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/un.h>
54 #include <sys/select.h>
56 /* some systems (e.g. Darwin) seem to not define UNIX_PATH_MAX at all */
57 #ifndef UNIX_PATH_MAX
58 # define UNIX_PATH_MAX sizeof (((struct sockaddr_un *)0)->sun_path)
59 #endif /* UNIX_PATH_MAX */
61 #if HAVE_GRP_H
62 # include <grp.h>
63 #endif /* HAVE_GRP_H */
65 #define SOCK_PATH LOCALSTATEDIR"/run/"PACKAGE_NAME"-email"
66 #define MAX_CONNS 5
67 #define MAX_CONNS_LIMIT 16384
69 #define log_debug(...) DEBUG ("email: "__VA_ARGS__)
70 #define log_err(...) ERROR ("email: "__VA_ARGS__)
71 #define log_warn(...) WARNING ("email: "__VA_ARGS__)
73 /*
74 * Private data structures
75 */
76 /* linked list of email and check types */
77 typedef struct type {
78 char *name;
79 int value;
80 struct type *next;
81 } type_t;
83 typedef struct {
84 type_t *head;
85 type_t *tail;
86 } type_list_t;
88 /* collector thread control information */
89 typedef struct collector {
90 pthread_t thread;
92 /* socket descriptor of the current/last connection */
93 FILE *socket;
94 } collector_t;
96 /* linked list of pending connections */
97 typedef struct conn {
98 /* socket to read data from */
99 FILE *socket;
101 /* linked list of connections */
102 struct conn *next;
103 } conn_t;
105 typedef struct {
106 conn_t *head;
107 conn_t *tail;
108 } conn_list_t;
110 /*
111 * Private variables
112 */
113 /* valid configuration file keys */
114 static const char *config_keys[] =
115 {
116 "SocketFile",
117 "SocketGroup",
118 "SocketPerms",
119 "MaxConns"
120 };
121 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
123 /* socket configuration */
124 static char *sock_file = NULL;
125 static char *sock_group = NULL;
126 static int sock_perms = S_IRWXU | S_IRWXG;
127 static int max_conns = MAX_CONNS;
129 /* state of the plugin */
130 static int disabled = 0;
132 /* thread managing "client" connections */
133 static pthread_t connector = (pthread_t) 0;
134 static int connector_socket = -1;
136 /* tell the collector threads that a new connection is available */
137 static pthread_cond_t conn_available = PTHREAD_COND_INITIALIZER;
139 /* connections that are waiting to be processed */
140 static pthread_mutex_t conns_mutex = PTHREAD_MUTEX_INITIALIZER;
141 static conn_list_t conns;
143 /* tell the connector thread that a collector is available */
144 static pthread_cond_t collector_available = PTHREAD_COND_INITIALIZER;
146 /* collector threads */
147 static collector_t **collectors = NULL;
149 static pthread_mutex_t available_mutex = PTHREAD_MUTEX_INITIALIZER;
150 static int available_collectors;
152 static pthread_mutex_t count_mutex = PTHREAD_MUTEX_INITIALIZER;
153 static type_list_t list_count;
154 static type_list_t list_count_copy;
156 static pthread_mutex_t size_mutex = PTHREAD_MUTEX_INITIALIZER;
157 static type_list_t list_size;
158 static type_list_t list_size_copy;
160 static pthread_mutex_t score_mutex = PTHREAD_MUTEX_INITIALIZER;
161 static double score;
162 static int score_count;
164 static pthread_mutex_t check_mutex = PTHREAD_MUTEX_INITIALIZER;
165 static type_list_t list_check;
166 static type_list_t list_check_copy;
168 /*
169 * Private functions
170 */
171 static int email_config (const char *key, const char *value)
172 {
173 if (0 == strcasecmp (key, "SocketFile")) {
174 if (NULL != sock_file)
175 free (sock_file);
176 sock_file = sstrdup (value);
177 }
178 else if (0 == strcasecmp (key, "SocketGroup")) {
179 if (NULL != sock_group)
180 free (sock_group);
181 sock_group = sstrdup (value);
182 }
183 else if (0 == strcasecmp (key, "SocketPerms")) {
