linux-sg2042/net/ipv4/xfrm4_tunnel.c

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/* xfrm4_tunnel.c: Generic IP tunnel transformer.
*
* Copyright (C) 2003 David S. Miller (davem@redhat.com)
*/
#define pr_fmt(fmt) "IPsec: " fmt
#include <linux/skbuff.h>
#include <linux/module.h>
#include <linux/mutex.h>
#include <net/xfrm.h>
#include <net/ip.h>
#include <net/protocol.h>
static int ipip_output(struct xfrm_state *x, struct sk_buff *skb)
{
skb_push(skb, -skb_network_offset(skb));
return 0;
}
static int ipip_xfrm_rcv(struct xfrm_state *x, struct sk_buff *skb)
{
return ip_hdr(skb)->protocol;
}
static int ipip_init_state(struct xfrm_state *x)
{
if (x->props.mode != XFRM_MODE_TUNNEL)
return -EINVAL;
if (x->encap)
return -EINVAL;
x->props.header_len = sizeof(struct iphdr);
return 0;
}
static void ipip_destroy(struct xfrm_state *x)
{
}
static const struct xfrm_type ipip_type = {
.description = "IPIP",
.owner = THIS_MODULE,
.proto = IPPROTO_IPIP,
.init_state = ipip_init_state,
.destructor = ipip_destroy,
.input = ipip_xfrm_rcv,
.output = ipip_output
};
static int xfrm_tunnel_rcv(struct sk_buff *skb)
{
return xfrm4_rcv_spi(skb, IPPROTO_IPIP, ip_hdr(skb)->saddr);
}
[INET]: Introduce tunnel4/tunnel6 Basically this patch moves the generic tunnel protocol stuff out of xfrm4_tunnel/xfrm6_tunnel and moves it into the new files of tunnel4.c and tunnel6 respectively. The reason for this is that the problem that Hugo uncovered is only the tip of the iceberg. The real problem is that when we removed the dependency of ipip on xfrm4_tunnel we didn't really consider the module case at all. For instance, as it is it's possible to build both ipip and xfrm4_tunnel as modules and if the latter is loaded then ipip simply won't load. After considering the alternatives I've decided that the best way out of this is to restore the dependency of ipip on the non-xfrm-specific part of xfrm4_tunnel. This is acceptable IMHO because the intention of the removal was really to be able to use ipip without the xfrm subsystem. This is still preserved by this patch. So now both ipip/xfrm4_tunnel depend on the new tunnel4.c which handles the arbitration between the two. The order of processing is determined by a simple integer which ensures that ipip gets processed before xfrm4_tunnel. The situation for ICMP handling is a little bit more complicated since we may not have enough information to determine who it's for. It's not a big deal at the moment since the xfrm ICMP handlers are basically no-ops. In future we can deal with this when we look at ICMP caching in general. The user-visible change to this is the removal of the TUNNEL Kconfig prompts. This makes sense because it can only be used through IPCOMP as it stands. The addition of the new modules shouldn't introduce any problems since module dependency will cause them to be loaded. Oh and I also turned some unnecessary pskb's in IPv6 related to this patch to skb's. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-28 17:12:13 +08:00
static int xfrm_tunnel_err(struct sk_buff *skb, u32 info)
{
return -ENOENT;
}
static struct xfrm_tunnel xfrm_tunnel_handler __read_mostly = {
.handler = xfrm_tunnel_rcv,
[INET]: Introduce tunnel4/tunnel6 Basically this patch moves the generic tunnel protocol stuff out of xfrm4_tunnel/xfrm6_tunnel and moves it into the new files of tunnel4.c and tunnel6 respectively. The reason for this is that the problem that Hugo uncovered is only the tip of the iceberg. The real problem is that when we removed the dependency of ipip on xfrm4_tunnel we didn't really consider the module case at all. For instance, as it is it's possible to build both ipip and xfrm4_tunnel as modules and if the latter is loaded then ipip simply won't load. After considering the alternatives I've decided that the best way out of this is to restore the dependency of ipip on the non-xfrm-specific part of xfrm4_tunnel. This is acceptable IMHO because the intention of the removal was really to be able to use ipip without the xfrm subsystem. This is still preserved by this patch. So now both ipip/xfrm4_tunnel depend on the new tunnel4.c which handles the arbitration between the two. The order of processing is determined by a simple integer which ensures that ipip gets processed before xfrm4_tunnel. The situation for ICMP handling is a little bit more complicated since we may not have enough information to determine who it's for. It's not a big deal at the moment since the xfrm ICMP handlers are basically no-ops. In future we can deal with this when we look at ICMP caching in general. The user-visible change to this is the removal of the TUNNEL Kconfig prompts. This makes sense because it can only be used through IPCOMP as it stands. The addition of the new modules shouldn't introduce any problems since module dependency will cause them to be loaded. Oh and I also turned some unnecessary pskb's in IPv6 related to this patch to skb's. Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au> Signed-off-by: David S. Miller <davem@davemloft.net>
2006-03-28 17:12:13 +08:00
.err_handler = xfrm_tunnel_err,
.priority = 2,
};
#if IS_ENABLED(CONFIG_IPV6)
static struct xfrm_tunnel xfrm64_tunnel_handler __read_mostly = {
.handler = xfrm_tunnel_rcv,
.err_handler = xfrm_tunnel_err,
.priority = 2,
};
#endif
static int __init ipip_init(void)
{
if (xfrm_register_type(&ipip_type, AF_INET) < 0) {
pr_info("%s: can't add xfrm type\n", __func__);
return -EAGAIN;
}
if (xfrm4_tunnel_register(&xfrm_tunnel_handler, AF_INET)) {
pr_info("%s: can't add xfrm handler for AF_INET\n", __func__);
xfrm_unregister_type(&ipip_type, AF_INET);
return -EAGAIN;
}
#if IS_ENABLED(CONFIG_IPV6)
if (xfrm4_tunnel_register(&xfrm64_tunnel_handler, AF_INET6)) {
pr_info("%s: can't add xfrm handler for AF_INET6\n", __func__);
xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET);
xfrm_unregister_type(&ipip_type, AF_INET);
return -EAGAIN;
}
#endif
return 0;
}
static void __exit ipip_fini(void)
{
#if IS_ENABLED(CONFIG_IPV6)
if (xfrm4_tunnel_deregister(&xfrm64_tunnel_handler, AF_INET6))
pr_info("%s: can't remove xfrm handler for AF_INET6\n",
__func__);
#endif
if (xfrm4_tunnel_deregister(&xfrm_tunnel_handler, AF_INET))
pr_info("%s: can't remove xfrm handler for AF_INET\n",
__func__);
if (xfrm_unregister_type(&ipip_type, AF_INET) < 0)
pr_info("%s: can't remove xfrm type\n", __func__);
}
module_init(ipip_init);
module_exit(ipip_fini);
MODULE_LICENSE("GPL");
MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_IPIP);