TCP packet sequence numbering

[Bob Carback]

Used to be able to use nettune to enable TCP packet sequence numbering with --
nettune -s tcp_random_seq 2

Is there an equivelent for ndd?

[Carlos Roberto Schimidt]

Hi Bob,

I think this document may help you:

ftp://ftp.cup.hp.com/dist/networking/briefs/annotated_ndd.txt

Behavior is a little different in HP 11.x

SChimidt

[Bob Carback]

Thanks. This doesn't appear to mention random TCP packet sequence numbering. Any idea for another name for this?

[James A. Donovan · Accepted solution]

Depends on which OS you're now using....

To enable tcp randomization on HP-UX 11.00, 11.04, and 11.11(11i):

----------------------------------------------------------------------
--

HP randomization

HP-UX release 11.00:
Install PHNE_22397 or subsequent. The HP randomization will
then be the default tcp randomization.

NOTE: This patch has dependencies.


HP-UX release 11.11 (11i):
No patch is required. The HP randomization has always been
implemented in HP-UX 11.11 (11i) and is the default tcp
randomization.

RFC 1948 ISN randomization

HP-UX 11.00: Apply PHNE_26771 or subsequent.
HP-UX 11.04: Apply PHNE_26101 or subsequent.
HP-UX 11.11 (11i): Apply PHNE_25644 or subsequent.

Once the appropriate patch has been applied the RFC 1948 ISN
randomization can be enabled on HP-UX 11.00, 11.04 and 11.11
by executing the following command as root:

ndd -set /dev/tcp tcp_isn_passphrase
where is any length character
string. Only the first 32 characters will be
retained. If the passphrase is changed the system
should be rebooted.

NOTE: RFC 1948 ISN randomization is not available on
HP-UX release 10.20. Customers who want RFC 1948
ISN randomization should upgrade to HP-UX 11.X and
apply necessary patches as discussed herein.

[Bob Carback]

This is actually HP-UX 11.23 (11iv2 ia64)

[rick jones]

I really should update that annotated_ndd document one of these days...