[linux-2.6-block.git] / include / linux / bpf.h

/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of version 2 of the GNU General Public
 * License as published by the Free Software Foundation.
 */
#ifndef _LINUX_BPF_H
#define _LINUX_BPF_H 1

#include <uapi/linux/bpf.h>
#include <linux/workqueue.h>
#include <linux/file.h>
#include <linux/percpu.h>

struct bpf_map;

/* map is generic key/value storage optionally accesible by eBPF programs */
struct bpf_map_ops {
	/* funcs callable from userspace (via syscall) */
	struct bpf_map *(*map_alloc)(union bpf_attr *attr);
	void (*map_free)(struct bpf_map *);
	int (*map_get_next_key)(struct bpf_map *map, void *key, void *next_key);

	/* funcs callable from userspace and from eBPF programs */
	void *(*map_lookup_elem)(struct bpf_map *map, void *key);
	int (*map_update_elem)(struct bpf_map *map, void *key, void *value, u64 flags);
	int (*map_delete_elem)(struct bpf_map *map, void *key);

	/* funcs called by prog_array and perf_event_array map */
	void *(*map_fd_get_ptr) (struct bpf_map *map, int fd);
	void (*map_fd_put_ptr) (void *ptr);
};

struct bpf_map {
	atomic_t refcnt;
	enum bpf_map_type map_type;
	u32 key_size;
	u32 value_size;
	u32 max_entries;
	u32 map_flags;
	u32 pages;
	struct user_struct *user;
	const struct bpf_map_ops *ops;
	struct work_struct work;
	atomic_t usercnt;
};

struct bpf_map_type_list {
	struct list_head list_node;
	const struct bpf_map_ops *ops;
	enum bpf_map_type type;
};

/* function argument constraints */
enum bpf_arg_type {
	ARG_DONTCARE = 0,	/* unused argument in helper function */

	/* the following constraints used to prototype
	 * bpf_map_lookup/update/delete_elem() functions
	 */
	ARG_CONST_MAP_PTR,	/* const argument used as pointer to bpf_map */
	ARG_PTR_TO_MAP_KEY,	/* pointer to stack used as map key */
	ARG_PTR_TO_MAP_VALUE,	/* pointer to stack used as map value */

	/* the following constraints used to prototype bpf_memcmp() and other
	 * functions that access data on eBPF program stack
	 */
	ARG_PTR_TO_STACK,	/* any pointer to eBPF program stack */
	ARG_PTR_TO_RAW_STACK,	/* any pointer to eBPF program stack, area does not
				 * need to be initialized, helper function must fill
				 * all bytes or clear them in error case.
				 */

	ARG_CONST_STACK_SIZE,	/* number of bytes accessed from stack */
	ARG_CONST_STACK_SIZE_OR_ZERO, /* number of bytes accessed from stack or 0 */

	ARG_PTR_TO_CTX,		/* pointer to context */
	ARG_ANYTHING,		/* any (initialized) argument is ok */
};

/* type of values returned from helper functions */
enum bpf_return_type {
	RET_INTEGER,			/* function returns integer */
	RET_VOID,			/* function doesn't return anything */
	RET_PTR_TO_MAP_VALUE_OR_NULL,	/* returns a pointer to map elem value or NULL */
};

/* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
 * to in-kernel helper functions and for adjusting imm32 field in BPF_CALL
 * instructions after verifying
 */
struct bpf_func_proto {
	u64 (*func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
	bool gpl_only;
	enum bpf_return_type ret_type;
	enum bpf_arg_type arg1_type;
	enum bpf_arg_type arg2_type;
	enum bpf_arg_type arg3_type;
	enum bpf_arg_type arg4_type;
	enum bpf_arg_type arg5_type;
};

/* bpf_context is intentionally undefined structure. Pointer to bpf_context is
 * the first argument to eBPF programs.
 * For socket filters: 'struct bpf_context *' == 'struct sk_buff *'
 */
struct bpf_context;

enum bpf_access_type {
	BPF_READ = 1,
	BPF_WRITE = 2
};

struct bpf_prog;

struct bpf_verifier_ops {
	/* return eBPF function prototype for verification */
	const struct bpf_func_proto *(*get_func_proto)(enum bpf_func_id func_id);

