1 /* $NetBSD: error.c,v 1.2 2017/02/14 01:16:45 christos Exp $ */ 2 3 /*++ 4 /* NAME 5 /* error 8 6 /* SUMMARY 7 /* Postfix error/retry mail delivery agent 8 /* SYNOPSIS 9 /* \fBerror\fR [generic Postfix daemon options] 10 /* DESCRIPTION 11 /* The Postfix \fBerror\fR(8) delivery agent processes delivery 12 /* requests from 13 /* the queue manager. Each request specifies a queue file, a sender 14 /* address, the reason for non-delivery (specified as the 15 /* next-hop destination), and recipient information. 16 /* The reason may be prefixed with an RFC 3463-compatible detail code; 17 /* if none is specified a default 4.0.0 or 5.0.0 code is used instead. 18 /* This program expects to be run from the \fBmaster\fR(8) process 19 /* manager. 20 /* 21 /* Depending on the service name in master.cf, \fBerror\fR 22 /* or \fBretry\fR, the server bounces or defers all recipients 23 /* in the delivery request using the "next-hop" information 24 /* as the reason for non-delivery. The \fBretry\fR service name is 25 /* supported as of Postfix 2.4. 26 /* 27 /* Delivery status reports are sent to the \fBbounce\fR(8), 28 /* \fBdefer\fR(8) or \fBtrace\fR(8) daemon as appropriate. 29 /* SECURITY 30 /* .ad 31 /* .fi 32 /* The \fBerror\fR(8) mailer is not security-sensitive. It does not talk 33 /* to the network, and can be run chrooted at fixed low privilege. 34 /* STANDARDS 35 /* RFC 3463 (Enhanced Status Codes) 36 /* DIAGNOSTICS 37 /* Problems and transactions are logged to \fBsyslogd\fR(8). 38 /* 39 /* Depending on the setting of the \fBnotify_classes\fR parameter, 40 /* the postmaster is notified of bounces and of other trouble. 41 /* CONFIGURATION PARAMETERS 42 /* .ad 43 /* .fi 44 /* Changes to \fBmain.cf\fR are picked up automatically as \fBerror\fR(8) 45 /* processes run for only a limited amount of time. Use the command 46 /* "\fBpostfix reload\fR" to speed up a change. 47 /* 48 /* The text below provides only a parameter summary. See 49 /* \fBpostconf\fR(5) for more details including examples. 50 /* .IP "\fB2bounce_notice_recipient (postmaster)\fR" 51 /* The recipient of undeliverable mail that cannot be returned to 52 /* the sender. 53 /* .IP "\fBbounce_notice_recipient (postmaster)\fR" 54 /* The recipient of postmaster notifications with the message headers 55 /* of mail that Postfix did not deliver and of SMTP conversation 56 /* transcripts of mail that Postfix did not receive. 57 /* .IP "\fBconfig_directory (see 'postconf -d' output)\fR" 58 /* The default location of the Postfix main.cf and master.cf 59 /* configuration files. 60 /* .IP "\fBdaemon_timeout (18000s)\fR" 61 /* How much time a Postfix daemon process may take to handle a 62 /* request before it is terminated by a built-in watchdog timer. 63 /* .IP "\fBdelay_logging_resolution_limit (2)\fR" 64 /* The maximal number of digits after the decimal point when logging 65 /* sub-second delay values. 66 /* .IP "\fBdouble_bounce_sender (double-bounce)\fR" 67 /* The sender address of postmaster notifications that are generated 68 /* by the mail system. 69 /* .IP "\fBipc_timeout (3600s)\fR" 70 /* The time limit for sending or receiving information over an internal 71 /* communication channel. 72 /* .IP "\fBmax_idle (100s)\fR" 73 /* The maximum amount of time that an idle Postfix daemon process waits 74 /* for an incoming connection before terminating voluntarily. 75 /* .IP "\fBmax_use (100)\fR" 76 /* The maximal number of incoming connections that a Postfix daemon 77 /* process will service before terminating voluntarily. 78 /* .IP "\fBnotify_classes (resource, software)\fR" 79 /* The list of error classes that are reported to the postmaster. 80 /* .IP "\fBprocess_id (read-only)\fR" 81 /* The process ID of a Postfix command or daemon process. 82 /* .IP "\fBprocess_name (read-only)\fR" 83 /* The process name of a Postfix command or daemon process. 84 /* .IP "\fBqueue_directory (see 'postconf -d' output)\fR" 85 /* The location of the Postfix top-level queue directory. 86 /* .IP "\fBsyslog_facility (mail)\fR" 87 /* The syslog facility of Postfix logging. 88 /* .IP "\fBsyslog_name (see 'postconf -d' output)\fR" 89 /* The mail system name that is prepended to the process name in syslog 90 /* records, so that "smtpd" becomes, for example, "postfix/smtpd". 91 /* SEE ALSO 92 /* qmgr(8), queue manager 93 /* bounce(8), delivery status reports 94 /* discard(8), Postfix discard delivery agent 95 /* postconf(5), configuration parameters 96 /* master(5), generic daemon options 97 /* master(8), process manager 98 /* syslogd(8), system logging 99 /* LICENSE 100 /* .ad 101 /* .fi 102 /* The Secure Mailer license must be distributed with this software. 