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       OPT_OFF(transport_instance, batch_id) },
  25   { "batch_max",         opt_int | opt_public,
  26       OPT_OFF(transport_instance, batch_max) },
  27   { "command",           opt_stringptr,
  28       OPT_OFF(lmtp_transport_options_block, cmd) },
  29   { "ignore_quota",      opt_bool,
  30       OPT_OFF(lmtp_transport_options_block, ignore_quota) },
  31   { "socket",            opt_stringptr,
  32       OPT_OFF(lmtp_transport_options_block, skt) },
  33   { "timeout",           opt_time,
  34       OPT_OFF(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 = US"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 /*XXX see comment in smtp_write_command() regarding leaving stuff in
 232 big_buffer */
 233
 234 va_start(ap, format);
 235 if (!string_vformat(&gs, SVFMT_TAINT_NOCHK, CS format, ap))
 236   {
 237   va_end(ap);
 238   errno = ERRNO_SMTPFORMAT;
 239   return FALSE;
 240   }
 241 va_end(ap);
 242 DEBUG(D_transport|D_v) debug_printf("  LMTP>> %s", string_from_gstring(&gs));
 243 rc = write(fd, gs.s, gs.ptr);
 244 gs.ptr -= 2; string_from_gstring(&gs); /* remove \r\n for debug and error message */
 245 if (rc > 0) return TRUE;
 246 DEBUG(D_transport) debug_printf("write failed: %s\n", strerror(errno));
 247 return FALSE;
 248 }
 249
 250
 251
 252
 253 /*************************************************
 254 *              Read LMTP response                *
 255 *************************************************/
 256
 257 /* This function reads an LMTP response with a timeout, and returns the
 258 response in the given buffer. It also analyzes the first digit of the reply
 259 code and returns FALSE if it is not acceptable.
 260
 261 FALSE is also returned after a reading error. In this case buffer[0] will be
 262 zero, and the error code will be in errno.
 263
 264 Arguments:
 265   f         a file to read from
 266   buffer    where to put the response
 267   size      the size of the buffer
 268   okdigit   the expected first digit of the response
 269   timeout   the timeout to use
 270
 271 Returns:    TRUE if a valid, non-error response was received; else FALSE
 272 */
 273
 274 static BOOL
 275 lmtp_read_response(FILE *f, uschar *buffer, int size, int okdigit, int timeout)
 276 {
 277 int count;
 278 uschar *ptr = buffer;
 279 uschar *readptr = buffer;
 280
 281 /* Ensure errno starts out zero */
 282
 283 errno = 0;
 284
 285 /* Loop for handling LMTP responses that do not all come in one line. */
 286
 287 for (;;)
 288   {
 289   /* If buffer is too full, something has gone wrong. */
 290
 291   if (size < 10)
 292     {
 293     *readptr = 0;
 294     errno = ERRNO_SMTPFORMAT;
 295     return FALSE;
 296     }
 297
 298   /* Loop to cover the read getting interrupted. */
 299
 300   for (;;)
 301     {
 302     char *rc;
 303     int save_errno;
 304
 305     *readptr = 0;           /* In case nothing gets read */
 306     sigalrm_seen = FALSE;
 307     ALARM(timeout);
 308     rc = Ufgets(readptr, size-1, f);
 309     save_errno = errno;
 310     ALARM_CLR(0);
 311     errno = save_errno;
 312
 313     if (rc != NULL) break;  /* A line has been read */
 314
 315     /* Handle timeout; must do this first because it uses EINTR */
 316
 317     if (sigalrm_seen) errno = ETIMEDOUT;
 318
 319     /* If some other interrupt arrived, just retry. We presume this to be rare,
 320     but it can happen (e.g. the SIGUSR1 signal sent by exiwhat causes
 321     read() to exit). */
 322
 323     else if (errno == EINTR)
 324       {
 325       DEBUG(D_transport) debug_printf("EINTR while reading LMTP response\n");
 326       continue;
 327       }
 328
 329     /* Handle other errors, including EOF; ensure buffer is completely empty. */
 330
 331     buffer[0] = 0;
 332     return FALSE;
 333     }
 334
 335   /* Adjust size in case we have to read another line, and adjust the
 336   count to be the length of the line we are about to inspect. */
 337
 338   count = Ustrlen(readptr);
 339   size -= count;
 340   count += readptr - ptr;
 341
 342   /* See if the final two characters in the buffer are \r\n. If not, we
