[IPSEC]: Changing API of xfrm4_tunnel_register.

This patch changes xfrm4_tunnel register and deregister
interface to prepare for solving the conflict of device
tunnels with inter address family IPsec tunnel.

Signed-off-by: Kazunori MIYAZAWA <miyazawa@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

include/net/xfrm.h

@@ -946,8 +946,8 @@ extern int xfrm_state_mtu(struct xfrm_state *x, int mtu);
 extern int xfrm_init_state(struct xfrm_state *x);
 extern int xfrm4_rcv(struct sk_buff *skb);
 extern int xfrm4_output(struct sk_buff *skb);
-extern int xfrm4_tunnel_register(struct xfrm_tunnel *handler);
-extern int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler);
+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 xfrm6_rcv_spi(struct sk_buff *skb, __be32 spi);
 extern int xfrm6_rcv(struct sk_buff **pskb);
 extern int xfrm6_input_addr(struct sk_buff *skb, xfrm_address_t *daddr,

net/ipv4/ipip.c

@@ -871,7 +871,7 @@ static int __init ipip_init(void)
 
 	printk(banner);
 
-	if (xfrm4_tunnel_register(&ipip_handler)) {
+	if (xfrm4_tunnel_register(&ipip_handler, AF_INET)) {
 		printk(KERN_INFO "ipip init: can't register tunnel\n");
 		return -EAGAIN;
 	}
@@ -893,7 +893,7 @@ static int __init ipip_init(void)
  err2:
 	free_netdev(ipip_fb_tunnel_dev);
  err1:
-	xfrm4_tunnel_deregister(&ipip_handler);
+	xfrm4_tunnel_deregister(&ipip_handler, AF_INET);
 	goto out;
 }
 
@@ -913,7 +913,7 @@ static void __exit ipip_destroy_tunnels(void)
 
 static void __exit ipip_fini(void)
 {
-	if (xfrm4_tunnel_deregister(&ipip_handler))
+	if (xfrm4_tunnel_deregister(&ipip_handler, AF_INET))
 		printk(KERN_INFO "ipip close: can't deregister tunnel\n");
 
 	rtnl_lock();

net/ipv4/tunnel4.c

@@ -14,9 +14,10 @@
 #include <net/xfrm.h>
 
 static struct xfrm_tunnel *tunnel4_handlers;
+static struct xfrm_tunnel *tunnel64_handlers;
 static DEFINE_MUTEX(tunnel4_mutex);
 
-int xfrm4_tunnel_register(struct xfrm_tunnel *handler)
+int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family)
 {
 	struct xfrm_tunnel **pprev;
 	int ret = -EEXIST;
@@ -24,7 +25,8 @@ int xfrm4_tunnel_register(struct xfrm_tunnel *handler)
 
 	mutex_lock(&tunnel4_mutex);
 
-	for (pprev = &tunnel4_handlers; *pprev; pprev = &(*pprev)->next) {
+	for (pprev = (family == AF_INET) ? &tunnel4_handlers : &tunnel64_handlers;
+	     *pprev; pprev = &(*pprev)->next) {
 		if ((*pprev)->priority > priority)
 			break;
 		if ((*pprev)->priority == priority)
@@ -44,14 +46,15 @@ err:
 
 EXPORT_SYMBOL(xfrm4_tunnel_register);
 
-int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler)
+int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler, unsigned short family)
 {
 	struct xfrm_tunnel **pprev;
 	int ret = -ENOENT;
 
 	mutex_lock(&tunnel4_mutex);
 
-	for (pprev = &tunnel4_handlers; *pprev; pprev = &(*pprev)->next) {
+	for (pprev = (family == AF_INET) ? &tunnel4_handlers : &tunnel64_handlers;
+	     *pprev; pprev = &(*pprev)->next) {
 		if (*pprev == handler) {
 			*pprev = handler->next;
 			ret = 0;
@@ -86,6 +89,26 @@ drop:
 	return 0;
 }
 
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+static int tunnel64_rcv(struct sk_buff *skb)
+{
+	struct xfrm_tunnel *handler;
+
+	if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+		goto drop;
+
+	for (handler = tunnel64_handlers; handler; handler = handler->next)
+		if (!handler->handler(skb))
+			return 0;
+
+	icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
+
+drop:
+	kfree_skb(skb);
+	return 0;
+}
+#endif
+
 static void tunnel4_err(struct sk_buff *skb, u32 info)
 {
 	struct xfrm_tunnel *handler;
@@ -101,17 +124,36 @@ static struct net_protocol tunnel4_protocol = {
 	.no_policy	=	1,
 };
 
