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Initial revision
author carl
date Tue, 20 Apr 2004 20:02:29 -0700
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-1:000000000000 0:96a9758165cd
1 /*
2
3 Copyright (c) 2004 Carl Byington - 510 Software Group, released under
4 the GPL version 2 or any later version at your choice available at
5 http://www.fsf.org/licenses/gpl.txt
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
10 -p port The port through which the MTA will connect to this milter.
11 -t sec The timeout value.
12
13 TODO:
14
15 1) Add "include-dcc NAME fn" to read a dcc whiteclnt file looking
16 for many substitute mail-host domain, and add the equivalent "env_from
17 domain black" into the NAME mapping. That allows clients to use just the
18 DCC for white/blacklisting, but the backup mx machines can use dnsbl
19 and get the same effect.
20
21 */
22
23
24 // from sendmail sample
25 #include <sys/types.h>
26 #include <sys/stat.h>
27 #include <errno.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <sysexits.h>
32 #include <unistd.h>
33
34 // needed for socket io
35 #include <sys/ioctl.h>
36 #include <net/if.h>
37 #include <arpa/inet.h>
38 #include <netinet/in.h>
39 #include <netinet/tcp.h>
40 #include <netdb.h>
41 #include <sys/socket.h>
42
43 // needed for thread
44 #include <pthread.h>
45
46 // needed for std c++ collections
47 #include <set>
48 #include <map>
49 #include <list>
50
51 // for the dns resolver
52 #include <netinet/in.h>
53 #include <arpa/nameser.h>
54 #include <resolv.h>
55
56 // misc stuff needed here
57 #include <ctype.h>
58 #include <fstream>
59 #include <syslog.h>
60
61
62 using namespace std;
63
64
65 extern "C" {
66 #include "libmilter/mfapi.h"
67 sfsistat mlfi_connect(SMFICTX *ctx, char *hostname, _SOCK_ADDR *hostaddr);
68 sfsistat mlfi_envfrom(SMFICTX *ctx, char **argv);
69 sfsistat mlfi_envrcpt(SMFICTX *ctx, char **argv);
70 sfsistat mlfi_eom_or_abort(SMFICTX *ctx);
71 sfsistat mlfi_close(SMFICTX *ctx);
72 }
73
74 #ifndef bool
75 # define bool int
76 # define TRUE 1
77 # define FALSE 0
78 #endif /* ! bool */
79
80 struct ltstr {
81 bool operator()(char* s1, char* s2) const {
82 return strcmp(s1, s2) < 0;
83 }
84 };
85
86 struct DNSBL {
87 char *suffix; // blacklist suffix like blackholes.five-ten-sg.com
88 char *message; // error message with one or two %s operators for the ip address replacement
89 DNSBL(char *s, char *m);
90 };
91 DNSBL::DNSBL(char *s, char *m) {
92 suffix = s;
93 message = m;
94 }
95
96 typedef DNSBL * DNSBLP;
97 typedef list<DNSBLP> DNSBLL;
98 typedef DNSBLL * DNSBLLP;
99 typedef map<char *, char *, ltstr> string_map;
100 typedef map<char *, string_map *, ltstr> from_map;
101 typedef map<char *, DNSBLP, ltstr> dnsblp_map;
102 typedef map<char *, DNSBLLP, ltstr> dnsbllp_map;
103 typedef set<char *, ltstr> string_set;
104 typedef list<char *> string_list;
105
106 struct CONFIG {
107 // the only mutable stuff once it has been loaded from the config file
108 int reference_count; // protected by the global config_mutex
109 // all the rest is constant after loading from the config file
110 time_t load_time;
111 string_list config_files;
112 dnsblp_map dnsbls;
113 dnsbllp_map dnsblls;
114 from_map env_from;
115 string_map env_to_dnsbll; // map recipient to a named dnsbll
116 string_map env_to_chkfrom; // map recipient to a named from map
117 CONFIG();
118 ~CONFIG();
119 };
120 CONFIG::CONFIG() {
121 reference_count = 0;
122 load_time = 0;
123 }
124 CONFIG::~CONFIG() {
125 for (dnsblp_map::iterator i=dnsbls.begin(); i!=dnsbls.end(); i++) {
