iptables: Support for user defined chain jumps
[framework/connectivity/connman.git] / src / iptables.c
1 /*
2  *
3  *  Connection Manager
4  *
5  *  Copyright (C) 2007-2010  Intel Corporation. All rights reserved.
6  *
7  *  This program is free software; you can redistribute it and/or modify
8  *  it under the terms of the GNU General Public License version 2 as
9  *  published by the Free Software Foundation.
10  *
11  *  This program is distributed in the hope that it will be useful,
12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  *  GNU General Public License for more details.
15  *
16  *  You should have received a copy of the GNU General Public License
17  *  along with this program; if not, write to the Free Software
18  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
19  *
20  */
21
22 #ifdef HAVE_CONFIG_H
23 #include <config.h>
24 #endif
25
26 #include <getopt.h>
27 #include <stdlib.h>
28 #include <stdio.h>
29 #include <string.h>
30 #include <unistd.h>
31 #include <sys/errno.h>
32 #include <sys/socket.h>
33 #include <xtables.h>
34
35 #include <linux/netfilter_ipv4/ip_tables.h>
36
37 #include "connman.h"
38
39
40 static const char *hooknames[] = {
41         [NF_IP_PRE_ROUTING]     = "PREROUTING",
42         [NF_IP_LOCAL_IN]        = "INPUT",
43         [NF_IP_FORWARD]         = "FORWARD",
44         [NF_IP_LOCAL_OUT]       = "OUTPUT",
45         [NF_IP_POST_ROUTING]    = "POSTROUTING",
46 };
47
48 #define LABEL_ACCEPT  "ACCEPT"
49 #define LABEL_DROP    "DROP"
50 #define LABEL_QUEUE   "QUEUE"
51 #define LABEL_RETURN  "RETURN"
52
53 /* fn returns 0 to continue iteration */
54 #define _XT_ENTRY_ITERATE_CONTINUE(type, entries, size, n, fn, args...) \
55 ({                                                              \
56         unsigned int __i;                                       \
57         int __n;                                                \
58         int __ret = 0;                                          \
59         type *__entry;                                          \
60                                                                 \
61         for (__i = 0, __n = 0; __i < (size);                    \
62              __i += __entry->next_offset, __n++) {              \
63                 __entry = (void *)(entries) + __i;              \
64                 if (__n < n)                                    \
65                         continue;                               \
66                                                                 \
67                 __ret = fn(__entry,  ## args);                  \
68                 if (__ret != 0)                                 \
69                         break;                                  \
70         }                                                       \
71         __ret;                                                  \
72 })
73
74 /* fn returns 0 to continue iteration */
75 #define _XT_ENTRY_ITERATE(type, entries, size, fn, args...) \
76         _XT_ENTRY_ITERATE_CONTINUE(type, entries, size, 0, fn, args)
77
78 #define ENTRY_ITERATE(entries, size, fn, args...) \
79         _XT_ENTRY_ITERATE(struct ipt_entry, entries, size, fn, ## args)
80
81 #define MIN_ALIGN (__alignof__(struct ipt_entry))
82
83 #define ALIGN(s) (((s) + ((MIN_ALIGN)-1)) & ~((MIN_ALIGN)-1))
84
85 struct ipt_error_target {
86         struct xt_entry_target t;
87         char error[IPT_TABLE_MAXNAMELEN];
88 };
89
90 struct connman_iptables_entry {
91         int offset;
92
93         struct ipt_entry *entry;
94 };
95
96 struct connman_iptables {
97         int ipt_sock;
98
99         struct ipt_getinfo *info;
100         struct ipt_get_entries *blob_entries;
101
102         unsigned int num_entries;
103         unsigned int old_entries;
104         unsigned int size;
105
106         GList *entries;
107 };
108
109 static GHashTable *table_hash = NULL;
110
111 static struct ipt_entry *get_entry(struct connman_iptables *table,
112                                         unsigned int offset)
113 {
114         return (struct ipt_entry *)((char *)table->blob_entries->entrytable +
115                                                                         offset);
116 }
117
