service: Simplify nameserver route adding and removing
[framework/connectivity/connman.git] / src / iptables.c
index 16c3701..531e933 100644 (file)
@@ -2,7 +2,7 @@
  *
  *  Connection Manager
  *
- *  Copyright (C) 2007-2011  Intel Corporation. All rights reserved.
+ *  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
@@ -538,15 +538,15 @@ static int iptables_delete_chain(struct connman_iptables *table, char *name)
 
 static struct ipt_entry *new_rule(struct ipt_ip *ip,
                char *target_name, struct xtables_target *xt_t,
-               char *match_name, struct xtables_match *xt_m)
+               struct xtables_rule_match *xt_rm)
 {
+       struct xtables_rule_match *tmp_xt_rm;
        struct ipt_entry *new_entry;
        size_t match_size, target_size;
 
-       if (xt_m)
-               match_size = xt_m->m->u.match_size;
-       else
-               match_size = 0;
+       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);
@@ -563,11 +563,13 @@ static struct ipt_entry *new_rule(struct ipt_ip *ip,
        new_entry->target_offset = sizeof(struct ipt_entry) + match_size;
        new_entry->next_offset = sizeof(struct ipt_entry) + target_size +
                                                                match_size;
-       if (xt_m) {
-               struct xt_entry_match *entry_match;
 
-               entry_match = (struct xt_entry_match *)new_entry->elems;
-               memcpy(entry_match, xt_m->m, 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) {
@@ -613,8 +615,7 @@ static void update_hooks(struct connman_iptables *table, GList *chain_head,
 static struct ipt_entry *prepare_rule_inclusion(struct connman_iptables *table,
                                struct ipt_ip *ip, char *chain_name,
                                char *target_name, struct xtables_target *xt_t,
-                               char *match_name, struct xtables_match *xt_m,
-                               int *builtin)
+                               int *builtin, struct xtables_rule_match *xt_rm)
 {
        GList *chain_tail, *chain_head;
        struct ipt_entry *new_entry;
@@ -628,7 +629,7 @@ static struct ipt_entry *prepare_rule_inclusion(struct connman_iptables *table,
        if (chain_tail == NULL)
                return NULL;
 
-       new_entry = new_rule(ip, target_name, xt_t, match_name, xt_m);
+       new_entry = new_rule(ip, target_name, xt_t, xt_rm);
        if (new_entry == NULL)
                return NULL;
 
@@ -653,7 +654,7 @@ static struct ipt_entry *prepare_rule_inclusion(struct connman_iptables *table,
 static int iptables_append_rule(struct connman_iptables *table,
                                struct ipt_ip *ip, char *chain_name,
                                char *target_name, struct xtables_target *xt_t,
-                               char *match_name, struct xtables_match *xt_m)
+                               struct xtables_rule_match *xt_rm)
 {
        GList *chain_tail;
        struct ipt_entry *new_entry;
@@ -666,7 +667,7 @@ static int iptables_append_rule(struct connman_iptables *table,
                return -EINVAL;
 
        new_entry = prepare_rule_inclusion(table, ip, chain_name,
-                       target_name, xt_t, match_name, xt_m, &builtin);
+                                       target_name, xt_t, &builtin, xt_rm);
        if (new_entry == NULL)
                return -EINVAL;
 
@@ -680,7 +681,7 @@ static int iptables_append_rule(struct connman_iptables *table,
 static int iptables_insert_rule(struct connman_iptables *table,
                                struct ipt_ip *ip, char *chain_name,
                                char *target_name, struct xtables_target *xt_t,
-                               char *match_name, struct xtables_match *xt_m)
+                               struct xtables_rule_match *xt_rm)
 {
        struct ipt_entry *new_entry;
        int builtin = -1, ret;
@@ -691,11 +692,14 @@ static int iptables_insert_rule(struct connman_iptables *table,
                return -EINVAL;
 
        new_entry = prepare_rule_inclusion(table, ip, chain_name,
-                       target_name, xt_t, match_name, xt_m, &builtin);
+                                       target_name, xt_t, &builtin, xt_rm);
        if (new_entry == NULL)
                return -EINVAL;
 
-       ret = iptables_add_entry(table, new_entry, chain_head->next, builtin);
+       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);
 
@@ -761,34 +765,33 @@ static gboolean is_same_match(struct xt_entry_match *xt_e_m1,
        return TRUE;
 }
 
