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bpf: split bpf core interpreter
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CommitLineData
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>
74451e66 11
99c55f7d 12#include <linux/workqueue.h>
db20fd2b 13#include <linux/file.h>
b121d1e7 14#include <linux/percpu.h>
002245cc 15#include <linux/err.h>
74451e66 16#include <linux/rbtree_latch.h>
99c55f7d 17
3b1efb19 18struct perf_event;
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AS
19struct bpf_map;
20
21/* map is generic key/value storage optionally accesible by eBPF programs */
22struct bpf_map_ops {
23 /* funcs callable from userspace (via syscall) */
24 struct bpf_map *(*map_alloc)(union bpf_attr *attr);
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DB
25 void (*map_release)(struct bpf_map *map, struct file *map_file);
26 void (*map_free)(struct bpf_map *map);
db20fd2b
AS
27 int (*map_get_next_key)(struct bpf_map *map, void *key, void *next_key);
28
29 /* funcs callable from userspace and from eBPF programs */
30 void *(*map_lookup_elem)(struct bpf_map *map, void *key);
3274f520 31 int (*map_update_elem)(struct bpf_map *map, void *key, void *value, u64 flags);
db20fd2b 32 int (*map_delete_elem)(struct bpf_map *map, void *key);
2a36f0b9
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33
34 /* funcs called by prog_array and perf_event_array map */
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DB
35 void *(*map_fd_get_ptr)(struct bpf_map *map, struct file *map_file,
36 int fd);
37 void (*map_fd_put_ptr)(void *ptr);
81ed18ab 38 u32 (*map_gen_lookup)(struct bpf_map *map, struct bpf_insn *insn_buf);
99c55f7d
AS
39};
40
41struct bpf_map {
42 atomic_t refcnt;
43 enum bpf_map_type map_type;
44 u32 key_size;
45 u32 value_size;
46 u32 max_entries;
6c905981 47 u32 map_flags;
aaac3ba9
AS
48 u32 pages;
49 struct user_struct *user;
a2c83fff 50 const struct bpf_map_ops *ops;
99c55f7d 51 struct work_struct work;
c9da161c 52 atomic_t usercnt;
56f668df 53 struct bpf_map *inner_map_meta;
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AS
54};
55
17a52670
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56/* function argument constraints */
57enum bpf_arg_type {
80f1d68c 58 ARG_DONTCARE = 0, /* unused argument in helper function */
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59
60 /* the following constraints used to prototype
61 * bpf_map_lookup/update/delete_elem() functions
62 */
63 ARG_CONST_MAP_PTR, /* const argument used as pointer to bpf_map */
64 ARG_PTR_TO_MAP_KEY, /* pointer to stack used as map key */
65 ARG_PTR_TO_MAP_VALUE, /* pointer to stack used as map value */
66
67 /* the following constraints used to prototype bpf_memcmp() and other
68 * functions that access data on eBPF program stack
69 */
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70 ARG_PTR_TO_MEM, /* pointer to valid memory (stack, packet, map value) */
71 ARG_PTR_TO_UNINIT_MEM, /* pointer to memory does not need to be initialized,
72 * helper function must fill all bytes or clear
73 * them in error case.
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74 */
75
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76 ARG_CONST_SIZE, /* number of bytes accessed from memory */
77 ARG_CONST_SIZE_OR_ZERO, /* number of bytes accessed from memory or 0 */
80f1d68c 78
608cd71a 79 ARG_PTR_TO_CTX, /* pointer to context */
80f1d68c 80 ARG_ANYTHING, /* any (initialized) argument is ok */
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AS
81};
82
83/* type of values returned from helper functions */
84enum bpf_return_type {
85 RET_INTEGER, /* function returns integer */
86 RET_VOID, /* function doesn't return anything */
87 RET_PTR_TO_MAP_VALUE_OR_NULL, /* returns a pointer to map elem value or NULL */
88};
89
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AS
90/* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
91 * to in-kernel helper functions and for adjusting imm32 field in BPF_CALL
92 * instructions after verifying
93 */
94struct bpf_func_proto {
95 u64 (*func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
96 bool gpl_only;
36bbef52 97 bool pkt_access;
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AS
98 enum bpf_return_type ret_type;
99 enum bpf_arg_type arg1_type;
100 enum bpf_arg_type arg2_type;
101 enum bpf_arg_type arg3_type;
102 enum bpf_arg_type arg4_type;
103 enum bpf_arg_type arg5_type;
104};
105
106/* bpf_context is intentionally undefined structure. Pointer to bpf_context is
107 * the first argument to eBPF programs.
