[ARP]: Introduce the arp_hdr_len helper.

[safe/jmp/linux-2.6] / net / ipv4 / netfilter / arp_tables.c

diff --git a/net/ipv4/netfilter/arp_tables.c b/net/ipv4/netfilter/arp_tables.c
index 060de95..9b59044 100644 (file)
--- a/net/ipv4/netfilter/arp_tables.c
+++ b/net/ipv4/netfilter/arp_tables.c
@@ -22,6 +22,7 @@
 #include <linux/mutex.h>
 #include <linux/err.h>
 #include <net/compat.h>
+#include <net/sock.h>
 #include <asm/uaccess.h>
 
 #include <linux/netfilter/x_tables.h>
@@ -232,10 +233,7 @@ unsigned int arpt_do_table(struct sk_buff *skb,
        void *table_base;
        struct xt_table_info *private;
 
-       /* ARP header, plus 2 device addresses, plus 2 IP addresses.  */
-       if (!pskb_may_pull(skb, (sizeof(struct arphdr) +
-                                (2 * skb->dev->addr_len) +
-                                (2 * sizeof(u32)))))
+       if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
                return NF_DROP;
 
        indev = in ? in->name : nulldevname;
@@ -850,7 +848,7 @@ static int compat_table_info(const struct xt_table_info *info,
 }
 #endif
 
-static int get_info(void __user *user, int *len, int compat)
+static int get_info(struct net *net, void __user *user, int *len, int compat)
 {
        char name[ARPT_TABLE_MAXNAMELEN];
        struct arpt_table *t;
@@ -870,7 +868,7 @@ static int get_info(void __user *user, int *len, int compat)
        if (compat)
                xt_compat_lock(NF_ARP);
 #endif
-       t = try_then_request_module(xt_find_table_lock(NF_ARP, name),
+       t = try_then_request_module(xt_find_table_lock(net, NF_ARP, name),
                                    "arptable_%s", name);
        if (t && !IS_ERR(t)) {
                struct arpt_getinfo info;
@@ -908,7 +906,8 @@ static int get_info(void __user *user, int *len, int compat)
        return ret;
 }
 
-static int get_entries(struct arpt_get_entries __user *uptr, int *len)
+static int get_entries(struct net *net, struct arpt_get_entries __user *uptr,
+                      int *len)
 {
        int ret;
        struct arpt_get_entries get;
@@ -926,7 +925,7 @@ static int get_entries(struct arpt_get_entries __user *uptr, int *len)
                return -EINVAL;
        }
 
-       t = xt_find_table_lock(NF_ARP, get.name);
+       t = xt_find_table_lock(net, NF_ARP, get.name);
        if (t && !IS_ERR(t)) {
                struct xt_table_info *private = t->private;
                duprintf("t->private->number = %u\n",
@@ -947,7 +946,8 @@ static int get_entries(struct arpt_get_entries __user *uptr, int *len)
        return ret;
 }
 
-static int __do_replace(const char *name, unsigned int valid_hooks,
+static int __do_replace(struct net *net, const char *name,
+                       unsigned int valid_hooks,
                        struct xt_table_info *newinfo,
                        unsigned int num_counters,
                        void __user *counters_ptr)
@@ -966,7 +966,7 @@ static int __do_replace(const char *name, unsigned int valid_hooks,
                goto out;
        }
 
-       t = try_then_request_module(xt_find_table_lock(NF_ARP, name),
+       t = try_then_request_module(xt_find_table_lock(net, NF_ARP, name),
                                    "arptable_%s", name);
        if (!t || IS_ERR(t)) {
                ret = t ? PTR_ERR(t) : -ENOENT;
@@ -1019,7 +1019,7 @@ static int __do_replace(const char *name, unsigned int valid_hooks,
        return ret;
 }
 
-static int do_replace(void __user *user, unsigned int len)
+static int do_replace(struct net *net, void __user *user, unsigned int len)
 {
        int ret;
        struct arpt_replace tmp;
@@ -1053,7 +1053,7 @@ static int do_replace(void __user *user, unsigned int len)
 
        duprintf("arp_tables: Translated table\n");
 
