+++ /dev/null
-// Transmit outbound SMTP mail to the big wide world of the Internet
-//
-// This is the new, exciting, clever version that makes libcurl do all the work :)
-//
-// Copyright (c) 1997-2022 by the citadel.org team
-//
-// This program is open source software; you can redistribute it and/or
-// modify it under the terms of the GNU General Public License as published
-// by the Free Software Foundation; either version 3 of the License, or
-// (at your option) any later version.
-//
-// This program is distributed in the hope that it will be useful,
-// but WITHOUT ANY WARRANTY; without even the implied warranty of
-// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-// GNU General Public License for more details.
-
-#include <stdlib.h>
-#include <unistd.h>
-#include <stdio.h>
-#include <sysconfig.h>
-#include <time.h>
-#include <ctype.h>
-#include <string.h>
-#include <errno.h>
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <libcitadel.h>
-#include <curl/curl.h>
-#include "citadel.h"
-#include "server.h"
-#include "citserver.h"
-#include "support.h"
-#include "config.h"
-#include "ctdl_module.h"
-#include "clientsocket.h"
-#include "msgbase.h"
-#include "domain.h"
-#include "internet_addressing.h"
-#include "citadel_dirs.h"
-#include "modules/smtp/smtp_util.h"
-
-struct smtpmsgsrc { // Data passed in and out of libcurl for message upload
- StrBuf *TheMessage;
- int bytes_total;
- int bytes_sent;
-};
-
-static int doing_smtpclient = 0;
-long *smtpq = NULL; // array of msgnums containing queue instructions
-int smtpq_count = 0; // number of queue messages in smtpq
-int smtpq_alloc = 0; // current allocation size for smtpq
-
-
-// Initialize the SMTP outbound queue
-void smtp_init_spoolout(void) {
- struct ctdlroom qrbuf;
-
- // Create the room. This will silently fail if the room already
- // exists, and that's perfectly ok, because we want it to exist.
- CtdlCreateRoom(SMTP_SPOOLOUT_ROOM, 3, "", 0, 1, 0, VIEW_QUEUE);
-
- // Make sure it's set to be a "system room" so it doesn't show up
- // in the <K>nown rooms list for administrators.
- if (CtdlGetRoomLock(&qrbuf, SMTP_SPOOLOUT_ROOM) == 0) {
- qrbuf.QRflags2 |= QR2_SYSTEM;
- CtdlPutRoomLock(&qrbuf);
- }
-}
-
-
-// For internet mail, generate delivery instructions.
-// Yes, this is recursive. Deal with it. Infinite recursion does
-// not happen because the delivery instructions message does not
-// contain a recipient.
-int smtp_aftersave(struct CtdlMessage *msg, struct recptypes *recps) {
- if ((recps != NULL) && (recps->num_internet > 0)) {
- struct CtdlMessage *imsg = NULL;
- char recipient[SIZ];
- StrBuf *SpoolMsg = NewStrBuf();
- long nTokens;
- int i;
-
- syslog(LOG_DEBUG, "smtpclient: generating delivery instructions");
-
- StrBufPrintf(SpoolMsg,
- "Content-type: " SPOOLMIME "\n"
- "\n"
- "msgid|%s\n"
- "submitted|%ld\n" "bounceto|%s\n", msg->cm_fields[eVltMsgNum], (long) time(NULL), recps->bounce_to);
-
- if (recps->envelope_from != NULL) {
- StrBufAppendBufPlain(SpoolMsg, HKEY("envelope_from|"), 0);
- StrBufAppendBufPlain(SpoolMsg, recps->envelope_from, -1, 0);
- StrBufAppendBufPlain(SpoolMsg, HKEY("\n"), 0);
- }
- if (recps->sending_room != NULL) {
- StrBufAppendBufPlain(SpoolMsg, HKEY("source_room|"), 0);
