12 files changed, 344 insertions, 247 deletions

diff --git a/include/net/xfrm.h b/include/net/xfrm.h
index 61b7504fc2ba..e100291e43f4 100644
--- a/include/net/xfrm.h
+++ b/include/net/xfrm.h
@@ -864,13 +864,19 @@ struct xfrm_algo_desc {
 /* XFRM tunnel handlers.  */
 struct xfrm_tunnel {
         int (*handler)(struct sk_buff *skb);
-        void (*err_handler)(struct sk_buff *skb, __u32 info);
+        int (*err_handler)(struct sk_buff *skb, __u32 info);
+
+        struct xfrm_tunnel *next;
+        int priority;
 };
 
 struct xfrm6_tunnel {
-        int (*handler)(struct sk_buff **pskb);
-        void (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
-                            int type, int code, int offset, __u32 info);
+        int (*handler)(struct sk_buff *skb);
+        int (*err_handler)(struct sk_buff *skb, struct inet6_skb_parm *opt,
+                           int type, int code, int offset, __u32 info);
+
+        struct xfrm6_tunnel *next;
+        int priority;
 };
 
 extern void xfrm_init(void);
@@ -906,7 +912,7 @@ 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 xfrm6_rcv_spi(struct sk_buff **pskb, u32 spi);
+extern int xfrm6_rcv_spi(struct sk_buff *skb, u32 spi);
 extern int xfrm6_rcv(struct sk_buff **pskb);
 extern int xfrm6_tunnel_register(struct xfrm6_tunnel *handler);
 extern int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler);
diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig
index 011cca7ae02b..e40f75322377 100644
--- a/net/ipv4/Kconfig
+++ b/net/ipv4/Kconfig
@@ -235,6 +235,7 @@ config IP_PNP_RARP
 #   bool '    IP: ARP support' CONFIG_IP_PNP_ARP                
 config NET_IPIP
         tristate "IP: tunneling"
+        select INET_TUNNEL
         ---help---
           Tunneling means encapsulating data of one protocol type within
           another protocol and sending it over a channel that understands the
@@ -395,7 +396,7 @@ config INET_ESP
 config INET_IPCOMP
         tristate "IP: IPComp transformation"
         select XFRM
-        select INET_TUNNEL
+        select INET_XFRM_TUNNEL
         select CRYPTO
         select CRYPTO_DEFLATE
         ---help---
@@ -404,14 +405,14 @@ config INET_IPCOMP
           
           If unsure, say Y.
 
+config INET_XFRM_TUNNEL
+        tristate
+        select INET_TUNNEL
+        default n
+
 config INET_TUNNEL
-        tristate "IP: tunnel transformation"
-        select XFRM
-        ---help---
-          Support for generic IP tunnel transformation, which is required by
-          the IP tunneling module as well as tunnel mode IPComp.
-          
-          If unsure, say Y.
+        tristate
+        default n
 
 config INET_DIAG
         tristate "INET: socket monitoring interface"
diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile
index 35e5f5999092..9ef50a0b9d2c 100644
--- a/net/ipv4/Makefile
+++ b/net/ipv4/Makefile
@@ -22,7 +22,8 @@ obj-$(CONFIG_SYN_COOKIES) += syncookies.o
 obj-$(CONFIG_INET_AH) += ah4.o
 obj-$(CONFIG_INET_ESP) += esp4.o
 obj-$(CONFIG_INET_IPCOMP) += ipcomp.o
-obj-$(CONFIG_INET_TUNNEL) += xfrm4_tunnel.o 
+obj-$(CONFIG_INET_XFRM_TUNNEL) += xfrm4_tunnel.o
+obj-$(CONFIG_INET_TUNNEL) += tunnel4.o
 obj-$(CONFIG_IP_PNP) += ipconfig.o
 obj-$(CONFIG_IP_ROUTE_MULTIPATH_RR) += multipath_rr.o
 obj-$(CONFIG_IP_ROUTE_MULTIPATH_RANDOM) += multipath_random.o
diff --git a/net/ipv4/ipip.c b/net/ipv4/ipip.c
index 03d13742a4b8..eef07b0916a3 100644
--- a/net/ipv4/ipip.c
+++ b/net/ipv4/ipip.c
@@ -114,7 +114,6 @@
 #include <net/sock.h>
 #include <net/ip.h>
 #include <net/icmp.h>
-#include <net/protocol.h>
 #include <net/ipip.h>
 #include <net/inet_ecn.h>
 #include <net/xfrm.h>
@@ -274,7 +273,7 @@ static void ipip_tunnel_uninit(struct net_device *dev)
         dev_put(dev);
 }
 
