mips_reloc.c revision 1.26
1 /* $NetBSD: mips_reloc.c,v 1.26 2002/09/13 16:03:20 mycroft Exp $ */ 2 3 /* 4 * Copyright 1997 Michael L. Hitch <mhitch (at) montana.edu> 5 * Portions copyright 2002 Charles M. Hannum. 6 * All rights reserved. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 1. Redistributions of source code must retain the above copyright 12 * notice, this list of conditions and the following disclaimer. 13 * 2. Redistributions in binary form must reproduce the above copyright 14 * notice, this list of conditions and the following disclaimer in the 15 * documentation and/or other materials provided with the distribution. 16 * 3. The name of the author may not be used to endorse or promote products 17 * derived from this software without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 20 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 21 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 22 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 23 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 24 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 28 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 32 #include <stdarg.h> 33 #include <sys/types.h> 34 #include <sys/stat.h> 35 36 #include "debug.h" 37 #include "rtld.h" 38 39 void _rtld_bind_start(void); 40 void _rtld_relocate_nonplt_self(Elf_Dyn *, Elf_Addr); 41 caddr_t _rtld_bind_mips(Elf_Word, Elf_Addr, Elf_Addr, Elf_Addr); 42 43 caddr_t 44 _rtld_bind_mips(a0, a1, a2, a3) 45 Elf_Word a0; 46 Elf_Addr a1, a2, a3; 47 { 48 Elf_Addr *u = (Elf_Addr *)(a2 - 0x7ff0); 49 const Obj_Entry *obj = (Obj_Entry *)(u[1] & 0x7fffffff); 50 const Elf_Sym *def; 51 const Obj_Entry *defobj; 52 Elf_Addr new_value; 53 54 def = _rtld_find_symdef(a0, obj, &defobj, true); 55 if (def == NULL) 56 return(NULL); /* XXX */ 57 58 new_value = (Elf_Addr)(defobj->relocbase + def->st_value); 59 rdbg(("bind now/fixup in %s --> new=%p", 60 defobj->strtab + def->st_name, (void *)new_value)); 61 u[obj->local_gotno + a0 - obj->gotsym] = new_value; 62 return ((caddr_t)new_value); 63 } 64 65 void 66 _rtld_setup_pltgot(obj) 67 const Obj_Entry *obj; 68 { 69 obj->pltgot[0] = (Elf_Addr) &_rtld_bind_start; 70 /* XXX only if obj->pltgot[1] & 0x80000000 ?? */ 71 obj->pltgot[1] |= (Elf_Addr) obj; 72 } 73 74 void 75 _rtld_relocate_nonplt_self(dynp, relocbase) 76 Elf_Dyn *dynp; 77 Elf_Addr relocbase; 78 { 79 const Elf_Rel *rel = 0, *rellim; 80 Elf_Addr relsz = 0; 81 Elf_Addr *where; 82 const Elf_Sym *symtab, *sym; 83 Elf_Addr *got; 84 Elf_Word local_gotno, symtabno, gotsym; 85 int i; 86 87 for (; dynp->d_tag != DT_NULL; dynp++) { 88 switch (dynp->d_tag) { 89 case DT_REL: 90 rel = (const Elf_Rel *)(relocbase + dynp->d_un.d_ptr); 91 break; 92 case DT_RELSZ: 93 relsz = dynp->d_un.d_val; 94 break; 95 case DT_SYMTAB: 96 symtab = (const Elf_Sym *)(relocbase + dynp->d_un.d_ptr); 97 break; 98 case DT_PLTGOT: 99 got = (Elf_Addr *)(relocbase + dynp->d_un.d_ptr); 100 break; 101 case DT_MIPS_LOCAL_GOTNO: 102 local_gotno = dynp->d_un.d_val; 103 break; 104 case DT_MIPS_SYMTABNO: 105 symtabno = dynp->d_un.d_val; 106 break; 107 case DT_MIPS_GOTSYM: 108 gotsym = dynp->d_un.d_val; 109 break; 110 } 111 } 112 rellim = (const Elf_Rel *)((caddr_t)rel + relsz); 113 for (; rel < rellim; rel++) { 114 where = (Elf_Addr *)(relocbase + rel->r_offset); 115 116 switch (ELF_R_TYPE(rel->r_info)) { 117 case R_TYPE(NONE): 118 break; 119 120 case R_TYPE(REL32): 121 sym = symtab + ELF_R_SYM(rel->r_info); 122 if (ELF_ST_BIND(sym->st_info) == STB_LOCAL && 123 ELF_ST_TYPE(sym->st_info) == STT_SECTION) 124 *where += (Elf_Addr)(sym->st_value + relocbase); 125 else 126 abort(); 127 break; 128 129 default: 130 abort(); 131 } 132 } 133 134 i = (got[1] & 0x80000000) ? 