1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
2 
3 /*
4  * Common eBPF ELF object loading operations.
5  *
6  * Copyright (C) 2013-2015 Alexei Starovoitov <ast@kernel.org>
7  * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com>
8  * Copyright (C) 2015 Huawei Inc.
9  */
10 #ifndef __LIBBPF_LIBBPF_H
11 #define __LIBBPF_LIBBPF_H
12 
13 #include <stdarg.h>
14 #include <stdio.h>
15 #include <stdint.h>
16 #include <stdbool.h>
17 #include <sys/types.h>  // for size_t
18 #include <linux/bpf.h>
19 
20 #include "libbpf_common.h"
21 #include "libbpf_legacy.h"
22 
23 #ifdef __cplusplus
24 extern "C" {
25 #endif
26 
27 LIBBPF_API __u32 libbpf_major_version(void);
28 LIBBPF_API __u32 libbpf_minor_version(void);
29 LIBBPF_API const char *libbpf_version_string(void);
30 
31 enum libbpf_errno {
32 	__LIBBPF_ERRNO__START = 4000,
33 
34 	/* Something wrong in libelf */
35 	LIBBPF_ERRNO__LIBELF = __LIBBPF_ERRNO__START,
36 	LIBBPF_ERRNO__FORMAT,	/* BPF object format invalid */
37 	LIBBPF_ERRNO__KVERSION,	/* Incorrect or no 'version' section */
38 	LIBBPF_ERRNO__ENDIAN,	/* Endian mismatch */
39 	LIBBPF_ERRNO__INTERNAL,	/* Internal error in libbpf */
40 	LIBBPF_ERRNO__RELOC,	/* Relocation failed */
41 	LIBBPF_ERRNO__LOAD,	/* Load program failure for unknown reason */
42 	LIBBPF_ERRNO__VERIFY,	/* Kernel verifier blocks program loading */
43 	LIBBPF_ERRNO__PROG2BIG,	/* Program too big */
44 	LIBBPF_ERRNO__KVER,	/* Incorrect kernel version */
45 	LIBBPF_ERRNO__PROGTYPE,	/* Kernel doesn't support this program type */
46 	LIBBPF_ERRNO__WRNGPID,	/* Wrong pid in netlink message */
47 	LIBBPF_ERRNO__INVSEQ,	/* Invalid netlink sequence */
48 	LIBBPF_ERRNO__NLPARSE,	/* netlink parsing error */
49 	__LIBBPF_ERRNO__END,
50 };
51 
52 LIBBPF_API int libbpf_strerror(int err, char *buf, size_t size);
53 
54 enum libbpf_print_level {
55         LIBBPF_WARN,
56         LIBBPF_INFO,
57         LIBBPF_DEBUG,
58 };
59 
60 typedef int (*libbpf_print_fn_t)(enum libbpf_print_level level,
61 				 const char *, va_list ap);
62 
63 LIBBPF_API libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn);
64 
65 /* Hide internal to user */
66 struct bpf_object;
67 
68 struct bpf_object_open_attr {
69 	const char *file;
70 	enum bpf_prog_type prog_type;
71 };
72 
73 struct bpf_object_open_opts {
74 	/* size of this struct, for forward/backward compatiblity */
75 	size_t sz;
76 	/* object name override, if provided:
77 	 * - for object open from file, this will override setting object
78 	 *   name from file path's base name;
79 	 * - for object open from memory buffer, this will specify an object
80 	 *   name and will override default "<addr>-<buf-size>" name;
81 	 */
82 	const char *object_name;
83 	/* parse map definitions non-strictly, allowing extra attributes/data */
84 	bool relaxed_maps;
85 	/* DEPRECATED: handle CO-RE relocations non-strictly, allowing failures.
86 	 * Value is ignored. Relocations always are processed non-strictly.
87 	 * Non-relocatable instructions are replaced with invalid ones to
88 	 * prevent accidental errors.
89 	 * */
90 	LIBBPF_DEPRECATED_SINCE(0, 6, "field has no effect")
91 	bool relaxed_core_relocs;
92 	/* maps that set the 'pinning' attribute in their definition will have
93 	 * their pin_path attribute set to a file in this directory, and be
94 	 * auto-pinned to that path on load; defaults to "/sys/fs/bpf".
95 	 */
96 	const char *pin_root_path;
97 
98 	LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__set_attach_target() on each individual bpf_program")
99 	__u32 attach_prog_fd;
100 	/* Additional kernel config content that augments and overrides
101 	 * system Kconfig for CONFIG_xxx externs.
102 	 */
103 	const char *kconfig;
104 	/* Path to the custom BTF to be used for BPF CO-RE relocations.
105 	 * This custom BTF completely replaces the use of vmlinux BTF
106 	 * for the purpose of CO-RE relocations.
107 	 * NOTE: any other BPF feature (e.g., fentry/fexit programs,
108 	 * struct_ops, etc) will need actual kernel BTF at /sys/kernel/btf/vmlinux.
109 	 */
110 	const char *btf_custom_path;
111 	/* Pointer to a buffer for storing kernel logs for applicable BPF
112 	 * commands. Valid kernel_log_size has to be specified as well and are
113 	 * passed-through to bpf() syscall. Keep in mind that kernel might
114 	 * fail operation with -ENOSPC error if provided buffer is too small
115 	 * to contain entire log output.
116 	 * See the comment below for kernel_log_level for interaction between
117 	 * log_buf and log_level settings.
118 	 *
119 	 * If specified, this log buffer will be passed for:
120 	 *   - each BPF progral load (BPF_PROG_LOAD) attempt, unless overriden
121 	 *     with bpf_program__set_log() on per-program level, to get
122 	 *     BPF verifier log output.
123 	 *   - during BPF object's BTF load into kernel (BPF_BTF_LOAD) to get
124 	 *     BTF sanity checking log.
125 	 *
126 	 * Each BPF command (BPF_BTF_LOAD or BPF_PROG_LOAD) will overwrite
127 	 * previous contents, so if you need more fine-grained control, set
128 	 * per-program buffer with bpf_program__set_log_buf() to preserve each
129 	 * individual program's verification log. Keep using kernel_log_buf
130 	 * for BTF verification log, if necessary.
131 	 */
132 	char *kernel_log_buf;
133 	size_t kernel_log_size;
134 	/*
135 	 * Log level can be set independently from log buffer. Log_level=0
136 	 * means that libbpf will attempt loading BTF or program without any
137 	 * logging requested, but will retry with either its own or custom log
138 	 * buffer, if provided, and log_level=1 on any error.
139 	 * And vice versa, setting log_level>0 will request BTF or prog
140 	 * loading with verbose log from the first attempt (and as such also
141 	 * for successfully loaded BTF or program), and the actual log buffer
142 	 * could be either libbpf's own auto-allocated log buffer, if
143 	 * kernel_log_buffer is NULL, or user-provided custom kernel_log_buf.
144 	 * If user didn't provide custom log buffer, libbpf will emit captured
145 	 * logs through its print callback.
146 	 */
147 	__u32 kernel_log_level;
148 
149 	size_t :0;
150 };
151 #define bpf_object_open_opts__last_field kernel_log_level
152 
153 LIBBPF_API struct bpf_object *bpf_object__open(const char *path);
154 
155 /**
156  * @brief **bpf_object__open_file()** creates a bpf_object by opening
157  * the BPF ELF object file pointed to by the passed path and loading it
158  * into memory.
159  * @param path BPF object file path
160  * @param opts options for how to load the bpf object, this parameter is
161  * optional and can be set to NULL
162  * @return pointer to the new bpf_object; or NULL is returned on error,
163  * error code is stored in errno
164  */
165 LIBBPF_API struct bpf_object *
166 bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts);
167 
168 /**
169  * @brief **bpf_object__open_mem()** creates a bpf_object by reading
170  * the BPF objects raw bytes from a memory buffer containing a valid
171  * BPF ELF object file.
172  * @param obj_buf pointer to the buffer containing ELF file bytes
173  * @param obj_buf_sz number of bytes in the buffer
174  * @param opts options for how to load the bpf object
175  * @return pointer to the new bpf_object; or NULL is returned on error,
176  * error code is stored in errno
177  */
178 LIBBPF_API struct bpf_object *
179 bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz,
180 		     const struct bpf_object_open_opts *opts);
181 
182 /* deprecated bpf_object__open variants */
183 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__open_mem() instead")
184 LIBBPF_API struct bpf_object *
185 bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz,
186 			const char *name);
187 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__open_file() instead")
188 LIBBPF_API struct bpf_object *
189 bpf_object__open_xattr(struct bpf_object_open_attr *attr);
190 
191 enum libbpf_pin_type {
192 	LIBBPF_PIN_NONE,
193 	/* PIN_BY_NAME: pin maps by name (in /sys/fs/bpf by default) */
194 	LIBBPF_PIN_BY_NAME,
195 };
196 
197 /* pin_maps and unpin_maps can both be called with a NULL path, in which case
198  * they will use the pin_path attribute of each map (and ignore all maps that
199  * don't have a pin_path set).
