iptables: Always update options table
[platform/upstream/connman.git] / src / iptables.c
1 /*
2  *
3  *  Connection Manager
4  *
5  *  Copyright (C) 2007-2012  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 void flush_table(const char *name);
40
41 /*
42  * Some comments on how the iptables API works (some of them from the
43  * source code from iptables and the kernel):
44  *
45  * - valid_hooks: bit indicates valid IDs for hook_entry
46  * - hook_entry[ID] offset to the chain start
47  * - overflows should be end of entry chains, and uncodintional policy nodes.
48  * - policy entry: last entry in a chain
49  * - user chain: end of last builtin + policy entry
50  * - final entry must be error node
51  * - Underflows must be unconditional and use the STANDARD target with
52  *   ACCEPT/DROP
53  * - IPT_SO_GET_INFO and IPT_SO_GET_ENTRIES are used to read a table
54  * - IPT_SO_GET_INFO: struct ipt_getinfo (note the lack of table content)
55  * - IPT_SO_GET_ENTRIES: struct ipt_get_entries (contains only parts of the
56  *   table header/meta info. The table is appended after the header. The entries
57  *   are of the type struct ipt_entry.
58  * - After the ipt_entry the matches are appended. After the matches
59  *   the target is appended.
60  * - ipt_entry->target_offset =  Size of ipt_entry + matches
61  * - ipt_entry->next_offset =  Size of ipt_entry + matches + target
62  * - IPT_SO_SET_REPLACE is used to write a table (contains the complete
63  * - hook_entry and overflow mark the begining and the end of a chain, e.g
64  *     entry hook: pre/in/fwd/out/post -1/0/352/504/-1
65  *     underflow:  pre/in/fwd/out/post -1/200/352/904/-1
66  *   means that INPUT starts at offset 0 and ends at 200 (the start offset to
67  *   the last element). FORWARD has one entry starting/ending at 352. The entry
68  *   has a size of 152. 352 + 152 = 504 which is the start of the OUTPUT chain
69  *   which then ends at 904. PREROUTING and POSTROUTING are invalid hooks in
70  *   the filter table.
71  * - 'iptables -t filter -A INPUT -m mark --mark 999 -j LOG'
72  *   writing that table looks like this:
73  *
74  *   filter valid_hooks 0x0000000e  num_entries 5  size 856
75  *   entry hook: pre/in/fwd/out/post -1/0/376/528/-1
76  *   underflow:  pre/in/fwd/out/post -1/224/376/528/-1
77  *   entry 0x699d30  offset 0  size 224
78  *     RULE  match 0x699da0  target 0x699dd0
79  *             match  mark match 0x3e7
80  *             target  LOG flags 0 level 4
81  *             src 0.0.0.0/0.0.0.0
82  *             dst 0.0.0.0/0.0.0.0
83  *   entry 0x699e10  offset 224  size 152
84  *     RULE  match 0x699e80  target 0x699e80
85  *             target ACCEPT
86  *             src 0.0.0.0/0.0.0.0
87  *             dst 0.0.0.0/0.0.0.0
88  *   entry 0x699ea8  offset 376  size 152
89  *     RULE  match 0x699f18  target 0x699f18
90  *             target ACCEPT
91  *             src 0.0.0.0/0.0.0.0
92  *             dst 0.0.0.0/0.0.0.0
93  *   entry 0x699f40  offset 528  size 152
94  *     RULE  match 0x699fb0  target 0x699fb0
95  *             target ACCEPT
96  *             src 0.0.0.0/0.0.0.0
97  *             dst 0.0.0.0/0.0.0.0
98  *   entry 0x699fd8  offset 680  size 176
99  *     USER CHAIN (ERROR)  match 0x69a048  target 0x69a048
100  *
101  *   Reading the filter table looks like this:
102  *
103  *   filter valid_hooks 0x0000000e  num_entries 5  size 856
104  *   entry hook: pre/in/fwd/out/post -1/0/376/528/-1
105  *   underflow:  pre/in/fwd/out/post -1/224/376/528/-1
106  *   entry 0x25fec28  offset 0  size 224
107  *     CHAIN (INPUT)  match 0x25fec98  target 0x25fecc8
108  *             match  mark match 0x3e7
109  *             target  LOG flags 0 level 4
110  *             src 0.0.0.0/0.0.0.0
111  *             dst 0.0.0.0/0.0.0.0
112  *   entry 0x25fed08  offset 224  size 152
113  *     RULE  match 0x25fed78  target 0x25fed78
114  *             target ACCEPT
115  *             src 0.0.0.0/0.0.0.0
116  *             dst 0.0.0.0/0.0.0.0
117  *   entry 0x25feda0  offset 376  size 152
118  *     CHAIN (FORWARD)  match 0x25fee10  target 0x25fee10
119  *             target ACCEPT
120  *             src 0.0.0.0/0.0.0.0
121  *             dst 0.0.0.0/0.0.0.0
122  *   entry 0x25fee38  offset 528  size 152
123  *     CHAIN (OUTPUT)  match 0x25feea8  target 0x25feea8
124  *             target ACCEPT
125  *             src 0.0.0.0/0.0.0.0
126  *             dst 0.0.0.0/0.0.0.0
127  *   entry 0x25feed0  offset 680  size 176
128  *     End of CHAIN
129  */
130
131 static const char *hooknames[] = {
132         [NF_IP_PRE_ROUTING]     = "PREROUTING",
133         [NF_IP_LOCAL_IN]        = "INPUT",
134         [NF_IP_FORWARD]         = "FORWARD",
135         [NF_IP_LOCAL_OUT]       = "OUTPUT",
136         [NF_IP_POST_ROUTING]    = "POSTROUTING",
137 };
138
139 #define LABEL_ACCEPT  "ACCEPT"
140 #define LABEL_DROP    "DROP"
141 #define LABEL_QUEUE   "QUEUE"
142 #define LABEL_RETURN  "RETURN"
143
144 #define XT_OPTION_OFFSET_SCALE 256
145
146 #define MIN_ALIGN (__alignof__(struct ipt_entry))
147
148 #define ALIGN(s) (((s) + ((MIN_ALIGN)-1)) & ~((MIN_ALIGN)-1))
149
150 struct error_target {
151         struct xt_entry_target t;
152         char error[IPT_TABLE_MAXNAMELEN];
153 };
154
155 struct connman_iptables_entry {
156         int offset;
157         int builtin;
158
159         struct ipt_entry *entry;
160 };
161
162 struct connman_iptables {
163         int ipt_sock;
164
165         struct ipt_getinfo *info;
166         struct ipt_get_entries *blob_entries;
167
168         unsigned int num_entries;
169         unsigned int old_entries;
170         unsigned int size;
171
172         unsigned int underflow[NF_INET_NUMHOOKS];
173         unsigned int hook_entry[NF_INET_NUMHOOKS];
174
175         GList *entries;
176 };
177
178 static GHashTable *table_hash = NULL;
179 static gboolean debug_enabled = FALSE;
180
181 typedef int (*iterate_entries_cb_t)(struct ipt_entry *entry, int builtin,
182                                         unsigned int hook,size_t size,
183                                         unsigned int offset, void *user_data);
184
185 static unsigned int next_hook_entry_index(unsigned int *valid_hooks)
186 {
187         unsigned int h;
188
189         if (*valid_hooks == 0)
190                 return NF_INET_NUMHOOKS;
191
192         h = __builtin_ffs(*valid_hooks) - 1;
193         *valid_hooks ^= (1 << h);
194
195         return h;
196 }
197
198 static int iterate_entries(struct ipt_entry *entries,
199                                 unsigned int valid_hooks,
200                                 unsigned int *hook_entry,
201                                 unsigned int *underflow,
202                                 size_t size, iterate_entries_cb_t cb,
203                                 void *user_data)
204 {
205         unsigned int offset, h, hook;
206         int builtin, err;
207         struct ipt_entry *entry;
208
209         h = next_hook_entry_index(&valid_hooks);
210         hook = h;
211
212         for (offset = 0, entry = entries; offset < size;
213                         offset += entry->next_offset) {
214                 builtin = -1;
215                 entry = (void *)entries + offset;
216
217                 /*
218                  * Updating builtin, hook and h is very tricky.
219                  * The rules are:
220                  * - builtin is only set to the current hook number
221                  *   if the current entry is the hook entry (aka chain
222                  *   head). And only for builtin chains, never for
223                  *   the user chains.
224                  * - hook is the current hook number. If we
225                  *   look at user chains it needs to be NF_INET_NETNUMHOOKS.
226                  * - h is the next hook entry. Thous we need to be carefully
227                  *   not to access the table when h is NF_INET_NETNUMHOOKS.
