Compare commits

..

2 Commits

Author SHA1 Message Date
Giulio De Pasquale
96ff9873ff VM con istruzioni cifrate. Da sistemare ancora la classe VM e i vari VMComponent 2017-05-17 11:21:40 +02:00
Giulio De Pasquale
1431f6e104 Opcode encryption in assembler 2017-05-17 11:01:47 +02:00
6 changed files with 203 additions and 78 deletions

View File

@ -10,21 +10,21 @@ int main(int argc, char *argv[]) {
std::streamsize bytecode_size; std::streamsize bytecode_size;
uint8_t * bytecode; uint8_t * bytecode;
if (argc < 2) { if (argc < 3) {
printf("Usage: %s <program>\n", argv[0]); printf("Usage: %s <opcodes_key> <program>\n", argv[0]);
return 1; return 1;
} }
/* /*
reading bytecode reading bytecode
*/ */
bytecode_if.open(argv[1], std::ios::binary | std::ios::ate); bytecode_if.open(argv[2], std::ios::binary | std::ios::ate);
bytecode_size = bytecode_if.tellg(); bytecode_size = bytecode_if.tellg();
bytecode_if.seekg(0, std::ios::beg); bytecode_if.seekg(0, std::ios::beg);
bytecode = new uint8_t[bytecode_size]; bytecode = new uint8_t[bytecode_size];
bytecode_if.read((char*)bytecode, bytecode_size); bytecode_if.read((char*)bytecode, bytecode_size);
VM vm(bytecode, bytecode_size); VM vm((uint8_t*)argv[1], bytecode, bytecode_size);
vm.run(); vm.run();
vm.status(); vm.status();
return 0; return 0;

View File

@ -3,6 +3,36 @@
#include "vmas.h" #include "vmas.h"
#include <string.h> #include <string.h>
unsigned rol(unsigned x, int L, int N) {
unsigned lsbs = x & ((1 >> L) - 1);
return (x << L) | (lsbs >> (N - L));
}
void VM::defineOpcodes(uint8_t *key) {
uint32_t i, j, keysize;
keysize = strlen((char *)key);
for (i = 0; i < keysize; i++) {
for (j = 0; j < NUM_OPS; j++) {
if (key[i] % 2) {
ops[j].setValue(rol(key[i] ^ ops[j].getValue(), key[i] % 8, 8));
} else {
ops[j].setValue(rol(key[i] ^ ops[j].getValue(), (key[i] + 1) % 8, 8));
}
}
}
for (i = 0; i < NUM_OPS; i++) {
for (j = 0; j < NUM_OPS; j++) {
ops[j].setValue(rol(ops[j].getValue(), ops[i].getValue() % 8, 8));
}
}
#ifdef DBG
DBG_INFO(("OPCODES:\n"));
for (i = 0; i < NUM_OPS; i++) {
DBG_INFO(("%s: 0x%x\n", ops[i].getName(), ops[i].getValue()));
}
#endif
return;
}
/* /*
DBG UTILS DBG UTILS
*/ */
@ -101,26 +131,31 @@ void VM::status(void) {
/* /*
CONSTRUCTORS CONSTRUCTORS
*/ */
VM::VM() { VM::VM(uint8_t *key) {
DBG_SUCC(("Creating VM without code.\n")); DBG_SUCC(("Creating VM without code.\n"));
as.allocate(); as.allocate();
init_regs(); initVariables();
defineOpcodes(key);
} }
VM::VM(uint8_t *code, uint32_t codesize) { VM::VM(uint8_t *key, uint8_t *code, uint32_t codesize) {
DBG_SUCC(("Creating VM with code.\n")); DBG_SUCC(("Creating VM with code.\n"));
if (as.allocate()) { if (as.allocate()) {
as.insCode(code, codesize); as.insCode(code, codesize);
} }
init_regs(); initVariables();
defineOpcodes(key);
} }
void VM::init_regs(void) { void VM::initVariables(void) {
uint8_t i; uint32_t i;
for (i = R0; i <= SP; i++) { for (i = R0; i < NUM_REGS; i++) {
this->regs[i] = 0; this->regs[i] = 0;
} }
for (i = MOVI; i < NUM_OPS; i++) {
ops[i].setValue(i);
}
return; return;
} }
@ -217,11 +252,11 @@ void VM::run(void) {
exec_movr(); exec_movr();
regs[IP] += MOVR_SIZE; regs[IP] += MOVR_SIZE;
break; break;
case GETM: case LOAD:
exec_getm(); exec_getm();
regs[IP] += GETM_SIZE; regs[IP] += GETM_SIZE;
break; break;
case PUTM: case STOR:
exec_putm(); exec_putm();
regs[IP] += PUTM_SIZE; regs[IP] += PUTM_SIZE;
break; break;
@ -229,7 +264,7 @@ void VM::run(void) {
exec_addi(); exec_addi();
regs[IP] += ADDI_SIZE; regs[IP] += ADDI_SIZE;
break; break;
case HALT: case SHIT:
DBG_INFO(("HALT\n")); DBG_INFO(("HALT\n"));
finished = true; finished = true;
break; break;

