#ifndef __LINUX_MROUTE_BASE_H
#define __LINUX_MROUTE_BASE_H

#include <linux/netdevice.h>
#include <linux/rhashtable-types.h>
#include <linux/spinlock.h>
#include <net/net_namespace.h>
#include <net/sock.h>
#include <net/fib_notifier.h>
#include <net/ip_fib.h>

/**
 * struct vif_device - interface representor for multicast routing
 * @dev: network device being used
 * @dev_tracker: refcount tracker for @dev reference
 * @bytes_in: statistic; bytes ingressing
 * @bytes_out: statistic; bytes egresing
 * @pkt_in: statistic; packets ingressing
 * @pkt_out: statistic; packets egressing
 * @rate_limit: Traffic shaping (NI)
 * @threshold: TTL threshold
 * @flags: Control flags
 * @link: Physical interface index
 * @dev_parent_id: device parent id
 * @local: Local address
 * @remote: Remote address for tunnels
 */
struct vif_device {
        struct net_device __rcu *dev;
        netdevice_tracker dev_tracker;
        unsigned long bytes_in, bytes_out;
        unsigned long pkt_in, pkt_out;
        unsigned long rate_limit;
        unsigned char threshold;
        unsigned short flags;
        int link;

        /* Currently only used by ipmr */
        struct netdev_phys_item_id dev_parent_id;
        __be32 local, remote;
};

struct vif_entry_notifier_info {
        struct fib_notifier_info info;
        struct net_device *dev;
        unsigned short vif_index;
        unsigned short vif_flags;
        u32 tb_id;
};

static inline int mr_call_vif_notifier(struct notifier_block *nb,
                                       unsigned short family,
                                       enum fib_event_type event_type,
                                       struct vif_device *vif,
                                       struct net_device *vif_dev,
                                       unsigned short vif_index, u32 tb_id,
                                       struct netlink_ext_ack *extack)
{
        struct vif_entry_notifier_info info = {
                .info = {
                        .family = family,
                        .extack = extack,
                },
                .dev = vif_dev,
                .vif_index = vif_index,
                .vif_flags = vif->flags,
                .tb_id = tb_id,
        };

        return call_fib_notifier(nb, event_type, &info.info);
}

static inline int mr_call_vif_notifiers(struct net *net,
                                        unsigned short family,
                                        enum fib_event_type event_type,
                                        struct vif_device *vif,
                                        struct net_device *vif_dev,
                                        unsigned short vif_index, u32 tb_id,
                                        unsigned int *ipmr_seq)
{
        struct vif_entry_notifier_info info = {
                .info = {
                        .family = family,
                },
                .dev = vif_dev,
                .vif_index = vif_index,
                .vif_flags = vif->flags,
                .tb_id = tb_id,
        };

        ASSERT_RTNL();
        (*ipmr_seq)++;
        return call_fib_notifiers(net, event_type, &info.info);
}

#ifndef MAXVIFS
/* This one is nasty; value is defined in uapi using different symbols for
 * mroute and morute6 but both map into same 32.
 */
#define MAXVIFS 32
#endif

/* Note: This helper is deprecated. */
#define VIF_EXISTS(_mrt, _idx) (!!rcu_access_pointer((_mrt)->vif_table[_idx].dev))

/* mfc_flags:
 * MFC_STATIC - the entry was added statically (not by a routing daemon)
 * MFC_OFFLOAD - the entry was offloaded to the hardware
 */
enum {
        MFC_STATIC = BIT(0),
        MFC_OFFLOAD = BIT(1),
};

