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# Copyright (c) 2014, Legrandin <helderijs@gmail.com>
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import os
import re
import unittest
from binascii import unhexlify, hexlify

from Cryptodome.Util.py3compat import b, tobytes, bchr
from Cryptodome.Util.strxor import strxor_c
from Cryptodome.Util._file_system import pycryptodome_filename
from Cryptodome.SelfTest.st_common import list_test_cases

from Cryptodome.Hash import BLAKE2b, BLAKE2s


class Blake2Test(unittest.TestCase):

    def test_new_positive(self):

        h = self.BLAKE2.new(digest_bits=self.max_bits)
        for new_func in self.BLAKE2.new, h.new:

            for dbits in xrange(8, self.max_bits + 1, 8):
                hobj = new_func(digest_bits=dbits)
                self.assertEqual(hobj.digest_size, dbits // 8)

            for dbytes in xrange(1, self.max_bytes + 1):
                hobj = new_func(digest_bytes=dbytes)
                self.assertEqual(hobj.digest_size, dbytes)

            digest1 = new_func(data=b("\x90"), digest_bytes=self.max_bytes).digest()
            digest2 = new_func(digest_bytes=self.max_bytes).update(b("\x90")).digest()
            self.assertEqual(digest1, digest2)

            new_func(data=b("A"), key=b("5"), digest_bytes=self.max_bytes)

        hobj = h.new()
        self.assertEqual(hobj.digest_size, self.max_bytes)

    def test_new_negative(self):

        self.assertRaises(TypeError, self.BLAKE2.new)

        h = self.BLAKE2.new(digest_bits=self.max_bits)
        for new_func in self.BLAKE2.new, h.new:
            self.assertRaises(TypeError, new_func,
                              digest_bytes=self.max_bytes,
                              digest_bits=self.max_bits)
            self.assertRaises(ValueError, new_func, digest_bytes=0)
            self.assertRaises(ValueError, new_func,
                              digest_bytes=self.max_bytes + 1)
            self.assertRaises(ValueError, new_func, digest_bits=7)
            self.assertRaises(ValueError, new_func, digest_bits=15)
            self.assertRaises(ValueError, new_func,
                              digest_bits=self.max_bits + 1)
            self.assertRaises(TypeError, new_func,
                              digest_bytes=self.max_bytes,
                              key=u"string")
            self.assertRaises(TypeError, new_func,
                              digest_bytes=self.max_bytes,
                              data=u"string")

    def test_update(self):
        pieces = [bchr(10) * 200, bchr(20) * 300]
        h = self.BLAKE2.new(digest_bytes=self.max_bytes)
        h.update(pieces[0]).update(pieces[1])
        digest = h.digest()
        h = self.BLAKE2.new(digest_bytes=self.max_bytes)
        h.update(pieces[0] + pieces[1])
        self.assertEqual(h.digest(), digest)

    def test_update_negative(self):
        h = self.BLAKE2.new(digest_bytes=self.max_bytes)
        self.assertRaises(TypeError, h.update, u"string")

    def test_digest(self):
        h = self.BLAKE2.new(digest_bytes=self.max_bytes)
        digest = h.digest()

        # hexdigest does not change the state
        self.assertEqual(h.digest(), digest)
        # digest returns a byte string
        self.failUnless(isinstance(digest, type(b("digest"))))

    def test_update_after_digest(self):
        msg=b("rrrrttt")

        #import pdb; pdb.set_trace()

        # Normally, update() cannot be done after digest()
        h = self.BLAKE2.new(digest_bits=256, data=msg[:4])
        dig1 = h.digest()
        self.assertRaises(TypeError, h.update, msg[4:])
        dig2 = self.BLAKE2.new(digest_bits=256, data=msg).digest()

