Add connection manager (to be fully fledged peer database)

3 files changed, 69 insertions, 17 deletions

diff --git a/lib/net/manager.ex b/lib/net/manager.ex
new file mode 100644
index 0000000..e5eb12d
--- /dev/null
+++ b/lib/net/manager.ex
@@ -0,0 +1,60 @@
+defmodule SNet.Manager do
+  use GenServer
+
+  def start_link(my_port) do
+    GenServer.start_link(__MODULE__, my_port, name: __MODULE__)
+  end
+
+  def init(my_port) do
+    state = %{
+              peers: %{},
+              my_port: my_port
+            }
+    {:ok, state}
+  end
+
+  def handle_cast({:peer_up, pk, pid, addr, ip}, state) do
+    new_peers = Map.put(state.peers, pk, {pid, addr, ip})
+    new_state = %{ state | peers: new_peers }
+    {:noreply, new_state}
+  end
+
+  def handle_cast({:peer_down, pk, addr, ip}, state) do
+    new_peers = Map.put(state.peers, pk, {nil, addr, ip})
+    new_state = %{ state | peers: new_peers }
+    {:noreply, new_state}
+  end
+
+  def handle_cast({:add_peer, ip, port}, state) do
+    add_peer(ip, port, state.my_port)
+    {:noreply, state}
+  end
+
+  def handle_cast({:try_connect, pk_list}, state) do
+    for pk <- pk_list do
+      case state.peers[pk] do
+        {nil, ip, port} -> add_peer(ip, port)
+        _ -> nil
+      end
+    end
+    {:noreply, state}
+  end
+
+  def handle_call({:get_connections, pk_list}, state) do
+    pid_list = (for pk <- pk_list, Map.has_key?(state.peers, pk), do: state.peers[pk])
+    |> Enum.map(fn {pid, _, _} -> pid end)
+    |> Enum.filter(&(&1 != nil))
+    {:ok, pid_list, state}
+  end
+
+  def add_peer(ip, port) do
+    GenServer.cast(__MODULE__, {:add_peer, ip, port})
+  end
+
+  def add_peer(ip, port, my_port) do
+    {:ok, client} = :gen_tcp.connect(ip, port, [:binary, packet: 2, active: false])
+    {:ok, pid} = DynamicSupervisor.start_child(SNet.ConnSupervisor, {SNet.TCPConn, %{socket: client, my_port: my_port}})
+    :ok = :gen_tcp.controlling_process(client, pid)
+    pid
+  end
+end
diff --git a/lib/net/tcpconn.ex b/lib/net/tcpconn.ex
index 5d6c912..301e931 100644
--- a/lib/net/tcpconn.ex
+++ b/lib/net/tcpconn.ex
@@ -25,11 +25,10 @@ defmodule SNet.TCPConn do
     {:ok, challenge} = Salty.Random.buf 32
 
     # Exchange public keys and challenge
-    :gen_tcp.send(socket, srv_pkey <> sess_pkey <> challenge)  
+    hello = {srv_pkey, sess_pkey, challenge, state.my_port}
+    :gen_tcp.send(socket, :erlang.term_to_binary hello)  
     {:ok, pkt} = :gen_tcp.recv(socket, 0)
-    cli_pkey = binary_part(pkt, 0, Sign.publickeybytes)
-    cli_sess_pkey = binary_part(pkt, Sign.publickeybytes, Box.publickeybytes)
-    cli_challenge = binary_part(pkt, Sign.publickeybytes + Box.publickeybytes, 32)
+    {cli_pkey, cli_sess_pkey, cli_challenge, his_port} = :erlang.binary_to_term(pkt, [:safe])
 
     # Do challenge and check their challenge
     {:ok, cli_challenge_sign} = Sign.sign_detached(cli_challenge, srv_skey)
@@ -54,6 +53,7 @@ defmodule SNet.TCPConn do
         addr: addr,
         port: port
       }
+    GenServer.cast(SNet.Manager, {:peer_up, self(), cli_pkey, addr, his_port})
     Logger.info "New peer: #{print_id state} at #{inspect addr}:#{port}"
 
     GenServer.cast(self(), :init_push)
@@ -98,6 +98,7 @@ defmodule SNet.TCPConn do
 
   def handle_info({:tcp_closed, _socket}, state) do
     Logger.info "Disconnected: #{print_id state} at #{inspect state.addr}:#{state.port}"
+    GenServer.cast(SNet.Manager, {:peer_down, state.his_pkey, state.addr, state.port})
     exit(:normal)
   end
 
diff --git a/lib/net/tcpserver.ex b/lib/net/tcpserver.ex
index e5ee996..7c758c1 100644
--- a/lib/net/tcpserver.ex
+++ b/lib/net/tcpserver.ex
@@ -6,7 +6,6 @@ defmodule SNet.TCPServer do
     Task.start_link(__MODULE__, :accept, [port])
   end
 
-
   @doc """
   Starts accepting connections on the given `port`.
   """
@@ -14,22 +13,14 @@ defmodule SNet.TCPServer do
     {:ok, socket} = :gen_tcp.listen(port,
                       [:binary, packet: 2, active: false, reuseaddr: true])
     Logger.info "Accepting connections on port #{port}"
-    loop_acceptor(socket)
+    loop_acceptor(socket, port)
   end
 
-  defp loop_acceptor(socket) do
+  defp loop_acceptor(socket, my_port) do
     {:ok, client} = :gen_tcp.accept(socket)
-    {:ok, pid} = DynamicSupervisor.start_child(SNet.ConnSupervisor, {SNet.TCPConn, %{socket: client}})
+    {:ok, pid} = DynamicSupervisor.start_child(SNet.ConnSupervisor, {SNet.TCPConn, %{socket: client, my_port: my_port}})
     :ok = :gen_tcp.controlling_process(client, pid)
-    loop_acceptor(socket)
+    loop_acceptor(socket, my_port)
   end
-
-  def add_peer(ip, port) do
-    {:ok, client} = :gen_tcp.connect(ip, port, [:binary, packet: 2, active: false])
-    {:ok, pid} = DynamicSupervisor.start_child(SNet.ConnSupervisor, {SNet.TCPConn, %{socket: client}})
-    :ok = :gen_tcp.controlling_process(client, pid)
-    pid
-  end
-
 end