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network: comment libgcrypt initalization process
[collectd.git] / src / email.c
1 /**
2  * collectd - src/email.c
3  * Copyright (C) 2006-2008  Sebastian Harl
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License as published by the
7  * Free Software Foundation; only version 2 of the License is applicable.
8  *
9  * This program is distributed in the hope that it will be useful, but
10  * WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
12  * General Public License for more details.
13  *
14  * You should have received a copy of the GNU General Public License along
15  * with this program; if not, write to the Free Software Foundation, Inc.,
16  * 51 Franklin St, Fifth Floor, Boston, MA  02110-1301 USA
17  *
18  * Author:
19  *   Sebastian Harl <sh at tokkee.org>
20  **/
22 /*
23  * This plugin communicates with a spam filter, a virus scanner or similar
24  * software using a UNIX socket and a very simple protocol:
25  *
26  * e-mail type (e.g. ham, spam, virus, ...) and size
27  * e:<type>:<bytes>
28  *
29  * spam score
30  * s:<value>
31  *
32  * successful spam checks
33  * c:<type1>[,<type2>,...]
34  */
36 #include "collectd.h"
37 #include "common.h"
38 #include "plugin.h"
40 #include "configfile.h"
42 #include <stddef.h>
44 #if HAVE_LIBPTHREAD
45 # include <pthread.h>
46 #endif
48 #include <sys/socket.h>
49 #include <sys/un.h>
50 #include <sys/select.h>
52 /* some systems (e.g. Darwin) seem to not define UNIX_PATH_MAX at all */
53 #ifndef UNIX_PATH_MAX
54 # define UNIX_PATH_MAX sizeof (((struct sockaddr_un *)0)->sun_path)
55 #endif /* UNIX_PATH_MAX */
57 #if HAVE_GRP_H
58 #       include <grp.h>
59 #endif /* HAVE_GRP_H */
61 #define SOCK_PATH LOCALSTATEDIR"/run/"PACKAGE_NAME"-email"
62 #define MAX_CONNS 5
63 #define MAX_CONNS_LIMIT 16384
65 #define log_debug(...) DEBUG ("email: "__VA_ARGS__)
66 #define log_err(...) ERROR ("email: "__VA_ARGS__)
67 #define log_warn(...) WARNING ("email: "__VA_ARGS__)
69 /*
70  * Private data structures
71  */
72 /* linked list of email and check types */
73 typedef struct type {
74         char        *name;
75         int         value;
76         struct type *next;
77 } type_t;
79 typedef struct {
80         type_t *head;
81         type_t *tail;
82 } type_list_t;
84 /* collector thread control information */
85 typedef struct collector {
86         pthread_t thread;
88         /* socket descriptor of the current/last connection */
89         FILE *socket;
90 } collector_t;
92 /* linked list of pending connections */
93 typedef struct conn {
94         /* socket to read data from */
95         FILE *socket;
97         /* linked list of connections */
98         struct conn *next;
99 } conn_t;
101 typedef struct {
102         conn_t *head;
103         conn_t *tail;
104 } conn_list_t;
106 /*
107  * Private variables
108  */
109 /* valid configuration file keys */
110 static const char *config_keys[] =
112         "SocketFile",
113         "SocketGroup",
114         "SocketPerms",
115         "MaxConns"
116 };
117 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
119 /* socket configuration */
120 static char *sock_file  = NULL;
121 static char *sock_group = NULL;
122 static int  sock_perms  = S_IRWXU | S_IRWXG;
123 static int  max_conns   = MAX_CONNS;
125 /* state of the plugin */
126 static int disabled = 0;
128 /* thread managing "client" connections */
129 static pthread_t connector = (pthread_t) 0;
130 static int connector_socket = -1;
132 /* tell the collector threads that a new connection is available */
133 static pthread_cond_t conn_available = PTHREAD_COND_INITIALIZER;
135 /* connections that are waiting to be processed */
136 static pthread_mutex_t conns_mutex = PTHREAD_MUTEX_INITIALIZER;
137 static conn_list_t conns;
139 /* tell the connector thread that a collector is available */
140 static pthread_cond_t collector_available = PTHREAD_COND_INITIALIZER;
142 /* collector threads */
143 static collector_t **collectors = NULL;
145 static pthread_mutex_t available_mutex = PTHREAD_MUTEX_INITIALIZER;
146 static int available_collectors;
148 static pthread_mutex_t count_mutex = PTHREAD_MUTEX_INITIALIZER;
149 static type_list_t list_count;
150 static type_list_t list_count_copy;
152 static pthread_mutex_t size_mutex = PTHREAD_MUTEX_INITIALIZER;
153 static type_list_t list_size;
154 static type_list_t list_size_copy;
156 static pthread_mutex_t score_mutex = PTHREAD_MUTEX_INITIALIZER;
157 static double score;
158 static int score_count;
160 static pthread_mutex_t check_mutex = PTHREAD_MUTEX_INITIALIZER;
161 static type_list_t list_check;
162 static type_list_t list_check_copy;
164 /*
165  * Private functions
166  */
167 static int email_config (const char *key, const char *value)
