-#include <linux/rculist.h>
-
-#include <net/dsfield.h>
-#include <net/dst.h>
-#include <net/icmp.h>
-#include <net/inet_ecn.h>
-#include <net/ip.h>
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-#include <net/ipv6.h>
-#endif
-#include <net/route.h>
-#include <net/xfrm.h>
-
-#include "checksum.h"
-#include "datapath.h"
-#include "tunnel.h"
-#include "vlan.h"
-#include "vport.h"
-#include "vport-generic.h"
-#include "vport-internal_dev.h"
-
-#ifdef NEED_CACHE_TIMEOUT
-/*
- * On kernels where we can't quickly detect changes in the rest of the system
- * we use an expiration time to invalidate the cache. A shorter expiration
- * reduces the length of time that we may potentially blackhole packets while
- * a longer time increases performance by reducing the frequency that the
- * cache needs to be rebuilt. A variety of factors may cause the cache to be
- * invalidated before the expiration time but this is the maximum. The time
- * is expressed in jiffies.
- */
-#define MAX_CACHE_EXP HZ
-#endif
-
-/*
- * Interval to check for and remove caches that are no longer valid. Caches
- * are checked for validity before they are used for packet encapsulation and
- * old caches are removed at that time. However, if no packets are sent through
- * the tunnel then the cache will never be destroyed. Since it holds
- * references to a number of system objects, the cache will continue to use
- * system resources by not allowing those objects to be destroyed. The cache
- * cleaner is periodically run to free invalid caches. It does not
- * significantly affect system performance. A lower interval will release
- * resources faster but will itself consume resources by requiring more frequent
- * checks. A longer interval may result in messages being printed to the kernel
- * message buffer about unreleased resources. The interval is expressed in
- * jiffies.
- */
-#define CACHE_CLEANER_INTERVAL (5 * HZ)
-
-#define CACHE_DATA_ALIGN 16
-#define PORT_TABLE_SIZE 1024
-
-static struct hlist_head *port_table __read_mostly;
-static int port_table_count;
-
-static void cache_cleaner(struct work_struct *work);
-static DECLARE_DELAYED_WORK(cache_cleaner_wq, cache_cleaner);
-
-/*
- * These are just used as an optimization: they don't require any kind of
- * synchronization because we could have just as easily read the value before
- * the port change happened.
- */
-static unsigned int key_local_remote_ports __read_mostly;
-static unsigned int key_remote_ports __read_mostly;
-static unsigned int key_multicast_ports __read_mostly;
-static unsigned int local_remote_ports __read_mostly;
-static unsigned int remote_ports __read_mostly;
-static unsigned int multicast_ports __read_mostly;
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,36)
-#define rt_dst(rt) (rt->dst)
-#else
-#define rt_dst(rt) (rt->u.dst)
-#endif
-
-#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,1,0)
-static struct hh_cache *rt_hh(struct rtable *rt)
-{
- struct neighbour *neigh = dst_get_neighbour(&rt->dst);
- if (!neigh || !(neigh->nud_state & NUD_CONNECTED) ||
- !neigh->hh.hh_len)
- return NULL;
- return &neigh->hh;
-}
-#else
-#define rt_hh(rt) (rt_dst(rt).hh)
-#endif
-
-static struct vport *tnl_vport_to_vport(const struct tnl_vport *tnl_vport)
-{
- return vport_from_priv(tnl_vport);
-}
-
-/* This is analogous to rtnl_dereference for the tunnel cache. It checks that
- * cache_lock is held, so it is only for update side code.
- */
-static struct tnl_cache *cache_dereference(struct tnl_vport *tnl_vport)
-{
- return rcu_dereference_protected(tnl_vport->cache,
- lockdep_is_held(&tnl_vport->cache_lock));
-}
-
-static void schedule_cache_cleaner(void)
-{
- schedule_delayed_work(&cache_cleaner_wq, CACHE_CLEANER_INTERVAL);
-}
-
-static void free_cache(struct tnl_cache *cache)
-{
- if (!cache)
- return;
-
- flow_put(cache->flow);
- ip_rt_put(cache->rt);
- kfree(cache);
-}
-
-static void free_config_rcu(struct rcu_head *rcu)
-{
- struct tnl_mutable_config *c = container_of(rcu, struct tnl_mutable_config, rcu);
- kfree(c);
-}
-
-static void free_cache_rcu(struct rcu_head *rcu)
-{
- struct tnl_cache *c = container_of(rcu, struct tnl_cache, rcu);
- free_cache(c);
-}
-
-/* Frees the portion of 'mutable' that requires RTNL and thus can't happen
- * within an RCU callback. Fortunately this part doesn't require waiting for
- * an RCU grace period.
