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>
12 #include <linux/workqueue.h>
13 #include <linux/file.h>
14 #include <linux/percpu.h>
15 #include <linux/err.h>
16 #include <linux/rbtree_latch.h>
17 #include <linux/numa.h>
23 /* map is generic key/value storage optionally accesible by eBPF programs */
25 /* funcs callable from userspace (via syscall) */
26 struct bpf_map *(*map_alloc)(union bpf_attr *attr);
27 void (*map_release)(struct bpf_map *map, struct file *map_file);
28 void (*map_free)(struct bpf_map *map);
29 int (*map_get_next_key)(struct bpf_map *map, void *key, void *next_key);
31 /* funcs callable from userspace and from eBPF programs */
32 void *(*map_lookup_elem)(struct bpf_map *map, void *key);
33 int (*map_update_elem)(struct bpf_map *map, void *key, void *value, u64 flags);
34 int (*map_delete_elem)(struct bpf_map *map, void *key);
36 /* funcs called by prog_array and perf_event_array map */
37 void *(*map_fd_get_ptr)(struct bpf_map *map, struct file *map_file,
39 void (*map_fd_put_ptr)(void *ptr);
40 u32 (*map_gen_lookup)(struct bpf_map *map, struct bpf_insn *insn_buf);
41 u32 (*map_fd_sys_lookup_elem)(void *ptr);
46 enum bpf_map_type map_type;
54 struct user_struct *user;
55 const struct bpf_map_ops *ops;
56 struct work_struct work;
58 struct bpf_map *inner_map_meta;
61 /* function argument constraints */
63 ARG_DONTCARE = 0, /* unused argument in helper function */
65 /* the following constraints used to prototype
66 * bpf_map_lookup/update/delete_elem() functions
68 ARG_CONST_MAP_PTR, /* const argument used as pointer to bpf_map */
69 ARG_PTR_TO_MAP_KEY, /* pointer to stack used as map key */
70 ARG_PTR_TO_MAP_VALUE, /* pointer to stack used as map value */
72 /* the following constraints used to prototype bpf_memcmp() and other
73 * functions that access data on eBPF program stack
75 ARG_PTR_TO_MEM, /* pointer to valid memory (stack, packet, map value) */
76 ARG_PTR_TO_UNINIT_MEM, /* pointer to memory does not need to be initialized,
77 * helper function must fill all bytes or clear
81 ARG_CONST_SIZE, /* number of bytes accessed from memory */
82 ARG_CONST_SIZE_OR_ZERO, /* number of bytes accessed from memory or 0 */
84 ARG_PTR_TO_CTX, /* pointer to context */
85 ARG_ANYTHING, /* any (initialized) argument is ok */
88 /* type of values returned from helper functions */
89 enum bpf_return_type {
90 RET_INTEGER, /* function returns integer */
91 RET_VOID, /* function doesn't return anything */
92 RET_PTR_TO_MAP_VALUE_OR_NULL, /* returns a pointer to map elem value or NULL */
95 /* eBPF function prototype used by verifier to allow BPF_CALLs from eBPF programs
96 * to in-kernel helper functions and for adjusting imm32 field in BPF_CALL
97 * instructions after verifying
99 struct bpf_func_proto {
100 u64 (*func)(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
103 enum bpf_return_type ret_type;
104 enum bpf_arg_type arg1_type;
105 enum bpf_arg_type arg2_type;
106 enum bpf_arg_type arg3_type;
107 enum bpf_arg_type arg4_type;
108 enum bpf_arg_type arg5_type;
111 /* bpf_context is intentionally undefined structure. Pointer to bpf_context is
112 * the first argument to eBPF programs.
