Merge branch 'next' into for-linus

1 files changed, 1345 insertions, 0 deletions

diff --git a/net/openvswitch/flow.c b/net/openvswitch/flow.c
new file mode 100644
index 000000000000..1252c3081ef1
--- /dev/null
+++ b/net/openvswitch/flow.c
@@ -0,0 +1,1345 @@
+/*
+ * Copyright (c) 2007-2011 Nicira Networks.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of version 2 of the GNU General Public
+ * License as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA
+ */
+
+#include "flow.h"
+#include "datapath.h"
+#include <linux/uaccess.h>
+#include <linux/netdevice.h>
+#include <linux/etherdevice.h>
+#include <linux/if_ether.h>
+#include <linux/if_vlan.h>
+#include <net/llc_pdu.h>
+#include <linux/kernel.h>
+#include <linux/jhash.h>
+#include <linux/jiffies.h>
+#include <linux/llc.h>
+#include <linux/module.h>
+#include <linux/in.h>
+#include <linux/rcupdate.h>
+#include <linux/if_arp.h>
+#include <linux/ip.h>
+#include <linux/ipv6.h>
+#include <linux/tcp.h>
+#include <linux/udp.h>
+#include <linux/icmp.h>
+#include <linux/icmpv6.h>
+#include <linux/rculist.h>
+#include <net/ip.h>
+#include <net/ipv6.h>
+#include <net/ndisc.h>
+
+static struct kmem_cache *flow_cache;
+
+static int check_header(struct sk_buff *skb, int len)
+{
+        if (unlikely(skb->len < len))
+                return -EINVAL;
+        if (unlikely(!pskb_may_pull(skb, len)))
+                return -ENOMEM;
+        return 0;
+}
+
+static bool arphdr_ok(struct sk_buff *skb)
+{
+        return pskb_may_pull(skb, skb_network_offset(skb) +
+                                  sizeof(struct arp_eth_header));
+}
+
+static int check_iphdr(struct sk_buff *skb)
+{
+        unsigned int nh_ofs = skb_network_offset(skb);
+        unsigned int ip_len;
+        int err;
+
+        err = check_header(skb, nh_ofs + sizeof(struct iphdr));
+        if (unlikely(err))
+                return err;
+
+        ip_len = ip_hdrlen(skb);
+        if (unlikely(ip_len < sizeof(struct iphdr) ||
+                     skb->len < nh_ofs + ip_len))
+                return -EINVAL;
+
+        skb_set_transport_header(skb, nh_ofs + ip_len);
+        return 0;
+}
+
+static bool tcphdr_ok(struct sk_buff *skb)
+{
+        int th_ofs = skb_transport_offset(skb);
+        int tcp_len;
+
+        if (unlikely(!pskb_may_pull(skb, th_ofs + sizeof(struct tcphdr))))
+                return false;
+
+        tcp_len = tcp_hdrlen(skb);
+        if (unlikely(tcp_len < sizeof(struct tcphdr) ||
+                     skb->len < th_ofs + tcp_len))
+                return false;
+
+        return true;
+}
+
+static bool udphdr_ok(struct sk_buff *skb)
+{
+        return pskb_may_pull(skb, skb_transport_offset(skb) +
+                                  sizeof(struct udphdr));
+}
+
+static bool icmphdr_ok(struct sk_buff *skb)
+{
+        return pskb_may_pull(skb, skb_transport_offset(skb) +
+                                  sizeof(struct icmphdr));
+}
+
+u64 ovs_flow_used_time(unsigned long flow_jiffies)
+{
+        struct timespec cur_ts;
+        u64 cur_ms, idle_ms;
+
+        ktime_get_ts(&cur_ts);
+        idle_ms = jiffies_to_msecs(jiffies - flow_jiffies);
+        cur_ms = (u64)cur_ts.tv_sec * MSEC_PER_SEC +
+                 cur_ts.tv_nsec / NSEC_PER_MSEC;
+
+        return cur_ms - idle_ms;
+}
+
+#define SW_FLOW_KEY_OFFSET(field)               \
+        (offsetof(struct sw_flow_key, field) +  \
+         FIELD_SIZEOF(struct sw_flow_key, field))
+
+static int parse_ipv6hdr(struct sk_buff *skb, struct sw_flow_key *key,
+                         int *key_lenp)
+{
+        unsigned int nh_ofs = skb_network_offset(skb);
+        unsigned int nh_len;
+        int payload_ofs;
+        struct ipv6hdr *nh;
+        uint8_t nexthdr;
+        __be16 frag_off;
+        int err;
+
+        *key_lenp = SW_FLOW_KEY_OFFSET(ipv6.label);
+
+        err = check_header(skb, nh_ofs + sizeof(*nh));
+        if (unlikely(err))
+                return err;
+
+        nh = ipv6_hdr(skb);
+        nexthdr = nh->nexthdr;
+        payload_ofs = (u8 *)(nh + 1) - skb->data;
+
+        key->ip.proto = NEXTHDR_NONE;
+        key->ip.tos = ipv6_get_dsfield(nh);
+        key->ip.ttl = nh->hop_limit;
+        key->ipv6.label = *(__be32 *)nh & htonl(IPV6_FLOWINFO_FLOWLABEL);
+        key->ipv6.addr.src = nh->saddr;
+        key->ipv6.addr.dst = nh->daddr;
+
+        payload_ofs = ipv6_skip_exthdr(skb, payload_ofs, &nexthdr, &frag_off);
+        if (unlikely(payload_ofs < 0))
+                return -EINVAL;
+
+        if (frag_off) {
+                if (frag_off & htons(~0x7))
+                        key->ip.frag = OVS_FRAG_TYPE_LATER;
+                else
+                        key->ip.frag = OVS_FRAG_TYPE_FIRST;
+        }
+
+        nh_len = payload_ofs - nh_ofs;
+        skb_set_transport_header(skb, nh_ofs + nh_len);
+        key->ip.proto = nexthdr;
+        return nh_len;
+}
+
+static bool icmp6hdr_ok(struct sk_buff *skb)
+{
+        return pskb_may_pull(skb, skb_transport_offset(skb) +
+                                  sizeof(struct icmp6hdr));
+}
+
+#define TCP_FLAGS_OFFSET 13
+#define TCP_FLAG_MASK 0x3f
+
+void ovs_flow_used(struct sw_flow *flow, struct sk_buff *skb)
+{
+        u8 tcp_flags = 0;
+
+        if (flow->key.eth.type == htons(ETH_P_IP) &&
+            flow->key.ip.proto == IPPROTO_TCP) {
+                u8 *tcp = (u8 *)tcp_hdr(skb);
+                tcp_flags = *(tcp + TCP_FLAGS_OFFSET) & TCP_FLAG_MASK;
+        }
+
+        spin_lock(&flow->lock);
+        flow->used = jiffies;
+        flow->packet_count++;
+        flow->byte_count += skb->len;
+        flow->tcp_flags |= tcp_flags;
+        spin_unlock(&flow->lock);
+}
+
+struct sw_flow_actions *ovs_flow_actions_alloc(const struct nlattr *actions)
+{
+        int actions_len = nla_len(actions);
+        struct sw_flow_actions *sfa;
+
+        /* At least DP_MAX_PORTS actions are required to be able to flood a
+         * packet to every port.  Factor of 2 allows for setting VLAN tags,
