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Remove preprocessor tests for OpenSSL. It's a requirement.
[citadel.git] / 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);                 // RFC 2369
228                 cprintf("List-Unsubscribe-Post: List-Unsubscribe=One-Click\r\n");       // RFC 8058
229         }
230
231         CtdlOutputMsg(msgid, MT_RFC822, HEADERS_ALL, 0, 1, NULL, 0, NULL, &fromaddr, NULL);
232         s.TheMessage = CC->redirect_buffer;
233         CC->redirect_buffer = NULL;
234
235         // If we have a DKIM key, try to sign the message.
236         char *dkim_private_key = CtdlGetConfigStr("dkim_private_key");
237         char *dkim_selector = CtdlGetConfigStr("dkim_selector");
238         char *dkim_from_domain = (strchr(fromaddr, '@') ? strchr(fromaddr, '@')+1 : NULL);
239         if (
240                 !IsEmptyStr(dkim_from_domain)                   // Is the sending domain non-empty?
241                 && IsDirectory(fromaddr, 0)                     // and is it one of "our" domains?
242                 && !IsEmptyStr(dkim_private_key)                // Do we have a private signing key?
243                 && !IsEmptyStr(dkim_selector)                   // and a selector to go with it?
244         ) {
245                 // If you answered "yes" to all of the above questions, congratulations!  We get to sign the message!
246                 syslog(LOG_DEBUG, "smtpclient: dkim-signing for selector <%s> in domain <%s>", dkim_selector, dkim_from_domain);
247
248                 // Remember, the dkim_sign() function is capable of handling a PEM-encoded PKCS#7 private key that
249                 // has had all of its newlines replaced by underscores -- which is exactly how we store it.
250                 dkim_sign(s.TheMessage,dkim_private_key, dkim_from_domain, dkim_selector);
251         }
252
253         // Prepare the buffer for transmittal
254         s.bytes_total = StrLength(s.TheMessage);
255         s.bytes_sent = 0;
256         response_code = 421;
257
258
259         // Keep trying MXes until one works or we run out.
260         for (i = 0; ((i < num_mx) && ((response_code / 100) == 4)); ++i) {
261                 response_code = 421;    // default 421 makes non-protocol errors transient
262                 s.bytes_sent = 0;       // rewind our buffer in case we try multiple MXes
263
264                 curl = curl_easy_init();
265                 if (curl) {
266                         response[0] = 0;
267
268                         if (!IsEmptyStr(envelope_from)) {
269                                 curl_easy_setopt(curl, CURLOPT_MAIL_FROM, envelope_from);
270                         }
271                         else {
272                                 curl_easy_setopt(curl, CURLOPT_MAIL_FROM, fromaddr);
273                         }
274
275                         recipients = curl_slist_append(recipients, recp);
276                         curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);
277                         curl_easy_setopt(curl, CURLOPT_READFUNCTION, upload_source);
278                         curl_easy_setopt(curl, CURLOPT_READDATA, &s);
279                         curl_easy_setopt(curl, CURLOPT_UPLOAD, 1);                              // tell libcurl we are uploading
280                         curl_easy_setopt(curl, CURLOPT_TIMEOUT, 20L);                           // Time out after 20 seconds
281                         if (CtdlGetConfigInt("c_smtpclient_disable_starttls") == 0) {
282                                 curl_easy_setopt(curl, CURLOPT_USE_SSL, CURLUSESSL_TRY);        // Attempt STARTTLS if offered
283                         }
284                         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
285                         curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
286                         curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, ctdl_libcurl_smtp_debug_callback);
287                         curl_easy_setopt(curl, CURLOPT_DEBUGDATA, (void *) response);
288                         curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
289
290                         // Construct an SMTP URL in the form of:
291                         //      smtp[s]://target_host/source_host
292                         // This looks weird but libcurl uses that last part to set our name for EHLO or HELO.
