From: Alan T. DeKok <aland@freeradius.org>
Date: Sun, 20 Aug 2023 15:33:40 +0000 (-0400)
Subject: add undocumented immutable xlat, and test based on it
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=33bccaddad944a347743181bccdf6506d83be9e1;p=thirdparty%2Ffreeradius-server.git

add undocumented immutable xlat, and test based on it
---

diff --git a/src/lib/unlang/xlat_builtin.c b/src/lib/unlang/xlat_builtin.c
index b1ee8fb8d95..a4384d46d7c 100644
--- a/src/lib/unlang/xlat_builtin.c
+++ b/src/lib/unlang/xlat_builtin.c
@@ -534,6 +534,64 @@ static xlat_action_t xlat_func_explode(TALLOC_CTX *ctx, fr_dcursor_t *out,
 	return XLAT_ACTION_DONE;
 }
 
+static xlat_arg_parser_t const xlat_func_immutable_attr_args[] = {
+	{ .required = true, .single = true, .type = FR_TYPE_STRING },
+	XLAT_ARG_PARSER_TERMINATOR
+};
+
+/** Mark one or more attributes as immutable
+ *
+ * Example:
+@verbatim
+"%(immutable:&request.State[*])"
+@endverbatim
+ *
+ * @ingroup xlat_functions
+ */
+static xlat_action_t xlat_func_immutable_attr(UNUSED TALLOC_CTX *ctx, UNUSED fr_dcursor_t *out,
+					  UNUSED xlat_ctx_t const *xctx,
+					  request_t *request, fr_value_box_list_t *args)
+{
+	fr_pair_t		*vp;
+	fr_dcursor_t		cursor;
+	tmpl_dcursor_ctx_t	cc;
+	tmpl_t			*vpt;
+	fr_value_box_t		*attr;
+	char const		*fmt;
+
+	XLAT_ARGS(args, &attr);
+
+	fmt = attr->vb_strvalue;
+
+	if (tmpl_afrom_attr_str(request, NULL, &vpt, fmt,
+				&(tmpl_rules_t){
+					.attr = {
+						.dict_def = request->dict,
+						.list_def = request_attr_request,
+						.allow_wildcard = true,
+						.prefix = TMPL_ATTR_REF_PREFIX_AUTO
+					}
+				}) <= 0) {
+		RPEDEBUG("Invalid input");
+		return XLAT_ACTION_FAIL;
+	}
+
+	RIDEBUG("Attributes matching \"%s\"", fmt);
+
+	RINDENT();
+	for (vp = tmpl_dcursor_init(NULL, NULL, &cc, &cursor, request, vpt);
+	     vp;
+	     vp = fr_dcursor_next(&cursor)) {
+		if (fr_type_is_leaf(vp->vp_type)) fr_value_box_set_immutable(&vp->data);
+	}
+	tmpl_dcursor_clear(&cc);
+	REXDENT();
+
+	talloc_free(vpt);
+
+	return XLAT_ACTION_DONE;
+}
+
 static xlat_arg_parser_t const xlat_func_integer_args[] = {
 	{ .required = true, .single = true, .type = FR_TYPE_VOID },
 	XLAT_ARG_PARSER_TERMINATOR
@@ -3328,6 +3386,7 @@ do { \
 
 	XLAT_REGISTER_ARGS("debug", xlat_func_debug, FR_TYPE_INT8, xlat_func_debug_args);
 	XLAT_REGISTER_ARGS("debug_attr", xlat_func_debug_attr, FR_TYPE_NULL, xlat_func_debug_attr_args);
+	XLAT_REGISTER_ARGS("immutable", xlat_func_immutable_attr, FR_TYPE_NULL, xlat_func_immutable_attr_args);
 	XLAT_REGISTER_ARGS("nexttime", xlat_func_next_time, FR_TYPE_UINT64, xlat_func_next_time_args);
 	XLAT_REGISTER_ARGS("pairs", xlat_func_pairs, FR_TYPE_STRING, xlat_func_pairs_args);
 	XLAT_REGISTER_ARGS("subst", xlat_func_subst, FR_TYPE_STRING, xlat_func_subst_args);
diff --git a/src/tests/keywords/immutable b/src/tests/keywords/immutable
new file mode 100644
index 00000000000..8f5af3ca97a
--- /dev/null
+++ b/src/tests/keywords/immutable
@@ -0,0 +1,42 @@
+#
+#  Tests for immutable values.
+#
+#  They can't be modified or deleted.
+#
+&NAS-Port := 1812
+
+#
+#  Editing it is fine.
+#
+&NAS-Port += 1
+if !(&NAS-Port == 1813) {
+	test_fail
+}
+
+#
+#  Mark it as immutable.  The value shouldn't change.
+#
+%(immutable:&request.NAS-Port[*])
+if !(&NAS-Port == 1813) {
+	test_fail
+}
+
+#
+#  Try to edit it.  The value shouldn't change.
+#
+#  @todo - we don't have run-time exceptions... maybe this should return "fail"?
+#
+&NAS-Port += 1
+if !(&NAS-Port == 1813) {
+	test_fail
+}
+
+#
+#  We can't delete it.  Deletion is a noop
+#
+&request -= &NAS-Port[*]
+if !(&NAS-Port == 1813) {
+	test_fail
+}
+
+success