netfilter: bridge: make sure to pull arp header in br_nf_forward_arp()

[mirror_ubuntu-bionic-kernel.git] / net / bridge / br_private.h

/*
 *      Linux ethernet bridge
 *
 *      Authors:
 *      Lennert Buytenhek               <buytenh@gnu.org>
 *
 *      This program is free software; you can redistribute it and/or
 *      modify it under the terms of the GNU General Public License
 *      as published by the Free Software Foundation; either version
 *      2 of the License, or (at your option) any later version.
 */

#ifndef _BR_PRIVATE_H
#define _BR_PRIVATE_H

#include <linux/netdevice.h>
#include <linux/if_bridge.h>
#include <linux/netpoll.h>
#include <linux/u64_stats_sync.h>
#include <net/route.h>
#include <net/ip6_fib.h>
#include <linux/if_vlan.h>
#include <linux/rhashtable.h>
#include <linux/refcount.h>

#define BR_HASH_BITS 8
#define BR_HASH_SIZE (1 << BR_HASH_BITS)

#define BR_HOLD_TIME (1*HZ)

#define BR_PORT_BITS    10
#define BR_MAX_PORTS    (1<<BR_PORT_BITS)

#define BR_VERSION      "2.3"

/* Control of forwarding link local multicast */
#define BR_GROUPFWD_DEFAULT     0
/* Don't allow forwarding of control protocols like STP, MAC PAUSE and LACP */
enum {
        BR_GROUPFWD_STP         = BIT(0),
        BR_GROUPFWD_MACPAUSE    = BIT(1),
        BR_GROUPFWD_LACP        = BIT(2),
};

#define BR_GROUPFWD_RESTRICTED (BR_GROUPFWD_STP | BR_GROUPFWD_MACPAUSE | \
                                BR_GROUPFWD_LACP)
/* The Nearest Customer Bridge Group Address, 01-80-C2-00-00-[00,0B,0C,0D,0F] */
#define BR_GROUPFWD_8021AD      0xB801u

/* Path to usermode spanning tree program */
#define BR_STP_PROG     "/sbin/bridge-stp"

typedef struct bridge_id bridge_id;
typedef struct mac_addr mac_addr;
typedef __u16 port_id;

struct bridge_id
{
        unsigned char   prio[2];
        unsigned char   addr[ETH_ALEN];
};

struct mac_addr
{
        unsigned char   addr[ETH_ALEN];
};

#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
/* our own querier */
struct bridge_mcast_own_query {
        struct timer_list       timer;
        u32                     startup_sent;
};

/* other querier */
struct bridge_mcast_other_query {
        struct timer_list               timer;
        unsigned long                   delay_time;
};

/* selected querier */
struct bridge_mcast_querier {
        struct br_ip addr;
        struct net_bridge_port __rcu    *port;
};

/* IGMP/MLD statistics */
struct bridge_mcast_stats {
        struct br_mcast_stats mstats;
        struct u64_stats_sync syncp;
};
#endif

struct br_vlan_stats {
        u64 rx_bytes;
        u64 rx_packets;
        u64 tx_bytes;
        u64 tx_packets;
        struct u64_stats_sync syncp;
};

struct br_tunnel_info {
        __be64                  tunnel_id;
        struct metadata_dst     *tunnel_dst;
};

/**
 * struct net_bridge_vlan - per-vlan entry
 *
 * @vnode: rhashtable member
 * @vid: VLAN id
 * @flags: bridge vlan flags
 * @stats: per-cpu VLAN statistics
 * @br: if MASTER flag set, this points to a bridge struct
 * @port: if MASTER flag unset, this points to a port struct
 * @refcnt: if MASTER flag set, this is bumped for each port referencing it
 * @brvlan: if MASTER flag unset, this points to the global per-VLAN context
 *          for this VLAN entry
 * @vlist: sorted list of VLAN entries
 * @rcu: used for entry destruction
 *
 * This structure is shared between the global per-VLAN entries contained in
 * the bridge rhashtable and the local per-port per-VLAN entries contained in
 * the port's rhashtable. The union entries should be interpreted depending on
 * the entry flags that are set.
 */
struct net_bridge_vlan {
        struct rhash_head               vnode;
        struct rhash_head               tnode;
        u16                             vid;
        u16                             flags;
        struct br_vlan_stats __percpu   *stats;
        union {
                struct net_bridge       *br;
                struct net_bridge_port  *port;
        };
        union {
                refcount_t              refcnt;
                struct net_bridge_vlan  *brvlan;
        };

        struct br_tunnel_info           tinfo;

        struct list_head                vlist;

        struct rcu_head                 rcu;
};

