mirror of
https://sourceware.org/git/glibc.git
synced 2025-07-29 11:41:21 +03:00
2.5-18.1
This commit is contained in:
Jakub Jelinek
220
elf/readelflib.c
Normal file
220
elf/readelflib.c
Normal file
@ -0,0 +1,220 @@
|
||||
/* Copyright (C) 1999, 2000, 2001, 2002 Free Software Foundation, Inc.
|
||||
This file is part of the GNU C Library.
|
||||
Contributed by Andreas Jaeger <aj@suse.de>, 1999 and
|
||||
Jakub Jelinek <jakub@redhat.com>, 1999.
|
||||
|
||||
The GNU C Library is free software; you can redistribute it and/or
|
||||
modify it under the terms of the GNU Lesser General Public
|
||||
License as published by the Free Software Foundation; either
|
||||
version 2.1 of the License, or (at your option) any later version.
|
||||
|
||||
The GNU C Library is distributed in the hope that it will be useful,
|
||||
but WITHOUT ANY WARRANTY; without even the implied warranty of
|
||||
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
|
||||
Lesser General Public License for more details.
|
||||
|
||||
You should have received a copy of the GNU Lesser General Public
|
||||
License along with the GNU C Library; if not, write to the Free
|
||||
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
|
||||
02111-1307 USA. */
|
||||
|
||||
/* This code is a heavily simplified version of the readelf program
|
||||
that's part of the current binutils development version. For architectures
|
||||
which need to handle both 32bit and 64bit ELF libraries, this file is
|
||||
included twice for each arch size. */
|
||||
|
||||
/* check_ptr checks that a pointer is in the mmaped file and doesn't
|
||||
point outside it. */
|
||||
#undef check_ptr
|
||||
#define check_ptr(ptr) \
|
||||
do \
|
||||
{ \
|
||||
if ((void *)(ptr) < file_contents \
|
||||
|| (void *)(ptr) > (file_contents+file_length)) \
|
||||
{ \
|
||||
error (0, 0, _("file %s is truncated\n"), file_name); \
|
||||
return 1; \
|
||||
} \
|
||||
} \
|
||||
while (0);
|
||||
|
||||
/* Returns 0 if everything is ok, != 0 in case of error. */
|
||||
int
|
||||
process_elf_file (const char *file_name, const char *lib, int *flag,
|
||||
unsigned int *osversion, char **soname, void *file_contents,
|
||||
size_t file_length)
|
||||
{
|
||||
int i;
|
||||
unsigned int j;
|
||||
ElfW(Addr) loadaddr;
|
||||
unsigned int dynamic_addr;
|
||||
size_t dynamic_size;
|
||||
char *program_interpreter;
|
||||
|
||||
ElfW(Ehdr) *elf_header;
|
||||
ElfW(Phdr) *elf_pheader, *segment;
|
||||
ElfW(Dyn) *dynamic_segment, *dyn_entry;
|
||||
char *dynamic_strings;
|
||||
|
||||
elf_header = (ElfW(Ehdr) *) file_contents;
|
||||
*osversion = 0;
|
||||
|
||||
if (elf_header->e_ident [EI_CLASS] != ElfW (CLASS))
|
||||
{
|
||||
if (opt_verbose)
|
||||
{
|
||||
if (elf_header->e_ident [EI_CLASS] == ELFCLASS32)
|
||||
error (0, 0, _("%s is a 32 bit ELF file.\n"), file_name);
|
||||
else if (elf_header->e_ident [EI_CLASS] == ELFCLASS64)
|
||||
error (0, 0, _("%s is a 64 bit ELF file.\n"), file_name);
|
||||
else
|
||||
error (0, 0, _("Unknown ELFCLASS in file %s.\n"), file_name);
|
||||
}
|
||||
return 1;
|
||||
}
|
||||
|
||||
if (elf_header->e_type != ET_DYN)
|
||||
{
|
||||
error (0, 0, _("%s is not a shared object file (Type: %d).\n"), file_name,
|
||||
elf_header->e_type);
|
||||
return 1;
|
||||
}
|
||||
|
||||
/* Get information from elf program header. */
|
||||
elf_pheader = (ElfW(Phdr) *) (elf_header->e_phoff + file_contents);
|
||||
check_ptr (elf_pheader);
|
||||
|
||||
/* The library is an elf library, now search for soname and
|
||||
libc5/libc6. */
|
||||
*flag = FLAG_ELF;
|
||||
|
||||
loadaddr = -1;
|
||||
dynamic_addr = 0;
|
||||
dynamic_size = 0;
