/*-
* SPDX-License-Identifier: BSD-2-Clause-FreeBSD
*
* Copyright 1996-1998 John D. Polstra.
* 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 ``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>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/kernel.h>
#include <sys/systm.h>
#include <sys/exec.h>
#include <sys/imgact.h>
#include <sys/linker.h>
#include <sys/sysent.h>
#include <sys/imgact_elf.h>
#include <sys/proc.h>
#include <sys/syscall.h>
#include <sys/signalvar.h>
#include <sys/vnode.h>
#include <vm/vm.h>
#include <vm/pmap.h>
#include <vm/vm_param.h>
#include <machine/elf.h>
#include <machine/md_var.h>
#include <machine/stack.h>
#ifdef VFP
#include <machine/vfp.h>
#endif
#include "opt_ddb.h" /* for OPT_DDB */
#include "opt_global.h" /* for OPT_KDTRACE_HOOKS */
#include "opt_stack.h" /* for OPT_STACK */
static boolean_t elf32_arm_abi_supported(struct image_params *, int32_t *,
uint32_t *);
u_long elf_hwcap;
u_long elf_hwcap2;
struct sysentvec elf32_freebsd_sysvec = {
.sv_size = SYS_MAXSYSCALL,
.sv_table = sysent,
.sv_transtrap = NULL,
.sv_fixup = __elfN(freebsd_fixup),
.sv_sendsig = sendsig,
.sv_sigcode = sigcode,
.sv_szsigcode = &szsigcode,
.sv_name = "FreeBSD ELF32",
.sv_coredump = __elfN(coredump),
.sv_elf_core_osabi = ELFOSABI_FREEBSD,
.sv_elf_core_abi_vendor = FREEBSD_ABI_VENDOR,
.sv_elf_core_prepare_notes = __elfN(prepare_notes),
.sv_imgact_try = NULL,
.sv_minsigstksz = MINSIGSTKSZ,
.sv_minuser = VM_MIN_ADDRESS,
.sv_maxuser = VM_MAXUSER_ADDRESS,
.sv_usrstack = USRSTACK,
.sv_psstrings = PS_STRINGS,
.sv_stackprot = VM_PROT_ALL,
.sv_copyout_auxargs = __elfN(freebsd_copyout_auxargs),
.sv_copyout_strings = exec_copyout_strings,
.sv_setregs = exec_setregs,
.sv_fixlimit = NULL,
.sv_maxssiz = NULL,
.sv_flags =
SV_ASLR | SV_SHP | SV_TIMEKEEP | SV_RNG_SEED_VER |
SV_ABI_FREEBSD | SV_ILP32,
.sv_set_syscall_retval = cpu_set_syscall_retval,
.sv_fetch_syscall_args = cpu_fetch_syscall_args,
.sv_syscallnames = syscallnames,
.sv_shared_page_base = SHAREDPAGE,
.sv_shared_page_len = PAGE_SIZE,
.sv_schedtail = NULL,
.sv_thread_detach = NULL,
.sv_trap = NULL,
.sv_hwcap = &elf_hwcap,
.sv_hwcap2 = &elf_hwcap2,
};
INIT_SYSENTVEC(elf32_sysvec, &elf32_freebsd_sysvec);
static Elf32_Brandinfo freebsd_brand_info = {
.brand = ELFOSABI_FREEBSD,
.machine = EM_ARM,
.compat_3_brand = "FreeBSD",
.emul_path = NULL,
.interp_path = "/libexec/ld-elf.so.1",
.sysvec = &elf32_freebsd_sysvec,
.interp_newpath = NULL,
.brand_note = &elf32_freebsd_brandnote,
.flags = BI_CAN_EXEC_DYN | BI_BRAND_NOTE,
.header_supported= elf32_arm_abi_supported,
};
SYSINIT(elf32, SI_SUB_EXEC, SI_ORDER_FIRST,
(sysinit_cfunc_t) elf32_insert_brand_entry,
&freebsd_brand_info);
static boolean_t
elf32_arm_abi_supported(struct image_params *imgp, int32_t *osrel __unused,
uint32_t *fctl0 __unused)
{
const Elf_Ehdr *hdr = (const Elf_Ehdr *)imgp->image_header;
/*
* When configured for EABI, FreeBSD supports EABI vesions 4 and 5.
*/
if (EF_ARM_EABI_VERSION(hdr->e_flags) < EF_ARM_EABI_FREEBSD_MIN) {
if (bootverbose)
uprintf("Attempting to execute non EABI binary (rev %d) image %s",
EF_ARM_EABI_VERSION(hdr->e_flags), imgp->args->fname);
return (FALSE);
}
return (TRUE);
}
void
elf32_dump_thread(struct thread *td, void *dst, size_t *off)
{
#ifdef VFP
mcontext_vfp_t vfp;
if (dst != NULL) {
get_vfpcontext(td, &vfp);
*off = elf32_populate_note(NT_ARM_VFP, &vfp, dst, sizeof(vfp),
NULL);
} else
*off = elf32_populate_note(NT_ARM_VFP, NULL, NULL, sizeof(vfp),
NULL);
#endif
}
bool
elf_is_ifunc_reloc(Elf_Size r_info __unused)
{
return (false);
}
/*
* It is possible for the compiler to emit relocations for unaligned data.
