parse static method

ASN1OctetString parse(
  1. MutableIterable bytes
)
override

Implementation

static ASN1OctetString parse(final MutableIterable bytes) {
  if (bytes.length < 2) {
    throw Exception('Invalid data!');
  }

  int tag = bytes.first;
  if (tag != ASN1Type.octetStringTag) {
    throw Exception('Invalid tag!');
  }
  bytes.mutate = bytes.skip(1);

  final lengthBigInt = ASN1Object.decodeLength(bytes);
  int length = lengthBigInt.toInt();
  if (length == 0) {
    return ASN1OctetString(Uint8List(0));
  }

  if (bytes.length < length) {
    throw Exception('Invalid data');
  }

  final contentBytes = bytes.take(length);
  bytes.mutate = bytes.skip(length);

  return ASN1OctetString(Uint8List.fromList(contentBytes.toList()));
}