        # With the proper flag, it is allowed
        h = self.BLAKE2.new(digest_bits=256, data=msg[:4], update_after_digest=True)
        self.assertEquals(h.digest(), dig1)
        # ... and the subsequent digest applies to the entire message
        # up to that point
        h.update(msg[4:])
        self.assertEquals(h.digest(), dig2)

    def test_hex_digest(self):
        mac = self.BLAKE2.new(digest_bits=self.max_bits)
        digest = mac.digest()
        hexdigest = mac.hexdigest()

        # hexdigest is equivalent to digest
        self.assertEqual(hexlify(digest), tobytes(hexdigest))
        # hexdigest does not change the state
        self.assertEqual(mac.hexdigest(), hexdigest)
        # hexdigest returns a string
        self.failUnless(isinstance(hexdigest, type("digest")))

    def test_verify(self):
        h = self.BLAKE2.new(digest_bytes=self.max_bytes, key=b("4"))
        mac = h.digest()
        h.verify(mac)
        wrong_mac = strxor_c(mac, 255)
        self.assertRaises(ValueError, h.verify, wrong_mac)

    def test_hexverify(self):
        h = self.BLAKE2.new(digest_bytes=self.max_bytes, key=b("4"))
        mac = h.hexdigest()
        h.hexverify(mac)
        self.assertRaises(ValueError, h.hexverify, "4556")

    def test_oid(self):

        prefix = "1.3.6.1.4.1.1722.12.2." + self.oid_variant + "."

        for digest_bits in self.digest_bits_oid:
            h = self.BLAKE2.new(digest_bits=digest_bits)
            self.assertEqual(h.oid, prefix + str(digest_bits // 8))

            h = self.BLAKE2.new(digest_bits=digest_bits, key=b("secret"))
            self.assertRaises(AttributeError, lambda: h.oid)

        for digest_bits in (8, self.max_bits):
            if digest_bits in self.digest_bits_oid:
                continue
            self.assertRaises(AttributeError, lambda: h.oid)


class Blake2bTest(Blake2Test):
    #: Module
    BLAKE2 = BLAKE2b
    #: Max output size (in bits)
    max_bits = 512
    #: Max output size (in bytes)
    max_bytes = 64
    #: Bit size of the digests for which an ASN OID exists
    digest_bits_oid = (160, 256, 384, 512)
    # http://tools.ietf.org/html/draft-saarinen-blake2-02
    oid_variant = "1"


class Blake2sTest(Blake2Test):
    #: Module
    BLAKE2 = BLAKE2s
    #: Max output size (in bits)
    max_bits = 256
    #: Max output size (in bytes)
    max_bytes = 32
    #: Bit size of the digests for which an ASN OID exists
    digest_bits_oid = (128, 160, 224, 256)
    # http://tools.ietf.org/html/draft-saarinen-blake2-02
    oid_variant = "2"


class Blake2OfficialTestVector(unittest.TestCase):

    def setUp(self):

        test_vector_file = pycryptodome_filename(
                            ("Cryptodome", "SelfTest", "Hash", "test_vectors", self.name),
                            self.name.lower() + "-test.txt")

        expected = "in"
        self.test_vectors = []
        for line_number, line in enumerate(open(test_vector_file, "rt")):

            if line.strip() == "" or line.startswith("#"):
                continue

            res = re.match("%s:\t([0-9A-Fa-f]*)" % expected, line)
            if not res:
                raise ValueError("Incorrect test vector format (line %d)"
                                 % line_number)

            if res.group(1):
                bin_value = unhexlify(tobytes(res.group(1)))
            else:
                bin_value = b("")
            if expected == "in":
                input_data = bin_value
                expected = "key"
            elif expected == "key":
                key = bin_value
                expected = "hash"
            else:
                result = bin_value
                expected = "in"
                self.test_vectors.append((input_data, key, result))

    def runTest(self):
        for (input_data, key, result) in self.test_vectors:
            mac = self.BLAKE2.new(key=key, digest_bytes=self.max_bytes)
            mac.update(input_data)
            self.assertEqual(mac.digest(), result)


