[federation] implement resolve endpoint

apps/boruta_federation/lib/boruta_federation/federation_entities.ex

@@ -14,7 +14,12 @@ defmodule BorutaFederation.FederationEntities do
 
   @spec get_entity(id :: Ecto.UUID.t()) :: federation_entity :: FederationEntity.t() | nil
   def get_entity(id) do
-    Repo.get(FederationEntity, id)
+    case Ecto.UUID.cast(id) do
+      {:ok, _} ->
+        Repo.get(FederationEntity, id)
+      _ ->
+        nil
+    end
   end
 
   @spec create_entity(

apps/boruta_federation/lib/boruta_federation/openid_federation.ex

@@ -0,0 +1,43 @@
+defmodule BorutaFederation.OpenidFederationApplication do
+  @callback resolve_success(context :: any, federation_entity_statement :: String.t()) :: any()
+  @callback resolve_failure(context :: any, error :: Boruta.Oauth.Error.t()) :: any()
+end
+
+defmodule BorutaFederation.OpenidFederation do
+  alias Boruta.Oauth.Error
+  alias BorutaFederation.FederationEntities
+  alias BorutaFederation.TrustChains
+
+  @type resolve_params :: %{
+          sub: String.t(),
+          anchor: String.t()
+        }
+
+  @spec resolve(context :: any(), resolve_params :: resolve_params(), module :: atom()) :: any()
+  def resolve(context, resolve_params, module) do
+    case FederationEntities.get_entity(resolve_params[:sub]) do
+      nil ->
+        error = %Error{
+          status: :bad_request,
+          error: :invalid_request,
+          error_description: "Federation entity could not be found."
+        }
+        module.resolve_failure(context, error)
+
+      entity ->
+        case TrustChains.generate_statement(entity) do
+          {:ok, statement} ->
+            module.resolve_success(context, statement)
+
+          {:error, error} ->
+            error = %Error{
+              status: :bad_request,
+              error: :invalid_request,
+              error_description: "Could not generate federation entity statement #{error}."
+            }
+
+            module.resolve_failure(context, error)
+        end
+    end
+  end
+end

apps/boruta_federation/lib/boruta_federation/trust_chains.ex

@@ -16,12 +16,12 @@ defmodule BorutaFederation.TrustChains do
       now = :os.system_time(:second)
 
       payload = %{
-        "iss" => issuer(),
-        "sub" => entity.id,
-        "iat" => now,
         "exp" => now + entity.trust_chain_statement_ttl,
+        "iat" => now,
+        "iss" => issuer(),
         "jwks" => jwks,
         "metadata" => metadata,
+        "sub" => entity.id,
         "trust_marks" => trust_marks
       }
 

apps/boruta_federation/lib/boruta_federation_web/controllers/resolve_controller.ex

@@ -0,0 +1,32 @@
+defmodule BorutaFederationWeb.ResolveController do
+  @behaviour BorutaFederation.OpenidFederationApplication
+
+  alias BorutaFederationWeb.ErrorView
+  use BorutaFederationWeb, :controller
+
+  alias BorutaFederation.OpenidFederation
+
+  def resolve(conn, params) do
+    resolve_params = %{
+      sub: params["sub"],
+      anchor: params["anchor"]
+    }
+
+    OpenidFederation.resolve(conn, resolve_params, __MODULE__)
+  end
+
+  @impl BorutaFederation.OpenidFederationApplication
+  def resolve_success(conn, federation_entity_statement) do
+    conn
+    |> put_resp_header("content-type", "application/resolve-response+jwt")
+    |> send_resp(200, federation_entity_statement)
+  end
+
+  @impl BorutaFederation.OpenidFederationApplication
+  def resolve_failure(conn, error) do
+    conn
+    |> put_status(error.status)
+    |> put_view(ErrorView)
+    |> render("error.json", error: error)
+  end
+end

apps/boruta_federation/lib/boruta_federation_web/router.ex

@@ -11,8 +11,9 @@ defmodule BorutaFederationWeb.Router do
   end
 
   scope "/", BorutaFederationWeb do
-    pipe_through :browser
+    pipe_through :api
 