126 DNSBLP d = (*i).second;
127 delete d;
128 }
129 for (dnsbllp_map::iterator i=dnsblls.begin(); i!=dnsblls.end(); i++) {
130 DNSBLLP d = (*i).second;
131 delete d;
132 }
133 for (from_map::iterator i=env_from.begin(); i!=env_from.end(); i++) {
134 string_map *d = (*i).second;
135 delete d;
136 }
137 }
138
139 static string_set all_strings; // owns all the strings, only modified by the config loader thread
140 static CONFIG * config = NULL; // protected by the config_mutex
141
142 static pthread_mutex_t config_mutex;
143 static pthread_mutex_t syslog_mutex;
144 static pthread_mutex_t resolve_mutex;
145
146
147
148 ////////////////////////////////////////////////
149 // predefined names
150 //
151 #define DEFAULT "default"
152 #define WHITE "white"
153 #define BLACK "black"
154
155
156 ////////////////////////////////////////////////
157 // mail filter private data, held for us by sendmail
158 //
159 enum status {oksofar, // not rejected yet
160 white, // whitelisted by envelope from
161 black, // blacklisted by envelope from or to
162 reject}; // rejected by a dns list
163 struct mlfiPriv
164 {
165 CONFIG *pc; // global context with our maps
166 int ip; // ip4 address of the smtp client
167 char *mailaddr; // envelope from value
168 bool authenticated; // client authenticated? if so, suppress all dnsbl checks
169 map<DNSBLP, status> checked; // status from those lists
170 mlfiPriv();
171 ~mlfiPriv();
172 };
173 mlfiPriv::mlfiPriv() {
174 pthread_mutex_lock(&config_mutex);
175 pc = config;
176 pc->reference_count++;
177 pthread_mutex_unlock(&config_mutex);
178 ip = 0;
179 mailaddr = NULL;
180 }
181 mlfiPriv::~mlfiPriv() {
182 pthread_mutex_lock(&config_mutex);
183 pc->reference_count--;
184 pthread_mutex_unlock(&config_mutex);
185 if (mailaddr) free(mailaddr);
186 }
187
188 #define MLFIPRIV ((struct mlfiPriv *) smfi_getpriv(ctx))
189
190
191 ////////////////////////////////////////////////
192 // syslog a message
193 //
194 static void my_syslog(char *text);
195 static void my_syslog(char *text) {
196 pthread_mutex_lock(&syslog_mutex);
197 openlog("dnsbl", LOG_PID, LOG_MAIL);
198 syslog(LOG_NOTICE, "%s", text);
199 closelog();
200 pthread_mutex_unlock(&syslog_mutex);
201 }
202
203
204 ////////////////////////////////////////////////
205 // register a global string
206 //
207 static char* register_string(char *name);
208 static char* register_string(char *name) {
209 string_set::iterator i = all_strings.find(name);
210 if (i != all_strings.end()) return *i;
211 char *x = strdup(name);
212 all_strings.insert(x);
213 return x;
214 }
215
216
217 static char* next_token(char *delim);
218 static char* next_token(char *delim) {
219 char *name = strtok(NULL, delim);
220 if (!name) return name;
221 return register_string(name);
222 }
223
224
225 ////////////////////////////////////////////////
226 // lookup an email address in the env_from or env_to maps
227 //
228 static char* lookup1(char *email, string_map map);
229 static char* lookup1(char *email, string_map map) {
230 string_map::iterator i = map.find(email);
231 if (i != map.end()) return (*i).second;
232 char *x = strchr(email, '@');
233 if (!x) return DEFAULT;
234 x++;
235 i = map.find(x);
236 if (i != map.end()) return (*i).second;
237 return DEFAULT;
238 }
239
240
241 ////////////////////////////////////////////////
242 // lookup an email address in the env_from or env_to maps
243 // this email address is passed in from sendmail, and will
244 // always be enclosed in <>. It may have mixed case, just
245 // as the mail client sent it.
