1 /**
2 * collectd - src/iptables.c
3 * Copyright (C) 2007 Sjoerd van der Berg
4 * Copyright (C) 2007-2010 Florian octo Forster
5 * Copyright (C) 2009 Marco Chiappero
6 *
7 * This program is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License as published by the
9 * Free Software Foundation; either version 2 of the License, or (at your
10 * option) any later version.
11 *
12 * This program is distributed in the hope that it will be useful, but
13 * WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * General Public License for more details.
16 *
17 * You should have received a copy of the GNU General Public License along
18 * with this program; if not, write to the Free Software Foundation, Inc.,
19 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
20 *
21 * Authors:
22 * Sjoerd van der Berg <harekiet at users.sourceforge.net>
23 * Florian Forster <octo at collectd.org>
24 * Marco Chiappero <marco at absence.it>
25 **/
27 #include "collectd.h"
28 #include "common.h"
29 #include "plugin.h"
30 #include "configfile.h"
32 #include <libiptc/libiptc.h>
33 #include <libiptc/libip6tc.h>
35 /*
36 * iptc_handle_t was available before libiptc was officially available as a
37 * shared library. Note, that when the shared lib was introduced, the API and
38 * ABI have changed slightly:
39 * 'iptc_handle_t' used to be 'struct iptc_handle *' and most functions used
40 * 'iptc_handle_t *' as an argument. Now, most functions use 'struct
41 * iptc_handle *' (thus removing one level of pointer indirection).
42 *
43 * HAVE_IPTC_HANDLE_T is used to determine which API ought to be used. While
44 * this is somewhat hacky, I didn't find better way to solve that :-/
45 * -tokkee
46 */
47 #ifndef HAVE_IPTC_HANDLE_T
48 typedef struct iptc_handle iptc_handle_t;
49 #endif
50 #ifndef HAVE_IP6TC_HANDLE_T
51 typedef struct ip6tc_handle ip6tc_handle_t;
52 #endif
54 /*
55 * (Module-)Global variables
56 */
58 /*
59 * Config format should be `Chain table chainname',
60 * e. g. `Chain mangle incoming'
61 */
62 static const char *config_keys[] =
63 {
64 "Chain",
65 "Chain6"
66 };
67 static int config_keys_num = STATIC_ARRAY_SIZE (config_keys);
68 enum protocol_version_e
69 {
70 IPV4,
71 IPV6
72 };
73 typedef enum protocol_version_e protocol_version_t;
75 /*
76 * Each table/chain combo that will be queried goes into this list
77 */
78 #ifndef XT_TABLE_MAXNAMELEN
79 # define XT_TABLE_MAXNAMELEN 32
80 #endif
81 typedef struct {
82 protocol_version_t ip_version;
83 char table[XT_TABLE_MAXNAMELEN];
84 char chain[XT_TABLE_MAXNAMELEN];
85 union
86 {
87 int num;
88 char *comment;
89 } rule;
90 enum
91 {
92 RTYPE_NUM,
93 RTYPE_COMMENT,
94 RTYPE_COMMENT_ALL
95 } rule_type;
96 char name[64];
97 } ip_chain_t;
99 static ip_chain_t **chain_list = NULL;
100 static int chain_num = 0;
102 static int iptables_config (const char *key, const char *value)
103 {
104 /* int ip_value; */
105 protocol_version_t ip_version = 0;
107 if (strcasecmp (key, "Chain") == 0)
108 ip_version = IPV4;
109 else if (strcasecmp (key, "Chain6") == 0)
110 ip_version = IPV6;
111 else
112 return (1);
114 ip_chain_t temp = { 0 };
115 ip_chain_t *final, **list;
