java/php/c#版rsa签名以及验签实现

本文为转载,请转载请注明地址: 原文地址为        http://xw-z1985.iteye.com/blog/1837376

在开放平台领域，需要给isv提供sdk，签名是Sdk中需要提供的功能之一。由于isv使用的开发语言不是单一的，因此sdk需要提供多种语言的版 本。譬如java、php、c#。另外，在电子商务尤其是支付领域，对安全性的要求比较高，所以会采用非对称密钥RSA

本文主要介绍如何基于java、php、c#在客户端使用rsa签名，然后在服务端使用Java验签。

1. 基于openssl生成RSA公私钥对

a）从网上下载openssl工具:http://www.slproweb.com/products/Win32OpenSSL.html

b）生成私钥

进入到openssl的bin目录下，执行以下命令：

openssl genrsa -out rsa_private_key.pem 1024

会在bin目录下看到新生成的私钥文件rsa_private_key.pem，文件内容如下：

     -----BEGIN RSA PRIVATE KEY-----
     MIICXgIBAAKBgQDtd1lKsX6ylsAEWFi7E/ut8krJy9PQ7sGYKhIm9TvIdZiq5xzy
     aw8NOLzKZ1k486MePYG4tSuoaxSbwuPLwVUzYFvnUZo7aWCIGKn16UWTM4nxc/+d
     wce+bhcKrlLbTWi8l580LTE7GxclTh8z7gHq59ivhaoGbK7FNxlUfB4TSQIDAQAB
     AoGBAIgTk0x1J+hI8KHMypPxoJCOPoMi1S9uEewTd7FxaB+4G5Mbuv/Dj62A7NaD
     oKI9IyUqE9L3ppvtOLMFXCofkKU0p4j7MEJdZ+CjVvgextkWa80nj/UZiM1oOL6Y
     HwH4ZtPtY+pFCTK1rdn3+070qBB9tnVntbN/jq0Ld7f0t7UNAkEA9ryI0kxJL9Pu
     pO9NEeWuCUo4xcl9x/M9+mtkfY3VoDDDV1E/eUjmoTfANYwrjcddiQrO0MLyEdoo
     tiLpN77qOwJBAPZhtv/+pqMVTrLxWnVKLZ4ZVTPPgJQQkFdhWwYlz7oKzB3VbQRt
     /jLFXUyCN2eCP7rglrXnaz7AYBftF0ajHEsCQQDDNfkeQULqN0gpcDdOwKRIL1Pp
     kHgWmWlg1lTETVJGEi6Kx/prL/VgeiZ1dzgCTUjAoy9r1cEFxM/PAqH3+/F/AkEA
     zsTCp6Q2hLblDRewKq7OCdiIwKpr5dbgy/RQR6CD7EYTdxYeH5GPu1wXKJY/mQae
     JV9GG/LS9h7MhkfbONS6cQJAdBEb5vloBDLcSQFDQO/VZ9SKFHCmHLXluhhIizYK
     Gzgf3OXEGNDSAC3qy+ZTnLd3N5iYrVbK52UoiLOLhhNMqA==
     -----END RSA PRIVATE KEY-----  

c)生成公钥

在bin目录下，执行以下命令：

openssl rsa -in rsa_private_key.pem -pubout -out rsa_public_key.pem

会在bin目录下看到新生成的公钥文件rsa_public_key.pem，文件内容如下：

 -----BEGIN PUBLIC KEY-----
 MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDtd1lKsX6ylsAEWFi7E/ut8krJ
 y9PQ7sGYKhIm9TvIdZiq5xzyaw8NOLzKZ1k486MePYG4tSuoaxSbwuPLwVUzYFvn
 UZo7aWCIGKn16UWTM4nxc/+dwce+bhcKrlLbTWi8l580LTE7GxclTh8z7gHq59iv
 haoGbK7FNxlUfB4TSQIDAQAB
 -----END PUBLIC KEY-----

2. 客户端签名

2.1 java版签名实现

 /**
  * rsa签名  * @param content
  *            待签名的字符串
  * @param privateKey
  *            rsa私钥字符串
  * @param charset
  *            字符编码
  * @return 签名结果
  * @throws Exception
  *             签名失败则抛出异常
  */
 public String rsaSign(String content, String privateKey, String charset) throws SignatureException {
     try {
         PrivateKey priKey = getPrivateKeyFromPKCS8("RSA", new ByteArrayInputStream(privateKey.getBytes()));

         Signature signature = Signature.getInstance("SHA1WithRSA");
         signature.initSign(priKey);
         if (StringUtils.isEmpty(charset)) {
             signature.update(content.getBytes());
         } else {
             signature.update(content.getBytes(charset));
         }

         byte[] signed = signature.sign();
         return new String(Base64.encodeBase64(signed));
     } catch (Exception e) {
         throw new SignatureException("RSAcontent = " + content + "; charset = " + charset, e);
     }
 }

 public PrivateKey getPrivateKeyFromPKCS8(String algorithm, InputStream ins) throws Exception {
     if (ins == null || StringUtils.isEmpty(algorithm)) {
         return null;
     }

