src/iptables.c

   1 /*
   2  *
   3  *  Connection Manager
   4  *
   5  *  Copyright (C) 2007-2010  Intel Corporation. All rights reserved.
   6  *
   7  *  This program is free software; you can redistribute it and/or modify
   8  *  it under the terms of the GNU General Public License version 2 as
   9  *  published by the Free Software Foundation.
  10  *
  11  *  This program is distributed in the hope that it will be useful,
  12  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  *  GNU General Public License for more details.
  15  *
  16  *  You should have received a copy of the GNU General Public License
  17  *  along with this program; if not, write to the Free Software
  18  *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
  19  *
  20  */
  21
  22 #ifdef HAVE_CONFIG_H
  23 #include <config.h>
  24 #endif
  25
  26 #include <getopt.h>
  27 #include <stdlib.h>
  28 #include <stdio.h>
  29 #include <string.h>
  30 #include <unistd.h>
  31 #include <sys/errno.h>
  32 #include <sys/socket.h>
  33 #include <xtables.h>
  34
  35 #include <linux/netfilter_ipv4/ip_tables.h>
  36
  37 #include "connman.h"
  38
  39
  40 static const char *hooknames[] = {
  41         [NF_IP_PRE_ROUTING]     = "PREROUTING",
  42         [NF_IP_LOCAL_IN]        = "INPUT",
  43         [NF_IP_FORWARD]         = "FORWARD",
  44         [NF_IP_LOCAL_OUT]       = "OUTPUT",
  45         [NF_IP_POST_ROUTING]    = "POSTROUTING",
  46 };
  47
  48 #define LABEL_ACCEPT  "ACCEPT"
  49 #define LABEL_DROP    "DROP"
  50 #define LABEL_QUEUE   "QUEUE"
  51 #define LABEL_RETURN  "RETURN"
  52
  53 /* fn returns 0 to continue iteration */
  54 #define _XT_ENTRY_ITERATE_CONTINUE(type, entries, size, n, fn, args...) \
  55 ({                                                              \
  56         unsigned int __i;                                       \
  57         int __n;                                                \
  58         int __ret = 0;                                          \
  59         type *__entry;                                          \
  60                                                                 \
  61         for (__i = 0, __n = 0; __i < (size);                    \
  62              __i += __entry->next_offset, __n++) {              \
  63                 __entry = (void *)(entries) + __i;              \
  64                 if (__n < n)                                    \
  65                         continue;                               \
  66                                                                 \
  67                 __ret = fn(__entry,  ## args);                  \
  68                 if (__ret != 0)                                 \
  69                         break;                                  \
  70         }                                                       \
  71         __ret;                                                  \
  72 })
  73
  74 /* fn returns 0 to continue iteration */
  75 #define _XT_ENTRY_ITERATE(type, entries, size, fn, args...) \
  76         _XT_ENTRY_ITERATE_CONTINUE(type, entries, size, 0, fn, args)
  77
  78 #define ENTRY_ITERATE(entries, size, fn, args...) \
  79         _XT_ENTRY_ITERATE(struct ipt_entry, entries, size, fn, ## args)
  80
  81 #define MIN_ALIGN (__alignof__(struct ipt_entry))
  82
  83 #define ALIGN(s) (((s) + ((MIN_ALIGN)-1)) & ~((MIN_ALIGN)-1))
  84
  85 struct ipt_error_target {
  86         struct xt_entry_target t;
  87         char error[IPT_TABLE_MAXNAMELEN];
  88 };
  89
  90 struct connman_iptables_entry {
  91         int offset;
  92         int builtin;
  93
  94         struct ipt_entry *entry;
  95 };
  96
  97 struct connman_iptables {
  98         int ipt_sock;
  99
 100         struct ipt_getinfo *info;
 101         struct ipt_get_entries *blob_entries;
 102
 103         unsigned int num_entries;
 104         unsigned int old_entries;
 105         unsigned int size;
 106
 107         unsigned int underflow[NF_INET_NUMHOOKS];
 108         unsigned int hook_entry[NF_INET_NUMHOOKS];
 109
 110         GList *entries;
 111 };
 112
 113 static GHashTable *table_hash = NULL;
 114
 115 static struct ipt_entry *get_entry(struct connman_iptables *table,
 116                                         unsigned int offset)
 117 {
 118         return (struct ipt_entry *)((char *)table->blob_entries->entrytable +
 119                                                                         offset);
 120 }
 121
 122 static int is_hook_entry(struct connman_iptables *table,
 123                                 struct ipt_entry *entry)
 124 {
 125         unsigned int i;
 126
 127         for (i = 0; i < NF_INET_NUMHOOKS; i++) {
 128                 if ((table->info->valid_hooks & (1 << i))
 129                 && get_entry(table, table->info->hook_entry[i]) == entry)
 130                         return i;
 131         }
 132
 133         return -1;
 134 }
 135
 136 static unsigned long entry_to_offset(struct connman_iptables *table,
 137                                         struct ipt_entry *entry)
 138 {
 139         return (void *)entry - (void *)table->blob_entries->entrytable;
 140 }
 141
 142 static int target_to_verdict(char *target_name)
 143 {
 144         if (!strcmp(target_name, LABEL_ACCEPT))
 145                 return -NF_ACCEPT - 1;
 146
 147         if (!strcmp(target_name, LABEL_DROP))
 148                 return -NF_DROP - 1;
 149
 150         if (!strcmp(target_name, LABEL_QUEUE))
 151                 return -NF_QUEUE - 1;
 152
 153         if (!strcmp(target_name, LABEL_RETURN))
 154                 return XT_RETURN;
 155
 156         return 0;
 157 }
 158
 159 static gboolean is_builtin_target(char *target_name)
 160 {
 161         if (!strcmp(target_name, LABEL_ACCEPT) ||
 162                 !strcmp(target_name, LABEL_DROP) ||
 163                 !strcmp(target_name, LABEL_QUEUE) ||
