1 /* $NetBSD: tlsproxy.c,v 1.1.1.5 2014/07/06 19:27:57 tron Exp $ */ 2 3 /*++ 4 /* NAME 5 /* tlsproxy 8 6 /* SUMMARY 7 /* Postfix TLS proxy 8 /* SYNOPSIS 9 /* \fBtlsproxy\fR [generic Postfix daemon options] 10 /* DESCRIPTION 11 /* The \fBtlsproxy\fR(8) server implements a server-side TLS 12 /* proxy. It is used by \fBpostscreen\fR(8) to talk SMTP-over-TLS 13 /* with remote SMTP clients that are not whitelisted (including 14 /* clients whose whitelist status has expired), 15 /* but it should also work for non-SMTP protocols. 16 /* 17 /* Although one \fBtlsproxy\fR(8) process can serve multiple 18 /* sessions at the same time, it is a good idea to allow the 19 /* number of processes to increase with load, so that the 20 /* service remains responsive. 21 /* PROTOCOL EXAMPLE 22 /* .ad 23 /* .fi 24 /* The example below concerns \fBpostscreen\fR(8). However, 25 /* the \fBtlsproxy\fR(8) server is agnostic of the application 26 /* protocol, and the example is easily adapted to other 27 /* applications. 28 /* 29 /* After receiving a valid remote SMTP client STARTTLS command, 30 /* the \fBpostscreen\fR(8) server sends the remote SMTP client 31 /* endpoint string, the requested role (server), and the 32 /* requested timeout to \fBtlsproxy\fR(8). \fBpostscreen\fR(8) 33 /* then receives a "TLS available" indication from \fBtlsproxy\fR(8). 34 /* If the TLS service is available, \fBpostscreen\fR(8) sends 35 /* the remote SMTP client file descriptor to \fBtlsproxy\fR(8), 36 /* and sends the plaintext 220 greeting to the remote SMTP 37 /* client. This triggers TLS negotiations between the remote 38 /* SMTP client and \fBtlsproxy\fR(8). Upon completion of the 39 /* TLS-level handshake, \fBtlsproxy\fR(8) translates between 40 /* plaintext from/to \fBpostscreen\fR(8) and ciphertext to/from 41 /* the remote SMTP client. 42 /* SECURITY 43 /* .ad 44 /* .fi 45 /* The \fBtlsproxy\fR(8) server is moderately security-sensitive. 46 /* It talks to untrusted clients on the network. The process 47 /* can be run chrooted at fixed low privilege. 48 /* DIAGNOSTICS 49 /* Problems and transactions are logged to \fBsyslogd\fR(8). 50 /* CONFIGURATION PARAMETERS 51 /* .ad 52 /* .fi 53 /* Changes to \fBmain.cf\fR are not picked up automatically, 54 /* as \fBtlsproxy\fR(8) processes may run for a long time 55 /* depending on mail server load. Use the command "\fBpostfix 56 /* reload\fR" to speed up a change. 57 /* 58 /* The text below provides only a parameter summary. See 59 /* \fBpostconf\fR(5) for more details including examples. 60 /* STARTTLS SUPPORT CONTROLS 61 /* .ad 62 /* .fi 63 /* .IP "\fBtlsproxy_tls_CAfile ($smtpd_tls_CAfile)\fR" 64 /* A file containing (PEM format) CA certificates of root CAs 65 /* trusted to sign either remote SMTP client certificates or intermediate 66 /* CA certificates. 67 /* .IP "\fBtlsproxy_tls_CApath ($smtpd_tls_CApath)\fR" 68 /* A directory containing (PEM format) CA certificates of root CAs 69 /* trusted to sign either remote SMTP client certificates or intermediate 70 /* CA certificates. 71 /* .IP "\fBtlsproxy_tls_always_issue_session_ids ($smtpd_tls_always_issue_session_ids)\fR" 72 /* Force the Postfix \fBtlsproxy\fR(8) server to issue a TLS session id, 73 /* even when TLS session caching is turned off. 74 /* .IP "\fBtlsproxy_tls_ask_ccert ($smtpd_tls_ask_ccert)\fR" 75 /* Ask a remote SMTP client for a client certificate. 76 /* .IP "\fBtlsproxy_tls_ccert_verifydepth ($smtpd_tls_ccert_verifydepth)\fR" 77 /* The verification depth for remote SMTP client certificates. 78 /* .IP "\fBtlsproxy_tls_cert_file ($smtpd_tls_cert_file)\fR" 79 /* File with the Postfix \fBtlsproxy\fR(8) server RSA certificate in PEM 80 /* format. 81 /* .IP "\fBtlsproxy_tls_ciphers ($smtpd_tls_ciphers)\fR" 82 /* The minimum TLS cipher grade that the Postfix \fBtlsproxy\fR(8) server 83 /* will use with opportunistic TLS encryption. 84 /* .IP "\fBtlsproxy_tls_dcert_file ($smtpd_tls_dcert_file)\fR" 85 /* File with the Postfix \fBtlsproxy\fR(8) server DSA certificate in PEM 86 /* format. 87 /* .IP "\fBtlsproxy_tls_dh1024_param_file ($smtpd_tls_dh1024_param_file)\fR" 88 /* File with DH parameters that the Postfix \fBtlsproxy\fR(8) server 89 /* should use with non-export EDH ciphers. 90 /* .IP "\fBtlsproxy_tls_dh512_param_file ($smtpd_tls_dh512_param_file)\fR" 91 /* File with DH parameters that the Postfix \fBtlsproxy\fR(8) server 92 /* should use with export-grade EDH ciphers. 93 /* .IP "\fBtlsproxy_tls_dkey_file ($smtpd_tls_dkey_file)\fR" 94 /* File with the Postfix \fBtlsproxy\fR(8) server DSA private key in PEM 95 /* format. 96 /* .IP "\fBtlsproxy_tls_eccert_file ($smtpd_tls_eccert_file)\fR" 97 /* File with the Postfix \fBtlsproxy\fR(8) server ECDSA certificate in 98 /* PEM format. 99 /* .IP "\fBtlsproxy_tls_eckey_file ($smtpd_tls_eckey_file)\fR" 100 /* File with the Postfix \fBtlsproxy\fR(8) server ECDSA private key in 101 /* PEM format. 102 /* .IP "\fBtlsproxy_tls_eecdh_grade ($smtpd_tls_eecdh_grade)\fR" 103 /* The Postfix \fBtlsproxy\fR(8) server security grade for ephemeral 104 /* elliptic-curve Diffie-Hellman (EECDH) key exchange. 105 /* .IP "\fBtlsproxy_tls_exclude_ciphers ($smtpd_tls_exclude_ciphers)\fR" 106 /* List of ciphers or cipher types to exclude from the \fBtlsproxy\fR(8) 107 /* server cipher list at all TLS security levels. 108 /* .IP "\fBtlsproxy_tls_fingerprint_digest ($smtpd_tls_fingerprint_digest)\fR" 109 /* The message digest algorithm to construct remote SMTP 110 /* client-certificate 111 /* fingerprints. 112 /* .IP "\fBtlsproxy_tls_key_file ($smtpd_tls_key_file)\fR" 113 /* File with the Postfix \fBtlsproxy\fR(8) server RSA private key in PEM 114 /* format. 