     KeyFactory keyFactory = KeyFactory.getInstance(algorithm);
     byte[] encodedKey = StreamUtil.readText(ins).getBytes();
     encodedKey = Base64.decodeBase64(encodedKey);
     return keyFactory.generatePrivate(new PKCS8EncodedKeySpec(encodedKey));
 }

注意：参数privateKey是Pem私钥文件中去除头（-----BEGIN RSA PRIVATE KEY-----）和尾（-----END RSA PRIVATE KEY-----）以及换行符后的字符串。

如果签名报以下错误：

java.security.spec.InvalidKeySpecException: java.security.InvalidKeyException: IOException : algid parse error, not a sequence

则说明rsa私钥的格式不是pksc8格式，需要使用以下命令转换一下：

openssl pkcs8 -topk8 -inform PEM -in rsa_private_key.pem -outform PEM -nocrypt

然后再提取去除头和尾以及换行符后字符串作为java版用的rsa私钥

2.2 php签名实现

 function sign($content, $rsaPrivateKeyPem) {
         $priKey = file_get_contents($rsaPrivateKeyPem);
     $res = openssl_get_privatekey($priKey);
         openssl_sign($content, $sign, $res);
     openssl_free_key($res);
     $sign = base64_encode($sign);
     return $sign;
 }

注意：$rsaPrivateKeyPem为pem私钥文件路径

2.3 c#签名实现(引用了国外某位仁兄的方案)

     using System;
     using System.Text;
     using System.Security.Cryptography;
     using System.Web;
     using System.IO;  

     namespace Aop.Api.Util
     {
         /// <summary>
         /// RSA签名工具类。
         /// </summary>
         public class RSAUtil
         {  

             public static string RSASign(string data, string privateKeyPem)
             {
                 RSACryptoServiceProvider rsaCsp = LoadCertificateFile(privateKeyPem);
                 byte[] dataBytes = Encoding.UTF8.GetBytes(data);
                 byte[] signatureBytes = rsaCsp.SignData(dataBytes, "SHA1");
                 return Convert.ToBase64String(signatureBytes);
             }  

             private static byte[] GetPem(string type, byte[] data)
             {
                 string pem = Encoding.UTF8.GetString(data);
                 string header = String.Format("-----BEGIN {0}-----\\n", type);
                 string footer = String.Format("-----END {0}-----", type);
                 int start = pem.IndexOf(header) + header.Length;
                 int end = pem.IndexOf(footer, start);
                 string base64 = pem.Substring(start, (end - start));
                 return Convert.FromBase64String(base64);
             }  

             private static RSACryptoServiceProvider LoadCertificateFile(string filename)
             {
                 using (System.IO.FileStream fs = System.IO.File.OpenRead(filename))
                 {
                     byte[] data = new byte[fs.Length];
                     byte[] res = null;
                     fs.Read(data, , data.Length);
                     if (data[] != 0x30)
                     {
                         res = GetPem("RSA PRIVATE KEY", data);
                     }
                     try
                     {
                         RSACryptoServiceProvider rsa = DecodeRSAPrivateKey(res);
                         return rsa;
                     }
                     catch (Exception ex)
                     {
                     }
                     return null;
                 }
             }  

             private static RSACryptoServiceProvider DecodeRSAPrivateKey(byte[] privkey)
             {
                 byte[] MODULUS, E, D, P, Q, DP, DQ, IQ;  

                 // --------- Set up stream to decode the asn.1 encoded RSA private key ------
                 MemoryStream mem = new MemoryStream(privkey);
                 BinaryReader binr = new BinaryReader(mem);  //wrap Memory Stream with BinaryReader for easy reading
                 byte bt = ;
                 ushort twobytes = ;
                 int elems = ;
                 try
                 {
                     twobytes = binr.ReadUInt16();
                     if (twobytes == 0x8130) //data read as little endian order (actual data order for Sequence is 30 81)
                         binr.ReadByte();    //advance 1 byte
                     else if (twobytes == 0x8230)
                         binr.ReadInt16();    //advance 2 bytes
                     else
                         return null;  

                     twobytes = binr.ReadUInt16();
                     if (twobytes != 0x0102) //version number
                         return null;
                     bt = binr.ReadByte();
                     if (bt != 0x00)
                         return null;  

