Commit Graph

706 Commits (e36c27bcd1237272526f1a5b28cd587b575acaa1)

Author SHA1 Message Date
Brad Fitzpatrick 0d52674a84 net/tstun: diagnose /dev/net/tun fd leak, give better failure message
Updates #5029

Change-Id: Ibee5e0c9076fe764eb5d856d5ef8b09f4d0e2921
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Andrew Dunham c7993d2b88
net/dns/resolver: add fuzz/unit test for #2533 (#5018)
Signed-off-by: Andrew Dunham <andrew@du.nham.ca>
2 years ago
Tom DNetto d6817d0f22 net/dns/resolver: respond with SERVFAIL if all upstreams fail
Fixes #4722

Signed-off-by: Tom DNetto <tom@tailscale.com>
2 years ago
Mihai Parparita ec649e707f ipn/ipnlocal: prefer to use one CGNAT route on the Mac
Together with 06aa141632 this minimizes
the number of NEPacketTunnelNetworkSettings updates that we have to do,
and thus avoids Chrome interrupting outstanding requests due to
(perceived) network changes.

Updates #3102

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Brad Fitzpatrick aa37aece9c ipn/ipnlocal, net/dns*, util/cloudenv: add AWS DNS support
And remove the GCP special-casing from ipn/ipnlocal; do it only in the
forwarder for *.internal.

Fixes #4980
Fixes #4981

Change-Id: I5c481e96d91f3d51d274a80fbd37c38f16dfa5cb
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Brad Fitzpatrick 88c2afd1e3 ipn/ipnlocal, net/dns*, util/cloudenv: specialize DNS config on Google Cloud
This does three things:

* If you're on GCP, it adds a *.internal DNS split route to the
  metadata server, so we never break GCP DNS names. This lets people
  have some Tailscale nodes on GCP and some not (e.g. laptops at home)
  without having to add a Tailnet-wide *.internal DNS route.
  If you already have such a route, though, it won't overwrite it.

* If the 100.100.100.100 DNS forwarder has nowhere to forward to,
  it forwards it to the GCP metadata IP, which forwards to 8.8.8.8.
  This means there are never errNoUpstreams ("upstream nameservers not set")
  errors on GCP due to e.g. mangled /etc/resolv.conf (GCP default VMs
  don't have systemd-resolved, so it's likely a DNS supremacy fight)

* makes the DNS fallback mechanism use the GCP metadata IP as a
  fallback before our hosted HTTP-based fallbacks

I created a default GCP VM from their web wizard. It has no
systemd-resolved.

I then made its /etc/resolv.conf be empty and deleted its GCP
hostnames in /etc/hosts.

I then logged in to a tailnet with no global DNS settings.

With this, tailscaled writes /etc/resolv.conf (direct mode, as no
systemd-resolved) and sets it to 100.100.100.100, which then has
regular DNS via the metadata IP and *.internal DNS via the metadata IP
as well. If the tailnet configures explicit DNS servers, those are used
instead, except for *.internal.

This also adds a new util/cloudenv package based on version/distro
where the cloud type is only detected once. We'll likely expand it in
the future for other clouds, doing variants of this change for other
popular cloud environments.

Fixes #4911

RELNOTES=Google Cloud DNS improvements

Change-Id: I19f3c2075983669b2b2c0f29a548da8de373c7cf
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Denton Gentry d7f452c0a1 net/portmapper: send discovery packet for IGD specifically.
There appear to be devices out there which send only their
first descriptor in response to a discovery packet for
`ssdp:all`, for example the Sagemcom FAST3890V3 only sends
urn:schemas-wifialliance-org:device:WFADevice:1

Send both ssdp:all and a discovery frame for
InternetGatewayDevice specifically.

Updates https://github.com/tailscale/tailscale/issues/3557

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Denton Gentry 09eaba91ad net/portmap: add a test for Sagemcom FAST3890V3.
Updates https://github.com/tailscale/tailscale/issues/3557

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Denton Gentry b5553c6ad2 net/portmap: run go fmt
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Denton Gentry de4c635e54 net/portmapper: make pcpCodeNotAuthorized log more descriptive
If PCP is present but disabled, turning it on might help
get direct connections.

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Aaron Klotz 4baf34cf25 net/dns: set appropriate Windows registry values to prevent it from sending DNS changes concerning our interface to AD domain controllers.
We do this unconditionally inside SetDNS such that the values are always set
before we make any other changes to DNS configurations.

It should not be harmful for the settings to remain even when other DNS
settings are cleared out (since they only affect our network interface).

See https://docs.microsoft.com/en-us/troubleshoot/windows-server/networking/configure-dns-dynamic-updates-windows-server-2003 for details about the registry value.

Fixes https://github.com/tailscale/tailscale/issues/4829

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2 years ago
Aaron Klotz 8cdfd12977 net/dns: update Windows split DNS settings to work alongside other NRPT entries set by group policy.
When there are group policy entries for the NRPT that do not belong to Tailscale,
we recognize that we need to add ourselves to group policy and use that registry
key instead of the local one. We also refresh the group policy settings as
necessary to ensure that our changes take effect immediately.

Fixes https://github.com/tailscale/tailscale/issues/4607

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2 years ago
Brad Fitzpatrick 13d0b8e6a4 control/controlclient, net/dnscache: use typed singleflight fork
Change-Id: I12be4c5a91ae3a812fe88d9b2d15526fdbb5a921
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Denton Gentry 1392a93445 socks5: add a simple test
Start up a backend service, put a SOCKS5 server in front
of it, and verify that we can get data from the backend via
SOCKS5.

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Denton Gentry 7fffddce8e net/portmapper: enable for iOS
In the 1.27 unstable releases we set the min-version to iOS15,
which means we have 50 MBytes of RAM in the Network Extension.
https://tailscale.com/blog/go-linker/

Include the UPnP/NAT-PMP/PCP portmapper support now that there
is memory for it.

