openssh-2.9p2, short hostnames

Nicolas Williams Nicolas.Williams at
Wed Oct 3 02:20:24 EST 2001

On Tue, Oct 02, 2001 at 06:16:07PM +0200, Hans Werner Strube wrote:
> > > While the length of a key's value is 1024 bytes, you can break the
> > > value so it references other *keys* and therefore work around this
> > > limitation. If you generate the NDBM maps directly from text files
> > > though, your kinda screwed unless you somehow automate this process.
> I have already applied this technique before (even for too many short
> host names) but would like to avoid it if possible.

Automate this. It's not hard. Remember, split the netgroups into a
shallow tree of netgroups, not a deep list. Some broken innetgr()
implementations do a depth-first traversal with a depth-limit as an
anti-looping heuristic.

> > The reverse maps are the ones used by innetgr() on Solaris. The reverse
> > maps' keys are named after users and hosts, and the values are
> > comma-separated lists of netgroups the users/hosts belong to.
> > 
> > There's no way to break those up.
> But there is no need to break those up, since those records are quite short.

The hostname being long does not much affect the reverse map entries.
That is true.

But I have certainly seen very, very long reverse map entries.

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