5
/* Postfix local delivery via LMTP
7
/* \fBlmtp\fR [generic Postfix daemon options]
9
/* The LMTP client processes message delivery requests from
10
/* the queue manager. Each request specifies a queue file, a sender
11
/* address, a domain or host to deliver to, and recipient information.
12
/* This program expects to be run from the \fBmaster\fR(8) process
15
/* The LMTP client updates the queue file and marks recipients
16
/* as finished, or it informs the queue manager that delivery should
17
/* be tried again at a later time. Delivery status reports are sent
18
/* to the \fBbounce\fR(8), \fBdefer\fR(8) or \fBtrace\fR(8) daemon as
21
/* The LMTP client connects to the destination specified in the message
22
/* delivery request. The destination, usually specified in the Postfix
23
/* \fBtransport\fR(5) table, has the form:
24
/* .IP \fBunix\fR:\fIpathname\fR
25
/* Connect to the local UNIX-domain server that is bound to the specified
26
/* \fIpathname\fR. If the process runs chrooted, an absolute pathname
27
/* is interpreted relative to the changed root directory.
28
/* .IP "\fBinet\fR:\fIhost\fR, \fBinet\fB:\fIhost\fR:\fIport\fR (symbolic host)"
29
/* .IP "\fBinet\fR:[\fIaddr\fR], \fBinet\fR:[\fIaddr\fR]:\fIport\fR (numeric host)"
30
/* Connect to the specified IPV4 TCP port on the specified local or
31
/* remote host. If no port is specified, connect to the port defined as
32
/* \fBlmtp\fR in \fBservices\fR(4).
33
/* If no such service is found, the \fBlmtp_tcp_port\fR configuration
34
/* parameter (default value of 24) will be used.
36
/* The LMTP client does not perform MX (mail exchanger) lookups since
37
/* those are defined only for mail delivery via SMTP.
39
/* If neither \fBunix:\fR nor \fBinet:\fR are specified, \fBinet:\fR
44
/* The LMTP client is moderately security-sensitive. It talks to LMTP
45
/* servers and to DNS servers on the network. The LMTP client can be
46
/* run chrooted at fixed low privilege.
48
/* RFC 821 (SMTP protocol)
49
/* RFC 1651 (SMTP service extensions)
50
/* RFC 1652 (8bit-MIME transport)
51
/* RFC 1870 (Message Size Declaration)
52
/* RFC 2033 (LMTP protocol)
53
/* RFC 2554 (AUTH command)
54
/* RFC 2821 (SMTP protocol)
55
/* RFC 2920 (SMTP Pipelining)
57
/* Problems and transactions are logged to \fBsyslogd\fR(8).
58
/* Corrupted message files are marked so that the queue manager can
59
/* move them to the \fBcorrupt\fR queue for further inspection.
61
/* Depending on the setting of the \fBnotify_classes\fR parameter,
62
/* the postmaster is notified of bounces, protocol problems, and of
64
/* CONFIGURATION PARAMETERS
67
/* Changes to \fBmain.cf\fR are picked up automatically, as lmtp(8)
68
/* processes run for only a limited amount of time. Use the command
69
/* "\fBpostfix reload\fR" to speed up a change.
71
/* The text below provides only a parameter summary. See
72
/* postconf(5) for more details including examples.
73
/* COMPATIBILITY CONTROLS
76
/* .IP "\fBlmtp_skip_quit_response (no)\fR"
77
/* Wait for the response to the LMTP QUIT command.
78
/* TROUBLE SHOOTING CONTROLS
81
/* .IP "\fBdebug_peer_level (2)\fR"
82
/* The increment in verbose logging level when a remote client or
83
/* server matches a pattern in the debug_peer_list parameter.
84
/* .IP "\fBdebug_peer_list (empty)\fR"
85
/* Optional list of remote client or server hostname or network
86
/* address patterns that cause the verbose logging level to increase
87
/* by the amount specified in $debug_peer_level.
88
/* .IP "\fBerror_notice_recipient (postmaster)\fR"
89
/* The recipient of postmaster notifications about mail delivery
90
/* problems that are caused by policy, resource, software or protocol
92
/* .IP "\fBnotify_classes (resource, software)\fR"
93
/* The list of error classes that are reported to the postmaster.
94
/* EXTERNAL CONTENT INSPECTION CONTROLS
97
/* Available in Postfix version 2.1 and later:
98
/* .IP "\fBlmtp_send_xforward_command (no)\fR"
99
/* Send an XFORWARD command to the LMTP server when the LMTP LHLO
100
/* server response announces XFORWARD support.
