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    SubjectRe: [PATCH] fix small DoS on connect() (was Re: BUG: Unusual TCP Connect() results.)
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    On Sun, Jun 12, 2005 at 02:32:53PM +0200, Willy Tarreau wrote:
    >
    > but it's not the case (although the naming is not clear). So if the remote
    > end was the one which sent the SYN-ACK, it will clear its session. If it has
    > been spoofed, it will ignore the RST because in turn, the SEQ will not be
    > within its window.

    This is what should happen:

    1) client A sends SYN to server B.
    2) attcker C sends spoofed SYN-ACK to client A purporting to be server B.
    3) client A sends RST to server B.

    The RST packet is sent by client A using its sequence numbers. Therefore
    it will pass the sequence number check on server B.

    4) server B resets the connection.

    Cheers,
    --
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