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/*++
/* NAME
/* error 8
/* SUMMARY
/* Postfix error/retry mail delivery agent
/* SYNOPSIS
/* \fBerror\fR [generic Postfix daemon options]
/* DESCRIPTION
/* The Postfix \fBerror\fR(8) delivery agent processes delivery
/* requests from
/* the queue manager. Each request specifies a queue file, a sender
/* address, the reason for non-delivery (specified as the
/* next-hop destination), and recipient information.
/* The reason may be prefixed with an RFC 3463-compatible detail code;
/* if none is specified a default 4.0.0 or 5.0.0 code is used instead.
/* This program expects to be run from the \fBmaster\fR(8) process
/* manager.
/*
/* Depending on the service name in master.cf, \fBerror\fR
/* or \fBretry\fR, the server bounces or defers all recipients
/* in the delivery request using the "next-hop" information
/* as the reason for non-delivery. The \fBretry\fR service name is
/* supported as of Postfix 2.4.
/*
/* Delivery status reports are sent to the \fBbounce\fR(8),
/* \fBdefer\fR(8) or \fBtrace\fR(8) daemon as appropriate.
/* SECURITY
/* .ad
/* .fi
/* The \fBerror\fR(8) mailer is not security-sensitive. It does not talk
/* to the network, and can be run chrooted at fixed low privilege.
/* STANDARDS
/* RFC 3463 (Enhanced Status Codes)
/* DIAGNOSTICS
/* Problems and transactions are logged to \fBsyslogd\fR(8)
/* or \fBpostlogd\fR(8).
/*
/* Depending on the setting of the \fBnotify_classes\fR parameter,
/* the postmaster is notified of bounces and of other trouble.
/* CONFIGURATION PARAMETERS
/* .ad
/* .fi
/* Changes to \fBmain.cf\fR are picked up automatically as \fBerror\fR(8)
/* processes run for only a limited amount of time. Use the command
/* "\fBpostfix reload\fR" to speed up a change.
/*
/* The text below provides only a parameter summary. See
/* \fBpostconf\fR(5) for more details including examples.
/* .IP "\fB2bounce_notice_recipient (postmaster)\fR"
/* The recipient of undeliverable mail that cannot be returned to
/* the sender.
/* .IP "\fBbounce_notice_recipient (postmaster)\fR"
/* The recipient of postmaster notifications with the message headers
/* of mail that Postfix did not deliver and of SMTP conversation
/* transcripts of mail that Postfix did not receive.
/* .IP "\fBconfig_directory (see 'postconf -d' output)\fR"
/* The default location of the Postfix main.cf and master.cf
/* configuration files.
/* .IP "\fBdaemon_timeout (18000s)\fR"
/* How much time a Postfix daemon process may take to handle a
/* request before it is terminated by a built-in watchdog timer.
/* .IP "\fBdelay_logging_resolution_limit (2)\fR"
/* The maximal number of digits after the decimal point when logging
/* sub-second delay values.
/* .IP "\fBdouble_bounce_sender (double-bounce)\fR"
/* The sender address of postmaster notifications that are generated
/* by the mail system.
/* .IP "\fBipc_timeout (3600s)\fR"
/* The time limit for sending or receiving information over an internal
/* communication channel.
/* .IP "\fBmax_idle (100s)\fR"
/* The maximum amount of time that an idle Postfix daemon process waits
/* for an incoming connection before terminating voluntarily.
/* .IP "\fBmax_use (100)\fR"
/* The maximal number of incoming connections that a Postfix daemon
/* process will service before terminating voluntarily.
/* .IP "\fBnotify_classes (resource, software)\fR"
/* The list of error classes that are reported to the postmaster.
/* .IP "\fBprocess_id (read-only)\fR"
/* The process ID of a Postfix command or daemon process.
/* .IP "\fBprocess_name (read-only)\fR"
/* The process name of a Postfix command or daemon process.
/* .IP "\fBqueue_directory (see 'postconf -d' output)\fR"
/* The location of the Postfix top-level queue directory.
/* .IP "\fBsyslog_facility (mail)\fR"
/* The syslog facility of Postfix logging.
/* .IP "\fBsyslog_name (see 'postconf -d' output)\fR"
/* A prefix that is prepended to the process name in syslog
/* records, so that, for example, "smtpd" becomes "prefix/smtpd".
/* .PP
/* Available in Postfix 3.3 and later:
/* .IP "\fBservice_name (read-only)\fR"
/* The master.cf service name of a Postfix daemon process.
