netconf/callhome-protocol/src/main/java/org/opendaylight/netconf/callhome/protocol/AuthorizedKeysDecoder.java

   1 /*
   2  * Copyright (c) 2016 Brocade Communication Systems and others.  All rights reserved.
   3  *
   4  * This program and the accompanying materials are made available under the
   5  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   6  * and is available at http://www.eclipse.org/legal/epl-v10.html
   7  */
   8 package org.opendaylight.netconf.callhome.protocol;
   9
  10 import java.io.ByteArrayOutputStream;
  11 import java.io.DataOutputStream;
  12 import java.io.IOException;
  13 import java.math.BigInteger;
  14 import java.security.KeyFactory;
  15 import java.security.NoSuchAlgorithmException;
  16 import java.security.NoSuchProviderException;
  17 import java.security.PublicKey;
  18 import java.security.interfaces.DSAParams;
  19 import java.security.interfaces.DSAPublicKey;
  20 import java.security.interfaces.RSAPublicKey;
  21 import java.security.spec.DSAPublicKeySpec;
  22 import java.security.spec.ECPoint;
  23 import java.security.spec.ECPublicKeySpec;
  24 import java.security.spec.InvalidKeySpecException;
  25 import java.security.spec.RSAPublicKeySpec;
  26 import java.util.Arrays;
  27 import java.util.HashMap;
  28 import java.util.Map;
  29 import org.apache.sshd.common.util.Base64;
  30 import org.apache.sshd.common.util.SecurityUtils;
  31 import org.bouncycastle.jcajce.provider.asymmetric.ec.BCECPublicKey;
  32 import org.bouncycastle.jce.ECNamedCurveTable;
  33 import org.bouncycastle.jce.ECPointUtil;
  34 import org.bouncycastle.jce.spec.ECNamedCurveParameterSpec;
  35 import org.bouncycastle.jce.spec.ECNamedCurveSpec;
  36
  37 /**
  38  * FIXME: This should be probably located at AAA library.
  39  */
  40 public class AuthorizedKeysDecoder {
  41
  42     private static final String KEY_FACTORY_TYPE_RSA = "RSA";
  43     private static final String KEY_FACTORY_TYPE_DSA = "DSA";
  44     private static final String KEY_FACTORY_TYPE_ECDSA = "EC";
  45
  46     private static Map<String, String> ECDSA_CURVES = new HashMap<>();
  47
  48     static {
  49         ECDSA_CURVES.put("nistp256", "secp256r1");
  50         ECDSA_CURVES.put("nistp384", "secp384r1");
  51         ECDSA_CURVES.put("nistp512", "secp512r1");
  52     }
  53
  54     private static String ECDSA_SUPPORTED_CURVE_NAME = "nistp256";
  55     private static String ECDSA_SUPPORTED_CURVE_NAME_SPEC = ECDSA_CURVES.get(ECDSA_SUPPORTED_CURVE_NAME);
  56
  57     private static final String KEY_TYPE_RSA = "ssh-rsa";
  58     private static final String KEY_TYPE_DSA = "ssh-dss";
  59     private static final String KEY_TYPE_ECDSA = "ecdsa-sha2-" + ECDSA_SUPPORTED_CURVE_NAME;
  60
  61     private byte[] bytes = new byte[0];
  62     private int pos = 0;
  63
  64     public PublicKey decodePublicKey(String keyLine)
  65             throws InvalidKeySpecException, NoSuchAlgorithmException, NoSuchProviderException {
  66
  67         // look for the Base64 encoded part of the line to decode
  68         // both ssh-rsa and ssh-dss begin with "AAAA" due to the length bytes
  69         bytes = Base64.decodeBase64(keyLine.getBytes());
  70         if (bytes.length == 0) {
  71             throw new IllegalArgumentException("No Base64 part to decode in " + keyLine);
  72         }
  73
  74         pos = 0;
  75
  76         String type = decodeType();
  77         if (type.equals(KEY_TYPE_RSA)) {
  78             return decodeAsRSA();
  79         }
  80
  81         if (type.equals(KEY_TYPE_DSA)) {
  82             return decodeAsDSA();
  83         }
  84
  85         if (type.equals(KEY_TYPE_ECDSA)) {
  86             return decodeAsEcDSA();
  87         }
  88
  89         throw new IllegalArgumentException("Unknown decode key type " + type + " in " + keyLine);
  90     }
  91
  92     private PublicKey decodeAsEcDSA()
  93             throws NoSuchAlgorithmException, InvalidKeySpecException, NoSuchProviderException {
  94         KeyFactory ecdsaFactory = SecurityUtils.getKeyFactory(KEY_FACTORY_TYPE_ECDSA);
  95
  96         ECNamedCurveParameterSpec spec256r1 = ECNamedCurveTable.getParameterSpec(ECDSA_SUPPORTED_CURVE_NAME_SPEC);
  97         ECNamedCurveSpec params256r1 = new ECNamedCurveSpec(
  98             ECDSA_SUPPORTED_CURVE_NAME_SPEC, spec256r1.getCurve(), spec256r1.getG(), spec256r1.getN());
  99         // copy last 65 bytes from ssh key.