+         * etc. */
+        if (actions_len > 2 * DP_MAX_PORTS * nla_total_size(4))
+                return ERR_PTR(-EINVAL);
+
+        sfa = kmalloc(sizeof(*sfa) + actions_len, GFP_KERNEL);
+        if (!sfa)
+                return ERR_PTR(-ENOMEM);
+
+        sfa->actions_len = actions_len;
+        memcpy(sfa->actions, nla_data(actions), actions_len);
+        return sfa;
+}
+
+struct sw_flow *ovs_flow_alloc(void)
+{
+        struct sw_flow *flow;
+
+        flow = kmem_cache_alloc(flow_cache, GFP_KERNEL);
+        if (!flow)
+                return ERR_PTR(-ENOMEM);
+
+        spin_lock_init(&flow->lock);
+        flow->sf_acts = NULL;
+
+        return flow;
+}
+
+static struct hlist_head *find_bucket(struct flow_table *table, u32 hash)
+{
+        hash = jhash_1word(hash, table->hash_seed);
+        return flex_array_get(table->buckets,
+                                (hash & (table->n_buckets - 1)));
+}
+
+static struct flex_array *alloc_buckets(unsigned int n_buckets)
+{
+        struct flex_array *buckets;
+        int i, err;
+
+        buckets = flex_array_alloc(sizeof(struct hlist_head *),
+                                   n_buckets, GFP_KERNEL);
+        if (!buckets)
+                return NULL;
+
+        err = flex_array_prealloc(buckets, 0, n_buckets, GFP_KERNEL);
+        if (err) {
+                flex_array_free(buckets);
+                return NULL;
+        }
+
+        for (i = 0; i < n_buckets; i++)
+                INIT_HLIST_HEAD((struct hlist_head *)
+                                        flex_array_get(buckets, i));
+
+        return buckets;
+}
+
+static void free_buckets(struct flex_array *buckets)
+{
+        flex_array_free(buckets);
+}
+
+struct flow_table *ovs_flow_tbl_alloc(int new_size)
+{
+        struct flow_table *table = kmalloc(sizeof(*table), GFP_KERNEL);
+
+        if (!table)
+                return NULL;
+
+        table->buckets = alloc_buckets(new_size);
+
+        if (!table->buckets) {
+                kfree(table);
+                return NULL;
+        }
+        table->n_buckets = new_size;
+        table->count = 0;
+        table->node_ver = 0;
+        table->keep_flows = false;
+        get_random_bytes(&table->hash_seed, sizeof(u32));
+
+        return table;
+}
+
+void ovs_flow_tbl_destroy(struct flow_table *table)
+{
+        int i;
+
+        if (!table)
+                return;
+
+        if (table->keep_flows)
+                goto skip_flows;
+
+        for (i = 0; i < table->n_buckets; i++) {
+                struct sw_flow *flow;
+                struct hlist_head *head = flex_array_get(table->buckets, i);
+                struct hlist_node *node, *n;
+                int ver = table->node_ver;
+
+                hlist_for_each_entry_safe(flow, node, n, head, hash_node[ver]) {
+                        hlist_del_rcu(&flow->hash_node[ver]);
+                        ovs_flow_free(flow);
+                }
+        }
+
+skip_flows:
+        free_buckets(table->buckets);
+        kfree(table);
+}
+
+static void flow_tbl_destroy_rcu_cb(struct rcu_head *rcu)
+{
+        struct flow_table *table = container_of(rcu, struct flow_table, rcu);
+
+        ovs_flow_tbl_destroy(table);
+}
+
+void ovs_flow_tbl_deferred_destroy(struct flow_table *table)
+{
+        if (!table)
+                return;
+
+        call_rcu(&table->rcu, flow_tbl_destroy_rcu_cb);
+}
+
+struct sw_flow *ovs_flow_tbl_next(struct flow_table *table, u32 *bucket, u32 *last)
+{
+        struct sw_flow *flow;
+        struct hlist_head *head;
+        struct hlist_node *n;
+        int ver;
+        int i;
+
+        ver = table->node_ver;
+        while (*bucket < table->n_buckets) {
+                i = 0;
+                head = flex_array_get(table->buckets, *bucket);
+                hlist_for_each_entry_rcu(flow, n, head, hash_node[ver]) {
+                        if (i < *last) {
+                                i++;
+                                continue;
+                        }
+                        *last = i + 1;
+                        return flow;
+                }
+                (*bucket)++;
+                *last = 0;
+        }
+
+        return NULL;
+}
+
+static void flow_table_copy_flows(struct flow_table *old, struct flow_table *new)
+{
+        int old_ver;
+        int i;
+
+        old_ver = old->node_ver;
+        new->node_ver = !old_ver;
+
+        /* Insert in new table. */
+        for (i = 0; i < old->n_buckets; i++) {
+                struct sw_flow *flow;
+                struct hlist_head *head;
+                struct hlist_node *n;
+
+                head = flex_array_get(old->buckets, i);
+
+                hlist_for_each_entry(flow, n, head, hash_node[old_ver])
+                        ovs_flow_tbl_insert(new, flow);
+        }
+        old->keep_flows = true;
+}
+
+static struct flow_table *__flow_tbl_rehash(struct flow_table *table, int n_buckets)
+{
+        struct flow_table *new_table;
+
+        new_table = ovs_flow_tbl_alloc(n_buckets);
+        if (!new_table)
+                return ERR_PTR(-ENOMEM);
+
+        flow_table_copy_flows(table, new_table);
+
+        return new_table;
+}
+
+struct flow_table *ovs_flow_tbl_rehash(struct flow_table *table)
+{
+        return __flow_tbl_rehash(table, table->n_buckets);
+}
+
+struct flow_table *ovs_flow_tbl_expand(struct flow_table *table)
+{
+        return __flow_tbl_rehash(table, table->n_buckets * 2);
+}
+
+void ovs_flow_free(struct sw_flow *flow)
+{
+        if (unlikely(!flow))
+                return;
+
+        kfree((struct sf_flow_acts __force *)flow->sf_acts);
+        kmem_cache_free(flow_cache, flow);
+}
+
+/* RCU callback used by ovs_flow_deferred_free. */
+static void rcu_free_flow_callback(struct rcu_head *rcu)
+{
+        struct sw_flow *flow = container_of(rcu, struct sw_flow, rcu);
+
+        ovs_flow_free(flow);
+}
+
+/* Schedules 'flow' to be freed after the next RCU grace period.
