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QEMU-Nyx-fork/nyx/memory_access.c

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/*
Copyright (C) 2017 Sergej Schumilo
This file is part of QEMU-PT (kAFL).
QEMU-PT is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 2 of the License, or
(at your option) any later version.
QEMU-PT is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with QEMU-PT. If not, see <http://www.gnu.org/licenses/>.
*/
#include <errno.h>
#include "qemu/osdep.h"
#include "sysemu/sysemu.h"
#include "cpu.h"
#include "exec/ram_addr.h"
#include "qemu/rcu_queue.h"
#include "memory_access.h"
#include "nyx/hypercall/hypercall.h"
#include "debug.h"
#include "nyx/fast_vm_reload.h"
#include "exec/gdbstub.h"
#include "nyx/state/state.h"
#include "sysemu/kvm.h"
#include "nyx/helpers.h"
#define INVALID_ADDRESS 0xFFFFFFFFFFFFFFFFULL
static uint64_t get_48_paging_phys_addr(uint64_t cr3, uint64_t addr, bool read_from_snapshot);
#define x86_64_PAGE_SIZE 0x1000
#define x86_64_PAGE_MASK ~(x86_64_PAGE_SIZE - 1)
static void set_mem_mode(CPUState *cpu){
kvm_arch_get_registers(cpu);
X86CPU *cpux86 = X86_CPU(cpu);
CPUX86State *env = &cpux86->env;
if (!(env->cr[0] & CR0_PG_MASK)) {
GET_GLOBAL_STATE()->mem_mode = mm_32_protected;
return;
}
else{
if (env->cr[4] & CR4_PAE_MASK) {
if (env->hflags & HF_LMA_MASK) {
if (env->cr[4] & CR4_LA57_MASK) {
GET_GLOBAL_STATE()->mem_mode = mm_64_l5_paging;
return;
} else {
GET_GLOBAL_STATE()->mem_mode = mm_64_l4_paging;
return;
}
}
else{
GET_GLOBAL_STATE()->mem_mode = mm_32_pae;
return;
}
}
else {
GET_GLOBAL_STATE()->mem_mode = mm_32_paging;
return;
}
}
return;
}
/* Warning: This might break memory handling for hypervisor fuzzing => FIXME LATER */
uint64_t get_paging_phys_addr(CPUState *cpu, uint64_t cr3, uint64_t addr){
if(GET_GLOBAL_STATE()->mem_mode == mm_unkown){
set_mem_mode(cpu);
}
switch(GET_GLOBAL_STATE()->mem_mode){
case mm_32_protected:
return addr & 0xFFFFFFFFULL;
case mm_32_paging:
fprintf(stderr, "mem_mode: mm_32_paging not implemented!\n");
abort();
case mm_32_pae:
fprintf(stderr, "mem_mode: mm_32_pae not implemented!\n");
abort();
case mm_64_l4_paging:
return get_48_paging_phys_addr(cr3, addr, false);
case mm_64_l5_paging:
fprintf(stderr, "mem_mode: mm_64_l5_paging not implemented!\n");
abort();
case mm_unkown:
fprintf(stderr, "mem_mode: unkown!\n");
abort();
}
return 0;
}
static uint64_t get_paging_phys_addr_snapshot(CPUState *cpu, uint64_t cr3, uint64_t addr){
if(GET_GLOBAL_STATE()->mem_mode == mm_unkown){
set_mem_mode(cpu);
}
switch(GET_GLOBAL_STATE()->mem_mode){
case mm_32_protected:
return addr & 0xFFFFFFFFULL;
case mm_32_paging:
fprintf(stderr, "mem_mode: mm_32_paging not implemented!\n");
abort();
case mm_32_pae:
fprintf(stderr, "mem_mode: mm_32_pae not implemented!\n");
abort();
case mm_64_l4_paging:
return get_48_paging_phys_addr(cr3, addr, true);
case mm_64_l5_paging:
fprintf(stderr, "mem_mode: mm_64_l5_paging not implemented!\n");
abort();
case mm_unkown:
fprintf(stderr, "mem_mode: unkown!\n");
abort();
}
return 0;
}
bool read_physical_memory(uint64_t address, uint8_t* data, uint32_t size, CPUState *cpu){
kvm_arch_get_registers(cpu);
cpu_physical_memory_read(address, data, size);
return true;
}
bool write_physical_memory(uint64_t address, uint8_t* data, uint32_t size, CPUState *cpu){
kvm_arch_get_registers(cpu);
cpu_physical_memory_write(address, data, size);
