1 /* $NetBSD: smtp.h,v 1.4 2022/10/08 16:12:49 christos Exp $ */ 2 3 /*++ 4 /* NAME 5 /* smtp 3h 6 /* SUMMARY 7 /* smtp client program 8 /* SYNOPSIS 9 /* #include "smtp.h" 10 /* DESCRIPTION 11 /* .nf 12 13 /* 14 * System library. 15 */ 16 #include <string.h> 17 18 /* 19 * Utility library. 20 */ 21 #include <vstream.h> 22 #include <vstring.h> 23 #include <argv.h> 24 #include <htable.h> 25 #include <dict.h> 26 27 /* 28 * Global library. 29 */ 30 #include <deliver_request.h> 31 #include <scache.h> 32 #include <string_list.h> 33 #include <maps.h> 34 #include <tok822.h> 35 #include <dsn_buf.h> 36 #include <header_body_checks.h> 37 38 /* 39 * Postfix TLS library. 40 */ 41 #include <tls.h> 42 43 /* 44 * tlsproxy client. 45 */ 46 #include <tls_proxy.h> 47 48 /* 49 * Global iterator support. This is updated by the connection-management 50 * loop, and contains dynamic context that appears in lookup keys for SASL 51 * passwords, TLS policy, cached SMTP connections, and cached TLS session 52 * keys. 53 * 54 * For consistency and maintainability, context that is used in more than one 55 * lookup key is formatted with smtp_key_format(). 56 */ 57 typedef struct SMTP_ITERATOR { 58 /* Public members. */ 59 VSTRING *request_nexthop; /* delivery request nexhop or empty */ 60 VSTRING *dest; /* current nexthop */ 61 VSTRING *host; /* hostname or empty */ 62 VSTRING *addr; /* printable address or empty */ 63 unsigned port; /* network byte order or null */ 64 struct DNS_RR *rr; /* DNS resource record or null */ 65 struct DNS_RR *mx; /* DNS resource record or null */ 66 /* Private members. */ 67 VSTRING *saved_dest; /* saved current nexthop */ 68 struct SMTP_STATE *parent; /* parent linkage */ 69 } SMTP_ITERATOR; 70 71 #define SMTP_ITER_INIT(iter, _dest, _host, _addr, _port, state) do { \ 72 vstring_strcpy((iter)->dest, (_dest)); \ 73 vstring_strcpy((iter)->host, (_host)); \ 74 vstring_strcpy((iter)->addr, (_addr)); \ 75 (iter)->port = (_port); \ 76 (iter)->mx = (iter)->rr = 0; \ 77 vstring_strcpy((iter)->saved_dest, ""); \ 78 (iter)->parent = (state); \ 79 } while (0) 80 81 #define SMTP_ITER_SAVE_DEST(iter) do { \ 82 vstring_strcpy((iter)->saved_dest, STR((iter)->dest)); \ 83 } while (0) 84 85 #define SMTP_ITER_RESTORE_DEST(iter) do { \ 86 vstring_strcpy((iter)->dest, STR((iter)->saved_dest)); \ 87 } while (0) 88 89 /* 90 * TLS Policy support. 91 */ 92 #ifdef USE_TLS 93 94 typedef struct SMTP_TLS_POLICY { 95 int level; /* TLS enforcement level */ 96 char *protocols; /* Acceptable SSL protocols */ 97 char *grade; /* Cipher grade: "export", ... */ 98 VSTRING *exclusions; /* Excluded SSL ciphers */ 99 ARGV *matchargv; /* Cert match patterns */ 100 DSN_BUF *why; /* Lookup error status */ 101 TLS_DANE *dane; /* DANE TLSA digests */ 102 char *sni; /* Optional SNI name when not DANE */ 103 int conn_reuse; /* enable connection reuse */ 104 } SMTP_TLS_POLICY; 105 106 /* 107 * smtp_tls_policy.c 108 */ 109 extern void smtp_tls_list_init(void); 110 extern int smtp_tls_policy_cache_query(DSN_BUF *, SMTP_TLS_POLICY *, SMTP_ITERATOR *); 111 extern void smtp_tls_policy_cache_flush(void); 112 113 /* 114 * Macros must use distinct names for local temporary variables, otherwise 115 * there will be bugs due to shadowing. This happened when an earlier 116 * version of smtp_tls_policy_dummy() invoked smtp_tls_policy_init(), but it 117 * could also happen without macro nesting. 118 * 119 * General principle: use all or part of the macro name in each temporary 120 * variable name. Then, append suffixes to the names if needed. 