+ * The caller must hold rcu_read_lock for this to be sensible. */
+void ovs_flow_deferred_free(struct sw_flow *flow)
+{
+        call_rcu(&flow->rcu, rcu_free_flow_callback);
+}
+
+/* RCU callback used by ovs_flow_deferred_free_acts. */
+static void rcu_free_acts_callback(struct rcu_head *rcu)
+{
+        struct sw_flow_actions *sf_acts = container_of(rcu,
+                        struct sw_flow_actions, rcu);
+        kfree(sf_acts);
+}
+
+/* Schedules 'sf_acts' to be freed after the next RCU grace period.
+ * The caller must hold rcu_read_lock for this to be sensible. */
+void ovs_flow_deferred_free_acts(struct sw_flow_actions *sf_acts)
+{
+        call_rcu(&sf_acts->rcu, rcu_free_acts_callback);
+}
+
+static int parse_vlan(struct sk_buff *skb, struct sw_flow_key *key)
+{
+        struct qtag_prefix {
+                __be16 eth_type; /* ETH_P_8021Q */
+                __be16 tci;
+        };
+        struct qtag_prefix *qp;
+
+        if (unlikely(skb->len < sizeof(struct qtag_prefix) + sizeof(__be16)))
+                return 0;
+
+        if (unlikely(!pskb_may_pull(skb, sizeof(struct qtag_prefix) +
+                                         sizeof(__be16))))
+                return -ENOMEM;
+
+        qp = (struct qtag_prefix *) skb->data;
+        key->eth.tci = qp->tci | htons(VLAN_TAG_PRESENT);
+        __skb_pull(skb, sizeof(struct qtag_prefix));
+
+        return 0;
+}
+
+static __be16 parse_ethertype(struct sk_buff *skb)
+{
+        struct llc_snap_hdr {
+                u8  dsap;  /* Always 0xAA */
+                u8  ssap;  /* Always 0xAA */
+                u8  ctrl;
+                u8  oui[3];
+                __be16 ethertype;
+        };
+        struct llc_snap_hdr *llc;
+        __be16 proto;
+
+        proto = *(__be16 *) skb->data;
+        __skb_pull(skb, sizeof(__be16));
+
+        if (ntohs(proto) >= 1536)
+                return proto;
+
+        if (skb->len < sizeof(struct llc_snap_hdr))
+                return htons(ETH_P_802_2);
+
+        if (unlikely(!pskb_may_pull(skb, sizeof(struct llc_snap_hdr))))
+                return htons(0);
+
+        llc = (struct llc_snap_hdr *) skb->data;
+        if (llc->dsap != LLC_SAP_SNAP ||
+            llc->ssap != LLC_SAP_SNAP ||
+            (llc->oui[0] | llc->oui[1] | llc->oui[2]) != 0)
+                return htons(ETH_P_802_2);
+
+        __skb_pull(skb, sizeof(struct llc_snap_hdr));
+        return llc->ethertype;
+}
+
+static int parse_icmpv6(struct sk_buff *skb, struct sw_flow_key *key,
+                        int *key_lenp, int nh_len)
+{
+        struct icmp6hdr *icmp = icmp6_hdr(skb);
+        int error = 0;
+        int key_len;
+
+        /* The ICMPv6 type and code fields use the 16-bit transport port
+         * fields, so we need to store them in 16-bit network byte order.
+         */
+        key->ipv6.tp.src = htons(icmp->icmp6_type);
+        key->ipv6.tp.dst = htons(icmp->icmp6_code);
+        key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
+
+        if (icmp->icmp6_code == 0 &&
+            (icmp->icmp6_type == NDISC_NEIGHBOUR_SOLICITATION ||
+             icmp->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT)) {
+                int icmp_len = skb->len - skb_transport_offset(skb);
+                struct nd_msg *nd;
+                int offset;
+
+                key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
+
+                /* In order to process neighbor discovery options, we need the
+                 * entire packet.
+                 */
+                if (unlikely(icmp_len < sizeof(*nd)))
+                        goto out;
+                if (unlikely(skb_linearize(skb))) {
+                        error = -ENOMEM;
+                        goto out;
+                }
+
+                nd = (struct nd_msg *)skb_transport_header(skb);
+                key->ipv6.nd.target = nd->target;
+                key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
+
+                icmp_len -= sizeof(*nd);
+                offset = 0;
+                while (icmp_len >= 8) {
+                        struct nd_opt_hdr *nd_opt =
+                                 (struct nd_opt_hdr *)(nd->opt + offset);
+                        int opt_len = nd_opt->nd_opt_len * 8;
+
+                        if (unlikely(!opt_len || opt_len > icmp_len))
+                                goto invalid;
+
+                        /* Store the link layer address if the appropriate
+                         * option is provided.  It is considered an error if
+                         * the same link layer option is specified twice.
+                         */
+                        if (nd_opt->nd_opt_type == ND_OPT_SOURCE_LL_ADDR
+                            && opt_len == 8) {
+                                if (unlikely(!is_zero_ether_addr(key->ipv6.nd.sll)))
+                                        goto invalid;
+                                memcpy(key->ipv6.nd.sll,
+                                    &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
+                        } else if (nd_opt->nd_opt_type == ND_OPT_TARGET_LL_ADDR
+                                   && opt_len == 8) {
+                                if (unlikely(!is_zero_ether_addr(key->ipv6.nd.tll)))
+                                        goto invalid;
+                                memcpy(key->ipv6.nd.tll,
+                                    &nd->opt[offset+sizeof(*nd_opt)], ETH_ALEN);
+                        }
+
+                        icmp_len -= opt_len;
+                        offset += opt_len;
+                }
+        }
+
+        goto out;
+
+invalid:
+        memset(&key->ipv6.nd.target, 0, sizeof(key->ipv6.nd.target));
+        memset(key->ipv6.nd.sll, 0, sizeof(key->ipv6.nd.sll));
+        memset(key->ipv6.nd.tll, 0, sizeof(key->ipv6.nd.tll));
+
+out:
+        *key_lenp = key_len;
+        return error;
+}
+
+/**
+ * ovs_flow_extract - extracts a flow key from an Ethernet frame.
