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Roll back uc_mem_protect changes

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This commit is contained in:
Chris Eagle 2015-08-28 01:37:49 -07:00
parent 71ddad9474
commit adc254cc74
4 changed files with 1 additions and 343 deletions
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19
include/unicorn/unicorn.h
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@ -427,25 +427,6 @@ uc_err uc_mem_map(uch handle, uint64_t address, size_t size);
UNICORN_EXPORT
uc_err uc_mem_map_ex(uch handle, uint64_t address, size_t size, uint32_t perms);
/*
Set memory permissions for emulation memory.
This API changes permissions on an existing memory region.
@handle: handle returned by uc_open()
@start: starting address of the memory region to be modified.
This address must be aligned to 4KB, or this will return with UC_ERR_MAP error.
@block_size: size of the memory region to be modified.
This size must be multiple of 4KB, or this will return with UC_ERR_MAP error.
@perms: New permissions for the mapped region.
This must be some combination of UC_PROT_READ | UC_PROT_WRITE,
or this will return with UC_ERR_MAP error.
@return UC_ERR_OK on success, or other value on failure (refer to uc_err enum
for detailed error).
*/
UNICORN_EXPORT
uc_err uc_mem_protect(uch handle, uint64_t start, size_t block_size, uint32_t perms);
#ifdef __cplusplus
}
#endif

3
samples/Makefile
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@ -97,7 +97,6 @@ endif
ifneq (,$(findstring x86,$(UNICORN_ARCHS)))
SOURCES += sample_x86.c
SOURCES += shellcode.c
SOURCES += mem_protect.c
endif
ifneq (,$(findstring m68k,$(UNICORN_ARCHS)))
SOURCES += sample_m68k.c
@ -112,7 +111,7 @@ all: $(BINARY)
clean:
rm -rf *.o $(OBJS_ELF) $(BINARY) $(SAMPLEDIR)/*.exe $(SAMPLEDIR)/*.static $(OBJDIR)/lib$(LIBNAME)* $(OBJDIR)/$(LIBNAME)*
rm -rf libunicorn*.so libunicorn*.lib libunicorn*.dylib unicorn*.dll unicorn*.lib
rm -rf sample_x86 sample_arm sample_arm64 sample_mips sample_sparc sample_ppc sample_m68k shellcode mem_protect
rm -rf sample_x86 sample_arm sample_arm64 sample_mips sample_sparc sample_ppc sample_m68k shellcode
$(BINARY): $(OBJS)

