1 /* $NetBSD: qmgr_deliver.c,v 1.3 2022/10/08 16:12:48 christos Exp $ */ 2 3 /*++ 4 /* NAME 5 /* qmgr_deliver 3 6 /* SUMMARY 7 /* deliver one per-site queue entry to that site 8 /* SYNOPSIS 9 /* #include "qmgr.h" 10 /* 11 /* int qmgr_deliver_concurrency; 12 /* 13 /* int qmgr_deliver(transport, fp) 14 /* QMGR_TRANSPORT *transport; 15 /* VSTREAM *fp; 16 /* DESCRIPTION 17 /* This module implements the client side of the `queue manager 18 /* to delivery agent' protocol. The queue manager uses 19 /* asynchronous I/O so that it can drive multiple delivery 20 /* agents in parallel. Depending on the outcome of a delivery 21 /* attempt, the status of messages, queues and transports is 22 /* updated. 23 /* 24 /* qmgr_deliver_concurrency is a global counter that says how 25 /* many delivery processes are in use. This can be used, for 26 /* example, to control the size of the `active' message queue. 27 /* 28 /* qmgr_deliver() executes when a delivery process announces its 29 /* availability for the named transport. It arranges for delivery 30 /* of a suitable queue entry. The \fIfp\fR argument specifies a 31 /* stream that is connected to a delivery process, or a null 32 /* pointer if the transport accepts no connection. Upon completion 33 /* of delivery (successful or not), the stream is closed, so that the 34 /* delivery process is released. 35 /* DIAGNOSTICS 36 /* LICENSE 37 /* .ad 38 /* .fi 39 /* The Secure Mailer license must be distributed with this software. 40 /* AUTHOR(S) 41 /* Wietse Venema 42 /* IBM T.J. Watson Research 43 /* P.O. Box 704 44 /* Yorktown Heights, NY 10598, USA 45 /* 46 /* Preemptive scheduler enhancements: 47 /* Patrik Rak 48 /* Modra 6 49 /* 155 00, Prague, Czech Republic 50 /* 51 /* Wietse Venema 52 /* Google, Inc. 53 /* 111 8th Avenue 54 /* New York, NY 10011, USA 55 /*--*/ 56 57 /* System library. */ 58 59 #include <sys_defs.h> 60 #include <time.h> 61 #include <string.h> 62 63 /* Utility library. */ 64 65 #include <msg.h> 66 #include <vstring.h> 67 #include <vstream.h> 68 #include <vstring_vstream.h> 69 #include <events.h> 70 #include <iostuff.h> 71 #include <stringops.h> 72 #include <mymalloc.h> 73 74 /* Global library. */ 75 76 #include <mail_queue.h> 77 #include <mail_proto.h> 78 #include <recipient_list.h> 79 #include <mail_params.h> 80 #include <deliver_request.h> 81 #include <verp_sender.h> 82 #include <dsn_util.h> 83 #include <dsn_buf.h> 84 #include <dsb_scan.h> 85 #include <rcpt_print.h> 86 #include <smtputf8.h> 87 88 /* Application-specific. */ 89 90 #include "qmgr.h" 91 92 /* 93 * Important note on the _transport_rate_delay implementation: after 94 * qmgr_transport_alloc() sets the QMGR_TRANSPORT_STAT_RATE_LOCK flag, all 95 * code paths must directly or indirectly invoke qmgr_transport_unthrottle() 96 * or qmgr_transport_throttle(). Otherwise, transports with non-zero 97 * _transport_rate_delay will become stuck. 98 */ 99 100 int qmgr_deliver_concurrency; 101 102 /* 103 * Message delivery status codes. 