private static byte[] CtapCanonicalEncode(CBORObject a, int depth) { CBORObject cbor = a.Untag(); CBORType valueAType = cbor.Type; try { if (valueAType == CBORType.Array) { using (var ms = new MemoryStream()) { CBORObject.WriteValue(ms, 4, cbor.Count); for (var i = 0; i < cbor.Count; ++i) { if (depth >= 3 && IsArrayOrMap(cbor[i])) { throw new CBORException("Nesting level too deep"); } byte[] bytes = CtapCanonicalEncode(cbor[i], depth + 1); ms.Write(bytes, 0, bytes.Length); } return(ms.ToArray()); } } else if (valueAType == CBORType.Map) { KeyValuePair <byte[], byte[]> kv1; List <KeyValuePair <byte[], byte[]> > sortedKeys; sortedKeys = new List <KeyValuePair <byte[], byte[]> >(); foreach (CBORObject key in cbor.Keys) { if (depth >= 3 && (IsArrayOrMap(key) || IsArrayOrMap(cbor[key]))) { throw new CBORException("Nesting level too deep"); } CheckDepth(key, depth + 1); CheckDepth(cbor[key], depth + 1); // Check if key and value can be canonically encoded // (will throw an exception if they cannot) kv1 = new KeyValuePair <byte[], byte[]>( CtapCanonicalEncode(key, depth + 1), CtapCanonicalEncode(cbor[key], depth + 1)); sortedKeys.Add(kv1); } sortedKeys.Sort(ByteComparer); using (var ms = new MemoryStream()) { CBORObject.WriteValue(ms, 5, cbor.Count); byte[] lastKey = null; for (var i = 0; i < sortedKeys.Count; ++i) { kv1 = sortedKeys[i]; byte[] bytes = kv1.Key; if (lastKey != null && ByteArraysEqual(bytes, lastKey)) { throw new CBORException("duplicate canonical CBOR key"); } lastKey = bytes; ms.Write(bytes, 0, bytes.Length); bytes = kv1.Value; ms.Write(bytes, 0, bytes.Length); } return(ms.ToArray()); } } } catch (IOException ex) { throw new InvalidOperationException(ex.ToString(), ex); } if (valueAType == CBORType.SimpleValue || valueAType == CBORType.Boolean || valueAType == CBORType.ByteString || valueAType == CBORType.TextString) { return(cbor.EncodeToBytes(CBOREncodeOptions.Default)); } else if (valueAType == CBORType.FloatingPoint) { long bits = cbor.AsDoubleBits(); return(new byte[] { (byte)0xfb, (byte)((bits >> 56) & 0xffL), (byte)((bits >> 48) & 0xffL), (byte)((bits >> 40) & 0xffL), (byte)((bits >> 32) & 0xffL), (byte)((bits >> 24) & 0xffL), (byte)((bits >> 16) & 0xffL), (byte)((bits >> 8) & 0xffL), (byte)(bits & 0xffL), }); } else if (valueAType == CBORType.Integer) { return(cbor.EncodeToBytes(CBOREncodeOptions.Default)); } else { throw new ArgumentException("Invalid CBOR type."); } }