1/***************************************************************************
2 *                                  _   _ ____  _
3 *  Project                     ___| | | |  _ \| |
4 *                             / __| | | | |_) | |
5 *                            | (__| |_| |  _ <| |___
6 *                             \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2014, 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#include <stdio.h>
23#include <curl/curl.h>
24
25/* This is a simple example showing how to retrieve mail using libcurl's POP3
26 * capabilities. It builds on the pop3-retr.c example adding transport
27 * security to protect the authentication details from being snooped.
28 *
29 * Note that this example requires libcurl 7.20.0 or above.
30 */
31
32int main(void)
33{
34  CURL *curl;
35  CURLcode res = CURLE_OK;
36
37  curl = curl_easy_init();
38  if(curl) {
39    /* Set username and password */
40    curl_easy_setopt(curl, CURLOPT_USERNAME, "user");
41    curl_easy_setopt(curl, CURLOPT_PASSWORD, "secret");
42
43    /* This will retreive message 1 from the user's mailbox */
44    curl_easy_setopt(curl, CURLOPT_URL, "pop3://pop.example.com/1");
45
46    /* In this example, we'll start with a plain text connection, and upgrade
47     * to Transport Layer Security (TLS) using the STLS command. Be careful of
48     * using CURLUSESSL_TRY here, because if TLS upgrade fails, the transfer
49     * will continue anyway - see the security discussion in the libcurl
50     * tutorial for more details. */
51    curl_easy_setopt(curl, CURLOPT_USE_SSL, (long)CURLUSESSL_ALL);
52
53    /* If your server doesn't have a valid certificate, then you can disable
54     * part of the Transport Layer Security protection by setting the
55     * CURLOPT_SSL_VERIFYPEER and CURLOPT_SSL_VERIFYHOST options to 0 (false).
56     *   curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
57     *   curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
58     * That is, in general, a bad idea. It is still better than sending your
59     * authentication details in plain text though.
60     * Instead, you should get the issuer certificate (or the host certificate
61     * if the certificate is self-signed) and add it to the set of certificates
62     * that are known to libcurl using CURLOPT_CAINFO and/or CURLOPT_CAPATH. See
63     * docs/SSLCERTS for more information. */
64    curl_easy_setopt(curl, CURLOPT_CAINFO, "/path/to/certificate.pem");
65
66    /* Since the traffic will be encrypted, it is very useful to turn on debug
67     * information within libcurl to see what is happening during the
68     * transfer */
69    curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
70
71    /* Perform the retr */
72    res = curl_easy_perform(curl);
73
74    /* Check for errors */
75    if(res != CURLE_OK)
76      fprintf(stderr, "curl_easy_perform() failed: %s\n",
77              curl_easy_strerror(res));
78
79    /* Always cleanup */
80    curl_easy_cleanup(curl);
81  }
82
83  return (int)res;
84}
85