228                  */
229                 if (h < NF_INET_NUMHOOKS && hook_entry[h] == offset) {
230                         builtin = h;
231                         hook = h;
232                 }
233
234                 if (h == NF_INET_NUMHOOKS)
235                         hook = h;
236
237                 if (h < NF_INET_NUMHOOKS && underflow[h] <= offset) {
238                         h = next_hook_entry_index(&valid_hooks);
239                 }
240
241                 err = cb(entry, builtin, hook, size, offset, user_data);
242                 if (err < 0)
243                         return err;
244         }
245
246         return 0;
247 }
248
249 static int print_entry(struct ipt_entry *entry, int builtin, unsigned int hook,
250                                         size_t size, unsigned int offset,
251                                         void *user_data)
252 {
253         iterate_entries_cb_t cb = user_data;
254
255         DBG("entry %p  hook %d  offset %d  size %d", entry, hook,
256                         offset, entry->next_offset);
257
258         return cb(entry, builtin, hook, size, offset, NULL);
259 }
260
261 static int target_to_verdict(const char *target_name)
262 {
263         if (!strcmp(target_name, LABEL_ACCEPT))
264                 return -NF_ACCEPT - 1;
265
266         if (!strcmp(target_name, LABEL_DROP))
267                 return -NF_DROP - 1;
268
269         if (!strcmp(target_name, LABEL_QUEUE))
270                 return -NF_QUEUE - 1;
271
272         if (!strcmp(target_name, LABEL_RETURN))
273                 return XT_RETURN;
274
275         return 0;
276 }
277
278 static gboolean is_builtin_target(const char *target_name)
279 {
280         if (!strcmp(target_name, LABEL_ACCEPT) ||
281                 !strcmp(target_name, LABEL_DROP) ||
282                 !strcmp(target_name, LABEL_QUEUE) ||
283                 !strcmp(target_name, LABEL_RETURN))
284                 return TRUE;
285
286         return FALSE;
287 }
288
289 static gboolean is_jump(struct connman_iptables_entry *e)
290 {
291         struct xt_entry_target *target;
292
293         target = ipt_get_target(e->entry);
294
295         if (!strcmp(target->u.user.name, IPT_STANDARD_TARGET)) {
296                 struct xt_standard_target *t;
297
298                 t = (struct xt_standard_target *)target;
299
300                 switch (t->verdict) {
301                 case XT_RETURN:
302                 case -NF_ACCEPT - 1:
303                 case -NF_DROP - 1:
304                 case -NF_QUEUE - 1:
305                 case -NF_STOP - 1:
306                         return false;
307
308                 default:
309                         return true;
310                 }
311         }
312
313         return false;
314 }
315
316 static gboolean is_fallthrough(struct connman_iptables_entry *e)
317 {
318         struct xt_entry_target *target;
319
320         target = ipt_get_target(e->entry);
321         if (!g_strcmp0(target->u.user.name, IPT_STANDARD_TARGET)) {
322                 struct xt_standard_target *t;
323
324                 t = (struct xt_standard_target *)target;
325                 if (t->verdict == 0)
326                         return true;
327         }
328         return false;
329 }
330
331 static gboolean is_chain(struct connman_iptables *table,
332                                 struct connman_iptables_entry *e)
333 {
334         struct ipt_entry *entry;
335         struct xt_entry_target *target;
336
337         entry = e->entry;
338         if (e->builtin >= 0)
339                 return TRUE;
340
341         target = ipt_get_target(entry);
342         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET))
343                 return TRUE;
344
345         return FALSE;
346 }
347
348 static GList *find_chain_head(struct connman_iptables *table,
349                                 const char *chain_name)
350 {
351         GList *list;
352         struct connman_iptables_entry *head;
353         struct ipt_entry *entry;
354         struct xt_entry_target *target;
355         int builtin;
356
357         for (list = table->entries; list; list = list->next) {
358                 head = list->data;
359                 entry = head->entry;
360
361                 /* Buit-in chain */
362                 builtin = head->builtin;
363                 if (builtin >= 0 && !strcmp(hooknames[builtin], chain_name))
364                         break;
365
366                 /* User defined chain */
367                 target = ipt_get_target(entry);
368                 if (!strcmp(target->u.user.name, IPT_ERROR_TARGET) &&
369                     !strcmp((char *)target->data, chain_name))
370                         break;
371         }
372
373         return list;
374 }
375
376 static GList *find_chain_tail(struct connman_iptables *table,
377                                 const char *chain_name)
378 {
379         struct connman_iptables_entry *tail;
380         GList *chain_head, *list;
381
382         chain_head = find_chain_head(table, chain_name);
383         if (chain_head == NULL)
384                 return NULL;
385
386         /* Then we look for the next chain */
387         for (list = chain_head->next; list; list = list->next) {
388                 tail = list->data;
389
390                 if (is_chain(table, tail))
391                         return list;
392         }
393
394         /* Nothing found, we return the table end */
395         return g_list_last(table->entries);
396 }
397
398
399 static void update_offsets(struct connman_iptables *table)
400 {
401         GList *list, *prev;
402         struct connman_iptables_entry *entry, *prev_entry;
403
404         for (list = table->entries; list; list = list->next) {
405                 entry = list->data;
406
407                 if (list == table->entries) {
408                         entry->offset = 0;
409
410                         continue;
411                 }
412
413                 prev = list->prev;
414                 prev_entry = prev->data;
415
416                 entry->offset = prev_entry->offset +
417                                         prev_entry->entry->next_offset;
418         }
419 }
420
421 static void update_targets_reference(struct connman_iptables *table,
422                                 struct connman_iptables_entry *entry_before,
423                                 struct connman_iptables_entry *modified_entry,
424                                 gboolean is_removing)
425 {
426         struct connman_iptables_entry *tmp;
427         struct xt_standard_target *t;
428         GList *list;
429         int offset;
430
431         offset = modified_entry->entry->next_offset;
432
433         for (list = table->entries; list; list = list->next) {
434                 tmp = list->data;
435
436                 if (!is_jump(tmp))
437                         continue;
438
439                 t = (struct xt_standard_target *)ipt_get_target(tmp->entry);
440
441                 if (is_removing == TRUE) {
442                         if (t->verdict >= entry_before->offset)
443                                 t->verdict -= offset;
444                 } else {
445                         if (t->verdict > entry_before->offset)
446                                 t->verdict += offset;
447                 }
448         }
449
450         if (is_fallthrough(modified_entry)) {
451                 t = (struct xt_standard_target *) ipt_get_target(modified_entry->entry);
452
453                 t->verdict = entry_before->offset +
454                         modified_entry->entry->target_offset +
455                         ALIGN(sizeof(struct xt_standard_target));
456                 t->target.u.target_size =
457                         ALIGN(sizeof(struct xt_standard_target));
458         }
459 }
460
461 static int iptables_add_entry(struct connman_iptables *table,
462                                 struct ipt_entry *entry, GList *before,
463                                         int builtin)
464 {
465         struct connman_iptables_entry *e, *entry_before;
466
467         if (table == NULL)
468                 return -1;
469
470         e = g_try_malloc0(sizeof(struct connman_iptables_entry));
471         if (e == NULL)
472                 return -1;
473
474         e->entry = entry;
475         e->builtin = builtin;
476
477         table->entries = g_list_insert_before(table->entries, before, e);
478         table->num_entries++;
479         table->size += entry->next_offset;
480
481         if (before == NULL) {
482                 e->offset = table->size - entry->next_offset;
483
484                 return 0;
485         }
486
487         entry_before = before->data;
488
489         /*
490          * We've just appended/insterted a new entry. All references
491          * should be bumped accordingly.
492          */
493         update_targets_reference(table, entry_before, e, FALSE);
494
495         update_offsets(table);
496
497         return 0;
498 }
499
500 static int remove_table_entry(struct connman_iptables *table,
501                                 struct connman_iptables_entry *entry)
502 {
503         int removed = 0;
504
505         table->num_entries--;
506         table->size -= entry->entry->next_offset;
507         removed = entry->entry->next_offset;
508
509         table->entries = g_list_remove(table->entries, entry);
510
511         g_free(entry->entry);
512         g_free(entry);
513
514         return removed;
515 }
516
517 static int iptables_flush_chain(struct connman_iptables *table,
518                                                 const char *name)
519 {
520         GList *chain_head, *chain_tail, *list, *next;
521         struct connman_iptables_entry *entry;
522         int builtin, removed = 0;
523
524         chain_head = find_chain_head(table, name);
525         if (chain_head == NULL)
526                 return -EINVAL;
527
528         chain_tail = find_chain_tail(table, name);
529         if (chain_tail == NULL)
530                 return -EINVAL;
531
532         entry = chain_head->data;
533         builtin = entry->builtin;
534
535         if (builtin >= 0)
536                 list = chain_head;
537         else
538                 list = chain_head->next;
539
540         if (list == chain_tail->prev)
541                 return 0;
542
543         while (list != chain_tail->prev) {
544                 entry = list->data;
545                 next = g_list_next(list);
546
547                 removed += remove_table_entry(table, entry);
548
549                 list = next;
550         }
551
552         if (builtin >= 0) {
553                 struct connman_iptables_entry *e;
554
555                 entry = list->data;
556
557                 entry->builtin = builtin;
558
559                 table->underflow[builtin] -= removed;
560
561                 for (list = chain_tail; list; list = list->next) {
562                         e = list->data;
563
564                         builtin = e->builtin;
565                         if (builtin < 0)
566                                 continue;
567
568                         table->hook_entry[builtin] -= removed;
569                         table->underflow[builtin] -= removed;
570                 }
571         }
572
573         update_offsets(table);
574
575         return 0;
576 }
577
578 static int iptables_add_chain(struct connman_iptables *table,
579                                 const char *name)
580 {
581         GList *last;
582         struct ipt_entry *entry_head;
583         struct ipt_entry *entry_return;
584         struct error_target *error;
585         struct ipt_standard_target *standard;
586         u_int16_t entry_head_size, entry_return_size;
587
588         last = g_list_last(table->entries);
589
590         /*
591          * An empty chain is composed of:
592          * - A head entry, with no match and an error target.
593          *   The error target data is the chain name.
594          * - A tail entry, with no match and a standard target.
595          *   The standard target verdict is XT_RETURN (return to the
596          *   caller).