293                         // We check for "smtp://" and "smtps://" because an admin may have put those prefixes in a smart-host entry
294                         // If there is no prefix we add "smtp://"
295                         extract_token(try_this_mx, mxes, i, '|', (sizeof try_this_mx - 7));
296                         snprintf(smtp_url, sizeof smtp_url,
297                                 "%s%s/%s",
298                                 (((!strncasecmp(try_this_mx, HKEY("smtp://")))
299                                 || (!strncasecmp(try_this_mx, HKEY("smtps://")))) ? "" : "smtp://"),
300                                 try_this_mx, CtdlGetConfigStr("c_fqdn")
301                         );
302                         curl_easy_setopt(curl, CURLOPT_URL, smtp_url);
303                         syslog(LOG_DEBUG, "smtpclient: trying MX %d of %d <%s>", i+1, num_mx, smtp_url);        // send the message
304                         res = curl_easy_perform(curl);
305                         curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &response_code);
306                         syslog(LOG_DEBUG,
307                                "smtpclient: libcurl returned %d (%s) , SMTP response %ld",
308                                res, curl_easy_strerror(res), response_code
309                         );
310
311                         if ((res != CURLE_OK) && (response_code == 0)) {        // check for errors
312                                 response_code = 421;
313                         }
314
315                         curl_slist_free_all(recipients);
316                         recipients = NULL;                                      // this gets reused; avoid double-free
317                         curl_easy_cleanup(curl);
318                         curl = NULL;                                            // this gets reused; avoid double-free
319
320                         // Trim the error message buffer down to just the actual message
321                         trim_response(response_code, response);
322                 }
323         }
324
325         FreeStrBuf(&s.TheMessage);
326         if (fromaddr) {
327                 free(fromaddr);
328         }
329         return ((int) response_code);
330 }
331
332
333 // Process one outbound message.
334 void smtp_process_one_msg(long qmsgnum) {
335         struct CtdlMessage *msg = NULL;
336         char *instr = NULL;
337         int i;
338         int num_success = 0;
339         int num_fail = 0;
340         int num_delayed = 0;
341         long deletes[2];
342         int delete_this_queue = 0;
343         char server_response[SIZ];
344
345         msg = CtdlFetchMessage(qmsgnum, 1);
346         if (msg == NULL) {
347                 syslog(LOG_WARNING, "smtpclient: msg#%ld does not exist", qmsgnum);
348                 return;
349         }
350
351         instr = msg->cm_fields[eMessageText];
352         msg->cm_fields[eMessageText] = NULL;
353         CM_Free(msg);
354
355         // if the queue job message has any CRLF's convert them to LF's
356         char *crlf = NULL;
357         while (crlf = strstr(instr, "\r\n"), crlf != NULL) {
358                 strcpy(crlf, crlf + 1);
359         }
360
361         // Strip out the headers and we are now left with just the instructions.
362         char *soi = strstr(instr, "\n\n");
363         if (soi) {
364                 strcpy(instr, soi + 2);
365         }
366
367         long msgid = 0;
368         time_t submitted = time(NULL);
369         time_t attempted = 0;
370         char *bounceto = NULL;
371         char *envelope_from = NULL;
372         char *source_room = NULL;
373
374         char cfgline[SIZ];
375         for (i = 0; i < num_tokens(instr, '\n'); ++i) {
376                 extract_token(cfgline, instr, i, '\n', sizeof cfgline);
377                 if (!strncasecmp(cfgline, HKEY("msgid|")))              msgid = atol(&cfgline[6]);
378                 if (!strncasecmp(cfgline, HKEY("submitted|")))          submitted = atol(&cfgline[10]);
379                 if (!strncasecmp(cfgline, HKEY("attempted|")))          attempted = atol(&cfgline[10]);
380                 if (!strncasecmp(cfgline, HKEY("bounceto|")))           bounceto = strdup(&cfgline[9]);
381                 if (!strncasecmp(cfgline, HKEY("envelope_from|")))      envelope_from = strdup(&cfgline[14]);
382                 if (!strncasecmp(cfgline, HKEY("source_room|")))        source_room = strdup(&cfgline[12]);
383         }
384
385         int should_try_now = 0;
386         if (attempted < submitted) {                    // If no attempts have been made yet, try now
387                 should_try_now = 1;
388         }
389         else if ((attempted - submitted) <= 14400) {
390                 if ((time(NULL) - attempted) > 1800) {  // First four hours, retry every 30 minutes
391                         should_try_now = 1;
392                 }
393         }
394         else {
395                 if ((time(NULL) - attempted) > 14400) { // After that, retry once every 4 hours
396                         should_try_now = 1;
397                 }
398         }
399
400         if (should_try_now) {
401                 syslog(LOG_DEBUG, "smtpclient: attempting delivery of message <%ld> now", qmsgnum);
402                 if (source_room) {
403                         syslog(LOG_DEBUG, "smtpclient: this message originated in <%s>", source_room);
404                 }
405                 StrBuf *NewInstr = NewStrBuf();
406                 StrBufAppendPrintf(NewInstr, "Content-type: " SPOOLMIME "\n\n");
407                 StrBufAppendPrintf(NewInstr, "msgid|%ld\n", msgid);
408                 StrBufAppendPrintf(NewInstr, "submitted|%ld\n", submitted);
409                 if (bounceto) {
410                         StrBufAppendPrintf(NewInstr, "bounceto|%s\n", bounceto);