118 static int is_hook_entry(struct connman_iptables *table,
119                                 struct ipt_entry *entry)
120 {
121         unsigned int i;
122
123         for (i = 0; i < NF_INET_NUMHOOKS; i++) {
124                 if ((table->info->valid_hooks & (1 << i))
125                 && get_entry(table, table->info->hook_entry[i]) == entry)
126                         return i;
127         }
128
129         return -1;
130 }
131
132 static unsigned long entry_to_offset(struct connman_iptables *table,
133                                         struct ipt_entry *entry)
134 {
135         return (void *)entry - (void *)table->blob_entries->entrytable;
136 }
137
138 static int target_to_verdict(char *target_name)
139 {
140         if (!strcmp(target_name, LABEL_ACCEPT))
141                 return -NF_ACCEPT - 1;
142
143         if (!strcmp(target_name, LABEL_DROP))
144                 return -NF_DROP - 1;
145
146         if (!strcmp(target_name, LABEL_QUEUE))
147                 return -NF_QUEUE - 1;
148
149         if (!strcmp(target_name, LABEL_RETURN))
150                 return XT_RETURN;
151
152         return 0;
153 }
154
155 static gboolean is_builtin_target(char *target_name)
156 {
157         if (!strcmp(target_name, LABEL_ACCEPT) ||
158                 !strcmp(target_name, LABEL_DROP) ||
159                 !strcmp(target_name, LABEL_QUEUE) ||
160                 !strcmp(target_name, LABEL_RETURN))
161                 return TRUE;
162
163         return FALSE;
164 }
165
166 static gboolean is_jump(struct connman_iptables_entry *e)
167 {
168         struct xt_entry_target *target;
169
170         target = ipt_get_target(e->entry);
171
172         if (!strcmp(target->u.user.name, IPT_STANDARD_TARGET)) {
173                 struct xt_standard_target *t;
174
175                 t = (struct xt_standard_target *)target;
176
177                 switch (t->verdict) {
178                 case XT_RETURN:
179                 case -NF_ACCEPT - 1:
180                 case -NF_DROP - 1:
181                 case -NF_QUEUE - 1:
182                 case -NF_STOP - 1:
183                         return false;
184
185                 default:
186                         return true;
187                 }
188         }
189
190         return false;
191 }
192
193 static gboolean is_chain(struct connman_iptables *table,
194                                 struct connman_iptables_entry *e)
195 {
196         int builtin;
197         struct ipt_entry *entry;
198         struct xt_entry_target *target;
199
200         entry = e->entry;
201         builtin = is_hook_entry(table, entry);
202         if (builtin >= 0)
203                 return TRUE;
204
205         target = ipt_get_target(entry);
206         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET))
207                 return TRUE;
208
209         return FALSE;
210 }
211
212 static GList *find_chain_head(struct connman_iptables *table,
213                                 char *chain_name)
214 {
215         GList *list;
216         struct connman_iptables_entry *head;
217         struct ipt_entry *entry;
218         struct xt_entry_target *target;
219         int builtin;
220
221         for (list = table->entries; list; list = list->next) {
222                 head = list->data;
223                 entry = head->entry;
224
225                 /* Buit-in chain */
226                 builtin = is_hook_entry(table, entry);
227                 if (builtin >= 0 && !strcmp(hooknames[builtin], chain_name))
228                         break;
229
230                 /* User defined chain */
231                 target = ipt_get_target(entry);
232                 if (!strcmp(target->u.user.name, IPT_ERROR_TARGET) &&
233                     !strcmp((char *)target->data, chain_name))
234                         break;
235         }
236
237         return list;
238 }
239
240 static GList *find_chain_tail(struct connman_iptables *table,
241                                 char *chain_name)
242 {
243         GList *chain_head, *list;
244         struct connman_iptables_entry *head, *tail;
245         struct ipt_entry *entry;
246         struct xt_entry_target *target;
247         int builtin;
248
249         /* First we look for the head */
