--- /dev/null
+### -*- mode: python, coding: utf-8 -*-
+###
+### Test symmetric algorithms
+###
+### (c) 2019 Straylight/Edgeware
+###
+
+###----- Licensing notice ---------------------------------------------------
+###
+### This file is part of the Python interface to Catacomb.
+###
+### Catacomb/Python is free software: you can redistribute it and/or
+### modify it under the terms of the GNU General Public License as
+### published by the Free Software Foundation; either version 2 of the
+### License, or (at your option) any later version.
+###
+### Catacomb/Python is distributed in the hope that it will be useful, but
+### WITHOUT ANY WARRANTY; without even the implied warranty of
+### MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+### General Public License for more details.
+###
+### You should have received a copy of the GNU General Public License
+### along with Catacomb/Python. If not, write to the Free Software
+### Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,
+### USA.
+
+###--------------------------------------------------------------------------
+### Imported modules.
+
+import catacomb as C
+import unittest as U
+import testutils as T
+
+###--------------------------------------------------------------------------
+### Utilities.
+
+def bad_key_size(ksz):
+ if isinstance(ksz, C.KeySZAny): return None
+ elif isinstance(ksz, C.KeySZRange):
+ if ksz.mod != 1: return ksz.min + 1
+ elif ksz.max != 0: return ksz.max + 1
+ elif ksz.min != 0: return ksz.min - 1
+ else: return None
+ elif isinstance(ksz, C.KeySZSet):
+ for sz in sorted(ksz.set):
+ if sz + 1 not in ksz.set: return sz + 1
+ assert False, "That should have worked."
+ else:
+ return None
+
+def different_key_size(ksz, sz):
+ if isinstance(ksz, C.KeySZAny): return sz + 1
+ elif isinstance(ksz, C.KeySZRange):
+ if sz > ksz.min: return sz - ksz.mod
+ elif ksz.max == 0 or sz < ksz.max: return sz + ksz.mod
+ else: return None
+ elif isinstance(ksz, C.KeySZSet):
+ for sz1 in sorted(ksz.set):
+ if sz != sz1: return sz1
+ return None
+ else:
+ return None
+
+class HashBufferTestMixin (U.TestCase):
+ """Mixin class for testing all of the various `hash...' methods."""
+
+ def check_hashbuffer_hashn(me, w, bigendp, makefn, hashfn):
+ """Check `hashuN'."""
+
+ ## Check encoding an integer.
+ h0, donefn0 = makefn(w + 2)
+ hashfn(h0.hashu8(0x00), T.bytes_as_int(w, bigendp)).hashu8(w + 1)
+ h1, donefn1 = makefn(w + 2)
+ h1.hash(T.span(w + 2))
+ me.assertEqual(donefn0(), donefn1())
+
+ ## Check overflow detection.
+ h0, _ = makefn(w)
+ me.assertRaises((OverflowError, ValueError),
+ hashfn, h0, 1 << 8*w)
+
+ def check_hashbuffer_bufn(me, w, bigendp, makefn, hashfn):
+ """Check `hashbufN'."""
+
+ ## Go through a number of different sizes.
+ for n in [0, 1, 7, 8, 19, 255, 12345, 65535, 123456]:
+ if n >= 1 << 8*w: continue
+ h0, donefn0 = makefn(2 + w + n)
+ hashfn(h0.hashu8(0x00), T.span(n)).hashu8(0xff)
+ h1, donefn1 = makefn(2 + w + n)
+ h1.hash(T.prep_lenseq(w, n, bigendp, True))
+ me.assertEqual(donefn0(), donefn1())
+
+ ## Check blocks which are too large for the length prefix.
+ if w <= 3:
+ n = 1 << 8*w
+ h0, _ = makefn(w + n)
+ me.assertRaises((ValueError, OverflowError, TypeError),
+ hashfn, h0, C.ByteString.zero(n))
+
+ def check_hashbuffer(me, makefn):
+ """Test the various `hash...' methods."""
+
+ ## Check `hashuN'.
