RSA非对称加密简析-java
1 非对称加密算法
1.1 概述
1976年，美国学者Dime和Henman为解决信息公开传送和密钥管理问题，提出一种新的密钥交换协议，允许在不安全的媒体上的通讯双方交换信息，安全地达成一致的密钥，这就是“公开密钥系统”。
与对称加密算法不同，非对称加密算法需要两个密钥：公开密钥（publickey）和私有密钥（privatekey）。公开密钥与私有密钥是一对，如果用公开密钥对数据进行加密，只有用对应的私有密钥才能解密；如果用私有密钥对数据进行加密，那么只有用对应的公开密钥才能解密。因为加密和解密使用的是两个不同的密钥，所以这种算法叫作非对称加密算法。
1.2 加密流程
如下图所示，甲乙之间使用非对称加密的方式完成了重要信息的安全传输。
非对称加密工作过程简要示意图
1、乙方生成一对密钥（公钥和私钥）并将公钥向其它方公开。
2、得到该公钥的甲方使用该密钥对机密信息进行加密后再发送给乙方。
3、乙方再用自己保存的另一把专用密钥（私钥）对加密后的信息进行解密。乙方只能用其专用密钥（私钥）解密由对应的公钥加密后的信息。
在传输过程中，即使攻击者截获了传输的密文，并得到了乙的公钥，也无法破解密文，因为只有乙的私钥才能解密密文。
同样，如果乙要回复加密信息给甲，那么需要甲先公布甲的公钥给乙用于加密，甲自己保存甲的私钥用于解密。
2 RSA加密算法
2.1 概述
RSA是目前最有影响力和最常用的公钥加密算法，它能够抵抗到目前为止已知的绝大多数密码攻击，已被ISO推荐为公钥数据加密标准。
RSA公开密钥密码体制。所谓的公开密钥密码体制就是使用不同的加密密钥与解密密钥，是一种“由已知加密密钥推导出解密密钥在计算上是不可行的”密码体制。
在公开密钥密码体制中，加密密钥（即公开密钥）PK是公开信息，而解密密钥（即秘密密钥）SK是需要保密的。加密算法E和解密算法D也都是公开的。虽然解密密钥SK是由公开密钥PK决定的，但却不能根据PK计算出SK。
正是基于这种理论，1978年出现了著名的RSA算法，它通常是先生成一对RSA 密钥，其中之一是保密密钥，由用户保存；另一个为公开密钥，可对外公开，甚至可在网络服务器中注册。为提高保密强度，RSA密钥至少为500位长，一般推荐使用1024位。这就使加密的计算量很大。为减少计算量，在传送信息时，常采用传统加密方法与公开密钥加密方法相结合的方式，即信息采用改进的DES或IDEA对话密钥加密，然后使用RSA密钥加密对话密钥和信息摘要。对方收到信息后，用不同的密钥解密并可核对信息摘要。
RSA算法是第一个能同时用于加密和数字签名的算法，也易于理解和操作。RSA是被研究得最广泛的公钥算法，从提出到现今的三十多年里，经历了各种攻击的考验，逐渐为人们接受，普遍认为是目前最优秀的公钥方案之一。
2.2 算法实现过程
1. 随意选择两个大的质数p和q，p不等于q，计算N=pq。
2. 根据欧拉函数，不大于N且与N互质的整数個数為(p-1)(q-1)。
3. 选择一个整数e与(p-1)(q-1)互质，并且e小于(p-1)(q-1)。
4. 用以下这个公式计算d：d× e ≡ 1 (mod (p-1)(q-1))。
5. 将p和q的记录销毁。
以上内容中，(N,e)是公钥，(N,d)是私钥。
2.3 算法缺点
1）产生密钥很麻烦，受到素数产生技术的限制，因而难以做到一次一密。
2）安全性，RSA的安全性依赖于大数的因子分解，但并没有从理论上证明破译RSA的难度与大数分解难度等价，而且密码学界多数人士倾向于因子分解不是NP问题。
3）速度太慢，由于RSA 的分组长度太大，为保证安全性，n 至少也要 600 bits以上，使运算代价很高，尤其是速度较慢，较对称密码算法慢几个数量级；且随着大数分解技术的发展，这个长度还在增加，不利于数据格式的标准化。
2.4 java代码实现加解密
1 package xin.dreaming.rsa; 2 3 import java.io.ByteArrayOutputStream; 4 import java.io.UnsupportedEncodingException; 5 import java.security.Key; 6 import java.security.KeyFactory; 7 import java.security.KeyPair; 8 import java.security.KeyPairGenerator; 9 import java.security.NoSuchAlgorithmException; 10 import java.security.interfaces.RSAPrivateKey; 11 import java.security.interfaces.RSAPublicKey; 12 import java.security.spec.PKCS8EncodedKeySpec; 13 import java.security.spec.X509EncodedKeySpec; 14 import java.util.HashMap; 15 import java.util.Map; 16 17 import javax.crypto.Cipher; 18 19 import org.bouncycastle.util.encoders.Base64; 20 21 /** 22 * Rsa工具类 23 * 24 * @author DREAMING.XIN 25 * 26 */ 27 public abstract class RsaUtils { 28 /** 29 * 生成公钥私钥对，使用默认模长1024。 30 * 31 * @return Object[] : 0:公钥( RSAPublicKey )，1:私钥( RSAPrivateKey ) 32 */ 33 34 private static final int DEFAULT_KEY_LEN = 2048; 35 36 public static Map<String, String> genKeyPair() { 37 return genKeyPair(DEFAULT_KEY_LEN); 38 39 } 40 41 /** 42 * 指定模长生成公私钥对 43 * 44 * @param modulus 45 * @return 46 */ 47 public static Map<String, String> genKeyPair(int modulus) { 48 KeyPairGenerator keyPairGen; 49 try { 50 keyPairGen = KeyPairGenerator.getInstance("RSA"); 51 keyPairGen.initialize(modulus); 52 KeyPair keyPair = keyPairGen.generateKeyPair(); 53 54 Map<String, String> keyMaps = new HashMap<String, String>(); 55 RSAPublicKey publicKey = (RSAPublicKey) keyPair.getPublic(); 56 keyMaps.put("publicKey", new String(Base64.encode(publicKey.getEncoded()))); 57 RSAPrivateKey privateKey = (RSAPrivateKey) keyPair.getPrivate(); 58 keyMaps.put("privateKey", new String(Base64.encode(privateKey.getEncoded()))); 59 60 return keyMaps; 61 } catch (NoSuchAlgorithmException e) { 62 throw new RuntimeException(e); 63 } 64 } 65 66 /** 67 * 公钥加密 68 * 69 * @param publicKeyBytes 70 * @param data 71 * @param modulus 72 * 公钥模长，范围512-2048。 73 * @return 74 */ 75 public static byte[] encryptByPublicKey(byte[] publicKeyBytes, byte[] data, int modulus) { 76 try { 77 // RSA最大加密明文大小 78 int maxEncryptBlock = modulus / 8 - 11; 79 80 X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(publicKeyBytes); 81 KeyFactory keyFactory = KeyFactory.getInstance("RSA"); 82 Key publicK = keyFactory.generatePublic(x509KeySpec); 83 Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm()); 84 cipher.init(Cipher.ENCRYPT_MODE, publicK); 85 int inputLen = data.length; 86 ByteArrayOutputStream out = new ByteArrayOutputStream(); 87 int offSet = 0; 88 byte[] cache; 89 int i = 0; 90 while (inputLen - offSet > 0) { 91 if (inputLen - offSet > maxEncryptBlock) { 92 cache = cipher.doFinal(data, offSet, maxEncryptBlock); 93 } else { 94 cache = cipher.doFinal(data, offSet, inputLen - offSet); 95 } 96 out.write(cache, 0, cache.length); 97 i++; 98 offSet = i * maxEncryptBlock; 99 } 100 byte[] encryptedData = out.toByteArray(); 101 out.close(); 102 return encryptedData; 103 } catch (Exception e) { 104 throw new RuntimeException(e); 105 } 106 107 } 108 109 /** 110 * 公钥加密，密钥模长使用默认长度1024。 111 * 112 * @param publicKeyBytes 113 * 公钥RSAPublicKey getEncoded() 114 * @param data 115 * 要加密的字节数组 116 */ 117 public static byte[] encryptByPublicKey(byte[] publicKeyBytes, byte[] data) { 118 return encryptByPublicKey(publicKeyBytes, data, DEFAULT_KEY_LEN); 119 } 120 121 /** 122 * 公钥解密 123 * 124 * @param publicKeyBytes 125 * 公钥RSAPublicKey getEncoded() 126 * @param encryptedData 127 * 被(私钥)加密过的字节数组 128 * @param modulus 129 * 模长，范围512-2048 130 * @return 131 */ 132 public static byte[] decryptByPublicKey(byte[] publicKeyBytes, byte[] encryptedData, int modulus) { 133 // RSA最大解密密文大小 134 int maxDecryptBlock = modulus / 8; 135 try { 136 X509EncodedKeySpec x509KeySpec = new X509EncodedKeySpec(publicKeyBytes); 137 KeyFactory keyFactory = KeyFactory.getInstance("RSA"); 138 Key publicK = keyFactory.generatePublic(x509KeySpec); 139 Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm()); 140 cipher.init(Cipher.DECRYPT_MODE, publicK); 141 int inputLen = encryptedData.length; 142 ByteArrayOutputStream out = new ByteArrayOutputStream(); 143 int offSet = 0; 144 byte[] cache; 145 int i = 0; 146 // 对数据分段解密 147 while (inputLen - offSet > 0) { 148 if (inputLen - offSet > maxDecryptBlock) { 149 cache = cipher.doFinal(encryptedData, offSet, maxDecryptBlock); 150 } else { 151 cache = cipher.doFinal(encryptedData, offSet, inputLen - offSet); 152 } 153 out.write(cache, 0, cache.length); 154 i++; 155 offSet = i * maxDecryptBlock; 156 } 157 byte[] decryptedData = out.toByteArray(); 158 out.close(); 159 return decryptedData; 160 } catch (Exception e) { 161 throw new RuntimeException(e); 162 } 163 } 164 165 /** 166 * 公钥解密，默认模长1024 167 * 168 * @param publicKeyBytes 169 * 公钥RSAPublicKey getEncoded() 170 * @param encryptedData 171 * 被(私钥)加密过的字节数组 172 */ 173 public static byte[] decryptByPublicKey(byte[] publicKeyBytes, byte[] encryptedData) { 174 return decryptByPublicKey(publicKeyBytes, encryptedData, DEFAULT_KEY_LEN); 175 } 176 177 /** 178 * 私钥加密 179 * 180 * @param privateKeyBytes 181 * 私钥RSAPrivateKey getEncoded() 182 * @param data 183 * 要加密的字节数组 184 * @param modulus 185 * 模长，范围512-2048。 186 */ 187 public static byte[] encryptByPrivateKey(byte[] privateKeyBytes, byte[] data, int modulus) { 188 try { 189 // RSA最大加密明文大小 190 int maxEncryptBlock = modulus / 8 - 11; 191 192 PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(privateKeyBytes); 193 KeyFactory keyFactory = KeyFactory.getInstance("RSA"); 194 Key privateK = keyFactory.generatePrivate(pkcs8KeySpec); 195 Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm()); 196 cipher.init(Cipher.ENCRYPT_MODE, privateK); 197 int inputLen = data.length; 198 ByteArrayOutputStream out = new ByteArrayOutputStream(); 199 int offSet = 0; 200 byte[] cache; 201 int i = 0; 202 while (inputLen - offSet > 0) { 203 if (inputLen - offSet > maxEncryptBlock) { 204 cache = cipher.doFinal(data, offSet, maxEncryptBlock); 205 } else { 206 cache = cipher.doFinal(data, offSet, inputLen - offSet); 207 } 208 out.write(cache, 0, cache.length); 209 i++; 210 offSet = i * maxEncryptBlock; 211 } 212 byte[] encryptedData = out.toByteArray(); 213 out.close(); 214 return encryptedData; 215 } catch (Exception e) { 216 throw new RuntimeException(e); 217 } 218 } 219 220 /** 221 * 私钥加密，默认模长1024。 222 * 223 * @param privateKeyBytes 224 * 私钥RSAPrivateKey getEncoded() 225 * @param data 226 * 要加密的字节数组 227 */ 228 public static byte[] encryptByPrivateKey(byte[] privateKeyBytes, byte[] data) { 229 return encryptByPrivateKey(privateKeyBytes, data, DEFAULT_KEY_LEN); 230 } 231 232 /** 233 * 私钥解密 234 * 235 * @param privateKeyBytes 236 * 私钥RSAPrivateKey getEncoded() 237 * @param encryptedData 238 * 被(公钥)加密过的字节数组 239 * @param modulus 240 * 模长，范围512-2048 241 */ 242 public static byte[] decryptByPrivateKey(byte[] privateKeyBytes, byte[] encryptedData, int modulus) { 243 try { 244 // RSA最大解密密文大小 245 int maxDecryptBlock = modulus / 8; 246 247 PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(privateKeyBytes); 248 KeyFactory keyFactory = KeyFactory.getInstance("RSA"); 249 Key privateK = keyFactory.generatePrivate(pkcs8KeySpec); 250 Cipher cipher = Cipher.getInstance(keyFactory.getAlgorithm()); 251 cipher.init(Cipher.DECRYPT_MODE, privateK); 252 int inputLen = encryptedData.length; 253 ByteArrayOutputStream out = new ByteArrayOutputStream(); 254 int offSet = 0; 255 byte[] cache; 256 int i = 0; 257 while (inputLen - offSet > 0) { 258 if (inputLen - offSet > maxDecryptBlock) { 259 cache = cipher.doFinal(encryptedData, offSet, maxDecryptBlock); 260 } else { 261 cache = cipher.doFinal(encryptedData, offSet, inputLen - offSet); 262 } 263 out.write(cache, 0, cache.length); 264 i++; 265 offSet = i * maxDecryptBlock; 266 } 267 byte[] decryptedData = out.toByteArray(); 268 out.close(); 269 return decryptedData; 270 } catch (Exception e) { 271 throw new RuntimeException(e); 272 } 273 } 274 275 /** 276 * 私钥解密，默认模长1024。 277 * 278 * @param privateKeyBytes 279 * 私钥RSAPrivateKey getEncoded() 280 * @param encryptedData 281 * 被(公钥)加密过的字节数组 282 */ 283 public static byte[] decryptByPrivateKey(byte[] privateKeyBytes, byte[] encryptedData) { 284 return decryptByPrivateKey(privateKeyBytes, encryptedData, DEFAULT_KEY_LEN); 285 } 286 287 public static void main(String[] args) throws UnsupportedEncodingException { 288 // 加密原串 289 String value = "DREAMING.XIN"; 290 System.out.println("加密原串 ： "); 291 System.out.println(value); 292 System.out.println("------------------------------------------------------------------------------------------"); 293 // 生成公私钥对 294 Map<String, String> genKeyPair = genKeyPair(); 295 296 System.out.println("自行生成公私钥对： "); 297 System.out.println(genKeyPair); 298 System.out.println("------------------------------------------------------------------------------------------"); 299 byte[] encryptByPublicKey = encryptByPublicKey(Base64.decode(genKeyPair.get("publicKey").getBytes("utf-8")), 300 value.getBytes()); 301 302 // 3、Base64编码 303 byte[] encode = Base64.encode(encryptByPublicKey); 304 305 System.out.println("最终加密结果： "); 306 String sign = new String(encode, "utf-8"); 307 System.out.println(new String(encode, "utf-8")); 308 System.out.println("------------------------------------------------------------------------------------------"); 309 310 // 1、签名密文->Base64解码->RSA解密 311 byte[] signCipherArr = decryptByPrivateKey(Base64.decode(genKeyPair.get("privateKey").getBytes("utf-8")), 312 Base64.decode(sign.getBytes("utf-8"))); 313 System.out.println("解密结果： "); 314 System.out.println(new String (signCipherArr)); 315 System.out.println("------------------------------------------------------------------------------------------"); 316 317 } 318 }
输出结果：
