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-rw-r--r--net/ipv4/xfrm4_policy.c281
1 files changed, 281 insertions, 0 deletions
diff --git a/net/ipv4/xfrm4_policy.c b/net/ipv4/xfrm4_policy.c
new file mode 100644
index 000000000000..7fe2afd2e669
--- /dev/null
+++ b/net/ipv4/xfrm4_policy.c
@@ -0,0 +1,281 @@
+/*
+ * xfrm4_policy.c
+ *
+ * Changes:
+ * Kazunori MIYAZAWA @USAGI
+ * YOSHIFUJI Hideaki @USAGI
+ * Split up af-specific portion
+ *
+ */
+
+#include <linux/config.h>
+#include <net/xfrm.h>
+#include <net/ip.h>
+
+static struct dst_ops xfrm4_dst_ops;
+static struct xfrm_policy_afinfo xfrm4_policy_afinfo;
+
+static struct xfrm_type_map xfrm4_type_map = { .lock = RW_LOCK_UNLOCKED };
+
+static int xfrm4_dst_lookup(struct xfrm_dst **dst, struct flowi *fl)
+{
+ return __ip_route_output_key((struct rtable**)dst, fl);
+}
+
+static struct dst_entry *
+__xfrm4_find_bundle(struct flowi *fl, struct xfrm_policy *policy)
+{
+ struct dst_entry *dst;
+
+ read_lock_bh(&policy->lock);
+ for (dst = policy->bundles; dst; dst = dst->next) {
+ struct xfrm_dst *xdst = (struct xfrm_dst*)dst;
+ if (xdst->u.rt.fl.oif == fl->oif && /*XXX*/
+ xdst->u.rt.fl.fl4_dst == fl->fl4_dst &&
+ xdst->u.rt.fl.fl4_src == fl->fl4_src &&
+ xfrm_bundle_ok(xdst, fl, AF_INET)) {
+ 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
+__xfrm4_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 rtable *rt0 = (struct rtable*)(*dst_p);
+ struct rtable *rt = rt0;
+ u32 remote = fl->fl4_dst;
+ u32 local = fl->fl4_src;
+ struct flowi fl_tunnel = {
+ .nl_u = {
+ .ip4_u = {
+ .saddr = local,
+ .daddr = remote
+ }
+ }
+ };
+ int i;
+ int err;
+ 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(&xfrm4_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;
+
+ dst1->next = dst_prev;
+ dst_prev = dst1;
+ if (xfrm[i]->props.mode) {
+ remote = xfrm[i]->id.daddr.a4;
+ local = xfrm[i]->props.saddr.a4;
+ tunnel = 1;
+ }
+ header_len += xfrm[i]->props.header_len;
+ trailer_len += xfrm[i]->props.trailer_len;
+
+ if (tunnel) {
+ fl_tunnel.fl4_src = local;
+ fl_tunnel.fl4_dst = remote;
+ err = xfrm_dst_lookup((struct xfrm_dst **)&rt,
+ &fl_tunnel, AF_INET);
+ if (err)
+ goto error;
+ } else
+ dst_hold(&rt->u.dst);
+ }
+
+ dst_prev->child = &rt->u.dst;
+ dst->path = &rt->u.dst;
+
+ *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;
+ x->u.rt.fl = *fl;
+
+ 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 neighbout for reachability confirmation */
+ dst_prev->neighbour = neigh_clone(rt->u.dst.neighbour);
+ dst_prev->input = rt->u.dst.input;
+ dst_prev->output = xfrm4_output;
+ if (rt->peer)
+ atomic_inc(&rt->peer->refcnt);
+ x->u.rt.peer = rt->peer;
+ /* Sheit... I remember I did this right. Apparently,
+ * it was magically lost, so this code needs audit */