200  */
201 LIBBPF_API int bpf_object__pin_maps(struct bpf_object *obj, const char *path);
202 LIBBPF_API int bpf_object__unpin_maps(struct bpf_object *obj,
203 				      const char *path);
204 LIBBPF_API int bpf_object__pin_programs(struct bpf_object *obj,
205 					const char *path);
206 LIBBPF_API int bpf_object__unpin_programs(struct bpf_object *obj,
207 					  const char *path);
208 LIBBPF_API int bpf_object__pin(struct bpf_object *object, const char *path);
209 LIBBPF_API void bpf_object__close(struct bpf_object *object);
210 
211 struct bpf_object_load_attr {
212 	struct bpf_object *obj;
213 	int log_level;
214 	const char *target_btf_path;
215 };
216 
217 /* Load/unload object into/from kernel */
218 LIBBPF_API int bpf_object__load(struct bpf_object *obj);
219 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__load() instead")
220 LIBBPF_API int bpf_object__load_xattr(struct bpf_object_load_attr *attr);
221 LIBBPF_DEPRECATED_SINCE(0, 6, "bpf_object__unload() is deprecated, use bpf_object__close() instead")
222 LIBBPF_API int bpf_object__unload(struct bpf_object *obj);
223 
224 LIBBPF_API const char *bpf_object__name(const struct bpf_object *obj);
225 LIBBPF_API unsigned int bpf_object__kversion(const struct bpf_object *obj);
226 LIBBPF_API int bpf_object__set_kversion(struct bpf_object *obj, __u32 kern_version);
227 
228 struct btf;
229 LIBBPF_API struct btf *bpf_object__btf(const struct bpf_object *obj);
230 LIBBPF_API int bpf_object__btf_fd(const struct bpf_object *obj);
231 
232 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__find_program_by_name() instead")
233 LIBBPF_API struct bpf_program *
234 bpf_object__find_program_by_title(const struct bpf_object *obj,
235 				  const char *title);
236 LIBBPF_API struct bpf_program *
237 bpf_object__find_program_by_name(const struct bpf_object *obj,
238 				 const char *name);
239 
240 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "track bpf_objects in application code instead")
241 struct bpf_object *bpf_object__next(struct bpf_object *prev);
242 #define bpf_object__for_each_safe(pos, tmp)			\
243 	for ((pos) = bpf_object__next(NULL),		\
244 		(tmp) = bpf_object__next(pos);		\
245 	     (pos) != NULL;				\
246 	     (pos) = (tmp), (tmp) = bpf_object__next(tmp))
247 
248 typedef void (*bpf_object_clear_priv_t)(struct bpf_object *, void *);
249 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated")
250 LIBBPF_API int bpf_object__set_priv(struct bpf_object *obj, void *priv,
251 				    bpf_object_clear_priv_t clear_priv);
252 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated")
253 LIBBPF_API void *bpf_object__priv(const struct bpf_object *prog);
254 
255 LIBBPF_API int
256 libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type,
257 			 enum bpf_attach_type *expected_attach_type);
258 LIBBPF_API int libbpf_attach_type_by_name(const char *name,
259 					  enum bpf_attach_type *attach_type);
260 LIBBPF_API int libbpf_find_vmlinux_btf_id(const char *name,
261 					  enum bpf_attach_type attach_type);
262 
263 /* Accessors of bpf_program */
264 struct bpf_program;
265 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__next_program() instead")
266 struct bpf_program *bpf_program__next(struct bpf_program *prog,
267 				      const struct bpf_object *obj);
268 LIBBPF_API struct bpf_program *
269 bpf_object__next_program(const struct bpf_object *obj, struct bpf_program *prog);
270 
271 #define bpf_object__for_each_program(pos, obj)			\
272 	for ((pos) = bpf_object__next_program((obj), NULL);	\
273 	     (pos) != NULL;					\
274 	     (pos) = bpf_object__next_program((obj), (pos)))
275 
276 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__prev_program() instead")
277 struct bpf_program *bpf_program__prev(struct bpf_program *prog,
278 				      const struct bpf_object *obj);
279 LIBBPF_API struct bpf_program *
280 bpf_object__prev_program(const struct bpf_object *obj, struct bpf_program *prog);
281 
282 typedef void (*bpf_program_clear_priv_t)(struct bpf_program *, void *);
283 
284 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated")
285 LIBBPF_API int bpf_program__set_priv(struct bpf_program *prog, void *priv,
286 				     bpf_program_clear_priv_t clear_priv);
287 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated")
288 LIBBPF_API void *bpf_program__priv(const struct bpf_program *prog);
289 LIBBPF_API void bpf_program__set_ifindex(struct bpf_program *prog,
290 					 __u32 ifindex);
291 
292 LIBBPF_API const char *bpf_program__name(const struct bpf_program *prog);
293 LIBBPF_API const char *bpf_program__section_name(const struct bpf_program *prog);
294 LIBBPF_API LIBBPF_DEPRECATED("BPF program title is confusing term; please use bpf_program__section_name() instead")
295 const char *bpf_program__title(const struct bpf_program *prog, bool needs_copy);
296 LIBBPF_API bool bpf_program__autoload(const struct bpf_program *prog);
297 LIBBPF_API int bpf_program__set_autoload(struct bpf_program *prog, bool autoload);
298 
299 /* returns program size in bytes */
300 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insn_cnt() instead")
301 LIBBPF_API size_t bpf_program__size(const struct bpf_program *prog);
302 
303 struct bpf_insn;
304 
305 /**
306  * @brief **bpf_program__insns()** gives read-only access to BPF program's
307  * underlying BPF instructions.
308  * @param prog BPF program for which to return instructions
309  * @return a pointer to an array of BPF instructions that belong to the
310  * specified BPF program
311  *
312  * Returned pointer is always valid and not NULL. Number of `struct bpf_insn`
313  * pointed to can be fetched using **bpf_program__insn_cnt()** API.
314  *
315  * Keep in mind, libbpf can modify and append/delete BPF program's
316  * instructions as it processes BPF object file and prepares everything for
317  * uploading into the kernel. So depending on the point in BPF object
318  * lifetime, **bpf_program__insns()** can return different sets of
319  * instructions. As an example, during BPF object load phase BPF program
320  * instructions will be CO-RE-relocated, BPF subprograms instructions will be
321  * appended, ldimm64 instructions will have FDs embedded, etc. So instructions
322  * returned before **bpf_object__load()** and after it might be quite
323  * different.
324  */
325 LIBBPF_API const struct bpf_insn *bpf_program__insns(const struct bpf_program *prog);
326 
327 /**
328  * @brief **bpf_program__set_insns()** can set BPF program's underlying
329  * BPF instructions.
330  *
331  * WARNING: This is a very advanced libbpf API and users need to know
332  * what they are doing. This should be used from prog_prepare_load_fn
333  * callback only.
334  *
335  * @param prog BPF program for which to return instructions
336  * @param new_insns a pointer to an array of BPF instructions
337  * @param new_insn_cnt number of `struct bpf_insn`'s that form
338  * specified BPF program
339  * @return 0, on success; negative error code, otherwise
340  */
341 LIBBPF_API int bpf_program__set_insns(struct bpf_program *prog,
342 				      struct bpf_insn *new_insns, size_t new_insn_cnt);
343 
344 /**
345  * @brief **bpf_program__insn_cnt()** returns number of `struct bpf_insn`'s
346  * that form specified BPF program.
347  * @param prog BPF program for which to return number of BPF instructions
348  *
349  * See **bpf_program__insns()** documentation for notes on how libbpf can
350  * change instructions and their count during different phases of
351  * **bpf_object** lifetime.
352  */
353 LIBBPF_API size_t bpf_program__insn_cnt(const struct bpf_program *prog);
354 
355 LIBBPF_DEPRECATED_SINCE(0, 6, "use bpf_object__load() instead")
356 LIBBPF_API int bpf_program__load(struct bpf_program *prog, const char *license, __u32 kern_version);
357 LIBBPF_API int bpf_program__fd(const struct bpf_program *prog);
358 LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated")
359 LIBBPF_API int bpf_program__pin_instance(struct bpf_program *prog,
360 					 const char *path,
361 					 int instance);
362 LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated")
363 LIBBPF_API int bpf_program__unpin_instance(struct bpf_program *prog,
364 					   const char *path,
365 					   int instance);
366 
367 /**
368  * @brief **bpf_program__pin()** pins the BPF program to a file
369  * in the BPF FS specified by a path. This increments the programs
370  * reference count, allowing it to stay loaded after the process
371  * which loaded it has exited.
372  *
373  * @param prog BPF program to pin, must already be loaded
374  * @param path file path in a BPF file system
375  * @return 0, on success; negative error code, otherwise
376  */
377 LIBBPF_API int bpf_program__pin(struct bpf_program *prog, const char *path);
378 
379 /**
380  * @brief **bpf_program__unpin()** unpins the BPF program from a file
381  * in the BPFFS specified by a path. This decrements the programs
382  * reference count.
383  *
384  * The file pinning the BPF program can also be unlinked by a different
385  * process in which case this function will return an error.
386  *
387  * @param prog BPF program to unpin
388  * @param path file path to the pin in a BPF file system
389  * @return 0, on success; negative error code, otherwise
390  */
391 LIBBPF_API int bpf_program__unpin(struct bpf_program *prog, const char *path);
392 LIBBPF_API void bpf_program__unload(struct bpf_program *prog);
393 
394 struct bpf_link;
395 
396 LIBBPF_API struct bpf_link *bpf_link__open(const char *path);
397 LIBBPF_API int bpf_link__fd(const struct bpf_link *link);
398 LIBBPF_API const char *bpf_link__pin_path(const struct bpf_link *link);
399 /**
400  * @brief **bpf_link__pin()** pins the BPF link to a file
401  * in the BPF FS specified by a path. This increments the links
402  * reference count, allowing it to stay loaded after the process
403  * which loaded it has exited.
404  *
405  * @param link BPF link to pin, must already be loaded
406  * @param path file path in a BPF file system
407  * @return 0, on success; negative error code, otherwise
408  */
409 
410 LIBBPF_API int bpf_link__pin(struct bpf_link *link, const char *path);
411 
412 /**
413  * @brief **bpf_link__unpin()** unpins the BPF link from a file
414  * in the BPFFS specified by a path. This decrements the links
415  * reference count.
416  *
417  * The file pinning the BPF link can also be unlinked by a different
418  * process in which case this function will return an error.
419  *
420  * @param prog BPF program to unpin
421  * @param path file path to the pin in a BPF file system
422  * @return 0, on success; negative error code, otherwise
423  */
424 LIBBPF_API int bpf_link__unpin(struct bpf_link *link);
425 LIBBPF_API int bpf_link__update_program(struct bpf_link *link,
426 					struct bpf_program *prog);
427 LIBBPF_API void bpf_link__disconnect(struct bpf_link *link);
428 LIBBPF_API int bpf_link__detach(struct bpf_link *link);
429 LIBBPF_API int bpf_link__destroy(struct bpf_link *link);
430 
431 /**
432  * @brief **bpf_program__attach()** is a generic function for attaching
433  * a BPF program based on auto-detection of program type, attach type,
434  * and extra paremeters, where applicable.
