The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 1 | /* Compute simple checksum from permanent parts of the ELF file. |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 2 | Copyright (C) 2002, 2003, 2004, 2005 Red Hat, Inc. |
| 3 | This file is part of Red Hat elfutils. |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 4 | Written by Ulrich Drepper <drepper@redhat.com>, 2002. |
| 5 | |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 6 | Red Hat elfutils is free software; you can redistribute it and/or modify |
| 7 | it under the terms of the GNU General Public License as published by the |
| 8 | Free Software Foundation; version 2 of the License. |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 9 | |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 10 | Red Hat elfutils is distributed in the hope that it will be useful, but |
| 11 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | General Public License for more details. |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 14 | |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 15 | You should have received a copy of the GNU General Public License along |
| 16 | with Red Hat elfutils; if not, write to the Free Software Foundation, |
| 17 | Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. |
| 18 | |
| 19 | In addition, as a special exception, Red Hat, Inc. gives You the |
| 20 | additional right to link the code of Red Hat elfutils with code licensed |
| 21 | under any Open Source Initiative certified open source license |
| 22 | (http://www.opensource.org/licenses/index.php) which requires the |
| 23 | distribution of source code with any binary distribution and to |
| 24 | distribute linked combinations of the two. Non-GPL Code permitted under |
| 25 | this exception must only link to the code of Red Hat elfutils through |
| 26 | those well defined interfaces identified in the file named EXCEPTION |
| 27 | found in the source code files (the "Approved Interfaces"). The files |
| 28 | of Non-GPL Code may instantiate templates or use macros or inline |
| 29 | functions from the Approved Interfaces without causing the resulting |
| 30 | work to be covered by the GNU General Public License. Only Red Hat, |
| 31 | Inc. may make changes or additions to the list of Approved Interfaces. |
| 32 | Red Hat's grant of this exception is conditioned upon your not adding |
| 33 | any new exceptions. If you wish to add a new Approved Interface or |
| 34 | exception, please contact Red Hat. You must obey the GNU General Public |
| 35 | License in all respects for all of the Red Hat elfutils code and other |
| 36 | code used in conjunction with Red Hat elfutils except the Non-GPL Code |
| 37 | covered by this exception. If you modify this file, you may extend this |
| 38 | exception to your version of the file, but you are not obligated to do |
| 39 | so. If you do not wish to provide this exception without modification, |
| 40 | you must delete this exception statement from your version and license |
| 41 | this file solely under the GPL without exception. |
| 42 | |
| 43 | Red Hat elfutils is an included package of the Open Invention Network. |
| 44 | An included package of the Open Invention Network is a package for which |
| 45 | Open Invention Network licensees cross-license their patents. No patent |
| 46 | license is granted, either expressly or impliedly, by designation as an |
| 47 | included package. Should you wish to participate in the Open Invention |
| 48 | Network licensing program, please visit www.openinventionnetwork.com |
| 49 | <http://www.openinventionnetwork.com>. */ |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 50 | |
| 51 | #ifdef HAVE_CONFIG_H |
| 52 | # include <config.h> |
| 53 | #endif |
| 54 | |
| 55 | #include <assert.h> |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 56 | #include <endian.h> |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 57 | #include <stdbool.h> |
| 58 | #include <stddef.h> |
| 59 | #include <string.h> |
| 60 | |
| 61 | #include "gelf.h" |
| 62 | #include "libelfP.h" |
| 63 | #include "elf-knowledge.h" |
| 64 | |
| 65 | #ifndef LIBELFBITS |
| 66 | # define LIBELFBITS 32 |
| 67 | #endif |
| 68 | |
| 69 | |
| 70 | /* The SECTION_STRIP_P macro wants to call into libebl which we cannot |
| 71 | do and do not have to do here. Provide a dummy replacement. */ |
| 72 | #define ebl_debugscn_p(ebl, name) true |
| 73 | |
| 74 | |
| 75 | #define process_block(crc, data) \ |
| 76 | __libelf_crc32 (crc, data->d_buf, data->d_size) |
| 77 | |
| 78 | |
| 79 | long int |
| 80 | elfw2(LIBELFBITS,checksum) (elf) |
| 81 | Elf *elf; |
| 82 | { |
| 83 | size_t shstrndx; |
| 84 | Elf_Scn *scn; |
| 85 | long int result = 0; |
