diff options
Diffstat (limited to 'libelf/elf_getarsym.c')
-rw-r--r-- | libelf/elf_getarsym.c | 278 |
1 files changed, 278 insertions, 0 deletions
diff --git a/libelf/elf_getarsym.c b/libelf/elf_getarsym.c new file mode 100644 index 0000000..e6ecaad --- /dev/null +++ b/libelf/elf_getarsym.c @@ -0,0 +1,278 @@ +/* Return symbol table of archive. + Copyright (C) 1998, 1999, 2000, 2002, 2005 Red Hat, Inc. + This file is part of Red Hat elfutils. + Written by Ulrich Drepper <drepper@redhat.com>, 1998. + + 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 + <http://www.openinventionnetwork.com>. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#include <assert.h> +#include <byteswap.h> +#include <endian.h> +#include <errno.h> +#include <stdint.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> + +#include <system.h> +#include <dl-hash.h> +#include "libelfP.h" + + +Elf_Arsym * +elf_getarsym (elf, ptr) + Elf *elf; + size_t *ptr; +{ + if (elf->kind != ELF_K_AR) + { + /* This is no archive. */ + __libelf_seterrno (ELF_E_NO_ARCHIVE); + return NULL; + } + + if (ptr != NULL) + /* In case of an error or when we know the value store the expected + value now. Doing this allows us easier exits in an error case. */ + *ptr = elf->state.ar.ar_sym_num; + + if (elf->state.ar.ar_sym == (Elf_Arsym *) -1l) + { + /* There is no index. */ + __libelf_seterrno (ELF_E_NO_INDEX); + return NULL; + } + + Elf_Arsym *result = elf->state.ar.ar_sym; + if (result == NULL) + { + /* We have not yet read the index. */ + rwlock_wrlock (elf->lock); + + /* In case we find no index remember this for the next call. */ + elf->state.ar.ar_sym = (Elf_Arsym *) -1l; + + struct ar_hdr *index_hdr; + if (elf->map_address == NULL) + { + /* We must read index from the file. */ + assert (elf->fildes != -1); + if (pread_retry (elf->fildes, &elf->state.ar.ar_hdr, + sizeof (struct ar_hdr), elf->start_offset + SARMAG) + != sizeof (struct ar_hdr)) + { + /* It is not possible to read the index. Maybe it does not + exist. */ + __libelf_seterrno (ELF_E_READ_ERROR); + goto out; + } + + index_hdr = &elf->state.ar.ar_hdr; + } + else + { + if (SARMAG + sizeof (struct ar_hdr) > elf->maximum_size) + { + /* There is no room for the full archive. */ + __libelf_seterrno (ELF_E_NO_INDEX); + goto out; + } + + index_hdr = (struct ar_hdr *) (elf->map_address + + elf->start_offset + SARMAG); + } + + /* Now test whether this really is an archive. */ + if (memcmp (index_hdr->ar_fmag, ARFMAG, 2) != 0) + { + /* Invalid magic bytes. */ + __libelf_seterrno (ELF_E_ARCHIVE_FMAG); + goto out; + } + + /* Now test whether this is the index. It is denoted by the + name being "/ ". + XXX This is not entirely true. There are some more forms. + Which of them shall we handle? */ + if (memcmp (index_hdr->ar_name, "/ ", 16) != 0) + { + /* If the index is not the first entry, there is no index. + + XXX Is this true? */ + __libelf_seterrno (ELF_E_NO_INDEX); + goto out; + } + + /* We have an archive. The first word in there is the number of + entries in the table. */ + uint32_t n; + if (elf->map_address == NULL) + { + if (pread_retry (elf->fildes, &n, sizeof (n), + elf->start_offset + SARMAG + sizeof (struct ar_hdr)) + != sizeof (n)) + { + /* Cannot read the number of entries. */ + __libelf_seterrno (ELF_E_NO_INDEX); + goto out; + } + } + else + n = *(uint32_t *) (elf->map_address + elf->start_offset + + SARMAG + sizeof (struct ar_hdr)); + + if (__BYTE_ORDER == __LITTLE_ENDIAN) + n = bswap_32 (n); + + /* Now we can perform some first tests on whether all the data + needed for the index is available. */ + char tmpbuf[17]; + memcpy (tmpbuf, index_hdr->ar_size, 10); + tmpbuf[10] = '\0'; + size_t index_size = atol (tmpbuf); + + if (SARMAG + sizeof (struct ar_hdr) + index_size > elf->maximum_size + || n * sizeof (uint32_t) > index_size) + { + /* This index table cannot be right since it does not fit into + the file. */ + __libelf_seterrno (ELF_E_NO_INDEX); + goto out; + } + + /* Now we can allocate the arrays needed to store the index. */ + size_t ar_sym_len = (n + 1) * sizeof (Elf_Arsym); + elf->state.ar.ar_sym = (Elf_Arsym *) malloc (ar_sym_len); + if (elf->state.ar.ar_sym != NULL) + { + uint32_t *file_data; + char *str_data; + + if (elf->map_address == NULL) + { + file_data = (uint32_t *) alloca (n * sizeof (uint32_t)); + + ar_sym_len += index_size - n * sizeof (uint32_t); + Elf_Arsym *newp = (Elf_Arsym *) realloc (elf->state.ar.ar_sym, + ar_sym_len); + if (newp == NULL) + { + free (elf->state.ar.ar_sym); + elf->state.ar.ar_sym = NULL; + __libelf_seterrno (ELF_E_NOMEM); + goto out; + } + elf->state.ar.ar_sym = newp; + + char *new_str = (char *) (elf->state.ar.ar_sym + n + 1); + + /* Now read the data from the file. */ + if ((size_t) pread_retry (elf->fildes, file_data, + n * sizeof (uint32_t), + elf->start_offset + SARMAG + + sizeof (struct ar_hdr) + + sizeof (uint32_t)) + != n * sizeof (uint32_t) + || ((size_t) pread_retry (elf->fildes, new_str, + index_size - n * sizeof (uint32_t), + elf->start_offset + + SARMAG + sizeof (struct ar_hdr) + + (n + 1) * sizeof (uint32_t)) + != index_size - n * sizeof (uint32_t))) + { + /* We were not able to read the data. */ + free (elf->state.ar.ar_sym); + elf->state.ar.ar_sym = NULL; + __libelf_seterrno (ELF_E_NO_INDEX); + goto out; + } + + str_data = (char *) new_str; + } + else + { + file_data = (uint32_t *) (elf->map_address + elf->start_offset + + SARMAG + sizeof (struct ar_hdr) + + sizeof (uint32_t)); + str_data = (char *) &file_data[n]; + } + + /* Now we can build the data structure. */ + Elf_Arsym *arsym = elf->state.ar.ar_sym; + for (size_t cnt = 0; cnt < n; ++cnt) + { + arsym[cnt].as_name = str_data; + if (__BYTE_ORDER == __LITTLE_ENDIAN) + arsym[cnt].as_off = bswap_32 (file_data[cnt]); + else + arsym[cnt].as_off = file_data[cnt]; + arsym[cnt].as_hash = _dl_elf_hash (str_data); + str_data = rawmemchr (str_data, '\0') + 1; + } + /* At the end a special entry. */ + arsym[n].as_name = NULL; + arsym[n].as_off = 0; + arsym[n].as_hash = ~0UL; + + /* Tell the caller how many entries we have. */ + elf->state.ar.ar_sym_num = n + 1; + } + + result = elf->state.ar.ar_sym; + + out: + rwlock_unlock (elf->lock); + } + + if (ptr != NULL) + *ptr = elf->state.ar.ar_sym_num; + + return result; +} |