Merge pull request #98 from kradalby/initial-dns-server-exit-node

README.md

@@ -25,8 +25,9 @@ Headscale implements this coordination server.
 - [X] JSON-formatted output
 - [X] ACLs
 - [X] Support for alternative IP ranges in the tailnets (default Tailscale's 100.64.0.0/10)
+- [X] DNS (passing DNS servers to nodes)
 - [ ] Share nodes between ~~users~~ namespaces 
-- [ ] DNS
+- [ ] MagicDNS / Smart DNS
 
 
 ## Roadmap 🤷

api.go

@@ -14,7 +14,6 @@ import (
 	"github.com/gin-gonic/gin"
 	"github.com/klauspost/compress/zstd"
 	"gorm.io/gorm"
-	"inet.af/netaddr"
 	"tailscale.com/tailcfg"
 	"tailscale.com/types/wgkey"
 )
@@ -245,10 +244,15 @@ func (h *Headscale) getMapResponse(mKey wgkey.Key, req tailcfg.MapRequest, m Mac
 	}
 
 	resp := tailcfg.MapResponse{
-		KeepAlive:    false,
+		KeepAlive: false,
-		Node:         node,
+		Node:      node,
-		Peers:        *peers,
+		Peers:     *peers,
-		DNS:          []netaddr.IP{},
+		//TODO(kradalby): As per tailscale docs, if DNSConfig is nil,
+		// it means its not updated, maybe we can have some logic
+		// to check and only pass updates when its updates.
+		// This is probably more relevant if we try to implement
+		// "MagicDNS"
+		DNSConfig:    h.cfg.DNSConfig,
 		SearchPaths:  []string{},
 		Domain:       "headscale.net",
 		PacketFilter: *h.aclRules,

app.go

@@ -43,6 +43,8 @@ type Config struct {
 
 	TLSCertPath string
 	TLSKeyPath  string
+
+	DNSConfig *tailcfg.DNSConfig
 }
 
 // Headscale represents the base app of the service

cmd/headscale/cli/utils.go

@@ -41,6 +41,8 @@ func LoadConfig(path string) error {
 
 	viper.SetDefault("log_level", "info")
 
+	viper.SetDefault("dns_config", nil)
+
 	err := viper.ReadInConfig()
 	if err != nil {
 		return fmt.Errorf("Fatal error reading config file: %s \n", err)
@@ -70,6 +72,45 @@ func LoadConfig(path string) error {
 	} else {
 		return nil
 	}
+
+}
+
+func GetDNSConfig() *tailcfg.DNSConfig {
+	if viper.IsSet("dns_config") {
+		dnsConfig := &tailcfg.DNSConfig{}
+
+		if viper.IsSet("dns_config.nameservers") {
+			nameserversStr := viper.GetStringSlice("dns_config.nameservers")
+
+			nameservers := make([]netaddr.IP, len(nameserversStr))
+			resolvers := make([]tailcfg.DNSResolver, len(nameserversStr))
+
+			for index, nameserverStr := range nameserversStr {
+				nameserver, err := netaddr.ParseIP(nameserverStr)
+				if err != nil {
+					log.Error().
+						Str("func", "getDNSConfig").
+						Err(err).
+						Msgf("Could not parse nameserver IP: %s", nameserverStr)
+				}
+
+				nameservers[index] = nameserver
+				resolvers[index] = tailcfg.DNSResolver{
+					Addr: nameserver.String(),
+				}
+			}
+
+			dnsConfig.Nameservers = nameservers
+			dnsConfig.Resolvers = resolvers
+		}
+		if viper.IsSet("dns_config.domains") {
+			dnsConfig.Domains = viper.GetStringSlice("dns_config.domains")
+		}
+
+		return dnsConfig
+	}
+
+	return nil
 }
 
 func absPath(path string) string {
@@ -126,6 +167,8 @@ func getHeadscaleApp() (*headscale.Headscale, error) {
 
 		TLSCertPath: absPath(viper.GetString("tls_cert_path")),
 		TLSKeyPath:  absPath(viper.GetString("tls_key_path")),
+
+		DNSConfig: GetDNSConfig(),
 	}
 
 	h, err := headscale.NewHeadscale(cfg)

cmd/headscale/headscale_test.go

@@ -58,7 +58,7 @@ func (*Suite) TestPostgresConfigLoading(c *check.C) {
 	c.Assert(viper.GetString("db_port"), check.Equals, "5432")
 	c.Assert(viper.GetString("tls_letsencrypt_hostname"), check.Equals, "")
 	c.Assert(viper.GetString("tls_letsencrypt_listen"), check.Equals, ":http")
-	c.Assert(viper.GetString("tls_letsencrypt_challenge_type"), check.Equals, "HTTP-01")
+	c.Assert(viper.GetStringSlice("dns_config.nameservers")[0], check.Equals, "1.1.1.1")
 }
 
 func (*Suite) TestSqliteConfigLoading(c *check.C) {
@@ -92,6 +92,37 @@ func (*Suite) TestSqliteConfigLoading(c *check.C) {
 	c.Assert(viper.GetString("tls_letsencrypt_hostname"), check.Equals, "")
 	c.Assert(viper.GetString("tls_letsencrypt_listen"), check.Equals, ":http")
 	c.Assert(viper.GetString("tls_letsencrypt_challenge_type"), check.Equals, "HTTP-01")
+	c.Assert(viper.GetStringSlice("dns_config.nameservers")[0], check.Equals, "1.1.1.1")
+}
+
+func (*Suite) TestDNSConfigLoading(c *check.C) {
+	tmpDir, err := ioutil.TempDir("", "headscale")
+	if err != nil {
+		c.Fatal(err)
+	}
+	defer os.RemoveAll(tmpDir)
+
+	path, err := os.Getwd()
+	if err != nil {
+		c.Fatal(err)
+	}
+
+	// Symlink the example config file
+	err = os.Symlink(filepath.Clean(path+"/../../config.json.sqlite.example"), filepath.Join(tmpDir, "config.json"))
+	if err != nil {
+		c.Fatal(err)
+	}
+
+	// Load example config, it should load without validation errors
+	err = cli.LoadConfig(tmpDir)
+	c.Assert(err, check.IsNil)
+
+	dnsConfig := cli.GetDNSConfig()
+	fmt.Println(dnsConfig)
+
+	c.Assert(dnsConfig.Nameservers[0].String(), check.Equals, "1.1.1.1")
+
+	c.Assert(dnsConfig.Resolvers[0].Addr, check.Equals, "1.1.1.1")
 }
 
 func writeConfig(c *check.C, tmpDir string, configYaml []byte) {

config.json.postgres.example

@@ -16,5 +16,10 @@
     "tls_letsencrypt_challenge_type": "HTTP-01",
     "tls_cert_path": "",
     "tls_key_path": "",
-    "acl_policy_path": ""
+    "acl_policy_path": "",
+    "dns_config": {
+        "nameservers": [
+            "1.1.1.1"
+        ]
+    }
 }

config.json.sqlite.example

@@ -12,5 +12,10 @@
     "tls_letsencrypt_challenge_type": "HTTP-01",
     "tls_cert_path": "",
     "tls_key_path": "",
-    "acl_policy_path": ""
+    "acl_policy_path": "",
+    "dns_config": {
+        "nameservers": [
+            "1.1.1.1"
+        ]
+    }
 }