Fixes https://github.com/tailscale/tailscale/issues/2495
Signed-off-by: Denton Gentry <dgentry@tailscale.com>
2 years ago
Mihai Parparita edc90ebc61 net/wsconn: remove homegrown wrapper for turning a websocket.Conn into a net.Conn
The one from the nhooyr/websocket package seems to work equally well.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Mihai Parparita 27a1ad6a70
wasm: exclude code that's not used on iOS for Wasm too
It has similar size constraints. Saves ~1.9MB from the Wasm build.

Updates #3157

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Mihai Parparita a9f32656f5 control/controlhttp: allow client and server to communicate over WebSockets
We can't do Noise-over-HTTP in Wasm/JS (because we don't have bidirectional
communication), but we should be able to do it over WebSockets. Reuses
derp WebSocket support that allows us to turn a WebSocket connection
into a net.Conn.

Updates #3157

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
2 years ago
Maisem Ali 80157f3f37 net/dns/resolver: add support for <IPv4>.via-<site-id>
Currently we only support "via-<site-id>.<IPv4>", however that does not
work with Google Chrome which parses `http://via-1.10.0.0.1` as a search
string and not as a URL. This commit introduces "<IPv4>.via-<site-id>"
(`http://10.0.0.1.via-1`) which is parsed correctly by Chrome.

Updates #3616

Signed-off-by: Maisem Ali <maisem@tailscale.com>
2 years ago
Brad Fitzpatrick 1336fb740b wgengine/netstack: make netstack MTU be 1280 also
Updates #3878

Change-Id: I1850085b32c8a40d85607b4ad433622c97d96a8d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
2 years ago
Aaron Klotz b005b79236 net/dns, paths, util/winutil: change net/dns/windowsManager NRPT management to support more than 50 domains.
AFAICT this isn't documented on MSDN, but based on the issue referenced below,
NRPT rules are not working when a rule specifies > 50 domains.

This patch modifies our NRPT rule generator to split the list of domains
into chunks as necessary, and write a separate rule for each chunk.

For compatibility reasons, we continue to use the hard-coded rule ID, but
as additional rules are required, we generate new GUIDs. Those GUIDs are
stored under the Tailscale registry path so that we know which rules are ours.

I made some changes to winutils to add additional helper functions in support
of both the code and its test: I added additional registry accessors, and also
moved some token accessors from paths to util/winutil.

Fixes https://github.com/tailscale/coral/issues/63

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
2 years ago
Tom acfe5bd33b
net/dns{., resolver}: time out DNS queries after 10 seconds (#4690)
Fixes https://github.com/tailscale/corp/issues/5198

The upstream forwarder will block indefinitely on `udpconn.ReadFrom` if no
reply is recieved, due to the lack of deadline on the connection object.

There still isn't a deadline on the connection object, but the automatic closing
of the context on deadline expiry will close the connection via `closeOnCtxDone`,
unblocking the read and resulting in a normal teardown.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Mihai Parparita 86069874c9 net/tstun, wgengine: use correct type for counter metrics
We were marking them as gauges, but they are only ever incremented,
thus counter is more appropriate.

Signed-off-by: Mihai Parparita <mihai@tailscale.com>
3 years ago
Maisem Ali fd99c54e10 tailcfg,all: change structs to []*dnstype.Resolver
Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
Tom d1d6ab068e
net/dns, wgengine: implement DNS over TCP (#4598)
* net/dns, wgengine: implement DNS over TCP

Signed-off-by: Tom DNetto <tom@tailscale.com>

* wgengine/netstack: intercept only relevant port/protocols to quad-100

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
James Tucker f9e86e64b7 *: use WireGuard where logged, printed or named
Signed-off-by: James Tucker <james@tailscale.com>
3 years ago
James Tucker ae483d3446 wgengine, net/packet, cmd/tailscale: add ICMP echo
Updates tailscale/corp#754

Signed-off-by: James Tucker <james@tailscale.com>
3 years ago
Tom DNetto 2a0b5c21d2 net/dns/{., resolver}, wgengine: fix goroutine leak on shutdown
Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Tom DNetto 7f45734663 assorted: documentation and readability fixes
This were intended to be pushed to #4408, but in my excitement I
forgot to git push :/ better late than never.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Tom DNetto 9e77660931 net/tstun,wgengine/{.,netstack}: handle UDP magicDNS traffic in netstack
This change wires netstack with a hook for traffic coming from the host
into the tun, allowing interception and handling of traffic to quad-100.

With this hook wired, magicDNS queries over UDP are now handled within
netstack. The existing logic in wgengine to handle magicDNS remains for now,
but its hook operates after the netstack hook so the netstack implementation
takes precedence. This is done in case we need to support platforms with
netstack longer than expected.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Tom DNetto dc71d3559f net/tstun,wgengine: split PreFilterOut into multiple hooks
A subsequent commit implements handling of magicDNS traffic via netstack.
Implementing this requires a hook for traffic originating from the host and
hitting the tun, so we make another hook to support this.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Tom DNetto 5b85f848dd net/dns,net/dns/resolver: refactor channels/magicDNS out of Resolver
Moves magicDNS-specific handling out of Resolver & into dns.Manager. This
greatly simplifies the Resolver to solely issuing queries and returning
responses, without channels.

Enforcement of max number of in-flight magicDNS queries, assembly of
synthetic UDP datagrams, and integration with wgengine for
recieving/responding to magicDNS traffic is now entirely in Manager.
This path is being kept around, but ultimately aims to be deleted and
replaced with a netstack-based path.

This commit is part of a series to implement magicDNS using netstack.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Brad Fitzpatrick 6bed781259 all: gofmt all
Well, goimports actually (which adds the normal import grouping order we do)

Change-Id: I0ce1b1c03185f3741aad67c14a7ec91a838de389
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
James Tucker 96fec4b969 net/tshttpproxy: synology: pick proxy by scheme
This updates the fix from #4562 to pick the proxy based on the request
scheme.

