/*
 * Copyright (c) 2007-2014 Nicira, Inc.
 *
 * 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
 */

#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

#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/sctp.h>
#include <linux/tcp.h>
#include <linux/udp.h>
#include <linux/icmp.h>
#include <linux/icmpv6.h>
#include <linux/rculist.h>
#include <net/geneve.h>
#include <net/ip.h>
#include <net/ipv6.h>
#include <net/ndisc.h>
#include <net/mpls.h>
#include <net/vxlan.h>

#include "flow_netlink.h"

struct ovs_len_tbl {
        int len;
        const struct ovs_len_tbl *next;
};

#define OVS_ATTR_NESTED -1
#define OVS_ATTR_VARIABLE -2

static void update_range(struct sw_flow_match *match,
                         size_t offset, size_t size, bool is_mask)
{
        struct sw_flow_key_range *range;
        size_t start = rounddown(offset, sizeof(long));
        size_t end = roundup(offset + size, sizeof(long));

        if (!is_mask)
                range = &match->range;
        else
                range = &match->mask->range;

        if (range->start == range->end) {
                range->start = start;
                range->end = end;
                return;
        }

        if (range->start > start)
                range->start = start;

        if (range->end < end)
                range->end = end;
}

#define SW_FLOW_KEY_PUT(match, field, value, is_mask) \
        do { \
                update_range(match, offsetof(struct sw_flow_key, field),    \
                             sizeof((match)->key->field), is_mask);         \
                if (is_mask)                                                \
                        (match)->mask->key.field = value;                   \
                else                                                        \
                        (match)->key->field = value;                        \
        } while (0)

#define SW_FLOW_KEY_MEMCPY_OFFSET(match, offset, value_p, len, is_mask)     \
        do {                                                                \
                update_range(match, offset, len, is_mask);                  \
                if (is_mask)                                                \
                        memcpy((u8 *)&(match)->mask->key + offset, value_p, \
                               len);                                       \
                else                                                        \
                        memcpy((u8 *)(match)->key + offset, value_p, len);  \
        } while (0)

#define SW_FLOW_KEY_MEMCPY(match, field, value_p, len, is_mask)               \
        SW_FLOW_KEY_MEMCPY_OFFSET(match, offsetof(struct sw_flow_key, field), \
                                  value_p, len, is_mask)

#define SW_FLOW_KEY_MEMSET_FIELD(match, field, value, is_mask)              \
        do {                                                                \
                update_range(match, offsetof(struct sw_flow_key, field),    \
                             sizeof((match)->key->field), is_mask);         \
                if (is_mask)                                                \
                        memset((u8 *)&(match)->mask->key.field, value,      \
                               sizeof((match)->mask->key.field));           \
                else                                                        \
                        memset((u8 *)&(match)->key->field, value,           \
                               sizeof((match)->key->field));                \
        } while (0)

static bool match_validate(const struct sw_flow_match *match,
                           u64 key_attrs, u64 mask_attrs, bool log)
{
        u64 key_expected = 1 << OVS_KEY_ATTR_ETHERNET;
        u64 mask_allowed = key_attrs;  /* At most allow all key attributes */

        /* The following mask attributes allowed only if they
         * pass the validation tests. */
        mask_allowed &= ~((1 << OVS_KEY_ATTR_IPV4)
                        | (1 << OVS_KEY_ATTR_IPV6)
                        | (1 << OVS_KEY_ATTR_TCP)
                        | (1 << OVS_KEY_ATTR_TCP_FLAGS)
                        | (1 << OVS_KEY_ATTR_UDP)
                        | (1 << OVS_KEY_ATTR_SCTP)
                        | (1 << OVS_KEY_ATTR_ICMP)
                        | (1 << OVS_KEY_ATTR_ICMPV6)
                        | (1 << OVS_KEY_ATTR_ARP)
                        | (1 << OVS_KEY_ATTR_ND)
                        | (1 << OVS_KEY_ATTR_MPLS));

        /* Always allowed mask fields. */
        mask_allowed |= ((1 << OVS_KEY_ATTR_TUNNEL)
                       | (1 << OVS_KEY_ATTR_IN_PORT)
                       | (1 << OVS_KEY_ATTR_ETHERTYPE));

        /* Check key attributes. */
        if (match->key->eth.type == htons(ETH_P_ARP)
                        || match->key->eth.type == htons(ETH_P_RARP)) {
                key_expected |= 1 << OVS_KEY_ATTR_ARP;
                if (match->mask && (match->mask->key.eth.type == htons(0xffff)))
                        mask_allowed |= 1 << OVS_KEY_ATTR_ARP;
        }

        if (eth_p_mpls(match->key->eth.type)) {
                key_expected |= 1 << OVS_KEY_ATTR_MPLS;
                if (match->mask && (match->mask->key.eth.type == htons(0xffff)))
                        mask_allowed |= 1 << OVS_KEY_ATTR_MPLS;
        }

        if (match->key->eth.type == htons(ETH_P_IP)) {
                key_expected |= 1 << OVS_KEY_ATTR_IPV4;
                if (match->mask && (match->mask->key.eth.type == htons(0xffff)))
                        mask_allowed |= 1 << OVS_KEY_ATTR_IPV4;

                if (match->key->ip.frag != OVS_FRAG_TYPE_LATER) {
                        if (match->key->ip.proto == IPPROTO_UDP) {
                                key_expected |= 1 << OVS_KEY_ATTR_UDP;
                                if (match->mask && (match->mask->key.ip.proto == 0xff))
                                        mask_allowed |= 1 << OVS_KEY_ATTR_UDP;
                        }

                        if (match->key->ip.proto == IPPROTO_SCTP) {
                                key_expected |= 1 << OVS_KEY_ATTR_SCTP;
                                if (match->mask && (match->mask->key.ip.proto == 0xff))
                                        mask_allowed |= 1 << OVS_KEY_ATTR_SCTP;
                        }

                        if (match->key->ip.proto == IPPROTO_TCP) {
                                key_expected |= 1 << OVS_KEY_ATTR_TCP;
                                key_expected |= 1 << OVS_KEY_ATTR_TCP_FLAGS;
                                if (match->mask && (match->mask->key.ip.proto == 0xff)) {
                                        mask_allowed |= 1 << OVS_KEY_ATTR_TCP;
                                        mask_allowed |= 1 << OVS_KEY_ATTR_TCP_FLAGS;
                                }
                        }

                        if (match->key->ip.proto == IPPROTO_ICMP) {
                                key_expected |= 1 << OVS_KEY_ATTR_ICMP;
                                if (match->mask && (match->mask->key.ip.proto == 0xff))
                                        mask_allowed |= 1 << OVS_KEY_ATTR_ICMP;
                        }
                }
        }

        if (match->key->eth.type == htons(ETH_P_IPV6)) {
                key_expected |= 1 << OVS_KEY_ATTR_IPV6;
                if (match->mask && (match->mask->key.eth.type == htons(0xffff)))
                        mask_allowed |= 1 << OVS_KEY_ATTR_IPV6;

                if (match->key->ip.frag != OVS_FRAG_TYPE_LATER) {
                        if (match->key->ip.proto == IPPROTO_UDP) {
                                key_expected |= 1 << OVS_KEY_ATTR_UDP;
                                if (match->mask && (match->mask->key.ip.proto == 0xff))
                                        mask_allowed |= 1 << OVS_KEY_ATTR_UDP;
                        }

                        if (match->key->ip.proto == IPPROTO_SCTP) {
                                key_expected |= 1 << OVS_KEY_ATTR_SCTP;
                                if (match->mask && (match->mask->key.ip.proto == 0xff))
                                        mask_allowed |= 1 << OVS_KEY_ATTR_SCTP;
                        }

                        if (match->key->ip.proto == IPPROTO_TCP) {
                                key_expected |= 1 << OVS_KEY_ATTR_TCP;
                                key_expected |= 1 << OVS_KEY_ATTR_TCP_FLAGS;
                                if (match->mask && (match->mask->key.ip.proto == 0xff)) {
                                        mask_allowed |= 1 << OVS_KEY_ATTR_TCP;
                                        mask_allowed |= 1 << OVS_KEY_ATTR_TCP_FLAGS;
                                }
                        }

                        if (match->key->ip.proto == IPPROTO_ICMPV6) {
                                key_expected |= 1 << OVS_KEY_ATTR_ICMPV6;
                                if (match->mask && (match->mask->key.ip.proto == 0xff))
                                        mask_allowed |= 1 << OVS_KEY_ATTR_ICMPV6;

                                if (match->key->tp.src ==
                                                htons(NDISC_NEIGHBOUR_SOLICITATION) ||
                                    match->key->tp.src == htons(NDISC_NEIGHBOUR_ADVERTISEMENT)) {
                                        key_expected |= 1 << OVS_KEY_ATTR_ND;
                                        if (match->mask && (match->mask->key.tp.src == htons(0xff)))
                                                mask_allowed |= 1 << OVS_KEY_ATTR_ND;
                                }
                        }
                }
        }

        if ((key_attrs & key_expected) != key_expected) {
                /* Key attributes check failed. */
                OVS_NLERR(log, "Missing key (keys=%llx, expected=%llx)",
                          (unsigned long long)key_attrs,
                          (unsigned long long)key_expected);
                return false;
        }

        if ((mask_attrs & mask_allowed) != mask_attrs) {
                /* Mask attributes check failed. */
                OVS_NLERR(log, "Unexpected mask (mask=%llx, allowed=%llx)",
                          (unsigned long long)mask_attrs,
                          (unsigned long long)mask_allowed);
                return false;
        }

        return true;
}

size_t ovs_tun_key_attr_size(void)
{
        /* Whenever adding new OVS_TUNNEL_KEY_ FIELDS, we should consider
         * updating this function.
         */
        return    nla_total_size_64bit(8) /* OVS_TUNNEL_KEY_ATTR_ID */
                + nla_total_size(16)   /* OVS_TUNNEL_KEY_ATTR_IPV[46]_SRC */
                + nla_total_size(16)   /* OVS_TUNNEL_KEY_ATTR_IPV[46]_DST */
                + nla_total_size(1)    /* OVS_TUNNEL_KEY_ATTR_TOS */
                + nla_total_size(1)    /* OVS_TUNNEL_KEY_ATTR_TTL */
                + nla_total_size(0)    /* OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT */
                + nla_total_size(0)    /* OVS_TUNNEL_KEY_ATTR_CSUM */
                + nla_total_size(0)    /* OVS_TUNNEL_KEY_ATTR_OAM */
                + nla_total_size(256)  /* OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS */
                /* OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS is mutually exclusive with
                 * OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS and covered by it.
                 */
                + nla_total_size(2)    /* OVS_TUNNEL_KEY_ATTR_TP_SRC */
                + nla_total_size(2);   /* OVS_TUNNEL_KEY_ATTR_TP_DST */
}

size_t ovs_key_attr_size(void)
{
        /* Whenever adding new OVS_KEY_ FIELDS, we should consider
         * updating this function.
         */
        BUILD_BUG_ON(OVS_KEY_ATTR_TUNNEL_INFO != 26);

