| #include <linux/types.h> | 
 | #include <linux/skbuff.h> | 
 | #include <linux/socket.h> | 
 | #include <linux/sysctl.h> | 
 | #include <linux/net.h> | 
 | #include <linux/module.h> | 
 | #include <linux/if_arp.h> | 
 | #include <linux/ipv6.h> | 
 | #include <linux/mpls.h> | 
 | #include <linux/nospec.h> | 
 | #include <linux/vmalloc.h> | 
 | #include <net/ip.h> | 
 | #include <net/dst.h> | 
 | #include <net/sock.h> | 
 | #include <net/arp.h> | 
 | #include <net/ip_fib.h> | 
 | #include <net/netevent.h> | 
 | #include <net/netns/generic.h> | 
 | #if IS_ENABLED(CONFIG_IPV6) | 
 | #include <net/ipv6.h> | 
 | #include <net/addrconf.h> | 
 | #endif | 
 | #include <net/nexthop.h> | 
 | #include "internal.h" | 
 |  | 
 | /* Maximum number of labels to look ahead at when selecting a path of | 
 |  * a multipath route | 
 |  */ | 
 | #define MAX_MP_SELECT_LABELS 4 | 
 |  | 
 | #define MPLS_NEIGH_TABLE_UNSPEC (NEIGH_LINK_TABLE + 1) | 
 |  | 
 | static int zero = 0; | 
 | static int label_limit = (1 << 20) - 1; | 
 |  | 
 | static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt, | 
 | 		       struct nlmsghdr *nlh, struct net *net, u32 portid, | 
 | 		       unsigned int nlm_flags); | 
 |  | 
 | static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned index) | 
 | { | 
 | 	struct mpls_route *rt = NULL; | 
 |  | 
 | 	if (index < net->mpls.platform_labels) { | 
 | 		struct mpls_route __rcu **platform_label = | 
 | 			rcu_dereference(net->mpls.platform_label); | 
 | 		rt = rcu_dereference(platform_label[index]); | 
 | 	} | 
 | 	return rt; | 
 | } | 
 |  | 
 | static inline struct mpls_dev *mpls_dev_get(const struct net_device *dev) | 
 | { | 
 | 	return rcu_dereference_rtnl(dev->mpls_ptr); | 
 | } | 
 |  | 
 | bool mpls_output_possible(const struct net_device *dev) | 
 | { | 
 | 	return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev); | 
 | } | 
 | EXPORT_SYMBOL_GPL(mpls_output_possible); | 
 |  | 
 | static u8 *__mpls_nh_via(struct mpls_route *rt, struct mpls_nh *nh) | 
 | { | 
 | 	u8 *nh0_via = PTR_ALIGN((u8 *)&rt->rt_nh[rt->rt_nhn], VIA_ALEN_ALIGN); | 
 | 	int nh_index = nh - rt->rt_nh; | 
 |  | 
 | 	return nh0_via + rt->rt_max_alen * nh_index; | 
 | } | 
 |  | 
 | static const u8 *mpls_nh_via(const struct mpls_route *rt, | 
 | 			     const struct mpls_nh *nh) | 
 | { | 
 | 	return __mpls_nh_via((struct mpls_route *)rt, (struct mpls_nh *)nh); | 
 | } | 
 |  | 
 | static unsigned int mpls_nh_header_size(const struct mpls_nh *nh) | 
 | { | 
 | 	/* The size of the layer 2.5 labels to be added for this route */ | 
 | 	return nh->nh_labels * sizeof(struct mpls_shim_hdr); | 
 | } | 
 |  | 
 | unsigned int mpls_dev_mtu(const struct net_device *dev) | 
 | { | 
 | 	/* The amount of data the layer 2 frame can hold */ | 
 | 	return dev->mtu; | 
 | } | 
 | EXPORT_SYMBOL_GPL(mpls_dev_mtu); | 
 |  | 
 | bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu) | 
 | { | 
 | 	if (skb->len <= mtu) | 
 | 		return false; | 
 |  | 
 | 	if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu)) | 
 | 		return false; | 
 |  | 
 | 	return true; | 
 | } | 
 | EXPORT_SYMBOL_GPL(mpls_pkt_too_big); | 
 |  | 
 | static u32 mpls_multipath_hash(struct mpls_route *rt, struct sk_buff *skb) | 
 | { | 
 | 	struct mpls_entry_decoded dec; | 
 | 	unsigned int mpls_hdr_len = 0; | 
 | 	struct mpls_shim_hdr *hdr; | 
 | 	bool eli_seen = false; | 
 | 	int label_index; | 
 | 	u32 hash = 0; | 
 |  | 
 | 	for (label_index = 0; label_index < MAX_MP_SELECT_LABELS; | 
 | 	     label_index++) { | 
 | 		mpls_hdr_len += sizeof(*hdr); | 
 | 		if (!pskb_may_pull(skb, mpls_hdr_len)) | 
 | 			break; | 
 |  | 
 | 		/* Read and decode the current label */ | 
 | 		hdr = mpls_hdr(skb) + label_index; | 
 | 		dec = mpls_entry_decode(hdr); | 
 |  | 
 | 		/* RFC6790 - reserved labels MUST NOT be used as keys | 
 | 		 * for the load-balancing function | 
 | 		 */ | 
 | 		if (likely(dec.label >= MPLS_LABEL_FIRST_UNRESERVED)) { | 
 | 			hash = jhash_1word(dec.label, hash); | 
 |  | 
 | 			/* The entropy label follows the entropy label | 
 | 			 * indicator, so this means that the entropy | 
 | 			 * label was just added to the hash - no need to | 
 | 			 * go any deeper either in the label stack or in the | 
 | 			 * payload | 
 | 			 */ | 
 | 			if (eli_seen) | 
 | 				break; | 
 | 		} else if (dec.label == MPLS_LABEL_ENTROPY) { | 
 | 			eli_seen = true; | 
 | 		} | 
 |  | 
 | 		if (!dec.bos) | 
 | 			continue; | 
 |  | 
 | 		/* found bottom label; does skb have room for a header? */ | 
 | 		if (pskb_may_pull(skb, mpls_hdr_len + sizeof(struct iphdr))) { | 
 | 			const struct iphdr *v4hdr; | 
 |  | 
 | 			v4hdr = (const struct iphdr *)(hdr + 1); | 
 | 			if (v4hdr->version == 4) { | 
 | 				hash = jhash_3words(ntohl(v4hdr->saddr), | 
 | 						    ntohl(v4hdr->daddr), | 
 | 						    v4hdr->protocol, hash); | 
 | 			} else if (v4hdr->version == 6 && | 
 | 				   pskb_may_pull(skb, mpls_hdr_len + | 
 | 						 sizeof(struct ipv6hdr))) { | 
 | 				const struct ipv6hdr *v6hdr; | 
 |  | 
 | 				v6hdr = (const struct ipv6hdr *)(hdr + 1); | 
 | 				hash = __ipv6_addr_jhash(&v6hdr->saddr, hash); | 
 | 				hash = __ipv6_addr_jhash(&v6hdr->daddr, hash); | 
 | 				hash = jhash_1word(v6hdr->nexthdr, hash); | 
 | 			} | 
 | 		} | 
 |  | 
 | 		break; | 
 | 	} | 
 |  | 
 | 	return hash; | 
 | } | 
 |  | 
 | static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt, | 
 | 					     struct sk_buff *skb) | 
 | { | 
 | 	int alive = ACCESS_ONCE(rt->rt_nhn_alive); | 
 | 	u32 hash = 0; | 
 | 	int nh_index = 0; | 
 | 	int n = 0; | 
 |  | 
 | 	/* No need to look further into packet if there's only | 
 | 	 * one path | 
 | 	 */ | 
 | 	if (rt->rt_nhn == 1) | 
 | 		goto out; | 
 |  | 
 | 	if (alive <= 0) | 
 | 		return NULL; | 
 |  | 
 | 	hash = mpls_multipath_hash(rt, skb); | 
 | 	nh_index = hash % alive; | 
 | 	if (alive == rt->rt_nhn) | 
 | 		goto out; | 
 | 	for_nexthops(rt) { | 
 | 		if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) | 
 | 			continue; | 
 | 		if (n == nh_index) | 
 | 			return nh; | 
 | 		n++; | 
 | 	} endfor_nexthops(rt); | 
 |  | 
 | out: | 
 | 	return &rt->rt_nh[nh_index]; | 
 | } | 
 |  | 
 | static bool mpls_egress(struct mpls_route *rt, struct sk_buff *skb, | 
 | 			struct mpls_entry_decoded dec) | 
 | { | 
 | 	enum mpls_payload_type payload_type; | 
 | 	bool success = false; | 
 |  | 
 | 	/* The IPv4 code below accesses through the IPv4 header | 
