citadel/server/modules/smtp/serv_smtpclient.c

   1 // Transmit outbound SMTP mail to the big wide world of the Internet
   2 //
   3 // This is the new, exciting, clever version that makes libcurl do all the work  :)
   4 //
   5 // Copyright (c) 1997-2024 by the citadel.org team
   6 //
   7 // This program is open source software.  Use, duplication, or disclosure
   8 // is subject to the terms of the GNU General Public License, version 3.
   9
  10 #include <stdlib.h>
  11 #include <unistd.h>
  12 #include <stdio.h>
  13 #include <time.h>
  14 #include <ctype.h>
  15 #include <string.h>
  16 #include <errno.h>
  17 #include <sys/types.h>
  18 #include <sys/stat.h>
  19 #include <libcitadel.h>
  20 #include <curl/curl.h>
  21 #include "../../sysconfig.h"
  22 #include "../../citadel_defs.h"
  23 #include "../../server.h"
  24 #include "../../citserver.h"
  25 #include "../../support.h"
  26 #include "../../config.h"
  27 #include "../../ctdl_module.h"
  28 #include "../../clientsocket.h"
  29 #include "../../msgbase.h"
  30 #include "../../domain.h"
  31 #include "../../internet_addressing.h"
  32 #include "../../citadel_dirs.h"
  33 #include "../smtp/smtp_util.h"
  34
  35 long last_queue_job_submitted = 0;
  36 long last_queue_job_processed = 0;
  37
  38 struct smtpmsgsrc {             // Data passed in and out of libcurl for message upload
  39         StrBuf *TheMessage;
  40         int bytes_total;
  41         int bytes_sent;
  42 };
  43
  44 // Initialize the SMTP outbound queue
  45 void smtp_init_spoolout(void) {
  46         struct ctdlroom qrbuf;
  47
  48         // Create the room.  This will silently fail if the room already
  49         // exists, and that's perfectly ok, because we want it to exist.
  50         CtdlCreateRoom(SMTP_SPOOLOUT_ROOM, 3, "", 0, 1, 0, VIEW_QUEUE);
  51
  52         // Make sure it's set to be a "system room" so it doesn't show up
  53         // in the <K>nown rooms list for administrators.
  54         if (CtdlGetRoomLock(&qrbuf, SMTP_SPOOLOUT_ROOM) == 0) {
  55                 qrbuf.QRflags2 |= QR2_SYSTEM;
  56                 CtdlPutRoomLock(&qrbuf);
  57         }
  58 }
  59
  60
  61 // For internet mail, generate a delivery job.
  62 // Yes, this is recursive.  Deal with it.  Infinite recursion does
  63 // not happen because the message containing the delivery job does not
  64 // have a recipient.
  65 int smtp_aftersave(struct CtdlMessage *msg, struct recptypes *recps) {
  66         if ((recps != NULL) && (recps->num_internet > 0)) {
  67                 struct CtdlMessage *imsg = NULL;
  68                 char recipient[SIZ];
  69                 StrBuf *SpoolMsg = NewStrBuf();
  70                 long nTokens;
  71                 int i;
  72
  73                 syslog(LOG_DEBUG, "smtpclient: generating delivery job");
  74
  75                 StrBufPrintf(SpoolMsg,
  76                              "Content-type: " SPOOLMIME "\n"
  77                              "\n"
  78                              "msgid|%s\n"
  79                              "submitted|%ld\n" "bounceto|%s\n", msg->cm_fields[eVltMsgNum], (long) time(NULL), recps->bounce_to);
  80
  81                 if (recps->envelope_from != NULL) {
  82                         StrBufAppendBufPlain(SpoolMsg, HKEY("envelope_from|"), 0);
  83                         StrBufAppendBufPlain(SpoolMsg, recps->envelope_from, -1, 0);
  84                         StrBufAppendBufPlain(SpoolMsg, HKEY("\n"), 0);
  85                 }
  86                 if (recps->sending_room != NULL) {
  87                         StrBufAppendBufPlain(SpoolMsg, HKEY("source_room|"), 0);
  88                         StrBufAppendBufPlain(SpoolMsg, recps->sending_room, -1, 0);
  89                         StrBufAppendBufPlain(SpoolMsg, HKEY("\n"), 0);
  90                 }
  91
  92                 nTokens = num_tokens(recps->recp_internet, '|');
  93                 for (i = 0; i < nTokens; i++) {
  94                         long len;
  95                         len = extract_token(recipient, recps->recp_internet, i, '|', sizeof recipient);
