1 files changed, 69 insertions, 0 deletions
diff --git a/crypto/src/asn1/Asn1Utilities.cs b/crypto/src/asn1/Asn1Utilities.cs
index dca2253ec..fe6db2df7 100644
--- a/crypto/src/asn1/Asn1Utilities.cs
+++ b/crypto/src/asn1/Asn1Utilities.cs
@@ -23,5 +23,74 @@ namespace Org.BouncyCastle.Asn1
                 return "[UNIVERSAL " + tagNo + "]";
             }
         }
+
+        /*
+         * Wrappers for Asn1TaggedObject.GetExplicitBaseObject
+         */
+
+        public static Asn1Encodable GetExplicitBaseObject(Asn1TaggedObject taggedObject, int tagClass, int tagNo)
+        {
+            if (!taggedObject.HasTag(tagClass, tagNo))
+            {
+                string expected = GetTagText(tagClass, tagNo);
+                string found = GetTagText(taggedObject);
+                throw new InvalidOperationException("Expected " + expected + " tag but found " + found);
+            }
+
+            return taggedObject.GetExplicitBaseObject();
+        }
+
+        public static Asn1Encodable GetExplicitContextBaseObject(Asn1TaggedObject taggedObject, int tagNo)
+        {
+            return GetExplicitBaseObject(taggedObject, Asn1Tags.ContextSpecific, tagNo);
+        }
+
+        public static Asn1Encodable TryGetExplicitBaseObject(Asn1TaggedObject taggedObject, int tagClass, int tagNo)
+        {
+            if (!taggedObject.HasTag(tagClass, tagNo))
+                return null;
+
+            return taggedObject.GetExplicitBaseObject();
+        }
+
+        public static Asn1Encodable TryGetExplicitContextBaseObject(Asn1TaggedObject taggedObject, int tagNo)
+        {
+            return TryGetExplicitBaseObject(taggedObject, Asn1Tags.ContextSpecific, tagNo);
+        }
+
+
+        /*
+         * Wrappers for Asn1TaggedObject.GetExplicitBaseTagged
+         */
+
+        public static Asn1TaggedObject GetExplicitBaseTagged(Asn1TaggedObject taggedObject, int tagClass, int tagNo)
+        {
+            if (!taggedObject.HasTag(tagClass, tagNo))
+            {
+                string expected = GetTagText(tagClass, tagNo);
+                string found = GetTagText(taggedObject);
+                throw new InvalidOperationException("Expected " + expected + " tag but found " + found);
+            }
+
+            return taggedObject.GetExplicitBaseTagged();
+        }
+
+        public static Asn1TaggedObject GetExplicitContextBaseTagged(Asn1TaggedObject taggedObject, int tagNo)
+        {
+            return GetExplicitBaseTagged(taggedObject, Asn1Tags.ContextSpecific, tagNo);
+        }
+
+        public static Asn1TaggedObject TryGetExplicitBaseTagged(Asn1TaggedObject taggedObject, int tagClass, int tagNo)
+        {
+            if (!taggedObject.HasTag(tagClass, tagNo))
+                return null;
+
+            return taggedObject.GetExplicitBaseTagged();
+        }
+
+        public static Asn1TaggedObject TryGetExplicitContextBaseTagged(Asn1TaggedObject taggedObject, int tagNo)
+        {
+            return TryGetExplicitBaseTagged(taggedObject, Asn1Tags.ContextSpecific, tagNo);
+        }
     }
 }