diff options
Diffstat (limited to 'net')
| -rw-r--r-- | net/ipv4/Kconfig | 7 | ||||
| -rw-r--r-- | net/ipv4/Makefile | 1 | ||||
| -rw-r--r-- | net/ipv4/gre.c | 151 | ||||
| -rw-r--r-- | net/ipv4/ip_gre.c | 14 |
4 files changed, 166 insertions, 7 deletions
diff --git a/net/ipv4/Kconfig b/net/ipv4/Kconfig index 7c3a7d191249..7458bdae7e9f 100644 --- a/net/ipv4/Kconfig +++ b/net/ipv4/Kconfig @@ -215,8 +215,15 @@ config NET_IPIP be inserted in and removed from the running kernel whenever you want). Most people won't need this and can say N. +config NET_IPGRE_DEMUX + tristate "IP: GRE demultiplexer" + help + This is helper module to demultiplex GRE packets on GRE version field criteria. + Required by ip_gre and pptp modules. + config NET_IPGRE tristate "IP: GRE tunnels over IP" + depends on NET_IPGRE_DEMUX help Tunneling means encapsulating data of one protocol type within another protocol and sending it over a channel that understands the diff --git a/net/ipv4/Makefile b/net/ipv4/Makefile index 80ff87ce43aa..4978d22f9a75 100644 --- a/net/ipv4/Makefile +++ b/net/ipv4/Makefile @@ -20,6 +20,7 @@ obj-$(CONFIG_PROC_FS) += proc.o obj-$(CONFIG_IP_MULTIPLE_TABLES) += fib_rules.o obj-$(CONFIG_IP_MROUTE) += ipmr.o obj-$(CONFIG_NET_IPIP) += ipip.o +obj-$(CONFIG_NET_IPGRE_DEMUX) += gre.o obj-$(CONFIG_NET_IPGRE) += ip_gre.o obj-$(CONFIG_SYN_COOKIES) += syncookies.o obj-$(CONFIG_INET_AH) += ah4.o diff --git a/net/ipv4/gre.c b/net/ipv4/gre.c new file mode 100644 index 000000000000..b546736da2e1 --- /dev/null +++ b/net/ipv4/gre.c @@ -0,0 +1,151 @@ +/* + * GRE over IPv4 demultiplexer driver + * + * Authors: Dmitry Kozlov (xeb@mail.ru) + * + * 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. + * + */ + +#include <linux/module.h> +#include <linux/kernel.h> +#include <linux/kmod.h> +#include <linux/skbuff.h> +#include <linux/in.h> +#include <linux/netdevice.h> +#include <linux/version.h> +#include <linux/spinlock.h> +#include <net/protocol.h> +#include <net/gre.h> + + +const struct gre_protocol *gre_proto[GREPROTO_MAX] __read_mostly; +static DEFINE_SPINLOCK(gre_proto_lock); + +int gre_add_protocol(const struct gre_protocol *proto, u8 version) +{ + if (version >= GREPROTO_MAX) + goto err_out; + + spin_lock(&gre_proto_lock); + if (gre_proto[version]) + goto err_out_unlock; + + rcu_assign_pointer(gre_proto[version], proto); + spin_unlock(&gre_proto_lock); + return 0; + +err_out_unlock: + spin_unlock(&gre_proto_lock); +err_out: + return -1; +} +EXPORT_SYMBOL_GPL(gre_add_protocol); + +int gre_del_protocol(const struct gre_protocol *proto, u8 version) +{ + if (version >= GREPROTO_MAX) + goto err_out; + + spin_lock(&gre_proto_lock); + if (gre_proto[version] != proto) + goto err_out_unlock; + rcu_assign_pointer(gre_proto[version], NULL); + spin_unlock(&gre_proto_lock); + synchronize_rcu(); + return 0; + +err_out_unlock: + spin_unlock(&gre_proto_lock); +err_out: + return -1; +} +EXPORT_SYMBOL_GPL(gre_del_protocol); + +static int gre_rcv(struct sk_buff *skb) +{ + const struct gre_protocol *proto; + u8 ver; + int ret; + + if (!pskb_may_pull(skb, 12)) + goto