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
 179 typedef int (*iterate_entries_cb_t)(struct connman_iptables *table,
 180                                         struct ipt_entry *entry, int builtin,
 181                                         unsigned int hook, unsigned int offset,
 182                                         void *user_data);
 183
 184 static int iterate_entries(struct connman_iptables *table,
 185                                 struct ipt_entry *entries,
 186                                 unsigned int valid_hooks,
 187                                 unsigned int *hook_entry,
 188                                 size_t size, iterate_entries_cb_t cb,
 189                                 void *user_data)
 190 {
 191         unsigned int i, h;
 192         int builtin, err;
 193         struct ipt_entry *entry;
 194
 195         if (valid_hooks != 0)
 196                 h = __builtin_ffs(valid_hooks) - 1;
 197         else
 198                 h = NF_INET_NUMHOOKS;
 199
 200         for (i = 0, entry = entries; i < size;
 201                         i += entry->next_offset) {
 202                 builtin = -1;
 203                 entry = (void *)entries + i;
 204
 205                 /*
 206                  * Find next valid hook which offset is higher
 207                  * or equal with the current offset.
 208                  */
 209                 if (h < NF_INET_NUMHOOKS) {
 210                         if (hook_entry[h] < i) {
 211                                 valid_hooks ^= (1 << h);
 212
 213                                 if (valid_hooks != 0)
 214                                         h = __builtin_ffs(valid_hooks) - 1;
 215                                 else
 216                                         h = NF_INET_NUMHOOKS;
 217                         }
 218
 219                         if (hook_entry[h] == i)
 220                                 builtin = h;
 221                 }
 222
 223                 err = cb(table, entry, builtin, h, i, user_data);
 224                 if (err < 0)
 225                         return err;
 226
 227         }
 228
 229         return 0;
 230 }
 231
 232 static unsigned long entry_to_offset(struct connman_iptables *table,
 233                                         struct ipt_entry *entry)
 234 {
 235         return (void *)entry - (void *)table->blob_entries->entrytable;
 236 }
 237
 238 static int target_to_verdict(const char *target_name)
 239 {
 240         if (!strcmp(target_name, LABEL_ACCEPT))
 241                 return -NF_ACCEPT - 1;
 242
 243         if (!strcmp(target_name, LABEL_DROP))
 244                 return -NF_DROP - 1;
 245
 246         if (!strcmp(target_name, LABEL_QUEUE))
 247                 return -NF_QUEUE - 1;
 248
 249         if (!strcmp(target_name, LABEL_RETURN))
 250                 return XT_RETURN;
 251
 252         return 0;
 253 }
 254
 255 static gboolean is_builtin_target(const char *target_name)
 256 {
 257         if (!strcmp(target_name, LABEL_ACCEPT) ||
 258                 !strcmp(target_name, LABEL_DROP) ||
 259                 !strcmp(target_name, LABEL_QUEUE) ||
 260                 !strcmp(target_name, LABEL_RETURN))
 261                 return TRUE;
 262
 263         return FALSE;
 264 }
 265
 266 static gboolean is_jump(struct connman_iptables_entry *e)
 267 {
 268         struct xt_entry_target *target;
 269
 270         target = ipt_get_target(e->entry);
 271
 272         if (!strcmp(target->u.user.name, IPT_STANDARD_TARGET)) {
 273                 struct xt_standard_target *t;
 274
 275                 t = (struct xt_standard_target *)target;
 276
 277                 switch (t->verdict) {
 278                 case XT_RETURN:
 279                 case -NF_ACCEPT - 1:
 280                 case -NF_DROP - 1:
 281                 case -NF_QUEUE - 1:
 282                 case -NF_STOP - 1:
 283                         return false;
 284
 285                 default:
 286                         return true;
 287                 }
 288         }
 289
 290         return false;
 291 }
 292
 293 static gboolean is_chain(struct connman_iptables *table,
 294                                 struct connman_iptables_entry *e)
 295 {
 296         struct ipt_entry *entry;
 297         struct xt_entry_target *target;
 298
 299         entry = e->entry;
 300         if (e->builtin >= 0)
 301                 return TRUE;
 302
 303         target = ipt_get_target(entry);
 304         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET))
 305                 return TRUE;
 306
 307         return FALSE;
 308 }
 309
 310 static GList *find_chain_head(struct connman_iptables *table,
 311                                 const char *chain_name)
 312 {
 313         GList *list;
 314         struct connman_iptables_entry *head;
 315         struct ipt_entry *entry;
 316         struct xt_entry_target *target;
 317         int builtin;
 318
 319         for (list = table->entries; list; list = list->next) {
 320                 head = list->data;
 321                 entry = head->entry;
 322
 323                 /* Buit-in chain */
 324                 builtin = head->builtin;
 325                 if (builtin >= 0 && !strcmp(hooknames[builtin], chain_name))
 326                         break;
 327
 328                 /* User defined chain */
 329                 target = ipt_get_target(entry);
 330                 if (!strcmp(target->u.user.name, IPT_ERROR_TARGET) &&
 331                     !strcmp((char *)target->data, chain_name))
 332                         break;
 333         }
 334
 335         return list;
 336 }
 337
 338 static GList *find_chain_tail(struct connman_iptables *table,
 339                                 const char *chain_name)
 340 {
 341         struct connman_iptables_entry *tail;
 342         GList *chain_head, *list;
 343
 344         chain_head = find_chain_head(table, chain_name);
 345         if (chain_head == NULL)
 346                 return NULL;
 347
 348         /* Then we look for the next chain */
 349         for (list = chain_head->next; list; list = list->next) {
 350                 tail = list->data;
 351
 352                 if (is_chain(table, tail))
 353                         return list;
 354         }
 355
 356         /* Nothing found, we return the table end */
 357         return g_list_last(table->entries);
 358 }
 359
 360
 361 static void update_offsets(struct connman_iptables *table)
 362 {
 363         GList *list, *prev;
 364         struct connman_iptables_entry *entry, *prev_entry;
 365
 366         for (list = table->entries; list; list = list->next) {
 367                 entry = list->data;
 368
 369                 if (list == table->entries) {
 370                         entry->offset = 0;
 371
 372                         continue;
 373                 }
 374
 375                 prev = list->prev;
 376                 prev_entry = prev->data;
 377
 378                 entry->offset = prev_entry->offset +
 379                                         prev_entry->entry->next_offset;
 380         }
 381 }
 382
 383 static void update_targets_reference(struct connman_iptables *table,
 384                                 struct connman_iptables_entry *entry_before,
 385                                 struct connman_iptables_entry *modified_entry,
 386                                 gboolean is_removing)
 387 {
 388         struct connman_iptables_entry *tmp;
 389         struct xt_standard_target *t;
 390         GList *list;
 391         int offset;
 392
 393         offset = modified_entry->entry->next_offset;
 394
 395         for (list = table->entries; list; list = list->next) {
 396                 tmp = list->data;
 397
 398                 if (!is_jump(tmp))
 399                         continue;
 400
 401                 t = (struct xt_standard_target *)ipt_get_target(tmp->entry);
 402
 403                 if (is_removing == TRUE) {
 404                         if (t->verdict >= entry_before->offset)
 405                                 t->verdict -= offset;
 406                 } else {
 407                         if (t->verdict > entry_before->offset)
 408                                 t->verdict += offset;
 409                 }
 410         }
 411 }
 412
 413 static int iptables_add_entry(struct connman_iptables *table,
 414                                 struct ipt_entry *entry, GList *before,
 415                                         int builtin)
 416 {
 417         struct connman_iptables_entry *e, *entry_before;
 418
 419         if (table == NULL)
 420                 return -1;
 421
 422         e = g_try_malloc0(sizeof(struct connman_iptables_entry));
 423         if (e == NULL)
 424                 return -1;
 425
 426         e->entry = entry;
 427         e->builtin = builtin;
 428
 429         table->entries = g_list_insert_before(table->entries, before, e);
 430         table->num_entries++;
 431         table->size += entry->next_offset;
 432
 433         if (before == NULL) {
 434                 e->offset = table->size - entry->next_offset;
 435
 436                 return 0;
 437         }
 438
 439         entry_before = before->data;
 440
 441         /*
 442          * We've just appended/insterted a new entry. All references
 443          * should be bumped accordingly.