 343   have to read some more. At least, that is what we should do on a strict
 344   interpretation of the RFC. But accept LF as well, as we do for SMTP. */
 345
 346   if (ptr[count-1] != '\n')
 347     {
 348     DEBUG(D_transport)
 349       {
 350       debug_printf("LMTP input line incomplete in one buffer:\n  ");
 351       for (int i = 0; i < count; i++)
 352         {
 353         int c = (ptr[i]);
 354         if (mac_isprint(c)) debug_printf("%c", c); else debug_printf("<%d>", c);
 355         }
 356       debug_printf("\n");
 357       }
 358     readptr = ptr + count;
 359     continue;
 360     }
 361
 362   /* Remove any whitespace at the end of the buffer. This gets rid of CR, LF
 363   etc. at the end. Show it, if debugging, formatting multi-line responses. */
 364
 365   while (count > 0 && isspace(ptr[count-1])) count--;
 366   ptr[count] = 0;
 367
 368   DEBUG(D_transport|D_v)
 369     {
 370     uschar *s = ptr;
 371     uschar *t = ptr;
 372     while (*t != 0)
 373       {
 374       while (*t != 0 && *t != '\n') t++;
 375       debug_printf("  %s %*s\n", (s == ptr)? "LMTP<<" : "      ",
 376         (int)(t-s), s);
 377       if (*t == 0) break;
 378       s = t = t + 1;
 379       }
 380     }
 381
 382   /* Check the format of the response: it must start with three digits; if
 383   these are followed by a space or end of line, the response is complete. If
 384   they are followed by '-' this is a multi-line response and we must look for
 385   another line until the final line is reached. The only use made of multi-line
 386   responses is to pass them back as error messages. We therefore just
 387   concatenate them all within the buffer, which should be large enough to
 388   accept any reasonable number of lines. A multiline response may already
 389   have been read in one go - hence the loop here. */
 390
 391   for(;;)
 392     {
 393     uschar *p;
 394     if (count < 3 ||
 395        !isdigit(ptr[0]) ||
 396        !isdigit(ptr[1]) ||
 397        !isdigit(ptr[2]) ||
 398        (ptr[3] != '-' && ptr[3] != ' ' && ptr[3] != 0))
 399       {
 400       errno = ERRNO_SMTPFORMAT;    /* format error */
 401       return FALSE;
 402       }
 403
 404     /* If a single-line response, exit the loop */
 405
 406     if (ptr[3] != '-') break;
 407
 408     /* For a multi-line response see if the next line is already read, and if
 409     so, stay in this loop to check it. */
 410
 411     p = ptr + 3;
 412     while (*(++p) != 0)
 413       {
 414       if (*p == '\n')
 415         {
 416         ptr = ++p;
 417         break;
 418         }
 419       }
 420     if (*p == 0) break;   /* No more lines to check */
 421     }
 422
 423   /* End of response. If the last of the lines we are looking at is the final
 424   line, we are done. Otherwise more data has to be read. */
 425
 426   if (ptr[3] != '-') break;
 427
 428   /* Move the reading pointer upwards in the buffer and insert \n in case this
 429   is an error message that subsequently gets printed. Set the scanning pointer
 430   to the reading pointer position. */
 431
 432   ptr += count;
 433   *ptr++ = '\n';
 434   size--;
 435   readptr = ptr;
 436   }
 437
 438 /* Return a value that depends on the LMTP return code. Ensure that errno is
 439 zero, because the caller of this function looks at errno when FALSE is
 440 returned, to distinguish between an unexpected return code and other errors
 441 such as timeouts, lost connections, etc. */
 442
 443 errno = 0;
 444 return buffer[0] == okdigit;
 445 }
 446
 447
 448
 449
 450
 451
 452 /*************************************************
 453 *              Main entry point                  *
 454 *************************************************/
 455
 456 /* See local README for interface details. For setup-errors, this transport
 457 returns FALSE, indicating that the first address has the status for all; in
 458 normal cases it returns TRUE, indicating that each address has its own status
 459 set. */
 460
 461 BOOL
 462 lmtp_transport_entry(
 463   transport_instance *tblock,      /* data for this instantiation */
 464   address_item *addrlist)          /* address(es) we are working on */
 465 {