        return    nla_total_size(4)   /* OVS_KEY_ATTR_PRIORITY */
                + nla_total_size(0)   /* OVS_KEY_ATTR_TUNNEL */
                  + ovs_tun_key_attr_size()
                + nla_total_size(4)   /* OVS_KEY_ATTR_IN_PORT */
                + nla_total_size(4)   /* OVS_KEY_ATTR_SKB_MARK */
                + nla_total_size(4)   /* OVS_KEY_ATTR_DP_HASH */
                + nla_total_size(4)   /* OVS_KEY_ATTR_RECIRC_ID */
                + nla_total_size(4)   /* OVS_KEY_ATTR_CT_STATE */
                + nla_total_size(2)   /* OVS_KEY_ATTR_CT_ZONE */
                + nla_total_size(4)   /* OVS_KEY_ATTR_CT_MARK */
                + nla_total_size(16)  /* OVS_KEY_ATTR_CT_LABELS */
                + nla_total_size(12)  /* OVS_KEY_ATTR_ETHERNET */
                + nla_total_size(2)   /* OVS_KEY_ATTR_ETHERTYPE */
                + nla_total_size(4)   /* OVS_KEY_ATTR_VLAN */
                + nla_total_size(0)   /* OVS_KEY_ATTR_ENCAP */
                + nla_total_size(2)   /* OVS_KEY_ATTR_ETHERTYPE */
                + nla_total_size(40)  /* OVS_KEY_ATTR_IPV6 */
                + nla_total_size(2)   /* OVS_KEY_ATTR_ICMPV6 */
                + nla_total_size(28); /* OVS_KEY_ATTR_ND */
}

static const struct ovs_len_tbl ovs_vxlan_ext_key_lens[OVS_VXLAN_EXT_MAX + 1] = {
        [OVS_VXLAN_EXT_GBP]         = { .len = sizeof(u32) },
};

static const struct ovs_len_tbl ovs_tunnel_key_lens[OVS_TUNNEL_KEY_ATTR_MAX + 1] = {
        [OVS_TUNNEL_KEY_ATTR_ID]            = { .len = sizeof(u64) },
        [OVS_TUNNEL_KEY_ATTR_IPV4_SRC]      = { .len = sizeof(u32) },
        [OVS_TUNNEL_KEY_ATTR_IPV4_DST]      = { .len = sizeof(u32) },
        [OVS_TUNNEL_KEY_ATTR_TOS]           = { .len = 1 },
        [OVS_TUNNEL_KEY_ATTR_TTL]           = { .len = 1 },
        [OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT] = { .len = 0 },
        [OVS_TUNNEL_KEY_ATTR_CSUM]          = { .len = 0 },
        [OVS_TUNNEL_KEY_ATTR_TP_SRC]        = { .len = sizeof(u16) },
        [OVS_TUNNEL_KEY_ATTR_TP_DST]        = { .len = sizeof(u16) },
        [OVS_TUNNEL_KEY_ATTR_OAM]           = { .len = 0 },
        [OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS]   = { .len = OVS_ATTR_VARIABLE },
        [OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS]    = { .len = OVS_ATTR_NESTED,
                                                .next = ovs_vxlan_ext_key_lens },
        [OVS_TUNNEL_KEY_ATTR_IPV6_SRC]      = { .len = sizeof(struct in6_addr) },
        [OVS_TUNNEL_KEY_ATTR_IPV6_DST]      = { .len = sizeof(struct in6_addr) },
};

/* The size of the argument for each %OVS_KEY_ATTR_* Netlink attribute.  */
static const struct ovs_len_tbl ovs_key_lens[OVS_KEY_ATTR_MAX + 1] = {
        [OVS_KEY_ATTR_ENCAP]     = { .len = OVS_ATTR_NESTED },
        [OVS_KEY_ATTR_PRIORITY]  = { .len = sizeof(u32) },
        [OVS_KEY_ATTR_IN_PORT]   = { .len = sizeof(u32) },
        [OVS_KEY_ATTR_SKB_MARK]  = { .len = sizeof(u32) },
        [OVS_KEY_ATTR_ETHERNET]  = { .len = sizeof(struct ovs_key_ethernet) },
        [OVS_KEY_ATTR_VLAN]      = { .len = sizeof(__be16) },
        [OVS_KEY_ATTR_ETHERTYPE] = { .len = sizeof(__be16) },
        [OVS_KEY_ATTR_IPV4]      = { .len = sizeof(struct ovs_key_ipv4) },
        [OVS_KEY_ATTR_IPV6]      = { .len = sizeof(struct ovs_key_ipv6) },
        [OVS_KEY_ATTR_TCP]       = { .len = sizeof(struct ovs_key_tcp) },
        [OVS_KEY_ATTR_TCP_FLAGS] = { .len = sizeof(__be16) },
        [OVS_KEY_ATTR_UDP]       = { .len = sizeof(struct ovs_key_udp) },
        [OVS_KEY_ATTR_SCTP]      = { .len = sizeof(struct ovs_key_sctp) },
        [OVS_KEY_ATTR_ICMP]      = { .len = sizeof(struct ovs_key_icmp) },
        [OVS_KEY_ATTR_ICMPV6]    = { .len = sizeof(struct ovs_key_icmpv6) },
        [OVS_KEY_ATTR_ARP]       = { .len = sizeof(struct ovs_key_arp) },
        [OVS_KEY_ATTR_ND]        = { .len = sizeof(struct ovs_key_nd) },
        [OVS_KEY_ATTR_RECIRC_ID] = { .len = sizeof(u32) },
        [OVS_KEY_ATTR_DP_HASH]   = { .len = sizeof(u32) },
        [OVS_KEY_ATTR_TUNNEL]    = { .len = OVS_ATTR_NESTED,
                                     .next = ovs_tunnel_key_lens, },
        [OVS_KEY_ATTR_MPLS]      = { .len = sizeof(struct ovs_key_mpls) },
        [OVS_KEY_ATTR_CT_STATE]  = { .len = sizeof(u32) },
        [OVS_KEY_ATTR_CT_ZONE]   = { .len = sizeof(u16) },
        [OVS_KEY_ATTR_CT_MARK]   = { .len = sizeof(u32) },
        [OVS_KEY_ATTR_CT_LABELS] = { .len = sizeof(struct ovs_key_ct_labels) },
};

static bool check_attr_len(unsigned int attr_len, unsigned int expected_len)
{
        return expected_len == attr_len ||
               expected_len == OVS_ATTR_NESTED ||
               expected_len == OVS_ATTR_VARIABLE;
}

static bool is_all_zero(const u8 *fp, size_t size)
{
        int i;

        if (!fp)
                return false;

        for (i = 0; i < size; i++)
                if (fp[i])
                        return false;

        return true;
}

static int __parse_flow_nlattrs(const struct nlattr *attr,
                                const struct nlattr *a[],
                                u64 *attrsp, bool log, bool nz)
{
        const struct nlattr *nla;
        u64 attrs;
        int rem;

        attrs = *attrsp;
        nla_for_each_nested(nla, attr, rem) {
                u16 type = nla_type(nla);
                int expected_len;

                if (type > OVS_KEY_ATTR_MAX) {
                        OVS_NLERR(log, "Key type %d is out of range max %d",
                                  type, OVS_KEY_ATTR_MAX);
                        return -EINVAL;
                }

                if (attrs & (1 << type)) {
                        OVS_NLERR(log, "Duplicate key (type %d).", type);
                        return -EINVAL;
                }

                expected_len = ovs_key_lens[type].len;
                if (!check_attr_len(nla_len(nla), expected_len)) {
                        OVS_NLERR(log, "Key %d has unexpected len %d expected %d",
                                  type, nla_len(nla), expected_len);
                        return -EINVAL;
                }

                if (!nz || !is_all_zero(nla_data(nla), expected_len)) {
                        attrs |= 1 << type;
                        a[type] = nla;
                }
        }
        if (rem) {
                OVS_NLERR(log, "Message has %d unknown bytes.", rem);
                return -EINVAL;
        }

        *attrsp = attrs;
        return 0;
}

static int parse_flow_mask_nlattrs(const struct nlattr *attr,
                                   const struct nlattr *a[], u64 *attrsp,
                                   bool log)
{
        return __parse_flow_nlattrs(attr, a, attrsp, log, true);
}

static int parse_flow_nlattrs(const struct nlattr *attr,
                              const struct nlattr *a[], u64 *attrsp,
                              bool log)
{
        return __parse_flow_nlattrs(attr, a, attrsp, log, false);
}

static int genev_tun_opt_from_nlattr(const struct nlattr *a,
                                     struct sw_flow_match *match, bool is_mask,
                                     bool log)
{
        unsigned long opt_key_offset;

        if (nla_len(a) > sizeof(match->key->tun_opts)) {
                OVS_NLERR(log, "Geneve option length err (len %d, max %zu).",
                          nla_len(a), sizeof(match->key->tun_opts));
                return -EINVAL;
        }

        if (nla_len(a) % 4 != 0) {
                OVS_NLERR(log, "Geneve opt len %d is not a multiple of 4.",
                          nla_len(a));
                return -EINVAL;
        }

        /* We need to record the length of the options passed
         * down, otherwise packets with the same format but
         * additional options will be silently matched.
         */
        if (!is_mask) {
                SW_FLOW_KEY_PUT(match, tun_opts_len, nla_len(a),
                                false);
        } else {
                /* This is somewhat unusual because it looks at
                 * both the key and mask while parsing the
                 * attributes (and by extension assumes the key
                 * is parsed first). Normally, we would verify
                 * that each is the correct length and that the
                 * attributes line up in the validate function.
                 * However, that is difficult because this is
                 * variable length and we won't have the
                 * information later.
                 */
                if (match->key->tun_opts_len != nla_len(a)) {
                        OVS_NLERR(log, "Geneve option len %d != mask len %d",
                                  match->key->tun_opts_len, nla_len(a));
                        return -EINVAL;
                }

                SW_FLOW_KEY_PUT(match, tun_opts_len, 0xff, true);
        }

        opt_key_offset = TUN_METADATA_OFFSET(nla_len(a));
        SW_FLOW_KEY_MEMCPY_OFFSET(match, opt_key_offset, nla_data(a),
                                  nla_len(a), is_mask);
        return 0;
}

static int vxlan_tun_opt_from_nlattr(const struct nlattr *attr,
                                     struct sw_flow_match *match, bool is_mask,
                                     bool log)
{
        struct nlattr *a;
        int rem;
        unsigned long opt_key_offset;
        struct vxlan_metadata opts;

        BUILD_BUG_ON(sizeof(opts) > sizeof(match->key->tun_opts));

        memset(&opts, 0, sizeof(opts));
        nla_for_each_nested(a, attr, rem) {
                int type = nla_type(a);

                if (type > OVS_VXLAN_EXT_MAX) {
                        OVS_NLERR(log, "VXLAN extension %d out of range max %d",
                                  type, OVS_VXLAN_EXT_MAX);
                        return -EINVAL;
                }

                if (!check_attr_len(nla_len(a),
                                    ovs_vxlan_ext_key_lens[type].len)) {
                        OVS_NLERR(log, "VXLAN extension %d has unexpected len %d expected %d",
                                  type, nla_len(a),
                                  ovs_vxlan_ext_key_lens[type].len);
                        return -EINVAL;
                }

                switch (type) {
                case OVS_VXLAN_EXT_GBP:
                        opts.gbp = nla_get_u32(a);
                        break;
                default:
                        OVS_NLERR(log, "Unknown VXLAN extension attribute %d",
                                  type);
                        return -EINVAL;
                }
        }
        if (rem) {
                OVS_NLERR(log, "VXLAN extension message has %d unknown bytes.",
                          rem);
                return -EINVAL;
        }

        if (!is_mask)
                SW_FLOW_KEY_PUT(match, tun_opts_len, sizeof(opts), false);
        else
                SW_FLOW_KEY_PUT(match, tun_opts_len, 0xff, true);

        opt_key_offset = TUN_METADATA_OFFSET(sizeof(opts));
        SW_FLOW_KEY_MEMCPY_OFFSET(match, opt_key_offset, &opts, sizeof(opts),
                                  is_mask);
        return 0;
}

static int ip_tun_from_nlattr(const struct nlattr *attr,
                              struct sw_flow_match *match, bool is_mask,
                              bool log)
{
        bool ttl = false, ipv4 = false, ipv6 = false;
        __be16 tun_flags = 0;
        int opts_type = 0;
        struct nlattr *a;
        int rem;

