| /* |
| * 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 javax.crypto.Mac; |
| import javax.crypto.spec.SecretKeySpec; |
| import java.security.InvalidKeyException; |
| import java.security.NoSuchAlgorithmException; |
| import java.security.NoSuchProviderException; |
| import java.security.SecureRandomParameters; |
| import java.util.Arrays; |
| import java.util.Collections; |
| import java.util.List; |
| |
| public class HmacDrbg extends AbstractHashDrbg { |
| |
| private Mac mac; |
| |
| private String macAlg; |
| |
| private byte[] v; |
| private byte[] k; |
| |
| public HmacDrbg(SecureRandomParameters params) { |
| mechName = "HMAC_DRBG"; |
| configure(params); |
| } |
| |
| private void status() { |
| if (debug != null) { |
| debug.println(this, "V = " + hex(v)); |
| debug.println(this, "Key = " + hex(k)); |
| debug.println(this, "reseed counter = " + reseedCounter); |
| } |
| } |
| |
| // 800-90Ar1 10.1.2.2: HMAC_DRBG Update Process |
| private void update(List<byte[]> inputs) { |
| try { |
| // Step 1. K = HMAC (K, V || 0x00 || provided_data). |
| mac.init(new SecretKeySpec(k, macAlg)); |
| mac.update(v); |
| mac.update((byte) 0); |
| for (byte[] input: inputs) { |
| mac.update(input); |
| } |
| k = mac.doFinal(); |
| |
| // Step 2. V = HMAC (K, V). |
| mac.init(new SecretKeySpec(k, macAlg)); |
| v = mac.doFinal(v); |
| |
| if (!inputs.isEmpty()) { |
| // Step 4. K = HMAC (K, V || 0x01 || provided_data). |
| mac.update(v); |
| mac.update((byte) 1); |
| for (byte[] input: inputs) { |
| mac.update(input); |
| } |
| k = mac.doFinal(); |
| |
| // Step 5. V=HMAC(K,V). |
| mac.init(new SecretKeySpec(k, macAlg)); |
| v = mac.doFinal(v); |
| } // else Step 3 |
| |
| // Step 6. Return |
| } catch (InvalidKeyException e) { |
| throw new InternalError(e); |
| } |
| } |
| |
| /** |
| * This call, used by the constructors, instantiates the digest. |
| */ |
| @Override |
| protected void initEngine() { |
| macAlg = "HmacSHA" + algorithm.substring(4); |
| try { |
| /* |
| * Use the local SunJCE implementation to avoid native |
| * performance overhead. |
| */ |
| mac = Mac.getInstance(macAlg, "SunJCE"); |
| } catch (NoSuchProviderException | NoSuchAlgorithmException e) { |
| // Fallback to any available. |
| try { |
| mac = Mac.getInstance(macAlg); |
| } catch (NoSuchAlgorithmException exc) { |
| throw new InternalError( |
| "internal error: " + macAlg + " not available.", exc); |
| } |
| } |
| } |
| |
| // This method is used by both instantiation and reseeding. |
| @Override |
| protected final synchronized void hashReseedInternal(List<byte[]> input) { |
| |
| // 800-90Ar1 10.1.2.3: Instantiate Process. |
| // 800-90Ar1 10.1.2.4: Reseed Process. |
| if (v == null) { |
| k = new byte[outLen]; |
| v = new byte[outLen]; |
| Arrays.fill(v, (byte) 1); |
| } |
| |
| // Step 2: HMAC_DRBG_Update |
| update(input); |
| |
| // Step 3: reseed_counter = 1. |
| reseedCounter = 1; |
| //status(); |
| |
| // Step 4: Return |
| } |
| |
| /** |
| * Generates a user-specified number of random bytes. |
| * |
| * @param result the array to be filled in with random bytes. |
| */ |
| @Override |
| public synchronized void generateAlgorithm( |
| byte[] result, byte[] additionalInput) { |
| |
| if (debug != null) { |
| debug.println(this, "generateAlgorithm"); |
| } |
| |
| // 800-90Ar1 10.1.2.5: HMAC_DRBG_Generate Process |
| |
| // Step 1: Check reseed_counter. Will not fail. Already checked in |
| // AbstractDrbg#engineNextBytes. |
| |
| // Step 2. HMAC_DRBG_Update |
| if (additionalInput != null) { |
| update(Collections.singletonList(additionalInput)); |
| } |
| |
| // Step 3. temp = Null. |
| int pos = 0; |
| int len = result.length; |
| |
| // Step 4. Loop |
| while (len > 0) { |
| // Step 4.1 V = HMAC (Key, V). |
| try { |
| mac.init(new SecretKeySpec(k, macAlg)); |
| } catch (InvalidKeyException e) { |
| throw new InternalError(e); |
| } |
| v = mac.doFinal(v); |
| // Step 4.2 temp = temp || V. |
| System.arraycopy(v, 0, result, pos, |
| len > outLen ? outLen : len); |
| |
| len -= outLen; |
| if (len <= 0) { |
| // shortcut, so that pos needn't be updated |
| break; |
| } |
| pos += outLen; |
| } |
| |
| // Step 5: No need to truncate |
| |
| // Step 6. HMAC_DRBG_Update (additional_input, Key, V). |
| if (additionalInput != null) { |
| update(Collections.singletonList(additionalInput)); |
| } else { |
| update(Collections.emptyList()); |
| } |
| |
| // Step 7. reseed_counter = reseed_counter + 1. |
| reseedCounter++; |
| |
| //status(); |
| |
| // Step 8. Return |
| } |
| } |