[lttng-ust.git] / include / lttng / ust-elf.h

/*
 * SPDX-License-Identifier: LGPL-2.1-or-later
 *
 * Copyright (C) 2015 Antoine Busque <abusque@efficios.com>
 */

#ifndef _LTTNG_UST_ELF_H
#define _LTTNG_UST_ELF_H

#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <elf.h>
#include <lttng/ust-endian.h>

/*
 * Determine native endianness in order to convert when reading an ELF
 * file if there is a mismatch.
 */
#if BYTE_ORDER == LITTLE_ENDIAN
#define NATIVE_ELF_ENDIANNESS ELFDATA2LSB
#else
#define NATIVE_ELF_ENDIANNESS ELFDATA2MSB
#endif

/*
 * The size in bytes of the debug link CRC as contained in an ELF
 * section.
 */
#define ELF_CRC_SIZE		4
/*
 * ELF notes are aligned on 4 bytes. ref: ELF specification version
 * 1.1 p. 2-5.
 */
#define ELF_NOTE_ENTRY_ALIGN	4
/*
 * Within an ELF note, the `desc` field is also aligned on 4
 * bytes. ref: ELF specification version 1.1 p. 2-5.
 */
#define ELF_NOTE_DESC_ALIGN	4

#define bswap(x)				\
	do {					\
		switch (sizeof(x)) {		\
		case 8:				\
			x = bswap_64(x);	\
			break;			\
		case 4:				\
			x = bswap_32(x);	\
			break;			\
		case 2:				\
			x = bswap_16(x);	\
			break;			\
		case 1:				\
			break;			\
		default:			\
			abort();		\
		}				\
	} while (0)

#define bswap_phdr(phdr)		\
	do {				\
		bswap((phdr).p_type);	\
		bswap((phdr).p_offset); \
		bswap((phdr).p_filesz); \
		bswap((phdr).p_memsz);	\
		bswap((phdr).p_align);	\
		bswap((phdr).p_vaddr);	\
	} while (0)

#define bswap_shdr(shdr)		    \
	do {				    \
		bswap((shdr).sh_name);	    \
		bswap((shdr).sh_type);	    \
		bswap((shdr).sh_flags);	    \
		bswap((shdr).sh_addr);	    \
		bswap((shdr).sh_offset);    \
		bswap((shdr).sh_size);	    \
		bswap((shdr).sh_link);	    \
		bswap((shdr).sh_info);	    \
		bswap((shdr).sh_addralign); \
		bswap((shdr).sh_entsize);   \
	} while (0)

#define bswap_ehdr(ehdr)				\
	do {						\
		bswap((ehdr).e_type);			\
		bswap((ehdr).e_machine);		\
		bswap((ehdr).e_version);		\
		bswap((ehdr).e_entry);			\
		bswap((ehdr).e_phoff);			\
		bswap((ehdr).e_shoff);			\
		bswap((ehdr).e_flags);			\
		bswap((ehdr).e_ehsize);			\
		bswap((ehdr).e_phentsize);		\
		bswap((ehdr).e_phnum);			\
		bswap((ehdr).e_shentsize);		\
		bswap((ehdr).e_shnum);			\
		bswap((ehdr).e_shstrndx);		\
	} while (0)

#define copy_phdr(src_phdr, dst_phdr)				\
	do {							\
		(dst_phdr).p_type = (src_phdr).p_type;		\
		(dst_phdr).p_offset = (src_phdr).p_offset;	\
		(dst_phdr).p_filesz = (src_phdr).p_filesz;	\
		(dst_phdr).p_memsz = (src_phdr).p_memsz;	\
		(dst_phdr).p_align = (src_phdr).p_align;	\
		(dst_phdr).p_vaddr = (src_phdr).p_vaddr;	\
	} while (0)

#define copy_shdr(src_shdr, dst_shdr)					\
	do {								\
		(dst_shdr).sh_name = (src_shdr).sh_name;		\
		(dst_shdr).sh_type = (src_shdr).sh_type;		\
		(dst_shdr).sh_flags = (src_shdr).sh_flags;		\
		(dst_shdr).sh_addr = (src_shdr).sh_addr;		\
		(dst_shdr).sh_offset = (src_shdr).sh_offset;		\
		(dst_shdr).sh_size = (src_shdr).sh_size;		\
		(dst_shdr).sh_link = (src_shdr).sh_link;		\
		(dst_shdr).sh_info = (src_shdr).sh_info;		\
		(dst_shdr).sh_addralign = (src_shdr).sh_addralign;	\
		(dst_shdr).sh_entsize = (src_shdr).sh_entsize;		\
	} while (0)

