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) 1998-2009 by the citadel.org team
  24  *
  25  *  This program is free software; you can redistribute it and/or modify
  26  *  it under the terms of the GNU General Public License as published by
  27  *  the Free Software Foundation; either version 3 of the License, or
  28  *  (at your option) any later version.
  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  *  You should have received a copy of the GNU General Public License
  36  *  along with this program; if not, write to the Free Software
  37  *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  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 const unsigned short DefaultMXPort = 25;
  94 void DeleteSmtpOutMsg(void *v)
  95 {
  96         SmtpOutMsg *Msg = v;
  97         AsyncIO *IO = &Msg->IO;
  98         EV_syslog(LOG_DEBUG, "SMTP: %s Aborting\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 eReadState SMTP_C_ReadServerStatus(AsyncIO *IO);
 121
 122 eNextState mx_connect_ip(AsyncIO *IO);
 123 eNextState get_one_mx_host_ip(AsyncIO *IO);
 124
 125 /******************************************************************************
 126  * So, we're finished with sending (regardless of success or failure)         *
 127  * This Message might be referenced by several Queue-Items, if we're the last,*
 128  * we need to free the memory and send bounce messages (on terminal failure)  *
 129  * else we just free our SMTP-Message struct.                                 *
 130  ******************************************************************************/
 131 void FinalizeMessageSend(SmtpOutMsg *Msg)
 132 {
 133         int IDestructQueItem;
 134         int nRemain;
 135         StrBuf *MsgData;
 136         AsyncIO *IO = &Msg->IO;
 137
 138         IDestructQueItem = DecreaseQReference(Msg->MyQItem);
 139
 140         nRemain = CountActiveQueueEntries(Msg->MyQItem);
 141
 142         if ((nRemain > 0) || IDestructQueItem)
 143                 MsgData = SerializeQueueItem(Msg->MyQItem);
 144         else
 145                 MsgData = NULL;
 146
 147         /*
 148          * Uncompleted delivery instructions remain, so delete the old
 149          * instructions and replace with the updated ones.
 150          */
 151         EVS_syslog(LOG_DEBUG, "SMTPQD: %ld", Msg->MyQItem->QueMsgID);
 152         CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM, &Msg->MyQItem->QueMsgID, 1, "");
 153
 154         if (IDestructQueItem)
 155                 smtpq_do_bounce(Msg->MyQItem,Msg->msgtext);
 156
 157         if (nRemain > 0)
 158         {
 159                 struct CtdlMessage *msg;
 160                 msg = malloc(sizeof(struct CtdlMessage));
 161                 memset(msg, 0, sizeof(struct CtdlMessage));
 162                 msg->cm_magic = CTDLMESSAGE_MAGIC;
 163                 msg->cm_anon_type = MES_NORMAL;
 164                 msg->cm_format_type = FMT_RFC822;
 165                 msg->cm_fields['M'] = SmashStrBuf(&MsgData);
 166                 Msg->MyQItem->QueMsgID =
 167                         CtdlSubmitMsg(msg, NULL, SMTP_SPOOLOUT_ROOM, QP_EADDR);
 168                 EVS_syslog(LOG_DEBUG, "SMTPQ: %ld", Msg->MyQItem->QueMsgID);
 169                 CtdlFreeMessage(msg);
 170         }
 171         else {
 172                 CtdlDeleteMessages(SMTP_SPOOLOUT_ROOM,
 173                                    &Msg->MyQItem->MessageID,
 174                                    1,
 175                                    "");
 176                 FreeStrBuf(&MsgData);
 177         }
 178         RemoveContext(Msg->IO.CitContext);
 179         if (IDestructQueItem)
 180                 RemoveQItem(Msg->MyQItem);
 181         DeleteSmtpOutMsg(Msg);
 182 }
 183
 184 eNextState FailOneAttempt(AsyncIO *IO)
 185 {
 186         SmtpOutMsg *SendMsg = IO->Data;
 187
 188         if (SendMsg->MyQEntry->Status == 2)