  96                         if (len > 0) {
  97                                 StrBufAppendBufPlain(SpoolMsg, HKEY("remote|"), 0);
  98                                 StrBufAppendBufPlain(SpoolMsg, recipient, len, 0);
  99                                 StrBufAppendBufPlain(SpoolMsg, HKEY("|0||\n"), 0);
 100                         }
 101                 }
 102
 103                 imsg = malloc(sizeof(struct CtdlMessage));
 104                 memset(imsg, 0, sizeof(struct CtdlMessage));
 105                 imsg->cm_magic = CTDLMESSAGE_MAGIC;
 106                 imsg->cm_anon_type = MES_NORMAL;
 107                 imsg->cm_format_type = FMT_RFC822;
 108                 CM_SetField(imsg, eMsgSubject, "QMSG");
 109                 CM_SetField(imsg, eAuthor, "Citadel");
 110                 CM_SetField(imsg, eJournal, "do not journal");
 111                 CM_SetAsFieldSB(imsg, eMessageText, &SpoolMsg);
 112                 last_queue_job_submitted = CtdlSubmitMsg(imsg, NULL, SMTP_SPOOLOUT_ROOM);
 113                 CM_Free(imsg);
 114         }
 115         return 0;
 116 }
 117
 118
 119 // Callback for smtp_attempt_delivery() to supply libcurl with upload data.
 120 static size_t upload_source(void *ptr, size_t size, size_t nmemb, void *userp) {
 121         struct smtpmsgsrc *s = (struct smtpmsgsrc *) userp;
 122         int sendbytes = 0;
 123         const char *send_this = NULL;
 124
 125         sendbytes = (size * nmemb);
 126
 127         if (s->bytes_sent >= s->bytes_total) {
 128                 return (0);                                     // no data remaining; we are done
 129         }
 130
 131         if (sendbytes > (s->bytes_total - s->bytes_sent)) {
 132                 sendbytes = s->bytes_total - s->bytes_sent;     // can't send more than we have
 133         }
 134
 135         send_this = ChrPtr(s->TheMessage);
 136         send_this += s->bytes_sent;                             // start where we last left off
 137
 138         memcpy(ptr, send_this, sendbytes);
 139         s->bytes_sent += sendbytes;
 140         return(sendbytes);                                      // return the number of bytes _actually_ copied
 141 }
 142
 143
 144 // The libcurl API doesn't provide a way to capture the actual SMTP result message returned
 145 // by the remote server.  This is an ugly way to extract it, by capturing debug data from
 146 // the library and filtering on the lines we want.
 147 int ctdl_libcurl_smtp_debug_callback(CURL *handle, curl_infotype type, char *data, size_t size, void *userptr) {
 148         if (type != CURLINFO_HEADER_IN)
 149                 return 0;
 150         if (!userptr)
 151                 return 0;
 152         char *debugbuf = (char *) userptr;
 153
 154         int len = strlen(debugbuf);
 155         if (len + size > SIZ)
 156                 return 0;
 157
 158         memcpy(&debugbuf[len], data, size);
 159         debugbuf[len + size] = 0;
 160         return 0;
 161 }
 162
 163
 164 // Go through the debug output of an SMTP transaction, and boil it down to just the final success or error response message.
 165 void trim_response(long response_code, char *response) {
 166         if ((response_code < 100) || (response_code > 999) || (IsEmptyStr(response))) {
 167                 return;
 168         }
 169
 170         char *p;
 171         for (p = response; *p != 0; ++p) {
 172                 if ( (*p != '\n') && (!isprint(*p)) ) {         // expunge any nonprintables except for newlines
 173                         *p = ' ';
 174                 }
 175         }
 176
 177         char response_code_str[4];
 178         snprintf(response_code_str, sizeof response_code_str, "%ld", response_code);
 179         char *respstart = strstr(response, response_code_str);
 180         if (respstart == NULL) {                                // If we have a response code but no response text,
 181                 strcpy(response, smtpstatus(response_code));    // use one of our canned messages.