-static int iptables_delete_rule(struct connman_iptables *table,
+static GList *find_existing_rule(struct connman_iptables *table,
                                struct ipt_ip *ip, char *chain_name,
                                char *target_name, struct xtables_target *xt_t,
-                               char *match_name, struct xtables_match *xt_m)
+                               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, removed;
-
-       removed = 0;
+       int builtin;
 
        chain_head = find_chain_head(table, chain_name);
        if (chain_head == NULL)
-               return -EINVAL;
+               return NULL;
 
        chain_tail = find_chain_tail(table, chain_name);
        if (chain_tail == NULL)
-               return -EINVAL;
+               return NULL;
 
        if (!xt_t && !xt_m)
-               return -EINVAL;
+               return NULL;
 
-       entry_test = new_rule(ip, target_name, xt_t, match_name, xt_m);
+       entry_test = new_rule(ip, target_name, xt_t, xt_rm);
        if (entry_test == NULL)
-               return -EINVAL;
+               return NULL;
 
        if (xt_t != NULL)
                xt_e_t = ipt_get_target(entry_test);
@@ -803,7 +806,7 @@ static int iptables_delete_rule(struct connman_iptables *table,
        else
                list = chain_head->next;
 
-       for (entry = NULL; list != chain_tail->prev; list = list->next) {
+       for (; list != chain_tail->prev; list = list->next) {
                struct connman_iptables_entry *tmp;
                struct ipt_entry *tmp_e;
 
@@ -831,14 +834,43 @@ static int iptables_delete_rule(struct connman_iptables *table,
                                continue;
                }
 
-               entry = tmp;
                break;
        }
 
-       if (entry == NULL) {
-               g_free(entry_test);
+       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, char *chain_name,
+                               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_tail, *list;
+       int builtin, removed;
+
+       removed = 0;
+
+       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 = list->data;
+       if (entry == NULL)
+               return -EINVAL;
+
+       builtin = entry->builtin;
 
        /* We have deleted a rule,
         * all references should be bumped accordingly */
@@ -873,6 +905,57 @@ static int iptables_delete_rule(struct connman_iptables *table,
        return 0;
 }
 
+static int iptables_compare_rule(struct connman_iptables *table,
+                               struct ipt_ip *ip, char *chain_name,
+                               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 *found;
+
+       found = find_existing_rule(table, ip, chain_name, target_name,
+                                                       xt_t, xt_m, xt_rm);
+       if (found == NULL)
+               return -EINVAL;
+
+       entry = found->data;
+       if (entry == NULL)
+               return -EINVAL;
+
+       return 0;
+}
+
+
+static int iptables_change_policy(struct connman_iptables *table,
+                                       char *chain_name, 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;
@@ -1121,6 +1204,9 @@ static void table_cleanup(struct connman_iptables *table)
        GList *list;
        struct connman_iptables_entry *entry;
 
+       if (table == NULL)
+               return;
+
        close(table->ipt_sock);
 
        for (list = table->entries; list; list = list->next) {
@@ -1145,17 +1231,18 @@ static struct connman_iptables *iptables_init(char *table_name)
        DBG("%s", table_name);
 
        if (xtables_insmod("ip_tables", NULL, TRUE) != 0)
-               goto err;
+               return NULL;
 
        module = g_strconcat("iptable_", table_name, NULL);
        if (module == NULL)
-               goto err;
+               return NULL;
 
-       if (xtables_insmod(module, NULL, TRUE) != 0)
-               goto err;
+       if (xtables_insmod(module, NULL, TRUE) != 0) {
+               g_free(module);
+               return NULL;
+       }
 
        g_free(module);
-       module = NULL;
 
        table = g_hash_table_lookup(table_hash, table_name);
        if (table != NULL)
@@ -1208,8 +1295,6 @@ static struct connman_iptables *iptables_init(char *table_name)
        return table;
 
 err:
-       g_free(module);
-
        table_cleanup(table);
 
        return NULL;
@@ -1217,11 +1302,13 @@ err:
 
 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'},
@@ -1301,16 +1388,16 @@ static struct xtables_target *prepare_target(struct connman_iptables *table,
                        xt_t->init(xt_t->t);
        }
 
