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Re: ping.
On Wed, 9 Jun 1999, Can Altineller wrote:
> However in OpenBSD the identifier field is different every time
> that a ICMP_ECHO_REQUEST|REPLY is sent. In FreeBSD it is not the same, but
> it is sequential. (increases by one)
this is because OpenBSD allocates pid's (and unreserved ports, etc.)
randomly. this fixes a slew of attacks in protocols that rely on
predictable information for sequencing (e.g. RPC xid's, etc.).
-d.
---
http://www.monkey.org/~dugsong/
- References:
- ping.
- From: Can Altineller <altine@yacht.ee.fit.edu>