184 /* the user is responsible for providing reasonable values */
185 sock_perms = (int)strtol (value, NULL, 8);
186 }
187 else if (0 == strcasecmp (key, "MaxConns")) {
188 long int tmp = strtol (value, NULL, 0);
190 if (tmp < 1) {
191 fprintf (stderr, "email plugin: `MaxConns' was set to invalid "
192 "value %li, will use default %i.\n",
193 tmp, MAX_CONNS);
194 ERROR ("email plugin: `MaxConns' was set to invalid "
195 "value %li, will use default %i.\n",
196 tmp, MAX_CONNS);
197 max_conns = MAX_CONNS;
198 }
199 else if (tmp > MAX_CONNS_LIMIT) {
200 fprintf (stderr, "email plugin: `MaxConns' was set to invalid "
201 "value %li, will use hardcoded limit %i.\n",
202 tmp, MAX_CONNS_LIMIT);
203 ERROR ("email plugin: `MaxConns' was set to invalid "
204 "value %li, will use hardcoded limit %i.\n",
205 tmp, MAX_CONNS_LIMIT);
206 max_conns = MAX_CONNS_LIMIT;
207 }
208 else {
209 max_conns = (int)tmp;
210 }
211 }
212 else {
213 return -1;
214 }
215 return 0;
216 } /* static int email_config (char *, char *) */
218 /* Increment the value of the given name in the given list by incr. */
219 static void type_list_incr (type_list_t *list, char *name, int incr)
220 {
221 if (NULL == list->head) {
222 list->head = (type_t *)smalloc (sizeof (type_t));
224 list->head->name = sstrdup (name);
225 list->head->value = incr;
226 list->head->next = NULL;
228 list->tail = list->head;
229 }
230 else {
231 type_t *ptr;
233 for (ptr = list->head; NULL != ptr; ptr = ptr->next) {
234 if (0 == strcmp (name, ptr->name))
235 break;
236 }
238 if (NULL == ptr) {
239 list->tail->next = (type_t *)smalloc (sizeof (type_t));
240 list->tail = list->tail->next;
242 list->tail->name = sstrdup (name);
243 list->tail->value = incr;
244 list->tail->next = NULL;
245 }
246 else {
247 ptr->value += incr;
248 }
249 }
250 return;
251 } /* static void type_list_incr (type_list_t *, char *) */
253 static void *collect (void *arg)
254 {
255 collector_t *this = (collector_t *)arg;
257 while (1) {
258 conn_t *connection;
260 pthread_mutex_lock (&conns_mutex);
262 while (NULL == conns.head) {
263 pthread_cond_wait (&conn_available, &conns_mutex);
264 }
266 connection = conns.head;
267 conns.head = conns.head->next;
269 if (NULL == conns.head) {
270 conns.tail = NULL;
271 }
273 pthread_mutex_unlock (&conns_mutex);
275 /* make the socket available to the global
276 * thread and connection management */
277 this->socket = connection->socket;
279 log_debug ("collect: handling connection on fd #%i",
280 fileno (this->socket));
282 while (42) {
283 /* 256 bytes ought to be enough for anybody ;-) */
284 char line[256 + 1]; /* line + '\0' */
285 int len = 0;
287 errno = 0;
288 if (NULL == fgets (line, sizeof (line), this->socket)) {
289 if (0 != errno) {
290 char errbuf[1024];
291 log_err ("collect: reading from socket (fd #%i) "
292 "failed: %s", fileno (this->socket),
293 sstrerror (errno, errbuf, sizeof (errbuf)));
294 }
295 break;
296 }
298 len = strlen (line);
299 if (('\n' != line[len - 1]) && ('\r' != line[len - 1])) {
300 log_warn ("collect: line too long (> %zu characters): "
301 "'%s' (truncated)", sizeof (line) - 1, line);
303 while (NULL != fgets (line, sizeof (line), this->socket))
304 if (('\n' == line[len - 1]) || ('\r' == line[len - 1]))
305 break;
306 continue;
307 }
309 line[len - 1] = '\0';
311 log_debug ("collect: line = '%s'", line);
313 if (':' != line[1]) {
314 log_err ("collect: syntax error in line '%s'", line);
315 continue;
316 }
318 if ('e' == line[0]) { /* e:<type>:<bytes> */
319 char *ptr = NULL;
320 char *type = strtok_r (line + 2, ":", &ptr);