View File

@ -1,6 +1,7 @@
#ifndef VM_H #ifndef VM_H
#define VM_H #define VM_H
#include "vmas.h" #include "vmas.h"
#include "vmcomp.h"
#include <stdint.h> #include <stdint.h>
#define MOVI_SIZE 4 #define MOVI_SIZE 4
@ -8,7 +9,7 @@
#define GETM_SIZE 4 #define GETM_SIZE 4
#define PUTM_SIZE 4 #define PUTM_SIZE 4
#define ADDI_SIZE 4 #define ADDI_SIZE 4
enum regs { R0, R1, R2, R3, S0, S1, S2, S3, IP, BP, SP }; enum regs { R0, R1, R2, R3, S0, S1, S2, S3, IP, BP, SP, NUM_REGS };
/* /*
MEMORY LOCATIONS AND IMMEDIATES ARE 16 BITS LONG MEMORY LOCATIONS AND IMMEDIATES ARE 16 BITS LONG
@ -16,8 +17,8 @@ MEMORY LOCATIONS AND IMMEDIATES ARE 16 BITS LONG
enum ins { enum ins {
MOVI, MOVI,
MOVR, MOVR,
GETM, LOAD,
PUTM, STOR,
ADDI, ADDI,
ADDR, ADDR,
SUBI, SUBI,
@ -33,19 +34,31 @@ enum ins {
PUSH, PUSH,
POOP, POOP,
CALL, CALL,
HALT, SHIT,
NOPE NOPE,
GERM,
NUM_OPS
}; };
class VM { class VM {
private: private:
////////////////////////
// VARIABLES
////////////////////////
uint16_t regs[0xb]; uint16_t regs[0xb];
VMComponent ops[NUM_OPS];
struct flags { struct flags {
uint8_t zf : 1; uint8_t zf : 1;
uint8_t cf : 1; uint8_t cf : 1;
}; };
VMAddrSpace as; VMAddrSpace as;
////////////////////////
// FUNCTIONS
///////////////////////
void initVariables(void);
void defineOpcodes(uint8_t * key);
/* /*
DBG UTILS DBG UTILS
*/ */
@ -61,9 +74,8 @@ private:
bool exec_addi(void); bool exec_addi(void);
public: public:
VM(); VM(uint8_t * key);
VM(uint8_t *code, uint32_t codesize); VM(uint8_t * key, uint8_t *code, uint32_t codesize);
void init_regs(void);
void status(void); void status(void);
void run(); void run();
}; };

38
cpp/vmcomp.cpp Normal file
View File

@ -0,0 +1,38 @@
#include "debug.h"
#include "vmcomp.h"
VMComponent::VMComponent(void) {
name = NULL;
value = 0;
}
VMComponent::VMComponent(uint8_t * name, uint16_t value) {
this->name = name;
this->value = value;
}
uint8_t * VMComponent::getName(void){
return name;
}
uint8_t VMComponent::getValue(void) {
return value;
}
void VMComponent::setName(uint8_t * name) {
this->name = name;
return;
}
void VMComponent::setValue(uint16_t value) {
this->value = value;
return;
}
uint8_t VMComponent::toUint8(void) {
return (uint8_t) value;
}
uint16_t VMComponent::toUint16(void) {
return (uint16_t) value;
}

19
cpp/vmcomp.h Normal file
View File

@ -0,0 +1,19 @@
#ifndef VMCOMP_H
#define VMCOMP_H
#include <stdint.h>
class VMComponent {
private:
uint8_t * name;
uint16_t value;
public:
VMComponent();
VMComponent(uint8_t * name, uint16_t value);
uint8_t * getName(void);
uint8_t getValue(void);
void setName(uint8_t * name);
void setValue(uint16_t value);
uint8_t toUint8(void);
uint16_t toUint16(void);
};
#endif

