1 /***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 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 https://curl.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 * SPDX-License-Identifier: curl
22 *
23 ***************************************************************************/
24 /* <DESC>
25 * Uses the CURLINFO_TLS_SESSION data.
26 * </DESC>
27 */
28
29 /* Note that this example currently requires curl to be linked against
30 GnuTLS (and this program must also be linked against -lgnutls). */
31
32 #include <stdio.h>
33
34 #include <curl/curl.h>
35 #include <gnutls/gnutls.h>
36 #include <gnutls/x509.h>
37
38 static CURL *curl;
39
wrfu(void * ptr,size_t size,size_t nmemb,void * stream)40 static size_t wrfu(void *ptr, size_t size, size_t nmemb, void *stream)
41 {
42 const struct curl_tlssessioninfo *info;
43 unsigned int cert_list_size;
44 const gnutls_datum_t *chainp;
45 CURLcode res;
46
47 (void)stream;
48 (void)ptr;
49
50 res = CURL_IGNORE_DEPRECATION(
51 curl_easy_getinfo(curl, CURLINFO_TLS_SESSION, &info));
52
53 if(!res) {
54 switch(info->backend) {
55 case CURLSSLBACKEND_GNUTLS:
56 /* info->internals is now the gnutls_session_t */
57 chainp = gnutls_certificate_get_peers(info->internals, &cert_list_size);
58 if((chainp) && (cert_list_size)) {
59 unsigned int i;
60
61 for(i = 0; i < cert_list_size; i++) {
62 gnutls_x509_crt_t cert;
63 gnutls_datum_t dn;
64
65 if(GNUTLS_E_SUCCESS == gnutls_x509_crt_init(&cert)) {
66 if(GNUTLS_E_SUCCESS ==
67 gnutls_x509_crt_import(cert, &chainp[i], GNUTLS_X509_FMT_DER)) {
68 if(GNUTLS_E_SUCCESS ==
69 gnutls_x509_crt_print(cert, GNUTLS_CRT_PRINT_FULL, &dn)) {
70 fprintf(stderr, "Certificate #%u: %.*s", i, dn.size, dn.data);
71
72 gnutls_free(dn.data);
73 }
74 }
75
76 gnutls_x509_crt_deinit(cert);
77 }
78 }
79 }
80 break;
81 case CURLSSLBACKEND_NONE:
82 default:
83 break;
84 }
85 }
86
87 return size * nmemb;
88 }
89
main(void)90 int main(void)
91 {
92 curl_global_init(CURL_GLOBAL_DEFAULT);
93
94 curl = curl_easy_init();
95 if(curl) {
96 curl_easy_setopt(curl, CURLOPT_URL, "https://www.example.com/");
97
98 curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, wrfu);
99
100 curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
101 curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
102
103 curl_easy_setopt(curl, CURLOPT_VERBOSE, 0L);
104
105 (void) curl_easy_perform(curl);
106
107 curl_easy_cleanup(curl);
108 }
109
110 curl_global_cleanup();
111
112 return 0;
113 }
114
