1/* $NetBSD$ */ 2 3/*++ 4/* NAME 5/* deliver_request 3 6/* SUMMARY 7/* mail delivery request protocol, server side 8/* SYNOPSIS 9/* #include <deliver_request.h> 10/* 11/* typedef struct DELIVER_REQUEST { 12/* .in +5 13/* VSTREAM *fp; 14/* int flags; 15/* char *queue_name; 16/* char *queue_id; 17/* long data_offset; 18/* long data_size; 19/* char *nexthop; 20/* char *encoding; 21/* char *sender; 22/* MSG_STATS msg_stats; 23/* RECIPIENT_LIST rcpt_list; 24/* DSN *hop_status; 25/* char *client_name; 26/* char *client_addr; 27/* char *client_port; 28/* char *client_proto; 29/* char *client_helo; 30/* char *sasl_method; 31/* char *sasl_username; 32/* char *sasl_sender; 33/* char *log_ident; 34/* char *rewrite_context; 35/* char *dsn_envid; 36/* int dsn_ret; 37/* .in -5 38/* } DELIVER_REQUEST; 39/* 40/* DELIVER_REQUEST *deliver_request_read(stream) 41/* VSTREAM *stream; 42/* 43/* void deliver_request_done(stream, request, status) 44/* VSTREAM *stream; 45/* DELIVER_REQUEST *request; 46/* int status; 47/* DESCRIPTION 48/* This module implements the delivery agent side of the `queue manager 49/* to delivery agent' protocol. In this game, the queue manager is 50/* the client, while the delivery agent is the server. 51/* 52/* deliver_request_read() reads a client message delivery request, 53/* opens the queue file, and acquires a shared lock. 54/* A null result means that the client sent bad information or that 55/* it went away unexpectedly. 56/* 57/* The \fBflags\fR structure member is the bit-wise OR of zero or more 58/* of the following: 59/* .IP \fBDEL_REQ_FLAG_SUCCESS\fR 60/* Delete successful recipients from the queue file. 61/* 62/* Note: currently, this also controls whether bounced recipients 63/* are deleted. 64/* 65/* Note: the deliver_completed() function ignores this request 66/* when the recipient queue file offset is -1. 67/* .IP \fBDEL_REQ_FLAG_BOUNCE\fR 68/* Delete bounced recipients from the queue file. Currently, 69/* this flag is non-functional. 70/* .PP 71/* The \fBDEL_REQ_FLAG_DEFLT\fR constant provides a convenient shorthand 72/* for the most common case: delete successful and bounced recipients. 73/* 74/* The \fIhop_status\fR member must be updated by the caller 75/* when all delivery to the destination in \fInexthop\fR should 76/* be deferred. This member is passed to to dsn_free(). 77/* 78/* deliver_request_done() reports the delivery status back to the 79/* client, including the optional \fIhop_status\fR etc. information, 80/* closes the queue file, 81/* and destroys the DELIVER_REQUEST structure. The result is 82/* non-zero when the status could not be reported to the client. 83/* DIAGNOSTICS 84/* Warnings: bad data sent by the client. Fatal errors: out of 85/* memory, queue file open errors. 86/* SEE ALSO 87/* attr_scan(3) low-level intra-mail input routines 88/* LICENSE 89/* .ad 90/* .fi 91/* The Secure Mailer license must be distributed with this software. 