iptables: Fix setting policy
[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, *chain_tail;
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         chain_tail = find_chain_tail(table, chain_name);
1076         if (chain_tail == NULL)
1077                 return -EINVAL;
1078
1079         entry = chain_tail->prev->data;
1080         target = ipt_get_target(entry->entry);
1081
1082         t = (struct xt_standard_target *)target;
1083         t->verdict = verdict;
1084
1085         return 0;
1086 }
1087
1088 static struct ipt_replace *iptables_blob(struct connman_iptables *table)
1089 {
1090         struct ipt_replace *r;
1091         GList *list;
1092         struct connman_iptables_entry *e;
1093         unsigned char *entry_index;
1094
1095         r = g_try_malloc0(sizeof(struct ipt_replace) + table->size);
1096         if (r == NULL)
1097                 return NULL;
1098
1099         memset(r, 0, sizeof(*r) + table->size);
1100
1101         r->counters = g_try_malloc0(sizeof(struct xt_counters)
1102                                 * table->old_entries);
1103         if (r->counters == NULL) {
1104                 g_free(r);
1105                 return NULL;
1106         }
1107
1108         strcpy(r->name, table->info->name);
1109         r->num_entries = table->num_entries;
1110         r->size = table->size;
1111
1112         r->num_counters = table->old_entries;
1113         r->valid_hooks  = table->info->valid_hooks;
1114
1115         memcpy(r->hook_entry, table->hook_entry, sizeof(table->hook_entry));
1116         memcpy(r->underflow, table->underflow, sizeof(table->underflow));
1117
1118         entry_index = (unsigned char *)r->entries;
1119         for (list = table->entries; list; list = list->next) {
1120                 e = list->data;
1121
1122                 memcpy(entry_index, e->entry, e->entry->next_offset);
1123                 entry_index += e->entry->next_offset;
1124         }
1125
1126         return r;
1127 }
1128
1129 static void dump_ip(struct ipt_entry *entry)
1130 {
1131         struct ipt_ip *ip = &entry->ip;
1132         char ip_string[INET6_ADDRSTRLEN];
1133         char ip_mask[INET6_ADDRSTRLEN];
1134
1135         if (strlen(ip->iniface))
1136                 DBG("\tin %s", ip->iniface);
1137
1138         if (strlen(ip->outiface))
1139                 DBG("\tout %s", ip->outiface);
1140
1141         if (inet_ntop(AF_INET, &ip->src, ip_string, INET6_ADDRSTRLEN) != NULL &&
1142                         inet_ntop(AF_INET, &ip->smsk,
1143                                         ip_mask, INET6_ADDRSTRLEN) != NULL)
1144                 DBG("\tsrc %s/%s", ip_string, ip_mask);
1145
1146         if (inet_ntop(AF_INET, &ip->dst, ip_string, INET6_ADDRSTRLEN) != NULL &&
1147                         inet_ntop(AF_INET, &ip->dmsk,
1148                                         ip_mask, INET6_ADDRSTRLEN) != NULL)
1149                 DBG("\tdst %s/%s", ip_string, ip_mask);
1150 }
1151
1152 static void dump_target(struct ipt_entry *entry)
1153
1154 {
1155         struct xtables_target *xt_t;
1156         struct xt_entry_target *target;
1157
1158         target = ipt_get_target(entry);
1159
1160         if (!strcmp(target->u.user.name, IPT_STANDARD_TARGET)) {
1161                 struct xt_standard_target *t;
1162
1163                 t = (struct xt_standard_target *)target;
1164
1165                 switch (t->verdict) {
1166                 case XT_RETURN:
1167                         DBG("\ttarget RETURN");
1168                         break;
1169
1170                 case -NF_ACCEPT - 1:
1171                         DBG("\ttarget ACCEPT");
1172                         break;
1173
1174                 case -NF_DROP - 1:
1175                         DBG("\ttarget DROP");
1176                         break;
1177
1178                 case -NF_QUEUE - 1:
1179                         DBG("\ttarget QUEUE");
1180                         break;
1181
1182                 case -NF_STOP - 1:
1183                         DBG("\ttarget STOP");
1184                         break;
1185
1186                 default:
1187                         DBG("\tJUMP %u", t->verdict);
1188                         break;
1189                 }
1190
1191                 xt_t = xtables_find_target(IPT_STANDARD_TARGET,
1192                                                 XTF_LOAD_MUST_SUCCEED);
1193
1194                 if(xt_t->print != NULL)
1195                         xt_t->print(NULL, target, 1);
1196         } else {
1197                 xt_t = xtables_find_target(target->u.user.name, XTF_TRY_LOAD);
1198                 if (xt_t == NULL) {
1199                         DBG("\ttarget %s", target->u.user.name);
1200                         return;
1201                 }
1202
1203                 if(xt_t->print != NULL) {
1204                         DBG("\ttarget ");
1205                         xt_t->print(NULL, target, 1);
1206                 }
1207         }
1208 }
1209
1210 static void dump_match(struct ipt_entry *entry)
1211 {
1212         struct xtables_match *xt_m;
1213         struct xt_entry_match *match;
1214
1215         if (entry->elems == (unsigned char *)entry + entry->target_offset)
1216                 return;
1217
1218         match = (struct xt_entry_match *) entry->elems;
1219
1220         if (!strlen(match->u.user.name))
1221                 return;
1222
1223         xt_m = xtables_find_match(match->u.user.name, XTF_TRY_LOAD, NULL);
1224         if (xt_m == NULL)
1225                 goto out;
1226
1227         if(xt_m->print != NULL) {
1228                 DBG("\tmatch ");
1229                 xt_m->print(NULL, match, 1);
1230
1231                 return;
1232         }
1233
1234 out:
1235         DBG("\tmatch %s", match->u.user.name);
1236
1237 }
1238
1239 static int dump_entry(struct ipt_entry *entry, int builtin,
1240                         unsigned int hook, size_t size, unsigned int offset,
1241                         void *user_data)
1242 {