Updates #4395, #2605, #4562
Signed-off-by: James Tucker <james@tailscale.com>
3 years ago
Maisem Ali eff6a404a6 net/tshttpproxy: use http as the scheme for proxies
Currently we try to use `https://` when we see `https_host`, however
that doesn't work and results in errors like `Received error: fetch
control key: Get "https://controlplane.tailscale.com/key?v=32":
proxyconnect tcp: tls: first record does not look like a TLS handshake`

This indiciates that we are trying to do a HTTPS request to a HTTP
server. Googling suggests that the standard is to use `http` regardless
of `https` or `http` proxy

Updates #4395, #2605

Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
Maisem Ali 5a1ef1bbb9 net/tsdial: add SystemDial as a wrapper on netns.Dial
The connections returned from SystemDial are automatically closed when
there is a major link change.

Also plumb through the dialer to the noise client so that connections
are auto-reset when moving from cellular to WiFi etc.

Updates #3363

Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
Brad Fitzpatrick c6c752cf64 net/tshttpproxy: fix typo
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Tom DNetto 5fb8e01a8b net/dns/resolver: add metric for number of truncated dns packets
Updates #2067

This should help us determine if more robust control of edns parameters
+ implementing answer truncation is warranted, given its likely complexity.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Brad Fitzpatrick e97209c6bf net/dns: add tailscaled-on-macOS DNS OSConfigurator
This populates DNS suffixes ("ts.net", etc) in /etc/resolver/* files
to point to 100.100.100.100 so MagicDNS works.

It also sets search domains.

Updates #4276

Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Tom DNetto 78fededaa5 net/dns/resolver: support magic resolution of via-<siteid>.<ip4> domains
Updates #3616

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
James Tucker 700bd37730 tshttpproxy: support synology proxy configuration
Fixes #4395
Fixes #2605

Signed-off-by: James Tucker <james@tailscale.com>
3 years ago
Tom DNetto df26c63793 net/dns/resolver, net/tsaddr: fix reverse lookups in 4to6 IP range
Fixes #4439

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Brad Fitzpatrick d413850bd7 cmd/tailscale: add "debug via" subcommand to do CIDR math for via ranges
$ tailscale debug via 0xb 10.2.0.0/16
fd7a:115c:a1e0:b1a:0🅱️a02:0/112
$ tailscale debug via fd7a:115c:a1e0:b1a:0🅱️a02:0/112
site 11 (0xb), 10.2.0.0/16

Previously: 3ae701f0eb

This adds a little debug tool to do CIDR math to make converting between
those ranges easier for now.

Updates #3616

Change-Id: I98302e95d17765bfaced3ecbb71cbd43e84bff46
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Tom DNetto c8f4dfc8c0 derp/derphttp,net/netcheck: improve netcheck behavior under MITM proxies
In cases where tailscale is operating behind a MITM proxy, we need to consider
that a lot more of the internals of our HTTP requests are visible and may be
used as part of authorization checks. As such, we need to 'behave' as closely
as possible to ideal.

 - Some proxies do authorization or consistency checks based the on Host header
   or HTTP URI, instead of just the IP/hostname/SNI. As such, we need to
   construct a `*http.Request` with a valid URI everytime HTTP is going to be
   used on the wire, even if its over TLS.
   Aside from the singular instance in net/netcheck, I couldn't find anywhere
   else a http.Request was constructed incorrectly.

 - Some proxies may deny requests, typically by returning a 403 status code. We
   should not consider these requests as a valid latency check, so netcheck
   semantics have been updated to consider >299 status codes as a failed probe.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Brad Fitzpatrick cc575fe4d6 net/dns: schedule DoH upgrade explicitly, fix Resolver.Addr confusion
Two changes in one:

* make DoH upgrades an explicitly scheduled send earlier, when we come
  up with the resolvers-and-delay send plan. Previously we were
  getting e.g.  four Google DNS IPs and then spreading them out in
  time (for back when we only did UDP) but then later we added DoH
  upgrading at the UDP packet layer, which resulted in sometimes
  multiple DoH queries to the same provider running (each doing happy
  eyeballs dialing to 4x IPs themselves) for each of the 4 source IPs.
  Instead, take those 4 Google/Cloudflare IPs and schedule 5 things:
  first the DoH query (which can use all 4 IPs), and then each of the
  4 IPs as UDP later.

* clean up the dnstype.Resolver.Addr confusion; half the code was
  using it as an IP string (as documented) as half was using it as
  an IP:port (from some prior type we used), primarily for tests.
  Instead, document it was being primarily an IP string but also
  accepting an IP:port for tests, then add an accessor method on it
  to get the IPPort and use that consistently everywhere.

Change-Id: Ifdd72b9e45433a5b9c029194d50db2b9f9217b53
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick e3a4952527 net/dns/resolver: count errors when racing DNS queries, fail earlier
If all N queries failed, we waited until context timeout (in 5
seconds) to return.

This makes (*forwarder).forward fail fast when the network's
unavailable.

Change-Id: Ibbb3efea7ed34acd3f3b29b5fee00ba8c7492569
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick d9efbd97cb net/dns: remove an unused function
Change-Id: I7c920c76223ffac37954ef2a18754afc52177598
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick ecea6cb994 net/dns/resolver: make DoH dialer use existing dnscache happy eyeball dialer
Simplify the ability to reason about the DoH dialing code by reusing the
dnscache's dialer we already have.

Also, reduce the scope of the "ip" variable we don't want to close over.

This necessarily adds a new field to dnscache.Resolver:
SingleHostStaticResult, for when the caller already knows the IPs to be
returned.

Change-Id: I9f2aef7926f649137a5a3e63eebad6a3fffa48c0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick f4f76eb275 net/dnsfallback: update from 'go generate'
Change-Id: I93e0e6d9a4a471953c1ffef07f32605c5724aed8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
phirework 52d32c94d8
net/dns/publicdns: add missing call to sync.Once.Do (#4410)
Signed-off-by: Jenny Zhang <jz@tailscale.com>
3 years ago
phirework 83c734a6e0
net/dns, util/publicdns: extract public DNS mapping into own package (#4405)
This extracts DOH mapping of known public DNS providers in
forwarder.go into its own package, to be consumed by other repos

Signed-off-by: Jenny Zhang <jz@tailscale.com>
3 years ago
Brad Fitzpatrick a49d8d5200 Revert ".github/workflows: work around golang/go#51629"
This reverts commit 2a412ac9ee.

