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