net/ipv4: VTI support rx-path hook in xfrm4_mode_tunnel.

Incorporated David and Steffen's comments.
Add hook for rx-path xfmr4_mode_tunnel for VTI tunnel module.

Signed-off-by: Saurabh Mohan <saurabh.mohan@vyatta.com>
Reviewed-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Saurabh 2012-07-17 09:44:49 +00:00 committed by David S. Miller
parent fcc24db5e8
commit eb8637cd4a
2 changed files with 70 additions and 0 deletions

View File

@ -1475,6 +1475,8 @@ extern int xfrm4_output(struct sk_buff *skb);
extern int xfrm4_output_finish(struct sk_buff *skb);
extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family);
extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family);
extern int xfrm4_mode_tunnel_input_register(struct xfrm_tunnel *handler);
extern int xfrm4_mode_tunnel_input_deregister(struct xfrm_tunnel *handler);
extern int xfrm6_extract_header(struct sk_buff *skb);
extern int xfrm6_extract_input(struct xfrm_state *x, struct sk_buff *skb);
extern int xfrm6_rcv_spi(struct sk_buff *skb, int nexthdr, __be32 spi);

View File

@ -15,6 +15,65 @@
#include <net/ip.h>
#include <net/xfrm.h>
/* Informational hook. The decap is still done here. */
static struct xfrm_tunnel __rcu *rcv_notify_handlers __read_mostly;
static DEFINE_MUTEX(xfrm4_mode_tunnel_input_mutex);
int xfrm4_mode_tunnel_input_register(struct xfrm_tunnel *handler)
{
struct xfrm_tunnel __rcu **pprev;
struct xfrm_tunnel *t;
int ret = -EEXIST;
int priority = handler->priority;
mutex_lock(&xfrm4_mode_tunnel_input_mutex);
for (pprev = &rcv_notify_handlers;
(t = rcu_dereference_protected(*pprev,
lockdep_is_held(&xfrm4_mode_tunnel_input_mutex))) != NULL;
pprev = &t->next) {
if (t->priority > priority)
break;
if (t->priority == priority)
goto err;
}
handler->next = *pprev;
rcu_assign_pointer(*pprev, handler);
ret = 0;
err:
mutex_unlock(&xfrm4_mode_tunnel_input_mutex);
return ret;
}
EXPORT_SYMBOL_GPL(xfrm4_mode_tunnel_input_register);
int xfrm4_mode_tunnel_input_deregister(struct xfrm_tunnel *handler)
{
struct xfrm_tunnel __rcu **pprev;
struct xfrm_tunnel *t;
int ret = -ENOENT;
mutex_lock(&xfrm4_mode_tunnel_input_mutex);
for (pprev = &rcv_notify_handlers;
(t = rcu_dereference_protected(*pprev,
lockdep_is_held(&xfrm4_mode_tunnel_input_mutex))) != NULL;
pprev = &t->next) {
if (t == handler) {
*pprev = handler->next;
ret = 0;
break;
}
}
mutex_unlock(&xfrm4_mode_tunnel_input_mutex);
synchronize_net();
return ret;
}
EXPORT_SYMBOL_GPL(xfrm4_mode_tunnel_input_deregister);
static inline void ipip_ecn_decapsulate(struct sk_buff *skb)
{
struct iphdr *inner_iph = ipip_hdr(skb);
@ -64,8 +123,14 @@ static int xfrm4_mode_tunnel_output(struct xfrm_state *x, struct sk_buff *skb)
return 0;
}
#define for_each_input_rcu(head, handler) \
for (handler = rcu_dereference(head); \
handler != NULL; \
handler = rcu_dereference(handler->next))
static int xfrm4_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
{
struct xfrm_tunnel *handler;
int err = -EINVAL;
if (XFRM_MODE_SKB_CB(skb)->protocol != IPPROTO_IPIP)
@ -74,6 +139,9 @@ static int xfrm4_mode_tunnel_input(struct xfrm_state *x, struct sk_buff *skb)
if (!pskb_may_pull(skb, sizeof(struct iphdr)))
goto out;
for_each_input_rcu(rcv_notify_handlers, handler)
handler->handler(skb);
if (skb_cloned(skb) &&
(err = pskb_expand_head(skb, 0, 0, GFP_ATOMIC)))
goto out;