+ me.check_hashbuffer_hashn(1, True, makefn, lambda h, n: h.hashu8(n))
+ me.check_hashbuffer_hashn(2, True, makefn, lambda h, n: h.hashu16(n))
+ me.check_hashbuffer_hashn(2, True, makefn, lambda h, n: h.hashu16b(n))
+ me.check_hashbuffer_hashn(2, False, makefn, lambda h, n: h.hashu16l(n))
+ if hasattr(makefn(0)[0], "hashu24"):
+ me.check_hashbuffer_hashn(3, True, makefn, lambda h, n: h.hashu24(n))
+ me.check_hashbuffer_hashn(3, True, makefn, lambda h, n: h.hashu24b(n))
+ me.check_hashbuffer_hashn(3, False, makefn, lambda h, n: h.hashu24l(n))
+ me.check_hashbuffer_hashn(4, True, makefn, lambda h, n: h.hashu32(n))
+ me.check_hashbuffer_hashn(4, True, makefn, lambda h, n: h.hashu32b(n))
+ me.check_hashbuffer_hashn(4, False, makefn, lambda h, n: h.hashu32l(n))
+ if hasattr(makefn(0)[0], "hashu64"):
+ me.check_hashbuffer_hashn(8, True, makefn, lambda h, n: h.hashu64(n))
+ me.check_hashbuffer_hashn(8, True, makefn, lambda h, n: h.hashu64b(n))
+ me.check_hashbuffer_hashn(8, False, makefn, lambda h, n: h.hashu64l(n))
+
+ ## Check `hashbufN'.
+ me.check_hashbuffer_bufn(1, True, makefn, lambda h, x: h.hashbuf8(x))
+ me.check_hashbuffer_bufn(2, True, makefn, lambda h, x: h.hashbuf16(x))
+ me.check_hashbuffer_bufn(2, True, makefn, lambda h, x: h.hashbuf16b(x))
+ me.check_hashbuffer_bufn(2, False, makefn, lambda h, x: h.hashbuf16l(x))
+ if hasattr(makefn(0)[0], "hashbuf24"):
+ me.check_hashbuffer_bufn(3, True, makefn, lambda h, x: h.hashbuf24(x))
+ me.check_hashbuffer_bufn(3, True, makefn, lambda h, x: h.hashbuf24b(x))
+ me.check_hashbuffer_bufn(3, False, makefn, lambda h, x: h.hashbuf24l(x))
+ me.check_hashbuffer_bufn(4, True, makefn, lambda h, x: h.hashbuf32(x))
+ me.check_hashbuffer_bufn(4, True, makefn, lambda h, x: h.hashbuf32b(x))
+ me.check_hashbuffer_bufn(4, False, makefn, lambda h, x: h.hashbuf32l(x))
+ if hasattr(makefn(0)[0], "hashbuf64"):
+ me.check_hashbuffer_bufn(8, True, makefn, lambda h, x: h.hashbuf64(x))
+ me.check_hashbuffer_bufn(8, True, makefn, lambda h, x: h.hashbuf64b(x))
+ me.check_hashbuffer_bufn(8, False, makefn, lambda h, x: h.hashbuf64l(x))
+
+###--------------------------------------------------------------------------
+class TestKeysize (U.TestCase):
+
+ def test_any(me):
+
+ ## A typical one-byte spec.
+ ksz = C.seal.keysz
+ me.assertEqual(type(ksz), C.KeySZAny)
+ me.assertEqual(ksz.default, 20)
+ me.assertEqual(ksz.min, 0)
+ me.assertEqual(ksz.max, 0)
+ for n in [0, 12, 20, 5000]:
+ me.assertTrue(ksz.check(n))
+ me.assertEqual(ksz.best(n), n)
+
+ ## A typical two-byte spec. (No published algorithms actually /need/ a
+ ## two-byte key-size spec, but all of the HMAC variants use one anyway.)
+ ksz = C.sha256_hmac.keysz
+ me.assertEqual(type(ksz), C.KeySZAny)
+ me.assertEqual(ksz.default, 32)
+ me.assertEqual(ksz.min, 0)
+ me.assertEqual(ksz.max, 0)
+ for n in [0, 12, 20, 5000]:
+ me.assertTrue(ksz.check(n))
+ me.assertEqual(ksz.best(n), n)
+
+ ## Check construction.
+ ksz = C.KeySZAny(15)
+ me.assertEqual(ksz.default, 15)
+ me.assertEqual(ksz.min, 0)
+ me.assertEqual(ksz.max, 0)
+ me.assertRaises(ValueError, lambda: C.KeySZAny(-8))
+ me.assertEqual(C.KeySZAny(0).default, 0)
+
+ def test_set(me):
+ ## Note that no published algorithm uses a 16-bit `set' spec.
+
+ ## A typical spec.
