The implementation is similar to linux where we track the number of bytes
consumed by the application to grow the receive buffer of a given TCP endpoint.
This ensures that the advertised window grows at a reasonable rate to accomodate
for the sender's rate and prevents large amounts of data being held in stack
buffers if the application is not actively reading or not reading fast enough.
The original paper that was used to implement the linux receive buffer auto-
tuning is available @ https://public.lanl.gov/radiant/pubs/drs/lacsi2001.pdf
NOTE: Linux does not implement DRS as defined in that paper, it's just a good
reference to understand the solution space.
Updates #230
PiperOrigin-RevId: 253168283
This CL also cleans up the error returned for setting congestion
control which was incorrectly returning EINVAL instead of ENOENT.
PiperOrigin-RevId: 252889093
Changes netstack to confirm to current linux behaviour where if the backlog is
full then we drop the SYN and do not send a SYN-ACK. Similarly we allow upto
backlog connections to be in SYN-RCVD state as long as the backlog is not full.
We also now drop a SYN if syn cookies are in use and the backlog for the
listening endpoint is full.
Added new tests to confirm the behaviour.
Also reverted the change to increase the backlog in TcpPortReuseMultiThread
syscall test.
Fixes#236
PiperOrigin-RevId: 252500462
This is necessary for implementing network diagnostic interfaces like
/proc/net/{tcp,udp,unix} and sock_diag(7).
For pass-through endpoints such as hostinet, we obtain the socket
state from the backend. For netstack, we add explicit tracking of TCP
states.
PiperOrigin-RevId: 251934850
This allows an fdbased endpoint to have multiple underlying fd's from which
packets can be read and dispatched/written to.
This should allow for higher throughput as well as better scalability of the
network stack as number of connections increases.
Updates #231
PiperOrigin-RevId: 251852825
In case of GSO, a segment can container more than one packet
and we need to use the pCount() helper to get a number of packets.
PiperOrigin-RevId: 251743020
Multicast packets are special in that their destination address does not
identify a specific interface. When sending out such a packet the multicast
address is the remote address, but for incoming packets it is the local
address. Hence, when looping a multicast packet, the route needs to be
tweaked to reflect this.
PiperOrigin-RevId: 251739298
When checking the length of the acceptedChan we should hold the
endpoint mutex otherwise a syn received while the listening socket
is being closed can result in a data race where the cleanupLocked
routine sets acceptedChan to nil while a handshake goroutine
in progress could try and check it at the same time.
PiperOrigin-RevId: 251537697
Netstack sets the unprocessed segment queue size to match the receive
buffer size. This is not required as this queue only needs to hold enough
for a short duration before the endpoint goroutine can process it.
Updates #230
PiperOrigin-RevId: 250976323
Funcion signatures are not validated during compilation. Since
they are not exported, they can change at any time. The guard
ensures that they are verified at least on every version upgrade.
PiperOrigin-RevId: 250733742
Netstack listen loop can get stuck if cookies are in-use and the app is slow to
accept incoming connections. Further we continue to complete handshake for a
connection even if the backlog is full. This creates a problem when a lots of
connections come in rapidly and we end up with lots of completed connections
just hanging around to be delivered.
These fixes change netstack behaviour to mirror what linux does as described
here in the following article
http://veithen.io/2014/01/01/how-tcp-backlog-works-in-linux.html
Now when cookies are not in-use Netstack will silently drop the ACK to a SYN-ACK
and not complete the handshake if the backlog is full. This will result in the
connection staying in a half-complete state. Eventually the sender will
retransmit the ACK and if backlog has space we will transition to a connected
state and deliver the endpoint.
Similarly when cookies are in use we do not try and create an endpoint unless
there is space in the accept queue to accept the newly created endpoint. If
there is no space then we again silently drop the ACK as we can just recreate it
when the ACK is retransmitted by the peer.
We also now use the backlog to cap the size of the SYN-RCVD queue for a given
endpoint. So at any time there can be N connections in the backlog and N in a
SYN-RCVD state if the application is not accepting connections. Any new SYNs
will be dropped.
This CL also fixes another small bug where we mark a new endpoint which has not
completed handshake as connected. We should wait till handshake successfully
completes before marking it connected.
Updates #236
PiperOrigin-RevId: 250717817
These wakers are uselessly allocated and passed around; nothing ever
listens for notifications on them. The code here appears to be
vestigial, so removing it and allowing a nil waker to be passed seems
appropriate.
PiperOrigin-RevId: 249879320
Change-Id: Icd209fb77cc0dd4e5c49d7a9f2adc32bf88b4b71
This is in preparation to support an fdbased endpoint that can read/dispatch
packets from multiple underlying fds.
Updates #231
PiperOrigin-RevId: 249337074
Change-Id: Id7d375186cffcf55ae5e38986e7d605a96916d35
And stop storing the Filesystem in the MountSource.
This allows us to decouple the MountSource filesystem type from the name of the
filesystem.
PiperOrigin-RevId: 247292982
Change-Id: I49cbcce3c17883b7aa918ba76203dfd6d1b03cc8
Some behavior was broken due to the difficulty of running automated raw
socket tests.
Change-Id: I152ca53916bb24a0208f2dc1c4f5bc87f4724ff6
PiperOrigin-RevId: 246747067
The tcpip.Clock comment stated that times provided by it should not be used for
netstack internal timekeeping. This comment was from before the interface
supported monotonic times. The monotonic times that it provides are now be the
preferred time source for netstack internal timekeeping.
