Merge tag 'for-5.15-tag' of git://git.kernel.org/pub/scm/linux/kernel/git/kdave/linux

[mirror_ubuntu-jammy-kernel.git] / net / netfilter / nf_flow_table_offload.c

#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/module.h>
#include <linux/netfilter.h>
#include <linux/rhashtable.h>
#include <linux/netdevice.h>
#include <linux/tc_act/tc_csum.h>
#include <net/flow_offload.h>
#include <net/netfilter/nf_flow_table.h>
#include <net/netfilter/nf_tables.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_acct.h>
#include <net/netfilter/nf_conntrack_core.h>
#include <net/netfilter/nf_conntrack_tuple.h>

static struct workqueue_struct *nf_flow_offload_add_wq;
static struct workqueue_struct *nf_flow_offload_del_wq;
static struct workqueue_struct *nf_flow_offload_stats_wq;

struct flow_offload_work {
        struct list_head        list;
        enum flow_cls_command   cmd;
        int                     priority;
        struct nf_flowtable     *flowtable;
        struct flow_offload     *flow;
        struct work_struct      work;
};

#define NF_FLOW_DISSECTOR(__match, __type, __field)     \
        (__match)->dissector.offset[__type] =           \
                offsetof(struct nf_flow_key, __field)

static void nf_flow_rule_lwt_match(struct nf_flow_match *match,
                                   struct ip_tunnel_info *tun_info)
{
        struct nf_flow_key *mask = &match->mask;
        struct nf_flow_key *key = &match->key;
        unsigned int enc_keys;

        if (!tun_info || !(tun_info->mode & IP_TUNNEL_INFO_TX))
                return;

        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_ENC_CONTROL, enc_control);
        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_ENC_KEYID, enc_key_id);
        key->enc_key_id.keyid = tunnel_id_to_key32(tun_info->key.tun_id);
        mask->enc_key_id.keyid = 0xffffffff;
        enc_keys = BIT(FLOW_DISSECTOR_KEY_ENC_KEYID) |
                   BIT(FLOW_DISSECTOR_KEY_ENC_CONTROL);

        if (ip_tunnel_info_af(tun_info) == AF_INET) {
                NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS,
                                  enc_ipv4);
                key->enc_ipv4.src = tun_info->key.u.ipv4.dst;
                key->enc_ipv4.dst = tun_info->key.u.ipv4.src;
                if (key->enc_ipv4.src)
                        mask->enc_ipv4.src = 0xffffffff;
                if (key->enc_ipv4.dst)
                        mask->enc_ipv4.dst = 0xffffffff;
                enc_keys |= BIT(FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS);
                key->enc_control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
        } else {
                memcpy(&key->enc_ipv6.src, &tun_info->key.u.ipv6.dst,
                       sizeof(struct in6_addr));
                memcpy(&key->enc_ipv6.dst, &tun_info->key.u.ipv6.src,
                       sizeof(struct in6_addr));
                if (memcmp(&key->enc_ipv6.src, &in6addr_any,
                           sizeof(struct in6_addr)))
                        memset(&key->enc_ipv6.src, 0xff,
                               sizeof(struct in6_addr));
                if (memcmp(&key->enc_ipv6.dst, &in6addr_any,
                           sizeof(struct in6_addr)))
                        memset(&key->enc_ipv6.dst, 0xff,
                               sizeof(struct in6_addr));
                enc_keys |= BIT(FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS);
                key->enc_control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
        }

        match->dissector.used_keys |= enc_keys;
}

static void nf_flow_rule_vlan_match(struct flow_dissector_key_vlan *key,
                                    struct flow_dissector_key_vlan *mask,
                                    u16 vlan_id, __be16 proto)
{
        key->vlan_id = vlan_id;
        mask->vlan_id = VLAN_VID_MASK;
        key->vlan_tpid = proto;
        mask->vlan_tpid = 0xffff;
}

static int nf_flow_rule_match(struct nf_flow_match *match,
                              const struct flow_offload_tuple *tuple,
                              struct dst_entry *other_dst)
{
        struct nf_flow_key *mask = &match->mask;
        struct nf_flow_key *key = &match->key;
        struct ip_tunnel_info *tun_info;
        bool vlan_encap = false;

        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_META, meta);
        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_CONTROL, control);
        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_BASIC, basic);
        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_IPV4_ADDRS, ipv4);
        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_IPV6_ADDRS, ipv6);
        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_TCP, tcp);
        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_PORTS, tp);

        if (other_dst && other_dst->lwtstate) {
                tun_info = lwt_tun_info(other_dst->lwtstate);
                nf_flow_rule_lwt_match(match, tun_info);
        }

        key->meta.ingress_ifindex = tuple->iifidx;
        mask->meta.ingress_ifindex = 0xffffffff;

        if (tuple->encap_num > 0 && !(tuple->in_vlan_ingress & BIT(0)) &&
            tuple->encap[0].proto == htons(ETH_P_8021Q)) {
                NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_VLAN, vlan);
                nf_flow_rule_vlan_match(&key->vlan, &mask->vlan,
                                        tuple->encap[0].id,
                                        tuple->encap[0].proto);
                vlan_encap = true;
        }