return true;
}
static void refresh_kvm(CPUState *cpu){
//int ret = 0;
if (!cpu->vcpu_dirty) {
//kvm_arch_get_registers_fast(cpu);
kvm_arch_get_registers(cpu);
//cpu->vcpu_dirty = true;
}
}
static void refresh_kvm_non_dirty(CPUState *cpu){
if (!cpu->vcpu_dirty) {
kvm_arch_get_registers_fast(cpu);
//kvm_arch_get_registers(cpu);
}
}
bool remap_payload_slot(uint64_t phys_addr, uint32_t slot, CPUState *cpu){
//assert(0); /* nested code -> test me later */
assert(GET_GLOBAL_STATE()->shared_payload_buffer_fd && GET_GLOBAL_STATE()->shared_payload_buffer_size);
RAMBlock *block;
refresh_kvm_non_dirty(cpu);
uint32_t i = slot;
uint64_t phys_addr_ram_offset = address_to_ram_offset(phys_addr);
QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if(!memcmp(block->idstr, "pc.ram", 6)){
/* TODO: put assert calls here */
munmap((void*)(((uint64_t)block->host) + phys_addr_ram_offset), x86_64_PAGE_SIZE);
mmap((void*)(((uint64_t)block->host) + phys_addr_ram_offset), 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_FIXED, GET_GLOBAL_STATE()->shared_payload_buffer_fd, (i*x86_64_PAGE_SIZE));
//printf("MMUNMAP: %d\n", munmap((void*)(((uint64_t)block->host) + phys_addr), x86_64_PAGE_SIZE));
//printf("MMAP: %p\n", mmap((void*)(((uint64_t)block->host) + phys_addr), 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_FIXED, GET_GLOBAL_STATE()->shared_payload_buffer_fd, (i*x86_64_PAGE_SIZE)));
fast_reload_blacklist_page(get_fast_reload_snapshot(), phys_addr);
break;
}
}
return true;
}
bool remap_slot(uint64_t addr, uint32_t slot, CPUState *cpu, int fd, uint64_t shm_size, bool virtual, uint64_t cr3){
//printf("%s ---> \n", __func__);
assert(fd && shm_size);
assert((slot*x86_64_PAGE_SIZE) < shm_size);
RAMBlock *block;
refresh_kvm_non_dirty(cpu);
uint32_t i = slot;
uint64_t phys_addr = addr;
if(virtual){
phys_addr = get_paging_phys_addr(cpu, cr3, (addr & x86_64_PAGE_MASK));
if(phys_addr == INVALID_ADDRESS){
fprintf(stderr, "[QEMU-Nyx] Error: failed to translate v_addr (0x%lx) to p_addr!\n", addr);
fprintf(stderr, "[QEMU-Nyx] Check if the buffer is present in the guest's memory...\n");
exit(1);
}
}
uint64_t phys_addr_ram_offset = address_to_ram_offset(phys_addr);
//printf("phys_addr -> %lx\n", phys_addr);
debug_fprintf(stderr, "%s: addr => %lx phys_addr => %lx\n", __func__, addr, phys_addr);
QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if(!memcmp(block->idstr, "pc.ram", 6)){
/* TODO: put assert calls here */
if (munmap((void*)(((uint64_t)block->host) + phys_addr_ram_offset), x86_64_PAGE_SIZE) == -1) {
fprintf(stderr, "%s: munmap failed!\n", __func__);
assert(false);
}
if (mmap((void*)(((uint64_t)block->host) + phys_addr_ram_offset), 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_FIXED, fd, (i*x86_64_PAGE_SIZE)) == MAP_FAILED) {
fprintf(stderr, "%s: mmap failed!\n", __func__);
assert(false);
}
//printf("MMUNMAP: %d\n", munmap((void*)(((uint64_t)block->host) + phys_addr), x86_64_PAGE_SIZE));
//printf("MMAP: %p\n", mmap((void*)(((uint64_t)block->host) + phys_addr), 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_FIXED, fd, (i*x86_64_PAGE_SIZE)));
fast_reload_blacklist_page(get_fast_reload_snapshot(), phys_addr);
break;
}
}
return true;
}
bool remap_payload_slot_protected(uint64_t phys_addr, uint32_t slot, CPUState *cpu){
//assert(0); /* nested code -> test me later */
assert(GET_GLOBAL_STATE()->shared_payload_buffer_fd && GET_GLOBAL_STATE()->shared_payload_buffer_size);
