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/*****************************************************************************
* _ _ ____ _
* Project ___| | | | _ \| |
* / __| | | | |_) | |
* | (__| |_| | _ <| |___
* \___|\___/|_| \_\_____|
*
*/
#include <stdio.h>
#include <string.h>
#include <curl/curl.h>
/* This is a simple example showing how to send mail using libcurl's SMTP
* capabilities. It builds on the simplesmtp.c example, adding some
* authentication and transport security.
*/
#define FROM "<sender@example.org>"
#define TO "<addressee@example.net>"
#define CC "<info@example.org>"
static const char *payload_text[]={
"Date: Mon, 29 Nov 2010 21:54:29 +1100\n",
"To: " TO "\n",
"From: " FROM "(Example User)\n",
"Cc: " CC "(Another example User)\n",
"Message-ID: <dcd7cb36-11db-487a-9f3a-e652a9458efd@rfcpedant.example.org>\n",
"Subject: SMTP TLS example message\n",
"\n", /* empty line to divide headers from body, see RFC5322 */
"The body of the message starts here.\n",
"\n",
"It could be a lot of lines, could be MIME encoded, whatever.\n",
"Check RFC5322.\n",
NULL
};
struct upload_status {
int lines_read;
};
static size_t payload_source(void *ptr, size_t size, size_t nmemb, void *userp)
{
struct upload_status *upload_ctx = (struct upload_status *)userp;
const char *data;
if ((size == 0) || (nmemb == 0) || ((size*nmemb) < 1)) {
return 0;
}
data = payload_text[upload_ctx->lines_read];
if (data) {
size_t len = strlen(data);
memcpy(ptr, data, len);
upload_ctx->lines_read ++;
return len;
}
return 0;
}
int main(void)
{
CURL *curl;
CURLcode res;
struct curl_slist *recipients = NULL;
struct upload_status upload_ctx;
upload_ctx.lines_read = 0;
curl = curl_easy_init();
if (curl) {
/* This is the URL for your mailserver. Note the use of port 587 here,
* instead of the normal SMTP port (25). Port 587 is commonly used for
* secure mail submission (see RFC4403), but you should use whatever
* matches your server configuration. */
curl_easy_setopt(curl, CURLOPT_URL, "smtp://mainserver.example.net:587");
/* In this example, we'll start with a plain text connection, and upgrade
* to Transport Layer Security (TLS) using the STARTTLS command. Be careful
* of using CURLUSESSL_TRY here, because if TLS upgrade fails, the transfer
* will continue anyway - see the security discussion in the libcurl
* tutorial for more details. */
curl_easy_setopt(curl, CURLOPT_USE_SSL, CURLUSESSL_ALL);
/* If your server doesn't have a valid certificate, then you can disable
* part of the Transport Layer Security protection by setting the
* CURLOPT_SSL_VERIFYPEER and CURLOPT_SSL_VERIFYHOST options to 0 (false).
* curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0);
* curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0);
* That is, in general, a bad idea. It is still better than sending your
* authentication details in plain text though.
* Instead, you should get the issuer certificate (or the host certificate
* if the certificate is self-signed) and add it to the set of certificates
* that are known to libcurl using CURLOPT_CAINFO and/or CURLOPT_CAPATH. See
* docs/SSLCERTS for more information.
*/
curl_easy_setopt(curl, CURLOPT_CAINFO, "/path/to/certificate.pem");
/* A common reason for requiring transport security is to protect
* authentication details (user names and passwords) from being "snooped"
* on the network. Here is how the user name and password are provided: */
curl_easy_setopt(curl, CURLOPT_USERNAME, "user@example.net");
curl_easy_setopt(curl, CURLOPT_PASSWORD, "P@ssw0rd");
/* value for envelope reverse-path */
curl_easy_setopt(curl, CURLOPT_MAIL_FROM, FROM);
/* Add two recipients, in this particular case they correspond to the
* To: and Cc: addressees in the header, but they could be any kind of
* recipient. */
recipients = curl_slist_append(recipients, TO);
recipients = curl_slist_append(recipients, CC);
curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);
/* In this case, we're using a callback function to specify the data. You
* could just use the CURLOPT_READDATA option to specify a FILE pointer to
* read from.
*/
curl_easy_setopt(curl, CURLOPT_READFUNCTION, payload_source);
curl_easy_setopt(curl, CURLOPT_READDATA, &upload_ctx);
/* Since the traffic will be encrypted, it is very useful to turn on debug
* information within libcurl to see what is happening during the transfer.
*/
curl_easy_setopt(curl, CURLOPT_VERBOSE, 1);
/* send the message (including headers) */
res = curl_easy_perform(curl);
/* free the list of recipients and clean up */
curl_slist_free_all(recipients);
curl_easy_cleanup(curl);
}
return 0;
}
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