- StrBufAppendBufPlain(SpoolMsg, recps->sending_room, -1, 0);
- StrBufAppendBufPlain(SpoolMsg, HKEY("\n"), 0);
- }
-
- nTokens = num_tokens(recps->recp_internet, '|');
- for (i = 0; i < nTokens; i++) {
- long len;
- len = extract_token(recipient, recps->recp_internet, i, '|', sizeof recipient);
- if (len > 0) {
- StrBufAppendBufPlain(SpoolMsg, HKEY("remote|"), 0);
- StrBufAppendBufPlain(SpoolMsg, recipient, len, 0);
- StrBufAppendBufPlain(SpoolMsg, HKEY("|0||\n"), 0);
- }
- }
-
- imsg = malloc(sizeof(struct CtdlMessage));
- memset(imsg, 0, sizeof(struct CtdlMessage));
- imsg->cm_magic = CTDLMESSAGE_MAGIC;
- imsg->cm_anon_type = MES_NORMAL;
- imsg->cm_format_type = FMT_RFC822;
- CM_SetField(imsg, eMsgSubject, HKEY("QMSG"));
- CM_SetField(imsg, eAuthor, HKEY("Citadel"));
- CM_SetField(imsg, eJournal, HKEY("do not journal"));
- CM_SetAsFieldSB(imsg, eMesageText, &SpoolMsg);
- CtdlSubmitMsg(imsg, NULL, SMTP_SPOOLOUT_ROOM);
- CM_Free(imsg);
- }
- return 0;
-}
-
-
-// Callback for smtp_attempt_delivery() to supply libcurl with upload data.
-static size_t upload_source(void *ptr, size_t size, size_t nmemb, void *userp) {
- struct smtpmsgsrc *s = (struct smtpmsgsrc *) userp;
- int sendbytes = 0;
- const char *send_this = NULL;
-
- sendbytes = (size * nmemb);
-
- if (s->bytes_sent >= s->bytes_total) {
- return (0); // no data remaining; we are done
- }
-
- if (sendbytes > (s->bytes_total - s->bytes_sent)) {
- sendbytes = s->bytes_total - s->bytes_sent; // can't send more than we have
- }
-
- send_this = ChrPtr(s->TheMessage);
- send_this += s->bytes_sent; // start where we last left off
-
- memcpy(ptr, send_this, sendbytes);
- s->bytes_sent += sendbytes;
- return(sendbytes); // return the number of bytes _actually_ copied
-}
-
-
-// The libcurl API doesn't provide a way to capture the actual SMTP result message returned
-// by the remote server. This is an ugly way to extract it, by capturing debug data from
-// the library and filtering on the lines we want.
-int ctdl_libcurl_smtp_debug_callback(CURL *handle, curl_infotype type, char *data, size_t size, void *userptr) {
- if (type != CURLINFO_HEADER_IN)
- return 0;
- if (!userptr)
- return 0;
- char *debugbuf = (char *) userptr;
-
- int len = strlen(debugbuf);
- if (len + size > SIZ)
- return 0;
-
- memcpy(&debugbuf[len], data, size);
- debugbuf[len + size] = 0;
- return 0;
-}
-
-
-// Go through the debug output of an SMTP transaction, and boil it down to just the final success or error response message.
-void trim_response(long response_code, char *response) {
- if ((response_code < 100) || (response_code > 999) || (IsEmptyStr(response))) {
- return;
- }
-
- char *t = malloc(strlen(response));
- if (!t) {
- return;
- }
- t[0] = 0;
-
- char *p;
- for (p = response; *p != 0; ++p) {
- if ( (*p != '\n') && (!isprint(*p)) ) { // expunge any nonprintables except for newlines
- *p = ' ';
- }
- }
-
- char response_code_str[4];
- snprintf(response_code_str, sizeof response_code_str, "%ld", response_code);
- char *respstart = strstr(response, response_code_str);
- if (respstart == NULL) { // If we have a response code but no response text,
- strcpy(response, smtpstatus(response_code)); // use one of our canned messages.
