/* Compressed section support (intended for debug sections).
- Copyright 2008, 2010, 2011, 2012
- Free Software Foundation, Inc.
+ Copyright (C) 2008-2017 Free Software Foundation, Inc.
This file is part of BFD, the Binary File Descriptor library.
MA 02110-1301, USA. */
#include "sysdep.h"
+#include <zlib.h>
#include "bfd.h"
#include "libbfd.h"
-#ifdef HAVE_ZLIB_H
-#include <zlib.h>
-#endif
+#include "safe-ctype.h"
+
+#define MAX_COMPRESSION_HEADER_SIZE 24
-#ifdef HAVE_ZLIB_H
static bfd_boolean
decompress_contents (bfd_byte *compressed_buffer,
bfd_size_type compressed_size,
/* It is possible the section consists of several compressed
buffers concatenated together, so we uncompress in a loop. */
- strm.zalloc = NULL;
- strm.zfree = NULL;
- strm.opaque = NULL;
- strm.avail_in = compressed_size - 12;
- strm.next_in = (Bytef*) compressed_buffer + 12;
+ /* 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;
BFD_ASSERT (Z_OK == 0);
rc |= inflateEnd (&strm);
return rc == Z_OK && strm.avail_out == 0;
}
-#endif
-
-/*
-FUNCTION
- bfd_compress_section_contents
-SYNOPSIS
- bfd_boolean bfd_compress_section_contents
- (bfd *abfd, asection *section, bfd_byte *uncompressed_buffer,
- bfd_size_type uncompressed_size);
+/* Compress data of the size specified in @var{uncompressed_size}
+ and pointed to by @var{uncompressed_buffer} using zlib and store
+ as the contents field. This function assumes the contents
+ field was allocated using bfd_malloc() or equivalent.
-DESCRIPTION
+ Return the uncompressed size if the full section contents is
+ compressed successfully. Otherwise return 0. */
- Compress data of the size specified in @var{uncompressed_size}
- and pointed to by @var{uncompressed_buffer} using zlib and store
- as the contents field. This function assumes the contents
- field was allocated using bfd_malloc() or equivalent. If zlib
- is not installed on this machine, the input is unmodified.
-
- Return @code{TRUE} if the full section contents is compressed
- successfully.
-*/
-
-bfd_boolean
-bfd_compress_section_contents (bfd *abfd ATTRIBUTE_UNUSED,
- sec_ptr sec ATTRIBUTE_UNUSED,
- bfd_byte *uncompressed_buffer ATTRIBUTE_UNUSED,
- bfd_size_type uncompressed_size ATTRIBUTE_UNUSED)
+static bfd_size_type
+bfd_compress_section_contents (bfd *abfd, sec_ptr sec,
+ bfd_byte *uncompressed_buffer,
+ bfd_size_type uncompressed_size)
{
-#ifndef HAVE_ZLIB_H
- bfd_set_error (bfd_error_invalid_operation);
- return FALSE;
-#else
uLong compressed_size;
- bfd_byte *compressed_buffer;
+ bfd_byte *buffer;
+ bfd_size_type buffer_size;
+ bfd_boolean decompress;
+ int zlib_size = 0;
+ int orig_compression_header_size;
+ bfd_size_type orig_uncompressed_size;
+ int header_size = bfd_get_compression_header_size (abfd, NULL);
+ bfd_boolean compressed
+ = bfd_is_section_compressed_with_header (abfd, sec,
+ &orig_compression_header_size,
+ &orig_uncompressed_size);
+
+ /* Either ELF compression header or the 12-byte, "ZLIB" + 8-byte size,
+ overhead in .zdebug* section. */
+ if (!header_size)
+ header_size = 12;
+
+ if (compressed)
+ {
+ /* We shouldn't decompress unsupported compressed section. */
+ if (orig_compression_header_size < 0)
+ abort ();
- compressed_size = compressBound (uncompressed_size) + 12;
- compressed_buffer = (bfd_byte *) bfd_malloc (compressed_size);
+ /* Different compression schemes. Just move the compressed section
+ contents to the right position. */
+ if (orig_compression_header_size == 0)
+ {
+ /* Convert it from .zdebug* section. Get the uncompressed
+ size first. We need to substract the 12-byte overhead in
+ .zdebug* section. Set orig_compression_header_size to
+ the 12-bye overhead. */