250         for (list = table->entries; list; list = list->next) {
251                 head = list->data;
252                 entry = head->entry;
253
254                 /* Buit-in chain */
255                 builtin = is_hook_entry(table, entry);
256                 if (builtin >= 0 && !strcmp(hooknames[builtin], chain_name))
257                         break;
258
259                 /* User defined chain */
260                 target = ipt_get_target(entry);
261                 if (!strcmp(target->u.user.name, IPT_ERROR_TARGET) &&
262                     !strcmp((char *)target->data, chain_name))
263                         break;
264         }
265
266         if (list == NULL)
267                 return NULL;
268
269         chain_head = list;
270
271         /* Then we look for the next chain */
272         for (list = chain_head->next; list; list = list->next) {
273                 tail = list->data;
274                 entry = tail->entry;
275
276                 if (is_chain(table, tail))
277                         return list;
278         }
279
280         /* Nothing found, we return the table end */
281         return g_list_last(table->entries);
282 }
283
284
285 static void update_offsets(struct connman_iptables *table)
286 {
287         GList *list, *prev;
288         struct connman_iptables_entry *entry, *prev_entry;
289
290         for (list = table->entries; list; list = list->next) {
291                 entry = list->data;
292
293                 if (list == table->entries) {
294                         entry->offset = 0;
295
296                         continue;
297                 }
298
299                 prev = list->prev;
300                 prev_entry = prev->data;
301
302                 entry->offset = prev_entry->offset +
303                                         prev_entry->entry->next_offset;
304         }
305 }
306
307 static int iptables_add_entry(struct connman_iptables *table,
308                                 struct ipt_entry *entry, GList *before)
309 {
310         GList *list;
311         struct connman_iptables_entry *e, *tmp, *entry_before;
312         struct xt_standard_target *t;
313
314         if (table == NULL)
315                 return -1;
316
317         e = g_try_malloc0(sizeof(struct connman_iptables_entry));
318         if (e == NULL)
319                 return -1;
320
321         e->entry = entry;
322
323         table->entries = g_list_insert_before(table->entries, before, e);
324         table->num_entries++;
325         table->size += entry->next_offset;
326
327         if (before == NULL) {
328                 e->offset = table->size - entry->next_offset;
329
330                 return 0;
331         }
332
333         entry_before = before->data;
334
335         /*
336          * We've just insterted a new entry. All references before it
337          * should be bumped accordingly.
338          */
339         for (list = table->entries; list != before; list = list->next) {
340                 tmp = list->data;
341
342                 if (!is_jump(tmp))
343                         continue;
344
345                 t = (struct xt_standard_target *)ipt_get_target(tmp->entry);
346
347                 if (t->verdict >= entry_before->offset)
348                         t->verdict += entry->next_offset;
349         }
350
351         update_offsets(table);
352
353         return 0;
354 }
355
356 static int iptables_add_chain(struct connman_iptables *table,
357                                         char *name)
358 {
359         GList *last;
360         struct ipt_entry *entry_head;
361         struct ipt_entry *entry_return;
362         struct ipt_error_target *error;
363         struct ipt_standard_target *standard;
364         u_int16_t entry_head_size, entry_return_size;
365
366         last = g_list_last(table->entries);
367
368         /*
369          * An empty chain is composed of:
370          * - A head entry, with no match and an error target.
371          *   The error target data is the chain name.
372          * - A tail entry, with no match and a standard target.
373          *   The standard target verdict is XT_RETURN (return to the
374          *   caller).
