Press n or j to go to the next uncovered block, b, p or k for the previous block.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 | 4x 4x 4x 3x 1x | // PKCS7
export function removePadding (buffer) {
const outputBytes = buffer.byteLength;
const paddingBytes = outputBytes && (new DataView(buffer)).getUint8(outputBytes - 1);
if (paddingBytes)
return buffer.slice(0, outputBytes - paddingBytes);
else
return buffer;
}
class AESDecryptor {
constructor () {
// Static after running initTable
this.rcon = [0x0, 0x1, 0x2, 0x4, 0x8, 0x10, 0x20, 0x40, 0x80, 0x1b, 0x36];
this.subMix = [new Uint32Array(256), new Uint32Array(256), new Uint32Array(256), new Uint32Array(256)];
this.invSubMix = [new Uint32Array(256), new Uint32Array(256), new Uint32Array(256), new Uint32Array(256)];
this.sBox = new Uint32Array(256);
this.invSBox = new Uint32Array(256);
// Changes during runtime
this.key = new Uint32Array(0);
this.initTable();
}
// Using view.getUint32() also swaps the byte order.
uint8ArrayToUint32Array_ (arrayBuffer) {
let view = new DataView(arrayBuffer);
let newArray = new Uint32Array(4);
for (let i = 0; i < 4; i++)
newArray[i] = view.getUint32(i * 4);
return newArray;
}
initTable () {
let sBox = this.sBox;
let invSBox = this.invSBox;
let subMix = this.subMix;
let subMix0 = subMix[0];
let subMix1 = subMix[1];
let subMix2 = subMix[2];
let subMix3 = subMix[3];
let invSubMix = this.invSubMix;
let invSubMix0 = invSubMix[0];
let invSubMix1 = invSubMix[1];
let invSubMix2 = invSubMix[2];
let invSubMix3 = invSubMix[3];
let d = new Uint32Array(256);
let x = 0;
let xi = 0;
let i = 0;
for (i = 0; i < 256; i++) {
if (i < 128)
d[i] = i << 1;
else
d[i] = (i << 1) ^ 0x11b;
}
for (i = 0; i < 256; i++) {
let sx = xi ^ (xi << 1) ^ (xi << 2) ^ (xi << 3) ^ (xi << 4);
sx = (sx >>> 8) ^ (sx & 0xff) ^ 0x63;
sBox[x] = sx;
invSBox[sx] = x;
// Compute multiplication
let x2 = d[x];
let x4 = d[x2];
let x8 = d[x4];
// Compute sub/invSub bytes, mix columns tables
let t = (d[sx] * 0x101) ^ (sx * 0x1010100);
subMix0[x] = (t << 24) | (t >>> 8);
subMix1[x] = (t << 16) | (t >>> 16);
subMix2[x] = (t << 8) | (t >>> 24);
subMix3[x] = t;
// Compute inv sub bytes, inv mix columns tables
t = (x8 * 0x1010101) ^ (x4 * 0x10001) ^ (x2 * 0x101) ^ (x * 0x1010100);
invSubMix0[sx] = (t << 24) | (t >>> 8);
invSubMix1[sx] = (t << 16) | (t >>> 16);
invSubMix2[sx] = (t << 8) | (t >>> 24);
invSubMix3[sx] = t;
// Compute next counter
if (!x) {
x = xi = 1;
} else {
x = x2 ^ d[d[d[x8 ^ x2]]];
xi ^= d[d[xi]];
}
}
}
expandKey (keyBuffer) {
// convert keyBuffer to Uint32Array
let key = this.uint8ArrayToUint32Array_(keyBuffer);
let sameKey = true;
let offset = 0;
while (offset < key.length && sameKey) {
sameKey = (key[offset] === this.key[offset]);
offset++;
}
if (sameKey)
return;
this.key = key;
let keySize = this.keySize = key.length;
if (keySize !== 4 && keySize !== 6 && keySize !== 8)
throw new Error('Invalid aes key size=' + keySize);
let ksRows = this.ksRows = (keySize + 6 + 1) * 4;
let ksRow;
let invKsRow;
let keySchedule = this.keySchedule = new Uint32Array(ksRows);
let invKeySchedule = this.invKeySchedule = new Uint32Array(ksRows);
let sbox = this.sBox;
let rcon = this.rcon;
let invSubMix = this.invSubMix;
let invSubMix0 = invSubMix[0];
let invSubMix1 = invSubMix[1];
let invSubMix2 = invSubMix[2];
let invSubMix3 = invSubMix[3];
let prev;
let t;
for (ksRow = 0; ksRow < ksRows; ksRow++) {
if (ksRow < keySize) {
prev = keySchedule[ksRow] = key[ksRow];
continue;
}
t = prev;
if (ksRow % keySize === 0) {
// Rot word
t = (t << 8) | (t >>> 24);
// Sub word
t = (sbox[t >>> 24] << 24) | (sbox[(t >>> 16) & 0xff] << 16) | (sbox[(t >>> 8) & 0xff] << 8) | sbox[t & 0xff];
// Mix Rcon
t ^= rcon[(ksRow / keySize) | 0] << 24;
} else if (keySize > 6 && ksRow % keySize === 4) {
// Sub word
t = (sbox[t >>> 24] << 24) | (sbox[(t >>> 16) & 0xff] << 16) | (sbox[(t >>> 8) & 0xff] << 8) | sbox[t & 0xff];
}
keySchedule[ksRow] = prev = (keySchedule[ksRow - keySize] ^ t) >>> 0;
}
for (invKsRow = 0; invKsRow < ksRows; invKsRow++) {
ksRow = ksRows - invKsRow;
if (invKsRow & 3)
t = keySchedule[ksRow];
else
t = keySchedule[ksRow - 4];
if (invKsRow < 4 || ksRow <= 4)
invKeySchedule[invKsRow] = t;
else
invKeySchedule[invKsRow] = invSubMix0[sbox[t >>> 24]] ^ invSubMix1[sbox[(t >>> 16) & 0xff]] ^ invSubMix2[sbox[(t >>> 8) & 0xff]] ^ invSubMix3[sbox[t & 0xff]];
invKeySchedule[invKsRow] = invKeySchedule[invKsRow] >>> 0;
}
}
// Adding this as a method greatly improves performance.
