Mercurial > dnsbl
annotate src/dnsbl.cpp @ 190:004b855c6c1f
fix null pointer dereference from missing HELO command
| author | carl |
|---|---|
| date | Sat, 10 Nov 2007 10:52:50 -0800 |
| parents | edcefdb7ccc1 |
| children | 2a67d31099c3 |
| rev | line source |
|---|---|
| 94 | 1 /* |
| 2 | |
| 152 | 3 Copyright (c) 2007 Carl Byington - 510 Software Group, released under |
| 4 the GPL version 3 or any later version at your choice available at | |
| 5 http://www.gnu.org/licenses/gpl-3.0.txt | |
| 94 | 6 |
| 7 Based on a sample milter Copyright (c) 2000-2003 Sendmail, Inc. and its | |
| 8 suppliers. Inspired by the DCC by Rhyolite Software | |
| 9 | |
| 177 | 10 -b port The port used to talk to the dcc interface daemon |
| 94 | 11 -r port The port used to talk to our internal dns resolver processes |
| 12 -p port The port through which the MTA will connect to this milter. | |
| 13 -t sec The timeout value. | |
| 14 -c Check the config, and print a copy to stdout. Don't start the | |
| 15 milter or do anything with the socket. | |
| 16 -s Stress test by loading and deleting the current config in a loop. | |
| 163 | 17 -d level set the debug level |
| 94 | 18 -e f|t Print the results of looking up from address f and to address |
| 19 t in the current config | |
| 20 | |
| 21 */ | |
| 22 | |
| 23 | |
| 24 // from sendmail sample | |
| 25 #include <sys/types.h> | |
| 26 #include <sys/stat.h> | |
| 27 #include <errno.h> | |
| 28 #include <sysexits.h> | |
| 29 #include <unistd.h> | |
| 30 | |
| 31 // needed for socket io | |
| 32 #include <sys/ioctl.h> | |
| 33 #include <net/if.h> | |
| 34 #include <arpa/inet.h> | |
| 35 #include <netinet/in.h> | |
| 36 #include <netinet/tcp.h> | |
| 37 #include <netdb.h> | |
| 38 #include <sys/socket.h> | |
| 39 #include <sys/un.h> | |
| 40 | |
| 41 // needed for thread | |
| 42 #include <pthread.h> | |
| 43 | |
| 44 // needed for std c++ collections | |
| 45 #include <set> | |
| 46 #include <map> | |
| 47 #include <list> | |
| 48 | |
| 49 // for the dns resolver | |
| 50 #include <netinet/in.h> | |
| 51 #include <arpa/nameser.h> | |
| 52 #include <resolv.h> | |
| 53 | |
| 54 // misc stuff needed here | |
| 55 #include <ctype.h> | |
| 56 #include <syslog.h> | |
| 57 #include <pwd.h> | |
| 58 #include <sys/wait.h> /* header for waitpid() and various macros */ | |
| 59 #include <signal.h> /* header for signal functions */ | |
| 60 | |
| 61 #include "includes.h" | |
| 62 | |
| 63 static char* dnsbl_version="$Id$"; | |
| 64 | |
| 65 extern "C" { | |
| 66 sfsistat mlfi_connect(SMFICTX *ctx, char *hostname, _SOCK_ADDR *hostaddr); | |
| 163 | 67 sfsistat mlfi_helo(SMFICTX * ctx, char *helohost); |
| 94 | 68 sfsistat mlfi_envfrom(SMFICTX *ctx, char **argv); |
| 69 sfsistat mlfi_envrcpt(SMFICTX *ctx, char **argv); | |
| 163 | 70 sfsistat mlfi_header(SMFICTX* ctx, char* headerf, char* headerv); |
| 94 | 71 sfsistat mlfi_body(SMFICTX *ctx, u_char *data, size_t len); |
| 72 sfsistat mlfi_eom(SMFICTX *ctx); | |
| 73 sfsistat mlfi_abort(SMFICTX *ctx); | |
| 74 sfsistat mlfi_close(SMFICTX *ctx); | |
| 75 void sig_chld(int signo); | |
| 76 } | |
| 77 | |
| 78 int debug_syslog = 0; | |
| 79 bool syslog_opened = false; | |
| 80 bool use_syslog = true; // false to printf | |
| 81 bool loader_run = true; // used to stop the config loader thread | |
| 82 CONFIG *config = NULL; // protected by the config_mutex | |
| 83 int generation = 0; // protected by the config_mutex | |
| 84 const int maxlen = 1000; // used for snprintf buffers | |
| 85 | |
| 86 pthread_mutex_t config_mutex; | |
| 87 pthread_mutex_t syslog_mutex; | |
| 88 pthread_mutex_t resolve_mutex; | |
| 89 pthread_mutex_t fd_pool_mutex; | |
| 136 | 90 pthread_mutex_t rate_mutex; |
| 94 | 91 |
| 92 std::set<int> fd_pool; | |
| 136 | 93 int NULL_SOCKET = -1; |
| 94 const time_t ERROR_SOCKET_TIME = 60; // number of seconds between attempts to open a socket to the dns resolver process | |
| 95 char *resolver_port = NULL; // unix domain socket to talk to the dns resolver process | |
| 96 int resolver_socket = NULL_SOCKET; // socket used to listen for resolver requests | |
| 177 | 97 char *dccifd_port = NULL; // unix domain socket to talk to the dcc interface daemon |
| 136 | 98 time_t last_error_time; |
| 99 int resolver_sock_count = 0; // protected with fd_pool_mutex | |
| 100 int resolver_pool_size = 0; // protected with fd_pool_mutex | |
| 101 rcpt_rates rcpt_counts; // protected with rate_mutex | |
| 94 | 102 |
| 103 | |
| 104 struct ns_map { | |
| 105 // all the strings are owned by the keys/values in the ns_host string map | |
| 106 string_map ns_host; // nameserver name -> host name that uses this name server | |
| 107 ns_mapper ns_ip; // nameserver name -> ip address of the name server | |
| 108 ~ns_map(); | |
| 109 void add(char *name, char *refer); | |
| 110 }; | |
| 111 | |
| 112 | |
| 113 ns_map::~ns_map() { | |
| 114 for (string_map::iterator i=ns_host.begin(); i!=ns_host.end(); i++) { | |
| 115 char *x = (*i).first; | |
| 116 char *y = (*i).second; | |
| 117 free(x); | |
| 118 free(y); | |
| 119 } | |
| 120 ns_ip.clear(); | |
| 121 ns_host.clear(); | |
| 122 } | |
| 123 | |
| 124 | |
| 125 void ns_map::add(char *name, char *refer) { | |
| 126 string_map::iterator i = ns_host.find(name); | |
| 127 if (i != ns_host.end()) return; | |
| 128 char *x = strdup(name); | |
| 129 char *y = strdup(refer); | |
| 130 ns_ip[x] = 0; | |
| 131 ns_host[x] = y; | |
| 132 | |
| 133 } | |
| 134 | |
| 135 // packed structure to allow a single socket write to dump the | |
| 136 // length and the following answer. The packing attribute is gcc specific. | |
| 137 struct glommer { | |
| 138 int length; | |
| 139 #ifdef NS_PACKETSZ | |
| 115 | 140 u_char answer[NS_PACKETSZ*4]; // with a resolver, we return resolver answers |
| 94 | 141 #else |
| 142 int answer; // without a resolver, we return a single ip4 address, 0 == no answer | |
| 143 #endif | |
| 144 } __attribute__ ((packed)); | |
| 145 | |
| 146 | |
| 147 //////////////////////////////////////////////// | |
| 136 | 148 // helper to manipulate recipient counts |
| 149 // | |
| 150 int incr_rcpt_count(char *user); | |
| 151 int incr_rcpt_count(char *user) { | |
| 152 pthread_mutex_lock(&rate_mutex); | |
| 153 rcpt_rates::iterator i = rcpt_counts.find(user); | |
| 138 | 154 int c = 1; |
| 155 if (i == rcpt_counts.end()) { | |
| 156 user = strdup(user); | |
| 157 rcpt_counts[user] = c; | |
| 158 } | |
| 159 else { | |
| 139 | 160 c = ++((*i).second); |
| 138 | 161 } |
| 136 | 162 pthread_mutex_unlock(&rate_mutex); |
| 163 return c; | |
| 164 } | |
| 165 | |
| 166 //////////////////////////////////////////////// | |
| 94 | 167 // helper to discard the strings held by a context_map |
| 168 // | |
| 169 void discard(context_map &cm); | |
| 170 void discard(context_map &cm) { | |
| 171 for (context_map::iterator i=cm.begin(); i!=cm.end(); i++) { | |
| 172 char *x = (*i).first; | |
| 173 free(x); | |
| 174 } | |
| 175 cm.clear(); | |
| 176 } | |
| 177 | |
| 178 | |
| 179 //////////////////////////////////////////////// | |
| 180 // helper to register a string in a context_map | |
| 181 // | |
| 182 void register_string(context_map &cm, char *name, CONTEXT *con); | |
| 183 void register_string(context_map &cm, char *name, CONTEXT *con) { | |
| 184 context_map::iterator i = cm.find(name); | |
| 185 if (i != cm.end()) return; | |
| 186 char *x = strdup(name); | |
| 187 cm[x] = con; | |
| 188 } | |
| 189 | |
| 190 | |
| 191 //////////////////////////////////////////////// | |
| 192 // disconnect the fd from the dns resolver process | |
| 193 // | |
| 194 void my_disconnect(int sock, bool decrement = true); | |
| 195 void my_disconnect(int sock, bool decrement) { | |
| 196 if (sock != NULL_SOCKET) { | |
| 197 if (decrement) { | |
| 198 pthread_mutex_lock(&fd_pool_mutex); | |
| 199 resolver_sock_count--; | |
| 200 pthread_mutex_unlock(&fd_pool_mutex); | |
| 201 } | |
| 202 shutdown(sock, SHUT_RDWR); | |
| 203 close(sock); | |
| 204 } | |
| 205 } | |
| 206 | |
| 207 | |
| 208 //////////////////////////////////////////////// | |
| 209 // return fd connected to the dns resolver process | |
| 210 // | |
| 211 int my_connect(); | |
| 212 int my_connect() { | |
| 213 // if we have had recent errors, don't even try to open the socket | |
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214 if ((time(NULL) - last_error_time) < ERROR_SOCKET_TIME) return NULL_SOCKET; |
| 94 | 215 |
| 216 // nothing recent, maybe this time it will work | |
| 217 int sock = NULL_SOCKET; | |
| 218 sockaddr_un server; | |
