[mirror_iproute2.git] / include / bpf_api.h

/* 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"

/** 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__ */
Commit	Line	Data
6054c1eb	1	/* SPDX-License-Identifier: GPL-2.0 */
41d6e33f DB	2	#ifndef __BPF_API__
	3	#define __BPF_API__
	4
	5	/* Note:
	6	*
	7	* This file can be included into eBPF kernel programs. It contains
	8	* a couple of useful helper functions, map/section ABI (bpf_elf.h),
	9	* misc macros and some eBPF specific LLVM built-ins.
	10	*/
	11
	12	#include <stdint.h>
	13
	14	#include <linux/pkt_cls.h>
	15	#include <linux/bpf.h>
	16	#include <linux/filter.h>
	17
	18	#include <asm/byteorder.h>
	19
	20	#include "bpf_elf.h"
	21
	22	/** Misc macros. */
	23
	24	#ifndef __stringify
	25	# define __stringify(X) #X
	26	#endif
	27
	28	#ifndef __maybe_unused
	29	# define __maybe_unused __attribute__((__unused__))
	30	#endif
	31
	32	#ifndef offsetof
	33	# define offsetof(TYPE, MEMBER) __builtin_offsetof(TYPE, MEMBER)
	34	#endif
	35
	36	#ifndef likely
	37	# define likely(X) __builtin_expect(!!(X), 1)
	38	#endif
	39
	40	#ifndef unlikely
	41	# define unlikely(X) __builtin_expect(!!(X), 0)
	42	#endif
	43
	44	#ifndef htons
	45	# define htons(X) __constant_htons((X))
	46	#endif
	47
	48	#ifndef ntohs
	49	# define ntohs(X) __constant_ntohs((X))
	50	#endif
	51
	52	#ifndef htonl
	53	# define htonl(X) __constant_htonl((X))
	54	#endif
	55
	56	#ifndef ntohl
fd7f9c7f	57	# define ntohl(X) __constant_ntohl((X))
41d6e33f DB	58	#endif
41d6e33f DB	59
92a36995 DB	60	#ifndef __inline__
	61	# define __inline__ __attribute__((always_inline))
	62	#endif
	63
41d6e33f DB	64	/** Section helper macros. */
	65
	66	#ifndef __section
	67	# define __section(NAME) \
	68	__attribute__((section(NAME), used))
	69	#endif
	70
	71	#ifndef __section_tail
	72	# define __section_tail(ID, KEY) \
	73	__section(__stringify(ID) "/" __stringify(KEY))
	74	#endif
	75
c7272ca7 DB	76	#ifndef __section_xdp_entry
	77	# define __section_xdp_entry \
	78	__section(ELF_SECTION_PROG)
	79	#endif
	80
41d6e33f DB	81	#ifndef __section_cls_entry
	82	# define __section_cls_entry \
	83	__section(ELF_SECTION_CLASSIFIER)
	84	#endif
	85
	86	#ifndef __section_act_entry
	87	# define __section_act_entry \
	88	__section(ELF_SECTION_ACTION)
	89	#endif
	90
b15f440e TG	91	#ifndef __section_lwt_entry
	92	# define __section_lwt_entry \
	93	__section(ELF_SECTION_PROG)
	94	#endif
	95
41d6e33f DB	96	#ifndef __section_license
	97	# define __section_license \
	98	__section(ELF_SECTION_LICENSE)
	99	#endif
	100
	101	#ifndef __section_maps
	102	# define __section_maps \
	103	__section(ELF_SECTION_MAPS)
	104	#endif
	105
	106	/** Declaration helper macros. */
	107
	108	#ifndef BPF_LICENSE
	109	# define BPF_LICENSE(NAME) \
	110	char ____license[] __section_license = NAME
	111	#endif
	112
41d6e33f DB	113	/** Classifier helper */
	114
	115	#ifndef BPF_H_DEFAULT
	116	# define BPF_H_DEFAULT -1