加密原串 ： DREAMING.XIN ------------------------------------------------------------------------------------------ 自行生成公私钥对： {publicKey=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAkmRw1oug/LBmpkRsubsKoeEBQvGeRfUTMX8fTEuLJqKuWfHkB6HJ/08xf/BYhbL+GrUFk5DR/lbJdnD9SEx0ZDZHecrjj262T67izwf7d+rB3o7z5w/3Pk3p3Ye6Ns7SdGM6D8O6InUK4mQFSBKQhw25BqPzUQKb4DY/S+I2OAx1/qVB56Na+if5H9ttP8nhVVnQZXheTPh5Say0+ySFEBb1i2sxJQuwFLbtA9RkKNFSSB2+4sBrn5fRmemu6OGToR/WQ8KFa96+u9X2t41HPxa7dTF+g9btkEMWwbiXkPatjD9JaNXKKrueIQoDt/FKonUZQ0AafSs8r/xsrb4pfwIDAQAB, privateKey=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} ------------------------------------------------------------------------------------------ 最终加密结果： YmGXP+nSAY23ENUryid4zdE6KRAfFGhQWPJ4NAM1odZIEZCh5BbOtw437E85TdzABNE+NTDVogq+AI8WfAiD0yUpDukdRrZMb/IwG5k7xCgsVo0Tgt2SiH9bZFkvMaIIWH6d90muVtA/dyGHPSk/WmdgSl3QCcsZ3JAzMeadZwtL685eBhJD6hwXwKLfQj1OQBlLH3R9D5gBNGf36RHyi20LteTOKIR9lvMQPGbsnvspqi7t3xo5ajLpeuCr9azEovP0UFiiaxrkGLYMG2YM91r7JXUCn2gtVuDnXPFVVfOj84mN51229UJwQWBZe0BGPLSpROmOUZeWj2gjvuyqGg== ------------------------------------------------------------------------------------------ 解密结果： DREAMING.XIN ------------------------------------------------------------------------------------------
2.5 java代码实现加签验签
1 package xin.dreaming.rsa; 2 3 import org.apache.commons.codec.binary.Base64; 4 5 import javax.crypto.Cipher; 6 import java.io.ByteArrayInputStream; 7 import java.security.KeyFactory; 8 import java.security.PrivateKey; 9 import java.security.PublicKey; 10 import java.security.Signature; 11 import java.security.cert.Certificate; 12 import java.security.cert.CertificateFactory; 13 import java.security.spec.PKCS8EncodedKeySpec; 14 15 /** 16 * 17 * @author DREAMING.XIN 18 * 19 */ 20 public class RSAUtil { 21 22 private static final String CHARSET = "UTF-8"; 23 24 private static final String algorithm = "SHA256withRSA"; 25 26 /** 27 * 网联请求报文签名 28 * 29 * @param privateKey 30 * 机构私钥字符串 31 * @param content 32 * 签名原文 33 * @return 签名密文 34 * @throws Exception 35 */ 36 public static String sign(String privateKey, String content) throws Exception { 37 Signature signature = Signature.getInstance(algorithm); 38 signature.initSign(convertPrivateKey(privateKey)); 39 signature.update(content.getBytes(CHARSET)); 40 return Base64.encodeBase64String(signature.sign()); 41 } 42 43 /** 44 * 网联返回报文验签 45 * 46 * @param publicKey 47 * 网联公钥字符串 48 * @param content 49 * 验签原文报文 50 * @param signStr 51 * 网联返回签名字符串 52 * @return 验签结果 53 * @throws Exception 54 */ 55 public static boolean vertify(String publicKey, String content, String signStr) throws Exception { 56 Signature signature = Signature.getInstance(algorithm); 57 signature.initVerify(convertPublicKey(publicKey)); 58 signature.update(content.getBytes(CHARSET)); 59 return signature.verify(Base64.decodeBase64(signStr.getBytes(CHARSET))); 60 } 61 62 /** 63 * 对称密钥公钥加密 64 * 65 * @param publicKey 66 * 网联公钥字符串 67 * @param content 68 * 密钥原文 69 * @return 加密密文 70 * @throws Exception 71 */ 72 public static String encryptByPublicKey(String publicKey, String content) throws Exception { 73 String result = null; 74 try { 75 Cipher cipher = cipher = Cipher.getInstance("RSA"); 76 cipher.init(Cipher.ENCRYPT_MODE, convertPublicKey(publicKey)); 77 byte[] encoded = cipher.doFinal(content.getBytes(CHARSET)); 