/*-
* Copyright (c) 2008, Juniper Networks, Inc.
* 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. Neither the name of the author nor the names of any co-contributors
* may 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>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/endian.h>
#include <sys/kerneldump.h>
#include <sys/mman.h>
#include <vm/vm.h>
#include <db.h>
#include <elf.h>
#include <limits.h>
#include <kvm.h>
#include <stdlib.h>
#include <string.h>
#include "kvm_private.h"
struct vmstate {
void *map;
size_t mapsz;
size_t dmphdrsz;
Elf32_Ehdr *eh;
Elf32_Phdr *ph;
};
static int
valid_elf_header(Elf32_Ehdr *eh)
{
if (!IS_ELF(*eh))
return (0);
if (eh->e_ident[EI_CLASS] != ELFCLASS32)
return (0);
if (eh->e_ident[EI_DATA] != ELFDATA2MSB)
return (0);
if (eh->e_ident[EI_VERSION] != EV_CURRENT)
return (0);
if (eh->e_ident[EI_OSABI] != ELFOSABI_STANDALONE)
return (0);
if (be16toh(eh->e_type) != ET_CORE)
return (0);
if (be16toh(eh->e_machine) != EM_PPC)
return (0);
/* Can't think of anything else to check... */
return (1);
}
static size_t
dump_header_size(struct kerneldumpheader *dh)
{
if (strcmp(dh->magic, KERNELDUMPMAGIC) != 0)
return (0);
if (strcmp(dh->architecture, "powerpc") != 0)
return (0);
/* That should do it... */
return (sizeof(*dh));
}
/*
* Map the ELF headers into the process' address space. We do this in two
* steps: first the ELF header itself and using that information the whole
* set of headers.
*/
static int
powerpc_maphdrs(kvm_t *kd)
{
struct vmstate *vm;
size_t mapsz;
vm = kd->vmst;
vm->mapsz = PAGE_SIZE;
vm->map = mmap(NULL, vm->mapsz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0);
if (vm->map == MAP_FAILED) {
_kvm_err(kd, kd->program, "cannot map corefile");
return (-1);
}
vm->dmphdrsz = 0;
vm->eh = vm->map;
if (!valid_elf_header(vm->eh)) {
/*
* Hmmm, no ELF header. Maybe we still have a dump header.
* This is normal when the core file wasn't created by
* savecore(8), but instead was dumped over TFTP. We can
* easily skip the dump header...
*/
vm->dmphdrsz = dump_header_size(vm->map);
if (vm->dmphdrsz == 0)
goto inval;
vm->eh = (void *)((uintptr_t)vm->map + vm->dmphdrsz);
if (!valid_elf_header(vm->eh))
goto inval;
}
mapsz = be16toh(vm->eh->e_phentsize) * be16toh(vm->eh->e_phnum) +
be32toh(vm->eh->e_phoff);
munmap(vm->map, vm->mapsz);
/* Map all headers. */
vm->mapsz = vm->dmphdrsz + mapsz;
vm->map = mmap(NULL, vm->mapsz, PROT_READ, MAP_PRIVATE, kd->pmfd, 0);
if (vm->map == MAP_FAILED) {
_kvm_err(kd, kd->program, "cannot map corefle headers");
return (-1);
}
vm->eh = (void *)((uintptr_t)vm->map + vm->dmphdrsz);
vm->ph = (void *)((uintptr_t)vm->eh + be32toh(vm->eh->e_phoff));
return (0);
inval:
munmap(vm->map, vm->mapsz);
vm->map = MAP_FAILED;
_kvm_err(kd, kd->program, "invalid corefile");
return (-1);
}
/*
* Determine the offset within the corefile corresponding the virtual
* address. Return the number of contiguous bytes in the corefile or
* 0 when the virtual address is invalid.
*/
static size_t
powerpc_va2off(kvm_t *kd, u_long va, off_t *ofs)
{
struct vmstate *vm = kd->vmst;
Elf32_Phdr *ph;
int nph;
ph = vm->ph;
nph = be16toh(vm->eh->e_phnum);
while (nph && (va < be32toh(ph->p_vaddr) ||
va >= be32toh(ph->p_vaddr) + be32toh(ph->p_memsz))) {
nph--;
ph = (void *)((uintptr_t)ph + be16toh(vm->eh->e_phentsize));
}
if (nph == 0)
return (0);
/* Segment found. Return file offset and range. */
*ofs = vm->dmphdrsz + be32toh(ph->p_offset) +
(va - be32toh(ph->p_vaddr));
return (be32toh(ph->p_memsz) - (va - be32toh(ph->p_vaddr)));
}
void
_kvm_freevtop(kvm_t *kd)
{
struct vmstate *vm = kd->vmst;
if (vm == NULL)
return;
if (vm->eh != MAP_FAILED) {
munmap(vm->eh, vm->mapsz);
vm->eh = MAP_FAILED;
}
free(vm);
kd->vmst = NULL;
}
int
_kvm_initvtop(kvm_t *kd)
{
kd->vmst = (struct vmstate *)_kvm_malloc(kd, sizeof(*kd->vmst));
if (kd->vmst == NULL) {
_kvm_err(kd, kd->program, "out of virtual memory");
return (-1);
}
if (powerpc_maphdrs(kd) == -1) {
free(kd->vmst);
kd->vmst = NULL;
return (-1);
}
return (0);
}
int
_kvm_kvatop(kvm_t *kd, u_long va, off_t *ofs)
{
struct vmstate *vm;
vm = kd->vmst;
if (vm->ph->p_paddr == ~0U)
return ((int)powerpc_va2off(kd, va, ofs));
_kvm_err(kd, kd->program, "Raw corefile not supported");
return (0);
}