+ ksz = C.salsa20.keysz
+ me.assertEqual(type(ksz), C.KeySZSet)
+ me.assertEqual(ksz.default, 32)
+ me.assertEqual(ksz.min, 10)
+ me.assertEqual(ksz.max, 32)
+ me.assertEqual(set(ksz.set), set([10, 16, 32]))
+ for x, best, pad in [(9, None, 10), (10, 10, 10), (11, 10, 16),
+ (15, 10, 16), (16, 16, 16), (17, 16, 32),
+ (31, 16, 32), (32, 32, 32), (33, 32, None)]:
+ if x == best == pad: me.assertTrue(ksz.check(x))
+ else: me.assertFalse(ksz.check(x))
+ if best is None: me.assertRaises(ValueError, ksz.best, x)
+ else: me.assertEqual(ksz.best(x), best)
+
+ ## Check construction.
+ ksz = C.KeySZSet(7)
+ me.assertEqual(ksz.default, 7)
+ me.assertEqual(set(ksz.set), set([7]))
+ me.assertEqual(ksz.min, 7)
+ me.assertEqual(ksz.max, 7)
+ ksz = C.KeySZSet(7, [3, 6, 9])
+ me.assertEqual(ksz.default, 7)
+ me.assertEqual(set(ksz.set), set([3, 6, 7, 9]))
+ me.assertEqual(ksz.min, 3)
+ me.assertEqual(ksz.max, 9)
+
+ def test_range(me):
+ ## Note that no published algorithm uses a 16-bit `range' spec, or an
+ ## unbounded `range'.
+
+ ## A typical spec.
+ ksz = C.rijndael.keysz
+ me.assertEqual(type(ksz), C.KeySZRange)
+ me.assertEqual(ksz.default, 32)
+ me.assertEqual(ksz.min, 4)
+ me.assertEqual(ksz.max, 32)
+ me.assertEqual(ksz.mod, 4)
+ for x, best in [(3, None), (4, 4), (5, 4),
+ (15, 12), (16, 16), (17, 16),
+ (31, 28), (32, 32), (33, 32)]:
+ if x == best: me.assertTrue(ksz.check(x))
+ else: me.assertFalse(ksz.check(x))
+ if best is None: me.assertRaises(ValueError, ksz.best, x)
+ else: me.assertEqual(ksz.best(x), best)
+
+ ## Check construction.
+ ksz = C.KeySZRange(28, 21, 35, 7)
+ me.assertEqual(ksz.default, 28)
+ me.assertEqual(ksz.min, 21)
+ me.assertEqual(ksz.max, 35)
+ me.assertEqual(ksz.mod, 7)
+ me.assertRaises(ValueError, C.KeySZRange, 29, 21, 35, 7)
+ me.assertRaises(ValueError, C.KeySZRange, 28, 20, 35, 7)
+ me.assertRaises(ValueError, C.KeySZRange, 28, 21, 34, 7)
+ me.assertRaises(ValueError, C.KeySZRange, 28, -7, 35, 7)
+ me.assertRaises(ValueError, C.KeySZRange, 28, 35, 21, 7)
+ me.assertRaises(ValueError, C.KeySZRange, 35, 21, 28, 7)
+ me.assertRaises(ValueError, C.KeySZRange, 21, 28, 35, 7)
+
+ def test_conversions(me):
+ me.assertEqual(C.KeySZ.fromec(256), 128)
+ me.assertEqual(C.KeySZ.fromschnorr(256), 128)
+ me.assertEqual(round(C.KeySZ.fromdl(2958.6875)), 128)
+ me.assertEqual(round(C.KeySZ.fromif(2958.6875)), 128)
+ me.assertEqual(C.KeySZ.toec(128), 256)
+ me.assertEqual(C.KeySZ.toschnorr(128), 256)
+ me.assertEqual(C.KeySZ.todl(128), 2958.6875)
+ me.assertEqual(C.KeySZ.toif(128), 2958.6875)
+
+###--------------------------------------------------------------------------
+class TestCipher (T.GenericTestMixin):
+ """Test basic symmetric ciphers."""
+
+ def _test_cipher(me, ccls):
+
+ ## Check the class properties.
+ me.assertEqual(type(ccls.name), str)
+ me.assertTrue(isinstance(ccls.keysz, C.KeySZ))
+ me.assertEqual(type(ccls.blksz), int)
+
+ ## Check round-tripping.