     get "/", PageController, :index
+    get "/resolve", ResolveController, :resolve
   end
 end

apps/boruta_federation/lib/boruta_federation_web/views/error_view.ex

@@ -13,4 +13,11 @@ defmodule BorutaFederationWeb.ErrorView do
   def template_not_found(template, _assigns) do
     Phoenix.Controller.status_message_from_template(template)
   end
+
+  def render("error.json", %{error: error}) do
+    %{
+      error: error.error,
+      error_description: error.error_description
+    }
+  end
 end

apps/boruta_federation/test/boruta_federation/trust_chains_test.exs

@@ -3,6 +3,7 @@ defmodule BorutaFederation.TrustChainsTest do
 
   import BorutaFederation.Factory
 
+  alias BorutaFederation.FederationEntities.LeafEntity.Token
   alias BorutaFederation.TrustChains
 
   describe "generate_statement/1" do
@@ -11,6 +12,29 @@ defmodule BorutaFederation.TrustChainsTest do
 
       assert {:ok, statement} = TrustChains.generate_statement(entity)
       assert statement
+
+      entity_id = entity.id
+
+      assert {:ok,
+              %{
+                "exp" => exp,
+                "iat" => iat,
+                "iss" => "http://localhost:4000",
+                "jwks" => [jwk],
+                "metadata" => %{"openid_provider" => %{"issuer" => "http://localhost:4000"}},
+                "sub" => ^entity_id,
+                "trust_marks" => [trust_mark]
+              }} = Joken.peek_claims(statement)
+
+      signer =
+        Joken.Signer.create(entity.trust_chain_statement_alg, %{
+          "pem" => JOSE.JWK.from_map(jwk) |> JOSE.JWK.to_pem() |> elem(1)
+        })
+
+      assert {:ok, _} = Token.verify_and_validate(statement, signer)
+      assert {:ok, _} = Token.verify_and_validate(trust_mark, signer)
+      assert iat
+      assert exp
     end
   end
 end

apps/boruta_federation/test/boruta_federation_web/controllers/resolve_controller_test.exs

@@ -0,0 +1,47 @@
+defmodule BorutaFederationWeb.ResolveControllerTest do
+  use BorutaFederationWeb.ConnCase
+
+  import BorutaFederation.Factory
+
+  alias BorutaFederation.FederationEntities.LeafEntity.Token
+
+  describe "GET /resolve" do
+    test "retruns not found", %{conn: conn} do
+      conn = get(conn, Routes.resolve_path(conn, :resolve, %{sub: "sub", anchor: "anchor"}))
+      assert json_response(conn, 400) == %{
+        "error" => "invalid_request",
+        "error_description" => "Federation entity could not be found."
+      }
+    end
+
+    test "retruns a statement", %{conn: conn} do
+      entity = insert(:entity)
+
+      conn = get(conn, Routes.resolve_path(conn, :resolve, %{sub: entity.id, anchor: "anchor"}))
+      assert statement = response(conn, 200)
+
+      entity_id = entity.id
+
+      assert {:ok,
+              %{
+                "exp" => exp,
+                "iat" => iat,
+                "iss" => "http://localhost:4000",
+                "jwks" => [jwk],
+                "metadata" => %{"openid_provider" => %{"issuer" => "http://localhost:4000"}},
+                "sub" => ^entity_id,
+                "trust_marks" => [trust_mark]
+              }} = Joken.peek_claims(statement)
+
+      signer =
+        Joken.Signer.create(entity.trust_chain_statement_alg, %{
+          "pem" => JOSE.JWK.from_map(jwk) |> JOSE.JWK.to_pem() |> elem(1)
+        })
+
+      assert {:ok, _} = Token.verify_and_validate(statement, signer)
+      assert {:ok, _} = Token.verify_and_validate(trust_mark, signer)
+      assert iat
+      assert exp
+    end
+  end
+end