435  *
436  * @param prog BPF program to attach
437  * @return Reference to the newly created BPF link; or NULL is returned on error,
438  * error code is stored in errno
439  *
440  * This is supported for:
441  *   - kprobe/kretprobe (depends on SEC() definition)
442  *   - uprobe/uretprobe (depends on SEC() definition)
443  *   - tracepoint
444  *   - raw tracepoint
445  *   - tracing programs (typed raw TP/fentry/fexit/fmod_ret)
446  */
447 LIBBPF_API struct bpf_link *
448 bpf_program__attach(const struct bpf_program *prog);
449 
450 struct bpf_perf_event_opts {
451 	/* size of this struct, for forward/backward compatiblity */
452 	size_t sz;
453 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
454 	__u64 bpf_cookie;
455 };
456 #define bpf_perf_event_opts__last_field bpf_cookie
457 
458 LIBBPF_API struct bpf_link *
459 bpf_program__attach_perf_event(const struct bpf_program *prog, int pfd);
460 
461 LIBBPF_API struct bpf_link *
462 bpf_program__attach_perf_event_opts(const struct bpf_program *prog, int pfd,
463 				    const struct bpf_perf_event_opts *opts);
464 
465 struct bpf_kprobe_opts {
466 	/* size of this struct, for forward/backward compatiblity */
467 	size_t sz;
468 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
469 	__u64 bpf_cookie;
470 	/* function's offset to install kprobe to */
471 	size_t offset;
472 	/* kprobe is return probe */
473 	bool retprobe;
474 	size_t :0;
475 };
476 #define bpf_kprobe_opts__last_field retprobe
477 
478 LIBBPF_API struct bpf_link *
479 bpf_program__attach_kprobe(const struct bpf_program *prog, bool retprobe,
480 			   const char *func_name);
481 LIBBPF_API struct bpf_link *
482 bpf_program__attach_kprobe_opts(const struct bpf_program *prog,
483                                 const char *func_name,
484                                 const struct bpf_kprobe_opts *opts);
485 
486 struct bpf_kprobe_multi_opts {
487 	/* size of this struct, for forward/backward compatibility */
488 	size_t sz;
489 	/* array of function symbols to attach */
490 	const char **syms;
491 	/* array of function addresses to attach */
492 	const unsigned long *addrs;
493 	/* array of user-provided values fetchable through bpf_get_attach_cookie */
494 	const __u64 *cookies;
495 	/* number of elements in syms/addrs/cookies arrays */
496 	size_t cnt;
497 	/* create return kprobes */
498 	bool retprobe;
499 	size_t :0;
500 };
501 
502 #define bpf_kprobe_multi_opts__last_field retprobe
503 
504 LIBBPF_API struct bpf_link *
505 bpf_program__attach_kprobe_multi_opts(const struct bpf_program *prog,
506 				      const char *pattern,
507 				      const struct bpf_kprobe_multi_opts *opts);
508 
509 struct bpf_uprobe_opts {
510 	/* size of this struct, for forward/backward compatiblity */
511 	size_t sz;
512 	/* offset of kernel reference counted USDT semaphore, added in
513 	 * a6ca88b241d5 ("trace_uprobe: support reference counter in fd-based uprobe")
514 	 */
515 	size_t ref_ctr_offset;
516 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
517 	__u64 bpf_cookie;
518 	/* uprobe is return probe, invoked at function return time */
519 	bool retprobe;
520 	/* Function name to attach to.  Could be an unqualified ("abc") or library-qualified
521 	 * "abc@LIBXYZ" name.  To specify function entry, func_name should be set while
522 	 * func_offset argument to bpf_prog__attach_uprobe_opts() should be 0.  To trace an
523 	 * offset within a function, specify func_name and use func_offset argument to specify
524 	 * offset within the function.  Shared library functions must specify the shared library
525 	 * binary_path.
526 	 */
527 	const char *func_name;
528 	size_t :0;
529 };
530 #define bpf_uprobe_opts__last_field func_name
531 
532 /**
533  * @brief **bpf_program__attach_uprobe()** attaches a BPF program
534  * to the userspace function which is found by binary path and
535  * offset. You can optionally specify a particular proccess to attach
536  * to. You can also optionally attach the program to the function
537  * exit instead of entry.
538  *
539  * @param prog BPF program to attach
540  * @param retprobe Attach to function exit
541  * @param pid Process ID to attach the uprobe to, 0 for self (own process),
542  * -1 for all processes
543  * @param binary_path Path to binary that contains the function symbol
544  * @param func_offset Offset within the binary of the function symbol
545  * @return Reference to the newly created BPF link; or NULL is returned on error,
546  * error code is stored in errno
547  */
548 LIBBPF_API struct bpf_link *
549 bpf_program__attach_uprobe(const struct bpf_program *prog, bool retprobe,
550 			   pid_t pid, const char *binary_path,
551 			   size_t func_offset);
552 
553 /**
554  * @brief **bpf_program__attach_uprobe_opts()** is just like
555  * bpf_program__attach_uprobe() except with a options struct
556  * for various configurations.
557  *
558  * @param prog BPF program to attach
559  * @param pid Process ID to attach the uprobe to, 0 for self (own process),
560  * -1 for all processes
561  * @param binary_path Path to binary that contains the function symbol
562  * @param func_offset Offset within the binary of the function symbol
563  * @param opts Options for altering program attachment
564  * @return Reference to the newly created BPF link; or NULL is returned on error,
565  * error code is stored in errno
566  */
567 LIBBPF_API struct bpf_link *
568 bpf_program__attach_uprobe_opts(const struct bpf_program *prog, pid_t pid,
569 				const char *binary_path, size_t func_offset,
570 				const struct bpf_uprobe_opts *opts);
571 
572 struct bpf_usdt_opts {
573 	/* size of this struct, for forward/backward compatibility */
574 	size_t sz;
575 	/* custom user-provided value accessible through usdt_cookie() */
576 	__u64 usdt_cookie;
577 	size_t :0;
578 };
579 #define bpf_usdt_opts__last_field usdt_cookie
580 
581 /**
582  * @brief **bpf_program__attach_usdt()** is just like
583  * bpf_program__attach_uprobe_opts() except it covers USDT (User-space
584  * Statically Defined Tracepoint) attachment, instead of attaching to
585  * user-space function entry or exit.
586  *
587  * @param prog BPF program to attach
588  * @param pid Process ID to attach the uprobe to, 0 for self (own process),
589  * -1 for all processes
590  * @param binary_path Path to binary that contains provided USDT probe
591  * @param usdt_provider USDT provider name
592  * @param usdt_name USDT probe name
593  * @param opts Options for altering program attachment
594  * @return Reference to the newly created BPF link; or NULL is returned on error,
595  * error code is stored in errno
596  */
597 LIBBPF_API struct bpf_link *
598 bpf_program__attach_usdt(const struct bpf_program *prog,
599 			 pid_t pid, const char *binary_path,
600 			 const char *usdt_provider, const char *usdt_name,
601 			 const struct bpf_usdt_opts *opts);
602 
603 struct bpf_tracepoint_opts {
604 	/* size of this struct, for forward/backward compatiblity */
605 	size_t sz;
606 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
607 	__u64 bpf_cookie;
608 };
609 #define bpf_tracepoint_opts__last_field bpf_cookie
610 
611 LIBBPF_API struct bpf_link *
612 bpf_program__attach_tracepoint(const struct bpf_program *prog,
613 			       const char *tp_category,
614 			       const char *tp_name);
615 LIBBPF_API struct bpf_link *
616 bpf_program__attach_tracepoint_opts(const struct bpf_program *prog,
617 				    const char *tp_category,
618 				    const char *tp_name,
619 				    const struct bpf_tracepoint_opts *opts);
620 
621 LIBBPF_API struct bpf_link *
622 bpf_program__attach_raw_tracepoint(const struct bpf_program *prog,
623 				   const char *tp_name);
624 
625 struct bpf_trace_opts {
626 	/* size of this struct, for forward/backward compatibility */
627 	size_t sz;
628 	/* custom user-provided value fetchable through bpf_get_attach_cookie() */
629 	__u64 cookie;
630 };
631 #define bpf_trace_opts__last_field cookie
632 
633 LIBBPF_API struct bpf_link *
634 bpf_program__attach_trace(const struct bpf_program *prog);
635 LIBBPF_API struct bpf_link *
636 bpf_program__attach_trace_opts(const struct bpf_program *prog, const struct bpf_trace_opts *opts);
637 
638 LIBBPF_API struct bpf_link *
639 bpf_program__attach_lsm(const struct bpf_program *prog);
640 LIBBPF_API struct bpf_link *
641 bpf_program__attach_cgroup(const struct bpf_program *prog, int cgroup_fd);
642 LIBBPF_API struct bpf_link *
643 bpf_program__attach_netns(const struct bpf_program *prog, int netns_fd);
644 LIBBPF_API struct bpf_link *
645 bpf_program__attach_xdp(const struct bpf_program *prog, int ifindex);
646 LIBBPF_API struct bpf_link *
647 bpf_program__attach_freplace(const struct bpf_program *prog,
648 			     int target_fd, const char *attach_func_name);
649 
650 struct bpf_map;
651 
652 LIBBPF_API struct bpf_link *bpf_map__attach_struct_ops(const struct bpf_map *map);
653 
654 struct bpf_iter_attach_opts {
655 	size_t sz; /* size of this struct for forward/backward compatibility */
656 	union bpf_iter_link_info *link_info;
657 	__u32 link_info_len;
658 };
659 #define bpf_iter_attach_opts__last_field link_info_len
660 
661 LIBBPF_API struct bpf_link *
662 bpf_program__attach_iter(const struct bpf_program *prog,
663 			 const struct bpf_iter_attach_opts *opts);
664 
665 /*
666  * Libbpf allows callers to adjust BPF programs before being loaded
667  * into kernel. One program in an object file can be transformed into
668  * multiple variants to be attached to different hooks.
669  *
670  * bpf_program_prep_t, bpf_program__set_prep and bpf_program__nth_fd
671  * form an API for this purpose.
672  *
673  * - bpf_program_prep_t:
674  *   Defines a 'preprocessor', which is a caller defined function
675  *   passed to libbpf through bpf_program__set_prep(), and will be
676  *   called before program is loaded. The processor should adjust
677  *   the program one time for each instance according to the instance id
678  *   passed to it.
679  *
680  * - bpf_program__set_prep:
681  *   Attaches a preprocessor to a BPF program. The number of instances
682  *   that should be created is also passed through this function.
683  *
684  * - bpf_program__nth_fd:
685  *   After the program is loaded, get resulting FD of a given instance
686  *   of the BPF program.
687  *
688  * If bpf_program__set_prep() is not used, the program would be loaded
689  * without adjustment during bpf_object__load(). The program has only
690  * one instance. In this case bpf_program__fd(prog) is equal to
691  * bpf_program__nth_fd(prog, 0).
692  */
693 struct bpf_prog_prep_result {
694 	/*
695 	 * If not NULL, load new instruction array.
696 	 * If set to NULL, don't load this instance.
697 	 */
698 	struct bpf_insn *new_insn_ptr;
699 	int new_insn_cnt;
700 
701 	/* If not NULL, result FD is written to it. */
702 	int *pfd;
703 };
704 
705 /*
706  * Parameters of bpf_program_prep_t:
707  *  - prog:	The bpf_program being loaded.
708  *  - n:	Index of instance being generated.
