1 /**
2 * collectd - src/email.c
3 * Copyright (C) 2006-2008 Sebastian Harl
4 *
5 * Permission is hereby granted, free of charge, to any person obtaining a
6 * copy of this software and associated documentation files (the "Software"),
7 * to deal in the Software without restriction, including without limitation
8 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
9 * and/or sell copies of the Software, and to permit persons to whom the
10 * Software is furnished to do so, subject to the following conditions:
11 *
12 * The above copyright notice and this permission notice shall be included in
13 * all copies or substantial portions of the Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
21 * DEALINGS IN THE SOFTWARE.
22 *
23 * Authors:
24 * Sebastian Harl <sh at tokkee.org>
25 **/
27 /*
28 * This plugin communicates with a spam filter, a virus scanner or similar
29 * software using a UNIX socket and a very simple protocol:
30 *
31 * e-mail type (e.g. ham, spam, virus, ...) and size
32 * e:<type>:<bytes>
33 *
34 * spam score
35 * s:<value>
36 *
37 * successful spam checks
38 * c:<type1>[,<type2>,...]
39 */
41 #include "collectd.h"
42 #include "common.h"
43 #include "plugin.h"
45 #include "configfile.h"
47 #include <stddef.h>
49 #if HAVE_LIBPTHREAD
50 # include <pthread.h>
51 #endif
53 #include <sys/socket.h>
54 #include <sys/un.h>
55 #include <sys/select.h>
57 /* some systems (e.g. Darwin) seem to not define UNIX_PATH_MAX at all */
58 #ifndef UNIX_PATH_MAX
59 # define UNIX_PATH_MAX sizeof (((struct sockaddr_un *)0)->sun_path)
60 #endif /* UNIX_PATH_MAX */
62 #if HAVE_GRP_H
63 # include <grp.h>
64 #endif /* HAVE_GRP_H */
66 #define SOCK_PATH LOCALSTATEDIR"/run/"PACKAGE_NAME"-email"
67 #define MAX_CONNS 5
68 #define MAX_CONNS_LIMIT 16384
70 #define log_debug(...) DEBUG ("email: "__VA_ARGS__)
71 #define log_err(...) ERROR ("email: "__VA_ARGS__)
72 #define log_warn(...) WARNING ("email: "__VA_ARGS__)
74 /*
75 * Private data structures
76 */
77 /* linked list of email and check types */
78 typedef struct type {
79 char *name;
80 int value;
81 struct type *next;
82 } type_t;
84 typedef struct {
85 type_t *head;
86 type_t *tail;
87 } type_list_t;
89 /* collector thread control information */
90 typedef struct collector {
91 pthread_t thread;
93 /* socket descriptor of the current/last connection */
94 FILE *socket;
95 } collector_t;
97 /* linked list of pending connections */
98 typedef struct conn {
99 /* socket to read data from */
100 FILE *socket;
102 /* linked list of connections */
103 struct conn *next;
104 } conn_t;
106 typedef struct {
107 conn_t *head;
108 conn_t *tail;
109 } conn_list_t;
111 /*
112 * Private variables
113 */
114 /* valid configuration file keys */
115 static const char *config_keys[] =
116 {
117 "SocketFile",
118 "SocketGroup",
119 "SocketPerms",
120 "MaxConns"
121 };
122 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
124 /* socket configuration */
125 static char *sock_file = NULL;
126 static char *sock_group = NULL;
127 static int sock_perms = S_IRWXU | S_IRWXG;
128 static int max_conns = MAX_CONNS;
130 /* state of the plugin */
131 static int disabled = 0;
133 /* thread managing "client" connections */
134 static pthread_t connector = (pthread_t) 0;
