Java与C#秘钥之间的转换

C#的秘钥与Java秘钥的区别

C#使用的是标准的RSA格式，然后将其中的数字base64编码后，生成XML进行存储。

Java中使用的是pkcs8、X.509的公私钥语法，存储的都是相应的JAVA类自动生成的base64字符串

C#私钥样式：

<RSAKeyValue>
  <Modulus>pJlJIR0+G/vs7mhycs0Zd5DbWokMCsLX7Ih373+ljlteRmTm8IHj0Sl8zA26Qu/oAmqh9OFk806zW3TXl90RghSeQhzZBXFHBrTFN4U/o3wPhZBdFazh80bbskrmQ/jmz70qUm3HmGzsb3toxzN6Ehakdo7qP2Kc6aOVTyXrYpk=</Modulus>
  <Exponent>AQAB</Exponent>
  <P>1WKkFg6jlS2eZSVLiH1CK4b9uhr7qE1/L+tPqKQs+PzHX4eiZXnyAlQ+kgGmL7n1wR1RWNuiYnDZUetmTogaDQ==</P>
  <Q>xXhsuEnNJNQcQHEVTPZoulbMbTV1VZIDQ1zjG8fvu8sv6IBYcR5+EsC8n3/6RkW8/iCJDzxE++VHzhoSQSoDvQ==</Q>
  <DP>zr/rcn+umd0Aisnu/Ik48smxz39TdIfaAwkBPsoL1Re+6V2WyLG1/fG4SmmUpsuMRRdt+SWdmbnzpr7peo++hQ==</DP>
  <DQ>MWi2W04sBEEGaKFi4QTuo2FAeTrdBvIn2t0M/lCCjYyDijtC5drpVKvhBk+xQZAFf9iIMsWzxQtTciBX3PI0SQ==</DQ>
  <InverseQ>wGEfA3LWM4NHgRnXDqwwOUs3OtqWK0tsJPPcFMci+Bcgy96JpFTCr7bubXHMu14bdopCWUann2d3UuwEpvP+</InverseQ>
  <D>mK3TRtMwRJb33OGnn9OeFumYfy92qxi3X6Hq1o6qDBW2qkd4bImfv+ni6AinyOVuaadt2Y+lq4dKGcCVJzoZvPm1VKxD2y7xKa8/vEbPRiRTt0qnPq9T7UJkpDsiXf/zOMfWdjc3uA1bPnQ65RWHSJ7zAE+Gd7xnyCE5MEyijLE=</D>
</RSAKeyValue>

C#公钥样式：

<RSAKeyValue>
 <Modulus>pJlJIR0+G/vs7mhycs0Zd5DbWokMCsLX7Ih373+ljlteRmTm8IHj0Sl8zA26Qu/oAmqh9OFk806zW3TXl90RghSeQhzZBXFHBrTFN4U/o3wPhZBdFazh80bbskrmQ/jmz70qUm3HmGzsb3toxzN6Ehakdo7qP2Kc6aOVTyXrYpk=</Modulus>
  <Exponent>AQAB</Exponent>
</RSAKeyValue>

Java私钥样式：

-----BEGIN PRIVATE KEY-----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-----END PRIVATE KEY-----

Java公钥样式：

-----BEGIN PUBLIC KEY-----
MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQCgpdJdqmIGX2V9/CF9wfHo4V9X
J6OLiIzsHgoFW3+nD0M4gdDr/Y6oGoll9Fta2pKpawCEyZhpPqtF0kYrD8fr4TTs
TvLyhNJEzpUGqSGjR4SddWYquaL5hc5Uy5HBV9KDYILp8jhe1TdRSSH8NI+40LSH
BVqYjcN0G+sPrdxHbwIDAQAB
-----END PUBLIC KEY-----

Java代码实现秘钥之间的转化

import java.math.BigInteger;
import java.nio.charset.Charset;
import java.security.KeyFactory;
import java.security.PrivateKey;
import java.security.PublicKey;
import java.security.interfaces.RSAPrivateCrtKey;
import java.security.interfaces.RSAPublicKey;
import java.security.spec.RSAPrivateCrtKeySpec;
import java.security.spec.RSAPublicKeySpec;
import java.util.Base64;

/**
 * C#秘钥与Java互转
 */
public class CSharpOrJavaUtil {

    /**
     * C#私钥转换成java私钥
     */
    public static String privateKeyFromXml(String privateKeyXml) {
        privateKeyXml = privateKeyXml.replaceAll("\r", "").replaceAll("\n", "");

        KeyFactory keyFactory;
        try {
            String modulusXml = privateKeyXml.substring(privateKeyXml.indexOf("<Modulus>") + 9, privateKeyXml.indexOf("</Modulus>"));
            BigInteger modulus = new BigInteger(1, Base64.getDecoder().decode(modulusXml));

