def runTest(self):
data = b"0123"
key = b"9" * 32
nonce = b"t" * 8
# Encryption
data_mv = memoryview(bytearray(data))
key_mv = memoryview(bytearray(key))
nonce_mv = memoryview(bytearray(nonce))
cipher1 = ChaCha20.new(key=key, nonce=nonce)
ct = cipher1.encrypt(data)
cipher2 = ChaCha20.new(key=key_mv, nonce=nonce_mv)
key_mv[:1] = b'\xFF'
nonce_mv[:1] = b'\xFF'
ct_test = cipher2.encrypt(data_mv)
self.assertEqual(ct, ct_test)
self.assertEqual(cipher1.nonce, cipher2.nonce)
# Decryption
key_mv = memoryview(bytearray(key))
nonce_mv = memoryview(bytearray(nonce))
ct_mv = memoryview(bytearray(ct))
cipher3 = ChaCha20.new(key=key_mv, nonce=nonce_mv)
key_mv[:1] = b'\xFF'
nonce_mv[:1] = b'\xFF'
pt_test = cipher3.decrypt(ct_mv)
self.assertEqual(data, pt_test)
def test_round_trip(self):
pt = b("A") * 1024
c1 = ChaCha20.new(key=b("5") * 32, nonce=b("6") * 8)
c2 = ChaCha20.new(key=b("5") * 32, nonce=b("6") * 8)
ct = c1.encrypt(pt)
self.assertEqual(c2.decrypt(ct), pt)
self.assertEqual(c1.encrypt(b("")), b(""))
self.assertEqual(c2.decrypt(b("")), b(""))
def test_eiter_encrypt_or_decrypt(self):
"""Verify that a cipher cannot be used for both decrypting and encrypting"""
c1 = ChaCha20.new(key=b("5") * 32, nonce=b("6") * 8)
c1.encrypt(b("8"))
self.assertRaises(TypeError, c1.decrypt, b("9"))
c2 = ChaCha20.new(key=b("5") * 32, nonce=b("6") * 8)
c2.decrypt(b("8"))
self.assertRaises(TypeError, c2.encrypt, b("9"))
def test_seek(self):
cipher1 = ChaCha20.new(key=b("9") * 32, nonce=b("e") * 8)
offset = 64 * 900 + 7
pt = b("1") * 64
cipher1.encrypt(b("0") * offset)
ct1 = cipher1.encrypt(pt)
cipher2 = ChaCha20.new(key=b("9") * 32, nonce=b("e") * 8)
cipher2.seek(offset)
ct2 = cipher2.encrypt(pt)
self.assertEqual(ct1, ct2)
def test_streaming(self):
"""Verify that an arbitrary number of bytes can be encrypted/decrypted"""
from crypto.Hash import SHA1
segments = (1, 3, 5, 7, 11, 17, 23)
total = sum(segments)
pt = b("")
while len(pt) < total:
pt += SHA1.new(pt).digest()
cipher1 = ChaCha20.new(key=b("7") * 32, nonce=b("t") * 8)
ct = cipher1.encrypt(pt)
cipher2 = ChaCha20.new(key=b("7") * 32, nonce=b("t") * 8)
cipher3 = ChaCha20.new(key=b("7") * 32, nonce=b("t") * 8)
idx = 0
for segment in segments:
self.assertEqual(cipher2.decrypt(ct[idx:idx+segment]), pt[idx:idx+segment])
self.assertEqual(cipher3.encrypt(pt[idx:idx+segment]), ct[idx:idx+segment])
idx += segment
def test_seek_tv(self):
# Test Vector #4, A.1 from
# http://tools.ietf.org/html/draft-nir-cfrg-chacha20-poly1305-04
key = bchr(0) + bchr(255) + bchr(0) * 30
nonce = bchr(0) * 8
cipher = ChaCha20.new(key=key, nonce=nonce)
cipher.seek(64 * 2)
expected_key_stream = unhexlify(b(
"72d54dfbf12ec44b362692df94137f32"
"8fea8da73990265ec1bbbea1ae9af0ca"
"13b25aa26cb4a648cb9b9d1be65b2c09"
"24a66c54d545ec1b7374f4872e99f096"
))
ct = cipher.encrypt(bchr(0) * len(expected_key_stream))
self.assertEqual(expected_key_stream, ct)
def test_default_nonce(self):
cipher1 = ChaCha20.new(key=bchr(1) * 32)
cipher2 = ChaCha20.new(key=bchr(1) * 32)
self.assertEqual(len(cipher1.nonce), 8)
self.assertNotEqual(cipher1.nonce, cipher2.nonce)
def test_new_positive(self):
cipher = ChaCha20.new(key=b("0")*32, nonce=b"0"*8)
self.assertEqual(cipher.nonce, b"0" * 8)
cipher = ChaCha20.new(key=b("0")*32, nonce=b"0"*12)
