1 /* SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) */
2 
3 /*
4  * Internal libbpf helpers.
5  *
6  * Copyright (c) 2019 Facebook
7  */
8 
9 #ifndef __LIBBPF_LIBBPF_INTERNAL_H
10 #define __LIBBPF_LIBBPF_INTERNAL_H
11 
12 #include <stdlib.h>
13 #include <limits.h>
14 #include <errno.h>
15 #include <linux/err.h>
16 #include <fcntl.h>
17 #include <unistd.h>
18 #include <libelf.h>
19 #include "relo_core.h"
20 
21 /* make sure libbpf doesn't use kernel-only integer typedefs */
22 #pragma GCC poison u8 u16 u32 u64 s8 s16 s32 s64
23 
24 /* prevent accidental re-addition of reallocarray() */
25 #pragma GCC poison reallocarray
26 
27 #include "libbpf.h"
28 #include "btf.h"
29 
30 #ifndef EM_BPF
31 #define EM_BPF 247
32 #endif
33 
34 #ifndef R_BPF_64_64
35 #define R_BPF_64_64 1
36 #endif
37 #ifndef R_BPF_64_ABS64
38 #define R_BPF_64_ABS64 2
39 #endif
40 #ifndef R_BPF_64_ABS32
41 #define R_BPF_64_ABS32 3
42 #endif
43 #ifndef R_BPF_64_32
44 #define R_BPF_64_32 10
45 #endif
46 
47 #ifndef SHT_LLVM_ADDRSIG
48 #define SHT_LLVM_ADDRSIG 0x6FFF4C03
49 #endif
50 
51 /* if libelf is old and doesn't support mmap(), fall back to read() */
52 #ifndef ELF_C_READ_MMAP
53 #define ELF_C_READ_MMAP ELF_C_READ
54 #endif
55 
56 /* Older libelf all end up in this expression, for both 32 and 64 bit */
57 #ifndef ELF64_ST_VISIBILITY
58 #define ELF64_ST_VISIBILITY(o) ((o) & 0x03)
59 #endif
60 
61 #define BTF_INFO_ENC(kind, kind_flag, vlen) \
62 	((!!(kind_flag) << 31) | ((kind) << 24) | ((vlen) & BTF_MAX_VLEN))
63 #define BTF_TYPE_ENC(name, info, size_or_type) (name), (info), (size_or_type)
64 #define BTF_INT_ENC(encoding, bits_offset, nr_bits) \
65 	((encoding) << 24 | (bits_offset) << 16 | (nr_bits))
66 #define BTF_TYPE_INT_ENC(name, encoding, bits_offset, bits, sz) \
67 	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_INT, 0, 0), sz), \
68 	BTF_INT_ENC(encoding, bits_offset, bits)
69 #define BTF_MEMBER_ENC(name, type, bits_offset) (name), (type), (bits_offset)
70 #define BTF_PARAM_ENC(name, type) (name), (type)
71 #define BTF_VAR_SECINFO_ENC(type, offset, size) (type), (offset), (size)
72 #define BTF_TYPE_FLOAT_ENC(name, sz) \
73 	BTF_TYPE_ENC(name, BTF_INFO_ENC(BTF_KIND_FLOAT, 0, 0), sz)
74 #define BTF_TYPE_DECL_TAG_ENC(value, type, component_idx) \
75 	BTF_TYPE_ENC(value, BTF_INFO_ENC(BTF_KIND_DECL_TAG, 0, 0), type), (component_idx)
76 #define BTF_TYPE_TYPE_TAG_ENC(value, type) \
77 	BTF_TYPE_ENC(value, BTF_INFO_ENC(BTF_KIND_TYPE_TAG, 0, 0), type)
78 
79 #ifndef likely
80 #define likely(x) __builtin_expect(!!(x), 1)
81 #endif
82 #ifndef unlikely
83 #define unlikely(x) __builtin_expect(!!(x), 0)
84 #endif
85 #ifndef min
86 # define min(x, y) ((x) < (y) ? (x) : (y))
87 #endif
88 #ifndef max
89 # define max(x, y) ((x) < (y) ? (y) : (x))
90 #endif
91 #ifndef offsetofend
92 # define offsetofend(TYPE, FIELD) \
93 	(offsetof(TYPE, FIELD) + sizeof(((TYPE *)0)->FIELD))
94 #endif
95 #ifndef __alias
96 #define __alias(symbol) __attribute__((alias(#symbol)))
97 #endif
98 
99 /* Check whether a string `str` has prefix `pfx`, regardless if `pfx` is
100  * a string literal known at compilation time or char * pointer known only at
101  * runtime.