121 */ 122 #define smtp_tls_policy_dummy(t) do { \ 123 SMTP_TLS_POLICY *_tls_policy_dummy_tmp = (t); \ 124 smtp_tls_policy_init(_tls_policy_dummy_tmp, (DSN_BUF *) 0); \ 125 _tls_policy_dummy_tmp->level = TLS_LEV_NONE; \ 126 } while (0) 127 128 /* This macro is not part of the module external interface. */ 129 #define smtp_tls_policy_init(t, w) do { \ 130 SMTP_TLS_POLICY *_tls_policy_init_tmp = (t); \ 131 _tls_policy_init_tmp->protocols = 0; \ 132 _tls_policy_init_tmp->grade = 0; \ 133 _tls_policy_init_tmp->exclusions = 0; \ 134 _tls_policy_init_tmp->matchargv = 0; \ 135 _tls_policy_init_tmp->why = (w); \ 136 _tls_policy_init_tmp->dane = 0; \ 137 _tls_policy_init_tmp->sni = 0; \ 138 _tls_policy_init_tmp->conn_reuse = 0; \ 139 } while (0) 140 141 #endif 142 143 /* 144 * State information associated with each SMTP delivery request. 145 * Session-specific state is stored separately. 146 */ 147 typedef struct SMTP_STATE { 148 int misc_flags; /* processing flags, see below */ 149 VSTREAM *src; /* queue file stream */ 150 const char *service; /* transport name */ 151 DELIVER_REQUEST *request; /* envelope info, offsets */ 152 struct SMTP_SESSION *session; /* network connection */ 153 int status; /* delivery status */ 154 ssize_t space_left; /* output length control */ 155 156 /* 157 * Global iterator. 158 */ 159 SMTP_ITERATOR iterator[1]; /* Usage: state->iterator->member */ 160 161 /* 162 * Global iterator. 163 */ 164 #ifdef USE_TLS 165 SMTP_TLS_POLICY tls[1]; /* Usage: state->tls->member */ 166 #endif 167 168 /* 169 * Connection cache support. 170 */ 171 HTABLE *cache_used; /* cached addresses that were used */ 172 VSTRING *dest_label; /* cached logical/physical binding */ 173 VSTRING *dest_prop; /* binding properties, passivated */ 174 VSTRING *endp_label; /* cached session physical endpoint */ 175 VSTRING *endp_prop; /* endpoint properties, passivated */ 176 177 /* 178 * Flags and counters to control the handling of mail delivery errors. 179 * There is some redundancy for sanity checking. At the end of an SMTP 180 * session all recipients should be marked one way or the other. 181 */ 182 int rcpt_left; /* recipients left over */ 183 int rcpt_drop; /* recipients marked as drop */ 184 int rcpt_keep; /* recipients marked as keep */ 185 186 /* 187 * DSN Support introduced major bloat in error processing. 188 */ 189 DSN_BUF *why; /* on-the-fly formatting buffer */ 190 191 /* 192 * Whether per-nexthop debug_peer support was requested. Otherwise, 193 * assume per-server debug_peer support. 194 */ 195 int debug_peer_per_nexthop; 196 197 /* 198 * One-bit counters to avoid logging the same warning multiple times per 199 * delivery request. 200 */ 201 int logged_line_length_limit:1; 202 } SMTP_STATE; 203 204 /* 205 * Primitives to enable/disable/test connection caching and reuse based on 206 * the delivery request next-hop destination (i.e. not smtp_fallback_relay). 207 * 208 * Connection cache lookup by the delivery request next-hop destination allows 209 * a reuse request to skip over bad hosts, and may result in a connection to 210 * a fall-back relay. Once we have found a 'good' host for a delivery 211 * request next-hop, clear the delivery request next-hop destination, to 212 * avoid caching less-preferred connections under that same delivery request 213 * next-hop. 214 */ 215 #define SET_SCACHE_REQUEST_NEXTHOP(state, nexthop) do { \ 216 vstring_strcpy((state)->iterator->request_nexthop, nexthop); \ 217 } while (0) 218 219 #define CLEAR_SCACHE_REQUEST_NEXTHOP(state) do { \ 220 STR((state)->iterator->request_nexthop)[0] = 0; \ 221 } while (0) 222 223 #define HAVE_SCACHE_REQUEST_NEXTHOP(state) \ 224 (STR((state)->iterator->request_nexthop)[0] != 0) 225 226 227 /* 228 * Server features. 