 | 	 * checksum, which is 12 bytes into the packet. | 
 | 	 * The IPv6 code below accesses through the IPv6 hop limit | 
 | 	 * which is 8 bytes into the packet. | 
 | 	 * | 
 | 	 * For all supported cases there should always be at least 12 | 
 | 	 * bytes of packet data present.  The IPv4 header is 20 bytes | 
 | 	 * without options and the IPv6 header is always 40 bytes | 
 | 	 * long. | 
 | 	 */ | 
 | 	if (!pskb_may_pull(skb, 12)) | 
 | 		return false; | 
 |  | 
 | 	payload_type = rt->rt_payload_type; | 
 | 	if (payload_type == MPT_UNSPEC) | 
 | 		payload_type = ip_hdr(skb)->version; | 
 |  | 
 | 	switch (payload_type) { | 
 | 	case MPT_IPV4: { | 
 | 		struct iphdr *hdr4 = ip_hdr(skb); | 
 | 		skb->protocol = htons(ETH_P_IP); | 
 | 		csum_replace2(&hdr4->check, | 
 | 			      htons(hdr4->ttl << 8), | 
 | 			      htons(dec.ttl << 8)); | 
 | 		hdr4->ttl = dec.ttl; | 
 | 		success = true; | 
 | 		break; | 
 | 	} | 
 | 	case MPT_IPV6: { | 
 | 		struct ipv6hdr *hdr6 = ipv6_hdr(skb); | 
 | 		skb->protocol = htons(ETH_P_IPV6); | 
 | 		hdr6->hop_limit = dec.ttl; | 
 | 		success = true; | 
 | 		break; | 
 | 	} | 
 | 	case MPT_UNSPEC: | 
 | 		break; | 
 | 	} | 
 |  | 
 | 	return success; | 
 | } | 
 |  | 
 | static int mpls_forward(struct sk_buff *skb, struct net_device *dev, | 
 | 			struct packet_type *pt, struct net_device *orig_dev) | 
 | { | 
 | 	struct net *net = dev_net(dev); | 
 | 	struct mpls_shim_hdr *hdr; | 
 | 	struct mpls_route *rt; | 
 | 	struct mpls_nh *nh; | 
 | 	struct mpls_entry_decoded dec; | 
 | 	struct net_device *out_dev; | 
 | 	struct mpls_dev *mdev; | 
 | 	unsigned int hh_len; | 
 | 	unsigned int new_header_size; | 
 | 	unsigned int mtu; | 
 | 	int err; | 
 |  | 
 | 	/* Careful this entire function runs inside of an rcu critical section */ | 
 |  | 
 | 	mdev = mpls_dev_get(dev); | 
 | 	if (!mdev || !mdev->input_enabled) | 
 | 		goto drop; | 
 |  | 
 | 	if (skb->pkt_type != PACKET_HOST) | 
 | 		goto drop; | 
 |  | 
 | 	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL) | 
 | 		goto drop; | 
 |  | 
 | 	if (!pskb_may_pull(skb, sizeof(*hdr))) | 
 | 		goto drop; | 
 |  | 
 | 	/* Read and decode the label */ | 
 | 	hdr = mpls_hdr(skb); | 
 | 	dec = mpls_entry_decode(hdr); | 
 |  | 
 | 	rt = mpls_route_input_rcu(net, dec.label); | 
 | 	if (!rt) | 
 | 		goto drop; | 
 |  | 
 | 	nh = mpls_select_multipath(rt, skb); | 
 | 	if (!nh) | 
 | 		goto drop; | 
 |  | 
 | 	/* Find the output device */ | 
 | 	out_dev = rcu_dereference(nh->nh_dev); | 
 | 	if (!mpls_output_possible(out_dev)) | 
 | 		goto drop; | 
 |  | 
 | 	/* Pop the label */ | 
 | 	skb_pull(skb, sizeof(*hdr)); | 
 | 	skb_reset_network_header(skb); | 
 |  | 
 | 	skb_orphan(skb); | 
 |  | 
 | 	if (skb_warn_if_lro(skb)) | 
 | 		goto drop; | 
 |  | 
 | 	skb_forward_csum(skb); | 
 |  | 
 | 	/* Verify ttl is valid */ | 
 | 	if (dec.ttl <= 1) | 
 | 		goto drop; | 
 | 	dec.ttl -= 1; | 
 |  | 
 | 	/* Verify the destination can hold the packet */ | 
 | 	new_header_size = mpls_nh_header_size(nh); | 
 | 	mtu = mpls_dev_mtu(out_dev); | 
 | 	if (mpls_pkt_too_big(skb, mtu - new_header_size)) | 
 | 		goto drop; | 
 |  | 
 | 	hh_len = LL_RESERVED_SPACE(out_dev); | 
 | 	if (!out_dev->header_ops) | 
 | 		hh_len = 0; | 
 |  | 
 | 	/* Ensure there is enough space for the headers in the skb */ | 
 | 	if (skb_cow(skb, hh_len + new_header_size)) | 
 | 		goto drop; | 
 |  | 
 | 	skb->dev = out_dev; | 
 | 	skb->protocol = htons(ETH_P_MPLS_UC); | 
 |  | 
 | 	if (unlikely(!new_header_size && dec.bos)) { | 
 | 		/* Penultimate hop popping */ | 
 | 		if (!mpls_egress(rt, skb, dec)) | 
 | 			goto drop; | 
 | 	} else { | 
 | 		bool bos; | 
 | 		int i; | 
 | 		skb_push(skb, new_header_size); | 
 | 		skb_reset_network_header(skb); | 
 | 		/* Push the new labels */ | 
 | 		hdr = mpls_hdr(skb); | 
 | 		bos = dec.bos; | 
 | 		for (i = nh->nh_labels - 1; i >= 0; i--) { | 
 | 			hdr[i] = mpls_entry_encode(nh->nh_label[i], | 
 | 						   dec.ttl, 0, bos); | 
 | 			bos = false; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	/* If via wasn't specified then send out using device address */ | 
 | 	if (nh->nh_via_table == MPLS_NEIGH_TABLE_UNSPEC) | 
 | 		err = neigh_xmit(NEIGH_LINK_TABLE, out_dev, | 
 | 				 out_dev->dev_addr, skb); | 
 | 	else | 
 | 		err = neigh_xmit(nh->nh_via_table, out_dev, | 
 | 				 mpls_nh_via(rt, nh), skb); | 
 | 	if (err) | 
 | 		net_dbg_ratelimited("%s: packet transmission failed: %d\n", | 
 | 				    __func__, err); | 
 | 	return 0; | 
 |  | 
 | drop: | 
 | 	kfree_skb(skb); | 
 | 	return NET_RX_DROP; | 
 | } | 
 |  | 
 | static struct packet_type mpls_packet_type __read_mostly = { | 
 | 	.type = cpu_to_be16(ETH_P_MPLS_UC), | 
 | 	.func = mpls_forward, | 
 | }; | 
 |  | 
 | static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = { | 
 | 	[RTA_DST]		= { .type = NLA_U32 }, | 
 | 	[RTA_OIF]		= { .type = NLA_U32 }, | 
 | }; | 
 |  | 
 | struct mpls_route_config { | 
 | 	u32			rc_protocol; | 
 | 	u32			rc_ifindex; | 
 | 	u8			rc_via_table; | 
 | 	u8			rc_via_alen; | 
 | 	u8			rc_via[MAX_VIA_ALEN]; | 
 | 	u32			rc_label; | 
 | 	u8			rc_output_labels; | 
 | 	u32			rc_output_label[MAX_NEW_LABELS]; | 
 | 	u32			rc_nlflags; | 
 | 	enum mpls_payload_type	rc_payload_type; | 
 | 	struct nl_info		rc_nlinfo; | 
 | 	struct rtnexthop	*rc_mp; | 
 | 	int			rc_mp_len; | 
 | }; | 
 |  | 
 | static struct mpls_route *mpls_rt_alloc(int num_nh, u8 max_alen) | 
 | { | 
 | 	u8 max_alen_aligned = ALIGN(max_alen, VIA_ALEN_ALIGN); | 
 | 	struct mpls_route *rt; | 
 |  | 
 | 	rt = kzalloc(ALIGN(sizeof(*rt) + num_nh * sizeof(*rt->rt_nh), | 
 | 			   VIA_ALEN_ALIGN) + | 
 | 		     num_nh * max_alen_aligned, | 
 | 		     GFP_KERNEL); | 
 | 	if (rt) { | 
 | 		rt->rt_nhn = num_nh; | 
 | 		rt->rt_nhn_alive = num_nh; | 
 | 		rt->rt_max_alen = max_alen_aligned; | 
 | 	} | 
 |  | 
 | 	return rt; | 
 | } | 
 |  | 
 | static void mpls_rt_free(struct mpls_route *rt) | 
 | { | 
 | 	if (rt) | 
 | 		kfree_rcu(rt, rt_rcu); | 
 | } | 
 |  | 
 | static void mpls_notify_route(struct net *net, unsigned index, | 
 | 			      struct mpls_route *old, struct mpls_route *new, | 
 | 			      const struct nl_info *info) | 
 | { | 
 | 	struct nlmsghdr *nlh = info ? info->nlh : NULL; | 
 | 	unsigned portid = info ? info->portid : 0; | 
 | 	int event = new ? RTM_NEWROUTE : RTM_DELROUTE; | 
 | 	struct mpls_route *rt = new ? new : old; | 
