Extracted from some code written in the other repo.
Updates tailscale/corp#25479
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I92c97a63a8f35cace6e89a730938ea587dcefd9b
Otherwise we'll see a panic if we hit the dnsfallback code and try to
call NewDialer with a nil NetMon.
Updates #14161
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I81c6e72376599b341cb58c37134c2a948b97cf5f
This allows us to print the time that a netcheck was run, which is
useful in debugging.
Updates #10972
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Id48d30d4eb6d5208efb2b1526a71d83fe7f9320b
This fixes the installation on newer Fedora versions that use dnf5 as
the 'dnf' binary.
Updates #13828
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I39513243c81640fab244a32b7dbb3f32071e9fce
For a customer that wants to run their own DERP prober, let's add a
/healthz endpoint that can be used to monitor derpprobe itself.
Updates #6526
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Iba315c999fc0b1a93d8c503c07cc733b4c8d5b6b
Per my investigation just now, the $HOME environment variable is unset
on the macsys (standalone macOS GUI) variant, but the current working
directory is valid. Look for the environment variable file in that
location in addition to inside the home directory.
Updates #3707
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I481ae2e0d19b316244373e06865e3b5c3a9f3b88
We were previously not checking that the external IP that we got back
from a UPnP portmap was a valid endpoint; add minimal validation that
this endpoint is something that is routeable by another host.
Updates tailscale/corp#23538
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Id9649e7683394aced326d5348f4caa24d0efd532
This breaks its ability to be used as an expvar and is blocking a trunkd
deploy. Revert for now, and add a test to ensure that we don't break it
in a future change.
Updates #13550
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I1f1221c257c1de47b4bff0597c12f8530736116d
This un-breaks vim-go (which doesn't understand "go 1.23") and allows
the natlab tests to work in a Nix shell (by adding the "qemu-img" and
"mkfs.ext4" binaries to the shell). These binaries are available even on
macOS, as I'm testing on my M1 Max.
Updates #13038
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I99f8521b5de93ea47dc33b099d5b243ffc1303da
This mimics having Tailscale in the 'Stopped' state by programming an
empty DNS configuration when the current node key is expired.
Updates tailscale/support-escalations#55
Change-Id: I68ff4665761fb621ed57ebf879263c2f4b911610
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Discovered this while investigating the following issue; I think it's
unrelated, but might as well fix it. Also, add a test helper for
checking things that have an IsZero method using the reflect package.
Updates tailscale/support-escalations#55
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I57b7adde43bcef9483763b561da173b4c35f49e2
Previously, despite what the commit said, we were using a raw IP socket
that was *not* an AF_PACKET socket, and thus was subject to the host
firewall rules. Switch to using a real AF_PACKET socket to actually get
the functionality we want.
Updates #13140
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: If657daeeda9ab8d967e75a4f049c66e2bca54b78
By default, Windows sets the SIO_UDP_CONNRESET and SIO_UDP_NETRESET
options on created UDP sockets. These behaviours make the UDP socket
ICMP-aware; when the system gets an ICMP message (e.g. an "ICMP Port
Unreachable" message, in the case of SIO_UDP_CONNRESET), it will cause
the underlying UDP socket to throw an error. Confusingly, this can occur
even on reads, if the same UDP socket is used to write a packet that
triggers this response.
The Go runtime disabled the SIO_UDP_CONNRESET behavior in 3114bd6, but
did not change SIO_UDP_NETRESET–probably because that socket option
isn't documented particularly well.
Various other networking code seem to disable this behaviour, such as
the Godot game engine (godotengine/godot#22332) and the Eclipse TCF
agent (link below). Others appear to work around this by ignoring the
error returned (anacrolix/dht#16, among others).
For now, until it's clear whether this ends up in the upstream Go
implementation or not, let's also disable the SIO_UDP_NETRESET in a
similar manner to SIO_UDP_CONNRESET.