92/* AUTHOR(S) 93/* Wietse Venema 94/* IBM T.J. Watson Research 95/* P.O. Box 704 96/* Yorktown Heights, NY 10598, USA 97/*--*/ 98 99/* System library. */ 100 101#include <sys_defs.h> 102#include <sys/stat.h> 103#include <string.h> 104#include <unistd.h> 105#include <errno.h> 106 107/* Utility library. */ 108 109#include <msg.h> 110#include <vstream.h> 111#include <vstring.h> 112#include <mymalloc.h> 113#include <iostuff.h> 114#include <myflock.h> 115 116/* Global library. */ 117 118#include "mail_queue.h" 119#include "mail_proto.h" 120#include "mail_open_ok.h" 121#include "recipient_list.h" 122#include "dsn.h" 123#include "dsn_print.h" 124#include "deliver_request.h" 125#include "rcpt_buf.h" 126 127/* deliver_request_initial - send initial status code */ 128 129static int deliver_request_initial(VSTREAM *stream) 130{ 131 int err; 132 133 /* 134 * The master processes runs a finite number of delivery agent processes 135 * to handle service requests. Thus, a delivery agent process must send 136 * something to inform the queue manager that it is ready to receive a 137 * delivery request; otherwise the queue manager could block in write(). 138 */ 139 if (msg_verbose) 140 msg_info("deliver_request_initial: send initial status"); 141 attr_print(stream, ATTR_FLAG_NONE, 142 ATTR_TYPE_INT, MAIL_ATTR_STATUS, 0, 143 ATTR_TYPE_END); 144 if ((err = vstream_fflush(stream)) != 0) 145 if (msg_verbose) 146 msg_warn("send initial status: %m"); 147 return (err); 148} 149 150/* deliver_request_final - send final delivery request status */ 151 152static int deliver_request_final(VSTREAM *stream, DELIVER_REQUEST *request, 153 int status) 154{ 155 DSN *hop_status; 156 int err; 157 158 /* XXX This DSN structure initialization bypasses integrity checks. */ 159 static DSN dummy_dsn = {"", "", "", "", "", "", ""}; 160 161 /* 162 * Send the status and the optional reason. 163 */ 164 if ((hop_status = request->hop_status) == 0) 165 hop_status = &dummy_dsn; 166 if (msg_verbose) 167 msg_info("deliver_request_final: send: \"%s\" %d", 168 hop_status->reason, status); 169 attr_print(stream, ATTR_FLAG_NONE, 170 ATTR_TYPE_FUNC, dsn_print, (void *) hop_status, 171 ATTR_TYPE_INT, MAIL_ATTR_STATUS, status, 172 ATTR_TYPE_END); 173 if ((err = vstream_fflush(stream)) != 0) 174 if (msg_verbose) 175 msg_warn("send final status: %m"); 176 177 /* 178 * With some UNIX systems, stream sockets lose data when you close them 179 * immediately after writing to them. That is not how sockets are 180 * supposed to behave! The workaround is to wait until the receiver 181 * closes the connection. Calling VSTREAM_GETC() has the benefit of using 182 * whatever timeout is specified in the ipc_timeout parameter. 183 */ 184 (void) VSTREAM_GETC(stream); 185 return (err); 186} 187 188/* deliver_request_get - receive message delivery request */ 189 190static int deliver_request_get(VSTREAM *stream, DELIVER_REQUEST *request) 191{ 192 const char *myname = "deliver_request_get"; 193 const char *path; 194 struct stat st; 195 static VSTRING *queue_name; 196 static VSTRING *queue_id; 197 static VSTRING *nexthop; 198 static VSTRING *encoding; 199 static VSTRING *address; 200 static VSTRING *client_name; 201 static VSTRING *client_addr; 202 static VSTRING *client_port; 203 static VSTRING *client_proto; 204 static VSTRING *client_helo; 205 static VSTRING *sasl_method; 206 static VSTRING *sasl_username; 207 static VSTRING *sasl_sender; 208 static VSTRING *log_ident; 209 static VSTRING *rewrite_context; 210 static VSTRING *dsn_envid; 211 static RCPT_BUF *rcpt_buf; 212 int rcpt_count; 213 int dsn_ret; 214 215 /* 216 * Initialize. For some reason I wanted to allow for multiple instances 217 * of a deliver_request structure, thus the hoopla with string 218 * initialization and copying. 