113 * For socket filters: 'struct bpf_context *' == 'struct sk_buff *'
117 enum bpf_access_type {
122 /* types of values stored in eBPF registers */
123 /* Pointer types represent:
126 * pointer + (u16) var
127 * pointer + (u16) var + imm
128 * if (range > 0) then [ptr, ptr + range - off) is safe to access
129 * if (id > 0) means that some 'var' was added
130 * if (off > 0) means that 'imm' was added
133 NOT_INIT = 0, /* nothing was written into register */
134 SCALAR_VALUE, /* reg doesn't contain a valid pointer */
135 PTR_TO_CTX, /* reg points to bpf_context */
136 CONST_PTR_TO_MAP, /* reg points to struct bpf_map */
137 PTR_TO_MAP_VALUE, /* reg points to map element value */
138 PTR_TO_MAP_VALUE_OR_NULL,/* points to map elem value or NULL */
139 PTR_TO_STACK, /* reg == frame_pointer + offset */
140 PTR_TO_PACKET_META, /* skb->data - meta_len */
141 PTR_TO_PACKET, /* reg points to skb->data */
142 PTR_TO_PACKET_END, /* skb->data + headlen */
145 /* The information passed from prog-specific *_is_valid_access
146 * back to the verifier.
148 struct bpf_insn_access_aux {
149 enum bpf_reg_type reg_type;
154 bpf_ctx_record_field_size(struct bpf_insn_access_aux *aux, u32 size)
156 aux->ctx_field_size = size;
159 struct bpf_verifier_ops {
160 /* return eBPF function prototype for verification */
161 const struct bpf_func_proto *(*get_func_proto)(enum bpf_func_id func_id);
163 /* return true if 'size' wide access at offset 'off' within bpf_context
164 * with 'type' (read or write) is allowed
166 bool (*is_valid_access)(int off, int size, enum bpf_access_type type,
167 struct bpf_insn_access_aux *info);
168 int (*gen_prologue)(struct bpf_insn *insn, bool direct_write,
169 const struct bpf_prog *prog);
170 u32 (*convert_ctx_access)(enum bpf_access_type type,
171 const struct bpf_insn *src,
172 struct bpf_insn *dst,
173 struct bpf_prog *prog, u32 *target_size);
174 int (*test_run)(struct bpf_prog *prog, const union bpf_attr *kattr,
175 union bpf_attr __user *uattr);
178 struct bpf_prog_aux {
184 struct latch_tree_node ksym_tnode;
185 struct list_head ksym_lnode;
186 const struct bpf_verifier_ops *ops;
187 struct bpf_map **used_maps;
188 struct bpf_prog *prog;
189 struct user_struct *user;
191 struct work_struct work;
199 /* 'ownership' of prog_array is claimed by the first program that
200 * is going to use this map or by the first program which FD is stored
201 * in the map to make sure that all callers and callees have the same
202 * prog_type and JITed flag
204 enum bpf_prog_type owner_prog_type;
207 char value[0] __aligned(8);
208 void *ptrs[0] __aligned(8);
209 void __percpu *pptrs[0] __aligned(8);
213 #define MAX_TAIL_CALL_CNT 32
215 struct bpf_event_entry {
216 struct perf_event *event;
217 struct file *perf_file;
218 struct file *map_file;
222 u64 bpf_tail_call(u64 ctx, u64 r2, u64 index, u64 r4, u64 r5);
223 u64 bpf_get_stackid(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
225 bool bpf_prog_array_compatible(struct bpf_array *array, const struct bpf_prog *fp);
226 int bpf_prog_calc_tag(struct bpf_prog *fp);
228 const struct bpf_func_proto *bpf_get_trace_printk_proto(void);
230 typedef unsigned long (*bpf_ctx_copy_t)(void *dst, const void *src,