-static void ipip_err(struct sk_buff *skb, u32 info)
+static int ipip_err(struct sk_buff *skb, u32 info)
 {
 #ifndef I_WISH_WORLD_WERE_PERFECT
 
@@ -286,21 +285,22 @@ static void ipip_err(struct sk_buff *skb, u32 info)
         int type = skb->h.icmph->type;
         int code = skb->h.icmph->code;
         struct ip_tunnel *t;
+        int err;
 
         switch (type) {
         default:
         case ICMP_PARAMETERPROB:
-                return;
+                return 0;
 
         case ICMP_DEST_UNREACH:
                 switch (code) {
                 case ICMP_SR_FAILED:
                 case ICMP_PORT_UNREACH:
                         /* Impossible event. */
-                        return;
+                        return 0;
                 case ICMP_FRAG_NEEDED:
                         /* Soft state for pmtu is maintained by IP core. */
-                        return;
+                        return 0;
                 default:
                         /* All others are translated to HOST_UNREACH.
                            rfc2003 contains "deep thoughts" about NET_UNREACH,
@@ -311,14 +311,18 @@ static void ipip_err(struct sk_buff *skb, u32 info)
                 break;
         case ICMP_TIME_EXCEEDED:
                 if (code != ICMP_EXC_TTL)
-                        return;
+                        return 0;
                 break;
         }
 
+        err = -ENOENT;
+
         read_lock(&ipip_lock);
         t = ipip_tunnel_lookup(iph->daddr, iph->saddr);
         if (t == NULL || t->parms.iph.daddr == 0)
                 goto out;
+
+        err = 0;
         if (t->parms.iph.ttl == 0 && type == ICMP_TIME_EXCEEDED)
                 goto out;
 
@@ -329,7 +333,7 @@ static void ipip_err(struct sk_buff *skb, u32 info)
         t->err_time = jiffies;
 out:
         read_unlock(&ipip_lock);
-        return;
+        return err;
 #else
         struct iphdr *iph = (struct iphdr*)dp;
         int hlen = iph->ihl<<2;
@@ -344,15 +348,15 @@ out:
         struct rtable *rt;
 
         if (len < hlen + sizeof(struct iphdr))
-                return;
+                return 0;
         eiph = (struct iphdr*)(dp + hlen);
 
         switch (type) {
         default:
-                return;
+                return 0;
         case ICMP_PARAMETERPROB:
                 if (skb->h.icmph->un.gateway < hlen)
-                        return;
+                        return 0;
 
                 /* So... This guy found something strange INSIDE encapsulated
                    packet. Well, he is fool, but what can we do ?
@@ -366,16 +370,16 @@ out:
                 case ICMP_SR_FAILED:
                 case ICMP_PORT_UNREACH:
                         /* Impossible event. */
-                        return;
+                        return 0;
                 case ICMP_FRAG_NEEDED:
                         /* And it is the only really necessary thing :-) */
                         rel_info = ntohs(skb->h.icmph->un.frag.mtu);
                         if (rel_info < hlen+68)
-                                return;
+                                return 0;
                         rel_info -= hlen;
                         /* BSD 4.2 MORE DOES NOT EXIST IN NATURE. */
                         if (rel_info > ntohs(eiph->tot_len))
-                                return;
+                                return 0;
                         break;
                 default:
                         /* All others are translated to HOST_UNREACH.
@@ -389,14 +393,14 @@ out:
                 break;
         case ICMP_TIME_EXCEEDED:
                 if (code != ICMP_EXC_TTL)
-                        return;
+                        return 0;
                 break;
         }
 
         /* Prepare fake skb to feed it to icmp_send */
         skb2 = skb_clone(skb, GFP_ATOMIC);
         if (skb2 == NULL)
-                return;
+                return 0;
         dst_release(skb2->dst);
         skb2->dst = NULL;
         skb_pull(skb2, skb->data - (u8*)eiph);
@@ -409,7 +413,7 @@ out:
         fl.proto = IPPROTO_IPIP;
         if (ip_route_output_key(&rt, &key)) {
                 kfree_skb(skb2);
-                return;
+                return 0;
         }
         skb2->dev = rt->u.dst.dev;
 
@@ -424,14 +428,14 @@ out:
                     rt->u.dst.dev->type != ARPHRD_TUNNEL) {
                         ip_rt_put(rt);
                         kfree_skb(skb2);
-                        return;
+                        return 0;
                 }
         } else {
                 ip_rt_put(rt);
                 if (ip_route_input(skb2, eiph->daddr, eiph->saddr, eiph->tos, skb2->dev) ||
                     skb2->dst->dev->type != ARPHRD_TUNNEL) {
                         kfree_skb(skb2);
-                        return;
+                        return 0;
                 }
         }
 