135 static int connector_socket = -1;
137 /* tell the collector threads that a new connection is available */
138 static pthread_cond_t conn_available = PTHREAD_COND_INITIALIZER;
140 /* connections that are waiting to be processed */
141 static pthread_mutex_t conns_mutex = PTHREAD_MUTEX_INITIALIZER;
142 static conn_list_t conns;
144 /* tell the connector thread that a collector is available */
145 static pthread_cond_t collector_available = PTHREAD_COND_INITIALIZER;
147 /* collector threads */
148 static collector_t **collectors = NULL;
150 static pthread_mutex_t available_mutex = PTHREAD_MUTEX_INITIALIZER;
151 static int available_collectors;
153 static pthread_mutex_t count_mutex = PTHREAD_MUTEX_INITIALIZER;
154 static type_list_t list_count;
155 static type_list_t list_count_copy;
157 static pthread_mutex_t size_mutex = PTHREAD_MUTEX_INITIALIZER;
158 static type_list_t list_size;
159 static type_list_t list_size_copy;
161 static pthread_mutex_t score_mutex = PTHREAD_MUTEX_INITIALIZER;
162 static double score;
163 static int score_count;
165 static pthread_mutex_t check_mutex = PTHREAD_MUTEX_INITIALIZER;
166 static type_list_t list_check;
167 static type_list_t list_check_copy;
169 /*
170 * Private functions
171 */
172 static int email_config (const char *key, const char *value)
173 {
174 if (0 == strcasecmp (key, "SocketFile")) {
175 if (NULL != sock_file)
176 free (sock_file);
177 sock_file = sstrdup (value);
178 }
179 else if (0 == strcasecmp (key, "SocketGroup")) {
180 if (NULL != sock_group)
181 free (sock_group);
182 sock_group = sstrdup (value);
183 }
184 else if (0 == strcasecmp (key, "SocketPerms")) {
185 /* the user is responsible for providing reasonable values */
186 sock_perms = (int)strtol (value, NULL, 8);
187 }
188 else if (0 == strcasecmp (key, "MaxConns")) {
189 long int tmp = strtol (value, NULL, 0);
191 if (tmp < 1) {
192 fprintf (stderr, "email plugin: `MaxConns' was set to invalid "
193 "value %li, will use default %i.\n",
194 tmp, MAX_CONNS);
195 ERROR ("email plugin: `MaxConns' was set to invalid "
196 "value %li, will use default %i.\n",
197 tmp, MAX_CONNS);
198 max_conns = MAX_CONNS;
199 }
200 else if (tmp > MAX_CONNS_LIMIT) {
201 fprintf (stderr, "email plugin: `MaxConns' was set to invalid "
202 "value %li, will use hardcoded limit %i.\n",
203 tmp, MAX_CONNS_LIMIT);
204 ERROR ("email plugin: `MaxConns' was set to invalid "
205 "value %li, will use hardcoded limit %i.\n",
206 tmp, MAX_CONNS_LIMIT);
207 max_conns = MAX_CONNS_LIMIT;
208 }
209 else {
210 max_conns = (int)tmp;
211 }
212 }
213 else {
214 return -1;
215 }
216 return 0;
217 } /* static int email_config (char *, char *) */
219 /* Increment the value of the given name in the given list by incr. */
220 static void type_list_incr (type_list_t *list, char *name, int incr)
221 {
222 if (NULL == list->head) {
223 list->head = (type_t *)smalloc (sizeof (type_t));
225 list->head->name = sstrdup (name);
226 list->head->value = incr;
227 list->head->next = NULL;
229 list->tail = list->head;
230 }
231 else {
232 type_t *ptr;
234 for (ptr = list->head; NULL != ptr; ptr = ptr->next) {
235 if (0 == strcmp (name, ptr->name))
236 break;
237 }
239 if (NULL == ptr) {
240 list->tail->next = (type_t *)smalloc (sizeof (type_t));