1243         struct xt_entry_target *target;
1244
1245         target = ipt_get_target(entry);
1246
1247         if (offset + entry->next_offset == size) {
1248                 DBG("\tEnd of CHAIN");
1249                 return 0;
1250         }
1251
1252         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET)) {
1253                 DBG("\tUSER CHAIN (%s) match %p  target %p",
1254                         target->data, entry->elems,
1255                         (char *)entry + entry->target_offset);
1256
1257                 return 0;
1258         } else if (builtin >= 0) {
1259                 DBG("\tCHAIN (%s) match %p  target %p",
1260                         hooknames[builtin], entry->elems,
1261                         (char *)entry + entry->target_offset);
1262         } else {
1263                 DBG("\tRULE  match %p  target %p",
1264                         entry->elems,
1265                         (char *)entry + entry->target_offset);
1266         }
1267
1268         dump_match(entry);
1269         dump_target(entry);
1270         dump_ip(entry);
1271
1272         return 0;
1273 }
1274
1275 static void dump_table(struct connman_iptables *table)
1276 {
1277         DBG("%s valid_hooks=0x%08x, num_entries=%u, size=%u",
1278                         table->info->name,
1279                         table->info->valid_hooks, table->info->num_entries,
1280                                 table->info->size);
1281
1282         DBG("entry hook: pre/in/fwd/out/post %d/%d/%d/%d/%d",
1283                 table->info->hook_entry[NF_IP_PRE_ROUTING],
1284                 table->info->hook_entry[NF_IP_LOCAL_IN],
1285                 table->info->hook_entry[NF_IP_FORWARD],
1286                 table->info->hook_entry[NF_IP_LOCAL_OUT],
1287                 table->info->hook_entry[NF_IP_POST_ROUTING]);
1288         DBG("underflow:  pre/in/fwd/out/post %d/%d/%d/%d/%d",
1289                 table->info->underflow[NF_IP_PRE_ROUTING],
1290                 table->info->underflow[NF_IP_LOCAL_IN],
1291                 table->info->underflow[NF_IP_FORWARD],
1292                 table->info->underflow[NF_IP_LOCAL_OUT],
1293                 table->info->underflow[NF_IP_POST_ROUTING]);
1294
1295         iterate_entries(table->blob_entries->entrytable,
1296                         table->info->valid_hooks,
1297                         table->info->hook_entry,
1298                         table->info->underflow,
1299                         table->blob_entries->size,
1300                         print_entry, dump_entry);
1301 }
1302
1303 static void dump_ipt_replace(struct ipt_replace *repl)
1304 {
1305         DBG("%s valid_hooks 0x%08x  num_entries %u  size %u",
1306                         repl->name, repl->valid_hooks, repl->num_entries,
1307                         repl->size);
1308
1309         DBG("entry hook: pre/in/fwd/out/post %d/%d/%d/%d/%d",
1310                 repl->hook_entry[NF_IP_PRE_ROUTING],
1311                 repl->hook_entry[NF_IP_LOCAL_IN],
1312                 repl->hook_entry[NF_IP_FORWARD],
1313                 repl->hook_entry[NF_IP_LOCAL_OUT],
1314                 repl->hook_entry[NF_IP_POST_ROUTING]);
1315         DBG("underflow:  pre/in/fwd/out/post %d/%d/%d/%d/%d",
1316                 repl->underflow[NF_IP_PRE_ROUTING],
1317                 repl->underflow[NF_IP_LOCAL_IN],
1318                 repl->underflow[NF_IP_FORWARD],
1319                 repl->underflow[NF_IP_LOCAL_OUT],
1320                 repl->underflow[NF_IP_POST_ROUTING]);
1321
1322         iterate_entries(repl->entries, repl->valid_hooks,
1323                         repl->hook_entry, repl->underflow,
1324                         repl->size, print_entry, dump_entry);
1325 }
1326
1327 static int iptables_get_entries(struct connman_iptables *table)
1328 {
1329         socklen_t entry_size;
1330
1331         entry_size = sizeof(struct ipt_get_entries) + table->info->size;
1332
1333         return getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_ENTRIES,
1334                                 table->blob_entries, &entry_size);
1335 }
1336
1337 static int iptables_replace(struct connman_iptables *table,
1338                                         struct ipt_replace *r)
1339 {
1340         return setsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_SET_REPLACE, r,
1341                          sizeof(*r) + r->size);
1342 }
1343
1344 static int add_entry(struct ipt_entry *entry, int builtin, unsigned int hook,
1345                         size_t size, unsigned offset, void *user_data)
1346 {
1347         struct connman_iptables *table = user_data;
1348         struct ipt_entry *new_entry;
1349
1350         new_entry = g_try_malloc0(entry->next_offset);
1351         if (new_entry == NULL)
1352                 return -ENOMEM;
1353
1354         memcpy(new_entry, entry, entry->next_offset);
1355
1356         return iptables_add_entry(table, new_entry, NULL, builtin);
1357 }
1358
1359 static void table_cleanup(struct connman_iptables *table)
1360 {
1361         GList *list;
1362         struct connman_iptables_entry *entry;
1363
1364         if (table == NULL)
1365                 return;
1366
1367         if (table->ipt_sock >= 0)
1368                 close(table->ipt_sock);
1369
1370         for (list = table->entries; list; list = list->next) {
1371                 entry = list->data;
1372
1373                 g_free(entry->entry);
1374                 g_free(entry);
1375         }
1376
1377         g_list_free(table->entries);
1378         g_free(table->info);
1379         g_free(table->blob_entries);
1380         g_free(table);
1381 }
1382
1383 static struct connman_iptables *iptables_init(const char *table_name)
1384 {
1385         struct connman_iptables *table = NULL;
1386         char *module = NULL;
1387         socklen_t s;
1388
1389         if (table_name == NULL)
1390                 table_name = "filter";
1391
1392         DBG("%s", table_name);
1393
1394         if (xtables_insmod("ip_tables", NULL, TRUE) != 0)
