1 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
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.
10 #include <uapi/linux/bpf.h>
11 #include <linux/workqueue.h>
12 #include <linux/file.h>
13 #include <linux/percpu.h>
14 #include <linux/err.h>
18 /* map is generic key/value storage optionally accesible by eBPF programs */
20 /* funcs callable from userspace (via syscall) */
21 struct bpf_map
*(*map_alloc
)(union bpf_attr
*attr
);
22 void (*map_free
)(struct bpf_map
*);
23 int (*map_get_next_key
)(struct bpf_map
*map
, void *key
, void *next_key
);
25 /* funcs callable from userspace and from eBPF programs */
26 void *(*map_lookup_elem
)(struct bpf_map
*map
, void *key
);
27 int (*map_update_elem
)(struct bpf_map
*map
, void *key
, void *value
, u64 flags
);
28 int (*map_delete_elem
)(struct bpf_map
*map
, void *key
);
30 /* funcs called by prog_array and perf_event_array map */
31 void *(*map_fd_get_ptr
) (struct bpf_map
*map
, int fd
);
32 void (*map_fd_put_ptr
) (void *ptr
);
37 enum bpf_map_type map_type
;
43 struct user_struct
*user
;
44 const struct bpf_map_ops
*ops
;
45 struct work_struct work
;
49 struct bpf_map_type_list
{
50 struct list_head list_node
;
51 const struct bpf_map_ops
*ops
;
52 enum bpf_map_type type
;
55 /* function argument constraints */
57 ARG_DONTCARE
= 0, /* unused argument in helper function */
59 /* the following constraints used to prototype
60 * bpf_map_lookup/update/delete_elem() functions
62 ARG_CONST_MAP_PTR
, /* const argument used as pointer to bpf_map */
63 ARG_PTR_TO_MAP_KEY
, /* pointer to stack used as map key */
64 ARG_PTR_TO_MAP_VALUE
, /* pointer to stack used as map value */
66 /* the following constraints used to prototype bpf_memcmp() and other
67 * functions that access data on eBPF program stack
69 ARG_PTR_TO_STACK
, /* any pointer to eBPF program stack */
70 ARG_PTR_TO_RAW_STACK
, /* any pointer to eBPF program stack, area does not
71 * need to be initialized, helper function must fill
72 * all bytes or clear them in error case.
75 ARG_CONST_STACK_SIZE
, /* number of bytes accessed from stack */
76 ARG_CONST_STACK_SIZE_OR_ZERO
, /* number of bytes accessed from stack or 0 */
78 ARG_PTR_TO_CTX
, /* pointer to context */
79 ARG_ANYTHING
, /* any (initialized) argument is ok */
82 /* type of values returned from helper functions */
83 enum bpf_return_type
{
84 RET_INTEGER
, /* function returns integer */
85 RET_VOID
, /* function doesn't return anything */
86 RET_PTR_TO_MAP_VALUE_OR_NULL
, /* returns a pointer to map elem value or NULL */
89 /* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
90 * to in-kernel helper functions and for adjusting imm32 field in BPF_CALL
91 * instructions after verifying
93 struct bpf_func_proto
{
94 u64 (*func
)(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
);
96 enum bpf_return_type ret_type
;
97 enum bpf_arg_type arg1_type
;
98 enum bpf_arg_type arg2_type
;
99 enum bpf_arg_type arg3_type
;
100 enum bpf_arg_type arg4_type
;
101 enum bpf_arg_type arg5_type
;
104 /* bpf_context is intentionally undefined structure. Pointer to bpf_context is
105 * the first argument to eBPF programs.
