Seed128 문자열 암호화/복호화

SeedString Class

package seed;

public class SeedString extends Seed {

/**

* <pre>

* Seed128 문자열 암호화

* </pre>

* 

* @param plainText

* @return

*/

public byte[] encrypt(final String plainText) {

byte[] byteIV = { (byte) 0x26, (byte) 0x8D, (byte) 0x66, (byte) 0xA7, (byte) 0x35, (byte) 0xA8, (byte) 0x1A, (byte) 0x81, (byte) 0x6F, (byte) 0xBA, (byte) 0xD9, (byte) 0xFA, (byte) 0x36, (byte) 0x16, (byte) 0x25, (byte) 0x01 };

int[] seedKey = new int[Seed.NoRoundKeys];

Seed.SeedRoundKey(seedKey, Seed.key);

byte[] pbPlain = addPadding(plainText.getBytes(), Seed.SeedBlockSize);

byte[] pbCipher = new byte[pbPlain.length];

byte[] sSource = new byte[Seed.SeedBlockSize];

byte[] sTarget = new byte[Seed.SeedBlockSize];

int rt = pbPlain.length / Seed.SeedBlockSize;

for (int j = 0; j < rt; j++) {

System.arraycopy(pbPlain, (j * Seed.SeedBlockSize), sSource, 0, Seed.SeedBlockSize);

// CBC 운영모드

Seed.exclusiveOR(sSource, byteIV);

Seed.SeedEncrypt(sSource, seedKey, sTarget);

byteIV = sTarget;

System.arraycopy(sTarget, 0, pbCipher, (j * Seed.SeedBlockSize), sTarget.length);

}

return pbCipher;

}

/**

* <pre>

* Seed128 문자열 복호화

* </pre>

* 

* @param encryptBytes

* @return

*/

public String decrypt(byte[] encryptBytes) {

byte[] byteIV = { (byte) 0x26, (byte) 0x8D, (byte) 0x66, (byte) 0xA7, (byte) 0x35, (byte) 0xA8, (byte) 0x1A, (byte) 0x81, (byte) 0x6F, (byte) 0xBA, (byte) 0xD9, (byte) 0xFA, (byte) 0x36, (byte) 0x16, (byte) 0x25, (byte) 0x01 };

int[] seedKey = new int[Seed.NoRoundKeys];

Seed.SeedRoundKey(seedKey, Seed.key);

byte decryptBytes[] = new byte[encryptBytes.length];

byte sSource[] = new byte[Seed.SeedBlockSize];

byte sTarget[] = new byte[Seed.SeedBlockSize];

int rt = encryptBytes.length / Seed.SeedBlockSize;

for (int j = 0; j < rt; j++) {

System.arraycopy(encryptBytes, (j * Seed.SeedBlockSize), sSource, 0, Seed.SeedBlockSize);

Seed.SeedDecrypt(sSource, seedKey, sTarget);

// CBC 운영모드

Seed.exclusiveOR(sTarget, byteIV);

System.arraycopy(sSource, 0, byteIV, 0, Seed.SeedBlockSize);

System.arraycopy(sTarget, 0, decryptBytes, (j * Seed.SeedBlockSize), Seed.SeedBlockSize);

}

decryptBytes = removePadding(decryptBytes, Seed.SeedBlockSize);

return new String(decryptBytes);

}

/**

* 패킷내 정의된 필드의 길이가 남을때 패딩개수로 채운다

* PKCSPadding

*

* @param b : 대상 바이트 배열

* @param blockSize : 블럭 길이

*/

private byte[] addPadding(byte[] source, int blockSize) {

int paddingCnt = source.length % blockSize;

byte[] paddingResult = null;

if (paddingCnt != 0) {

paddingResult = new byte[source.length + (blockSize - paddingCnt)];

System.arraycopy(source, 0, paddingResult, 0, source.length);

// 패딩해야 할 갯수 - 1 (마지막을 제외)까지 0x00 값을 추가한다.

int addPaddingCnt = blockSize - paddingCnt;

for (int i = 0; i < addPaddingCnt; i++) {

paddingResult[source.length + i] = (byte) addPaddingCnt;

}

} else {

paddingResult = source;

}

return paddingResult;

}

/**

* 패킷내 패딩된 패딩개수를 제거한다.

* PKCSPadding

*

* @param source

* @param blockSize

* @return

*/

private byte[] removePadding(byte[] source, int blockSize) {

byte[] paddingResult = null;

boolean isPadding = false;

// 패딩 된 count를 찾는다.

int lastValue = source[source.length - 1];

if (0 < lastValue && lastValue < (blockSize - 1)) {

for (int i = 1; i <= lastValue; i++) {

if (source[source.length - i] != lastValue) {

isPadding = false;

break;

}

isPadding = true;

}

} else {

isPadding = false;

}

if (isPadding) {

paddingResult = new byte[source.length - lastValue];

System.arraycopy(source, 0, paddingResult, 0, paddingResult.length);

} else {

paddingResult = source;

}

return paddingResult;

}

}

Main

public static void main(String[] args) {

String password = "010-222-2222-123010-222-2222-123010-222-2222-123";

String key = "0123456789abcdef";

SeedString seed = new SeedString();

seed.setKey(key.getBytes());

// Encrypt

byte[] pbCipher = seed.encrypt(password);

System.out.println(new String(pbCipher).toString());

// Decrypt

String data = seed.decrypt(pbCipher);

System.out.println(data);

}

참조) http://revf.tistory.com/entry/%EC%A0%95%EB%B3%B4%EB%B3%B4%ED%98%B8-%EC%A7%84%ED%9D%A5%EC%9B%90-SEED-%EC%95%94%ED%98%B8%ED%99%94