 164                 !strcmp(target_name, LABEL_RETURN))
 165                 return TRUE;
 166
 167         return FALSE;
 168 }
 169
 170 static gboolean is_jump(struct connman_iptables_entry *e)
 171 {
 172         struct xt_entry_target *target;
 173
 174         target = ipt_get_target(e->entry);
 175
 176         if (!strcmp(target->u.user.name, IPT_STANDARD_TARGET)) {
 177                 struct xt_standard_target *t;
 178
 179                 t = (struct xt_standard_target *)target;
 180
 181                 switch (t->verdict) {
 182                 case XT_RETURN:
 183                 case -NF_ACCEPT - 1:
 184                 case -NF_DROP - 1:
 185                 case -NF_QUEUE - 1:
 186                 case -NF_STOP - 1:
 187                         return false;
 188
 189                 default:
 190                         return true;
 191                 }
 192         }
 193
 194         return false;
 195 }
 196
 197 static gboolean is_chain(struct connman_iptables *table,
 198                                 struct connman_iptables_entry *e)
 199 {
 200         struct ipt_entry *entry;
 201         struct xt_entry_target *target;
 202
 203         entry = e->entry;
 204         if (e->builtin >= 0)
 205                 return TRUE;
 206
 207         target = ipt_get_target(entry);
 208         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET))
 209                 return TRUE;
 210
 211         return FALSE;
 212 }
 213
 214 static GList *find_chain_head(struct connman_iptables *table,
 215                                 char *chain_name)
 216 {
 217         GList *list;
 218         struct connman_iptables_entry *head;
 219         struct ipt_entry *entry;
 220         struct xt_entry_target *target;
 221         int builtin;
 222
 223         for (list = table->entries; list; list = list->next) {
 224                 head = list->data;
 225                 entry = head->entry;
 226
 227                 /* Buit-in chain */
 228                 builtin = head->builtin;
 229                 if (builtin >= 0 && !strcmp(hooknames[builtin], chain_name))
 230                         break;
 231
 232                 /* User defined chain */
 233                 target = ipt_get_target(entry);
 234                 if (!strcmp(target->u.user.name, IPT_ERROR_TARGET) &&
 235                     !strcmp((char *)target->data, chain_name))
 236                         break;
 237         }
 238
 239         return list;
 240 }
 241
 242 static GList *find_chain_tail(struct connman_iptables *table,
 243                                 char *chain_name)
 244 {
 245         GList *chain_head, *list;
 246         struct connman_iptables_entry *head, *tail;
 247         struct ipt_entry *entry;
 248         struct xt_entry_target *target;
 249         int builtin;
 250
 251         /* First we look for the head */
 252         for (list = table->entries; list; list = list->next) {
 253                 head = list->data;
 254                 entry = head->entry;
 255
 256                 /* Buit-in chain */
 257                 builtin = head->builtin;
 258                 if (builtin >= 0 && !strcmp(hooknames[builtin], chain_name))
 259                         break;
 260
 261                 /* User defined chain */
 262                 target = ipt_get_target(entry);
 263                 if (!strcmp(target->u.user.name, IPT_ERROR_TARGET) &&
 264                     !strcmp((char *)target->data, chain_name))
 265                         break;
 266         }
 267
 268         if (list == NULL)
 269                 return NULL;
 270
 271         chain_head = list;
 272
 273         /* Then we look for the next chain */
 274         for (list = chain_head->next; list; list = list->next) {
 275                 tail = list->data;
 276                 entry = tail->entry;
 277
 278                 if (is_chain(table, tail))
 279                         return list;
 280         }
 281
 282         /* Nothing found, we return the table end */
 283         return g_list_last(table->entries);
 284 }
 285
 286
 287 static void update_offsets(struct connman_iptables *table)
 288 {
 289         GList *list, *prev;
 290         struct connman_iptables_entry *entry, *prev_entry;
 291
 292         for (list = table->entries; list; list = list->next) {
 293                 entry = list->data;
 294
 295                 if (list == table->entries) {
 296                         entry->offset = 0;
 297
 298                         continue;
 299                 }
 300
 301                 prev = list->prev;
 302                 prev_entry = prev->data;
 303
 304                 entry->offset = prev_entry->offset +
 305                                         prev_entry->entry->next_offset;
 306         }
 307 }
 308
 309 static int iptables_add_entry(struct connman_iptables *table,
 310                                 struct ipt_entry *entry, GList *before,
 311                                         int builtin)
 312 {
 313         GList *list;
 314         struct connman_iptables_entry *e, *tmp, *entry_before;
 315         struct xt_standard_target *t;
 316
 317         if (table == NULL)
 318                 return -1;
 319
 320         e = g_try_malloc0(sizeof(struct connman_iptables_entry));
 321         if (e == NULL)
 322                 return -1;
 323
 324         e->entry = entry;
 325         e->builtin = builtin;
 326
 327         table->entries = g_list_insert_before(table->entries, before, e);
 328         table->num_entries++;
 329         table->size += entry->next_offset;
 330
 331         if (before == NULL) {
 332                 e->offset = table->size - entry->next_offset;
 333
 334                 return 0;
 335         }
 336
 337         entry_before = before->data;
 338
 339         /*
 340          * We've just insterted a new entry. All references before it
 341          * should be bumped accordingly.