 444          */
 445         update_targets_reference(table, entry_before, e, FALSE);
 446
 447         update_offsets(table);
 448
 449         return 0;
 450 }
 451
 452 static int remove_table_entry(struct connman_iptables *table,
 453                                 struct connman_iptables_entry *entry)
 454 {
 455         int removed = 0;
 456
 457         table->num_entries--;
 458         table->size -= entry->entry->next_offset;
 459         removed = entry->entry->next_offset;
 460
 461         g_free(entry->entry);
 462
 463         table->entries = g_list_remove(table->entries, entry);
 464
 465         return removed;
 466 }
 467
 468 static int iptables_flush_chain(struct connman_iptables *table,
 469                                                 const char *name)
 470 {
 471         GList *chain_head, *chain_tail, *list, *next;
 472         struct connman_iptables_entry *entry;
 473         int builtin, removed = 0;
 474
 475         chain_head = find_chain_head(table, name);
 476         if (chain_head == NULL)
 477                 return -EINVAL;
 478
 479         chain_tail = find_chain_tail(table, name);
 480         if (chain_tail == NULL)
 481                 return -EINVAL;
 482
 483         entry = chain_head->data;
 484         builtin = entry->builtin;
 485
 486         if (builtin >= 0)
 487                 list = chain_head;
 488         else
 489                 list = chain_head->next;
 490
 491         if (list == chain_tail->prev)
 492                 return 0;
 493
 494         while (list != chain_tail->prev) {
 495                 entry = list->data;
 496                 next = g_list_next(list);
 497
 498                 removed += remove_table_entry(table, entry);
 499
 500                 list = next;
 501         }
 502
 503         if (builtin >= 0) {
 504                 struct connman_iptables_entry *e;
 505
 506                 entry = list->data;
 507
 508                 entry->builtin = builtin;
 509
 510                 table->underflow[builtin] -= removed;
 511
 512                 for (list = chain_tail; list; list = list->next) {
 513                         e = list->data;
 514
 515                         builtin = e->builtin;
 516                         if (builtin < 0)
 517                                 continue;
 518
 519                         table->hook_entry[builtin] -= removed;
 520                         table->underflow[builtin] -= removed;
 521                 }
 522         }
 523
 524         update_offsets(table);
 525
 526         return 0;
 527 }
 528
 529 static int iptables_add_chain(struct connman_iptables *table,
 530                                 const char *name)
 531 {
 532         GList *last;
 533         struct ipt_entry *entry_head;
 534         struct ipt_entry *entry_return;
 535         struct error_target *error;
 536         struct ipt_standard_target *standard;
 537         u_int16_t entry_head_size, entry_return_size;
 538
 539         last = g_list_last(table->entries);
 540
 541         /*
 542          * An empty chain is composed of:
 543          * - A head entry, with no match and an error target.
 544          *   The error target data is the chain name.
 545          * - A tail entry, with no match and a standard target.
 546          *   The standard target verdict is XT_RETURN (return to the
 547          *   caller).
 548          */
 549
 550         /* head entry */
 551         entry_head_size = sizeof(struct ipt_entry) +
 552                                 sizeof(struct error_target);
 553         entry_head = g_try_malloc0(entry_head_size);
 554         if (entry_head == NULL)
 555                 goto err_head;
 556
 557         memset(entry_head, 0, entry_head_size);
 558
 559         entry_head->target_offset = sizeof(struct ipt_entry);
 560         entry_head->next_offset = entry_head_size;
 561
 562         error = (struct error_target *) entry_head->elems;
 563         strcpy(error->t.u.user.name, IPT_ERROR_TARGET);
 564         error->t.u.user.target_size = ALIGN(sizeof(struct error_target));
 565         strcpy(error->error, name);
 566
 567         if (iptables_add_entry(table, entry_head, last, -1) < 0)
 568                 goto err_head;
 569
 570         /* tail entry */
 571         entry_return_size = sizeof(struct ipt_entry) +
 572                                 sizeof(struct ipt_standard_target);
 573         entry_return = g_try_malloc0(entry_return_size);
 574         if (entry_return == NULL)
 575                 goto err;
 576
 577         memset(entry_return, 0, entry_return_size);
 578
 579         entry_return->target_offset = sizeof(struct ipt_entry);
 580         entry_return->next_offset = entry_return_size;
 581
 582         standard = (struct ipt_standard_target *) entry_return->elems;
 583         standard->target.u.user.target_size =
 584                                 ALIGN(sizeof(struct ipt_standard_target));
 585         standard->verdict = XT_RETURN;
 586
 587         if (iptables_add_entry(table, entry_return, last, -1) < 0)
 588                 goto err;
 589
 590         return 0;
 591
 592 err:
 593         g_free(entry_return);
 594 err_head:
 595         g_free(entry_head);
 596
 597         return -ENOMEM;
 598 }
 599
 600 static int iptables_delete_chain(struct connman_iptables *table,
 601                                         const char *name)
 602 {
 603         struct connman_iptables_entry *entry;
 604         GList *chain_head, *chain_tail;
 605
 606         chain_head = find_chain_head(table, name);
 607         if (chain_head == NULL)
 608                 return -EINVAL;
 609
 610         entry = chain_head->data;
 611
 612         /* We cannot remove builtin chain */
 613         if (entry->builtin >= 0)
 614                 return -EINVAL;
 615
 616         chain_tail = find_chain_tail(table, name);
 617         if (chain_tail == NULL)
 618                 return -EINVAL;
 619
 620         /* Chain must be flushed */
 621         if (chain_head->next != chain_tail->prev)
 622                 return -EINVAL;
 623
 624         remove_table_entry(table, entry);
 625
 626         entry = chain_tail->prev->data;
 627         remove_table_entry(table, entry);
 628
 629         update_offsets(table);
 630
 631         return 0;
 632 }
 633
 634 static struct ipt_entry *new_rule(struct ipt_ip *ip,
 635                 const char *target_name, struct xtables_target *xt_t,
 636                 struct xtables_rule_match *xt_rm)
 637 {
 638         struct xtables_rule_match *tmp_xt_rm;
 639         struct ipt_entry *new_entry;
 640         size_t match_size, target_size;
 641
 642         match_size = 0;
 643         for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL; tmp_xt_rm = tmp_xt_rm->next)
 644                 match_size += tmp_xt_rm->match->m->u.match_size;
 645
 646         if (xt_t)
 647                 target_size = ALIGN(xt_t->t->u.target_size);
 648         else
 649                 target_size = ALIGN(sizeof(struct xt_standard_target));
 650
 651         new_entry = g_try_malloc0(sizeof(struct ipt_entry) + target_size +
 652                                                                 match_size);
 653         if (new_entry == NULL)
 654                 return NULL;
 655
 656         memcpy(&new_entry->ip, ip, sizeof(struct ipt_ip));
 657
 658         new_entry->target_offset = sizeof(struct ipt_entry) + match_size;
 659         new_entry->next_offset = sizeof(struct ipt_entry) + target_size +
 660                                                                 match_size;
 661
 662         match_size = 0;
 663         for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL;
 664                                 tmp_xt_rm = tmp_xt_rm->next) {
 665                 memcpy(new_entry->elems + match_size, tmp_xt_rm->match->m,
 666                                         tmp_xt_rm->match->m->u.match_size);
 667                 match_size += tmp_xt_rm->match->m->u.match_size;
 668         }
 669
 670         if (xt_t) {
 671                 struct xt_entry_target *entry_target;
 672
 673                 entry_target = ipt_get_target(new_entry);
 674                 memcpy(entry_target, xt_t->t, target_size);
 675         }
 676
 677         return new_entry;
 678 }
 679
 680 static void update_hooks(struct connman_iptables *table, GList *chain_head,
 681                                 struct ipt_entry *entry)
 682 {
 683         GList *list;
 684         struct connman_iptables_entry *head, *e;
 685         int builtin;
 686
 687         if (chain_head == NULL)
 688                 return;
 689
 690         head = chain_head->data;
 691
 692         builtin = head->builtin;
 693         if (builtin < 0)
 694                 return;
 695
 696         table->underflow[builtin] += entry->next_offset;
 697
 698         for (list = chain_head->next; list; list = list->next) {
 699                 e = list->data;
 700
 701                 builtin = e->builtin;
 702                 if (builtin < 0)
 703                         continue;
 704
 705                 table->hook_entry[builtin] += entry->next_offset;
 706                 table->underflow[builtin] += entry->next_offset;
 707         }
 708 }
 709
 710 static struct ipt_entry *prepare_rule_inclusion(struct connman_iptables *table,
 711                                 struct ipt_ip *ip, const char *chain_name,
 712                                 const char *target_name,
 713                                 struct xtables_target *xt_t,
 714                                 int *builtin, struct xtables_rule_match *xt_rm)
 715 {
 716         GList *chain_tail, *chain_head;
 717         struct ipt_entry *new_entry;
 718         struct connman_iptables_entry *head;
 719
 720         chain_head = find_chain_head(table, chain_name);
 721         if (chain_head == NULL)
 722                 return NULL;
 723
 724         chain_tail = find_chain_tail(table, chain_name);
 725         if (chain_tail == NULL)
 726                 return NULL;
 727
 728         new_entry = new_rule(ip, target_name, xt_t, xt_rm);
 729         if (new_entry == NULL)
 730                 return NULL;
 731
 732         update_hooks(table, chain_head, new_entry);
 733
 734         /*
 735          * If the chain is builtin, and does not have any rule,
 736          * then the one that we're inserting is becoming the head
 737          * and thus needs the builtin flag.