102  */
103 #define str_has_pfx(str, pfx) \
104 	(strncmp(str, pfx, __builtin_constant_p(pfx) ? sizeof(pfx) - 1 : strlen(pfx)) == 0)
105 
106 /* suffix check */
str_has_sfx(const char * str,const char * sfx)107 static inline bool str_has_sfx(const char *str, const char *sfx)
108 {
109 	size_t str_len = strlen(str);
110 	size_t sfx_len = strlen(sfx);
111 
112 	if (sfx_len > str_len)
113 		return false;
114 	return strcmp(str + str_len - sfx_len, sfx) == 0;
115 }
116 
117 /* Symbol versioning is different between static and shared library.
118  * Properly versioned symbols are needed for shared library, but
119  * only the symbol of the new version is needed for static library.
120  * Starting with GNU C 10, use symver attribute instead of .symver assembler
121  * directive, which works better with GCC LTO builds.
122  */
123 #if defined(SHARED) && defined(__GNUC__) && __GNUC__ >= 10
124 
125 #define DEFAULT_VERSION(internal_name, api_name, version) \
126 	__attribute__((symver(#api_name "@@" #version)))
127 #define COMPAT_VERSION(internal_name, api_name, version) \
128 	__attribute__((symver(#api_name "@" #version)))
129 
130 #elif defined(SHARED)
131 
132 #define COMPAT_VERSION(internal_name, api_name, version) \
133 	asm(".symver " #internal_name "," #api_name "@" #version);
134 #define DEFAULT_VERSION(internal_name, api_name, version) \
135 	asm(".symver " #internal_name "," #api_name "@@" #version);
136 
137 #else /* !SHARED */
138 
139 #define COMPAT_VERSION(internal_name, api_name, version)
140 #define DEFAULT_VERSION(internal_name, api_name, version) \
141 	extern typeof(internal_name) api_name \
142 	__attribute__((alias(#internal_name)));
143 
144 #endif
145 
146 extern void libbpf_print(enum libbpf_print_level level,
147 			 const char *format, ...)
148 	__attribute__((format(printf, 2, 3)));
149 
150 #define __pr(level, fmt, ...)	\
151 do {				\
152 	libbpf_print(level, "libbpf: " fmt, ##__VA_ARGS__);	\
153 } while (0)
154 
155 #define pr_warn(fmt, ...)	__pr(LIBBPF_WARN, fmt, ##__VA_ARGS__)
156 #define pr_info(fmt, ...)	__pr(LIBBPF_INFO, fmt, ##__VA_ARGS__)
157 #define pr_debug(fmt, ...)	__pr(LIBBPF_DEBUG, fmt, ##__VA_ARGS__)
158 
159 #ifndef __has_builtin
160 #define __has_builtin(x) 0
161 #endif
162 
163 struct bpf_link {
164 	int (*detach)(struct bpf_link *link);
165 	void (*dealloc)(struct bpf_link *link);
166 	char *pin_path;		/* NULL, if not pinned */
167 	int fd;			/* hook FD, -1 if not applicable */
168 	bool disconnected;
169 };
170 
171 /*
172  * Re-implement glibc's reallocarray() for libbpf internal-only use.
173  * reallocarray(), unfortunately, is not available in all versions of glibc,
174  * so requires extra feature detection and using reallocarray() stub from
175  * <tools/libc_compat.h> and COMPAT_NEED_REALLOCARRAY. All this complicates
176  * build of libbpf unnecessarily and is just a maintenance burden. Instead,
177  * it's trivial to implement libbpf-specific internal version and use it
178  * throughout libbpf.
179  */
libbpf_reallocarray(void * ptr,size_t nmemb,size_t size)180 static inline void *libbpf_reallocarray(void *ptr, size_t nmemb, size_t size)
181 {
182 	size_t total;
183 
184 #if __has_builtin(__builtin_mul_overflow)
185 	if (unlikely(__builtin_mul_overflow(nmemb, size, &total)))
186 		return NULL;
187 #else
188 	if (size == 0 || nmemb > ULONG_MAX / size)
189 		return NULL;
190 	total = nmemb * size;
191 #endif
192 	return realloc(ptr, total);
193 }
194 
195 /* Copy up to sz - 1 bytes from zero-terminated src string and ensure that dst
196  * is zero-terminated string no matter what (unless sz == 0, in which case
197  * it's a no-op). It's conceptually close to FreeBSD's strlcpy(), but differs
198  * in what is returned. Given this is internal helper, it's trivial to extend
199  * this, when necessary. Use this instead of strncpy inside libbpf source code.
