On Friday, December 17, 2010 10:30:52 am Daniel Stenberg wrote: > Yes, I added support for that old legacy style mostly because we already do > support ftps:// that way and it was very easy to do. I don't know if anyone > these days actually use that concept. My (quite reasonable) ISP offers it.
> >> Giving an example of how you do *that* would be a more useful thing to > >> do in a comment. Bonus points for mentioning that you would hopefully > >> expect this to be connecting to port 587 rather than port 25 (RFC4409). I think I'll take the bonus on this :-) > Making two examples certainly isn't a bad idea, but perhaps this little > tiny option doesn't warrant a separate one? You make libcurl use STARTTLS > by setting the CURLOPT_USE_SSL option accordingly. Nothing about SSL is tiny :-) I think the second example makes a nice graduation between the first (really simple) SMTP example, and the multi-SMTP example. Here is, for first review: /***************************************************************************** * _ _ ____ _ * 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 "[email protected]" #define TO "[email protected]" #define CC "[email protected]" 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" "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, "[email protected]"); 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; } ------------------------------------------------------------------- List admin: http://cool.haxx.se/list/listinfo/curl-library Etiquette: http://curl.haxx.se/mail/etiquette.html