| 219 memset(&server, '\0', sizeof(server)); | |
| 220 server.sun_family = AF_UNIX; | |
| 221 strncpy(server.sun_path, resolver_port, sizeof(server.sun_path)-1); | |
| 222 sock = socket(AF_UNIX, SOCK_STREAM, 0); | |
| 223 if (sock != NULL_SOCKET) { | |
| 224 bool rc = (connect(sock, (sockaddr *)&server, sizeof(server)) == 0); | |
| 225 if (!rc) { | |
| 226 my_disconnect(sock, false); | |
| 227 sock = NULL_SOCKET; | |
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228 last_error_time = time(NULL); |
| 94 | 229 } |
| 230 } | |
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231 else last_error_time = time(NULL); |
| 94 | 232 if (sock != NULL_SOCKET) { |
| 233 pthread_mutex_lock(&fd_pool_mutex); | |
| 234 resolver_sock_count++; | |
| 235 pthread_mutex_unlock(&fd_pool_mutex); | |
| 236 } | |
| 237 return sock; | |
| 238 } | |
| 239 | |
| 240 | |
| 241 mlfiPriv::mlfiPriv() { | |
| 242 pthread_mutex_lock(&config_mutex); | |
| 243 pc = config; | |
| 244 pc->reference_count++; | |
| 245 pthread_mutex_unlock(&config_mutex); | |
| 246 get_fd(); | |
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247 ctx = NULL; |
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248 eom = false; |
| 94 | 249 ip = 0; |
| 163 | 250 helo = NULL; |
| 94 | 251 mailaddr = NULL; |
| 252 queueid = NULL; | |
| 136 | 253 authenticated = NULL; |
| 168 | 254 client_name = NULL; |
| 94 | 255 have_whites = false; |
| 256 only_whites = true; | |
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257 want_spamassassin = false; |
| 178 | 258 want_dccgrey = false; |
| 259 want_dccbulk = false; | |
| 260 content_context = NULL; | |
| 94 | 261 memory = NULL; |
| 262 scanner = NULL; | |
| 263 content_suffix = NULL; | |
| 264 content_message = NULL; | |
| 119 | 265 uribl_suffix = NULL; |
| 266 uribl_message = NULL; | |
| 94 | 267 content_host_ignore = NULL; |
| 178 | 268 assassin = NULL; |
| 269 dccifd = NULL; | |
| 94 | 270 } |
| 271 | |
| 272 mlfiPriv::~mlfiPriv() { | |
| 273 return_fd(); | |
| 274 pthread_mutex_lock(&config_mutex); | |
| 275 pc->reference_count--; | |
| 146 | 276 bool last = (!pc->reference_count) && (pc != config); |
| 94 | 277 pthread_mutex_unlock(&config_mutex); |
| 146 | 278 if (last) delete pc; // free this config, since we were the last reference to it |
| 163 | 279 if (helo) free(helo); |
| 94 | 280 reset(true); |
| 281 } | |
| 282 | |
| 283 void mlfiPriv::reset(bool final) { | |
| 136 | 284 if (mailaddr) free(mailaddr); |
| 285 if (queueid) free(queueid); | |
| 286 if (authenticated) free(authenticated); | |
| 168 | 287 if (client_name) free(client_name); |
| 94 | 288 discard(env_to); |
| 163 | 289 if (memory) delete memory; |
| 290 if (scanner) delete scanner; | |
| 291 if (assassin) delete assassin; | |
| 178 | 292 if (dccifd) delete dccifd; |
| 94 | 293 if (!final) { |
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294 ctx = NULL; |
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295 eom = false; |
| 94 | 296 mailaddr = NULL; |
| 297 queueid = NULL; | |
| 136 | 298 authenticated = NULL; |
| 168 | 299 client_name = NULL; |
| 94 | 300 have_whites = false; |
| 301 only_whites = true; | |
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302 want_spamassassin = false; |
| 178 | 303 want_dccgrey = false; |
| 304 want_dccbulk = false; | |
| 305 content_context = NULL; | |
| 94 | 306 memory = NULL; |
| 307 scanner = NULL; | |
| 308 content_suffix = NULL; | |
| 309 content_message = NULL; | |
| 119 | 310 uribl_suffix = NULL; |
| 311 uribl_message = NULL; | |
| 94 | 312 content_host_ignore = NULL; |
| 178 | 313 assassin = NULL; |
| 314 dccifd = NULL; | |
| 94 | 315 } |
| 316 } | |
| 317 | |
| 318 void mlfiPriv::get_fd() { | |
| 319 err = true; | |
| 320 fd = NULL_SOCKET; | |
| 321 int result = pthread_mutex_lock(&fd_pool_mutex); | |
| 322 if (!result) { | |
| 323 std::set<int>::iterator i; | |
| 324 i = fd_pool.begin(); | |
| 325 if (i != fd_pool.end()) { | |
| 326 // have at least one fd in the pool | |
| 327 err = false; | |
| 328 fd = *i; | |
| 329 fd_pool.erase(fd); | |
| 330 resolver_pool_size--; | |
| 331 pthread_mutex_unlock(&fd_pool_mutex); | |
| 332 } | |
| 333 else { | |
| 334 // pool is empty, get a new fd | |
| 335 pthread_mutex_unlock(&fd_pool_mutex); | |
| 336 fd = my_connect(); | |
| 337 err = (fd == NULL_SOCKET); | |
| 338 } | |
| 339 } | |
| 340 else { | |
| 341 // cannot lock the pool, just get a new fd | |
| 342 fd = my_connect(); | |
| 343 err = (fd == NULL_SOCKET); | |
| 344 } | |
| 345 } | |
| 346 | |
| 347 void mlfiPriv::return_fd() { | |
| 348 if (err) { | |
| 349 // this fd got a socket error, so close it, rather than returning it to the pool | |
| 350 my_disconnect(fd); | |
| 351 } | |
| 352 else { | |
| 353 int result = pthread_mutex_lock(&fd_pool_mutex); | |
| 354 if (!result) { | |
| 355 if ((resolver_sock_count > resolver_pool_size*5) || (resolver_pool_size < 5)) { | |
| 356 // return the fd to the pool | |
| 357 fd_pool.insert(fd); | |
| 358 resolver_pool_size++; | |
| 359 pthread_mutex_unlock(&fd_pool_mutex); | |
| 360 } | |
| 361 else { | |
| 362 // more than 20% of the open resolver sockets are in the pool, and the | |
| 363 // pool as at least 5 sockets. that is enough, so just close this one. | |
| 364 pthread_mutex_unlock(&fd_pool_mutex); | |
| 365 my_disconnect(fd); | |
| 366 } | |
| 367 } | |
| 368 else { | |
| 369 // could not lock the pool, so just close the fd | |
| 370 my_disconnect(fd); | |
| 371 } | |
| 372 } | |
| 373 } | |
| 374 | |
| 177 | 375 size_t mlfiPriv::my_write(const char *buf, size_t len) { |
| 94 | 376 if (err) return 0; |
| 177 | 377 size_t rs = 0; |
| 94 | 378 while (len) { |
| 177 | 379 size_t ws = write(fd, buf, len); |
| 94 | 380 if (ws > 0) { |
| 381 rs += ws; | |
| 382 len -= ws; | |
| 383 buf += ws; | |
| 384 } | |
| 385 else { | |
| 386 // peer closed the socket! | |
| 387 rs = 0; | |
| 388 err = true; | |
| 389 break; | |
| 390 } | |
| 391 } | |
| 392 return rs; | |
| 393 } | |
| 394 | |
| 177 | 395 size_t mlfiPriv::my_read(char *buf, size_t len) { |
| 94 | 396 if (err) return 0; |
| 177 | 397 size_t rs = 0; |
| 134 | 398 while (len) { |
| 177 | 399 size_t ws = read(fd, buf, len); |
| 94 | 400 if (ws > 0) { |
| 401 rs += ws; | |
| 402 len -= ws; | |
| 403 buf += ws; | |
| 404 } | |
| 405 else { | |
| 406 // peer closed the socket! | |
| 407 rs = 0; | |
| 408 err = true; | |
| 409 break; | |
| 410 } | |
| 411 } | |
| 412 return rs; | |
| 413 } | |
| 414 | |
| 415 void mlfiPriv::need_content_filter(char *rcpt, CONTEXT &con) { | |
| 416 register_string(env_to, rcpt, &con); | |
| 417 if (!memory) { | |
| 178 | 418 // first recipient that needs content filtering sets |
| 419 // some of the content filtering parameters | |
| 117 | 420 memory = new recorder(this, con.get_html_tags(), con.get_content_tlds(), con.get_content_cctlds()); |
| 94 | 421 scanner = new url_scanner(memory); |
| 422 content_suffix = con.get_content_suffix(); | |
| 423 content_message = con.get_content_message(); | |
| 119 | 424 uribl_suffix = con.get_uribl_suffix(); |
| 425 uribl_message = con.get_uribl_message(); | |
| 94 | 426 content_host_ignore = &con.get_content_host_ignore(); |
| 427 } | |
| 428 } | |
| 429 | |
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430 |
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431 mlfiPriv* fetch_priv_from_ctx(SMFICTX *ctx); |
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432 mlfiPriv* fetch_priv_from_ctx(SMFICTX *ctx) |
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433 { |
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434 mlfiPriv *priv = (struct mlfiPriv *)smfi_getpriv(ctx); |
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435 priv->ctx = ctx; |
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436 return priv; |
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437 } |
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438 #define MLFIPRIV fetch_priv_from_ctx(ctx) |
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439 |
| 94 | 440 |
| 441 | |
| 442 //////////////////////////////////////////////// | |
| 443 // syslog a message | |
| 444 // | |
| 445 void my_syslog(mlfiPriv *priv, char *text) { | |
| 446 char buf[maxlen]; | |
| 447 if (priv) { | |
| 448 snprintf(buf, sizeof(buf), "%s: %s", priv->queueid, text); | |
| 449 text = buf; | |
| 450 } | |
| 451 if (use_syslog) { | |
| 452 pthread_mutex_lock(&syslog_mutex); | |
| 453 if (!syslog_opened) { | |
| 454 openlog("dnsbl", LOG_PID, LOG_MAIL); | |
| 455 syslog_opened = true; | |
| 456 } | |
| 457 syslog(LOG_NOTICE, "%s", text); | |
