[XFRM]: Netfilter IPsec output hooks
Call netfilter hooks before IPsec transforms. Packets visit the
FORWARD/LOCAL_OUT and POST_ROUTING hook before the first encapsulation
and the LOCAL_OUT and POST_ROUTING hook before each following tunnel mode
transform.
Patch from Herbert Xu <herbert@gondor.apana.org.au>:
Move the loop from dst_output into xfrm4_output/xfrm6_output since they're
the only ones who need to it. xfrm{4,6}_output_one() processes the first SA
all subsequent transport mode SAs and is called in a loop that calls the
netfilter hooks between each two calls.
In order to avoid the tail call issue, I've added the inline function
nf_hook which is nf_hook_slow plus the empty list check.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/netfilter.h b/include/linux/netfilter.h
index be365e7..79bb977 100644
--- a/include/linux/netfilter.h
+++ b/include/linux/netfilter.h
@@ -168,6 +168,37 @@
const struct net_device *out,
struct nf_loginfo *li,
const char *fmt, ...);
+
+int nf_hook_slow(int pf, unsigned int hook, struct sk_buff **pskb,
+ struct net_device *indev, struct net_device *outdev,
+ int (*okfn)(struct sk_buff *), int thresh);
+
+/**
+ * nf_hook_thresh - call a netfilter hook
+ *
+ * Returns 1 if the hook has allowed the packet to pass. The function
+ * okfn must be invoked by the caller in this case. Any other return
+ * value indicates the packet has been consumed by the hook.
+ */
+static inline int nf_hook_thresh(int pf, unsigned int hook,
+ struct sk_buff **pskb,
+ struct net_device *indev,
+ struct net_device *outdev,
+ int (*okfn)(struct sk_buff *), int thresh)
+{
+#ifndef CONFIG_NETFILTER_DEBUG
+ if (list_empty(&nf_hooks[pf][hook]))
+ return 1;
+#endif
+ return nf_hook_slow(pf, hook, pskb, indev, outdev, okfn, thresh);
+}
+
+static inline int nf_hook(int pf, unsigned int hook, struct sk_buff **pskb,
+ struct net_device *indev, struct net_device *outdev,
+ int (*okfn)(struct sk_buff *))
+{
+ return nf_hook_thresh(pf, hook, pskb, indev, outdev, okfn, INT_MIN);
+}
/* Activate hook; either okfn or kfree_skb called, unless a hook
returns NF_STOLEN (in which case, it's up to the hook to deal with
@@ -188,35 +219,17 @@
/* This is gross, but inline doesn't cut it for avoiding the function
call in fast path: gcc doesn't inline (needs value tracking?). --RR */
-#ifdef CONFIG_NETFILTER_DEBUG
-#define NF_HOOK(pf, hook, skb, indev, outdev, okfn) \
-({int __ret; \
-if ((__ret=nf_hook_slow(pf, hook, &(skb), indev, outdev, okfn, INT_MIN)) == 1) \
- __ret = (okfn)(skb); \
-__ret;})
-#define NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, thresh) \
-({int __ret; \
-if ((__ret=nf_hook_slow(pf, hook, &(skb), indev, outdev, okfn, thresh)) == 1) \
- __ret = (okfn)(skb); \
-__ret;})
-#else
-#define NF_HOOK(pf, hook, skb, indev, outdev, okfn) \
-({int __ret; \
-if (list_empty(&nf_hooks[pf][hook]) || \
- (__ret=nf_hook_slow(pf, hook, &(skb), indev, outdev, okfn, INT_MIN)) == 1) \
- __ret = (okfn)(skb); \
-__ret;})
-#define NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, thresh) \
-({int __ret; \
-if (list_empty(&nf_hooks[pf][hook]) || \
- (__ret=nf_hook_slow(pf, hook, &(skb), indev, outdev, okfn, thresh)) == 1) \
- __ret = (okfn)(skb); \
-__ret;})
-#endif
-int nf_hook_slow(int pf, unsigned int hook, struct sk_buff **pskb,
- struct net_device *indev, struct net_device *outdev,
- int (*okfn)(struct sk_buff *), int thresh);
+/* HX: It's slightly less gross now. */
+
+#define NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, thresh) \
+({int __ret; \
+if ((__ret=nf_hook_thresh(pf, hook, &(skb), indev, outdev, okfn, thresh)) == 1)\
+ __ret = (okfn)(skb); \
+__ret;})
+
+#define NF_HOOK(pf, hook, skb, indev, outdev, okfn) \
+ NF_HOOK_THRESH(pf, hook, skb, indev, outdev, okfn, INT_MIN)
/* Call setsockopt() */
int nf_setsockopt(struct sock *sk, int pf, int optval, char __user *opt,