+#if XTABLES_VERSION_CODE > 5
        if (xt_t->x6_options != NULL)
                iptables_globals.opts =
                        xtables_options_xfrm(
-#if XTABLES_VERSION_CODE > 5
                                iptables_globals.orig_opts,
-#endif
                                iptables_globals.opts,
                                xt_t->x6_options,
                                &xt_t->option_offset);
        else
+#endif
                iptables_globals.opts =
                        xtables_merge_options(
 #if XTABLES_VERSION_CODE > 5
@@ -1354,16 +1441,16 @@ static struct xtables_match *prepare_matches(struct connman_iptables *table,
        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(
-#if XTABLES_VERSION_CODE > 5
                                iptables_globals.orig_opts,
-#endif
                                iptables_globals.opts,
                                xt_m->x6_options,
                                &xt_m->option_offset);
        else
+#endif
                        iptables_globals.opts =
                        xtables_merge_options(
 #if XTABLES_VERSION_CODE > 5
@@ -1382,6 +1469,43 @@ 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 int iptables_command(int argc, char *argv[])
 {
        struct connman_iptables *table;
@@ -1390,10 +1514,9 @@ static int iptables_command(int argc, char *argv[])
        struct xtables_target *xt_t;
        struct ipt_ip ip;
        char *table_name, *chain, *new_chain, *match_name, *target_name;
-       char *flush_chain, *delete_chain;
+       char *flush_chain, *delete_chain, *policy;
        int c, ret, in_len, out_len;
-       gboolean dump, invert, insert, delete;
-       struct in_addr src, dst;
+       gboolean dump, invert, insert, delete, compare;
 
        if (argc == 0)
                return -EINVAL;
@@ -1402,8 +1525,9 @@ static int iptables_command(int argc, char *argv[])
        invert = FALSE;
        insert = FALSE;
        delete = FALSE;
-       table_name = chain = new_chain = match_name = target_name = NULL;
-       flush_chain = delete_chain = NULL;
+       compare = FALSE;
+       chain = new_chain = match_name = target_name = NULL;
+       flush_chain = delete_chain = policy = NULL;
        memset(&ip, 0, sizeof(struct ipt_ip));
        table = NULL;
        xt_rm = NULL;
@@ -1411,21 +1535,34 @@ static int iptables_command(int argc, char *argv[])
        xt_t = NULL;
        ret = 0;
 
+       /* extension's options will generate false-positives errors */
+       opterr = 0;
+
        optind = 0;
 
-       while ((c = getopt_long(argc, argv, "-A:F:I:L::N:X:d:j:i:m:o:s:t:",
+       while ((c = getopt_long(argc, argv,
+                                       "-A:C:D:F:I:L::N:P:X:d:j:i:m:o:s:t:",
                                        iptables_globals.opts, NULL)) != -1) {
                switch (c) {
                case 'A':
-                       /* It is either -A, -D or -I at once */
+                       /* It is either -A, -C, -D or -I at once */
                        if (chain)
                                goto out;
 
                        chain = optarg;
                        break;
 
+               case 'C':
+                       /* It is either -A, -C, -D or -I at once */
+                       if (chain)
+                               goto out;
+
+                       chain = optarg;
+                       compare = TRUE;
+                       break;
+
                case 'D':
-                       /* It is either -A, -D or -I at once */
+                       /* It is either -A, -C, -D or -I at once */
                        if (chain)
                                goto out;
 
@@ -1438,7 +1575,7 @@ static int iptables_command(int argc, char *argv[])
                        break;
 
                case 'I':
-                       /* It is either -A, -D or -I at once */
+                       /* It is either -A, -C, -D or -I at once */
                        if (chain)
                                goto out;
 
@@ -1454,17 +1591,23 @@ static int iptables_command(int argc, char *argv[])
                        new_chain = optarg;
                        break;
 
+               case 'P':
+                       chain = optarg;
+                       if (optind < argc)
+                               policy = argv[optind++];
+                       else
+                               goto out;
+
+                       break;
+
                case 'X':
                        delete_chain = optarg;
                        break;
 
                case 'd':
-                       if (!inet_pton(AF_INET, optarg, &dst))
+                       if (!parse_ip_and_mask(optarg, &ip.dst, &ip.dmsk))
                                break;
 
-                       ip.dst = dst;
-                       inet_pton(AF_INET, "255.255.255.255", &ip.dmsk);
-
                        if (invert)
                                ip.invflags |= IPT_INV_DSTIP;
 
@@ -1515,12 +1658,9 @@ static int iptables_command(int argc, char *argv[])
                        break;
 
                case 's':
-                       if (!inet_pton(AF_INET, optarg, &src))
+                       if (!parse_ip_and_mask(optarg, &ip.src, &ip.smsk))
                                break;
 