375          */
376
377         /* head entry */
378         entry_head_size = sizeof(struct ipt_entry) +
379                                 sizeof(struct ipt_error_target);
380         entry_head = g_try_malloc0(entry_head_size);
381         if (entry_head == NULL)
382                 goto err;
383
384         memset(entry_head, 0, entry_head_size);
385
386         entry_head->target_offset = sizeof(struct ipt_entry);
387         entry_head->next_offset = entry_head_size;
388
389         error = (struct ipt_error_target *) entry_head->elems;
390         strcpy(error->t.u.user.name, IPT_ERROR_TARGET);
391         error->t.u.user.target_size = ALIGN(sizeof(struct ipt_error_target));
392         strcpy(error->error, name);
393
394         if (iptables_add_entry(table, entry_head, last) < 0)
395                 goto err;
396
397         /* tail entry */
398         entry_return_size = sizeof(struct ipt_entry) +
399                                 sizeof(struct ipt_standard_target);
400         entry_return = g_try_malloc0(entry_return_size);
401         if (entry_return == NULL)
402                 goto err;
403
404         memset(entry_return, 0, entry_return_size);
405
406         entry_return->target_offset = sizeof(struct ipt_entry);
407         entry_return->next_offset = entry_return_size;
408
409         standard = (struct ipt_standard_target *) entry_return->elems;
410         standard->target.u.user.target_size =
411                                 ALIGN(sizeof(struct ipt_standard_target));
412         standard->verdict = XT_RETURN;
413
414         if (iptables_add_entry(table, entry_return, last) < 0)
415                 goto err;
416
417         return 0;
418
419 err:
420         g_free(entry_head);
421         g_free(entry_return);
422
423         return -ENOMEM;
424 }
425
426 static struct ipt_entry *
427 new_rule(struct connman_iptables *table,
428                 char *target_name, struct xtables_target *xt_t,
429                 char *match_name, struct xtables_match *xt_m)
430 {
431         struct ipt_entry *new_entry;
432         size_t match_size, target_size;
433         int is_builtin = is_builtin_target(target_name);
434
435         if (xt_m)
436                 match_size = xt_m->m->u.match_size;
437         else
438                 match_size = 0;
439
440         if (xt_t)
441                 target_size = ALIGN(xt_t->t->u.target_size);
442         else
443                 target_size = ALIGN(sizeof(struct xt_standard_target));
444
445         new_entry = g_try_malloc0(sizeof(struct ipt_entry) + target_size +
446                                                                 match_size);
447         if (new_entry == NULL)
448                 return NULL;
449
450         new_entry->target_offset = sizeof(struct ipt_entry) + match_size;
451         new_entry->next_offset = sizeof(struct ipt_entry) + target_size +
452                                                                 match_size;
453         if (xt_m) {
454                 struct xt_entry_match *entry_match;
455
456                 entry_match = (struct xt_entry_match *)new_entry->elems;
457                 memcpy(entry_match, xt_m->m, match_size);
458         }
459
460         if (xt_t) {
461                 struct xt_entry_target *entry_target;
462
463                 if (is_builtin) {
464                         struct xt_standard_target *target;
465
466                         target = (struct xt_standard_target *)(xt_t->t);
467                         strcpy(target->target.u.user.name, IPT_STANDARD_TARGET);
468                         target->verdict = target_to_verdict(target_name);
469                 }
470
471                 entry_target = ipt_get_target(new_entry);
472                 memcpy(entry_target, xt_t->t, target_size);
473         } else {
474                 struct connman_iptables_entry *target_rule;
475                 struct xt_standard_target *target;
476                 GList *chain_head;
477
478                 /*
479                  * This is a user defined target, i.e. a chain jump.
480                  * We search for the chain head, and the target verdict
481                  * is the first rule's offset on this chain.
482                  * The offset is from the beginning of the table.
483                  */
484
485                 chain_head = find_chain_head(table, target_name);
486                 if (chain_head == NULL || chain_head->next == NULL) {
487                         g_free(new_entry);
488                         return NULL;
489                 }
490
491                 target_rule = chain_head->next->data;
492
493                 target = (struct xt_standard_target *)ipt_get_target(new_entry);
494                 strcpy(target->target.u.user.name, IPT_STANDARD_TARGET);
495                 target->target.u.user.target_size = target_size;
496                 target->verdict = target_rule->offset;
497         }
498
499         return new_entry;
500 }
501
502 static int
503 iptables_add_rule(struct connman_iptables *table, char *chain_name,
504                                 char *target_name, struct xtables_target *xt_t,
