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fuchsia / third_party / binutils-gdb / refs/heads/upstream/master / . / bfd / compress.c
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/* Compressed section support (intended for debug sections).
Copyright (C) 2008-2024 Free Software Foundation, Inc.
This file is part of BFD, the Binary File Descriptor library.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
MA 02110-1301, USA. */
#include "sysdep.h"
#include <zlib.h>
#ifdef HAVE_ZSTD
#include <zstd.h>
#endif
#include "bfd.h"
#include "elf-bfd.h"
#include "libbfd.h"
#include "safe-ctype.h"
#include "libiberty.h"
#define MAX_COMPRESSION_HEADER_SIZE 24
/*
EXTERNAL
.{* Types of compressed DWARF debug sections. *}
.enum compressed_debug_section_type
.{
. COMPRESS_DEBUG_NONE = 0,
. COMPRESS_DEBUG_GNU_ZLIB = 1 << 1,
. COMPRESS_DEBUG_GABI_ZLIB = 1 << 2,
. COMPRESS_DEBUG_ZSTD = 1 << 3,
. COMPRESS_UNKNOWN = 1 << 4
.};
.
.{* Tuple for compressed_debug_section_type and their name. *}
.struct compressed_type_tuple
.{
. enum compressed_debug_section_type type;
. const char *name;
.};
.
.{* Compression header ch_type values. *}
.enum compression_type
.{
. ch_none = 0,
. ch_compress_zlib = 1 , {* Compressed with zlib. *}
. ch_compress_zstd = 2 {* Compressed with zstd (www.zstandard.org). *}
.};
.
.static inline char *
.bfd_debug_name_to_zdebug (bfd *abfd, const char *name)
.{
. size_t len = strlen (name);
. char *new_name = (char *) bfd_alloc (abfd, len + 2);
. if (new_name == NULL)
. return NULL;
. new_name[0] = '.';
. new_name[1] = 'z';
. memcpy (new_name + 2, name + 1, len);
. return new_name;
.}
.
.static inline char *
.bfd_zdebug_name_to_debug (bfd *abfd, const char *name)
.{
. size_t len = strlen (name);
. char *new_name = (char *) bfd_alloc (abfd, len);
. if (new_name == NULL)
. return NULL;
. new_name[0] = '.';
. memcpy (new_name + 1, name + 2, len - 1);
. return new_name;
.}
.
*/
/* Display texts for type of compressed DWARF debug sections. */
static const struct compressed_type_tuple compressed_debug_section_names[] =
{
{ COMPRESS_DEBUG_NONE, "none" },
{ COMPRESS_DEBUG_GABI_ZLIB, "zlib" },
{ COMPRESS_DEBUG_GNU_ZLIB, "zlib-gnu" },
{ COMPRESS_DEBUG_GABI_ZLIB, "zlib-gabi" },
{ COMPRESS_DEBUG_ZSTD, "zstd" },
};
/*
FUNCTION
bfd_get_compression_algorithm
SYNOPSIS
enum compressed_debug_section_type
bfd_get_compression_algorithm (const char *name);
DESCRIPTION
Return compressed_debug_section_type from a string representation.
*/
enum compressed_debug_section_type
bfd_get_compression_algorithm (const char *name)
{
for (unsigned i = 0; i < ARRAY_SIZE (compressed_debug_section_names); ++i)
if (strcasecmp (compressed_debug_section_names[i].name, name) == 0)
return compressed_debug_section_names[i].type;
return COMPRESS_UNKNOWN;
}
/*
FUNCTION
bfd_get_compression_algorithm_name
SYNOPSIS
const char *bfd_get_compression_algorithm_name
(enum compressed_debug_section_type type);
DESCRIPTION
Return compression algorithm name based on the type.
*/
const char *
bfd_get_compression_algorithm_name (enum compressed_debug_section_type type)
{
for (unsigned i = 0; i < ARRAY_SIZE (compressed_debug_section_names); ++i)
if (type == compressed_debug_section_names[i].type)
return compressed_debug_section_names[i].name;
return NULL;
}
/*
FUNCTION
bfd_update_compression_header
SYNOPSIS
void bfd_update_compression_header
(bfd *abfd, bfd_byte *contents, asection *sec);
DESCRIPTION
Set the compression header at CONTENTS of SEC in ABFD and update
elf_section_flags for compression.
