<div dir="ltr"><div dir="ltr">Thanks Ben,<br>I will look into it.<br><br>Is there any custom implementation of the application-level header processing (not necessary HTTP)? </div><div dir="ltr">Any tutorial talking about any application-layer header parsing/ processing would help me get started.</div><div dir="ltr"><div><br><br><div id="mt-signature">
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                    <span style="color:transparent;font-size:0">05/05/20, 05:00:35 PM</span>
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    </div></div></div><br><div class="gmail_quote"><div dir="ltr" class="gmail_attr">On Tue, May 5, 2020 at 4:54 PM Lewis, Ben <<a href="mailto:b.lewis@lancaster.ac.uk">b.lewis@lancaster.ac.uk</a>> wrote:<br></div><blockquote class="gmail_quote" style="margin:0px 0px 0px 0.8ex;border-left:1px solid rgb(204,204,204);padding-left:1ex">





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<p class="MsoNormal"><span>As I understand it, P4 does not well suit variable length header processing, such as those present in HTTP.
<u></u><u></u></span></p>
<p class="MsoNormal"><span><u></u> <u></u></span></p>
<p class="MsoNormal"><span>Andy Fingerhut talks about some of the challenges in P4 with variable length headers here:
<a href="https://github.com/jafingerhut/p4-guide/tree/master/variable-length-header" target="_blank">
https://github.com/jafingerhut/p4-guide/tree/master/variable-length-header</a><u></u><u></u></span></p>
<p class="MsoNormal"><span><u></u> <u></u></span></p>
<p class="MsoNormal"><span>Regards<u></u><u></u></span></p>
<p class="MsoNormal"><span>Ben<u></u><u></u></span></p>
<p class="MsoNormal"><span><u></u> <u></u></span></p>
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<p class="MsoNormal"><b><span style="font-size:12pt;color:black">From: </span></b><span style="font-size:12pt;color:black">P4-dev <<a href="mailto:p4-dev-bounces@lists.p4.org" target="_blank">p4-dev-bounces@lists.p4.org</a>> on behalf of Sahil Gupta <<a href="mailto:sg5414@rit.edu" target="_blank">sg5414@rit.edu</a>><br>
<b>Reply to: </b>"<a href="mailto:sg5414@rit.edu" target="_blank">sg5414@rit.edu</a>" <<a href="mailto:sg5414@rit.edu" target="_blank">sg5414@rit.edu</a>><br>
<b>Date: </b>Tuesday, 5 May 2020 at 21:45<br>
<b>To: </b>p4-dev <<a href="mailto:p4-dev@lists.p4.org" target="_blank">p4-dev@lists.p4.org</a>><br>
<b>Subject: </b>[External] [P4-dev] Any code for http header processing<u></u><u></u></span></p>
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<p class="MsoNormal"><u></u> <u></u></p>
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<p><strong><span style="font-family:Calibri,sans-serif;color:rgb(164,52,58)">This email originated outside the University. Check before clicking links or attachments.</span></strong><u></u><u></u></p>
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<p class="MsoNormal">Hi all,<br>
1. Is there any p4 code available in which HTTP header is parsed and some comparison is done on its field. 
<u></u><u></u></p>
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<p class="MsoNormal" style="margin-bottom:12pt">2. Also, looking for projects where some sort of FSM is implemented in match-action stages?<br>
Any help is appreciated.<u></u><u></u></p>
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<p class="MsoNormal">Thanks<u></u><u></u></p>
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<p class="MsoNormal" style="margin-bottom:12pt">Sahil Gupta<br>
<br>
<u></u><u></u></p>
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<span style="font-size:1pt">05/05/20, 04:37:28 PM</span> <u></u><u></u></p>
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