200  */
libbpf_strlcpy(char * dst,const char * src,size_t sz)201 static inline void libbpf_strlcpy(char *dst, const char *src, size_t sz)
202 {
203 	size_t i;
204 
205 	if (sz == 0)
206 		return;
207 
208 	sz--;
209 	for (i = 0; i < sz && src[i]; i++)
210 		dst[i] = src[i];
211 	dst[i] = '\0';
212 }
213 
214 __u32 get_kernel_version(void);
215 
216 struct btf;
217 struct btf_type;
218 
219 struct btf_type *btf_type_by_id(const struct btf *btf, __u32 type_id);
220 const char *btf_kind_str(const struct btf_type *t);
221 const struct btf_type *skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id);
222 
btf_func_linkage(const struct btf_type * t)223 static inline enum btf_func_linkage btf_func_linkage(const struct btf_type *t)
224 {
225 	return (enum btf_func_linkage)(int)btf_vlen(t);
226 }
227 
btf_type_info(int kind,int vlen,int kflag)228 static inline __u32 btf_type_info(int kind, int vlen, int kflag)
229 {
230 	return (kflag << 31) | (kind << 24) | vlen;
231 }
232 
233 enum map_def_parts {
234 	MAP_DEF_MAP_TYPE	= 0x001,
235 	MAP_DEF_KEY_TYPE	= 0x002,
236 	MAP_DEF_KEY_SIZE	= 0x004,
237 	MAP_DEF_VALUE_TYPE	= 0x008,
238 	MAP_DEF_VALUE_SIZE	= 0x010,
239 	MAP_DEF_MAX_ENTRIES	= 0x020,
240 	MAP_DEF_MAP_FLAGS	= 0x040,
241 	MAP_DEF_NUMA_NODE	= 0x080,
242 	MAP_DEF_PINNING		= 0x100,
243 	MAP_DEF_INNER_MAP	= 0x200,
244 	MAP_DEF_MAP_EXTRA	= 0x400,
245 
246 	MAP_DEF_ALL		= 0x7ff, /* combination of all above */
247 };
248 
249 struct btf_map_def {
250 	enum map_def_parts parts;
251 	__u32 map_type;
252 	__u32 key_type_id;
253 	__u32 key_size;
254 	__u32 value_type_id;
255 	__u32 value_size;
256 	__u32 max_entries;
257 	__u32 map_flags;
258 	__u32 numa_node;
259 	__u32 pinning;
260 	__u64 map_extra;
261 };
262 
263 int parse_btf_map_def(const char *map_name, struct btf *btf,
264 		      const struct btf_type *def_t, bool strict,
265 		      struct btf_map_def *map_def, struct btf_map_def *inner_def);
266 
267 void *libbpf_add_mem(void **data, size_t *cap_cnt, size_t elem_sz,
268 		     size_t cur_cnt, size_t max_cnt, size_t add_cnt);
269 int libbpf_ensure_mem(void **data, size_t *cap_cnt, size_t elem_sz, size_t need_cnt);
270 
libbpf_is_mem_zeroed(const char * p,ssize_t len)271 static inline bool libbpf_is_mem_zeroed(const char *p, ssize_t len)
272 {
273 	while (len > 0) {
274 		if (*p)
275 			return false;
276 		p++;
277 		len--;
278 	}
279 	return true;
280 }
281 
libbpf_validate_opts(const char * opts,size_t opts_sz,size_t user_sz,const char * type_name)282 static inline bool libbpf_validate_opts(const char *opts,
283 					size_t opts_sz, size_t user_sz,
284 					const char *type_name)
285 {
286 	if (user_sz < sizeof(size_t)) {
287 		pr_warn("%s size (%zu) is too small\n", type_name, user_sz);
288 		return false;
289 	}
290 	if (!libbpf_is_mem_zeroed(opts + opts_sz, (ssize_t)user_sz - opts_sz)) {
291 		pr_warn("%s has non-zero extra bytes\n", type_name);
292 		return false;
293 	}
294 	return true;
295 }
296 
297 #define OPTS_VALID(opts, type)						      \
298 	(!(opts) || libbpf_validate_opts((const char *)opts,		      \
299 					 offsetofend(struct type,	      \