 466 pid_t pid = 0;
 467 FILE *out;
 468 lmtp_transport_options_block *ob =
 469   (lmtp_transport_options_block *)(tblock->options_block);
 470 struct sockaddr_un sockun;         /* don't call this "sun" ! */
 471 int timeout = ob->timeout;
 472 int fd_in = -1, fd_out = -1;
 473 int code, save_errno;
 474 BOOL send_data;
 475 BOOL yield = FALSE;
 476 uschar *igquotstr = US"";
 477 uschar *sockname = NULL;
 478 const uschar **argv;
 479 uschar buffer[256];
 480
 481 DEBUG(D_transport) debug_printf("%s transport entered\n", tblock->name);
 482
 483 /* Initialization ensures that either a command or a socket is specified, but
 484 not both. When a command is specified, call the common function for creating an
 485 argument list and expanding the items. */
 486
 487 if (ob->cmd)
 488   {
 489   DEBUG(D_transport) debug_printf("using command %s\n", ob->cmd);
 490   sprintf(CS buffer, "%.50s transport", tblock->name);
 491   if (!transport_set_up_command(&argv, ob->cmd, TRUE, PANIC, addrlist, buffer,
 492        NULL))
 493     return FALSE;
 494
 495   /* If the -N option is set, can't do any more. Presume all has gone well. */
 496   if (f.dont_deliver)
 497     goto MINUS_N;
 498
 499 /* As this is a local transport, we are already running with the required
 500 uid/gid and current directory. Request that the new process be a process group
 501 leader, so we can kill it and all its children on an error. */
 502
 503   if ((pid = child_open(USS argv, NULL, 0, &fd_in, &fd_out, TRUE,
 504                         US"lmtp-tpt-cmd")) < 0)
 505     {
 506     addrlist->message = string_sprintf(
 507       "Failed to create child process for %s transport: %s", tblock->name,
 508         strerror(errno));
 509     return FALSE;
 510     }
 511   }
 512
 513 /* When a socket is specified, expand the string and create a socket. */
 514
 515 else
 516   {
 517   DEBUG(D_transport) debug_printf("using socket %s\n", ob->skt);
 518   if (!(sockname = expand_string(ob->skt)))
 519     {
 520     addrlist->message = string_sprintf("Expansion of \"%s\" (socket setting "
 521       "for %s transport) failed: %s", ob->skt, tblock->name,
 522       expand_string_message);
 523     return FALSE;
 524     }
 525   if ((fd_in = fd_out = socket(PF_UNIX, SOCK_STREAM, 0)) == -1)
 526     {
 527     addrlist->message = string_sprintf(
 528       "Failed to create socket %s for %s transport: %s",
 529         ob->skt, tblock->name, strerror(errno));
 530     return FALSE;
 531     }
 532
 533   /* If the -N option is set, can't do any more. Presume all has gone well. */
 534   if (f.dont_deliver)
 535     goto MINUS_N;
 536
 537   sockun.sun_family = AF_UNIX;
 538   sprintf(sockun.sun_path, "%.*s", (int)(sizeof(sockun.sun_path)-1), sockname);
 539   if(connect(fd_out, (struct sockaddr *)(&sockun), sizeof(sockun)) == -1)
 540     {
 541     addrlist->message = string_sprintf(
 542       "Failed to connect to socket %s for %s transport: %s",
 543         sockun.sun_path, tblock->name, strerror(errno));
 544     return FALSE;
 545     }
 546   }
 547
 548
 549 /* Make the output we are going to read into a file. */
 550
 551 out = fdopen(fd_out, "rb");
 552
 553 /* Now we must implement the LMTP protocol. It is like SMTP, except that after
 554 the end of the message, a return code for every accepted RCPT TO is sent. This
 555 allows for message+recipient checks after the message has been received. */
 556
 557 /* First thing is to wait for an initial greeting. */
 558
 559 Ustrcpy(big_buffer, US"initial connection");
 560 if (!lmtp_read_response(out, buffer, sizeof(buffer), '2',
 561   timeout)) goto RESPONSE_FAILED;
 562
 563 /* Next, we send a LHLO command, and expect a positive response */
 564
 565 if (!lmtp_write_command(fd_in, "%s %s\r\n", "LHLO",
 566   primary_hostname)) goto WRITE_FAILED;
 567
 568 if (!lmtp_read_response(out, buffer, sizeof(buffer), '2',
 569      timeout)) goto RESPONSE_FAILED;
 570
 571 /* If the ignore_quota option is set, note whether the server supports the
 572 IGNOREQUOTA option, and if so, set an appropriate addition for RCPT. */
 573
 574 if (ob->ignore_quota)
 575   igquotstr = (pcre_exec(regex_IGNOREQUOTA, NULL, CS buffer,