 182                 return;
 183         }
 184         strcpy(response, respstart);
 185
 186         p = strstr(response, "\n");
 187         if (p != NULL) {
 188                 *p = 0;
 189         }
 190 }
 191
 192
 193 // Attempt a delivery to one recipient.
 194 // Returns a three-digit SMTP status code.
 195 int smtp_attempt_delivery(long msgid, char *recp, char *envelope_from, char *source_room, char *response) {
 196         struct smtpmsgsrc s;
 197         char *fromaddr = NULL;
 198         CURL *curl;
 199         CURLcode res = CURLE_OK;
 200         struct curl_slist *recipients = NULL;
 201         long response_code = 421;
 202         int num_mx = 0;
 203         char mxes[SIZ];
 204         char user[1024];
 205         char node[1024];
 206         char name[1024];
 207         char try_this_mx[256];
 208         char smtp_url[512];
 209         int i;
 210
 211         syslog(LOG_DEBUG, "smtpclient: smtp_attempt_delivery(%ld, %s)", msgid, recp);
 212
 213         process_rfc822_addr(recp, user, node, name);    // split recipient address into username, hostname, displayname
 214         num_mx = getmx(mxes, node);
 215         if (num_mx < 1) {
 216                 return(421);
 217         }
 218
 219         CC->redirect_buffer = NewStrBufPlain(NULL, SIZ);
 220
 221         // If we have a source room, it's probably a mailing list message; generate an unsubscribe header
 222         if (!IsEmptyStr(source_room)) {
 223                 char base_url[SIZ];
 224                 char unsubscribe_url[SIZ];
 225                 snprintf(base_url, sizeof base_url, "https://%s/listsub", CtdlGetConfigStr("c_fqdn"));
 226                 generate_one_click_url(unsubscribe_url, base_url, "unsubscribe", source_room, recp);
 227                 cprintf("List-Unsubscribe: %s\r\n", unsubscribe_url);
 228                 cprintf("List-Unsubscribe-Post: List-Unsubscribe=One-Click\r\n");       // RFC 8058
 229
 230         }
 231
 232         CtdlOutputMsg(msgid, MT_RFC822, HEADERS_ALL, 0, 1, NULL, 0, NULL, &fromaddr, NULL);
 233         s.TheMessage = CC->redirect_buffer;
 234         CC->redirect_buffer = NULL;
 235         syslog(LOG_DEBUG, "fromaddr=<%s>",fromaddr);
 236
 237         // If we have a DKIM key, try to sign the message.
 238         char *dkim_private_key = CtdlGetConfigStr("dkim_private_key");
 239         char *dkim_selector = CtdlGetConfigStr("dkim_selector");
 240         char *dkim_from_domain = (strchr(fromaddr, '@') ? strchr(fromaddr, '@')+1 : NULL);
 241         if (
 242                 !IsEmptyStr(dkim_from_domain)                   // Is the sending domain non-empty?
 243                 && IsDirectory(fromaddr, 0)                     // and is it one of "our" domains?
 244                 && !IsEmptyStr(dkim_private_key)                // Do we have a private signing key?
 245                 && !IsEmptyStr(dkim_selector)                   // and a selector to go with it?
 246         ) {
 247                 char *pkey = strdup(dkim_private_key);          // If you answered "yes" to all of the above questions,
 248                 if (pkey) {                                     // congratulations!  We get to DKIM-sign the message!
 249                         char *sp;
 250                         while (sp = strchr(pkey, '_')) {        // The dkim_private_key record contains our RSA private key,
 251                                 *sp = '\n';                     // but we have to convert all the newlines back to underscores.
 252                         }
 253                         syslog(LOG_DEBUG, "smtpclient: dkim-signing with private key for selector <%s> domain <%s>",
 254                                 dkim_selector, dkim_from_domain);
 255                         dkim_sign(s.TheMessage, pkey, dkim_from_domain, dkim_selector);
 256                         free(pkey);
 257                 }
 258         }
 259
 260         // Prepare the buffer for transmittal
 261         s.bytes_total = StrLength(s.TheMessage);
 262         s.bytes_sent = 0;
 263         response_code = 421;
 264
 265
 266         // Keep trying MXes until one works or we run out.
