1 /* $NetBSD: postscreen.c,v 1.3 2020/03/18 19:05:19 christos Exp $ */ 2 3 /*++ 4 /* NAME 5 /* postscreen 8 6 /* SUMMARY 7 /* Postfix zombie blocker 8 /* SYNOPSIS 9 /* \fBpostscreen\fR [generic Postfix daemon options] 10 /* DESCRIPTION 11 /* The Postfix \fBpostscreen\fR(8) server provides additional 12 /* protection against mail server overload. One \fBpostscreen\fR(8) 13 /* process handles multiple inbound SMTP connections, and decides 14 /* which clients may talk to a Postfix SMTP server process. 15 /* By keeping spambots away, \fBpostscreen\fR(8) leaves more 16 /* SMTP server processes available for legitimate clients, and 17 /* delays the onset of server overload conditions. 18 /* 19 /* This program should not be used on SMTP ports that receive 20 /* mail from end-user clients (MUAs). In a typical deployment, 21 /* \fBpostscreen\fR(8) handles the MX service on TCP port 25, and 22 /* \fBsmtpd\fR(8) receives mail from MUAs on the \fBsubmission\fR 23 /* service (TCP port 587) which requires client authentication. 24 /* Alternatively, a site could set up a dedicated, non-postscreen, 25 /* "port 25" server that provides \fBsubmission\fR service and 26 /* client authentication, but no MX service. 27 /* 28 /* \fBpostscreen\fR(8) maintains a temporary whitelist for 29 /* clients that have passed a number of tests. When an SMTP 30 /* client IP address is whitelisted, \fBpostscreen\fR(8) hands 31 /* off the connection immediately to a Postfix SMTP server 32 /* process. This minimizes the overhead for legitimate mail. 33 /* 34 /* By default, \fBpostscreen\fR(8) logs statistics and hands 35 /* off each connection to a Postfix SMTP server process, while 36 /* excluding clients in mynetworks from all tests (primarily, 37 /* to avoid problems with non-standard SMTP implementations 38 /* in network appliances). This default mode blocks no clients, 39 /* and is useful for non-destructive testing. 40 /* 41 /* In a typical production setting, \fBpostscreen\fR(8) is 42 /* configured to reject mail from clients that fail one or 43 /* more tests. \fBpostscreen\fR(8) logs rejected mail with the 44 /* client address, helo, sender and recipient information. 45 /* 46 /* \fBpostscreen\fR(8) is not an SMTP proxy; this is intentional. 47 /* The purpose is to keep spambots away from Postfix SMTP 48 /* server processes, while minimizing overhead for legitimate 49 /* traffic. 50 /* SECURITY 51 /* .ad 52 /* .fi 53 /* The \fBpostscreen\fR(8) server is moderately security-sensitive. 54 /* It talks to untrusted clients on the network. The process 55 /* can be run chrooted at fixed low privilege. 56 /* STANDARDS 57 /* RFC 821 (SMTP protocol) 58 /* RFC 1123 (Host requirements) 59 /* RFC 1652 (8bit-MIME transport) 60 /* RFC 1869 (SMTP service extensions) 61 /* RFC 1870 (Message Size Declaration) 62 /* RFC 1985 (ETRN command) 63 /* RFC 2034 (SMTP Enhanced Status Codes) 64 /* RFC 2821 (SMTP protocol) 65 /* Not: RFC 2920 (SMTP Pipelining) 66 /* RFC 3030 (CHUNKING without BINARYMIME) 67 /* RFC 3207 (STARTTLS command) 68 /* RFC 3461 (SMTP DSN Extension) 69 /* RFC 3463 (Enhanced Status Codes) 70 /* RFC 5321 (SMTP protocol, including multi-line 220 banners) 71 /* DIAGNOSTICS 72 /* Problems and transactions are logged to \fBsyslogd\fR(8) 73 /* or \fBpostlogd\fR(8). 74 /* BUGS 75 /* The \fBpostscreen\fR(8) built-in SMTP protocol engine 76 /* currently does not announce support for AUTH, XCLIENT or 77 /* XFORWARD. 78 /* If you need to make these services available 79 /* on port 25, then do not enable the optional "after 220 80 /* server greeting" tests. 81 /* 82 /* The optional "after 220 server greeting" tests may result in 83 /* unexpected delivery delays from senders that retry email delivery 84 /* from a different IP address. Reason: after passing these tests a 85 /* new client must disconnect, and reconnect from the same IP 86 /* address before it can deliver mail. See POSTSCREEN_README, section 87 /* "Tests after the 220 SMTP server greeting", for a discussion. 88 /* CONFIGURATION PARAMETERS 89 /* .ad 90 /* .fi 91 /* Changes to main.cf are not picked up automatically, as 92 /* \fBpostscreen\fR(8) processes may run for several hours. 93 /* Use the command "postfix reload" after a configuration 94 /* change. 95 /* 96 /* The text below provides only a parameter summary. See 97 /* \fBpostconf\fR(5) for more details including examples. 98 /* 99 /* NOTE: Some \fBpostscreen\fR(8) parameters implement 100 /* stress-dependent behavior. This is supported only when the 101 /* default parameter value is stress-dependent (that is, it 102 /* looks like ${stress?{X}:{Y}}, or it is the $\fIname\fR 103 /* of an smtpd parameter with a stress-dependent default). 104 /* Other parameters always evaluate as if the \fBstress\fR 105 /* parameter value is the empty string. 106 /* COMPATIBILITY CONTROLS 107 /* .ad 108 /* .fi 109 /* .IP "\fBpostscreen_command_filter ($smtpd_command_filter)\fR" 110 /* A mechanism to transform commands from remote SMTP clients. 111 /* .IP "\fBpostscreen_discard_ehlo_keyword_address_maps ($smtpd_discard_ehlo_keyword_address_maps)\fR" 112 /* Lookup tables, indexed by the remote SMTP client address, with 113 /* case insensitive lists of EHLO keywords (pipelining, starttls, auth, 114 /* etc.) that the \fBpostscreen\fR(8) server will not send in the EHLO response 115 /* to a remote SMTP client. 116 /* .IP "\fBpostscreen_discard_ehlo_keywords ($smtpd_discard_ehlo_keywords)\fR" 117 /* A case insensitive list of EHLO keywords (pipelining, starttls, 118 /* auth, etc.) that the \fBpostscreen\fR(8) server will not send in the EHLO 119 /* response to a remote SMTP client. 120 /* .PP 121 /* Available in Postfix version 3.1 and later: 122 /* .IP "\fBdns_ncache_ttl_fix_enable (no)\fR" 123 /* Enable a workaround for future libc incompatibility. 124 /* .PP 125 /* Available in Postfix version 3.4 and later: 126 /* .IP "\fBpostscreen_reject_footer_maps ($smtpd_reject_footer_maps)\fR" 127 /* Optional lookup table for information that is appended after a 4XX 128 /* or 5XX \fBpostscreen\fR(8) server response. 