	117	#endif
	118
92a36995	119	/** BPF helper functions for tc. Individual flags are in linux/bpf.h */
41d6e33f	120
e4225669 DB	121	#ifndef __BPF_FUNC
	122	# define __BPF_FUNC(NAME, ...) \
	123	(* NAME)(__VA_ARGS__) __maybe_unused
	124	#endif
	125
41d6e33f DB	126	#ifndef BPF_FUNC
41d6e33f DB	127	# define BPF_FUNC(NAME, ...) \
e4225669	128	__BPF_FUNC(NAME, __VA_ARGS__) = (void *) BPF_FUNC_##NAME
41d6e33f DB	129	#endif
	130
	131	/* Map access/manipulation */
	132	static void BPF_FUNC(map_lookup_elem, void map, const void *key);
	133	static int BPF_FUNC(map_update_elem, void map, const void key,
	134	const void *value, uint32_t flags);
	135	static int BPF_FUNC(map_delete_elem, void map, const void key);
	136
	137	/* Time access */
	138	static uint64_t BPF_FUNC(ktime_get_ns);
	139
	140	/* Debugging */
92a36995 DB	141
	142	/* FIXME: __attribute__ ((format(printf, 1, 3))) not possible unless
	143	* llvm bug https://llvm.org/bugs/show_bug.cgi?id=26243 gets resolved.
	144	* It would require ____fmt to be made const, which generates a reloc
	145	* entry (non-map).
	146	*/
41d6e33f DB	147	static void BPF_FUNC(trace_printk, const char *fmt, int fmt_size, ...);
41d6e33f DB	148
92a36995 DB	149	#ifndef printt
	150	# define printt(fmt, ...) \
	151	({ \
	152	char ____fmt[] = fmt; \
	153	trace_printk(____fmt, sizeof(____fmt), ##__VA_ARGS__); \
	154	})
	155	#endif
	156
41d6e33f DB	157	/* Random numbers */
	158	static uint32_t BPF_FUNC(get_prandom_u32);
	159
	160	/* Tail calls */
	161	static void BPF_FUNC(tail_call, struct __sk_buff skb, void map,
	162	uint32_t index);
	163
	164	/* System helpers */
	165	static uint32_t BPF_FUNC(get_smp_processor_id);
e4225669	166	static uint32_t BPF_FUNC(get_numa_node_id);
41d6e33f DB	167
	168	/* Packet misc meta data */
	169	static uint32_t BPF_FUNC(get_cgroup_classid, struct __sk_buff *skb);
e4225669 DB	170	static int BPF_FUNC(skb_under_cgroup, void *map, uint32_t index);
e4225669 DB	171
41d6e33f	172	static uint32_t BPF_FUNC(get_route_realm, struct __sk_buff *skb);
e4225669 DB	173	static uint32_t BPF_FUNC(get_hash_recalc, struct __sk_buff *skb);
e4225669 DB	174	static uint32_t BPF_FUNC(set_hash_invalid, struct __sk_buff *skb);
41d6e33f DB	175
	176	/* Packet redirection */
	177	static int BPF_FUNC(redirect, int ifindex, uint32_t flags);
	178	static int BPF_FUNC(clone_redirect, struct __sk_buff *skb, int ifindex,
	179	uint32_t flags);
	180
	181	/* Packet manipulation */
92a36995 DB	182	static int BPF_FUNC(skb_load_bytes, struct __sk_buff *skb, uint32_t off,
92a36995 DB	183	void *to, uint32_t len);
41d6e33f	184	static int BPF_FUNC(skb_store_bytes, struct __sk_buff *skb, uint32_t off,
92a36995 DB	185	const void *from, uint32_t len, uint32_t flags);
92a36995 DB	186
41d6e33f DB	187	static int BPF_FUNC(l3_csum_replace, struct __sk_buff *skb, uint32_t off,
	188	uint32_t from, uint32_t to, uint32_t flags);
	189	static int BPF_FUNC(l4_csum_replace, struct __sk_buff *skb, uint32_t off,
