hci_acl_header
if (nbuf->size < sizeof(struct hci_acl_header)) {
NetBufferHeaderReader<struct hci_acl_header> aclHeader(nbuf);
struct hci_acl_header* headerPkt = (struct hci_acl_header*)data;
NetBufferPrepend<struct hci_acl_header> bufferHeader(curr_frame);
bufferHeader->alen = curr_frame->size - sizeof(struct hci_acl_header);
struct hci_acl_header* header = nb_get_whole_buffer(nbuf);
return header->alen + sizeof(struct hci_acl_header);