Use preshared keys and make pingable (#15)

* make wireguard pingable

* accept preshared key for a peer

* forked to inventage

* Revert "forked to inventage"

This reverts commit d7cdee9.

Author: fbuetler

pkg/wgembed/iface.go

@@ -8,11 +8,12 @@ import (
 
 type WireGuardInterface interface {
 	LoadConfig(config *ConfigFile) error
-	AddPeer(publicKey string, addressCIDR []string) error
+	AddPeer(publicKey string, presharedKey string, addressCIDR []string) error
 	ListPeers() ([]wgtypes.Peer, error)
 	RemovePeer(publicKey string) error
 	PublicKey() (string, error)
 	Close() error
+	Ping() error
 }
 
 // Options contains configuration options for the interface

pkg/wgembed/management.go

@@ -12,12 +12,23 @@ import (
 // AddPeer adds a new peer to the interface.
 // The subnet sizes in addressCIDR should be /32 for IPv4 and /128 for IPv6,
 // as the whole subnet will be added to AllowedIPs for this device.
-func (wg *commonInterface) AddPeer(publicKey string, addressCIDR []string) error {
-	key, err := wgtypes.ParseKey(publicKey)
+// The presharedKey is optinal and can be omitted with nil
+func (wg *commonInterface) AddPeer(publicKey string, presharedKey string, addressCIDR []string) error {
+	wgPublicKey, err := wgtypes.ParseKey(publicKey)
 	if err != nil {
 		return errors.Wrapf(err, "bad public key %v", publicKey)
 	}
 
+	var wgPresharedKey *wgtypes.Key
+	if len(presharedKey) != 0 {
+		psk, err := wgtypes.ParseKey(presharedKey)
+		if err != nil {
+			logrus.WithError(err).Warnf("ignoring bad pre-shared key: %v", presharedKey)
+		} else {
+			wgPresharedKey = &psk
+		}
+	}
+
 	parsedAddresses := make([]net.IPNet, 0, len(addressCIDR))
 	for _, addr := range addressCIDR {
 		_, allowedIPs, err := net.ParseCIDR(addr)
@@ -31,7 +42,8 @@ func (wg *commonInterface) AddPeer(publicKey string, addressCIDR []string) error
 		config.ReplacePeers = false
 		config.Peers = []wgtypes.PeerConfig{
 			{
-				PublicKey:         key,
+				PublicKey:         wgPublicKey,
+				PresharedKey:      wgPresharedKey,
 				AllowedIPs:        parsedAddresses,
 				ReplaceAllowedIPs: true,
 			},
@@ -109,6 +121,13 @@ func (wg *commonInterface) Port() (int, error) {
 	return device.ListenPort, nil
 }
 
+func (wg *commonInterface) Ping() error {
+	if _, err := wg.ListPeers(); err != nil {
+		return errors.New("failed to ping wireguard")
+	}
+	return nil
+}
+
 func (wg *commonInterface) configure(cb func(*wgtypes.Config) error) error {
 	// TODO: concurrency
 	// s.lock.Lock()

pkg/wgembed/noop.go

@@ -13,7 +13,7 @@ func (wg *NoOpWireguardInterface) LoadConfig(config *ConfigFile) error {
 	return nil
 }
 
-func (wg *NoOpWireguardInterface) AddPeer(publicKey string, addressCIDR []string) error {
+func (wg *NoOpWireguardInterface) AddPeer(publicKey string, presharedKey string, addressCIDR []string) error {
 	return nil
 }
 
@@ -32,3 +32,7 @@ func (wg *NoOpWireguardInterface) PublicKey() (string, error) {
 func (wg *NoOpWireguardInterface) Close() error {
 	return nil
 }
+
+func (wg *NoOpWireguardInterface) Ping() error {
+	return nil
+}