Secure Shell". |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 13 | */ |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 14 | /* |
| 15 | * Copyright (c) 2000 Markus Friedl. All rights reserved. |
| 16 | * |
| 17 | * Redistribution and use in source and binary forms, with or without |
| 18 | * modification, are permitted provided that the following conditions |
| 19 | * are met: |
| 20 | * 1. Redistributions of source code must retain the above copyright |
| 21 | * notice, this list of conditions and the following disclaimer. |
| 22 | * 2. Redistributions in binary form must reproduce the above copyright |
| 23 | * notice, this list of conditions and the following disclaimer in the |
| 24 | * documentation and/or other materials provided with the distribution. |
| 25 | * |
| 26 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 27 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 28 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 29 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 30 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 31 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 32 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 33 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 34 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 35 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 36 | */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 37 | |
| 38 | #include "includes.h" |
Damien Miller | c7b0636 | 2006-03-15 11:53:45 +1100 | [diff] [blame] | 39 | |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 40 | #include <sys/types.h> |
| 41 | |
Damien Miller | c7b0636 | 2006-03-15 11:53:45 +1100 | [diff] [blame] | 42 | #include <ctype.h> |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 43 | #include <stdlib.h> |
Damien Miller | e3476ed | 2006-07-24 14:13:33 +1000 | [diff] [blame] | 44 | #include <string.h> |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 45 | |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 46 | #include "xmalloc.h" |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 47 | #include "match.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 48 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 49 | /* |
| 50 | * Returns true if the given string matches the pattern (which may contain ? |
| 51 | * and * as wildcards), and zero if it does not match. |
| 52 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 53 | |
Damien Miller | 4af5130 | 2000-04-16 11:18:38 +1000 | [diff] [blame] | 54 | int |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 55 | match_pattern(const char *s, const char *pattern) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 56 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 57 | for (;;) { |
| 58 | /* If at end of pattern, accept if also at end of string. */ |
| 59 | if (!*pattern) |
| 60 | return !*s; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 61 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 62 | if (*pattern == '*') { |
| 63 | /* Skip the asterisk. */ |
| 64 | pattern++; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 65 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 66 | /* If at end of pattern, accept immediately. */ |
| 67 | if (!*pattern) |
| 68 | return 1; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 69 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 70 | /* If next character in pattern is known, optimize. */ |
| 71 | if (*pattern != '?' && *pattern != '*') { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 72 | /* |
| 73 | * Look instances of the next character in |
| 74 | * pattern, and try to match starting from |
| 75 | * those. |
| 76 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 77 | for (; *s; s++) |
| 78 | if (*s == *pattern && |
| 79 | match_pattern(s + 1, pattern + 1)) |
| 80 | return 1; |
| 81 | /* Failed. */ |
| 82 | return 0; |
| 83 | } |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 84 | /* |
| 85 | * Move ahead one character at a time and try to |
| 86 | * match at each position. |
| 87 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 88 | for (; *s; s++) |
| 89 | if (match_pattern(s, pattern)) |
| 90 | return 1; |
| 91 | /* Failed. */ |
| 92 | return 0; |
| 93 | } |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 94 | /* |
| 95 | * There must be at least one more character in the string. |
| 96 | * If we are at the end, fail. |
| 97 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 98 | if (!*s) |
| 99 | return 0; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 100 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 101 | /* Check if the next character of the string is acceptable. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 102 | if (*pattern != '?' && *pattern != *s) |