/**
 * struct net_bridge_vlan_group
 *
 * @vlan_hash: VLAN entry rhashtable
 * @vlan_list: sorted VLAN entry list
 * @num_vlans: number of total VLAN entries
 * @pvid: PVID VLAN id
 *
 * IMPORTANT: Be careful when checking if there're VLAN entries using list
 *            primitives because the bridge can have entries in its list which
 *            are just for global context but not for filtering, i.e. they have
 *            the master flag set but not the brentry flag. If you have to check
 *            if there're "real" entries in the bridge please test @num_vlans
 */
struct net_bridge_vlan_group {
        struct rhashtable               vlan_hash;
        struct rhashtable               tunnel_hash;
        struct list_head                vlan_list;
        u16                             num_vlans;
        u16                             pvid;
};

struct net_bridge_fdb_entry {
        struct hlist_node               hlist;
        struct net_bridge_port          *dst;

        mac_addr                        addr;
        __u16                           vlan_id;
        unsigned char                   is_local:1,
                                        is_static:1,
                                        added_by_user:1,
                                        added_by_external_learn:1,
                                        offloaded:1;

        /* write-heavy members should not affect lookups */
        unsigned long                   updated ____cacheline_aligned_in_smp;
        unsigned long                   used;

        struct rcu_head                 rcu;
};

#define MDB_PG_FLAGS_PERMANENT  BIT(0)
#define MDB_PG_FLAGS_OFFLOAD    BIT(1)

struct net_bridge_port_group {
        struct net_bridge_port          *port;
        struct net_bridge_port_group __rcu *next;
        struct hlist_node               mglist;
        struct rcu_head                 rcu;
        struct timer_list               timer;
        struct br_ip                    addr;
        unsigned char                   flags;
        unsigned char                   eth_addr[ETH_ALEN];
};

struct net_bridge_mdb_entry
{
        struct hlist_node               hlist[2];
        struct net_bridge               *br;
        struct net_bridge_port_group __rcu *ports;
        struct rcu_head                 rcu;
        struct timer_list               timer;
        struct br_ip                    addr;
        bool                            host_joined;
};

struct net_bridge_mdb_htable
{
        struct hlist_head               *mhash;
        struct rcu_head                 rcu;
        struct net_bridge_mdb_htable    *old;
        u32                             size;
        u32                             max;
        u32                             secret;
        u32                             ver;
};

struct net_bridge_port {
        struct net_bridge               *br;
        struct net_device               *dev;
        struct list_head                list;

        unsigned long                   flags;
#ifdef CONFIG_BRIDGE_VLAN_FILTERING
        struct net_bridge_vlan_group    __rcu *vlgrp;
#endif

        /* STP */
        u8                              priority;
        u8                              state;
        u16                             port_no;
        unsigned char                   topology_change_ack;
        unsigned char                   config_pending;
        port_id                         port_id;
        port_id                         designated_port;
        bridge_id                       designated_root;
        bridge_id                       designated_bridge;
        u32                             path_cost;
        u32                             designated_cost;
        unsigned long                   designated_age;

        struct timer_list               forward_delay_timer;
        struct timer_list               hold_timer;
        struct timer_list               message_age_timer;
        struct kobject                  kobj;
        struct rcu_head                 rcu;

#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
        struct bridge_mcast_own_query   ip4_own_query;
#if IS_ENABLED(CONFIG_IPV6)
        struct bridge_mcast_own_query   ip6_own_query;
#endif /* IS_ENABLED(CONFIG_IPV6) */
        unsigned char                   multicast_router;
        struct bridge_mcast_stats       __percpu *mcast_stats;
        struct timer_list               multicast_router_timer;
        struct hlist_head               mglist;
        struct hlist_node               rlist;
#endif

#ifdef CONFIG_SYSFS
        char                            sysfs_name[IFNAMSIZ];
#endif

#ifdef CONFIG_NET_POLL_CONTROLLER
        struct netpoll                  *np;
#endif
#ifdef CONFIG_NET_SWITCHDEV
        int                             offload_fwd_mark;
#endif
        u16                             group_fwd_mask;
};

#define kobj_to_brport(obj)     container_of(obj, struct net_bridge_port, kobj)

#define br_auto_port(p) ((p)->flags & BR_AUTO_MASK)
#define br_promisc_port(p) ((p)->flags & BR_PROMISC)

#define br_port_exists(dev) (dev->priv_flags & IFF_BRIDGE_PORT)

static inline struct net_bridge_port *br_port_get_rcu(const struct net_device *dev)
{
        return rcu_dereference(dev->rx_handler_data);
}

static inline struct net_bridge_port *br_port_get_rtnl(const struct net_device *dev)
{
        return br_port_exists(dev) ?
                rtnl_dereference(dev->rx_handler_data) : NULL;
}

static inline struct net_bridge_port *br_port_get_rtnl_rcu(const struct net_device *dev)
{
        return br_port_exists(dev) ?
                rcu_dereference_rtnl(dev->rx_handler_data) : NULL;
}

enum net_bridge_opts {
        BROPT_VLAN_ENABLED,
        BROPT_VLAN_STATS_ENABLED,
        BROPT_NF_CALL_IPTABLES,
        BROPT_NF_CALL_IP6TABLES,
        BROPT_NF_CALL_ARPTABLES,
};

struct net_bridge {
        spinlock_t                      lock;
        spinlock_t                      hash_lock;
        struct list_head                port_list;
        struct net_device               *dev;
        struct pcpu_sw_netstats         __percpu *stats;
        unsigned long                   options;
        /* These fields are accessed on each packet */
#ifdef CONFIG_BRIDGE_VLAN_FILTERING
        __be16                          vlan_proto;
        u16                             default_pvid;
        struct net_bridge_vlan_group    __rcu *vlgrp;
#endif

        struct hlist_head               hash[BR_HASH_SIZE];
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
        union {
                struct rtable           fake_rtable;
                struct rt6_info         fake_rt6_info;
        };
#endif
        u16                             group_fwd_mask;
        u16                             group_fwd_mask_required;

