U ʹh" @sbdZddlZddlmZddlmZmZmZddlm Z ddd d gZ d dZ d d Z ddd Z dS)a RFC 6979: Deterministic Usage of the Digital Signature Algorithm (DSA) and Elliptic Curve Digital Signature Algorithm (ECDSA) http://tools.ietf.org/html/rfc6979 Many thanks to Coda Hale for his implementation in Go language: https://github.com/codahale/rfc6979 N)hexlify)number_to_stringnumber_to_string_crop bit_length) hmac_compatrbits2int bits2octets generate_kcCs2tt|d}t|d}||kr.|||?S|S)N)intrlen)dataqlenxlr3./venv/lib/python3.8/site-packages/ecdsa/rfc6979.pyrs   cCs,t|t|}||}|dkr"|}t||S)Nr)rrr)rorderZz1Zz2rrrr s cCszt|}|j}|dd}tt||tt||t|f} d|} d|} tj| |d} | | d| D]} | | qn| } t| | |} tj| |d} | | d| D]} | | q| } t| | |} d} t | |krt| | |} | | 7} qt | |}d|kr2|krLnn|dkrD|S|d8}t| | d|} t| | |} qd S) aD Generate the ``k`` value - the nonce for DSA. :param int order: order of the DSA generator used in the signature :param int secexp: secure exponent (private key) in numeric form :param hash_func: reference to the same hash function used for generating hash, like :py:class:`hashlib.sha1` :param bytes data: hash in binary form of the signing data :param int retry_gen: how many good 'k' values to skip before returning :param bytes extra_entropy: additional added data in binary form as per section-3.6 of rfc6979 :rtype: int r )Z digestmodrrrN) rZ digest_sizerrr hmacnewupdateZdigestrr)rZsecexpZ hash_funcrZ retry_genZ extra_entropyrZholenZrolenZbxvkitZsecretrrrr +s@        )rr)__doc__rZbinasciirutilrrrZ_compatr__all__rr r rrrrs