 738          */
 739         head = chain_head->data;
 740         if (head->builtin < 0)
 741                 *builtin = -1;
 742         else if (chain_head == chain_tail->prev) {
 743                 *builtin = head->builtin;
 744                 head->builtin = -1;
 745         }
 746
 747         return new_entry;
 748 }
 749
 750 static int iptables_append_rule(struct connman_iptables *table,
 751                                 struct ipt_ip *ip, char *chain_name,
 752                                 char *target_name, struct xtables_target *xt_t,
 753                                 struct xtables_rule_match *xt_rm)
 754 {
 755         GList *chain_tail;
 756         struct ipt_entry *new_entry;
 757         int builtin = -1, ret;
 758
 759         DBG("");
 760
 761         chain_tail = find_chain_tail(table, chain_name);
 762         if (chain_tail == NULL)
 763                 return -EINVAL;
 764
 765         new_entry = prepare_rule_inclusion(table, ip, chain_name,
 766                                         target_name, xt_t, &builtin, xt_rm);
 767         if (new_entry == NULL)
 768                 return -EINVAL;
 769
 770         ret = iptables_add_entry(table, new_entry, chain_tail->prev, builtin);
 771         if (ret < 0)
 772                 g_free(new_entry);
 773
 774         return ret;
 775 }
 776
 777 static int iptables_insert_rule(struct connman_iptables *table,
 778                                 struct ipt_ip *ip, const char *chain_name,
 779                                 const char *target_name,
 780                                 struct xtables_target *xt_t,
 781                                 struct xtables_rule_match *xt_rm)
 782 {
 783         struct ipt_entry *new_entry;
 784         int builtin = -1, ret;
 785         GList *chain_head;
 786
 787         chain_head = find_chain_head(table, chain_name);
 788         if (chain_head == NULL)
 789                 return -EINVAL;
 790
 791         new_entry = prepare_rule_inclusion(table, ip, chain_name,
 792                                         target_name, xt_t, &builtin, xt_rm);
 793         if (new_entry == NULL)
 794                 return -EINVAL;
 795
 796         if (builtin == -1)
 797                 chain_head = chain_head->next;
 798
 799         ret = iptables_add_entry(table, new_entry, chain_head, builtin);
 800         if (ret < 0)
 801                 g_free(new_entry);
 802
 803         return ret;
 804 }
 805
 806 static gboolean is_same_ipt_entry(struct ipt_entry *i_e1,
 807                                         struct ipt_entry *i_e2)
 808 {
 809         if (memcmp(&i_e1->ip, &i_e2->ip, sizeof(struct ipt_ip)) != 0)
 810                 return FALSE;
 811
 812         if (i_e1->target_offset != i_e2->target_offset)
 813                 return FALSE;
 814
 815         if (i_e1->next_offset != i_e2->next_offset)
 816                 return FALSE;
 817
 818         return TRUE;
 819 }
 820
 821 static gboolean is_same_target(struct xt_entry_target *xt_e_t1,
 822                                         struct xt_entry_target *xt_e_t2)
 823 {
 824         if (xt_e_t1 == NULL || xt_e_t2 == NULL)
 825                 return FALSE;
 826
 827         if (strcmp(xt_e_t1->u.user.name, IPT_STANDARD_TARGET) == 0) {
 828                 struct xt_standard_target *xt_s_t1;
 829                 struct xt_standard_target *xt_s_t2;
 830
 831                 xt_s_t1 = (struct xt_standard_target *) xt_e_t1;
 832                 xt_s_t2 = (struct xt_standard_target *) xt_e_t2;
 833
 834                 if (xt_s_t1->verdict != xt_s_t2->verdict)
 835                         return FALSE;
 836         } else {
 837                 if (xt_e_t1->u.target_size != xt_e_t2->u.target_size)
 838                         return FALSE;
 839
 840                 if (strcmp(xt_e_t1->u.user.name, xt_e_t2->u.user.name) != 0)
 841                         return FALSE;
 842         }
 843
 844         return TRUE;
 845 }
 846
 847 static gboolean is_same_match(struct xt_entry_match *xt_e_m1,
 848                                 struct xt_entry_match *xt_e_m2)
 849 {
 850         if (xt_e_m1 == NULL || xt_e_m2 == NULL)
 851                 return FALSE;
 852
 853         if (xt_e_m1->u.match_size != xt_e_m2->u.match_size)
 854                 return FALSE;
 855
 856         if (xt_e_m1->u.user.revision != xt_e_m2->u.user.revision)
 857                 return FALSE;
 858
 859         if (strcmp(xt_e_m1->u.user.name, xt_e_m2->u.user.name) != 0)
 860                 return FALSE;
 861
 862         return TRUE;
 863 }
 864
 865 static GList *find_existing_rule(struct connman_iptables *table,
 866                                 struct ipt_ip *ip, const char *chain_name,
 867                                 const char *target_name,
 868                                 struct xtables_target *xt_t,
 869                                 struct xtables_match *xt_m,
 870                                 struct xtables_rule_match *xt_rm)
 871 {
 872         GList *chain_tail, *chain_head, *list;
 873         struct xt_entry_target *xt_e_t = NULL;
 874         struct xt_entry_match *xt_e_m = NULL;
 875         struct connman_iptables_entry *entry;
 876         struct ipt_entry *entry_test;
 877         int builtin;
 878
 879         chain_head = find_chain_head(table, chain_name);
 880         if (chain_head == NULL)
 881                 return NULL;
 882
 883         chain_tail = find_chain_tail(table, chain_name);
 884         if (chain_tail == NULL)
 885                 return NULL;
 886
 887         if (!xt_t && !xt_m)
 888                 return NULL;
 889
 890         entry_test = new_rule(ip, target_name, xt_t, xt_rm);
 891         if (entry_test == NULL)
 892                 return NULL;
 893
 894         if (xt_t != NULL)
 895                 xt_e_t = ipt_get_target(entry_test);
 896         if (xt_m != NULL)
 897                 xt_e_m = (struct xt_entry_match *)entry_test->elems;
 898
 899         entry = chain_head->data;
 900         builtin = entry->builtin;
 901
 902         if (builtin >= 0)
 903                 list = chain_head;
 904         else
 905                 list = chain_head->next;
 906
 907         for (; list != chain_tail->prev; list = list->next) {
 908                 struct connman_iptables_entry *tmp;
 909                 struct ipt_entry *tmp_e;
 910
 911                 tmp = list->data;
 912                 tmp_e = tmp->entry;
 913
 914                 if (is_same_ipt_entry(entry_test, tmp_e) == FALSE)
 915                         continue;
 916
 917                 if (xt_t != NULL) {
 918                         struct xt_entry_target *tmp_xt_e_t;
 919
 920                         tmp_xt_e_t = ipt_get_target(tmp_e);
 921
 922                         if (!is_same_target(tmp_xt_e_t, xt_e_t))
 923                                 continue;
 924                 }
 925
 926                 if (xt_m != NULL) {
 927                         struct xt_entry_match *tmp_xt_e_m;
 928
 929                         tmp_xt_e_m = (struct xt_entry_match *)tmp_e->elems;
 930
 931                         if (!is_same_match(tmp_xt_e_m, xt_e_m))
 932                                 continue;
 933                 }
 934
 935                 break;
 936         }
 937
 938         g_free(entry_test);
 939
 940         if (list != chain_tail->prev)
 941                 return list;
 942
 943         return NULL;
 944 }
 945
 946 static int iptables_delete_rule(struct connman_iptables *table,
 947                                 struct ipt_ip *ip, const char *chain_name,
 948                                 const char *target_name,
 949                                 struct xtables_target *xt_t,
 950                                 struct xtables_match *xt_m,
 951                                 struct xtables_rule_match *xt_rm)
 952 {
 953         struct connman_iptables_entry *entry;
 954         GList *chain_tail, *list;
 955         int builtin, removed;
 956
 957         removed = 0;
 958
 959         chain_tail = find_chain_tail(table, chain_name);
 960         if (chain_tail == NULL)
 961                 return -EINVAL;
