Improve custom proxy daemon rpc code and types

3 files changed, 84 insertions, 176 deletions

diff --git a/gui/src/main/daemon-rpc.ts b/gui/src/main/daemon-rpc.ts
index 703ad027cc..531ec80ced 100644
--- a/gui/src/main/daemon-rpc.ts
+++ b/gui/src/main/daemon-rpc.ts
@@ -17,6 +17,7 @@ import {
   ApiAccessMethodSettings,
   AuthFailedError,
   BridgeSettings,
+  BridgesMethod,
   BridgeState,
   BridgeType,
   ConnectionConfig,
@@ -27,6 +28,7 @@ import {
   DaemonEvent,
   DeviceEvent,
   DeviceState,
+  DirectMethod,
   EndpointObfuscationType,
   ErrorState,
   ErrorStateCause,
@@ -82,7 +84,6 @@ const NETWORK_CALL_TIMEOUT = 10000;
 const CHANNEL_STATE_TIMEOUT = 1000 * 60 * 60;
 
 const noConnectionError = new Error('No connection established to daemon');
-const configNotSupported = new Error('Setting custom settings is not supported');
 const invalidErrorStateCause = new Error(
   'VPN_PERMISSION_DENIED is not a valid error state cause on desktop',
 );
@@ -347,51 +348,17 @@ export class DaemonRpc {
   public async setBridgeSettings(bridgeSettings: BridgeSettings): Promise<void> {
     const grpcBridgeSettings = new grpcTypes.BridgeSettings();
 
-    if (bridgeSettings.type === 'custom') {
-      throw configNotSupported;
-    }
-
-    grpcBridgeSettings.setBridgeType(grpcTypes.BridgeSettings.BridgeType.NORMAL);
+    grpcBridgeSettings.setBridgeType(
+      bridgeSettings.type === 'normal'
+        ? grpcTypes.BridgeSettings.BridgeType.NORMAL
+        : grpcTypes.BridgeSettings.BridgeType.CUSTOM,
+    );
 
     const normalSettings = convertToNormalBridgeSettings(bridgeSettings.normal);
     grpcBridgeSettings.setNormal(normalSettings);
 
     if (bridgeSettings.custom) {
-      const customProxy = new grpcTypes.CustomProxy();
-
-      const customSettings = bridgeSettings.custom;
-
-      if ('local' in customSettings) {
-        const local = customSettings.local;
-        const socks5Local = new grpcTypes.Socks5Local();
-        socks5Local.setLocalPort(local.localPort);
-        socks5Local.setRemoteIp(local.remoteIp);
-        socks5Local.setRemotePort(local.remotePort);
-        customProxy.setSocks5local(socks5Local);
-      }
-      if ('remote' in customSettings) {
-        const remote = customSettings.remote;
-        const socks5Remote = new grpcTypes.Socks5Remote();
-        if (remote.auth) {
-          const auth = new grpcTypes.SocksAuth();
-          auth.setUsername(remote.auth.username);
-          auth.setPassword(remote.auth.password);
-          socks5Remote.setAuth(auth);
-        }
-        socks5Remote.setIp(remote.ip);
-        socks5Remote.setPort(remote.port);
-        customProxy.setSocks5remote(socks5Remote);
-      }
-      if ('shadowsocks' in customSettings) {
-        const shadowsocks = customSettings.shadowsocks;
-        const shadowOut = new grpcTypes.Shadowsocks();
-        shadowOut.setCipher(shadowsocks.cipher);
-        shadowOut.setIp(shadowsocks.ip);
-        shadowOut.setPort(shadowsocks.port);
-        shadowOut.setPassword(shadowsocks.password);
-        customProxy.setShadowsocks(shadowOut);
-      }
-
+      const customProxy = convertToCustomProxy(bridgeSettings.custom);
       grpcBridgeSettings.setCustom(customProxy);
     }
 
@@ -1276,41 +1243,8 @@ function convertFromBridgeSettings(bridgeSettings: grpcTypes.BridgeSettings): Br
     ownership,
   };
 
