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<p class="MsoNormal"><span style="color:#1F497D">Hi Folks,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">I am using Squid as a HTTPS interception proxy. When I try to access https://www.pcmag.com , (which is supposed to be bumped in my environment ), I get
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">“unable to forward request at this time” even though the website is perfectly accessible outside of the proxy.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">A packet capture suggests that after Client Hello -> ServerHello -> ServerCertificate,Server Key Exchange, ServerHelloDone, the remote server just sends a FIN,ACK packet, killing off the TCP connection. Nothing
else looks out of the ordinary. ( Without squid, firefox successfully opens the site and the negotiation is TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256, TLS1.2)<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">The only weird thing that stands out about that website is that the list of SubjectAlternateNames is huge. Could this be a possible bug with Squid ?<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">My TLS options in Squid.conf :<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">tls_outgoing_options cafile=/etc/pki/tls/certs/ca-bundle.crt \<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"> options=NO_SSLv3,SINGLE_DH_USE,SINGLE_ECDH_USE \<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"> cipher=HIGH:!RC4:!aNULL:!eNULL:!LOW:!3DES:!MD5:!EXP:!PSK:!SRP:!DSS:!EXPORT:!DES:!aECDH:!EDH-DSS-DES-CBC3-SHA:!EDH-RSA-DES-CBC3-SHA:!KRB5-DES-CBC3-SHA<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">https_port : <o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">https_port 23129 intercept ssl-bump \<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"> generate-host-certificates=on \<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"> dynamic_cert_mem_cache_size=4MB \<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"> cert=/etc/squid/InternetCA/InternetCA.pem \<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"> key=/etc/squid/InternetCA/InternetCA.key \<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"> tls-cafile=/etc/squid/InternetCA/InternetCA.chain.pem \<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"> capath=/etc/pki/tls/certs/certs.d \<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"> options=NO_SSLv3,SINGLE_DH_USE,SINGLE_ECDH_USE \<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"> tls-dh=prime256v1:/etc/squid/dhparam.pem<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Please advise.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Regards,<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:#1F497D">Sarfaraz<o:p></o:p></span></p>
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