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>
16 /* map is generic key/value storage optionally accesible by eBPF programs */
18 /* funcs callable from userspace (via syscall) */
19 struct bpf_map
*(*map_alloc
)(union bpf_attr
*attr
);
20 void (*map_free
)(struct bpf_map
*);
21 int (*map_get_next_key
)(struct bpf_map
*map
, void *key
, void *next_key
);
23 /* funcs callable from userspace and from eBPF programs */
24 void *(*map_lookup_elem
)(struct bpf_map
*map
, void *key
);
25 int (*map_update_elem
)(struct bpf_map
*map
, void *key
, void *value
, u64 flags
);
26 int (*map_delete_elem
)(struct bpf_map
*map
, void *key
);
28 /* funcs called by prog_array and perf_event_array map */
29 void *(*map_fd_get_ptr
) (struct bpf_map
*map
, int fd
);
30 void (*map_fd_put_ptr
) (void *ptr
);
35 enum bpf_map_type map_type
;
40 struct user_struct
*user
;
41 const struct bpf_map_ops
*ops
;
42 struct work_struct work
;
45 struct bpf_map_type_list
{
46 struct list_head list_node
;
47 const struct bpf_map_ops
*ops
;
48 enum bpf_map_type type
;
51 /* function argument constraints */
53 ARG_DONTCARE
= 0, /* unused argument in helper function */
55 /* the following constraints used to prototype
56 * bpf_map_lookup/update/delete_elem() functions
58 ARG_CONST_MAP_PTR
, /* const argument used as pointer to bpf_map */
59 ARG_PTR_TO_MAP_KEY
, /* pointer to stack used as map key */
60 ARG_PTR_TO_MAP_VALUE
, /* pointer to stack used as map value */
62 /* the following constraints used to prototype bpf_memcmp() and other
63 * functions that access data on eBPF program stack
65 ARG_PTR_TO_STACK
, /* any pointer to eBPF program stack */
66 ARG_CONST_STACK_SIZE
, /* number of bytes accessed from stack */
68 ARG_PTR_TO_CTX
, /* pointer to context */
69 ARG_ANYTHING
, /* any (initialized) argument is ok */
72 /* type of values returned from helper functions */
73 enum bpf_return_type
{
74 RET_INTEGER
, /* function returns integer */
75 RET_VOID
, /* function doesn't return anything */
76 RET_PTR_TO_MAP_VALUE_OR_NULL
, /* returns a pointer to map elem value or NULL */
79 /* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
80 * to in-kernel helper functions and for adjusting imm32 field in BPF_CALL
81 * instructions after verifying
83 struct bpf_func_proto
{
84 u64 (*func
)(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
);
86 enum bpf_return_type ret_type
;
87 enum bpf_arg_type arg1_type
;
88 enum bpf_arg_type arg2_type
;
89 enum bpf_arg_type arg3_type
;
90 enum bpf_arg_type arg4_type
;
91 enum bpf_arg_type arg5_type
;
94 /* bpf_context is intentionally undefined structure. Pointer to bpf_context is
95 * the first argument to eBPF programs.
