public void setPrvKey(byte[] x, byte[] p, byte[] q, byte[] g) throws Exception {
DSAPrivateKeySpec dsaPrivKeySpec =
new DSAPrivateKeySpec(
new BigInteger(x), new BigInteger(p), new BigInteger(q), new BigInteger(g));
PrivateKey prvKey = keyFactory.generatePrivate(dsaPrivKeySpec);
signature.initSign(prvKey);
}
public void setPubKey(byte[] y, byte[] p, byte[] q, byte[] g) throws Exception {
DSAPublicKeySpec dsaPubKeySpec =
new DSAPublicKeySpec(
new BigInteger(y), new BigInteger(p), new BigInteger(q), new BigInteger(g));
PublicKey pubKey = keyFactory.generatePublic(dsaPubKeySpec);
signature.initVerify(pubKey);
}
public boolean verify(byte[] sig) throws Exception {
int i = 0;
int j = 0;
byte[] tmp;
if (sig[0] == 0 && sig[1] == 0 && sig[2] == 0) {
j =
((sig[i++] << 24) & 0xff000000)
| ((sig[i++] << 16) & 0x00ff0000)
| ((sig[i++] << 8) & 0x0000ff00)
| ((sig[i++]) & 0x000000ff);
i += j;
j =
((sig[i++] << 24) & 0xff000000)
| ((sig[i++] << 16) & 0x00ff0000)
| ((sig[i++] << 8) & 0x0000ff00)
| ((sig[i++]) & 0x000000ff);
tmp = new byte[j];
System.arraycopy(sig, i, tmp, 0, j);
sig = tmp;
}
// ASN.1
int frst = ((sig[0] & 0x80) != 0 ? 1 : 0);
int scnd = ((sig[20] & 0x80) != 0 ? 1 : 0);
// System.err.println("frst: "+frst+", scnd: "+scnd);
int length = sig.length + 6 + frst + scnd;
tmp = new byte[length];
tmp[0] = (byte) 0x30;
tmp[1] = (byte) 0x2c;
tmp[1] += frst;
tmp[1] += scnd;
tmp[2] = (byte) 0x02;
tmp[3] = (byte) 0x14;
tmp[3] += frst;
System.arraycopy(sig, 0, tmp, 4 + frst, 20);
tmp[4 + tmp[3]] = (byte) 0x02;
tmp[5 + tmp[3]] = (byte) 0x14;
tmp[5 + tmp[3]] += scnd;
System.arraycopy(sig, 20, tmp, 6 + tmp[3] + scnd, 20);
sig = tmp;
/*
tmp=new byte[sig.length+6];
tmp[0]=(byte)0x30; tmp[1]=(byte)0x2c;
tmp[2]=(byte)0x02; tmp[3]=(byte)0x14;
System.arraycopy(sig, 0, tmp, 4, 20);
tmp[24]=(byte)0x02; tmp[25]=(byte)0x14;
System.arraycopy(sig, 20, tmp, 26, 20); sig=tmp;
*/
return signature.verify(sig);
}
public byte[] sign() throws Exception {
byte[] sig = signature.sign();
/*
System.err.print("sign["+sig.length+"] ");
for(int i=0; i<sig.length;i++){
System.err.print(Integer.toHexString(sig[i]&0xff)+":");
}
System.err.println("");
*/
// sig is in ASN.1
// SEQUENCE::={ r INTEGER, s INTEGER }
int len = 0;
int index = 3;
len = sig[index++] & 0xff;
// System.err.println("! len="+len);
byte[] r = new byte[len];
System.arraycopy(sig, index, r, 0, r.length);
index = index + len + 1;
len = sig[index++] & 0xff;
// System.err.println("!! len="+len);
byte[] s = new byte[len];
System.arraycopy(sig, index, s, 0, s.length);
byte[] result = new byte[40];
// result must be 40 bytes, but length of r and s may not be 20 bytes
System.arraycopy(
r,
(r.length > 20) ? 1 : 0,
result,
(r.length > 20) ? 0 : 20 - r.length,
(r.length > 20) ? 20 : r.length);
System.arraycopy(
s,
(s.length > 20) ? 1 : 0,
result,
(s.length > 20) ? 20 : 40 - s.length,
(s.length > 20) ? 20 : s.length);
// System.arraycopy(sig, (sig[3]==20?4:5), result, 0, 20);
// System.arraycopy(sig, sig.length-20, result, 20, 20);
return result;
}
public boolean verify(byte[] sig) throws Exception {
int i = 0;
int j = 0;
byte[] tmp;
if (sig[0] == 0 && sig[1] == 0 && sig[2] == 0) {
j =
((sig[i++] << 24) & 0xff000000)
| ((sig[i++] << 16) & 0x00ff0000)
| ((sig[i++] << 8) & 0x0000ff00)
| ((sig[i++]) & 0x000000ff);
i += j;
j =
((sig[i++] << 24) & 0xff000000)
| ((sig[i++] << 16) & 0x00ff0000)
| ((sig[i++] << 8) & 0x0000ff00)
| ((sig[i++]) & 0x000000ff);
tmp = new byte[j];
System.arraycopy(sig, i, tmp, 0, j);
sig = tmp;
}
// System.err.println("j="+j+" "+Integer.toHexString(sig[0]&0xff));
return signature.verify(sig);
}
public void update(byte[] foo) throws Exception {
signature.update(foo);
}
public byte[] sign() throws Exception {
byte[] sig = signature.sign();
return sig;
}
public void setPrvKey(byte[] d, byte[] n) throws Exception {
RSAPrivateKeySpec rsaPrivKeySpec = new RSAPrivateKeySpec(new BigInteger(n), new BigInteger(d));
PrivateKey prvKey = keyFactory.generatePrivate(rsaPrivKeySpec);
signature.initSign(prvKey);
}
public void setPubKey(byte[] e, byte[] n) throws Exception {
RSAPublicKeySpec rsaPubKeySpec = new RSAPublicKeySpec(new BigInteger(n), new BigInteger(e));
PublicKey pubKey = keyFactory.generatePublic(rsaPubKeySpec);
signature.initVerify(pubKey);
}
public void init() throws Exception {
signature = java.security.Signature.getInstance("SHA1withRSA");
keyFactory = KeyFactory.getInstance("RSA");
}
