AG6j1EsN

1import java.io.BufferedReader;
2import java.io.FileReader;
3import java.io.IOException;
4import java.security.GeneralSecurityException;
5import java.security.KeyFactory;
6import java.security.Security;
7import java.security.interfaces.RSAPublicKey;
8import java.security.spec.PKCS8EncodedKeySpec;
9import java.security.spec.X509EncodedKeySpec;
10
11import javax.crypto.Cipher;
12import javax.crypto.SecretKey;
13
14import org.apache.commons.codec.binary.Base64;
15import java.security.interfaces.RSAPrivateKey;
16import org.bouncycastle.util.encoders.Hex;
17 
18
19public class BouncyCastleExample {
20	public static void main(String[] args) throws IOException, GeneralSecurityException {
21		Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
22
23		byte[] input = "test".getBytes();
24		Cipher cipher = Cipher.getInstance("RSA/None/PKCS1Padding");
25	
26		RSAPublicKey key = getPublicKey("C:\\Users\\gszymanowski\\Downloads\\OpenSSL\\bin\\public.pem");
27		
28		cipher.init(Cipher.ENCRYPT_MODE, key);
29		
30		byte[] plainText = cipher.doFinal(input);
31		System.out.println("plain : " + new String(plainText));
32		byte[] encoded = Hex.encode(plainText);
33		System.out.println(new String(encoded));
34		
35		RSAPrivateKey priv = getPrivateKey("C:\\Users\\gszymanowski\\Downloads\\OpenSSL\\bin\\privkey.pem");
36
37		cipher.init(Cipher.DECRYPT_MODE, priv);
38		
39		byte[] result = cipher.doFinal(encoded);
40
41		//System.out.println(new String(result));
42	}
43	
44	 private static String getKey(String filename) throws IOException {
45		    // Read key from file
46		    String strKeyPEM = "";
47		    BufferedReader br = new BufferedReader(new FileReader(filename));
48		    String line;
49		    while ((line = br.readLine()) != null) {
50		        strKeyPEM += line + "\n";
51		    }
52		    br.close();
53		    return strKeyPEM;
54		}
55	   
56	   public static RSAPublicKey getPublicKey(String filename) throws IOException, GeneralSecurityException {
57		    String publicKeyPEM = getKey(filename);
58		    return getPublicKeyFromString(publicKeyPEM);
59		}
60	
61	public static RSAPublicKey getPublicKeyFromString(String key) throws IOException, GeneralSecurityException {
62	    String publicKeyPEM = key;
63	    publicKeyPEM = publicKeyPEM.replace("-----BEGIN PUBLIC KEY-----\n", "");
64	    publicKeyPEM = publicKeyPEM.replace("-----END PUBLIC KEY-----", "");
65	    byte[] encoded = Base64.decodeBase64(publicKeyPEM);
66	    KeyFactory kf = KeyFactory.getInstance("RSA");
67	    RSAPublicKey pubKey = (RSAPublicKey) kf.generatePublic(new X509EncodedKeySpec(encoded));
68	    return pubKey;
69	}
70	
71	public static byte[] encrypt(String message) throws IOException, GeneralSecurityException {
72		byte[] input = message.getBytes();
73		Cipher cipher = Cipher.getInstance("RSA/None/PKCS1Padding");
74	
75		RSAPublicKey key = getPublicKey("C:\\Users\\gszymanowski\\Downloads\\OpenSSL\\bin\\public.pem");
76		
77		cipher.init(Cipher.ENCRYPT_MODE, key);
78		
79		byte[] plainText = cipher.doFinal(input);
80		System.out.println("plain : " + new String(plainText));
81		return plainText;
82	}
83	
84	public static String decrypt(String strToDecrypt, SecretKey key) {
85     try {
86           Cipher cipher = Cipher.getInstance("RSA/None/PKCS1Padding");
87           cipher.init(Cipher.DECRYPT_MODE, key);
88
89           return new String(cipher.doFinal(org.apache.commons.codec.binary.Hex.decodeHex(strToDecrypt.toCharArray())));
90     } catch (Exception e) {
91           System.out.println("Error while decrypting: " + e.toString());
92     }
93     return null;
94	}
95	
96	public static RSAPrivateKey getPrivateKey(String filename) throws IOException, GeneralSecurityException {
97	    String privateKeyPEM = getKey(filename);
98	    return getPrivateKeyFromString(privateKeyPEM);
99	}
100	public static RSAPrivateKey getPrivateKeyFromString(String key) throws IOException, GeneralSecurityException {
101	    String privateKeyPEM = key;
102	    privateKeyPEM = privateKeyPEM.replace("-----BEGIN PRIVATE KEY-----\n", "");
103	    privateKeyPEM = privateKeyPEM.replace("-----END PRIVATE KEY-----", "");
104	    byte[] encoded = Base64.decodeBase64(privateKeyPEM);
105	    KeyFactory kf = KeyFactory.getInstance("RSA");
106	    PKCS8EncodedKeySpec keySpec = new PKCS8EncodedKeySpec(encoded);
107	    RSAPrivateKey privKey = (RSAPrivateKey) kf.generatePrivate(keySpec);
108	    return privKey;
109	}
110
111  
112	
113}