Eclipse TCF agent: https://gitlab.eclipse.org/eclipse/tcf/tcf.agent/-/blob/master/agent/tcf/framework/mdep.c
Updates #10976
Updates golang/go#68614
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I70a2f19855f8dec1bfb82e63f6d14fc4a22ed5c3
This turns the checklocks workflow into a real check, and adds
annotations to a few basic packages as a starting point.
Updates #12625
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I2b0185bae05a843b5257980fc6bde732b1bdd93f
We can observe a data race in tests when logging after a test is
finished. `b.onHealthChange` is called in a goroutine after being
registered with `health.Tracker.RegisterWatcher`, which calls callbacks
in `setUnhealthyLocked` in a new goroutine.
See: https://github.com/tailscale/tailscale/actions/runs/9672919302/job/26686038740
Updates #12054
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ibf22cc994965d88a9e7236544878d5373f91229e
Previously, if we had a umask set (e.g. 0027) that prevented creating a
world-readable file, /etc/resolv.conf would be created without the o+r
bit and thus other users may be unable to resolve DNS.
Since a umask only applies to file creation, chmod the file after
creation and before renaming it to ensure that it has the appropriate
permissions.
Updates #12609
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I2a05d64f4f3a8ee8683a70be17a7da0e70933137
The logic we added in #11378 would prevent selecting a home DERP if we
have no control connection.
Updates tailscale/corp#18095
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I44bb6ac4393989444e4961b8cfa27dc149a33c6e
This adds the ability to "peek" at the value of a SyncValue, so that
it's possible to observe a value without computing this.
Updates tailscale/corp#17122
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Co-authored-by: Brad Fitzpatrick <bradfitz@tailscale.com>
Change-Id: I06f88c22a1f7ffcbc7ff82946335356bb0ef4622
This actually performs a Noise request in the 'debug ts2021' command,
instead of just exiting once we've dialed a connection. This can help
debug certain forms of captive portals and deep packet inspection that
will allow a connection, but will RST the connection when trying to send
data on the post-upgraded TCP connection.
Updates #1634
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I1e46ca9c9a0751c55f16373a6a76cdc24fec1f18
So that it can be later used in the 'tailscale debug ts2021' function in
the CLI, to aid in debugging captive portals/WAFs/etc.
Updates #1634
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Iec9423f5e7570f2c2c8218d27fc0902137e73909
Previously, we were registering TCP and UDP connections in the same map,
which could result in erroneously removing a mapping if one of the two
connections completes while the other one is still active.
Add a "proto string" argument to these functions to avoid this.
Additionally, take the "proto" argument in LocalAPI, and plumb that
through from the CLI and add a new LocalClient method.
Updates tailscale/corp#20600
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I35d5efaefdfbf4721e315b8ca123f0c8af9125fb
This refactors the logic for determining whether a packet should be sent
to the host or not into a function, and then adds tests for it.
Updates #11304
Updates #12448
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ief9afa98eaffae00e21ceb7db073c61b170355e5
As an alterative to #11935 using #12003.
Updates #11935
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I05f643fe812ceeaec5f266e78e3e529cab3a1ac3
This is a variant of DoChan that supports context propagation, such that
the context provided to the inner function will only be canceled when
there are no more waiters for a given key. This can be used to
deduplicate expensive and cancelable calls among multiple callers
safely.
Updates #11935
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ibe1fb67442a854babbc6924fd8437b02cc9e7bcf
This can be used to implement a persistent pool (i.e. one that isn't
cleared like sync.Pool is) of items–e.g. database connections.
Some benchmarks vs. a naive implementation that uses a single map
iteration show a pretty meaningful improvement:
$ benchstat -col /impl ./bench.txt
goos: darwin
goarch: arm64
pkg: tailscale.com/util/pool
│ Pool │ map │
│ sec/op │ sec/op vs base │
Pool_AddDelete-10 10.56n ± 2% 15.11n ± 1% +42.97% (p=0.000 n=10)
Pool_TakeRandom-10 56.75n ± 4% 1899.50n ± 20% +3246.84% (p=0.000 n=10)
geomean 24.49n 169.4n +591.74%
Updates tailscale/corp#19900
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ie509cb65573c4726cfc3da9a97093e61c216ca18
Without changing behaviour, don't create a goroutine per connection that
sits and sleeps, but rather use a timer that wakes up and gathers
statistics on a regular basis.
Fixes#12127
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ibc486447e403070bdc3c2cd8ae340e7d02854f21
When Docker is detected on the host and stateful filtering is enabled,
Docker containers may be unable to reach Tailscale nodes (depending on
the network settings of a container). Detect Docker when stateful
filtering is enabled and print a health warning to aid users in noticing
this issue.
We avoid printing the warning if the current node isn't advertising any
subnet routes and isn't an exit node, since without one of those being
true, the node wouldn't have the correct AllowedIPs in WireGuard to
allow a Docker container to connect to another Tailscale node anyway.
Updates #12070
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Idef538695f4d101b0ef6f3fb398c0eaafc3ae281
Previously, a node that was advertising a 4via6 route wouldn't be able
to make use of that same route; the packet would be delivered to
Tailscale, but since we weren't accepting it in handleLocalPackets, the
packet wouldn't be delivered to netstack and would never hit the 4via6
logic. Let's add that support so that usage of 4via6 is consistent
regardless of where the connection is initiated from.
Updates #11304
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ic28dc2e58080d76100d73b93360f4698605af7cb
Setting the field after-the-fact wasn't working because we could migrate
prefs on creation, which would set health status for auto updates.
Updates #11986
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I41d79ebd61d64829a3a9e70586ce56f62d24ccfd
To aid in debugging exactly what's going wrong, instead of the
not-particularly-useful "dns udp query: context deadline exceeded" error
that we currently get.
Updates #3786
Updates #10768
Updates #11620
(etc.)
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I76334bf0681a8a2c72c90700f636c4174931432c
So that we can use this for additional, non-NAT configuration without it
being confusing.
Updates #cleanup
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I1658d59c9824217917a94ee76d2d08f0a682986f
This was a holdover from the older, pre-BART days and is no longer
necessary.
Updates #cleanup
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I71b892bab1898077767b9ff51cef33d59c08faf8
Also, reset it in a few more places (e.g. logout, new blank profiles,
etc.) to avoid a few more cases where a pre-existing dialPlan can cause
a new Headscale server take 10+ seconds to connect.
Updates #11938
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I3095173a5a3d9720507afe4452548491e9e45a3e
Since the tailscaled binaries that we distribute are static and don't
link cgo, we previously wouldn't fetch group IDs that are returned via
NSS. Try shelling out to the 'id' command, similar to how we call
'getent', to detect such cases.
Updates #11682
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I9bdc938bd76c71bc130d44a97cc2233064d64799
If this happens, it results in us pessimistically closing more
connections than might be necessary, but is more correct since we won't
"miss" a change to the default route interface and keep trying to send
data over a nonexistent interface, or one that can't reach the internet.
Updates tailscale/corp#19124
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ia0b8b04cb8cdcb0da0155fd08751c9dccba62c1a
This ensures that we close the underlying connection(s) when a major
link change happens. If we don't do this, on mobile platforms switching
between WiFi and cellular can result in leftover connections in the
http.Client's connection pool which are bound to the "wrong" interface.
Updates #10821
Updates tailscale/corp#19124
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ibd51ce2efcaf4bd68e14f6fdeded61d4e99f9a01
This wasn't previously handling the case where an interface in s2 was
removed and not present in s1, and would cause the Equal method to
incorrectly return that the states were equal.
Updates tailscale/corp#19124
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I3af22bc631015d1ddd0a1d01bfdf312161b9532d
So that we can e.g. check TLS on multiple ports for a given IP.
