citadel/modules/smtp/serv_smtpeventclient.c

   1 /*
   2  * This module is an SMTP and ESMTP implementation for the Citadel system.
   3  * It is compliant with all of the following:
   4  *
   5  * RFC  821 - Simple Mail Transfer Protocol
   6  * RFC  876 - Survey of SMTP Implementations
   7  * RFC 1047 - Duplicate messages and SMTP
   8  * RFC 1652 - 8 bit MIME
   9  * RFC 1869 - Extended Simple Mail Transfer Protocol
  10  * RFC 1870 - SMTP Service Extension for Message Size Declaration
  11  * RFC 2033 - Local Mail Transfer Protocol
  12  * RFC 2197 - SMTP Service Extension for Command Pipelining
  13  * RFC 2476 - Message Submission
  14  * RFC 2487 - SMTP Service Extension for Secure SMTP over TLS
  15  * RFC 2554 - SMTP Service Extension for Authentication
  16  * RFC 2821 - Simple Mail Transfer Protocol
  17  * RFC 2822 - Internet Message Format
  18  * RFC 2920 - SMTP Service Extension for Command Pipelining
  19  *
  20  * The VRFY and EXPN commands have been removed from this implementation
  21  * because nobody uses these commands anymore, except for spammers.
  22  *
  23  * Copyright (c) 1998-2012 by the citadel.org team
  24  *
  25  *  This program is open source software; you can redistribute it and/or modify
  26  *  it under the terms of the GNU General Public License version 3.
  27  *
  28  *
  29  *
  30  *  This program is distributed in the hope that it will be useful,
  31  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  32  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  33  *  GNU General Public License for more details.
  34  *
  35  *
  36  *
  37  *
  38  */
  39
  40 #include "sysdep.h"
  41 #include <stdlib.h>
  42 #include <unistd.h>
  43 #include <stdio.h>
  44 #include <termios.h>
  45 #include <fcntl.h>
  46 #include <signal.h>
  47 #include <pwd.h>
  48 #include <errno.h>
  49 #include <sys/types.h>
  50 #include <syslog.h>
  51
  52 #if TIME_WITH_SYS_TIME
  53 # include <sys/time.h>
  54 # include <time.h>
  55 #else
  56 # if HAVE_SYS_TIME_H
  57 #  include <sys/time.h>
  58 # else
  59 #  include <time.h>
  60 # endif
  61 #endif
  62 #include <sys/wait.h>
  63 #include <ctype.h>
  64 #include <string.h>
  65 #include <limits.h>
  66 #include <sys/socket.h>
  67 #include <netinet/in.h>
  68 #include <arpa/inet.h>
  69 #include <libcitadel.h>
  70 #include "citadel.h"
  71 #include "server.h"
  72 #include "citserver.h"
  73 #include "support.h"
  74 #include "config.h"
  75 #include "control.h"
  76 #include "user_ops.h"
  77 #include "database.h"
  78 #include "msgbase.h"
  79 #include "internet_addressing.h"
  80 #include "genstamp.h"
  81 #include "domain.h"
  82 #include "clientsocket.h"
  83 #include "locate_host.h"
  84 #include "citadel_dirs.h"
  85
  86 #include "ctdl_module.h"
  87
  88 #include "smtp_util.h"
  89 #include "event_client.h"
  90 #include "smtpqueue.h"
  91 #include "smtp_clienthandlers.h"
  92
  93 int SMTPClientDebugEnabled = 0;
  94 void DeleteSmtpOutMsg(void *v)
  95 {
  96         SmtpOutMsg *Msg = v;
  97         AsyncIO *IO = &Msg->IO;
  98         EV_syslog(LOG_DEBUG, "%s Exit\n", __FUNCTION__);
  99
