src/src/transports/lmtp.c

   1 /*************************************************
   2 *     Exim - an Internet mail transport agent    *
   3 *************************************************/
   4
   5 /* Copyright (c) University of Cambridge 1995 - 2018 */
   6 /* See the file NOTICE for conditions of use and distribution. */
   7
   8
   9 #include "../exim.h"
  10 #include "lmtp.h"
  11
  12 #define PENDING_OK 256
  13
  14
  15 /* Options specific to the lmtp transport. They must be in alphabetic
  16 order (note that "_" comes before the lower case letters). Those starting
  17 with "*" are not settable by the user but are used by the option-reading
  18 software for alternative value types. Some options are stored in the transport
  19 instance block so as to be publicly visible; these are flagged with opt_public.
  20 */
  21
  22 optionlist lmtp_transport_options[] = {
  23   { "batch_id",          opt_stringptr | opt_public,
  24       (void *)offsetof(transport_instance, batch_id) },
  25   { "batch_max",         opt_int | opt_public,
  26       (void *)offsetof(transport_instance, batch_max) },
  27   { "command",           opt_stringptr,
  28       (void *)offsetof(lmtp_transport_options_block, cmd) },
  29   { "ignore_quota",      opt_bool,
  30       (void *)offsetof(lmtp_transport_options_block, ignore_quota) },
  31   { "socket",            opt_stringptr,
  32       (void *)offsetof(lmtp_transport_options_block, skt) },
  33   { "timeout",           opt_time,
  34       (void *)offsetof(lmtp_transport_options_block, timeout) }
  35 };
  36
  37 /* Size of the options list. An extern variable has to be used so that its
  38 address can appear in the tables drtables.c. */
  39
  40 int lmtp_transport_options_count =
  41   sizeof(lmtp_transport_options)/sizeof(optionlist);
  42
  43
  44 #ifdef MACRO_PREDEF
  45
  46 /* Dummy values */
  47 lmtp_transport_options_block lmtp_transport_option_defaults = {0};
  48 void lmtp_transport_init(transport_instance *tblock) {}
  49 BOOL lmtp_transport_entry(transport_instance *tblock, address_item *addr) {return FALSE;}
  50
  51 #else   /*!MACRO_PREDEF*/
  52
  53
  54 /* Default private options block for the lmtp transport. */
  55
  56 lmtp_transport_options_block lmtp_transport_option_defaults = {
  57   NULL,           /* cmd */
  58   NULL,           /* skt */
  59   5*60,           /* timeout */
  60   0,              /* options */
  61   FALSE           /* ignore_quota */
  62 };
  63
  64
  65
  66 /*************************************************
  67 *          Initialization entry point            *
  68 *************************************************/
  69
  70 /* Called for each instance, after its options have been read, to
  71 enable consistency checks to be done, or anything else that needs
  72 to be set up. */
  73
  74 void
  75 lmtp_transport_init(transport_instance *tblock)
  76 {
  77 lmtp_transport_options_block *ob =
  78   (lmtp_transport_options_block *)(tblock->options_block);
  79
  80 /* Either the command field or the socket field must be set */
  81
  82 if ((ob->cmd == NULL) == (ob->skt == NULL))
  83   log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
  84     "one (and only one) of command or socket must be set for the %s transport",
  85     tblock->name);
  86
  87 /* If a fixed uid field is set, then a gid field must also be set. */
  88
  89 if (tblock->uid_set && !tblock->gid_set && tblock->expand_gid == NULL)
  90   log_write(0, LOG_PANIC_DIE|LOG_CONFIG,
  91     "user set without group for the %s transport", tblock->name);
  92
  93 /* Set up the bitwise options for transport_write_message from the various
  94 driver options. Only one of body_only and headers_only can be set. */
  95
  96 ob->options |=
  97   (tblock->body_only? topt_no_headers : 0) |
  98   (tblock->headers_only? topt_no_body : 0) |
  99   (tblock->return_path_add? topt_add_return_path : 0) |
 100   (tblock->delivery_date_add? topt_add_delivery_date : 0) |
 101   (tblock->envelope_to_add? topt_add_envelope_to : 0) |
 102   topt_use_crlf | topt_end_dot;
 103 }
 104
 105
 106 /*************************************************
 107 *          Check an LMTP response                *
 108 *************************************************/
 109
 110 /* This function is given an errno code and the LMTP response buffer to
 111 analyse. It sets an appropriate message and puts the first digit of the
 112 response code into the yield variable. If no response was actually read, a
 113 suitable digit is chosen.
