From: Alan T. DeKok <aland@freeradius.org>
Date: Tue, 13 May 2025 18:26:53 +0000 (-0400)
Subject: allow attribute references as cursors for function arguments
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=fd0be1b2b6e65baa0dcbb480a470a749bcb796f8;p=thirdparty%2Ffreeradius-server.git

allow attribute references as cursors for function arguments

via the somewhat bad hack of adding a flag to xlat_exp_head_t,
because it's too hard to pass in the xlat_arg_parser_t to the
xlat evaluation function
---

diff --git a/src/lib/unlang/xlat_eval.c b/src/lib/unlang/xlat_eval.c
index 74b493a5be9..1d1f83d59db 100644
--- a/src/lib/unlang/xlat_eval.c
+++ b/src/lib/unlang/xlat_eval.c
@@ -489,9 +489,14 @@ check_non_leaf:
 	if (arg->type == FR_TYPE_VOID) return XLAT_ACTION_DONE;
 
 	/*
-	 *	We have a cursor.
+	 *	We already have a pair cursor, the argument was an attribute reference.
 	 */
-	fr_assert(arg->type == FR_TYPE_PAIR_CURSOR);
+	if (vb->type == FR_TYPE_PAIR_CURSOR) return XLAT_ACTION_DONE;
+
+	/*
+	 *	If the argument is a pair
+	 */
+	fr_assert(vb->type != FR_TYPE_PAIR_CURSOR);
 
 	{
 		int err;
@@ -1306,6 +1311,25 @@ xlat_action_t xlat_frame_eval(TALLOC_CTX *ctx, fr_dcursor_t *out, xlat_exp_head_
 
 	if (!*in) return XLAT_ACTION_DONE;
 
+	/*
+	 *	An attribute reference which is a cursor just gets a
+	 *	value-box of cursor returned.  That is filled in
+	 *	later.
+	 */
+	if (unlikely(head && head->cursor)) {
+		int err;
+
+		fr_assert((*in)->type == XLAT_TMPL);
+
+		MEM(value = fr_value_box_alloc(ctx, FR_TYPE_PAIR_CURSOR, NULL));
+
+		(void) tmpl_dcursor_value_box_init(&err, value, request, (*in)->vpt);
+		if (err < -1) return XLAT_ACTION_FAIL;
+
+		fr_dcursor_append(out, value);
+		goto finish;
+	}
+
 	XLAT_DEBUG("** [%i] %s >> entered", unlang_interpret_stack_depth(request), __FUNCTION__);
 
 	for (node = *in; node; node = xlat_exp_next(head, node)) {
diff --git a/src/lib/unlang/xlat_priv.h b/src/lib/unlang/xlat_priv.h
index 982b93e73e5..ff1c3a1973b 100644
--- a/src/lib/unlang/xlat_priv.h
+++ b/src/lib/unlang/xlat_priv.h
@@ -190,6 +190,7 @@ struct xlat_exp_head_s {
 	xlat_flags_t		flags;		//!< Flags that control resolution and evaluation.
 	uint8_t			instantiated : 1;  //!< temporary flag until we fix more things
 	uint8_t			is_argv : 1;	//!< this thing holds function arguments
+	uint8_t			cursor : 1;	//!< otherwise it's too hard to pass xlat_arg_parser_t to the evaluation function.
 
 #ifndef NDEBUG
 	char const * _CONST	file;		//!< File where the xlat was allocated.
diff --git a/src/lib/unlang/xlat_tokenize.c b/src/lib/unlang/xlat_tokenize.c
index 2cdd2d9a47b..405c45ef1ab 100644
--- a/src/lib/unlang/xlat_tokenize.c
+++ b/src/lib/unlang/xlat_tokenize.c
@@ -285,15 +285,11 @@ static int xlat_validate_function_arg(xlat_arg_parser_t const *arg_p, xlat_exp_t
 		}
 
 		/*
-		 *	@todo - in xlat_frame_eval(), push the vpt pointer?  We don't want the _values_ of the
-		 *	referenced attributes, we want a cursor which walks over the referenced attributes.
-		 *
-		 *	Except that the xlat_frame_eval_repeat() doesn't have access to the arg list, so it
-		 *	can't check that we want a tmpl / cursor.  Maybe hack that by restricting the cursor
-		 *	argument to the first one, or the first + variadic of the same type.
+		 *	Bare attribute references are allowed, but are marked up as "return a cursor to this
+		 *	thing, don't return a value".
 		 */
-		fr_strerror_const("Please use strings for references - unquoted strings are not yet supported");
-		return -1;
+		arg->group->cursor = true;
+		return 0;
 	}
 
 	/*
diff --git a/src/tests/keywords/cbor b/src/tests/keywords/cbor
index 9aa14c47bb3..2c7a6628424 100644
--- a/src/tests/keywords/cbor
+++ b/src/tests/keywords/cbor
@@ -34,4 +34,12 @@ if (User-Name != "bob") {
 	test_fail
 }
 
+#
+#  The cursor as an attribute reference, and not as a string.
+#
+cbor := %cbor.encode(User-Name)
+if (cbor != 0x9fa10163626f62ff) {
+	test_fail
+}
+
 success