Python 加密 - 代码实现.ipynb

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    "# 加密算法Python实现\n",
    "\n",
    "\n",
    "本文以python实现了一下几种加密算法(主要是python加密库的使用)：\n",
    "　　Base64、MD5，SHA-1，HMAC，DES/AES，RSA\n",
    "\n",
    "\n",
    "## 1、Base64加密\n",
    "### 1.1、算法介绍\n",
    "\n",
    "### 1.2、算法特点\n",
    "　　最简单的加密方式，无密钥，只要拿到密文，就可以直接解密，一般情况下不单独使用，可以和其他加密方式混合使用，作为一层外部包装。\n",
    "\n",
    "### 1.3、代码实现\n",
    "\n",
    "```python\n",
    "import base64\n",
    "\n",
    "# 要加密的字符串\n",
    "str_encrypt = '123456'\n",
    "\n",
    "# 加密方法\n",
    "# 转化为byte类型\n",
    "base64_encrypt = base64.b64encode(str_encrypt.encode())\n",
    "# 将字节串转为字符串\n",
    "base64_encrypt_str = base64_encrypt.decode()\n",
    "print(\"BASE64加密串:\", base64_encrypt_str, type(base64_encrypt_str))\n",
    "\n",
    "#解密方法\n",
    "# 字符串转为字节串\n",
    "base64_decrypt = base64_encrypt_str.encode()\n",
    "# 得到加密的字符串\n",
    "str_decrypt = base64.b64decode(base64_decrypt).decode()\n",
    "print(\"BASE64解密串:\", str_decrypt, type(str_decrypt))\n",
    "```\n",
    "\n",
    "　　BASE64加密串: MTIzNDU2 <class 'str'>   \n",
    "　　BASE64解密串: 123456 <class 'str'>  \n",
    "\n",
    "\n",
    "\n",
    "## 2、MD5加密\n",
    "### 2.1、算法介绍\n",
    "　　MD5 信息-摘要算法（MD5 Message-Digest Algorithm），具有很高的安全性，可以产生出一个128位（16字节）的散列值（hash value），它对应任何字符串都可以加密成一段唯一的固定长度的代码，用于确保信息传输完整一致。目前MD5加密算法是不可逆的，当然这种方式加密的密文也不需要解密，需要的时候直接发送原始密文就好。　　\n",
    "### 2.2、算法特点\n",
    "\n",
    "\n",
    "### 2.3、代码实现\n",
    "\n",
    "```python\n",
    "import hashlib\n",
    "\n",
    "str_encrypt = \"123456\"\n",
    "\n",
    "# 对要加密的字符串进行加密\n",
    "md = hashlib.md5(str_encrypt.encode())\n",
    "md.update(str_encrypt.encode(\"utf8\"))\n",
    "value = md.digest()\n",
    "# 二进制\n",
    "print(\"二进制的字符串\", repr(value))\n",
    "\n",
    "# 十六进制\n",
    "print(\"十六进制的字符串\", md.hexdigest())\n",
    "```\n",
    "　　二进制的字符串：b'\\xe1\\n\\xdc9I\\xbaY\\xab\\xbeV\\xe0W\\xf2\\x0f\\x88>'  \n",
    "　　十六进制的字符串：e10adc3949ba59abbe56e057f20f883e  \n",
    "\n",
    "\n",
    "\n",
    "### 3、SHA1加密\n",
    "### 3.1、算法介绍\n",
    "　　安全哈希算法（Secure Hash Algorithm）主要适用于数字签名标准（Digital Signature Standard DSS）里面定义的数字签名算法（Digital Signature Algorithm DSA），SHA1基于MD5，SHA1比MD5的安全性更强。对于长度小于2^64位的消息，SHA1会产生一个160位的报文摘要。   \n",
    "　　通过散列算法可实现数字签名实现，数字签名的原理是将要传送的明文通过一种函数运算（Hash）转换成报文摘要，报文摘要加密后与明文一起传送给接受方，接受方将接受的明文产生新的报文摘要与发送方的发来报文摘要解密比较，如果不一致表示明文已被篡改。   \n",
    "### 3.2、算法特点\n",
    "\n",
    "\n",
    "### 3.3、代码实现\n",
    "\n",
    "```python\n",
    "import hashlib\n",
    "\n",
    "str_encrypt = \"123456\"\n",
    "\n",
    "# 对要加密的字符串进行加密\n",
    "sha = hashlib.sha1(str_encrypt.encode())\n",
    "sha.update(str_encrypt.encode(\"utf8\"))\n",
    "value = sha.hexdigest()\n",
    "\n",
    "# 十六进制\n",
    "print(\"十六进制的字符串\",value)\n",