 100         /* these are kept in our own space and free'd below */
 101         Msg->IO.ConnectMe = NULL;
 102
 103         ares_free_data(Msg->AllMX);
 104         if (Msg->HostLookup.VParsedDNSReply != NULL)
 105                 Msg->HostLookup.DNSReplyFree(Msg->HostLookup.VParsedDNSReply);
 106         FreeURL(&Msg->Relay);
 107         FreeStrBuf(&Msg->msgtext);
 108         FreeAsyncIOContents(&Msg->IO);
 109         memset (Msg, 0, sizeof(SmtpOutMsg)); /* just to be shure... */
 110         free(Msg);
 111 }
 112
 113 eNextState SMTP_C_Shutdown(AsyncIO *IO);
 114 eNextState SMTP_C_Timeout(AsyncIO *IO);
 115 eNextState SMTP_C_ConnFail(AsyncIO *IO);
 116 eNextState SMTP_C_DispatchReadDone(AsyncIO *IO);
 117 eNextState SMTP_C_DispatchWriteDone(AsyncIO *IO);
 118 eNextState SMTP_C_DNSFail(AsyncIO *IO);
 119 eNextState SMTP_C_Terminate(AsyncIO *IO);
 120 eNextState SMTP_C_TerminateDB(AsyncIO *IO);
 121 eReadState SMTP_C_ReadServerStatus(AsyncIO *IO);
 122
 123 eNextState mx_connect_ip(AsyncIO *IO);
 124 eNextState get_one_mx_host_ip(AsyncIO *IO);
 125
 126 /******************************************************************************
 127  * So, we're finished with sending (regardless of success or failure)         *
 128  * This Message might be referenced by several Queue-Items, if we're the last,*
 129  * we need to free the memory and send bounce messages (on terminal failure)  *
 130  * else we just free our SMTP-Message struct.                                 *
 131  ******************************************************************************/
 132 eNextState FinalizeMessageSend_DB(AsyncIO *IO)
 133 {
 134         const char *Status;
 135         SmtpOutMsg *Msg = IO->Data;
 136
 137         if (Msg->MyQEntry->Status == 2)
 138                 Status = "Delivery successful.";
 139         else if (Msg->MyQEntry->Status == 5)
 140                 Status = "Delivery failed permanently; giving up.";
 141         else
 142                 Status = "Delivery failed temporarily; will retry later.";
 143
 144         EVS_syslog(LOG_INFO,
 145                    "%s Time[%fs] Recipient <%s> @ <%s> (%s) Status message: %s\n",
 146                    Status,
 147                    Msg->IO.Now - Msg->IO.StartIO,
 148                    Msg->user,
 149                    Msg->node,
 150                    Msg->name,
 151                    ChrPtr(Msg->MyQEntry->StatusMessage));
 152
 153
 154         Msg->IDestructQueItem = DecreaseQReference(Msg->MyQItem);
 155
 156         Msg->nRemain = CountActiveQueueEntries(Msg->MyQItem);
 157
 158         if (Msg->MyQEntry->Active &&
 159             CheckQEntryIsBounce(Msg->MyQEntry))
 160         {
 161                 /* are we casue for a bounce mail? */
 162                 Msg->MyQItem->SendBounceMail |= (1<<Msg->MyQEntry->Status);
 163         }
 164
 165         if ((Msg->nRemain > 0) || Msg->IDestructQueItem)
 166                 Msg->QMsgData = SerializeQueueItem(Msg->MyQItem);
 167         else
 168                 Msg->QMsgData = NULL;
 169
 170         /*
 171          * Uncompleted delivery instructions remain, so delete the old
 172          * instructions and replace with the updated ones.
