Create verushash.py

Author: HugoXOX3

hashes/verushash.py

@@ -0,0 +1,136 @@
+import hashlib
+
+def verushash(data):
+    """
+    Compute VerusHash of the input data.
+    VerusHash alternates between SHA-256 and Keccak-256 in a specific sequence.
+
+    Args:
+        data (bytes): The input data to be hashed.
+
+    Returns:
+        bytes: The VerusHash result as a byte string.
+    """
+    def sha256(data):
+        """Compute SHA-256 hash of the input data using hashlib."""
+        return hashlib.sha256(data).digest()
+
+    def keccak256(data):
+        """Compute Keccak-256 hash of the input data using a custom implementation."""
+        # Keccak-256 parameters
+        ROUNDS = 24
+        RATE = 1088  # Rate in bits (1600 - 2*256)
+        CAPACITY = 512  # Capacity in bits (2*256)
+        STATE_SIZE = 1600  # State size in bits (5x5x64)
+
+        # Padding
+        PADDING = 0x06
+        DELIMITER = 0x80
+
+        # Initialize the state
+        state = [0] * (STATE_SIZE // 8)  # State in bytes
+
+        # Absorb phase
+        block_size = RATE // 8
+        padded_data = data + bytes([PADDING]) + bytes([0] * (block_size - (len(data) + 1) % block_size))
+        padded_data += bytes([DELIMITER])
+
+        for i in range(0, len(padded_data), block_size):
+            block = padded_data[i:i + block_size]
+            for j in range(len(block)):
+                state[j] ^= block[j]
+            state = keccak_f(state)
+
+        # Squeeze phase
+        output = bytearray()
+        while len(output) < 32:  # 256 bits = 32 bytes
+            output.extend(state[:block_size])
+            state = keccak_f(state)
+
+        return bytes(output[:32])
+
+    def keccak_f(state):
+        """Keccak-f permutation function."""
+        # Convert state to a 5x5x64 array
+        lanes = [[0] * 5 for _ in range(5)]
+        for x in range(5):
+            for y in range(5):
+                index = 8 * (x + 5 * y)
+                lane = int.from_bytes(state[index:index + 8], byteorder='little')
+                lanes[x][y] = lane
+
+        # Perform 24 rounds of Keccak-f
+        for round in range(ROUNDS):
+            lanes = keccak_round(lanes, round)
+
+        # Convert lanes back to bytes
+        state = bytearray()
+        for y in range(5):
+            for x in range(5):
+                state.extend(lanes[x][y].to_bytes(8, byteorder='little'))
+
+        return state
+
+    def keccak_round(lanes, round):
+        """Perform one round of Keccak-f."""
+        # Theta step
+        c = [lanes[x][0] ^ lanes[x][1] ^ lanes[x][2] ^ lanes[x][3] ^ lanes[x][4] for x in range(5)]
+        d = [c[(x - 1) % 5] ^ ((c[(x + 1) % 5] << 1 | c[(x + 1) % 5] >> 63) for x in range(5)]
+        for x in range(5):
+            for y in range(5):
+                lanes[x][y] ^= d[x]
+
+        # Rho and Pi steps
+        x, y = 1, 0
+        current = lanes[x][y]
+        for t in range(24):
+            x, y = y, (2 * x + 3 * y) % 5
+            current, lanes[x][y] = lanes[x][y], (current << ((t + 1) * (t + 2) // 2) | current >> (64 - ((t + 1) * (t + 2) // 2))
+
+        # Chi step
+        for y in range(5):
+            t = [lanes[x][y] for x in range(5)]
+            for x in range(5):
+                lanes[x][y] = t[x] ^ (~t[(x + 1) % 5] & t[(x + 2) % 5])
+
+        # Iota step
+        lanes[0][0] ^= ROUND_CONSTANTS[round]
+
+        return lanes
+
+    # Round constants for Keccak-f
+    ROUND_CONSTANTS = [
+        0x0000000000000001, 0x0000000000008082, 0x800000000000808A,
+        0x8000000080008000, 0x000000000000808B, 0x0000000080000001,
+        0x8000000080008081, 0x8000000000008009, 0x000000000000008A,
+        0x0000000000000088, 0x0000000080008009, 0x000000008000000A,
+        0x000000008000808B, 0x800000000000008B, 0x8000000000008089,
+        0x8000000000008003, 0x8000000000008002, 0x8000000000000080,
+        0x000000000000800A, 0x800000008000000A, 0x8000000080008081,
+        0x8000000000008080, 0x0000000080000001, 0x8000000080008008
+    ]
+
+    # Step 1: Compute SHA-256 of the input data
+    hash1 = sha256(data)
+
+    # Step 2: Compute Keccak-256 of the SHA-256 result
+    hash2 = keccak256(hash1)
+
+    # Step 3: Compute SHA-256 of the Keccak-256 result
+    hash3 = sha256(hash2)
+
+    # Step 4: Compute Keccak-256 of the final SHA-256 result
+    final_hash = keccak256(hash3)
+
+    return final_hash
+
+# Example usage
+if __name__ == "__main__":
+    # Input data (can be a block header or any other data)
+    input_data = b"Hello, VerusHash!"
+
+    # Compute VerusHash
+    result = verushash(input_data)
+
+    # Print the result as a hexadecimal string
+    print("VerusHash:", result.hex())