#!/usr/bin/env python
# -*- coding: utf8 -*-
import os
import rsa
import json
import hashlib
import base64
from Crypto.Cipher import AES
from ..settings_manager import settings
class RSAEncrypter(object):
  """RSA加密解密
  參考 https://stuvel.eu/python-rsa-doc/index.html
  對應JavaScript版本參考 https://github.com/travist/jsencrypt
  [description]
  """
  @classmethod
  def encrypt(cls, plaintext, keydata):
    #明文編碼格式
    content = plaintext.encode('utf8')
    if os.path.isfile(keydata):
      with open(keydata) as publicfile:
        keydata = publicfile.read()
    pubkey = rsa.PublicKey.load_pkcs1_openssl_pem(keydata)
    #公鑰加密
    crypto = rsa.encrypt(content, pubkey)
    return base64.b64encode(crypto).decode('utf8')
  @classmethod
  def decrypt(cls, ciphertext, keydata):
    if os.path.isfile(keydata):
      with open(keydata) as privatefile:
        keydata = privatefile.read()
    try:
      ciphertext = base64.b64decode(ciphertext)
      privkey = rsa.PrivateKey.load_pkcs1(keydata, format='PEM')
      con = rsa.decrypt(ciphertext, privkey)
      return con.decode('utf8')
    except Exception as e:
      pass
    return False
  @classmethod
  def signing(cls, message, privkey):
    """ 簽名
      https://legrandin.github.io/pycryptodome/Doc/3.2/Crypto.Signature.pkcs1_15-module.html
    """
    from Crypto.Signature import pkcs1_15
    from Crypto.Hash import SHA256
    from Crypto.PublicKey import RSA
    if os.path.isfile(privkey):
      with open(privkey) as privatefile:
        privkey = privatefile.read()
    try:
      key = RSA.import_key(privkey)
      h = SHA256.new(message.encode('utf8'))
      sign = pkcs1_15.new(key).sign(h)
      sign = base64.b64encode(sign).decode('utf8')
      return sign
    except Exception as e:
      raise e
  @classmethod
  def verify(cls, message, sign, pubkey):
    """ 驗證簽名
      https://legrandin.github.io/pycryptodome/Doc/3.2/Crypto.Signature.pkcs1_15-module.html
    """
    from Crypto.Signature import pkcs1_15
    from Crypto.Hash import SHA256
    from Crypto.PublicKey import RSA
    res = False
    sign = base64.b64decode(sign)
    # print('sign', type(sign), sign)
    try:
      key = RSA.importKey(pubkey)
      h = SHA256.new(message.encode('utf8'))
      pkcs1_15.new(key).verify(h, sign)
      res = True
    except (ValueError, TypeError) as e:
      raise e
      pass
    except Exception as e:
      raise e
      pass
    return res
class AESEncrypter(object):
  def __init__(self, key, iv=None):
    self.key = key.encode('utf8')
    self.iv = iv if iv else bytes(key[0:16], 'utf8')
  def _pad(self, text):
    text_length = len(text)
    padding_len = AES.block_size - int(text_length % AES.block_size)
    if padding_len == 0:
      padding_len = AES.block_size
    t2 = chr(padding_len) * padding_len
    t2 = t2.encode('utf8')
    # print('text ', type(text), text)
    # print('t2 ', type(t2), t2)
    t3 = text + t2
    return t3
  def _unpad(self, text):
    pad = ord(text[-1])
    return text[:-pad]
  def encrypt(self, raw):
    raw = raw.encode('utf8')
    raw = self._pad(raw)
    cipher = AES.new(self.key, AES.MODE_CBC, self.iv)