 173          */
 174         EVS_syslog(LOG_DEBUG, "%ld", Msg->MyQItem->QueMsgID);
 175         CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, &Msg->MyQItem->QueMsgID, 1, "");
 176         Msg->MyQItem->QueMsgID = -1;
 177
 178         if (Msg->IDestructQueItem)
 179                 smtpq_do_bounce(Msg->MyQItem, Msg->msgtext);
 180
 181         if (Msg->nRemain > 0)
 182         {
 183                 struct CtdlMessage *msg;
 184                 msg = malloc(sizeof(struct CtdlMessage));
 185                 memset(msg, 0, sizeof(struct CtdlMessage));
 186                 msg->cm_magic = CTDLMESSAGE_MAGIC;
 187                 msg->cm_anon_type = MES_NORMAL;
 188                 msg->cm_format_type = FMT_RFC822;
 189                 msg->cm_fields['M'] = SmashStrBuf(&Msg->QMsgData);
 190                 msg->cm_fields['U'] = strdup("QMSG");
 191                 Msg->MyQItem->QueMsgID =
 192                         CtdlSubmitMsg(msg, NULL, SMTP_SPOOLOUT_ROOM, QP_EADDR);
 193                 EVS_syslog(LOG_DEBUG, "%ld", Msg->MyQItem->QueMsgID);
 194                 CtdlFreeMessage(msg);
 195         }
 196         else {
 197                 CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM,
 198                                    &Msg->MyQItem->MessageID,
 199                                    1,
 200                                    "");
 201                 FreeStrBuf(&Msg->QMsgData);
 202         }
 203
 204         RemoveContext(Msg->IO.CitContext);
 205         return eAbort;
 206 }
 207
 208 eNextState Terminate(AsyncIO *IO)
 209 {
 210         SmtpOutMsg *Msg = IO->Data;
 211
 212         if (Msg->IDestructQueItem)
 213                 RemoveQItem(Msg->MyQItem);
 214
 215         DeleteSmtpOutMsg(Msg);
 216         return eAbort;
 217 }
 218 eNextState FinalizeMessageSend(SmtpOutMsg *Msg)
 219 {
 220         /* hand over to DB Queue */
 221         return QueueDBOperation(&Msg->IO, FinalizeMessageSend_DB);
 222 }
 223
 224 eNextState FailOneAttempt(AsyncIO *IO)
 225 {
 226         SmtpOutMsg *Msg = IO->Data;
 227
 228         if (Msg->MyQEntry->Status == 2)
 229                 return eAbort;
 230
 231         /*
 232          * possible ways here:
 233          * - connection timeout
 234          * - dns lookup failed
 235          */
 236         StopClientWatchers(IO, 1);
 237
 238         if (Msg->pCurrRelay != NULL)
 239                 Msg->pCurrRelay = Msg->pCurrRelay->Next;
 240         if ((Msg->pCurrRelay != NULL) &&
 241             !Msg->pCurrRelay->IsRelay &&
 242             Msg->MyQItem->HaveRelay)
 243         {
 244                 EVS_syslog(LOG_DEBUG, "%s Aborting; last relay failed.\n", __FUNCTION__);
 245                 return eAbort;
 246         }
 247
 248         if (Msg->pCurrRelay == NULL) {
 249                 EVS_syslog(LOG_DEBUG, "%s Aborting\n", __FUNCTION__);
 250                 return eAbort;
 251         }
 252         if (Msg->pCurrRelay->IsIP) {
 253                 EVS_syslog(LOG_DEBUG, "%s connecting IP\n", __FUNCTION__);
 254                 return mx_connect_ip(IO);
 255         }
 256         else {
 257                 EVS_syslog(LOG_DEBUG,
 258                            "%s resolving next MX Record\n",
 259                            __FUNCTION__);
 260                 return get_one_mx_host_ip(IO);
 261         }
 262 }
 263
 264
 265 void SetConnectStatus(AsyncIO *IO)
 266 {
 267         SmtpOutMsg *Msg = IO->Data;
 268         char buf[256];
 269         void *src;
 270
 271         buf[0] = '\0';
 272
 273         if (IO->ConnectMe->IPv6) {
 274                 src = &IO->ConnectMe->Addr.sin6_addr;
 275         }
 276         else {
 277                 struct sockaddr_in *addr;
 278
 279                 addr = (struct sockaddr_in *)&IO->ConnectMe->Addr;
 280                 src = &addr->sin_addr.s_addr;
 281         }
 282
 283         inet_ntop((IO->ConnectMe->IPv6)?AF_INET6:AF_INET,
 284                   src,
 285                   buf,
 286                   sizeof(buf));
 287
 288         if (Msg->mx_host == NULL)
 289                 Msg->mx_host = "<no MX-Record>";
 290
 291         EVS_syslog(LOG_INFO,