2 : 1; 135 /* Relocate the local GOT entries */ 136 got += i; 137 for (; i < local_gotno; i++) 138 *got++ += relocbase; 139 sym = symtab + gotsym; 140 /* Now do the global GOT entries */ 141 for (i = gotsym; i < symtabno; i++) { 142 if (sym->st_shndx == SHN_UNDEF || 143 sym->st_shndx == SHN_COMMON) 144 *got = sym->st_value + relocbase; 145 else if (ELF_ST_TYPE(sym->st_info) == STT_FUNC) 146 *got += relocbase; 147 else if (ELF_ST_TYPE(sym->st_info) == STT_SECTION && 148 ELF_ST_BIND(sym->st_info) == STB_GLOBAL) { 149 if (sym->st_shndx == SHN_ABS) 150 *got = sym->st_value + relocbase; 151 /* else SGI stuff ignored */ 152 } else 153 *got = sym->st_value + relocbase; 154 ++sym; 155 ++got; 156 } 157 } 158 159 int 160 _rtld_relocate_nonplt_objects(obj, self) 161 const Obj_Entry *obj; 162 bool self; 163 { 164 const Elf_Rel *rel; 165 Elf_Addr *got = obj->pltgot; 166 const Elf_Sym *sym, *def; 167 const Obj_Entry *defobj; 168 int i; 169 170 if (self) 171 return 0; 172 173 for (rel = obj->rel; rel < obj->rellim; rel++) { 174 Elf_Addr *where; 175 unsigned long symnum; 176 177 where = (Elf_Addr *)(obj->relocbase + rel->r_offset); 178 symnum = ELF_R_SYM(rel->r_info); 179 180 switch (ELF_R_TYPE(rel->r_info)) { 181 case R_TYPE(NONE): 182 break; 183 184 case R_TYPE(REL32): 185 /* 32-bit PC-relative reference */ 186 def = obj->symtab + symnum; 187 188 if (ELF_ST_BIND(def->st_info) == STB_LOCAL && 189 (ELF_ST_TYPE(def->st_info) == STT_SECTION || 190 ELF_ST_TYPE(def->st_info) == STT_NOTYPE)) { 191 /* 192 * XXX: ABI DIFFERENCE! 193 * 194 * Old NetBSD binutils would generate shared 195 * libs with section-relative relocations being 196 * already adjusted for the start address of 197 * the section. 198 * 199 * New binutils, OTOH, generate shared libs 200 * with the same relocations being based at 201 * zero, so we need to add in the start address 202 * of the section. 203 * 204 * We assume that all section-relative relocs 205 * with contents less than the start of the 206 * section need to be adjusted; this should 207 * work with both old and new shlibs. 208 * 209 * --rkb, Oct 6, 2001 210 */ 211 if (def->st_info == STT_SECTION && 212 *where < def->st_value) 213 *where += (Elf_Addr)def->st_value; 214 215 *where += (Elf_Addr)obj->relocbase; 216 217 rdbg(("REL32 %s in %s --> %p in %s", 218 obj->strtab + def->st_name, obj->path, 219 (void *)*where, obj->path)); 220 } else { 221 def = _rtld_find_symdef(symnum, obj, &defobj, 222 false); 223 if (def == NULL) 224 return -1; 225 *where += (Elf_Addr)(defobj->relocbase + 226 def->st_value); 227 rdbg(("REL32 %s in %s --> %p in %s", 228 obj->strtab + obj->symtab[symnum].st_name, 229 obj->path, (void *)*where, defobj->path)); 230 } 231 break; 232 233 default: 234 rdbg(("sym = %lu, type = %lu, offset = %p, " 235 "contents = %p, symbol = %s", 236 symnum, (u_long)ELF_R_TYPE(rel->r_info), 237 (void *)rel->r_offset, (void *)*where, 238 obj->strtab + obj->symtab[symnum].st_name)); 239 _rtld_error("%s: Unsupported relocation type %ld " 240 "in non-PLT relocations\n", 241 obj->path, (u_long) ELF_R_TYPE(rel->r_info)); 242 return -1; 243 } 244 } 245 246 i = (got[1] & 0x80000000) ? 2 : 1; 247 /* Relocate the local GOT entries */ 248 got += i; 249 for (; i < obj->local_gotno; i++) 250 *got++ += (Elf_Addr)obj->relocbase; 251 sym = obj->symtab + obj->gotsym; 252 /* Now do the global GOT entries */ 253 for (i = obj->gotsym; i < obj->symtabno; i++) { 254 rdbg((" doing got %d sym %p (%s, %x)", i - obj->gotsym, sym, 255 sym->st_name + obj->strtab, *got)); 256 257 if (sym->st_shndx == SHN_UNDEF && 258 ELF_ST_BIND(sym->st_info) != STB_WEAK && 259 ELF_ST_TYPE(sym->st_info) == STT_FUNC) 260 *got = sym->st_value + (Elf_Addr)obj->relocbase; 261 else if (sym->st_shndx == SHN_UNDEF || 262 sym->st_shndx == SHN_COMMON) { 263 def = _rtld_find_symdef(i, obj, &defobj, true); 264 if (def == NULL) 265 return -1; 266 *got = def->st_value + (Elf_Addr)defobj->relocbase; 267 } else if (ELF_ST_TYPE(sym->st_info) == STT_FUNC) 268 *got += (Elf_Addr)obj->relocbase; 269 else if (ELF_ST_TYPE(sym->st_info) == STT_SECTION && 270 ELF_ST_BIND(sym->st_info) == STB_GLOBAL) { 271 if (sym->st_shndx == SHN_ABS) 272 *got = sym->st_value + 273 (Elf_Addr)obj->relocbase; 274 /* else SGI stuff ignored */ 275 } else { 276 def = _rtld_find_symdef(i, obj, &defobj, true); 277 if (def == NULL) 278 return -1; 279 *got = def->st_value + (Elf_Addr)defobj->relocbase; 280 } 281 ++sym; 282 ++got; 283 } 284 285 return 0; 286 } 287 288 int 289 _rtld_relocate_plt_lazy(obj) 290 const Obj_Entry *obj; 291 { 292 } 293
Indexes created Tue Sep 30 20:09:53 GMT 2025