/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _LINUX_INETDEVICE_H
#define _LINUX_INETDEVICE_H

#ifdef __KERNEL__

#include <linux/bitmap.h>
#include <linux/if.h>
#include <linux/ip.h>
#include <linux/netdevice.h>
#include <linux/rcupdate.h>
#include <linux/timer.h>
#include <linux/sysctl.h>
#include <linux/rtnetlink.h>
#include <linux/refcount.h>

struct ipv4_devconf {
        void    *sysctl;
        int     data[IPV4_DEVCONF_MAX];
        DECLARE_BITMAP(state, IPV4_DEVCONF_MAX);
};

#define MC_HASH_SZ_LOG 9

struct in_device {
        struct net_device       *dev;
        netdevice_tracker       dev_tracker;

        refcount_t              refcnt;
        int                     dead;
        struct in_ifaddr        __rcu *ifa_list;/* IP ifaddr chain              */

        struct ip_mc_list __rcu *mc_list;       /* IP multicast filter chain    */
        struct ip_mc_list __rcu * __rcu *mc_hash;

        int                     mc_count;       /* Number of installed mcasts   */
        spinlock_t              mc_tomb_lock;
        struct ip_mc_list       *mc_tomb;
        unsigned long           mr_v1_seen;
        unsigned long           mr_v2_seen;
        unsigned long           mr_qi;          /* Query Interval */
        unsigned long           mr_qri;         /* Query Response Interval */
        unsigned char           mr_qrv;         /* Query Robustness Variable */
        unsigned char           mr_gq_running;
        u32                     mr_maxdelay;
        u32                     mr_ifc_count;
        struct timer_list       mr_gq_timer;    /* general query timer */
        struct timer_list       mr_ifc_timer;   /* interface change timer */

        struct neigh_parms      *arp_parms;
        struct ipv4_devconf     cnf;
        struct rcu_head         rcu_head;
};

#define IPV4_DEVCONF(cnf, attr) ((cnf).data[IPV4_DEVCONF_ ## attr - 1])
#define IPV4_DEVCONF_RO(cnf, attr) READ_ONCE(IPV4_DEVCONF(cnf, attr))
#define IPV4_DEVCONF_ALL(net, attr) \
        IPV4_DEVCONF((*(net)->ipv4.devconf_all), attr)
#define IPV4_DEVCONF_ALL_RO(net, attr) READ_ONCE(IPV4_DEVCONF_ALL(net, attr))

static inline int ipv4_devconf_get(const struct in_device *in_dev, int index)
{
        index--;
        return READ_ONCE(in_dev->cnf.data[index]);
}

static inline void ipv4_devconf_set(struct in_device *in_dev, int index,
                                    int val)
{
        index--;
        set_bit(index, in_dev->cnf.state);
        WRITE_ONCE(in_dev->cnf.data[index], val);
}

static inline void ipv4_devconf_setall(struct in_device *in_dev)
{
        bitmap_fill(in_dev->cnf.state, IPV4_DEVCONF_MAX);
}

#define IN_DEV_CONF_GET(in_dev, attr) \
        ipv4_devconf_get((in_dev), IPV4_DEVCONF_ ## attr)
#define IN_DEV_CONF_SET(in_dev, attr, val) \
        ipv4_devconf_set((in_dev), IPV4_DEVCONF_ ## attr, (val))

#define IN_DEV_ANDCONF(in_dev, attr) \
        (IPV4_DEVCONF_ALL_RO(dev_net(in_dev->dev), attr) && \
         IN_DEV_CONF_GET((in_dev), attr))

#define IN_DEV_NET_ORCONF(in_dev, net, attr) \
        (IPV4_DEVCONF_ALL_RO(net, attr) || \
         IN_DEV_CONF_GET((in_dev), attr))

#define IN_DEV_ORCONF(in_dev, attr) \
        IN_DEV_NET_ORCONF(in_dev, dev_net(in_dev->dev), attr)

#define IN_DEV_MAXCONF(in_dev, attr) \
        (max(IPV4_DEVCONF_ALL_RO(dev_net(in_dev->dev), attr), \
             IN_DEV_CONF_GET((in_dev), attr)))

#define IN_DEV_FORWARD(in_dev)          IN_DEV_CONF_GET((in_dev), FORWARDING)
#define IN_DEV_MFORWARD(in_dev)         IN_DEV_ANDCONF((in_dev), MC_FORWARDING)
#define IN_DEV_BFORWARD(in_dev)         IN_DEV_ANDCONF((in_dev), BC_FORWARDING)
#define IN_DEV_RPFILTER(in_dev)         IN_DEV_MAXCONF((in_dev), RP_FILTER)
#define IN_DEV_SRC_VMARK(in_dev)        IN_DEV_ORCONF((in_dev), SRC_VMARK)
#define IN_DEV_SOURCE_ROUTE(in_dev)     IN_DEV_ANDCONF((in_dev), \
                                                       ACCEPT_SOURCE_ROUTE)
#define IN_DEV_ACCEPT_LOCAL(in_dev)     IN_DEV_ORCONF((in_dev), ACCEPT_LOCAL)
#define IN_DEV_BOOTP_RELAY(in_dev)      IN_DEV_ANDCONF((in_dev), BOOTP_RELAY)

#define IN_DEV_LOG_MARTIANS(in_dev)     IN_DEV_ORCONF((in_dev), LOG_MARTIANS)
#define IN_DEV_PROXY_ARP(in_dev)        IN_DEV_ORCONF((in_dev), PROXY_ARP)
#define IN_DEV_PROXY_ARP_PVLAN(in_dev)  IN_DEV_ORCONF((in_dev), PROXY_ARP_PVLAN)
#define IN_DEV_SHARED_MEDIA(in_dev)     IN_DEV_ORCONF((in_dev), SHARED_MEDIA)
#define IN_DEV_TX_REDIRECTS(in_dev)     IN_DEV_ORCONF((in_dev), SEND_REDIRECTS)
#define IN_DEV_SEC_REDIRECTS(in_dev)    IN_DEV_ORCONF((in_dev), \
                                                      SECURE_REDIRECTS)
#define IN_DEV_IDTAG(in_dev)            IN_DEV_CONF_GET(in_dev, TAG)
#define IN_DEV_MEDIUM_ID(in_dev)        IN_DEV_CONF_GET(in_dev, MEDIUM_ID)
#define IN_DEV_PROMOTE_SECONDARIES(in_dev) \
                                        IN_DEV_ORCONF((in_dev), \
                                                      PROMOTE_SECONDARIES)
#define IN_DEV_ROUTE_LOCALNET(in_dev)   IN_DEV_ORCONF(in_dev, ROUTE_LOCALNET)
#define IN_DEV_NET_ROUTE_LOCALNET(in_dev, net)  \
        IN_DEV_NET_ORCONF(in_dev, net, ROUTE_LOCALNET)

#define IN_DEV_RX_REDIRECTS(in_dev) \
        ((IN_DEV_FORWARD(in_dev) && \
          IN_DEV_ANDCONF((in_dev), ACCEPT_REDIRECTS)) \
         || (!IN_DEV_FORWARD(in_dev) && \
          IN_DEV_ORCONF((in_dev), ACCEPT_REDIRECTS)))

#define IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev) \
        IN_DEV_ORCONF((in_dev), IGNORE_ROUTES_WITH_LINKDOWN)

#define IN_DEV_ARPFILTER(in_dev)        IN_DEV_ORCONF((in_dev), ARPFILTER)
#define IN_DEV_ARP_ACCEPT(in_dev)       IN_DEV_MAXCONF((in_dev), ARP_ACCEPT)
#define IN_DEV_ARP_ANNOUNCE(in_dev)     IN_DEV_MAXCONF((in_dev), ARP_ANNOUNCE)
#define IN_DEV_ARP_IGNORE(in_dev)       IN_DEV_MAXCONF((in_dev), ARP_IGNORE)
#define IN_DEV_ARP_NOTIFY(in_dev)       IN_DEV_MAXCONF((in_dev), ARP_NOTIFY)
#define IN_DEV_ARP_EVICT_NOCARRIER(in_dev) IN_DEV_ANDCONF((in_dev), \
                                                          ARP_EVICT_NOCARRIER)

struct in_ifaddr {
        struct hlist_node       addr_lst;
        struct in_ifaddr        __rcu *ifa_next;
        struct in_device        *ifa_dev;
        struct rcu_head         rcu_head;
        __be32                  ifa_local;
        __be32                  ifa_address;
        __be32                  ifa_mask;
        __u32                   ifa_rt_priority;
        __be32                  ifa_broadcast;
        unsigned char           ifa_scope;
        unsigned char           ifa_prefixlen;
        unsigned char           ifa_proto;
        __u32                   ifa_flags;
        char                    ifa_label[IFNAMSIZ];

        /* In seconds, relative to tstamp. Expiry is at tstamp + HZ * lft. */
        __u32                   ifa_valid_lft;
        __u32                   ifa_preferred_lft;
        unsigned long           ifa_cstamp; /* created timestamp */
        unsigned long           ifa_tstamp; /* updated timestamp */
};

struct in_validator_info {
        __be32                  ivi_addr;
        struct in_device        *ivi_dev;
        struct netlink_ext_ack  *extack;
};

int register_inetaddr_notifier(struct notifier_block *nb);
int unregister_inetaddr_notifier(struct notifier_block *nb);
int register_inetaddr_validator_notifier(struct notifier_block *nb);
int unregister_inetaddr_validator_notifier(struct notifier_block *nb);

void inet_netconf_notify_devconf(struct net *net, int event, int type,
                                 int ifindex, struct ipv4_devconf *devconf);

struct net_device *__ip_dev_find(struct net *net, __be32 addr, bool devref);
static inline struct net_device *ip_dev_find(struct net *net, __be32 addr)
{
        return __ip_dev_find(net, addr, true);
}

int inet_addr_onlink(struct in_device *in_dev, __be32 a, __be32 b);
int devinet_ioctl(struct net *net, unsigned int cmd, struct ifreq *);
#ifdef CONFIG_INET
int inet_gifconf(struct net_device *dev, char __user *buf, int len, int size);
#else
static inline int inet_gifconf(struct net_device *dev, char __user *buf,
                               int len, int size)
{
        return 0;
}
#endif
void devinet_init(void);
struct in_device *inetdev_by_index(struct net *, int);
__be32 inet_select_addr(const struct net_device *dev, __be32 dst, int scope);
__be32 inet_confirm_addr(struct net *net, struct in_device *in_dev, __be32 dst,
                         __be32 local, int scope);
struct in_ifaddr *inet_ifa_byprefix(struct in_device *in_dev, __be32 prefix,
                                    __be32 mask);
struct in_ifaddr *inet_lookup_ifaddr_rcu(struct net *net, __be32 addr);
static inline bool inet_ifa_match(__be32 addr, const struct in_ifaddr *ifa)
{
        return !((addr^ifa->ifa_address)&ifa->ifa_mask);
}

/*
 *      Check if a mask is acceptable.
 */
 
static __inline__ bool bad_mask(__be32 mask, __be32 addr)
{
        __u32 hmask;
        if (addr & (mask = ~mask))
                return true;
        hmask = ntohl(mask);
        if (hmask & (hmask+1))
                return true;
        return false;
}

#define in_dev_for_each_ifa_rtnl(ifa, in_dev)                   \
        for (ifa = rtnl_dereference((in_dev)->ifa_list); ifa;   \
             ifa = rtnl_dereference(ifa->ifa_next))

#define in_dev_for_each_ifa_rtnl_net(net, ifa, in_dev)                  \
        for (ifa = rtnl_net_dereference(net, (in_dev)->ifa_list); ifa;  \
             ifa = rtnl_net_dereference(net, ifa->ifa_next))

#define in_dev_for_each_ifa_rcu(ifa, in_dev)                    \
        for (ifa = rcu_dereference((in_dev)->ifa_list); ifa;    \
             ifa = rcu_dereference(ifa->ifa_next))

static inline struct in_device *__in_dev_get_rcu(const struct net_device *dev)
{
        return rcu_dereference(dev->ip_ptr);
}

static inline struct in_device *in_dev_get(const struct net_device *dev)
{
        struct in_device *in_dev;

        rcu_read_lock();
        in_dev = __in_dev_get_rcu(dev);
        if (in_dev)
                refcount_inc(&in_dev->refcnt);
        rcu_read_unlock();
        return in_dev;
}

static inline struct in_device *__in_dev_get_rtnl(const struct net_device *dev)
{
        return rtnl_dereference(dev->ip_ptr);
}

static inline struct in_device *__in_dev_get_rtnl_net(const struct net_device *dev)
{
        return rtnl_net_dereference(dev_net(dev), dev->ip_ptr);
}

/* called with rcu_read_lock or rtnl held */
static inline bool ip_ignore_linkdown(const struct net_device *dev)
{
        struct in_device *in_dev;
        bool rc = false;

        in_dev = rcu_dereference_rtnl(dev->ip_ptr);
        if (in_dev &&
            IN_DEV_IGNORE_ROUTES_WITH_LINKDOWN(in_dev))
                rc = true;

        return rc;
}

static inline struct neigh_parms *__in_dev_arp_parms_get_rcu(const struct net_device *dev)
{
        struct in_device *in_dev = __in_dev_get_rcu(dev);

        return in_dev ? in_dev->arp_parms : NULL;
}

void in_dev_finish_destroy(struct in_device *idev);

static inline void in_dev_put(struct in_device *idev)
{
        if (refcount_dec_and_test(&idev->refcnt))
                in_dev_finish_destroy(idev);
}

#define __in_dev_put(idev)  refcount_dec(&(idev)->refcnt)
#define in_dev_hold(idev)   refcount_inc(&(idev)->refcnt)

#endif /* __KERNEL__ */

static __inline__ __be32 inet_make_mask(int logmask)
{
        if (logmask)
                return htonl(~((1U<<(32-logmask))-1));
        return 0;
}

static __inline__ int inet_mask_len(__be32 mask)
{
        __u32 hmask = ntohl(mask);
        if (!hmask)
                return 0;
        return 32 - ffz(~hmask);
}


#endif /* _LINUX_INETDEVICE_H */