- */
-static void free_mutable_rtnl(struct tnl_mutable_config *mutable)
-{
- ASSERT_RTNL();
- if (ipv4_is_multicast(mutable->key.daddr) && mutable->mlink) {
- struct in_device *in_dev;
- in_dev = inetdev_by_index(&init_net, mutable->mlink);
- if (in_dev)
- ip_mc_dec_group(in_dev, mutable->key.daddr);
- }
-}
-
-static void assign_config_rcu(struct vport *vport,
- struct tnl_mutable_config *new_config)
-{
- struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
- struct tnl_mutable_config *old_config;
-
- old_config = rtnl_dereference(tnl_vport->mutable);
- rcu_assign_pointer(tnl_vport->mutable, new_config);
-
- free_mutable_rtnl(old_config);
- call_rcu(&old_config->rcu, free_config_rcu);
-}
-
-static void assign_cache_rcu(struct vport *vport, struct tnl_cache *new_cache)
-{
- struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
- struct tnl_cache *old_cache;
-
- old_cache = cache_dereference(tnl_vport);
- rcu_assign_pointer(tnl_vport->cache, new_cache);
-
- if (old_cache)
- call_rcu(&old_cache->rcu, free_cache_rcu);
-}
-
-static unsigned int *find_port_pool(const struct tnl_mutable_config *mutable)
-{
- bool is_multicast = ipv4_is_multicast(mutable->key.daddr);
-
- if (mutable->flags & TNL_F_IN_KEY_MATCH) {
- if (mutable->key.saddr)
- return &local_remote_ports;
- else if (is_multicast)
- return &multicast_ports;
- else
- return &remote_ports;
- } else {
- if (mutable->key.saddr)
- return &key_local_remote_ports;
- else if (is_multicast)
- return &key_multicast_ports;
- else
- return &key_remote_ports;
- }
-}
-
-static u32 port_hash(const struct port_lookup_key *key)
-{
- return jhash2((u32 *)key, (PORT_KEY_LEN / sizeof(u32)), 0);
-}
-
-static struct hlist_head *find_bucket(u32 hash)
-{
- return &port_table[(hash & (PORT_TABLE_SIZE - 1))];
-}
-
-static void port_table_add_port(struct vport *vport)
-{
- struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
- const struct tnl_mutable_config *mutable;
- u32 hash;
-
- if (port_table_count == 0)
- schedule_cache_cleaner();
-
- mutable = rtnl_dereference(tnl_vport->mutable);
- hash = port_hash(&mutable->key);
- hlist_add_head_rcu(&tnl_vport->hash_node, find_bucket(hash));
- port_table_count++;
-
- (*find_port_pool(rtnl_dereference(tnl_vport->mutable)))++;
-}
-
-static void port_table_move_port(struct vport *vport,
- struct tnl_mutable_config *new_mutable)
-{
- struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
- u32 hash;
-
- hash = port_hash(&new_mutable->key);
- hlist_del_init_rcu(&tnl_vport->hash_node);
- hlist_add_head_rcu(&tnl_vport->hash_node, find_bucket(hash));
-
- (*find_port_pool(rtnl_dereference(tnl_vport->mutable)))--;
- assign_config_rcu(vport, new_mutable);
- (*find_port_pool(rtnl_dereference(tnl_vport->mutable)))++;
-}
-
-static void port_table_remove_port(struct vport *vport)
-{
- struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
-
- hlist_del_init_rcu(&tnl_vport->hash_node);
-
- port_table_count--;
- if (port_table_count == 0)
- cancel_delayed_work_sync(&cache_cleaner_wq);
-
- (*find_port_pool(rtnl_dereference(tnl_vport->mutable)))--;
-}
-