+ * @skb: sk_buff that contains the frame, with skb->data pointing to the
+ * Ethernet header
+ * @in_port: port number on which @skb was received.
+ * @key: output flow key
+ * @key_lenp: length of output flow key
+ *
+ * The caller must ensure that skb->len >= ETH_HLEN.
+ *
+ * Returns 0 if successful, otherwise a negative errno value.
+ *
+ * Initializes @skb header pointers as follows:
+ *
+ *    - skb->mac_header: the Ethernet header.
+ *
+ *    - skb->network_header: just past the Ethernet header, or just past the
+ *      VLAN header, to the first byte of the Ethernet payload.
+ *
+ *    - skb->transport_header: If key->dl_type is ETH_P_IP or ETH_P_IPV6
+ *      on output, then just past the IP header, if one is present and
+ *      of a correct length, otherwise the same as skb->network_header.
+ *      For other key->dl_type values it is left untouched.
+ */
+int ovs_flow_extract(struct sk_buff *skb, u16 in_port, struct sw_flow_key *key,
+                 int *key_lenp)
+{
+        int error = 0;
+        int key_len = SW_FLOW_KEY_OFFSET(eth);
+        struct ethhdr *eth;
+
+        memset(key, 0, sizeof(*key));
+
+        key->phy.priority = skb->priority;
+        key->phy.in_port = in_port;
+
+        skb_reset_mac_header(skb);
+
+        /* Link layer.  We are guaranteed to have at least the 14 byte Ethernet
+         * header in the linear data area.
+         */
+        eth = eth_hdr(skb);
+        memcpy(key->eth.src, eth->h_source, ETH_ALEN);
+        memcpy(key->eth.dst, eth->h_dest, ETH_ALEN);
+
+        __skb_pull(skb, 2 * ETH_ALEN);
+
+        if (vlan_tx_tag_present(skb))
+                key->eth.tci = htons(skb->vlan_tci);
+        else if (eth->h_proto == htons(ETH_P_8021Q))
+                if (unlikely(parse_vlan(skb, key)))
+                        return -ENOMEM;
+
+        key->eth.type = parse_ethertype(skb);
+        if (unlikely(key->eth.type == htons(0)))
+                return -ENOMEM;
+
+        skb_reset_network_header(skb);
+        __skb_push(skb, skb->data - skb_mac_header(skb));
+
+        /* Network layer. */
+        if (key->eth.type == htons(ETH_P_IP)) {
+                struct iphdr *nh;
+                __be16 offset;
+
+                key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
+
+                error = check_iphdr(skb);
+                if (unlikely(error)) {
+                        if (error == -EINVAL) {
+                                skb->transport_header = skb->network_header;
+                                error = 0;
+                        }
+                        goto out;
+                }
+
+                nh = ip_hdr(skb);
+                key->ipv4.addr.src = nh->saddr;
+                key->ipv4.addr.dst = nh->daddr;
+
+                key->ip.proto = nh->protocol;
+                key->ip.tos = nh->tos;
+                key->ip.ttl = nh->ttl;
+
+                offset = nh->frag_off & htons(IP_OFFSET);
+                if (offset) {
+                        key->ip.frag = OVS_FRAG_TYPE_LATER;
+                        goto out;
+                }
+                if (nh->frag_off & htons(IP_MF) ||
+                         skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
+                        key->ip.frag = OVS_FRAG_TYPE_FIRST;
+
+                /* Transport layer. */
+                if (key->ip.proto == IPPROTO_TCP) {
+                        key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
+                        if (tcphdr_ok(skb)) {
+                                struct tcphdr *tcp = tcp_hdr(skb);
+                                key->ipv4.tp.src = tcp->source;
+                                key->ipv4.tp.dst = tcp->dest;
+                        }
+                } else if (key->ip.proto == IPPROTO_UDP) {
+                        key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
+                        if (udphdr_ok(skb)) {
+                                struct udphdr *udp = udp_hdr(skb);
+                                key->ipv4.tp.src = udp->source;
+                                key->ipv4.tp.dst = udp->dest;
+                        }
+                } else if (key->ip.proto == IPPROTO_ICMP) {
+                        key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
+                        if (icmphdr_ok(skb)) {
+                                struct icmphdr *icmp = icmp_hdr(skb);
+                                /* The ICMP type and code fields use the 16-bit
+                                 * transport port fields, so we need to store
+                                 * them in 16-bit network byte order. */
+                                key->ipv4.tp.src = htons(icmp->type);
+                                key->ipv4.tp.dst = htons(icmp->code);
+                        }
+                }
+
+        } else if (key->eth.type == htons(ETH_P_ARP) && arphdr_ok(skb)) {
+                struct arp_eth_header *arp;
+
+                arp = (struct arp_eth_header *)skb_network_header(skb);
+
+                if (arp->ar_hrd == htons(ARPHRD_ETHER)
+                                && arp->ar_pro == htons(ETH_P_IP)
+                                && arp->ar_hln == ETH_ALEN
+                                && arp->ar_pln == 4) {
+
+                        /* We only match on the lower 8 bits of the opcode. */
+                        if (ntohs(arp->ar_op) <= 0xff)
+                                key->ip.proto = ntohs(arp->ar_op);
+
+                        if (key->ip.proto == ARPOP_REQUEST
+                                        || key->ip.proto == ARPOP_REPLY) {
+                                memcpy(&key->ipv4.addr.src, arp->ar_sip, sizeof(key->ipv4.addr.src));
+                                memcpy(&key->ipv4.addr.dst, arp->ar_tip, sizeof(key->ipv4.addr.dst));
+                                memcpy(key->ipv4.arp.sha, arp->ar_sha, ETH_ALEN);
+                                memcpy(key->ipv4.arp.tha, arp->ar_tha, ETH_ALEN);
+                                key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
+                        }
+                }
+        } else if (key->eth.type == htons(ETH_P_IPV6)) {
+                int nh_len;             /* IPv6 Header + Extensions */
+
+                nh_len = parse_ipv6hdr(skb, key, &key_len);
+                if (unlikely(nh_len < 0)) {
+                        if (nh_len == -EINVAL)
