r27197 - trunk/freenet/src/freenet/crypt
[email protected] Wed, 22 Apr 2009 07:28:30 +0000
| Newsgroups | gmane.network.freenet.cvs |
|---|---|
| Message-ID | <[email protected]> |
Author: j16sdiz
Date: 2009-04-22 07:28:30 +0000 (Wed, 22 Apr 2009)
New Revision: 27197
Removed:
trunk/freenet/src/freenet/crypt/DSAGroupGenerator.java
Log:
Unused class: DSAGroupGenerator
Deleted: trunk/freenet/src/freenet/crypt/DSAGroupGenerator.java
===================================================================
--- trunk/freenet/src/freenet/crypt/DSAGroupGenerator.java 2009-04-22 07:28:09 UTC (rev 27196)
+++ trunk/freenet/src/freenet/crypt/DSAGroupGenerator.java 2009-04-22 07:28:30 UTC (rev 27197)
@@ -1,202 +0,0 @@
-/* This code is part of Freenet. It is distributed under the GNU General
- * Public License, version 2 (or at your option any later version). See
- * http://www.gnu.org/ for further details of the GPL. */
-package freenet.crypt;
-
-import java.math.BigInteger;
-import java.security.MessageDigest;
-import java.security.NoSuchAlgorithmException;
-
-import net.i2p.util.NativeBigInteger;
-
-import freenet.support.HexUtil;
-
-/**
- * DSA Group Generator.
- * Adapted from FIPS 186-2.
- * Can generate valid groups of any keysize and any hash length.
- */
-public class DSAGroupGenerator {
-
- static BigInteger smallPrimes[] = new BigInteger[] { BigInteger.valueOf(3),
- BigInteger.valueOf(5), BigInteger.valueOf(7),
- BigInteger.valueOf(11), BigInteger.valueOf(13),
- BigInteger.valueOf(17), BigInteger.valueOf(19),
- BigInteger.valueOf(23), BigInteger.valueOf(29)};
-
- public static void main(String[] args) throws NoSuchAlgorithmException {
- Yarrow r = new Yarrow();
- int keyLength = Integer.parseInt(args[0]);
- int hashLength = Integer.parseInt(args[1]);
- System.out.println("Key length: "+keyLength);
- System.out.println("Hash length: "+hashLength);
- if(hashLength > keyLength)
- throw new IllegalArgumentException("hashLength must not be greater than keyLength");
- MessageDigest md;
- if(hashLength == 256) {
- md = SHA256.getMessageDigest();
- } else if(hashLength == 160) {
- md = MessageDigest.getInstance("SHA-160");
- } else {
- throw new IllegalArgumentException("Invalid hash length "+hashLength);
- }
- if(keyLength % 64 != 0)
- throw new IllegalArgumentException("Key length must be divisible by 64");
- if(keyLength % hashLength != 0)
- throw new IllegalArgumentException("Key length must be divisible by hash length (short cut taken here)");
- while(!generate(r, keyLength, hashLength, md));
- }
-
- private static boolean generate(RandomSource r, int keyLength, int hashLength, MessageDigest md) {
-
- int n = keyLength / hashLength;
-
- // 1: SEED = arbitrary sequence of at least hashLength bits
- // g = length of SEED in bits
- int g = hashLength * 2;
- byte[] seed = new byte[g/8];
- r.nextBytes(seed);
-
- // 2: U = SHA-256(SEED) XOR SHA-256(SEED+1 mod 2^g)
- byte[] seedPlus1 = increment(seed);
- byte[] seedHash = md.digest(seed);
- byte[] seedPlus1Hash = md.digest(seedPlus1);
- byte[] U = new byte[hashLength/8];
- for(int i=0;i<U.length;i++)
- U[i] = (byte) (seedHash[i] ^ seedPlus1Hash[i]);
-
- // 3: Set LSB and MSB on U to 1, q = U
- byte[] qBuf = new byte[hashLength/8];
- System.arraycopy(U, 0, qBuf, 0, hashLength/8);
- qBuf[0] = (byte) (qBuf[0] | 128);
- qBuf[qBuf.length-1] = (byte) (qBuf[qBuf.length-1] | 1);
- BigInteger q = new BigInteger(1, qBuf);
-
- // 4: Check that q is prime, and 2q+1 is prime
- // 5: If not, restart from step 1
-
- System.out.println("Maybe got prime: "+q.toString(16)+ " ("+q.bitLength()+ ')');
-
- if(!isPrime(q))
- return false;
-
- System.out.println("Got prime q");
-
- BigInteger sophieGermainCheck = q.add(q).add(BigInteger.ONE);
- if(!isPrime(sophieGermainCheck))
- return false;
-
- System.out.println("Got SG-prime q");
-
- // 6: Let counter = 0 and offset = 2
-
- int counter = 0;
- int offset = 2;
-
- byte[] curSeed = seedPlus1;
-
- while(true) {
-
- // 7: For k = 0...n let V_k = SHA-256((SEED+offset+k) mod 2^g)
-
- byte[][] V = new byte[n][];
-
- for(int i=0;i<n;i++) {
- curSeed = increment(curSeed);
- V[i] = md.digest(curSeed);
- }
-
- // 8: Pack all the V's into W bit-wise, set the top bit so is between 2^(L-1) and 2^L
- byte[] Wbuf = new byte[keyLength/8];
- for(int i=0;i<keyLength;i+=hashLength) {
- System.arraycopy(V[i/hashLength], 0, Wbuf, i/8, hashLength/8);
- }
- Wbuf[0] = (byte) (Wbuf[0] | 128);
-
- BigInteger X = new NativeBigInteger(1, Wbuf);
-
- // 9: Let c = X mod 2q. Set p = X - ( c - 1 ). Therefore p mod 2q = 1.