RAMBlock *block;
refresh_kvm_non_dirty(cpu);
uint32_t i = slot;
uint64_t phys_addr_ram_offset = address_to_ram_offset(phys_addr);
QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if(!memcmp(block->idstr, "pc.ram", 6)){
/* TODO: put assert calls here */
munmap((void*)(((uint64_t)block->host) + phys_addr_ram_offset), x86_64_PAGE_SIZE);
mmap((void*)(((uint64_t)block->host) + phys_addr_ram_offset), 0x1000, PROT_READ , MAP_SHARED | MAP_FIXED, GET_GLOBAL_STATE()->shared_payload_buffer_fd, (i*x86_64_PAGE_SIZE));
//printf("MMUNMAP: %d\n", munmap((void*)(((uint64_t)block->host) + phys_addr), x86_64_PAGE_SIZE));
//printf("MMAP: %p\n", mmap((void*)(((uint64_t)block->host) + phys_addr), 0x1000, PROT_READ , MAP_SHARED | MAP_FIXED, GET_GLOBAL_STATE()->shared_payload_buffer_fd, (i*x86_64_PAGE_SIZE)));
fast_reload_blacklist_page(get_fast_reload_snapshot(), phys_addr);
break;
}
}
return true;
}
void resize_shared_memory(uint32_t new_size, uint32_t* shm_size, void** shm_ptr, int fd){
assert(fd && *shm_size);
/* check if the new_size is a multiple of PAGE_SIZE */
if(new_size & (PAGE_SIZE-1)){
new_size = (new_size & ~(PAGE_SIZE-1)) + PAGE_SIZE;
}
if(*shm_size >= new_size){
/* no need no resize the buffer -> early exit */
return;
}
assert(!GET_GLOBAL_STATE()->in_fuzzing_mode);
assert(ftruncate(fd, new_size) == 0);
if(shm_ptr){
munmap(*shm_ptr , *shm_size);
*shm_ptr = (void*)mmap(0, new_size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
assert(*shm_ptr != MAP_FAILED);
}
*shm_size = new_size;
}
bool remap_payload_buffer(uint64_t virt_guest_addr, CPUState *cpu){
assert(GET_GLOBAL_STATE()->shared_payload_buffer_fd && GET_GLOBAL_STATE()->shared_payload_buffer_size);
assert(GET_GLOBAL_STATE()->shared_payload_buffer_size % x86_64_PAGE_SIZE == 0);
RAMBlock *block;
refresh_kvm_non_dirty(cpu);
for(uint32_t i = 0; i < (GET_GLOBAL_STATE()->shared_payload_buffer_size/x86_64_PAGE_SIZE); i++){
//MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED;
//hwaddr phys_addr = cpu_get_phys_page_attrs_debug(cpu, ((virt_guest_addr+(i*x86_64_PAGE_SIZE)) & x86_64_PAGE_MASK), &attrs);
uint64_t phys_addr = get_paging_phys_addr(cpu, GET_GLOBAL_STATE()->parent_cr3, ((virt_guest_addr+(i*x86_64_PAGE_SIZE)) & x86_64_PAGE_MASK));
assert(phys_addr != INVALID_ADDRESS);
uint64_t phys_addr_ram_offset = address_to_ram_offset(phys_addr);
QLIST_FOREACH_RCU(block, &ram_list.blocks, next) {
if(!memcmp(block->idstr, "pc.ram", 6)){
//printf("MMUNMAP: %d\n", munmap((void*)(((uint64_t)block->host) + phys_addr), x86_64_PAGE_SIZE));
if(munmap((void*)(((uint64_t)block->host) + phys_addr_ram_offset), x86_64_PAGE_SIZE) == -1){
fprintf(stderr, "munmap failed!\n");
//exit(1);
assert(false);
}
//printf("MMAP: %lx\n", mmap((void*)(((uint64_t)block->host) + phys_addr), 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_FIXED, shared_payload_buffer_fd, (i*x86_64_PAGE_SIZE)));
if(mmap((void*)(((uint64_t)block->host) + phys_addr_ram_offset), 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_FIXED, GET_GLOBAL_STATE()->shared_payload_buffer_fd, (i*x86_64_PAGE_SIZE)) == MAP_FAILED){
fprintf(stderr, "mmap failed!\n");
//exit(1);
assert(false);
}
memset((block->host) + phys_addr_ram_offset, 0xab, 0x1000);
if(GET_GLOBAL_STATE()->protect_payload_buffer){
mprotect((block->host) + phys_addr_ram_offset, 0x1000, PROT_READ);
}
fast_reload_blacklist_page(get_fast_reload_snapshot(), phys_addr);