Updates #4194

Change-Id: I0098b66b71d20bea301ca79058c1cdd201237dd0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 3ae701f0eb net/tsaddr, wgengine/netstack: add IPv6 range that forwards to site-relative IPv4
This defines a new magic IPv6 prefix, fd7a:115c:a1e0:b1a::/64, a
subset of our existing /48, where the final 32 bits are an IPv4
address, and the middle 32 bits are a user-chosen "site ID". (which
must currently be 0000:00xx; the top 3 bytes must be zero for now)

e.g., I can say my home LAN's "site ID" is "0000:00bb" and then
advertise its 10.2.0.0/16 IPv4 range via IPv6, like:

    tailscale up --advertise-routes=fd7a:115c:a1e0:b1a::bb:10.2.0.0/112

(112 being /128 minuse the /96 v6 prefix length)

Then people in my tailnet can:

     $ curl '[fd7a:115c:a1e0:b1a::bb:10.2.0.230]'
     <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" ....

Updates #3616, etc

RELNOTE=initial support for TS IPv6 addresses to route v4 "via" specific nodes

Change-Id: I9b49b6ad10410a24b5866b9fbc69d3cae1f600ef
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Tom 24bdcbe5c7
net/dns, net/dns/resolver, wgengine: refactor DNS request path (#4364)
* net/dns, net/dns/resolver, wgengine: refactor DNS request path

Previously, method calls into the DNS manager/resolver types handled DNS
requests rather than DNS packets. This is fine for UDP as one packet
corresponds to one request or response, however will not suit an
implementation that supports DNS over TCP.

To support PRs implementing this in the future, wgengine delegates
all handling/construction of packets to the magic DNS endpoint, to
the DNS types themselves. Handling IP packets at this level enables
future support for both UDP and TCP.

Signed-off-by: Tom DNetto <tom@tailscale.com>
3 years ago
Tom 6be7931eb4
net/dns/resolver: return symbolic PTR records for TS service IPs (#4361)
Fixes #1233

Signed-off-by: Tom DNetto <tom@tailscale.com>

Co-authored-by: Tom DNetto <tom@tailscale.com>
3 years ago
Maisem Ali 309ddef852
net/netutil: add CheckIPForwardingLinux (#4301)
Combine the code between `LocalBackend.CheckIPForwarding` and
`controlclient.ipForwardingBroken`.

Fixes #4300

Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
Brad Fitzpatrick e4d8d5e78b net/packet, wgengine/netstack: remove workaround for old gvisor ECN bug
Fixes #2642

Change-Id: Ic02251d24a4109679645d1c8336e0f961d0cce13
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 753f1bfad4 cmd/tailscale: write fewer known_hosts, resolve ssh host to FQDN early
Updates #3802

Change-Id: Ic44fa2e6661a9c046e725c04fa6b8213d3d4d2b2
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Maisem Ali b2f269d5b7 net/dnsfallback: do not attempt lookups of IPs.
Currently if the passed in host is an IP, Lookup still attempts to
resolve it with a dns server. This makes it just return the IP directly.

Updates tailscale/corp#4475

Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
Maisem Ali b45bb577a0 net/dnscache: do not call LookupIPFallback if the context was canceled.
When the context is canceled, dc.dialOne returns an error from line 345.
This causes the defer on line 312 to try to resolve the host again, which
triggers a dns lookup of "127.0.0.1" from derp.

Updates tailscale/corp#4475

Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
Brad Fitzpatrick b647977b33 net/netutil: move some net utils from control/controlhttp to netutil
In prep for reuse elsewhere.

Change-Id: I1b804edf76ac66b9108e6f434e77eab7a7472d69
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
James Tucker 445c04c938
wgengine: inject packetbuffers rather than bytes (#4220)
Plumb the outbound injection path to allow passing netstack
PacketBuffers down to the tun Read, where they are decref'd to enable
buffer re-use. This removes one packet alloc & copy, and reduces GC
pressure by pooling outbound injected packets.

Fixes #2741
Signed-off-by: James Tucker <james@tailscale.com>
3 years ago
Brad Fitzpatrick f2041c9088 all: use strings.Cut even more
Change-Id: I943ce72c6f339589235bddbe10d07799c4e37979
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Aaron Klotz 6e91f872af net/tshttpproxy: ensure we pass the correct flags to WinHttpOpen on Win7 and Win8.0
The best flag to use on Win7 and Win8.0 is deprecated in Win8.1, so we resolve
the flag depending on OS version info.

Fixes https://github.com/tailscale/tailscale/issues/4201

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
3 years ago
David Anderson 2a412ac9ee .github/workflows: work around golang/go#51629
Incidentally, simplify the go generate CI workflow, by
marking the dnsfallback update non-hermetic (so CI will
skip it) rather than manually filter it out of `go list`.

Updates #4194

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Josh Bleecher Snyder 0868329936 all: use any instead of interface{}
My favorite part of generics.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick 61ee72940c all: use Go 1.18's strings.Cut
More remain.

Change-Id: I6ec562cc1f687600758deae1c9d7dbd0d04004cb
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Josh Bleecher Snyder 0ef74f37a5 net/dns/resolver: remove closure allocation explanation
As of Go 1.18, the register ABI list includes arm64, amd64,
ppc64, and ppc64le. This is a large enough percentage of the
architectures that it's not worth explaining.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick 61cdcf4082 net/interfaces: add FreeBSD default route lookup (portmapping, etc)
Updates #4101 (probably fixes)

Change-Id: I2b75ee3ced276fb7b211f17c382621cf1ef882fa
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Maisem Ali 2fb087891b net/socks5: always close client connections after serving
Customer reported an issue where the connections were not closing, and
would instead just stay open. This commit makes it so that we close out
the connection regardless of what error we see. I've verified locally
that it fixes the issue, we should add a test for this.

