How to find modulus(n) and public key exponent(e)Sor

Question

I did the following code:
import java.security.*;
class keypair
public static void main(String args[])
try {
        KeyPairGenerator keyGen = KeyPairGenerator.getInstance("RSA");
        keyGen.initialize(1024);
        KeyPair keypair = keyGen.genKeyPair();
        PrivateKey privateKey = keypair.getPrivate();
        PublicKey publicKey = keypair.getPublic();
        System.out.println(publicKey);
catch (java.security.NoSuchAlgorithmException e) {
}It produced the following output:
E:\java>java keypair
Sun RSA public key, 1024 bits
modulus: 104598424699919432698042124865237006532583108525971624656815039032375
*68185931249899603942873174007833898125332457427834491991685017307342129730049040*
*85039266578793603162921901877391682504673766949037045217194339504369288262569809*
*64618725280325930282787918761626276736975012559809247463223114702205350103039131*
public exponent: 65537
How to parse modulus(n) and public exponent(e) from this output?
Similarly when i print private key, it produces the following output:
E:\java>java keypair
Sun RSA private CRT key, 1024 bits
modulus:          124578817060208658480856678950235831207402457067036419284514
*60119309486714863949162442643168408523979997168613499493638925829235693238993015*
*36861462235708805467117179894466762970147852286192228334073408407380525883650965*
*26200137024900438305422984852314541271126647102071346646999343089444655087519613*
*147762713*
public exponent:  65537
private exponent: 938527844532658207604152892230342202756165450473898580852699
*91069268853864683730106242370135012901790500054313488639918623825755509450966957*
*25996151023641565209086629652161258725723528561744214714448113895688480371394495*
*69970533766968335232379493089928062691491508442909468663624841001227918721233934*
*90451285*
prime p:          128112715803862066344339615342766575233634768887073748611821
*70613165835421234259251719401979554816266892921739504796026180704477109334458578*
*924582228715587*
prime q:          972415706579323990162180646771186062588725555167352041581263
*11833654947284058644791019214876691698044764118648637510099163830088827138987158*
*06445271350899*
prime exponent p: 102053075991522697645186596252261651077210381075096084960080
*01572103324900452503753532555651687424478224695551102238145517644352533224205327*
*850477437666141*
prime exponent q: 668659136319899226645386130685620335239039277715133737489656
*56694442226518700929665796129185316864860876985624927131126216000167126890435269*
*81971346772483*
crt coefficient:  337801534982286124613379128447816812903646302193598735486466
*78634104811105616496519276355880320340688935923186965279527763125244878069735173*
*60542121091569*
E:\java>
From this output how to parse n and d, where d is the secret exponent or decryption exponent? Thanks in advance. Apologies, for posting in this forum instead of cryptography forum.
Edited by: sowndar on Nov 28, 2009 3:12 AM

Answer 1

sowndar wrote:
From this output how to parse n and d, where d is the secret exponent or decryption exponent? Why do you think you need to parse anything? Why do you need the modulus and exponents?
P.S. Extract the public and private keys from the key pair, cast them to RSAPublicKey and RSAPrivateKey as appropriate then look at the methods of classes RSAPublicKey and RSAPrivateKey to see how to get modulus and exponents.