104 */ 105 #define DELIVER_STAT_OK 0 /* all recipients delivered */ 106 #define DELIVER_STAT_DEFER 1 /* try some recipients later */ 107 #define DELIVER_STAT_CRASH 2 /* mailer internal problem */ 108 109 /* qmgr_deliver_initial_reply - retrieve initial delivery process response */ 110 111 static int qmgr_deliver_initial_reply(VSTREAM *stream) 112 { 113 if (peekfd(vstream_fileno(stream)) < 0) { 114 msg_warn("%s: premature disconnect", VSTREAM_PATH(stream)); 115 return (DELIVER_STAT_CRASH); 116 } else if (attr_scan(stream, ATTR_FLAG_STRICT, 117 RECV_ATTR_STREQ(MAIL_ATTR_PROTO, MAIL_ATTR_PROTO_DELIVER), 118 ATTR_TYPE_END) != 0) { 119 msg_warn("%s: malformed response", VSTREAM_PATH(stream)); 120 return (DELIVER_STAT_DEFER); 121 } else { 122 return (0); 123 } 124 } 125 126 /* qmgr_deliver_final_reply - retrieve final delivery process response */ 127 128 static int qmgr_deliver_final_reply(VSTREAM *stream, DSN_BUF *dsb) 129 { 130 int stat; 131 132 if (peekfd(vstream_fileno(stream)) < 0) { 133 msg_warn("%s: premature disconnect", VSTREAM_PATH(stream)); 134 return (DELIVER_STAT_CRASH); 135 } else if (attr_scan(stream, ATTR_FLAG_STRICT, 136 RECV_ATTR_FUNC(dsb_scan, (void *) dsb), 137 RECV_ATTR_INT(MAIL_ATTR_STATUS, &stat), 138 ATTR_TYPE_END) != 2) { 139 msg_warn("%s: malformed response", VSTREAM_PATH(stream)); 140 return (DELIVER_STAT_CRASH); 141 } else { 142 return (stat ? DELIVER_STAT_DEFER : 0); 143 } 144 } 145 146 /* qmgr_deliver_send_request - send delivery request to delivery process */ 147 148 static int qmgr_deliver_send_request(QMGR_ENTRY *entry, VSTREAM *stream) 149 { 150 RECIPIENT_LIST list = entry->rcpt_list; 151 RECIPIENT *recipient; 152 QMGR_MESSAGE *message = entry->message; 153 VSTRING *sender_buf = 0; 154 MSG_STATS stats; 155 char *sender; 156 int flags; 157 int smtputf8 = message->smtputf8; 158 const char *addr; 159 160 /* 161 * Todo: integrate with code up-stream that builds the delivery request. 162 */ 163 for (recipient = list.info; recipient < list.info + list.len; recipient++) 164 if (var_smtputf8_enable && (addr = recipient->address)[0] 165 && !allascii(addr) && valid_utf8_string(addr, strlen(addr))) { 166 smtputf8 |= SMTPUTF8_FLAG_RECIPIENT; 167 if (message->verp_delims) 168 smtputf8 |= SMTPUTF8_FLAG_SENDER; 169 } 170 171 /* 172 * If variable envelope return path is requested, change prefix+@origin 173 * into prefix+user=domain@origin. Note that with VERP there is only one 174 * recipient per delivery. 175 */ 176 if (message->verp_delims == 0) { 177 sender = message->sender; 178 } else { 179 sender_buf = vstring_alloc(100); 180 verp_sender(sender_buf, message->verp_delims, 181 message->sender, list.info); 182 sender = vstring_str(sender_buf); 183 } 184 185 flags = message->tflags 186 | entry->queue->dflags 187 | (message->inspect_xport ? DEL_REQ_FLAG_BOUNCE : DEL_REQ_FLAG_DEFLT); 188 (void) QMGR_MSG_STATS(&stats, message); 189 attr_print(stream, ATTR_FLAG_NONE, 190 SEND_ATTR_INT(MAIL_ATTR_FLAGS, flags), 191 SEND_ATTR_STR(MAIL_ATTR_QUEUE, message->queue_name), 192 SEND_ATTR_STR(MAIL_ATTR_QUEUEID, message->queue_id), 193 SEND_ATTR_LONG(MAIL_ATTR_OFFSET, message->data_offset), 194 SEND_ATTR_LONG(MAIL_ATTR_SIZE, message->cont_length), 195 SEND_ATTR_STR(MAIL_ATTR_NEXTHOP, entry->queue->nexthop), 196 SEND_ATTR_STR(MAIL_ATTR_ENCODING, message->encoding), 197 SEND_ATTR_INT(MAIL_ATTR_SMTPUTF8, smtputf8), 198 SEND_ATTR_STR(MAIL_ATTR_SENDER, sender), 199 SEND_ATTR_STR(MAIL_ATTR_DSN_ENVID, message->dsn_envid), 