709  *  - insns:	BPF instructions array.
710  *  - insns_cnt:Number of instructions in insns.
711  *  - res:	Output parameter, result of transformation.
712  *
713  * Return value:
714  *  - Zero:	pre-processing success.
715  *  - Non-zero:	pre-processing error, stop loading.
716  */
717 typedef int (*bpf_program_prep_t)(struct bpf_program *prog, int n,
718 				  struct bpf_insn *insns, int insns_cnt,
719 				  struct bpf_prog_prep_result *res);
720 
721 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_program__insns() for getting bpf_program instructions")
722 LIBBPF_API int bpf_program__set_prep(struct bpf_program *prog, int nr_instance,
723 				     bpf_program_prep_t prep);
724 
725 LIBBPF_DEPRECATED_SINCE(0, 7, "multi-instance bpf_program support is deprecated")
726 LIBBPF_API int bpf_program__nth_fd(const struct bpf_program *prog, int n);
727 
728 /*
729  * Adjust type of BPF program. Default is kprobe.
730  */
731 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
732 LIBBPF_API int bpf_program__set_socket_filter(struct bpf_program *prog);
733 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
734 LIBBPF_API int bpf_program__set_tracepoint(struct bpf_program *prog);
735 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
736 LIBBPF_API int bpf_program__set_raw_tracepoint(struct bpf_program *prog);
737 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
738 LIBBPF_API int bpf_program__set_kprobe(struct bpf_program *prog);
739 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
740 LIBBPF_API int bpf_program__set_lsm(struct bpf_program *prog);
741 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
742 LIBBPF_API int bpf_program__set_sched_cls(struct bpf_program *prog);
743 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
744 LIBBPF_API int bpf_program__set_sched_act(struct bpf_program *prog);
745 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
746 LIBBPF_API int bpf_program__set_xdp(struct bpf_program *prog);
747 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
748 LIBBPF_API int bpf_program__set_perf_event(struct bpf_program *prog);
749 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
750 LIBBPF_API int bpf_program__set_tracing(struct bpf_program *prog);
751 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
752 LIBBPF_API int bpf_program__set_struct_ops(struct bpf_program *prog);
753 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
754 LIBBPF_API int bpf_program__set_extension(struct bpf_program *prog);
755 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__set_type() instead")
756 LIBBPF_API int bpf_program__set_sk_lookup(struct bpf_program *prog);
757 
758 LIBBPF_API enum bpf_prog_type bpf_program__type(const struct bpf_program *prog);
759 
760 /**
761  * @brief **bpf_program__set_type()** sets the program
762  * type of the passed BPF program.
763  * @param prog BPF program to set the program type for
764  * @param type program type to set the BPF map to have
765  * @return error code; or 0 if no error. An error occurs
766  * if the object is already loaded.
767  *
768  * This must be called before the BPF object is loaded,
769  * otherwise it has no effect and an error is returned.
770  */
771 LIBBPF_API int bpf_program__set_type(struct bpf_program *prog,
772 				     enum bpf_prog_type type);
773 
774 LIBBPF_API enum bpf_attach_type
775 bpf_program__expected_attach_type(const struct bpf_program *prog);
776 
777 /**
778  * @brief **bpf_program__set_expected_attach_type()** sets the
779  * attach type of the passed BPF program. This is used for
780  * auto-detection of attachment when programs are loaded.
781  * @param prog BPF program to set the attach type for
782  * @param type attach type to set the BPF map to have
783  * @return error code; or 0 if no error. An error occurs
784  * if the object is already loaded.
785  *
786  * This must be called before the BPF object is loaded,
787  * otherwise it has no effect and an error is returned.
788  */
789 LIBBPF_API int
790 bpf_program__set_expected_attach_type(struct bpf_program *prog,
791 				      enum bpf_attach_type type);
792 
793 LIBBPF_API __u32 bpf_program__flags(const struct bpf_program *prog);
794 LIBBPF_API int bpf_program__set_flags(struct bpf_program *prog, __u32 flags);
795 
796 /* Per-program log level and log buffer getters/setters.
797  * See bpf_object_open_opts comments regarding log_level and log_buf
798  * interactions.
799  */
800 LIBBPF_API __u32 bpf_program__log_level(const struct bpf_program *prog);
801 LIBBPF_API int bpf_program__set_log_level(struct bpf_program *prog, __u32 log_level);
802 LIBBPF_API const char *bpf_program__log_buf(const struct bpf_program *prog, size_t *log_size);
803 LIBBPF_API int bpf_program__set_log_buf(struct bpf_program *prog, char *log_buf, size_t log_size);
804 
805 /**
806  * @brief **bpf_program__set_attach_target()** sets BTF-based attach target
807  * for supported BPF program types:
808  *   - BTF-aware raw tracepoints (tp_btf);
809  *   - fentry/fexit/fmod_ret;
810  *   - lsm;
811  *   - freplace.
812  * @param prog BPF program to set the attach type for
813  * @param type attach type to set the BPF map to have
814  * @return error code; or 0 if no error occurred.
815  */
816 LIBBPF_API int
817 bpf_program__set_attach_target(struct bpf_program *prog, int attach_prog_fd,
818 			       const char *attach_func_name);
819 
820 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
821 LIBBPF_API bool bpf_program__is_socket_filter(const struct bpf_program *prog);
822 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
823 LIBBPF_API bool bpf_program__is_tracepoint(const struct bpf_program *prog);
824 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
825 LIBBPF_API bool bpf_program__is_raw_tracepoint(const struct bpf_program *prog);
826 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
827 LIBBPF_API bool bpf_program__is_kprobe(const struct bpf_program *prog);
828 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
829 LIBBPF_API bool bpf_program__is_lsm(const struct bpf_program *prog);
830 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
831 LIBBPF_API bool bpf_program__is_sched_cls(const struct bpf_program *prog);
832 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
833 LIBBPF_API bool bpf_program__is_sched_act(const struct bpf_program *prog);
834 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
835 LIBBPF_API bool bpf_program__is_xdp(const struct bpf_program *prog);
836 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
837 LIBBPF_API bool bpf_program__is_perf_event(const struct bpf_program *prog);
838 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
839 LIBBPF_API bool bpf_program__is_tracing(const struct bpf_program *prog);
840 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
841 LIBBPF_API bool bpf_program__is_struct_ops(const struct bpf_program *prog);
842 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
843 LIBBPF_API bool bpf_program__is_extension(const struct bpf_program *prog);
844 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_program__type() instead")
845 LIBBPF_API bool bpf_program__is_sk_lookup(const struct bpf_program *prog);
846 
847 /*
848  * No need for __attribute__((packed)), all members of 'bpf_map_def'
849  * are all aligned.  In addition, using __attribute__((packed))
850  * would trigger a -Wpacked warning message, and lead to an error
851  * if -Werror is set.
852  */
853 struct bpf_map_def {
854 	unsigned int type;
855 	unsigned int key_size;
856 	unsigned int value_size;
857 	unsigned int max_entries;
858 	unsigned int map_flags;
859 };
860 
861 /**
862  * @brief **bpf_object__find_map_by_name()** returns BPF map of
863  * the given name, if it exists within the passed BPF object
864  * @param obj BPF object
865  * @param name name of the BPF map
866  * @return BPF map instance, if such map exists within the BPF object;
867  * or NULL otherwise.
868  */
869 LIBBPF_API struct bpf_map *
870 bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name);
871 
872 LIBBPF_API int
873 bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name);
874 
875 /*
876  * Get bpf_map through the offset of corresponding struct bpf_map_def
877  * in the BPF object file.
878  */
879 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__find_map_by_name() instead")
880 struct bpf_map *
881 bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset);
882 
883 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__next_map() instead")
884 struct bpf_map *bpf_map__next(const struct bpf_map *map, const struct bpf_object *obj);
885 LIBBPF_API struct bpf_map *
886 bpf_object__next_map(const struct bpf_object *obj, const struct bpf_map *map);
887 
888 #define bpf_object__for_each_map(pos, obj)		\
889 	for ((pos) = bpf_object__next_map((obj), NULL);	\
890 	     (pos) != NULL;				\
891 	     (pos) = bpf_object__next_map((obj), (pos)))
892 #define bpf_map__for_each bpf_object__for_each_map
893 
894 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__prev_map() instead")
895 struct bpf_map *bpf_map__prev(const struct bpf_map *map, const struct bpf_object *obj);
896 LIBBPF_API struct bpf_map *
897 bpf_object__prev_map(const struct bpf_object *obj, const struct bpf_map *map);
898 
899 /**
900  * @brief **bpf_map__set_autocreate()** sets whether libbpf has to auto-create
901  * BPF map during BPF object load phase.
902  * @param map the BPF map instance
903  * @param autocreate whether to create BPF map during BPF object load
904  * @return 0 on success; -EBUSY if BPF object was already loaded
905  *
906  * **bpf_map__set_autocreate()** allows to opt-out from libbpf auto-creating
907  * BPF map. By default, libbpf will attempt to create every single BPF map
908  * defined in BPF object file using BPF_MAP_CREATE command of bpf() syscall
909  * and fill in map FD in BPF instructions.
910  *
911  * This API allows to opt-out of this process for specific map instance. This
912  * can be useful if host kernel doesn't support such BPF map type or used
913  * combination of flags and user application wants to avoid creating such
914  * a map in the first place. User is still responsible to make sure that their
915  * BPF-side code that expects to use such missing BPF map is recognized by BPF
916  * verifier as dead code, otherwise BPF verifier will reject such BPF program.
