asn1_der_decoding2: force the right tag on DER
When decoding an OCTET STRING ensure that the right
tag is present when strict DER is specified.
Signed-off-by: Nikos Mavrogiannopoulos <nmav@gnutls.org>
diff --git a/lib/decoding.c b/lib/decoding.c
index 8366d48..6cc6a3f 100644
--- a/lib/decoding.c
+++ b/lib/decoding.c
@@ -1179,6 +1179,13 @@
ptag = der + counter - inner_tag_len;
if ((flags & ASN1_DECODE_FLAG_STRICT_DER) || !(ptag[0] & ASN1_CLASS_STRUCTURED))
{
+ if (ptag[0] & ASN1_CLASS_STRUCTURED)
+ {
+ result = ASN1_DER_ERROR;
+ warn();
+ goto cleanup;
+ }
+
len2 =
asn1_get_length_der (der + counter, ider_len, &len3);
if (len2 < 0)