597          */
598
599         /* head entry */
600         entry_head_size = sizeof(struct ipt_entry) +
601                                 sizeof(struct error_target);
602         entry_head = g_try_malloc0(entry_head_size);
603         if (entry_head == NULL)
604                 goto err_head;
605
606         memset(entry_head, 0, entry_head_size);
607
608         entry_head->target_offset = sizeof(struct ipt_entry);
609         entry_head->next_offset = entry_head_size;
610
611         error = (struct error_target *) entry_head->elems;
612         strcpy(error->t.u.user.name, IPT_ERROR_TARGET);
613         error->t.u.user.target_size = ALIGN(sizeof(struct error_target));
614         strcpy(error->error, name);
615
616         if (iptables_add_entry(table, entry_head, last, -1) < 0)
617                 goto err_head;
618
619         /* tail entry */
620         entry_return_size = sizeof(struct ipt_entry) +
621                                 sizeof(struct ipt_standard_target);
622         entry_return = g_try_malloc0(entry_return_size);
623         if (entry_return == NULL)
624                 goto err;
625
626         memset(entry_return, 0, entry_return_size);
627
628         entry_return->target_offset = sizeof(struct ipt_entry);
629         entry_return->next_offset = entry_return_size;
630
631         standard = (struct ipt_standard_target *) entry_return->elems;
632         standard->target.u.user.target_size =
633                                 ALIGN(sizeof(struct ipt_standard_target));
634         standard->verdict = XT_RETURN;
635
636         if (iptables_add_entry(table, entry_return, last, -1) < 0)
637                 goto err;
638
639         return 0;
640
641 err:
642         g_free(entry_return);
643 err_head:
644         g_free(entry_head);
645
646         return -ENOMEM;
647 }
648
649 static int iptables_delete_chain(struct connman_iptables *table,
650                                         const char *name)
651 {
652         struct connman_iptables_entry *entry;
653         GList *chain_head, *chain_tail;
654
655         chain_head = find_chain_head(table, name);
656         if (chain_head == NULL)
657                 return -EINVAL;
658
659         entry = chain_head->data;
660
661         /* We cannot remove builtin chain */
662         if (entry->builtin >= 0)
663                 return -EINVAL;
664
665         chain_tail = find_chain_tail(table, name);
666         if (chain_tail == NULL)
667                 return -EINVAL;
668
669         /* Chain must be flushed */
670         if (chain_head->next != chain_tail->prev)
671                 return -EINVAL;
672
673         remove_table_entry(table, entry);
674
675         entry = chain_tail->prev->data;
676         remove_table_entry(table, entry);
677
678         update_offsets(table);
679
680         return 0;
681 }
682
683 static struct ipt_entry *new_rule(struct ipt_ip *ip,
684                 const char *target_name, struct xtables_target *xt_t,
685                 struct xtables_rule_match *xt_rm)
686 {
687         struct xtables_rule_match *tmp_xt_rm;
688         struct ipt_entry *new_entry;
689         size_t match_size, target_size;
690
691         match_size = 0;
692         for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL; tmp_xt_rm = tmp_xt_rm->next)
693                 match_size += tmp_xt_rm->match->m->u.match_size;
694
695         if (xt_t)
696                 target_size = ALIGN(xt_t->t->u.target_size);
697         else
698                 target_size = ALIGN(sizeof(struct xt_standard_target));
699
700         new_entry = g_try_malloc0(sizeof(struct ipt_entry) + target_size +
701                                                                 match_size);
702         if (new_entry == NULL)
703                 return NULL;
704
705         memcpy(&new_entry->ip, ip, sizeof(struct ipt_ip));
706
707         new_entry->target_offset = sizeof(struct ipt_entry) + match_size;
708         new_entry->next_offset = sizeof(struct ipt_entry) + target_size +
709                                                                 match_size;
710
711         match_size = 0;
712         for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL;
713                                 tmp_xt_rm = tmp_xt_rm->next) {
714                 memcpy(new_entry->elems + match_size, tmp_xt_rm->match->m,
715                                         tmp_xt_rm->match->m->u.match_size);
716                 match_size += tmp_xt_rm->match->m->u.match_size;
717         }
718
719         if (xt_t) {
720                 struct xt_entry_target *entry_target;
721
722                 entry_target = ipt_get_target(new_entry);
723                 memcpy(entry_target, xt_t->t, target_size);
724         }
725
726         return new_entry;
727 }
728
729 static void update_hooks(struct connman_iptables *table, GList *chain_head,
730                                 struct ipt_entry *entry)
731 {
732         GList *list;
733         struct connman_iptables_entry *head, *e;
734         int builtin;
735
736         if (chain_head == NULL)
737                 return;
738
739         head = chain_head->data;
740
741         builtin = head->builtin;
742         if (builtin < 0)
743                 return;
744
745         table->underflow[builtin] += entry->next_offset;
746
747         for (list = chain_head->next; list; list = list->next) {
748                 e = list->data;
749
750                 builtin = e->builtin;
751                 if (builtin < 0)
752                         continue;
753
754                 table->hook_entry[builtin] += entry->next_offset;
755                 table->underflow[builtin] += entry->next_offset;
756         }
757 }
758
759 static struct ipt_entry *prepare_rule_inclusion(struct connman_iptables *table,
760                                 struct ipt_ip *ip, const char *chain_name,
761                                 const char *target_name,
762                                 struct xtables_target *xt_t,
763                                 int *builtin, struct xtables_rule_match *xt_rm)
764 {
765         GList *chain_tail, *chain_head;
766         struct ipt_entry *new_entry;
767         struct connman_iptables_entry *head;
768
769         chain_head = find_chain_head(table, chain_name);
770         if (chain_head == NULL)
771                 return NULL;
772
773         chain_tail = find_chain_tail(table, chain_name);
774         if (chain_tail == NULL)
775                 return NULL;
776
777         new_entry = new_rule(ip, target_name, xt_t, xt_rm);
778         if (new_entry == NULL)
779                 return NULL;
780
781         update_hooks(table, chain_head, new_entry);
782
783         /*
784          * If the chain is builtin, and does not have any rule,
785          * then the one that we're inserting is becoming the head
786          * and thus needs the builtin flag.
787          */
788         head = chain_head->data;
789         if (head->builtin < 0)
790                 *builtin = -1;
791         else if (chain_head == chain_tail->prev) {
792                 *builtin = head->builtin;
793                 head->builtin = -1;
794         }
795
796         return new_entry;
797 }
798
799 static int iptables_insert_rule(struct connman_iptables *table,
800                                 struct ipt_ip *ip, const char *chain_name,
801                                 const char *target_name,
802                                 struct xtables_target *xt_t,
803                                 struct xtables_rule_match *xt_rm)
804 {
805         struct ipt_entry *new_entry;
806         int builtin = -1, ret;
807         GList *chain_head;
808
809         chain_head = find_chain_head(table, chain_name);
810         if (chain_head == NULL)
811                 return -EINVAL;
812
813         new_entry = prepare_rule_inclusion(table, ip, chain_name,
814                                         target_name, xt_t, &builtin, xt_rm);
815         if (new_entry == NULL)
816                 return -EINVAL;
817
818         if (builtin == -1)
819                 chain_head = chain_head->next;
820
821         ret = iptables_add_entry(table, new_entry, chain_head, builtin);
822         if (ret < 0)
823                 g_free(new_entry);
824
825         return ret;
826 }
827
828 static gboolean is_same_ipt_entry(struct ipt_entry *i_e1,
829                                         struct ipt_entry *i_e2)
830 {
831         if (memcmp(&i_e1->ip, &i_e2->ip, sizeof(struct ipt_ip)) != 0)
832                 return FALSE;
833
834         if (i_e1->target_offset != i_e2->target_offset)
835                 return FALSE;
836
837         if (i_e1->next_offset != i_e2->next_offset)
838                 return FALSE;
839
840         return TRUE;
841 }
842
843 static gboolean is_same_target(struct xt_entry_target *xt_e_t1,
844                                         struct xt_entry_target *xt_e_t2)
845 {
846         unsigned int i;
847
848         if (xt_e_t1 == NULL || xt_e_t2 == NULL)
849                 return FALSE;
850
851         if (strcmp(xt_e_t1->u.user.name, "") == 0 &&
852                         strcmp(xt_e_t2->u.user.name, "") == 0) {
853                 /* fallthrough */
854                 return TRUE;
855         } else if (strcmp(xt_e_t1->u.user.name, IPT_STANDARD_TARGET) == 0) {
856                 struct xt_standard_target *xt_s_t1;
857                 struct xt_standard_target *xt_s_t2;
858
859                 xt_s_t1 = (struct xt_standard_target *) xt_e_t1;
860                 xt_s_t2 = (struct xt_standard_target *) xt_e_t2;
861
862                 if (xt_s_t1->verdict != xt_s_t2->verdict)
863                         return FALSE;
864         } else {
865                 if (xt_e_t1->u.target_size != xt_e_t2->u.target_size)
866                         return FALSE;
867
868                 if (strcmp(xt_e_t1->u.user.name, xt_e_t2->u.user.name) != 0)
869                         return FALSE;
870
871                 for (i = 0; i < xt_e_t1->u.target_size -
872                                 sizeof(struct xt_standard_target); i++) {
873                         if ((xt_e_t1->data[i] ^ xt_e_t2->data[i]) != 0)
874                                 return FALSE;