917  */
918 LIBBPF_API int bpf_map__set_autocreate(struct bpf_map *map, bool autocreate);
919 LIBBPF_API bool bpf_map__autocreate(const struct bpf_map *map);
920 
921 /**
922  * @brief **bpf_map__fd()** gets the file descriptor of the passed
923  * BPF map
924  * @param map the BPF map instance
925  * @return the file descriptor; or -EINVAL in case of an error
926  */
927 LIBBPF_API int bpf_map__fd(const struct bpf_map *map);
928 LIBBPF_API int bpf_map__reuse_fd(struct bpf_map *map, int fd);
929 /* get map definition */
930 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 8, "use appropriate getters or setters instead")
931 const struct bpf_map_def *bpf_map__def(const struct bpf_map *map);
932 /* get map name */
933 LIBBPF_API const char *bpf_map__name(const struct bpf_map *map);
934 /* get/set map type */
935 LIBBPF_API enum bpf_map_type bpf_map__type(const struct bpf_map *map);
936 LIBBPF_API int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type);
937 /* get/set map size (max_entries) */
938 LIBBPF_API __u32 bpf_map__max_entries(const struct bpf_map *map);
939 LIBBPF_API int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries);
940 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_map__set_max_entries() instead")
941 LIBBPF_API int bpf_map__resize(struct bpf_map *map, __u32 max_entries);
942 /* get/set map flags */
943 LIBBPF_API __u32 bpf_map__map_flags(const struct bpf_map *map);
944 LIBBPF_API int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags);
945 /* get/set map NUMA node */
946 LIBBPF_API __u32 bpf_map__numa_node(const struct bpf_map *map);
947 LIBBPF_API int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node);
948 /* get/set map key size */
949 LIBBPF_API __u32 bpf_map__key_size(const struct bpf_map *map);
950 LIBBPF_API int bpf_map__set_key_size(struct bpf_map *map, __u32 size);
951 /* get/set map value size */
952 LIBBPF_API __u32 bpf_map__value_size(const struct bpf_map *map);
953 LIBBPF_API int bpf_map__set_value_size(struct bpf_map *map, __u32 size);
954 /* get map key/value BTF type IDs */
955 LIBBPF_API __u32 bpf_map__btf_key_type_id(const struct bpf_map *map);
956 LIBBPF_API __u32 bpf_map__btf_value_type_id(const struct bpf_map *map);
957 /* get/set map if_index */
958 LIBBPF_API __u32 bpf_map__ifindex(const struct bpf_map *map);
959 LIBBPF_API int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex);
960 /* get/set map map_extra flags */
961 LIBBPF_API __u64 bpf_map__map_extra(const struct bpf_map *map);
962 LIBBPF_API int bpf_map__set_map_extra(struct bpf_map *map, __u64 map_extra);
963 
964 typedef void (*bpf_map_clear_priv_t)(struct bpf_map *, void *);
965 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated")
966 LIBBPF_API int bpf_map__set_priv(struct bpf_map *map, void *priv,
967 				 bpf_map_clear_priv_t clear_priv);
968 LIBBPF_DEPRECATED_SINCE(0, 7, "storage via set_priv/priv is deprecated")
969 LIBBPF_API void *bpf_map__priv(const struct bpf_map *map);
970 LIBBPF_API int bpf_map__set_initial_value(struct bpf_map *map,
971 					  const void *data, size_t size);
972 LIBBPF_API const void *bpf_map__initial_value(struct bpf_map *map, size_t *psize);
973 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_map__type() instead")
974 LIBBPF_API bool bpf_map__is_offload_neutral(const struct bpf_map *map);
975 
976 /**
977  * @brief **bpf_map__is_internal()** tells the caller whether or not the
978  * passed map is a special map created by libbpf automatically for things like
979  * global variables, __ksym externs, Kconfig values, etc
980  * @param map the bpf_map
981  * @return true, if the map is an internal map; false, otherwise
982  */
983 LIBBPF_API bool bpf_map__is_internal(const struct bpf_map *map);
984 LIBBPF_API int bpf_map__set_pin_path(struct bpf_map *map, const char *path);
985 LIBBPF_API const char *bpf_map__pin_path(const struct bpf_map *map);
986 LIBBPF_API bool bpf_map__is_pinned(const struct bpf_map *map);
987 LIBBPF_API int bpf_map__pin(struct bpf_map *map, const char *path);
988 LIBBPF_API int bpf_map__unpin(struct bpf_map *map, const char *path);
989 
990 LIBBPF_API int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd);
991 LIBBPF_API struct bpf_map *bpf_map__inner_map(struct bpf_map *map);
992 
993 /**
994  * @brief **bpf_map__lookup_elem()** allows to lookup BPF map value
995  * corresponding to provided key.
996  * @param map BPF map to lookup element in
997  * @param key pointer to memory containing bytes of the key used for lookup
998  * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
999  * @param value pointer to memory in which looked up value will be stored
1000  * @param value_sz size in byte of value data memory; it has to match BPF map
1001  * definition's **value_size**. For per-CPU BPF maps value size has to be
1002  * a product of BPF map value size and number of possible CPUs in the system
1003  * (could be fetched with **libbpf_num_possible_cpus()**). Note also that for
1004  * per-CPU values value size has to be aligned up to closest 8 bytes for
1005  * alignment reasons, so expected size is: `round_up(value_size, 8)
1006  * * libbpf_num_possible_cpus()`.
1007  * @flags extra flags passed to kernel for this operation
1008  * @return 0, on success; negative error, otherwise
1009  *
1010  * **bpf_map__lookup_elem()** is high-level equivalent of
1011  * **bpf_map_lookup_elem()** API with added check for key and value size.
1012  */
1013 LIBBPF_API int bpf_map__lookup_elem(const struct bpf_map *map,
1014 				    const void *key, size_t key_sz,
1015 				    void *value, size_t value_sz, __u64 flags);
1016 
1017 /**
1018  * @brief **bpf_map__update_elem()** allows to insert or update value in BPF
1019  * map that corresponds to provided key.
1020  * @param map BPF map to insert to or update element in
1021  * @param key pointer to memory containing bytes of the key
1022  * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
1023  * @param value pointer to memory containing bytes of the value
1024  * @param value_sz size in byte of value data memory; it has to match BPF map
1025  * definition's **value_size**. For per-CPU BPF maps value size has to be
1026  * a product of BPF map value size and number of possible CPUs in the system
1027  * (could be fetched with **libbpf_num_possible_cpus()**). Note also that for
1028  * per-CPU values value size has to be aligned up to closest 8 bytes for
1029  * alignment reasons, so expected size is: `round_up(value_size, 8)
1030  * * libbpf_num_possible_cpus()`.
1031  * @flags extra flags passed to kernel for this operation
1032  * @return 0, on success; negative error, otherwise
1033  *
1034  * **bpf_map__update_elem()** is high-level equivalent of
1035  * **bpf_map_update_elem()** API with added check for key and value size.
1036  */
1037 LIBBPF_API int bpf_map__update_elem(const struct bpf_map *map,
1038 				    const void *key, size_t key_sz,
1039 				    const void *value, size_t value_sz, __u64 flags);
1040 
1041 /**
1042  * @brief **bpf_map__delete_elem()** allows to delete element in BPF map that
1043  * corresponds to provided key.
1044  * @param map BPF map to delete element from
1045  * @param key pointer to memory containing bytes of the key
1046  * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
1047  * @flags extra flags passed to kernel for this operation
1048  * @return 0, on success; negative error, otherwise
1049  *
1050  * **bpf_map__delete_elem()** is high-level equivalent of
1051  * **bpf_map_delete_elem()** API with added check for key size.
1052  */
1053 LIBBPF_API int bpf_map__delete_elem(const struct bpf_map *map,
1054 				    const void *key, size_t key_sz, __u64 flags);
1055 
1056 /**
1057  * @brief **bpf_map__lookup_and_delete_elem()** allows to lookup BPF map value
1058  * corresponding to provided key and atomically delete it afterwards.
1059  * @param map BPF map to lookup element in
1060  * @param key pointer to memory containing bytes of the key used for lookup
1061  * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
1062  * @param value pointer to memory in which looked up value will be stored
1063  * @param value_sz size in byte of value data memory; it has to match BPF map
1064  * definition's **value_size**. For per-CPU BPF maps value size has to be
1065  * a product of BPF map value size and number of possible CPUs in the system
1066  * (could be fetched with **libbpf_num_possible_cpus()**). Note also that for
1067  * per-CPU values value size has to be aligned up to closest 8 bytes for
1068  * alignment reasons, so expected size is: `round_up(value_size, 8)
1069  * * libbpf_num_possible_cpus()`.
1070  * @flags extra flags passed to kernel for this operation
1071  * @return 0, on success; negative error, otherwise
1072  *
1073  * **bpf_map__lookup_and_delete_elem()** is high-level equivalent of
1074  * **bpf_map_lookup_and_delete_elem()** API with added check for key and value size.
1075  */
1076 LIBBPF_API int bpf_map__lookup_and_delete_elem(const struct bpf_map *map,
1077 					       const void *key, size_t key_sz,
1078 					       void *value, size_t value_sz, __u64 flags);
1079 
1080 /**
1081  * @brief **bpf_map__get_next_key()** allows to iterate BPF map keys by
1082  * fetching next key that follows current key.
1083  * @param map BPF map to fetch next key from
1084  * @param cur_key pointer to memory containing bytes of current key or NULL to
1085  * fetch the first key
1086  * @param next_key pointer to memory to write next key into
1087  * @param key_sz size in bytes of key data, needs to match BPF map definition's **key_size**
1088  * @return 0, on success; -ENOENT if **cur_key** is the last key in BPF map;
1089  * negative error, otherwise
1090  *
1091  * **bpf_map__get_next_key()** is high-level equivalent of
1092  * **bpf_map_get_next_key()** API with added check for key size.
1093  */
1094 LIBBPF_API int bpf_map__get_next_key(const struct bpf_map *map,
1095 				     const void *cur_key, void *next_key, size_t key_sz);
1096 
1097 /**
1098  * @brief **libbpf_get_error()** extracts the error code from the passed
1099  * pointer
1100  * @param ptr pointer returned from libbpf API function
1101  * @return error code; or 0 if no error occured
1102  *
1103  * Many libbpf API functions which return pointers have logic to encode error
1104  * codes as pointers, and do not return NULL. Meaning **libbpf_get_error()**
1105  * should be used on the return value from these functions immediately after
1106  * calling the API function, with no intervening calls that could clobber the
1107  * `errno` variable. Consult the individual functions documentation to verify
1108  * if this logic applies should be used.
1109  *
1110  * For these API functions, if `libbpf_set_strict_mode(LIBBPF_STRICT_CLEAN_PTRS)`
1111  * is enabled, NULL is returned on error instead.
1112  *
1113  * If ptr is NULL, then errno should be already set by the failing
1114  * API, because libbpf never returns NULL on success and it now always
1115  * sets errno on error.