        nla_for_each_nested(a, attr, rem) {
                int type = nla_type(a);
                int err;

                if (type > OVS_TUNNEL_KEY_ATTR_MAX) {
                        OVS_NLERR(log, "Tunnel attr %d out of range max %d",
                                  type, OVS_TUNNEL_KEY_ATTR_MAX);
                        return -EINVAL;
                }

                if (!check_attr_len(nla_len(a),
                                    ovs_tunnel_key_lens[type].len)) {
                        OVS_NLERR(log, "Tunnel attr %d has unexpected len %d expected %d",
                                  type, nla_len(a), ovs_tunnel_key_lens[type].len);
                        return -EINVAL;
                }

                switch (type) {
                case OVS_TUNNEL_KEY_ATTR_ID:
                        SW_FLOW_KEY_PUT(match, tun_key.tun_id,
                                        nla_get_be64(a), is_mask);
                        tun_flags |= TUNNEL_KEY;
                        break;
                case OVS_TUNNEL_KEY_ATTR_IPV4_SRC:
                        SW_FLOW_KEY_PUT(match, tun_key.u.ipv4.src,
                                        nla_get_in_addr(a), is_mask);
                        ipv4 = true;
                        break;
                case OVS_TUNNEL_KEY_ATTR_IPV4_DST:
                        SW_FLOW_KEY_PUT(match, tun_key.u.ipv4.dst,
                                        nla_get_in_addr(a), is_mask);
                        ipv4 = true;
                        break;
                case OVS_TUNNEL_KEY_ATTR_IPV6_SRC:
                        SW_FLOW_KEY_PUT(match, tun_key.u.ipv6.dst,
                                        nla_get_in6_addr(a), is_mask);
                        ipv6 = true;
                        break;
                case OVS_TUNNEL_KEY_ATTR_IPV6_DST:
                        SW_FLOW_KEY_PUT(match, tun_key.u.ipv6.dst,
                                        nla_get_in6_addr(a), is_mask);
                        ipv6 = true;
                        break;
                case OVS_TUNNEL_KEY_ATTR_TOS:
                        SW_FLOW_KEY_PUT(match, tun_key.tos,
                                        nla_get_u8(a), is_mask);
                        break;
                case OVS_TUNNEL_KEY_ATTR_TTL:
                        SW_FLOW_KEY_PUT(match, tun_key.ttl,
                                        nla_get_u8(a), is_mask);
                        ttl = true;
                        break;
                case OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT:
                        tun_flags |= TUNNEL_DONT_FRAGMENT;
                        break;
                case OVS_TUNNEL_KEY_ATTR_CSUM:
                        tun_flags |= TUNNEL_CSUM;
                        break;
                case OVS_TUNNEL_KEY_ATTR_TP_SRC:
                        SW_FLOW_KEY_PUT(match, tun_key.tp_src,
                                        nla_get_be16(a), is_mask);
                        break;
                case OVS_TUNNEL_KEY_ATTR_TP_DST:
                        SW_FLOW_KEY_PUT(match, tun_key.tp_dst,
                                        nla_get_be16(a), is_mask);
                        break;
                case OVS_TUNNEL_KEY_ATTR_OAM:
                        tun_flags |= TUNNEL_OAM;
                        break;
                case OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS:
                        if (opts_type) {
                                OVS_NLERR(log, "Multiple metadata blocks provided");
                                return -EINVAL;
                        }

                        err = genev_tun_opt_from_nlattr(a, match, is_mask, log);
                        if (err)
                                return err;

                        tun_flags |= TUNNEL_GENEVE_OPT;
                        opts_type = type;
                        break;
                case OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS:
                        if (opts_type) {
                                OVS_NLERR(log, "Multiple metadata blocks provided");
                                return -EINVAL;
                        }

                        err = vxlan_tun_opt_from_nlattr(a, match, is_mask, log);
                        if (err)
                                return err;

                        tun_flags |= TUNNEL_VXLAN_OPT;
                        opts_type = type;
                        break;
                default:
                        OVS_NLERR(log, "Unknown IP tunnel attribute %d",
                                  type);
                        return -EINVAL;
                }
        }

        SW_FLOW_KEY_PUT(match, tun_key.tun_flags, tun_flags, is_mask);
        if (is_mask)
                SW_FLOW_KEY_MEMSET_FIELD(match, tun_proto, 0xff, true);
        else
                SW_FLOW_KEY_PUT(match, tun_proto, ipv6 ? AF_INET6 : AF_INET,
                                false);

        if (rem > 0) {
                OVS_NLERR(log, "IP tunnel attribute has %d unknown bytes.",
                          rem);
                return -EINVAL;
        }

        if (ipv4 && ipv6) {
                OVS_NLERR(log, "Mixed IPv4 and IPv6 tunnel attributes");
                return -EINVAL;
        }

        if (!is_mask) {
                if (!ipv4 && !ipv6) {
                        OVS_NLERR(log, "IP tunnel dst address not specified");
                        return -EINVAL;
                }
                if (ipv4 && !match->key->tun_key.u.ipv4.dst) {
                        OVS_NLERR(log, "IPv4 tunnel dst address is zero");
                        return -EINVAL;
                }
                if (ipv6 && ipv6_addr_any(&match->key->tun_key.u.ipv6.dst)) {
                        OVS_NLERR(log, "IPv6 tunnel dst address is zero");
                        return -EINVAL;
                }

                if (!ttl) {
                        OVS_NLERR(log, "IP tunnel TTL not specified.");
                        return -EINVAL;
                }
        }

        return opts_type;
}

static int vxlan_opt_to_nlattr(struct sk_buff *skb,
                               const void *tun_opts, int swkey_tun_opts_len)
{
        const struct vxlan_metadata *opts = tun_opts;
        struct nlattr *nla;

        nla = nla_nest_start(skb, OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS);
        if (!nla)
                return -EMSGSIZE;

        if (nla_put_u32(skb, OVS_VXLAN_EXT_GBP, opts->gbp) < 0)
                return -EMSGSIZE;

        nla_nest_end(skb, nla);
        return 0;
}

static int __ip_tun_to_nlattr(struct sk_buff *skb,
                              const struct ip_tunnel_key *output,
                              const void *tun_opts, int swkey_tun_opts_len,
                              unsigned short tun_proto)
{
        if (output->tun_flags & TUNNEL_KEY &&
            nla_put_be64(skb, OVS_TUNNEL_KEY_ATTR_ID, output->tun_id,
                         OVS_TUNNEL_KEY_ATTR_PAD))
                return -EMSGSIZE;
        switch (tun_proto) {
        case AF_INET:
                if (output->u.ipv4.src &&
                    nla_put_in_addr(skb, OVS_TUNNEL_KEY_ATTR_IPV4_SRC,
                                    output->u.ipv4.src))
                        return -EMSGSIZE;
                if (output->u.ipv4.dst &&
                    nla_put_in_addr(skb, OVS_TUNNEL_KEY_ATTR_IPV4_DST,
                                    output->u.ipv4.dst))
                        return -EMSGSIZE;
                break;
        case AF_INET6:
                if (!ipv6_addr_any(&output->u.ipv6.src) &&
                    nla_put_in6_addr(skb, OVS_TUNNEL_KEY_ATTR_IPV6_SRC,
                                     &output->u.ipv6.src))
                        return -EMSGSIZE;
                if (!ipv6_addr_any(&output->u.ipv6.dst) &&
                    nla_put_in6_addr(skb, OVS_TUNNEL_KEY_ATTR_IPV6_DST,
                                     &output->u.ipv6.dst))
                        return -EMSGSIZE;
                break;
        }
        if (output->tos &&
            nla_put_u8(skb, OVS_TUNNEL_KEY_ATTR_TOS, output->tos))
                return -EMSGSIZE;
        if (nla_put_u8(skb, OVS_TUNNEL_KEY_ATTR_TTL, output->ttl))
                return -EMSGSIZE;
        if ((output->tun_flags & TUNNEL_DONT_FRAGMENT) &&
            nla_put_flag(skb, OVS_TUNNEL_KEY_ATTR_DONT_FRAGMENT))
                return -EMSGSIZE;
        if ((output->tun_flags & TUNNEL_CSUM) &&
            nla_put_flag(skb, OVS_TUNNEL_KEY_ATTR_CSUM))
                return -EMSGSIZE;
        if (output->tp_src &&
            nla_put_be16(skb, OVS_TUNNEL_KEY_ATTR_TP_SRC, output->tp_src))
                return -EMSGSIZE;
        if (output->tp_dst &&
            nla_put_be16(skb, OVS_TUNNEL_KEY_ATTR_TP_DST, output->tp_dst))
                return -EMSGSIZE;
        if ((output->tun_flags & TUNNEL_OAM) &&
            nla_put_flag(skb, OVS_TUNNEL_KEY_ATTR_OAM))
                return -EMSGSIZE;
        if (swkey_tun_opts_len) {
                if (output->tun_flags & TUNNEL_GENEVE_OPT &&
                    nla_put(skb, OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS,
                            swkey_tun_opts_len, tun_opts))
                        return -EMSGSIZE;
                else if (output->tun_flags & TUNNEL_VXLAN_OPT &&
                         vxlan_opt_to_nlattr(skb, tun_opts, swkey_tun_opts_len))
                        return -EMSGSIZE;
        }

        return 0;
}

static int ip_tun_to_nlattr(struct sk_buff *skb,
                            const struct ip_tunnel_key *output,
                            const void *tun_opts, int swkey_tun_opts_len,
                            unsigned short tun_proto)
{
        struct nlattr *nla;
        int err;

        nla = nla_nest_start(skb, OVS_KEY_ATTR_TUNNEL);
        if (!nla)
                return -EMSGSIZE;

        err = __ip_tun_to_nlattr(skb, output, tun_opts, swkey_tun_opts_len,
                                 tun_proto);
        if (err)
                return err;

        nla_nest_end(skb, nla);
        return 0;
}

int ovs_nla_put_tunnel_info(struct sk_buff *skb,
                            struct ip_tunnel_info *tun_info)
{
        return __ip_tun_to_nlattr(skb, &tun_info->key,
                                  ip_tunnel_info_opts(tun_info),
                                  tun_info->options_len,
                                  ip_tunnel_info_af(tun_info));
}

static int metadata_from_nlattrs(struct net *net, struct sw_flow_match *match,
                                 u64 *attrs, const struct nlattr **a,
                                 bool is_mask, bool log)
{
        if (*attrs & (1 << OVS_KEY_ATTR_DP_HASH)) {
                u32 hash_val = nla_get_u32(a[OVS_KEY_ATTR_DP_HASH]);

                SW_FLOW_KEY_PUT(match, ovs_flow_hash, hash_val, is_mask);
                *attrs &= ~(1 << OVS_KEY_ATTR_DP_HASH);
        }

        if (*attrs & (1 << OVS_KEY_ATTR_RECIRC_ID)) {
                u32 recirc_id = nla_get_u32(a[OVS_KEY_ATTR_RECIRC_ID]);

                SW_FLOW_KEY_PUT(match, recirc_id, recirc_id, is_mask);
                *attrs &= ~(1 << OVS_KEY_ATTR_RECIRC_ID);
        }

        if (*attrs & (1 << OVS_KEY_ATTR_PRIORITY)) {
                SW_FLOW_KEY_PUT(match, phy.priority,
                          nla_get_u32(a[OVS_KEY_ATTR_PRIORITY]), is_mask);
                *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 (is_mask) {
                        in_port = 0xffffffff; /* Always exact match in_port. */
                } else if (in_port >= DP_MAX_PORTS) {
                        OVS_NLERR(log, "Port %d exceeds max allowable %d",
                                  in_port, DP_MAX_PORTS);
                        return -EINVAL;
                }

