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>
To convince me it's not as alloc-y as it looks.
Change-Id: I503a0cc267268a23d2973dfde9833c420be4e868
Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>
When a DNS server claims to be unable or unwilling to handle a request,
instead of passing that refusal along to the client, just treat it as
any other error trying to connect to the DNS server. This prevents DNS
requests from failing based on if a server can respond with a transient
error before another server is able to give an actual response. DNS
requests only failing *sometimes* is really hard to find the cause of
(#1033).
Signed-off-by: Smitty <me@smitop.com>
We currently plumb full URLs for DNS resolvers from the control server
down to the client. But when we pass the values into the net/dns
package, we throw away any URL that isn't a bare IP. This commit
continues the plumbing, and gets the URL all the way to the built in
forwarder. (It stops before plumbing URLs into the OS configurations
that can handle them.)
For #2596
Signed-off-by: David Crawshaw <crawshaw@tailscale.com>
