af_mpls.c 49.5 KB
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#include <linux/types.h>
#include <linux/skbuff.h>
#include <linux/socket.h>
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#include <linux/sysctl.h>
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#include <linux/net.h>
#include <linux/module.h>
#include <linux/if_arp.h>
#include <linux/ipv6.h>
#include <linux/mpls.h>
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#include <linux/netconf.h>
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#include <linux/vmalloc.h>
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#include <linux/percpu.h>
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#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>
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#if IS_ENABLED(CONFIG_IPV6)
#include <net/ipv6.h>
#endif
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#include <net/addrconf.h>
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#include <net/nexthop.h>
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#include "internal.h"

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/* Maximum number of labels to look ahead at when selecting a path of
 * a multipath route
 */
#define MAX_MP_SELECT_LABELS 4

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#define MPLS_NEIGH_TABLE_UNSPEC (NEIGH_LINK_TABLE + 1)

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static int zero = 0;
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static int one = 1;
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static int label_limit = (1 << 20) - 1;
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static int ttl_max = 255;
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static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
		       struct nlmsghdr *nlh, struct net *net, u32 portid,
		       unsigned int nlm_flags);

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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;
}

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bool mpls_output_possible(const struct net_device *dev)
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{
	return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev);
}
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EXPORT_SYMBOL_GPL(mpls_output_possible);
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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);
}

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static unsigned int mpls_nh_header_size(const struct mpls_nh *nh)
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{
	/* The size of the layer 2.5 labels to be added for this route */
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	return nh->nh_labels * sizeof(struct mpls_shim_hdr);
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}

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unsigned int mpls_dev_mtu(const struct net_device *dev)
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{
	/* The amount of data the layer 2 frame can hold */
	return dev->mtu;
}
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EXPORT_SYMBOL_GPL(mpls_dev_mtu);
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bool mpls_pkt_too_big(const struct sk_buff *skb, unsigned int mtu)
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{
	if (skb->len <= mtu)
		return false;

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	if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu))
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		return false;

	return true;
}
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EXPORT_SYMBOL_GPL(mpls_pkt_too_big);
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void mpls_stats_inc_outucastpkts(struct net_device *dev,
				 const struct sk_buff *skb)
{
	struct mpls_dev *mdev;

	if (skb->protocol == htons(ETH_P_MPLS_UC)) {
		mdev = mpls_dev_get(dev);
		if (mdev)
			MPLS_INC_STATS_LEN(mdev, skb->len,
					   tx_packets,
					   tx_bytes);
	} else if (skb->protocol == htons(ETH_P_IP)) {
		IP_UPD_PO_STATS(dev_net(dev), IPSTATS_MIB_OUT, skb->len);
#if IS_ENABLED(CONFIG_IPV6)
	} else if (skb->protocol == htons(ETH_P_IPV6)) {
		struct inet6_dev *in6dev = __in6_dev_get(dev);

		if (in6dev)
			IP6_UPD_PO_STATS(dev_net(dev), in6dev,
					 IPSTATS_MIB_OUT, skb->len);
#endif
	}
}
EXPORT_SYMBOL_GPL(mpls_stats_inc_outucastpkts);

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static u32 mpls_multipath_hash(struct mpls_route *rt, struct sk_buff *skb)
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{
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	struct mpls_entry_decoded dec;
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	unsigned int mpls_hdr_len = 0;
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	struct mpls_shim_hdr *hdr;
	bool eli_seen = false;
	int label_index;
	u32 hash = 0;

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	for (label_index = 0; label_index < MAX_MP_SELECT_LABELS;
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	     label_index++) {
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		mpls_hdr_len += sizeof(*hdr);
		if (!pskb_may_pull(skb, mpls_hdr_len))
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			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;
		}

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		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))) {
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			const struct iphdr *v4hdr;

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			v4hdr = (const struct iphdr *)(hdr + 1);
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			if (v4hdr->version == 4) {
				hash = jhash_3words(ntohl(v4hdr->saddr),
						    ntohl(v4hdr->daddr),
						    v4hdr->protocol, hash);
			} else if (v4hdr->version == 6 &&
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				   pskb_may_pull(skb, mpls_hdr_len +
						 sizeof(struct ipv6hdr))) {
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				const struct ipv6hdr *v6hdr;

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				v6hdr = (const struct ipv6hdr *)(hdr + 1);
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				hash = __ipv6_addr_jhash(&v6hdr->saddr, hash);
				hash = __ipv6_addr_jhash(&v6hdr->daddr, hash);
				hash = jhash_1word(v6hdr->nexthdr, hash);
			}
		}
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		break;
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	}

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	return hash;
}

static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt,
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					     struct sk_buff *skb)
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{
	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;

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	hash = mpls_multipath_hash(rt, skb);
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	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);

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out:
	return &rt->rt_nh[nh_index];
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}

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static bool mpls_egress(struct net *net, struct mpls_route *rt,
			struct sk_buff *skb, struct mpls_entry_decoded dec)
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{
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	enum mpls_payload_type payload_type;
	bool success = false;
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	/* 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;

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	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);
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		u8 new_ttl;
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		skb->protocol = htons(ETH_P_IP);
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		/* If propagating TTL, take the decremented TTL from
		 * the incoming MPLS header, otherwise decrement the
		 * TTL, but only if not 0 to avoid underflow.
		 */
		if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED ||
		    (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT &&
		     net->mpls.ip_ttl_propagate))
			new_ttl = dec.ttl;
		else
			new_ttl = hdr4->ttl ? hdr4->ttl - 1 : 0;

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		csum_replace2(&hdr4->check,
			      htons(hdr4->ttl << 8),
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			      htons(new_ttl << 8));
		hdr4->ttl = new_ttl;
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		success = true;
		break;
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	}
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	case MPT_IPV6: {
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		struct ipv6hdr *hdr6 = ipv6_hdr(skb);
		skb->protocol = htons(ETH_P_IPV6);
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		/* If propagating TTL, take the decremented TTL from
		 * the incoming MPLS header, otherwise decrement the
		 * hop limit, but only if not 0 to avoid underflow.
		 */
		if (rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED ||
		    (rt->rt_ttl_propagate == MPLS_TTL_PROP_DEFAULT &&
		     net->mpls.ip_ttl_propagate))
			hdr6->hop_limit = dec.ttl;
		else if (hdr6->hop_limit)
			hdr6->hop_limit = hdr6->hop_limit - 1;
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		success = true;
		break;
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	}
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	case MPT_UNSPEC:
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		/* Should have decided which protocol it is by now */
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		break;
	}

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	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;
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	struct mpls_nh *nh;
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	struct mpls_entry_decoded dec;
	struct net_device *out_dev;
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	struct mpls_dev *out_mdev;
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	struct mpls_dev *mdev;
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	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 */

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	mdev = mpls_dev_get(dev);
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	if (!mdev)
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		goto drop;

