src/java.base/share/classes/sun/security/provider/DRBG.java - platform/libcore - Git at Google

 /*
  * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.  Oracle designates this
  * particular file as subject to the "Classpath" exception as provided
  * by Oracle in the LICENSE file that accompanied this code.
  *
  * This code 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 General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  */

 package sun.security.provider;

 import java.io.IOException;
 import java.security.AccessController;
 import java.security.DrbgParameters;
 import java.security.PrivilegedAction;
 import java.security.SecureRandomParameters;
 import java.security.SecureRandomSpi;
 import java.security.Security;
 import java.util.Locale;
 import static java.security.DrbgParameters.Capability.*;

 /**
  * Implement the "SecureRandom.DRBG" algorithm.
  *
  * About the default "securerandom.drbg.config" value:
  *
  * The default value in java.security is set to "". This is because
  * the default values of different aspects are dependent (For example,
  * strength depends on algorithm) and if we write a full string there
  * it will be difficult to modify one and keep all others legal.
  *
  * When changing default values, touch all places including:
  *
  * 1. comments of the security property in java.security
  * 2. Default mech, cap, usedf set in this class
  * 3. Default algorithm set in final implementation of each mech
  * 4. Default strength set in AbstractDrbg, but the effective
  *    value can be smaller if an algorithm does not support it.
  *
  * The default value is also mentioned in the @implNote part of
  * {@link DrbgParameters} class.
  */
 public final class DRBG extends SecureRandomSpi {

     private static final String PROP_NAME = "securerandom.drbg.config";

     private static final long serialVersionUID = 9L;

     private transient AbstractDrbg impl;

     /**
      * @serial
      */
     private final MoreDrbgParameters mdp;

     public DRBG(SecureRandomParameters params) {

         // All parameters at unset status (null or -1).

         // Configurable with the "securerandom.drbg.config" security property
         String mech = null;
         Boolean usedf = null;
         String algorithm = null;

         // Default instantiate parameters also configurable with
         // "securerandom.drbg.config", and can be changed with params
         // in getInstance("drbg", params)
         int strength = -1;
         DrbgParameters.Capability cap = null;
         byte[] ps = null;

         // Not configurable with public interfaces, but is a part of
         // MoreDrbgParameters
         EntropySource es = null;
         byte[] nonce = null;

         // Can be configured with a security property

         String config = AccessController.doPrivileged((PrivilegedAction<String>)
                 () -> Security.getProperty(PROP_NAME));

         if (config != null && !config.isEmpty()) {
             for (String part : config.split(",")) {
                 part = part.trim();
                 switch (part.toLowerCase(Locale.ROOT)) {
                     case "":
                         throw new IllegalArgumentException(
                                 "aspect in " + PROP_NAME + " cannot be empty");
                     case "pr_and_reseed":
                         checkTwice(cap != null, "capability");
                         cap = PR_AND_RESEED;
                         break;
                     case "reseed_only":
                         checkTwice(cap != null, "capability");
                         cap = RESEED_ONLY;
                         break;
                     case "none":
                         checkTwice(cap != null, "capability");
                         cap = NONE;
                         break;
                     case "hash_drbg":
                     case "hmac_drbg":
                     case "ctr_drbg":
                         checkTwice(mech != null, "mechanism name");
                         mech = part;
                         break;
                     case "no_df":
                         checkTwice(usedf != null, "usedf flag");
                         usedf = false;
                         break;
                     case "use_df":
                         checkTwice(usedf != null, "usedf flag");
                         usedf = true;
                         break;
                     default:
                         // For all other parts of the property, it is
                         // either an algorithm name or a strength
                         try {
                             int tmp = Integer.parseInt(part);
                             if (tmp < 0) {
                                 throw new IllegalArgumentException(
                                         "strength in " + PROP_NAME +
                                                 " cannot be negative: " + part);
                             }
                             checkTwice(strength >= 0, "strength");
                             strength = tmp;
                         } catch (NumberFormatException e) {
                             checkTwice(algorithm != null, "algorithm name");
                             algorithm = part;
                         }
                 }
             }
         }

         // Can be updated by params

         if (params != null) {
             // MoreDrbgParameters is used for testing.
             if (params instanceof MoreDrbgParameters) {
                 MoreDrbgParameters m = (MoreDrbgParameters) params;
                 params = DrbgParameters.instantiation(m.strength,
                         m.capability, m.personalizationString);

                 // No need to check null for es and nonce, they are still null
                 es = m.es;
                 nonce = m.nonce;

                 if (m.mech != null) {
                     mech = m.mech;
                 }
                 if (m.algorithm != null) {
                     algorithm = m.algorithm;
                 }
                 usedf = m.usedf;
             }
             if (params instanceof DrbgParameters.Instantiation) {
                 DrbgParameters.Instantiation dp =
                         (DrbgParameters.Instantiation) params;