246 //
247 static char* lookup(char* email, string_map map);
248 static char* lookup(char* email, string_map map) {
249 int n = strlen(email)-2;
250 if (n < 1) return DEFAULT; // malformed
251 char *key = strdup(email+1);
252 key[n] = '\0';
253 for (int i=0; i<n; i++) key[i] = tolower(key[i]);
254 char *rc = lookup1(key, map);
255 free(key);
256 return rc;
257 }
258
259
260 ////////////////////////////////////////////////
261 // find the dnsbl with a specific name
262 //
263 static DNSBLP find_dnsbl(CONFIG &dc, char *name);
264 static DNSBLP find_dnsbl(CONFIG &dc, char *name) {
265 dnsblp_map::iterator i = dc.dnsbls.find(name);
266 if (i == dc.dnsbls.end()) return NULL;
267 return (*i).second;
268 }
269
270
271 ////////////////////////////////////////////////
272 // find the dnsbll with a specific name
273 //
274 static DNSBLLP find_dnsbll(CONFIG &dc, char *name);
275 static DNSBLLP find_dnsbll(CONFIG &dc, char *name) {
276 dnsbllp_map::iterator i = dc.dnsblls.find(name);
277 if (i == dc.dnsblls.end()) return NULL;
278 return (*i).second;
279 }
280
281
282 ////////////////////////////////////////////////
283 // find the envfrom map with a specific name
284 //
285 static string_map* find_from_map(CONFIG &dc, char *name);
286 static string_map* find_from_map(CONFIG &dc, char *name) {
287 from_map::iterator i = dc.env_from.find(name);
288 if (i == dc.env_from.end()) return NULL;
289 return (*i).second;
290 }
291
292
293 static string_map& really_find_from_map(CONFIG &dc, char *name);
294 static string_map& really_find_from_map(CONFIG &dc, char *name) {
295 string_map *sm = find_from_map(dc, name);
296 if (!sm) {
297 sm = new string_map;
298 dc.env_from[name] = sm;
299 }
300 return *sm;
301 }
302
303
304 ////////////////////////////////////////////////
305 // check a single dnsbl - we don't try very hard, just
306 // using the default resolver retry settings. If we cannot
307 // get an answer, we just accept the mail. The caller
308 // must ensure thread safety.
309 //
310 static status check_single(int ip, DNSBL &bl);
311 static status check_single(int ip, DNSBL &bl) {
312 // make a dns question
313 const u_char *src = (const u_char *)&ip;
314 if (src[0] == 127) return oksofar; // don't do dns lookups on localhost
315 char question[NS_MAXDNAME];
316 snprintf(question, sizeof(question), "%u.%u.%u.%u.%s.", src[3], src[2], src[1], src[0], bl.suffix);
317 // ask the question
318 u_char answer[NS_PACKETSZ];
319 int length = res_search(question, ns_c_in, ns_t_a, answer, sizeof(answer));
320 if (length < 0) return oksofar; // error in getting answer
321 // parse the answer
322 ns_msg handle;
323 ns_rr rr;
324 if (ns_initparse(answer, length, &handle) != 0) return oksofar;
325 int rrnum = 0;
326 while (ns_parserr(&handle, ns_s_an, rrnum++, &rr) == 0) {
327 if (ns_rr_type(rr) == ns_t_a) {
328 // we see an A record, implies blacklisted ip address
329 return reject;
330 }
331 }
332 return oksofar;
333 }
334
335
336 ////////////////////////////////////////////////
337 // check the dnsbls specified for this recipient
338 //
339 static status check_dnsbl(mlfiPriv &priv, DNSBLLP dnsbllp, DNSBLP &rejectlist);
340 static status check_dnsbl(mlfiPriv &priv, DNSBLLP dnsbllp, DNSBLP &rejectlist) {
341 if (priv.authenticated) return oksofar;
342 if (!dnsbllp) return oksofar;
343 DNSBLL &dnsbll = *dnsbllp;
