[NETFILTER]: Add address family specific checksum helpers

Add checksum operation which takes care of verifying the checksum and
dealing with HW checksum errors and avoids multiple checksum
operations by setting ip_summed to CHECKSUM_UNNECESSARY after
successful verification.

Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Patrick McHardy 2006-04-06 14:18:43 -07:00 committed by David S. Miller
parent bce8032ef3
commit 422c346fad
5 changed files with 89 additions and 0 deletions

View file

@ -285,6 +285,8 @@ extern int skb_make_writable(struct sk_buff **pskb, unsigned int writable_len);
struct nf_afinfo {
unsigned short family;
unsigned int (*checksum)(struct sk_buff *skb, unsigned int hook,
unsigned int dataoff, u_int8_t protocol);
void (*saveroute)(const struct sk_buff *skb,
struct nf_info *info);
int (*reroute)(struct sk_buff **skb,
@ -298,6 +300,21 @@ static inline struct nf_afinfo *nf_get_afinfo(unsigned short family)
return rcu_dereference(nf_afinfo[family]);
}
static inline unsigned int
nf_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff,
u_int8_t protocol, unsigned short family)
{
struct nf_afinfo *afinfo;
unsigned int csum = 0;
rcu_read_lock();
afinfo = nf_get_afinfo(family);
if (afinfo)
csum = afinfo->checksum(skb, hook, dataoff, protocol);
rcu_read_unlock();
return csum;
}
extern int nf_register_afinfo(struct nf_afinfo *afinfo);
extern void nf_unregister_afinfo(struct nf_afinfo *afinfo);

View file

@ -80,6 +80,8 @@ enum nf_ip_hook_priorities {
#ifdef __KERNEL__
extern int ip_route_me_harder(struct sk_buff **pskb);
extern int ip_xfrm_me_harder(struct sk_buff **pskb);
extern unsigned int nf_ip_checksum(struct sk_buff *skb, unsigned int hook,
unsigned int dataoff, u_int8_t protocol);
#endif /*__KERNEL__*/
#endif /*__LINUX_IP_NETFILTER_H*/

View file

@ -73,6 +73,9 @@ enum nf_ip6_hook_priorities {
};
#ifdef CONFIG_NETFILTER
extern unsigned int nf_ip6_checksum(struct sk_buff *skb, unsigned int hook,
unsigned int dataoff, u_int8_t protocol);
extern int ipv6_netfilter_init(void);
extern void ipv6_netfilter_fini(void);
#else /* CONFIG_NETFILTER */