Re: SEPT, Was: IBM supplied QPGMR

["Leif Svalgaard" <leif@xxxxxxxx>]

From: jt <jt@ee.net>
> The SEPT is the System Entry Point Table.  It is an array of pointers to
the
> storage location of different system programs.  It's used in MI
programming.

and all the other HLLs (except java?). Every RPG programs contains
several SEPT calls.

> BTW, easiest way I can think of to crater a system is to hook the SEPT.
> Move a pointer to one of your programs into the SEPT array.  I wouldn't
know
> how to go about it, but am sure the MI-list does.

With V5R1, destroying the SEPT has become more difficult.

>
> I dunno about security checking.  IIRCAIMN (and I may not) the security is
> built into the pointer.
>

The SEPT is not really a security exposure. On the contrary, using the
SEPT prevents you from inserting your own programs earlier in the
library list to masquerade as a system program.