1116  *
1117  * Example usage:
1118  *
1119  *   struct perf_buffer *pb;
1120  *
1121  *   pb = perf_buffer__new(bpf_map__fd(obj->maps.events), PERF_BUFFER_PAGES, &opts);
1122  *   err = libbpf_get_error(pb);
1123  *   if (err) {
1124  *	  pb = NULL;
1125  *	  fprintf(stderr, "failed to open perf buffer: %d\n", err);
1126  *	  goto cleanup;
1127  *   }
1128  */
1129 LIBBPF_API long libbpf_get_error(const void *ptr);
1130 
1131 struct bpf_prog_load_attr {
1132 	const char *file;
1133 	enum bpf_prog_type prog_type;
1134 	enum bpf_attach_type expected_attach_type;
1135 	int ifindex;
1136 	int log_level;
1137 	int prog_flags;
1138 };
1139 
1140 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_object__open() and bpf_object__load() instead")
1141 LIBBPF_API int bpf_prog_load_xattr(const struct bpf_prog_load_attr *attr,
1142 				   struct bpf_object **pobj, int *prog_fd);
1143 LIBBPF_DEPRECATED_SINCE(0, 7, "use bpf_object__open() and bpf_object__load() instead")
1144 LIBBPF_API int bpf_prog_load_deprecated(const char *file, enum bpf_prog_type type,
1145 					struct bpf_object **pobj, int *prog_fd);
1146 
1147 /* XDP related API */
1148 struct xdp_link_info {
1149 	__u32 prog_id;
1150 	__u32 drv_prog_id;
1151 	__u32 hw_prog_id;
1152 	__u32 skb_prog_id;
1153 	__u8 attach_mode;
1154 };
1155 
1156 struct bpf_xdp_set_link_opts {
1157 	size_t sz;
1158 	int old_fd;
1159 	size_t :0;
1160 };
1161 #define bpf_xdp_set_link_opts__last_field old_fd
1162 
1163 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_xdp_attach() instead")
1164 LIBBPF_API int bpf_set_link_xdp_fd(int ifindex, int fd, __u32 flags);
1165 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_xdp_attach() instead")
1166 LIBBPF_API int bpf_set_link_xdp_fd_opts(int ifindex, int fd, __u32 flags,
1167 					const struct bpf_xdp_set_link_opts *opts);
1168 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_xdp_query_id() instead")
1169 LIBBPF_API int bpf_get_link_xdp_id(int ifindex, __u32 *prog_id, __u32 flags);
1170 LIBBPF_DEPRECATED_SINCE(0, 8, "use bpf_xdp_query() instead")
1171 LIBBPF_API int bpf_get_link_xdp_info(int ifindex, struct xdp_link_info *info,
1172 				     size_t info_size, __u32 flags);
1173 
1174 struct bpf_xdp_attach_opts {
1175 	size_t sz;
1176 	int old_prog_fd;
1177 	size_t :0;
1178 };
1179 #define bpf_xdp_attach_opts__last_field old_prog_fd
1180 
1181 struct bpf_xdp_query_opts {
1182 	size_t sz;
1183 	__u32 prog_id;		/* output */
1184 	__u32 drv_prog_id;	/* output */
1185 	__u32 hw_prog_id;	/* output */
1186 	__u32 skb_prog_id;	/* output */
1187 	__u8 attach_mode;	/* output */
1188 	size_t :0;
1189 };
1190 #define bpf_xdp_query_opts__last_field attach_mode
1191 
1192 LIBBPF_API int bpf_xdp_attach(int ifindex, int prog_fd, __u32 flags,
1193 			      const struct bpf_xdp_attach_opts *opts);
1194 LIBBPF_API int bpf_xdp_detach(int ifindex, __u32 flags,
1195 			      const struct bpf_xdp_attach_opts *opts);
1196 LIBBPF_API int bpf_xdp_query(int ifindex, int flags, struct bpf_xdp_query_opts *opts);
1197 LIBBPF_API int bpf_xdp_query_id(int ifindex, int flags, __u32 *prog_id);
1198 
1199 /* TC related API */
1200 enum bpf_tc_attach_point {
1201 	BPF_TC_INGRESS = 1 << 0,
1202 	BPF_TC_EGRESS  = 1 << 1,
1203 	BPF_TC_CUSTOM  = 1 << 2,
1204 };
1205 
1206 #define BPF_TC_PARENT(a, b) 	\
1207 	((((a) << 16) & 0xFFFF0000U) | ((b) & 0x0000FFFFU))
1208 
1209 enum bpf_tc_flags {
1210 	BPF_TC_F_REPLACE = 1 << 0,
1211 };
1212 
1213 struct bpf_tc_hook {
1214 	size_t sz;
1215 	int ifindex;
1216 	enum bpf_tc_attach_point attach_point;
1217 	__u32 parent;
1218 	size_t :0;
1219 };
1220 #define bpf_tc_hook__last_field parent
1221 
1222 struct bpf_tc_opts {
1223 	size_t sz;
1224 	int prog_fd;
1225 	__u32 flags;
1226 	__u32 prog_id;
1227 	__u32 handle;
1228 	__u32 priority;
1229 	size_t :0;
1230 };
1231 #define bpf_tc_opts__last_field priority
1232 
1233 LIBBPF_API int bpf_tc_hook_create(struct bpf_tc_hook *hook);
1234 LIBBPF_API int bpf_tc_hook_destroy(struct bpf_tc_hook *hook);
1235 LIBBPF_API int bpf_tc_attach(const struct bpf_tc_hook *hook,
1236 			     struct bpf_tc_opts *opts);
1237 LIBBPF_API int bpf_tc_detach(const struct bpf_tc_hook *hook,
1238 			     const struct bpf_tc_opts *opts);
1239 LIBBPF_API int bpf_tc_query(const struct bpf_tc_hook *hook,
1240 			    struct bpf_tc_opts *opts);
1241 
1242 /* Ring buffer APIs */
1243 struct ring_buffer;
1244 
1245 typedef int (*ring_buffer_sample_fn)(void *ctx, void *data, size_t size);
1246 
1247 struct ring_buffer_opts {
1248 	size_t sz; /* size of this struct, for forward/backward compatiblity */
1249 };
1250 
1251 #define ring_buffer_opts__last_field sz
1252 
1253 LIBBPF_API struct ring_buffer *
1254 ring_buffer__new(int map_fd, ring_buffer_sample_fn sample_cb, void *ctx,
1255 		 const struct ring_buffer_opts *opts);
1256 LIBBPF_API void ring_buffer__free(struct ring_buffer *rb);
1257 LIBBPF_API int ring_buffer__add(struct ring_buffer *rb, int map_fd,
1258 				ring_buffer_sample_fn sample_cb, void *ctx);
1259 LIBBPF_API int ring_buffer__poll(struct ring_buffer *rb, int timeout_ms);
1260 LIBBPF_API int ring_buffer__consume(struct ring_buffer *rb);
1261 LIBBPF_API int ring_buffer__epoll_fd(const struct ring_buffer *rb);
1262 
1263 /* Perf buffer APIs */
1264 struct perf_buffer;
1265 
1266 typedef void (*perf_buffer_sample_fn)(void *ctx, int cpu,
1267 				      void *data, __u32 size);
1268 typedef void (*perf_buffer_lost_fn)(void *ctx, int cpu, __u64 cnt);
1269 
1270 /* common use perf buffer options */
1271 struct perf_buffer_opts {
1272 	union {
1273 		size_t sz;
1274 		struct { /* DEPRECATED: will be removed in v1.0 */
1275 			/* if specified, sample_cb is called for each sample */
1276 			perf_buffer_sample_fn sample_cb;
1277 			/* if specified, lost_cb is called for each batch of lost samples */
1278 			perf_buffer_lost_fn lost_cb;
1279 			/* ctx is provided to sample_cb and lost_cb */
1280 			void *ctx;
1281 		};
1282 	};
1283 };
1284 #define perf_buffer_opts__last_field sz
1285 
1286 /**
1287  * @brief **perf_buffer__new()** creates BPF perfbuf manager for a specified
1288  * BPF_PERF_EVENT_ARRAY map
1289  * @param map_fd FD of BPF_PERF_EVENT_ARRAY BPF map that will be used by BPF
1290  * code to send data over to user-space
1291  * @param page_cnt number of memory pages allocated for each per-CPU buffer
1292  * @param sample_cb function called on each received data record
1293  * @param lost_cb function called when record loss has occurred
1294  * @param ctx user-provided extra context passed into *sample_cb* and *lost_cb*
1295  * @return a new instance of struct perf_buffer on success, NULL on error with
1296  * *errno* containing an error code
1297  */
1298 LIBBPF_API struct perf_buffer *
1299 perf_buffer__new(int map_fd, size_t page_cnt,
1300 		 perf_buffer_sample_fn sample_cb, perf_buffer_lost_fn lost_cb, void *ctx,
1301 		 const struct perf_buffer_opts *opts);
1302 
1303 LIBBPF_API struct perf_buffer *
1304 perf_buffer__new_v0_6_0(int map_fd, size_t page_cnt,
1305 			perf_buffer_sample_fn sample_cb, perf_buffer_lost_fn lost_cb, void *ctx,
1306 			const struct perf_buffer_opts *opts);
1307 
1308 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use new variant of perf_buffer__new() instead")
1309 struct perf_buffer *perf_buffer__new_deprecated(int map_fd, size_t page_cnt,
1310 						const struct perf_buffer_opts *opts);
1311 
1312 #define perf_buffer__new(...) ___libbpf_overload(___perf_buffer_new, __VA_ARGS__)
1313 #define ___perf_buffer_new6(map_fd, page_cnt, sample_cb, lost_cb, ctx, opts) \
1314 	perf_buffer__new(map_fd, page_cnt, sample_cb, lost_cb, ctx, opts)
1315 #define ___perf_buffer_new3(map_fd, page_cnt, opts) \
1316 	perf_buffer__new_deprecated(map_fd, page_cnt, opts)
1317 
1318 enum bpf_perf_event_ret {
1319 	LIBBPF_PERF_EVENT_DONE	= 0,
1320 	LIBBPF_PERF_EVENT_ERROR	= -1,
1321 	LIBBPF_PERF_EVENT_CONT	= -2,
1322 };
1323 
1324 struct perf_event_header;
1325 
1326 typedef enum bpf_perf_event_ret
1327 (*perf_buffer_event_fn)(void *ctx, int cpu, struct perf_event_header *event);
1328 
1329 /* raw perf buffer options, giving most power and control */
1330 struct perf_buffer_raw_opts {
1331 	union {
1332 		struct {
1333 			size_t sz;
1334 			long :0;
1335 			long :0;
1336 		};
1337 		struct { /* DEPRECATED: will be removed in v1.0 */
1338 			/* perf event attrs passed directly into perf_event_open() */
1339 			struct perf_event_attr *attr;
1340 			/* raw event callback */
1341 			perf_buffer_event_fn event_cb;
1342 			/* ctx is provided to event_cb */
1343 			void *ctx;
1344 		};
1345 	};
1346 	/* if cpu_cnt == 0, open all on all possible CPUs (up to the number of
1347 	 * max_entries of given PERF_EVENT_ARRAY map)
1348 	 */
1349 	int cpu_cnt;
1350 	/* if cpu_cnt > 0, cpus is an array of CPUs to open ring buffers on */
1351 	int *cpus;
