net: add a test to ensure that our TLS handshake doesn't get too large.

third_party/tlslite/tlslite/TLSConnection.py

 """
 MAIN CLASS FOR TLS LITE (START HERE!).
 """
 from __future__ import generators
 
 import socket
 from utils.compat import formatExceptionTrace
 from TLSRecordLayer import TLSRecordLayer
 from Session import Session
 from constants import *
@@ skipping 1090 matching lines @@
         self.version = settings.maxVersion
 
         #Get ClientHello
         for result in self._getMsg(ContentType.handshake,
                                    HandshakeType.client_hello):
             if result in (0,1):
                 yield result
             else:
                 break
         clientHello = result
+        self.client_hello_length = clientHello.client_hello_length
 
         #If client's version is too low, reject it
         if clientHello.client_version < settings.minVersion:
             self.version = settings.minVersion
             for result in self._sendError(\
                   AlertDescription.protocol_version,
                   "Too old version: %s" % str(clientHello.client_version)):
                 yield result
 
         #If tlsIntolerant is nonzero, reject certain TLS versions.
@@ skipping 515 matching lines @@
         if len(publicKey) < settings.minKeySize:
             for result in self._sendError(AlertDescription.handshake_failure,
                     "Other party's public key too small: %d" % len(publicKey)):
                 yield result
         if len(publicKey) > settings.maxKeySize:
             for result in self._sendError(AlertDescription.handshake_failure,
                     "Other party's public key too large: %d" % len(publicKey)):
                 yield result
 
         yield publicKey, certChain