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

/* sparc ELF shared library loader suppport

 *

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

 *                              David Engel, Hongjiu Lu and Mitch D'Souza

 *

 * 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_SPARC_NONE", "R_SPARC_8",

  "R_SPARC_16", "R_SPARC_32", "R_SPARC_DISP8", "R_SPARC_DISP16",

  "R_SPARC_DISP32", "R_SPARC_WDISP30", "R_SPARC_WDISP22",

  "R_SPARC_HI22", "R_SPARC_22", "R_SPARC_13", "R_SPARC_LO10",

  "R_SPARC_GOT10", "R_SPARC_GOT13", "R_SPARC_GOT22", "R_SPARC_PC10",

  "R_SPARC_PC22", "R_SPARC_WPLT30", "R_SPARC_COPY",

  "R_SPARC_GLOB_DAT", "R_SPARC_JMP_SLOT", "R_SPARC_RELATIVE",

  "R_SPARC_UA32"};

#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. */

extern _dl_linux_resolve(void);

unsigned int _dl_linux_resolver(unsigned int reloc_entry, unsigned int * plt)

{

  int reloc_type;

  Elf32_Rela * this_reloc;

  char * strtab;

  Elf32_Sym * symtab;

  Elf32_Rela * rel_addr;

  struct elf_resolve * tpnt;

  int symtab_index;

  char * new_addr;

  char ** got_addr;

  unsigned int instr_addr;

  tpnt = (struct elf_resolve *) plt[2];

  rel_addr = (Elf32_Rela *) (tpnt->dynamic_info[DT_JMPREL] +

                                   tpnt->loadaddr);

  /*

   * Generate the correct relocation index into the .rela.plt section.

   */

  reloc_entry = (reloc_entry >> 12) - 0xc;

  this_reloc = (Elf32_Rela *) ((char *) 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);

  _dl_dprintf(2, "tpnt = %x\n", tpnt);

  _dl_dprintf(2, "reloc = %x\n", this_reloc);

  _dl_dprintf(2, "symtab = %x\n", symtab);

  _dl_dprintf(2, "strtab = %x\n", strtab);

  if (reloc_type != R_SPARC_JMP_SLOT) {

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

                  _dl_progname, reloc_type);

    _dl_exit(30);

  };

  /* Address of jump instruction to fix up */

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

  got_addr = (char **) instr_addr;

  _dl_dprintf(2, "symtab_index %d\n", symtab_index);

#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(31);

  };

#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[1] = (char *) (0x03000000 | (((unsigned int) new_addr >> 10) & 0x3fffff));

                got_addr[2] = (char *) (0x81c06000 | ((unsigned int) new_addr & 0x3ff));

        }

#else

        got_addr[1] = (char *) (0x03000000 | (((unsigned int) new_addr >> 10) & 0x3fffff));

        got_addr[2] = (char *) (0x81c06000 | ((unsigned int) new_addr & 0x3ff));

#endif

        _dl_dprintf(2, "Address = %x\n",new_addr);

        _dl_exit(32);

  return (unsigned int) new_addr;

}

void _dl_parse_lazy_relocation_information(struct elf_resolve * tpnt, int rel_addr,

       int 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);

  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 += sizeof(Elf32_Rela), 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(!symtab_index && tpnt->libtype == program_interpreter) continue;

    if(symtab_index && tpnt->libtype == program_interpreter &&

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

      continue;

    switch(reloc_type){

    case R_SPARC_NONE:

      break;

    case R_SPARC_JMP_SLOT:

      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'\n",

                                  strtab + symtab[symtab_index].st_name);

      _dl_exit(33);

    };

  };

}

int _dl_parse_relocation_information(struct elf_resolve * tpnt, int rel_addr,

       int 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);

  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+= sizeof(Elf32_Rela), 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(!symtab_index && tpnt->libtype == program_interpreter) continue;

    if(symtab_index) {

      if(tpnt->libtype == program_interpreter &&

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

        continue;

      symbol_addr = (unsigned int)

        _dl_find_hash(strtab + symtab[symtab_index].st_name,

                              tpnt->symbol_scope,

                      (reloc_type == R_SPARC_JMP_SLOT ? tpnt : NULL), symbolrel);

      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_SPARC_NONE:

        break;

    case R_SPARC_32:

      *reloc_addr = symbol_addr + rpnt->r_addend;

      break;

    case R_SPARC_DISP32:

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

      break;

    case R_SPARC_GLOB_DAT:

      *reloc_addr = symbol_addr + rpnt->r_addend;

      break;

    case R_SPARC_JMP_SLOT:

      reloc_addr[1] = 0x03000000 | ((symbol_addr >> 10) & 0x3fffff);

      reloc_addr[2] = 0x81c06000 | (symbol_addr & 0x3ff);

      break;

    case R_SPARC_RELATIVE:

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

      break;

    case R_SPARC_HI22:

      if (!symbol_addr)

        symbol_addr = tpnt->loadaddr + rpnt->r_addend;

      else

        symbol_addr += rpnt->r_addend;

      *reloc_addr = (*reloc_addr & 0xffc00000)|(symbol_addr >> 10);

      break;

    case R_SPARC_LO10:

      if (!symbol_addr)

        symbol_addr = tpnt->loadaddr + rpnt->r_addend;

      else

        symbol_addr += rpnt->r_addend;

      *reloc_addr = (*reloc_addr & ~0x3ff)|(symbol_addr & 0x3ff);

      break;

    case R_SPARC_WDISP30:

      *reloc_addr = (*reloc_addr & 0xc0000000)|

        ((symbol_addr - (unsigned int) reloc_addr) >> 2);

      break;

    case R_SPARC_COPY:

#if 0 /* This one is done later */

      _dl_dprintf(2, "Doing copy for symbol ");

      if(symtab_index) _dl_dprintf(2, 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'\n", strtab + symtab[symtab_index].st_name);

      _dl_exit(34);

    };

  };

  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, int rel_addr,

       int 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);

  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+= sizeof(Elf32_Rela), rpnt++){

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

    reloc_type = ELF32_R_TYPE(rpnt->r_info);

    if(reloc_type != R_SPARC_COPY) continue;

    symtab_index = ELF32_R_SYM(rpnt->r_info);

    symbol_addr = 0;

    if(!symtab_index && tpnt->libtype == program_interpreter) continue;

    if(symtab_index) {

      if(tpnt->libtype == program_interpreter &&

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

        continue;

      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((char *) symtab[symtab_index].st_value,

                  (char *) symbol_addr,

                  symtab[symtab_index].st_size);

  };

  return goof;

}