* We handle this situation with these inlines.
*/
#define RELOC_ALIGNED_P(x) \
(((uintptr_t)(x) & (sizeof(void *) - 1)) == 0)
static __inline Elf_Addr
load_ptr(Elf_Addr *where)
{
Elf_Addr res;
if (RELOC_ALIGNED_P(where))
return *where;
memcpy(&res, where, sizeof(res));
return (res);
}
static __inline void
store_ptr(Elf_Addr *where, Elf_Addr val)
{
if (RELOC_ALIGNED_P(where))
*where = val;
else
memcpy(where, &val, sizeof(val));
}
#undef RELOC_ALIGNED_P
/* Process one elf relocation with addend. */
static int
elf_reloc_internal(linker_file_t lf, Elf_Addr relocbase, const void *data,
int type, int local, elf_lookup_fn lookup)
{
Elf_Addr *where;
Elf_Addr addr;
Elf_Addr addend;
Elf_Word rtype, symidx;
const Elf_Rel *rel;
const Elf_Rela *rela;
int error;
switch (type) {
case ELF_RELOC_REL:
rel = (const Elf_Rel *)data;
where = (Elf_Addr *) (relocbase + rel->r_offset);
addend = load_ptr(where);
rtype = ELF_R_TYPE(rel->r_info);
symidx = ELF_R_SYM(rel->r_info);
break;
case ELF_RELOC_RELA:
rela = (const Elf_Rela *)data;
where = (Elf_Addr *) (relocbase + rela->r_offset);
addend = rela->r_addend;
rtype = ELF_R_TYPE(rela->r_info);
symidx = ELF_R_SYM(rela->r_info);
break;
default:
panic("unknown reloc type %d\n", type);
}
if (local) {
if (rtype == R_ARM_RELATIVE) { /* A + B */
addr = elf_relocaddr(lf, relocbase + addend);
if (load_ptr(where) != addr)
store_ptr(where, addr);
}
return (0);
}
switch (rtype) {
case R_ARM_NONE: /* none */
break;
case R_ARM_ABS32:
error = lookup(lf, symidx, 1, &addr);
if (error != 0)
return (-1);
store_ptr(where, addr + load_ptr(where));
break;
case R_ARM_COPY: /* none */
/*
* There shouldn't be copy relocations in kernel
* objects.
*/
printf("kldload: unexpected R_COPY relocation, "
"symbol index %d\n", symidx);
return (-1);
break;
case R_ARM_JUMP_SLOT:
error = lookup(lf, symidx, 1, &addr);
if (error == 0) {
store_ptr(where, addr);
return (0);
}
return (-1);
case R_ARM_RELATIVE:
break;
default:
printf("kldload: unexpected relocation type %d, "
"symbol index %d\n", rtype, symidx);
return (-1);
}
return(0);
}
int
elf_reloc(linker_file_t lf, Elf_Addr relocbase, const void *data, int type,
elf_lookup_fn lookup)
{
return (elf_reloc_internal(lf, relocbase, data, type, 0, lookup));
}
int
elf_reloc_local(linker_file_t lf, Elf_Addr relocbase, const void *data,
int type, elf_lookup_fn lookup)
{
return (elf_reloc_internal(lf, relocbase, data, type, 1, lookup));
}
int
elf_cpu_load_file(linker_file_t lf)
{
/*
* The pmap code does not do an icache sync upon establishing executable
* mappings in the kernel pmap. It's an optimization based on the fact
* that kernel memory allocations always have EXECUTABLE protection even
* when the memory isn't going to hold executable code. The only time
* kernel memory holding instructions does need a sync is after loading
* a kernel module, and that's when this function gets called.
*
* This syncs data and instruction caches after loading a module. We
* don't worry about the kernel itself (lf->id is 1) as locore.S did
* that on entry. Even if data cache maintenance was done by IO code,
* the relocation fixup process creates dirty cache entries that we must
* write back before doing icache sync. The instruction cache sync also
* invalidates the branch predictor cache on platforms that have one.
*/
if (lf->id == 1)
return (0);
dcache_wb_pou((vm_offset_t)lf->address, (vm_size_t)lf->size);
icache_inv_all();
#if defined(DDB) || defined(KDTRACE_HOOKS) || defined(STACK)
/*
* Inform the stack(9) code of the new module, so it can acquire its
* per-module unwind data.
*/
unwind_module_loaded(lf);
#endif
return (0);
}
int
elf_cpu_parse_dynamic(caddr_t loadbase __unused, Elf_Dyn *dynamic __unused)
{
return (0);
}
int
elf_cpu_unload_file(linker_file_t lf)
{
#if defined(DDB) || defined(KDTRACE_HOOKS) || defined(STACK)
/* Inform the stack(9) code that this module is gone. */
unwind_module_unloaded(lf);
#endif
return (0);
}
