# -*- coding: utf-8 -*-
# (c) 2012-2014, Michael DeHaan <michael.dehaan@gmail.com>
# (c) 2016, Toshio Kuratomi <tkuratomi@ansible.com>
#
# This file is part of Ansible
#
# Ansible 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 3 of the License, or
# (at your option) any later version.
#
# Ansible 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 Ansible.  If not, see <http://www.gnu.org/licenses/>.

# Make coding more python3-ish
from __future__ import (absolute_import, division, print_function)
__metaclass__ = type

import binascii
import io
import os

from binascii import hexlify
from nose.plugins.skip import SkipTest

from ansible.compat.tests import unittest

from ansible import errors
from ansible.module_utils import six
from ansible.module_utils._text import to_bytes, to_text
from ansible.parsing.vault import VaultLib
from ansible.parsing import vault


# Counter import fails for 2.0.1, requires >= 2.6.1 from pip
try:
    from Crypto.Util import Counter
    HAS_COUNTER = True
except ImportError:
    HAS_COUNTER = False

# KDF import fails for 2.0.1, requires >= 2.6.1 from pip
try:
    from Crypto.Protocol.KDF import PBKDF2
    HAS_PBKDF2 = True
except ImportError:
    HAS_PBKDF2 = False

# AES IMPORTS
try:
    from Crypto.Cipher import AES as AES
    HAS_AES = True
except ImportError:
    HAS_AES = False


class TestVaultIsEncrypted(unittest.TestCase):
    def test_bytes_not_encrypted(self):
        b_data = b"foobar"
        self.assertFalse(vault.is_encrypted(b_data))

    def test_bytes_encrypted(self):
        b_data = b"$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify(b"ansible")
        self.assertTrue(vault.is_encrypted(b_data))

    def test_text_not_encrypted(self):
        b_data = to_text(b"foobar")
        self.assertFalse(vault.is_encrypted(b_data))

    def test_text_encrypted(self):
        b_data = to_text(b"$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify(b"ansible"))
        self.assertTrue(vault.is_encrypted(b_data))

    def test_invalid_text_not_ascii(self):
        data = u"$ANSIBLE_VAULT;9.9;TEST\n%s" % u"ァ ア ィ イ ゥ ウ ェ エ ォ オ カ ガ キ ギ ク グ ケ "
        self.assertFalse(vault.is_encrypted(data))

    def test_invalid_bytes_not_ascii(self):
        data = u"$ANSIBLE_VAULT;9.9;TEST\n%s" % u"ァ ア ィ イ ゥ ウ ェ エ ォ オ カ ガ キ ギ ク グ ケ "
        b_data = to_bytes(data, encoding='utf-8')
        self.assertFalse(vault.is_encrypted(b_data))


class TestVaultIsEncryptedFile(unittest.TestCase):
    def test_binary_file_handle_not_encrypted(self):
        b_data = b"foobar"
        b_data_fo = io.BytesIO(b_data)
        self.assertFalse(vault.is_encrypted_file(b_data_fo))

    def test_text_file_handle_not_encrypted(self):
        data = u"foobar"
        data_fo = io.StringIO(data)
        self.assertFalse(vault.is_encrypted_file(data_fo))

    def test_binary_file_handle_encrypted(self):
        b_data = b"$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify(b"ansible")
        b_data_fo = io.BytesIO(b_data)
        self.assertTrue(vault.is_encrypted_file(b_data_fo))

    def test_text_file_handle_encrypted(self):
        data = u"$ANSIBLE_VAULT;9.9;TEST\n%s" % to_text(hexlify(b"ansible"))
        data_fo = io.StringIO(data)
        self.assertTrue(vault.is_encrypted_file(data_fo))

    def test_binary_file_handle_invalid(self):
        data = u"$ANSIBLE_VAULT;9.9;TEST\n%s" % u"ァ ア ィ イ ゥ ウ ェ エ ォ オ カ ガ キ ギ ク グ ケ "
        b_data = to_bytes(data)
        b_data_fo = io.BytesIO(b_data)
        self.assertFalse(vault.is_encrypted_file(b_data_fo))

    def test_text_file_handle_invalid(self):
        data = u"$ANSIBLE_VAULT;9.9;TEST\n%s" % u"ァ ア ィ イ ゥ ウ ェ エ ォ オ カ ガ キ ギ ク グ ケ "
        data_fo = io.StringIO(data)
        self.assertFalse(vault.is_encrypted_file(data_fo))

