From: Jeremy Allison <jra@samba.org>
Date: Tue, 24 May 2011 19:47:31 +0000 (-0700)
Subject: Fix our asn.1 parser to handle negative numbers.
X-Git-Url: http://git.samba.org/?a=commitdiff_plain;h=d210395a50b5d5043bdcfb75f670f8abab91f974;p=samba.git

Fix our asn.1 parser to handle negative numbers.

Autobuild-User: Jeremy Allison <jra@samba.org>
Autobuild-Date: Tue May 24 22:57:16 CEST 2011 on sn-devel-104
(cherry picked from commit e719dfd4dc178f001a5f804fb1ac4e587574415f)

Fix bug #8163 (asn.1 library does not correctly read negative integers).
(cherry picked from commit 859d13141cd831488b60e413f7141514ae4464b5)
---

diff --git a/lib/util/asn1.c b/lib/util/asn1.c
index 70c2c57450c..0d696c69978 100644
--- a/lib/util/asn1.c
+++ b/lib/util/asn1.c
@@ -716,10 +716,19 @@ bool asn1_read_ContextSimple(struct asn1_data *data, uint8_t num, DATA_BLOB *blo
 bool asn1_read_implicit_Integer(struct asn1_data *data, int *i)
 {
 	uint8_t b;
+	bool first_byte = true;
 	*i = 0;
 
 	while (!data->has_error && asn1_tag_remaining(data)>0) {
 		if (!asn1_read_uint8(data, &b)) return false;
+		if (first_byte) {
+			if (b & 0x80) {
+				/* Number is negative.
+				   Set i to -1 for sign extend. */
+				*i = -1;
+			}
+			first_byte = false;
+		}
 		*i = (*i << 8) + b;
 	}
 	return !data->has_error;