229 */ 230 #define SMTP_FEATURE_ESMTP (1<<0) 231 #define SMTP_FEATURE_8BITMIME (1<<1) 232 #define SMTP_FEATURE_PIPELINING (1<<2) 233 #define SMTP_FEATURE_SIZE (1<<3) 234 #define SMTP_FEATURE_STARTTLS (1<<4) 235 #define SMTP_FEATURE_AUTH (1<<5) 236 #define SMTP_FEATURE_XFORWARD_NAME (1<<7) 237 #define SMTP_FEATURE_XFORWARD_ADDR (1<<8) 238 #define SMTP_FEATURE_XFORWARD_PROTO (1<<9) 239 #define SMTP_FEATURE_XFORWARD_HELO (1<<10) 240 #define SMTP_FEATURE_XFORWARD_DOMAIN (1<<11) 241 #define SMTP_FEATURE_BEST_MX (1<<12) /* for next-hop or fall-back */ 242 #define SMTP_FEATURE_RSET_REJECTED (1<<13) /* RSET probe rejected */ 243 #define SMTP_FEATURE_FROM_CACHE (1<<14) /* cached connection */ 244 #define SMTP_FEATURE_DSN (1<<15) /* DSN supported */ 245 #define SMTP_FEATURE_PIX_NO_ESMTP (1<<16) /* PIX smtp fixup mode */ 246 #define SMTP_FEATURE_PIX_DELAY_DOTCRLF (1<<17) /* PIX smtp fixup mode */ 247 #define SMTP_FEATURE_XFORWARD_PORT (1<<18) 248 #define SMTP_FEATURE_EARLY_TLS_MAIL_REPLY (1<<19) /* CVE-2009-3555 */ 249 #define SMTP_FEATURE_XFORWARD_IDENT (1<<20) 250 #define SMTP_FEATURE_SMTPUTF8 (1<<21) /* RFC 6531 */ 251 #define SMTP_FEATURE_FROM_PROXY (1<<22) /* proxied connection */ 252 253 /* 254 * Features that passivate under the endpoint. 255 */ 256 #define SMTP_FEATURE_ENDPOINT_MASK \ 257 (~(SMTP_FEATURE_BEST_MX | SMTP_FEATURE_RSET_REJECTED \ 258 | SMTP_FEATURE_FROM_CACHE)) 259 260 /* 261 * Features that passivate under the logical destination. 262 */ 263 #define SMTP_FEATURE_DESTINATION_MASK (SMTP_FEATURE_BEST_MX) 264 265 /* 266 * Misc flags. 267 */ 268 #define SMTP_MISC_FLAG_LOOP_DETECT (1<<0) 269 #define SMTP_MISC_FLAG_IN_STARTTLS (1<<1) 270 #define SMTP_MISC_FLAG_FIRST_NEXTHOP (1<<2) 271 #define SMTP_MISC_FLAG_FINAL_NEXTHOP (1<<3) 272 #define SMTP_MISC_FLAG_FINAL_SERVER (1<<4) 273 #define SMTP_MISC_FLAG_CONN_LOAD (1<<5) 274 #define SMTP_MISC_FLAG_CONN_STORE (1<<6) 275 #define SMTP_MISC_FLAG_COMPLETE_SESSION (1<<7) 276 #define SMTP_MISC_FLAG_PREF_IPV6 (1<<8) 277 #define SMTP_MISC_FLAG_PREF_IPV4 (1<<9) 278 279 #define SMTP_MISC_FLAG_CONN_CACHE_MASK \ 280 (SMTP_MISC_FLAG_CONN_LOAD | SMTP_MISC_FLAG_CONN_STORE) 281 282 /* 283 * smtp.c 284 */ 285 #define SMTP_HAS_DSN(why) (STR((why)->status)[0] != 0) 286 #define SMTP_HAS_SOFT_DSN(why) (STR((why)->status)[0] == '4') 287 #define SMTP_HAS_HARD_DSN(why) (STR((why)->status)[0] == '5') 288 #define SMTP_HAS_LOOP_DSN(why) \ 289 (SMTP_HAS_DSN(why) && strcmp(STR((why)->status) + 1, ".4.6") == 0) 290 291 #define SMTP_SET_SOFT_DSN(why) (STR((why)->status)[0] = '4') 292 #define SMTP_SET_HARD_DSN(why) (STR((why)->status)[0] = '5') 293 294 extern int smtp_host_lookup_mask; /* host lookup methods to use */ 295 296 #define SMTP_HOST_FLAG_DNS (1<<0) 297 #define SMTP_HOST_FLAG_NATIVE (1<<1) 298 299 extern int smtp_dns_support; /* dns support level */ 300 301 #define SMTP_DNS_INVALID (-1) /* smtp_dns_support_level = <bogus> */ 302 #define SMTP_DNS_DISABLED 0 /* smtp_dns_support_level = disabled */ 303 #define SMTP_DNS_ENABLED 1 /* smtp_dns_support_level = enabled */ 304 #define SMTP_DNS_DNSSEC 2 /* smtp_dns_support_level = dnssec */ 305 306 extern SCACHE *smtp_scache; /* connection cache instance */ 307 