                     //------ all private key components are Integer sequences ----
                     elems = GetIntegerSize(binr);
                     MODULUS = binr.ReadBytes(elems);  

                     elems = GetIntegerSize(binr);
                     E = binr.ReadBytes(elems);  

                     elems = GetIntegerSize(binr);
                     D = binr.ReadBytes(elems);  

                     elems = GetIntegerSize(binr);
                     P = binr.ReadBytes(elems);  

                     elems = GetIntegerSize(binr);
                     Q = binr.ReadBytes(elems);  

                     elems = GetIntegerSize(binr);
                     DP = binr.ReadBytes(elems);  

                     elems = GetIntegerSize(binr);
                     DQ = binr.ReadBytes(elems);  

                     elems = GetIntegerSize(binr);
                     IQ = binr.ReadBytes(elems);  

                     // ------- create RSACryptoServiceProvider instance and initialize with public key -----
                     CspParameters CspParameters = new CspParameters();
                     CspParameters.Flags = CspProviderFlags.UseMachineKeyStore;
                     RSACryptoServiceProvider RSA = new RSACryptoServiceProvider(, CspParameters);
                     RSAParameters RSAparams = new RSAParameters();
                     RSAparams.Modulus = MODULUS;
                     RSAparams.Exponent = E;
                     RSAparams.D = D;
                     RSAparams.P = P;
                     RSAparams.Q = Q;
                     RSAparams.DP = DP;
                     RSAparams.DQ = DQ;
                     RSAparams.InverseQ = IQ;
                     RSA.ImportParameters(RSAparams);
                     return RSA;
                 }
                 catch (Exception ex)
                 {
                     return null;
                 }
                 finally
                 {
                     binr.Close();
                 }
             }  

             private static int GetIntegerSize(BinaryReader binr)
             {
                 byte bt = ;
                 byte lowbyte = 0x00;
                 byte highbyte = 0x00;
                 int count = ;
                 bt = binr.ReadByte();
                 if (bt != 0x02)     //expect integer
                     return ;
                 bt = binr.ReadByte();  

                 if (bt == 0x81)
                     count = binr.ReadByte();    // data size in next byte
                 else
                     if (bt == 0x82)
                     {
                         highbyte = binr.ReadByte(); // data size in next 2 bytes
                         lowbyte = binr.ReadByte();
                         byte[] modint = { lowbyte, highbyte, 0x00, 0x00 };
                         count = BitConverter.ToInt32(modint, );
                     }
                     else
                     {
                         count = bt;     // we already have the data size
                     }  

                 while (binr.ReadByte() == 0x00)
                 {   //remove high order zeros in data
                     count -= ;
                 }
                 binr.BaseStream.Seek(-, SeekOrigin.Current);       //last ReadByte wasn't a removed zero, so back up a byte
                 return count;
             }
         }
     }  

注：privateKeyPem为私钥文件路径

3. 服务端java验签

     /**
          * rsa验签
          *
          * @param content 被签名的内容
          * @param sign 签名后的结果
          * @param publicKey rsa公钥
          * @param charset 字符集
          * @return 验签结果
          * @throws SignatureException 验签失败，则抛异常
          */
         boolean doCheck(String content, String sign, String publicKey, String charset) throws SignatureException {
             try {
                 PublicKey pubKey = getPublicKeyFromX509("RSA", new ByteArrayInputStream(publicKey.getBytes()));  

                 Signature signature = Signature.getInstance("SHA1WithRSA");
                 signature.initVerify(pubKey);
                 signature.update(getContentBytes(content, charset));
                 return signature.verify(Base64.decodeBase64(sign.getBytes()));
             } catch (Exception e) {
                 throw new SignatureException("RSA验证签名[content = " + content + "; charset = " + charset
                                              + "; signature = " + sign + "]发生异常!", e);
             }
         }  

         private PublicKey getPublicKeyFromX509(String algorithm, InputStream ins) throws NoSuchAlgorithmException {
             try {
                 KeyFactory keyFactory = KeyFactory.getInstance(algorithm);  

                 StringWriter writer = new StringWriter();
                 StreamUtil.io(new InputStreamReader(ins), writer);
                 byte[] encodedKey = writer.toString().getBytes();  

                 // 先base64解码
                 encodedKey = Base64.decodeBase64(encodedKey);
                 return keyFactory.generatePublic(new X509EncodedKeySpec(encodedKey));
             } catch (IOException ex) {
                 // 不可能发生
             } catch (InvalidKeySpecException ex) {
                 // 不可能发生
             }
             return null;
         }  

         private byte[] getContentBytes(String content, String charset) throws UnsupportedEncodingException {
             if (StringUtil.isEmpty(charset)) {
                 return content.getBytes();
             }  

             return content.getBytes(charset);
         }  

注意：参数publicKey是Pem公钥文件中去除头（-----BEGIN RSA PRIVATE KEY-----）和尾（-----END RSA PRIVATE KEY-----）以及换行符后的字符串。