    def test_file_already_read_from_finds_header(self):
        b_data = b"$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify(b"ansible\ntesting\nfile pos")
        b_data_fo = io.BytesIO(b_data)
        b_data_fo.read(42)  # Arbitrary number
        self.assertTrue(vault.is_encrypted_file(b_data_fo))

    def test_file_already_read_from_saves_file_pos(self):
        b_data = b"$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify(b"ansible\ntesting\nfile pos")
        b_data_fo = io.BytesIO(b_data)
        b_data_fo.read(69)  # Arbitrary number
        vault.is_encrypted_file(b_data_fo)
        self.assertEqual(b_data_fo.tell(), 69)

    def test_file_with_offset(self):
        b_data = b"JUNK$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify(b"ansible\ntesting\nfile pos")
        b_data_fo = io.BytesIO(b_data)
        self.assertTrue(vault.is_encrypted_file(b_data_fo, start_pos=4))

    def test_file_with_count(self):
        b_data = b"$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify(b"ansible\ntesting\nfile pos")
        vault_length = len(b_data)
        b_data = b_data + u'ァ ア'.encode('utf-8')
        b_data_fo = io.BytesIO(b_data)
        self.assertTrue(vault.is_encrypted_file(b_data_fo, count=vault_length))

    def test_file_with_offset_and_count(self):
        b_data = b"$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify(b"ansible\ntesting\nfile pos")
        vault_length = len(b_data)
        b_data = b'JUNK' + b_data + u'ァ ア'.encode('utf-8')
        b_data_fo = io.BytesIO(b_data)
        self.assertTrue(vault.is_encrypted_file(b_data_fo, start_pos=4, count=vault_length))


class TestVaultCipherAes256(unittest.TestCase):
    def setUp(self):
        self.vault_cipher = vault.VaultAES256()

    def test(self):
        self.assertIsInstance(self.vault_cipher, vault.VaultAES256)

    # TODO: tag these as slow tests
    def test_create_key(self):
        b_password = b'hunter42'
        b_salt = os.urandom(32)
        b_key = self.vault_cipher._create_key(b_password, b_salt, keylength=32, ivlength=16)
        self.assertIsInstance(b_key, six.binary_type)

    def test_create_key_known(self):
        b_password = b'hunter42'

        # A fixed salt
        b_salt = b'q' * 32  # q is the most random letter.
        b_key = self.vault_cipher._create_key(b_password, b_salt, keylength=32, ivlength=16)
        self.assertIsInstance(b_key, six.binary_type)

        # verify we get the same answer
        # we could potentially run a few iterations of this and time it to see if it's roughly constant time
        #  and or that it exceeds some minimal time, but that would likely cause unreliable fails, esp in CI
        b_key_2 = self.vault_cipher._create_key(b_password, b_salt, keylength=32, ivlength=16)
        self.assertIsInstance(b_key, six.binary_type)
        self.assertEqual(b_key, b_key_2)

    def test_is_equal_is_equal(self):
        self.assertTrue(self.vault_cipher._is_equal(b'abcdefghijklmnopqrstuvwxyz', b'abcdefghijklmnopqrstuvwxyz'))

    def test_is_equal_unequal_length(self):
        self.assertFalse(self.vault_cipher._is_equal(b'abcdefghijklmnopqrstuvwxyz', b'abcdefghijklmnopqrstuvwx and sometimes y'))

    def test_is_equal_not_equal(self):
        self.assertFalse(self.vault_cipher._is_equal(b'abcdefghijklmnopqrstuvwxyz', b'AbcdefghijKlmnopQrstuvwxZ'))

    def test_is_equal_empty(self):
        self.assertTrue(self.vault_cipher._is_equal(b'', b''))

    def test_is_equal_non_ascii_equal(self):
        utf8_data = to_bytes(u'私はガラスを食べられます。それは私を傷つけません。')
        self.assertTrue(self.vault_cipher._is_equal(utf8_data, utf8_data))

    def test_is_equal_non_ascii_unequal(self):
        utf8_data = to_bytes(u'私はガラスを食べられます。それは私を傷つけません。')
        utf8_data2 = to_bytes(u'Pot să mănânc sticlă și ea nu mă rănește.')