 | 	unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0; | 
 | 	/* Ignore reserved labels for now */ | 
 | 	if (rt && (index >= MPLS_LABEL_FIRST_UNRESERVED)) | 
 | 		rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags); | 
 | } | 
 |  | 
 | static void mpls_route_update(struct net *net, unsigned index, | 
 | 			      struct mpls_route *new, | 
 | 			      const struct nl_info *info) | 
 | { | 
 | 	struct mpls_route __rcu **platform_label; | 
 | 	struct mpls_route *rt; | 
 |  | 
 | 	ASSERT_RTNL(); | 
 |  | 
 | 	platform_label = rtnl_dereference(net->mpls.platform_label); | 
 | 	rt = rtnl_dereference(platform_label[index]); | 
 | 	rcu_assign_pointer(platform_label[index], new); | 
 |  | 
 | 	mpls_notify_route(net, index, rt, new, info); | 
 |  | 
 | 	/* If we removed a route free it now */ | 
 | 	mpls_rt_free(rt); | 
 | } | 
 |  | 
 | static unsigned find_free_label(struct net *net) | 
 | { | 
 | 	struct mpls_route __rcu **platform_label; | 
 | 	size_t platform_labels; | 
 | 	unsigned index; | 
 |  | 
 | 	platform_label = rtnl_dereference(net->mpls.platform_label); | 
 | 	platform_labels = net->mpls.platform_labels; | 
 | 	for (index = MPLS_LABEL_FIRST_UNRESERVED; index < platform_labels; | 
 | 	     index++) { | 
 | 		if (!rtnl_dereference(platform_label[index])) | 
 | 			return index; | 
 | 	} | 
 | 	return LABEL_NOT_SPECIFIED; | 
 | } | 
 |  | 
 | #if IS_ENABLED(CONFIG_INET) | 
 | static struct net_device *inet_fib_lookup_dev(struct net *net, | 
 | 					      const void *addr) | 
 | { | 
 | 	struct net_device *dev; | 
 | 	struct rtable *rt; | 
 | 	struct in_addr daddr; | 
 |  | 
 | 	memcpy(&daddr, addr, sizeof(struct in_addr)); | 
 | 	rt = ip_route_output(net, daddr.s_addr, 0, 0, 0); | 
 | 	if (IS_ERR(rt)) | 
 | 		return ERR_CAST(rt); | 
 |  | 
 | 	dev = rt->dst.dev; | 
 | 	dev_hold(dev); | 
 |  | 
 | 	ip_rt_put(rt); | 
 |  | 
 | 	return dev; | 
 | } | 
 | #else | 
 | static struct net_device *inet_fib_lookup_dev(struct net *net, | 
 | 					      const void *addr) | 
 | { | 
 | 	return ERR_PTR(-EAFNOSUPPORT); | 
 | } | 
 | #endif | 
 |  | 
 | #if IS_ENABLED(CONFIG_IPV6) | 
 | static struct net_device *inet6_fib_lookup_dev(struct net *net, | 
 | 					       const void *addr) | 
 | { | 
 | 	struct net_device *dev; | 
 | 	struct dst_entry *dst; | 
 | 	struct flowi6 fl6; | 
 | 	int err; | 
 |  | 
 | 	if (!ipv6_stub) | 
 | 		return ERR_PTR(-EAFNOSUPPORT); | 
 |  | 
 | 	memset(&fl6, 0, sizeof(fl6)); | 
 | 	memcpy(&fl6.daddr, addr, sizeof(struct in6_addr)); | 
 | 	err = ipv6_stub->ipv6_dst_lookup(net, NULL, &dst, &fl6); | 
 | 	if (err) | 
 | 		return ERR_PTR(err); | 
 |  | 
 | 	dev = dst->dev; | 
 | 	dev_hold(dev); | 
 | 	dst_release(dst); | 
 |  | 
 | 	return dev; | 
 | } | 
 | #else | 
 | static struct net_device *inet6_fib_lookup_dev(struct net *net, | 
 | 					       const void *addr) | 
 | { | 
 | 	return ERR_PTR(-EAFNOSUPPORT); | 
 | } | 
 | #endif | 
 |  | 
 | static struct net_device *find_outdev(struct net *net, | 
 | 				      struct mpls_route *rt, | 
 | 				      struct mpls_nh *nh, int oif) | 
 | { | 
 | 	struct net_device *dev = NULL; | 
 |  | 
 | 	if (!oif) { | 
 | 		switch (nh->nh_via_table) { | 
 | 		case NEIGH_ARP_TABLE: | 
 | 			dev = inet_fib_lookup_dev(net, mpls_nh_via(rt, nh)); | 
 | 			break; | 
 | 		case NEIGH_ND_TABLE: | 
 | 			dev = inet6_fib_lookup_dev(net, mpls_nh_via(rt, nh)); | 
 | 			break; | 
 | 		case NEIGH_LINK_TABLE: | 
 | 			break; | 
 | 		} | 
 | 	} else { | 
 | 		dev = dev_get_by_index(net, oif); | 
 | 	} | 
 |  | 
 | 	if (!dev) | 
 | 		return ERR_PTR(-ENODEV); | 
 |  | 
 | 	if (IS_ERR(dev)) | 
 | 		return dev; | 
 |  | 
 | 	/* The caller is holding rtnl anyways, so release the dev reference */ | 
 | 	dev_put(dev); | 
 |  | 
 | 	return dev; | 
 | } | 
 |  | 
 | static int mpls_nh_assign_dev(struct net *net, struct mpls_route *rt, | 
 | 			      struct mpls_nh *nh, int oif) | 
 | { | 
 | 	struct net_device *dev = NULL; | 
 | 	int err = -ENODEV; | 
 |  | 
 | 	dev = find_outdev(net, rt, nh, oif); | 
 | 	if (IS_ERR(dev)) { | 
 | 		err = PTR_ERR(dev); | 
 | 		dev = NULL; | 
 | 		goto errout; | 
 | 	} | 
 |  | 
 | 	/* Ensure this is a supported device */ | 
 | 	err = -EINVAL; | 
 | 	if (!mpls_dev_get(dev)) | 
 | 		goto errout; | 
 |  | 
 | 	if ((nh->nh_via_table == NEIGH_LINK_TABLE) && | 
 | 	    (dev->addr_len != nh->nh_via_alen)) | 
 | 		goto errout; | 
 |  | 
 | 	RCU_INIT_POINTER(nh->nh_dev, dev); | 
 |  | 
 | 	if (!(dev->flags & IFF_UP)) { | 
 | 		nh->nh_flags |= RTNH_F_DEAD; | 
 | 	} else { | 
 | 		unsigned int flags; | 
 |  | 
 | 		flags = dev_get_flags(dev); | 
 | 		if (!(flags & (IFF_RUNNING | IFF_LOWER_UP))) | 
 | 			nh->nh_flags |= RTNH_F_LINKDOWN; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 |  | 
 | errout: | 
 | 	return err; | 
 | } | 
 |  | 
 | static int mpls_nh_build_from_cfg(struct mpls_route_config *cfg, | 
 | 				  struct mpls_route *rt) | 
 | { | 
 | 	struct net *net = cfg->rc_nlinfo.nl_net; | 
 | 	struct mpls_nh *nh = rt->rt_nh; | 
 | 	int err; | 
 | 	int i; | 
 |  | 
 | 	if (!nh) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	err = -EINVAL; | 
 | 	/* Ensure only a supported number of labels are present */ | 
 | 	if (cfg->rc_output_labels > MAX_NEW_LABELS) | 
 | 		goto errout; | 
 |  | 
 | 	nh->nh_labels = cfg->rc_output_labels; | 
 | 	for (i = 0; i < nh->nh_labels; i++) | 
 | 		nh->nh_label[i] = cfg->rc_output_label[i]; | 
 |  | 
 | 	nh->nh_via_table = cfg->rc_via_table; | 
 | 	memcpy(__mpls_nh_via(rt, nh), cfg->rc_via, cfg->rc_via_alen); | 
 | 	nh->nh_via_alen = cfg->rc_via_alen; | 
 |  | 
 | 	err = mpls_nh_assign_dev(net, rt, nh, cfg->rc_ifindex); | 
 | 	if (err) | 
 | 		goto errout; | 
 |  | 
 | 	if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) | 
 | 		rt->rt_nhn_alive--; | 
 |  | 
 | 	return 0; | 
 |  | 
 | errout: | 
 | 	return err; | 
 | } | 
 |  | 
 | static int mpls_nh_build(struct net *net, struct mpls_route *rt, | 
 | 			 struct mpls_nh *nh, int oif, struct nlattr *via, | 
 | 			 struct nlattr *newdst) | 
 | { | 
 | 	int err = -ENOMEM; | 
 |  | 
 | 	if (!nh) | 
 | 		goto errout; | 
 |  | 
 | 	if (newdst) { | 
 | 		err = nla_get_labels(newdst, MAX_NEW_LABELS, | 
 | 				     &nh->nh_labels, nh->nh_label); | 
 | 		if (err) | 
 | 			goto errout; | 
 | 	} | 
 |  | 
 | 	if (via) { | 
 | 		err = nla_get_via(via, &nh->nh_via_alen, &nh->nh_via_table, | 
 | 				  __mpls_nh_via(rt, nh)); | 
 | 		if (err) | 