 267         for (i = 0; ((i < num_mx) && ((response_code / 100) == 4)); ++i) {
 268                 response_code = 421;    // default 421 makes non-protocol errors transient
 269                 s.bytes_sent = 0;       // rewind our buffer in case we try multiple MXes
 270
 271                 curl = curl_easy_init();
 272                 if (curl) {
 273                         response[0] = 0;
 274
 275                         if (!IsEmptyStr(envelope_from)) {
 276                                 curl_easy_setopt(curl, CURLOPT_MAIL_FROM, envelope_from);
 277                         }
 278                         else {
 279                                 curl_easy_setopt(curl, CURLOPT_MAIL_FROM, fromaddr);
 280                         }
 281
 282                         recipients = curl_slist_append(recipients, recp);
 283                         curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);
 284                         curl_easy_setopt(curl, CURLOPT_READFUNCTION, upload_source);
 285                         curl_easy_setopt(curl, CURLOPT_READDATA, &s);
 286                         curl_easy_setopt(curl, CURLOPT_UPLOAD, 1);                              // tell libcurl we are uploading
 287                         curl_easy_setopt(curl, CURLOPT_TIMEOUT, 20L);                           // Time out after 20 seconds
 288                         if (CtdlGetConfigInt("c_smtpclient_disable_starttls") == 0) {
 289                                 curl_easy_setopt(curl, CURLOPT_USE_SSL, CURLUSESSL_TRY);        // Attempt STARTTLS if offered
 290                         }
 291                         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
 292                         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
 293                         curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, ctdl_libcurl_smtp_debug_callback);
 294                         curl_easy_setopt(curl, CURLOPT_DEBUGDATA, (void *) response);
 295                         curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
 296
 297                         // Construct an SMTP URL in the form of:
 298                         //      smtp[s]://target_host/source_host
 299                         // This looks weird but libcurl uses that last part to set our name for EHLO or HELO.
 300                         // We check for "smtp://" and "smtps://" because an admin may have put those prefixes in a smart-host entry
 301                         // If there is no prefix we add "smtp://"
 302                         extract_token(try_this_mx, mxes, i, '|', (sizeof try_this_mx - 7));
 303                         snprintf(smtp_url, sizeof smtp_url,
 304                                 "%s%s/%s",
 305                                 (((!strncasecmp(try_this_mx, HKEY("smtp://")))
 306                                 || (!strncasecmp(try_this_mx, HKEY("smtps://")))) ? "" : "smtp://"),
 307                                 try_this_mx, CtdlGetConfigStr("c_fqdn")
 308                         );
 309                         curl_easy_setopt(curl, CURLOPT_URL, smtp_url);
 310                         syslog(LOG_DEBUG, "smtpclient: trying MX %d of %d <%s>", i+1, num_mx, smtp_url);        // send the message
 311                         res = curl_easy_perform(curl);
 312                         curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &response_code);
 313                         syslog(LOG_DEBUG,
 314                                "smtpclient: libcurl returned %d (%s) , SMTP response %ld",
 315                                res, curl_easy_strerror(res), response_code
 316                         );
 317
 318                         if ((res != CURLE_OK) && (response_code == 0)) {        // check for errors
 319                                 response_code = 421;
 320                         }
 321
 322                         curl_slist_free_all(recipients);
 323                         recipients = NULL;                                      // this gets reused; avoid double-free
 324                         curl_easy_cleanup(curl);
 325                         curl = NULL;                                            // this gets reused; avoid double-free
 326
 327                         // Trim the error message buffer down to just the actual message
 328                         trim_response(response_code, response);
 329                 }
 330         }
 331
 332         FreeStrBuf(&s.TheMessage);
 333         if (fromaddr) {
 334                 free(fromaddr);
 335         }
 336         return ((int) response_code);
 337 }
 338
 339
 340 // Process one outbound message.
 341 void smtp_process_one_msg(long qmsgnum) {
 342         struct CtdlMessage *msg = NULL;
 343         char *instr = NULL;
 344         int i;
 345         int num_success = 0;
 346         int num_fail = 0;
 347         int num_delayed = 0;
 348         long deletes[2];
 349         int delete_this_queue = 0;
 350         char server_response[SIZ];
 351
 352         msg = CtdlFetchMessage(qmsgnum, 1);
 353         if (msg == NULL) {
 354                 syslog(LOG_WARNING, "smtpclient: msg#%ld does not exist", qmsgnum);
 355                 return;
 356         }
 357
 358         instr = msg->cm_fields[eMessageText];
 359         msg->cm_fields[eMessageText] = NULL;
 360         CM_Free(msg);
 361
 362         // if the queue job message has any CRLF's convert them to LF's
 363         char *crlf = NULL;
 364         while (crlf = strstr(instr, "\r\n"), crlf != NULL) {
 365                 strcpy(crlf, crlf + 1);
 366         }
 367
 368         // Strip out the headers and we are now left with just the instructions.
