feat: support initialize client attribute from user property

apps/emqx/src/emqx_channel.erl

@@ -263,7 +263,8 @@ init(
         },
         Zone
     ),
-    ClientInfo = initialize_client_attrs_from_cert(ClientInfo0, Peercert, Zone),
+    AttrExtractionConfig = get_mqtt_conf(Zone, client_attrs_init),
+    ClientInfo = initialize_client_attrs_from_cert(AttrExtractionConfig, ClientInfo0, Peercert),
     {NClientInfo, NConnInfo} = take_ws_cookie(ClientInfo, ConnInfo),
     #channel{
         conninfo = NConnInfo,
@@ -1576,30 +1577,31 @@ enrich_client(ConnPkt, Channel = #channel{clientinfo = ClientInfo}) ->
             {error, ReasonCode, Channel#channel{clientinfo = NClientInfo}}
     end.
 
-initialize_client_attrs_from_cert(ClientInfo, Peercert, Zone) ->
+initialize_client_attrs_from_cert(
-    case get_mqtt_conf(Zone, client_attrs_init) of
+    #{
-        #{
+        extract_from := From,
-            extract_from := From,
+        extract_regexp := Regexp,
-            extract_regexp := Regexp,
+        extract_as := AttrName
-            extract_as := AttrName
+    },
-        } when From =:= cn orelse From =:= dn ->
+    ClientInfo,
-            case extract_client_attr_from_cert(From, Regexp, Peercert) of
+    Peercert
-                {ok, Value} ->
+) when From =:= cn orelse From =:= dn ->
-                    ?SLOG(
+    case extract_client_attr_from_cert(From, Regexp, Peercert) of
-                        debug,
+        {ok, Value} ->
-                        #{
+            ?SLOG(
-                            msg => "client_attr_init_from_cert",
+                debug,
-                            extracted_as => AttrName,
+                #{
-                            extracted_value => Value
+                    msg => "client_attr_init_from_cert",
-                        }
+                    extracted_as => AttrName,
-                    ),
+                    extracted_value => Value
-                    ClientInfo#{client_attrs => #{AttrName => Value}};
+                }
-                _ ->
+            ),
-                    ClientInfo#{client_attrs => #{}}
+            ClientInfo#{client_attrs => #{AttrName => Value}};
-            end;
         _ ->
             ClientInfo#{client_attrs => #{}}
-    end.
+    end;
+initialize_client_attrs_from_cert(_, ClientInfo, _Peercert) ->
+    ClientInfo.
 
 extract_client_attr_from_cert(cn, Regexp, Peercert) ->
     CN = esockd_peercert:common_name(Peercert),
@@ -1656,9 +1658,10 @@ maybe_assign_clientid(#mqtt_packet_connect{clientid = <<>>}, ClientInfo) ->
 maybe_assign_clientid(#mqtt_packet_connect{clientid = ClientId}, ClientInfo) ->
     {ok, ClientInfo#{clientid => ClientId}}.
 
-maybe_set_client_initial_attr(_, #{zone := Zone} = ClientInfo) ->
+maybe_set_client_initial_attr(ConnPkt, #{zone := Zone} = ClientInfo0) ->
-    Attrs = maps:get(client_attrs, ClientInfo, #{}),
     Config = get_mqtt_conf(Zone, client_attrs_init),
+    ClientInfo = initialize_client_attrs_from_user_property(Config, ConnPkt, ClientInfo0),
+    Attrs = maps:get(client_attrs, ClientInfo, #{}),
     case extract_attr_from_clientinfo(Config, ClientInfo) of
         {ok, Value} ->
             #{extract_as := Name} = Config,
@@ -1675,6 +1678,43 @@ maybe_set_client_initial_attr(_, #{zone := Zone} = ClientInfo) ->
             {ok, ClientInfo}
     end.
 
+initialize_client_attrs_from_user_property(
+    #{
+        extract_from := user_property,
+        extract_as := PropertyKey
+    },
+    ConnPkt,
+    ClientInfo
+) ->
+    case extract_client_attr_from_user_property(ConnPkt, PropertyKey) of
+        {ok, Value} ->
+            ?SLOG(
+                debug,
+                #{
+                    msg => "client_attr_init_from_user_property",
+                    extracted_as => PropertyKey,
+                    extracted_value => Value
+                }
+            ),
+            ClientInfo#{client_attrs => #{PropertyKey => Value}};
+        _ ->
+            ClientInfo
+    end;
+initialize_client_attrs_from_user_property(_, _ConnInfo, ClientInfo) ->
+    ClientInfo.
+
+extract_client_attr_from_user_property(
+    #mqtt_packet_connect{properties = #{'User-Property' := UserProperty}}, PropertyKey
+) ->
+    case lists:keyfind(PropertyKey, 1, UserProperty) of
+        {_, Value} ->
+            {ok, Value};
+        _ ->
+            not_found
+    end;
+extract_client_attr_from_user_property(_ConnPkt, _PropertyKey) ->
+    ignored.
+
 extract_attr_from_clientinfo(#{extract_from := clientid, extract_regexp := Regexp}, #{
     clientid := ClientId
 }) ->