875                 }
876         }
877
878         return TRUE;
879 }
880
881 static gboolean is_same_match(struct xt_entry_match *xt_e_m1,
882                                 struct xt_entry_match *xt_e_m2)
883 {
884         unsigned int i;
885
886         if (xt_e_m1 == NULL || xt_e_m2 == NULL)
887                 return FALSE;
888
889         if (xt_e_m1->u.match_size != xt_e_m2->u.match_size)
890                 return FALSE;
891
892         if (xt_e_m1->u.user.revision != xt_e_m2->u.user.revision)
893                 return FALSE;
894
895         if (strcmp(xt_e_m1->u.user.name, xt_e_m2->u.user.name) != 0)
896                 return FALSE;
897
898         for (i = 0; i < xt_e_m1->u.match_size - sizeof(struct xt_entry_match);
899                         i++) {
900                 if ((xt_e_m1->data[i] ^ xt_e_m2->data[i]) != 0)
901                         return FALSE;
902         }
903
904         return TRUE;
905 }
906
907 static GList *find_existing_rule(struct connman_iptables *table,
908                                 struct ipt_ip *ip, const char *chain_name,
909                                 const char *target_name,
910                                 struct xtables_target *xt_t,
911                                 struct xtables_match *xt_m,
912                                 struct xtables_rule_match *xt_rm)
913 {
914         GList *chain_tail, *chain_head, *list;
915         struct xt_entry_target *xt_e_t = NULL;
916         struct xt_entry_match *xt_e_m = NULL;
917         struct connman_iptables_entry *entry;
918         struct ipt_entry *entry_test;
919         int builtin;
920
921         chain_head = find_chain_head(table, chain_name);
922         if (chain_head == NULL)
923                 return NULL;
924
925         chain_tail = find_chain_tail(table, chain_name);
926         if (chain_tail == NULL)
927                 return NULL;
928
929         if (!xt_t && !xt_m)
930                 return NULL;
931
932         entry_test = new_rule(ip, target_name, xt_t, xt_rm);
933         if (entry_test == NULL)
934                 return NULL;
935
936         if (xt_t != NULL)
937                 xt_e_t = ipt_get_target(entry_test);
938         if (xt_m != NULL)
939                 xt_e_m = (struct xt_entry_match *)entry_test->elems;
940
941         entry = chain_head->data;
942         builtin = entry->builtin;
943
944         if (builtin >= 0)
945                 list = chain_head;
946         else
947                 list = chain_head->next;
948
949         for (; list != chain_tail->prev; list = list->next) {
950                 struct connman_iptables_entry *tmp;
951                 struct ipt_entry *tmp_e;
952
953                 tmp = list->data;
954                 tmp_e = tmp->entry;
955
956                 if (is_same_ipt_entry(entry_test, tmp_e) == FALSE)
957                         continue;
958
959                 if (xt_t != NULL) {
960                         struct xt_entry_target *tmp_xt_e_t;
961
962                         tmp_xt_e_t = ipt_get_target(tmp_e);
963
964                         if (!is_same_target(tmp_xt_e_t, xt_e_t))
965                                 continue;
966                 }
967
968                 if (xt_m != NULL) {
969                         struct xt_entry_match *tmp_xt_e_m;
970
971                         tmp_xt_e_m = (struct xt_entry_match *)tmp_e->elems;
972
973                         if (!is_same_match(tmp_xt_e_m, xt_e_m))
974                                 continue;
975                 }
976
977                 break;
978         }
979
980         g_free(entry_test);
981
982         if (list != chain_tail->prev)
983                 return list;
984
985         return NULL;
986 }
987
988 static int iptables_delete_rule(struct connman_iptables *table,
989                                 struct ipt_ip *ip, const char *chain_name,
990                                 const char *target_name,
991                                 struct xtables_target *xt_t,
992                                 struct xtables_match *xt_m,
993                                 struct xtables_rule_match *xt_rm)
994 {
995         struct connman_iptables_entry *entry;
996         GList *chain_head, *chain_tail, *list;
997         int builtin, removed;
998
999         removed = 0;
1000
1001         chain_head = find_chain_head(table, chain_name);
1002         if (chain_head == NULL)
1003                 return -EINVAL;
1004
1005         chain_tail = find_chain_tail(table, chain_name);
1006         if (chain_tail == NULL)
1007                 return -EINVAL;
1008
1009         list = find_existing_rule(table, ip, chain_name, target_name,
1010                                                         xt_t, xt_m, xt_rm);
1011         if (list == NULL)
1012                 return -EINVAL;
1013
1014         entry = chain_head->data;
1015         builtin = entry->builtin;
1016
1017         entry = list->data;
1018         if (entry == NULL)
1019                 return -EINVAL;
1020
1021         /* We have deleted a rule,
1022          * all references should be bumped accordingly */
1023         if (list->next != NULL)
1024                 update_targets_reference(table, list->next->data,
1025                                                 list->data, TRUE);
1026
1027         removed += remove_table_entry(table, entry);
1028
1029         if (builtin >= 0) {
1030                 list = list->next;
1031                 if (list) {
1032                         entry = list->data;
1033                         entry->builtin = builtin;
1034                 }
1035
1036                 table->underflow[builtin] -= removed;
1037                 for (list = chain_tail; list; list = list->next) {
1038                         entry = list->data;
1039
1040                         builtin = entry->builtin;
1041                         if (builtin < 0)
1042                                 continue;
1043
1044                         table->hook_entry[builtin] -= removed;
1045                         table->underflow[builtin] -= removed;
1046                 }
1047         }
1048
1049         update_offsets(table);
1050
1051         return 0;
1052 }
1053
1054 static int iptables_change_policy(struct connman_iptables *table,
1055                                 const char *chain_name, const char *policy)
1056 {
1057         GList *chain_head;
1058         struct connman_iptables_entry *entry;
1059         struct xt_entry_target *target;
1060         struct xt_standard_target *t;
1061         int verdict;
1062
1063         verdict = target_to_verdict(policy);
1064         if (verdict == 0)
1065                 return -EINVAL;
1066
1067         chain_head = find_chain_head(table, chain_name);
1068         if (chain_head == NULL)
1069                 return -EINVAL;
1070
1071         entry = chain_head->data;
1072         if (entry->builtin < 0)
1073                 return -EINVAL;
1074
1075         target = ipt_get_target(entry->entry);
1076
1077         t = (struct xt_standard_target *)target;
1078         t->verdict = verdict;
1079
1080         return 0;
1081 }
1082
1083 static struct ipt_replace *iptables_blob(struct connman_iptables *table)
1084 {
1085         struct ipt_replace *r;
1086         GList *list;
1087         struct connman_iptables_entry *e;
1088         unsigned char *entry_index;
1089
1090         r = g_try_malloc0(sizeof(struct ipt_replace) + table->size);
1091         if (r == NULL)
1092                 return NULL;
1093
1094         memset(r, 0, sizeof(*r) + table->size);
1095
1096         r->counters = g_try_malloc0(sizeof(struct xt_counters)
1097                                 * table->old_entries);
1098         if (r->counters == NULL) {
1099                 g_free(r);
1100                 return NULL;
1101         }
1102
1103         strcpy(r->name, table->info->name);
1104         r->num_entries = table->num_entries;
1105         r->size = table->size;
1106
1107         r->num_counters = table->old_entries;
1108         r->valid_hooks  = table->info->valid_hooks;
1109
1110         memcpy(r->hook_entry, table->hook_entry, sizeof(table->hook_entry));
1111         memcpy(r->underflow, table->underflow, sizeof(table->underflow));
1112
1113         entry_index = (unsigned char *)r->entries;
1114         for (list = table->entries; list; list = list->next) {
1115                 e = list->data;
1116
1117                 memcpy(entry_index, e->entry, e->entry->next_offset);
1118                 entry_index += e->entry->next_offset;
1119         }
1120
1121         return r;
1122 }
1123
1124 static void dump_ip(struct ipt_entry *entry)
1125 {
1126         struct ipt_ip *ip = &entry->ip;
1127         char ip_string[INET6_ADDRSTRLEN];
1128         char ip_mask[INET6_ADDRSTRLEN];
1129
1130         if (strlen(ip->iniface))
1131                 DBG("\tin %s", ip->iniface);
1132
1133         if (strlen(ip->outiface))
1134                 DBG("\tout %s", ip->outiface);
1135
1136         if (inet_ntop(AF_INET, &ip->src, ip_string, INET6_ADDRSTRLEN) != NULL &&
1137                         inet_ntop(AF_INET, &ip->smsk,
1138                                         ip_mask, INET6_ADDRSTRLEN) != NULL)
1139                 DBG("\tsrc %s/%s", ip_string, ip_mask);
1140
1141         if (inet_ntop(AF_INET, &ip->dst, ip_string, INET6_ADDRSTRLEN) != NULL &&
1142                         inet_ntop(AF_INET, &ip->dmsk,
1143                                         ip_mask, INET6_ADDRSTRLEN) != NULL)
1144                 DBG("\tdst %s/%s", ip_string, ip_mask);
1145 }
1146
1147 static void dump_target(struct ipt_entry *entry)
1148
1149 {
1150         struct xtables_target *xt_t;
1151         struct xt_entry_target *target;
1152
1153         target = ipt_get_target(entry);
1154
1155         if (!strcmp(target->u.user.name, IPT_STANDARD_TARGET)) {
1156                 struct xt_standard_target *t;
1157
1158                 t = (struct xt_standard_target *)target;
1159
1160                 switch (t->verdict) {
1161                 case XT_RETURN:
1162                         DBG("\ttarget RETURN");
1163                         break;
1164
1165                 case -NF_ACCEPT - 1:
1166                         DBG("\ttarget ACCEPT");
1167                         break;
1168
1169                 case -NF_DROP - 1:
1170                         DBG("\ttarget DROP");
1171                         break;
1172
1173                 case -NF_QUEUE - 1:
1174                         DBG("\ttarget QUEUE");
1175                         break;
1176
1177                 case -NF_STOP - 1:
1178                         DBG("\ttarget STOP");
1179                         break;
1180
1181                 default:
1182                         DBG("\tJUMP %u", t->verdict);
1183                         break;
1184                 }
1185
1186                 xt_t = xtables_find_target(IPT_STANDARD_TARGET,
1187                                                 XTF_LOAD_MUST_SUCCEED);
1188
1189                 if(xt_t->print != NULL)
1190                         xt_t->print(NULL, target, 1);
1191         } else {
1192                 xt_t = xtables_find_target(target->u.user.name, XTF_TRY_LOAD);
1193                 if (xt_t == NULL) {
1194                         DBG("\ttarget %s", target->u.user.name);
1195                         return;
1196                 }
1197
1198                 if(xt_t->print != NULL) {
1199                         DBG("\ttarget ");
1200                         xt_t->print(NULL, target, 1);
1201                 }
1202         }
1203 }
1204
1205 static void dump_match(struct ipt_entry *entry)
1206 {
1207         struct xtables_match *xt_m;
1208         struct xt_entry_match *match;
1209
1210         if (entry->elems == (unsigned char *)entry + entry->target_offset)
1211                 return;
1212
1213         match = (struct xt_entry_match *) entry->elems;
1214
1215         if (!strlen(match->u.user.name))
1216                 return;
1217
1218         xt_m = xtables_find_match(match->u.user.name, XTF_TRY_LOAD, NULL);
1219         if (xt_m == NULL)
1220                 goto out;
1221
1222         if(xt_m->print != NULL) {
1223                 DBG("\tmatch ");
1224                 xt_m->print(NULL, match, 1);
1225
1226                 return;
1227         }
1228
1229 out:
1230         DBG("\tmatch %s", match->u.user.name);
1231
1232 }
1233
1234 static int dump_entry(struct ipt_entry *entry, int builtin,
1235                         unsigned int hook, size_t size, unsigned int offset,
1236                         void *user_data)
1237 {
1238         struct xt_entry_target *target;
1239
1240         target = ipt_get_target(entry);
1241
1242         if (offset + entry->next_offset == size) {
1243                 DBG("\tEnd of CHAIN");
1244                 return 0;
1245         }
1246
1247         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET)) {
1248                 DBG("\tUSER CHAIN (%s) match %p  target %p",
1249                         target->data, entry->elems,
1250                         (char *)entry + entry->target_offset);
1251
1252                 return 0;
1253         } else if (builtin >= 0) {
1254                 DBG("\tCHAIN (%s) match %p  target %p",
1255                         hooknames[builtin], entry->elems,
1256                         (char *)entry + entry->target_offset);
1257         } else {
1258                 DBG("\tRULE  match %p  target %p",
1259                         entry->elems,
1260                         (char *)entry + entry->target_offset);
1261         }
1262
1263         dump_match(entry);
1264         dump_target(entry);
1265         dump_ip(entry);
1266
1267         return 0;
1268 }
1269
1270 static void dump_table(struct connman_iptables *table)
1271 {
1272         DBG("%s valid_hooks=0x%08x, num_entries=%u, size=%u",
1273                         table->info->name,
1274                         table->info->valid_hooks, table->info->num_entries,
1275                                 table->info->size);
1276
1277         DBG("entry hook: pre/in/fwd/out/post %d/%d/%d/%d/%d",
1278                 table->info->hook_entry[NF_IP_PRE_ROUTING],
1279                 table->info->hook_entry[NF_IP_LOCAL_IN],
1280                 table->info->hook_entry[NF_IP_FORWARD],
1281                 table->info->hook_entry[NF_IP_LOCAL_OUT],
1282                 table->info->hook_entry[NF_IP_POST_ROUTING]);
1283         DBG("underflow:  pre/in/fwd/out/post %d/%d/%d/%d/%d",
1284                 table->info->underflow[NF_IP_PRE_ROUTING],
1285                 table->info->underflow[NF_IP_LOCAL_IN],
1286                 table->info->underflow[NF_IP_FORWARD],
1287                 table->info->underflow[NF_IP_LOCAL_OUT],
1288                 table->info->underflow[NF_IP_POST_ROUTING]);
1289
1290         iterate_entries(table->blob_entries->entrytable,
1291                         table->info->valid_hooks,
1292                         table->info->hook_entry,
1293                         table->info->underflow,
1294                         table->blob_entries->size,
1295                         print_entry, dump_entry);
1296 }
1297
1298 static void dump_ipt_replace(struct ipt_replace *repl)
1299 {
1300         DBG("%s valid_hooks 0x%08x  num_entries %u  size %u",
1301                         repl->name, repl->valid_hooks, repl->num_entries,
1302                         repl->size);
1303
1304         DBG("entry hook: pre/in/fwd/out/post %d/%d/%d/%d/%d",
1305                 repl->hook_entry[NF_IP_PRE_ROUTING],
1306                 repl->hook_entry[NF_IP_LOCAL_IN],
1307                 repl->hook_entry[NF_IP_FORWARD],
1308                 repl->hook_entry[NF_IP_LOCAL_OUT],
1309                 repl->hook_entry[NF_IP_POST_ROUTING]);
1310         DBG("underflow:  pre/in/fwd/out/post %d/%d/%d/%d/%d",
1311                 repl->underflow[NF_IP_PRE_ROUTING],
1312                 repl->underflow[NF_IP_LOCAL_IN],
1313                 repl->underflow[NF_IP_FORWARD],
1314                 repl->underflow[NF_IP_LOCAL_OUT],
1315                 repl->underflow[NF_IP_POST_ROUTING]);
1316
1317         iterate_entries(repl->entries, repl->valid_hooks,
1318                         repl->hook_entry, repl->underflow,
1319                         repl->size, print_entry, dump_entry);
1320 }
1321
1322 static int iptables_get_entries(struct connman_iptables *table)
1323 {
1324         socklen_t entry_size;
1325
1326         entry_size = sizeof(struct ipt_get_entries) + table->info->size;
1327
1328         return getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_ENTRIES,
1329                                 table->blob_entries, &entry_size);
1330 }
1331
1332 static int iptables_replace(struct connman_iptables *table,
1333                                         struct ipt_replace *r)
1334 {
1335         return setsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_SET_REPLACE, r,
1336                          sizeof(*r) + r->size);
1337 }
1338
1339 static int add_entry(struct ipt_entry *entry, int builtin, unsigned int hook,
1340                         size_t size, unsigned offset, void *user_data)
1341 {
1342         struct connman_iptables *table = user_data;
1343         struct ipt_entry *new_entry;
1344
1345         new_entry = g_try_malloc0(entry->next_offset);
1346         if (new_entry == NULL)
1347                 return -ENOMEM;
1348
1349         memcpy(new_entry, entry, entry->next_offset);
1350
1351         return iptables_add_entry(table, new_entry, NULL, builtin);
1352 }
1353
1354 static void table_cleanup(struct connman_iptables *table)
1355 {
1356         GList *list;
1357         struct connman_iptables_entry *entry;
1358
1359         if (table == NULL)
1360                 return;
1361
1362         if (table->ipt_sock >= 0)
1363                 close(table->ipt_sock);
1364
1365         for (list = table->entries; list; list = list->next) {
1366                 entry = list->data;
1367
1368                 g_free(entry->entry);
1369                 g_free(entry);
1370         }
1371
1372         g_list_free(table->entries);
1373         g_free(table->info);
1374         g_free(table->blob_entries);
1375         g_free(table);
1376 }
1377
1378 static struct connman_iptables *iptables_init(const char *table_name)
1379 {
1380         struct connman_iptables *table = NULL;
1381         char *module = NULL;
1382         socklen_t s;
1383
1384         if (table_name == NULL)
1385                 table_name = "filter";
1386
1387         DBG("%s", table_name);
1388
1389         if (xtables_insmod("ip_tables", NULL, TRUE) != 0)
1390                 DBG("ip_tables module loading gives error but trying anyway");
1391
1392         module = g_strconcat("iptable_", table_name, NULL);
1393         if (module == NULL)
1394                 return NULL;
1395
1396         if (xtables_insmod(module, NULL, TRUE) != 0)
1397                 DBG("%s module loading gives error but trying anyway", module);
1398
1399         g_free(module);
1400
1401         table = g_hash_table_lookup(table_hash, table_name);
1402         if (table != NULL)
1403                 return table;
1404
1405         table = g_try_new0(struct connman_iptables, 1);
1406         if (table == NULL)
1407                 return NULL;
1408
1409         table->info = g_try_new0(struct ipt_getinfo, 1);
1410         if (table->info == NULL)
1411                 goto err;
1412
1413         table->ipt_sock = socket(AF_INET, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_RAW);
1414         if (table->ipt_sock < 0)
1415                 goto err;
1416
1417         s = sizeof(*table->info);
1418         strcpy(table->info->name, table_name);
1419         if (getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_INFO,
1420                                                 table->info, &s) < 0) {
1421                 connman_error("iptables support missing error %d (%s)", errno,
1422                         strerror(errno));
1423                 goto err;
1424         }
1425
1426         table->blob_entries = g_try_malloc0(sizeof(struct ipt_get_entries) +
1427                                                 table->info->size);
1428         if (table->blob_entries == NULL)
1429                 goto err;
1430
1431         strcpy(table->blob_entries->name, table_name);
1432         table->blob_entries->size = table->info->size;