115 /* .IP "\fBtlsproxy_tls_loglevel ($smtpd_tls_loglevel)\fR" 116 /* Enable additional Postfix \fBtlsproxy\fR(8) server logging of TLS 117 /* activity. 118 /* .IP "\fBtlsproxy_tls_mandatory_ciphers ($smtpd_tls_mandatory_ciphers)\fR" 119 /* The minimum TLS cipher grade that the Postfix \fBtlsproxy\fR(8) server 120 /* will use with mandatory TLS encryption. 121 /* .IP "\fBtlsproxy_tls_mandatory_exclude_ciphers ($smtpd_tls_mandatory_exclude_ciphers)\fR" 122 /* Additional list of ciphers or cipher types to exclude from the 123 /* \fBtlsproxy\fR(8) server cipher list at mandatory TLS security levels. 124 /* .IP "\fBtlsproxy_tls_mandatory_protocols ($smtpd_tls_mandatory_protocols)\fR" 125 /* The SSL/TLS protocols accepted by the Postfix \fBtlsproxy\fR(8) server 126 /* with mandatory TLS encryption. 127 /* .IP "\fBtlsproxy_tls_protocols ($smtpd_tls_protocols)\fR" 128 /* List of TLS protocols that the Postfix \fBtlsproxy\fR(8) server will 129 /* exclude or include with opportunistic TLS encryption. 130 /* .IP "\fBtlsproxy_tls_req_ccert ($smtpd_tls_req_ccert)\fR" 131 /* With mandatory TLS encryption, require a trusted remote SMTP 132 /* client certificate in order to allow TLS connections to proceed. 133 /* .IP "\fBtlsproxy_tls_security_level ($smtpd_tls_security_level)\fR" 134 /* The SMTP TLS security level for the Postfix \fBtlsproxy\fR(8) server; 135 /* when a non-empty value is specified, this overrides the obsolete 136 /* parameters smtpd_use_tls and smtpd_enforce_tls. 137 /* .PP 138 /* Available in Postfix version 2.11 and later: 139 /* .IP "\fBtlsmgr_service_name (tlsmgr)\fR" 140 /* The name of the \fBtlsmgr\fR(8) service entry in master.cf. 141 /* OBSOLETE STARTTLS SUPPORT CONTROLS 142 /* .ad 143 /* .fi 144 /* These parameters are supported for compatibility with 145 /* \fBsmtpd\fR(8) legacy parameters. 146 /* .IP "\fBtlsproxy_use_tls ($smtpd_use_tls)\fR" 147 /* Opportunistic TLS: announce STARTTLS support to remote SMTP clients, 148 /* but do not require that clients use TLS encryption. 149 /* .IP "\fBtlsproxy_enforce_tls ($smtpd_enforce_tls)\fR" 150 /* Mandatory TLS: announce STARTTLS support to remote SMTP clients, and 151 /* require that clients use TLS encryption. 152 /* RESOURCE CONTROLS 153 /* .ad 154 /* .fi 155 /* .IP "\fBtlsproxy_watchdog_timeout (10s)\fR" 156 /* How much time a \fBtlsproxy\fR(8) process may take to process local 157 /* or remote I/O before it is terminated by a built-in watchdog timer. 158 /* MISCELLANEOUS CONTROLS 159 /* .ad 160 /* .fi 161 /* .IP "\fBconfig_directory (see 'postconf -d' output)\fR" 162 /* The default location of the Postfix main.cf and master.cf 163 /* configuration files. 164 /* .IP "\fBprocess_id (read-only)\fR" 165 /* The process ID of a Postfix command or daemon process. 166 /* .IP "\fBprocess_name (read-only)\fR" 167 /* The process name of a Postfix command or daemon process. 168 /* .IP "\fBsyslog_facility (mail)\fR" 169 /* The syslog facility of Postfix logging. 170 /* .IP "\fBsyslog_name (see 'postconf -d' output)\fR" 171 /* The mail system name that is prepended to the process name in syslog 172 /* records, so that "smtpd" becomes, for example, "postfix/smtpd". 173 /* SEE ALSO 174 /* postscreen(8), Postfix zombie blocker 175 /* smtpd(8), Postfix SMTP server 176 /* postconf(5), configuration parameters 177 /* syslogd(5), system logging 178 /* LICENSE 179 /* .ad 180 /* .fi 181 /* The Secure Mailer license must be distributed with this software. 182 /* HISTORY 183 /* .ad 184 /* .fi 185 /* This service was introduced with Postfix version 2.8. 186 /* AUTHOR(S) 187 /* Wietse Venema 188 /* IBM T.J. Watson Research 189 /* P.O. Box 704 190 /* Yorktown Heights, NY 10598, USA 191 /*--*/ 192 193 /* 194 * System library. 195 */ 196 #include <sys_defs.h> 197 198 /* 199 * Utility library. 200 */ 201 #include <msg.h> 202 #include <vstream.h> 203 #include <iostuff.h> 204 #include <nbbio.h> 205 #include <mymalloc.h> 206 207 /* 208 * Global library. 209 */ 210 #include <mail_proto.h> 211 #include <mail_params.h> 212 #include <mail_conf.h> 213 #include <mail_version.h> 214 215 /* 216 * Master library. 217 */ 218 #include <mail_server.h> 219 220 /* 221 * TLS library. 222 */ 223 #ifdef USE_TLS 224 #define TLS_INTERNAL /* XXX */ 225 #include <tls.h> 226 #include <tls_proxy.h> 227 228 /* 229 * Application-specific. 230 */ 231 #include <tlsproxy.h> 232 233 /* 234 * Tunable parameters. We define our clones of the smtpd(8) parameters to 235 * avoid any confusion about which parameters are used by this program. 236 */ 237 int var_smtpd_tls_ccert_vd; 238 char *var_smtpd_tls_loglevel; 239 bool var_smtpd_use_tls; 240 bool var_smtpd_enforce_tls; 241 bool var_smtpd_tls_ask_ccert; 242 bool var_smtpd_tls_req_ccert; 243 bool var_smtpd_tls_set_sessid; 244 char *var_smtpd_relay_ccerts; 245 char *var_smtpd_tls_cert_file; 246 char *var_smtpd_tls_key_file; 247 char *var_smtpd_tls_dcert_file; 248 char *var_smtpd_tls_dkey_file; 249 char *var_smtpd_tls_eccert_file; 250 char *var_smtpd_tls_eckey_file; 251 char *var_smtpd_tls_CAfile; 252 char *var_smtpd_tls_CApath; 253 char *var_smtpd_tls_ciph; 254 char *var_smtpd_tls_mand_ciph; 255 char *var_smtpd_tls_excl_ciph; 256 char *var_smtpd_tls_mand_excl; 257 char *var_smtpd_tls_proto; 258 char *var_smtpd_tls_mand_proto; 259 char *var_smtpd_tls_dh512_param_file; 260 char *var_smtpd_tls_dh1024_param_file; 261 char *var_smtpd_tls_eecdh; 262 char *var_smtpd_tls_fpt_dgst; 263 char *var_smtpd_tls_level; 264 265 int var_tlsp_tls_ccert_vd; 266 char *var_tlsp_tls_loglevel; 267 bool