| /* 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/icmp.h> |
| #include <net/ip.h> |
| #include <net/protocol.h> |
| #include <net/xfrm.h> |
| |
| static struct xfrm_tunnel *tunnel4_handlers; |
| static struct xfrm_tunnel *tunnel64_handlers; |
| static DEFINE_MUTEX(tunnel4_mutex); |
| |
| static inline struct xfrm_tunnel **fam_handlers(unsigned short family) |
| { |
| return (family == AF_INET) ? &tunnel4_handlers : &tunnel64_handlers; |
| } |
| |
| int xfrm4_tunnel_register(struct xfrm_tunnel *handler, unsigned short family) |
| { |
| struct xfrm_tunnel **pprev; |
| int ret = -EEXIST; |
| int priority = handler->priority; |
| |
| mutex_lock(&tunnel4_mutex); |
| |
| for (pprev = fam_handlers(family); *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, unsigned short family) |
| { |
| struct xfrm_tunnel **pprev; |
| int ret = -ENOENT; |
| |
| mutex_lock(&tunnel4_mutex); |
| |
| for (pprev = fam_handlers(family); *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; |
| |
| if (!pskb_may_pull(skb, sizeof(struct iphdr))) |
| goto drop; |
| |
| for (handler = tunnel4_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; |
| } |
| |
| #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; |
| |
| for (handler = tunnel4_handlers; handler; handler = handler->next) |
| if (!handler->err_handler(skb, info)) |
| break; |
| } |
| |
| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| static void tunnel64_err(struct sk_buff *skb, u32 info) |
| { |
| struct xfrm_tunnel *handler; |
| |
| for (handler = tunnel64_handlers; handler; handler = handler->next) |
| if (!handler->err_handler(skb, info)) |
| break; |
| } |
| #endif |
| |
| static struct net_protocol tunnel4_protocol = { |
| .handler = tunnel4_rcv, |
| .err_handler = tunnel4_err, |
| .no_policy = 1, |
| .netns_ok = 1, |
| }; |
| |
| #if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE) |
| static struct net_protocol tunnel64_protocol = { |
| .handler = tunnel64_rcv, |
| .err_handler = tunnel64_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"); |
| } |
| |
| module_init(tunnel4_init); |
| module_exit(tunnel4_fini); |
| MODULE_LICENSE("GPL"); |