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                                Secure connection

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1. Init
-------

1. To wrap existing non-encrypted connection into encrypted one (TLS) use
   one of SecureConnectionCreate() functions family.

  Input non-encrypted connection can be defined as:
  - FD pair
  - socket
  - {read, write} callbacks
  

2. To start TLS session:
------------------------

   Server needs:
   - certificate file (cert parameter) 
   - private key file (privKey paramter)
   
   Client needs:
   - nothing (cert and privKey parameters should be NULL)
   

3. Server skeleton code:
------------------------

   sc = SecureConnectionCreate(SECURE_INTENT_SERVER, ..., cert, privateKey);

   sc -> read(...);
   sc -> write(...);   
   
   sc -> release();
   

4. Client skeleton code:
------------------------

   sc = SecureConnectionCreate(SECURE_INTENT_CLIENT, ..., NULL, NULL);
   
   sc -> write(...);
   sc -> read(...);
   
   sc -> release();