| 458 pthread_mutex_unlock(&syslog_mutex); | |
| 459 } | |
| 460 else { | |
| 461 printf("%s \n", text); | |
| 462 } | |
| 463 } | |
| 464 | |
| 163 | 465 void my_syslog(mlfiPriv *priv, string text) { |
| 466 if (debug_syslog > 3) { | |
| 467 char buf[maxlen]; | |
| 468 strncpy(buf, text.c_str(), sizeof(buf)); | |
| 469 buf[maxlen-1] = '\0'; // ensure null termination | |
| 470 my_syslog(priv, buf); | |
| 471 } | |
| 472 } | |
| 473 | |
| 94 | 474 void my_syslog(char *text) { |
| 475 my_syslog(NULL, text); | |
| 476 } | |
| 477 | |
| 478 | |
| 479 //////////////////////////////////////////////// | |
| 480 // read a resolver request from the socket, process it, and | |
| 481 // write the result back to the socket. | |
| 482 | |
| 483 void process_resolver_requests(int socket); | |
| 484 void process_resolver_requests(int socket) { | |
| 485 #ifdef NS_MAXDNAME | |
| 486 char question[NS_MAXDNAME]; | |
| 487 #else | |
| 488 char question[1000]; | |
| 489 #endif | |
| 490 glommer glom; | |
| 491 | |
| 492 int maxq = sizeof(question); | |
| 493 while (true) { | |
| 494 // read a question | |
| 495 int rs = 0; | |
| 496 while (rs < maxq) { | |
| 497 int ns = read(socket, question+rs, maxq-rs); | |
| 498 if (ns > 0) { | |
| 499 rs += ns; | |
| 500 if (question[rs-1] == '\0') { | |
| 501 // last byte read was the null terminator, we are done | |
| 502 break; | |
| 503 } | |
| 504 } | |
| 505 else { | |
| 506 // peer closed the socket | |
| 507 #ifdef RESOLVER_DEBUG | |
| 508 my_syslog("process_resolver_requests() peer closed socket while reading question"); | |
| 509 #endif | |
| 510 shutdown(socket, SHUT_RDWR); | |
| 511 close(socket); | |
| 512 return; | |
| 513 } | |
| 514 } | |
| 515 question[rs-1] = '\0'; // ensure null termination | |
| 516 | |
| 517 // find the answer | |
| 518 #ifdef NS_PACKETSZ | |
| 519 #ifdef RESOLVER_DEBUG | |
| 520 char text[1000]; | |
| 521 snprintf(text, sizeof(text), "process_resolver_requests() has a question %s", question); | |
| 522 my_syslog(text); | |
| 523 #endif | |
| 150 | 524 if ((_res.options & RES_INIT) == 0) res_init(); |
| 525 _res.retry = 2; | |
| 526 _res.retrans = RES_TIMEOUT; | |
| 94 | 527 glom.length = res_search(question, ns_c_in, ns_t_a, glom.answer, sizeof(glom.answer)); |
| 528 if (glom.length < 0) glom.length = 0; // represent all errors as zero length answers | |
| 529 #else | |
| 530 glom.length = sizeof(glom.answer); | |
| 531 glom.answer = 0; | |
| 532 struct hostent *host = gethostbyname(question); | |
| 533 if (host && (host->h_addrtype == AF_INET)) { | |
| 534 memcpy(&glom.answer, host->h_addr, sizeof(glom.answer)); | |
| 535 } | |
| 536 #endif | |
| 537 | |
| 538 // write the answer | |
| 539 char *buf = (char *)&glom; | |
| 540 int len = glom.length + sizeof(glom.length); | |
| 541 #ifdef RESOLVER_DEBUG | |
| 542 snprintf(text, sizeof(text), "process_resolver_requests() writing answer length %d for total %d", glom.length, len); | |
| 543 my_syslog(text); | |
| 544 #endif | |
| 545 int ws = 0; | |
| 546 while (len > ws) { | |
| 547 int ns = write(socket, buf+ws, len-ws); | |
| 548 if (ns > 0) { | |
| 549 ws += ns; | |
| 550 } | |
| 551 else { | |
| 552 // peer closed the socket! | |
| 553 #ifdef RESOLVER_DEBUG | |
| 554 my_syslog("process_resolver_requests() peer closed socket while writing answer"); | |
| 555 #endif | |
| 556 shutdown(socket, SHUT_RDWR); | |
| 557 close(socket); | |
| 558 return; | |
| 559 } | |
| 560 } | |
| 561 } | |
| 562 } | |
| 563 | |
| 564 | |
| 565 //////////////////////////////////////////////// | |
| 566 // ask a dns question and get an A record answer - we don't try | |
| 567 // very hard, just using the default resolver retry settings. | |
| 568 // If we cannot get an answer, we just accept the mail. | |
| 569 // | |
| 570 // | |
| 571 int dns_interface(mlfiPriv &priv, char *question, bool maybe_ip, ns_map *nameservers); | |
| 572 int dns_interface(mlfiPriv &priv, char *question, bool maybe_ip, ns_map *nameservers) { | |
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573 // tell sendmail we are still working |
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574 #if _FFR_SMFI_PROGRESS |
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575 if (priv.eom) smfi_progress(priv.ctx); |
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576 #endif |
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577 |
| 94 | 578 // this part can be done without locking the resolver mutex. Each |
| 579 // milter thread is talking over its own socket to a separate resolver | |
| 580 // process, which does the actual dns resolution. | |
| 581 if (priv.err) return 0; // cannot ask more questions on this socket. | |
| 134 | 582 if (maybe_ip) { |
| 583 // might be a bare ip address, try this first to avoid dns lookups that may not be needed | |
| 584 in_addr ip; | |
| 585 if (inet_aton(question, &ip)) { | |
| 586 return (int)ip.s_addr; | |
| 587 } | |
| 588 } | |
| 589 int n = strlen(question); | |
| 590 if (question[n-1] == '.') { | |
| 591 priv.my_write(question, n+1); // write the question including the null terminator | |
| 592 } | |
| 593 else { | |
| 594 priv.my_write(question, n); // write the question | |
| 595 priv.my_write(".", 2); // and the fully qualified . terminator and null string terminator | |
| 596 } | |
| 94 | 597 glommer glom; |
| 598 char *buf = (char *)&glom; | |
| 599 priv.my_read(buf, sizeof(glom.length)); | |
| 600 buf += sizeof(glom.length); | |
| 601 #ifdef RESOLVER_DEBUG | |
| 602 char text[1000]; | |
| 603 snprintf(text, sizeof(text), "dns_interface() wrote question %s and has answer length %d", question, glom.length); | |
| 604 my_syslog(text); | |
| 605 #endif | |
| 606 if ((glom.length < 0) || (glom.length > sizeof(glom.answer))) { | |
| 607 priv.err = true; | |
| 608 return 0; // cannot process overlarge answers | |
| 609 } | |
| 610 priv.my_read(buf, glom.length); | |
| 611 | |
| 612 #ifdef NS_PACKETSZ | |
| 613 // now we need to lock the resolver mutex to keep the milter threads from | |
| 614 // stepping on each other while parsing the dns answer. | |
| 615 int ret_address = 0; | |
| 616 pthread_mutex_lock(&resolve_mutex); | |
| 617 if (glom.length > 0) { | |
| 618 // parse the answer | |
| 619 ns_msg handle; | |
| 620 ns_rr rr; | |
| 621 if (ns_initparse(glom.answer, glom.length, &handle) == 0) { | |
| 622 // look for ns names | |
| 623 if (nameservers) { | |
| 624 ns_map &ns = *nameservers; | |
| 625 int rrnum = 0; | |
| 626 while (ns_parserr(&handle, ns_s_ns, rrnum++, &rr) == 0) { | |
| 627 if (ns_rr_type(rr) == ns_t_ns) { | |
| 628 char nam[NS_MAXDNAME+1]; | |
| 629 char *n = nam; | |
| 630 const u_char *p = ns_rr_rdata(rr); | |
| 631 while (((n-nam) < NS_MAXDNAME) && ((p-glom.answer) < glom.length) && *p) { | |
| 632 size_t s = *(p++); | |
| 633 if (s > 191) { | |
| 634 // compression pointer | |
| 635 s = (s-192)*256 + *(p++); | |
| 636 if (s >= glom.length) break; // pointer outside bounds of answer | |
| 637 p = glom.answer + s; | |
| 638 s = *(p++); | |
| 639 } | |
| 640 if (s > 0) { | |
| 641 if ((n-nam) >= (NS_MAXDNAME-s)) break; // destination would overflow name buffer | |
| 642 if ((p-glom.answer) >= (glom.length-s)) break; // source outside bounds of answer | |
| 643 memcpy(n, p, s); | |
| 644 n += s; | |
| 645 p += s; | |
| 646 *(n++) = '.'; | |
| 647 } | |
| 648 } | |
| 649 if (n-nam) n--; // remove trailing . | |
| 650 *n = '\0'; // null terminate it | |
| 651 ns.add(nam, question); // ns host to lookup later | |
| 652 } | |
| 653 } | |
| 654 rrnum = 0; | |
| 655 while (ns_parserr(&handle, ns_s_ar, rrnum++, &rr) == 0) { | |
| 656 if (ns_rr_type(rr) == ns_t_a) { | |
| 657 char* nam = (char*)ns_rr_name(rr); | |
| 658 ns_mapper::iterator i = ns.ns_ip.find(nam); | |
| 659 if (i != ns.ns_ip.end()) { | |
| 660 // we want this ip address | |
| 661 int address; | |
| 662 memcpy(&address, ns_rr_rdata(rr), sizeof(address)); | |
| 663 ns.ns_ip[nam] = address; | |
| 664 } | |
| 665 } | |
| 666 } | |
| 667 } | |
| 668 int rrnum = 0; | |
| 669 while (ns_parserr(&handle, ns_s_an, rrnum++, &rr) == 0) { | |
| 670 if (ns_rr_type(rr) == ns_t_a) { | |
| 671 int address; | |
| 672 memcpy(&address, ns_rr_rdata(rr), sizeof(address)); | |
| 673 ret_address = address; | |
| 674 } | |
| 675 } | |
| 676 } | |
| 677 } | |
| 678 pthread_mutex_unlock(&resolve_mutex); | |
| 679 return ret_address; | |
| 680 #else | |
| 681 return glom.answer; | |
| 682 #endif | |
| 683 } | |
| 684 | |
| 685 | |
| 686 //////////////////////////////////////////////// | |
| 687 // check a single dnsbl | |
| 688 // | |