129 /* TROUBLE SHOOTING CONTROLS 130 /* .ad 131 /* .fi 132 /* .IP "\fBpostscreen_expansion_filter (see 'postconf -d' output)\fR" 133 /* List of characters that are permitted in postscreen_reject_footer 134 /* attribute expansions. 135 /* .IP "\fBpostscreen_reject_footer ($smtpd_reject_footer)\fR" 136 /* Optional information that is appended after a 4XX or 5XX 137 /* \fBpostscreen\fR(8) server 138 /* response. 139 /* .IP "\fBsoft_bounce (no)\fR" 140 /* Safety net to keep mail queued that would otherwise be returned to 141 /* the sender. 142 /* BEFORE-POSTSCREEN PROXY AGENT 143 /* .ad 144 /* .fi 145 /* Available in Postfix version 2.10 and later: 146 /* .IP "\fBpostscreen_upstream_proxy_protocol (empty)\fR" 147 /* The name of the proxy protocol used by an optional before-postscreen 148 /* proxy agent. 149 /* .IP "\fBpostscreen_upstream_proxy_timeout (5s)\fR" 150 /* The time limit for the proxy protocol specified with the 151 /* postscreen_upstream_proxy_protocol parameter. 152 /* PERMANENT WHITE/BLACKLIST TEST 153 /* .ad 154 /* .fi 155 /* This test is executed immediately after a remote SMTP client 156 /* connects. If a client is permanently whitelisted, the client 157 /* will be handed off immediately to a Postfix SMTP server 158 /* process. 159 /* .IP "\fBpostscreen_access_list (permit_mynetworks)\fR" 160 /* Permanent white/blacklist for remote SMTP client IP addresses. 161 /* .IP "\fBpostscreen_blacklist_action (ignore)\fR" 162 /* The action that \fBpostscreen\fR(8) takes when a remote SMTP client is 163 /* permanently blacklisted with the postscreen_access_list parameter. 164 /* MAIL EXCHANGER POLICY TESTS 165 /* .ad 166 /* .fi 167 /* When \fBpostscreen\fR(8) is configured to monitor all primary 168 /* and backup MX addresses, it can refuse to whitelist clients 169 /* that connect to a backup MX address only. For small sites, 170 /* this requires configuring primary and backup MX addresses 171 /* on the same MTA. Larger sites would have to share the 172 /* \fBpostscreen\fR(8) cache between primary and backup MTAs, 173 /* which would introduce a common point of failure. 174 /* .IP "\fBpostscreen_whitelist_interfaces (static:all)\fR" 175 /* A list of local \fBpostscreen\fR(8) server IP addresses where a 176 /* non-whitelisted remote SMTP client can obtain \fBpostscreen\fR(8)'s temporary 177 /* whitelist status. 178 /* BEFORE 220 GREETING TESTS 179 /* .ad 180 /* .fi 181 /* These tests are executed before the remote SMTP client 182 /* receives the "220 servername" greeting. If no tests remain 183 /* after the successful completion of this phase, the client 184 /* will be handed off immediately to a Postfix SMTP server 185 /* process. 186 /* .IP "\fBdnsblog_service_name (dnsblog)\fR" 187 /* The name of the \fBdnsblog\fR(8) service entry in master.cf. 188 /* .IP "\fBpostscreen_dnsbl_action (ignore)\fR" 189 /* The action that \fBpostscreen\fR(8) takes when a remote SMTP client's combined 190 /* DNSBL score is equal to or greater than a threshold (as defined 191 /* with the postscreen_dnsbl_sites and postscreen_dnsbl_threshold 192 /* parameters). 193 /* .IP "\fBpostscreen_dnsbl_reply_map (empty)\fR" 194 /* A mapping from actual DNSBL domain name which includes a secret 195 /* password, to the DNSBL domain name that postscreen will reply with 196 /* when it rejects mail. 197 /* .IP "\fBpostscreen_dnsbl_sites (empty)\fR" 198 /* Optional list of DNS white/blacklist domains, filters and weight 199 /* factors. 200 /* .IP "\fBpostscreen_dnsbl_threshold (1)\fR" 201 /* The inclusive lower bound for blocking a remote SMTP client, based on 202 /* its combined DNSBL score as defined with the postscreen_dnsbl_sites 203 /* parameter. 204 /* .IP "\fBpostscreen_greet_action (ignore)\fR" 205 /* The action that \fBpostscreen\fR(8) takes when a remote SMTP client speaks 206 /* before its turn within the time specified with the postscreen_greet_wait 207 /* parameter. 208 /* .IP "\fBpostscreen_greet_banner ($smtpd_banner)\fR" 209 /* The \fItext\fR in the optional "220-\fItext\fR..." server 210 /* response that 211 /* \fBpostscreen\fR(8) sends ahead of the real Postfix SMTP server's "220 212 /* text..." response, in an attempt to confuse bad SMTP clients so 213 /* that they speak before their turn (pre-greet). 214 /* .IP "\fBpostscreen_greet_wait (normal: 6s, overload: 2s)\fR" 215 /* The amount of time that \fBpostscreen\fR(8) will wait for an SMTP 216 /* client to send a command before its turn, and for DNS blocklist 217 /* lookup results to arrive (default: up to 2 seconds under stress, 218 /* up to 6 seconds otherwise). 219 /* .IP "\fBsmtpd_service_name (smtpd)\fR" 220 /* The internal service that \fBpostscreen\fR(8) hands off allowed 221 /* connections to. 222 /* .PP 223 /* Available in Postfix version 2.11 and later: 224 /* .IP "\fBpostscreen_dnsbl_whitelist_threshold (0)\fR" 225 /* Allow a remote SMTP client to skip "before" and "after 220 226 /* greeting" protocol tests, based on its combined DNSBL score as 227 /* defined with the postscreen_dnsbl_sites parameter. 228 /* .PP 229 /* Available in Postfix version 3.0 and later: 230 /* .IP "\fBpostscreen_dnsbl_timeout (10s)\fR" 231 /* The time limit for DNSBL or DNSWL lookups. 232 /* AFTER 220 GREETING TESTS 233 /* .ad 234 /* .fi 235 /* These tests are executed after the remote SMTP client 236 /* receives the "220 servername" greeting. If a client passes 237 /* all tests during this phase, it will receive a 4XX response 238 /* to all RCPT TO commands. After the client reconnects, it 239 /* will be allowed to talk directly to a Postfix SMTP server 240 /* process. 241 /* .IP "\fBpostscreen_bare_newline_action (ignore)\fR" 242 /* The action that \fBpostscreen\fR(8) takes when a remote SMTP client sends 243 /* a bare newline character, that is, a newline not preceded by carriage 244 /* return. 245 /* .IP "\fBpostscreen_bare_newline_enable (no)\fR" 246 /* Enable "bare newline" SMTP protocol tests in the \fBpostscreen\fR(8) 247 /* server. 248 /* .IP "\fBpostscreen_disable_vrfy_command ($disable_vrfy_command)\fR" 249 /* Disable the SMTP VRFY command in the \fBpostscreen\fR(8) daemon. 