        /* STP */
        bridge_id                       designated_root;
        bridge_id                       bridge_id;
        u32                             root_path_cost;
        unsigned char                   topology_change;
        unsigned char                   topology_change_detected;
        u16                             root_port;
        unsigned long                   max_age;
        unsigned long                   hello_time;
        unsigned long                   forward_delay;
        unsigned long                   ageing_time;
        unsigned long                   bridge_max_age;
        unsigned long                   bridge_hello_time;
        unsigned long                   bridge_forward_delay;
        unsigned long                   bridge_ageing_time;

        u8                              group_addr[ETH_ALEN];
        bool                            group_addr_set;

        enum {
                BR_NO_STP,              /* no spanning tree */
                BR_KERNEL_STP,          /* old STP in kernel */
                BR_USER_STP,            /* new RSTP in userspace */
        } stp_enabled;

#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
        unsigned char                   multicast_router;

        u8                              multicast_disabled:1;
        u8                              multicast_querier:1;
        u8                              multicast_query_use_ifaddr:1;
        u8                              has_ipv6_addr:1;
        u8                              multicast_stats_enabled:1;

        u32                             hash_elasticity;
        u32                             hash_max;

        u32                             multicast_last_member_count;
        u32                             multicast_startup_query_count;

        u8                              multicast_igmp_version;

        unsigned long                   multicast_last_member_interval;
        unsigned long                   multicast_membership_interval;
        unsigned long                   multicast_querier_interval;
        unsigned long                   multicast_query_interval;
        unsigned long                   multicast_query_response_interval;
        unsigned long                   multicast_startup_query_interval;

        spinlock_t                      multicast_lock;
        struct net_bridge_mdb_htable __rcu *mdb;
        struct hlist_head               router_list;

        struct timer_list               multicast_router_timer;
        struct bridge_mcast_other_query ip4_other_query;
        struct bridge_mcast_own_query   ip4_own_query;
        struct bridge_mcast_querier     ip4_querier;
        struct bridge_mcast_stats       __percpu *mcast_stats;
#if IS_ENABLED(CONFIG_IPV6)
        struct bridge_mcast_other_query ip6_other_query;
        struct bridge_mcast_own_query   ip6_own_query;
        struct bridge_mcast_querier     ip6_querier;
        u8                              multicast_mld_version;
#endif /* IS_ENABLED(CONFIG_IPV6) */
#endif

        struct timer_list               hello_timer;
        struct timer_list               tcn_timer;
        struct timer_list               topology_change_timer;
        struct delayed_work             gc_work;
        struct kobject                  *ifobj;
        u32                             auto_cnt;

#ifdef CONFIG_NET_SWITCHDEV
        int offload_fwd_mark;
#endif
        bool                            neigh_suppress_enabled;
};

struct br_input_skb_cb {
        struct net_device *brdev;

#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
        int igmp;
        int mrouters_only;
#endif

        bool proxyarp_replied;

#ifdef CONFIG_BRIDGE_VLAN_FILTERING
        bool vlan_filtered;
#endif

#ifdef CONFIG_NET_SWITCHDEV
        int offload_fwd_mark;
#endif
};

#define BR_INPUT_SKB_CB(__skb)  ((struct br_input_skb_cb *)(__skb)->cb)

#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
# define BR_INPUT_SKB_CB_MROUTERS_ONLY(__skb)   (BR_INPUT_SKB_CB(__skb)->mrouters_only)
#else
# define BR_INPUT_SKB_CB_MROUTERS_ONLY(__skb)   (0)
#endif

#define br_printk(level, br, format, args...)   \
        printk(level "%s: " format, (br)->dev->name, ##args)

#define br_err(__br, format, args...)                   \
        br_printk(KERN_ERR, __br, format, ##args)
#define br_warn(__br, format, args...)                  \
        br_printk(KERN_WARNING, __br, format, ##args)
#define br_notice(__br, format, args...)                \
        br_printk(KERN_NOTICE, __br, format, ##args)
#define br_info(__br, format, args...)                  \
        br_printk(KERN_INFO, __br, format, ##args)

#define br_debug(br, format, args...)                   \
        pr_debug("%s: " format,  (br)->dev->name, ##args)

/* called under bridge lock */
static inline int br_is_root_bridge(const struct net_bridge *br)
{
        return !memcmp(&br->bridge_id, &br->designated_root, 8);
}

/* check if a VLAN entry is global */
static inline bool br_vlan_is_master(const struct net_bridge_vlan *v)
{
        return v->flags & BRIDGE_VLAN_INFO_MASTER;
}