Signed-off-by: Maisem Ali <maisem@tailscale.com>
3 years ago
Brad Fitzpatrick b493ef5b71 net/tsaddr: add func ContainsExitRoutes
Change-Id: I772441a406083e2fe0f9374b2b23d89aac18928f
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 55095df644 net/interfaces: get Linux default route from netlink as fallback
If it's in a non-standard table, as it is on Unifi UDM Pro, apparently.

Updates #4038 (probably fixes, but don't have hardware to verify)

Change-Id: I2cb9a098d8bb07d1a97a6045b686aca31763a937
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Dmytro Shynkevych d9a7205be5 net/tstun: set link speed to SPEED_UNKNOWN
Fixes #3933.

Signed-off-by: Dmytro Shynkevych <dm.shynk@gmail.com>
3 years ago
Brad Fitzpatrick 7d897229d9 net/dns: ignore permission errors on Synology DSM7 for now
Updates #4017

Change-Id: Ia7fd4df47588c010dea8e63d88f397cc8eb748e5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick bb94561c96 net/netutil: fix regression where peerapi would get closed after 1st req
I introduced a bug in 8fe503057d when unifying oneConnListener
implementations.

The NewOneConnListenerFrom API was easy to misuse (its Close method
closes the underlying Listener), and we did (via http.Serve, which
closes the listener after use, which meant we were close the peerapi's
listener, even though we only wanted its Addr)

Instead, combine those two constructors into one and pass in the Addr
explicitly, without delegating through to any Listener.

Change-Id: I061d7e5f842e0cada416e7b2dd62100d4f987125
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 2ff481ff10 net/dns: add health check for particular broken-ish Linux DNS config
Updates #3937 (need to write docs before closing)

Change-Id: I1df7244cfbb0303481e2621ee750d21358bd67c6
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick c988bd6ed1 net/dns/resolvconffile: unify three /etc/resolv.conf parsers into new package
Change-Id: I2120893ca802d12f1bd0407d49077d3672627d33
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 8d6cf14456 net/dnscache: don't do bootstrap DNS lookup after most failed dials
If we've already connected to a certain name's IP in the past, don't
assume the problem was DNS related. That just puts unnecessarily load
on our bootstrap DNS servers during regular restarts of Tailscale
infrastructure components.

Also, if we do do a bootstrap DNS lookup and it gives the same IP(s)
that we already tried, don't try them again.

Change-Id: I743e8991a7f957381b8e4c1508b8e9d0df1782fe
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 903988b392 net/dnscache: refactor from func-y closure-y state to types & methods
No behavior changes (intended, at least).

This is in prep for future changes to this package, which would get
too complicated in the current style.

Change-Id: Ic260f8e34ae2f64f34819d4a56e38bee8d8ac5ce
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 8267ea0f80 net/tstun: remove TODO that's done
This TODO was both added and fixed in 506c727e3.

As I recall, I wasn't originally going to do it because it seemed
annoying, so I wrote the TODO, but then I felt bad about it and just
did it, but forgot to remove the TODO.

Change-Id: I8f3514809ad69b447c62bfeb0a703678c1aec9a3
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 8fe503057d net/netutil: unify two oneConnListeners into a new package
I was about to add a third copy, so unify them now instead.

Change-Id: I3b93896aa1249b1250a6b1df4829d57717f2311a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 21358cf2f5 net/dns: slightly optimize dbusPing for non-dbus case [Linux]
Avoid some work when D-Bus isn't running.

Change-Id: I6f89bb75fdb24c13f61be9b400610772756db1ef
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 37e7a387ff net/dns: remove some unused code for detecting systemd-resolved [Linux]
Change-Id: I19c5fd2cdacfb9e5b688ccd9b4336ae4edffc445
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 15599323a1 net/dns: fix systemd-resolved detection race at boot
If systemd-resolved is enabled but not running (or not yet running,
such as early boot) and resolv.conf is old/dangling, we weren't
detecting systemd-resolved.

This moves its ping earlier, which will trigger it to start up and
write its file.

Updates #3362 (likely fixes)
Updates #3531 (likely fixes)

Change-Id: I6392944ac59f600571c43b8f7a677df224f2beed
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Denton Gentry dbea8217ac net/dns: add NetworkManager regression test
Use the exact /etc/resolv.conf file from a user report.
Updates https://github.com/tailscale/tailscale/issues/3531

Signed-off-by: Denton Gentry <dgentry@tailscale.com>
3 years ago
Brad Fitzpatrick 2a67beaacf net/interfaces: bound Linux /proc/net/route parsing
tailscaled was using 100% CPU on a machine with ~1M lines, 100MB+
of /proc/net/route data.

Two problems: in likelyHomeRouterIPLinux, we didn't stop reading the
file once we found the default route (which is on the first non-header
line when present). Which meant it was finding the answer and then
parsing 100MB over 1M lines unnecessarily. Second was that if the
default route isn't present, it'd read to the end of the file looking
for it. If it's not in the first 1,000 lines, it ain't coming, or at
least isn't worth having. (it's only used for discovering a potential
UPnP/PMP/PCP server, which is very unlikely to be present in the
environment of a machine with a ton of routes)

Change-Id: I2c4a291ab7f26aedc13885d79237b8f05c2fd8e4
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Aaron Bieber e5cd765e00 net/dns/resolvd: properly handle not having "search" entries
This prevents adding an empty "search" line when no search domains are set.

Signed-off-by: Aaron Bieber <aaron@bolddaemon.com>
3 years ago
Brad Fitzpatrick 1af26222b6 go.mod: bump netstack, switch to upstream netstack
Now that Go 1.17 has module graph pruning
(https://go.dev/doc/go1.17#go-command), we should be able to use
upstream netstack without breaking our private repo's build
that then depends on the tailscale.com Go module.

This is that experiment.

Updates #1518 (the original bug to break out netstack to own module)
Updates #2642 (this updates netstack, but doesn't remove workaround)

Change-Id: I27a252c74a517053462e5250db09f379de8ac8ff
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 41fd4eab5c envknob: add new package for all the strconv.ParseBool(os.Getenv(..))
A new package can also later record/report which knobs are checked and
set. It also makes the code cleaner & easier to grep for env knobs.