-
- BigInteger c = X.mod(q.add(q));
- BigInteger p = X.subtract(c.subtract(BigInteger.ONE));
-
- if(p.bitLength() >= keyLength-1) {
- if(isPrime(p)) {
- finish(r, hashLength, new NativeBigInteger(p), new NativeBigInteger(q), seed, counter);
- return true;
- }
- }
-
- counter++;
- offset += n;
- if(counter >= 4096) return false;
- }
- }
-
- private static void finish(RandomSource r, int hashLength, NativeBigInteger p, NativeBigInteger q, byte[] seed, int counter) {
- System.out.println("SEED: "+HexUtil.bytesToHex(seed));
- System.out.println("COUNTER: "+counter);
- System.out.println("p: "+p.toString(16)+" ("+p.bitLength()+ ')');
- System.out.println("q: "+q.toString(16)+" ("+q.bitLength()+ ')');
- // Now generate g (algorithm from appendix 4 of FIPS 186-2)
- NativeBigInteger g;
- do {
- BigInteger e = p.subtract(BigInteger.ONE).divide(q);
- NativeBigInteger h;
- do {
- h = new NativeBigInteger(hashLength, r);
- } while(h.compareTo(p.subtract(BigInteger.ONE)) >= 0);
- g = (NativeBigInteger) h.modPow(e, p);
- } while (g.equals(BigInteger.ONE));
- DSAGroup group = new DSAGroup(p, q, g);
- System.out.println("g: "+g.toHexString()+" ("+g.bitLength()+ ')');
- System.out.println("Group: "+group.verboseToString());
- long totalSigTime = 0;
- long totalVerifyTime = 0;
- for(int i=0;i<10000;i++) {
- byte[] testHash = new byte[hashLength/8];
- r.nextBytes(testHash);
- NativeBigInteger m = new NativeBigInteger(1, testHash);
- DSAPrivateKey privKey = new DSAPrivateKey(group, r);
- DSAPublicKey pubKey = new DSAPublicKey(group, privKey);
- long now = System.currentTimeMillis();
- DSASignature sig = DSA.sign(group, privKey, m, r);
- long middle = System.currentTimeMillis();
- boolean success = DSA.verify(pubKey, sig, m, false);
- long end = System.currentTimeMillis();
- if(success) {
- totalSigTime += (middle - now);
- totalVerifyTime += (end - middle);
- } else {
- System.out.println("SIGNATURE VERIFICATION FAILED!!!");
- System.exit(1);
- }
- }
- System.out.println("Successfully signed and verified 10,000 times, average sig time "+totalSigTime / 10000.0 +", average verify time "+totalVerifyTime/10000.0);
- }
-
- private static byte[] increment(byte[] seed) {
- byte[] obuf = new byte[seed.length];
- System.arraycopy(seed, 0, obuf, 0, seed.length);
- int pos = seed.length-1;
- while(pos >= 0) {
- byte b = (byte) (obuf[pos] + 1);
- obuf[pos] = b;
- if(b != 0) return obuf;
- pos--;
- }
- return obuf;
- }
-
- public static boolean isPrime(BigInteger b) {
- if(BigInteger.ONE.compareTo(b) > -1)
- throw new IllegalArgumentException("Can't be a prime number!");
- for(int i = 0; i < smallPrimes.length; i++) {
- if(b.mod(smallPrimes[i]).equals(BigInteger.ZERO))
- return false;
- }
- // FIPS 186-2 recommends 2^100:1 confidence
- return b.isProbablePrime(200);
- }
-
-}