ltrace-elf.h revision b5f80ac8982c40f79915ce1e1cb9bf8650ac5fe7 
1#ifndef LTRACE_ELF_H
2#define LTRACE_ELF_H
3
4#include <gelf.h>
5#include <stdlib.h>
6#include "sysdep.h"
7
8struct Process;
9struct library;
10
11/* XXX Ok, the original idea was to separate the low-level ELF data
12 * from the abstract "struct library" object, but we use some of the
13 * following extensively in the back end.  Not all though.  So what we
14 * use should be move to struct library, and the rest of this
15 * structure maybe could be safely hidden in .c.  How to integrate the
16 * arch-specific bits into struct library is unclear as of now.  */
17struct ltelf {
18	int fd;
19	Elf *elf;
20	GElf_Ehdr ehdr;
21	Elf_Data *dynsym;
22	size_t dynsym_count;
23	const char *dynstr;
24	GElf_Addr plt_addr;
25	size_t plt_size;
26	Elf_Data *relplt;
27	Elf_Data *plt_data;
28	size_t relplt_count;
29	Elf_Data *symtab;
30	const char *strtab;
31	const char *soname;
32	size_t symtab_count;
33	Elf_Data *opd;
34	GElf_Addr *opd_addr;
35	size_t opd_size;
36	int lte_flags;
37	GElf_Addr dyn_addr;
38	size_t dyn_sz;
39	size_t relplt_size;
40	GElf_Addr bias;
41	GElf_Addr entry_addr;
42	GElf_Addr base_addr;
43	struct arch_ltelf_data arch;
44};
45
46#define LTE_PLT_EXECUTABLE 2
47
48#define PLTS_ARE_EXECUTABLE(lte) (((lte)->lte_flags & LTE_PLT_EXECUTABLE) != 0)
49
50int open_elf(struct ltelf *lte, const char *filename);
51
52/* XXX is it possible to put breakpoints in VDSO and VSYSCALL
53 * pseudo-libraries?  For now we assume that all libraries can be
54 * opened via a filesystem.  BASE is ignored for ET_EXEC files.  */
55int ltelf_read_library(struct library *lib, struct Process *proc,
56		       const char *filename, GElf_Addr bias);
57
58/* Create a library object representing the main binary.  The entry
59 * point address is stored to *ENTRYP.  */
60struct library *ltelf_read_main_binary(struct Process *proc, const char *path);
61
62GElf_Addr arch_plt_sym_val(struct ltelf *, size_t, GElf_Rela *);
63
64Elf_Data *elf_loaddata(Elf_Scn *scn, GElf_Shdr *shdr);
65int elf_get_section_covering(struct ltelf *lte, GElf_Addr addr,
66			     Elf_Scn **tgt_sec, GElf_Shdr *tgt_shdr);
67int elf_get_section_type(struct ltelf *lte, GElf_Word type,
68			 Elf_Scn **tgt_sec, GElf_Shdr *tgt_shdr);
69
70/* Read, respectively, 2, 4, or 8 bytes from Elf data at given OFFSET,
71 * and store it in *RETP.  Returns 0 on success or a negative value if
72 * there's not enough data.  */
73int elf_read_u16(Elf_Data *data, size_t offset, uint16_t *retp);
74int elf_read_u32(Elf_Data *data, size_t offset, uint32_t *retp);
75int elf_read_u64(Elf_Data *data, size_t offset, uint64_t *retp);
76
77
78#if __WORDSIZE == 32
79#define PRI_ELF_ADDR		PRIx32
80#define GELF_ADDR_CAST(x)	(void *)(uint32_t)(x)
81#else
82#define PRI_ELF_ADDR		PRIx64
83#define GELF_ADDR_CAST(x)	(void *)(x)
84#endif
85
86#endif
87