    "```\n",
    "　　十六进制的字符串 7c4a8d09ca3762af61e59520943dc26494f8941b   \n",
    "\n",
    "\n",
    "### 4、HMAC加密\n",
    "### 4.1、算法介绍\n",
    "　　散列信息鉴别码（Hash Message Authentication Code），HMAC加密算法是一种安全的基于加密hash函数和共享密钥的消息认证协议。　　\n",
    "　　实现原理是用公开函数和密钥产生一个固定长度的值作为认证标识，用这个标识鉴别消息的完整性。　　  \n",
    "### 4.2、算法特点\n",
    "\n",
    "\n",
    "### 4.3、代码实现\n",
    "\n",
    "```python\n",
    "import hmac\n",
    "import hashlib\n",
    "\n",
    "str_encrypt = \"123456\"\n",
    "key=\"liing\"\n",
    "# 第一个参数是密钥key，第二个参数是待加密的字符串，第三个参数是hash函数\n",
    "\n",
    "mac = hmac.new(key.encode(encoding=\"utf-8\"),str_encrypt.encode(\"utf8\"),hashlib.md5)\n",
    "\n",
    "value=mac.hexdigest()  # 加密后字符串的十六进制格式\n",
    "\n",
    "# 十六进制\n",
    "print(\"十六进制的字符串\",value)\n",
    "\n",
    "```\n",
    "\n",
    "　　十六进制的字符串 cf521c2724af07de30e0e634b6b46a6c\n",
    "\n",
    "\n",
    "### 5、DES加密\n",
    "　　参考：[python如何实现DES加密](https://www.jb51.net/article/196109.htm) \n",
    "　　　　　[python实现DES加密和解密](https://blog.csdn.net/yuaneuro/article/details/109258590)   \n",
    "　　　　　[DES的Python实现](https://zhuanlan.zhihu.com/p/38231086)   \n",
    "　　　　　[python实现DES加密解密方法](https://www.qb5200.com/article/286074.html)   \n",
    "### 5.1、算法介绍\n",
    "　　数据加密标准（Data Encryption Standard），属于对称加密算法。是一种使用密钥加密的块算法。接口参数有三个：Key、Data、Mode，Key为工作密钥，为8个字节64位，是要被加密或被解密的数据；Mode工作方式：加密或解密。   \n",
    "　　所谓对称性加密，加密和解密密钥相同。对称性加密一般会按照固定长度（8个字节），把待加密字符串分成块。不足一整块可以使用特殊填充字符。  \n",
    "　　常见的加密解密模式有：ECB,CBC,CTR,OFB,CFB,EAX,OPENPGP。   \n",
    "　　常见的填充模式有：'pkcs5','pkcs7','iso10126','ansix923','zero' 类型．   \n",
    "　　**Padding填充：** 以pkcs7填充为例，如果需要加密的数据的字节码长度不是块大小的整数倍就需要填充。比如数据长度是5个字节，DES就需要填充3个chr(3)，即3个‘\\x03’，而AES则需要填充13个chr(13)即13个‘\\r’。如果数据长度是16个字节，恰好是整数倍，则分别额外填充一个块大小的数据，比如DES则需要填充8个'\\x08'，而AES则需要填充16个'\\x10'。  \n",
    "### 5.2、算法特点\n",
    "\n",
    "\n",
    "### 5.3、代码实现\n",
    "　　pyDes 太慢,利用Crypto更快的 DES 加解密。处理20万的数据，pyDEs要用2个小时，太慢了。  \n",
    "　　Crypto改造了一下，处理20万数据40秒左右，效率大大提升。  \n",
    "\n",
    "```python\n",
    "import binascii\n",
    "import base64\n",
    "from Crypto.Cipher import DES\n",
    "# 需要安装 pip install pycryptodome\n",
    "\n",
    "#加密过程    模式： DES.MODE_ECB DES.MODE_CBC DES.MODE_CTR\n",
    "def des_encrypt(secret_key,s):\n",
    "    num = DES.block_size - len(s) % DES.block_size 　　# 需要填充的字符个数\n",
    "    text_pad = (s + num*chr(num)).encode('utf-8') 　　# 填充后的字节串\n",
    "    encryptor = DES.new(secret_key, DES.MODE_CBC, self.iv)\n",
    "    encrypt_data = encryptor.encrypt(text_pad) 　　#对数据进行加密\n",
    "    return base64.b64encode(encrypt_data).decode()\n",
    "\n",
    "#解密过程\n",
    "def des_decrypt(secret_key, s):\n",
    "        data = base64.b64decode(text.encode())\n",
    "        crpytor = DES.new(self.key, self.mode, self.iv)\n",