extern STRING_LIST *smtp_cache_dest; /* cached destinations */ 308 309 extern MAPS *smtp_ehlo_dis_maps; /* ehlo keyword filter */ 310 311 extern MAPS *smtp_pix_bug_maps; /* PIX workarounds */ 312 313 extern MAPS *smtp_generic_maps; /* make internal address valid */ 314 extern int smtp_ext_prop_mask; /* address extension propagation */ 315 extern unsigned smtp_dns_res_opt; /* DNS query flags */ 316 317 #ifdef USE_TLS 318 319 extern TLS_APPL_STATE *smtp_tls_ctx; /* client-side TLS engine */ 320 extern int smtp_tls_insecure_mx_policy; /* DANE post insecure MX? */ 321 322 #endif 323 324 extern HBC_CHECKS *smtp_header_checks; /* limited header checks */ 325 extern HBC_CHECKS *smtp_body_checks; /* limited body checks */ 326 327 /* 328 * smtp_session.c 329 */ 330 331 typedef struct SMTP_SESSION { 332 VSTREAM *stream; /* network connection */ 333 SMTP_ITERATOR *iterator; /* dest, host, addr, port */ 334 char *namaddr; /* mail exchanger */ 335 char *helo; /* helo response */ 336 unsigned port; /* network byte order */ 337 char *namaddrport; /* mail exchanger, incl. port */ 338 339 VSTRING *buffer; /* I/O buffer */ 340 VSTRING *scratch; /* scratch buffer */ 341 VSTRING *scratch2; /* scratch buffer */ 342 343 int features; /* server features */ 344 off_t size_limit; /* server limit or unknown */ 345 346 ARGV *history; /* transaction log */ 347 int error_mask; /* error classes */ 348 struct MIME_STATE *mime_state; /* mime state machine */ 349 350 int send_proto_helo; /* XFORWARD support */ 351 352 time_t expire_time; /* session reuse expiration time */ 353 int reuse_count; /* # of times reused (for logging) */ 354 int forbidden; /* No further I/O allowed */ 355 356 #ifdef USE_SASL_AUTH 357 char *sasl_mechanism_list; /* server mechanism list */ 358 char *sasl_username; /* client username */ 359 char *sasl_passwd; /* client password */ 360 struct XSASL_CLIENT *sasl_client; /* SASL internal state */ 361 VSTRING *sasl_reply; /* client response */ 362 #endif 363 364 /* 365 * TLS related state, don't forget to initialize in session_tls_init()! 366 */ 367 #ifdef USE_TLS 368 TLS_SESS_STATE *tls_context; /* TLS library session state */ 369 char *tls_nexthop; /* Nexthop domain for cert checks */ 370 int tls_retry_plain; /* Try plain when TLS handshake fails */ 371 #endif 372 373 SMTP_STATE *state; /* back link */ 374 } SMTP_SESSION; 375 376 extern SMTP_SESSION *smtp_session_alloc(VSTREAM *, SMTP_ITERATOR *, time_t, int); 377 extern void smtp_session_new_stream(SMTP_SESSION *, VSTREAM *, time_t, int); 378 extern int smtp_sess_plaintext_ok(SMTP_ITERATOR *, int); 379 extern void smtp_session_free(SMTP_SESSION *); 380 extern int smtp_session_passivate(SMTP_SESSION *, VSTRING *, VSTRING *); 381 extern SMTP_SESSION *smtp_session_activate(int, SMTP_ITERATOR *, VSTRING *, VSTRING *); 382 383 /* 384 * What's in a name? 385 */ 386 #define SMTP_HNAME(rr) (var_smtp_cname_overr ? (rr)->rname : (rr)->qname) 387 388 /* 389 * smtp_connect.c 390 */ 391 extern int smtp_connect(SMTP_STATE *); 392 393 /* 394 * smtp_proto.c 395 */ 396 extern void smtp_vrfy_init(void); 397 extern int smtp_helo(SMTP_STATE *); 398 extern int smtp_xfer(SMTP_STATE *); 399 extern int smtp_rset(SMTP_STATE *); 400 extern int smtp_quit(SMTP_STATE *); 401 402 extern HBC_CALL_BACKS smtp_hbc_callbacks[]; 403 404 /* 405 * A connection is re-usable if session->expire_time is > 0 and the 406 * expiration time has not been reached. This is subtle because the timer 407 * can expire between sending a command and receiving the reply for that 408 * command. 