break;
}
}
}
return true;
}
bool write_virtual_memory(uint64_t address, uint8_t* data, uint32_t size, CPUState *cpu)
{
/* Todo: later &address_space_memory + phys_addr -> mmap SHARED */
int asidx;
MemTxAttrs attrs;
hwaddr phys_addr;
MemTxResult res;
uint64_t counter, l, i;
counter = size;
while(counter != 0){
l = x86_64_PAGE_SIZE;
if (l > counter)
l = counter;
refresh_kvm(cpu);
//cpu_synchronize_state(cpu);
asidx = cpu_asidx_from_attrs(cpu, MEMTXATTRS_UNSPECIFIED);
attrs = MEMTXATTRS_UNSPECIFIED;
phys_addr = cpu_get_phys_page_attrs_debug(cpu, (address & x86_64_PAGE_MASK), &attrs);
if (phys_addr == INVALID_ADDRESS){
QEMU_PT_PRINTF(MEM_PREFIX, "phys_addr == -1:\t%lx", address);
return false;
}
phys_addr += (address & ~x86_64_PAGE_MASK);
res = address_space_rw(cpu_get_address_space(cpu, asidx), phys_addr, MEMTXATTRS_UNSPECIFIED, data, l, true);
if (res != MEMTX_OK){
QEMU_PT_PRINTF(MEM_PREFIX, "!MEMTX_OK:\t%lx", address);
return false;
}
i++;
data += l;
address += l;
counter -= l;
}
return true;
}
void hexdump_virtual_memory(uint64_t address, uint32_t size, CPUState *cpu){
assert(size < 0x100000); // 1MB max
uint64_t i = 0;
uint8_t tmp[17];
uint8_t* data = malloc(size);
bool success = read_virtual_memory(address, data, size, cpu);
if(success){
for (i = 0; i < size; i++){
if(!(i % 16)){
if (i != 0){
printf (" %s\n", tmp);
}
printf (" %04lx ", i);
}
printf (" %02x", data[i]);
if ((data[i] < 0x20) || (data[i] > 0x7e))
tmp[i % 16] = '.';
else
tmp[i % 16] = data[i];
tmp[(i % 16) + 1] = '\0';
}
while ((i % 16) != 0) {
printf (" ");
i++;
}
printf (" %s\n", tmp);
}
free(data);
}
static int redqueen_insert_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp)
{
static const uint8_t int3 = 0xcc;
hwaddr phys_addr = (hwaddr) get_paging_phys_addr(cs, GET_GLOBAL_STATE()->parent_cr3, bp->pc);
int asidx = cpu_asidx_from_attrs(cs, MEMTXATTRS_UNSPECIFIED);
if (address_space_rw(cpu_get_address_space(cs, asidx), phys_addr, MEMTXATTRS_UNSPECIFIED, (uint8_t *)&bp->saved_insn, 1, 0) ||
address_space_rw(cpu_get_address_space(cs, asidx), phys_addr, MEMTXATTRS_UNSPECIFIED, (uint8_t *)&int3, 1, 1)) {
//fprintf(stderr, "%s WRITTE AT %lx %lx failed!\n", __func__, bp->pc, phys_addr);
return -EINVAL;
}
return 0;
}
static int redqueen_remove_sw_breakpoint(CPUState *cs, struct kvm_sw_breakpoint *bp)
{
uint8_t int3;
hwaddr phys_addr = (hwaddr) get_paging_phys_addr(cs, GET_GLOBAL_STATE()->parent_cr3, bp->pc);
int asidx = cpu_asidx_from_attrs(cs, MEMTXATTRS_UNSPECIFIED);
if (address_space_rw(cpu_get_address_space(cs, asidx), phys_addr, MEMTXATTRS_UNSPECIFIED, (uint8_t *)&int3, 1, 0) || int3 != 0xcc ||
address_space_rw(cpu_get_address_space(cs, asidx), phys_addr, MEMTXATTRS_UNSPECIFIED, (uint8_t *)&bp->saved_insn, 1, 1)) {
//fprintf(stderr, "%s failed\n", __func__);
return -EINVAL;
}
return 0;
}
static struct kvm_sw_breakpoint *redqueen_find_breakpoint(CPUState *cpu, target_ulong pc){
struct kvm_sw_breakpoint *bp;
QTAILQ_FOREACH(bp, &GET_GLOBAL_STATE()->redqueen_breakpoints, entry) {
if (bp->pc == pc) {
return bp;
}
}
return NULL;
}
static int redqueen_breakpoints_active(CPUState *cpu){
return !QTAILQ_EMPTY(&GET_GLOBAL_STATE()->redqueen_breakpoints);
}
struct kvm_set_guest_debug_data {
struct kvm_guest_debug dbg;
int err;
};
static int redqueen_update_guest_debug(CPUState *cpu) {
struct kvm_set_guest_debug_data data;
data.dbg.control = 0;