 342          */
 343         for (list = table->entries; list != before; list = list->next) {
 344                 tmp = list->data;
 345
 346                 if (!is_jump(tmp))
 347                         continue;
 348
 349                 t = (struct xt_standard_target *)ipt_get_target(tmp->entry);
 350
 351                 if (t->verdict >= entry_before->offset)
 352                         t->verdict += entry->next_offset;
 353         }
 354
 355         update_offsets(table);
 356
 357         return 0;
 358 }
 359
 360 static int iptables_add_chain(struct connman_iptables *table,
 361                                         char *name)
 362 {
 363         GList *last;
 364         struct ipt_entry *entry_head;
 365         struct ipt_entry *entry_return;
 366         struct ipt_error_target *error;
 367         struct ipt_standard_target *standard;
 368         u_int16_t entry_head_size, entry_return_size;
 369
 370         last = g_list_last(table->entries);
 371
 372         /*
 373          * An empty chain is composed of:
 374          * - A head entry, with no match and an error target.
 375          *   The error target data is the chain name.
 376          * - A tail entry, with no match and a standard target.
 377          *   The standard target verdict is XT_RETURN (return to the
 378          *   caller).
 379          */
 380
 381         /* head entry */
 382         entry_head_size = sizeof(struct ipt_entry) +
 383                                 sizeof(struct ipt_error_target);
 384         entry_head = g_try_malloc0(entry_head_size);
 385         if (entry_head == NULL)
 386                 goto err;
 387
 388         memset(entry_head, 0, entry_head_size);
 389
 390         entry_head->target_offset = sizeof(struct ipt_entry);
 391         entry_head->next_offset = entry_head_size;
 392
 393         error = (struct ipt_error_target *) entry_head->elems;
 394         strcpy(error->t.u.user.name, IPT_ERROR_TARGET);
 395         error->t.u.user.target_size = ALIGN(sizeof(struct ipt_error_target));
 396         strcpy(error->error, name);
 397
 398         if (iptables_add_entry(table, entry_head, last, -1) < 0)
 399                 goto err;
 400
 401         /* tail entry */
 402         entry_return_size = sizeof(struct ipt_entry) +
 403                                 sizeof(struct ipt_standard_target);
 404         entry_return = g_try_malloc0(entry_return_size);
 405         if (entry_return == NULL)
 406                 goto err;
 407
 408         memset(entry_return, 0, entry_return_size);
 409
 410         entry_return->target_offset = sizeof(struct ipt_entry);
 411         entry_return->next_offset = entry_return_size;
 412
 413         standard = (struct ipt_standard_target *) entry_return->elems;
 414         standard->target.u.user.target_size =
 415                                 ALIGN(sizeof(struct ipt_standard_target));
 416         standard->verdict = XT_RETURN;
 417
 418         if (iptables_add_entry(table, entry_return, last, -1) < 0)
 419                 goto err;
 420
 421         return 0;
 422
 423 err:
 424         g_free(entry_head);
 425         g_free(entry_return);
 426
 427         return -ENOMEM;
 428 }
 429
 430 static struct ipt_entry *
 431 new_rule(struct connman_iptables *table, struct ipt_ip *ip,
 432                 char *target_name, struct xtables_target *xt_t,
 433                 char *match_name, struct xtables_match *xt_m)
 434 {
 435         struct ipt_entry *new_entry;
 436         size_t match_size, target_size;
 437         int is_builtin = is_builtin_target(target_name);
 438
 439         if (xt_m)
 440                 match_size = xt_m->m->u.match_size;
 441         else
 442                 match_size = 0;
 443
 444         if (xt_t)
 445                 target_size = ALIGN(xt_t->t->u.target_size);
 446         else
 447                 target_size = ALIGN(sizeof(struct xt_standard_target));
 448
 449         new_entry = g_try_malloc0(sizeof(struct ipt_entry) + target_size +
 450                                                                 match_size);
 451         if (new_entry == NULL)
 452                 return NULL;
 453
 454         memcpy(&new_entry->ip, ip, sizeof(struct ipt_ip));
 455
 456         new_entry->target_offset = sizeof(struct ipt_entry) + match_size;
 457         new_entry->next_offset = sizeof(struct ipt_entry) + target_size +
 458                                                                 match_size;
 459         if (xt_m) {
 460                 struct xt_entry_match *entry_match;
 461
 462                 entry_match = (struct xt_entry_match *)new_entry->elems;
 463                 memcpy(entry_match, xt_m->m, match_size);
 464         }
 465
 466         if (xt_t) {
 467                 struct xt_entry_target *entry_target;
 468
 469                 if (is_builtin) {
 470                         struct xt_standard_target *target;
 471
 472                         target = (struct xt_standard_target *)(xt_t->t);
 473                         strcpy(target->target.u.user.name, IPT_STANDARD_TARGET);
 474                         target->verdict = target_to_verdict(target_name);
 475                 }
 476
 477                 entry_target = ipt_get_target(new_entry);
 478                 memcpy(entry_target, xt_t->t, target_size);
 479         } else {
 480                 struct connman_iptables_entry *target_rule;
 481                 struct xt_standard_target *target;
 482                 GList *chain_head;
 483
 484                 /*
 485                  * This is a user defined target, i.e. a chain jump.
