ncmdump/aes.cpp

306 lines
9.2 KiB
C++
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

#include "aes.h"
unsigned char AES::sBox[] =
{ // 0 1 2 3 4 5 6 7 8 9 a b c d e f
0x63, 0x7c, 0x77, 0x7b, 0xf2, 0x6b, 0x6f, 0xc5, 0x30, 0x01, 0x67, 0x2b, 0xfe, 0xd7, 0xab, 0x76, //0
0xca, 0x82, 0xc9, 0x7d, 0xfa, 0x59, 0x47, 0xf0, 0xad, 0xd4, 0xa2, 0xaf, 0x9c, 0xa4, 0x72, 0xc0, //1
0xb7, 0xfd, 0x93, 0x26, 0x36, 0x3f, 0xf7, 0xcc, 0x34, 0xa5, 0xe5, 0xf1, 0x71, 0xd8, 0x31, 0x15, //2
0x04, 0xc7, 0x23, 0xc3, 0x18, 0x96, 0x05, 0x9a, 0x07, 0x12, 0x80, 0xe2, 0xeb, 0x27, 0xb2, 0x75, //3
0x09, 0x83, 0x2c, 0x1a, 0x1b, 0x6e, 0x5a, 0xa0, 0x52, 0x3b, 0xd6, 0xb3, 0x29, 0xe3, 0x2f, 0x84, //4
0x53, 0xd1, 0x00, 0xed, 0x20, 0xfc, 0xb1, 0x5b, 0x6a, 0xcb, 0xbe, 0x39, 0x4a, 0x4c, 0x58, 0xcf, //5
0xd0, 0xef, 0xaa, 0xfb, 0x43, 0x4d, 0x33, 0x85, 0x45, 0xf9, 0x02, 0x7f, 0x50, 0x3c, 0x9f, 0xa8, //6
0x51, 0xa3, 0x40, 0x8f, 0x92, 0x9d, 0x38, 0xf5, 0xbc, 0xb6, 0xda, 0x21, 0x10, 0xff, 0xf3, 0xd2, //7
0xcd, 0x0c, 0x13, 0xec, 0x5f, 0x97, 0x44, 0x17, 0xc4, 0xa7, 0x7e, 0x3d, 0x64, 0x5d, 0x19, 0x73, //8
0x60, 0x81, 0x4f, 0xdc, 0x22, 0x2a, 0x90, 0x88, 0x46, 0xee, 0xb8, 0x14, 0xde, 0x5e, 0x0b, 0xdb, //9
0xe0, 0x32, 0x3a, 0x0a, 0x49, 0x06, 0x24, 0x5c, 0xc2, 0xd3, 0xac, 0x62, 0x91, 0x95, 0xe4, 0x79, //a
0xe7, 0xc8, 0x37, 0x6d, 0x8d, 0xd5, 0x4e, 0xa9, 0x6c, 0x56, 0xf4, 0xea, 0x65, 0x7a, 0xae, 0x08, //b
0xba, 0x78, 0x25, 0x2e, 0x1c, 0xa6, 0xb4, 0xc6, 0xe8, 0xdd, 0x74, 0x1f, 0x4b, 0xbd, 0x8b, 0x8a, //c
0x70, 0x3e, 0xb5, 0x66, 0x48, 0x03, 0xf6, 0x0e, 0x61, 0x35, 0x57, 0xb9, 0x86, 0xc1, 0x1d, 0x9e, //d
0xe1, 0xf8, 0x98, 0x11, 0x69, 0xd9, 0x8e, 0x94, 0x9b, 0x1e, 0x87, 0xe9, 0xce, 0x55, 0x28, 0xdf, //e
0x8c, 0xa1, 0x89, 0x0d, 0xbf, 0xe6, 0x42, 0x68, 0x41, 0x99, 0x2d, 0x0f, 0xb0, 0x54, 0xbb, 0x16 //f
};
unsigned char AES::invSBox[] =
{ /* 0 1 2 3 4 5 6 7 8 9 a b c d e f */
0x52, 0x09, 0x6a, 0xd5, 0x30, 0x36, 0xa5, 0x38, 0xbf, 0x40, 0xa3, 0x9e, 0x81, 0xf3, 0xd7, 0xfb, //0
0x7c, 0xe3, 0x39, 0x82, 0x9b, 0x2f, 0xff, 0x87, 0x34, 0x8e, 0x43, 0x44, 0xc4, 0xde, 0xe9, 0xcb, //1
0x54, 0x7b, 0x94, 0x32, 0xa6, 0xc2, 0x23, 0x3d, 0xee, 0x4c, 0x95, 0x0b, 0x42, 0xfa, 0xc3, 0x4e, //2
0x08, 0x2e, 0xa1, 0x66, 0x28, 0xd9, 0x24, 0xb2, 0x76, 0x5b, 0xa2, 0x49, 0x6d, 0x8b, 0xd1, 0x25, //3
0x72, 0xf8, 0xf6, 0x64, 0x86, 0x68, 0x98, 0x16, 0xd4, 0xa4, 0x5c, 0xcc, 0x5d, 0x65, 0xb6, 0x92, //4
0x6c, 0x70, 0x48, 0x50, 0xfd, 0xed, 0xb9, 0xda, 0x5e, 0x15, 0x46, 0x57, 0xa7, 0x8d, 0x9d, 0x84, //5
0x90, 0xd8, 0xab, 0x00, 0x8c, 0xbc, 0xd3, 0x0a, 0xf7, 0xe4, 0x58, 0x05, 0xb8, 0xb3, 0x45, 0x06, //6
0xd0, 0x2c, 0x1e, 0x8f, 0xca, 0x3f, 0x0f, 0x02, 0xc1, 0xaf, 0xbd, 0x03, 0x01, 0x13, 0x8a, 0x6b, //7