networkToHostOrderSwap (word) {
return (word << 24) | ((word & 0xff00) << 8) | ((word & 0xff0000) >> 8) | (word >>> 24);
}
decrypt (inputArrayBuffer, offset, aesIV, removePKCS7Padding) {
let nRounds = this.keySize + 6;
let invKeySchedule = this.invKeySchedule;
let invSBOX = this.invSBox;
let invSubMix = this.invSubMix;
let invSubMix0 = invSubMix[0];
let invSubMix1 = invSubMix[1];
let invSubMix2 = invSubMix[2];
let invSubMix3 = invSubMix[3];
let initVector = this.uint8ArrayToUint32Array_(aesIV);
let initVector0 = initVector[0];
let initVector1 = initVector[1];
let initVector2 = initVector[2];
let initVector3 = initVector[3];
let inputInt32 = new Int32Array(inputArrayBuffer);
let outputInt32 = new Int32Array(inputInt32.length);
let t0, t1, t2, t3;
let s0, s1, s2, s3;
let inputWords0, inputWords1, inputWords2, inputWords3;
let ksRow, i;
let swapWord = this.networkToHostOrderSwap;
while (offset < inputInt32.length) {
inputWords0 = swapWord(inputInt32[offset]);
inputWords1 = swapWord(inputInt32[offset + 1]);
inputWords2 = swapWord(inputInt32[offset + 2]);
inputWords3 = swapWord(inputInt32[offset + 3]);
s0 = inputWords0 ^ invKeySchedule[0];
s1 = inputWords3 ^ invKeySchedule[1];
s2 = inputWords2 ^ invKeySchedule[2];
s3 = inputWords1 ^ invKeySchedule[3];
ksRow = 4;
// Iterate through the rounds of decryption
for (i = 1; i < nRounds; i++) {
t0 = invSubMix0[s0 >>> 24] ^ invSubMix1[(s1 >> 16) & 0xff] ^ invSubMix2[(s2 >> 8) & 0xff] ^ invSubMix3[s3 & 0xff] ^ invKeySchedule[ksRow];
t1 = invSubMix0[s1 >>> 24] ^ invSubMix1[(s2 >> 16) & 0xff] ^ invSubMix2[(s3 >> 8) & 0xff] ^ invSubMix3[s0 & 0xff] ^ invKeySchedule[ksRow + 1];
t2 = invSubMix0[s2 >>> 24] ^ invSubMix1[(s3 >> 16) & 0xff] ^ invSubMix2[(s0 >> 8) & 0xff] ^ invSubMix3[s1 & 0xff] ^ invKeySchedule[ksRow + 2];
t3 = invSubMix0[s3 >>> 24] ^ invSubMix1[(s0 >> 16) & 0xff] ^ invSubMix2[(s1 >> 8) & 0xff] ^ invSubMix3[s2 & 0xff] ^ invKeySchedule[ksRow + 3];
// Update state
s0 = t0;
s1 = t1;
s2 = t2;
s3 = t3;
ksRow = ksRow + 4;
}
// Shift rows, sub bytes, add round key
t0 = ((invSBOX[s0 >>> 24] << 24) ^ (invSBOX[(s1 >> 16) & 0xff] << 16) ^ (invSBOX[(s2 >> 8) & 0xff] << 8) ^ invSBOX[s3 & 0xff]) ^ invKeySchedule[ksRow];
t1 = ((invSBOX[s1 >>> 24] << 24) ^ (invSBOX[(s2 >> 16) & 0xff] << 16) ^ (invSBOX[(s3 >> 8) & 0xff] << 8) ^ invSBOX[s0 & 0xff]) ^ invKeySchedule[ksRow + 1];
t2 = ((invSBOX[s2 >>> 24] << 24) ^ (invSBOX[(s3 >> 16) & 0xff] << 16) ^ (invSBOX[(s0 >> 8) & 0xff] << 8) ^ invSBOX[s1 & 0xff]) ^ invKeySchedule[ksRow + 2];
t3 = ((invSBOX[s3 >>> 24] << 24) ^ (invSBOX[(s0 >> 16) & 0xff] << 16) ^ (invSBOX[(s1 >> 8) & 0xff] << 8) ^ invSBOX[s2 & 0xff]) ^ invKeySchedule[ksRow + 3];
ksRow = ksRow + 3;
// Write
outputInt32[offset] = swapWord(t0 ^ initVector0);
outputInt32[offset + 1] = swapWord(t3 ^ initVector1);
outputInt32[offset + 2] = swapWord(t2 ^ initVector2);
outputInt32[offset + 3] = swapWord(t1 ^ initVector3);
// reset initVector to last 4 unsigned int
initVector0 = inputWords0;
initVector1 = inputWords1;
initVector2 = inputWords2;
initVector3 = inputWords3;
offset = offset + 4;
}
return removePKCS7Padding ? removePadding(outputInt32.buffer) : outputInt32.buffer;
}
destroy () {
this.key = undefined;
this.keySize = undefined;
this.ksRows = undefined;
this.sBox = undefined;
this.invSBox = undefined;
this.subMix = undefined;
this.invSubMix = undefined;
this.keySchedule = undefined;
this.invKeySchedule = undefined;
this.rcon = undefined;
}
}
export default AESDecryptor;
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