        if (tuple->encap_num > 1 && !(tuple->in_vlan_ingress & BIT(1)) &&
            tuple->encap[1].proto == htons(ETH_P_8021Q)) {
                if (vlan_encap) {
                        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_CVLAN,
                                          cvlan);
                        nf_flow_rule_vlan_match(&key->cvlan, &mask->cvlan,
                                                tuple->encap[1].id,
                                                tuple->encap[1].proto);
                } else {
                        NF_FLOW_DISSECTOR(match, FLOW_DISSECTOR_KEY_VLAN,
                                          vlan);
                        nf_flow_rule_vlan_match(&key->vlan, &mask->vlan,
                                                tuple->encap[1].id,
                                                tuple->encap[1].proto);
                }
        }

        switch (tuple->l3proto) {
        case AF_INET:
                key->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
                key->basic.n_proto = htons(ETH_P_IP);
                key->ipv4.src = tuple->src_v4.s_addr;
                mask->ipv4.src = 0xffffffff;
                key->ipv4.dst = tuple->dst_v4.s_addr;
                mask->ipv4.dst = 0xffffffff;
                break;
       case AF_INET6:
                key->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
                key->basic.n_proto = htons(ETH_P_IPV6);
                key->ipv6.src = tuple->src_v6;
                memset(&mask->ipv6.src, 0xff, sizeof(mask->ipv6.src));
                key->ipv6.dst = tuple->dst_v6;
                memset(&mask->ipv6.dst, 0xff, sizeof(mask->ipv6.dst));
                break;
        default:
                return -EOPNOTSUPP;
        }
        mask->control.addr_type = 0xffff;
        match->dissector.used_keys |= BIT(key->control.addr_type);
        mask->basic.n_proto = 0xffff;

        switch (tuple->l4proto) {
        case IPPROTO_TCP:
                key->tcp.flags = 0;
                mask->tcp.flags = cpu_to_be16(be32_to_cpu(TCP_FLAG_RST | TCP_FLAG_FIN) >> 16);
                match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_TCP);
                break;
        case IPPROTO_UDP:
                break;
        default:
                return -EOPNOTSUPP;
        }

        key->basic.ip_proto = tuple->l4proto;
        mask->basic.ip_proto = 0xff;

        key->tp.src = tuple->src_port;
        mask->tp.src = 0xffff;
        key->tp.dst = tuple->dst_port;
        mask->tp.dst = 0xffff;

        match->dissector.used_keys |= BIT(FLOW_DISSECTOR_KEY_META) |
                                      BIT(FLOW_DISSECTOR_KEY_CONTROL) |
                                      BIT(FLOW_DISSECTOR_KEY_BASIC) |
                                      BIT(FLOW_DISSECTOR_KEY_PORTS);
        return 0;
}

static void flow_offload_mangle(struct flow_action_entry *entry,
                                enum flow_action_mangle_base htype, u32 offset,
                                const __be32 *value, const __be32 *mask)
{
        entry->id = FLOW_ACTION_MANGLE;
        entry->mangle.htype = htype;
        entry->mangle.offset = offset;
        memcpy(&entry->mangle.mask, mask, sizeof(u32));
        memcpy(&entry->mangle.val, value, sizeof(u32));
}

static inline struct flow_action_entry *
flow_action_entry_next(struct nf_flow_rule *flow_rule)
{
        int i = flow_rule->rule->action.num_entries++;

        return &flow_rule->rule->action.entries[i];
}

static int flow_offload_eth_src(struct net *net,
                                const struct flow_offload *flow,
                                enum flow_offload_tuple_dir dir,
                                struct nf_flow_rule *flow_rule)
{
        struct flow_action_entry *entry0 = flow_action_entry_next(flow_rule);
        struct flow_action_entry *entry1 = flow_action_entry_next(flow_rule);
        const struct flow_offload_tuple *other_tuple, *this_tuple;
        struct net_device *dev = NULL;
        const unsigned char *addr;
        u32 mask, val;
        u16 val16;

        this_tuple = &flow->tuplehash[dir].tuple;

        switch (this_tuple->xmit_type) {
        case FLOW_OFFLOAD_XMIT_DIRECT:
                addr = this_tuple->out.h_source;
                break;
        case FLOW_OFFLOAD_XMIT_NEIGH:
                other_tuple = &flow->tuplehash[!dir].tuple;
                dev = dev_get_by_index(net, other_tuple->iifidx);
                if (!dev)
                        return -ENOENT;

                addr = dev->dev_addr;
                break;
        default:
                return -EOPNOTSUPP;
        }

        mask = ~0xffff0000;
        memcpy(&val16, addr, 2);
        val = val16 << 16;
        flow_offload_mangle(entry0, FLOW_ACT_MANGLE_HDR_TYPE_ETH, 4,
                            &val, &mask);

        mask = ~0xffffffff;
        memcpy(&val, addr + 2, 4);
        flow_offload_mangle(entry1, FLOW_ACT_MANGLE_HDR_TYPE_ETH, 8,
                            &val, &mask);

        dev_put(dev);

        return 0;
}

static int flow_offload_eth_dst(struct net *net,
                                const struct flow_offload *flow,
                                enum flow_offload_tuple_dir dir,
                                struct nf_flow_rule *flow_rule)
{
        struct flow_action_entry *entry0 = flow_action_entry_next(flow_rule);
        struct flow_action_entry *entry1 = flow_action_entry_next(flow_rule);
        const struct flow_offload_tuple *other_tuple, *this_tuple;
        const struct dst_entry *dst_cache;
        unsigned char ha[ETH_ALEN];
        struct neighbour *n;
        const void *daddr;
        u32 mask, val;
        u8 nud_state;
        u16 val16;

        this_tuple = &flow->tuplehash[dir].tuple;

