Home | History | Annotate | Download | only in handshake 
      1 /*
      2  * Copyright (C) 2014 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.TlsProtocolVersion;
     20 import libcore.tlswire.util.IoUtils;
     21 import java.io.ByteArrayInputStream;
     22 import java.io.DataInput;
     23 import java.io.DataInputStream;
     24 import java.io.EOFException;
     25 import java.io.IOException;
     26 import java.math.BigInteger;
     27 import java.util.ArrayList;
     28 import java.util.List;
     29 
     30 /**
     31  * {@link ClientHello} {@link HandshakeMessage} from TLS 1.2 RFC 5246.
     32  */
     33 public class ClientHello extends HandshakeMessage {
     34     public TlsProtocolVersion clientVersion;
     35     public byte[] random;
     36     public byte[] sessionId;
     37     public List<CipherSuite> cipherSuites;
     38     public List<CompressionMethod> compressionMethods;
     39 
     40     /** Extensions or {@code null} for no extensions. */
     41     public List<HelloExtension> extensions;
     42 
     43     @Override
     44     protected void parseBody(DataInput in) throws IOException {
     45         clientVersion = TlsProtocolVersion.read(in);
     46         random = new byte[32];
     47         in.readFully(random);
     48         sessionId = IoUtils.readTlsVariableLengthByteVector(in, 32);
     49         int[] cipherSuiteCodes = IoUtils.readTlsVariableLengthUnsignedShortVector(in, 0xfffe);
     50         cipherSuites = new ArrayList<CipherSuite>(cipherSuiteCodes.length);
     51         for (int i = 0; i < cipherSuiteCodes.length; i++) {
     52             cipherSuites.add(CipherSuite.valueOf(cipherSuiteCodes[i]));
     53         }
     54         byte[] compressionMethodCodes = IoUtils.readTlsVariableLengthByteVector(in, 0xff);
     55         compressionMethods = new ArrayList<CompressionMethod>(compressionMethodCodes.length);
     56         for (int i = 0; i < compressionMethodCodes.length; i++) {
     57             int code = compressionMethodCodes[i] & 0xff;
     58             compressionMethods.add(CompressionMethod.valueOf(code));
     59         }
     60 
     61         int extensionsSectionSize;
     62         try {
     63             extensionsSectionSize = in.readUnsignedShort();
     64         } catch (EOFException e) {
     65             // No extensions present
     66             extensionsSectionSize = 0;
     67         }
     68 
     69         if (extensionsSectionSize > 0) {
     70             extensions = new ArrayList<HelloExtension>();
     71             byte[] extensionsBytes = new byte[extensionsSectionSize];
     72             in.readFully(extensionsBytes);
     73             ByteArrayInputStream extensionsIn = new ByteArrayInputStream(extensionsBytes);
     74             DataInput extensionsDataIn = new DataInputStream(extensionsIn);
     75             while (extensionsIn.available() > 0) {
     76                 try {
     77                     extensions.add(HelloExtension.read(extensionsDataIn));
     78                 } catch (IOException e) {
     79                     throw new IOException(
     80                             "Failed to read HelloExtension #" + (extensions.size() + 1));
     81                 }
     82             }
     83         }
     84     }
     85 
     86     public HelloExtension findExtensionByType(int extensionType) {
     87         if (extensions == null) {
     88             return null;
     89         }
     90         for (HelloExtension extension : extensions) {
     91             if (extension.type == extensionType) {
     92                 return extension;
     93             }
     94         }
     95         return null;
     96     }
     97 
     98     @Override
     99     public String toString() {
    100         return "ClientHello{client version: " + clientVersion
    101                 + ", random: " + new BigInteger(1, random).toString(16)
    102                 + ", sessionId: " + new BigInteger(1, sessionId).toString(16)
    103                 + ", cipher suites: " + cipherSuites
    104                 + ", compression methods: " + compressionMethods
    105                 + ((extensions != null) ? (", extensions: " + String.valueOf(extensions)) : "")
    106                 + "}";
    107     }
    108 }
    109