xref: /third_party/curl/docs/examples/pop3-ssl.c (revision 13498266)
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
25/* <DESC>
26 * Get POP3 email using implicit SSL
27 * </DESC>
28 */
29
30#include <stdio.h>
31#include <curl/curl.h>
32
33/* This is a simple example showing how to retrieve mail using libcurl's POP3
34 * capabilities. It builds on the pop3-retr.c example adding transport
35 * security to protect the authentication details from being snooped.
36 *
37 * Note that this example requires libcurl 7.20.0 or above.
38 */
39
40int main(void)
41{
42  CURL *curl;
43  CURLcode res = CURLE_OK;
44
45  curl = curl_easy_init();
46  if(curl) {
47    /* Set username and password */
48    curl_easy_setopt(curl, CURLOPT_USERNAME, "user");
49    curl_easy_setopt(curl, CURLOPT_PASSWORD, "secret");
50
51    /* This will retrieve message 1 from the user's mailbox. Note the use of
52     * pop3s:// rather than pop3:// to request a SSL based connection. */
53    curl_easy_setopt(curl, CURLOPT_URL, "pop3s://pop.example.com/1");
54
55    /* If you want to connect to a site who is not using a certificate that is
56     * signed by one of the certs in the CA bundle you have, you can skip the
57     * verification of the server's certificate. This makes the connection
58     * A LOT LESS SECURE.
59     *
60     * If you have a CA cert for the server stored someplace else than in the
61     * default bundle, then the CURLOPT_CAPATH option might come handy for
62     * you. */
63#ifdef SKIP_PEER_VERIFICATION
64    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
65#endif
66
67    /* If the site you are connecting to uses a different host name that what
68     * they have mentioned in their server certificate's commonName (or
69     * subjectAltName) fields, libcurl will refuse to connect. You can skip
70     * this check, but this will make the connection less secure. */
71#ifdef SKIP_HOSTNAME_VERIFICATION
72    curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
73#endif
74
75    /* Since the traffic will be encrypted, it is useful to turn on debug
76     * information within libcurl to see what is happening during the
77     * transfer */
78    curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
79
80    /* Perform the retr */
81    res = curl_easy_perform(curl);
82
83    /* Check for errors */
84    if(res != CURLE_OK)
85      fprintf(stderr, "curl_easy_perform() failed: %s\n",
86              curl_easy_strerror(res));
87
88    /* Always cleanup */
89    curl_easy_cleanup(curl);
90  }
91
92  return (int)res;
93}
94