 292                   "connecting to %s [%s]:%d ...\n",
 293                   Msg->mx_host,
 294                   buf,
 295                   Msg->IO.ConnectMe->Port);
 296
 297         Msg->MyQEntry->Status = 4;
 298         StrBufPrintf(Msg->MyQEntry->StatusMessage,
 299                      "Timeout while connecting %s [%s]:%d ",
 300                      Msg->mx_host,
 301                      buf,
 302                      Msg->IO.ConnectMe->Port);
 303         Msg->IO.NextState = eConnect;
 304 }
 305
 306 /*****************************************************************************
 307  * So we connect our Relay IP here.                                          *
 308  *****************************************************************************/
 309 eNextState mx_connect_ip(AsyncIO *IO)
 310 {
 311         SmtpOutMsg *Msg = IO->Data;
 312
 313         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 314
 315         IO->ConnectMe = Msg->pCurrRelay;
 316         Msg->State = eConnectMX;
 317
 318         SetConnectStatus(IO);
 319
 320         return EvConnectSock(IO,
 321                              SMTP_C_ConnTimeout,
 322                              SMTP_C_ReadTimeouts[0],
 323                              1);
 324 }
 325
 326 eNextState get_one_mx_host_ip_done(AsyncIO *IO)
 327 {
 328         SmtpOutMsg *Msg = IO->Data;
 329         struct hostent *hostent;
 330
 331         IO->ConnectMe = Msg->pCurrRelay;
 332
 333         QueryCbDone(IO);
 334         EVS_syslog(LOG_DEBUG, "%s Time[%fs]\n",
 335                    __FUNCTION__,
 336                    IO->Now - IO->DNS.Start);
 337
 338         hostent = Msg->HostLookup.VParsedDNSReply;
 339         if ((Msg->HostLookup.DNSStatus == ARES_SUCCESS) &&
 340             (hostent != NULL) ) {
 341                 memset(&Msg->pCurrRelay->Addr, 0, sizeof(struct in6_addr));
 342                 if (Msg->pCurrRelay->IPv6) {
 343                         memcpy(&Msg->pCurrRelay->Addr.sin6_addr.s6_addr,
 344                                &hostent->h_addr_list[0],
 345                                sizeof(struct in6_addr));
 346
 347                         Msg->pCurrRelay->Addr.sin6_family =
 348                                 hostent->h_addrtype;
 349                         Msg->pCurrRelay->Addr.sin6_port =
 350                                 htons(Msg->IO.ConnectMe->Port);
 351                 }
 352                 else {
 353                         struct sockaddr_in *addr;
 354                         /*
 355                          * Bypass the ns lookup result like this:
 356                          * IO->Addr.sin_addr.s_addr = inet_addr("127.0.0.1");
 357                          * addr->sin_addr.s_addr =
 358                          *   htonl((uint32_t)&hostent->h_addr_list[0]);
 359                          */
 360
 361                         addr = (struct sockaddr_in*) &Msg->pCurrRelay->Addr;
 362
 363                         memcpy(&addr->sin_addr.s_addr,
 364                                hostent->h_addr_list[0],
 365                                sizeof(uint32_t));
 366
 367                         addr->sin_family = hostent->h_addrtype;
 368                         addr->sin_port   = htons(Msg->IO.ConnectMe->Port);
 369                 }
 370                 Msg->mx_host = Msg->pCurrRelay->Host;
 371                 if (Msg->HostLookup.VParsedDNSReply != NULL) {
 372                         Msg->HostLookup.DNSReplyFree(Msg->HostLookup.VParsedDNSReply);
 373                         Msg->HostLookup.VParsedDNSReply = NULL;
 374                 }
 375                 return mx_connect_ip(IO);
 376         }
 377         else {
 378                 if (Msg->HostLookup.VParsedDNSReply != NULL) {
 379                         Msg->HostLookup.DNSReplyFree(Msg->HostLookup.VParsedDNSReply);
 380                         Msg->HostLookup.VParsedDNSReply = NULL;
 381                 }
 382                 return FailOneAttempt(IO);
 383         }
 384 }
 385
 386 eNextState get_one_mx_host_ip(AsyncIO *IO)
 387 {
 388         SmtpOutMsg * Msg = IO->Data;
 389         /*
 390          * here we start with the lookup of one host. it might be...
