ltrace-elf.h revision 6db61f509eb7537ca64873b0c8c1955e2293db9f
1/* 2 * This file is part of ltrace. 3 * Copyright (C) 2006,2010,2012 Petr Machata, Red Hat Inc. 4 * Copyright (C) 2010 Zachary T Welch 5 * Copyright (C) 2001,2004,2007,2009 Juan Cespedes 6 * Copyright (C) 2006 Ian Wienand 7 * 8 * This program is free software; you can redistribute it and/or 9 * modify it under the terms of the GNU General Public License as 10 * published by the Free Software Foundation; either version 2 of the 11 * License, or (at your option) any later version. 12 * 13 * This program is distributed in the hope that it will be useful, but 14 * WITHOUT ANY WARRANTY; without even the implied warranty of 15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 16 * General Public License for more details. 17 * 18 * You should have received a copy of the GNU General Public License 19 * along with this program; if not, write to the Free Software 20 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 21 * 02110-1301 USA 22 */ 23 24#ifndef LTRACE_ELF_H 25#define LTRACE_ELF_H 26 27#include <gelf.h> 28#include <stdlib.h> 29#include "sysdep.h" 30 31struct Process; 32struct library; 33struct library_symbol; 34 35/* XXX Ok, the original idea was to separate the low-level ELF data 36 * from the abstract "struct library" object, but we use some of the 37 * following extensively in the back end. Not all though. So what we 38 * use should be move to struct library, and the rest of this 39 * structure maybe could be safely hidden in .c. How to integrate the 40 * arch-specific bits into struct library is unclear as of now. */ 41struct ltelf { 42 int fd; 43 Elf *elf; 44 GElf_Ehdr ehdr; 45 Elf_Data *dynsym; 46 size_t dynsym_count; 47 const char *dynstr; 48 GElf_Addr plt_addr; 49 GElf_Word plt_flags; 50 size_t plt_size; 51 Elf_Data *relplt; 52 Elf_Data *plt_data; 53 size_t relplt_count; 54 Elf_Data *symtab; 55 const char *strtab; 56 const char *soname; 57 size_t symtab_count; 58 Elf_Data *opd; 59 GElf_Addr *opd_addr; 60 size_t opd_size; 61 GElf_Addr dyn_addr; 62 size_t dyn_sz; 63 size_t relplt_size; 64 GElf_Addr bias; 65 GElf_Addr entry_addr; 66 GElf_Addr base_addr; 67 struct arch_ltelf_data arch; 68}; 69 70int open_elf(struct ltelf *lte, const char *filename); 71void do_close_elf(struct ltelf *lte); 72 73/* XXX is it possible to put breakpoints in VDSO and VSYSCALL 74 * pseudo-libraries? For now we assume that all libraries can be 75 * opened via a filesystem. BASE is ignored for ET_EXEC files. */ 76int ltelf_read_library(struct library *lib, struct Process *proc, 77 const char *filename, GElf_Addr bias); 78 79/* Create a library object representing the main binary. The entry 80 * point address is stored to *ENTRYP. */ 81struct library *ltelf_read_main_binary(struct Process *proc, const char *path); 82 83/* Create a default PLT entry. This can be used instead (or in 84 * addition to) returning plt_default from arch_elf_add_plt_entry. 85 * RET shall be initialized, the created symbol will be added to the 86 * beginning of the linked list at *RET. This function doesn't add 87 * the symbol to LTE. arch_elf_add_plt_entry has the chance to adjust 88 * symbol internals to its liking, and then return either plt_default 89 * or plt_ok. */ 90int default_elf_add_plt_entry(struct Process *proc, struct ltelf *lte, 91 const char *a_name, GElf_Rela *rela, size_t ndx, 92 struct library_symbol **ret); 93 94/* The base implementation of backend.h (arch_get_sym_info). 95 * See backend.h for details. */ 96int elf_get_sym_info(struct ltelf *lte, const char *filename, 97 size_t sym_index, GElf_Rela *rela, GElf_Sym *sym); 98 99Elf_Data *elf_loaddata(Elf_Scn *scn, GElf_Shdr *shdr); 100int elf_get_section_covering(struct ltelf *lte, GElf_Addr addr, 101 Elf_Scn **tgt_sec, GElf_Shdr *tgt_shdr); 102int elf_get_section_type(struct ltelf *lte, GElf_Word type, 103 Elf_Scn **tgt_sec, GElf_Shdr *tgt_shdr); 104int elf_get_section_named(struct ltelf *lte, const char *name, 105 Elf_Scn **tgt_sec, GElf_Shdr *tgt_shdr); 106 107/* Read, respectively, 2, 4, or 8 bytes from Elf data at given OFFSET, 108 * and store it in *RETP. Returns 0 on success or a negative value if 109 * there's not enough data. */ 110int elf_read_u16(Elf_Data *data, GElf_Xword offset, uint16_t *retp); 111int elf_read_u32(Elf_Data *data, GElf_Xword offset, uint32_t *retp); 112int elf_read_u64(Elf_Data *data, GElf_Xword offset, uint64_t *retp); 113 114#if __WORDSIZE == 32 115#define PRI_ELF_ADDR PRIx32 116#define GELF_ADDR_CAST(x) (void *)(uint32_t)(x) 117#else 118#define PRI_ELF_ADDR PRIx64 119#define GELF_ADDR_CAST(x) (void *)(x) 120#endif 121 122#endif 123