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	MPLS_INC_STATS_LEN(mdev, skb->len, rx_packets,
			   rx_bytes);

	if (!mdev->input_enabled) {
		MPLS_INC_STATS(mdev, rx_dropped);
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		goto drop;
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	}

	if (skb->pkt_type != PACKET_HOST)
		goto err;
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	if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
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		goto err;
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	if (!pskb_may_pull(skb, sizeof(*hdr)))
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		goto err;
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	/* Read and decode the label */
	hdr = mpls_hdr(skb);
	dec = mpls_entry_decode(hdr);

	rt = mpls_route_input_rcu(net, dec.label);
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	if (!rt) {
		MPLS_INC_STATS(mdev, rx_noroute);
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		goto drop;
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	}
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	nh = mpls_select_multipath(rt, skb);
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	if (!nh)
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		goto err;
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	/* Pop the label */
	skb_pull(skb, sizeof(*hdr));
	skb_reset_network_header(skb);

	skb_orphan(skb);

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	if (skb_warn_if_lro(skb))
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		goto err;
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	skb_forward_csum(skb);

	/* Verify ttl is valid */
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	if (dec.ttl <= 1)
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		goto err;
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	dec.ttl -= 1;

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	/* Find the output device */
	out_dev = rcu_dereference(nh->nh_dev);
	if (!mpls_output_possible(out_dev))
		goto tx_err;

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	/* Verify the destination can hold the packet */
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	new_header_size = mpls_nh_header_size(nh);
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	mtu = mpls_dev_mtu(out_dev);
	if (mpls_pkt_too_big(skb, mtu - new_header_size))
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		goto tx_err;
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	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))
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		goto tx_err;
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	skb->dev = out_dev;
	skb->protocol = htons(ETH_P_MPLS_UC);

	if (unlikely(!new_header_size && dec.bos)) {
		/* Penultimate hop popping */
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		if (!mpls_egress(dev_net(out_dev), rt, skb, dec))
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			goto err;
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	} 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;
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		for (i = nh->nh_labels - 1; i >= 0; i--) {
			hdr[i] = mpls_entry_encode(nh->nh_label[i],
						   dec.ttl, 0, bos);
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			bos = false;
		}
	}

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	mpls_stats_inc_outucastpkts(out_dev, skb);

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	/* 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);
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	if (err)
		net_dbg_ratelimited("%s: packet transmission failed: %d\n",
				    __func__, err);
	return 0;

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tx_err:
	out_mdev = out_dev ? mpls_dev_get(out_dev) : NULL;
	if (out_mdev)
		MPLS_INC_STATS(out_mdev, tx_errors);
	goto drop;
err:
	MPLS_INC_STATS(mdev, rx_errors);
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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,
};

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static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = {
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	[RTA_DST]		= { .type = NLA_U32 },
	[RTA_OIF]		= { .type = NLA_U32 },
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	[RTA_TTL_PROPAGATE]	= { .type = NLA_U8 },
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};

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struct mpls_route_config {
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	u32			rc_protocol;
	u32			rc_ifindex;
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	u8			rc_via_table;
	u8			rc_via_alen;
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	u8			rc_via[MAX_VIA_ALEN];
	u32			rc_label;
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	u8			rc_ttl_propagate;
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	u8			rc_output_labels;
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	u32			rc_output_label[MAX_NEW_LABELS];
	u32			rc_nlflags;
	enum mpls_payload_type	rc_payload_type;
	struct nl_info		rc_nlinfo;
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	struct rtnexthop	*rc_mp;
	int			rc_mp_len;
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};

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static struct mpls_route *mpls_rt_alloc(int num_nh, u8 max_alen)
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{
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	u8 max_alen_aligned = ALIGN(max_alen, VIA_ALEN_ALIGN);
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	struct mpls_route *rt;

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	rt = kzalloc(ALIGN(sizeof(*rt) + num_nh * sizeof(*rt->rt_nh),
			   VIA_ALEN_ALIGN) +
		     num_nh * max_alen_aligned,
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		     GFP_KERNEL);
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	if (rt) {
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		rt->rt_nhn = num_nh;
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		rt->rt_nhn_alive = num_nh;
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		rt->rt_max_alen = max_alen_aligned;
	}
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	return rt;
}

static void mpls_rt_free(struct mpls_route *rt)
{
	if (rt)
		kfree_rcu(rt, rt_rcu);
}

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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 */
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	if (rt && (index >= MPLS_LABEL_FIRST_UNRESERVED))
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		rtmsg_lfib(event, index, rt, nlh, net, portid, nlm_flags);
}

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static void mpls_route_update(struct net *net, unsigned index,
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			      struct mpls_route *new,
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			      const struct nl_info *info)
{
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	struct mpls_route __rcu **platform_label;
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	struct mpls_route *rt;
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	ASSERT_RTNL();

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	platform_label = rtnl_dereference(net->mpls.platform_label);
	rt = rtnl_dereference(platform_label[index]);
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	rcu_assign_pointer(platform_label[index], new);
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	mpls_notify_route(net, index, rt, new, info);
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	/* If we removed a route free it now */
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	mpls_rt_free(rt);
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}

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static unsigned find_free_label(struct net *net)
{
520 521
	struct mpls_route __rcu **platform_label;
	size_t platform_labels;
522
	unsigned index;
523 524 525

	platform_label = rtnl_dereference(net->mpls.platform_label);
	platform_labels = net->mpls.platform_labels;
526 527
	for (index = MPLS_LABEL_FIRST_UNRESERVED; index < platform_labels;
	     index++) {
528
		if (!rtnl_dereference(platform_label[index]))
529 530 531 532 533
			return index;
	}
	return LABEL_NOT_SPECIFIED;
}

534
#if IS_ENABLED(CONFIG_INET)
535 536
static struct net_device *inet_fib_lookup_dev(struct net *net,
					      const void *addr)
R
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537
{
538
	struct net_device *dev;
R
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539 540 541 542 543 544
	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))
545
		return ERR_CAST(rt);
R
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546 547 548 549 550 551 552

	dev = rt->dst.dev;
	dev_hold(dev);

	ip_rt_put(rt);

	return dev;
553 554
}
#else
555 556
static struct net_device *inet_fib_lookup_dev(struct net *net,
					      const void *addr)
557 558
{
	return ERR_PTR(-EAFNOSUPPORT);
R
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559
}
560
#endif
R
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561

562
#if IS_ENABLED(CONFIG_IPV6)
563 564
static struct net_device *inet6_fib_lookup_dev(struct net *net,
					       const void *addr)
R
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565
{
566
	struct net_device *dev;
R
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567 568
	struct dst_entry *dst;
	struct flowi6 fl6;
569 570 571 572
	int err;

	if (!ipv6_stub)
		return ERR_PTR(-EAFNOSUPPORT);
R
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573 574 575

	memset(&fl6, 0, sizeof(fl6));
	memcpy(&fl6.daddr, addr, sizeof(struct in6_addr));
576 577
	err = ipv6_stub->ipv6_dst_lookup(net, NULL, &dst, &fl6);
	if (err)
578
		return ERR_PTR(err);
R
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579 580 581 582 583 584 585

	dev = dst->dev;
	dev_hold(dev);
	dst_release(dst);

	return dev;
}
586
#else
587 588
static struct net_device *inet6_fib_lookup_dev(struct net *net,
					       const void *addr)
589 590 591 592
{
	return ERR_PTR(-EAFNOSUPPORT);
}
#endif
R
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593 594

static struct net_device *find_outdev(struct net *net,
595
				      struct mpls_route *rt,
R
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596
				      struct mpls_nh *nh, int oif)
R
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597 598 599
{
	struct net_device *dev = NULL;