 114
 115 Arguments:
 116   errno_value  pointer to the errno value
 117   more_errno   from the top address for use with ERRNO_FILTER_FAIL
 118   buffer       the LMTP response buffer
 119   yield        where to put a one-digit LMTP response code
 120   message      where to put an error message
 121
 122 Returns:       TRUE if a "QUIT" command should be sent, else FALSE
 123 */
 124
 125 static BOOL check_response(int *errno_value, int more_errno, uschar *buffer,
 126   int *yield, uschar **message)
 127 {
 128 *yield = '4';    /* Default setting is to give a temporary error */
 129
 130 /* Handle response timeout */
 131
 132 if (*errno_value == ETIMEDOUT)
 133   {
 134   *message = string_sprintf("LMTP timeout after %s", big_buffer);
 135   if (transport_count > 0)
 136     *message = string_sprintf("%s (%d bytes written)", *message,
 137       transport_count);
 138   *errno_value = 0;
 139   return FALSE;
 140   }
 141
 142 /* Handle malformed LMTP response */
 143
 144 if (*errno_value == ERRNO_SMTPFORMAT)
 145   {
 146   *message = string_sprintf("Malformed LMTP response after %s: %s",
 147     big_buffer, string_printing(buffer));
 148   return FALSE;
 149   }
 150
 151 /* Handle a failed filter process error; can't send QUIT as we mustn't
 152 end the DATA. */
 153
 154 if (*errno_value == ERRNO_FILTER_FAIL)
 155   {
 156   *message = string_sprintf("transport filter process failed (%d)%s",
 157     more_errno,
 158     (more_errno == EX_EXECFAILED)? ": unable to execute command" : "");
 159   return FALSE;
 160   }
 161
 162 /* Handle a failed add_headers expansion; can't send QUIT as we mustn't
 163 end the DATA. */
 164
 165 if (*errno_value == ERRNO_CHHEADER_FAIL)
 166   {
 167   *message =
 168     string_sprintf("failed to expand headers_add or headers_remove: %s",
 169       expand_string_message);
 170   return FALSE;
 171   }
 172
 173 /* Handle failure to write a complete data block */
 174
 175 if (*errno_value == ERRNO_WRITEINCOMPLETE)
 176   {
 177   *message = string_sprintf("failed to write a data block");
 178   return FALSE;
 179   }
 180
 181 /* Handle error responses from the remote process. */
 182
 183 if (buffer[0] != 0)
 184   {
 185   const uschar *s = string_printing(buffer);
 186   *message = string_sprintf("LMTP error after %s: %s", big_buffer, s);
 187   *yield = buffer[0];
 188   return TRUE;
 189   }
 190
 191 /* No data was read. If there is no errno, this must be the EOF (i.e.
 192 connection closed) case, which causes deferral. Otherwise, leave the errno
 193 value to be interpreted. In all cases, we have to assume the connection is now
 194 dead. */
 195
 196 if (*errno_value == 0)
 197   {
 198   *errno_value = ERRNO_SMTPCLOSED;
 199   *message = string_sprintf("LMTP connection closed after %s", big_buffer);
 200   }
 201
 202 return FALSE;
 203 }
 204
 205
 206
 207 /*************************************************
 208 *             Write LMTP command                 *
 209 *************************************************/
 210
 211 /* The formatted command is left in big_buffer so that it can be reflected in
 212 any error message.
 213
 214 Arguments:
 215   fd         the fd to write to
 216   format     a format, starting with one of
 217              of HELO, MAIL FROM, RCPT TO, DATA, ".", or QUIT.
 218   ...        data for the format
 219
 220 Returns:     TRUE if successful, FALSE if not, with errno set
 221 */
 222
 223 static BOOL
 224 lmtp_write_command(int fd, const char *format, ...)