 486                  * We search for the chain head, and the target verdict
 487                  * is the first rule's offset on this chain.
 488                  * The offset is from the beginning of the table.
 489                  */
 490
 491                 chain_head = find_chain_head(table, target_name);
 492                 if (chain_head == NULL || chain_head->next == NULL) {
 493                         g_free(new_entry);
 494                         return NULL;
 495                 }
 496
 497                 target_rule = chain_head->next->data;
 498
 499                 target = (struct xt_standard_target *)ipt_get_target(new_entry);
 500                 strcpy(target->target.u.user.name, IPT_STANDARD_TARGET);
 501                 target->target.u.user.target_size = target_size;
 502                 target->verdict = target_rule->offset;
 503         }
 504
 505         return new_entry;
 506 }
 507
 508 static void update_hooks(struct connman_iptables *table, GList *chain_head,
 509                                 struct ipt_entry *entry)
 510 {
 511         GList *list;
 512         struct connman_iptables_entry *head, *e;
 513         int builtin;
 514
 515         if (chain_head == NULL)
 516                 return;
 517
 518         head = chain_head->data;
 519
 520         builtin = head->builtin;
 521         if (builtin < 0)
 522                 return;
 523
 524         table->underflow[builtin] += entry->next_offset;
 525
 526         for (list = chain_head->next; list; list = list->next) {
 527                 e = list->data;
 528
 529                 builtin = e->builtin;
 530                 if (builtin < 0)
 531                         continue;
 532
 533                 table->hook_entry[builtin] += entry->next_offset;
 534                 table->underflow[builtin] += entry->next_offset;
 535         }
 536 }
 537
 538 static int
 539 iptables_add_rule(struct connman_iptables *table,
 540                                 struct ipt_ip *ip, char *chain_name,
 541                                 char *target_name, struct xtables_target *xt_t,
 542                                 char *match_name, struct xtables_match *xt_m)
 543 {
 544         GList *chain_tail, *chain_head;
 545         struct ipt_entry *new_entry;
 546         struct connman_iptables_entry *head;
 547         int builtin = -1;
 548
 549         chain_tail = find_chain_tail(table, chain_name);
 550         if (chain_tail == NULL)
 551                 return -EINVAL;
 552
 553         chain_head = find_chain_head(table, chain_name);
 554         if (chain_head == NULL)
 555                 return -EINVAL;
 556
 557         new_entry = new_rule(table, ip,
 558                                 target_name, xt_t,
 559                                 match_name, xt_m);
 560         if (new_entry == NULL)
 561                 return -EINVAL;
 562
 563         update_hooks(table, chain_head, new_entry);
 564
 565         /*
 566          * If the chain is builtin, and does not have any rule,
 567          * then the one that we're inserting is becoming the head
 568          * and thus needs the builtin flag.
