fixed rare fatal racing condition in SSLSocketChannel2 ( TooTallNate#190 )

Davidiusdadi · Davidiusdadi · commit 8471a3542029 · 2013-07-25T00:23:43.000+02:00
diff --git a/src/main/java/org/java_websocket/SSLSocketChannel2.java b/src/main/java/org/java_websocket/SSLSocketChannel2.java
@@ -158,7 +158,6 @@ private synchronized ByteBuffer unwrap() throws SSLException {
 			rem = inData.remaining();
 			readEngineResult = sslEngine.unwrap( inCrypt, inData );
 		} while ( readEngineResult.getStatus() == SSLEngineResult.Status.OK && ( rem != inData.remaining() || sslEngine.getHandshakeStatus() == HandshakeStatus.NEED_UNWRAP ) );
-
 		inData.flip();
 		return inData;
 	}
@@ -226,10 +225,16 @@ public int read( ByteBuffer dst ) throws IOException {
 				}
 			}
 		}
+		/* 1. When "dst" is smaller than "inData" readRemaining will fill "dst" with data decoded in a previous read call.
+		 * 2. When "inCrypt" contains more data than "inData" has remaining space, unwrap has to be called on more time(readRemaining)
+		 */
 		int purged = readRemaining( dst );
 		if( purged != 0 )
 			return purged;
 
+		/* We only continue when we really need more data from the network.
+		 * Thats the case if inData is empty or inCrypt holds to less data than necessary for decryption
+		 */
 		assert ( inData.position() == 0 );
 		inData.clear();
 
@@ -238,7 +243,7 @@ public int read( ByteBuffer dst ) throws IOException {
 		else
 			inCrypt.compact();
 
-		if( ( isBlocking() && inCrypt.position() == 0 ) || readEngineResult.getStatus() == Status.BUFFER_UNDERFLOW )
+		if( isBlocking() || readEngineResult.getStatus() == Status.BUFFER_UNDERFLOW )
 			if( socketChannel.read( inCrypt ) == -1 ) {
 				return -1;
 			}

Original file line number	Diff line number	Diff line change
`@@ -158,7 +158,6 @@ private synchronized ByteBuffer unwrap() throws SSLException {`
`158`	`158`	`rem = inData.remaining();`
`159`	`159`	`readEngineResult = sslEngine.unwrap( inCrypt, inData );`
`160`	`160`	`} while ( readEngineResult.getStatus() == SSLEngineResult.Status.OK && ( rem != inData.remaining() \|\| sslEngine.getHandshakeStatus() == HandshakeStatus.NEED_UNWRAP ) );`
`161`		`-`
`162`	`161`	`inData.flip();`
`163`	`162`	`return inData;`
`164`	`163`	`}`
`@@ -226,10 +225,16 @@ public int read( ByteBuffer dst ) throws IOException {`
`226`	`225`	`}`
`227`	`226`	`}`
`228`	`227`	`}`
	`228`	`+ /* 1. When "dst" is smaller than "inData" readRemaining will fill "dst" with data decoded in a previous read call.`
	`229`	`+ * 2. When "inCrypt" contains more data than "inData" has remaining space, unwrap has to be called on more time(readRemaining)`
	`230`	`+ */`
`229`	`231`	`int purged = readRemaining( dst );`
`230`	`232`	`if( purged != 0 )`
`231`	`233`	`return purged;`
`232`	`234`
	`235`	`+ /* We only continue when we really need more data from the network.`
	`236`	`+ * Thats the case if inData is empty or inCrypt holds to less data than necessary for decryption`
	`237`	`+ */`
`233`	`238`	`assert ( inData.position() == 0 );`
`234`	`239`	`inData.clear();`
`235`	`240`
`@@ -238,7 +243,7 @@ public int read( ByteBuffer dst ) throws IOException {`
`238`	`243`	`else`
`239`	`244`	`inCrypt.compact();`
`240`	`245`
`241`		`- if( ( isBlocking() && inCrypt.position() == 0 ) \|\| readEngineResult.getStatus() == Status.BUFFER_UNDERFLOW )`
	`246`	`+ if( isBlocking() \|\| readEngineResult.getStatus() == Status.BUFFER_UNDERFLOW )`
`242`	`247`	`if( socketChannel.read( inCrypt ) == -1 ) {`
`243`	`248`	`return -1;`
`244`	`249`	`}`