169         if (0 == strcasecmp (key, "SocketFile")) {
170                 if (NULL != sock_file)
171                         free (sock_file);
172                 sock_file = sstrdup (value);
173         }
174         else if (0 == strcasecmp (key, "SocketGroup")) {
175                 if (NULL != sock_group)
176                         free (sock_group);
177                 sock_group = sstrdup (value);
178         }
179         else if (0 == strcasecmp (key, "SocketPerms")) {
180                 /* the user is responsible for providing reasonable values */
181                 sock_perms = (int)strtol (value, NULL, 8);
182         }
183         else if (0 == strcasecmp (key, "MaxConns")) {
184                 long int tmp = strtol (value, NULL, 0);
186                 if (tmp < 1) {
187                         fprintf (stderr, "email plugin: `MaxConns' was set to invalid "
188                                         "value %li, will use default %i.\n",
189                                         tmp, MAX_CONNS);
190                         ERROR ("email plugin: `MaxConns' was set to invalid "
191                                         "value %li, will use default %i.\n",
192                                         tmp, MAX_CONNS);
193                         max_conns = MAX_CONNS;
194                 }
195                 else if (tmp > MAX_CONNS_LIMIT) {
196                         fprintf (stderr, "email plugin: `MaxConns' was set to invalid "
197                                         "value %li, will use hardcoded limit %i.\n",
198                                         tmp, MAX_CONNS_LIMIT);
199                         ERROR ("email plugin: `MaxConns' was set to invalid "
200                                         "value %li, will use hardcoded limit %i.\n",
201                                         tmp, MAX_CONNS_LIMIT);
202                         max_conns = MAX_CONNS_LIMIT;
203                 }
204                 else {
205                         max_conns = (int)tmp;
206                 }
207         }
208         else {
209                 return -1;
210         }
211         return 0;
212 } /* static int email_config (char *, char *) */
214 /* Increment the value of the given name in the given list by incr. */
215 static void type_list_incr (type_list_t *list, char *name, int incr)
217         if (NULL == list->head) {
218                 list->head = (type_t *)smalloc (sizeof (type_t));
220                 list->head->name  = sstrdup (name);
221                 list->head->value = incr;
222                 list->head->next  = NULL;
224                 list->tail = list->head;
225         }
226         else {
227                 type_t *ptr;
229                 for (ptr = list->head; NULL != ptr; ptr = ptr->next) {
230                         if (0 == strcmp (name, ptr->name))
231                                 break;
232                 }
234                 if (NULL == ptr) {
235                         list->tail->next = (type_t *)smalloc (sizeof (type_t));
236                         list->tail = list->tail->next;
238                         list->tail->name  = sstrdup (name);
239                         list->tail->value = incr;
240                         list->tail->next  = NULL;
241                 }
242                 else {
243                         ptr->value += incr;
244                 }
245         }
246         return;
247 } /* static void type_list_incr (type_list_t *, char *) */
249 static void *collect (void *arg)
251         collector_t *this = (collector_t *)arg;
253         while (1) {
254                 int loop = 1;
256                 conn_t *connection;
258                 pthread_mutex_lock (&conns_mutex);
260                 while (NULL == conns.head) {
261                         pthread_cond_wait (&conn_available, &conns_mutex);
262                 }
264                 connection = conns.head;
265                 conns.head = conns.head->next;
267                 if (NULL == conns.head) {
268                         conns.tail = NULL;
269                 }
271                 pthread_mutex_unlock (&conns_mutex);
273                 /* make the socket available to the global
274                  * thread and connection management */
275                 this->socket = connection->socket;
277                 log_debug ("collect: handling connection on fd #%i",
278                                 fileno (this->socket));
280                 while (loop) {
281                         /* 256 bytes ought to be enough for anybody ;-) */
282                         char line[256 + 1]; /* line + '\0' */
283                         int  len = 0;
285                         errno = 0;