 576     Ustrlen(CS buffer), 0, PCRE_EOPT, NULL, 0) >= 0)? US" IGNOREQUOTA" : US"";
 577
 578 /* Now the envelope sender */
 579
 580 if (!lmtp_write_command(fd_in, "MAIL FROM:<%s>\r\n", return_path))
 581   goto WRITE_FAILED;
 582
 583 if (!lmtp_read_response(out, buffer, sizeof(buffer), '2', timeout))
 584   {
 585   if (errno == 0 && buffer[0] == '4')
 586     {
 587     errno = ERRNO_MAIL4XX;
 588     addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
 589     }
 590   goto RESPONSE_FAILED;
 591   }
 592
 593 /* Next, we hand over all the recipients. Some may be permanently or
 594 temporarily rejected; others may be accepted, for now. */
 595
 596 send_data = FALSE;
 597 for (address_item * addr = addrlist; addr; addr = addr->next)
 598   {
 599   if (!lmtp_write_command(fd_in, "RCPT TO:<%s>%s\r\n",
 600        transport_rcpt_address(addr, tblock->rcpt_include_affixes), igquotstr))
 601     goto WRITE_FAILED;
 602   if (lmtp_read_response(out, buffer, sizeof(buffer), '2', timeout))
 603     {
 604     send_data = TRUE;
 605     addr->transport_return = PENDING_OK;
 606     }
 607   else
 608     {
 609     if (errno != 0 || buffer[0] == 0) goto RESPONSE_FAILED;
 610     addr->message = string_sprintf("LMTP error after %s: %s", big_buffer,
 611       string_printing(buffer));
 612     setflag(addr, af_pass_message);   /* Allow message to go to user */
 613     if (buffer[0] == '5') addr->transport_return = FAIL; else
 614       {
 615       addr->basic_errno = ERRNO_RCPT4XX;
 616       addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
 617       }
 618     }
 619   }
 620
 621 /* Now send the text of the message if there were any good recipients. */
 622
 623 if (send_data)
 624   {
 625   BOOL ok;
 626   transport_ctx tctx = {
 627     {fd_in},
 628     tblock,
 629     addrlist,
 630     US".", US"..",
 631     ob->options
 632   };
 633
 634   if (!lmtp_write_command(fd_in, "DATA\r\n")) goto WRITE_FAILED;
 635   if (!lmtp_read_response(out, buffer, sizeof(buffer), '3', timeout))
 636     {
 637     if (errno == 0 && buffer[0] == '4')
 638       {
 639       errno = ERRNO_DATA4XX;
 640       addrlist->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
 641       }
 642     goto RESPONSE_FAILED;
 643     }
 644
 645   sigalrm_seen = FALSE;
 646   transport_write_timeout = timeout;
 647   Ustrcpy(big_buffer, US"sending data block");   /* For error messages */
 648   DEBUG(D_transport|D_v)
 649     debug_printf("  LMTP>> writing message and terminating \".\"\n");
 650
 651   transport_count = 0;
 652   ok = transport_write_message(&tctx, 0);
 653
 654   /* Failure can either be some kind of I/O disaster (including timeout),
 655   or the failure of a transport filter or the expansion of added headers. */
 656
 657   if (!ok)
 658     {
 659     buffer[0] = 0;              /* There hasn't been a response */
 660     goto RESPONSE_FAILED;
 661     }
 662
 663   Ustrcpy(big_buffer, US"end of data");   /* For error messages */
 664
 665   /* We now expect a response for every address that was accepted above,
 666   in the same order. For those that get a response, their status is fixed;
 667   any that are accepted have been handed over, even if later responses crash -
 668   at least, that's how I read RFC 2033. */
 669
 670   for (address_item * addr = addrlist; addr; addr = addr->next)
 671     {
 672     if (addr->transport_return != PENDING_OK) continue;
 673
 674     if (lmtp_read_response(out, buffer, sizeof(buffer), '2', timeout))
 675       {
 676       addr->transport_return = OK;
 677       if (LOGGING(smtp_confirmation))
 678         {
 679         const uschar *s = string_printing(buffer);
 680         /* de-const safe here as string_printing known to have alloc'n'copied */
 681         addr->message = (s == buffer)? US string_copy(s) : US s;
 682         }
 683       }
 684     /* If the response has failed badly, use it for all the remaining pending
 685     addresses and give up. */
 686
 687     else if (errno != 0 || buffer[0] == 0)
 688       {
 689       save_errno = errno;
 690       check_response(&save_errno, addr->more_errno, buffer, &code,