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+static struct net_protocol tunnel64_protocol = {
+	.handler	=	tunnel64_rcv,
+	.err_handler	=	tunnel4_err,
+	.no_policy	=	1,
+};
+#endif
+
 static int __init tunnel4_init(void)
 {
 	if (inet_add_protocol(&tunnel4_protocol, IPPROTO_IPIP)) {
 		printk(KERN_ERR "tunnel4 init: can't add protocol\n");
 		return -EAGAIN;
 	}
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+	if (inet_add_protocol(&tunnel64_protocol, IPPROTO_IPV6)) {
+		printk(KERN_ERR "tunnel64 init: can't add protocol\n");
+		inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP);
+		return -EAGAIN;
+	}
+#endif
 	return 0;
 }
 
 static void __exit tunnel4_fini(void)
 {
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+	if (inet_del_protocol(&tunnel64_protocol, IPPROTO_IPV6))
+		printk(KERN_ERR "tunnel64 close: can't remove protocol\n");
+#endif
 	if (inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP))
 		printk(KERN_ERR "tunnel4 close: can't remove protocol\n");
 }

net/ipv4/xfrm4_input.c

@@ -27,6 +27,7 @@ static int xfrm4_parse_spi(struct sk_buff *skb, u8 nexthdr, __be32 *spi, __be32
 {
 	switch (nexthdr) {
 	case IPPROTO_IPIP:
+	case IPPROTO_IPV6:
 		*spi = skb->nh.iph->saddr;
 		*seq = 0;
 		return 0;
@@ -70,7 +71,8 @@ int xfrm4_rcv_encap(struct sk_buff *skb, __u16 encap_type)
 		if (xfrm_nr == XFRM_MAX_DEPTH)
 			goto drop;
 
-		x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi, iph->protocol, AF_INET);
+		x = xfrm_state_lookup((xfrm_address_t *)&iph->daddr, spi,
+				iph->protocol != IPPROTO_IPV6 ? iph->protocol : IPPROTO_IPIP, AF_INET);
 		if (x == NULL)
 			goto drop;
 

net/ipv4/xfrm4_tunnel.c

@@ -64,24 +64,45 @@ static struct xfrm_tunnel xfrm_tunnel_handler = {
 	.priority	=	2,
 };
 
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+static struct xfrm_tunnel xfrm64_tunnel_handler = {
+	.handler	=	xfrm4_rcv,
+	.err_handler	=	xfrm_tunnel_err,
+	.priority	=	2,
+};
+#endif
+
 static int __init ipip_init(void)
 {
 	if (xfrm_register_type(&ipip_type, AF_INET) < 0) {
 		printk(KERN_INFO "ipip init: can't add xfrm type\n");
 		return -EAGAIN;
 	}
-	if (xfrm4_tunnel_register(&xfrm_tunnel_handler)) {
-		printk(KERN_INFO "ipip init: can't add xfrm handler\n");
+
+	if (xfrm4_tunnel_register(&xfrm_tunnel_handler, AF_INET)) {
+		printk(KERN_INFO "ipip init: can't add xfrm handler for AF_INET\n");
+		xfrm_unregister_type(&ipip_type, AF_INET);
+		return -EAGAIN;
+	}
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+	if (xfrm4_tunnel_register(&xfrm64_tunnel_handler, AF_INET6)) {
+		printk(KERN_INFO "ipip init: can't add xfrm handler for AF_INET6\n");
+		xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET);
 		xfrm_unregister_type(&ipip_type, AF_INET);
 		return -EAGAIN;
 	}
+#endif
 	return 0;
 }
 
 static void __exit ipip_fini(void)
 {
-	if (xfrm4_tunnel_deregister(&xfrm_tunnel_handler))
-		printk(KERN_INFO "ipip close: can't remove xfrm handler\n");
+#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
+	if (xfrm4_tunnel_deregister(&xfrm64_tunnel_handler, AF_INET6))
+		printk(KERN_INFO "ipip close: can't remove xfrm handler for AF_INET6\n");
+#endif
+	if (xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET))
+		printk(KERN_INFO "ipip close: can't remove xfrm handler for AF_INET\n");
 	if (xfrm_unregister_type(&ipip_type, AF_INET) < 0)
 		printk(KERN_INFO "ipip close: can't remove xfrm type\n");
 }