chore!(amneziawg): refactor to be separate from wireguard

- amneziawg is now a VPN protocol and no longer a Wireguard implementation
- Use it with VPN_TYPE=amneziawg
- document AMNEZIAWG_* options in Dockerfile
- document amneziawg support in readme
- separate amneziawg settings and code from wireguard
- re-use code from wireguard whenever possible

internal/vpn/amneziawg.go

@@ -0,0 +1,67 @@
+package vpn
+
+import (
+	"context"
+	"fmt"
+
+	"github.com/qdm12/gluetun/internal/amneziawg"
+	"github.com/qdm12/gluetun/internal/configuration/settings"
+	"github.com/qdm12/gluetun/internal/models"
+	"github.com/qdm12/gluetun/internal/provider"
+	"github.com/qdm12/gluetun/internal/wireguard"
+	"github.com/qdm12/gosettings"
+)
+
+// setupAmneziaWg sets AmneziaWG up using the configurators and settings given.
+func setupAmneziaWg(ctx context.Context, netlinker NetLinker,
+	fw Firewall, providerConf provider.Provider,
+	settings settings.VPN, ipv6Supported bool, logger wireguard.Logger) (
+	amneziawger *amneziawg.Amneziawg, connection models.Connection, err error,
+) {
+	connection, err = providerConf.GetConnection(settings.Provider.ServerSelection, ipv6Supported)
+	if err != nil {
+		return nil, models.Connection{}, fmt.Errorf("finding a VPN server: %w", err)
+	}
+
+	amneziaWGSettings := buildAmneziaWgSettings(connection, settings.AmneziaWg, ipv6Supported)
+
+	logger.Debug("Amneziawg server public key: " + amneziaWGSettings.Wireguard.PublicKey)
+	logger.Debug("Amneziawg client private key: " + gosettings.ObfuscateKey(amneziaWGSettings.Wireguard.PrivateKey))
+	logger.Debug("Amneziawg pre-shared key: " + gosettings.ObfuscateKey(amneziaWGSettings.Wireguard.PreSharedKey))
+
+	amneziawger, err = amneziawg.New(amneziaWGSettings, netlinker, logger)
+	if err != nil {
+		return nil, models.Connection{}, fmt.Errorf("creating amneziawg: %w", err)
+	}
+
+	err = fw.SetVPNConnection(ctx, connection, settings.Wireguard.Interface)
+	if err != nil {
+		return nil, models.Connection{}, fmt.Errorf("setting firewall: %w", err)
+	}
+
+	return amneziawger, connection, nil
+}
+
+func buildAmneziaWgSettings(connection models.Connection,
+	userSettings settings.AmneziaWg, ipv6Supported bool,
+) amneziawg.Settings {
+	return amneziawg.Settings{
+		Wireguard:       buildWireguardSettings(connection, userSettings.Wireguard, ipv6Supported),
+		JunkPacketCount: *userSettings.JunkPacketCount,
+		JunkPacketMin:   *userSettings.JunkPacketMin,
+		JunkPacketMax:   *userSettings.JunkPacketMax,
+		PaddingS1:       *userSettings.PaddingS1,
+		PaddingS2:       *userSettings.PaddingS2,
+		PaddingS3:       *userSettings.PaddingS3,
+		PaddingS4:       *userSettings.PaddingS4,
+		HeaderH1:        *userSettings.HeaderH1,
+		HeaderH2:        *userSettings.HeaderH2,
+		HeaderH3:        *userSettings.HeaderH3,
+		HeaderH4:        *userSettings.HeaderH4,
+		InitPacketI1:    *userSettings.InitPacketI1,
+		InitPacketI2:    *userSettings.InitPacketI2,
+		InitPacketI3:    *userSettings.InitPacketI3,
+		InitPacketI4:    *userSettings.InitPacketI4,
+		InitPacketI5:    *userSettings.InitPacketI5,
+	}
+}