According to API, KeyFactory.generatePrivate should accept the RSAMultiPrimePrivateCrtKeySpec since RSAMultiPrimePrivateCrtKeySpec implements Keyspec. The following program demonstrates this.


import java.security.spec.*;
import java.security.interfaces.*;
import java.math.*;
import java.security.*;

public class test{

public static void main(String[] argv) throws Exception{

BigInteger modulus=new BigInteger("385");
BigInteger publicExponent=new BigInteger("7");
         BigInteger privateExponent=new BigInteger("43");
         BigInteger primeP=new BigInteger("5");
         BigInteger primeQ=new BigInteger("7");
         BigInteger primeExponentP=new BigInteger("3");
         BigInteger primeExponentQ=new BigInteger("1");
         BigInteger crtCoefficient=new BigInteger("3");
        
         //r3=11, d3=3, t3=6
         BigInteger r3=new BigInteger("11");
         BigInteger d3=new BigInteger("3");
         BigInteger t3=new BigInteger("6");
        
         RSAOtherPrimeInfo otherInfo=new RSAOtherPrimeInfo(r3, d3, t3);
         RSAOtherPrimeInfo[] otherPrimeInfo=new RSAOtherPrimeInfo[1];
         otherPrimeInfo[0]=otherInfo;

RSAMultiPrimePrivateCrtKeySpec crtKeySpec =new RSAMultiPrimePrivateCrtKeySpec(modulus,
publicExponent, privateExponent,primeP,primeQ,primeExponentP,primeExponentQ,
crtCoefficient,otherPrimeInfo);

Key priv = null;
KeyFactory kf = KeyFactory.getInstance("RSA");
System.out.println("The Provider is "+kf.getProvider());
priv = kf.generatePrivate( crtKeySpec);

}
}

lwang:/home/lw129730/CCC/4478091( 114 )%java test
The Provider is SunJSSE version 1.4
Exception in thread "main" java.security.spec.InvalidKeySpecException: Unknown key spec.
        at com.sun.net.ssl.internal.ssl.JS_KeyFactory.engineGeneratePrivate(DashoA6275)
        at java.security.KeyFactory.generatePrivate(KeyFactory.java:240)
        at test.main(test.java:38)