tailscale

Commit Graph

Author	SHA1	Message	Date
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	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
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	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	aaf2df7ab1	net/{dnscache,interfaces}: use netaddr.IP.IsPrivate, delete copied code Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	3 years ago
Brad Fitzpatrick	c17d743886	net/dnscache: update a comment Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	3 years ago
Brad Fitzpatrick	281d503626	net/dnscache: make Dialer try all resolved IPs Tested manually with: $ go test -v ./net/dnscache/ -dial-test=bogusplane.dev.tailscale.com:80 Where bogusplane has three A records, only one of which works. Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	3 years ago
Brad Fitzpatrick	e299300b48	net/dnscache: cache all IPs per hostname Not yet used in the dialer, but plumbed around. Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	3 years ago
Brad Fitzpatrick	9df4185c94	control/controlclient, net/{dnscache,dnsfallback}: add DNS fallback mechanism Updates #1405 Updates #1403 Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	4 years ago
Brad Fitzpatrick	66be052a70	net/dnscache: work on IPv6-only hosts (again) This fixes the regression where we had stopped working on IPv6-only hosts. Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	4 years ago
Brad Fitzpatrick	a2d78b4d3e	net/dnscache, control/controlclient: use DNS cache when dialing control Cache DNS results of earlier login.tailscale.com control dials, and use them for future dials if DNS is slow or broken. Fixes various issues with trickier setups with the domain's DNS server behind a subnet router. Signed-off-by: Brad Fitzpatrick <bradfitz@tailscale.com>	4 years ago
Brad Fitzpatrick	19b0cfe89e	all: prepare for GOOS=ios in Go 1.16 Work with either way for now on iOS (darwin/arm64 vs ios/arm64). In February when Go 1.16 comes out we'll have a universal binary for darwin/arm64 (macOS) and will drop support for Go 1.15 and its darwin/amd64 meaning iOS. (it'll mean macOS). Context: * https://tip.golang.org/doc/go1.16#darwin * https://github.com/golang/go/issues/38485 * https://github.com/golang/go/issues/42100	4 years ago
David Anderson	657f331e8b	net/dnscache: remove unnecessary lint warning.	5 years ago
Elias Naur	ad0795efc2	net/dnscache: don't use the Go resolver on Android The local resolver is not available for apps on Android. Signed-off-by: Elias Naur <mail@eliasnaur.com>	5 years ago
Brad Fitzpatrick	bd0e20f351	net/dnscache: ignore annoying staticcheck check	5 years ago
Brad Fitzpatrick	d44325295e	net/dnscache: initialize the single Resolver more directly	5 years ago
David Crawshaw	cac68fe102	net/dnscache: do not PreferGo on macOS/iOS With this commit my iPhone can now DERP.	5 years ago
Brad Fitzpatrick	8f0fd01efd	net/dnscache: add copyright header to test	5 years ago
David Crawshaw	5a1ce4adae	net/dnscache: parse passed CIDR Signed-off-by: David Crawshaw <crawshaw@tailscale.com>	5 years ago
Brad Fitzpatrick	2cff9016e4	net/dnscache: add overly simplistic DNS cache package for selective use I started to write a full DNS caching resolver and I realized it was overkill and wouldn't work on Windows even in Go 1.14 yet, so I'm doing this tiny one instead for now, just for all our netcheck STUN derp lookups, and connections to DERP servers. (This will be caching a exactly 8 DNS entries, all ours.) Fixes #145 (can be better later, of course)	5 years ago

22 Commits (53998e26a6ce13de0f2a4b8b747206823f217e86)