mirror of https://gitee.com/openkylin/linux.git
1750 lines
39 KiB
C
1750 lines
39 KiB
C
#include <linux/types.h>
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#include <linux/skbuff.h>
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#include <linux/socket.h>
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#include <linux/sysctl.h>
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#include <linux/net.h>
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#include <linux/module.h>
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#include <linux/if_arp.h>
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#include <linux/ipv6.h>
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#include <linux/mpls.h>
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#include <linux/vmalloc.h>
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#include <net/ip.h>
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#include <net/dst.h>
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#include <net/sock.h>
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#include <net/arp.h>
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#include <net/ip_fib.h>
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#include <net/netevent.h>
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#include <net/netns/generic.h>
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#if IS_ENABLED(CONFIG_IPV6)
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#include <net/ipv6.h>
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#include <net/addrconf.h>
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#endif
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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
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* a multipath route
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*/
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#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 label_limit = (1 << 20) - 1;
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static void rtmsg_lfib(int event, u32 label, struct mpls_route *rt,
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struct nlmsghdr *nlh, struct net *net, u32 portid,
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unsigned int nlm_flags);
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static struct mpls_route *mpls_route_input_rcu(struct net *net, unsigned index)
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{
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struct mpls_route *rt = NULL;
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if (index < net->mpls.platform_labels) {
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struct mpls_route __rcu **platform_label =
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rcu_dereference(net->mpls.platform_label);
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rt = rcu_dereference(platform_label[index]);
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}
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return rt;
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}
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static inline struct mpls_dev *mpls_dev_get(const struct net_device *dev)
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{
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return rcu_dereference_rtnl(dev->mpls_ptr);
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}
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bool mpls_output_possible(const struct net_device *dev)
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{
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return dev && (dev->flags & IFF_UP) && netif_carrier_ok(dev);
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}
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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)
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{
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u8 *nh0_via = PTR_ALIGN((u8 *)&rt->rt_nh[rt->rt_nhn], VIA_ALEN_ALIGN);
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int nh_index = nh - rt->rt_nh;
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return nh0_via + rt->rt_max_alen * nh_index;
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}
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static const u8 *mpls_nh_via(const struct mpls_route *rt,
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const struct mpls_nh *nh)
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{
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return __mpls_nh_via((struct mpls_route *)rt, (struct mpls_nh *)nh);
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}
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static unsigned int mpls_nh_header_size(const struct mpls_nh *nh)
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{
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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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{
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/* The amount of data the layer 2 frame can hold */
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return dev->mtu;
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}
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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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{
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if (skb->len <= mtu)
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return false;
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if (skb_is_gso(skb) && skb_gso_validate_mtu(skb, mtu))
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return false;
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return true;
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}
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EXPORT_SYMBOL_GPL(mpls_pkt_too_big);
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static u32 mpls_multipath_hash(struct mpls_route *rt,
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struct sk_buff *skb, bool bos)
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{
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struct mpls_entry_decoded dec;
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struct mpls_shim_hdr *hdr;
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bool eli_seen = false;
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int label_index;
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u32 hash = 0;
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for (label_index = 0; label_index < MAX_MP_SELECT_LABELS && !bos;
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label_index++) {
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if (!pskb_may_pull(skb, sizeof(*hdr) * label_index))
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break;
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/* Read and decode the current label */
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hdr = mpls_hdr(skb) + label_index;
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dec = mpls_entry_decode(hdr);
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/* RFC6790 - reserved labels MUST NOT be used as keys
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* for the load-balancing function
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*/
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if (likely(dec.label >= MPLS_LABEL_FIRST_UNRESERVED)) {
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hash = jhash_1word(dec.label, hash);
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/* The entropy label follows the entropy label
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* indicator, so this means that the entropy
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* label was just added to the hash - no need to
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* go any deeper either in the label stack or in the
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* payload
