libexec/ld.elf_so/arch/m68k/mdreloc.c

   1 /*      $NetBSD: mdreloc.c,v 1.23 2009/03/16 02:46:47 lukem Exp $       */
   2
   3 #include <sys/cdefs.h>
   4 #ifndef lint
   5 __RCSID("$NetBSD: mdreloc.c,v 1.23 2009/03/16 02:46:47 lukem Exp $");
   6 #endif /* not lint */
   7
   8 #include <sys/cdefs.h>
   9 #ifndef lint
  10 __RCSID("$NetBSD: mdreloc.c,v 1.23 2009/03/16 02:46:47 lukem Exp $");
  11 #endif /* not lint */
  12
  13 #include <sys/types.h>
  14 #include <sys/stat.h>
  15
  16 #include "debug.h"
  17 #include "rtld.h"
  18
  19 void _rtld_bind_start(void);
  20 void _rtld_relocate_nonplt_self(Elf_Dyn *, Elf_Addr);
  21 caddr_t _rtld_bind(const Obj_Entry *, Elf_Word);
  22 static inline int _rtld_relocate_plt_object(const Obj_Entry *,
  23     const Elf_Rela *, Elf_Addr *);
  24
  25
  26 void
  27 _rtld_setup_pltgot(const Obj_Entry *obj)
  28 {
  29         obj->pltgot[1] = (Elf_Addr) obj;
  30         obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start;
  31 }
  32
  33 void
  34 _rtld_relocate_nonplt_self(Elf_Dyn *dynp, Elf_Addr relocbase)
  35 {
  36         const Elf_Rela *rela = 0, *relalim;
  37         Elf_Addr relasz = 0;
  38         Elf_Addr *where;
  39
  40         for (; dynp->d_tag != DT_NULL; dynp++) {
  41                 switch (dynp->d_tag) {
  42                 case DT_RELA:
  43                         rela = (const Elf_Rela *)(relocbase + dynp->d_un.d_ptr);
  44                         break;
  45                 case DT_RELASZ:
  46                         relasz = dynp->d_un.d_val;
  47                         break;
  48                 }
  49         }
  50         relalim = (const Elf_Rela *)((const uint8_t *)rela + relasz);
  51         for (; rela < relalim; rela++) {
  52                 where = (Elf_Addr *)(relocbase + rela->r_offset);
  53                 *where += (Elf_Addr)relocbase;
  54         }
  55 }
  56
  57 int
  58 _rtld_relocate_nonplt_objects(const Obj_Entry *obj)
  59 {
  60         const Elf_Rela *rela;
  61
  62         for (rela = obj->rela; rela < obj->relalim; rela++) {
  63                 Elf_Addr        *where;
  64                 const Elf_Sym   *def;
  65                 const Obj_Entry *defobj;
  66                 Elf_Addr         tmp;
  67                 unsigned long    symnum;
  68
  69                 where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
  70                 symnum = ELF_R_SYM(rela->r_info);
  71
  72                 switch (ELF_R_TYPE(rela->r_info)) {
  73                 case R_TYPE(NONE):
  74                         break;
  75
  76 #if 1 /* XXX should not occur */
  77                 case R_TYPE(PC32):
  78                         def = _rtld_find_symdef(symnum, obj, &defobj, false);
  79                         if (def == NULL)
  80                                 return -1;
  81
  82                         tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
  83                             rela->r_addend) - (Elf_Addr)where;
  84                         if (*where != tmp)
  85                                 *where = tmp;
  86                         rdbg(("PC32 %s in %s --> %p in %s",
  87                             obj->strtab + obj->symtab[symnum].st_name,
  88                             obj->path, (void *)*where, defobj->path));
  89                         break;
  90
  91                 case R_TYPE(GOT32):
  92 #endif
  93                 case R_TYPE(32):
  94                 case R_TYPE(GLOB_DAT):
  95                         def = _rtld_find_symdef(symnum, obj, &defobj, false);
  96                         if (def == NULL)
  97                                 return -1;
  98
  99                         tmp = (Elf_Addr)(defobj->relocbase + def->st_value +
 100                             rela->r_addend);
 101                         if (*where != tmp)
 102                                 *where = tmp;
 103                         rdbg(("32/GLOB_DAT %s in %s --> %p in %s",
 104                             obj->strtab + obj->symtab[symnum].st_name,
 105                             obj->path, (void *)*where, defobj->path));
 106                         break;
 107
 108                 case R_TYPE(RELATIVE):
 109                         *where += (Elf_Addr)obj->relocbase;
 110                         rdbg(("RELATIVE in %s --> %p", obj->path,
 111                             (void *)*where));
 112                         break;
 113
 114                 case R_TYPE(COPY):
 115                         /*
 116                          * These are deferred until all other relocations have
 117                          * been done.  All we do here is make sure that the
 118                          * COPY relocation is not in a shared library.  They
 119                          * are allowed only in executable files.