| 103 | return 0; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 104 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 105 | /* Move to the next character, both in string and in pattern. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 106 | s++; |
| 107 | pattern++; |
| 108 | } |
| 109 | /* NOTREACHED */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 110 | } |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 111 | |
| 112 | /* |
Ben Lindstrom | 9eab262 | 2001-12-06 18:06:05 +0000 | [diff] [blame] | 113 | * Tries to match the string against the |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 114 | * comma-separated sequence of subpatterns (each possibly preceded by ! to |
Damien Miller | d3a1857 | 2000-06-07 19:55:44 +1000 | [diff] [blame] | 115 | * indicate negation). Returns -1 if negation matches, 1 if there is |
| 116 | * a positive match, 0 if there is no match at all. |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 117 | */ |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 118 | int |
djm@openbsd.org | e661a86 | 2015-05-04 06:10:48 +0000 | [diff] [blame] | 119 | match_pattern_list(const char *string, const char *pattern, int dolower) |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 120 | { |
| 121 | char sub[1024]; |
| 122 | int negated; |
| 123 | int got_positive; |
djm@openbsd.org | e661a86 | 2015-05-04 06:10:48 +0000 | [diff] [blame] | 124 | u_int i, subi, len = strlen(pattern); |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 125 | |
| 126 | got_positive = 0; |
| 127 | for (i = 0; i < len;) { |
| 128 | /* Check if the subpattern is negated. */ |
| 129 | if (pattern[i] == '!') { |
| 130 | negated = 1; |
| 131 | i++; |
| 132 | } else |
| 133 | negated = 0; |
| 134 | |
| 135 | /* |
| 136 | * Extract the subpattern up to a comma or end. Convert the |
| 137 | * subpattern to lowercase. |
| 138 | */ |
| 139 | for (subi = 0; |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 140 | i < len && subi < sizeof(sub) - 1 && pattern[i] != ','; |
| 141 | subi++, i++) |
Damien Miller | fdb2306 | 2013-11-21 13:57:15 +1100 | [diff] [blame] | 142 | sub[subi] = dolower && isupper((u_char)pattern[i]) ? |
| 143 | tolower((u_char)pattern[i]) : pattern[i]; |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 144 | /* If subpattern too long, return failure (no match). */ |
| 145 | if (subi >= sizeof(sub) - 1) |
| 146 | return 0; |
| 147 | |
| 148 | /* If the subpattern was terminated by a comma, skip the comma. */ |
| 149 | if (i < len && pattern[i] == ',') |
| 150 | i++; |
| 151 | |
| 152 | /* Null-terminate the subpattern. */ |
| 153 | sub[subi] = '\0'; |
| 154 | |
Ben Lindstrom | 9eab262 | 2001-12-06 18:06:05 +0000 | [diff] [blame] | 155 | /* Try to match the subpattern against the string. */ |
| 156 | if (match_pattern(string, sub)) { |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 157 | if (negated) |
Damien Miller | d3a1857 | 2000-06-07 19:55:44 +1000 | [diff] [blame] | 158 | return -1; /* Negative */ |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 159 | else |
Damien Miller | d3a1857 | 2000-06-07 19:55:44 +1000 | [diff] [blame] | 160 | got_positive = 1; /* Positive */ |
djm@openbsd.org | a5ad3a9 | 2016-09-21 16:55:42 +0000 | [diff] [blame] | 161 | } |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 162 | } |
| 163 | |
| 164 | /* |
| 165 | * Return success if got a positive match. If there was a negative |
Damien Miller | d3a1857 | 2000-06-07 19:55:44 +1000 | [diff] [blame] | 166 | * match, we have already returned -1 and never get here. |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 167 | */ |
| 168 | return got_positive; |
| 169 | } |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 170 | |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 171 | /* |
Ben Lindstrom | 9eab262 | 2001-12-06 18:06:05 +0000 | [diff] [blame] | 172 | * Tries to match the host name (which must be in all lowercase) against the |
| 173 | * comma-separated sequence of subpatterns (each possibly preceded by ! to |
| 174 | * indicate negation). Returns -1 if negation matches, 1 if there is |
| 175 | * a positive match, 0 if there is no match at all. |
| 176 | */ |
| 177 | int |
djm@openbsd.org | e661a86 | 2015-05-04 06:10:48 +0000 | [diff] [blame] | 178 | match_hostname(const char *host, const char *pattern) |
Ben Lindstrom | 9eab262 | 2001-12-06 18:06:05 +0000 | [diff] [blame] | 179 | { |
djm@openbsd.org | e661a86 | 2015-05-04 06:10:48 +0000 | [diff] [blame] | 180 | return match_pattern_list(host, pattern, 1); |
Ben Lindstrom | 9eab262 | 2001-12-06 18:06:05 +0000 | [diff] [blame] | 181 | } |
| 182 | |
| 183 | /* |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 184 | * returns 0 if we get a negative match for the hostname or the ip |
Darren Tucker | 896ad5a | 2008-06-11 09:34:46 +1000 | [diff] [blame] | 185 | * or if we get no match at all. returns -1 on error, or 1 on |