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*/
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if (eli_seen)
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break;
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} else if (dec.label == MPLS_LABEL_ENTROPY) {
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eli_seen = true;
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}
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bos = dec.bos;
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if (bos && pskb_may_pull(skb, sizeof(*hdr) * label_index +
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sizeof(struct iphdr))) {
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const struct iphdr *v4hdr;
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v4hdr = (const struct iphdr *)(mpls_hdr(skb) +
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label_index);
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if (v4hdr->version == 4) {
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hash = jhash_3words(ntohl(v4hdr->saddr),
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ntohl(v4hdr->daddr),
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v4hdr->protocol, hash);
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} else if (v4hdr->version == 6 &&
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pskb_may_pull(skb, sizeof(*hdr) * label_index +
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sizeof(struct ipv6hdr))) {
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const struct ipv6hdr *v6hdr;
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v6hdr = (const struct ipv6hdr *)(mpls_hdr(skb) +
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label_index);
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hash = __ipv6_addr_jhash(&v6hdr->saddr, hash);
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hash = __ipv6_addr_jhash(&v6hdr->daddr, hash);
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hash = jhash_1word(v6hdr->nexthdr, hash);
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}
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}
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}
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return hash;
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}
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static struct mpls_nh *mpls_select_multipath(struct mpls_route *rt,
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struct sk_buff *skb, bool bos)
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{
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int alive = ACCESS_ONCE(rt->rt_nhn_alive);
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u32 hash = 0;
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int nh_index = 0;
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int n = 0;
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/* No need to look further into packet if there's only
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* one path
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*/
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if (rt->rt_nhn == 1)
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goto out;
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if (alive <= 0)
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return NULL;
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hash = mpls_multipath_hash(rt, skb, bos);
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nh_index = hash % alive;
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if (alive == rt->rt_nhn)
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goto out;
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for_nexthops(rt) {
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if (nh->nh_flags & (RTNH_F_DEAD | RTNH_F_LINKDOWN))
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continue;
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if (n == nh_index)
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return nh;
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n++;
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} endfor_nexthops(rt);
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out:
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return &rt->rt_nh[nh_index];
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}
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static bool mpls_egress(struct mpls_route *rt, struct sk_buff *skb,
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struct mpls_entry_decoded dec)
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{
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enum mpls_payload_type payload_type;
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bool success = false;
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/* The IPv4 code below accesses through the IPv4 header
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* checksum, which is 12 bytes into the packet.
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* The IPv6 code below accesses through the IPv6 hop limit
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* which is 8 bytes into the packet.
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*
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* For all supported cases there should always be at least 12
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* bytes of packet data present. The IPv4 header is 20 bytes
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* without options and the IPv6 header is always 40 bytes
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* long.
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*/
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if (!pskb_may_pull(skb, 12))
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return false;
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payload_type = rt->rt_payload_type;
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if (payload_type == MPT_UNSPEC)
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payload_type = ip_hdr(skb)->version;
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switch (payload_type) {
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case MPT_IPV4: {
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struct iphdr *hdr4 = ip_hdr(skb);
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skb->protocol = htons(ETH_P_IP);
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csum_replace2(&hdr4->check,
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htons(hdr4->ttl << 8),
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htons(dec.ttl << 8));
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hdr4->ttl = dec.ttl;
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success = true;
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break;
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}
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case MPT_IPV6: {
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struct ipv6hdr *hdr6 = ipv6_hdr(skb);
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skb->protocol = htons(ETH_P_IPV6);
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hdr6->hop_limit = dec.ttl;
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success = true;
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break;
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}
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case MPT_UNSPEC:
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break;
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}
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return success;
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}
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static int mpls_forward(struct sk_buff *skb, struct net_device *dev,
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struct packet_type *pt, struct net_device *orig_dev)
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{
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struct net *net = dev_net(dev);