+ orig_compression_header_size = 12;
+ zlib_size = uncompressed_size - 12;
+ }
+ else
+ {
+ /* Convert it to .zdebug* section. */
+ zlib_size = uncompressed_size - orig_compression_header_size;
+ }
- if (compressed_buffer == NULL)
- return FALSE;
+ /* Add the header size. */
+ compressed_size = zlib_size + header_size;
+ }
+ else
+ compressed_size = compressBound (uncompressed_size) + header_size;
- if (compress ((Bytef*) compressed_buffer + 12,
- &compressed_size,
- (const Bytef*) uncompressed_buffer,
- uncompressed_size) != Z_OK)
+ /* Uncompress if it leads to smaller size. */
+ if (compressed && compressed_size > orig_uncompressed_size)
{
- free (compressed_buffer);
- bfd_set_error (bfd_error_bad_value);
- return FALSE;
+ decompress = TRUE;
+ buffer_size = orig_uncompressed_size;
+ }
+ else
+ {
+ decompress = FALSE;
+ buffer_size = compressed_size;
+ }
+ buffer = (bfd_byte *) bfd_alloc (abfd, buffer_size);
+ if (buffer == NULL)
+ return 0;
+
+ if (compressed)
+ {
+ sec->size = orig_uncompressed_size;
+ if (decompress)
+ {
+ if (!decompress_contents (uncompressed_buffer
+ + orig_compression_header_size,
+ zlib_size, buffer, buffer_size))
+ {
+ bfd_set_error (bfd_error_bad_value);
+ bfd_release (abfd, buffer);
+ return 0;
+ }
+ free (uncompressed_buffer);
+ sec->contents = buffer;
+ sec->compress_status = COMPRESS_SECTION_DONE;
+ return orig_uncompressed_size;
+ }
+ else
+ {
+ bfd_update_compression_header (abfd, buffer, sec);
+ memmove (buffer + header_size,
+ uncompressed_buffer + orig_compression_header_size,
+ zlib_size);
+ }
}
+ else
+ {
+ if (compress ((Bytef*) buffer + header_size,
+ &compressed_size,
+ (const Bytef*) uncompressed_buffer,
+ uncompressed_size) != Z_OK)
+ {
+ bfd_release (abfd, buffer);
+ bfd_set_error (bfd_error_bad_value);
+ return 0;
+ }
- /* Write the zlib header. In this case, it should be "ZLIB" followed
- by the uncompressed section size, 8 bytes in big-endian order. */
- memcpy (compressed_buffer, "ZLIB", 4);
- compressed_buffer[11] = uncompressed_size; uncompressed_size >>= 8;
- compressed_buffer[10] = uncompressed_size; uncompressed_size >>= 8;
- compressed_buffer[9] = uncompressed_size; uncompressed_size >>= 8;
- compressed_buffer[8] = uncompressed_size; uncompressed_size >>= 8;
- compressed_buffer[7] = uncompressed_size; uncompressed_size >>= 8;
- compressed_buffer[6] = uncompressed_size; uncompressed_size >>= 8;
- compressed_buffer[5] = uncompressed_size; uncompressed_size >>= 8;
- compressed_buffer[4] = uncompressed_size;
- compressed_size += 12;
-
- /* Free the uncompressed contents if we compress in place. */
- if (uncompressed_buffer == sec->contents)
- free (uncompressed_buffer);
-
- sec->contents = compressed_buffer;
+ compressed_size += header_size;
+ /* PR binutils/18087: If compression didn't make the section smaller,
+ just keep it uncompressed. */
+ if (compressed_size < uncompressed_size)
+ bfd_update_compression_header (abfd, buffer, sec);
+ else
+ {
+ /* NOTE: There is a small memory leak here since
+ uncompressed_buffer is malloced and won't be freed. */
+ bfd_release (abfd, buffer);
+ sec->contents = uncompressed_buffer;
+ sec->compress_status = COMPRESS_SECTION_NONE;
+ return uncompressed_size;
+ }
+ }
+
+ free (uncompressed_buffer);
+ sec->contents = buffer;
sec->size = compressed_size;
sec->compress_status = COMPRESS_SECTION_DONE;
- return TRUE;
-#endif /* HAVE_ZLIB_H */
+ return uncompressed_size;
}
/*
return @var{*ptr} with memory malloc'd by this function.
Return @code{TRUE} if the full section contents is retrieved
- successfully.
+ successfully. If the section has no contents then this function
+ returns @code{TRUE} but @var{*ptr} is set to NULL.
