imap-tls.c (3577B)
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 * IMAP using TLS 27 * </DESC> 28 */ 29 30 #include <stdio.h> 31 #include <curl/curl.h> 32 33 /* This is a simple example showing how to fetch mail using libcurl's IMAP 34 * capabilities. It builds on the imap-fetch.c example adding transport 35 * security to protect the authentication details from being snooped. 36 * 37 * Note that this example requires libcurl 7.30.0 or above. 38 */ 39 40 int 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 fetches message 1 from the user's inbox */ 52 curl_easy_setopt(curl, CURLOPT_URL, 53 "imap://imap.example.com/INBOX/;UID=1"); 54 55 /* In this example, we start with a plain text connection, and upgrade to 56 * Transport Layer Security (TLS) using the STARTTLS command. Be careful 57 * of using CURLUSESSL_TRY here, because if TLS upgrade fails, the 58 * transfer continues anyway - see the security discussion in the libcurl 59 * tutorial for more details. */ 60 curl_easy_setopt(curl, CURLOPT_USE_SSL, (long)CURLUSESSL_ALL); 61 62 /* If your server does not have a valid certificate, then you can disable 63 * part of the Transport Layer Security protection by setting the 64 * CURLOPT_SSL_VERIFYPEER and CURLOPT_SSL_VERIFYHOST options to 0 (false). 65 * curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L); 66 * curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L); 67 * 68 * That is, in general, a bad idea. It is still better than sending your 69 * authentication details in plain text though. Instead, you should get 70 * the issuer certificate (or the host certificate if the certificate is 71 * self-signed) and add it to the set of certificates that are known to 72 * libcurl using CURLOPT_CAINFO and/or CURLOPT_CAPATH. See docs/SSLCERTS 73 * for more information. */ 74 curl_easy_setopt(curl, CURLOPT_CAINFO, "/path/to/certificate.pem"); 75 76 /* Since the traffic is encrypted, it is useful to turn on debug 77 * information within libcurl to see what is happening during the 78 * transfer */ 79 curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L); 80 81 /* Perform the fetch */ 82 res = curl_easy_perform(curl); 83 84 /* Check for errors */ 85 if(res != CURLE_OK) 86 fprintf(stderr, "curl_easy_perform() failed: %s\n", 87 curl_easy_strerror(res)); 88 89 /* Always cleanup */ 90 curl_easy_cleanup(curl); 91 } 92 93 return (int)res; 94 }