 569          */
 570         head = chain_head->data;
 571         if (head->builtin < 0)
 572                 builtin = -1;
 573         else if (chain_head == chain_tail->prev) {
 574                 head->builtin = -1;
 575                 builtin = head->builtin;
 576         }
 577
 578         return iptables_add_entry(table, new_entry, chain_tail->prev, builtin);
 579 }
 580
 581 static struct ipt_replace *
 582 iptables_blob(struct connman_iptables *table)
 583 {
 584         struct ipt_replace *r;
 585         GList *list;
 586         struct connman_iptables_entry *e;
 587         unsigned char *entry_index;
 588
 589         r = g_try_malloc0(sizeof(struct ipt_replace) + table->size);
 590         if (r == NULL)
 591                 return NULL;
 592
 593         memset(r, 0, sizeof(*r) + table->size);
 594
 595         r->counters = g_try_malloc0(sizeof(struct xt_counters)
 596                                 * table->num_entries);
 597         if (r->counters == NULL) {
 598                 g_free(r);
 599                 return NULL;
 600         }
 601
 602         strcpy(r->name, table->info->name);
 603         r->num_entries = table->num_entries;
 604         r->size = table->size;
 605
 606         r->num_counters = table->old_entries;
 607         r->valid_hooks  = table->info->valid_hooks;
 608
 609         memcpy(r->hook_entry, table->hook_entry, sizeof(table->hook_entry));
 610         memcpy(r->underflow, table->underflow, sizeof(table->underflow));
 611
 612         entry_index = (unsigned char *)r->entries;
 613         for (list = table->entries; list; list = list->next) {
 614                 e = list->data;
 615
 616                 memcpy(entry_index, e->entry, e->entry->next_offset);
 617                 entry_index += e->entry->next_offset;
 618         }
 619
 620         return r;
 621 }
 622
 623 static void dump_ip(struct ipt_entry *entry)
 624 {
 625         struct ipt_ip *ip = &entry->ip;
 626         char ip_string[INET6_ADDRSTRLEN];
 627         char ip_mask[INET6_ADDRSTRLEN];
 628
 629         if (strlen(ip->iniface))
 630                 connman_info("\tin %s", ip->iniface);
 631
 632         if (strlen(ip->outiface))
 633                 connman_info("\tout %s", ip->outiface);
 634
 635         if (inet_ntop(AF_INET, &ip->src, ip_string, INET6_ADDRSTRLEN) != NULL &&
 636                         inet_ntop(AF_INET, &ip->smsk,
 637                                         ip_mask, INET6_ADDRSTRLEN) != NULL)
 638                 connman_info("\tsrc %s/%s", ip_string, ip_mask);
 639
 640         if (inet_ntop(AF_INET, &ip->dst, ip_string, INET6_ADDRSTRLEN) != NULL &&
 641                         inet_ntop(AF_INET, &ip->dmsk,
 642                                         ip_mask, INET6_ADDRSTRLEN) != NULL)
 643                 connman_info("\tdst %s/%s", ip_string, ip_mask);
 644 }
 645
 646 static void dump_target(struct connman_iptables *table,
 647                                 struct ipt_entry *entry)
 648
 649 {
 650         struct xtables_target *xt_t;
 651         struct xt_entry_target *target;
 652
 653         target = ipt_get_target(entry);
 654
 655         if (!strcmp(target->u.user.name, IPT_STANDARD_TARGET)) {
 656                 struct xt_standard_target *t;
 657
 658                 t = (struct xt_standard_target *)target;
 659
 660                 switch (t->verdict) {
 661                 case XT_RETURN:
 662                         connman_info("\ttarget RETURN");
 663                         break;
 664
 665                 case -NF_ACCEPT - 1:
 666                         connman_info("\ttarget ACCEPT");
 667                         break;
 668
 669                 case -NF_DROP - 1:
 670                         connman_info("\ttarget DROP");
 671                         break;
 672
 673                 case -NF_QUEUE - 1:
 674                         connman_info("\ttarget QUEUE");
 675                         break;
 676
 677                 case -NF_STOP - 1:
 678                         connman_info("\ttarget STOP");
 679                         break;
 680
 681                 default:
 682                         connman_info("\tJUMP @%p (0x%x)",
 683                                 (char*)table->blob_entries->entrytable +
 684                                 t->verdict, t->verdict);
 685                         break;
 686                 }
 687
 688                 xt_t = xtables_find_target(IPT_STANDARD_TARGET,
 689                                                 XTF_LOAD_MUST_SUCCEED);
 690
 691                 if(xt_t->print != NULL)
 692                         xt_t->print(NULL, target, 1);
 693         } else {
 694                 xt_t = xtables_find_target(target->u.user.name, XTF_TRY_LOAD);
 695                 if (xt_t == NULL) {
 696                         connman_info("\ttarget %s", target->u.user.name);
 697                         return;
 698                 }
 699
 700                 if(xt_t->print != NULL) {
 701                         connman_info("\ttarget ");
 702                         xt_t->print(NULL, target, 1);
 703                 }
 704         }
 705 }
 706
 707 static void dump_match(struct connman_iptables *table, struct ipt_entry *entry)
 708 {
 709         struct xtables_match *xt_m;
 710         struct xt_entry_match *match;
 711
 712         if (entry->elems == (unsigned char *)entry + entry->target_offset)
 713                 return;
 714
 715         match = (struct xt_entry_match *) entry->elems;
 716
 717         if (!strlen(match->u.user.name))
 718                 return;
 719
 720         xt_m = xtables_find_match(match->u.user.name, XTF_TRY_LOAD, NULL);
 721         if (xt_m == NULL)
 722                 goto out;
 723
 724         if(xt_m->print != NULL) {
 725                 connman_info("\tmatch ");
 726                 xt_m->print(NULL, match, 1);
 727
 728                 return;
 729         }
 730
 731 out:
 732         connman_info("\tmatch %s", match->u.user.name);