                SW_FLOW_KEY_PUT(match, phy.in_port, in_port, is_mask);
                *attrs &= ~(1 << OVS_KEY_ATTR_IN_PORT);
        } else if (!is_mask) {
                SW_FLOW_KEY_PUT(match, phy.in_port, DP_MAX_PORTS, is_mask);
        }

        if (*attrs & (1 << OVS_KEY_ATTR_SKB_MARK)) {
                uint32_t mark = nla_get_u32(a[OVS_KEY_ATTR_SKB_MARK]);

                SW_FLOW_KEY_PUT(match, phy.skb_mark, mark, is_mask);
                *attrs &= ~(1 << OVS_KEY_ATTR_SKB_MARK);
        }
        if (*attrs & (1 << OVS_KEY_ATTR_TUNNEL)) {
                if (ip_tun_from_nlattr(a[OVS_KEY_ATTR_TUNNEL], match,
                                       is_mask, log) < 0)
                        return -EINVAL;
                *attrs &= ~(1 << OVS_KEY_ATTR_TUNNEL);
        }

        if (*attrs & (1 << OVS_KEY_ATTR_CT_STATE) &&
            ovs_ct_verify(net, OVS_KEY_ATTR_CT_STATE)) {
                u32 ct_state = nla_get_u32(a[OVS_KEY_ATTR_CT_STATE]);

                if (ct_state & ~CT_SUPPORTED_MASK) {
                        OVS_NLERR(log, "ct_state flags %08x unsupported",
                                  ct_state);
                        return -EINVAL;
                }

                SW_FLOW_KEY_PUT(match, ct.state, ct_state, is_mask);
                *attrs &= ~(1ULL << OVS_KEY_ATTR_CT_STATE);
        }
        if (*attrs & (1 << OVS_KEY_ATTR_CT_ZONE) &&
            ovs_ct_verify(net, OVS_KEY_ATTR_CT_ZONE)) {
                u16 ct_zone = nla_get_u16(a[OVS_KEY_ATTR_CT_ZONE]);

                SW_FLOW_KEY_PUT(match, ct.zone, ct_zone, is_mask);
                *attrs &= ~(1ULL << OVS_KEY_ATTR_CT_ZONE);
        }
        if (*attrs & (1 << OVS_KEY_ATTR_CT_MARK) &&
            ovs_ct_verify(net, OVS_KEY_ATTR_CT_MARK)) {
                u32 mark = nla_get_u32(a[OVS_KEY_ATTR_CT_MARK]);

                SW_FLOW_KEY_PUT(match, ct.mark, mark, is_mask);
                *attrs &= ~(1ULL << OVS_KEY_ATTR_CT_MARK);
        }
        if (*attrs & (1 << OVS_KEY_ATTR_CT_LABELS) &&
            ovs_ct_verify(net, OVS_KEY_ATTR_CT_LABELS)) {
                const struct ovs_key_ct_labels *cl;

                cl = nla_data(a[OVS_KEY_ATTR_CT_LABELS]);
                SW_FLOW_KEY_MEMCPY(match, ct.labels, cl->ct_labels,
                                   sizeof(*cl), is_mask);
                *attrs &= ~(1ULL << OVS_KEY_ATTR_CT_LABELS);
        }
        return 0;
}

static int ovs_key_from_nlattrs(struct net *net, struct sw_flow_match *match,
                                u64 attrs, const struct nlattr **a,
                                bool is_mask, bool log)
{
        int err;

        err = metadata_from_nlattrs(net, match, &attrs, a, is_mask, log);
        if (err)
                return err;

        if (attrs & (1 << OVS_KEY_ATTR_ETHERNET)) {
                const struct ovs_key_ethernet *eth_key;

                eth_key = nla_data(a[OVS_KEY_ATTR_ETHERNET]);
                SW_FLOW_KEY_MEMCPY(match, eth.src,
                                eth_key->eth_src, ETH_ALEN, is_mask);
                SW_FLOW_KEY_MEMCPY(match, eth.dst,
                                eth_key->eth_dst, ETH_ALEN, is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_ETHERNET);
        }

        if (attrs & (1 << OVS_KEY_ATTR_VLAN)) {
                __be16 tci;

                tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
                if (!(tci & htons(VLAN_TAG_PRESENT))) {
                        if (is_mask)
                                OVS_NLERR(log, "VLAN TCI mask does not have exact match for VLAN_TAG_PRESENT bit.");
                        else
                                OVS_NLERR(log, "VLAN TCI does not have VLAN_TAG_PRESENT bit set.");

                        return -EINVAL;
                }

                SW_FLOW_KEY_PUT(match, eth.tci, tci, is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_VLAN);
        }

        if (attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) {
                __be16 eth_type;

                eth_type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);
                if (is_mask) {
                        /* Always exact match EtherType. */
                        eth_type = htons(0xffff);
                } else if (!eth_proto_is_802_3(eth_type)) {
                        OVS_NLERR(log, "EtherType %x is less than min %x",
                                  ntohs(eth_type), ETH_P_802_3_MIN);
                        return -EINVAL;
                }

                SW_FLOW_KEY_PUT(match, eth.type, eth_type, is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
        } else if (!is_mask) {
                SW_FLOW_KEY_PUT(match, eth.type, htons(ETH_P_802_2), is_mask);
        }

        if (attrs & (1 << OVS_KEY_ATTR_IPV4)) {
                const struct ovs_key_ipv4 *ipv4_key;

                ipv4_key = nla_data(a[OVS_KEY_ATTR_IPV4]);
                if (!is_mask && ipv4_key->ipv4_frag > OVS_FRAG_TYPE_MAX) {
                        OVS_NLERR(log, "IPv4 frag type %d is out of range max %d",
                                  ipv4_key->ipv4_frag, OVS_FRAG_TYPE_MAX);
                        return -EINVAL;
                }
                SW_FLOW_KEY_PUT(match, ip.proto,
                                ipv4_key->ipv4_proto, is_mask);
                SW_FLOW_KEY_PUT(match, ip.tos,
                                ipv4_key->ipv4_tos, is_mask);
                SW_FLOW_KEY_PUT(match, ip.ttl,
                                ipv4_key->ipv4_ttl, is_mask);
                SW_FLOW_KEY_PUT(match, ip.frag,
                                ipv4_key->ipv4_frag, is_mask);
                SW_FLOW_KEY_PUT(match, ipv4.addr.src,
                                ipv4_key->ipv4_src, is_mask);
                SW_FLOW_KEY_PUT(match, ipv4.addr.dst,
                                ipv4_key->ipv4_dst, is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_IPV4);
        }

        if (attrs & (1 << OVS_KEY_ATTR_IPV6)) {
                const struct ovs_key_ipv6 *ipv6_key;

                ipv6_key = nla_data(a[OVS_KEY_ATTR_IPV6]);
                if (!is_mask && ipv6_key->ipv6_frag > OVS_FRAG_TYPE_MAX) {
                        OVS_NLERR(log, "IPv6 frag type %d is out of range max %d",
                                  ipv6_key->ipv6_frag, OVS_FRAG_TYPE_MAX);
                        return -EINVAL;
                }

                if (!is_mask && ipv6_key->ipv6_label & htonl(0xFFF00000)) {
                        OVS_NLERR(log, "IPv6 flow label %x is out of range (max=%x).\n",
                                  ntohl(ipv6_key->ipv6_label), (1 << 20) - 1);
                        return -EINVAL;
                }

                SW_FLOW_KEY_PUT(match, ipv6.label,
                                ipv6_key->ipv6_label, is_mask);
                SW_FLOW_KEY_PUT(match, ip.proto,
                                ipv6_key->ipv6_proto, is_mask);
                SW_FLOW_KEY_PUT(match, ip.tos,
                                ipv6_key->ipv6_tclass, is_mask);
                SW_FLOW_KEY_PUT(match, ip.ttl,
                                ipv6_key->ipv6_hlimit, is_mask);
                SW_FLOW_KEY_PUT(match, ip.frag,
                                ipv6_key->ipv6_frag, is_mask);
                SW_FLOW_KEY_MEMCPY(match, ipv6.addr.src,
                                ipv6_key->ipv6_src,
                                sizeof(match->key->ipv6.addr.src),
                                is_mask);
                SW_FLOW_KEY_MEMCPY(match, ipv6.addr.dst,
                                ipv6_key->ipv6_dst,
                                sizeof(match->key->ipv6.addr.dst),
                                is_mask);

                attrs &= ~(1 << OVS_KEY_ATTR_IPV6);
        }

        if (attrs & (1 << OVS_KEY_ATTR_ARP)) {
                const struct ovs_key_arp *arp_key;

                arp_key = nla_data(a[OVS_KEY_ATTR_ARP]);
                if (!is_mask && (arp_key->arp_op & htons(0xff00))) {
                        OVS_NLERR(log, "Unknown ARP opcode (opcode=%d).",
                                  arp_key->arp_op);
                        return -EINVAL;
                }

                SW_FLOW_KEY_PUT(match, ipv4.addr.src,
                                arp_key->arp_sip, is_mask);
                SW_FLOW_KEY_PUT(match, ipv4.addr.dst,
                        arp_key->arp_tip, is_mask);
                SW_FLOW_KEY_PUT(match, ip.proto,
                                ntohs(arp_key->arp_op), is_mask);
                SW_FLOW_KEY_MEMCPY(match, ipv4.arp.sha,
                                arp_key->arp_sha, ETH_ALEN, is_mask);
                SW_FLOW_KEY_MEMCPY(match, ipv4.arp.tha,
                                arp_key->arp_tha, ETH_ALEN, is_mask);

                attrs &= ~(1 << OVS_KEY_ATTR_ARP);
        }

        if (attrs & (1 << OVS_KEY_ATTR_MPLS)) {
                const struct ovs_key_mpls *mpls_key;

                mpls_key = nla_data(a[OVS_KEY_ATTR_MPLS]);
                SW_FLOW_KEY_PUT(match, mpls.top_lse,
                                mpls_key->mpls_lse, is_mask);

                attrs &= ~(1 << OVS_KEY_ATTR_MPLS);
         }

        if (attrs & (1 << OVS_KEY_ATTR_TCP)) {
                const struct ovs_key_tcp *tcp_key;

                tcp_key = nla_data(a[OVS_KEY_ATTR_TCP]);
                SW_FLOW_KEY_PUT(match, tp.src, tcp_key->tcp_src, is_mask);
                SW_FLOW_KEY_PUT(match, tp.dst, tcp_key->tcp_dst, is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_TCP);
        }

        if (attrs & (1 << OVS_KEY_ATTR_TCP_FLAGS)) {
                SW_FLOW_KEY_PUT(match, tp.flags,
                                nla_get_be16(a[OVS_KEY_ATTR_TCP_FLAGS]),
                                is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_TCP_FLAGS);
        }

        if (attrs & (1 << OVS_KEY_ATTR_UDP)) {
                const struct ovs_key_udp *udp_key;

                udp_key = nla_data(a[OVS_KEY_ATTR_UDP]);
                SW_FLOW_KEY_PUT(match, tp.src, udp_key->udp_src, is_mask);
                SW_FLOW_KEY_PUT(match, tp.dst, udp_key->udp_dst, is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_UDP);
        }

        if (attrs & (1 << OVS_KEY_ATTR_SCTP)) {
                const struct ovs_key_sctp *sctp_key;

                sctp_key = nla_data(a[OVS_KEY_ATTR_SCTP]);
                SW_FLOW_KEY_PUT(match, tp.src, sctp_key->sctp_src, is_mask);
                SW_FLOW_KEY_PUT(match, tp.dst, sctp_key->sctp_dst, is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_SCTP);
        }

