int darm_disasm(darm_t *d, uint16_t w, uint16_t w2, uint32_t addr)
{
// if the least significant bit is not set, then this is
// an ARMv7 instruction
if((addr & 1) == 0) {
// disassemble and check for error return values
if(darm_armv7_disasm(d, (w2 << 16) | w) < 0) {
return 0;
}
else {
return 2;
}
}
// magic table constructed based on section A6.1 of the ARM manual
static uint8_t is_thumb2[0x20] = {
[b11101] = 1,
[b11110] = 1,
[b11111] = 1,
};
// check whether this is a Thumb or Thumb2 instruction
if(is_thumb2[w >> 11] == 0) {
// this is a Thumb instruction
if(darm_thumb_disasm(d, w) < 0) {
return 0;
}
else {
return 1;
}
}
// this is a Thumb2 instruction
if(darm_thumb2_disasm(d, w, w2) < 0) {
return 0;
}
else {
return 2;
}
}
/**
* Instruction Begin callback.
*/
void nd_instruction_begin_callback(DECAF_Callback_Params* params){
DEFENSIVE_CHECK0(params == NULL);
DEFENSIVE_CHECK0(getCurrentPID() != ND_GLOBAL_TRACING_PID);
CPUState* env = params->ib.env;
gva_t cur_pc = params->ib.cur_pc;
//since for thumb instruction, the last bit is '1'
gva_t cur_pc_even = cur_pc & 0xfffffffe;
if(!nd_in_blacklist(cur_pc_even)){
return;
}
//ARM Instruction
union _tmpARMInsn{
target_ulong insn;
char chars[4];
} tmpARMInsn;
//Thumb Instruction
union _tmpThumbInsn{
unsigned short insn;
char chars[2];
} tmpThumbInsn;
//Thumb2 Instruction
union _tmpThumb2Insn{
target_ulong insn;
char chars[4];
} tmpThumb2Insn;
//undefined instruction
if(cur_pc == -1){
return;
}
//the first instruction of target native method
SourcePolicy* sourcePolicy = findSourcePolicy(cur_pc_even);
if(sourcePolicy != NULL){
DECAF_printf("Step into Native\n");
sourcePolicy->handler(sourcePolicy, env);
}
//DECAF_printf("%x %x\n", cur_pc_even, lastCallSysLibAddrRet);
//return from JNI API calls/system library calls
if(cur_pc_even == lastCallJNIAddrRet){
if(lastJniHandler != NULL){
lastJniHandler(env, 0);
lastJniHandler = NULL;
lastCallJNIAddrRet = -1;
}
}
if(cur_pc_even == lastCallSysLibAddrRet){
if(lastSysLibHandler != NULL){
lastSysLibHandler(env, 0);
lastSysLibHandler = NULL;
lastCallSysLibAddrRet = -1;
}
}
//Thumb instruction
if(env->thumb == 1){
if(DECAF_read_mem(env, cur_pc_even, tmpThumbInsn.chars, 2) != -1){
darm_t d;
//darm_str_t str;
// magic table constructed based on section A6.1 of the ARM manual
static uint8_t is_thumb2[0x20] = {
[0x01d] = 1,
[0x01e] = 1,
[0x01f] = 1,
};
if(is_thumb2[tmpThumbInsn.insn >> 11]){
//Thumb2 instruction
if(DECAF_read_mem(env, cur_pc_even, tmpThumb2Insn.chars, 4) != -1){
if(darm_thumb2_disasm(&d, tmpThumb2Insn.insn & 0x0000ffff,
tmpThumb2Insn.insn >> 16, env) == 0){
//if(darm_str(&d, &str, env) == 0){
//DECAF_printf("T2 %x: %s\n", cur_pc, str.total);
//}
}
}
}else{
//Thumb instruction
if(darm_thumb_disasm(&d, tmpThumbInsn.insn, env) == 0){
//if(darm_str(&d, &str, env) == 0){
//DECAF_printf("T %x: %s\n", cur_pc, str.total);
//}
}
}
}
/**
* Instruction Begin callback.
*/
void nd_instruction_begin_callback(DECAF_Callback_Params* params){
DEFENSIVE_CHECK0(params == NULL);
DEFENSIVE_CHECK0(getCurrentPID() != ND_GLOBAL_TRACING_PID);
CPUState* env = params->ib.env;
gva_t cur_pc = params->ib.cur_pc;
//since for thumb instruction, the last bit is '1'
gva_t cur_pc_even = cur_pc & 0xfffffffe;
//ARM Instruction
union _tmpARMInsn{
target_ulong insn;
char chars[4];
} tmpARMInsn;
//Thumb Instruction
union _tmpThumbInsn{
unsigned short insn;
char chars[2];
} tmpThumbInsn;
//Thumb2 Instruction
union _tmpThumb2Insn{
target_ulong insn;
char chars[4];
} tmpThumb2Insn;
//undefined instruction
if(cur_pc == -1){
return;
}
//the first instruction of target native method
SourcePolicy* sourcePolicy = findSourcePolicy(cur_pc_even);
if(sourcePolicy != NULL){
sourcePolicy->handler(sourcePolicy, env);
}
//Thumb instruction
if(env->thumb == 1){
if(DECAF_read_mem(env, cur_pc_even, tmpThumbInsn.chars, 2) != -1){
darm_t d;
darm_str_t str;
// magic table constructed based on section A6.1 of the ARM manual
static uint8_t is_thumb2[0x20] = {
[0x01d] = 1,
[0x01e] = 1,
[0x01f] = 1,
};
if(is_thumb2[tmpThumbInsn.insn >> 11]){
//Thumb2 instruction
if(DECAF_read_mem(env, cur_pc_even, tmpThumb2Insn.chars, 4) != -1){
if(darm_thumb2_disasm(&d, tmpThumb2Insn.insn >> 16, tmpThumb2Insn.insn & 0x0000ffff) == 0){
if(darm_str(&d, &str) == 0){
//DECAF_printf("T2 %x: %s\n", cur_pc, str.total);
}
}
}
}else{
//Thumb instruction
if(darm_thumb_disasm(&d, tmpThumbInsn.insn) == 0){
if(darm_str(&d, &str) == 0){
//DECAF_printf("T %x: %s\n", cur_pc, str.total);
}
}
}
}