 962
 963         list = find_existing_rule(table, ip, chain_name, target_name,
 964                                                         xt_t, xt_m, xt_rm);
 965         if (list == NULL)
 966                 return -EINVAL;
 967
 968         entry = list->data;
 969         if (entry == NULL)
 970                 return -EINVAL;
 971
 972         builtin = entry->builtin;
 973
 974         /* We have deleted a rule,
 975          * all references should be bumped accordingly */
 976         if (list->next != NULL)
 977                 update_targets_reference(table, list->next->data,
 978                                                 list->data, TRUE);
 979
 980         removed += remove_table_entry(table, entry);
 981
 982         if (builtin >= 0) {
 983                 list = list->next;
 984                 if (list) {
 985                         entry = list->data;
 986                         entry->builtin = builtin;
 987                 }
 988
 989                 table->underflow[builtin] -= removed;
 990                 for (list = chain_tail; list; list = list->next) {
 991                         entry = list->data;
 992
 993                         builtin = entry->builtin;
 994                         if (builtin < 0)
 995                                 continue;
 996
 997                         table->hook_entry[builtin] -= removed;
 998                         table->underflow[builtin] -= removed;
 999                 }
1000         }
1001
1002         update_offsets(table);
1003
1004         return 0;
1005 }
1006
1007 static int iptables_compare_rule(struct connman_iptables *table,
1008                                 struct ipt_ip *ip, const char *chain_name,
1009                                 const char *target_name,
1010                                 struct xtables_target *xt_t,
1011                                 struct xtables_match *xt_m,
1012                                 struct xtables_rule_match *xt_rm)
1013 {
1014         struct connman_iptables_entry *entry;
1015         GList *found;
1016
1017         found = find_existing_rule(table, ip, chain_name, target_name,
1018                                                         xt_t, xt_m, xt_rm);
1019         if (found == NULL)
1020                 return -EINVAL;
1021
1022         entry = found->data;
1023         if (entry == NULL)
1024                 return -EINVAL;
1025
1026         return 0;
1027 }
1028
1029
1030 static int iptables_change_policy(struct connman_iptables *table,
1031                                 const char *chain_name, const char *policy)
1032 {
1033         GList *chain_head;
1034         struct connman_iptables_entry *entry;
1035         struct xt_entry_target *target;
1036         struct xt_standard_target *t;
1037         int verdict;
1038
1039         verdict = target_to_verdict(policy);
1040         if (verdict == 0)
1041                 return -EINVAL;
1042
1043         chain_head = find_chain_head(table, chain_name);
1044         if (chain_head == NULL)
1045                 return -EINVAL;
1046
1047         entry = chain_head->data;
1048         if (entry->builtin < 0)
1049                 return -EINVAL;
1050
1051         target = ipt_get_target(entry->entry);
1052
1053         t = (struct xt_standard_target *)target;
1054         t->verdict = verdict;
1055
1056         return 0;
1057 }
1058
1059 static struct ipt_replace *iptables_blob(struct connman_iptables *table)
1060 {
1061         struct ipt_replace *r;
1062         GList *list;
1063         struct connman_iptables_entry *e;
1064         unsigned char *entry_index;
1065
1066         r = g_try_malloc0(sizeof(struct ipt_replace) + table->size);
1067         if (r == NULL)
1068                 return NULL;
1069
1070         memset(r, 0, sizeof(*r) + table->size);
1071
1072         r->counters = g_try_malloc0(sizeof(struct xt_counters)
1073                                 * table->old_entries);
1074         if (r->counters == NULL) {
1075                 g_free(r);
1076                 return NULL;
1077         }
1078
1079         strcpy(r->name, table->info->name);
1080         r->num_entries = table->num_entries;
1081         r->size = table->size;
1082
1083         r->num_counters = table->old_entries;
1084         r->valid_hooks  = table->info->valid_hooks;
1085
1086         memcpy(r->hook_entry, table->hook_entry, sizeof(table->hook_entry));
1087         memcpy(r->underflow, table->underflow, sizeof(table->underflow));
1088
1089         entry_index = (unsigned char *)r->entries;
1090         for (list = table->entries; list; list = list->next) {
1091                 e = list->data;
1092
1093                 memcpy(entry_index, e->entry, e->entry->next_offset);
1094                 entry_index += e->entry->next_offset;
1095         }
1096
1097         return r;
1098 }
1099
1100 static void dump_ip(struct ipt_entry *entry)
1101 {
1102         struct ipt_ip *ip = &entry->ip;
1103         char ip_string[INET6_ADDRSTRLEN];
1104         char ip_mask[INET6_ADDRSTRLEN];
1105
1106         if (strlen(ip->iniface))
1107                 connman_info("\tin %s", ip->iniface);
1108
1109         if (strlen(ip->outiface))
1110                 connman_info("\tout %s", ip->outiface);
1111
1112         if (inet_ntop(AF_INET, &ip->src, ip_string, INET6_ADDRSTRLEN) != NULL &&
1113                         inet_ntop(AF_INET, &ip->smsk,
1114                                         ip_mask, INET6_ADDRSTRLEN) != NULL)
1115                 connman_info("\tsrc %s/%s", ip_string, ip_mask);
1116
1117         if (inet_ntop(AF_INET, &ip->dst, ip_string, INET6_ADDRSTRLEN) != NULL &&
1118                         inet_ntop(AF_INET, &ip->dmsk,
1119                                         ip_mask, INET6_ADDRSTRLEN) != NULL)
1120                 connman_info("\tdst %s/%s", ip_string, ip_mask);
1121 }
1122
1123 static void dump_target(struct connman_iptables *table,
1124                                 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                         connman_info("\ttarget RETURN");
1140                         break;
1141
1142                 case -NF_ACCEPT - 1:
1143                         connman_info("\ttarget ACCEPT");
1144                         break;
1145
1146                 case -NF_DROP - 1:
1147                         connman_info("\ttarget DROP");
1148                         break;
1149
1150                 case -NF_QUEUE - 1:
1151                         connman_info("\ttarget QUEUE");
1152                         break;
1153
1154                 case -NF_STOP - 1:
1155                         connman_info("\ttarget STOP");
1156                         break;
1157
1158                 default:
1159                         connman_info("\tJUMP @%p (0x%x)",
1160                                 (char*)table->blob_entries->entrytable +
1161                                 t->verdict, t->verdict);
1162                         break;
1163                 }
1164
1165                 xt_t = xtables_find_target(IPT_STANDARD_TARGET,
1166                                                 XTF_LOAD_MUST_SUCCEED);
1167
1168                 if(xt_t->print != NULL)
1169                         xt_t->print(NULL, target, 1);
1170         } else {
1171                 xt_t = xtables_find_target(target->u.user.name, XTF_TRY_LOAD);
1172                 if (xt_t == NULL) {
1173                         connman_info("\ttarget %s", target->u.user.name);
1174                         return;
1175                 }
1176
1177                 if(xt_t->print != NULL) {
1178                         connman_info("\ttarget ");
1179                         xt_t->print(NULL, target, 1);
1180                 }
1181         }
1182 }
1183
1184 static void dump_match(struct connman_iptables *table, struct ipt_entry *entry)
1185 {
1186         struct xtables_match *xt_m;
1187         struct xt_entry_match *match;
1188
1189         if (entry->elems == (unsigned char *)entry + entry->target_offset)
1190                 return;
1191
1192         match = (struct xt_entry_match *) entry->elems;
1193
1194         if (!strlen(match->u.user.name))
