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/* SPDX-License-Identifier: GPL-2.0 */
#ifndef __BPF_API__
#define __BPF_API__
/* Note:
*
* This file can be included into eBPF kernel programs. It contains
* a couple of useful helper functions, map/section ABI (bpf_elf.h),
* misc macros and some eBPF specific LLVM built-ins.
*/
#include <stdint.h>
#include <linux/pkt_cls.h>
#include <linux/bpf.h>
#include <linux/filter.h>
#include <asm/byteorder.h>
#include "bpf_elf.h"
/** libbpf pin type. */
enum libbpf_pin_type {
LIBBPF_PIN_NONE,
/* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
LIBBPF_PIN_BY_NAME,
};
/** Type helper macros. */
#define __uint(name, val) int (*name)[val]
#define __type(name, val) typeof(val) *name
#define __array(name, val) typeof(val) *name[]
/** Misc macros. */
#ifndef __stringify
# define __stringify(X) #X
#endif
#ifndef __maybe_unused
# define __maybe_unused __attribute__((__unused__))
#endif
#ifndef offsetof
# define offsetof(TYPE, MEMBER) __builtin_offsetof(TYPE, MEMBER)
#endif
#ifndef likely
# define likely(X) __builtin_expect(!!(X), 1)
#endif
#ifndef unlikely
# define unlikely(X) __builtin_expect(!!(X), 0)
#endif
#ifndef htons
# define htons(X) __constant_htons((X))
#endif
#ifndef ntohs
# define ntohs(X) __constant_ntohs((X))
#endif
#ifndef htonl
# define htonl(X) __constant_htonl((X))
#endif
#ifndef ntohl
# define ntohl(X) __constant_ntohl((X))
#endif
#ifndef __inline__
# define __inline__ __attribute__((always_inline))
#endif
/** Section helper macros. */
#ifndef __section
# define __section(NAME) \
__attribute__((section(NAME), used))
#endif
#ifndef __section_tail
# define __section_tail(ID, KEY) \
__section(__stringify(ID) "/" __stringify(KEY))
#endif
#ifndef __section_xdp_entry
# define __section_xdp_entry \
__section(ELF_SECTION_PROG)
#endif
#ifndef __section_cls_entry
# define __section_cls_entry \
__section(ELF_SECTION_CLASSIFIER)
#endif
#ifndef __section_act_entry
# define __section_act_entry \
__section(ELF_SECTION_ACTION)
#endif
#ifndef __section_lwt_entry
# define __section_lwt_entry \
__section(ELF_SECTION_PROG)
#endif
#ifndef __section_license
# define __section_license \
__section(ELF_SECTION_LICENSE)
#endif
#ifndef __section_maps
# define __section_maps \
__section(ELF_SECTION_MAPS)
#endif
/** Declaration helper macros. */
#ifndef BPF_LICENSE
# define BPF_LICENSE(NAME) \
char ____license[] __section_license = NAME
#endif
/** Classifier helper */
#ifndef BPF_H_DEFAULT
# define BPF_H_DEFAULT -1
#endif
/** BPF helper functions for tc. Individual flags are in linux/bpf.h */
#ifndef __BPF_FUNC
# define __BPF_FUNC(NAME, ...) \
(* NAME)(__VA_ARGS__) __maybe_unused
#endif
#ifndef BPF_FUNC
# define BPF_FUNC(NAME, ...) \
__BPF_FUNC(NAME, __VA_ARGS__) = (void *) BPF_FUNC_##NAME
#endif
/* Map access/manipulation */
static void *BPF_FUNC(map_lookup_elem, void *map, const void *key);
static int BPF_FUNC(map_update_elem, void *map, const void *key,
const void *value, uint32_t flags);
static int BPF_FUNC(map_delete_elem, void *map, const void *key);
/* Time access */
static uint64_t BPF_FUNC(ktime_get_ns);
/* Debugging */
/* FIXME: __attribute__ ((format(printf, 1, 3))) not possible unless
* llvm bug https://llvm.org/bugs/show_bug.cgi?id=26243 gets resolved.
* It would require ____fmt to be made const, which generates a reloc
* entry (non-map).
