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-rw-r--r--net/ipv4/tunnel4.c300
1 files changed, 300 insertions, 0 deletions
diff --git a/net/ipv4/tunnel4.c b/net/ipv4/tunnel4.c
new file mode 100644
index 000000000..e44aaf41a
--- /dev/null
+++ b/net/ipv4/tunnel4.c
@@ -0,0 +1,300 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/* 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/mpls.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 struct xfrm_tunnel __rcu *tunnelmpls4_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 :
+ (family == AF_INET6) ? &tunnel64_handlers :
+ &tunnelmpls4_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_INET_XFRM_TUNNEL)
+static int tunnel4_rcv_cb(struct sk_buff *skb, u8 proto, int err)
+{
+ struct xfrm_tunnel __rcu *head;
+ struct xfrm_tunnel *handler;
+ int ret;
+
+ head = (proto == IPPROTO_IPIP) ? tunnel4_handlers : tunnel64_handlers;
+
+ for_each_tunnel_rcu(head, handler) {
+ if (handler->cb_handler) {
+ ret = handler->cb_handler(skb, err);
+ if (ret <= 0)
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static const struct xfrm_input_afinfo tunnel4_input_afinfo = {
+ .family = AF_INET,
+ .is_ipip = true,
+ .callback = tunnel4_rcv_cb,
+};
+#endif
+
+#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
+
+#if IS_ENABLED(CONFIG_MPLS)
+static int tunnelmpls4_rcv(struct sk_buff *skb)
+{
+ struct xfrm_tunnel *handler;
+
+ if (!pskb_may_pull(skb, sizeof(struct mpls_label)))
+ goto drop;
+
+ for_each_tunnel_rcu(tunnelmpls4_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 int 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))
+ return 0;
+
+ return -ENOENT;
+}
+
+#if IS_ENABLED(CONFIG_IPV6)
+static int 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))
+ return 0;
+
+ return -ENOENT;
+}
+#endif
+
+#if IS_ENABLED(CONFIG_MPLS)
+static int tunnelmpls4_err(struct sk_buff *skb, u32 info)
+{
+ struct xfrm_tunnel *handler;
+
+ for_each_tunnel_rcu(tunnelmpls4_handlers, handler)
+ if (!handler->err_handler(skb, info))
+ return 0;
+
+ return -ENOENT;
+}
+#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
+
+#if IS_ENABLED(CONFIG_MPLS)
+static const struct net_protocol tunnelmpls4_protocol = {
+ .handler = tunnelmpls4_rcv,
+ .err_handler = tunnelmpls4_err,
+ .no_policy = 1,
+ .netns_ok = 1,
+};
+#endif
+
+static int __init tunnel4_init(void)
+{
+ if (inet_add_protocol(&tunnel4_protocol, IPPROTO_IPIP))
+ goto err;
+#if IS_ENABLED(CONFIG_IPV6)
+ if (inet_add_protocol(&tunnel64_protocol, IPPROTO_IPV6)) {
+ inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP);
+ goto err;
+ }
+#endif
+#if IS_ENABLED(CONFIG_MPLS)
+ if (inet_add_protocol(&tunnelmpls4_protocol, IPPROTO_MPLS)) {
+ inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP);
+#if IS_ENABLED(CONFIG_IPV6)
+ inet_del_protocol(&tunnel64_protocol, IPPROTO_IPV6);
+#endif
+ goto err;
+ }
+#endif
+#if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL)
+ if (xfrm_input_register_afinfo(&tunnel4_input_afinfo)) {
+ inet_del_protocol(&tunnel4_protocol, IPPROTO_IPIP);
+#if IS_ENABLED(CONFIG_IPV6)
+ inet_del_protocol(&tunnel64_protocol, IPPROTO_IPV6);
+#endif
+#if IS_ENABLED(CONFIG_MPLS)
+ inet_del_protocol(&tunnelmpls4_protocol, IPPROTO_MPLS);
+#endif
+ goto err;
+ }
+#endif
+ return 0;
+
+err:
+ pr_err("%s: can't add protocol\n", __func__);
+ return -EAGAIN;
+}
+
+static void __exit tunnel4_fini(void)
+{
+#if IS_ENABLED(CONFIG_INET_XFRM_TUNNEL)
+ if (xfrm_input_unregister_afinfo(&tunnel4_input_afinfo))
+ pr_err("tunnel4 close: can't remove input afinfo\n");
+#endif
+#if IS_ENABLED(CONFIG_MPLS)
+ if (inet_del_protocol(&tunnelmpls4_protocol, IPPROTO_MPLS))
+ pr_err("tunnelmpls4 close: can't remove protocol\n");
+#endif
+#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");
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-01 13:43:09 +0000