 189                 return eAbort;
 190
 191         /*
 192          * possible ways here:
 193          * - connection timeout
 194          * - dns lookup failed
 195          */
 196         StopClientWatchers(IO);
 197
 198         if (SendMsg->pCurrRelay != NULL)
 199                 SendMsg->pCurrRelay = SendMsg->pCurrRelay->Next;
 200
 201         if (SendMsg->pCurrRelay == NULL) {
 202                 EVS_syslog(LOG_DEBUG, "SMTP: %s Aborting\n", __FUNCTION__);
 203                 return eAbort;
 204         }
 205         if (SendMsg->pCurrRelay->IsIP) {
 206                 EVS_syslog(LOG_DEBUG, "SMTP: %s connecting IP\n", __FUNCTION__);
 207                 return mx_connect_ip(IO);
 208         }
 209         else {
 210                 EVS_syslog(LOG_DEBUG,
 211                            "SMTP: %s resolving next MX Record\n",
 212                            __FUNCTION__);
 213                 return get_one_mx_host_ip(IO);
 214         }
 215 }
 216
 217
 218 void SetConnectStatus(AsyncIO *IO)
 219 {
 220         SmtpOutMsg *SendMsg = IO->Data;
 221         char buf[256];
 222         void *src;
 223
 224         buf[0] = '\0';
 225
 226         if (IO->ConnectMe->IPv6) {
 227                 src = &IO->ConnectMe->Addr.sin6_addr;
 228         }
 229         else {
 230                 struct sockaddr_in *addr;
 231
 232                 addr = (struct sockaddr_in *)&IO->ConnectMe->Addr;
 233                 src = &addr->sin_addr.s_addr;
 234         }
 235
 236         inet_ntop((IO->ConnectMe->IPv6)?AF_INET6:AF_INET,
 237                   src,
 238                   buf,
 239                   sizeof(buf));
 240
 241         if (SendMsg->mx_host == NULL)
 242                 SendMsg->mx_host = "<no MX-Record>";
 243
 244         EVS_syslog(LOG_DEBUG,
 245                   "SMTP client[%ld]: connecting to %s [%s]:%d ...\n",
 246                   SendMsg->n,
 247                   SendMsg->mx_host,
 248                   buf,
 249                   SendMsg->IO.ConnectMe->Port);
 250
 251         SendMsg->MyQEntry->Status = 5;
 252         StrBufPrintf(SendMsg->MyQEntry->StatusMessage,
 253                      "Timeout while connecting %s [%s]:%d ",
 254                      SendMsg->mx_host,
 255                      buf,
 256                      SendMsg->IO.ConnectMe->Port);
 257         SendMsg->IO.NextState = eConnect;
 258 }
 259
 260 /*****************************************************************************
 261  * So we connect our Relay IP here.                                          *
 262  *****************************************************************************/
 263 eNextState mx_connect_ip(AsyncIO *IO)
 264 {
 265         SmtpOutMsg *SendMsg = IO->Data;
 266
 267         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 268
 269         IO->ConnectMe = SendMsg->pCurrRelay;
 270
 271         SetConnectStatus(IO);
 272
 273         return EvConnectSock(IO,
 274                              SMTP_C_ConnTimeout,
 275                              SMTP_C_ReadTimeouts[0],
 276                              1);
 277 }
 278
 279 eNextState get_one_mx_host_ip_done(AsyncIO *IO)
 280 {
 281         SmtpOutMsg *SendMsg = IO->Data;
 282         struct hostent *hostent;
 283
 284         QueryCbDone(IO);
 285
 286         hostent = SendMsg->HostLookup.VParsedDNSReply;
 287         if ((SendMsg->HostLookup.DNSStatus == ARES_SUCCESS) &&
 288             (hostent != NULL) ) {
 289                 memset(&SendMsg->pCurrRelay->Addr, 0, sizeof(struct in6_addr));
 290                 if (SendMsg->pCurrRelay->IPv6) {
 291                         memcpy(&SendMsg->pCurrRelay->Addr.sin6_addr.s6_addr,
 292                                &hostent->h_addr_list[0],
 293                                sizeof(struct in6_addr));
 294
 295                         SendMsg->pCurrRelay->Addr.sin6_family =
 296                                 hostent->h_addrtype;