1395                 DBG("ip_tables module loading gives error but trying anyway");
1396
1397         module = g_strconcat("iptable_", table_name, NULL);
1398         if (module == NULL)
1399                 return NULL;
1400
1401         if (xtables_insmod(module, NULL, TRUE) != 0)
1402                 DBG("%s module loading gives error but trying anyway", module);
1403
1404         g_free(module);
1405
1406         table = g_hash_table_lookup(table_hash, table_name);
1407         if (table != NULL)
1408                 return table;
1409
1410         table = g_try_new0(struct connman_iptables, 1);
1411         if (table == NULL)
1412                 return NULL;
1413
1414         table->info = g_try_new0(struct ipt_getinfo, 1);
1415         if (table->info == NULL)
1416                 goto err;
1417
1418         table->ipt_sock = socket(AF_INET, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_RAW);
1419         if (table->ipt_sock < 0)
1420                 goto err;
1421
1422         s = sizeof(*table->info);
1423         strcpy(table->info->name, table_name);
1424         if (getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_INFO,
1425                                                 table->info, &s) < 0) {
1426                 connman_error("iptables support missing error %d (%s)", errno,
1427                         strerror(errno));
1428                 goto err;
1429         }
1430
1431         table->blob_entries = g_try_malloc0(sizeof(struct ipt_get_entries) +
1432                                                 table->info->size);
1433         if (table->blob_entries == NULL)
1434                 goto err;
1435
1436         strcpy(table->blob_entries->name, table_name);
1437         table->blob_entries->size = table->info->size;
1438
1439         if (iptables_get_entries(table) < 0)
1440                 goto err;
1441
1442         table->num_entries = 0;
1443         table->old_entries = table->info->num_entries;
1444         table->size = 0;
1445
1446         memcpy(table->underflow, table->info->underflow,
1447                                 sizeof(table->info->underflow));
1448         memcpy(table->hook_entry, table->info->hook_entry,
1449                                 sizeof(table->info->hook_entry));
1450
1451         iterate_entries(table->blob_entries->entrytable,
1452                         table->info->valid_hooks, table->info->hook_entry,
1453                         table->info->underflow, table->blob_entries->size,
1454                         add_entry, table);
1455
1456         g_hash_table_insert(table_hash, g_strdup(table_name), table);
1457
1458         if (debug_enabled == TRUE)
1459                 dump_table(table);
1460
1461         return table;
1462
1463 err:
1464         table_cleanup(table);
1465
1466         return NULL;
1467 }
1468
1469 static struct option iptables_opts[] = {
1470         {.name = "append",        .has_arg = 1, .val = 'A'},
1471         {.name = "compare",       .has_arg = 1, .val = 'C'},
1472         {.name = "delete",        .has_arg = 1, .val = 'D'},
1473         {.name = "flush-chain",   .has_arg = 1, .val = 'F'},
1474         {.name = "insert",        .has_arg = 1, .val = 'I'},
1475         {.name = "list",          .has_arg = 2, .val = 'L'},
1476         {.name = "new-chain",     .has_arg = 1, .val = 'N'},
1477         {.name = "policy",        .has_arg = 1, .val = 'P'},
1478         {.name = "delete-chain",  .has_arg = 1, .val = 'X'},
1479         {.name = "destination",   .has_arg = 1, .val = 'd'},
1480         {.name = "in-interface",  .has_arg = 1, .val = 'i'},
1481         {.name = "jump",          .has_arg = 1, .val = 'j'},
1482         {.name = "match",         .has_arg = 1, .val = 'm'},
1483         {.name = "out-interface", .has_arg = 1, .val = 'o'},
1484         {.name = "source",        .has_arg = 1, .val = 's'},
1485         {.name = "table",         .has_arg = 1, .val = 't'},
1486         {NULL},
1487 };
1488
1489 struct xtables_globals iptables_globals = {
1490         .option_offset = 0,
1491         .opts = iptables_opts,
1492         .orig_opts = iptables_opts,
1493 };
1494
1495 static struct xtables_target *prepare_target(struct connman_iptables *table,
1496                                                         const char *target_name)
1497 {
1498         struct xtables_target *xt_t = NULL;
1499         gboolean is_builtin, is_user_defined;
1500         GList *chain_head = NULL;
1501         size_t target_size;
1502
1503         is_builtin = FALSE;
1504         is_user_defined = FALSE;
1505
1506         if (is_builtin_target(target_name))
1507                 is_builtin = TRUE;
1508         else {
1509                 chain_head = find_chain_head(table, target_name);
1510                 if (chain_head != NULL && chain_head->next != NULL)
1511                         is_user_defined = TRUE;
1512         }
1513
1514         if (is_builtin || is_user_defined)
1515                 xt_t = xtables_find_target(IPT_STANDARD_TARGET,
1516                                                 XTF_LOAD_MUST_SUCCEED);
1517         else
1518                 xt_t = xtables_find_target(target_name, XTF_TRY_LOAD);
1519
1520         if (xt_t == NULL)
1521                 return NULL;
1522
1523         target_size = ALIGN(sizeof(struct ipt_entry_target)) + xt_t->size;
1524
1525         xt_t->t = g_try_malloc0(target_size);
1526         if (xt_t->t == NULL)
1527                 return NULL;
1528
1529         xt_t->t->u.target_size = target_size;
1530
1531         if (is_builtin || is_user_defined) {
1532                 struct xt_standard_target *target;
1533
1534                 target = (struct xt_standard_target *)(xt_t->t);
1535                 strcpy(target->target.u.user.name, IPT_STANDARD_TARGET);
1536
1537                 if (is_builtin == TRUE)
1538                         target->verdict = target_to_verdict(target_name);
1539                 else if (is_user_defined == TRUE) {