            String publicExponentXml = privateKeyXml.substring(privateKeyXml.indexOf("<Exponent>") + 10, privateKeyXml.indexOf("</Exponent>"));
            BigInteger publicExponent = new BigInteger(1, Base64.getDecoder().decode(publicExponentXml));

            String privateExponentXml = privateKeyXml.substring(privateKeyXml.indexOf("<D>") + 3, privateKeyXml.indexOf("</D>"));
            BigInteger privateExponent = new BigInteger(1, Base64.getDecoder().decode(privateExponentXml));

            String primePXml = privateKeyXml.substring(privateKeyXml.indexOf("<P>") + 3, privateKeyXml.indexOf("</P>"));
            BigInteger primeP = new BigInteger(1, Base64.getDecoder().decode(primePXml));

            String primeQXml = privateKeyXml.substring(privateKeyXml.indexOf("<Q>") + 3, privateKeyXml.indexOf("</Q>"));
            BigInteger primeQ = new BigInteger(1, Base64.getDecoder().decode(primeQXml));

            String primeExponentPXml = privateKeyXml.substring(privateKeyXml.indexOf("<DP>") + 4, privateKeyXml.indexOf("</DP>"));
            BigInteger primeExponentP = new BigInteger(1, Base64.getDecoder().decode(primeExponentPXml));

            String primeExponentQXml = privateKeyXml.substring(privateKeyXml.indexOf("<DQ>") + 4, privateKeyXml.indexOf("</DQ>"));
            BigInteger primeExponentQ = new BigInteger(1, Base64.getDecoder().decode(primeExponentQXml));

            String crtCoefficientXml = privateKeyXml.substring(privateKeyXml.indexOf("<InverseQ>") + 10, privateKeyXml.indexOf("</InverseQ>"));
            BigInteger crtCoefficient = new BigInteger(1, Base64.getDecoder().decode(crtCoefficientXml));

            RSAPrivateCrtKeySpec rsaPriKey = new RSAPrivateCrtKeySpec(modulus, publicExponent, privateExponent, primeP, primeQ, primeExponentP, primeExponentQ, crtCoefficient);

            keyFactory = KeyFactory.getInstance("RSA");
            PrivateKey privateKey = keyFactory.generatePrivate(rsaPriKey);
            byte[] bytes = Base64.getEncoder().encode(privateKey.getEncoded());
            return new String(bytes, Charset.forName("utf-8"));
        } catch (Exception e) {
            System.err.println(e.toString());
        }
        return null;
    }

    /**
     * C#公钥转换成java公钥
     */
    public static String publicKeyFromXml(String publicKeyXml) {
        KeyFactory keyFactory;
        publicKeyXml = publicKeyXml.replaceAll("\r", "").replaceAll("\n", "");
        try {
            String modulusXml = publicKeyXml.substring(publicKeyXml.indexOf("<Modulus>") + 9, publicKeyXml.indexOf("</Modulus>"));
            BigInteger modulus = new BigInteger(1, Base64.getDecoder().decode(modulusXml));

            String exponentXml = publicKeyXml.substring(publicKeyXml.indexOf("<Exponent>") + 10, publicKeyXml.indexOf("</Exponent>"));
            BigInteger publicExponent = new BigInteger(1, Base64.getDecoder().decode(exponentXml));

            RSAPublicKeySpec rsaPubKey = new RSAPublicKeySpec(modulus, publicExponent);
            keyFactory = KeyFactory.getInstance("RSA");
            PublicKey publicKey = keyFactory.generatePublic(rsaPubKey);
            byte[] bytes = Base64.getEncoder().encode(publicKey.getEncoded());
            return new String(bytes, Charset.forName("utf-8"));
        } catch (Exception e) {
            System.err.println(e.toString());
            return null;
        }
    }

    /**
     * java私钥转换成C#私钥
     */
    public static String privateKeyToXml(RSAPrivateCrtKey privateKey) {

        String modulusBase64 = Base64.getEncoder().encodeToString(privateKey.getModulus().toByteArray());
        String modulus = modulusBase64.replace("\r", "").replace("\n", "");

        String exponentBase64 = Base64.getEncoder().encodeToString(privateKey.getPublicExponent().toByteArray());
        String exponent = exponentBase64.replace("\r", "").replace("\n", "");

        String pBase64 = Base64.getEncoder().encodeToString(privateKey.getPrimeP().toByteArray());
        String p = pBase64.replace("\r", "").replace("\n", "");

        String qBase64 = Base64.getEncoder().encodeToString(privateKey.getPrimeQ().toByteArray());
        String q = qBase64.replace("\r", "").replace("\n", "");

        String dpBase64 = Base64.getEncoder().encodeToString(privateKey.getPrimeExponentP().toByteArray());
        String dp = dpBase64.replace("\r", "").replace("\n", "");