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struct mpls_shim_hdr *hdr;
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struct mpls_route *rt;
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struct mpls_nh *nh;
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struct mpls_entry_decoded dec;
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struct net_device *out_dev;
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struct mpls_dev *mdev;
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unsigned int hh_len;
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unsigned int new_header_size;
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unsigned int mtu;
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int err;
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/* 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 || !mdev->input_enabled)
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goto drop;
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if (skb->pkt_type != PACKET_HOST)
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goto drop;
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if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
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goto drop;
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if (!pskb_may_pull(skb, sizeof(*hdr)))
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goto drop;
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/* Read and decode the label */
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hdr = mpls_hdr(skb);
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dec = mpls_entry_decode(hdr);
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/* Pop the label */
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skb_pull(skb, sizeof(*hdr));
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skb_reset_network_header(skb);
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skb_orphan(skb);
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rt = mpls_route_input_rcu(net, dec.label);
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if (!rt)
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goto drop;
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nh = mpls_select_multipath(rt, skb, dec.bos);
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if (!nh)
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goto drop;
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/* Find the output device */
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out_dev = rcu_dereference(nh->nh_dev);
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if (!mpls_output_possible(out_dev))
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goto drop;
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if (skb_warn_if_lro(skb))
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goto drop;
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skb_forward_csum(skb);
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/* Verify ttl is valid */
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if (dec.ttl <= 1)
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goto drop;
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dec.ttl -= 1;
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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);
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if (mpls_pkt_too_big(skb, mtu - new_header_size))
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goto drop;
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hh_len = LL_RESERVED_SPACE(out_dev);
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if (!out_dev->header_ops)
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hh_len = 0;
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/* Ensure there is enough space for the headers in the skb */
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if (skb_cow(skb, hh_len + new_header_size))
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goto drop;
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skb->dev = out_dev;
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skb->protocol = htons(ETH_P_MPLS_UC);
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if (unlikely(!new_header_size && dec.bos)) {
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/* Penultimate hop popping */
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if (!mpls_egress(rt, skb, dec))
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goto drop;
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} else {
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bool bos;
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int i;
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skb_push(skb, new_header_size);
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skb_reset_network_header(skb);
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/* Push the new labels */
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hdr = mpls_hdr(skb);
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bos = dec.bos;
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for (i = nh->nh_labels - 1; i >= 0; i--) {
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hdr[i] = mpls_entry_encode(nh->nh_label[i],
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dec.ttl, 0, bos);
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bos = false;
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}
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}
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/* If via wasn't specified then send out using device address */
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if (nh->nh_via_table == MPLS_NEIGH_TABLE_UNSPEC)
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err = neigh_xmit(NEIGH_LINK_TABLE, out_dev,
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out_dev->dev_addr, skb);
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else
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err = neigh_xmit(nh->nh_via_table, out_dev,
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mpls_nh_via(rt, nh), skb);
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if (err)
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net_dbg_ratelimited("%s: packet transmission failed: %d\n",
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__func__, err);
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return 0;
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drop:
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kfree_skb(skb);
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return NET_RX_DROP;
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}
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static struct packet_type mpls_packet_type __read_mostly = {
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.type = cpu_to_be16(ETH_P_MPLS_UC),
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.func = mpls_forward,
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};
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static const struct nla_policy rtm_mpls_policy[RTA_MAX+1] = {
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[RTA_DST] = { .type = NLA_U32 },
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[RTA_OIF] = { .type = NLA_U32 },
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};
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struct mpls_route_config {
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u32 rc_protocol;
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u32 rc_ifindex;
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u8 rc_via_table;
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u8 rc_via_alen;
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u8 rc_via[MAX_VIA_ALEN];
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u32 rc_label;
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u8 rc_output_labels;
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u32 rc_output_label[MAX_NEW_LABELS];
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u32 rc_nlflags;
