1 /* Return symbol table of archive. 2 Copyright (C) 1998, 1999, 2000, 2002, 2005 Red Hat, Inc. 3 This file is part of Red Hat elfutils. 4 Written by Ulrich Drepper <drepper (at) redhat.com>, 1998. 5 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. 9 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. 14 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>. */ 50 51 #ifdef HAVE_CONFIG_H 52 # include <config.h> 53 #endif 54 55 #include <assert.h> 56 #include <byteswap.h> 57 #include <endian.h> 58 #include <errno.h> 59 #include <stdint.h> 60 #include <stdlib.h> 61 #include <string.h> 62 #include <unistd.h> 63 64 #include <system.h> 65 #include <dl-hash.h> 66 #include "libelfP.h" 67 68 69 Elf_Arsym * 70 elf_getarsym (elf, ptr) 71 Elf *elf; 72 size_t *ptr; 73 { 74 if (elf->kind != ELF_K_AR) 75 { 76 /* This is no archive. */ 77 __libelf_seterrno (ELF_E_NO_ARCHIVE); 78 return NULL; 79 } 80 81 if (ptr != NULL) 82 /* In case of an error or when we know the value store the expected 83 value now. Doing this allows us easier exits in an error case. */ 84 *ptr = elf->state.ar.ar_sym_num; 85 86 if (elf->state.ar.ar_sym == (Elf_Arsym *) -1l) 87 { 88 /* There is no index. */ 89 __libelf_seterrno (ELF_E_NO_INDEX); 90 return NULL; 91 } 92 93 Elf_Arsym *result = elf->state.ar.ar_sym; 94 if (result == NULL) 95 { 96 /* We have not yet read the index. */ 97 rwlock_wrlock (elf->lock); 98 99 /* In case we find no index remember this for the next call. */ 100 elf->state.ar.ar_sym = (Elf_Arsym *) -1l; 101 102 struct ar_hdr *index_hdr; 103 if (elf->map_address == NULL) 104 { 105 /* We must read index from the file. */ 106 assert (elf->fildes != -1); 107 if (pread_retry (elf->fildes, &elf->state.ar.ar_hdr, 108 sizeof (struct ar_hdr), elf->start_offset + SARMAG) 109 != sizeof (struct ar_hdr)) 110 { 111 /* It is not possible to read the index. Maybe it does not 112 exist. */ 113 __libelf_seterrno (ELF_E_READ_ERROR); 114 goto out; 115 } 116 117 index_hdr = &elf->state.ar.ar_hdr; 118 } 119 else 120 { 121 if (SARMAG + sizeof (struct ar_hdr) > elf->maximum_size) 122 { 123 /* There is no room for the full archive. */ 124 __libelf_seterrno (ELF_E_NO_INDEX); 125 goto out; 126 } 127 128 index_hdr = (struct ar_hdr *) (elf->map_address 129 + elf->start_offset + SARMAG); 130 } 131 132 /* Now test whether this really is an archive. */ 133 if (memcmp (index_hdr->ar_fmag, ARFMAG, 2) != 0) 134 { 135 /* Invalid magic bytes. */ 136 __libelf_seterrno (ELF_E_ARCHIVE_FMAG); 137 goto out; 138 } 139 140 /* Now test whether this is the index. It is denoted by the 141 name being "/ ". 142 XXX This is not entirely true. There are some more forms. 143 Which of them shall we handle? */ 144 if (memcmp (index_hdr->ar_name, "/ ", 16) != 0) 145 { 146 /* If the index is not the first entry, there is no index. 