| /* |
| * Copyright 2016 The Android Open Source Project |
| * Copyright (c) 2012, 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.util; |
| |
| import java.security.Key; |
| import java.security.PrivilegedAction; |
| import java.security.AccessController; |
| import java.security.InvalidKeyException; |
| import java.security.interfaces.ECKey; |
| import java.security.interfaces.RSAKey; |
| import java.security.interfaces.DSAKey; |
| import java.security.interfaces.DSAParams; |
| import java.security.spec.ECParameterSpec; |
| import java.security.spec.KeySpec; |
| import javax.crypto.SecretKey; |
| import javax.crypto.interfaces.DHKey; |
| import javax.crypto.interfaces.DHPublicKey; |
| import javax.crypto.spec.DHParameterSpec; |
| import javax.crypto.spec.DHPublicKeySpec; |
| import java.math.BigInteger; |
| |
| /** |
| * A utility class to get key length, valiate keys, etc. |
| */ |
| public final class KeyUtil { |
| |
| /** |
| * Returns the key size of the given key object in bits. |
| * |
| * @param key the key object, cannot be null |
| * @return the key size of the given key object in bits, or -1 if the |
| * key size is not accessible |
| */ |
| public static final int getKeySize(Key key) { |
| int size = -1; |
| |
| if (key instanceof Length) { |
| try { |
| Length ruler = (Length)key; |
| size = ruler.length(); |
| } catch (UnsupportedOperationException usoe) { |
| // ignore the exception |
| } |
| |
| if (size >= 0) { |
| return size; |
| } |
| } |
| |
| // try to parse the length from key specification |
| if (key instanceof SecretKey) { |
| SecretKey sk = (SecretKey)key; |
| String format = sk.getFormat(); |
| if ("RAW".equals(format) && sk.getEncoded() != null) { |
| size = (sk.getEncoded().length * 8); |
| } // Otherwise, it may be a unextractable key of PKCS#11, or |
| // a key we are not able to handle. |
| } else if (key instanceof RSAKey) { |
| RSAKey pubk = (RSAKey)key; |
| size = pubk.getModulus().bitLength(); |
| } else if (key instanceof ECKey) { |
| ECKey pubk = (ECKey)key; |
| ECParameterSpec params = pubk.getParams(); |
| // According to RFC 3279 section 2.3.5, EC keys are allowed |
| // to inherit parameters in an X.509 certificate issuer's |
| // key parameters, so the parameters may be null. The parent |
| // key will be rejected if its parameters don't pass, so this |
| // is okay. |
| if (params != null) { |
| size = params.getOrder().bitLength(); |
| } |
| } else if (key instanceof DSAKey) { |
| DSAKey pubk = (DSAKey)key; |
| DSAParams params = pubk.getParams(); |
| // According to RFC 3279 section 2.3.2, DSA keys are allowed |
| // to inherit parameters in an X.509 certificate issuer's |
| // key parameters, so the parameters may be null. The parent |
| // key will be rejected if its parameters don't pass, so this |
| // is okay. |
| if (params != null) { |
| size = params.getP().bitLength(); |
| } |
| } else if (key instanceof DHKey) { |
| DHKey pubk = (DHKey)key; |
| size = pubk.getParams().getP().bitLength(); |
| } // Otherwise, it may be a unextractable key of PKCS#11, or |
| // a key we are not able to handle. |
| |
| return size; |
| } |
| |
| /** |
| * Returns whether the key is valid or not. |
| * <P> |
| * Note that this method is only apply to DHPublicKey at present. |
| * |
| * @param publicKey |
| * the key object, cannot be null |
| * |
| * @throws NullPointerException if {@code publicKey} is null |
| * @throws InvalidKeyException if {@code publicKey} is invalid |
| */ |
| public static final void validate(Key key) |
| throws InvalidKeyException { |
| if (key == null) { |
| throw new NullPointerException( |
| "The key to be validated cannot be null"); |
| } |
| |
| if (key instanceof DHPublicKey) { |
| validateDHPublicKey((DHPublicKey)key); |
| } |
| } |
| |
| |
| /** |
| * Returns whether the key spec is valid or not. |
| * <P> |
| * Note that this method is only apply to DHPublicKeySpec at present. |
| * |
| * @param keySpec |
| * the key spec object, cannot be null |
| * |
| * @throws NullPointerException if {@code keySpec} is null |
| * @throws InvalidKeyException if {@code keySpec} is invalid |
| */ |
| public static final void validate(KeySpec keySpec) |
| throws InvalidKeyException { |
| if (keySpec == null) { |
| throw new NullPointerException( |
| "The key spec to be validated cannot be null"); |
| } |
| |
| if (keySpec instanceof DHPublicKeySpec) { |
| validateDHPublicKey((DHPublicKeySpec)keySpec); |
| } |
| } |
| |
| /** |
| * Returns whether the specified provider is Oracle provider or not. |
| * <P> |
| * Note that this method is only apply to SunJCE and SunPKCS11 at present. |
| * |
| * @param providerName |
| * the provider name |
| * @return true if, and only if, the provider of the specified |
| * {@code providerName} is Oracle provider |
| */ |
| public static final boolean isOracleJCEProvider(String providerName) { |
| return providerName != null && (providerName.equals("SunJCE") || |
| providerName.startsWith("SunPKCS11")); |
| } |
| |
| /** |
| * Returns whether the Diffie-Hellman public key is valid or not. |
| * |
| * Per RFC 2631 and NIST SP800-56A, the following algorithm is used to |
| * validate Diffie-Hellman public keys: |
| * 1. Verify that y lies within the interval [2,p-1]. If it does not, |
| * the key is invalid. |
| * 2. Compute y^q mod p. If the result == 1, the key is valid. |
| * Otherwise the key is invalid. |
| */ |
| private static void validateDHPublicKey(DHPublicKey publicKey) |
| throws InvalidKeyException { |
| DHParameterSpec paramSpec = publicKey.getParams(); |
| |
| BigInteger p = paramSpec.getP(); |
| BigInteger g = paramSpec.getG(); |
| BigInteger y = publicKey.getY(); |
| |
| validateDHPublicKey(p, g, y); |
| } |
| |
| private static void validateDHPublicKey(DHPublicKeySpec publicKeySpec) |
| throws InvalidKeyException { |
| validateDHPublicKey(publicKeySpec.getP(), |
| publicKeySpec.getG(), publicKeySpec.getY()); |
| } |
| |
| private static void validateDHPublicKey(BigInteger p, |
| BigInteger g, BigInteger y) throws InvalidKeyException { |
| |
| // For better interoperability, the interval is limited to [2, p-2]. |
| BigInteger leftOpen = BigInteger.ONE; |
| BigInteger rightOpen = p.subtract(BigInteger.ONE); |
| if (y.compareTo(leftOpen) <= 0) { |
| throw new InvalidKeyException( |
| "Diffie-Hellman public key is too small"); |
| } |
| if (y.compareTo(rightOpen) >= 0) { |
| throw new InvalidKeyException( |
| "Diffie-Hellman public key is too large"); |
| } |
| |
| // Don't bother to check against the y^q mod p if safe primes are used. |
| } |
| } |
| |