| 689 bool check_single(mlfiPriv &priv, int ip, char *suffix); | |
| 690 bool check_single(mlfiPriv &priv, int ip, char *suffix) { | |
| 691 // make a dns question | |
| 692 const u_char *src = (const u_char *)&ip; | |
| 693 if (src[0] == 127) return false; // don't do dns lookups on localhost | |
| 126 | 694 if (src[0] == 10) return false; // don't do dns lookups on rfc1918 space |
| 695 if ((src[0] == 192) && (src[1] == 168)) return false; | |
| 696 if ((src[0] == 172) && (16 <= src[1]) && (src[1] <= 31)) return false; | |
| 94 | 697 #ifdef NS_MAXDNAME |
| 698 char question[NS_MAXDNAME]; | |
| 699 #else | |
| 700 char question[1000]; | |
| 701 #endif | |
| 702 snprintf(question, sizeof(question), "%u.%u.%u.%u.%s.", src[3], src[2], src[1], src[0], suffix); | |
| 703 // ask the question, if we get an A record it implies a blacklisted ip address | |
| 704 return dns_interface(priv, question, false, NULL); | |
| 705 } | |
| 706 | |
| 707 | |
| 708 //////////////////////////////////////////////// | |
| 709 // check a single dnsbl | |
| 710 // | |
| 711 bool check_single(mlfiPriv &priv, int ip, DNSBL &bl); | |
| 712 bool check_single(mlfiPriv &priv, int ip, DNSBL &bl) { | |
| 713 return check_single(priv, ip, bl.suffix); | |
| 714 } | |
| 715 | |
| 716 | |
| 717 //////////////////////////////////////////////// | |
| 718 // check the dnsbls specified for this recipient | |
| 719 // | |
| 720 bool check_dnsbl(mlfiPriv &priv, dnsblp_list &dnsbll, DNSBLP &rejectlist); | |
| 721 bool check_dnsbl(mlfiPriv &priv, dnsblp_list &dnsbll, DNSBLP &rejectlist) { | |
| 722 for (dnsblp_list::iterator i=dnsbll.begin(); i!=dnsbll.end(); i++) { | |
| 723 DNSBLP dp = *i; // non null by construction | |
| 724 bool st; | |
| 725 map<DNSBLP, bool>::iterator f = priv.checked.find(dp); | |
| 726 if (f == priv.checked.end()) { | |
| 727 // have not checked this list yet | |
| 728 st = check_single(priv, priv.ip, *dp); | |
| 729 rejectlist = dp; | |
| 730 priv.checked[dp] = st; | |
| 731 } | |
| 732 else { | |
| 733 st = (*f).second; | |
| 734 rejectlist = (*f).first; | |
| 735 } | |
| 736 if (st) return st; | |
| 737 } | |
| 738 return false; | |
| 739 } | |
| 740 | |
| 741 | |
| 742 //////////////////////////////////////////////// | |
| 134 | 743 // lookup the domain name part of a hostname on the uribl |
| 117 | 744 // |
| 124 | 745 // if we find part of the hostname on the uribl, return |
| 178 | 746 // true and point found to the part of the hostname that we found |
| 747 // as a string registered in hosts. | |
| 124 | 748 // otherwise, return false and preserve the value of found. |
| 749 // | |
| 178 | 750 bool uriblookup(mlfiPriv &priv, string_set &hosts, char *hostname, char *top, char *&found) ; |
| 751 bool uriblookup(mlfiPriv &priv, string_set &hosts, char *hostname, char *top, char *&found) { | |
| 117 | 752 // top is pointer to '.' char at end of base domain, or null for ip address form |
| 753 // so for hostname of www.fred.mydomain.co.uk | |
| 754 // top points to-----------------------^ | |
| 755 // and we end up looking at only mydomain.co.uk, ignoring the www.fred stuff | |
| 756 char buf[maxlen]; | |
| 757 if (top) { | |
| 758 // add one more component | |
| 759 *top = '\0'; | |
| 760 char *x = strrchr(hostname, '.'); | |
| 761 if (x) hostname = x+1; | |
| 762 *top = '.'; | |
| 763 } | |
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764 snprintf(buf, sizeof(buf), "%s.%s.", hostname, priv.uribl_suffix); |
| 119 | 765 if (dns_interface(priv, buf, false, NULL)) { |
| 117 | 766 if (debug_syslog > 2) { |
| 767 char tmp[maxlen]; | |
| 119 | 768 snprintf(tmp, sizeof(tmp), "found %s on %s", hostname, priv.uribl_suffix); |
| 117 | 769 my_syslog(tmp); |
| 770 } | |
| 178 | 771 found = register_string(hosts, hostname); |
| 119 | 772 return true; |
| 117 | 773 } |
| 774 return false; | |
| 775 } | |
| 776 | |
| 777 | |
| 778 //////////////////////////////////////////////// | |
| 124 | 779 // uribl checker |
| 780 // ------------- | |
| 781 // hostname MUST not have a trailing dot | |
| 782 // If tld, two level lookup. | |
| 783 // Else, look up three level domain. | |
| 784 // | |
| 785 // if we find part of the hostname on the uribl, return | |
| 178 | 786 // true and point found to the part of the hostname that we found |
| 787 // as a string registered in hosts. | |
| 124 | 788 // otherwise, return false and preserve the value of found. |
| 789 // | |
| 178 | 790 bool check_uribl(mlfiPriv &priv, string_set &hosts, char *hostname, char *&found) ; |
| 791 bool check_uribl(mlfiPriv &priv, string_set &hosts, char *hostname, char *&found) { | |
| 117 | 792 in_addr ip; |
| 793 if (inet_aton(hostname, &ip)) { | |
| 120 | 794 const u_char *src = (const u_char *)&ip.s_addr; |
| 128 | 795 if (src[0] == 127) return false; // don't do dns lookups on localhost |
| 796 if (src[0] == 10) return false; // don't do dns lookups on rfc1918 space | |
| 797 if ((src[0] == 192) && (src[1] == 168)) return false; | |
| 798 if ((src[0] == 172) && (16 <= src[1]) && (src[1] <= 31)) return false; | |
| 178 | 799 char adr[sizeof "255.255.255.255 "]; |
| 120 | 800 snprintf(adr, sizeof(adr), "%u.%u.%u.%u", src[3], src[2], src[1], src[0]); |
| 179 | 801 // cannot use inet_ntop here since we want the octets reversed. |
| 178 | 802 return (uriblookup(priv, hosts, adr, NULL, found)); |
| 117 | 803 } |
| 804 | |
| 805 char *top, *top2, *top3; | |
| 806 top = strrchr(hostname, '.'); | |
| 807 if (top) { | |
| 808 *top = '\0'; | |
| 809 top2 = strrchr(hostname, '.'); | |
| 810 *top = '.'; | |
| 811 | |
| 812 if (top2) { | |
| 813 string_set::iterator i = priv.memory->get_cctlds()->find(top2+1); | |
| 814 string_set::iterator x = priv.memory->get_cctlds()->end(); | |
| 815 // if we have a 2-level-cctld, just look at top three levels of the name | |
| 178 | 816 if (i != x) return uriblookup(priv, hosts, hostname, top2, found); |
| 117 | 817 |
| 818 *top2 = '\0'; | |
| 819 top3 = strrchr(hostname, '.'); | |
| 820 *top2 = '.'; | |
| 821 | |
| 822 // if we have more than 3 levels in the name, look at the top three levels of the name | |
| 178 | 823 if (top3 && uriblookup(priv, hosts, hostname, top2, found)) return true; |
| 117 | 824 // if that was not found, fall thru to looking at the top two levels |
| 825 } | |
| 826 // look at the top two levels of the name | |
| 178 | 827 return uriblookup(priv, hosts, hostname, top, found); |
| 117 | 828 } |
| 829 return false; | |
| 830 } | |
| 831 | |
| 832 | |
| 833 //////////////////////////////////////////////// | |
| 119 | 834 // check the hosts from the body against the content filter and uribl dnsbls |
| 94 | 835 // |
| 124 | 836 // |
| 837 bool check_hosts(mlfiPriv &priv, bool random, int limit, char *&msg, char *&host, int &ip, char *&found); | |
| 838 bool check_hosts(mlfiPriv &priv, bool random, int limit, char *&msg, char *&host, int &ip, char *&found) { | |
| 839 found = NULL; // normally ip address style | |
| 119 | 840 if (!priv.content_suffix && !priv.uribl_suffix) return false; // nothing to check |
| 94 | 841 CONFIG &dc = *priv.pc; |
| 842 string_set &hosts = priv.memory->get_hosts(); | |
| 843 string_set &ignore = *priv.content_host_ignore; | |
| 844 | |
| 845 int count = 0; | |
| 846 int cnt = hosts.size(); // number of hosts we could look at | |
| 847 int_set ips; | |
| 848 ns_map nameservers; | |
| 849 for (string_set::iterator i=hosts.begin(); i!=hosts.end(); i++) { | |
| 850 host = *i; // a reference into hosts, which will live until this smtp transaction is closed | |
| 851 | |
| 852 // don't bother looking up hosts on the ignore list | |
| 853 string_set::iterator j = ignore.find(host); | |
| 854 if (j != ignore.end()) continue; | |
| 855 | |
| 856 // try to only look at limit/cnt fraction of the available cnt host names in random mode | |
| 857 if ((cnt > limit) && (limit > 0) && random) { | |
| 858 int r = rand() % cnt; | |
| 859 if (r >= limit) { | |
| 860 if (debug_syslog > 2) { | |
| 861 char buf[maxlen]; | |
| 862 snprintf(buf, sizeof(buf), "host %s skipped", host); | |
| 863 my_syslog(&priv, buf); | |
| 864 } | |
| 865 continue; | |
| 866 } | |
| 867 } | |
| 868 count++; | |
| 869 ip = dns_interface(priv, host, true, &nameservers); | |
| 870 if (debug_syslog > 2) { | |
| 871 char buf[maxlen]; | |
| 872 if (ip) { | |
| 178 | 873 char adr[sizeof "255.255.255.255 "]; |
| 94 | 874 adr[0] = '\0'; |
| 875 inet_ntop(AF_INET, (const u_char *)&ip, adr, sizeof(adr)); | |
| 876 snprintf(buf, sizeof(buf), "host %s found at %s", host, adr); | |
| 877 } | |
| 878 else { | |
| 879 snprintf(buf, sizeof(buf), "host %s not found", host); | |
