/* * * Connection Manager * * Copyright (C) 2007-2012 Intel Corporation. All rights reserved. * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License version 2 as * published by the Free Software Foundation. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA * */ #ifdef HAVE_CONFIG_H #include #endif #include #include #include #include #include #include #include #include #include #include "connman.h" void flush_table(const char *name); /* * Some comments on how the iptables API works (some of them from the * source code from iptables and the kernel): * * - valid_hooks: bit indicates valid IDs for hook_entry * - hook_entry[ID] offset to the chain start * - overflows should be end of entry chains, and uncodintional policy nodes. * - policy entry: last entry in a chain * - user chain: end of last builtin + policy entry * - final entry must be error node * - Underflows must be unconditional and use the STANDARD target with * ACCEPT/DROP * - IPT_SO_GET_INFO and IPT_SO_GET_ENTRIES are used to read a table * - IPT_SO_GET_INFO: struct ipt_getinfo (note the lack of table content) * - IPT_SO_GET_ENTRIES: struct ipt_get_entries (contains only parts of the * table header/meta info. The table is appended after the header. The entries * are of the type struct ipt_entry. * - After the ipt_entry the matches are appended. After the matches * the target is appended. * - ipt_entry->target_offset = Size of ipt_entry + matches * - ipt_entry->next_offset = Size of ipt_entry + matches + target * - IPT_SO_SET_REPLACE is used to write a table (contains the complete * - hook_entry and overflow mark the begining and the end of a chain, e.g * entry hook: pre/in/fwd/out/post -1/0/352/504/-1 * underflow: pre/in/fwd/out/post -1/200/352/904/-1 * means that INPUT starts at offset 0 and ends at 200 (the start offset to * the last element). FORWARD has one entry starting/ending at 352. The entry * has a size of 152. 352 + 152 = 504 which is the start of the OUTPUT chain * which then ends at 904. PREROUTING and POSTROUTING are invalid hooks in * the filter table. * - 'iptables -t filter -A INPUT -m mark --mark 999 -j LOG' * writing that table looks like this: * * filter valid_hooks 0x0000000e num_entries 5 size 856 * entry hook: pre/in/fwd/out/post -1/0/376/528/-1 * underflow: pre/in/fwd/out/post -1/224/376/528/-1 * entry 0x699d30 offset 0 size 224 * RULE match 0x699da0 target 0x699dd0 * match mark match 0x3e7 * target LOG flags 0 level 4 * src 0.0.0.0/0.0.0.0 * dst 0.0.0.0/0.0.0.0 * entry 0x699e10 offset 224 size 152 * RULE match 0x699e80 target 0x699e80 * target ACCEPT * src 0.0.0.0/0.0.0.0 * dst 0.0.0.0/0.0.0.0 * entry 0x699ea8 offset 376 size 152 * RULE match 0x699f18 target 0x699f18 * target ACCEPT * src 0.0.0.0/0.0.0.0 * dst 0.0.0.0/0.0.0.0 * entry 0x699f40 offset 528 size 152 * RULE match 0x699fb0 target 0x699fb0 * target ACCEPT * src 0.0.0.0/0.0.0.0 * dst 0.0.0.0/0.0.0.0 * entry 0x699fd8 offset 680 size 176 * USER CHAIN (ERROR) match 0x69a048 target 0x69a048 * * Reading the filter table looks like this: * * filter valid_hooks 0x0000000e num_entries 5 size 856 * entry hook: pre/in/fwd/out/post -1/0/376/528/-1 * underflow: pre/in/fwd/out/post -1/224/376/528/-1 * entry 0x25fec28 offset 0 size 224 * CHAIN (INPUT) match 0x25fec98 target 0x25fecc8 * match mark match 0x3e7 * target LOG flags 0 level 4 * src 0.0.0.0/0.0.0.0 * dst 0.0.0.0/0.0.0.0 * entry 0x25fed08 offset 224 size 152 * RULE match 0x25fed78 target 0x25fed78 * target ACCEPT * src 0.0.0.0/0.0.0.0 * dst 0.0.0.0/0.0.0.0 * entry 0x25feda0 offset 376 size 152 * CHAIN (FORWARD) match 0x25fee10 target 0x25fee10 * target ACCEPT * src 0.0.0.0/0.0.0.0 * dst 0.0.0.0/0.0.0.0 * entry 0x25fee38 offset 528 size 152 * CHAIN (OUTPUT) match 0x25feea8 target 0x25feea8 * target ACCEPT * src 0.0.0.0/0.0.0.0 * dst 0.0.0.0/0.0.0.0 * entry 0x25feed0 offset 680 size 176 * End of CHAIN */ static const char *hooknames[] = { [NF_IP_PRE_ROUTING] = "PREROUTING", [NF_IP_LOCAL_IN] = "INPUT", [NF_IP_FORWARD] = "FORWARD", [NF_IP_LOCAL_OUT] = "OUTPUT", [NF_IP_POST_ROUTING] = "POSTROUTING", }; #define LABEL_ACCEPT "ACCEPT" #define LABEL_DROP "DROP" #define LABEL_QUEUE "QUEUE" #define LABEL_RETURN "RETURN" #define XT_OPTION_OFFSET_SCALE 256 #define MIN_ALIGN (__alignof__(struct ipt_entry)) #define ALIGN(s) (((s) + ((MIN_ALIGN)-1)) & ~((MIN_ALIGN)-1)) struct error_target { struct xt_entry_target t; char error[IPT_TABLE_MAXNAMELEN]; }; struct connman_iptables_entry { int offset; int builtin; struct ipt_entry *entry; }; struct connman_iptables { int ipt_sock; struct ipt_getinfo *info; struct ipt_get_entries *blob_entries; unsigned int num_entries; unsigned int old_entries; unsigned int size; unsigned int underflow[NF_INET_NUMHOOKS]; unsigned int hook_entry[NF_INET_NUMHOOKS]; GList *entries; }; static GHashTable *table_hash = NULL; static gboolean debug_enabled = FALSE; typedef int (*iterate_entries_cb_t)(struct ipt_entry *entry, int builtin, unsigned int hook,size_t size, unsigned int offset, void *user_data); static unsigned int next_hook_entry_index(unsigned int *valid_hooks) { unsigned int h; if (*valid_hooks == 0) return NF_INET_NUMHOOKS; h = __builtin_ffs(*valid_hooks) - 1; *valid_hooks ^= (1 << h); return h; } static int iterate_entries(struct ipt_entry *entries, unsigned int valid_hooks, unsigned int *hook_entry, unsigned int *underflow, size_t size, iterate_entries_cb_t cb, void *user_data) { unsigned int offset, h, hook; int builtin, err; struct ipt_entry *entry; h = next_hook_entry_index(&valid_hooks); hook = h; for (offset = 0, entry = entries; offset < size; offset += entry->next_offset) { builtin = -1; entry = (void *)entries + offset; /* * Updating builtin, hook and h is very tricky. * The rules are: * - builtin is only set to the current hook number * if the current entry is the hook entry (aka chain * head). And only for builtin chains, never for * the user chains. * - hook is the current hook number. If we * look at user chains it needs to be NF_INET_NETNUMHOOKS. * - h is the next hook entry. Thous we need to be carefully * not to access the table when h is NF_INET_NETNUMHOOKS. */ if (h < NF_INET_NUMHOOKS && hook_entry[h] == offset) { builtin = h; hook = h; } if (h == NF_INET_NUMHOOKS) hook = h; if (h < NF_INET_NUMHOOKS && underflow[h] <= offset) { h = next_hook_entry_index(&valid_hooks); } err = cb(entry, builtin, hook, size, offset, user_data); if (err < 0) return err; } return 0; } static int print_entry(struct ipt_entry *entry, int builtin, unsigned int hook, size_t size, unsigned int offset, void *user_data) { iterate_entries_cb_t cb = user_data; DBG("entry %p hook %d offset %d size %d", entry, hook, offset, entry->next_offset); return cb(entry, builtin, hook, size, offset, NULL); } static int target_to_verdict(const char *target_name) { if (!strcmp(target_name, LABEL_ACCEPT)) return -NF_ACCEPT - 1; if (!strcmp(target_name, LABEL_DROP)) return -NF_DROP - 1; if (!strcmp(target_name, LABEL_QUEUE)) return -NF_QUEUE - 1; if (!strcmp(target_name, LABEL_RETURN)) return XT_RETURN; return 0; } static gboolean is_builtin_target(const char *target_name) { if (!strcmp(target_name, LABEL_ACCEPT) || !strcmp(target_name, LABEL_DROP) || !strcmp(target_name, LABEL_QUEUE) || !strcmp(target_name, LABEL_RETURN)) return TRUE; return FALSE; } static gboolean is_jump(struct connman_iptables_entry *e) { struct xt_entry_target *target; target = ipt_get_target(e->entry); if (!strcmp(target->u.user.name, IPT_STANDARD_TARGET)) { struct xt_standard_target *t; t = (struct xt_standard_target *)target; switch (t->verdict) { case XT_RETURN: case -NF_ACCEPT - 1: case -NF_DROP - 1: case -NF_QUEUE - 1: case -NF_STOP - 1: return false; default: return true; } } return false; } static gboolean is_fallthrough(struct connman_iptables_entry *e) { struct xt_entry_target *target; target = ipt_get_target(e->entry); if (!g_strcmp0(target->u.user.name, IPT_STANDARD_TARGET)) { struct xt_standard_target *t; t = (struct xt_standard_target *)target; if (t->verdict == 0) return true; } return false; } static gboolean is_chain(struct connman_iptables *table, struct connman_iptables_entry *e) { struct ipt_entry *entry; struct xt_entry_target *target; entry = e->entry; if (e->builtin >= 0) return TRUE; target = ipt_get_target(entry); if (!strcmp(target->u.user.name, IPT_ERROR_TARGET)) return TRUE; return FALSE; } static GList *find_chain_head(struct connman_iptables *table, const char *chain_name) { GList *list; struct connman_iptables_entry *head; struct ipt_entry *entry; struct xt_entry_target *target; int builtin; for (list = table->entries; list; list = list->next) { head = list->data; entry = head->entry; /* Buit-in chain */ builtin = head->builtin; if (builtin >= 0 && !strcmp(hooknames[builtin], chain_name)) break; /* User defined chain */ target = ipt_get_target(entry); if (!strcmp(target->u.user.name, IPT_ERROR_TARGET) && !strcmp((char *)target->data, chain_name)) break; } return list; } static GList *find_chain_tail(struct connman_iptables *table, const char *chain_name) { struct connman_iptables_entry *tail; GList *chain_head, *list; chain_head = find_chain_head(table, chain_name); if (chain_head == NULL) return NULL; /* Then we look for the next chain */ for (list = chain_head->next; list; list = list->next) { tail = list->data; if (is_chain(table, tail)) return list; } /* Nothing found, we return the table end */ return g_list_last(table->entries); } static void update_offsets(struct connman_iptables *table) { GList *list, *prev; struct connman_iptables_entry *entry, *prev_entry; for (list = table->entries; list; list = list->next) { entry = list->data; if (list == table->entries) { entry->offset = 0; continue; } prev = list->prev; prev_entry = prev->data; entry->offset = prev_entry->offset + prev_entry->entry->next_offset; } } static void update_targets_reference(struct connman_iptables *table, struct connman_iptables_entry *entry_before, struct connman_iptables_entry *modified_entry, gboolean is_removing) { struct connman_iptables_entry *tmp; struct xt_standard_target *t; GList *list; int offset; offset = modified_entry->entry->next_offset; for (list = table->entries; list; list = list->next) { tmp = list->data; if (!is_jump(tmp)) continue; t = (struct xt_standard_target *)ipt_get_target(tmp->entry); if (is_removing == TRUE) { if (t->verdict >= entry_before->offset) t->verdict -= offset; } else { if (t->verdict > entry_before->offset) t->verdict += offset; } } if (is_fallthrough(modified_entry)) { t = (struct xt_standard_target *) ipt_get_target(modified_entry->entry); t->verdict = entry_before->offset + modified_entry->entry->target_offset + ALIGN(sizeof(struct xt_standard_target)); t->target.u.target_size = ALIGN(sizeof(struct xt_standard_target)); } } static int iptables_add_entry(struct connman_iptables *table, struct ipt_entry *entry, GList *before, int builtin) { struct connman_iptables_entry *e, *entry_before; if (table == NULL) return -1; e = g_try_malloc0(sizeof(struct connman_iptables_entry)); if (e == NULL) return -1; e->entry = entry; e->builtin = builtin; table->entries = g_list_insert_before(table->entries, before, e); table->num_entries++; table->size += entry->next_offset; if (before == NULL) { e->offset = table->size - entry->next_offset; return 0; } entry_before = before->data; /* * We've just appended/insterted a new entry. All references * should be bumped accordingly. */ update_targets_reference(table, entry_before, e, FALSE); update_offsets(table); return 0; } static int remove_table_entry(struct connman_iptables *table, struct connman_iptables_entry *entry) { int removed = 0; table->num_entries--; table->size -= entry->entry->next_offset; removed = entry->entry->next_offset; table->entries = g_list_remove(table->entries, entry); g_free(entry->entry); g_free(entry); return removed; } static int iptables_flush_chain(struct connman_iptables *table, const char *name) { GList *chain_head, *chain_tail, *list, *next; struct connman_iptables_entry *entry; int builtin, removed = 0; chain_head = find_chain_head(table, name); if (chain_head == NULL) return -EINVAL; chain_tail = find_chain_tail(table, name); if (chain_tail == NULL) return -EINVAL; entry = chain_head->data; builtin = entry->builtin; if (builtin >= 0) list = chain_head; else list = chain_head->next; if (list == chain_tail->prev) return 0; while (list != chain_tail->prev) { entry = list->data; next = g_list_next(list); removed += remove_table_entry(table, entry); list = next; } if (builtin >= 0) { struct connman_iptables_entry *e; entry = list->data; entry->builtin = builtin; table->underflow[builtin] -= removed; for (list = chain_tail; list; list = list->next) { e = list->data; builtin = e->builtin; if (builtin < 0) continue; table->hook_entry[builtin] -= removed; table->underflow[builtin] -= removed; } } update_offsets(table); return 0; } static int iptables_add_chain(struct connman_iptables *table, const char *name) { GList *last; struct ipt_entry *entry_head; struct ipt_entry *entry_return; struct error_target *error; struct ipt_standard_target *standard; u_int16_t entry_head_size, entry_return_size; last = g_list_last(table->entries); /* * An empty chain is composed of: * - A head entry, with no match and an error target. * The error target data is the chain name. * - A tail entry, with no match and a standard target. * The standard target verdict is XT_RETURN (return to the * caller). */ /* head entry */ entry_head_size = sizeof(struct ipt_entry) + sizeof(struct error_target); entry_head = g_try_malloc0(entry_head_size); if (entry_head == NULL) goto err_head; memset(entry_head, 0, entry_head_size); entry_head->target_offset = sizeof(struct ipt_entry); entry_head->next_offset = entry_head_size; error = (struct error_target *) entry_head->elems; strcpy(error->t.u.user.name, IPT_ERROR_TARGET); error->t.u.user.target_size = ALIGN(sizeof(struct error_target)); strcpy(error->error, name); if (iptables_add_entry(table, entry_head, last, -1) < 0) goto err_head; /* tail entry */ entry_return_size = sizeof(struct ipt_entry) + sizeof(struct ipt_standard_target); entry_return = g_try_malloc0(entry_return_size); if (entry_return == NULL) goto err; memset(entry_return, 0, entry_return_size); entry_return->target_offset = sizeof(struct ipt_entry); entry_return->next_offset = entry_return_size; standard = (struct ipt_standard_target *) entry_return->elems; standard->target.u.user.target_size = ALIGN(sizeof(struct ipt_standard_target)); standard->verdict = XT_RETURN; if (iptables_add_entry(table, entry_return, last, -1) < 0) goto err; return 0; err: g_free(entry_return); err_head: g_free(entry_head); return -ENOMEM; } static int iptables_delete_chain(struct connman_iptables *table, const char *name) { struct connman_iptables_entry *entry; GList *chain_head, *chain_tail; chain_head = find_chain_head(table, name); if (chain_head == NULL) return -EINVAL; entry = chain_head->data; /* We cannot remove builtin chain */ if (entry->builtin >= 0) return -EINVAL; chain_tail = find_chain_tail(table, name); if (chain_tail == NULL) return -EINVAL; /* Chain must be flushed */ if (chain_head->next != chain_tail->prev) return -EINVAL; remove_table_entry(table, entry); entry = chain_tail->prev->data; remove_table_entry(table, entry); update_offsets(table); return 0; } static struct ipt_entry *new_rule(struct ipt_ip *ip, const char *target_name, struct xtables_target *xt_t, struct xtables_rule_match *xt_rm) { struct xtables_rule_match *tmp_xt_rm; struct ipt_entry *new_entry; size_t match_size, target_size; match_size = 0; for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL; tmp_xt_rm = tmp_xt_rm->next) match_size += tmp_xt_rm->match->m->u.match_size; if (xt_t) target_size = ALIGN(xt_t->t->u.target_size); else target_size = ALIGN(sizeof(struct xt_standard_target)); new_entry = g_try_malloc0(sizeof(struct ipt_entry) + target_size + match_size); if (new_entry == NULL) return NULL; memcpy(&new_entry->ip, ip, sizeof(struct ipt_ip)); new_entry->target_offset = sizeof(struct ipt_entry) + match_size; new_entry->next_offset = sizeof(struct ipt_entry) + target_size + match_size; match_size = 0; for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL; tmp_xt_rm = tmp_xt_rm->next) { memcpy(new_entry->elems + match_size, tmp_xt_rm->match->m, tmp_xt_rm->match->m->u.match_size); match_size += tmp_xt_rm->match->m->u.match_size; } if (xt_t) { struct xt_entry_target *entry_target; entry_target = ipt_get_target(new_entry); memcpy(entry_target, xt_t->t, target_size); } return new_entry; } static void update_hooks(struct connman_iptables *table, GList *chain_head, struct ipt_entry *entry) { GList *list; struct connman_iptables_entry *head, *e; int builtin; if (chain_head == NULL) return; head = chain_head->data; builtin = head->builtin; if (builtin < 0) return; table->underflow[builtin] += entry->next_offset; for (list = chain_head->next; list; list = list->next) { e = list->data; builtin = e->builtin; if (builtin < 0) continue; table->hook_entry[builtin] += entry->next_offset; table->underflow[builtin] += entry->next_offset; } } static struct ipt_entry *prepare_rule_inclusion(struct connman_iptables *table, struct ipt_ip *ip, const char *chain_name, const char *target_name, struct xtables_target *xt_t, int *builtin, struct xtables_rule_match *xt_rm) { GList *chain_tail, *chain_head; struct ipt_entry *new_entry; struct connman_iptables_entry *head; chain_head = find_chain_head(table, chain_name); if (chain_head == NULL) return NULL; chain_tail = find_chain_tail(table, chain_name); if (chain_tail == NULL) return NULL; new_entry = new_rule(ip, target_name, xt_t, xt_rm); if (new_entry == NULL) return NULL; update_hooks(table, chain_head, new_entry); /* * If the chain is builtin, and does not have any rule, * then the one that we're inserting is becoming the head * and thus needs the builtin flag. */ head = chain_head->data; if (head->builtin < 0) *builtin = -1; else if (chain_head == chain_tail->prev) { *builtin = head->builtin; head->builtin = -1; } return new_entry; } static int iptables_insert_rule(struct connman_iptables *table, struct ipt_ip *ip, const char *chain_name, const char *target_name, struct xtables_target *xt_t, struct xtables_rule_match *xt_rm) { struct ipt_entry *new_entry; int builtin = -1, ret; GList *chain_head; chain_head = find_chain_head(table, chain_name); if (chain_head == NULL) return -EINVAL; new_entry = prepare_rule_inclusion(table, ip, chain_name, target_name, xt_t, &builtin, xt_rm); if (new_entry == NULL) return -EINVAL; if (builtin == -1) chain_head = chain_head->next; ret = iptables_add_entry(table, new_entry, chain_head, builtin); if (ret < 0) g_free(new_entry); return ret; } static gboolean is_same_ipt_entry(struct ipt_entry *i_e1, struct ipt_entry *i_e2) { if (memcmp(&i_e1->ip, &i_e2->ip, sizeof(struct