#define copy_ehdr(src_ehdr, dst_ehdr)					\
	do {								\
		(dst_ehdr).e_type = (src_ehdr).e_type;			\
		(dst_ehdr).e_machine = (src_ehdr).e_machine;		\
		(dst_ehdr).e_version = (src_ehdr).e_version;		\
		(dst_ehdr).e_entry = (src_ehdr).e_entry;		\
		(dst_ehdr).e_phoff = (src_ehdr).e_phoff;		\
		(dst_ehdr).e_shoff = (src_ehdr).e_shoff;		\
		(dst_ehdr).e_flags = (src_ehdr).e_flags;		\
		(dst_ehdr).e_ehsize = (src_ehdr).e_ehsize;		\
		(dst_ehdr).e_phentsize = (src_ehdr).e_phentsize;	\
		(dst_ehdr).e_phnum = (src_ehdr).e_phnum;		\
		(dst_ehdr).e_shentsize = (src_ehdr).e_shentsize;	\
		(dst_ehdr).e_shnum = (src_ehdr).e_shnum;		\
		(dst_ehdr).e_shstrndx = (src_ehdr).e_shstrndx;		\
	} while (0)

struct lttng_ust_elf_ehdr {
	uint16_t e_type;
	uint16_t e_machine;
	uint32_t e_version;
	uint64_t e_entry;
	uint64_t e_phoff;
	uint64_t e_shoff;
	uint32_t e_flags;
	uint16_t e_ehsize;
	uint16_t e_phentsize;
	uint16_t e_phnum;
	uint16_t e_shentsize;
	uint16_t e_shnum;
	uint16_t e_shstrndx;
};

struct lttng_ust_elf_phdr {
	uint32_t p_type;
	uint64_t p_offset;
	uint64_t p_filesz;
	uint64_t p_memsz;
	uint64_t p_align;
	uint64_t p_vaddr;
};

struct lttng_ust_elf_shdr {
	uint32_t sh_name;
	uint32_t sh_type;
	uint64_t sh_flags;
	uint64_t sh_addr;
	uint64_t sh_offset;
	uint64_t sh_size;
	uint32_t sh_link;
	uint32_t sh_info;
	uint64_t sh_addralign;
	uint64_t sh_entsize;
};

struct lttng_ust_elf_nhdr {
	uint32_t n_namesz;
	uint32_t n_descsz;
	uint32_t n_type;
};

struct lttng_ust_elf {
	/* Offset in bytes to start of section names string table. */
	off_t section_names_offset;
	/* Size in bytes of section names string table. */
	size_t section_names_size;
	char *path;
	int fd;
	struct lttng_ust_elf_ehdr *ehdr;
	uint8_t bitness;
	uint8_t endianness;
};

static inline
int is_elf_32_bit(struct lttng_ust_elf *elf)
{
	return elf->bitness == ELFCLASS32;
}

static inline
int is_elf_native_endian(struct lttng_ust_elf *elf)
{
	return elf->endianness == NATIVE_ELF_ENDIANNESS;
}

struct lttng_ust_elf *lttng_ust_elf_create(const char *path);
void lttng_ust_elf_destroy(struct lttng_ust_elf *elf);
uint8_t lttng_ust_elf_is_pic(struct lttng_ust_elf *elf);
int lttng_ust_elf_get_memsz(struct lttng_ust_elf *elf, uint64_t *memsz);
int lttng_ust_elf_get_build_id(struct lttng_ust_elf *elf, uint8_t **build_id,
			size_t *length, int *found);
int lttng_ust_elf_get_debug_link(struct lttng_ust_elf *elf, char **filename,
			uint32_t *crc, int *found);