-       ret = __do_replace(tmp.name, tmp.valid_hooks, newinfo,
+       ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
                           tmp.num_counters, tmp.counters);
        if (ret)
                goto free_newinfo_untrans;
@@ -1080,7 +1080,8 @@ static inline int add_counter_to_entry(struct arpt_entry *e,
        return 0;
 }
 
-static int do_add_counters(void __user *user, unsigned int len, int compat)
+static int do_add_counters(struct net *net, void __user *user, unsigned int len,
+                          int compat)
 {
        unsigned int i;
        struct xt_counters_info tmp;
@@ -1132,7 +1133,7 @@ static int do_add_counters(void __user *user, unsigned int len, int compat)
                goto free;
        }
 
-       t = xt_find_table_lock(NF_ARP, name);
+       t = xt_find_table_lock(net, NF_ARP, name);
        if (!t || IS_ERR(t)) {
                ret = t ? PTR_ERR(t) : -ENOENT;
                goto free;
@@ -1435,7 +1436,8 @@ struct compat_arpt_replace {
        struct compat_arpt_entry        entries[0];
 };
 
-static int compat_do_replace(void __user *user, unsigned int len)
+static int compat_do_replace(struct net *net, void __user *user,
+                            unsigned int len)
 {
        int ret;
        struct compat_arpt_replace tmp;
@@ -1471,7 +1473,7 @@ static int compat_do_replace(void __user *user, unsigned int len)
 
        duprintf("compat_do_replace: Translated table\n");
 
-       ret = __do_replace(tmp.name, tmp.valid_hooks, newinfo,
+       ret = __do_replace(net, tmp.name, tmp.valid_hooks, newinfo,
                           tmp.num_counters, compat_ptr(tmp.counters));
        if (ret)
                goto free_newinfo_untrans;
@@ -1494,11 +1496,11 @@ static int compat_do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user,
 
        switch (cmd) {
        case ARPT_SO_SET_REPLACE:
-               ret = compat_do_replace(user, len);
+               ret = compat_do_replace(sk->sk_net, user, len);
                break;
 
        case ARPT_SO_SET_ADD_COUNTERS:
-               ret = do_add_counters(user, len, 1);
+               ret = do_add_counters(sk->sk_net, user, len, 1);
                break;
 
        default:
@@ -1584,7 +1586,8 @@ struct compat_arpt_get_entries {
        struct compat_arpt_entry entrytable[0];
 };
 
-static int compat_get_entries(struct compat_arpt_get_entries __user *uptr,
+static int compat_get_entries(struct net *net,
+                             struct compat_arpt_get_entries __user *uptr,
                              int *len)
 {
        int ret;
@@ -1604,7 +1607,7 @@ static int compat_get_entries(struct compat_arpt_get_entries __user *uptr,
        }
 
        xt_compat_lock(NF_ARP);
-       t = xt_find_table_lock(NF_ARP, get.name);
+       t = xt_find_table_lock(net, NF_ARP, get.name);
        if (t && !IS_ERR(t)) {
                struct xt_table_info *private = t->private;
                struct xt_table_info info;
@@ -1641,10 +1644,10 @@ static int compat_do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user,
 
        switch (cmd) {
        case ARPT_SO_GET_INFO:
-               ret = get_info(user, len, 1);
+               ret = get_info(sk->sk_net, user, len, 1);
                break;
        case ARPT_SO_GET_ENTRIES:
-               ret = compat_get_entries(user, len);
+               ret = compat_get_entries(sk->sk_net, user, len);
                break;
        default:
                ret = do_arpt_get_ctl(sk, cmd, user, len);
@@ -1662,11 +1665,11 @@ static int do_arpt_set_ctl(struct sock *sk, int cmd, void __user *user, unsigned
 
        switch (cmd) {
        case ARPT_SO_SET_REPLACE:
-               ret = do_replace(user, len);
+               ret = do_replace(sk->sk_net, user, len);
                break;
 
        case ARPT_SO_SET_ADD_COUNTERS:
-               ret = do_add_counters(user, len, 0);
+               ret = do_add_counters(sk->sk_net, user, len, 0);
                break;
 
        default:
@@ -1686,11 +1689,11 @@ static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len
 
        switch (cmd) {
        case ARPT_SO_GET_INFO:
-               ret = get_info(user, len, 0);
+               ret = get_info(sk->sk_net, user, len, 0);
                break;
 
        case ARPT_SO_GET_ENTRIES:
-               ret = get_entries(user, len);
+               ret = get_entries(sk->sk_net, user, len);
                break;
 
        case ARPT_SO_GET_REVISION_TARGET: {
@@ -1719,8 +1722,9 @@ static int do_arpt_get_ctl(struct sock *sk, int cmd, void __user *user, int *len
        return ret;
 }
 
-int arpt_register_table(struct arpt_table *table,
-                       const struct arpt_replace *repl)
+struct arpt_table *arpt_register_table(struct net *net,
+                                      struct arpt_table *table,
+                                      const struct arpt_replace *repl)
 {
        int ret;
        struct xt_table_info *newinfo;
@@ -1732,7 +1736,7 @@ int arpt_register_table(struct arpt_table *table,
        newinfo = xt_alloc_table_info(repl->size);
        if (!newinfo) {
                ret = -ENOMEM;
-               return ret;
+               goto out;
        }
 
        /* choose the copy on our node/cpu */
@@ -1746,24 +1750,27 @@ int arpt_register_table(struct arpt_table *table,
                              repl->underflow);
 
        duprintf("arpt_register_table: translate table gives %d\n", ret);
-       if (ret != 0) {
-               xt_free_table_info(newinfo);
-               return ret;
-       }
+       if (ret != 0)
+               goto out_free;
 
-       new_table = xt_register_table(table, &bootstrap, newinfo);
+       new_table = xt_register_table(net, table, &bootstrap, newinfo);
        if (IS_ERR(new_table)) {
-               xt_free_table_info(newinfo);
-               return PTR_ERR(new_table);
+               ret = PTR_ERR(new_table);
+               goto out_free;
        }
+       return new_table;
 
-       return 0;
+out_free:
+       xt_free_table_info(newinfo);
+out:
+       return ERR_PTR(ret);
 }
 
 void arpt_unregister_table(struct arpt_table *table)
 {
        struct xt_table_info *private;
        void *loc_cpu_entry;
+       struct module *table_owner = table->me;
 
        private = xt_unregister_table(table);
 
@@ -1771,6 +1778,8 @@ void arpt_unregister_table(struct arpt_table *table)
        loc_cpu_entry = private->entries[raw_smp_processor_id()];
        ARPT_ENTRY_ITERATE(loc_cpu_entry, private->size,
                           cleanup_entry, NULL);
+       if (private->number > private->initial_entries)
+               module_put(table_owner);
        xt_free_table_info(private);
 }
 
@@ -1810,11 +1819,26 @@ static struct nf_sockopt_ops arpt_sockopts = {
        .owner          = THIS_MODULE,
 };
 
+static int __net_init arp_tables_net_init(struct net *net)
+{
+       return xt_proto_init(net, NF_ARP);
+}
+
+static void __net_exit arp_tables_net_exit(struct net *net)
+{
+       xt_proto_fini(net, NF_ARP);
+}
+
+static struct pernet_operations arp_tables_net_ops = {
+       .init = arp_tables_net_init,
+       .exit = arp_tables_net_exit,
+};
+
 static int __init arp_tables_init(void)
 {
        int ret;
 
-       ret = xt_proto_init(NF_ARP);
+       ret = register_pernet_subsys(&arp_tables_net_ops);
        if (ret < 0)
                goto err1;
 
@@ -1839,7 +1863,7 @@ err4:
 err3:
        xt_unregister_target(&arpt_standard_target);
 err2:
-       xt_proto_fini(NF_ARP);
+       unregister_pernet_subsys(&arp_tables_net_ops);
 err1:
        return ret;
 }
@@ -1849,7 +1873,7 @@ static void __exit arp_tables_fini(void)
        nf_unregister_sockopt(&arpt_sockopts);
        xt_unregister_target(&arpt_error_target);
        xt_unregister_target(&arpt_standard_target);
-       xt_proto_fini(NF_ARP);
+       unregister_pernet_subsys(&arp_tables_net_ops);
 }
 
 EXPORT_SYMBOL(arpt_register_table);