505                                 char *match_name, struct xtables_match *xt_m)
506 {
507         GList *chain_tail;
508         struct ipt_entry *new_entry;
509
510         chain_tail = find_chain_tail(table, chain_name);
511         if (chain_tail == NULL)
512                 return -EINVAL;
513
514         new_entry = new_rule(table,
515                                 target_name, xt_t,
516                                 match_name, xt_m);
517         if (new_entry == NULL)
518                 return -EINVAL;
519
520         return iptables_add_entry(table, new_entry, chain_tail->prev);
521 }
522
523 static struct ipt_replace *
524 iptables_blob(struct connman_iptables *table)
525 {
526         struct ipt_replace *r;
527         GList *list;
528         struct connman_iptables_entry *e;
529         unsigned char *entry_index;
530
531         r = g_try_malloc0(sizeof(struct ipt_replace) + table->size);
532         if (r == NULL)
533                 return NULL;
534
535         memset(r, 0, sizeof(*r) + table->size);
536
537         r->counters = g_try_malloc0(sizeof(struct xt_counters)
538                                 * table->num_entries);
539         if (r->counters == NULL) {
540                 g_free(r);
541                 return NULL;
542         }
543
544         strcpy(r->name, table->info->name);
545         r->num_entries = table->num_entries;
546         r->size = table->size;
547
548         r->num_counters = table->old_entries;
549         r->valid_hooks  = table->info->valid_hooks;
550
551         memcpy(r->hook_entry, table->info->hook_entry,
552                                 sizeof(table->info->hook_entry));
553         memcpy(r->underflow, table->info->underflow,
554                                 sizeof(table->info->underflow));
555
556         entry_index = (unsigned char *)r->entries;
557         for (list = table->entries; list; list = list->next) {
558                 e = list->data;
559
560                 memcpy(entry_index, e->entry, e->entry->next_offset);
561                 entry_index += e->entry->next_offset;
562         }
563
564         return r;
565 }
566
567 static void dump_target(struct connman_iptables *table,
568                                 struct ipt_entry *entry)
569
570 {
571         struct xtables_target *xt_t;
572         struct xt_entry_target *target;
573
574         target = ipt_get_target(entry);
575
576         if (!strcmp(target->u.user.name, IPT_STANDARD_TARGET)) {
577                 struct xt_standard_target *t;
578
579                 t = (struct xt_standard_target *)target;
580
581                 switch (t->verdict) {
582                 case XT_RETURN:
583                         connman_info("\ttarget RETURN");
584                         break;
585
586                 case -NF_ACCEPT - 1:
587                         connman_info("\ttarget ACCEPT");
588                         break;
589
590                 case -NF_DROP - 1:
591                         connman_info("\ttarget DROP");
592                         break;
593
594                 case -NF_QUEUE - 1:
595                         connman_info("\ttarget QUEUE");
596                         break;
597
598                 case -NF_STOP - 1:
599                         connman_info("\ttarget STOP");
600                         break;
601
602                 default:
603                         connman_info("\tJUMP @%p (0x%x)",
604                                 (char*)table->blob_entries->entrytable +
605                                 t->verdict, t->verdict);
606                         break;
607                 }
608
609                 xt_t = xtables_find_target(IPT_STANDARD_TARGET,
610                                                 XTF_LOAD_MUST_SUCCEED);
611
612                 if(xt_t->print != NULL)
613                         xt_t->print(NULL, target, 1);
614         } else {
615                 xt_t = xtables_find_target(target->u.user.name, XTF_TRY_LOAD);
616                 if (xt_t == NULL) {
617                         connman_info("\ttarget %s", target->u.user.name);
618                         return;
619                 }
620
621                 if(xt_t->print != NULL) {
622                         connman_info("\ttarget ");
623                         xt_t->print(NULL, target, 1);
624                 }
625         }
626 }
627
628 static void dump_match(struct connman_iptables *table, struct ipt_entry *entry)
629 {
630         struct xtables_match *xt_m;
631         struct xt_entry_match *match;
632
633         if (entry->elems == (unsigned char *)entry + entry->target_offset)
634                 return;
635
636         match = (struct xt_entry_match *) entry->elems;
637
638         if (!strlen(match->u.user.name))
639                 return;
640
641         xt_m = xtables_find_match(match->u.user.name, XTF_TRY_LOAD, NULL);
642         if (xt_m == NULL)
643                 goto out;
644
645         if(xt_m->print != NULL) {
646                 connman_info("\tmatch ");
647                 xt_m->print(NULL, match, 1);
648
649                 return;
