/* Decompression support for libdwfl: zlib (gzip) and/or bzlib (bzip2). Copyright (C) 2009 Red Hat, Inc. This file is part of Red Hat elfutils. Red Hat elfutils 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; version 2 of the License. Red Hat elfutils 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 Red Hat elfutils; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. In addition, as a special exception, Red Hat, Inc. gives You the additional right to link the code of Red Hat elfutils with code licensed under any Open Source Initiative certified open source license (http://www.opensource.org/licenses/index.php) which requires the distribution of source code with any binary distribution and to distribute linked combinations of the two. Non-GPL Code permitted under this exception must only link to the code of Red Hat elfutils through those well defined interfaces identified in the file named EXCEPTION found in the source code files (the "Approved Interfaces"). The files of Non-GPL Code may instantiate templates or use macros or inline functions from the Approved Interfaces without causing the resulting work to be covered by the GNU General Public License. Only Red Hat, Inc. may make changes or additions to the list of Approved Interfaces. Red Hat's grant of this exception is conditioned upon your not adding any new exceptions. If you wish to add a new Approved Interface or exception, please contact Red Hat. You must obey the GNU General Public License in all respects for all of the Red Hat elfutils code and other code used in conjunction with Red Hat elfutils except the Non-GPL Code covered by this exception. If you modify this file, you may extend this exception to your version of the file, but you are not obligated to do so. If you do not wish to provide this exception without modification, you must delete this exception statement from your version and license this file solely under the GPL without exception. Red Hat elfutils is an included package of the Open Invention Network. An included package of the Open Invention Network is a package for which Open Invention Network licensees cross-license their patents. No patent license is granted, either expressly or impliedly, by designation as an included package. Should you wish to participate in the Open Invention Network licensing program, please visit www.openinventionnetwork.com . */ #include "libdwflP.h" #include "system.h" #include #ifdef LZMA # define USE_INFLATE 1 # include # define unzip __libdw_unlzma # define DWFL_E_ZLIB DWFL_E_LZMA # define MAGIC "\xFD" "7zXZ\0" /* XZ file format. */ # define MAGIC2 "\x5d\0" /* Raw LZMA format. */ # define Z(what) LZMA_##what # define LZMA_ERRNO LZMA_PROG_ERROR # define z_stream lzma_stream # define inflateInit(z) lzma_auto_decoder (z, 1 << 30, 0) # define do_inflate(z) lzma_code (z, LZMA_RUN) # define inflateEnd(z) lzma_end (z) #elif defined BZLIB # define USE_INFLATE 1 # include # define unzip __libdw_bunzip2 # define DWFL_E_ZLIB DWFL_E_BZLIB # define MAGIC "BZh" # define Z(what) BZ_##what # define BZ_ERRNO BZ_IO_ERROR # define z_stream bz_stream # define inflateInit(z) BZ2_bzDecompressInit (z, 0, 0) # define do_inflate(z) BZ2_bzDecompress (z) # define inflateEnd(z) BZ2_bzDecompressEnd (z) #else # define USE_INFLATE 0 # define crc32 loser_crc32 # include # define unzip __libdw_gunzip # define MAGIC "\037\213" # define Z(what) Z_##what #endif #define READ_SIZE (1 << 20) /* If this is not a compressed image, return DWFL_E_BADELF. If we uncompressed it into *WHOLE, *WHOLE_SIZE, return DWFL_E_NOERROR. Otherwise return an error for bad compressed data or I/O failure. If we return an error after reading the first part of the file, leave that portion malloc'd in *WHOLE, *WHOLE_SIZE. If *WHOLE is not null on entry, we'll use it in lieu of