kernel-aes67/net/ipv6/xfrm6_policy.c
Masahide NAKAMURA 7e49e6de30 [XFRM]: Add XFRM_MODE_xxx for future use.
Transformation mode is used as either IPsec transport or tunnel.
It is required to add two more items, route optimization and inbound trigger
for Mobile IPv6.
Based on MIPL2 kernel patch.

This patch was also written by: Ville Nuorvala <vnuorval@tcs.hut.fi>

Signed-off-by: Masahide NAKAMURA <nakam@linux-ipv6.org>
Signed-off-by: YOSHIFUJI Hideaki <yoshfuji@linux-ipv6.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
2006-09-22 15:05:15 -07:00

338 lines
8.1 KiB
C

/*
* xfrm6_policy.c: based on xfrm4_policy.c
*
* Authors:
* Mitsuru KANDA @USAGI
* Kazunori MIYAZAWA @USAGI
* Kunihiro Ishiguro <kunihiro@ipinfusion.com>
* IPv6 support
* YOSHIFUJI Hideaki
* Split up af-specific portion
*
*/
#include <linux/compiler.h>
#include <linux/netdevice.h>
#include <net/addrconf.h>
#include <net/xfrm.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/ip6_route.h>
static struct dst_ops xfrm6_dst_ops;
static struct xfrm_policy_afinfo xfrm6_policy_afinfo;
static int xfrm6_dst_lookup(struct xfrm_dst **dst, struct flowi *fl)
{
int err = 0;
*dst = (struct xfrm_dst*)ip6_route_output(NULL, fl);
if (!*dst)
err = -ENETUNREACH;
return err;
}
static struct dst_entry *
__xfrm6_find_bundle(struct flowi *fl, struct xfrm_policy *policy)
{
struct dst_entry *dst;
/* Still not clear if we should set fl->fl6_{src,dst}... */
read_lock_bh(&policy->lock);
for (dst = policy->bundles; dst; dst = dst->next) {
struct xfrm_dst *xdst = (struct xfrm_dst*)dst;
struct in6_addr fl_dst_prefix, fl_src_prefix;
ipv6_addr_prefix(&fl_dst_prefix,
&fl->fl6_dst,
xdst->u.rt6.rt6i_dst.plen);
ipv6_addr_prefix(&fl_src_prefix,
&fl->fl6_src,
xdst->u.rt6.rt6i_src.plen);
if (ipv6_addr_equal(&xdst->u.rt6.rt6i_dst.addr, &fl_dst_prefix) &&
ipv6_addr_equal(&xdst->u.rt6.rt6i_src.addr, &fl_src_prefix) &&
xfrm_bundle_ok(xdst, fl, AF_INET6)) {
dst_clone(dst);
break;
}
}
read_unlock_bh(&policy->lock);
return dst;
}
/* Allocate chain of dst_entry's, attach known xfrm's, calculate
* all the metrics... Shortly, bundle a bundle.