1540                         struct connman_iptables_entry *target_rule;
1541
1542                         if (chain_head == NULL) {
1543                                 g_free(xt_t->t);
1544                                 return NULL;
1545                         }
1546
1547                         target_rule = chain_head->next->data;
1548                         target->verdict = target_rule->offset;
1549                 }
1550         } else {
1551                 strcpy(xt_t->t->u.user.name, target_name);
1552                 xt_t->t->u.user.revision = xt_t->revision;
1553                 if (xt_t->init != NULL)
1554                         xt_t->init(xt_t->t);
1555         }
1556
1557 #if XTABLES_VERSION_CODE > 5
1558         if (xt_t->x6_options != NULL)
1559                 iptables_globals.opts =
1560                         xtables_options_xfrm(
1561                                 iptables_globals.orig_opts,
1562                                 iptables_globals.opts,
1563                                 xt_t->x6_options,
1564                                 &xt_t->option_offset);
1565         else
1566 #endif
1567                 iptables_globals.opts =
1568                         xtables_merge_options(
1569 #if XTABLES_VERSION_CODE > 5
1570                                 iptables_globals.orig_opts,
1571 #endif
1572                                 iptables_globals.opts,
1573                                 xt_t->extra_opts,
1574                                 &xt_t->option_offset);
1575
1576         if (iptables_globals.opts == NULL) {
1577                 g_free(xt_t->t);
1578                 xt_t = NULL;
1579         }
1580
1581         return xt_t;
1582 }
1583
1584 static struct xtables_match *prepare_matches(struct connman_iptables *table,
1585                                         struct xtables_rule_match **xt_rm,
1586                                         const char *match_name)
1587 {
1588         struct xtables_match *xt_m;
1589         size_t match_size;
1590
1591         if (match_name == NULL)
1592                 return NULL;
1593
1594         xt_m = xtables_find_match(match_name, XTF_LOAD_MUST_SUCCEED, xt_rm);
1595         match_size = ALIGN(sizeof(struct ipt_entry_match)) + xt_m->size;
1596
1597         xt_m->m = g_try_malloc0(match_size);
1598         if (xt_m->m == NULL)
1599                 return NULL;
1600
1601         xt_m->m->u.match_size = match_size;
1602         strcpy(xt_m->m->u.user.name, xt_m->name);
1603         xt_m->m->u.user.revision = xt_m->revision;
1604
1605         if (xt_m->init != NULL)
1606                 xt_m->init(xt_m->m);
1607
1608 #if XTABLES_VERSION_CODE > 5
1609         if (xt_m->x6_options != NULL)
1610                 iptables_globals.opts =
1611                         xtables_options_xfrm(
1612                                 iptables_globals.orig_opts,
1613                                 iptables_globals.opts,
1614                                 xt_m->x6_options,
1615                                 &xt_m->option_offset);
1616         else
1617 #endif
1618                         iptables_globals.opts =
1619                         xtables_merge_options(
1620 #if XTABLES_VERSION_CODE > 5
1621                                 iptables_globals.orig_opts,
1622 #endif
1623                                 iptables_globals.opts,
1624                                 xt_m->extra_opts,
1625                                 &xt_m->option_offset);
1626
1627         if (iptables_globals.opts == NULL) {
1628                 g_free(xt_m->m);
1629                 xt_m = NULL;
1630         }
1631
1632         return xt_m;
1633 }
1634
1635 static int parse_ip_and_mask(const char *str, struct in_addr *ip, struct in_addr *mask)
1636 {
1637         char **tokens;
1638         uint32_t prefixlength;
1639         uint32_t tmp;
1640         int err;
1641
1642         tokens = g_strsplit(str, "/", 2);
1643         if (tokens == NULL)
1644                 return -1;
1645
1646         if (!inet_pton(AF_INET, tokens[0], ip)) {
1647                 err = -1;
1648                 goto out;
1649         }
1650
1651         if (tokens[1] != NULL) {
1652                 prefixlength = strtol(tokens[1], NULL, 10);
1653                 if (prefixlength > 31) {
1654                         err = -1;
1655                         goto out;
1656                 }
1657
1658                 tmp = ~(0xffffffff >> prefixlength);
1659         } else {
1660                 tmp = 0xffffffff;
1661         }
1662
1663         mask->s_addr = htonl(tmp);
1664         ip->s_addr = ip->s_addr & mask->s_addr;
1665         err = 0;
1666 out:
1667         g_strfreev(tokens);
1668
1669         return err;
1670 }
1671
1672 static struct connman_iptables *pre_load_table(const char *table_name,
1673                                         struct connman_iptables *table)
1674 {
1675         if (table != NULL)
1676                 return table;
1677
1678         return iptables_init(table_name);
1679 }
1680
1681 struct parse_context {
1682         int argc;
1683         char **argv;
1684         struct ipt_ip *ip;
1685         struct xtables_target *xt_t;
1686         struct xtables_match *xt_m;
1687         struct xtables_rule_match *xt_rm;
1688 };
1689
1690 static int prepare_getopt_args(const char *str, struct parse_context *ctx)
1691 {
1692         char **tokens;
1693         int i;
1694
1695         tokens = g_strsplit_set(str, " ", -1);
1696
1697         i = g_strv_length(tokens);
1698
1699         /* Add space for the argv[0] value */
1700         ctx->argc = i + 1;
1701
1702         /* Don't forget the last NULL entry */
1703         ctx->argv = g_try_malloc0((ctx->argc + 1) * sizeof(char *));
1704         if (ctx->argv == NULL) {
1705                 g_strfreev(tokens);
1706                 return -ENOMEM;
1707         }
1708
1709         /*
1710          * getopt_long() jumps over the first token; we need to add some
1711          * random argv[0] entry.
