if cs == nil {
		return nil
	}
	r.contentHash = *cs
	if ignoreValue {
		// Do not validate, but allow for transfer
		return nil
	}

	r.contentHasher = cs.Type.Hasher()
	if r.contentHasher == nil {
		return ErrInvalidChecksum
	}
	return nil
}

func (r *Reader) Read(p []byte) (int, error) {
	n, err := r.src.Read(p)
	r.bytesRead += int64(n)
	if r.sha256 != nil {