R
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600 601
	if (!oif) {
		switch (nh->nh_via_table) {
R
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602
		case NEIGH_ARP_TABLE:
603
			dev = inet_fib_lookup_dev(net, mpls_nh_via(rt, nh));
R
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604 605
			break;
		case NEIGH_ND_TABLE:
606
			dev = inet6_fib_lookup_dev(net, mpls_nh_via(rt, nh));
R
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607 608 609 610 611
			break;
		case NEIGH_LINK_TABLE:
			break;
		}
	} else {
R
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612
		dev = dev_get_by_index(net, oif);
R
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613 614
	}

615 616 617
	if (!dev)
		return ERR_PTR(-ENODEV);

618 619 620
	if (IS_ERR(dev))
		return dev;

R
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621 622 623
	/* The caller is holding rtnl anyways, so release the dev reference */
	dev_put(dev);

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624 625 626
	return dev;
}

627 628
static int mpls_nh_assign_dev(struct net *net, struct mpls_route *rt,
			      struct mpls_nh *nh, int oif)
R
Roopa Prabhu 已提交
629 630 631 632
{
	struct net_device *dev = NULL;
	int err = -ENODEV;

633
	dev = find_outdev(net, rt, nh, oif);
R
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634 635 636 637 638 639 640 641 642 643 644
	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;

645 646 647 648
	if ((nh->nh_via_table == NEIGH_LINK_TABLE) &&
	    (dev->addr_len != nh->nh_via_alen))
		goto errout;

R
Roopa Prabhu 已提交
649 650
	RCU_INIT_POINTER(nh->nh_dev, dev);

R
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651 652 653 654 655 656 657 658 659 660
	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;
	}

R
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661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687
	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;
688
	memcpy(__mpls_nh_via(rt, nh), cfg->rc_via, cfg->rc_via_alen);
R
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689 690
	nh->nh_via_alen = cfg->rc_via_alen;

691
	err = mpls_nh_assign_dev(net, rt, nh, cfg->rc_ifindex);
R
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692 693 694
	if (err)
		goto errout;

R
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695 696 697
	if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
		rt->rt_nhn_alive--;

R
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698 699 700 701 702 703
	return 0;

errout:
	return err;
}

704
static int mpls_nh_build(struct net *net, struct mpls_route *rt,
R
Roopa Prabhu 已提交
705 706
			 struct mpls_nh *nh, int oif, struct nlattr *via,
			 struct nlattr *newdst)
R
Roopa Prabhu 已提交
707 708 709 710 711 712 713 714 715 716 717 718 719
{
	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;
	}

720 721 722 723 724 725 726 727
	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;
	}
R
Roopa Prabhu 已提交
728

729
	err = mpls_nh_assign_dev(net, rt, nh, oif);
R
Roopa Prabhu 已提交
730 731 732 733 734 735 736 737 738
	if (err)
		goto errout;

	return 0;

errout:
	return err;
}

739 740
static int mpls_count_nexthops(struct rtnexthop *rtnh, int len,
			       u8 cfg_via_alen, u8 *max_via_alen)
R
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741 742 743 744
{
	int nhs = 0;
	int remaining = len;

745 746 747 748 749 750 751
	if (!rtnh) {
		*max_via_alen = cfg_via_alen;
		return 1;
	}

	*max_via_alen = 0;

R
Roopa Prabhu 已提交
752
	while (rtnh_ok(rtnh, remaining)) {
753 754 755 756 757 758 759 760 761 762 763 764 765 766 767
		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);
		}

R
Roopa Prabhu 已提交
768 769 770 771 772 773 774 775 776 777 778 779 780 781 782 783 784 785 786 787 788 789 790 791 792 793 794
		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;

795 796 797 798 799 800
		/* neither weighted multipath nor any flags
		 * are supported
		 */
		if (rtnh->rtnh_hops || rtnh->rtnh_flags)
			goto errout;

R
Roopa Prabhu 已提交
801 802 803 804 805 806 807 808
		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);
		}

809
		err = mpls_nh_build(cfg->rc_nlinfo.nl_net, rt, nh,
R
Roopa Prabhu 已提交
810
				    rtnh->rtnh_ifindex, nla_via, nla_newdst);
R
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811 812 813
		if (err)
			goto errout;

R
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814 815 816
		if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
			rt->rt_nhn_alive--;

R
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817 818 819 820 821 822 823 824 825 826 827 828
		rtnh = rtnh_next(rtnh, &remaining);
		nhs++;
	} endfor_nexthops(rt);

	rt->rt_nhn = nhs;

	return 0;

errout:
	return err;
}

829 830
static int mpls_route_add(struct mpls_route_config *cfg)
{
831
	struct mpls_route __rcu **platform_label;
832 833 834
	struct net *net = cfg->rc_nlinfo.nl_net;
	struct mpls_route *rt, *old;
	int err = -EINVAL;
835
	u8 max_via_alen;
R
Roopa Prabhu 已提交
836
	unsigned index;
837
	int nhs;
838 839 840 841 842 843 844 845 846

	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);
	}

847 848
	/* Reserved labels may not be set */
	if (index < MPLS_LABEL_FIRST_UNRESERVED)
849 850 851 852 853 854 855
		goto errout;

	/* The full 20 bit range may not be supported. */
	if (index >= net->mpls.platform_labels)
		goto errout;

	/* Append makes no sense with mpls */
856
	err = -EOPNOTSUPP;
857 858 859 860
	if (cfg->rc_nlflags & NLM_F_APPEND)
		goto errout;

	err = -EEXIST;
861 862
	platform_label = rtnl_dereference(net->mpls.platform_label);
	old = rtnl_dereference(platform_label[index]);
863 864 865 866 867 868 869 870 871 872 873
	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;

874 875 876 877 878
	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;
R
Roopa Prabhu 已提交
879

880
	err = -ENOMEM;
881
	rt = mpls_rt_alloc(nhs, max_via_alen);
882 883 884 885
	if (!rt)
		goto errout;

	rt->rt_protocol = cfg->rc_protocol;
886
	rt->rt_payload_type = cfg->rc_payload_type;
887
	rt->rt_ttl_propagate = cfg->rc_ttl_propagate;
888

R
Roopa Prabhu 已提交
889 890 891 892 893 894 895 896
	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);
897 898 899

	return 0;

R
Roopa Prabhu 已提交
900 901
freert:
	mpls_rt_free(rt);
902 903 904 905 906 907 908 909 910 911 912 913
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;