/**
 * struct mr_mfc - common multicast routing entries
 * @mnode: rhashtable list
 * @mfc_parent: source interface (iif)
 * @mfc_flags: entry flags
 * @expires: unresolved entry expire time
 * @unresolved: unresolved cached skbs
 * @last_assert: time of last assert
 * @minvif: minimum VIF id
 * @maxvif: maximum VIF id
 * @bytes: bytes that have passed for this entry
 * @pkt: packets that have passed for this entry
 * @wrong_if: number of wrong source interface hits
 * @lastuse: time of last use of the group (traffic or update)
 * @ttls: OIF TTL threshold array
 * @refcount: reference count for this entry
 * @list: global entry list
 * @rcu: used for entry destruction
 * @free: Operation used for freeing an entry under RCU
 */
struct mr_mfc {
        struct rhlist_head mnode;
        unsigned short mfc_parent;
        int mfc_flags;

        union {
                struct {
                        unsigned long expires;
                        struct sk_buff_head unresolved;
                } unres;
                struct {
                        unsigned long last_assert;
                        int minvif;
                        int maxvif;
                        atomic_long_t bytes;
                        atomic_long_t pkt;
                        atomic_long_t wrong_if;
                        unsigned long lastuse;
                        unsigned char ttls[MAXVIFS];
                        refcount_t refcount;
                } res;
        } mfc_un;
        struct list_head list;
        struct rcu_head rcu;
        void (*free)(struct rcu_head *head);
};

static inline void mr_cache_put(struct mr_mfc *c)
{
        if (refcount_dec_and_test(&c->mfc_un.res.refcount))
                call_rcu(&c->rcu, c->free);
}

static inline void mr_cache_hold(struct mr_mfc *c)
{
        refcount_inc(&c->mfc_un.res.refcount);
}

struct mfc_entry_notifier_info {
        struct fib_notifier_info info;
        struct mr_mfc *mfc;
        u32 tb_id;
};

static inline int mr_call_mfc_notifier(struct notifier_block *nb,
                                       unsigned short family,
                                       enum fib_event_type event_type,
                                       struct mr_mfc *mfc, u32 tb_id,
                                       struct netlink_ext_ack *extack)
{
        struct mfc_entry_notifier_info info = {
                .info = {
                        .family = family,
                        .extack = extack,
                },
                .mfc = mfc,
                .tb_id = tb_id
        };

        return call_fib_notifier(nb, event_type, &info.info);
}

static inline int mr_call_mfc_notifiers(struct net *net,
                                        unsigned short family,
                                        enum fib_event_type event_type,
                                        struct mr_mfc *mfc, u32 tb_id,
                                        unsigned int *ipmr_seq)
{
        struct mfc_entry_notifier_info info = {
                .info = {
                        .family = family,
                },
                .mfc = mfc,
                .tb_id = tb_id
        };

        ASSERT_RTNL();
        (*ipmr_seq)++;
        return call_fib_notifiers(net, event_type, &info.info);
}

struct mr_table;

/**
 * struct mr_table_ops - callbacks and info for protocol-specific ops
 * @rht_params: parameters for accessing the MFC hash
 * @cmparg_any: a hash key to be used for matching on (*,*) routes
 */
struct mr_table_ops {
        const struct rhashtable_params *rht_params;
        void *cmparg_any;
};

/**
 * struct mr_table - a multicast routing table
 * @list: entry within a list of multicast routing tables
 * @net: net where this table belongs
 * @ops: protocol specific operations
 * @id: identifier of the table
 * @mroute_sk: socket associated with the table
 * @ipmr_expire_timer: timer for handling unresolved routes
 * @mfc_unres_queue: list of unresolved MFC entries
 * @vif_table: array containing all possible vifs
 * @mfc_hash: Hash table of all resolved routes for easy lookup
 * @mfc_cache_list: list of resovled routes for possible traversal
 * @maxvif: Identifier of highest value vif currently in use
 * @cache_resolve_queue_len: current size of unresolved queue
 * @mroute_do_assert: Whether to inform userspace on wrong ingress
 * @mroute_do_pim: Whether to receive IGMP PIMv1
 * @mroute_reg_vif_num: PIM-device vif index
 */
struct mr_table {
        struct list_head        list;
        possible_net_t          net;
        struct mr_table_ops     ops;
        u32                     id;
        struct sock __rcu       *mroute_sk;
        struct timer_list       ipmr_expire_timer;
        struct list_head        mfc_unres_queue;
        struct vif_device       vif_table[MAXVIFS];
        struct rhltable         mfc_hash;
        struct list_head        mfc_cache_list;
        int                     maxvif;
        atomic_t                cache_resolve_queue_len;
        bool                    mroute_do_assert;
        bool                    mroute_do_pim;
        bool                    mroute_do_wrvifwhole;
        int                     mroute_reg_vif_num;
};

static inline bool mr_can_free_table(struct net *net)
{
        return !check_net(net) || !net_initialized(net);
}

#ifdef CONFIG_IP_MROUTE_COMMON
void vif_device_init(struct vif_device *v,
                     struct net_device *dev,
                     unsigned long rate_limit,
                     unsigned char threshold,
                     unsigned short flags,
                     unsigned short get_iflink_mask);

struct mr_table *
mr_table_alloc(struct net *net, u32 id,
               struct mr_table_ops *ops,
               void (*expire_func)(struct timer_list *t),
               void (*table_set)(struct mr_table *mrt,
                                 struct net *net));

/* These actually return 'struct mr_mfc *', but to avoid need for explicit
 * castings they simply return void.
 */
void *mr_mfc_find_parent(struct mr_table *mrt,
                         void *hasharg, int parent);
void *mr_mfc_find_any_parent(struct mr_table *mrt, int vifi);
void *mr_mfc_find_any(struct mr_table *mrt, int vifi, void *hasharg);

int mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
                   struct mr_mfc *c, struct rtmsg *rtm);
int mr_table_dump(struct mr_table *mrt, struct sk_buff *skb,
                  struct netlink_callback *cb,
                  int (*fill)(struct mr_table *mrt, struct sk_buff *skb,
                              u32 portid, u32 seq, struct mr_mfc *c,
                              int cmd, int flags),
                  spinlock_t *lock, struct fib_dump_filter *filter);
int mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb,
                     struct mr_table *(*iter)(struct net *net,
                                              struct mr_table *mrt),
                     int (*fill)(struct mr_table *mrt,
                                 struct sk_buff *skb,
                                 u32 portid, u32 seq, struct mr_mfc *c,
                                 int cmd, int flags),
                     spinlock_t *lock, struct fib_dump_filter *filter);

int mr_dump(struct net *net, struct notifier_block *nb, unsigned short family,
            int (*rules_dump)(struct net *net,
                              struct notifier_block *nb,
                              struct netlink_ext_ack *extack),
            struct mr_table *(*mr_iter)(struct net *net,
                                        struct mr_table *mrt),
            struct netlink_ext_ack *extack);
#else
static inline void vif_device_init(struct vif_device *v,
                                   struct net_device *dev,
                                   unsigned long rate_limit,
                                   unsigned char threshold,
                                   unsigned short flags,
                                   unsigned short get_iflink_mask)
{
}

static inline void *mr_mfc_find_parent(struct mr_table *mrt,
                                       void *hasharg, int parent)
{
        return NULL;
}

static inline void *mr_mfc_find_any_parent(struct mr_table *mrt,
                                           int vifi)
{
        return NULL;
}

static inline struct mr_mfc *mr_mfc_find_any(struct mr_table *mrt,
                                             int vifi, void *hasharg)
{
        return NULL;
}

static inline int mr_fill_mroute(struct mr_table *mrt, struct sk_buff *skb,
                                 struct mr_mfc *c, struct rtmsg *rtm)
{
        return -EINVAL;
}

static inline int
mr_rtm_dumproute(struct sk_buff *skb, struct netlink_callback *cb,
                 struct mr_table *(*iter)(struct net *net,
                                          struct mr_table *mrt),
                 int (*fill)(struct mr_table *mrt,
                             struct sk_buff *skb,
                             u32 portid, u32 seq, struct mr_mfc *c,
                             int cmd, int flags),
                 spinlock_t *lock, struct fib_dump_filter *filter)
{
        return -EINVAL;
}

static inline int mr_dump(struct net *net, struct notifier_block *nb,
                          unsigned short family,
                          int (*rules_dump)(struct net *net,
                                            struct notifier_block *nb,
                                            struct netlink_ext_ack *extack),
                          struct mr_table *(*mr_iter)(struct net *net,
                                                      struct mr_table *mrt),
                          struct netlink_ext_ack *extack)
{
        return -EINVAL;
}
#endif

static inline void *mr_mfc_find(struct mr_table *mrt, void *hasharg)
{
        return mr_mfc_find_parent(mrt, hasharg, -1);
}

#ifdef CONFIG_PROC_FS
struct mr_vif_iter {
        struct seq_net_private p;
        struct mr_table *mrt;
        int ct;
};

struct mr_mfc_iter {
        struct seq_net_private p;
        struct mr_table *mrt;
        struct list_head *cache;

        /* Lock protecting the mr_table's unresolved queue */
        spinlock_t *lock;
};

#ifdef CONFIG_IP_MROUTE_COMMON
void *mr_vif_seq_idx(struct net *net, struct mr_vif_iter *iter, loff_t pos);
void *mr_vif_seq_next(struct seq_file *seq, void *v, loff_t *pos);

static inline void *mr_vif_seq_start(struct seq_file *seq, loff_t *pos)
{
        return *pos ? mr_vif_seq_idx(seq_file_net(seq),
                                     seq->private, *pos - 1)
                    : SEQ_START_TOKEN;
}

/* These actually return 'struct mr_mfc *', but to avoid need for explicit
 * castings they simply return void.
 */
void *mr_mfc_seq_idx(struct net *net,
                     struct mr_mfc_iter *it, loff_t pos);
void *mr_mfc_seq_next(struct seq_file *seq, void *v,
                      loff_t *pos);

static inline void *mr_mfc_seq_start(struct seq_file *seq, loff_t *pos,
                                     struct mr_table *mrt, spinlock_t *lock)
{
        struct mr_mfc_iter *it = seq->private;

        it->mrt = mrt;
        it->cache = NULL;
        it->lock = lock;

        return *pos ? mr_mfc_seq_idx(seq_file_net(seq),
                                     seq->private, *pos - 1)
                    : SEQ_START_TOKEN;
}

static inline void mr_mfc_seq_stop(struct seq_file *seq, void *v)
{
        struct mr_mfc_iter *it = seq->private;
        struct mr_table *mrt = it->mrt;

        if (it->cache == &mrt->mfc_unres_queue)
                spin_unlock_bh(it->lock);
        else if (it->cache == &mrt->mfc_cache_list)
                rcu_read_unlock();
}
#else
static inline void *mr_vif_seq_idx(struct net *net, struct mr_vif_iter *iter,
                                   loff_t pos)
{
        return NULL;
}

static inline void *mr_vif_seq_next(struct seq_file *seq,
                                    void *v, loff_t *pos)
{
        return NULL;
}

static inline void *mr_vif_seq_start(struct seq_file *seq, loff_t *pos)
{
        return NULL;
}

static inline void *mr_mfc_seq_idx(struct net *net,
                                   struct mr_mfc_iter *it, loff_t pos)
{
        return NULL;
}

static inline void *mr_mfc_seq_next(struct seq_file *seq, void *v,
                                    loff_t *pos)
{
        return NULL;
}

static inline void *mr_mfc_seq_start(struct seq_file *seq, loff_t *pos,
                                     struct mr_table *mrt, spinlock_t *lock)
{
        return NULL;
}

static inline void mr_mfc_seq_stop(struct seq_file *seq, void *v)
{
}
#endif
#endif
#endif