321 char *tmp = strtok_r (NULL, ":", &ptr);
322 int bytes = 0;
324 if (NULL == tmp) {
325 log_err ("collect: syntax error in line '%s'", line);
326 continue;
327 }
329 bytes = atoi (tmp);
331 pthread_mutex_lock (&count_mutex);
332 type_list_incr (&list_count, type, 1);
333 pthread_mutex_unlock (&count_mutex);
335 if (bytes > 0) {
336 pthread_mutex_lock (&size_mutex);
337 type_list_incr (&list_size, type, bytes);
338 pthread_mutex_unlock (&size_mutex);
339 }
340 }
341 else if ('s' == line[0]) { /* s:<value> */
342 pthread_mutex_lock (&score_mutex);
343 score = (score * (double)score_count + atof (line + 2))
344 / (double)(score_count + 1);
345 ++score_count;
346 pthread_mutex_unlock (&score_mutex);
347 }
348 else if ('c' == line[0]) { /* c:<type1>[,<type2>,...] */
349 char *ptr = NULL;
350 char *type = strtok_r (line + 2, ",", &ptr);
352 do {
353 pthread_mutex_lock (&check_mutex);
354 type_list_incr (&list_check, type, 1);
355 pthread_mutex_unlock (&check_mutex);
356 } while (NULL != (type = strtok_r (NULL, ",", &ptr)));
357 }
358 else {
359 log_err ("collect: unknown type '%c'", line[0]);
360 }
361 } /* while (42) */
363 log_debug ("Shutting down connection on fd #%i",
364 fileno (this->socket));
366 fclose (connection->socket);
367 free (connection);
369 this->socket = NULL;
371 pthread_mutex_lock (&available_mutex);
372 ++available_collectors;
373 pthread_mutex_unlock (&available_mutex);
375 pthread_cond_signal (&collector_available);
376 } /* while (1) */
378 pthread_exit ((void *)0);
379 return ((void *) 0);
380 } /* static void *collect (void *) */
382 static void *open_connection (void __attribute__((unused)) *arg)
383 {
384 struct sockaddr_un addr;
386 char *path = (NULL == sock_file) ? SOCK_PATH : sock_file;
387 char *group = (NULL == sock_group) ? COLLECTD_GRP_NAME : sock_group;
389 /* create UNIX socket */
390 errno = 0;
391 if (-1 == (connector_socket = socket (PF_UNIX, SOCK_STREAM, 0))) {
392 char errbuf[1024];
393 disabled = 1;
394 log_err ("socket() failed: %s",
395 sstrerror (errno, errbuf, sizeof (errbuf)));
396 pthread_exit ((void *)1);
397 }
399 addr.sun_family = AF_UNIX;
400 sstrncpy (addr.sun_path, path, (size_t)(UNIX_PATH_MAX - 1));
402 errno = 0;
403 if (-1 == bind (connector_socket, (struct sockaddr *)&addr,
404 offsetof (struct sockaddr_un, sun_path)
405 + strlen(addr.sun_path))) {
406 char errbuf[1024];
407 disabled = 1;
408 close (connector_socket);
409 connector_socket = -1;
410 log_err ("bind() failed: %s",
411 sstrerror (errno, errbuf, sizeof (errbuf)));
412 pthread_exit ((void *)1);
413 }
415 errno = 0;
416 if (-1 == listen (connector_socket, 5)) {
417 char errbuf[1024];
418 disabled = 1;
419 close (connector_socket);
420 connector_socket = -1;
421 log_err ("listen() failed: %s",
422 sstrerror (errno, errbuf, sizeof (errbuf)));
423 pthread_exit ((void *)1);
424 }
426 {
427 struct group sg;
428 struct group *grp;
429 char grbuf[2048];
430 int status;
432 grp = NULL;
433 status = getgrnam_r (group, &sg, grbuf, sizeof (grbuf), &grp);
434 if (status != 0)
435 {
436 char errbuf[1024];
437 log_warn ("getgrnam_r (%s) failed: %s", group,
438 sstrerror (errno, errbuf, sizeof (errbuf)));
439 }
440 else if (grp == NULL)
441 {
442 log_warn ("No such group: `%s'", group);
443 }
444 else
445 {
446 status = chown (path, (uid_t) -1, grp->gr_gid);
447 if (status != 0)
448 {
449 char errbuf[1024];
450 log_warn ("chown (%s, -1, %i) failed: %s",
451 path, (int) grp->gr_gid,
452 sstrerror (errno, errbuf, sizeof (errbuf)));
453 }
454 }
455 }
457 errno = 0;
458 if (0 != chmod (path, sock_perms)) {
459 char errbuf[1024];