 | 			goto errout; | 
 | 	} else { | 
 | 		nh->nh_via_table = MPLS_NEIGH_TABLE_UNSPEC; | 
 | 	} | 
 |  | 
 | 	err = mpls_nh_assign_dev(net, rt, nh, oif); | 
 | 	if (err) | 
 | 		goto errout; | 
 |  | 
 | 	return 0; | 
 |  | 
 | errout: | 
 | 	return err; | 
 | } | 
 |  | 
 | static int mpls_count_nexthops(struct rtnexthop *rtnh, int len, | 
 | 			       u8 cfg_via_alen, u8 *max_via_alen) | 
 | { | 
 | 	int nhs = 0; | 
 | 	int remaining = len; | 
 |  | 
 | 	if (!rtnh) { | 
 | 		*max_via_alen = cfg_via_alen; | 
 | 		return 1; | 
 | 	} | 
 |  | 
 | 	*max_via_alen = 0; | 
 |  | 
 | 	while (rtnh_ok(rtnh, remaining)) { | 
 | 		struct nlattr *nla, *attrs = rtnh_attrs(rtnh); | 
 | 		int attrlen; | 
 |  | 
 | 		attrlen = rtnh_attrlen(rtnh); | 
 | 		nla = nla_find(attrs, attrlen, RTA_VIA); | 
 | 		if (nla && nla_len(nla) >= | 
 | 		    offsetof(struct rtvia, rtvia_addr)) { | 
 | 			int via_alen = nla_len(nla) - | 
 | 				offsetof(struct rtvia, rtvia_addr); | 
 |  | 
 | 			if (via_alen <= MAX_VIA_ALEN) | 
 | 				*max_via_alen = max_t(u16, *max_via_alen, | 
 | 						      via_alen); | 
 | 		} | 
 |  | 
 | 		nhs++; | 
 | 		rtnh = rtnh_next(rtnh, &remaining); | 
 | 	} | 
 |  | 
 | 	/* leftover implies invalid nexthop configuration, discard it */ | 
 | 	return remaining > 0 ? 0 : nhs; | 
 | } | 
 |  | 
 | static int mpls_nh_build_multi(struct mpls_route_config *cfg, | 
 | 			       struct mpls_route *rt) | 
 | { | 
 | 	struct rtnexthop *rtnh = cfg->rc_mp; | 
 | 	struct nlattr *nla_via, *nla_newdst; | 
 | 	int remaining = cfg->rc_mp_len; | 
 | 	int nhs = 0; | 
 | 	int err = 0; | 
 |  | 
 | 	change_nexthops(rt) { | 
 | 		int attrlen; | 
 |  | 
 | 		nla_via = NULL; | 
 | 		nla_newdst = NULL; | 
 |  | 
 | 		err = -EINVAL; | 
 | 		if (!rtnh_ok(rtnh, remaining)) | 
 | 			goto errout; | 
 |  | 
 | 		/* neither weighted multipath nor any flags | 
 | 		 * are supported | 
 | 		 */ | 
 | 		if (rtnh->rtnh_hops || rtnh->rtnh_flags) | 
 | 			goto errout; | 
 |  | 
 | 		attrlen = rtnh_attrlen(rtnh); | 
 | 		if (attrlen > 0) { | 
 | 			struct nlattr *attrs = rtnh_attrs(rtnh); | 
 |  | 
 | 			nla_via = nla_find(attrs, attrlen, RTA_VIA); | 
 | 			nla_newdst = nla_find(attrs, attrlen, RTA_NEWDST); | 
 | 		} | 
 |  | 
 | 		err = mpls_nh_build(cfg->rc_nlinfo.nl_net, rt, nh, | 
 | 				    rtnh->rtnh_ifindex, nla_via, nla_newdst); | 
 | 		if (err) | 
 | 			goto errout; | 
 |  | 
 | 		if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN)) | 
 | 			rt->rt_nhn_alive--; | 
 |  | 
 | 		rtnh = rtnh_next(rtnh, &remaining); | 
 | 		nhs++; | 
 | 	} endfor_nexthops(rt); | 
 |  | 
 | 	rt->rt_nhn = nhs; | 
 |  | 
 | 	return 0; | 
 |  | 
 | errout: | 
 | 	return err; | 
 | } | 
 |  | 
 | static bool mpls_label_ok(struct net *net, unsigned int *index) | 
 | { | 
 | 	bool is_ok = true; | 
 |  | 
 | 	/* Reserved labels may not be set */ | 
 | 	if (*index < MPLS_LABEL_FIRST_UNRESERVED) | 
 | 		is_ok = false; | 
 |  | 
 | 	/* The full 20 bit range may not be supported. */ | 
 | 	if (is_ok && *index >= net->mpls.platform_labels) | 
 | 		is_ok = false; | 
 |  | 
 | 	*index = array_index_nospec(*index, net->mpls.platform_labels); | 
 | 	return is_ok; | 
 | } | 
 |  | 
 | static int mpls_route_add(struct mpls_route_config *cfg) | 
 | { | 
 | 	struct mpls_route __rcu **platform_label; | 
 | 	struct net *net = cfg->rc_nlinfo.nl_net; | 
 | 	struct mpls_route *rt, *old; | 
 | 	int err = -EINVAL; | 
 | 	u8 max_via_alen; | 
 | 	unsigned index; | 
 | 	int nhs; | 
 |  | 
 | 	index = cfg->rc_label; | 
 |  | 
 | 	/* If a label was not specified during insert pick one */ | 
 | 	if ((index == LABEL_NOT_SPECIFIED) && | 
 | 	    (cfg->rc_nlflags & NLM_F_CREATE)) { | 
 | 		index = find_free_label(net); | 
 | 	} | 
 |  | 
 | 	if (!mpls_label_ok(net, &index)) | 
 | 		goto errout; | 
 |  | 
 | 	/* Append makes no sense with mpls */ | 
 | 	err = -EOPNOTSUPP; | 
 | 	if (cfg->rc_nlflags & NLM_F_APPEND) | 
 | 		goto errout; | 
 |  | 
 | 	err = -EEXIST; | 
 | 	platform_label = rtnl_dereference(net->mpls.platform_label); | 
 | 	old = rtnl_dereference(platform_label[index]); | 
 | 	if ((cfg->rc_nlflags & NLM_F_EXCL) && old) | 
 | 		goto errout; | 
 |  | 
 | 	err = -EEXIST; | 
 | 	if (!(cfg->rc_nlflags & NLM_F_REPLACE) && old) | 
 | 		goto errout; | 
 |  | 
 | 	err = -ENOENT; | 
 | 	if (!(cfg->rc_nlflags & NLM_F_CREATE) && !old) | 
 | 		goto errout; | 
 |  | 
 | 	err = -EINVAL; | 
 | 	nhs = mpls_count_nexthops(cfg->rc_mp, cfg->rc_mp_len, | 
 | 				  cfg->rc_via_alen, &max_via_alen); | 
 | 	if (nhs == 0) | 
 | 		goto errout; | 
 |  | 
 | 	err = -ENOMEM; | 
 | 	rt = mpls_rt_alloc(nhs, max_via_alen); | 
 | 	if (!rt) | 
 | 		goto errout; | 
 |  | 
 | 	rt->rt_protocol = cfg->rc_protocol; | 
 | 	rt->rt_payload_type = cfg->rc_payload_type; | 
 |  | 
 | 	if (cfg->rc_mp) | 
 | 		err = mpls_nh_build_multi(cfg, rt); | 
 | 	else | 
 | 		err = mpls_nh_build_from_cfg(cfg, rt); | 
 | 	if (err) | 
 | 		goto freert; | 
 |  | 
 | 	mpls_route_update(net, index, rt, &cfg->rc_nlinfo); | 
 |  | 
 | 	return 0; | 
 |  | 
 | freert: | 
 | 	mpls_rt_free(rt); | 
 | errout: | 
 | 	return err; | 
 | } | 
 |  | 
 | static int mpls_route_del(struct mpls_route_config *cfg) | 
 | { | 
 | 	struct net *net = cfg->rc_nlinfo.nl_net; | 
 | 	unsigned index; | 
 | 	int err = -EINVAL; | 
 |  | 
 | 	index = cfg->rc_label; | 
 |  | 
 | 	if (!mpls_label_ok(net, &index)) | 
 | 		goto errout; | 
 |  | 
 | 	mpls_route_update(net, index, NULL, &cfg->rc_nlinfo); | 
 |  | 
 | 	err = 0; | 
 | errout: | 
 | 	return err; | 
 | } | 
 |  | 
 | #define MPLS_PERDEV_SYSCTL_OFFSET(field)	\ | 
 | 	(&((struct mpls_dev *)0)->field) | 
 |  | 
 | static const struct ctl_table mpls_dev_table[] = { | 
 | 	{ | 
 | 		.procname	= "input", | 
 | 		.maxlen		= sizeof(int), | 
 | 		.mode		= 0644, | 
 | 		.proc_handler	= proc_dointvec, | 
 | 		.data		= MPLS_PERDEV_SYSCTL_OFFSET(input_enabled), | 
 | 	}, | 
 | 	{ } | 
 | }; | 
 |  | 
 | static int mpls_dev_sysctl_register(struct net_device *dev, | 
 | 				    struct mpls_dev *mdev) | 
 | { | 
 | 	char path[sizeof("net/mpls/conf/") + IFNAMSIZ]; | 
 | 	struct ctl_table *table; | 
 | 	int i; | 
 |  | 
 | 	table = kmemdup(&mpls_dev_table, sizeof(mpls_dev_table), GFP_KERNEL); | 
 | 	if (!table) | 
 | 		goto out; | 
 |  | 
 | 	/* Table data contains only offsets relative to the base of | 
 | 	 * the mdev at this point, so make them absolute. | 
 | 	 */ | 
 | 	for (i = 0; i < ARRAY_SIZE(mpls_dev_table); i++) | 
