1 /* 2 * Copyright (C) 2016 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package libcore.tlswire.handshake; 18 19 import libcore.tlswire.util.IoUtils; 20 import java.io.ByteArrayInputStream; 21 import java.io.DataInputStream; 22 import java.io.IOException; 23 import java.util.ArrayList; 24 import java.util.List; 25 26 /** 27 * {@code elliptic_curves} {@link HelloExtension} from RFC 4492 section 5.1.1. 28 */ 29 public class EllipticCurvesHelloExtension extends HelloExtension { 30 public List<EllipticCurve> supported; 31 public boolean wellFormed; 32 33 @Override 34 protected void parseData() throws IOException { 35 byte[] ellipticCurvesListBytes = IoUtils.readTlsVariableLengthByteVector( 36 new DataInputStream(new ByteArrayInputStream(data)), 0xffff); 37 ByteArrayInputStream ellipticCurvesListIn = new ByteArrayInputStream(ellipticCurvesListBytes); 38 DataInputStream in = new DataInputStream(ellipticCurvesListIn); 39 wellFormed = (ellipticCurvesListIn.available() % 2) == 0; 40 supported = new ArrayList<EllipticCurve>(ellipticCurvesListIn.available() / 2); 41 while (ellipticCurvesListIn.available() >= 2) { 42 int curve_id = in.readUnsignedShort(); 43 supported.add(EllipticCurve.fromIdentifier(curve_id)); 44 } 45 } 46 47 @Override 48 public String toString() { 49 StringBuilder sb = new StringBuilder("HelloExtension{type: elliptic_curves, wellFormed: "); 50 sb.append(wellFormed); 51 sb.append(", supported: "); 52 sb.append(supported); 53 sb.append('}'); 54 return sb.toString(); 55 } 56 } 57