 225 {
 226 gstring gs = { .size = big_buffer_size, .ptr = 0, .s = big_buffer };
 227 int rc;
 228 va_list ap;
 229
 230 va_start(ap, format);
 231 if (!string_vformat(&gs, FALSE, CS format, ap))
 232   {
 233   va_end(ap);
 234   errno = ERRNO_SMTPFORMAT;
 235   return FALSE;
 236   }
 237 va_end(ap);
 238 DEBUG(D_transport|D_v) debug_printf("  LMTP>> %s", string_from_gstring(&gs));
 239 rc = write(fd, gs.s, gs.ptr);
 240 gs.ptr -= 2; string_from_gstring(&gs); /* remove \r\n for debug and error message */
 241 if (rc > 0) return TRUE;
 242 DEBUG(D_transport) debug_printf("write failed: %s\n", strerror(errno));
 243 return FALSE;
 244 }
 245
 246
 247
 248
 249 /*************************************************
 250 *              Read LMTP response                *
 251 *************************************************/
 252
 253 /* This function reads an LMTP response with a timeout, and returns the
 254 response in the given buffer. It also analyzes the first digit of the reply
 255 code and returns FALSE if it is not acceptable.
 256
 257 FALSE is also returned after a reading error. In this case buffer[0] will be
 258 zero, and the error code will be in errno.
 259
 260 Arguments:
 261   f         a file to read from
 262   buffer    where to put the response
 263   size      the size of the buffer
 264   okdigit   the expected first digit of the response
 265   timeout   the timeout to use
 266
 267 Returns:    TRUE if a valid, non-error response was received; else FALSE
 268 */
 269
 270 static BOOL
 271 lmtp_read_response(FILE *f, uschar *buffer, int size, int okdigit, int timeout)
 272 {
 273 int count;
 274 uschar *ptr = buffer;
 275 uschar *readptr = buffer;
 276
 277 /* Ensure errno starts out zero */
 278
 279 errno = 0;
 280
 281 /* Loop for handling LMTP responses that do not all come in one line. */
 282
 283 for (;;)
 284   {
 285   /* If buffer is too full, something has gone wrong. */
 286
 287   if (size < 10)
 288     {
 289     *readptr = 0;
 290     errno = ERRNO_SMTPFORMAT;
 291     return FALSE;
 292     }
 293
 294   /* Loop to cover the read getting interrupted. */
 295
 296   for (;;)
 297     {
 298     char *rc;
 299     int save_errno;
 300
 301     *readptr = 0;           /* In case nothing gets read */
 302     sigalrm_seen = FALSE;
 303     ALARM(timeout);
 304     rc = Ufgets(readptr, size-1, f);
 305     save_errno = errno;
 306     ALARM_CLR(0);
 307     errno = save_errno;
 308
 309     if (rc != NULL) break;  /* A line has been read */
 310
 311     /* Handle timeout; must do this first because it uses EINTR */
 312
 313     if (sigalrm_seen) errno = ETIMEDOUT;
 314
 315     /* If some other interrupt arrived, just retry. We presume this to be rare,
 316     but it can happen (e.g. the SIGUSR1 signal sent by exiwhat causes
 317     read() to exit). */
 318
 319     else if (errno == EINTR)
 320       {
 321       DEBUG(D_transport) debug_printf("EINTR while reading LMTP response\n");
 322       continue;
 323       }
 324
 325     /* Handle other errors, including EOF; ensure buffer is completely empty. */
 326
 327     buffer[0] = 0;
 328     return FALSE;
 329     }
 330
 331   /* Adjust size in case we have to read another line, and adjust the
 332   count to be the length of the line we are about to inspect. */
 333
 334   count = Ustrlen(readptr);
 335   size -= count;
 336   count += readptr - ptr;
 337
 338   /* See if the final two characters in the buffer are \r\n. If not, we
 339   have to read some more. At least, that is what we should do on a strict
 340   interpretation of the RFC. But accept LF as well, as we do for SMTP. */
 341
 342   if (ptr[count-1] != '\n')
 343     {
 344     DEBUG(D_transport)
 345       {
 346       debug_printf("LMTP input line incomplete in one buffer:\n  ");
 347       for (int i = 0; i < count; i++)
 348         {
 349         int c = (ptr[i]);
 350         if (mac_isprint(c)) debug_printf("%c", c); else debug_printf("<%d>", c);
 351         }
 352       debug_printf("\n");
 353       }
