register tailscale/udp network for HTTP3

Updates #33

Signed-off-by: Will Norris <will@tailscale.com>

go.mod

@@ -6,7 +6,7 @@ require (
 	github.com/caddyserver/caddy/v2 v2.7.3
 	github.com/google/go-cmp v0.6.0
 	go.uber.org/zap v1.26.0
-	tailscale.com v1.67.0-pre.0.20240510224123-fc1ae97e1037
+	tailscale.com v1.67.0-pre.0.20240602211424-42cfbf427c67
 )
 
 require (
@@ -67,7 +67,7 @@ require (
 	github.com/google/cel-go v0.15.1 // indirect
 	github.com/google/nftables v0.2.1-0.20240414091927-5e242ec57806 // indirect
 	github.com/google/pprof v0.0.0-20230808223545-4887780b67fb // indirect
-	github.com/google/uuid v1.5.0 // indirect
+	github.com/google/uuid v1.6.0 // indirect
 	github.com/gorilla/csrf v1.7.2 // indirect
 	github.com/gorilla/securecookie v1.1.2 // indirect
 	github.com/hdevalence/ed25519consensus v0.2.0 // indirect
@@ -109,6 +109,7 @@ require (
 	github.com/onsi/ginkgo/v2 v2.11.0 // indirect
 	github.com/pierrec/lz4/v4 v4.1.21 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
+	github.com/prometheus-community/pro-bing v0.4.0 // indirect
 	github.com/prometheus/client_golang v1.18.0 // indirect
 	github.com/prometheus/client_model v0.5.0 // indirect
 	github.com/prometheus/common v0.46.0 // indirect

go.sum

@@ -276,8 +276,8 @@ github.com/google/s2a-go v0.1.4 h1:1kZ/sQM3srePvKs3tXAvQzo66XfcReoqFpIpIccE7Oc=
 github.com/google/s2a-go v0.1.4/go.mod h1:Ej+mSEMGRnqRzjc7VtF+jdBwYG5fuJfiZ8ELkjEwM0A=
 github.com/google/uuid v1.0.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/google/uuid v1.1.1/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
-github.com/google/uuid v1.5.0 h1:1p67kYwdtXjb0gL0BPiP1Av9wiZPo5A8z2cWkTZ+eyU=
-github.com/google/uuid v1.5.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
+github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
+github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/googleapis/enterprise-certificate-proxy v0.2.5 h1:UR4rDjcgpgEnqpIEvkiqTYKBCKLNmlge2eVjoZfySzM=
 github.com/googleapis/enterprise-certificate-proxy v0.2.5/go.mod h1:RxW0N9901Cko1VOCW3SXCpWP+mlIEkk2tP7jnHy9a3w=
 github.com/googleapis/gax-go/v2 v2.12.0 h1:A+gCJKdRfqXkr+BIRGtZLibNXf0m1f9E4HG56etFpas=
@@ -545,6 +545,8 @@ github.com/pkg/sftp v1.13.6/go.mod h1:tz1ryNURKu77RL+GuCzmoJYxQczL3wLNNpPWagdg4Q
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/posener/complete v1.1.1/go.mod h1:em0nMJCgc9GFtwrmVmEMR/ZL6WyhyjMBndrE9hABlRI=
+github.com/prometheus-community/pro-bing v0.4.0 h1:YMbv+i08gQz97OZZBwLyvmmQEEzyfyrrjEaAchdy3R4=
+github.com/prometheus-community/pro-bing v0.4.0/go.mod h1:b7wRYZtCcPmt4Sz319BykUU241rWLe1VFXyiyWK/dH4=
 github.com/prometheus/client_golang v0.9.1/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXPKyh/dDVn+NZz0KFw=
 github.com/prometheus/client_golang v0.9.3-0.20190127221311-3c4408c8b829/go.mod h1:p2iRAGwDERtqlqzRXnrOVns+ignqQo//hLXqYxZYVNs=
 github.com/prometheus/client_golang v1.0.0/go.mod h1:db9x61etRT2tGnBNRi70OPL5FsnadC4Ky3P0J6CfImo=
@@ -1007,5 +1009,5 @@ sigs.k8s.io/yaml v1.1.0/go.mod h1:UJmg0vDUVViEyp3mgSv9WPwZCDxu4rQW1olrI1uml+o=
 software.sslmate.com/src/go-pkcs12 v0.4.0 h1:H2g08FrTvSFKUj+D309j1DPfk5APnIdAQAB8aEykJ5k=
 software.sslmate.com/src/go-pkcs12 v0.4.0/go.mod h1:Qiz0EyvDRJjjxGyUQa2cCNZn/wMyzrRJ/qcDXOQazLI=
 sourcegraph.com/sourcegraph/appdash v0.0.0-20190731080439-ebfcffb1b5c0/go.mod h1:hI742Nqp5OhwiqlzhgfbWU4mW4yO10fP+LoT9WOswdU=
-tailscale.com v1.67.0-pre.0.20240510224123-fc1ae97e1037 h1:ZrUO++qvsCa1jRyg5QI2mrEY3/LgEg4UETvYwgFAIYw=
-tailscale.com v1.67.0-pre.0.20240510224123-fc1ae97e1037/go.mod h1:99BIV4U3UPw36Sva04xK2ZsEpVRUkY9jCdEDSAhaNGM=
+tailscale.com v1.67.0-pre.0.20240602211424-42cfbf427c67 h1:wYdsZWqsAXj4rXmxhxOUbKlNWX4cfbmCxGVCJgfx34c=
+tailscale.com v1.67.0-pre.0.20240602211424-42cfbf427c67/go.mod h1:fI1Vx71PB5JSJv93FKNSmdD0X5QnBuGllLk67AmeNRo=