| 880 } | |
| 881 my_syslog(&priv, buf); | |
| 882 } | |
| 883 if (ip) { | |
| 884 int_set::iterator i = ips.find(ip); | |
| 885 if (i == ips.end()) { | |
| 117 | 886 // we haven't looked this up yet |
| 94 | 887 ips.insert(ip); |
| 124 | 888 // check dnsbl style list |
| 889 if (priv.content_suffix && check_single(priv, ip, priv.content_suffix)) { | |
| 119 | 890 msg = priv.content_message; |
| 891 return true; | |
| 892 } | |
| 124 | 893 // Check uribl & surbl style list |
| 178 | 894 if (priv.uribl_suffix && check_uribl(priv, hosts, host, found)) { |
| 119 | 895 msg = priv.uribl_message; |
| 896 return true; | |
| 897 } | |
| 94 | 898 } |
| 899 } | |
| 900 } | |
| 901 limit *= 4; // allow average of 3 ns per host name | |
| 902 for (ns_mapper::iterator i=nameservers.ns_ip.begin(); i!=nameservers.ns_ip.end(); i++) { | |
| 903 count++; | |
| 119 | 904 if ((count > limit) && (limit > 0)) return false; // too many name servers to check them all |
| 94 | 905 host = (*i).first; // a transient reference that needs to be replaced before we return it |
| 906 ip = (*i).second; | |
| 907 if (!ip) ip = dns_interface(priv, host, false, NULL); | |
| 908 if (debug_syslog > 2) { | |
| 909 char buf[maxlen]; | |
| 910 if (ip) { | |
| 178 | 911 char adr[sizeof "255.255.255.255 "]; |
| 94 | 912 adr[0] = '\0'; |
| 913 inet_ntop(AF_INET, (const u_char *)&ip, adr, sizeof(adr)); | |
| 914 snprintf(buf, sizeof(buf), "ns %s found at %s", host, adr); | |
| 915 } | |
| 916 else { | |
| 917 snprintf(buf, sizeof(buf), "ns %s not found", host); | |
| 918 } | |
| 919 my_syslog(&priv, buf); | |
| 920 } | |
| 921 if (ip) { | |
| 922 int_set::iterator i = ips.find(ip); | |
| 923 if (i == ips.end()) { | |
| 924 ips.insert(ip); | |
| 119 | 925 if (check_single(priv, ip, priv.content_suffix)) { |
| 926 msg = priv.content_message; | |
| 94 | 927 string_map::iterator j = nameservers.ns_host.find(host); |
| 928 if (j != nameservers.ns_host.end()) { | |
| 929 char *refer = (*j).second; | |
| 930 char buf[maxlen]; | |
| 931 snprintf(buf, sizeof(buf), "%s with nameserver %s", refer, host); | |
| 932 host = register_string(hosts, buf); // put a copy into hosts, and return that reference | |
| 933 } | |
| 934 else { | |
| 935 host = register_string(hosts, host); // put a copy into hosts, and return that reference | |
| 936 } | |
| 937 return true; | |
| 938 } | |
| 939 } | |
| 940 } | |
| 941 } | |
| 942 return false; | |
| 943 } | |
| 944 | |
| 127 | 945 |
| 94 | 946 //////////////////////////////////////////////// |
| 127 | 947 // |
| 948 // this email address is passed in from sendmail, and will normally be | |
| 949 // enclosed in <>. I think older versions of sendmail supplied the <> | |
| 950 // wrapper if the mail client did not, but the current version does not do | |
| 951 // that. So the <> wrapper is now optional. It may have mixed case, just | |
| 952 // as the mail client sent it. We dup the string and convert the duplicate | |
| 953 // to lower case. | |
| 94 | 954 // |
| 955 char *to_lower_string(char *email); | |
| 956 char *to_lower_string(char *email) { | |
| 127 | 957 int n = strlen(email); |
| 958 if (*email == '<') { | |
| 959 // assume it also ends with > | |
| 960 n -= 2; | |
| 961 if (n < 1) return strdup(email); // return "<>" | |
| 962 email++; | |
| 963 } | |
| 964 char *key = strdup(email); | |
| 94 | 965 key[n] = '\0'; |
| 966 for (int i=0; i<n; i++) key[i] = tolower(key[i]); | |
| 967 return key; | |
| 968 } | |
| 969 | |
| 970 | |
| 971 //////////////////////////////////////////////// | |
| 972 // start of sendmail milter interfaces | |
| 973 // | |
| 974 sfsistat mlfi_connect(SMFICTX *ctx, char *hostname, _SOCK_ADDR *hostaddr) | |
| 975 { | |
| 976 // allocate some private memory | |
| 977 mlfiPriv *priv = new mlfiPriv; | |
| 978 if (hostaddr->sa_family == AF_INET) { | |
| 979 priv->ip = ((struct sockaddr_in *)hostaddr)->sin_addr.s_addr; | |
| 980 } | |
| 981 // save the private data | |
| 982 smfi_setpriv(ctx, (void*)priv); | |
| 983 | |
| 984 // continue processing | |
| 985 return SMFIS_CONTINUE; | |
| 986 } | |
| 987 | |
| 163 | 988 sfsistat mlfi_helo(SMFICTX * ctx, char *helohost) |
| 989 { | |
| 990 mlfiPriv &priv = *MLFIPRIV; | |
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991 priv.helo = (helohost) ? strdup(helohost) : strdup("missing"); |
| 163 | 992 return SMFIS_CONTINUE; |
| 993 } | |
| 994 | |
| 94 | 995 sfsistat mlfi_envfrom(SMFICTX *ctx, char **from) |
| 996 { | |
| 997 mlfiPriv &priv = *MLFIPRIV; | |
| 998 priv.mailaddr = to_lower_string(from[0]); | |
| 163 | 999 priv.queueid = strdup(smfi_getsymval(ctx, "i")); |
| 136 | 1000 priv.authenticated = smfi_getsymval(ctx, "{auth_authen}"); |
| 168 | 1001 priv.client_name = smfi_getsymval(ctx, "_"); |
| 136 | 1002 if (priv.authenticated) priv.authenticated = strdup(priv.authenticated); |
| 168 | 1003 if (priv.client_name) priv.client_name = strdup(priv.client_name); |
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1004 if (spamc != spamc_empty) { |
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1005 priv.assassin = new SpamAssassin(&priv, priv.ip, priv.helo, priv.mailaddr, priv.queueid); |
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1006 } |
| 178 | 1007 if (dccifd_port) { |
| 179 | 1008 priv.dccifd = new DccInterface(dccifd_port, &priv, priv.ip, priv.helo, priv.mailaddr); |
| 178 | 1009 } |
| 94 | 1010 return SMFIS_CONTINUE; |
| 1011 } | |
| 1012 | |
| 1013 sfsistat mlfi_envrcpt(SMFICTX *ctx, char **rcpt) | |
| 1014 { | |
| 1015 DNSBLP rejectlist = NULL; // list that caused the reject | |
| 1016 mlfiPriv &priv = *MLFIPRIV; | |
| 1017 CONFIG &dc = *priv.pc; | |
| 152 | 1018 char *rcptaddr = rcpt[0]; |
| 1019 char *loto = to_lower_string(rcptaddr); | |
| 174 | 1020 |
| 1021 // some version of sendmail allowed rcpt to:<> and passed it thru to the milters | |
| 1022 if (strcmp(loto, "<>") == 0) { | |
| 1023 smfi_setreply(ctx, "550", "5.7.1", "bogus recipient"); | |
| 1024 return SMFIS_REJECT; | |
| 1025 } | |
| 152 | 1026 // priv.mailaddr sending original message to loto |
| 1027 CONTEXT &con = *(dc.find_context(loto)->find_context(priv.mailaddr)); | |
| 1028 VERIFYP ver = con.find_verify(loto); | |
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1029 char *fromvalue = con.find_from(priv.mailaddr, true); |
| 179 | 1030 // tell spam assassin and dccifd about this recipient |
| 1031 if (priv.assassin) priv.assassin->mlfi_envrcpt(ctx, loto); | |
| 182 | 1032 if (priv.dccifd) priv.dccifd->mlfi_envrcpt(ctx, loto, con.get_grey() && !priv.authenticated); |
| 152 | 1033 // loto sending a reply back to priv.mailaddr |
| 1034 CONTEXT &con2 = *(dc.find_context(priv.mailaddr)->find_context(loto)); | |
| 1035 char *replyvalue = con2.find_from(loto); | |
| 94 | 1036 if (debug_syslog > 1) { |
| 1037 char buf[maxlen]; | |
| 1038 char msg[maxlen]; | |
| 156 | 1039 snprintf(msg, sizeof(msg), "from <%s> to <%s> using context %s state %s reply state %s", priv.mailaddr, loto, con.get_full_name(buf,maxlen), fromvalue, replyvalue); |
| 94 | 1040 my_syslog(&priv, msg); |
| 1041 } | |
| 1042 free(loto); | |
| 1043 status st; | |
| 152 | 1044 if (replyvalue == token_black) { |
| 1045 smfi_setreply(ctx, "550", "5.7.1", "recipient can not reply due to blacklisting"); | |
| 1046 return SMFIS_REJECT; | |
| 1047 } | |
| 94 | 1048 if (priv.authenticated) { |
| 136 | 1049 int c = incr_rcpt_count(priv.authenticated); |
| 1050 int l = dc.default_context->find_rate(priv.authenticated); | |
| 142 | 1051 if (debug_syslog > 1) { |
| 1052 char buf[maxlen]; | |
| 1053 char msg[maxlen]; | |
| 1054 snprintf(msg, sizeof(msg), "authenticated id %s (%d recipients, %d limit)", priv.authenticated, c, l); | |
| 1055 my_syslog(&priv, msg); | |
| 1056 } | |
| 136 | 1057 if (c > l) { |
| 1058 smfi_setreply(ctx, "550", "5.7.1", "recipient rate limit exceeded"); | |
| 1059 return SMFIS_REJECT; | |
| 1060 } | |
| 142 | 1061 st = white; |
| 94 | 1062 } |
| 1063 else if (fromvalue == token_black) { | |
| 1064 st = black; | |
| 1065 } | |
| 1066 else if (fromvalue == token_white) { | |
| 1067 st = white; | |
| 1068 } | |
| 1069 else { | |
| 1070 // check the dns based lists | |
| 1071 st = (check_dnsbl(priv, con.get_dnsbl_list(), rejectlist)) ? reject : oksofar; | |
| 1072 } | |
| 1073 if (st == reject) { | |
| 1074 // reject the recipient based on some dnsbl | |
| 178 | 1075 char adr[sizeof "255.255.255.255 "]; |
| 94 | 1076 adr[0] = '\0'; |
| 1077 inet_ntop(AF_INET, (const u_char *)&priv.ip, adr, sizeof(adr)); | |
| 1078 char buf[maxlen]; | |
| 1079 snprintf(buf, sizeof(buf), rejectlist->message, adr, adr); | |
