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/* vi: set sw=4 ts=4: */

/* m68k ELF shared library loader suppport

 *

 * Copyright (c) 1994-2000 Eric Youngdale, Peter MacDonald,

 *                              David Engel, Hongjiu Lu and Mitch D'Souza

 * Adapted to ELF/68k by Andreas Schwab.

 *

 * All rights reserved.

 *

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. The name of the above contributors may not be

 *    used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE CONTRIBUTORS ``AS IS'' AND

 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE

 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE

 * ARE DISCLAIMED.  IN NO EVENT SHALL THE CONTRIBUTORS BE LIABLE

 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL

 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS

 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)

 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT

 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY

 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF

 * SUCH DAMAGE.

 */

#if defined (__SUPPORT_LD_DEBUG__)

static const char *_dl_reltypes[] =

{

  "R_68K_NONE",

  "R_68K_32", "R_68K_16", "R_68K_8",

  "R_68K_PC32", "R_68K_PC16", "R_68K_PC8",

  "R_68K_GOT32", "R_68K_GOT16", "R_68K_GOT8",

  "R_68K_GOT32O", "R_68K_GOT16O", "R_68K_GOT8O",

  "R_68K_PLT32", "R_68K_PLT16", "R_68K_PLT8",

  "R_68K_PLT32O", "R_68K_PLT16O", "R_68K_PLT8O",

  "R_68K_COPY", "R_68K_GLOB_DAT", "R_68K_JMP_SLOT", "R_68K_RELATIVE",

  "R_68K_NUM"

};

#endif

/* Program to load an ELF binary on a linux system, and run it.

   References to symbols in sharable libraries can be resolved by either

   an ELF sharable library or a linux style of shared library. */

/* Disclaimer:  I have never seen any AT&T source code for SVr4, nor have

   I ever taken any courses on internals.  This program was developed using

   information available through the book "UNIX SYSTEM V RELEASE 4,

   Programmers guide: Ansi C and Programming Support Tools", which did

   a more than adequate job of explaining everything required to get this

   working. */

unsigned int _dl_linux_resolver (int dummy1, int dummy2,

        struct elf_resolve *tpnt, int reloc_entry)

{

  int reloc_type;

  Elf32_Rela *this_reloc;

  char *strtab;

  Elf32_Sym *symtab;

  char *rel_addr;

  int symtab_index;

  char *new_addr;

  char **got_addr;

  unsigned int instr_addr;

  rel_addr = tpnt->loadaddr + tpnt->dynamic_info[DT_JMPREL];

  this_reloc = (Elf32_Rela *) (rel_addr + reloc_entry);

  reloc_type = ELF32_R_TYPE (this_reloc->r_info);

  symtab_index = ELF32_R_SYM (this_reloc->r_info);

  symtab = (Elf32_Sym *) (tpnt->dynamic_info[DT_SYMTAB]

                                 + tpnt->loadaddr);

  strtab = (char *) (tpnt->dynamic_info[DT_STRTAB] + tpnt->loadaddr);

  if (reloc_type != R_68K_JMP_SLOT)

    {

      _dl_dprintf (2, "%s: incorrect relocation type in jump relocations\n",

                    _dl_progname);

      _dl_exit (1);

    }

  /* Address of jump instruction to fix up.  */

  instr_addr = (int) this_reloc->r_offset + (int) tpnt->loadaddr;

  got_addr = (char **) instr_addr;

#ifdef __SUPPORT_LD_DEBUG__

  if (_dl_debug_symbols) {

          _dl_dprintf (2, "Resolving symbol %s\n", strtab + symtab[symtab_index].st_name);

  }

#endif

  /* Get the address of the GOT entry.  */

  new_addr = _dl_find_hash (strtab + symtab[symtab_index].st_name,

                            tpnt->symbol_scope, tpnt, resolver);

  if (!new_addr)

    {

      _dl_dprintf (2, "%s: can't resolve symbol '%s'\n",

                    _dl_progname, strtab + symtab[symtab_index].st_name);

      _dl_exit (1);

    }

#if defined (__SUPPORT_LD_DEBUG__)

        if ((unsigned long) got_addr < 0x40000000)

        {

                if (_dl_debug_bindings)

                {

                        _dl_dprintf(_dl_debug_file, "\nresolve function: %s",

                                        strtab + symtab[symtab_index].st_name);

                        if(_dl_debug_detail) _dl_dprintf(_dl_debug_file,

                                        "\tpatch %x ==> %x @ %x", *got_addr, new_addr, got_addr);