PiperOrigin-RevId: 246618772
Change-Id: I853b720e3d719b03fabd6156d2431da05d354bda
- include packet_list.go
- exclude state.go (by renaming to include an underscore)
Also rename raw.go to endpoint.go for consistency.
PiperOrigin-RevId: 246547912
Change-Id: I19c8331c794ba683a940cc96a8be6497b53ff24d
Fixed a small logic error that broke proper accounting of MultiPortEndpoints.
PiperOrigin-RevId: 246502126
Change-Id: I1a7d6ea134f811612e545676212899a3707bc2c2
This requires two changes:
1) Support for more than one socket to join a given multicast group.
2) Duplicate delivery of incoming multicast packets to all sockets listening
for it.
In addition, I tweaked the code (and added a test) to disallow duplicates
IP_ADD_MEMBERSHIP calls for the same group and NIC. This is how Linux does
it.
PiperOrigin-RevId: 246437315
Change-Id: Icad8300b4a8c3f501d9b4cd283bd3beabef88b72
Based on the guidelines at
https://opensource.google.com/docs/releasing/authors/.
1. $ rg -l "Google LLC" | xargs sed -i 's/Google LLC.*/The gVisor Authors./'
2. Manual fixup of "Google Inc" references.
3. Add AUTHORS file. Authors may request to be added to this file.
4. Point netstack AUTHORS to gVisor AUTHORS. Drop CONTRIBUTORS.
Fixes#209
PiperOrigin-RevId: 245823212
Change-Id: I64530b24ad021a7d683137459cafc510f5ee1de9
Add the CloseRead & CloseWrite methods that performs shutdown on the
corresponding Read & Write sides of a connection.
Change-Id: I3996a2abdc7cd68a2becba44dc4bd9f0919d2ce1
PiperOrigin-RevId: 245537950
This CL fixes the following bugs:
- Uses atomic to set/read status instead of binary.LittleEndian.PutUint32 etc
which are not atomic.
- Increments ringOffsets for frames that are truncated (i.e status is
tpStatusCopy)
- Does not ignore frames with tpStatusLost bit set as they are valid frames and
only indicate that there some frames were lost before this one and metrics can
be retrieved with a getsockopt call.
- Adds checks to make sure blockSize is a multiple of page size. This is
required as the kernel allocates in pages per block and rejects sizes that are
not page aligned with an EINVAL.
Updates #210
PiperOrigin-RevId: 244959464
Change-Id: I5d61337b7e4c0f8a3063dcfc07791d4c4521ba1f
Support shutdown on only the read side of an endpoint. Reads performed
after a call to Shutdown with only the ShutdownRead flag will return
ErrClosedForReceive without data.
Break out the shutdown(2) with SHUT_RD syscall test into to two tests.
The first tests that no packets are sent when shutting down the read
side of a socket. The second tests that, after shutting down the read
side of a socket, unread data can still be read, or an EOF if there is
no more data to read.
Change-Id: I9d7c0a06937909cbb466b7591544a4bcaebb11ce
PiperOrigin-RevId: 244459430
It is possible to create a listening socket which will accept
IPv4 and IPv6 connections. In this case, we set IPv6ProtocolNumber
for all accepted endpoints, even if they handle IPv4 connections.
This means that we can't use endpoint.netProto to set gso.L3HdrLen.
PiperOrigin-RevId: 244227948
Change-Id: I5e1863596cb9f3d216febacdb7dc75651882eef1
Having raw socket code together will make it easier to add support for other raw
network protocols. Currently, only ICMP uses the raw endpoint. However, adding
support for other protocols such as UDP shouldn't be much more difficult than
adding a few switch cases.
PiperOrigin-RevId: 241564875
Change-Id: I77e03adafe4ce0fd29ba2d5dfdc547d2ae8f25bf
The panic was caused by modifying the tree while iterating which invalidated the
iterator.
Also fixes another bug in SACKScoreboard.Insert() which was causing blocks to be
merged incorrectly.
PiperOrigin-RevId: 240895053
Change-Id: Ia72b8244297962df5c04283346da5226434740af
The linux packet socket can handle GSO packets, so we can segment packets to
64K instead of the MTU which is usually 1500.
Here are numbers for the nginx-1m test:
runsc: 579330.01 [Kbytes/sec] received
runsc-gso: 1794121.66 [Kbytes/sec] received
runc: 2122139.06 [Kbytes/sec] received
and for tcp_benchmark:
$ tcp_benchmark --duration 15 --ideal
[ 4] 0.0-15.0 sec 86647 MBytes 48456 Mbits/sec
$ tcp_benchmark --client --duration 15 --ideal
[ 4] 0.0-15.0 sec 2173 MBytes 1214 Mbits/sec
$ tcp_benchmark --client --duration 15 --ideal --gso 65536
[ 4] 0.0-15.0 sec 19357 MBytes 10825 Mbits/sec
PiperOrigin-RevId: 240809103
Change-Id: I2637f104db28b5d4c64e1e766c610162a195775a
This is a preparation for GSO changes (cl/234508902).
RELNOTES[gofers]: Refactor checksum code to include length, which
it already did, but in a convoluted way. Should be a no-op.
PiperOrigin-RevId: 240460794
Change-Id: I537381bc670b5a9f5d70a87aa3eb7252e8f5ace2
Bhasker Hariharan
Adin Scannell
Rahat Mahmood
Andrei Vagin
Chris Kuiper
Fabricio Voznika
Tamir Duberstein
Kevin Krakauer
Nicolas Lacasse
Googler
Ian Gudger
Michael Pratt
Ben Burkert
Bert Muthalaly