You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
63 lines
2.0 KiB
63 lines
2.0 KiB
#!/usr/bin/env python3 |
|
# Copyright (c) 2016-2018 The Bitcoin Core developers |
|
# Distributed under the MIT software license, see the accompanying |
|
# file COPYING or http://www.opensource.org/licenses/mit-license.php. |
|
"""Specialized SipHash-2-4 implementations. |
|
|
|
This implements SipHash-2-4 for 256-bit integers. |
|
""" |
|
|
|
def rotl64(n, b): |
|
return n >> (64 - b) | (n & ((1 << (64 - b)) - 1)) << b |
|
|
|
def siphash_round(v0, v1, v2, v3): |
|
v0 = (v0 + v1) & ((1 << 64) - 1) |
|
v1 = rotl64(v1, 13) |
|
v1 ^= v0 |
|
v0 = rotl64(v0, 32) |
|
v2 = (v2 + v3) & ((1 << 64) - 1) |
|
v3 = rotl64(v3, 16) |
|
v3 ^= v2 |
|
v0 = (v0 + v3) & ((1 << 64) - 1) |
|
v3 = rotl64(v3, 21) |
|
v3 ^= v0 |
|
v2 = (v2 + v1) & ((1 << 64) - 1) |
|
v1 = rotl64(v1, 17) |
|
v1 ^= v2 |
|
v2 = rotl64(v2, 32) |
|
return (v0, v1, v2, v3) |
|
|
|
def siphash256(k0, k1, h): |
|
n0 = h & ((1 << 64) - 1) |
|
n1 = (h >> 64) & ((1 << 64) - 1) |
|
n2 = (h >> 128) & ((1 << 64) - 1) |
|
n3 = (h >> 192) & ((1 << 64) - 1) |
|
v0 = 0x736f6d6570736575 ^ k0 |
|
v1 = 0x646f72616e646f6d ^ k1 |
|
v2 = 0x6c7967656e657261 ^ k0 |
|
v3 = 0x7465646279746573 ^ k1 ^ n0 |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0 ^= n0 |
|
v3 ^= n1 |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0 ^= n1 |
|
v3 ^= n2 |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0 ^= n2 |
|
v3 ^= n3 |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0 ^= n3 |
|
v3 ^= 0x2000000000000000 |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0 ^= 0x2000000000000000 |
|
v2 ^= 0xFF |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
v0, v1, v2, v3 = siphash_round(v0, v1, v2, v3) |
|
return v0 ^ v1 ^ v2 ^ v3
|
|
|