/* check if a VLAN entry is used by the bridge */
static inline bool br_vlan_is_brentry(const struct net_bridge_vlan *v)
{
        return v->flags & BRIDGE_VLAN_INFO_BRENTRY;
}

/* check if we should use the vlan entry, returns false if it's only context */
static inline bool br_vlan_should_use(const struct net_bridge_vlan *v)
{
        if (br_vlan_is_master(v)) {
                if (br_vlan_is_brentry(v))
                        return true;
                else
                        return false;
        }

        return true;
}

static inline int br_opt_get(const struct net_bridge *br,
                             enum net_bridge_opts opt)
{
        return test_bit(opt, &br->options);
}

void br_opt_toggle(struct net_bridge *br, enum net_bridge_opts opt, bool on);

/* br_device.c */
void br_dev_setup(struct net_device *dev);
void br_dev_delete(struct net_device *dev, struct list_head *list);
netdev_tx_t br_dev_xmit(struct sk_buff *skb, struct net_device *dev);
#ifdef CONFIG_NET_POLL_CONTROLLER
static inline void br_netpoll_send_skb(const struct net_bridge_port *p,
                                       struct sk_buff *skb)
{
        struct netpoll *np = p->np;

        if (np)
                netpoll_send_skb(np, skb);
}

int br_netpoll_enable(struct net_bridge_port *p);
void br_netpoll_disable(struct net_bridge_port *p);
#else
static inline void br_netpoll_send_skb(const struct net_bridge_port *p,
                                       struct sk_buff *skb)
{
}

static inline int br_netpoll_enable(struct net_bridge_port *p)
{
        return 0;
}

static inline void br_netpoll_disable(struct net_bridge_port *p)
{
}
#endif

/* br_fdb.c */
int br_fdb_init(void);
void br_fdb_fini(void);
void br_fdb_flush(struct net_bridge *br);
void br_fdb_find_delete_local(struct net_bridge *br,
                              const struct net_bridge_port *p,
                              const unsigned char *addr, u16 vid);
void br_fdb_changeaddr(struct net_bridge_port *p, const unsigned char *newaddr);
void br_fdb_change_mac_address(struct net_bridge *br, const u8 *newaddr);
void br_fdb_cleanup(struct work_struct *work);
void br_fdb_delete_by_port(struct net_bridge *br,
                           const struct net_bridge_port *p, u16 vid, int do_all);
struct net_bridge_fdb_entry *br_fdb_find_rcu(struct net_bridge *br,
                                             const unsigned char *addr,
                                             __u16 vid);
int br_fdb_test_addr(struct net_device *dev, unsigned char *addr);
int br_fdb_fillbuf(struct net_bridge *br, void *buf, unsigned long count,
                   unsigned long off);
int br_fdb_insert(struct net_bridge *br, struct net_bridge_port *source,
                  const unsigned char *addr, u16 vid);
void br_fdb_update(struct net_bridge *br, struct net_bridge_port *source,
                   const unsigned char *addr, u16 vid, bool added_by_user);

int br_fdb_delete(struct ndmsg *ndm, struct nlattr *tb[],
                  struct net_device *dev, const unsigned char *addr, u16 vid);
int br_fdb_add(struct ndmsg *nlh, struct nlattr *tb[], struct net_device *dev,
               const unsigned char *addr, u16 vid, u16 nlh_flags);
int br_fdb_dump(struct sk_buff *skb, struct netlink_callback *cb,
                struct net_device *dev, struct net_device *fdev, int *idx);
int br_fdb_sync_static(struct net_bridge *br, struct net_bridge_port *p);
void br_fdb_unsync_static(struct net_bridge *br, struct net_bridge_port *p);
int br_fdb_external_learn_add(struct net_bridge *br, struct net_bridge_port *p,
                              const unsigned char *addr, u16 vid);
int br_fdb_external_learn_del(struct net_bridge *br, struct net_bridge_port *p,
                              const unsigned char *addr, u16 vid);
void br_fdb_offloaded_set(struct net_bridge *br, struct net_bridge_port *p,
                          const unsigned char *addr, u16 vid);

/* br_forward.c */
enum br_pkt_type {
        BR_PKT_UNICAST,
        BR_PKT_MULTICAST,
        BR_PKT_BROADCAST
};
int br_dev_queue_push_xmit(struct net *net, struct sock *sk, struct sk_buff *skb);
void br_forward(const struct net_bridge_port *to, struct sk_buff *skb,
                bool local_rcv, bool local_orig);
int br_forward_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
void br_flood(struct net_bridge *br, struct sk_buff *skb,
              enum br_pkt_type pkt_type, bool local_rcv, bool local_orig);