250 /* .IP "\fBpostscreen_forbidden_commands ($smtpd_forbidden_commands)\fR" 251 /* List of commands that the \fBpostscreen\fR(8) server considers in 252 /* violation of the SMTP protocol. 253 /* .IP "\fBpostscreen_helo_required ($smtpd_helo_required)\fR" 254 /* Require that a remote SMTP client sends HELO or EHLO before 255 /* commencing a MAIL transaction. 256 /* .IP "\fBpostscreen_non_smtp_command_action (drop)\fR" 257 /* The action that \fBpostscreen\fR(8) takes when a remote SMTP client sends 258 /* non-SMTP commands as specified with the postscreen_forbidden_commands 259 /* parameter. 260 /* .IP "\fBpostscreen_non_smtp_command_enable (no)\fR" 261 /* Enable "non-SMTP command" tests in the \fBpostscreen\fR(8) server. 262 /* .IP "\fBpostscreen_pipelining_action (enforce)\fR" 263 /* The action that \fBpostscreen\fR(8) takes when a remote SMTP client 264 /* sends 265 /* multiple commands instead of sending one command and waiting for 266 /* the server to respond. 267 /* .IP "\fBpostscreen_pipelining_enable (no)\fR" 268 /* Enable "pipelining" SMTP protocol tests in the \fBpostscreen\fR(8) 269 /* server. 270 /* CACHE CONTROLS 271 /* .ad 272 /* .fi 273 /* .IP "\fBpostscreen_cache_cleanup_interval (12h)\fR" 274 /* The amount of time between \fBpostscreen\fR(8) cache cleanup runs. 275 /* .IP "\fBpostscreen_cache_map (btree:$data_directory/postscreen_cache)\fR" 276 /* Persistent storage for the \fBpostscreen\fR(8) server decisions. 277 /* .IP "\fBpostscreen_cache_retention_time (7d)\fR" 278 /* The amount of time that \fBpostscreen\fR(8) will cache an expired 279 /* temporary whitelist entry before it is removed. 280 /* .IP "\fBpostscreen_bare_newline_ttl (30d)\fR" 281 /* The amount of time that \fBpostscreen\fR(8) will use the result from 282 /* a successful "bare newline" SMTP protocol test. 283 /* .IP "\fBpostscreen_dnsbl_max_ttl (${postscreen_dnsbl_ttl?{$postscreen_dnsbl_ttl}:{1}}h)\fR" 284 /* The maximum amount of time that \fBpostscreen\fR(8) will use the 285 /* result from a successful DNS-based reputation test before a 286 /* client IP address is required to pass that test again. 287 /* .IP "\fBpostscreen_dnsbl_min_ttl (60s)\fR" 288 /* The minimum amount of time that \fBpostscreen\fR(8) will use the 289 /* result from a successful DNS-based reputation test before a 290 /* client IP address is required to pass that test again. 291 /* .IP "\fBpostscreen_greet_ttl (1d)\fR" 292 /* The amount of time that \fBpostscreen\fR(8) will use the result from 293 /* a successful PREGREET test. 294 /* .IP "\fBpostscreen_non_smtp_command_ttl (30d)\fR" 295 /* The amount of time that \fBpostscreen\fR(8) will use the result from 296 /* a successful "non_smtp_command" SMTP protocol test. 297 /* .IP "\fBpostscreen_pipelining_ttl (30d)\fR" 298 /* The amount of time that \fBpostscreen\fR(8) will use the result from 299 /* a successful "pipelining" SMTP protocol test. 300 /* RESOURCE CONTROLS 301 /* .ad 302 /* .fi 303 /* .IP "\fBline_length_limit (2048)\fR" 304 /* Upon input, long lines are chopped up into pieces of at most 305 /* this length; upon delivery, long lines are reconstructed. 306 /* .IP "\fBpostscreen_client_connection_count_limit ($smtpd_client_connection_count_limit)\fR" 307 /* How many simultaneous connections any remote SMTP client is 308 /* allowed to have 309 /* with the \fBpostscreen\fR(8) daemon. 310 /* .IP "\fBpostscreen_command_count_limit (20)\fR" 311 /* The limit on the total number of commands per SMTP session for 312 /* \fBpostscreen\fR(8)'s built-in SMTP protocol engine. 313 /* .IP "\fBpostscreen_command_time_limit (normal: 300s, overload: 10s)\fR" 314 /* The time limit to read an entire command line with \fBpostscreen\fR(8)'s 315 /* built-in SMTP protocol engine. 316 /* .IP "\fBpostscreen_post_queue_limit ($default_process_limit)\fR" 317 /* The number of clients that can be waiting for service from a 318 /* real Postfix SMTP server process. 319 /* .IP "\fBpostscreen_pre_queue_limit ($default_process_limit)\fR" 320 /* The number of non-whitelisted clients that can be waiting for 321 /* a decision whether they will receive service from a real Postfix 322 /* SMTP server 323 /* process. 324 /* .IP "\fBpostscreen_watchdog_timeout (10s)\fR" 325 /* How much time a \fBpostscreen\fR(8) process may take to respond to 326 /* a remote SMTP client command or to perform a cache operation before it 327 /* is terminated by a built-in watchdog timer. 328 /* STARTTLS CONTROLS 329 /* .ad 330 /* .fi 331 /* .IP "\fBpostscreen_tls_security_level ($smtpd_tls_security_level)\fR" 332 /* The SMTP TLS security level for the \fBpostscreen\fR(8) server; when 333 /* a non-empty value is specified, this overrides the obsolete parameters 334 /* postscreen_use_tls and postscreen_enforce_tls. 335 /* .IP "\fBtlsproxy_service_name (tlsproxy)\fR" 336 /* The name of the \fBtlsproxy\fR(8) service entry in master.cf. 337 /* OBSOLETE STARTTLS SUPPORT CONTROLS 338 /* .ad 339 /* .fi 340 /* These parameters are supported for compatibility with 341 /* \fBsmtpd\fR(8) legacy parameters. 342 /* .IP "\fBpostscreen_use_tls ($smtpd_use_tls)\fR" 343 /* Opportunistic TLS: announce STARTTLS support to remote SMTP clients, 344 /* but do not require that clients use TLS encryption. 345 /* .IP "\fBpostscreen_enforce_tls ($smtpd_enforce_tls)\fR" 346 /* Mandatory TLS: announce STARTTLS support to remote SMTP clients, and 347 /* require that clients use TLS encryption. 348 /* MISCELLANEOUS CONTROLS 349 /* .ad 350 /* .fi 351 /* .IP "\fBconfig_directory (see 'postconf -d' output)\fR" 352 /* The default location of the Postfix main.cf and master.cf 353 /* configuration files. 354 /* .IP "\fBdelay_logging_resolution_limit (2)\fR" 355 /* The maximal number of digits after the decimal point when logging 356 /* sub-second delay values. 357 /* .IP "\fBcommand_directory (see 'postconf -d' output)\fR" 358 /* The location of all postfix administrative commands. 359 /* .IP "\fBmax_idle (100s)\fR" 360 /* The maximum amount of time that an idle Postfix daemon process waits 361 /* for an incoming connection before terminating voluntarily. 