0x3a, 0x91, 0x11, 0x41, 0x4f, 0x67, 0xdc, 0xea, 0x97, 0xf2, 0xcf, 0xce, 0xf0, 0xb4, 0xe6, 0x73, //8
0x96, 0xac, 0x74, 0x22, 0xe7, 0xad, 0x35, 0x85, 0xe2, 0xf9, 0x37, 0xe8, 0x1c, 0x75, 0xdf, 0x6e, //9
0x47, 0xf1, 0x1a, 0x71, 0x1d, 0x29, 0xc5, 0x89, 0x6f, 0xb7, 0x62, 0x0e, 0xaa, 0x18, 0xbe, 0x1b, //a
0xfc, 0x56, 0x3e, 0x4b, 0xc6, 0xd2, 0x79, 0x20, 0x9a, 0xdb, 0xc0, 0xfe, 0x78, 0xcd, 0x5a, 0xf4, //b
0x1f, 0xdd, 0xa8, 0x33, 0x88, 0x07, 0xc7, 0x31, 0xb1, 0x12, 0x10, 0x59, 0x27, 0x80, 0xec, 0x5f, //c
0x60, 0x51, 0x7f, 0xa9, 0x19, 0xb5, 0x4a, 0x0d, 0x2d, 0xe5, 0x7a, 0x9f, 0x93, 0xc9, 0x9c, 0xef, //d
0xa0, 0xe0, 0x3b, 0x4d, 0xae, 0x2a, 0xf5, 0xb0, 0xc8, 0xeb, 0xbb, 0x3c, 0x83, 0x53, 0x99, 0x61, //e
0x17, 0x2b, 0x04, 0x7e, 0xba, 0x77, 0xd6, 0x26, 0xe1, 0x69, 0x14, 0x63, 0x55, 0x21, 0x0c, 0x7d //f
};
unsigned char AES::rcon[] = { 0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36 };
AES::AES()
{
//If no key is input,use the default key
unsigned char key[16] = {
0x0f, 0x15, 0x71, 0xc9,
0x47, 0xd9, 0xe8, 0x59,
0x0c, 0xb7, 0xad, 0xd6,
0xaf, 0x7f, 0x67, 0x98
};
setKey(key);
keyExpansion();
}
AES::AES(const unsigned char *key){
setKey(key);
keyExpansion();
}
void AES::setKey(const unsigned char key[]){
mNb = 4;
mNk = 4;
mNr = 10;
memcpy(mKey, key, mNk * 4);
}
void AES::keyExpansion() {
//the first mNk words will be filled in mW derictly
for (int i = 0; i < mNk; i++){
for (int j = 0; j < 4; j++){
//arranged vertically
mW[i][j] = mKey[j+i*4];
}
}
//generate the secret key words
for (int i = mNk; i < mNb*(mNr + 1); i++){
//last secret key word
unsigned char pre_w[4];
for (int k = 0; k < 4; k++){
pre_w[k] = mW[i-1][k];
}
if(i%mNk == 0){
rotWord(pre_w);
subWord(pre_w);
pre_w[0] = pre_w[0] ^= rcon[i / mNk - 1];
}
else if ((mNk>6)&&(i%mNk==4)){
subWord(pre_w);
}
for (int k = 0; k < 4; k++){
mW[i][k] = pre_w[k] ^ mW[i-mNk][k];
}
}
}
void AES::subBytes(unsigned char state[][4])
{
for (int i = 0; i < 4; i++){
for (int j = 0; j < 4; j++){
state[i][j] = sBox[state[i][j]];
}
}
}
void AES::shiftRows(unsigned char state[][4])
{
unsigned char t[4];
for (int i = 1; i < 4; i++){
for (int j = 0; j < 4; j++){
t[j] = state[i][(i + j) % 4];
}
for (int j = 0; j < 4; j++){
state[i][j] = t[j];
}
}
}
void AES::mixColumns(unsigned char state[][4])
{
unsigned char t[4];
for (int j = 0; j < 4; j++){
for (int i = 0; i < 4; i++){
t[i] = state[i][j];
}
for (int i = 0; i < 4; i++){
state[i][j] = GF28Multi(t[i], 0x02)
^ GF28Multi(t[(i + 1) % 4], 0x03)
^ GF28Multi(t[(i + 2) % 4], 0x01)
^ GF28Multi(t[(i + 3) % 4], 0x01);
}
}
}
void AES::addRoundKey(unsigned char state[][4], unsigned char w[][4])
{
for (int i = 0; i < 4; i++){
for (int j = 0; j < 4; j++){
state[i][j] ^= w[i][j];