 691         &(addr->message));
 692       addr->transport_return = (code == '5')? FAIL : DEFER;
 693       for (address_item * a = addr->next; a; a = a->next)
 694         {
 695         if (a->transport_return != PENDING_OK) continue;
 696         a->basic_errno = addr->basic_errno;
 697         a->message = addr->message;
 698         a->transport_return = addr->transport_return;
 699         }
 700       break;
 701       }
 702
 703     /* Otherwise, it's an LMTP error code return for one address */
 704
 705     else
 706       {
 707       if (buffer[0] == '4')
 708         {
 709         addr->basic_errno = ERRNO_DATA4XX;
 710         addr->more_errno |= ((buffer[1] - '0')*10 + buffer[2] - '0') << 8;
 711         }
 712       addr->message = string_sprintf("LMTP error after %s: %s", big_buffer,
 713         string_printing(buffer));
 714       addr->transport_return = (buffer[0] == '5')? FAIL : DEFER;
 715       setflag(addr, af_pass_message);   /* Allow message to go to user */
 716       }
 717     }
 718   }
 719
 720 /* The message transaction has completed successfully - this doesn't mean that
 721 all the addresses have necessarily been transferred, but each has its status
 722 set, so we change the yield to TRUE. */
 723
 724 yield = TRUE;
 725 (void) lmtp_write_command(fd_in, "QUIT\r\n");
 726 (void) lmtp_read_response(out, buffer, sizeof(buffer), '2', 1);
 727
 728 goto RETURN;
 729
 730
 731 /* Come here if any call to read_response, other than a response after the data
 732 phase, failed. Put the error in the top address - this will be replicated
 733 because the yield is still FALSE. (But omit ETIMEDOUT, as there will already be
 734 a suitable message.) Analyse the error, and if if isn't too bad, send a QUIT
 735 command. Wait for the response with a short timeout, so we don't wind up this
 736 process before the far end has had time to read the QUIT. */
 737
 738 RESPONSE_FAILED:
 739
 740 save_errno = errno;
 741 if (errno != ETIMEDOUT && errno != 0) addrlist->basic_errno = errno;
 742 addrlist->message = NULL;
 743
 744 if (check_response(&save_errno, addrlist->more_errno,
 745     buffer, &code, &(addrlist->message)))
 746   {
 747   (void) lmtp_write_command(fd_in, "QUIT\r\n");
 748   (void) lmtp_read_response(out, buffer, sizeof(buffer), '2', 1);
 749   }
 750
 751 addrlist->transport_return = (code == '5')? FAIL : DEFER;
 752 if (code == '4' && save_errno > 0)
 753   addrlist->message = string_sprintf("%s: %s", addrlist->message,
 754     strerror(save_errno));
 755 goto KILL_AND_RETURN;
 756
 757 /* Come here if there are errors during writing of a command or the message
 758 itself. This error will be applied to all the addresses. */
 759
 760 WRITE_FAILED:
 761
 762 addrlist->transport_return = PANIC;
 763 addrlist->basic_errno = errno;
 764 if (errno == ERRNO_CHHEADER_FAIL)
 765   addrlist->message =
 766     string_sprintf("Failed to expand headers_add or headers_remove: %s",
 767       expand_string_message);
 768 else if (errno == ERRNO_FILTER_FAIL)
 769   addrlist->message = US"Filter process failure";
 770 else if (errno == ERRNO_WRITEINCOMPLETE)
 771   addrlist->message = US"Failed repeatedly to write data";
 772 else if (errno == ERRNO_SMTPFORMAT)
 773   addrlist->message = US"overlong LMTP command generated";
 774 else
 775   addrlist->message = string_sprintf("Error %d", errno);
 776
 777 /* Come here after errors. Kill off the process. */
 778
 779 KILL_AND_RETURN:
 780
 781 if (pid > 0) killpg(pid, SIGKILL);
 782
 783 /* Come here from all paths after the subprocess is created. Wait for the
 784 process, but with a timeout. */
 785
 786 RETURN:
 787
 788 (void)child_close(pid, timeout);
 789
 790 if (fd_in >= 0) (void)close(fd_in);
 791 if (fd_out >= 0) (void)fclose(out);
 792
 793 DEBUG(D_transport)
 794   debug_printf("%s transport yields %d\n", tblock->name, yield);
 795
 796 return yield;
 797
 798
 799 MINUS_N:
 800   DEBUG(D_transport)
 801     debug_printf("*** delivery by %s transport bypassed by -N option",
 802       tblock->name);
 803   addrlist->transport_return = OK;
 804   return FALSE;
 805 }
 806
 807 #endif  /*!MACRO_PREDEF*/
 808 /* End of transport/lmtp.c */