Admin: 1 версия

2010-06-01T05:02:02Z

1 версия

в 17:44, 31 мая 2010

2010-05-31T17:44:27Z

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== Basic symmetric encryption example ==



<source lang="java">
import java.security.Security;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
public class MainClass {
public static void main(String[] args) throws Exception {
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
byte[] input = "input123".getBytes();
byte[] keyBytes = new byte[] {
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f };
SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
Cipher cipher = Cipher.getInstance("AES/ECB/NoPadding", "BC");

byte[] cipherText = new byte[input.length];
cipher.init(Cipher.ENCRYPT_MODE, key);

int ctLength = cipher.update(input, 0, input.length, cipherText, 0);
ctLength += cipher.doFinal(cipherText, ctLength);
System.out.println("cipher text: " + new String(cipherText) + " bytes: " + ctLength);
byte[] plainText = new byte[ctLength];
cipher.init(Cipher.DECRYPT_MODE, key);
int ptLength = cipher.update(cipherText, 0, ctLength, plainText, 0);
ptLength += cipher.doFinal(plainText, ptLength);
System.out.println("plain text : " + new String(plainText) + " bytes: " + ptLength);
}
}</source>



== Basic symmetric encryption example with padding ==



<source lang="java">
import java.security.Security;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
public class MainClass {
public static void main(String[] args) throws Exception {
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
byte[] input = "input".getBytes();
byte[] keyBytes = new byte[] { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,
0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f };
SecretKeySpec key = new SecretKeySpec(keyBytes, "AES");
Cipher cipher = Cipher.getInstance("AES/ECB/PKCS7Padding", "BC");
cipher.init(Cipher.ENCRYPT_MODE, key);
byte[] cipherText = new byte[cipher.getOutputSize(input.length)];
int ctLength = cipher.update(input, 0, input.length, cipherText, 0);
ctLength += cipher.doFinal(cipherText, ctLength);
cipher.init(Cipher.DECRYPT_MODE, key);
byte[] plainText = new byte[cipher.getOutputSize(ctLength)];
int ptLength = cipher.update(cipherText, 0, ctLength, plainText, 0);
ptLength += cipher.doFinal(plainText, ptLength);
System.out.println("plain : " + new String(plainText));
}
}</source>



== Basic symmetric encryption example with padding and CBC using DES ==



<source lang="java">
import java.security.Security;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
public class MainClass {
public static void main(String[] args) throws Exception {
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
byte[] input = "input".getBytes();
byte[] keyBytes = new byte[] { 0x01, 0x23, 0x45, 0x67, (byte) 0x89, (byte) 0xab, (byte) 0xcd,
(byte) 0xef };
byte[] ivBytes = new byte[] { 0x07, 0x06, 0x05, 0x04, 0x03, 0x02, 0x01, 0x00 };
SecretKeySpec key = new SecretKeySpec(keyBytes, "DES");
IvParameterSpec ivSpec = new IvParameterSpec(ivBytes);
Cipher cipher = Cipher.getInstance("DES/CBC/PKCS7Padding", "BC");
cipher.init(Cipher.ENCRYPT_MODE, key, ivSpec);
byte[] cipherText = new byte[cipher.getOutputSize(input.length)];
int ctLength = cipher.update(input, 0, input.length, cipherText, 0);
ctLength += cipher.doFinal(cipherText, ctLength);
cipher.init(Cipher.DECRYPT_MODE, key, ivSpec);
byte[] plainText = new byte[cipher.getOutputSize(ctLength)];
int ptLength = cipher.update(cipherText, 0, ctLength, plainText, 0);
ptLength += cipher.doFinal(plainText, ptLength);
System.out.println("plain : " + new String(plainText));
}
}</source>



== Basic symmetric encryption example with padding and ECB using DES ==



<source lang="java">
import java.security.Security;
import javax.crypto.Cipher;
import javax.crypto.spec.SecretKeySpec;
public class MainClass {
public static void main(String[] args) throws Exception {
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
byte[] input = "input".getBytes();
byte[] keyBytes = new byte[] { 0x01, 0x23, 0x45, 0x67, (byte) 0x89, (byte) 0xab, (byte) 0xcd,
(byte) 0xef };
SecretKeySpec key = new SecretKeySpec(keyBytes, "DES");
Cipher cipher = Cipher.getInstance("DES/ECB/PKCS7Padding", "BC");
cipher.init(Cipher.ENCRYPT_MODE, key);
byte[] cipherText = new byte[cipher.getOutputSize(input.length)];
int ctLength = cipher.update(input, 0, input.length, cipherText, 0);
ctLength += cipher.doFinal(cipherText, ctLength);
cipher.init(Cipher.DECRYPT_MODE, key);
byte[] plainText = new byte[cipher.getOutputSize(ctLength)];
int ptLength = cipher.update(cipherText, 0, ctLength, plainText, 0);
ptLength += cipher.doFinal(plainText, ptLength);
System.out.println("plain : " + new String(plainText));
}
}</source>



== Symmetric encryption example with padding and CBC using DES with the initialization vector inline. ==



<source lang="java">
import java.security.Security;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
public class MainClass {
public static void main(String[] args) throws Exception {
Security.addProvider(new org.bouncycastle.jce.provider.BouncyCastleProvider());
byte[] input = "input".getBytes();
byte[] keyBytes = "input123".getBytes();
byte[] ivBytes = "12345123".getBytes();
SecretKeySpec key = new SecretKeySpec(keyBytes, "DES");
IvParameterSpec ivSpec = new IvParameterSpec(new byte[8]);
Cipher cipher = Cipher.getInstance("DES/CBC/PKCS7Padding", "BC");
cipher.init(Cipher.ENCRYPT_MODE, key, ivSpec);
byte[] cipherText = new byte[cipher.getOutputSize(ivBytes.length + input.length)];
int ctLength = cipher.update(ivBytes, 0, ivBytes.length, cipherText, 0);
ctLength += cipher.update(input, 0, input.length, cipherText, ctLength);
ctLength += cipher.doFinal(cipherText, ctLength);
cipher.init(Cipher.DECRYPT_MODE, key, ivSpec);
byte[] buf = new byte[cipher.getOutputSize(ctLength)];
int bufLength = cipher.update(cipherText, 0, ctLength, buf, 0);
bufLength += cipher.doFinal(buf, bufLength);
byte[] plainText = new byte[bufLength - ivBytes.length];
System.arraycopy(buf, ivBytes.length, plainText, 0, plainText.length);
System.out.println("plain : " + new String(plainText));
}
}</source>

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Admin: 1 версия

в 17:44, 31 мая 2010