1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2015, Daniel Stenberg, <daniel@haxx.se>, et al.
9 *
10 * This software is licensed as described in the file COPYING, which
11 * you should have received as part of this distribution. The terms
12 * are also available at http://curl.haxx.se/docs/copyright.html.
13 *
14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell
15 * copies of the Software, and permit persons to whom the Software is
16 * furnished to do so, under the terms of the COPYING file.
17 *
18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
19 * KIND, either express or implied.
20 *
21 ***************************************************************************/
22
23 #include "curl_setup.h"
24
25 #if defined(USE_OPENSSL) || defined(USE_AXTLS) || defined(USE_GSKIT)
26 /* these backends use functions from this file */
27
28 #ifdef HAVE_NETINET_IN_H
29 #include <netinet/in.h>
30 #endif
31
32 #include "hostcheck.h"
33 #include "rawstr.h"
34 #include "inet_pton.h"
35
36 #include "curl_memory.h"
37 /* The last #include file should be: */
38 #include "memdebug.h"
39
40 /*
41 * Match a hostname against a wildcard pattern.
42 * E.g.
43 * "foo.host.com" matches "*.host.com".
44 *
45 * We use the matching rule described in RFC6125, section 6.4.3.
46 * http://tools.ietf.org/html/rfc6125#section-6.4.3
47 *
48 * In addition: ignore trailing dots in the host names and wildcards, so that
49 * the names are used normalized. This is what the browsers do.
50 *
51 * Do not allow wildcard matching on IP numbers. There are apparently
52 * certificates being used with an IP address in the CN field, thus making no
53 * apparent distinction between a name and an IP. We need to detect the use of
54 * an IP address and not wildcard match on such names.
55 *
56 * NOTE: hostmatch() gets called with copied buffers so that it can modify the
57 * contents at will.
58 */
59
hostmatch(char * hostname,char * pattern)60 static int hostmatch(char *hostname, char *pattern)
61 {
62 const char *pattern_label_end, *pattern_wildcard, *hostname_label_end;
63 int wildcard_enabled;
64 size_t prefixlen, suffixlen;
65 struct in_addr ignored;
66 #ifdef ENABLE_IPV6
67 struct sockaddr_in6 si6;
68 #endif
69
70 /* normalize pattern and hostname by stripping off trailing dots */
71 size_t len = strlen(hostname);
72 if(hostname[len-1]=='.')
73 hostname[len-1]=0;
74 len = strlen(pattern);
75 if(pattern[len-1]=='.')
76 pattern[len-1]=0;
77
78 pattern_wildcard = strchr(pattern, '*');
79 if(pattern_wildcard == NULL)
80 return Curl_raw_equal(pattern, hostname) ?
81 CURL_HOST_MATCH : CURL_HOST_NOMATCH;
82
83 /* detect IP address as hostname and fail the match if so */
84 if(Curl_inet_pton(AF_INET, hostname, &ignored) > 0)
85 return CURL_HOST_NOMATCH;
86 #ifdef ENABLE_IPV6
87 else if(Curl_inet_pton(AF_INET6, hostname, &si6.sin6_addr) > 0)
88 return CURL_HOST_NOMATCH;
89 #endif
90
91 /* We require at least 2 dots in pattern to avoid too wide wildcard
92 match. */
93 wildcard_enabled = 1;
94 pattern_label_end = strchr(pattern, '.');
95 if(pattern_label_end == NULL || strchr(pattern_label_end+1, '.') == NULL ||
96 pattern_wildcard > pattern_label_end ||
97 Curl_raw_nequal(pattern, "xn--", 4)) {
98 wildcard_enabled = 0;
99 }
100 if(!wildcard_enabled)
101 return Curl_raw_equal(pattern, hostname) ?
102 CURL_HOST_MATCH : CURL_HOST_NOMATCH;
103
104 hostname_label_end = strchr(hostname, '.');
105 if(hostname_label_end == NULL ||
106 !Curl_raw_equal(pattern_label_end, hostname_label_end))
107 return CURL_HOST_NOMATCH;
108
109 /* The wildcard must match at least one character, so the left-most
110 label of the hostname is at least as large as the left-most label
111 of the pattern. */
112 if(hostname_label_end - hostname < pattern_label_end - pattern)
113 return CURL_HOST_NOMATCH;
114
115 prefixlen = pattern_wildcard - pattern;
116 suffixlen = pattern_label_end - (pattern_wildcard+1);
117 return Curl_raw_nequal(pattern, hostname, prefixlen) &&
118 Curl_raw_nequal(pattern_wildcard+1, hostname_label_end - suffixlen,
119 suffixlen) ?
120 CURL_HOST_MATCH : CURL_HOST_NOMATCH;
121 }
122
Curl_cert_hostcheck(const char * match_pattern,const char * hostname)123 int Curl_cert_hostcheck(const char *match_pattern, const char *hostname)
124 {
125 char *matchp;
126 char *hostp;
127 int res = 0;
128 if(!match_pattern || !*match_pattern ||
129 !hostname || !*hostname) /* sanity check */
130 ;
131 else {
132 matchp = strdup(match_pattern);
133 if(matchp) {
134 hostp = strdup(hostname);
135 if(hostp) {
136 if(hostmatch(hostp, matchp) == CURL_HOST_MATCH)
137 res= 1;
138 free(hostp);
139 }
140 free(matchp);
141 }
142 }
143
144 return res;
145 }
146
147 #endif /* OPENSSL or AXTLS or GSKIT */
148