344 for (DNSBLL::iterator i=dnsbll.begin(); i!=dnsbll.end(); i++) {
345 DNSBLP dp = *i; // non null by construction
346 status st;
347 map<DNSBLP, status>::iterator f = priv.checked.find(dp);
348 if (f == priv.checked.end()) {
349 // have not checked this list yet
350 pthread_mutex_lock(&resolve_mutex);
351 st = check_single(priv.ip, *dp);
352 pthread_mutex_unlock(&resolve_mutex);
353 rejectlist = dp;
354 priv.checked[dp] = st;
355 }
356 else {
357 st = (*f).second;
358 rejectlist = (*f).first;
359 }
360 if (st == reject) return st;
361 }
362 return oksofar;
363 }
364
365
366 ////////////////////////////////////////////////
367 // start of sendmail milter interfaces
368 //
369 sfsistat mlfi_connect(SMFICTX *ctx, char *hostname, _SOCK_ADDR *hostaddr)
370 {
371 // allocate some private memory
372 mlfiPriv *priv = new mlfiPriv;
373 if (hostaddr->sa_family == AF_INET) {
374 priv->ip = ((struct sockaddr_in *)hostaddr)->sin_addr.s_addr;
375 }
376
377 // save the private data
378 smfi_setpriv(ctx, (void*)priv);
379
380 // continue processing
381 return SMFIS_CONTINUE;
382 }
383
384 sfsistat mlfi_envfrom(SMFICTX *ctx, char **from)
385 {
386 mlfiPriv &priv = *MLFIPRIV;
387 priv.mailaddr = strdup(from[0]);
388 priv.authenticated = (smfi_getsymval(ctx, "{auth_authen}") != NULL);
389 return SMFIS_CONTINUE;
390 }
391
392 sfsistat mlfi_envrcpt(SMFICTX *ctx, char **rcpt)
393 {
394 DNSBLP rejectlist = NULL; // list that caused the reject
395 status st = oksofar;
396 mlfiPriv &priv = *MLFIPRIV;
397 CONFIG &dc = *priv.pc;
398 char *rcptaddr = rcpt[0];
399 char *dnsname = lookup(rcptaddr, dc.env_to_dnsbll);
400 char *fromname = lookup(rcptaddr, dc.env_to_chkfrom);
401 if ((strcmp(dnsname, BLACK) == 0) ||
402 (strcmp(fromname, BLACK) == 0)) {
403 st = black; // two options to blacklist this recipient
404 }
405 else if (strcmp(fromname, WHITE) == 0) {
406 st = white;
407 }
408 else {
409 // check an env_from map
410 string_map *sm = find_from_map(dc, fromname);
411 if (sm != NULL) {
412 fromname = lookup(priv.mailaddr, *sm); // returns default if name not in map
413 if (strcmp(fromname, BLACK) == 0) {
414 st = black; // blacklist this envelope from value
415 }
416 if (strcmp(fromname, WHITE) == 0) {
417 st = white; // blacklist this envelope from value
418 }
419 }
420 }
421 if ((st == oksofar) && (strcmp(dnsname, WHITE) != 0)) {
422 // check dns lists
423 st = check_dnsbl(priv, find_dnsbll(dc, dnsname), rejectlist);
424 }
425
426 if (st == reject) {
427 // reject the recipient based on some dnsbl
428 char adr[sizeof "255.255.255.255"];
429 adr[0] = '\0';
430 const char *rc = inet_ntop(AF_INET, (const u_char *)&priv.ip, adr, sizeof(adr));
431 char buf[2000];
432 snprintf(buf, sizeof(buf), rejectlist->message, adr, adr);
433 smfi_setreply(ctx, "550", "5.7.1", buf);
434 return SMFIS_REJECT;
435 }
436 else if (st == black) {
437 // reject the recipient based on blacklisting either from or to
438 smfi_setreply(ctx, "550", "5.7.1", "no such user");
439 return SMFIS_REJECT;
440 }
441 else {
442 // accept the recipient
443 return SMFIS_CONTINUE;
444 }
445 }
446
447 sfsistat mlfi_eom_or_abort(SMFICTX *ctx)
448 {
449 mlfiPriv &priv = *MLFIPRIV;
450 if (priv.mailaddr) {
451 free(priv.mailaddr);
452 priv.mailaddr = NULL;
453 }
454 return SMFIS_CONTINUE;
455 }
456
457 sfsistat mlfi_close(SMFICTX *ctx)
458 {
459 mlfiPriv *priv = MLFIPRIV;
460 if (!priv) return SMFIS_CONTINUE;