	/* return true if 'size' wide access at offset 'off' within bpf_context
	 * with 'type' (read or write) is allowed
	 */
	bool (*is_valid_access)(int off, int size, enum bpf_access_type type);

	u32 (*convert_ctx_access)(enum bpf_access_type type, int dst_reg,
				  int src_reg, int ctx_off,
				  struct bpf_insn *insn, struct bpf_prog *prog);
};

struct bpf_prog_type_list {
	struct list_head list_node;
	const struct bpf_verifier_ops *ops;
	enum bpf_prog_type type;
};

struct bpf_prog_aux {
	atomic_t refcnt;
	u32 used_map_cnt;
	u32 max_ctx_offset;
	const struct bpf_verifier_ops *ops;
	struct bpf_map **used_maps;
	struct bpf_prog *prog;
	struct user_struct *user;
	union {
		struct work_struct work;
		struct rcu_head	rcu;
	};
};

struct bpf_array {
	struct bpf_map map;
	u32 elem_size;
	/* 'ownership' of prog_array is claimed by the first program that
	 * is going to use this map or by the first program which FD is stored
	 * in the map to make sure that all callers and callees have the same
	 * prog_type and JITed flag
	 */
	enum bpf_prog_type owner_prog_type;
	bool owner_jited;
	union {
		char value[0] __aligned(8);
		void *ptrs[0] __aligned(8);
		void __percpu *pptrs[0] __aligned(8);
	};
};
#define MAX_TAIL_CALL_CNT 32

u64 bpf_tail_call(u64 ctx, u64 r2, u64 index, u64 r4, u64 r5);
u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
void bpf_fd_array_map_clear(struct bpf_map *map);
bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp);
const struct bpf_func_proto *bpf_get_trace_printk_proto(void);

#ifdef CONFIG_BPF_SYSCALL
DECLARE_PER_CPU(int, bpf_prog_active);

void bpf_register_prog_type(struct bpf_prog_type_list *tl);
void bpf_register_map_type(struct bpf_map_type_list *tl);

struct bpf_prog *bpf_prog_get(u32 ufd);
void bpf_prog_put(struct bpf_prog *prog);
void bpf_prog_put_rcu(struct bpf_prog *prog);

struct bpf_map *bpf_map_get_with_uref(u32 ufd);
struct bpf_map *__bpf_map_get(struct fd f);
void bpf_map_inc(struct bpf_map *map, bool uref);
void bpf_map_put_with_uref(struct bpf_map *map);
void bpf_map_put(struct bpf_map *map);
int bpf_map_precharge_memlock(u32 pages);

extern int sysctl_unprivileged_bpf_disabled;

int bpf_map_new_fd(struct bpf_map *map);
int bpf_prog_new_fd(struct bpf_prog *prog);

int bpf_obj_pin_user(u32 ufd, const char __user *pathname);
int bpf_obj_get_user(const char __user *pathname);

int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value);
int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value);
int bpf_percpu_hash_update(struct bpf_map *map, void *key, void *value,
			   u64 flags);
int bpf_percpu_array_update(struct bpf_map *map, void *key, void *value,
			    u64 flags);
int bpf_stackmap_copy(struct bpf_map *map, void *key, void *value);

/* memcpy that is used with 8-byte aligned pointers, power-of-8 size and
 * forced to use 'long' read/writes to try to atomically copy long counters.
 * Best-effort only.  No barriers here, since it _will_ race with concurrent
 * updates from BPF programs. Called from bpf syscall and mostly used with
 * size 8 or 16 bytes, so ask compiler to inline it.
 */
static inline void bpf_long_memcpy(void *dst, const void *src, u32 size)
{
	const long *lsrc = src;
	long *ldst = dst;

	size /= sizeof(long);
	while (size--)
		*ldst++ = *lsrc++;
}

/* verify correctness of eBPF program */
int bpf_check(struct bpf_prog **fp, union bpf_attr *attr);
#else
static inline void bpf_register_prog_type(struct bpf_prog_type_list *tl)
{
}

static inline struct bpf_prog *bpf_prog_get(u32 ufd)
{
	return ERR_PTR(-EOPNOTSUPP);
}

static inline void bpf_prog_put(struct bpf_prog *prog)
{
}
#endif /* CONFIG_BPF_SYSCALL */

/* verifier prototypes for helper functions called from eBPF programs */
extern const struct bpf_func_proto bpf_map_lookup_elem_proto;
extern const struct bpf_func_proto bpf_map_update_elem_proto;
extern const struct bpf_func_proto bpf_map_delete_elem_proto;

extern const struct bpf_func_proto bpf_get_prandom_u32_proto;
extern const struct bpf_func_proto bpf_get_smp_processor_id_proto;
extern const struct bpf_func_proto bpf_tail_call_proto;
extern const struct bpf_func_proto bpf_ktime_get_ns_proto;
extern const struct bpf_func_proto bpf_get_current_pid_tgid_proto;
extern const struct bpf_func_proto bpf_get_current_uid_gid_proto;
extern const struct bpf_func_proto bpf_get_current_comm_proto;
extern const struct bpf_func_proto bpf_skb_vlan_push_proto;
extern const struct bpf_func_proto bpf_skb_vlan_pop_proto;
extern const struct bpf_func_proto bpf_get_stackid_proto;

