Add code in IPv6 to send ICMP packets while processing extension headers.
Add some accounting in processing IPV6 Extension headers which
allows us to report meaningful information back in ICMP parameter
problem packets.
IPv4 also needs to send a message when an unsupported protocol
is requested.
Add some tests to generate both ipv4 and ipv6 packets with
various errors and check the responses.
Add some new checkers and cleanup some inconsistencies in
the messages in that file.
Add new error types for the ICMPv4/6 generators.
Fix a bug in the ICMPv4 generator that stopped it from generating
"Unknown protocol" messages.
Updates #2211
PiperOrigin-RevId: 334661716
* Remove Capabilities and NICID methods from NetworkEndpoint.
* Remove linkEP and stack parameters from NetworkProtocol.NewEndpoint.
The LinkEndpoint can be fetched from the NetworkInterface. The stack
is passed to the NetworkProtocol when it is created so the
NetworkEndpoint can get it from its protocol.
* Remove stack parameter from TransportProtocol.NewEndpoint.
Like the NetworkProtocol/Endpoint, the stack is passed to the
TransportProtocol when it is created.
PiperOrigin-RevId: 334332721
* Add network address to network endpoints.
Hold network-specific state in the NetworkEndpoint instead of the stack.
This results in the stack no longer needing to "know" about the network
endpoints and special case certain work for various endpoints
(e.g. IPv6 DAD).
* Provide NetworkEndpoints with an NetworkInterface interface.
Instead of just passing the NIC ID of a NIC, pass an interface so the
network endpoint may query other information about the NIC such as
whether or not it is a loopback device.
* Move NDP code and state to the IPv6 package.
NDP is IPv6 specific so there is no need for it to live in the stack.
* Control forwarding through NetworkProtocols instead of Stack
Forwarding should be controlled on a per-network protocol basis so
forwarding configurations are now controlled through network protocols.
* Remove stack.referencedNetworkEndpoint.
Now that addresses are exposed via AddressEndpoint and only one
NetworkEndpoint is created per interface, there is no need for a
referenced NetworkEndpoint.
* Assume network teardown methods are infallible.
Fixes#3871, #3916
PiperOrigin-RevId: 334319433
Generic ICMP errors were required because the transport dispatcher was
given the responsibility of sending ICMP errors in response to transport
packet delivery failures. Instead, the transport dispatcher should let
network layer know it failed to deliver a packet (and why) and let the
network layer make the decision as to what error to send (if any).
Fixes#4068
PiperOrigin-RevId: 333962333
This change adds an option to replace the current implementation of ARP through
linkAddrCache, with an implementation of NUD through neighborCache. Switching
to using NUD for both ARP and NDP is beneficial for the reasons described by
RFC 4861 Section 3.1:
"[Using NUD] significantly improves the robustness of packet delivery in the
presence of failing routers, partially failing or partitioned links, or nodes
that change their link-layer addresses. For instance, mobile nodes can move
off-link without losing any connectivity due to stale ARP caches."
"Unlike ARP, Neighbor Unreachability Detection detects half-link failures and
avoids sending traffic to neighbors with which two-way connectivity is
absent."
Along with these changes exposes the API for querying and operating the
neighbor cache. Operations include:
- Create a static entry
- List all entries
- Delete all entries
- Remove an entry by address
This also exposes the API to change the NUD protocol constants on a per-NIC
basis to allow Neighbor Discovery to operate over links with widely varying
performance characteristics. See [RFC 4861 Section 10][1] for the list of
constants.
Finally, an API for subscribing to NUD state changes is exposed through
NUDDispatcher. See [RFC 4861 Appendix C][3] for the list of edges.
Tests:
pkg/tcpip/network/arp:arp_test
+ TestDirectRequest
pkg/tcpip/network/ipv6:ipv6_test
+ TestLinkResolution
+ TestNDPValidation
+ TestNeighorAdvertisementWithTargetLinkLayerOption
+ TestNeighorSolicitationResponse
+ TestNeighorSolicitationWithSourceLinkLayerOption
+ TestRouterAdvertValidation
pkg/tcpip/stack:stack_test
+ TestCacheWaker
+ TestForwardingWithFakeResolver
+ TestForwardingWithFakeResolverManyPackets
+ TestForwardingWithFakeResolverManyResolutions
+ TestForwardingWithFakeResolverPartialTimeout
+ TestForwardingWithFakeResolverTwoPackets
+ TestIPv6SourceAddressSelectionScopeAndSameAddress
[1]: https://tools.ietf.org/html/rfc4861#section-10
[2]: https://tools.ietf.org/html/rfc4861#appendix-CFixes#1889Fixes#1894Fixes#1895Fixes#1947Fixes#1948Fixes#1949Fixes#1950
PiperOrigin-RevId: 328365034
The NetworkEndpoint does not need to be created for each address.
Most of the work the NetworkEndpoint does is address agnostic.
PiperOrigin-RevId: 326759605
Formerly, when a packet is constructed or parsed, all headers are set by the
client code. This almost always involved prepending to pk.Header buffer or
trimming pk.Data portion. This is known to prone to bugs, due to the complexity
and number of the invariants assumed across netstack to maintain.
In the new PacketHeader API, client will call Push()/Consume() method to
construct/parse an outgoing/incoming packet. All invariants, such as slicing
and trimming, are maintained by the API itself.
NewPacketBuffer() is introduced to create new PacketBuffer. Zero value is no
longer valid.
PacketBuffer now assumes the packet is a concatenation of following portions:
* LinkHeader
* NetworkHeader
* TransportHeader
* Data
Any of them could be empty, or zero-length.
PiperOrigin-RevId: 326507688
Packets MUST NOT use a non-unicast source address for ICMP
Echo Replies.
Test: integration_test.TestPingMulticastBroadcast
PiperOrigin-RevId: 325634380
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.
Netstack has traditionally parsed headers on-demand as a packet moves up the
stack. This is conceptually simple and convenient, but incompatible with
iptables, where headers can be inspected and mangled before even a routing
decision is made.
This changes header parsing to happen early in the incoming packet path, as soon
as the NIC gets the packet from a link endpoint. Even if an invalid packet is
found (e.g. a TCP header of insufficient length), the packet is passed up the
stack for proper stats bookkeeping.
PiperOrigin-RevId: 315179302
Historically we've been passing PacketBuffer by shallow copying through out
the stack. Right now, this is only correct as the caller would not use
PacketBuffer after passing into the next layer in netstack.
With new buffer management effort in gVisor/netstack, PacketBuffer will
own a Buffer (to be added). Internally, both PacketBuffer and Buffer may
have pointers and shallow copying shouldn't be used.
Updates #2404.
PiperOrigin-RevId: 314610879
These methods let users eaily break the VectorisedView abstraction, and
allowed netstack to slip into pseudo-enforcement of the "all headers are
in the first View" invariant. Removing them and replacing with PullUp(n)
breaks this reliance and will make it easier to add iptables support and
rework network buffer management.
The new View.PullUp(n) method is low cost in the common case, when when
all the headers fit in the first View.
PiperOrigin-RevId: 308163542
These methods let users eaily break the VectorisedView abstraction, and
allowed netstack to slip into pseudo-enforcement of the "all headers are
in the first View" invariant. Removing them and replacing with PullUp(n)
breaks this reliance and will make it easier to add iptables support and
rework network buffer management.
The new View.PullUp(n) method is low cost in the common case, when when
all the headers fit in the first View.
Better validate NDP NAs options before updating the link address cache.
Test: stack_test.TestNeighorAdvertisementWithTargetLinkLayerOption
PiperOrigin-RevId: 306962924
Better validate NDP NS messages and their options before doing work in
response to them. Also make sure that NA messages sent in response to
an NS use the correct IPv6 and link-layer addresses so they are
routed properly and received by the right node.
Test: stack_test.TestNeighorSolicitationResponse
PiperOrigin-RevId: 305799054
Software GSO implementation currently has a complicated code path with
implicit assumptions that all packets to WritePackets carry same Data
and it does this to avoid allocations on the path etc. But this makes it
hard to reuse the WritePackets API.
This change breaks all such assumptions by introducing a new Vectorised
View API ReadToVV which can be used to cleanly split a VV into multiple
independent VVs. Further this change also makes packet buffers linkable
to form an intrusive list. This allows us to get rid of the array of
packet buffers that are passed in the WritePackets API call and replace
it with a list of packet buffers.