231 unsigned long off, unsigned long len);
233 u64 bpf_event_output(struct bpf_map *map, u64 flags, void *meta, u64 meta_size,
234 void *ctx, u64 ctx_size, bpf_ctx_copy_t ctx_copy);
236 int bpf_prog_test_run_xdp(struct bpf_prog *prog, const union bpf_attr *kattr,
237 union bpf_attr __user *uattr);
238 int bpf_prog_test_run_skb(struct bpf_prog *prog, const union bpf_attr *kattr,
239 union bpf_attr __user *uattr);
241 #ifdef CONFIG_BPF_SYSCALL
242 DECLARE_PER_CPU(int, bpf_prog_active);
244 #define BPF_PROG_TYPE(_id, _ops) \
245 extern const struct bpf_verifier_ops _ops;
246 #define BPF_MAP_TYPE(_id, _ops) \
247 extern const struct bpf_map_ops _ops;
248 #include <linux/bpf_types.h>
252 struct bpf_prog *bpf_prog_get(u32 ufd);
253 struct bpf_prog *bpf_prog_get_type(u32 ufd, enum bpf_prog_type type);
254 struct bpf_prog * __must_check bpf_prog_add(struct bpf_prog *prog, int i);
255 void bpf_prog_sub(struct bpf_prog *prog, int i);
256 struct bpf_prog * __must_check bpf_prog_inc(struct bpf_prog *prog);
257 struct bpf_prog * __must_check bpf_prog_inc_not_zero(struct bpf_prog *prog);
258 void bpf_prog_put(struct bpf_prog *prog);
259 int __bpf_prog_charge(struct user_struct *user, u32 pages);
260 void __bpf_prog_uncharge(struct user_struct *user, u32 pages);
262 struct bpf_map *bpf_map_get_with_uref(u32 ufd);
263 struct bpf_map *__bpf_map_get(struct fd f);
264 struct bpf_map * __must_check bpf_map_inc(struct bpf_map *map, bool uref);
265 void bpf_map_put_with_uref(struct bpf_map *map);
266 void bpf_map_put(struct bpf_map *map);
267 int bpf_map_precharge_memlock(u32 pages);
268 void *bpf_map_area_alloc(size_t size, int numa_node);
269 void bpf_map_area_free(void *base);
271 extern int sysctl_unprivileged_bpf_disabled;
273 int bpf_map_new_fd(struct bpf_map *map);
274 int bpf_prog_new_fd(struct bpf_prog *prog);
276 int bpf_obj_pin_user(u32 ufd, const char __user *pathname);
277 int bpf_obj_get_user(const char __user *pathname);
279 int bpf_percpu_hash_copy(struct bpf_map *map, void *key, void *value);
280 int bpf_percpu_array_copy(struct bpf_map *map, void *key, void *value);
281 int bpf_percpu_hash_update(struct bpf_map *map, void *key, void *value,
283 int bpf_percpu_array_update(struct bpf_map *map, void *key, void *value,
286 int bpf_stackmap_copy(struct bpf_map *map, void *key, void *value);
288 int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file,
289 void *key, void *value, u64 map_flags);
290 int bpf_fd_array_map_lookup_elem(struct bpf_map *map, void *key, u32 *value);
291 void bpf_fd_array_map_clear(struct bpf_map *map);
292 int bpf_fd_htab_map_update_elem(struct bpf_map *map, struct file *map_file,
293 void *key, void *value, u64 map_flags);
294 int bpf_fd_htab_map_lookup_elem(struct bpf_map *map, void *key, u32 *value);
296 /* memcpy that is used with 8-byte aligned pointers, power-of-8 size and
297 * forced to use 'long' read/writes to try to atomically copy long counters.
298 * Best-effort only. No barriers here, since it _will_ race with concurrent
299 * updates from BPF programs. Called from bpf syscall and mostly used with
300 * size 8 or 16 bytes, so ask compiler to inline it.