411                 }
412                 if (envelope_from) {
413                         StrBufAppendPrintf(NewInstr, "envelope_from|%s\n", envelope_from);
414                 }
415                 for (i = 0; i < num_tokens(instr, '\n'); ++i) {
416                         extract_token(cfgline, instr, i, '\n', sizeof cfgline);
417                         if (!strncasecmp(cfgline, HKEY("remote|"))) {
418                                 char recp[SIZ];
419                                 int previous_result = extract_int(cfgline, 2);
420                                 if ((previous_result == 0) || (previous_result == 4)) {
421                                         int new_result = 421;
422                                         extract_token(recp, cfgline, 1, '|', sizeof recp);
423                                         new_result = smtp_attempt_delivery(msgid, recp, envelope_from, source_room, server_response);
424                                         syslog(LOG_DEBUG, "smtpclient: recp: <%s> , result: %d (%s)", recp, new_result, server_response);
425                                         if ((new_result / 100) == 2) {
426                                                 ++num_success;
427                                         }
428                                         else {
429                                                 if ((new_result / 100) == 5) {
430                                                         ++num_fail;
431                                                 }
432                                                 else {
433                                                         ++num_delayed;
434                                                 }
435                                                 StrBufAppendPrintf(NewInstr, "remote|%s|%ld|%ld (%s)\n", recp, (new_result / 100), new_result, server_response);
436                                         }
437                                 }
438                         }
439                 }
440
441                 StrBufAppendPrintf(NewInstr, "attempted|%ld\n", time(NULL));
442
443                 // All deliveries have now been attempted.  Now determine the disposition of this queue entry.
444
445                 time_t age = time(NULL) - submitted;
446                 syslog(LOG_DEBUG,
447                        "smtpclient: submission age: %ldd%ldh%ldm%lds",
448                        (age / 86400), ((age % 86400) / 3600), ((age % 3600) / 60), (age % 60));
449                 syslog(LOG_DEBUG, "smtpclient: num_success=%d , num_fail=%d , num_delayed=%d", num_success, num_fail, num_delayed);
450
451                 // If there are permanent fails on this attempt, deliver a bounce to the user.
452                 // The 5XX fails will be recorded in the rewritten queue, but they will be removed before the next attempt.
453                 if (num_fail > 0) {
454                         smtp_do_bounce(ChrPtr(NewInstr), SDB_BOUNCE_FATALS);
455                 }
456                 // If all deliveries have either succeeded or failed, we are finished with this queue entry.
457                 if (num_delayed == 0) {
458                         delete_this_queue = 1;
459                 }
460                 // If it's been more than five days, give up and tell the sender that delivery failed
461                 else if ((time(NULL) - submitted) > SMTP_DELIVER_FAIL) {
462                         smtp_do_bounce(ChrPtr(NewInstr), SDB_BOUNCE_ALL);
463                         delete_this_queue = 1;
464                 }
465                 // If it's been more than four hours but less than five days, warn the sender that delivery is delayed
466                 else if (((attempted - submitted) < SMTP_DELIVER_WARN) && ((time(NULL) - submitted) >= SMTP_DELIVER_WARN)) {
467                         smtp_do_bounce(ChrPtr(NewInstr), SDB_WARN);
468                 }
469
470                 if (delete_this_queue) {
471                         syslog(LOG_DEBUG, "smtpclient: %ld deleting", qmsgnum);
472                         deletes[0] = qmsgnum;
473                         deletes[1] = msgid;
474                         CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, deletes, 2, "");
475                         FreeStrBuf(&NewInstr);  // We have to free NewInstr here, no longer needed
476                 }
477                 else {
478                         // replace the old queue entry with the new one
479                         syslog(LOG_DEBUG, "smtpclient: %ld rewriting", qmsgnum);
480                         msg = convert_internet_message_buf(&NewInstr);  // This function will free NewInstr for us
481                         CtdlSubmitMsg(msg, NULL, SMTP_SPOOLOUT_ROOM);
482                         CM_Free(msg);
483                         CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, &qmsgnum, 1, "");
484                 }
485         }
486         else {
487                 syslog(LOG_DEBUG, "smtpclient: msg#%ld retry time not reached", qmsgnum);
488         }
489
490         if (bounceto != NULL) {
491                 free(bounceto);
492         }
493         if (envelope_from != NULL) {
494                 free(envelope_from);
495         }
496         if (source_room != NULL) {
497                 free(source_room);
498         }
499         free(instr);
500 }
501
502
503 // Callback for smtp_do_queue()
504 void smtp_add_msg(long msgnum, void *userdata) {
505         Array *smtp_queue = (Array *) userdata;
506         array_append(smtp_queue, &msgnum);
507 }
508
509
510 enum {
511         FULL_QUEUE_RUN,         // try to process the entire queue, including messages that have already been attempted
512         QUICK_QUEUE_RUN         // only process jobs in the queue that have not been tried yet
513 };
514
515
516 // Run through the queue sending out messages.