/* Shared helpers among cBPF and eBPF. */
void bpf_user_rnd_init_once(void);
u64 bpf_user_rnd_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);

#endif /* _LINUX_BPF_H */
Commit	Line	Data
99c55f7d AS	1	/* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
	2	*
	3	* This program is free software; you can redistribute it and/or
	4	* modify it under the terms of version 2 of the GNU General Public
	5	* License as published by the Free Software Foundation.
	6	*/
	7	#ifndef _LINUX_BPF_H
	8	#define _LINUX_BPF_H 1
	9
	10	#include <uapi/linux/bpf.h>
	11	#include <linux/workqueue.h>
db20fd2b	12	#include <linux/file.h>
b121d1e7	13	#include <linux/percpu.h>
99c55f7d AS	14
	15	struct bpf_map;
	16
	17	/* map is generic key/value storage optionally accesible by eBPF programs */
	18	struct bpf_map_ops {
	19	/* funcs callable from userspace (via syscall) */
	20	struct bpf_map (map_alloc)(union bpf_attr *attr);
	21	void (map_free)(struct bpf_map );
db20fd2b AS	22	int (map_get_next_key)(struct bpf_map map, void key, void next_key);
	23
	24	/* funcs callable from userspace and from eBPF programs */
	25	void (map_lookup_elem)(struct bpf_map map, void key);
3274f520	26	int (map_update_elem)(struct bpf_map map, void key, void value, u64 flags);
db20fd2b	27	int (map_delete_elem)(struct bpf_map map, void *key);
2a36f0b9 WN	28
	29	/* funcs called by prog_array and perf_event_array map */
	30	void (map_fd_get_ptr) (struct bpf_map *map, int fd);
	31	void (map_fd_put_ptr) (void ptr);
99c55f7d AS	32	};
	33
	34	struct bpf_map {
	35	atomic_t refcnt;
	36	enum bpf_map_type map_type;
	37	u32 key_size;
	38	u32 value_size;
	39	u32 max_entries;
6c905981	40	u32 map_flags;
aaac3ba9 AS	41	u32 pages;
aaac3ba9 AS	42	struct user_struct *user;
a2c83fff	43	const struct bpf_map_ops *ops;
99c55f7d	44	struct work_struct work;
c9da161c	45	atomic_t usercnt;
99c55f7d AS	46	};
	47
	48	struct bpf_map_type_list {
	49	struct list_head list_node;
a2c83fff	50	const struct bpf_map_ops *ops;
99c55f7d AS	51	enum bpf_map_type type;
	52	};
	53
17a52670 AS	54	/* function argument constraints */
17a52670 AS	55	enum bpf_arg_type {
80f1d68c	56	ARG_DONTCARE = 0, /* unused argument in helper function */
17a52670 AS	57
	58	/* the following constraints used to prototype
	59	* bpf_map_lookup/update/delete_elem() functions
	60	*/
	61	ARG_CONST_MAP_PTR, /* const argument used as pointer to bpf_map */
	62	ARG_PTR_TO_MAP_KEY, /* pointer to stack used as map key */
	63	ARG_PTR_TO_MAP_VALUE, /* pointer to stack used as map value */
	64
	65	/* the following constraints used to prototype bpf_memcmp() and other
	66	* functions that access data on eBPF program stack
	67	*/
	68	ARG_PTR_TO_STACK, /* any pointer to eBPF program stack */
435faee1 DB	69	ARG_PTR_TO_RAW_STACK, /* any pointer to eBPF program stack, area does not
	70	* need to be initialized, helper function must fill
	71	* all bytes or clear them in error case.
	72	*/
	73
17a52670	74	ARG_CONST_STACK_SIZE, /* number of bytes accessed from stack */
8e2fe1d9	75	ARG_CONST_STACK_SIZE_OR_ZERO, /* number of bytes accessed from stack or 0 */
80f1d68c	76
608cd71a	77	ARG_PTR_TO_CTX, /* pointer to context */
80f1d68c	78	ARG_ANYTHING, /* any (initialized) argument is ok */
17a52670 AS	79	};
	80
	81	/* type of values returned from helper functions */
	82	enum bpf_return_type {
	83	RET_INTEGER, /* function returns integer */
	84	RET_VOID, /* function doesn't return anything */
	85	RET_PTR_TO_MAP_VALUE_OR_NULL, /* returns a pointer to map elem value or NULL */
	86	};
	87