461 delete priv;
462 smfi_setpriv(ctx, NULL);
463 return SMFIS_CONTINUE;
464 }
465
466 struct smfiDesc smfilter =
467 {
468 "DNSBL", // filter name
469 SMFI_VERSION, // version code -- do not change
470 SMFIF_DELRCPT, // flags
471 mlfi_connect, // connection info filter
472 NULL, // SMTP HELO command filter
473 mlfi_envfrom, // envelope sender filter
474 mlfi_envrcpt, // envelope recipient filter
475 NULL, // header filter
476 NULL, // end of header
477 NULL, // body block filter
478 mlfi_eom_or_abort, // end of message
479 mlfi_eom_or_abort, // message aborted
480 mlfi_close, // connection cleanup
481 };
482
483
484 static void dumpit(char *name, string_map map);
485 static void dumpit(char *name, string_map map) {
486 fprintf(stderr, "\n");
487 for (string_map::iterator i=map.begin(); i!=map.end(); i++) {
488 fprintf(stderr, "%s %s->%s\n", name, (*i).first, (*i).second);
489 }
490 }
491
492
493 static void dumpit(from_map map);
494 static void dumpit(from_map map) {
495 fprintf(stderr, "\n");
496 for (from_map::iterator i=map.begin(); i!=map.end(); i++) {
497 fprintf(stderr, "envfrom map %s\n", (*i).first);
498 string_map *sm = (*i).second;
499 dumpit("envelope from", *sm);
500 }
501 }
502
503
504 static void dumpit();
505 static void dumpit() {
506 CONFIG &dc = *config;
507 fprintf(stderr, "dnsbls\n");
508 for (dnsblp_map::iterator i=dc.dnsbls.begin(); i!=dc.dnsbls.end(); i++) {
509 fprintf(stderr, "%s %s %s\n", (*i).first, (*i).second->suffix, (*i).second->message);
510 }
511 fprintf(stderr, "dnsbl_lists\n");
512 for (dnsbllp_map::iterator i=dc.dnsblls.begin(); i!=dc.dnsblls.end(); i++) {
513 char *name = (*i).first;
514 DNSBLL &dl = *((*i).second);
515 fprintf(stderr, "%s", name);
516 for (DNSBLL::iterator j=dl.begin(); j!=dl.end(); j++) {
517 DNSBL &d = **j;
518 fprintf(stderr, " %s", d.suffix);
519 }
520 fprintf(stderr, "\n");
521 }
522 }
523
524
525 ////////////////////////////////////////////////
526 // load a single config file
527 //
528 static void load_conf(CONFIG &dc, char *fn);
529 static void load_conf(CONFIG &dc, char *fn) {
530 dc.config_files.push_back(fn);
531 map<char*, int, ltstr> commands;
532 enum {dummy, dnsbl, dnsbll, envfrom, envto, include};
533 commands["dnsbl" ] = dnsbl;
534 commands["dnsbl_list"] = dnsbll;
535 commands["env_from" ] = envfrom;
536 commands["env_to" ] = envto;
537 commands["include" ] = include;
538 const int LINE_SIZE = 2000;
539 ifstream is(fn);
540 if (is.fail()) return;
541 char line[LINE_SIZE];
542 char orig[LINE_SIZE];
543 char *delim = " \t";
544 int curline = 0;
545 while (!is.eof()) {
546 is.getline(line, LINE_SIZE);
547 snprintf(orig, sizeof(orig), "%s", line);
548 curline++;
549 int n = strlen(line);
550 for (int i=0; i<n; i++) line[i] = tolower(line[i]);
551 char *cmd = strtok(line, delim);
552 if (cmd && (cmd[0] != '#') && (cmd[0] != '\0')) {
553 // have a decent command
554 bool processed = false;
555 switch (commands[cmd]) {
556 case dnsbl: {
557 // have a new dnsbl to use
558 char *name = next_token(delim);
559 if (!name) break; // no name name
560 if (find_dnsbl(dc, name)) break; // duplicate entry
561 char *suff = strtok(NULL, delim);
562 if (!suff) break; // no dns suffic
563 char *msg = suff + strlen(suff);
564 if ((msg - line) >= strlen(orig)) break; // line ended with the dns suffix
565 msg = strchr(msg+1, '\'');
