emqx/apps/emqx_authz/src/emqx_authz_postgresql.erl
zhanghongtong fa467d0741 chore(authz): rename pgsql to postgresql
Signed-off-by: zhanghongtong <rory-z@outlook.com>
2021-09-17 09:16:38 +08:00

116 lines
4.2 KiB
Erlang

%%--------------------------------------------------------------------
%% Copyright (c) 2020-2021 EMQ Technologies Co., Ltd. All Rights Reserved.
%%
%% 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(emqx_authz_postgresql).
-include("emqx_authz.hrl").
-include_lib("emqx/include/emqx.hrl").
-include_lib("emqx/include/logger.hrl").
%% AuthZ Callbacks
-export([ description/0
, parse_query/1
, authorize/4
]).
-ifdef(TEST).
-compile(export_all).
-compile(nowarn_export_all).
-endif.
description() ->
"AuthZ with postgresql".
parse_query(undefined) ->
undefined;
parse_query(Sql) ->
case re:run(Sql, "'%[ucCad]'", [global, {capture, all, list}]) of
{match, Variables} ->
Params = [Var || [Var] <- Variables],
Vars = ["$" ++ integer_to_list(I) || I <- lists:seq(1, length(Params))],
NSql = lists:foldl(fun({Param, Var}, S) ->
re:replace(S, Param, Var, [{return, list}])
end, Sql, lists:zip(Params, Vars)),
{NSql, Params};
nomatch ->
{Sql, []}
end.
authorize(Client, PubSub, Topic,
#{annotations := #{id := ResourceID,
query := {Query, Params}
}
}) ->
case emqx_resource:query(ResourceID, {sql, Query, replvar(Params, Client)}) of
{ok, _Columns, []} -> nomatch;
{ok, Columns, Rows} ->
do_authorize(Client, PubSub, Topic, Columns, Rows);
{error, Reason} ->
?LOG(error, "[AuthZ] Query postgresql error: ~p~n", [Reason]),
nomatch
end.
do_authorize(_Client, _PubSub, _Topic, _Columns, []) ->
nomatch;
do_authorize(Client, PubSub, Topic, Columns, [Row | Tail]) ->
case emqx_authz_rule:match(Client, PubSub, Topic,
emqx_authz_rule:compile(format_result(Columns, Row))
) of
{matched, Permission} -> {matched, Permission};
nomatch -> do_authorize(Client, PubSub, Topic, Columns, Tail)
end.
format_result(Columns, Row) ->
Permission = lists:nth(index(<<"permission">>, 2, Columns), erlang:tuple_to_list(Row)),
Action = lists:nth(index(<<"action">>, 2, Columns), erlang:tuple_to_list(Row)),
Topic = lists:nth(index(<<"topic">>, 2, Columns), erlang:tuple_to_list(Row)),
{Permission, all, Action, [Topic]}.
index(Key, N, TupleList) when is_integer(N) ->
Tuple = lists:keyfind(Key, N, TupleList),
index(Tuple, TupleList, 1);
index(_Tuple, [], _Index) -> {error, not_found};
index(Tuple, [Tuple | _TupleList], Index) -> Index;
index(Tuple, [_ | TupleList], Index) -> index(Tuple, TupleList, Index + 1).
replvar(Params, ClientInfo) ->
replvar(Params, ClientInfo, []).
replvar([], _ClientInfo, Acc) ->
lists:reverse(Acc);
replvar(["'%u'" | Params], ClientInfo, Acc) ->
replvar(Params, ClientInfo, [safe_get(username, ClientInfo) | Acc]);
replvar(["'%c'" | Params], ClientInfo = #{clientid := ClientId}, Acc) ->
replvar(Params, ClientInfo, [ClientId | Acc]);
replvar(["'%a'" | Params], ClientInfo = #{peerhost := IpAddr}, Acc) ->
replvar(Params, ClientInfo, [inet_parse:ntoa(IpAddr) | Acc]);
replvar(["'%C'" | Params], ClientInfo, Acc) ->
replvar(Params, ClientInfo, [safe_get(cn, ClientInfo)| Acc]);
replvar(["'%d'" | Params], ClientInfo, Acc) ->
replvar(Params, ClientInfo, [safe_get(dn, ClientInfo)| Acc]);
replvar([Param | Params], ClientInfo, Acc) ->
replvar(Params, ClientInfo, [Param | Acc]).
safe_get(K, ClientInfo) ->
bin(maps:get(K, ClientInfo, "undefined")).
bin(A) when is_atom(A) -> atom_to_binary(A, utf8);
bin(B) when is_binary(B) -> B;
bin(L) when is_list(L) -> list_to_binary(L);
bin(X) -> X.