- return;
- }
- strcpy(response, respstart);
-
- p = strstr(response, "\n");
- if (p != NULL) {
- *p = 0;
- }
-}
-
-
-// Attempt a delivery to one recipient.
-// Returns a three-digit SMTP status code.
-int smtp_attempt_delivery(long msgid, char *recp, char *envelope_from, char *source_room, char *response) {
- struct smtpmsgsrc s;
- char *fromaddr = NULL;
- CURL *curl;
- CURLcode res = CURLE_OK;
- struct curl_slist *recipients = NULL;
- long response_code = 421;
- int num_mx = 0;
- char mxes[SIZ];
- char user[1024];
- char node[1024];
- char name[1024];
- char try_this_mx[256];
- char smtp_url[512];
- int i;
-
- syslog(LOG_DEBUG, "smtpclient: smtp_attempt_delivery(%ld, %s)", msgid, recp);
-
- process_rfc822_addr(recp, user, node, name); // split recipient address into username, hostname, displayname
- num_mx = getmx(mxes, node);
- if (num_mx < 1) {
- return (421);
- }
-
- CC->redirect_buffer = NewStrBufPlain(NULL, SIZ);
- if (!IsEmptyStr(source_room)) {
- // If we have a source room, it's probably a mailing list message; generate an unsubscribe header
- char esc_room[ROOMNAMELEN*2];
- char esc_email[1024];
- urlesc(esc_room, sizeof esc_room, source_room);
- urlesc(esc_email, sizeof esc_email, recp);
- cprintf("List-Unsubscribe: <http://%s/listsub?cmd=unsubscribe&room=%s&email=%s>\r\n",
- CtdlGetConfigStr("c_fqdn"),
- esc_room,
- esc_email
- );
- }
- CtdlOutputMsg(msgid, MT_RFC822, HEADERS_ALL, 0, 1, NULL, 0, NULL, &fromaddr, NULL);
- s.TheMessage = CC->redirect_buffer;
- s.bytes_total = StrLength(CC->redirect_buffer);
- s.bytes_sent = 0;
- CC->redirect_buffer = NULL;
- response_code = 421;
- // keep trying MXes until one works or we run out
- for (i = 0; ((i < num_mx) && ((response_code / 100) == 4)); ++i) {
- response_code = 421; // default 421 makes non-protocol errors transient
- s.bytes_sent = 0; // rewind our buffer in case we try multiple MXes
-
- curl = curl_easy_init();
- if (curl) {
- response[0] = 0;
-
- if (!IsEmptyStr(envelope_from)) {
- curl_easy_setopt(curl, CURLOPT_MAIL_FROM, envelope_from);
- }
- else {
- curl_easy_setopt(curl, CURLOPT_MAIL_FROM, fromaddr);
- }
-
- recipients = curl_slist_append(recipients, recp);
- curl_easy_setopt(curl, CURLOPT_MAIL_RCPT, recipients);
- curl_easy_setopt(curl, CURLOPT_READFUNCTION, upload_source);
- curl_easy_setopt(curl, CURLOPT_READDATA, &s);
- curl_easy_setopt(curl, CURLOPT_UPLOAD, 1); // tell libcurl we are uploading
- curl_easy_setopt(curl, CURLOPT_TIMEOUT, 20L); // Time out after 20 seconds
- if (CtdlGetConfigInt("c_smtpclient_disable_starttls") == 0) {
- curl_easy_setopt(curl, CURLOPT_USE_SSL, CURLUSESSL_TRY); // Attempt STARTTLS if offered
- }
- curl_easy_setopt(curl, CURLOPT_SSL_VERIFYPEER, 0L);
- curl_easy_setopt(curl, CURLOPT_SSL_VERIFYHOST, 0L);
- curl_easy_setopt(curl, CURLOPT_DEBUGFUNCTION, ctdl_libcurl_smtp_debug_callback);
- curl_easy_setopt(curl, CURLOPT_DEBUGDATA, (void *) response);
- curl_easy_setopt(curl, CURLOPT_VERBOSE, 1L);
-
- // Construct an SMTP URL in the form of:
- // smtp[s]://target_host/source_host
- // This looks weird but libcurl uses that last part to set our name for EHLO or HELO.