460 log_warn ("chmod() failed: %s",
461 sstrerror (errno, errbuf, sizeof (errbuf)));
462 }
464 { /* initialize collector threads */
465 int i = 0;
466 int err = 0;
468 pthread_attr_t ptattr;
470 conns.head = NULL;
471 conns.tail = NULL;
473 pthread_attr_init (&ptattr);
474 pthread_attr_setdetachstate (&ptattr, PTHREAD_CREATE_DETACHED);
476 available_collectors = max_conns;
478 collectors =
479 (collector_t **)smalloc (max_conns * sizeof (collector_t *));
481 for (i = 0; i < max_conns; ++i) {
482 collectors[i] = (collector_t *)smalloc (sizeof (collector_t));
483 collectors[i]->socket = NULL;
485 if (0 != (err = plugin_thread_create (&collectors[i]->thread,
486 &ptattr, collect, collectors[i]))) {
487 char errbuf[1024];
488 log_err ("pthread_create() failed: %s",
489 sstrerror (errno, errbuf, sizeof (errbuf)));
490 collectors[i]->thread = (pthread_t) 0;
491 }
492 }
494 pthread_attr_destroy (&ptattr);
495 }
497 while (1) {
498 int remote = 0;
500 conn_t *connection;
502 pthread_mutex_lock (&available_mutex);
504 while (0 == available_collectors) {
505 pthread_cond_wait (&collector_available, &available_mutex);
506 }
508 --available_collectors;
510 pthread_mutex_unlock (&available_mutex);
512 do {
513 errno = 0;
514 if (-1 == (remote = accept (connector_socket, NULL, NULL))) {
515 if (EINTR != errno) {
516 char errbuf[1024];
517 disabled = 1;
518 close (connector_socket);
519 connector_socket = -1;
520 log_err ("accept() failed: %s",
521 sstrerror (errno, errbuf, sizeof (errbuf)));
522 pthread_exit ((void *)1);
523 }
524 }
525 } while (EINTR == errno);
527 connection = (conn_t *)smalloc (sizeof (conn_t));
529 connection->socket = fdopen (remote, "r");
530 connection->next = NULL;
532 if (NULL == connection->socket) {
533 close (remote);
534 continue;
535 }
537 pthread_mutex_lock (&conns_mutex);
539 if (NULL == conns.head) {
540 conns.head = connection;
541 conns.tail = connection;
542 }
543 else {
544 conns.tail->next = connection;
545 conns.tail = conns.tail->next;
546 }
548 pthread_mutex_unlock (&conns_mutex);
550 pthread_cond_signal (&conn_available);
551 }
553 pthread_exit ((void *) 0);
554 return ((void *) 0);
555 } /* static void *open_connection (void *) */
557 static int email_init (void)
558 {
559 int err = 0;
561 if (0 != (err = plugin_thread_create (&connector, NULL,
562 open_connection, NULL))) {
563 char errbuf[1024];
564 disabled = 1;
565 log_err ("pthread_create() failed: %s",
566 sstrerror (errno, errbuf, sizeof (errbuf)));
567 return (-1);
568 }
570 return (0);
571 } /* int email_init */
573 static void type_list_free (type_list_t *t)
574 {
575 type_t *this;
577 this = t->head;
578 while (this != NULL)
579 {
580 type_t *next = this->next;
582 sfree (this->name);
583 sfree (this);
585 this = next;
586 }
588 t->head = NULL;
589 t->tail = NULL;
590 }
592 static int email_shutdown (void)
593 {
594 int i = 0;
596 if (connector != ((pthread_t) 0)) {
597 pthread_kill (connector, SIGTERM);
598 connector = (pthread_t) 0;
599 }
601 if (connector_socket >= 0) {
602 close (connector_socket);
603 connector_socket = -1;
604 }
606 /* don't allow any more connections to be processed */
607 pthread_mutex_lock (&conns_mutex);
609 available_collectors = 0;
611 if (collectors != NULL) {
612 for (i = 0; i < max_conns; ++i) {
613 if (collectors[i] == NULL)
614 continue;
616 if (collectors[i]->thread != ((pthread_t) 0)) {
617 pthread_kill (collectors[i]->thread, SIGTERM);
618 collectors[i]->thread = (pthread_t) 0;
619 }
621 if (collectors[i]->socket != NULL) {
622 fclose (collectors[i]->socket);
623 collectors[i]->socket = NULL;
624 }
626 sfree (collectors[i]);
