| /* | 
 |  * 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 <asm/bug.h> | 
 | #include <linux/compiler.h> | 
 | #include <linux/config.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 struct xfrm_type_map xfrm6_type_map = { .lock = RW_LOCK_UNLOCKED }; | 
 |  | 
 | 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 = sizeof(struct ipv6hdr); | 
 | 	struct ipv6hdr *hdr = skb->nh.ipv6h; | 
 | 	struct ipv6_opt_hdr *exthdr = (struct ipv6_opt_hdr*)(skb->nh.raw + offset); | 
 | 	u8 nexthdr = skb->nh.ipv6h->nexthdr; | 
 |  | 
 | 	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)) { | 
 | 		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) | 
 | { | 
 | 	read_lock(&xfrm6_policy_afinfo.lock); | 
 | 	xfrm6_policy_afinfo.garbage_collect(); | 
 | 	read_unlock(&xfrm6_policy_afinfo.lock); | 
 | 	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, | 
 | 	.lock = 		RW_LOCK_UNLOCKED, | 
 | 	.type_map = 		&xfrm6_type_map, | 
 | 	.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(); | 
 | } |