101
/* SASL AUTHENTICATION CONTROLS
104
/* .IP "\fBlmtp_sasl_auth_enable (no)\fR"
105
/* Enable SASL authentication in the Postfix LMTP client.
106
/* .IP "\fBlmtp_sasl_password_maps (empty)\fR"
107
/* Optional LMTP client lookup tables with one username:password entry
108
/* per host or domain.
109
/* .IP "\fBlmtp_sasl_security_options (noplaintext, noanonymous)\fR"
110
/* What authentication mechanisms the Postfix LMTP client is allowed
112
/* RESOURCE AND RATE CONTROLS
115
/* In the text below, \fItransport\fR is the name
116
/* of the service as specified in the \fBmaster.cf\fR file.
117
/* .IP "\fBlmtp_cache_connection (yes)\fR"
118
/* Keep Postfix LMTP client connections open for up to $max_idle
120
/* .IP "\fItransport_\fBdestination_concurrency_limit ($default_destination_concurrency_limit)\fR"
121
/* Limit the number of parallel deliveries to the same destination
122
/* via this mail delivery transport.
123
/* .IP "\fItransport_\fBdestination_recipient_limit ($default_destination_recipient_limit)\fR"
124
/* Limit the number of recipients per message delivery via this mail
125
/* delivery transport.
127
/* This parameter becomes significant if the LMTP client is used
128
/* for local delivery. Some LMTP servers can optimize delivery of
129
/* the same message to multiple recipients. The default limit for
130
/* local mail delivery is 1.
132
/* Setting this parameter to 0 will lead to an unbounded number of
133
/* recipients per delivery. However, this could be risky since it may
134
/* make the machine vulnerable to running out of resources if messages
135
/* are encountered with an inordinate number of recipients. Exercise
136
/* care when setting this parameter.
137
/* .IP "\fBlmtp_connect_timeout (0s)\fR"
138
/* The LMTP client time limit for completing a TCP connection, or
139
/* zero (use the operating system built-in time limit).
140
/* .IP "\fBlmtp_lhlo_timeout (300s)\fR"
141
/* The LMTP client time limit for receiving the LMTP greeting
143
/* .IP "\fBlmtp_xforward_timeout (300s)\fR"
144
/* The LMTP client time limit for sending the XFORWARD command, and
145
/* for receiving the server response.
146
/* .IP "\fBlmtp_mail_timeout (300s)\fR"
147
/* The LMTP client time limit for sending the MAIL FROM command, and
148
/* for receiving the server response.
149
/* .IP "\fBlmtp_rcpt_timeout (300s)\fR"
150
/* The LMTP client time limit for sending the RCPT TO command, and
151
/* for receiving the server response.
152
/* .IP "\fBlmtp_data_init_timeout (120s)\fR"
153
/* The LMTP client time limit for sending the LMTP DATA command, and
154
/* for receiving the server response.
155
/* .IP "\fBlmtp_data_xfer_timeout (180s)\fR"
156
/* The LMTP client time limit for sending the LMTP message content.
157
/* .IP "\fBlmtp_data_done_timeout (600s)\fR"
158
/* The LMTP client time limit for sending the LMTP ".", and for
159
/* receiving the server response.
160
/* .IP "\fBlmtp_rset_timeout (120s)\fR"
161
/* The LMTP client time limit for sending the RSET command, and for
162
/* receiving the server response.
163
/* .IP "\fBlmtp_quit_timeout (300s)\fR"
164
/* The LMTP client time limit for sending the QUIT command, and for
165
/* receiving the server response.
166
/* MISCELLANEOUS CONTROLS
169
/* .IP "\fBconfig_directory (see 'postconf -d' output)\fR"
170
/* The default location of the Postfix main.cf and master.cf
171
/* configuration files.
172
/* .IP "\fBdaemon_timeout (18000s)\fR"
173
/* How much time a Postfix daemon process may take to handle a
174
/* request before it is terminated by a built-in watchdog timer.
175
/* .IP "\fBdisable_dns_lookups (no)\fR"
176
/* Disable DNS lookups in the Postfix SMTP and LMTP clients.
177
/* .IP "\fBipc_timeout (3600s)\fR"
178
/* The time limit for sending or receiving information over an internal
179
/* communication channel.
