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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.
*/
/* 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 int _dl_linux_resolve(void);
unsigned int
_dl_linux_resolver(struct elf_resolve *tpnt, int reloc_entry)
{
int reloc_type;
ELF_RELOC *this_reloc;
char *strtab;
Elf32_Sym *symtab;
int symtab_index;
ELF_RELOC *rel_addr;
char *new_addr;
char **got_addr;
unsigned int instr_addr;
char *symname;
rel_addr = (ELF_RELOC *)tpnt->dynamic_info[DT_JMPREL];
this_reloc = (ELF_RELOC *)(intptr_t)(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 *)(intptr_t)tpnt->dynamic_info[DT_SYMTAB];
strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
symname = strtab + symtab[symtab_index].st_name;
if (unlikely(reloc_type != R_68K_JMP_SLOT)) {
_dl_dprintf(2, "%s: Incorrect relocation type in jump relocations\n",
_dl_progname);
_dl_exit(1);
}
/* Address of the jump instruction to fix up. */
instr_addr = ((int)this_reloc->r_offset + (int)tpnt->loadaddr);
got_addr = (char **)instr_addr;
/* Get the address of the GOT entry. */
new_addr = _dl_find_hash(symname, tpnt->symbol_scope, tpnt, ELF_RTYPE_CLASS_PLT);
if (unlikely(!new_addr)) {
_dl_dprintf(2, "%s: Can't resolve symbol '%s'\n", _dl_progname, symname);
_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", symname);
if (_dl_debug_detail)
_dl_dprintf(_dl_debug_file,
"\n\tpatched: %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 dyn_elf *arg_rpnt,
unsigned long rel_addr, unsigned long rel_size)
{
int i;
char *strtab;
int reloc_type;
int symtab_index;
Elf32_Sym *symtab;
Elf32_Rela *rpnt;
unsigned int *reloc_addr;
struct elf_resolve *tpnt = arg_rpnt->dyn;
/* Now parse the relocation information. */
rpnt = (Elf32_Rela *)rel_addr;
rel_size = rel_size / sizeof (Elf32_Rela);
symtab = (Elf32_Sym *)tpnt->dynamic_info[DT_SYMTAB];
strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
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);
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_tab[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 dyn_elf *arg_rpnt,
unsigned long rel_addr, unsigned long rel_size)
{
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;
struct elf_resolve *tpnt = arg_rpnt->dyn;
/* Now parse the relocation information */
rpnt = (Elf32_Rela *)rel_addr;
rel_size = rel_size / sizeof (Elf32_Rela);
symtab = (Elf32_Sym *)tpnt->dynamic_info[DT_SYMTAB];
strtab = (char *)tpnt->dynamic_info[DT_STRTAB];
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 (symtab_index) {
symbol_addr = (unsigned int)
_dl_find_hash (strtab + symtab[symtab_index].st_name,
tpnt->symbol_scope, tpnt,
elf_machine_type_class(reloc_type));
/* 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_WEAK)
{
_dl_dprintf (2, "%s: can't resolve symbol '%s'\n",
_dl_progname, strtab + symtab[symtab_index].st_name);
_dl_exit (1);
}
}
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:
_dl_memcpy ((void *) reloc_addr,
(void *) symbol_addr,
symtab[symtab_index].st_size);
break;
default:
_dl_dprintf (2, "%s: can't handle reloc type ", _dl_progname);
#if defined (__SUPPORT_LD_DEBUG__)
_dl_dprintf (2, "%s ", _dl_reltypes_tab[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;
}
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