    "        decrypt_data = crpytor.decrypt(data) #对数据进行解密\n",
    "        res = decrypt_data[:-decrypt_data[-1]].decode()#去除多余字符\n",
    "        return res\n",
    "\n",
    "secret_str = des_encrypt('12345678', 'hello!')\n",
    "print(secret_str)\n",
    "\n",
    "clear_str = des_decrypt('12345678', secret_str)\n",
    "print(clear_str)\n",
    "```\n",
    "\n",
    "b'7c48af7e37ecd280'    \n",
    "b'hello!'   \n",
    "\n",
    "\n",
    "### 5、AES加密\n",
    "　　参考：[AES加密算法的原理详解与实现分析](https://www.jb51.net/article/193493.htm)  \n",
    "### 5.1、算法介绍\n",
    "　　AES,高级加密标准（英语：Advanced Encryption Standard，缩写：AES），又称Rijndael加密法，是美国联邦政府采用的一种区块加密标准。这个标准用来替代原先的DES，已经被多方分析且广为全世界所使用。AES对加密快和密钥的字节数都有一定的要求，区块(加密块)分组长度128位，即16个字节，密钥长度则可以是128，192或256位（即16、24和32个字节）。AES分为几种模式，比如ECB，CBC，CFB、OFB等等，其中最常见的有ECB和CBC。这些模式除了ECB由于没有使用IV（初始向量）而不太安全，其他模式差别并没有太明显。DES中IV长度固定为8个字节，AES中IV长度固定为16个字节，不同的IV加密后的字符串是不同的，加密和解密需要相同的IV。　   \n",
    "#### 5.1.1、ECB模式\n",
    "　　对明文分组，每组明文通过加密算法和密钥位运算得到密文，之后按照顺序将计算所得的密文连在一起即可，各段数据之间互不影响。   \n",
    "\n",
    "#### 5.1.2、CBC模式（使用最多的模式）\n",
    "　　CBC模式需要一个初始化向量iv（和密钥长度相等的字符串），一般通过密钥生成器获取。   \n",
    "　　加密步骤如下：   \n",
    "  \n",
    "+ 首先将数据分组得到D1D2…Dn  \n",
    "+ 第一组数据D1与初始化向量iv位运算的结果进行加密得到第一组密文C1  \n",
    "+ 第二组数据D2与第一组的加密结果C1位运算以后的结果进行加密，得到第二组密文C2  \n",
    "+ 之后的数据以此类推，得到Cn  \n",
    "+ 按顺序连为C1C2C3…Cn即为加密结果。   \n",
    "  \n",
    "　　加密特点：  \n",
    "+ 不容易主动攻击,安全性好于ECB,适合传输长度长的报文,是SSL、IPSec的标准。每个密文块依赖于所有的信息块，明文消息中一个改变会影响所有密文块\n",
    "+ 发送方和接收方都需要知道初始化向量\n",
    "+ 加密过程是串行的，无法被并行化（在解密时，从两个邻接的密文块中即可得到一个平文块。因此，解密过程可以被并行化。）\n",
    "+ 解密时初始化向量必须相同\n",
    "\n",
    "### 5.2、算法特点\n",
    "\n",
    "\n",
    "### 5.3、代码实现\n",
    "#### 5.3.1、ECB加密模式\n",
    "```python\n",
    "import base64\n",
    "from Crypto.Cipher import AES\n",
    "\n",
    "#ECB加密模式\n",
    "\n",
    "import base64\n",
    "from Crypto.Cipher import AES\n",
    "\n",
    "\n",
    "#使用补0方法\n",
    "\n",
    "# # 需要补位，补足为16的倍数\n",
    "def add_to_16(s):\n",
    "    while len(s) % 16 != 0:\n",
    "        s += '\\0'\n",
    "    return str.encode(s)  # 返回bytes\n",
    "\n",
    "# 密钥长度必须为16、24或32位，分别对应AES-128、AES-192和AES-256\n",
    "key = 'abc4567890abc458'\n",
    "# 待加密文本\n",
    "text = 'hello'\n",
    "# 初始化加密器\n",
    "aes = AES.new(add_to_16(key), AES.MODE_ECB)\n",
    "# 加密\n",
    "encrypted_text = str(base64.encodebytes(aes.encrypt(add_to_16(text))), encoding='utf8').replace('\\n', '')\n",
    "# 解密\n",
    "decrypted_text = str(\n",
    "    aes.decrypt(base64.decodebytes(bytes(encrypted_text, encoding='utf8'))).rstrip(b'\\0').decode(\"utf8\"))\n",
    "\n",
    "print('加密值：', encrypted_text)\n",
    "print('解密值：', decrypted_text)\n",
    "```\n",
    "加密值：p3i7p25Ypel2X2yrFG4rCQ==\n",
    "解密值：hello\n",
    "\n",
    "#### 5.3.2、CBC加密模式（一）\n",
    "```python\n",
    "# CBC加密模式\n",
