Marks the structs in netstack as savable. This does not change or break any
existing behavior as the netstack itself is not savable yet.
PiperOrigin-RevId: 635943481
Drop PickEphemeralPortStable which uses a hash-based algorithm from RFC 6056,
instead just use PickEphemeralPort that uses a randomized algorithm from RFC
6056 to avoid potential security concerns.
Discovered by Inon Kaplan (PhD candidate in the Hebrew University School of
Computer Science and Engineering), Ron Even (BSc graduate of Bar Ilan
University) and Amit Klein (faculty member in the Hebrew University School of
Computer Science and Engineering). Details will be provided in their paper, to
be presented in a forthcoming academic conference.
PiperOrigin-RevId: 581334218
This addresses an issue discovered by Inon Kaplan (PhD candidate in the
Hebrew University School of Computer Science and Engineering), Ron Even (BSc
graduate of Bar Ilan University) and Amit Klein (faculty member in the Hebrew
University School of Computer Science and Engineering). Details will be
provided in their paper, to be presented in a forthcoming academic conference.
Also:
- Add a secure RNG type to prevent mixing up with the default PRNG
- Give the PRNG the name `InsecureRNG` to make it more obvious to future
contributors that some RNGs are inappropriate in certain instances.
- Some tests were injecting fake RNGs and had to be relaxed: they relied on the
stack calling the RNG a specific number of times and in a specific order.
That order is now changed, and is too brittle to unit test.
- Remove the double package comment in pkg/rand. The linter complains.
PiperOrigin-RevId: 577513723
It is an idea of running codespell as part of our presubmit checks.
Before enabling it for new changes, let's fix what it has found.
Signed-off-by: Andrei Vagin <avagin@gmail.com>
The important change here is in tcpip/tcpip.go, where tcpip.Address is defined.
The rest is updating uses of tcpip.Address.
This is preparation for netip.Addr or []byte based addresses, which should save
us a bunch of allocations. Currently, we allocate every time we want to, say,
get a tcpip.Address from a header. This is because the header is a byte slice,
but Address is a string. Strings are immutable, so Go allocates and copies.
PiperOrigin-RevId: 532284732
In gVisor today its possible that when trying to bind a TCP socket
w/ SO_REUSEADDR specified and requesting the kernel pick a port by
setting port to zero can result in a previously bound port being
returned. This behaviour is incorrect as the user is clearly requesting
a free port. The behaviour is fine when the user explicity specifies
a port.
This change now checks if the user specified a port when making a port
reservation for a TCP port and only returns unbound ports even if
SO_REUSEADDR was specified.
Fixes#6209
PiperOrigin-RevId: 382607638
This was semi-automated -- there are many addresses that were not replaced.
Future commits should clean those up.
Parse4 and Parse6 were given their own package because //pkg/test can introduce
dependency cycles, as it depends transitively on //pkg/tcpip and some other
netstack packages.
PiperOrigin-RevId: 368726528
Lots of small changes:
- simplify package API via Reservation type
- rename some single-letter variable names that were hard to follow
- rename some types
PiperOrigin-RevId: 362442366
For TCP sockets, SO_REUSEADDR relaxes the rules for binding addresses.
gVisor/netstack already supported a behavior similar to SO_REUSEADDR, but did
not allow disabling it. This change brings the SO_REUSEADDR behavior closer to
the behavior implemented by Linux and adds a new SO_REUSEADDR disabled
behavior. Like Linux, SO_REUSEADDR is now disabled by default.
PiperOrigin-RevId: 317984380
On UDP sockets, SO_REUSEADDR allows multiple sockets to bind to the same
address, but only delivers packets to the most recently bound socket. This
differs from the behavior of SO_REUSEADDR on TCP sockets. SO_REUSEADDR for TCP
sockets will likely need an almost completely independent implementation.
SO_REUSEADDR has some odd interactions with the similar SO_REUSEPORT. These
interactions are tested fairly extensively and all but one particularly odd
one (that honestly seems like a bug) behave the same on gVisor and Linux.
PiperOrigin-RevId: 315844832
* Rename syncutil to sync.
* Add aliases to sync types.
* Replace existing usage of standard library sync package.
This will make it easier to swap out synchronization primitives. For example,
this will allow us to use primitives from github.com/sasha-s/go-deadlock to
check for lock ordering violations.
Updates #1472
PiperOrigin-RevId: 289033387
Netstack always picks a random start point everytime PickEphemeralPort
is called. While this is required for UDP so that DNS requests go
out through a randomized set of ports it is not required for TCP. Infact
Linux explicitly hashes the (srcip, dstip, dstport) and a one time secret
initialized at start of the application to get a random offset. But to
ensure it doesn't start from the same point on every scan it uses a static
hint that is incremented by 2 in every call to pick ephemeral ports.
The reason for 2 is Linux seems to split the port ranges where active connects
seem to use even ones while odd ones are used by listening sockets.
This CL implements a similar strategy where we use a hash + hint to generate
the offset to start the search for a free Ephemeral port.
This ensures that we cycle through the available port space in order for
repeated connects to the same destination and significantly reduces the
chance of picking a recently released port.
PiperOrigin-RevId: 272058370