241 list->tail = list->tail->next;
243 list->tail->name = sstrdup (name);
244 list->tail->value = incr;
245 list->tail->next = NULL;
246 }
247 else {
248 ptr->value += incr;
249 }
250 }
251 return;
252 } /* static void type_list_incr (type_list_t *, char *) */
254 static void *collect (void *arg)
255 {
256 collector_t *this = (collector_t *)arg;
258 while (1) {
259 int loop = 1;
261 conn_t *connection;
263 pthread_mutex_lock (&conns_mutex);
265 while (NULL == conns.head) {
266 pthread_cond_wait (&conn_available, &conns_mutex);
267 }
269 connection = conns.head;
270 conns.head = conns.head->next;
272 if (NULL == conns.head) {
273 conns.tail = NULL;
274 }
276 pthread_mutex_unlock (&conns_mutex);
278 /* make the socket available to the global
279 * thread and connection management */
280 this->socket = connection->socket;
282 log_debug ("collect: handling connection on fd #%i",
283 fileno (this->socket));
285 while (loop) {
286 /* 256 bytes ought to be enough for anybody ;-) */
287 char line[256 + 1]; /* line + '\0' */
288 int len = 0;
290 errno = 0;
291 if (NULL == fgets (line, sizeof (line), this->socket)) {
292 loop = 0;
294 if (0 != errno) {
295 char errbuf[1024];
296 log_err ("collect: reading from socket (fd #%i) "
297 "failed: %s", fileno (this->socket),
298 sstrerror (errno, errbuf, sizeof (errbuf)));
299 }
300 break;
301 }
303 len = strlen (line);
304 if (('\n' != line[len - 1]) && ('\r' != line[len - 1])) {
305 log_warn ("collect: line too long (> %zu characters): "
306 "'%s' (truncated)", sizeof (line) - 1, line);
308 while (NULL != fgets (line, sizeof (line), this->socket))
309 if (('\n' == line[len - 1]) || ('\r' == line[len - 1]))
310 break;
311 continue;
312 }
314 line[len - 1] = '\0';
316 log_debug ("collect: line = '%s'", line);
318 if (':' != line[1]) {
319 log_err ("collect: syntax error in line '%s'", line);
320 continue;
321 }
323 if ('e' == line[0]) { /* e:<type>:<bytes> */
324 char *ptr = NULL;
325 char *type = strtok_r (line + 2, ":", &ptr);
326 char *tmp = strtok_r (NULL, ":", &ptr);
327 int bytes = 0;
329 if (NULL == tmp) {
330 log_err ("collect: syntax error in line '%s'", line);
331 continue;
332 }
334 bytes = atoi (tmp);
336 pthread_mutex_lock (&count_mutex);
337 type_list_incr (&list_count, type, 1);
338 pthread_mutex_unlock (&count_mutex);
340 if (bytes > 0) {
341 pthread_mutex_lock (&size_mutex);
342 type_list_incr (&list_size, type, bytes);
343 pthread_mutex_unlock (&size_mutex);
344 }
345 }
346 else if ('s' == line[0]) { /* s:<value> */
347 pthread_mutex_lock (&score_mutex);
348 score = (score * (double)score_count + atof (line + 2))
349 / (double)(score_count + 1);
350 ++score_count;
351 pthread_mutex_unlock (&score_mutex);
352 }
353 else if ('c' == line[0]) { /* c:<type1>[,<type2>,...] */
354 char *ptr = NULL;
355 char *type = strtok_r (line + 2, ",", &ptr);
357 do {
358 pthread_mutex_lock (&check_mutex);
359 type_list_incr (&list_check, type, 1);
360 pthread_mutex_unlock (&check_mutex);
361 } while (NULL != (type = strtok_r (NULL, ",", &ptr)));
362 }
363 else {
364 log_err ("collect: unknown type '%c'", line[0]);
365 }
366 } /* while (loop) */
368 log_debug ("Shutting down connection on fd #%i",
369 fileno (this->socket));
371 fclose (connection->socket);