module.go

@@ -9,21 +9,26 @@ import (
 	"crypto/tls"
 	"fmt"
 	"net"
+	"net/netip"
 	"os"
 	"path/filepath"
+	"strconv"
 	"strings"
 
 	"github.com/caddyserver/caddy/v2"
+	"github.com/caddyserver/caddy/v2/modules/caddyhttp"
 	"go.uber.org/zap"
 	"tailscale.com/tsnet"
 )
 
 func init() {
-	caddy.RegisterNetwork("tailscale", getPlainListener)
+	caddy.RegisterNetwork("tailscale", getTCPListener)
 	caddy.RegisterNetwork("tailscale+tls", getTLSListener)
+	caddy.RegisterNetwork("tailscale/udp", getUDPListener)
+	caddyhttp.RegisterNetworkHTTP3("tailscale", "tailscale/udp")
 }
 
-func getPlainListener(c context.Context, _ string, addr string, _ net.ListenConfig) (any, error) {
+func getTCPListener(c context.Context, _ string, addr string, _ net.ListenConfig) (any, error) {
 	ctx, ok := c.(caddy.Context)
 	if !ok {
 		return nil, fmt.Errorf("context is not a caddy.Context: %T", c)
@@ -78,6 +83,43 @@ func getTLSListener(c context.Context, _ string, addr string, _ net.ListenConfig
 	return ln, nil
 }
 
+func getUDPListener(c context.Context, _ string, addr string, _ net.ListenConfig) (any, error) {
+	ctx, ok := c.(caddy.Context)
+	if !ok {
+		return nil, fmt.Errorf("context is not a caddy.Context: %T", c)
+	}
+
+	network, host, port, err := caddy.SplitNetworkAddress(addr)
+	if err != nil {
+		return nil, err
+	}
+
+	s, err := getNode(ctx, host)
+	if err != nil {
+		return nil, err
+	}
+
+	st, err := s.Up(context.Background())
+	if err != nil {
+		return nil, err
+	}
+
+	if network == "" {
+		network = "udp4"
+
+	}
+	var ap netip.AddrPort
+	for _, ip := range st.TailscaleIPs {
+		// TODO(will): watch for Tailscale IP changes and update listener
+		if (network == "udp4" && ip.Is4()) || (network == "udp6" && ip.Is6()) {
+			p, _ := strconv.Atoi(port)
+			ap = netip.AddrPortFrom(ip, uint16(p))
+			break
+		}
+	}
+	return s.Server.ListenPacket(network, ap.String())
+}
+
 // nodes are the Tailscale nodes that have been configured and started.
 // Node configuration comes from the global Tailscale Caddy app.
 // When nodes are no longer in used (e.g. all listeners have been closed), they are shutdown.