 391          * - the relay host *sigh*
 392          * - the direct hostname if there was no mx record
 393          * - one of the mx'es
 394          */
 395
 396         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 397
 398         EVS_syslog(LOG_DEBUG,
 399                   "looking up %s-Record %s : %d ...\n",
 400                   (Msg->pCurrRelay->IPv6)? "aaaa": "a",
 401                   Msg->pCurrRelay->Host,
 402                   Msg->pCurrRelay->Port);
 403
 404         if (!QueueQuery((Msg->pCurrRelay->IPv6)? ns_t_aaaa : ns_t_a,
 405                         Msg->pCurrRelay->Host,
 406                         &Msg->IO,
 407                         &Msg->HostLookup,
 408                         get_one_mx_host_ip_done))
 409         {
 410                 Msg->MyQEntry->Status = 5;
 411                 StrBufPrintf(Msg->MyQEntry->StatusMessage,
 412                              "No MX hosts found for <%s>", Msg->node);
 413                 Msg->IO.NextState = eTerminateConnection;
 414                 return IO->NextState;
 415         }
 416         IO->NextState = eReadDNSReply;
 417         return IO->NextState;
 418 }
 419
 420
 421 /*****************************************************************************
 422  * here we try to find out about the MX records for our recipients.          *
 423  *****************************************************************************/
 424 eNextState smtp_resolve_mx_record_done(AsyncIO *IO)
 425 {
 426         SmtpOutMsg * Msg = IO->Data;
 427         ParsedURL **pp;
 428
 429         QueryCbDone(IO);
 430
 431         EVS_syslog(LOG_DEBUG, "%s Time[%fs]\n",
 432                    __FUNCTION__,
 433                    IO->Now - IO->DNS.Start);
 434
 435         pp = &Msg->Relay;
 436         while ((pp != NULL) && (*pp != NULL) && ((*pp)->Next != NULL))
 437                 pp = &(*pp)->Next;
 438
 439         if ((IO->DNS.Query->DNSStatus == ARES_SUCCESS) &&
 440             (IO->DNS.Query->VParsedDNSReply != NULL))
 441         { /* ok, we found mx records. */
 442
 443                 Msg->CurrMX
 444                         = Msg->AllMX
 445                         = IO->DNS.Query->VParsedDNSReply;
 446                 while (Msg->CurrMX) {
 447                         int i;
 448                         for (i = 0; i < 2; i++) {
 449                                 ParsedURL *p;
 450
 451                                 p = (ParsedURL*) malloc(sizeof(ParsedURL));
 452                                 memset(p, 0, sizeof(ParsedURL));
 453                                 p->Priority = Msg->CurrMX->priority;
 454                                 p->IsIP = 0;
 455                                 p->Port = DefaultMXPort;
 456                                 p->IPv6 = i == 1;
 457                                 p->Host = Msg->CurrMX->host;
 458                                 if (*pp == NULL)
 459                                         *pp = p;
 460                                 else {
 461                                         ParsedURL *ppp = *pp;
 462
 463                                         while ((ppp->Next != NULL) &&
 464                                                (ppp->Next->Priority <= p->Priority))
 465                                                ppp = ppp->Next;
 466                                         if ((ppp == *pp) &&
 467                                             (ppp->Priority > p->Priority)) {
 468                                                 p->Next = *pp;
 469                                                 *pp = p;
 470                                         }
 471                                         else {
 472                                                 p->Next = ppp->Next;
 473                                                 ppp->Next = p;
 474                                         }
 475                                 }
 476                         }
 477                         Msg->CurrMX    = Msg->CurrMX->next;
 478                 }
 479                 Msg->CXFlags   = Msg->CXFlags & F_HAVE_MX;
 480         }
 481         else { /* else fall back to the plain hostname */
 482                 int i;
 483                 for (i = 0; i < 2; i++) {
 484                         ParsedURL *p;