372 free (connection);
374 this->socket = NULL;
376 pthread_mutex_lock (&available_mutex);
377 ++available_collectors;
378 pthread_mutex_unlock (&available_mutex);
380 pthread_cond_signal (&collector_available);
381 } /* while (1) */
383 pthread_exit ((void *)0);
384 return ((void *) 0);
385 } /* static void *collect (void *) */
387 static void *open_connection (void __attribute__((unused)) *arg)
388 {
389 struct sockaddr_un addr;
391 char *path = (NULL == sock_file) ? SOCK_PATH : sock_file;
392 char *group = (NULL == sock_group) ? COLLECTD_GRP_NAME : sock_group;
394 /* create UNIX socket */
395 errno = 0;
396 if (-1 == (connector_socket = socket (PF_UNIX, SOCK_STREAM, 0))) {
397 char errbuf[1024];
398 disabled = 1;
399 log_err ("socket() failed: %s",
400 sstrerror (errno, errbuf, sizeof (errbuf)));
401 pthread_exit ((void *)1);
402 }
404 addr.sun_family = AF_UNIX;
405 sstrncpy (addr.sun_path, path, (size_t)(UNIX_PATH_MAX - 1));
407 errno = 0;
408 if (-1 == bind (connector_socket, (struct sockaddr *)&addr,
409 offsetof (struct sockaddr_un, sun_path)
410 + strlen(addr.sun_path))) {
411 char errbuf[1024];
412 disabled = 1;
413 close (connector_socket);
414 connector_socket = -1;
415 log_err ("bind() failed: %s",
416 sstrerror (errno, errbuf, sizeof (errbuf)));
417 pthread_exit ((void *)1);
418 }
420 errno = 0;
421 if (-1 == listen (connector_socket, 5)) {
422 char errbuf[1024];
423 disabled = 1;
424 close (connector_socket);
425 connector_socket = -1;
426 log_err ("listen() failed: %s",
427 sstrerror (errno, errbuf, sizeof (errbuf)));
428 pthread_exit ((void *)1);
429 }
431 {
432 struct group sg;
433 struct group *grp;
434 char grbuf[2048];
435 int status;
437 grp = NULL;
438 status = getgrnam_r (group, &sg, grbuf, sizeof (grbuf), &grp);
439 if (status != 0)
440 {
441 char errbuf[1024];
442 log_warn ("getgrnam_r (%s) failed: %s", group,
443 sstrerror (errno, errbuf, sizeof (errbuf)));
444 }
445 else if (grp == NULL)
446 {
447 log_warn ("No such group: `%s'", group);
448 }
449 else
450 {
451 status = chown (path, (uid_t) -1, grp->gr_gid);
452 if (status != 0)
453 {
454 char errbuf[1024];
455 log_warn ("chown (%s, -1, %i) failed: %s",
456 path, (int) grp->gr_gid,
457 sstrerror (errno, errbuf, sizeof (errbuf)));
458 }
459 }
460 }
462 errno = 0;
463 if (0 != chmod (path, sock_perms)) {
464 char errbuf[1024];
465 log_warn ("chmod() failed: %s",
466 sstrerror (errno, errbuf, sizeof (errbuf)));
467 }
469 { /* initialize collector threads */
470 int i = 0;
471 int err = 0;
473 pthread_attr_t ptattr;
475 conns.head = NULL;
476 conns.tail = NULL;
478 pthread_attr_init (&ptattr);
479 pthread_attr_setdetachstate (&ptattr, PTHREAD_CREATE_DETACHED);
481 available_collectors = max_conns;
483 collectors =
484 (collector_t **)smalloc (max_conns * sizeof (collector_t *));
486 for (i = 0; i < max_conns; ++i) {
487 collectors[i] = (collector_t *)smalloc (sizeof (collector_t));
488 collectors[i]->socket = NULL;
490 if (0 != (err = plugin_thread_create (&collectors[i]->thread,
491 &ptattr, collect, collectors[i]))) {
492 char errbuf[1024];
493 log_err ("pthread_create() failed: %s",
494 sstrerror (errno, errbuf, sizeof (errbuf)));
495 collectors[i]->thread = (pthread_t) 0;
496 }
497 }
499 pthread_attr_destroy (&ptattr);