*/
static int
__xfrm6_bundle_create(struct xfrm_policy *policy, struct xfrm_state **xfrm, int nx,
struct flowi *fl, struct dst_entry **dst_p)
{
struct dst_entry *dst, *dst_prev;
struct rt6_info *rt0 = (struct rt6_info*)(*dst_p);
struct rt6_info *rt = rt0;
struct in6_addr *remote = &fl->fl6_dst;
struct in6_addr *local = &fl->fl6_src;
struct flowi fl_tunnel = {
.nl_u = {
.ip6_u = {
.saddr = *local,
.daddr = *remote
}
}
};
int i;
int err = 0;
int header_len = 0;
int trailer_len = 0;
dst = dst_prev = NULL;
dst_hold(&rt->u.dst);
for (i = 0; i < nx; i++) {
struct dst_entry *dst1 = dst_alloc(&xfrm6_dst_ops);
struct xfrm_dst *xdst;
int tunnel = 0;
if (unlikely(dst1 == NULL)) {
err = -ENOBUFS;
dst_release(&rt->u.dst);
goto error;
}
if (!dst)
dst = dst1;
else {
dst_prev->child = dst1;
dst1->flags |= DST_NOHASH;
dst_clone(dst1);
}
xdst = (struct xfrm_dst *)dst1;
xdst->route = &rt->u.dst;
if (rt->rt6i_node)
xdst->route_cookie = rt->rt6i_node->fn_sernum;
dst1->next = dst_prev;
dst_prev = dst1;
if (xfrm[i]->props.mode != XFRM_MODE_TRANSPORT) {
remote = (struct in6_addr*)&xfrm[i]->id.daddr;
local = (struct in6_addr*)&xfrm[i]->props.saddr;
tunnel = 1;
}
header_len += xfrm[i]->props.header_len;
trailer_len += xfrm[i]->props.trailer_len;
if (tunnel) {
ipv6_addr_copy(&fl_tunnel.fl6_dst, remote);
ipv6_addr_copy(&fl_tunnel.fl6_src, local);
err = xfrm_dst_lookup((struct xfrm_dst **) &rt,
&fl_tunnel, AF_INET6);
if (err)
goto error;
} else
dst_hold(&rt->u.dst);
}
dst_prev->child = &rt->u.dst;
dst->path = &rt->u.dst;
if (rt->rt6i_node)
((struct xfrm_dst *)dst)->path_cookie = rt->rt6i_node->fn_sernum;
*dst_p = dst;
dst = dst_prev;
dst_prev = *dst_p;
i = 0;
for (; dst_prev != &rt->u.dst; dst_prev = dst_prev->child) {
struct xfrm_dst *x = (struct xfrm_dst*)dst_prev;
dst_prev->xfrm = xfrm[i++];
dst_prev->dev = rt->u.dst.dev;
if (rt->u.dst.dev)
dev_hold(rt->u.dst.dev);
dst_prev->obsolete = -1;
dst_prev->flags |= DST_HOST;
dst_prev->lastuse = jiffies;
dst_prev->header_len = header_len;
dst_prev->trailer_len = trailer_len;
memcpy(&dst_prev->metrics, &x->route->metrics, sizeof(dst_prev->metrics));
/* Copy neighbour for reachability confirmation */
dst_prev->neighbour = neigh_clone(rt->u.dst.neighbour);
dst_prev->input = rt->u.dst.input;
dst_prev->output = xfrm6_output;
/* Sheit... I remember I did this right. Apparently,
* it was magically lost, so this code needs audit */
x->u.rt6.rt6i_flags = rt0->rt6i_flags&(RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL);
x->u.rt6.rt6i_metric = rt0->rt6i_metric;
x->u.rt6.rt6i_node = rt0->rt6i_node;
x->u.rt6.rt6i_gateway = rt0->rt6i_gateway;
memcpy(&x->u.rt6.rt6i_gateway, &rt0->rt6i_gateway, sizeof(x->u.rt6.rt6i_gateway));
x->u.rt6.rt6i_dst = rt0->rt6i_dst;
x->u.rt6.rt6i_src = rt0->rt6i_src;
x->u.rt6.rt6i_idev = rt0->rt6i_idev;
in6_dev_hold(rt0->rt6i_idev);
header_len -= x->u.dst.xfrm->props.header_len;
trailer_len -= x->u.dst.xfrm->props.trailer_len;
}
xfrm_init_pmtu(dst);
return 0;
error:
if (dst)
dst_free(dst);
return err;
}
static inline void
_decode_session6(struct sk_buff *skb, struct flowi *fl)
{
u16 offset = skb->h.raw - skb->nh.raw;
struct ipv6hdr *hdr = skb->nh.ipv6h;
