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x % 2^n = x & (2^n - 1), x * 2^n = x << n #64

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x % 2^n = x & (2^n - 1), x * 2^n = x << n #64

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40 changes: 20 additions & 20 deletions index.js
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Original file line number Diff line number Diff line change
Expand Up @@ -216,7 +216,7 @@
this._Kd.push([0, 0, 0, 0]);
}

var roundKeyCount = (rounds + 1) * 4;
var roundKeyCount = (rounds + 1) << 2;
var KC = this.key.length / 4;

// convert the key into ints
Expand All @@ -226,8 +226,8 @@
var index;
for (var i = 0; i < KC; i++) {
index = i >> 2;
this._Ke[index][i % 4] = tk[i];
this._Kd[rounds - index][i % 4] = tk[i];
this._Ke[index][i & 3] = tk[i];
this._Kd[rounds - index][i & 3] = tk[i];
}

// key expansion (fips-197 section 5.2)
Expand Down Expand Up @@ -269,7 +269,7 @@
var i = 0, r, c;
while (i < KC && t < roundKeyCount) {
r = t >> 2;
c = t % 4;
c = t & 3;
this._Ke[r][c] = tk[i];
this._Kd[rounds - r][c] = tk[i++];
t++;
Expand Down Expand Up @@ -306,9 +306,9 @@
for (var r = 1; r < rounds; r++) {
for (var i = 0; i < 4; i++) {
a[i] = (T1[(t[ i ] >> 24) & 0xff] ^
T2[(t[(i + 1) % 4] >> 16) & 0xff] ^
T3[(t[(i + 2) % 4] >> 8) & 0xff] ^
T4[ t[(i + 3) % 4] & 0xff] ^
T2[(t[(i + 1) & 3] >> 16) & 0xff] ^
T3[(t[(i + 2) & 3] >> 8) & 0xff] ^
T4[ t[(i + 3) & 3] & 0xff] ^
this._Ke[r][i]);
}
t = a.slice();
Expand All @@ -318,10 +318,10 @@
var result = createArray(16), tt;
for (var i = 0; i < 4; i++) {
tt = this._Ke[rounds][i];
result[4 * i ] = (S[(t[ i ] >> 24) & 0xff] ^ (tt >> 24)) & 0xff;
result[4 * i + 1] = (S[(t[(i + 1) % 4] >> 16) & 0xff] ^ (tt >> 16)) & 0xff;
result[4 * i + 2] = (S[(t[(i + 2) % 4] >> 8) & 0xff] ^ (tt >> 8)) & 0xff;
result[4 * i + 3] = (S[ t[(i + 3) % 4] & 0xff] ^ tt ) & 0xff;
result[ i << 2 ] = (S[(t[ i ] >> 24) & 0xff] ^ (tt >> 24)) & 0xff;
result[(i << 2) + 1] = (S[(t[(i + 1) & 3] >> 16) & 0xff] ^ (tt >> 16)) & 0xff;
result[(i << 2) + 2] = (S[(t[(i + 2) & 3] >> 8) & 0xff] ^ (tt >> 8)) & 0xff;
result[(i << 2) + 3] = (S[ t[(i + 3) & 3] & 0xff] ^ tt ) & 0xff;
}

return result;
Expand All @@ -344,10 +344,10 @@
// apply round transforms
for (var r = 1; r < rounds; r++) {
for (var i = 0; i < 4; i++) {
a[i] = (T5[(t[ i ] >> 24) & 0xff] ^
T6[(t[(i + 3) % 4] >> 16) & 0xff] ^
T7[(t[(i + 2) % 4] >> 8) & 0xff] ^
T8[ t[(i + 1) % 4] & 0xff] ^
a[i] = (T5[(t[ i ] >> 24) & 0xff] ^
T6[(t[(i + 3) & 3] >> 16) & 0xff] ^
T7[(t[(i + 2) & 3] >> 8) & 0xff] ^
T8[ t[(i + 1) & 3] & 0xff] ^
this._Kd[r][i]);
}
t = a.slice();
Expand All @@ -358,9 +358,9 @@
for (var i = 0; i < 4; i++) {
tt = this._Kd[rounds][i];
result[4 * i ] = (Si[(t[ i ] >> 24) & 0xff] ^ (tt >> 24)) & 0xff;
result[4 * i + 1] = (Si[(t[(i + 3) % 4] >> 16) & 0xff] ^ (tt >> 16)) & 0xff;
result[4 * i + 2] = (Si[(t[(i + 2) % 4] >> 8) & 0xff] ^ (tt >> 8)) & 0xff;
result[4 * i + 3] = (Si[ t[(i + 1) % 4] & 0xff] ^ tt ) & 0xff;
result[4 * i + 1] = (Si[(t[(i + 3) & 3] >> 16) & 0xff] ^ (tt >> 16)) & 0xff;
result[4 * i + 2] = (Si[(t[(i + 2) & 3] >> 8) & 0xff] ^ (tt >> 8)) & 0xff;
result[4 * i + 3] = (Si[ t[(i + 1) & 3] & 0xff] ^ tt ) & 0xff;
}

return result;
Expand Down Expand Up @@ -637,7 +637,7 @@
}

for (var index = 15; index >= 0; --index) {
this._counter[index] = value % 256;
this._counter[index] = value & 255;
value = parseInt(value / 256);
}
}
Expand Down Expand Up @@ -712,7 +712,7 @@
// See:https://tools.ietf.org/html/rfc2315
function pkcs7pad(data) {
data = coerceArray(data, true);
var padder = 16 - (data.length % 16);
var padder = 16 - (data.length & 15);
var result = createArray(data.length + padder);
copyArray(data, result);
for (var i = data.length; i < result.length; i++) {
Expand Down