ntf server: only use SOCKS proxy for servers without public address (#1314)

Author: epoberezkin

src/Simplex/Messaging/Notifications/Server/Main.hs

@@ -16,7 +16,7 @@ import qualified Data.Text as T
 import qualified Data.Text.IO as T
 import Network.Socket (HostName)
 import Options.Applicative
-import Simplex.Messaging.Client (NetworkConfig (..), ProtocolClientConfig (..), SocksMode (..), defaultNetworkConfig)
+import Simplex.Messaging.Client (HostMode (..), NetworkConfig (..), ProtocolClientConfig (..), SocksMode (..), defaultNetworkConfig)
 import Simplex.Messaging.Client.Agent (SMPClientAgentConfig (..), defaultSMPClientAgentConfig)
 import qualified Simplex.Messaging.Crypto as C
 import Simplex.Messaging.Notifications.Server (runNtfServer)
@@ -26,6 +26,7 @@ import Simplex.Messaging.Notifications.Transport (supportedNTFHandshakes, suppor
 import Simplex.Messaging.Protocol (ProtoServerWithAuth (..), pattern NtfServer)
 import Simplex.Messaging.Server.CLI
 import Simplex.Messaging.Server.Expiration
+import Simplex.Messaging.Server.Main (textToHostMode)
 import Simplex.Messaging.Transport (simplexMQVersion)
 import Simplex.Messaging.Transport.Client (TransportHost (..))
 import Simplex.Messaging.Transport.Server (TransportServerConfig (..), defaultTransportServerConfig)
@@ -92,6 +93,10 @@ ntfServerCLI cfgPath logPath =
             <> "websockets: off\n\n\
                \[SUBSCRIBER]\n\
                \# Network configuration for notification server client.\n\
+               \# `host_mode` can be 'public' (default) or 'onion'.\n\
+               \# It defines prefferred hostname for destination servers with multiple hostnames.\n\
+               \# host_mode: public\n\
+               \# required_host_mode: off\n\n\
                \# SOCKS proxy port for subscribing to SMP servers.\n\
                \# You may need a separate instance of SOCKS proxy for incoming single-hop requests.\n\
                \# socks_proxy: localhost:9050\n\n\
@@ -134,6 +139,8 @@ ntfServerCLI cfgPath logPath =
                             defaultNetworkConfig
                               { socksProxy = either error id <$!> strDecodeIni "SUBSCRIBER" "socks_proxy" ini,
                                 socksMode = maybe SMOnion (either error id) $! strDecodeIni "SUBSCRIBER" "socks_mode" ini,
+                                hostMode = either (const HMPublic) textToHostMode $ lookupValue "SUBSCRIBER" "host_mode" ini,
+                                requiredHostMode = fromMaybe False $ iniOnOff "SUBSCRIBER" "required_host_mode" ini,
                                 smpPingInterval = 60_000_000 -- 1 minutes
                               }
                         },

src/Simplex/Messaging/Server/Main.hs

@@ -318,11 +318,6 @@ smpServerCLI_ generateSite serveStaticFiles cfgPath logPath =
               serverClientConcurrency = readIniDefault defaultProxyClientConcurrency "PROXY" "client_concurrency" ini,
               information = serverPublicInfo ini
             }
-        textToHostMode :: Text -> HostMode
-        textToHostMode = \case
-          "public" -> HMPublic
-          "onion" -> HMOnionViaSocks
-          s -> error . T.unpack $ "Invalid host_mode: " <> s
         textToOwnServers :: Text -> [ByteString]
         textToOwnServers = map encodeUtf8 . T.words
 
@@ -346,6 +341,12 @@ smpServerCLI_ generateSite serveStaticFiles cfgPath logPath =
           where
             isOnion = \case THOnionHost _ -> True; _ -> False
 
+textToHostMode :: Text -> HostMode
+textToHostMode = \case
+  "public" -> HMPublic
+  "onion" -> HMOnionViaSocks
+  s -> error . T.unpack $ "Invalid host_mode: " <> s
+
 data EmbeddedWebParams = EmbeddedWebParams
   { webStaticPath :: FilePath,
     webHttpPort :: Maybe Int,