Add alias when connecting to exit node

olm/exitnode.go

@@ -3,6 +3,7 @@ package olm
 import (
 	"encoding/json"
 	"fmt"
+	"net"
 	"strings"
 
 	"github.com/fosrl/newt/logger"
@@ -12,6 +13,12 @@ import (
 	"github.com/fosrl/olm/websocket"
 )
 
+// exitNodeAliasSiteId is the sentinel siteId used when registering exit node
+// aliases with the DNS proxy. It is not a real site, and the JIT handler
+// treats siteId 0 as "no JIT lookup", which is correct here since the exit
+// node is connected directly rather than on demand.
+const exitNodeAliasSiteId = 0
+
 // connectExitNode configures a WireGuard peer connection to an exit node, on the
 // same interface and WireGuard device already used for site peers. The exit node
 // lives in a different address space than the site tunnel, so a secondary address
@@ -87,6 +94,18 @@ persistent_keepalive_interval=%d`, util.FixKey(cfg.PublicKey), allowedIP, resolv
 	cfgCopy := cfg
 	o.exitNode = &cfgCopy
 
+	if o.dnsProxy != nil {
+		serverIP := net.ParseIP(cfg.ServerIP)
+		if serverIP != nil {
+			for _, alias := range cfg.Aliases {
+				logger.Debug("Adding alias %s to the edit node", alias)
+				if err := o.dnsProxy.AddDNSRecord(alias, serverIP, exitNodeAliasSiteId); err != nil {
+					logger.Warn("Failed to add DNS record for exit node alias %s: %v", alias, err)
+				}
+			}
+		}
+	}
+
 	logger.Info("Connected to exit node at %s", resolvedEndpoint)
 	return nil
 }
@@ -108,6 +127,15 @@ func (o *Olm) removeExitNodePeerLocked() error {
 	cfg := o.exitNode
 	o.exitNode = nil
 
+	if o.dnsProxy != nil {
+		serverIP := net.ParseIP(cfg.ServerIP)
+		if serverIP != nil {
+			for _, alias := range cfg.Aliases {
+				o.dnsProxy.RemoveDNSRecordForSite(alias, serverIP, exitNodeAliasSiteId)
+			}
+		}
+	}
+
 	if o.dev != nil {
 		if err := peers.RemovePeer(o.dev, 0, cfg.PublicKey); err != nil {
 			logger.Warn("Failed to remove exit node peer: %v", err)

olm/types.go

@@ -21,12 +21,13 @@ type WgData struct {
 // also be sent later via "olm/wg/exitnode/connect" / "olm/wg/exitnode/disconnect"
 // so the server can direct a client to connect/disconnect after registration.
 type ExitNodeConfig struct {
-	Connect   bool   `json:"connect"`
-	Endpoint  string `json:"endpoint"`
-	RelayPort uint16 `json:"relayPort"`
-	PublicKey string `json:"publicKey"`
-	ServerIP  string `json:"serverIP"`
-	TunnelIP  string `json:"tunnelIP"`
+	Connect   bool     `json:"connect"`
+	Endpoint  string   `json:"endpoint"`
+	RelayPort uint16   `json:"relayPort"`
+	PublicKey string   `json:"publicKey"`
+	ServerIP  string   `json:"serverIP"`
+	TunnelIP  string   `json:"tunnelIP"`
+	Aliases   []string `json:"aliases,omitempty"`
 }
 
 type SyncData struct {