var_tlsp_use_tls; 268 bool var_tlsp_enforce_tls; 269 bool var_tlsp_tls_ask_ccert; 270 bool var_tlsp_tls_req_ccert; 271 bool var_tlsp_tls_set_sessid; 272 char *var_tlsp_tls_cert_file; 273 char *var_tlsp_tls_key_file; 274 char *var_tlsp_tls_dcert_file; 275 char *var_tlsp_tls_dkey_file; 276 char *var_tlsp_tls_eccert_file; 277 char *var_tlsp_tls_eckey_file; 278 char *var_tlsp_tls_CAfile; 279 char *var_tlsp_tls_CApath; 280 char *var_tlsp_tls_ciph; 281 char *var_tlsp_tls_mand_ciph; 282 char *var_tlsp_tls_excl_ciph; 283 char *var_tlsp_tls_mand_excl; 284 char *var_tlsp_tls_proto; 285 char *var_tlsp_tls_mand_proto; 286 char *var_tlsp_tls_dh512_param_file; 287 char *var_tlsp_tls_dh1024_param_file; 288 char *var_tlsp_tls_eecdh; 289 char *var_tlsp_tls_fpt_dgst; 290 char *var_tlsp_tls_level; 291 292 int var_tlsp_watchdog; 293 294 /* 295 * TLS per-process status. 296 */ 297 static TLS_APPL_STATE *tlsp_server_ctx; 298 static int ask_client_cert; 299 300 /* 301 * SLMs. 302 */ 303 #define STR(x) vstring_str(x) 304 305 /* 306 * This code looks simpler than expected. That is the result of a great deal 307 * of effort, mainly in design and analysis. 308 * 309 * By design, postscreen(8) is an event-driven server that must scale up to a 310 * large number of clients. This means that postscreen(8) must avoid doing 311 * CPU-intensive operations such as those in OpenSSL. 312 * 313 * tlsproxy(8) runs the OpenSSL code on behalf of postscreen(8), translating 314 * plaintext SMTP messages from postscreen(8) into SMTP-over-TLS messages to 315 * the remote SMTP client, and vice versa. As long as postscreen(8) does not 316 * receive email messages, the cost of doing TLS operations will be modest. 317 * 318 * Like postscreen(8), one tlsproxy(8) process services multiple remote SMTP 319 * clients. Unlike postscreen(8), there can be more than one tlsproxy(8) 320 * process, although their number is meant to be much smaller than the 321 * number of remote SMTP clients that talk TLS. 322 * 323 * As with postscreen(8), all I/O must be event-driven: encrypted traffic 324 * between tlsproxy(8) and remote SMTP clients, and plaintext traffic 325 * between tlsproxy(8) and postscreen(8). Event-driven plaintext I/O is 326 * straightforward enough that it could be abstracted away with the nbbio(3) 327 * module. 328 * 329 * The event-driven TLS I/O implementation is founded on on-line OpenSSL 330 * documentation, supplemented by statements from OpenSSL developers on 331 * public mailing lists. After some field experience with this code, we may 332 * be able to factor it out as a library module, like nbbio(3), that can 333 * become part of the TLS library. 334 */ 335 336 static void tlsp_ciphertext_event(int, char *); 337 338 #define TLSP_INIT_TIMEOUT 100 339 340 /* tlsp_drain - delayed exit after "postfix reload" */ 341 342 static void tlsp_drain(char *unused_service, char **unused_argv) 343 { 344 int count; 345 346 /* 347 * After "postfix reload", complete work-in-progress in the background, 348 * instead of dropping already-accepted connections on the floor. 349 * 350 * All error retry counts shall be limited. Instead of blocking here, we 351 * could retry failed fork() operations in the event call-back routines, 352 * but we don't need perfection. The host system is severely overloaded 353 * and service levels are already way down. 354 */ 355 for (count = 0; /* see below */ ; count++) { 356 if (count >= 5) { 357 msg_fatal("fork: %m"); 358 } else if (event_server_drain() != 0) { 359 msg_warn("fork: %m"); 360 sleep(1); 361 continue; 362 } else { 363 return; 364 } 365 } 366 } 367 368 /* tlsp_eval_tls_error - translate TLS "error" result into action */ 369 370 static int tlsp_eval_tls_error(TLSP_STATE *state, int err) 371 { 372 int ciphertext_fd = state->ciphertext_fd; 373 374 /* 375 * The ciphertext file descriptor is in non-blocking mode, meaning that 376 * each SSL_accept/connect/read/write/shutdown request may return an 377 * "error" indication that it needs to read or write more ciphertext. The 378 * purpose of this routine is to translate those "error" indications into 379 * the appropriate read/write/timeout event requests. 380 */ 381 switch (err) { 382 383 /* 384 * No error from SSL_read and SSL_write means that the plaintext 385 * output buffer is full and that the plaintext input buffer is 386 * empty. Stop read/write events on the ciphertext stream. Keep the 387 * timer alive as a safety mechanism for the case that the plaintext 388 * pseudothreads get stuck. 389 */ 390 case SSL_ERROR_NONE: 391 if (state->ssl_last_err != SSL_ERROR_NONE) { 392 event_disable_readwrite(ciphertext_fd); 393 event_request_timer(tlsp_ciphertext_event, (char *) state, 394 state->timeout); 395 state->ssl_last_err = SSL_ERROR_NONE; 396 } 397 return (0); 398 399 /* 400 * The TLS engine wants to write to the network. Turn on 401 * write/timeout events on the ciphertext stream. 402 */ 403 case SSL_ERROR_WANT_WRITE: 404 if (state->ssl_last_err == SSL_ERROR_WANT_READ) 405 event_disable_readwrite(ciphertext_fd); 406 if (state->ssl_last_err != SSL_ERROR_WANT_WRITE) { 407 event_enable_write(ciphertext_fd, tlsp_ciphertext_event, 408 (char *) state); 409 state->ssl_last_err = SSL_ERROR_WANT_WRITE; 410 } 411 event_request_timer(tlsp_ciphertext_event, (char *) state, 412 state->timeout); 413 return (0); 414 415 /* 416 * The TLS engine wants to read from the network. Turn on 417 * read/timeout events on the ciphertext stream. 