/* br_if.c */
void br_port_carrier_check(struct net_bridge_port *p);
int br_add_bridge(struct net *net, const char *name);
int br_del_bridge(struct net *net, const char *name);
int br_add_if(struct net_bridge *br, struct net_device *dev,
              struct netlink_ext_ack *extack);
int br_del_if(struct net_bridge *br, struct net_device *dev);
int br_min_mtu(const struct net_bridge *br);
netdev_features_t br_features_recompute(struct net_bridge *br,
                                        netdev_features_t features);
void br_port_flags_change(struct net_bridge_port *port, unsigned long mask);
void br_manage_promisc(struct net_bridge *br);

/* br_input.c */
int br_handle_frame_finish(struct net *net, struct sock *sk, struct sk_buff *skb);
rx_handler_result_t br_handle_frame(struct sk_buff **pskb);

static inline bool br_rx_handler_check_rcu(const struct net_device *dev)
{
        return rcu_dereference(dev->rx_handler) == br_handle_frame;
}

static inline struct net_bridge_port *br_port_get_check_rcu(const struct net_device *dev)
{
        return br_rx_handler_check_rcu(dev) ? br_port_get_rcu(dev) : NULL;
}

/* br_ioctl.c */
int br_dev_ioctl(struct net_device *dev, struct ifreq *rq, int cmd);
int br_ioctl_deviceless_stub(struct net *net, unsigned int cmd,
                             void __user *arg);

/* br_multicast.c */
#ifdef CONFIG_BRIDGE_IGMP_SNOOPING
extern unsigned int br_mdb_rehash_seq;
int br_multicast_rcv(struct net_bridge *br, struct net_bridge_port *port,
                     struct sk_buff *skb, u16 vid);
struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
                                        struct sk_buff *skb, u16 vid);
int br_multicast_add_port(struct net_bridge_port *port);
void br_multicast_del_port(struct net_bridge_port *port);
void br_multicast_enable_port(struct net_bridge_port *port);
void br_multicast_disable_port(struct net_bridge_port *port);
void br_multicast_init(struct net_bridge *br);
void br_multicast_open(struct net_bridge *br);
void br_multicast_stop(struct net_bridge *br);
void br_multicast_dev_del(struct net_bridge *br);
void br_multicast_flood(struct net_bridge_mdb_entry *mdst,
                        struct sk_buff *skb, bool local_rcv, bool local_orig);
int br_multicast_set_router(struct net_bridge *br, unsigned long val);
int br_multicast_set_port_router(struct net_bridge_port *p, unsigned long val);
int br_multicast_toggle(struct net_bridge *br, unsigned long val);
int br_multicast_set_querier(struct net_bridge *br, unsigned long val);
int br_multicast_set_hash_max(struct net_bridge *br, unsigned long val);
int br_multicast_set_igmp_version(struct net_bridge *br, unsigned long val);
#if IS_ENABLED(CONFIG_IPV6)
int br_multicast_set_mld_version(struct net_bridge *br, unsigned long val);
#endif
struct net_bridge_mdb_entry *
br_mdb_ip_get(struct net_bridge_mdb_htable *mdb, struct br_ip *dst);
struct net_bridge_mdb_entry *
br_multicast_new_group(struct net_bridge *br, struct net_bridge_port *port,
                       struct br_ip *group);
void br_multicast_free_pg(struct rcu_head *head);
struct net_bridge_port_group *
br_multicast_new_port_group(struct net_bridge_port *port, struct br_ip *group,
                            struct net_bridge_port_group __rcu *next,
                            unsigned char flags, const unsigned char *src);
void br_mdb_init(void);
void br_mdb_uninit(void);
void br_mdb_notify(struct net_device *dev, struct net_bridge_port *port,
                   struct br_ip *group, int type, u8 flags);
void br_rtr_notify(struct net_device *dev, struct net_bridge_port *port,
                   int type);
void br_multicast_count(struct net_bridge *br, const struct net_bridge_port *p,
                        const struct sk_buff *skb, u8 type, u8 dir);
int br_multicast_init_stats(struct net_bridge *br);
void br_multicast_uninit_stats(struct net_bridge *br);
void br_multicast_get_stats(const struct net_bridge *br,
                            const struct net_bridge_port *p,
                            struct br_mcast_stats *dest);

#define mlock_dereference(X, br) \
        rcu_dereference_protected(X, lockdep_is_held(&br->multicast_lock))

static inline bool br_multicast_is_router(struct net_bridge *br)
{
        return br->multicast_router == 2 ||
               (br->multicast_router == 1 &&
                timer_pending(&br->multicast_router_timer));
}

static inline bool
__br_multicast_querier_exists(struct net_bridge *br,
                                struct bridge_mcast_other_query *querier,
                                const bool is_ipv6)
{
        bool own_querier_enabled;

        if (br->multicast_querier) {
                if (is_ipv6 && !br->has_ipv6_addr)
                        own_querier_enabled = false;
                else
                        own_querier_enabled = true;
        } else {
                own_querier_enabled = false;
        }

        return time_is_before_jiffies(querier->delay_time) &&
               (own_querier_enabled || timer_pending(&querier->timer));
}

static inline bool br_multicast_querier_exists(struct net_bridge *br,
                                               struct ethhdr *eth)
{
        switch (eth->h_proto) {
        case (htons(ETH_P_IP)):
                return __br_multicast_querier_exists(br,
                        &br->ip4_other_query, false);
#if IS_ENABLED(CONFIG_IPV6)
        case (htons(ETH_P_IPV6)):
                return __br_multicast_querier_exists(br,
                        &br->ip6_other_query, true);
#endif
        default:
                return false;
        }
}

static inline int br_multicast_igmp_type(const struct sk_buff *skb)
{
        return BR_INPUT_SKB_CB(skb)->igmp;
}
#else
static inline int br_multicast_rcv(struct net_bridge *br,
                                   struct net_bridge_port *port,
                                   struct sk_buff *skb,
                                   u16 vid)
{
        return 0;
}

static inline struct net_bridge_mdb_entry *br_mdb_get(struct net_bridge *br,
                                                      struct sk_buff *skb, u16 vid)
{
        return NULL;
}

static inline int br_multicast_add_port(struct net_bridge_port *port)
{
        return 0;
}

static inline void br_multicast_del_port(struct net_bridge_port *port)
{
}

static inline void br_multicast_enable_port(struct net_bridge_port *port)
{
}

static inline void br_multicast_disable_port(struct net_bridge_port *port)
{
}

static inline void br_multicast_init(struct net_bridge *br)
{
}

static inline void br_multicast_open(struct net_bridge *br)
{
}

static inline void br_multicast_stop(struct net_bridge *br)
{
}

static inline void br_multicast_dev_del(struct net_bridge *br)
{
}

static inline void br_multicast_flood(struct net_bridge_mdb_entry *mdst,
                                      struct sk_buff *skb,
                                      bool local_rcv, bool local_orig)
{
}

static inline bool br_multicast_is_router(struct net_bridge *br)
{
        return 0;
}

static inline bool br_multicast_querier_exists(struct net_bridge *br,
                                               struct ethhdr *eth)
{
        return false;
}

static inline void br_mdb_init(void)
{
}

static inline void br_mdb_uninit(void)
{
}

static inline void br_multicast_count(struct net_bridge *br,
                                      const struct net_bridge_port *p,
                                      const struct sk_buff *skb,
                                      u8 type, u8 dir)
{
}

static inline int br_multicast_init_stats(struct net_bridge *br)
{
        return 0;
}

static inline void br_multicast_uninit_stats(struct net_bridge *br)
{
}

static inline int br_multicast_igmp_type(const struct sk_buff *skb)
{
        return 0;
}
#endif

/* br_vlan.c */
#ifdef CONFIG_BRIDGE_VLAN_FILTERING
bool br_allowed_ingress(const struct net_bridge *br,
                        struct net_bridge_vlan_group *vg, struct sk_buff *skb,
                        u16 *vid);
bool br_allowed_egress(struct net_bridge_vlan_group *vg,
                       const struct sk_buff *skb);
bool br_should_learn(struct net_bridge_port *p, struct sk_buff *skb, u16 *vid);
struct sk_buff *br_handle_vlan(struct net_bridge *br,
                               const struct net_bridge_port *port,
                               struct net_bridge_vlan_group *vg,
                               struct sk_buff *skb);
int br_vlan_add(struct net_bridge *br, u16 vid, u16 flags,
                bool *changed);
int br_vlan_delete(struct net_bridge *br, u16 vid);
void br_vlan_flush(struct net_bridge *br);
struct net_bridge_vlan *br_vlan_find(struct net_bridge_vlan_group *vg, u16 vid);
void br_recalculate_fwd_mask(struct net_bridge *br);
int __br_vlan_filter_toggle(struct net_bridge *br, unsigned long val);
int br_vlan_filter_toggle(struct net_bridge *br, unsigned long val);
int __br_vlan_set_proto(struct net_bridge *br, __be16 proto);
int br_vlan_set_proto(struct net_bridge *br, unsigned long val);
int br_vlan_set_stats(struct net_bridge *br, unsigned long val);
int br_vlan_init(struct net_bridge *br);
int br_vlan_set_default_pvid(struct net_bridge *br, unsigned long val);
int __br_vlan_set_default_pvid(struct net_bridge *br, u16 pvid);
int nbp_vlan_add(struct net_bridge_port *port, u16 vid, u16 flags,
                 bool *changed);
int nbp_vlan_delete(struct net_bridge_port *port, u16 vid);
void nbp_vlan_flush(struct net_bridge_port *port);
int nbp_vlan_init(struct net_bridge_port *port);
int nbp_get_num_vlan_infos(struct net_bridge_port *p, u32 filter_mask);
void br_vlan_get_stats(const struct net_bridge_vlan *v,
                       struct br_vlan_stats *stats);

static inline struct net_bridge_vlan_group *br_vlan_group(
                                        const struct net_bridge *br)
{
        return rtnl_dereference(br->vlgrp);
}

static inline struct net_bridge_vlan_group *nbp_vlan_group(
                                        const struct net_bridge_port *p)
{
        return rtnl_dereference(p->vlgrp);
}

static inline struct net_bridge_vlan_group *br_vlan_group_rcu(
                                        const struct net_bridge *br)
{
        return rcu_dereference(br->vlgrp);
}

static inline struct net_bridge_vlan_group *nbp_vlan_group_rcu(
                                        const struct net_bridge_port *p)
{
        return rcu_dereference(p->vlgrp);
}

