/*
* 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) {
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();
}
