summaryrefslogtreecommitdiffhomepage
path: root/pkg/tcpip
AgeCommit message (Collapse)Author
2021-03-03Assert UpdatedAtNanos in neighbor cache testsSam Balana
Changes the neighbor_cache_test.go tests to always assert UpdatedAtNanos. Completes the assertion of UpdatedAtNanos in every NUD test, a field that was historically not checked due to the lack of a deterministic, controllable clock. This is no longer true with the tcpip.Clock interface. While the tests have been adjusted to use Clock, asserting by the UpdatedAtNanos was neglected. Fixes #4663 PiperOrigin-RevId: 360730077
2021-03-03Add checklocks analyzer.Bhasker Hariharan
This validates that struct fields if annotated with "// checklocks:mu" where "mu" is a mutex field in the same struct then access to the field is only done with "mu" locked. All types that are guarded by a mutex must be annotated with // +checklocks:<mutex field name> For more details please refer to README.md. PiperOrigin-RevId: 360729328
2021-03-03Export stats that were forgottenArthur Sfez
While I'm here, simplify the comments and unify naming of certain stats across protocols. PiperOrigin-RevId: 360728849
2021-03-03[op] Replace syscall package usage with golang.org/x/sys/unix in pkg/.Ayush Ranjan
The syscall package has been deprecated in favor of golang.org/x/sys. Note that syscall is still used in the following places: - pkg/sentry/socket/hostinet/stack.go: some netlink related functionalities are not yet available in golang.org/x/sys. - syscall.Stat_t is still used in some places because os.FileInfo.Sys() still returns it and not unix.Stat_t. Updates #214 PiperOrigin-RevId: 360701387
2021-03-02Plumb link address request errors up to requesterTamir Duberstein
Prevent the situation where callers to (*stack).GetLinkAddress provide incorrect arguments and are unable to observe this condition. Updates #5583. PiperOrigin-RevId: 360481557
2021-03-01tcp: endpoint.Write has to send all data that has been read from payloadAndrei Vagin
io.Reader.ReadFull returns the number of bytes copied and an error if fewer bytes were read. PiperOrigin-RevId: 360247614
2021-02-26Fix panic due to zero length writes in TCP.Bhasker Hariharan
There is a short race where in Write an endpoint can transition from writable to non-writable state due to say an incoming RST during the time we release the endpoint lock and reacquire after copying the payload. In such a case if the write happens to be a zero sized write we end up trying to call sendData() even though nothing was queued. This can panic when trying to enable/disable TCP timers if the endpoint had already transitioned to a CLOSED/ERROR state due to the incoming RST as we cleanup timers when the protocol goroutine terminates. Sadly the race window is small enough that my attempts at reproducing the panic in a syscall test has not been successful. PiperOrigin-RevId: 359887905
2021-02-26Assert UpdatedAtNanos in neighbor entry testsSam Balana
Changes the neighbor_entry_test.go tests to always assert UpdatedAtNanos. This field was historically not checked due to the lack of a deterministic, controllable clock. This is no longer true with the tcpip.Clock interface. While the tests have been adjusted to use Clock, asserting by the UpdatedAtNanos was neglected. Subsequent work is needed to assert UpdatedAtNanos in the neighbor cache tests. Updates #4663 PiperOrigin-RevId: 359868254
2021-02-26Embed sync.Mutex for entryTestLinkResolver and testNUDDispatcherSam Balana
Converts entryTestLinkResolver and testNUDDispatcher to use the embedded sync.Mutex pattern for fields that may be accessed concurrently from different gorountines. Fixes #5541 PiperOrigin-RevId: 359826169
2021-02-26Use helper functions in neighbor entry testsSam Balana
Adds helper functions for transitioning into common states. This reduces the boilerplate by a fair amount, decreasing the barriers to entry for new features added to neighborEntry. PiperOrigin-RevId: 359810465
2021-02-26Use closure to avoid manual unlockingTamir Duberstein
Also increase refcount of raw.endpoint.route while in use. Avoid allocating an array of size zero. PiperOrigin-RevId: 359797788