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enum mpls_payload_type rc_payload_type;
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struct nl_info rc_nlinfo;
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struct rtnexthop *rc_mp;
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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),
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VIA_ALEN_ALIGN) +
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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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}
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return rt;
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}
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static void mpls_rt_free(struct mpls_route *rt)
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{
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if (rt)
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kfree_rcu(rt, rt_rcu);
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}
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static void mpls_notify_route(struct net *net, unsigned index,
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struct mpls_route *old, struct mpls_route *new,
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const struct nl_info *info)
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{
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struct nlmsghdr *nlh = info ? info->nlh : NULL;
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unsigned portid = info ? info->portid : 0;
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int event = new ? RTM_NEWROUTE : RTM_DELROUTE;
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struct mpls_route *rt = new ? new : old;
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unsigned nlm_flags = (old && new) ? NLM_F_REPLACE : 0;
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/* 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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}
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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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{
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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);
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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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|
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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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|
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static unsigned find_free_label(struct net *net)
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{
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struct mpls_route __rcu **platform_label;
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size_t platform_labels;
|
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unsigned index;
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|
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platform_label = rtnl_dereference(net->mpls.platform_label);
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platform_labels = net->mpls.platform_labels;
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for (index = MPLS_LABEL_FIRST_UNRESERVED; index < platform_labels;
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index++) {
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if (!rtnl_dereference(platform_label[index]))
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return index;
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}
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return LABEL_NOT_SPECIFIED;
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}
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|
|
#if IS_ENABLED(CONFIG_INET)
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static struct net_device *inet_fib_lookup_dev(struct net *net,
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const void *addr)
|
|
{
|
|
struct net_device *dev;
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struct rtable *rt;
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struct in_addr daddr;
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memcpy(&daddr, addr, sizeof(struct in_addr));
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rt = ip_route_output(net, daddr.s_addr, 0, 0, 0);
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if (IS_ERR(rt))
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return ERR_CAST(rt);
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dev = rt->dst.dev;
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dev_hold(dev);
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ip_rt_put(rt);
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return dev;
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}
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#else
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static struct net_device *inet_fib_lookup_dev(struct net *net,
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const void *addr)
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{
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return ERR_PTR(-EAFNOSUPPORT);
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}
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#endif
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|
|
#if IS_ENABLED(CONFIG_IPV6)
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static struct net_device *inet6_fib_lookup_dev(struct net *net,
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const void *addr)
|
|
{
|
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struct net_device *dev;
|
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struct dst_entry *dst;
|
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struct flowi6 fl6;
|
|
int err;
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|
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if (!ipv6_stub)
|
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return ERR_PTR(-EAFNOSUPPORT);
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|
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memset(&fl6, 0, sizeof(fl6));
|
|
memcpy(&fl6.daddr, addr, sizeof(struct in6_addr));
|
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err = ipv6_stub->ipv6_dst_lookup(net, NULL, &dst, &fl6);
|
|
if (err)
|
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return ERR_PTR(err);
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|
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dev = dst->dev;
|
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dev_hold(dev);
|
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dst_release(dst);
|
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|
|
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 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);
|
|
}
|
|
|
|
/* Reserved labels may not be set */
|
|
if (index < MPLS_LABEL_FIRST_UNRESERVED)
|
|
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 */
|
|
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;
|
|
|
|
/* Reserved labels may not be removed */
|
|
if (index < MPLS_LABEL_FIRST_UNRESERVED)
|
|
goto errout;
|
|
|
|
/* The full 20 bit range may not be supported */
|
|
if (index >= net->mpls.platform_labels)
|
|
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 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;
|
|
|
|
change_nexthops(rt) {
|
|
if (rtnl_dereference(nh->nh_dev) != dev)
|
|
continue;
|
|
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;
|
|
ACCESS_ONCE(rt->rt_nhn_alive) = rt->rt_nhn_alive - 1;
|
|
break;
|
|
}
|
|
if (event == NETDEV_UNREGISTER)
|
|
RCU_INIT_POINTER(nh->nh_dev, NULL);
|
|
} endfor_nexthops(rt);
|
|
}
|
|
}
|
|
|
|
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;
|
|
|
|
/* Reserved labels may not be set */
|
|
if (cfg->rc_label < MPLS_LABEL_FIRST_UNRESERVED)
|
|
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_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);
|