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 conn_t *connection;
261 pthread_mutex_lock (&conns_mutex);
263 while (NULL == conns.head) {
264 pthread_cond_wait (&conn_available, &conns_mutex);
265 }
267 connection = conns.head;
268 conns.head = conns.head->next;
270 if (NULL == conns.head) {
271 conns.tail = NULL;
272 }
274 pthread_mutex_unlock (&conns_mutex);
276 /* make the socket available to the global
277 * thread and connection management */
278 this->socket = connection->socket;
280 log_debug ("collect: handling connection on fd #%i",
281 fileno (this->socket));
283 while (42) {
284 /* 256 bytes ought to be enough for anybody ;-) */
285 char line[256 + 1]; /* line + '\0' */
286 int len = 0;
288 errno = 0;
289 if (NULL == fgets (line, sizeof (line), this->socket)) {
290 if (0 != errno) {
291 char errbuf[1024];
292 log_err ("collect: reading from socket (fd #%i) "
293 "failed: %s", fileno (this->socket),
294 sstrerror (errno, errbuf, sizeof (errbuf)));
295 }
296 break;
297 }
299 len = strlen (line);
300 if (('\n' != line[len - 1]) && ('\r' != line[len - 1])) {
301 log_warn ("collect: line too long (> %zu characters): "
302 "'%s' (truncated)", sizeof (line) - 1, line);
304 while (NULL != fgets (line, sizeof (line), this->socket))
305 if (('\n' == line[len - 1]) || ('\r' == line[len - 1]))
306 break;
307 continue;
308 }
310 line[len - 1] = '\0';
312 log_debug ("collect: line = '%s'", line);
314 if (':' != line[1]) {
315 log_err ("collect: syntax error in line '%s'", line);
316 continue;
317 }
319 if ('e' == line[0]) { /* e:<type>:<bytes> */
320 char *ptr = NULL;
321 char *type = strtok_r (line + 2, ":", &ptr);
322 char *tmp = strtok_r (NULL, ":", &ptr);
323 int bytes = 0;
325 if (NULL == tmp) {
326 log_err ("collect: syntax error in line '%s'", line);
327 continue;
328 }
330 bytes = atoi (tmp);
332 pthread_mutex_lock (&count_mutex);
333 type_list_incr (&list_count, type, 1);
334 pthread_mutex_unlock (&count_mutex);
336 if (bytes > 0) {
337 pthread_mutex_lock (&size_mutex);
338 type_list_incr (&list_size, type, bytes);
339 pthread_mutex_unlock (&size_mutex);
340 }
341 }
342 else if ('s' == line[0]) { /* s:<value> */
343 pthread_mutex_lock (&score_mutex);
344 score = (score * (double)score_count + atof (line + 2))
345 / (double)(score_count + 1);
346 ++score_count;
347 pthread_mutex_unlock (&score_mutex);
348 }
349 else if ('c' == line[0]) { /* c:<type1>[,<type2>,...] */
350 char *ptr = NULL;
351 char *type = strtok_r (line + 2, ",", &ptr);
353 do {
354 pthread_mutex_lock (&check_mutex);
355 type_list_incr (&list_check, type, 1);
356 pthread_mutex_unlock (&check_mutex);
357 } while (NULL != (type = strtok_r (NULL, ",", &ptr)));
358 }
359 else {
360 log_err ("collect: unknown type '%c'", line[0]);
361 }
362 } /* while (42) */
364 log_debug ("Shutting down connection on fd #%i",
365 fileno (this->socket));
367 fclose (connection->socket);
368 free (connection);
370 this->socket = NULL;
372 pthread_mutex_lock (&available_mutex);
373 ++available_collectors;
374 pthread_mutex_unlock (&available_mutex);
376 pthread_cond_signal (&collector_available);
377 } /* while (1) */
379 pthread_exit ((void *)0);
380 return ((void *) 0);
381 } /* static void *collect (void *) */
383 static void *open_connection (void __attribute__((unused)) *arg)
384 {
385 struct sockaddr_un addr;
387 char *path = (NULL == sock_file) ? SOCK_PATH : sock_file;
388 char *group = (NULL == sock_group) ? COLLECTD_GRP_NAME : sock_group;
390 /* create UNIX socket */
391 errno = 0;
392 if (-1 == (connector_socket = socket (PF_UNIX, SOCK_STREAM, 0))) {
393 char errbuf[1024];
394 disabled = 1;
395 log_err ("socket() failed: %s",
396 sstrerror (errno, errbuf, sizeof (errbuf)));
397 pthread_exit ((void *)1);
398 }
400 addr.sun_family = AF_UNIX;
401 sstrncpy (addr.sun_path, path, (size_t)(UNIX_PATH_MAX - 1));
403 errno = 0;
404 if (-1 == bind (connector_socket, (struct sockaddr *)&addr,
405 offsetof (struct sockaddr_un, sun_path)
406 + strlen(addr.sun_path))) {
407 char errbuf[1024];
408 disabled = 1;
409 close (connector_socket);
410 connector_socket = -1;
411 log_err ("bind() failed: %s",
