/*
- *
- * match.c
- *
* Author: Tatu Ylonen <ylo@cs.hut.fi>
- *
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
- *
- * Created: Thu Jun 22 01:17:50 1995 ylo
- *
* Simple pattern matching, with '*' and '?' as wildcards.
- *
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose. Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
*/
#include "includes.h"
-RCSID("$Id$");
+RCSID("$OpenBSD: match.c,v 1.9 2000/09/07 20:27:52 deraadt Exp $");
#include "ssh.h"
-/* Returns true if the given string matches the pattern (which may contain
- ? and * as wildcards), and zero if it does not match. */
+/*
+ * Returns true if the given string matches the pattern (which may contain ?
+ * and * as wildcards), and zero if it does not match.
+ */
-int
+int
match_pattern(const char *s, const char *pattern)
{
for (;;) {
if (!*pattern)
return !*s;
- /* Process '*'. */
if (*pattern == '*') {
/* Skip the asterisk. */
pattern++;
/* If next character in pattern is known, optimize. */
if (*pattern != '?' && *pattern != '*') {
- /* Look instances of the next character in
- pattern, and try to match starting from
- those. */
+ /*
+ * Look instances of the next character in
+ * pattern, and try to match starting from
+ * those.
+ */
for (; *s; s++)
if (*s == *pattern &&
match_pattern(s + 1, pattern + 1))
/* Failed. */
return 0;
}
- /* Move ahead one character at a time and try to
- match at each position. */
+ /*
+ * Move ahead one character at a time and try to
+ * match at each position.
+ */
for (; *s; s++)
if (match_pattern(s, pattern))
return 1;
/* Failed. */
return 0;
}
- /* There must be at least one more character in the
- string. If we are at the end, fail. */
+ /*
+ * There must be at least one more character in the string.
+ * If we are at the end, fail.
+ */
if (!*s)
return 0;
- /* Check if the next character of the string is
- acceptable. */
+ /* Check if the next character of the string is acceptable. */
if (*pattern != '?' && *pattern != *s)
return 0;
- /* Move to the next character, both in string and in
- pattern. */
+ /* Move to the next character, both in string and in pattern. */
s++;
pattern++;
}
/* NOTREACHED */
}
+
+/*
+ * Tries to match the host name (which must be in all lowercase) against the
+ * comma-separated sequence of subpatterns (each possibly preceded by ! to
+ * indicate negation). Returns -1 if negation matches, 1 if there is
+ * a positive match, 0 if there is no match at all.
+ */
+
+int
+match_hostname(const char *host, const char *pattern, unsigned int len)
+{
+ char sub[1024];
+ int negated;
+ int got_positive;
+ unsigned int i, subi;
+
+ got_positive = 0;
+ for (i = 0; i < len;) {
+ /* Check if the subpattern is negated. */
+ if (pattern[i] == '!') {
+ negated = 1;
+ i++;
+ } else
+ negated = 0;
+
+ /*
+ * Extract the subpattern up to a comma or end. Convert the
+ * subpattern to lowercase.
+ */
+ for (subi = 0;
+ i < len && subi < sizeof(sub) - 1 && pattern[i] != ',';
+ subi++, i++)
+ sub[subi] = isupper(pattern[i]) ? tolower(pattern[i]) : pattern[i];
+ /* If subpattern too long, return failure (no match). */
+ if (subi >= sizeof(sub) - 1)
+ return 0;
+
+ /* If the subpattern was terminated by a comma, skip the comma. */
+ if (i < len && pattern[i] == ',')
+ i++;
+
+ /* Null-terminate the subpattern. */
+ sub[subi] = '\0';
+
+ /* Try to match the subpattern against the host name. */
+ if (match_pattern(host, sub)) {
+ if (negated)
+ return -1; /* Negative */
+ else
+ got_positive = 1; /* Positive */
+ }
+ }
+
+ /*
+ * Return success if got a positive match. If there was a negative
+ * match, we have already returned -1 and never get here.
+ */
+ return got_positive;
+}