Updates tailscale/corp#16367
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I81d840a4c88138de1cbb2032b917741c009470e6
This allows us to check all IP addresses (and address families) for a
given DNS hostname while dynamically discovering new IPs and removing
old ones as they're no longer valid.
Also add a testable example that demonstrates how to use it.
Alternative to #11610
Updates tailscale/corp#16367
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I6d6f39bafc30e6dfcf6708185d09faee2a374599
This can be used to reload a value periodically, whether from disk or
another source, while handling jitter and graceful shutdown.
Updates tailscale/corp#1297
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Iee2b4385c9abae59805f642a7308837877cb5b3f
To mimic sync.Map.Swap, sync/atomic.Value.Swap, etc.
Updates tailscale/corp#1297
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: If7627da1bce8b552873b21d7e5ebb98904e9a650
This fixes a bug that was introduced in #11258 where the handling of the
per-client limit didn't properly account for the fact that the gVisor
TCP forwarder will return 'true' to indicate that it's handled a
duplicate SYN packet, but not launch the handler goroutine.
In such a case, we neither decremented our per-client limit in the
wrapper function, nor did we do so in the handler function, leading to
our per-client limit table slowly filling up without bound.
Fix this by doing the same duplicate-tracking logic that the TCP
forwarder does so we can detect such cases and appropriately decrement
our in-flight counter.
Updates tailscale/corp#12184
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ib6011a71d382a10d68c0802593f34b8153d06892
This pretty much always results in an outage because peers won't
discover our new home region and thus won't be able to establish
connectivity.
Updates tailscale/corp#18095
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ic0d09133f198b528dd40c6383b16d7663d9d37a7
So we can use it in trunkd to quiet down the logs there.
Updates #5563
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ie3177dc33f5ad103db832aab5a3e0e4f128f973f
This test could hang because the subprocess was blocked on writing to
the stdout pipe if we find the address we're looking for early in the
output.
Updates #cleanup
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I68d82c22a5d782098187ae6d8577e43063b72573
The `stack.PacketBufferPtr` type no longer exists; replace it with
`*stack.PacketBuffer` instead.
Updates #8043
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ib56ceff09166a042aa3d9b80f50b2aa2d34b3683
In case we want to change the format to something opaque later.
Updates tailscale/corp#2549
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ie2eac8b885b694be607e9d5101d24b650026d89c
Since link-local addresses are definitionally more likely to be a direct
(lower-latency, more reliable) connection than a non-link-local private
address, give those a bit of a boost when selecting endpoints.
Updates #8097
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I93fdeb07de55ba39ba5fcee0834b579ca05c2a4e
This is a fun one. Right now, when a client is connecting through a
subnet router, here's roughly what happens:
1. The client initiates a connection to an IP address behind a subnet
router, and sends a TCP SYN
2. The subnet router gets the SYN packet from netstack, and after
running through acceptTCP, starts DialContext-ing the destination IP,
without accepting the connection¹
3. The client retransmits the SYN packet a few times while the dial is
in progress, until either...
4. The subnet router successfully establishes a connection to the
destination IP and sends the SYN-ACK back to the client, or...
5. The subnet router times out and sends a RST to the client.
6. If the connection was successful, the client ACKs the SYN-ACK it
received, and traffic starts flowing
As a result, the notification code in forwardTCP never notices when a
new connection attempt is aborted, and it will wait until either the
connection is established, or until the OS-level connection timeout is
reached and it aborts.
To mitigate this, add a per-client limit on how many in-flight TCP
forwarding connections can be in-progress; after this, clients will see
a similar behaviour to the global limit, where new connection attempts
are aborted instead of waiting. This prevents a single misbehaving
client from blocking all other clients of a subnet router by ensuring
that it doesn't starve the global limiter.
Also, bump the global limit again to a higher value.
¹ We can't accept the connection before establishing a connection to the
remote server since otherwise we'd be opening the connection and then
immediately closing it, which breaks a bunch of stuff; see #5503 for
more details.
Updates tailscale/corp#12184
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I76e7008ddd497303d75d473f534e32309c8a5144
This fixes an infinite loop caused by the configuration of
systemd-resolved on Amazon Linux 2023 and how that interacts with
Tailscale's "direct" mode. We now drop the Tailscale service IP from the
OS's "base configuration" when we detect this configuration.
Updates #7816
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I73a4ea8e65571eb368c7e179f36af2c049a588ee
This package uses a count-min sketch and a heap to track the top K items
in a stream of data. Tracking a new item and adding a count to an
existing item both require no memory allocations and is at worst
O(log(k)) complexity.
Change-Id: I0553381be3fef2470897e2bd806d43396f2dbb36
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
These are functionally the same as the "urn:schemas-upnp-org" services
with a few minor changes, and are still used by older devices. Support
them to improve our ability to obtain an external IP on such networks.
Updates #10911
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I05501fad9d6f0a3b8cf19fc95eee80e7d16cc2cf
This no longer results in a nil pointer exception when we get a valid
UPnP response with no supported clients.
Updates #10911
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I6e3715a49a193ff5261013871ad7fff197a4d77e
When tailscaled is run with "-debug 127.0.0.1:12345", these metrics are
available at:
http://localhost:12345/debug/metrics
Updates #8210
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I19db6c445ac1f8344df2bc1066a3d9c9030606f8
For use in corp, where we appear to have re-implemented this in a few
places with varying signatures.
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Id863a87e674f3caa87945519be8e09650e9c1d76
This is in response to logs from a customer that show that we're unable
to run netsh due to the following error:
router: firewall: adding Tailscale-Process rule to allow UDP for "C:\\Program Files\\Tailscale\\tailscaled.exe" ...
router: firewall: error adding Tailscale-Process rule: exec: "netsh": cannot run executable found relative to current directory:
There's approximately no reason to ever dynamically look up the path of
a system utility like netsh.exe, so instead let's first look for it
in the System32 directory and only if that fails fall back to the
previous behaviour.
Updates #10804
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I68cfeb4cab091c79ccff3187d35f50359a690573
The prefix has space for 32-bit site IDs, but the validateViaPrefix
function would previously have disallowed site IDs greater than 255.
Fixestailscale/corp#16470
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I4cdb0711dafb577fae72d86c4014cf623fa538ef
To make it easier to correlate the starting/ending log messages.
Updates #cleanup
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I2802d53ad98e19bc8914bc58f8c04d4443227b26
This command allows observing whether a given dialer ("SystemDial",
"UserDial", etc.) will successfully obtain a connection to a provided
host, from inside tailscaled itself. This is intended to help debug a
variety of issues from subnet routers to split DNS setups.
Updates #9619
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ie01ebb5469d3e287eac633ff656783960f697b84
This tripped me up when I was testing something and wrote:
if conn != nil {
conn.Close()
}
In netstack mode, when an error occurred we were getting a non-nil error
and a non-nil interface that contained a nil pointer. Instead, just
return a nil interface value.
Updates #cleanup
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Id9ef3dd24529e0e8c53adc60ed914c31fbb10cc4
If the epoch that we see during a Probe is less than the existing epoch,
it means that the gateway has either restarted or reset its
configuration, and an existing mapping is no longer valid. Reset any
saved mapping(s) if we detect this case so that a future
createOrGetMapping will not attempt to re-use it.
Updates #10597
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ie3cddaf625cb94a29885f7a1eeea25dbf6b97b47
This logs additional information about what mapping(s) are obtained
during the creation process, including whether we return an existing
cached mapping.