apps/emqx/src/emqx_schema.erl

@@ -1736,8 +1736,8 @@ fields("client_attrs_init") ->
     [
         {extract_from,
             sc(
-                hoconsc:enum([clientid, username, cn, dn]),
+                hoconsc:enum([clientid, username, cn, dn, user_property]),
-                #{desc => ?DESC("client_atrs_init_extract_from")}
+                #{desc => ?DESC("client_attrs_init_extract_from")}
             )},
         {extract_regexp, sc(binary(), #{desc => ?DESC("client_attrs_init_extract_regexp")})},
         {extract_as,
@@ -2010,6 +2010,8 @@ desc("session_persistence") ->
     "Settings governing durable sessions persistence.";
 desc(durable_storage) ->
     ?DESC(durable_storage);
+desc("client_attrs_init") ->
+    ?DESC(client_attrs_init);
 desc(_) ->
     undefined.
 

apps/emqx/test/emqx_client_SUITE.erl

@@ -77,6 +77,7 @@ groups() ->
             t_username_as_clientid,
             t_certcn_as_alias,
             t_certdn_as_alias,
+            t_client_attr_from_user_property,
             t_certcn_as_clientid_default_config_tls,
             t_certcn_as_clientid_tlsv1_3,
             t_certcn_as_clientid_tlsv1_2,
@@ -408,10 +409,33 @@ test_cert_extraction_as_alias(Which) ->
     {ok, _} = emqtt:connect(Client),
     %% assert only two chars are extracted
     ?assertMatch(
-        #{clientinfo := #{client_attrs := #{alias := <<_, _>>}}}, emqx_cm:get_chan_info(ClientId)
+        #{clientinfo := #{client_attrs := #{<<"alias">> := <<_, _>>}}},
+        emqx_cm:get_chan_info(ClientId)
     ),
     emqtt:disconnect(Client).
 
+t_client_attr_from_user_property(_Config) ->
+    ClientId = atom_to_binary(?FUNCTION_NAME),
+    emqx_config:put_zone_conf(default, [mqtt, client_attrs_init], #{
+        extract_from => user_property,
+        extract_as => <<"group">>
+    }),
+    SslConf = emqx_common_test_helpers:client_mtls('tlsv1.3'),
+    {ok, Client} = emqtt:start_link([
+        {clientid, ClientId},
+        {port, 8883},
+        {ssl, true},
+        {ssl_opts, SslConf},
+        {proto_ver, v5},
+        {properties, #{'User-Property' => [{<<"group">>, <<"g1">>}]}}
+    ]),
+    {ok, _} = emqtt:connect(Client),
+    %% assert only two chars are extracted
+    ?assertMatch(
+        #{clientinfo := #{client_attrs := #{<<"group">> := <<"g1">>}}},
+        emqx_cm:get_chan_info(ClientId)
+    ),
+    emqtt:disconnect(Client).
 t_certcn_as_clientid_default_config_tls(_) ->
     tls_certcn_as_clientid(default).
 

rel/i18n/emqx_schema.hocon

@@ -1592,12 +1592,14 @@ client_attrs_init_extract_from {
     - `username`: Extract from the username.
     - `cn`: Extract from the Common Name (CN) field of the client certificate.
     - `dn`: Extract from the Distinguished Name (DN) field of the client certficate.
+    - `user_property`: Extract from the user property sent in the MQTT v5 `CONNECT` packet.
+      In this case, `extract_regex` is not applicable, and `extract_as` should be the user property key.
 
     NOTE: this extraction happens **after** `clientid` or `username` is initialized
     from `peer_cert_as_clientid` or `peer_cert_as_username` config."""
 }
 
-client_attrs_init_extract_regex {
+client_attrs_init_extract_regexp {
   label: "Client attribute extract regex"
   desc: """~
     The regular expression to extract a client attribute from the client property specified by `client_attrs_init.extract_from` config.
@@ -1610,7 +1612,8 @@ client_attrs_init_extract_as {
   label: "Name the extracted attribute"
   desc: """~
     The name of the client attribute extracted from the client property specified by `client_attrs_init.extract_from` config.
-    The extracted attribute will be stored in the `client_attr` property with this name."""
+    The extracted attribute will be stored in the `client_attr` property with this name.
+    In case `extract_from = user_property`, this should be the key of the user property."""
 }
 
 }