| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| */ |
| package org.apache.sshd.common.signature; |
| |
| import java.io.StreamCorruptedException; |
| import java.math.BigInteger; |
| |
| import org.apache.sshd.common.cipher.ECCurves; |
| import org.apache.sshd.common.util.Pair; |
| import org.apache.sshd.common.util.ValidateUtils; |
| import org.apache.sshd.common.util.buffer.Buffer; |
| import org.apache.sshd.common.util.buffer.ByteArrayBuffer; |
| import org.apache.sshd.common.util.io.DERParser; |
| import org.apache.sshd.common.util.io.DERWriter; |
| |
| /** |
| * Signature algorithm for EC keys using ECDSA. |
| * |
| * @author <a href="mailto:dev@mina.apache.org">Apache MINA SSHD Project</a> |
| * @see <A HREF="http://tools.ietf.org/html/rfc3278#section-8.2">RFC3278 section 8.2</A> |
| */ |
| public class SignatureECDSA extends AbstractSignature { |
| public static class SignatureECDSA256 extends SignatureECDSA { |
| public static final String DEFAULT_ALGORITHM = "SHA256withECDSA"; |
| |
| public SignatureECDSA256() { |
| super(DEFAULT_ALGORITHM); |
| } |
| } |
| |
| public static class SignatureECDSA384 extends SignatureECDSA { |
| public static final String DEFAULT_ALGORITHM = "SHA384withECDSA"; |
| |
| public SignatureECDSA384() { |
| super(DEFAULT_ALGORITHM); |
| } |
| } |
| |
| public static class SignatureECDSA521 extends SignatureECDSA { |
| public static final String DEFAULT_ALGORITHM = "SHA512withECDSA"; |
| |
| public SignatureECDSA521() { |
| super(DEFAULT_ALGORITHM); |
| } |
| } |
| |
| protected SignatureECDSA(String algo) { |
| super(algo); |
| } |
| |
| @Override |
| public byte[] sign() throws Exception { |
| java.security.Signature signature = ValidateUtils.checkNotNull(getSignature(), "Signature not initialized"); |
| byte[] sig = signature.sign(); |
| |
| try (DERParser parser = new DERParser(sig)) { |
| int type = parser.read(); |
| if (type != 0x30) { |
| throw new StreamCorruptedException("Invalid signature format - not a DER SEQUENCE: 0x" + Integer.toHexString(type)); |
| } |
| |
| // length of remaining encoding of the 2 integers |
| int remainLen = parser.readLength(); |
| /* |
| * There are supposed to be 2 INTEGERs, each encoded with: |
| * |
| * - one byte representing the fact that it is an INTEGER |
| * - one byte of the integer encoding length |
| * - at least one byte of integer data (zero length is not an option) |
| */ |
| if (remainLen < (2 * 3)) { |
| throw new StreamCorruptedException("Invalid signature format - not enough encoded data length: " + remainLen); |
| } |
| |
| BigInteger r = parser.readBigInteger(); |
| BigInteger s = parser.readBigInteger(); |
| // Write the <r,s> to its own types writer. |
| Buffer rsBuf = new ByteArrayBuffer(); |
| rsBuf.putMPInt(r); |
| rsBuf.putMPInt(s); |
| |
| return rsBuf.getCompactData(); |
| } |
| } |
| |
| @Override |
| public boolean verify(byte[] sig) throws Exception { |
| byte[] data = sig; |
| Pair<String, byte[]> encoding = extractEncodedSignature(data); |
| if (encoding != null) { |
| String keyType = encoding.getFirst(); |
| ECCurves curve = ECCurves.fromKeyType(keyType); |
| ValidateUtils.checkNotNull(curve, "Unknown curve type: %s", keyType); |
| data = encoding.getSecond(); |
| } |
| |
| Buffer rsBuf = new ByteArrayBuffer(data); |
| byte[] rArray = rsBuf.getMPIntAsBytes(); |
| byte[] rEncoding; |
| try (DERWriter w = new DERWriter(rArray.length + 4)) { // in case length > 0x7F |
| w.writeBigInteger(rArray); |
| rEncoding = w.toByteArray(); |
| } |
| |
| byte[] sArray = rsBuf.getMPIntAsBytes(); |
| byte[] sEncoding; |
| try (DERWriter w = new DERWriter(sArray.length + 4)) { // in case length > 0x7F |
| w.writeBigInteger(sArray); |
| sEncoding = w.toByteArray(); |
| } |
| |
| int remaining = rsBuf.available(); |
| if (remaining != 0) { |
| throw new StreamCorruptedException("Signature had padding - remaining=" + remaining); |
| } |
| |
| int length = rEncoding.length + sEncoding.length; |
| byte[] encoded; |
| try (DERWriter w = new DERWriter(1 + length + 4)) { // in case length > 0x7F |
| w.write(0x30); // SEQUENCE |
| w.writeLength(length); |
| w.write(rEncoding); |
| w.write(sEncoding); |
| encoded = w.toByteArray(); |
| } |
| |
| return doVerify(encoded); |
| } |
| } |