1352 	/* if cpu_cnt > 0, map_keys specify map keys to set per-CPU FDs for */
1353 	int *map_keys;
1354 };
1355 #define perf_buffer_raw_opts__last_field map_keys
1356 
1357 LIBBPF_API struct perf_buffer *
1358 perf_buffer__new_raw(int map_fd, size_t page_cnt, struct perf_event_attr *attr,
1359 		     perf_buffer_event_fn event_cb, void *ctx,
1360 		     const struct perf_buffer_raw_opts *opts);
1361 
1362 LIBBPF_API struct perf_buffer *
1363 perf_buffer__new_raw_v0_6_0(int map_fd, size_t page_cnt, struct perf_event_attr *attr,
1364 			    perf_buffer_event_fn event_cb, void *ctx,
1365 			    const struct perf_buffer_raw_opts *opts);
1366 
1367 LIBBPF_API LIBBPF_DEPRECATED_SINCE(0, 7, "use new variant of perf_buffer__new_raw() instead")
1368 struct perf_buffer *perf_buffer__new_raw_deprecated(int map_fd, size_t page_cnt,
1369 						    const struct perf_buffer_raw_opts *opts);
1370 
1371 #define perf_buffer__new_raw(...) ___libbpf_overload(___perf_buffer_new_raw, __VA_ARGS__)
1372 #define ___perf_buffer_new_raw6(map_fd, page_cnt, attr, event_cb, ctx, opts) \
1373 	perf_buffer__new_raw(map_fd, page_cnt, attr, event_cb, ctx, opts)
1374 #define ___perf_buffer_new_raw3(map_fd, page_cnt, opts) \
1375 	perf_buffer__new_raw_deprecated(map_fd, page_cnt, opts)
1376 
1377 LIBBPF_API void perf_buffer__free(struct perf_buffer *pb);
1378 LIBBPF_API int perf_buffer__epoll_fd(const struct perf_buffer *pb);
1379 LIBBPF_API int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms);
1380 LIBBPF_API int perf_buffer__consume(struct perf_buffer *pb);
1381 LIBBPF_API int perf_buffer__consume_buffer(struct perf_buffer *pb, size_t buf_idx);
1382 LIBBPF_API size_t perf_buffer__buffer_cnt(const struct perf_buffer *pb);
1383 LIBBPF_API int perf_buffer__buffer_fd(const struct perf_buffer *pb, size_t buf_idx);
1384 
1385 typedef enum bpf_perf_event_ret
1386 	(*bpf_perf_event_print_t)(struct perf_event_header *hdr,
1387 				  void *private_data);
1388 LIBBPF_DEPRECATED_SINCE(0, 8, "use perf_buffer__poll() or  perf_buffer__consume() instead")
1389 LIBBPF_API enum bpf_perf_event_ret
1390 bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size,
1391 			   void **copy_mem, size_t *copy_size,
1392 			   bpf_perf_event_print_t fn, void *private_data);
1393 
1394 struct bpf_prog_linfo;
1395 struct bpf_prog_info;
1396 
1397 LIBBPF_API void bpf_prog_linfo__free(struct bpf_prog_linfo *prog_linfo);
1398 LIBBPF_API struct bpf_prog_linfo *
1399 bpf_prog_linfo__new(const struct bpf_prog_info *info);
1400 LIBBPF_API const struct bpf_line_info *
1401 bpf_prog_linfo__lfind_addr_func(const struct bpf_prog_linfo *prog_linfo,
1402 				__u64 addr, __u32 func_idx, __u32 nr_skip);
1403 LIBBPF_API const struct bpf_line_info *
1404 bpf_prog_linfo__lfind(const struct bpf_prog_linfo *prog_linfo,
1405 		      __u32 insn_off, __u32 nr_skip);
1406 
1407 /*
1408  * Probe for supported system features
1409  *
1410  * Note that running many of these probes in a short amount of time can cause
1411  * the kernel to reach the maximal size of lockable memory allowed for the
1412  * user, causing subsequent probes to fail. In this case, the caller may want
1413  * to adjust that limit with setrlimit().
1414  */
1415 LIBBPF_DEPRECATED_SINCE(0, 8, "use libbpf_probe_bpf_prog_type() instead")
1416 LIBBPF_API bool bpf_probe_prog_type(enum bpf_prog_type prog_type, __u32 ifindex);
1417 LIBBPF_DEPRECATED_SINCE(0, 8, "use libbpf_probe_bpf_map_type() instead")
1418 LIBBPF_API bool bpf_probe_map_type(enum bpf_map_type map_type, __u32 ifindex);
1419 LIBBPF_DEPRECATED_SINCE(0, 8, "use libbpf_probe_bpf_helper() instead")
1420 LIBBPF_API bool bpf_probe_helper(enum bpf_func_id id, enum bpf_prog_type prog_type, __u32 ifindex);
1421 LIBBPF_DEPRECATED_SINCE(0, 8, "implement your own or use bpftool for feature detection")
1422 LIBBPF_API bool bpf_probe_large_insn_limit(__u32 ifindex);
1423 
1424 /**
1425  * @brief **libbpf_probe_bpf_prog_type()** detects if host kernel supports
1426  * BPF programs of a given type.
1427  * @param prog_type BPF program type to detect kernel support for
1428  * @param opts reserved for future extensibility, should be NULL
1429  * @return 1, if given program type is supported; 0, if given program type is
1430  * not supported; negative error code if feature detection failed or can't be
1431  * performed
1432  *
1433  * Make sure the process has required set of CAP_* permissions (or runs as
1434  * root) when performing feature checking.
1435  */
1436 LIBBPF_API int libbpf_probe_bpf_prog_type(enum bpf_prog_type prog_type, const void *opts);
1437 /**
1438  * @brief **libbpf_probe_bpf_map_type()** detects if host kernel supports
1439  * BPF maps of a given type.
1440  * @param map_type BPF map type to detect kernel support for
1441  * @param opts reserved for future extensibility, should be NULL
1442  * @return 1, if given map type is supported; 0, if given map type is
1443  * not supported; negative error code if feature detection failed or can't be
1444  * performed
1445  *
1446  * Make sure the process has required set of CAP_* permissions (or runs as
1447  * root) when performing feature checking.
1448  */
1449 LIBBPF_API int libbpf_probe_bpf_map_type(enum bpf_map_type map_type, const void *opts);
1450 /**
1451  * @brief **libbpf_probe_bpf_helper()** detects if host kernel supports the
1452  * use of a given BPF helper from specified BPF program type.
1453  * @param prog_type BPF program type used to check the support of BPF helper
1454  * @param helper_id BPF helper ID (enum bpf_func_id) to check support for
1455  * @param opts reserved for future extensibility, should be NULL
1456  * @return 1, if given combination of program type and helper is supported; 0,
1457  * if the combination is not supported; negative error code if feature
1458  * detection for provided input arguments failed or can't be performed
1459  *
1460  * Make sure the process has required set of CAP_* permissions (or runs as
1461  * root) when performing feature checking.
1462  */
1463 LIBBPF_API int libbpf_probe_bpf_helper(enum bpf_prog_type prog_type,
1464 				       enum bpf_func_id helper_id, const void *opts);
1465 
1466 /*
1467  * Get bpf_prog_info in continuous memory
1468  *
1469  * struct bpf_prog_info has multiple arrays. The user has option to choose
1470  * arrays to fetch from kernel. The following APIs provide an uniform way to
1471  * fetch these data. All arrays in bpf_prog_info are stored in a single
1472  * continuous memory region. This makes it easy to store the info in a
1473  * file.
1474  *
1475  * Before writing bpf_prog_info_linear to files, it is necessary to
1476  * translate pointers in bpf_prog_info to offsets. Helper functions
1477  * bpf_program__bpil_addr_to_offs() and bpf_program__bpil_offs_to_addr()
1478  * are introduced to switch between pointers and offsets.
1479  *
1480  * Examples:
1481  *   # To fetch map_ids and prog_tags:
1482  *   __u64 arrays = (1UL << BPF_PROG_INFO_MAP_IDS) |
1483  *           (1UL << BPF_PROG_INFO_PROG_TAGS);
1484  *   struct bpf_prog_info_linear *info_linear =
1485  *           bpf_program__get_prog_info_linear(fd, arrays);
1486  *
1487  *   # To save data in file
1488  *   bpf_program__bpil_addr_to_offs(info_linear);
1489  *   write(f, info_linear, sizeof(*info_linear) + info_linear->data_len);
1490  *
1491  *   # To read data from file
1492  *   read(f, info_linear, <proper_size>);
1493  *   bpf_program__bpil_offs_to_addr(info_linear);
1494  */
1495 enum bpf_prog_info_array {
1496 	BPF_PROG_INFO_FIRST_ARRAY = 0,
1497 	BPF_PROG_INFO_JITED_INSNS = 0,
1498 	BPF_PROG_INFO_XLATED_INSNS,
1499 	BPF_PROG_INFO_MAP_IDS,
1500 	BPF_PROG_INFO_JITED_KSYMS,
1501 	BPF_PROG_INFO_JITED_FUNC_LENS,
1502 	BPF_PROG_INFO_FUNC_INFO,
1503 	BPF_PROG_INFO_LINE_INFO,
1504 	BPF_PROG_INFO_JITED_LINE_INFO,
1505 	BPF_PROG_INFO_PROG_TAGS,
1506 	BPF_PROG_INFO_LAST_ARRAY,
1507 };
1508 
1509 struct bpf_prog_info_linear {
1510 	/* size of struct bpf_prog_info, when the tool is compiled */
1511 	__u32			info_len;
1512 	/* total bytes allocated for data, round up to 8 bytes */
1513 	__u32			data_len;
1514 	/* which arrays are included in data */
1515 	__u64			arrays;
1516 	struct bpf_prog_info	info;
1517 	__u8			data[];
1518 };
1519 
1520 LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
1521 LIBBPF_API struct bpf_prog_info_linear *
1522 bpf_program__get_prog_info_linear(int fd, __u64 arrays);
1523 
1524 LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
1525 LIBBPF_API void
1526 bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear);
1527 
1528 LIBBPF_DEPRECATED_SINCE(0, 6, "use a custom linear prog_info wrapper")
1529 LIBBPF_API void
1530 bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear);
1531 
1532 /**
1533  * @brief **libbpf_num_possible_cpus()** is a helper function to get the
1534  * number of possible CPUs that the host kernel supports and expects.
