我正在尝试使用SSLEngine来实现SSL握手，我既需要作为服务器也要作为客户端同时使用它，但是我被卡住了，无法弄清原因。
握手正确开始，交换了Hello，交换了密钥，但是随后我进入NEED_UNWRAP状态。
这是我正在使用的握手代码：
protected boolean doHandshake(InputStream inputStream, OutputStream outputStream, SSLEngine engine, Socket socket) throws IOException {
Log.d(TAG,"About to do handshake...");
Log.d(TAG,engine.getHandshakeStatus().toString());
int dataSize;
SSLEngineResult result;
Log.d(TAG,"Line 1");
HandshakeStatus handshakeStatus;
Log.d(TAG,"Line 2");
// NioSslPeer's fields myAppData and peerAppData are supposed to be large enough to hold all message data the peer
// will send and expects to receive from the other peer respectively. Since the messages to be exchanged will usually be less
// than 16KB long the capacity of these fields should also be smaller. Here we initialize these two local buffers
// to be used for the handshake, while keeping client's buffers at the same size.
if (socket!=null)
{
inputStream=socket.getInputStream();
outputStream=socket.getOutputStream();
}
Log.d(TAG,"Line 3");
int appBufferSize = engine.getSession().getApplicationBufferSize();
Log.d(TAG,"Line 4");
ByteBuffer myAppData = ByteBuffer.allocate(appBufferSize);
Log.d(TAG,"Line 5");
ByteBuffer peerAppData = ByteBuffer.allocate(appBufferSize);
Log.d(TAG,"Line 6");
try {
myNetData.clear();
peerNetData.clear();
}
catch (Exception e){Log.e(TAG,e.getMessage());}
Log.d(TAG,"Line 7");
Log.d(TAG,"Line 8");
handshakeStatus = engine.getHandshakeStatus();
Log.d(TAG,"Line 9");
Log.d(TAG,"Before the while: " + (handshakeStatus != SSLEngineResult.HandshakeStatus.FINISHED && handshakeStatus != SSLEngineResult.HandshakeStatus.NOT_HANDSHAKING));
byte[] buffer=new byte[16384];
while (handshakeStatus != SSLEngineResult.HandshakeStatus.FINISHED && handshakeStatus != SSLEngineResult.HandshakeStatus.NOT_HANDSHAKING) {
Log.d(TAG,handshakeStatus.toString());
switch (handshakeStatus) {
case NEED_UNWRAP:
Log.d(TAG,"Got here...");
buffer=new byte[16384];
peerAppData.clear();
int readdata=inputStream.read(buffer);
Log.d(TAG,"Read data amount: " + readdata);
if ( readdata < 0) {
Log.d(TAG,"No data....");
if (engine.isInboundDone() && engine.isOutboundDone()) {
return false;
}
try {
engine.closeInbound();
} catch (SSLException e) {
Log.e(TAG,"This engine was forced to close inbound, without having received the proper SSL/TLS close notification message from the peer, due to end of stream.");
}
engine.closeOutbound();
// After closeOutbound the engine will be set to WRAP state, in order to try to send a close message to the client.
handshakeStatus = engine.getHandshakeStatus();
break;
}
HackerService.bytesToHex(buffer);
peerNetData.put(buffer,6,readdata-6);
Log.d(TAG,"before data flipped...");
peerNetData.flip();
Log.d(TAG,"data flipped...");
try {
result = engine.unwrap(peerNetData, peerAppData);
Log.d(TAG,"data unwrapped...");
peerNetData.compact();
Log.d(TAG,"data compacted...");
handshakeStatus = result.getHandshakeStatus();
Log.d(TAG,"Handshake status: " + handshakeStatus);
} catch (SSLException sslException) {
Log.e(TAG,"A problem was encountered while processing the data that caused the SSLEngine to abort. Will try to properly close connection..." + sslException.getMessage());
engine.closeOutbound();
handshakeStatus = engine.getHandshakeStatus();
break;
}
switch (result.getStatus()) {
case OK:
break;
case BUFFER_OVERFLOW:
// Will occur when peerAppData's capacity is smaller than the data derived from peerNetData's unwrap.
peerAppData = enlargeApplicationBuffer(engine, peerAppData);
break;
case BUFFER_UNDERFLOW:
// Will occur either when no data was read from the peer or when the peerNetData buffer was too small to hold all peer's data.