        if (attrs & (1 << OVS_KEY_ATTR_ICMP)) {
                const struct ovs_key_icmp *icmp_key;

                icmp_key = nla_data(a[OVS_KEY_ATTR_ICMP]);
                SW_FLOW_KEY_PUT(match, tp.src,
                                htons(icmp_key->icmp_type), is_mask);
                SW_FLOW_KEY_PUT(match, tp.dst,
                                htons(icmp_key->icmp_code), is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_ICMP);
        }

        if (attrs & (1 << OVS_KEY_ATTR_ICMPV6)) {
                const struct ovs_key_icmpv6 *icmpv6_key;

                icmpv6_key = nla_data(a[OVS_KEY_ATTR_ICMPV6]);
                SW_FLOW_KEY_PUT(match, tp.src,
                                htons(icmpv6_key->icmpv6_type), is_mask);
                SW_FLOW_KEY_PUT(match, tp.dst,
                                htons(icmpv6_key->icmpv6_code), is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_ICMPV6);
        }

        if (attrs & (1 << OVS_KEY_ATTR_ND)) {
                const struct ovs_key_nd *nd_key;

                nd_key = nla_data(a[OVS_KEY_ATTR_ND]);
                SW_FLOW_KEY_MEMCPY(match, ipv6.nd.target,
                        nd_key->nd_target,
                        sizeof(match->key->ipv6.nd.target),
                        is_mask);
                SW_FLOW_KEY_MEMCPY(match, ipv6.nd.sll,
                        nd_key->nd_sll, ETH_ALEN, is_mask);
                SW_FLOW_KEY_MEMCPY(match, ipv6.nd.tll,
                                nd_key->nd_tll, ETH_ALEN, is_mask);
                attrs &= ~(1 << OVS_KEY_ATTR_ND);
        }

        if (attrs != 0) {
                OVS_NLERR(log, "Unknown key attributes %llx",
                          (unsigned long long)attrs);
                return -EINVAL;
        }

        return 0;
}

static void nlattr_set(struct nlattr *attr, u8 val,
                       const struct ovs_len_tbl *tbl)
{
        struct nlattr *nla;
        int rem;

        /* The nlattr stream should already have been validated */
        nla_for_each_nested(nla, attr, rem) {
                if (tbl[nla_type(nla)].len == OVS_ATTR_NESTED) {
                        if (tbl[nla_type(nla)].next)
                                tbl = tbl[nla_type(nla)].next;
                        nlattr_set(nla, val, tbl);
                } else {
                        memset(nla_data(nla), val, nla_len(nla));
                }

                if (nla_type(nla) == OVS_KEY_ATTR_CT_STATE)
                        *(u32 *)nla_data(nla) &= CT_SUPPORTED_MASK;
        }
}

static void mask_set_nlattr(struct nlattr *attr, u8 val)
{
        nlattr_set(attr, val, ovs_key_lens);
}

/**
 * ovs_nla_get_match - parses Netlink attributes into a flow key and
 * mask. In case the 'mask' is NULL, the flow is treated as exact match
 * flow. Otherwise, it is treated as a wildcarded flow, except the mask
 * does not include any don't care bit.
 * @net: Used to determine per-namespace field support.
 * @match: receives the extracted flow match information.
 * @key: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
 * sequence. The fields should of the packet that triggered the creation
 * of this flow.
 * @mask: Optional. Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink
 * attribute specifies the mask field of the wildcarded flow.
 * @log: Boolean to allow kernel error logging.  Normally true, but when
 * probing for feature compatibility this should be passed in as false to
 * suppress unnecessary error logging.
 */
int ovs_nla_get_match(struct net *net, struct sw_flow_match *match,
                      const struct nlattr *nla_key,
                      const struct nlattr *nla_mask,
                      bool log)
{
        const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
        const struct nlattr *encap;
        struct nlattr *newmask = NULL;
        u64 key_attrs = 0;
        u64 mask_attrs = 0;
        bool encap_valid = false;
        int err;

        err = parse_flow_nlattrs(nla_key, a, &key_attrs, log);
        if (err)
                return err;

        if ((key_attrs & (1 << OVS_KEY_ATTR_ETHERNET)) &&
            (key_attrs & (1 << OVS_KEY_ATTR_ETHERTYPE)) &&
            (nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]) == htons(ETH_P_8021Q))) {
                __be16 tci;

                if (!((key_attrs & (1 << OVS_KEY_ATTR_VLAN)) &&
                      (key_attrs & (1 << OVS_KEY_ATTR_ENCAP)))) {
                        OVS_NLERR(log, "Invalid Vlan frame.");
                        return -EINVAL;
                }

                key_attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
                tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);
                encap = a[OVS_KEY_ATTR_ENCAP];
                key_attrs &= ~(1 << OVS_KEY_ATTR_ENCAP);
                encap_valid = true;

                if (tci & htons(VLAN_TAG_PRESENT)) {
                        err = parse_flow_nlattrs(encap, a, &key_attrs, log);
                        if (err)
                                return err;
                } else if (!tci) {
                        /* Corner case for truncated 802.1Q header. */
                        if (nla_len(encap)) {
                                OVS_NLERR(log, "Truncated 802.1Q header has non-zero encap attribute.");
                                return -EINVAL;
                        }
                } else {
                        OVS_NLERR(log, "Encap attr is set for non-VLAN frame");
                        return  -EINVAL;
                }
        }

        err = ovs_key_from_nlattrs(net, match, key_attrs, a, false, log);
        if (err)
                return err;

        if (match->mask) {
                if (!nla_mask) {
                        /* Create an exact match mask. We need to set to 0xff
                         * all the 'match->mask' fields that have been touched
                         * in 'match->key'. We cannot simply memset
                         * 'match->mask', because padding bytes and fields not
                         * specified in 'match->key' should be left to 0.
                         * Instead, we use a stream of netlink attributes,
                         * copied from 'key' and set to 0xff.
                         * ovs_key_from_nlattrs() will take care of filling
                         * 'match->mask' appropriately.
                         */
                        newmask = kmemdup(nla_key,
                                          nla_total_size(nla_len(nla_key)),
                                          GFP_KERNEL);
                        if (!newmask)
                                return -ENOMEM;

                        mask_set_nlattr(newmask, 0xff);

                        /* The userspace does not send tunnel attributes that
                         * are 0, but we should not wildcard them nonetheless.
                         */
                        if (match->key->tun_proto)
                                SW_FLOW_KEY_MEMSET_FIELD(match, tun_key,
                                                         0xff, true);

                        nla_mask = newmask;
                }

                err = parse_flow_mask_nlattrs(nla_mask, a, &mask_attrs, log);
                if (err)
                        goto free_newmask;

                /* Always match on tci. */
                SW_FLOW_KEY_PUT(match, eth.tci, htons(0xffff), true);

                if (mask_attrs & 1 << OVS_KEY_ATTR_ENCAP) {
                        __be16 eth_type = 0;
                        __be16 tci = 0;

                        if (!encap_valid) {
                                OVS_NLERR(log, "Encap mask attribute is set for non-VLAN frame.");
                                err = -EINVAL;
                                goto free_newmask;
                        }

                        mask_attrs &= ~(1 << OVS_KEY_ATTR_ENCAP);
                        if (a[OVS_KEY_ATTR_ETHERTYPE])
                                eth_type = nla_get_be16(a[OVS_KEY_ATTR_ETHERTYPE]);

                        if (eth_type == htons(0xffff)) {
                                mask_attrs &= ~(1 << OVS_KEY_ATTR_ETHERTYPE);
                                encap = a[OVS_KEY_ATTR_ENCAP];
                                err = parse_flow_mask_nlattrs(encap, a,
                                                              &mask_attrs, log);
                                if (err)
                                        goto free_newmask;
                        } else {
                                OVS_NLERR(log, "VLAN frames must have an exact match on the TPID (mask=%x).",
                                          ntohs(eth_type));
                                err = -EINVAL;
                                goto free_newmask;
                        }

                        if (a[OVS_KEY_ATTR_VLAN])
                                tci = nla_get_be16(a[OVS_KEY_ATTR_VLAN]);

                        if (!(tci & htons(VLAN_TAG_PRESENT))) {
                                OVS_NLERR(log, "VLAN tag present bit must have an exact match (tci_mask=%x).",
                                          ntohs(tci));
                                err = -EINVAL;
                                goto free_newmask;
                        }
                }

                err = ovs_key_from_nlattrs(net, match, mask_attrs, a, true,
                                           log);
                if (err)
                        goto free_newmask;
        }

        if (!match_validate(match, key_attrs, mask_attrs, log))
                err = -EINVAL;

free_newmask:
        kfree(newmask);
        return err;
}

static size_t get_ufid_len(const struct nlattr *attr, bool log)
{
        size_t len;

        if (!attr)
                return 0;

        len = nla_len(attr);
        if (len < 1 || len > MAX_UFID_LENGTH) {
                OVS_NLERR(log, "ufid size %u bytes exceeds the range (1, %d)",
                          nla_len(attr), MAX_UFID_LENGTH);
                return 0;
        }

        return len;
}

/* Initializes 'flow->ufid', returning true if 'attr' contains a valid UFID,
 * or false otherwise.
 */
bool ovs_nla_get_ufid(struct sw_flow_id *sfid, const struct nlattr *attr,
                      bool log)
{
        sfid->ufid_len = get_ufid_len(attr, log);
        if (sfid->ufid_len)
                memcpy(sfid->ufid, nla_data(attr), sfid->ufid_len);

        return sfid->ufid_len;
}

int ovs_nla_get_identifier(struct sw_flow_id *sfid, const struct nlattr *ufid,
                           const struct sw_flow_key *key, bool log)
{
        struct sw_flow_key *new_key;

        if (ovs_nla_get_ufid(sfid, ufid, log))
                return 0;

        /* If UFID was not provided, use unmasked key. */
        new_key = kmalloc(sizeof(*new_key), GFP_KERNEL);
        if (!new_key)
                return -ENOMEM;
        memcpy(new_key, key, sizeof(*key));
        sfid->unmasked_key = new_key;

        return 0;
}

u32 ovs_nla_get_ufid_flags(const struct nlattr *attr)
{
        return attr ? nla_get_u32(attr) : 0;
}