*/
void
bfd_update_compression_header (bfd *abfd, bfd_byte *contents,
asection *sec)
{
if ((abfd->flags & BFD_COMPRESS) == 0)
abort ();
switch (bfd_get_flavour (abfd))
{
case bfd_target_elf_flavour:
if ((abfd->flags & BFD_COMPRESS_GABI) != 0)
{
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
struct bfd_elf_section_data * esd = elf_section_data (sec);
enum compression_type ch_type = (abfd->flags & BFD_COMPRESS_ZSTD
? ch_compress_zstd
: ch_compress_zlib);
/* Set the SHF_COMPRESSED bit. */
elf_section_flags (sec) |= SHF_COMPRESSED;
if (bed->s->elfclass == ELFCLASS32)
{
Elf32_External_Chdr *echdr = (Elf32_External_Chdr *) contents;
bfd_put_32 (abfd, ch_type, &echdr->ch_type);
bfd_put_32 (abfd, sec->size, &echdr->ch_size);
bfd_put_32 (abfd, 1u << sec->alignment_power,
&echdr->ch_addralign);
/* bfd_log2 (alignof (Elf32_Chdr)) */
bfd_set_section_alignment (sec, 2);
esd->this_hdr.sh_addralign = 4;
}
else
{
Elf64_External_Chdr *echdr = (Elf64_External_Chdr *) contents;
bfd_put_32 (abfd, ch_type, &echdr->ch_type);
bfd_put_32 (abfd, 0, &echdr->ch_reserved);
bfd_put_64 (abfd, sec->size, &echdr->ch_size);
bfd_put_64 (abfd, UINT64_C (1) << sec->alignment_power,
&echdr->ch_addralign);
/* bfd_log2 (alignof (Elf64_Chdr)) */
bfd_set_section_alignment (sec, 3);
esd->this_hdr.sh_addralign = 8;
}
break;
}
/* Clear the SHF_COMPRESSED bit. */
elf_section_flags (sec) &= ~SHF_COMPRESSED;
/* Fall through. */
default:
/* Write the zlib header. It should be "ZLIB" followed by
the uncompressed section size, 8 bytes in big-endian
order. */
memcpy (contents, "ZLIB", 4);
bfd_putb64 (sec->size, contents + 4);
/* No way to keep the original alignment, just use 1 always. */
bfd_set_section_alignment (sec, 0);
break;
}
}
/* Check the compression header at CONTENTS of SEC in ABFD and store the
ch_type in CH_TYPE, uncompressed size in UNCOMPRESSED_SIZE, and the
uncompressed data alignment in UNCOMPRESSED_ALIGNMENT_POWER if the
compression header is valid. */
static bool
bfd_check_compression_header (bfd *abfd, bfd_byte *contents,
asection *sec,
enum compression_type *ch_type,
bfd_size_type *uncompressed_size,
unsigned int *uncompressed_alignment_power)
{
if (bfd_get_flavour (abfd) == bfd_target_elf_flavour
&& (elf_section_flags (sec) & SHF_COMPRESSED) != 0)
{
Elf_Internal_Chdr chdr;
const struct elf_backend_data *bed = get_elf_backend_data (abfd);
if (bed->s->elfclass == ELFCLASS32)
{
Elf32_External_Chdr *echdr = (Elf32_External_Chdr *) contents;
chdr.ch_type = bfd_get_32 (abfd, &echdr->ch_type);
chdr.ch_size = bfd_get_32 (abfd, &echdr->ch_size);
chdr.ch_addralign = bfd_get_32 (abfd, &echdr->ch_addralign);
}
else
{
Elf64_External_Chdr *echdr = (Elf64_External_Chdr *) contents;
chdr.ch_type = bfd_get_32 (abfd, &echdr->ch_type);
chdr.ch_size = bfd_get_64 (abfd, &echdr->ch_size);
chdr.ch_addralign = bfd_get_64 (abfd, &echdr->ch_addralign);
}
*ch_type = chdr.ch_type;
if ((chdr.ch_type == ch_compress_zlib
|| chdr.ch_type == ch_compress_zstd)
&& chdr.ch_addralign == (chdr.ch_addralign & -chdr.ch_addralign))
{
*uncompressed_size = chdr.ch_size;
*uncompressed_alignment_power = bfd_log2 (chdr.ch_addralign);
return true;
}
}
return false;
}
/*
FUNCTION
bfd_get_compression_header_size
SYNOPSIS
int bfd_get_compression_header_size (bfd *abfd, asection *sec);
DESCRIPTION
Return the size of the compression header of SEC in ABFD.