 | 		table[i].data = (char *)mdev + (uintptr_t)table[i].data; | 
 |  | 
 | 	snprintf(path, sizeof(path), "net/mpls/conf/%s", dev->name); | 
 |  | 
 | 	mdev->sysctl = register_net_sysctl(dev_net(dev), path, table); | 
 | 	if (!mdev->sysctl) | 
 | 		goto free; | 
 |  | 
 | 	return 0; | 
 |  | 
 | free: | 
 | 	kfree(table); | 
 | out: | 
 | 	return -ENOBUFS; | 
 | } | 
 |  | 
 | static void mpls_dev_sysctl_unregister(struct mpls_dev *mdev) | 
 | { | 
 | 	struct ctl_table *table; | 
 |  | 
 | 	table = mdev->sysctl->ctl_table_arg; | 
 | 	unregister_net_sysctl_table(mdev->sysctl); | 
 | 	kfree(table); | 
 | } | 
 |  | 
 | static struct mpls_dev *mpls_add_dev(struct net_device *dev) | 
 | { | 
 | 	struct mpls_dev *mdev; | 
 | 	int err = -ENOMEM; | 
 |  | 
 | 	ASSERT_RTNL(); | 
 |  | 
 | 	mdev = kzalloc(sizeof(*mdev), GFP_KERNEL); | 
 | 	if (!mdev) | 
 | 		return ERR_PTR(err); | 
 |  | 
 | 	err = mpls_dev_sysctl_register(dev, mdev); | 
 | 	if (err) | 
 | 		goto free; | 
 |  | 
 | 	rcu_assign_pointer(dev->mpls_ptr, mdev); | 
 |  | 
 | 	return mdev; | 
 |  | 
 | free: | 
 | 	kfree(mdev); | 
 | 	return ERR_PTR(err); | 
 | } | 
 |  | 
 | static void mpls_ifdown(struct net_device *dev, int event) | 
 | { | 
 | 	struct mpls_route __rcu **platform_label; | 
 | 	struct net *net = dev_net(dev); | 
 | 	unsigned int nh_flags = RTNH_F_DEAD | RTNH_F_LINKDOWN; | 
 | 	unsigned int alive; | 
 | 	unsigned index; | 
 |  | 
 | 	platform_label = rtnl_dereference(net->mpls.platform_label); | 
 | 	for (index = 0; index < net->mpls.platform_labels; index++) { | 
 | 		struct mpls_route *rt = rtnl_dereference(platform_label[index]); | 
 |  | 
 | 		if (!rt) | 
 | 			continue; | 
 |  | 
 | 		alive = 0; | 
 | 		change_nexthops(rt) { | 
 | 			if (rtnl_dereference(nh->nh_dev) != dev) | 
 | 				goto next; | 
 |  | 
 | 			switch (event) { | 
 | 			case NETDEV_DOWN: | 
 | 			case NETDEV_UNREGISTER: | 
 | 				nh->nh_flags |= RTNH_F_DEAD; | 
 | 				/* fall through */ | 
 | 			case NETDEV_CHANGE: | 
 | 				nh->nh_flags |= RTNH_F_LINKDOWN; | 
 | 				break; | 
 | 			} | 
 | 			if (event == NETDEV_UNREGISTER) | 
 | 				RCU_INIT_POINTER(nh->nh_dev, NULL); | 
 | next: | 
 | 			if (!(nh->nh_flags & nh_flags)) | 
 | 				alive++; | 
 | 		} endfor_nexthops(rt); | 
 |  | 
 | 		WRITE_ONCE(rt->rt_nhn_alive, alive); | 
 | 	} | 
 | } | 
 |  | 
 | static void mpls_ifup(struct net_device *dev, unsigned int nh_flags) | 
 | { | 
 | 	struct mpls_route __rcu **platform_label; | 
 | 	struct net *net = dev_net(dev); | 
 | 	unsigned index; | 
 | 	int alive; | 
 |  | 
 | 	platform_label = rtnl_dereference(net->mpls.platform_label); | 
 | 	for (index = 0; index < net->mpls.platform_labels; index++) { | 
 | 		struct mpls_route *rt = rtnl_dereference(platform_label[index]); | 
 |  | 
 | 		if (!rt) | 
 | 			continue; | 
 |  | 
 | 		alive = 0; | 
 | 		change_nexthops(rt) { | 
 | 			struct net_device *nh_dev = | 
 | 				rtnl_dereference(nh->nh_dev); | 
 |  | 
 | 			if (!(nh->nh_flags & nh_flags)) { | 
 | 				alive++; | 
 | 				continue; | 
 | 			} | 
 | 			if (nh_dev != dev) | 
 | 				continue; | 
 | 			alive++; | 
 | 			nh->nh_flags &= ~nh_flags; | 
 | 		} endfor_nexthops(rt); | 
 |  | 
 | 		ACCESS_ONCE(rt->rt_nhn_alive) = alive; | 
 | 	} | 
 | } | 
 |  | 
 | static int mpls_dev_notify(struct notifier_block *this, unsigned long event, | 
 | 			   void *ptr) | 
 | { | 
 | 	struct net_device *dev = netdev_notifier_info_to_dev(ptr); | 
 | 	struct mpls_dev *mdev; | 
 | 	unsigned int flags; | 
 |  | 
 | 	if (event == NETDEV_REGISTER) { | 
 | 		/* For now just support Ethernet, IPGRE, SIT and IPIP devices */ | 
 | 		if (dev->type == ARPHRD_ETHER || | 
 | 		    dev->type == ARPHRD_LOOPBACK || | 
 | 		    dev->type == ARPHRD_IPGRE || | 
 | 		    dev->type == ARPHRD_SIT || | 
 | 		    dev->type == ARPHRD_TUNNEL) { | 
 | 			mdev = mpls_add_dev(dev); | 
 | 			if (IS_ERR(mdev)) | 
 | 				return notifier_from_errno(PTR_ERR(mdev)); | 
 | 		} | 
 | 		return NOTIFY_OK; | 
 | 	} | 
 |  | 
 | 	mdev = mpls_dev_get(dev); | 
 | 	if (!mdev) | 
 | 		return NOTIFY_OK; | 
 |  | 
 | 	switch (event) { | 
 | 	case NETDEV_DOWN: | 
 | 		mpls_ifdown(dev, event); | 
 | 		break; | 
 | 	case NETDEV_UP: | 
 | 		flags = dev_get_flags(dev); | 
 | 		if (flags & (IFF_RUNNING | IFF_LOWER_UP)) | 
 | 			mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN); | 
 | 		else | 
 | 			mpls_ifup(dev, RTNH_F_DEAD); | 
 | 		break; | 
 | 	case NETDEV_CHANGE: | 
 | 		flags = dev_get_flags(dev); | 
 | 		if (flags & (IFF_RUNNING | IFF_LOWER_UP)) | 
 | 			mpls_ifup(dev, RTNH_F_DEAD | RTNH_F_LINKDOWN); | 
 | 		else | 
 | 			mpls_ifdown(dev, event); | 
 | 		break; | 
 | 	case NETDEV_UNREGISTER: | 
 | 		mpls_ifdown(dev, event); | 
 | 		mdev = mpls_dev_get(dev); | 
 | 		if (mdev) { | 
 | 			mpls_dev_sysctl_unregister(mdev); | 
 | 			RCU_INIT_POINTER(dev->mpls_ptr, NULL); | 
 | 			kfree_rcu(mdev, rcu); | 
 | 		} | 
 | 		break; | 
 | 	case NETDEV_CHANGENAME: | 
 | 		mdev = mpls_dev_get(dev); | 
 | 		if (mdev) { | 
 | 			int err; | 
 |  | 
 | 			mpls_dev_sysctl_unregister(mdev); | 
 | 			err = mpls_dev_sysctl_register(dev, mdev); | 
 | 			if (err) | 
 | 				return notifier_from_errno(err); | 
 | 		} | 
 | 		break; | 
 | 	} | 
 | 	return NOTIFY_OK; | 
 | } | 
 |  | 
 | static struct notifier_block mpls_dev_notifier = { | 
 | 	.notifier_call = mpls_dev_notify, | 
 | }; | 
 |  | 
 | static int nla_put_via(struct sk_buff *skb, | 
 | 		       u8 table, const void *addr, int alen) | 
 | { | 
 | 	static const int table_to_family[NEIGH_NR_TABLES + 1] = { | 
 | 		AF_INET, AF_INET6, AF_DECnet, AF_PACKET, | 
 | 	}; | 
 | 	struct nlattr *nla; | 
 | 	struct rtvia *via; | 
 | 	int family = AF_UNSPEC; | 
 |  | 
 | 	nla = nla_reserve(skb, RTA_VIA, alen + 2); | 
 | 	if (!nla) | 
 | 		return -EMSGSIZE; | 
 |  | 
 | 	if (table <= NEIGH_NR_TABLES) | 
 | 		family = table_to_family[table]; | 
 |  | 
 | 	via = nla_data(nla); | 
 | 	via->rtvia_family = family; | 
 | 	memcpy(via->rtvia_addr, addr, alen); | 
 | 	return 0; | 
 | } | 
 |  | 
 | int nla_put_labels(struct sk_buff *skb, int attrtype, | 
 | 		   u8 labels, const u32 label[]) | 
 | { | 
 | 	struct nlattr *nla; | 
 | 	struct mpls_shim_hdr *nla_label; | 
 | 	bool bos; | 
 | 	int i; | 
 | 	nla = nla_reserve(skb, attrtype, labels*4); | 
 | 	if (!nla) | 
 | 		return -EMSGSIZE; | 
 |  | 
 | 	nla_label = nla_data(nla); | 
 | 	bos = true; | 
 | 	for (i = labels - 1; i >= 0; i--) { | 