238
samples/mem_protect.c
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@ -1,238 +0,0 @@
#define __STDC_FORMAT_MACROS
#include <inttypes.h>
#include <string.h>
#include <unistd.h>
#include <unicorn/unicorn.h>
unsigned char PROGRAM[] =
"\xc7\x05\x00\x00\x40\x00\x41\x41\x41\x41\x90\xc7\x05\x00\x00\x40"
"\x00\x42\x42\x42\x42\x90\xc7\x05\x01\x00\x40\x00\x43\x43\x43\x43"
"\x90\xc7\x05\x01\x00\x40\x00\x44\x44\x44\x44\x90\x66\xc7\x05\x02"
"\x00\x40\x00\x45\x45\x90\x66\xc7\x05\x02\x00\x40\x00\x46\x46\x90"
"\x66\xc7\x05\x01\x00\x40\x00\x47\x47\x90\x66\xc7\x05\x01\x00\x40"
"\x00\x48\x48\x90\xc6\x05\x03\x00\x40\x00\x49\x90\xc6\x05\x03\x00"
"\x40\x00\x4a\x90\xf4";
// total size: 101 bytes
/*
bits 32
; assumes code section at 0x100000
; assumes data section at 0x400000, initially rw?
; with installed hooks toggles UC_PROT_WRITE on each nop
mov dword [0x400000], 0x41414141 ; aligned
nop
mov dword [0x400000], 0x42424242 ; aligned
nop
mov dword [0x400001], 0x43434343 ; unaligned
nop
mov dword [0x400001], 0x44444444 ; unaligned
nop
mov word [0x400002], 0x4545 ; aligned
nop
mov word [0x400002], 0x4646 ; aligned
nop
mov word [0x400001], 0x4747 ; unaligned
nop
mov word [0x400001], 0x4848 ; unaligned
nop
mov byte [0x400003], 0x49 ; unaligned
nop
mov byte [0x400003], 0x4A ; unaligned
nop
hlt ; tell hook function we are done
*/
int test_num = 0;
const uint8_t *tests[] = {
(uint8_t*)"\x41\x41\x41\x41\x00",
(uint8_t*)"\x42\x42\x42\x42\x00",
(uint8_t*)"\x42\x43\x43\x43\x43",
(uint8_t*)"\x42\x44\x44\x44\x44",
(uint8_t*)"\x42\x44\x45\x45\x44",
(uint8_t*)"\x42\x44\x46\x46\x44",
(uint8_t*)"\x42\x47\x47\x46\x44",
(uint8_t*)"\x42\x48\x48\x46\x44",
(uint8_t*)"\x42\x48\x48\x49\x44",
(uint8_t*)"\x42\x48\x48\x4A\x44",
};
static int log_num = 1;
#define CODE_SECTION 0x100000
#define CODE_SIZE 0x1000
#define DATA_SECTION 0x400000
#define DATA_SIZE 0x1000
static uint32_t current_perms = UC_PROT_READ | UC_PROT_WRITE;
static void hexdump(const char *prefix, const uint8_t *bytes, uint32_t len)
{
uint32_t i;
printf("%s", prefix);
for (i = 0; i < len; i++) {
printf("%02hhx", bytes[i]);
}
printf("\n");
}
// callback for tracing instruction
static void hook_code(uch handle, uint64_t addr, uint32_t size, void *user_data)
{
uint8_t opcode;
uint8_t bytes[5];
if (uc_mem_read(handle, addr, &opcode, 1) != UC_ERR_OK) {
printf("not ok %d - uc_mem_read fail during hook_code callback, addr: 0x%" PRIu64 "\n", log_num++, addr);
_exit(1);
}
printf("ok %d - uc_mem_read for opcode\n", log_num++);
switch (opcode) {
case 0x90: //nop
if (uc_mem_read(handle, DATA_SECTION, bytes, sizeof(bytes)) != UC_ERR_OK) {
printf("not ok %d - uc_mem_read fail for address: 0x%" PRIu64 "\n", log_num++, addr);
_exit(1);
}
printf("ok %d - uc_mem_read for test %d\n", log_num++, test_num);
if (memcmp(bytes, tests[test_num], sizeof(bytes)) == 0) {
printf("ok %d - passed test %d\n", log_num++, test_num);
}
else {
printf("not ok %d - failed test %d\n", log_num++, test_num);
hexdump("# Expected: ", tests[test_num], sizeof(bytes));
hexdump("# Received: ", bytes, sizeof(bytes));
}
test_num++;
current_perms ^= UC_PROT_WRITE;
if (uc_mem_protect(handle, DATA_SECTION, DATA_SIZE, current_perms) != UC_ERR_OK) {
printf("not ok %d - uc_mem_protect fail during hook_code callback, addr: 0x%" PRIu64 "\n", log_num++, addr);
_exit(1);
}
else {
printf("ok %d - uc_mem_protect UC_PROT_WRITE toggled\n", log_num++);
}
break;
case 0xf4: //hlt
if (uc_emu_stop(handle) != UC_ERR_OK) {
printf("not ok %d - uc_emu_stop fail during hook_code callback, addr: 0x%" PRIu64 "\n", log_num++, addr);
_exit(1);
}
else {
printf("ok %d - hlt encountered, uc_emu_stop called\n", log_num++);
}
break;
default: //all others
break;
}
}
// callback for tracing memory access (READ or WRITE)
static bool hook_mem_invalid(uch handle, uc_mem_type type,
uint64_t addr, int size, int64_t value, void *user_data)
{
uint8_t bytes[5];
switch(type) {
default:
printf("not ok %d - UC_HOOK_MEM_INVALID type: %d at 0x%" PRIu64 "\n", log_num++, type, addr);
return false;
case UC_MEM_WRITE_RO:
printf("# RO memory is being WRITTEN at 0x%"PRIx64 ", data size = %u, data value = 0x%"PRIx64 "\n", addr, size, value);
if (uc_mem_read(handle, DATA_SECTION, bytes, sizeof(bytes)) != UC_ERR_OK) {
printf("not ok %d - uc_mem_read fail for address: 0x%" PRIu64 "\n", log_num++, addr);
_exit(1);
}
printf("ok %d - uc_mem_read for ro side of test %d\n", log_num++, test_num - 1);
if (memcmp(bytes, tests[test_num - 1], sizeof(bytes)) == 0) {
printf("ok %d - passed ro side of test %d\n", log_num++, test_num - 1);
}
else {
printf("ok %d - failed ro side of test %d\n", log_num++, test_num - 1);
hexdump("# Expected: ", tests[test_num - 1], sizeof(bytes));
hexdump("# Received: ", bytes, sizeof(bytes));
}
current_perms |= UC_PROT_WRITE;
if (uc_mem_protect(handle, DATA_SECTION, DATA_SIZE, current_perms) != UC_ERR_OK) {
printf("not ok %d - uc_mem_protect fail during hook_mem_invalid callback, addr: 0x%" PRIu64 "\n", log_num++, addr);
_exit(1);
}
else {
printf("ok %d - uc_mem_protect UC_PROT_WRITE toggled\n", log_num++);
}
return true;
}
}
int main(int argc, char **argv, char **envp)
{
uch handle, trace1, trace2;
uc_err err;
printf("# Memory protect test\n");
// Initialize emulator in X86-32bit mode
err = uc_open(UC_ARCH_X86, UC_MODE_32, &handle);
if (err) {
printf("not ok %d - Failed on uc_open() with error returned: %u\n", log_num++, err);
return 1;
}
else {
printf("ok %d - uc_open() success\n", log_num++);
}
uc_mem_map_ex(handle, CODE_SECTION, CODE_SIZE, UC_PROT_READ);
uc_mem_map_ex(handle, DATA_SECTION, DATA_SIZE, current_perms);
// write machine code to be emulated to memory
if (uc_mem_write(handle, CODE_SECTION, PROGRAM, sizeof(PROGRAM))) {
printf("not ok %d - Failed to write emulation code to memory, quit!\n", log_num++);
return 2;
}
else {
printf("ok %d - Program written to memory\n", log_num++);
}
if (uc_hook_add(handle, &trace2, UC_HOOK_CODE, hook_code, NULL, 1, 0) != UC_ERR_OK) {
printf("not ok %d - Failed to install UC_HOOK_CODE handler\n", log_num++);
return 3;
}
else {
printf("ok %d - UC_HOOK_CODE installed\n", log_num++);
}
// intercept invalid memory events
if (uc_hook_add(handle, &trace1, UC_HOOK_MEM_INVALID, hook_mem_invalid, NULL) != UC_ERR_OK) {
printf("not ok %d - Failed to install UC_HOOK_MEM_INVALID handler\n", log_num++);
return 4;
}
else {
printf("ok %d - UC_HOOK_MEM_INVALID installed\n", log_num++);
}
// emulate machine code until told to stop by hook_code
printf("# BEGIN execution\n");
err = uc_emu_start(handle, CODE_SECTION, CODE_SECTION + CODE_SIZE, 0, 100);
if (err != UC_ERR_OK) {
printf("not ok %d - Failure on uc_emu_start() with error %u:%s\n", log_num++, err, uc_strerror(err));
return 5;
}
else {
printf("ok %d - uc_emu_start complete\n", log_num++);
}
printf("# END execution\n");
if (uc_close(&handle) == UC_ERR_OK) {
printf("ok %d - uc_close complete\n", log_num++);
}
else {
printf("not ok %d - uc_close complete\n", log_num++);
}
return 0;
}