@@ -439,7 +443,7 @@ out:
         if (type == ICMP_DEST_UNREACH && code == ICMP_FRAG_NEEDED) {
                 if (rel_info > dst_mtu(skb2->dst)) {
                         kfree_skb(skb2);
-                        return;
+                        return 0;
                 }
                 skb2->dst->ops->update_pmtu(skb2->dst, rel_info);
                 rel_info = htonl(rel_info);
@@ -453,7 +457,7 @@ out:
 
         icmp_send(skb2, rel_type, rel_code, rel_info);
         kfree_skb(skb2);
-        return;
+        return 0;
 #endif
 }
 
@@ -855,39 +859,12 @@ static int __init ipip_fb_tunnel_init(struct net_device *dev)
         return 0;
 }
 
-#ifdef CONFIG_INET_TUNNEL
 static struct xfrm_tunnel ipip_handler = {
         .handler        =       ipip_rcv,
         .err_handler    =       ipip_err,
+        .priority       =       1,
 };
 
-static inline int ipip_register(void)
-{
-        return xfrm4_tunnel_register(&ipip_handler);
-}
-
-static inline int ipip_unregister(void)
-{
-        return xfrm4_tunnel_deregister(&ipip_handler);
-}
-#else
-static struct net_protocol ipip_protocol = {
-        .handler        =       ipip_rcv,
-        .err_handler    =       ipip_err,
-        .no_policy      =       1,
-};
-
-static inline int ipip_register(void)
-{
-        return inet_add_protocol(&ipip_protocol, IPPROTO_IPIP);
-}
-
-static inline int ipip_unregister(void)
-{
-        return inet_del_protocol(&ipip_protocol, IPPROTO_IPIP);
-}
-#endif
-
 static char banner[] __initdata =
         KERN_INFO "IPv4 over IPv4 tunneling driver\n";
 
@@ -897,7 +874,7 @@ static int __init ipip_init(void)
 
         printk(banner);
 
-        if (ipip_register() < 0) {
+        if (xfrm4_tunnel_register(&ipip_handler)) {
                 printk(KERN_INFO "ipip init: can't register tunnel\n");
                 return -EAGAIN;
         }
@@ -919,7 +896,7 @@ static int __init ipip_init(void)
  err2:
         free_netdev(ipip_fb_tunnel_dev);
  err1:
-        ipip_unregister();
+        xfrm4_tunnel_deregister(&ipip_handler);
         goto out;
 }
 
@@ -939,7 +916,7 @@ static void __exit ipip_destroy_tunnels(void)
 
 static void __exit ipip_fini(void)
 {
-        if (ipip_unregister() < 0)
+        if (xfrm4_tunnel_deregister(&ipip_handler))
                 printk(KERN_INFO "ipip close: can't deregister tunnel\n");
 
         rtnl_lock();
diff --git a/net/ipv4/tunnel4.c b/net/ipv4/tunnel4.c
new file mode 100644
index 000000000000..0d7d386dac22
--- /dev/null
+++ b/net/ipv4/tunnel4.c
@@ -0,0 +1,113 @@
+/* tunnel4.c: Generic IP tunnel transformer.
+ *
+ * Copyright (C) 2003 David S. Miller (davem@redhat.com)
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/protocol.h>
+#include <net/xfrm.h>
+
+static struct xfrm_tunnel *tunnel4_handlers;
+static DEFINE_MUTEX(tunnel4_mutex);
+
+int xfrm4_tunnel_register(struct xfrm_tunnel *handler)
+{
+        struct xfrm_tunnel **pprev;
+        int ret = -EEXIST;
+        int priority = handler->priority;
+
+        mutex_lock(&tunnel4_mutex);
+
+        for (pprev = &tunnel4_handlers; *pprev; pprev = &(*pprev)->next) {
+                if ((*pprev)->priority > priority)
+                        break;
+                if ((*pprev)->priority == priority)
+                        goto err;
+        }
+
+        handler->next = *pprev;
+        *pprev = handler;
+
+        ret = 0;
+
+err:
+        mutex_unlock(&tunnel4_mutex);
+
+        return ret;
+}
+
+EXPORT_SYMBOL(xfrm4_tunnel_register);
+
+int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler)
+{
+        struct xfrm_tunnel **pprev;
+        int ret = -ENOENT;
+
+        mutex_lock(&tunnel4_mutex);
+
+        for (pprev = &tunnel4_handlers; *pprev; pprev = &(*pprev)->next) {
+                if (*pprev == handler) {
+                        *pprev = handler->next;
+                        ret = 0;
+                        break;
+                }
+        }
+
+        mutex_unlock(&tunnel4_mutex);
+
+        synchronize_net();
+
+        return ret;
+}
+
+EXPORT_SYMBOL(xfrm4_tunnel_deregister);
+
+static int tunnel4_rcv(struct sk_buff *skb)
+{
+        struct xfrm_tunnel *handler;
+
+        for (handler = tunnel4_handlers; handler; handler = handler->next)
+                if (!handler->handler(skb))
+                        return 0;
+
+        kfree_skb(skb);
+        return 0;
+}
+
+static void tunnel4_err(struct sk_buff *skb, u32 info)
+{
+        struct xfrm_tunnel *handler;
+
+        for (handler = tunnel4_handlers; handler; handler = handler->next)
+                if (!handler->err_handler(skb, info))
+                        break;
+}
+
+static struct net_protocol tunnel4_protocol = {
+        .handler        =       tunnel4_rcv,
+        .err_handler    =       tunnel4_err,
+        .no_policy      =       1,
+};
+
+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;
+        }
+        return 0;
+}
+
+static void __exit tunnel4_fini(void)
+{
+        if (inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP))
+                printk(KERN_ERR "tunnel4 close: can't remove protocol\n");
+}
+
+module_init(tunnel4_init);
+module_exit(tunnel4_fini);
+MODULE_LICENSE("GPL");
diff --git a/net/ipv4/xfrm4_tunnel.c b/net/ipv4/xfrm4_tunnel.c
index b08d56b117f8..2d670935c2b5 100644
--- a/net/ipv4/xfrm4_tunnel.c
+++ b/net/ipv4/xfrm4_tunnel.c
@@ -26,64 +26,6 @@ static int ipip_xfrm_rcv(struct xfrm_state *x, struct xfrm_decap_state *decap, s
         return 0;
 }
 
-static struct xfrm_tunnel *ipip_handler;
-static DEFINE_MUTEX(xfrm4_tunnel_mutex);
-
-int xfrm4_tunnel_register(struct xfrm_tunnel *handler)
-{
-        int ret;
-
-        mutex_lock(&xfrm4_tunnel_mutex);
-        ret = 0;
-        if (ipip_handler != NULL)
-                ret = -EINVAL;
-        if (!ret)
-                ipip_handler = handler;
-        mutex_unlock(&xfrm4_tunnel_mutex);
-
-        return ret;
-}
-
-EXPORT_SYMBOL(xfrm4_tunnel_register);
-
-int xfrm4_tunnel_deregister(struct xfrm_tunnel *handler)
-{
-        int ret;
-
-        mutex_lock(&xfrm4_tunnel_mutex);
-        ret = 0;
-        if (ipip_handler != handler)
-                ret = -EINVAL;
-        if (!ret)
-                ipip_handler = NULL;
-        mutex_unlock(&xfrm4_tunnel_mutex);
-
-        synchronize_net();
-
-        return ret;
-}
-
-EXPORT_SYMBOL(xfrm4_tunnel_deregister);
-
-static int ipip_rcv(struct sk_buff *skb)
-{
-        struct xfrm_tunnel *handler = ipip_handler;
-
-        /* Tunnel devices take precedence.  */
-        if (handler && handler->handler(skb) == 0)
-                return 0;
-
-        return xfrm4_rcv(skb);
-}
-
-static void ipip_err(struct sk_buff *skb, u32 info)
-{
-        struct xfrm_tunnel *handler = ipip_handler;
-
-        if (handler)
-                handler->err_handler(skb, info);
-}
-
 static int ipip_init_state(struct xfrm_state *x)
 {
         if (!x->props.mode)
@@ -111,10 +53,15 @@ static struct xfrm_type ipip_type = {
         .output         = ipip_output
 };
 
-static struct net_protocol ipip_protocol = {
-        .handler        =       ipip_rcv,
-        .err_handler    =       ipip_err,
-        .no_policy      =       1,
+static int xfrm_tunnel_err(struct sk_buff *skb, u32 info)
+{
+        return -ENOENT;
+}
+
+static struct xfrm_tunnel xfrm_tunnel_handler = {
+        .handler        =       xfrm4_rcv,
+        .err_handler    =       xfrm_tunnel_err,
+        .priority       =       2,
 };
 
 static int __init ipip_init(void)
@@ -123,8 +70,8 @@ static int __init ipip_init(void)
                 printk(KERN_INFO "ipip init: can't add xfrm type\n");
                 return -EAGAIN;
         }
-        if (inet_add_protocol(&ipip_protocol, IPPROTO_IPIP) < 0) {
-                printk(KERN_INFO "ipip init: can't add protocol\n");
+        if (xfrm4_tunnel_register(&xfrm_tunnel_handler)) {
+                printk(KERN_INFO "ipip init: can't add xfrm handler\n");
                 xfrm_unregister_type(&ipip_type, AF_INET);
                 return -EAGAIN;
         }
@@ -133,8 +80,8 @@ static int __init ipip_init(void)
 
 static void __exit ipip_fini(void)
 {
-        if (inet_del_protocol(&ipip_protocol, IPPROTO_IPIP) < 0)
-                printk(KERN_INFO "ipip close: can't remove protocol\n");
+        if (xfrm4_tunnel_deregister(&xfrm_tunnel_handler))
+                printk(KERN_INFO "ipip close: can't remove xfrm handler\n");
         if (xfrm_unregister_type(&ipip_type, AF_INET) < 0)
                 printk(KERN_INFO "ipip close: can't remove xfrm type\n");
 }
diff --git a/net/ipv6/Kconfig b/net/ipv6/Kconfig
index e6f83b6a2b76..f8a107ab5592 100644
--- a/net/ipv6/Kconfig
+++ b/net/ipv6/Kconfig
@@ -88,7 +88,7 @@ config INET6_IPCOMP
         tristate "IPv6: IPComp transformation"
         depends on IPV6
         select XFRM
-        select INET6_TUNNEL
+        select INET6_XFRM_TUNNEL
         select CRYPTO
         select CRYPTO_DEFLATE
         ---help---
@@ -97,19 +97,18 @@ config INET6_IPCOMP
 
           If unsure, say Y.
 
+config INET6_XFRM_TUNNEL
+        tristate
+        select INET6_TUNNEL
+        default n
+
 config INET6_TUNNEL
-        tristate "IPv6: tunnel transformation"
-        depends on IPV6
-        select XFRM
-        ---help---
-          Support for generic IPv6-in-IPv6 tunnel transformation, which is
-          required by the IPv6-in-IPv6 tunneling module as well as tunnel mode
-          IPComp.
-          
-          If unsure, say Y.
+        tristate
+        default n
 
 config IPV6_TUNNEL
         tristate "IPv6: IPv6-in-IPv6 tunnel"
+        select INET6_TUNNEL
         depends on IPV6
         ---help---
           Support for IPv6-in-IPv6 tunnels described in RFC 2473.
diff --git a/net/ipv6/Makefile b/net/ipv6/Makefile
index 41877abd22e6..a760b0988fbb 100644
--- a/net/ipv6/Makefile
+++ b/net/ipv6/Makefile
@@ -18,7 +18,8 @@ ipv6-objs += $(ipv6-y)
 obj-$(CONFIG_INET6_AH) += ah6.o
 obj-$(CONFIG_INET6_ESP) += esp6.o
 obj-$(CONFIG_INET6_IPCOMP) += ipcomp6.o
-obj-$(CONFIG_INET6_TUNNEL) += xfrm6_tunnel.o 
+obj-$(CONFIG_INET6_XFRM_TUNNEL) += xfrm6_tunnel.o
+obj-$(CONFIG_INET6_TUNNEL) += tunnel6.o
 obj-$(CONFIG_NETFILTER) += netfilter/
 
 obj-$(CONFIG_IPV6_TUNNEL) += ip6_tunnel.o
diff --git a/net/ipv6/ip6_tunnel.c b/net/ipv6/ip6_tunnel.c
index 48597538db3f..ff9040c92556 100644
--- a/net/ipv6/ip6_tunnel.c
+++ b/net/ipv6/ip6_tunnel.c
@@ -44,7 +44,6 @@
 
 #include <net/ip.h>
 #include <net/ipv6.h>
-#include <net/protocol.h>
 #include <net/ip6_route.h>
 #include <net/addrconf.h>
 #include <net/ip6_tunnel.h>
@@ -391,7 +390,7 @@ parse_tlv_tnl_enc_lim(struct sk_buff *skb, __u8 * raw)
  *   to the specifications in RFC 2473.
  **/
 
-static void 
+static int
 ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
            int type, int code, int offset, __u32 info)
 {
@@ -402,6 +401,7 @@ ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
         int rel_code = ICMPV6_ADDR_UNREACH;
         __u32 rel_info = 0;
         __u16 len;
+        int err = -ENOENT;
 
         /* If the packet doesn't contain the original IPv6 header we are 
            in trouble since we might need the source address for further 
@@ -411,6 +411,8 @@ ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
         if ((t = ip6ip6_tnl_lookup(&ipv6h->daddr, &ipv6h->saddr)) == NULL)
                 goto out;
 
+        err = 0;
+
         switch (type) {
                 __u32 teli;
                 struct ipv6_tlv_tnl_enc_lim *tel;
@@ -492,6 +494,7 @@ ip6ip6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
         }
 out:
         read_unlock(&ip6ip6_lock);
+        return err;
 }
 
 static inline void ip6ip6_ecn_decapsulate(struct ipv6hdr *outer_iph,
@@ -511,9 +514,8 @@ static inline void ip6ip6_ecn_decapsulate(struct ipv6hdr *outer_iph,
  **/
 
 static int 
-ip6ip6_rcv(struct sk_buff **pskb)
+ip6ip6_rcv(struct sk_buff *skb)
 {
-        struct sk_buff *skb = *pskb;
         struct ipv6hdr *ipv6h;
         struct ip6_tnl *t;
 
@@ -1112,39 +1114,12 @@ ip6ip6_fb_tnl_dev_init(struct net_device *dev)
         return 0;
 }
 
-#ifdef CONFIG_INET6_TUNNEL
 static struct xfrm6_tunnel ip6ip6_handler = {
         .handler        = ip6ip6_rcv,
         .err_handler    = ip6ip6_err,
+        .priority       =       1,
 };
 
-static inline int ip6ip6_register(void)
-{
-        return xfrm6_tunnel_register(&ip6ip6_handler);
-}
-
-static inline int ip6ip6_unregister(void)
-{
-        return xfrm6_tunnel_deregister(&ip6ip6_handler);
-}
-#else
-static struct inet6_protocol xfrm6_tunnel_protocol = {
-        .handler        = ip6ip6_rcv,
-        .err_handler    = ip6ip6_err,
-        .flags          = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
-};
-
-static inline int ip6ip6_register(void)
-{
-        return inet6_add_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6);
-}
-
-static inline int ip6ip6_unregister(void)
-{
-        return inet6_del_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6);
-}
-#endif
-
 /**
  * ip6_tunnel_init - register protocol and reserve needed resources
  *
@@ -1155,7 +1130,7 @@ static int __init ip6_tunnel_init(void)
 {
         int  err;
 
-        if (ip6ip6_register() < 0) {
+        if (xfrm6_tunnel_register(&ip6ip6_handler)) {
                 printk(KERN_ERR "ip6ip6 init: can't register tunnel\n");
                 return -EAGAIN;
         }
@@ -1174,7 +1149,7 @@ static int __init ip6_tunnel_init(void)
         }
         return 0;
 fail:
-        ip6ip6_unregister();
+        xfrm6_tunnel_deregister(&ip6ip6_handler);
         return err;
 }
 
@@ -1184,7 +1159,7 @@ fail:
 
 static void __exit ip6_tunnel_cleanup(void)
 {
-        if (ip6ip6_unregister() < 0)
+        if (xfrm6_tunnel_deregister(&ip6ip6_handler))
                 printk(KERN_INFO "ip6ip6 close: can't deregister tunnel\n");
 
         unregister_netdev(ip6ip6_fb_tnl_dev);
diff --git a/net/ipv6/tunnel6.c b/net/ipv6/tunnel6.c
new file mode 100644
index 000000000000..5659b52284bd
--- /dev/null
+++ b/net/ipv6/tunnel6.c
@@ -0,0 +1,131 @@
+/*
+ * Copyright (C)2003,2004 USAGI/WIDE Project
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ *
+ * Authors      Mitsuru KANDA  <mk@linux-ipv6.org>
+ *              YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
+ */
+
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/netdevice.h>
+#include <linux/skbuff.h>
+#include <net/protocol.h>
+#include <net/xfrm.h>
+
+static struct xfrm6_tunnel *tunnel6_handlers;
+static DEFINE_MUTEX(tunnel6_mutex);
+
+int xfrm6_tunnel_register(struct xfrm6_tunnel *handler)
+{
+        struct xfrm6_tunnel **pprev;
+        int ret = -EEXIST;
+        int priority = handler->priority;
+
+        mutex_lock(&tunnel6_mutex);
+
+        for (pprev = &tunnel6_handlers; *pprev; pprev = &(*pprev)->next) {
+                if ((*pprev)->priority > priority)
+                        break;
+                if ((*pprev)->priority == priority)
+                        goto err;
+        }
+
+        handler->next = *pprev;
+        *pprev = handler;
+
+        ret = 0;
+
+err:
+        mutex_unlock(&tunnel6_mutex);
+
+        return ret;
+}
+
+EXPORT_SYMBOL(xfrm6_tunnel_register);
+
+int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler)
+{
+        struct xfrm6_tunnel **pprev;
+        int ret = -ENOENT;
+
+        mutex_lock(&tunnel6_mutex);
+
+        for (pprev = &tunnel6_handlers; *pprev; pprev = &(*pprev)->next) {
+                if (*pprev == handler) {
+                        *pprev = handler->next;
+                        ret = 0;
+                        break;
+                }
+        }
+
+        mutex_unlock(&tunnel6_mutex);
+
+        synchronize_net();
+
+        return ret;
+}
+
+EXPORT_SYMBOL(xfrm6_tunnel_deregister);
+
+static int tunnel6_rcv(struct sk_buff **pskb)
+{
+        struct sk_buff *skb = *pskb;
+        struct xfrm6_tunnel *handler;
+
+        for (handler = tunnel6_handlers; handler; handler = handler->next)
+                if (!handler->handler(skb))
+                        return 0;
+
+        kfree_skb(skb);
+        return 0;
+}
+
+static void tunnel6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
+                        int type, int code, int offset, __u32 info)
+{
+        struct xfrm6_tunnel *handler;
+
+        for (handler = tunnel6_handlers; handler; handler = handler->next)
+                if (!handler->err_handler(skb, opt, type, code, offset, info))
+                        break;
+}
+
+static struct inet6_protocol tunnel6_protocol = {
+        .handler        = tunnel6_rcv,
+        .err_handler    = tunnel6_err,
+        .flags          = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
+};
+
+static int __init tunnel6_init(void)
+{
+        if (inet6_add_protocol(&tunnel6_protocol, IPPROTO_IPV6)) {
+                printk(KERN_ERR "tunnel6 init(): can't add protocol\n");
+                return -EAGAIN;
+        }
+        return 0;
+}
+
+static void __exit tunnel6_fini(void)
+{
+        if (inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6))
+                printk(KERN_ERR "tunnel6 close: can't remove protocol\n");
+}
+
+module_init(tunnel6_init);
+module_exit(tunnel6_fini);
+MODULE_LICENSE("GPL");
diff --git a/net/ipv6/xfrm6_input.c b/net/ipv6/xfrm6_input.c
index 1ca2da68ef69..cccf8b76f046 100644
--- a/net/ipv6/xfrm6_input.c
+++ b/net/ipv6/xfrm6_input.c
@@ -28,9 +28,8 @@ static inline void ipip6_ecn_decapsulate(struct sk_buff *skb)
                 IP6_ECN_set_ce(inner_iph);
 }
 
-int xfrm6_rcv_spi(struct sk_buff **pskb, u32 spi)
+int xfrm6_rcv_spi(struct sk_buff *skb, u32 spi)
 {
-        struct sk_buff *skb = *pskb;
         int err;
         u32 seq;
         struct sec_decap_state xfrm_vec[XFRM_MAX_DEPTH];
@@ -159,5 +158,5 @@ EXPORT_SYMBOL(xfrm6_rcv_spi);
 
 int xfrm6_rcv(struct sk_buff **pskb)
 {
-        return xfrm6_rcv_spi(pskb, 0);
+        return xfrm6_rcv_spi(*pskb, 0);
 }
diff --git a/net/ipv6/xfrm6_tunnel.c b/net/ipv6/xfrm6_tunnel.c
index 08f9abbdf1d7..a8f6776c518d 100644
--- a/net/ipv6/xfrm6_tunnel.c
+++ b/net/ipv6/xfrm6_tunnel.c
@@ -28,7 +28,6 @@
 #include <net/ip.h>
 #include <net/xfrm.h>
 #include <net/ipv6.h>
-#include <net/protocol.h>
 #include <linux/ipv6.h>
 #include <linux/icmpv6.h>
 #include <linux/mutex.h>
@@ -357,71 +356,18 @@ static int xfrm6_tunnel_input(struct xfrm_state *x, struct xfrm_decap_state *dec
         return 0;
 }
 
-static struct xfrm6_tunnel *xfrm6_tunnel_handler;
-static DEFINE_MUTEX(xfrm6_tunnel_mutex);
-
-int xfrm6_tunnel_register(struct xfrm6_tunnel *handler)
+static int xfrm6_tunnel_rcv(struct sk_buff *skb)
 {
-        int ret;
-
-        mutex_lock(&xfrm6_tunnel_mutex);
-        ret = 0;
-        if (xfrm6_tunnel_handler != NULL)
-                ret = -EINVAL;
-        if (!ret)
-                xfrm6_tunnel_handler = handler;
-        mutex_unlock(&xfrm6_tunnel_mutex);
-
-        return ret;
-}
-
-EXPORT_SYMBOL(xfrm6_tunnel_register);
-
-int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler)
-{
-        int ret;
-
-        mutex_lock(&xfrm6_tunnel_mutex);
-        ret = 0;
-        if (xfrm6_tunnel_handler != handler)
-                ret = -EINVAL;
-        if (!ret)
-                xfrm6_tunnel_handler = NULL;
-        mutex_unlock(&xfrm6_tunnel_mutex);
-
-        synchronize_net();
-
-        return ret;
-}
-
-EXPORT_SYMBOL(xfrm6_tunnel_deregister);
-
-static int xfrm6_tunnel_rcv(struct sk_buff **pskb)
-{
-        struct sk_buff *skb = *pskb;
-        struct xfrm6_tunnel *handler = xfrm6_tunnel_handler;
         struct ipv6hdr *iph = skb->nh.ipv6h;
         u32 spi;
 
-        /* device-like_ip6ip6_handler() */
-        if (handler && handler->handler(pskb) == 0)
-                return 0;
-
         spi = xfrm6_tunnel_spi_lookup((xfrm_address_t *)&iph->saddr);
-        return xfrm6_rcv_spi(pskb, spi);
+        return xfrm6_rcv_spi(skb, spi);
 }
 
-static void xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
-                             int type, int code, int offset, __u32 info)
+static int xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
+                            int type, int code, int offset, __u32 info)
 {
-        struct xfrm6_tunnel *handler = xfrm6_tunnel_handler;
-
-        /* call here first for device-like ip6ip6 err handling */
-        if (handler) {
-                handler->err_handler(skb, opt, type, code, offset, info);
-                return;
-        }
-
         /* xfrm6_tunnel native err handling */
         switch (type) {
         case ICMPV6_DEST_UNREACH: 
@@ -462,7 +408,8 @@ static void xfrm6_tunnel_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
         default:
                 break;
         }
-        return;
+
+        return 0;
 }
 
 static int xfrm6_tunnel_init_state(struct xfrm_state *x)
@@ -493,10 +440,10 @@ static struct xfrm_type xfrm6_tunnel_type = {
         .output         = xfrm6_tunnel_output,
 };
 
-static struct inet6_protocol xfrm6_tunnel_protocol = {
+static struct xfrm6_tunnel xfrm6_tunnel_handler = {
         .handler        = xfrm6_tunnel_rcv,
-        .err_handler    = xfrm6_tunnel_err, 
-        .flags          = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
+        .err_handler    = xfrm6_tunnel_err,
+        .priority       = 2,
 };
 
 static int __init xfrm6_tunnel_init(void)
@@ -508,16 +455,16 @@ static int __init xfrm6_tunnel_init(void)
                            "xfrm6_tunnel init: can't add xfrm type\n");
                 return -EAGAIN;
         }
-        if (inet6_add_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6) < 0) {
+        if (xfrm6_tunnel_register(&xfrm6_tunnel_handler)) {
                 X6TPRINTK1(KERN_ERR
-                           "xfrm6_tunnel init(): can't add protocol\n");
+                           "xfrm6_tunnel init(): can't add handler\n");
                 xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
                 return -EAGAIN;
         }
         if (xfrm6_tunnel_spi_init() < 0) {
                 X6TPRINTK1(KERN_ERR
                            "xfrm6_tunnel init: failed to initialize spi\n");
-                inet6_del_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6);
+                xfrm6_tunnel_deregister(&xfrm6_tunnel_handler);
                 xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6);
                 return -EAGAIN;
         }
@@ -529,9 +476,9 @@ static void __exit xfrm6_tunnel_fini(void)
         X6TPRINTK3(KERN_DEBUG "%s()\n", __FUNCTION__);
 
         xfrm6_tunnel_spi_fini();
-        if (inet6_del_protocol(&xfrm6_tunnel_protocol, IPPROTO_IPV6) < 0)
+        if (xfrm6_tunnel_deregister(&xfrm6_tunnel_handler))
                 X6TPRINTK1(KERN_ERR 
-                           "xfrm6_tunnel close: can't remove protocol\n");
+                           "xfrm6_tunnel close: can't remove handler\n");
         if (xfrm_unregister_type(&xfrm6_tunnel_type, AF_INET6) < 0)
                 X6TPRINTK1(KERN_ERR
                            "xfrm6_tunnel close: can't remove xfrm type\n");