116 char *table;
117 int table_len;
118 char *chain;
119 int chain_len;
121 char *value_copy;
122 char *fields[4];
123 int fields_num;
125 value_copy = strdup (value);
126 if (value_copy == NULL)
127 {
128 char errbuf[1024];
129 ERROR ("strdup failed: %s",
130 sstrerror (errno, errbuf, sizeof (errbuf)));
131 return (1);
132 }
134 /*
135 * Time to fill the temp element
136 * Examine value string, it should look like:
137 * Chain[6] <table> <chain> [<comment|num> [name]]
138 */
140 /* set IPv4 or IPv6 */
141 temp.ip_version = ip_version;
143 /* Chain <table> <chain> [<comment|num> [name]] */
144 fields_num = strsplit (value_copy, fields, 4);
145 if (fields_num < 2)
146 {
147 free (value_copy);
148 return (1);
149 }
151 table = fields[0];
152 chain = fields[1];
154 table_len = strlen (table) + 1;
155 if ((unsigned int)table_len > sizeof(temp.table))
156 {
157 ERROR ("Table `%s' too long.", table);
158 free (value_copy);
159 return (1);
160 }
161 sstrncpy (temp.table, table, table_len);
163 chain_len = strlen (chain) + 1;
164 if ((unsigned int)chain_len > sizeof(temp.chain))
165 {
166 ERROR ("Chain `%s' too long.", chain);
167 free (value_copy);
168 return (1);
169 }
170 sstrncpy (temp.chain, chain, chain_len);
172 if (fields_num >= 3)
173 {
174 char *comment = fields[2];
175 int rule = atoi (comment);
177 if (rule)
178 {
179 temp.rule.num = rule;
180 temp.rule_type = RTYPE_NUM;
181 }
182 else
183 {
184 temp.rule.comment = strdup (comment);
185 if (temp.rule.comment == NULL)
186 {
187 free (value_copy);
188 return (1);
189 }
190 temp.rule_type = RTYPE_COMMENT;
191 }
192 }
193 else
194 {
195 temp.rule_type = RTYPE_COMMENT_ALL;
196 }
198 if (fields_num >= 4)
199 sstrncpy (temp.name, fields[3], sizeof (temp.name));
201 free (value_copy);
202 value_copy = NULL;
203 table = NULL;
204 chain = NULL;
206 list = realloc (chain_list, (chain_num + 1) * sizeof (ip_chain_t *));
207 if (list == NULL)
208 {
209 char errbuf[1024];
210 ERROR ("realloc failed: %s",
211 sstrerror (errno, errbuf, sizeof (errbuf)));
212 sfree (temp.rule.comment);
213 return (1);
214 }
216 chain_list = list;
217 final = malloc(sizeof (*final));
218 if (final == NULL)
219 {
220 char errbuf[1024];
221 ERROR ("malloc failed: %s",
222 sstrerror (errno, errbuf, sizeof (errbuf)));
223 sfree (temp.rule.comment);
224 return (1);
225 }
226 memcpy (final, &temp, sizeof (temp));
227 chain_list[chain_num] = final;
228 chain_num++;
230 DEBUG ("Chain #%i: table = %s; chain = %s;", chain_num, final->table, final->chain);
232 return (0);
233 } /* int iptables_config */
235 static int submit6_match (const struct ip6t_entry_match *match,
236 const struct ip6t_entry *entry,
237 const ip_chain_t *chain,
238 int rule_num)
239 {
240 int status;
241 value_t values[1];
242 value_list_t vl = VALUE_LIST_INIT;
244 /* Select the rules to collect */
245 if (chain->rule_type == RTYPE_NUM)
246 {
247 if (chain->rule.num != rule_num)
248 return (0);
249 }
250 else
251 {
252 if (strcmp (match->u.user.name, "comment") != 0)
253 return (0);
254 if ((chain->rule_type == RTYPE_COMMENT)
255 && (strcmp (chain->rule.comment, (char *) match->data) != 0))
256 return (0);
257 }
