1 /* Return converted data from raw chunk of ELF file. 2 Copyright (C) 2007 Red Hat, Inc. 3 This file is part of Red Hat elfutils. 4 5 Red Hat elfutils is free software; you can redistribute it and/or modify 6 it under the terms of the GNU General Public License as published by the 7 Free Software Foundation; version 2 of the License. 8 9 Red Hat elfutils is distributed in the hope that it will be useful, but 10 WITHOUT ANY WARRANTY; without even the implied warranty of 11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 12 General Public License for more details. 13 14 You should have received a copy of the GNU General Public License along 15 with Red Hat elfutils; if not, write to the Free Software Foundation, 16 Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. 17 18 In addition, as a special exception, Red Hat, Inc. gives You the 19 additional right to link the code of Red Hat elfutils with code licensed 20 under any Open Source Initiative certified open source license 21 (http://www.opensource.org/licenses/index.php) which requires the 22 distribution of source code with any binary distribution and to 23 distribute linked combinations of the two. Non-GPL Code permitted under 24 this exception must only link to the code of Red Hat elfutils through 25 those well defined interfaces identified in the file named EXCEPTION 26 found in the source code files (the "Approved Interfaces"). The files 27 of Non-GPL Code may instantiate templates or use macros or inline 28 functions from the Approved Interfaces without causing the resulting 29 work to be covered by the GNU General Public License. Only Red Hat, 30 Inc. may make changes or additions to the list of Approved Interfaces. 31 Red Hat's grant of this exception is conditioned upon your not adding 32 any new exceptions. If you wish to add a new Approved Interface or 33 exception, please contact Red Hat. You must obey the GNU General Public 34 License in all respects for all of the Red Hat elfutils code and other 35 code used in conjunction with Red Hat elfutils except the Non-GPL Code 36 covered by this exception. If you modify this file, you may extend this 37 exception to your version of the file, but you are not obligated to do 38 so. If you do not wish to provide this exception without modification, 39 you must delete this exception statement from your version and license 40 this file solely under the GPL without exception. 41 42 Red Hat elfutils is an included package of the Open Invention Network. 43 An included package of the Open Invention Network is a package for which 44 Open Invention Network licensees cross-license their patents. No patent 45 license is granted, either expressly or impliedly, by designation as an 46 included package. Should you wish to participate in the Open Invention 47 Network licensing program, please visit www.openinventionnetwork.com 48 <http://www.openinventionnetwork.com>. */ 49 50 #ifdef HAVE_CONFIG_H 51 # include <config.h> 52 #endif 53 54 #include <assert.h> 55 #include <errno.h> 56 #include <stdlib.h> 57 #include <string.h> 58 #include <unistd.h> 59 60 #include <system.h> 61 #include "libelfP.h" 62 #include "common.h" 63 64 Elf_Data * 65 elf_getdata_rawchunk (elf, offset, size, type) 66 Elf *elf; 67 off64_t offset; 68 size_t size; 69 Elf_Type type; 70 { 71 if (unlikely (elf == NULL)) 72 return NULL; 73 74 if (unlikely (elf->kind != ELF_K_ELF)) 75 { 76 /* No valid descriptor. */ 77 __libelf_seterrno (ELF_E_INVALID_HANDLE); 78 return NULL; 79 } 80 81 if (unlikely (offset < 0 || offset + (off64_t) size < offset 82 || offset + size > elf->maximum_size)) 83 { 84 /* Invalid request. */ 85 __libelf_seterrno (ELF_E_INVALID_OP); 86 return NULL; 87 } 88 89 if (type >= ELF_T_NUM) 90 { 91 __libelf_seterrno (ELF_E_UNKNOWN_TYPE); 92 return NULL; 93 } 94 95 /* Get the raw bytes from the file. */ 96 void *rawchunk; 97 int flags = 0; 98 Elf_Data *result = NULL; 99 100 rwlock_rdlock (elf->lock); 101 102 /* If the file is mmap'ed we can use it directly. */ 103 if (elf->map_address != NULL) 104 rawchunk = elf->map_address + elf->start_offset + offset; 105 else 106 { 107 /* We allocate the memory and read the data from the file. */ 108 rawchunk = malloc (size); 109 if (rawchunk == NULL) 110 { 111 nomem: 112 __libelf_seterrno (ELF_E_NOMEM); 113 goto out; 114 } 115 116 /* Read the file content. */ 117 if (unlikely ((size_t) pread_retry (elf->fildes, rawchunk, size, 118 elf->start_offset + offset) 119 != size)) 120 { 121 /* Something went wrong. */ 122 free (rawchunk); 123 __libelf_seterrno (ELF_E_READ_ERROR); 124 goto out; 125 } 126 127 flags = ELF_F_MALLOCED; 128 } 129 130 /* Copy and/or convert the data as needed for aligned native-order access. */ 131 size_t align = __libelf_type_align (elf->class, type); 132 void *buffer; 133 if (elf->state.elf32.ehdr->e_ident[EI_DATA] == MY_ELFDATA) 134 { 135 if (((uintptr_t) rawchunk & (align - 1)) == 0) 136 /* No need to copy, we can use the raw data. */ 137 buffer = rawchunk; 138 else 139 { 140 /* A malloc'd block is always sufficiently aligned. */ 141 assert (flags == 0); 142 143 buffer = malloc (size); 144 if (unlikely (buffer == NULL)) 145 goto nomem; 146 flags = ELF_F_MALLOCED; 147 148 /* The copy will be appropriately aligned for direct access. */ 149 memcpy (buffer, rawchunk, size); 150 } 151 } 152 else 153 { 154 if (flags) 155 buffer = rawchunk; 156 else 157 { 158 buffer = malloc (size); 159 if (unlikely (buffer == NULL)) 160 goto nomem; 161 flags = ELF_F_MALLOCED; 162 } 163 164 /* Call the conversion function. */ 165 (*__elf_xfctstom[LIBELF_EV_IDX][LIBELF_EV_IDX][elf->class - 1][type]) 166 (buffer, rawchunk, size, 0); 167 } 168 169 /* Allocate the dummy container to point at this buffer. */ 170 Elf_Data_Chunk *chunk = calloc (1, sizeof *chunk); 171 if (chunk == NULL) 172 { 173 if (flags) 174 free (buffer); 175 goto nomem; 176 } 177 178 chunk->dummy_scn.elf = elf; 179 chunk->dummy_scn.flags = flags; 180 chunk->data.s = &chunk->dummy_scn; 181 chunk->data.d.d_buf = buffer; 182 chunk->data.d.d_size = size; 183 chunk->data.d.d_type = type; 184 chunk->data.d.d_align = align; 185 chunk->data.d.d_version = __libelf_version; 186 187 rwlock_unlock (elf->lock); 188 rwlock_wrlock (elf->lock); 189 190 chunk->next = elf->state.elf.rawchunks; 191 elf->state.elf.rawchunks = chunk; 192 result = &chunk->data.d; 193 194 out: 195 rwlock_unlock (elf->lock); 196 return result; 197 } 198