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