From 3329d1f805377e582df54094b98967c51494378e Mon Sep 17 00:00:00 2001
From: Paul Bakker <p.j.bakker@polarssl.org>
Date: Wed, 12 Oct 2011 09:55:01 +0000
Subject: [PATCH]  - Fixed a bug where the CRL parser expected an EXPLICIT
 ASN.1 tag before version numbers

---
 ChangeLog           |  2 ++
 library/x509parse.c | 22 +++++++++++++++++++++-
 2 files changed, 23 insertions(+), 1 deletion(-)

diff --git a/ChangeLog b/ChangeLog
index bf33cf7d4..000f7cd25 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -18,6 +18,8 @@ Changes
 Bugfix
    * Fixed faulty HMAC-MD2 implementation. Found by dibac. (Closes
      ticket #37)
+   * Fixed a bug where the CRL parser expected an EXPLICIT ASN.1 tag
+     before version numbers
 
 = Version 1.0.0 released on 2011-07-27
 Features
diff --git a/library/x509parse.c b/library/x509parse.c
index e359ca7ac..bdafb22ea 100644
--- a/library/x509parse.c
+++ b/library/x509parse.c
@@ -306,6 +306,26 @@ static int x509_get_version( unsigned char **p,
     return( 0 );
 }
 
+/*
+ *  Version  ::=  INTEGER  {  v1(0), v2(1), v3(2)  }
+ */
+static int x509_crl_get_version( unsigned char **p,
+                             const unsigned char *end,
+                             int *ver )
+{
+    int ret;
+
+    if( ( ret = asn1_get_int( p, end, ver ) ) != 0 )
+    {
+        if( ret == POLARSSL_ERR_ASN1_UNEXPECTED_TAG )
+            return( *ver = 0 );
+
+        return( POLARSSL_ERR_X509_CERT_INVALID_VERSION + ret );
+    }
+
+    return( 0 );
+}
+
 /*
  *  CertificateSerialNumber  ::=  INTEGER
  */
@@ -1613,7 +1633,7 @@ int x509parse_crl( x509_crl *chain, const unsigned char *buf, size_t buflen )
      *
      * signature            AlgorithmIdentifier
      */
-    if( ( ret = x509_get_version( &p, end, &crl->version ) ) != 0 ||
+    if( ( ret = x509_crl_get_version( &p, end, &crl->version ) ) != 0 ||
         ( ret = x509_get_alg(  &p, end, &crl->sig_oid1   ) ) != 0 )
     {
         x509_crl_free( crl );