 | 		nla_label[i] = mpls_entry_encode(label[i], 0, 0, bos); | 
 | 		bos = false; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 | EXPORT_SYMBOL_GPL(nla_put_labels); | 
 |  | 
 | int nla_get_labels(const struct nlattr *nla, | 
 | 		   u32 max_labels, u8 *labels, u32 label[]) | 
 | { | 
 | 	unsigned len = nla_len(nla); | 
 | 	unsigned nla_labels; | 
 | 	struct mpls_shim_hdr *nla_label; | 
 | 	bool bos; | 
 | 	int i; | 
 |  | 
 | 	/* len needs to be an even multiple of 4 (the label size) */ | 
 | 	if (len & 3) | 
 | 		return -EINVAL; | 
 |  | 
 | 	/* Limit the number of new labels allowed */ | 
 | 	nla_labels = len/4; | 
 | 	if (nla_labels > max_labels) | 
 | 		return -EINVAL; | 
 |  | 
 | 	nla_label = nla_data(nla); | 
 | 	bos = true; | 
 | 	for (i = nla_labels - 1; i >= 0; i--, bos = false) { | 
 | 		struct mpls_entry_decoded dec; | 
 | 		dec = mpls_entry_decode(nla_label + i); | 
 |  | 
 | 		/* Ensure the bottom of stack flag is properly set | 
 | 		 * and ttl and tc are both clear. | 
 | 		 */ | 
 | 		if ((dec.bos != bos) || dec.ttl || dec.tc) | 
 | 			return -EINVAL; | 
 |  | 
 | 		switch (dec.label) { | 
 | 		case MPLS_LABEL_IMPLNULL: | 
 | 			/* RFC3032: This is a label that an LSR may | 
 | 			 * assign and distribute, but which never | 
 | 			 * actually appears in the encapsulation. | 
 | 			 */ | 
 | 			return -EINVAL; | 
 | 		} | 
 |  | 
 | 		label[i] = dec.label; | 
 | 	} | 
 | 	*labels = nla_labels; | 
 | 	return 0; | 
 | } | 
 | EXPORT_SYMBOL_GPL(nla_get_labels); | 
 |  | 
 | int nla_get_via(const struct nlattr *nla, u8 *via_alen, | 
 | 		u8 *via_table, u8 via_addr[]) | 
 | { | 
 | 	struct rtvia *via = nla_data(nla); | 
 | 	int err = -EINVAL; | 
 | 	int alen; | 
 |  | 
 | 	if (nla_len(nla) < offsetof(struct rtvia, rtvia_addr)) | 
 | 		goto errout; | 
 | 	alen = nla_len(nla) - | 
 | 			offsetof(struct rtvia, rtvia_addr); | 
 | 	if (alen > MAX_VIA_ALEN) | 
 | 		goto errout; | 
 |  | 
 | 	/* Validate the address family */ | 
 | 	switch (via->rtvia_family) { | 
 | 	case AF_PACKET: | 
 | 		*via_table = NEIGH_LINK_TABLE; | 
 | 		break; | 
 | 	case AF_INET: | 
 | 		*via_table = NEIGH_ARP_TABLE; | 
 | 		if (alen != 4) | 
 | 			goto errout; | 
 | 		break; | 
 | 	case AF_INET6: | 
 | 		*via_table = NEIGH_ND_TABLE; | 
 | 		if (alen != 16) | 
 | 			goto errout; | 
 | 		break; | 
 | 	default: | 
 | 		/* Unsupported address family */ | 
 | 		goto errout; | 
 | 	} | 
 |  | 
 | 	memcpy(via_addr, via->rtvia_addr, alen); | 
 | 	*via_alen = alen; | 
 | 	err = 0; | 
 |  | 
 | errout: | 
 | 	return err; | 
 | } | 
 |  | 
 | static int rtm_to_route_config(struct sk_buff *skb,  struct nlmsghdr *nlh, | 
 | 			       struct mpls_route_config *cfg) | 
 | { | 
 | 	struct rtmsg *rtm; | 
 | 	struct nlattr *tb[RTA_MAX+1]; | 
 | 	int index; | 
 | 	int err; | 
 |  | 
 | 	err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_mpls_policy); | 
 | 	if (err < 0) | 
 | 		goto errout; | 
 |  | 
 | 	err = -EINVAL; | 
 | 	rtm = nlmsg_data(nlh); | 
 | 	memset(cfg, 0, sizeof(*cfg)); | 
 |  | 
 | 	if (rtm->rtm_family != AF_MPLS) | 
 | 		goto errout; | 
 | 	if (rtm->rtm_dst_len != 20) | 
 | 		goto errout; | 
 | 	if (rtm->rtm_src_len != 0) | 
 | 		goto errout; | 
 | 	if (rtm->rtm_tos != 0) | 
 | 		goto errout; | 
 | 	if (rtm->rtm_table != RT_TABLE_MAIN) | 
 | 		goto errout; | 
 | 	/* Any value is acceptable for rtm_protocol */ | 
 |  | 
 | 	/* As mpls uses destination specific addresses | 
 | 	 * (or source specific address in the case of multicast) | 
 | 	 * all addresses have universal scope. | 
 | 	 */ | 
 | 	if (rtm->rtm_scope != RT_SCOPE_UNIVERSE) | 
 | 		goto errout; | 
 | 	if (rtm->rtm_type != RTN_UNICAST) | 
 | 		goto errout; | 
 | 	if (rtm->rtm_flags != 0) | 
 | 		goto errout; | 
 |  | 
 | 	cfg->rc_label		= LABEL_NOT_SPECIFIED; | 
 | 	cfg->rc_protocol	= rtm->rtm_protocol; | 
 | 	cfg->rc_via_table	= MPLS_NEIGH_TABLE_UNSPEC; | 
 | 	cfg->rc_nlflags		= nlh->nlmsg_flags; | 
 | 	cfg->rc_nlinfo.portid	= NETLINK_CB(skb).portid; | 
 | 	cfg->rc_nlinfo.nlh	= nlh; | 
 | 	cfg->rc_nlinfo.nl_net	= sock_net(skb->sk); | 
 |  | 
 | 	for (index = 0; index <= RTA_MAX; index++) { | 
 | 		struct nlattr *nla = tb[index]; | 
 | 		if (!nla) | 
 | 			continue; | 
 |  | 
 | 		switch (index) { | 
 | 		case RTA_OIF: | 
 | 			cfg->rc_ifindex = nla_get_u32(nla); | 
 | 			break; | 
 | 		case RTA_NEWDST: | 
 | 			if (nla_get_labels(nla, MAX_NEW_LABELS, | 
 | 					   &cfg->rc_output_labels, | 
 | 					   cfg->rc_output_label)) | 
 | 				goto errout; | 
 | 			break; | 
 | 		case RTA_DST: | 
 | 		{ | 
 | 			u8 label_count; | 
 | 			if (nla_get_labels(nla, 1, &label_count, | 
 | 					   &cfg->rc_label)) | 
 | 				goto errout; | 
 |  | 
 | 			if (!mpls_label_ok(cfg->rc_nlinfo.nl_net, | 
 | 					   &cfg->rc_label)) | 
 | 				goto errout; | 
 | 			break; | 
 | 		} | 
 | 		case RTA_VIA: | 
 | 		{ | 
 | 			if (nla_get_via(nla, &cfg->rc_via_alen, | 
 | 					&cfg->rc_via_table, cfg->rc_via)) | 
 | 				goto errout; | 
 | 			break; | 
 | 		} | 
 | 		case RTA_MULTIPATH: | 
 | 		{ | 
 | 			cfg->rc_mp = nla_data(nla); | 
 | 			cfg->rc_mp_len = nla_len(nla); | 
 | 			break; | 
 | 		} | 
 | 		default: | 
 | 			/* Unsupported attribute */ | 
 | 			goto errout; | 
 | 		} | 
 | 	} | 
 |  | 
 | 	err = 0; | 
 | errout: | 
 | 	return err; | 
 | } | 
 |  | 
 | static int mpls_rtm_delroute(struct sk_buff *skb, struct nlmsghdr *nlh) | 
 | { | 
 | 	struct mpls_route_config cfg; | 
 | 	int err; | 
 |  | 
 | 	err = rtm_to_route_config(skb, nlh, &cfg); | 
 | 	if (err < 0) | 
 | 		return err; | 
 |  | 
 | 	return mpls_route_del(&cfg); | 
 | } | 
 |  | 
 |  | 
 | static int mpls_rtm_newroute(struct sk_buff *skb, struct nlmsghdr *nlh) | 
 | { | 
 | 	struct mpls_route_config cfg; | 
 | 	int err; | 
 |  | 
 | 	err = rtm_to_route_config(skb, nlh, &cfg); | 
 | 	if (err < 0) | 
 | 		return err; | 
 |  | 
 | 	return mpls_route_add(&cfg); | 
 | } | 
 |  | 
 | static int mpls_dump_route(struct sk_buff *skb, u32 portid, u32 seq, int event, | 
 | 			   u32 label, struct mpls_route *rt, int flags) | 
 | { | 
 | 	struct net_device *dev; | 
 | 	struct nlmsghdr *nlh; | 
 | 	struct rtmsg *rtm; | 
 |  | 
 | 	nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), flags); | 
 | 	if (nlh == NULL) | 
 | 		return -EMSGSIZE; | 
 |  | 
 | 	rtm = nlmsg_data(nlh); | 
 | 	rtm->rtm_family = AF_MPLS; | 
 | 	rtm->rtm_dst_len = 20; | 
 | 	rtm->rtm_src_len = 0; | 
 | 	rtm->rtm_tos = 0; | 
