Writing an http sniffer (or any other application level sniffer)

Posted by Ishi on Stack Overflow See other posts from Stack Overflow or by Ishi
Published on 2010-05-25T14:11:32Z Indexed on 2010/05/26 5:31 UTC
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pcap

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sniffer

Dear all, I am trying my hands understanding PCAP libraries. I am able to apply a filter and get the TCP payload at port 80. But what next ? How can I read the HTTP data - suppose I want to know the "User Agent" field value in the http header..how should I proceed ? I have searched the website (and googled a lot too), and could find a related thread here : http://stackoverflow.com/questions/2073183/writing-a-http-sniffer. But this doesn't help me anywhere...

Thanks !!

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