*/
int
bfd_get_compression_header_size (bfd *abfd, asection *sec)
{
if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
{
if (sec == NULL)
{
if (!(abfd->flags & BFD_COMPRESS_GABI))
return 0;
}
else if (!(elf_section_flags (sec) & SHF_COMPRESSED))
return 0;
if (get_elf_backend_data (abfd)->s->elfclass == ELFCLASS32)
return sizeof (Elf32_External_Chdr);
else
return sizeof (Elf64_External_Chdr);
}
return 0;
}
/*
FUNCTION
bfd_convert_section_setup
SYNOPSIS
bool bfd_convert_section_setup
(bfd *ibfd, asection *isec, bfd *obfd,
const char **new_name, bfd_size_type *new_size);
DESCRIPTION
Do early setup for objcopy, when copying @var{isec} in input
BFD @var{ibfd} to output BFD @var{obfd}. Returns the name and
size of the output section.
*/
bool
bfd_convert_section_setup (bfd *ibfd, asection *isec, bfd *obfd,
const char **new_name, bfd_size_type *new_size)
{
bfd_size_type hdr_size;
if ((isec->flags & SEC_DEBUGGING) != 0
&& (isec->flags & SEC_HAS_CONTENTS) != 0)
{
const char *name = *new_name;
if ((obfd->flags & (BFD_DECOMPRESS | BFD_COMPRESS_GABI)) != 0)
{
/* When we decompress or compress with SHF_COMPRESSED,
convert section name from .zdebug_* to .debug_*. */
if (startswith (name, ".zdebug_"))
{
name = bfd_zdebug_name_to_debug (obfd, name);
if (name == NULL)
return false;
}
}
/* PR binutils/18087: Compression does not always make a
section smaller. So only rename the section when
compression has actually taken place. If input section
name is .zdebug_*, we should never compress it again. */
else if (isec->compress_status == COMPRESS_SECTION_DONE
&& startswith (name, ".debug_"))
{
name = bfd_debug_name_to_zdebug (obfd, name);
if (name == NULL)
return false;
}
*new_name = name;
}
*new_size = bfd_section_size (isec);
/* Do nothing if either input or output aren't ELF. */
if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour
|| bfd_get_flavour (obfd) != bfd_target_elf_flavour)
return true;
/* Do nothing if ELF classes of input and output are the same. */
if (get_elf_backend_data (ibfd)->s->elfclass
== get_elf_backend_data (obfd)->s->elfclass)
return true;
/* Convert GNU property size. */
if (startswith (isec->name, NOTE_GNU_PROPERTY_SECTION_NAME))
{
*new_size = _bfd_elf_convert_gnu_property_size (ibfd, obfd);
return true;
}
/* Do nothing if input file will be decompressed. */
if ((ibfd->flags & BFD_DECOMPRESS))
return true;
/* Do nothing if the input section isn't a SHF_COMPRESSED section. */
hdr_size = bfd_get_compression_header_size (ibfd, isec);
if (hdr_size == 0)
return true;
/* Adjust the size of the output SHF_COMPRESSED section. */
if (hdr_size == sizeof (Elf32_External_Chdr))
*new_size += sizeof (Elf64_External_Chdr) - sizeof (Elf32_External_Chdr);
else
*new_size -= sizeof (Elf64_External_Chdr) - sizeof (Elf32_External_Chdr);
return true;
}
/*
FUNCTION
bfd_convert_section_contents
SYNOPSIS
bool bfd_convert_section_contents
(bfd *ibfd, asection *isec, bfd *obfd,
bfd_byte **ptr, bfd_size_type *ptr_size);
DESCRIPTION
Convert the contents, stored in @var{*ptr}, of the section
@var{isec} in input BFD @var{ibfd} to output BFD @var{obfd}
if needed. The original buffer pointed to by @var{*ptr} may
be freed and @var{*ptr} is returned with memory malloc'd by this
function, and the new size written to @var{ptr_size}.