409 * 410 * But wait, there is more! When SMTP command pipelining is enabled, there are 411 * two protocol loops that execute at very different times: one loop that 412 * generates commands, and one loop that receives replies to those commands. 413 * These will be called "sender loop" and "receiver loop", respectively. At 414 * well-defined protocol synchronization points, the sender loop pauses to 415 * let the receiver loop catch up. 416 * 417 * When we choose to reuse a connection, both the sender and receiver protocol 418 * loops end with "." (mail delivery) or "RSET" (address probe). When we 419 * choose not to reuse, both the sender and receiver protocol loops end with 420 * "QUIT". The problem is that we must make the same protocol choices in 421 * both the sender and receiver loops, even though those loops may execute 422 * at completely different times. 423 * 424 * We "freeze" the choice in the sender loop, just before we generate "." or 425 * "RSET". The reader loop leaves the connection cacheable even if the timer 426 * expires by the time the response arrives. The connection cleanup code 427 * will call smtp_quit() for connections with an expired cache expiration 428 * timer. 429 * 430 * We could have made the programmer's life a lot simpler by not making a 431 * choice at all, and always leaving it up to the connection cleanup code to 432 * call smtp_quit() for connections with an expired cache expiration timer. 433 * 434 * As a general principle, neither the sender loop nor the receiver loop must 435 * modify the connection caching state, if that can affect the receiver 436 * state machine for not-yet processed replies to already-generated 437 * commands. This restriction does not apply when we have to exit the 438 * protocol loops prematurely due to e.g., timeout or connection loss, so 439 * that those pending replies will never be received. 440 * 441 * But wait, there is even more! Only the first good connection for a specific 442 * destination may be cached under both the next-hop destination name and 443 * the server address; connections to alternate servers must be cached under 444 * the server address alone. This means we must distinguish between bad 445 * connections and other reasons why connections cannot be cached. 446 */ 447 #define THIS_SESSION_IS_CACHED \ 448 (!THIS_SESSION_IS_FORBIDDEN && session->expire_time > 0) 449 450 #define THIS_SESSION_IS_EXPIRED \ 451 (THIS_SESSION_IS_CACHED \ 452 && (session->expire_time < vstream_ftime(session->stream) \ 453 || (var_smtp_reuse_count > 0 \ 454 && session->reuse_count >= var_smtp_reuse_count))) 455 456 #define THIS_SESSION_IS_THROTTLED \ 457 (!THIS_SESSION_IS_FORBIDDEN && session->expire_time < 0) 458 459 #define THIS_SESSION_IS_FORBIDDEN \ 460 (session->forbidden != 0) 461 462 /* Bring the bad news. */ 463 464 #define DONT_CACHE_THIS_SESSION \ 465 (session->expire_time = 0) 466 467 #define DONT_CACHE_THROTTLED_SESSION \ 468 (session->expire_time = -1) 469 470 #define DONT_USE_FORBIDDEN_SESSION \ 471 (session->forbidden = 1) 472 473 /* Initialization. */ 474 475 #define USE_NEWBORN_SESSION \ 476 (session->forbidden = 0) 477 478 #define CACHE_THIS_SESSION_UNTIL(when) \ 479 (session->expire_time = (when)) 480 481 /* 482 * Encapsulate the following so that we don't expose details of 483 * connection management and error handling to the SMTP protocol engine. 