Damien Miller | e3476ed | 2006-07-24 14:13:33 +1000 | [diff] [blame^] | 1 | /* $OpenBSD: match.c,v 1.25 2006/07/22 20:48:23 stevesk 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 | |
| 40 | #include <ctype.h> |
Damien Miller | e3476ed | 2006-07-24 14:13:33 +1000 | [diff] [blame^] | 41 | #include <string.h> |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 42 | |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 43 | #include "match.h" |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 44 | #include "xmalloc.h" |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 45 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 46 | /* |
| 47 | * Returns true if the given string matches the pattern (which may contain ? |
| 48 | * and * as wildcards), and zero if it does not match. |
| 49 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 50 | |
Damien Miller | 4af5130 | 2000-04-16 11:18:38 +1000 | [diff] [blame] | 51 | int |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 52 | match_pattern(const char *s, const char *pattern) |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 53 | { |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 54 | for (;;) { |
| 55 | /* If at end of pattern, accept if also at end of string. */ |
| 56 | if (!*pattern) |
| 57 | return !*s; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 58 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 59 | if (*pattern == '*') { |
| 60 | /* Skip the asterisk. */ |
| 61 | pattern++; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 62 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 63 | /* If at end of pattern, accept immediately. */ |
| 64 | if (!*pattern) |
| 65 | return 1; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 66 | |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 67 | /* If next character in pattern is known, optimize. */ |
| 68 | if (*pattern != '?' && *pattern != '*') { |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 69 | /* |
| 70 | * Look instances of the next character in |
| 71 | * pattern, and try to match starting from |
| 72 | * those. |
| 73 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 74 | for (; *s; s++) |
| 75 | if (*s == *pattern && |
| 76 | match_pattern(s + 1, pattern + 1)) |
| 77 | return 1; |
| 78 | /* Failed. */ |
| 79 | return 0; |
| 80 | } |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 81 | /* |
| 82 | * Move ahead one character at a time and try to |
| 83 | * match at each position. |
| 84 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 85 | for (; *s; s++) |
| 86 | if (match_pattern(s, pattern)) |
| 87 | return 1; |
| 88 | /* Failed. */ |
| 89 | return 0; |
| 90 | } |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 91 | /* |
| 92 | * There must be at least one more character in the string. |
| 93 | * If we are at the end, fail. |
| 94 | */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 95 | if (!*s) |
| 96 | return 0; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 97 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 98 | /* Check if the next character of the string is acceptable. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 99 | if (*pattern != '?' && *pattern != *s) |
| 100 | return 0; |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 101 | |
Damien Miller | 5428f64 | 1999-11-25 11:54:57 +1100 | [diff] [blame] | 102 | /* Move to the next character, both in string and in pattern. */ |
Damien Miller | 95def09 | 1999-11-25 00:26:21 +1100 | [diff] [blame] | 103 | s++; |
| 104 | pattern++; |
| 105 | } |
| 106 | /* NOTREACHED */ |
Damien Miller | d4a8b7e | 1999-10-27 13:42:43 +1000 | [diff] [blame] | 107 | } |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 108 | |
| 109 | /* |