        switch (this_tuple->xmit_type) {
        case FLOW_OFFLOAD_XMIT_DIRECT:
                ether_addr_copy(ha, this_tuple->out.h_dest);
                break;
        case FLOW_OFFLOAD_XMIT_NEIGH:
                other_tuple = &flow->tuplehash[!dir].tuple;
                daddr = &other_tuple->src_v4;
                dst_cache = this_tuple->dst_cache;
                n = dst_neigh_lookup(dst_cache, daddr);
                if (!n)
                        return -ENOENT;

                read_lock_bh(&n->lock);
                nud_state = n->nud_state;
                ether_addr_copy(ha, n->ha);
                read_unlock_bh(&n->lock);
                neigh_release(n);

                if (!(nud_state & NUD_VALID))
                        return -ENOENT;
                break;
        default:
                return -EOPNOTSUPP;
        }

        mask = ~0xffffffff;
        memcpy(&val, ha, 4);
        flow_offload_mangle(entry0, FLOW_ACT_MANGLE_HDR_TYPE_ETH, 0,
                            &val, &mask);

        mask = ~0x0000ffff;
        memcpy(&val16, ha + 4, 2);
        val = val16;
        flow_offload_mangle(entry1, FLOW_ACT_MANGLE_HDR_TYPE_ETH, 4,
                            &val, &mask);

        return 0;
}

static void flow_offload_ipv4_snat(struct net *net,
                                   const struct flow_offload *flow,
                                   enum flow_offload_tuple_dir dir,
                                   struct nf_flow_rule *flow_rule)
{
        struct flow_action_entry *entry = flow_action_entry_next(flow_rule);
        u32 mask = ~htonl(0xffffffff);
        __be32 addr;
        u32 offset;

        switch (dir) {
        case FLOW_OFFLOAD_DIR_ORIGINAL:
                addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_v4.s_addr;
                offset = offsetof(struct iphdr, saddr);
                break;
        case FLOW_OFFLOAD_DIR_REPLY:
                addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_v4.s_addr;
                offset = offsetof(struct iphdr, daddr);
                break;
        default:
                return;
        }

        flow_offload_mangle(entry, FLOW_ACT_MANGLE_HDR_TYPE_IP4, offset,
                            &addr, &mask);
}

static void flow_offload_ipv4_dnat(struct net *net,
                                   const struct flow_offload *flow,
                                   enum flow_offload_tuple_dir dir,
                                   struct nf_flow_rule *flow_rule)
{
        struct flow_action_entry *entry = flow_action_entry_next(flow_rule);
        u32 mask = ~htonl(0xffffffff);
        __be32 addr;
        u32 offset;

        switch (dir) {
        case FLOW_OFFLOAD_DIR_ORIGINAL:
                addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v4.s_addr;
                offset = offsetof(struct iphdr, daddr);
                break;
        case FLOW_OFFLOAD_DIR_REPLY:
                addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v4.s_addr;
                offset = offsetof(struct iphdr, saddr);
                break;
        default:
                return;
        }

        flow_offload_mangle(entry, FLOW_ACT_MANGLE_HDR_TYPE_IP4, offset,
                            &addr, &mask);
}

static void flow_offload_ipv6_mangle(struct nf_flow_rule *flow_rule,
                                     unsigned int offset,
                                     const __be32 *addr, const __be32 *mask)
{
        struct flow_action_entry *entry;
        int i, j;

        for (i = 0, j = 0; i < sizeof(struct in6_addr) / sizeof(u32); i += sizeof(u32), j++) {
                entry = flow_action_entry_next(flow_rule);
                flow_offload_mangle(entry, FLOW_ACT_MANGLE_HDR_TYPE_IP6,
                                    offset + i, &addr[j], mask);
        }
}

static void flow_offload_ipv6_snat(struct net *net,
                                   const struct flow_offload *flow,
                                   enum flow_offload_tuple_dir dir,
                                   struct nf_flow_rule *flow_rule)
{
        u32 mask = ~htonl(0xffffffff);
        const __be32 *addr;
        u32 offset;

        switch (dir) {
        case FLOW_OFFLOAD_DIR_ORIGINAL:
                addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_v6.s6_addr32;
                offset = offsetof(struct ipv6hdr, saddr);
                break;
        case FLOW_OFFLOAD_DIR_REPLY:
                addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_v6.s6_addr32;
                offset = offsetof(struct ipv6hdr, daddr);
                break;
        default:
                return;
        }

        flow_offload_ipv6_mangle(flow_rule, offset, addr, &mask);
}

static void flow_offload_ipv6_dnat(struct net *net,
                                   const struct flow_offload *flow,
                                   enum flow_offload_tuple_dir dir,
                                   struct nf_flow_rule *flow_rule)
{
        u32 mask = ~htonl(0xffffffff);
        const __be32 *addr;
        u32 offset;

        switch (dir) {
        case FLOW_OFFLOAD_DIR_ORIGINAL:
                addr = flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_v6.s6_addr32;
                offset = offsetof(struct ipv6hdr, daddr);
                break;
        case FLOW_OFFLOAD_DIR_REPLY:
                addr = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_v6.s6_addr32;
                offset = offsetof(struct ipv6hdr, saddr);
                break;
        default:
                return;
        }

        flow_offload_ipv6_mangle(flow_rule, offset, addr, &mask);
}

static int flow_offload_l4proto(const struct flow_offload *flow)
{
        u8 protonum = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.l4proto;
        u8 type = 0;

