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
When VectorisedViews were passed up the stack from packet_dispatchers, we were
passing a sub-slice of the dispatcher's views fields. The dispatchers then
immediately set those views to nil.
This wasn't caught before because every implementer copied the data in these
views before returning.
PiperOrigin-RevId: 277615351
This change supports using a user supplied TCP MSS for new active TCP
connections. Note, the user supplied MSS must be less than or equal to the
maximum possible MSS for a TCP connection's route. If it is greater than the
maximum possible MSS, the maximum possible MSS will be used as the connection's
MSS instead.
This change does not use this user supplied MSS for connections accepted from
listening sockets - that will come in a later change.
Test: Test that outgoing TCP SYN segments contain a TCP MSS option with the user
supplied MSS if it is not greater than the maximum possible MSS for the route.
PiperOrigin-RevId: 277185125
This change makes it so that NDP work is done using the per-interface NDP
configurations instead of the stack-wide default NDP configurations to correctly
implement RFC 4861 section 6.3.2 (note here, a host is a single NIC operating
as a host device), and RFC 4862 section 5.1.
Test: Test that we can set NDP configurations on a per-interface basis without
affecting the configurations of other interfaces or the stack-wide default. Also
make sure that after the configurations are updated, the updated configurations
are used for NDP processes (e.g. Duplicate Address Detection).
PiperOrigin-RevId: 276525661
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
This change makes sure that when an address which is already known by a NIC and
has kind = permanentExpired gets promoted to permanent, the new
PrimaryEndpointBehavior is respected.
PiperOrigin-RevId: 276136317
This change adds support for optionally auto-generating an IPv6 link-local
address based on the NIC's MAC Address on NIC enable.
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 a link-local
address will not be auto-generated unless the stack is explicitly configured.
See `stack.Options` for more details. Specifically, see
`stack.Options.AutoGenIPv6LinkLocal`.
Tests: Tests to make sure that the IPb6 link-local address is only
auto-generated if the stack is specifically configured to do so. Also tests to
make sure that an auto-generated address goes through the DAD process.
PiperOrigin-RevId: 276059813
Like (AF_INET, SOCK_RAW) sockets, AF_PACKET sockets require CAP_NET_RAW. With
runsc, you'll need to pass `--net-raw=true` to enable them.
Binding isn't supported yet.
PiperOrigin-RevId: 275909366
It is quite legal to send from the ANY address (it is required for
DHCP). I can't figure out why the broadcast address was included here,
so removing that as well.
PiperOrigin-RevId: 275541954
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
The behavior for sending and receiving local broadcast (255.255.255.255)
traffic is as follows:
Outgoing
--------
* A broadcast packet sent on a socket that is bound to an interface goes out
that interface
* A broadcast packet sent on an unbound socket follows the route table to
select the outgoing interface
+ if an explicit route entry exists for 255.255.255.255/32, use that one
+ else use the default route
* Broadcast packets are looped back and delivered following the rules for
incoming packets (see next). This is the same behavior as for multicast
packets, except that it cannot be disabled via sockopt.
Incoming
--------
* Sockets wishing to receive broadcast packets must bind to either INADDR_ANY
(0.0.0.0) or INADDR_BROADCAST (255.255.255.255). No other socket receives
broadcast packets.
* Broadcast packets are multiplexed to all sockets matching it. This is the
same behavior as for multicast packets.
* A socket can bind to 255.255.255.255:<port> and then receive its own
broadcast packets sent to 255.255.255.255:<port>
In addition, this change implicitly fixes an issue with multicast reception. If
two sockets want to receive a given multicast stream and one is bound to ANY
while the other is bound to the multicast address, only one of them will
receive the traffic.
PiperOrigin-RevId: 272792377
Non-primary addresses are used for endpoints created to accept multicast and
broadcast packets, as well as "helper" endpoints (0.0.0.0) that allow sending
packets when no proper address has been assigned yet (e.g., for DHCP). These
addresses are not real addresses from a user point of view and should not be
part of the NICInfo() value. Also see b/127321246 for more info.
This switches NICInfo() to call a new NIC.PrimaryAddresses() function. To still
allow an option to get all addresses (mostly for testing) I added
Stack.GetAllAddresses() and NIC.AllAddresses().
In addition, the return value for GetMainNICAddress() was changed for the case
where the NIC has no primary address. Instead of returning an error here,
it now returns an empty AddressWithPrefix() value. The rational for this
change is that it is a valid case for a NIC to have no primary addresses.
Lastly, I refactored the code based on the new additions.
PiperOrigin-RevId: 270971764
The IPv6 all-nodes multicast address will be joined on NIC enable, and the
appropriate IPv6 solicited-node multicast address will be joined when IPv6
addresses are added.
Tests: Test receiving packets destined to the IPv6 link-local all-nodes
multicast address and the IPv6 solicted node address of an added IPv6 address.
PiperOrigin-RevId: 268047073
This also renames "subnet" to "addressRange" to avoid any more confusion with
an interface IP's subnet.
Lastly, this also removes the Stack.ContainsSubnet(..) API since it isn't used
by anyone. Plus the same information can be obtained from
Stack.NICAddressRanges().
PiperOrigin-RevId: 267229843
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
This addresses the problem where an endpoint has its address removed but still
has outstanding references held by routes used in connected TCP/UDP sockets
which prevent the removal of the endpoint.
The fix adds a new "expired" flag to the referenced network endpoint, which is
set when an endpoint has its address removed. Incoming packets are not
delivered to an expired endpoint (unless in promiscuous mode), while sending
outgoing packets triggers an error to the caller (unless in spoofing mode).
In addition, a few helper functions were added to stack_test.go to reduce
code duplications.
PiperOrigin-RevId: 265514326
This adds the same logic to NIC.findEndpoint that is already done in
NIC.getRef. Since this makes the two functions very similar they were combined
into one with the originals being wrappers.
PiperOrigin-RevId: 263864708
This allows the user code to add a network address with a subnet prefix length.
The prefix length value is stored in the network endpoint and provided back to
the user in the ProtocolAddress type.
PiperOrigin-RevId: 259807693
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
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
HandleLocal is very similar conceptually to MULTICAST_LOOP, so we can unify
the implementations. This has the benefit of making HandleLocal apply even when
the fdbased link endpoint isn't in use.
In addition, move looping logic to route creation so that it doesn't need to be
run for each packet. This should improve performance.
PiperOrigin-RevId: 238099480
Change-Id: I72839f16f25310471453bc9d3fb8544815b25c23
IP_MULTICAST_LOOP controls whether or not multicast packets sent on the default
route are looped back. In order to implement this switch, support for sending
and looping back multicast packets on the default route had to be implemented.
For now we only support IPv4 multicast.
PiperOrigin-RevId: 237534603
Change-Id: I490ac7ff8e8ebef417c7eb049a919c29d156ac1c
Broadly, this change:
* Enables sockets to be created via `socket(AF_INET, SOCK_RAW, IPPROTO_ICMP)`.
* Passes the network-layer (IP) header up the stack to the transport endpoint,
which can pass it up to the socket layer. This allows a raw socket to return
the entire IP packet to users.
* Adds functions to stack.TransportProtocol, stack.Stack, stack.transportDemuxer
that enable incoming packets to be delivered to raw endpoints. New raw sockets
of other protocols (not ICMP) just need to register with the stack.
* Enables ping.endpoint to return IP headers when created via SOCK_RAW.
PiperOrigin-RevId: 235993280
Change-Id: I60ed994f5ff18b2cbd79f063a7fdf15d093d845a
An earlier CL excessively minimizes the period in which it
holds a lock on NIC. This earlier CL had done this out of
the mistaken impression it fixed a broken test, when in
fact it just reduced the rate of failure of a flaky test
in tcp_test.go. This new change holds the lock on NIC
for the duration of the loop over n.endpoints.
PiperOrigin-RevId: 235732487
Change-Id: I53ee6df264f093ddc4d29e9acdcba6b4838cb112
cl/234850781 introduced a race condition in NIC.DeliverNetworkPacket
by failing to hold a lock. This change fixes this regressesion by acquiring
a read lock before iterating through n.endpoints, and then releasing the lock
once iteration is complete.
PiperOrigin-RevId: 235549770
Change-Id: Ib0133288be512d478cf759c3314dc95ec3205d4b
This change adds support for the SO_BROADCAST socket option in gVisor Netstack.
This support includes getsockopt()/setsockopt() functionality for both UDP and
TCP endpoints (the latter being a NOOP), dispatching broadcast messages up and
down the stack, and route finding/creation for broadcast packets. Finally, a
suite of tests have been implemented, exercising this functionality through the
Linux syscall API.
PiperOrigin-RevId: 234850781
Change-Id: If3e666666917d39f55083741c78314a06defb26c
This removes code that should have never made it in in the first place, but did so due to incomplete testing. With the new tests the original code fails, the new code passes.
PiperOrigin-RevId: 224086966
Change-Id: I646fef76977f4528f3705f497b95fad6b3ec32bc
...to (remote, local), reflecting the (correct) names in the implementation of
DeliverNetworkPacket (see tcpip/stack/nic.go).
Also trim the names in DeliverNetworkPacket and elsewhere to avoid stuttering;
since the type is tcpip.LinkAddress, there's no need to include "LinkAddr" in
the parameter names.
Note that every callsite passes arguments in the order (src, dst).
PiperOrigin-RevId: 221514396
Change-Id: I3637454ad0d6e62a19e4dcbc2a16493798bd0f09
This allows a NetworkDispatcher to implement transparent bridging,
assuming all implementations of LinkEndpoint.WritePacket call eth.Encode
with header.EthernetFields.SrcAddr set to the passed
Route.LocalLinkAddress, if it is provided.
PiperOrigin-RevId: 213686651
Change-Id: I446a4ac070970202f0724ef796ff1056ae4dd72a
Now that it's possible to remove subnets, we must iterate over them with locks
held.
Also do the removal more efficiently while I'm here.
PiperOrigin-RevId: 211737416
Change-Id: I29025ec8b0c3ad11f22d4447e8ad473f1c785463