+ k = T.span(ccls.keysz.default)
+ iv = T.span(ccls.blksz)
+ m = T.span(253)
+ enc = ccls(k)
+ dec = ccls(k)
+ try: enc.setiv(iv)
+ except ValueError: can_setiv = False
+ else:
+ can_setiv = True
+ dec.setiv(iv)
+ c0 = enc.encrypt(m[0:57])
+ m0 = dec.decrypt(c0)
+ c1 = enc.encrypt(m[57:189])
+ m1 = dec.decrypt(c1)
+ try: enc.bdry()
+ except ValueError: can_bdry = False
+ else:
+ dec.bdry()
+ can_bdry = True
+ c2 = enc.encrypt(m[189:253])
+ m2 = dec.decrypt(c2)
+ me.assertEqual(len(c0) + len(c1) + len(c2), len(m))
+ me.assertEqual(m0, m[0:57])
+ me.assertEqual(m1, m[57:189])
+ me.assertEqual(m2, m[189:253])
+
+ ## Check the `enczero' and `deczero' methods.
+ c3 = enc.enczero(32)
+ me.assertEqual(dec.decrypt(c3), C.ByteString.zero(32))
+ m4 = dec.deczero(32)
+ me.assertEqual(enc.encrypt(m4), C.ByteString.zero(32))
+
+ ## Check that ciphers which support a `boundary' operation actually
+ ## need it.
+ if can_bdry:
+ dec = ccls(k)
+ if can_setiv: dec.setiv(iv)
+ m01 = dec.decrypt(c0 + c1)
+ me.assertEqual(m01, m[0:189])
+
+ ## Check that the boundary actually does something.
+ if can_bdry:
+ dec = ccls(k)
+ if can_setiv: dec.setiv(iv)
+ m012 = dec.decrypt(c0 + c1 + c2)
+ me.assertNotEqual(m012, m)
+
+ ## Check that bad key lengths are rejected.
+ badlen = bad_key_size(ccls.keysz)
+ if badlen is not None: me.assertRaises(ValueError, ccls, T.span(badlen))
+
+TestCipher.generate_testcases((name, C.gcciphers[name]) for name in
+ ["des-ecb", "rijndael-cbc", "twofish-cfb", "serpent-ofb",
+ "blowfish-counter", "rc4", "seal", "salsa20/8", "shake128-xof"])
+
+###--------------------------------------------------------------------------
+class BaseTestHash (HashBufferTestMixin):
+ """Base class for testing hash functions."""
+
+ def check_hash(me, hcls, need_bufsz = True):
+ """
+ Check hash class HCLS.
+
+ If NEED_BUFSZ is false, then don't insist that HCLS have working `bufsz',
+ `name', or `hashsz' attributes. This test is mostly reused for MACs,
+ which don't have these attributes.
+ """
+ ## Check the class properties.
+ if need_bufsz:
+ me.assertEqual(type(hcls.name), str)
+ me.assertEqual(type(hcls.bufsz), int)
+ me.assertEqual(type(hcls.hashsz), int)
+
+ ## Set some initial values.
+ m = T.span(131)
+ h = hcls().hash(m).done()
+
+ ## Check that hash length comes out right.
+ if need_bufsz: me.assertEqual(len(h), hcls.hashsz)
+
+ ## Check that we get the same answer if we split the message up.
+ me.assertEqual(h, hcls().hash(m[0:73]).hash(m[73:131]).done())
+
+ ## Check the `check' method.
+ me.assertTrue(hcls().hash(m).check(h))
+ me.assertFalse(hcls().hash(m).check(h ^ len(h)*C.bytes("aa")))
+
+ ## Check the menagerie of random hashing methods.
+ def mkhash(_):
+ h = hcls()
+ return h, h.done
+ me.check_hashbuffer(mkhash)
+
+class TestHash (BaseTestHash, T.GenericTestMixin):
+ """Test hash functions."""
+ def _test_hash(me, hcls): me.check_hash(hcls, need_bufsz = True)
+
+TestHash.generate_testcases((name, C.gchashes[name]) for name in
+ ["md5", "sha", "whirlpool", "sha256", "sha512/224", "sha3-384", "shake256",
+ "crc32"])
+
+###--------------------------------------------------------------------------
+class TestMessageAuthentication (BaseTestHash, T.GenericTestMixin):
+ """Test message authentication codes."""
+
+ def _test_mac(me, mcls):
+
+ ## Check the MAC properties.
+ me.assertEqual(type(mcls.name), str)
+ me.assertTrue(isinstance(mcls.keysz, C.KeySZ))
+ me.assertEqual(type(mcls.tagsz), int)
+
+ ## Test hashing.