                }

        }

        if (!_dl_debug_nofixups) {

                *got_addr = new_addr;

        }

#else

        *got_addr = new_addr;

#endif

  return (unsigned int) new_addr;

}

void

_dl_parse_lazy_relocation_information (struct elf_resolve *tpnt,

                       unsigned long rel_addr, unsigned long rel_size, int type)

{

  int i;

  char *strtab;

  int reloc_type;

  int symtab_index;

  Elf32_Sym *symtab;

  Elf32_Rela *rpnt;

  unsigned int *reloc_addr;

  /* Now parse the relocation information.  */

  rpnt = (Elf32_Rela *) (rel_addr + tpnt->loadaddr);

  rel_size = rel_size / sizeof (Elf32_Rela);

  symtab = (Elf32_Sym *) (tpnt->dynamic_info[DT_SYMTAB]

                                 + tpnt->loadaddr);

  strtab = (char *) (tpnt->dynamic_info[DT_STRTAB] + tpnt->loadaddr);

  for (i = 0; i < rel_size; i++, rpnt++)

    {

      reloc_addr = (int *) (tpnt->loadaddr + (int) rpnt->r_offset);

      reloc_type = ELF32_R_TYPE (rpnt->r_info);

      symtab_index = ELF32_R_SYM (rpnt->r_info);

      /* When the dynamic linker bootstrapped itself, it resolved some symbols.

         Make sure we do not do them again.  */

      if (tpnt->libtype == program_interpreter

          && (!symtab_index

              || _dl_symbol (strtab + symtab[symtab_index].st_name)))

        continue;

      switch (reloc_type)

        {

        case R_68K_NONE:

          break;

        case R_68K_JMP_SLOT:

          *reloc_addr += (unsigned int) tpnt->loadaddr;

          break;

        default:

          _dl_dprintf (2, "%s: (LAZY) can't handle reloc type ", _dl_progname);

#if defined (__SUPPORT_LD_DEBUG__)

          _dl_dprintf (2, "%s ", _dl_reltypes[reloc_type]);

#endif

          if (symtab_index)

            _dl_dprintf (2, "'%s'", strtab + symtab[symtab_index].st_name);

          _dl_dprintf (2, "\n");

          _dl_exit (1);

        }

    }

}

int

_dl_parse_relocation_information (struct elf_resolve *tpnt,

                  unsigned long rel_addr, unsigned long rel_size, int type)

{

  int i;

  char *strtab;

  int reloc_type;

  int goof = 0;

  Elf32_Sym *symtab;

  Elf32_Rela *rpnt;

  unsigned int *reloc_addr;

  unsigned int symbol_addr;

  int symtab_index;

  /* Now parse the relocation information */

  rpnt = (Elf32_Rela *) (rel_addr + tpnt->loadaddr);

  rel_size = rel_size / sizeof (Elf32_Rela);

  symtab = (Elf32_Sym *) (tpnt->dynamic_info[DT_SYMTAB]

                                 + tpnt->loadaddr);

  strtab = (char *) (tpnt->dynamic_info[DT_STRTAB] + tpnt->loadaddr);

  for (i = 0; i < rel_size; i++, rpnt++)

    {

      reloc_addr = (int *) (tpnt->loadaddr + (int) rpnt->r_offset);

      reloc_type = ELF32_R_TYPE (rpnt->r_info);

      symtab_index = ELF32_R_SYM (rpnt->r_info);

      symbol_addr = 0;

      if (tpnt->libtype == program_interpreter

          && (!symtab_index

              || _dl_symbol (strtab + symtab[symtab_index].st_name)))

        continue;

      if (symtab_index)

        {

          symbol_addr = (unsigned int)

            _dl_find_hash (strtab + symtab[symtab_index].st_name,

                           tpnt->symbol_scope,

                           reloc_type == R_68K_JMP_SLOT ? tpnt : NULL, symbolrel);

          /* We want to allow undefined references to weak symbols -

             this might have been intentional.  We should not be

             linking local symbols here, so all bases should be

             covered.  */

          if (!symbol_addr

              && ELF32_ST_BIND (symtab[symtab_index].st_info) == STB_GLOBAL)

            {

              _dl_dprintf (2, "%s: can't resolve symbol '%s'\n",

                            _dl_progname, strtab + symtab[symtab_index].st_name);

              goof++;

            }

        }

      switch (reloc_type)

        {

        case R_68K_NONE:

          break;

        case R_68K_8:

          *(char *) reloc_addr = symbol_addr + rpnt->r_addend;

          break;

        case R_68K_16:

          *(short *) reloc_addr = symbol_addr + rpnt->r_addend;

          break;

        case R_68K_32:

          *reloc_addr = symbol_addr + rpnt->r_addend;

          break;

        case R_68K_PC8:

          *(char *) reloc_addr = (symbol_addr + rpnt->r_addend

                                  - (unsigned int) reloc_addr);

          break;

        case R_68K_PC16:

          *(short *) reloc_addr = (symbol_addr + rpnt->r_addend

                                   - (unsigned int) reloc_addr);

          break;

        case R_68K_PC32:

          *reloc_addr = (symbol_addr + rpnt->r_addend

                         - (unsigned int) reloc_addr);

          break;

        case R_68K_GLOB_DAT:

        case R_68K_JMP_SLOT:

          *reloc_addr = symbol_addr;

          break;

        case R_68K_RELATIVE:

          *reloc_addr = ((unsigned int) tpnt->loadaddr

                         /* Compatibility kludge.  */

                         + (rpnt->r_addend ? : *reloc_addr));

          break;

        case R_68K_COPY:

#if 0 /* Do this later.  */

          _dl_dprintf (2, "Doing copy");

          if (symtab_index)

            _dl_dprintf (2, " for symbol %s",

                          strtab + symtab[symtab_index].st_name);

          _dl_dprintf (2, "\n");

          _dl_memcpy ((void *) symtab[symtab_index].st_value,

                      (void *) symbol_addr,

                      symtab[symtab_index].st_size);

#endif

          break;

        default:

          _dl_dprintf (2, "%s: can't handle reloc type ", _dl_progname);

#if defined (__SUPPORT_LD_DEBUG__)

          _dl_dprintf (2, "%s ", _dl_reltypes[reloc_type]);

#endif

          if (symtab_index)

            _dl_dprintf (2, "'%s'", strtab + symtab[symtab_index].st_name);

          _dl_dprintf (2, "\n");

          _dl_exit (1);

        }

    }

  return goof;

}

/* This is done as a separate step, because there are cases where

   information is first copied and later initialized.  This results in

   the wrong information being copied.  Someone at Sun was complaining about

   a bug in the handling of _COPY by SVr4, and this may in fact be what he

   was talking about.  Sigh.  */

/* No, there are cases where the SVr4 linker fails to emit COPY relocs

   at all.  */

int

_dl_parse_copy_information (struct dyn_elf *xpnt, unsigned long rel_addr,

                            unsigned long rel_size, int type)

{

  int i;

  char *strtab;

  int reloc_type;

  int goof = 0;

  Elf32_Sym *symtab;

  Elf32_Rela *rpnt;

  unsigned int *reloc_addr;

  unsigned int symbol_addr;

  struct elf_resolve *tpnt;

  int symtab_index;

  /* Now parse the relocation information */

  tpnt = xpnt->dyn;

  rpnt = (Elf32_Rela *) (rel_addr + tpnt->loadaddr);

  rel_size = rel_size / sizeof (Elf32_Rela);

  symtab = (Elf32_Sym *) (tpnt->dynamic_info[DT_SYMTAB]

                                 + tpnt->loadaddr);

  strtab = (char *) (tpnt->dynamic_info[DT_STRTAB] + tpnt->loadaddr);

  for (i = 0; i < rel_size; i++, rpnt++)

    {

      reloc_addr = (int *) (tpnt->loadaddr + (int) rpnt->r_offset);

      reloc_type = ELF32_R_TYPE (rpnt->r_info);

      if (reloc_type != R_68K_COPY)

        continue;

      symtab_index = ELF32_R_SYM (rpnt->r_info);

      symbol_addr = 0;

      if (tpnt->libtype == program_interpreter

          && (!symtab_index

              || _dl_symbol (strtab + symtab[symtab_index].st_name)))

        continue;

      if (symtab_index)

        {

          symbol_addr = (unsigned int)

            _dl_find_hash (strtab + symtab[symtab_index].st_name,

                           xpnt->next, NULL, copyrel);

          if (!symbol_addr)

            {

              _dl_dprintf (2, "%s: can't resolve symbol '%s'\n",

                            _dl_progname, strtab + symtab[symtab_index].st_name);

              goof++;

            }

        }

      if (!goof)

      _dl_memcpy ((void *) symtab[symtab_index].st_value, (void *) symbol_addr,

                  symtab[symtab_index].st_size);

    }

  return goof;

}