2 * Author: Tatu Ylonen <ylo@cs.hut.fi>
3 * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
5 * Simple pattern matching, with '*' and '?' as wildcards.
7 * As far as I am concerned, the code I have written for this software
8 * can be used freely for any purpose. Any derived versions of this
9 * software must be clearly marked as such, and if the derived work is
10 * incompatible with the protocol description in the RFC file, it must be
11 * called by a name other than "ssh" or "Secure Shell".
14 * Copyright (c) 2000 Markus Friedl. All rights reserved.
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
19 * 1. Redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution.
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
45 * Returns true if the given string matches the pattern (which may contain ?
46 * and * as wildcards), and zero if it does not match.
50 match_pattern(const char *s, const char *pattern)
53 /* If at end of pattern, accept if also at end of string. */
57 if (*pattern == '*') {
58 /* Skip the asterisk. */
61 /* If at end of pattern, accept immediately. */
65 /* If next character in pattern is known, optimize. */
66 if (*pattern != '?' && *pattern != '*') {
68 * Look instances of the next character in
69 * pattern, and try to match starting from
74 match_pattern(s + 1, pattern + 1))
80 * Move ahead one character at a time and try to
81 * match at each position.
84 if (match_pattern(s, pattern))
90 * There must be at least one more character in the string.
91 * If we are at the end, fail.
96 /* Check if the next character of the string is acceptable. */
97 if (*pattern != '?' && *pattern != *s)
100 /* Move to the next character, both in string and in pattern. */
108 * Tries to match the string against the
109 * comma-separated sequence of subpatterns (each possibly preceded by ! to
110 * indicate negation). Returns -1 if negation matches, 1 if there is
111 * a positive match, 0 if there is no match at all.
115 match_pattern_list(const char *string, const char *pattern, u_int len,
124 for (i = 0; i < len;) {
125 /* Check if the subpattern is negated. */
126 if (pattern[i] == '!') {
133 * Extract the subpattern up to a comma or end. Convert the
134 * subpattern to lowercase.
137 i < len && subi < sizeof(sub) - 1 && pattern[i] != ',';
139 sub[subi] = dolower && isupper(pattern[i]) ?
140 tolower(pattern[i]) : pattern[i];
141 /* If subpattern too long, return failure (no match). */
142 if (subi >= sizeof(sub) - 1)
145 /* If the subpattern was terminated by a comma, skip the comma. */
146 if (i < len && pattern[i] == ',')
149 /* Null-terminate the subpattern. */
152 /* Try to match the subpattern against the string. */
153 if (match_pattern(string, sub)) {
155 return -1; /* Negative */
157 got_positive = 1; /* Positive */
162 * Return success if got a positive match. If there was a negative
163 * match, we have already returned -1 and never get here.
169 * Tries to match the host name (which must be in all lowercase) against the
170 * comma-separated sequence of subpatterns (each possibly preceded by ! to
171 * indicate negation). Returns -1 if negation matches, 1 if there is
172 * a positive match, 0 if there is no match at all.
175 match_hostname(const char *host, const char *pattern, u_int len)
177 return match_pattern_list(host, pattern, len, 1);
181 * returns 0 if we get a negative match for the hostname or the ip
182 * or if we get no match at all. returns 1 otherwise.
185 match_host_and_ip(const char *host, const char *ipaddr,
186 const char *patterns)
190 /* negative ipaddr match */
191 if ((mip = match_hostname(ipaddr, patterns, strlen(patterns))) == -1)
193 /* negative hostname match */
194 if ((mhost = match_hostname(host, patterns, strlen(patterns))) == -1)
196 /* no match at all */
197 if (mhost == 0 && mip == 0)
203 * match user, user@host_or_ip, user@host_or_ip_list against pattern
206 match_user(const char *user, const char *host, const char *ipaddr,
212 if ((p = strchr(pattern,'@')) == NULL)
213 return match_pattern(user, pattern);
215 pat = xstrdup(pattern);
216 p = strchr(pat, '@');
219 if ((ret = match_pattern(user, pat)) == 1)
220 ret = match_host_and_ip(host, ipaddr, p);
227 * Returns first item from client-list that is also supported by server-list,
228 * caller must xfree() returned string.
233 match_list(const char *client, const char *server, u_int *next)
235 char *sproposals[MAX_PROP];
236 char *c, *s, *p, *ret, *cp, *sp;
237 int i, j, nproposals;
239 c = cp = xstrdup(client);
240 s = sp = xstrdup(server);
242 for ((p = strsep(&sp, SEP)), i=0; p && *p != '\0';
243 (p = strsep(&sp, SEP)), i++) {
251 for ((p = strsep(&cp, SEP)), i=0; p && *p != '\0';
252 (p = strsep(&cp, SEP)), i++) {
253 for (j = 0; j < nproposals; j++) {
254 if (strcmp(p, sproposals[j]) == 0) {
257 *next = (cp == NULL) ?
258 strlen(c) : (u_int)(cp - c);