914 915
	/* Reserved labels may not be removed */
	if (index < MPLS_LABEL_FIRST_UNRESERVED)
916 917 918 919 920 921
		goto errout;

	/* The full 20 bit range may not be supported */
	if (index >= net->mpls.platform_labels)
		goto errout;

R
Roopa Prabhu 已提交
922
	mpls_route_update(net, index, NULL, &cfg->rc_nlinfo);
923 924 925 926 927 928

	err = 0;
errout:
	return err;
}

R
Robert Shearman 已提交
929 930 931 932 933 934 935 936 937 938 939 940 941 942 943 944 945 946 947 948 949 950 951 952 953 954 955 956 957 958 959 960 961 962 963 964 965 966 967 968 969 970 971 972 973 974 975 976 977 978 979 980 981 982 983 984 985 986 987 988 989 990 991 992
static void mpls_get_stats(struct mpls_dev *mdev,
			   struct mpls_link_stats *stats)
{
	struct mpls_pcpu_stats *p;
	int i;

	memset(stats, 0, sizeof(*stats));

	for_each_possible_cpu(i) {
		struct mpls_link_stats local;
		unsigned int start;

		p = per_cpu_ptr(mdev->stats, i);
		do {
			start = u64_stats_fetch_begin(&p->syncp);
			local = p->stats;
		} while (u64_stats_fetch_retry(&p->syncp, start));

		stats->rx_packets	+= local.rx_packets;
		stats->rx_bytes		+= local.rx_bytes;
		stats->tx_packets	+= local.tx_packets;
		stats->tx_bytes		+= local.tx_bytes;
		stats->rx_errors	+= local.rx_errors;
		stats->tx_errors	+= local.tx_errors;
		stats->rx_dropped	+= local.rx_dropped;
		stats->tx_dropped	+= local.tx_dropped;
		stats->rx_noroute	+= local.rx_noroute;
	}
}

static int mpls_fill_stats_af(struct sk_buff *skb,
			      const struct net_device *dev)
{
	struct mpls_link_stats *stats;
	struct mpls_dev *mdev;
	struct nlattr *nla;

	mdev = mpls_dev_get(dev);
	if (!mdev)
		return -ENODATA;

	nla = nla_reserve_64bit(skb, MPLS_STATS_LINK,
				sizeof(struct mpls_link_stats),
				MPLS_STATS_UNSPEC);
	if (!nla)
		return -EMSGSIZE;

	stats = nla_data(nla);
	mpls_get_stats(mdev, stats);

	return 0;
}

static size_t mpls_get_stats_af_size(const struct net_device *dev)
{
	struct mpls_dev *mdev;

	mdev = mpls_dev_get(dev);
	if (!mdev)
		return 0;

	return nla_total_size_64bit(sizeof(struct mpls_link_stats));
}

D
David Ahern 已提交
993 994 995 996 997 998 999 1000 1001 1002 1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 1028 1029 1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041 1042 1043 1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097 1098 1099 1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150 1151 1152 1153 1154 1155 1156 1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168
static int mpls_netconf_fill_devconf(struct sk_buff *skb, struct mpls_dev *mdev,
				     u32 portid, u32 seq, int event,
				     unsigned int flags, int type)
{
	struct nlmsghdr  *nlh;
	struct netconfmsg *ncm;
	bool all = false;

	nlh = nlmsg_put(skb, portid, seq, event, sizeof(struct netconfmsg),
			flags);
	if (!nlh)
		return -EMSGSIZE;

	if (type == NETCONFA_ALL)
		all = true;

	ncm = nlmsg_data(nlh);
	ncm->ncm_family = AF_MPLS;

	if (nla_put_s32(skb, NETCONFA_IFINDEX, mdev->dev->ifindex) < 0)
		goto nla_put_failure;

	if ((all || type == NETCONFA_INPUT) &&
	    nla_put_s32(skb, NETCONFA_INPUT,
			mdev->input_enabled) < 0)
		goto nla_put_failure;

	nlmsg_end(skb, nlh);
	return 0;

nla_put_failure:
	nlmsg_cancel(skb, nlh);
	return -EMSGSIZE;
}

static int mpls_netconf_msgsize_devconf(int type)
{
	int size = NLMSG_ALIGN(sizeof(struct netconfmsg))
			+ nla_total_size(4); /* NETCONFA_IFINDEX */
	bool all = false;

	if (type == NETCONFA_ALL)
		all = true;

	if (all || type == NETCONFA_INPUT)
		size += nla_total_size(4);

	return size;
}

static void mpls_netconf_notify_devconf(struct net *net, int type,
					struct mpls_dev *mdev)
{
	struct sk_buff *skb;
	int err = -ENOBUFS;

	skb = nlmsg_new(mpls_netconf_msgsize_devconf(type), GFP_KERNEL);
	if (!skb)
		goto errout;

	err = mpls_netconf_fill_devconf(skb, mdev, 0, 0, RTM_NEWNETCONF,
					0, type);
	if (err < 0) {
		/* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto errout;
	}

	rtnl_notify(skb, net, 0, RTNLGRP_MPLS_NETCONF, NULL, GFP_KERNEL);
	return;
errout:
	if (err < 0)
		rtnl_set_sk_err(net, RTNLGRP_MPLS_NETCONF, err);
}

static const struct nla_policy devconf_mpls_policy[NETCONFA_MAX + 1] = {
	[NETCONFA_IFINDEX]	= { .len = sizeof(int) },
};

static int mpls_netconf_get_devconf(struct sk_buff *in_skb,
				    struct nlmsghdr *nlh)
{
	struct net *net = sock_net(in_skb->sk);
	struct nlattr *tb[NETCONFA_MAX + 1];
	struct netconfmsg *ncm;
	struct net_device *dev;
	struct mpls_dev *mdev;
	struct sk_buff *skb;
	int ifindex;
	int err;

	err = nlmsg_parse(nlh, sizeof(*ncm), tb, NETCONFA_MAX,
			  devconf_mpls_policy);
	if (err < 0)
		goto errout;

	err = -EINVAL;
	if (!tb[NETCONFA_IFINDEX])
		goto errout;

	ifindex = nla_get_s32(tb[NETCONFA_IFINDEX]);
	dev = __dev_get_by_index(net, ifindex);
	if (!dev)
		goto errout;

	mdev = mpls_dev_get(dev);
	if (!mdev)
		goto errout;

	err = -ENOBUFS;
	skb = nlmsg_new(mpls_netconf_msgsize_devconf(NETCONFA_ALL), GFP_KERNEL);
	if (!skb)
		goto errout;

	err = mpls_netconf_fill_devconf(skb, mdev,
					NETLINK_CB(in_skb).portid,
					nlh->nlmsg_seq, RTM_NEWNETCONF, 0,
					NETCONFA_ALL);
	if (err < 0) {
		/* -EMSGSIZE implies BUG in mpls_netconf_msgsize_devconf() */
		WARN_ON(err == -EMSGSIZE);
		kfree_skb(skb);
		goto errout;
	}
	err = rtnl_unicast(skb, net, NETLINK_CB(in_skb).portid);
errout:
	return err;
}