-static struct vport *port_table_lookup(struct port_lookup_key *key,
- const struct tnl_mutable_config **pmutable)
-{
- struct hlist_node *n;
- struct hlist_head *bucket;
- u32 hash = port_hash(key);
- struct tnl_vport *tnl_vport;
-
- bucket = find_bucket(hash);
-
- hlist_for_each_entry_rcu(tnl_vport, n, bucket, hash_node) {
- struct tnl_mutable_config *mutable;
-
- mutable = rcu_dereference_rtnl(tnl_vport->mutable);
- if (!memcmp(&mutable->key, key, PORT_KEY_LEN)) {
- *pmutable = mutable;
- return tnl_vport_to_vport(tnl_vport);
- }
- }
-
- return NULL;
-}
-
-struct vport *tnl_find_port(__be32 saddr, __be32 daddr, __be64 key,
- int tunnel_type,
- const struct tnl_mutable_config **mutable)
-{
- struct port_lookup_key lookup;
- struct vport *vport;
- bool is_multicast = ipv4_is_multicast(saddr);
-
- lookup.saddr = saddr;
- lookup.daddr = daddr;
-
- /* First try for exact match on in_key. */
- lookup.in_key = key;
- lookup.tunnel_type = tunnel_type | TNL_T_KEY_EXACT;
- if (!is_multicast && key_local_remote_ports) {
- vport = port_table_lookup(&lookup, mutable);
- if (vport)
- return vport;
- }
- if (key_remote_ports) {
- lookup.saddr = 0;
- vport = port_table_lookup(&lookup, mutable);
- if (vport)
- return vport;
-
- lookup.saddr = saddr;
- }
-
- /* Then try matches that wildcard in_key. */
- lookup.in_key = 0;
- lookup.tunnel_type = tunnel_type | TNL_T_KEY_MATCH;
- if (!is_multicast && local_remote_ports) {
- vport = port_table_lookup(&lookup, mutable);
- if (vport)
- return vport;
- }
- if (remote_ports) {
- lookup.saddr = 0;
- vport = port_table_lookup(&lookup, mutable);
- if (vport)
- return vport;
- }
-
- if (is_multicast) {
- lookup.saddr = 0;
- lookup.daddr = saddr;
- if (key_multicast_ports) {
- lookup.tunnel_type = tunnel_type | TNL_T_KEY_EXACT;
- lookup.in_key = key;
- vport = port_table_lookup(&lookup, mutable);
- if (vport)
- return vport;
- }
- if (multicast_ports) {
- lookup.tunnel_type = tunnel_type | TNL_T_KEY_MATCH;
- lookup.in_key = 0;
- vport = port_table_lookup(&lookup, mutable);
- if (vport)
- return vport;
- }
- }
-
- return NULL;
-}
-
-static void ecn_decapsulate(struct sk_buff *skb, u8 tos)
-{
- if (unlikely(INET_ECN_is_ce(tos))) {
- __be16 protocol = skb->protocol;
-
- skb_set_network_header(skb, ETH_HLEN);
-
- if (protocol == htons(ETH_P_8021Q)) {
- if (unlikely(!pskb_may_pull(skb, VLAN_ETH_HLEN)))
- return;
-
- protocol = vlan_eth_hdr(skb)->h_vlan_encapsulated_proto;
- skb_set_network_header(skb, VLAN_ETH_HLEN);
- }
-
- if (protocol == htons(ETH_P_IP)) {
- if (unlikely(!pskb_may_pull(skb, skb_network_offset(skb)
- + sizeof(struct iphdr))))
- return;
-
- IP_ECN_set_ce(ip_hdr(skb));
- }
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
- else if (protocol == htons(ETH_P_IPV6)) {
- if (unlikely(!pskb_may_pull(skb, skb_network_offset(skb)
- + sizeof(struct ipv6hdr))))
- return;
-
- IP6_ECN_set_ce(ipv6_hdr(skb));
- }
-#endif
- }
-}
-
-/**
- * tnl_rcv - ingress point for generic tunnel code
- *
- * @vport: port this packet was received on
- * @skb: received packet
- * @tos: ToS from encapsulating IP packet, used to copy ECN bits
- *
- * Must be called with rcu_read_lock.