#endif	/* _LTTNG_UST_ELF_H */
Commit	Line	Data
8e2aed3f	1	/*
c0c0989a	2	* SPDX-License-Identifier: LGPL-2.1-or-later
8e2aed3f	3	*
c0c0989a	4	* Copyright (C) 2015 Antoine Busque <abusque@efficios.com>
8e2aed3f AB	5	*/
8e2aed3f AB	6
c0c0989a MJ	7	#ifndef _LTTNG_UST_ELF_H
	8	#define _LTTNG_UST_ELF_H
	9
8e2aed3f AB	10	#include <stdlib.h>
	11	#include <stdint.h>
	12	#include <stdio.h>
8e2aed3f AB	13	#include <elf.h>
	14	#include <lttng/ust-endian.h>
	15
	16	/*
	17	* Determine native endianness in order to convert when reading an ELF
	18	* file if there is a mismatch.
	19	*/
	20	#if BYTE_ORDER == LITTLE_ENDIAN
	21	#define NATIVE_ELF_ENDIANNESS ELFDATA2LSB
	22	#else
	23	#define NATIVE_ELF_ENDIANNESS ELFDATA2MSB
	24	#endif
	25
	26	/*
	27	* The size in bytes of the debug link CRC as contained in an ELF
	28	* section.
	29	*/
	30	#define ELF_CRC_SIZE 4
	31	/*
	32	* ELF notes are aligned on 4 bytes. ref: ELF specification version
	33	* 1.1 p. 2-5.
	34	*/
	35	#define ELF_NOTE_ENTRY_ALIGN 4
	36	/*
	37	* Within an ELF note, the `desc` field is also aligned on 4
	38	* bytes. ref: ELF specification version 1.1 p. 2-5.
	39	*/
	40	#define ELF_NOTE_DESC_ALIGN 4
	41
	42	#define bswap(x) \
	43	do { \
	44	switch (sizeof(x)) { \
	45	case 8: \
	46	x = bswap_64(x); \
	47	break; \
	48	case 4: \
	49	x = bswap_32(x); \
	50	break; \
	51	case 2: \
	52	x = bswap_16(x); \
	53	break; \
	54	case 1: \
	55	break; \
	56	default: \
	57	abort(); \
	58	} \
	59	} while (0)
	60
	61	#define bswap_phdr(phdr) \
	62	do { \
	63	bswap((phdr).p_type); \
	64	bswap((phdr).p_offset); \
	65	bswap((phdr).p_filesz); \
	66	bswap((phdr).p_memsz); \
	67	bswap((phdr).p_align); \
e1f0c569	68	bswap((phdr).p_vaddr); \
8e2aed3f AB	69	} while (0)
	70
	71	#define bswap_shdr(shdr) \
	72	do { \
	73	bswap((shdr).sh_name); \
	74	bswap((shdr).sh_type); \
	75	bswap((shdr).sh_flags); \
	76	bswap((shdr).sh_addr); \
	77	bswap((shdr).sh_offset); \
	78	bswap((shdr).sh_size); \
	79	bswap((shdr).sh_link); \
	80	bswap((shdr).sh_info); \
	81	bswap((shdr).sh_addralign); \
	82	bswap((shdr).sh_entsize); \
	83	} while (0)
	84
	85	#define bswap_ehdr(ehdr) \
	86	do { \
	87	bswap((ehdr).e_type); \
	88	bswap((ehdr).e_machine); \
	89	bswap((ehdr).e_version); \
	90	bswap((ehdr).e_entry); \
	91	bswap((ehdr).e_phoff); \
	92	bswap((ehdr).e_shoff); \
	93	bswap((ehdr).e_flags); \
	94	bswap((ehdr).e_ehsize); \
	95	bswap((ehdr).e_phentsize); \
	96	bswap((ehdr).e_phnum); \
	97	bswap((ehdr).e_shentsize); \
	98	bswap((ehdr).e_shnum); \
	99	bswap((ehdr).e_shstrndx); \
	100	} while (0)
	101
	102	#define copy_phdr(src_phdr, dst_phdr) \
	103	do { \
	104	(dst_phdr).p_type = (src_phdr).p_type; \
	105	(dst_phdr).p_offset = (src_phdr).p_offset; \
	106	(dst_phdr).p_filesz = (src_phdr).p_filesz; \
	107	(dst_phdr).p_memsz = (src_phdr).p_memsz; \
	108	(dst_phdr).p_align = (src_phdr).p_align; \
e1f0c569	109	(dst_phdr).p_vaddr = (src_phdr).p_vaddr; \
8e2aed3f AB	110	} while (0)
	111
	112	#define copy_shdr(src_shdr, dst_shdr) \
	113	do { \
	114	(dst_shdr).sh_name = (src_shdr).sh_name; \
	115	(dst_shdr).sh_type = (src_shdr).sh_type; \
	116	(dst_shdr).sh_flags = (src_shdr).sh_flags; \
	117	(dst_shdr).sh_addr = (src_shdr).sh_addr; \
	118	(dst_shdr).sh_offset = (src_shdr).sh_offset; \