418 */ 419 case SSL_ERROR_WANT_READ: 420 if (state->ssl_last_err == SSL_ERROR_WANT_WRITE) 421 event_disable_readwrite(ciphertext_fd); 422 if (state->ssl_last_err != SSL_ERROR_WANT_READ) { 423 event_enable_read(ciphertext_fd, tlsp_ciphertext_event, 424 (char *) state); 425 state->ssl_last_err = SSL_ERROR_WANT_READ; 426 } 427 event_request_timer(tlsp_ciphertext_event, (char *) state, 428 state->timeout); 429 return (0); 430 431 /* 432 * Some error. Self-destruct. This automagically cleans up all 433 * pending read/write and timeout event requests, making state a 434 * dangling pointer. 435 */ 436 case SSL_ERROR_SSL: 437 tls_print_errors(); 438 /* FALLTHROUGH */ 439 default: 440 tlsp_state_free(state); 441 return (-1); 442 } 443 } 444 445 /* tlsp_strategy - decide what to read or write next. */ 446 447 static void tlsp_strategy(TLSP_STATE *state) 448 { 449 TLS_SESS_STATE *tls_context = state->tls_context; 450 NBBIO *plaintext_buf; 451 int ssl_stat; 452 int ssl_read_err; 453 int ssl_write_err; 454 int handshake_err; 455 456 /* 457 * Be sure to complete the TLS handshake before enabling plain-text I/O. 458 * In case of an unrecoverable error, this automagically cleans up all 459 * pending read/write and timeout event requests. 460 */ 461 if (state->flags & TLSP_FLAG_DO_HANDSHAKE) { 462 ssl_stat = SSL_accept(tls_context->con); 463 if (ssl_stat != 1) { 464 handshake_err = SSL_get_error(tls_context->con, ssl_stat); 465 tlsp_eval_tls_error(state, handshake_err); 466 /* At this point, state could be a dangling pointer. */ 467 return; 468 } 469 if ((state->tls_context = tls_server_post_accept(tls_context)) == 0) { 470 tlsp_state_free(state); 471 return; 472 } 473 if ((state->req_flags & TLS_PROXY_FLAG_SEND_CONTEXT) != 0 474 && (attr_print(state->plaintext_stream, ATTR_FLAG_NONE, 475 ATTR_TYPE_FUNC, tls_proxy_context_print, 476 (char *) state->tls_context, ATTR_TYPE_END) != 0 477 || vstream_fflush(state->plaintext_stream) != 0)) { 478 msg_warn("cannot send TLS context: %m"); 479 tlsp_state_free(state); 480 return; 481 } 482 state->flags &= ~TLSP_FLAG_DO_HANDSHAKE; 483 } 484 485 /* 486 * Shutdown and self-destruct after NBBIO error. This automagically 487 * cleans up all pending read/write and timeout event requests. Before 488 * shutting down TLS, we stop all plain-text I/O events but keep the 489 * NBBIO error flags. 490 */ 491 plaintext_buf = state->plaintext_buf; 492 if (NBBIO_ERROR_FLAGS(plaintext_buf)) { 493 if (NBBIO_ACTIVE_FLAGS(plaintext_buf)) 494 nbbio_disable_readwrite(state->plaintext_buf); 495 ssl_stat = SSL_shutdown(tls_context->con); 496 /* XXX Wait for return value 1 if sessions are to be reused? */ 497 if (ssl_stat < 0) { 498 handshake_err = SSL_get_error(tls_context->con, ssl_stat); 499 tlsp_eval_tls_error(state, handshake_err); 500 /* At this point, state could be a dangling pointer. */ 501 return; 502 } 503 tlsp_state_free(state); 504 return; 505 } 506 507 /* 508 * Try to move data from the plaintext input buffer to the TLS engine. 509 * 510 * XXX We're supposed to repeat the exact same SSL_write() call arguments 511 * after an SSL_ERROR_WANT_READ or SSL_ERROR_WANT_WRITE result. Rumor has 512 * it that this is because each SSL_write() call reads from the buffer 513 * incrementally, and returns > 0 only after the final byte is processed. 514 * Rumor also has it that setting SSL_MODE_ENABLE_PARTIAL_WRITE and 515 * SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER voids this requirement, and that 516 * repeating the request with an increased request size is OK. 517 * Unfortunately all this is not or poorly documented, and one has to 518 * rely on statements from OpenSSL developers in public mailing archives. 519 */ 520 ssl_write_err = SSL_ERROR_NONE; 521 while (NBBIO_READ_PEND(plaintext_buf) > 0) { 522 ssl_stat = SSL_write(tls_context->con, NBBIO_READ_BUF(plaintext_buf), 523 NBBIO_READ_PEND(plaintext_buf)); 524 ssl_write_err = SSL_get_error(tls_context->con, ssl_stat); 525 if (ssl_write_err != SSL_ERROR_NONE) 526 break; 527 /* Allow the plaintext pseudothread to read more data. */ 528 NBBIO_READ_PEND(plaintext_buf) -= ssl_stat; 529 if (NBBIO_READ_PEND(plaintext_buf) > 0) 530 memmove(NBBIO_READ_BUF(plaintext_buf), 531 NBBIO_READ_BUF(plaintext_buf) + ssl_stat, 532 NBBIO_READ_PEND(plaintext_buf)); 533 } 534 535 /* 536 * Try to move data from the TLS engine to the plaintext output buffer. 537 * Note: data may arrive as a side effect of calling SSL_write(), 538 * therefore we call SSL_read() after calling SSL_write(). 539 * 540 * XXX We're supposed to repeat the exact same SSL_read() call arguments 541 * after an SSL_ERROR_WANT_READ or SSL_ERROR_WANT_WRITE result. This 542 * supposedly means that our plaintext writer must not memmove() the 543 * plaintext output buffer until after the SSL_read() call succeeds. For 544 * now I'll ignore this, because 1) SSL_read() is documented to return 545 * the bytes available, instead of returning > 0 only after the entire 546 * buffer is processed like SSL_write() does; and 2) there is no "read" 547 * equivalent of the SSL_R_BAD_WRITE_RETRY, SSL_MODE_ENABLE_PARTIAL_WRITE 548 * or SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER features. 549 */ 550 ssl_read_err = SSL_ERROR_NONE; 551 while (NBBIO_WRITE_PEND(state->plaintext_buf) < NBBIO_BUFSIZE(plaintext_buf)) { 552 ssl_stat = SSL_read(tls_context->con, 553 NBBIO_WRITE_BUF(plaintext_buf) 554 + NBBIO_WRITE_PEND(state->plaintext_buf), 555 NBBIO_BUFSIZE(plaintext_buf) 556 - NBBIO_WRITE_PEND(state->plaintext_buf)); 557 ssl_read_err = SSL_get_error(tls_context->con, ssl_stat); 558 if (ssl_read_err != SSL_ERROR_NONE) 559 break; 560 NBBIO_WRITE_PEND(plaintext_buf) += ssl_stat; 561 } 562 563 /* 564 * Try to enable/disable ciphertext read/write events. If SSL_write() was 565 * satisfied, see if SSL_read() wants to do some work. In case of an 566 * unrecoverable error, this automagically destroys the session state 567 * after cleaning up all pending read/write and timeout event requests. 