| 1080 smfi_setreply(ctx, "550", "5.7.1", buf); | |
| 1081 return SMFIS_REJECT; | |
| 1082 } | |
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1083 if (st == oksofar) { |
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1084 char *msg = con.generic_match(priv.client_name); |
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1085 if (msg) { |
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1086 // reject the recipient based on generic reverse dns |
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1087 char buf[maxlen]; |
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1088 snprintf(buf, sizeof(buf), msg, priv.client_name); |
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1089 smfi_setreply(ctx, "550", "5.7.1", buf); |
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1090 return SMFIS_REJECT; |
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1091 } |
| 168 | 1092 } |
| 94 | 1093 if (st == black) { |
| 1094 // reject the recipient based on blacklisting either from or to | |
| 1095 smfi_setreply(ctx, "550", "5.7.1", "no such user"); | |
| 1096 return SMFIS_REJECT; | |
| 1097 } | |
| 1098 if (ver && (st != white)) { | |
| 1099 // try to verify this from/to pair of addresses since it is not explicitly whitelisted | |
| 1100 char *loto = to_lower_string(rcptaddr); | |
| 1101 bool rc = ver->ok(priv.mailaddr, loto); | |
| 1102 free(loto); | |
| 1103 if (!rc) { | |
| 1104 smfi_setreply(ctx, "550", "5.7.1", "no such user"); | |
| 1105 return SMFIS_REJECT; | |
| 1106 } | |
| 1107 } | |
| 153 | 1108 // we will accept the recipient, but add an auto-whitelist entry |
| 1109 // if needed to ensure we can accept replies | |
| 162 | 1110 loto = to_lower_string(rcptaddr); |
| 1111 WHITELISTERP w = con2.find_autowhite(loto, priv.mailaddr); | |
| 153 | 1112 if (w) { |
| 156 | 1113 if (debug_syslog > 1) { |
| 1114 char buf[maxlen]; | |
| 1115 char msg[maxlen]; | |
| 159 | 1116 snprintf(msg, sizeof(msg), "whitelist reply from <%s> in context %s", loto, con2.get_full_name(buf,maxlen)); |
| 156 | 1117 my_syslog(&priv, msg); |
| 1118 } | |
| 154 | 1119 w->sent(loto); // don't free it, the whitelister takes ownership of the string |
| 153 | 1120 } |
| 162 | 1121 else { |
| 1122 free(loto); | |
| 1123 } | |
| 179 | 1124 |
| 94 | 1125 // accept the recipient |
| 1126 if (!con.get_content_filtering()) st = white; | |
| 179 | 1127 |
| 94 | 1128 if (st == oksofar) { |
| 179 | 1129 // remember first content filtering context |
| 1130 if (con.get_content_filtering()) { | |
| 1131 if (!priv.content_context) priv.content_context = &con; | |
| 1132 else if (con.get_require() && (priv.content_context != &con)) { | |
| 1133 smfi_setreply(ctx, "452", "4.2.1", "incompatible filtering contexts"); | |
| 1134 return SMFIS_TEMPFAIL; | |
| 1135 } | |
| 1136 } | |
| 1137 // remember the non-whites | |
| 94 | 1138 priv.need_content_filter(rcptaddr, con); |
| 1139 priv.only_whites = false; | |
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1140 priv.want_spamassassin |= (priv.assassin) && // have spam assassin available and |
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1141 (con.get_spamassassin_limit() != 0); // want to use it with a non-zero score |
| 178 | 1142 priv.want_dccgrey |= (priv.dccifd) && // have dcc interface and |
| 1143 (con.get_grey()); // want to use it for greylisting | |
| 1144 priv.want_dccbulk |= (priv.dccifd) && // have dcc interface and | |
| 1145 (con.get_bulk() != 0); // want to use it for bulk detection | |
| 94 | 1146 } |
| 1147 if (st == white) { | |
| 1148 priv.have_whites = true; | |
| 1149 } | |
| 1150 return SMFIS_CONTINUE; | |
| 1151 } | |
| 1152 | |
| 163 | 1153 sfsistat mlfi_header(SMFICTX* ctx, char* headerf, char* headerv) |
| 1154 { | |
| 1155 mlfiPriv &priv = *MLFIPRIV; | |
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1156 if (priv.authenticated) return SMFIS_CONTINUE; |
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1157 if (priv.only_whites) return SMFIS_CONTINUE; |
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1158 if (priv.want_spamassassin) priv.assassin->mlfi_header(headerf, headerv); |
| 178 | 1159 if (priv.want_dccgrey || priv.want_dccbulk) priv.dccifd->mlfi_header(ctx, headerf, headerv); |
| 163 | 1160 return SMFIS_CONTINUE; |
| 1161 } | |
| 1162 | |
| 1163 sfsistat mlfi_eoh(SMFICTX* ctx) | |
| 1164 { | |
| 1165 mlfiPriv &priv = *MLFIPRIV; | |
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1166 if (priv.authenticated) return SMFIS_CONTINUE; |
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1167 if (priv.only_whites) return SMFIS_CONTINUE; |
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1168 if (priv.want_spamassassin) priv.assassin->mlfi_eoh(); |
| 178 | 1169 if (priv.want_dccgrey || priv.want_dccbulk) priv.dccifd->mlfi_eoh(); |
| 163 | 1170 return SMFIS_CONTINUE; |
| 1171 } | |
| 1172 | |
| 94 | 1173 sfsistat mlfi_body(SMFICTX *ctx, u_char *data, size_t len) |
| 1174 { | |
| 1175 mlfiPriv &priv = *MLFIPRIV; | |
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1176 if (priv.authenticated) return SMFIS_CONTINUE; |
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1177 if (priv.only_whites) return SMFIS_CONTINUE; |
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1178 if (priv.want_spamassassin) priv.assassin->mlfi_body(data, len); |
| 178 | 1179 if (priv.want_dccgrey || priv.want_dccbulk) priv.dccifd->mlfi_body(data, len); |
| 94 | 1180 priv.scanner->scan(data, len); |
| 1181 return SMFIS_CONTINUE; | |
| 1182 } | |
| 1183 | |
| 1184 sfsistat mlfi_eom(SMFICTX *ctx) | |
| 1185 { | |
| 1186 sfsistat rc; | |
| 1187 mlfiPriv &priv = *MLFIPRIV; | |
| 1188 CONFIG &dc = *priv.pc; | |
| 1189 char *host = NULL; | |
| 1190 int ip; | |
| 1191 status st; | |
| 1192 // process end of message | |
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1193 priv.eom = true; |
| 94 | 1194 if (priv.authenticated || priv.only_whites) rc = SMFIS_CONTINUE; |
| 1195 else { | |
| 178 | 1196 // assert env_to not empty, it contains the |
| 1197 // non-whitelisted folks that want content filtering | |
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1198 int score = (priv.want_spamassassin) ? priv.assassin->mlfi_eom() : 0; |
| 181 | 1199 bool grey = false; |
| 1200 int bulk = 0; | |
| 1201 if (priv.want_dccgrey || priv.want_dccbulk) priv.dccifd->mlfi_eom(grey, bulk); | |
| 178 | 1202 |
| 185 | 1203 char buf[maxlen]; |
| 1204 string msg; | |
| 1205 string_set alive; | |
| 1206 bool random = false; | |
| 1207 int limit = 0; | |
| 1208 for (context_map::iterator i=priv.env_to.begin(); i!=priv.env_to.end(); i++) { | |
| 1209 char *rcpt = (*i).first; | |
| 1210 CONTEXT &con = *((*i).second); | |
| 1211 if (!con.acceptable_content(*priv.memory, score, bulk, msg)) { | |
| 1212 // bad html tags or excessive hosts or | |
| 1213 // high spam assassin score or dcc bulk threshold exceedeed | |
| 1214 smfi_delrcpt(ctx, rcpt); | |
| 1215 } | |
| 1216 else { | |
| 1217 alive.insert(rcpt); | |
| 1218 random |= con.get_host_random(); | |
| 1219 limit = max(limit, con.get_host_limit()); | |
| 1220 } | |
| 178 | 1221 } |
| 185 | 1222 bool rejecting = alive.empty(); // if alive is empty, we must have set msg above in acceptable_content() |
| 1223 if (!rejecting) { | |
| 1224 char *fmt, *found; | |
| 1225 if (check_hosts(priv, random, limit, fmt, host, ip, found)) { | |
| 1226 if (found) { | |
| 1227 // uribl style | |
| 1228 snprintf(buf, sizeof(buf), fmt, host, found); | |
| 178 | 1229 } |
| 1230 else { | |
| 185 | 1231 // dnsbl style |
| 1232 char adr[sizeof "255.255.255.255 "]; | |
| 1233 adr[0] = '\0'; | |
| 1234 inet_ntop(AF_INET, (const u_char *)&ip, adr, sizeof(adr)); | |
| 1235 snprintf(buf, sizeof(buf), fmt, host, adr); | |
| 178 | 1236 } |
| 185 | 1237 msg = string(buf); |
| 1238 rejecting = true; | |
| 1239 } | |
| 1240 } | |
| 1241 if (!rejecting) { | |
| 1242 if (priv.want_dccgrey && grey) { | |
| 1243 smfi_setreply(ctx, "452", "4.2.1", "temporary greylist embargoed"); | |
| 1244 rc = SMFIS_TEMPFAIL; | |
| 178 | 1245 } |
| 185 | 1246 else rc = SMFIS_CONTINUE; |
| 1247 } | |
| 1248 else if (!priv.have_whites) { | |
| 1249 // can reject the entire message | |
| 1250 snprintf(buf, sizeof(buf), "%s", msg.c_str()); | |
| 1251 smfi_setreply(ctx, "550", "5.7.1", buf); | |
| 1252 rc = SMFIS_REJECT; | |
| 1253 } | |
| 1254 else { | |
| 1255 // need to accept it but remove the recipients that don't want it | |
| 1256 for (string_set::iterator i=alive.begin(); i!=alive.end(); i++) { | |
| 1257 char *rcpt = *i; | |
