selinux: remove unneeded ipv6 hook wrappers

Netfilter places the protocol number the hook function is getting called
from in state->pf, so we can use that instead of an extra wrapper.

While at it, remove one-line wrappers too and make
selinux_ip_{out,forward,postroute} useable as hook function.
Signed-off-by: Florian Westphal <fw@strlen.de>
Message-Id: <20211011202229.28289-1-fw@strlen.de>
Signed-off-by: Paul Moore <paul@paul-moore.com>

security/selinux/hooks.c

@@ -5689,10 +5689,11 @@ static int selinux_tun_dev_open(void *security)
 
 #ifdef CONFIG_NETFILTER
 
-static unsigned int selinux_ip_forward(struct sk_buff *skb,
-				       const struct net_device *indev,
-				       u16 family)
+static unsigned int selinux_ip_forward(void *priv, struct sk_buff *skb,
+				       const struct nf_hook_state *state)
 {
+	const struct net_device *indev = state->in;
+	u16 family = state->pf;
 	int err;
 	char *addrp;
 	u32 peer_sid;
@@ -5747,25 +5748,10 @@ static unsigned int selinux_ip_forward(struct sk_buff *skb,
 	return NF_ACCEPT;
 }
 
-static unsigned int selinux_ipv4_forward(void *priv,
-					 struct sk_buff *skb,
+static unsigned int selinux_ip_output(void *priv, struct sk_buff *skb,
 				      const struct nf_hook_state *state)
 {
-	return selinux_ip_forward(skb, state->in, PF_INET);
-}
-
-#if IS_ENABLED(CONFIG_IPV6)
-static unsigned int selinux_ipv6_forward(void *priv,
-					 struct sk_buff *skb,
-					 const struct nf_hook_state *state)
-{
-	return selinux_ip_forward(skb, state->in, PF_INET6);
-}
-#endif	/* IPV6 */
-
-static unsigned int selinux_ip_output(struct sk_buff *skb,
-				      u16 family)
-{
+	u16 family = state->pf;
 	struct sock *sk;
 	u32 sid;
 
@@ -5805,21 +5791,6 @@ static unsigned int selinux_ip_output(struct sk_buff *skb,
 	return NF_ACCEPT;
 }
 
-static unsigned int selinux_ipv4_output(void *priv,
-					struct sk_buff *skb,
-					const struct nf_hook_state *state)
-{
-	return selinux_ip_output(skb, PF_INET);
-}
-
-#if IS_ENABLED(CONFIG_IPV6)
-static unsigned int selinux_ipv6_output(void *priv,
-					struct sk_buff *skb,
-					const struct nf_hook_state *state)
-{
-	return selinux_ip_output(skb, PF_INET6);
-}
-#endif	/* IPV6 */
 
 static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
 						int ifindex,
@@ -5855,10 +5826,12 @@ static unsigned int selinux_ip_postroute_compat(struct sk_buff *skb,
 	return NF_ACCEPT;
 }
 
-static unsigned int selinux_ip_postroute(struct sk_buff *skb,
-					 const struct net_device *outdev,
-					 u16 family)
+static unsigned int selinux_ip_postroute(void *priv,
+					 struct sk_buff *skb,
+					 const struct nf_hook_state *state)
 {
+	const struct net_device *outdev = state->out;
+	u16 family = state->pf;
 	u32 secmark_perm;
 	u32 peer_sid;
 	int ifindex = outdev->ifindex;
@@ -5994,23 +5967,6 @@ static unsigned int selinux_ip_postroute(struct sk_buff *skb,
 
 	return NF_ACCEPT;
 }
-
-static unsigned int selinux_ipv4_postroute(void *priv,
-					   struct sk_buff *skb,
-					   const struct nf_hook_state *state)
-{
-	return selinux_ip_postroute(skb, state->out, PF_INET);
-}
-
-#if IS_ENABLED(CONFIG_IPV6)
-static unsigned int selinux_ipv6_postroute(void *priv,
-					   struct sk_buff *skb,
-					   const struct nf_hook_state *state)
-{
-	return selinux_ip_postroute(skb, state->out, PF_INET6);
-}
-#endif	/* IPV6 */
-
 #endif	/* CONFIG_NETFILTER */
 
 static int selinux_netlink_send(struct sock *sk, struct sk_buff *skb)
@@ -7475,38 +7431,38 @@ DEFINE_LSM(selinux) = {
 
 static const struct nf_hook_ops selinux_nf_ops[] = {
 	{
-		.hook =		selinux_ipv4_postroute,
+		.hook =		selinux_ip_postroute,
 		.pf =		NFPROTO_IPV4,
 		.hooknum =	NF_INET_POST_ROUTING,
 		.priority =	NF_IP_PRI_SELINUX_LAST,
 	},
 	{
-		.hook =		selinux_ipv4_forward,
+		.hook =		selinux_ip_forward,
 		.pf =		NFPROTO_IPV4,
 		.hooknum =	NF_INET_FORWARD,
 		.priority =	NF_IP_PRI_SELINUX_FIRST,
 	},
 	{
-		.hook =		selinux_ipv4_output,
+		.hook =		selinux_ip_output,
 		.pf =		NFPROTO_IPV4,
 		.hooknum =	NF_INET_LOCAL_OUT,
 		.priority =	NF_IP_PRI_SELINUX_FIRST,
 	},
 #if IS_ENABLED(CONFIG_IPV6)
 	{
-		.hook =		selinux_ipv6_postroute,
+		.hook =		selinux_ip_postroute,
 		.pf =		NFPROTO_IPV6,
 		.hooknum =	NF_INET_POST_ROUTING,
 		.priority =	NF_IP6_PRI_SELINUX_LAST,
 	},
 	{
-		.hook =		selinux_ipv6_forward,
+		.hook =		selinux_ip_forward,
 		.pf =		NFPROTO_IPV6,
 		.hooknum =	NF_INET_FORWARD,
 		.priority =	NF_IP6_PRI_SELINUX_FIRST,
 	},
 	{
-		.hook =		selinux_ipv6_output,
+		.hook =		selinux_ip_output,
 		.pf =		NFPROTO_IPV6,
 		.hooknum =	NF_INET_LOCAL_OUT,
 		.priority =	NF_IP6_PRI_SELINUX_FIRST,