    encrypted = cipher.encrypt(raw)
    return base64.b64encode(encrypted).decode('utf8')
  def decrypt(self, enc):
    enc = enc.encode('utf8')
    enc = base64.b64decode(enc)
    cipher = AES.new(self.key, AES.MODE_CBC, self.iv)
    decrypted = cipher.decrypt(enc)
    return self._unpad(decrypted.decode('utf8'))
class AESSkyPay:
  """
  Tested under Python 3.7 and pycryptodome
  """
  BLOCK_SIZE = 16
  def __init__(self, key):
    #菲律賓支付通道 SkyPay Payment Specification.lending.v1.16.pdf
    # SkyPay 對密碼做了如下處理
    s1 = hashlib.sha1(bytes(key, encoding='utf-8')).digest()
    s2 = hashlib.sha1(s1).digest()
    self.key = s2[0:16]
    self.mode = AES.MODE_ECB
  def pkcs5_pad(self,s):
    """
    padding to blocksize according to PKCS #5
    calculates the number of missing chars to BLOCK_SIZE and pads with
    ord(number of missing chars)
    @see: http://www.di-mgt.com.au/cryptopad.html
    @param s: string to pad
    @type s: string
    @rtype: string
    """
    BS = self.BLOCK_SIZE
    return s + ((BS - len(s) % BS) * chr(BS - len(s) % BS)).encode('utf8')
  def pkcs5_unpad(self,s):
    """
    unpadding according to PKCS #5
    @param s: string to unpad
    @type s: string
    @rtype: string
    """
    return s[:-ord(s[len(s) - 1:])]
  # 加密函數，如果text不足16位就用空格補足為16位，
  # 如果大于16當時不是16的倍數，那就補足為16的倍數。
  # 補足方法：PKCS5
  def encrypt(self, text):
    cryptor = AES.new(self.key, self.mode)
    # 這里密鑰key 長度必須為16（AES-128）,
    # 24（AES-192）,或者32 （AES-256）Bytes 長度
    # 目前AES-128 足夠目前使用
    ciphertext = cryptor.encrypt(self.pkcs5_pad(text.encode('utf8')))
    # 因為AES加密時候得到的字符串不一定是ascii字符集的，輸出到終端或者保存時候可能存在問題
    # 所以這里將加密的字符串進行base64編碼
    return base64.b64encode(ciphertext).decode()
  def decrypt(self, text):
    cryptor = AES.new(self.key, self.mode)
    plain_text = cryptor.decrypt(base64.b64decode(text))
    return bytes.decode(self.pkcs5_unpad(plain_text))
def aes_decrypt(ciphertext, secret=None, prefix='aes:::'):
  secret = secret if secret else settings.default_aes_secret
  cipher = AESEncrypter(secret)
  prefix_len = len(prefix)
  if ciphertext[0:prefix_len]==prefix:
    return cipher.decrypt(ciphertext[prefix_len:])
  else:
    return ciphertext
def aes_encrypt(plaintext, secret=None, prefix='aes:::'):
  secret = secret if secret else settings.default_aes_secret
  cipher = AESEncrypter(secret)
  encrypted = cipher.encrypt(plaintext)
  return '%s%s' % (prefix, encrypted)
if __name__ == "__main__":
  try:
    # for RSA test
    ciphertext = 'Qa2EU2EF4Eq4w75TnA1IUw+ir9l/nSdW3pMV+a6FkzV9bld259DxM1M4RxYkpPaVXhQFol04yFjuxzkRg12e76i6pkDM1itQSOy5hwmrud5PQvfnBf7OmHpOpS6oh7OQo72CA0LEzas+OANmRXKfn5CMN14GsmfWAn/F6j4Azhs='
    public_key = '/Users/leeyi/workspace/joywin_staff/joywin_staff_api/datas/public.pem'
    private_key = '/Users/leeyi/workspace/joywin_staff/joywin_staff_api/datas/private.pem'
    ciphertext = RSAEncrypter.encrypt('admin888中國', public_key)
    print("ciphertext: ", ciphertext)
    plaintext = RSAEncrypter.decrypt(ciphertext, private_key)
    print("plaintext: ", type(plaintext))
    print("plaintext: ", plaintext)
    # for AES test
    key = 'abc20304050607081q2w3e4r*1K|j!ta'