        # Test for the len optimization path
        self.assertFalse(self.vault_cipher._is_equal(utf8_data, utf8_data2))
        # Test for the slower, char by char comparison path
        self.assertFalse(self.vault_cipher._is_equal(utf8_data, utf8_data[:-1] + b'P'))

    def test_is_equal_non_bytes(self):
        """ Anything not a byte string should raise a TypeError """
        self.assertRaises(TypeError, self.vault_cipher._is_equal, u"One fish", b"two fish")
        self.assertRaises(TypeError, self.vault_cipher._is_equal, b"One fish", u"two fish")
        self.assertRaises(TypeError, self.vault_cipher._is_equal, 1, b"red fish")
        self.assertRaises(TypeError, self.vault_cipher._is_equal, b"blue fish", 2)


class TestVaultLib(unittest.TestCase):
    def setUp(self):
        self.v = VaultLib('test-vault-password')

    def test_encrypt(self):
        plaintext = u'Some text to encrypt in a café'
        b_vaulttext = self.v.encrypt(plaintext)

        self.assertIsInstance(b_vaulttext, six.binary_type)

        b_header = b'$ANSIBLE_VAULT;1.1;AES256\n'
        self.assertEqual(b_vaulttext[:len(b_header)], b_header)

    def test_encrypt_bytes(self):

        plaintext = to_bytes(u'Some text to encrypt in a café')
        b_vaulttext = self.v.encrypt(plaintext)

        self.assertIsInstance(b_vaulttext, six.binary_type)

        b_header = b'$ANSIBLE_VAULT;1.1;AES256\n'
        self.assertEqual(b_vaulttext[:len(b_header)], b_header)

    def test_is_encrypted(self):
        self.assertFalse(self.v.is_encrypted(b"foobar"), msg="encryption check on plaintext yielded false positive")
        b_data = b"$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify(b"ansible")
        self.assertTrue(self.v.is_encrypted(b_data), msg="encryption check on headered text failed")

    def test_format_output(self):
        self.v.cipher_name = "TEST"
        b_ciphertext = b"ansible"
        b_vaulttext = self.v._format_output(b_ciphertext)
        b_lines = b_vaulttext.split(b'\n')
        self.assertGreater(len(b_lines), 1, msg="failed to properly add header")

        b_header = b_lines[0]
        self.assertTrue(b_header.endswith(b';TEST'), msg="header does not end with cipher name")

        b_header_parts = b_header.split(b';')
        self.assertEqual(len(b_header_parts), 3, msg="header has the wrong number of parts")
        self.assertEqual(b_header_parts[0], b'$ANSIBLE_VAULT', msg="header does not start with $ANSIBLE_VAULT")
        self.assertEqual(b_header_parts[1], self.v.b_version, msg="header version is incorrect")
        self.assertEqual(b_header_parts[2], b'TEST', msg="header does not end with cipher name")

    def test_split_header(self):
        b_vaulttext = b"$ANSIBLE_VAULT;9.9;TEST\nansible"
        b_ciphertext = self.v._split_header(b_vaulttext)
        b_lines = b_ciphertext.split(b'\n')
        self.assertEqual(b_lines[0], b"ansible", msg="Payload was not properly split from the header")
        self.assertEqual(self.v.cipher_name, u'TEST', msg="cipher name was not properly set")
        self.assertEqual(self.v.b_version, b"9.9", msg="version was not properly set")

    def test_encrypt_decrypt_aes(self):
        if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
            raise SkipTest
        self.v.cipher_name = u'AES'
        self.v.b_password = b'ansible'
        # AES encryption code has been removed, so this is old output for
        # AES-encrypted 'foobar' with password 'ansible'.
        b_vaulttext = b'''$ANSIBLE_VAULT;1.1;AES
53616c7465645f5fc107ce1ef4d7b455e038a13b053225776458052f8f8f332d554809d3f150bfa3
fe3db930508b65e0ff5947e4386b79af8ab094017629590ef6ba486814cf70f8e4ab0ed0c7d2587e
786a5a15efeb787e1958cbdd480d076c
'''
        b_plaintext = self.v.decrypt(b_vaulttext)
        self.assertEqual(b_plaintext, b"foobar", msg="decryption failed")

