netgraph/ng_vlan_rotate: IEEE 802.1ad VLAN manipulation netgraph node type (new type)

[donner]

Summary

This node is part of an A10-NSP development.

Carrier networks tend to stack three or more tags for internal purposes and therefore hiding the service tags deep inside of the stack. When decomposing such an access network frame, the processing order is typically reversed: First distinguish by service, than by other means.

This new netgragh node allows to bring the relevant VLAN in front (to the out-most position). This way other netgraph nodes (like ng_vlan) can operate on this specific type.

Test Plan

The example section of the man page contains two examples, how to use this node.
It also contains the sniffer insight of the manipulation process.

[kevans]

sys/netgraph/ng_vlan_rotate.c

473

Operator belongs to the line before it, with the wrapping starting just after.

[donner]

Run indent(1) on the source files.
Reduced comments from the boilerplate.
Changed hard coded ethertypes by global definitions introduced by D21846.

[donner]

Rebase to r357812

[donner]

rebase to r358008.

[donner]

Updated to revision 358170.

[donner]

Updated to revision 358500.

[donner]

We are going to hard production now.
Any interest in reviewing it?

[donner]

@brueffer Are your concerns resolved?

[donner]

Rebase to r366170.

[gbe]

LGTM

[donner]

Updated to revision 367040.

[gbe]

LGTM.

share/man/man4/ng_vlan_rotate.4

3

The "All rights reserved." should be dropped.

sys/netgraph/ng_vlan_rotate.c

6

The "All rights reserved." should be dropped.

sys/netgraph/ng_vlan_rotate.h

6

The "All rights reserved." should be dropped.

[afedorov]

share/man/man4/ng_vlan_rotate.4

3

While we're here, maybe it should be added: "SPDX-License-Identifier: BSD-2-Clause-FreeBSD"

[donner]

Updated to latest revision and fixed copyright annotations.

[donner]

Mark annotations as done.

[donner]

Updated to revision 368146.

[donner]

Updated to revision 368820.

[kp]

Couple really minor (and mostly style(9) remarks, other than those I think it's good.

sys/modules/netgraph/vlan_rotate/Makefile

2

This tag is no longer required in the git world.
If you're planning to MFC this to stable/12 it may be useful to just leave it, because it does still do something in svn.

sys/netgraph/ng_vlan_rotate.c

30

Same.

166

This line is (just) too long.

193

Or maybe just 'else' in the above if/else cascade?

238

Line length.

373

Line length.

425

Are netgraph nodes implicitly locked?
If not, this could potentially miscount if two cores run the function at the same time. Not a huge issue, but perhaps counter(9) would be useful here.

sys/netgraph/ng_vlan_rotate.h

30

Same.

[donner]

• Converted from subversion
• Switch to counter framework for statistics
• Fix style(9) errors
• Bump dates

[donner]

• Fix spelling error.

[donner]

sys/modules/netgraph/vlan_rotate/Makefile

2

So I'll leave it.

sys/netgraph/ng_vlan_rotate.c

425

They are not locked automatically (which is good).
So you are right, I've to switch to the counter framework.

[kp]

Approved by: kp (mentor)

[donner]

@brueffer are your concerns still relevant?

[brueffer]

Just two small comments, looks good otherwise.

share/man/man4/ng_vlan_rotate.4

71

Stray comma after stack.

254

This can simply be .Nm

[donner]

• Fix man page nits.

[brueffer]

share/man/man4/ng_vlan_rotate.4

254

You fixed a different .Nm than the one I pointed out ;-) This one in HISTORY can be simply .Nm as well.

[donner]

• Fix man page nits.
• Removed false history from man page.

[kp]

Approved by: kp (mentor)