repeating a read. */ Dwfl_Error internal_function unzip (int fd, off64_t start_offset, void *mapped, size_t mapped_size, void **whole, size_t *whole_size) { void *buffer = NULL; size_t size = 0; inline bool bigger_buffer (size_t start) { size_t more = size ? size * 2 : start; char *b = realloc (buffer, more); while (unlikely (b == NULL) && more >= size + 1024) b = realloc (buffer, more -= 1024); if (unlikely (b == NULL)) return false; buffer = b; size = more; return true; } inline void smaller_buffer (size_t end) { buffer = realloc (buffer, end) ?: end == 0 ? NULL : buffer; size = end; } void *input_buffer = NULL; off_t input_pos = 0; inline Dwfl_Error fail (Dwfl_Error failure) { if (input_pos == (off_t) mapped_size) *whole = input_buffer; else { free (input_buffer); *whole = NULL; } free (buffer); return failure; } inline Dwfl_Error zlib_fail (int result) { switch (result) { case Z (MEM_ERROR): return fail (DWFL_E_NOMEM); case Z (ERRNO): return fail (DWFL_E_ERRNO); default: return fail (DWFL_E_ZLIB); } } if (mapped == NULL) { if (*whole == NULL) { input_buffer = malloc (READ_SIZE); if (unlikely (input_buffer == NULL)) return DWFL_E_NOMEM; ssize_t n = pread_retry (fd, input_buffer, READ_SIZE, start_offset); if (unlikely (n < 0)) return zlib_fail (Z (ERRNO)); input_pos = n; mapped = input_buffer; mapped_size = n; } else { input_buffer = *whole; input_pos = mapped_size = *whole_size; } } #define NOMAGIC(magic) \ (mapped_size <= sizeof magic || memcmp (mapped, magic, sizeof magic - 1)) /* First, look at the header. */ if (NOMAGIC (MAGIC) #ifdef MAGIC2 && NOMAGIC (MAGIC2) #endif ) /* Not a compressed file. */ return DWFL_E_BADELF; #if USE_INFLATE /* This style actually only works with bzlib and liblzma. The stupid zlib interface has nothing to grok the gzip file headers except the slow gzFile interface. */ z_stream z = { .next_in = mapped, .avail_in = mapped_size }; int result = inflateInit (&z); if (result != Z (OK)) { inflateEnd (&z); return zlib_fail (result); } do { if (z.avail_in == 0 && input_buffer != NULL) { ssize_t n = pread_retry (fd, input_buffer, READ_SIZE, start_offset + input_pos); if (unlikely (n < 0)) { inflateEnd (&z); return zlib_fail (Z (ERRNO)); } z.next_in = input_buffer; z.avail_in = n; input_pos += n; } if (z.avail_out == 0) { ptrdiff_t pos = (void *) z.next_out - buffer; if (!bigger_buffer (z.avail_in)) { result = Z (MEM_ERROR); break; } z.next_out = buffer + pos; z.avail_out = size - pos; } } while ((result = do_inflate (&z)) == Z (OK)); #ifdef BZLIB uint64_t total_out = (((uint64_t) z.total_out_hi32 << 32) | z.total_out_lo32); smaller_buffer (total_out); #else smaller_buffer (z.total_out); #endif inflateEnd (&z); if (result != Z (STREAM_END)) return zlib_fail (result); #else /* gzip only. */ /* Let the decompression library read the file directly. */ gzFile zf; Dwfl_Error open_stream (void) { int d = dup (fd); if (unlikely (d < 0)) return DWFL_E_BADELF; if (start_offset != 0) { off64_t off = lseek (d, start_offset, SEEK_SET); if (off != start_offset) { close (d); return DWFL_E_BADELF; } } zf = gzdopen (d, "r"); if (unlikely (zf == NULL)) { close (d); return zlib_fail (Z (MEM_ERROR)); } /* From here on, zlib will close D. */ return DWFL_E_NOERROR; } Dwfl_Error result = open_stream (); if (result == DWFL_E_NOERROR && gzdirect (zf)) { gzclose (zf); return fail (DWFL_E_BADELF); } if (result != DWFL_E_NOERROR) return fail (result); ptrdiff_t pos = 0; while (1) { if (!bigger_buffer (1024)) { gzclose (zf); return zlib_fail (Z (MEM_ERROR)); } int n = gzread (zf, buffer + pos, size - pos); if (n < 0) { int code; gzerror (zf, &code); gzclose (zf); return zlib_fail (code); } if (n == 0) break; pos += n; } gzclose (zf); smaller_buffer (pos); #endif free (input_buffer); *whole = buffer; *whole_size = size; return DWFL_E_NOERROR; }