peerNetData = handleBufferUnderflow(engine, peerNetData);
break;
case CLOSED:
if (engine.isOutboundDone()) {
return false;
} else {
engine.closeOutbound();
handshakeStatus = engine.getHandshakeStatus();
break;
}
default:
throw new IllegalStateException("Invalid SSL status: " + result.getStatus());
}
break;
case NEED_WRAP:
myNetData.clear();
Log.d(TAG,"Enetering need wrap");
try {
result = engine.wrap(myAppData, myNetData);
Log.d(TAG,"Got a result" + myAppData.toString());
handshakeStatus = result.getHandshakeStatus();
Log.d(TAG,"Handskes is: " + handshakeStatus.toString());
} catch (SSLException sslException) {
Log.e(TAG,"A problem was encountered while processing the data that caused the SSLEngine to abort. Will try to properly close connection...");
engine.closeOutbound();
handshakeStatus = engine.getHandshakeStatus();
break;
}
switch (result.getStatus()) {
case OK :
Log.d(TAG,"Case WRAP, OK");
myNetData.flip();
// while (myNetData.hasRemaining()) {
byte[] arr = new byte[myNetData.remaining()+6];
myNetData.get(arr,6,myNetData.remaining());
arr[0]=0;
arr[1]=3;
arr[2]=(byte) ((arr.length-4)/256);
arr[3]=(byte) ((arr.length-4)%256);
arr[4]=buffer[4];
arr[5]=buffer[5];
HackerService.bytesToHex(arr);
outputStream.write(arr);
// }
break;
case BUFFER_OVERFLOW:
Log.d(TAG,"Case WRAP,OverFlow");
// Will occur if there is not enough space in myNetData buffer to write all the data that would be generated by the method wrap.
// Since myNetData is set to session's packet size we should not get to this point because SSLEngine is supposed
// to produce messages smaller or equal to that, but a general handling would be the following:
myNetData = enlargePacketBuffer(engine, myNetData);
break;
case BUFFER_UNDERFLOW:
throw new SSLException("Buffer underflow occured after a wrap. I don't think we should ever get here.");
case CLOSED:
try {
Log.d(TAG,"Before WRAP FLIP");
myNetData.flip();
Log.d(TAG,"After WRAP FLIP");
while (myNetData.hasRemaining()) {
Log.d(TAG,myNetData.toString());
arr = new byte[myNetData.remaining()];
myNetData.get(arr);
outputStream.write(arr);
}
// At this point the handshake status will probably be NEED_UNWRAP so we make sure that peerNetData is clear to read.
peerNetData.clear();
} catch (Exception e) {
Log.e(TAG,"Failed to send server's CLOSE message due to socket channel's failure.");
handshakeStatus = engine.getHandshakeStatus();
}
break;
default:
throw new IllegalStateException("Invalid SSL status: " + result.getStatus());
}
break;
case NEED_TASK:
Log.d(TAG,"Need task");
Runnable task;
while ((task = engine.getDelegatedTask()) != null) {
executor.execute(task);
}
handshakeStatus = engine.getHandshakeStatus();
break;
case FINISHED:
break;
case NOT_HANDSHAKING:
break;
default:
throw new IllegalStateException("Invalid SSL status: " + handshakeStatus);
}
}
Log.d(TAG,"Handshake completed");
return true;
}
这是我的SSLEngine创建类：
public static SSLEngine Builder(Context context) throws KeyStoreException, CertificateException, NoSuchAlgorithmException, IOException, UnrecoverableKeyException, KeyManagementException {
InputStream openRawResource = context.getResources().openRawResource(context.getResources().getIdentifier("mykey", "raw", context.getPackageName()));
KeyStore instance = KeyStore.getInstance("PKCS12");
instance.load(openRawResource, "passcode".toCharArray());
KeyManagerFactory instance2 = KeyManagerFactory.getInstance(KeyManagerFactory.getDefaultAlgorithm());
instance2.init(instance, "passcode".toCharArray());
SSLContext instance3 = SSLContext.getInstance("TLSv1.2");
instance3.init(instance2.getKeyManagers(), new TrustManager[]{new TrustmanagerHelper()}, new SecureRandom());
SSLEngine createSSLEngine = instance3.createSSLEngine();
createSSLEngine.setNeedClientAuth(true);
return createSSLEngine;
}
当我尝试作为客户端进行握手时。从日志中可以看到，我从NEED_WRAP开始，将数据发送到服务器，状态到达NEED_UNWRAP（这是正确的）服务器响应，我解析了答案，没有任何错误，但是我没有前进到NEED_WRAP，而是陷入了NEED_UNWRAP。 ..
About to do handshake...
