cmd/stunstamp: implement service to measure DERP STUN RTT (#12241)

stunstamp timestamping includes userspace and SO_TIMESTAMPING kernel
timestamping where available. Measurements are written locally to a
sqlite DB, exposed over an HTTP API, and written to prometheus
via remote-write protocol.

Updates tailscale/corp#20344

Signed-off-by: Jordan Whited <jordan@tailscale.com>

go.mod

@@ -5,6 +5,7 @@ go 1.22.0
 require (
 	filippo.io/mkcert v1.4.4
 	fybrik.io/crdoc v0.6.3
+	github.com/Masterminds/squirrel v1.5.4
 	github.com/akutz/memconn v0.1.0
 	github.com/alexbrainman/sspi v0.0.0-20231016080023-1a75b4708caa
 	github.com/andybalholm/brotli v1.1.0
@@ -34,6 +35,7 @@ require (
 	github.com/go-ole/go-ole v1.3.0
 	github.com/godbus/dbus/v5 v5.1.1-0.20230522191255-76236955d466
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da
+	github.com/golang/snappy v0.0.4
 	github.com/golangci/golangci-lint v1.52.2
 	github.com/google/go-cmp v0.6.0
 	github.com/google/go-containerregistry v0.18.0
@@ -64,6 +66,7 @@ require (
 	github.com/prometheus-community/pro-bing v0.4.0
 	github.com/prometheus/client_golang v1.18.0
 	github.com/prometheus/common v0.46.0
+	github.com/prometheus/prometheus v0.49.2-0.20240125131847-c3b8ef1694ff
 	github.com/safchain/ethtool v0.3.0
 	github.com/skip2/go-qrcode v0.0.0-20200617195104-da1b6568686e
 	github.com/studio-b12/gowebdav v0.9.0
@@ -91,14 +94,14 @@ require (
 	go4.org/netipx v0.0.0-20231129151722-fdeea329fbba
 	golang.org/x/crypto v0.21.0
 	golang.org/x/exp v0.0.0-20240119083558-1b970713d09a
-	golang.org/x/mod v0.14.0
+	golang.org/x/mod v0.16.0
 	golang.org/x/net v0.23.0
 	golang.org/x/oauth2 v0.16.0
 	golang.org/x/sync v0.6.0
-	golang.org/x/sys v0.18.0
+	golang.org/x/sys v0.19.0
 	golang.org/x/term v0.18.0
 	golang.org/x/time v0.5.0
-	golang.org/x/tools v0.17.0
+	golang.org/x/tools v0.19.0
 	golang.zx2c4.com/wintun v0.0.0-20230126152724-0fa3db229ce2
 	golang.zx2c4.com/wireguard/windows v0.5.3
 	gopkg.in/square/go-jose.v2 v2.6.0
@@ -108,6 +111,7 @@ require (
 	k8s.io/apimachinery v0.29.1
 	k8s.io/apiserver v0.29.1
 	k8s.io/client-go v0.29.1
+	modernc.org/sqlite v1.29.10
 	nhooyr.io/websocket v1.8.10
 	sigs.k8s.io/controller-runtime v0.16.2
 	sigs.k8s.io/controller-tools v0.13.0
@@ -121,9 +125,21 @@ require (
 	github.com/cyphar/filepath-securejoin v0.2.4 // indirect
 	github.com/dave/astrid v0.0.0-20170323122508-8c2895878b14 // indirect
 	github.com/dave/brenda v1.1.0 // indirect
+	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/gobuffalo/flect v1.0.2 // indirect
 	github.com/google/gnostic-models v0.6.9-0.20230804172637-c7be7c783f49 // indirect
 	github.com/gorilla/securecookie v1.1.2 // indirect
+	github.com/hashicorp/golang-lru/v2 v2.0.7 // indirect
+	github.com/lann/builder v0.0.0-20180802200727-47ae307949d0 // indirect
+	github.com/lann/ps v0.0.0-20150810152359-62de8c46ede0 // indirect
+	github.com/ncruces/go-strftime v0.1.9 // indirect
+	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
+	modernc.org/gc/v3 v3.0.0-20240107210532-573471604cb6 // indirect
+	modernc.org/libc v1.49.3 // indirect
+	modernc.org/mathutil v1.6.0 // indirect
+	modernc.org/memory v1.8.0 // indirect
+	modernc.org/strutil v1.2.0 // indirect
+	modernc.org/token v1.1.0 // indirect
 )
 
 require (
@@ -179,7 +195,7 @@ require (
 	github.com/containerd/stargz-snapshotter/estargz v0.15.1 // indirect
 	github.com/curioswitch/go-reassign v0.2.0 // indirect
 	github.com/daixiang0/gci v0.10.1 // indirect
-	github.com/davecgh/go-spew v1.1.1 // indirect
+	github.com/davecgh/go-spew v1.1.2-0.20180830191138-d8f796af33cc // indirect
 	github.com/denis-tingaikin/go-header v0.4.3 // indirect
 	github.com/docker/cli v25.0.0+incompatible // indirect
 	github.com/docker/distribution v2.8.3+incompatible // indirect
@@ -276,7 +292,7 @@ require (
 	github.com/matoous/godox v0.0.0-20230222163458-006bad1f9d26 // indirect
 	github.com/mattn/go-runewidth v0.0.14 // indirect
 	github.com/mbilski/exhaustivestruct v1.2.0 // indirect
-	github.com/mdlayher/socket v0.5.0 // indirect
+	github.com/mdlayher/socket v0.5.0
 	github.com/mgechev/revive v1.3.1 // indirect
 	github.com/mitchellh/copystructure v1.2.0 // indirect
 	github.com/mitchellh/go-homedir v1.1.0 // indirect
@@ -299,7 +315,7 @@ require (
 	github.com/pierrec/lz4/v4 v4.1.21 // indirect
 	github.com/pjbgf/sha1cd v0.3.0 // indirect
 	github.com/pkg/diff v0.0.0-20210226163009-20ebb0f2a09e // indirect
-	github.com/pmezard/go-difflib v1.0.0 // indirect
+	github.com/pmezard/go-difflib v1.0.1-0.20181226105442-5d4384ee4fb2 // indirect
 	github.com/polyfloyd/go-errorlint v1.4.1 // indirect
 	github.com/prometheus/client_model v0.5.0 // indirect
 	github.com/prometheus/procfs v0.12.0 // indirect