108 * For socket filters: 'struct bpf_context *' == 'struct sk_buff *'
109 */
110struct bpf_context;
111
112enum bpf_access_type {
113 BPF_READ = 1,
114 BPF_WRITE = 2
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115};
116
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117/* types of values stored in eBPF registers */
118enum bpf_reg_type {
119 NOT_INIT = 0, /* nothing was written into register */
120 UNKNOWN_VALUE, /* reg doesn't contain a valid pointer */
121 PTR_TO_CTX, /* reg points to bpf_context */
122 CONST_PTR_TO_MAP, /* reg points to struct bpf_map */
123 PTR_TO_MAP_VALUE, /* reg points to map element value */
124 PTR_TO_MAP_VALUE_OR_NULL,/* points to map elem value or NULL */
125 FRAME_PTR, /* reg == frame_pointer */
126 PTR_TO_STACK, /* reg == frame_pointer + imm */
127 CONST_IMM, /* constant integer value */
128
129 /* PTR_TO_PACKET represents:
130 * skb->data
131 * skb->data + imm
132 * skb->data + (u16) var
133 * skb->data + (u16) var + imm
134 * if (range > 0) then [ptr, ptr + range - off) is safe to access
135 * if (id > 0) means that some 'var' was added
136 * if (off > 0) menas that 'imm' was added
137 */
138 PTR_TO_PACKET,
139 PTR_TO_PACKET_END, /* skb->data + headlen */
48461135
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140
141 /* PTR_TO_MAP_VALUE_ADJ is used for doing pointer math inside of a map
142 * elem value. We only allow this if we can statically verify that
143 * access from this register are going to fall within the size of the
144 * map element.
145 */
146 PTR_TO_MAP_VALUE_ADJ,
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147};
148
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149struct bpf_prog;
150
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151struct bpf_verifier_ops {
152 /* return eBPF function prototype for verification */
153 const struct bpf_func_proto *(*get_func_proto)(enum bpf_func_id func_id);
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154
155 /* return true if 'size' wide access at offset 'off' within bpf_context
156 * with 'type' (read or write) is allowed
157 */
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158 bool (*is_valid_access)(int off, int size, enum bpf_access_type type,
159 enum bpf_reg_type *reg_type);
36bbef52
DB
160 int (*gen_prologue)(struct bpf_insn *insn, bool direct_write,
161 const struct bpf_prog *prog);
6b8cc1d1
DB
162 u32 (*convert_ctx_access)(enum bpf_access_type type,
163 const struct bpf_insn *src,
164 struct bpf_insn *dst,
165 struct bpf_prog *prog);
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AS
166 int (*test_run)(struct bpf_prog *prog, const union bpf_attr *kattr,
167 union bpf_attr __user *uattr);
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AS
168};
169
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170struct bpf_prog_aux {
171 atomic_t refcnt;
24701ece 172 u32 used_map_cnt;
32bbe007 173 u32 max_ctx_offset;
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DB
174 struct latch_tree_node ksym_tnode;
175 struct list_head ksym_lnode;
a2c83fff 176 const struct bpf_verifier_ops *ops;
09756af4 177 struct bpf_map **used_maps;
09756af4 178 struct bpf_prog *prog;
aaac3ba9 179 struct user_struct *user;
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AS
180 union {
181 struct work_struct work;
182 struct rcu_head rcu;
183 };
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184};
185
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186struct bpf_array {
187 struct bpf_map map;
188 u32 elem_size;
189 /* 'ownership' of prog_array is claimed by the first program that
190 * is going to use this map or by the first program which FD is stored
191 * in the map to make sure that all callers and callees have the same
192 * prog_type and JITed flag
193 */
194 enum bpf_prog_type owner_prog_type;
195 bool owner_jited;
196 union {
197 char value[0] __aligned(8);
2a36f0b9 198 void *ptrs[0] __aligned(8);
a10423b8 199 void __percpu *pptrs[0] __aligned(8);
04fd61ab
AS
200 };
201};
3b1efb19 202
