feat: tailscale serve support

config-example.yaml

@@ -242,6 +242,15 @@ policy:
   # HuJSON file containing ACL policies.
   path: ""
 
+
+certificates:
+  enabled: false
+  # Path to an executable that will be called when dns01 challenge is raised by tailscale client.
+  # Command will be called with 3 arguments:  <domain>,<type>,<value>
+  #     Eg: /path/to/set-dns-command "_acme-challenge.node1.example.com" "TXT" "jYhsfThsdf_Lo3shgdBRY7hNxe"
+  set_dns_command: ""
+
+
 ## DNS
 #
 # headscale supports Tailscale's DNS configuration and MagicDNS.

hscontrol/mapper/mapper.go

@@ -124,6 +124,13 @@ func generateDNSConfig(
 
 	addNextDNSMetadata(dnsConfig.Resolvers, node)
 
+	hostname, err := node.GetFQDN(cfg.BaseDomain)
+	if err != nil {
+		log.Warn().Msgf("failed to get FQDN of node %s for certDomains: %s", node.ID, err)
+	} else {
+		dnsConfig.CertDomains = append(dnsConfig.CertDomains, hostname)
+	}
+
 	return dnsConfig
 }
 

hscontrol/mapper/tail.go

@@ -120,6 +120,10 @@ func tailNode(
 		tailcfg.CapabilitySSH:         []tailcfg.RawMessage{},
 	}
 
+	if cfg.CertificatesFeatureConfig.Enabled {
+		tNode.CapMap[tailcfg.CapabilityHTTPS] = []tailcfg.RawMessage{}
+	}
+
 	if cfg.RandomizeClientPort {
 		tNode.CapMap[tailcfg.NodeAttrRandomizeClientPort] = []tailcfg.RawMessage{}
 	}

hscontrol/noise.go

@@ -5,6 +5,8 @@ import (
 	"encoding/json"
 	"io"
 	"net/http"
+	"os"
+	"os/exec"
 
 	"github.com/gorilla/mux"
 	"github.com/juanfont/headscale/hscontrol/types"
@@ -99,6 +101,7 @@ func (h *Headscale) NoiseUpgradeHandler(
 	router.HandleFunc("/machine/register", noiseServer.NoiseRegistrationHandler).
 		Methods(http.MethodPost)
 	router.HandleFunc("/machine/map", noiseServer.NoisePollNetMapHandler)
+	router.HandleFunc("/machine/set-dns", noiseServer.SetDNSHandler).Methods(http.MethodPost)
 
 	noiseServer.httpBaseConfig = &http.Server{
 		Handler:           router,
@@ -232,3 +235,70 @@ func (ns *noiseServer) NoisePollNetMapHandler(
 		sess.serveLongPoll()
 	}
 }
+
+func (ns *noiseServer) SetDNSHandler(
+	writer http.ResponseWriter,
+	req *http.Request,
+) {
+	body, _ := io.ReadAll(req.Body)
+
+	setDnsRequest := tailcfg.SetDNSRequest{}
+	if err := json.Unmarshal(body, &setDnsRequest); err != nil {
+		log.Error().
+			Caller().
+			Err(err).
+			Msg("Cannot parse MapRequest")
+		http.Error(writer, "Internal error", http.StatusInternalServerError)
+
+		return
+	}
+
+	log.Info().
+		Caller().
+		Str("handler", "NoisePollNetMap").
+		Any("headers", req.Header).
+		Str("NodeKey", setDnsRequest.NodeKey.ShortString()).
+		Str("Name", setDnsRequest.Name).
+		Str("Type", setDnsRequest.Type).
+		Str("Value", setDnsRequest.Value).
+		Msg("SetDNSHandler called")
+
+	if !ns.headscale.cfg.CertificatesFeatureConfig.Enabled {
+		http.Error(writer, "certificates feature is not enabled in headscale", http.StatusForbidden)
+		return
+	}
+	cmd := exec.Command(ns.headscale.cfg.CertificatesFeatureConfig.SetDNSCommand, setDnsRequest.Name, setDnsRequest.Type, setDnsRequest.Value)
+	cmd.Stdout = os.Stderr
+	cmd.Stderr = os.Stderr
+	err := cmd.Run()
+
+	if err != nil {
+		log.Error().AnErr("error", err).
+			Strs("args", cmd.Args).
+			Str("NodeKey", setDnsRequest.NodeKey.ShortString()).
+			Str("DnsName", setDnsRequest.Name).
+			Msg("Error running set_dns_command")
+		http.Error(writer, "Failed to execute SetDNSCommand", http.StatusInternalServerError)
+		return
+	}
+
+	resp := tailcfg.SetDNSResponse{}
+	respBody, err := json.Marshal(resp)
+	if err != nil {
+		log.Error().
+			Caller().
+			Msg("Cannot encode message")
+		http.Error(writer, "Internal server error", http.StatusInternalServerError)
+		return
+	}
+
+	writer.Header().Set("Content-Type", "application/json; charset=utf-8")
+	_, err = writer.Write(respBody)
+	if err != nil {
+		log.Error().
+			Caller().
+			Err(err).
+			Msg("Failed to write response")
+	}
+
+}