/* Since bridge now depends on 8021Q module, but the time bridge sees the
 * skb, the vlan tag will always be present if the frame was tagged.
 */
static inline int br_vlan_get_tag(const struct sk_buff *skb, u16 *vid)
{
        int err = 0;

        if (skb_vlan_tag_present(skb)) {
                *vid = skb_vlan_tag_get(skb) & VLAN_VID_MASK;
        } else {
                *vid = 0;
                err = -EINVAL;
        }

        return err;
}

static inline u16 br_get_pvid(const struct net_bridge_vlan_group *vg)
{
        if (!vg)
                return 0;

        smp_rmb();
        return vg->pvid;
}

#else
static inline bool br_allowed_ingress(const struct net_bridge *br,
                                      struct net_bridge_vlan_group *vg,
                                      struct sk_buff *skb,
                                      u16 *vid)
{
        return true;
}

static inline bool br_allowed_egress(struct net_bridge_vlan_group *vg,
                                     const struct sk_buff *skb)
{
        return true;
}

static inline bool br_should_learn(struct net_bridge_port *p,
                                   struct sk_buff *skb, u16 *vid)
{
        return true;
}

static inline struct sk_buff *br_handle_vlan(struct net_bridge *br,
                                             const struct net_bridge_port *port,
                                             struct net_bridge_vlan_group *vg,
                                             struct sk_buff *skb)
{
        return skb;
}

static inline int br_vlan_add(struct net_bridge *br, u16 vid, u16 flags,
                              bool *changed)
{
        *changed = false;
        return -EOPNOTSUPP;
}

static inline int br_vlan_delete(struct net_bridge *br, u16 vid)
{
        return -EOPNOTSUPP;
}

static inline void br_vlan_flush(struct net_bridge *br)
{
}

static inline void br_recalculate_fwd_mask(struct net_bridge *br)
{
}

static inline int br_vlan_init(struct net_bridge *br)
{
        return 0;
}

static inline int nbp_vlan_add(struct net_bridge_port *port, u16 vid, u16 flags,
                               bool *changed)
{
        *changed = false;
        return -EOPNOTSUPP;
}

static inline int nbp_vlan_delete(struct net_bridge_port *port, u16 vid)
{
        return -EOPNOTSUPP;
}

static inline void nbp_vlan_flush(struct net_bridge_port *port)
{
}

static inline struct net_bridge_vlan *br_vlan_find(struct net_bridge_vlan_group *vg,
                                                   u16 vid)
{
        return NULL;
}

static inline int nbp_vlan_init(struct net_bridge_port *port)
{
        return 0;
}

static inline u16 br_vlan_get_tag(const struct sk_buff *skb, u16 *tag)
{
        return 0;
}

static inline u16 br_get_pvid(const struct net_bridge_vlan_group *vg)
{
        return 0;
}

static inline int __br_vlan_filter_toggle(struct net_bridge *br,
                                          unsigned long val)
{
        return -EOPNOTSUPP;
}

static inline int nbp_get_num_vlan_infos(struct net_bridge_port *p,
                                         u32 filter_mask)
{
        return 0;
}

static inline struct net_bridge_vlan_group *br_vlan_group(
                                        const struct net_bridge *br)
{
        return NULL;
}

static inline struct net_bridge_vlan_group *nbp_vlan_group(
                                        const struct net_bridge_port *p)
{
        return NULL;
}

static inline struct net_bridge_vlan_group *br_vlan_group_rcu(
                                        const struct net_bridge *br)
{
        return NULL;
}

static inline struct net_bridge_vlan_group *nbp_vlan_group_rcu(
                                        const struct net_bridge_port *p)
{
        return NULL;
}

static inline void br_vlan_get_stats(const struct net_bridge_vlan *v,
                                     struct br_vlan_stats *stats)
{
}
#endif

struct nf_br_ops {
        int (*br_dev_xmit_hook)(struct sk_buff *skb);
};
extern const struct nf_br_ops __rcu *nf_br_ops;

/* br_netfilter.c */
#if IS_ENABLED(CONFIG_BRIDGE_NETFILTER)
int br_nf_core_init(void);
void br_nf_core_fini(void);
void br_netfilter_rtable_init(struct net_bridge *);
#else
static inline int br_nf_core_init(void) { return 0; }
static inline void br_nf_core_fini(void) {}
#define br_netfilter_rtable_init(x)
#endif

/* br_stp.c */
void br_set_state(struct net_bridge_port *p, unsigned int state);
struct net_bridge_port *br_get_port(struct net_bridge *br, u16 port_no);
void br_init_port(struct net_bridge_port *p);
void br_become_designated_port(struct net_bridge_port *p);

void __br_set_forward_delay(struct net_bridge *br, unsigned long t);
int br_set_forward_delay(struct net_bridge *br, unsigned long x);
int br_set_hello_time(struct net_bridge *br, unsigned long x);
int br_set_max_age(struct net_bridge *br, unsigned long x);
int __set_ageing_time(struct net_device *dev, unsigned long t);
int br_set_ageing_time(struct net_bridge *br, clock_t ageing_time);


/* br_stp_if.c */
void br_stp_enable_bridge(struct net_bridge *br);
void br_stp_disable_bridge(struct net_bridge *br);
void br_stp_set_enabled(struct net_bridge *br, unsigned long val);
void br_stp_enable_port(struct net_bridge_port *p);
void br_stp_disable_port(struct net_bridge_port *p);
bool br_stp_recalculate_bridge_id(struct net_bridge *br);
void br_stp_change_bridge_id(struct net_bridge *br, const unsigned char *a);
void br_stp_set_bridge_priority(struct net_bridge *br, u16 newprio);
int br_stp_set_port_priority(struct net_bridge_port *p, unsigned long newprio);
int br_stp_set_path_cost(struct net_bridge_port *p, unsigned long path_cost);
ssize_t br_show_bridge_id(char *buf, const struct bridge_id *id);

/* br_stp_bpdu.c */
struct stp_proto;
void br_stp_rcv(const struct stp_proto *proto, struct sk_buff *skb,
                struct net_device *dev);

/* br_stp_timer.c */
void br_stp_timer_init(struct net_bridge *br);
void br_stp_port_timer_init(struct net_bridge_port *p);
unsigned long br_timer_value(const struct timer_list *timer);

/* br.c */
#if IS_ENABLED(CONFIG_ATM_LANE)
extern int (*br_fdb_test_addr_hook)(struct net_device *dev, unsigned char *addr);
#endif

/* br_netlink.c */
extern struct rtnl_link_ops br_link_ops;
int br_netlink_init(void);
void br_netlink_fini(void);
void br_ifinfo_notify(int event, const struct net_bridge *br,
                      const struct net_bridge_port *port);
int br_setlink(struct net_device *dev, struct nlmsghdr *nlmsg, u16 flags);
int br_dellink(struct net_device *dev, struct nlmsghdr *nlmsg, u16 flags);
int br_getlink(struct sk_buff *skb, u32 pid, u32 seq, struct net_device *dev,
               u32 filter_mask, int nlflags);

#ifdef CONFIG_SYSFS
/* br_sysfs_if.c */
extern const struct sysfs_ops brport_sysfs_ops;
int br_sysfs_addif(struct net_bridge_port *p);
int br_sysfs_renameif(struct net_bridge_port *p);

/* br_sysfs_br.c */
int br_sysfs_addbr(struct net_device *dev);
void br_sysfs_delbr(struct net_device *dev);

#else

static inline int br_sysfs_addif(struct net_bridge_port *p) { return 0; }
static inline int br_sysfs_renameif(struct net_bridge_port *p) { return 0; }
static inline int br_sysfs_addbr(struct net_device *dev) { return 0; }
static inline void br_sysfs_delbr(struct net_device *dev) { return; }
#endif /* CONFIG_SYSFS */

/* br_switchdev.c */
#ifdef CONFIG_NET_SWITCHDEV
int nbp_switchdev_mark_set(struct net_bridge_port *p);
void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
                              struct sk_buff *skb);
bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
                                  const struct sk_buff *skb);
int br_switchdev_set_port_flag(struct net_bridge_port *p,
                               unsigned long flags,
                               unsigned long mask);
void br_switchdev_fdb_notify(const struct net_bridge_fdb_entry *fdb,
                             int type);

static inline void br_switchdev_frame_unmark(struct sk_buff *skb)
{
        skb->offload_fwd_mark = 0;
}
#else
static inline int nbp_switchdev_mark_set(struct net_bridge_port *p)
{
        return 0;
}

static inline void nbp_switchdev_frame_mark(const struct net_bridge_port *p,
                                            struct sk_buff *skb)
{
}

static inline bool nbp_switchdev_allowed_egress(const struct net_bridge_port *p,
                                                const struct sk_buff *skb)
{
        return true;
}

static inline int br_switchdev_set_port_flag(struct net_bridge_port *p,
                                             unsigned long flags,
                                             unsigned long mask)
{
        return 0;
}

static inline void
br_switchdev_fdb_notify(const struct net_bridge_fdb_entry *fdb, int type)
{
}

static inline void br_switchdev_frame_unmark(struct sk_buff *skb)
{
}
#endif /* CONFIG_NET_SWITCHDEV */

/* br_arp_nd_proxy.c */
void br_recalculate_neigh_suppress_enabled(struct net_bridge *br);
void br_do_proxy_suppress_arp(struct sk_buff *skb, struct net_bridge *br,
                              u16 vid, struct net_bridge_port *p);
void br_do_suppress_nd(struct sk_buff *skb, struct net_bridge *br,
                       u16 vid, struct net_bridge_port *p, struct nd_msg *msg);
struct nd_msg *br_is_nd_neigh_msg(struct sk_buff *skb, struct nd_msg *m);
#endif