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/* Copyright (C) 1999-2018 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, see
<http://www.gnu.org/licenses/>. */
int process_elf32_file (const char *file_name, const char *lib, int *flag,
unsigned int *osversion, char **soname,
void *file_contents, size_t file_length);
int process_elf64_file (const char *file_name, const char *lib, int *flag,
unsigned int *osversion, char **soname,
void *file_contents, size_t file_length);
/* Read an unsigned leb128 value from P, store the value in VAL, return
P incremented past the value. We assume that a word is large enough to
hold any value so encoded; if it is smaller than a pointer on some target,
pointers should not be leb128 encoded on that target. */
static unsigned char *
read_uleb128 (unsigned char *p, unsigned long *val)
{
unsigned int shift = 0;
unsigned char byte;
unsigned long result;
result = 0;
do
{
byte = *p++;
result |= (byte & 0x7f) << shift;
shift += 7;
}
while (byte & 0x80);
*val = result;
return p;
}
#define ATTR_TAG_FILE 1
#define ABI_VFP_args 28
#define VFP_ARGS_IN_VFP_REGS 1
/* Check the ABI in the ARM attributes. Search through the section
headers looking for the ARM attributes section, then check the
VFP_ARGS attribute. */
static int is_library_hf(const char *file_name, void *file_contents, size_t file_length)
{
unsigned int i;
Elf32_Ehdr *ehdr = (Elf32_Ehdr *) file_contents;
Elf32_Shdr *shdrs;
shdrs = file_contents + ehdr->e_shoff;
for (i = 0; i < ehdr->e_shnum; i++)
{
if (SHT_ARM_ATTRIBUTES == shdrs[i].sh_type)
{
/* We've found a likely section. Load the contents and
* check the tags */
unsigned char *p = (unsigned char *)file_contents + shdrs[i].sh_offset;
unsigned char * end;
/* Sanity-check the attribute section details. Make sure
* that it's the "aeabi" section, that's all we care
* about. */
if (*p == 'A')
{
unsigned long len = shdrs[i].sh_size - 1;
unsigned long namelen;
p++;
while (len > 0)
{
unsigned long section_len = p[0] | p[1] << 8 | p[2] << 16 | p[3] << 24;
if (section_len > len)
section_len = len;
p += 4;
len -= section_len;
section_len -= 4;
if (0 != strcmp((char *)p, "aeabi"))
{
p += section_len;
continue;
}
namelen = strlen((char *)p) + 1;
p += namelen;
section_len -= namelen;
/* We're in a valid section. Walk through this
* section looking for the tag we care about
* (ABI_VFP_args) */
while (section_len > 0)
{
unsigned long val = 0;
unsigned long tag;
unsigned long size;
end = p;
tag = (*p++);
size = p[0] | p[1] << 8 | p[2] << 16 | p[3] << 24;
if (size > section_len)
size = section_len;
p += 4;
section_len -= size;
end += size;
if (ATTR_TAG_FILE != tag)
{
/* ignore, we don't care */
p = end;
continue;
}
while (p < end)
{
p = read_uleb128 (p, &tag);
/* Handle the different types of tag. */
if ( (tag == 4) || (tag == 5) || (tag == 67) )
{
/* Special cases for string values */
namelen = strlen((char *)p) + 1;
p += namelen;
}
else
{
p = read_uleb128 (p, &val);
}
if ( (tag == ABI_VFP_args) && (val == VFP_ARGS_IN_VFP_REGS) )
return 1;
}
}
}
}
}
}
return 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)
{
ElfW(Ehdr) *elf_header = (ElfW(Ehdr) *) file_contents;
int ret;
if (elf_header->e_ident [EI_CLASS] == ELFCLASS32)
{
Elf32_Ehdr *elf32_header = (Elf32_Ehdr *) elf_header;
ret = process_elf32_file (file_name, lib, flag, osversion, soname,
file_contents, file_length);
if (!ret && EF_ARM_EABI_VERSION (elf32_header->e_flags) == EF_ARM_EABI_VER5)
{
if (elf32_header->e_flags & EF_ARM_ABI_FLOAT_HARD)
*flag = FLAG_ARM_LIBHF|FLAG_ELF_LIBC6;
else if (elf32_header->e_flags & EF_ARM_ABI_FLOAT_SOFT)
*flag = FLAG_ARM_LIBSF|FLAG_ELF_LIBC6;
else if (is_library_hf(file_name, file_contents, file_length))
*flag = FLAG_ARM_LIBHF|FLAG_ELF_LIBC6;
else
/* We must assume the unmarked objects are compatible
with all ABI variants. Such objects may have been
generated in a transitional period when the ABI
tags were not added to all objects. */
*flag = FLAG_ELF_LIBC6;
}
}
else
{
ret = process_elf64_file (file_name, lib, flag, osversion, soname,
file_contents, file_length);
/* AArch64 libraries are always libc.so.6+. */
if (!ret)
*flag = FLAG_AARCH64_LIB64|FLAG_ELF_LIBC6;
}
return ret;
}
#undef __ELF_NATIVE_CLASS
#undef process_elf_file
#define process_elf_file process_elf32_file
#define __ELF_NATIVE_CLASS 32
#include "elf/readelflib.c"
#undef __ELF_NATIVE_CLASS
#undef process_elf_file
#define process_elf_file process_elf64_file
#define __ELF_NATIVE_CLASS 64
#include "elf/readelflib.c"
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