self.assertEqual(cipher.nonce, b"0" * 12)
def runTest(self):
for (key, nonce, stream) in self.tv:
c = ChaCha20.new(key=unhexlify(b(key)), nonce=unhexlify(b(nonce)))
ct = unhexlify(b(stream))
pt = b("\x00") * len(ct)
self.assertEqual(c.encrypt(pt), ct)
def test_rfc7539(self):
# from https://tools.ietf.org/html/rfc7539 Annex A.1
# Each item is: key, nonce, block #, plaintext, ciphertext
tvs = [
# Test Vector #1
(
"00"*32,
"00"*12,
0,
"00"*16*4,
"76b8e0ada0f13d90405d6ae55386bd28"
"bdd219b8a08ded1aa836efcc8b770dc7"
"da41597c5157488d7724e03fb8d84a37"
"6a43b8f41518a11cc387b669b2ee6586"
),
# Test Vector #2
(
"00"*31 + "01",
"00"*11 + "02",
1,
"416e79207375626d697373696f6e2074"
"6f20746865204945544620696e74656e"
"6465642062792074686520436f6e7472"
"696275746f7220666f72207075626c69"
"636174696f6e20617320616c6c206f72"
"2070617274206f6620616e2049455446"
"20496e7465726e65742d447261667420"
"6f722052464320616e6420616e792073"
"746174656d656e74206d616465207769"
"7468696e2074686520636f6e74657874"
"206f6620616e20494554462061637469"
"7669747920697320636f6e7369646572"
"656420616e20224945544620436f6e74"
"7269627574696f6e222e205375636820"
"73746174656d656e747320696e636c75"
"6465206f72616c2073746174656d656e"
"747320696e2049455446207365737369"
"6f6e732c2061732077656c6c20617320"
"7772697474656e20616e6420656c6563"
"74726f6e696320636f6d6d756e696361"
"74696f6e73206d61646520617420616e"
"792074696d65206f7220706c6163652c"
"20776869636820617265206164647265"
"7373656420746f",
"a3fbf07df3fa2fde4f376ca23e827370"
"41605d9f4f4f57bd8cff2c1d4b7955ec"
"2a97948bd3722915c8f3d337f7d37005"
"0e9e96d647b7c39f56e031ca5eb6250d"
"4042e02785ececfa4b4bb5e8ead0440e"
"20b6e8db09d881a7c6132f420e527950"
"42bdfa7773d8a9051447b3291ce1411c"
"680465552aa6c405b7764d5e87bea85a"
"d00f8449ed8f72d0d662ab052691ca66"
"424bc86d2df80ea41f43abf937d3259d"
"c4b2d0dfb48a6c9139ddd7f76966e928"
"e635553ba76c5c879d7b35d49eb2e62b"
"0871cdac638939e25e8a1e0ef9d5280f"
"a8ca328b351c3c765989cbcf3daa8b6c"
"cc3aaf9f3979c92b3720fc88dc95ed84"
"a1be059c6499b9fda236e7e818b04b0b"
"c39c1e876b193bfe5569753f88128cc0"
"8aaa9b63d1a16f80ef2554d7189c411f"
"5869ca52c5b83fa36ff216b9c1d30062"
"bebcfd2dc5bce0911934fda79a86f6e6"
"98ced759c3ff9b6477338f3da4f9cd85"
"14ea9982ccafb341b2384dd902f3d1ab"
"7ac61dd29c6f21ba5b862f3730e37cfd"
"c4fd806c22f221"
),
# Test Vector #3
(
"1c9240a5eb55d38af333888604f6b5f0"
"473917c1402b80099dca5cbc207075c0",
"00"*11 + "02",
42,
"2754776173206272696c6c69672c2061"
"6e642074686520736c6974687920746f"
"7665730a446964206779726520616e64"
"2067696d626c6520696e207468652077"
"6162653a0a416c6c206d696d73792077"
"6572652074686520626f726f676f7665"
"732c0a416e6420746865206d6f6d6520"
"7261746873206f757467726162652e",
"62e6347f95ed87a45ffae7426f27a1df"
"5fb69110044c0d73118effa95b01e5cf"
"166d3df2d721caf9b21e5fb14c616871"
"fd84c54f9d65b283196c7fe4f60553eb"
"f39c6402c42234e32a356b3e764312a6"
"1a5532055716ead6962568f87d3f3f77"
"04c6a8d1bcd1bf4d50d6154b6da731b1"
"87b58dfd728afa36757a797ac188d1"
)
]
for tv in tvs:
key = unhexlify(tv[0])
nonce = unhexlify(tv[1])
offset = tv[2] * 64
pt = unhexlify(tv[3])
ct_expect = unhexlify(tv[4])
cipher = ChaCha20.new(key=key, nonce=nonce)
if offset != 0:
cipher.seek(offset)
ct = cipher.encrypt(pt)
assert(ct == ct_expect)