 733
 734 }
 735
 736 static int dump_entry(struct ipt_entry *entry,
 737                                 struct connman_iptables *table)
 738 {
 739         struct xt_entry_target *target;
 740         unsigned int offset;
 741         int builtin;
 742
 743         offset = (char *)entry - (char *)table->blob_entries->entrytable;
 744         target = ipt_get_target(entry);
 745         builtin = is_hook_entry(table, entry);
 746
 747         if (entry_to_offset(table, entry) + entry->next_offset ==
 748                                         table->blob_entries->size) {
 749                 connman_info("End of CHAIN 0x%x", offset);
 750                 return 0;
 751         }
 752
 753         if (!strcmp(target->u.user.name, IPT_ERROR_TARGET)) {
 754                 connman_info("USER CHAIN (%s) %p  match %p  target %p  size %d",
 755                         target->data, entry, entry->elems,
 756                         (char *)entry + entry->target_offset,
 757                                 entry->next_offset);
 758
 759                 return 0;
 760         } else if (builtin >= 0) {
 761                 connman_info("CHAIN (%s) %p  match %p  target %p  size %d",
 762                         hooknames[builtin], entry, entry->elems,
 763                         (char *)entry + entry->target_offset,
 764                                 entry->next_offset);
 765         } else {
 766                 connman_info("RULE %p  match %p  target %p  size %d", entry,
 767                         entry->elems,
 768                         (char *)entry + entry->target_offset,
 769                                 entry->next_offset);
 770         }
 771
 772         dump_match(table, entry);
 773         dump_target(table, entry);
 774         dump_ip(entry);
 775
 776         return 0;
 777 }
 778
 779 static void iptables_dump(struct connman_iptables *table)
 780 {
 781         connman_info("%s valid_hooks=0x%08x, num_entries=%u, size=%u",
 782                         table->info->name,
 783                         table->info->valid_hooks, table->info->num_entries,
 784                                 table->info->size);
 785
 786         ENTRY_ITERATE(table->blob_entries->entrytable,
 787                         table->blob_entries->size,
 788                         dump_entry, table);
 789
 790 }
 791
 792 static int iptables_get_entries(struct connman_iptables *table)
 793 {
 794         socklen_t entry_size;
 795
 796         entry_size = sizeof(struct ipt_get_entries) + table->info->size;
 797
 798         return getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_ENTRIES,
 799                                 table->blob_entries, &entry_size);
 800 }
 801
 802 static int iptables_replace(struct connman_iptables *table,
 803                                         struct ipt_replace *r)
 804 {
 805         return setsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_SET_REPLACE, r,
 806                          sizeof(*r) + r->size);
 807 }
 808
 809 static int add_entry(struct ipt_entry *entry, struct connman_iptables *table)
 810 {
 811         struct ipt_entry *new_entry;
 812         int builtin;
 813
 814         new_entry = g_try_malloc0(entry->next_offset);
 815         if (new_entry == NULL)
 816                 return -ENOMEM;
 817
 818         memcpy(new_entry, entry, entry->next_offset);
 819
 820         builtin = is_hook_entry(table, entry);
 821
 822         return iptables_add_entry(table, new_entry, NULL, builtin);
 823 }
 824
 825 static void table_cleanup(struct connman_iptables *table)
 826 {
 827         GList *list;
 828         struct connman_iptables_entry *entry;
 829
 830         close(table->ipt_sock);
 831
 832         for (list = table->entries; list; list = list->next) {
 833                 entry = list->data;
 834
 835                 g_free(entry->entry);
 836         }
 837
 838         g_list_free(table->entries);
 839         g_free(table->info);
 840         g_free(table->blob_entries);
 841         g_free(table);
 842 }
 843
 844 static struct connman_iptables *iptables_init(char *table_name)
 845 {
 846         struct connman_iptables *table;
 847         socklen_t s;
 848
 849         table = g_hash_table_lookup(table_hash, table_name);
 850         if (table != NULL)
 851                 return table;
 852
 853         table = g_try_new0(struct connman_iptables, 1);
 854         if (table == NULL)
 855                 return NULL;
 856
 857         table->info = g_try_new0(struct ipt_getinfo, 1);
 858         if (table->info == NULL)
 859                 goto err;
 860
 861         table->ipt_sock = socket(AF_INET, SOCK_RAW, IPPROTO_RAW);
 862         if (table->ipt_sock < 0)
 863                 goto err;
 864
 865         s = sizeof(*table->info);
 866         strcpy(table->info->name, table_name);
 867         if (getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_INFO,
 868                                                 table->info, &s) < 0)
 869                 goto err;
 870
 871         table->blob_entries = g_try_malloc0(sizeof(struct ipt_get_entries) +
 872                                                 table->info->size);
 873         if (table->blob_entries == NULL)
 874                 goto err;
 875
 876         strcpy(table->blob_entries->name, table_name);
 877         table->blob_entries->size = table->info->size;
 878
 879         if (iptables_get_entries(table) < 0)
 880                 goto err;
 881
 882         table->num_entries = 0;
 883         table->old_entries = table->info->num_entries;
 884         table->size = 0;
 885
 886         memcpy(table->underflow, table->info->underflow,
 887                                 sizeof(table->info->underflow));
 888         memcpy(table->hook_entry, table->info->hook_entry,
 889                                 sizeof(table->info->hook_entry));
 890
 891         ENTRY_ITERATE(table->blob_entries->entrytable,
 892                         table->blob_entries->size,