180
/* .IP "\fBlmtp_tcp_port (24)\fR"
181
/* The default TCP port that the Postfix LMTP client connects to.
182
/* .IP "\fBmax_idle (100s)\fR"
183
/* The maximum amount of time that an idle Postfix daemon process
184
/* waits for the next service request before exiting.
185
/* .IP "\fBmax_use (100)\fR"
186
/* The maximal number of connection requests before a Postfix daemon
187
/* process terminates.
188
/* .IP "\fBprocess_id (read-only)\fR"
189
/* The process ID of a Postfix command or daemon process.
190
/* .IP "\fBprocess_name (read-only)\fR"
191
/* The process name of a Postfix command or daemon process.
192
/* .IP "\fBqueue_directory (see 'postconf -d' output)\fR"
193
/* The location of the Postfix top-level queue directory.
194
/* .IP "\fBsyslog_facility (mail)\fR"
195
/* The syslog facility of Postfix logging.
196
/* .IP "\fBsyslog_name (postfix)\fR"
197
/* The mail system name that is prepended to the process name in syslog
198
/* records, so that "smtpd" becomes, for example, "postfix/smtpd".
200
/* bounce(8), delivery status reports
201
/* qmgr(8), queue manager
202
/* postconf(5), configuration parameters
203
/* services(4), Internet services and aliases
204
/* master(8), process manager
205
/* syslogd(8), system logging
209
/* Use "\fBpostconf readme_directory\fR" or
210
/* "\fBpostconf html_directory\fR" to locate this information.
213
/* LMTP_README, Postfix LMTP client howto
214
/* VIRTUAL_README, virtual delivery agent howto
218
/* The Secure Mailer license must be distributed with this software.
221
/* IBM T.J. Watson Research
223
/* Yorktown Heights, NY 10598, USA
225
/* Alterations for LMTP by:
226
/* Philip A. Prindeville
230
/* Additional work on LMTP by:
232
/* University of Texas at Dallas
233
/* P.O. Box 830688, MC34
234
/* Richardson, TX 75083, USA
237
/* System library. */
239
#include <sys_defs.h>
246
/* Utility library. */
250
#include <mymalloc.h>
251
#include <name_mask.h>
252
#include <split_at.h>
254
/* Global library. */
256
#include <deliver_request.h>
257
#include <mail_queue.h>
258
#include <mail_params.h>
259
#include <mail_conf.h>
260
#include <debug_peer.h>
261
#include <mail_error.h>
262
#include <flush_clnt.h>
264
/* Single server skeleton. */
266
#include <mail_server.h>
268
/* Application-specific. */
271
#include "lmtp_sasl.h"
274
* Tunable parameters. These have compiled-in defaults that can be overruled
275
* by settings in the global Postfix configuration file.
277
int var_lmtp_tcp_port;
278
int var_lmtp_conn_tmout;
279
int var_lmtp_rset_tmout;
280
int var_lmtp_lhlo_tmout;
281
int var_lmtp_xfwd_tmout;
282
int var_lmtp_mail_tmout;
283
int var_lmtp_rcpt_tmout;
284
int var_lmtp_data0_tmout;
285
int var_lmtp_data1_tmout;
286
int var_lmtp_data2_tmout;
287
int var_lmtp_quit_tmout;
288
int var_lmtp_cache_conn;
289
int var_lmtp_skip_quit_resp;
290
char *var_notify_classes;
291
char *var_error_rcpt;
292
char *var_lmtp_sasl_opts;
293
char *var_lmtp_sasl_passwd;
294
bool var_lmtp_sasl_enable;
295
bool var_lmtp_send_xforward;
300
* lmtp_errno is set by the address lookup routines and by the connection
301
* management routines.
303
* state is global for the connection caching to work.
306
static LMTP_STATE *state = 0;
308
/* deliver_message - deliver message with extreme prejudice */
310
static int deliver_message(DELIVER_REQUEST *request, char **unused_argv)
312
char *myname = "deliver_message";
317
msg_info("%s: from %s", myname, request->sender);
322
if (request->rcpt_list.len <= 0)
323
msg_fatal("%s: recipient count: %d", myname, request->rcpt_list.len);
326
* Initialize. Bundle all information about the delivery request, so that
327
* we can produce understandable diagnostics when something goes wrong
328
* many levels below. The alternative would be to make everything global.
330
* Note: `state' was made global (to this file) so that we can cache
331
* connections and so that we can close a cached connection via the
332
* MAIL_SERVER_EXIT function (cleanup). The alloc for `state' is
333
* performed in the MAIL_SERVER_PRE_INIT function (pre_init).