566 if (!msg) break; // no reply message template
567 msg++; // move over the leading '
568 if ((msg - line) >= strlen(orig)) break; // line ended with the leading quote
569 char *last = strchr(msg, '\'');
570 if (!last) break; // no trailing quote
571 *last = '\0'; // make it a null terminator
572 dc.dnsbls[name] = new DNSBL(register_string(suff), register_string(msg));
573 processed = true;
574 } break;
575
576 case dnsbll: {
577 // define a new combination of dnsbls
578 char *name = next_token(delim);
579 if (!name) break;
580 if (find_dnsbll(dc, name)) break; // duplicate entry
581 char *list = next_token(delim);
582 if (!list || (*list == '\0') || (*list == '#')) break;
583 DNSBLLP d = new DNSBLL;
584 DNSBLP p = find_dnsbl(dc, list);
585 if (p) d->push_back(p);
586 while (true) {
587 list = next_token(delim);
588 if (!list || (*list == '\0') || (*list == '#')) break;
589 DNSBLP p = find_dnsbl(dc, list);
590 if (p) d->push_back(p);
591 }
592 dc.dnsblls[name] = d;
593 processed = true;
594 } break;
595
596 case envfrom: {
597 // add an entry into the named string_map
598 char *name = next_token(delim);
599 if (!name) break;
600 char *from = next_token(delim);
601 if (!from) break;
602 char *list = next_token(delim);
603 if (!list) break;
604 if ((strcmp(list, WHITE) == 0) ||
605 (strcmp(list, BLACK) == 0)) {
606 string_map &fm = really_find_from_map(dc, name);
607 fm[from] = list;
608 processed = true;
609 }
610 else {
611 // list may be the name of a previously defined from_map
612 string_map *m = find_from_map(dc, list);
613 if (m && (strcmp(list,name) != 0)) {
614 string_map &pm = *m;
615 string_map &fm = really_find_from_map(dc, name);
616 fm.insert(pm.begin(), pm.end());
617 processed = true;
618 }
619 }
620 } break;
621
622 case envto: {
623 // define the dnsbl_list and env_from maps to use for this recipient
624 char *to = next_token(delim);
625 if (!to) break;
626 char *list = next_token(delim);
627 if (!list) break;
628 char *from = next_token(delim);
629 if (!from) break;
630 dc.env_to_dnsbll[to] = list;
631 dc.env_to_chkfrom[to] = from;
632 processed = true;
633 } break;
634
635 case include: {
636 char *fn = next_token(delim);
637 if (fn) {
638 bool ok = true;
639 for (string_list::iterator i=dc.config_files.begin(); i!=dc.config_files.end(); i++) {
640 char *f = *i;
641 if (strcmp(f, fn) == 0) {
642 my_syslog("recursive include file detected");
643 ok = false;
644 break;
645 }
646 }
647 if (ok) {
648 load_conf(dc, fn);
649 processed = true;
650 }
651 }
652 } break;
653
654 default: {
655 } break;
656 }
657 if (!processed) {
658 pthread_mutex_lock(&syslog_mutex);
659 openlog("dnsbl", LOG_PID, LOG_MAIL);
660 syslog(LOG_ERR, "ignoring file %s line %d : %s\n", fn, curline, orig);
661 closelog();
662 pthread_mutex_unlock(&syslog_mutex);
663 }
664 }
665 }
666 is.close();
667 }
668
669
670 ////////////////////////////////////////////////
671 // reload the config
672 //
673 static CONFIG* new_conf();
674 static CONFIG* new_conf() {
675 my_syslog("loading new configuration");
676 CONFIG *newc = new CONFIG;
677 load_conf(*newc, "dnsbl.conf");
678 newc->load_time = time(NULL);
679 return newc;
680 }
681
682
683 ////////////////////////////////////////////////
684 // thread to watch the old config files for changes
685 // and reload when needed. we also cleanup old
686 // configs whose reference count has gone to zero.