362 /* .IP "\fBprocess_id (read-only)\fR" 363 /* The process ID of a Postfix command or daemon process. 364 /* .IP "\fBprocess_name (read-only)\fR" 365 /* The process name of a Postfix command or daemon process. 366 /* .IP "\fBsyslog_facility (mail)\fR" 367 /* The syslog facility of Postfix logging. 368 /* .IP "\fBsyslog_name (see 'postconf -d' output)\fR" 369 /* A prefix that is prepended to the process name in syslog 370 /* records, so that, for example, "smtpd" becomes "prefix/smtpd". 371 /* .PP 372 /* Available in Postfix 3.3 and later: 373 /* .IP "\fBservice_name (read-only)\fR" 374 /* The master.cf service name of a Postfix daemon process. 375 /* .PP 376 /* Available in Postfix 3.5 and later: 377 /* .IP "\fBinfo_log_address_format (external)\fR" 378 /* The email address form that will be used in non-debug logging 379 /* (info, warning, etc.). 380 /* SEE ALSO 381 /* smtpd(8), Postfix SMTP server 382 /* tlsproxy(8), Postfix TLS proxy server 383 /* dnsblog(8), DNS black/whitelist logger 384 /* postlogd(8), Postfix logging 385 /* syslogd(8), system logging 386 /* README FILES 387 /* .ad 388 /* .fi 389 /* Use "\fBpostconf readme_directory\fR" or "\fBpostconf 390 /* html_directory\fR" to locate this information. 391 /* .nf 392 /* .na 393 /* POSTSCREEN_README, Postfix Postscreen Howto 394 /* LICENSE 395 /* .ad 396 /* .fi 397 /* The Secure Mailer license must be distributed with this software. 398 /* HISTORY 399 /* .ad 400 /* .fi 401 /* This service was introduced with Postfix version 2.8. 402 /* 403 /* Many ideas in \fBpostscreen\fR(8) were explored in earlier 404 /* work by Michael Tokarev, in OpenBSD spamd, and in MailChannels 405 /* Traffic Control. 406 /* AUTHOR(S) 407 /* Wietse Venema 408 /* IBM T.J. Watson Research 409 /* P.O. Box 704 410 /* Yorktown Heights, NY 10598, USA 411 /* 412 /* Wietse Venema 413 /* Google, Inc. 414 /* 111 8th Avenue 415 /* New York, NY 10011, USA 416 /*--*/ 417 418 /* System library. */ 419 420 #include <sys_defs.h> 421 #include <sys/stat.h> 422 #include <stdlib.h> 423 424 /* Utility library. */ 425 426 #include <msg.h> 427 #include <mymalloc.h> 428 #include <events.h> 429 #include <myaddrinfo.h> 430 #include <dict_cache.h> 431 #include <set_eugid.h> 432 #include <vstream.h> 433 #include <name_code.h> 434 #include <inet_proto.h> 435 436 /* Global library. */ 437 438 #include <mail_conf.h> 439 #include <mail_params.h> 440 #include <mail_version.h> 441 #include <mail_proto.h> 442 #include <data_redirect.h> 443 #include <string_list.h> 444 445 /* Master server protocols. */ 446 447 #include <mail_server.h> 448 449 /* Application-specific. */ 450 451 #include <postscreen.h> 452 453 /* 454 * Configuration parameters. 455 */ 456 char *var_smtpd_service; 457 char *var_smtpd_banner; 458 bool var_disable_vrfy_cmd; 459 bool var_helo_required; 460 461 char *var_smtpd_cmd_filter; 462 char *var_psc_cmd_filter; 463 464 char *var_smtpd_forbid_cmds; 465 char *var_psc_forbid_cmds; 466 467 char *var_smtpd_ehlo_dis_words; 468 char *var_smtpd_ehlo_dis_maps; 469 char *var_psc_ehlo_dis_words; 470 char *var_psc_ehlo_dis_maps; 471 472 char *var_smtpd_tls_level; 473 bool var_smtpd_use_tls; 474 bool var_smtpd_enforce_tls; 475 char *var_psc_tls_level; 476 bool var_psc_use_tls; 477 bool var_psc_enforce_tls; 478 479 bool var_psc_disable_vrfy; 480 bool var_psc_helo_required; 481 482 char *var_psc_cache_map; 483 int var_psc_cache_scan; 484 int var_psc_cache_ret; 485 int var_psc_post_queue_limit; 486 int var_psc_pre_queue_limit; 487 int var_psc_watchdog; 488 489 char *var_psc_acl; 490 char *var_psc_blist_action; 491 492 char *var_psc_greet_ttl; 493 int var_psc_greet_wait; 494 495 char *var_psc_pregr_banner; 496 char *var_psc_pregr_action; 497 int var_psc_pregr_ttl; 498 499 char *var_psc_dnsbl_sites; 500 char *var_psc_dnsbl_reply; 501 int var_psc_dnsbl_thresh; 502 int var_psc_dnsbl_wthresh; 503 char *var_psc_dnsbl_action; 504 int var_psc_dnsbl_min_ttl; 505 int var_psc_dnsbl_max_ttl; 506 int var_psc_dnsbl_tmout; 507 508 bool var_psc_pipel_enable; 509 char *var_psc_pipel_action; 510 int var_psc_pipel_ttl; 511 512 bool var_psc_nsmtp_enable; 513 char *var_psc_nsmtp_action; 514 int var_psc_nsmtp_ttl; 515 516 bool var_psc_barlf_enable; 517 char *var_psc_barlf_action; 518 int var_psc_barlf_ttl; 519 520 int var_psc_cmd_count; 521 int var_psc_cmd_time; 522 523 char *var_dnsblog_service; 524 char *var_tlsproxy_service; 525 526 char *var_smtpd_rej_footer; 527 char *var_psc_rej_footer; 528 char *var_psc_rej_ftr_maps; 529 530 int var_smtpd_cconn_limit; 531 int var_psc_cconn_limit; 532 533 char *var_smtpd_exp_filter; 534 char *var_psc_exp_filter; 535 536 char *var_psc_wlist_if; 537 char *var_psc_uproxy_proto; 538 int var_psc_uproxy_tmout; 539 540 /* 541 * Global variables. 542 */ 543 int psc_check_queue_length; /* connections being checked */ 544 int psc_post_queue_length; /* being sent to real SMTPD */ 545 DICT_CACHE *psc_cache_map; /* cache table handle */ 546 VSTRING *psc_temp; /* scratchpad */ 547 char *psc_smtpd_service_name; /* path to real SMTPD */ 548 int psc_pregr_action; /* PSC_ACT_DROP/ENFORCE/etc */ 549 int psc_dnsbl_action; /* PSC_ACT_DROP/ENFORCE/etc */ 550 int psc_pipel_action; /* PSC_ACT_DROP/ENFORCE/etc */ 551 int psc_nsmtp_action; /* PSC_ACT_DROP/ENFORCE/etc */ 552 int psc_barlf_action; /* PSC_ACT_DROP/ENFORCE/etc */ 553 int psc_min_ttl; /* Update with new tests! */ 554 STRING_LIST *psc_forbid_cmds; /* CONNECT GET POST */ 555 int psc_stress_greet_wait; /* stressed greet wait */ 556 int psc_normal_greet_wait; /* stressed greet wait */ 557 int psc_stress_cmd_time_limit; /* stressed command limit */ 558 int psc_normal_cmd_time_limit; /* normal command time limit */ 559 int psc_stress; /* stress level */ 560 int psc_lowat_check_queue_length; /* stress low-water mark */ 561 int psc_hiwat_check_queue_length; /* stress high-water mark */ 562 DICT *psc_dnsbl_reply; /* DNSBL name mapper */ 563 HTABLE *psc_client_concurrency; /* per-client concurrency */ 564 565 /* 566 * Local variables and functions. 