 297                         SendMsg->pCurrRelay->Addr.sin6_port =
 298                                 htons(DefaultMXPort);
 299                 }
 300                 else {
 301                         struct sockaddr_in *addr;
 302                         /*
 303                          * Bypass the ns lookup result like this:
 304                          * IO->Addr.sin_addr.s_addr = inet_addr("127.0.0.1");
 305                          * addr->sin_addr.s_addr =
 306                          *   htonl((uint32_t)&hostent->h_addr_list[0]);
 307                          */
 308
 309                         addr = (struct sockaddr_in*) &SendMsg->pCurrRelay->Addr;
 310
 311                         memcpy(&addr->sin_addr.s_addr,
 312                                hostent->h_addr_list[0],
 313                                sizeof(uint32_t));
 314
 315                         addr->sin_family = hostent->h_addrtype;
 316                         addr->sin_port   = htons(DefaultMXPort);
 317                 }
 318                 SendMsg->mx_host = SendMsg->pCurrRelay->Host;
 319                 return mx_connect_ip(IO);
 320         }
 321         else
 322                 return FailOneAttempt(IO);
 323 }
 324
 325 eNextState get_one_mx_host_ip(AsyncIO *IO)
 326 {
 327         SmtpOutMsg * SendMsg = IO->Data;
 328         /*
 329          * here we start with the lookup of one host. it might be...
 330          * - the relay host *sigh*
 331          * - the direct hostname if there was no mx record
 332          * - one of the mx'es
 333          */
 334
 335         InitC_ares_dns(IO);
 336
 337         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 338
 339         EVS_syslog(LOG_DEBUG,
 340                   "SMTP client[%ld]: looking up %s-Record %s : %d ...\n",
 341                   SendMsg->n,
 342                   (SendMsg->pCurrRelay->IPv6)? "aaaa": "a",
 343                   SendMsg->pCurrRelay->Host,
 344                   SendMsg->pCurrRelay->Port);
 345
 346         if (!QueueQuery((SendMsg->pCurrRelay->IPv6)? ns_t_aaaa : ns_t_a,
 347                         SendMsg->pCurrRelay->Host,
 348                         &SendMsg->IO,
 349                         &SendMsg->HostLookup,
 350                         get_one_mx_host_ip_done))
 351         {
 352                 SendMsg->MyQEntry->Status = 5;
 353                 StrBufPrintf(SendMsg->MyQEntry->StatusMessage,
 354                              "No MX hosts found for <%s>", SendMsg->node);
 355                 SendMsg->IO.NextState = eTerminateConnection;
 356                 return IO->NextState;
 357         }
 358         IO->NextState = eReadDNSReply;
 359         return IO->NextState;
 360 }
 361
 362
 363 /*****************************************************************************
 364  * here we try to find out about the MX records for our recipients.          *
 365  *****************************************************************************/
 366 eNextState smtp_resolve_mx_record_done(AsyncIO *IO)
 367 {
 368         SmtpOutMsg * SendMsg = IO->Data;
 369         ParsedURL **pp;
 370
 371         QueryCbDone(IO);
 372
 373         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 374         pp = &SendMsg->Relay;
 375         while ((pp != NULL) && (*pp != NULL) && ((*pp)->Next != NULL))
 376                 pp = &(*pp)->Next;
 377
 378         if ((IO->DNS.Query->DNSStatus == ARES_SUCCESS) &&
 379             (IO->DNS.Query->VParsedDNSReply != NULL))
 380         { /* ok, we found mx records. */
 381                 SendMsg->IO.ErrMsg = SendMsg->MyQEntry->StatusMessage;
 382
 383                 SendMsg->CurrMX
 384                         = SendMsg->AllMX
 385                         = IO->DNS.Query->VParsedDNSReply;
 386                 while (SendMsg->CurrMX) {
 387                         int i;
 388                         for (i = 0; i < 2; i++) {