 354     readptr = ptr + count;
 355     continue;
 356     }
 357
 358   /* Remove any whitespace at the end of the buffer. This gets rid of CR, LF
 359   etc. at the end. Show it, if debugging, formatting multi-line responses. */
 360
 361   while (count > 0 && isspace(ptr[count-1])) count--;
 362   ptr[count] = 0;
 363
 364   DEBUG(D_transport|D_v)
 365     {
 366     uschar *s = ptr;
 367     uschar *t = ptr;
 368     while (*t != 0)
 369       {
 370       while (*t != 0 && *t != '\n') t++;
 371       debug_printf("  %s %*s\n", (s == ptr)? "LMTP<<" : "      ",
 372         (int)(t-s), s);
 373       if (*t == 0) break;
 374       s = t = t + 1;
 375       }
 376     }
 377
 378   /* Check the format of the response: it must start with three digits; if
 379   these are followed by a space or end of line, the response is complete. If
 380   they are followed by '-' this is a multi-line response and we must look for
 381   another line until the final line is reached. The only use made of multi-line
 382   responses is to pass them back as error messages. We therefore just
 383   concatenate them all within the buffer, which should be large enough to
 384   accept any reasonable number of lines. A multiline response may already
 385   have been read in one go - hence the loop here. */
 386
 387   for(;;)
 388     {
 389     uschar *p;
 390     if (count < 3 ||
 391        !isdigit(ptr[0]) ||
 392        !isdigit(ptr[1]) ||
 393        !isdigit(ptr[2]) ||
 394        (ptr[3] != '-' && ptr[3] != ' ' && ptr[3] != 0))
 395       {
 396       errno = ERRNO_SMTPFORMAT;    /* format error */
 397       return FALSE;
 398       }
 399
 400     /* If a single-line response, exit the loop */
 401
 402     if (ptr[3] != '-') break;
 403
 404     /* For a multi-line response see if the next line is already read, and if
 405     so, stay in this loop to check it. */
 406
 407     p = ptr + 3;
 408     while (*(++p) != 0)
 409       {
 410       if (*p == '\n')
 411         {
 412         ptr = ++p;
 413         break;
 414         }
 415       }
 416     if (*p == 0) break;   /* No more lines to check */
 417     }
 418
 419   /* End of response. If the last of the lines we are looking at is the final
 420   line, we are done. Otherwise more data has to be read. */
 421
 422   if (ptr[3] != '-') break;
 423
 424   /* Move the reading pointer upwards in the buffer and insert \n in case this
 425   is an error message that subsequently gets printed. Set the scanning pointer
 426   to the reading pointer position. */
 427
 428   ptr += count;
 429   *ptr++ = '\n';
 430   size--;
 431   readptr = ptr;
 432   }
 433
 434 /* Return a value that depends on the LMTP return code. Ensure that errno is
 435 zero, because the caller of this function looks at errno when FALSE is
 436 returned, to distinguish between an unexpected return code and other errors
 437 such as timeouts, lost connections, etc. */
 438
 439 errno = 0;
 440 return buffer[0] == okdigit;
 441 }
 442
 443
 444
 445
 446
 447
 448 /*************************************************
 449 *              Main entry point                  *
 450 *************************************************/
 451
 452 /* See local README for interface details. For setup-errors, this transport
 453 returns FALSE, indicating that the first address has the status for all; in
 454 normal cases it returns TRUE, indicating that each address has its own status
 455 set. */
 456
 457 BOOL
 458 lmtp_transport_entry(
 459   transport_instance *tblock,      /* data for this instantiation */
 460   address_item *addrlist)          /* address(es) we are working on */
 461 {
 462 pid_t pid = 0;
 463 FILE *out;
 464 lmtp_transport_options_block *ob =
 465   (lmtp_transport_options_block *)(tblock->options_block);
 466 struct sockaddr_un sockun;         /* don't call this "sun" ! */
 467 int timeout = ob->timeout;
 468 int fd_in = -1, fd_out = -1;
 469 int code, save_errno;
 470 BOOL send_data;
 471 BOOL yield = FALSE;
 472 uschar *igquotstr = US"";
 473 uschar *sockname = NULL;