568 */ 569 if (tlsp_eval_tls_error(state, ssl_write_err != SSL_ERROR_NONE ? 570 ssl_write_err : ssl_read_err) < 0) 571 return; 572 573 /* 574 * Try to enable/disable plaintext read/write events. Basically, if we 575 * have nothing to write to the postscreen(8) server, see if there is 576 * something to read. If the write buffer is empty and the read buffer is 577 * full, suspend plaintext I/O until conditions change (but keep the 578 * timer active, as a safety mechanism in case ciphertext I/O gets 579 * stuck). 580 * 581 * XXX In theory, if the client keeps writing fast enough then we would 582 * never read from postscreen(8), and cause postscreen(8) to block. In 583 * practice, postscreen(8) limits the number of client commands, and thus 584 * postscreen(8)'s output will fit in a kernel buffer. This may not be 585 * true in other scenarios where the tlsproxy(8) server could be used. 586 */ 587 if (NBBIO_WRITE_PEND(plaintext_buf) > 0) { 588 if (NBBIO_ACTIVE_FLAGS(plaintext_buf) & NBBIO_FLAG_READ) 589 nbbio_disable_readwrite(plaintext_buf); 590 if ((NBBIO_ACTIVE_FLAGS(plaintext_buf) & NBBIO_FLAG_WRITE) == 0) 591 nbbio_enable_write(plaintext_buf, state->timeout); 592 } else if (NBBIO_READ_PEND(plaintext_buf) < NBBIO_BUFSIZE(plaintext_buf)) { 593 if (NBBIO_ACTIVE_FLAGS(plaintext_buf) & NBBIO_FLAG_WRITE) 594 nbbio_disable_readwrite(plaintext_buf); 595 if ((NBBIO_ACTIVE_FLAGS(plaintext_buf) & NBBIO_FLAG_READ) == 0) 596 nbbio_enable_read(plaintext_buf, state->timeout); 597 } else { 598 if (NBBIO_ACTIVE_FLAGS(plaintext_buf)) 599 nbbio_slumber(plaintext_buf, state->timeout); 600 } 601 } 602 603 /* tlsp_plaintext_event - plaintext was read/written */ 604 605 static void tlsp_plaintext_event(int event, char *context) 606 { 607 TLSP_STATE *state = (TLSP_STATE *) context; 608 609 /* 610 * Safety alert: the plaintext pseudothreads have "slumbered" for too 611 * long (see code above). This means that the ciphertext pseudothreads 612 * are stuck. 613 */ 614 if ((NBBIO_ERROR_FLAGS(state->plaintext_buf) & NBBIO_FLAG_TIMEOUT) != 0 615 && NBBIO_ACTIVE_FLAGS(state->plaintext_buf) == 0) 616 msg_warn("deadlock on ciphertext stream for %s", state->remote_endpt); 617 618 /* 619 * This is easy, because the NBBIO layer has already done the event 620 * decoding and plaintext I/O for us. All we need to do is decide if we 621 * want to read or write more plaintext. 622 */ 623 tlsp_strategy(state); 624 } 625 626 /* tlsp_ciphertext_event - ciphertext is ready to read/write */ 627 628 static void tlsp_ciphertext_event(int event, char *context) 629 { 630 TLSP_STATE *state = (TLSP_STATE *) context; 631 632 /* 633 * Without a TLS quivalent of the NBBIO layer, we must decode the events 634 * ourselves and do the ciphertext I/O. Then, we can decide if we want to 635 * read or write more ciphertext. 636 */ 637 if (event == EVENT_READ || event == EVENT_WRITE) { 638 tlsp_strategy(state); 639 } else { 640 if (event == EVENT_TIME && state->ssl_last_err == SSL_ERROR_NONE) 641 msg_warn("deadlock on plaintext stream for %s", 642 state->remote_endpt); 643 else 644 msg_warn("ciphertext read/write %s for %s", 645 event == EVENT_TIME ? "timeout" : "error", 646 state->remote_endpt); 647 tlsp_state_free(state); 648 } 649 } 650 651 /* tlsp_start_tls - turn on TLS or force disconnect */ 652 653 static void tlsp_start_tls(TLSP_STATE *state) 654 { 655 TLS_SERVER_START_PROPS props; 656 static char *cipher_grade; 657 static VSTRING *cipher_exclusions; 658 659 /* 660 * The code in this routine is pasted literally from smtpd(8). I am not 661 * going to sanitize this because doing so surely will break things in 662 * unexpected ways. 663 */ 664 665 /* 666 * Perform the before-handshake portion of the per-session initalization. 667 * Pass a null VSTREAM to indicate that this program, will do the 668 * ciphertext I/O, not libtls. 669 * 670 * The cipher grade and exclusions don't change between sessions. Compute 671 * just once and cache. 672 */ 673 #define ADD_EXCLUDE(vstr, str) \ 674 do { \ 675 if (*(str)) \ 676 vstring_sprintf_append((vstr), "%s%s", \ 677 VSTRING_LEN(vstr) ? " " : "", (str)); \ 678 } while (0) 679 680 if (cipher_grade == 0) { 681 cipher_grade = 682 var_tlsp_enforce_tls ? var_tlsp_tls_mand_ciph : var_tlsp_tls_ciph; 683 cipher_exclusions = vstring_alloc(10); 684 ADD_EXCLUDE(cipher_exclusions, var_tlsp_tls_excl_ciph); 685 if (var_tlsp_enforce_tls) 686 ADD_EXCLUDE(cipher_exclusions, var_tlsp_tls_mand_excl); 687 if (ask_client_cert) 688 ADD_EXCLUDE(cipher_exclusions, "aNULL"); 689 } 690 state->tls_context = 691 TLS_SERVER_START(&props, 692 ctx = tlsp_server_ctx, 693 stream = (VSTREAM *) 0,/* unused */ 694 fd = state->ciphertext_fd, 695 timeout = 0, /* unused */ 696 requirecert = (var_tlsp_tls_req_ccert 697 && var_tlsp_enforce_tls), 698 serverid = state->server_id, 699 namaddr = state->remote_endpt, 700 cipher_grade = cipher_grade, 701 cipher_exclusions = STR(cipher_exclusions), 702 mdalg = var_tlsp_tls_fpt_dgst); 703 704 if (state->tls_context == 0) { 705 tlsp_state_free(state); 706 return; 707 } 708 709 /* 710 * XXX Do we care about TLS session rate limits? Good postscreen(8) 711 * clients will occasionally require the tlsproxy to renew their 712 * whitelist status, but bad clients hammering the server can suck up 713 * lots of CPU cycles. Per-client concurrency limits in postscreen(8) 714 * will divert only naive security "researchers". 715 * 716 * XXX Do we care about certificate verification results? Not as long as 717 * postscreen(8) doesn't actually receive email. 718 */ 719 } 720 721 /* tlsp_get_fd_event - receive final postscreen(8) hand-off information */ 722 723 static void tlsp_get_fd_event(int event, char *context) 724 { 725 const char *myname = "tlsp_get_fd_event"; 726 TLSP_STATE *state = (TLSP_STATE *) context; 727 int plaintext_fd = vstream_fileno(state->plaintext_stream); 728 729 /* 730 * At this point we still manually manage plaintext read/write/timeout 731 * events. Disable I/O and timer events. Don't assume that the first 732 * plaintext request will be a read. 733 */ 734 event_disable_readwrite(plaintext_fd); 735 if (event != EVENT_TIME) 736 event_cancel_timer(tlsp_get_fd_event, (char *) state); 737 738 /* 739 * Initialize plaintext-related session state. Once we have this behind 740 * us, the TLSP_STATE destructor will automagically clean up requests for 741 * read/write/timeout events, which makes error recovery easier. 742 * 743 * Register the plaintext event handler for timer cleanup in the TLSP_STATE 744 * destructor. Insert the NBBIO event-driven I/O layer between the 745 * postscreen(8) server and the TLS engine. 746 */ 747 if (event != EVENT_READ 748 || (state->ciphertext_fd = LOCAL_RECV_FD(plaintext_fd)) < 0) { 749 msg_warn("%s: receive SMTP client file descriptor: %m", myname); 750 tlsp_state_free(state); 751 return; 752 } 753 non_blocking(state->ciphertext_fd, NON_BLOCKING); 754 state->ciphertext_timer = tlsp_ciphertext_event; 755 state->plaintext_buf = nbbio_create(plaintext_fd, 756 VSTREAM_BUFSIZE, "postscreen", 757 tlsp_plaintext_event, 758 (char *) state); 759 760 /* 761 * Perform the TLS layer before-handshake initialization. We perform the 762 * remainder after the TLS handshake completes. 763 */ 764 tlsp_start_tls(state); 765 766 /* 767 * Trigger the initial proxy server I/Os. 768 */ 769 tlsp_strategy(state); 770 } 771 772 /* tlsp_get_request_event - receive initial postscreen(8) hand-off info */ 773 774 static void tlsp_get_request_event(int event, char *context) 775 { 776 const char *myname = "tlsp_get_request_event"; 777 TLSP_STATE *state = (TLSP_STATE *) context; 778 VSTREAM *plaintext_stream = state->plaintext_stream; 779 int plaintext_fd = vstream_fileno(plaintext_stream); 780 static VSTRING *remote_endpt; 781 static VSTRING *server_id; 782 int req_flags; 783 int timeout; 784 int ready; 785 786 /* 787 * One-time initialization. 788 */ 789 if (remote_endpt == 0) { 790 remote_endpt = vstring_alloc(10); 791 server_id = vstring_alloc(10); 792 } 793 794 /* 795 * At this point we still manually manage plaintext read/write/timeout 796 * events. Turn off timer events. Below we disable read events on error, 797 * and redefine read events on success. 798 */ 799 if (event != EVENT_TIME) 800 event_cancel_timer(tlsp_get_request_event, (char *) state); 801 802 /* 803 * We must send some data, after receiving the request attributes and 804 * before receiving the remote file descriptor. We can't assume 805 * UNIX-domain socket semantics here. 806 */ 807 if (event != EVENT_READ 808 || attr_scan(plaintext_stream, ATTR_FLAG_STRICT, 809 ATTR_TYPE_STR, MAIL_ATTR_REMOTE_ENDPT, remote_endpt, 810 ATTR_TYPE_INT, MAIL_ATTR_FLAGS, &req_flags, 811 ATTR_TYPE_INT, MAIL_ATTR_TIMEOUT, &timeout, 812 ATTR_TYPE_STR, MAIL_ATTR_SERVER_ID, server_id, 813 ATTR_TYPE_END) != 4) { 814 msg_warn("%s: receive request attributes: %m", myname); 815 event_disable_readwrite(plaintext_fd); 816 tlsp_state_free(state); 817 return; 818 } 819 820 /* 821 * If the requested TLS engine is unavailable, hang up after making sure 822 * that the plaintext peer has received our "sorry" indication. 823 */ 824 ready = ((req_flags & TLS_PROXY_FLAG_ROLE_SERVER) != 0 825 && tlsp_server_ctx != 0); 826 if (attr_print(plaintext_stream, ATTR_FLAG_NONE, 827 ATTR_TYPE_INT, MAIL_ATTR_STATUS, ready, 828 ATTR_TYPE_END) != 0 829 || vstream_fflush(plaintext_stream) != 0 830 || ready == 0) { 831 read_wait(plaintext_fd, TLSP_INIT_TIMEOUT); /* XXX */ 832 event_disable_readwrite(plaintext_fd); 833 tlsp_state_free(state); 834 return; 835 } 836 837 /* 838 * XXX We use the same fixed timeout throughout the entire session for 839 * both plaintext and ciphertext communication. This timeout is just a 840 * safety feature; the real timeout will be enforced by our plaintext 841 * peer. 842 */ 843 else { 844 state->remote_endpt = mystrdup(STR(remote_endpt)); 845 state->server_id = mystrdup(STR(server_id)); 846 msg_info("CONNECT %s %s", 847 (req_flags & TLS_PROXY_FLAG_ROLE_SERVER) ? "from" : 848 (req_flags & TLS_PROXY_FLAG_ROLE_CLIENT) ? "to" : 849 "(bogus_direction)", state->remote_endpt); 850 state->req_flags = req_flags; 851 state->timeout = timeout + 10; /* XXX */ 852 event_enable_read(plaintext_fd, tlsp_get_fd_event, (char *) state); 853 event_request_timer(tlsp_get_fd_event, (char *) state, 854 TLSP_INIT_TIMEOUT); 855 return; 856 } 857 } 858 859 /* tlsp_service - handle new client connection */ 860 861 static void tlsp_service(VSTREAM *plaintext_stream, 862 char *service, 863 char **argv) 864 { 865 TLSP_STATE *state; 866 int plaintext_fd = vstream_fileno(plaintext_stream); 867 868 /* 869 * Sanity check. This service takes no command-line arguments. 870 */ 871 if (argv[0]) 872 msg_fatal("unexpected command-line argument: %s", argv[0]); 873 874 /* 875 * This program handles multiple connections, so it must not block. We 876 * use event-driven code for all operations that introduce latency. 