Add kernel-side support for in-kernel TLS.

KTLS adds support for in-kernel framing and encryption of Transport
Layer Security (1.0-1.2) data on TCP sockets. KTLS only supports
offload of TLS for tr

Add kernel-side support for in-kernel TLS.

KTLS adds support for in-kernel framing and encryption of Transport
Layer Security (1.0-1.2) data on TCP sockets. KTLS only supports
offload of TLS for transmitted data. Key negotation must still be
performed in userland. Once completed, transmit session keys for a
connection are provided to the kernel via a new TCP_TXTLS_ENABLE
socket option. All subsequent data transmitted on the socket is
placed into TLS frames and encrypted using the supplied keys.

Any data written to a KTLS-enabled socket via write(2), aio_write(2),
or sendfile(2) is assumed to be application data and is encoded in TLS
frames with an application data type. Individual records can be sent
with a custom type (e.g. handshake messages) via sendmsg(2) with a new
control message (TLS_SET_RECORD_TYPE) specifying the record type.

At present, rekeying is not supported though the in-kernel framework
should support rekeying.

KTLS makes use of the recently added unmapped mbufs to store TLS
frames in the socket buffer. Each TLS frame is described by a single
ext_pgs mbuf. The ext_pgs structure contains the header of the TLS
record (and trailer for encrypted records) as well as references to
the associated TLS session.

KTLS supports two primary methods of encrypting TLS frames: software
TLS and ifnet TLS.

Software TLS marks mbufs holding socket data as not ready via
M_NOTREADY similar to sendfile(2) when TLS framing information is
added to an unmapped mbuf in ktls_frame(). ktls_enqueue() is then
called to schedule TLS frames for encryption. In the case of
sendfile_iodone() calls ktls_enqueue() instead of pru_ready() leaving
the mbufs marked M_NOTREADY until encryption is completed. For other
writes (vn_sendfile when pages are available, write(2), etc.), the
PRUS_NOTREADY is set when invoking pru_send() along with invoking
ktls_enqueue().

A pool of worker threads (the "KTLS" kernel process) encrypts TLS
frames queued via ktls_enqueue(). Each TLS frame is temporarily
mapped using the direct map and passed to a software encryption
backend to perform the actual encryption.

(Note: The use of PHYS_TO_DMAP could be replaced with sf_bufs if
someone wished to make this work on architectures without a direct
map.)

KTLS supports pluggable software encryption backends. Internally,
Netflix uses proprietary pure-software backends. This commit includes
a simple backend in a new ktls_ocf.ko module that uses the kernel's
OpenCrypto framework to provide AES-GCM encryption of TLS frames. As
a result, software TLS is now a bit of a misnomer as it can make use
of hardware crypto accelerators.

Once software encryption has finished, the TLS frame mbufs are marked
ready via pru_ready(). At this point, the encrypted data appears as
regular payload to the TCP stack stored in unmapped mbufs.

ifnet TLS permits a NIC to offload the TLS encryption and TCP
segmentation. In this mode, a new send tag type (IF_SND_TAG_TYPE_TLS)
is allocated on the interface a socket is routed over and associated
with a TLS session. TLS records for a TLS session using ifnet TLS are
not marked M_NOTREADY but are passed down the stack unencrypted. The
ip_output_send() and ip6_output_send() helper functions that apply
send tags to outbound IP packets verify that the send tag of the TLS
record matches the outbound interface. If so, the packet is tagged
with the TLS send tag and sent to the interface. The NIC device
driver must recognize packets with the TLS send tag and schedule them
for TLS encryption and TCP segmentation. If the the outbound
interface does not match the interface in the TLS send tag, the packet
is dropped. In addition, a task is scheduled to refresh the TLS send
tag for the TLS session. If a new TLS send tag cannot be allocated,
the connection is dropped. If a new TLS send tag is allocated,
however, subsequent packets will be tagged with the correct TLS send
tag. (This latter case has been tested by configuring both ports of a
Chelsio T6 in a lagg and failing over from one port to another. As
the connections migrated to the new port, new TLS send tags were
allocated for the new port and connections resumed without being
dropped.)

ifnet TLS can be enabled and disabled on supported network interfaces
via new '[-]txtls[46]' options to ifconfig(8). ifnet TLS is supported
across both vlan devices and lagg interfaces using failover, lacp with
flowid enabled, or lacp with flowid enabled.

Applications may request the current KTLS mode of a connection via a
new TCP_TXTLS_MODE socket option. They can also use this socket
option to toggle between software and ifnet TLS modes.

In addition, a testing tool is available in tools/tools/switch_tls.
This is modeled on tcpdrop and uses similar syntax. However, instead
of dropping connections, -s is used to force KTLS connections to
switch to software TLS and -i is used to switch to ifnet TLS.

Various sysctls and counters are available under the kern.ipc.tls
sysctl node. The kern.ipc.tls.enable node must be set to true to
enable KTLS (it is off by default). The use of unmapped mbufs must
also be enabled via kern.ipc.mb_use_ext_pgs to enable KTLS.

KTLS is enabled via the KERN_TLS kernel option.

This patch is the culmination of years of work by several folks
including Scott Long and Randall Stewart for the original design and
implementation; Drew Gallatin for several optimizations including the
use of ext_pgs mbufs, the M_NOTREADY mechanism for TLS records
awaiting software encryption, and pluggable software crypto backends;
and John Baldwin for modifications to support hardware TLS offload.

Reviewed by: gallatin, hselasky, rrs
Obtained from: Netflix
Sponsored by: Netflix, Chelsio Communications
Differential Revision: https://reviews.freebsd.org/D21277

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MFHead @r350386

Sponsored by: The FreeBSD Foundation

This commit updates rack to what is basically being used at NF as
well as sets in some of the groundwork for committing BBR. The
hpts system is updated as well as some other needed utilities
for the

This commit updates rack to what is basically being used at NF as
well as sets in some of the groundwork for committing BBR. The
hpts system is updated as well as some other needed utilities
for the entrance of BBR. This is actually part 1 of 3 more
needed commits which will finally complete with BBRv1 being
added as a new tcp stack.

Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D20834

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This commit brings in a new refactored TCP stack called Rack.
Rack includes the following features:
- A different SACK processing scheme (the old sack structures are not used).
- RACK (Recent ackno

This commit brings in a new refactored TCP stack called Rack.
Rack includes the following features:
- A different SACK processing scheme (the old sack structures are not used).
- RACK (Recent acknowledgment) where counting dup-acks is no longer done
instead time is used to knwo when to retransmit. (see the I-D)
- TLP (Tail Loss Probe) where we will probe for tail-losses to attempt
to try not to take a retransmit time-out. (see the I-D)
- Burst mitigation using TCPHTPS
- PRR (partial rate reduction) see the RFC.

Once built into your kernel, you can select this stack by either
socket option with the name of the stack is "rack" or by setting
the global sysctl so the default is rack.

Note that any connection that does not support SACK will be kicked
back to the "default" base FreeBSD stack (currently known as "default").

To build this into your kernel you will need to enable in your
kernel:
makeoptions WITH_EXTRA_TCP_STACKS=1
options TCPHPTS

Sponsored by: Netflix Inc.
Differential Revision: https://reviews.freebsd.org/D15525

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Add the "TCP Blackbox Recorder" which we discussed at the developer
summits at BSDCan and BSDCam in 2017.

The TCP Blackbox Recorder allows you to capture events on a TCP connection
in a ring buffer.

Add the "TCP Blackbox Recorder" which we discussed at the developer
summits at BSDCan and BSDCam in 2017.

The TCP Blackbox Recorder allows you to capture events on a TCP connection
in a ring buffer. It stores metadata with the event. It optionally stores
the TCP header associated with an event (if the event is associated with a
packet) and also optionally stores information on the sockets.

It supports setting a log ID on a TCP connection and using this to correlate
multiple connections that share a common log ID.

You can log connections in different modes. If you are doing a coordinated
test with a particular connection, you may tell the system to put it in
mode 4 (continuous dump). Or, if you just want to monitor for errors, you
can put it in mode 1 (ring buffer) and dump all the ring buffers associated
with the connection ID when we receive an error signal for that connection
ID. You can set a default mode that will be applied to a particular ratio
of incoming connections. You can also manually set a mode using a socket
option.

This commit includes only basic probes. rrs@ has added quite an abundance
of probes in his TCP development work. He plans to commit those soon.

There are user-space programs which we plan to commit as ports. These read
the data from the log device and output pcapng files, and then let you
analyze the data (and metadata) in the pcapng files.

Reviewed by: gnn (previous version)
Obtained from: Netflix, Inc.
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D11085

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This is an implementation of the client side of TCP Fast Open (TFO)
[RFC7413]. It also includes a pre-shared key mode of operation in
which the server requires the client to be in possession of a sha

This is an implementation of the client side of TCP Fast Open (TFO)
[RFC7413]. It also includes a pre-shared key mode of operation in
which the server requires the client to be in possession of a shared
secret in order to successfully open TFO connections with that server.

The names of some existing fastopen sysctls have changed (e.g.,
net.inet.tcp.fastopen.enabled -> net.inet.tcp.fastopen.server_enable).