567 */ 568 static ARGV *psc_acl; /* permanent white/backlist */ 569 static int psc_blist_action; /* PSC_ACT_DROP/ENFORCE/etc */ 570 static ADDR_MATCH_LIST *psc_wlist_if; /* whitelist interfaces */ 571 572 static void psc_endpt_lookup_done(int, VSTREAM *, 573 MAI_HOSTADDR_STR *, MAI_SERVPORT_STR *, 574 MAI_HOSTADDR_STR *, MAI_SERVPORT_STR *); 575 576 /* psc_dump - dump some statistics before exit */ 577 578 static void psc_dump(char *unused_service, char **unused_argv) 579 { 580 581 /* 582 * Dump preliminary cache cleanup statistics when the process commits 583 * suicide while a cache cleanup run is in progress. We can't currently 584 * distinguish between "postfix reload" (we should restart) or "maximal 585 * idle time reached" (we could finish the cache cleanup first). 586 */ 587 if (psc_cache_map) { 588 dict_cache_close(psc_cache_map); 589 psc_cache_map = 0; 590 } 591 } 592 593 /* psc_drain - delayed exit after "postfix reload" */ 594 595 static void psc_drain(char *unused_service, char **unused_argv) 596 { 597 int count; 598 599 /* 600 * After "postfix reload", complete work-in-progress in the background, 601 * instead of dropping already-accepted connections on the floor. 602 * 603 * Unfortunately we must close all writable tables, so we can't store or 604 * look up reputation information. The reason is that we don't have any 605 * multi-writer safety guarantees. We also can't use the single-writer 606 * proxywrite service, because its latency guarantees are too weak. 607 * 608 * All error retry counts shall be limited. Instead of blocking here, we 609 * could retry failed fork() operations in the event call-back routines, 610 * but we don't need perfection. The host system is severely overloaded 611 * and service levels are already way down. 612 * 613 * XXX Some Berkeley DB versions break with close-after-fork. Every new 614 * version is an improvement over its predecessor. 615 * 616 * XXX Don't assume that it is OK to share the same LMDB lockfile descriptor 617 * between different processes. 618 */ 619 if (psc_cache_map != 0 /* XXX && psc_cache_map 620 requires locking */ ) { 621 dict_cache_close(psc_cache_map); 622 psc_cache_map = 0; 623 } 624 for (count = 0; /* see below */ ; count++) { 625 if (count >= 5) { 626 msg_fatal("fork: %m"); 627 } else if (event_server_drain() != 0) { 628 msg_warn("fork: %m"); 629 sleep(1); 630 continue; 631 } else { 632 return; 633 } 634 } 635 } 636 637 /* psc_service - handle new client connection */ 638 639 static void psc_service(VSTREAM *smtp_client_stream, 640 char *unused_service, 641 char **unused_argv) 642 { 643 644 /* 645 * For sanity, require that at least one of INET or INET6 is enabled. 646 * Otherwise, we can't look up interface information, and we can't 647 * convert names or addresses. 648 */ 649 if (inet_proto_info()->ai_family_list[0] == 0) 650 msg_fatal("all network protocols are disabled (%s = %s)", 651 VAR_INET_PROTOCOLS, var_inet_protocols); 652 653 /* 654 * This program handles all incoming connections, so it must not block. 655 * We use event-driven code for all operations that introduce latency. 656 * 657 * Note: instead of using VSTREAM-level timeouts, we enforce limits on the 658 * total amount of time to receive a complete SMTP command line. 659 */ 660 non_blocking(vstream_fileno(smtp_client_stream), NON_BLOCKING); 661 662 /* 663 * Look up the remote SMTP client address and port. 664 */ 665 psc_endpt_lookup(smtp_client_stream, psc_endpt_lookup_done); 666 } 667 668 /* psc_endpt_lookup_done - endpoint lookup completed */ 669 670 static void psc_endpt_lookup_done(int endpt_status, 671 VSTREAM *smtp_client_stream, 672 MAI_HOSTADDR_STR *smtp_client_addr, 673 MAI_SERVPORT_STR *smtp_client_port, 674 MAI_HOSTADDR_STR *smtp_server_addr, 675 MAI_SERVPORT_STR *smtp_server_port) 676 { 677 const char *myname = "psc_endpt_lookup_done"; 678 PSC_STATE *state; 679 const char *stamp_str; 680 int saved_flags; 681 682 /* 683 * Best effort - if this non-blocking write(2) fails, so be it. 684 */ 685 if (endpt_status < 0) { 686 (void) write(vstream_fileno(smtp_client_stream), 687 "421 4.3.2 No system resources\r\n", 688 sizeof("421 4.3.2 No system resources\r\n") - 1); 689 event_server_disconnect(smtp_client_stream); 690 return; 691 } 692 if (msg_verbose > 1) 693 msg_info("%s: sq=%d cq=%d connect from [%s]:%s", 694 myname, psc_post_queue_length, psc_check_queue_length, 695 smtp_client_addr->buf, smtp_client_port->buf); 696 697 msg_info("CONNECT from [%s]:%s to [%s]:%s", 698 smtp_client_addr->buf, smtp_client_port->buf, 699 smtp_server_addr->buf, smtp_server_port->buf); 700 701 /* 702 * Bundle up all the loose session pieces. This zeroes all flags and time 703 * stamps. 704 */ 705 state = psc_new_session_state(smtp_client_stream, smtp_client_addr->buf, 706 smtp_client_port->buf, 707 smtp_server_addr->buf, 708 smtp_server_port->buf); 709 710 /* 711 * Reply with 421 when the client has too many open connections. 712 */ 713 if (var_psc_cconn_limit > 0 714 && state->client_info->concurrency > var_psc_cconn_limit) { 715 msg_info("NOQUEUE: reject: CONNECT from [%s]:%s: too many connections", 716 state->smtp_client_addr, state->smtp_client_port); 717 PSC_DROP_SESSION_STATE(state, 718 "421 4.7.0 Error: too many connections\r\n"); 719 return; 720 } 721 722 /* 723 * Reply with 421 when we can't forward more connections. 724 */ 725 if (var_psc_post_queue_limit > 0 726 && psc_post_queue_length >= var_psc_post_queue_limit) { 727 msg_info("NOQUEUE: reject: CONNECT from [%s]:%s: all server ports busy", 728 state->smtp_client_addr, state->smtp_client_port); 729 PSC_DROP_SESSION_STATE(state, 730 "421 4.3.2 All server ports are busy\r\n"); 731 return; 732 } 733 734 /* 735 * The permanent white/blacklist has highest precedence. 736 */ 737 if (psc_acl != 0) { 738 switch (psc_acl_eval(state, psc_acl, VAR_PSC_ACL)) { 739 740 /* 741 * Permanently blacklisted. 