struct ipv6_opt_hdr *exthdr;
u8 nexthdr = skb->nh.raw[IP6CB(skb)->nhoff];
memset(fl, 0, sizeof(struct flowi));
ipv6_addr_copy(&fl->fl6_dst, &hdr->daddr);
ipv6_addr_copy(&fl->fl6_src, &hdr->saddr);
while (pskb_may_pull(skb, skb->nh.raw + offset + 1 - skb->data)) {
exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
switch (nexthdr) {
case NEXTHDR_ROUTING:
case NEXTHDR_HOP:
case NEXTHDR_DEST:
offset += ipv6_optlen(exthdr);
nexthdr = exthdr->nexthdr;
exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset);
break;
case IPPROTO_UDP:
case IPPROTO_TCP:
case IPPROTO_SCTP:
case IPPROTO_DCCP:
if (pskb_may_pull(skb, skb->nh.raw + offset + 4 - skb->data)) {
u16 *ports = (u16 *)exthdr;
fl->fl_ip_sport = ports[0];
fl->fl_ip_dport = ports[1];
}
fl->proto = nexthdr;
return;
case IPPROTO_ICMPV6:
if (pskb_may_pull(skb, skb->nh.raw + offset + 2 - skb->data)) {
u8 *icmp = (u8 *)exthdr;
fl->fl_icmp_type = icmp[0];
fl->fl_icmp_code = icmp[1];
}
fl->proto = nexthdr;
return;
/* XXX Why are there these headers? */
case IPPROTO_AH:
case IPPROTO_ESP:
case IPPROTO_COMP:
default:
fl->fl_ipsec_spi = 0;
fl->proto = nexthdr;
return;
};
}
}
static inline int xfrm6_garbage_collect(void)
{
xfrm6_policy_afinfo.garbage_collect();
return (atomic_read(&xfrm6_dst_ops.entries) > xfrm6_dst_ops.gc_thresh*2);
}
static void xfrm6_update_pmtu(struct dst_entry *dst, u32 mtu)
{
struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
struct dst_entry *path = xdst->route;
path->ops->update_pmtu(path, mtu);
}
static void xfrm6_dst_destroy(struct dst_entry *dst)
{
struct xfrm_dst *xdst = (struct xfrm_dst *)dst;
if (likely(xdst->u.rt6.rt6i_idev))
in6_dev_put(xdst->u.rt6.rt6i_idev);
xfrm_dst_destroy(xdst);
}
static void xfrm6_dst_ifdown(struct dst_entry *dst, struct net_device *dev,
int unregister)
{
struct xfrm_dst *xdst;
if (!unregister)
return;
xdst = (struct xfrm_dst *)dst;
if (xdst->u.rt6.rt6i_idev->dev == dev) {
struct inet6_dev *loopback_idev = in6_dev_get(&loopback_dev);
BUG_ON(!loopback_idev);
do {
in6_dev_put(xdst->u.rt6.rt6i_idev);
xdst->u.rt6.rt6i_idev = loopback_idev;
in6_dev_hold(loopback_idev);
xdst = (struct xfrm_dst *)xdst->u.dst.child;
} while (xdst->u.dst.xfrm);
__in6_dev_put(loopback_idev);
}
xfrm_dst_ifdown(dst, dev);
}
static struct dst_ops xfrm6_dst_ops = {
.family = AF_INET6,
.protocol = __constant_htons(ETH_P_IPV6),
.gc = xfrm6_garbage_collect,
.update_pmtu = xfrm6_update_pmtu,
.destroy = xfrm6_dst_destroy,
.ifdown = xfrm6_dst_ifdown,
.gc_thresh = 1024,
.entry_size = sizeof(struct xfrm_dst),
};
static struct xfrm_policy_afinfo xfrm6_policy_afinfo = {
.family = AF_INET6,
.dst_ops = &xfrm6_dst_ops,
.dst_lookup = xfrm6_dst_lookup,
.find_bundle = __xfrm6_find_bundle,
.bundle_create = __xfrm6_bundle_create,
.decode_session = _decode_session6,
};
static void __init xfrm6_policy_init(void)
{
xfrm_policy_register_afinfo(&xfrm6_policy_afinfo);
}
static void xfrm6_policy_fini(void)
{
xfrm_policy_unregister_afinfo(&xfrm6_policy_afinfo);
}
void __init xfrm6_init(void)
{
xfrm6_policy_init();
xfrm6_state_init();
}
void xfrm6_fini(void)
{
//xfrm6_input_fini();
xfrm6_policy_fini();
xfrm6_state_fini();
}