 369         char *soi = strstr(instr, "\n\n");
 370         if (soi) {
 371                 strcpy(instr, soi + 2);
 372         }
 373
 374         long msgid = 0;
 375         time_t submitted = time(NULL);
 376         time_t attempted = 0;
 377         char *bounceto = NULL;
 378         char *envelope_from = NULL;
 379         char *source_room = NULL;
 380
 381         char cfgline[SIZ];
 382         for (i = 0; i < num_tokens(instr, '\n'); ++i) {
 383                 extract_token(cfgline, instr, i, '\n', sizeof cfgline);
 384                 if (!strncasecmp(cfgline, HKEY("msgid|")))              msgid = atol(&cfgline[6]);
 385                 if (!strncasecmp(cfgline, HKEY("submitted|")))          submitted = atol(&cfgline[10]);
 386                 if (!strncasecmp(cfgline, HKEY("attempted|")))          attempted = atol(&cfgline[10]);
 387                 if (!strncasecmp(cfgline, HKEY("bounceto|")))           bounceto = strdup(&cfgline[9]);
 388                 if (!strncasecmp(cfgline, HKEY("envelope_from|")))      envelope_from = strdup(&cfgline[14]);
 389                 if (!strncasecmp(cfgline, HKEY("source_room|")))        source_room = strdup(&cfgline[12]);
 390         }
 391
 392         int should_try_now = 0;
 393         if (attempted < submitted) {                    // If no attempts have been made yet, try now
 394                 should_try_now = 1;
 395         }
 396         else if ((attempted - submitted) <= 14400) {
 397                 if ((time(NULL) - attempted) > 1800) {  // First four hours, retry every 30 minutes
 398                         should_try_now = 1;
 399                 }
 400         }
 401         else {
 402                 if ((time(NULL) - attempted) > 14400) { // After that, retry once every 4 hours
 403                         should_try_now = 1;
 404                 }
 405         }
 406
 407         if (should_try_now) {
 408                 syslog(LOG_DEBUG, "smtpclient: attempting delivery of message <%ld> now", qmsgnum);
 409                 if (source_room) {
 410                         syslog(LOG_DEBUG, "smtpclient: this message originated in <%s>", source_room);
 411                 }
 412                 StrBuf *NewInstr = NewStrBuf();
 413                 StrBufAppendPrintf(NewInstr, "Content-type: " SPOOLMIME "\n\n");
 414                 StrBufAppendPrintf(NewInstr, "msgid|%ld\n", msgid);
 415                 StrBufAppendPrintf(NewInstr, "submitted|%ld\n", submitted);
 416                 if (bounceto) {
 417                         StrBufAppendPrintf(NewInstr, "bounceto|%s\n", bounceto);
 418                 }
 419                 if (envelope_from) {
 420                         StrBufAppendPrintf(NewInstr, "envelope_from|%s\n", envelope_from);
 421                 }
 422                 for (i = 0; i < num_tokens(instr, '\n'); ++i) {
 423                         extract_token(cfgline, instr, i, '\n', sizeof cfgline);
 424                         if (!strncasecmp(cfgline, HKEY("remote|"))) {
 425                                 char recp[SIZ];
 426                                 int previous_result = extract_int(cfgline, 2);
 427                                 if ((previous_result == 0) || (previous_result == 4)) {
 428                                         int new_result = 421;
 429                                         extract_token(recp, cfgline, 1, '|', sizeof recp);
 430                                         new_result = smtp_attempt_delivery(msgid, recp, envelope_from, source_room, server_response);
 431                                         syslog(LOG_DEBUG, "smtpclient: recp: <%s> , result: %d (%s)", recp, new_result, server_response);
 432                                         if ((new_result / 100) == 2) {
 433                                                 ++num_success;
 434                                         }
 435                                         else {
 436                                                 if ((new_result / 100) == 5) {
 437                                                         ++num_fail;
 438                                                 }
 439                                                 else {
 440                                                         ++num_delayed;
 441                                                 }
 442                                                 StrBufAppendPrintf(NewInstr, "remote|%s|%ld|%ld (%s)\n", recp, (new_result / 100), new_result, server_response);
 443                                         }
 444                                 }
 445                         }
 446                 }
 447
 448                 StrBufAppendPrintf(NewInstr, "attempted|%ld\n", time(NULL));
 449
 450                 // All deliveries have now been attempted.  Now determine the disposition of this queue entry.