04fd61ab
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203#define MAX_TAIL_CALL_CNT 32
204
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DB
205struct bpf_event_entry {
206 struct perf_event *event;
207 struct file *perf_file;
208 struct file *map_file;
209 struct rcu_head rcu;
210};
211
04fd61ab 212u64 bpf_tail_call(u64 ctx, u64 r2, u64 index, u64 r4, u64 r5);
9940d67c 213u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
d056a788 214
04fd61ab 215bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp);
f1f7714e 216int bpf_prog_calc_tag(struct bpf_prog *fp);
bd570ff9 217
0756ea3e 218const struct bpf_func_proto *bpf_get_trace_printk_proto(void);
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DB
219
220typedef unsigned long (*bpf_ctx_copy_t)(void *dst, const void *src,
aa7145c1 221 unsigned long off, unsigned long len);
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DB
222
223u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
224 void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy);
04fd61ab 225
1cf1cae9
AS
226int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
227 union bpf_attr __user *uattr);
228int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
229 union bpf_attr __user *uattr);
230
89aa0758 231#ifdef CONFIG_BPF_SYSCALL
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AS
232DECLARE_PER_CPU(int, bpf_prog_active);
233
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JB
234#define BPF_PROG_TYPE(_id, _ops) \
235 extern const struct bpf_verifier_ops _ops;
40077e0c
JB
236#define BPF_MAP_TYPE(_id, _ops) \
237 extern const struct bpf_map_ops _ops;
be9370a7
JB
238#include <linux/bpf_types.h>
239#undef BPF_PROG_TYPE
40077e0c 240#undef BPF_MAP_TYPE
0fc174de 241
0fc174de 242struct bpf_prog *bpf_prog_get(u32 ufd);
113214be 243struct bpf_prog *bpf_prog_get_type(u32 ufd, enum bpf_prog_type type);
6d67942d 244struct bpf_prog * __must_check bpf_prog_add(struct bpf_prog *prog, int i);
c540594f 245void bpf_prog_sub(struct bpf_prog *prog, int i);
6d67942d 246struct bpf_prog * __must_check bpf_prog_inc(struct bpf_prog *prog);
61e021f3 247void bpf_prog_put(struct bpf_prog *prog);
5ccb071e
DB
248int __bpf_prog_charge(struct user_struct *user, u32 pages);
249void __bpf_prog_uncharge(struct user_struct *user, u32 pages);
61e021f3 250
c9da161c 251struct bpf_map *bpf_map_get_with_uref(u32 ufd);
c2101297 252struct bpf_map *__bpf_map_get(struct fd f);
6d67942d 253struct bpf_map * __must_check bpf_map_inc(struct bpf_map *map, bool uref);
c9da161c 254void bpf_map_put_with_uref(struct bpf_map *map);
61e021f3 255void bpf_map_put(struct bpf_map *map);
6c905981 256int bpf_map_precharge_memlock(u32 pages);
d407bd25
DB
257void *bpf_map_area_alloc(size_t size);
258void bpf_map_area_free(void *base);
61e021f3 259
1be7f75d
AS
260extern int sysctl_unprivileged_bpf_disabled;
261
b2197755
DB
262int bpf_map_new_fd(struct bpf_map *map);
263int bpf_prog_new_fd(struct bpf_prog *prog);
264
265int bpf_obj_pin_user(u32 ufd, const char __user *pathname);
266int bpf_obj_get_user(const char __user *pathname);
267
15a07b33
AS
268int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value);
269int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value);
270int bpf_percpu_hash_update(struct bpf_map *map, void *key, void *value,
271 u64 flags);
272int bpf_percpu_array_update(struct bpf_map *map, void *key, void *value,
273 u64 flags);
d056a788 274
557c0c6e 275int bpf_stackmap_copy(struct bpf_map *map, void *key, void *value);
15a07b33 276
d056a788
DB
277int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file,
278 void *key, void *value, u64 map_flags);
279void bpf_fd_array_map_clear(struct bpf_map *map);
bcc6b1b7
MKL
280int bpf_fd_htab_map_update_elem(struct bpf_map *map, struct file *map_file,
281 void *key, void *value, u64 map_flags);
d056a788 282
15a07b33
AS
283/* memcpy that is used with 8-byte aligned pointers, power-of-8 size and
284 * forced to use 'long' read/writes to try to atomically copy long counters.