+ x->u.rt.rt_flags = rt0->rt_flags&(RTCF_BROADCAST|RTCF_MULTICAST|RTCF_LOCAL);
+ x->u.rt.rt_type = rt->rt_type;
+ x->u.rt.rt_src = rt0->rt_src;
+ x->u.rt.rt_dst = rt0->rt_dst;
+ x->u.rt.rt_gateway = rt->rt_gateway;
+ x->u.rt.rt_spec_dst = rt0->rt_spec_dst;
+ 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 void
+_decode_session4(struct sk_buff *skb, struct flowi *fl)
+{
+ struct iphdr *iph = skb->nh.iph;
+ u8 *xprth = skb->nh.raw + iph->ihl*4;
+
+ memset(fl, 0, sizeof(struct flowi));
+ if (!(iph->frag_off & htons(IP_MF | IP_OFFSET))) {
+ switch (iph->protocol) {
+ case IPPROTO_UDP:
+ case IPPROTO_TCP:
+ case IPPROTO_SCTP:
+ if (pskb_may_pull(skb, xprth + 4 - skb->data)) {
+ u16 *ports = (u16 *)xprth;
+
+ fl->fl_ip_sport = ports[0];
+ fl->fl_ip_dport = ports[1];
+ }
+ break;
+
+ case IPPROTO_ICMP:
+ if (pskb_may_pull(skb, xprth + 2 - skb->data)) {
+ u8 *icmp = xprth;
+
+ fl->fl_icmp_type = icmp[0];
+ fl->fl_icmp_code = icmp[1];
+ }
+ break;
+
+ case IPPROTO_ESP:
+ if (pskb_may_pull(skb, xprth + 4 - skb->data)) {
+ u32 *ehdr = (u32 *)xprth;
+
+ fl->fl_ipsec_spi = ehdr[0];
+ }
+ break;
+
+ case IPPROTO_AH:
+ if (pskb_may_pull(skb, xprth + 8 - skb->data)) {
+ u32 *ah_hdr = (u32*)xprth;
+
+ fl->fl_ipsec_spi = ah_hdr[1];
+ }
+ break;
+
+ case IPPROTO_COMP:
+ if (pskb_may_pull(skb, xprth + 4 - skb->data)) {
+ u16 *ipcomp_hdr = (u16 *)xprth;
+
+ fl->fl_ipsec_spi = ntohl(ntohs(ipcomp_hdr[1]));
+ }
+ break;
+ default:
+ fl->fl_ipsec_spi = 0;
+ break;
+ };
+ }
+ fl->proto = iph->protocol;
+ fl->fl4_dst = iph->daddr;
+ fl->fl4_src = iph->saddr;
+}
+
+static inline int xfrm4_garbage_collect(void)
+{
+ read_lock(&xfrm4_policy_afinfo.lock);
+ xfrm4_policy_afinfo.garbage_collect();
+ read_unlock(&xfrm4_policy_afinfo.lock);
+ return (atomic_read(&xfrm4_dst_ops.entries) > xfrm4_dst_ops.gc_thresh*2);
+}
+
+static void xfrm4_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 struct dst_ops xfrm4_dst_ops = {
+ .family = AF_INET,
+ .protocol = __constant_htons(ETH_P_IP),
+ .gc = xfrm4_garbage_collect,
+ .update_pmtu = xfrm4_update_pmtu,
+ .gc_thresh = 1024,
+ .entry_size = sizeof(struct xfrm_dst),
+};
+
+static struct xfrm_policy_afinfo xfrm4_policy_afinfo = {
+ .family = AF_INET,
+ .lock = RW_LOCK_UNLOCKED,
+ .type_map = &xfrm4_type_map,
+ .dst_ops = &xfrm4_dst_ops,
+ .dst_lookup = xfrm4_dst_lookup,
+ .find_bundle = __xfrm4_find_bundle,
+ .bundle_create = __xfrm4_bundle_create,
+ .decode_session = _decode_session4,
+};
+
+static void __init xfrm4_policy_init(void)
+{
+ xfrm_policy_register_afinfo(&xfrm4_policy_afinfo);
+}
+
+static void __exit xfrm4_policy_fini(void)
+{
+ xfrm_policy_unregister_afinfo(&xfrm4_policy_afinfo);
+}
+
+void __init xfrm4_init(void)
+{
+ xfrm4_state_init();
+ xfrm4_policy_init();
+}
+