 893                                 add_entry, table);
 894
 895         g_hash_table_insert(table_hash, table_name, table);
 896
 897         return table;
 898
 899 err:
 900
 901         table_cleanup(table);
 902
 903         return NULL;
 904 }
 905
 906 static struct option iptables_opts[] = {
 907         {.name = "append",        .has_arg = 1, .val = 'A'},
 908         {.name = "list",          .has_arg = 2, .val = 'L'},
 909         {.name = "new-chain",     .has_arg = 1, .val = 'N'},
 910         {.name = "destination",   .has_arg = 1, .val = 'd'},
 911         {.name = "in-interface",  .has_arg = 1, .val = 'i'},
 912         {.name = "jump",          .has_arg = 1, .val = 'j'},
 913         {.name = "match",         .has_arg = 1, .val = 'm'},
 914         {.name = "out-interface", .has_arg = 1, .val = 'o'},
 915         {.name = "source",        .has_arg = 1, .val = 's'},
 916         {.name = "table",         .has_arg = 1, .val = 't'},
 917         {NULL},
 918 };
 919
 920 struct xtables_globals iptables_globals = {
 921         .option_offset = 0,
 922         .opts = iptables_opts,
 923         .orig_opts = iptables_opts,
 924 };
 925
 926 static int iptables_command(int argc, char *argv[])
 927 {
 928         struct connman_iptables *table;
 929         struct xtables_match *xt_m;
 930         struct xtables_target *xt_t;
 931         struct ipt_ip ip;
 932         char *table_name, *chain, *new_chain, *match_name, *target_name;
 933         int c, ret, in_len, out_len;
 934         size_t size;
 935         gboolean dump, invert;
 936         struct in_addr src, dst;
 937
 938         if (argc == 0)
 939                 return -EINVAL;
 940
 941         dump = FALSE;
 942         invert = FALSE;
 943         table_name = chain = new_chain = match_name = target_name = NULL;
 944         memset(&ip, 0, sizeof(struct ipt_ip));
 945         table = NULL;
 946         xt_m = NULL;
 947         xt_t = NULL;
 948         ret = 0;
 949
 950         optind = 0;
 951
 952         while ((c = getopt_long(argc, argv,
 953            "-A:L::N:d:j:i:m:o:s:t:", iptables_globals.opts, NULL)) != -1) {
 954                 switch (c) {
 955                 case 'A':
 956                         chain = optarg;
 957                         break;
 958
 959                 case 'L':
 960                         dump = TRUE;
 961                         break;
 962
 963                 case 'N':
 964                         new_chain = optarg;
 965                         break;
 966
 967                 case 'd':
 968                         if (!inet_pton(AF_INET, optarg, &dst))
 969                                 break;
 970
 971                         ip.dst = dst;
 972                         inet_pton(AF_INET, "255.255.255.255", &ip.dmsk);
 973
 974                         if (invert)
 975                                 ip.invflags |= IPT_INV_DSTIP;
 976
 977                         break;
 978
 979                 case 'i':
 980                         in_len = strlen(optarg);
 981
 982                         if (in_len + 1 > IFNAMSIZ)
 983                                 break;
 984
 985                         strcpy(ip.iniface, optarg);
 986                         memset(ip.iniface_mask, 0xff, in_len + 1);
 987
 988                         if (invert)
 989                                 ip.invflags |= IPT_INV_VIA_IN;
 990
 991                         break;
 992
 993                 case 'j':
 994                         target_name = optarg;
 995                         xt_t = xtables_find_target(target_name, XTF_TRY_LOAD);
 996
 997                         if (xt_t == NULL)
 998                                 break;
 999
1000                         size = ALIGN(sizeof(struct ipt_entry_target)) +
1001                                                                 xt_t->size;
1002
1003                         xt_t->t = g_try_malloc0(size);
1004                         if (xt_t->t == NULL)
1005                                 goto out;
1006                         xt_t->t->u.target_size = size;
1007                         strcpy(xt_t->t->u.user.name, target_name);
1008                         xt_t->t->u.user.revision = xt_t->revision;
1009                         if (xt_t->init != NULL)
1010                                 xt_t->init(xt_t->t);
1011                         iptables_globals.opts =
1012                                 xtables_merge_options(iptables_globals.opts,
1013                                                      xt_t->extra_opts,
1014                                                      &xt_t->option_offset);
1015                         if (iptables_globals.opts == NULL)
1016                                 goto out;
1017
1018                         break;
1019
1020                 case 'm':
1021                         match_name = optarg;
1022
1023                         xt_m = xtables_find_match(optarg, XTF_LOAD_MUST_SUCCEED, NULL);
1024                         size = ALIGN(sizeof(struct ipt_entry_match)) +
1025                                                                 xt_m->size;
1026                         xt_m->m = g_try_malloc0(size);
1027                         if (xt_m == NULL)
1028                                 goto out;
1029                         xt_m->m->u.match_size = size;
1030                         strcpy(xt_m->m->u.user.name, xt_m->name);
1031                         xt_m->m->u.user.revision = xt_m->revision;
1032                         if (xt_m->init != NULL)
1033                                 xt_m->init(xt_m->m);
1034                         if (xt_m != xt_m->next) {
1035                                 iptables_globals.opts =
1036                                 xtables_merge_options(iptables_globals.opts,
1037                                                 xt_m->extra_opts,
1038                                                 &xt_m->option_offset);
1039                                 if (iptables_globals.opts == NULL)
