Add random source/destination address generation to pkt-gen.

[adrian]

Summary

It's hard to test hash distribution testing when pkt-gen only walks
IP ranges. This adds IPv4 source/destination randomization.

[hiren]

There seem to be a bunch of whitespace changes. Other than that, looks good to me.

Try to run this by luigi as he maintains this code upstream also.

tools/tools/netmap/pkt-gen.c

584

Are these all whitespace changes or something funky that phabricator is doing?

[gnn]

Do it.

[emaste]

Is this going to be committed?

[imp]

Appears to have landed, didn't close. Assuming we're done.

commit 56717743f2320dd8a13bdcc4f8decddbf1703bd1
Author: Adrian Chadd <[e-mail]>
Date: Sun Apr 19 17:07:51 2015 +0000

Update pkt-gen to optionally use randomised source/destination
IPv4 addresses/ports.

When doing traffic testing of actual code that /does/ things to the
packet (rather than say, 'bridge.c'), it's typically a good idea to
use a variety of cache-busting and flow-tracking-busting packet
spreads.  The pkt-gen method of testing an IP range was to walk
it linearly - which is fine, but not useful enough.

This can be used to completely randomize the source/destination
addresses (eg to test out flow-tracking-busting) and to keep the
destination fixed whilst randomising the source (eg to test out
what a DDoS may look like.)

Tested:

* Intel ixgbe 10G (82599) netmap

Differential Revision:  https://reviews.freebsd.org/D2309
MFC after:      2 weeks
Sponsored by:   Norse Corp, Inc.

Notes:

svn path=/head/; revision=281746