78 result = Base64.encodeBase64String(encoded); 79 } catch (Exception e) { 80 81 } 82 return result; 83 } 84 85 /** 86 * 对称密钥密文解密 87 * 88 * @param privateKey 89 * 机构私钥字符串 90 * @param content 91 * 网联对称密钥密文 92 * @return 对称密钥明文 93 * @throws Exception 94 */ 95 public static String decryptByPrivateKey(String privateKey, String content) throws Exception { 96 String result = null; 97 try { 98 Cipher cipher = cipher = Cipher.getInstance("RSA"); 99 cipher.init(Cipher.DECRYPT_MODE, convertPrivateKey(privateKey)); 100 byte[] encoded = cipher.doFinal(Base64.decodeBase64(content.getBytes(CHARSET))); 101 result = new String(encoded, CHARSET); 102 } catch (Exception e) { 103 } 104 return result; 105 } 106 107 public static PrivateKey convertPrivateKey(String keyStr) throws Exception { 108 PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(Base64.decodeBase64(keyStr.getBytes(CHARSET))); 109 KeyFactory keyFactory = KeyFactory.getInstance("RSA"); 110 return keyFactory.generatePrivate(keySpec); 111 } 112 113 public static PublicKey convertPublicKey(String keyStr) throws Exception { 114 CertificateFactory certificateFactory = CertificateFactory.getInstance("X509"); 115 Certificate certificate = certificateFactory 116 .generateCertificate(new ByteArrayInputStream(Base64.decodeBase64(keyStr.getBytes(CHARSET)))); 117 return certificate.getPublicKey(); 118 } 119 120 public static void main(String[] args) throws Exception { 121 // 获取私钥 122 String privatekey = CertConfig.PrivateKey; 123 String publicKey = CertConfig.PublicKeyZ; 124 125 String sign = sign(privatekey, "DREAMING.XIN"); 126 127 System.out.println("加签结果："+sign); 128 129 boolean vertify = vertify(publicKey,"DREAMING.XIN",sign); 130 131 System.out.println("验签结果： "+vertify); 132 } 133 134 }
密钥java类：
1 package xin.dreaming.rsa; 2 3 public class CertConfig { 4 5 public static final String PrivateKey ="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"; 6 //签名私钥 7 //public static final String PrivateKey ="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"; 8 //验签公钥 9 public static final String PublicKey ="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"; 10 //验签公钥 11 public static final String PublicKeyZ ="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"; 12 13 //铭感信息加密 14 public static final String MGJMKEY = "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"; 15 }
输出结果：
加签结果：fbolWDixTffN2oeMSpAUkbDvQ3ZXNeEUPgGOgQ3boCTIft34kIA8LtSwRMD+uAbKSk6vZffDb2Zro7IDGhS8lv35Bz23zs9j04GMB4d55EnjqjyRQAQer8fTujKMPHa2JUPjlUau6wjJaK50A8+TysC7Qq4uz69T0iXtTJPvFxwjCeXL0fShIuD4UQwJkQk7Mqqvzdy71dPs94EobMVEX84lSkfTwZKCwAR58NbYdgWWGKcwbU/N+riU6NyiCVr1rj+j9LqUrgW0HHDfp8hNcRm1lluGgk7BrjD7ZBpdYwuhbA1v2IGEsdhYVyMHdFpg6Ta3uoHoCJRJhtMp1Hw0qw== 验签结果： true
说明：
一般rsa加密解密，加签验签都会与BASE64编码或url编码结合使用。
参考：
1、https://baike.baidu.com/item/RSA%E7%AE%97%E6%B3%95/263310?fr=aladdin
版权声明：本文为xq1314原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接和本声明。