742 */ 743 case PSC_ACL_ACT_BLACKLIST: 744 msg_info("BLACKLISTED [%s]:%s", PSC_CLIENT_ADDR_PORT(state)); 745 PSC_FAIL_SESSION_STATE(state, PSC_STATE_FLAG_BLIST_FAIL); 746 switch (psc_blist_action) { 747 case PSC_ACT_DROP: 748 PSC_DROP_SESSION_STATE(state, 749 "521 5.3.2 Service currently unavailable\r\n"); 750 return; 751 case PSC_ACT_ENFORCE: 752 PSC_ENFORCE_SESSION_STATE(state, 753 "550 5.3.2 Service currently unavailable\r\n"); 754 break; 755 case PSC_ACT_IGNORE: 756 PSC_UNFAIL_SESSION_STATE(state, PSC_STATE_FLAG_BLIST_FAIL); 757 758 /* 759 * Not: PSC_PASS_SESSION_STATE. Repeat this test the next 760 * time. 761 */ 762 break; 763 default: 764 msg_panic("%s: unknown blacklist action value %d", 765 myname, psc_blist_action); 766 } 767 break; 768 769 /* 770 * Permanently whitelisted. 771 */ 772 case PSC_ACL_ACT_WHITELIST: 773 msg_info("WHITELISTED [%s]:%s", PSC_CLIENT_ADDR_PORT(state)); 774 psc_conclude(state); 775 return; 776 777 /* 778 * Other: dunno (don't know) or error. 779 */ 780 default: 781 break; 782 } 783 } 784 785 /* 786 * The temporary whitelist (i.e. the postscreen cache) has the lowest 787 * precedence. This cache contains information about the results of prior 788 * tests. Whitelist the client when all enabled test results are still 789 * valid. 790 */ 791 if ((state->flags & PSC_STATE_MASK_ANY_FAIL) == 0 792 && state->client_info->concurrency == 1 793 && psc_cache_map != 0 794 && (stamp_str = psc_cache_lookup(psc_cache_map, state->smtp_client_addr)) != 0) { 795 saved_flags = state->flags; 796 psc_parse_tests(state, stamp_str, event_time()); 797 state->flags |= saved_flags; 798 if (msg_verbose) 799 msg_info("%s: cached + recent flags: %s", 800 myname, psc_print_state_flags(state->flags, myname)); 801 if ((state->flags & PSC_STATE_MASK_ANY_TODO_FAIL) == 0) { 802 msg_info("PASS OLD [%s]:%s", PSC_CLIENT_ADDR_PORT(state)); 803 psc_conclude(state); 804 return; 805 } 806 } else if (state->client_info->concurrency > 1) { 807 saved_flags = state->flags; 808 psc_todo_tests(state, event_time()); 809 state->flags |= saved_flags; 810 if (msg_verbose) 811 msg_info("%s: new + recent flags: %s", 812 myname, psc_print_state_flags(state->flags, myname)); 813 } else { 814 saved_flags = state->flags; 815 psc_new_tests(state); 816 state->flags |= saved_flags; 817 if (msg_verbose) 818 msg_info("%s: new + recent flags: %s", 819 myname, psc_print_state_flags(state->flags, myname)); 820 } 821 822 /* 823 * Don't whitelist clients that connect to backup MX addresses. Fail 824 * "closed" on error. 825 */ 826 if (addr_match_list_match(psc_wlist_if, smtp_server_addr->buf) == 0) { 827 state->flags |= (PSC_STATE_FLAG_WLIST_FAIL | PSC_STATE_FLAG_NOFORWARD); 828 msg_info("WHITELIST VETO [%s]:%s", PSC_CLIENT_ADDR_PORT(state)); 829 } 830 831 /* 832 * Reply with 421 when we can't analyze more connections. That also means 833 * no deep protocol tests when the noforward flag is raised. 834 */ 835 if (var_psc_pre_queue_limit > 0 836 && psc_check_queue_length - psc_post_queue_length 837 >= var_psc_pre_queue_limit) { 838 msg_info("reject: connect from [%s]:%s: all screening ports busy", 839 state->smtp_client_addr, state->smtp_client_port); 840 PSC_DROP_SESSION_STATE(state, 841 "421 4.3.2 All screening ports are busy\r\n"); 842 return; 843 } 844 845 /* 846 * If the client has no up-to-date results for some tests, do those tests 847 * first. Otherwise, skip the tests and hand off the connection. 848 */ 849 if (state->flags & PSC_STATE_MASK_EARLY_TODO) 850 psc_early_tests(state); 851 else if (state->flags & (PSC_STATE_MASK_SMTPD_TODO | PSC_STATE_FLAG_NOFORWARD)) 852 psc_smtpd_tests(state); 853 else 854 psc_conclude(state); 855 } 856 857 /* psc_cache_validator - validate one cache entry */ 858 859 static int psc_cache_validator(const char *client_addr, 860 const char *stamp_str, 861 void *unused_context) 862 { 863 PSC_STATE dummy_state; 864 PSC_CLIENT_INFO dummy_client_info; 865 866 /* 867 * This function is called by the cache cleanup pseudo thread. 868 * 869 * When an entry is removed from the cache, the client will be reported as 870 * "NEW" in the next session where it passes all tests again. To avoid 871 * silly logging we remove the cache entry only after all tests have 872 * expired longer ago than the cache retention time. 873 */ 874 dummy_state.client_info = &dummy_client_info; 875 psc_parse_tests(&dummy_state, stamp_str, event_time() - var_psc_cache_ret); 876 return ((dummy_state.flags & PSC_STATE_MASK_ANY_TODO) == 0); 877 } 878 879 /* pre_jail_init - pre-jail initialization */ 880 881 static void pre_jail_init(char *unused_name, char **unused_argv) 882 { 883 VSTRING *redirect; 884 885 /* 886 * Open read-only maps before dropping privilege, for consistency with 887 * other Postfix daemons. 888 */ 889 psc_acl_pre_jail_init(var_mynetworks, VAR_PSC_ACL); 890 if (*var_psc_acl) 891 psc_acl = psc_acl_parse(var_psc_acl, VAR_PSC_ACL); 892 /* Ignore smtpd_forbid_cmds lookup errors. Non-critical feature. */ 893 if (*var_psc_forbid_cmds) 894 psc_forbid_cmds = string_list_init(VAR_PSC_FORBID_CMDS, 895 MATCH_FLAG_RETURN, 896 var_psc_forbid_cmds); 897 if (*var_psc_dnsbl_reply) 898 psc_dnsbl_reply = dict_open(var_psc_dnsbl_reply, O_RDONLY, 899 DICT_FLAG_DUP_WARN); 900 901 /* 902 * Never, ever, get killed by a master signal, as that would corrupt the 903 * database when we're in the middle of an update. 904 */ 905 if (setsid() < 0) 906 msg_warn("setsid: %m"); 907 908 /* 909 * Security: don't create root-owned files that contain untrusted data. 910 * And don't create Postfix-owned files in root-owned directories, 911 * either. We want a correct relationship between (file or directory) 912 * ownership and (file or directory) content. To open files before going 913 * to jail, temporarily drop root privileges. 914 */ 915 SAVE_AND_SET_EUGID(var_owner_uid, var_owner_gid); 916 redirect = vstring_alloc(100); 917 918 /* 919 * Keep state in persistent external map. As a safety measure we sync the 920 * database on each update. This hurts on LINUX file systems that sync 921 * all dirty disk blocks whenever any application invokes fsync(). 922 * 923 * Start the cache maintenance pseudo thread after dropping privileges. 924 */ 925 #define PSC_DICT_OPEN_FLAGS (DICT_FLAG_DUP_REPLACE | DICT_FLAG_SYNC_UPDATE | \ 926 DICT_FLAG_OPEN_LOCK) 927 928 if (*var_psc_cache_map) 929 psc_cache_map = 930 dict_cache_open(data_redirect_map(redirect, var_psc_cache_map), 931 O_CREAT | O_RDWR, PSC_DICT_OPEN_FLAGS); 932 933 /* 934 * Clean up and restore privilege. 