NetBSD-5.0.2/libexec/ld.elf_so/arch/x86_64/mdreloc.c
/* $NetBSD: mdreloc.c,v 1.32 2008/07/24 04:39:26 matt Exp $ */
/*
* Copyright (c) 2001 Wasabi Systems, Inc.
* All rights reserved.
*
* Written by Frank van der Linden for Wasabi Systems, Inc.
*
* 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed for the NetBSD Project by
* Wasabi Systems, Inc.
* 4. The name of Wasabi Systems, Inc. may not be used to endorse
* or promote products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY WASABI SYSTEMS, INC. ``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 WASABI SYSTEMS, INC
* 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.
*/
/*
* Copyright 1996 John D. Polstra.
* Copyright 1996 Matt Thomas <matt@3am-software.com>
* 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. 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.
* 3. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by John Polstra.
* 4. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* 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.
*/
#include <sys/cdefs.h>
#ifndef lint
__RCSID("$NetBSD: mdreloc.c,v 1.32 2008/07/24 04:39:26 matt Exp $");
#endif /* not lint */
#include <sys/types.h>
#include <sys/mman.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <elf.h>
#include "debug.h"
#include "rtld.h"
void _rtld_bind_start(void);
void _rtld_relocate_nonplt_self(Elf_Dyn *, Elf_Addr);
caddr_t _rtld_bind(const Obj_Entry *, Elf_Word);
static inline int _rtld_relocate_plt_object(const Obj_Entry *,
const Elf_Rela *, Elf_Addr *);
void
_rtld_setup_pltgot(const Obj_Entry *obj)
{
obj->pltgot[1] = (Elf_Addr) obj;
obj->pltgot[2] = (Elf_Addr) &_rtld_bind_start;
}
void
_rtld_relocate_nonplt_self(Elf_Dyn *dynp, Elf_Addr relocbase)
{
const Elf_Rela *rela = 0, *relalim;
Elf_Addr relasz = 0;
Elf_Addr *where;
for (; dynp->d_tag != DT_NULL; dynp++) {
switch (dynp->d_tag) {
case DT_RELA:
rela = (const Elf_Rela *)(relocbase + dynp->d_un.d_ptr);
break;
case DT_RELASZ:
relasz = dynp->d_un.d_val;
break;
}
}
/*
* Assume only 64-bit relocations here, which should always
* be true for the dynamic linker.
*/
relalim = (const Elf_Rela *)((caddr_t)rela + relasz);
for (; rela < relalim; rela++) {
where = (Elf_Addr *)(relocbase + rela->r_offset);
*where = (Elf_Addr)(relocbase + rela->r_addend);
}
}
int
_rtld_relocate_nonplt_objects(const Obj_Entry *obj)
{
const Elf_Rela *rela;
const Elf_Sym *def = NULL;
const Obj_Entry *defobj =NULL;
for (rela = obj->rela; rela < obj->relalim; rela++) {
Elf64_Addr *where64;
Elf32_Addr *where32;
Elf64_Addr tmp64;
Elf32_Addr tmp32;
unsigned long symnum;
where64 = (Elf64_Addr *)(obj->relocbase + rela->r_offset);
where32 = (Elf32_Addr *)where64;
symnum = ELF_R_SYM(rela->r_info);
switch (ELF_R_TYPE(rela->r_info)) {
case R_TYPE(NONE):
break;
case R_TYPE(32): /* word32 S + A, truncate */
case R_TYPE(32S): /* word32 S + A, signed truncate */
case R_TYPE(GOT32): /* word32 G + A (XXX can we see these?) */
def = _rtld_find_symdef(symnum, obj, &defobj, false);
if (def == NULL)
return -1;
tmp32 = (Elf32_Addr)(u_long)(defobj->relocbase +
def->st_value + rela->r_addend);
if (*where32 != tmp32)
*where32 = tmp32;
rdbg(("32/32S %s in %s --> %p in %s",
obj->strtab + obj->symtab[symnum].st_name,
obj->path, (void *)(unsigned long)*where32,
defobj->path));
break;
case R_TYPE(64): /* word64 S + A */