-  let custom = undefined;
-
-  if (bridgeSettingsObject.custom) {
-    const localSettings = bridgeSettingsObject.custom.socks5local;
-    if (localSettings) {
-      custom = {
-        local: {
-          localPort: localSettings.localPort,
-          remoteIp: localSettings.remoteIp,
-          remotePort: localSettings.remotePort,
-        },
-      };
-    }
-    const remoteSettings = bridgeSettingsObject.custom.socks5remote;
-    if (remoteSettings) {
-      custom = {
-        remote: {
-          ip: remoteSettings.ip,
-          port: remoteSettings.port,
-          auth: remoteSettings.auth && { ...remoteSettings.auth },
-        },
-      };
-    }
-    const shadowsocksSettings = bridgeSettingsObject.custom.shadowsocks;
-    if (shadowsocksSettings) {
-      custom = {
-        shadowsocks: {
-          ip: shadowsocksSettings.ip,
-          port: shadowsocksSettings.port,
-          password: shadowsocksSettings.password,
-          cipher: shadowsocksSettings.cipher,
-        },
-      };
-    }
-  }
+  const grpcCustom = bridgeSettings.getCustom();
+  const custom = grpcCustom ? convertFromCustomProxy(grpcCustom) : undefined;
 
   return { type, normal, custom };
 }
@@ -1910,15 +1844,16 @@ function convertFromApiAccessMethodSettings(
 ): ApiAccessMethodSettings {
   const direct = convertFromApiAccessMethodSetting(
     ensureExists(accessMethods.getDirect(), "no 'Direct' access method was found"),
-  );
+  ) as AccessMethodSetting<DirectMethod>;
   const bridges = convertFromApiAccessMethodSetting(
     ensureExists(accessMethods.getMullvadBridges(), "no 'Mullvad Bridges' access method was found"),
-  );
-  const custom =
-    accessMethods
-      .getCustomList()
-      .filter((setting) => setting.hasId() && setting.hasAccessMethod())
-      .map(convertFromApiAccessMethodSetting) ?? [];
+  ) as AccessMethodSetting<BridgesMethod>;
+  const custom = accessMethods
+    .getCustomList()
+    .filter((setting) => setting.hasId() && setting.hasAccessMethod())
+    .map(convertFromApiAccessMethodSetting)
+    // The last filter helps TypeScript infer the custom proxy type.
+    .filter(isCustomProxy);
 
   return {
     direct,
@@ -1927,6 +1862,12 @@ function convertFromApiAccessMethodSettings(
   };
 }
 
+function isCustomProxy(
+  accessMethod: AccessMethodSetting,
+): accessMethod is AccessMethodSetting<CustomProxy> {
+  return accessMethod.type !== 'direct' && accessMethod.type !== 'bridges';
+}
+
 function convertFromApiAccessMethodSetting(
   setting: grpcTypes.AccessMethodSetting,
 ): AccessMethodSetting {
@@ -1948,52 +1889,52 @@ function convertFromAccessMethod(method: grpcTypes.AccessMethod): AccessMethod {
     case grpcTypes.AccessMethod.AccessMethodCase.BRIDGES:
       return { type: 'bridges' };
     case grpcTypes.AccessMethod.AccessMethodCase.CUSTOM: {
-      const proxy = method.getCustom()!;
-      switch (proxy.getProxyMethodCase()) {
-        case grpcTypes.CustomProxy.ProxyMethodCase.SOCKS5LOCAL: {
-          const socks5Local = proxy.getSocks5local()!;
-          return {
-            type: 'socks5-local',
-            remoteIp: socks5Local.getRemoteIp(),
-            remotePort: socks5Local.getRemotePort(),
-            remoteTransportProtocol: convertFromTransportProtocol(
-              socks5Local.getRemoteTransportProtocol(),
-            ),
-            localPort: socks5Local.getLocalPort(),
-          };
-        }
-        case grpcTypes.CustomProxy.ProxyMethodCase.SOCKS5REMOTE: {
-          const socks5Remote = proxy.getSocks5remote()!;
-          const auth = socks5Remote.getAuth();
-          return {
-            type: 'socks5-remote',
-            ip: socks5Remote.getIp(),
-            port: socks5Remote.getPort(),
-            authentication: auth === undefined ? undefined : convertFromSocksAuth(auth),
-          };
-        }
-        case grpcTypes.CustomProxy.ProxyMethodCase.SHADOWSOCKS: {
-          const shadowsocks = proxy.getShadowsocks()!;
-          return {
-            type: 'shadowsocks',
-            ip: shadowsocks.getIp(),
-            port: shadowsocks.getPort(),
-            password: shadowsocks.getPassword(),
-            cipher: shadowsocks.getCipher(),
-          };
-        }
-        case grpcTypes.CustomProxy.ProxyMethodCase.PROXY_METHOD_NOT_SET:
-          throw new Error('Custom method not set, which should always be set');
-      }
-      // This break is required to prevent eslint from complainting about fallthrough, even though
-      // all cases are covered above.
-      break;
+      return convertFromCustomProxy(method.getCustom()!);
     }
     case grpcTypes.AccessMethod.AccessMethodCase.ACCESS_METHOD_NOT_SET:
       throw new Error('Access method not set, which should always be set');
   }
 }
 