 474 const uschar **argv;
 475 uschar buffer[256];
 476
 477 DEBUG(D_transport) debug_printf("%s transport entered\n", tblock->name);
 478
 479 /* Initialization ensures that either a command or a socket is specified, but
 480 not both. When a command is specified, call the common function for creating an
 481 argument list and expanding the items. */
 482
 483 if (ob->cmd)
 484   {
 485   DEBUG(D_transport) debug_printf("using command %s\n", ob->cmd);
 486   sprintf(CS buffer, "%.50s transport", tblock->name);
 487   if (!transport_set_up_command(&argv, ob->cmd, TRUE, PANIC, addrlist, buffer,
 488        NULL))
 489     return FALSE;
 490
 491   /* If the -N option is set, can't do any more. Presume all has gone well. */
 492   if (f.dont_deliver)
 493     goto MINUS_N;
 494
 495 /* As this is a local transport, we are already running with the required
 496 uid/gid and current directory. Request that the new process be a process group
 497 leader, so we can kill it and all its children on an error. */
 498
 499   if ((pid = child_open(USS argv, NULL, 0, &fd_in, &fd_out, TRUE)) < 0)
 500     {
 501     addrlist->message = string_sprintf(
 502       "Failed to create child process for %s transport: %s", tblock->name,
 503         strerror(errno));
 504     return FALSE;
 505     }
 506   }
 507
 508 /* When a socket is specified, expand the string and create a socket. */
 509
 510 else
 511   {
 512   DEBUG(D_transport) debug_printf("using socket %s\n", ob->skt);
 513   sockname = expand_string(ob->skt);
 514   if (sockname == NULL)
 515     {
 516     addrlist->message = string_sprintf("Expansion of \"%s\" (socket setting "
 517       "for %s transport) failed: %s", ob->skt, tblock->name,
 518       expand_string_message);
 519     return FALSE;
 520     }
 521   if ((fd_in = fd_out = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
 522     {
 523     addrlist->message = string_sprintf(
 524       "Failed to create socket %s for %s transport: %s",
 525         ob->skt, tblock->name, strerror(errno));
 526     return FALSE;
 527     }
 528
 529   /* If the -N option is set, can't do any more. Presume all has gone well. */
 530   if (f.dont_deliver)
 531     goto MINUS_N;
 532
 533   sockun.sun_family = AF_UNIX;
 534   sprintf(sockun.sun_path, "%.*s", (int)(sizeof(sockun.sun_path)-1), sockname);
 535   if(connect(fd_out, (struct sockaddr *)(&sockun), sizeof(sockun)) == -1)
 536     {
 537     addrlist->message = string_sprintf(
 538       "Failed to connect to socket %s for %s transport: %s",
 539         sockun.sun_path, tblock->name, strerror(errno));
 540     return FALSE;
 541     }
 542   }
 543
 544
 545 /* Make the output we are going to read into a file. */
 546
 547 out = fdopen(fd_out, "rb");
 548
 549 /* Now we must implement the LMTP protocol. It is like SMTP, except that after
 550 the end of the message, a return code for every accepted RCPT TO is sent. This
 551 allows for message+recipient checks after the message has been received. */
 552
 553 /* First thing is to wait for an initial greeting. */
 554
 555 Ustrcpy(big_buffer, "initial connection");
 556 if (!lmtp_read_response(out, buffer, sizeof(buffer), '2',
 557   timeout)) goto RESPONSE_FAILED;
 558
 559 /* Next, we send a LHLO command, and expect a positive response */
 560
 561 if (!lmtp_write_command(fd_in, "%s %s\r\n", "LHLO",
 562   primary_hostname)) goto WRITE_FAILED;
 563
 564 if (!lmtp_read_response(out, buffer, sizeof(buffer), '2',
 565      timeout)) goto RESPONSE_FAILED;
 566
 567 /* If the ignore_quota option is set, note whether the server supports the
 568 IGNOREQUOTA option, and if so, set an appropriate addition for RCPT. */
 569
 570 if (ob->ignore_quota)
 571   igquotstr = (pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer,
 572     Ustrlen(CS buffer), 0, PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
 573
 574 /* Now the envelope sender */
 575
 576 if (!lmtp_write_command(fd_in, "MAIL FROM:<%s>\r\n", return_path))
 577   goto WRITE_FAILED;
 578
