HardenedBSD/stand/common/reloc_elf.c
John Baldwin 4a3cf5f329 Stop #defining FREEBSD_ELF
This was originally used (along with FREEBSD_AOUT) to prefer the use
of ELF in various tools instead of a.out as part of the a.out to ELF
transition in the 3.x days.  The last use of it was removed from
<link.h> in commit 66422f5b7a back in
2002, but various files still #define it.

Reviewed by:	kevans, imp, emaste
Sponsored by:	DARPA
Differential Revision:	https://reviews.freebsd.org/D42964
2023-12-12 15:30:00 -08:00

225 lines
6.1 KiB
C

/*-
* Copyright (c) 2003 Jake Burkholder.
* Copyright 1996-1998 John D. Polstra.
* Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
* Copyright (c) 1998 Peter Wemm <peter@freebsd.org>
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND 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 AUTHOR OR 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.
*/
#include <sys/types.h>
#include <machine/elf.h>
#include <stand.h>
#include <sys/link_elf.h>
#include "bootstrap.h"
#define COPYOUT(s,d,l) archsw.arch_copyout((vm_offset_t)(s), d, l)
/*
* Apply a single intra-module relocation to the data. `relbase' is the
* target relocation base for the section (i.e. it corresponds to where
* r_offset == 0). `dataaddr' is the relocated address corresponding to
* the start of the data, and `len' is the number of bytes.
*/
int
__elfN(reloc)(struct elf_file *ef, symaddr_fn *symaddr, const void *reldata,
int reltype, Elf_Addr relbase, Elf_Addr dataaddr, void *data, size_t len)
{
#if (defined(__aarch64__) || defined(__amd64__) || defined(__i386__)) && \
__ELF_WORD_SIZE == 64
Elf64_Addr *where, val;
Elf_Addr addend, addr;
Elf_Size rtype;
#if defined(__amd64__) || defined(__i386__)
Elf_Size symidx;
#endif
const Elf_Rel *rel;
const Elf_Rela *rela;
switch (reltype) {
case ELF_RELOC_REL:
rel = (const Elf_Rel *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rel->r_offset -
dataaddr);
addend = 0;
rtype = ELF_R_TYPE(rel->r_info);
#if defined(__amd64__) || defined(__i386__)
symidx = ELF_R_SYM(rel->r_info);
#endif
addend = 0;
break;
case ELF_RELOC_RELA:
rela = (const Elf_Rela *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rela->r_offset -
dataaddr);
addend = rela->r_addend;
rtype = ELF_R_TYPE(rela->r_info);
#if defined(__amd64__) || defined(__i386__)
symidx = ELF_R_SYM(rela->r_info);
#endif
break;
default:
return (EINVAL);
}
if ((char *)where < (char *)data || (char *)where >= (char *)data + len)
return (0);
if (reltype == ELF_RELOC_REL)
addend = *where;
#if defined(__aarch64__)
#define RELOC_RELATIVE R_AARCH64_RELATIVE
#define RELOC_IRELATIVE R_AARCH64_IRELATIVE
#elif defined(__amd64__) || defined(__i386__)
/* XXX, definitions not available on i386. */
#define R_X86_64_64 1
#define R_X86_64_RELATIVE 8
#define R_X86_64_IRELATIVE 37
#define RELOC_RELATIVE R_X86_64_RELATIVE
#define RELOC_IRELATIVE R_X86_64_IRELATIVE
#endif
switch (rtype) {
case RELOC_RELATIVE:
addr = (Elf_Addr)addend + relbase;
val = addr;
memcpy(where, &val, sizeof(val));
break;
case RELOC_IRELATIVE:
/* leave it to kernel */
break;
#if defined(__amd64__) || defined(__i386__)
case R_X86_64_64: /* S + A */
addr = symaddr(ef, symidx);
if (addr == 0)
return (ESRCH);
val = addr + addend;
*where = val;
break;
#endif
default:
printf("\nunhandled relocation type %u\n", (u_int)rtype);
return (EFTYPE);
}
return (0);
#elif defined(__i386__) && __ELF_WORD_SIZE == 32
Elf_Addr addend, addr, *where, val;
Elf_Size rtype, symidx;
const Elf_Rel *rel;
const Elf_Rela *rela;
switch (reltype) {
case ELF_RELOC_REL:
rel = (const Elf_Rel *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rel->r_offset -
dataaddr);
addend = 0;
rtype = ELF_R_TYPE(rel->r_info);
symidx = ELF_R_SYM(rel->r_info);
addend = 0;
break;
case ELF_RELOC_RELA:
rela = (const Elf_Rela *)reldata;
where = (Elf_Addr *)((char *)data + relbase + rela->r_offset -
dataaddr);
addend = rela->r_addend;
rtype = ELF_R_TYPE(rela->r_info);
symidx = ELF_R_SYM(rela->r_info);
break;
default:
return (EINVAL);
}
if ((char *)where < (char *)data || (char *)where >= (char *)data + len)
return (0);
if (reltype == ELF_RELOC_REL)
addend = *where;
/* XXX, definitions not available on amd64. */
#define R_386_32 1 /* Add symbol value. */
#define R_386_GLOB_DAT 6 /* Set GOT entry to data address. */
#define R_386_RELATIVE 8 /* Add load address of shared object. */
#define R_386_IRELATIVE 42
switch (rtype) {
case R_386_RELATIVE:
addr = addend + relbase;
*where = addr;
break;
case R_386_32: /* S + A */
addr = symaddr(ef, symidx);
if (addr == 0)
return (ESRCH);
val = addr + addend;
*where = val;
break;
case R_386_IRELATIVE:
/* leave it to kernel */
break;
default:
printf("\nunhandled relocation type %u\n", (u_int)rtype);
return (EFTYPE);
}
return (0);
#elif defined(__powerpc__) || defined(__riscv)
Elf_Size w;
const Elf_Rela *rela;
switch (reltype) {
case ELF_RELOC_RELA:
rela = reldata;
if (relbase + rela->r_offset >= dataaddr &&
relbase + rela->r_offset < dataaddr + len) {
switch (ELF_R_TYPE(rela->r_info)) {
#if defined(__powerpc__)
case R_PPC_RELATIVE:
#elif defined(__riscv)
case R_RISCV_RELATIVE:
#endif
w = relbase + rela->r_addend;
bcopy(&w, (u_char *)data + (relbase +
rela->r_offset - dataaddr), sizeof(w));
break;
default:
printf("\nunhandled relocation type %u\n",
(u_int)ELF_R_TYPE(rela->r_info));
return (EFTYPE);
}
}
break;
}
return (0);
#else
return (EOPNOTSUPP);
#endif
}