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// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C)2003,2004 USAGI/WIDE Project
*
* Authors Mitsuru KANDA <mk@linux-ipv6.org>
* YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
*/
#define pr_fmt(fmt) "IPv6: " fmt
#include <linux/icmpv6.h>
#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/ipv6.h>
#include <net/protocol.h>
#include <net/xfrm.h>
static struct xfrm6_tunnel __rcu *tunnel6_handlers __read_mostly;
static struct xfrm6_tunnel __rcu *tunnel46_handlers __read_mostly;
static struct xfrm6_tunnel __rcu *tunnelmpls6_handlers __read_mostly;
static DEFINE_MUTEX(tunnel6_mutex);
static inline int xfrm6_tunnel_mpls_supported(void)
{
return IS_ENABLED(CONFIG_MPLS);
}
int xfrm6_tunnel_register(struct xfrm6_tunnel *handler, unsigned short family)
{
struct xfrm6_tunnel __rcu **pprev;
struct xfrm6_tunnel *t;
int ret = -EEXIST;
int priority = handler->priority;
mutex_lock(&tunnel6_mutex);
switch (family) {
case AF_INET6:
pprev = &tunnel6_handlers;
break;
case AF_INET:
pprev = &tunnel46_handlers;
break;
case AF_MPLS:
pprev = &tunnelmpls6_handlers;
break;
default:
goto err;
}
for (; (t = rcu_dereference_protected(*pprev,
lockdep_is_held(&tunnel6_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(&tunnel6_mutex);
return ret;
}
EXPORT_SYMBOL(xfrm6_tunnel_register);
int xfrm6_tunnel_deregister(struct xfrm6_tunnel *handler, unsigned short family)
{
struct xfrm6_tunnel __rcu **pprev;
struct xfrm6_tunnel *t;
int ret = -ENOENT;
mutex_lock(&tunnel6_mutex);
switch (family) {
case AF_INET6:
pprev = &tunnel6_handlers;
break;
case AF_INET:
pprev = &tunnel46_handlers;
break;
case AF_MPLS:
pprev = &tunnelmpls6_handlers;
break;
default:
goto err;
}
for (; (t = rcu_dereference_protected(*pprev,
lockdep_is_held(&tunnel6_mutex))) != NULL;
pprev = &t->next) {
if (t == handler) {
*pprev = handler->next;
ret = 0;
break;
}
}
err:
mutex_unlock(&tunnel6_mutex);
synchronize_net();
return ret;
}
EXPORT_SYMBOL(xfrm6_tunnel_deregister);
#define for_each_tunnel_rcu(head, handler) \
for (handler = rcu_dereference(head); \
handler != NULL; \
handler = rcu_dereference(handler->next)) \
static int tunnelmpls6_rcv(struct sk_buff *skb)
{
struct xfrm6_tunnel *handler;
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
goto drop;
for_each_tunnel_rcu(tunnelmpls6_handlers, handler)
if (!handler->handler(skb))
return 0;
icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
drop:
kfree_skb(skb);
return 0;
}
static int tunnel6_rcv(struct sk_buff *skb)
{
struct xfrm6_tunnel *handler;
if (!pskb_may_pull(skb, sizeof(struct ipv6hdr)))
goto drop;
for_each_tunnel_rcu(tunnel6_handlers, handler)
if (!handler->handler(skb))
return 0;
icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
drop:
kfree_skb(skb);
return 0;
}
#if IS_ENABLED(CONFIG_INET6_XFRM_TUNNEL)
static int tunnel6_rcv_cb(struct sk_buff *skb, u8 proto, int err)
{
struct xfrm6_tunnel __rcu *head;
struct xfrm6_tunnel *handler;
int ret;
head = (proto == IPPROTO_IPV6) ? tunnel6_handlers : tunnel46_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 tunnel6_input_afinfo = {
.family = AF_INET6,
.is_ipip = true,
.callback = tunnel6_rcv_cb,
};
#endif
static int tunnel46_rcv(struct sk_buff *skb)
{
struct xfrm6_tunnel *handler;