336
why = vstring_alloc(100);
337
state->request = request;
338
state->src = request->fp;
341
* See if we can reuse an existing connection.
343
if (state->session != 0) {
346
* Disconnect if we're going to a different destination. Discard
347
* transcript and status information for sending QUIT.
349
* XXX Should transform nexthop into canonical form (unix:/path or
350
* inet:host:port) before doing connection cache lookup. See also the
351
* connection cache updating code in lmtp_connect.c.
353
if (strcasecmp(state->session->dest, request->nexthop) != 0) {
355
lmtp_chat_reset(state);
356
state->session = lmtp_session_free(state->session);
358
if (var_lmtp_sasl_enable)
359
lmtp_sasl_cleanup(state);
364
* Disconnect if RSET can't be sent over an existing connection.
365
* Discard transcript and status information for sending RSET.
367
else if (lmtp_rset(state) != 0) {
368
lmtp_chat_reset(state);
369
state->session = lmtp_session_free(state->session);
371
if (var_lmtp_sasl_enable)
372
lmtp_sasl_cleanup(state);
377
* Ready to go with another load. The reuse counter is logged for
378
* statistical analysis purposes. Given the Postfix architecture,
379
* connection cacheing makes sense only for dedicated transports.
380
* Logging the reuse count can help to convince people.
385
msg_info("%s: reusing (count %d) session with: %s",
386
myname, state->reuse, state->session->host);
391
* See if we need to establish an LMTP connection.
393
if (state->session == 0) {
396
* Bounce or defer the recipients if no connection can be made.
398
if ((state->session = lmtp_connect(request->nexthop, why)) == 0) {
399
lmtp_site_fail(state, lmtp_errno == LMTP_RETRY ? 450 : 550,
400
"%s", vstring_str(why));
404
* Bounce or defer the recipients if the LMTP handshake fails.
406
else if (lmtp_lhlo(state) != 0) {
407
state->session = lmtp_session_free(state->session);
409
if (var_lmtp_sasl_enable)
410
lmtp_sasl_cleanup(state);
415
* Congratulations. We just established a new LMTP connection.
422
* If a session exists, deliver this message to all requested recipients.
424
if (state->session != 0)
428
* Optionally, notify the postmaster of problems with establishing a
429
* session or with delivering mail.
431
if (state->history != 0
432
&& (state->error_mask & name_mask(VAR_NOTIFY_CLASSES, mail_error_masks,
433
var_notify_classes)))
434
lmtp_chat_notify(state);
437
* Disconnect if we're not caching connections. The pipelined protocol
438
* state machine knows if it should have sent a QUIT command. Do not
439
* cache a broken connection.
441
if (state->session != 0
442
&& (!var_lmtp_cache_conn
443
|| vstream_ferror(state->session->stream)
444
|| vstream_feof(state->session->stream)))
445
state->session = lmtp_session_free(state->session);
451
result = state->status;
452
lmtp_chat_reset(state);
455
* XXX State persists until idle timeout, but these fields will be
456
* dangling pointers. Nuke them.
464
/* lmtp_service - perform service for client */
466
static void lmtp_service(VSTREAM *client_stream, char *unused_service, char **argv)
468
DELIVER_REQUEST *request;
472
* Sanity check. This service takes no command-line arguments.
475
msg_fatal("unexpected command-line argument: %s", argv[0]);
478
* This routine runs whenever a client connects to the UNIX-domain socket
479
* dedicated to remote LMTP delivery service. What we see below is a
480
* little protocol to (1) tell the queue manager that we are ready, (2)
481
* read a request from the queue manager, and (3) report the completion
482
* status of that request. All connection-management stuff is handled by
483
* the common code in single_server.c.
