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 70c2c57450cc1de869fab961de8ea55911e8c9e4..0d696c699781db5bf5baab87560639b6ef7151b9 100644 (file)
--- 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;