If the initial sequence number of the other side could be predicted, blind tcp initial and inject(use a source ip address that not alive)may be possible.
See, now you've gone and set off my spidey sense again. Here you are, supporting my argument that you're up to no good with this code.

If thre's a legitimate use for this code, would you please explain it?

-- Randal L. Schwartz, Perl hacker
Be sure to read my standard disclaimer if this is a reply.

In reply to Re^4: Insert the 4th TCP packet after TCP three-times handshakes by merlyn
in thread Insert the 4th TCP packet after TCP three-times handshakes by shanleiguang

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