286                         if (NULL == fgets (line, sizeof (line), this->socket)) {
287                                 loop = 0;
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 (loop) */
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 } /* static void *collect (void *) */
381 static void *open_connection (void __attribute__((unused)) *arg)
383         struct sockaddr_un addr;
385         char *path  = (NULL == sock_file) ? SOCK_PATH : sock_file;
386         char *group = (NULL == sock_group) ? COLLECTD_GRP_NAME : sock_group;
388         /* create UNIX socket */
389         errno = 0;
390         if (-1 == (connector_socket = socket (PF_UNIX, SOCK_STREAM, 0))) {
391                 char errbuf[1024];
392                 disabled = 1;
393                 log_err ("socket() failed: %s",
394                                 sstrerror (errno, errbuf, sizeof (errbuf)));
395                 pthread_exit ((void *)1);
396         }
398         addr.sun_family = AF_UNIX;
399         sstrncpy (addr.sun_path, path, (size_t)(UNIX_PATH_MAX - 1));
401         errno = 0;
402         if (-1 == bind (connector_socket, (struct sockaddr *)&addr,
403                                 offsetof (struct sockaddr_un, sun_path)
404                                         + strlen(addr.sun_path))) {
405                 char errbuf[1024];
406                 disabled = 1;
407                 close (connector_socket);
408                 connector_socket = -1;
409                 log_err ("bind() failed: %s",
410                                 sstrerror (errno, errbuf, sizeof (errbuf)));
411                 pthread_exit ((void *)1);
412         }
414         errno = 0;
415         if (-1 == listen (connector_socket, 5)) {
416                 char errbuf[1024];
417                 disabled = 1;
418                 close (connector_socket);
419                 connector_socket = -1;
420                 log_err ("listen() failed: %s",
421                                 sstrerror (errno, errbuf, sizeof (errbuf)));
422                 pthread_exit ((void *)1);
423         }
425         {
426                 struct group sg;
427                 struct group *grp;
428                 char grbuf[2048];
429                 int status;
431                 grp = NULL;
432                 status = getgrnam_r (group, &sg, grbuf, sizeof (grbuf), &grp);
433                 if (status != 0)
434                 {
435                         char errbuf[1024];
436                         log_warn ("getgrnam_r (%s) failed: %s", group,
437                                         sstrerror (errno, errbuf, sizeof (errbuf)));
438                 }
439                 else if (grp == NULL)
440                 {
441                         log_warn ("No such group: `%s'", group);
442                 }
443                 else
444                 {
445                         status = chown (path, (uid_t) -1, grp->gr_gid);
446                         if (status != 0)
447                         {
448                                 char errbuf[1024];
449                                 log_warn ("chown (%s, -1, %i) failed: %s",
450                                                 path, (int) grp->gr_gid,
451                                                 sstrerror (errno, errbuf, sizeof (errbuf)));
452                         }
453                 }
454         }
456         errno = 0;
457         if (0 != chmod (path, sock_perms)) {
458                 char errbuf[1024];
459                 log_warn ("chmod() failed: %s",
460                                 sstrerror (errno, errbuf, sizeof (errbuf)));
461         }
463         { /* initialize collector threads */
464                 int i   = 0;
465                 int err = 0;
467                 pthread_attr_t ptattr;
469                 conns.head = NULL;
470                 conns.tail = NULL;
472                 pthread_attr_init (&ptattr);
473                 pthread_attr_setdetachstate (&ptattr, PTHREAD_CREATE_DETACHED);
475                 available_collectors = max_conns;
477                 collectors =
478                         (collector_t **)smalloc (max_conns * sizeof (collector_t *));
480                 for (i = 0; i < max_conns; ++i) {
481                         collectors[i] = (collector_t *)smalloc (sizeof (collector_t));
482                         collectors[i]->socket = NULL;
484                         if (0 != (err = pthread_create (&collectors[i]->thread, &ptattr,
485                                                         collect, collectors[i]))) {
486                                 char errbuf[1024];
487                                 log_err ("pthread_create() failed: %s",