877 * Except that attribute lists are sent/received synchronously, once the 878 * socket is found to be ready for transmission. 879 */ 880 non_blocking(plaintext_fd, NON_BLOCKING); 881 vstream_control(plaintext_stream, 882 VSTREAM_CTL_PATH, "plaintext", 883 VSTREAM_CTL_TIMEOUT, 5, 884 VSTREAM_CTL_END); 885 886 /* 887 * Receive postscreen's remote SMTP client address/port and socket. 888 */ 889 state = tlsp_state_create(service, plaintext_stream); 890 event_enable_read(plaintext_fd, tlsp_get_request_event, (char *) state); 891 event_request_timer(tlsp_get_request_event, (char *) state, 892 TLSP_INIT_TIMEOUT); 893 } 894 895 /* pre_jail_init - pre-jail initialization */ 896 897 static void pre_jail_init(char *unused_name, char **unused_argv) 898 { 899 TLS_SERVER_INIT_PROPS props; 900 const char *cert_file; 901 int have_server_cert; 902 int no_server_cert_ok; 903 int require_server_cert; 904 905 /* 906 * The code in this routine is pasted literally from smtpd(8). I am not 907 * going to sanitize this because doing so surely will break things in 908 * unexpected ways. 909 */ 910 if (*var_tlsp_tls_level) { 911 switch (tls_level_lookup(var_tlsp_tls_level)) { 912 default: 913 msg_fatal("Invalid TLS level \"%s\"", var_tlsp_tls_level); 914 /* NOTREACHED */ 915 break; 916 case TLS_LEV_SECURE: 917 case TLS_LEV_VERIFY: 918 case TLS_LEV_FPRINT: 919 msg_warn("%s: unsupported TLS level \"%s\", using \"encrypt\"", 920 VAR_TLSP_TLS_LEVEL, var_tlsp_tls_level); 921 /* FALLTHROUGH */ 922 case TLS_LEV_ENCRYPT: 923 var_tlsp_enforce_tls = var_tlsp_use_tls = 1; 924 break; 925 case TLS_LEV_MAY: 926 var_tlsp_enforce_tls = 0; 927 var_tlsp_use_tls = 1; 928 break; 929 case TLS_LEV_NONE: 930 var_tlsp_enforce_tls = var_tlsp_use_tls = 0; 931 break; 932 } 933 } 934 var_tlsp_use_tls = var_tlsp_use_tls || var_tlsp_enforce_tls; 935 if (!var_tlsp_use_tls) { 936 msg_warn("TLS service is requested, but disabled with %s or %s", 937 VAR_TLSP_TLS_LEVEL, VAR_TLSP_USE_TLS); 938 return; 939 } 940 941 /* 942 * Load TLS keys before dropping privileges. 943 * 944 * Can't use anonymous ciphers if we want client certificates. Must use 945 * anonymous ciphers if we have no certificates. 946 */ 947 ask_client_cert = require_server_cert = 948 (var_tlsp_tls_ask_ccert 949 || (var_tlsp_enforce_tls && var_tlsp_tls_req_ccert)); 950 if (strcasecmp(var_tlsp_tls_cert_file, "none") == 0) { 951 no_server_cert_ok = 1; 952 cert_file = ""; 953 } else { 954 no_server_cert_ok = 0; 955 cert_file = var_tlsp_tls_cert_file; 956 } 957 have_server_cert = 958 (*cert_file || *var_tlsp_tls_dcert_file || *var_tlsp_tls_eccert_file); 959 960 /* Some TLS configuration errors are not show stoppers. */ 961 if (!have_server_cert && require_server_cert) 962 msg_warn("Need a server cert to request client certs"); 963 if (!var_tlsp_enforce_tls && var_tlsp_tls_req_ccert) 964 msg_warn("Can't require client certs unless TLS is required"); 965 /* After a show-stopper error, log a warning. */ 966 if (have_server_cert || (no_server_cert_ok && !require_server_cert)) 967 968 /* 969 * Large parameter lists are error-prone, so we emulate a language 970 * feature that C does not have natively: named parameter lists. 971 */ 972 tlsp_server_ctx = 973 TLS_SERVER_INIT(&props, 974 log_param = VAR_TLSP_TLS_LOGLEVEL, 975 log_level = var_tlsp_tls_loglevel, 976 verifydepth = var_tlsp_tls_ccert_vd, 977 cache_type = TLS_MGR_SCACHE_SMTPD, 978 set_sessid = var_tlsp_tls_set_sessid, 979 cert_file = cert_file, 980 key_file = var_tlsp_tls_key_file, 981 dcert_file = var_tlsp_tls_dcert_file, 982 dkey_file = var_tlsp_tls_dkey_file, 983 eccert_file = var_tlsp_tls_eccert_file, 984 eckey_file = var_tlsp_tls_eckey_file, 985 CAfile = var_tlsp_tls_CAfile, 986 CApath = var_tlsp_tls_CApath, 987 dh1024_param_file 988 = var_tlsp_tls_dh1024_param_file, 989 dh512_param_file 990 = var_tlsp_tls_dh512_param_file, 991 eecdh_grade = var_tlsp_tls_eecdh, 992 protocols = var_tlsp_enforce_tls ? 993 var_tlsp_tls_mand_proto : 994 var_tlsp_tls_proto, 995 ask_ccert = ask_client_cert, 996 mdalg = var_tlsp_tls_fpt_dgst); 997 else 998 msg_warn("No server certs available. TLS can't be enabled"); 999 1000 /* 1001 * To maintain sanity, allow partial SSL_write() operations, and allow 1002 * SSL_write() buffer pointers to change after a WANT_READ or WANT_WRITE 1003 * result. This is based on OpenSSL developers talking on a mailing list, 1004 * but is not supported by documentation. If this code stops working then 1005 * no-one can be held responsible. 1006 */ 1007 if (tlsp_server_ctx) 1008 SSL_CTX_set_mode(tlsp_server_ctx->ssl_ctx, 1009 SSL_MODE_ENABLE_PARTIAL_WRITE 1010 | SSL_MODE_ACCEPT_MOVING_WRITE_BUFFER); 1011 } 1012 1013 /* post_jail_init - post-jail initialization */ 1014 1015 static void post_jail_init(char *unused_name, char **unused_argv) 1016 { 1017 /* void */ ; 1018 } 1019 1020 MAIL_VERSION_STAMP_DECLARE; 1021 1022 /* main - the main program */ 1023 1024 int main(int argc, char **argv) 1025 { 1026 static const CONFIG_INT_TABLE int_table[] = { 1027 VAR_SMTPD_TLS_CCERT_VD, DEF_SMTPD_TLS_CCERT_VD, &var_smtpd_tls_ccert_vd, 0, 0, 1028 0, 1029 }; 1030 static const CONFIG_NINT_TABLE nint_table[] = { 1031 VAR_TLSP_TLS_CCERT_VD, DEF_TLSP_TLS_CCERT_VD, &var_tlsp_tls_ccert_vd, 0, 0, 1032 0, 1033 }; 1034 static const CONFIG_TIME_TABLE time_table[] = { 1035 VAR_TLSP_WATCHDOG, DEF_TLSP_WATCHDOG, &var_tlsp_watchdog, 10, 0, 1036 0, 1037 }; 1038 static const CONFIG_BOOL_TABLE bool_table[] = { 1039 VAR_SMTPD_USE_TLS, DEF_SMTPD_USE_TLS, &var_smtpd_use_tls, 1040 VAR_SMTPD_ENFORCE_TLS, DEF_SMTPD_ENFORCE_TLS, &var_smtpd_enforce_tls, 1041 