412 sstrerror (errno, errbuf, sizeof (errbuf)));
413 pthread_exit ((void *)1);
414 }
416 errno = 0;
417 if (-1 == listen (connector_socket, 5)) {
418 char errbuf[1024];
419 disabled = 1;
420 close (connector_socket);
421 connector_socket = -1;
422 log_err ("listen() failed: %s",
423 sstrerror (errno, errbuf, sizeof (errbuf)));
424 pthread_exit ((void *)1);
425 }
427 {
428 struct group sg;
429 struct group *grp;
430 char grbuf[2048];
431 int status;
433 grp = NULL;
434 status = getgrnam_r (group, &sg, grbuf, sizeof (grbuf), &grp);
435 if (status != 0)
436 {
437 char errbuf[1024];
438 log_warn ("getgrnam_r (%s) failed: %s", group,
439 sstrerror (errno, errbuf, sizeof (errbuf)));
440 }
441 else if (grp == NULL)
442 {
443 log_warn ("No such group: `%s'", group);
444 }
445 else
446 {
447 status = chown (path, (uid_t) -1, grp->gr_gid);
448 if (status != 0)
449 {
450 char errbuf[1024];
451 log_warn ("chown (%s, -1, %i) failed: %s",
452 path, (int) grp->gr_gid,
453 sstrerror (errno, errbuf, sizeof (errbuf)));
454 }
455 }
456 }
458 errno = 0;
459 if (0 != chmod (path, sock_perms)) {
460 char errbuf[1024];
461 log_warn ("chmod() failed: %s",
462 sstrerror (errno, errbuf, sizeof (errbuf)));
463 }
465 { /* initialize collector threads */
466 int i = 0;
467 int err = 0;
469 pthread_attr_t ptattr;
471 conns.head = NULL;
472 conns.tail = NULL;
474 pthread_attr_init (&ptattr);
475 pthread_attr_setdetachstate (&ptattr, PTHREAD_CREATE_DETACHED);
477 available_collectors = max_conns;
479 collectors =
480 (collector_t **)smalloc (max_conns * sizeof (collector_t *));
482 for (i = 0; i < max_conns; ++i) {
483 collectors[i] = (collector_t *)smalloc (sizeof (collector_t));
484 collectors[i]->socket = NULL;
486 if (0 != (err = plugin_thread_create (&collectors[i]->thread,
487 &ptattr, collect, collectors[i]))) {
488 char errbuf[1024];
489 log_err ("pthread_create() failed: %s",
490 sstrerror (errno, errbuf, sizeof (errbuf)));
491 collectors[i]->thread = (pthread_t) 0;
492 }
493 }
495 pthread_attr_destroy (&ptattr);
496 }
498 while (1) {
499 int remote = 0;
501 conn_t *connection;
503 pthread_mutex_lock (&available_mutex);
505 while (0 == available_collectors) {
506 pthread_cond_wait (&collector_available, &available_mutex);
507 }
509 --available_collectors;
511 pthread_mutex_unlock (&available_mutex);
513 do {
514 errno = 0;
515 if (-1 == (remote = accept (connector_socket, NULL, NULL))) {
516 if (EINTR != errno) {
517 char errbuf[1024];
518 disabled = 1;
519 close (connector_socket);
520 connector_socket = -1;
521 log_err ("accept() failed: %s",
522 sstrerror (errno, errbuf, sizeof (errbuf)));
523 pthread_exit ((void *)1);
524 }
525 }
526 } while (EINTR == errno);
528 connection = (conn_t *)smalloc (sizeof (conn_t));
530 connection->socket = fdopen (remote, "r");
531 connection->next = NULL;
533 if (NULL == connection->socket) {
534 close (remote);
535 continue;
536 }
538 pthread_mutex_lock (&conns_mutex);
540 if (NULL == conns.head) {
541 conns.head = connection;
542 conns.tail = connection;
543 }
544 else {
545 conns.tail->next = connection;
546 conns.tail = conns.tail->next;
547 }
549 pthread_mutex_unlock (&conns_mutex);
551 pthread_cond_signal (&conn_available);
552 }
554 pthread_exit ((void *) 0);
555 return ((void *) 0);
556 } /* static void *open_connection (void *) */
558 static int email_init (void)
559 {
560 int err = 0;
562 if (0 != (err = plugin_thread_create (&connector, NULL,
563 open_connection, NULL))) {
564 char errbuf[1024];
565 disabled = 1;
566 log_err ("pthread_create() failed: %s",
567 sstrerror (errno, errbuf, sizeof (errbuf)));
568 return (-1);
569 }
571 return (0);
572 } /* int email_init */
574 static void type_list_free (type_list_t *t)
575 {
576 type_t *this;
578 this = t->head;
579 while (this != NULL)
580 {
581 type_t *next = this->next;
583 sfree (this->name);
584 sfree (this);
586 this = next;
587 }
589 t->head = NULL;
590 t->tail = NULL;
591 }
593 static int email_shutdown (void)
594 {
595 int i = 0;
597 if (connector != ((pthread_t) 0)) {
598 pthread_kill (connector, SIGTERM);
599 connector = (pthread_t) 0;
600 }
602 if (connector_socket >= 0) {
603 close (connector_socket);