*/
bool
bfd_convert_section_contents (bfd *ibfd, sec_ptr isec, bfd *obfd,
bfd_byte **ptr, bfd_size_type *ptr_size)
{
bfd_byte *contents;
bfd_size_type ihdr_size, ohdr_size, size;
Elf_Internal_Chdr chdr;
bool use_memmove;
/* Do nothing if either input or output aren't ELF. */
if (bfd_get_flavour (ibfd) != bfd_target_elf_flavour
|| bfd_get_flavour (obfd) != bfd_target_elf_flavour)
return true;
/* Do nothing if ELF classes of input and output are the same. */
if (get_elf_backend_data (ibfd)->s->elfclass
== get_elf_backend_data (obfd)->s->elfclass)
return true;
/* Convert GNU properties. */
if (startswith (isec->name, NOTE_GNU_PROPERTY_SECTION_NAME))
return _bfd_elf_convert_gnu_properties (ibfd, isec, obfd, ptr,
ptr_size);
/* Do nothing if input file will be decompressed. */
if ((ibfd->flags & BFD_DECOMPRESS))
return true;
/* Do nothing if the input section isn't a SHF_COMPRESSED section. */
ihdr_size = bfd_get_compression_header_size (ibfd, isec);
if (ihdr_size == 0)
return true;
/* PR 25221. Check for corrupt input sections. */
if (ihdr_size > bfd_get_section_limit (ibfd, isec))
/* FIXME: Issue a warning about a corrupt
compression header size field ? */
return false;
contents = *ptr;
/* Convert the contents of the input SHF_COMPRESSED section to
output. Get the input compression header and the size of the
output compression header. */
if (ihdr_size == sizeof (Elf32_External_Chdr))
{
Elf32_External_Chdr *echdr = (Elf32_External_Chdr *) contents;
chdr.ch_type = bfd_get_32 (ibfd, &echdr->ch_type);
chdr.ch_size = bfd_get_32 (ibfd, &echdr->ch_size);
chdr.ch_addralign = bfd_get_32 (ibfd, &echdr->ch_addralign);
ohdr_size = sizeof (Elf64_External_Chdr);
use_memmove = false;
}
else if (ihdr_size != sizeof (Elf64_External_Chdr))
{
/* FIXME: Issue a warning about a corrupt
compression header size field ? */
return false;
}
else
{
Elf64_External_Chdr *echdr = (Elf64_External_Chdr *) contents;
chdr.ch_type = bfd_get_32 (ibfd, &echdr->ch_type);
chdr.ch_size = bfd_get_64 (ibfd, &echdr->ch_size);
chdr.ch_addralign = bfd_get_64 (ibfd, &echdr->ch_addralign);
ohdr_size = sizeof (Elf32_External_Chdr);
use_memmove = true;
}
size = bfd_section_size (isec) - ihdr_size + ohdr_size;
if (!use_memmove)
{
contents = (bfd_byte *) bfd_malloc (size);
if (contents == NULL)
return false;
}
/* Write out the output compression header. */
if (ohdr_size == sizeof (Elf32_External_Chdr))
{
Elf32_External_Chdr *echdr = (Elf32_External_Chdr *) contents;
bfd_put_32 (obfd, chdr.ch_type, &echdr->ch_type);
bfd_put_32 (obfd, chdr.ch_size, &echdr->ch_size);
bfd_put_32 (obfd, chdr.ch_addralign, &echdr->ch_addralign);
}
else
{
Elf64_External_Chdr *echdr = (Elf64_External_Chdr *) contents;
bfd_put_32 (obfd, chdr.ch_type, &echdr->ch_type);
bfd_put_32 (obfd, 0, &echdr->ch_reserved);
bfd_put_64 (obfd, chdr.ch_size, &echdr->ch_size);
bfd_put_64 (obfd, chdr.ch_addralign, &echdr->ch_addralign);
}
/* Copy the compressed contents. */
if (use_memmove)
memmove (contents + ohdr_size, *ptr + ihdr_size, size - ohdr_size);
else
{
memcpy (contents + ohdr_size, *ptr + ihdr_size, size - ohdr_size);
free (*ptr);
*ptr = contents;
}
*ptr_size = size;
return true;
}
static bool
decompress_contents (bool is_zstd, bfd_byte *compressed_buffer,
bfd_size_type compressed_size,
bfd_byte *uncompressed_buffer,
bfd_size_type uncompressed_size)
{
if (is_zstd)
{
#ifdef HAVE_ZSTD
size_t ret = ZSTD_decompress (uncompressed_buffer, uncompressed_size,
compressed_buffer, compressed_size);
return !ZSTD_isError (ret);
#endif
}
z_stream strm;
int rc;
/* It is possible the section consists of several compressed
buffers concatenated together, so we uncompress in a loop. */
/* PR 18313: The state field in the z_stream structure is supposed
to be invisible to the user (ie us), but some compilers will
still complain about it being used without initialisation. So
we first zero the entire z_stream structure and then set the fields
that we need. */
memset (& strm, 0, sizeof strm);
strm.avail_in = compressed_size;
strm.next_in = (Bytef*) compressed_buffer;
strm.avail_out = uncompressed_size;
/* FIXME: strm.avail_in and strm.avail_out are typically unsigned
int. Supporting sizes that don't fit in an unsigned int is
possible but will require some rewriting of this function. */
if (strm.avail_in != compressed_size || strm.avail_out != uncompressed_size)
return false;
BFD_ASSERT (Z_OK == 0);
rc = inflateInit (&strm);
while (strm.avail_in > 0 && strm.avail_out > 0)
{
if (rc != Z_OK)
break;
strm.next_out = ((Bytef*) uncompressed_buffer
+ (uncompressed_size - strm.avail_out));
rc = inflate (&strm, Z_FINISH);
if (rc != Z_STREAM_END)
break;
rc = inflateReset (&strm);
}
return inflateEnd (&strm) == Z_OK && rc == Z_OK && strm.avail_out == 0;
}
/* Compress section contents using zlib/zstd and store
as the contents field. This function assumes the contents
field was allocated using bfd_malloc() or equivalent.
