src/couch/src/couch_password_hasher.erl

% Licensed under the Apache License, Version 2.0 (the "License"); you may not
% use this file except in compliance with the License. You may obtain a copy of
% the License at
%
%   http://www.apache.org/licenses/LICENSE-2.0
%
% Unless required by applicable law or agreed to in writing, software
% distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
% WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
% License for the specific language governing permissions and limitations under
% the License.

-module(couch_password_hasher).

-behaviour(gen_server).

-include_lib("couch/include/couch_db.hrl").

-export([start_link/0]).
-export([
    init/1,
    handle_call/3,
    handle_cast/2,
    code_change/3
]).

-export([hash/1]).

-record(state, {}).

%%%===================================================================
%%% Public functions
%%%===================================================================

-spec hash(Persist :: boolean()) -> Reply :: term().
hash(Persist) ->
    gen_server:cast(?MODULE, {hash_passwords, Persist}).

%%%===================================================================
%%% Spawning and gen_server implementation
%%%===================================================================

start_link() ->
    gen_server:start_link({local, ?MODULE}, ?MODULE, [], []).

init(_Args) ->
    hash_admin_passwords(true),
    {ok, #state{}}.

handle_call(Msg, _From, #state{} = State) ->
    {stop, {invalid_call, Msg}, {invalid_call, Msg}, State}.

handle_cast({hash_passwords, Persist}, State) ->
    hash_admin_passwords(Persist),
    {noreply, State};
handle_cast(Msg, State) ->
    {stop, {invalid_cast, Msg}, State}.

code_change(_OldVsn, #state{} = State, _Extra) ->
    {ok, State}.

%%%===================================================================
%%% Internal functions
%%%===================================================================

hash_admin_passwords(Persist) ->
    lists:foreach(
        fun({User, ClearPassword}) ->
            HashedPassword = couch_passwords:hash_admin_password(ClearPassword),
            config:set("admins", User, ?b2l(HashedPassword), Persist)
        end,
        couch_passwords:get_unhashed_admins()
    ).