1  # Copyright (c) 2021 Pieter Wuille
  2  # Distributed under the MIT software license, see the accompanying
  3  # file COPYING or http://www.opensource.org/licenses/mit-license.php.
  4  """Test-only pure Python RIPEMD160 implementation."""
  5  
  6  import unittest
  7  
  8  # Message schedule indexes for the left path.
  9  ML = [
 10      0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15,
 11      7, 4, 13, 1, 10, 6, 15, 3, 12, 0, 9, 5, 2, 14, 11, 8,
 12      3, 10, 14, 4, 9, 15, 8, 1, 2, 7, 0, 6, 13, 11, 5, 12,
 13      1, 9, 11, 10, 0, 8, 12, 4, 13, 3, 7, 15, 14, 5, 6, 2,
 14      4, 0, 5, 9, 7, 12, 2, 10, 14, 1, 3, 8, 11, 6, 15, 13
 15  ]
 16  
 17  # Message schedule indexes for the right path.
 18  MR = [
 19      5, 14, 7, 0, 9, 2, 11, 4, 13, 6, 15, 8, 1, 10, 3, 12,
 20      6, 11, 3, 7, 0, 13, 5, 10, 14, 15, 8, 12, 4, 9, 1, 2,
 21      15, 5, 1, 3, 7, 14, 6, 9, 11, 8, 12, 2, 10, 0, 4, 13,
 22      8, 6, 4, 1, 3, 11, 15, 0, 5, 12, 2, 13, 9, 7, 10, 14,
 23      12, 15, 10, 4, 1, 5, 8, 7, 6, 2, 13, 14, 0, 3, 9, 11
 24  ]
 25  
 26  # Rotation counts for the left path.
 27  RL = [
 28      11, 14, 15, 12, 5, 8, 7, 9, 11, 13, 14, 15, 6, 7, 9, 8,
 29      7, 6, 8, 13, 11, 9, 7, 15, 7, 12, 15, 9, 11, 7, 13, 12,
 30      11, 13, 6, 7, 14, 9, 13, 15, 14, 8, 13, 6, 5, 12, 7, 5,
 31      11, 12, 14, 15, 14, 15, 9, 8, 9, 14, 5, 6, 8, 6, 5, 12,
 32      9, 15, 5, 11, 6, 8, 13, 12, 5, 12, 13, 14, 11, 8, 5, 6
 33  ]
 34  
 35  # Rotation counts for the right path.
 36  RR = [
 37      8, 9, 9, 11, 13, 15, 15, 5, 7, 7, 8, 11, 14, 14, 12, 6,
 38      9, 13, 15, 7, 12, 8, 9, 11, 7, 7, 12, 7, 6, 15, 13, 11,
 39      9, 7, 15, 11, 8, 6, 6, 14, 12, 13, 5, 14, 13, 13, 7, 5,
 40      15, 5, 8, 11, 14, 14, 6, 14, 6, 9, 12, 9, 12, 5, 15, 8,
 41      8, 5, 12, 9, 12, 5, 14, 6, 8, 13, 6, 5, 15, 13, 11, 11
 42  ]
 43  
 44  # K constants for the left path.
 45  KL = [0, 0x5a827999, 0x6ed9eba1, 0x8f1bbcdc, 0xa953fd4e]
 46  
 47  # K constants for the right path.
 48  KR = [0x50a28be6, 0x5c4dd124, 0x6d703ef3, 0x7a6d76e9, 0]
 49  
 50  
 51  def fi(x, y, z, i):
 52      """The f1, f2, f3, f4, and f5 functions from the specification."""
 53      if i == 0:
 54          return x ^ y ^ z
 55      elif i == 1:
 56          return (x & y) | (~x & z)
 57      elif i == 2:
 58          return (x | ~y) ^ z
 59      elif i == 3:
 60          return (x & z) | (y & ~z)
 61      elif i == 4:
 62          return x ^ (y | ~z)
 63      else:
 64          assert False
 65  
 66  
 67  def rol(x, i):
 68      """Rotate the bottom 32 bits of x left by i bits."""