09756af4 AS	88	/* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
	89	* to in-kernel helper functions and for adjusting imm32 field in BPF_CALL
	90	* instructions after verifying
	91	*/
	92	struct bpf_func_proto {
	93	u64 (*func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
	94	bool gpl_only;
17a52670 AS	95	enum bpf_return_type ret_type;
	96	enum bpf_arg_type arg1_type;
	97	enum bpf_arg_type arg2_type;
	98	enum bpf_arg_type arg3_type;
	99	enum bpf_arg_type arg4_type;
	100	enum bpf_arg_type arg5_type;
	101	};
	102
	103	/* bpf_context is intentionally undefined structure. Pointer to bpf_context is
	104	* the first argument to eBPF programs.
	105	* For socket filters: 'struct bpf_context ' == 'struct sk_buff '
	106	*/
	107	struct bpf_context;
	108
	109	enum bpf_access_type {
	110	BPF_READ = 1,
	111	BPF_WRITE = 2
09756af4 AS	112	};
09756af4 AS	113
ff936a04 AS	114	struct bpf_prog;
ff936a04 AS	115
09756af4 AS	116	struct bpf_verifier_ops {
	117	/* return eBPF function prototype for verification */
	118	const struct bpf_func_proto (get_func_proto)(enum bpf_func_id func_id);
17a52670 AS	119
	120	/* return true if 'size' wide access at offset 'off' within bpf_context
	121	* with 'type' (read or write) is allowed
	122	*/
	123	bool (*is_valid_access)(int off, int size, enum bpf_access_type type);
9bac3d6d	124
d691f9e8 AS	125	u32 (*convert_ctx_access)(enum bpf_access_type type, int dst_reg,
d691f9e8 AS	126	int src_reg, int ctx_off,
ff936a04	127	struct bpf_insn insn, struct bpf_prog prog);
09756af4 AS	128	};
	129
	130	struct bpf_prog_type_list {
	131	struct list_head list_node;
a2c83fff	132	const struct bpf_verifier_ops *ops;
09756af4 AS	133	enum bpf_prog_type type;
	134	};
	135
09756af4 AS	136	struct bpf_prog_aux {
09756af4 AS	137	atomic_t refcnt;
24701ece	138	u32 used_map_cnt;
32bbe007	139	u32 max_ctx_offset;
a2c83fff	140	const struct bpf_verifier_ops *ops;
09756af4	141	struct bpf_map **used_maps;
09756af4	142	struct bpf_prog *prog;
aaac3ba9	143	struct user_struct *user;
abf2e7d6 AS	144	union {
	145	struct work_struct work;
	146	struct rcu_head rcu;
	147	};
09756af4 AS	148	};
09756af4 AS	149
04fd61ab AS	150	struct bpf_array {
	151	struct bpf_map map;
	152	u32 elem_size;
	153	/* 'ownership' of prog_array is claimed by the first program that
	154	* is going to use this map or by the first program which FD is stored
	155	* in the map to make sure that all callers and callees have the same
	156	* prog_type and JITed flag
	157	*/
	158	enum bpf_prog_type owner_prog_type;
	159	bool owner_jited;
	160	union {
	161	char value[0] __aligned(8);
2a36f0b9	162	void *ptrs[0] __aligned(8);
a10423b8	163	void __percpu *pptrs[0] __aligned(8);
04fd61ab AS	164	};
	165	};
	166	#define MAX_TAIL_CALL_CNT 32
	167
	168	u64 bpf_tail_call(u64 ctx, u64 r2, u64 index, u64 r4, u64 r5);
9940d67c	169	u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
2a36f0b9	170	void bpf_fd_array_map_clear(struct bpf_map *map);
04fd61ab	171	bool bpf_prog_array_compatible(struct bpf_array array, const struct bpf_prog fp);
0756ea3e	172	const struct bpf_func_proto *bpf_get_trace_printk_proto(void);
04fd61ab	173
89aa0758	174	#ifdef CONFIG_BPF_SYSCALL
b121d1e7 AS	175	DECLARE_PER_CPU(int, bpf_prog_active);
b121d1e7 AS	176
0fc174de	177	void bpf_register_prog_type(struct bpf_prog_type_list *tl);
61e021f3	178	void bpf_register_map_type(struct bpf_map_type_list *tl);
0fc174de	179
0fc174de	180	struct bpf_prog *bpf_prog_get(u32 ufd);
61e021f3	181	void bpf_prog_put(struct bpf_prog *prog);
abf2e7d6	182	void bpf_prog_put_rcu(struct bpf_prog *prog);
