1cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng/* Get note information at the supplied offset. 2cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Copyright (C) 2007 Red Hat, Inc. 3cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng This file is part of Red Hat elfutils. 4cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 5cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Red Hat elfutils is free software; you can redistribute it and/or modify 6cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng it under the terms of the GNU General Public License as published by the 7cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Free Software Foundation; version 2 of the License. 8cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 9cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Red Hat elfutils is distributed in the hope that it will be useful, but 10cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng WITHOUT ANY WARRANTY; without even the implied warranty of 11cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng General Public License for more details. 13cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 14cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng You should have received a copy of the GNU General Public License along 15cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng with Red Hat elfutils; if not, write to the Free Software Foundation, 16cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. 17cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 18cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng In addition, as a special exception, Red Hat, Inc. gives You the 19cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng additional right to link the code of Red Hat elfutils with code licensed 20cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng under any Open Source Initiative certified open source license 21cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng (http://www.opensource.org/licenses/index.php) which requires the 22cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng distribution of source code with any binary distribution and to 23cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng distribute linked combinations of the two. Non-GPL Code permitted under 24cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng this exception must only link to the code of Red Hat elfutils through 25cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng those well defined interfaces identified in the file named EXCEPTION 26cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng found in the source code files (the "Approved Interfaces"). The files 27cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng of Non-GPL Code may instantiate templates or use macros or inline 28cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng functions from the Approved Interfaces without causing the resulting 29cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng work to be covered by the GNU General Public License. Only Red Hat, 30cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Inc. may make changes or additions to the list of Approved Interfaces. 31cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Red Hat's grant of this exception is conditioned upon your not adding 32cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng any new exceptions. If you wish to add a new Approved Interface or 33cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng exception, please contact Red Hat. You must obey the GNU General Public 34cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng License in all respects for all of the Red Hat elfutils code and other 35cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng code used in conjunction with Red Hat elfutils except the Non-GPL Code 36cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng covered by this exception. If you modify this file, you may extend this 37cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng exception to your version of the file, but you are not obligated to do 38cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng so. If you do not wish to provide this exception without modification, 39cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng you must delete this exception statement from your version and license 40cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng this file solely under the GPL without exception. 41cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 42cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Red Hat elfutils is an included package of the Open Invention Network. 43cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng An included package of the Open Invention Network is a package for which 44cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Open Invention Network licensees cross-license their patents. No patent 45cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng license is granted, either expressly or impliedly, by designation as an 46cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng included package. Should you wish to participate in the Open Invention 47cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Network licensing program, please visit www.openinventionnetwork.com 48cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng <http://www.openinventionnetwork.com>. */ 49cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 50cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng#ifdef HAVE_CONFIG_H 51cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng# include <config.h> 52cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng#endif 53cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 54cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng#include <assert.h> 55cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng#include <gelf.h> 56cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng#include <string.h> 57cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 58cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng#include "libelfP.h" 59cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 60cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Chengsize_t 61cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Chenggelf_getnote (data, offset, result, name_offset, desc_offset) 62cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng Elf_Data *data; 63cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng size_t offset; 64cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng GElf_Nhdr *result; 65cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng size_t *name_offset; 66cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng size_t *desc_offset; 67cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng{ 68cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng if (data == NULL) 69cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng return 0; 70cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 71cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng if (unlikely (data->d_type != ELF_T_NHDR)) 72cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng { 73cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng __libelf_seterrno (ELF_E_INVALID_HANDLE); 74cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng return 0; 75cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng } 76cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 77cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng /* It's easy to handle this type. It has the same size for 32 and 78cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 64 bit objects. */ 79cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng assert (sizeof (GElf_Nhdr) == sizeof (Elf32_Nhdr)); 80cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng assert (sizeof (GElf_Nhdr) == sizeof (Elf64_Nhdr)); 81cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 82cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng rwlock_rdlock (((Elf_Data_Scn *) data)->s->elf->lock); 83cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 84cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng /* The data is already in the correct form. Just make sure the 85cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng offset is OK. */ 86cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng if (unlikely (offset + sizeof (GElf_Nhdr) > data->d_size)) 87cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng { 88cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng __libelf_seterrno (ELF_E_OFFSET_RANGE); 89cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng offset = 0; 90cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng } 91cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng else 92cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng { 93cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng const GElf_Nhdr *n = data->d_buf + offset; 94cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng offset += sizeof *n; 95cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 96cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng GElf_Word namesz = NOTE_ALIGN (n->n_namesz); 97cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng GElf_Word descsz = NOTE_ALIGN (n->n_descsz); 98cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 99cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng if (unlikely (data->d_size - offset < namesz)) 100cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng offset = 0; 101cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng else 102cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng { 103cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng *name_offset = offset; 104cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng offset += namesz; 105cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng if (unlikely (data->d_size - offset < descsz)) 106cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng offset = 0; 107cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng else 108cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng { 109cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng *desc_offset = offset; 110cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng offset += descsz; 111cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng *result = *n; 112cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng } 113cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng } 114cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng } 115cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 116cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng rwlock_unlock (((Elf_Data_Scn *) data)->s->elf->lock); 117cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng 118cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng return offset; 119cc6695e2684ce93cdf8bd2da63d55d2cf49ff076Ben Cheng} 120