From: martijn <martijn@openbsd.org>
Date: Fri, 10 Nov 2023 12:12:02 +0000 (+0000)
Subject: Give ober_printf_elements() a ber_element array, similar to
X-Git-Url: http://artulab.com/gitweb/?a=commitdiff_plain;h=40632feda6a4f5d674c1e0d0ee088fd00fbf89b5;p=openbsd

Give ober_printf_elements() a ber_element array, similar to
ober_scanf_elements(). This allows us to move down and back up multiple
levels in with nested sequences and sets.

While here, on failure, make sure we free (and unlink if needed) all
elements we created.

OK claudio@, tb@
---

diff --git a/lib/libutil/ber.c b/lib/libutil/ber.c
index cd3bcd0623a..c21f2d8daf8 100644
--- a/lib/libutil/ber.c
+++ b/lib/libutil/ber.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: ber.c,v 1.25 2023/08/22 12:50:27 gerhard Exp $ */
+/*	$OpenBSD: ber.c,v 1.26 2023/11/10 12:12:02 martijn Exp $ */
 
 /*
  * Copyright (c) 2007, 2012 Reyk Floeter <reyk@openbsd.org>
@@ -576,20 +576,25 @@ ober_get_oid(struct ber_element *elm, struct ber_oid *o)
 	return (0);
 }
 
+#define _MAX_SEQ		 128
 struct ber_element *
 ober_printf_elements(struct ber_element *ber, char *fmt, ...)
 {
 	va_list			 ap;
-	int			 d, class;
+	int			 d, class, level = 0;
 	size_t			 len;
 	unsigned int		 type;
 	long long		 i;
 	char			*s;
 	void			*p;
 	struct ber_oid		*o;
-	struct ber_element	*sub = ber, *e;
+	struct ber_element	*parent[_MAX_SEQ], *e;
+	struct ber_element	*origber = ber, *firstber = NULL;
+
+	memset(parent, 0, sizeof(struct ber_element *) * _MAX_SEQ);
 
 	va_start(ap, fmt);
+	
 	while (*fmt) {
 		switch (*fmt++) {
 		case 'B':
@@ -653,16 +658,24 @@ ober_printf_elements(struct ber_element *ber, char *fmt, ...)
 				goto fail;
 			break;
 		case '{':
-			if ((ber = sub = ober_add_sequence(ber)) == NULL)
+			if (level >= _MAX_SEQ-1)
+				goto fail;
+			if ((ber= ober_add_sequence(ber)) == NULL)
 				goto fail;
+			parent[level++] = ber;
 			break;
 		case '(':
-			if ((ber = sub = ober_add_set(ber)) == NULL)
+			if (level >= _MAX_SEQ-1)
+				goto fail;
+			if ((ber = ober_add_set(ber)) == NULL)
 				goto fail;
+			parent[level++] = ber;
 			break;
 		case '}':
 		case ')':
-			ber = sub;
+			if (level <= 0 || parent[level - 1] == NULL)
+				goto fail;
+			ber = parent[--level];
 			break;
 		case '.':
 			if ((e = ober_add_eoc(ber)) == NULL)
@@ -672,19 +685,22 @@ ober_printf_elements(struct ber_element *ber, char *fmt, ...)
 		default:
 			break;
 		}
+		if (firstber == NULL)
+			firstber = ber;
 	}
 	va_end(ap);
 
 	return (ber);
  fail:
-	ober_free_elements(ber);
+	if (origber != NULL)
+		ober_unlink_elements(origber);
+	ober_free_elements(firstber);
 	return (NULL);
 }
 
 int
 ober_scanf_elements(struct ber_element *ber, char *fmt, ...)
 {
-#define _MAX_SEQ		 128
 	va_list			 ap;
 	int			*d, level = -1;
 	unsigned int		*t;