 579 if (!lmtp_read_response(out, buffer, sizeof(buffer), '2', timeout))
 580   {
 581   if (errno == 0 && buffer[0] == '4')
 582     {
 583     errno = ERRNO_MAIL4XX;
 584     addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
 585     }
 586   goto RESPONSE_FAILED;
 587   }
 588
 589 /* Next, we hand over all the recipients. Some may be permanently or
 590 temporarily rejected; others may be accepted, for now. */
 591
 592 send_data = FALSE;
 593 for (address_item * addr = addrlist; addr; addr = addr->next)
 594   {
 595   if (!lmtp_write_command(fd_in, "RCPT TO:<%s>%s\r\n",
 596        transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr))
 597     goto WRITE_FAILED;
 598   if (lmtp_read_response(out, buffer, sizeof(buffer), '2', timeout))
 599     {
 600     send_data = TRUE;
 601     addr->transport_return = PENDING_OK;
 602     }
 603   else
 604     {
 605     if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
 606     addr->message = string_sprintf("LMTP error after %s: %s", big_buffer,
 607       string_printing(buffer));
 608     setflag(addr, af_pass_message);   /* Allow message to go to user */
 609     if (buffer[0] == '5') addr->transport_return = FAIL; else
 610       {
 611       addr->basic_errno = ERRNO_RCPT4XX;
 612       addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
 613       }
 614     }
 615   }
 616
 617 /* Now send the text of the message if there were any good recipients. */
 618
 619 if (send_data)
 620   {
 621   BOOL ok;
 622   transport_ctx tctx = {
 623     {fd_in},
 624     tblock,
 625     addrlist,
 626     US".", US"..",
 627     ob->options
 628   };
 629
 630   if (!lmtp_write_command(fd_in, "DATA\r\n")) goto WRITE_FAILED;
 631   if (!lmtp_read_response(out, buffer, sizeof(buffer), '3', timeout))
 632     {
 633     if (errno == 0 && buffer[0] == '4')
 634       {
 635       errno = ERRNO_DATA4XX;
 636       addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
 637       }
 638     goto RESPONSE_FAILED;
 639     }
 640
 641   sigalrm_seen = FALSE;
 642   transport_write_timeout = timeout;
 643   Ustrcpy(big_buffer, "sending data block");   /* For error messages */
 644   DEBUG(D_transport|D_v)
 645     debug_printf("  LMTP>> writing message and terminating \".\"\n");
 646
 647   transport_count = 0;
 648   ok = transport_write_message(&tctx, 0);
 649
 650   /* Failure can either be some kind of I/O disaster (including timeout),
 651   or the failure of a transport filter or the expansion of added headers. */
 652
 653   if (!ok)
 654     {
 655     buffer[0] = 0;              /* There hasn't been a response */
 656     goto RESPONSE_FAILED;
 657     }
 658
 659   Ustrcpy(big_buffer, "end of data");   /* For error messages */
 660
 661   /* We now expect a response for every address that was accepted above,
 662   in the same order. For those that get a response, their status is fixed;
 663   any that are accepted have been handed over, even if later responses crash -
 664   at least, that's how I read RFC 2033. */
 665
 666   for (address_item * addr = addrlist; addr; addr = addr->next)
 667     {
 668     if (addr->transport_return != PENDING_OK) continue;
 669
 670     if (lmtp_read_response(out, buffer, sizeof(buffer), '2', timeout))
 671       {
 672       addr->transport_return = OK;
 673       if (LOGGING(smtp_confirmation))
 674         {
 675         const uschar *s = string_printing(buffer);
 676         /* de-const safe here as string_printing known to have alloc'n'copied */
 677         addr->message = (s == buffer)? US string_copy(s) : US s;
 678         }
 679       }
 680     /* If the response has failed badly, use it for all the remaining pending
 681     addresses and give up. */
 682
 683     else if (errno != 0 || buffer[0] == 0)
 684       {
 685       save_errno = errno;
 686       check_response(&save_errno, addr->more_errno, buffer, &code,
 687         &(addr->message));
 688       addr->transport_return = (code == '5')? FAIL : DEFER;
 689       for (address_item * a = addr->next; a; a = a->next)