500 }
502 while (1) {
503 int remote = 0;
505 conn_t *connection;
507 pthread_mutex_lock (&available_mutex);
509 while (0 == available_collectors) {
510 pthread_cond_wait (&collector_available, &available_mutex);
511 }
513 --available_collectors;
515 pthread_mutex_unlock (&available_mutex);
517 do {
518 errno = 0;
519 if (-1 == (remote = accept (connector_socket, NULL, NULL))) {
520 if (EINTR != errno) {
521 char errbuf[1024];
522 disabled = 1;
523 close (connector_socket);
524 connector_socket = -1;
525 log_err ("accept() failed: %s",
526 sstrerror (errno, errbuf, sizeof (errbuf)));
527 pthread_exit ((void *)1);
528 }
529 }
530 } while (EINTR == errno);
532 connection = (conn_t *)smalloc (sizeof (conn_t));
534 connection->socket = fdopen (remote, "r");
535 connection->next = NULL;
537 if (NULL == connection->socket) {
538 close (remote);
539 continue;
540 }
542 pthread_mutex_lock (&conns_mutex);
544 if (NULL == conns.head) {
545 conns.head = connection;
546 conns.tail = connection;
547 }
548 else {
549 conns.tail->next = connection;
550 conns.tail = conns.tail->next;
551 }
553 pthread_mutex_unlock (&conns_mutex);
555 pthread_cond_signal (&conn_available);
556 }
558 pthread_exit ((void *) 0);
559 return ((void *) 0);
560 } /* static void *open_connection (void *) */
562 static int email_init (void)
563 {
564 int err = 0;
566 if (0 != (err = plugin_thread_create (&connector, NULL,
567 open_connection, NULL))) {
568 char errbuf[1024];
569 disabled = 1;
570 log_err ("pthread_create() failed: %s",
571 sstrerror (errno, errbuf, sizeof (errbuf)));
572 return (-1);
573 }
575 return (0);
576 } /* int email_init */
578 static int email_shutdown (void)
579 {
580 type_t *ptr = NULL;
582 int i = 0;
584 if (connector != ((pthread_t) 0)) {
585 pthread_kill (connector, SIGTERM);
586 connector = (pthread_t) 0;
587 }
589 if (connector_socket >= 0) {
590 close (connector_socket);
591 connector_socket = -1;
592 }
594 /* don't allow any more connections to be processed */
595 pthread_mutex_lock (&conns_mutex);
597 available_collectors = 0;
599 if (collectors != NULL) {
600 for (i = 0; i < max_conns; ++i) {
601 if (collectors[i] == NULL)
602 continue;
604 if (collectors[i]->thread != ((pthread_t) 0)) {
605 pthread_kill (collectors[i]->thread, SIGTERM);
606 collectors[i]->thread = (pthread_t) 0;
607 }
609 if (collectors[i]->socket != NULL) {
610 fclose (collectors[i]->socket);
611 collectors[i]->socket = NULL;
612 }
614 sfree (collectors[i]);
615 }
616 sfree (collectors);
617 } /* if (collectors != NULL) */
619 pthread_mutex_unlock (&conns_mutex);
621 for (ptr = list_count.head; NULL != ptr; ptr = ptr->next) {
622 free (ptr->name);
623 free (ptr);
624 }
626 for (ptr = list_count_copy.head; NULL != ptr; ptr = ptr->next) {
627 free (ptr->name);
628 free (ptr);
629 }
631 for (ptr = list_size.head; NULL != ptr; ptr = ptr->next) {
632 free (ptr->name);
633 free (ptr);
634 }
636 for (ptr = list_size_copy.head; NULL != ptr; ptr = ptr->next) {
637 free (ptr->name);
638 free (ptr);
639 }
641 for (ptr = list_check.head; NULL != ptr; ptr = ptr->next) {
642 free (ptr->name);
643 free (ptr);
644 }
646 for (ptr = list_check_copy.head; NULL != ptr; ptr = ptr->next) {
647 free (ptr->name);
648 free (ptr);
649 }
