U Zj#@sdZddlmZmZmZmZddlZddlmZm Z m Z ddl m Z m Z ejdkZdZd Zd d Zdd dZddZdddZddZdS)z Functions for parsing and dumping using the ASN.1 DER encoding. Exports the following items: - emit() - parse() - peek() Other type classes are defined that help compose the types listed above. )unicode_literalsdivisionabsolute_importprint_functionN)byte_clschr_cls type_name)int_from_bytes int_to_bytes)zO}||d>O}|dkrld}|dkrZt||d@B|}|sPd}|d?}q,t|dB|}n|t||B7}t|}|dkr|t|7}n$t|}|tdt|B7}||7}|S) a Constructs the header bytes for an ASN.1 object :param class_: An integer ASN.1 class value: 0 (universal), 1 (application), 2 (context), 3 (private) :param method: An integer ASN.1 method value: 0 (primitive), 1 (constructed) :param tag: An integer ASN.1 tag value :param contents: A byte string of the encoded byte contents :return: A byte string of the ASN.1 DER header r'rr,r#r"r%r$r&)rrr ) rrrrheaderZid_numZcont_bitlengthZ length_bytesrrrrs(   r)F)rFr)__doc__ __future__rrrrsys_typesrrr utilr r version_infor/r.r-rr r!rrrrrrs  1 ' j