tools/objtool/elf.h

   1 /* SPDX-License-Identifier: GPL-2.0-or-later */
   2 /*
   3  * Copyright (C) 2015 Josh Poimboeuf <jpoimboe@redhat.com>
   4  */
   5
   6 #ifndef _OBJTOOL_ELF_H
   7 #define _OBJTOOL_ELF_H
   8
   9 #include <stdio.h>
  10 #include <gelf.h>
  11 #include <linux/list.h>
  12 #include <linux/hashtable.h>
  13
  14 #ifdef LIBELF_USE_DEPRECATED
  15 # define elf_getshdrnum    elf_getshnum
  16 # define elf_getshdrstrndx elf_getshstrndx
  17 #endif
  18
  19 /*
  20  * Fallback for systems without this "read, mmaping if possible" cmd.
  21  */
  22 #ifndef ELF_C_READ_MMAP
  23 #define ELF_C_READ_MMAP ELF_C_READ
  24 #endif
  25
  26 struct section {
  27         struct list_head list;
  28         GElf_Shdr sh;
  29         struct list_head symbol_list;
  30         DECLARE_HASHTABLE(symbol_hash, 8);
  31         struct list_head rela_list;
  32         DECLARE_HASHTABLE(rela_hash, 16);
  33         struct section *base, *rela;
  34         struct symbol *sym;
  35         Elf_Data *data;
  36         char *name;
  37         int idx;
  38         unsigned int len;
  39         bool changed, text, rodata;
  40 };
  41
  42 struct symbol {
  43         struct list_head list;
  44         struct hlist_node hash;
  45         GElf_Sym sym;
  46         struct section *sec;
  47         char *name;
  48         unsigned int idx;
  49         unsigned char bind, type;
  50         unsigned long offset;
  51         unsigned int len;
  52         struct symbol *pfunc, *cfunc, *alias;
  53         bool uaccess_safe;
  54 };
  55
  56 struct rela {
  57         struct list_head list;
  58         struct hlist_node hash;
  59         GElf_Rela rela;
  60         struct section *sec;
  61         struct symbol *sym;
  62         unsigned int type;
  63         unsigned long offset;
  64         int addend;
  65         bool jump_table_start;
  66 };
  67
  68 struct elf {
  69         Elf *elf;
  70         GElf_Ehdr ehdr;
  71         int fd;
  72         char *name;
  73         struct list_head sections;
  74         DECLARE_HASHTABLE(rela_hash, 16);
  75 };
  76
  77
  78 struct elf *elf_read(const char *name, int flags);
  79 struct section *find_section_by_name(struct elf *elf, const char *name);
  80 struct symbol *find_symbol_by_offset(struct section *sec, unsigned long offset);
  81 struct symbol *find_symbol_by_name(struct elf *elf, const char *name);
  82 struct symbol *find_symbol_containing(struct section *sec, unsigned long offset);
  83 struct rela *find_rela_by_dest(struct section *sec, unsigned long offset);
  84 struct rela *find_rela_by_dest_range(struct section *sec, unsigned long offset,
  85                                      unsigned int len);
  86 struct symbol *find_containing_func(struct section *sec, unsigned long offset);
  87 struct section *elf_create_section(struct elf *elf, const char *name, size_t
  88                                    entsize, int nr);
  89 struct section *elf_create_rela_section(struct elf *elf, struct section *base);
  90 int elf_rebuild_rela_section(struct section *sec);
  91 int elf_write(struct elf *elf);
  92 void elf_close(struct elf *elf);
  93
  94 #define for_each_sec(file, sec)                                         \
  95         list_for_each_entry(sec, &file->elf->sections, list)
  96
  97 #endif /* _OBJTOOL_ELF_H */