if (redqueen_breakpoints_active(cpu)) {
data.dbg.control |= KVM_GUESTDBG_ENABLE | KVM_GUESTDBG_USE_SW_BP;
}
return kvm_vcpu_ioctl(cpu, KVM_SET_GUEST_DEBUG, &data.dbg);
return 0;
}
static void redqueen_remove_all_breakpoints(CPUState *cpu) {
struct kvm_sw_breakpoint *bp, *next;
QTAILQ_FOREACH_SAFE(bp, &GET_GLOBAL_STATE()->redqueen_breakpoints, entry, next) {
redqueen_remove_sw_breakpoint(cpu, bp);
QTAILQ_REMOVE(&GET_GLOBAL_STATE()->redqueen_breakpoints, bp, entry);
g_free(bp);
}
redqueen_update_guest_debug(cpu);
}
static int redqueen_insert_breakpoint(CPUState *cpu, target_ulong addr, target_ulong len){
struct kvm_sw_breakpoint *bp;
int err;
bp = redqueen_find_breakpoint(cpu, addr);
if (bp) {
bp->use_count++;
return 0;
}
bp = g_malloc(sizeof(struct kvm_sw_breakpoint));
bp->pc = addr;
bp->use_count = 1;
err = redqueen_insert_sw_breakpoint(cpu, bp);
if (err) {
g_free(bp);
return err;
}
QTAILQ_INSERT_HEAD(&GET_GLOBAL_STATE()->redqueen_breakpoints, bp, entry);
err = redqueen_update_guest_debug(cpu);
if(err){
return err;
}
return 0;
}
static int redqueen_remove_breakpoint(CPUState *cpu, target_ulong addr, target_ulong len){
struct kvm_sw_breakpoint *bp;
int err;
bp = redqueen_find_breakpoint(cpu, addr);
if (!bp) {
return -ENOENT;
}
if (bp->use_count > 1) {
bp->use_count--;
return 0;
}
err = redqueen_remove_sw_breakpoint(cpu, bp);
if (err) {
return err;
}
QTAILQ_REMOVE(&GET_GLOBAL_STATE()->redqueen_breakpoints, bp, entry);
g_free(bp);
err = redqueen_update_guest_debug(cpu);
if(err){
return err;
}
return 0;
}
int insert_breakpoint(CPUState *cpu, uint64_t addr, uint64_t len){
redqueen_insert_breakpoint(cpu, addr, len);
redqueen_update_guest_debug(cpu);
return 0;
}
int remove_breakpoint(CPUState *cpu, uint64_t addr, uint64_t len){
//fprintf(stderr, "%s %lx\n", __func__, addr);
redqueen_remove_breakpoint(cpu, addr, len);
redqueen_update_guest_debug(cpu);
return 0;
}
void remove_all_breakpoints(CPUState *cpu){
redqueen_remove_all_breakpoints(cpu);
}
#define PPAGE_SIZE 0x1000
#define PENTRIES 0x200
#define PLEVEL_4_SHIFT 12
#define PLEVEL_3_SHIFT 21
#define PLEVEL_2_SHIFT 30
#define PLEVEL_1_SHIFT 39
#define SIGN_EXTEND_TRESHOLD 0x100
#define SIGN_EXTEND 0xFFFF000000000000ULL
#define PAGETABLE_MASK 0x1FFFFFFFFF000ULL
#define PML4_ENTRY_MASK 0x1FFFFFFFFF000ULL
#define PML3_ENTRY_MASK 0x1FFFFC0000000ULL
#define PML2_ENTRY_MASK 0x1FFFFFFE00000ULL
#define CHECK_BIT(var,pos) !!(((var) & (1ULL<<(pos))))
static void write_address(uint64_t address, uint64_t size, uint64_t prot){
//fprintf(stderr, "%s %lx %lx %lx\n", __func__, address, size, prot);
static uint64_t next_address = PAGETABLE_MASK;
static uint64_t last_address = 0x0;
static uint64_t last_prot = 0;
if((address != next_address || prot != last_prot)){
/* do not print guard pages or empty pages without any permissions */
if(last_address && prot && (last_address+size != next_address || prot != last_prot)){
fprintf(stderr, "%016lx - %016lx %c%c%c\n",
last_address, next_address,
CHECK_BIT(last_prot, 1) ? 'W' : '-',
CHECK_BIT(last_prot, 2) ? 'U' : 'K',
!CHECK_BIT(last_prot, 63)? 'X' : '-');
}
last_address = address;
}
next_address = address+size;
last_prot = prot;
}
void print_48_paging2(uint64_t cr3){
uint64_t paging_entries_level_1[PENTRIES];
uint64_t paging_entries_level_2[PENTRIES];
uint64_t paging_entries_level_3[PENTRIES];
uint64_t paging_entries_level_4[PENTRIES];