1433
1434         if (iptables_get_entries(table) < 0)
1435                 goto err;
1436
1437         table->num_entries = 0;
1438         table->old_entries = table->info->num_entries;
1439         table->size = 0;
1440
1441         memcpy(table->underflow, table->info->underflow,
1442                                 sizeof(table->info->underflow));
1443         memcpy(table->hook_entry, table->info->hook_entry,
1444                                 sizeof(table->info->hook_entry));
1445
1446         iterate_entries(table->blob_entries->entrytable,
1447                         table->info->valid_hooks, table->info->hook_entry,
1448                         table->info->underflow, table->blob_entries->size,
1449                         add_entry, table);
1450
1451         g_hash_table_insert(table_hash, g_strdup(table_name), table);
1452
1453         if (debug_enabled == TRUE)
1454                 dump_table(table);
1455
1456         return table;
1457
1458 err:
1459         table_cleanup(table);
1460
1461         return NULL;
1462 }
1463
1464 static struct option iptables_opts[] = {
1465         {.name = "append",        .has_arg = 1, .val = 'A'},
1466         {.name = "compare",       .has_arg = 1, .val = 'C'},
1467         {.name = "delete",        .has_arg = 1, .val = 'D'},
1468         {.name = "flush-chain",   .has_arg = 1, .val = 'F'},
1469         {.name = "insert",        .has_arg = 1, .val = 'I'},
1470         {.name = "list",          .has_arg = 2, .val = 'L'},
1471         {.name = "new-chain",     .has_arg = 1, .val = 'N'},
1472         {.name = "policy",        .has_arg = 1, .val = 'P'},
1473         {.name = "delete-chain",  .has_arg = 1, .val = 'X'},
1474         {.name = "destination",   .has_arg = 1, .val = 'd'},
1475         {.name = "in-interface",  .has_arg = 1, .val = 'i'},
1476         {.name = "jump",          .has_arg = 1, .val = 'j'},
1477         {.name = "match",         .has_arg = 1, .val = 'm'},
1478         {.name = "out-interface", .has_arg = 1, .val = 'o'},
1479         {.name = "source",        .has_arg = 1, .val = 's'},
1480         {.name = "table",         .has_arg = 1, .val = 't'},
1481         {NULL},
1482 };
1483
1484 struct xtables_globals iptables_globals = {
1485         .option_offset = 0,
1486         .opts = iptables_opts,
1487         .orig_opts = iptables_opts,
1488 };
1489
1490 static struct xtables_target *prepare_target(struct connman_iptables *table,
1491                                                         const char *target_name)
1492 {
1493         struct xtables_target *xt_t = NULL;
1494         gboolean is_builtin, is_user_defined;
1495         GList *chain_head = NULL;
1496         size_t target_size;
1497
1498         is_builtin = FALSE;
1499         is_user_defined = FALSE;
1500
1501         if (is_builtin_target(target_name))
1502                 is_builtin = TRUE;
1503         else {
1504                 chain_head = find_chain_head(table, target_name);
1505                 if (chain_head != NULL && chain_head->next != NULL)
1506                         is_user_defined = TRUE;
1507         }
1508
1509         if (is_builtin || is_user_defined)
1510                 xt_t = xtables_find_target(IPT_STANDARD_TARGET,
1511                                                 XTF_LOAD_MUST_SUCCEED);
1512         else
1513                 xt_t = xtables_find_target(target_name, XTF_TRY_LOAD);
1514
1515         if (xt_t == NULL)
1516                 return NULL;
1517
1518         target_size = ALIGN(sizeof(struct ipt_entry_target)) + xt_t->size;
1519
1520         xt_t->t = g_try_malloc0(target_size);
1521         if (xt_t->t == NULL)
1522                 return NULL;
1523
1524         xt_t->t->u.target_size = target_size;
1525
1526         if (is_builtin || is_user_defined) {
1527                 struct xt_standard_target *target;
1528
1529                 target = (struct xt_standard_target *)(xt_t->t);
1530                 strcpy(target->target.u.user.name, IPT_STANDARD_TARGET);
1531
1532                 if (is_builtin == TRUE)
1533                         target->verdict = target_to_verdict(target_name);
1534                 else if (is_user_defined == TRUE) {
1535                         struct connman_iptables_entry *target_rule;
1536
1537                         if (chain_head == NULL) {
1538                                 g_free(xt_t->t);
1539                                 return NULL;
1540                         }
1541
1542                         target_rule = chain_head->next->data;
1543                         target->verdict = target_rule->offset;
1544                 }
1545         } else {
1546                 strcpy(xt_t->t->u.user.name, target_name);
1547                 xt_t->t->u.user.revision = xt_t->revision;
1548                 if (xt_t->init != NULL)
1549                         xt_t->init(xt_t->t);
1550         }
1551
1552 #if XTABLES_VERSION_CODE > 5
1553         if (xt_t->x6_options != NULL)
1554                 iptables_globals.opts =
1555                         xtables_options_xfrm(
1556                                 iptables_globals.orig_opts,
1557                                 iptables_globals.opts,
1558                                 xt_t->x6_options,
1559                                 &xt_t->option_offset);
1560         else
1561 #endif
1562                 iptables_globals.opts =
1563                         xtables_merge_options(
1564 #if XTABLES_VERSION_CODE > 5
1565                                 iptables_globals.orig_opts,
1566 #endif
1567                                 iptables_globals.opts,
1568                                 xt_t->extra_opts,
1569                                 &xt_t->option_offset);
1570
1571         if (iptables_globals.opts == NULL) {
1572                 g_free(xt_t->t);
1573                 xt_t = NULL;
1574         }
1575
1576         return xt_t;
1577 }
1578
1579 static struct xtables_match *prepare_matches(struct connman_iptables *table,
1580                                         struct xtables_rule_match **xt_rm,
1581                                         const char *match_name)
1582 {
1583         struct xtables_match *xt_m;
1584         size_t match_size;
1585
1586         if (match_name == NULL)
1587                 return NULL;
1588
1589         xt_m = xtables_find_match(match_name, XTF_LOAD_MUST_SUCCEED, xt_rm);
1590         match_size = ALIGN(sizeof(struct ipt_entry_match)) + xt_m->size;
1591
1592         xt_m->m = g_try_malloc0(match_size);
1593         if (xt_m->m == NULL)
1594                 return NULL;
1595
1596         xt_m->m->u.match_size = match_size;
1597         strcpy(xt_m->m->u.user.name, xt_m->name);
1598         xt_m->m->u.user.revision = xt_m->revision;
1599
1600         if (xt_m->init != NULL)
1601                 xt_m->init(xt_m->m);
1602
1603 #if XTABLES_VERSION_CODE > 5
1604         if (xt_m->x6_options != NULL)
1605                 iptables_globals.opts =
1606                         xtables_options_xfrm(
1607                                 iptables_globals.orig_opts,
1608                                 iptables_globals.opts,
1609                                 xt_m->x6_options,
1610                                 &xt_m->option_offset);
1611         else
1612 #endif
1613                         iptables_globals.opts =
1614                         xtables_merge_options(
1615 #if XTABLES_VERSION_CODE > 5
1616                                 iptables_globals.orig_opts,
1617 #endif
1618                                 iptables_globals.opts,
1619                                 xt_m->extra_opts,
1620                                 &xt_m->option_offset);
1621
1622         if (iptables_globals.opts == NULL) {
1623                 g_free(xt_m->m);
1624                 xt_m = NULL;
1625         }
1626
1627         return xt_m;
1628 }
1629
1630 static int parse_ip_and_mask(const char *str, struct in_addr *ip, struct in_addr *mask)
1631 {
1632         char **tokens;
1633         uint32_t prefixlength;
1634         uint32_t tmp;
1635         int err;
1636
1637         tokens = g_strsplit(str, "/", 2);
1638         if (tokens == NULL)
1639                 return -1;
1640
1641         if (!inet_pton(AF_INET, tokens[0], ip)) {
1642                 err = -1;
1643                 goto out;
1644         }
1645
1646         if (tokens[1] != NULL) {
1647                 prefixlength = strtol(tokens[1], NULL, 10);
1648                 if (prefixlength > 31) {
1649                         err = -1;
1650                         goto out;
1651                 }
1652
1653                 tmp = ~(0xffffffff >> prefixlength);
1654         } else {
1655                 tmp = 0xffffffff;
1656         }
1657
1658         mask->s_addr = htonl(tmp);
1659         ip->s_addr = ip->s_addr & mask->s_addr;
1660         err = 0;
1661 out:
1662         g_strfreev(tokens);
1663
1664         return err;
1665 }
1666
1667 static struct connman_iptables *pre_load_table(const char *table_name,
1668                                         struct connman_iptables *table)
1669 {
1670         if (table != NULL)
1671                 return table;
1672
1673         return iptables_init(table_name);
1674 }
1675
1676 struct parse_context {
1677         int argc;
1678         char **argv;
1679         struct ipt_ip *ip;
1680         struct xtables_target *xt_t;
1681         struct xtables_match *xt_m;
1682         struct xtables_rule_match *xt_rm;
1683 };
1684
1685 static int prepare_getopt_args(const char *str, struct parse_context *ctx)
1686 {
1687         char **tokens;
1688         int i;
1689
1690         tokens = g_strsplit_set(str, " ", -1);
1691
1692         i = g_strv_length(tokens);
1693
1694         /* Add space for the argv[0] value */
1695         ctx->argc = i + 1;
1696
1697         /* Don't forget the last NULL entry */
1698         ctx->argv = g_try_malloc0((ctx->argc + 1) * sizeof(char *));
1699         if (ctx->argv == NULL) {
1700                 g_strfreev(tokens);
1701                 return -ENOMEM;
1702         }
1703
1704         /*
1705          * getopt_long() jumps over the first token; we need to add some
1706          * random argv[0] entry.