- *
- * Packets received by this function are in the following state:
- * - skb->data points to the inner Ethernet header.
- * - The inner Ethernet header is in the linear data area.
- * - skb->csum does not include the inner Ethernet header.
- * - The layer pointers are undefined.
- */
-void tnl_rcv(struct vport *vport, struct sk_buff *skb, u8 tos)
-{
- struct ethhdr *eh;
-
- skb_reset_mac_header(skb);
- eh = eth_hdr(skb);
-
- if (likely(ntohs(eh->h_proto) >= 1536))
- skb->protocol = eh->h_proto;
- else
- skb->protocol = htons(ETH_P_802_2);
-
- skb_dst_drop(skb);
- nf_reset(skb);
- skb_clear_rxhash(skb);
- secpath_reset(skb);
-
- ecn_decapsulate(skb, tos);
- vlan_set_tci(skb, 0);
-
- if (unlikely(compute_ip_summed(skb, false))) {
- kfree_skb(skb);
- return;
- }
-
- vport_receive(vport, skb);
-}
-
-static bool check_ipv4_address(__be32 addr)
-{
- if (ipv4_is_multicast(addr) || ipv4_is_lbcast(addr)
- || ipv4_is_loopback(addr) || ipv4_is_zeronet(addr))
- return false;
-
- return true;
-}
-
-static bool ipv4_should_icmp(struct sk_buff *skb)
-{
- struct iphdr *old_iph = ip_hdr(skb);
-
- /* Don't respond to L2 broadcast. */
- if (is_multicast_ether_addr(eth_hdr(skb)->h_dest))
- return false;
-
- /* Don't respond to L3 broadcast or invalid addresses. */
- if (!check_ipv4_address(old_iph->daddr) ||
- !check_ipv4_address(old_iph->saddr))
- return false;
-
- /* Only respond to the first fragment. */
- if (old_iph->frag_off & htons(IP_OFFSET))
- return false;
-
- /* Don't respond to ICMP error messages. */
- if (old_iph->protocol == IPPROTO_ICMP) {
- u8 icmp_type, *icmp_typep;
-
- icmp_typep = skb_header_pointer(skb, (u8 *)old_iph +
- (old_iph->ihl << 2) +
- offsetof(struct icmphdr, type) -
- skb->data, sizeof(icmp_type),
- &icmp_type);
-
- if (!icmp_typep)
- return false;
-
- if (*icmp_typep > NR_ICMP_TYPES
- || (*icmp_typep <= ICMP_PARAMETERPROB
- && *icmp_typep != ICMP_ECHOREPLY
- && *icmp_typep != ICMP_ECHO))
- return false;
- }
-
- return true;
-}
-
-static void ipv4_build_icmp(struct sk_buff *skb, struct sk_buff *nskb,
- unsigned int mtu, unsigned int payload_length)
-{
- struct iphdr *iph, *old_iph = ip_hdr(skb);
- struct icmphdr *icmph;
- u8 *payload;
-
- iph = (struct iphdr *)skb_put(nskb, sizeof(struct iphdr));
- icmph = (struct icmphdr *)skb_put(nskb, sizeof(struct icmphdr));
- payload = skb_put(nskb, payload_length);
-
- /* IP */
- iph->version = 4;
- iph->ihl = sizeof(struct iphdr) >> 2;
- iph->tos = (old_iph->tos & IPTOS_TOS_MASK) |
- IPTOS_PREC_INTERNETCONTROL;
- iph->tot_len = htons(sizeof(struct iphdr)
- + sizeof(struct icmphdr)
- + payload_length);
- get_random_bytes(&iph->id, sizeof(iph->id));
- iph->frag_off = 0;
- iph->ttl = IPDEFTTL;
- iph->protocol = IPPROTO_ICMP;
- iph->daddr = old_iph->saddr;
- iph->saddr = old_iph->daddr;
-
- ip_send_check(iph);
-
- /* ICMP */
- icmph->type = ICMP_DEST_UNREACH;
- icmph->code = ICMP_FRAG_NEEDED;
- icmph->un.gateway = htonl(mtu);
- icmph->checksum = 0;
-
- nskb->csum = csum_partial((u8 *)icmph, sizeof(struct icmphdr), 0);
- nskb->csum = skb_copy_and_csum_bits(skb, (u8 *)old_iph - skb->data,
- payload, payload_length,