+                                skb->transport_header = skb->network_header;
+                        else
+                                error = nh_len;
+                        goto out;
+                }
+
+                if (key->ip.frag == OVS_FRAG_TYPE_LATER)
+                        goto out;
+                if (skb_shinfo(skb)->gso_type & SKB_GSO_UDP)
+                        key->ip.frag = OVS_FRAG_TYPE_FIRST;
+
+                /* Transport layer. */
+                if (key->ip.proto == NEXTHDR_TCP) {
+                        key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
+                        if (tcphdr_ok(skb)) {
+                                struct tcphdr *tcp = tcp_hdr(skb);
+                                key->ipv6.tp.src = tcp->source;
+                                key->ipv6.tp.dst = tcp->dest;
+                        }
+                } else if (key->ip.proto == NEXTHDR_UDP) {
+                        key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
+                        if (udphdr_ok(skb)) {
+                                struct udphdr *udp = udp_hdr(skb);
+                                key->ipv6.tp.src = udp->source;
+                                key->ipv6.tp.dst = udp->dest;
+                        }
+                } else if (key->ip.proto == NEXTHDR_ICMP) {
+                        key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
+                        if (icmp6hdr_ok(skb)) {
+                                error = parse_icmpv6(skb, key, &key_len, nh_len);
+                                if (error < 0)
+                                        goto out;
+                        }
+                }
+        }
+
+out:
+        *key_lenp = key_len;
+        return error;
+}
+
+u32 ovs_flow_hash(const struct sw_flow_key *key, int key_len)
+{
+        return jhash2((u32 *)key, DIV_ROUND_UP(key_len, sizeof(u32)), 0);
+}
+
+struct sw_flow *ovs_flow_tbl_lookup(struct flow_table *table,
+                                struct sw_flow_key *key, int key_len)
+{
+        struct sw_flow *flow;
+        struct hlist_node *n;
+        struct hlist_head *head;
+        u32 hash;
+
+        hash = ovs_flow_hash(key, key_len);
+
+        head = find_bucket(table, hash);
+        hlist_for_each_entry_rcu(flow, n, head, hash_node[table->node_ver]) {
+
+                if (flow->hash == hash &&
+                    !memcmp(&flow->key, key, key_len)) {
+                        return flow;
+                }
+        }
+        return NULL;
+}
+
+void ovs_flow_tbl_insert(struct flow_table *table, struct sw_flow *flow)
+{
+        struct hlist_head *head;
+
+        head = find_bucket(table, flow->hash);
+        hlist_add_head_rcu(&flow->hash_node[table->node_ver], head);
+        table->count++;
+}
+
+void ovs_flow_tbl_remove(struct flow_table *table, struct sw_flow *flow)
+{
+        hlist_del_rcu(&flow->hash_node[table->node_ver]);
+        table->count--;
+        BUG_ON(table->count < 0);
+}
+
+/* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
+const int ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
+        [OVS_KEY_ATTR_ENCAP] = -1,
+        [OVS_KEY_ATTR_PRIORITY] = sizeof(u32),
+        [OVS_KEY_ATTR_IN_PORT] = sizeof(u32),
+        [OVS_KEY_ATTR_ETHERNET] = sizeof(struct ovs_key_ethernet),
+        [OVS_KEY_ATTR_VLAN] = sizeof(__be16),
+        [OVS_KEY_ATTR_ETHERTYPE] = sizeof(__be16),
+        [OVS_KEY_ATTR_IPV4] = sizeof(struct ovs_key_ipv4),
+        [OVS_KEY_ATTR_IPV6] = sizeof(struct ovs_key_ipv6),
+        [OVS_KEY_ATTR_TCP] = sizeof(struct ovs_key_tcp),
+        [OVS_KEY_ATTR_UDP] = sizeof(struct ovs_key_udp),
+        [OVS_KEY_ATTR_ICMP] = sizeof(struct ovs_key_icmp),
+        [OVS_KEY_ATTR_ICMPV6] = sizeof(struct ovs_key_icmpv6),
+        [OVS_KEY_ATTR_ARP] = sizeof(struct ovs_key_arp),
+        [OVS_KEY_ATTR_ND] = sizeof(struct ovs_key_nd),
+};
+
+static int ipv4_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
+                                  const struct nlattr *a[], u32 *attrs)
+{
+        const struct ovs_key_icmp *icmp_key;
+        const struct ovs_key_tcp *tcp_key;
+        const struct ovs_key_udp *udp_key;
+
+        switch (swkey->ip.proto) {
+        case IPPROTO_TCP:
+                if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
+                        return -EINVAL;
+                *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
+
+                *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
+                tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
+                swkey->ipv4.tp.src = tcp_key->tcp_src;
+                swkey->ipv4.tp.dst = tcp_key->tcp_dst;
+                break;
+
+        case IPPROTO_UDP:
+                if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
+                        return -EINVAL;
+                *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
+
+                *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
+                udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
+                swkey->ipv4.tp.src = udp_key->udp_src;
+                swkey->ipv4.tp.dst = udp_key->udp_dst;
+                break;
+
+        case IPPROTO_ICMP:
+                if (!(*attrs & (1 << OVS_KEY_ATTR_ICMP)))
+                        return -EINVAL;
+                *attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
+
+                *key_len = SW_FLOW_KEY_OFFSET(ipv4.tp);
+                icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
+                swkey->ipv4.tp.src = htons(icmp_key->icmp_type);
+                swkey->ipv4.tp.dst = htons(icmp_key->icmp_code);
+                break;
+        }
+
+        return 0;
+}
+
+static int ipv6_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_len,
+                                  const struct nlattr *a[], u32 *attrs)
+{
+        const struct ovs_key_icmpv6 *icmpv6_key;
+        const struct ovs_key_tcp *tcp_key;
+        const struct ovs_key_udp *udp_key;
+
+        switch (swkey->ip.proto) {
+        case IPPROTO_TCP:
+                if (!(*attrs & (1 << OVS_KEY_ATTR_TCP)))
+                        return -EINVAL;
+                *attrs &= ~(1 << OVS_KEY_ATTR_TCP);
+
+                *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
+                tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
