Add base CAPTCHA support (currently only kocaptcha)

1 files changed, 68 insertions, 0 deletions

diff --git a/lib/pleroma/captcha.ex b/lib/pleroma/captcha.ex
new file mode 100644
index 000000000..31f3bc797
--- /dev/null
+++ b/lib/pleroma/captcha.ex
@@ -0,0 +1,68 @@
+defmodule Pleroma.Captcha do
+  use GenServer
+
+  @ets __MODULE__.Ets
+  @ets_options [:ordered_set, :private, :named_table, {:read_concurrency, true}]
+
+
+  @doc false
+  def start_link() do
+    GenServer.start_link(__MODULE__, [], name: __MODULE__)
+  end
+
+
+  @doc false
+  def init(_) do
+    @ets = :ets.new(@ets, @ets_options)
+
+    {:ok, nil}
+  end
+
+  def new() do
+    GenServer.call(__MODULE__, :new)
+  end
+
+  def validate(token, captcha) do
+    GenServer.call(__MODULE__, {:validate, token, captcha})
+  end
+
+  @doc false
+  def handle_call(:new, _from, state) do
+    method = Pleroma.Config.get!([__MODULE__, :method])
+
+    case method do
+      __MODULE__.Kocaptcha ->
+        endpoint = Pleroma.Config.get!([method, :endpoint])
+        case HTTPoison.get(endpoint <> "/new") do
+          {:error, _} ->
+            %{error: "Kocaptcha service unavailable"}
+          {:ok, res} ->
+            json_resp = Poison.decode!(res.body)
+
+            token = json_resp["token"]
+
+            true = :ets.insert(@ets, {token, json_resp["md5"]})
+
+            {
+              :reply,
+              %{type: :kocaptcha, token: token, url: endpoint <> json_resp["url"]},
+              state
+            }
+        end
+    end
+  end
+
+  @doc false
+  def handle_call({:validate, token, captcha}, _from, state) do
+    with false <- is_nil(captcha),
+         [{^token, saved_md5}] <- :ets.lookup(@ets, token),
+         true <- (:crypto.hash(:md5, captcha) |> Base.encode16) == String.upcase(saved_md5) do
+      # Clear the saved value
+      :ets.delete(@ets, token)
+
+      {:reply, true, state}
+    else
+      e -> IO.inspect(e); {:reply, false, state}
+    end
+  end
+end