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 <assert.h> 28 #include <gelf.h> 29 #include <limits.h> 30 #include <stdint.h> 31 32 #include "_libelf.h" 33 34 ELFTC_VCSID("$Id: gelf_rela.c 3177 2015-03-30 18:19:41Z emaste $"); 35 36 GElf_Rela * 37 gelf_getrela(Elf_Data *ed, int ndx, GElf_Rela *dst) 38 { 39 int ec; 40 Elf *e; 41 size_t msz; 42 Elf_Scn *scn; 43 uint32_t sh_type; 44 Elf32_Rela *rela32; 45 Elf64_Rela *rela64; 46 struct _Libelf_Data *d; 47 48 d = (struct _Libelf_Data *) ed; 49 50 if (d == NULL || ndx < 0 || dst == NULL || 51 (scn = d->d_scn) == NULL || 52 (e = scn->s_elf) == NULL) { 53 LIBELF_SET_ERROR(ARGUMENT, 0); 54 return (NULL); 55 } 56 57 ec = e->e_class; 58 assert(ec == ELFCLASS32 || ec == ELFCLASS64); 59 60 if (ec == ELFCLASS32) 61 sh_type = scn->s_shdr.s_shdr32.sh_type; 62 else 63 sh_type = scn->s_shdr.s_shdr64.sh_type; 64 65 if (_libelf_xlate_shtype(sh_type) != ELF_T_RELA) { 66 LIBELF_SET_ERROR(ARGUMENT, 0); 67 return (NULL); 68 } 69 70 msz = _libelf_msize(ELF_T_RELA, ec, e->e_version); 71 72 assert(msz > 0); 73 assert(ndx >= 0); 74 75 if (msz * (size_t) ndx >= d->d_data.d_size) { 76 LIBELF_SET_ERROR(ARGUMENT, 0); 77 return (NULL); 78 } 79 80 if (ec == ELFCLASS32) { 81 rela32 = (Elf32_Rela *) d->d_data.d_buf + ndx; 82 83 dst->r_offset = (Elf64_Addr) rela32->r_offset; 84 dst->r_info = ELF64_R_INFO( 85 (Elf64_Xword) ELF32_R_SYM(rela32->r_info), 86 ELF32_R_TYPE(rela32->r_info)); 87 dst->r_addend = (Elf64_Sxword) rela32->r_addend; 88 89 } else { 90 91 rela64 = (Elf64_Rela *) d->d_data.d_buf + ndx; 92 93 *dst = *rela64; 94 } 95 96 return (dst); 97 } 98 99 int 100 gelf_update_rela(Elf_Data *ed, int ndx, GElf_Rela *dr) 101 { 102 int ec; 103 Elf *e; 104 size_t msz; 105 Elf_Scn *scn; 106 uint32_t sh_type; 107 Elf32_Rela *rela32; 108 Elf64_Rela *rela64; 109 struct _Libelf_Data *d; 110 111 d = (struct _Libelf_Data *) ed; 112 113 if (d == NULL || ndx < 0 || dr == NULL || 114 (scn = d->d_scn) == NULL || 115 (e = scn->s_elf) == NULL) { 116 LIBELF_SET_ERROR(ARGUMENT, 0); 117 return (0); 118 } 119 120 ec = e->e_class; 121 assert(ec == ELFCLASS32 || ec == ELFCLASS64); 122 123 if (ec == ELFCLASS32) 124 sh_type = scn->s_shdr.s_shdr32.sh_type; 125 else 126 sh_type = scn->s_shdr.s_shdr64.sh_type; 127 128 if (_libelf_xlate_shtype(sh_type) != ELF_T_RELA) { 129 LIBELF_SET_ERROR(ARGUMENT, 0); 130 return (0); 131 } 132 133 msz = _libelf_msize(ELF_T_RELA, ec, e->e_version); 134 135 assert(msz > 0); 136 assert(ndx >= 0); 137 138 if (msz * (size_t) ndx >= d->d_data.d_size) { 139 LIBELF_SET_ERROR(ARGUMENT, 0); 140 return (0); 141 } 142 143 if (ec == ELFCLASS32) { 144 rela32 = (Elf32_Rela *) d->d_data.d_buf + ndx; 145 146 LIBELF_COPY_U32(rela32, dr, r_offset); 147 148 if (ELF64_R_SYM(dr->r_info) > ELF32_R_SYM(~0UL) || 149 ELF64_R_TYPE(dr->r_info) > ELF32_R_TYPE(~0U)) { 150 LIBELF_SET_ERROR(RANGE, 0); 151 return (0); 152 } 153 rela32->r_info = ELF32_R_INFO( 154 (Elf32_Word) ELF64_R_SYM(dr->r_info), 155 (Elf32_Word) ELF64_R_TYPE(dr->r_info)); 156 157 LIBELF_COPY_S32(rela32, dr, r_addend); 158 } else { 159 rela64 = (Elf64_Rela *) d->d_data.d_buf + ndx; 160 161 *rela64 = *dr; 162 } 163 164 return (1); 165 } 166