l4/pkg/uclibc/lib/contrib/uclibc/ldso/ldso/avr32/elfinterp.c

   1 /*
   2  * AVR32 ELF shared library loader suppport
   3  *
   4  * Copyright (C) 2004-2006 Atmel Corporation
   5  *
   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. The name of the above contributors may not be
  14  *    used to endorse or promote products derived from this software
  15  *    without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND
  18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE
  21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  27  * SUCH DAMAGE.
  28  */
  29
  30 unsigned long _dl_linux_resolver(unsigned long got_offset, unsigned long *got)
  31 {
  32         /*
  33          * AVR32 currently does not do lazy relocation.
  34          */
  35 #if 0
  36         struct elf_resolve *tpnt = (struct elf_resolve *)got[1];
  37         ElfW(Sym) *sym;
  38         unsigned long local_gotno;
  39         unsigned long gotsym;
  40         unsigned long new_addr;
  41         char *strtab, *symname;
  42         unsigned long *entry;
  43         unsigned long sym_index = got_offset / 4;
  44
  45         local_gotno = tpnt->dynamic_info[DT_AVR32_LOCAL_GOTNO];
  46         gotsym = tpnt->dynamic_info[DT_AVR32_GOTSYM];
  47
  48         sym = ((ElfW(Sym) *)(tpnt->dynamic_info[DT_SYMTAB] + tpnt->loadaddr))
  49                 + sym_index;
  50         strtab = (char *)(tpnt->dynamic_info[DT_STRTAB] + tpnt->loadaddr);
  51         symname = strtab + sym->st_name;
  52
  53         new_addr = (unsigned long) _dl_find_hash(symname,
  54                                                  &_dl_loaded_modules->symbol_scope, tpnt,
  55                                                  ELF_RTYPE_CLASS_PLT, NULL);
  56
  57         entry = (unsigned long *)(got + local_gotno + sym_index - gotsym);
  58         *entry = new_addr;
  59
  60         return new_addr;
  61 #endif
  62         return 0;
  63 }
  64
  65 static int
  66 _dl_parse(struct elf_resolve *tpnt, struct r_scope_elem *scope,
  67           unsigned long rel_addr, unsigned long rel_size,
  68           int (*reloc_func)(struct elf_resolve *tpnt, struct r_scope_elem *scope,
  69                             ElfW(Rela) *rpnt, ElfW(Sym) *symtab, char *strtab))
  70 {
  71         ElfW(Sym) *symtab;
  72         ElfW(Rela) *rpnt;
  73         char *strtab;
  74         int i;
  75
  76         rpnt = (ElfW(Rela) *)rel_addr;
  77         rel_size /= sizeof(ElfW(Rela));
  78         symtab = (ElfW(Sym) *)tpnt->dynamic_info[DT_SYMTAB];
  79         strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
  80
  81         for (i = 0; i < rel_size; i++, rpnt++) {
  82                 int symtab_index, res;
  83
  84                 symtab_index = ELF_R_SYM(rpnt->r_info);
  85
  86                 debug_sym(symtab, strtab, symtab_index);
  87                 debug_reloc(symtab, strtab, rpnt);
  88
  89                 res = reloc_func(tpnt, scope, rpnt, symtab, strtab);
  90
  91                 if (res == 0)
  92                         continue;
  93
  94                 _dl_dprintf(2, "\n%s: ", _dl_progname);
  95
  96                 if (symtab_index)
  97                         _dl_dprintf(2, "symbol '%s': ",
  98                                     strtab + symtab[symtab_index].st_name);
  99
 100                 if (res < 0) {
 101                         int reloc_type = ELF_R_TYPE(rpnt->r_info);
 102 #if defined(__SUPPORT_LD_DEBUG__)
 103                         _dl_dprintf(2, "can't handle reloc type %s\n",
 104                                     _dl_reltypes(reloc_type));
 105 #else
 106                         _dl_dprintf(2, "can't handle reloc type %x\n",
 107                                     reloc_type);
 108 #endif
 109                         _dl_exit(-res);
 110                 } else {
 111                         _dl_dprintf(2, "can't resolve symbol\n");
 112                         return res;
 113                 }
 114         }
 115
 116         return 0;
 117 }
 118
 119 static int _dl_do_reloc(struct elf_resolve *tpnt, struct r_scope_elem *scope,
 120                         ElfW(Rela) *rpnt, ElfW(Sym) *symtab, char *strtab)
 121 {
 122         int reloc_type;
 123         int symtab_index;
 124         char *symname;
 125         unsigned long *reloc_addr;
 126         unsigned long symbol_addr;
 127 #if defined(__SUPPORT_LD_DEBUG__)
 128         unsigned long old_val;
 129 #endif
 130         struct symbol_ref sym_ref;
 131
 132         reloc_addr = (unsigned long *)(tpnt->loadaddr + rpnt->r_offset);
 133         reloc_type = ELF_R_TYPE(rpnt->r_info);
 134         symtab_index = ELF_R_SYM(rpnt->r_info);
 135         symbol_addr = 0;
 136         sym_ref.sym = &symtab[symtab_index];
 137         sym_ref.tpnt = NULL;
 138         symname = strtab + symtab[symtab_index].st_name;
 139
 140         if (symtab_index) {
 141                 symbol_addr = (unsigned long)
 142                         _dl_find_hash(symname, scope, tpnt,
 143                                       elf_machine_type_class(reloc_type), &sym_ref);
 144
 145                 /* Allow undefined references to weak symbols */
 146                 if (!symbol_addr &&
 147                     ELF_ST_BIND(symtab[symtab_index].st_info) != STB_WEAK) {
 148                         _dl_dprintf(2, "%s: can't resolve symbol '%s'\n",
 149                                     _dl_progname, symname);
 150                         return 0;
 151                 }
 152                 if (_dl_trace_prelink) {
 153                         _dl_debug_lookup (symname, tpnt, &symtab[symtab_index],
 154                                 &sym_ref, elf_machine_type_class(reloc_type));
 155                 }
 156         }
 157
 158 #if defined(__SUPPORT_LD_DEBUG__)
 159         old_val = *reloc_addr;
 160 #endif
 161         switch (reloc_type) {
 162         case R_AVR32_NONE:
 163                 break;
 164         case R_AVR32_GLOB_DAT:
 165         case R_AVR32_JMP_SLOT:
 166                 *reloc_addr = symbol_addr + rpnt->r_addend;
 167                 break;
 168         case R_AVR32_RELATIVE:
 169                 *reloc_addr = (unsigned long)tpnt->loadaddr
 170                         + rpnt->r_addend;
 171                 break;
 172         default:
 173                 return -1;
 174         }
 175
 176 #if defined(__SUPPORT_LD_DEBUG__)
 177         if (_dl_debug_reloc && _dl_debug_detail)
 178                 _dl_dprintf(_dl_debug_file, "\tpatched: %x ==> %x @ %x\n",
 179                             old_val, *reloc_addr);
 180 #endif
 181
 182         return 0;
 183 }
 184
 185 void _dl_parse_lazy_relocation_information(struct dyn_elf *rpnt,
 186                                            unsigned long rel_addr,
 187                                            unsigned long rel_size)
 188 {
 189         /* TODO: Might want to support this in order to get faster
 190          * startup times... */
 191 }
 192
 193 int _dl_parse_relocation_information(struct dyn_elf *rpnt,
 194                                      struct r_scope_elem *scope,
 195                                      unsigned long rel_addr,
 196                                      unsigned long rel_size)
 197 {
 198         return _dl_parse(rpnt->dyn, scope, rel_addr, rel_size,
 199                          _dl_do_reloc);
 200 }