 485
 486                         p = (ParsedURL*) malloc(sizeof(ParsedURL));
 487                         memset(p, 0, sizeof(ParsedURL));
 488                         p->IsIP = 0;
 489                         p->Port = DefaultMXPort;
 490                         p->IPv6 = i == 1;
 491                         p->Host = Msg->node;
 492
 493                         *pp = p;
 494                         pp = &p->Next;
 495                 }
 496                 Msg->CXFlags   = Msg->CXFlags & F_DIRECT;
 497         }
 498         if (Msg->MyQItem->FallBackHost != NULL)
 499         {
 500                 Msg->MyQItem->FallBackHost->Next = *pp;
 501                 *pp = Msg->MyQItem->FallBackHost;
 502         }
 503         Msg->pCurrRelay = Msg->Relay;
 504         return get_one_mx_host_ip(IO);
 505 }
 506
 507 eNextState resolve_mx_records(AsyncIO *IO)
 508 {
 509         SmtpOutMsg * Msg = IO->Data;
 510
 511         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 512         /* start resolving MX records here. */
 513         if (!QueueQuery(ns_t_mx,
 514                         Msg->node,
 515                         &Msg->IO,
 516                         &Msg->MxLookup,
 517                         smtp_resolve_mx_record_done))
 518         {
 519                 Msg->MyQEntry->Status = 5;
 520                 StrBufPrintf(Msg->MyQEntry->StatusMessage,
 521                              "No MX hosts found for <%s>", Msg->node);
 522                 return IO->NextState;
 523         }
 524         Msg->IO.NextState = eReadDNSReply;
 525         return IO->NextState;
 526 }
 527
 528
 529
 530 /******************************************************************************
 531  *  so, we're going to start a SMTP delivery.  lets get it on.                *
 532  ******************************************************************************/
 533
 534 SmtpOutMsg *new_smtp_outmsg(OneQueItem *MyQItem,
 535                             MailQEntry *MyQEntry,
 536                             int MsgCount)
 537 {
 538         SmtpOutMsg * Msg;
 539
 540         Msg = (SmtpOutMsg *) malloc(sizeof(SmtpOutMsg));
 541         if (Msg == NULL)
 542                 return NULL;
 543         memset(Msg, 0, sizeof(SmtpOutMsg));
 544
 545         Msg->n                = MsgCount;
 546         Msg->MyQEntry         = MyQEntry;
 547         Msg->MyQItem          = MyQItem;
 548         Msg->pCurrRelay       = MyQItem->URL;
 549
 550         InitIOStruct(&Msg->IO,
 551                      Msg,
 552                      eReadMessage,
 553                      SMTP_C_ReadServerStatus,
 554                      SMTP_C_DNSFail,
 555                      SMTP_C_DispatchWriteDone,
 556                      SMTP_C_DispatchReadDone,
 557                      SMTP_C_Terminate,
 558                      SMTP_C_TerminateDB,
 559                      SMTP_C_ConnFail,
 560                      SMTP_C_Timeout,
 561                      SMTP_C_Shutdown);
 562
 563         Msg->IO.ErrMsg = Msg->MyQEntry->StatusMessage;
 564
 565         return Msg;
 566 }
 567
 568 void smtp_try_one_queue_entry(OneQueItem *MyQItem,
 569                               MailQEntry *MyQEntry,
 570                               StrBuf *MsgText,
 571                         /*KeepMsgText allows us to use MsgText as ours.*/
 572                               int KeepMsgText,
 573                               int MsgCount)
 574 {
 575         SmtpOutMsg *Msg;
 576
 577         SMTPC_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 578
 579         Msg = new_smtp_outmsg(MyQItem, MyQEntry, MsgCount);
 580         if (Msg == NULL) {
 581                 SMTPC_syslog(LOG_DEBUG, "%s Failed to alocate message context.\n", __FUNCTION__);
 582                 if (KeepMsgText)
 583                         FreeStrBuf (&MsgText);
 584                 return;
 585         }
 586         if (KeepMsgText) Msg->msgtext = MsgText;
 587         else             Msg->msgtext = NewStrBufDup(MsgText);
 588
 589         if (smtp_resolve_recipients(Msg)) {
 590
 591                 safestrncpy(
 592                         ((CitContext *)Msg->IO.CitContext)->cs_host,
 593                         Msg->node,
 594                         sizeof(((CitContext *)
 595                                 Msg->IO.CitContext)->cs_host));
 596
 597                 SMTPC_syslog(LOG_DEBUG, "Starting: [%ld] <%s> CC <%d> \n",
 598                              Msg->MyQItem->MessageID,
 599                              ChrPtr(Msg->MyQEntry->Recipient),
 600                              ((CitContext*)Msg->IO.CitContext)->cs_pid);
 601                 if (Msg->pCurrRelay == NULL)
 602                         QueueEventContext(&Msg->IO,
 603                                           resolve_mx_records);
 604                 else { /* oh... via relay host */
 605                         if (Msg->pCurrRelay->IsIP) {
 606                                 QueueEventContext(&Msg->IO,
 607                                                   mx_connect_ip);
 608                         }
 609                         else {
 610                                 /* uneducated admin has chosen to
 611                                    add DNS to the equation... */
 612                                 QueueEventContext(&Msg->IO,
 613                                                   get_one_mx_host_ip);
 614                         }
 615                 }
 616         }
 617         else {
 618                 /* No recipients? well fail then. */
 619                 if (Msg->MyQEntry != NULL) {
 620                         Msg->MyQEntry->Status = 5;
 621                         StrBufPlain(Msg->MyQEntry->StatusMessage,
 622                                     HKEY("Invalid Recipient!"));
 623                 }
 624                 FinalizeMessageSend_DB(&Msg->IO);
 625                 DeleteSmtpOutMsg(&Msg->IO);
 626         }
 627 }
 628
 629
 630
 631
 632
 633
 634 /*****************************************************************************/
 635 /*                     SMTP CLIENT DISPATCHER                                */
 636 /*****************************************************************************/
 637
 638 void SMTPSetTimeout(eNextState NextTCPState, SmtpOutMsg *Msg)
 639 {
 640         double Timeout = 0.0;
 641         AsyncIO *IO = &Msg->IO;
 642
 643         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 644
 645         switch (NextTCPState) {
 646         case eSendFile:
 647         case eSendReply:
 648         case eSendMore:
 649                 Timeout = SMTP_C_SendTimeouts[Msg->State];
 650                 if (Msg->State == eDATABody) {
 651                         /* if we're sending a huge message,
 652                          * we need more time.
 653                          */
 654                         Timeout += StrLength(Msg->msgtext) / 512;
 655                 }
 656                 break;
 657         case eReadMessage:
 658                 Timeout = SMTP_C_ReadTimeouts[Msg->State];
 659                 if (Msg->State == eDATATerminateBody) {
 660                         /*
 661                          * some mailservers take a nap before accepting
 662                          * the message content inspection and such.
 663                          */
 664                         Timeout += StrLength(Msg->msgtext) / 512;
 665                 }
 666                 break;
 667         case eSendDNSQuery:
 668         case eReadDNSReply:
 669         case eDBQuery:
 670         case eReadFile:
 671         case eReadMore:
 672         case eReadPayload:
 673         case eConnect:
 674         case eTerminateConnection:
 675         case eAbort:
 676                 return;
 677         }
 678         SetNextTimeout(&Msg->IO, Timeout);
 679 }
 680 eNextState SMTP_C_DispatchReadDone(AsyncIO *IO)
 681 {
 682         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 683         SmtpOutMsg *Msg = IO->Data;
 684         eNextState rc;
 685
 686         rc = ReadHandlers[Msg->State](Msg);
 687         if (rc != eAbort)
 688         {
 689                 Msg->State++;
 690                 SMTPSetTimeout(rc, Msg);
 691         }
 692         return rc;
 693 }
 694 eNextState SMTP_C_DispatchWriteDone(AsyncIO *IO)
 695 {
 696         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 697         SmtpOutMsg *Msg = IO->Data;
 698         eNextState rc;
 699
 700         rc = SendHandlers[Msg->State](Msg);
 701         SMTPSetTimeout(rc, Msg);
 702         return rc;