    cipher = AESEncrypter(key)
    plaintext = '542#1504'
    encrypted = cipher.encrypt(plaintext)
    print('Encrypted: %s' % encrypted)
    ciphertext = 'EPLtushldq9E1U8vG/sL3g=='
    assert encrypted == ciphertext
    plaintext = '542#1504你好'
    encrypted = '+YGDvnakKi77SBD6GXmThw=='
    decrypted = cipher.decrypt(encrypted)
    print('Decrypted: %s' % decrypted)
    assert decrypted == plaintext
  except KeyboardInterrupt:
    sys.exit(0)

#!/usr/bin/env python3
# coding=utf-8
# Author: Luosu201803
"""
create_rsa_key() - 創建RSA密鑰
my_encrypt_and_decrypt() - 測試加密解密功能
rsa_sign() & rsa_signverify() - 測試簽名與驗簽功能
"""
from binascii import unhexlify
from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_OAEP, PKCS1_v1_5
import base64
from Crypto.Hash import SHA1
from Crypto.Signature import pkcs1_15
def create_rsa_key(password="123456"):
  """
  創建RSA密鑰,步驟說明：
  1、從 Crypto.PublicKey 包中導入 RSA，創建一個密碼(此密碼不是RSA秘鑰對)
  2、生成 1024/2048 位的 RSA 密鑰對(存儲在私鑰文件和公鑰文件)
  3、調用 RSA 密鑰實例的 exportKey 方法(傳入"密碼"、"使用的 PKCS 標準"、"加密方案"這三個參數)得到私鑰。
  4、將私鑰寫入磁盤的文件。
  5、使用方法鏈調用 publickey 和 exportKey 方法生成公鑰，寫入磁盤上的文件。
  """
  key = RSA.generate(1024)
  encrypted_key = key.exportKey(passphrase=password, pkcs=8,protection="scryptAndAES128-CBC")
  # encrypted_key = key.exportKey(pkcs=1)
  print('encrypted_key:',encrypted_key)
  with open("my_private_rsa_key.pem", "wb") as f:
    f.write(encrypted_key)
  with open("my_rsa_public.pem", "wb") as f:
    f.write(key.publickey().exportKey())
def encrypt_and_decrypt_test(password="123456"):
  # 加載私鑰用于加密
  recipient_key = RSA.import_key(
    open("my_rsa_public.pem").read()
  )
  cipher_rsa = PKCS1_v1_5.new(recipient_key)
  #使用base64編碼保存數據方便查看，同樣解密需要base64解碼
  en_data = base64.b64encode(cipher_rsa.encrypt(b"123456,abcdesd"))
  print("加密數據信息：",type(en_data),'\n',len(en_data),'\n',en_data)
  # 加載公鑰用于解密
  encoded_key = open("my_private_rsa_key.pem").read()
  private_key = RSA.import_key(encoded_key,passphrase=password)
  cipher_rsa = PKCS1_v1_5.new(private_key)
  data = cipher_rsa.decrypt(base64.b64decode(en_data), None)
  print(data)
def rsa_sign(message,password="123456"):
  #讀取私鑰信息用于加簽
  private_key = RSA.importKey(open("my_private_rsa_key.pem").read(),passphrase=password)
  hash_obj = SHA1.new(message)
  # print(pkcs1_15.new(private_key).can_sign()) #check wheather object of pkcs1_15 can be signed
  #base64編碼打印可視化
  signature = base64.b64encode(pkcs1_15.new(private_key).sign(hash_obj))
  return signature
def rsa_signverify(message,signature):
  #讀取公鑰信息用于驗簽
  public_key = RSA.importKey(open("my_rsa_public.pem").read())
  #message做“哈希”處理，RSA簽名這么要求的
  hash_obj = SHA1.new(message)
  try:
    #因為簽名被base64編碼，所以這里先解碼，再驗簽
    pkcs1_15.new(public_key).verify(hash_obj,base64.b64decode(signature))
    print('The signature is valid.')
    return True
  except (ValueError,TypeError):
    print('The signature is invalid.')
if __name__ == '__main__':
  # create_rsa_key()
  encrypt_and_decrypt_test()
  # message = b'Luosu is a Middle-aged uncle.'
  # signature = rsa_sign(message)
  # print('signature:',signature)
  # print(rsa_signverify(message,signature))