    "import base64\n",
    "from Crypto.Cipher import AES\n",
    "from urllib import parse\n",
    "\n",
    "AES_SECRET_KEY = 'helloBrook2abcde'  # 此处16|24|32个字符\n",
    "IV = 'helloBrook2abcde' \n",
    "\n",
    "\n",
    "# padding算法\n",
    "\n",
    "BS = len(AES_SECRET_KEY)\n",
    "\n",
    "# 填充方案\n",
    "pad = lambda s: s + (BS - len(s) % BS) * chr(BS - len(s) % BS)\n",
    "\n",
    "# 解密时删除填充的值\n",
    "\n",
    "unpad = lambda s: s[0:-ord(s[-1:])]\n",
    "\n",
    "def cryptoEn(string, key, iv):\n",
    "\n",
    "# param string: 原始数据\n",
    "# param key: 密钥\n",
    "# param iv: 向\n",
    "\n",
    "    mode = AES.MODE_CBC\n",
    "\n",
    "    cipher = AES.new(key.encode(\"utf8\"),mode,iv.encode(\"utf8\"))\n",
    "\n",
    "    encrypted = cipher.encrypt(bytes(pad(string), encoding=\"utf8\"))\n",
    "\n",
    "    return base64.b64encode(encrypted).decode(\"utf-8\")\n",
    "\n",
    "\n",
    "#CBC模式的解密代码\n",
    "\n",
    "def cryptoDe(destring, key, iv):\n",
    "\n",
    "# param destring: 需要解密的数据\n",
    "# param key: 密钥\n",
    "# param iv: 向量\n",
    "\n",
    "    mode = AES.MODE_CBC\n",
    "    \n",
    "    decode = base64.b64decode(destring)\n",
    "\n",
    "    cipher = AES.new(key.encode(\"utf8\"),mode,iv.encode(\"utf8\"))\n",
    "\n",
    "    decrypted = cipher.decrypt(decode)\n",
    "\n",
    "    return unpad(decrypted).decode(\"utf-8\")\n",
    "\n",
    "\n",
    "secret_str = cryptoEn('hello', AES_SECRET_KEY,IV)\n",
    "print(secret_str)\n",
    "\n",
    "clear_str = cryptoDe(secret_str.encode(\"utf8\"), AES_SECRET_KEY,IV)\n",
    "print(clear_str)\n",
    "```\n",
    "sqlpZ0AdaRAOQRabchzltQ==\n",
    "hello\n",
    "\n",
    "#### 5.3.3、CBC加密模式（二）\n",
    "```python\n",
    "import base64\n",
    "from Crypto.Cipher import AES\n",
    "from urllib import parse\n",
    "\n",
    "AES_SECRET_KEY = 'helloBrook2abcde'  # 此处16|24|32个字符\n",
    "IV = 'helloBrook2abcde' \n",
    "\n",
    "# padding算法\n",
    "BS = len(AES_SECRET_KEY)\n",
    "pad = lambda s: s + (BS - len(s) % BS) * chr(BS - len(s) % BS)\n",
    "unpad = lambda s: s[0:-ord(s[-1:])]\n",
    "\n",
    "\n",
    "class AES_ENCRYPT(object):\n",
    "    def __init__(self):\n",
    "        self.key = AES_SECRET_KEY\n",
    "        self.mode = AES.MODE_CBC\n",
    "\n",
    "    # 加密函数\n",
    "    def encrypt(self, text):\n",
    "        cryptor = AES.new(self.key.encode(\"utf8\"), self.mode, IV.encode(\"utf8\"))\n",
    "        self.ciphertext = cryptor.encrypt(bytes(pad(text), encoding=\"utf8\"))\n",
    "        # AES加密时候得到的字符串不一定是ascii字符集的，输出到终端或者保存时候可能存在问题，使用base64编码\n",
    "        return base64.b64encode(self.ciphertext).decode(\"utf-8\")\n",
    "\n",
    "    # 解密函数\n",
    "    def decrypt(self, text):\n",
