1 /*- 2 * Copyright (c) 2006,2008 Joseph Koshy 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24 * SUCH DAMAGE. 25 */ 26 27 #include <sys/cdefs.h> 28 29 #include <assert.h> 30 #include <gelf.h> 31 #include <limits.h> 32 #include <stdint.h> 33 34 #include "_libelf.h" 35 36 ELFTC_VCSID("$Id: gelf_dyn.c 2998 2014-03-18 17:19:00Z jkoshy $"); 37 38 GElf_Dyn * 39 gelf_getdyn(Elf_Data *ed, int ndx, GElf_Dyn *dst) 40 { 41 int ec; 42 Elf *e; 43 size_t msz; 44 Elf_Scn *scn; 45 Elf32_Dyn *dyn32; 46 Elf64_Dyn *dyn64; 47 uint32_t sh_type; 48 struct _Libelf_Data *d; 49 50 d = (struct _Libelf_Data *) ed; 51 52 if (d == NULL || ndx < 0 || dst == NULL || 53 (scn = d->d_scn) == NULL || 54 (e = scn->s_elf) == NULL) { 55 LIBELF_SET_ERROR(ARGUMENT, 0); 56 return (NULL); 57 } 58 59 ec = e->e_class; 60 assert(ec == ELFCLASS32 || ec == ELFCLASS64); 61 62 if (ec == ELFCLASS32) 63 sh_type = scn->s_shdr.s_shdr32.sh_type; 64 else 65 sh_type = scn->s_shdr.s_shdr64.sh_type; 66 67 if (_libelf_xlate_shtype(sh_type) != ELF_T_DYN) { 68 LIBELF_SET_ERROR(ARGUMENT, 0); 69 return (NULL); 70 } 71 72 msz = _libelf_msize(ELF_T_DYN, ec, e->e_version); 73 74 assert(msz > 0); 75 assert(ndx >= 0); 76 77 if (msz * (size_t) ndx >= d->d_data.d_size) { 78 LIBELF_SET_ERROR(ARGUMENT, 0); 79 return (NULL); 80 } 81 82 if (ec == ELFCLASS32) { 83 dyn32 = (Elf32_Dyn *) d->d_data.d_buf + ndx; 84 85 dst->d_tag = dyn32->d_tag; 86 dst->d_un.d_val = (Elf64_Xword) dyn32->d_un.d_val; 87 88 } else { 89 90 dyn64 = (Elf64_Dyn *) d->d_data.d_buf + ndx; 91 92 *dst = *dyn64; 93 } 94 95 return (dst); 96 } 97 98 int 99 gelf_update_dyn(Elf_Data *ed, int ndx, GElf_Dyn *ds) 100 { 101 int ec; 102 Elf *e; 103 size_t msz; 104 Elf_Scn *scn; 105 Elf32_Dyn *dyn32; 106 Elf64_Dyn *dyn64; 107 uint32_t sh_type; 108 struct _Libelf_Data *d; 109 110 d = (struct _Libelf_Data *) ed; 111 112 if (d == NULL || ndx < 0 || ds == NULL || 113 (scn = d->d_scn) == NULL || 114 (e = scn->s_elf) == NULL) { 115 LIBELF_SET_ERROR(ARGUMENT, 0); 116 return (0); 117 } 118 119 ec = e->e_class; 120 assert(ec == ELFCLASS32 || ec == ELFCLASS64); 121 122 if (ec == ELFCLASS32) 123 sh_type = scn->s_shdr.s_shdr32.sh_type; 124 else 125 sh_type = scn->s_shdr.s_shdr64.sh_type; 126 127 if (_libelf_xlate_shtype(sh_type) != ELF_T_DYN) { 128 LIBELF_SET_ERROR(ARGUMENT, 0); 129 return (0); 130 } 131 132 msz = _libelf_msize(ELF_T_DYN, ec, e->e_version); 133 134 assert(msz > 0); 135 assert(ndx >= 0); 136 137 if (msz * (size_t) ndx >= d->d_data.d_size) { 138 LIBELF_SET_ERROR(ARGUMENT, 0); 139 return (0); 140 } 141 142 if (ec == ELFCLASS32) { 143 dyn32 = (Elf32_Dyn *) d->d_data.d_buf + ndx; 144 145 LIBELF_COPY_S32(dyn32, ds, d_tag); 146 LIBELF_COPY_U32(dyn32, ds, d_un.d_val); 147 } else { 148 dyn64 = (Elf64_Dyn *) d->d_data.d_buf + ndx; 149 150 *dyn64 = *ds; 151 } 152 153 return (1); 154 } 155