- // We check for "smtp://" and "smtps://" because the admin may have put those prefixes in a smart-host entry.
- // If there is no prefix we add "smtp://"
- extract_token(try_this_mx, mxes, i, '|', (sizeof try_this_mx - 7));
- snprintf(smtp_url, sizeof smtp_url,
- "%s%s/%s",
- (((!strncasecmp(try_this_mx, HKEY("smtp://")))
- || (!strncasecmp(try_this_mx, HKEY("smtps://")))) ? "" : "smtp://"),
- try_this_mx, CtdlGetConfigStr("c_fqdn")
- );
- curl_easy_setopt(curl, CURLOPT_URL, smtp_url);
- syslog(LOG_DEBUG, "smtpclient: trying MX %d of %d <%s>", i+1, num_mx, smtp_url); // send the message
- res = curl_easy_perform(curl);
- curl_easy_getinfo(curl, CURLINFO_RESPONSE_CODE, &response_code);
- syslog(LOG_DEBUG,
- "smtpclient: libcurl returned %d (%s) , SMTP response %ld",
- res, curl_easy_strerror(res), response_code
- );
-
- if ((res != CURLE_OK) && (response_code == 0)) { // check for errors
- response_code = 421;
- }
-
- curl_slist_free_all(recipients);
- recipients = NULL; // this gets reused; avoid double-free
- curl_easy_cleanup(curl);
- curl = NULL; // this gets reused; avoid double-free
-
- // Trim the error message buffer down to just the actual message
- trim_response(response_code, response);
- }
- }
-
- FreeStrBuf(&s.TheMessage);
- if (fromaddr) {
- free(fromaddr);
- }
- return ((int) response_code);
-}
-
-
-// Process one outbound message.
-void smtp_process_one_msg(long qmsgnum) {
- struct CtdlMessage *msg = NULL;
- char *instr = NULL;
- int i;
- int num_success = 0;
- int num_fail = 0;
- int num_delayed = 0;
- long deletes[2];
- int delete_this_queue = 0;
- char server_response[SIZ];
-
- msg = CtdlFetchMessage(qmsgnum, 1);
- if (msg == NULL) {
- syslog(LOG_WARNING, "smtpclient: %ld does not exist", qmsgnum);
- return;
- }
-
- instr = msg->cm_fields[eMesageText];
- msg->cm_fields[eMesageText] = NULL;
- CM_Free(msg);
-
- // if the queue message has any CRLF's convert them to LF's
- char *crlf = NULL;
- while (crlf = strstr(instr, "\r\n"), crlf != NULL) {
- strcpy(crlf, crlf + 1);
- }
-
- // Strip out the headers and we are now left with just the instructions.