 389                                 ParsedURL *p;
 390
 391                                 p = (ParsedURL*) malloc(sizeof(ParsedURL));
 392                                 memset(p, 0, sizeof(ParsedURL));
 393                                 p->IsIP = 0;
 394                                 p->Port = DefaultMXPort;
 395                                 p->IPv6 = i == 1;
 396                                 p->Host = SendMsg->CurrMX->host;
 397
 398                                 *pp = p;
 399                                 pp = &p->Next;
 400                         }
 401                         SendMsg->CurrMX    = SendMsg->CurrMX->next;
 402                 }
 403                 SendMsg->CXFlags   = SendMsg->CXFlags & F_HAVE_MX;
 404         }
 405         else { /* else fall back to the plain hostname */
 406                 int i;
 407                 for (i = 0; i < 2; i++) {
 408                         ParsedURL *p;
 409
 410                         p = (ParsedURL*) malloc(sizeof(ParsedURL));
 411                         memset(p, 0, sizeof(ParsedURL));
 412                         p->IsIP = 0;
 413                         p->Port = DefaultMXPort;
 414                         p->IPv6 = i == 1;
 415                         p->Host = SendMsg->node;
 416
 417                         *pp = p;
 418                         pp = &p->Next;
 419                 }
 420                 SendMsg->CXFlags   = SendMsg->CXFlags & F_DIRECT;
 421         }
 422         *pp = SendMsg->MyQItem->FallBackHost;
 423         SendMsg->pCurrRelay = SendMsg->Relay;
 424         return get_one_mx_host_ip(IO);
 425 }
 426
 427 eNextState resolve_mx_records(AsyncIO *IO)
 428 {
 429         SmtpOutMsg * SendMsg = IO->Data;
 430
 431         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 432         /* start resolving MX records here. */
 433         if (!QueueQuery(ns_t_mx,
 434                         SendMsg->node,
 435                         &SendMsg->IO,
 436                         &SendMsg->MxLookup,
 437                         smtp_resolve_mx_record_done))
 438         {
 439                 SendMsg->MyQEntry->Status = 5;
 440                 StrBufPrintf(SendMsg->MyQEntry->StatusMessage,
 441                              "No MX hosts found for <%s>", SendMsg->node);
 442                 return IO->NextState;
 443         }
 444         SendMsg->IO.NextState = eReadDNSReply;
 445         return IO->NextState;
 446 }
 447
 448
 449
 450 /******************************************************************************
 451  *  so, we're going to start a SMTP delivery.  lets get it on.                *
 452  ******************************************************************************/
 453
 454 SmtpOutMsg *new_smtp_outmsg(OneQueItem *MyQItem,
 455                             MailQEntry *MyQEntry,
 456                             int MsgCount)
 457 {
 458         SmtpOutMsg * SendMsg;
 459
 460         SendMsg = (SmtpOutMsg *) malloc(sizeof(SmtpOutMsg));
 461         memset(SendMsg, 0, sizeof(SmtpOutMsg));
 462
 463         SendMsg->n                = MsgCount;
 464         SendMsg->MyQEntry         = MyQEntry;
 465         SendMsg->MyQItem          = MyQItem;
 466         SendMsg->pCurrRelay       = MyQItem->URL;
 467
 468         InitIOStruct(&SendMsg->IO,
 469                      SendMsg,
 470                      eReadMessage,
 471                      SMTP_C_ReadServerStatus,
 472                      SMTP_C_DNSFail,
 473                      SMTP_C_DispatchWriteDone,
 474                      SMTP_C_DispatchReadDone,
 475                      SMTP_C_Terminate,
 476                      SMTP_C_ConnFail,
 477                      SMTP_C_Timeout,
 478                      SMTP_C_Shutdown);
 479
 480         return SendMsg;
 481 }
 482
 483 void smtp_try_one_queue_entry(OneQueItem *MyQItem,
 484                               MailQEntry *MyQEntry,