61e021f3	183
c9da161c	184	struct bpf_map *bpf_map_get_with_uref(u32 ufd);
c2101297	185	struct bpf_map *__bpf_map_get(struct fd f);
c9da161c DB	186	void bpf_map_inc(struct bpf_map *map, bool uref);
c9da161c DB	187	void bpf_map_put_with_uref(struct bpf_map *map);
61e021f3	188	void bpf_map_put(struct bpf_map *map);
6c905981	189	int bpf_map_precharge_memlock(u32 pages);
61e021f3	190
1be7f75d AS	191	extern int sysctl_unprivileged_bpf_disabled;
1be7f75d AS	192
b2197755 DB	193	int bpf_map_new_fd(struct bpf_map *map);
	194	int bpf_prog_new_fd(struct bpf_prog *prog);
	195
	196	int bpf_obj_pin_user(u32 ufd, const char __user *pathname);
	197	int bpf_obj_get_user(const char __user *pathname);
	198
15a07b33 AS	199	int bpf_percpu_hash_copy(struct bpf_map map, void key, void *value);
	200	int bpf_percpu_array_copy(struct bpf_map map, void key, void *value);
	201	int bpf_percpu_hash_update(struct bpf_map map, void key, void *value,
	202	u64 flags);
	203	int bpf_percpu_array_update(struct bpf_map map, void key, void *value,
	204	u64 flags);
557c0c6e	205	int bpf_stackmap_copy(struct bpf_map map, void key, void *value);
15a07b33 AS	206
	207	/* memcpy that is used with 8-byte aligned pointers, power-of-8 size and
	208	* forced to use 'long' read/writes to try to atomically copy long counters.
	209	* Best-effort only. No barriers here, since it _will_ race with concurrent
	210	* updates from BPF programs. Called from bpf syscall and mostly used with
	211	* size 8 or 16 bytes, so ask compiler to inline it.
	212	*/
	213	static inline void bpf_long_memcpy(void dst, const void src, u32 size)
	214	{
	215	const long *lsrc = src;
	216	long *ldst = dst;
	217
	218	size /= sizeof(long);
	219	while (size--)
	220	ldst++ = lsrc++;
	221	}
	222
61e021f3	223	/* verify correctness of eBPF program */
9bac3d6d	224	int bpf_check(struct bpf_prog *fp, union bpf_attr attr);
89aa0758	225	#else
0fc174de DB	226	static inline void bpf_register_prog_type(struct bpf_prog_type_list *tl)
	227	{
	228	}
	229
	230	static inline struct bpf_prog *bpf_prog_get(u32 ufd)
	231	{
	232	return ERR_PTR(-EOPNOTSUPP);
	233	}
	234
	235	static inline void bpf_prog_put(struct bpf_prog *prog)
	236	{
	237	}
61e021f3	238	#endif /* CONFIG_BPF_SYSCALL */
09756af4	239
d0003ec0	240	/* verifier prototypes for helper functions called from eBPF programs */
a2c83fff DB	241	extern const struct bpf_func_proto bpf_map_lookup_elem_proto;
	242	extern const struct bpf_func_proto bpf_map_update_elem_proto;
	243	extern const struct bpf_func_proto bpf_map_delete_elem_proto;
d0003ec0	244
03e69b50	245	extern const struct bpf_func_proto bpf_get_prandom_u32_proto;
c04167ce	246	extern const struct bpf_func_proto bpf_get_smp_processor_id_proto;
04fd61ab	247	extern const struct bpf_func_proto bpf_tail_call_proto;
17ca8cbf	248	extern const struct bpf_func_proto bpf_ktime_get_ns_proto;
ffeedafb AS	249	extern const struct bpf_func_proto bpf_get_current_pid_tgid_proto;
	250	extern const struct bpf_func_proto bpf_get_current_uid_gid_proto;
	251	extern const struct bpf_func_proto bpf_get_current_comm_proto;
4e10df9a AS	252	extern const struct bpf_func_proto bpf_skb_vlan_push_proto;
4e10df9a AS	253	extern const struct bpf_func_proto bpf_skb_vlan_pop_proto;
d5a3b1f6	254	extern const struct bpf_func_proto bpf_get_stackid_proto;
03e69b50	255
3ad00405 DB	256	/* Shared helpers among cBPF and eBPF. */
	257	void bpf_user_rnd_init_once(void);
	258	u64 bpf_user_rnd_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
	259
99c55f7d	260	#endif /* _LINUX_BPF_H */