/**
 * ovs_nla_get_flow_metadata - parses Netlink attributes into a flow key.
 * @key: Receives extracted in_port, priority, tun_key and skb_mark.
 * @attr: Netlink attribute holding nested %OVS_KEY_ATTR_* Netlink attribute
 * sequence.
 * @log: Boolean to allow kernel error logging.  Normally true, but when
 * probing for feature compatibility this should be passed in as false to
 * suppress unnecessary error logging.
 *
 * 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_nla_get_flow_metadata(struct net *net, const struct nlattr *attr,
                              struct sw_flow_key *key,
                              bool log)
{
        const struct nlattr *a[OVS_KEY_ATTR_MAX + 1];
        struct sw_flow_match match;
        u64 attrs = 0;
        int err;

        err = parse_flow_nlattrs(attr, a, &attrs, log);
        if (err)
                return -EINVAL;

        memset(&match, 0, sizeof(match));
        match.key = key;

        memset(&key->ct, 0, sizeof(key->ct));
        key->phy.in_port = DP_MAX_PORTS;

        return metadata_from_nlattrs(net, &match, &attrs, a, false, log);
}

static int __ovs_nla_put_key(const struct sw_flow_key *swkey,
                             const struct sw_flow_key *output, bool is_mask,
                             struct sk_buff *skb)
{
        struct ovs_key_ethernet *eth_key;
        struct nlattr *nla, *encap;

        if (nla_put_u32(skb, OVS_KEY_ATTR_RECIRC_ID, output->recirc_id))
                goto nla_put_failure;

        if (nla_put_u32(skb, OVS_KEY_ATTR_DP_HASH, output->ovs_flow_hash))
                goto nla_put_failure;

        if (nla_put_u32(skb, OVS_KEY_ATTR_PRIORITY, output->phy.priority))
                goto nla_put_failure;

        if ((swkey->tun_proto || is_mask)) {
                const void *opts = NULL;

                if (output->tun_key.tun_flags & TUNNEL_OPTIONS_PRESENT)
                        opts = TUN_METADATA_OPTS(output, swkey->tun_opts_len);

                if (ip_tun_to_nlattr(skb, &output->tun_key, opts,
                                     swkey->tun_opts_len, swkey->tun_proto))
                        goto nla_put_failure;
        }

        if (swkey->phy.in_port == DP_MAX_PORTS) {
                if (is_mask && (output->phy.in_port == 0xffff))
                        if (nla_put_u32(skb, OVS_KEY_ATTR_IN_PORT, 0xffffffff))
                                goto nla_put_failure;
        } else {
                u16 upper_u16;
                upper_u16 = !is_mask ? 0 : 0xffff;

                if (nla_put_u32(skb, OVS_KEY_ATTR_IN_PORT,
                                (upper_u16 << 16) | output->phy.in_port))
                        goto nla_put_failure;
        }

        if (nla_put_u32(skb, OVS_KEY_ATTR_SKB_MARK, output->phy.skb_mark))
                goto nla_put_failure;

        if (ovs_ct_put_key(output, skb))
                goto nla_put_failure;

        nla = nla_reserve(skb, OVS_KEY_ATTR_ETHERNET, sizeof(*eth_key));
        if (!nla)
                goto nla_put_failure;

        eth_key = nla_data(nla);
        ether_addr_copy(eth_key->eth_src, output->eth.src);
        ether_addr_copy(eth_key->eth_dst, output->eth.dst);

        if (swkey->eth.tci || swkey->eth.type == htons(ETH_P_8021Q)) {
                __be16 eth_type;
                eth_type = !is_mask ? htons(ETH_P_8021Q) : htons(0xffff);
                if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, eth_type) ||
                    nla_put_be16(skb, OVS_KEY_ATTR_VLAN, output->eth.tci))
                        goto nla_put_failure;
                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)) {
                /*
                 * Ethertype 802.2 is represented in the netlink with omitted
                 * OVS_KEY_ATTR_ETHERTYPE in the flow key attribute, and
                 * 0xffff in the mask attribute.  Ethertype can also
                 * be wildcarded.
                 */
                if (is_mask && output->eth.type)
                        if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE,
                                                output->eth.type))
                                goto nla_put_failure;
                goto unencap;
        }

        if (nla_put_be16(skb, OVS_KEY_ATTR_ETHERTYPE, output->eth.type))
                goto nla_put_failure;

        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 = output->ipv4.addr.src;
                ipv4_key->ipv4_dst = output->ipv4.addr.dst;
                ipv4_key->ipv4_proto = output->ip.proto;
                ipv4_key->ipv4_tos = output->ip.tos;
                ipv4_key->ipv4_ttl = output->ip.ttl;
                ipv4_key->ipv4_frag = output->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, &output->ipv6.addr.src,
                                sizeof(ipv6_key->ipv6_src));
                memcpy(ipv6_key->ipv6_dst, &output->ipv6.addr.dst,
                                sizeof(ipv6_key->ipv6_dst));
                ipv6_key->ipv6_label = output->ipv6.label;
                ipv6_key->ipv6_proto = output->ip.proto;
                ipv6_key->ipv6_tclass = output->ip.tos;
                ipv6_key->ipv6_hlimit = output->ip.ttl;
                ipv6_key->ipv6_frag = output->ip.frag;
        } else if (swkey->eth.type == htons(ETH_P_ARP) ||
                   swkey->eth.type == htons(ETH_P_RARP)) {
                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 = output->ipv4.addr.src;
                arp_key->arp_tip = output->ipv4.addr.dst;
                arp_key->arp_op = htons(output->ip.proto);
                ether_addr_copy(arp_key->arp_sha, output->ipv4.arp.sha);
                ether_addr_copy(arp_key->arp_tha, output->ipv4.arp.tha);
        } else if (eth_p_mpls(swkey->eth.type)) {
                struct ovs_key_mpls *mpls_key;

                nla = nla_reserve(skb, OVS_KEY_ATTR_MPLS, sizeof(*mpls_key));
                if (!nla)
                        goto nla_put_failure;
                mpls_key = nla_data(nla);
                mpls_key->mpls_lse = output->mpls.top_lse;
        }

        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);
                        tcp_key->tcp_src = output->tp.src;
                        tcp_key->tcp_dst = output->tp.dst;
                        if (nla_put_be16(skb, OVS_KEY_ATTR_TCP_FLAGS,
                                         output->tp.flags))
                                goto nla_put_failure;
                } 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);
                        udp_key->udp_src = output->tp.src;
                        udp_key->udp_dst = output->tp.dst;
                } else if (swkey->ip.proto == IPPROTO_SCTP) {
                        struct ovs_key_sctp *sctp_key;

                        nla = nla_reserve(skb, OVS_KEY_ATTR_SCTP, sizeof(*sctp_key));
                        if (!nla)
                                goto nla_put_failure;
                        sctp_key = nla_data(nla);
                        sctp_key->sctp_src = output->tp.src;
                        sctp_key->sctp_dst = output->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(output->tp.src);
                        icmp_key->icmp_code = ntohs(output->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(output->tp.src);
                        icmpv6_key->icmpv6_code = ntohs(output->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, &output->ipv6.nd.target,
                                                        sizeof(nd_key->nd_target));
                                ether_addr_copy(nd_key->nd_sll, output->ipv6.nd.sll);
                                ether_addr_copy(nd_key->nd_tll, output->ipv6.nd.tll);
                        }
                }
        }

unencap:
        if (encap)
                nla_nest_end(skb, encap);

        return 0;

nla_put_failure:
        return -EMSGSIZE;
}

int ovs_nla_put_key(const struct sw_flow_key *swkey,
                    const struct sw_flow_key *output, int attr, bool is_mask,
                    struct sk_buff *skb)
{
        int err;
        struct nlattr *nla;

        nla = nla_nest_start(skb, attr);
        if (!nla)
                return -EMSGSIZE;
        err = __ovs_nla_put_key(swkey, output, is_mask, skb);
        if (err)
                return err;
        nla_nest_end(skb, nla);

        return 0;
}

/* Called with ovs_mutex or RCU read lock. */
int ovs_nla_put_identifier(const struct sw_flow *flow, struct sk_buff *skb)
{
        if (ovs_identifier_is_ufid(&flow->id))
                return nla_put(skb, OVS_FLOW_ATTR_UFID, flow->id.ufid_len,
                               flow->id.ufid);

        return ovs_nla_put_key(flow->id.unmasked_key, flow->id.unmasked_key,
                               OVS_FLOW_ATTR_KEY, false, skb);
}

/* Called with ovs_mutex or RCU read lock. */
int ovs_nla_put_masked_key(const struct sw_flow *flow, struct sk_buff *skb)
{
        return ovs_nla_put_key(&flow->key, &flow->key,
                                OVS_FLOW_ATTR_KEY, false, skb);
}

/* Called with ovs_mutex or RCU read lock. */
int ovs_nla_put_mask(const struct sw_flow *flow, struct sk_buff *skb)
{
        return ovs_nla_put_key(&flow->key, &flow->mask->key,
                                OVS_FLOW_ATTR_MASK, true, skb);
}

#define MAX_ACTIONS_BUFSIZE     (32 * 1024)

static struct sw_flow_actions *nla_alloc_flow_actions(int size, bool log)
{
        struct sw_flow_actions *sfa;

        if (size > MAX_ACTIONS_BUFSIZE) {
                OVS_NLERR(log, "Flow action size %u bytes exceeds max", size);
                return ERR_PTR(-EINVAL);
        }

        sfa = kmalloc(sizeof(*sfa) + size, GFP_KERNEL);
        if (!sfa)
                return ERR_PTR(-ENOMEM);

        sfa->actions_len = 0;
        return sfa;
}

static void ovs_nla_free_set_action(const struct nlattr *a)
{
        const struct nlattr *ovs_key = nla_data(a);
        struct ovs_tunnel_info *ovs_tun;

        switch (nla_type(ovs_key)) {
        case OVS_KEY_ATTR_TUNNEL_INFO:
                ovs_tun = nla_data(ovs_key);
                dst_release((struct dst_entry *)ovs_tun->tun_dst);
                break;
        }
}

void ovs_nla_free_flow_actions(struct sw_flow_actions *sf_acts)
{
        const struct nlattr *a;
        int rem;

        if (!sf_acts)
                return;

        nla_for_each_attr(a, sf_acts->actions, sf_acts->actions_len, rem) {
                switch (nla_type(a)) {
                case OVS_ACTION_ATTR_SET:
                        ovs_nla_free_set_action(a);
                        break;
                case OVS_ACTION_ATTR_CT:
                        ovs_ct_free_action(a);
                        break;
                }
        }

        kfree(sf_acts);
}

static void __ovs_nla_free_flow_actions(struct rcu_head *head)
{
        ovs_nla_free_flow_actions(container_of(head, struct sw_flow_actions, rcu));
}

/* 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_nla_free_flow_actions_rcu(struct sw_flow_actions *sf_acts)
{
        call_rcu(&sf_acts->rcu, __ovs_nla_free_flow_actions);
}

static struct nlattr *reserve_sfa_size(struct sw_flow_actions **sfa,
                                       int attr_len, bool log)
{

        struct sw_flow_actions *acts;
        int new_acts_size;
        int req_size = NLA_ALIGN(attr_len);
        int next_offset = offsetof(struct sw_flow_actions, actions) +
                                        (*sfa)->actions_len;

        if (req_size <= (ksize(*sfa) - next_offset))
                goto out;

        new_acts_size = ksize(*sfa) * 2;

        if (new_acts_size > MAX_ACTIONS_BUFSIZE) {
                if ((MAX_ACTIONS_BUFSIZE - next_offset) < req_size)
                        return ERR_PTR(-EMSGSIZE);
                new_acts_size = MAX_ACTIONS_BUFSIZE;
        }

        acts = nla_alloc_flow_actions(new_acts_size, log);
        if (IS_ERR(acts))
                return (void *)acts;

        memcpy(acts->actions, (*sfa)->actions, (*sfa)->actions_len);
        acts->actions_len = (*sfa)->actions_len;
        acts->orig_len = (*sfa)->orig_len;
        kfree(*sfa);
        *sfa = acts;

out:
        (*sfa)->actions_len += req_size;
        return  (struct nlattr *) ((unsigned char *)(*sfa) + next_offset);
}

static struct nlattr *__add_action(struct sw_flow_actions **sfa,
                                   int attrtype, void *data, int len, bool log)
{
        struct nlattr *a;

        a = reserve_sfa_size(sfa, nla_attr_size(len), log);
        if (IS_ERR(a))
                return a;

        a->nla_type = attrtype;
        a->nla_len = nla_attr_size(len);

        if (data)
                memcpy(nla_data(a), data, len);
        memset((unsigned char *) a + a->nla_len, 0, nla_padlen(len));

        return a;
}

int ovs_nla_add_action(struct sw_flow_actions **sfa, int attrtype, void *data,
                       int len, bool log)
{
        struct nlattr *a;

        a = __add_action(sfa, attrtype, data, len, log);

        return PTR_ERR_OR_ZERO(a);
}

static inline int add_nested_action_start(struct sw_flow_actions **sfa,
                                          int attrtype, bool log)
{
        int used = (*sfa)->actions_len;
        int err;

        err = ovs_nla_add_action(sfa, attrtype, NULL, 0, log);
        if (err)
                return err;

        return used;
}

static inline void add_nested_action_end(struct sw_flow_actions *sfa,
                                         int st_offset)
{
        struct nlattr *a = (struct nlattr *) ((unsigned char *)sfa->actions +
                                                               st_offset);

        a->nla_len = sfa->actions_len - st_offset;
}

static int __ovs_nla_copy_actions(struct net *net, const struct nlattr *attr,
                                  const struct sw_flow_key *key,
                                  int depth, struct sw_flow_actions **sfa,
                                  __be16 eth_type, __be16 vlan_tci, bool log);

static int validate_and_copy_sample(struct net *net, const struct nlattr *attr,
                                    const struct sw_flow_key *key, int depth,
                                    struct sw_flow_actions **sfa,
                                    __be16 eth_type, __be16 vlan_tci, bool log)
{
        const struct nlattr *attrs[OVS_SAMPLE_ATTR_MAX + 1];
        const struct nlattr *probability, *actions;
        const struct nlattr *a;
        int rem, start, err, st_acts;

        memset(attrs, 0, sizeof(attrs));
        nla_for_each_nested(a, attr, rem) {
                int type = nla_type(a);
                if (!type || type > OVS_SAMPLE_ATTR_MAX || attrs[type])
                        return -EINVAL;
                attrs[type] = a;
        }
        if (rem)
                return -EINVAL;

        probability = attrs[OVS_SAMPLE_ATTR_PROBABILITY];
        if (!probability || nla_len(probability) != sizeof(u32))
                return -EINVAL;

        actions = attrs[OVS_SAMPLE_ATTR_ACTIONS];
        if (!actions || (nla_len(actions) && nla_len(actions) < NLA_HDRLEN))
                return -EINVAL;