219 */ 220 if (queue_name == 0) { 221 queue_name = vstring_alloc(10); 222 queue_id = vstring_alloc(10); 223 nexthop = vstring_alloc(10); 224 encoding = vstring_alloc(10); 225 address = vstring_alloc(10); 226 client_name = vstring_alloc(10); 227 client_addr = vstring_alloc(10); 228 client_port = vstring_alloc(10); 229 client_proto = vstring_alloc(10); 230 client_helo = vstring_alloc(10); 231 sasl_method = vstring_alloc(10); 232 sasl_username = vstring_alloc(10); 233 sasl_sender = vstring_alloc(10); 234 log_ident = vstring_alloc(10); 235 rewrite_context = vstring_alloc(10); 236 dsn_envid = vstring_alloc(10); 237 rcpt_buf = rcpb_create(); 238 } 239 240 /* 241 * Extract the queue file name, data offset, and sender address. Abort 242 * the conversation when they send bad information. 243 */ 244 if (attr_scan(stream, ATTR_FLAG_STRICT, 245 ATTR_TYPE_INT, MAIL_ATTR_FLAGS, &request->flags, 246 ATTR_TYPE_STR, MAIL_ATTR_QUEUE, queue_name, 247 ATTR_TYPE_STR, MAIL_ATTR_QUEUEID, queue_id, 248 ATTR_TYPE_LONG, MAIL_ATTR_OFFSET, &request->data_offset, 249 ATTR_TYPE_LONG, MAIL_ATTR_SIZE, &request->data_size, 250 ATTR_TYPE_STR, MAIL_ATTR_NEXTHOP, nexthop, 251 ATTR_TYPE_STR, MAIL_ATTR_ENCODING, encoding, 252 ATTR_TYPE_STR, MAIL_ATTR_SENDER, address, 253 ATTR_TYPE_STR, MAIL_ATTR_DSN_ENVID, dsn_envid, 254 ATTR_TYPE_INT, MAIL_ATTR_DSN_RET, &dsn_ret, 255 ATTR_TYPE_FUNC, msg_stats_scan, (void *) &request->msg_stats, 256 /* XXX Should be encapsulated with ATTR_TYPE_FUNC. */ 257 ATTR_TYPE_STR, MAIL_ATTR_LOG_CLIENT_NAME, client_name, 258 ATTR_TYPE_STR, MAIL_ATTR_LOG_CLIENT_ADDR, client_addr, 259 ATTR_TYPE_STR, MAIL_ATTR_LOG_CLIENT_PORT, client_port, 260 ATTR_TYPE_STR, MAIL_ATTR_LOG_PROTO_NAME, client_proto, 261 ATTR_TYPE_STR, MAIL_ATTR_LOG_HELO_NAME, client_helo, 262 /* XXX Should be encapsulated with ATTR_TYPE_FUNC. */ 263 ATTR_TYPE_STR, MAIL_ATTR_SASL_METHOD, sasl_method, 264 ATTR_TYPE_STR, MAIL_ATTR_SASL_USERNAME, sasl_username, 265 ATTR_TYPE_STR, MAIL_ATTR_SASL_SENDER, sasl_sender, 266 /* XXX Ditto if we want to pass TLS certificate info. */ 267 ATTR_TYPE_STR, MAIL_ATTR_LOG_IDENT, log_ident, 268 ATTR_TYPE_STR, MAIL_ATTR_RWR_CONTEXT, rewrite_context, 269 ATTR_TYPE_INT, MAIL_ATTR_RCPT_COUNT, &rcpt_count, 270 ATTR_TYPE_END) != 22) { 271 msg_warn("%s: error receiving common attributes", myname); 272 return (-1); 273 } 274 if (mail_open_ok(vstring_str(queue_name), 275 vstring_str(queue_id), &st, &path) == 0) 276 return (-1); 277 278 /* Don't override hand-off time after deliver_pass() delegation. */ 279 if (request->msg_stats.agent_handoff.tv_sec == 0) 280 GETTIMEOFDAY(&request->msg_stats.agent_handoff); 281 282 request->queue_name = mystrdup(vstring_str(queue_name)); 283 request->queue_id = mystrdup(vstring_str(queue_id)); 284 request->nexthop = mystrdup(vstring_str(nexthop)); 285 request->encoding = mystrdup(vstring_str(encoding)); 286 request->sender = mystrdup(vstring_str(address)); 287 request->client_name = mystrdup(vstring_str(client_name)); 288 request->client_addr = mystrdup(vstring_str(client_addr)); 289 request->client_port = mystrdup(vstring_str(client_port)); 290 request->client_proto = mystrdup(vstring_str(client_proto)); 291 request->client_helo = mystrdup(vstring_str(client_helo)); 292 request->sasl_method = mystrdup(vstring_str(sasl_method)); 293 request->sasl_username = mystrdup(vstring_str(sasl_username)); 294 request->sasl_sender = mystrdup(vstring_str(sasl_sender)); 295 request->log_ident = mystrdup(vstring_str(log_ident)); 296 request->rewrite_context = mystrdup(vstring_str(rewrite_context)); 297 request->dsn_envid = mystrdup(vstring_str(dsn_envid)); 298 request->dsn_ret = dsn_ret; 299 300 /* 301 * Extract the recipient offset and address list. Skip over any 302 * attributes from the sender that we do not understand. 303 */ 304 while (rcpt_count-- > 0) { 305 if (attr_scan(stream, ATTR_FLAG_STRICT, 306 ATTR_TYPE_FUNC, rcpb_scan, (void *) rcpt_buf, 307 ATTR_TYPE_END) != 1) { 308 msg_warn("%s: error receiving recipient attributes", myname); 309 return (-1); 310 } 311 recipient_list_add(&request->rcpt_list, rcpt_buf->offset, 312 vstring_str(rcpt_buf->dsn_orcpt), 313 rcpt_buf->dsn_notify, 314 vstring_str(rcpt_buf->orig_addr), 315 vstring_str(rcpt_buf->address)); 316 } 317 if (request->rcpt_list.len <= 0) { 318 msg_warn("%s: no recipients in delivery request for destination %s", 319 request->queue_id, request->nexthop); 320 return (-1); 321 } 322 323 /* 324 * Open the queue file and set a shared lock, in order to prevent 325 * duplicate deliveries when the queue is flushed immediately after queue 326 * manager restart. 327 * 328 * The queue manager locks the file exclusively when it enters the active 329 * queue, and releases the lock before starting deliveries from that 330 * file. The queue manager does not lock the file again when reading more 331 * recipients into memory. When the queue manager is restarted, the new 332 * process moves files from the active queue to the incoming queue to 333 * cool off for a while. Delivery agents should therefore never try to 334 * open a file that is locked by a queue manager process. 335 * 336 * Opening the queue file can fail for a variety of reasons, such as the 337 * system running out of resources. Instead of throwing away mail, we're 338 * raising a fatal error which forces the mail system to back off, and 339 * retry later. 340 */ 341#define DELIVER_LOCK_MODE (MYFLOCK_OP_SHARED | MYFLOCK_OP_NOWAIT) 342 343 request->fp = 344 mail_queue_open(request->queue_name, request->queue_id, O_RDWR, 0); 345 if (request->fp == 0) { 346 if (errno != ENOENT) 347 msg_fatal("open %s %s: %m", request->queue_name, request->queue_id); 348 msg_warn("open %s %s: %m", request->queue_name, request->queue_id); 349 return (-1); 350 } 351 if (msg_verbose) 352 msg_info("%s: file %s", myname, VSTREAM_PATH(request->fp)); 353 if (myflock(vstream_fileno(request->fp), INTERNAL_LOCK, DELIVER_LOCK_MODE) < 0) 354 msg_fatal("shared lock %s: %m", VSTREAM_PATH(request->fp)); 355 close_on_exec(vstream_fileno(request->fp), CLOSE_ON_EXEC); 356 357 return (0); 358} 359 360/* deliver_request_alloc - allocate delivery request structure */ 361 362static DELIVER_REQUEST *deliver_request_alloc(void) 363{ 364 DELIVER_REQUEST *request; 365 366 request = (DELIVER_REQUEST *) mymalloc(sizeof(*request)); 367 request->fp = 0; 368 request->queue_name = 0; 369 request->queue_id = 0; 370 request->nexthop = 0; 371 request->encoding = 0; 372 request->sender = 0; 373 request->data_offset = 0; 374 request->data_size = 0; 375 recipient_list_init(&request->rcpt_list, RCPT_LIST_INIT_STATUS); 376 request->hop_status = 0; 377 request->client_name = 0; 378 request->client_addr = 0; 379 request->client_port = 0; 380 request->client_proto = 0; 381 request->client_helo = 0; 382 request->sasl_method = 0; 383 request->sasl_username = 0; 384 request->sasl_sender = 0; 385 request->log_ident = 0; 386 request->rewrite_context = 0; 387 request->dsn_envid = 0; 388 return (request); 389} 390 391/* deliver_request_free - clean up delivery request structure */ 392 393static void deliver_request_free(DELIVER_REQUEST *request) 394{ 395 if (request->fp) 396 vstream_fclose(request->fp); 397 if (request->queue_name) 398 myfree(request->queue_name); 399 if (request->queue_id) 400 myfree(request->queue_id); 401 if (request->nexthop) 402 myfree(request->nexthop); 403 if (request->encoding) 404 myfree(request->encoding); 405 if (request->sender) 406 myfree(request->sender); 407 recipient_list_free(&request->rcpt_list); 408 if (request->hop_status) 409 dsn_free(request->hop_status); 410 if (request->client_name) 411 myfree(request->client_name); 412 if (request->client_addr) 413 myfree(request->client_addr); 414 if (request->client_port) 415 myfree(request->client_port); 416 if (request->client_proto) 417 myfree(request->client_proto); 418 if (request->client_helo) 419 myfree(request->client_helo); 420 if (request->sasl_method) 421 myfree(request->sasl_method); 422 if (request->sasl_username) 423 myfree(request->sasl_username); 424 if (request->sasl_sender) 425 myfree(request->sasl_sender); 426 if (request->log_ident) 427 myfree(request->log_ident); 428 if (request->rewrite_context) 429 myfree(request->rewrite_context); 430 if (request->dsn_envid) 431 myfree(request->dsn_envid); 432 myfree((char *) request); 433} 434 435/* deliver_request_read - create and read delivery request */ 436 437DELIVER_REQUEST *deliver_request_read(VSTREAM *stream) 438{ 439 DELIVER_REQUEST *request; 440 441 /* 442 * Tell the queue manager that we are ready for this request. 443 */ 444 if (deliver_request_initial(stream) != 0) 445 return (0); 446 447 /* 448 * Be prepared for the queue manager to change its mind after contacting 449 * us. This can happen when a transport or host goes bad. 450 */ 451 (void) read_wait(vstream_fileno(stream), -1); 452 if (peekfd(vstream_fileno(stream)) <= 0) 453 return (0); 454 455 /* 456 * Allocate and read the queue manager's delivery request. 457 */ 458#define XXX_DEFER_STATUS -1 459 460 request = deliver_request_alloc(); 461 if (deliver_request_get(stream, request) < 0) { 462 deliver_request_done(stream, request, XXX_DEFER_STATUS); 463 request = 0; 464 } 465 return (request); 466} 467 468/* deliver_request_done - finish delivery request */ 469 470int deliver_request_done(VSTREAM *stream, DELIVER_REQUEST *request, int status) 471{ 472 int err; 473 474 err = deliver_request_final(stream, request, status); 475 deliver_request_free(request); 476 return (err); 477} 478