static int mpls_netconf_dump_devconf(struct sk_buff *skb,
				     struct netlink_callback *cb)
{
	struct net *net = sock_net(skb->sk);
	struct hlist_head *head;
	struct net_device *dev;
	struct mpls_dev *mdev;
	int idx, s_idx;
	int h, s_h;

	s_h = cb->args[0];
	s_idx = idx = cb->args[1];

	for (h = s_h; h < NETDEV_HASHENTRIES; h++, s_idx = 0) {
		idx = 0;
		head = &net->dev_index_head[h];
		rcu_read_lock();
		cb->seq = net->dev_base_seq;
		hlist_for_each_entry_rcu(dev, head, index_hlist) {
			if (idx < s_idx)
				goto cont;
			mdev = mpls_dev_get(dev);
			if (!mdev)
				goto cont;
			if (mpls_netconf_fill_devconf(skb, mdev,
						      NETLINK_CB(cb->skb).portid,
						      cb->nlh->nlmsg_seq,
						      RTM_NEWNETCONF,
						      NLM_F_MULTI,
						      NETCONFA_ALL) < 0) {
				rcu_read_unlock();
				goto done;
			}
			nl_dump_check_consistent(cb, nlmsg_hdr(skb));
cont:
			idx++;
		}
		rcu_read_unlock();
	}
done:
	cb->args[0] = h;
	cb->args[1] = idx;

	return skb->len;
}

1169 1170 1171
#define MPLS_PERDEV_SYSCTL_OFFSET(field)	\
	(&((struct mpls_dev *)0)->field)

D
David Ahern 已提交
1172 1173 1174 1175 1176 1177 1178 1179 1180 1181 1182 1183 1184 1185 1186 1187 1188 1189 1190 1191 1192 1193 1194 1195
static int mpls_conf_proc(struct ctl_table *ctl, int write,
			  void __user *buffer,
			  size_t *lenp, loff_t *ppos)
{
	int oval = *(int *)ctl->data;
	int ret = proc_dointvec(ctl, write, buffer, lenp, ppos);

	if (write) {
		struct mpls_dev *mdev = ctl->extra1;
		int i = (int *)ctl->data - (int *)mdev;
		struct net *net = ctl->extra2;
		int val = *(int *)ctl->data;

		if (i == offsetof(struct mpls_dev, input_enabled) &&
		    val != oval) {
			mpls_netconf_notify_devconf(net,
						    NETCONFA_INPUT,
						    mdev);
		}
	}

	return ret;
}

1196 1197 1198 1199 1200
static const struct ctl_table mpls_dev_table[] = {
	{
		.procname	= "input",
		.maxlen		= sizeof(int),
		.mode		= 0644,
D
David Ahern 已提交
1201
		.proc_handler	= mpls_conf_proc,
1202 1203 1204 1205 1206 1207 1208 1209 1210
		.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];
D
David Ahern 已提交
1211
	struct net *net = dev_net(dev);
1212 1213 1214 1215 1216 1217 1218 1219 1220 1221
	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.
	 */
D
David Ahern 已提交
1222
	for (i = 0; i < ARRAY_SIZE(mpls_dev_table); i++) {
1223
		table[i].data = (char *)mdev + (uintptr_t)table[i].data;
D
David Ahern 已提交
1224 1225 1226
		table[i].extra1 = mdev;
		table[i].extra2 = net;
	}
1227 1228 1229 1230 1231 1232 1233 1234 1235 1236 1237 1238 1239 1240 1241 1242 1243 1244 1245 1246 1247 1248 1249 1250

	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);
}

R
Robert Shearman 已提交
1251 1252 1253 1254
static struct mpls_dev *mpls_add_dev(struct net_device *dev)
{
	struct mpls_dev *mdev;
	int err = -ENOMEM;
R
Robert Shearman 已提交
1255
	int i;
R
Robert Shearman 已提交
1256 1257 1258 1259 1260 1261 1262

	ASSERT_RTNL();

	mdev = kzalloc(sizeof(*mdev), GFP_KERNEL);
	if (!mdev)
		return ERR_PTR(err);

R
Robert Shearman 已提交
1263 1264 1265 1266 1267 1268 1269 1270 1271 1272 1273
	mdev->stats = alloc_percpu(struct mpls_pcpu_stats);
	if (!mdev->stats)
		goto free;

	for_each_possible_cpu(i) {
		struct mpls_pcpu_stats *mpls_stats;

		mpls_stats = per_cpu_ptr(mdev->stats, i);
		u64_stats_init(&mpls_stats->syncp);
	}

1274 1275 1276 1277
	err = mpls_dev_sysctl_register(dev, mdev);
	if (err)
		goto free;

D
David Ahern 已提交
1278
	mdev->dev = dev;
R
Robert Shearman 已提交
1279 1280 1281
	rcu_assign_pointer(dev->mpls_ptr, mdev);

	return mdev;
1282 1283

free:
R
Robert Shearman 已提交
1284
	free_percpu(mdev->stats);
1285 1286
	kfree(mdev);
	return ERR_PTR(err);
R
Robert Shearman 已提交
1287 1288
}

R
Robert Shearman 已提交
1289 1290 1291 1292 1293 1294 1295 1296
static void mpls_dev_destroy_rcu(struct rcu_head *head)
{
	struct mpls_dev *mdev = container_of(head, struct mpls_dev, rcu);

	free_percpu(mdev->stats);
	kfree(mdev);
}

R
Roopa Prabhu 已提交
1297
static void mpls_ifdown(struct net_device *dev, int event)
E
Eric W. Biederman 已提交
1298
{
1299
	struct mpls_route __rcu **platform_label;
E
Eric W. Biederman 已提交
1300
	struct net *net = dev_net(dev);
1301 1302
	unsigned int nh_flags = RTNH_F_DEAD | RTNH_F_LINKDOWN;
	unsigned int alive;
E
Eric W. Biederman 已提交
1303 1304
	unsigned index;

1305
	platform_label = rtnl_dereference(net->mpls.platform_label);
E
Eric W. Biederman 已提交
1306
	for (index = 0; index < net->mpls.platform_labels; index++) {
1307
		struct mpls_route *rt = rtnl_dereference(platform_label[index]);
R
Roopa Prabhu 已提交
1308

E
Eric W. Biederman 已提交
1309 1310
		if (!rt)
			continue;
R
Roopa Prabhu 已提交
1311

1312
		alive = 0;
R
Roopa Prabhu 已提交
1313
		change_nexthops(rt) {
R
Roopa Prabhu 已提交
1314
			if (rtnl_dereference(nh->nh_dev) != dev)
1315 1316
				goto next;

R
Roopa Prabhu 已提交
1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327
			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);
1328 1329 1330
next:
			if (!(nh->nh_flags & nh_flags))
				alive++;
R
Roopa Prabhu 已提交
1331
		} endfor_nexthops(rt);
1332 1333