+ k = T.span(mcls.keysz.default)
+ key = mcls(k)
+ me.check_hash(key, need_bufsz = False)
+
+ ## Check that bad key lengths are rejected.
+ badlen = bad_key_size(mcls.keysz)
+ if badlen is not None: me.assertRaises(ValueError, mcls, T.span(badlen))
+
+TestMessageAuthentication.generate_testcases \
+ ((name, C.gcmacs[name]) for name in
+ ["sha-hmac", "rijndael-cmac", "twofish-pmac1", "kmac128"])
+
+class TestPoly1305 (HashBufferTestMixin):
+ """Check the Poly1305 one-time message authentication function."""
+
+ def test_poly1305(me):
+
+ ## Check the MAC properties.
+ me.assertEqual(C.poly1305.name, "poly1305")
+ me.assertEqual(type(C.poly1305.keysz), C.KeySZSet)
+ me.assertEqual(C.poly1305.keysz.default, 16)
+ me.assertEqual(set(C.poly1305.keysz.set), set([16]))
+ me.assertEqual(C.poly1305.tagsz, 16)
+ me.assertEqual(C.poly1305.masksz, 16)
+
+ ## Set some initial values.
+ k = T.span(16)
+ u = T.span(64)[-16:]
+ m = T.span(149)
+ key = C.poly1305(k)
+ t = key(u).hash(m).done()
+
+ ## Check the key properties.
+ me.assertEqual(len(t), 16)
+
+ ## Check that we get the same answer if we split the message up.
+ me.assertEqual(t, key(u).hash(m[0:86]).hash(m[86:149]).done())
+
+ ## Check the `check' method.
+ me.assertTrue(key(u).hash(m).check(t))
+ me.assertFalse(key(u).hash(m).check(t ^ 16*C.bytes("cc")))
+
+ ## Check the menagerie of random hashing methods.
+ def mkhash(_):
+ h = key(u)
+ return h, h.done
+ me.check_hashbuffer(mkhash)
+
+ ## Check that we can't complete hashing without a mask.
+ me.assertRaises(ValueError, key().hash(m).done)
+
+ ## Check `concat'.
+ h0 = key().hash(m[0:96])
+ h1 = key().hash(m[96:117])
+ me.assertEqual(t, key(u).concat(h0, h1).hash(m[117:149]).done())
+ key1 = C.poly1305(k)
+ me.assertRaises(TypeError, key().concat, key1().hash(m[0:96]), h1)
+ me.assertRaises(TypeError, key().concat, h0, key1().hash(m[96:117]))
+ me.assertRaises(ValueError, key().concat, key().hash(m[0:93]), h1)
+
+###--------------------------------------------------------------------------
+class TestHLatin (U.TestCase):
+ """Test the `hsalsa20' and `hchacha20' functions."""
+
+ def test_hlatin(me):
+ kk = [T.span(sz) for sz in [32]]
+ n = T.span(16)
+ bad_k = T.span(18)
+ bad_n = T.span(13)
+ for fn in [C.hsalsa208_prf, C.hsalsa2012_prf, C.hsalsa20_prf,
+ C.hchacha8_prf, C.hchacha12_prf, C.hchacha20_prf]:
+ for k in kk:
+ h = fn(k, n)
+ me.assertEqual(len(h), 32)
+ me.assertRaises(ValueError, fn, bad_k, n)
+ me.assertRaises(ValueError, fn, k, bad_n)
+
+###--------------------------------------------------------------------------
+class TestKeccak (HashBufferTestMixin):
+ """Test the Keccak-p[1600, n] sponge function."""
+
+ def test_keccak(me):
+
+ ## Make a state and feed some stuff into it.
+ m0 = T.bin("some initial string")
+ m1 = T.bin("awesome follow-up string")
+ st0 = C.Keccak1600()
+ me.assertEqual(st0.nround, 24)
+ st0.mix(m0).step()
+
+ ## Make another step with a different round count.
+ st1 = C.Keccak1600(23)
+ st1.mix(m0).step()
+ me.assertNotEqual(st0.extract(32), st1.extract(32))
+
+ ## Check error conditions.
+ _ = st0.extract(200)
+ me.assertRaises(ValueError, st0.extract, 201)
+ st0.mix(T.span(200))
+ me.assertRaises(ValueError, st0.mix, T.span(201))
+
+ def check_shake(me, xcls, c, done_matches_xof = True):
+ """
+ Test the SHAKE and cSHAKE XOFs.
