/* 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 "../libelf/libelfP.h" #undef _ #include "libdwflP.h" #include #if !USE_ZLIB # define __libdw_gunzip(...) false #endif #if !USE_BZLIB # define __libdw_bunzip2(...) false #endif #if !USE_LZMA # define __libdw_unlzma(...) false #endif /* Consumes and replaces *ELF only on success. */ static Dwfl_Error decompress (int fd __attribute__ ((unused)), Elf **elf) { Dwfl_Error error = DWFL_E_BADELF; void *buffer = NULL; size_t size = 0; #if USE_ZLIB || USE_BZLIB || USE_LZMA const off64_t offset = (*elf)->start_offset; void *const mapped = ((*elf)->map_address == NULL ? NULL : (*elf)->map_address + offset); const size_t mapped_size = (*elf)->maximum_size; if (mapped_size == 0) return error; error = __libdw_gunzip (fd, offset, mapped, mapped_size, &buffer, &size); if (error == DWFL_E_BADELF) error = __libdw_bunzip2 (fd, offset, mapped, mapped_size, &buffer, &size); if (error == DWFL_E_BADELF) error = __libdw_unlzma (fd, offset, mapped, mapped_size, &buffer, &size); #endif if (error == DWFL_E_NOERROR) { if (unlikely (size == 0)) { error = DWFL_E_BADELF; free (buffer); } else { Elf *memelf = elf_memory (buffer, size); if (memelf == NULL) { error = DWFL_E_LIBELF; free (buffer); } else { memelf->flags |= ELF_F_MALLOCED; elf_end (*elf); *elf = memelf; } } } else free (buffer); return error; } static Dwfl_Error what_kind (int fd, Elf **elfp, Elf_Kind *kind, bool *close_fd) { Dwfl_Error error = DWFL_E_NOERROR; *kind = elf_kind (*elfp); if (unlikely (*kind == ELF_K_NONE)) { if (unlikely (*elfp == NULL)) error = DWFL_E_LIBELF; else { error = decompress (fd, elfp); if (error == DWFL_E_NOERROR) { *close_fd = true; *kind = elf_kind (*elfp); } } } return error; } Dwfl_Error internal_function __libdw_open_file (int *fdp, Elf **elfp, bool close_on_fail, bool archive_ok) { bool close_fd = false; Elf *elf = elf_begin (*fdp, ELF_C_READ_MMAP_PRIVATE, NULL); Elf_Kind kind; Dwfl_Error error = what_kind (*fdp, &elf, &kind, &close_fd); if (error == DWFL_E_BADELF) { /* It's not an ELF file or a compressed file. See if it's an image with a header preceding the real file. */ off64_t offset = elf->start_offset; error = __libdw_image_header (*fdp, &offset, (elf->map_address == NULL ? NULL : elf->map_address + offset), elf->maximum_size); if (error == DWFL_E_NOERROR) { /* Pure evil. libelf needs some better interfaces. */ elf->kind = ELF_K_AR; elf->state.ar.elf_ar_hdr.ar_name = "libdwfl is faking you out"; elf->state.ar.elf_ar_hdr.ar_size = elf->maximum_size - offset; elf->state.ar.offset = offset - sizeof (struct ar_hdr); Elf *subelf = elf_begin (-1, ELF_C_READ_MMAP_PRIVATE, elf); elf->kind = ELF_K_NONE; if (unlikely (subelf == NULL)) error = DWFL_E_LIBELF; else { subelf->parent = NULL; subelf->flags |= elf->flags & (ELF_F_MMAPPED | ELF_F_MALLOCED); elf->flags &= ~(ELF_F_MMAPPED | ELF_F_MALLOCED); elf_end (elf); elf = subelf; error = what_kind (*fdp, &elf, &kind, &close_fd); } } } if (error == DWFL_E_NOERROR && kind != ELF_K_ELF && !(archive_ok && kind == ELF_K_AR)) error = DWFL_E_BADELF; if (error != DWFL_E_NOERROR) { elf_end (elf); elf = NULL; } if (error == DWFL_E_NOERROR ? close_fd : close_on_fail) { close (*fdp); *fdp = -1; } *elfp = elf; return error; }