1712          */
1713         ctx->argv[0] = g_strdup("argh");
1714         for (i = 1; i < ctx->argc; i++)
1715                 ctx->argv[i] = tokens[i - 1];
1716
1717         g_free(tokens);
1718
1719         return 0;
1720 }
1721
1722 #if XTABLES_VERSION_CODE > 5
1723
1724 static int parse_xt_modules(int c, connman_bool_t invert,
1725                                 struct parse_context *ctx)
1726 {
1727         struct xtables_match *m;
1728         struct xtables_rule_match *rm;
1729
1730         DBG("xtables version code > 5");
1731
1732         for (rm = ctx->xt_rm; rm != NULL; rm = rm->next) {
1733                 if (rm->completed != 0)
1734                         continue;
1735
1736                 m = rm->match;
1737
1738                 if (m->x6_parse == NULL && m->parse == NULL)
1739                         continue;
1740
1741                 if (c < (int) m->option_offset ||
1742                                 c >= (int) m->option_offset
1743                                         + XT_OPTION_OFFSET_SCALE)
1744                         continue;
1745
1746                 xtables_option_mpcall(c, ctx->argv, invert, m, NULL);
1747         }
1748
1749         if (ctx->xt_t == NULL)
1750                 return 0;
1751
1752         if (ctx->xt_t->x6_parse == NULL && ctx->xt_t->parse == NULL)
1753                 return 0;
1754
1755         if (c < (int) ctx->xt_t->option_offset ||
1756                         c >= (int) ctx->xt_t->option_offset
1757                                         + XT_OPTION_OFFSET_SCALE)
1758                 return 0;
1759
1760         xtables_option_tpcall(c, ctx->argv, invert, ctx->xt_t, NULL);
1761
1762         return 0;
1763 }
1764
1765 static int final_check_xt_modules(struct parse_context *ctx)
1766 {
1767         struct xtables_rule_match *rm;
1768
1769         DBG("xtables version code > 5");
1770
1771         for (rm = ctx->xt_rm; rm != NULL; rm = rm->next)
1772                 xtables_option_mfcall(rm->match);
1773
1774         if (ctx->xt_t != NULL)
1775                 xtables_option_tfcall(ctx->xt_t);
1776
1777         return 0;
1778 }
1779
1780 #else
1781
1782 static int parse_xt_modules(int c, connman_bool_t invert,
1783                                 struct parse_context *ctx)
1784 {
1785         struct xtables_match *m;
1786         struct xtables_rule_match *rm;
1787         int err;
1788
1789         DBG("xtables version code <= 5");
1790
1791         for (rm = ctx->xt_rm; rm != NULL; rm = rm->next) {
1792                 if (rm->completed == 1)
1793                         continue;
1794
1795                 m = rm->match;
1796
1797                 if (m->parse == NULL)
1798                         continue;
1799
1800                 err = m->parse(c - m->option_offset,
1801                                 argv, invert, &m->mflags,
1802                                 NULL, &m->m);
1803                 if (err > 0)
1804                         return -err;
1805         }
1806
1807         if (ctx->xt_t == NULL)
1808                 return 0;
1809
1810         if (ctx->xt_t->parse == NULL)
1811                 return 0;
1812
1813         err = ctx->xt_m->parse(c - ctx->xt_m->option_offset,
1814                                 ctx->argv, invert, &ctx->xt_m->mflags,
1815                                 NULL, &ctx->xt_m->m);
1816         return -err;
1817 }
1818
1819 static int final_check_xt_modules(struct parse_context *ctx)
1820 {
1821         struct xtables_rule_match *rm;
1822
1823         DBG("xtables version code <= 5");
1824
1825         for (rm = ctx->xt_rm; rm != NULL; rm = rm->next)
1826                 if (rm->match->final_check != NULL)
1827                         rm->match->final_check(rm->match->mflags);
1828
1829         if (ctx->xt_t != NULL && ctx->xt_t->final_check != NULL)
1830                 ctx->xt_t->final_check(ctx->xt_t->tflags);
1831
1832         return 0;
1833 }
1834
1835 #endif
1836
1837 static int parse_rule_spec(struct connman_iptables *table,
1838                                 struct parse_context *ctx)
1839 {
1840         /*
1841          * How the parser works:
1842          *
1843          *  - If getopt finds 's', 'd', 'i', 'o'.