		WRITE_ONCE(rt->rt_nhn_alive, alive);
E
Eric W. Biederman 已提交
1334
	}
R
Roopa Prabhu 已提交
1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349
}

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;
1350

R
Roopa Prabhu 已提交
1351 1352 1353 1354
		alive = 0;
		change_nexthops(rt) {
			struct net_device *nh_dev =
				rtnl_dereference(nh->nh_dev);
R
Robert Shearman 已提交
1355

R
Roopa Prabhu 已提交
1356 1357 1358 1359 1360 1361 1362 1363 1364 1365 1366 1367
			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;
	}
E
Eric W. Biederman 已提交
1368 1369 1370 1371 1372 1373
}

static int mpls_dev_notify(struct notifier_block *this, unsigned long event,
			   void *ptr)
{
	struct net_device *dev = netdev_notifier_info_to_dev(ptr);
R
Robert Shearman 已提交
1374
	struct mpls_dev *mdev;
R
Roopa Prabhu 已提交
1375
	unsigned int flags;
E
Eric W. Biederman 已提交
1376

R
Roopa Prabhu 已提交
1377
	if (event == NETDEV_REGISTER) {
1378
		/* For now just support Ethernet, IPGRE, SIT and IPIP devices */
1379 1380
		if (dev->type == ARPHRD_ETHER ||
		    dev->type == ARPHRD_LOOPBACK ||
1381 1382 1383
		    dev->type == ARPHRD_IPGRE ||
		    dev->type == ARPHRD_SIT ||
		    dev->type == ARPHRD_TUNNEL) {
R
Robert Shearman 已提交
1384 1385 1386 1387
			mdev = mpls_add_dev(dev);
			if (IS_ERR(mdev))
				return notifier_from_errno(PTR_ERR(mdev));
		}
R
Roopa Prabhu 已提交
1388 1389
		return NOTIFY_OK;
	}
R
Robert Shearman 已提交
1390

R
Roopa Prabhu 已提交
1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407 1408 1409 1410 1411 1412
	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;
E
Eric W. Biederman 已提交
1413
	case NETDEV_UNREGISTER:
R
Roopa Prabhu 已提交
1414 1415 1416 1417 1418
		mpls_ifdown(dev, event);
		mdev = mpls_dev_get(dev);
		if (mdev) {
			mpls_dev_sysctl_unregister(mdev);
			RCU_INIT_POINTER(dev->mpls_ptr, NULL);
R
Robert Shearman 已提交
1419
			call_rcu(&mdev->rcu, mpls_dev_destroy_rcu);
R
Roopa Prabhu 已提交
1420
		}
E
Eric W. Biederman 已提交
1421
		break;
1422 1423 1424 1425 1426 1427 1428 1429 1430 1431 1432
	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;
E
Eric W. Biederman 已提交
1433 1434 1435 1436 1437 1438 1439 1440
	}
	return NOTIFY_OK;
}

static struct notifier_block mpls_dev_notifier = {
	.notifier_call = mpls_dev_notify,
};

1441
static int nla_put_via(struct sk_buff *skb,
1442
		       u8 table, const void *addr, int alen)
1443
{
1444 1445 1446
	static const int table_to_family[NEIGH_NR_TABLES + 1] = {
		AF_INET, AF_INET6, AF_DECnet, AF_PACKET,
	};
1447 1448
	struct nlattr *nla;
	struct rtvia *via;
1449
	int family = AF_UNSPEC;
1450 1451 1452 1453 1454

	nla = nla_reserve(skb, RTA_VIA, alen + 2);
	if (!nla)
		return -EMSGSIZE;

1455 1456 1457
	if (table <= NEIGH_NR_TABLES)
		family = table_to_family[table];

1458 1459 1460 1461 1462 1463
	via = nla_data(nla);
	via->rtvia_family = family;
	memcpy(via->rtvia_addr, addr, alen);
	return 0;
}

1464 1465 1466 1467 1468 1469 1470 1471 1472 1473 1474 1475 1476 1477 1478 1479 1480 1481 1482 1483
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;
}
1484
EXPORT_SYMBOL_GPL(nla_put_labels);
1485 1486

int nla_get_labels(const struct nlattr *nla,
R
Roopa Prabhu 已提交
1487
		   u32 max_labels, u8 *labels, u32 label[])
1488 1489 1490 1491 1492 1493 1494 1495 1496 1497 1498 1499 1500 1501 1502 1503 1504 1505 1506 1507 1508 1509 1510 1511 1512 1513 1514 1515
{
	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;

1516
		switch (dec.label) {
1517
		case MPLS_LABEL_IMPLNULL:
1518 1519 1520 1521 1522 1523 1524
			/* RFC3032: This is a label that an LSR may
			 * assign and distribute, but which never
			 * actually appears in the encapsulation.
			 */
			return -EINVAL;
		}

1525 1526 1527 1528 1529
		label[i] = dec.label;
	}
	*labels = nla_labels;
	return 0;
}
1530
EXPORT_SYMBOL_GPL(nla_get_labels);
1531

R
Roopa Prabhu 已提交
1532 1533 1534 1535 1536 1537 1538 1539 1540 1541 1542 1543 1544 1545 1546 1547 1548 1549 1550 1551 1552 1553 1554 1555 1556 1557 1558 1559 1560 1561 1562 1563 1564 1565 1566 1567 1568 1569 1570 1571 1572 1573
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;
}

1574 1575 1576 1577 1578 1579 1580 1581 1582 1583 1584 1585 1586 1587 1588 1589 1590 1591 1592 1593 1594 1595 1596 1597 1598 1599 1600 1601 1602 1603 1604 1605 1606 1607 1608 1609 1610 1611 1612 1613 1614
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;
1615
	cfg->rc_via_table	= MPLS_NEIGH_TABLE_UNSPEC;
1616
	cfg->rc_ttl_propagate	= MPLS_TTL_PROP_DEFAULT;
1617 1618 1619 1620 1621 1622 1623 1624 1625 1626
	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;

1627
		switch (index) {
1628 1629 1630 1631 1632 1633 1634 1635 1636 1637 1638
		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:
		{
R
Roopa Prabhu 已提交
1639
			u8 label_count;
1640 1641 1642 1643
			if (nla_get_labels(nla, 1, &label_count,
					   &cfg->rc_label))
				goto errout;