485
if ((request = deliver_request_read(client_stream)) != 0) {
486
status = deliver_message(request, argv);
487
deliver_request_done(client_stream, request, status);
491
/* post_init - post-jail initialization */
493
static void post_init(char *unused_name, char **unused_argv)
495
state = lmtp_state_alloc();
498
/* pre_init - pre-jail initialization */
500
static void pre_init(char *unused_name, char **unused_argv)
503
if (var_lmtp_sasl_enable)
505
lmtp_sasl_initialize();
507
msg_warn("%s is true, but SASL support is not compiled in",
508
VAR_LMTP_SASL_ENABLE);
517
/* cleanup - close any open connections, etc. */
519
static void cleanup(void)
521
if (state->session != 0) {
523
lmtp_chat_reset(state);
524
state->session = lmtp_session_free(state->session);
526
msg_info("cleanup: just closed down session");
528
lmtp_state_free(state);
530
if (var_lmtp_sasl_enable)
535
/* pre_accept - see if tables have changed */
537
static void pre_accept(char *unused_name, char **unused_argv)
541
if ((table = dict_changed_name()) != 0) {
542
msg_info("table %s has changed -- restarting", table);
548
/* main - pass control to the single-threaded skeleton */
550
int main(int argc, char **argv)
552
static CONFIG_STR_TABLE str_table[] = {
553
VAR_NOTIFY_CLASSES, DEF_NOTIFY_CLASSES, &var_notify_classes, 0, 0,
554
VAR_ERROR_RCPT, DEF_ERROR_RCPT, &var_error_rcpt, 1, 0,
555
VAR_LMTP_SASL_PASSWD, DEF_LMTP_SASL_PASSWD, &var_lmtp_sasl_passwd, 0, 0,
556
VAR_LMTP_SASL_OPTS, DEF_LMTP_SASL_OPTS, &var_lmtp_sasl_opts, 0, 0,
559
static CONFIG_INT_TABLE int_table[] = {
560
VAR_LMTP_TCP_PORT, DEF_LMTP_TCP_PORT, &var_lmtp_tcp_port, 0, 0,
563
static CONFIG_TIME_TABLE time_table[] = {
564
VAR_LMTP_CONN_TMOUT, DEF_LMTP_CONN_TMOUT, &var_lmtp_conn_tmout, 0, 0,
565
VAR_LMTP_RSET_TMOUT, DEF_LMTP_RSET_TMOUT, &var_lmtp_rset_tmout, 1, 0,
566
VAR_LMTP_LHLO_TMOUT, DEF_LMTP_LHLO_TMOUT, &var_lmtp_lhlo_tmout, 1, 0,
567
VAR_LMTP_XFWD_TMOUT, DEF_LMTP_XFWD_TMOUT, &var_lmtp_xfwd_tmout, 1, 0,
568
VAR_LMTP_MAIL_TMOUT, DEF_LMTP_MAIL_TMOUT, &var_lmtp_mail_tmout, 1, 0,
569
VAR_LMTP_RCPT_TMOUT, DEF_LMTP_RCPT_TMOUT, &var_lmtp_rcpt_tmout, 1, 0,
570
VAR_LMTP_DATA0_TMOUT, DEF_LMTP_DATA0_TMOUT, &var_lmtp_data0_tmout, 1, 0,
571
VAR_LMTP_DATA1_TMOUT, DEF_LMTP_DATA1_TMOUT, &var_lmtp_data1_tmout, 1, 0,
572
VAR_LMTP_DATA2_TMOUT, DEF_LMTP_DATA2_TMOUT, &var_lmtp_data2_tmout, 1, 0,
573
VAR_LMTP_QUIT_TMOUT, DEF_LMTP_QUIT_TMOUT, &var_lmtp_quit_tmout, 1, 0,
576
static CONFIG_BOOL_TABLE bool_table[] = {
577
VAR_LMTP_CACHE_CONN, DEF_LMTP_CACHE_CONN, &var_lmtp_cache_conn,
578
VAR_LMTP_SKIP_QUIT_RESP, DEF_LMTP_SKIP_QUIT_RESP, &var_lmtp_skip_quit_resp,
579
VAR_LMTP_SASL_ENABLE, DEF_LMTP_SASL_ENABLE, &var_lmtp_sasl_enable,
580
VAR_LMTP_SEND_XFORWARD, DEF_LMTP_SEND_XFORWARD, &var_lmtp_send_xforward,
584
single_server_main(argc, argv, lmtp_service,
585
MAIL_SERVER_INT_TABLE, int_table,
586
MAIL_SERVER_STR_TABLE, str_table,
587
MAIL_SERVER_BOOL_TABLE, bool_table,
588
MAIL_SERVER_TIME_TABLE, time_table,
589
MAIL_SERVER_PRE_INIT, pre_init,
590
MAIL_SERVER_POST_INIT, post_init,
591
MAIL_SERVER_PRE_ACCEPT, pre_accept,
592
MAIL_SERVER_EXIT, cleanup,
added
removed
src/lmtp/lmtp.c