1195                 return;
1196
1197         xt_m = xtables_find_match(match->u.user.name, XTF_TRY_LOAD, NULL);
1198         if (xt_m == NULL)
1199                 goto out;
1200
1201         if(xt_m->print != NULL) {
1202                 connman_info("\tmatch ");
1203                 xt_m->print(NULL, match, 1);
1204
1205                 return;
1206         }
1207
1208 out:
1209         connman_info("\tmatch %s", match->u.user.name);
1210
1211 }
1212
1213 static int dump_entry(struct connman_iptables *table,
1214                         struct ipt_entry *entry, int builtin,
1215                         unsigned int hook, unsigned int offset,
1216                         void *user_data)
1217 {
1218         struct xt_entry_target *target;
1219
1220         target = ipt_get_target(entry);
1221
1222         if (entry_to_offset(table, entry) + entry->next_offset ==
1223                                         table->blob_entries->size) {
1224                 connman_info("End of CHAIN 0x%x", offset);
1225                 return 0;
1226         }
1227
1228         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET)) {
1229                 connman_info("USER CHAIN (%s) %p  match %p  target %p  size %d",
1230                         target->data, entry, entry->elems,
1231                         (char *)entry + entry->target_offset,
1232                                 entry->next_offset);
1233
1234                 return 0;
1235         } else if (builtin >= 0) {
1236                 connman_info("CHAIN (%s) %p  match %p  target %p  size %d",
1237                         hooknames[builtin], entry, entry->elems,
1238                         (char *)entry + entry->target_offset,
1239                                 entry->next_offset);
1240         } else {
1241                 connman_info("RULE %p  match %p  target %p  size %d", entry,
1242                         entry->elems,
1243                         (char *)entry + entry->target_offset,
1244                                 entry->next_offset);
1245         }
1246
1247         dump_match(table, entry);
1248         dump_target(table, entry);
1249         dump_ip(entry);
1250
1251         return 0;
1252 }
1253
1254 static void iptables_dump(struct connman_iptables *table)
1255 {
1256         connman_info("%s valid_hooks=0x%08x, num_entries=%u, size=%u",
1257                         table->info->name,
1258                         table->info->valid_hooks, table->info->num_entries,
1259                                 table->info->size);
1260
1261         iterate_entries(table, table->blob_entries->entrytable,
1262                         table->info->valid_hooks,
1263                         table->info->hook_entry,
1264                         table->blob_entries->size,
1265                         dump_entry, NULL);
1266
1267 }
1268
1269 static int iptables_get_entries(struct connman_iptables *table)
1270 {
1271         socklen_t entry_size;
1272
1273         entry_size = sizeof(struct ipt_get_entries) + table->info->size;
1274
1275         return getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_ENTRIES,
1276                                 table->blob_entries, &entry_size);
1277 }
1278
1279 static int iptables_replace(struct connman_iptables *table,
1280                                         struct ipt_replace *r)
1281 {
1282         return setsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_SET_REPLACE, r,
1283                          sizeof(*r) + r->size);
1284 }
1285
1286 static int add_entry(struct connman_iptables *table, struct ipt_entry *entry,
1287                         int builtin, unsigned int hook, unsigned offset,
1288                         void *user_data)
1289 {
1290         struct ipt_entry *new_entry;
1291
1292         new_entry = g_try_malloc0(entry->next_offset);
1293         if (new_entry == NULL)
1294                 return -ENOMEM;
1295
1296         memcpy(new_entry, entry, entry->next_offset);
1297
1298         return iptables_add_entry(table, new_entry, NULL, builtin);
1299 }
1300
1301 static void table_cleanup(struct connman_iptables *table)
1302 {
1303         GList *list;
1304         struct connman_iptables_entry *entry;
1305
1306         if (table == NULL)
1307                 return;
1308
1309         if (table->ipt_sock >= 0)
1310                 close(table->ipt_sock);
1311
1312         for (list = table->entries; list; list = list->next) {
1313                 entry = list->data;
1314
1315                 g_free(entry->entry);
1316                 g_free(entry);
1317         }
1318
1319         g_list_free(table->entries);
1320         g_free(table->info);
1321         g_free(table->blob_entries);
1322         g_free(table);
1323 }
1324
1325 static struct connman_iptables *iptables_init(const char *table_name)
1326 {
1327         struct connman_iptables *table = NULL;
1328         char *module = NULL;
1329         socklen_t s;
1330
1331         if (table_name == NULL)
1332                 table_name = "filter";
1333
1334         DBG("%s", table_name);
1335
1336         if (xtables_insmod("ip_tables", NULL, TRUE) != 0)
1337                 DBG("ip_tables module loading gives error but trying anyway");
1338
1339         module = g_strconcat("iptable_", table_name, NULL);
1340         if (module == NULL)
1341                 return NULL;
1342
1343         if (xtables_insmod(module, NULL, TRUE) != 0)
1344                 DBG("%s module loading gives error but trying anyway", module);
1345
1346         g_free(module);
1347
1348         table = g_hash_table_lookup(table_hash, table_name);
1349         if (table != NULL)
1350                 return table;
1351
1352         table = g_try_new0(struct connman_iptables, 1);
1353         if (table == NULL)
1354                 return NULL;
1355
1356         table->info = g_try_new0(struct ipt_getinfo, 1);
1357         if (table->info == NULL)
1358                 goto err;
1359
1360         table->ipt_sock = socket(AF_INET, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_RAW);
1361         if (table->ipt_sock < 0)
1362                 goto err;
1363
1364         s = sizeof(*table->info);
1365         strcpy(table->info->name, table_name);
1366         if (getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_INFO,
1367                                                 table->info, &s) < 0) {
1368                 connman_error("iptables support missing error %d (%s)", errno,
1369                         strerror(errno));
1370                 goto err;
1371         }
1372
1373         table->blob_entries = g_try_malloc0(sizeof(struct ipt_get_entries) +
1374                                                 table->info->size);
1375         if (table->blob_entries == NULL)
1376                 goto err;
1377
1378         strcpy(table->blob_entries->name, table_name);
1379         table->blob_entries->size = table->info->size;
1380
1381         if (iptables_get_entries(table) < 0)
1382                 goto err;
1383
1384         table->num_entries = 0;
1385         table->old_entries = table->info->num_entries;
1386         table->size = 0;
1387
1388         memcpy(table->underflow, table->info->underflow,
1389                                 sizeof(table->info->underflow));
1390         memcpy(table->hook_entry, table->info->hook_entry,
1391                                 sizeof(table->info->hook_entry));
1392
1393         iterate_entries(table, table->blob_entries->entrytable,
1394                         table->info->valid_hooks, table->info->hook_entry,
1395                         table->blob_entries->size, add_entry, NULL);
1396
1397         g_hash_table_insert(table_hash, g_strdup(table_name), table);
1398
1399         return table;
1400
1401 err:
1402         table_cleanup(table);
1403
1404         return NULL;
1405 }
1406
1407 static struct option iptables_opts[] = {
1408         {.name = "append",        .has_arg = 1, .val = 'A'},
1409         {.name = "compare",       .has_arg = 1, .val = 'C'},
1410         {.name = "delete",        .has_arg = 1, .val = 'D'},
1411         {.name = "flush-chain",   .has_arg = 1, .val = 'F'},