1707          */
1708         ctx->argv[0] = g_strdup("argh");
1709         for (i = 1; i < ctx->argc; i++)
1710                 ctx->argv[i] = tokens[i - 1];
1711
1712         g_free(tokens);
1713
1714         return 0;
1715 }
1716
1717 #if XTABLES_VERSION_CODE > 5
1718
1719 static int parse_xt_modules(int c, connman_bool_t invert,
1720                                 struct parse_context *ctx)
1721 {
1722         struct xtables_match *m;
1723         struct xtables_rule_match *rm;
1724
1725         DBG("xtables version code > 5");
1726
1727         for (rm = ctx->xt_rm; rm != NULL; rm = rm->next) {
1728                 if (rm->completed != 0)
1729                         continue;
1730
1731                 m = rm->match;
1732
1733                 if (m->x6_parse == NULL && m->parse == NULL)
1734                         continue;
1735
1736                 if (c < (int) m->option_offset ||
1737                                 c >= (int) m->option_offset
1738                                         + XT_OPTION_OFFSET_SCALE)
1739                         continue;
1740
1741                 xtables_option_mpcall(c, ctx->argv, invert, m, NULL);
1742         }
1743
1744         if (ctx->xt_t == NULL)
1745                 return 0;
1746
1747         if (ctx->xt_t->x6_parse == NULL && ctx->xt_t->parse == NULL)
1748                 return 0;
1749
1750         if (c < (int) ctx->xt_t->option_offset ||
1751                         c >= (int) ctx->xt_t->option_offset
1752                                         + XT_OPTION_OFFSET_SCALE)
1753                 return 0;
1754
1755         xtables_option_tpcall(c, ctx->argv, invert, ctx->xt_t, NULL);
1756
1757         return 0;
1758 }
1759
1760 static int final_check_xt_modules(struct parse_context *ctx)
1761 {
1762         struct xtables_rule_match *rm;
1763
1764         DBG("xtables version code > 5");
1765
1766         for (rm = ctx->xt_rm; rm != NULL; rm = rm->next)
1767                 xtables_option_mfcall(rm->match);
1768
1769         if (ctx->xt_t != NULL)
1770                 xtables_option_tfcall(ctx->xt_t);
1771
1772         return 0;
1773 }
1774
1775 #else
1776
1777 static int parse_xt_modules(int c, connman_bool_t invert,
1778                                 struct parse_context *ctx)
1779 {
1780         struct xtables_match *m;
1781         struct xtables_rule_match *rm;
1782         int err;
1783
1784         DBG("xtables version code <= 5");
1785
1786         for (rm = ctx->xt_rm; rm != NULL; rm = rm->next) {
1787                 if (rm->completed == 1)
1788                         continue;
1789
1790                 m = rm->match;
1791
1792                 if (m->parse == NULL)
1793                         continue;
1794
1795                 err = m->parse(c - m->option_offset,
1796                                 argv, invert, &m->mflags,
1797                                 NULL, &m->m);
1798                 if (err > 0)
1799                         return -err;
1800         }
1801
1802         if (ctx->xt_t == NULL)
1803                 return 0;
1804
1805         if (ctx->xt_t->parse == NULL)
1806                 return 0;
1807
1808         err = ctx->xt_m->parse(c - ctx->xt_m->option_offset,
1809                                 ctx->argv, invert, &ctx->xt_m->mflags,
1810                                 NULL, &ctx->xt_m->m);
1811         return -err;
1812 }
1813
1814 static int final_check_xt_modules(struct parse_context *ctx)
1815 {
1816         struct xtables_rule_match *rm;
1817
1818         DBG("xtables version code <= 5");
1819
1820         for (rm = ctx->xt_rm; rm != NULL; rm = rm->next)
1821                 if (rm->match->final_check != NULL)
1822                         rm->match->final_check(rm->match->mflags);
1823
1824         if (ctx->xt_t != NULL && ctx->xt_t->final_check != NULL)
1825                 ctx->xt_t->final_check(ctx->xt_t->tflags);
1826
1827         return 0;
1828 }
1829
1830 #endif
1831
1832 static int parse_rule_spec(struct connman_iptables *table,
1833                                 struct parse_context *ctx)
1834 {
1835         /*
1836          * How the parser works:
1837          *
1838          *  - If getopt finds 's', 'd', 'i', 'o'.
1839          *    just extract the information.
1840          *  - if '!' is found, set the invert flag to true and
1841          *    removes the '!' from the optarg string and jumps
1842          *    back to getopt to reparse the current optarg string.
1843          *    After reparsing the invert flag is reseted to false.
1844          *  - If 'm' or 'j' is found then call either
1845          *    prepare_matches() or prepare_target(). Those function
1846          *    will modify (extend) the longopts for getopt_long.
1847          *    That means getopt will change its matching context according
1848          *    the loaded target.
1849          *
1850          *    Here an example with iptables-test
1851          *
1852          *    argv[0] = ./tools/iptables-test
1853          *    argv[1] = -t
1854          *    argv[2] = filter
1855          *    argv[3] = -A
1856          *    argv[4] = INPUT
1857          *    argv[5] = -m
1858          *    argv[6] = mark
1859          *    argv[7] = --mark
1860          *    argv[8] = 999
1861          *    argv[9] = -j
1862          *    argv[10] = LOG
1863          *
1864          *    getopt found 'm' then the optarg is "mark" and optind 7
1865          *    The longopts array containts before hitting the `case 'm'`
1866          *
1867          *    val A has_arg 1 name append
1868          *    val C has_arg 1 name compare
1869          *    val D has_arg 1 name delete
1870          *    val F has_arg 1 name flush-chain
1871          *    val I has_arg 1 name insert
1872          *    val L has_arg 2 name list
1873          *    val N has_arg 1 name new-chain
1874          *    val P has_arg 1 name policy
1875          *    val X has_arg 1 name delete-chain
1876          *    val d has_arg 1 name destination
1877          *    val i has_arg 1 name in-interface
1878          *    val j has_arg 1 name jump
1879          *    val m has_arg 1 name match
1880          *    val o has_arg 1 name out-interface
1881          *    val s has_arg 1 name source
1882          *    val t has_arg 1 name table
1883          *
1884          *    After executing the `case 'm'` block longopts is
1885          *
1886          *    val A has_arg 1 name append
1887          *    val C has_arg 1 name compare
1888          *    val D has_arg 1 name delete
1889          *    val F has_arg 1 name flush-chain
1890          *    val I has_arg 1 name insert
1891          *    val L has_arg 2 name list
1892          *    val N has_arg 1 name new-chain
1893          *    val P has_arg 1 name policy
1894          *    val X has_arg 1 name delete-chain
1895          *    val d has_arg 1 name destination
1896          *    val i has_arg 1 name in-interface
1897          *    val j has_arg 1 name jump
1898          *    val m has_arg 1 name match
1899          *    val o has_arg 1 name out-interface
1900          *    val s has_arg 1 name source
1901          *    val t has_arg 1 name table
1902          *    val   has_arg 1 name mark
1903          *
1904          *    So the 'mark' matcher has added the 'mark' options
1905          *    and getopt will then return c '256' optarg "999" optind 9
1906          *    And we will hit the 'default' statement which then
1907          *    will call the matchers parser (xt_m->parser() or
1908          *    xtables_option_mpcall() depending on which version
1909          *    of libxtables is found.
1910          */
1911         connman_bool_t invert = FALSE;
1912         int len, c, err;
1913
1914         DBG("");
1915
1916         ctx->ip = g_try_new0(struct ipt_ip, 1);
1917         if (ctx->ip == NULL)
1918                 return -ENOMEM;
1919
1920         /*
1921          * Tell getopt_long not to generate error messages for unknown
1922          * options and also reset optind back to 0.
1923          */
1924         opterr = 0;
1925         optind = 0;
1926
1927         while ((c = getopt_long(ctx->argc, ctx->argv,
1928                                         "-:d:i:o:s:m:j:",
1929                                         iptables_globals.opts, NULL)) != -1) {
1930                 switch (c) {
1931                 case 's':
1932                         /* Source specification */
1933                         if (!parse_ip_and_mask(optarg,
1934                                                 &ctx->ip->src,
1935                                                 &ctx->ip->smsk))
1936                                 break;
1937
1938                         if (invert)
1939                                 ctx->ip->invflags |= IPT_INV_SRCIP;
1940
1941                         break;
1942                 case 'd':
1943                         /* Destination specification */
1944                         if (!parse_ip_and_mask(optarg,
1945                                                 &ctx->ip->dst,
1946                                                 &ctx->ip->dmsk))
1947                                 break;
1948
1949                         if (invert)
1950                                 ctx->ip->invflags |= IPT_INV_DSTIP;
1951                         break;
1952                 case 'i':
1953                         /* In interface specification */
1954                         len = strlen(optarg);
1955
1956                         if (len + 1 > IFNAMSIZ)
1957                                 break;
1958
1959                         strcpy(ctx->ip->iniface, optarg);
1960                         memset(ctx->ip->iniface_mask, 0xff, len + 1);
1961
1962                         if (invert)
1963                                 ctx->ip->invflags |= IPT_INV_VIA_IN;
1964
1965                         break;
1966                 case 'o':
1967                         /* Out interface specification */
1968                         len = strlen(optarg);
1969
1970                         if (len + 1 > IFNAMSIZ)
1971                                 break;
1972
1973                         strcpy(ctx->ip->outiface, optarg);
1974                         memset(ctx->ip->outiface_mask, 0xff, len + 1);
1975
1976                         if (invert)
1977                                 ctx->ip->invflags |= IPT_INV_VIA_OUT;
1978
1979                         break;
1980                 case 'm':
1981                         /* Matches */
1982                         ctx->xt_m = prepare_matches(table, &ctx->xt_rm, optarg);
1983                         if (ctx->xt_m == NULL) {
1984                                 err = -EINVAL;
1985                                 goto out;
1986                         }
1987
1988                         break;
1989                 case 'j':
1990                         /* Target */
1991                         ctx->xt_t = prepare_target(table, optarg);
1992                         if (ctx->xt_t == NULL) {
1993                                 err = -EINVAL;
1994                                 goto out;
1995                         }
1996
1997                         break;
1998                 case 1:
1999                         if (optarg[0] == '!' && optarg[1] == '\0') {
2000                                 invert = TRUE;
2001
2002                                 /* Remove the '!' from the optarg */
2003                                 optarg[0] = '\0';
2004
2005                                 /*
2006                                  * And recall getopt_long without reseting
2007                                  * invert.