259 vl.values = values;
260 vl.values_len = 1;
261 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
262 sstrncpy (vl.plugin, "ip6tables", sizeof (vl.plugin));
264 status = ssnprintf (vl.plugin_instance, sizeof (vl.plugin_instance),
265 "%s-%s", chain->table, chain->chain);
266 if ((status < 1) || ((unsigned int)status >= sizeof (vl.plugin_instance)))
267 return (0);
269 if (chain->name[0] != '\0')
270 {
271 sstrncpy (vl.type_instance, chain->name, sizeof (vl.type_instance));
272 }
273 else
274 {
275 if (chain->rule_type == RTYPE_NUM)
276 ssnprintf (vl.type_instance, sizeof (vl.type_instance),
277 "%i", chain->rule.num);
278 else
279 sstrncpy (vl.type_instance, (char *) match->data,
280 sizeof (vl.type_instance));
281 }
283 sstrncpy (vl.type, "ipt_bytes", sizeof (vl.type));
284 values[0].derive = (derive_t) entry->counters.bcnt;
285 plugin_dispatch_values (&vl);
287 sstrncpy (vl.type, "ipt_packets", sizeof (vl.type));
288 values[0].derive = (derive_t) entry->counters.pcnt;
289 plugin_dispatch_values (&vl);
291 return (0);
292 } /* int submit_match */
295 /* This needs to return `int' for IPT_MATCH_ITERATE to work. */
296 static int submit_match (const struct ipt_entry_match *match,
297 const struct ipt_entry *entry,
298 const ip_chain_t *chain,
299 int rule_num)
300 {
301 int status;
302 value_t values[1];
303 value_list_t vl = VALUE_LIST_INIT;
305 /* Select the rules to collect */
306 if (chain->rule_type == RTYPE_NUM)
307 {
308 if (chain->rule.num != rule_num)
309 return (0);
310 }
311 else
312 {
313 if (strcmp (match->u.user.name, "comment") != 0)
314 return (0);
315 if ((chain->rule_type == RTYPE_COMMENT)
316 && (strcmp (chain->rule.comment, (char *) match->data) != 0))
317 return (0);
318 }
320 vl.values = values;
321 vl.values_len = 1;
322 sstrncpy (vl.host, hostname_g, sizeof (vl.host));
323 sstrncpy (vl.plugin, "iptables", sizeof (vl.plugin));
325 status = ssnprintf (vl.plugin_instance, sizeof (vl.plugin_instance),
326 "%s-%s", chain->table, chain->chain);
327 if ((status < 1) || ((unsigned int)status >= sizeof (vl.plugin_instance)))
328 return (0);
330 if (chain->name[0] != '\0')
331 {
332 sstrncpy (vl.type_instance, chain->name, sizeof (vl.type_instance));
333 }
334 else
335 {
336 if (chain->rule_type == RTYPE_NUM)
337 ssnprintf (vl.type_instance, sizeof (vl.type_instance),
338 "%i", chain->rule.num);
339 else
340 sstrncpy (vl.type_instance, (char *) match->data,
341 sizeof (vl.type_instance));
342 }
344 sstrncpy (vl.type, "ipt_bytes", sizeof (vl.type));
345 values[0].derive = (derive_t) entry->counters.bcnt;
346 plugin_dispatch_values (&vl);
348 sstrncpy (vl.type, "ipt_packets", sizeof (vl.type));
349 values[0].derive = (derive_t) entry->counters.pcnt;
350 plugin_dispatch_values (&vl);
352 return (0);
353 } /* int submit_match */
356 /* ipv6 submit_chain */
357 static void submit6_chain (ip6tc_handle_t *handle, ip_chain_t *chain)
358 {
359 const struct ip6t_entry *entry;
360 int rule_num;
362 /* Find first rule for chain and use the iterate macro */
363 entry = ip6tc_first_rule( chain->chain, handle );
364 if (entry == NULL)
365 {
366 DEBUG ("ip6tc_first_rule failed: %s", ip6tc_strerror (errno));
