diff -r 7732013ce64c -r c5a6e8566425 rust/hedgewars-server/src/handlers/inanteroom.rs
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/rust/hedgewars-server/src/handlers/inanteroom.rs	Tue May 28 19:04:18 2019 +0300
@@ -0,0 +1,148 @@
+use mio;
+
+use crate::{
+    protocol::messages::{
+        HWProtocolMessage::LoadRoom,
+        HWProtocolMessage,
+        HWServerMessage::*},
+    core::{
+        client::HWClient,
+        server::{HWServer, HWAnteClient, HWAnteroom},
+        types::ClientId
+    },
+    utils::is_name_illegal
+};
+
+use log::*;
+#[cfg(feature = "official-server")]
+use openssl::sha::sha1;
+use std::{
+    fmt::{Formatter, LowerHex},
+    num::NonZeroU16,
+};
+
+pub enum LoginResult {
+    Unchanged,
+    Complete,
+    Exit,
+}
+
+fn completion_result<'a, I>(
+    mut other_clients: I,
+    client: &mut HWAnteClient,
+    response: &mut super::Response,
+) -> LoginResult
+where
+    I: Iterator<Item = (ClientId, &'a HWClient)>,
+{
+    let has_nick_clash =
+        other_clients.any(|(_, c)| !c.is_checker() && c.nick == *client.nick.as_ref().unwrap());
+
+    if has_nick_clash {
+        if client.protocol_number.unwrap().get() < 38 {
+            response.add(Bye("User quit: Nickname is already in use".to_string()).send_self());
+            LoginResult::Exit
+        } else {
+            client.nick = None;
+            response.add(Notice("NickAlreadyInUse".to_string()).send_self());
+            LoginResult::Unchanged
+        }
+    } else {
+        #[cfg(feature = "official-server")]
+        {
+            response.add(AskPassword(client.server_salt.clone()).send_self());
+            LoginResult::Unchanged
+        }
+
+        #[cfg(not(feature = "official-server"))]
+        {
+            LoginResult::Complete
+        }
+    }
+}
+
+pub fn handle(
+    server: &mut HWServer,
+    client_id: ClientId,
+    response: &mut super::Response,
+    message: HWProtocolMessage,
+) -> LoginResult {
+    match message {
+        HWProtocolMessage::Quit(_) => {
+            response.add(Bye("User quit".to_string()).send_self());
+            LoginResult::Exit
+        }
+        HWProtocolMessage::Nick(nick) => {
+            let client = &mut server.anteroom.clients[client_id];
+
+            if client.nick.is_some() {
+                response.add(Error("Nickname already provided.".to_string()).send_self());
+                LoginResult::Unchanged
+            } else if is_name_illegal(&nick) {
+                response.add(Bye("Illegal nickname! Nicknames must be between 1-40 characters long, must not have a trailing or leading space and must not have any of these characters: $()*+?[]^{|}".to_string()).send_self());
+                LoginResult::Exit
+            } else {
+                client.nick = Some(nick.clone());
+                response.add(Nick(nick).send_self());
+
+                if client.protocol_number.is_some() {
+                    completion_result(server.clients.iter(), client, response)
+                } else {
+                    LoginResult::Unchanged
+                }
+            }
+        }
+        HWProtocolMessage::Proto(proto) => {
+            let client = &mut server.anteroom.clients[client_id];
+            if client.protocol_number.is_some() {
+                response.add(Error("Protocol already known.".to_string()).send_self());
+                LoginResult::Unchanged
+            } else if proto == 0 {
+                response.add(Error("Bad number.".to_string()).send_self());
+                LoginResult::Unchanged
+            } else {
+                client.protocol_number = NonZeroU16::new(proto);
+                response.add(Proto(proto).send_self());
+
+                if client.nick.is_some() {
+                    completion_result(server.clients.iter(), client, response)
+                } else {
+                    LoginResult::Unchanged
+                }
+            }
+        }
+        #[cfg(feature = "official-server")]
+        HWProtocolMessage::Password(hash, salt) => {
+            let client = &server.anteroom.clients[client_id];
+
+            if let (Some(nick), Some(protocol)) = (client.nick.as_ref(), client.protocol_number) {
+                response.request_io(super::IoTask::GetAccount {
+                    nick: nick.clone(),
+                    protocol: protocol.get(),
+                    server_salt: client.server_salt.clone(),
+                    client_salt: salt,
+                    password_hash: hash,
+                });
+            };
+
+            LoginResult::Unchanged
+        }
+        #[cfg(feature = "official-server")]
+        HWProtocolMessage::Checker(protocol, nick, password) => {
+            let client = &mut server.anteroom.clients[client_id];
+            if protocol == 0 {
+                response.add(Error("Bad number.".to_string()).send_self());
+                LoginResult::Unchanged
+            } else {
+                client.protocol_number = NonZeroU16::new(protocol);
+                client.nick = Some(nick);
+                client.is_checker = true;
+                LoginResult::Complete
+            }
+        }
+        _ => {
+            warn!("Incorrect command in logging-in state");
+            LoginResult::Unchanged
+        }
+    }
+}