        /* validation done, copy sample action. */
        start = add_nested_action_start(sfa, OVS_ACTION_ATTR_SAMPLE, log);
        if (start < 0)
                return start;
        err = ovs_nla_add_action(sfa, OVS_SAMPLE_ATTR_PROBABILITY,
                                 nla_data(probability), sizeof(u32), log);
        if (err)
                return err;
        st_acts = add_nested_action_start(sfa, OVS_SAMPLE_ATTR_ACTIONS, log);
        if (st_acts < 0)
                return st_acts;

        err = __ovs_nla_copy_actions(net, actions, key, depth + 1, sfa,
                                     eth_type, vlan_tci, log);
        if (err)
                return err;

        add_nested_action_end(*sfa, st_acts);
        add_nested_action_end(*sfa, start);

        return 0;
}

void ovs_match_init(struct sw_flow_match *match,
                    struct sw_flow_key *key,
                    struct sw_flow_mask *mask)
{
        memset(match, 0, sizeof(*match));
        match->key = key;
        match->mask = mask;

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

        if (mask) {
                memset(&mask->key, 0, sizeof(mask->key));
                mask->range.start = mask->range.end = 0;
        }
}

static int validate_geneve_opts(struct sw_flow_key *key)
{
        struct geneve_opt *option;
        int opts_len = key->tun_opts_len;
        bool crit_opt = false;

        option = (struct geneve_opt *)TUN_METADATA_OPTS(key, key->tun_opts_len);
        while (opts_len > 0) {
                int len;

                if (opts_len < sizeof(*option))
                        return -EINVAL;

                len = sizeof(*option) + option->length * 4;
                if (len > opts_len)
                        return -EINVAL;

                crit_opt |= !!(option->type & GENEVE_CRIT_OPT_TYPE);

                option = (struct geneve_opt *)((u8 *)option + len);
                opts_len -= len;
        };

        key->tun_key.tun_flags |= crit_opt ? TUNNEL_CRIT_OPT : 0;

        return 0;
}

static int validate_and_copy_set_tun(const struct nlattr *attr,
                                     struct sw_flow_actions **sfa, bool log)
{
        struct sw_flow_match match;
        struct sw_flow_key key;
        struct metadata_dst *tun_dst;
        struct ip_tunnel_info *tun_info;
        struct ovs_tunnel_info *ovs_tun;
        struct nlattr *a;
        int err = 0, start, opts_type;

        ovs_match_init(&match, &key, NULL);
        opts_type = ip_tun_from_nlattr(nla_data(attr), &match, false, log);
        if (opts_type < 0)
                return opts_type;

        if (key.tun_opts_len) {
                switch (opts_type) {
                case OVS_TUNNEL_KEY_ATTR_GENEVE_OPTS:
                        err = validate_geneve_opts(&key);
                        if (err < 0)
                                return err;
                        break;
                case OVS_TUNNEL_KEY_ATTR_VXLAN_OPTS:
                        break;
                }
        };

        start = add_nested_action_start(sfa, OVS_ACTION_ATTR_SET, log);
        if (start < 0)
                return start;

        tun_dst = metadata_dst_alloc(key.tun_opts_len, GFP_KERNEL);
        if (!tun_dst)
                return -ENOMEM;

        err = dst_cache_init(&tun_dst->u.tun_info.dst_cache, GFP_KERNEL);
        if (err) {
                dst_release((struct dst_entry *)tun_dst);
                return err;
        }

        a = __add_action(sfa, OVS_KEY_ATTR_TUNNEL_INFO, NULL,
                         sizeof(*ovs_tun), log);
        if (IS_ERR(a)) {
                dst_release((struct dst_entry *)tun_dst);
                return PTR_ERR(a);
        }

        ovs_tun = nla_data(a);
        ovs_tun->tun_dst = tun_dst;

        tun_info = &tun_dst->u.tun_info;
        tun_info->mode = IP_TUNNEL_INFO_TX;
        if (key.tun_proto == AF_INET6)
                tun_info->mode |= IP_TUNNEL_INFO_IPV6;
        tun_info->key = key.tun_key;

        /* We need to store the options in the action itself since
         * everything else will go away after flow setup. We can append
         * it to tun_info and then point there.
         */
        ip_tunnel_info_opts_set(tun_info,
                                TUN_METADATA_OPTS(&key, key.tun_opts_len),
                                key.tun_opts_len);
        add_nested_action_end(*sfa, start);

        return err;
}

/* Return false if there are any non-masked bits set.
 * Mask follows data immediately, before any netlink padding.
 */
static bool validate_masked(u8 *data, int len)

{
        u8 *mask = data + len;

        while (len--)
                if (*data++ & ~*mask++)
                        return false;

        return true;
}

static int validate_set(const struct nlattr *a,
                        const struct sw_flow_key *flow_key,
                        struct sw_flow_actions **sfa,
                        bool *skip_copy, __be16 eth_type, bool masked, bool log)
{
        const struct nlattr *ovs_key = nla_data(a);
        int key_type = nla_type(ovs_key);
        size_t key_len;

        /* There can be only one key in a action */
        if (nla_total_size(nla_len(ovs_key)) != nla_len(a))
                return -EINVAL;

        key_len = nla_len(ovs_key);
        if (masked)
                key_len /= 2;

        if (key_type > OVS_KEY_ATTR_MAX ||
            !check_attr_len(key_len, ovs_key_lens[key_type].len))
                return -EINVAL;

        if (masked && !validate_masked(nla_data(ovs_key), key_len))
                return -EINVAL;

        switch (key_type) {
        const struct ovs_key_ipv4 *ipv4_key;
        const struct ovs_key_ipv6 *ipv6_key;
        int err;

        case OVS_KEY_ATTR_PRIORITY:
        case OVS_KEY_ATTR_SKB_MARK:
        case OVS_KEY_ATTR_CT_MARK:
        case OVS_KEY_ATTR_CT_LABELS:
        case OVS_KEY_ATTR_ETHERNET:
                break;

        case OVS_KEY_ATTR_TUNNEL:
                if (masked)
                        return -EINVAL; /* Masked tunnel set not supported. */

                *skip_copy = true;
                err = validate_and_copy_set_tun(a, sfa, log);
                if (err)
                        return err;
                break;

        case OVS_KEY_ATTR_IPV4:
                if (eth_type != htons(ETH_P_IP))
                        return -EINVAL;

                ipv4_key = nla_data(ovs_key);

                if (masked) {
                        const struct ovs_key_ipv4 *mask = ipv4_key + 1;

                        /* Non-writeable fields. */
                        if (mask->ipv4_proto || mask->ipv4_frag)
                                return -EINVAL;
                } else {
                        if (ipv4_key->ipv4_proto != flow_key->ip.proto)
                                return -EINVAL;

                        if (ipv4_key->ipv4_frag != flow_key->ip.frag)
                                return -EINVAL;
                }
                break;

        case OVS_KEY_ATTR_IPV6:
                if (eth_type != htons(ETH_P_IPV6))
                        return -EINVAL;

                ipv6_key = nla_data(ovs_key);

                if (masked) {
                        const struct ovs_key_ipv6 *mask = ipv6_key + 1;

                        /* Non-writeable fields. */
                        if (mask->ipv6_proto || mask->ipv6_frag)
                                return -EINVAL;

                        /* Invalid bits in the flow label mask? */
                        if (ntohl(mask->ipv6_label) & 0xFFF00000)
                                return -EINVAL;
                } else {
                        if (ipv6_key->ipv6_proto != flow_key->ip.proto)
                                return -EINVAL;

                        if (ipv6_key->ipv6_frag != flow_key->ip.frag)
                                return -EINVAL;
                }
                if (ntohl(ipv6_key->ipv6_label) & 0xFFF00000)
                        return -EINVAL;

                break;

        case OVS_KEY_ATTR_TCP:
                if ((eth_type != htons(ETH_P_IP) &&
                     eth_type != htons(ETH_P_IPV6)) ||
                    flow_key->ip.proto != IPPROTO_TCP)
                        return -EINVAL;

                break;

        case OVS_KEY_ATTR_UDP:
                if ((eth_type != htons(ETH_P_IP) &&
                     eth_type != htons(ETH_P_IPV6)) ||
                    flow_key->ip.proto != IPPROTO_UDP)
                        return -EINVAL;

                break;

        case OVS_KEY_ATTR_MPLS:
                if (!eth_p_mpls(eth_type))
                        return -EINVAL;
                break;

        case OVS_KEY_ATTR_SCTP:
                if ((eth_type != htons(ETH_P_IP) &&
                     eth_type != htons(ETH_P_IPV6)) ||
                    flow_key->ip.proto != IPPROTO_SCTP)
                        return -EINVAL;

                break;

        default:
                return -EINVAL;
        }

        /* Convert non-masked non-tunnel set actions to masked set actions. */
        if (!masked && key_type != OVS_KEY_ATTR_TUNNEL) {
                int start, len = key_len * 2;
                struct nlattr *at;

                *skip_copy = true;

                start = add_nested_action_start(sfa,
                                                OVS_ACTION_ATTR_SET_TO_MASKED,
                                                log);
                if (start < 0)
                        return start;

                at = __add_action(sfa, key_type, NULL, len, log);
                if (IS_ERR(at))
                        return PTR_ERR(at);

                memcpy(nla_data(at), nla_data(ovs_key), key_len); /* Key. */
                memset(nla_data(at) + key_len, 0xff, key_len);    /* Mask. */
                /* Clear non-writeable bits from otherwise writeable fields. */
                if (key_type == OVS_KEY_ATTR_IPV6) {
                        struct ovs_key_ipv6 *mask = nla_data(at) + key_len;