- char *soi = strstr(instr, "\n\n");
- if (soi) {
- strcpy(instr, soi + 2);
- }
-
- long msgid = 0;
- time_t submitted = time(NULL);
- time_t attempted = 0;
- char *bounceto = NULL;
- char *envelope_from = NULL;
- char *source_room = NULL;
-
- char cfgline[SIZ];
- for (i = 0; i < num_tokens(instr, '\n'); ++i) {
- extract_token(cfgline, instr, i, '\n', sizeof cfgline);
- if (!strncasecmp(cfgline, HKEY("msgid|")))
- msgid = atol(&cfgline[6]);
- if (!strncasecmp(cfgline, HKEY("submitted|")))
- submitted = atol(&cfgline[10]);
- if (!strncasecmp(cfgline, HKEY("attempted|")))
- attempted = atol(&cfgline[10]);
- if (!strncasecmp(cfgline, HKEY("bounceto|")))
- bounceto = strdup(&cfgline[9]);
- if (!strncasecmp(cfgline, HKEY("envelope_from|")))
- envelope_from = strdup(&cfgline[14]);
- if (!strncasecmp(cfgline, HKEY("source_room|")))
- source_room = strdup(&cfgline[12]);
- }
-
- int should_try_now = 0;
- if (attempted < submitted) { // If no attempts have been made yet, try now
- should_try_now = 1;
- }
- else if ((attempted - submitted) <= 14400) {
- if ((time(NULL) - attempted) > 1800) { // First four hours, retry every 30 minutes
- should_try_now = 1;
- }
- }
- else {
- if ((time(NULL) - attempted) > 14400) { // After that, retry once every 4 hours
- should_try_now = 1;
- }
- }
-
- if (should_try_now) {
- syslog(LOG_DEBUG, "smtpclient: attempting delivery of message <%ld> now", qmsgnum);
- if (source_room) {
- syslog(LOG_DEBUG, "smtpclient: this message originated in <%s>", source_room);
- }
- StrBuf *NewInstr = NewStrBuf();
- StrBufAppendPrintf(NewInstr, "Content-type: " SPOOLMIME "\n\n");
- StrBufAppendPrintf(NewInstr, "msgid|%ld\n", msgid);
- StrBufAppendPrintf(NewInstr, "submitted|%ld\n", submitted);
- if (bounceto) {
- StrBufAppendPrintf(NewInstr, "bounceto|%s\n", bounceto);
- }
- if (envelope_from) {
- StrBufAppendPrintf(NewInstr, "envelope_from|%s\n", envelope_from);
- }
- for (i = 0; i < num_tokens(instr, '\n'); ++i) {
- extract_token(cfgline, instr, i, '\n', sizeof cfgline);
- if (!strncasecmp(cfgline, HKEY("remote|"))) {
- char recp[SIZ];
- int previous_result = extract_int(cfgline, 2);
- if ((previous_result == 0)
- || (previous_result == 4)) {
- int new_result = 421;
- extract_token(recp, cfgline, 1, '|', sizeof recp);
- new_result = smtp_attempt_delivery(msgid, recp, envelope_from, source_room, server_response);
- syslog(LOG_DEBUG, "smtpclient: recp: <%s> , result: %d (%s)", recp, new_result, server_response);
- if ((new_result / 100) == 2) {
- ++num_success;
- }
- else {
- if ((new_result / 100) == 5) {
- ++num_fail;
- }
- else {
- ++num_delayed;
- }
- StrBufAppendPrintf
- (NewInstr,
- "remote|%s|%ld|%ld (%s)\n",
- recp, (new_result / 100), new_result, server_response);
- }
- }
- }
- }
-
- StrBufAppendPrintf(NewInstr, "attempted|%ld\n", time(NULL));
-
- // All deliveries have now been attempted. Now determine the disposition of this queue entry.
-
- time_t age = time(NULL) - submitted;
- syslog(LOG_DEBUG,
- "smtpclient: submission age: %ldd%ldh%ldm%lds",
- (age / 86400), ((age % 86400) / 3600), ((age % 3600) / 60), (age % 60));
- syslog(LOG_DEBUG, "smtpclient: num_success=%d , num_fail=%d , num_delayed=%d", num_success, num_fail, num_delayed);
-
- // If there are permanent fails on this attempt, deliver a bounce to the user.
- // The 5XX fails will be recorded in the rewritten queue, but they will be removed before the next attempt.
- if (num_fail > 0) {
- smtp_do_bounce(ChrPtr(NewInstr), SDB_BOUNCE_FATALS);
- }
- // If all deliveries have either succeeded or failed, we are finished with this queue entry.