*/
bfd_boolean
{
bfd_size_type sz;
bfd_byte *p = *ptr;
-#ifdef HAVE_ZLIB_H
bfd_boolean ret;
bfd_size_type save_size;
bfd_size_type save_rawsize;
bfd_byte *compressed_buffer;
-#endif
+ unsigned int compression_header_size;
if (abfd->direction != write_direction && sec->rawsize != 0)
sz = sec->rawsize;
else
sz = sec->size;
if (sz == 0)
- return TRUE;
+ {
+ *ptr = NULL;
+ return TRUE;
+ }
switch (sec->compress_status)
{
{
p = (bfd_byte *) bfd_malloc (sz);
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: %B(%A) is too large (%#lx bytes)"),
+ abfd, sec, (long) sz);
return FALSE;
+ }
}
+
if (!bfd_get_section_contents (abfd, sec, p, 0, sz))
{
if (*ptr != p)
return TRUE;
case DECOMPRESS_SECTION_SIZED:
-#ifndef HAVE_ZLIB_H
- bfd_set_error (bfd_error_invalid_operation);
- return FALSE;
-#else
/* Read in the full compressed section contents. */
compressed_buffer = (bfd_byte *) bfd_malloc (sec->compressed_size);
if (compressed_buffer == NULL)
if (p == NULL)
goto fail_compressed;
- if (!decompress_contents (compressed_buffer, sec->compressed_size, p, sz))
+ 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;
+ if (!decompress_contents (compressed_buffer + compression_header_size,
+ sec->compressed_size - compression_header_size, p, sz))
{
bfd_set_error (bfd_error_bad_value);
if (p != *ptr)
free (compressed_buffer);
*ptr = p;
return TRUE;
-#endif
case COMPRESS_SECTION_DONE:
+ if (sec->contents == NULL)
+ return FALSE;
if (p == NULL)
{
p = (bfd_byte *) bfd_malloc (sz);
return FALSE;
*ptr = p;
}
- memcpy (p, sec->contents, sz);
+ /* PR 17512; file: 5bc29788. */
+ if (p != sec->contents)
+ memcpy (p, sec->contents, sz);
return TRUE;
default:
sec->flags |= SEC_IN_MEMORY;
}
-
/*
FUNCTION
- bfd_is_section_compressed
+ bfd_is_section_compressed_with_header
SYNOPSIS
- bfd_boolean bfd_is_section_compressed
- (bfd *abfd, asection *section);
+ bfd_boolean bfd_is_section_compressed_with_header
+ (bfd *abfd, asection *section,
+ int *compression_header_size_p,
+ bfd_size_type *uncompressed_size_p);
DESCRIPTION
- Return @code{TRUE} if @var{section} is compressed.
+ Return @code{TRUE} if @var{section} is compressed. Compression
+ header size is returned in @var{compression_header_size_p} and
+ uncompressed size is returned in @var{uncompressed_size_p}. If
+ compression is unsupported, compression header size is returned
+ with -1 and uncompressed size is returned with 0.
*/
bfd_boolean
-bfd_is_section_compressed (bfd *abfd, sec_ptr sec)
+bfd_is_section_compressed_with_header (bfd *abfd, sec_ptr sec,
+ int *compression_header_size_p,
+ bfd_size_type *uncompressed_size_p)
{
- bfd_byte compressed_buffer [12];
+ bfd_byte header[MAX_COMPRESSION_HEADER_SIZE];
+ int compression_header_size;
+ int header_size;
unsigned int saved = sec->compress_status;
bfd_boolean compressed;
+ 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 zlib header. In this case, it should be "ZLIB" followed
- by the uncompressed section size, 8 bytes in big-endian order. */
- compressed = (bfd_get_section_contents (abfd, sec, compressed_buffer, 0, 12)
- && CONST_STRNEQ ((char*) compressed_buffer, "ZLIB"));
+ /* 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 = CONST_STRNEQ ((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,
+ uncompressed_size_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
+ bfd_boolean bfd_is_section_compressed
+ (bfd *abfd, asection *section);
+
+DESCRIPTION
+ Return @code{TRUE} if @var{section} is compressed.