VAR_SMTPD_TLS_ACERT, DEF_SMTPD_TLS_ACERT, &var_smtpd_tls_ask_ccert, 1042 VAR_SMTPD_TLS_RCERT, DEF_SMTPD_TLS_RCERT, &var_smtpd_tls_req_ccert, 1043 VAR_SMTPD_TLS_SET_SESSID, DEF_SMTPD_TLS_SET_SESSID, &var_smtpd_tls_set_sessid, 1044 0, 1045 }; 1046 static const CONFIG_NBOOL_TABLE nbool_table[] = { 1047 VAR_TLSP_USE_TLS, DEF_TLSP_USE_TLS, &var_tlsp_use_tls, 1048 VAR_TLSP_ENFORCE_TLS, DEF_TLSP_ENFORCE_TLS, &var_tlsp_enforce_tls, 1049 VAR_TLSP_TLS_ACERT, DEF_TLSP_TLS_ACERT, &var_tlsp_tls_ask_ccert, 1050 VAR_TLSP_TLS_RCERT, DEF_TLSP_TLS_RCERT, &var_tlsp_tls_req_ccert, 1051 VAR_TLSP_TLS_SET_SESSID, DEF_TLSP_TLS_SET_SESSID, &var_tlsp_tls_set_sessid, 1052 0, 1053 }; 1054 static const CONFIG_STR_TABLE str_table[] = { 1055 VAR_SMTPD_TLS_CERT_FILE, DEF_SMTPD_TLS_CERT_FILE, &var_smtpd_tls_cert_file, 0, 0, 1056 VAR_SMTPD_TLS_KEY_FILE, DEF_SMTPD_TLS_KEY_FILE, &var_smtpd_tls_key_file, 0, 0, 1057 VAR_SMTPD_TLS_DCERT_FILE, DEF_SMTPD_TLS_DCERT_FILE, &var_smtpd_tls_dcert_file, 0, 0, 1058 VAR_SMTPD_TLS_DKEY_FILE, DEF_SMTPD_TLS_DKEY_FILE, &var_smtpd_tls_dkey_file, 0, 0, 1059 VAR_SMTPD_TLS_ECCERT_FILE, DEF_SMTPD_TLS_ECCERT_FILE, &var_smtpd_tls_eccert_file, 0, 0, 1060 VAR_SMTPD_TLS_ECKEY_FILE, DEF_SMTPD_TLS_ECKEY_FILE, &var_smtpd_tls_eckey_file, 0, 0, 1061 VAR_SMTPD_TLS_CA_FILE, DEF_SMTPD_TLS_CA_FILE, &var_smtpd_tls_CAfile, 0, 0, 1062 VAR_SMTPD_TLS_CA_PATH, DEF_SMTPD_TLS_CA_PATH, &var_smtpd_tls_CApath, 0, 0, 1063 VAR_SMTPD_TLS_CIPH, DEF_SMTPD_TLS_CIPH, &var_smtpd_tls_ciph, 1, 0, 1064 VAR_SMTPD_TLS_MAND_CIPH, DEF_SMTPD_TLS_MAND_CIPH, &var_smtpd_tls_mand_ciph, 1, 0, 1065 VAR_SMTPD_TLS_EXCL_CIPH, DEF_SMTPD_TLS_EXCL_CIPH, &var_smtpd_tls_excl_ciph, 0, 0, 1066 VAR_SMTPD_TLS_MAND_EXCL, DEF_SMTPD_TLS_MAND_EXCL, &var_smtpd_tls_mand_excl, 0, 0, 1067 VAR_SMTPD_TLS_PROTO, DEF_SMTPD_TLS_PROTO, &var_smtpd_tls_proto, 0, 0, 1068 VAR_SMTPD_TLS_MAND_PROTO, DEF_SMTPD_TLS_MAND_PROTO, &var_smtpd_tls_mand_proto, 0, 0, 1069 VAR_SMTPD_TLS_512_FILE, DEF_SMTPD_TLS_512_FILE, &var_smtpd_tls_dh512_param_file, 0, 0, 1070 VAR_SMTPD_TLS_1024_FILE, DEF_SMTPD_TLS_1024_FILE, &var_smtpd_tls_dh1024_param_file, 0, 0, 1071 VAR_SMTPD_TLS_EECDH, DEF_SMTPD_TLS_EECDH, &var_smtpd_tls_eecdh, 1, 0, 1072 VAR_SMTPD_TLS_FPT_DGST, DEF_SMTPD_TLS_FPT_DGST, &var_smtpd_tls_fpt_dgst, 1, 0, 1073 VAR_SMTPD_TLS_LOGLEVEL, DEF_SMTPD_TLS_LOGLEVEL, &var_smtpd_tls_loglevel, 0, 0, 1074 VAR_SMTPD_TLS_LEVEL, DEF_SMTPD_TLS_LEVEL, &var_smtpd_tls_level, 0, 0, 1075 VAR_TLSP_TLS_CERT_FILE, DEF_TLSP_TLS_CERT_FILE, &var_tlsp_tls_cert_file, 0, 0, 1076 VAR_TLSP_TLS_KEY_FILE, DEF_TLSP_TLS_KEY_FILE, &var_tlsp_tls_key_file, 0, 0, 1077 VAR_TLSP_TLS_DCERT_FILE, DEF_TLSP_TLS_DCERT_FILE, &var_tlsp_tls_dcert_file, 0, 0, 1078 VAR_TLSP_TLS_DKEY_FILE, DEF_TLSP_TLS_DKEY_FILE, &var_tlsp_tls_dkey_file, 0, 0, 1079 VAR_TLSP_TLS_ECCERT_FILE, DEF_TLSP_TLS_ECCERT_FILE, &var_tlsp_tls_eccert_file, 0, 0, 1080 VAR_TLSP_TLS_ECKEY_FILE, DEF_TLSP_TLS_ECKEY_FILE, &var_tlsp_tls_eckey_file, 0, 0, 1081 VAR_TLSP_TLS_CA_FILE, DEF_TLSP_TLS_CA_FILE, &var_tlsp_tls_CAfile, 0, 0, 1082 VAR_TLSP_TLS_CA_PATH, DEF_TLSP_TLS_CA_PATH, &var_tlsp_tls_CApath, 0, 0, 1083 VAR_TLSP_TLS_CIPH, DEF_TLSP_TLS_CIPH, &var_tlsp_tls_ciph, 1, 0, 1084 VAR_TLSP_TLS_MAND_CIPH, DEF_TLSP_TLS_MAND_CIPH, &var_tlsp_tls_mand_ciph, 1, 0, 1085 VAR_TLSP_TLS_EXCL_CIPH, DEF_TLSP_TLS_EXCL_CIPH, &var_tlsp_tls_excl_ciph, 0, 0, 1086 VAR_TLSP_TLS_MAND_EXCL, DEF_TLSP_TLS_MAND_EXCL, &var_tlsp_tls_mand_excl, 0, 0, 1087 VAR_TLSP_TLS_PROTO, DEF_TLSP_TLS_PROTO, &var_tlsp_tls_proto, 0, 0, 1088 VAR_TLSP_TLS_MAND_PROTO, DEF_TLSP_TLS_MAND_PROTO, &var_tlsp_tls_mand_proto, 0, 0, 1089 VAR_TLSP_TLS_512_FILE, DEF_TLSP_TLS_512_FILE, &var_tlsp_tls_dh512_param_file, 0, 0, 1090 VAR_TLSP_TLS_1024_FILE, DEF_TLSP_TLS_1024_FILE, &var_tlsp_tls_dh1024_param_file, 0, 0, 1091 VAR_TLSP_TLS_EECDH, DEF_TLSP_TLS_EECDH, &var_tlsp_tls_eecdh, 1, 0, 1092 VAR_TLSP_TLS_FPT_DGST, DEF_TLSP_TLS_FPT_DGST, &var_tlsp_tls_fpt_dgst, 1, 0, 1093 VAR_TLSP_TLS_LOGLEVEL, DEF_TLSP_TLS_LOGLEVEL, &var_tlsp_tls_loglevel, 0, 0, 1094 VAR_TLSP_TLS_LEVEL, DEF_TLSP_TLS_LEVEL, &var_tlsp_tls_level, 0, 0, 1095 0, 1096 }; 1097 1098 /* 1099 * Fingerprint executables and core dumps. 1100 */ 1101 MAIL_VERSION_STAMP_ALLOCATE; 1102 1103 /* 1104 * Pass control to the single-threaded service skeleton. 1105 */ 1106 event_server_main(argc, argv, tlsp_service, 1107 MAIL_SERVER_INT_TABLE, int_table, 1108 MAIL_SERVER_NINT_TABLE, nint_table, 1109 MAIL_SERVER_STR_TABLE, str_table, 1110 MAIL_SERVER_BOOL_TABLE, bool_table, 1111 MAIL_SERVER_NBOOL_TABLE, nbool_table, 1112 MAIL_SERVER_TIME_TABLE, time_table, 1113 MAIL_SERVER_PRE_INIT, pre_jail_init, 1114 MAIL_SERVER_POST_INIT, post_jail_init, 1115 MAIL_SERVER_SLOW_EXIT, tlsp_drain, 1116 MAIL_SERVER_WATCHDOG, &var_tlsp_watchdog, 1117 0); 1118 } 1119 1120 #else 1121 1122 /* tlsp_service - respond to external trigger(s), non-TLS version */ 1123 1124 static void tlsp_service(VSTREAM *stream, char *unused_service, 1125 char **unused_argv) 1126 { 1127 msg_info("TLS support is not compiled in -- exiting"); 1128 event_server_disconnect(stream); 1129 } 1130 1131 /* main - the main program */ 1132 1133 int main(int argc, char **argv) 1134 { 1135 1136 /* 1137 * We can't simply use msg_fatal() here, because the logging hasn't been 1138 * initialized. The text would disappear because stderr is redirected to 1139 * /dev/null. 1140 * 1141 * We invoke event_server_main() to complete program initialization 1142 * (including logging) and then invoke the tlsp_service() routine to log 1143 * the message that says why this program will not run. 1144 */ 1145 event_server_main(argc, argv, tlsp_service, 1146 0); 1147 } 1148 1149 #endif 1150