103 /* AUTHOR(S) 104 /* Wietse Venema 105 /* IBM T.J. Watson Research 106 /* P.O. Box 704 107 /* Yorktown Heights, NY 10598, USA 108 /* 109 /* Wietse Venema 110 /* Google, Inc. 111 /* 111 8th Avenue 112 /* New York, NY 10011, USA 113 /*--*/ 114 115 /* System library. */ 116 117 #include <sys_defs.h> 118 #include <unistd.h> 119 #include <stdlib.h> 120 121 /* Utility library. */ 122 123 #include <msg.h> 124 #include <vstream.h> 125 126 /* Global library. */ 127 128 #include <deliver_request.h> 129 #include <mail_queue.h> 130 #include <bounce.h> 131 #include <defer.h> 132 #include <deliver_completed.h> 133 #include <flush_clnt.h> 134 #include <dsn_util.h> 135 #include <sys_exits.h> 136 #include <mail_proto.h> 137 #include <mail_version.h> 138 139 /* Single server skeleton. */ 140 141 #include <mail_server.h> 142 143 /* deliver_message - deliver message with extreme prejudice */ 144 145 static int deliver_message(DELIVER_REQUEST *request, const char *def_dsn, 146 int (*append) (int, const char *, MSG_STATS *, RECIPIENT *, 147 const char *, DSN *)) 148 { 149 const char *myname = "deliver_message"; 150 VSTREAM *src; 151 int result = 0; 152 int status; 153 RECIPIENT *rcpt; 154 int nrcpt; 155 DSN_SPLIT dp; 156 DSN dsn; 157 158 if (msg_verbose) 159 msg_info("deliver_message: from %s", request->sender); 160 161 /* 162 * Sanity checks. 163 */ 164 if (request->nexthop[0] == 0) 165 msg_fatal("empty nexthop hostname"); 166 if (request->rcpt_list.len <= 0) 167 msg_fatal("recipient count: %d", request->rcpt_list.len); 168 169 /* 170 * Open the queue file. Opening the file can fail for a variety of 171 * reasons, such as the system running out of resources. Instead of 172 * throwing away mail, we're raising a fatal error which forces the mail 173 * system to back off, and retry later. 174 */ 175 src = mail_queue_open(request->queue_name, request->queue_id, 176 O_RDWR, 0); 177 if (src == 0) 178 msg_fatal("%s: open %s %s: %m", myname, 179 request->queue_name, request->queue_id); 180 if (msg_verbose) 181 msg_info("%s: file %s", myname, VSTREAM_PATH(src)); 182 183 /* 184 * Bounce/defer/whatever all recipients. 185 */ 186 #define BOUNCE_FLAGS(request) DEL_REQ_TRACE_FLAGS(request->flags) 187 188 dsn_split(&dp, def_dsn, request->nexthop); 189 (void) DSN_SIMPLE(&dsn, DSN_STATUS(dp.dsn), dp.text); 190 for (nrcpt = 0; nrcpt < request->rcpt_list.len; nrcpt++) { 191 rcpt = request->rcpt_list.info + nrcpt; 192 status = append(BOUNCE_FLAGS(request), request->queue_id, 193 &request->msg_stats, rcpt, "none", &dsn); 194 if (status == 0) 195 deliver_completed(src, rcpt->offset); 196 result |= status; 197 } 198 199 /* 200 * Clean up. 201 */ 202 if (vstream_fclose(src)) 203 msg_warn("close %s %s: %m", request->queue_name, request->queue_id); 204 205 return (result); 206 } 207 208 /* error_service - perform service for client */ 209 210 static void error_service(VSTREAM *client_stream, char *service, char **argv) 211 { 212 DELIVER_REQUEST *request; 213 int status; 214 215 /* 216 * Sanity check. This service takes no command-line arguments. 217 */ 218 if (argv[0]) 219 msg_fatal("unexpected command-line argument: %s", argv[0]); 220 221 /* 222 * This routine runs whenever a client connects to the UNIX-domain socket 223 * dedicated to the error mailer. What we see below is a little protocol 224 * to (1) tell the queue manager that we are ready, (2) read a request 225 * from the queue manager, and (3) report the completion status of that 226 * request. All connection-management stuff is handled by the common code 227 * in single_server.c. 228 */ 229 if ((request = deliver_request_read(client_stream)) != 0) { 230 if (strcmp(service, MAIL_SERVICE_ERROR) == 0) 231 status = deliver_message(request, "5.0.0", bounce_append); 232 else if (strcmp(service, MAIL_SERVICE_RETRY) == 0) 233 status = deliver_message(request, "4.0.0", defer_append); 234 else 235 msg_fatal("bad error service name: %s", service); 236 deliver_request_done(client_stream, request, status); 237 } 238 } 239 240 /* pre_init - pre-jail initialization */ 241 242 static void pre_init(char *unused_name, char **unused_argv) 243 { 244 flush_init(); 245 } 246 247 MAIL_VERSION_STAMP_DECLARE; 248 249 /* main - pass control to the single-threaded skeleton */ 250 251 int main(int argc, char **argv) 252 { 253 254 /* 255 * Fingerprint executables and core dumps. 256 */ 257 MAIL_VERSION_STAMP_ALLOCATE; 258 259 single_server_main(argc, argv, error_service, 260 CA_MAIL_SERVER_PRE_INIT(pre_init), 261 0); 262 } 263