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/* $OpenBSD: rtld_machine.c,v 1.14 2003/09/02 15:17:51 drahn Exp $ */
/*
* Copyright (c) 1998-2002 Opsycon AB, Sweden.
*
* 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. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``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 AUTHOR 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.
*
*/
#define _DYN_LOADER
#include <sys/types.h>
#include <link.h>
#include "resolve.h"
#include "syscall.h"
#include "archdep.h"
int
_dl_md_reloc(elf_object_t *object, int rel, int relsz)
{
int i;
int numrel;
int fails = 0;
Elf32_Addr loff;
Elf32_Rel *relocs;
loff = object->load_offs;
numrel = object->Dyn.info[relsz] / sizeof(Elf32_Rel);
relocs = (Elf32_Rel *)(object->Dyn.info[rel]);
if (relocs == NULL)
return(0);
for (i = 0; i < numrel; i++, relocs++) {
Elf32_Addr r_addr = relocs->r_offset + loff;
Elf32_Addr ooff = 0;
const Elf32_Sym *sym, *this;
const char *symn;
int type;
if (ELF32_R_SYM(relocs->r_info) == 0xffffff)
continue;
sym = object->dyn.symtab;
sym += ELF32_R_SYM(relocs->r_info);
this = sym;
symn = object->dyn.strtab + sym->st_name;
type = ELF32_R_TYPE(relocs->r_info);
if (ELF32_R_SYM(relocs->r_info) &&
!(ELF32_ST_BIND(sym->st_info) == STB_LOCAL &&
ELF32_ST_TYPE (sym->st_info) == STT_NOTYPE)) {
ooff = _dl_find_symbol(symn, _dl_objects, &this,
SYM_SEARCH_ALL | SYM_NOWARNNOTFOUND | SYM_PLT,
sym->st_size, object);
if (!this && ELF32_ST_BIND(sym->st_info) == STB_GLOBAL) {
_dl_printf("%s: can't resolve reference '%s'\n",
_dl_progname, symn);
fails++;
}
}
switch (ELF32_R_TYPE(relocs->r_info)) {
case R_MIPS_REL32:
if (ELF32_ST_BIND(sym->st_info) == STB_LOCAL &&
(ELF32_ST_TYPE(sym->st_info) == STT_SECTION ||
ELF32_ST_TYPE(sym->st_info) == STT_NOTYPE) ) {
*(u_int32_t *)r_addr += loff + sym->st_value;
} else if (this) {
*(u_int32_t *)r_addr += this->st_value + ooff;
}
break;
case R_MIPS_NONE:
break;
default:
_dl_printf("%s: unsupported relocation '%s'\n",
_dl_progname, symn);
_dl_exit(1);
}
}
return(fails);
}
/*
* Relocate the Global Offset Table (GOT). Currently we don't
* do lazy evaluation here because the GNU linker doesn't
* follow the ABI spec which says that if an external symbol
* is referenced by other relocations than CALL16 and 26 it
* should not be given a stub and have a zero value in the
* symbol table. By not doing so, we can't use pointers to
* external functions and use them in comparisons...
*/
void
_dl_md_reloc_got(elf_object_t *object, int lazy)
{
int i, n;
Elf32_Addr loff;
Elf32_Addr ooff;
Elf32_Addr *gotp;
const Elf32_Sym *symp;
const Elf32_Sym *this;
const char *strt;
Elf_Addr ooff;
const Elf_Sym *this;
if (object->status & STAT_GOT_DONE)
return;
lazy = 0; /* XXX Fix ld before enabling lazy */
loff = object->load_offs;
strt = object->dyn.strtab;
gotp = object->dyn.pltgot;
n = object->Dyn.info[DT_MIPS_LOCAL_GOTNO - DT_LOPROC + DT_NUM];
/*
* Set up pointers for run time (lazy) resolving.
*/
gotp[0] = (int)_dl_rt_resolve;
if (gotp[1] & 0x80000000) {
gotp[1] = (int)object | 0x80000000;
}
/* First do all local references. */
for (i = ((gotp[1] & 0x80000000) ? 2 : 1); i < n; i++) {
gotp[i] += loff;
}
gotp += n;
symp = object->dyn.symtab;
symp += object->Dyn.info[DT_MIPS_GOTSYM - DT_LOPROC + DT_NUM];
n = object->Dyn.info[DT_MIPS_SYMTABNO - DT_LOPROC + DT_NUM] -
object->Dyn.info[DT_MIPS_GOTSYM - DT_LOPROC + DT_NUM];
this = NULL;
ooff = _dl_find_symbol("__got_start", object, &this,
SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, 0, object);
if (this != NULL)
object->got_addr = ooff + this->st_value;
this = NULL;
ooff = _dl_find_symbol("__got_end", object, &this,
SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, 0, object);
if (this != NULL)
object->got_size = ooff + this->st_value - object->got_addr;
this = NULL;
ooff = _dl_find_symbol("__plt_start", object, &this,
SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, 0, object);
if (this != NULL)
object->plt_addr = ooff + this->st_value;
this = NULL;
ooff = _dl_find_symbol("__plt_end", object, &this,
SYM_SEARCH_SELF|SYM_NOWARNNOTFOUND|SYM_PLT, 0, object);
if (this != NULL)
object->plt_size = ooff + this->st_value - object->plt_addr;
/*
* Then do all global references according to the ABI.
* Quickstart is not yet implemented.
*/
while (n--) {
if (symp->st_shndx == SHN_UNDEF &&
ELF32_ST_TYPE(symp->st_info) == STT_FUNC) {
DL_DEB(("got: '%s' = %x\n", strt + symp->st_name, symp->st_value));
if (symp->st_value == 0 || !lazy) {
this = 0;
ooff = _dl_find_symbol(strt + symp->st_name,
_dl_objects, &this,
SYM_SEARCH_ALL|SYM_NOWARNNOTFOUND|SYM_PLT,
symp->st_size, object);
if (this)
*gotp = this->st_value + ooff;
} else
*gotp = symp->st_value + ooff;
} else if (symp->st_shndx == SHN_COMMON ||
symp->st_shndx == SHN_UNDEF) {
this = 0;
ooff = _dl_find_symbol(strt + symp->st_name,
_dl_objects, &this,
SYM_SEARCH_ALL|SYM_NOWARNNOTFOUND|SYM_PLT,
symp->st_size, object);
if (this)
*gotp = this->st_value + ooff;
} else if (ELF32_ST_TYPE(symp->st_info) == STT_FUNC) {
*gotp += loff;
} else { /* XXX ??? */ /* Resolve all others immediatly */
*gotp = symp->st_value + loff;
}
gotp++;
symp++;
}
object->status |= STAT_GOT_DONE;
if (object->got_addr != NULL && object->got_size != 0)
_dl_mprotect((void*)object->got_addr, object->got_size,
PROT_READ);
if (object->plt_addr != NULL && object->plt_size != 0)
_dl_mprotect((void*)object->plt_addr, object->plt_size,
PROT_READ|PROT_EXEC);
}
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