mdreloc.c revision 1.15
1 /* $NetBSD: mdreloc.c,v 1.15 2002/09/06 15:17:59 mycroft Exp $ */ 2 3 /* 4 * Copyright (c) 2001 Wasabi Systems, Inc. 5 * All rights reserved. 6 * 7 * Written by Frank van der Linden for Wasabi Systems, Inc. 8 * 9 * Redistribution and use in source and binary forms, with or without 10 * modification, are permitted provided that the following conditions 11 * are met: 12 * 1. Redistributions of source code must retain the above copyright 13 * notice, this list of conditions and the following disclaimer. 14 * 2. Redistributions in binary form must reproduce the above copyright 15 * notice, this list of conditions and the following disclaimer in the 16 * documentation and/or other materials provided with the distribution. 17 * 3. All advertising materials mentioning features or use of this software 18 * must display the following acknowledgement: 19 * This product includes software developed for the NetBSD Project by 20 * Wasabi Systems, Inc. 21 * 4. The name of Wasabi Systems, Inc. may not be used to endorse 22 * or promote products derived from this software without specific prior 23 * written permission. 24 * 25 * THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``AS IS'' AND 26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 27 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 28 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL WASABI SYSTEMS, INC 29 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 30 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 31 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 32 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 33 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 34 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 35 * POSSIBILITY OF SUCH DAMAGE. 36 */ 37 38 /* 39 * Copyright 1996 John D. Polstra. 40 * Copyright 1996 Matt Thomas <matt (at) 3am-software.com> 41 * All rights reserved. 42 * 43 * Redistribution and use in source and binary forms, with or without 44 * modification, are permitted provided that the following conditions 45 * are met: 46 * 1. Redistributions of source code must retain the above copyright 47 * notice, this list of conditions and the following disclaimer. 48 * 2. Redistributions in binary form must reproduce the above copyright 49 * notice, this list of conditions and the following disclaimer in the 50 * documentation and/or other materials provided with the distribution. 51 * 3. All advertising materials mentioning features or use of this software 52 * must display the following acknowledgement: 53 * This product includes software developed by John Polstra. 54 * 4. The name of the author may not be used to endorse or promote products 55 * derived from this software without specific prior written permission. 56 * 57 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 58 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 59 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 60 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 61 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 62 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 63 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 64 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 65 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 66 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 67 */ 68 69 #include <sys/types.h> 70 #include <sys/mman.h> 71 #include <err.h> 72 #include <errno.h> 73 #include <fcntl.h> 74 #include <stdarg.h> 75 #include <stdio.h> 76 #include <stdlib.h> 77 #include <string.h> 78 #include <unistd.h> 79 #include <elf.h> 80 81 #include "debug.h" 82 #include "rtld.h" 83 84 void 85 _rtld_setup_pltgot(const Obj_Entry *obj) 86 { 87 obj->pltgot[1] = (Elf_Addr) obj; 88 obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start; 89 } 90 91 int 92 _rtld_relocate_nonplt_objects(obj, self, dodebug) 93 const Obj_Entry *obj; 94 bool self; 95 bool dodebug; 96 { 97 const Elf_Rela *rela; 98 99 for (rela = obj->rela; rela < obj->relalim; rela++) { 100 Elf64_Addr *where64; 101 Elf32_Addr *where32; 102 const Elf_Sym *def; 103 const Obj_Entry *defobj; 104 Elf64_Addr tmp64; 105 Elf32_Addr tmp32; 106 unsigned long symnum; 107 108 where64 = (Elf64_Addr *)(obj->relocbase + rela->r_offset); 109 where32 = (Elf32_Addr *)where64; 110 symnum = ELF_R_SYM(rela->r_info); 111 112 switch (ELF_R_TYPE(rela->r_info)) { 113 case R_TYPE(NONE): 114 break; 115 116 case R_TYPE(32): /* word32 S + A, truncate */ 117 case R_TYPE(32S): /* word32 S + A, signed truncate */ 118 case R_TYPE(GOT32): /* word32 G + A (XXX can we see these?) */ 119 def = _rtld_find_symdef(symnum, obj, &defobj, false); 120 if (def == NULL) 121 return -1; 122 tmp32 = (Elf32_Addr)(u_long)(defobj->relocbase + 123 def->st_value + rela->r_addend); 124 125 if (*where32 != tmp32) 126 *where32 = tmp32; 127 rdbg(dodebug, ("32/32S %s in %s --> %p in %s", 128 obj->strtab + obj->symtab[symnum].st_name, 129 obj->path, (void *)(unsigned long)*where32, 130 defobj->path)); 131 break; 132 case R_TYPE(64): /* word64 S + A */ 133 def = _rtld_find_symdef(symnum, obj, &defobj, false); 134 if (def == NULL) 135 return -1; 136 137 tmp64 = (Elf64_Addr)(defobj->relocbase + def->st_value + 138 rela->r_addend); 139 140 if (*where64 != tmp64) 141 *where64 = tmp64; 142 rdbg(dodebug, ("64 %s in %s --> %p in %s", 143 obj->strtab + obj->symtab[symnum].st_name, 144 obj->path, (void *)*where64, defobj->path)); 145 break; 146 case R_TYPE(PC32): /* word32 S + A - P */ 147 def = _rtld_find_symdef(symnum, obj, &defobj, false); 148 if (def == NULL) 149 return -1; 150 tmp32 = (Elf32_Addr)(u_long)(defobj->relocbase + 151 def->st_value + rela->r_addend - 152 (Elf64_Addr)where64); 153 if (*where32 != tmp32) 154 *where32 = tmp32; 155 rdbg(dodebug, ("PC32 %s in %s --> %p in %s", 156 obj->strtab + obj->symtab[symnum].st_name, 157 obj->path, (void *)(unsigned long)*where32, 158 defobj->path)); 159 break; 160 case R_TYPE(GLOB_DAT): /* word64 S */ 161 def = _rtld_find_symdef(symnum, obj, &defobj, false); 162 if (def == NULL) 163 return -1; 164 165 tmp64 = (Elf64_Addr)(defobj->relocbase + def->st_value); 166 167 if (*where64 != tmp64) 168 *where64 = tmp64; 169 rdbg(dodebug, ("64 %s in %s --> %p in %s", 170 obj->strtab + obj->symtab[symnum].st_name, 171 obj->path, (void *)*where64, defobj->path)); 172 break; 173 case R_TYPE(RELATIVE): /* word64 B + A */ 174 tmp64 = (Elf64_Addr)(obj->relocbase + rela->r_addend); 175 if (*where64 != tmp64) 176 *where64 = tmp64; 177 rdbg(dodebug, ("RELATIVE in %s --> %p", obj->path, 178 (void *)*where64)); 179 break; 180 181 case R_TYPE(COPY): 182 rdbg(dodebug, ("COPY")); 183 break; 184 185 default: 186 rdbg(dodebug, ("sym = %lu, type = %lu, offset = %p, " 187 "addend = %p, contents = %p, symbol = %s", 188 symnum, (u_long)ELF_R_TYPE(rela->r_info), 189 (void *)rela->r_offset, (void *)rela->r_addend, 190 (void *)*where64, 191 obj->strtab + obj->symtab[symnum].st_name)); 192 _rtld_error("%s: Unsupported relocation type %ld " 193 "in non-PLT relocations\n", 194 obj->path, (u_long) ELF_R_TYPE(rela->r_info)); 195 return -1; 196 } 197 } 198 return 0; 199 } 200 201 int 202 _rtld_relocate_plt_lazy(obj, dodebug) 203 const Obj_Entry *obj; 204 bool dodebug; 205 { 206 const Elf_Rela *rela; 207 208 if (!obj->isdynamic) 209 return 0; 210 211 for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) { 212 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset); 213 214 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JUMP_SLOT)); 215 216 /* Just relocate the GOT slots pointing into the PLT */ 217 *where += (Elf_Addr)obj->relocbase; 218 rdbg(dodebug, ("fixup !main in %s --> %p", obj->path, 219 (void *)*where)); 220 } 221 222 return 0; 223 } 224 225 int 226 _rtld_relocate_plt_object(obj, rela, addrp, dodebug) 227 const Obj_Entry *obj; 228 const Elf_Rela *rela; 229 caddr_t *addrp; 230 bool dodebug; 231 { 232 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset); 233 Elf_Addr new_value; 234 const Elf_Sym *def; 235 const Obj_Entry *defobj; 236 237 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JUMP_SLOT)); 238 239 def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true); 240 if (def == NULL) 241 return -1; 242 243 new_value = (Elf_Addr)(defobj->relocbase + def->st_value + 244 rela->r_addend); 245 rdbg(dodebug, ("bind now/fixup in %s --> old=%p new=%p", 246 defobj->strtab + def->st_name, (void *)*where, (void *)new_value)); 247 if (*where != new_value) 248 *where = new_value; 249 250 *addrp = (caddr_t)(new_value - rela->r_addend); 251 return 0; 252 } 253
Indexes created Fri Oct 03 02:09:57 GMT 2025