+
+ This is also used for testing KMAC, but that sets DONE_MATCHES_XOF false
+ to indicate that the XOF output is range-separated from the fixed-length
+ outputs (unlike the basic SHAKE functions).
+ """
+
+ ## Check the hash attributes.
+ x = xcls()
+ me.assertEqual(x.rate, 200 - c)
+ me.assertEqual(x.buffered, 0)
+ me.assertEqual(x.state, "absorb")
+
+ ## Set some initial values.
+ func = T.bin("TESTXOF")
+ perso = T.bin("catacomb-python test")
+ m = T.span(167)
+ h0 = xcls().hash(m).done(193)
+ me.assertEqual(len(h0), 193)
+ h1 = xcls(func = func, perso = perso).hash(m).done(193)
+ me.assertEqual(len(h1), 193)
+ me.assertNotEqual(h0, h1)
+
+ ## Check input and output in pieces, and the state machine.
+ if done_matches_xof: h = h0
+ else: h = xcls().hash(m).xof().get(len(h0))
+ x = xcls().hash(m[0:76]).hash(m[76:167]).xof()
+ me.assertEqual(h, x.get(98) + x.get(95))
+
+ ## Check masking.
+ x = xcls().hash(m).xof()
+ me.assertEqual(x.mask(m), C.ByteString(m) ^ C.ByteString(h[0:len(m)]))
+
+ ## Check the `check' method.
+ me.assertTrue(xcls().hash(m).check(h0))
+ me.assertFalse(xcls().hash(m).check(h1))
+
+ ## Check the menagerie of random hashing methods.
+ def mkhash(_):
+ x = xcls(func = func, perso = perso)
+ return x, lambda: x.done(100 - x.rate//2)
+ me.check_hashbuffer(mkhash)
+
+ ## Check the state machine tracking.
+ x = xcls(); me.assertEqual(x.state, "absorb")
+ x.hash(m); me.assertEqual(x.state, "absorb")
+ xx = x.copy()
+ h = xx.done(100 - x.rate//2)
+ me.assertEqual(xx.state, "dead")
+ me.assertRaises(ValueError, xx.done, 1)
+ me.assertRaises(ValueError, xx.get, 1)
+ me.assertEqual(x.state, "absorb")
+ me.assertRaises(ValueError, x.get, 1)
+ x.xof(); me.assertEqual(x.state, "squeeze")
+ me.assertRaises(ValueError, x.done, 1)
+ _ = x.get(1)
+ yy = x.copy(); me.assertEqual(yy.state, "squeeze")
+
+ def test_shake128(me): me.check_shake(C.Shake128, 32)
+ def test_shake256(me): me.check_shake(C.Shake256, 64)
+
+ def check_kmac(me, mcls, c):
+ k = T.span(32)
+ me.check_shake(lambda func = None, perso = T.bin(""):
+ mcls(k, perso = perso),
+ c, done_matches_xof = False)
+
+ def test_kmac128(me): me.check_kmac(C.KMAC128, 32)
+ def test_kmac256(me): me.check_kmac(C.KMAC256, 64)
+
+###--------------------------------------------------------------------------
+class TestPRP (T.GenericTestMixin):
+ """Test pseudorandom permutations (PRPs)."""
+
+ def _test_prp(me, pcls):
+
+ ## Check the PRP properties.
+ me.assertEqual(type(pcls.name), str)
+ me.assertTrue(isinstance(pcls.keysz, C.KeySZ))
+ me.assertEqual(type(pcls.blksz), int)
+
+ ## Check round-tripping.
+ k = T.span(pcls.keysz.default)
+ key = pcls(k)
+ m = T.span(pcls.blksz)
+ c = key.encrypt(m)
+ me.assertEqual(len(c), pcls.blksz)
+ me.assertEqual(m, key.decrypt(c))
+
+ ## Check that bad key lengths are rejected.
+ badlen = bad_key_size(pcls.keysz)
+ if badlen is not None: me.assertRaises(ValueError, pcls, T.span(badlen))
+
+ ## Check that bad blocks are rejected.
+ badblk = T.span(pcls.blksz + 1)
+ me.assertRaises(ValueError, key.encrypt, badblk)
+ me.assertRaises(ValueError, key.decrypt, badblk)
+
+TestPRP.generate_testcases((name, C.gcprps[name]) for name in
+ ["desx", "blowfish", "rijndael"])
+
+###----- That's all, folks --------------------------------------------------
+
+if __name__ == "__main__": U.main()