627 }
628 sfree (collectors);
629 } /* if (collectors != NULL) */
631 pthread_mutex_unlock (&conns_mutex);
633 type_list_free (&list_count);
634 type_list_free (&list_count_copy);
635 type_list_free (&list_size);
636 type_list_free (&list_size_copy);
637 type_list_free (&list_check);
638 type_list_free (&list_check_copy);
640 unlink ((NULL == sock_file) ? SOCK_PATH : sock_file);
642 sfree (sock_file);
643 sfree (sock_group);
644 return (0);
645 } /* static void email_shutdown (void) */
647 static void email_submit (const char *type, const char *type_instance, gauge_t value)
648 {
649 value_t values[1];
650 value_list_t vl = VALUE_LIST_INIT;
652 values[0].gauge = value;
654 vl.values = values;
655 vl.values_len = 1;
656 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
657 sstrncpy (vl.plugin, "email", sizeof (vl.plugin));
658 sstrncpy (vl.type, type, sizeof (vl.type));
659 sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
661 plugin_dispatch_values (&vl);
662 } /* void email_submit */
664 /* Copy list l1 to list l2. l2 may partly exist already, but it is assumed
665 * that neither the order nor the name of any element of either list is
666 * changed and no elements are deleted. The values of l1 are reset to zero
667 * after they have been copied to l2. */
668 static void copy_type_list (type_list_t *l1, type_list_t *l2)
669 {
670 type_t *ptr1;
671 type_t *ptr2;
673 type_t *last = NULL;
675 for (ptr1 = l1->head, ptr2 = l2->head; NULL != ptr1;
676 ptr1 = ptr1->next, last = ptr2, ptr2 = ptr2->next) {
677 if (NULL == ptr2) {
678 ptr2 = (type_t *)smalloc (sizeof (type_t));
679 ptr2->name = NULL;
680 ptr2->next = NULL;
682 if (NULL == last) {
683 l2->head = ptr2;
684 }
685 else {
686 last->next = ptr2;
687 }
689 l2->tail = ptr2;
690 }
692 if (NULL == ptr2->name) {
693 ptr2->name = sstrdup (ptr1->name);
694 }
696 ptr2->value = ptr1->value;
697 ptr1->value = 0;
698 }
699 return;
700 }
702 static int email_read (void)
703 {
704 type_t *ptr;
706 double score_old;
707 int score_count_old;
709 if (disabled)
710 return (-1);
712 /* email count */
713 pthread_mutex_lock (&count_mutex);
715 copy_type_list (&list_count, &list_count_copy);
717 pthread_mutex_unlock (&count_mutex);
719 for (ptr = list_count_copy.head; NULL != ptr; ptr = ptr->next) {
720 email_submit ("email_count", ptr->name, ptr->value);
721 }
723 /* email size */
724 pthread_mutex_lock (&size_mutex);
726 copy_type_list (&list_size, &list_size_copy);
728 pthread_mutex_unlock (&size_mutex);
730 for (ptr = list_size_copy.head; NULL != ptr; ptr = ptr->next) {
731 email_submit ("email_size", ptr->name, ptr->value);
732 }
734 /* spam score */
735 pthread_mutex_lock (&score_mutex);
737 score_old = score;
738 score_count_old = score_count;
739 score = 0.0;
740 score_count = 0;
742 pthread_mutex_unlock (&score_mutex);
744 if (score_count_old > 0)
745 email_submit ("spam_score", "", score_old);
747 /* spam checks */
748 pthread_mutex_lock (&check_mutex);
750 copy_type_list (&list_check, &list_check_copy);
752 pthread_mutex_unlock (&check_mutex);
754 for (ptr = list_check_copy.head; NULL != ptr; ptr = ptr->next)
755 email_submit ("spam_check", ptr->name, ptr->value);
757 return (0);
758 } /* int email_read */
760 void module_register (void)
761 {
762 plugin_register_config ("email", email_config, config_keys, config_keys_num);
763 plugin_register_init ("email", email_init);
764 plugin_register_read ("email", email_read);
765 plugin_register_shutdown ("email", email_shutdown);
766 } /* void module_register */
768 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */