review for outgoing TCP port reuse

[Mike Karels]

Richard has now approved this review, but transport is still blocking.
Can someone do a review for transport?  The change is not that extensive.

btw, Phabricator shows a lint/build error, but that is spurious.  Lint
thinks that the existing variable "nam" is mis-spelled, and I changed a
line that referred to it.  I don't know why we are spell-checking code.

Thanks,
		Mike

> To: transport at freebsd.org
> From: Mike Karels <karels at freebsd.org>
> Subject: Re: review for outgoing TCP port reuse
> Date: Wed, 13 May 2020 06:46:09 -0500

> I created the following review over the weekend.  I have still not received
> any review comments other than a question.  Anyone have time to review this?

> Thanks,
> 		Mike

> > To: transport at freebsd.org
> > From: Mike Karels <karels at FreeBSD.org>
> > Subject: review for outgoing TCP port reuse
> > Date: Sat, 09 May 2020 10:44:52 -0500

> > I just created a review with the following description:

> > Allow TCP to reuse local port with different destinations

> > Summary:
> > Previously, tcp_connect() would bind a local port before connecting,
> > forcing the local port to be unique across all outgoing TCP connections 
> > for the address family.  Instead, choose a local port after selecting 
> > the destination and the local address, requiring only that the tuple 
> > is unique.

> > The review is https://reviews.freebsd.org/D24781.

> > The change originated on the Sidewinder firewall, which is proxy-based as
> > well as packet-filter based, and needed to support more proxy connections
> > than the pool of ephemeral ports as long as the destinations were different.

> > 		Mike