Merge pull request #2 from Simponic/erlang_ssh_server

Erlang ssh server #2

3 files changed, 87 insertions, 21 deletions

diff --git a/lib/chessh/ssh/cli.ex b/lib/chessh/ssh/cli.ex
new file mode 100644
index 0000000..71d789b
--- /dev/null
+++ b/lib/chessh/ssh/cli.ex
@@ -0,0 +1,26 @@
+defmodule Chessh.SSH.Cli do
+  @behaviour :ssh_server_channel
+
+  def init(_args) do
+    {:ok, %{}}
+  end
+
+  def handle_msg(_message, state) do
+    {:ok, state}
+  end
+
+  def handle_ssh_msg(
+        {:ssh_cm, _connection_handler, {:exit_signal, channel_id, _signal, _err, _lang}},
+        state
+      ) do
+    {:stop, channel_id, state}
+  end
+
+  def handle_ssh_msg(_message, state) do
+    {:ok, state}
+  end
+
+  def terminate(_reason, _state) do
+    :ok
+  end
+end
diff --git a/lib/chessh/ssh/daemon.ex b/lib/chessh/ssh/daemon.ex
index 9f17f75..b341833 100644
--- a/lib/chessh/ssh/daemon.ex
+++ b/lib/chessh/ssh/daemon.ex
@@ -1,6 +1,10 @@
 defmodule Chessh.SSH.Daemon do
+  alias Chessh.{Repo, PlayerSession, Utils}
   alias Chessh.Auth.PasswordAuthenticator
   use GenServer
+  import Ecto.Query
+
+  require Logger
 
   def start_link(_) do
     GenServer.start_link(__MODULE__, %{
@@ -13,33 +17,33 @@ defmodule Chessh.SSH.Daemon do
     {:ok, state}
   end
 
-  def pwd_authenticate(username, password) do
-    # TODO - check concurrent sessions
-    PasswordAuthenticator.authenticate(
-      String.Chars.to_string(username),
-      String.Chars.to_string(password)
-    )
-  end
-
-  def pwd_authenticate(username, password, inet) do
+  def pwd_authenticate(username, password, {ip, _port}) do
     [jail_timeout_ms, jail_attempt_threshold] =
       Application.get_env(:chessh, RateLimits)
       |> Keyword.take([:jail_timeout_ms, :jail_attempt_threshold])
       |> Keyword.values()
 
-    {ip, _port} = inet
     rateId = "failed_password_attempts:#{Enum.join(Tuple.to_list(ip), ".")}"
 
-    if pwd_authenticate(username, password) do
-      true
-    else
-      case Hammer.check_rate_inc(rateId, jail_timeout_ms, jail_attempt_threshold, 1) do
-        {:allow, _count} ->
-          false
+    case PasswordAuthenticator.authenticate(
+           String.Chars.to_string(username),
+           String.Chars.to_string(password)
+         ) do
+      false ->
+        case Hammer.check_rate_inc(rateId, jail_timeout_ms, jail_attempt_threshold, 1) do
+          {:allow, _count} ->
+            false
+
+          {:deny, _limit} ->
+            :disconnect
+        end
 
-        {:deny, _limit} ->
-          :disconnect
-      end
+      x ->
+        if PlayerSession.player_within_concurrent_sessions_and_satisfies(username, fn _player ->
+             x
+           end),
+           do: true,
+           else: :disconnect
     end
   end
 
@@ -53,10 +57,13 @@ defmodule Chessh.SSH.Daemon do
 
     case :ssh.daemon(
            port,
+           # shell: fn _username, _peer -> Process.sleep(5000) end,
            system_dir: key_dir,
            pwdfun: &pwd_authenticate/4,
            key_cb: Chessh.SSH.ServerKey,
-           #          disconnectfun: 
+           ssh_cli: {Chessh.SSH.Cli, []},
+           #           connectfun: &on_connect/3,
+           disconnectfun: &on_disconnect/1,
            id_string: :random,
            subsystems: [],
            parallel_login: true,
@@ -74,4 +81,32 @@ defmodule Chessh.SSH.Daemon do
   end
 
   def handle_info(_, state), do: {:noreply, state}
+
+  #  defp on_connect(username, _inet, _method) do
+  #    Logger.debug("#{inspect(self())} connected and is authenticated as #{username}")
+  #
+  #    case Repo.get_by(Player, username: String.Chars.to_string(username)) do
+  #      nil ->
+  #        nil
+  #
+  #      player ->
+  #        Repo.insert(%PlayerSession{
+  #          login: DateTime.utc_now(),
+  #          node_id: System.fetch_env!("NODE_ID"),
+  #          player: player,
+  #          process: pid_to_str(self())
+  #        })
+  #    end
+  #  end
+
+  defp on_disconnect(_reason) do
+    Logger.debug("#{inspect(self())} disconnected")
+
+    Repo.delete_all(
+      from(p in PlayerSession,
+        where: p.node_id == ^System.fetch_env!("NODE_ID"),
+        where: p.process == ^Utils.pid_to_str(self())
+      )
+    )
+  end
 end
diff --git a/lib/chessh/ssh/server_key.ex b/lib/chessh/ssh/server_key.ex
index 72a4fbb..5252624 100644
--- a/lib/chessh/ssh/server_key.ex
+++ b/lib/chessh/ssh/server_key.ex
@@ -1,9 +1,14 @@
 defmodule Chessh.SSH.ServerKey do
+  alias Chessh.PlayerSession
   alias Chessh.Auth.KeyAuthenticator
+
   @behaviour :ssh_server_key_api
 
   def is_auth_key(key, username, _daemon_options) do
-    KeyAuthenticator.authenticate(username, key)
+    PlayerSession.player_within_concurrent_sessions_and_satisfies(
+      username,
+      &KeyAuthenticator.authenticate(&1, key)
+    )
   end
 
   def host_key(algorithm, daemon_options) do