687 //
688 static void* config_loader(void *arg);
689 static void* config_loader(void *arg) {
690 typedef set<CONFIG *> configp_set;
691 configp_set old_configs;
692 while (true) {
693 sleep(180); // look for modifications every 3 minutes
694 CONFIG &dc = *config;
695 time_t then = dc.load_time;
696 struct stat st;
697 bool reload = false;
698 for (string_list::iterator i=dc.config_files.begin(); i!=dc.config_files.end(); i++) {
699 char *fn = *i;
700 if (stat(fn, &st)) reload = true; // file disappeared
701 else if (st.st_mtime > then) reload = true; // file modified
702 if (reload) break;
703 }
704 if (reload) {
705 CONFIG *newc = new_conf();
706 // replace the global config pointer
707 pthread_mutex_lock(&config_mutex);
708 CONFIG *old = config;
709 config = newc;
710 pthread_mutex_unlock(&config_mutex);
711 // dumpit(env_from);
712 // dumpit("envelope to dnsbl", env_to_dnsbl);
713 // dumpit("envelope to check from", env_to_chkfrom);
714 // dumpit();
715 if (old) old_configs.insert(old);
716 }
717 // now look for old configs with zero ref counts
718 for (configp_set::iterator i=old_configs.begin(); i!=old_configs.end(); ) {
719 CONFIG *old = *i;
720 if (!old->reference_count) {
721 delete old; // destructor does all the work
722 old_configs.erase(i++);
723 }
724 else i++;
725 }
726 }
727 }
728
729
730 static void usage(char *prog);
731 static void usage(char *prog)
732 {
733 fprintf(stderr, "Usage: %s -p socket-addr [-t timeout]\n", prog);
734 fprintf(stderr, "where socket-addr is for the connection to sendmail and should be one of\n");
735 fprintf(stderr, " inet:port@local-ip-address\n");
736 fprintf(stderr, " local:local-domain-socket-file-name\n");
737 }
738
739
740 int main(int argc, char**argv)
741 {
742 bool setconn = FALSE;
743 int c;
744 const char *args = "p:s:h";
745 extern char *optarg;
746
747 // Process command line options
748 while ((c = getopt(argc, argv, args)) != -1) {
749 switch (c) {
750 case 'p':
751 if (optarg == NULL || *optarg == '\0') {
752 fprintf(stderr, "Illegal conn: %s\n", optarg);
753 exit(EX_USAGE);
754 }
755 if (smfi_setconn(optarg) == MI_FAILURE) {
756 fprintf(stderr, "smfi_setconn failed\n");
757 exit(EX_SOFTWARE);
758 }
759
760 if (strncasecmp(optarg, "unix:", 5) == 0) unlink(optarg + 5);
761 else if (strncasecmp(optarg, "local:", 6) == 0) unlink(optarg + 6);
762 setconn = TRUE;
763 break;
764
765 case 't':
766 if (optarg == NULL || *optarg == '\0') {
767 fprintf(stderr, "Illegal timeout: %s\n", optarg);
768 exit(EX_USAGE);
769 }
770 if (smfi_settimeout(atoi(optarg)) == MI_FAILURE) {
771 fprintf(stderr, "smfi_settimeout failed\n");
772 exit(EX_SOFTWARE);
773 }
774 break;
775
776 case 'h':
777 default:
778 usage(argv[0]);
779 exit(EX_USAGE);
780 }
781 }
782 if (!setconn) {
783 fprintf(stderr, "%s: Missing required -p argument\n", argv[0]);
784 usage(argv[0]);
785 exit(EX_USAGE);
786 }
787 if (smfi_register(smfilter) == MI_FAILURE) {
788 fprintf(stderr, "smfi_register failed\n");
789 exit(EX_UNAVAILABLE);
790 }
791
792 // switch to background mode
793 if (daemon(1,0) < 0) {
794 fprintf(stderr, "daemon() call failed\n");
795 exit(EX_UNAVAILABLE);
796 }
797
798 // initialize the thread sync objects
799 pthread_mutex_init(&config_mutex, 0);
800 pthread_mutex_init(&syslog_mutex, 0);
801 pthread_mutex_init(&resolve_mutex, 0);
802
803 // load the initial config
804 config = new_conf();
805
806 // only create threads after the fork() in daemon
807 pthread_t tid;
808 if (pthread_create(&tid, 0, config_loader, 0))
809 my_syslog("failed to create config loader thread");
810 if (pthread_detach(tid))
811 my_syslog("failed to detach config loader thread");
812
813 // write the pid
814 const char *pidpath = "/var/run/dnsbl.pid";
815 unlink(pidpath);
816 FILE *f = fopen(pidpath, "w");
817 if (f) {
818 fprintf(f, "-%d\n", (u_int)getpgrp());
819 fclose(f);
820 }
821
822 int rc = smfi_main();
823 }