View File

@ -2,33 +2,38 @@ import sys
import re import re
import struct import struct
import IPython import IPython
import copy
class InvalidRegisterException(Exception): class AssemblerException(Exception):
pass
class InvalidRegister(AssemblerException):
def __init__(self, register): def __init__(self, register):
super().__init__("Invalid register: {}".format(register)) super().__init__("Invalid register: {}".format(register))
class InvalidOperationException(Exception): class InvalidOperation(AssemblerException):
def __init__(self, operation): def __init__(self, operation):
super().__init__("Invalid operation: {}".format(operation)) super().__init__("Invalid operation: {}".format(operation))
class ExpectedImmediateException(Exception): class ExpectedImmediate(AssemblerException):
def __init__(self, value): def __init__(self, value):
super().__init__("Expected immediate, got {}".format(value)) super().__init__("Expected immediate, got {}".format(value))
class ExpectedRegisterException(Exception): class ExpectedRegister(AssemblerException):
def __init__(self, value): def __init__(self, value):
super().__init__("Expected register, got {}".format(value)) super().__init__("Expected register, got {}".format(value))
class IPOverwriteException(Exception): class IPOverwrite(AssemblerException):
def __init__(self, instruction=None): def __init__(self, instruction=None):
if instruction: if instruction:
@ -37,17 +42,23 @@ class IPOverwriteException(Exception):
super().__init__("IP can't be overwritten.") super().__init__("IP can't be overwritten.")
class InvalidValueException(Exception): class InvalidValue(AssemblerException):
def __init__(self, instruction): def __init__(self, instruction):
super().__init__("Invalid value while assembling: {}".format(instruction)) super().__init__("Invalid value while assembling: {}".format(instruction))
rol = lambda val, r_bits, max_bits: \
(val << r_bits%max_bits) & (2**max_bits-1) | \
((val & (2**max_bits-1)) >> (max_bits-(r_bits%max_bits)))
class VMAssembler: class VMAssembler:
assembled_code = bytearray()
def __init__(self, key):
self.assembled_code = bytearray()
self.define_ops(key)
def parse(self, instruction): def parse(self, instruction):
action = getattr(self, "{}".format(instruction.opcode.name)) action = getattr(self, "op_{}".format(instruction.opcode.name))
action(instruction) action(instruction)
def process_code_line(self, line): def process_code_line(self, line):
@ -64,20 +75,15 @@ class VMAssembler:
opcode = instruction.opcode opcode = instruction.opcode
reg = instruction.args[0] reg = instruction.args[0]
imm = instruction.args[1] imm = instruction.args[1]
print(instruction) if reg.name == "ip":
if reg.name != "ip": raise IPOverwrite(instruction)
if imm.isimm(): if not imm.isimm():
if reg.isreg(): raise ExpectedImmediate(imm)
if opcode.uint8() and reg.uint8() and imm.uint16(): if not reg.isreg():
self.assembled_code += opcode.uint8() + reg.uint8() + imm.uint16() raise ExpectedRegister(reg)
else: if not opcode.uint8() or not reg.uint8() or not imm.uint16():
raise InvalidValueException(instruction) raise InvalidValue(instruction)
else: self.assembled_code += opcode.uint8() + reg.uint8() + imm.uint16()
raise ExpectedRegisterException(reg)
else:
raise ExpectedImmediateException(imm)
else:
raise IPOverwriteException(instruction)
return return
def reg2reg(self, instruction): def reg2reg(self, instruction):
@ -90,47 +96,55 @@ class VMAssembler:
opcode = instruction.opcode opcode = instruction.opcode
imm = instruction.args[0] imm = instruction.args[0]
reg = instruction.args[1] reg = instruction.args[1]
print(instruction) if reg.name == "ip":
if reg.name != "ip": raise IPOverwrite(instruction)
if imm.isimm(): if not imm.isimm():
if reg.isreg(): raise ExpectedImmediate(imm)
if opcode.uint8() and reg.uint8() and imm.uint16(): if not reg.isreg():
self.assembled_code += opcode.uint8() + imm.uint16() + reg.uint8() raise ExpectedRegister(reg)
else: if not opcode.uint8() or not reg.uint8() or not imm.uint16():
raise InvalidValueException(instruction) raise InvalidValue(instruction)
else: self.assembled_code += opcode.uint8() + imm.uint16() + reg.uint8()
raise ExpectedRegisterException(reg)
else:
raise ExpectedImmediateException(imm)
else:
raise IPOverwriteException(instruction)
return return
def imm(self, instruction): def imm(self, instruction):
return return
def movi(self, instruction): def op_movi(self, instruction):
self.imm2reg(instruction) self.imm2reg(instruction)
def movr(self, instruction): def op_movr(self, instruction):
self.reg2reg(instruction) self.reg2reg(instruction)
def getm(self, instruction): def op_load(self, instruction):
self.imm2reg(instruction) self.imm2reg(instruction)
def putm(self, instruction): def op_stor(self, instruction):
self.reg2imm(instruction) self.reg2imm(instruction)
def addi(self, instruction): def op_addi(self, instruction):
self.imm2reg(instruction) self.imm2reg(instruction)
def define_ops(self, key):
key_ba = bytearray(key, 'utf-8')
olds = copy.deepcopy(ops)
for b in key_ba:
for op_com in ops:
if b % 2:
op_com.set_value(rol(b ^ op_com.value, b % 8, 8))
else:
op_com.set_value(rol(b ^ op_com.value, (b + 1) % 8, 8))
for i in ops:
for j in ops:
j.set_value(rol(j.value, i.value % 8, 8))
for o, n in zip(olds, ops):
print("{} : {}->{}".format(o.name, hex(o.value), hex(n.value)))
class VMComponent: class VMComponent:
""" """
Represents a register, operation or an immediate the VM recognizes Represents a register, operation or an immediate the VM recognizes
""" """
name = ""
value = ""
def __init__(self, name, value): def __init__(self, name, value):
self.name = name.casefold() self.name = name.casefold()
@ -139,6 +153,12 @@ class VMComponent:
def __repr__(self): def __repr__(self):
return "{}".format(self.name) return "{}".format(self.name)
def set_name(self, name):
self.name = name
def set_value(self, value):
self.value = value
def uint8(self): def uint8(self):
numre = re.compile("^[0-9]+$") numre = re.compile("^[0-9]+$")
if isinstance(self.value, int): if isinstance(self.value, int):
@ -203,8 +223,8 @@ class VMInstruction:
op_names = ["MOVI", op_names = ["MOVI",
"MOVR", "MOVR",
"GETM", "LOAD",
"PUTM", "STOR",
"ADDI", "ADDI",
"ADDR", "ADDR",
"SUBI", "SUBI",
@ -220,8 +240,10 @@ op_names = ["MOVI",
"PUSH", "PUSH",
"POOP", "POOP",
"CALL", "CALL",
"HALT", "SHIT",
"NOPE"] "NOPE",
"GERM"]
reg_names = ["R0", "R1", "R2", "R3", "S0", "S1", "S2", "S3", "IP", "BP", "SP"] reg_names = ["R0", "R1", "R2", "R3", "S0", "S1", "S2", "S3", "IP", "BP", "SP"]
section_names = ["DATA:", "CODE:", "STACK:"] section_names = ["DATA:", "CODE:", "STACK:"]
section_flags = {s.casefold(): i + 1 for i, s in enumerate(section_names)} section_flags = {s.casefold(): i + 1 for i, s in enumerate(section_names)}
@ -230,7 +252,6 @@ regs = [VMComponent(s.casefold(), i) for i, s in enumerate(reg_names)]
def value_from_list(fromlist, name): def value_from_list(fromlist, name):
global ops, regs
""" """
returns a tuple (name, value) from a list of VMComponents returns a tuple (name, value) from a list of VMComponents
""" """
@ -238,9 +259,9 @@ def value_from_list(fromlist, name):
if el.name == name: if el.name == name:
return (el.name, el.value) return (el.name, el.value)
if fromlist == ops: if fromlist == ops:
raise InvalidOperationException(name) raise InvalidOperation(name)
elif fromlist == regs: elif fromlist == regs:
raise InvalidRegisterException(name) raise InvalidRegister(name)
def name_from_list(fromlist, value): def name_from_list(fromlist, value):
@ -259,12 +280,12 @@ def assemble_data(line):
def main(): def main():
if len(sys.argv) < 3: if len(sys.argv) < 4:
print("Usage: {} file_to_assemble output".format(sys.argv[0])) print("Usage: {} opcodes_key file_to_assemble output".format(sys.argv[0]))
return return
vma = VMAssembler() vma = VMAssembler(sys.argv[1])
with open(sys.argv[1], 'r') as f: with open(sys.argv[2], 'r') as f:
gen = (line.casefold().strip("\n") for line in f if line != "\n") gen = (line.casefold().strip() for line in f if line != "\n")
flag = None flag = None
for line in gen: for line in gen:
@ -278,7 +299,7 @@ def main():
if not flag: if not flag:
sys.stderr.write( sys.stderr.write(
"Nothing was assembled! Did you use the section delimiters?\n") "Nothing was assembled! Did you use the section delimiters?\n")
with open(sys.argv[2], 'wb') as f: with open(sys.argv[3], 'wb') as f:
f.write(vma.assembled_code) f.write(vma.assembled_code)
if __name__ == '__main__': if __name__ == '__main__':