Ben Lindstrom | 9eab262 | 2001-12-06 18:06:05 +0000 | [diff] [blame] | 110 | * Tries to match the string against the |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 111 | * comma-separated sequence of subpatterns (each possibly preceded by ! to |
Damien Miller | d3a1857 | 2000-06-07 19:55:44 +1000 | [diff] [blame] | 112 | * indicate negation). Returns -1 if negation matches, 1 if there is |
| 113 | * a positive match, 0 if there is no match at all. |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 114 | */ |
| 115 | |
| 116 | int |
Ben Lindstrom | 9eab262 | 2001-12-06 18:06:05 +0000 | [diff] [blame] | 117 | match_pattern_list(const char *string, const char *pattern, u_int len, |
| 118 | int dolower) |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 119 | { |
| 120 | char sub[1024]; |
| 121 | int negated; |
| 122 | int got_positive; |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 123 | u_int i, subi; |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 124 | |
| 125 | got_positive = 0; |
| 126 | for (i = 0; i < len;) { |
| 127 | /* Check if the subpattern is negated. */ |
| 128 | if (pattern[i] == '!') { |
| 129 | negated = 1; |
| 130 | i++; |
| 131 | } else |
| 132 | negated = 0; |
| 133 | |
| 134 | /* |
| 135 | * Extract the subpattern up to a comma or end. Convert the |
| 136 | * subpattern to lowercase. |
| 137 | */ |
| 138 | for (subi = 0; |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 139 | i < len && subi < sizeof(sub) - 1 && pattern[i] != ','; |
| 140 | subi++, i++) |
Ben Lindstrom | 9eab262 | 2001-12-06 18:06:05 +0000 | [diff] [blame] | 141 | sub[subi] = dolower && isupper(pattern[i]) ? |
Damien Miller | 1d2b670 | 2006-03-26 14:09:54 +1100 | [diff] [blame] | 142 | (char)tolower(pattern[i]) : pattern[i]; |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 143 | /* If subpattern too long, return failure (no match). */ |
| 144 | if (subi >= sizeof(sub) - 1) |
| 145 | return 0; |
| 146 | |
| 147 | /* If the subpattern was terminated by a comma, skip the comma. */ |
| 148 | if (i < len && pattern[i] == ',') |
| 149 | i++; |
| 150 | |
| 151 | /* Null-terminate the subpattern. */ |
| 152 | sub[subi] = '\0'; |
| 153 | |
Ben Lindstrom | 9eab262 | 2001-12-06 18:06:05 +0000 | [diff] [blame] | 154 | /* Try to match the subpattern against the string. */ |
| 155 | if (match_pattern(string, sub)) { |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 156 | if (negated) |
Damien Miller | d3a1857 | 2000-06-07 19:55:44 +1000 | [diff] [blame] | 157 | return -1; /* Negative */ |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 158 | else |
Damien Miller | d3a1857 | 2000-06-07 19:55:44 +1000 | [diff] [blame] | 159 | got_positive = 1; /* Positive */ |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 160 | } |
| 161 | } |
| 162 | |
| 163 | /* |
| 164 | * Return success if got a positive match. If there was a negative |
Damien Miller | d3a1857 | 2000-06-07 19:55:44 +1000 | [diff] [blame] | 165 | * match, we have already returned -1 and never get here. |
Damien Miller | 450a7a1 | 2000-03-26 13:04:51 +1000 | [diff] [blame] | 166 | */ |
| 167 | return got_positive; |
| 168 | } |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 169 | |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 170 | /* |
Ben Lindstrom | 9eab262 | 2001-12-06 18:06:05 +0000 | [diff] [blame] | 171 | * Tries to match the host name (which must be in all lowercase) against the |
| 172 | * comma-separated sequence of subpatterns (each possibly preceded by ! to |
| 173 | * indicate negation). Returns -1 if negation matches, 1 if there is |
| 174 | * a positive match, 0 if there is no match at all. |
| 175 | */ |
| 176 | int |
| 177 | match_hostname(const char *host, const char *pattern, u_int len) |
| 178 | { |
| 179 | return match_pattern_list(host, pattern, len, 1); |