 100         ECPoint point = ECPointUtil.decodePoint(params256r1.getCurve(), Arrays.copyOfRange(bytes, 39, bytes.length));
 101         ECPublicKeySpec pubKeySpec = new ECPublicKeySpec(point, params256r1);
 102
 103         return ecdsaFactory.generatePublic(pubKeySpec);
 104     }
 105
 106     private PublicKey decodeAsDSA() throws NoSuchAlgorithmException, InvalidKeySpecException, NoSuchProviderException {
 107         KeyFactory dsaFactory = SecurityUtils.getKeyFactory(KEY_FACTORY_TYPE_DSA);
 108         BigInteger prime = decodeBigInt();
 109         BigInteger subPrime = decodeBigInt();
 110         BigInteger base = decodeBigInt();
 111         BigInteger publicKey = decodeBigInt();
 112         DSAPublicKeySpec spec = new DSAPublicKeySpec(publicKey, prime, subPrime, base);
 113
 114         return dsaFactory.generatePublic(spec);
 115     }
 116
 117     private PublicKey decodeAsRSA() throws NoSuchAlgorithmException, InvalidKeySpecException, NoSuchProviderException {
 118         KeyFactory rsaFactory = SecurityUtils.getKeyFactory(KEY_FACTORY_TYPE_RSA);
 119         BigInteger exponent = decodeBigInt();
 120         BigInteger modulus = decodeBigInt();
 121         RSAPublicKeySpec spec = new RSAPublicKeySpec(modulus, exponent);
 122
 123         return rsaFactory.generatePublic(spec);
 124     }
 125
 126     private String decodeType() {
 127         int len = decodeInt();
 128         String type = new String(bytes, pos, len);
 129         pos += len;
 130         return type;
 131     }
 132
 133     private int decodeInt() {
 134         return ((bytes[pos++] & 0xFF) << 24) | ((bytes[pos++] & 0xFF) << 16)
 135                 | ((bytes[pos++] & 0xFF) << 8) | (bytes[pos++] & 0xFF);
 136     }
 137
 138     private BigInteger decodeBigInt() {
 139         int len = decodeInt();
 140         byte[] bigIntBytes = new byte[len];
 141         System.arraycopy(bytes, pos, bigIntBytes, 0, len);
 142         pos += len;
 143         return new BigInteger(bigIntBytes);
 144     }
 145
 146     public static String encodePublicKey(PublicKey publicKey) throws IOException {
 147         String publicKeyEncoded;
 148         ByteArrayOutputStream byteOs = new ByteArrayOutputStream();
 149         if (publicKey.getAlgorithm().equals(KEY_FACTORY_TYPE_RSA)) {
 150             RSAPublicKey rsaPublicKey = (RSAPublicKey) publicKey;
 151             DataOutputStream dout = new DataOutputStream(byteOs);
 152             dout.writeInt(KEY_TYPE_RSA.getBytes().length);
 153             dout.write(KEY_TYPE_RSA.getBytes());
 154             dout.writeInt(rsaPublicKey.getPublicExponent().toByteArray().length);
 155             dout.write(rsaPublicKey.getPublicExponent().toByteArray());
 156             dout.writeInt(rsaPublicKey.getModulus().toByteArray().length);
 157             dout.write(rsaPublicKey.getModulus().toByteArray());
 158         } else if (publicKey.getAlgorithm().equals(KEY_FACTORY_TYPE_DSA)) {
 159             DSAPublicKey dsaPublicKey = (DSAPublicKey) publicKey;
 160             DSAParams dsaParams = dsaPublicKey.getParams();
 161             DataOutputStream dout = new DataOutputStream(byteOs);
 162             dout.writeInt(KEY_TYPE_DSA.getBytes().length);
 163             dout.write(KEY_TYPE_DSA.getBytes());
 164             dout.writeInt(dsaParams.getP().toByteArray().length);
 165             dout.write(dsaParams.getP().toByteArray());
 166             dout.writeInt(dsaParams.getQ().toByteArray().length);
 167             dout.write(dsaParams.getQ().toByteArray());
 168             dout.writeInt(dsaParams.getG().toByteArray().length);
 169             dout.write(dsaParams.getG().toByteArray());
 170             dout.writeInt(dsaPublicKey.getY().toByteArray().length);
 171             dout.write(dsaPublicKey.getY().toByteArray());
 172         } else if (publicKey.getAlgorithm().equals(KEY_FACTORY_TYPE_ECDSA)) {
 173             BCECPublicKey ecPublicKey = (BCECPublicKey) publicKey;
 174             DataOutputStream dout = new DataOutputStream(byteOs);
 175             dout.writeInt(KEY_TYPE_ECDSA.getBytes().length);
 176             dout.write(KEY_TYPE_ECDSA.getBytes());
 177             dout.writeInt(ECDSA_SUPPORTED_CURVE_NAME.getBytes().length);
 178             dout.write(ECDSA_SUPPORTED_CURVE_NAME.getBytes());
 179
 180             byte[] coordX = ecPublicKey.getQ().getAffineXCoord().getEncoded();
 181             byte[] coordY = ecPublicKey.getQ().getAffineYCoord().getEncoded();
 182             dout.writeInt(coordX.length + coordY.length + 1);
 183             dout.writeByte(0x04);
 184             dout.write(coordX);
 185             dout.write(coordY);
 186         } else {
 187             throw new IllegalArgumentException("Unknown public key encoding: " + publicKey.getAlgorithm());
 188         }
 189         publicKeyEncoded = new String(Base64.encodeBase64(byteOs.toByteArray()));
 190         return publicKeyEncoded;
 191     }
 192 }