 69      return ((x << i) | ((x & 0xffffffff) >> (32 - i))) & 0xffffffff
 70  
 71  
 72  def compress(h0, h1, h2, h3, h4, block):
 73      """Compress state (h0, h1, h2, h3, h4) with block."""
 74      # Left path variables.
 75      al, bl, cl, dl, el = h0, h1, h2, h3, h4
 76      # Right path variables.
 77      ar, br, cr, dr, er = h0, h1, h2, h3, h4
 78      # Message variables.
 79      x = [int.from_bytes(block[4*i:4*(i+1)], 'little') for i in range(16)]
 80  
 81      # Iterate over the 80 rounds of the compression.
 82      for j in range(80):
 83          rnd = j >> 4
 84          # Perform left side of the transformation.
 85          al = rol(al + fi(bl, cl, dl, rnd) + x[ML[j]] + KL[rnd], RL[j]) + el
 86          al, bl, cl, dl, el = el, al, bl, rol(cl, 10), dl
 87          # Perform right side of the transformation.
 88          ar = rol(ar + fi(br, cr, dr, 4 - rnd) + x[MR[j]] + KR[rnd], RR[j]) + er
 89          ar, br, cr, dr, er = er, ar, br, rol(cr, 10), dr
 90  
 91      # Compose old state, left transform, and right transform into new state.
 92      return h1 + cl + dr, h2 + dl + er, h3 + el + ar, h4 + al + br, h0 + bl + cr
 93  
 94  
 95  def ripemd160(data):
 96      """Compute the RIPEMD-160 hash of data."""
 97      # Initialize state.
 98      state = (0x67452301, 0xefcdab89, 0x98badcfe, 0x10325476, 0xc3d2e1f0)
 99      # Process full 64-byte blocks in the input.
100      for b in range(len(data) >> 6):
101          state = compress(*state, data[64*b:64*(b+1)])
102      # Construct final blocks (with padding and size).
103      pad = b"\x80" + b"\x00" * ((119 - len(data)) & 63)
104      fin = data[len(data) & ~63:] + pad + (8 * len(data)).to_bytes(8, 'little')
105      # Process final blocks.
106      for b in range(len(fin) >> 6):
107          state = compress(*state, fin[64*b:64*(b+1)])
108      # Produce output.
109      return b"".join((h & 0xffffffff).to_bytes(4, 'little') for h in state)
110  
111  
112  class TestFrameworkKey(unittest.TestCase):
113      def test_ripemd160(self):
114          """RIPEMD-160 test vectors."""
115          # See https://homes.esat.kuleuven.be/~bosselae/ripemd160.html
116          for msg, hexout in [
117              (b"", "9c1185a5c5e9fc54612808977ee8f548b2258d31"),
118              (b"a", "0bdc9d2d256b3ee9daae347be6f4dc835a467ffe"),
119              (b"abc", "8eb208f7e05d987a9b044a8e98c6b087f15a0bfc"),
120              (b"message digest", "5d0689ef49d2fae572b881b123a85ffa21595f36"),
121              (b"abcdefghijklmnopqrstuvwxyz",
122                  "f71c27109c692c1b56bbdceb5b9d2865b3708dbc"),
123              (b"abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq",
124                  "12a053384a9c0c88e405a06c27dcf49ada62eb2b"),
125              (b"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789",
126                  "b0e20b6e3116640286ed3a87a5713079b21f5189"),
127              (b"1234567890" * 8, "9b752e45573d4b39f4dbd3323cab82bf63326bfb"),
128              (b"a" * 1000000, "52783243c1697bdbe16d37f97f68f08325dc1528")
129          ]:
130              self.assertEqual(ripemd160(msg).hex(), hexout)