	190	uint32_t from, uint32_t to, uint32_t flags);
0395711c DB	191	static int BPF_FUNC(csum_diff, const void *from, uint32_t from_size,
0395711c DB	192	const void *to, uint32_t to_size, uint32_t seed);
e4225669 DB	193	static int BPF_FUNC(csum_update, struct __sk_buff *skb, uint32_t wsum);
	194
	195	static int BPF_FUNC(skb_change_type, struct __sk_buff *skb, uint32_t type);
	196	static int BPF_FUNC(skb_change_proto, struct __sk_buff *skb, uint32_t proto,
	197	uint32_t flags);
	198	static int BPF_FUNC(skb_change_tail, struct __sk_buff *skb, uint32_t nlen,
	199	uint32_t flags);
	200
	201	static int BPF_FUNC(skb_pull_data, struct __sk_buff *skb, uint32_t len);
	202
	203	/* Event notification */
	204	static int __BPF_FUNC(skb_event_output, struct __sk_buff skb, void map,
	205	uint64_t index, const void *data, uint32_t size) =
	206	(void *) BPF_FUNC_perf_event_output;
41d6e33f DB	207
	208	/* Packet vlan encap/decap */
	209	static int BPF_FUNC(skb_vlan_push, struct __sk_buff *skb, uint16_t proto,
	210	uint16_t vlan_tci);
	211	static int BPF_FUNC(skb_vlan_pop, struct __sk_buff *skb);
	212
	213	/* Packet tunnel encap/decap */
	214	static int BPF_FUNC(skb_get_tunnel_key, struct __sk_buff *skb,
	215	struct bpf_tunnel_key *to, uint32_t size, uint32_t flags);
	216	static int BPF_FUNC(skb_set_tunnel_key, struct __sk_buff *skb,
92a36995 DB	217	const struct bpf_tunnel_key *from, uint32_t size,
92a36995 DB	218	uint32_t flags);
41d6e33f	219
0395711c DB	220	static int BPF_FUNC(skb_get_tunnel_opt, struct __sk_buff *skb,
	221	void *to, uint32_t size);
	222	static int BPF_FUNC(skb_set_tunnel_opt, struct __sk_buff *skb,
	223	const void *from, uint32_t size);
	224
92a36995	225	/** LLVM built-ins, mem() routines work for constant size /
41d6e33f DB	226
	227	#ifndef lock_xadd
	228	# define lock_xadd(ptr, val) ((void) __sync_fetch_and_add(ptr, val))
	229	#endif
	230
92a36995 DB	231	#ifndef memset
	232	# define memset(s, c, n) __builtin_memset((s), (c), (n))
	233	#endif
	234
	235	#ifndef memcpy
	236	# define memcpy(d, s, n) __builtin_memcpy((d), (s), (n))
	237	#endif
	238
	239	#ifndef memmove
	240	# define memmove(d, s, n) __builtin_memmove((d), (s), (n))
	241	#endif
	242
	243	/* FIXME: __builtin_memcmp() is not yet fully useable unless llvm bug
	244	* https://llvm.org/bugs/show_bug.cgi?id=26218 gets resolved. Also
	245	* this one would generate a reloc entry (non-map), otherwise.
	246	*/
	247	#if 0
	248	#ifndef memcmp
	249	# define memcmp(a, b, n) __builtin_memcmp((a), (b), (n))
	250	#endif
	251	#endif
	252
41d6e33f DB	253	unsigned long long load_byte(void *skb, unsigned long long off)
	254	asm ("llvm.bpf.load.byte");
	255
	256	unsigned long long load_half(void *skb, unsigned long long off)
	257	asm ("llvm.bpf.load.half");
	258
	259	unsigned long long load_word(void *skb, unsigned long long off)
	260	asm ("llvm.bpf.load.word");
	261
	262	#endif /* __BPF_API__ */