-                       ip.src = src;
-                       inet_pton(AF_INET, "255.255.255.255", &ip.smsk);
-
                        if (invert)
                                ip.invflags |= IPT_INV_SRCIP;
 
@@ -1528,6 +1668,13 @@ static int iptables_command(int argc, char *argv[])
 
                case 't':
                        table_name = optarg;
+
+                       table = iptables_init(table_name);
+                       if (table == NULL) {
+                               ret = -EINVAL;
+                               goto out;
+                       }
+
                        break;
 
                case 1:
@@ -1543,6 +1690,7 @@ static int iptables_command(int argc, char *argv[])
                        goto out;
 
                default:
+#if XTABLES_VERSION_CODE > 5
                        if (xt_t != NULL && (xt_t->x6_parse != NULL ||
                                                xt_t->parse != NULL) &&
                                        (c >= (int) xt_t->option_offset &&
@@ -1573,27 +1721,58 @@ static int iptables_command(int argc, char *argv[])
 
                                break;
                        }
+#else
+                       if (xt_t == NULL || xt_t->parse == NULL ||
+                               !xt_t->parse(c - xt_t->option_offset,
+                               argv, invert, &xt_t->tflags, NULL, &xt_t->t)) {
+
+                               for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL;
+                                               tmp_xt_rm = tmp_xt_rm->next) {
+                                       xt_m_t = tmp_xt_rm->match;
 
+                                       if (tmp_xt_rm->completed ||
+                                                       xt_m_t->parse == NULL)
+                                               continue;
+
+                                       if (xt_m->parse(c - xt_m->option_offset,
+                                               argv, invert, &xt_m->mflags,
+                                               NULL, &xt_m->m))
+                                               break;
+                               }
+                       }
+#endif
                        break;
                }
 
                invert = FALSE;
        }
 
+#if XTABLES_VERSION_CODE > 5
        for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL;
                                tmp_xt_rm = tmp_xt_rm->next)
                xtables_option_mfcall(tmp_xt_rm->match);
 
        if (xt_t != NULL)
                xtables_option_tfcall(xt_t);
+#else
+       for (tmp_xt_rm = xt_rm; tmp_xt_rm != NULL;
+                               tmp_xt_rm = tmp_xt_rm->next)
+               if (tmp_xt_rm->match->final_check != NULL)
+                       tmp_xt_rm->match->final_check(
+                                       tmp_xt_rm->match->mflags);
 
-       if (table_name == NULL)
-               table_name = "filter";
+       if (xt_t != NULL && xt_t->final_check != NULL)
+               xt_t->final_check(xt_t->tflags);
+#endif
 
-       table = iptables_init(table_name);
        if (table == NULL) {
-               ret = -EINVAL;
-               goto out;
+               table_name = "filter";
+
+               table = iptables_init(table_name);
+               if (table == NULL) {
+                       ret = -EINVAL;
+                       goto out;
+               }
        }
 
        if (delete_chain != NULL) {
@@ -1632,15 +1811,29 @@ static int iptables_command(int argc, char *argv[])
        }
 
        if (chain) {
+               if (policy != NULL) {
+                       printf("Changing policy of %s to %s\n", chain, policy);
+
+                       iptables_change_policy(table, chain, policy);
+
+                       goto out;
+               }
+
                if (xt_t == NULL)
                        goto out;
 
+               if (compare == TRUE) {
+                       ret = iptables_compare_rule(table, &ip, chain,
+                                       target_name, xt_t, xt_m, xt_rm);
+                       goto out;
+               }
+
                if (delete == TRUE) {
                        DBG("Deleting %s to %s (match %s)\n",
                                        target_name, chain, match_name);
 
                        ret = iptables_delete_rule(table, &ip, chain,
-                                       target_name, xt_t, match_name, xt_m);
+                                       target_name, xt_t, xt_m, xt_rm);
 
                        goto out;
                }
@@ -1650,7 +1843,7 @@ static int iptables_command(int argc, char *argv[])
                                        target_name, chain, match_name);
 
                        ret = iptables_insert_rule(table, &ip, chain,
-                                       target_name, xt_t, match_name, xt_m);
+                                               target_name, xt_t, xt_rm);
 
                        goto out;
                } else {
@@ -1658,7 +1851,7 @@ static int iptables_command(int argc, char *argv[])
                                        target_name, chain, match_name);
 
                        ret = iptables_append_rule(table, &ip, chain,
-                                       target_name, xt_t, match_name, xt_m);
+                                               target_name, xt_t, xt_rm);
 
                        goto out;
                }