367 return;
368 }
370 rule_num = 1;
371 while (entry)
372 {
373 if (chain->rule_type == RTYPE_NUM)
374 {
375 submit6_match (NULL, entry, chain, rule_num);
376 }
377 else
378 {
379 IP6T_MATCH_ITERATE( entry, submit6_match, entry, chain, rule_num );
380 }
382 entry = ip6tc_next_rule( entry, handle );
383 rule_num++;
384 } /* while (entry) */
385 }
388 /* ipv4 submit_chain */
389 static void submit_chain (iptc_handle_t *handle, ip_chain_t *chain)
390 {
391 const struct ipt_entry *entry;
392 int rule_num;
394 /* Find first rule for chain and use the iterate macro */
395 entry = iptc_first_rule( chain->chain, handle );
396 if (entry == NULL)
397 {
398 DEBUG ("iptc_first_rule failed: %s", iptc_strerror (errno));
399 return;
400 }
402 rule_num = 1;
403 while (entry)
404 {
405 if (chain->rule_type == RTYPE_NUM)
406 {
407 submit_match (NULL, entry, chain, rule_num);
408 }
409 else
410 {
411 IPT_MATCH_ITERATE( entry, submit_match, entry, chain, rule_num );
412 }
414 entry = iptc_next_rule( entry, handle );
415 rule_num++;
416 } /* while (entry) */
417 }
420 static int iptables_read (void)
421 {
422 int i;
423 int num_failures = 0;
424 ip_chain_t *chain;
426 /* Init the iptc handle structure and query the correct table */
427 for (i = 0; i < chain_num; i++)
428 {
429 chain = chain_list[i];
431 if (!chain)
432 {
433 DEBUG ("iptables plugin: chain == NULL");
434 continue;
435 }
437 if ( chain->ip_version == IPV4 )
438 {
439 #ifdef HAVE_IPTC_HANDLE_T
440 iptc_handle_t _handle;
441 iptc_handle_t *handle = &_handle;
443 *handle = iptc_init (chain->table);
444 #else
445 iptc_handle_t *handle;
446 handle = iptc_init (chain->table);
447 #endif
449 if (!handle)
450 {
451 ERROR ("iptables plugin: iptc_init (%s) failed: %s",
452 chain->table, iptc_strerror (errno));
453 num_failures++;
454 continue;
455 }
457 submit_chain (handle, chain);
458 iptc_free (handle);
459 }
460 else if ( chain->ip_version == IPV6 )
461 {
462 #ifdef HAVE_IP6TC_HANDLE_T
463 ip6tc_handle_t _handle;
464 ip6tc_handle_t *handle = &_handle;
466 *handle = ip6tc_init (chain->table);
467 #else
468 ip6tc_handle_t *handle;
469 handle = ip6tc_init (chain->table);
470 #endif
471 if (!handle)
472 {
473 ERROR ("iptables plugin: ip6tc_init (%s) failed: %s",
474 chain->table, ip6tc_strerror (errno));
475 num_failures++;
476 continue;
477 }
479 submit6_chain (handle, chain);
480 ip6tc_free (handle);
481 }
482 else
483 num_failures++;
484 } /* for (i = 0 .. chain_num) */
486 return ((num_failures < chain_num) ? 0 : -1);
487 } /* int iptables_read */
489 static int iptables_shutdown (void)
490 {
491 int i;
493 for (i = 0; i < chain_num; i++)
494 {
495 if ((chain_list[i] != NULL) && (chain_list[i]->rule_type == RTYPE_COMMENT))
496 sfree (chain_list[i]->rule.comment);
497 sfree (chain_list[i]);
498 }
499 sfree (chain_list);
501 return (0);
502 } /* int iptables_shutdown */
504 void module_register (void)
505 {
506 plugin_register_config ("iptables", iptables_config,
507 config_keys, config_keys_num);
508 plugin_register_read ("iptables", iptables_read);
509 plugin_register_shutdown ("iptables", iptables_shutdown);
510 } /* void module_register */