}
}
}
void AES::invSubBytes(unsigned char state[][4])
{
for (int i = 0; i < 4; i++){
for (int j = 0; j < 4; j++){
state[i][j] = invSBox[state[i][j]];
}
}
}
void AES::invShiftRows(unsigned char state[][4])
{
unsigned char t[4];
for (int i = 0; i < 4; i++){
for (int j = 0; j < 4; j++){
t[j] = state[i][(j-i + 4) % 4];
}
for (int j = 0; j < 4; j++){
state[i][j] = t[j];
}
}
}
void AES::invMixColumns(unsigned char state[][4])
{
unsigned char t[4];
//calculate columns by columns
for (int j = 0; j < 4; j++){
for (int i = 0; i < 4; i++){
t[i] = state[i][j];
}
for (int i = 0; i < 4; i++){
state[i][j] = GF28Multi(t[i], 0x0e)
^ GF28Multi(t[(i+1)%4],0x0b)
^ GF28Multi(t[(i+2)%4],0x0d)
^ GF28Multi(t[(i+3)%4],0x09);
}
}
}
void AES::rotWord(unsigned char w[])
{
unsigned char t;
t = w[0];
w[0] = w[1];
w[1] = w[2];
w[2] = w[3];
w[3] = t;
}
void AES::subWord(unsigned char w[])
{
for (int i = 0; i < 4; i++){
w[i] = sBox[w[i]];
}
}
//calculate the least significant unsigned char only for we only need
//the least significant byte
unsigned char AES::GF28Multi(unsigned char s,unsigned char a){
unsigned char t[4];
unsigned char result = 0;
t[0] = s;
//calculate s*{02}s*{03}s*{04}
for (int i = 1; i < 4; i++){
t[i] = t[i - 1] << 1;
if (t[i - 1] & 0x80){
t[i] ^= 0x1b;
}
}
//multiply a and s bit by bit and sum together
for (int i = 0; i < 4; i++){
if ((a >> i) & 0x01){
result ^= t[i];
}
}
return result;
}
void AES::encrypt(const unsigned char data[16], unsigned char out[16])
{
unsigned char state[4][4];
unsigned char key[4][4];
for (int i = 0; i < 4; i++){
for (int j = 0; j < 4; j++){
state[i][j] = data[i+j*4];
}
}
getKeyAt(key, 0);
addRoundKey(state, key);
for (int i = 1; i <= mNr; i++){
subBytes(state);
shiftRows(state);
if (i != mNr){
mixColumns(state);
}
getKeyAt(key, i);
addRoundKey(state, key);
}
for (int i = 0; i < 4; i++){
for (int j = 0; j < 4; j++){
out[i+j*4] = state[i][j];
}
}
}
void AES::decrypt(const unsigned char data[16], unsigned char out[16])
{
unsigned char state[4][4];
unsigned char key[4][4];
for (int i = 0; i < 4; i++){
for (int j = 0; j < 4; j++){
state[i][j] = data[i+j*4];
}
}
getKeyAt(key, mNr);
addRoundKey(state,key);
for (int i = (mNr - 1); i >= 0; i--){
invShiftRows(state);
invSubBytes(state);
getKeyAt(key, i);
addRoundKey(state,key);
if (i){
invMixColumns(state);
}
}
for (int i = 0; i < 4; i++){
for (int j = 0; j < 4; j++){
out[i + j * 4] = state[i][j];
}
}
}
//get the secret key for round "index",which will
//be arranged vetically
void AES::getKeyAt(unsigned char key[][4], int index){
for (int i = index*4; i < index*4+4; i++){
for (int j = 0; j < 4; j++){
key[j][i-index*4] = mW[i][j];
}
}
}
AES::~AES()
{
}