1844          *    just extract the information.
1845          *  - if '!' is found, set the invert flag to true and
1846          *    removes the '!' from the optarg string and jumps
1847          *    back to getopt to reparse the current optarg string.
1848          *    After reparsing the invert flag is reseted to false.
1849          *  - If 'm' or 'j' is found then call either
1850          *    prepare_matches() or prepare_target(). Those function
1851          *    will modify (extend) the longopts for getopt_long.
1852          *    That means getopt will change its matching context according
1853          *    the loaded target.
1854          *
1855          *    Here an example with iptables-test
1856          *
1857          *    argv[0] = ./tools/iptables-test
1858          *    argv[1] = -t
1859          *    argv[2] = filter
1860          *    argv[3] = -A
1861          *    argv[4] = INPUT
1862          *    argv[5] = -m
1863          *    argv[6] = mark
1864          *    argv[7] = --mark
1865          *    argv[8] = 999
1866          *    argv[9] = -j
1867          *    argv[10] = LOG
1868          *
1869          *    getopt found 'm' then the optarg is "mark" and optind 7
1870          *    The longopts array containts before hitting the `case 'm'`
1871          *
1872          *    val A has_arg 1 name append
1873          *    val C has_arg 1 name compare
1874          *    val D has_arg 1 name delete
1875          *    val F has_arg 1 name flush-chain
1876          *    val I has_arg 1 name insert
1877          *    val L has_arg 2 name list
1878          *    val N has_arg 1 name new-chain
1879          *    val P has_arg 1 name policy
1880          *    val X has_arg 1 name delete-chain
1881          *    val d has_arg 1 name destination
1882          *    val i has_arg 1 name in-interface
1883          *    val j has_arg 1 name jump
1884          *    val m has_arg 1 name match
1885          *    val o has_arg 1 name out-interface
1886          *    val s has_arg 1 name source
1887          *    val t has_arg 1 name table
1888          *
1889          *    After executing the `case 'm'` block longopts is
1890          *
1891          *    val A has_arg 1 name append
1892          *    val C has_arg 1 name compare
1893          *    val D has_arg 1 name delete
1894          *    val F has_arg 1 name flush-chain
1895          *    val I has_arg 1 name insert
1896          *    val L has_arg 2 name list
1897          *    val N has_arg 1 name new-chain
1898          *    val P has_arg 1 name policy
1899          *    val X has_arg 1 name delete-chain
1900          *    val d has_arg 1 name destination
1901          *    val i has_arg 1 name in-interface
1902          *    val j has_arg 1 name jump
1903          *    val m has_arg 1 name match
1904          *    val o has_arg 1 name out-interface
1905          *    val s has_arg 1 name source
1906          *    val t has_arg 1 name table
1907          *    val   has_arg 1 name mark
1908          *
1909          *    So the 'mark' matcher has added the 'mark' options
1910          *    and getopt will then return c '256' optarg "999" optind 9
1911          *    And we will hit the 'default' statement which then
1912          *    will call the matchers parser (xt_m->parser() or
1913          *    xtables_option_mpcall() depending on which version
1914          *    of libxtables is found.
1915          */
1916         connman_bool_t invert = FALSE;
1917         int len, c, err;
1918
1919         DBG("");
1920
1921         ctx->ip = g_try_new0(struct ipt_ip, 1);
1922         if (ctx->ip == NULL)
1923                 return -ENOMEM;
1924
1925         /*
1926          * Tell getopt_long not to generate error messages for unknown
1927          * options and also reset optind back to 0.
1928          */
1929         opterr = 0;
1930         optind = 0;
1931
1932         while ((c = getopt_long(ctx->argc, ctx->argv,
1933                                         "-:d:i:o:s:m:j:",
1934                                         iptables_globals.opts, NULL)) != -1) {
1935                 switch (c) {
1936                 case 's':
1937                         /* Source specification */
1938                         if (!parse_ip_and_mask(optarg,
1939                                                 &ctx->ip->src,
1940                                                 &ctx->ip->smsk))
1941                                 break;
1942
1943                         if (invert)
1944                                 ctx->ip->invflags |= IPT_INV_SRCIP;
1945
1946                         break;
1947                 case 'd':
1948                         /* Destination specification */
1949                         if (!parse_ip_and_mask(optarg,
1950                                                 &ctx->ip->dst,
1951                                                 &ctx->ip->dmsk))
1952                                 break;
1953
1954                         if (invert)
1955                                 ctx->ip->invflags |= IPT_INV_DSTIP;
1956                         break;
1957                 case 'i':
1958                         /* In interface specification */
1959                         len = strlen(optarg);
1960
1961                         if (len + 1 > IFNAMSIZ)
1962                                 break;
1963
1964                         strcpy(ctx->ip->iniface, optarg);
1965                         memset(ctx->ip->iniface_mask, 0xff, len + 1);
1966
1967                         if (invert)
1968                                 ctx->ip->invflags |= IPT_INV_VIA_IN;
1969
1970                         break;
1971                 case 'o':
1972                         /* Out interface specification */
1973                         len = strlen(optarg);
1974
1975                         if (len + 1 > IFNAMSIZ)
1976                                 break;
1977
1978                         strcpy(ctx->ip->outiface, optarg);
1979                         memset(ctx->ip->outiface_mask, 0xff, len + 1);
1980
1981                         if (invert)
1982                                 ctx->ip->invflags |= IPT_INV_VIA_OUT;
1983
1984                         break;
1985                 case 'm':
1986                         /* Matches */
1987                         ctx->xt_m = prepare_matches(table, &ctx->xt_rm, optarg);
1988                         if (ctx->xt_m == NULL) {
1989                                 err = -EINVAL;
1990                                 goto out;
1991                         }
1992
1993                         break;
1994                 case 'j':
1995                         /* Target */
1996                         ctx->xt_t = prepare_target(table, optarg);
1997                         if (ctx->xt_t == NULL) {
1998                                 err = -EINVAL;
1999                                 goto out;
2000                         }
2001
2002                         break;
2003                 case 1:
2004                         if (optarg[0] == '!' && optarg[1] == '\0') {
2005                                 invert = TRUE;
2006
2007                                 /* Remove the '!' from the optarg */
2008                                 optarg[0] = '\0';
2009
2010                                 /*
2011                                  * And recall getopt_long without reseting
2012                                  * invert.
