def test_public_smoke_matches(random, seed, data):
"""Prepare a params struct, and make sure the UMASH function matches
our reference."""
params = FFI.new("struct umash_params[1]")
size = FFI.sizeof("struct umash_params")
assert size % 8 == 0
for i in range(size // 8):
FFI.cast("uint64_t *", params)[i] = random.getrandbits(64)
# Pseudorandom input should always succeed.
assert C.umash_params_prepare(params) == True
assert_idempotent(params)
expected0 = umash(
UmashKey(params[0].poly[0][1],
[params[0].oh[i] for i in range(OH_COUNT)]),
seed,
data,
secondary=False,
)
assert C.umash_full(params, seed, 0, data, len(data)) == expected0
expected1 = umash(
UmashKey(
params[0].poly[1][1],
[params[0].oh[i] for i in range(OH_COUNT)],
),
seed,
data,
secondary=True,
)
assert C.umash_full(params, seed, 1, data, len(data)) == expected1
def reference_value(self):
return umash(
UmashKey(
poly=self.multipliers[self.which],
ph=self.ph[self.which * C.UMASH_PH_TOEPLITZ_SHIFT:],
),
self.seed,
self.acc,
)
def test_public_umash_fprint(seed, multipliers, key, data):
"""Compare umash_fprint with two calls to the reference."""
expected = [
umash(UmashKey(poly=multipliers[0], oh=key[:-4]), seed, data),
umash(UmashKey(poly=multipliers[1], oh=key[4:]), seed, data),
]
n_bytes = len(data)
block = FFI.new("char[]", n_bytes)
FFI.memmove(block, data, n_bytes)
params = FFI.new("struct umash_params[1]")
for i, multiplier in enumerate(multipliers):
params[0].poly[i][0] = (multiplier**2) % FIELD
params[0].poly[i][1] = multiplier
for i, param in enumerate(key):
params[0].oh[i] = param
actual = C.umash_fprint(params, seed, block, n_bytes)
assert [actual.hash[0], actual.hash[1]] == expected
def reference_value(self):
return [
umash(
UmashKey(
poly=self.multipliers[which],
oh=self.oh[which * C.UMASH_OH_TOEPLITZ_SHIFT:],
),
self.seed,
self.acc,
) for which in range(2)
]
def test_umash_short(seed, key, data):
"""Compare umash_short with the reference."""
expected = umash(UmashKey(poly=0, oh=key), seed, data)
n_bytes = len(data)
block = FFI.new("char[]", n_bytes)
FFI.memmove(block, data, n_bytes)
params = FFI.new("struct umash_params[1]")
for i, param in enumerate(key):
params[0].oh[i] = param
assert C.umash_short(params[0].oh, seed, block, n_bytes) == expected
def test_public_umash_full_shifted(seed, multiplier, key, data):
"""Compare umash_full(which=1) with the reference."""
expected = umash(UmashKey(poly=multiplier, oh=key), seed, data)
n_bytes = len(data)
block = FFI.new("char[]", n_bytes)
FFI.memmove(block, data, n_bytes)
params = FFI.new("struct umash_params[1]")
params[0].poly[1][0] = (multiplier**2) % FIELD
params[0].poly[1][1] = multiplier
for i, param in enumerate(key):
params[0].oh[i + C.UMASH_OH_TOEPLITZ_SHIFT] = param
assert C.umash_full(params, seed, 1, block, n_bytes) == expected
def test_public_umash_full(seed, multiplier, key, data):
"""Compare umash_full with the reference."""
expected = umash(UmashKey(poly=multiplier, ph=key), seed, data)
n_bytes = len(data)
block = FFI.new("char[]", n_bytes)
FFI.memmove(block, data, n_bytes)
params = FFI.new("struct umash_params[1]")
params[0].poly[0][0] = (multiplier ** 2) % FIELD
params[0].poly[0][1] = multiplier
for i, param in enumerate(key):
params[0].ph[i] = param
assert C.umash_full(params, seed, 0, block, n_bytes) == expected
def test_umash_medium(seed, multiplier, key, data):
"""Compare umash_medium with the reference."""
expected = umash(UmashKey(poly=multiplier, ph=key), seed, data)
n_bytes = len(data)
block = FFI.new("char[]", n_bytes)
FFI.memmove(block, data, n_bytes)
poly = FFI.new("uint64_t[2]")
poly[0] = (multiplier**2) % FIELD
poly[1] = multiplier
params = FFI.new("struct umash_params[1]")
for i, param in enumerate(key):
params[0].ph[i] = param
assert C.umash_medium(poly, params[0].ph, seed, block, n_bytes) == expected
def test_umash_long_repeat(seed, multiplier, key, data):
"""Compare umash_long on repeated strings with the reference."""
expected = umash(UmashKey(poly=multiplier, oh=key), seed, data, secondary=False)
note(len(data))
n_bytes = len(data)
block = FFI.new("char[]", n_bytes)
FFI.memmove(block, data, n_bytes)
poly = FFI.new("uint64_t[2]")
poly[0] = (multiplier ** 2) % FIELD
poly[1] = multiplier
params = FFI.new("struct umash_params[1]")
for i, param in enumerate(key):
params[0].oh[i] = param
assert C.umash_long(poly, params[0].oh, seed, block, n_bytes) == expected