147 148 XXX Is this true? */ 149 __libelf_seterrno (ELF_E_NO_INDEX); 150 goto out; 151 } 152 153 /* We have an archive. The first word in there is the number of 154 entries in the table. */ 155 uint32_t n; 156 if (elf->map_address == NULL) 157 { 158 if (pread_retry (elf->fildes, &n, sizeof (n), 159 elf->start_offset + SARMAG + sizeof (struct ar_hdr)) 160 != sizeof (n)) 161 { 162 /* Cannot read the number of entries. */ 163 __libelf_seterrno (ELF_E_NO_INDEX); 164 goto out; 165 } 166 } 167 else 168 n = *(uint32_t *) (elf->map_address + elf->start_offset 169 + SARMAG + sizeof (struct ar_hdr)); 170 171 if (__BYTE_ORDER == __LITTLE_ENDIAN) 172 n = bswap_32 (n); 173 174 /* Now we can perform some first tests on whether all the data 175 needed for the index is available. */ 176 char tmpbuf[17]; 177 memcpy (tmpbuf, index_hdr->ar_size, 10); 178 tmpbuf[10] = '\0'; 179 size_t index_size = atol (tmpbuf); 180 181 if (SARMAG + sizeof (struct ar_hdr) + index_size > elf->maximum_size 182 || n * sizeof (uint32_t) > index_size) 183 { 184 /* This index table cannot be right since it does not fit into 185 the file. */ 186 __libelf_seterrno (ELF_E_NO_INDEX); 187 goto out; 188 } 189 190 /* Now we can allocate the arrays needed to store the index. */ 191 size_t ar_sym_len = (n + 1) * sizeof (Elf_Arsym); 192 elf->state.ar.ar_sym = (Elf_Arsym *) malloc (ar_sym_len); 193 if (elf->state.ar.ar_sym != NULL) 194 { 195 uint32_t *file_data; 196 char *str_data; 197 198 if (elf->map_address == NULL) 199 { 200 file_data = (uint32_t *) alloca (n * sizeof (uint32_t)); 201 202 ar_sym_len += index_size - n * sizeof (uint32_t); 203 Elf_Arsym *newp = (Elf_Arsym *) realloc (elf->state.ar.ar_sym, 204 ar_sym_len); 205 if (newp == NULL) 206 { 207 free (elf->state.ar.ar_sym); 208 elf->state.ar.ar_sym = NULL; 209 __libelf_seterrno (ELF_E_NOMEM); 210 goto out; 211 } 212 elf->state.ar.ar_sym = newp; 213 214 char *new_str = (char *) (elf->state.ar.ar_sym + n + 1); 215 216 /* Now read the data from the file. */ 217 if ((size_t) pread_retry (elf->fildes, file_data, 218 n * sizeof (uint32_t), 219 elf->start_offset + SARMAG 220 + sizeof (struct ar_hdr) 221 + sizeof (uint32_t)) 222 != n * sizeof (uint32_t) 223 || ((size_t) pread_retry (elf->fildes, new_str, 224 index_size - n * sizeof (uint32_t), 225 elf->start_offset 226 + SARMAG + sizeof (struct ar_hdr) 227 + (n + 1) * sizeof (uint32_t)) 228 != index_size - n * sizeof (uint32_t))) 229 { 230 /* We were not able to read the data. */ 231 free (elf->state.ar.ar_sym); 232 elf->state.ar.ar_sym = NULL; 233 __libelf_seterrno (ELF_E_NO_INDEX); 234 goto out; 235 } 236 237 str_data = (char *) new_str; 238 } 239 else 240 { 241 file_data = (uint32_t *) (elf->map_address + elf->start_offset 242 + SARMAG + sizeof (struct ar_hdr) 243 + sizeof (uint32_t)); 244 str_data = (char *) &file_data[n]; 245 } 246 247 /* Now we can build the data structure. */ 248 Elf_Arsym *arsym = elf->state.ar.ar_sym; 249 for (size_t cnt = 0; cnt < n; ++cnt) 250 { 251 arsym[cnt].as_name = str_data; 252 if (__BYTE_ORDER == __LITTLE_ENDIAN) 253 arsym[cnt].as_off = bswap_32 (file_data[cnt]); 254 else 255 arsym[cnt].as_off = file_data[cnt]; 256 arsym[cnt].as_hash = _dl_elf_hash (str_data); 257 str_data = rawmemchr (str_data, '\0') + 1; 258 } 259 /* At the end a special entry. */ 260 arsym[n].as_name = NULL; 261 arsym[n].as_off = 0; 262 arsym[n].as_hash = ~0UL; 263 264 /* Tell the caller how many entries we have. */ 265 elf->state.ar.ar_sym_num = n + 1; 266 } 267 268 result = elf->state.ar.ar_sym; 269 270 out: 271 rwlock_unlock (elf->lock); 272 } 273 274 if (ptr != NULL) 275 *ptr = elf->state.ar.ar_sym_num; 276 277 return result; 278 } 279
