netfilter: ebtables: do centralized size checking

[safe/jmp/linux-2.6] / net / bridge / netfilter / ebt_802_3.c

diff --git a/net/bridge/netfilter/ebt_802_3.c b/net/bridge/netfilter/ebt_802_3.c
index 9abbc09..ccecfbd 100644 (file)
--- a/net/bridge/netfilter/ebt_802_3.c
+++ b/net/bridge/netfilter/ebt_802_3.c
@@ -5,22 +5,22 @@
  * Chris Vitale csv@bluetail.com
  *
  * May 2003
- * 
+ *
  */
-
+#include <linux/module.h>
+#include <linux/netfilter/x_tables.h>
 #include <linux/netfilter_bridge/ebtables.h>
 #include <linux/netfilter_bridge/ebt_802_3.h>
-#include <linux/module.h>
 
 static int ebt_filter_802_3(const struct sk_buff *skb, const struct net_device *in,
    const struct net_device *out, const void *data, unsigned int datalen)
 {
-       struct ebt_802_3_info *info = (struct ebt_802_3_info *)data;
-       struct ebt_802_3_hdr *hdr = ebt_802_3_hdr(skb);
+       const struct ebt_802_3_info *info = data;
+       const struct ebt_802_3_hdr *hdr = ebt_802_3_hdr(skb);
        __be16 type = hdr->llc.ui.ctrl & IS_UI ? hdr->llc.ui.type : hdr->llc.ni.type;
 
        if (info->bitmask & EBT_802_3_SAP) {
-               if (FWINV(info->sap != hdr->llc.ui.ssap, EBT_802_3_SAP)) 
+               if (FWINV(info->sap != hdr->llc.ui.ssap, EBT_802_3_SAP))
                                return EBT_NOMATCH;
                if (FWINV(info->sap != hdr->llc.ui.dsap, EBT_802_3_SAP))
                                return EBT_NOMATCH;
@@ -29,7 +29,7 @@ static int ebt_filter_802_3(const struct sk_buff *skb, const struct net_device *
        if (info->bitmask & EBT_802_3_TYPE) {
                if (!(hdr->llc.ui.dsap == CHECK_TYPE && hdr->llc.ui.ssap == CHECK_TYPE))
                        return EBT_NOMATCH;
-               if (FWINV(info->type != type, EBT_802_3_TYPE)) 
+               if (FWINV(info->type != type, EBT_802_3_TYPE))
                        return EBT_NOMATCH;
        }
 
@@ -40,21 +40,19 @@ static struct ebt_match filter_802_3;
 static int ebt_802_3_check(const char *tablename, unsigned int hookmask,
    const struct ebt_entry *e, void *data, unsigned int datalen)
 {
-       struct ebt_802_3_info *info = (struct ebt_802_3_info *)data;
+       const struct ebt_802_3_info *info = data;
 
-       if (datalen < sizeof(struct ebt_802_3_info))
-               return -EINVAL;
        if (info->bitmask & ~EBT_802_3_MASK || info->invflags & ~EBT_802_3_MASK)
                return -EINVAL;
 
        return 0;
 }
 
-static struct ebt_match filter_802_3 =
-{
+static struct ebt_match filter_802_3 __read_mostly = {
        .name           = EBT_802_3_MATCH,
        .match          = ebt_filter_802_3,
        .check          = ebt_802_3_check,
+       .matchsize      = XT_ALIGN(sizeof(struct ebt_802_3_info)),
        .me             = THIS_MODULE,
 };
 
@@ -70,4 +68,5 @@ static void __exit ebt_802_3_fini(void)
 
 module_init(ebt_802_3_init);
 module_exit(ebt_802_3_fini);
+MODULE_DESCRIPTION("Ebtables: DSAP/SSAP field and SNAP type matching");
 MODULE_LICENSE("GPL");