*/
static void BPF_FUNC(trace_printk, const char *fmt, int fmt_size, ...);
#ifndef printt
# define printt(fmt, ...) \
({ \
char ____fmt[] = fmt; \
trace_printk(____fmt, sizeof(____fmt), ##__VA_ARGS__); \
})
#endif
/* Random numbers */
static uint32_t BPF_FUNC(get_prandom_u32);
/* Tail calls */
static void BPF_FUNC(tail_call, struct __sk_buff *skb, void *map,
uint32_t index);
/* System helpers */
static uint32_t BPF_FUNC(get_smp_processor_id);
static uint32_t BPF_FUNC(get_numa_node_id);
/* Packet misc meta data */
static uint32_t BPF_FUNC(get_cgroup_classid, struct __sk_buff *skb);
static int BPF_FUNC(skb_under_cgroup, void *map, uint32_t index);
static uint32_t BPF_FUNC(get_route_realm, struct __sk_buff *skb);
static uint32_t BPF_FUNC(get_hash_recalc, struct __sk_buff *skb);
static uint32_t BPF_FUNC(set_hash_invalid, struct __sk_buff *skb);
/* Packet redirection */
static int BPF_FUNC(redirect, int ifindex, uint32_t flags);
static int BPF_FUNC(clone_redirect, struct __sk_buff *skb, int ifindex,
uint32_t flags);
/* Packet manipulation */
static int BPF_FUNC(skb_load_bytes, struct __sk_buff *skb, uint32_t off,
void *to, uint32_t len);
static int BPF_FUNC(skb_store_bytes, struct __sk_buff *skb, uint32_t off,
const void *from, uint32_t len, uint32_t flags);
static int BPF_FUNC(l3_csum_replace, struct __sk_buff *skb, uint32_t off,
uint32_t from, uint32_t to, uint32_t flags);
static int BPF_FUNC(l4_csum_replace, struct __sk_buff *skb, uint32_t off,
uint32_t from, uint32_t to, uint32_t flags);
static int BPF_FUNC(csum_diff, const void *from, uint32_t from_size,
const void *to, uint32_t to_size, uint32_t seed);
static int BPF_FUNC(csum_update, struct __sk_buff *skb, uint32_t wsum);
static int BPF_FUNC(skb_change_type, struct __sk_buff *skb, uint32_t type);
static int BPF_FUNC(skb_change_proto, struct __sk_buff *skb, uint32_t proto,
uint32_t flags);
static int BPF_FUNC(skb_change_tail, struct __sk_buff *skb, uint32_t nlen,
uint32_t flags);
static int BPF_FUNC(skb_pull_data, struct __sk_buff *skb, uint32_t len);
/* Event notification */
static int __BPF_FUNC(skb_event_output, struct __sk_buff *skb, void *map,
uint64_t index, const void *data, uint32_t size) =
(void *) BPF_FUNC_perf_event_output;
/* Packet vlan encap/decap */
static int BPF_FUNC(skb_vlan_push, struct __sk_buff *skb, uint16_t proto,
uint16_t vlan_tci);
static int BPF_FUNC(skb_vlan_pop, struct __sk_buff *skb);
/* Packet tunnel encap/decap */
static int BPF_FUNC(skb_get_tunnel_key, struct __sk_buff *skb,
struct bpf_tunnel_key *to, uint32_t size, uint32_t flags);
static int BPF_FUNC(skb_set_tunnel_key, struct __sk_buff *skb,
const struct bpf_tunnel_key *from, uint32_t size,
uint32_t flags);
static int BPF_FUNC(skb_get_tunnel_opt, struct __sk_buff *skb,
void *to, uint32_t size);
static int BPF_FUNC(skb_set_tunnel_opt, struct __sk_buff *skb,
const void *from, uint32_t size);
/** LLVM built-ins, mem*() routines work for constant size */
#ifndef lock_xadd
# define lock_xadd(ptr, val) ((void) __sync_fetch_and_add(ptr, val))
#endif
#ifndef memset
# define memset(s, c, n) __builtin_memset((s), (c), (n))
#endif
#ifndef memcpy
# define memcpy(d, s, n) __builtin_memcpy((d), (s), (n))
#endif
#ifndef memmove
# define memmove(d, s, n) __builtin_memmove((d), (s), (n))
#endif
/* FIXME: __builtin_memcmp() is not yet fully useable unless llvm bug
* https://llvm.org/bugs/show_bug.cgi?id=26218 gets resolved. Also
* this one would generate a reloc entry (non-map), otherwise.
*/
#if 0
#ifndef memcmp
# define memcmp(a, b, n) __builtin_memcmp((a), (b), (n))
#endif
#endif
unsigned long long load_byte(void *skb, unsigned long long off)
asm ("llvm.bpf.load.byte");
unsigned long long load_half(void *skb, unsigned long long off)
asm ("llvm.bpf.load.half");
unsigned long long load_word(void *skb, unsigned long long off)
asm ("llvm.bpf.load.word");
#endif /* __BPF_API__ */
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