	119	(dst_shdr).sh_size = (src_shdr).sh_size; \
	120	(dst_shdr).sh_link = (src_shdr).sh_link; \
	121	(dst_shdr).sh_info = (src_shdr).sh_info; \
	122	(dst_shdr).sh_addralign = (src_shdr).sh_addralign; \
	123	(dst_shdr).sh_entsize = (src_shdr).sh_entsize; \
	124	} while (0)
	125
	126	#define copy_ehdr(src_ehdr, dst_ehdr) \
	127	do { \
	128	(dst_ehdr).e_type = (src_ehdr).e_type; \
	129	(dst_ehdr).e_machine = (src_ehdr).e_machine; \
	130	(dst_ehdr).e_version = (src_ehdr).e_version; \
	131	(dst_ehdr).e_entry = (src_ehdr).e_entry; \
	132	(dst_ehdr).e_phoff = (src_ehdr).e_phoff; \
	133	(dst_ehdr).e_shoff = (src_ehdr).e_shoff; \
	134	(dst_ehdr).e_flags = (src_ehdr).e_flags; \
	135	(dst_ehdr).e_ehsize = (src_ehdr).e_ehsize; \
	136	(dst_ehdr).e_phentsize = (src_ehdr).e_phentsize; \
	137	(dst_ehdr).e_phnum = (src_ehdr).e_phnum; \
	138	(dst_ehdr).e_shentsize = (src_ehdr).e_shentsize; \
	139	(dst_ehdr).e_shnum = (src_ehdr).e_shnum; \
	140	(dst_ehdr).e_shstrndx = (src_ehdr).e_shstrndx; \
	141	} while (0)
	142
	143	struct lttng_ust_elf_ehdr {
	144	uint16_t e_type;
	145	uint16_t e_machine;
	146	uint32_t e_version;
	147	uint64_t e_entry;
	148	uint64_t e_phoff;
	149	uint64_t e_shoff;
	150	uint32_t e_flags;
	151	uint16_t e_ehsize;
	152	uint16_t e_phentsize;
	153	uint16_t e_phnum;
	154	uint16_t e_shentsize;
	155	uint16_t e_shnum;
	156	uint16_t e_shstrndx;
	157	};
	158
	159	struct lttng_ust_elf_phdr {
	160	uint32_t p_type;
	161	uint64_t p_offset;
	162	uint64_t p_filesz;
	163	uint64_t p_memsz;
	164	uint64_t p_align;
e1f0c569	165	uint64_t p_vaddr;
8e2aed3f AB	166	};
	167
	168	struct lttng_ust_elf_shdr {
	169	uint32_t sh_name;
	170	uint32_t sh_type;
	171	uint64_t sh_flags;
	172	uint64_t sh_addr;
	173	uint64_t sh_offset;
	174	uint64_t sh_size;
	175	uint32_t sh_link;
	176	uint32_t sh_info;
	177	uint64_t sh_addralign;
	178	uint64_t sh_entsize;
	179	};
	180
	181	struct lttng_ust_elf_nhdr {
	182	uint32_t n_namesz;
	183	uint32_t n_descsz;
	184	uint32_t n_type;
	185	};
	186
	187	struct lttng_ust_elf {
	188	/* Offset in bytes to start of section names string table. */
f5a6717a	189	off_t section_names_offset;
8e2aed3f	190	/* Size in bytes of section names string table. */
f5a6717a	191	size_t section_names_size;
8e2aed3f	192	char *path;
405be658	193	int fd;
8e2aed3f AB	194	struct lttng_ust_elf_ehdr *ehdr;
	195	uint8_t bitness;
	196	uint8_t endianness;
	197	};
	198
	199	static inline
	200	int is_elf_32_bit(struct lttng_ust_elf *elf)
	201	{
	202	return elf->bitness == ELFCLASS32;
	203	}
	204
	205	static inline
	206	int is_elf_native_endian(struct lttng_ust_elf *elf)
	207	{
	208	return elf->endianness == NATIVE_ELF_ENDIANNESS;
	209	}
	210
	211	struct lttng_ust_elf lttng_ust_elf_create(const char path);
	212	void lttng_ust_elf_destroy(struct lttng_ust_elf *elf);
f5eb039d	213	uint8_t lttng_ust_elf_is_pic(struct lttng_ust_elf *elf);
8e2aed3f AB	214	int lttng_ust_elf_get_memsz(struct lttng_ust_elf elf, uint64_t memsz);
	215	int lttng_ust_elf_get_build_id(struct lttng_ust_elf elf, uint8_t *build_id,
	216	size_t length, int found);
	217	int lttng_ust_elf_get_debug_link(struct lttng_ust_elf elf, char *filename,
	218	uint32_t crc, int found);
	219
	220	#endif /* _LTTNG_UST_ELF_H */