        String dqBase64 = Base64.getEncoder().encodeToString(privateKey.getPrimeExponentQ().toByteArray());
        String dq = dqBase64.replace("\r", "").replace("\n", "");

        String dBase64 = Base64.getEncoder().encodeToString(privateKey.getPrivateExponent().toByteArray());
        String d = dBase64.replace("\r", "").replace("\n", "");
        
        String inverseQBase64 = Base64.getEncoder().encodeToString(privateKey.getCrtCoefficient().toByteArray());
        String inverseQ = inverseQBase64.replace("\r", "").replace("\n", "");

        StringBuilder stringBuilder = new StringBuilder();
        stringBuilder.append("<RSAKeyValue>\n");
        stringBuilder.append("<Modulus>").append(modulus).append("</Modulus>\n");
        stringBuilder.append("<Exponent>").append(exponent).append("</Exponent>\n");
        stringBuilder.append("<P>").append(p).append("</P>\n");
        stringBuilder.append("<Q>").append(q).append("</Q>\n");
        stringBuilder.append("<DP>").append(dp).append("</DP>\n");
        stringBuilder.append("<DQ>").append(dq).append("</DQ>\n");
        stringBuilder.append("<InverseQ>").append(inverseQ).append("</InverseQ>\n");
        stringBuilder.append("<D>").append(d).append("</D>\n");
        stringBuilder.append("</RSAKeyValue>");
        return stringBuilder.toString();
    }

    /**
     * java公钥转换成C#公钥
     */
    public static String publicKeyToXml(RSAPublicKey publicKey) {
        String modulusBase64 = Base64.getEncoder().encodeToString(publicKey.getModulus().toByteArray());
        String modulus = modulusBase64.replace("\r", "").replace("\n", "");

        String exponentBase64 = Base64.getEncoder().encodeToString(publicKey.getPublicExponent().toByteArray());
        String exponent = exponentBase64.replace("\r", "").replace("\n", "");

        StringBuilder stringBuilder = new StringBuilder();
        stringBuilder.append("<RSAKeyValue>\n");
        stringBuilder.append("<Modulus>").append(modulus).append("</Modulus>\n");
        stringBuilder.append("<Exponent>").append(exponent).append("</Exponent>\n");
        stringBuilder.append("</RSAKeyValue>");
        return stringBuilder.toString();
    }

    public static void main(String[] args) {
        String privateXml =
                "<RSAKeyValue>\n" +
                "  <Modulus>pJlJIR0+G/vs7mhycs0Zd5DbWokMCsLX7Ih373+ljlteRmTm8IHj0Sl8zA26Qu/oAmqh9OFk806zW3TXl90RghSeQhzZBXFHBrTFN4U/o3wPhZBdFazh80bbskrmQ/jmz70qUm3HmGzsb3toxzN6Ehakdo7qP2Kc6aOVTyXrYpk=</Modulus>\n" +
                "  <Exponent>AQAB</Exponent>\n" +
                "  <P>1WKkFg6jlS2eZSVLiH1CK4b9uhr7qE1/L+tPqKQs+PzHX4eiZXnyAlQ+kgGmL7n1wR1RWNuiYnDZUetmTogaDQ==</P>\n" +
                "  <Q>xXhsuEnNJNQcQHEVTPZoulbMbTV1VZIDQ1zjG8fvu8sv6IBYcR5+EsC8n3/6RkW8/iCJDzxE++VHzhoSQSoDvQ==</Q>\n" +
                "  <DP>zr/rcn+umd0Aisnu/Ik48smxz39TdIfaAwkBPsoL1Re+6V2WyLG1/fG4SmmUpsuMRRdt+SWdmbnzpr7peo++hQ==</DP>\n" +
                "  <DQ>MWi2W04sBEEGaKFi4QTuo2FAeTrdBvIn2t0M/lCCjYyDijtC5drpVKvhBk+xQZAFf9iIMsWzxQtTciBX3PI0SQ==</DQ>\n" +
                "  <InverseQ>wGEfA3LWM4NHgRnXDqwwOUs3OtqWK0tsJPPcFMci+Bcgy96JpFTCr7bubXHMu14bdopCWUann2d3UuwEpvP+</InverseQ>\n" +
                "  <D>mK3TRtMwRJb33OGnn9OeFumYfy92qxi3X6Hq1o6qDBW2qkd4bImfv+ni6AinyOVuaadt2Y+lq4dKGcCVJzoZvPm1VKxD2y7xKa8/vEbPRiRTt0qnPq9T7UJkpDsiXf/zOMfWdjc3uA1bPnQ65RWHSJ7zAE+Gd7xnyCE5MEyijLE=</D>\n" +
                "</RSAKeyValue>";
        System.out.println(privateKeyFromXml(privateXml));
    }

}