Add TLS-SRP (RFC 5054) support

third_party/tlslite/tlslite/messages.py

 """Classes representing TLS messages."""
 
 from utils.compat import *
 from utils.cryptomath import *
 from errors import *
 from utils.codec import *
 from constants import *
 from X509 import X509
 from X509CertChain import X509CertChain
 
@@ skipping 152 matching lines @@
             self.random = p.getFixBytes(32)
             self.session_id = p.getVarBytes(1)
             self.cipher_suites = p.getVarList(2, 2)
             self.compression_methods = p.getVarList(1, 1)
             if not p.atLengthCheck():
                 totalExtLength = p.get(2)
                 soFar = 0
                 while soFar != totalExtLength:
                     extType = p.get(2)
                     extLength = p.get(2)
-                    if extType == 6:
+                    if extType == ClientHelloExtension.srp:
                         self.srp_username = bytesToString(p.getVarBytes(1))
                     elif extType == 7:
                         self.certificate_types = p.getVarList(1, 1)
                     else:
                         p.getFixBytes(extLength)
                     soFar += 4 + extLength
             p.stopLengthCheck()
         return self
 
     def write(self, trial=False):
@@ skipping 13 matching lines @@
             extLength += 5 + len(self.srp_username)
         if extLength > 0:
             w.add(extLength, 2)
 
         if self.certificate_types and self.certificate_types != \
                 [CertificateType.x509]:
             w.add(7, 2)
             w.add(len(self.certificate_types)+1, 2)
             w.addVarSeq(self.certificate_types, 1, 1)
         if self.srp_username:
-            w.add(6, 2)
+            w.add(ClientHelloExtension.srp, 2)
             w.add(len(self.srp_username)+1, 2)
             w.addVarSeq(stringToBytes(self.srp_username), 1, 1)
 
         return HandshakeMsg.postWrite(self, w, trial)
 
 
 class ServerHello(HandshakeMsg):
     def __init__(self):
         self.contentType = ContentType.handshake
         self.server_version = (0,0)
@@ skipping 357 matching lines @@
     def create(self, bytes):
         self.bytes = bytes
         return self
 
     def parse(self, p):
         self.bytes = p.bytes
         return self
 
     def write(self):
         return self.bytes