 485                               StrBuf *MsgText,
 486                         /*KeepMsgText allows us to use MsgText as ours.*/
 487                               int KeepMsgText,
 488                               int MsgCount)
 489 {
 490         SmtpOutMsg *SendMsg;
 491
 492         syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 493
 494         SendMsg = new_smtp_outmsg(MyQItem, MyQEntry, MsgCount);
 495         if (KeepMsgText) SendMsg->msgtext = MsgText;
 496         else             SendMsg->msgtext = NewStrBufDup(MsgText);
 497
 498         if (smtp_resolve_recipients(SendMsg)) {
 499
 500                 safestrncpy(
 501                         ((CitContext *)SendMsg->IO.CitContext)->cs_host,
 502                         SendMsg->node,
 503                         sizeof(((CitContext *)
 504                                 SendMsg->IO.CitContext)->cs_host));
 505
 506                 syslog(LOG_DEBUG, "SMTP Starting: [%ld] <%s> CC <%d> \n",
 507                        SendMsg->MyQItem->MessageID,
 508                        ChrPtr(SendMsg->MyQEntry->Recipient),
 509                        ((CitContext*)SendMsg->IO.CitContext)->cs_pid);
 510                 if (SendMsg->pCurrRelay == NULL)
 511                         QueueEventContext(&SendMsg->IO,
 512                                           resolve_mx_records);
 513                 else { /* oh... via relay host */
 514                         if (SendMsg->pCurrRelay->IsIP) {
 515                                 QueueEventContext(&SendMsg->IO,
 516                                                   mx_connect_ip);
 517                         }
 518                         else {
 519                                 /* uneducated admin has chosen to
 520                                    add DNS to the equation... */
 521                                 QueueEventContext(&SendMsg->IO,
 522                                                   get_one_mx_host_ip);
 523                         }
 524                 }
 525         }
 526         else {
 527                 /* No recipients? well fail then. */
 528                 if ((SendMsg==NULL) ||
 529                     (SendMsg->MyQEntry == NULL)) {
 530                         SendMsg->MyQEntry->Status = 5;
 531                         StrBufPlain(SendMsg->MyQEntry->StatusMessage,
 532                                     HKEY("Invalid Recipient!"));
 533                 }
 534                 FinalizeMessageSend(SendMsg);
 535         }
 536 }
 537
 538
 539
 540
 541
 542
 543 /*****************************************************************************/
 544 /*                     SMTP CLIENT DISPATCHER                                */
 545 /*****************************************************************************/
 546
 547 void SMTPSetTimeout(eNextState NextTCPState, SmtpOutMsg *pMsg)
 548 {
 549         double Timeout = 0.0;
 550         AsyncIO *IO = &pMsg->IO;
 551
 552         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 553
 554         switch (NextTCPState) {
 555         case eSendFile:
 556         case eSendReply:
 557         case eSendMore:
 558                 Timeout = SMTP_C_SendTimeouts[pMsg->State];
 559                 if (pMsg->State == eDATABody) {
 560                         /* if we're sending a huge message,
 561                          * we need more time.
 562                          */
 563                         Timeout += StrLength(pMsg->msgtext) / 1024;
 564                 }
 565                 break;
 566         case eReadMessage:
 567                 Timeout = SMTP_C_ReadTimeouts[pMsg->State];
 568                 if (pMsg->State == eDATATerminateBody) {
 569                         /*
 570                          * some mailservers take a nap before accepting
 571                          * the message content inspection and such.