285 * Best-effort only. No barriers here, since it _will_ race with concurrent
286 * updates from BPF programs. Called from bpf syscall and mostly used with
287 * size 8 or 16 bytes, so ask compiler to inline it.
288 */
289static inline void bpf_long_memcpy(void *dst, const void *src, u32 size)
290{
291 const long *lsrc = src;
292 long *ldst = dst;
293
294 size /= sizeof(long);
295 while (size--)
296 *ldst++ = *lsrc++;
297}
298
61e021f3 299/* verify correctness of eBPF program */
9bac3d6d 300int bpf_check(struct bpf_prog **fp, union bpf_attr *attr);
89aa0758 301#else
0fc174de
DB
302static inline struct bpf_prog *bpf_prog_get(u32 ufd)
303{
304 return ERR_PTR(-EOPNOTSUPP);
305}
306
113214be
DB
307static inline struct bpf_prog *bpf_prog_get_type(u32 ufd,
308 enum bpf_prog_type type)
309{
310 return ERR_PTR(-EOPNOTSUPP);
311}
6d67942d
DB
312static inline struct bpf_prog * __must_check bpf_prog_add(struct bpf_prog *prog,
313 int i)
cc2e0b3f
BB
314{
315 return ERR_PTR(-EOPNOTSUPP);
316}
113214be 317
c540594f
DB
318static inline void bpf_prog_sub(struct bpf_prog *prog, int i)
319{
320}
321
0fc174de
DB
322static inline void bpf_prog_put(struct bpf_prog *prog)
323{
324}
6d67942d
DB
325
326static inline struct bpf_prog * __must_check bpf_prog_inc(struct bpf_prog *prog)
aa6a5f3c
AS
327{
328 return ERR_PTR(-EOPNOTSUPP);
329}
5ccb071e
DB
330
331static inline int __bpf_prog_charge(struct user_struct *user, u32 pages)
332{
333 return 0;
334}
335
336static inline void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
337{
338}
61e021f3 339#endif /* CONFIG_BPF_SYSCALL */
09756af4 340
d0003ec0 341/* verifier prototypes for helper functions called from eBPF programs */
a2c83fff
DB
342extern const struct bpf_func_proto bpf_map_lookup_elem_proto;
343extern const struct bpf_func_proto bpf_map_update_elem_proto;
344extern const struct bpf_func_proto bpf_map_delete_elem_proto;
d0003ec0 345
03e69b50 346extern const struct bpf_func_proto bpf_get_prandom_u32_proto;
c04167ce 347extern const struct bpf_func_proto bpf_get_smp_processor_id_proto;
2d0e30c3 348extern const struct bpf_func_proto bpf_get_numa_node_id_proto;
04fd61ab 349extern const struct bpf_func_proto bpf_tail_call_proto;
17ca8cbf 350extern const struct bpf_func_proto bpf_ktime_get_ns_proto;
ffeedafb
AS
351extern const struct bpf_func_proto bpf_get_current_pid_tgid_proto;
352extern const struct bpf_func_proto bpf_get_current_uid_gid_proto;
353extern const struct bpf_func_proto bpf_get_current_comm_proto;
4e10df9a
AS
354extern const struct bpf_func_proto bpf_skb_vlan_push_proto;
355extern const struct bpf_func_proto bpf_skb_vlan_pop_proto;
d5a3b1f6 356extern const struct bpf_func_proto bpf_get_stackid_proto;
03e69b50 357
3ad00405
DB
358/* Shared helpers among cBPF and eBPF. */
359void bpf_user_rnd_init_once(void);
360u64 bpf_user_rnd_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
361
99c55f7d 362#endif /* _LINUX_BPF_H */