2013                                  */
2014                                 continue;
2015                         }
2016
2017                         break;
2018                 default:
2019                         err = parse_xt_modules(c, invert, ctx);
2020                         if (err == 1)
2021                                 continue;
2022
2023                         break;
2024                 }
2025
2026                 invert = FALSE;
2027         }
2028
2029         err = final_check_xt_modules(ctx);
2030
2031 out:
2032         return err;
2033 }
2034
2035 static void reset_xtables(void)
2036 {
2037         struct xtables_match *xt_m;
2038         struct xtables_target *xt_t;
2039
2040         /*
2041          * As side effect parsing a rule sets some global flags
2042          * which will be evaluated/verified. Let's reset them
2043          * to ensure we can parse more than one rule.
2044          *
2045          * Clear all flags because the flags are only valid
2046          * for one rule.
2047          */
2048         for (xt_m = xtables_matches; xt_m != NULL; xt_m = xt_m->next)
2049                 xt_m->mflags = 0;
2050
2051         for (xt_t = xtables_targets; xt_t != NULL; xt_t = xt_t->next) {
2052                 xt_t->tflags = 0;
2053                 xt_t->used = 0;
2054         }
2055
2056         /*
2057          * We need also to free the memory implicitly allocated
2058          * during parsing (see xtables_options_xfrm()).
2059          * Note xt_params is actually iptables_globals.
2060          */
2061         if (xt_params->opts != xt_params->orig_opts) {
2062                 g_free(xt_params->opts);
2063                 xt_params->opts = xt_params->orig_opts;
2064         }
2065         xt_params->option_offset = 0;
2066 }
2067
2068 static void cleanup_parse_context(struct parse_context *ctx)
2069 {
2070         struct xtables_rule_match *rm, *tmp;
2071
2072         g_strfreev(ctx->argv);
2073         g_free(ctx->ip);
2074         if (ctx->xt_t != NULL) {
2075                 g_free(ctx->xt_t->t);
2076                 ctx->xt_t->t = NULL;
2077         }
2078         if (ctx->xt_m != NULL) {
2079                 g_free(ctx->xt_m->m);
2080                 ctx->xt_m->m = NULL;
2081         }
2082         for (tmp = NULL, rm = ctx->xt_rm; rm != NULL; rm = rm->next) {
2083                 if (tmp != NULL)
2084                         g_free(tmp);
2085                 tmp = rm;
2086         }
2087         g_free(tmp);
2088
2089         g_free(ctx);
2090 }
2091
2092 int __connman_iptables_new_chain(const char *table_name,
2093                                         const char *chain)
2094 {
2095         struct connman_iptables *table;
2096
2097         DBG("-t %s -N %s", table_name, chain);
2098
2099         table = pre_load_table(table_name, NULL);
2100         if (table == NULL)
2101                 return -EINVAL;
2102
2103         return iptables_add_chain(table, chain);
2104 }
2105
2106 int __connman_iptables_delete_chain(const char *table_name,
2107                                         const char *chain)
2108 {
2109         struct connman_iptables *table;
2110
2111         DBG("-t %s -X %s", table_name, chain);
2112
2113         table = pre_load_table(table_name, NULL);
2114         if (table == NULL)
2115                 return -EINVAL;
2116
2117         return iptables_delete_chain(table, chain);
2118 }
2119
2120 int __connman_iptables_flush_chain(const char *table_name,
2121                                         const char *chain)
2122 {
2123         struct connman_iptables *table;
2124
2125         DBG("-t %s -F %s", table_name, chain);
2126
2127         table = pre_load_table(table_name, NULL);
2128         if (table == NULL)
2129                 return -EINVAL;
2130
2131         return iptables_flush_chain(table, chain);
2132 }
2133
2134 int __connman_iptables_change_policy(const char *table_name,
2135                                         const char *chain,
2136                                         const char *policy)
2137 {
2138         struct connman_iptables *table;
2139
2140         DBG("-t %s -F %s", table_name, chain);
2141
2142         table = pre_load_table(table_name, NULL);
2143         if (table == NULL)
2144                 return -EINVAL;
2145
2146         return iptables_change_policy(table, chain, policy);
2147 }
2148
2149 int __connman_iptables_append(const char *table_name,
2150                                 const char *chain,
2151                                 const char *rule_spec)
2152 {
2153         struct connman_iptables *table;
2154         struct parse_context *ctx;
2155         const char *target_name;
2156         int err;
2157
2158         ctx = g_try_new0(struct parse_context, 1);
2159         if (ctx == NULL)
2160                 return -ENOMEM;
2161
2162         DBG("-t %s -A %s %s", table_name, chain, rule_spec);
2163
2164         err = prepare_getopt_args(rule_spec, ctx);
2165         if (err < 0)
2166                 goto out;
2167
2168         table = pre_load_table(table_name, NULL);
2169         if (table == NULL) {
2170                 err = -EINVAL;
2171                 goto out;
2172         }
2173
2174         err = parse_rule_spec(table, ctx);
2175         if (err < 0)
2176                 goto out;
2177
2178         if (ctx->xt_t == NULL)