Return the uncompressed size if the full section contents is
compressed successfully. Otherwise return (bfd_size_type) -1. */
static bfd_size_type
bfd_compress_section_contents (bfd *abfd, sec_ptr sec)
{
bfd_byte *input_buffer;
uLong compressed_size;
bfd_byte *buffer;
bfd_size_type buffer_size;
int zlib_size = 0;
int orig_header_size;
bfd_size_type uncompressed_size;
unsigned int uncompressed_alignment_pow;
enum compression_type ch_type = ch_none;
int new_header_size = bfd_get_compression_header_size (abfd, NULL);
bool compressed
= bfd_is_section_compressed_info (abfd, sec,
&orig_header_size,
&uncompressed_size,
&uncompressed_alignment_pow,
&ch_type);
bool update = false;
/* We shouldn't be trying to decompress unsupported compressed sections. */
if (compressed && orig_header_size < 0)
abort ();
/* PR 31455: Check for a corrupt uncompressed size. */
if (uncompressed_size == (bfd_size_type) -1)
return uncompressed_size;
/* Either ELF compression header or the 12-byte, "ZLIB" + 8-byte size,
overhead in .zdebug* section. */
if (!new_header_size)
new_header_size = 12;
if (ch_type == ch_none)
orig_header_size = 12;
input_buffer = sec->contents;
if (compressed)
{
zlib_size = sec->size - orig_header_size;
compressed_size = zlib_size + new_header_size;
/* If we are converting between zlib-gnu and zlib-gabi then the
compressed contents just need to be moved. */
update = (ch_type < ch_compress_zstd
&& (abfd->flags & BFD_COMPRESS_ZSTD) == 0);
/* Uncompress when not just moving contents or when compressed
is not smaller than uncompressed. */
if (!update || compressed_size >= uncompressed_size)
{
buffer_size = uncompressed_size;
buffer = bfd_malloc (buffer_size);
if (buffer == NULL)
return (bfd_size_type) -1;
if (!decompress_contents (ch_type == ch_compress_zstd,
input_buffer + orig_header_size,
zlib_size, buffer, buffer_size))
{
bfd_set_error (bfd_error_bad_value);
free (buffer);
return (bfd_size_type) -1;
}
free (input_buffer);
bfd_set_section_alignment (sec, uncompressed_alignment_pow);
sec->contents = buffer;
sec->flags |= SEC_IN_MEMORY;
sec->compress_status = COMPRESS_SECTION_NONE;
sec->size = uncompressed_size;
input_buffer = buffer;
}
}
if (!update)
compressed_size = compressBound (uncompressed_size) + new_header_size;
buffer_size = compressed_size;
buffer = bfd_alloc (abfd, buffer_size);
if (buffer == NULL)
return (bfd_size_type) -1;
if (update)
{
if (compressed_size < uncompressed_size)
memcpy (buffer + new_header_size,
input_buffer + orig_header_size,
zlib_size);
}
else
{
if (abfd->flags & BFD_COMPRESS_ZSTD)
{
#if HAVE_ZSTD
compressed_size = ZSTD_compress (buffer + new_header_size,
compressed_size,
input_buffer,
uncompressed_size,
ZSTD_CLEVEL_DEFAULT);
if (ZSTD_isError (compressed_size))
{
bfd_release (abfd, buffer);
bfd_set_error (bfd_error_bad_value);
return (bfd_size_type) -1;
}
#endif
}
else if (compress ((Bytef *) buffer + new_header_size, &compressed_size,
(const Bytef *) input_buffer, uncompressed_size)
!= Z_OK)
{
bfd_release (abfd, buffer);
bfd_set_error (bfd_error_bad_value);
return (bfd_size_type) -1;
}
compressed_size += new_header_size;
}
/* If compression didn't make the section smaller, keep it uncompressed. */
if (compressed_size >= uncompressed_size)
{
memcpy (buffer, input_buffer, uncompressed_size);
if (bfd_get_flavour (abfd) == bfd_target_elf_flavour)
elf_section_flags (sec) &= ~SHF_COMPRESSED;
sec->compress_status = COMPRESS_SECTION_NONE;
}
else
{
sec->size = uncompressed_size;
bfd_update_compression_header (abfd, buffer, sec);
sec->size = compressed_size;
sec->compress_status = COMPRESS_SECTION_DONE;
}
sec->contents = buffer;
sec->flags |= SEC_IN_MEMORY;
free (input_buffer);
return uncompressed_size;
}
/*
FUNCTION
bfd_get_full_section_contents
SYNOPSIS
bool bfd_get_full_section_contents
(bfd *abfd, asection *section, bfd_byte **ptr);
DESCRIPTION
Read all data from @var{section} in BFD @var{abfd}, decompress
if needed, and store in @var{*ptr}. If @var{*ptr} is NULL,
return @var{*ptr} with memory malloc'd by this function.
