auth: Accept forward_fields from auth client

src/auth/auth-request.c

@@ -407,6 +407,9 @@ bool auth_request_import_info(struct auth_request *request,
 		request->debug = TRUE;
 	else if (strcmp(key, "client_id") == 0)
 		request->client_id = p_strdup(request->pool, value);
+	else if (strcmp(key, "forward_fields") == 0)
+		auth_fields_import_prefixed(request->extra_fields,
+					    "forward_", value, 0);
 	else
 		return FALSE;
 	/* NOTE: keep in sync with auth_request_export() */

src/lib-auth/auth-client-request.c

@@ -90,6 +90,11 @@ static void auth_server_send_new_request(struct auth_server_connection *conn,
 		str_append(str, "\tclient_id=");
 		str_append_tabescaped(str, info->client_id);
 	}
+	if (info->forward_fields != NULL &&
+	    *info->forward_fields != '\0') {
+		str_append(str, "\tforward_fields=");
+		str_append_tabescaped(str, info->forward_fields);
+	}
 	if (info->initial_resp_base64 != NULL) {
 		str_append(str, "\tresp=");
 		str_append_tabescaped(str, info->initial_resp_base64);

src/lib-auth/auth-client.h

@@ -43,6 +43,7 @@ struct auth_request_info {
 	const char *cert_username;
 	const char *local_name;
 	const char *client_id;
+	const char *forward_fields;
 	enum auth_request_flags flags;
 
 	struct ip_addr local_ip, remote_ip, real_local_ip, real_remote_ip;

src/login-common/client-common.h

@@ -144,6 +144,7 @@ struct client {
 	const char *session_id, *listener_name, *postlogin_socket_path;
 	const char *local_name;
 	string_t *client_id;
+	string_t *forward_fields;
 
 	int fd;
 	struct istream *input;

src/login-common/sasl-server.c

@@ -369,6 +369,8 @@ void sasl_server_auth_begin(struct client *client,
 	info.real_remote_port = client->real_remote_port;
 	if (client->client_id != NULL)
 		info.client_id = str_c(client->client_id);
+	if (client->forward_fields != NULL)
+		info.forward_fields = str_c(client->forward_fields);
 	info.initial_resp_base64 = initial_resp_base64;
 
 	client->auth_request =