external/ibm-public/postfix/dist/src/discard/discard.c

   1 /*      $NetBSD$        */
   2
   3 /*++
   4 /* NAME
   5 /*      discard 8
   6 /* SUMMARY
   7 /*      Postfix discard mail delivery agent
   8 /* SYNOPSIS
   9 /*      \fBdiscard\fR [generic Postfix daemon options]
  10 /* DESCRIPTION
  11 /*      The Postfix \fBdiscard\fR(8) delivery agent processes
  12 /*      delivery requests from
  13 /*      the queue manager. Each request specifies a queue file, a sender
  14 /*      address, a domain or host name that is treated as the reason for
  15 /*      discarding the mail, and recipient information.
  16 /*      The reason may be prefixed with an RFC 3463-compatible detail code.
  17 /*      This program expects to be run from the \fBmaster\fR(8) process
  18 /*      manager.
  19 /*
  20 /*      The \fBdiscard\fR(8) delivery agent pretends to deliver all recipients
  21 /*      in the delivery request, logs the "next-hop" domain or host
  22 /*      information as the reason for discarding the mail, updates the
  23 /*      queue file and marks recipients as finished or informs the
  24 /*      queue manager that delivery should be tried again at a later time.
  25 /*
  26 /*      Delivery status reports are sent to the \fBtrace\fR(8)
  27 /*      daemon as appropriate.
  28 /* SECURITY
  29 /* .ad
  30 /* .fi
  31 /*      The \fBdiscard\fR(8) mailer is not security-sensitive. It does not talk
  32 /*      to the network, and can be run chrooted at fixed low privilege.
  33 /* STANDARDS
  34 /*      None.
  35 /* DIAGNOSTICS
  36 /*      Problems and transactions are logged to \fBsyslogd\fR(8).
  37 /*
  38 /*      Depending on the setting of the \fBnotify_classes\fR parameter,
  39 /*      the postmaster is notified of bounces and of other trouble.
  40 /* CONFIGURATION PARAMETERS
  41 /* .ad
  42 /* .fi
  43 /*      Changes to \fBmain.cf\fR are picked up automatically as \fBdiscard\fR(8)
  44 /*      processes run for only a limited amount of time. Use the command
  45 /*      "\fBpostfix reload\fR" to speed up a change.
  46 /*
  47 /*      The text below provides only a parameter summary. See
  48 /*      \fBpostconf\fR(5) for more details including examples.
  49 /* .IP "\fBconfig_directory (see 'postconf -d' output)\fR"
  50 /*      The default location of the Postfix main.cf and master.cf
  51 /*      configuration files.
  52 /* .IP "\fBdaemon_timeout (18000s)\fR"
  53 /*      How much time a Postfix daemon process may take to handle a
  54 /*      request before it is terminated by a built-in watchdog timer.
  55 /* .IP "\fBdelay_logging_resolution_limit (2)\fR"
  56 /*      The maximal number of digits after the decimal point when logging
  57 /*      sub-second delay values.
  58 /* .IP "\fBdouble_bounce_sender (double-bounce)\fR"
  59 /*      The sender address of postmaster notifications that are generated
  60 /*      by the mail system.
  61 /* .IP "\fBipc_timeout (3600s)\fR"
  62 /*      The time limit for sending or receiving information over an internal
  63 /*      communication channel.
  64 /* .IP "\fBmax_idle (100s)\fR"
  65 /*      The maximum amount of time that an idle Postfix daemon process waits
  66 /*      for an incoming connection before terminating voluntarily.
  67 /* .IP "\fBmax_use (100)\fR"
  68 /*      The maximal number of incoming connections that a Postfix daemon
  69 /*      process will service before terminating voluntarily.
  70 /* .IP "\fBprocess_id (read-only)\fR"
  71 /*      The process ID of a Postfix command or daemon process.
  72 /* .IP "\fBprocess_name (read-only)\fR"
  73 /*      The process name of a Postfix command or daemon process.
  74 /* .IP "\fBqueue_directory (see 'postconf -d' output)\fR"
  75 /*      The location of the Postfix top-level queue directory.
  76 /* .IP "\fBsyslog_facility (mail)\fR"
  77 /*      The syslog facility of Postfix logging.
  78 /* .IP "\fBsyslog_name (see 'postconf -d' output)\fR"
  79 /*      The mail system name that is prepended to the process name in syslog
  80 /*      records, so that "smtpd" becomes, for example, "postfix/smtpd".
  81 /* SEE ALSO
  82 /*      qmgr(8), queue manager
  83 /*      bounce(8), delivery status reports
  84 /*      error(8), Postfix error delivery agent
  85 /*      postconf(5), configuration parameters
  86 /*      master(5), generic daemon options
  87 /*      master(8), process manager
  88 /*      syslogd(8), system logging
  89 /* LICENSE
  90 /* .ad
  91 /* .fi
  92 /*      The Secure Mailer license must be distributed with this software.
  93 /* HISTORY
  94 /*      This service was introduced with Postfix version 2.2.