 572                          */
 573                         Timeout += StrLength(pMsg->msgtext) / 1024;
 574                 }
 575                 break;
 576         case eSendDNSQuery:
 577         case eReadDNSReply:
 578         case eDBQuery:
 579         case eReadFile:
 580         case eReadMore:
 581         case eReadPayload:
 582         case eConnect:
 583         case eTerminateConnection:
 584         case eAbort:
 585                 return;
 586         }
 587         SetNextTimeout(&pMsg->IO, Timeout);
 588 }
 589 eNextState SMTP_C_DispatchReadDone(AsyncIO *IO)
 590 {
 591         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 592         SmtpOutMsg *pMsg = IO->Data;
 593         eNextState rc;
 594
 595         rc = ReadHandlers[pMsg->State](pMsg);
 596         if (rc != eAbort)
 597         {
 598                 pMsg->State++;
 599                 SMTPSetTimeout(rc, pMsg);
 600         }
 601         return rc;
 602 }
 603 eNextState SMTP_C_DispatchWriteDone(AsyncIO *IO)
 604 {
 605         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 606         SmtpOutMsg *pMsg = IO->Data;
 607         eNextState rc;
 608
 609         rc = SendHandlers[pMsg->State](pMsg);
 610         SMTPSetTimeout(rc, pMsg);
 611         return rc;
 612 }
 613
 614
 615 /*****************************************************************************/
 616 /*                     SMTP CLIENT ERROR CATCHERS                            */
 617 /*****************************************************************************/
 618 eNextState SMTP_C_Terminate(AsyncIO *IO)
 619 {
 620         SmtpOutMsg *pMsg = IO->Data;
 621
 622         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 623         FinalizeMessageSend(pMsg);
 624         return eAbort;
 625 }
 626 eNextState SMTP_C_Timeout(AsyncIO *IO)
 627 {
 628         SmtpOutMsg *pMsg = IO->Data;
 629
 630         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 631         StrBufPlain(IO->ErrMsg, CKEY(ReadErrors[pMsg->State]));
 632         return FailOneAttempt(IO);
 633 }
 634 eNextState SMTP_C_ConnFail(AsyncIO *IO)
 635 {
 636         SmtpOutMsg *pMsg = IO->Data;
 637
 638         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 639         StrBufPlain(IO->ErrMsg, CKEY(ReadErrors[pMsg->State]));
 640         return FailOneAttempt(IO);
 641 }
 642 eNextState SMTP_C_DNSFail(AsyncIO *IO)
 643 {
 644         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 645         return FailOneAttempt(IO);
 646 }
 647 eNextState SMTP_C_Shutdown(AsyncIO *IO)
 648 {
 649         EVS_syslog(LOG_DEBUG, "SMTP: %s\n", __FUNCTION__);
 650         SmtpOutMsg *pMsg = IO->Data;
 651
 652         pMsg->MyQEntry->Status = 3;
 653         StrBufPlain(pMsg->MyQEntry->StatusMessage,
 654                     HKEY("server shutdown during message submit."));
 655         FinalizeMessageSend(pMsg);
 656         return eAbort;
 657 }
 658
 659
 660 /**
 661  * @brief lineread Handler;
 662  * understands when to read more SMTP lines, and when this is a one-lined reply.
 663  */
 664 eReadState SMTP_C_ReadServerStatus(AsyncIO *IO)
 665 {
 666         eReadState Finished = eBufferNotEmpty;
 667
 668         while (Finished == eBufferNotEmpty) {
 669                 Finished = StrBufChunkSipLine(IO->IOBuf, &IO->RecvBuf);
 670
 671                 switch (Finished) {
 672                 case eMustReadMore: /// read new from socket...
 673                         return Finished;
 674                         break;
 675                 case eBufferNotEmpty: /* shouldn't happen... */
 676                 case eReadSuccess: /// done for now...
 677                         if (StrLength(IO->IOBuf) < 4)
 678                                 continue;
 679                         if (ChrPtr(IO->IOBuf)[3] == '-')
 680                                 Finished = eBufferNotEmpty;
 681                         else
 682                                 return Finished;
 683                         break;
 684                 case eReadFail: /// WHUT?
 685                         ///todo: shut down!
 686                         break;
 687                 }
 688         }
 689         return Finished;
 690 }
 691
 692 CTDL_MODULE_INIT(smtp_eventclient)
 693 {
 694         return "smtpeventclient";
 695 }