1412         {.name = "insert",        .has_arg = 1, .val = 'I'},
1413         {.name = "list",          .has_arg = 2, .val = 'L'},
1414         {.name = "new-chain",     .has_arg = 1, .val = 'N'},
1415         {.name = "policy",        .has_arg = 1, .val = 'P'},
1416         {.name = "delete-chain",  .has_arg = 1, .val = 'X'},
1417         {.name = "destination",   .has_arg = 1, .val = 'd'},
1418         {.name = "in-interface",  .has_arg = 1, .val = 'i'},
1419         {.name = "jump",          .has_arg = 1, .val = 'j'},
1420         {.name = "match",         .has_arg = 1, .val = 'm'},
1421         {.name = "out-interface", .has_arg = 1, .val = 'o'},
1422         {.name = "source",        .has_arg = 1, .val = 's'},
1423         {.name = "table",         .has_arg = 1, .val = 't'},
1424         {NULL},
1425 };
1426
1427 struct xtables_globals iptables_globals = {
1428         .option_offset = 0,
1429         .opts = iptables_opts,
1430         .orig_opts = iptables_opts,
1431 };
1432
1433 static struct xtables_target *prepare_target(struct connman_iptables *table,
1434                                                         const char *target_name)
1435 {
1436         struct xtables_target *xt_t = NULL;
1437         gboolean is_builtin, is_user_defined;
1438         GList *chain_head = NULL;
1439         size_t target_size;
1440
1441         is_builtin = FALSE;
1442         is_user_defined = FALSE;
1443
1444         if (is_builtin_target(target_name))
1445                 is_builtin = TRUE;
1446         else {
1447                 chain_head = find_chain_head(table, target_name);
1448                 if (chain_head != NULL && chain_head->next != NULL)
1449                         is_user_defined = TRUE;
1450         }
1451
1452         if (is_builtin || is_user_defined)
1453                 xt_t = xtables_find_target(IPT_STANDARD_TARGET,
1454                                                 XTF_LOAD_MUST_SUCCEED);
1455         else
1456                 xt_t = xtables_find_target(target_name, XTF_TRY_LOAD);
1457
1458         if (xt_t == NULL)
1459                 return NULL;
1460
1461         target_size = ALIGN(sizeof(struct ipt_entry_target)) + xt_t->size;
1462
1463         xt_t->t = g_try_malloc0(target_size);
1464         if (xt_t->t == NULL)
1465                 return NULL;
1466
1467         xt_t->t->u.target_size = target_size;
1468
1469         if (is_builtin || is_user_defined) {
1470                 struct xt_standard_target *target;
1471
1472                 target = (struct xt_standard_target *)(xt_t->t);
1473                 strcpy(target->target.u.user.name, IPT_STANDARD_TARGET);
1474
1475                 if (is_builtin == TRUE)
1476                         target->verdict = target_to_verdict(target_name);
1477                 else if (is_user_defined == TRUE) {
1478                         struct connman_iptables_entry *target_rule;
1479
1480                         if (chain_head == NULL) {
1481                                 g_free(xt_t->t);
1482                                 return NULL;
1483                         }
1484
1485                         target_rule = chain_head->next->data;
1486                         target->verdict = target_rule->offset;
1487                 }
1488         } else {
1489                 strcpy(xt_t->t->u.user.name, target_name);
1490                 xt_t->t->u.user.revision = xt_t->revision;
1491                 if (xt_t->init != NULL)
1492                         xt_t->init(xt_t->t);
1493         }
1494
1495 #if XTABLES_VERSION_CODE > 5
1496         if (xt_t->x6_options != NULL)
1497                 iptables_globals.opts =
1498                         xtables_options_xfrm(
1499                                 iptables_globals.orig_opts,
1500                                 iptables_globals.opts,
1501                                 xt_t->x6_options,
1502                                 &xt_t->option_offset);
1503         else
1504 #endif
1505                 iptables_globals.opts =
1506                         xtables_merge_options(
1507 #if XTABLES_VERSION_CODE > 5
1508                                 iptables_globals.orig_opts,
1509 #endif
1510                                 iptables_globals.opts,
1511                                 xt_t->extra_opts,
1512                                 &xt_t->option_offset);
1513
1514         if (iptables_globals.opts == NULL) {
1515                 g_free(xt_t->t);
1516                 xt_t = NULL;
1517         }
1518
1519         return xt_t;
1520 }
1521
1522 static struct xtables_match *prepare_matches(struct connman_iptables *table,
1523                                         struct xtables_rule_match **xt_rm,
1524                                         const char *match_name)
1525 {
1526         struct xtables_match *xt_m;
1527         size_t match_size;
1528
1529         if (match_name == NULL)
1530                 return NULL;
1531
1532         xt_m = xtables_find_match(match_name, XTF_LOAD_MUST_SUCCEED, xt_rm);
1533         match_size = ALIGN(sizeof(struct ipt_entry_match)) + xt_m->size;
1534
1535         xt_m->m = g_try_malloc0(match_size);
1536         if (xt_m->m == NULL)
1537                 return NULL;
1538
1539         xt_m->m->u.match_size = match_size;
1540         strcpy(xt_m->m->u.user.name, xt_m->name);
1541         xt_m->m->u.user.revision = xt_m->revision;
1542
1543         if (xt_m->init != NULL)
1544                 xt_m->init(xt_m->m);
1545
1546         if (xt_m == xt_m->next)
1547                 goto done;
1548
1549 #if XTABLES_VERSION_CODE > 5
1550         if (xt_m->x6_options != NULL)
1551                 iptables_globals.opts =
1552                         xtables_options_xfrm(
1553                                 iptables_globals.orig_opts,
1554                                 iptables_globals.opts,
1555                                 xt_m->x6_options,
1556                                 &xt_m->option_offset);
1557         else
1558 #endif
1559                         iptables_globals.opts =
1560                         xtables_merge_options(
1561 #if XTABLES_VERSION_CODE > 5
1562                                 iptables_globals.orig_opts,
1563 #endif
1564                                 iptables_globals.opts,
1565                                 xt_m->extra_opts,
1566                                 &xt_m->option_offset);
1567
1568         if (iptables_globals.opts == NULL) {
1569                 g_free(xt_m->m);
1570                 xt_m = NULL;
1571         }
1572
1573 done:
1574         return xt_m;
1575 }
1576
1577 static int parse_ip_and_mask(const char *str, struct in_addr *ip, struct in_addr *mask)
1578 {
1579         char **tokens;
1580         uint32_t prefixlength;
1581         uint32_t tmp;
1582         int err;
1583
1584         tokens = g_strsplit(str, "/", 2);
1585         if (tokens == NULL)
1586                 return -1;
1587
1588         if (!inet_pton(AF_INET, tokens[0], ip)) {
1589                 err = -1;
1590                 goto out;
1591         }
1592
1593         if (tokens[1] != NULL) {
1594                 prefixlength = strtol(tokens[1], NULL, 10);
1595                 if (prefixlength > 31) {
1596                         err = -1;
1597                         goto out;
1598                 }
1599
1600                 tmp = ~(0xffffffff >> prefixlength);
1601         } else {
1602                 tmp = 0xffffffff;
1603         }
1604
1605         mask->s_addr = htonl(tmp);
1606         ip->s_addr = ip->s_addr & mask->s_addr;
1607         err = 0;
1608 out:
1609         g_strfreev(tokens);
1610
1611         return err;
1612 }
1613
1614 static struct connman_iptables *pre_load_table(const char *table_name,
1615                                         struct connman_iptables *table)
1616 {
1617         if (table != NULL)
1618                 return table;
1619
1620         return iptables_init(table_name);
1621 }
1622
1623 static void clear_tables_flags(void)
1624 {
1625         struct xtables_match *xt_m;
1626         struct xtables_target *xt_t;
1627
1628         /*
1629          * Clear all flags because the flags are only valid
1630          * for one rule.