| 186 | * successful match. |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 187 | */ |
| 188 | int |
| 189 | match_host_and_ip(const char *host, const char *ipaddr, |
| 190 | const char *patterns) |
| 191 | { |
| 192 | int mhost, mip; |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 193 | |
Darren Tucker | 896ad5a | 2008-06-11 09:34:46 +1000 | [diff] [blame] | 194 | if ((mip = addr_match_list(ipaddr, patterns)) == -2) |
djm@openbsd.org | 010359b | 2016-11-06 05:46:37 +0000 | [diff] [blame] | 195 | return -1; /* error in ipaddr match */ |
| 196 | else if (host == NULL || ipaddr == NULL || mip == -1) |
| 197 | return 0; /* negative ip address match, or testing pattern */ |
Darren Tucker | 896ad5a | 2008-06-11 09:34:46 +1000 | [diff] [blame] | 198 | |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 199 | /* negative hostname match */ |
djm@openbsd.org | e661a86 | 2015-05-04 06:10:48 +0000 | [diff] [blame] | 200 | if ((mhost = match_hostname(host, patterns)) == -1) |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 201 | return 0; |
| 202 | /* no match at all */ |
| 203 | if (mhost == 0 && mip == 0) |
| 204 | return 0; |
| 205 | return 1; |
| 206 | } |
| 207 | |
| 208 | /* |
djm@openbsd.org | 010359b | 2016-11-06 05:46:37 +0000 | [diff] [blame] | 209 | * Match user, user@host_or_ip, user@host_or_ip_list against pattern. |
| 210 | * If user, host and ipaddr are all NULL then validate pattern/ |
| 211 | * Returns -1 on invalid pattern, 0 on no match, 1 on match. |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 212 | */ |
| 213 | int |
Ben Lindstrom | 3fb5d00 | 2002-03-05 01:42:42 +0000 | [diff] [blame] | 214 | match_user(const char *user, const char *host, const char *ipaddr, |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 215 | const char *pattern) |
| 216 | { |
| 217 | char *p, *pat; |
| 218 | int ret; |
| 219 | |
djm@openbsd.org | 010359b | 2016-11-06 05:46:37 +0000 | [diff] [blame] | 220 | /* test mode */ |
| 221 | if (user == NULL && host == NULL && ipaddr == NULL) { |
| 222 | if ((p = strchr(pattern, '@')) != NULL && |
| 223 | match_host_and_ip(NULL, NULL, p + 1) < 0) |
| 224 | return -1; |
| 225 | return 0; |
| 226 | } |
| 227 | |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 228 | if ((p = strchr(pattern,'@')) == NULL) |
| 229 | return match_pattern(user, pattern); |
| 230 | |
| 231 | pat = xstrdup(pattern); |
| 232 | p = strchr(pat, '@'); |
| 233 | *p++ = '\0'; |
| 234 | |
| 235 | if ((ret = match_pattern(user, pat)) == 1) |
Ben Lindstrom | 3fb5d00 | 2002-03-05 01:42:42 +0000 | [diff] [blame] | 236 | ret = match_host_and_ip(host, ipaddr, p); |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 237 | free(pat); |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 238 | |
| 239 | return ret; |
| 240 | } |
| 241 | |
| 242 | /* |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 243 | * Returns first item from client-list that is also supported by server-list, |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 244 | * caller must free the returned string. |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 245 | */ |
Damien Miller | afc7a5d | 2002-02-13 13:55:30 +1100 | [diff] [blame] | 246 | #define MAX_PROP 40 |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 247 | #define SEP "," |
| 248 | char * |
| 249 | match_list(const char *client, const char *server, u_int *next) |
| 250 | { |
| 251 | char *sproposals[MAX_PROP]; |
| 252 | char *c, *s, *p, *ret, *cp, *sp; |
| 253 | int i, j, nproposals; |
| 254 | |
| 255 | c = cp = xstrdup(client); |
| 256 | s = sp = xstrdup(server); |
| 257 | |
| 258 | for ((p = strsep(&sp, SEP)), i=0; p && *p != '\0'; |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 259 | (p = strsep(&sp, SEP)), i++) { |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 260 | if (i < MAX_PROP) |
| 261 | sproposals[i] = p; |
| 262 | else |
| 263 | break; |
| 264 | } |
| 265 | nproposals = i; |
| 266 | |
| 267 | for ((p = strsep(&cp, SEP)), i=0; p && *p != '\0'; |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 268 | (p = strsep(&cp, SEP)), i++) { |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 269 | for (j = 0; j < nproposals; j++) { |
| 270 | if (strcmp(p, sproposals[j]) == 0) { |
| 271 | ret = xstrdup(p); |
| 272 | if (next != NULL) |
| 273 | *next = (cp == NULL) ? |
Damien Miller | eccb9de | 2005-06-17 12:59:34 +1000 | [diff] [blame] | 274 | strlen(c) : (u_int)(cp - c); |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 275 | free(c); |
| 276 | free(s); |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 277 | return ret; |
| 278 | } |
| 279 | } |
| 280 | } |
| 281 | if (next != NULL) |
| 282 | *next = strlen(c); |
Darren Tucker | a627d42 | 2013-06-02 07:31:17 +1000 | [diff] [blame] | 283 | free(c); |
| 284 | free(s); |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 285 | return NULL; |
| 286 | } |