1644 1645
			/* Reserved labels may not be set */
			if (cfg->rc_label < MPLS_LABEL_FIRST_UNRESERVED)
1646 1647 1648 1649 1650 1651
				goto errout;

			break;
		}
		case RTA_VIA:
		{
R
Roopa Prabhu 已提交
1652 1653
			if (nla_get_via(nla, &cfg->rc_via_alen,
					&cfg->rc_via_table, cfg->rc_via))
1654
				goto errout;
R
Roopa Prabhu 已提交
1655 1656 1657 1658 1659 1660
			break;
		}
		case RTA_MULTIPATH:
		{
			cfg->rc_mp = nla_data(nla);
			cfg->rc_mp_len = nla_len(nla);
1661 1662
			break;
		}
1663 1664 1665 1666 1667 1668 1669 1670 1671 1672 1673
		case RTA_TTL_PROPAGATE:
		{
			u8 ttl_propagate = nla_get_u8(nla);

			if (ttl_propagate > 1)
				goto errout;
			cfg->rc_ttl_propagate = ttl_propagate ?
				MPLS_TTL_PROP_ENABLED :
				MPLS_TTL_PROP_DISABLED;
			break;
		}
1674 1675 1676 1677 1678 1679 1680 1681 1682 1683 1684 1685 1686 1687 1688 1689 1690 1691 1692 1693 1694 1695 1696 1697 1698 1699 1700 1701 1702 1703 1704 1705 1706 1707 1708 1709 1710 1711 1712
		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)
{
1713
	struct net_device *dev;
1714 1715 1716 1717 1718 1719 1720 1721 1722 1723 1724 1725 1726 1727 1728 1729 1730 1731 1732 1733
	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;
1734 1735 1736 1737 1738 1739 1740 1741 1742

	if (rt->rt_ttl_propagate != MPLS_TTL_PROP_DEFAULT) {
		bool ttl_propagate =
			rt->rt_ttl_propagate == MPLS_TTL_PROP_ENABLED;

		if (nla_put_u8(skb, RTA_TTL_PROPAGATE,
			       ttl_propagate))
			goto nla_put_failure;
	}
R
Roopa Prabhu 已提交
1743
	if (rt->rt_nhn == 1) {
1744
		const struct mpls_nh *nh = rt->rt_nh;
R
Roopa Prabhu 已提交
1745 1746 1747 1748 1749

		if (nh->nh_labels &&
		    nla_put_labels(skb, RTA_NEWDST, nh->nh_labels,
				   nh->nh_label))
			goto nla_put_failure;
1750
		if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
1751
		    nla_put_via(skb, nh->nh_via_table, mpls_nh_via(rt, nh),
R
Roopa Prabhu 已提交
1752 1753 1754 1755 1756
				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;
R
Roopa Prabhu 已提交
1757 1758 1759 1760
		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;
R
Roopa Prabhu 已提交
1761 1762 1763
	} else {
		struct rtnexthop *rtnh;
		struct nlattr *mp;
R
Roopa Prabhu 已提交
1764 1765
		int dead = 0;
		int linkdown = 0;
R
Roopa Prabhu 已提交
1766 1767 1768 1769 1770 1771 1772 1773 1774 1775 1776 1777 1778

		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;
R
Roopa Prabhu 已提交
1779 1780 1781 1782 1783 1784 1785 1786 1787
			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++;
			}

R
Roopa Prabhu 已提交
1788 1789 1790 1791
			if (nh->nh_labels && nla_put_labels(skb, RTA_NEWDST,
							    nh->nh_labels,
							    nh->nh_label))
				goto nla_put_failure;
1792 1793
			if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC &&
			    nla_put_via(skb, nh->nh_via_table,
1794
					mpls_nh_via(rt, nh),
R
Roopa Prabhu 已提交
1795 1796 1797 1798 1799 1800 1801
					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);

R
Roopa Prabhu 已提交
1802 1803 1804 1805 1806
		if (linkdown == rt->rt_nhn)
			rtm->rtm_flags |= RTNH_F_LINKDOWN;
		if (dead == rt->rt_nhn)
			rtm->rtm_flags |= RTNH_F_DEAD;

R
Roopa Prabhu 已提交
1807 1808
		nla_nest_end(skb, mp);
	}
1809 1810 1811 1812 1813 1814 1815 1816 1817 1818 1819 1820

	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);
1821 1822
	struct mpls_route __rcu **platform_label;
	size_t platform_labels;
1823 1824 1825 1826 1827
	unsigned int index;

	ASSERT_RTNL();

	index = cb->args[0];
1828 1829
	if (index < MPLS_LABEL_FIRST_UNRESERVED)
		index = MPLS_LABEL_FIRST_UNRESERVED;
1830

1831 1832 1833
	platform_label = rtnl_dereference(net->mpls.platform_label);
	platform_labels = net->mpls.platform_labels;
	for (; index < platform_labels; index++) {
1834
		struct mpls_route *rt;
1835
		rt = rtnl_dereference(platform_label[index]);
1836 1837 1838 1839 1840 1841 1842 1843 1844 1845 1846 1847 1848
		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;
}

1849 1850 1851 1852
static inline size_t lfib_nlmsg_size(struct mpls_route *rt)
{
	size_t payload =
		NLMSG_ALIGN(sizeof(struct rtmsg))
1853 1854
		+ nla_total_size(4)			/* RTA_DST */
		+ nla_total_size(1);			/* RTA_TTL_PROPAGATE */
R
Roopa Prabhu 已提交
1855 1856 1857 1858 1859 1860

	if (rt->rt_nhn == 1) {
		struct mpls_nh *nh = rt->rt_nh;

		if (nh->nh_dev)
			payload += nla_total_size(4); /* RTA_OIF */
1861
		if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC) /* RTA_VIA */
1862
			payload += nla_total_size(2 + nh->nh_via_alen);
R
Roopa Prabhu 已提交
1863 1864 1865 1866 1867 1868 1869 1870
		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));
1871 1872 1873
			/* RTA_VIA */
			if (nh->nh_via_table != MPLS_NEIGH_TABLE_UNSPEC)
				nhsize += nla_total_size(2 + nh->nh_via_alen);
R
Roopa Prabhu 已提交
1874 1875 1876 1877 1878 1879 1880
			if (nh->nh_labels)
				nhsize += nla_total_size(nh->nh_labels * 4);
		} endfor_nexthops(rt);
		/* nested attribute */
		payload += nla_total_size(nhsize);
	}

1881 1882 1883 1884 1885 1886 1887 1888 1889 1890 1891 1892 1893 1894 1895 1896 1897 1898 1899 1900 1901 1902 1903 1904 1905 1906 1907 1908 1909 1910
	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);
}

1911 1912 1913 1914 1915 1916 1917 1918 1919 1920 1921 1922 1923 1924 1925 1926 1927 1928 1929
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 */
1930
	if (limit > MPLS_LABEL_IPV4NULL) {
1931
		struct net_device *lo = net->loopback_dev;
1932
		rt0 = mpls_rt_alloc(1, lo->addr_len);
1933 1934
		if (!rt0)
			goto nort0;
R
Roopa Prabhu 已提交
1935
		RCU_INIT_POINTER(rt0->rt_nh->nh_dev, lo);
1936
		rt0->rt_protocol = RTPROT_KERNEL;
1937
		rt0->rt_payload_type = MPT_IPV4;
1938
		rt0->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT;
R
Roopa Prabhu 已提交
1939
		rt0->rt_nh->nh_via_table = NEIGH_LINK_TABLE;
1940
		rt0->rt_nh->nh_via_alen = lo->addr_len;
1941 1942
		memcpy(__mpls_nh_via(rt0, rt0->rt_nh), lo->dev_addr,
		       lo->addr_len);
1943
	}
1944
	if (limit > MPLS_LABEL_IPV6NULL) {
1945
		struct net_device *lo = net->loopback_dev;
1946
		rt2 = mpls_rt_alloc(1, lo->addr_len);
1947 1948
		if (!rt2)
			goto nort2;
R
Roopa Prabhu 已提交
1949
		RCU_INIT_POINTER(rt2->rt_nh->nh_dev, lo);
1950
		rt2->rt_protocol = RTPROT_KERNEL;
1951
		rt2->rt_payload_type = MPT_IPV6;
1952
		rt0->rt_ttl_propagate = MPLS_TTL_PROP_DEFAULT;
R
Roopa Prabhu 已提交
1953
		rt2->rt_nh->nh_via_table = NEIGH_LINK_TABLE;
1954
		rt2->rt_nh->nh_via_alen = lo->addr_len;
1955 1956
		memcpy(__mpls_nh_via(rt2, rt2->rt_nh), lo->dev_addr,
		       lo->addr_len);
1957 1958 1959 1960
	}