 690         {
 691         if (a->transport_return != PENDING_OK) continue;
 692         a->basic_errno = addr->basic_errno;
 693         a->message = addr->message;
 694         a->transport_return = addr->transport_return;
 695         }
 696       break;
 697       }
 698
 699     /* Otherwise, it's an LMTP error code return for one address */
 700
 701     else
 702       {
 703       if (buffer[0] == '4')
 704         {
 705         addr->basic_errno = ERRNO_DATA4XX;
 706         addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
 707         }
 708       addr->message = string_sprintf("LMTP error after %s: %s", big_buffer,
 709         string_printing(buffer));
 710       addr->transport_return = (buffer[0] == '5')? FAIL : DEFER;
 711       setflag(addr, af_pass_message);   /* Allow message to go to user */
 712       }
 713     }
 714   }
 715
 716 /* The message transaction has completed successfully - this doesn't mean that
 717 all the addresses have necessarily been transferred, but each has its status
 718 set, so we change the yield to TRUE. */
 719
 720 yield = TRUE;
 721 (void) lmtp_write_command(fd_in, "QUIT\r\n");
 722 (void) lmtp_read_response(out, buffer, sizeof(buffer), '2', 1);
 723
 724 goto RETURN;
 725
 726
 727 /* Come here if any call to read_response, other than a response after the data
 728 phase, failed. Put the error in the top address - this will be replicated
 729 because the yield is still FALSE. (But omit ETIMEDOUT, as there will already be
 730 a suitable message.) Analyse the error, and if if isn't too bad, send a QUIT
 731 command. Wait for the response with a short timeout, so we don't wind up this
 732 process before the far end has had time to read the QUIT. */
 733
 734 RESPONSE_FAILED:
 735
 736 save_errno = errno;
 737 if (errno != ETIMEDOUT && errno != 0) addrlist->basic_errno = errno;
 738 addrlist->message = NULL;
 739
 740 if (check_response(&save_errno, addrlist->more_errno,
 741     buffer, &code, &(addrlist->message)))
 742   {
 743   (void) lmtp_write_command(fd_in, "QUIT\r\n");
 744   (void) lmtp_read_response(out, buffer, sizeof(buffer), '2', 1);
 745   }
 746
 747 addrlist->transport_return = (code == '5')? FAIL : DEFER;
 748 if (code == '4' && save_errno > 0)
 749   addrlist->message = string_sprintf("%s: %s", addrlist->message,
 750     strerror(save_errno));
 751 goto KILL_AND_RETURN;
 752
 753 /* Come here if there are errors during writing of a command or the message
 754 itself. This error will be applied to all the addresses. */
 755
 756 WRITE_FAILED:
 757
 758 addrlist->transport_return = PANIC;
 759 addrlist->basic_errno = errno;
 760 if (errno == ERRNO_CHHEADER_FAIL)
 761   addrlist->message =
 762     string_sprintf("Failed to expand headers_add or headers_remove: %s",
 763       expand_string_message);
 764 else if (errno == ERRNO_FILTER_FAIL)
 765   addrlist->message = string_sprintf("Filter process failure");
 766 else if (errno == ERRNO_WRITEINCOMPLETE)
 767   addrlist->message = string_sprintf("Failed repeatedly to write data");
 768 else if (errno == ERRNO_SMTPFORMAT)
 769   addrlist->message = US"overlong LMTP command generated";
 770 else
 771   addrlist->message = string_sprintf("Error %d", errno);
 772
 773 /* Come here after errors. Kill off the process. */
 774
 775 KILL_AND_RETURN:
 776
 777 if (pid > 0) killpg(pid, SIGKILL);
 778
 779 /* Come here from all paths after the subprocess is created. Wait for the
 780 process, but with a timeout. */
 781
 782 RETURN:
 783
 784 (void)child_close(pid, timeout);
 785
 786 if (fd_in >= 0) (void)close(fd_in);
 787 if (fd_out >= 0) (void)fclose(out);
 788
 789 DEBUG(D_transport)
 790   debug_printf("%s transport yields %d\n", tblock->name, yield);
 791
 792 return yield;
 793
 794
 795 MINUS_N:
 796   DEBUG(D_transport)
 797     debug_printf("*** delivery by %s transport bypassed by -N option",
 798       tblock->name);
 799   addrlist->transport_return = OK;
 800   return FALSE;
 801 }
 802
 803 #endif  /*!MACRO_PREDEF*/
 804 /* End of transport/lmtp.c */