Updates #10597
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I9ff25071f064c91691db9ab0b9365ccc5f948d6e
Currently, we get the "likely home router" gateway IP and then iterate
through all IPs for all interfaces trying to match IPs to determine the
source IP. However, on many platforms we know what interface the gateway
is through, and thus we don't need to iterate through all interfaces
checking IPs. Instead, use the IP address of the associated interface.
This better handles the case where we have multiple interfaces on a
system all connected to the same gateway, and where the first interface
that we visit (as iterated by ForeachInterfaceAddress) isn't also the
default internet route.
Updates #8992
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I8632f577f1136930f4ec60c76376527a19a47d1f
The cmpx.Compare function (and associated interface) are now available
in the standard library as cmp.Compare. Remove our version of it and use
the version from the standard library.
Updates #cleanup
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I4be3ac63d466c05eb7a0babb25cb0d41816fbd53
Instead of taking the first UPnP response we receive and using that to
create port mappings, store all received UPnP responses, sort and
deduplicate them, and then try all of them to obtain an external
address.
Updates #10602
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I783ccb1834834ee2a9ecbae2b16d801f2354302f
This uses the fact that we've received a frame from a given DERP region
within a certain time as a signal that the region is stil present (and
thus can still be a node's PreferredDERP / home region) even if we don't
get a STUN response from that region during a netcheck.
This should help avoid DERP flaps that occur due to losing STUN probes
while still having a valid and active TCP connection to the DERP server.
RELNOTE=Reduce home DERP flapping when there's still an active connection
Updates #8603
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: If7da6312581e1d434d5c0811697319c621e187a0
Previously, we would select the first WANIPConnection2 (and related)
client from the root device, without any additional checks. However,
some routers expose multiple UPnP devices in various states, and simply
picking the first available one can result in attempting to perform a
portmap with a device that isn't functional.
Instead, mimic what the miniupnpc code does, and prefer devices that are
(a) reporting as Connected, and (b) have a valid external IP address.
For our use-case, we additionally prefer devices that have an external
IP address that's a public address, to increase the likelihood that we
can obtain a direct connection from peers.
Finally, we split out fetching the root device (getUPnPRootDevice) from
selecting the best service within that root device (selectBestService),
and add some extensive tests for various UPnP server behaviours.
RELNOTE=Improve UPnP portmapping when multiple UPnP services exist
Updates #8364
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I71795cd80be6214dfcef0fe83115a5e3fe4b8753
This package allows caching arbitrary key/value pairs in-memory, along
with an interface implemented by the cache types.
Extracted from #7493
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Ic8ca820927c456721cf324a0c8f3882a57752cc9
Before this fix, LikelyHomeRouterIP could return a 'self' IP that
doesn't correspond to the gateway address, since it picks the first
private address when iterating over the set interfaces as the 'self' IP,
without checking that the address corresponds with the
previously-detected gateway.
This behaviour was introduced by accident in aaf2df7, where we deleted
the following code:
for _, prefix := range privatev4s {
if prefix.Contains(gateway) && prefix.Contains(ip) {
myIP = ip
ok = true
return
}
}
Other than checking that 'gateway' and 'ip' were private IP addresses
(which were correctly replaced with a call to the netip.Addr.IsPrivate
method), it also implicitly checked that both 'gateway' and 'ip' were a
part of the *same* prefix, and thus likely to be the same interface.
Restore that behaviour by explicitly checking pfx.Contains(gateway),
which, given that the 'ip' variable is derived from our prefix 'pfx',
ensures that the 'self' IP will correspond to the returned 'gateway'.
Fixes#10466
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: Iddd2ee70cefb9fb40071986fefeace9ca2441ee6
This prevents running more than one recursive resolution for the same
hostname in parallel, which can use excessive amounts of CPU when called
in a tight loop. Additionally, add tests that hit the network (when
run with a flag) to test the lookup behaviour.
Updates tailscale/corp#15261
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
Change-Id: I39351e1d2a8782dd4c52cb04b3bd982eb651c81e
Andrew Dunham
