// // Decompiled by Procyon v0.6.0 // package org.bouncycastle.crypto.engines; import org.bouncycastle.util.Integers; import org.bouncycastle.util.Pack; public class ChaChaEngine extends Salsa20Engine { public ChaChaEngine() { } public ChaChaEngine(final int n) { super(n); } @Override public String getAlgorithmName() { return "ChaCha" + this.rounds; } @Override protected void advanceCounter(final long n) { final int n2 = (int)(n >>> 32); final int n3 = (int)n; if (n2 > 0) { final int[] engineState = this.engineState; final int n4 = 13; engineState[n4] += n2; } final int n5 = this.engineState[12]; final int[] engineState2 = this.engineState; final int n6 = 12; engineState2[n6] += n3; if (n5 != 0 && this.engineState[12] < n5) { final int[] engineState3 = this.engineState; final int n7 = 13; ++engineState3[n7]; } } @Override protected void advanceCounter() { if (++this.engineState[12] == 0) { final int[] engineState = this.engineState; final int n = 13; ++engineState[n]; } } @Override protected void retreatCounter(final long n) { final int n2 = (int)(n >>> 32); final int n3 = (int)n; if (n2 != 0) { if (((long)this.engineState[13] & 0xFFFFFFFFL) < ((long)n2 & 0xFFFFFFFFL)) { throw new IllegalStateException("attempt to reduce counter past zero."); } final int[] engineState = this.engineState; final int n4 = 13; engineState[n4] -= n2; } if (((long)this.engineState[12] & 0xFFFFFFFFL) >= ((long)n3 & 0xFFFFFFFFL)) { final int[] engineState2 = this.engineState; final int n5 = 12; engineState2[n5] -= n3; } else { if (this.engineState[13] == 0) { throw new IllegalStateException("attempt to reduce counter past zero."); } final int[] engineState3 = this.engineState; final int n6 = 13; --engineState3[n6]; final int[] engineState4 = this.engineState; final int n7 = 12; engineState4[n7] -= n3; } } @Override protected void retreatCounter() { if (this.engineState[12] == 0 && this.engineState[13] == 0) { throw new IllegalStateException("attempt to reduce counter past zero."); } final int[] engineState = this.engineState; final int n = 12; if (--engineState[n] == -1) { final int[] engineState2 = this.engineState; final int n2 = 13; --engineState2[n2]; } } @Override protected long getCounter() { return (long)this.engineState[13] << 32 | ((long)this.engineState[12] & 0xFFFFFFFFL); } @Override protected void resetCounter() { this.engineState[12] = (this.engineState[13] = 0); } @Override protected void setKey(final byte[] array, final byte[] array2) { if (array != null) { if (array.length != 16 && array.length != 32) { throw new IllegalArgumentException(this.getAlgorithmName() + " requires 128 bit or 256 bit key"); } this.packTauOrSigma(array.length, this.engineState, 0); Pack.littleEndianToInt(array, 0, this.engineState, 4, 4); Pack.littleEndianToInt(array, array.length - 16, this.engineState, 8, 4); } Pack.littleEndianToInt(array2, 0, this.engineState, 14, 2); } @Override protected void generateKeyStream(final byte[] array) { chachaCore(this.rounds, this.engineState, this.x); Pack.intToLittleEndian(this.x, array, 0); } public static void chachaCore(final int n, final int[] array, final int[] array2) { if (array.length != 16) { throw new IllegalArgumentException(); } if (array2.length != 16) { throw new IllegalArgumentException(); } if (n % 2 != 0) { throw new IllegalArgumentException("Number of rounds must be even"); } int n2 = array[0]; int n3 = array[1]; int n4 = array[2]; int n5 = array[3]; int rotateLeft = array[4]; int rotateLeft2 = array[5]; int rotateLeft3 = array[6]; int rotateLeft4 = array[7]; int n6 = array[8]; int n7 = array[9]; int n8 = array[10]; int n9 = array[11]; int rotateLeft5 = array[12]; int rotateLeft6 = array[13]; int rotateLeft7 = array[14]; int rotateLeft8 = array[15]; for (int i = n; i > 0; i -= 2) { final int n10 = n2 + rotateLeft; final int rotateLeft9 = Integers.rotateLeft(rotateLeft5 ^ n10, 16); final int n11 = n6 + rotateLeft9; final int rotateLeft10 = Integers.rotateLeft(rotateLeft ^ n11, 12); final int n12 = n10 + rotateLeft10; final int rotateLeft11 = Integers.rotateLeft(rotateLeft9 ^ n12, 8); final int n13 = n11 + rotateLeft11; final int rotateLeft12 = Integers.rotateLeft(rotateLeft10 ^ n13, 7); final int n14 = n3 + rotateLeft2; final int rotateLeft13 = Integers.rotateLeft(rotateLeft6 ^ n14, 16); final int n15 = n7 + rotateLeft13; final int rotateLeft14 = Integers.rotateLeft(rotateLeft2 ^ n15, 12); final int n16 = n14 + rotateLeft14; final int rotateLeft15 = Integers.rotateLeft(rotateLeft13 ^ n16, 8); final int n17 = n15 + rotateLeft15; final int rotateLeft16 = Integers.rotateLeft(rotateLeft14 ^ n17, 7); final int n18 = n4 + rotateLeft3; final int rotateLeft17 = Integers.rotateLeft(rotateLeft7 ^ n18, 16); final int n19 = n8 + rotateLeft17; final int rotateLeft18 = Integers.rotateLeft(rotateLeft3 ^ n19, 12); final int n20 = n18 + rotateLeft18; final int rotateLeft19 = Integers.rotateLeft(rotateLeft17 ^ n20, 8); final int n21 = n19 + rotateLeft19; final int rotateLeft20 = Integers.rotateLeft(rotateLeft18 ^ n21, 7); final int n22 = n5 + rotateLeft4; final int rotateLeft21 = Integers.rotateLeft(rotateLeft8 ^ n22, 16); final int n23 = n9 + rotateLeft21; final int rotateLeft22 = Integers.rotateLeft(rotateLeft4 ^ n23, 12); final int n24 = n22 + rotateLeft22; final int rotateLeft23 = Integers.rotateLeft(rotateLeft21 ^ n24, 8); final int n25 = n23 + rotateLeft23; final int rotateLeft24 = Integers.rotateLeft(rotateLeft22 ^ n25, 7); final int n26 = n12 + rotateLeft16; final int rotateLeft25 = Integers.rotateLeft(rotateLeft23 ^ n26, 16); final int n27 = n21 + rotateLeft25; final int rotateLeft26 = Integers.rotateLeft(rotateLeft16 ^ n27, 12); n2 = n26 + rotateLeft26; rotateLeft8 = Integers.rotateLeft(rotateLeft25 ^ n2, 8); n8 = n27 + rotateLeft8; rotateLeft2 = Integers.rotateLeft(rotateLeft26 ^ n8, 7); final int n28 = n16 + rotateLeft20; final int rotateLeft27 = Integers.rotateLeft(rotateLeft11 ^ n28, 16); final int n29 = n25 + rotateLeft27; final int rotateLeft28 = Integers.rotateLeft(rotateLeft20 ^ n29, 12); n3 = n28 + rotateLeft28; rotateLeft5 = Integers.rotateLeft(rotateLeft27 ^ n3, 8); n9 = n29 + rotateLeft5; rotateLeft3 = Integers.rotateLeft(rotateLeft28 ^ n9, 7); final int n30 = n20 + rotateLeft24; final int rotateLeft29 = Integers.rotateLeft(rotateLeft15 ^ n30, 16); final int n31 = n13 + rotateLeft29; final int rotateLeft30 = Integers.rotateLeft(rotateLeft24 ^ n31, 12); n4 = n30 + rotateLeft30; rotateLeft6 = Integers.rotateLeft(rotateLeft29 ^ n4, 8); n6 = n31 + rotateLeft6; rotateLeft4 = Integers.rotateLeft(rotateLeft30 ^ n6, 7); final int n32 = n24 + rotateLeft12; final int rotateLeft31 = Integers.rotateLeft(rotateLeft19 ^ n32, 16); final int n33 = n17 + rotateLeft31; final int rotateLeft32 = Integers.rotateLeft(rotateLeft12 ^ n33, 12); n5 = n32 + rotateLeft32; rotateLeft7 = Integers.rotateLeft(rotateLeft31 ^ n5, 8); n7 = n33 + rotateLeft7; rotateLeft = Integers.rotateLeft(rotateLeft32 ^ n7, 7); } array2[0] = n2 + array[0]; array2[1] = n3 + array[1]; array2[2] = n4 + array[2]; array2[3] = n5 + array[3]; array2[4] = rotateLeft + array[4]; array2[5] = rotateLeft2 + array[5]; array2[6] = rotateLeft3 + array[6]; array2[7] = rotateLeft4 + array[7]; array2[8] = n6 + array[8]; array2[9] = n7 + array[9]; array2[10] = n8 + array[10]; array2[11] = n9 + array[11]; array2[12] = rotateLeft5 + array[12]; array2[13] = rotateLeft6 + array[13]; array2[14] = rotateLeft7 + array[14]; array2[15] = rotateLeft8 + array[15]; } }