def = _rtld_find_symdef(symnum, obj, &defobj, false);
if (def == NULL)
return -1;
tmp64 = (Elf64_Addr)(defobj->relocbase + def->st_value +
rela->r_addend);
if (*where64 != tmp64)
*where64 = tmp64;
rdbg(("64 %s in %s --> %p in %s",
obj->strtab + obj->symtab[symnum].st_name,
obj->path, (void *)*where64, defobj->path));
break;
case R_TYPE(PC32): /* word32 S + A - P */
def = _rtld_find_symdef(symnum, obj, &defobj, false);
if (def == NULL)
return -1;
tmp32 = (Elf32_Addr)(u_long)(defobj->relocbase +
def->st_value + rela->r_addend -
(Elf64_Addr)where64);
if (*where32 != tmp32)
*where32 = tmp32;
rdbg(("PC32 %s in %s --> %p in %s",
obj->strtab + obj->symtab[symnum].st_name,
obj->path, (void *)(unsigned long)*where32,
defobj->path));
break;
case R_TYPE(GLOB_DAT): /* word64 S */
def = _rtld_find_symdef(symnum, obj, &defobj, false);
if (def == NULL)
return -1;
tmp64 = (Elf64_Addr)(defobj->relocbase + def->st_value);
if (*where64 != tmp64)
*where64 = tmp64;
rdbg(("64 %s in %s --> %p in %s",
obj->strtab + obj->symtab[symnum].st_name,
obj->path, (void *)*where64, defobj->path));
break;
case R_TYPE(RELATIVE): /* word64 B + A */
tmp64 = (Elf64_Addr)(obj->relocbase + rela->r_addend);
if (*where64 != tmp64)
*where64 = tmp64;
rdbg(("RELATIVE in %s --> %p", obj->path,
(void *)*where64));
break;
case R_TYPE(COPY):
rdbg(("COPY"));
break;
default:
rdbg(("sym = %lu, type = %lu, offset = %p, "
"addend = %p, contents = %p, symbol = %s",
symnum, (u_long)ELF_R_TYPE(rela->r_info),
(void *)rela->r_offset, (void *)rela->r_addend,
(void *)*where64,
obj->strtab + obj->symtab[symnum].st_name));
_rtld_error("%s: Unsupported relocation type %ld "
"in non-PLT relocations\n",
obj->path, (u_long) ELF_R_TYPE(rela->r_info));
return -1;
}
}
return 0;
}
int
_rtld_relocate_plt_lazy(const Obj_Entry *obj)
{
const Elf_Rela *rela;
if (!obj->relocbase)
return 0;
for (rela = obj->pltrela; rela < obj->pltrelalim; rela++) {
Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JUMP_SLOT));
/* Just relocate the GOT slots pointing into the PLT */
*where += (Elf_Addr)obj->relocbase;
rdbg(("fixup !main in %s --> %p", obj->path, (void *)*where));
}
return 0;
}
static inline int
_rtld_relocate_plt_object(const Obj_Entry *obj, const Elf_Rela *rela, Elf_Addr *tp)
{
Elf_Addr *where = (Elf_Addr *)(obj->relocbase + rela->r_offset);
Elf_Addr new_value;
const Elf_Sym *def;
const Obj_Entry *defobj;
assert(ELF_R_TYPE(rela->r_info) == R_TYPE(JUMP_SLOT));
def = _rtld_find_symdef(ELF_R_SYM(rela->r_info), obj, &defobj, true);
if (def == NULL)
return -1;
new_value = (Elf_Addr)(defobj->relocbase + def->st_value +
rela->r_addend);
rdbg(("bind now/fixup in %s --> old=%p new=%p",
defobj->strtab + def->st_name, (void *)*where, (void *)new_value));
if (*where != new_value)
*where = new_value;
if (tp)
*tp = new_value - rela->r_addend;
return 0;
}
caddr_t
_rtld_bind(const Obj_Entry *obj, Elf_Word reloff)
{
const Elf_Rela *rela = obj->pltrela + reloff;
Elf_Addr new_value;
int err;
new_value = 0; /* XXX GCC4 */
err = _rtld_relocate_plt_object(obj, rela, &new_value);
if (err || new_value == 0)
_rtld_die();
return (caddr_t)new_value;
}
int
_rtld_relocate_plt_objects(const Obj_Entry *obj)
{
const Elf_Rela *rela;
for (rela = obj->pltrela; rela < obj->pltrelalim; rela++)
if (_rtld_relocate_plt_object(obj, rela, NULL) < 0)
return -1;
return 0;
}