        switch (protonum) {
        case IPPROTO_TCP:
                type = FLOW_ACT_MANGLE_HDR_TYPE_TCP;
                break;
        case IPPROTO_UDP:
                type = FLOW_ACT_MANGLE_HDR_TYPE_UDP;
                break;
        default:
                break;
        }

        return type;
}

static void flow_offload_port_snat(struct net *net,
                                   const struct flow_offload *flow,
                                   enum flow_offload_tuple_dir dir,
                                   struct nf_flow_rule *flow_rule)
{
        struct flow_action_entry *entry = flow_action_entry_next(flow_rule);
        u32 mask, port;
        u32 offset;

        switch (dir) {
        case FLOW_OFFLOAD_DIR_ORIGINAL:
                port = ntohs(flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.dst_port);
                offset = 0; /* offsetof(struct tcphdr, source); */
                port = htonl(port << 16);
                mask = ~htonl(0xffff0000);
                break;
        case FLOW_OFFLOAD_DIR_REPLY:
                port = ntohs(flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.src_port);
                offset = 0; /* offsetof(struct tcphdr, dest); */
                port = htonl(port);
                mask = ~htonl(0xffff);
                break;
        default:
                return;
        }

        flow_offload_mangle(entry, flow_offload_l4proto(flow), offset,
                            &port, &mask);
}

static void flow_offload_port_dnat(struct net *net,
                                   const struct flow_offload *flow,
                                   enum flow_offload_tuple_dir dir,
                                   struct nf_flow_rule *flow_rule)
{
        struct flow_action_entry *entry = flow_action_entry_next(flow_rule);
        u32 mask, port;
        u32 offset;

        switch (dir) {
        case FLOW_OFFLOAD_DIR_ORIGINAL:
                port = ntohs(flow->tuplehash[FLOW_OFFLOAD_DIR_REPLY].tuple.src_port);
                offset = 0; /* offsetof(struct tcphdr, dest); */
                port = htonl(port);
                mask = ~htonl(0xffff);
                break;
        case FLOW_OFFLOAD_DIR_REPLY:
                port = ntohs(flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.dst_port);
                offset = 0; /* offsetof(struct tcphdr, source); */
                port = htonl(port << 16);
                mask = ~htonl(0xffff0000);
                break;
        default:
                return;
        }

        flow_offload_mangle(entry, flow_offload_l4proto(flow), offset,
                            &port, &mask);
}

static void flow_offload_ipv4_checksum(struct net *net,
                                       const struct flow_offload *flow,
                                       struct nf_flow_rule *flow_rule)
{
        u8 protonum = flow->tuplehash[FLOW_OFFLOAD_DIR_ORIGINAL].tuple.l4proto;
        struct flow_action_entry *entry = flow_action_entry_next(flow_rule);

        entry->id = FLOW_ACTION_CSUM;
        entry->csum_flags = TCA_CSUM_UPDATE_FLAG_IPV4HDR;

        switch (protonum) {
        case IPPROTO_TCP:
                entry->csum_flags |= TCA_CSUM_UPDATE_FLAG_TCP;
                break;
        case IPPROTO_UDP:
                entry->csum_flags |= TCA_CSUM_UPDATE_FLAG_UDP;
                break;
        }
}

static void flow_offload_redirect(struct net *net,
                                  const struct flow_offload *flow,
                                  enum flow_offload_tuple_dir dir,
                                  struct nf_flow_rule *flow_rule)
{
        const struct flow_offload_tuple *this_tuple, *other_tuple;
        struct flow_action_entry *entry;
        struct net_device *dev;
        int ifindex;

        this_tuple = &flow->tuplehash[dir].tuple;
        switch (this_tuple->xmit_type) {
        case FLOW_OFFLOAD_XMIT_DIRECT:
                this_tuple = &flow->tuplehash[dir].tuple;
                ifindex = this_tuple->out.hw_ifidx;
                break;
        case FLOW_OFFLOAD_XMIT_NEIGH:
                other_tuple = &flow->tuplehash[!dir].tuple;
                ifindex = other_tuple->iifidx;
                break;
        default:
                return;
        }

        dev = dev_get_by_index(net, ifindex);
        if (!dev)
                return;

        entry = flow_action_entry_next(flow_rule);
        entry->id = FLOW_ACTION_REDIRECT;
        entry->dev = dev;
}

static void flow_offload_encap_tunnel(const struct flow_offload *flow,
                                      enum flow_offload_tuple_dir dir,
                                      struct nf_flow_rule *flow_rule)
{
        const struct flow_offload_tuple *this_tuple;
        struct flow_action_entry *entry;
        struct dst_entry *dst;

        this_tuple = &flow->tuplehash[dir].tuple;
        if (this_tuple->xmit_type == FLOW_OFFLOAD_XMIT_DIRECT)
                return;

        dst = this_tuple->dst_cache;
        if (dst && dst->lwtstate) {
                struct ip_tunnel_info *tun_info;

                tun_info = lwt_tun_info(dst->lwtstate);
                if (tun_info && (tun_info->mode & IP_TUNNEL_INFO_TX)) {
                        entry = flow_action_entry_next(flow_rule);
                        entry->id = FLOW_ACTION_TUNNEL_ENCAP;
                        entry->tunnel = tun_info;
                }
        }
}

static void flow_offload_decap_tunnel(const struct flow_offload *flow,
                                      enum flow_offload_tuple_dir dir,
                                      struct nf_flow_rule *flow_rule)
{
        const struct flow_offload_tuple *other_tuple;
        struct flow_action_entry *entry;
        struct dst_entry *dst;