650         }
651
652 out:
653         connman_info("\tmatch %s", match->u.user.name);
654
655 }
656
657 static int dump_entry(struct ipt_entry *entry,
658                                 struct connman_iptables *table)
659 {
660         struct xt_entry_target *target;
661         unsigned int offset;
662         int builtin;
663
664         offset = (char *)entry - (char *)table->blob_entries->entrytable;
665         target = ipt_get_target(entry);
666         builtin = is_hook_entry(table, entry);
667
668         if (entry_to_offset(table, entry) + entry->next_offset ==
669                                         table->blob_entries->size) {
670                 connman_info("End of CHAIN 0x%x", offset);
671                 return 0;
672         }
673
674         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET)) {
675                 connman_info("USER CHAIN (%s) %p  match %p  target %p  size %d",
676                         target->data, entry, entry->elems,
677                         (char *)entry + entry->target_offset,
678                                 entry->next_offset);
679
680                 return 0;
681         } else if (builtin >= 0) {
682                 connman_info("CHAIN (%s) %p  match %p  target %p  size %d",
683                         hooknames[builtin], entry, entry->elems,
684                         (char *)entry + entry->target_offset,
685                                 entry->next_offset);
686         } else {
687                 connman_info("RULE %p  match %p  target %p  size %d", entry,
688                         entry->elems,
689                         (char *)entry + entry->target_offset,
690                                 entry->next_offset);
691         }
692
693         dump_match(table, entry);
694         dump_target(table, entry);
695
696         return 0;
697 }
698
699 static void iptables_dump(struct connman_iptables *table)
700 {
701         connman_info("%s valid_hooks=0x%08x, num_entries=%u, size=%u",
702                         table->info->name,
703                         table->info->valid_hooks, table->info->num_entries,
704                                 table->info->size);
705
706         ENTRY_ITERATE(table->blob_entries->entrytable,
707                         table->blob_entries->size,
708                         dump_entry, table);
709
710 }
711
712 static int iptables_get_entries(struct connman_iptables *table)
713 {
714         socklen_t entry_size;
715
716         entry_size = sizeof(struct ipt_get_entries) + table->info->size;
717
718         return getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_ENTRIES,
719                                 table->blob_entries, &entry_size);
720 }
721
722 static int iptables_replace(struct connman_iptables *table,
723                                         struct ipt_replace *r)
724 {
725         return setsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_SET_REPLACE, r,
726                          sizeof(*r) + r->size);
727 }
728
729 static int add_entry(struct ipt_entry *entry, struct connman_iptables *table)
730 {
731         struct ipt_entry *new_entry;
732
733         new_entry = g_try_malloc0(entry->next_offset);
734         if (new_entry == NULL)
735                 return -ENOMEM;
736
737         memcpy(new_entry, entry, entry->next_offset);
738
739         return iptables_add_entry(table, new_entry, NULL);
740 }
741
742 static void table_cleanup(struct connman_iptables *table)
743 {
744         GList *list;
745         struct connman_iptables_entry *entry;
746
747         close(table->ipt_sock);
748
749         for (list = table->entries; list; list = list->next) {
750                 entry = list->data;
751
752                 g_free(entry->entry);
753         }
754
755         g_list_free(table->entries);
756         g_free(table->info);
757         g_free(table->blob_entries);
758         g_free(table);
759 }
760
761 static struct connman_iptables *iptables_init(char *table_name)
762 {
763         struct connman_iptables *table;
764         socklen_t s;
765
766         table = g_hash_table_lookup(table_hash, table_name);
767         if (table != NULL)
768                 return table;
769
770         table = g_try_new0(struct connman_iptables, 1);
771         if (table == NULL)
772                 return NULL;
773
774         table->info = g_try_new0(struct ipt_getinfo, 1);
775         if (table->info == NULL)
776                 goto err;
777
778         table->ipt_sock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
779         if (table->ipt_sock < 0)
780                 goto err;
781
782         s = sizeof(*table->info);
783         strcpy(table->info->name, table_name);
784         if (getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_INFO,
785                                                 table->info, &s) < 0)
786                 goto err;
787
788         table->blob_entries = g_try_malloc0(sizeof(struct ipt_get_entries) +
789                                                 table->info->size);
790         if (table->blob_entries == NULL)
791                 goto err;