2179                 target_name = NULL;
2180         else
2181                 target_name = ctx->xt_t->name;
2182
2183         err = iptables_insert_rule(table, ctx->ip, chain,
2184                                 target_name, ctx->xt_t, ctx->xt_rm);
2185 out:
2186         cleanup_parse_context(ctx);
2187         reset_xtables();
2188
2189         return err;
2190 }
2191
2192 int __connman_iptables_delete(const char *table_name,
2193                                 const char *chain,
2194                                 const char *rule_spec)
2195 {
2196         struct connman_iptables *table;
2197         struct parse_context *ctx;
2198         const char *target_name;
2199         int err;
2200
2201         ctx = g_try_new0(struct parse_context, 1);
2202         if (ctx == NULL)
2203                 return -ENOMEM;
2204
2205         DBG("-t %s -D %s %s", table_name, chain, rule_spec);
2206
2207         err = prepare_getopt_args(rule_spec, ctx);
2208         if (err < 0)
2209                 goto out;
2210
2211         table = pre_load_table(table_name, NULL);
2212         if (table == NULL) {
2213                 err = -EINVAL;
2214                 goto out;
2215         }
2216
2217         err = parse_rule_spec(table, ctx);
2218         if (err < 0)
2219                 goto out;
2220
2221         if (ctx->xt_t == NULL)
2222                 target_name = NULL;
2223         else
2224                 target_name = ctx->xt_t->name;
2225
2226         err = iptables_delete_rule(table, ctx->ip, chain,
2227                                 target_name, ctx->xt_t, ctx->xt_m,
2228                                 ctx->xt_rm);
2229 out:
2230         cleanup_parse_context(ctx);
2231         reset_xtables();
2232
2233         return err;
2234 }
2235
2236 int __connman_iptables_commit(const char *table_name)
2237 {
2238         struct connman_iptables *table;
2239         struct ipt_replace *repl;
2240         int err;
2241
2242         DBG("%s", table_name);
2243
2244         table = g_hash_table_lookup(table_hash, table_name);
2245         if (table == NULL)
2246                 return -EINVAL;
2247
2248         repl = iptables_blob(table);
2249
2250         if (debug_enabled == TRUE)
2251                 dump_ipt_replace(repl);
2252
2253         err = iptables_replace(table, repl);
2254
2255         g_free(repl->counters);
2256         g_free(repl);
2257
2258         if (err < 0)
2259             return err;
2260
2261         g_hash_table_remove(table_hash, table_name);
2262
2263         return 0;
2264 }
2265
2266 static void remove_table(gpointer user_data)
2267 {
2268         struct connman_iptables *table = user_data;
2269
2270         table_cleanup(table);
2271 }
2272
2273 static int flush_table_cb(struct ipt_entry *entry, int builtin,
2274                                 unsigned int hook, size_t size,
2275                                 unsigned int offset, void *user_data)
2276 {
2277         GSList **chains = user_data;
2278         struct xt_entry_target *target;
2279         char *name;
2280
2281         if (offset + entry->next_offset == size)
2282                 return 0;
2283
2284         target = ipt_get_target(entry);
2285
2286         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET))
2287                 name = g_strdup((const char*)target->data);
2288         else if (builtin >= 0)
2289                   name = g_strdup(hooknames[builtin]);
2290         else
2291                 return 0;
2292
2293         *chains = g_slist_prepend(*chains, name);
2294
2295         return 0;
2296 }
2297
2298 void flush_table(const char *name)
2299 {
2300         GSList *chains = NULL, *list;
2301         struct connman_iptables *table;
2302
2303         table = pre_load_table(name, NULL);
2304         if (table == NULL)
2305                 return;
2306
2307         iterate_entries(table->blob_entries->entrytable,
2308                         table->info->valid_hooks,
2309                         table->info->hook_entry,
2310                         table->info->underflow,
2311                         table->blob_entries->size,
2312                         flush_table_cb, &chains);
2313
2314
2315         /*
2316          * The offset update code is fragile and it works
2317          * only safe if we remove elements and move forwards
2318          * in the table.
2319          */
2320         chains = g_slist_reverse(chains);
2321
2322         for (list = chains; list != NULL; list = list->next) {
2323                 char *chain = list->data;
2324
2325                 DBG("chain %s", chain);
2326                 iptables_flush_chain(table, chain);
2327         }
2328
2329         __connman_iptables_commit(name);
2330         g_slist_free_full(chains, g_free);
2331 }
2332
2333 int __connman_iptables_init(void)
2334 {
2335         DBG("");
2336
2337         if (getenv("CONNMAN_IPTABLES_DEBUG"))
2338                 debug_enabled = TRUE;
2339
2340         table_hash = g_hash_table_new_full(g_str_hash, g_str_equal,
2341                                                 g_free, remove_table);
2342
2343         xtables_init_all(&iptables_globals, NFPROTO_IPV4);
2344
2345         return 0;
2346 }
2347
2348 void __connman_iptables_cleanup(void)
2349 {
2350         DBG("");
2351
2352         g_hash_table_destroy(table_hash);
2353 }