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_rela.c 2998 2014-03-18 17:19:00Z jkoshy $"); 37 38 GElf_Rela * 39 gelf_getrela(Elf_Data *ed, int ndx, GElf_Rela *dst) 40 { 41 int ec; 42 Elf *e; 43 size_t msz; 44 Elf_Scn *scn; 45 uint32_t sh_type; 46 Elf32_Rela *rela32; 47 Elf64_Rela *rela64; 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_RELA) { 68 LIBELF_SET_ERROR(ARGUMENT, 0); 69 return (NULL); 70 } 71 72 msz = _libelf_msize(ELF_T_RELA, 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 rela32 = (Elf32_Rela *) d->d_data.d_buf + ndx; 84 85 dst->r_offset = (Elf64_Addr) rela32->r_offset; 86 dst->r_info = ELF64_R_INFO( 87 (Elf64_Xword) ELF32_R_SYM(rela32->r_info), 88 ELF32_R_TYPE(rela32->r_info)); 89 dst->r_addend = (Elf64_Sxword) rela32->r_addend; 90 91 } else { 92 93 rela64 = (Elf64_Rela *) d->d_data.d_buf + ndx; 94 95 *dst = *rela64; 96 } 97 98 return (dst); 99 } 100 101 int 102 gelf_update_rela(Elf_Data *ed, int ndx, GElf_Rela *dr) 103 { 104 int ec; 105 Elf *e; 106 size_t msz; 107 Elf_Scn *scn; 108 uint32_t sh_type; 109 Elf32_Rela *rela32; 110 Elf64_Rela *rela64; 111 struct _Libelf_Data *d; 112 113 d = (struct _Libelf_Data *) ed; 114 115 if (d == NULL || ndx < 0 || dr == NULL || 116 (scn = d->d_scn) == NULL || 117 (e = scn->s_elf) == NULL) { 118 LIBELF_SET_ERROR(ARGUMENT, 0); 119 return (0); 120 } 121 122 ec = e->e_class; 123 assert(ec == ELFCLASS32 || ec == ELFCLASS64); 124 125 if (ec == ELFCLASS32) 126 sh_type = scn->s_shdr.s_shdr32.sh_type; 127 else 128 sh_type = scn->s_shdr.s_shdr64.sh_type; 129 130 if (_libelf_xlate_shtype(sh_type) != ELF_T_RELA) { 131 LIBELF_SET_ERROR(ARGUMENT, 0); 132 return (0); 133 } 134 135 msz = _libelf_msize(ELF_T_RELA, ec, e->e_version); 136 137 assert(msz > 0); 138 assert(ndx >= 0); 139 140 if (msz * (size_t) ndx >= d->d_data.d_size) { 141 LIBELF_SET_ERROR(ARGUMENT, 0); 142 return (0); 143 } 144 145 if (ec == ELFCLASS32) { 146 rela32 = (Elf32_Rela *) d->d_data.d_buf + ndx; 147 148 LIBELF_COPY_U32(rela32, dr, r_offset); 149 150 if (ELF64_R_SYM(dr->r_info) > ELF32_R_SYM(~0UL) || 151 ELF64_R_TYPE(dr->r_info) > ELF32_R_TYPE(~0U)) { 152 LIBELF_SET_ERROR(RANGE, 0); 153 return (0); 154 } 155 rela32->r_info = ELF32_R_INFO( 156 (Elf32_Word) ELF64_R_SYM(dr->r_info), 157 (Elf32_Word) ELF64_R_TYPE(dr->r_info)); 158 159 LIBELF_COPY_S32(rela32, dr, r_addend); 160 } else { 161 rela64 = (Elf64_Rela *) d->d_data.d_buf + ndx; 162 163 *rela64 = *dr; 164 } 165 166 return (1); 167 } 168