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>
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>
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>
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>
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>
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>
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>
* 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>
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>
Avoid some work when D-Bus isn't running.
Change-Id: I6f89bb75fdb24c13f61be9b400610772756db1ef
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
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>
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>
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>
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>
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>
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>
Fixes#3660
RELNOTE=MagicDNS now works over IPv6 when CGNAT IPv4 is disabled.
Change-Id: I001e983df5feeb65289abe5012dedd177b841b45
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
And delete the unused code in net/dns/resolver/neterr_*.go.
Change-Id: Ibe62c486bacce2733eb9968c96a98cbbdb2758bd
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
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>
To convince me it's not as alloc-y as it looks.
Change-Id: I503a0cc267268a23d2973dfde9833c420be4e868
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
And it updates the build tag style on a couple files.
Change-Id: I84478d822c8de3f84b56fa1176c99d2ea5083237
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
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>