NEED_WRAP
Line 1
Line 2
Line 4
Line 5
Line 6
Line 7
Line 8
Line 9
Before the while: true
NEED_WRAP
Enetering need wrap
Got a resultjava.nio.HeapByteBuffer[pos=0 lim=16384 cap=16384]
Handskes is: NEED_UNWRAP
Case WRAP, OK
ByteTohex: 00030088000316030100810100007D03030E62BFCFF988.......
NEED_UNWRAP
Got here...
Read data amount: 2296 (THIS MATCHES THE NUMBER OF BYTES SENT BY THE SERVER!!!!)
ByteTohex: 000308F40003160303005B0200005703035B203DA285349B7C88A76CA6AA3.....
before data flipped...
data flipped...
data unwrapped...
data compacted...
Handshake status: NEED_UNWRAP
NEED_UNWRAP
Got here...
如果我尝试作为服务器进行握手，则日志看起来像这样。从日志中可以看到，第一次读取就可以了，我对客户端进行了响应，我从客户端获取了第二位数据，而不是使用NEED_WRAP并能够继续进行被击中的握手带有NEED_UNWRAP消息，但是当然没有更多数据要从客户端读取了。
About to do handshake...
NEED_UNWRAP
Line 1
Line 2
Line 3
Line 4
Line 5
Line 6
Line 7
Line 8
Line 9
Before the while: true
NEED_UNWRAP
Got here...
06-12 23:42:14.017 7523-7620/uk.co.borconi,emil.myapp D/MyApp: Read data amount: 297
06-12 23:42:14.020 7523-7620/uk.co.borconi,emil.myapp D/MyApp: ByteTohex: 00030125000316....
before data flipped...
data flipped...
06-12 23:42:14.029 7523-7620/uk.co.borconi,emil.myapp D/MyApp: data unwrapped...
data compacted...
Handshake status: NEED_WRAP
NEED_WRAP
Enetering need wrap
Got a resultjava.nio.HeapByteBuffer[pos=0 lim=16384 cap=16384]
Handskes is: NEED_UNWRAP
Case WRAP, OK
06-12 23:42:14.030 7523-7620/uk.co.borconi,emil.myapp D/MyApp: ByteTohex: 00030881000316.....
NEED_UNWRAP
Got here...
06-12 23:42:14.038 7523-7620/uk.co.borconi,emil.myapp D/MyApp: Read data amount: 132
06-12 23:42:14.039 7523-7620/uk.co.borconi,emil.myapp D/MyApp: ByteTohex: 00030080000316....
before data flipped...
data flipped...
06-12 23:42:14.040 7523-7620/uk.co.borconi,emil.myapp D/MyApp: data unwrapped...
data compacted...
Handshake status: NEED_UNWRAP
NEED_UNWRAP
Got here...
在发布之前，我确实查看过关于StackOverflow的一些类似问题，但是它们主要是关于顺序错误的问题，在这种情况下，我认为我是对的...我敢肯定，我确实缺少明显的问题，但是我只是似乎无法弄清楚...
最佳答案
经过两天的追寻，我终于找到了这里描述的问题：https://github.com/netty/netty/issues/5975
我发现我们围绕SSLEngine的基于流的包装器未读取
没有新的传入数据时，来自SSLEngine的所有传入数据
来自网络的数据，因此应用程序陷入等待状态
传入数据。经过一些调试后，我发现与netty的
openssl SSLEngine展开似乎会以较小的尺寸生成纯文本数据
块（可能是单个TLS帧），并继续缓冲其余
内部数据。 src缓冲区已完全消耗，但调用
再次使用空的src缓冲区解包仍将产生更多数据。
这与JDK SSLEngine所做的两点不同：
JDK SSLEngine一次消耗并产生尽可能多的数据，而openssl一次消耗较少的输出
JDK SSLEngine不会在两次调用之间在内部缓冲加密的数据，而是将其“放回”到src缓冲区中
因此，即使我的代码是“正确的”，我也需要执行多个循环，所以现在我的展开代码看起来像这样：
peerNetData.put(buffer,6,readdata-6);
Log.d(TAG,"before data flipped...");
peerNetData.flip();
Log.d(TAG,"data flipped...");
try {
do {
result = engine.unwrap(peerNetData, peerAppData);
Log.d(TAG,"data unwrapped...");
Log.d(TAG,"Handskes is: " + result.getHandshakeStatus().toString() +" Current Status: " +result.getStatus() + " Bytes consumed: " + result.bytesConsumed() + " bytes produce: " + result.bytesProduced());
} while (peerNetData.hasRemaining() || result.bytesProduced()>0);
peerNetData.compact();
Log.d(TAG,"data compacted...");
handshakeStatus = result.getHandshakeStatus();
Log.d(TAG,"Handshake status: " + handshakeStatus);
.....................................................