|
||||
program_interpreter = NULL;
|
||||
for (i = 0, segment = elf_pheader;
|
||||
i < elf_header->e_phnum; i++, segment++)
|
||||
{
|
||||
check_ptr (segment);
|
||||
|
||||
switch (segment->p_type)
|
||||
{
|
||||
case PT_LOAD:
|
||||
if (loadaddr == (ElfW(Addr)) -1)
|
||||
loadaddr = segment->p_vaddr - segment->p_offset;
|
||||
break;
|
||||
|
||||
case PT_DYNAMIC:
|
||||
if (dynamic_addr)
|
||||
error (0, 0, _("more than one dynamic segment\n"));
|
||||
|
||||
dynamic_addr = segment->p_offset;
|
||||
dynamic_size = segment->p_filesz;
|
||||
break;
|
||||
|
||||
case PT_INTERP:
|
||||
program_interpreter = (char *) (file_contents + segment->p_offset);
|
||||
check_ptr (program_interpreter);
|
||||
|
||||
/* Check if this is enough to classify the binary. */
|
||||
for (j = 0; j < sizeof (interpreters) / sizeof (interpreters [0]);
|
||||
++j)
|
||||
if (strcmp (program_interpreter, interpreters[j].soname) == 0)
|
||||
{
|
||||
*flag = interpreters[j].flag;
|
||||
break;
|
||||
}
|
||||
break;
|
||||
|
||||
case PT_NOTE:
|
||||
if (!*osversion && segment->p_filesz == 32 && segment->p_align >= 4)
|
||||
{
|
||||
ElfW(Word) *abi_note = (ElfW(Word) *) (file_contents
|
||||
+ segment->p_offset);
|
||||
if (abi_note [0] == 4 && abi_note [1] == 16 && abi_note [2] == 1
|
||||
&& memcmp (abi_note + 3, "GNU", 4) == 0)
|
||||
*osversion = (abi_note [4] << 24) |
|
||||
((abi_note [5] & 0xff) << 16) |
|
||||
((abi_note [6] & 0xff) << 8) |
|
||||
(abi_note [7] & 0xff);
|
||||
}
|
||||
break;
|
||||
|
||||
default:
|
||||
break;
|
||||
}
|
||||
|
||||
}
|
||||
if (loadaddr == (ElfW(Addr)) -1)
|
||||
{
|
||||
/* Very strange. */
|
||||
loadaddr = 0;
|
||||
}
|
||||
|
||||
/* Now we can read the dynamic sections. */
|
||||
if (dynamic_size == 0)
|
||||
return 1;
|
||||
|
||||
dynamic_segment = (ElfW(Dyn) *) (file_contents + dynamic_addr);
|
||||
check_ptr (dynamic_segment);
|
||||
|
||||
/* Find the string table. */
|
||||
dynamic_strings = NULL;
|
||||
for (dyn_entry = dynamic_segment; dyn_entry->d_tag != DT_NULL;
|
||||
++dyn_entry)
|
||||
{
|
||||
check_ptr (dyn_entry);
|
||||
if (dyn_entry->d_tag == DT_STRTAB)
|
||||
{
|
||||
dynamic_strings = (char *) (file_contents + dyn_entry->d_un.d_val - loadaddr);
|
||||
check_ptr (dynamic_strings);
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
if (dynamic_strings == NULL)
|
||||
return 1;
|
||||
|
||||
/* Now read the DT_NEEDED and DT_SONAME entries. */
|
||||
for (dyn_entry = dynamic_segment; dyn_entry->d_tag != DT_NULL;
|
||||
++dyn_entry)
|
||||
{
|
||||
if (dyn_entry->d_tag == DT_NEEDED || dyn_entry->d_tag == DT_SONAME)
|
||||
{
|
||||
char *name = dynamic_strings + dyn_entry->d_un.d_val;
|
||||
check_ptr (name);
|
||||
|
||||
if (dyn_entry->d_tag == DT_NEEDED)
|
||||
{
|
||||
|
||||
if (*flag == FLAG_ELF)
|
||||
{
|
||||
/* Check if this is enough to classify the binary. */
|
||||
for (j = 0;
|
||||
j < sizeof (known_libs) / sizeof (known_libs [0]);
|
||||
++j)
|
||||
if (strcmp (name, known_libs [j].soname) == 0)
|
||||
{
|
||||
*flag = known_libs [j].flag;
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
else if (dyn_entry->d_tag == DT_SONAME)
|
||||
*soname = xstrdup (name);
|
||||
|
||||
/* Do we have everything we need? */
|
||||
if (*soname && *flag != FLAG_ELF)
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
/* We reach this point only if the file doesn't contain a DT_SONAME
|
||||
or if we can't classify the library. If it doesn't have a
|
||||
soname, return the name of the library. */
|
||||
if (*soname == NULL)
|
||||
*soname = xstrdup (lib);
|
||||
|
||||
return 0;
|
||||
}
|
||||
Reference in New Issue
Block a user