        other_tuple = &flow->tuplehash[!dir].tuple;
        if (other_tuple->xmit_type == FLOW_OFFLOAD_XMIT_DIRECT)
                return;

        dst = other_tuple->dst_cache;
        if (dst && dst->lwtstate) {
                struct ip_tunnel_info *tun_info;

                tun_info = lwt_tun_info(dst->lwtstate);
                if (tun_info && (tun_info->mode & IP_TUNNEL_INFO_TX)) {
                        entry = flow_action_entry_next(flow_rule);
                        entry->id = FLOW_ACTION_TUNNEL_DECAP;
                }
        }
}

static int
nf_flow_rule_route_common(struct net *net, const struct flow_offload *flow,
                          enum flow_offload_tuple_dir dir,
                          struct nf_flow_rule *flow_rule)
{
        const struct flow_offload_tuple *other_tuple;
        const struct flow_offload_tuple *tuple;
        int i;

        flow_offload_decap_tunnel(flow, dir, flow_rule);
        flow_offload_encap_tunnel(flow, dir, flow_rule);

        if (flow_offload_eth_src(net, flow, dir, flow_rule) < 0 ||
            flow_offload_eth_dst(net, flow, dir, flow_rule) < 0)
                return -1;

        tuple = &flow->tuplehash[dir].tuple;

        for (i = 0; i < tuple->encap_num; i++) {
                struct flow_action_entry *entry;

                if (tuple->in_vlan_ingress & BIT(i))
                        continue;

                if (tuple->encap[i].proto == htons(ETH_P_8021Q)) {
                        entry = flow_action_entry_next(flow_rule);
                        entry->id = FLOW_ACTION_VLAN_POP;
                }
        }

        other_tuple = &flow->tuplehash[!dir].tuple;

        for (i = 0; i < other_tuple->encap_num; i++) {
                struct flow_action_entry *entry;

                if (other_tuple->in_vlan_ingress & BIT(i))
                        continue;

                entry = flow_action_entry_next(flow_rule);

                switch (other_tuple->encap[i].proto) {
                case htons(ETH_P_PPP_SES):
                        entry->id = FLOW_ACTION_PPPOE_PUSH;
                        entry->pppoe.sid = other_tuple->encap[i].id;
                        break;
                case htons(ETH_P_8021Q):
                        entry->id = FLOW_ACTION_VLAN_PUSH;
                        entry->vlan.vid = other_tuple->encap[i].id;
                        entry->vlan.proto = other_tuple->encap[i].proto;
                        break;
                }
        }

        return 0;
}

int nf_flow_rule_route_ipv4(struct net *net, const struct flow_offload *flow,
                            enum flow_offload_tuple_dir dir,
                            struct nf_flow_rule *flow_rule)
{
        if (nf_flow_rule_route_common(net, flow, dir, flow_rule) < 0)
                return -1;

        if (test_bit(NF_FLOW_SNAT, &flow->flags)) {
                flow_offload_ipv4_snat(net, flow, dir, flow_rule);
                flow_offload_port_snat(net, flow, dir, flow_rule);
        }
        if (test_bit(NF_FLOW_DNAT, &flow->flags)) {
                flow_offload_ipv4_dnat(net, flow, dir, flow_rule);
                flow_offload_port_dnat(net, flow, dir, flow_rule);
        }
        if (test_bit(NF_FLOW_SNAT, &flow->flags) ||
            test_bit(NF_FLOW_DNAT, &flow->flags))
                flow_offload_ipv4_checksum(net, flow, flow_rule);

        flow_offload_redirect(net, flow, dir, flow_rule);

        return 0;
}
EXPORT_SYMBOL_GPL(nf_flow_rule_route_ipv4);

int nf_flow_rule_route_ipv6(struct net *net, const struct flow_offload *flow,
                            enum flow_offload_tuple_dir dir,
                            struct nf_flow_rule *flow_rule)
{
        if (nf_flow_rule_route_common(net, flow, dir, flow_rule) < 0)
                return -1;

        if (test_bit(NF_FLOW_SNAT, &flow->flags)) {
                flow_offload_ipv6_snat(net, flow, dir, flow_rule);
                flow_offload_port_snat(net, flow, dir, flow_rule);
        }
        if (test_bit(NF_FLOW_DNAT, &flow->flags)) {
                flow_offload_ipv6_dnat(net, flow, dir, flow_rule);
                flow_offload_port_dnat(net, flow, dir, flow_rule);
        }

        flow_offload_redirect(net, flow, dir, flow_rule);

        return 0;
}
EXPORT_SYMBOL_GPL(nf_flow_rule_route_ipv6);

#define NF_FLOW_RULE_ACTION_MAX 16

static struct nf_flow_rule *
nf_flow_offload_rule_alloc(struct net *net,
                           const struct flow_offload_work *offload,
                           enum flow_offload_tuple_dir dir)
{
        const struct nf_flowtable *flowtable = offload->flowtable;
        const struct flow_offload_tuple *tuple, *other_tuple;
        const struct flow_offload *flow = offload->flow;
        struct dst_entry *other_dst = NULL;
        struct nf_flow_rule *flow_rule;
        int err = -ENOMEM;

        flow_rule = kzalloc(sizeof(*flow_rule), GFP_KERNEL);
        if (!flow_rule)
                goto err_flow;

        flow_rule->rule = flow_rule_alloc(NF_FLOW_RULE_ACTION_MAX);
        if (!flow_rule->rule)
                goto err_flow_rule;

