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 3739 2019-05-06 05:18:15Z jkoshy $"); 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 if ((msz = _libelf_msize(ELF_T_RELA, ec, e->e_version)) == 0) 71 return (NULL); 72 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 if (_libelf_is_mips64el(e)) 96 dst->r_info = 97 _libelf_mips64el_r_info_tom(rela64->r_info); 98 } 99 100 return (dst); 101 } 102 103 int 104 gelf_update_rela(Elf_Data *ed, int ndx, GElf_Rela *dr) 105 { 106 int ec; 107 Elf *e; 108 size_t msz; 109 Elf_Scn *scn; 110 uint32_t sh_type; 111 Elf32_Rela *rela32; 112 Elf64_Rela *rela64; 113 struct _Libelf_Data *d; 114 115 d = (struct _Libelf_Data *) ed; 116 117 if (d == NULL || ndx < 0 || dr == NULL || 118 (scn = d->d_scn) == NULL || 119 (e = scn->s_elf) == NULL) { 120 LIBELF_SET_ERROR(ARGUMENT, 0); 121 return (0); 122 } 123 124 ec = e->e_class; 125 assert(ec == ELFCLASS32 || ec == ELFCLASS64); 126 127 if (ec == ELFCLASS32) 128 sh_type = scn->s_shdr.s_shdr32.sh_type; 129 else 130 sh_type = scn->s_shdr.s_shdr64.sh_type; 131 132 if (_libelf_xlate_shtype(sh_type) != ELF_T_RELA) { 133 LIBELF_SET_ERROR(ARGUMENT, 0); 134 return (0); 135 } 136 137 if ((msz = _libelf_msize(ELF_T_RELA, ec, e->e_version)) == 0) 138 return (0); 139 140 assert(ndx >= 0); 141 142 if (msz * (size_t) ndx >= d->d_data.d_size) { 143 LIBELF_SET_ERROR(ARGUMENT, 0); 144 return (0); 145 } 146 147 if (ec == ELFCLASS32) { 148 rela32 = (Elf32_Rela *) d->d_data.d_buf + ndx; 149 150 LIBELF_COPY_U32(rela32, dr, r_offset); 151 152 if (ELF64_R_SYM(dr->r_info) > ELF32_R_SYM(~0U) || 153 ELF64_R_TYPE(dr->r_info) > ELF32_R_TYPE(~0U)) { 154 LIBELF_SET_ERROR(RANGE, 0); 155 return (0); 156 } 157 rela32->r_info = ELF32_R_INFO( 158 (Elf32_Word) ELF64_R_SYM(dr->r_info), 159 (Elf32_Word) ELF64_R_TYPE(dr->r_info)); 160 161 LIBELF_COPY_S32(rela32, dr, r_addend); 162 } else { 163 rela64 = (Elf64_Rela *) d->d_data.d_buf + ndx; 164 165 *rela64 = *dr; 166 167 if (_libelf_is_mips64el(e)) 168 rela64->r_info = _libelf_mips64el_r_info_tof(dr->r_info); 169 } 170 171 return (1); 172 } 173