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 33 #include "_libelf.h" 34 35 ELFTC_VCSID("$Id: gelf_sym.c 2272 2011-12-03 17:07:31Z jkoshy $"); 36 37 GElf_Sym * 38 gelf_getsym(Elf_Data *ed, int ndx, GElf_Sym *dst) 39 { 40 int ec; 41 Elf *e; 42 size_t msz; 43 Elf_Scn *scn; 44 uint32_t sh_type; 45 Elf32_Sym *sym32; 46 Elf64_Sym *sym64; 47 struct _Libelf_Data *d; 48 49 d = (struct _Libelf_Data *) ed; 50 51 if (d == NULL || ndx < 0 || dst == NULL || 52 (scn = d->d_scn) == NULL || 53 (e = scn->s_elf) == NULL) { 54 LIBELF_SET_ERROR(ARGUMENT, 0); 55 return (NULL); 56 } 57 58 ec = e->e_class; 59 assert(ec == ELFCLASS32 || ec == ELFCLASS64); 60 61 if (ec == ELFCLASS32) 62 sh_type = scn->s_shdr.s_shdr32.sh_type; 63 else 64 sh_type = scn->s_shdr.s_shdr64.sh_type; 65 66 if (_libelf_xlate_shtype(sh_type) != ELF_T_SYM) { 67 LIBELF_SET_ERROR(ARGUMENT, 0); 68 return (NULL); 69 } 70 71 msz = _libelf_msize(ELF_T_SYM, ec, e->e_version); 72 73 assert(msz > 0); 74 75 if (msz * ndx >= d->d_data.d_size) { 76 LIBELF_SET_ERROR(ARGUMENT, 0); 77 return (NULL); 78 } 79 80 if (ec == ELFCLASS32) { 81 82 sym32 = (Elf32_Sym *) d->d_data.d_buf + ndx; 83 84 dst->st_name = sym32->st_name; 85 dst->st_value = (Elf64_Addr) sym32->st_value; 86 dst->st_size = (Elf64_Xword) sym32->st_size; 87 dst->st_info = ELF64_ST_INFO(ELF32_ST_BIND(sym32->st_info), 88 ELF32_ST_TYPE(sym32->st_info)); 89 dst->st_other = sym32->st_other; 90 dst->st_shndx = sym32->st_shndx; 91 } else { 92 93 sym64 = (Elf64_Sym *) d->d_data.d_buf + ndx; 94 95 *dst = *sym64; 96 } 97 98 return (dst); 99 } 100 101 int 102 gelf_update_sym(Elf_Data *ed, int ndx, GElf_Sym *gs) 103 { 104 int ec; 105 Elf *e; 106 size_t msz; 107 Elf_Scn *scn; 108 uint32_t sh_type; 109 Elf32_Sym *sym32; 110 Elf64_Sym *sym64; 111 struct _Libelf_Data *d; 112 113 d = (struct _Libelf_Data *) ed; 114 115 if (d == NULL || ndx < 0 || gs == 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_SYM) { 131 LIBELF_SET_ERROR(ARGUMENT, 0); 132 return (0); 133 } 134 135 msz = _libelf_msize(ELF_T_SYM, ec, e->e_version); 136 assert(msz > 0); 137 138 if (msz * ndx >= d->d_data.d_size) { 139 LIBELF_SET_ERROR(ARGUMENT, 0); 140 return (0); 141 } 142 143 if (ec == ELFCLASS32) { 144 sym32 = (Elf32_Sym *) d->d_data.d_buf + ndx; 145 146 sym32->st_name = gs->st_name; 147 sym32->st_info = gs->st_info; 148 sym32->st_other = gs->st_other; 149 sym32->st_shndx = gs->st_shndx; 150 151 LIBELF_COPY_U32(sym32, gs, st_value); 152 LIBELF_COPY_U32(sym32, gs, st_size); 153 } else { 154 sym64 = (Elf64_Sym *) d->d_data.d_buf + ndx; 155 156 *sym64 = *gs; 157 } 158 159 return (1); 160 } 161