300 						     type##__last_field),     \
301 					 (opts)->sz, #type))
302 #define OPTS_HAS(opts, field) \
303 	((opts) && opts->sz >= offsetofend(typeof(*(opts)), field))
304 #define OPTS_GET(opts, field, fallback_value) \
305 	(OPTS_HAS(opts, field) ? (opts)->field : fallback_value)
306 #define OPTS_SET(opts, field, value)		\
307 	do {					\
308 		if (OPTS_HAS(opts, field))	\
309 			(opts)->field = value;	\
310 	} while (0)
311 
312 #define OPTS_ZEROED(opts, last_nonzero_field)				      \
313 ({									      \
314 	ssize_t __off = offsetofend(typeof(*(opts)), last_nonzero_field);     \
315 	!(opts) || libbpf_is_mem_zeroed((const void *)opts + __off,	      \
316 					(opts)->sz - __off);		      \
317 })
318 
319 enum kern_feature_id {
320 	/* v4.14: kernel support for program & map names. */
321 	FEAT_PROG_NAME,
322 	/* v5.2: kernel support for global data sections. */
323 	FEAT_GLOBAL_DATA,
324 	/* BTF support */
325 	FEAT_BTF,
326 	/* BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO support */
327 	FEAT_BTF_FUNC,
328 	/* BTF_KIND_VAR and BTF_KIND_DATASEC support */
329 	FEAT_BTF_DATASEC,
330 	/* BTF_FUNC_GLOBAL is supported */
331 	FEAT_BTF_GLOBAL_FUNC,
332 	/* BPF_F_MMAPABLE is supported for arrays */
333 	FEAT_ARRAY_MMAP,
334 	/* kernel support for expected_attach_type in BPF_PROG_LOAD */
335 	FEAT_EXP_ATTACH_TYPE,
336 	/* bpf_probe_read_{kernel,user}[_str] helpers */
337 	FEAT_PROBE_READ_KERN,
338 	/* BPF_PROG_BIND_MAP is supported */
339 	FEAT_PROG_BIND_MAP,
340 	/* Kernel support for module BTFs */
341 	FEAT_MODULE_BTF,
342 	/* BTF_KIND_FLOAT support */
343 	FEAT_BTF_FLOAT,
344 	/* BPF perf link support */
345 	FEAT_PERF_LINK,
346 	/* BTF_KIND_DECL_TAG support */
347 	FEAT_BTF_DECL_TAG,
348 	/* BTF_KIND_TYPE_TAG support */
349 	FEAT_BTF_TYPE_TAG,
350 	/* memcg-based accounting for BPF maps and progs */
351 	FEAT_MEMCG_ACCOUNT,
352 	/* BPF cookie (bpf_get_attach_cookie() BPF helper) support */
353 	FEAT_BPF_COOKIE,
354 	/* BTF_KIND_ENUM64 support and BTF_KIND_ENUM kflag support */
355 	FEAT_BTF_ENUM64,
356 	/* Kernel uses syscall wrapper (CONFIG_ARCH_HAS_SYSCALL_WRAPPER) */
357 	FEAT_SYSCALL_WRAPPER,
358 	/* BPF multi-uprobe link support */
359 	FEAT_UPROBE_MULTI_LINK,
360 	__FEAT_CNT,
361 };
362 
363 int probe_memcg_account(void);
364 bool kernel_supports(const struct bpf_object *obj, enum kern_feature_id feat_id);
365 int bump_rlimit_memlock(void);
366 
367 int parse_cpu_mask_str(const char *s, bool **mask, int *mask_sz);
368 int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz);
369 int libbpf__load_raw_btf(const char *raw_types, size_t types_len,
370 			 const char *str_sec, size_t str_len);
371 int btf_load_into_kernel(struct btf *btf, char *log_buf, size_t log_sz, __u32 log_level);
372 
373 struct btf *btf_get_from_fd(int btf_fd, struct btf *base_btf);
374 void btf_get_kernel_prefix_kind(enum bpf_attach_type attach_type,
375 				const char **prefix, int *kind);
376 
377 struct btf_ext_info {
378 	/*
379 	 * info points to the individual info section (e.g. func_info and
380 	 * line_info) from the .BTF.ext. It does not include the __u32 rec_size.