604 connector_socket = -1;
605 }
607 /* don't allow any more connections to be processed */
608 pthread_mutex_lock (&conns_mutex);
610 available_collectors = 0;
612 if (collectors != NULL) {
613 for (i = 0; i < max_conns; ++i) {
614 if (collectors[i] == NULL)
615 continue;
617 if (collectors[i]->thread != ((pthread_t) 0)) {
618 pthread_kill (collectors[i]->thread, SIGTERM);
619 collectors[i]->thread = (pthread_t) 0;
620 }
622 if (collectors[i]->socket != NULL) {
623 fclose (collectors[i]->socket);
624 collectors[i]->socket = NULL;
625 }
627 sfree (collectors[i]);
628 }
629 sfree (collectors);
630 } /* if (collectors != NULL) */
632 pthread_mutex_unlock (&conns_mutex);
634 type_list_free (&list_count);
635 type_list_free (&list_count_copy);
636 type_list_free (&list_size);
637 type_list_free (&list_size_copy);
638 type_list_free (&list_check);
639 type_list_free (&list_check_copy);
641 unlink ((NULL == sock_file) ? SOCK_PATH : sock_file);
643 sfree (sock_file);
644 sfree (sock_group);
645 return (0);
646 } /* static void email_shutdown (void) */
648 static void email_submit (const char *type, const char *type_instance, gauge_t value)
649 {
650 value_t values[1];
651 value_list_t vl = VALUE_LIST_INIT;
653 values[0].gauge = value;
655 vl.values = values;
656 vl.values_len = 1;
657 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
658 sstrncpy (vl.plugin, "email", sizeof (vl.plugin));
659 sstrncpy (vl.type, type, sizeof (vl.type));
660 sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
662 plugin_dispatch_values (&vl);
663 } /* void email_submit */
665 /* Copy list l1 to list l2. l2 may partly exist already, but it is assumed
666 * that neither the order nor the name of any element of either list is
667 * changed and no elements are deleted. The values of l1 are reset to zero
668 * after they have been copied to l2. */
669 static void copy_type_list (type_list_t *l1, type_list_t *l2)
670 {
671 type_t *ptr1;
672 type_t *ptr2;
674 type_t *last = NULL;
676 for (ptr1 = l1->head, ptr2 = l2->head; NULL != ptr1;
677 ptr1 = ptr1->next, last = ptr2, ptr2 = ptr2->next) {
678 if (NULL == ptr2) {
679 ptr2 = (type_t *)smalloc (sizeof (type_t));
680 ptr2->name = NULL;
681 ptr2->next = NULL;
683 if (NULL == last) {
684 l2->head = ptr2;
685 }
686 else {
687 last->next = ptr2;
688 }
690 l2->tail = ptr2;
691 }
693 if (NULL == ptr2->name) {
694 ptr2->name = sstrdup (ptr1->name);
695 }
697 ptr2->value = ptr1->value;
698 ptr1->value = 0;
699 }
700 return;
701 }
703 static int email_read (void)
704 {
705 type_t *ptr;
707 double score_old;
708 int score_count_old;
710 if (disabled)
711 return (-1);
713 /* email count */
714 pthread_mutex_lock (&count_mutex);
716 copy_type_list (&list_count, &list_count_copy);
718 pthread_mutex_unlock (&count_mutex);
720 for (ptr = list_count_copy.head; NULL != ptr; ptr = ptr->next) {
721 email_submit ("email_count", ptr->name, ptr->value);
722 }
724 /* email size */
725 pthread_mutex_lock (&size_mutex);
727 copy_type_list (&list_size, &list_size_copy);
729 pthread_mutex_unlock (&size_mutex);
731 for (ptr = list_size_copy.head; NULL != ptr; ptr = ptr->next) {
732 email_submit ("email_size", ptr->name, ptr->value);
733 }
735 /* spam score */
736 pthread_mutex_lock (&score_mutex);
738 score_old = score;
739 score_count_old = score_count;
740 score = 0.0;
741 score_count = 0;
743 pthread_mutex_unlock (&score_mutex);
745 if (score_count_old > 0)
746 email_submit ("spam_score", "", score_old);
748 /* spam checks */
749 pthread_mutex_lock (&check_mutex);
751 copy_type_list (&list_check, &list_check_copy);
753 pthread_mutex_unlock (&check_mutex);
755 for (ptr = list_check_copy.head; NULL != ptr; ptr = ptr->next)
756 email_submit ("spam_check", ptr->name, ptr->value);
758 return (0);
759 } /* int email_read */
761 void module_register (void)
762 {
763 plugin_register_config ("email", email_config, config_keys, config_keys_num);
764 plugin_register_init ("email", email_init);
765 plugin_register_read ("email", email_read);
766 plugin_register_shutdown ("email", email_shutdown);
767 } /* void module_register */
769 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */