/* SPDX-License-Identifier: GPL-2.0 */
/*
 *
 *      Generic internet FLOW.
 *
 */

#ifndef _NET_FLOW_H
#define _NET_FLOW_H

#include <linux/in6.h>
#include <linux/atomic.h>
#include <linux/container_of.h>
#include <linux/uidgid.h>
#include <net/inet_dscp.h>

struct flow_keys;

/*
 * ifindex generation is per-net namespace, and loopback is
 * always the 1st device in ns (see net_dev_init), thus any
 * loopback device should get ifindex 1
 */

#define LOOPBACK_IFINDEX        1

struct flowi_tunnel {
        __be64                  tun_id;
};

struct flowi_common {
        int     flowic_oif;
        int     flowic_iif;
        int     flowic_l3mdev;
        __u32   flowic_mark;
        dscp_t  flowic_dscp;
        __u8    flowic_scope;
        __u8    flowic_proto;
        __u8    flowic_flags;
#define FLOWI_FLAG_ANYSRC               0x01
#define FLOWI_FLAG_KNOWN_NH             0x02
#define FLOWI_FLAG_L3MDEV_OIF           0x04
#define FLOWI_FLAG_ANY_SPORT            0x08
        __u32   flowic_secid;
        kuid_t  flowic_uid;
        __u32           flowic_multipath_hash;
        struct flowi_tunnel flowic_tun_key;
};

union flowi_uli {
        struct {
                __be16  dport;
                __be16  sport;
        } ports;

        struct {
                __u8    type;
                __u8    code;
        } icmpt;

        __be32          gre_key;

        struct {
                __u8    type;
        } mht;
};

struct flowi4 {
        struct flowi_common     __fl_common;
#define flowi4_oif              __fl_common.flowic_oif
#define flowi4_iif              __fl_common.flowic_iif
#define flowi4_l3mdev           __fl_common.flowic_l3mdev
#define flowi4_mark             __fl_common.flowic_mark
#define flowi4_dscp             __fl_common.flowic_dscp
#define flowi4_scope            __fl_common.flowic_scope
#define flowi4_proto            __fl_common.flowic_proto
#define flowi4_flags            __fl_common.flowic_flags
#define flowi4_secid            __fl_common.flowic_secid
#define flowi4_tun_key          __fl_common.flowic_tun_key
#define flowi4_uid              __fl_common.flowic_uid
#define flowi4_multipath_hash   __fl_common.flowic_multipath_hash

        /* (saddr,daddr) must be grouped, same order as in IP header */
        __be32                  saddr;
        __be32                  daddr;

        union flowi_uli         uli;
#define fl4_sport               uli.ports.sport
#define fl4_dport               uli.ports.dport
#define fl4_icmp_type           uli.icmpt.type
#define fl4_icmp_code           uli.icmpt.code
#define fl4_mh_type             uli.mht.type
#define fl4_gre_key             uli.gre_key
} __attribute__((__aligned__(BITS_PER_LONG/8)));

static inline void flowi4_init_output(struct flowi4 *fl4, int oif,
                                      __u32 mark, __u8 tos, __u8 scope,
                                      __u8 proto, __u8 flags,
                                      __be32 daddr, __be32 saddr,
                                      __be16 dport, __be16 sport,
                                      kuid_t uid)
{
        fl4->flowi4_oif = oif;
        fl4->flowi4_iif = LOOPBACK_IFINDEX;
        fl4->flowi4_l3mdev = 0;
        fl4->flowi4_mark = mark;
        fl4->flowi4_dscp = inet_dsfield_to_dscp(tos);
        fl4->flowi4_scope = scope;
        fl4->flowi4_proto = proto;
        fl4->flowi4_flags = flags;
        fl4->flowi4_secid = 0;
        fl4->flowi4_tun_key.tun_id = 0;
        fl4->flowi4_uid = uid;
        fl4->daddr = daddr;
        fl4->saddr = saddr;
        fl4->fl4_dport = dport;
        fl4->fl4_sport = sport;
        fl4->flowi4_multipath_hash = 0;
}

/* Reset some input parameters after previous lookup */
static inline void flowi4_update_output(struct flowi4 *fl4, int oif,
                                        __be32 daddr, __be32 saddr)
{
        fl4->flowi4_oif = oif;
        fl4->daddr = daddr;
        fl4->saddr = saddr;
}


struct flowi6 {
        struct flowi_common     __fl_common;
#define flowi6_oif              __fl_common.flowic_oif
#define flowi6_iif              __fl_common.flowic_iif
#define flowi6_l3mdev           __fl_common.flowic_l3mdev
#define flowi6_mark             __fl_common.flowic_mark
#define flowi6_scope            __fl_common.flowic_scope
#define flowi6_proto            __fl_common.flowic_proto
#define flowi6_flags            __fl_common.flowic_flags
#define flowi6_secid            __fl_common.flowic_secid
#define flowi6_tun_key          __fl_common.flowic_tun_key
#define flowi6_uid              __fl_common.flowic_uid
        struct in6_addr         daddr;
        struct in6_addr         saddr;
        /* Note: flowi6_dscp is encoded in flowlabel, too. */
        __be32                  flowlabel;
        union flowi_uli         uli;
#define fl6_sport               uli.ports.sport
#define fl6_dport               uli.ports.dport
#define fl6_icmp_type           uli.icmpt.type
#define fl6_icmp_code           uli.icmpt.code
#define fl6_mh_type             uli.mht.type
#define fl6_gre_key             uli.gre_key
        __u32                   mp_hash;
} __attribute__((__aligned__(BITS_PER_LONG/8)));

struct flowi {
        union {
                struct flowi_common     __fl_common;
                struct flowi4           ip4;
                struct flowi6           ip6;
        } u;
#define flowi_oif       u.__fl_common.flowic_oif
#define flowi_iif       u.__fl_common.flowic_iif
#define flowi_l3mdev    u.__fl_common.flowic_l3mdev
#define flowi_mark      u.__fl_common.flowic_mark
#define flowi_dscp      u.__fl_common.flowic_dscp
#define flowi_scope     u.__fl_common.flowic_scope
#define flowi_proto     u.__fl_common.flowic_proto
#define flowi_flags     u.__fl_common.flowic_flags
#define flowi_secid     u.__fl_common.flowic_secid
#define flowi_tun_key   u.__fl_common.flowic_tun_key
#define flowi_uid       u.__fl_common.flowic_uid
} __attribute__((__aligned__(BITS_PER_LONG/8)));

static inline struct flowi *flowi4_to_flowi(struct flowi4 *fl4)
{
        return container_of(fl4, struct flowi, u.ip4);
}

static inline struct flowi_common *flowi4_to_flowi_common(struct flowi4 *fl4)
{
        return &(fl4->__fl_common);
}

static inline struct flowi *flowi6_to_flowi(struct flowi6 *fl6)
{
        return container_of(fl6, struct flowi, u.ip6);
}

static inline struct flowi_common *flowi6_to_flowi_common(struct flowi6 *fl6)
{
        return &(fl6->__fl_common);
}

__u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys);

#endif