node.js - 求Md5withRsa php 、python、或者nodejs的實現，或者給講講原理？

客戶介面是使用的java實現，驗證使用的md5withrsa,拆開看都理解，放到一塊就懵逼了，求講解！！！！
附java的實現方式：

package main;import java.security.KeyFactory;import java.security.KeyPair;import java.security.NoSuchAlgorithmException;import java.security.PrivateKey;import java.security.PublicKey;import java.security.Signature;import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;import java.security.spec.PKCS8EncodedKeySpec;import java.security.spec.X509EncodedKeySpec;import java.security.SecureRandom;public class main {        /**     * 產生秘鑰     */    public static void makeKey()    {        String KEY_ALGORITHM = "rsa";        java.security.KeyPairGenerator keygen;        try {            keygen = java.security.KeyPairGenerator                    .getInstance(KEY_ALGORITHM );            SecureRandom secrand = new SecureRandom();            secrand.setSeed("tmriPayment".getBytes()); // 初始化隨機產生器            keygen.initialize(1024);            KeyPair keys = keygen.genKeyPair();            RSAPublicKey pubkey = (RSAPublicKey) keys.getPublic();            RSAPrivateKey prikey = (RSAPrivateKey) keys.getPrivate();            String pubKeyStr=  Base64Util.encodeBase64(pubkey.getEncoded());//得到公開金鑰 並做base64編碼            String priKeyStr=  Base64Util.encodeBase64(prikey.getEncoded());//得到私密金鑰 並做base64編碼                        System.out.println("公開金鑰:"+ pubKeyStr);            System.out.println("私密金鑰:"+ priKeyStr);                    } catch (NoSuchAlgorithmException e) {            // TODO Auto-generated catch block            e.printStackTrace();        } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }    }        /**     * 加密     * @return     */    public static String encodeData()    {                try {                        byte[] data = "fdfdfsdfdfd".getBytes();            String privateKey = "MIICXAIBAAKBgQDOF3dzQpPVIvHrx2qwszcv9Cw5XhCEyuRTy+HDPD684NSGGGnL"+                    "34cLc1BCEjlT3v9H81SigvSUDB++YbMcZOrRFT+MAt22yi98BcRP60vgVixfTCCI"+                    "lc39b6G6I6ac5BUfOKwdUKNUnCLvcojshmtGezcEYGocMziOIwXIdBXErQIDAQAB"+                    "AoGANlycRovuQM9J7v6YFun/Cagnri4wv0ZhefUSpRQUHHBVvtVbuspIbe3J4tO5"+                    "yXTN86Ws0n0mlJKqIObWfwvjoDADNeEWFXUI5YKyEnpnvvZwTo1JjrDy8QJpGe94"+                    "yNebfGLKyZtIc/zLq9sFboyqNCtn2hu7IsG2g4SGe9BFcsUCQQDnrc6yXG6jmFC/"+                    "7HFqXj5NtQc72vYbIjf32yG8W1D1j3ghZZwtUkIa8g3WMxFrYW9DFMzTDi3/mPSd"+                    "1A9OG89DAkEA47oFZj6xf7gzDbHDdKX/S9ehjQjP2q6V7SYXnhdEwioxjJpj9qrP"+                    "SKQg8A9m4nUl2FXJ2spxApotHoKHqTGFTwJBAIkcohGJBqmnQVL0mgK7l9/hXVCd"+                    "O72/OKRlecfBu1449H2/ZvijkB/mVS4Jtyt31KM8siPOZoa4fTzS/ePaLYUCQDHj"+                    "LY2hjFbzblPArpXeS5g8y8pOtOIuPu/t2Vyrskdq4OHxbJa8Ap7iPcj5RsuzaDAF"+                    "UywYDzvHtLyrUbbR/2cCQGbbIWDLPtzHzI7QumtabHq9M5zUgvtXDksnOltcEDSX"+                    "aBoGSbpRcPcGFfFMY+fd/kdmEambYn+270DNHPvqljU=";            byte[] keyBytes;            keyBytes = Base64Util.decodeBase64(privateKey);            PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);            KeyFactory keyFactory = KeyFactory.getInstance("RSA");            PrivateKey priKey = keyFactory.generatePrivate(pkcs8KeySpec);            Signature signature = Signature.getInstance("MD5withRSA");            signature.initSign(priKey);            signature.update(data);//data為要產生簽名的來源資料位元組數組            return Base64Util.encodeBase64(Base64Util.encodeBase64(signature.sign()).getBytes());                    } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }//對私密金鑰做base64解碼                return "";    }            /**     * 解密     * @return     */    public static Boolean decodeData(String msg)    {        String publicKey = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDMrfAeCg5zyHJKs269vMywoMYwKWGfBbk31K44g0ZLg8YN4c9jOH4hyAYkhN5mWY69Q8Sb82OAlxBXMY1zQshKk6kzZGOrYDQOt/bvVg6kPdf9IgtWky4YaCVSR2C0zYCviz+pHXJrbTeyVVLmbaxsr2lEjamBoDcfM1uE9hj83QIDAQAB";                try {        byte[] data = "fdfdfsdfdfd".getBytes();        byte[] publicKey1 = Base64Util.decodeBase64(publicKey);//對提供的公開金鑰做base64解碼                byte[] sign = Base64Util.decodeBase64( new String(Base64Util.decodeBase64(msg)));//簽名需要做二次base64解碼                X509EncodedKeySpec keySpec = new X509EncodedKeySpec(publicKey1);        KeyFactory keyFactory = KeyFactory.getInstance("RSA");        PublicKey pubKey = keyFactory.generatePublic(keySpec);        Signature signature = Signature.getInstance("MD5withRSA");        signature.initVerify(pubKey);        signature.update(data);        return signature.verify(sign);        } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }//對私密金鑰做base64解碼                return false;    }            public static void main(String[] args) throws Exception {        // TODO Auto-generated method stub        //makeKey();                String msg = encodeData();        //System.out.println(msg);                //String msg = "ZlBGVnVXQm1YVjhhWDhGbVVYV24raEJzRVB1WFAycUhKdVIwbGl3azY5T2VKWHBkMDlpL1U5aGYwcEVvK1h0M0RNMFNsRTNQM1pYazFyT25xblZwTStRZmJhVGVPUXBsZ0ozZVFKemFnaWt5dzNvUXRNZC81RGQ4RGlSR3pqUmRhOFd2OCt1ekRiakZBdWtqeGg3Y1plTEdTT2ppQ08rcFVqOUQxZXh6ZG1VPQ==";        //Boolean data = decodeData(msg);        //System.out.println(data);        }}