Return @code{TRUE} if the full section contents is retrieved
successfully. If the section has no contents then this function
returns @code{TRUE} but @var{*ptr} is set to NULL.
*/
bool
bfd_get_full_section_contents (bfd *abfd, sec_ptr sec, bfd_byte **ptr)
{
bfd_size_type readsz = bfd_get_section_limit_octets (abfd, sec);
bfd_size_type allocsz = bfd_get_section_alloc_size (abfd, sec);
bfd_byte *p = *ptr;
bool ret;
bfd_size_type save_size;
bfd_size_type save_rawsize;
bfd_byte *compressed_buffer;
unsigned int compression_header_size;
const unsigned int compress_status = sec->compress_status;
if (allocsz == 0)
{
*ptr = NULL;
return true;
}
if (p == NULL
&& compress_status != COMPRESS_SECTION_DONE
&& bfd_section_size_insane (abfd, sec))
{
/* PR 24708: Avoid attempts to allocate a ridiculous amount
of memory. */
_bfd_error_handler
/* xgettext:c-format */
(_("error: %pB(%pA) is too large (%#" PRIx64 " bytes)"),
abfd, sec, (uint64_t) readsz);
return false;
}
switch (compress_status)
{
case COMPRESS_SECTION_NONE:
if (p == NULL && !sec->mmapped_p)
{
p = (bfd_byte *) bfd_malloc (allocsz);
if (p == NULL)
{
/* PR 20801: Provide a more helpful error message. */
if (bfd_get_error () == bfd_error_no_memory)
_bfd_error_handler
/* xgettext:c-format */
(_("error: %pB(%pA) is too large (%#" PRIx64 " bytes)"),
abfd, sec, (uint64_t) allocsz);
return false;
}
}
if (!bfd_get_section_contents (abfd, sec, p, 0, readsz))
{
if (*ptr != p)
free (p);
return false;
}
*ptr = p;
return true;
case DECOMPRESS_SECTION_ZLIB:
case DECOMPRESS_SECTION_ZSTD:
/* Read in the full compressed section contents. */
compressed_buffer = (bfd_byte *) bfd_malloc (sec->compressed_size);
if (compressed_buffer == NULL)
return false;
save_rawsize = sec->rawsize;
save_size = sec->size;
/* Clear rawsize, set size to compressed size and set compress_status
to COMPRESS_SECTION_NONE. If the compressed size is bigger than
the uncompressed size, bfd_get_section_contents will fail. */
sec->rawsize = 0;
sec->size = sec->compressed_size;
sec->compress_status = COMPRESS_SECTION_NONE;
ret = bfd_get_section_contents (abfd, sec, compressed_buffer,
0, sec->compressed_size);
/* Restore rawsize and size. */
sec->rawsize = save_rawsize;
sec->size = save_size;
sec->compress_status = compress_status;
if (!ret)
goto fail_compressed;
if (p == NULL)
p = (bfd_byte *) bfd_malloc (allocsz);
if (p == NULL)
goto fail_compressed;
compression_header_size = bfd_get_compression_header_size (abfd, sec);
if (compression_header_size == 0)
/* Set header size to the zlib header size if it is a
SHF_COMPRESSED section. */
compression_header_size = 12;
bool is_zstd = compress_status == DECOMPRESS_SECTION_ZSTD;
if (!decompress_contents (
is_zstd, compressed_buffer + compression_header_size,
sec->compressed_size - compression_header_size, p, readsz))
{
bfd_set_error (bfd_error_bad_value);
if (p != *ptr)
free (p);
fail_compressed:
free (compressed_buffer);
return false;
}
free (compressed_buffer);
*ptr = p;
return true;
case COMPRESS_SECTION_DONE:
if (sec->contents == NULL)
return false;
if (p == NULL)
{
p = (bfd_byte *) bfd_malloc (allocsz);
if (p == NULL)
return false;
*ptr = p;
}
/* PR 17512; file: 5bc29788. */
if (p != sec->contents)
memcpy (p, sec->contents, readsz);
return true;
default:
abort ();
}
}
/*
FUNCTION
bfd_is_section_compressed_info
SYNOPSIS
bool bfd_is_section_compressed_info
(bfd *abfd, asection *section,
int *compression_header_size_p,
bfd_size_type *uncompressed_size_p,
unsigned int *uncompressed_alignment_power_p,
enum compression_type *ch_type);
DESCRIPTION
Return @code{TRUE} if @var{section} is compressed. Compression
header size is returned in @var{compression_header_size_p},
uncompressed size is returned in @var{uncompressed_size_p}
and the uncompressed data alignement power is returned in
@var{uncompressed_align_pow_p}. If compression is
unsupported, compression header size is returned with -1
and uncompressed size is returned with 0.
