[mirror_iproute2.git] / include / bpf_api.h

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