1631          */
1632         for (xt_m = xtables_matches; xt_m != NULL; xt_m = xt_m->next)
1633                 xt_m->mflags = 0;
1634
1635         for (xt_t = xtables_targets; xt_t != NULL; xt_t = xt_t->next) {
1636                 xt_t->tflags = 0;
1637                 xt_t->used = 0;
1638         }
1639 }
1640
1641 static int iptables_command(int argc, char *argv[])
1642 {
1643         struct connman_iptables *table;
1644         struct xtables_rule_match *xt_rm, *tmp_xt_rm;
1645         struct xtables_match *xt_m, *xt_m_t;
1646         struct xtables_target *xt_t;
1647         struct ipt_ip ip;
1648         char *table_name, *chain, *new_chain, *match_name, *target_name;
1649         char *flush_chain, *delete_chain, *policy;
1650         int c, ret, in_len, out_len;
1651         gboolean dump, invert, insert, delete, compare;
1652
1653         if (argc == 0)
1654                 return -EINVAL;
1655
1656         dump = FALSE;
1657         invert = FALSE;
1658         insert = FALSE;
1659         delete = FALSE;
1660         compare = FALSE;
1661         chain = new_chain = match_name = target_name = NULL;
1662         flush_chain = delete_chain = policy = table_name = NULL;
1663         memset(&ip, 0, sizeof(struct ipt_ip));
1664         table = NULL;
1665         xt_rm = NULL;
1666         xt_m = NULL;
1667         xt_t = NULL;
1668         /* Default code for options parsing */
1669         ret = -EINVAL;
1670
1671         clear_tables_flags();
1672
1673         /* extension's options will generate false-positives errors */
1674         opterr = 0;
1675
1676         optind = 0;
1677
1678         while ((c = getopt_long(argc, argv,
1679                                         "-A:C:D:F:I:L::N:P:X:d:j:i:m:o:s:t:",
1680                                         iptables_globals.opts, NULL)) != -1) {
1681                 switch (c) {
1682                 case 'A':
1683                         /* It is either -A, -C, -D or -I at once */
1684                         if (chain)
1685                                 goto out;
1686
1687                         chain = optarg;
1688                         break;
1689
1690                 case 'C':
1691                         /* It is either -A, -C, -D or -I at once */
1692                         if (chain)
1693                                 goto out;
1694
1695                         chain = optarg;
1696                         compare = TRUE;
1697                         break;
1698
1699                 case 'D':
1700                         /* It is either -A, -C, -D or -I at once */
1701                         if (chain)
1702                                 goto out;
1703
1704                         chain = optarg;
1705                         delete = TRUE;
1706                         break;
1707
1708                 case 'F':
1709                         flush_chain = optarg;
1710                         break;
1711
1712                 case 'I':
1713                         /* It is either -A, -C, -D or -I at once */
1714                         if (chain)
1715                                 goto out;
1716
1717                         chain = optarg;
1718                         insert = TRUE;
1719                         break;
1720
1721                 case 'L':
1722                         dump = TRUE;
1723                         break;
1724
1725                 case 'N':
1726                         new_chain = optarg;
1727                         break;
1728
1729                 case 'P':
1730                         chain = optarg;
1731                         if (optind < argc)
1732                                 policy = argv[optind++];
1733                         else
1734                                 goto out;
1735
1736                         break;
1737
1738                 case 'X':
1739                         delete_chain = optarg;
1740                         break;
1741
1742                 case 'd':
1743                         if (!parse_ip_and_mask(optarg, &ip.dst, &ip.dmsk))
1744                                 break;
1745
1746                         if (invert)
1747                                 ip.invflags |= IPT_INV_DSTIP;
1748
1749                         break;
1750
1751                 case 'i':
1752                         in_len = strlen(optarg);
1753
1754                         if (in_len + 1 > IFNAMSIZ)
1755                                 break;
1756
1757                         strcpy(ip.iniface, optarg);
1758                         memset(ip.iniface_mask, 0xff, in_len + 1);
1759
1760                         if (invert)
1761                                 ip.invflags |= IPT_INV_VIA_IN;
1762
1763                         break;
1764
1765                 case 'j':
1766                         target_name = optarg;
1767
1768                         table = pre_load_table(table_name, table);
1769                         if (table == NULL)
1770                                 goto out;
1771
1772                         xt_t = prepare_target(table, target_name);
1773                         if (xt_t == NULL)
1774                                 goto out;
1775
1776                         break;
1777
1778                 case 'm':
1779                         match_name = optarg;
1780
1781                         table = pre_load_table(table_name, table);
1782                         if (table == NULL)
1783                                 goto out;
1784
1785                         xt_m = prepare_matches(table, &xt_rm, match_name);
1786                         if (xt_m == NULL)
1787                                 goto out;
1788
1789                         break;
1790
1791                 case 'o':
1792                         out_len = strlen(optarg);
1793
1794                         if (out_len + 1 > IFNAMSIZ)
1795                                 break;
1796
1797                         strcpy(ip.outiface, optarg);
1798                         memset(ip.outiface_mask, 0xff, out_len + 1);
1799
1800                         if (invert)
1801                                 ip.invflags |= IPT_INV_VIA_OUT;
1802
1803                         break;
1804
1805                 case 's':
1806                         if (!parse_ip_and_mask(optarg, &ip.src, &ip.smsk))
1807                                 break;
1808
1809                         if (invert)
1810                                 ip.invflags |= IPT_INV_SRCIP;
1811
1812                         break;
1813
1814                 case 't':
1815                         table_name = optarg;
1816
1817                         table = pre_load_table(table_name, table);
1818                         if (table == NULL)
1819                                 goto out;
1820
1821                         break;
1822
1823                 case 1:
1824                         if (optarg[0] == '!' && optarg[1] == '\0') {
1825                                 invert = TRUE;
1826                                 optarg[0] = '\0';
1827                                 continue;
1828                         }
1829
1830                         connman_error("Invalid option");
1831
1832                         goto out;
1833
1834                 default:
1835 #if XTABLES_VERSION_CODE > 5
1836                         if (xt_t != NULL && (xt_t->x6_parse != NULL ||
1837                                                 xt_t->parse != NULL) &&
1838                                         (c >= (int) xt_t->option_offset &&
1839                                         c < (int) xt_t->option_offset +
1840                                         XT_OPTION_OFFSET_SCALE)) {
1841                                 xtables_option_tpcall(c, argv,
1842                                                         invert, xt_t, NULL);
1843
1844                                 break;
1845                         }
1846
1847                         for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL;
1848                                                 tmp_xt_rm = tmp_xt_rm->next) {
1849                                 xt_m_t = tmp_xt_rm->match;
1850
1851                                 if (tmp_xt_rm->completed ||
1852                                                 (xt_m_t->x6_parse == NULL &&
1853                                                  xt_m_t->parse == NULL))