 451
 452                 time_t age = time(NULL) - submitted;
 453                 syslog(LOG_DEBUG,
 454                        "smtpclient: submission age: %ldd%ldh%ldm%lds",
 455                        (age / 86400), ((age % 86400) / 3600), ((age % 3600) / 60), (age % 60));
 456                 syslog(LOG_DEBUG, "smtpclient: num_success=%d , num_fail=%d , num_delayed=%d", num_success, num_fail, num_delayed);
 457
 458                 // If there are permanent fails on this attempt, deliver a bounce to the user.
 459                 // The 5XX fails will be recorded in the rewritten queue, but they will be removed before the next attempt.
 460                 if (num_fail > 0) {
 461                         smtp_do_bounce(ChrPtr(NewInstr), SDB_BOUNCE_FATALS);
 462                 }
 463                 // If all deliveries have either succeeded or failed, we are finished with this queue entry.
 464                 if (num_delayed == 0) {
 465                         delete_this_queue = 1;
 466                 }
 467                 // If it's been more than five days, give up and tell the sender that delivery failed
 468                 else if ((time(NULL) - submitted) > SMTP_DELIVER_FAIL) {
 469                         smtp_do_bounce(ChrPtr(NewInstr), SDB_BOUNCE_ALL);
 470                         delete_this_queue = 1;
 471                 }
 472                 // If it's been more than four hours but less than five days, warn the sender that delivery is delayed
 473                 else if (((attempted - submitted) < SMTP_DELIVER_WARN) && ((time(NULL) - submitted) >= SMTP_DELIVER_WARN)) {
 474                         smtp_do_bounce(ChrPtr(NewInstr), SDB_WARN);
 475                 }
 476
 477                 if (delete_this_queue) {
 478                         syslog(LOG_DEBUG, "smtpclient: %ld deleting", qmsgnum);
 479                         deletes[0] = qmsgnum;
 480                         deletes[1] = msgid;
 481                         CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, deletes, 2, "");
 482                         FreeStrBuf(&NewInstr);  // We have to free NewInstr here, no longer needed
 483                 }
 484                 else {
 485                         // replace the old queue entry with the new one
 486                         syslog(LOG_DEBUG, "smtpclient: %ld rewriting", qmsgnum);
 487                         msg = convert_internet_message_buf(&NewInstr);  // This function will free NewInstr for us
 488                         CtdlSubmitMsg(msg, NULL, SMTP_SPOOLOUT_ROOM);
 489                         CM_Free(msg);
 490                         CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, &qmsgnum, 1, "");
 491                 }
 492         }
 493         else {
 494                 syslog(LOG_DEBUG, "smtpclient: msg#%ld retry time not reached", qmsgnum);
 495         }
 496
 497         if (bounceto != NULL) {
 498                 free(bounceto);
 499         }
 500         if (envelope_from != NULL) {
 501                 free(envelope_from);
 502         }
 503         if (source_room != NULL) {
 504                 free(source_room);
 505         }
 506         free(instr);
 507 }
 508
 509
 510 // Callback for smtp_do_queue()
 511 void smtp_add_msg(long msgnum, void *userdata) {
 512         Array *smtp_queue = (Array *) userdata;
 513         array_append(smtp_queue, &msgnum);
 514 }
 515
 516
 517 enum {
 518         FULL_QUEUE_RUN,         // try to process the entire queue, including messages that have already been attempted
 519         QUICK_QUEUE_RUN         // only process jobs in the queue that have not been tried yet
 520 };
 521
 522
 523 // Run through the queue sending out messages.
 524 void smtp_do_queue(int type_of_queue_run) {
 525         static int doing_smtpclient = 0;
 526         int i = 0;
 527
 528         // This is a concurrency check to make sure only one smtpclient run is done at a time.
