Adding upstream version 4.19.249.upstream/4.19.249upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 250 insertions, 0 deletions

diff --git a/net/ipv4/tunnel4.c b/net/ipv4/tunnel4.c
new file mode 100644
index 000000000..c0630013c
--- /dev/null
+++ b/net/ipv4/tunnel4.c
@@ -0,0 +1,250 @@
+/* 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_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 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
+
+#if IS_ENABLED(CONFIG_MPLS)
+static void 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))
+			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
+
+#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
+	return 0;
+
+err:
+	pr_err("%s: can't add protocol\n", __func__);
+	return -EAGAIN;
+}
+
+static void __exit tunnel4_fini(void)
+{
+#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");