| 1258 smfi_delrcpt(ctx, rcpt); | |
| 178 | 1259 } |
| 185 | 1260 rc = SMFIS_CONTINUE; |
| 94 | 1261 } |
| 1262 } | |
| 1263 // reset for a new message on the same connection | |
| 1264 mlfi_abort(ctx); | |
| 1265 return rc; | |
| 1266 } | |
| 1267 | |
| 1268 sfsistat mlfi_abort(SMFICTX *ctx) | |
| 1269 { | |
| 1270 mlfiPriv &priv = *MLFIPRIV; | |
| 1271 priv.reset(); | |
| 1272 return SMFIS_CONTINUE; | |
| 1273 } | |
| 1274 | |
| 1275 sfsistat mlfi_close(SMFICTX *ctx) | |
| 1276 { | |
| 1277 mlfiPriv *priv = MLFIPRIV; | |
| 1278 if (!priv) return SMFIS_CONTINUE; | |
| 1279 delete priv; | |
| 1280 smfi_setpriv(ctx, NULL); | |
| 1281 return SMFIS_CONTINUE; | |
| 1282 } | |
| 1283 | |
| 1284 struct smfiDesc smfilter = | |
| 1285 { | |
| 1286 "DNSBL", // filter name | |
| 1287 SMFI_VERSION, // version code -- do not change | |
| 1288 SMFIF_DELRCPT, // flags | |
| 1289 mlfi_connect, // connection info filter | |
| 163 | 1290 mlfi_helo, // SMTP HELO command filter |
| 94 | 1291 mlfi_envfrom, // envelope sender filter |
| 1292 mlfi_envrcpt, // envelope recipient filter | |
| 163 | 1293 mlfi_header, // header filter |
| 1294 mlfi_eoh, // end of header | |
| 94 | 1295 mlfi_body, // body block filter |
| 1296 mlfi_eom, // end of message | |
| 1297 mlfi_abort, // message aborted | |
| 1298 mlfi_close, // connection cleanup | |
| 1299 }; | |
| 1300 | |
| 1301 | |
| 1302 //////////////////////////////////////////////// | |
| 1303 // reload the config | |
| 1304 // | |
| 1305 CONFIG* new_conf(); | |
| 1306 CONFIG* new_conf() { | |
| 1307 CONFIG *newc = new CONFIG; | |
| 1308 pthread_mutex_lock(&config_mutex); | |
| 1309 newc->generation = generation++; | |
| 1310 pthread_mutex_unlock(&config_mutex); | |
| 1311 if (debug_syslog) { | |
| 1312 char buf[maxlen]; | |
| 1313 snprintf(buf, sizeof(buf), "loading configuration generation %d", newc->generation); | |
| 1314 my_syslog(buf); | |
| 1315 } | |
| 1316 if (load_conf(*newc, "dnsbl.conf")) { | |
| 1317 newc->load_time = time(NULL); | |
| 1318 return newc; | |
| 1319 } | |
| 1320 delete newc; | |
| 1321 return NULL; | |
| 1322 } | |
| 1323 | |
| 1324 | |
| 1325 //////////////////////////////////////////////// | |
| 1326 // thread to watch the old config files for changes | |
| 146 | 1327 // and reload when needed. |
| 136 | 1328 // we also clear the SMTP AUTH recipient counts hourly |
| 94 | 1329 // |
| 163 | 1330 extern "C" {void* config_loader(void *arg);} |
| 94 | 1331 void* config_loader(void *arg) { |
| 136 | 1332 int loop = 0; |
| 94 | 1333 while (loader_run) { |
| 1334 sleep(180); // look for modifications every 3 minutes | |
| 1335 if (!loader_run) break; | |
| 136 | 1336 loop++; |
| 1337 if (loop == 20) { | |
| 1338 // three minutes thru each loop, 20 loops per hour | |
| 1339 // clear the recipient counts | |
| 1340 pthread_mutex_lock(&rate_mutex); | |
| 138 | 1341 for (rcpt_rates::iterator i=rcpt_counts.begin(); i!=rcpt_counts.end(); i++) { |
| 140 | 1342 (*i).second = 0; |
| 138 | 1343 } |
| 136 | 1344 pthread_mutex_unlock(&rate_mutex); |
| 137 | 1345 loop = 0; |
| 136 | 1346 } |
| 94 | 1347 CONFIG &dc = *config; |
| 1348 time_t then = dc.load_time; | |
| 1349 struct stat st; | |
| 1350 bool reload = false; | |
| 1351 for (string_set::iterator i=dc.config_files.begin(); i!=dc.config_files.end(); i++) { | |
| 1352 char *fn = *i; | |
| 1353 if (stat(fn, &st)) reload = true; // file disappeared | |
| 1354 else if (st.st_mtime > then) reload = true; // file modified | |
| 1355 if (reload) break; | |
| 1356 } | |
| 1357 if (reload) { | |
| 1358 CONFIG *newc = new_conf(); | |
| 1359 if (newc) { | |
| 1360 // replace the global config pointer | |
| 1361 pthread_mutex_lock(&config_mutex); | |
| 146 | 1362 CONFIG *pc = config; |
| 1363 bool last = pc && (!pc->reference_count); | |
| 94 | 1364 config = newc; |
| 1365 pthread_mutex_unlock(&config_mutex); | |
| 163 | 1366 if (last) delete pc; // there were no references to this config |
| 94 | 1367 } |
| 1368 else { | |
| 1369 // failed to load new config | |
| 1370 my_syslog("failed to load new configuration"); | |
| 1371 system("echo 'failed to load new dnsbl configuration from /etc/dnsbl' | mail -s 'error in /etc/dnsbl configuration' root"); | |
| 1372 // update the load time on the current config to prevent complaining every 3 minutes | |
| 1373 dc.load_time = time(NULL); | |
| 1374 } | |
| 1375 } | |
| 1376 } | |
| 1377 return NULL; | |
| 1378 } | |
| 1379 | |
| 1380 | |
| 1381 void usage(char *prog); | |
| 1382 void usage(char *prog) | |
| 1383 { | |
| 177 | 1384 fprintf(stderr, "Usage: %s [-d [level]] [-c] [-s] [-e from|to] [-b dccifd-addr] -r port -p sm-sock-addr [-t timeout]\n", prog); |
| 1385 fprintf(stderr, "where dccifd_addr is for the connection to dccifd\n"); | |
| 1386 fprintf(stderr, " and should be local-domain-socket-file-name\n"); | |
| 94 | 1387 fprintf(stderr, "where port is for the connection to our own dns resolver processes\n"); |
| 1388 fprintf(stderr, " and should be local-domain-socket-file-name\n"); | |
| 1389 fprintf(stderr, "where sm-sock-addr is for the connection to sendmail\n"); | |
| 1390 fprintf(stderr, " and should be one of\n"); | |
| 1391 fprintf(stderr, " inet:port@ip-address\n"); | |
| 1392 fprintf(stderr, " local:local-domain-socket-file-name\n"); | |
| 1393 fprintf(stderr, "-c will load and dump the config to stdout\n"); | |
| 1394 fprintf(stderr, "-s will stress test the config loading code by repeating the load/free cycle\n"); | |
| 1395 fprintf(stderr, " in an infinte loop.\n"); | |
| 1396 fprintf(stderr, "-d will set the syslog message level, currently 0 to 3\n"); | |
| 1397 fprintf(stderr, "-e will print the results of looking up the from and to addresses in the\n"); | |
| 1398 fprintf(stderr, " current config. The | character is used to separate the from and to\n"); | |
| 1399 fprintf(stderr, " addresses in the argument to the -e switch\n"); | |
| 1400 } | |
| 1401 | |
| 1402 | |
| 1403 | |
| 1404 void setup_socket(char *sock); | |
| 1405 void setup_socket(char *sock) { | |
| 1406 unlink(sock); | |
| 1407 } | |
| 1408 | |
| 1409 | |
| 1410 /* | |
| 1411 * The signal handler function -- only gets called when a SIGCHLD | |
| 1412 * is received, ie when a child terminates | |
| 1413 */ | |
| 1414 void sig_chld(int signo) | |
| 1415 { | |
| 1416 int status; | |
| 1417 /* Wait for any child without blocking */ | |
| 1418 while (waitpid(-1, &status, WNOHANG) > 0) { | |
| 1419 // ignore child exit status, we only do this to cleanup zombies | |
| 1420 } | |
| 1421 } | |
| 1422 | |
| 1423 | |
| 1424 int main(int argc, char**argv) | |
| 1425 { | |
| 1426 token_init(); | |
| 1427 bool check = false; | |
| 1428 bool stress = false; | |
| 1429 bool setconn = false; | |
| 1430 bool setreso = false; | |
| 1431 char *email = NULL; | |
| 1432 int c; | |
| 177 | 1433 const char *args = "b:r:p:t:e:d:chs"; |
| 94 | 1434 extern char *optarg; |
| 1435 | |
| 1436 // Process command line options | |
| 1437 while ((c = getopt(argc, argv, args)) != -1) { | |
| 1438 switch (c) { | |
| 177 | 1439 case 'b': |
| 1440 if (optarg == NULL || *optarg == '\0') { | |
| 1441 fprintf(stderr, "Illegal dccifd socket: %s\n", optarg); | |
| 1442 exit(EX_USAGE); | |
| 1443 } | |
| 1444 dccifd_port = strdup(optarg); | |
| 1445 break; | |
| 1446 | |
| 94 | 1447 case 'r': |
| 1448 if (optarg == NULL || *optarg == '\0') { | |
| 1449 fprintf(stderr, "Illegal resolver socket: %s\n", optarg); | |
| 1450 exit(EX_USAGE); | |
| 1451 } | |
| 1452 resolver_port = strdup(optarg); | |
| 1453 setup_socket(resolver_port); | |
| 1454 setreso = true; | |
| 1455 break; | |
| 1456 | |
| 1457 case 'p': | |
| 1458 if (optarg == NULL || *optarg == '\0') { | |
| 1459 fprintf(stderr, "Illegal sendmail socket: %s\n", optarg); | |
| 1460 exit(EX_USAGE); | |
| 1461 } | |
| 1462 if (smfi_setconn(optarg) == MI_FAILURE) { | |
| 1463 fprintf(stderr, "smfi_setconn failed\n"); | |
| 1464 exit(EX_SOFTWARE); | |
| 1465 } | |
| 1466 if (strncasecmp(optarg, "unix:", 5) == 0) setup_socket(optarg + 5); | |
| 1467 else if (strncasecmp(optarg, "local:", 6) == 0) setup_socket(optarg + 6); | |
| 1468 setconn = true; | |
| 1469 break; | |
| 1470 | |
| 1471 case 't': | |
| 1472 if (optarg == NULL || *optarg == '\0') { | |
| 1473 fprintf(stderr, "Illegal timeout: %s\n", optarg); | |
| 1474 exit(EX_USAGE); | |
| 1475 } | |
| 1476 if (smfi_settimeout(atoi(optarg)) == MI_FAILURE) { | |
| 1477 fprintf(stderr, "smfi_settimeout failed\n"); | |
| 1478 exit(EX_SOFTWARE); | |
| 1479 } | |
| 1480 break; | |
| 1481 | |
| 1482 case 'e': | |
| 1483 if (email) free(email); | |