84
uc.c
View File

@ -604,90 +604,6 @@ uc_err uc_mem_map(uch handle, uint64_t address, size_t size)
return uc_mem_map_ex(handle, address, size, UC_PROT_READ | UC_PROT_WRITE);
}
UNICORN_EXPORT
uc_err uc_mem_protect(uch handle, uint64_t start, size_t block_size, uint32_t perms)
{
uint64_t address;
uint64_t size;
struct uc_struct* uc = (struct uc_struct *)handle;
if (handle == 0)
// invalid handle
return UC_ERR_UCH;
if (block_size == 0)
// invalid memory mapping
return UC_ERR_MAP;
// address must be aligned to 4KB
if ((start & (4*1024 - 1)) != 0)
return UC_ERR_MAP;
// size must be multiple of 4KB
if ((block_size & (4*1024 - 1)) != 0)
return UC_ERR_MAP;
// check for only valid permissions
if ((perms & ~(UC_PROT_READ | UC_PROT_WRITE)) != 0)
return UC_ERR_MAP;
//check that users entire requested block is mapped
address = start;
size = block_size;
while (size > 0) {
uint64_t region_size;
MemoryRegion *mr = memory_mapping(uc, address);
if (mr == NULL) {
return UC_ERR_MAP;
}
region_size = int128_get64(mr->size);
if (address > mr->addr) {
//in case start address is not aligned with start of region
region_size -= address - mr->addr;
}
if (size < region_size) {
//entire region is covered
break;
}
size -= region_size;
address += region_size;
}
//Now we know entire region is mapped, so change permissions
address = start;
size = block_size;
while (size > 0) {
MemoryRegion *mr = memory_mapping(uc, address);
uint64_t region_size = int128_get64(mr->size);
if (address > mr->addr) {
//in case start address is not aligned with start of region
region_size -= address - mr->addr;
//TODO Learn how to split regions
//In this case some proper subset of the region is having it's permissions changed
//need to split region and add new portions into uc->mapped_blocks list
//In this case, there is a portion of the region with original perms: mr->addr..start
//and a portion getting new perms: start..start+block_size
//split the block and stay in the loop
}
if (size < int128_get64(mr->size)) {
//TODO Learn how to split regions
//In this case some proper subset of the region is having it's permissions changed
//need to split region and add new portions into uc->mapped_blocks list
//In this case, there is a portion of the region with new perms: start..start+block_size
//and a portion getting new perms: mr->addr+size..mr->addr+mr->size
//split the block and break
break;
}
size -= int128_get64(mr->size);
address += int128_get64(mr->size);
mr->perms = perms;
uc->readonly_mem(mr, (perms & UC_PROT_WRITE) == 0);
}
return UC_ERR_OK;
}
MemoryRegion *memory_mapping(struct uc_struct* uc, uint64_t address)
{
unsigned int i;