uint64_t address_identifier_1, address_identifier_2, address_identifier_3, address_identifier_4;
uint32_t i1, i2, i3,i4;
cpu_physical_memory_rw((cr3&PAGETABLE_MASK), (uint8_t *) paging_entries_level_1, PPAGE_SIZE, false);
for(i1 = 0; i1 < 512; i1++){
if(paging_entries_level_1[i1]){
address_identifier_1 = ((uint64_t)i1) << PLEVEL_1_SHIFT;
if (i1 & SIGN_EXTEND_TRESHOLD){
address_identifier_1 |= SIGN_EXTEND;
}
if(CHECK_BIT(paging_entries_level_1[i1], 0)){ /* otherwise swapped out */
cpu_physical_memory_rw((paging_entries_level_1[i1]&PAGETABLE_MASK), (uint8_t *) paging_entries_level_2, PPAGE_SIZE, false);
for(i2 = 0; i2 < PENTRIES; i2++){
if(paging_entries_level_2[i2]){
address_identifier_2 = (((uint64_t)i2) << PLEVEL_2_SHIFT) + address_identifier_1;
if (CHECK_BIT(paging_entries_level_2[i2], 0)){ /* otherwise swapped out */
if((paging_entries_level_2[i2]&PAGETABLE_MASK) == (paging_entries_level_1[i1]&PAGETABLE_MASK)){
/* loop */
continue;
}
if (CHECK_BIT(paging_entries_level_2[i2], 7)){
write_address(address_identifier_2, 0x40000000, (uint64_t)paging_entries_level_2[i2] & ((1ULL<<63) | (1ULL<<2) | (1ULL<<1)));
}
else{
/* otherwise this PDPE references a 1GB page */
cpu_physical_memory_rw((paging_entries_level_2[i2]&PAGETABLE_MASK), (uint8_t *) paging_entries_level_3, PPAGE_SIZE, false);
for(i3 = 0; i3 < PENTRIES; i3++){
if(paging_entries_level_3[i3]){
address_identifier_3 = (((uint64_t)i3) << PLEVEL_3_SHIFT) + address_identifier_2;
if (CHECK_BIT(paging_entries_level_3[i3], 0)){ /* otherwise swapped out */
if (CHECK_BIT(paging_entries_level_3[i3], 7)){
write_address(address_identifier_3, 0x200000, (uint64_t)paging_entries_level_3[i3] & ((1ULL<<63) | (1ULL<<2) | (1ULL<<1)));
}
else{
cpu_physical_memory_rw((paging_entries_level_3[i3]&PAGETABLE_MASK), (uint8_t *) paging_entries_level_4, PPAGE_SIZE, false);
for(i4 = 0; i4 < PENTRIES; i4++){
if(paging_entries_level_4[i4]){
address_identifier_4 = (((uint64_t)i4) << PLEVEL_4_SHIFT) + address_identifier_3;
if (CHECK_BIT(paging_entries_level_4[i4], 0)){
write_address(address_identifier_4, 0x1000, (uint64_t)paging_entries_level_4[i4] & ((1ULL<<63) | (1ULL<<2) | (1ULL<<1)));
}
}
}
}
}
}
}
}
}
}
}
}
}
}
write_address(0, 0x1000, 0);
}
static uint64_t* load_page_table(uint64_t page_table_address, uint64_t* paging_entries_buffer, uint8_t level, bool read_from_snapshot, bool *success){
if(page_table_address == INVALID_ADDRESS){
*success = false;
}
if (read_from_snapshot){
*success = read_snapshot_memory(get_fast_reload_snapshot(), page_table_address, (uint8_t *) paging_entries_buffer, PPAGE_SIZE);
}
else{
cpu_physical_memory_rw(page_table_address, (uint8_t *) paging_entries_buffer, PPAGE_SIZE, false);
*success = true; /* fix this */
}
return paging_entries_buffer;
}
static uint64_t get_48_paging_phys_addr(uint64_t cr3, uint64_t addr, bool read_from_snapshot){
/* signedness broken af -> fix me! */
uint16_t pml_4_index = (addr & 0xFF8000000000ULL) >> 39;
uint16_t pml_3_index = (addr & 0x0007FC0000000UL) >> 30;
uint16_t pml_2_index = (addr & 0x000003FE00000UL) >> 21;
uint16_t pml_1_index = (addr & 0x00000001FF000UL) >> 12;
uint64_t address_identifier_4;
uint64_t paging_entries_buffer[PENTRIES];
uint64_t* paging_entries_buffer_ptr = NULL;
uint64_t page_table_address = 0;
bool success = false;
page_table_address = (cr3&PAGETABLE_MASK);
paging_entries_buffer_ptr = load_page_table(page_table_address, paging_entries_buffer, 0, read_from_snapshot, &success);