+                swkey->ipv6.tp.src = tcp_key->tcp_src;
+                swkey->ipv6.tp.dst = tcp_key->tcp_dst;
+                break;
+
+        case IPPROTO_UDP:
+                if (!(*attrs & (1 << OVS_KEY_ATTR_UDP)))
+                        return -EINVAL;
+                *attrs &= ~(1 << OVS_KEY_ATTR_UDP);
+
+                *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
+                udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
+                swkey->ipv6.tp.src = udp_key->udp_src;
+                swkey->ipv6.tp.dst = udp_key->udp_dst;
+                break;
+
+        case IPPROTO_ICMPV6:
+                if (!(*attrs & (1 << OVS_KEY_ATTR_ICMPV6)))
+                        return -EINVAL;
+                *attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
+
+                *key_len = SW_FLOW_KEY_OFFSET(ipv6.tp);
+                icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
+                swkey->ipv6.tp.src = htons(icmpv6_key->icmpv6_type);
+                swkey->ipv6.tp.dst = htons(icmpv6_key->icmpv6_code);
+
+                if (swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_SOLICITATION) ||
+                    swkey->ipv6.tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
+                        const struct ovs_key_nd *nd_key;
+
+                        if (!(*attrs & (1 << OVS_KEY_ATTR_ND)))
+                                return -EINVAL;
+                        *attrs &= ~(1 << OVS_KEY_ATTR_ND);
+
+                        *key_len = SW_FLOW_KEY_OFFSET(ipv6.nd);
+                        nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
+                        memcpy(&swkey->ipv6.nd.target, nd_key->nd_target,
+                               sizeof(swkey->ipv6.nd.target));
+                        memcpy(swkey->ipv6.nd.sll, nd_key->nd_sll, ETH_ALEN);
+                        memcpy(swkey->ipv6.nd.tll, nd_key->nd_tll, ETH_ALEN);
+                }
+                break;
+        }
+
+        return 0;
+}
+
+static int parse_flow_nlattrs(const struct nlattr *attr,
+                              const struct nlattr *a[], u32 *attrsp)
+{
+        const struct nlattr *nla;
+        u32 attrs;
+        int rem;
+
+        attrs = 0;
+        nla_for_each_nested(nla, attr, rem) {
+                u16 type = nla_type(nla);
+                int expected_len;
+
+                if (type > OVS_KEY_ATTR_MAX || attrs & (1 << type))
+                        return -EINVAL;
+
+                expected_len = ovs_key_lens[type];
+                if (nla_len(nla) != expected_len && expected_len != -1)
+                        return -EINVAL;
+
+                attrs |= 1 << type;
+                a[type] = nla;
+        }
+        if (rem)
+                return -EINVAL;
+
+        *attrsp = attrs;
+        return 0;
+}
+
+/**
+ * ovs_flow_from_nlattrs - parses Netlink attributes into a flow key.
+ * @swkey: receives the extracted flow key.
+ * @key_lenp: number of bytes used in @swkey.
+ * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
+ * sequence.
+ */
+int ovs_flow_from_nlattrs(struct sw_flow_key *swkey, int *key_lenp,
+                      const struct nlattr *attr)
+{
+        const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
+        const struct ovs_key_ethernet *eth_key;
+        int key_len;
+        u32 attrs;
+        int err;
+
+        memset(swkey, 0, sizeof(struct sw_flow_key));
+        key_len = SW_FLOW_KEY_OFFSET(eth);
+
+        err = parse_flow_nlattrs(attr, a, &attrs);
+        if (err)
+                return err;
+
+        /* Metadata attributes. */
+        if (attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
+                swkey->phy.priority = nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]);
+                attrs &= ~(1 << OVS_KEY_ATTR_PRIORITY);
+        }
+        if (attrs & (1 << OVS_KEY_ATTR_IN_PORT)) {
+                u32 in_port = nla_get_u32(a[OVS_KEY_ATTR_IN_PORT]);
+                if (in_port >= DP_MAX_PORTS)
+                        return -EINVAL;
+                swkey->phy.in_port = in_port;
+                attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
+        } else {
+                swkey->phy.in_port = USHRT_MAX;
+        }
+
+        /* Data attributes. */
+        if (!(attrs & (1 << OVS_KEY_ATTR_ETHERNET)))
+                return -EINVAL;
+        attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
+
+        eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
+        memcpy(swkey->eth.src, eth_key->eth_src, ETH_ALEN);
+        memcpy(swkey->eth.dst, eth_key->eth_dst, ETH_ALEN);
+
+        if (attrs & (1u << OVS_KEY_ATTR_ETHERTYPE) &&
+            nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q)) {
+                const struct nlattr *encap;
+                __be16 tci;
+
+                if (attrs != ((1 << OVS_KEY_ATTR_VLAN) |
+                              (1 << OVS_KEY_ATTR_ETHERTYPE) |
+                              (1 << OVS_KEY_ATTR_ENCAP)))
+                        return -EINVAL;
+
+                encap = a[OVS_KEY_ATTR_ENCAP];
+                tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
+                if (tci & htons(VLAN_TAG_PRESENT)) {
+                        swkey->eth.tci = tci;
+
+                        err = parse_flow_nlattrs(encap, a, &attrs);
+                        if (err)
+                                return err;
+                } else if (!tci) {
+                        /* Corner case for truncated 802.1Q header. */
+                        if (nla_len(encap))
+                                return -EINVAL;
+
+                        swkey->eth.type = htons(ETH_P_8021Q);
+                        *key_lenp = key_len;
+                        return 0;
+                } else {
+                        return -EINVAL;
+                }
+        }
+
+        if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
+                swkey->eth.type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
+                if (ntohs(swkey->eth.type) < 1536)
+                        return -EINVAL;
+                attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
+        } else {
+                swkey->eth.type = htons(ETH_P_802_2);
+        }
+
+        if (swkey->eth.type == htons(ETH_P_IP)) {
+                const struct ovs_key_ipv4 *ipv4_key;
+