- nskb->csum);
- icmph->checksum = csum_fold(nskb->csum);
-}
-
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
-static bool ipv6_should_icmp(struct sk_buff *skb)
-{
- struct ipv6hdr *old_ipv6h = ipv6_hdr(skb);
- int addr_type;
- int payload_off = (u8 *)(old_ipv6h + 1) - skb->data;
- u8 nexthdr = ipv6_hdr(skb)->nexthdr;
-
- /* Check source address is valid. */
- addr_type = ipv6_addr_type(&old_ipv6h->saddr);
- if (addr_type & IPV6_ADDR_MULTICAST || addr_type == IPV6_ADDR_ANY)
- return false;
-
- /* Don't reply to unspecified addresses. */
- if (ipv6_addr_type(&old_ipv6h->daddr) == IPV6_ADDR_ANY)
- return false;
-
- /* Don't respond to ICMP error messages. */
- payload_off = ipv6_skip_exthdr(skb, payload_off, &nexthdr);
- if (payload_off < 0)
- return false;
-
- if (nexthdr == NEXTHDR_ICMP) {
- u8 icmp_type, *icmp_typep;
-
- icmp_typep = skb_header_pointer(skb, payload_off +
- offsetof(struct icmp6hdr,
- icmp6_type),
- sizeof(icmp_type), &icmp_type);
-
- if (!icmp_typep || !(*icmp_typep & ICMPV6_INFOMSG_MASK))
- return false;
- }
-
- return true;
-}
-
-static void ipv6_build_icmp(struct sk_buff *skb, struct sk_buff *nskb,
- unsigned int mtu, unsigned int payload_length)
-{
- struct ipv6hdr *ipv6h, *old_ipv6h = ipv6_hdr(skb);
- struct icmp6hdr *icmp6h;
- u8 *payload;
-
- ipv6h = (struct ipv6hdr *)skb_put(nskb, sizeof(struct ipv6hdr));
- icmp6h = (struct icmp6hdr *)skb_put(nskb, sizeof(struct icmp6hdr));
- payload = skb_put(nskb, payload_length);
-
- /* IPv6 */
- ipv6h->version = 6;
- ipv6h->priority = 0;
- memset(&ipv6h->flow_lbl, 0, sizeof(ipv6h->flow_lbl));
- ipv6h->payload_len = htons(sizeof(struct icmp6hdr)
- + payload_length);
- ipv6h->nexthdr = NEXTHDR_ICMP;
- ipv6h->hop_limit = IPV6_DEFAULT_HOPLIMIT;
- ipv6_addr_copy(&ipv6h->daddr, &old_ipv6h->saddr);
- ipv6_addr_copy(&ipv6h->saddr, &old_ipv6h->daddr);
-
- /* ICMPv6 */
- icmp6h->icmp6_type = ICMPV6_PKT_TOOBIG;
- icmp6h->icmp6_code = 0;
- icmp6h->icmp6_cksum = 0;
- icmp6h->icmp6_mtu = htonl(mtu);
-
- nskb->csum = csum_partial((u8 *)icmp6h, sizeof(struct icmp6hdr), 0);
- nskb->csum = skb_copy_and_csum_bits(skb, (u8 *)old_ipv6h - skb->data,
- payload, payload_length,
- nskb->csum);
- icmp6h->icmp6_cksum = csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr,
- sizeof(struct icmp6hdr)
- + payload_length,
- ipv6h->nexthdr, nskb->csum);
-}
-#endif /* IPv6 */
-
-bool tnl_frag_needed(struct vport *vport,
- const struct tnl_mutable_config *mutable,
- struct sk_buff *skb, unsigned int mtu, __be64 flow_key)
-{
- unsigned int eth_hdr_len = ETH_HLEN;
- unsigned int total_length = 0, header_length = 0, payload_length;
- struct ethhdr *eh, *old_eh = eth_hdr(skb);
- struct sk_buff *nskb;
-
- /* Sanity check */
- if (skb->protocol == htons(ETH_P_IP)) {
- if (mtu < IP_MIN_MTU)
- return false;
-
- if (!ipv4_should_icmp(skb))
- return true;
- }
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
- else if (skb->protocol == htons(ETH_P_IPV6)) {
- if (mtu < IPV6_MIN_MTU)
- return false;
-
- /*
- * In theory we should do PMTUD on IPv6 multicast messages but
- * we don't have an address to send from so just fragment.