if (unlikely(success == false)){
goto fail;
}
if(paging_entries_buffer_ptr[pml_4_index]){
address_identifier_4 = ((uint64_t)pml_4_index) << PLEVEL_1_SHIFT;
if (pml_4_index & SIGN_EXTEND_TRESHOLD){
address_identifier_4 |= SIGN_EXTEND;
}
if(CHECK_BIT(paging_entries_buffer_ptr[pml_4_index], 0)){ /* otherwise swapped out */
page_table_address = (paging_entries_buffer_ptr[pml_4_index]&PAGETABLE_MASK);
paging_entries_buffer_ptr = load_page_table(page_table_address, paging_entries_buffer, 1, read_from_snapshot, &success);
if (unlikely(success == false)){
goto fail;
}
if(paging_entries_buffer_ptr[pml_3_index]){
if (CHECK_BIT(paging_entries_buffer_ptr[pml_3_index], 0)){ /* otherwise swapped out */
if (CHECK_BIT(paging_entries_buffer_ptr[pml_3_index], 7)){
/* 1GB PAGE */
return (paging_entries_buffer_ptr[pml_3_index] & PML3_ENTRY_MASK) | (0x7FFFFFFF & addr);
}
else{
page_table_address = (paging_entries_buffer_ptr[pml_3_index]&PAGETABLE_MASK);
paging_entries_buffer_ptr = load_page_table(page_table_address, paging_entries_buffer, 2, read_from_snapshot, &success);
if (unlikely(success == false)){
goto fail;
}
if(paging_entries_buffer_ptr[pml_2_index]){
if (CHECK_BIT(paging_entries_buffer_ptr[pml_2_index], 0)){ /* otherwise swapped out */
if (CHECK_BIT(paging_entries_buffer_ptr[pml_2_index], 7)){
/* 2MB PAGE */
return (paging_entries_buffer_ptr[pml_2_index] & PML2_ENTRY_MASK) | (0x3FFFFF & addr);
}
else{
page_table_address = (paging_entries_buffer_ptr[pml_2_index]&PAGETABLE_MASK);
paging_entries_buffer_ptr = load_page_table(page_table_address, paging_entries_buffer, 3, read_from_snapshot, &success);
if (unlikely(success == false)){
goto fail;
}
if(paging_entries_buffer_ptr[pml_1_index]){
if (CHECK_BIT(paging_entries_buffer_ptr[pml_1_index], 0)){
/* 4 KB PAGE */
return (paging_entries_buffer_ptr[pml_1_index] & PML4_ENTRY_MASK) | (0xFFF & addr);
}
}
}
}
}
}
}
}
}
}
fail:
return INVALID_ADDRESS;
}
//#define DEBUG_48BIT_WALK
bool read_virtual_memory(uint64_t address, uint8_t* data, uint32_t size, CPUState *cpu){
uint8_t tmp_buf[x86_64_PAGE_SIZE];
//MemTxAttrs attrs;
hwaddr phys_addr;
int asidx;
uint64_t amount_copied = 0;
kvm_arch_get_registers_fast(cpu);
CPUX86State *env = &(X86_CPU(cpu))->env;
// copy per page
while(amount_copied < size){
uint64_t len_to_copy = (size - amount_copied);
if(len_to_copy > x86_64_PAGE_SIZE)
len_to_copy = x86_64_PAGE_SIZE;
asidx = cpu_asidx_from_attrs(cpu, MEMTXATTRS_UNSPECIFIED);
//MemTxAttrs attrs = MEMTXATTRS_UNSPECIFIED;
#ifdef DEBUG_48BIT_WALK
phys_addr_2 = cpu_get_phys_page_attrs_debug(cpu, (address & x86_64_PAGE_MASK), &attrs);
#endif
phys_addr = (hwaddr)get_paging_phys_addr(cpu, env->cr[3], address) & 0xFFFFFFFFFFFFF000ULL;// != 0xFFFFFFFFFFFFFFFFULL)
//QEMU_PT_PRINTF(MEM_PREFIX, "TRANSLATE: %lx -> %lx == %lx", address, phys_addr, phys_addr_2);
#ifdef DEBUG_48BIT_WALK
assert(phys_addr == phys_addr_2);
#endif
if (phys_addr == INVALID_ADDRESS){
uint64_t next_page = (address & x86_64_PAGE_MASK) + x86_64_PAGE_SIZE;
uint64_t len_skipped =next_page-address;
if(len_skipped > size-amount_copied){
len_skipped = size-amount_copied;
}
fprintf(stderr, "Warning, read from unmapped memory:\t%lx, skipping to %lx", address, next_page);
QEMU_PT_PRINTF(MEM_PREFIX, "Warning, read from unmapped memory:\t%lx, skipping to %lx", address, next_page);
memset( data+amount_copied, ' ', len_skipped);
address += len_skipped;