Reviewed by: tuexen
MFC after: 1 month
Sponsored by: Limelight Networks
Differential Revision: https://reviews.freebsd.org/D14047

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Merge ^/head r325999 through r326131.

sys: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for

sys: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 3-Clause license.

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.

Special thanks to Wind River for providing access to "The Duke of
Highlander" tool: an older (2014) run over FreeBSD tree was useful as a
starting point.

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Merge ^/head r314420 through r314481.

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is

Renumber copyright clause 4

Renumber cluase 4 to 3, per what everybody else did when BSD granted
them permission to remove clause 3. My insistance on keeping the same
numbering for legal reasons is too pedantic, so give up on that point.

Submitted by: Jan Schaumann <jschauma@stevens.edu>
Pull Request: https://github.com/freebsd/freebsd/pull/96

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MFH

Sponsored by: The FreeBSD Foundation

Merge ^/head r294169 through r294598.

MFH @r294567

Provide new socket option TCP_CCALGOOPT, which stands for TCP congestion
control algorithm options. The argument is variable length and is opaque
to TCP, forwarded directly to the algorithm's ctl_ou

Provide new socket option TCP_CCALGOOPT, which stands for TCP congestion
control algorithm options. The argument is variable length and is opaque
to TCP, forwarded directly to the algorithm's ctl_output method.

Provide new includes directory netinet/cc, where algorithm specific
headers can be installed.

The new API doesn't yet have any in tree consumers.

The original code written by lstewart.
Reviewed by: rrs, emax
Sponsored by: Netflix
Differential Revision: https://reviews.freebsd.org/D711

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MFH r289384-r293170

Sponsored by: The FreeBSD Foundation

Mfh r292839

Implementation of server-side TCP Fast Open (TFO) [RFC7413].

TFO is disabled by default in the kernel build. See the top comment
in sys/netinet/tcp_fastopen.c for implementation particulars.

Revie

Implementation of server-side TCP Fast Open (TFO) [RFC7413].

TFO is disabled by default in the kernel build. See the top comment
in sys/netinet/tcp_fastopen.c for implementation particulars.

Reviewed by: gnn, jch, stas
MFC after: 3 days
Sponsored by: Verisign, Inc.
Differential Revision: https://reviews.freebsd.org/D4350

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MFH @r292599

This includes the pluggable TCP framework and other chnages to the
netstack to track for VNET stability.

Security: The FreeBSD Foundation

First cut of the modularization of our TCP stack. Still
to do is to clean up the timer handling using the async-drain.
Other optimizations may be coming to go with this. Whats here
will allow differn

First cut of the modularization of our TCP stack. Still
to do is to clean up the timer handling using the async-drain.
Other optimizations may be coming to go with this. Whats here
will allow differnet tcp implementations (one included).
Reviewed by: jtl, hiren, transports
Sponsored by: Netflix Inc.
Differential Revision: D4055

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Catch up with head (r291075).

Merge from head

Sponsored by: Gandi.net

Merge from head

MFH to r289370

Sponsored by: The FreeBSD Foundation

There are times when it would be really nice to have a record of the last few
packets and/or state transitions from each TCP socket. That would help with
narrowing down certain problems we see in the

There are times when it would be really nice to have a record of the last few
packets and/or state transitions from each TCP socket. That would help with
narrowing down certain problems we see in the field that are hard to reproduce
without understanding the history of how we got into a certain state. This
change provides just that.

It saves copies of the last N packets in a list in the tcpcb. When the tcpcb is
destroyed, the list is freed. I thought this was likely to be more
performance-friendly than saving copies of the tcpcb. Plus, with the packets,
you should be able to reverse-engineer what happened to the tcpcb.

To enable the feature, you will need to compile a kernel with the TCPPCAP
option. Even then, the feature defaults to being deactivated. You can activate
it by setting a positive value for the number of captured packets. You can do
that on either a global basis or on a per-socket basis (via a setsockopt call).

There is no way to get the packets out of the kernel other than using kmem or
getting a coredump. I thought that would help some of the legal/privacy concerns
regarding such a feature. However, it should be possible to add a future effort
to export them in PCAP format.

I tested this at low scale, and found that there were no mbuf leaks and the peak
mbuf usage appeared to be unchanged with and without the feature.

The main performance concern I can envision is the number of mbufs that would be
used on systems with a large number of sockets. If you save five packets per
direction per socket and have 3,000 sockets, that will consume at least 30,000
mbufs just to keep these packets. I tried to reduce the concerns associated with
this by limiting the number of clusters (not mbufs) that could be used for this
feature. Again, in my testing, that appears to work correctly.

Differential Revision: D3100
Submitted by: Jonathan Looney <jlooney at juniper dot net>
Reviewed by: gnn, hiren

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Merge fresh head.