+                if (!(attrs & (1 << OVS_KEY_ATTR_IPV4)))
+                        return -EINVAL;
+                attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
+
+                key_len = SW_FLOW_KEY_OFFSET(ipv4.addr);
+                ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
+                if (ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX)
+                        return -EINVAL;
+                swkey->ip.proto = ipv4_key->ipv4_proto;
+                swkey->ip.tos = ipv4_key->ipv4_tos;
+                swkey->ip.ttl = ipv4_key->ipv4_ttl;
+                swkey->ip.frag = ipv4_key->ipv4_frag;
+                swkey->ipv4.addr.src = ipv4_key->ipv4_src;
+                swkey->ipv4.addr.dst = ipv4_key->ipv4_dst;
+
+                if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
+                        err = ipv4_flow_from_nlattrs(swkey, &key_len, a, &attrs);
+                        if (err)
+                                return err;
+                }
+        } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
+                const struct ovs_key_ipv6 *ipv6_key;
+
+                if (!(attrs & (1 << OVS_KEY_ATTR_IPV6)))
+                        return -EINVAL;
+                attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
+
+                key_len = SW_FLOW_KEY_OFFSET(ipv6.label);
+                ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
+                if (ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX)
+                        return -EINVAL;
+                swkey->ipv6.label = ipv6_key->ipv6_label;
+                swkey->ip.proto = ipv6_key->ipv6_proto;
+                swkey->ip.tos = ipv6_key->ipv6_tclass;
+                swkey->ip.ttl = ipv6_key->ipv6_hlimit;
+                swkey->ip.frag = ipv6_key->ipv6_frag;
+                memcpy(&swkey->ipv6.addr.src, ipv6_key->ipv6_src,
+                       sizeof(swkey->ipv6.addr.src));
+                memcpy(&swkey->ipv6.addr.dst, ipv6_key->ipv6_dst,
+                       sizeof(swkey->ipv6.addr.dst));
+
+                if (swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
+                        err = ipv6_flow_from_nlattrs(swkey, &key_len, a, &attrs);
+                        if (err)
+                                return err;
+                }
+        } else if (swkey->eth.type == htons(ETH_P_ARP)) {
+                const struct ovs_key_arp *arp_key;
+
+                if (!(attrs & (1 << OVS_KEY_ATTR_ARP)))
+                        return -EINVAL;
+                attrs &= ~(1 << OVS_KEY_ATTR_ARP);
+
+                key_len = SW_FLOW_KEY_OFFSET(ipv4.arp);
+                arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
+                swkey->ipv4.addr.src = arp_key->arp_sip;
+                swkey->ipv4.addr.dst = arp_key->arp_tip;
+                if (arp_key->arp_op & htons(0xff00))
+                        return -EINVAL;
+                swkey->ip.proto = ntohs(arp_key->arp_op);
+                memcpy(swkey->ipv4.arp.sha, arp_key->arp_sha, ETH_ALEN);
+                memcpy(swkey->ipv4.arp.tha, arp_key->arp_tha, ETH_ALEN);
+        }
+
+        if (attrs)
+                return -EINVAL;
+        *key_lenp = key_len;
+
+        return 0;
+}
+
+/**
+ * ovs_flow_metadata_from_nlattrs - parses Netlink attributes into a flow key.
+ * @in_port: receives the extracted input port.
+ * @key: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
+ * sequence.
+ *
+ * This parses a series of Netlink attributes that form a flow key, which must
+ * take the same form accepted by flow_from_nlattrs(), but only enough of it to
+ * get the metadata, that is, the parts of the flow key that cannot be
+ * extracted from the packet itself.
+ */
+int ovs_flow_metadata_from_nlattrs(u32 *priority, u16 *in_port,
+                               const struct nlattr *attr)
+{
+        const struct nlattr *nla;
+        int rem;
+
+        *in_port = USHRT_MAX;
+        *priority = 0;
+
+        nla_for_each_nested(nla, attr, rem) {
+                int type = nla_type(nla);
+
+                if (type <= OVS_KEY_ATTR_MAX && ovs_key_lens[type] > 0) {
+                        if (nla_len(nla) != ovs_key_lens[type])
+                                return -EINVAL;
+
+                        switch (type) {
+                        case OVS_KEY_ATTR_PRIORITY:
+                                *priority = nla_get_u32(nla);
+                                break;
+
+                        case OVS_KEY_ATTR_IN_PORT:
+                                if (nla_get_u32(nla) >= DP_MAX_PORTS)
+                                        return -EINVAL;
+                                *in_port = nla_get_u32(nla);
+                                break;
+                        }
+                }
+        }
+        if (rem)
+                return -EINVAL;
+        return 0;
+}
+
+int ovs_flow_to_nlattrs(const struct sw_flow_key *swkey, struct sk_buff *skb)
+{
+        struct ovs_key_ethernet *eth_key;
+        struct nlattr *nla, *encap;
+
+        if (swkey->phy.priority)
+                NLA_PUT_U32(skb, OVS_KEY_ATTR_PRIORITY, swkey->phy.priority);
+
+        if (swkey->phy.in_port != USHRT_MAX)
+                NLA_PUT_U32(skb, OVS_KEY_ATTR_IN_PORT, swkey->phy.in_port);
+
+        nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
+        if (!nla)
+                goto nla_put_failure;
+        eth_key = nla_data(nla);
+        memcpy(eth_key->eth_src, swkey->eth.src, ETH_ALEN);
+        memcpy(eth_key->eth_dst, swkey->eth.dst, ETH_ALEN);
+
+        if (swkey->eth.tci || swkey->eth.type == htons(ETH_P_8021Q)) {
+                NLA_PUT_BE16(skb, OVS_KEY_ATTR_ETHERTYPE, htons(ETH_P_8021Q));
+                NLA_PUT_BE16(skb, OVS_KEY_ATTR_VLAN, swkey->eth.tci);
+                encap = nla_nest_start(skb, OVS_KEY_ATTR_ENCAP);
+                if (!swkey->eth.tci)
+                        goto unencap;
+        } else {
+                encap = NULL;
+        }
+
+        if (swkey->eth.type == htons(ETH_P_802_2))
+                goto unencap;
+
+        NLA_PUT_BE16(skb, OVS_KEY_ATTR_ETHERTYPE, swkey->eth.type);
+
+        if (swkey->eth.type == htons(ETH_P_IP)) {
+                struct ovs_key_ipv4 *ipv4_key;
+
+                nla = nla_reserve(skb, OVS_KEY_ATTR_IPV4, sizeof(*ipv4_key));
+                if (!nla)
+                        goto nla_put_failure;
