Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 1 | /* Return converted data from raw chunk of ELF file. |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame^] | 2 | Copyright (C) 2007, 2014 Red Hat, Inc. |
| 3 | This file is part of elfutils. |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 4 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame^] | 5 | This file is free software; you can redistribute it and/or modify |
| 6 | it under the terms of either |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 7 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame^] | 8 | * the GNU Lesser General Public License as published by the Free |
| 9 | Software Foundation; either version 3 of the License, or (at |
| 10 | your option) any later version |
| 11 | |
| 12 | or |
| 13 | |
| 14 | * the GNU General Public License as published by the Free |
| 15 | Software Foundation; either version 2 of the License, or (at |
| 16 | your option) any later version |
| 17 | |
| 18 | or both in parallel, as here. |
| 19 | |
| 20 | elfutils is distributed in the hope that it will be useful, but |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 21 | WITHOUT ANY WARRANTY; without even the implied warranty of |
| 22 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 23 | General Public License for more details. |
| 24 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame^] | 25 | You should have received copies of the GNU General Public License and |
| 26 | the GNU Lesser General Public License along with this program. If |
| 27 | not, see <http://www.gnu.org/licenses/>. */ |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 28 | |
| 29 | #ifdef HAVE_CONFIG_H |
| 30 | # include <config.h> |
| 31 | #endif |
| 32 | |
| 33 | #include <assert.h> |
| 34 | #include <errno.h> |
| 35 | #include <stdlib.h> |
| 36 | #include <string.h> |
| 37 | #include <unistd.h> |
| 38 | |
| 39 | #include <system.h> |
| 40 | #include "libelfP.h" |
| 41 | #include "common.h" |
| 42 | |
| 43 | Elf_Data * |
| 44 | elf_getdata_rawchunk (elf, offset, size, type) |
| 45 | Elf *elf; |
| 46 | off64_t offset; |
| 47 | size_t size; |
| 48 | Elf_Type type; |
| 49 | { |
| 50 | if (unlikely (elf == NULL)) |
| 51 | return NULL; |
| 52 | |
| 53 | if (unlikely (elf->kind != ELF_K_ELF)) |
| 54 | { |
| 55 | /* No valid descriptor. */ |
| 56 | __libelf_seterrno (ELF_E_INVALID_HANDLE); |
| 57 | return NULL; |
| 58 | } |
| 59 | |
Elliott Hughes | 0333382 | 2015-02-18 22:19:45 -0800 | [diff] [blame^] | 60 | if (unlikely (offset < 0 || (uint64_t) offset > elf->maximum_size |
| 61 | || elf->maximum_size - (uint64_t) offset < size)) |
| 62 | |
Ben Cheng | 25b3c04 | 2013-11-20 14:45:36 -0800 | [diff] [blame] | 63 | { |
| 64 | /* Invalid request. */ |
| 65 | __libelf_seterrno (ELF_E_INVALID_OP); |
| 66 | return NULL; |
| 67 | } |
| 68 | |
| 69 | if (type >= ELF_T_NUM) |
| 70 | { |
| 71 | __libelf_seterrno (ELF_E_UNKNOWN_TYPE); |
| 72 | return NULL; |
| 73 | } |
| 74 | |
| 75 | /* Get the raw bytes from the file. */ |
| 76 | void *rawchunk; |
| 77 | int flags = 0; |
| 78 | Elf_Data *result = NULL; |
| 79 | |
| 80 | rwlock_rdlock (elf->lock); |
| 81 | |
| 82 | /* If the file is mmap'ed we can use it directly. */ |
| 83 | if (elf->map_address != NULL) |
| 84 | rawchunk = elf->map_address + elf->start_offset + offset; |
| 85 | else |
| 86 | { |
| 87 | /* We allocate the memory and read the data from the file. */ |
| 88 | rawchunk = malloc (size); |
| 89 | if (rawchunk == NULL) |
| 90 | { |
| 91 | nomem: |
| 92 | __libelf_seterrno (ELF_E_NOMEM); |
| 93 | goto out; |
| 94 | } |
| 95 | |
| 96 | /* Read the file content. */ |
| 97 | if (unlikely ((size_t) pread_retry (elf->fildes, rawchunk, size, |
| 98 | elf->start_offset + offset) |
| 99 | != size)) |
| 100 | { |
| 101 | /* Something went wrong. */ |
| 102 | free (rawchunk); |
| 103 | __libelf_seterrno (ELF_E_READ_ERROR); |
| 104 | goto out; |
| 105 | } |
| 106 | |
| 107 | flags = ELF_F_MALLOCED; |
| 108 | } |
| 109 | |
| 110 | /* Copy and/or convert the data as needed for aligned native-order access. */ |
| 111 | size_t align = __libelf_type_align (elf->class, type); |
| 112 | void *buffer; |
| 113 | if (elf->state.elf32.ehdr->e_ident[EI_DATA] == MY_ELFDATA) |
| 114 | { |
| 115 | if (((uintptr_t) rawchunk & (align - 1)) == 0) |
| 116 | /* No need to copy, we can use the raw data. */ |
| 117 | buffer = rawchunk; |
| 118 | else |
| 119 | { |
| 120 | /* A malloc'd block is always sufficiently aligned. */ |
| 121 | assert (flags == 0); |
| 122 | |
| 123 | buffer = malloc (size); |
| 124 | if (unlikely (buffer == NULL)) |
| 125 | goto nomem; |
| 126 | flags = ELF_F_MALLOCED; |
| 127 | |
| 128 | /* The copy will be appropriately aligned for direct access. */ |
| 129 | memcpy (buffer, rawchunk, size); |
| 130 | } |
| 131 | } |
| 132 | else |
| 133 | { |
| 134 | if (flags) |
| 135 | buffer = rawchunk; |
| 136 | else |
| 137 | { |
| 138 | buffer = malloc (size); |
| 139 | if (unlikely (buffer == NULL)) |
| 140 | goto nomem; |
| 141 | flags = ELF_F_MALLOCED; |
| 142 | } |
| 143 | |
| 144 | /* Call the conversion function. */ |
| 145 | (*__elf_xfctstom[LIBELF_EV_IDX][LIBELF_EV_IDX][elf->class - 1][type]) |
| 146 | (buffer, rawchunk, size, 0); |
| 147 | } |
| 148 | |
| 149 | /* Allocate the dummy container to point at this buffer. */ |
| 150 | Elf_Data_Chunk *chunk = calloc (1, sizeof *chunk); |
| 151 | if (chunk == NULL) |
| 152 | { |
| 153 | if (flags) |
| 154 | free (buffer); |
| 155 | goto nomem; |
| 156 | } |
| 157 | |
| 158 | chunk->dummy_scn.elf = elf; |
| 159 | chunk->dummy_scn.flags = flags; |
| 160 | chunk->data.s = &chunk->dummy_scn; |
| 161 | chunk->data.d.d_buf = buffer; |
| 162 | chunk->data.d.d_size = size; |
| 163 | chunk->data.d.d_type = type; |
| 164 | chunk->data.d.d_align = align; |
| 165 | chunk->data.d.d_version = __libelf_version; |
| 166 | |
| 167 | rwlock_unlock (elf->lock); |
| 168 | rwlock_wrlock (elf->lock); |
| 169 | |
| 170 | chunk->next = elf->state.elf.rawchunks; |
| 171 | elf->state.elf.rawchunks = chunk; |
| 172 | result = &chunk->data.d; |
| 173 | |
| 174 | out: |
| 175 | rwlock_unlock (elf->lock); |
| 176 | return result; |
| 177 | } |