    def test_encrypt_decrypt_aes256(self):
        if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
            raise SkipTest
        self.v.cipher_name = u'AES256'
        plaintext = u"foobar"
        b_vaulttext = self.v.encrypt(plaintext)
        b_plaintext = self.v.decrypt(b_vaulttext)
        self.assertNotEqual(b_vaulttext, b"foobar", msg="encryption failed")
        self.assertEqual(b_plaintext, b"foobar", msg="decryption failed")

    def test_encrypt_decrypt_aes256_existing_vault(self):
        if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
            raise SkipTest
        self.v.cipher_name = u'AES256'
        b_orig_plaintext = b"Setec Astronomy"
        vaulttext = u'''$ANSIBLE_VAULT;1.1;AES256
33363965326261303234626463623963633531343539616138316433353830356566396130353436
3562643163366231316662386565383735653432386435610a306664636137376132643732393835
63383038383730306639353234326630666539346233376330303938323639306661313032396437
6233623062366136310a633866373936313238333730653739323461656662303864663666653563
3138'''

        b_plaintext = self.v.decrypt(vaulttext)
        self.assertEqual(b_plaintext, b_plaintext, msg="decryption failed")

        b_vaulttext = to_bytes(vaulttext, encoding='ascii', errors='strict')
        b_plaintext = self.v.decrypt(b_vaulttext)
        self.assertEqual(b_plaintext, b_orig_plaintext, msg="decryption failed")

    def test_encrypt_decrypt_aes256_bad_hmac(self):
        # FIXME This test isn't working quite yet.
        raise SkipTest

        if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
            raise SkipTest
        self.v.cipher_name = 'AES256'
        # plaintext = "Setec Astronomy"
        enc_data = '''$ANSIBLE_VAULT;1.1;AES256
33363965326261303234626463623963633531343539616138316433353830356566396130353436
3562643163366231316662386565383735653432386435610a306664636137376132643732393835
63383038383730306639353234326630666539346233376330303938323639306661313032396437
6233623062366136310a633866373936313238333730653739323461656662303864663666653563
3138'''
        b_data = to_bytes(enc_data, errors='strict', encoding='utf-8')
        b_data = self.v._split_header(b_data)
        foo = binascii.unhexlify(b_data)
        lines = foo.splitlines()
        # line 0 is salt, line 1 is hmac, line 2+ is ciphertext
        b_salt = lines[0]
        b_hmac = lines[1]
        b_ciphertext_data = b'\n'.join(lines[2:])

        b_ciphertext = binascii.unhexlify(b_ciphertext_data)
        # b_orig_ciphertext = b_ciphertext[:]

        # now muck with the text
        # b_munged_ciphertext = b_ciphertext[:10] + b'\x00' + b_ciphertext[11:]
        # b_munged_ciphertext = b_ciphertext
        # assert b_orig_ciphertext != b_munged_ciphertext

        b_ciphertext_data = binascii.hexlify(b_ciphertext)
        b_payload = b'\n'.join([b_salt, b_hmac, b_ciphertext_data])
        # reformat
        b_invalid_ciphertext = self.v._format_output(b_payload)

        # assert we throw an error
        self.v.decrypt(b_invalid_ciphertext)

    def test_encrypt_encrypted(self):
        if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
            raise SkipTest
        self.v.cipher_name = u'AES'
        b_vaulttext = b"$ANSIBLE_VAULT;9.9;TEST\n%s" % hexlify(b"ansible")
        vaulttext = to_text(b_vaulttext, errors='strict')
        self.assertRaises(errors.AnsibleError, self.v.encrypt, b_vaulttext)
        self.assertRaises(errors.AnsibleError, self.v.encrypt, vaulttext)

    def test_decrypt_decrypted(self):
        if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
            raise SkipTest
        plaintext = u"ansible"
        self.assertRaises(errors.AnsibleError, self.v.decrypt, plaintext)

        b_plaintext = b"ansible"
        self.assertRaises(errors.AnsibleError, self.v.decrypt, b_plaintext)

    def test_cipher_not_set(self):
        # not setting the cipher should default to AES256
        if not HAS_AES or not HAS_COUNTER or not HAS_PBKDF2:
            raise SkipTest
        plaintext = u"ansible"
        self.v.encrypt(plaintext)
        self.assertEquals(self.v.cipher_name, "AES256")