488                                                 sstrerror (errno, errbuf, sizeof (errbuf)));
489                                 collectors[i]->thread = (pthread_t) 0;
490                         }
491                 }
493                 pthread_attr_destroy (&ptattr);
494         }
496         while (1) {
497                 int remote = 0;
499                 conn_t *connection;
501                 pthread_mutex_lock (&available_mutex);
503                 while (0 == available_collectors) {
504                         pthread_cond_wait (&collector_available, &available_mutex);
505                 }
507                 --available_collectors;
509                 pthread_mutex_unlock (&available_mutex);
511                 do {
512                         errno = 0;
513                         if (-1 == (remote = accept (connector_socket, NULL, NULL))) {
514                                 if (EINTR != errno) {
515                                         char errbuf[1024];
516                                         disabled = 1;
517                                         close (connector_socket);
518                                         connector_socket = -1;
519                                         log_err ("accept() failed: %s",
520                                                         sstrerror (errno, errbuf, sizeof (errbuf)));
521                                         pthread_exit ((void *)1);
522                                 }
523                         }
524                 } while (EINTR == errno);
526                 connection = (conn_t *)smalloc (sizeof (conn_t));
528                 connection->socket = fdopen (remote, "r");
529                 connection->next   = NULL;
531                 if (NULL == connection->socket) {
532                         close (remote);
533                         continue;
534                 }
536                 pthread_mutex_lock (&conns_mutex);
538                 if (NULL == conns.head) {
539                         conns.head = connection;
540                         conns.tail = connection;
541                 }
542                 else {
543                         conns.tail->next = connection;
544                         conns.tail = conns.tail->next;
545                 }
547                 pthread_mutex_unlock (&conns_mutex);
549                 pthread_cond_signal (&conn_available);
550         }
551         pthread_exit ((void *)0);
552 } /* static void *open_connection (void *) */
554 static int email_init (void)
556         int err = 0;
558         if (0 != (err = pthread_create (&connector, NULL,
559                                 open_connection, NULL))) {
560                 char errbuf[1024];
561                 disabled = 1;
562                 log_err ("pthread_create() failed: %s",
563                                 sstrerror (errno, errbuf, sizeof (errbuf)));
564                 return (-1);
565         }
567         return (0);
568 } /* int email_init */
570 static int email_shutdown (void)
572         type_t *ptr = NULL;
574         int i = 0;
576         if (connector != ((pthread_t) 0)) {
577                 pthread_kill (connector, SIGTERM);
578                 connector = (pthread_t) 0;
579         }
581         if (connector_socket >= 0) {
582                 close (connector_socket);
583                 connector_socket = -1;
584         }
586         /* don't allow any more connections to be processed */
587         pthread_mutex_lock (&conns_mutex);
589         available_collectors = 0;
591         if (collectors != NULL) {
592                 for (i = 0; i < max_conns; ++i) {
593                         if (collectors[i] == NULL)
594                                 continue;
596                         if (collectors[i]->thread != ((pthread_t) 0)) {
597                                 pthread_kill (collectors[i]->thread, SIGTERM);
598                                 collectors[i]->thread = (pthread_t) 0;
599                         }
601                         if (collectors[i]->socket != NULL) {
602                                 fclose (collectors[i]->socket);
603                                 collectors[i]->socket = NULL;
604                         }
606                         sfree (collectors[i]);
607                 }
608                 sfree (collectors);
609         } /* if (collectors != NULL) */
611         pthread_mutex_unlock (&conns_mutex);
613         for (ptr = list_count.head; NULL != ptr; ptr = ptr->next) {
614                 free (ptr->name);
615                 free (ptr);
616         }
618         for (ptr = list_count_copy.head; NULL != ptr; ptr = ptr->next) {
619                 free (ptr->name);
620                 free (ptr);
621         }