hscontrol/types/config.go

@@ -81,6 +81,8 @@ type Config struct {
 	// it can be used directly when sending Netmaps to clients.
 	TailcfgDNSConfig *tailcfg.DNSConfig
 
+	CertificatesFeatureConfig CertificatesFeatureConfig
+
 	UnixSocket           string
 	UnixSocketPermission fs.FileMode
 
@@ -162,6 +164,11 @@ type LetsEncryptConfig struct {
 	ChallengeType string
 }
 
+type CertificatesFeatureConfig struct {
+	Enabled       bool
+	SetDNSCommand string
+}
+
 type OIDCConfig struct {
 	OnlyStartIfOIDCIsAvailable bool
 	Issuer                     string
@@ -257,6 +264,9 @@ func LoadConfig(path string, isFile bool) error {
 	viper.SetDefault("tls_letsencrypt_cache_dir", "/var/www/.cache")
 	viper.SetDefault("tls_letsencrypt_challenge_type", HTTP01ChallengeType)
 
+	viper.SetDefault("certificates.enabled", false)
+	viper.SetDefault("certificates.set_dns_command", "")
+
 	viper.SetDefault("log.level", "info")
 	viper.SetDefault("log.format", TextLogFormat)
 
@@ -383,6 +393,10 @@ func validateServerConfig() error {
 		errorText += "Fatal config error: the only supported values for tls_letsencrypt_challenge_type are HTTP-01 and TLS-ALPN-01\n"
 	}
 
+	if (viper.GetBool("certificates.enabled") == true) && viper.GetString("certificates.set_dns_command") == "" {
+		errorText += "Fatal config error: certificates.enabled is set to true, but certificates.set_dns_command is not set\n"
+	}
+
 	if !strings.HasPrefix(viper.GetString("server_url"), "http://") &&
 		!strings.HasPrefix(viper.GetString("server_url"), "https://") {
 		errorText += "Fatal config error: server_url must start with https:// or http://\n"
@@ -893,6 +907,11 @@ func LoadServerConfig() (*Config, error) {
 		ACMEEmail: viper.GetString("acme_email"),
 		ACMEURL:   viper.GetString("acme_url"),
 
+		CertificatesFeatureConfig: CertificatesFeatureConfig{
+			Enabled:       viper.GetBool("certificates.enabled"),
+			SetDNSCommand: os.ExpandEnv(viper.GetString("certificates.set_dns_command")),
+		},
+
 		UnixSocket:           viper.GetString("unix_socket"),
 		UnixSocketPermission: util.GetFileMode("unix_socket_permission"),