 | 	rtm->rtm_table = RT_TABLE_MAIN; | 
 | 	rtm->rtm_protocol = rt->rt_protocol; | 
 | 	rtm->rtm_scope = RT_SCOPE_UNIVERSE; | 
 | 	rtm->rtm_type = RTN_UNICAST; | 
 | 	rtm->rtm_flags = 0; | 
 |  | 
 | 	if (nla_put_labels(skb, RTA_DST, 1, &label)) | 
 | 		goto nla_put_failure; | 
 | 	if (rt->rt_nhn == 1) { | 
 | 		const struct mpls_nh *nh = rt->rt_nh; | 
 |  | 
 | 		if (nh->nh_labels && | 
 | 		    nla_put_labels(skb, RTA_NEWDST, nh->nh_labels, | 
 | 				   nh->nh_label)) | 
 | 			goto nla_put_failure; | 
 | 		if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && | 
 | 		    nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh), | 
 | 				nh->nh_via_alen)) | 
 | 			goto nla_put_failure; | 
 | 		dev = rtnl_dereference(nh->nh_dev); | 
 | 		if (dev && nla_put_u32(skb, RTA_OIF, dev->ifindex)) | 
 | 			goto nla_put_failure; | 
 | 		if (nh->nh_flags & RTNH_F_LINKDOWN) | 
 | 			rtm->rtm_flags |= RTNH_F_LINKDOWN; | 
 | 		if (nh->nh_flags & RTNH_F_DEAD) | 
 | 			rtm->rtm_flags |= RTNH_F_DEAD; | 
 | 	} else { | 
 | 		struct rtnexthop *rtnh; | 
 | 		struct nlattr *mp; | 
 | 		int dead = 0; | 
 | 		int linkdown = 0; | 
 |  | 
 | 		mp = nla_nest_start(skb, RTA_MULTIPATH); | 
 | 		if (!mp) | 
 | 			goto nla_put_failure; | 
 |  | 
 | 		for_nexthops(rt) { | 
 | 			rtnh = nla_reserve_nohdr(skb, sizeof(*rtnh)); | 
 | 			if (!rtnh) | 
 | 				goto nla_put_failure; | 
 |  | 
 | 			dev = rtnl_dereference(nh->nh_dev); | 
 | 			if (dev) | 
 | 				rtnh->rtnh_ifindex = dev->ifindex; | 
 | 			if (nh->nh_flags & RTNH_F_LINKDOWN) { | 
 | 				rtnh->rtnh_flags |= RTNH_F_LINKDOWN; | 
 | 				linkdown++; | 
 | 			} | 
 | 			if (nh->nh_flags & RTNH_F_DEAD) { | 
 | 				rtnh->rtnh_flags |= RTNH_F_DEAD; | 
 | 				dead++; | 
 | 			} | 
 |  | 
 | 			if (nh->nh_labels && nla_put_labels(skb, RTA_NEWDST, | 
 | 							    nh->nh_labels, | 
 | 							    nh->nh_label)) | 
 | 				goto nla_put_failure; | 
 | 			if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC && | 
 | 			    nla_put_via(skb, nh->nh_via_table, | 
 | 					mpls_nh_via(rt, nh), | 
 | 					nh->nh_via_alen)) | 
 | 				goto nla_put_failure; | 
 |  | 
 | 			/* length of rtnetlink header + attributes */ | 
 | 			rtnh->rtnh_len = nlmsg_get_pos(skb) - (void *)rtnh; | 
 | 		} endfor_nexthops(rt); | 
 |  | 
 | 		if (linkdown == rt->rt_nhn) | 
 | 			rtm->rtm_flags |= RTNH_F_LINKDOWN; | 
 | 		if (dead == rt->rt_nhn) | 
 | 			rtm->rtm_flags |= RTNH_F_DEAD; | 
 |  | 
 | 		nla_nest_end(skb, mp); | 
 | 	} | 
 |  | 
 | 	nlmsg_end(skb, nlh); | 
 | 	return 0; | 
 |  | 
 | nla_put_failure: | 
 | 	nlmsg_cancel(skb, nlh); | 
 | 	return -EMSGSIZE; | 
 | } | 
 |  | 
 | static int mpls_dump_routes(struct sk_buff *skb, struct netlink_callback *cb) | 
 | { | 
 | 	struct net *net = sock_net(skb->sk); | 
 | 	struct mpls_route __rcu **platform_label; | 
 | 	size_t platform_labels; | 
 | 	unsigned int index; | 
 |  | 
 | 	ASSERT_RTNL(); | 
 |  | 
 | 	index = cb->args[0]; | 
 | 	if (index < MPLS_LABEL_FIRST_UNRESERVED) | 
 | 		index = MPLS_LABEL_FIRST_UNRESERVED; | 
 |  | 
 | 	platform_label = rtnl_dereference(net->mpls.platform_label); | 
 | 	platform_labels = net->mpls.platform_labels; | 
 | 	for (; index < platform_labels; index++) { | 
 | 		struct mpls_route *rt; | 
 | 		rt = rtnl_dereference(platform_label[index]); | 
 | 		if (!rt) | 
 | 			continue; | 
 |  | 
 | 		if (mpls_dump_route(skb, NETLINK_CB(cb->skb).portid, | 
 | 				    cb->nlh->nlmsg_seq, RTM_NEWROUTE, | 
 | 				    index, rt, NLM_F_MULTI) < 0) | 
 | 			break; | 
 | 	} | 
 | 	cb->args[0] = index; | 
 |  | 
 | 	return skb->len; | 
 | } | 
 |  | 
 | static inline size_t lfib_nlmsg_size(struct mpls_route *rt) | 
 | { | 
 | 	size_t payload = | 
 | 		NLMSG_ALIGN(sizeof(struct rtmsg)) | 
 | 		+ nla_total_size(4);			/* RTA_DST */ | 
 |  | 
 | 	if (rt->rt_nhn == 1) { | 
 | 		struct mpls_nh *nh = rt->rt_nh; | 
 |  | 
 | 		if (nh->nh_dev) | 
 | 			payload += nla_total_size(4); /* RTA_OIF */ | 
 | 		if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) /* RTA_VIA */ | 
 | 			payload += nla_total_size(2 + nh->nh_via_alen); | 
 | 		if (nh->nh_labels) /* RTA_NEWDST */ | 
 | 			payload += nla_total_size(nh->nh_labels * 4); | 
 | 	} else { | 
 | 		/* each nexthop is packed in an attribute */ | 
 | 		size_t nhsize = 0; | 
 |  | 
 | 		for_nexthops(rt) { | 
 | 			nhsize += nla_total_size(sizeof(struct rtnexthop)); | 
 | 			/* RTA_VIA */ | 
 | 			if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) | 
 | 				nhsize += nla_total_size(2 + nh->nh_via_alen); | 
 | 			if (nh->nh_labels) | 
 | 				nhsize += nla_total_size(nh->nh_labels * 4); | 
 | 		} endfor_nexthops(rt); | 
 | 		/* nested attribute */ | 
 | 		payload += nla_total_size(nhsize); | 
 | 	} | 
 |  | 
 | 	return payload; | 
 | } | 
 |  | 
 | static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt, | 
 | 		       struct nlmsghdr *nlh, struct net *net, u32 portid, | 
 | 		       unsigned int nlm_flags) | 
 | { | 
 | 	struct sk_buff *skb; | 
 | 	u32 seq = nlh ? nlh->nlmsg_seq : 0; | 
 | 	int err = -ENOBUFS; | 
 |  | 
 | 	skb = nlmsg_new(lfib_nlmsg_size(rt), GFP_KERNEL); | 
 | 	if (skb == NULL) | 
 | 		goto errout; | 
 |  | 
 | 	err = mpls_dump_route(skb, portid, seq, event, label, rt, nlm_flags); | 
 | 	if (err < 0) { | 
 | 		/* -EMSGSIZE implies BUG in lfib_nlmsg_size */ | 
 | 		WARN_ON(err == -EMSGSIZE); | 
 | 		kfree_skb(skb); | 
 | 		goto errout; | 
 | 	} | 
 | 	rtnl_notify(skb, net, portid, RTNLGRP_MPLS_ROUTE, nlh, GFP_KERNEL); | 
 |  | 
 | 	return; | 
 | errout: | 
 | 	if (err < 0) | 
 | 		rtnl_set_sk_err(net, RTNLGRP_MPLS_ROUTE, err); | 
 | } | 
 |  | 
 | static int resize_platform_label_table(struct net *net, size_t limit) | 
 | { | 
 | 	size_t size = sizeof(struct mpls_route *) * limit; | 
 | 	size_t old_limit; | 
 | 	size_t cp_size; | 
 | 	struct mpls_route __rcu **labels = NULL, **old; | 
 | 	struct mpls_route *rt0 = NULL, *rt2 = NULL; | 
 | 	unsigned index; | 
 |  | 
 | 	if (size) { | 
 | 		labels = kzalloc(size, GFP_KERNEL | __GFP_NOWARN | __GFP_NORETRY); | 
 | 		if (!labels) | 
 | 			labels = vzalloc(size); | 
 |  | 
 | 		if (!labels) | 
 | 			goto nolabels; | 
 | 	} | 
 |  | 
 | 	/* In case the predefined labels need to be populated */ | 
 | 	if (limit > MPLS_LABEL_IPV4NULL) { | 
 | 		struct net_device *lo = net->loopback_dev; | 
 | 		rt0 = mpls_rt_alloc(1, lo->addr_len); | 
 | 		if (!rt0) | 
 | 			goto nort0; | 
 | 		RCU_INIT_POINTER(rt0->rt_nh->nh_dev, lo); | 