517 void smtp_do_queue(int type_of_queue_run) {
518         static int doing_smtpclient = 0;
519         int i = 0;
520
521         // This is a concurrency check to make sure only one smtpclient run is done at a time.
522         begin_critical_section(S_SMTPQUEUE);
523         if (doing_smtpclient) {
524                 end_critical_section(S_SMTPQUEUE);
525                 return;
526         }
527         doing_smtpclient = 1;
528         end_critical_section(S_SMTPQUEUE);
529
530         syslog(LOG_DEBUG, "smtpclient: start %s queue run , last_queue_job_processed=%ld , last_queue_job_submitted=%ld",
531                 (type_of_queue_run == QUICK_QUEUE_RUN ? "quick" : "full"),
532                 last_queue_job_processed, last_queue_job_submitted
533         );
534
535         if (CtdlGetRoom(&CC->room, SMTP_SPOOLOUT_ROOM) != 0) {
536                 syslog(LOG_WARNING, "smtpclient: cannot find room <%s>", SMTP_SPOOLOUT_ROOM);
537                 doing_smtpclient = 0;
538                 return;
539         }
540
541         // This array will hold the list of queue job messages
542         Array *smtp_queue = array_new(sizeof(long));
543         if (smtp_queue == NULL) {
544                 syslog(LOG_WARNING, "smtpclient: cannot allocate queue array");
545                 doing_smtpclient = 0;
546                 return;
547         }
548
549         // Put the queue in memory so we can close the db cursor
550         CtdlForEachMessage(
551                 (type_of_queue_run == QUICK_QUEUE_RUN ? MSGS_GT : MSGS_ALL),            // quick = new jobs; full = all jobs
552                 (type_of_queue_run == QUICK_QUEUE_RUN ? last_queue_job_processed : 0),  // quick = new jobs; full = all jobs
553                 NULL,
554                 SPOOLMIME,              // Searching for Content-type of SPOOLIME will give us only queue instruction messages
555                 NULL,
556                 smtp_add_msg,           // That's our callback function to add a job to the queue
557                 (void *)smtp_queue
558         );
559
560         // We are ready to run through the queue now.
561         syslog(LOG_DEBUG, "smtpclient: %d messages to be processed", array_len(smtp_queue));
562         for (i = 0; i < array_len(smtp_queue); ++i) {
563                 long m;
564                 memcpy(&m, array_get_element_at(smtp_queue, i), sizeof(long));
565                 smtp_process_one_msg(m);
566         }
567
568         array_free(smtp_queue);
569         last_queue_job_processed = last_queue_job_submitted;
570         doing_smtpclient = 0;
571         syslog(LOG_DEBUG, "smtpclient: end %s queue run , last_queue_job_processed=%ld , last_queue_job_submitted=%ld",
572                 (type_of_queue_run == QUICK_QUEUE_RUN ? "quick" : "full"),
573                 last_queue_job_processed, last_queue_job_submitted
574         );
575 }
576
577
578 // The "full" queue run goes through the entire queue, attempting delivery for newly submitted messages,
579 // retrying failed deliveries periodically, and handling undeliverable messages.
580 void smtp_do_queue_full(void) {
581         smtp_do_queue(FULL_QUEUE_RUN);
582 }
583
584
585 // The "quick" queue run only handles newly submitted messages, allowing them to be delivered immediately
586 // instead of waiting for the next "full" queue run.
587 void smtp_do_queue_quick(void) {
588         if (last_queue_job_submitted > last_queue_job_processed) {
589                 smtp_do_queue(QUICK_QUEUE_RUN);
590         }
591 }
592
593
594 // Initialization function, called from modules_init.c
595 char *ctdl_module_init_smtpclient(void) {
596         if (!threading) {
597                 CtdlRegisterMessageHook(smtp_aftersave, EVT_AFTERSAVE);
598                 CtdlRegisterSessionHook(smtp_do_queue_quick, EVT_HOUSE, PRIO_AGGR + 51);
599                 CtdlRegisterSessionHook(smtp_do_queue_full, EVT_TIMER, PRIO_AGGR + 51);
600                 smtp_init_spoolout();
601                 dkim_init();
602         }
603
604         // return our module id for the log
605         return "smtpclient";
606 }