Saving endpoint DNS to config

src/cmd/serve.go

@@ -5,6 +5,7 @@ import (
 	"fmt"
 	"io"
 	"log"
+	"net"
 	"net/netip"
 	"os"
 	"slices"
@@ -353,7 +354,15 @@ func (c serveCmdConfig) Run() {
 		Peers: []peer.PeerConfigArgs{
 			{
 				PublicKey: viper.GetString("Relay.Peer.publickey"),
-				Endpoint:  viper.GetString("Relay.Peer.endpoint"),
+				Endpoint: func() string {
+					if len(viper.GetString("Relay.Peer.endpoint")) > 0 {
+						endpoint, err := net.ResolveUDPAddr("udp", (viper.GetString("Relay.Peer.endpoint")))
+						check("failed to resolve endpoint DNS name for '" + viper.GetString("Relay.Peer.endpoint") + "'", err)
+						return endpoint.String()
+					} else {
+						return ""
+					}
+				}(),
 				PersistentKeepaliveInterval: func() int {
 					if len(viper.GetString("Relay.Peer.endpoint")) > 0 {
 						return viper.GetInt("Relay.Peer.keepalive")

src/peer/config.go

@@ -378,14 +378,15 @@ func (c *Config) GetPeerPublicKey(i int) string {
 
 func (c *Config) GetPeerEndpoint(i int) string {
 	if len(c.peers) > i {
+		endpointDNS := c.peers[i].endpointDNS
+		if endpointDNS != "" {
+			return endpointDNS
+		}
 		endpoint := c.peers[i].config.Endpoint
 		if endpoint != nil {
 			return endpoint.String()
 		}
-
-		return ""
 	}
-
 	return ""
 }
 

src/peer/peer_config.go

@@ -15,13 +15,15 @@ import (
 type PeerConfig struct {
 	config     wgtypes.PeerConfig
 	privateKey *wgtypes.Key
+	endpointDNS string
 	nickname   string
 }
 
 type peerConfigJSON struct {
 	Config     wgtypes.PeerConfig
 	PrivateKey *wgtypes.Key
 	Nickname   string
+	EndpointDNS string
 }
 
 type PeerConfigArgs struct {
@@ -87,7 +89,7 @@ func GetPeerConfig(args PeerConfigArgs) (PeerConfig, error) {
 			return PeerConfig{}, err
 		}
 	}
-	
+
 	if args.Nickname != "" {
 		err = c.SetNickname(args.Nickname)
 		if err != nil {
@@ -109,7 +111,7 @@ func NewPeerConfig() (PeerConfig, error) {
 			PublicKey: privateKey.PublicKey(),
 		},
 		privateKey: &privateKey,
-		nickname: "",
+		nickname:   "",
 	}, nil
 }
 
@@ -118,6 +120,7 @@ func (p *PeerConfig) MarshalJSON() ([]byte, error) {
 		p.config,
 		p.privateKey,
 		p.nickname,
+		p.endpointDNS,
 	})
 }
 
@@ -132,6 +135,7 @@ func (p *PeerConfig) UnmarshalJSON(b []byte) error {
 	p.config = tmp.Config
 	p.privateKey = tmp.PrivateKey
 	p.nickname = tmp.Nickname
+	p.endpointDNS = tmp.EndpointDNS
 
 	return nil
 }
@@ -170,12 +174,20 @@ func (p *PeerConfig) SetPresharedKey(presharedKey string) error {
 }
 
 func (p *PeerConfig) SetEndpoint(addr string) error {
-	endpoint, err := net.ResolveUDPAddr("udp", addr)
+	host, _, err := net.SplitHostPort(addr)
 	if err != nil {
 		return err
 	}
-
-	p.config.Endpoint = endpoint
+	ip := net.ParseIP(host)
+	if ip != nil {
+		endpoint, err := net.ResolveUDPAddr("udp", addr)
+		if err != nil {
+			return err
+		}
+		p.config.Endpoint = endpoint
+	} else {
+		p.endpointDNS = addr
+	}
 	return nil
 }
 
@@ -258,13 +270,13 @@ func (p *PeerConfig) SetNickname(nickname string) error {
 func (p *PeerConfig) AsFile() string {
 	var s strings.Builder
 	s.WriteString("[Peer]\n")
-	
+
 	if p.nickname != "" {
 		s.WriteString(fmt.Sprintf("%s Nickname = %s\n", CUSTOM_PREFIX, p.nickname))
 	}
-	
+
 	s.WriteString(fmt.Sprintf("PublicKey = %s\n", p.config.PublicKey.String()))
-	
+
 	ips := []string{}
 	for _, a := range p.config.AllowedIPs {
 		ips = append(ips, a.String())
@@ -275,6 +287,9 @@ func (p *PeerConfig) AsFile() string {
 	if p.config.Endpoint != nil {
 		s.WriteString(fmt.Sprintf("Endpoint = %s\n", p.config.Endpoint.String()))
 	}
+	if p.endpointDNS != "" {
+		s.WriteString(fmt.Sprintf("Endpoint = %s\n", p.endpointDNS))
+	}
 	if p.config.PersistentKeepaliveInterval != nil {
 		s.WriteString(fmt.Sprintf("PersistentKeepalive = %d\n", *p.config.PersistentKeepaliveInterval/time.Second))
 	}
@@ -289,6 +304,9 @@ func (p *PeerConfig) AsIPC() string {
 	if p.config.Endpoint != nil {
 		s.WriteString(fmt.Sprintf("endpoint=%s\n", p.config.Endpoint.String()))
 	}
+	if p.endpointDNS != "" {
+		s.WriteString(fmt.Sprintf("endpoint=%s\n", p.endpointDNS))
+	}
 	for _, a := range p.config.AllowedIPs {
 		s.WriteString(fmt.Sprintf("allowed_ip=%s\n", a.String()))
 	}