ipt_ip)) != 0) return FALSE; if (i_e1->target_offset != i_e2->target_offset) return FALSE; if (i_e1->next_offset != i_e2->next_offset) return FALSE; return TRUE; } static gboolean is_same_target(struct xt_entry_target *xt_e_t1, struct xt_entry_target *xt_e_t2) { unsigned int i; if (xt_e_t1 == NULL || xt_e_t2 == NULL) return FALSE; if (strcmp(xt_e_t1->u.user.name, "") == 0 && strcmp(xt_e_t2->u.user.name, "") == 0) { /* fallthrough */ return TRUE; } else if (strcmp(xt_e_t1->u.user.name, IPT_STANDARD_TARGET) == 0) { struct xt_standard_target *xt_s_t1; struct xt_standard_target *xt_s_t2; xt_s_t1 = (struct xt_standard_target *) xt_e_t1; xt_s_t2 = (struct xt_standard_target *) xt_e_t2; if (xt_s_t1->verdict != xt_s_t2->verdict) return FALSE; } else { if (xt_e_t1->u.target_size != xt_e_t2->u.target_size) return FALSE; if (strcmp(xt_e_t1->u.user.name, xt_e_t2->u.user.name) != 0) return FALSE; for (i = 0; i < xt_e_t1->u.target_size - sizeof(struct xt_standard_target); i++) { if ((xt_e_t1->data[i] ^ xt_e_t2->data[i]) != 0) return FALSE; } } return TRUE; } static gboolean is_same_match(struct xt_entry_match *xt_e_m1, struct xt_entry_match *xt_e_m2) { unsigned int i; if (xt_e_m1 == NULL || xt_e_m2 == NULL) return FALSE; if (xt_e_m1->u.match_size != xt_e_m2->u.match_size) return FALSE; if (xt_e_m1->u.user.revision != xt_e_m2->u.user.revision) return FALSE; if (strcmp(xt_e_m1->u.user.name, xt_e_m2->u.user.name) != 0) return FALSE; for (i = 0; i < xt_e_m1->u.match_size - sizeof(struct xt_entry_match); i++) { if ((xt_e_m1->data[i] ^ xt_e_m2->data[i]) != 0) return FALSE; } return TRUE; } static GList *find_existing_rule(struct connman_iptables *table, struct ipt_ip *ip, const char *chain_name, const char *target_name, struct xtables_target *xt_t, struct xtables_match *xt_m, struct xtables_rule_match *xt_rm) { GList *chain_tail, *chain_head, *list; struct xt_entry_target *xt_e_t = NULL; struct xt_entry_match *xt_e_m = NULL; struct connman_iptables_entry *entry; struct ipt_entry *entry_test; int builtin; chain_head = find_chain_head(table, chain_name); if (chain_head == NULL) return NULL; chain_tail = find_chain_tail(table, chain_name); if (chain_tail == NULL) return NULL; if (!xt_t && !xt_m) return NULL; entry_test = new_rule(ip, target_name, xt_t, xt_rm); if (entry_test == NULL) return NULL; if (xt_t != NULL) xt_e_t = ipt_get_target(entry_test); if (xt_m != NULL) xt_e_m = (struct xt_entry_match *)entry_test->elems; entry = chain_head->data; builtin = entry->builtin; if (builtin >= 0) list = chain_head; else list = chain_head->next; for (; list != chain_tail->prev; list = list->next) { struct connman_iptables_entry *tmp; struct ipt_entry *tmp_e; tmp = list->data; tmp_e = tmp->entry; if (is_same_ipt_entry(entry_test, tmp_e) == FALSE) continue; if (xt_t != NULL) { struct xt_entry_target *tmp_xt_e_t; tmp_xt_e_t = ipt_get_target(tmp_e); if (!is_same_target(tmp_xt_e_t, xt_e_t)) continue; } if (xt_m != NULL) { struct xt_entry_match *tmp_xt_e_m; tmp_xt_e_m = (struct xt_entry_match *)tmp_e->elems; if (!is_same_match(tmp_xt_e_m, xt_e_m)) continue; } break; } g_free(entry_test); if (list != chain_tail->prev) return list; return NULL; } static int iptables_delete_rule(struct connman_iptables *table, struct ipt_ip *ip, const char *chain_name, const char *target_name, struct xtables_target *xt_t, struct xtables_match *xt_m, struct xtables_rule_match *xt_rm) { struct connman_iptables_entry *entry; GList *chain_head, *chain_tail, *list; int builtin, removed; removed = 0; chain_head = find_chain_head(table, chain_name); if (chain_head == NULL) return -EINVAL; chain_tail = find_chain_tail(table, chain_name); if (chain_tail == NULL) return -EINVAL; list = find_existing_rule(table, ip, chain_name, target_name, xt_t, xt_m, xt_rm); if (list == NULL) return -EINVAL; entry = chain_head->data; builtin = entry->builtin; entry = list->data; if (entry == NULL) return -EINVAL; /* We have deleted a rule, * all references should be bumped accordingly */ if (list->next != NULL) update_targets_reference(table, list->next->data, list->data, TRUE); removed += remove_table_entry(table, entry); if (builtin >= 0) { list = list->next; if (list) { entry = list->data; entry->builtin = builtin; } table->underflow[builtin] -= removed; for (list = chain_tail; list; list = list->next) { entry = list->data; builtin = entry->builtin; if (builtin < 0) continue; table->hook_entry[builtin] -= removed; table->underflow[builtin] -= removed; } } update_offsets(table); return 0; } static int iptables_change_policy(struct connman_iptables *table, const char *chain_name, const char *policy) { GList *chain_head; struct connman_iptables_entry *entry; struct xt_entry_target *target; struct xt_standard_target *t; int verdict; verdict = target_to_verdict(policy); if (verdict == 0) return -EINVAL; chain_head = find_chain_head(table, chain_name); if (chain_head == NULL) return -EINVAL; entry = chain_head->data; if (entry->builtin < 0) return -EINVAL; target = ipt_get_target(entry->entry); t = (struct xt_standard_target *)target; t->verdict = verdict; return 0; } static struct ipt_replace *iptables_blob(struct connman_iptables *table) { struct ipt_replace *r; GList *list; struct connman_iptables_entry *e; unsigned char *entry_index; r = g_try_malloc0(sizeof(struct ipt_replace) + table->size); if (r == NULL) return NULL; memset(r, 0, sizeof(*r) + table->size); r->counters = g_try_malloc0(sizeof(struct xt_counters) * table->old_entries); if (r->counters == NULL) { g_free(r); return NULL; } strcpy(r->name, table->info->name); r->num_entries = table->num_entries; r->size = table->size; r->num_counters = table->old_entries; r->valid_hooks = table->info->valid_hooks; memcpy(r->hook_entry, table->hook_entry, sizeof(table->hook_entry)); memcpy(r->underflow, table->underflow, sizeof(table->underflow)); entry_index = (unsigned char *)r->entries; for (list = table->entries; list; list = list->next) { e = list->data; memcpy(entry_index, e->entry, e->entry->next_offset); entry_index += e->entry->next_offset; } return r; } static void dump_ip(struct ipt_entry *entry) { struct ipt_ip *ip = &entry->ip; char ip_string[INET6_ADDRSTRLEN]; char ip_mask[INET6_ADDRSTRLEN]; if (strlen(ip->iniface)) DBG("\tin %s", ip->iniface); if (strlen(ip->outiface)) DBG("\tout %s", ip->outiface); if (inet_ntop(AF_INET, &ip->src, ip_string, INET6_ADDRSTRLEN) != NULL && inet_ntop(AF_INET, &ip->smsk, ip_mask, INET6_ADDRSTRLEN) != NULL) DBG("\tsrc %s/%s", ip_string, ip_mask); if (inet_ntop(AF_INET, &ip->dst, ip_string, INET6_ADDRSTRLEN) != NULL && inet_ntop(AF_INET, &ip->dmsk, ip_mask, INET6_ADDRSTRLEN) != NULL) DBG("\tdst %s/%s", ip_string, ip_mask); } static void dump_target(struct ipt_entry *entry) { struct xtables_target *xt_t; struct xt_entry_target *target; target = ipt_get_target(entry); if (!strcmp(target->u.user.name, IPT_STANDARD_TARGET)) { struct xt_standard_target *t; t = (struct xt_standard_target *)target; switch (t->verdict) { case XT_RETURN: DBG("\ttarget RETURN"); break; case -NF_ACCEPT - 1: DBG("\ttarget ACCEPT"); break; case -NF_DROP - 1: DBG("\ttarget DROP"); break; case -NF_QUEUE - 1: DBG("\ttarget QUEUE"); break; case -NF_STOP - 1: DBG("\ttarget STOP"); break; default: DBG("\tJUMP %u", t->verdict); break; } xt_t = xtables_find_target(IPT_STANDARD_TARGET, XTF_LOAD_MUST_SUCCEED); if(xt_t->print != NULL) xt_t->print(NULL, target, 1); } else { xt_t = xtables_find_target(target->u.user.name, XTF_TRY_LOAD); if (xt_t == NULL) { DBG("\ttarget %s", target->u.user.name); return; } if(xt_t->print != NULL) { DBG("\ttarget "); xt_t->print(NULL, target, 1); } } } static void dump_match(struct ipt_entry *entry) { struct xtables_match *xt_m; struct xt_entry_match *match; if (entry->elems == (unsigned char *)entry + entry->target_offset) return; match = (struct xt_entry_match *) entry->elems; if (!strlen(match->u.user.name)) return; xt_m = xtables_find_match(match->u.user.name, XTF_TRY_LOAD, NULL); if (xt_m == NULL) goto out; if(xt_m->print != NULL) { DBG("\tmatch "); xt_m->print(NULL, match, 1); return; } out: DBG("\tmatch %s", match->u.user.name); } static int dump_entry(struct ipt_entry *entry, int builtin, unsigned int hook, size_t size, unsigned int offset, void *user_data) { struct xt_entry_target *target; target = ipt_get_target(entry); if (offset + entry->next_offset == size) { DBG("\tEnd of CHAIN"); return 0; } if (!strcmp(target->u.user.name, IPT_ERROR_TARGET)) { DBG("\tUSER CHAIN (%s) match %p target %p", target->data, entry->elems, (char *)entry + entry->target_offset); return 0; } else if (builtin >= 0) { DBG("\tCHAIN (%s) match %p target %p", hooknames[builtin], entry->elems, (char *)entry + entry->target_offset); } else { DBG("\tRULE match %p target %p", entry->elems, (char *)entry + entry->target_offset); } dump_match(entry); dump_target(entry); dump_ip(entry); return 0; } static void dump_table(struct connman_iptables *table) { DBG("%s valid_hooks=0x%08x, num_entries=%u, size=%u", table->info->name, table->info->valid_hooks, table->info->num_entries, table->info->size); DBG("entry hook: pre/in/fwd/out/post %d/%d/%d/%d/%d", table->info->hook_entry[NF_IP_PRE_ROUTING], table->info->hook_entry[NF_IP_LOCAL_IN], table->info->hook_entry[NF_IP_FORWARD], table->info->hook_entry[NF_IP_LOCAL_OUT], table->info->hook_entry[NF_IP_POST_ROUTING]); DBG("underflow: pre/in/fwd/out/post %d/%d/%d/%d/%d", table->info->underflow[NF_IP_PRE_ROUTING], table->info->underflow[NF_IP_LOCAL_IN], table->info->underflow[NF_IP_FORWARD], table->info->underflow[NF_IP_LOCAL_OUT], table->info->underflow[NF_IP_POST_ROUTING]); iterate_entries(table->blob_entries->entrytable, table->info->valid_hooks, table->info->hook_entry, table->info->underflow, table->blob_entries->size, print_entry, dump_entry); } static void dump_ipt_replace(struct ipt_replace *repl) { DBG("%s valid_hooks 0x%08x num_entries %u size %u", repl->name, repl->valid_hooks, repl->num_entries, repl->size); DBG("entry hook: pre/in/fwd/out/post %d/%d/%d/%d/%d", repl->hook_entry[NF_IP_PRE_ROUTING], repl->hook_entry[NF_IP_LOCAL_IN], repl->hook_entry[NF_IP_FORWARD], repl->hook_entry[NF_IP_LOCAL_OUT], repl->hook_entry[NF_IP_POST_ROUTING]); DBG("underflow: pre/in/fwd/out/post %d/%d/%d/%d/%d", repl->underflow[NF_IP_PRE_ROUTING], repl->underflow[NF_IP_LOCAL_IN], repl->underflow[NF_IP_FORWARD], repl->underflow[NF_IP_LOCAL_OUT], repl->underflow[NF_IP_POST_ROUTING]); iterate_entries(repl->entries, repl->valid_hooks, repl->hook_entry, repl->underflow, repl->size, print_entry, dump_entry); } static int iptables_get_entries(struct connman_iptables *table) { socklen_t entry_size; entry_size = sizeof(struct ipt_get_entries) + table->info->size; return getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_ENTRIES, table->blob_entries, &entry_size); } static int iptables_replace(struct connman_iptables *table, struct ipt_replace *r) { return setsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_SET_REPLACE, r, sizeof(*r) + r->size); } static int add_entry(struct ipt_entry *entry, int builtin, unsigned int hook, size_t size, unsigned offset, void *user_data) { struct connman_iptables *table = user_data; struct ipt_entry *new_entry; new_entry = g_try_malloc0(entry->next_offset); if (new_entry == NULL) return -ENOMEM; memcpy(new_entry, entry, entry->next_offset); return iptables_add_entry(table, new_entry, NULL, builtin); } static void table_cleanup(struct connman_iptables *table) { GList *list; struct connman_iptables_entry *entry; if (table == NULL) return; if (table->ipt_sock >= 0) close(table->ipt_sock); for (list = table->entries; list; list = list->next) { entry = list->data; g_free(entry->entry); g_free(entry); } g_list_free(table->entries); g_free(table->info); g_free(table->blob_entries); g_free(table); } static struct connman_iptables *iptables_init(const char *table_name) { struct connman_iptables *table = NULL; char *module = NULL; socklen_t s; if (table_name == NULL) table_name = "filter"; DBG("%s", table_name); if (xtables_insmod("ip_tables", NULL, TRUE) != 0) DBG("ip_tables module loading gives error but trying anyway"); module = g_strconcat("iptable_", table_name, NULL); if (module == NULL) return NULL; if (xtables_insmod(module, NULL, TRUE) != 0) DBG("%s module loading gives error but trying anyway", module); g_free(module); table = g_hash_table_lookup(table_hash, table_name); if (table != NULL) return table; table = g_try_new0(struct connman_iptables, 1); if (table == NULL) return NULL; table->info = g_try_new0(struct ipt_getinfo, 1); if (table->info == NULL) goto err; table->ipt_sock = socket(AF_INET, SOCK_RAW | SOCK_CLOEXEC, IPPROTO_RAW); if (table->ipt_sock < 0) goto err; s = sizeof(*table->info); strcpy(table->info->name, table_name); if (getsockopt(table->ipt_sock, IPPROTO_IP, IPT_SO_GET_INFO, table->info, &s) < 0) { connman_error("iptables support missing error %d (%s)", errno, strerror(errno)); goto err; } table->blob_entries = g_try_malloc0(sizeof(struct ipt_get_entries) + table->info->size); if (table->blob_entries == NULL) goto err; strcpy(table->blob_entries->name, table_name); table->blob_entries->size = table->info->size; if (iptables_get_entries(table) < 0) goto err; table->num_entries = 0; table->old_entries = table->info->num_entries; table->size = 0; memcpy(table->underflow, table->info->underflow, sizeof(table->info->underflow)); memcpy(table->hook_entry, table->info->hook_entry, sizeof(table->info->hook_entry)); iterate_entries(table->blob_entries->entrytable, table->info->valid_hooks, table->info->hook_entry, table->info->underflow, table->blob_entries->size, add_entry, table); g_hash_table_insert(table_hash, g_strdup(table_name), table); if (debug_enabled == TRUE) dump_table(table); return table; err: table_cleanup(table); return NULL; } static struct option iptables_opts[] = { {.name = "append", .has_arg = 1, .val = 'A'}, {.name = "compare", .has_arg = 1, .val = 'C'}, {.name = "delete", .has_arg = 1, .val = 'D'}, {.name = "flush-chain", .has_arg = 1, .val = 'F'}, {.name = "insert", .has_arg = 1, .val = 'I'}, {.name = "list", .has_arg = 2, .val = 'L'}, {.name = "new-chain", .has_arg = 1, .val = 'N'}, {.name = "policy", .has_arg = 1, .val = 'P'}, {.name = "delete-chain", .has_arg = 1, .val = 'X'}, {.name = "destination", .has_arg = 1, .val = 'd'}, {.name = "in-interface", .has_arg = 1, .val = 'i'}, {.name = "jump", .has_arg = 1, .val = 'j'}, {.name = "match", .has_arg = 1, .val = 'm'}, {.name = "out-interface", .has_arg = 1, .val = 'o'}, {.name = "source", .has_arg = 1, .val = 's'}, {.name = "table", .has_arg = 1, .val = 't'}, {NULL}, }; struct xtables_globals iptables_globals = { .option_offset = 0, .opts = iptables_opts, .orig_opts = iptables_opts, }; static struct xtables_target *prepare_target(struct connman_iptables *table, const char *target_name) { struct xtables_target *xt_t = NULL; gboolean is_builtin, is_user_defined; GList *chain_head = NULL; size_t target_size; is_builtin = FALSE; is_user_defined = FALSE; if (is_builtin_target(target_name)) is_builtin = TRUE; else { chain_head = find_chain_head(table, target_name); if (chain_head != NULL && chain_head->next != NULL) is_user_defined = TRUE; } if (is_builtin || is_user_defined) xt_t = xtables_find_target(IPT_STANDARD_TARGET, XTF_LOAD_MUST_SUCCEED); else xt_t = xtables_find_target(target_name, XTF_TRY_LOAD); if (xt_t == NULL) return NULL; target_size = ALIGN(sizeof(struct ipt_entry_target)) + xt_t->size; xt_t->t = g_try_malloc0(target_size); if (xt_t->t == NULL) return NULL; xt_t->t->u.target_size = target_size; if (is_builtin || is_user_defined) { struct xt_standard_target *target; target = (struct xt_standard_target *)(xt_t->t); strcpy(target->target.u.user.name, IPT_STANDARD_TARGET); if (is_builtin == TRUE) target->verdict = target_to_verdict(target_name); else if (is_user_defined == TRUE) { struct connman_iptables_entry *target_rule; if (chain_head == NULL) { g_free(xt_t->t); return NULL; } target_rule = chain_head->next->data; target->verdict = target_rule->offset; } } else { strcpy(xt_t->t->u.user.name, target_name); xt_t->t->u.user.revision = xt_t->revision; if (xt_t->init != NULL) xt_t->init(xt_t->t); } #if XTABLES_VERSION_CODE > 5 if (xt_t->x6_options != NULL) iptables_globals.opts = xtables_options_xfrm( iptables_globals.orig_opts, iptables_globals.opts, xt_t->x6_options, &xt_t->option_offset); else #endif iptables_globals.opts = xtables_merge_options( #if XTABLES_VERSION_CODE > 5 iptables_globals.orig_opts, #endif iptables_globals.opts, xt_t->extra_opts, &xt_t->option_offset); if (iptables_globals.opts == NULL) { g_free(xt_t->t); xt_t = NULL; } return xt_t; } static struct xtables_match *prepare_matches(struct connman_iptables *table, struct xtables_rule_match **xt_rm, const char *match_name) { struct xtables_match *xt_m; size_t match_size; if (match_name == NULL) return NULL; xt_m = xtables_find_match(match_name, XTF_LOAD_MUST_SUCCEED, xt_rm); match_size = ALIGN(sizeof(struct ipt_entry_match)) + xt_m->size; xt_m->m = g_try_malloc0(match_size); if (xt_m->m == NULL) return NULL; xt_m->m->u.match_size = match_size; strcpy(xt_m->m->u.user.name, xt_m->name); xt_m->m->u.user.revision = xt_m->revision; if (xt_m->init != NULL) xt_m->init(xt_m->m); if (xt_m == xt_m->next) goto done; #if XTABLES_VERSION_CODE > 5 if (xt_m->x6_options != NULL) iptables_globals.opts = xtables_options_xfrm( iptables_globals.orig_opts, iptables_globals.opts, xt_m->x6_options, &xt_m->option_offset); else #endif iptables_globals.opts = xtables_merge_options( #if XTABLES_VERSION_CODE > 5 iptables_globals.orig_opts, #endif iptables_globals.opts, xt_m->extra_opts, &xt_m->option_offset); if (iptables_globals.opts == NULL) { g_free(xt_m->m); xt_m = NULL; } done: return xt_m; } static int parse_ip_and_mask(const char *str, struct in_addr *ip, struct in_addr *mask) { char **tokens; uint32_t prefixlength; uint32_t tmp; int err; tokens = g_strsplit(str, "/", 2); if (tokens == NULL) return -1; if (!inet_pton(AF_INET, tokens[0], ip)) { err = -1; goto out; } if (tokens[1] != NULL) { prefixlength = strtol(tokens[1], NULL, 10); if (prefixlength > 31) { err = -1; goto out; } tmp = ~(0xffffffff >> prefixlength); } else { tmp = 0xffffffff; } mask->s_addr = htonl(tmp); ip->s_addr = ip->s_addr & mask->s_addr; err = 0; out: g_strfreev(tokens); return err; } static struct connman_iptables *pre_load_table(const char *table_name, struct connman_iptables *table) { if (table != NULL) return table; return iptables_init(table_name); } struct parse_context { int argc; char **argv; struct ipt_ip *ip; struct xtables_target *xt_t; struct xtables_match *xt_m; struct xtables_rule_match *xt_rm; }; static int prepare_getopt_args(const char *str, struct parse_context *ctx) { char **tokens; int i; tokens = g_strsplit_set(str, " ", -1); i = g_strv_length(tokens); /* Add space for the argv[0] value */ ctx->argc = i + 1; /* Don't forget the last NULL entry */ ctx->argv = g_try_malloc0((ctx->argc + 1) * sizeof(char *)); if (ctx->argv == NULL) { g_strfreev(tokens); return -ENOMEM; } /* * getopt_long() jumps over the first token; we need to add some * random argv[0] entry. */ ctx->argv[0] = g_strdup("argh"); for (i = 1; i < ctx->argc; i++) ctx->argv[i] = tokens[i - 1]; g_free(tokens); return 0; } #if XTABLES_VERSION_CODE > 5 static int parse_xt_modules(int c, connman_bool_t invert, struct parse_context *ctx) { struct xtables_match *m; struct xtables_rule_match *rm; DBG("xtables version code > 5"); for (rm = ctx->xt_rm; rm != NULL; rm = rm->next) { if (rm->completed != 0) continue; m = rm->match; if (m->x6_parse == NULL && m->parse == NULL) continue; if (c < (int) m->option_offset || c >= (int) m->option_offset + XT_OPTION_OFFSET_SCALE) continue; xtables_option_mpcall(c, ctx->argv, invert, m, NULL); } if (ctx->xt_t == NULL) return 0; if (ctx->xt_t->x6_parse == NULL && ctx->xt_t->parse == NULL) return 0; if (c < (int) ctx->xt_t->option_offset || c >= (int) ctx->xt_t->option_offset + XT_OPTION_OFFSET_SCALE) return 0; xtables_option_tpcall(c, ctx->argv, invert, ctx->xt_t, NULL); return 0; } static int final_check_xt_modules(struct parse_context *ctx) { struct xtables_rule_match *rm; DBG("xtables version code > 5"); for (rm = ctx->xt_rm; rm != NULL; rm = rm->next) xtables_option_mfcall(rm->match); if (ctx->xt_t != NULL) xtables_option_tfcall(ctx->xt_t); return 0; } #else static int parse_xt_modules(int c, connman_bool_t invert, struct parse_context *ctx) { struct xtables_match *m; struct xtables_rule_match *rm; int err; DBG("xtables version code <= 5"); for (rm = ctx->xt_rm; rm != NULL; rm = rm->next) { if (rm->completed == 1) continue; m = rm->match; if (m->parse == NULL) continue; err = m->parse(c - m->option_offset, argv, invert, &m->mflags, NULL, &m->m); if (err > 0) return -err; } if (ctx->xt_t == NULL) return 0; if (ctx->xt_t->parse == NULL) return 0; err = ctx->xt_m->parse(c - ctx->xt_m->option_offset, ctx->argv, invert, &ctx->xt_m->mflags, NULL, &ctx->xt_m->m); return -err; } static int final_check_xt_modules(struct parse_context *ctx) { struct xtables_rule_match *rm; DBG("xtables version code <= 5"); for (rm = ctx->xt_rm; rm != NULL; rm = rm->next) if (rm->match->final_check != NULL) rm->match->final_check(rm->match->mflags); if (ctx->xt_t != NULL && ctx->xt_t->final_check != NULL) ctx->xt_t->final_check(ctx->xt_t->tflags); return 0; } #endif static int parse_rule_spec(struct connman_iptables *table, struct parse_context *ctx) { /* * How the parser works: * * - If getopt finds 's', 'd', 'i', 'o'. * just extract the information. * - if '!' is found, set the invert flag to true and * removes the '!' from the optarg string and jumps * back to getopt to reparse the current optarg string. * After reparsing the invert flag is reseted to false. * - If 'm' or 'j' is found then call either * prepare_matches() or prepare_target(). Those function * will modify (extend) the longopts for getopt_long. * That means getopt will change its matching context according * the loaded target. * * Here an example with iptables-test * * argv[0] = ./tools/iptables-test * argv[1] = -t * argv[2] = filter * argv[3] = -A * argv[4] = INPUT * argv[5] = -m * argv[6] = mark * argv[7] = --mark * argv[8] = 999 * argv[9] = -j * argv[10] = LOG * * getopt found 'm' then the optarg is "mark" and optind 7 * The longopts array containts before hitting the `case 'm'` * * val A has_arg 1 name append * val C has_arg 1 name compare * val D has_arg 1 name delete * val F has_arg 1 name flush-chain * val I has_arg 1 name insert * val L has_arg 2 name list * val N has_arg 1 name new-chain * val P has_arg 1 name policy * val X has_arg 1 name delete-chain * val d has_arg 1 name destination * val i has_arg 1 name in-interface * val j has_arg 1 name jump * val m has_arg 1 name match * val o has_arg 1 name out-interface * val s has_arg 1 name source * val t has_arg 1 name table * * After executing the `case 'm'` block longopts is * * val A has_arg 1 name append * val C has_arg 1 name compare * val D has_arg 1 name delete * val F has_arg 1 name flush-chain * val I has_arg 1 name insert * val L has_arg 2 name list * val N has_arg 1 name new-chain * val P has_arg 1 name policy * val X has_arg 1 name delete-chain * val d has_arg 1 name destination * val i has_arg 1 name in-interface * val j has_arg 1 name jump * val m has_arg 1 name match * val o has_arg 1 name out-interface * val s has_arg 1 name source * val t has_arg 1 name table * val has_arg 1 name mark * * So the 'mark' matcher has added the 'mark' options * and getopt will then return c '256' optarg "999" optind 9 * And we will hit the 'default' statement which then * will call the matchers parser (xt_m->parser() or * xtables_option_mpcall() depending on which version * of libxtables is found. */ connman_bool_t invert = FALSE; int len, c, err; DBG(""); ctx->ip = g_try_new0(struct ipt_ip, 1); if (ctx->ip == NULL) return -ENOMEM; /* * Tell getopt_long not to generate error messages for unknown * options and also reset optind back to 0. */ opterr = 0; optind = 0; while ((c = getopt_long(ctx->argc, ctx->argv, "-:d:i:o:s:m:j:", iptables_globals.opts, NULL)) != -1) { switch (c) { case 's': /* Source specification */ if (!parse_ip_and_mask(optarg, &ctx->ip->src, &ctx->ip->smsk)) break; if (invert) ctx->ip->invflags |= IPT_INV_SRCIP; break; case 'd': /* Destination specification */ if (!parse_ip_and_mask(optarg, &ctx->ip->dst, &ctx->ip->dmsk)) break; if (invert) ctx->ip->invflags |= IPT_INV_DSTIP; break; case 'i': /* In interface specification */ len = strlen(optarg); if (len + 1 > IFNAMSIZ) break; strcpy(ctx->ip->iniface, optarg); memset(ctx->ip->iniface_mask, 0xff, len + 1); if (invert) ctx->ip->invflags |= IPT_INV_VIA_IN; break; case 'o': /* Out interface specification */ len = strlen(optarg); if (len + 1 > IFNAMSIZ) break; strcpy(ctx->ip->outiface, optarg); memset(ctx->ip->outiface_mask, 0xff, len + 1); if (invert) ctx->ip->invflags |= IPT_INV_VIA_OUT; break; case 'm': /* Matches */ ctx->xt_m = prepare_matches(table, &ctx->xt_rm, optarg); if (ctx->xt_m == NULL) { err = -EINVAL; goto out; } break; case 'j': /* Target */ ctx->xt_t = prepare_target(table, optarg); if (ctx->xt_t == NULL) { err = -EINVAL; goto out; } break; case 1: if (optarg[0] == '!' && optarg[1] == '\0') { invert = TRUE; /* Remove the '!' from the optarg */ optarg[0] = '\0'; /* * And recall getopt_long without reseting * invert. */ continue; } break; default: err = parse_xt_modules(c, invert, ctx); if (err == 1) continue; break; } invert = FALSE; } err = final_check_xt_modules(ctx); out: return err; } static void reset_xtables(void) { struct xtables_match *xt_m; struct xtables_target *xt_t; /* * As side effect parsing a rule sets some global flags * which will be evaluated/verified. Let's reset them * to ensure we can parse more than one rule. * * Clear all flags because the flags are only valid * for one rule. */ for (xt_m = xtables_matches; xt_m != NULL; xt_m = xt_m->next) xt_m->mflags = 0; for (xt_t = xtables_targets; xt_t != NULL; xt_t = xt_t->next) { xt_t->tflags = 0; xt_t->used = 0; } /* * We need also to free the memory implicitly allocated * during parsing (see xtables_options_xfrm()). * Note xt_params is actually iptables_globals. */ if (xt_params->opts != xt_params->orig_opts) { g_free(xt_params->opts); xt_params->opts = xt_params->orig_opts; } xt_params->option_offset = 0; } static void cleanup_parse_context(struct parse_context *ctx) { struct xtables_rule_match *rm, *tmp; g_strfreev(ctx->argv); g_free(ctx->ip); if (ctx->xt_t != NULL) { g_free(ctx->xt_t->t); ctx->xt_t->t = NULL; } if (ctx->xt_m != NULL) { g_free(ctx->xt_m->m); ctx->xt_m->m = NULL; } for (tmp = NULL, rm = ctx->xt_rm; rm != NULL; rm = rm->next) { if (tmp != NULL) g_free(tmp); tmp = rm; } g_free(tmp); g_free(ctx); } int __connman_iptables_new_chain(const char *table_name, const char *chain) { struct connman_iptables *table; DBG("-t %s -N %s", table_name, chain); table = pre_load_table(table_name, NULL); if (table == NULL) return -EINVAL; return iptables_add_chain(table, chain); } int __connman_iptables_delete_chain(const char *table_name, const char *chain) { struct connman_iptables *table; DBG("-t %s -X %s", table_name, chain); table = pre_load_table(table_name, NULL); if (table == NULL) return -EINVAL; return iptables_delete_chain(table, chain); } int __connman_iptables_flush_chain(const char *table_name, const char *chain) { struct connman_iptables *table; DBG("-t %s -F %s", table_name, chain); table = pre_load_table(table_name, NULL); if (table == NULL) return -EINVAL; return iptables_flush_chain(table, chain); } int __connman_iptables_change_policy(const char *table_name, const char *chain, const char *policy) { struct connman_iptables *table; DBG("-t %s -F %s", table_name, chain); table = pre_load_table(table_name, NULL); if (table == NULL) return -EINVAL; return iptables_change_policy(table, chain, policy); } int __connman_iptables_append(const char *table_name, const char *chain, const char *rule_spec) { struct connman_iptables *table; struct parse_context *ctx; const char *target_name; int err; ctx = g_try_new0(struct parse_context, 1); if (ctx == NULL) return -ENOMEM; DBG("-t %s -A %s %s", table_name, chain, rule_spec); err = prepare_getopt_args(rule_spec, ctx); if (err < 0) goto out; table = pre_load_table(table_name, NULL); if (table == NULL) { err = -EINVAL; goto out; } err = parse_rule_spec(table, ctx); if (err < 0) goto out; if (ctx->xt_t == NULL) target_name = NULL; else target_name = ctx->xt_t->name; err = iptables_insert_rule(table, ctx->ip, chain, target_name, ctx->xt_t, ctx->xt_rm); out: cleanup_parse_context(ctx); reset_xtables(); return err; } int __connman_iptables_delete(const char *table_name, const char *chain, const char *rule_spec) { struct connman_iptables *table; struct parse_context *ctx; const char *target_name; int err; ctx = g_try_new0(struct parse_context, 1); if (ctx == NULL) return -ENOMEM; DBG("-t %s -D %s %s", table_name, chain, rule_spec); err = prepare_getopt_args(rule_spec, ctx); if (err < 0) goto out; table = pre_load_table(table_name, NULL); if (table == NULL) { err = -EINVAL; goto out; } err = parse_rule_spec(table, ctx); if (err < 0) goto out; if (ctx->xt_t == NULL) target_name = NULL; else target_name = ctx->xt_t->name; err = iptables_delete_rule(table, ctx->ip, chain, target_name, ctx->xt_t, ctx->xt_m, ctx->xt_rm); out: cleanup_parse_context(ctx); reset_xtables(); return err; } int __connman_iptables_commit(const char *table_name) { struct connman_iptables *table; struct ipt_replace *repl; int err; DBG("%s", table_name); table = g_hash_table_lookup(table_hash, table_name); if (table == NULL) return -EINVAL; repl = iptables_blob(table); if (debug_enabled == TRUE) dump_ipt_replace(repl); err = iptables_replace(table, repl); g_free(repl->counters); g_free(repl); if (err < 0) return err; g_hash_table_remove(table_hash, table_name); return 0; } static void remove_table(gpointer user_data) { struct connman_iptables *table = user_data; table_cleanup(table); } static int flush_table_cb(struct ipt_entry *entry, int builtin, unsigned int hook, size_t size, unsigned int offset, void *user_data) { GSList **chains = user_data; struct xt_entry_target *target; char *name; if (offset + entry->next_offset == size) return 0; target = ipt_get_target(entry); if (!strcmp(target->u.user.name, IPT_ERROR_TARGET)) name = g_strdup((const char*)target->data); else if (builtin >= 0) name = g_strdup(hooknames[builtin]); else return 0; *chains = g_slist_prepend(*chains, name); return 0; } void flush_table(const char *name) { GSList *chains = NULL, *list; struct connman_iptables *table; table = pre_load_table(name, NULL); if (table == NULL) return; iterate_entries(table->blob_entries->entrytable, table->info->valid_hooks, table->info->hook_entry, table->info->underflow, table->blob_entries->size, flush_table_cb, &chains); for (list = chains; list != NULL; list = list->next) { char *chain = list->data; DBG("chain %s", chain); iptables_flush_chain(table, chain); } __connman_iptables_commit(name); g_slist_free_full(chains, g_free); } int __connman_iptables_init(void) { DBG(""); if (getenv("CONNMAN_IPTABLES_DEBUG")) debug_enabled = TRUE; table_hash = g_hash_table_new_full(g_str_hash, g_str_equal, g_free, remove_table); xtables_init_all(&iptables_globals, NFPROTO_IPV4); return 0; } void __connman_iptables_cleanup(void) { DBG(""); g_hash_table_destroy(table_hash); }