651 unlink ((NULL == sock_file) ? SOCK_PATH : sock_file);
653 sfree (sock_file);
654 sfree (sock_group);
655 return (0);
656 } /* static void email_shutdown (void) */
658 static void email_submit (const char *type, const char *type_instance, gauge_t value)
659 {
660 value_t values[1];
661 value_list_t vl = VALUE_LIST_INIT;
663 values[0].gauge = value;
665 vl.values = values;
666 vl.values_len = 1;
667 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
668 sstrncpy (vl.plugin, "email", sizeof (vl.plugin));
669 sstrncpy (vl.type, type, sizeof (vl.type));
670 sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
672 plugin_dispatch_values (&vl);
673 } /* void email_submit */
675 /* Copy list l1 to list l2. l2 may partly exist already, but it is assumed
676 * that neither the order nor the name of any element of either list is
677 * changed and no elements are deleted. The values of l1 are reset to zero
678 * after they have been copied to l2. */
679 static void copy_type_list (type_list_t *l1, type_list_t *l2)
680 {
681 type_t *ptr1;
682 type_t *ptr2;
684 type_t *last = NULL;
686 for (ptr1 = l1->head, ptr2 = l2->head; NULL != ptr1;
687 ptr1 = ptr1->next, last = ptr2, ptr2 = ptr2->next) {
688 if (NULL == ptr2) {
689 ptr2 = (type_t *)smalloc (sizeof (type_t));
690 ptr2->name = NULL;
691 ptr2->next = NULL;
693 if (NULL == last) {
694 l2->head = ptr2;
695 }
696 else {
697 last->next = ptr2;
698 }
700 l2->tail = ptr2;
701 }
703 if (NULL == ptr2->name) {
704 ptr2->name = sstrdup (ptr1->name);
705 }
707 ptr2->value = ptr1->value;
708 ptr1->value = 0;
709 }
710 return;
711 }
713 static int email_read (void)
714 {
715 type_t *ptr;
717 double score_old;
718 int score_count_old;
720 if (disabled)
721 return (-1);
723 /* email count */
724 pthread_mutex_lock (&count_mutex);
726 copy_type_list (&list_count, &list_count_copy);
728 pthread_mutex_unlock (&count_mutex);
730 for (ptr = list_count_copy.head; NULL != ptr; ptr = ptr->next) {
731 email_submit ("email_count", ptr->name, ptr->value);
732 }
734 /* email size */
735 pthread_mutex_lock (&size_mutex);
737 copy_type_list (&list_size, &list_size_copy);
739 pthread_mutex_unlock (&size_mutex);
741 for (ptr = list_size_copy.head; NULL != ptr; ptr = ptr->next) {
742 email_submit ("email_size", ptr->name, ptr->value);
743 }
745 /* spam score */
746 pthread_mutex_lock (&score_mutex);
748 score_old = score;
749 score_count_old = score_count;
750 score = 0.0;
751 score_count = 0;
753 pthread_mutex_unlock (&score_mutex);
755 if (score_count_old > 0)
756 email_submit ("spam_score", "", score_old);
758 /* spam checks */
759 pthread_mutex_lock (&check_mutex);
761 copy_type_list (&list_check, &list_check_copy);
763 pthread_mutex_unlock (&check_mutex);
765 for (ptr = list_check_copy.head; NULL != ptr; ptr = ptr->next)
766 email_submit ("spam_check", ptr->name, ptr->value);
768 return (0);
769 } /* int email_read */
771 void module_register (void)
772 {
773 plugin_register_config ("email", email_config, config_keys, config_keys_num);
774 plugin_register_init ("email", email_init);
775 plugin_register_read ("email", email_read);
776 plugin_register_shutdown ("email", email_shutdown);
777 } /* void module_register */
779 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */