Add the rt linux 4.1.3-rt3 as base

[kvmfornfv.git] / kernel / net / ipv4 / tunnel4.c

diff --git a/kernel/net/ipv4/tunnel4.c b/kernel/net/ipv4/tunnel4.c
new file mode 100644 (file)
index 0000000..0d01718
--- /dev/null
+++ b/kernel/net/ipv4/tunnel4.c
@@ -0,0 +1,192 @@
+/* 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 <linux/slab.h>
+#include <net/icmp.h>
+#include <net/ip.h>
+#include <net/protocol.h>
+#include <net/xfrm.h>
+
+static struct xfrm_tunnel __rcu *tunnel4_handlers __read_mostly;
+static struct xfrm_tunnel __rcu *tunnel64_handlers __read_mostly;
+static DEFINE_MUTEX(tunnel4_mutex);
+
+static inline struct xfrm_tunnel __rcu **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 __rcu **pprev;
+       struct xfrm_tunnel *t;
+
+       int ret = -EEXIST;
+       int priority = handler->priority;
+
+       mutex_lock(&tunnel4_mutex);
+
+       for (pprev = fam_handlers(family);
+            (t = rcu_dereference_protected(*pprev,
+                       lockdep_is_held(&tunnel4_mutex))) != NULL;
+            pprev = &t->next) {
+               if (t->priority > priority)
+                       break;
+               if (t->priority == priority)
+                       goto err;
+       }
+
+       handler->next = *pprev;
+       rcu_assign_pointer(*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 __rcu **pprev;
+       struct xfrm_tunnel *t;
+       int ret = -ENOENT;
+
+       mutex_lock(&tunnel4_mutex);
+
+       for (pprev = fam_handlers(family);
+            (t = rcu_dereference_protected(*pprev,
+                       lockdep_is_held(&tunnel4_mutex))) != NULL;
+            pprev = &t->next) {
+               if (t == handler) {
+                       *pprev = handler->next;
+                       ret = 0;
+                       break;
+               }
+       }
+
+       mutex_unlock(&tunnel4_mutex);
+
+       synchronize_net();
+
+       return ret;
+}
+EXPORT_SYMBOL(xfrm4_tunnel_deregister);
+
+#define for_each_tunnel_rcu(head, handler)             \
+       for (handler = rcu_dereference(head);           \
+            handler != NULL;                           \
+            handler = rcu_dereference(handler->next))  \
+       
+static int tunnel4_rcv(struct sk_buff *skb)
+{
+       struct xfrm_tunnel *handler;
+
+       if (!pskb_may_pull(skb, sizeof(struct iphdr)))
+               goto drop;
+
+       for_each_tunnel_rcu(tunnel4_handlers, handler)
+               if (!handler->handler(skb))
+                       return 0;
+
+       icmp_send(skb, ICMP_DEST_UNREACH, ICMP_PORT_UNREACH, 0);
+
+drop:
+       kfree_skb(skb);
+       return 0;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static int tunnel64_rcv(struct sk_buff *skb)
+{
+       struct xfrm_tunnel *handler;
+
+       if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
+               goto drop;
+
+       for_each_tunnel_rcu(tunnel64_handlers, handler)
+               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_each_tunnel_rcu(tunnel4_handlers, handler)
+               if (!handler->err_handler(skb, info))
+                       break;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static void tunnel64_err(struct sk_buff *skb, u32 info)
+{
+       struct xfrm_tunnel *handler;
+
+       for_each_tunnel_rcu(tunnel64_handlers, handler)
+               if (!handler->err_handler(skb, info))
+                       break;
+}
+#endif
+
+static const struct net_protocol tunnel4_protocol = {
+       .handler        =       tunnel4_rcv,
+       .err_handler    =       tunnel4_err,
+       .no_policy      =       1,
+       .netns_ok       =       1,
+};
+
+#if IS_ENABLED(CONFIG_IPV6)
+static const struct net_protocol tunnel64_protocol = {
+       .handler        =       tunnel64_rcv,
+       .err_handler    =       tunnel64_err,
+       .no_policy      =       1,
+       .netns_ok       =       1,
+};
+#endif
+
+static int __init tunnel4_init(void)
+{
+       if (inet_add_protocol(&tunnel4_protocol, IPPROTO_IPIP)) {
+               pr_err("%s: can't add protocol\n", __func__);
+               return -EAGAIN;
+       }
+#if IS_ENABLED(CONFIG_IPV6)
+       if (inet_add_protocol(&tunnel64_protocol, IPPROTO_IPV6)) {
+               pr_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 IS_ENABLED(CONFIG_IPV6)
+       if (inet_del_protocol(&tunnel64_protocol, IPPROTO_IPV6))
+               pr_err("tunnel64 close: can't remove protocol\n");
+#endif
+       if (inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP))
+               pr_err("tunnel4 close: can't remove protocol\n");
+}
+
+module_init(tunnel4_init);
+module_exit(tunnel4_fini);
+MODULE_LICENSE("GPL");