200 SEND_ATTR_INT(MAIL_ATTR_DSN_RET, message->dsn_ret), 201 SEND_ATTR_FUNC(msg_stats_print, (const void *) &stats), 202 /* XXX Should be encapsulated with ATTR_TYPE_FUNC. */ 203 SEND_ATTR_STR(MAIL_ATTR_LOG_CLIENT_NAME, message->client_name), 204 SEND_ATTR_STR(MAIL_ATTR_LOG_CLIENT_ADDR, message->client_addr), 205 SEND_ATTR_STR(MAIL_ATTR_LOG_CLIENT_PORT, message->client_port), 206 SEND_ATTR_STR(MAIL_ATTR_LOG_PROTO_NAME, message->client_proto), 207 SEND_ATTR_STR(MAIL_ATTR_LOG_HELO_NAME, message->client_helo), 208 /* XXX Should be encapsulated with ATTR_TYPE_FUNC. */ 209 SEND_ATTR_STR(MAIL_ATTR_SASL_METHOD, message->sasl_method), 210 SEND_ATTR_STR(MAIL_ATTR_SASL_USERNAME, message->sasl_username), 211 SEND_ATTR_STR(MAIL_ATTR_SASL_SENDER, message->sasl_sender), 212 /* XXX Ditto if we want to pass TLS certificate info. */ 213 SEND_ATTR_STR(MAIL_ATTR_LOG_IDENT, message->log_ident), 214 SEND_ATTR_STR(MAIL_ATTR_RWR_CONTEXT, message->rewrite_context), 215 SEND_ATTR_INT(MAIL_ATTR_RCPT_COUNT, list.len), 216 ATTR_TYPE_END); 217 if (sender_buf != 0) 218 vstring_free(sender_buf); 219 for (recipient = list.info; recipient < list.info + list.len; recipient++) 220 attr_print(stream, ATTR_FLAG_NONE, 221 SEND_ATTR_FUNC(rcpt_print, (const void *) recipient), 222 ATTR_TYPE_END); 223 if (vstream_fflush(stream) != 0) { 224 msg_warn("write to process (%s): %m", entry->queue->transport->name); 225 return (-1); 226 } else { 227 if (msg_verbose) 228 msg_info("qmgr_deliver: site `%s'", entry->queue->name); 229 return (0); 230 } 231 } 232 233 /* qmgr_deliver_abort - transport response watchdog */ 234 235 static void qmgr_deliver_abort(int unused_event, void *context) 236 { 237 QMGR_ENTRY *entry = (QMGR_ENTRY *) context; 238 QMGR_QUEUE *queue = entry->queue; 239 QMGR_TRANSPORT *transport = queue->transport; 240 QMGR_MESSAGE *message = entry->message; 241 242 msg_fatal("%s: timeout receiving delivery status from transport: %s", 243 message->queue_id, transport->name); 244 } 245 246 /* qmgr_deliver_update - process delivery status report */ 247 248 static void qmgr_deliver_update(int unused_event, void *context) 249 { 250 QMGR_ENTRY *entry = (QMGR_ENTRY *) context; 251 QMGR_QUEUE *queue = entry->queue; 252 QMGR_TRANSPORT *transport = queue->transport; 253 QMGR_MESSAGE *message = entry->message; 254 static DSN_BUF *dsb; 255 int status; 256 257 /* 258 * Release the delivery agent from a "hot" queue entry. 259 */ 260 #define QMGR_DELIVER_RELEASE_AGENT(entry) do { \ 261 event_disable_readwrite(vstream_fileno(entry->stream)); \ 262 (void) vstream_fclose(entry->stream); \ 263 entry->stream = 0; \ 264 qmgr_deliver_concurrency--; \ 265 } while (0) 266 267 if (dsb == 0) 268 dsb = dsb_create(); 269 270 /* 271 * The message transport has responded. Stop the watchdog timer. 272 */ 273 event_cancel_timer(qmgr_deliver_abort, context); 274 275 /* 276 * Retrieve the delivery agent status report. The numerical status code 277 * indicates if delivery should be tried again. The reason text is sent 278 * only when a site should be avoided for a while, so that the queue 279 * manager can log why it does not even try to schedule delivery to the 280 * affected recipients. 281 */ 282 status = qmgr_deliver_final_reply(entry->stream, dsb); 283 284 /* 285 * The mail delivery process failed for some reason (although delivery 286 * may have been successful). Back off with this transport type for a 287 * while. Dispose of queue entries for this transport that await 288 * selection (the todo lists). Stay away from queue entries that have 289 * been selected (the busy lists), or we would have dangling pointers. 290 * The queue itself won't go away before we dispose of the current queue 291 * entry. 292 */ 293 if (status == DELIVER_STAT_CRASH) { 294 message->flags |= DELIVER_STAT_DEFER; 295 #if 0 296 whatsup = concatenate("unknown ", transport->name, 297 " mail transport error", (char *) 0); 298 qmgr_transport_throttle(transport, 299 DSN_SIMPLE(&dsb->dsn, "4.3.0", whatsup)); 300 myfree(whatsup); 301 #else 302 qmgr_transport_throttle(transport, 303 DSN_SIMPLE(&dsb->dsn, "4.3.0", 304 "unknown mail transport error")); 305 #endif 306 msg_warn("transport %s failure -- see a previous warning/fatal/panic logfile record for the problem description", 307 transport->name); 308 309 /* 310 * Assume the worst and write a defer logfile record for each 311 * recipient. This omission was already present in the first queue 312 * manager implementation of 199703, and was fixed 200511. 313 * 314 * To avoid the synchronous qmgr_defer_recipient() operation for each 315 * recipient of this queue entry, release the delivery process and 316 * move the entry back to the todo queue. Let qmgr_defer_transport() 317 * log the recipient asynchronously if possible, and get out of here. 318 * Note: if asynchronous logging is not possible, 319 * qmgr_defer_transport() eventually invokes qmgr_entry_done() and 320 * the entry becomes a dangling pointer. 321 */ 322 QMGR_DELIVER_RELEASE_AGENT(entry); 323 qmgr_entry_unselect(entry); 324 qmgr_defer_transport(transport, &dsb->dsn); 325 return; 326 } 327 328 /* 329 * This message must be tried again. 330 * 331 * If we have a problem talking to this site, back off with this site for a 332 * while; dispose of queue entries for this site that await selection 333 * (the todo list); stay away from queue entries that have been selected 334 * (the busy list), or we would have dangling pointers. The queue itself 335 * won't go away before we dispose of the current queue entry. 336 * 337 * XXX Caution: DSN_COPY() will panic on empty status or reason. 338 */ 339 #define SUSPENDED "delivery temporarily suspended: " 340 341 if (status == DELIVER_STAT_DEFER) { 342 message->flags |= DELIVER_STAT_DEFER; 343 if (VSTRING_LEN(dsb->status)) { 344 /* Sanitize the DSN status/reason from the delivery agent. */ 345 if (!dsn_valid(vstring_str(dsb->status))) 346 vstring_strcpy(dsb->status, "4.0.0"); 347 if (VSTRING_LEN(dsb->reason) == 0) 348 vstring_strcpy(dsb->reason, "unknown error"); 349 vstring_prepend(dsb->reason, SUSPENDED, sizeof(SUSPENDED) - 1); 350 if (QMGR_QUEUE_READY(queue)) { 351 qmgr_queue_throttle(queue, DSN_FROM_DSN_BUF(dsb)); 352 if (QMGR_QUEUE_THROTTLED(queue)) 353 qmgr_defer_todo(queue, &dsb->dsn); 354 } 355 } 356 } 357 358 /* 359 * No problems detected. Mark the transport and queue as alive. The queue 360 * itself won't go away before we dispose of the current queue entry. 