skyline/app/src/main/cpp/lightswitch.cpp
2019-06-29 10:21:59 -04:00

80 lines
2.6 KiB
C++

#include <jni.h>
#include <string>
#include <unicorn/unicorn.h>
#include <syslog.h>
// code to be emulated
#define ARM_CODE "\xab\x05\x00\xb8\xaf\x05\x40\x38" // str w11, [x13]; ldrb w15, [x13]
// memory address where emulation starts
#define ADDRESS 0x10000
static void hook_block(uc_engine *uc, uint64_t address, uint32_t size, void *user_data)
{
syslog(LOG_DEBUG, ">>> Tracing basic block at 0x%" PRIx64 ", block size = 0x%x\n", size);
}
static void hook_code(uc_engine *uc, uint64_t address, uint32_t size, void *user_data)
{
syslog(LOG_DEBUG, ">>> Tracing instruction at 0x%" PRIx64 ", instruction size = 0x%x\n", size);
}
extern "C" JNIEXPORT jstring JNICALL
Java_gq_cyuubi_lightswitch_MainActivity_stringFromJNI(
JNIEnv *env,
jobject /* this */) {
uc_engine *uc;
uc_err err;
uc_hook trace1, trace2;
int64_t x11 = 0x12345678; // X11 register
int64_t x13 = 0x10000 + 0x8; // X13 register
int64_t x15 = 0x33; // X15 register
syslog(LOG_DEBUG, "Emulate ARM64 code\n");
// Initialize emulator in ARM mode
err = uc_open(UC_ARCH_ARM64, UC_MODE_ARM, &uc);
if (err) {
std::string finished = "failed!";
return env->NewStringUTF(finished.c_str());
}
// map 2MB memory for this emulation
uc_mem_map(uc, ADDRESS, 2 * 1024 * 1024, UC_PROT_ALL);
// write machine code to be emulated to memory
uc_mem_write(uc, ADDRESS, ARM_CODE, sizeof(ARM_CODE) - 1);
// initialize machine registers
uc_reg_write(uc, UC_ARM64_REG_X11, &x11);
uc_reg_write(uc, UC_ARM64_REG_X13, &x13);
uc_reg_write(uc, UC_ARM64_REG_X15, &x15);
// tracing all basic blocks with customized callback
uc_hook_add(uc, &trace1, UC_HOOK_BLOCK, (void*)hook_block, NULL, 1, 0);
// tracing one instruction at ADDRESS with customized callback
uc_hook_add(uc, &trace2, UC_HOOK_CODE, (void*)hook_code, NULL, ADDRESS, ADDRESS);
// emulate machine code in infinite time (last param = 0), or when
// finishing all the code.
err = uc_emu_start(uc, ADDRESS, ADDRESS + sizeof(ARM_CODE) -1, 0, 0);
if (err) {
syslog(LOG_DEBUG, "Failed on uc_emu_start() with error returned: %u\n", err);
}
// now print out some registers
syslog(LOG_DEBUG, ">>> Emulation done. Below is the CPU context\n");
syslog(LOG_DEBUG, ">>> As little endian, X15 should be 0x78:\n");
uc_reg_read(uc, UC_ARM64_REG_X15, &x15);
syslog(LOG_DEBUG, ">>> X15 = 0x%" PRIx64 "\n", x15);
uc_close(uc);
std::string finished = "finished!";
return env->NewStringUTF(finished.c_str());
}