Change-Id: Id8a123ab7539f1fadbd27e0cbeac79c2e4f09751
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 6feb8f4c51 net/dns: log why resolved does not look like it's on use [Linux]
Updates #3742
Updates #3531

Change-Id: I9fc7fa0f4bcab1cf8001ba92408c660a5b25f105
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Aaron Bieber 411c6c316c net/dns/resolvd: store nameservers
Currently only search domains are stored. This was an oversight
(under?) on my part.

As things are now, when MagicDNS is on and "Override local DNS" is
off, the dns forwarder has to timeout before names resolve. This
introduces a pretty annoying lang that makes everything feel
extremely slow. You will also see an error: "upstream nameservers
not set".

I tested with "Override local DNS" on and off. In both situations
things seem to function as expected (and quickly).

Signed-off-by: Aaron Bieber <aaron@bolddaemon.com>
3 years ago
Brad Fitzpatrick c64af5e676 wgengine/netstack: clear TCP ECN bits before giving to gvisor
Updates #2642

Change-Id: Ic219442a2656dd9dc99ae1dd91e907fd3d924987
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 390490e7b1 net/packet: fix typo in comment
Change-Id: Ia666609fde18db44bf38d4e656f490fc372ac3b6
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Anderson 463b3e8f62 net/dnscache: use tls.Conn.HandshakeContext.
Go 1.17 added a HandshakeContext func to take care of timeouts during
TLS handshaking, so switch from our homegrown goroutine implementation
to the standard way.

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson a9da6b73a8 net/dnscache: don't cancel the TLS context before writing to the result channel.
Cancelling the context makes the timeout goroutine race with the write that
reports a successful TLS handshake, so you can end up with a successful TLS
handshake that mysteriously reports that it timed out after ~0s in flight.

The context is always canceled and cleaned up as the function exits, which
happens mere microseconds later, so just let function exit clean up and
thereby avoid races.

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Brad Fitzpatrick 24a04d07d1 net/dns/resolver: handle tabs as whitespace when ExitDNS parses resolv.conf
On Synology, the /etc/resolv.conf has tabs in it, which this
resolv.conf parser (we have two, sigh) didn't handle.

Updates #3710

Change-Id: I86f8e09ad1867ee32fa211e85c382a27191418ea
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 51bc9a6d9d net/netns: remove a useless probe of the "ip" command
We stopped using it in 1.18.

Change-Id: If5adf1d99275286a89e2a05f0bce5193d9f6e5e3
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 8df3fa4638 net/dns: make WSL network configuration opt-in for now
Tailscale seems to be breaking WSL configurations lately.  Until we
understand what changed, turn off Tailscale's involvement by default
and make it opt-in.

Updates #2815

Change-Id: I9977801f8debec7d489d97761f74000a4a33f71b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Aaron Bieber 189f359609
net/dns: teach OpenBSD's manager to talk to resolvd(8). (#2789)
OpenBSD 6.9 and up has a daemon which handles nameserver configuration. This PR
teaches the OpenBSD dns manager to check if resolvd is being used. If it is, it
will use the route(8) command to tell resolvd to add the Tailscale dns entries
to resolv.conf

Signed-off-by: Aaron Bieber <aaron@bolddaemon.com>
3 years ago
Brad Fitzpatrick 8d0ed1c9ba net/dns/resolver: on Android, make ExitDNS use net package for DNS
Like Windows.

Updates #1738

Change-Id: I9f26bc58ce7e760c749786fbe5d9952c99eeb91c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 506c727e30 ipnlocal, net/{dns,tsaddr,tstun}, wgengine: support MagicDNS on IPv6
Fixes #3660

RELNOTE=MagicDNS now works over IPv6 when CGNAT IPv4 is disabled.

Change-Id: I001e983df5feeb65289abe5012dedd177b841b45
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 2513d2d728 net/{neterror,dns/resolver}: move PacketWasTruncated to neterror from DNS code
And delete the unused code in net/dns/resolver/neterr_*.go.

Change-Id: Ibe62c486bacce2733eb9968c96a98cbbdb2758bd
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 7d9b1de3aa netcheck,portmapper,magicsock: ignore some UDP write errors on Linux
Treat UDP send EPERM errors as a lost UDP packet, not something super
fatal. That's just the Linux firewall preventing it from going out.

And add a leaf package net/neterror for that (and future) policy that
all three packages can share, with tests.

Updates #3619

Change-Id: Ibdb838c43ee9efe70f4f25f7fc7fdf4607ba9c1d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 2c94e3c4ad wgengine/magicsock: don't unconditionally close DERP connections on rebind
Only if the source address isn't on the currently active interface or
a ping of the DERP server fails.

Updates #3619

Change-Id: I6bf06503cff4d781f518b437c8744ac29577acc8
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 04c2c5bd80 net/interfaces: define DefaultRouteInterface and State.DefaultRouteInterface
It was pretty ill-defined before and mostly for logging. But I wanted
to start depending on it, so define what it is and make Windows match
the other operating systems, without losing the log output we had
before. (and add tests for that)

Change-Id: I0fbbba1cfc67a265d09dd6cb738b73f0f6005247
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick eb26c081b1 net/dns: bound time we wait on restarting systemd-resolved in another place
Fixes #3629
Updates #3537

Change-Id: I5d4b6acfcfdf0e3efcf6eb49c5e6cf4521e4baed
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 0aa4c6f147 net/dns/resolver: add debug HTML handler to see what DNS traffic was forwarded
Change-Id: I6b790e92dcc608515ac8b178f2271adc9fd98f78
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 0848b36dd2 net/dns/resolver: add metrics to PTR lookup misses
Updates tailscale/corp#3326

Change-Id: I58077d889a3b58ef0633267c92ffb265686ce152
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 39f22a357d net/dns/resolver: send NXDOMAIN to iOS DNS-SD/Bonjour queries
Don't just ignore them. See if this makes them calm down.

