Gonna try jboss srp implementation, because if I implement myself one we

will have to audit it.

1 files changed, 289 insertions, 0 deletions

diff --git a/src/org/jboss/security/srp/SRPClientSession.java b/src/org/jboss/security/srp/SRPClientSession.java
new file mode 100644
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--- /dev/null
+++ b/src/org/jboss/security/srp/SRPClientSession.java
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+/*
+ * JBoss, Home of Professional Open Source.
+ * Copyright 2008, Red Hat Middleware LLC, and individual contributors
+ * as indicated by the @author tags. See the copyright.txt file in the
+ * distribution for a full listing of individual contributors.
+ *
+ * This is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as
+ * published by the Free Software Foundation; either version 2.1 of
+ * the License, or (at your option) any later version.
+ *
+ * This software is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this software; if not, write to the Free
+ * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
+ * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
+ */
+package org.jboss.security.srp;
+
+import java.math.BigInteger;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.util.Arrays;
+
+import org.jboss.crypto.CryptoUtil;
+import org.jboss.logging.Logger; 
+
+/** The client side logic to the SRP protocol. The class is intended to be used
+ * with a SRPServerSession object via the SRPServerInterface. The SRP algorithm
+ * using these classes consists of:
+ *
+ * 1. Get server, SRPServerInterface server = (SRPServerInterface) Naming.lookup(...);
+ * 2. Get SRP parameters, SRPParameters params = server.getSRPParameters(username);
+ * 3. Create a client session, SRPClientSession client = new SRPClientSession(username,
+ * password, params);
+ * 4. Exchange public keys, byte[] A = client.exponential();
+ * byte[] B = server.init(username, A);
+ * 5. Exchange challenges, byte[] M1 = client.response(B);
+ * byte[] M2 = server.verify(username, M1);
+ * 6. Verify the server response, if( client.verify(M2) == false )
+ * throw new SecurityException("Failed to validate server reply");
+ * 7. Validation complete
+ *
+ * Note that these steps are stateful. They must be performed in order and a
+ * step cannot be repeated to update the session state.
+ *
+ * This product uses the 'Secure Remote Password' cryptographic
+ * authentication system developed by Tom Wu (tjw@CS.Stanford.EDU).
+ *
+ * @author Scott.Stark@jboss.org
+ * @version $Revision: 81038 $
+ */
+public class SRPClientSession
+{
+   private static Logger log = Logger.getLogger(SRPClientSession.class);
+   private SRPParameters params;
+   private BigInteger N;
+   private BigInteger g;
+   private BigInteger x;
+   private BigInteger v;
+   private byte[] s;
+   private BigInteger a;
+   private BigInteger A;
+   private byte[] K;
+   /** The M1 = H(H(N) xor H(g) | H(U) | s | A | B | K) hash */
+   private MessageDigest clientHash;
+   /** The M2 = H(A | M | K) hash */
+   private MessageDigest serverHash;
+   
+   private static int A_LEN = 64;
+   
+   /** Creates a new SRP server session object from the username, password
+    verifier,
+    @param username, the user ID
+    @param password, the user clear text password
+    @param params, the SRP parameters for the session
+    */
+   public SRPClientSession(String username, char[] password, SRPParameters params)
+   {
+      this(username, password, params, null);
+   }
+
+   /** Creates a new SRP server session object from the username, password
+    verifier,
+    @param username, the user ID
+    @param password, the user clear text password
+    @param params, the SRP parameters for the session
+    @param abytes, the random exponent used in the A public key. This must be
+      8 bytes in length.