 529         begin_critical_section(S_SMTPQUEUE);
 530         if (doing_smtpclient) {
 531                 end_critical_section(S_SMTPQUEUE);
 532                 return;
 533         }
 534         doing_smtpclient = 1;
 535         end_critical_section(S_SMTPQUEUE);
 536
 537         syslog(LOG_DEBUG, "smtpclient: start %s queue run , last_queue_job_processed=%ld , last_queue_job_submitted=%ld",
 538                 (type_of_queue_run == QUICK_QUEUE_RUN ? "quick" : "full"),
 539                 last_queue_job_processed, last_queue_job_submitted
 540         );
 541
 542         if (CtdlGetRoom(&CC->room, SMTP_SPOOLOUT_ROOM) != 0) {
 543                 syslog(LOG_WARNING, "smtpclient: cannot find room <%s>", SMTP_SPOOLOUT_ROOM);
 544                 doing_smtpclient = 0;
 545                 return;
 546         }
 547
 548         // This array will hold the list of queue job messages
 549         Array *smtp_queue = array_new(sizeof(long));
 550         if (smtp_queue == NULL) {
 551                 syslog(LOG_WARNING, "smtpclient: cannot allocate queue array");
 552                 doing_smtpclient = 0;
 553                 return;
 554         }
 555
 556         // Put the queue in memory so we can close the db cursor
 557         CtdlForEachMessage(
 558                 (type_of_queue_run == QUICK_QUEUE_RUN ? MSGS_GT : MSGS_ALL),            // quick = new jobs; full = all jobs
 559                 (type_of_queue_run == QUICK_QUEUE_RUN ? last_queue_job_processed : 0),  // quick = new jobs; full = all jobs
 560                 NULL,
 561                 SPOOLMIME,              // Searching for Content-type of SPOOLIME will give us only queue instruction messages
 562                 NULL,
 563                 smtp_add_msg,           // That's our callback function to add a job to the queue
 564                 (void *)smtp_queue
 565         );
 566
 567         // We are ready to run through the queue now.
 568         syslog(LOG_DEBUG, "smtpclient: %d messages to be processed", array_len(smtp_queue));
 569         for (i = 0; i < array_len(smtp_queue); ++i) {
 570                 long m;
 571                 memcpy(&m, array_get_element_at(smtp_queue, i), sizeof(long));
 572                 smtp_process_one_msg(m);
 573         }
 574
 575         array_free(smtp_queue);
 576         last_queue_job_processed = last_queue_job_submitted;
 577         doing_smtpclient = 0;
 578         syslog(LOG_DEBUG, "smtpclient: end %s queue run , last_queue_job_processed=%ld , last_queue_job_submitted=%ld",
 579                 (type_of_queue_run == QUICK_QUEUE_RUN ? "quick" : "full"),
 580                 last_queue_job_processed, last_queue_job_submitted
 581         );
 582 }
 583
 584
 585 // The "full" queue run goes through the entire queue, attempting delivery for newly submitted messages,
 586 // retrying failed deliveries periodically, and handling undeliverable messages.
 587 void smtp_do_queue_full(void) {
 588         smtp_do_queue(FULL_QUEUE_RUN);
 589 }
 590
 591
 592 // The "quick" queue run only handles newly submitted messages, allowing them to be delivered immediately
 593 // instead of waiting for the next "full" queue run.
 594 void smtp_do_queue_quick(void) {
 595         if (last_queue_job_submitted > last_queue_job_processed) {
 596                 smtp_do_queue(QUICK_QUEUE_RUN);
 597         }
 598 }
 599
 600
 601 // Initialization function, called from modules_init.c
 602 char *ctdl_module_init_smtpclient(void) {
 603         if (!threading) {
 604                 CtdlRegisterMessageHook(smtp_aftersave, EVT_AFTERSAVE);
 605                 CtdlRegisterSessionHook(smtp_do_queue_quick, EVT_HOUSE, PRIO_AGGR + 51);
 606                 CtdlRegisterSessionHook(smtp_do_queue_full, EVT_TIMER, PRIO_AGGR + 51);
 607                 smtp_init_spoolout();
 608                 dkim_init();
 609         }
 610
 611         // return our module id for the log
 612         return "smtpclient";
 613 }