libiptc and adding a simple SNAT rule

[shaun <shaun@newfind.net>]

Hello -

I'm building an app that will dynamically modify rules in the POSTROUTING chain
in the nat table (SNAT).  I can iterate through the list and remove chain
entries ok so far, and I have some example code that successfully appends a
'blank' rule to the chain.  

But when I try to iptc_append_entry a simple but specific rule I've created in
my app to the chain, I get an error on the iptc_commit.  

In my app, I can compare (what should be) an identical rule as created by
running /sbin/iptables vs. the struct ipt_entry I'm trying to append and the
only difference I see is a difference in the target offset size.  Evidently,
I'm supposed to add some data to the end of the struct ipt_entry.

So my question:  What am I supposed to tack on to the end of the struct
ipt_entry when constructing and appending a non multi-range SNAT rule?

Thanks.

-- 
Shaun McIntyre
shaun@newfind.net
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