*/
bool
bfd_is_section_compressed_info (bfd *abfd, sec_ptr sec,
int *compression_header_size_p,
bfd_size_type *uncompressed_size_p,
unsigned int *uncompressed_align_pow_p,
enum compression_type *ch_type)
{
bfd_byte header[MAX_COMPRESSION_HEADER_SIZE];
int compression_header_size;
int header_size;
unsigned int saved = sec->compress_status;
bool compressed;
*uncompressed_align_pow_p = 0;
compression_header_size = bfd_get_compression_header_size (abfd, sec);
if (compression_header_size > MAX_COMPRESSION_HEADER_SIZE)
abort ();
header_size = compression_header_size ? compression_header_size : 12;
/* Don't decompress the section. */
sec->compress_status = COMPRESS_SECTION_NONE;
/* Read the header. */
if (bfd_get_section_contents (abfd, sec, header, 0, header_size))
{
if (compression_header_size == 0)
/* In this case, it should be "ZLIB" followed by the uncompressed
section size, 8 bytes in big-endian order. */
compressed = startswith ((char*) header , "ZLIB");
else
compressed = true;
}
else
compressed = false;
*uncompressed_size_p = sec->size;
if (compressed)
{
if (compression_header_size != 0)
{
if (!bfd_check_compression_header (abfd, header, sec, ch_type,
uncompressed_size_p,
uncompressed_align_pow_p))
compression_header_size = -1;
}
/* Check for the pathalogical case of a debug string section that
contains the string ZLIB.... as the first entry. We assume that
no uncompressed .debug_str section would ever be big enough to
have the first byte of its (big-endian) size be non-zero. */
else if (strcmp (sec->name, ".debug_str") == 0
&& ISPRINT (header[4]))
compressed = false;
else
*uncompressed_size_p = bfd_getb64 (header + 4);
}
/* Restore compress_status. */
sec->compress_status = saved;
*compression_header_size_p = compression_header_size;
return compressed;
}
/*
FUNCTION
bfd_is_section_compressed
SYNOPSIS
bool bfd_is_section_compressed
(bfd *abfd, asection *section);
DESCRIPTION
Return @code{TRUE} if @var{section} is compressed.
*/
bool
bfd_is_section_compressed (bfd *abfd, sec_ptr sec)
{
int compression_header_size;
bfd_size_type uncompressed_size;
unsigned int uncompressed_align_power;
enum compression_type ch_type;
return (bfd_is_section_compressed_info (abfd, sec,
&compression_header_size,
&uncompressed_size,
&uncompressed_align_power,
&ch_type)
&& compression_header_size >= 0
&& uncompressed_size > 0);
}
/*
FUNCTION
bfd_init_section_decompress_status
SYNOPSIS
bool bfd_init_section_decompress_status
(bfd *abfd, asection *section);
DESCRIPTION
Record compressed section size, update section size with
decompressed size and set compress_status to
DECOMPRESS_SECTION_{ZLIB,ZSTD}.
Return @code{FALSE} if the section is not a valid compressed
section. Otherwise, return @code{TRUE}.
