diff --git a/lib/philomena/bans.ex b/lib/philomena/bans.ex index 8b6daa6e..4b4bdcc8 100644 --- a/lib/philomena/bans.ex +++ b/lib/philomena/bans.ex @@ -4,13 +4,17 @@ defmodule Philomena.Bans do """ import Ecto.Query, warn: false + alias Ecto.Multi alias Philomena.Repo - alias Philomena.UserIps + alias Philomena.Bans.Finder alias Philomena.Bans.Fingerprint + alias Philomena.Bans.SubnetCreator + alias Philomena.Bans.Subnet + alias Philomena.Bans.User @doc """ - Returns the list of fingerprint_bans. + Returns the list of fingerprint bans. ## Examples @@ -23,9 +27,9 @@ defmodule Philomena.Bans do end @doc """ - Gets a single fingerprint. + Gets a single fingerprint ban. - Raises `Ecto.NoResultsError` if the Fingerprint does not exist. + Raises `Ecto.NoResultsError` if the fingerprint ban does not exist. ## Examples @@ -39,7 +43,7 @@ defmodule Philomena.Bans do def get_fingerprint!(id), do: Repo.get!(Fingerprint, id) @doc """ - Creates a fingerprint. + Creates a fingerprint ban. ## Examples @@ -57,7 +61,7 @@ defmodule Philomena.Bans do end @doc """ - Updates a fingerprint. + Updates a fingerprint ban. ## Examples @@ -75,7 +79,7 @@ defmodule Philomena.Bans do end @doc """ - Deletes a Fingerprint. + Deletes a fingerprint ban. ## Examples @@ -91,7 +95,7 @@ defmodule Philomena.Bans do end @doc """ - Returns an `%Ecto.Changeset{}` for tracking fingerprint changes. + Returns an `%Ecto.Changeset{}` for tracking fingerprint ban changes. ## Examples @@ -103,10 +107,8 @@ defmodule Philomena.Bans do Fingerprint.changeset(fingerprint, %{}) end - alias Philomena.Bans.Subnet - @doc """ - Returns the list of subnet_bans. + Returns the list of subnet bans. ## Examples @@ -119,9 +121,9 @@ defmodule Philomena.Bans do end @doc """ - Gets a single subnet. + Gets a single subnet ban. - Raises `Ecto.NoResultsError` if the Subnet does not exist. + Raises `Ecto.NoResultsError` if the subnet ban does not exist. ## Examples @@ -135,7 +137,7 @@ defmodule Philomena.Bans do def get_subnet!(id), do: Repo.get!(Subnet, id) @doc """ - Creates a subnet. + Creates a subnet ban. ## Examples @@ -153,7 +155,7 @@ defmodule Philomena.Bans do end @doc """ - Updates a subnet. + Updates a subnet ban. ## Examples @@ -171,7 +173,7 @@ defmodule Philomena.Bans do end @doc """ - Deletes a Subnet. + Deletes a subnet ban. ## Examples @@ -187,7 +189,7 @@ defmodule Philomena.Bans do end @doc """ - Returns an `%Ecto.Changeset{}` for tracking subnet changes. + Returns an `%Ecto.Changeset{}` for tracking subnet ban changes. ## Examples @@ -199,10 +201,8 @@ defmodule Philomena.Bans do Subnet.changeset(subnet, %{}) end - alias Philomena.Bans.User - @doc """ - Returns the list of user_bans. + Returns the list of user bans. ## Examples @@ -215,9 +215,9 @@ defmodule Philomena.Bans do end @doc """ - Gets a single user. + Gets a single user ban. - Raises `Ecto.NoResultsError` if the User does not exist. + Raises `Ecto.NoResultsError` if the user ban does not exist. ## Examples @@ -231,7 +231,7 @@ defmodule Philomena.Bans do def get_user!(id), do: Repo.get!(User, id) @doc """ - Creates a user. + Creates a user ban. ## Examples @@ -243,31 +243,27 @@ defmodule Philomena.Bans do """ def create_user(creator, attrs \\ %{}) do - %User{banning_user_id: creator.id} - |> User.save_changeset(attrs) - |> Repo.insert() + changeset = + %User{banning_user_id: creator.id} + |> User.save_changeset(attrs) + + Multi.new() + |> Multi.insert(:user_ban, changeset) + |> Multi.run(:subnet_ban, fn _repo, %{user_ban: %{user_id: user_id}} -> + SubnetCreator.create_for_user(creator, user_id, attrs) + end) + |> Repo.transaction() |> case do - {:ok, user_ban} -> - ip = UserIps.get_ip_for_user(user_ban.user_id) - - if ip do - # Automatically create associated