2021-02-25RACK: recovery logic should check for receive window before re-transmitting.Nayana Bidari
Use maybeSendSegment while sending segments in RACK recovery which checks if the receiver has space and splits the segments when the segment size is greater than MSS. PiperOrigin-RevId: 359641097
2021-02-25Remove deadlock in raw.endpoint caused by recursive read lockingKevin Krakauer
Prevents the following deadlock: - Raw packet is sent via e.Write(), which read locks e.mu - Connect() is called, blocking on write locking e.mu - The packet is routed to loopback and back to e.HandlePacket(), which read locks e.mu Per the atomic.RWMutex documentation, this deadlocks: "If a goroutine holds a RWMutex for reading and another goroutine might call Lock, no goroutine should expect to be able to acquire a read lock until the initial read lock is released. In particular, this prohibits recursive read locking. This is to ensure that the lock eventually becomes available; a blocked Lock call excludes new readers from acquiring the lock." Also, release eps.mu earlier in deliverRawPacket. PiperOrigin-RevId: 359600926
2021-02-24Validate MLD packetsArthur Sfez
Fixes #5490 PiperOrigin-RevId: 359401532
2021-02-24Cleanup temp SLAAC address jobs on DAD conflictsGhanan Gowripalan
Previously, when DAD would detect a conflict for a temporary address, the address would be removed but its timers would not be stopped, resulting in a panic when the removed address's invalidation timer fired. While I'm here, remove the check for unicast-ness on removed address endpoints since multicast addresses are no longer stored in the same structure as unicast addresses as of 27ee4fe76ad586ac8751951a842b3681f93. Test: stack_test.TestMixedSLAACAddrConflictRegen PiperOrigin-RevId: 359344849
2021-02-24Move //pkg/gate.Gate to //pkg/sync.Jamie Liu
- Use atomic add rather than CAS in every Gate method, which is slightly faster in most cases. - Implement Close wakeup using gopark/goready to avoid channel allocation. New benchmarks: name old time/op new time/op delta GateEnterLeave-12 16.7ns ± 1% 10.3ns ± 1% -38.44% (p=0.000 n=9+8) GateClose-12 50.2ns ± 8% 42.4ns ± 6% -15.44% (p=0.000 n=10+10) GateEnterLeaveAsyncClose-12 972ns ± 2% 640ns ± 7% -34.15% (p=0.000 n=9+10) PiperOrigin-RevId: 359336344
2021-02-18Bump build constraints to Go 1.18Michael Pratt
These are bumped to allow early testing of Go 1.17. Use will be audited closer to the 1.17 release. PiperOrigin-RevId: 358278615
2021-02-18Validate IGMP packetsArthur Sfez
This change also adds support for Router Alert option processing on incoming packets, a new stat for Router Alert option, and exports all the IP-option related stats. Fixes #5491 PiperOrigin-RevId: 358238123
2021-02-18Remove deprecated NUD types Failed and FailedEntryLookupsSam Balana
Completes the soft migration to Unreachable state by removing the Failed state and the the FailedEntryLookups StatCounter. Fixes #4667 PiperOrigin-RevId: 358226380
2021-02-17Move Name() out of netstack Matcher. It can live in the sentry.Kevin Krakauer
PiperOrigin-RevId: 358078157
2021-02-17[infra] Split tcpip/integration test targets to aid investigation.Ayush Ranjan
tcpip integration tests have been flaky lately. They usually run in 20 seconds and have a 60 seconds timeout. Sometimes they timeout which could be due to a bug or deadlock. To further investigate it might be helpful to split the targets and see which test is causing the flake. Added a new tcpip/tests/utils package to hold all common utilities across all tests. PiperOrigin-RevId: 358012936
2021-02-11[rack] TLP: ACK Processing and PTO scheduling.Ayush Ranjan
This change implements TLP details enumerated in https://tools.ietf.org/html/draft-ietf-tcpm-rack-08#section-7.5.3 Fixes #5085 PiperOrigin-RevId: 357125037
2021-02-11[netstack] Fix recovery entry and exit checks.Ayush Ranjan