	rtnl_lock();
	/* Remember the original table */
1961
	old = rtnl_dereference(net->mpls.platform_label);
1962 1963 1964 1965
	old_limit = net->mpls.platform_labels;

	/* Free any labels beyond the new table */
	for (index = limit; index < old_limit; index++)
R
Roopa Prabhu 已提交
1966
		mpls_route_update(net, index, NULL, NULL);
1967 1968 1969 1970 1971 1972 1973 1974 1975

	/* 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 */
1976 1977 1978
	if ((old_limit <= MPLS_LABEL_IPV6NULL) &&
	    (limit > MPLS_LABEL_IPV6NULL)) {
		RCU_INIT_POINTER(labels[MPLS_LABEL_IPV6NULL], rt2);
1979 1980 1981
		rt2 = NULL;
	}

1982 1983 1984
	if ((old_limit <= MPLS_LABEL_IPV4NULL) &&
	    (limit > MPLS_LABEL_IPV4NULL)) {
		RCU_INIT_POINTER(labels[MPLS_LABEL_IPV4NULL], rt0);
1985 1986 1987 1988 1989
		rt0 = NULL;
	}

	/* Update the global pointers */
	net->mpls.platform_labels = limit;
1990
	rcu_assign_pointer(net->mpls.platform_label, labels);
1991 1992 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021 2022 2023 2024 2025 2026 2027 2028 2029 2030 2031 2032 2033

	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;
}

2034 2035 2036
#define MPLS_NS_SYSCTL_OFFSET(field)		\
	(&((struct net *)0)->field)

2037
static const struct ctl_table mpls_table[] = {
2038 2039 2040 2041 2042 2043 2044
	{
		.procname	= "platform_labels",
		.data		= NULL,
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= mpls_platform_labels,
	},
2045 2046 2047 2048 2049 2050 2051 2052 2053
	{
		.procname	= "ip_ttl_propagate",
		.data		= MPLS_NS_SYSCTL_OFFSET(mpls.ip_ttl_propagate),
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec_minmax,
		.extra1		= &zero,
		.extra2		= &one,
	},
2054 2055 2056 2057 2058 2059 2060 2061 2062
	{
		.procname	= "default_ttl",
		.data		= MPLS_NS_SYSCTL_OFFSET(mpls.default_ttl),
		.maxlen		= sizeof(int),
		.mode		= 0644,
		.proc_handler	= proc_dointvec_minmax,
		.extra1		= &one,
		.extra2		= &ttl_max,
	},
2063 2064 2065
	{ }
};

E
Eric W. Biederman 已提交
2066 2067
static int mpls_net_init(struct net *net)
{
2068
	struct ctl_table *table;
2069
	int i;
2070

E
Eric W. Biederman 已提交
2071 2072
	net->mpls.platform_labels = 0;
	net->mpls.platform_label = NULL;
2073
	net->mpls.ip_ttl_propagate = 1;
2074
	net->mpls.default_ttl = 255;
E
Eric W. Biederman 已提交
2075

2076 2077 2078 2079
	table = kmemdup(mpls_table, sizeof(mpls_table), GFP_KERNEL);
	if (table == NULL)
		return -ENOMEM;

2080 2081 2082 2083 2084 2085
	/* 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_table) - 1; i++)
		table[i].data = (char *)net + (uintptr_t)table[i].data;

2086
	net->mpls.ctl = register_net_sysctl(net, "net/mpls", table);
2087 2088
	if (net->mpls.ctl == NULL) {
		kfree(table);
2089
		return -ENOMEM;
2090
	}
2091

E
Eric W. Biederman 已提交
2092 2093 2094 2095 2096
	return 0;
}

static void mpls_net_exit(struct net *net)
{
2097 2098
	struct mpls_route __rcu **platform_label;
	size_t platform_labels;
2099
	struct ctl_table *table;
E
Eric W. Biederman 已提交
2100 2101
	unsigned int index;

2102 2103 2104 2105
	table = net->mpls.ctl->ctl_table_arg;
	unregister_net_sysctl_table(net->mpls.ctl);
	kfree(table);

2106 2107
	/* An rcu grace period has passed since there was a device in
	 * the network namespace (and thus the last in flight packet)
E
Eric W. Biederman 已提交
2108 2109 2110 2111 2112 2113 2114 2115
	 * 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();
2116 2117 2118 2119 2120
	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);
2121
		mpls_notify_route(net, index, rt, NULL, NULL);
E
Eric W. Biederman 已提交
2122 2123 2124 2125
		mpls_rt_free(rt);
	}
	rtnl_unlock();

2126
	kvfree(platform_label);
E
Eric W. Biederman 已提交
2127 2128 2129 2130 2131 2132 2133
}

static struct pernet_operations mpls_net_ops = {
	.init = mpls_net_init,
	.exit = mpls_net_exit,
};

R
Robert Shearman 已提交
2134 2135 2136 2137 2138 2139
static struct rtnl_af_ops mpls_af_ops __read_mostly = {
	.family		   = AF_MPLS,
	.fill_stats_af	   = mpls_fill_stats_af,
	.get_stats_af_size = mpls_get_stats_af_size,
};

E
Eric W. Biederman 已提交
2140 2141 2142 2143 2144 2145 2146 2147 2148 2149 2150 2151 2152 2153 2154 2155
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);

R
Robert Shearman 已提交
2156 2157
	rtnl_af_register(&mpls_af_ops);

2158 2159 2160
	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);
D
David Ahern 已提交
2161 2162
	rtnl_register(PF_MPLS, RTM_GETNETCONF, mpls_netconf_get_devconf,
		      mpls_netconf_dump_devconf, NULL);
E
Eric W. Biederman 已提交
2163 2164 2165 2166 2167 2168 2169 2170 2171 2172 2173 2174
	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)
{
2175
	rtnl_unregister_all(PF_MPLS);
R
Robert Shearman 已提交
2176
	rtnl_af_unregister(&mpls_af_ops);
E
Eric W. Biederman 已提交
2177 2178 2179 2180 2181 2182 2183 2184 2185
	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);