| 86 | unsigned char *ident; |
| 87 | bool same_byte_order; |
| 88 | |
| 89 | if (elf == NULL) |
| 90 | return -1l; |
| 91 | |
| 92 | /* Find the section header string table. */ |
| 93 | if (INTUSE(elf_getshstrndx) (elf, &shstrndx) < 0) |
| 94 | { |
| 95 | /* This can only happen if the ELF handle is not for real. */ |
| 96 | __libelf_seterrno (ELF_E_INVALID_HANDLE); |
| 97 | return -1l; |
| 98 | } |
| 99 | |
| 100 | /* Determine whether the byte order of the file and that of the host |
| 101 | is the same. */ |
| 102 | ident = elf->state.ELFW(elf,LIBELFBITS).ehdr->e_ident; |
| 103 | same_byte_order = ((ident[EI_DATA] == ELFDATA2LSB |
| 104 | && __BYTE_ORDER == __LITTLE_ENDIAN) |
| 105 | || (ident[EI_DATA] == ELFDATA2MSB |
| 106 | && __BYTE_ORDER == __BIG_ENDIAN)); |
| 107 | |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 108 | /* If we don't have native byte order, we will likely need to |
| 109 | convert the data with xlate functions. We do it upfront instead |
| 110 | of relocking mid-iteration. */ |
| 111 | if (!likely (same_byte_order)) |
| 112 | rwlock_wrlock (elf->lock); |
| 113 | else |
| 114 | rwlock_rdlock (elf->lock); |
| 115 | |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 116 | /* Iterate over all sections to find those which are not strippable. */ |
| 117 | scn = NULL; |
| 118 | while ((scn = INTUSE(elf_nextscn) (elf, scn)) != NULL) |
| 119 | { |
| 120 | GElf_Shdr shdr_mem; |
| 121 | GElf_Shdr *shdr; |
| 122 | Elf_Data *data; |
| 123 | |
| 124 | /* Get the section header. */ |
| 125 | shdr = INTUSE(gelf_getshdr) (scn, &shdr_mem); |
| 126 | if (shdr == NULL) |
| 127 | { |
| 128 | __libelf_seterrno (ELF_E_INVALID_SECTION_HEADER); |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 129 | result = -1l; |
| 130 | goto out; |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 131 | } |
| 132 | |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 133 | if (SECTION_STRIP_P (shdr, |
| 134 | INTUSE(elf_strptr) (elf, shstrndx, shdr->sh_name), |
| 135 | true)) |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 136 | /* The section can be stripped. Don't use it. */ |
| 137 | continue; |
| 138 | |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 139 | /* Do not look at NOBITS sections. */ |
| 140 | if (shdr->sh_type == SHT_NOBITS) |
| 141 | continue; |
| 142 | |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 143 | /* To compute the checksum we need to get to the data. For |
| 144 | repeatable results we must use the external format. The data |
| 145 | we get with 'elf'getdata' might be changed for endianess |
| 146 | reasons. Therefore we use 'elf_rawdata' if possible. But |
| 147 | this function can fail if the data was constructed by the |
| 148 | program. In this case we have to use 'elf_getdata' and |
| 149 | eventually convert the data to the external format. */ |
| 150 | data = INTUSE(elf_rawdata) (scn, NULL); |
| 151 | if (data != NULL) |
| 152 | { |
| 153 | /* The raw data is available. */ |
| 154 | result = process_block (result, data); |
| 155 | |
| 156 | /* Maybe the user added more data. These blocks cannot be |
| 157 | read using 'elf_rawdata'. Simply proceed with looking |
| 158 | for more data block with 'elf_getdata'. */ |
| 159 | } |
| 160 | |
| 161 | /* Iterate through the list of data blocks. */ |
| 162 | while ((data = INTUSE(elf_getdata) (scn, data)) != NULL) |
| 163 | /* If the file byte order is the same as the host byte order |
| 164 | process the buffer directly. If the data is just a stream |
| 165 | of bytes which the library will not convert we can use it |
| 166 | as well. */ |
| 167 | if (likely (same_byte_order) || data->d_type == ELF_T_BYTE) |
| 168 | result = process_block (result, data); |
| 169 | else |
| 170 | { |
| 171 | /* Convert the data to file byte order. */ |
| 172 | if (INTUSE(elfw2(LIBELFBITS,xlatetof)) (data, data, ident[EI_DATA]) |
| 173 | == NULL) |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 174 | { |
| 175 | result = -1l; |
| 176 | goto out; |
| 177 | } |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 178 | |
| 179 | result = process_block (result, data); |
| 180 | |
| 181 | /* And convert it back. */ |
| 182 | if (INTUSE(elfw2(LIBELFBITS,xlatetom)) (data, data, ident[EI_DATA]) |
| 183 | == NULL) |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 184 | { |
| 185 | result = -1l; |
| 186 | goto out; |
| 187 | } |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 188 | } |
| 189 | } |
| 190 | |
Ben Cheng | cc6695e | 2012-03-07 23:04:02 -0800 | [diff] [blame^] | 191 | out: |
| 192 | rwlock_unlock (elf->lock); |
The Android Open Source Project | 441f72d | 2009-03-03 19:29:28 -0800 | [diff] [blame] | 193 | return result; |
| 194 | } |
| 195 | INTDEF(elfw2(LIBELFBITS,checksum)) |