Changes the API of tcpip.Clock to also provide a method for scheduling and
rescheduling work after a specified duration. This change also implements the
AfterFunc method for existing implementations of tcpip.Clock.
This is the groundwork required to mock time within tests. All references to
CancellableTimer has been replaced with the tcpip.Job interface, allowing for
custom implementations of scheduling work.
This is a BREAKING CHANGE for clients that implement their own tcpip.Clock or
use tcpip.CancellableTimer. Migration plan:
1. Add AfterFunc(d, f) to tcpip.Clock
2. Replace references of tcpip.CancellableTimer with tcpip.Job
3. Replace calls to tcpip.CancellableTimer#StopLocked with tcpip.Job#Cancel
4. Replace calls to tcpip.CancellableTimer#Reset with tcpip.Job#Schedule
5. Replace calls to tcpip.NewCancellableTimer with tcpip.NewJob.
PiperOrigin-RevId: 322906897
Previously, ICMP destination unreachable datagrams were ignored by TCP
endpoints. This caused connect to hang when an intermediate router
couldn't find a route to the host.
This manifested as a Kokoro error when Docker IPv6 was enabled. The Ruby
image test would try to install the sinatra gem and hang indefinitely
attempting to use an IPv6 address.
Fixes#3079.
Fixes a NAT bug that manifested as:
- A SYN was sent from gVisor to another host, unaffected by iptables.
- The corresponding SYN/ACK was NATted by a PREROUTING REDIRECT rule
despite being part of the existing connection.
- The socket that sent the SYN never received the SYN/ACK and thus a
connection could not be established.
We handle this (as Linux does) by tracking all connections, inserting a
no-op conntrack rule for new connections with no rules of their own.
Needed for istio support (#170).
gVisor incorrectly returns the wrong ARP type for SIOGIFHWADDR. This breaks
tcpdump as it tries to interpret the packets incorrectly.
Similarly, SIOCETHTOOL is used by tcpdump to query interface properties which
fails with an EINVAL since we don't implement it. For now change it to return
EOPNOTSUPP to indicate that we don't support the query rather than return
EINVAL.
NOTE: ARPHRD types for link endpoints are distinct from NIC capabilities
and NIC flags. In Linux all 3 exist eg. ARPHRD types are stored in dev->type
field while NIC capabilities are more like the device features which can be
queried using SIOCETHTOOL but not modified and NIC Flags are fields that can
be modified from user space. eg. NIC status (UP/DOWN/MULTICAST/BROADCAST) etc.
Updates #2746
PiperOrigin-RevId: 321436525
The current convention is when a header is set to pkt.XxxHeader field, it
gets removed from pkt.Data. ICMP does not currently follow this convention.
PiperOrigin-RevId: 320078606
- Split connTrackForPacket into 2 functions instead of switching on flag
- Replace hash with struct keys.
- Remove prefixes where possible
- Remove unused connStatus, timeout
- Flatten ConnTrack struct a bit - some intermediate structs had no meaning
outside of the context of their parent.
- Protect conn.tcb with a mutex
- Remove redundant error checking (e.g. when is pkt.NetworkHeader valid)
- Clarify that HandlePacket and CreateConnFor are the expected entrypoints for
ConnTrack
PiperOrigin-RevId: 318407168
Linux controls socket send/receive buffers using a few sysctl variables
- net.core.rmem_default
- net.core.rmem_max
- net.core.wmem_max
- net.core.wmem_default
- net.ipv4.tcp_rmem
- net.ipv4.tcp_wmem
The first 4 control the default socket buffer sizes for all sockets
raw/packet/tcp/udp and also the maximum permitted socket buffer that can be
specified in setsockopt(SOL_SOCKET, SO_(RCV|SND)BUF,...).
The last two control the TCP auto-tuning limits and override the default
specified in rmem_default/wmem_default as well as the max limits.
Netstack today only implements tcp_rmem/tcp_wmem and incorrectly uses it
to limit the maximum size in setsockopt() as well as uses it for raw/udp
sockets.
This changelist introduces the other 4 and updates the udp/raw sockets to use
the newly introduced variables. The values for min/max match the current
tcp_rmem/wmem values and the default value buffers for UDP/RAW sockets is
updated to match the linux value of 212KiB up from the really low current value
of 32 KiB.
Updates #3043Fixes#3043
PiperOrigin-RevId: 318089805
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
Metadata was useful for debugging and safety, but enough tests exist that we
should see failures when (de)serialization is broken. It made stack
initialization more cumbersome and it's also getting in the way of ip6tables.
PiperOrigin-RevId: 317210653
... to help reduce flakes.
When waiting for an event to occur, use a timeout of 10s. When waiting
for an event to not occur, use a timeout of 1s.
Test: Ran test locally w/ run count of 1000 with and without gotsan.
PiperOrigin-RevId: 316998128
Tentative addresses should not be used when finding a route. This change
fixes a bug where a tentative address may have been used.
Test: stack_test.TestDADResolve
PiperOrigin-RevId: 315997624
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
NDP packets are sent periodically from NDP timers. These timers do not
hold the NIC lock when sending packets as the packet write operation
may take some time. While the lock is not held, the NIC may be removed
by some other goroutine. This change handles that scenario gracefully.
Test: stack_test.TestRemoveNICWhileHandlingRSTimer
PiperOrigin-RevId: 315524143
Sam Balana
Kevin Krakauer
gVisor bot
Bhasker Hariharan
Ghanan Gowripalan
Ting-Yu Wang
Ian Gudger