+function convertFromCustomProxy(proxy: grpcTypes.CustomProxy): CustomProxy {
+  switch (proxy.getProxyMethodCase()) {
+    case grpcTypes.CustomProxy.ProxyMethodCase.SOCKS5LOCAL: {
+      const socks5Local = proxy.getSocks5local()!;
+      return {
+        type: 'socks5-local',
+        remoteIp: socks5Local.getRemoteIp(),
+        remotePort: socks5Local.getRemotePort(),
+        remoteTransportProtocol: convertFromTransportProtocol(
+          socks5Local.getRemoteTransportProtocol(),
+        ),
+        localPort: socks5Local.getLocalPort(),
+      };
+    }
+    case grpcTypes.CustomProxy.ProxyMethodCase.SOCKS5REMOTE: {
+      const socks5Remote = proxy.getSocks5remote()!;
+      const auth = socks5Remote.getAuth();
+      return {
+        type: 'socks5-remote',
+        ip: socks5Remote.getIp(),
+        port: socks5Remote.getPort(),
+        authentication: auth === undefined ? undefined : convertFromSocksAuth(auth),
+      };
+    }
+    case grpcTypes.CustomProxy.ProxyMethodCase.SHADOWSOCKS: {
+      const shadowsocks = proxy.getShadowsocks()!;
+      return {
+        type: 'shadowsocks',
+        ip: shadowsocks.getIp(),
+        port: shadowsocks.getPort(),
+        password: shadowsocks.getPassword(),
+        cipher: shadowsocks.getCipher(),
+      };
+    }
+    case grpcTypes.CustomProxy.ProxyMethodCase.PROXY_METHOD_NOT_SET:
+      throw new Error('Custom method not set, which should always be set');
+  }
+}
+
 function convertFromSocksAuth(auth: grpcTypes.SocksAuth): SocksAuth {
   return {
     username: auth.getUsername(),
diff --git a/gui/src/renderer/redux/settings/reducers.ts b/gui/src/renderer/redux/settings/reducers.ts
index 210ef38010..e64b0d6323 100644
--- a/gui/src/renderer/redux/settings/reducers.ts
+++ b/gui/src/renderer/redux/settings/reducers.ts
@@ -6,6 +6,7 @@ import {
   BridgeState,
   BridgeType,
   CustomLists,
+  CustomProxy,
   IDnsOptions,
   IpVersion,
   IWireguardEndpointData,
@@ -13,7 +14,6 @@ import {
   ObfuscationSettings,
   ObfuscationType,
   Ownership,
-  ProxySettings,
   RelayEndpointType,
   RelayLocation,
   RelayOverride,
@@ -62,7 +62,7 @@ export type RelaySettingsRedux =
 export type BridgeSettingsRedux = {
   type: BridgeType;
   normal: NormalBridgeSettingsRedux;
-  custom?: ProxySettings;
+  custom?: CustomProxy;
 };
 
 export interface IRelayLocationRelayRedux {
diff --git a/gui/src/shared/daemon-rpc-types.ts b/gui/src/shared/daemon-rpc-types.ts
index e24c124f4c..fb1a88cff6 100644
--- a/gui/src/shared/daemon-rpc-types.ts
+++ b/gui/src/shared/daemon-rpc-types.ts
@@ -352,35 +352,6 @@ export interface IDnsOptions {
   };
 }
 
-export type ProxySettings =
-  | { local: ILocalProxySettings }
-  | { remote: IRemoteProxySettings }
-  | { shadowsocks: IShadowsocksProxySettings };
-
-export interface ILocalProxySettings {
-  localPort: number;
-  remoteIp: string;
-  remotePort: number;
-}
-
-export interface IRemoteProxySettings {
-  ip: string;
-  port: number;
-  auth?: IRemoteProxyAuth;
-}
-
-export interface IRemoteProxyAuth {
-  username: string;
-  password: string;
-}
-
-export interface IShadowsocksProxySettings {
-  ip: string;
-  port: number;
-  password: string;
-  cipher: string;
-}
-
 export interface IAppVersionInfo {
   supported: boolean;
   suggestedUpgrade?: string;
@@ -471,7 +442,7 @@ export type BridgeType = 'normal' | 'custom';
 export interface BridgeSettings {
   type: BridgeType;
   normal: IBridgeConstraints;
-  custom?: ProxySettings;
+  custom?: CustomProxy;
 }
 
 export interface ISocketAddress {
@@ -488,7 +459,7 @@ export interface SocksAuth {
   password: string;
 }
 
-export type Socks5LocalAccessMethod = {
+export type Socks5LocalCustomProxy = {
   type: 'socks5-local';
   remoteIp: string;
   remotePort: number;
@@ -496,14 +467,14 @@ export type Socks5LocalAccessMethod = {
   localPort: number;
 };
 
-export type Socks5RemoteAccessMethod = {
+export type Socks5RemoteCustomProxy = {
   type: 'socks5-remote';
   ip: string;
   port: number;
   authentication?: SocksAuth;
 };
 
-export type ShadowsocksAccessMethod = {
+export type ShadowsocksCustomProxy = {
   type: 'shadowsocks';
   ip: string;
   port: number;
@@ -511,33 +482,29 @@ export type ShadowsocksAccessMethod = {
   cipher: string;
 };
 
-export type CustomProxy =
-  | Socks5LocalAccessMethod
-  | Socks5RemoteAccessMethod
-  | ShadowsocksAccessMethod;
+export type CustomProxy = Socks5LocalCustomProxy | Socks5RemoteCustomProxy | ShadowsocksCustomProxy;
+export type NamedCustomProxy = CustomProxy & { name: string };
 
-export type AccessMethod =
-  | {
-      type: 'direct';
-    }
-  | {
-      type: 'bridges';
-    }
-  | CustomProxy;
+export type DirectMethod = { type: 'direct' };
+export type BridgesMethod = { type: 'bridges' };
+export type AccessMethod = DirectMethod | BridgesMethod | CustomProxy;
 
-export type NewAccessMethodSetting = AccessMethod & {
-  name: string;
+export type NamedAccessMethod<T extends AccessMethod> = T & { name: string };
+
+export type NewAccessMethodSetting<T extends AccessMethod = AccessMethod> = NamedAccessMethod<T> & {
   enabled: boolean;
 };
 
-export type AccessMethodSetting = NewAccessMethodSetting & {
+export type AccessMethodSetting<
+  T extends AccessMethod = AccessMethod
+> = NewAccessMethodSetting<T> & {
   id: string;
 };
 
 export type ApiAccessMethodSettings = {
-  direct: AccessMethodSetting;
-  mullvadBridges: AccessMethodSetting;
-  custom: Array<AccessMethodSetting>;
+  direct: AccessMethodSetting<DirectMethod>;
+  mullvadBridges: AccessMethodSetting<BridgesMethod>;
+  custom: Array<AccessMethodSetting<CustomProxy>>;
 };
 
 export interface RelayOverride {