ng_pipe: Do not panic when memory allocations fail

Signed-off-by: Martin Vahlensieck <git@academicsolutions.ch>

Reviewed by: markj
MFC after: 2 weeks
Pull Request: https://github.com/freebsd/freebsd-src/pull/1181

ng_pipe: Replace deprecated random() with prng32_bounded()

Signed-off-by: Martin Vahlensieck <git@academicsolutions.ch>

MFC after: 2 weeks
Reviewed by: markj
Pull Request: https://github.com/freebsd/freebsd-src/pull/1181

ng_pipe: Remove node when all hooks are disconnected

This is the behavior described in the man page.

Signed-off-by: Martin Vahlensieck <git@academicsolutions.ch>

Discussed with: glebius
Reviewed by: markj
MFC after: 2 weeks
Pull Request: https://github.com/freebsd/freebsd-src/pull/1181

ng_pipe: Fix whitespace

Signed-off-by: Martin Vahlensieck <git@academicsolutions.ch>

Reviewed by: markj
MFC after: 2 weeks
Pull Request: https://github.com/freebsd/freebsd-src/pull/1181

sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

net: clean up empty lines in .c and .h files

sys: general adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

No functional change intended.

Use M_WAITOK for the NGM_PIPE_SET_CFG control message. We expect it to
arrive from userland only.

Submitted by: Dmitry Luhtionov <dmitryluhtionov gmail.com>

Eliminate duplicated & dead code.

MFC after: 3 days

Assume the link to be dead if bit error rate (BER) parameter is set to 1.
When a transition from link alive to link dead configuration or vice
versa occurs, notify any upstream and / or downstream peers using
NGM_FLOW messagges.

Link state notification using NGM_FLOW messages is modelled around
around already existing code in ng_ether.c.

MFC after: 3 days

Node constructor methods are supposed to be called in syscall
context always. Convert nodes to consistently use M_WAITOK flag
for memory allocation.

Reviewed by: julian

Simplify ng_pipe locking model by relying on the netgraph framework
to provide serialization of calls into the node, which is accomplished
by markng the node as single-threaded (NGF_FORCE_WRITER).

The price we pay is that each ng_pipe instance now has its own callout
handler which polls for queued frames on each clock tick, as long as
the pipe has any frames in its internal queues. OTOH, we got rid of
the global ng_pipe mutex, so from now on multiple ng_pipe instances
can operate in parallel. This change also fixes counting of forwarded
frames when an ng_pipe node is not enforcing any packet impairments.

While here, attempt to improve adherance to style(9) throughout
otherwise mostly unreadable code.

MFC after: 3 days

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Fix a double-free bug which can occur if both bit error rate and packet
duplication probability are configured on a ng_pipe node.

Submitted by: Jeffrey Ahrenholtz
MFC after: 3 days

Avoid undefined behaviour.

Reviewed by: zec@

Start copyright notice with /*-

Merge the remainder of kern_vimage.c and vimage.h into vnet.c and
vnet.h, we now use jails (rather than vimages) as the abstraction
for virtualization management, and what remained was specific to
virtual network stacks. Minor cleanups are done in the process,
and comments updated to reflect these changes.

Reviewed by: bz
Approved by: re (vimage blanket)

Retire the MALLOC and FREE macros. They are an abomination unto style(9).

MFC after: 3 months

- Import the HEAD csup code which is the basis for the cvsmode work.

Add Marko's pipe node.
This allows one to do flow modulation similar to dummynet
between arbitrary nodes.