+                ipv4_key = nla_data(nla);
+                ipv4_key->ipv4_src = swkey->ipv4.addr.src;
+                ipv4_key->ipv4_dst = swkey->ipv4.addr.dst;
+                ipv4_key->ipv4_proto = swkey->ip.proto;
+                ipv4_key->ipv4_tos = swkey->ip.tos;
+                ipv4_key->ipv4_ttl = swkey->ip.ttl;
+                ipv4_key->ipv4_frag = swkey->ip.frag;
+        } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
+                struct ovs_key_ipv6 *ipv6_key;
+
+                nla = nla_reserve(skb, OVS_KEY_ATTR_IPV6, sizeof(*ipv6_key));
+                if (!nla)
+                        goto nla_put_failure;
+                ipv6_key = nla_data(nla);
+                memcpy(ipv6_key->ipv6_src, &swkey->ipv6.addr.src,
+                                sizeof(ipv6_key->ipv6_src));
+                memcpy(ipv6_key->ipv6_dst, &swkey->ipv6.addr.dst,
+                                sizeof(ipv6_key->ipv6_dst));
+                ipv6_key->ipv6_label = swkey->ipv6.label;
+                ipv6_key->ipv6_proto = swkey->ip.proto;
+                ipv6_key->ipv6_tclass = swkey->ip.tos;
+                ipv6_key->ipv6_hlimit = swkey->ip.ttl;
+                ipv6_key->ipv6_frag = swkey->ip.frag;
+        } else if (swkey->eth.type == htons(ETH_P_ARP)) {
+                struct ovs_key_arp *arp_key;
+
+                nla = nla_reserve(skb, OVS_KEY_ATTR_ARP, sizeof(*arp_key));
+                if (!nla)
+                        goto nla_put_failure;
+                arp_key = nla_data(nla);
+                memset(arp_key, 0, sizeof(struct ovs_key_arp));
+                arp_key->arp_sip = swkey->ipv4.addr.src;
+                arp_key->arp_tip = swkey->ipv4.addr.dst;
+                arp_key->arp_op = htons(swkey->ip.proto);
+                memcpy(arp_key->arp_sha, swkey->ipv4.arp.sha, ETH_ALEN);
+                memcpy(arp_key->arp_tha, swkey->ipv4.arp.tha, ETH_ALEN);
+        }
+
+        if ((swkey->eth.type == htons(ETH_P_IP) ||
+             swkey->eth.type == htons(ETH_P_IPV6)) &&
+             swkey->ip.frag != OVS_FRAG_TYPE_LATER) {
+
+                if (swkey->ip.proto == IPPROTO_TCP) {
+                        struct ovs_key_tcp *tcp_key;
+
+                        nla = nla_reserve(skb, OVS_KEY_ATTR_TCP, sizeof(*tcp_key));
+                        if (!nla)
+                                goto nla_put_failure;
+                        tcp_key = nla_data(nla);
+                        if (swkey->eth.type == htons(ETH_P_IP)) {
+                                tcp_key->tcp_src = swkey->ipv4.tp.src;
+                                tcp_key->tcp_dst = swkey->ipv4.tp.dst;
+                        } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
+                                tcp_key->tcp_src = swkey->ipv6.tp.src;
+                                tcp_key->tcp_dst = swkey->ipv6.tp.dst;
+                        }
+                } else if (swkey->ip.proto == IPPROTO_UDP) {
+                        struct ovs_key_udp *udp_key;
+
+                        nla = nla_reserve(skb, OVS_KEY_ATTR_UDP, sizeof(*udp_key));
+                        if (!nla)
+                                goto nla_put_failure;
+                        udp_key = nla_data(nla);
+                        if (swkey->eth.type == htons(ETH_P_IP)) {
+                                udp_key->udp_src = swkey->ipv4.tp.src;
+                                udp_key->udp_dst = swkey->ipv4.tp.dst;
+                        } else if (swkey->eth.type == htons(ETH_P_IPV6)) {
+                                udp_key->udp_src = swkey->ipv6.tp.src;
+                                udp_key->udp_dst = swkey->ipv6.tp.dst;
+                        }
+                } else if (swkey->eth.type == htons(ETH_P_IP) &&
+                           swkey->ip.proto == IPPROTO_ICMP) {
+                        struct ovs_key_icmp *icmp_key;
+
+                        nla = nla_reserve(skb, OVS_KEY_ATTR_ICMP, sizeof(*icmp_key));
+                        if (!nla)
+                                goto nla_put_failure;
+                        icmp_key = nla_data(nla);
+                        icmp_key->icmp_type = ntohs(swkey->ipv4.tp.src);
+                        icmp_key->icmp_code = ntohs(swkey->ipv4.tp.dst);
+                } else if (swkey->eth.type == htons(ETH_P_IPV6) &&
+                           swkey->ip.proto == IPPROTO_ICMPV6) {
+                        struct ovs_key_icmpv6 *icmpv6_key;
+
+                        nla = nla_reserve(skb, OVS_KEY_ATTR_ICMPV6,
+                                                sizeof(*icmpv6_key));
+                        if (!nla)
+                                goto nla_put_failure;
+                        icmpv6_key = nla_data(nla);
+                        icmpv6_key->icmpv6_type = ntohs(swkey->ipv6.tp.src);
+                        icmpv6_key->icmpv6_code = ntohs(swkey->ipv6.tp.dst);
+
+                        if (icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_SOLICITATION ||
+                            icmpv6_key->icmpv6_type == NDISC_NEIGHBOUR_ADVERTISEMENT) {
+                                struct ovs_key_nd *nd_key;
+
+                                nla = nla_reserve(skb, OVS_KEY_ATTR_ND, sizeof(*nd_key));
+                                if (!nla)
+                                        goto nla_put_failure;
+                                nd_key = nla_data(nla);
+                                memcpy(nd_key->nd_target, &swkey->ipv6.nd.target,
+                                                        sizeof(nd_key->nd_target));
+                                memcpy(nd_key->nd_sll, swkey->ipv6.nd.sll, ETH_ALEN);
+                                memcpy(nd_key->nd_tll, swkey->ipv6.nd.tll, ETH_ALEN);
+                        }
+                }
+        }
+
+unencap:
+        if (encap)
+                nla_nest_end(skb, encap);
+
+        return 0;
+
+nla_put_failure:
+        return -EMSGSIZE;
+}
+
+/* Initializes the flow module.
+ * Returns zero if successful or a negative error code. */
+int ovs_flow_init(void)
+{
+        flow_cache = kmem_cache_create("sw_flow", sizeof(struct sw_flow), 0,
+                                        0, NULL);
+        if (flow_cache == NULL)
+                return -ENOMEM;
+
+        return 0;
+}
+
+/* Uninitializes the flow module. */
+void ovs_flow_exit(void)
+{
+        kmem_cache_destroy(flow_cache);
+}