  95 /* AUTHOR(S)
  96 /*      Victor Duchovni
  97 /*      Morgan Stanley
  98 /*
  99 /*      Based on code by:
 100 /*      Wietse Venema
 101 /*      IBM T.J. Watson Research
 102 /*      P.O. Box 704
 103 /*      Yorktown Heights, NY 10598, USA
 104 /*--*/
 105
 106 /* System library. */
 107
 108 #include <sys_defs.h>
 109 #include <unistd.h>
 110 #include <stdlib.h>
 111
 112 /* Utility library. */
 113
 114 #include <msg.h>
 115 #include <vstream.h>
 116
 117 /* Global library. */
 118
 119 #include <deliver_request.h>
 120 #include <mail_queue.h>
 121 #include <bounce.h>
 122 #include <deliver_completed.h>
 123 #include <flush_clnt.h>
 124 #include <sent.h>
 125 #include <dsn_util.h>
 126 #include <mail_version.h>
 127
 128 /* Single server skeleton. */
 129
 130 #include <mail_server.h>
 131
 132 /* deliver_message - deliver message with extreme prejudice */
 133
 134 static int deliver_message(DELIVER_REQUEST *request)
 135 {
 136     const char *myname = "deliver_message";
 137     VSTREAM *src;
 138     int     result = 0;
 139     int     status;
 140     RECIPIENT *rcpt;
 141     int     nrcpt;
 142     DSN_SPLIT dp;
 143     DSN     dsn;
 144
 145     if (msg_verbose)
 146         msg_info("deliver_message: from %s", request->sender);
 147
 148     /*
 149      * Sanity checks.
 150      */
 151     if (request->nexthop[0] == 0)
 152         msg_fatal("empty nexthop hostname");
 153     if (request->rcpt_list.len <= 0)
 154         msg_fatal("recipient count: %d", request->rcpt_list.len);
 155
 156     /*
 157      * Open the queue file. Opening the file can fail for a variety of
 158      * reasons, such as the system running out of resources. Instead of
 159      * throwing away mail, we're raising a fatal error which forces the mail
 160      * system to back off, and retry later.
 161      */
 162     src = mail_queue_open(request->queue_name, request->queue_id,
 163                           O_RDWR, 0);
 164     if (src == 0)
 165         msg_fatal("%s: open %s %s: %m", myname,
 166                   request->queue_name, request->queue_id);
 167     if (msg_verbose)
 168         msg_info("%s: file %s", myname, VSTREAM_PATH(src));
 169
 170     /*
 171      * Discard all recipients.
 172      */
 173 #define BOUNCE_FLAGS(request) DEL_REQ_TRACE_FLAGS(request->flags)
 174
 175     dsn_split(&dp, "2.0.0", request->nexthop);
 176     (void) DSN_SIMPLE(&dsn, DSN_STATUS(dp.dsn), dp.text);
 177     for (nrcpt = 0; nrcpt < request->rcpt_list.len; nrcpt++) {
 178         rcpt = request->rcpt_list.info + nrcpt;
 179         status = sent(BOUNCE_FLAGS(request), request->queue_id,
 180                       &request->msg_stats, rcpt, "none", &dsn);
 181         if (status == 0 && (request->flags & DEL_REQ_FLAG_SUCCESS))
 182             deliver_completed(src, rcpt->offset);
 183         result |= status;
 184     }
 185
 186     /*
 187      * Clean up.
 188      */
 189     if (vstream_fclose(src))
 190         msg_warn("close %s %s: %m", request->queue_name, request->queue_id);
 191
 192     return (result);
 193 }
 194
 195 /* discard_service - perform service for client */
 196
 197 static void discard_service(VSTREAM *client_stream, char *unused_service, char **argv)
 198 {
 199     DELIVER_REQUEST *request;
 200     int     status;
 201
 202     /*
 203      * Sanity check. This service takes no command-line arguments.
 204      */
 205     if (argv[0])
 206         msg_fatal("unexpected command-line argument: %s", argv[0]);
 207
 208     /*
 209      * This routine runs whenever a client connects to the UNIX-domain socket
 210      * dedicated to the discard mailer. What we see below is a little
 211      * protocol to (1) tell the queue manager that we are ready, (2) read a
 212      * request from the queue manager, and (3) report the completion status
 213      * of that request. All connection-management stuff is handled by the
 214      * common code in single_server.c.
 215      */
 216     if ((request = deliver_request_read(client_stream)) != 0) {
 217         status = deliver_message(request);
 218         deliver_request_done(client_stream, request, status);
 219     }
 220 }
 221
 222 /* pre_init - pre-jail initialization */
 223
 224 static void pre_init(char *unused_name, char **unused_argv)
 225 {
 226     flush_init();
 227 }
 228
 229 MAIL_VERSION_STAMP_DECLARE;
 230
 231 /* main - pass control to the single-threaded skeleton */
 232
 233 int     main(int argc, char **argv)
 234 {
 235
 236     /*
 237      * Fingerprint executables and core dumps.
 238      */
 239     MAIL_VERSION_STAMP_ALLOCATE;
 240
 241     single_server_main(argc, argv, discard_service,
 242                        MAIL_SERVER_PRE_INIT, pre_init,
 243                        0);
 244 }