Fixed bug on sock_read. It returns 0 when an error reading occurs, and this situation was not being controlled.

src/tls_schannel.c

@@ -454,6 +454,12 @@ int tls_read(tls_t *tls, void * const buff, const size_t len)
     /* next, top up our recv buffer */
     bytes = sock_read(tls->sock, tls->recvbuffer + tls->recvbufferpos,
 		      tls->recvbuffermaxlen - tls->recvbufferpos);
+			  
+	if (bytes == 0)
+	{
+		tls->lasterror = WSAETIMEDOUT;
+		return -1;
+	}				  
 
     if (bytes == -1) {
 	if (!tls_is_recoverable(sock_error())) {