From 652fecd7d037992b89ed1a4eb17f9f467c2aadf7 Mon Sep 17 00:00:00 2001
From: Joseph Sutton <josephsutton@catalyst.net.nz>
Date: Mon, 27 Feb 2023 12:19:08 +1300
Subject: [PATCH 22/34] CVE-2023-0614 s4-dsdb: Add samdb_result_dom_sid_buf()

This function parses a SID from an ldb_message, similar to
samdb_result_dom_sid(), but does it without allocating anything.

BUG: https://bugzilla.samba.org/show_bug.cgi?id=15270

Signed-off-by: Joseph Sutton <josephsutton@catalyst.net.nz>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

Conflict: NA
Reference: https://attachments.samba.org/attachment.cgi?id=17821
---
 source4/dsdb/common/util.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/source4/dsdb/common/util.c b/source4/dsdb/common/util.c
index a30ae662c1e..b556f06cb63 100644
--- a/source4/dsdb/common/util.c
+++ b/source4/dsdb/common/util.c
@@ -365,6 +365,26 @@ struct dom_sid *samdb_result_dom_sid(TALLOC_CTX *mem_ctx, const struct ldb_messa
 	return sid;
 }
 
+/*
+  pull a dom_sid structure from a objectSid in a result set.
+*/
+int samdb_result_dom_sid_buf(const struct ldb_message *msg,
+			     const char *attr,
+			     struct dom_sid *sid)
+{
+	ssize_t ret;
+	const struct ldb_val *v = NULL;
+	v = ldb_msg_find_ldb_val(msg, attr);
+	if (v == NULL) {
+		return LDB_ERR_NO_SUCH_ATTRIBUTE;
+	}
+	ret = sid_parse(v->data, v->length, sid);
+	if (ret == -1) {
+		return LDB_ERR_OPERATIONS_ERROR;
+	}
+	return LDB_SUCCESS;
+}
+
 /*
   pull a guid structure from a objectGUID in a result set.
 */
-- 
2.25.1