| 1484 email = strdup(optarg); | |
| 1485 break; | |
| 1486 | |
| 1487 case 'c': | |
| 1488 check = true; | |
| 1489 break; | |
| 1490 | |
| 1491 case 's': | |
| 1492 stress = true; | |
| 1493 break; | |
| 1494 | |
| 1495 case 'd': | |
| 1496 if (optarg == NULL || *optarg == '\0') debug_syslog = 1; | |
| 1497 else debug_syslog = atoi(optarg); | |
| 1498 break; | |
| 1499 | |
| 1500 case 'h': | |
| 1501 default: | |
| 1502 usage(argv[0]); | |
| 1503 exit(EX_USAGE); | |
| 1504 } | |
| 1505 } | |
| 1506 | |
| 1507 if (check) { | |
| 1508 use_syslog = false; | |
| 1509 debug_syslog = 10; | |
| 1510 CONFIG *conf = new_conf(); | |
| 1511 if (conf) { | |
| 1512 conf->dump(); | |
| 1513 delete conf; | |
| 164 | 1514 clear_strings(); // for valgrind checking |
| 94 | 1515 return 0; |
| 1516 } | |
| 1517 else { | |
| 1518 return 1; // config failed to load | |
| 1519 } | |
| 1520 } | |
| 1521 | |
| 1522 if (stress) { | |
| 1523 fprintf(stdout, "stress testing\n"); | |
| 1524 while (1) { | |
| 1525 for (int i=0; i<10; i++) { | |
| 1526 CONFIG *conf = new_conf(); | |
| 1527 if (conf) delete conf; | |
| 1528 } | |
| 1529 fprintf(stdout, "."); | |
| 1530 fflush(stdout); | |
| 1531 sleep(1); | |
| 1532 } | |
| 1533 } | |
| 1534 | |
| 1535 if (email) { | |
| 1536 char *x = strchr(email, '|'); | |
| 1537 if (x) { | |
| 1538 *x = '\0'; | |
| 1539 char *from = strdup(email); | |
| 1540 char *to = strdup(x+1); | |
| 1541 use_syslog = false; | |
| 1542 CONFIG *conf = new_conf(); | |
| 1543 if (conf) { | |
| 1544 CONTEXTP con = conf->find_context(to); | |
| 1545 char buf[maxlen]; | |
| 1546 fprintf(stdout, "envelope to <%s> finds context %s\n", to, con->get_full_name(buf,maxlen)); | |
| 1547 CONTEXTP fc = con->find_context(from); | |
| 1548 fprintf(stdout, "envelope from <%s> finds context %s\n", from, fc->get_full_name(buf,maxlen)); | |
| 1549 char *st = fc->find_from(from); | |
| 1550 fprintf(stdout, "envelope from <%s> finds status %s\n", from, st); | |
| 1551 delete conf; | |
| 1552 } | |
| 1553 } | |
| 1554 return 0; | |
| 1555 } | |
| 1556 | |
| 1557 if (!setconn) { | |
| 1558 fprintf(stderr, "%s: Missing required -p argument\n", argv[0]); | |
| 1559 usage(argv[0]); | |
| 1560 exit(EX_USAGE); | |
| 1561 } | |
| 1562 | |
| 1563 if (!setreso) { | |
| 1564 fprintf(stderr, "%s: Missing required -r argument\n", argv[0]); | |
| 1565 usage(argv[0]); | |
| 1566 exit(EX_USAGE); | |
| 1567 } | |
| 1568 | |
| 1569 if (smfi_register(smfilter) == MI_FAILURE) { | |
| 1570 fprintf(stderr, "smfi_register failed\n"); | |
| 1571 exit(EX_UNAVAILABLE); | |
| 1572 } | |
| 1573 | |
| 1574 // switch to background mode | |
| 1575 if (daemon(1,0) < 0) { | |
| 1576 fprintf(stderr, "daemon() call failed\n"); | |
| 1577 exit(EX_UNAVAILABLE); | |
| 1578 } | |
| 1579 | |
| 1580 // write the pid | |
| 1581 const char *pidpath = "/var/run/dnsbl.pid"; | |
| 1582 unlink(pidpath); | |
| 1583 FILE *f = fopen(pidpath, "w"); | |
| 1584 if (f) { | |
| 1585 #ifdef linux | |
| 1586 // from a comment in the DCC source code: | |
| 1587 // Linux threads are broken. Signals given the | |
| 1588 // original process are delivered to only the | |
| 1589 // thread that happens to have that PID. The | |
| 1590 // sendmail libmilter thread that needs to hear | |
| 1591 // SIGINT and other signals does not, and that breaks | |
| 1592 // scripts that need to stop milters. | |
| 1593 // However, signaling the process group works. | |
| 1594 fprintf(f, "-%d\n", (u_int)getpgrp()); | |
| 1595 #else | |
| 1596 fprintf(f, "%d\n", (u_int)getpid()); | |
| 1597 #endif | |
| 1598 fclose(f); | |
| 1599 } | |
| 1600 | |
| 1601 // initialize the thread sync objects | |
| 1602 pthread_mutex_init(&config_mutex, 0); | |
| 1603 pthread_mutex_init(&syslog_mutex, 0); | |
| 1604 pthread_mutex_init(&resolve_mutex, 0); | |
| 1605 pthread_mutex_init(&fd_pool_mutex, 0); | |
| 153 | 1606 pthread_mutex_init(&verifier_mutex, 0); |
| 1607 pthread_mutex_init(&whitelister_mutex, 0); | |
| 94 | 1608 |
| 1609 // drop root privs | |
| 1610 struct passwd *pw = getpwnam("dnsbl"); | |
| 1611 if (pw) { | |
| 1612 if (setgid(pw->pw_gid) == -1) { | |
| 1613 my_syslog("failed to switch to group dnsbl"); | |
| 1614 } | |
| 1615 if (setuid(pw->pw_uid) == -1) { | |
| 1616 my_syslog("failed to switch to user dnsbl"); | |
| 1617 } | |
| 1618 } | |
| 1619 | |
| 1620 // load the initial config | |
| 1621 config = new_conf(); | |
| 1622 if (!config) { | |
| 1623 my_syslog("failed to load initial configuration, quitting"); | |
| 1624 exit(1); | |
| 1625 } | |
| 1626 | |
| 1627 // fork off the resolver listener process | |
| 1628 pid_t child = fork(); | |
| 1629 if (child < 0) { | |
| 1630 my_syslog("failed to create resolver listener process"); | |
| 1631 exit(0); | |
| 1632 } | |
| 1633 if (child == 0) { | |
| 1634 // we are the child - dns resolver listener process | |
| 1635 resolver_socket = socket(AF_UNIX, SOCK_STREAM, 0); | |
| 1636 if (resolver_socket < 0) { | |
| 1637 my_syslog("child failed to create resolver socket"); | |
| 1638 exit(0); // failed | |
| 1639 } | |
| 1640 sockaddr_un server; | |
| 1641 memset(&server, '\0', sizeof(server)); | |
| 1642 server.sun_family = AF_UNIX; | |
| 1643 strncpy(server.sun_path, resolver_port, sizeof(server.sun_path)-1); | |
| 1644 //try to bind the address to the socket. | |
| 1645 if (bind(resolver_socket, (sockaddr *)&server, sizeof(server)) < 0) { | |
| 1646 // bind failed | |
| 1647 shutdown(resolver_socket, SHUT_RDWR); | |
| 1648 close(resolver_socket); | |
| 1649 my_syslog("child failed to bind resolver socket"); | |
| 1650 exit(0); // failed | |
| 1651 } | |
| 1652 //listen on the socket. | |
| 1653 if (listen(resolver_socket, 10) < 0) { | |
| 1654 // listen failed | |
| 1655 shutdown(resolver_socket, SHUT_RDWR); | |
| 1656 close(resolver_socket); | |
| 1657 my_syslog("child failed to listen to resolver socket"); | |
| 1658 exit(0); // failed | |
| 1659 } | |
| 1660 // setup sigchld handler to prevent zombies | |
| 1661 struct sigaction act; | |
| 1662 act.sa_handler = sig_chld; // Assign sig_chld as our SIGCHLD handler | |
| 1663 sigemptyset(&act.sa_mask); // We don't want to block any other signals in this example | |
| 1664 act.sa_flags = SA_NOCLDSTOP; // only want children that have terminated | |
| 1665 if (sigaction(SIGCHLD, &act, NULL) < 0) { | |
| 1666 my_syslog("child failed to setup SIGCHLD handler"); | |
| 1667 exit(0); // failed | |
| 1668 } | |
| 1669 while (true) { | |
| 1670 sockaddr_un client; | |
| 1671 socklen_t clientlen = sizeof(client); | |
| 1672 int s = accept(resolver_socket, (sockaddr *)&client, &clientlen); | |
| 1673 if (s > 0) { | |
| 1674 // accept worked, it did not get cancelled before we could accept it | |
| 1675 // fork off a process to handle this connection | |
| 1676 int newchild = fork(); | |
| 1677 if (newchild == 0) { | |
| 1678 // this is the worker process | |
| 1679 // child does not need the listening socket | |
| 1680 close(resolver_socket); | |
| 1681 process_resolver_requests(s); | |
| 1682 exit(0); | |
| 1683 } | |
| 1684 else { | |
| 1685 // this is the parent | |
| 1686 // parent does not need the accepted socket | |
| 1687 close(s); | |
| 1688 } | |
| 1689 } | |
| 1690 } | |
| 1691 exit(0); // make sure we don't fall thru. | |
| 1692 } | |
| 1693 else { | |
| 1694 sleep(2); // allow child to get started | |
| 1695 } | |
| 1696 | |
| 1697 // only create threads after the fork() in daemon | |
| 1698 pthread_t tid; | |
| 1699 if (pthread_create(&tid, 0, config_loader, 0)) | |
| 1700 my_syslog("failed to create config loader thread"); | |
| 1701 if (pthread_detach(tid)) | |
| 1702 my_syslog("failed to detach config loader thread"); | |
| 153 | 1703 |
| 94 | 1704 if (pthread_create(&tid, 0, verify_closer, 0)) |
| 1705 my_syslog("failed to create verify closer thread"); | |
| 1706 if (pthread_detach(tid)) | |
| 1707 my_syslog("failed to detach verify closer thread"); | |
| 1708 | |
| 153 | 1709 if (pthread_create(&tid, 0, whitelister_writer, 0)) |
| 1710 my_syslog("failed to create autowhite writer thread"); | |
| 1711 if (pthread_detach(tid)) | |
| 1712 my_syslog("failed to detach autowhite writer thread"); | |
| 1713 | |
| 94 | 1714 time_t starting = time(NULL); |
| 1715 int rc = smfi_main(); | |
| 1716 if ((rc != MI_SUCCESS) && (time(NULL) > starting+5*60)) { | |
| 1717 my_syslog("trying to restart after smfi_main()"); | |
| 1718 loader_run = false; // eventually the config loader thread will terminate | |
| 1719 execvp(argv[0], argv); | |
| 1720 } | |
| 1721 exit((rc == MI_SUCCESS) ? 0 : EX_UNAVAILABLE); | |
| 1722 } | |
| 1723 |