1 /*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel (at) 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 https://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) \ 26 || defined(USE_AXTLS) \ 27 || defined(USE_GSKIT) \ 28 || (defined(USE_SCHANNEL) && defined(_WIN32_WCE)) 29 /* these backends use functions from this file */ 30 31 #ifdef HAVE_NETINET_IN_H 32 #include <netinet/in.h> 33 #endif 34 #ifdef HAVE_NETINET_IN6_H 35 #include <netinet/in6.h> 36 #endif 37 38 #include "hostcheck.h" 39 #include "strcase.h" 40 #include "inet_pton.h" 41 42 #include "curl_memory.h" 43 /* The last #include file should be: */ 44 #include "memdebug.h" 45 46 /* 47 * Match a hostname against a wildcard pattern. 48 * E.g. 49 * "foo.host.com" matches "*.host.com". 50 * 51 * We use the matching rule described in RFC6125, section 6.4.3. 52 * https://tools.ietf.org/html/rfc6125#section-6.4.3 53 * 54 * In addition: ignore trailing dots in the host names and wildcards, so that 55 * the names are used normalized. This is what the browsers do. 56 * 57 * Do not allow wildcard matching on IP numbers. There are apparently 58 * certificates being used with an IP address in the CN field, thus making no 59 * apparent distinction between a name and an IP. We need to detect the use of 60 * an IP address and not wildcard match on such names. 61 * 62 * NOTE: hostmatch() gets called with copied buffers so that it can modify the 63 * contents at will. 64 */ 65 66 static int hostmatch(char *hostname, char *pattern) 67 { 68 const char *pattern_label_end, *pattern_wildcard, *hostname_label_end; 69 int wildcard_enabled; 70 size_t prefixlen, suffixlen; 71 struct in_addr ignored; 72 #ifdef ENABLE_IPV6 73 struct sockaddr_in6 si6; 74 #endif 75 76 /* normalize pattern and hostname by stripping off trailing dots */ 77 size_t len = strlen(hostname); 78 if(hostname[len-1]=='.') 79 hostname[len-1] = 0; 80 len = strlen(pattern); 81 if(pattern[len-1]=='.') 82 pattern[len-1] = 0; 83 84 pattern_wildcard = strchr(pattern, '*'); 85 if(pattern_wildcard == NULL) 86 return strcasecompare(pattern, hostname) ? 87 CURL_HOST_MATCH : CURL_HOST_NOMATCH; 88 89 /* detect IP address as hostname and fail the match if so */ 90 if(Curl_inet_pton(AF_INET, hostname, &ignored) > 0) 91 return CURL_HOST_NOMATCH; 92 #ifdef ENABLE_IPV6 93 if(Curl_inet_pton(AF_INET6, hostname, &si6.sin6_addr) > 0) 94 return CURL_HOST_NOMATCH; 95 #endif 96 97 /* We require at least 2 dots in pattern to avoid too wide wildcard 98 match. */ 99 wildcard_enabled = 1; 100 pattern_label_end = strchr(pattern, '.'); 101 if(pattern_label_end == NULL || strchr(pattern_label_end + 1, '.') == NULL || 102 pattern_wildcard > pattern_label_end || 103 strncasecompare(pattern, "xn--", 4)) { 104 wildcard_enabled = 0; 105 } 106 if(!wildcard_enabled) 107 return strcasecompare(pattern, hostname) ? 108 CURL_HOST_MATCH : CURL_HOST_NOMATCH; 109 110 hostname_label_end = strchr(hostname, '.'); 111 if(hostname_label_end == NULL || 112 !strcasecompare(pattern_label_end, hostname_label_end)) 113 return CURL_HOST_NOMATCH; 114 115 /* The wildcard must match at least one character, so the left-most 116 label of the hostname is at least as large as the left-most label 117 of the pattern. */ 118 if(hostname_label_end - hostname < pattern_label_end - pattern) 119 return CURL_HOST_NOMATCH; 120 121 prefixlen = pattern_wildcard - pattern; 122 suffixlen = pattern_label_end - (pattern_wildcard + 1); 123 return strncasecompare(pattern, hostname, prefixlen) && 124 strncasecompare(pattern_wildcard + 1, hostname_label_end - suffixlen, 125 suffixlen) ? 126 CURL_HOST_MATCH : CURL_HOST_NOMATCH; 127 } 128 129 int Curl_cert_hostcheck(const char *match_pattern, const char *hostname) 130 { 131 char *matchp; 132 char *hostp; 133 int res = 0; 134 if(!match_pattern || !*match_pattern || 135 !hostname || !*hostname) /* sanity check */ 136 ; 137 else { 138 matchp = strdup(match_pattern); 139 if(matchp) { 140 hostp = strdup(hostname); 141 if(hostp) { 142 if(hostmatch(hostp, matchp) == CURL_HOST_MATCH) 143 res = 1; 144 free(hostp); 145 } 146 free(matchp); 147 } 148 } 149 150 return res; 151 } 152 153 #endif /* OPENSSL, AXTLS, GSKIT or schannel+wince */ 154