+    */
+   public SRPClientSession(String username, char[] password, SRPParameters params,
+      byte[] abytes)
+   {
+      try
+      {
+         // Initialize the secure random number and message digests
+         CryptoUtil.init();
+      }
+      catch(NoSuchAlgorithmException e)
+      {
+      }
+      this.params = params;
+      this.g = new BigInteger(1, params.g);
+      this.N = new BigInteger(1, params.N);
+      if( abytes != null )
+      {
+         if( 8*abytes.length != A_LEN )
+            throw new IllegalArgumentException("The abytes param must be "
+               +(A_LEN/8)+" in length, abytes.length="+abytes.length);
+         this.a = new BigInteger(abytes);
+      }
+
+      if( log.isTraceEnabled() )
+         log.trace("g: "+CryptoUtil.tob64(params.g));
+      // Calculate x = H(s | H(U | ':' | password))
+      byte[] xb = CryptoUtil.calculatePasswordHash(username, password, params.s);
+      if( log.isTraceEnabled() )
+         log.trace("x: "+CryptoUtil.tob64(xb));
+      this.x = new BigInteger(1, xb);
+      this.v = g.modPow(x, N);  // g^x % N
+      if( log.isTraceEnabled() )
+         log.trace("v: "+CryptoUtil.tob64(v.toByteArray()));
+      
+      serverHash = CryptoUtil.newDigest();
+      clientHash = CryptoUtil.newDigest();
+      // H(N)
+      byte[] hn = CryptoUtil.newDigest().digest(params.N);
+      if( log.isTraceEnabled() )
+         log.trace("H(N): "+CryptoUtil.tob64(hn));
+      // H(g)
+      byte[] hg = CryptoUtil.newDigest().digest(params.g);
+      if( log.isTraceEnabled() )
+         log.trace("H(g): "+CryptoUtil.tob64(hg));
+      // clientHash = H(N) xor H(g)
+      byte[] hxg = CryptoUtil.xor(hn, hg, 20);
+      if( log.isTraceEnabled() )
+         log.trace("H(N) xor H(g): "+CryptoUtil.tob64(hxg));
+      clientHash.update(hxg);
+      if( log.isTraceEnabled() )
+      {
+         MessageDigest tmp = CryptoUtil.copy(clientHash);
+         log.trace("H[H(N) xor H(g)]: "+CryptoUtil.tob64(tmp.digest()));
+      }
+      // clientHash = H(N) xor H(g) | H(U)
+      clientHash.update(CryptoUtil.newDigest().digest(username.getBytes()));
+      if( log.isTraceEnabled() )
+      {
+         MessageDigest tmp = CryptoUtil.copy(clientHash);
+         log.trace("H[H(N) xor H(g) | H(U)]: "+CryptoUtil.tob64(tmp.digest()));
+      }
+      // clientHash = H(N) xor H(g) | H(U) | s
+      clientHash.update(params.s);
+      if( log.isTraceEnabled() )
+      {
+         MessageDigest tmp = CryptoUtil.copy(clientHash);
+         log.trace("H[H(N) xor H(g) | H(U) | s]: "+CryptoUtil.tob64(tmp.digest()));
+      }
+      K = null;
+   }
+   
+   /**
+    * @returns The exponential residue (parameter A) to be sent to the server.
+    */
+   public byte[] exponential()
+   {
+      byte[] Abytes = null;
+      if(A == null)
+      {
+         /* If the random component of A has not been specified use a random
+         number */
+         if( a == null )
+         {
+            BigInteger one = BigInteger.ONE;
+            do
+            {
+               a = new BigInteger(A_LEN, CryptoUtil.getPRNG());
+            } while(a.compareTo(one) <= 0);
+         }
+         A = g.modPow(a, N);
+         Abytes = CryptoUtil.trim(A.toByteArray());
+         // clientHash = H(N) xor H(g) | H(U) | A
+         clientHash.update(Abytes);
+         if( log.isTraceEnabled() )
+         {
+            MessageDigest tmp = CryptoUtil.copy(clientHash);
+            log.trace("H[H(N) xor H(g) | H(U) | s | A]: "+CryptoUtil.tob64(tmp.digest()));
+         }
+         // serverHash = A
+         serverHash.update(Abytes);
+      }
+      return Abytes;
+   }
+   
+   /**
+    @returns M1 = H(H(N) xor H(g) | H(U) | s | A | B | K)
+    @exception NoSuchAlgorithmException thrown if the session key
+    MessageDigest algorithm cannot be found.