IP ban. - ip = UserIps.masked_ip(ip) - - %Subnet{banning_user_id: creator.id, specification: ip} - |> Subnet.save_changeset(attrs) - |> Repo.insert() - end - + {:ok, %{user_ban: user_ban}} -> {:ok, user_ban} - error -> - error + {:error, :user_ban, changeset, _changes} -> + {:error, changeset} end end @doc """ - Updates a user. + Updates a user ban. ## Examples @@ -285,7 +281,7 @@ defmodule Philomena.Bans do end @doc """ - Deletes a User. + Deletes a user ban. ## Examples @@ -301,7 +297,7 @@ defmodule Philomena.Bans do end @doc """ - Returns an `%Ecto.Changeset{}` for tracking user changes. + Returns an `%Ecto.Changeset{}` for tracking user ban changes. ## Examples @@ -314,88 +310,9 @@ defmodule Philomena.Bans do end @doc """ - Returns the first ban, if any, that matches the specified request - attributes. + Returns the first ban, if any, that matches the specified request attributes. """ - def exists_for?(user, ip, fingerprint) do - now = DateTime.utc_now() - - queries = - subnet_query(ip, now) ++ - fingerprint_query(fingerprint, now) ++ - user_query(user, now) - - bans = - queries - |> union_all_queries() - |> Repo.all() - - # Don't return a ban if the user is currently signed in. - case is_nil(user) do - true -> Enum.at(bans, 0) - false -> user_ban(bans) - end - end - - defp fingerprint_query(nil, _now), do: [] - - defp fingerprint_query(fingerprint, now) do - [ - Fingerprint - |> select([f], %{ - reason: f.reason, - valid_until: f.valid_until, - generated_ban_id: f.generated_ban_id, - type: ^"FingerprintBan" - }) - |> where([f], f.enabled and f.valid_until > ^now) - |> where([f], f.fingerprint == ^fingerprint) - ] - end - - defp subnet_query(nil, _now), do: [] - - defp subnet_query(ip, now) do - {:ok, inet} = EctoNetwork.INET.cast(ip) - - [ - Subnet - |> select([s], %{ - reason: s.reason, - valid_until: s.valid_until, - generated_ban_id: s.generated_ban_id, - type: ^"SubnetBan" - }) - |> where([s], s.enabled and s.valid_until > ^now) - |> where(fragment("specification >>= ?", ^inet)) - ] - end - - defp user_query(nil, _now), do: [] - - defp user_query(user, now) do - [ - User - |> select([u], %{ - reason: u.reason, - valid_until: u.valid_until, - generated_ban_id: u.generated_ban_id, - type: ^"UserBan" - }) - |> where([u], u.enabled and u.valid_until > ^now) - |> where([u], u.user_id == ^user.id) - ] - end - - defp union_all_queries([query]), - do: query - - defp union_all_queries([query | rest]), - do: query |> union_all(^union_all_queries(rest)) - - defp user_ban(bans) do - bans - |> Enum.filter(&(&1.type == "UserBan")) - |> Enum.at(0) + def find(user, ip, fingerprint) do + Finder.find(user, ip, fingerprint) end end diff --git a/lib/philomena/bans/finder.ex b/lib/philomena/bans/finder.ex new file mode 100644 index 00000000..f44e1754 --- /dev/null +++ b/lib/philomena/bans/finder.ex @@ -0,0 +1,86 @@ +defmodule Philomena.Bans.Finder do + @moduledoc """ + Helper to find a bans associated with a set of request attributes. + """ + + import Ecto.Query, warn: false + alias Philomena.Repo + + alias Philomena.Bans.Fingerprint + alias Philomena.Bans.Subnet + alias Philomena.Bans.User + + @fingerprint "Fingerprint" + @subnet "Subnet" + @user "User" + + @doc """ + Returns the first ban, if any, that matches the specified request attributes. + """ + def find(user, ip, fingerprint) do + bans = + generate_valid_queries([ + {ip, &subnet_query/2}, + {fingerprint, &fingerprint_query/2}, + {user, &user_query/2} + ]) + |> union_all_queries() + |> Repo.all() + + # Don't return a fingerprint or subnet ban if the user is currently signed in. + case is_nil(user) do + true -> Enum.at(bans, 0) + false -> user_ban(bans) + end + end + + defp query_base(schema, name, now) do + from