484 */ 485 #ifdef USE_SASL_AUTH 486 #define HAVE_SASL_CREDENTIALS \ 487 (var_smtp_sasl_enable \ 488 && *var_smtp_sasl_passwd \ 489 && smtp_sasl_passwd_lookup(session)) 490 #else 491 #define HAVE_SASL_CREDENTIALS (0) 492 #endif 493 494 #define PREACTIVE_DELAY \ 495 (session->state->request->msg_stats.active_arrival.tv_sec - \ 496 session->state->request->msg_stats.incoming_arrival.tv_sec) 497 498 #define PLAINTEXT_FALLBACK_OK_AFTER_STARTTLS_FAILURE \ 499 (session->tls_context == 0 \ 500 && state->tls->level == TLS_LEV_MAY \ 501 && PREACTIVE_DELAY >= var_min_backoff_time \ 502 && !HAVE_SASL_CREDENTIALS) 503 504 #define PLAINTEXT_FALLBACK_OK_AFTER_TLS_SESSION_FAILURE \ 505 (session->tls_context != 0 \ 506 && SMTP_RCPT_LEFT(state) > SMTP_RCPT_MARK_COUNT(state) \ 507 && state->tls->level == TLS_LEV_MAY \ 508 && PREACTIVE_DELAY >= var_min_backoff_time \ 509 && !HAVE_SASL_CREDENTIALS) 510 511 /* 512 * XXX The following will not retry recipients that were deferred while the 513 * SMTP_MISC_FLAG_FINAL_SERVER flag was already set. This includes the case 514 * when TLS fails in the middle of a delivery. 515 */ 516 #define RETRY_AS_PLAINTEXT do { \ 517 session->tls_retry_plain = 1; \ 518 state->misc_flags &= ~SMTP_MISC_FLAG_FINAL_SERVER; \ 519 } while (0) 520 521 /* 522 * smtp_chat.c 523 */ 524 typedef struct SMTP_RESP { /* server response */ 525 int code; /* SMTP code */ 526 const char *dsn; /* enhanced status */ 527 char *str; /* full reply */ 528 VSTRING *dsn_buf; /* status buffer */ 529 VSTRING *str_buf; /* reply buffer */ 530 } SMTP_RESP; 531 532 extern void PRINTFLIKE(2, 3) smtp_chat_cmd(SMTP_SESSION *, const char *,...); 533 extern DICT *smtp_chat_resp_filter; 534 extern SMTP_RESP *smtp_chat_resp(SMTP_SESSION *); 535 extern void smtp_chat_init(SMTP_SESSION *); 536 extern void smtp_chat_reset(SMTP_SESSION *); 537 extern void smtp_chat_notify(SMTP_SESSION *); 538 539 #define SMTP_RESP_FAKE(resp, _dsn) \ 540 ((resp)->code = 0, \ 541 (resp)->dsn = (_dsn), \ 542 (resp)->str = DSN_BY_LOCAL_MTA, \ 543 (resp)) 544 545 #define DSN_BY_LOCAL_MTA ((char *) 0) /* DSN issued by local MTA */ 546 547 #define SMTP_RESP_SET_DSN(resp, _dsn) do { \ 548 vstring_strcpy((resp)->dsn_buf, (_dsn)); \ 549 (resp)->dsn = STR((resp)->dsn_buf); \ 550 } while (0) 551 552 /* 553 * These operations implement a redundant mark-and-sweep algorithm that 554 * explicitly accounts for the fate of every recipient. The interface is 555 * documented in smtp_rcpt.c, which also implements the sweeping. The 556 * smtp_trouble.c module does most of the marking after failure. 557 * 558 * When a delivery fails or succeeds, take one of the following actions: 559 * 560 * - Mark the recipient as KEEP (deliver to alternate MTA) and do not update 561 * the delivery request status. 562 * 563 * - Mark the recipient as DROP (remove from delivery request), log whether 564 * delivery succeeded or failed, delete the recipient from the queue file 565 * and/or update defer or bounce logfiles, and update the delivery request 566 * status. 567 * 568 * At the end of a delivery attempt, all recipients must be marked one way or 569 * the other. Failure to do so will trigger a panic. 570 */ 571 #define SMTP_RCPT_STATE_KEEP 1 /* send to backup host */ 572 #define SMTP_RCPT_STATE_DROP 2 /* remove from request */ 573 #define SMTP_RCPT_INIT(state) do { \ 574 (state)->rcpt_drop = (state)->rcpt_keep = 0; \ 575 (state)->rcpt_left = state->request->rcpt_list.len; \ 576 } while (0) 577 578 #define SMTP_RCPT_DROP(state, rcpt) do { \ 579 (rcpt)->u.status = SMTP_RCPT_STATE_DROP; (state)->rcpt_drop++; \ 580 } while (0) 581 582 #define SMTP_RCPT_KEEP(state, rcpt) do { \ 583 (rcpt)->u.status = SMTP_RCPT_STATE_KEEP; (state)->rcpt_keep++; \ 584 } while (0) 585 586 #define SMTP_RCPT_ISMARKED(rcpt) ((rcpt)->u.status != 0) 587 588 #define SMTP_RCPT_LEFT(state) (state)->rcpt_left 589 590 #define SMTP_RCPT_MARK_COUNT(state) ((state)->rcpt_drop + (state)->rcpt_keep) 591 592 extern void smtp_rcpt_cleanup(SMTP_STATE *); 593 extern void smtp_rcpt_done(SMTP_STATE *, SMTP_RESP *, RECIPIENT *); 594 595 /* 596 * smtp_trouble.c 597 */ 598 #define SMTP_THROTTLE 1 599 #define SMTP_NOTHROTTLE 0 600 extern int smtp_sess_fail(SMTP_STATE *); 601 extern int PRINTFLIKE(5, 6) smtp_misc_fail(SMTP_STATE *, int, const char *, 602 SMTP_RESP *, const char *,...); 603 extern void PRINTFLIKE(5, 6) smtp_rcpt_fail(SMTP_STATE *, RECIPIENT *, 604 const char *, SMTP_RESP *, 605 const char *,...); 606 extern int smtp_stream_except(SMTP_STATE *, int, const char *); 607 608 #define smtp_site_fail(state, mta, resp, ...) \ 609 smtp_misc_fail((state), SMTP_THROTTLE, (mta), (resp), __VA_ARGS__) 610 #define smtp_mesg_fail(state, mta, resp, ...) \ 611 smtp_misc_fail((state), SMTP_NOTHROTTLE, (mta), (resp), __VA_ARGS__) 612 613 /* 614 * smtp_unalias.c 615 */ 616 extern const char *smtp_unalias_name(const char *); 617 extern VSTRING *smtp_unalias_addr(VSTRING *, const char *); 618 619 /* 620 * smtp_state.c 621 */ 622 extern SMTP_STATE *smtp_state_alloc(void); 623 extern void smtp_state_free(SMTP_STATE *); 624 625 /* 626 * smtp_map11.c 627 */ 628 extern int smtp_map11_external(VSTRING *, MAPS *, int); 629 extern int smtp_map11_tree(TOK822 *, MAPS *, int); 630 extern int smtp_map11_internal(VSTRING *, MAPS *, int); 631 632 /* 633 * smtp_key.c 634 */ 635 char *smtp_key_prefix(VSTRING *, const char *, SMTP_ITERATOR *, int); 636 637 #define SMTP_KEY_FLAG_SERVICE (1<<0) /* service name */ 638 #define SMTP_KEY_FLAG_SENDER (1<<1) /* sender address */ 639 #define SMTP_KEY_FLAG_REQ_NEXTHOP (1<<2) /* delivery request nexthop */ 640 #define SMTP_KEY_FLAG_CUR_NEXTHOP (1<<3) /* current nexthop */ 641 #define SMTP_KEY_FLAG_HOSTNAME (1<<4) /* remote host name */ 642 #define SMTP_KEY_FLAG_ADDR (1<<5) /* remote address */ 643 #define SMTP_KEY_FLAG_PORT (1<<6) /* remote port */ 644 #define SMTP_KEY_FLAG_TLS_LEVEL (1<<7) /* requested TLS level */ 645 646 #define SMTP_KEY_MASK_ALL \ 647 (SMTP_KEY_FLAG_SERVICE | SMTP_KEY_FLAG_SENDER | \ 648 SMTP_KEY_FLAG_REQ_NEXTHOP | \ 649 SMTP_KEY_FLAG_CUR_NEXTHOP | SMTP_KEY_FLAG_HOSTNAME | \ 650 SMTP_KEY_FLAG_ADDR | SMTP_KEY_FLAG_PORT | SMTP_KEY_FLAG_TLS_LEVEL) 651 652 /* 653 * Conditional lookup-key flags for cached connections that may be 654 * SASL-authenticated with a per-{sender, nexthop, or hostname} credential. 655 * Each bit corresponds to one type of smtp_sasl_password_file lookup key, 656 * and is turned on only when the corresponding main.cf parameter is turned 657 * on. 658 */ 659 #define COND_SASL_SMTP_KEY_FLAG_SENDER \ 660 ((var_smtp_sender_auth && *var_smtp_sasl_passwd) ? \ 661 SMTP_KEY_FLAG_SENDER : 0) 662 663 #define COND_SASL_SMTP_KEY_FLAG_CUR_NEXTHOP \ 664 (*var_smtp_sasl_passwd ? SMTP_KEY_FLAG_CUR_NEXTHOP : 0) 665 666 #ifdef USE_TLS 667 #define COND_TLS_SMTP_KEY_FLAG_CUR_NEXTHOP \ 668 (TLS_MUST_MATCH(state->tls->level) ? SMTP_KEY_FLAG_CUR_NEXTHOP : 0) 669 #else 670 #define COND_TLS_SMTP_KEY_FLAG_CUR_NEXTHOP \ 671 (0) 672 #endif 673 674 #define COND_SASL_SMTP_KEY_FLAG_HOSTNAME \ 675 (*var_smtp_sasl_passwd ? SMTP_KEY_FLAG_HOSTNAME : 0) 676 677 /* 678 * Connection-cache destination lookup key, based on the delivery request 679 * nexthop. The SENDER attribute is a proxy for sender-dependent SASL 680 * credentials (or absence thereof), and prevents false connection sharing 681 * when different SASL credentials may be required for different deliveries 682 * to the same domain and port. Likewise, the delivery request nexthop 683 * (REQ_NEXTHOP) prevents false sharing of TLS identities (the destination 684 * key links only to appropriate endpoint lookup keys). The SERVICE 685 * attribute is a proxy for all request-independent configuration details. 686 */ 687 #define SMTP_KEY_MASK_SCACHE_DEST_LABEL \ 688 (SMTP_KEY_FLAG_SERVICE | COND_SASL_SMTP_KEY_FLAG_SENDER \ 689 | SMTP_KEY_FLAG_REQ_NEXTHOP) 690 691 /* 692 * Connection-cache endpoint lookup key. The SENDER, CUR_NEXTHOP, HOSTNAME, 693 * PORT and TLS_LEVEL attributes are proxies for SASL credentials and TLS 694 * authentication (or absence thereof), and prevent false connection sharing 695 * when different SASL credentials or TLS identities may be required for 696 * different deliveries to the same IP address and port. The SERVICE 697 * attribute is a proxy for all request-independent configuration details. 698 */ 699 #define SMTP_KEY_MASK_SCACHE_ENDP_LABEL \ 700 (SMTP_KEY_FLAG_SERVICE | COND_SASL_SMTP_KEY_FLAG_SENDER \ 701 | COND_SASL_SMTP_KEY_FLAG_CUR_NEXTHOP \ 702 | COND_SASL_SMTP_KEY_FLAG_HOSTNAME \ 703 | COND_TLS_SMTP_KEY_FLAG_CUR_NEXTHOP | SMTP_KEY_FLAG_ADDR | \ 704 SMTP_KEY_FLAG_PORT | SMTP_KEY_FLAG_TLS_LEVEL) 705 706 /* 707 * Silly little macros. 708 */ 709 #define STR(s) vstring_str(s) 710 #define LEN(s) VSTRING_LEN(s) 711 712 extern int smtp_mode; 713 714 #define VAR_LMTP_SMTP(x) (smtp_mode ? VAR_SMTP_##x : VAR_LMTP_##x) 715 #define LMTP_SMTP_SUFFIX(x) (smtp_mode ? x##_SMTP : x##_LMTP) 716 717 /* 718 * Parsed command-line attributes. These do not change during the process 719 * lifetime. 720 */ 721 typedef struct { 722 int flags; /* from flags=, see below */ 723 } SMTP_CLI_ATTR; 724 725 #define SMTP_CLI_FLAG_DELIVERED_TO (1<<0) /* prepend Delivered-To: */ 726 #define SMTP_CLI_FLAG_ORIG_RCPT (1<<1) /* prepend X-Original-To: */ 727 #define SMTP_CLI_FLAG_RETURN_PATH (1<<2) /* prepend Return-Path: */ 728 #define SMTP_CLI_FLAG_FINAL_DELIVERY (1<<3) /* final, not relay */ 729 730 #define SMTP_CLI_MASK_ADD_HEADERS (SMTP_CLI_FLAG_DELIVERED_TO | \ 731 SMTP_CLI_FLAG_ORIG_RCPT | SMTP_CLI_FLAG_RETURN_PATH) 732 733 extern SMTP_CLI_ATTR smtp_cli_attr; 734 735 /* 736 * smtp_misc.c. 737 */ 738 extern void smtp_rewrite_generic_internal(VSTRING *, const char *); 739 extern void smtp_quote_822_address_flags(VSTRING *, const char *, int); 740 extern void smtp_quote_821_address(VSTRING *, const char *); 741 742 /* 743 * header_from_format support, for postmaster notifications. 744 */ 745 extern int smtp_hfrom_format; 746 747 /* LICENSE 748 /* .ad 749 /* .fi 750 /* The Secure Mailer license must be distributed with this software. 751 /* AUTHOR(S) 752 /* Wietse Venema 753 /* IBM T.J. Watson Research 754 /* P.O. Box 704 755 /* Yorktown Heights, NY 10598, USA 756 /* 757 /* Wietse Venema 758 /* Google, Inc. 759 /* 111 8th Avenue 760 /* New York, NY 10011, USA 761 /* 762 /* TLS support originally by: 763 /* Lutz Jaenicke 764 /* BTU Cottbus 765 /* Allgemeine Elektrotechnik 766 /* Universitaetsplatz 3-4 767 /* D-03044 Cottbus, Germany 768 /* 769 /* Victor Duchovni 770 /* Morgan Stanley 771 /*--*/ 772