 120                          */
 121                         if (obj->isdynamic) {
 122                                 _rtld_error(
 123                         "%s: Unexpected R_COPY relocation in shared library",
 124                                     obj->path);
 125                                 return -1;
 126                         }
 127                         rdbg(("COPY (avoid in main)"));
 128                         break;
 129
 130                 default:
 131                         rdbg(("sym = %lu, type = %lu, offset = %p, "
 132                             "addend = %p, contents = %p, symbol = %s",
 133                             symnum, (u_long)ELF_R_TYPE(rela->r_info),
 134                             (void *)rela->r_offset, (void *)rela->r_addend,
 135                             (void *)*where,
 136                             obj->strtab + obj->symtab[symnum].st_name));
 137                         _rtld_error("%s: Unsupported relocation type %ld "
 138                             "in non-PLT relocations",
 139                             obj->path, (u_long) ELF_R_TYPE(rela->r_info));
 140                         return -1;
 141                 }
 142         }
 143         return 0;
 144 }
 145
 146 int
 147 _rtld_relocate_plt_lazy(const Obj_Entry *obj)
 148 {
 149         const Elf_Rela *rela;
 150
 151         if (!obj->relocbase)
 152                 return 0;
 153
 154         for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) {
 155                 Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
 156
 157                 assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
 158
 159                 /* Just relocate the GOT slots pointing into the PLT */
 160                 *where += (Elf_Addr)obj->relocbase;
 161                 rdbg(("fixup !main in %s --> %p", obj->path, (void *)*where));
 162         }
 163
 164         return 0;
 165 }
 166
 167 static inline int
 168 _rtld_relocate_plt_object(const Obj_Entry *obj, const Elf_Rela *rela, Elf_Addr *tp)
 169 {
 170         Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
 171         Elf_Addr new_value;
 172         const Elf_Sym  *def;
 173         const Obj_Entry *defobj;
 174
 175         assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JMP_SLOT));
 176
 177         def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true);
 178         if (def == NULL)
 179                 return -1;
 180
 181         assert(rela->r_addend == 0);
 182         new_value = (Elf_Addr)(defobj->relocbase + def->st_value +
 183             rela->r_addend);
 184         rdbg(("bind now/fixup in %s --> old=%p new=%p",
 185             defobj->strtab + def->st_name, (void *)*where, (void *)new_value));
 186         if (*where != new_value)
 187                 *where = new_value;
 188
 189         if (tp)
 190                 *tp = new_value - rela->r_addend;
 191
 192         return 0;
 193 }
 194
 195 caddr_t
 196 _rtld_bind(const Obj_Entry *obj, Elf_Word reloff)
 197 {
 198         const Elf_Rela *rela = (const Elf_Rela *)((const uint8_t *)obj->pltrela + reloff);
 199         Elf_Addr result;
 200         int err;
 201
 202         result = 0;     /* XXX gcc */
 203
 204         err = _rtld_relocate_plt_object(obj, rela, &result);
 205         if (err || result == 0)
 206                 _rtld_die();
 207
 208         return (caddr_t)result;
 209 }
 210
 211 int
 212 _rtld_relocate_plt_objects(const Obj_Entry *obj)
 213 {
 214         const Elf_Rela *rela;
 215
 216         for (rela = obj->pltrela; rela < obj->pltrelalim; rela++)
 217                 if (_rtld_relocate_plt_object(obj, rela, NULL) < 0)
 218                         return -1;
 219
 220         return 0;
 221 }