| 180 | } |
| 181 | |
| 182 | /* |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 183 | * returns 0 if we get a negative match for the hostname or the ip |
| 184 | * or if we get no match at all. returns 1 otherwise. |
| 185 | */ |
| 186 | int |
| 187 | match_host_and_ip(const char *host, const char *ipaddr, |
| 188 | const char *patterns) |
| 189 | { |
| 190 | int mhost, mip; |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 191 | |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 192 | /* negative ipaddr match */ |
| 193 | if ((mip = match_hostname(ipaddr, patterns, strlen(patterns))) == -1) |
| 194 | return 0; |
| 195 | /* negative hostname match */ |
| 196 | if ((mhost = match_hostname(host, patterns, strlen(patterns))) == -1) |
| 197 | return 0; |
| 198 | /* no match at all */ |
| 199 | if (mhost == 0 && mip == 0) |
| 200 | return 0; |
| 201 | return 1; |
| 202 | } |
| 203 | |
| 204 | /* |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 205 | * match user, user@host_or_ip, user@host_or_ip_list against pattern |
| 206 | */ |
| 207 | int |
Ben Lindstrom | 3fb5d00 | 2002-03-05 01:42:42 +0000 | [diff] [blame] | 208 | match_user(const char *user, const char *host, const char *ipaddr, |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 209 | const char *pattern) |
| 210 | { |
| 211 | char *p, *pat; |
| 212 | int ret; |
| 213 | |
| 214 | if ((p = strchr(pattern,'@')) == NULL) |
| 215 | return match_pattern(user, pattern); |
| 216 | |
| 217 | pat = xstrdup(pattern); |
| 218 | p = strchr(pat, '@'); |
| 219 | *p++ = '\0'; |
| 220 | |
| 221 | if ((ret = match_pattern(user, pat)) == 1) |
Ben Lindstrom | 3fb5d00 | 2002-03-05 01:42:42 +0000 | [diff] [blame] | 222 | ret = match_host_and_ip(host, ipaddr, p); |
Ben Lindstrom | 6026002 | 2001-07-04 04:56:44 +0000 | [diff] [blame] | 223 | xfree(pat); |
| 224 | |
| 225 | return ret; |
| 226 | } |
| 227 | |
| 228 | /* |
Ben Lindstrom | f0c5029 | 2001-06-25 05:17:53 +0000 | [diff] [blame] | 229 | * Returns first item from client-list that is also supported by server-list, |
| 230 | * caller must xfree() returned string. |
| 231 | */ |
Damien Miller | afc7a5d | 2002-02-13 13:55:30 +1100 | [diff] [blame] | 232 | #define MAX_PROP 40 |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 233 | #define SEP "," |
| 234 | char * |
| 235 | match_list(const char *client, const char *server, u_int *next) |
| 236 | { |
| 237 | char *sproposals[MAX_PROP]; |
| 238 | char *c, *s, *p, *ret, *cp, *sp; |
| 239 | int i, j, nproposals; |
| 240 | |
| 241 | c = cp = xstrdup(client); |
| 242 | s = sp = xstrdup(server); |
| 243 | |
| 244 | for ((p = strsep(&sp, SEP)), i=0; p && *p != '\0'; |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 245 | (p = strsep(&sp, SEP)), i++) { |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 246 | if (i < MAX_PROP) |
| 247 | sproposals[i] = p; |
| 248 | else |
| 249 | break; |
| 250 | } |
| 251 | nproposals = i; |
| 252 | |
| 253 | for ((p = strsep(&cp, SEP)), i=0; p && *p != '\0'; |
Damien Miller | 9f0f5c6 | 2001-12-21 14:45:46 +1100 | [diff] [blame] | 254 | (p = strsep(&cp, SEP)), i++) { |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 255 | for (j = 0; j < nproposals; j++) { |
| 256 | if (strcmp(p, sproposals[j]) == 0) { |
| 257 | ret = xstrdup(p); |
| 258 | if (next != NULL) |
| 259 | *next = (cp == NULL) ? |
Damien Miller | eccb9de | 2005-06-17 12:59:34 +1000 | [diff] [blame] | 260 | strlen(c) : (u_int)(cp - c); |
Ben Lindstrom | b9be60a | 2001-03-11 01:49:19 +0000 | [diff] [blame] | 261 | xfree(c); |
| 262 | xfree(s); |
| 263 | return ret; |
| 264 | } |
| 265 | } |
| 266 | } |
| 267 | if (next != NULL) |
| 268 | *next = strlen(c); |
| 269 | xfree(c); |
| 270 | xfree(s); |
| 271 | return NULL; |
| 272 | } |