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from __future__ import unicode_literals
from __future__ import absolute_import
import shutil
import tempfile
import textwrap
import os

from paste.deploy.converters import asint
import ming
from cryptography.hazmat.primitives.twofactor import InvalidToken
from mock import patch, Mock
from nose.tools import assert_equal, assert_raises
from tg import config

from allura import model as M
from allura.lib.exceptions import InvalidRecoveryCode, MultifactorRateLimitError
from allura.lib.multifactor import GoogleAuthenticatorFile, TotpService, MongodbTotpService
from allura.lib.multifactor import GoogleAuthenticatorPamFilesystemTotpService
from allura.lib.multifactor import RecoveryCodeService, MongodbRecoveryCodeService
from allura.lib.multifactor import GoogleAuthenticatorPamFilesystemRecoveryCodeService


class TestGoogleAuthenticatorFile(object):
    sample = textwrap.dedent('''\
        7CL3WL756ISQCU5HRVNAODC44Q
        " RATE_LIMIT 3 30
        " DISALLOW_REUSE
        " TOTP_AUTH
        43504045
        16951331
        16933944
        38009587
        49571579
        ''')
    # different key length
    sample2 = textwrap.dedent('''\
        LQQTTQUEW3VAGA6O5XICCWGBXUWXI737
        " TOTP_AUTH
        ''')

    def test_parse(self):
        gaf = GoogleAuthenticatorFile.load(self.sample)
        assert_equal(gaf.key, b'\xf8\x97\xbb/\xfd\xf2%\x01S\xa7\x8dZ\x07\x0c\\\xe4')
        assert_equal(gaf.options['RATE_LIMIT'], '3 30')
        assert_equal(gaf.options['DISALLOW_REUSE'], None)
        assert_equal(gaf.options['TOTP_AUTH'], None)
        assert_equal(gaf.recovery_codes, [
            '43504045',
            '16951331',
            '16933944',
            '38009587',
            '49571579',
        ])

    def test_dump(self):
        gaf = GoogleAuthenticatorFile.load(self.sample)
        assert_equal(gaf.dump(), self.sample)

    def test_dump2(self):
        gaf = GoogleAuthenticatorFile.load(self.sample2)
        assert_equal(gaf.dump(), self.sample2)


class GenericTotpService(TotpService):
    def enforce_rate_limit(self, *args, **kwargs):
        pass


class TestTotpService(object):

    sample_key = b'\x00K\xda\xbfv\xc2B\xaa\x1a\xbe\xa5\x96b\xb2\xa0Z:\xc9\xcf\x8a'
    sample_time = 1472502664
    # these generate code 283397

    def test_constructor(self):
        totp = TotpService().Totp(key=None)
        assert totp

    @patch('allura.lib.multifactor.time')
    def test_verify_types(self, time):
        time.return_value = self.sample_time
        srv = GenericTotpService()
        totp = srv.Totp(key=self.sample_key)
        srv.verify(totp, '283 397', None)
        srv.verify(totp, '283397', None)

    @patch('allura.lib.multifactor.time')
    def test_verify_window(self, time):
        time.return_value = self.sample_time
        srv = GenericTotpService()
        totp = srv.Totp(key=self.sample_key)
        srv.verify(totp, '283397', None)

        time.return_value = self.sample_time + 30
        srv.verify(totp, '283397', None)

        time.return_value = self.sample_time + 60
        with assert_raises(InvalidToken):
            srv.verify(totp, '283397', None)

        time.return_value = self.sample_time - 30
        with assert_raises(InvalidToken):
            srv.verify(totp, '283397', None)

    def test_get_qr_code(self):
        srv = TotpService()
        totp = srv.Totp(key=None)
        user = Mock(username='some-user-guy')
        config['site_name'] = 'Our Website'
        assert srv.get_qr_code(totp, user)


class TestAnyTotpServiceImplementation(object):

    __test__ = False

    sample_key = b'\x00K\xda\xbfv\xc2B\xaa\x1a\xbe\xa5\x96b\xb2\xa0Z:\xc9\xcf\x8a'
    sample_time = 1472502664
    # these generate code 283397

    def mock_user(self):
        return M.User(username='some-user-guy')

    def test_none(self):
        srv = self.Service()
        user = self.mock_user()
        assert_equal(None, srv.get_secret_key(user))

    def test_set_get(self):
        srv = self.Service()
        user = self.mock_user()
        srv.set_secret_key(user, self.sample_key)
        assert_equal(self.sample_key, srv.get_secret_key(user))

    def test_delete(self):
        srv = self.Service()
        user = self.mock_user()
        srv.set_secret_key(user, self.sample_key)
        assert_equal(self.sample_key, srv.get_secret_key(user))
        srv.set_secret_key(user, None)
        assert_equal(None, srv.get_secret_key(user))

    @patch('allura.lib.multifactor.time')
    def test_rate_limiting(self, time):
        time.return_value = self.sample_time
        srv = self.Service()
        user = self.mock_user()
        totp = srv.Totp(key=self.sample_key)

        # 4th attempt (good or bad) will trip over the default limit of 3 in 30s
        with assert_raises(InvalidToken):
            srv.verify(totp, '34dfvdasf', user)
        with assert_raises(InvalidToken):
            srv.verify(totp, '234asdfsadf', user)
        srv.verify(totp, '283397', user)
        with assert_raises(MultifactorRateLimitError):
            srv.verify(totp, '283397', user)


class TestMongodbTotpService(TestAnyTotpServiceImplementation):

