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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-family:"Courier New"">I have encountered a problem with EAP-FAST PACs when switching our implementation of OpenSSL from a context that supports TLSv1.0 only to a context that supports negotiation
to the highest available TLS version.<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-family:"Courier New"">For EAP-FAST the PAC opaque is loaded into the SSL tlsext_session_ticket using the SSL_set_session_ticket_ext method during initialization of the SSL connection.<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-family:"Courier New"">When the SSL context is set using TLSV1_client_method (TLS v1.0), the
</span><span style="font-size:10.0pt;font-family:"Courier New"">ssl3_client_hello method is invoked for the client hello message which calls ssl_get_new_session if SSL session is NULL.
</span><span style="font-family:"Courier New"">The </span><span style="font-size:10.0pt;font-family:"Courier New"">ssl3_client_hello method eventually calls ssl_add_clienthello_tlsext which will initialize the SSL session tlsext_tick structure as long as the
SSL structure contains a session that is not NULL.<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Courier New"">When the
</span><span style="font-family:"Courier New"">SSL context is set using SSLv23_client_method, the
</span><span style="font-size:10.0pt;font-family:"Courier New"">ssl23_client_hello method is invoked for the client hello message which does not call ssl_get_new_session (the call is commented out) before the ssl_add_clienthello_tlsext is called. In this scenario
the SSL session is NULL, so when ssl_add_clienthello_tlsext is called it does not initialize the SSL session tlsext_tick structure. This results in the EAP-FAST PAC not being loaded into the TLS session ticket extension when using the methods that support
negotiation of the highest available SSL/TLS version.<o:p></o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-size:10.0pt;font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal" style="text-autospace:none"><span style="font-family:"Courier New"">In order for TLS session ticket extension to work with the SSLv23_client_method's it seems that the ssl23_client_hello method should add a new session object to the SSL
connection when there is none, similar to what is done in the ssl3_client_hello method.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New""><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-family:"Courier New"">Ian McFadries<o:p></o:p></span></p>
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