106 * For socket filters: 'struct bpf_context *' == 'struct sk_buff *'
110 enum bpf_access_type
{
117 struct bpf_verifier_ops
{
118 /* return eBPF function prototype for verification */
119 const struct bpf_func_proto
*(*get_func_proto
)(enum bpf_func_id func_id
);
121 /* return true if 'size' wide access at offset 'off' within bpf_context
122 * with 'type' (read or write) is allowed
124 bool (*is_valid_access
)(int off
, int size
, enum bpf_access_type type
);
126 u32 (*convert_ctx_access
)(enum bpf_access_type type
, int dst_reg
,
127 int src_reg
, int ctx_off
,
128 struct bpf_insn
*insn
, struct bpf_prog
*prog
);
131 struct bpf_prog_type_list
{
132 struct list_head list_node
;
133 const struct bpf_verifier_ops
*ops
;
134 enum bpf_prog_type type
;
137 struct bpf_prog_aux
{
141 const struct bpf_verifier_ops
*ops
;
142 struct bpf_map
**used_maps
;
143 struct bpf_prog
*prog
;
144 struct user_struct
*user
;
146 struct work_struct work
;
154 /* 'ownership' of prog_array is claimed by the first program that
155 * is going to use this map or by the first program which FD is stored
156 * in the map to make sure that all callers and callees have the same
157 * prog_type and JITed flag
159 enum bpf_prog_type owner_prog_type
;
162 char value
[0] __aligned(8);
163 void *ptrs
[0] __aligned(8);
164 void __percpu
*pptrs
[0] __aligned(8);
167 #define MAX_TAIL_CALL_CNT 32
169 u64
bpf_tail_call(u64 ctx
, u64 r2
, u64 index
, u64 r4
, u64 r5
);
170 u64
bpf_get_stackid(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
);
171 void bpf_fd_array_map_clear(struct bpf_map
*map
);
172 bool bpf_prog_array_compatible(struct bpf_array
*array
, const struct bpf_prog
*fp
);
174 const struct bpf_func_proto
*bpf_get_trace_printk_proto(void);
175 const struct bpf_func_proto
*bpf_get_event_output_proto(void);
177 #ifdef CONFIG_BPF_SYSCALL
178 DECLARE_PER_CPU(int, bpf_prog_active
);
180 void bpf_register_prog_type(struct bpf_prog_type_list
*tl
);
181 void bpf_register_map_type(struct bpf_map_type_list
*tl
);
183 struct bpf_prog
*bpf_prog_get(u32 ufd
);
184 struct bpf_prog
*bpf_prog_inc(struct bpf_prog
*prog
);
185 void bpf_prog_put(struct bpf_prog
*prog
);
186 void bpf_prog_put_rcu(struct bpf_prog
*prog
);
188 struct bpf_map
*bpf_map_get_with_uref(u32 ufd
);
189 struct bpf_map
*__bpf_map_get(struct fd f
);
190 struct bpf_map
*bpf_map_inc(struct bpf_map
*map
, bool uref
);
191 void bpf_map_put_with_uref(struct bpf_map
*map
);
192 void bpf_map_put(struct bpf_map
*map
);
193 int bpf_map_precharge_memlock(u32 pages
);
195 extern int sysctl_unprivileged_bpf_disabled
;
197 int bpf_map_new_fd(struct bpf_map
*map
);
198 int bpf_prog_new_fd(struct bpf_prog
*prog
);
200 int bpf_obj_pin_user(u32 ufd
, const char __user
*pathname
);
201 int bpf_obj_get_user(const char __user
*pathname
);
203 int bpf_percpu_hash_copy(struct bpf_map
*map
, void *key
, void *value
);
204 int bpf_percpu_array_copy(struct bpf_map
*map
, void *key
, void *value
);
205 int bpf_percpu_hash_update(struct bpf_map
*map
, void *key
, void *value
,
207 int bpf_percpu_array_update(struct bpf_map
*map
, void *key
, void *value
,
209 int bpf_stackmap_copy(struct bpf_map
*map
, void *key
, void *value
);
211 /* memcpy that is used with 8-byte aligned pointers, power-of-8 size and
212 * forced to use 'long' read/writes to try to atomically copy long counters.
213 * Best-effort only. No barriers here, since it _will_ race with concurrent
214 * updates from BPF programs. Called from bpf syscall and mostly used with
215 * size 8 or 16 bytes, so ask compiler to inline it.
217 static inline void bpf_long_memcpy(void *dst
, const void *src
, u32 size
)
219 const long *lsrc
= src
;
222 size
/= sizeof(long);
227 /* verify correctness of eBPF program */
228 int bpf_check(struct bpf_prog
**fp
, union bpf_attr
*attr
);
230 static inline void bpf_register_prog_type(struct bpf_prog_type_list
*tl
)
234 static inline struct bpf_prog
*bpf_prog_get(u32 ufd
)
236 return ERR_PTR(-EOPNOTSUPP
);
239 static inline void bpf_prog_put(struct bpf_prog
*prog
)
242 #endif /* CONFIG_BPF_SYSCALL */
244 /* verifier prototypes for helper functions called from eBPF programs */
245 extern const struct bpf_func_proto bpf_map_lookup_elem_proto
;
246 extern const struct bpf_func_proto bpf_map_update_elem_proto
;
247 extern const struct bpf_func_proto bpf_map_delete_elem_proto
;
249 extern const struct bpf_func_proto bpf_get_prandom_u32_proto
;
250 extern const struct bpf_func_proto bpf_get_smp_processor_id_proto
;
251 extern const struct bpf_func_proto bpf_tail_call_proto
;
252 extern const struct bpf_func_proto bpf_ktime_get_ns_proto
;
253 extern const struct bpf_func_proto bpf_get_current_pid_tgid_proto
;
254 extern const struct bpf_func_proto bpf_get_current_uid_gid_proto
;
255 extern const struct bpf_func_proto bpf_get_current_comm_proto
;
256 extern const struct bpf_func_proto bpf_skb_vlan_push_proto
;
257 extern const struct bpf_func_proto bpf_skb_vlan_pop_proto
;
258 extern const struct bpf_func_proto bpf_get_stackid_proto
;
260 /* Shared helpers among cBPF and eBPF. */
261 void bpf_user_rnd_init_once(void);
262 u64
bpf_user_rnd_u32(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
);
264 #endif /* _LINUX_BPF_H */