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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal>Hey Dev Team,<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Long before SSL-BUMP got to what it is now I had a question in my mind:<o:p></o:p></p><p class=MsoNormal>What about connections on intercepted port which are either non TLS/SSL or <br>when squid had some server or client negotiation issues?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The first issue with TLS connections is that if for any reason the proxy <br>didn’t managed to negotiate and establish a TLS connection with the server, the client is STUCK.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I cannot touch TLS related code due to obviates reasons but I believe it’s trivial to have:<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span dir=LTR></span>Proxy side “retries” toward the TLS server<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span dir=LTR></span>A hook point for an ACL to decide what to do in such a scenario ie in case of an error in the negotiation with the server<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I have seen Golang code that does something about it and it works based on the assumption that the client will always send something before the server.<o:p></o:p></p><p class=MsoNormal>The sketch of such a function can be like the PROXY protocol parsing(in a way…).<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span dir=LTR></span>If TLS handshake exists, try to parse<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span dir=LTR></span>If parse is OK try to connect the remote server else throw the connection into some ACL<o:p></o:p></p><p class=MsoListParagraph style='text-indent:-.25in;mso-list:l0 level1 lfo1'><![if !supportLists]><span style='mso-list:Ignore'>-<span style='font:7.0pt "Times New Roman"'> </span></span><![endif]><span dir=LTR></span>If the remote server responds well to a TLS handshare, bump else spice<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I understand that it overlaps some of the bump-first in a way.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>With this issue the resolution for other scenarios: which a client really doesn’t speak RFC TLS or something similar, might be possible?<o:p></o:p></p><p class=MsoNormal>I have seen couple times a situation which port 443 is used for customized protocols such as VPN and others.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>The risk I can see is that the proxy admins (which we know that do weird stuff when allowed) will allow any TLS error to be bypassed.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>If we will leave the error logs into cache.log in debug level 1 like today but still allow to bypass, would it change anything?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I will really appreciate feedback about this specific issue.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Eliezer<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>----<o:p></o:p></p><p class=MsoNormal>Eliezer Croitoru<o:p></o:p></p><p class=MsoNormal>Tech Support<o:p></o:p></p><p class=MsoNormal>Mobile: +972-5-28704261<o:p></o:p></p><p class=MsoNormal>Email: <a href="mailto:ngtech1ltd@gmail.com"><span style='color:blue'>ngtech1ltd@gmail.com</span></a><o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p></div></body></html>