diff options
Diffstat (limited to 'kernel/net/ipv6/tunnel6.c')
| -rw-r--r-- | kernel/net/ipv6/tunnel6.c | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/kernel/net/ipv6/tunnel6.c b/kernel/net/ipv6/tunnel6.c new file mode 100644 index 000000000..3c758007b --- /dev/null +++ b/kernel/net/ipv6/tunnel6.c @@ -0,0 +1,183 @@ +/* + * Copyright (C)2003,2004 USAGI/WIDE Project + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, see <http://www.gnu.org/licenses/>. + * + * 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 DEFINE_MUTEX(tunnel6_mutex); + +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); + + for (pprev = (family == AF_INET6) ? &tunnel6_handlers : &tunnel46_handlers; + (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); + + for (pprev = (family == AF_INET6) ? &tunnel6_handlers : &tunnel46_handlers; + (t = rcu_dereference_protected(*pprev, + lockdep_is_held(&tunnel6_mutex))) != NULL; + pprev = &t->next) { + if (t == handler) { + *pprev = handler->next; + ret = 0; + break; + } + } + + 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 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; +} + +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 void 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)) + break; +} + +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 = tunnel6_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; + } + return 0; +} + +static void __exit tunnel6_fini(void) +{ + 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__); +} + +module_init(tunnel6_init); +module_exit(tunnel6_fini); +MODULE_LICENSE("GPL"); |