[NETFILTER]: ip_tables: move compat offset calculation to x_tables

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

diff --git a/net/netfilter/x_tables.c b/net/netfilter/x_tables.c
index b95284e..8d4fca9 100644 (file)
--- a/net/netfilter/x_tables.c
+++ b/net/netfilter/x_tables.c
@@ -34,12 +34,21 @@ MODULE_DESCRIPTION("[ip,ip6,arp]_tables backend module");
 
 #define SMP_ALIGN(x) (((x) + SMP_CACHE_BYTES-1) & ~(SMP_CACHE_BYTES-1))
 
+struct compat_delta {
+       struct compat_delta *next;
+       unsigned int offset;
+       short delta;
+};
+
 struct xt_af {
        struct mutex mutex;
        struct list_head match;
        struct list_head target;
        struct list_head tables;
+#ifdef CONFIG_COMPAT
        struct mutex compat_mutex;
+       struct compat_delta *compat_offsets;
+#endif
 };
 
 static struct xt_af *xt;
@@ -335,6 +344,54 @@ int xt_check_match(const struct xt_match *match, unsigned short family,
 EXPORT_SYMBOL_GPL(xt_check_match);
 
 #ifdef CONFIG_COMPAT
+int xt_compat_add_offset(int af, unsigned int offset, short delta)
+{
+       struct compat_delta *tmp;
+
+       tmp = kmalloc(sizeof(struct compat_delta), GFP_KERNEL);
+       if (!tmp)
+               return -ENOMEM;
+
+       tmp->offset = offset;
+       tmp->delta = delta;
+
+       if (xt[af].compat_offsets) {
+               tmp->next = xt[af].compat_offsets->next;
+               xt[af].compat_offsets->next = tmp;
+       } else {
+               xt[af].compat_offsets = tmp;
+               tmp->next = NULL;
+       }
+       return 0;
+}
+EXPORT_SYMBOL_GPL(xt_compat_add_offset);
+
+void xt_compat_flush_offsets(int af)
+{
+       struct compat_delta *tmp, *next;
+
+       if (xt[af].compat_offsets) {
+               for (tmp = xt[af].compat_offsets; tmp; tmp = next) {
+                       next = tmp->next;
+                       kfree(tmp);
+               }
+               xt[af].compat_offsets = NULL;
+       }
+}
+EXPORT_SYMBOL_GPL(xt_compat_flush_offsets);
+
+short xt_compat_calc_jump(int af, unsigned int offset)
+{
+       struct compat_delta *tmp;
+       short delta;
+
+       for (tmp = xt[af].compat_offsets, delta = 0; tmp; tmp = tmp->next)
+               if (tmp->offset < offset)
+                       delta += tmp->delta;
+       return delta;
+}
+EXPORT_SYMBOL_GPL(xt_compat_calc_jump);
+
 int xt_compat_match_offset(struct xt_match *match)
 {
        u_int16_t csize = match->compatsize ? : match->matchsize;
@@ -873,6 +930,7 @@ static int __init xt_init(void)
                mutex_init(&xt[i].mutex);
 #ifdef CONFIG_COMPAT
                mutex_init(&xt[i].compat_mutex);
+               xt[i].compat_offsets = NULL;
 #endif
                INIT_LIST_HEAD(&xt[i].target);
                INIT_LIST_HEAD(&xt[i].match);