381 	 */
382 	void *info;
383 	__u32 rec_size;
384 	__u32 len;
385 	/* optional (maintained internally by libbpf) mapping between .BTF.ext
386 	 * section and corresponding ELF section. This is used to join
387 	 * information like CO-RE relocation records with corresponding BPF
388 	 * programs defined in ELF sections
389 	 */
390 	__u32 *sec_idxs;
391 	int sec_cnt;
392 };
393 
394 #define for_each_btf_ext_sec(seg, sec)					\
395 	for (sec = (seg)->info;						\
396 	     (void *)sec < (seg)->info + (seg)->len;			\
397 	     sec = (void *)sec + sizeof(struct btf_ext_info_sec) +	\
398 		   (seg)->rec_size * sec->num_info)
399 
400 #define for_each_btf_ext_rec(seg, sec, i, rec)				\
401 	for (i = 0, rec = (void *)&(sec)->data;				\
402 	     i < (sec)->num_info;					\
403 	     i++, rec = (void *)rec + (seg)->rec_size)
404 
405 /*
406  * The .BTF.ext ELF section layout defined as
407  *   struct btf_ext_header
408  *   func_info subsection
409  *
410  * The func_info subsection layout:
411  *   record size for struct bpf_func_info in the func_info subsection
412  *   struct btf_sec_func_info for section #1
413  *   a list of bpf_func_info records for section #1
414  *     where struct bpf_func_info mimics one in include/uapi/linux/bpf.h
415  *     but may not be identical
416  *   struct btf_sec_func_info for section #2
417  *   a list of bpf_func_info records for section #2
418  *   ......
419  *
420  * Note that the bpf_func_info record size in .BTF.ext may not
421  * be the same as the one defined in include/uapi/linux/bpf.h.
422  * The loader should ensure that record_size meets minimum
423  * requirement and pass the record as is to the kernel. The
424  * kernel will handle the func_info properly based on its contents.
425  */
426 struct btf_ext_header {
427 	__u16	magic;
428 	__u8	version;
429 	__u8	flags;
430 	__u32	hdr_len;
431 
432 	/* All offsets are in bytes relative to the end of this header */
433 	__u32	func_info_off;
434 	__u32	func_info_len;
435 	__u32	line_info_off;
436 	__u32	line_info_len;
437 
438 	/* optional part of .BTF.ext header */
439 	__u32	core_relo_off;
440 	__u32	core_relo_len;
441 };
442 
443 struct btf_ext {
444 	union {
445 		struct btf_ext_header *hdr;
446 		void *data;
447 	};
448 	struct btf_ext_info func_info;
449 	struct btf_ext_info line_info;
450 	struct btf_ext_info core_relo_info;
451 	__u32 data_size;
452 };
453 
454 struct btf_ext_info_sec {
455 	__u32	sec_name_off;
456 	__u32	num_info;
457 	/* Followed by num_info * record_size number of bytes */
458 	__u8	data[];
459 };
460 
461 /* The minimum bpf_func_info checked by the loader */
462 struct bpf_func_info_min {
463 	__u32   insn_off;
464 	__u32   type_id;
465 };
466 
467 /* The minimum bpf_line_info checked by the loader */
468 struct bpf_line_info_min {
469 	__u32	insn_off;
470 	__u32	file_name_off;
471 	__u32	line_off;
472 	__u32	line_col;
473 };
474 
475 
476 typedef int (*type_id_visit_fn)(__u32 *type_id, void *ctx);
477 typedef int (*str_off_visit_fn)(__u32 *str_off, void *ctx);
478 int btf_type_visit_type_ids(struct btf_type *t, type_id_visit_fn visit, void *ctx);
479 int btf_type_visit_str_offs(struct btf_type *t, str_off_visit_fn visit, void *ctx);
480 int btf_ext_visit_type_ids(struct btf_ext *btf_ext, type_id_visit_fn visit, void *ctx);
481 int btf_ext_visit_str_offs(struct btf_ext *btf_ext, str_off_visit_fn visit, void *ctx);
482 __s32 btf__find_by_name_kind_own(const struct btf *btf, const char *type_name,
483 				 __u32 kind);
484 
485 typedef int (*kallsyms_cb_t)(unsigned long long sym_addr, char sym_type,
486 			     const char *sym_name, void *ctx);
487 
488 int libbpf_kallsyms_parse(kallsyms_cb_t cb, void *arg);