+*/
+
+bfd_boolean
+bfd_is_section_compressed (bfd *abfd, sec_ptr sec)
+{
+ int compression_header_size;
+ bfd_size_type uncompressed_size;
+ return (bfd_is_section_compressed_with_header (abfd, sec,
+ &compression_header_size,
+ &uncompressed_size)
+ && compression_header_size >= 0
+ && uncompressed_size > 0);
+}
+
/*
FUNCTION
bfd_init_section_decompress_status
DECOMPRESS_SECTION_SIZED.
Return @code{FALSE} if the section is not a valid compressed
- section or zlib is not installed on this machine. Otherwise,
- return @code{TRUE}.
+ section. Otherwise, return @code{TRUE}.
*/
bfd_boolean
-bfd_init_section_decompress_status (bfd *abfd ATTRIBUTE_UNUSED,
- sec_ptr sec ATTRIBUTE_UNUSED)
+bfd_init_section_decompress_status (bfd *abfd, sec_ptr sec)
{
-#ifndef HAVE_ZLIB_H
- bfd_set_error (bfd_error_invalid_operation);
- return FALSE;
-#else
- bfd_byte compressed_buffer [12];
+ bfd_byte header[MAX_COMPRESSION_HEADER_SIZE];
+ int compression_header_size;
+ int header_size;
bfd_size_type uncompressed_size;
+ 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, compressed_buffer, 0, 12))
+ || !bfd_get_section_contents (abfd, sec, header, 0, header_size))
{
bfd_set_error (bfd_error_invalid_operation);
return FALSE;
}
- /* Read the zlib header. In this case, it should be "ZLIB" followed
- by the uncompressed section size, 8 bytes in big-endian order. */
- if (! CONST_STRNEQ ((char*) compressed_buffer, "ZLIB"))
+ 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 (! CONST_STRNEQ ((char*) header, "ZLIB"))
+ {
+ bfd_set_error (bfd_error_wrong_format);
+ return FALSE;
+ }
+ uncompressed_size = bfd_getb64 (header + 4);
+ }
+ else if (!bfd_check_compression_header (abfd, header, sec,
+ &uncompressed_size))
{
bfd_set_error (bfd_error_wrong_format);
return FALSE;
}
- uncompressed_size = compressed_buffer[4]; uncompressed_size <<= 8;
- uncompressed_size += compressed_buffer[5]; uncompressed_size <<= 8;
- uncompressed_size += compressed_buffer[6]; uncompressed_size <<= 8;
- uncompressed_size += compressed_buffer[7]; uncompressed_size <<= 8;
- uncompressed_size += compressed_buffer[8]; uncompressed_size <<= 8;
- uncompressed_size += compressed_buffer[9]; uncompressed_size <<= 8;
- uncompressed_size += compressed_buffer[10]; uncompressed_size <<= 8;
- uncompressed_size += compressed_buffer[11];
-
sec->compressed_size = sec->size;
sec->size = uncompressed_size;
sec->compress_status = DECOMPRESS_SECTION_SIZED;
return TRUE;
-#endif
}
/*
compressed size and set compress_status to COMPRESS_SECTION_DONE.
Return @code{FALSE} if the section is not a valid compressed
- section or zlib is not installed on this machine. Otherwise,
- return @code{TRUE}.
+ section. Otherwise, return @code{TRUE}.
*/
bfd_boolean
-bfd_init_section_compress_status (bfd *abfd ATTRIBUTE_UNUSED,
- sec_ptr sec ATTRIBUTE_UNUSED)
+bfd_init_section_compress_status (bfd *abfd, sec_ptr sec)
{
-#ifndef HAVE_ZLIB_H
- bfd_set_error (bfd_error_invalid_operation);
- return FALSE;
-#else
bfd_size_type uncompressed_size;
bfd_byte *uncompressed_buffer;
bfd_boolean ret;
0, uncompressed_size))
ret = FALSE;
else
- ret = bfd_compress_section_contents (abfd, sec,
- uncompressed_buffer,
- uncompressed_size);
+ {
+ uncompressed_size = bfd_compress_section_contents (abfd, sec,
+ uncompressed_buffer,
+ uncompressed_size);
+ ret = uncompressed_size != 0;
+ }
- free (uncompressed_buffer);
return ret;
-#endif
+}
+
+/*
+FUNCTION
+ bfd_compress_section
+
+SYNOPSIS
+ bfd_boolean 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}.
+*/
+
+bfd_boolean
+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;
+ }
+
+ /* Compress it. */
+ return bfd_compress_section_contents (abfd, sec, uncompressed_buffer,
+ uncompressed_size) != 0;
}