623         for (ptr = list_size.head; NULL != ptr; ptr = ptr->next) {
624                 free (ptr->name);
625                 free (ptr);
626         }
628         for (ptr = list_size_copy.head; NULL != ptr; ptr = ptr->next) {
629                 free (ptr->name);
630                 free (ptr);
631         }
633         for (ptr = list_check.head; NULL != ptr; ptr = ptr->next) {
634                 free (ptr->name);
635                 free (ptr);
636         }
638         for (ptr = list_check_copy.head; NULL != ptr; ptr = ptr->next) {
639                 free (ptr->name);
640                 free (ptr);
641         }
643         unlink ((NULL == sock_file) ? SOCK_PATH : sock_file);
645         sfree (sock_file);
646         sfree (sock_group);
647         return (0);
648 } /* static void email_shutdown (void) */
650 static void email_submit (const char *type, const char *type_instance, gauge_t value)
652         value_t values[1];
653         value_list_t vl = VALUE_LIST_INIT;
655         values[0].gauge = value;
657         vl.values = values;
658         vl.values_len = 1;
659         sstrncpy (vl.host, hostname_g, sizeof (vl.host));
660         sstrncpy (vl.plugin, "email", sizeof (vl.plugin));
661         sstrncpy (vl.type, type, sizeof (vl.type));
662         sstrncpy (vl.type_instance, type_instance, sizeof (vl.type_instance));
664         plugin_dispatch_values (&vl);
665 } /* void email_submit */
667 /* Copy list l1 to list l2. l2 may partly exist already, but it is assumed
668  * that neither the order nor the name of any element of either list is
669  * changed and no elements are deleted. The values of l1 are reset to zero
670  * after they have been copied to l2. */
671 static void copy_type_list (type_list_t *l1, type_list_t *l2)
673         type_t *ptr1;
674         type_t *ptr2;
676         type_t *last = NULL;
678         for (ptr1 = l1->head, ptr2 = l2->head; NULL != ptr1;
679                         ptr1 = ptr1->next, last = ptr2, ptr2 = ptr2->next) {
680                 if (NULL == ptr2) {
681                         ptr2 = (type_t *)smalloc (sizeof (type_t));
682                         ptr2->name = NULL;
683                         ptr2->next = NULL;
685                         if (NULL == last) {
686                                 l2->head = ptr2;
687                         }
688                         else {
689                                 last->next = ptr2;
690                         }
692                         l2->tail = ptr2;
693                 }
695                 if (NULL == ptr2->name) {
696                         ptr2->name = sstrdup (ptr1->name);
697                 }
699                 ptr2->value = ptr1->value;
700                 ptr1->value = 0;
701         }
702         return;
705 static int email_read (void)
707         type_t *ptr;
709         double score_old;
710         int score_count_old;
712         if (disabled)
713                 return (-1);
715         /* email count */
716         pthread_mutex_lock (&count_mutex);
718         copy_type_list (&list_count, &list_count_copy);
720         pthread_mutex_unlock (&count_mutex);
722         for (ptr = list_count_copy.head; NULL != ptr; ptr = ptr->next) {
723                 email_submit ("email_count", ptr->name, ptr->value);
724         }
726         /* email size */
727         pthread_mutex_lock (&size_mutex);
729         copy_type_list (&list_size, &list_size_copy);
731         pthread_mutex_unlock (&size_mutex);
733         for (ptr = list_size_copy.head; NULL != ptr; ptr = ptr->next) {
734                 email_submit ("email_size", ptr->name, ptr->value);
735         }
737         /* spam score */
738         pthread_mutex_lock (&score_mutex);
740         score_old = score;
741         score_count_old = score_count;
742         score = 0.0;
743         score_count = 0;
745         pthread_mutex_unlock (&score_mutex);
747         if (score_count_old > 0)
748                 email_submit ("spam_score", "", score_old);
750         /* spam checks */
751         pthread_mutex_lock (&check_mutex);
753         copy_type_list (&list_check, &list_check_copy);
755         pthread_mutex_unlock (&check_mutex);
757         for (ptr = list_check_copy.head; NULL != ptr; ptr = ptr->next)
758                 email_submit ("spam_check", ptr->name, ptr->value);
760         return (0);
761 } /* int email_read */
763 void module_register (void)
765         plugin_register_config ("email", email_config, config_keys, config_keys_num);
766         plugin_register_init ("email", email_init);
767         plugin_register_read ("email", email_read);
768         plugin_register_shutdown ("email", email_shutdown);
769 } /* void module_register */
771 /* vim: set sw=4 ts=4 tw=78 noexpandtab : */