 703 }
 704
 705
 706 /*****************************************************************************/
 707 /*                     SMTP CLIENT ERROR CATCHERS                            */
 708 /*****************************************************************************/
 709 eNextState SMTP_C_Terminate(AsyncIO *IO)
 710 {
 711         SmtpOutMsg *Msg = IO->Data;
 712
 713         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 714         return FinalizeMessageSend(Msg);
 715 }
 716 eNextState SMTP_C_TerminateDB(AsyncIO *IO)
 717 {
 718         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 719         return Terminate(IO);
 720 }
 721 eNextState SMTP_C_Timeout(AsyncIO *IO)
 722 {
 723         SmtpOutMsg *Msg = IO->Data;
 724
 725         Msg->MyQEntry->Status = 4;
 726         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 727         StrBufPlain(IO->ErrMsg, CKEY(ReadErrors[Msg->State]));
 728         if (Msg->State > eRCPT)
 729                 return eAbort;
 730         else
 731                 return FailOneAttempt(IO);
 732 }
 733 eNextState SMTP_C_ConnFail(AsyncIO *IO)
 734 {
 735         SmtpOutMsg *Msg = IO->Data;
 736
 737         Msg->MyQEntry->Status = 4;
 738         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 739         StrBufPlain(IO->ErrMsg, CKEY(ReadErrors[Msg->State]));
 740         return FailOneAttempt(IO);
 741 }
 742 eNextState SMTP_C_DNSFail(AsyncIO *IO)
 743 {
 744         SmtpOutMsg *Msg = IO->Data;
 745         Msg->MyQEntry->Status = 4;
 746         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 747         return FailOneAttempt(IO);
 748 }
 749 eNextState SMTP_C_Shutdown(AsyncIO *IO)
 750 {
 751         EVS_syslog(LOG_DEBUG, "%s\n", __FUNCTION__);
 752         SmtpOutMsg *Msg = IO->Data;
 753
 754         switch (IO->NextState) {
 755         case eSendDNSQuery:
 756         case eReadDNSReply:
 757
 758                 /* todo: abort c-ares */
 759         case eConnect:
 760         case eSendReply:
 761         case eSendMore:
 762         case eSendFile:
 763         case eReadMessage:
 764         case eReadMore:
 765         case eReadPayload:
 766         case eReadFile:
 767                 StopClientWatchers(IO, 1);
 768                 break;
 769         case eDBQuery:
 770
 771                 break;
 772         case eTerminateConnection:
 773         case eAbort:
 774                 break;
 775         }
 776         Msg->MyQEntry->Status = 3;
 777         StrBufPlain(Msg->MyQEntry->StatusMessage,
 778                     HKEY("server shutdown during message submit."));
 779         return FinalizeMessageSend(Msg);
 780 }
 781
 782
 783 /**
 784  * @brief lineread Handler;
 785  * understands when to read more SMTP lines, and when this is a one-lined reply.
 786  */
 787 eReadState SMTP_C_ReadServerStatus(AsyncIO *IO)
 788 {
 789         eReadState Finished = eBufferNotEmpty;
 790
 791         while (Finished == eBufferNotEmpty) {
 792                 Finished = StrBufChunkSipLine(IO->IOBuf, &IO->RecvBuf);
 793
 794                 switch (Finished) {
 795                 case eMustReadMore: /// read new from socket...
 796                         return Finished;
 797                         break;
 798                 case eBufferNotEmpty: /* shouldn't happen... */
 799                 case eReadSuccess: /// done for now...
 800                         if (StrLength(IO->IOBuf) < 4)
 801                                 continue;
 802                         if (ChrPtr(IO->IOBuf)[3] == '-')
 803                                 Finished = eBufferNotEmpty;
 804                         else
 805                                 return Finished;
 806                         break;
 807                 case eReadFail: /// WHUT?
 808                         ///todo: shut down!
 809                         break;
 810                 }
 811         }
 812         return Finished;
 813 }
 814
 815 void LogDebugEnableSMTPClient(const int n)
 816 {
 817         SMTPClientDebugEnabled = n;
 818 }
 819
 820 CTDL_MODULE_INIT(smtp_eventclient)
 821 {
 822         if (!threading)
 823                 CtdlRegisterDebugFlagHook(HKEY("smtpeventclient"), LogDebugEnableSMTPClient, &SMTPClientDebugEnabled);
 824         return "smtpeventclient";
 825 }