1040                                         goto out;
1041                         }
1042
1043                         break;
1044
1045                 case 'o':
1046                         out_len = strlen(optarg);
1047
1048                         if (out_len + 1 > IFNAMSIZ)
1049                                 break;
1050
1051                         strcpy(ip.outiface, optarg);
1052                         memset(ip.outiface_mask, 0xff, out_len + 1);
1053
1054                         if (invert)
1055                                 ip.invflags |= IPT_INV_VIA_OUT;
1056
1057                         break;
1058
1059                 case 's':
1060                         if (!inet_pton(AF_INET, optarg, &src))
1061                                 break;
1062
1063                         ip.src = src;
1064                         inet_pton(AF_INET, "255.255.255.255", &ip.smsk);
1065
1066                         if (invert)
1067                                 ip.invflags |= IPT_INV_SRCIP;
1068
1069                         break;
1070
1071                 case 't':
1072                         table_name = optarg;
1073                         break;
1074
1075                 case 1:
1076                         if (optarg[0] == '!' && optarg[1] == '\0') {
1077                                 invert = TRUE;
1078                                 optarg[0] = '\0';
1079                                 continue;
1080                         }
1081
1082                         connman_error("Invalid option");
1083
1084                         ret = -EINVAL;
1085                         goto out;
1086
1087                 default:
1088                         if (xt_t == NULL || xt_t->parse == NULL ||
1089                             !xt_t->parse(c - xt_t->option_offset, argv, invert,
1090                                         &xt_t->tflags, NULL, &xt_t->t)) {
1091                                 if (xt_m == NULL || xt_m->parse == NULL)
1092                                         break;
1093
1094                                 xt_m->parse(c - xt_m->option_offset, argv,
1095                                         invert, &xt_m->mflags, NULL, &xt_m->m);
1096                         }
1097
1098                         break;
1099                 }
1100
1101                 invert = FALSE;
1102         }
1103
1104         if (table_name == NULL)
1105                 table_name = "filter";
1106
1107         table = iptables_init(table_name);
1108         if (table == NULL) {
1109                 ret = -EINVAL;
1110                 goto out;
1111         }
1112
1113         if (dump) {
1114                 iptables_dump(table);
1115
1116                 ret = 0;
1117                 goto out;
1118         }
1119
1120         if (chain && new_chain) {
1121                 ret = -EINVAL;
1122                 goto out;
1123         }
1124
1125         if (new_chain) {
1126                 DBG("New chain %s", new_chain);
1127
1128                 ret = iptables_add_chain(table, new_chain);
1129                 goto out;
1130         }
1131
1132         if (chain) {
1133                 if (target_name == NULL)
1134                         return -1;
1135
1136                 DBG("Adding %s to %s (match %s)",
1137                                 target_name, chain, match_name);
1138
1139                 ret = iptables_add_rule(table, &ip, chain, target_name, xt_t,
1140                                         match_name, xt_m);
1141
1142                 goto out;
1143         }
1144
1145 out:
1146         if (xt_t)
1147                 g_free(xt_t->t);
1148
1149         if (xt_m)
1150                 g_free(xt_m->m);
1151
1152         return ret;
1153 }
1154
1155 int __connman_iptables_command(const char *format, ...)
1156 {
1157         char **argv, **arguments, *command;
1158         int argc, i, ret;
1159         va_list args;
1160
1161         if (format == NULL)
1162                 return -EINVAL;
1163
1164         va_start(args, format);
1165
1166         command = g_strdup_vprintf(format, args);
1167
1168         va_end(args);
1169
1170         if (command == NULL)
1171                 return -ENOMEM;
1172
1173         arguments = g_strsplit_set(command, " ", -1);
1174
1175         for (argc = 0; arguments[argc]; argc++);
1176
1177         DBG("command %s argc %d", command, ++argc);
1178
1179         argv = g_try_malloc0(argc * sizeof(char *));
1180         if (argv == NULL) {
1181                 g_free(command);
1182                 g_strfreev(arguments);
1183                 return -ENOMEM;
1184         }
1185
1186         argv[0] = "iptables";
1187         for (i = 1; i < argc; i++)
1188                 argv[i] = arguments[i - 1];
1189
1190         ret = iptables_command(argc, argv);
1191
1192         g_free(command);
1193         g_strfreev(arguments);
1194         g_free(argv);
1195
1196         return ret;
1197 }
1198
1199
1200 int __connman_iptables_commit(const char *table_name)
1201 {
1202         struct connman_iptables *table;
1203         struct ipt_replace *repl;
1204
1205         table = g_hash_table_lookup(table_hash, table_name);
1206         if (table == NULL)
1207                 return -EINVAL;
1208
1209         repl = iptables_blob(table);
1210
1211         return iptables_replace(table, repl);
1212 }
1213
1214 static void remove_table(gpointer user_data)
1215 {
1216         struct connman_iptables *table = user_data;
1217
1218         table_cleanup(table);
1219 }
1220
1221 int __connman_iptables_init(void)
1222 {
1223         DBG("");
1224
1225         table_hash = g_hash_table_new_full(g_str_hash, g_str_equal,
1226                                                 NULL, remove_table);
1227
1228         xtables_init_all(&iptables_globals, NFPROTO_IPV4);
1229
1230         return 0;
1231
1232 }
1233
1234 void __connman_iptables_cleanup(void)
1235 {
1236         g_hash_table_destroy(table_hash);
1237
1238         xtables_free_opts(1);
1239 }