96 * For socket filters: 'struct bpf_context *' == 'struct sk_buff *'
100 enum bpf_access_type
{
107 struct bpf_verifier_ops
{
108 /* return eBPF function prototype for verification */
109 const struct bpf_func_proto
*(*get_func_proto
)(enum bpf_func_id func_id
);
111 /* return true if 'size' wide access at offset 'off' within bpf_context
112 * with 'type' (read or write) is allowed
114 bool (*is_valid_access
)(int off
, int size
, enum bpf_access_type type
);
116 u32 (*convert_ctx_access
)(enum bpf_access_type type
, int dst_reg
,
117 int src_reg
, int ctx_off
,
118 struct bpf_insn
*insn
, struct bpf_prog
*prog
);
121 struct bpf_prog_type_list
{
122 struct list_head list_node
;
123 const struct bpf_verifier_ops
*ops
;
124 enum bpf_prog_type type
;
127 struct bpf_prog_aux
{
130 const struct bpf_verifier_ops
*ops
;
131 struct bpf_map
**used_maps
;
132 struct bpf_prog
*prog
;
133 struct user_struct
*user
;
135 struct work_struct work
;
143 /* 'ownership' of prog_array is claimed by the first program that
144 * is going to use this map or by the first program which FD is stored
145 * in the map to make sure that all callers and callees have the same
146 * prog_type and JITed flag
148 enum bpf_prog_type owner_prog_type
;
151 char value
[0] __aligned(8);
152 void *ptrs
[0] __aligned(8);
155 #define MAX_TAIL_CALL_CNT 32
157 u64
bpf_tail_call(u64 ctx
, u64 r2
, u64 index
, u64 r4
, u64 r5
);
158 void bpf_fd_array_map_clear(struct bpf_map
*map
);
159 bool bpf_prog_array_compatible(struct bpf_array
*array
, const struct bpf_prog
*fp
);
160 const struct bpf_func_proto
*bpf_get_trace_printk_proto(void);
162 #ifdef CONFIG_BPF_SYSCALL
163 void bpf_register_prog_type(struct bpf_prog_type_list
*tl
);
164 void bpf_register_map_type(struct bpf_map_type_list
*tl
);
166 struct bpf_prog
*bpf_prog_get(u32 ufd
);
167 void bpf_prog_put(struct bpf_prog
*prog
);
168 void bpf_prog_put_rcu(struct bpf_prog
*prog
);
170 struct bpf_map
*bpf_map_get(u32 ufd
);
171 struct bpf_map
*__bpf_map_get(struct fd f
);
172 void bpf_map_put(struct bpf_map
*map
);
174 extern int sysctl_unprivileged_bpf_disabled
;
176 int bpf_map_new_fd(struct bpf_map
*map
);
177 int bpf_prog_new_fd(struct bpf_prog
*prog
);
179 int bpf_obj_pin_user(u32 ufd
, const char __user
*pathname
);
180 int bpf_obj_get_user(const char __user
*pathname
);
182 /* verify correctness of eBPF program */
183 int bpf_check(struct bpf_prog
**fp
, union bpf_attr
*attr
);
185 static inline void bpf_register_prog_type(struct bpf_prog_type_list
*tl
)
189 static inline struct bpf_prog
*bpf_prog_get(u32 ufd
)
191 return ERR_PTR(-EOPNOTSUPP
);
194 static inline void bpf_prog_put(struct bpf_prog
*prog
)
197 #endif /* CONFIG_BPF_SYSCALL */
199 /* verifier prototypes for helper functions called from eBPF programs */
200 extern const struct bpf_func_proto bpf_map_lookup_elem_proto
;
201 extern const struct bpf_func_proto bpf_map_update_elem_proto
;
202 extern const struct bpf_func_proto bpf_map_delete_elem_proto
;
204 extern const struct bpf_func_proto bpf_get_prandom_u32_proto
;
205 extern const struct bpf_func_proto bpf_get_smp_processor_id_proto
;
206 extern const struct bpf_func_proto bpf_tail_call_proto
;
207 extern const struct bpf_func_proto bpf_ktime_get_ns_proto
;
208 extern const struct bpf_func_proto bpf_get_current_pid_tgid_proto
;
209 extern const struct bpf_func_proto bpf_get_current_uid_gid_proto
;
210 extern const struct bpf_func_proto bpf_get_current_comm_proto
;
211 extern const struct bpf_func_proto bpf_skb_vlan_push_proto
;
212 extern const struct bpf_func_proto bpf_skb_vlan_pop_proto
;
214 /* Shared helpers among cBPF and eBPF. */
215 void bpf_user_rnd_init_once(void);
216 u64
bpf_user_rnd_u32(u64 r1
, u64 r2
, u64 r3
, u64 r4
, u64 r5
);
218 #endif /* _LINUX_BPF_H */