drop; + + ver = skb->data[1]&0x7f; + if (ver >= GREPROTO_MAX) + goto drop; + + rcu_read_lock(); + proto = rcu_dereference(gre_proto[ver]); + if (!proto || !proto->handler) + goto drop_unlock; + ret = proto->handler(skb); + rcu_read_unlock(); + return ret; + +drop_unlock: + rcu_read_unlock(); +drop: + kfree_skb(skb); + return NET_RX_DROP; +} + +static void gre_err(struct sk_buff *skb, u32 info) +{ + const struct gre_protocol *proto; + u8 ver; + + if (!pskb_may_pull(skb, 12)) + goto drop; + + ver = skb->data[1]&0x7f; + if (ver >= GREPROTO_MAX) + goto drop; + + rcu_read_lock(); + proto = rcu_dereference(gre_proto[ver]); + if (!proto || !proto->err_handler) + goto drop_unlock; + proto->err_handler(skb, info); + rcu_read_unlock(); + return; + +drop_unlock: + rcu_read_unlock(); +drop: + kfree_skb(skb); +} + +static const struct net_protocol net_gre_protocol = { + .handler = gre_rcv, + .err_handler = gre_err, + .netns_ok = 1, +}; + +static int __init gre_init(void) +{ + pr_info("GRE over IPv4 demultiplexor driver"); + + if (inet_add_protocol(&net_gre_protocol, IPPROTO_GRE) < 0) { + pr_err("gre: can't add protocol\n"); + return -EAGAIN; + } + + return 0; +} + +static void __exit gre_exit(void) +{ + inet_del_protocol(&net_gre_protocol, IPPROTO_GRE); +} + +module_init(gre_init); +module_exit(gre_exit); + +MODULE_DESCRIPTION("GRE over IPv4 demultiplexer driver"); +MODULE_AUTHOR("D. Kozlov (xeb@mail.ru)"); +MODULE_LICENSE("GPL"); + diff --git a/net/ipv4/ip_gre.c b/net/ipv4/ip_gre.c index 945b20a5ad50..85176895495a 100644 --- a/net/ipv4/ip_gre.c +++ b/net/ipv4/ip_gre.c @@ -44,6 +44,7 @@ #include <net/net_namespace.h> #include <net/netns/generic.h> #include <net/rtnetlink.h> +#include <net/gre.h> #ifdef CONFIG_IPV6 #include <net/ipv6.h> @@ -1278,10 +1279,9 @@ static void ipgre_fb_tunnel_init(struct net_device *dev) } -static const struct net_protocol ipgre_protocol = { - .handler = ipgre_rcv, - .err_handler = ipgre_err, - .netns_ok = 1, +static const struct gre_protocol ipgre_protocol = { + .handler = ipgre_rcv, + .err_handler = ipgre_err, }; static void ipgre_destroy_tunnels(struct ipgre_net *ign, struct list_head *head) @@ -1663,7 +1663,7 @@ static int __init ipgre_init(void) if (err < 0) return err; - err = inet_add_protocol(&ipgre_protocol, IPPROTO_GRE); + err = gre_add_protocol(&ipgre_protocol, GREPROTO_CISCO); if (err < 0) { printk(KERN_INFO "ipgre init: can't add protocol\n"); goto add_proto_failed; @@ -1683,7 +1683,7 @@ out: tap_ops_failed: rtnl_link_unregister(&ipgre_link_ops); rtnl_link_failed: - inet_del_protocol(&ipgre_protocol, IPPROTO_GRE); + gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO); add_proto_failed: unregister_pernet_device(&ipgre_net_ops); goto out; @@ -1693,7 +1693,7 @@ static void __exit ipgre_fini(void) { rtnl_link_unregister(&ipgre_tap_ops); rtnl_link_unregister(&ipgre_link_ops); - if (inet_del_protocol(&ipgre_protocol, IPPROTO_GRE) < 0) + if (gre_del_protocol(&ipgre_protocol, GREPROTO_CISCO) < 0) printk(KERN_INFO "ipgre close: can't remove protocol\n"); unregister_pernet_device(&ipgre_net_ops); } |