                 // ps is still null by now
                 ps = dp.getPersonalizationString();

                 int tmp = dp.getStrength();
                 if (tmp != -1) {
                     strength = tmp;
                 }
                 cap = dp.getCapability();
             } else {
                 throw new IllegalArgumentException("Unsupported params: "
                         + params.getClass());
             }
         }

         // Hardcoded defaults.
         // Remember to sync with "securerandom.drbg.config" in java.security.

         if (cap == null) {
             cap = NONE;
         }
         if (mech == null) {
             mech = "Hash_DRBG";
         }
         if (usedf == null) {
             usedf = true;
         }

         mdp = new MoreDrbgParameters(
                 es, mech, algorithm, nonce, usedf,
                 DrbgParameters.instantiation(strength, cap, ps));

         createImpl();
     }

     private void createImpl() {
         switch (mdp.mech.toLowerCase(Locale.ROOT)) {
             case "hash_drbg":
                 impl = new HashDrbg(mdp);
                 break;
             case "hmac_drbg":
                 impl = new HmacDrbg(mdp);
                 break;
             case "ctr_drbg":
                 impl = new CtrDrbg(mdp);
                 break;
             default:
                 throw new IllegalArgumentException("Unsupported mech: " + mdp.mech);
         }
     }

     @Override
     protected void engineSetSeed(byte[] seed) {
         impl.engineSetSeed(seed);
     }

     @Override
     protected void engineNextBytes(byte[] bytes) {
         impl.engineNextBytes(bytes);
     }

     @Override
     protected byte[] engineGenerateSeed(int numBytes) {
         return impl.engineGenerateSeed(numBytes);
     }

     @Override
     protected void engineNextBytes(
             byte[] bytes, SecureRandomParameters params) {
         impl.engineNextBytes(bytes, params);
     }

     @Override
     protected void engineReseed(SecureRandomParameters params) {
         impl.engineReseed(params);
     }

     @Override
     protected SecureRandomParameters engineGetParameters() {
         return impl.engineGetParameters();
     }

     @Override
     public String toString() {
         return impl.toString();
     }

     /**
      * Ensures an aspect is not set more than once.
      *
      * @param flag true if set more than once
      * @param name the name of aspect shown in IAE
      * @throws IllegalArgumentException if it happens
      */
     private static void checkTwice(boolean flag, String name) {
         if (flag) {
             throw new IllegalArgumentException(name
                     + " cannot be provided more than once in " + PROP_NAME);
         }
     }

     private void readObject(java.io.ObjectInputStream s)
             throws IOException, ClassNotFoundException {
         s.defaultReadObject();
         if (mdp.mech == null) {
             throw new IllegalArgumentException("Input data is corrupted");
         }
         createImpl();
     }
 }
	/*
	* Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code 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 General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/

	package sun.security.provider;

	import java.io.IOException;
	import java.security.AccessController;
	import java.security.DrbgParameters;
	import java.security.PrivilegedAction;
	import java.security.SecureRandomParameters;
	import java.security.SecureRandomSpi;
	import java.security.Security;
	import java.util.Locale;
	import static java.security.DrbgParameters.Capability.*;

	/**
	* Implement the "SecureRandom.DRBG" algorithm.
	*
	* About the default "securerandom.drbg.config" value:
	*
	* The default value in java.security is set to "". This is because
	* the default values of different aspects are dependent (For example,
	* strength depends on algorithm) and if we write a full string there
	* it will be difficult to modify one and keep all others legal.
	*
	* When changing default values, touch all places including:
	*
	* 1. comments of the security property in java.security
	* 2. Default mech, cap, usedf set in this class
	* 3. Default algorithm set in final implementation of each mech
	* 4. Default strength set in AbstractDrbg, but the effective
	* value can be smaller if an algorithm does not support it.
	*
	* The default value is also mentioned in the @implNote part of
	* {@link DrbgParameters} class.
	*/
	public final class DRBG extends SecureRandomSpi {

	private static final String PROP_NAME = "securerandom.drbg.config";

	private static final long serialVersionUID = 9L;

	private transient AbstractDrbg impl;

	/**
	* @serial
	*/
	private final MoreDrbgParameters mdp;

	public DRBG(SecureRandomParameters params) {

	// All parameters at unset status (null or -1).