935 */ 936 vstring_free(redirect); 937 RESTORE_SAVED_EUGID(); 938 939 /* 940 * Initialize the dummy SMTP engine. 941 */ 942 psc_smtpd_pre_jail_init(); 943 } 944 945 /* pre_accept - see if tables have changed */ 946 947 static void pre_accept(char *unused_name, char **unused_argv) 948 { 949 static time_t last_event_time; 950 time_t new_event_time; 951 const char *name; 952 953 /* 954 * If some table has changed then stop accepting new connections. Don't 955 * check the tables more than once a second. 956 */ 957 new_event_time = event_time(); 958 if (new_event_time >= last_event_time + 1 959 && (name = dict_changed_name()) != 0) { 960 msg_info("table %s has changed - finishing in the background", name); 961 event_server_drain(); 962 } else { 963 last_event_time = new_event_time; 964 } 965 } 966 967 /* post_jail_init - post-jail initialization */ 968 969 static void post_jail_init(char *unused_name, char **unused_argv) 970 { 971 const NAME_CODE actions[] = { 972 PSC_NAME_ACT_DROP, PSC_ACT_DROP, 973 PSC_NAME_ACT_ENFORCE, PSC_ACT_ENFORCE, 974 PSC_NAME_ACT_IGNORE, PSC_ACT_IGNORE, 975 PSC_NAME_ACT_CONT, PSC_ACT_IGNORE, /* compatibility */ 976 0, -1, 977 }; 978 int cache_flags; 979 const char *tmp; 980 981 /* 982 * This routine runs after the skeleton code has entered the chroot jail. 983 * Prevent automatic process suicide after a limited number of client 984 * requests. It is OK to terminate after a limited amount of idle time. 985 */ 986 var_use_limit = 0; 987 988 /* 989 * Workaround for parameters whose values may contain "$", and that have 990 * a default of "$parametername". Not sure if it would be a good idea to 991 * always to this in the mail_conf_raw(3) module. 992 */ 993 if (*var_psc_rej_footer == '$' 994 && mail_conf_lookup(var_psc_rej_footer + 1)) { 995 tmp = mail_conf_eval_once(var_psc_rej_footer); 996 myfree(var_psc_rej_footer); 997 var_psc_rej_footer = mystrdup(tmp); 998 } 999 if (*var_psc_exp_filter == '$' 1000 && mail_conf_lookup(var_psc_exp_filter + 1)) { 1001 tmp = mail_conf_eval_once(var_psc_exp_filter); 1002 myfree(var_psc_exp_filter); 1003 var_psc_exp_filter = mystrdup(tmp); 1004 } 1005 1006 /* 1007 * Other one-time initialization. 1008 */ 1009 psc_temp = vstring_alloc(10); 1010 vstring_sprintf(psc_temp, "%s/%s", MAIL_CLASS_PRIVATE, var_smtpd_service); 1011 psc_smtpd_service_name = mystrdup(STR(psc_temp)); 1012 psc_dnsbl_init(); 1013 psc_early_init(); 1014 psc_smtpd_init(); 1015 1016 if ((psc_blist_action = name_code(actions, NAME_CODE_FLAG_NONE, 1017 var_psc_blist_action)) < 0) 1018 msg_fatal("bad %s value: %s", VAR_PSC_BLIST_ACTION, 1019 var_psc_blist_action); 1020 if ((psc_dnsbl_action = name_code(actions, NAME_CODE_FLAG_NONE, 1021 var_psc_dnsbl_action)) < 0) 1022 msg_fatal("bad %s value: %s", VAR_PSC_DNSBL_ACTION, 1023 var_psc_dnsbl_action); 1024 if ((psc_pregr_action = name_code(actions, NAME_CODE_FLAG_NONE, 1025 var_psc_pregr_action)) < 0) 1026 msg_fatal("bad %s value: %s", VAR_PSC_PREGR_ACTION, 1027 var_psc_pregr_action); 1028 if ((psc_pipel_action = name_code(actions, NAME_CODE_FLAG_NONE, 1029 var_psc_pipel_action)) < 0) 1030 msg_fatal("bad %s value: %s", VAR_PSC_PIPEL_ACTION, 1031 var_psc_pipel_action); 1032 if ((psc_nsmtp_action = name_code(actions, NAME_CODE_FLAG_NONE, 1033 var_psc_nsmtp_action)) < 0) 1034 msg_fatal("bad %s value: %s", VAR_PSC_NSMTP_ACTION, 1035 var_psc_nsmtp_action); 1036 if ((psc_barlf_action = name_code(actions, NAME_CODE_FLAG_NONE, 1037 var_psc_barlf_action)) < 0) 1038 msg_fatal("bad %s value: %s", VAR_PSC_BARLF_ACTION, 1039 var_psc_barlf_action); 1040 /* Fail "closed" on error. */ 1041 psc_wlist_if = addr_match_list_init(VAR_PSC_WLIST_IF, MATCH_FLAG_RETURN, 1042 var_psc_wlist_if); 1043 1044 /* 1045 * Start the cache maintenance pseudo thread last. Early cleanup makes 1046 * verbose logging more informative (we get positive confirmation that 1047 * the cleanup thread runs). 1048 */ 1049 cache_flags = DICT_CACHE_FLAG_STATISTICS; 1050 if (msg_verbose > 1) 1051 cache_flags |= DICT_CACHE_FLAG_VERBOSE; 1052 if (psc_cache_map != 0 && var_psc_cache_scan > 0) 1053 dict_cache_control(psc_cache_map, 1054 CA_DICT_CACHE_CTL_FLAGS(cache_flags), 1055 CA_DICT_CACHE_CTL_INTERVAL(var_psc_cache_scan), 1056 CA_DICT_CACHE_CTL_VALIDATOR(psc_cache_validator), 1057 CA_DICT_CACHE_CTL_CONTEXT((void *) 0), 1058 CA_DICT_CACHE_CTL_END); 1059 1060 /* 1061 * Pre-compute the minimal and maximal TTL. 1062 */ 1063 psc_min_ttl = 1064 PSC_MIN(PSC_MIN(var_psc_pregr_ttl, var_psc_dnsbl_min_ttl), 1065 PSC_MIN(PSC_MIN(var_psc_pipel_ttl, var_psc_nsmtp_ttl), 1066 var_psc_barlf_ttl)); 1067 1068 /* 1069 * Pre-compute the stress and normal command time limits. 1070 */ 1071 mail_conf_update(VAR_STRESS, "yes"); 1072 psc_stress_cmd_time_limit = 1073 get_mail_conf_time(VAR_PSC_CMD_TIME, DEF_PSC_CMD_TIME, 1, 0); 1074 psc_stress_greet_wait = 1075 get_mail_conf_time(VAR_PSC_GREET_WAIT, DEF_PSC_GREET_WAIT, 1, 0); 1076 1077 mail_conf_update(VAR_STRESS, ""); 1078 psc_normal_cmd_time_limit = 1079 get_mail_conf_time(VAR_PSC_CMD_TIME, DEF_PSC_CMD_TIME, 1, 0); 1080 psc_normal_greet_wait = 1081 get_mail_conf_time(VAR_PSC_GREET_WAIT, DEF_PSC_GREET_WAIT, 1, 0); 1082 1083 psc_lowat_check_queue_length = .7 * var_psc_pre_queue_limit; 1084 psc_hiwat_check_queue_length = .9 * var_psc_pre_queue_limit; 1085 if (msg_verbose) 1086 msg_info(VAR_PSC_CMD_TIME ": stress=%d normal=%d lowat=%d hiwat=%d", 1087 psc_stress_cmd_time_limit, psc_normal_cmd_time_limit, 1088 psc_lowat_check_queue_length, psc_hiwat_check_queue_length); 1089 1090 if (psc_lowat_check_queue_length == 0) 1091 msg_panic("compiler error: 0.7 * %d = %d", var_psc_pre_queue_limit, 1092 psc_lowat_check_queue_length); 1093 if (psc_hiwat_check_queue_length == 0) 1094 msg_panic("compiler error: 0.9 * %d = %d", var_psc_pre_queue_limit, 1095 psc_hiwat_check_queue_length); 1096 1097 /* 1098 * Per-client concurrency. 