b in schema, + where: b.enabled and b.valid_until > ^now, + select: %{ + reason: b.reason, + valid_until: b.valid_until, + generated_ban_id: b.generated_ban_id, + type: type(^name, :string) + } + end + + defp fingerprint_query(fingerprint, now) do + Fingerprint + |> query_base(@fingerprint, now) + |> where([f], f.fingerprint == ^fingerprint) + end + + defp subnet_query(ip, now) do + {:ok, inet} = EctoNetwork.INET.cast(ip) + + Subnet + |> query_base(@subnet, now) + |> where(fragment("specification >>= ?", ^inet)) + end + + defp user_query(user, now) do + User + |> query_base(@user, now) + |> where([u], u.user_id == ^user.id) + end + + defp generate_valid_queries(sources) do + now = DateTime.utc_now() + + Enum.flat_map(sources, fn + {nil, _cb} -> [] + {source, cb} -> [cb.(source, now)] + end) + end + + defp union_all_queries([query | rest]) do + Enum.reduce(rest, query, fn q, acc -> union_all(acc, ^q) end) + end + + defp user_ban(bans) do + bans + |> Enum.filter(&(&1.type == @user)) + |> Enum.at(0) + end +end diff --git a/lib/philomena/bans/subnet_creator.ex b/lib/philomena/bans/subnet_creator.ex new file mode 100644 index 00000000..3f54a3c5 --- /dev/null +++ b/lib/philomena/bans/subnet_creator.ex @@ -0,0 +1,27 @@ +defmodule Philomena.Bans.SubnetCreator do + @moduledoc """ + Handles automatic creation of subnet bans for an input user ban. + + This prevents trivial ban evasion with the creation of a new account from the same address. + The user must work around or wait out the subnet ban first. + """ + + alias Philomena.UserIps + alias Philomena.Bans + + @doc """ + Creates a subnet ban for the given user's last known IP address. + + Returns `{:ok, ban}`, `{:ok, nil}`, or `{:error, changeset}`. The return value is + suitable for use as the return value to an `Ecto.Multi.run/3` callback. + """ + def create_for_user(creator, user_id, attrs) do + ip = UserIps.get_ip_for_user(user_id) + + if ip do + Bans.create_subnet(creator, Map.put(attrs, "specification", UserIps.masked_ip(ip))) + else + {:ok, nil} + end + end +end diff --git a/lib/philomena_web/controllers/admin/user_ban_controller.ex b/lib/philomena_web/controllers/admin/user_ban_controller.ex index 24847076..ff6833c0 100644 --- a/lib/philomena_web/controllers/admin/user_ban_controller.ex +++ b/lib/philomena_web/controllers/admin/user_ban_controller.ex @@ -53,9 +53,6 @@ defmodule PhilomenaWeb.Admin.UserBanController do |> moderation_log(details: &log_details/2, data: user_ban) |> redirect(to: ~p"/admin/user_bans") - {:error, :user_ban, changeset, _changes} -> - render(conn, "new.html", changeset: changeset) - {:error, changeset} -> render(conn, "new.html", changeset: changeset) end diff --git a/lib/philomena_web/plugs/api_require_authorization_plug.ex b/lib/philomena_web/plugs/api_require_authorization_plug.ex index 118a59c2..719ccf0b 100755 --- a/lib/philomena_web/plugs/api_require_authorization_plug.ex +++ b/lib/philomena_web/plugs/api_require_authorization_plug.ex @@ -22,7 +22,7 @@ defmodule PhilomenaWeb.ApiRequireAuthorizationPlug do conn |> maybe_unauthorized(user) - |> maybe_forbidden(Bans.exists_for?(user, conn.remote_ip, "NOTAPI")) + |> maybe_forbidden(Bans.find(user, conn.remote_ip, "NOTAPI")) end defp maybe_unauthorized(conn, nil) do diff --git a/lib/philomena_web/plugs/current_ban_plug.ex b/lib/philomena_web/plugs/current_ban_plug.ex index 273a7889..d112fa16 100644 --- a/lib/philomena_web/plugs/current_ban_plug.ex +++ b/lib/philomena_web/plugs/current_ban_plug.ex @@ -20,7 +20,7 @@ defmodule PhilomenaWeb.CurrentBanPlug do user = conn.assigns.current_user ip = conn.remote_ip - ban = Bans.exists_for?(user, ip, fingerprint) + ban = Bans.find(user, ip, fingerprint) Conn.assign(conn, :current_ban, ban) end