 | 		rt0->rt_protocol = RTPROT_KERNEL; | 
 | 		rt0->rt_payload_type = MPT_IPV4; | 
 | 		rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE; | 
 | 		rt0->rt_nh->nh_via_alen = lo->addr_len; | 
 | 		memcpy(__mpls_nh_via(rt0, rt0->rt_nh), lo->dev_addr, | 
 | 		       lo->addr_len); | 
 | 	} | 
 | 	if (limit > MPLS_LABEL_IPV6NULL) { | 
 | 		struct net_device *lo = net->loopback_dev; | 
 | 		rt2 = mpls_rt_alloc(1, lo->addr_len); | 
 | 		if (!rt2) | 
 | 			goto nort2; | 
 | 		RCU_INIT_POINTER(rt2->rt_nh->nh_dev, lo); | 
 | 		rt2->rt_protocol = RTPROT_KERNEL; | 
 | 		rt2->rt_payload_type = MPT_IPV6; | 
 | 		rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE; | 
 | 		rt2->rt_nh->nh_via_alen = lo->addr_len; | 
 | 		memcpy(__mpls_nh_via(rt2, rt2->rt_nh), lo->dev_addr, | 
 | 		       lo->addr_len); | 
 | 	} | 
 |  | 
 | 	rtnl_lock(); | 
 | 	/* Remember the original table */ | 
 | 	old = rtnl_dereference(net->mpls.platform_label); | 
 | 	old_limit = net->mpls.platform_labels; | 
 |  | 
 | 	/* Free any labels beyond the new table */ | 
 | 	for (index = limit; index < old_limit; index++) | 
 | 		mpls_route_update(net, index, NULL, NULL); | 
 |  | 
 | 	/* Copy over the old labels */ | 
 | 	cp_size = size; | 
 | 	if (old_limit < limit) | 
 | 		cp_size = old_limit * sizeof(struct mpls_route *); | 
 |  | 
 | 	memcpy(labels, old, cp_size); | 
 |  | 
 | 	/* If needed set the predefined labels */ | 
 | 	if ((old_limit <= MPLS_LABEL_IPV6NULL) && | 
 | 	    (limit > MPLS_LABEL_IPV6NULL)) { | 
 | 		RCU_INIT_POINTER(labels[MPLS_LABEL_IPV6NULL], rt2); | 
 | 		rt2 = NULL; | 
 | 	} | 
 |  | 
 | 	if ((old_limit <= MPLS_LABEL_IPV4NULL) && | 
 | 	    (limit > MPLS_LABEL_IPV4NULL)) { | 
 | 		RCU_INIT_POINTER(labels[MPLS_LABEL_IPV4NULL], rt0); | 
 | 		rt0 = NULL; | 
 | 	} | 
 |  | 
 | 	/* Update the global pointers */ | 
 | 	net->mpls.platform_labels = limit; | 
 | 	rcu_assign_pointer(net->mpls.platform_label, labels); | 
 |  | 
 | 	rtnl_unlock(); | 
 |  | 
 | 	mpls_rt_free(rt2); | 
 | 	mpls_rt_free(rt0); | 
 |  | 
 | 	if (old) { | 
 | 		synchronize_rcu(); | 
 | 		kvfree(old); | 
 | 	} | 
 | 	return 0; | 
 |  | 
 | nort2: | 
 | 	mpls_rt_free(rt0); | 
 | nort0: | 
 | 	kvfree(labels); | 
 | nolabels: | 
 | 	return -ENOMEM; | 
 | } | 
 |  | 
 | static int mpls_platform_labels(struct ctl_table *table, int write, | 
 | 				void __user *buffer, size_t *lenp, loff_t *ppos) | 
 | { | 
 | 	struct net *net = table->data; | 
 | 	int platform_labels = net->mpls.platform_labels; | 
 | 	int ret; | 
 | 	struct ctl_table tmp = { | 
 | 		.procname	= table->procname, | 
 | 		.data		= &platform_labels, | 
 | 		.maxlen		= sizeof(int), | 
 | 		.mode		= table->mode, | 
 | 		.extra1		= &zero, | 
 | 		.extra2		= &label_limit, | 
 | 	}; | 
 |  | 
 | 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos); | 
 |  | 
 | 	if (write && ret == 0) | 
 | 		ret = resize_platform_label_table(net, platform_labels); | 
 |  | 
 | 	return ret; | 
 | } | 
 |  | 
 | static const struct ctl_table mpls_table[] = { | 
 | 	{ | 
 | 		.procname	= "platform_labels", | 
 | 		.data		= NULL, | 
 | 		.maxlen		= sizeof(int), | 
 | 		.mode		= 0644, | 
 | 		.proc_handler	= mpls_platform_labels, | 
 | 	}, | 
 | 	{ } | 
 | }; | 
 |  | 
 | static int mpls_net_init(struct net *net) | 
 | { | 
 | 	struct ctl_table *table; | 
 |  | 
 | 	net->mpls.platform_labels = 0; | 
 | 	net->mpls.platform_label = NULL; | 
 |  | 
 | 	table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL); | 
 | 	if (table == NULL) | 
 | 		return -ENOMEM; | 
 |  | 
 | 	table[0].data = net; | 
 | 	net->mpls.ctl = register_net_sysctl(net, "net/mpls", table); | 
 | 	if (net->mpls.ctl == NULL) { | 
 | 		kfree(table); | 
 | 		return -ENOMEM; | 
 | 	} | 
 |  | 
 | 	return 0; | 
 | } | 
 |  | 
 | static void mpls_net_exit(struct net *net) | 
 | { | 
 | 	struct mpls_route __rcu **platform_label; | 
 | 	size_t platform_labels; | 
 | 	struct ctl_table *table; | 
 | 	unsigned int index; | 
 |  | 
 | 	table = net->mpls.ctl->ctl_table_arg; | 
 | 	unregister_net_sysctl_table(net->mpls.ctl); | 
 | 	kfree(table); | 
 |  | 
 | 	/* An rcu grace period has passed since there was a device in | 
 | 	 * the network namespace (and thus the last in flight packet) | 
 | 	 * left this network namespace.  This is because | 
 | 	 * unregister_netdevice_many and netdev_run_todo has completed | 
 | 	 * for each network device that was in this network namespace. | 
 | 	 * | 
 | 	 * As such no additional rcu synchronization is necessary when | 
 | 	 * freeing the platform_label table. | 
 | 	 */ | 
 | 	rtnl_lock(); | 
 | 	platform_label = rtnl_dereference(net->mpls.platform_label); | 
 | 	platform_labels = net->mpls.platform_labels; | 
 | 	for (index = 0; index < platform_labels; index++) { | 
 | 		struct mpls_route *rt = rtnl_dereference(platform_label[index]); | 
 | 		RCU_INIT_POINTER(platform_label[index], NULL); | 
 | 		mpls_notify_route(net, index, rt, NULL, NULL); | 
 | 		mpls_rt_free(rt); | 
 | 	} | 
 | 	rtnl_unlock(); | 
 |  | 
 | 	kvfree(platform_label); | 
 | } | 
 |  | 
 | static struct pernet_operations mpls_net_ops = { | 
 | 	.init = mpls_net_init, | 
 | 	.exit = mpls_net_exit, | 
 | }; | 
 |  | 
 | static int __init mpls_init(void) | 
 | { | 
 | 	int err; | 
 |  | 
 | 	BUILD_BUG_ON(sizeof(struct mpls_shim_hdr) != 4); | 
 |  | 
 | 	err = register_pernet_subsys(&mpls_net_ops); | 
 | 	if (err) | 
 | 		goto out; | 
 |  | 
 | 	err = register_netdevice_notifier(&mpls_dev_notifier); | 
 | 	if (err) | 
 | 		goto out_unregister_pernet; | 
 |  | 
 | 	dev_add_pack(&mpls_packet_type); | 
 |  | 
 | 	rtnl_register(PF_MPLS, RTM_NEWROUTE, mpls_rtm_newroute, NULL, NULL); | 
 | 	rtnl_register(PF_MPLS, RTM_DELROUTE, mpls_rtm_delroute, NULL, NULL); | 
 | 	rtnl_register(PF_MPLS, RTM_GETROUTE, NULL, mpls_dump_routes, NULL); | 
 | 	err = 0; | 
 | out: | 
 | 	return err; | 
 |  | 
 | out_unregister_pernet: | 
 | 	unregister_pernet_subsys(&mpls_net_ops); | 
 | 	goto out; | 
 | } | 
 | module_init(mpls_init); | 
 |  | 
 | static void __exit mpls_exit(void) | 
 | { | 
 | 	rtnl_unregister_all(PF_MPLS); | 
 | 	dev_remove_pack(&mpls_packet_type); | 
 | 	unregister_netdevice_notifier(&mpls_dev_notifier); | 
 | 	unregister_pernet_subsys(&mpls_net_ops); | 
 | } | 
 | module_exit(mpls_exit); | 
 |  | 
 | MODULE_DESCRIPTION("MultiProtocol Label Switching"); | 
 | MODULE_LICENSE("GPL v2"); | 
 | MODULE_ALIAS_NETPROTO(PF_MPLS); |