792
793         strcpy(table->blob_entries->name, table_name);
794         table->blob_entries->size = table->info->size;
795
796         if (iptables_get_entries(table) < 0)
797                 goto err;
798
799         table->num_entries = 0;
800         table->old_entries = table->info->num_entries;
801         table->size = 0;
802
803         ENTRY_ITERATE(table->blob_entries->entrytable,
804                         table->blob_entries->size,
805                                 add_entry, table);
806
807         g_hash_table_insert(table_hash, table_name, table);
808
809         return table;
810
811 err:
812
813         table_cleanup(table);
814
815         return NULL;
816 }
817
818 static struct option iptables_opts[] = {
819         {.name = "append",        .has_arg = 1, .val = 'A'},
820         {.name = "list",          .has_arg = 2, .val = 'L'},
821         {.name = "new-chain",     .has_arg = 1, .val = 'N'},
822         {.name = "in-interface",  .has_arg = 1, .val = 'i'},
823         {.name = "jump",          .has_arg = 1, .val = 'j'},
824         {.name = "match",         .has_arg = 1, .val = 'm'},
825         {.name = "out-interface", .has_arg = 1, .val = 'o'},
826         {.name = "table",         .has_arg = 1, .val = 't'},
827         {NULL},
828 };
829
830 struct xtables_globals iptables_globals = {
831         .option_offset = 0,
832         .opts = iptables_opts,
833         .orig_opts = iptables_opts,
834 };
835
836 static int iptables_command(int argc, char *argv[])
837 {
838         struct connman_iptables *table;
839         struct xtables_match *xt_m;
840         struct xtables_target *xt_t;
841         char *table_name, *chain, *new_chain, *match_name, *target_name;
842         int c, ret;
843         size_t size;
844         gboolean dump, invert;
845
846         if (argc == 0)
847                 return -EINVAL;
848
849         dump = FALSE;
850         invert = FALSE;
851         table_name = chain = new_chain = match_name = target_name = NULL;
852         table = NULL;
853         xt_m = NULL;
854         xt_t = NULL;
855         ret = 0;
856
857         optind = 0;
858
859         while ((c = getopt_long(argc, argv,
860            "-A:L::N:j:i:m:o:t:", iptables_globals.opts, NULL)) != -1) {
861                 switch (c) {
862                 case 'A':
863                         chain = optarg;
864                         break;
865
866                 case 'L':
867                         dump = TRUE;
868                         break;
869
870                 case 'N':
871                         new_chain = optarg;
872                         break;
873
874                 case 'j':
875                         target_name = optarg;
876                         xt_t = xtables_find_target(target_name, XTF_TRY_LOAD);
877
878                         if (xt_t == NULL)
879                                 break;
880
881                         size = ALIGN(sizeof(struct ipt_entry_target)) +
882                                                                 xt_t->size;
883
884                         xt_t->t = g_try_malloc0(size);
885                         if (xt_t->t == NULL)
886                                 goto out;
887                         xt_t->t->u.target_size = size;
888                         strcpy(xt_t->t->u.user.name, target_name);
889                         xt_t->t->u.user.revision = xt_t->revision;
890                         if (xt_t->init != NULL)
891                                 xt_t->init(xt_t->t);
892                         iptables_globals.opts =
893                                 xtables_merge_options(iptables_globals.opts,
894                                                      xt_t->extra_opts,
895                                                      &xt_t->option_offset);
896                         if (iptables_globals.opts == NULL)
897                                 goto out;
898
899                         break;
900
901                 case 'i':
902                         break;
903
904                 case 'm':
905                         match_name = optarg;
906
907                         xt_m = xtables_find_match(optarg, XTF_LOAD_MUST_SUCCEED, NULL);
908                         size = ALIGN(sizeof(struct ipt_entry_match)) +
909                                                                 xt_m->size;
910                         xt_m->m = g_try_malloc0(size);
911                         if (xt_m == NULL)
912                                 goto out;
913                         xt_m->m->u.match_size = size;
914                         strcpy(xt_m->m->u.user.name, xt_m->name);
915                         xt_m->m->u.user.revision = xt_m->revision;
916                         if (xt_m->init != NULL)
917                                 xt_m->init(xt_m->m);
918                         if (xt_m != xt_m->next) {
919                                 iptables_globals.opts =
920                                 xtables_merge_options(iptables_globals.opts,
921                                                 xt_m->extra_opts,