回複內容：

客戶介面是使用的java實現，驗證使用的md5withrsa,拆開看都理解，放到一塊就懵逼了，求講解！！！！
附java的實現方式：

package main;import java.security.KeyFactory;import java.security.KeyPair;import java.security.NoSuchAlgorithmException;import java.security.PrivateKey;import java.security.PublicKey;import java.security.Signature;import java.security.interfaces.RSAPrivateKey;import java.security.interfaces.RSAPublicKey;import java.security.spec.PKCS8EncodedKeySpec;import java.security.spec.X509EncodedKeySpec;import java.security.SecureRandom;public class main {        /**     * 產生秘鑰     */    public static void makeKey()    {        String KEY_ALGORITHM = "rsa";        java.security.KeyPairGenerator keygen;        try {            keygen = java.security.KeyPairGenerator                    .getInstance(KEY_ALGORITHM );            SecureRandom secrand = new SecureRandom();            secrand.setSeed("tmriPayment".getBytes()); // 初始化隨機產生器            keygen.initialize(1024);            KeyPair keys = keygen.genKeyPair();            RSAPublicKey pubkey = (RSAPublicKey) keys.getPublic();            RSAPrivateKey prikey = (RSAPrivateKey) keys.getPrivate();            String pubKeyStr=  Base64Util.encodeBase64(pubkey.getEncoded());//得到公開金鑰 並做base64編碼            String priKeyStr=  Base64Util.encodeBase64(prikey.getEncoded());//得到私密金鑰 並做base64編碼                        System.out.println("公開金鑰:"+ pubKeyStr);            System.out.println("私密金鑰:"+ priKeyStr);                    } catch (NoSuchAlgorithmException e) {            // TODO Auto-generated catch block            e.printStackTrace();        } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }    }        /**     * 加密     * @return     */    public static String encodeData()    {                try {                        byte[] data = "fdfdfsdfdfd".getBytes();            String privateKey = "MIICXAIBAAKBgQDOF3dzQpPVIvHrx2qwszcv9Cw5XhCEyuRTy+HDPD684NSGGGnL"+                    "34cLc1BCEjlT3v9H81SigvSUDB++YbMcZOrRFT+MAt22yi98BcRP60vgVixfTCCI"+                    "lc39b6G6I6ac5BUfOKwdUKNUnCLvcojshmtGezcEYGocMziOIwXIdBXErQIDAQAB"+                    "AoGANlycRovuQM9J7v6YFun/Cagnri4wv0ZhefUSpRQUHHBVvtVbuspIbe3J4tO5"+                    "yXTN86Ws0n0mlJKqIObWfwvjoDADNeEWFXUI5YKyEnpnvvZwTo1JjrDy8QJpGe94"+                    "yNebfGLKyZtIc/zLq9sFboyqNCtn2hu7IsG2g4SGe9BFcsUCQQDnrc6yXG6jmFC/"+                    "7HFqXj5NtQc72vYbIjf32yG8W1D1j3ghZZwtUkIa8g3WMxFrYW9DFMzTDi3/mPSd"+                    "1A9OG89DAkEA47oFZj6xf7gzDbHDdKX/S9ehjQjP2q6V7SYXnhdEwioxjJpj9qrP"+                    "SKQg8A9m4nUl2FXJ2spxApotHoKHqTGFTwJBAIkcohGJBqmnQVL0mgK7l9/hXVCd"+                    "O72/OKRlecfBu1449H2/ZvijkB/mVS4Jtyt31KM8siPOZoa4fTzS/ePaLYUCQDHj"+                    "LY2hjFbzblPArpXeS5g8y8pOtOIuPu/t2Vyrskdq4OHxbJa8Ap7iPcj5RsuzaDAF"+                    "UywYDzvHtLyrUbbR/2cCQGbbIWDLPtzHzI7QumtabHq9M5zUgvtXDksnOltcEDSX"+                    "aBoGSbpRcPcGFfFMY+fd/kdmEambYn+270DNHPvqljU=";            byte[] keyBytes;            keyBytes = Base64Util.decodeBase64(privateKey);            PKCS8EncodedKeySpec pkcs8KeySpec = new PKCS8EncodedKeySpec(keyBytes);            KeyFactory keyFactory = KeyFactory.getInstance("RSA");            PrivateKey priKey = keyFactory.generatePrivate(pkcs8KeySpec);            Signature signature = Signature.getInstance("MD5withRSA");            signature.initSign(priKey);            signature.update(data);//data為要產生簽名的來源資料位元組數組            return Base64Util.encodeBase64(Base64Util.encodeBase64(signature.sign()).getBytes());                    } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }//對私密金鑰做base64解碼                return "";    }            /**     * 解密     * @return     */    public static Boolean decodeData(String msg)    {        String publicKey = "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDMrfAeCg5zyHJKs269vMywoMYwKWGfBbk31K44g0ZLg8YN4c9jOH4hyAYkhN5mWY69Q8Sb82OAlxBXMY1zQshKk6kzZGOrYDQOt/bvVg6kPdf9IgtWky4YaCVSR2C0zYCviz+pHXJrbTeyVVLmbaxsr2lEjamBoDcfM1uE9hj83QIDAQAB";                try {        byte[] data = "fdfdfsdfdfd".getBytes();        byte[] publicKey1 = Base64Util.decodeBase64(publicKey);//對提供的公開金鑰做base64解碼                byte[] sign = Base64Util.decodeBase64( new String(Base64Util.decodeBase64(msg)));//簽名需要做二次base64解碼                X509EncodedKeySpec keySpec = new X509EncodedKeySpec(publicKey1);        KeyFactory keyFactory = KeyFactory.getInstance("RSA");        PublicKey pubKey = keyFactory.generatePublic(keySpec);        Signature signature = Signature.getInstance("MD5withRSA");        signature.initVerify(pubKey);        signature.update(data);        return signature.verify(sign);        } catch (Exception e) {            // TODO Auto-generated catch block            e.printStackTrace();        }//對私密金鑰做base64解碼                return false;    }            public static void main(String[] args) throws Exception {        // TODO Auto-generated method stub        //makeKey();                String msg = encodeData();        //System.out.println(msg);                //String msg = "ZlBGVnVXQm1YVjhhWDhGbVVYV24raEJzRVB1WFAycUhKdVIwbGl3azY5T2VKWHBkMDlpL1U5aGYwcEVvK1h0M0RNMFNsRTNQM1pYazFyT25xblZwTStRZmJhVGVPUXBsZ0ozZVFKemFnaWt5dzNvUXRNZC81RGQ4RGlSR3pqUmRhOFd2OCt1ekRiakZBdWtqeGg3Y1plTEdTT2ppQ08rcFVqOUQxZXh6ZG1VPQ==";        //Boolean data = decodeData(msg);        //System.out.println(data);        }}

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