if (!pskb_may_pull(skb, sizeof(struct iphdr)))
goto drop;
for_each_tunnel_rcu(tunnel46_handlers, handler)
if (!handler->handler(skb))
return 0;
icmpv6_send(skb, ICMPV6_DEST_UNREACH, ICMPV6_PORT_UNREACH, 0);
drop:
kfree_skb(skb);
return 0;
}
static int tunnel6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
u8 type, u8 code, int offset, __be32 info)
{
struct xfrm6_tunnel *handler;
for_each_tunnel_rcu(tunnel6_handlers, handler)
if (!handler->err_handler(skb, opt, type, code, offset, info))
return 0;
return -ENOENT;
}
static int tunnel46_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
u8 type, u8 code, int offset, __be32 info)
{
struct xfrm6_tunnel *handler;
for_each_tunnel_rcu(tunnel46_handlers, handler)
if (!handler->err_handler(skb, opt, type, code, offset, info))
return 0;
return -ENOENT;
}
static int tunnelmpls6_err(struct sk_buff *skb, struct inet6_skb_parm *opt,
u8 type, u8 code, int offset, __be32 info)
{
struct xfrm6_tunnel *handler;
for_each_tunnel_rcu(tunnelmpls6_handlers, handler)
if (!handler->err_handler(skb, opt, type, code, offset, info))
return 0;
return -ENOENT;
}
static const struct inet6_protocol tunnel6_protocol = {
.handler = tunnel6_rcv,
.err_handler = tunnel6_err,
.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};
static const struct inet6_protocol tunnel46_protocol = {
.handler = tunnel46_rcv,
.err_handler = tunnel46_err,
.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};
static const struct inet6_protocol tunnelmpls6_protocol = {
.handler = tunnelmpls6_rcv,
.err_handler = tunnelmpls6_err,
.flags = INET6_PROTO_NOPOLICY|INET6_PROTO_FINAL,
};
static int __init tunnel6_init(void)
{
if (inet6_add_protocol(&tunnel6_protocol, IPPROTO_IPV6)) {
pr_err("%s: can't add protocol\n", __func__);
return -EAGAIN;
}
if (inet6_add_protocol(&tunnel46_protocol, IPPROTO_IPIP)) {
pr_err("%s: can't add protocol\n", __func__);
inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6);
return -EAGAIN;
}
if (xfrm6_tunnel_mpls_supported() &&
inet6_add_protocol(&tunnelmpls6_protocol, IPPROTO_MPLS)) {
pr_err("%s: can't add protocol\n", __func__);
inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6);
inet6_del_protocol(&tunnel46_protocol, IPPROTO_IPIP);
return -EAGAIN;
}
#if IS_ENABLED(CONFIG_INET6_XFRM_TUNNEL)
if (xfrm_input_register_afinfo(&tunnel6_input_afinfo)) {
pr_err("%s: can't add input afinfo\n", __func__);
inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6);
inet6_del_protocol(&tunnel46_protocol, IPPROTO_IPIP);
if (xfrm6_tunnel_mpls_supported())
inet6_del_protocol(&tunnelmpls6_protocol, IPPROTO_MPLS);
return -EAGAIN;
}
#endif
return 0;
}
static void __exit tunnel6_fini(void)
{
#if IS_ENABLED(CONFIG_INET6_XFRM_TUNNEL)
if (xfrm_input_unregister_afinfo(&tunnel6_input_afinfo))
pr_err("%s: can't remove input afinfo\n", __func__);
#endif
if (inet6_del_protocol(&tunnel46_protocol, IPPROTO_IPIP))
pr_err("%s: can't remove protocol\n", __func__);
if (inet6_del_protocol(&tunnel6_protocol, IPPROTO_IPV6))
pr_err("%s: can't remove protocol\n", __func__);
if (xfrm6_tunnel_mpls_supported() &&
inet6_del_protocol(&tunnelmpls6_protocol, IPPROTO_MPLS))
pr_err("%s: can't remove protocol\n", __func__);
}
module_init(tunnel6_init);
module_exit(tunnel6_fini);
MODULE_LICENSE("GPL");
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