class Blake2bOfficialTestVector(Blake2OfficialTestVector):
    #: Module
    BLAKE2 = BLAKE2b
    #: Hash name
    name = "BLAKE2b"
    #: Max digest size
    max_bytes = 64


class Blake2sOfficialTestVector(Blake2OfficialTestVector):
    #: Module
    BLAKE2 = BLAKE2s
    #: Hash name
    name = "BLAKE2s"
    #: Max digest size
    max_bytes = 32


class Blake2TestVector1(unittest.TestCase):

    def setUp(self):
        test_vector_file = pycryptodome_filename(
                            ("Cryptodome", "SelfTest", "Hash", "test_vectors", self.name),
                            "tv1.txt")

        self.test_vectors = []
        for line_number, line in enumerate(open(test_vector_file, "rt")):
            if line.strip() == "" or line.startswith("#"):
                continue
            res = re.match("digest: ([0-9A-Fa-f]*)", line)
            if not res:
                raise ValueError("Incorrect test vector format (line %d)"
                                 % line_number)

            self.test_vectors.append(unhexlify(tobytes(res.group(1))))

    def runTest(self):

        for tv in self.test_vectors:
            digest_bytes = len(tv)
            next_data = b("")
            for _ in xrange(100):
                h = self.BLAKE2.new(digest_bytes=digest_bytes)
                h.update(next_data)
                next_data = h.digest() + next_data
            self.assertEqual(h.digest(), tv)


class Blake2bTestVector1(Blake2TestVector1):
    #: Module
    BLAKE2 = BLAKE2b
    #: Hash name
    name = "BLAKE2b"


class Blake2sTestVector1(Blake2TestVector1):
    #: Module
    BLAKE2 = BLAKE2s
    #: Hash name
    name = "BLAKE2s"


class Blake2TestVector2(unittest.TestCase):

    def setUp(self):
        test_vector_file = pycryptodome_filename(
                            ("Cryptodome", "SelfTest", "Hash", "test_vectors", self.name),
                            "tv2.txt")

        self.test_vectors = []
        for line_number, line in enumerate(open(test_vector_file, "rt")):
            if line.strip() == "" or line.startswith("#"):
                continue
            res = re.match("digest\(([0-9]+)\): ([0-9A-Fa-f]*)", line)
            if not res:
                raise ValueError("Incorrect test vector format (line %d)"
                                 % line_number)

            key_size = int(res.group(1))
            result = unhexlify(tobytes(res.group(2)))
            self.test_vectors.append((key_size, result))

    def runTest(self):

        for key_size, result in self.test_vectors:
            next_data = b("")
            for _ in xrange(100):
                h = self.BLAKE2.new(digest_bytes=self.max_bytes,
                                    key=b("A" * key_size))
                h.update(next_data)
                next_data = h.digest() + next_data
            self.assertEqual(h.digest(), result)


class Blake2bTestVector2(Blake2TestVector1):
    #: Module
    BLAKE2 = BLAKE2b
    #: Hash name
    name = "BLAKE2b"
    #: Max digest size in bytes
    max_bytes = 64


class Blake2sTestVector2(Blake2TestVector1):
    #: Module
    BLAKE2 = BLAKE2s
    #: Hash name
    name = "BLAKE2s"
    #: Max digest size in bytes
    max_bytes = 32


def get_tests(config={}):
    tests = []

    tests += list_test_cases(Blake2bTest)
    tests.append(Blake2bOfficialTestVector())
    tests.append(Blake2bTestVector1())
    tests.append(Blake2bTestVector2())

    tests += list_test_cases(Blake2sTest)
    tests.append(Blake2sOfficialTestVector())
    tests.append(Blake2sTestVector1())
    tests.append(Blake2sTestVector2())

    return tests


if __name__ == '__main__':
    import unittest
    suite = lambda: unittest.TestSuite(get_tests())
    unittest.main(defaultTest='suite')