+    */
+   public byte[] response(byte[] Bbytes) throws NoSuchAlgorithmException
+   {
+      // clientHash = H(N) xor H(g) | H(U) | s | A | B
+      clientHash.update(Bbytes);
+      if( log.isTraceEnabled() )
+      {
+         MessageDigest tmp = CryptoUtil.copy(clientHash);
+         log.trace("H[H(N) xor H(g) | H(U) | s | A | B]: "+CryptoUtil.tob64(tmp.digest()));
+      }
+      // Calculate u as the first 32 bits of H(B)
+      byte[] hB = CryptoUtil.newDigest().digest(Bbytes);
+      byte[] ub =
+      {hB[0], hB[1], hB[2], hB[3]};
+      // Calculate S = (B - g^x) ^ (a + u * x) % N
+      BigInteger B = new BigInteger(1, Bbytes);
+      if( log.isTraceEnabled() )
+         log.trace("B: "+CryptoUtil.tob64(B.toByteArray()));
+      if( B.compareTo(v) < 0 )
+         B = B.add(N);
+      if( log.isTraceEnabled() )
+         log.trace("B': "+CryptoUtil.tob64(B.toByteArray()));
+      if( log.isTraceEnabled() )
+         log.trace("v: "+CryptoUtil.tob64(v.toByteArray()));
+      BigInteger u = new BigInteger(1, ub);
+      if( log.isTraceEnabled() )
+         log.trace("u: "+CryptoUtil.tob64(u.toByteArray()));
+      BigInteger B_v = B.subtract(v);
+      if( log.isTraceEnabled() )
+         log.trace("B - v: "+CryptoUtil.tob64(B_v.toByteArray()));
+      BigInteger a_ux = a.add(u.multiply(x));
+      if( log.isTraceEnabled() )
+         log.trace("a + u * x: "+CryptoUtil.tob64(a_ux.toByteArray()));
+      BigInteger S = B_v.modPow(a_ux, N);
+      if( log.isTraceEnabled() )
+         log.trace("S: "+CryptoUtil.tob64(S.toByteArray()));
+      // K = SessionHash(S)
+      MessageDigest sessionDigest = MessageDigest.getInstance(params.hashAlgorithm);
+      K = sessionDigest.digest(S.toByteArray());
+      if( log.isTraceEnabled() )
+         log.trace("K: "+CryptoUtil.tob64(K));
+      // clientHash = H(N) xor H(g) | H(U) | A | B | K
+      clientHash.update(K);
+      byte[] M1 = clientHash.digest();
+      if( log.isTraceEnabled() )
+         log.trace("M1: H[H(N) xor H(g) | H(U) | s | A | B | K]: "+CryptoUtil.tob64(M1));
+      serverHash.update(M1);
+      serverHash.update(K);
+      if( log.isTraceEnabled() )
+      {
+         MessageDigest tmp = CryptoUtil.copy(serverHash);
+         log.trace("H[A | M1 | K]: "+CryptoUtil.tob64(tmp.digest()));
+      }
+      return M1;
+   }
+   /**
+    * @param M2 The server's response to the client's challenge
+    * @returns True if and only if the server's response was correct.
+    */
+   public boolean verify(byte[] M2)
+   {
+      // M2 = H(A | M1 | K)
+      byte[] myM2 = serverHash.digest();
+      boolean valid = Arrays.equals(M2, myM2);
+      if( log.isTraceEnabled() )
+      {
+         log.trace("verify serverM2: "+CryptoUtil.tob64(M2));
+         log.trace("verify M2: "+CryptoUtil.tob64(myM2));
+      }
+      return valid;
+   }
+   
+   /** Returns the negotiated session K, K = SHA_Interleave(S)
+    @return the private session K byte[]
+    @throws SecurityException - if the current thread does not have an
+    getSessionKey SRPPermission.
+    */
+   public byte[] getSessionKey() throws SecurityException
+   {
+      SecurityManager sm = System.getSecurityManager();
+      if( sm != null )
+      {
+         SRPPermission p = new SRPPermission("getSessionKey");
+         sm.checkPermission(p);
+      }
+      return K;
+   }
+}