- */
- if (ipv6_addr_type(&ipv6_hdr(skb)->daddr) & IPV6_ADDR_MULTICAST)
- return false;
-
- if (!ipv6_should_icmp(skb))
- return true;
- }
-#endif
- else
- return false;
-
- /* Allocate */
- if (old_eh->h_proto == htons(ETH_P_8021Q))
- eth_hdr_len = VLAN_ETH_HLEN;
-
- payload_length = skb->len - eth_hdr_len;
- if (skb->protocol == htons(ETH_P_IP)) {
- header_length = sizeof(struct iphdr) + sizeof(struct icmphdr);
- total_length = min_t(unsigned int, header_length +
- payload_length, 576);
- }
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
- else {
- header_length = sizeof(struct ipv6hdr) +
- sizeof(struct icmp6hdr);
- total_length = min_t(unsigned int, header_length +
- payload_length, IPV6_MIN_MTU);
- }
-#endif
-
- payload_length = total_length - header_length;
-
- nskb = dev_alloc_skb(NET_IP_ALIGN + eth_hdr_len + header_length +
- payload_length);
- if (!nskb)
- return false;
-
- skb_reserve(nskb, NET_IP_ALIGN);
-
- /* Ethernet / VLAN */
- eh = (struct ethhdr *)skb_put(nskb, eth_hdr_len);
- memcpy(eh->h_dest, old_eh->h_source, ETH_ALEN);
- memcpy(eh->h_source, mutable->eth_addr, ETH_ALEN);
- nskb->protocol = eh->h_proto = old_eh->h_proto;
- if (old_eh->h_proto == htons(ETH_P_8021Q)) {
- struct vlan_ethhdr *vh = (struct vlan_ethhdr *)eh;
-
- vh->h_vlan_TCI = vlan_eth_hdr(skb)->h_vlan_TCI;
- vh->h_vlan_encapsulated_proto = skb->protocol;
- } else
- vlan_set_tci(nskb, vlan_get_tci(skb));
- skb_reset_mac_header(nskb);
-
- /* Protocol */
- if (skb->protocol == htons(ETH_P_IP))
- ipv4_build_icmp(skb, nskb, mtu, payload_length);
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
- else
- ipv6_build_icmp(skb, nskb, mtu, payload_length);
-#endif
-
- /*
- * Assume that flow based keys are symmetric with respect to input
- * and output and use the key that we were going to put on the
- * outgoing packet for the fake received packet. If the keys are
- * not symmetric then PMTUD needs to be disabled since we won't have
- * any way of synthesizing packets.
- */
- if ((mutable->flags & (TNL_F_IN_KEY_MATCH | TNL_F_OUT_KEY_ACTION)) ==
- (TNL_F_IN_KEY_MATCH | TNL_F_OUT_KEY_ACTION))
- OVS_CB(nskb)->tun_id = flow_key;
-
- if (unlikely(compute_ip_summed(nskb, false))) {
- kfree_skb(nskb);
- return false;
- }
-
- vport_receive(vport, nskb);
-
- return true;
-}
-
-static bool check_mtu(struct sk_buff *skb,
- struct vport *vport,
- const struct tnl_mutable_config *mutable,
- const struct rtable *rt, __be16 *frag_offp)
-{
- bool df_inherit = mutable->flags & TNL_F_DF_INHERIT;
- bool pmtud = mutable->flags & TNL_F_PMTUD;
- __be16 frag_off = mutable->flags & TNL_F_DF_DEFAULT ? htons(IP_DF) : 0;
- int mtu = 0;
- unsigned int packet_length = skb->len - ETH_HLEN;
-
- /* Allow for one level of tagging in the packet length. */
- if (!vlan_tx_tag_present(skb) &&
- eth_hdr(skb)->h_proto == htons(ETH_P_8021Q))
- packet_length -= VLAN_HLEN;
-
- if (pmtud) {
- int vlan_header = 0;
-
- /* The tag needs to go in packet regardless of where it
- * currently is, so subtract it from the MTU.