        flow_rule->rule->match.dissector = &flow_rule->match.dissector;
        flow_rule->rule->match.mask = &flow_rule->match.mask;
        flow_rule->rule->match.key = &flow_rule->match.key;

        tuple = &flow->tuplehash[dir].tuple;
        other_tuple = &flow->tuplehash[!dir].tuple;
        if (other_tuple->xmit_type == FLOW_OFFLOAD_XMIT_NEIGH)
                other_dst = other_tuple->dst_cache;

        err = nf_flow_rule_match(&flow_rule->match, tuple, other_dst);
        if (err < 0)
                goto err_flow_match;

        flow_rule->rule->action.num_entries = 0;
        if (flowtable->type->action(net, flow, dir, flow_rule) < 0)
                goto err_flow_match;

        return flow_rule;

err_flow_match:
        kfree(flow_rule->rule);
err_flow_rule:
        kfree(flow_rule);
err_flow:
        return NULL;
}

static void __nf_flow_offload_destroy(struct nf_flow_rule *flow_rule)
{
        struct flow_action_entry *entry;
        int i;

        for (i = 0; i < flow_rule->rule->action.num_entries; i++) {
                entry = &flow_rule->rule->action.entries[i];
                if (entry->id != FLOW_ACTION_REDIRECT)
                        continue;

                dev_put(entry->dev);
        }
        kfree(flow_rule->rule);
        kfree(flow_rule);
}

static void nf_flow_offload_destroy(struct nf_flow_rule *flow_rule[])
{
        int i;

        for (i = 0; i < FLOW_OFFLOAD_DIR_MAX; i++)
                __nf_flow_offload_destroy(flow_rule[i]);
}

static int nf_flow_offload_alloc(const struct flow_offload_work *offload,
                                 struct nf_flow_rule *flow_rule[])
{
        struct net *net = read_pnet(&offload->flowtable->net);

        flow_rule[0] = nf_flow_offload_rule_alloc(net, offload,
                                                  FLOW_OFFLOAD_DIR_ORIGINAL);
        if (!flow_rule[0])
                return -ENOMEM;

        flow_rule[1] = nf_flow_offload_rule_alloc(net, offload,
                                                  FLOW_OFFLOAD_DIR_REPLY);
        if (!flow_rule[1]) {
                __nf_flow_offload_destroy(flow_rule[0]);
                return -ENOMEM;
        }

        return 0;
}

static void nf_flow_offload_init(struct flow_cls_offload *cls_flow,
                                 __be16 proto, int priority,
                                 enum flow_cls_command cmd,
                                 const struct flow_offload_tuple *tuple,
                                 struct netlink_ext_ack *extack)
{
        cls_flow->common.protocol = proto;
        cls_flow->common.prio = priority;
        cls_flow->common.extack = extack;
        cls_flow->command = cmd;
        cls_flow->cookie = (unsigned long)tuple;
}

static int nf_flow_offload_tuple(struct nf_flowtable *flowtable,
                                 struct flow_offload *flow,
                                 struct nf_flow_rule *flow_rule,
                                 enum flow_offload_tuple_dir dir,
                                 int priority, int cmd,
                                 struct flow_stats *stats,
                                 struct list_head *block_cb_list)
{
        struct flow_cls_offload cls_flow = {};
        struct flow_block_cb *block_cb;
        struct netlink_ext_ack extack;
        __be16 proto = ETH_P_ALL;
        int err, i = 0;

        nf_flow_offload_init(&cls_flow, proto, priority, cmd,
                             &flow->tuplehash[dir].tuple, &extack);
        if (cmd == FLOW_CLS_REPLACE)
                cls_flow.rule = flow_rule->rule;

        down_read(&flowtable->flow_block_lock);
        list_for_each_entry(block_cb, block_cb_list, list) {
                err = block_cb->cb(TC_SETUP_CLSFLOWER, &cls_flow,
                                   block_cb->cb_priv);
                if (err < 0)
                        continue;

                i++;
        }
        up_read(&flowtable->flow_block_lock);

        if (cmd == FLOW_CLS_STATS)
                memcpy(stats, &cls_flow.stats, sizeof(*stats));

        return i;
}

static int flow_offload_tuple_add(struct flow_offload_work *offload,
                                  struct nf_flow_rule *flow_rule,
                                  enum flow_offload_tuple_dir dir)
{
        return nf_flow_offload_tuple(offload->flowtable, offload->flow,
                                     flow_rule, dir, offload->priority,
                                     FLOW_CLS_REPLACE, NULL,
                                     &offload->flowtable->flow_block.cb_list);
}

static void flow_offload_tuple_del(struct flow_offload_work *offload,
                                   enum flow_offload_tuple_dir dir)
{
        nf_flow_offload_tuple(offload->flowtable, offload->flow, NULL, dir,
                              offload->priority, FLOW_CLS_DESTROY, NULL,
                              &offload->flowtable->flow_block.cb_list);
}

static int flow_offload_rule_add(struct flow_offload_work *offload,
                                 struct nf_flow_rule *flow_rule[])
{
        int ok_count = 0;

        ok_count += flow_offload_tuple_add(offload, flow_rule[0],
                                           FLOW_OFFLOAD_DIR_ORIGINAL);
        ok_count += flow_offload_tuple_add(offload, flow_rule[1],
                                           FLOW_OFFLOAD_DIR_REPLY);
        if (ok_count == 0)
                return -ENOENT;