361 */ 362 if (status != DELIVER_STAT_CRASH) { 363 qmgr_transport_unthrottle(transport); 364 if (VSTRING_LEN(dsb->reason) == 0) 365 qmgr_queue_unthrottle(queue); 366 } 367 368 /* 369 * Release the delivery process, and give some other queue entry a chance 370 * to be delivered. When all recipients for a message have been tried, 371 * decide what to do next with this message: defer, bounce, delete. 372 */ 373 QMGR_DELIVER_RELEASE_AGENT(entry); 374 qmgr_entry_done(entry, QMGR_QUEUE_BUSY); 375 } 376 377 /* qmgr_deliver - deliver one per-site queue entry */ 378 379 void qmgr_deliver(QMGR_TRANSPORT *transport, VSTREAM *stream) 380 { 381 QMGR_ENTRY *entry; 382 DSN dsn; 383 384 /* 385 * Find out if this delivery process is really available. Once elected, 386 * the delivery process is supposed to express its happiness. If there is 387 * a problem, wipe the pending deliveries for this transport. This 388 * routine runs in response to an external event, so it does not run 389 * while some other queue manipulation is happening. 390 */ 391 if (stream == 0 || qmgr_deliver_initial_reply(stream) != 0) { 392 #if 0 393 whatsup = concatenate(transport->name, 394 " mail transport unavailable", (char *) 0); 395 qmgr_transport_throttle(transport, 396 DSN_SIMPLE(&dsn, "4.3.0", whatsup)); 397 myfree(whatsup); 398 #else 399 qmgr_transport_throttle(transport, 400 DSN_SIMPLE(&dsn, "4.3.0", 401 "mail transport unavailable")); 402 #endif 403 qmgr_defer_transport(transport, &dsn); 404 if (stream) 405 (void) vstream_fclose(stream); 406 return; 407 } 408 409 /* 410 * Find a suitable queue entry. Things may have changed since this 411 * transport was allocated. If no suitable entry is found, 412 * unceremoniously disconnect from the delivery process. The delivery 413 * agent request reading routine is prepared for the queue manager to 414 * change its mind for no apparent reason. 415 */ 416 if ((entry = qmgr_job_entry_select(transport)) == 0) { 417 (void) vstream_fclose(stream); 418 return; 419 } 420 421 /* 422 * Send the queue file info and recipient info to the delivery process. 423 * If there is a problem, wipe the pending deliveries for this transport. 424 * This routine runs in response to an external event, so it does not run 425 * while some other queue manipulation is happening. 426 */ 427 if (qmgr_deliver_send_request(entry, stream) < 0) { 428 qmgr_entry_unselect(entry); 429 #if 0 430 whatsup = concatenate(transport->name, 431 " mail transport unavailable", (char *) 0); 432 qmgr_transport_throttle(transport, 433 DSN_SIMPLE(&dsn, "4.3.0", whatsup)); 434 myfree(whatsup); 435 #else 436 qmgr_transport_throttle(transport, 437 DSN_SIMPLE(&dsn, "4.3.0", 438 "mail transport unavailable")); 439 #endif 440 qmgr_defer_transport(transport, &dsn); 441 /* warning: entry may be a dangling pointer here */ 442 (void) vstream_fclose(stream); 443 return; 444 } 445 446 /* 447 * If we get this far, go wait for the delivery status report. 448 */ 449 qmgr_deliver_concurrency++; 450 entry->stream = stream; 451 event_enable_read(vstream_fileno(stream), 452 qmgr_deliver_update, (void *) entry); 453 454 /* 455 * Guard against broken systems. 456 */ 457 event_request_timer(qmgr_deliver_abort, (void *) entry, var_daemon_timeout); 458 } 459