- */
- if (vlan_tx_tag_present(skb) ||
- eth_hdr(skb)->h_proto == htons(ETH_P_8021Q))
- vlan_header = VLAN_HLEN;
-
- mtu = dst_mtu(&rt_dst(rt))
- - ETH_HLEN
- - mutable->tunnel_hlen
- - vlan_header;
- }
-
- if (skb->protocol == htons(ETH_P_IP)) {
- struct iphdr *iph = ip_hdr(skb);
-
- if (df_inherit)
- frag_off = iph->frag_off & htons(IP_DF);
-
- if (pmtud && iph->frag_off & htons(IP_DF)) {
- mtu = max(mtu, IP_MIN_MTU);
-
- if (packet_length > mtu &&
- tnl_frag_needed(vport, mutable, skb, mtu,
- OVS_CB(skb)->tun_id))
- return false;
- }
- }
-#if defined(CONFIG_IPV6) || defined(CONFIG_IPV6_MODULE)
- else if (skb->protocol == htons(ETH_P_IPV6)) {
- /* IPv6 requires end hosts to do fragmentation
- * if the packet is above the minimum MTU.
- */
- if (df_inherit && packet_length > IPV6_MIN_MTU)
- frag_off = htons(IP_DF);
-
- if (pmtud) {
- mtu = max(mtu, IPV6_MIN_MTU);
-
- if (packet_length > mtu &&
- tnl_frag_needed(vport, mutable, skb, mtu,
- OVS_CB(skb)->tun_id))
- return false;
- }
- }
-#endif
-
- *frag_offp = frag_off;
- return true;
-}
-
-static void create_tunnel_header(const struct vport *vport,
- const struct tnl_mutable_config *mutable,
- const struct rtable *rt, void *header)
-{
- struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
- struct iphdr *iph = header;
-
- iph->version = 4;
- iph->ihl = sizeof(struct iphdr) >> 2;
- iph->frag_off = htons(IP_DF);
- iph->protocol = tnl_vport->tnl_ops->ipproto;
- iph->tos = mutable->tos;
- iph->daddr = rt->rt_dst;
- iph->saddr = rt->rt_src;
- iph->ttl = mutable->ttl;
- if (!iph->ttl)
- iph->ttl = ip4_dst_hoplimit(&rt_dst(rt));
-
- tnl_vport->tnl_ops->build_header(vport, mutable, iph + 1);
-}
-
-static void *get_cached_header(const struct tnl_cache *cache)
-{
- return (void *)cache + ALIGN(sizeof(struct tnl_cache), CACHE_DATA_ALIGN);
-}
-
-static bool check_cache_valid(const struct tnl_cache *cache,
- const struct tnl_mutable_config *mutable)
-{
- struct hh_cache *hh;
-
- if (!cache)
- return false;
-
- hh = rt_hh(cache->rt);
- return hh &&
-#ifdef NEED_CACHE_TIMEOUT
- time_before(jiffies, cache->expiration) &&
-#endif
-#ifdef HAVE_RT_GENID
- atomic_read(&init_net.ipv4.rt_genid) == cache->rt->rt_genid &&
-#endif
-#ifdef HAVE_HH_SEQ
- hh->hh_lock.sequence == cache->hh_seq &&
-#endif
- mutable->seq == cache->mutable_seq &&
- (!is_internal_dev(rt_dst(cache->rt).dev) ||
- (cache->flow && !cache->flow->dead));
-}
-
-static void __cache_cleaner(struct tnl_vport *tnl_vport)
-{
- const struct tnl_mutable_config *mutable =
- rcu_dereference(tnl_vport->mutable);
- const struct tnl_cache *cache = rcu_dereference(tnl_vport->cache);
-
- if (cache && !check_cache_valid(cache, mutable) &&
- spin_trylock_bh(&tnl_vport->cache_lock)) {