Updates #3363

Change-Id: Id1d66308e26660d26719b2538b577522a1e36b63
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 394c9de02b net/dns/resolver: add nameFromQuery benchmark
To convince me it's not as alloc-y as it looks.

Change-Id: I503a0cc267268a23d2973dfde9833c420be4e868
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick c7052154d5 net/dns/resolver: fix the subject in a func comment
Change-Id: I519268c20dbd2c2da92da565839d3c1c84612dcc
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 486059589b all: gofmt -w -s (simplify) tests
And it updates the build tag style on a couple files.

Change-Id: I84478d822c8de3f84b56fa1176c99d2ea5083237
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick cced414c7d net/dns/resolver: add Windows ExitDNS service support, using net package
Updates #1713
Updates #835

Change-Id: Ia71e96d0632c2d617b401695ad68301b07c1c2ec
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick cab5c46481 net/dns: bound how long we block looking for, restarting systemd-resolved
Fixes #3537

Change-Id: Iba6a3cde75983490d4072b5341f48dbfa2f997c0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 39ffa16853 net/dnscache, net/tsdial: add DNS caching to tsdial UserDial
This is enough to handle the DNS queries as generated by Go's
net package (which our HTTP/SOCKS client uses), and the responses
generated by the ExitDNS DoH server.

This isn't yet suitable for putting on 100.100.100.100 where a number
of different DNS clients would hit it, as this doesn't yet do
EDNS0. It might work, but it's untested and likely incomplete.

Likewise, this doesn't handle anything about truncation, as the
exchanges are entirely in memory between Go or DoH. That would also
need to be handled later, if/when it's hooked up to 100.100.100.100.

Updates #3507

Change-Id: I1736b0ad31eea85ea853b310c52c5e6bf65c6e2a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 21741e111b net/packet: add ICMP6Header, like ICMP4Header
So we can generate IPv6 ping replies.

Change-Id: I79a9a38d8aa242e5dfca4cd15dfaffaea6cb1aee
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick affc4530a2 net/packet: don't make IP6Header.marshalPseudo assume UDP
It will be used for ICMPv6 next, so pass in the proto.

Also, use the ipproto constants rather than hardcoding the mysterious
number.

Change-Id: I57b68bdd2d39fff75f82affe955aff9245de246b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 485bcdc951 net/packet: fix doc copy/paste-o
Change-Id: I0aca490b3ccb0c124192afb362a10b19a15a3e2b
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 9c5c9d0a50 ipn/ipnlocal, net/tsdial: make SOCKS/HTTP dials use ExitDNS
And simplify, unexport some tsdial/netstack stuff in the the process.

Fixes #3475

Change-Id: I186a5a5cbd8958e25c075b4676f7f6e70f3ff76e
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick adc5997592 net/tsdial: give netstack a Dialer, start refactoring name resolution
This starts to refactor tsdial.Dialer's name resolution to have
different stages: in-memory MagicDNS vs system resolution. A future
change will plug in ExitDNS resolution.

This also plumbs a Dialer into netstack and unexports the dnsMap
internals.

And it removes some of the async AddNetworkMapCallback usage and
replaces it with synchronous updates of the Dialer's netmap
from LocalBackend, since the LocalBackend has the Dialer too.

Updates #3475

Change-Id: Idcb7b1169878c74f0522f5151031ccbc49fe4cb4
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 8775c646be net/tsdial: make dialing to peerapi work in netstack mode
With this, I'm able to send a Taildrop file (using "tailscale file cp")
from a Linux machine running --tun=userspace-networking.

Updates #2179

Change-Id: I4e7a4fb0fbda393e4fb483adb06b74054a02cfd0
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick ad3d6e31f0 net/tsdial: move macOS/iOS peerapi sockopt logic from LocalBackend
Change-Id: I812cae027c40c70cdc701427b1a1850cd9bcd60c
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick c7fb26acdb net/tsdial: also plumb TUN name and monitor into tsdial.Dialer
In prep for moving stuff out of LocalBackend.

Change-Id: I9725aa9c3ebc7275f8c40e040b326483c0340127
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick c37af58ea4 net/tsdial: move more weirdo dialing into new tsdial package, plumb
Not done yet, but this move more of the outbound dial special casing
from random packages into tsdial, which aspires to be the one unified
place for all outbound dialing shenanigans.

Then this plumbs it all around, so everybody is ultimately
holding on to the same dialer.

As of this commit, macOS/iOS using an exit node should be able to
reach to the exit node's DoH DNS proxy over peerapi, doing the sockopt
to stay within the Network Extension.

A number of steps remain, including but limited to:

* move a bunch more random dialing stuff

* make netstack-mode tailscaled be able to use exit node's DNS proxy,
  teaching tsdial's resolver to use it when an exit node is in use.

Updates #1713

Change-Id: I1e8ee378f125421c2b816f47bc2c6d913ddcd2f5
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Josh Bleecher Snyder 2075c39fd7 net/portmapper: deflake TestPCPIntegration
Logging in goroutines after the test completed
caused data races and panics. Prevent that.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick d5405c66b7 net/tsdial: start of new package to unify all outbound dialing complexity
For now this just deletes the net/socks5/tssocks implementation (and
the DNSMap stuff from wgengine/netstack) and moves it into net/tsdial.

Then initialize a Dialer early in tailscaled, currently only use for the
outbound and SOCKS5 proxies. It will be plumbed more later. Notably, it
needs to get down into the DNS forwarder for exit node DNS forwading
in netstack mode. But it will also absorb all the peerapi setsockopt
and netns Dial and tlsdial complexity too.