/* SEE ALSO
/* qmgr(8), queue manager
/* bounce(8), delivery status reports
/* discard(8), Postfix discard delivery agent
/* postconf(5), configuration parameters
/* master(5), generic daemon options
/* master(8), process manager
/* postlogd(8), Postfix logging
/* syslogd(8), system logging
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*
/* Wietse Venema
/* Google, Inc.
/* 111 8th Avenue
/* New York, NY 10011, USA
/*--*/
/* System library. */
#include <sys_defs.h>
#include <unistd.h>
#include <stdlib.h>
/* Utility library. */
#include <msg.h>
#include <vstream.h>
/* Global library. */
#include <deliver_request.h>
#include <mail_queue.h>
#include <bounce.h>
#include <defer.h>
#include <deliver_completed.h>
#include <flush_clnt.h>
#include <dsn_util.h>
#include <sys_exits.h>
#include <mail_proto.h>
#include <mail_version.h>
/* Single server skeleton. */
#include <mail_server.h>
/* deliver_message - deliver message with extreme prejudice */
static int deliver_message(DELIVER_REQUEST *request, const char *def_dsn,
int (*append) (int, const char *, MSG_STATS *, RECIPIENT *,
const char *, DSN *))
{
const char *myname = "deliver_message";
VSTREAM *src;
int result = 0;
int status;
RECIPIENT *rcpt;
int nrcpt;
DSN_SPLIT dp;
DSN dsn;
if (msg_verbose)
msg_info("deliver_message: from %s", request->sender);
/*
* Sanity checks.
*/
if (request->nexthop[0] == 0)
msg_fatal("empty nexthop hostname");
if (request->rcpt_list.len <= 0)
msg_fatal("recipient count: %d", request->rcpt_list.len);
/*
* Open the queue file. Opening the file can fail for a variety of
* reasons, such as the system running out of resources. Instead of
* throwing away mail, we're raising a fatal error which forces the mail
* system to back off, and retry later.
*/
src = mail_queue_open(request->queue_name, request->queue_id,
O_RDWR, 0);
if (src == 0)
msg_fatal("%s: open %s %s: %m", myname,
request->queue_name, request->queue_id);
if (msg_verbose)
msg_info("%s: file %s", myname, VSTREAM_PATH(src));
/*
* Bounce/defer/whatever all recipients.
*/
#define BOUNCE_FLAGS(request) DEL_REQ_TRACE_FLAGS(request->flags)
dsn_split(&dp, def_dsn, request->nexthop);
(void) DSN_SIMPLE(&dsn, DSN_STATUS(dp.dsn), dp.text);
for (nrcpt = 0; nrcpt < request->rcpt_list.len; nrcpt++) {
rcpt = request->rcpt_list.info + nrcpt;
status = append(BOUNCE_FLAGS(request), request->queue_id,
&request->msg_stats, rcpt, "none", &dsn);
if (status == 0)
deliver_completed(src, rcpt->offset);
result |= status;
}
/*
* Clean up.
*/
if (vstream_fclose(src))
msg_warn("close %s %s: %m", request->queue_name, request->queue_id);
return (result);
}
/* error_service - perform service for client */
static void error_service(VSTREAM *client_stream, char *service, char **argv)
{
DELIVER_REQUEST *request;
int status;
/*
* Sanity check. This service takes no command-line arguments.
*/
if (argv[0])
msg_fatal("unexpected command-line argument: %s", argv[0]);
/*
* This routine runs whenever a client connects to the UNIX-domain socket
* dedicated to the error mailer. What we see below is a little protocol
* to (1) tell the queue manager that we are ready, (2) read a request
* from the queue manager, and (3) report the completion status of that
* request. All connection-management stuff is handled by the common code
* in single_server.c.
*/
if ((request = deliver_request_read(client_stream)) != 0) {
if (strcmp(service, MAIL_SERVICE_ERROR) == 0)
status = deliver_message(request, "5.0.0", bounce_append);
else if (strcmp(service, MAIL_SERVICE_RETRY) == 0)
status = deliver_message(request, "4.0.0", defer_append);
else
msg_fatal("bad error service name: %s", service);
deliver_request_done(client_stream, request, status);
}
}
/* pre_init - pre-jail initialization */
static void pre_init(char *unused_name, char **unused_argv)
{
flush_init();
}
MAIL_VERSION_STAMP_DECLARE;
/* main - pass control to the single-threaded skeleton */
int main(int argc, char **argv)
{
/*
* Fingerprint executables and core dumps.
*/
MAIL_VERSION_STAMP_ALLOCATE;
single_server_main(argc, argv, error_service,
CA_MAIL_SERVER_PRE_INIT(pre_init),
0);
}
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