/* SPDX-License-Identifier: GPL-2.0 */
/* Minimal BPF type stubs for RVF eBPF programs.
 *
 * This header provides the essential kernel type definitions so that
 * BPF C programs can compile without requiring the full kernel headers.
 * In production, replace this with the vmlinux.h generated by:
 *   bpftool btf dump file /sys/kernel/btf/vmlinux format c
 */

#ifndef __VMLINUX_H__
#define __VMLINUX_H__

/* ── Scalar typedefs ─────────────────────────────────────────────── */

typedef unsigned char       __u8;
typedef unsigned short      __u16;
typedef unsigned int        __u32;
typedef unsigned long long  __u64;
typedef signed char         __s8;
typedef signed short        __s16;
typedef signed int          __s32;
typedef signed long long    __s64;

typedef __u16 __be16;
typedef __u32 __be32;
typedef __u64 __be64;

typedef __u16 __sum16;

/* ── Ethernet ────────────────────────────────────────────────────── */

#define ETH_ALEN    6
#define ETH_P_IP    0x0800
#define ETH_P_IPV6  0x86DD

struct ethhdr {
    unsigned char   h_dest[ETH_ALEN];
    unsigned char   h_source[ETH_ALEN];
    __be16          h_proto;
} __attribute__((packed));

/* ── IPv4 ────────────────────────────────────────────────────────── */

#define IPPROTO_TCP   6
#define IPPROTO_UDP  17

struct iphdr {
#if defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
    __u8  ihl:4,
          version:4;
#else
    __u8  version:4,
          ihl:4;
#endif
    __u8  tos;
    __be16 tot_len;
    __be16 id;
    __be16 frag_off;
    __u8   ttl;
    __u8   protocol;
    __sum16 check;
    __be32  saddr;
    __be32  daddr;
} __attribute__((packed));

/* ── UDP ─────────────────────────────────────────────────────────── */

struct udphdr {
    __be16 source;
    __be16 dest;
    __be16 len;
    __sum16 check;
} __attribute__((packed));

/* ── TCP ─────────────────────────────────────────────────────────── */

struct tcphdr {
    __be16 source;
    __be16 dest;
    __be32 seq;
    __be32 ack_seq;
#if defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__
    __u16  res1:4,
           doff:4,
           fin:1,
           syn:1,
           rst:1,
           psh:1,
           ack:1,
           urg:1,
           ece:1,
           cwr:1;
#else
    __u16  doff:4,
           res1:4,
           cwr:1,
           ece:1,
           urg:1,
           ack:1,
           psh:1,
           rst:1,
           syn:1,
           fin:1;
#endif
    __be16 window;
    __sum16 check;
    __be16 urg_ptr;
} __attribute__((packed));

/* ── XDP context ─────────────────────────────────────────────────── */

struct xdp_md {
    __u32 data;
    __u32 data_end;
    __u32 data_meta;
    __u32 ingress_ifindex;
    __u32 rx_queue_index;
    __u32 egress_ifindex;
};

/* XDP return codes */
#define XDP_ABORTED  0
#define XDP_DROP     1
#define XDP_PASS     2
#define XDP_TX       3
#define XDP_REDIRECT 4

/* ── TC (Traffic Control) context ────────────────────────────────── */

struct __sk_buff {
    __u32 len;
    __u32 pkt_type;
    __u32 mark;
    __u32 queue_mapping;
    __u32 protocol;
    __u32 vlan_present;
    __u32 vlan_tci;
    __u32 vlan_proto;
    __u32 priority;
    __u32 ingress_ifindex;
    __u32 ifindex;
    __u32 tc_index;
    __u32 cb[5];
    __u32 hash;
    __u32 tc_classid;
    __u32 data;
    __u32 data_end;
    __u32 napi_id;
    __u32 family;
    __u32 remote_ip4;
    __u32 local_ip4;
    __u32 remote_ip6[4];
    __u32 local_ip6[4];
    __u32 remote_port;
    __u32 local_port;
    __u32 data_meta;
};

/* TC action return codes */
#define TC_ACT_UNSPEC    (-1)
#define TC_ACT_OK         0
#define TC_ACT_RECLASSIFY 1
#define TC_ACT_SHOT       2
#define TC_ACT_PIPE       3
#define TC_ACT_STOLEN     4
#define TC_ACT_QUEUED     5
#define TC_ACT_REPEAT     6
#define TC_ACT_REDIRECT   7

/* ── BPF map type constants ──────────────────────────────────────── */

#define BPF_MAP_TYPE_HASH            1
#define BPF_MAP_TYPE_ARRAY           2
#define BPF_MAP_TYPE_PERCPU_ARRAY    6
#define BPF_MAP_TYPE_LRU_HASH       9

/* ── BPF helper function declarations ────────────────────────────── */

/* SEC / __always_inline macros (if not using bpf/bpf_helpers.h) */
#ifndef SEC
#define SEC(name) \
    _Pragma("GCC diagnostic push")                      \
    _Pragma("GCC diagnostic ignored \"-Wignored-attributes\"") \
    __attribute__((section(name), used))                \
    _Pragma("GCC diagnostic pop")
#endif

#ifndef __always_inline
#define __always_inline inline __attribute__((always_inline))
#endif

#ifndef __uint
#define __uint(name, val)  int (*name)[val]
#endif

#ifndef __type
#define __type(name, val)  typeof(val) *name
#endif

/* ── BPF helper IDs (from linux/bpf.h) ──────────────────────────── */

static void *(*bpf_map_lookup_elem)(void *map, const void *key) = (void *) 1;
static long (*bpf_map_update_elem)(void *map, const void *key,
                                   const void *value, __u64 flags) = (void *) 2;
static long (*bpf_map_delete_elem)(void *map, const void *key) = (void *) 3;
static __u64 (*bpf_ktime_get_ns)(void) = (void *) 5;
static long (*bpf_trace_printk)(const char *fmt, __u32 fmt_size, ...) = (void *) 6;
static __u32 (*bpf_get_smp_processor_id)(void) = (void *) 8;
static long (*bpf_skb_store_bytes)(struct __sk_buff *skb, __u32 offset,
                                   const void *from, __u32 len,
                                   __u64 flags) = (void *) 9;
static long (*bpf_skb_load_bytes)(const struct __sk_buff *skb, __u32 offset,
                                  void *to, __u32 len) = (void *) 26;
static __u32 (*bpf_get_prandom_u32)(void) = (void *) 7;

/* ── Endian helpers ──────────────────────────────────────────────── */

#ifndef bpf_htons
#define bpf_htons(x)  __builtin_bswap16(x)
#endif

#ifndef bpf_ntohs
#define bpf_ntohs(x)  __builtin_bswap16(x)
#endif

#ifndef bpf_htonl
#define bpf_htonl(x)  __builtin_bswap32(x)
#endif

#ifndef bpf_ntohl
#define bpf_ntohl(x)  __builtin_bswap32(x)
#endif

/* memcpy/memset for BPF -- must use builtins */
#ifndef __bpf_memcpy
#define __bpf_memcpy __builtin_memcpy
#endif

#ifndef __bpf_memset
#define __bpf_memset __builtin_memset
#endif

#endif /* __VMLINUX_H__ */