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1.1 ! misho 1: /*************************************************************************** ! 2: * _ _ ____ _ ! 3: * Project ___| | | | _ \| | ! 4: * / __| | | | |_) | | ! 5: * | (__| |_| | _ <| |___ ! 6: * \___|\___/|_| \_\_____| ! 7: * ! 8: * Copyright (C) 1998 - 2019, 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.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: /* <DESC> ! 24: * SMTP example using TLS ! 25: * </DESC> ! 26: */ ! 27: ! 28: #include <stdio.h> ! 29: #include <string.h> ! 30: #include <curl/curl.h> ! 31: ! 32: /* This is a simple example showing how to send mail using libcurl's SMTP ! 33: * capabilities. It builds on the smtp-mail.c example to add authentication ! 34: * and, more importantly, transport security to protect the authentication ! 35: * details from being snooped. ! 36: * ! 37: * Note that this example requires libcurl 7.20.0 or above. ! 38: */ ! 39: ! 40: #define FROM "<sender@example.org>" ! 41: #define TO "<addressee@example.net>" ! 42: #define CC "<info@example.org>" ! 43: ! 44: static const char *payload_text[] = { ! 45: "Date: Mon, 29 Nov 2010 21:54:29 +1100\r\n", ! 46: "To: " TO "\r\n", ! 47: "From: " FROM " (Example User)\r\n", ! 48: "Cc: " CC " (Another example User)\r\n", ! 49: "Message-ID: <dcd7cb36-11db-487a-9f3a-e652a9458efd@" ! 50: "rfcpedant.example.org>\r\n", ! 51: "Subject: SMTP TLS example message\r\n", ! 52: "\r\n", /* empty line to divide headers from body, see RFC5322 */ ! 53: "The body of the message starts here.\r\n", ! 54: "\r\n", ! 55: "It could be a lot of lines, could be MIME encoded, whatever.\r\n", ! 56: "Check RFC5322.\r\n", ! 57: NULL ! 58: }; ! 59: ! 60: struct upload_status { ! 61: int lines_read; ! 62: }; ! 63: ! 64: static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp) ! 65: { ! 66: struct upload_status *upload_ctx = (struct upload_status *)userp; ! 67: const char *data; ! 68: ! 69: if((size == 0) || (nmemb == 0) || ((size*nmemb) < 1)) { ! 70: return 0; ! 71: } ! 72: ! 73: data = payload_text[upload_ctx->lines_read]; ! 74: ! 75: if(data) { ! 76: size_t len = strlen(data); ! 77: memcpy(ptr, data, len); ! 78: upload_ctx->lines_read++; ! 79: ! 80: return len; ! 81: } ! 82: ! 83: return 0; ! 84: } ! 85: ! 86: int main(void) ! 87: { ! 88: CURL *curl; ! 89: CURLcode res = CURLE_OK; ! 90: struct curl_slist *recipients = NULL; ! 91: struct upload_status upload_ctx; ! 92: ! 93: upload_ctx.lines_read = 0; ! 94: ! 95: curl = curl_easy_init(); ! 96: if(curl) { ! 97: /* Set username and password */ ! 98: curl_easy_setopt(curl, CURLOPT_USERNAME, "user"); ! 99: curl_easy_setopt(curl, CURLOPT_PASSWORD, "secret"); ! 100: ! 101: /* This is the URL for your mailserver. Note the use of port 587 here, ! 102: * instead of the normal SMTP port (25). Port 587 is commonly used for ! 103: * secure mail submission (see RFC4403), but you should use whatever ! 104: * matches your server configuration. */ ! 105: curl_easy_setopt(curl, CURLOPT_URL, "smtp://mainserver.example.net:587"); ! 106: ! 107: /* In this example, we'll start with a plain text connection, and upgrade ! 108: * to Transport Layer Security (TLS) using the STARTTLS command. Be careful ! 109: * of using CURLUSESSL_TRY here, because if TLS upgrade fails, the transfer ! 110: * will continue anyway - see the security discussion in the libcurl ! 111: * tutorial for more details. */ ! 112: curl_easy_setopt(curl, CURLOPT_USE_SSL, (long)CURLUSESSL_ALL); ! 113: ! 114: /* If your server doesn't have a valid certificate, then you can disable ! 115: * part of the Transport Layer Security protection by setting the ! 116: * CURLOPT_SSL_VERIFYPEER and CURLOPT_SSL_VERIFYHOST options to 0 (false). ! 117: * curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L); ! 118: * curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L); ! 119: * That is, in general, a bad idea. It is still better than sending your ! 120: * authentication details in plain text though. Instead, you should get ! 121: * the issuer certificate (or the host certificate if the certificate is ! 122: * self-signed) and add it to the set of certificates that are known to ! 123: * libcurl using CURLOPT_CAINFO and/or CURLOPT_CAPATH. See docs/SSLCERTS ! 124: * for more information. */ ! 125: curl_easy_setopt(curl, CURLOPT_CAINFO, "/path/to/certificate.pem"); ! 126: ! 127: /* Note that this option isn't strictly required, omitting it will result ! 128: * in libcurl sending the MAIL FROM command with empty sender data. All ! 129: * autoresponses should have an empty reverse-path, and should be directed ! 130: * to the address in the reverse-path which triggered them. Otherwise, ! 131: * they could cause an endless loop. See RFC 5321 Section 4.5.5 for more ! 132: * details. ! 133: */ ! 134: curl_easy_setopt(curl, CURLOPT_MAIL_FROM, FROM); ! 135: ! 136: /* Add two recipients, in this particular case they correspond to the ! 137: * To: and Cc: addressees in the header, but they could be any kind of ! 138: * recipient. */ ! 139: recipients = curl_slist_append(recipients, TO); ! 140: recipients = curl_slist_append(recipients, CC); ! 141: curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients); ! 142: ! 143: /* We're using a callback function to specify the payload (the headers and ! 144: * body of the message). You could just use the CURLOPT_READDATA option to ! 145: * specify a FILE pointer to read from. */ ! 146: curl_easy_setopt(curl, CURLOPT_READFUNCTION, payload_source); ! 147: curl_easy_setopt(curl, CURLOPT_READDATA, &upload_ctx); ! 148: curl_easy_setopt(curl, CURLOPT_UPLOAD, 1L); ! 149: ! 150: /* Since the traffic will be encrypted, it is very useful to turn on debug ! 151: * information within libcurl to see what is happening during the transfer. ! 152: */ ! 153: curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L); ! 154: ! 155: /* Send the message */ ! 156: res = curl_easy_perform(curl); ! 157: ! 158: /* Check for errors */ ! 159: if(res != CURLE_OK) ! 160: fprintf(stderr, "curl_easy_perform() failed: %s\n", ! 161: curl_easy_strerror(res)); ! 162: ! 163: /* Free the list of recipients */ ! 164: curl_slist_free_all(recipients); ! 165: ! 166: /* Always cleanup */ ! 167: curl_easy_cleanup(curl); ! 168: } ! 169: ! 170: return (int)res; ! 171: }