- if (num_delayed == 0) {
- delete_this_queue = 1;
- }
- // If it's been more than five days, give up and tell the sender that delivery failed
- else if ((time(NULL) - submitted) > SMTP_DELIVER_FAIL) {
- smtp_do_bounce(ChrPtr(NewInstr), SDB_BOUNCE_ALL);
- delete_this_queue = 1;
- }
- // If it's been more than four hours but less than five days, warn the sender that delivery is delayed
- else if (((attempted - submitted) < SMTP_DELIVER_WARN)
- && ((time(NULL) - submitted) >= SMTP_DELIVER_WARN)) {
- smtp_do_bounce(ChrPtr(NewInstr), SDB_WARN);
- }
-
- if (delete_this_queue) {
- syslog(LOG_DEBUG, "smtpclient: %ld deleting", qmsgnum);
- deletes[0] = qmsgnum;
- deletes[1] = msgid;
- CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, deletes, 2, "");
- FreeStrBuf(&NewInstr); // We have to free NewInstr here, no longer needed
- }
- else {
- // replace the old queue entry with the new one
- syslog(LOG_DEBUG, "smtpclient: %ld rewriting", qmsgnum);
- msg = convert_internet_message_buf(&NewInstr); // This function will free NewInstr for us
- CtdlSubmitMsg(msg, NULL, SMTP_SPOOLOUT_ROOM);
- CM_Free(msg);
- CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, &qmsgnum, 1, "");
- }
- }
- else {
- syslog(LOG_DEBUG, "smtpclient: %ld retry time not reached", qmsgnum);
- }
-
- if (bounceto != NULL) {
- free(bounceto);
- }
- if (envelope_from != NULL) {
- free(envelope_from);
- }
- if (source_room != NULL) {
- free(source_room);
- }
- free(instr);
-}
-
-
-// Callback for smtp_do_queue()
-void smtp_add_msg(long msgnum, void *userdata) {
-
- if (smtpq == NULL) {
- smtpq_count = 0;
- smtpq_alloc = 100;
- smtpq = malloc(smtpq_alloc * sizeof(long));
- }
-
- if (smtpq_alloc >= smtpq_count) {
- smtpq_alloc += 100;
- smtpq = realloc(smtpq, (smtpq_alloc * sizeof(long)));
- }
-
- smtpq[smtpq_count++] = msgnum;
-}
-
-
-// Run through the queue sending out messages.
-void smtp_do_queue(void) {
- int i = 0;
-
- // This is a simple concurrency check to make sure only one smtpclient
- // run is done at a time. We could do this with a mutex, but since we
- // don't really require extremely fine granularity here, we'll do it
- // with a static variable instead.
- if (doing_smtpclient) {
- return;
- }
- doing_smtpclient = 1;
-
- syslog(LOG_DEBUG, "smtpclient: start queue run");
-
- if (CtdlGetRoom(&CC->room, SMTP_SPOOLOUT_ROOM) != 0) {
- syslog(LOG_WARNING, "Cannot find room <%s>", SMTP_SPOOLOUT_ROOM);
- doing_smtpclient = 0;
- return;
- }
- // Put the queue in memory so we can close the db cursor
- CtdlForEachMessage(MSGS_ALL, 0L, NULL, SPOOLMIME, NULL, smtp_add_msg, NULL);
-
- // We are ready to run through the queue now.
- for (i = 0; i < smtpq_count; ++i) {
- smtp_process_one_msg(smtpq[i]);
- }
-
- smtpq_count = 0; // don't free it, we will use this memory on the next run
- doing_smtpclient = 0;
- syslog(LOG_DEBUG, "smtpclient: end queue run");
-}
-
-
-// Module entry point
-CTDL_MODULE_INIT(smtpclient)
-{
- if (!threading) {
- CtdlRegisterMessageHook(smtp_aftersave, EVT_AFTERSAVE);
- CtdlRegisterSessionHook(smtp_do_queue, EVT_TIMER, PRIO_AGGR + 51);
- smtp_init_spoolout();
- }
-
- // return our module id for the log
- return "smtpclient";
-}
projects / citadel.git / blobdiff