amount_copied += len_skipped;
continue;
}
phys_addr += (address & ~x86_64_PAGE_MASK);
uint64_t remaining_on_page = x86_64_PAGE_SIZE - (address & ~x86_64_PAGE_MASK);
if(len_to_copy > remaining_on_page){
len_to_copy = remaining_on_page;
}
MemTxResult txt = address_space_rw(cpu_get_address_space(cpu, asidx), phys_addr, MEMTXATTRS_UNSPECIFIED, tmp_buf, len_to_copy, 0);
if(txt){
QEMU_PT_PRINTF(MEM_PREFIX, "Warning, read failed:\t%lx (%lx)", address, phys_addr);
}
memcpy(data+amount_copied, tmp_buf, len_to_copy);
address += len_to_copy;
amount_copied += len_to_copy;
}
return true;
}
bool is_addr_mapped_cr3(uint64_t address, CPUState *cpu, uint64_t cr3){
return (get_paging_phys_addr(cpu, cr3, address) != INVALID_ADDRESS);
}
bool is_addr_mapped(uint64_t address, CPUState *cpu){
CPUX86State *env = &(X86_CPU(cpu))->env;
kvm_arch_get_registers_fast(cpu);
return (get_paging_phys_addr(cpu, env->cr[3], address) != INVALID_ADDRESS);
}
bool is_addr_mapped_cr3_snapshot(uint64_t address, CPUState *cpu, uint64_t cr3){
return (get_paging_phys_addr_snapshot(cpu, cr3, address) != INVALID_ADDRESS);
}
bool dump_page_cr3_snapshot(uint64_t address, uint8_t* data, CPUState *cpu, uint64_t cr3){
fast_reload_t* snapshot = get_fast_reload_snapshot();
uint64_t phys_addr = get_paging_phys_addr_snapshot(cpu, cr3, address);
if(phys_addr == INVALID_ADDRESS){
return false;
}
else{
return read_snapshot_memory(snapshot, phys_addr, data, PPAGE_SIZE);
}
}
bool dump_page_cr3_ht(uint64_t address, uint8_t* data, CPUState *cpu, uint64_t cr3){
hwaddr phys_addr = (hwaddr) get_paging_phys_addr(cpu, cr3, address);
int asidx = cpu_asidx_from_attrs(cpu, MEMTXATTRS_UNSPECIFIED);
if(phys_addr == INVALID_ADDRESS || address_space_rw(cpu_get_address_space(cpu, asidx), phys_addr, MEMTXATTRS_UNSPECIFIED, data, 0x1000, 0)){
if(phys_addr != INVALID_ADDRESS){
fprintf(stderr, "%s: Warning, read failed:\t%lx (%lx)\n", __func__, address, phys_addr);
}
return false;
}
return true;
}
bool dump_page_ht(uint64_t address, uint8_t* data, CPUState *cpu){
CPUX86State *env = &(X86_CPU(cpu))->env;
kvm_arch_get_registers_fast(cpu);
hwaddr phys_addr = (hwaddr) get_paging_phys_addr(cpu, env->cr[3], address);
int asidx = cpu_asidx_from_attrs(cpu, MEMTXATTRS_UNSPECIFIED);
if(phys_addr == 0xffffffffffffffffULL || address_space_rw(cpu_get_address_space(cpu, asidx), phys_addr, MEMTXATTRS_UNSPECIFIED, data, 0x1000, 0)){
if(phys_addr != 0xffffffffffffffffULL){
fprintf(stderr, "%s: Warning, read failed:\t%lx (%lx)\n", __func__, address, phys_addr);
}
}
return true;
}
uint64_t disassemble_at_rip(int fd, uint64_t address, CPUState *cpu, uint64_t cr3){
csh handle;
size_t code_size = 256;
uint8_t code_ptr[256];
/* don't => GET_GLOBAL_STATE()->disassembler_word_width */
if (cs_open(CS_ARCH_X86, get_capstone_mode(GET_GLOBAL_STATE()->disassembler_word_width), &handle) != CS_ERR_OK)
assert(false);
cs_option(handle, CS_OPT_DETAIL, CS_OPT_ON);
cs_insn* insn = cs_malloc(handle);
read_virtual_memory(address, code_ptr, code_size, cpu);
int count = cs_disasm(handle, code_ptr, code_size, address, 5, &insn);
if(count > 0){
for(int i = 0; i < count; i++){
fprintf(stderr, "=> 0x%"PRIx64":\t%s\t\t%s\n", insn[i].address, insn[i].mnemonic, insn[i].op_str);
}
}
else{
fprintf(stderr, "ERROR in %s at %lx (cr3: %lx)\n", __func__, address, cr3);
}
cs_free(insn, 1);
cs_close(&handle);
return 0;
}
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