    __test__ = True
    Service = MongodbTotpService

    def setUp(self):
        config = {
            'ming.main.uri': 'mim://allura_test',
        }
        ming.configure(**config)


class TestGoogleAuthenticatorPamFilesystemMixin(object):

    def setUp(self):
        self.totp_basedir = tempfile.mkdtemp(prefix='totp-test', dir=os.getenv('TMPDIR', '/tmp'))
        config['auth.multifactor.totp.filesystem.basedir'] = self.totp_basedir

    def tearDown(self):
        if os.path.exists(self.totp_basedir):
            shutil.rmtree(self.totp_basedir)


class TestGoogleAuthenticatorPamFilesystemTotpService(TestAnyTotpServiceImplementation,
                                                      TestGoogleAuthenticatorPamFilesystemMixin):

    __test__ = True
    Service = GoogleAuthenticatorPamFilesystemTotpService

    def test_rate_limiting(self):
        # make a regular .google-authenticator file first, so rate limit info has somewhere to go
        self.Service().set_secret_key(self.mock_user(), self.sample_key)
        # then run test
        super(TestGoogleAuthenticatorPamFilesystemTotpService, self).test_rate_limiting()


class TestRecoveryCodeService(object):

    def test_generate_one_code(self):
        code = RecoveryCodeService().generate_one_code()
        assert code
        another_code = RecoveryCodeService().generate_one_code()
        assert code != another_code

    def test_regenerate_codes(self):
        class DummyRecoveryService(RecoveryCodeService):
            def replace_codes(self, user, codes):
                self.saved_user = user
                self.saved_codes = codes
        recovery = DummyRecoveryService()
        user = Mock(username='some-user-guy')

        recovery.regenerate_codes(user)

        assert_equal(recovery.saved_user, user)
        assert_equal(len(recovery.saved_codes), asint(config.get('auth.multifactor.recovery_code.count', 10)))


class TestAnyRecoveryCodeServiceImplementation(object):

    __test__ = False

    def mock_user(self):
        return M.User(username='some-user-guy')

    def test_get_codes_none(self):
        recovery = self.Service()
        user = self.mock_user()
        assert_equal(recovery.get_codes(user), [])

    def test_regen_get_codes(self):
        recovery = self.Service()
        user = self.mock_user()
        recovery.regenerate_codes(user)
        assert recovery.get_codes(user)

    def test_replace_codes(self):
        recovery = self.Service()
        user = self.mock_user()
        codes = [
            '12345',
            '67890'
        ]
        recovery.replace_codes(user, codes)
        assert_equal(recovery.get_codes(user), codes)

    def test_verify_fail(self):
        recovery = self.Service()
        user = self.mock_user()
        with assert_raises(InvalidRecoveryCode):
            recovery.verify_and_remove_code(user, '11111')
        with assert_raises(InvalidRecoveryCode):
            recovery.verify_and_remove_code(user, '')

    def test_verify_and_remove_code(self):
        recovery = self.Service()
        user = self.mock_user()
        codes = [
            '12345',
            '67890'
        ]
        recovery.replace_codes(user, codes)
        result = recovery.verify_and_remove_code(user, '12345')
        assert_equal(result, True)
        assert_equal(recovery.get_codes(user), ['67890'])

    def test_rate_limiting(self):
        recovery = self.Service()
        user = self.mock_user()
        codes = [
            '11111',
            '22222',
        ]
        recovery.replace_codes(user, codes)

        # 4th attempt (good or bad) will trip over the default limit of 3 in 30s
        with assert_raises(InvalidRecoveryCode):
            recovery.verify_and_remove_code(user, '13485u0233')
        with assert_raises(InvalidRecoveryCode):
            recovery.verify_and_remove_code(user, '34123rdxafs')
        recovery.verify_and_remove_code(user, '11111')
        with assert_raises(MultifactorRateLimitError):
            recovery.verify_and_remove_code(user, '22222')


class TestMongodbRecoveryCodeService(TestAnyRecoveryCodeServiceImplementation):

    __test__ = True

    Service = MongodbRecoveryCodeService

    def setUp(self):
        config = {
            'ming.main.uri': 'mim://allura_test',
        }
        ming.configure(**config)


class TestGoogleAuthenticatorPamFilesystemRecoveryCodeService(TestAnyRecoveryCodeServiceImplementation,
                                                              TestGoogleAuthenticatorPamFilesystemMixin):

    __test__ = True

    Service = GoogleAuthenticatorPamFilesystemRecoveryCodeService

    def setUp(self):
        super(TestGoogleAuthenticatorPamFilesystemRecoveryCodeService, self).setUp()

        # make a regular .google-authenticator file first, so recovery keys have somewhere to go
        GoogleAuthenticatorPamFilesystemTotpService().set_secret_key(self.mock_user(),
                                                                     b'\x00K\xda\xbfv\xc2B\xaa\x1a\xbe\xa5\x96b\xb2\xa0Z:\xc9\xcf\x8a')

    def test_get_codes_none_when_no_file(self):
        # this deletes the file
        GoogleAuthenticatorPamFilesystemTotpService().set_secret_key(self.mock_user(), None)

        super(TestGoogleAuthenticatorPamFilesystemRecoveryCodeService, self).test_get_codes_none()

    def test_replace_codes_when_no_file(self):
        # this deletes the file
        GoogleAuthenticatorPamFilesystemTotpService().set_secret_key(self.mock_user(), None)

        # then it errors because no .google-authenticator file
        with assert_raises(IOError):
            super(TestGoogleAuthenticatorPamFilesystemRecoveryCodeService, self).test_replace_codes()