1099 */ 1100 psc_client_concurrency = htable_create(var_psc_pre_queue_limit); 1101 } 1102 1103 MAIL_VERSION_STAMP_DECLARE; 1104 1105 /* main - pass control to the multi-threaded skeleton */ 1106 1107 int main(int argc, char **argv) 1108 { 1109 1110 /* 1111 * List smtpd(8) parameters before any postscreen(8) parameters that have 1112 * defaults dependencies on them. 1113 */ 1114 static const CONFIG_STR_TABLE str_table[] = { 1115 VAR_SMTPD_SERVICE, DEF_SMTPD_SERVICE, &var_smtpd_service, 1, 0, 1116 VAR_SMTPD_BANNER, DEF_SMTPD_BANNER, &var_smtpd_banner, 1, 0, 1117 VAR_SMTPD_FORBID_CMDS, DEF_SMTPD_FORBID_CMDS, &var_smtpd_forbid_cmds, 0, 0, 1118 VAR_SMTPD_EHLO_DIS_WORDS, DEF_SMTPD_EHLO_DIS_WORDS, &var_smtpd_ehlo_dis_words, 0, 0, 1119 VAR_SMTPD_EHLO_DIS_MAPS, DEF_SMTPD_EHLO_DIS_MAPS, &var_smtpd_ehlo_dis_maps, 0, 0, 1120 VAR_SMTPD_TLS_LEVEL, DEF_SMTPD_TLS_LEVEL, &var_smtpd_tls_level, 0, 0, 1121 VAR_SMTPD_CMD_FILTER, DEF_SMTPD_CMD_FILTER, &var_smtpd_cmd_filter, 0, 0, 1122 VAR_PSC_CACHE_MAP, DEF_PSC_CACHE_MAP, &var_psc_cache_map, 0, 0, 1123 VAR_PSC_PREGR_BANNER, DEF_PSC_PREGR_BANNER, &var_psc_pregr_banner, 0, 0, 1124 VAR_PSC_PREGR_ACTION, DEF_PSC_PREGR_ACTION, &var_psc_pregr_action, 1, 0, 1125 VAR_PSC_DNSBL_SITES, DEF_PSC_DNSBL_SITES, &var_psc_dnsbl_sites, 0, 0, 1126 VAR_PSC_DNSBL_ACTION, DEF_PSC_DNSBL_ACTION, &var_psc_dnsbl_action, 1, 0, 1127 VAR_PSC_PIPEL_ACTION, DEF_PSC_PIPEL_ACTION, &var_psc_pipel_action, 1, 0, 1128 VAR_PSC_NSMTP_ACTION, DEF_PSC_NSMTP_ACTION, &var_psc_nsmtp_action, 1, 0, 1129 VAR_PSC_BARLF_ACTION, DEF_PSC_BARLF_ACTION, &var_psc_barlf_action, 1, 0, 1130 VAR_PSC_ACL, DEF_PSC_ACL, &var_psc_acl, 0, 0, 1131 VAR_PSC_BLIST_ACTION, DEF_PSC_BLIST_ACTION, &var_psc_blist_action, 1, 0, 1132 VAR_PSC_FORBID_CMDS, DEF_PSC_FORBID_CMDS, &var_psc_forbid_cmds, 0, 0, 1133 VAR_PSC_EHLO_DIS_WORDS, DEF_PSC_EHLO_DIS_WORDS, &var_psc_ehlo_dis_words, 0, 0, 1134 VAR_PSC_EHLO_DIS_MAPS, DEF_PSC_EHLO_DIS_MAPS, &var_psc_ehlo_dis_maps, 0, 0, 1135 VAR_PSC_DNSBL_REPLY, DEF_PSC_DNSBL_REPLY, &var_psc_dnsbl_reply, 0, 0, 1136 VAR_PSC_TLS_LEVEL, DEF_PSC_TLS_LEVEL, &var_psc_tls_level, 0, 0, 1137 VAR_PSC_CMD_FILTER, DEF_PSC_CMD_FILTER, &var_psc_cmd_filter, 0, 0, 1138 VAR_DNSBLOG_SERVICE, DEF_DNSBLOG_SERVICE, &var_dnsblog_service, 1, 0, 1139 VAR_TLSPROXY_SERVICE, DEF_TLSPROXY_SERVICE, &var_tlsproxy_service, 1, 0, 1140 VAR_PSC_WLIST_IF, DEF_PSC_WLIST_IF, &var_psc_wlist_if, 0, 0, 1141 VAR_PSC_UPROXY_PROTO, DEF_PSC_UPROXY_PROTO, &var_psc_uproxy_proto, 0, 0, 1142 VAR_PSC_REJ_FTR_MAPS, DEF_PSC_REJ_FTR_MAPS, &var_psc_rej_ftr_maps, 0, 0, 1143 0, 1144 }; 1145 static const CONFIG_INT_TABLE int_table[] = { 1146 VAR_PSC_DNSBL_THRESH, DEF_PSC_DNSBL_THRESH, &var_psc_dnsbl_thresh, 0, 0, 1147 VAR_PSC_DNSBL_WTHRESH, DEF_PSC_DNSBL_WTHRESH, &var_psc_dnsbl_wthresh, 0, 0, 1148 VAR_PSC_CMD_COUNT, DEF_PSC_CMD_COUNT, &var_psc_cmd_count, 1, 0, 1149 VAR_SMTPD_CCONN_LIMIT, DEF_SMTPD_CCONN_LIMIT, &var_smtpd_cconn_limit, 0, 0, 1150 0, 1151 }; 1152 static const CONFIG_NINT_TABLE nint_table[] = { 1153 VAR_PSC_POST_QLIMIT, DEF_PSC_POST_QLIMIT, &var_psc_post_queue_limit, 5, 0, 1154 VAR_PSC_PRE_QLIMIT, DEF_PSC_PRE_QLIMIT, &var_psc_pre_queue_limit, 10, 0, 1155 VAR_PSC_CCONN_LIMIT, DEF_PSC_CCONN_LIMIT, &var_psc_cconn_limit, 0, 0, 1156 0, 1157 }; 1158 static const CONFIG_TIME_TABLE time_table[] = { 1159 VAR_PSC_CMD_TIME, DEF_PSC_CMD_TIME, &var_psc_cmd_time, 1, 0, 1160 VAR_PSC_GREET_WAIT, DEF_PSC_GREET_WAIT, &var_psc_greet_wait, 1, 0, 1161 VAR_PSC_PREGR_TTL, DEF_PSC_PREGR_TTL, &var_psc_pregr_ttl, 1, 0, 1162 VAR_PSC_DNSBL_MIN_TTL, DEF_PSC_DNSBL_MIN_TTL, &var_psc_dnsbl_min_ttl, 1, 0, 1163 VAR_PSC_DNSBL_MAX_TTL, DEF_PSC_DNSBL_MAX_TTL, &var_psc_dnsbl_max_ttl, 1, 0, 1164 VAR_PSC_PIPEL_TTL, DEF_PSC_PIPEL_TTL, &var_psc_pipel_ttl, 1, 0, 1165 VAR_PSC_NSMTP_TTL, DEF_PSC_NSMTP_TTL, &var_psc_nsmtp_ttl, 1, 0, 1166 VAR_PSC_BARLF_TTL, DEF_PSC_BARLF_TTL, &var_psc_barlf_ttl, 1, 0, 1167 VAR_PSC_CACHE_RET, DEF_PSC_CACHE_RET, &var_psc_cache_ret, 1, 0, 1168 VAR_PSC_CACHE_SCAN, DEF_PSC_CACHE_SCAN, &var_psc_cache_scan, 0, 0, 1169 VAR_PSC_WATCHDOG, DEF_PSC_WATCHDOG, &var_psc_watchdog, 10, 0, 1170 VAR_PSC_UPROXY_TMOUT, DEF_PSC_UPROXY_TMOUT, &var_psc_uproxy_tmout, 1, 0, 1171 VAR_PSC_DNSBL_TMOUT, DEF_PSC_DNSBL_TMOUT, &var_psc_dnsbl_tmout, 1, 0, 1172 1173 0, 1174 }; 1175 static const CONFIG_BOOL_TABLE bool_table[] = { 1176 VAR_HELO_REQUIRED, DEF_HELO_REQUIRED, &var_helo_required, 1177 VAR_DISABLE_VRFY_CMD, DEF_DISABLE_VRFY_CMD, &var_disable_vrfy_cmd, 1178 VAR_SMTPD_USE_TLS, DEF_SMTPD_USE_TLS, &var_smtpd_use_tls, 1179 VAR_SMTPD_ENFORCE_TLS, DEF_SMTPD_ENFORCE_TLS, &var_smtpd_enforce_tls, 1180 VAR_PSC_PIPEL_ENABLE, DEF_PSC_PIPEL_ENABLE, &var_psc_pipel_enable, 1181 VAR_PSC_NSMTP_ENABLE, DEF_PSC_NSMTP_ENABLE, &var_psc_nsmtp_enable, 1182 VAR_PSC_BARLF_ENABLE, DEF_PSC_BARLF_ENABLE, &var_psc_barlf_enable, 1183 0, 1184 }; 1185 static const CONFIG_RAW_TABLE raw_table[] = { 1186 VAR_SMTPD_REJ_FOOTER, DEF_SMTPD_REJ_FOOTER, &var_smtpd_rej_footer, 0, 0, 1187 VAR_PSC_REJ_FOOTER, DEF_PSC_REJ_FOOTER, &var_psc_rej_footer, 0, 0, 1188 VAR_SMTPD_EXP_FILTER, DEF_SMTPD_EXP_FILTER, &var_smtpd_exp_filter, 1, 0, 1189 VAR_PSC_EXP_FILTER, DEF_PSC_EXP_FILTER, &var_psc_exp_filter, 1, 0, 1190 0, 1191 }; 1192 static const CONFIG_NBOOL_TABLE nbool_table[] = { 1193 VAR_PSC_HELO_REQUIRED, DEF_PSC_HELO_REQUIRED, &var_psc_helo_required, 1194 VAR_PSC_DISABLE_VRFY, DEF_PSC_DISABLE_VRFY, &var_psc_disable_vrfy, 1195 VAR_PSC_USE_TLS, DEF_PSC_USE_TLS, &var_psc_use_tls, 1196 VAR_PSC_ENFORCE_TLS, DEF_PSC_ENFORCE_TLS, &var_psc_enforce_tls, 1197 0, 1198 }; 1199 1200 /* 1201 * Fingerprint executables and core dumps. 1202 */ 1203 MAIL_VERSION_STAMP_ALLOCATE; 1204 1205 event_server_main(argc, argv, psc_service, 1206 CA_MAIL_SERVER_STR_TABLE(str_table), 1207 CA_MAIL_SERVER_INT_TABLE(int_table), 1208 CA_MAIL_SERVER_NINT_TABLE(nint_table), 1209 CA_MAIL_SERVER_TIME_TABLE(time_table), 1210 CA_MAIL_SERVER_BOOL_TABLE(bool_table), 1211 CA_MAIL_SERVER_RAW_TABLE(raw_table), 1212 CA_MAIL_SERVER_NBOOL_TABLE(nbool_table), 1213 CA_MAIL_SERVER_PRE_INIT(pre_jail_init), 1214 CA_MAIL_SERVER_POST_INIT(post_jail_init), 1215 CA_MAIL_SERVER_PRE_ACCEPT(pre_accept), 1216 CA_MAIL_SERVER_SOLITARY, 1217 CA_MAIL_SERVER_SLOW_EXIT(psc_drain), 1218 CA_MAIL_SERVER_EXIT(psc_dump), 1219 CA_MAIL_SERVER_WATCHDOG(&var_psc_watchdog), 1220 0); 1221 } 1222