	// Configurable with the "securerandom.drbg.config" security property
	String mech = null;
	Boolean usedf = null;
	String algorithm = null;

	// Default instantiate parameters also configurable with
	// "securerandom.drbg.config", and can be changed with params
	// in getInstance("drbg", params)
	int strength = -1;
	DrbgParameters.Capability cap = null;
	byte[] ps = null;

	// Not configurable with public interfaces, but is a part of
	// MoreDrbgParameters
	EntropySource es = null;
	byte[] nonce = null;

	// Can be configured with a security property

	String config = AccessController.doPrivileged((PrivilegedAction<String>)
	() -> Security.getProperty(PROP_NAME));

	if (config != null && !config.isEmpty()) {
	for (String part : config.split(",")) {
	part = part.trim();
	switch (part.toLowerCase(Locale.ROOT)) {
	case "":
	throw new IllegalArgumentException(
	"aspect in " + PROP_NAME + " cannot be empty");
	case "pr_and_reseed":
	checkTwice(cap != null, "capability");
	cap = PR_AND_RESEED;
	break;
	case "reseed_only":
	checkTwice(cap != null, "capability");
	cap = RESEED_ONLY;
	break;
	case "none":
	checkTwice(cap != null, "capability");
	cap = NONE;
	break;
	case "hash_drbg":
	case "hmac_drbg":
	case "ctr_drbg":
	checkTwice(mech != null, "mechanism name");
	mech = part;
	break;
	case "no_df":
	checkTwice(usedf != null, "usedf flag");
	usedf = false;
	break;
	case "use_df":
	checkTwice(usedf != null, "usedf flag");
	usedf = true;
	break;
	default:
	// For all other parts of the property, it is
	// either an algorithm name or a strength
	try {
	int tmp = Integer.parseInt(part);
	if (tmp < 0) {
	throw new IllegalArgumentException(
	"strength in " + PROP_NAME +
	" cannot be negative: " + part);
	}
	checkTwice(strength >= 0, "strength");
	strength = tmp;
	} catch (NumberFormatException e) {
	checkTwice(algorithm != null, "algorithm name");
	algorithm = part;
	}
	}
	}
	}

	// Can be updated by params

	if (params != null) {
	// MoreDrbgParameters is used for testing.
	if (params instanceof MoreDrbgParameters) {
	MoreDrbgParameters m = (MoreDrbgParameters) params;
	params = DrbgParameters.instantiation(m.strength,
	m.capability, m.personalizationString);

	// No need to check null for es and nonce, they are still null
	es = m.es;
	nonce = m.nonce;

	if (m.mech != null) {
	mech = m.mech;
	}
	if (m.algorithm != null) {
	algorithm = m.algorithm;
	}
	usedf = m.usedf;
	}
	if (params instanceof DrbgParameters.Instantiation) {
	DrbgParameters.Instantiation dp =
	(DrbgParameters.Instantiation) params;

	// ps is still null by now
	ps = dp.getPersonalizationString();

	int tmp = dp.getStrength();
	if (tmp != -1) {
	strength = tmp;
	}
	cap = dp.getCapability();
	} else {
	throw new IllegalArgumentException("Unsupported params: "
	+ params.getClass());
	}
	}

	// Hardcoded defaults.
	// Remember to sync with "securerandom.drbg.config" in java.security.

	if (cap == null) {
	cap = NONE;
	}
	if (mech == null) {
	mech = "Hash_DRBG";
	}
	if (usedf == null) {
	usedf = true;
	}

	mdp = new MoreDrbgParameters(
	es, mech, algorithm, nonce, usedf,
	DrbgParameters.instantiation(strength, cap, ps));

	createImpl();
	}

	private void createImpl() {
	switch (mdp.mech.toLowerCase(Locale.ROOT)) {
	case "hash_drbg":
	impl = new HashDrbg(mdp);
	break;
	case "hmac_drbg":
	impl = new HmacDrbg(mdp);
	break;
	case "ctr_drbg":
	impl = new CtrDrbg(mdp);
	break;
	default:
	throw new IllegalArgumentException("Unsupported mech: " + mdp.mech);
	}
	}

	@Override
	protected void engineSetSeed(byte[] seed) {
	impl.engineSetSeed(seed);
	}

	@Override
	protected void engineNextBytes(byte[] bytes) {
	impl.engineNextBytes(bytes);
	}

	@Override
	protected byte[] engineGenerateSeed(int numBytes) {
	return impl.engineGenerateSeed(numBytes);
	}

	@Override
	protected void engineNextBytes(
	byte[] bytes, SecureRandomParameters params) {
	impl.engineNextBytes(bytes, params);
	}

	@Override
	protected void engineReseed(SecureRandomParameters params) {
	impl.engineReseed(params);
	}

	@Override
	protected SecureRandomParameters engineGetParameters() {
	return impl.engineGetParameters();
	}

	@Override
	public String toString() {
	return impl.toString();
	}

	/**
	* Ensures an aspect is not set more than once.
	*
	* @param flag true if set more than once
	* @param name the name of aspect shown in IAE
	* @throws IllegalArgumentException if it happens
	*/
	private static void checkTwice(boolean flag, String name) {
	if (flag) {
	throw new IllegalArgumentException(name
	+ " cannot be provided more than once in " + PROP_NAME);
	}
	}

	private void readObject(java.io.ObjectInputStream s)
	throws IOException, ClassNotFoundException {
	s.defaultReadObject();
	if (mdp.mech == null) {
	throw new IllegalArgumentException("Input data is corrupted");
	}
	createImpl();
	}
	}