                        mask->ipv6_label &= htonl(0x000FFFFF);
                }
                add_nested_action_end(*sfa, start);
        }

        return 0;
}

static int validate_userspace(const struct nlattr *attr)
{
        static const struct nla_policy userspace_policy[OVS_USERSPACE_ATTR_MAX + 1] = {
                [OVS_USERSPACE_ATTR_PID] = {.type = NLA_U32 },
                [OVS_USERSPACE_ATTR_USERDATA] = {.type = NLA_UNSPEC },
                [OVS_USERSPACE_ATTR_EGRESS_TUN_PORT] = {.type = NLA_U32 },
        };
        struct nlattr *a[OVS_USERSPACE_ATTR_MAX + 1];
        int error;

        error = nla_parse_nested(a, OVS_USERSPACE_ATTR_MAX,
                                 attr, userspace_policy);
        if (error)
                return error;

        if (!a[OVS_USERSPACE_ATTR_PID] ||
            !nla_get_u32(a[OVS_USERSPACE_ATTR_PID]))
                return -EINVAL;

        return 0;
}

static int copy_action(const struct nlattr *from,
                       struct sw_flow_actions **sfa, bool log)
{
        int totlen = NLA_ALIGN(from->nla_len);
        struct nlattr *to;

        to = reserve_sfa_size(sfa, from->nla_len, log);
        if (IS_ERR(to))
                return PTR_ERR(to);

        memcpy(to, from, totlen);
        return 0;
}

static int __ovs_nla_copy_actions(struct net *net, const struct nlattr *attr,
                                  const struct sw_flow_key *key,
                                  int depth, struct sw_flow_actions **sfa,
                                  __be16 eth_type, __be16 vlan_tci, bool log)
{
        const struct nlattr *a;
        int rem, err;

        if (depth >= SAMPLE_ACTION_DEPTH)
                return -EOVERFLOW;

        nla_for_each_nested(a, attr, rem) {
                /* Expected argument lengths, (u32)-1 for variable length. */
                static const u32 action_lens[OVS_ACTION_ATTR_MAX + 1] = {
                        [OVS_ACTION_ATTR_OUTPUT] = sizeof(u32),
                        [OVS_ACTION_ATTR_RECIRC] = sizeof(u32),
                        [OVS_ACTION_ATTR_USERSPACE] = (u32)-1,
                        [OVS_ACTION_ATTR_PUSH_MPLS] = sizeof(struct ovs_action_push_mpls),
                        [OVS_ACTION_ATTR_POP_MPLS] = sizeof(__be16),
                        [OVS_ACTION_ATTR_PUSH_VLAN] = sizeof(struct ovs_action_push_vlan),
                        [OVS_ACTION_ATTR_POP_VLAN] = 0,
                        [OVS_ACTION_ATTR_SET] = (u32)-1,
                        [OVS_ACTION_ATTR_SET_MASKED] = (u32)-1,
                        [OVS_ACTION_ATTR_SAMPLE] = (u32)-1,
                        [OVS_ACTION_ATTR_HASH] = sizeof(struct ovs_action_hash),
                        [OVS_ACTION_ATTR_CT] = (u32)-1,
                        [OVS_ACTION_ATTR_TRUNC] = sizeof(struct ovs_action_trunc),
                };
                const struct ovs_action_push_vlan *vlan;
                int type = nla_type(a);
                bool skip_copy;

                if (type > OVS_ACTION_ATTR_MAX ||
                    (action_lens[type] != nla_len(a) &&
                     action_lens[type] != (u32)-1))
                        return -EINVAL;

                skip_copy = false;
                switch (type) {
                case OVS_ACTION_ATTR_UNSPEC:
                        return -EINVAL;

                case OVS_ACTION_ATTR_USERSPACE:
                        err = validate_userspace(a);
                        if (err)
                                return err;
                        break;

                case OVS_ACTION_ATTR_OUTPUT:
                        if (nla_get_u32(a) >= DP_MAX_PORTS)
                                return -EINVAL;
                        break;

                case OVS_ACTION_ATTR_TRUNC: {
                        const struct ovs_action_trunc *trunc = nla_data(a);

                        if (trunc->max_len < ETH_HLEN)
                                return -EINVAL;
                        break;
                }

                case OVS_ACTION_ATTR_HASH: {
                        const struct ovs_action_hash *act_hash = nla_data(a);

                        switch (act_hash->hash_alg) {
                        case OVS_HASH_ALG_L4:
                                break;
                        default:
                                return  -EINVAL;
                        }

                        break;
                }

                case OVS_ACTION_ATTR_POP_VLAN:
                        vlan_tci = htons(0);
                        break;

                case OVS_ACTION_ATTR_PUSH_VLAN:
                        vlan = nla_data(a);
                        if (vlan->vlan_tpid != htons(ETH_P_8021Q))
                                return -EINVAL;
                        if (!(vlan->vlan_tci & htons(VLAN_TAG_PRESENT)))
                                return -EINVAL;
                        vlan_tci = vlan->vlan_tci;
                        break;

                case OVS_ACTION_ATTR_RECIRC:
                        break;

                case OVS_ACTION_ATTR_PUSH_MPLS: {
                        const struct ovs_action_push_mpls *mpls = nla_data(a);

                        if (!eth_p_mpls(mpls->mpls_ethertype))
                                return -EINVAL;
                        /* Prohibit push MPLS other than to a white list
                         * for packets that have a known tag order.
                         */
                        if (vlan_tci & htons(VLAN_TAG_PRESENT) ||
                            (eth_type != htons(ETH_P_IP) &&
                             eth_type != htons(ETH_P_IPV6) &&
                             eth_type != htons(ETH_P_ARP) &&
                             eth_type != htons(ETH_P_RARP) &&
                             !eth_p_mpls(eth_type)))
                                return -EINVAL;
                        eth_type = mpls->mpls_ethertype;
                        break;
                }

                case OVS_ACTION_ATTR_POP_MPLS:
                        if (vlan_tci & htons(VLAN_TAG_PRESENT) ||
                            !eth_p_mpls(eth_type))
                                return -EINVAL;

                        /* Disallow subsequent L2.5+ set and mpls_pop actions
                         * as there is no check here to ensure that the new
                         * eth_type is valid and thus set actions could
                         * write off the end of the packet or otherwise
                         * corrupt it.
                         *
                         * Support for these actions is planned using packet
                         * recirculation.
                         */
                        eth_type = htons(0);
                        break;

                case OVS_ACTION_ATTR_SET:
                        err = validate_set(a, key, sfa,
                                           &skip_copy, eth_type, false, log);
                        if (err)
                                return err;
                        break;

                case OVS_ACTION_ATTR_SET_MASKED:
                        err = validate_set(a, key, sfa,
                                           &skip_copy, eth_type, true, log);
                        if (err)
                                return err;
                        break;

                case OVS_ACTION_ATTR_SAMPLE:
                        err = validate_and_copy_sample(net, a, key, depth, sfa,
                                                       eth_type, vlan_tci, log);
                        if (err)
                                return err;
                        skip_copy = true;
                        break;

                case OVS_ACTION_ATTR_CT:
                        err = ovs_ct_copy_action(net, a, key, sfa, log);
                        if (err)
                                return err;
                        skip_copy = true;
                        break;

                default:
                        OVS_NLERR(log, "Unknown Action type %d", type);
                        return -EINVAL;
                }
                if (!skip_copy) {
                        err = copy_action(a, sfa, log);
                        if (err)
                                return err;
                }
        }

        if (rem > 0)
                return -EINVAL;

        return 0;
}

/* 'key' must be the masked key. */
int ovs_nla_copy_actions(struct net *net, const struct nlattr *attr,
                         const struct sw_flow_key *key,
                         struct sw_flow_actions **sfa, bool log)
{
        int err;

        *sfa = nla_alloc_flow_actions(nla_len(attr), log);
        if (IS_ERR(*sfa))
                return PTR_ERR(*sfa);

        (*sfa)->orig_len = nla_len(attr);
        err = __ovs_nla_copy_actions(net, attr, key, 0, sfa, key->eth.type,
                                     key->eth.tci, log);
        if (err)
                ovs_nla_free_flow_actions(*sfa);

        return err;
}

static int sample_action_to_attr(const struct nlattr *attr, struct sk_buff *skb)
{
        const struct nlattr *a;
        struct nlattr *start;
        int err = 0, rem;

        start = nla_nest_start(skb, OVS_ACTION_ATTR_SAMPLE);
        if (!start)
                return -EMSGSIZE;

        nla_for_each_nested(a, attr, rem) {
                int type = nla_type(a);
                struct nlattr *st_sample;

                switch (type) {
                case OVS_SAMPLE_ATTR_PROBABILITY:
                        if (nla_put(skb, OVS_SAMPLE_ATTR_PROBABILITY,
                                    sizeof(u32), nla_data(a)))
                                return -EMSGSIZE;
                        break;
                case OVS_SAMPLE_ATTR_ACTIONS:
                        st_sample = nla_nest_start(skb, OVS_SAMPLE_ATTR_ACTIONS);
                        if (!st_sample)
                                return -EMSGSIZE;
                        err = ovs_nla_put_actions(nla_data(a), nla_len(a), skb);
                        if (err)
                                return err;
                        nla_nest_end(skb, st_sample);
                        break;
                }
        }

        nla_nest_end(skb, start);
        return err;
}

static int set_action_to_attr(const struct nlattr *a, struct sk_buff *skb)
{
        const struct nlattr *ovs_key = nla_data(a);
        int key_type = nla_type(ovs_key);
        struct nlattr *start;
        int err;

        switch (key_type) {
        case OVS_KEY_ATTR_TUNNEL_INFO: {
                struct ovs_tunnel_info *ovs_tun = nla_data(ovs_key);
                struct ip_tunnel_info *tun_info = &ovs_tun->tun_dst->u.tun_info;

                start = nla_nest_start(skb, OVS_ACTION_ATTR_SET);
                if (!start)
                        return -EMSGSIZE;

                err =  ip_tun_to_nlattr(skb, &tun_info->key,
                                        ip_tunnel_info_opts(tun_info),
                                        tun_info->options_len,
                                        ip_tunnel_info_af(tun_info));
                if (err)
                        return err;
                nla_nest_end(skb, start);
                break;
        }
        default:
                if (nla_put(skb, OVS_ACTION_ATTR_SET, nla_len(a), ovs_key))
                        return -EMSGSIZE;
                break;
        }

        return 0;
}

static int masked_set_action_to_set_action_attr(const struct nlattr *a,
                                                struct sk_buff *skb)
{
        const struct nlattr *ovs_key = nla_data(a);
        struct nlattr *nla;
        size_t key_len = nla_len(ovs_key) / 2;

        /* Revert the conversion we did from a non-masked set action to
         * masked set action.
         */
        nla = nla_nest_start(skb, OVS_ACTION_ATTR_SET);
        if (!nla)
                return -EMSGSIZE;

        if (nla_put(skb, nla_type(ovs_key), key_len, nla_data(ovs_key)))
                return -EMSGSIZE;

        nla_nest_end(skb, nla);
        return 0;
}

int ovs_nla_put_actions(const struct nlattr *attr, int len, struct sk_buff *skb)
{
        const struct nlattr *a;
        int rem, err;

        nla_for_each_attr(a, attr, len, rem) {
                int type = nla_type(a);

                switch (type) {
                case OVS_ACTION_ATTR_SET:
                        err = set_action_to_attr(a, skb);
                        if (err)
                                return err;
                        break;

                case OVS_ACTION_ATTR_SET_TO_MASKED:
                        err = masked_set_action_to_set_action_attr(a, skb);
                        if (err)
                                return err;
                        break;

                case OVS_ACTION_ATTR_SAMPLE:
                        err = sample_action_to_attr(a, skb);
                        if (err)
                                return err;
                        break;

                case OVS_ACTION_ATTR_CT:
                        err = ovs_ct_action_to_attr(nla_data(a), skb);
                        if (err)
                                return err;
                        break;

                default:
                        if (nla_put(skb, type, nla_len(a), nla_data(a)))
                                return -EMSGSIZE;
                        break;
                }
        }

        return 0;
}