*/
bool
bfd_init_section_decompress_status (bfd *abfd, sec_ptr sec)
{
bfd_byte header[MAX_COMPRESSION_HEADER_SIZE];
int compression_header_size;
int header_size;
bfd_size_type uncompressed_size;
unsigned int uncompressed_alignment_power = 0;
enum compression_type ch_type;
z_stream strm;
compression_header_size = bfd_get_compression_header_size (abfd, sec);
if (compression_header_size > MAX_COMPRESSION_HEADER_SIZE)
abort ();
header_size = compression_header_size ? compression_header_size : 12;
/* Read the header. */
if (sec->rawsize != 0
|| sec->contents != NULL
|| sec->compress_status != COMPRESS_SECTION_NONE
|| !bfd_get_section_contents (abfd, sec, header, 0, header_size))
{
bfd_set_error (bfd_error_invalid_operation);
return false;
}
if (compression_header_size == 0)
{
/* In this case, it should be "ZLIB" followed by the uncompressed
section size, 8 bytes in big-endian order. */
if (! startswith ((char*) header, "ZLIB"))
{
bfd_set_error (bfd_error_wrong_format);
return false;
}
uncompressed_size = bfd_getb64 (header + 4);
ch_type = ch_none;
}
else if (!bfd_check_compression_header (abfd, header, sec,
&ch_type,
&uncompressed_size,
&uncompressed_alignment_power))
{
bfd_set_error (bfd_error_wrong_format);
return false;
}
/* PR28530, reject sizes unsupported by decompress_contents. */
strm.avail_in = sec->size;
strm.avail_out = uncompressed_size;
if (strm.avail_in != sec->size || strm.avail_out != uncompressed_size)
{
bfd_set_error (bfd_error_nonrepresentable_section);
return false;
}
sec->compressed_size = sec->size;
sec->size = uncompressed_size;
bfd_set_section_alignment (sec, uncompressed_alignment_power);
sec->compress_status = (ch_type == ch_compress_zstd
? DECOMPRESS_SECTION_ZSTD : DECOMPRESS_SECTION_ZLIB);
return true;
}
/*
FUNCTION
bfd_init_section_compress_status
SYNOPSIS
bool bfd_init_section_compress_status
(bfd *abfd, asection *section);
DESCRIPTION
If open for read, compress section, update section size with
compressed size and set compress_status to COMPRESS_SECTION_DONE.
Return @code{FALSE} if the section is not a valid compressed
section. Otherwise, return @code{TRUE}.
*/
bool
bfd_init_section_compress_status (bfd *abfd, sec_ptr sec)
{
bfd_size_type uncompressed_size;
bfd_byte *uncompressed_buffer;
/* Error if not opened for read. */
if (abfd->direction != read_direction
|| sec->size == 0
|| sec->rawsize != 0
|| sec->contents != NULL
|| sec->compress_status != COMPRESS_SECTION_NONE
|| bfd_section_size_insane (abfd, sec))
{
bfd_set_error (bfd_error_invalid_operation);
return false;
}
/* Read in the full section contents and compress it. */
uncompressed_size = sec->size;
uncompressed_buffer = (bfd_byte *) bfd_malloc (uncompressed_size);
/* PR 21431 */
if (uncompressed_buffer == NULL)
return false;
if (!bfd_get_section_contents (abfd, sec, uncompressed_buffer,
0, uncompressed_size))
{
free (uncompressed_buffer);
return false;
}
sec->contents = uncompressed_buffer;
if (bfd_compress_section_contents (abfd, sec) == (bfd_size_type) -1)
{
free (sec->contents);
sec->contents = NULL;
return false;
}
return true;
}
/*
FUNCTION
bfd_compress_section
SYNOPSIS
bool bfd_compress_section
(bfd *abfd, asection *section, bfd_byte *uncompressed_buffer);
DESCRIPTION
If open for write, compress section, update section size with
compressed size and set compress_status to COMPRESS_SECTION_DONE.
Return @code{FALSE} if compression fail. Otherwise, return
@code{TRUE}. UNCOMPRESSED_BUFFER is freed in both cases.
*/
bool
bfd_compress_section (bfd *abfd, sec_ptr sec, bfd_byte *uncompressed_buffer)
{
bfd_size_type uncompressed_size = sec->size;
/* Error if not opened for write. */
if (abfd->direction != write_direction
|| uncompressed_size == 0
|| uncompressed_buffer == NULL
|| sec->contents != NULL
|| sec->compressed_size != 0
|| sec->compress_status != COMPRESS_SECTION_NONE)
{
bfd_set_error (bfd_error_invalid_operation);
return false;
}
sec->contents = uncompressed_buffer;
if (bfd_compress_section_contents (abfd, sec) == (bfd_size_type) -1)
{
free (sec->contents);
sec->contents = NULL;
return false;
}
return true;
}