- assign_cache_rcu(tnl_vport_to_vport(tnl_vport), NULL);
- spin_unlock_bh(&tnl_vport->cache_lock);
- }
-}
-
-static void cache_cleaner(struct work_struct *work)
-{
- int i;
-
- schedule_cache_cleaner();
-
- rcu_read_lock();
- for (i = 0; i < PORT_TABLE_SIZE; i++) {
- struct hlist_node *n;
- struct hlist_head *bucket;
- struct tnl_vport *tnl_vport;
-
- bucket = &port_table[i];
- hlist_for_each_entry_rcu(tnl_vport, n, bucket, hash_node)
- __cache_cleaner(tnl_vport);
- }
- rcu_read_unlock();
-}
-
-static void create_eth_hdr(struct tnl_cache *cache, struct hh_cache *hh)
-{
- void *cache_data = get_cached_header(cache);
- int hh_off;
-
-#ifdef HAVE_HH_SEQ
- unsigned hh_seq;
-
- do {
- hh_seq = read_seqbegin(&hh->hh_lock);
- hh_off = HH_DATA_ALIGN(hh->hh_len) - hh->hh_len;
- memcpy(cache_data, (void *)hh->hh_data + hh_off, hh->hh_len);
- cache->hh_len = hh->hh_len;
- } while (read_seqretry(&hh->hh_lock, hh_seq));
-
- cache->hh_seq = hh_seq;
-#else
- read_lock(&hh->hh_lock);
- hh_off = HH_DATA_ALIGN(hh->hh_len) - hh->hh_len;
- memcpy(cache_data, (void *)hh->hh_data + hh_off, hh->hh_len);
- cache->hh_len = hh->hh_len;
- read_unlock(&hh->hh_lock);
-#endif
-}
-
-static struct tnl_cache *build_cache(struct vport *vport,
- const struct tnl_mutable_config *mutable,
- struct rtable *rt)
-{
- struct tnl_vport *tnl_vport = tnl_vport_priv(vport);
- struct tnl_cache *cache;
- void *cache_data;
- int cache_len;
- struct hh_cache *hh;
-
- if (!(mutable->flags & TNL_F_HDR_CACHE))
- return NULL;
-
- /*
- * If there is no entry in the ARP cache or if this device does not
- * support hard header caching just fall back to the IP stack.
- */
-
- hh = rt_hh(rt);
- if (!hh)
- return NULL;
-
- /*
- * If lock is contended fall back to directly building the header.
- * We're not going to help performance by sitting here spinning.
- */
- if (!spin_trylock(&tnl_vport->cache_lock))
- return NULL;
-
- cache = cache_dereference(tnl_vport);
- if (check_cache_valid(cache, mutable))
- goto unlock;
- else
- cache = NULL;
-
- cache_len = LL_RESERVED_SPACE(rt_dst(rt).dev) + mutable->tunnel_hlen;
-
- cache = kzalloc(ALIGN(sizeof(struct tnl_cache), CACHE_DATA_ALIGN) +
- cache_len, GFP_ATOMIC);
- if (!cache)
- goto unlock;
-
- create_eth_hdr(cache, hh);
- cache_data = get_cached_header(cache) + cache->hh_len;
- cache->len = cache->hh_len + mutable->tunnel_hlen;
-
- create_tunnel_header(vport, mutable, rt, cache_data);
-
- cache->mutable_seq = mutable->seq;
- cache->rt = rt;
-#ifdef NEED_CACHE_TIMEOUT
- cache->expiration = jiffies + tnl_vport->cache_exp_interval;
-#endif
-
- if (is_internal_dev(rt_dst(rt).dev)) {
- struct sw_flow_key flow_key;
- struct vport *dst_vport;
- struct sk_buff *skb;
- int err;
- int flow_key_len;
- struct sw_flow *flow;