        return 0;
}

static void flow_offload_work_add(struct flow_offload_work *offload)
{
        struct nf_flow_rule *flow_rule[FLOW_OFFLOAD_DIR_MAX];
        int err;

        err = nf_flow_offload_alloc(offload, flow_rule);
        if (err < 0)
                return;

        err = flow_offload_rule_add(offload, flow_rule);
        if (err < 0)
                goto out;

        set_bit(IPS_HW_OFFLOAD_BIT, &offload->flow->ct->status);

out:
        nf_flow_offload_destroy(flow_rule);
}

static void flow_offload_work_del(struct flow_offload_work *offload)
{
        clear_bit(IPS_HW_OFFLOAD_BIT, &offload->flow->ct->status);
        flow_offload_tuple_del(offload, FLOW_OFFLOAD_DIR_ORIGINAL);
        flow_offload_tuple_del(offload, FLOW_OFFLOAD_DIR_REPLY);
        set_bit(NF_FLOW_HW_DEAD, &offload->flow->flags);
}

static void flow_offload_tuple_stats(struct flow_offload_work *offload,
                                     enum flow_offload_tuple_dir dir,
                                     struct flow_stats *stats)
{
        nf_flow_offload_tuple(offload->flowtable, offload->flow, NULL, dir,
                              offload->priority, FLOW_CLS_STATS, stats,
                              &offload->flowtable->flow_block.cb_list);
}

static void flow_offload_work_stats(struct flow_offload_work *offload)
{
        struct flow_stats stats[FLOW_OFFLOAD_DIR_MAX] = {};
        u64 lastused;

        flow_offload_tuple_stats(offload, FLOW_OFFLOAD_DIR_ORIGINAL, &stats[0]);
        flow_offload_tuple_stats(offload, FLOW_OFFLOAD_DIR_REPLY, &stats[1]);

        lastused = max_t(u64, stats[0].lastused, stats[1].lastused);
        offload->flow->timeout = max_t(u64, offload->flow->timeout,
                                       lastused + flow_offload_get_timeout(offload->flow));

        if (offload->flowtable->flags & NF_FLOWTABLE_COUNTER) {
                if (stats[0].pkts)
                        nf_ct_acct_add(offload->flow->ct,
                                       FLOW_OFFLOAD_DIR_ORIGINAL,
                                       stats[0].pkts, stats[0].bytes);
                if (stats[1].pkts)
                        nf_ct_acct_add(offload->flow->ct,
                                       FLOW_OFFLOAD_DIR_REPLY,
                                       stats[1].pkts, stats[1].bytes);
        }
}

static void flow_offload_work_handler(struct work_struct *work)
{
        struct flow_offload_work *offload;

        offload = container_of(work, struct flow_offload_work, work);
        switch (offload->cmd) {
                case FLOW_CLS_REPLACE:
                        flow_offload_work_add(offload);
                        break;
                case FLOW_CLS_DESTROY:
                        flow_offload_work_del(offload);
                        break;
                case FLOW_CLS_STATS:
                        flow_offload_work_stats(offload);
                        break;
                default:
                        WARN_ON_ONCE(1);
        }

        clear_bit(NF_FLOW_HW_PENDING, &offload->flow->flags);
        kfree(offload);
}

static void flow_offload_queue_work(struct flow_offload_work *offload)
{
        if (offload->cmd == FLOW_CLS_REPLACE)
                queue_work(nf_flow_offload_add_wq, &offload->work);
        else if (offload->cmd == FLOW_CLS_DESTROY)
                queue_work(nf_flow_offload_del_wq, &offload->work);
        else
                queue_work(nf_flow_offload_stats_wq, &offload->work);
}

static struct flow_offload_work *
nf_flow_offload_work_alloc(struct nf_flowtable *flowtable,
                           struct flow_offload *flow, unsigned int cmd)
{
        struct flow_offload_work *offload;

        if (test_and_set_bit(NF_FLOW_HW_PENDING, &flow->flags))
                return NULL;

        offload = kmalloc(sizeof(struct flow_offload_work), GFP_ATOMIC);
        if (!offload) {
                clear_bit(NF_FLOW_HW_PENDING, &flow->flags);
                return NULL;
        }

        offload->cmd = cmd;
        offload->flow = flow;
        offload->priority = flowtable->priority;
        offload->flowtable = flowtable;
        INIT_WORK(&offload->work, flow_offload_work_handler);

        return offload;
}


void nf_flow_offload_add(struct nf_flowtable *flowtable,
                         struct flow_offload *flow)
{
        struct flow_offload_work *offload;

        offload = nf_flow_offload_work_alloc(flowtable, flow, FLOW_CLS_REPLACE);
        if (!offload)
                return;

        flow_offload_queue_work(offload);
}

void nf_flow_offload_del(struct nf_flowtable *flowtable,
                         struct flow_offload *flow)
{
        struct flow_offload_work *offload;

        offload = nf_flow_offload_work_alloc(flowtable, flow, FLOW_CLS_DESTROY);
        if (!offload)
                return;

        set_bit(NF_FLOW_HW_DYING, &flow->flags);
        flow_offload_queue_work(offload);
}

void nf_flow_offload_stats(struct nf_flowtable *flowtable,
                           struct flow_offload *flow)
{
        struct flow_offload_work *offload;
        __s32 delta;

        delta = nf_flow_timeout_delta(flow->timeout);
        if ((delta >= (9 * flow_offload_get_timeout(flow)) / 10))
                return;

        offload = nf_flow_offload_work_alloc(flowtable, flow, FLOW_CLS_STATS);
        if (!offload)
                return;

        flow_offload_queue_work(offload);
}

void nf_flow_table_offload_flush(struct nf_flowtable *flowtable)
{
        if (nf_flowtable_hw_offload(flowtable)) {
                flush_workqueue(nf_flow_offload_add_wq);
                flush_workqueue(nf_flow_offload_del_wq);
                flush_workqueue(nf_flow_offload_stats_wq);
        }
}

static int nf_flow_table_block_setup(struct nf_flowtable *flowtable,
                                     struct flow_block_offload *bo,
                                     enum flow_block_command cmd)
{
        struct flow_block_cb *block_cb, *next;
        int err = 0;

        switch (cmd) {
        case FLOW_BLOCK_BIND:
                list_splice(&bo->cb_list, &flowtable->flow_block.cb_list);
                break;
        case FLOW_BLOCK_UNBIND:
                list_for_each_entry_safe(block_cb, next, &bo->cb_list, list) {
                        list_del(&block_cb->list);
                        flow_block_cb_free(block_cb);
                }
                break;
        default:
                WARN_ON_ONCE(1);
                err = -EOPNOTSUPP;
        }

        return err;
}

static void nf_flow_table_block_offload_init(struct flow_block_offload *bo,
                                             struct net *net,
                                             enum flow_block_command cmd,
                                             struct nf_flowtable *flowtable,
                                             struct netlink_ext_ack *extack)
{
        memset(bo, 0, sizeof(*bo));
        bo->net         = net;
        bo->block       = &flowtable->flow_block;
        bo->command     = cmd;
        bo->binder_type = FLOW_BLOCK_BINDER_TYPE_CLSACT_INGRESS;
        bo->extack      = extack;
        bo->cb_list_head = &flowtable->flow_block.cb_list;
        INIT_LIST_HEAD(&bo->cb_list);
}

static void nf_flow_table_indr_cleanup(struct flow_block_cb *block_cb)
{
        struct nf_flowtable *flowtable = block_cb->indr.data;
        struct net_device *dev = block_cb->indr.dev;

        nf_flow_table_gc_cleanup(flowtable, dev);
        down_write(&flowtable->flow_block_lock);
        list_del(&block_cb->list);
        list_del(&block_cb->driver_list);
        flow_block_cb_free(block_cb);
        up_write(&flowtable->flow_block_lock);
}

static int nf_flow_table_indr_offload_cmd(struct flow_block_offload *bo,
                                          struct nf_flowtable *flowtable,
                                          struct net_device *dev,
                                          enum flow_block_command cmd,
                                          struct netlink_ext_ack *extack)
{
        nf_flow_table_block_offload_init(bo, dev_net(dev), cmd, flowtable,
                                         extack);

        return flow_indr_dev_setup_offload(dev, NULL, TC_SETUP_FT, flowtable, bo,
                                           nf_flow_table_indr_cleanup);
}

static int nf_flow_table_offload_cmd(struct flow_block_offload *bo,
                                     struct nf_flowtable *flowtable,
                                     struct net_device *dev,
                                     enum flow_block_command cmd,
                                     struct netlink_ext_ack *extack)
{
        int err;

        nf_flow_table_block_offload_init(bo, dev_net(dev), cmd, flowtable,
                                         extack);
        err = dev->netdev_ops->ndo_setup_tc(dev, TC_SETUP_FT, bo);
        if (err < 0)
                return err;

        return 0;
}

int nf_flow_table_offload_setup(struct nf_flowtable *flowtable,
                                struct net_device *dev,
                                enum flow_block_command cmd)
{
        struct netlink_ext_ack extack = {};
        struct flow_block_offload bo;
        int err;

        if (!nf_flowtable_hw_offload(flowtable))
                return 0;

        if (dev->netdev_ops->ndo_setup_tc)
                err = nf_flow_table_offload_cmd(&bo, flowtable, dev, cmd,
                                                &extack);
        else
                err = nf_flow_table_indr_offload_cmd(&bo, flowtable, dev, cmd,
                                                     &extack);
        if (err < 0)
                return err;

        return nf_flow_table_block_setup(flowtable, &bo, cmd);
}
EXPORT_SYMBOL_GPL(nf_flow_table_offload_setup);

int nf_flow_table_offload_init(void)
{
        nf_flow_offload_add_wq  = alloc_workqueue("nf_ft_offload_add",
                                                  WQ_UNBOUND | WQ_SYSFS, 0);
        if (!nf_flow_offload_add_wq)
                return -ENOMEM;

        nf_flow_offload_del_wq  = alloc_workqueue("nf_ft_offload_del",
                                                  WQ_UNBOUND | WQ_SYSFS, 0);
        if (!nf_flow_offload_del_wq)
                goto err_del_wq;

        nf_flow_offload_stats_wq  = alloc_workqueue("nf_ft_offload_stats",
                                                    WQ_UNBOUND | WQ_SYSFS, 0);
        if (!nf_flow_offload_stats_wq)
                goto err_stats_wq;

        return 0;

err_stats_wq:
        destroy_workqueue(nf_flow_offload_del_wq);
err_del_wq:
        destroy_workqueue(nf_flow_offload_add_wq);
        return -ENOMEM;
}

void nf_flow_table_offload_exit(void)
{
        destroy_workqueue(nf_flow_offload_add_wq);
        destroy_workqueue(nf_flow_offload_del_wq);
        destroy_workqueue(nf_flow_offload_stats_wq);
}