Updates #1713

Change-Id: Ibc6d56ae21a22655b2fa1002d8fc3f2b2ae8b6df
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 3ae6f898cf ipn/ipnlocal, net/dns/resolver: use exit node's DoH proxy when available
Updates #1713

Change-Id: I3695a40ec12d2b4e6dac41cf4559daca6dddd68e
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Aaron Klotz f93cf6fa03 net/dns: fix checking for wrapped error when attempting to read wsl.conf for Windows WSL2
Fixes https://github.com/tailscale/tailscale/issues/3437

Signed-off-by: Aaron Klotz <aaron@tailscale.com>
3 years ago
David Anderson 124363e0ca net/dns: detect and decode UTF-16 from wsl.exe earlier.
Fixes #3170

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Josh Bleecher Snyder e16cb523aa net/nettest: deflake TestPipeTimeout
The block-write and block-read tests are both flaky,
because each assumes it can get a normal read/write
completed within 10ms. This isn’t always true.

We can’t increase the timeouts, because that slows down the test.
However, we don’t need to issue a regular read/write for this test.
The immediately preceding tests already test this code,
using a far more generous timeout.

Remove the extraneous read/write.

This drops the failure rate from 1 per 20,000 to undetectable
on my machine.

While we’re here, fix a typo in a debug print statement.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder a8cc519c70 net/portmapper: improve handling of UPnP parse errors
Without the continue, we might overwrite our current meta
with a zero meta.

Log the error, so that we can check for anything unexpected.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder fddf43f3d1 net/portmapper: fill out PCP/PMP client metrics
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 9787ec6f4a net/portmapper: add UPnP client metrics
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 40f11c50a1 net/portmapper: make PCP/PMP result codes stringers
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 38d90fa330 net/portmapper: add clientmetrics for PCP/PMP responses
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 999814e9e1 net/portmapper: handle pcp ADDRESS_MISMATCH response
These show up a fair amount in our logs.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick bb91cfeae7 net/socks5/tssocks, wgengine: permit SOCKS through subnet routers/exit nodes
Fixes #1970

Change-Id: Ibef45e8796e1d9625716d72539c96d1dbf7b1f76
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
David Anderson a54d13294f net/proxymux: add a listener mux that can run SOCKS and HTTP on a single socket.
Updates #3248

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
Brad Fitzpatrick 135580a5a8 tailcfg, ipn/ipnlocal, net/dns: forward exit node DNS on Unix to system DNS
Updates #1713

Change-Id: I4c073fec0992d9e01a9a4ce97087d5af0efdc68d
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 78b0bd2957 net/dns/resolver: add clientmetrics for DNS
Fixes tailscale/corp#1811

Change-Id: I864d11e0332a177e8c5ff403591bff6fec548f5a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Brad Fitzpatrick 25525b7754 net/dns/resolver, ipn/ipnlocal: wire up peerapi DoH server to DNS forwarder
Updates #1713

Change-Id: Ia4ed9d8c9cef0e70aa6d30f2852eaab80f5f695a
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Josh Bleecher Snyder d10cefdb9b net/dns: require space after nameserver/search parsing resolv.conf
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 9f00510833 net/dns: handle comments in resolv.conf
Currently, comments in resolv.conf cause our parser to fail,
with error messages like:

ParseIP("192.168.0.100 # comment"): unexpected character (at " # comment")

Fix that.

Noticed while looking through logs.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 73beaaf360 net/tstun: rate limit "self disco out packet" logging
When this happens, it is incredibly noisy in the logs.
It accounts for about a third of all remaining
"unexpected" log lines from a recent investigation.

It's not clear that we know how to fix this,
we have a functioning workaround,
and we now have a (cheap and efficient) metric for this
that we can use for measurements.

So reduce the logging to approximately once per minute.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Brad Fitzpatrick 283ae702c1 ipn/ipnlocal: start adding DoH DNS server to peerapi when exit node
Updates #1713

Change-Id: I8d9c488f779e7acc811a9bc18166a2726198a429
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
3 years ago
Josh Bleecher Snyder ad5e04249b wgengine/monitor: ignore adding/removing uninteresting IPs
One of the most common "unexpected" log lines is:

"network state changed, but stringification didn't"

One way that this can occur is if an interesting interface
(non-Tailscale, has interesting IP address)
gains or loses an uninteresting IP address (link local or loopback).

The fact that the interface is interesting is enough for EqualFiltered
to inspect it. The fact that an IP address changed is enough for
EqualFiltered to declare that the interfaces are not equal.

But the State.String method reasonably declines to print any
uninteresting IP addresses. As a result, the network state appears
to have changed, but the stringification did not.

The String method is correct; nothing interesting happened.

This change fixes this by adding an IP address filter to EqualFiltered
in addition to the interface filter. This lets the network monitor
ignore the addition/removal of uninteresting IP addresses.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder ca1b3fe235 net/tshttpproxy: use correct size for Windows BOOL argument
The Windows BOOL type is an int32. We were using a bool,
which is a one byte wide. This could be responsible for the
ERROR_INVALID_PARAMETER errors we were seeing for calls to
WinHttpGetProxyForUrl.

We manually checked all other existing Windows syscalls
for similar mistakes and did not find any.

Updates #879

Co-authored-by: Aaron Klotz <aaron@tailscale.com>
Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
Josh Bleecher Snyder 1a629a4715 net/portmapper: mark fewer PMP probe failures as unexpected
There are lots of lines in the logs of the form:

portmapper: unexpected PMP probe response: {OpCode:128 ResultCode:3
SecondsSinceEpoch:NNN MappingValidSeconds:0 InternalPort:0
ExternalPort:0 PublicAddr:0.0.0.0}

ResultCode 3 here means a network failure, e.g. the NAT box itself has
not obtained a DHCP lease. This is not an indication that something
is wrong in the Tailscale client, so use different wording here
to reflect that. Keep logging, so that we can analyze and debug
the reasons that PMP probes fail.

Signed-off-by: Josh Bleecher Snyder <josh@tailscale.com>
3 years ago
David Anderson 88b8a09d37 net/dns: make constants for the various DBus strings.
Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago
David Anderson 6c82cebe57 health: add a health state for net/dns.OSConfigurator.
Lets the systemd-resolved OSConfigurator report health changes
for out of band config resyncs.

Updates #3327

Signed-off-by: David Anderson <danderson@tailscale.com>
3 years ago