Entry check: - Earlier implementation was preventing us from entering recovery even if SND.UNA is lost but dupAckCount is still below threshold. Fixed that. - We should only enter recovery when at least one more byte of data beyond the highest byte that was outstanding when fast retransmit was last entered is acked. Added that check. Exit check: - Earlier we were checking if SEG.ACK is in range [SND.UNA, SND.NXT]. The intention was to check if any unacknowledged data was ACKed. Note that (SEG.ACK - 1) is actually the sequence number which was ACKed. So we were incorrectly including (SND.UNA - 1) in the range. Fixed the check to now be (SEG.ACK - 1) in range [SND.UNA, SND.NXT). Additionally, moved a RACK specific test to the rack tests file. Added tests for the changes I made. PiperOrigin-RevId: 357091322
2021-02-11Let sentry understand tcpip.ErrMalformedHeaderKevin Krakauer
Added a LINT IfChange/ThenChange check to catch this in the future. PiperOrigin-RevId: 357077564
2021-02-10RACK: Fix re-transmitting the segment twice when entering recovery.Nayana Bidari
TestRACKWithDuplicateACK is flaky as the reorder window can expire before receiving three duplicate ACKs which will result in sending the first unacknowledged segment twice: when reorder timer expired and again after receiving the third duplicate ACK. This CL will fix this behavior and will not resend the segment again if it was already re-transmittted when reorder timer expired. Update the TestRACKWithDuplicateACK to test that the first segment is considered as lost and is re-transmitted. PiperOrigin-RevId: 356855168
2021-02-10Fix broken IFTTT link in tcpip.Ayush Ranjan
PiperOrigin-RevId: 356852625
2021-02-09Add support for setting SO_SNDBUF for unix domain sockets.Bhasker Hariharan
The limits for snd/rcv buffers for unix domain socket is controlled by the following sysctls on linux - net.core.rmem_default - net.core.rmem_max - net.core.wmem_default - net.core.wmem_max Today in gVisor we do not expose these sysctls but we do support setting the equivalent in netstack via stack.Options() method. But AF_UNIX sockets in gVisor can be used without netstack, with hostinet or even without any networking stack at all. Which means ideally these sysctls need to live as globals in gVisor. But rather than make this a big change for now we hardcode the limits in the AF_UNIX implementation itself (which in itself is better than where we were before) where it SO_SNDBUF was hardcoded to 16KiB. Further we bump the initial limit to a default value of 208 KiB to match linux from the paltry 16 KiB we use today. Updates #5132 PiperOrigin-RevId: 356665498
2021-02-09Move network internal code to internal packageGhanan Gowripalan
Utilities written to be common across IPv4/IPv6 are not planned to be available for public use. https://golang.org/doc/go1.4#internalpackages PiperOrigin-RevId: 356554862
2021-02-09Deprecate Failed state in favor of Unreachable stateSam Balana
... as per RFC 7048. The Failed state is an internal state that is not specified by any RFC; replacing it with the Unreachable state enables us to expose this state while keeping our terminology consistent with RFC 4861 and RFC 7048. Unreachable state replaces all internal references for Failed state. However unlike the Failed state, change events are dispatched when moving into Unreachable state. This gives developers insight into whether a neighbor entry failed address resolution or whether it was explicitly removed. The Failed state will be removed entirely once all references to it are removed. This is done to avoid a Fuchsia roll failure. Updates #4667 PiperOrigin-RevId: 356554104
2021-02-09add IPv4 options processing for forwarding and reassemblyJulian Elischer
IPv4 forwarding and reassembly needs support for option processing and regular processing also needs options to be processed before being passed to the transport layer. This patch extends option processing to those cases and provides additional testing. A small change to the ICMP error generation API code was required to allow it to know when a packet was being forwarded or not. Updates #4586 PiperOrigin-RevId: 356446681
2021-02-08Remove unnecessary lockingGhanan Gowripalan
The thing the lock protects will never be accessed concurrently. PiperOrigin-RevId: 356423331
2021-02-08Allow UDP sockets connect()ing to port 0Zeling Feng
We previously return EINVAL when connecting to port 0, however this is not the observed behavior on Linux. One of the observable effects after connecting to port 0 on Linux is that getpeername() will fail with ENOTCONN. PiperOrigin-RevId: 356413451
2021-02-08Support performing DAD for any addressGhanan Gowripalan
...as long as the network protocol supports duplicate address detection. This CL provides the facilities for a netstack integrator to perform DAD. DHCP recommends that clients effectively perform DAD before accepting an offer. As per RFC 2131 section 4.4.1 pg 38, The client SHOULD perform a check on the suggested address to ensure that the address is not already in use. For example, if the client is on a network that supports ARP, the client may issue an ARP request for the suggested request. The implementation of ARP-based IPv4 DAD effectively operates the same as IPv6's NDP DAD - using ARP requests and responses in place of NDP neighbour solicitations and advertisements, respectively. DAD performed by calls to (*Stack).CheckDuplicateAddress don't interfere with DAD performed when a new IPv6 address is added. This is so that integrator requests to check for duplicate addresses aren't unexpectedly aborted when addresses are removed. A network package internal package provides protocol agnostic DAD state management that specific protocols that provide DAD can use. Fixes #4550. Tests: - internal/ip_test.* - integration_test.TestDAD - arp_test.TestDADARPRequestPacket - ipv6.TestCheckDuplicateAddress PiperOrigin-RevId: 356405593
2021-02-08RACK: Detect lossNayana Bidari
Detect packet loss using reorder window and re-transmit them after the reorder timer expires. PiperOrigin-RevId: 356321786
2021-02-06Remove linkAddrCacheGhanan Gowripalan
It was replaced by NUD/neighborCache. Fixes #4658. PiperOrigin-RevId: 356085221
2021-02-06Synchronously send packets over pipe link endpointGhanan Gowripalan
Before this change, packets were delivered asynchronously to the remote end of a pipe. This was to avoid a deadlock during link resolution where the stack would attempt to double-lock a mutex (see removed comments in the parent commit for details). As of https://github.com/google/gvisor/commit/4943347137, we do not hold locks while sending link resolution probes so the deadlock will no longer occur. PiperOrigin-RevId: 356066224
2021-02-06Use fine grained locks while sending NDP packetsGhanan Gowripalan
Previously when sending NDP DAD or RS messages, we would hold a shared lock which lead to deadlocks (due to synchronous packet loooping (e.g. pipe and loopback link endpoints)) and lock contention. Writing packets may be an expensive operation which could prevent other goroutines from doing meaningful work if a shared lock is held while writing packets. This change upates the NDP DAD/RS timers to not hold shared locks while sending packets. PiperOrigin-RevId: 356053146
2021-02-06Remove (*stack.Stack).FindNetworkEndpointGhanan Gowripalan
The network endpoints only look for other network endpoints of the same kind. Since the network protocols keeps track of all endpoints, go through the protocol to find an endpoint with an address instead of the stack. PiperOrigin-RevId: 356051498
2021-02-06Use fine grained locks while sending NUD probesGhanan Gowripalan
Previously when sending probe messages, we would hold a shared lock which lead to deadlocks (due to synchronous packet loooping (e.g. pipe and loopback link endpoints)) and lock contention. Writing packets may be an expensive operation which could prevent other goroutines from doing meaningful work if a shared lock is held while writing packets. This change upates the NUD timers to not hold shared locks while sending packets. PiperOrigin-RevId: 356048697
2021-02-06Use embedded mutex pattern in neighbor cache/entryGhanan Gowripalan
Also while I'm here, update neighbor cahce/entry tests to use the stack's RNG instead of creating a neigbor cache/entry specific one. PiperOrigin-RevId: 356040581
2021-02-06Unexpose NICGhanan Gowripalan
The NIC structure is not to be used outside of the stack package directly. PiperOrigin-RevId: 356036737
2021-02-06Check local address directly through NICGhanan Gowripalan
Network endpoints that wish to check addresses on another NIC-local network endpoint may now do so through the NetworkInterface. This fixes a lock ordering issue between NIC removal and link resolution. Before this change: NIC Removal takes the stack lock, neighbor cache lock then neighbor entries' locks. When performing IPv4 link resolution, we take the entry lock then ARP would try check IPv4 local addresses through the stack which tries to obtain the stack's lock. Now that ARP can check IPv4 addreses through the NIC, we avoid the lock ordering issue, while also removing the need for stack to lookup the NIC. PiperOrigin-RevId: 356034245
2021-02-05Batch write packets after iptables checksGhanan Gowripalan
After IPTables checks a batch of packets, we can write packets that are not dropped or locally destined as a batch instead of individually. This previously caused a bug since WritePacket* functions expect to take ownership of passed PacketBuffer{List}. WritePackets assumed the list of PacketBuffers will not be invalidated when calling WritePacket for each PacketBuffer in the list, but this is not true. WritePacket may add the passed PacketBuffer into a different list which would modify the PacketBuffer in such a way that it no longer points to the next PacketBuffer to write. Example: Given a PB list of PB_a -> PB_b -> PB_c WritePackets may be iterating over the list and calling WritePacket for each PB. When WritePacket takes PB_a, it may add it to a new list which would update pointers such that PB_a no longer points to PB_b. Test: integration_test.TestIPTableWritePackets PiperOrigin-RevId: 355969560
2021-02-05Refactor locally delivered packetsGhanan Gowripalan
Make it clear that failing to parse a looped back is not a packet sending error but a malformed received packet error. FindNetworkEndpoint returns nil when no network endpoint is found instead of an error. PiperOrigin-RevId: 355954946
2021-02-04Lock ConnTrack before initializing bucketsGhanan Gowripalan
PiperOrigin-RevId: 355751801
2021-02-03Add a function to enable RACK in tests.Nayana Bidari
- Adds a function to enable RACK in tests. - RACK update functions are guarded behind the flag tcpRecovery. PiperOrigin-RevId: 355435973
2021-02-02Rename HandleNDupAcks in TCP.Nayana Bidari
Rename HandleNDupAcks() to HandleLossDetected() as it will enter this when is detected after: - reorder window expires and TLP (in case of RACK) - dupAckCount >= 3 PiperOrigin-RevId: 355237858
2021-02-02Add support for rate limiting out of window ACKs.Bhasker Hariharan
Netstack today will send dupACK's with no rate limit for incoming out of window segments. This can result in ACK loops for example if a TCP socket connects to itself (actually permitted by TCP). Where the ACK sent in response to packets being out of order itself gets considered as an out of window segment resulting in another ACK being generated. PiperOrigin-RevId: 355206877
2021-02-01Refactor HandleControlPacket/SockErrorGhanan Gowripalan
...to remove the need for the transport layer to deduce the type of error it received. Rename HandleControlPacket to HandleError as HandleControlPacket only handles errors. tcpip.SockError now holds a tcpip.SockErrorCause interface that different errors can implement. PiperOrigin-RevId: 354994306
2021-01-31Default to NUD/neighborCache instead of linkAddrCacheGhanan Gowripalan
This change flips gvisor to use Neighbor unreachability detection by default to populate the neighbor table as defined by RFC 4861 section 7. Although RFC 4861 is targeted at IPv6, the same algorithm is used for link resolution on IPv4 networks using ARP. Integrators may still use the legacy link address cache by setting stack.Options.UseLinkAddrCache to true; stack.Options.UseNeighborCache is now unused and will be removed. A later change will remove linkAddrCache and associated code. Updates #4658. PiperOrigin-RevId: 354850531