    "        decode = base64.b64decode(text)\n",
    "        cryptor = AES.new(self.key.encode(\"utf8\"), self.mode, IV.encode(\"utf8\"))\n",
    "        plain_text = cryptor.decrypt(decode)\n",
    "        return unpad(plain_text).decode(\"utf-8\")\n",
    "\n",
    "\n",
    "if __name__ == '__main__':\n",
    "    aes_encrypt = AES_ENCRYPT()\n",
    "    text = \"Python\"\n",
    "    e = aes_encrypt.encrypt(text)\n",
    "    d = aes_encrypt.decrypt(e)\n",
    "    print(text)\n",
    "    print(e)\n",
    "    print(d)\n",
    "```\n",
    "待加密字符串：Python\n",
    "加密值：X09JC6IqnsDFp9b9C57cUA==\n",
    "解密值：Python\n",
    "\n",
    "如果字符串包含中文，先对文本转ascii码，将支持中文加密\n",
    "\n",
    "text = base64.b64encode(text.encode('utf-8')).decode('ascii')\n",
    "\n",
    "\n",
    "### 6、RSA加密\n",
    "　　参考：[python RSA加密、解密、签名](https://www.jianshu.com/p/7a4645691c68)  \n",
    "### 6.1、算法介绍\n",
    "　　Rivest-Shamir-Adleman，RSA加密算法是一种非对称加密算法。公钥加密，私钥解密，在公开密钥加密和电子商业中RSA被广泛使用。目前最重要的加密算法！　　  \n",
    "### 6.2、算法特点\n",
    "\n",
    "\n",
    "### 6.3、代码实现\n",
    "\n",
    "\n",
    "\n",
    "\n",
    "\n",
    "\n",
    "\n",
    "### 7、密码生成器\n",
    "　　参考：[python密码生成器的使用](https://www.py.cn/jishu/jichu/29310.html)  \n",
    "### 7.1、算法介绍\n",
    "　　1、随机生成N位密码。换个角度这其实相当于，准备好大写字母集合，小写字母集合，数字集合，特殊字符集合，从中随机挑选N个字符，然后把它们排成一排。您看，这样我们就不能把一般的需求转化为可以通过编程解决的实际问题了吗？  \n",
    "　　2、密码至少要包含一个大写字母，一个小写字母，一个数字，一个特殊字符，并且可以指定密码长度。为了满足这一要求，有一个简单的方法，我们从头开始，把密码放在第一位。大写字母，第二个小写字母，第三个数字，第四个特殊字符，剩下的N-4个字符依次放任意字符。\n",
    "　　3、要解决从字符集中随机取字的问题——我们以前学过random.randint()函数，它可以随机生成一个数字，我们把这个随机数字作为索引去取字符集中取值(字符集合可以是str或list形式)，从而达到随机取字符的目的。  \n",
    "　　4、通过命令行交互接收密码长度相对简单，使用input()。　   　  \n",
    "### 7.2、算法特点\n",
    "\n",
    "\n",
    "### 7.3、代码实现\n",
    "\n",
    "```python\n",
    "import randomchar\n",
    " \n",
    " \n",
    "def generate_password(length):\n",
    "    if length < 4:\n",
    "        raise ValueError('密码至少为 4 位')\n",
    " \n",
    "    random_char = randomchar.RandomChar()\n",
    " \n",
    "    password  = random_char.uppercase()\n",
    "    password += random_char.lowercase()\n",
    "    password += random_char.digit()\n",
    "    password += random_char.special()\n",
    " \n",
    "    count = 5\n",
    "    while count <= length:\n",
    "        password += random_char.anyone()\n",
    "        count += 1\n",
    " \n",
    "    return password\n",
    " \n",
    " \n",
    "password_length = input('请输入密码长度（8～20）：')\n",
    "password_length = int(password_length)\n",
    " \n",
    "if password_length < 8 or password_length > 20:\n",
    "    raise ValueError('密码长度不符')\n",
    " \n",
    "password = generate_password(password_length)\n",
    "print(password)\n",
    "```\n",
    "\n",
    "\n",
    "\n",
    "\n"
   ]
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