922                                                 &xt_m->option_offset);
923                                 if (iptables_globals.opts == NULL)
924                                         goto out;
925                         }
926
927                         break;
928
929                 case 'o':
930                         break;
931
932                 case 't':
933                         table_name = optarg;
934                         break;
935
936                 case 1:
937                         if (optarg[0] == '!' && optarg[1] == '\0') {
938                                 invert = TRUE;
939                                 optarg[0] = '\0';
940                                 continue;
941                         }
942
943                         connman_error("Invalid option");
944
945                         ret = -EINVAL;
946                         goto out;
947
948                 default:
949                         if (xt_t == NULL || xt_t->parse == NULL ||
950                             !xt_t->parse(c - xt_t->option_offset, argv, invert,
951                                         &xt_t->tflags, NULL, &xt_t->t)) {
952                                 if (xt_m == NULL || xt_m->parse == NULL)
953                                         break;
954
955                                 xt_m->parse(c - xt_m->option_offset, argv,
956                                         invert, &xt_m->mflags, NULL, &xt_m->m);
957                         }
958
959                         break;
960                 }
961         }
962
963         if (table_name == NULL)
964                 table_name = "filter";
965
966         table = iptables_init(table_name);
967         if (table == NULL) {
968                 ret = -EINVAL;
969                 goto out;
970         }
971
972         if (dump) {
973                 iptables_dump(table);
974
975                 ret = 0;
976                 goto out;
977         }
978
979         if (chain && new_chain) {
980                 ret = -EINVAL;
981                 goto out;
982         }
983
984         if (new_chain) {
985                 DBG("New chain %s", new_chain);
986
987                 ret = iptables_add_chain(table, new_chain);
988                 goto out;
989         }
990
991         if (chain) {
992                 if (target_name == NULL)
993                         return -1;
994
995                 DBG("Adding %s to %s (match %s)",
996                                 target_name, chain, match_name);
997
998                 ret = iptables_add_rule(table, chain, target_name, xt_t,
999                                         match_name, xt_m);
1000
1001                 goto out;
1002         }
1003
1004 out:
1005         if (xt_t)
1006                 g_free(xt_t->t);
1007
1008         if (xt_m)
1009                 g_free(xt_m->m);
1010
1011         return ret;
1012 }
1013
1014 int __connman_iptables_command(const char *format, ...)
1015 {
1016         char **argv, **arguments, *command;
1017         int argc, i, ret;
1018         va_list args;
1019
1020         if (format == NULL)
1021                 return -EINVAL;
1022
1023         va_start(args, format);
1024
1025         command = g_strdup_vprintf(format, args);
1026
1027         va_end(args);
1028
1029         if (command == NULL)
1030                 return -ENOMEM;
1031
1032         arguments = g_strsplit_set(command, " ", -1);
1033
1034         for (argc = 0; arguments[argc]; argc++);
1035
1036         DBG("command %s argc %d", command, ++argc);
1037
1038         argv = g_try_malloc0(argc * sizeof(char *));
1039         if (argv == NULL) {
1040                 g_free(command);
1041                 g_strfreev(arguments);
1042                 return -ENOMEM;
1043         }
1044
1045         argv[0] = "iptables";
1046         for (i = 1; i < argc; i++)
1047                 argv[i] = arguments[i - 1];
1048
1049         ret = iptables_command(argc, argv);
1050
1051         g_free(command);
1052         g_strfreev(arguments);
1053         g_free(argv);
1054
1055         return ret;
1056 }
1057
1058
1059 int __connman_iptables_commit(const char *table_name)
1060 {
1061         struct connman_iptables *table;
1062         struct ipt_replace *repl;
1063
1064         table = g_hash_table_lookup(table_hash, table_name);
1065         if (table == NULL)
1066                 return -EINVAL;
1067
1068         repl = iptables_blob(table);
1069
1070         return iptables_replace(table, repl);
1071 }
1072
1073 static void remove_table(gpointer user_data)
1074 {
1075         struct connman_iptables *table = user_data;
1076
1077         table_cleanup(table);
1078 }
1079
1080 int __connman_iptables_init(void)
1081 {
1082         DBG("");
1083
1084         table_hash = g_hash_table_new_full(g_str_hash, g_str_equal,
1085                                                 NULL, remove_table);
1086
1087         xtables_init_all(&iptables_globals, NFPROTO_IPV4);
1088
1089         return 0;
1090
1091 }
1092
1093 void __connman_iptables_cleanup(void)
1094 {
1095         g_hash_table_destroy(table_hash);
1096
1097         xtables_free_opts(1);
1098 }