1535  * @return number of possible CPUs; or error code on failure
1536  *
1537  * Example usage:
1538  *
1539  *     int ncpus = libbpf_num_possible_cpus();
1540  *     if (ncpus < 0) {
1541  *          // error handling
1542  *     }
1543  *     long values[ncpus];
1544  *     bpf_map_lookup_elem(per_cpu_map_fd, key, values);
1545  */
1546 LIBBPF_API int libbpf_num_possible_cpus(void);
1547 
1548 struct bpf_map_skeleton {
1549 	const char *name;
1550 	struct bpf_map **map;
1551 	void **mmaped;
1552 };
1553 
1554 struct bpf_prog_skeleton {
1555 	const char *name;
1556 	struct bpf_program **prog;
1557 	struct bpf_link **link;
1558 };
1559 
1560 struct bpf_object_skeleton {
1561 	size_t sz; /* size of this struct, for forward/backward compatibility */
1562 
1563 	const char *name;
1564 	const void *data;
1565 	size_t data_sz;
1566 
1567 	struct bpf_object **obj;
1568 
1569 	int map_cnt;
1570 	int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */
1571 	struct bpf_map_skeleton *maps;
1572 
1573 	int prog_cnt;
1574 	int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */
1575 	struct bpf_prog_skeleton *progs;
1576 };
1577 
1578 LIBBPF_API int
1579 bpf_object__open_skeleton(struct bpf_object_skeleton *s,
1580 			  const struct bpf_object_open_opts *opts);
1581 LIBBPF_API int bpf_object__load_skeleton(struct bpf_object_skeleton *s);
1582 LIBBPF_API int bpf_object__attach_skeleton(struct bpf_object_skeleton *s);
1583 LIBBPF_API void bpf_object__detach_skeleton(struct bpf_object_skeleton *s);
1584 LIBBPF_API void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s);
1585 
1586 struct bpf_var_skeleton {
1587 	const char *name;
1588 	struct bpf_map **map;
1589 	void **addr;
1590 };
1591 
1592 struct bpf_object_subskeleton {
1593 	size_t sz; /* size of this struct, for forward/backward compatibility */
1594 
1595 	const struct bpf_object *obj;
1596 
1597 	int map_cnt;
1598 	int map_skel_sz; /* sizeof(struct bpf_map_skeleton) */
1599 	struct bpf_map_skeleton *maps;
1600 
1601 	int prog_cnt;
1602 	int prog_skel_sz; /* sizeof(struct bpf_prog_skeleton) */
1603 	struct bpf_prog_skeleton *progs;
1604 
1605 	int var_cnt;
1606 	int var_skel_sz; /* sizeof(struct bpf_var_skeleton) */
1607 	struct bpf_var_skeleton *vars;
1608 };
1609 
1610 LIBBPF_API int
1611 bpf_object__open_subskeleton(struct bpf_object_subskeleton *s);
1612 LIBBPF_API void
1613 bpf_object__destroy_subskeleton(struct bpf_object_subskeleton *s);
1614 
1615 struct gen_loader_opts {
1616 	size_t sz; /* size of this struct, for forward/backward compatiblity */
1617 	const char *data;
1618 	const char *insns;
1619 	__u32 data_sz;
1620 	__u32 insns_sz;
1621 };
1622 
1623 #define gen_loader_opts__last_field insns_sz
1624 LIBBPF_API int bpf_object__gen_loader(struct bpf_object *obj,
1625 				      struct gen_loader_opts *opts);
1626 
1627 enum libbpf_tristate {
1628 	TRI_NO = 0,
1629 	TRI_YES = 1,
1630 	TRI_MODULE = 2,
1631 };
1632 
1633 struct bpf_linker_opts {
1634 	/* size of this struct, for forward/backward compatiblity */
1635 	size_t sz;
1636 };
1637 #define bpf_linker_opts__last_field sz
1638 
1639 struct bpf_linker_file_opts {
1640 	/* size of this struct, for forward/backward compatiblity */
1641 	size_t sz;
1642 };
1643 #define bpf_linker_file_opts__last_field sz
1644 
1645 struct bpf_linker;
1646 
1647 LIBBPF_API struct bpf_linker *bpf_linker__new(const char *filename, struct bpf_linker_opts *opts);
1648 LIBBPF_API int bpf_linker__add_file(struct bpf_linker *linker,
1649 				    const char *filename,
1650 				    const struct bpf_linker_file_opts *opts);
1651 LIBBPF_API int bpf_linker__finalize(struct bpf_linker *linker);
1652 LIBBPF_API void bpf_linker__free(struct bpf_linker *linker);
1653 
1654 /*
1655  * Custom handling of BPF program's SEC() definitions
1656  */
1657 
1658 struct bpf_prog_load_opts; /* defined in bpf.h */
1659 
1660 /* Called during bpf_object__open() for each recognized BPF program. Callback
1661  * can use various bpf_program__set_*() setters to adjust whatever properties
1662  * are necessary.
1663  */
1664 typedef int (*libbpf_prog_setup_fn_t)(struct bpf_program *prog, long cookie);
1665 
1666 /* Called right before libbpf performs bpf_prog_load() to load BPF program
1667  * into the kernel. Callback can adjust opts as necessary.
1668  */
1669 typedef int (*libbpf_prog_prepare_load_fn_t)(struct bpf_program *prog,
1670 					     struct bpf_prog_load_opts *opts, long cookie);
1671 
1672 /* Called during skeleton attach or through bpf_program__attach(). If
1673  * auto-attach is not supported, callback should return 0 and set link to
1674  * NULL (it's not considered an error during skeleton attach, but it will be
1675  * an error for bpf_program__attach() calls). On error, error should be
1676  * returned directly and link set to NULL. On success, return 0 and set link
1677  * to a valid struct bpf_link.
1678  */
1679 typedef int (*libbpf_prog_attach_fn_t)(const struct bpf_program *prog, long cookie,
1680 				       struct bpf_link **link);
1681 
1682 struct libbpf_prog_handler_opts {
1683 	/* size of this struct, for forward/backward compatiblity */
1684 	size_t sz;
1685 	/* User-provided value that is passed to prog_setup_fn,
1686 	 * prog_prepare_load_fn, and prog_attach_fn callbacks. Allows user to
1687 	 * register one set of callbacks for multiple SEC() definitions and
1688 	 * still be able to distinguish them, if necessary. For example,
1689 	 * libbpf itself is using this to pass necessary flags (e.g.,
1690 	 * sleepable flag) to a common internal SEC() handler.
1691 	 */
1692 	long cookie;
1693 	/* BPF program initialization callback (see libbpf_prog_setup_fn_t).
1694 	 * Callback is optional, pass NULL if it's not necessary.
1695 	 */
1696 	libbpf_prog_setup_fn_t prog_setup_fn;
1697 	/* BPF program loading callback (see libbpf_prog_prepare_load_fn_t).
1698 	 * Callback is optional, pass NULL if it's not necessary.
1699 	 */
1700 	libbpf_prog_prepare_load_fn_t prog_prepare_load_fn;
1701 	/* BPF program attach callback (see libbpf_prog_attach_fn_t).
1702 	 * Callback is optional, pass NULL if it's not necessary.
1703 	 */
1704 	libbpf_prog_attach_fn_t prog_attach_fn;
1705 };
1706 #define libbpf_prog_handler_opts__last_field prog_attach_fn
1707 
1708 /**
1709  * @brief **libbpf_register_prog_handler()** registers a custom BPF program
1710  * SEC() handler.
1711  * @param sec section prefix for which custom handler is registered
1712  * @param prog_type BPF program type associated with specified section
1713  * @param exp_attach_type Expected BPF attach type associated with specified section
1714  * @param opts optional cookie, callbacks, and other extra options
1715  * @return Non-negative handler ID is returned on success. This handler ID has
1716  * to be passed to *libbpf_unregister_prog_handler()* to unregister such
1717  * custom handler. Negative error code is returned on error.
1718  *
1719  * *sec* defines which SEC() definitions are handled by this custom handler
1720  * registration. *sec* can have few different forms:
1721  *   - if *sec* is just a plain string (e.g., "abc"), it will match only
1722  *   SEC("abc"). If BPF program specifies SEC("abc/whatever") it will result
1723  *   in an error;
1724  *   - if *sec* is of the form "abc/", proper SEC() form is
1725  *   SEC("abc/something"), where acceptable "something" should be checked by
1726  *   *prog_init_fn* callback, if there are additional restrictions;
1727  *   - if *sec* is of the form "abc+", it will successfully match both
1728  *   SEC("abc") and SEC("abc/whatever") forms;
1729  *   - if *sec* is NULL, custom handler is registered for any BPF program that
1730  *   doesn't match any of the registered (custom or libbpf's own) SEC()
1731  *   handlers. There could be only one such generic custom handler registered
1732  *   at any given time.
1733  *
1734  * All custom handlers (except the one with *sec* == NULL) are processed
1735  * before libbpf's own SEC() handlers. It is allowed to "override" libbpf's
1736  * SEC() handlers by registering custom ones for the same section prefix
1737  * (i.e., it's possible to have custom SEC("perf_event/LLC-load-misses")
1738  * handler).
1739  *
1740  * Note, like much of global libbpf APIs (e.g., libbpf_set_print(),
1741  * libbpf_set_strict_mode(), etc)) these APIs are not thread-safe. User needs
1742  * to ensure synchronization if there is a risk of running this API from
1743  * multiple threads simultaneously.
1744  */
1745 LIBBPF_API int libbpf_register_prog_handler(const char *sec,
1746 					    enum bpf_prog_type prog_type,
1747 					    enum bpf_attach_type exp_attach_type,
1748 					    const struct libbpf_prog_handler_opts *opts);
1749 /**
1750  * @brief *libbpf_unregister_prog_handler()* unregisters previously registered
1751  * custom BPF program SEC() handler.
1752  * @param handler_id handler ID returned by *libbpf_register_prog_handler()*
1753  * after successful registration
1754  * @return 0 on success, negative error code if handler isn't found
1755  *
1756  * Note, like much of global libbpf APIs (e.g., libbpf_set_print(),
1757  * libbpf_set_strict_mode(), etc)) these APIs are not thread-safe. User needs
1758  * to ensure synchronization if there is a risk of running this API from
1759  * multiple threads simultaneously.
1760  */
1761 LIBBPF_API int libbpf_unregister_prog_handler(int handler_id);
1762 
1763 #ifdef __cplusplus
1764 } /* extern "C" */
1765 #endif
1766 
1767 #endif /* __LIBBPF_LIBBPF_H */
1768