While this code does introduce some more allocations in the benchmarks
it doesn't cause any degradation.
Updates #231
PiperOrigin-RevId: 304731742
As per RFC 6980 section 5, nodes MUST silently ignore NDP messages if
the packet carrying them include an IPv6 Fragmentation Header.
Test: ipv6_test.TestNDPValidation
PiperOrigin-RevId: 304519379
This is a precursor to be being able to build an intrusive list
of PacketBuffers for use in queuing disciplines being implemented.
Updates #2214
PiperOrigin-RevId: 302677662
Get the link address for the target of an NDP Neighbor Advertisement
from the NDP Target Link Layer Address option.
Tests:
- ipv6.TestNeighorAdvertisementWithTargetLinkLayerOption
- ipv6.TestNeighorAdvertisementWithInvalidTargetLinkLayerOption
PiperOrigin-RevId: 293632609
As per RFC 2464 section 7, an IPv6 packet with a multicast destination
address is transmitted to the mapped Ethernet multicast address.
Test:
- ipv6.TestLinkResolution
- stack_test.TestDADResolve
- stack_test.TestRouterSolicitation
PiperOrigin-RevId: 292610529
Update link address for senders of NDP Neighbor Solicitations when the NS
contains an NDP Source Link Layer Address option.
Tests:
- ipv6.TestNeighorSolicitationWithSourceLinkLayerOption
- ipv6.TestNeighorSolicitationWithInvalidSourceLinkLayerOption
PiperOrigin-RevId: 292028553
This change validates incoming NDP Router Advertisements as per RFC 4861 section
6.1.2. It also includes the skeleton to handle Router Advertiements that arrive
on some NIC.
Tests: Unittest to make sure only valid NDP Router Advertisements are received/
not dropped.
PiperOrigin-RevId: 278891972
This change validates the ICMPv6 checksum field before further processing an
ICMPv6 packet.
Tests: Unittests to make sure that only ICMPv6 packets with a valid checksum
are accepted/processed. Existing tests using checker.ICMPv6 now also check the
ICMPv6 checksum field.
PiperOrigin-RevId: 276779148
This change introduces a new interface, stack.NDPDispatcher. It can be
implemented by the netstack integrator to receive NDP related events. As of this
change, only DAD related events are supported.
Tests: Existing tests were modified to use the NDPDispatcher's DAD events for
DAD tests where it needed to wait for DAD completing (failing and resolving).
PiperOrigin-RevId: 276338733
NDP Neighbor Solicitations sent during Duplicate Address Detection must have an
IP hop limit of 255, as all NDP Neighbor Solicitations should have.
Test: Test that DAD messages have the IPv6 hop limit field set to 255.
PiperOrigin-RevId: 275321680
This change adds support for Duplicate Address Detection on IPv6 addresses
as defined by RFC 4862 section 5.4.
Note, this change will not break existing uses of netstack as the default
configuration for the stack options is set in such a way that DAD will not be
performed. See `stack.Options` and `stack.NDPConfigurations` for more details.
Tests: Tests to make sure that the DAD process properly resolves or fails.
That is, tests make sure that DAD resolves only if:
- No other node is performing DAD for the same address
- No other node owns the same address
PiperOrigin-RevId: 275189471
...and do not populate link address cache at dispatch. This partially
reverts 313c767b00, which caused malformed
packets (e.g. NDP Neighbor Adverts with incorrect hop limit values) to
populate the address cache. In particular, this masked a bug that was
introduced to the Neighbor Advert generation code in
7c1587e340.
PiperOrigin-RevId: 274865182
Adds support to generate Port Unreachable messages for UDP
datagrams received on a port for which there is no valid
endpoint.
Fixes#703
PiperOrigin-RevId: 267034418
This allows the stack to learn remote link addresses on incoming
packets, reducing the need to ARP to send responses.
This also reduces the number of round trips to the system clock,
since that may also prove to be performance-sensitive.
Fixes#739.
PiperOrigin-RevId: 265815816
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
Peter Johnston
Julian Elischer
Ghanan Gowripalan
gVisor bot
Sam Balana
Ting-Yu Wang
Kevin Krakauer
Bhasker Hariharan
Tamir Duberstein
Ian Gudger
Adin Scannell
Michael Pratt
Nicolas Lacasse
Bert Muthalaly