302 static inline void bpf_long_memcpy(void *dst, const void *src, u32 size)
304 const long *lsrc = src;
307 size /= sizeof(long);
312 /* verify correctness of eBPF program */
313 int bpf_check(struct bpf_prog **fp, union bpf_attr *attr);
316 struct net_device *__dev_map_lookup_elem(struct bpf_map *map, u32 key);
317 void __dev_map_insert_ctx(struct bpf_map *map, u32 index);
318 void __dev_map_flush(struct bpf_map *map);
320 /* Return map's numa specified by userspace */
321 static inline int bpf_map_attr_numa_node(const union bpf_attr *attr)
323 return (attr->map_flags & BPF_F_NUMA_NODE) ?
324 attr->numa_node : NUMA_NO_NODE;
328 static inline struct bpf_prog *bpf_prog_get(u32 ufd)
330 return ERR_PTR(-EOPNOTSUPP);
333 static inline struct bpf_prog *bpf_prog_get_type(u32 ufd,
334 enum bpf_prog_type type)
336 return ERR_PTR(-EOPNOTSUPP);
338 static inline struct bpf_prog * __must_check bpf_prog_add(struct bpf_prog *prog,
341 return ERR_PTR(-EOPNOTSUPP);
344 static inline void bpf_prog_sub(struct bpf_prog *prog, int i)
348 static inline void bpf_prog_put(struct bpf_prog *prog)
352 static inline struct bpf_prog * __must_check bpf_prog_inc(struct bpf_prog *prog)
354 return ERR_PTR(-EOPNOTSUPP);
357 static inline struct bpf_prog *__must_check
358 bpf_prog_inc_not_zero(struct bpf_prog *prog)
360 return ERR_PTR(-EOPNOTSUPP);
363 static inline int __bpf_prog_charge(struct user_struct *user, u32 pages)
368 static inline void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
372 static inline struct net_device *__dev_map_lookup_elem(struct bpf_map *map,
378 static inline void __dev_map_insert_ctx(struct bpf_map *map, u32 index)
382 static inline void __dev_map_flush(struct bpf_map *map)
385 #endif /* CONFIG_BPF_SYSCALL */
387 #if defined(CONFIG_STREAM_PARSER) && defined(CONFIG_BPF_SYSCALL)
388 struct sock *__sock_map_lookup_elem(struct bpf_map *map, u32 key);
389 int sock_map_prog(struct bpf_map *map, struct bpf_prog *prog, u32 type);
391 static inline struct sock *__sock_map_lookup_elem(struct bpf_map *map, u32 key)
396 static inline int sock_map_prog(struct bpf_map *map,
397 struct bpf_prog *prog,
404 /* verifier prototypes for helper functions called from eBPF programs */
405 extern const struct bpf_func_proto bpf_map_lookup_elem_proto;
406 extern const struct bpf_func_proto bpf_map_update_elem_proto;
407 extern const struct bpf_func_proto bpf_map_delete_elem_proto;
409 extern const struct bpf_func_proto bpf_get_prandom_u32_proto;
410 extern const struct bpf_func_proto bpf_get_smp_processor_id_proto;
411 extern const struct bpf_func_proto bpf_get_numa_node_id_proto;
412 extern const struct bpf_func_proto bpf_tail_call_proto;
413 extern const struct bpf_func_proto bpf_ktime_get_ns_proto;
414 extern const struct bpf_func_proto bpf_get_current_pid_tgid_proto;
415 extern const struct bpf_func_proto bpf_get_current_uid_gid_proto;
416 extern const struct bpf_func_proto bpf_get_current_comm_proto;
417 extern const struct bpf_func_proto bpf_skb_vlan_push_proto;
418 extern const struct bpf_func_proto bpf_skb_vlan_pop_proto;
419 extern const struct bpf_func_proto bpf_get_stackid_proto;
420 extern const struct bpf_func_proto bpf_sock_map_update_proto;
422 /* Shared helpers among cBPF and eBPF. */
423 void bpf_user_rnd_init_once(void);
424 u64 bpf_user_rnd_u32(u64 r1, u64 r2, u64 r3, u64 r4, u64 r5);
426 #endif /* _LINUX_BPF_H */