489 
490 /* handle direct returned errors */
libbpf_err(int ret)491 static inline int libbpf_err(int ret)
492 {
493 	if (ret < 0)
494 		errno = -ret;
495 	return ret;
496 }
497 
498 /* handle errno-based (e.g., syscall or libc) errors according to libbpf's
499  * strict mode settings
500  */
libbpf_err_errno(int ret)501 static inline int libbpf_err_errno(int ret)
502 {
503 	/* errno is already assumed to be set on error */
504 	return ret < 0 ? -errno : ret;
505 }
506 
507 /* handle error for pointer-returning APIs, err is assumed to be < 0 always */
libbpf_err_ptr(int err)508 static inline void *libbpf_err_ptr(int err)
509 {
510 	/* set errno on error, this doesn't break anything */
511 	errno = -err;
512 	return NULL;
513 }
514 
515 /* handle pointer-returning APIs' error handling */
libbpf_ptr(void * ret)516 static inline void *libbpf_ptr(void *ret)
517 {
518 	/* set errno on error, this doesn't break anything */
519 	if (IS_ERR(ret))
520 		errno = -PTR_ERR(ret);
521 
522 	return IS_ERR(ret) ? NULL : ret;
523 }
524 
str_is_empty(const char * s)525 static inline bool str_is_empty(const char *s)
526 {
527 	return !s || !s[0];
528 }
529 
is_ldimm64_insn(struct bpf_insn * insn)530 static inline bool is_ldimm64_insn(struct bpf_insn *insn)
531 {
532 	return insn->code == (BPF_LD | BPF_IMM | BPF_DW);
533 }
534 
535 /* if fd is stdin, stdout, or stderr, dup to a fd greater than 2
536  * Takes ownership of the fd passed in, and closes it if calling
537  * fcntl(fd, F_DUPFD_CLOEXEC, 3).
538  */
ensure_good_fd(int fd)539 static inline int ensure_good_fd(int fd)
540 {
541 	int old_fd = fd, saved_errno;
542 
543 	if (fd < 0)
544 		return fd;
545 	if (fd < 3) {
546 		fd = fcntl(fd, F_DUPFD_CLOEXEC, 3);
547 		saved_errno = errno;
548 		close(old_fd);
549 		errno = saved_errno;
550 		if (fd < 0) {
551 			pr_warn("failed to dup FD %d to FD > 2: %d\n", old_fd, -saved_errno);
552 			errno = saved_errno;
553 		}
554 	}
555 	return fd;
556 }
557 
558 /* The following two functions are exposed to bpftool */
559 int bpf_core_add_cands(struct bpf_core_cand *local_cand,
560 		       size_t local_essent_len,
561 		       const struct btf *targ_btf,
562 		       const char *targ_btf_name,
563 		       int targ_start_id,
564 		       struct bpf_core_cand_list *cands);
565 void bpf_core_free_cands(struct bpf_core_cand_list *cands);
566 
567 struct usdt_manager *usdt_manager_new(struct bpf_object *obj);
568 void usdt_manager_free(struct usdt_manager *man);
569 struct bpf_link * usdt_manager_attach_usdt(struct usdt_manager *man,
570 					   const struct bpf_program *prog,
571 					   pid_t pid, const char *path,
572 					   const char *usdt_provider, const char *usdt_name,
573 					   __u64 usdt_cookie);
574 
is_pow_of_2(size_t x)575 static inline bool is_pow_of_2(size_t x)
576 {
577 	return x && (x & (x - 1)) == 0;
578 }
579 
580 #define PROG_LOAD_ATTEMPTS 5
581 int sys_bpf_prog_load(union bpf_attr *attr, unsigned int size, int attempts);
582 
583 bool glob_match(const char *str, const char *pat);
584 
585 long elf_find_func_offset(Elf *elf, const char *binary_path, const char *name);
586 long elf_find_func_offset_from_file(const char *binary_path, const char *name);
587 
588 struct elf_fd {
589 	Elf *elf;
590 	int fd;
591 };
592 
593 int elf_open(const char *binary_path, struct elf_fd *elf_fd);
594 void elf_close(struct elf_fd *elf_fd);
595 
596 int elf_resolve_syms_offsets(const char *binary_path, int cnt,
597 			     const char **syms, unsigned long **poffsets);
598 int elf_resolve_pattern_offsets(const char *binary_path, const char *pattern,
599 				 unsigned long **poffsets, size_t *pcnt);
600 
601 #endif /* __LIBBPF_LIBBPF_INTERNAL_H */
602