1854                                         continue;
1855
1856                                 if (c < (int) xt_m_t->option_offset ||
1857                                         c >= (int) xt_m_t->option_offset
1858                                         + XT_OPTION_OFFSET_SCALE)
1859                                         continue;
1860
1861                                 xtables_option_mpcall(c, argv,
1862                                                         invert, xt_m_t, NULL);
1863
1864                                 break;
1865                         }
1866 #else
1867                         if (xt_t == NULL || xt_t->parse == NULL ||
1868                                 !xt_t->parse(c - xt_t->option_offset,
1869                                 argv, invert, &xt_t->tflags, NULL, &xt_t->t)) {
1870
1871                                 for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL;
1872                                                 tmp_xt_rm = tmp_xt_rm->next) {
1873                                         xt_m_t = tmp_xt_rm->match;
1874
1875                                         if (tmp_xt_rm->completed ||
1876                                                         xt_m_t->parse == NULL)
1877                                                 continue;
1878
1879                                         if (xt_m->parse(c - xt_m->option_offset,
1880                                                 argv, invert, &xt_m->mflags,
1881                                                 NULL, &xt_m->m))
1882                                                 break;
1883                                 }
1884                         }
1885 #endif
1886                         break;
1887                 }
1888
1889                 invert = FALSE;
1890         }
1891
1892 #if XTABLES_VERSION_CODE > 5
1893         for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL;
1894                                 tmp_xt_rm = tmp_xt_rm->next)
1895                 xtables_option_mfcall(tmp_xt_rm->match);
1896
1897         if (xt_t != NULL)
1898                 xtables_option_tfcall(xt_t);
1899 #else
1900         for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL;
1901                                 tmp_xt_rm = tmp_xt_rm->next)
1902                 if (tmp_xt_rm->match->final_check != NULL)
1903                         tmp_xt_rm->match->final_check(
1904                                         tmp_xt_rm->match->mflags);
1905
1906         if (xt_t != NULL && xt_t->final_check != NULL)
1907                 xt_t->final_check(xt_t->tflags);
1908 #endif
1909
1910         table = pre_load_table(table_name, table);
1911         if (table == NULL)
1912                 goto out;
1913
1914         /* Option parsing went fine, falling back to succes code */
1915         ret = 0;
1916
1917         if (delete_chain != NULL) {
1918                 printf("Delete chain %s\n", delete_chain);
1919
1920                 iptables_delete_chain(table, delete_chain);
1921
1922                 goto out;
1923         }
1924
1925         if (dump) {
1926                 iptables_dump(table);
1927
1928                 goto out;
1929         }
1930
1931         if (flush_chain) {
1932                 DBG("Flush chain %s", flush_chain);
1933
1934                 iptables_flush_chain(table, flush_chain);
1935
1936                 goto out;
1937         }
1938
1939         if (chain && new_chain) {
1940                 ret = -EINVAL;
1941                 goto out;
1942         }
1943
1944         if (new_chain) {
1945                 DBG("New chain %s", new_chain);
1946
1947                 ret = iptables_add_chain(table, new_chain);
1948                 goto out;
1949         }
1950
1951         if (chain) {
1952                 if (policy != NULL) {
1953                         printf("Changing policy of %s to %s\n", chain, policy);
1954
1955                         iptables_change_policy(table, chain, policy);
1956
1957                         goto out;
1958                 }
1959
1960                 if (xt_t == NULL)
1961                         goto out;
1962
1963                 if (compare == TRUE) {
1964                         ret = iptables_compare_rule(table, &ip, chain,
1965                                         target_name, xt_t, xt_m, xt_rm);
1966                         goto out;
1967                 }
1968
1969                 if (delete == TRUE) {
1970                         DBG("Deleting %s to %s (match %s)\n",
1971                                         target_name, chain, match_name);
1972
1973                         ret = iptables_delete_rule(table, &ip, chain,
1974                                         target_name, xt_t, xt_m, xt_rm);
1975
1976                         goto out;
1977                 }
1978
1979                 if (insert == TRUE) {
1980                         DBG("Inserting %s to %s (match %s)",
1981                                         target_name, chain, match_name);
1982
1983                         ret = iptables_insert_rule(table, &ip, chain,
1984                                                 target_name, xt_t, xt_rm);
1985
1986                         goto out;
1987                 } else {
1988                         DBG("Adding %s to %s (match %s)",
1989                                         target_name, chain, match_name);
1990
1991                         ret = iptables_append_rule(table, &ip, chain,
1992                                                 target_name, xt_t, xt_rm);
1993
1994                         goto out;
1995                 }
1996         }
1997
1998 out:
1999         if (xt_t)
2000                 g_free(xt_t->t);
2001
2002         if (xt_m)
2003                 g_free(xt_m->m);
2004
2005         return ret;
2006 }
2007
2008 int __connman_iptables_command(const char *format, ...)
2009 {
2010         char **argv, **arguments, *command;
2011         int argc, i, ret;
2012         va_list args;
2013
2014         if (format == NULL)
2015                 return -EINVAL;
2016
2017         va_start(args, format);
2018
2019         command = g_strdup_vprintf(format, args);
2020
2021         va_end(args);
2022
2023         if (command == NULL)
2024                 return -ENOMEM;
2025
2026         arguments = g_strsplit_set(command, " ", -1);
2027
2028         for (argc = 0; arguments[argc]; argc++);
2029         ++argc;
2030
2031         DBG("command %s argc %d", command, argc);
2032
2033         argv = g_try_malloc0(argc * sizeof(char *));
2034         if (argv == NULL) {
2035                 g_free(command);
2036                 g_strfreev(arguments);
2037                 return -ENOMEM;
2038         }
2039
2040         argv[0] = "iptables";
2041         for (i = 1; i < argc; i++)
2042                 argv[i] = arguments[i - 1];
2043
2044         ret = iptables_command(argc, argv);
2045
2046         g_free(command);
2047         g_strfreev(arguments);
2048         g_free(argv);
2049
2050         return ret;
2051 }
2052
2053
2054 int __connman_iptables_commit(const char *table_name)
2055 {
2056         struct connman_iptables *table;
2057         struct ipt_replace *repl;
2058         int err;
2059
2060         DBG("%s", table_name);
2061
2062         table = g_hash_table_lookup(table_hash, table_name);
2063         if (table == NULL)
2064                 return -EINVAL;
2065
2066         repl = iptables_blob(table);
2067
2068         err = iptables_replace(table, repl);
2069
2070         g_free(repl->counters);
2071         g_free(repl);
2072
2073         if (err < 0)
2074             return err;
2075
2076         g_hash_table_remove(table_hash, table_name);
2077
2078         return 0;
2079 }
2080
2081 static void remove_table(gpointer user_data)
2082 {
2083         struct connman_iptables *table = user_data;
2084
2085         table_cleanup(table);
2086 }
2087
2088 int __connman_iptables_init(void)
2089 {
2090         DBG("");
2091
2092         table_hash = g_hash_table_new_full(g_str_hash, g_str_equal,
2093                                                 g_free, remove_table);
2094
2095         xtables_init_all(&iptables_globals, NFPROTO_IPV4);
2096
2097         return 0;
2098
2099 }
2100
2101 void __connman_iptables_cleanup(void)
2102 {
2103         DBG("");
2104
2105         g_hash_table_destroy(table_hash);
2106
2107         xtables_free_opts(1);
2108 }