2008                                  */
2009                                 continue;
2010                         }
2011
2012                         break;
2013                 default:
2014                         err = parse_xt_modules(c, invert, ctx);
2015                         if (err == 1)
2016                                 continue;
2017
2018                         break;
2019                 }
2020
2021                 invert = FALSE;
2022         }
2023
2024         err = final_check_xt_modules(ctx);
2025
2026 out:
2027         return err;
2028 }
2029
2030 static void reset_xtables(void)
2031 {
2032         struct xtables_match *xt_m;
2033         struct xtables_target *xt_t;
2034
2035         /*
2036          * As side effect parsing a rule sets some global flags
2037          * which will be evaluated/verified. Let's reset them
2038          * to ensure we can parse more than one rule.
2039          *
2040          * Clear all flags because the flags are only valid
2041          * for one rule.
2042          */
2043         for (xt_m = xtables_matches; xt_m != NULL; xt_m = xt_m->next)
2044                 xt_m->mflags = 0;
2045
2046         for (xt_t = xtables_targets; xt_t != NULL; xt_t = xt_t->next) {
2047                 xt_t->tflags = 0;
2048                 xt_t->used = 0;
2049         }
2050
2051         /*
2052          * We need also to free the memory implicitly allocated
2053          * during parsing (see xtables_options_xfrm()).
2054          * Note xt_params is actually iptables_globals.
2055          */
2056         if (xt_params->opts != xt_params->orig_opts) {
2057                 g_free(xt_params->opts);
2058                 xt_params->opts = xt_params->orig_opts;
2059         }
2060         xt_params->option_offset = 0;
2061 }
2062
2063 static void cleanup_parse_context(struct parse_context *ctx)
2064 {
2065         struct xtables_rule_match *rm, *tmp;
2066
2067         g_strfreev(ctx->argv);
2068         g_free(ctx->ip);
2069         if (ctx->xt_t != NULL) {
2070                 g_free(ctx->xt_t->t);
2071                 ctx->xt_t->t = NULL;
2072         }
2073         if (ctx->xt_m != NULL) {
2074                 g_free(ctx->xt_m->m);
2075                 ctx->xt_m->m = NULL;
2076         }
2077         for (tmp = NULL, rm = ctx->xt_rm; rm != NULL; rm = rm->next) {
2078                 if (tmp != NULL)
2079                         g_free(tmp);
2080                 tmp = rm;
2081         }
2082         g_free(tmp);
2083
2084         g_free(ctx);
2085 }
2086
2087 int __connman_iptables_new_chain(const char *table_name,
2088                                         const char *chain)
2089 {
2090         struct connman_iptables *table;
2091
2092         DBG("-t %s -N %s", table_name, chain);
2093
2094         table = pre_load_table(table_name, NULL);
2095         if (table == NULL)
2096                 return -EINVAL;
2097
2098         return iptables_add_chain(table, chain);
2099 }
2100
2101 int __connman_iptables_delete_chain(const char *table_name,
2102                                         const char *chain)
2103 {
2104         struct connman_iptables *table;
2105
2106         DBG("-t %s -X %s", table_name, chain);
2107
2108         table = pre_load_table(table_name, NULL);
2109         if (table == NULL)
2110                 return -EINVAL;
2111
2112         return iptables_delete_chain(table, chain);
2113 }
2114
2115 int __connman_iptables_flush_chain(const char *table_name,
2116                                         const char *chain)
2117 {
2118         struct connman_iptables *table;
2119
2120         DBG("-t %s -F %s", table_name, chain);
2121
2122         table = pre_load_table(table_name, NULL);
2123         if (table == NULL)
2124                 return -EINVAL;
2125
2126         return iptables_flush_chain(table, chain);
2127 }
2128
2129 int __connman_iptables_change_policy(const char *table_name,
2130                                         const char *chain,
2131                                         const char *policy)
2132 {
2133         struct connman_iptables *table;
2134
2135         DBG("-t %s -F %s", table_name, chain);
2136
2137         table = pre_load_table(table_name, NULL);
2138         if (table == NULL)
2139                 return -EINVAL;
2140
2141         return iptables_change_policy(table, chain, policy);
2142 }
2143
2144 int __connman_iptables_append(const char *table_name,
2145                                 const char *chain,
2146                                 const char *rule_spec)
2147 {
2148         struct connman_iptables *table;
2149         struct parse_context *ctx;
2150         const char *target_name;
2151         int err;
2152
2153         ctx = g_try_new0(struct parse_context, 1);
2154         if (ctx == NULL)
2155                 return -ENOMEM;
2156
2157         DBG("-t %s -A %s %s", table_name, chain, rule_spec);
2158
2159         err = prepare_getopt_args(rule_spec, ctx);
2160         if (err < 0)
2161                 goto out;
2162
2163         table = pre_load_table(table_name, NULL);
2164         if (table == NULL) {
2165                 err = -EINVAL;
2166                 goto out;
2167         }
2168
2169         err = parse_rule_spec(table, ctx);
2170         if (err < 0)
2171                 goto out;
2172
2173         if (ctx->xt_t == NULL)
2174                 target_name = NULL;
2175         else
2176                 target_name = ctx->xt_t->name;
2177
2178         err = iptables_insert_rule(table, ctx->ip, chain,
2179                                 target_name, ctx->xt_t, ctx->xt_rm);
2180 out:
2181         cleanup_parse_context(ctx);
2182         reset_xtables();
2183
2184         return err;
2185 }
2186
2187 int __connman_iptables_delete(const char *table_name,
2188                                 const char *chain,
2189                                 const char *rule_spec)
2190 {
2191         struct connman_iptables *table;
2192         struct parse_context *ctx;
2193         const char *target_name;
2194         int err;
2195
2196         ctx = g_try_new0(struct parse_context, 1);
2197         if (ctx == NULL)
2198                 return -ENOMEM;
2199
2200         DBG("-t %s -D %s %s", table_name, chain, rule_spec);
2201
2202         err = prepare_getopt_args(rule_spec, ctx);
2203         if (err < 0)
2204                 goto out;
2205
2206         table = pre_load_table(table_name, NULL);
2207         if (table == NULL) {
2208                 err = -EINVAL;
2209                 goto out;
2210         }
2211
2212         err = parse_rule_spec(table, ctx);
2213         if (err < 0)
2214                 goto out;
2215
2216         if (ctx->xt_t == NULL)
2217                 target_name = NULL;
2218         else
2219                 target_name = ctx->xt_t->name;
2220
2221         err = iptables_delete_rule(table, ctx->ip, chain,
2222                                 target_name, ctx->xt_t, ctx->xt_m,
2223                                 ctx->xt_rm);
2224 out:
2225         cleanup_parse_context(ctx);
2226         reset_xtables();
2227
2228         return err;
2229 }
2230
2231 int __connman_iptables_commit(const char *table_name)
2232 {
2233         struct connman_iptables *table;
2234         struct ipt_replace *repl;
2235         int err;
2236
2237         DBG("%s", table_name);
2238
2239         table = g_hash_table_lookup(table_hash, table_name);
2240         if (table == NULL)
2241                 return -EINVAL;
2242
2243         repl = iptables_blob(table);
2244
2245         if (debug_enabled == TRUE)
2246                 dump_ipt_replace(repl);
2247
2248         err = iptables_replace(table, repl);
2249
2250         g_free(repl->counters);
2251         g_free(repl);
2252
2253         if (err < 0)
2254             return err;
2255
2256         g_hash_table_remove(table_hash, table_name);
2257
2258         return 0;
2259 }
2260
2261 static void remove_table(gpointer user_data)
2262 {
2263         struct connman_iptables *table = user_data;
2264
2265         table_cleanup(table);
2266 }
2267
2268 static int flush_table_cb(struct ipt_entry *entry, int builtin,
2269                                 unsigned int hook, size_t size,
2270                                 unsigned int offset, void *user_data)
2271 {
2272         GSList **chains = user_data;
2273         struct xt_entry_target *target;
2274         char *name;
2275
2276         if (offset + entry->next_offset == size)
2277                 return 0;
2278
2279         target = ipt_get_target(entry);
2280
2281         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET))
2282                 name = g_strdup((const char*)target->data);
2283         else if (builtin >= 0)
2284                   name = g_strdup(hooknames[builtin]);
2285         else
2286                 return 0;
2287
2288         *chains = g_slist_prepend(*chains, name);
2289
2290         return 0;
2291 }
2292
2293 void flush_table(const char *name)
2294 {
2295         GSList *chains = NULL, *list;
2296         struct connman_iptables *table;
2297
2298         table = pre_load_table(name, NULL);
2299         if (table == NULL)
2300                 return;
2301
2302         iterate_entries(table->blob_entries->entrytable,
2303                         table->info->valid_hooks,
2304                         table->info->hook_entry,
2305                         table->info->underflow,
2306                         table->blob_entries->size,
2307                         flush_table_cb, &chains);
2308
2309
2310         /*
2311          * The offset update code is fragile and it works
2312          * only safe if we remove elements and move forwards
2313          * in the table.
2314          */
2315         chains = g_slist_reverse(chains);
2316
2317         for (list = chains; list != NULL; list = list->next) {
2318                 char *chain = list->data;
2319
2320                 DBG("chain %s", chain);
2321                 iptables_flush_chain(table, chain);
2322         }
2323
2324         __connman_iptables_commit(name);
2325         g_slist_free_full(chains, g_free);
2326 }
2327
2328 int __connman_iptables_init(void)
2329 {
2330         DBG("");
2331
2332         if (getenv("CONNMAN_IPTABLES_DEBUG"))
2333                 debug_enabled = TRUE;
2334
2335         table_hash = g_hash_table_new_full(g_str_hash, g_str_equal,
2336                                                 g_free, remove_table);
2337
2338         xtables_init_all(&iptables_globals, NFPROTO_IPV4);
2339
2340         return 0;
2341 }
2342
2343 void __connman_iptables_cleanup(void)
2344 {
2345         DBG("");
2346
2347         g_hash_table_destroy(table_hash);
2348 }