ó Dª\c@sCdZddlZddlZddlZdd„Zd„ZdS(sm Utility functions for implementing Proof Key for Code Exchange (PKCE) by OAuth Public Clients See RFC7636. iÿÿÿÿNi@cCsbtjtj|ƒƒ}t|ƒdkr9tdƒ‚n%t|ƒdkrZtdƒ‚n|SdS(sŸ Generates a 'code_verifier' as described in section 4.1 of RFC 7636. This is a 'high-entropy cryptographic random string' that will be impractical for an attacker to guess. Args: n_bytes: integer between 31 and 96, inclusive. default: 64 number of bytes of entropy to include in verifier. Returns: Bytestring, representing urlsafe base64-encoded random data. i+s)Verifier too short. n_bytes must be > 30.i€s(Verifier too long. n_bytes must be < 97.N(tbase64turlsafe_b64encodetosturandomtlent ValueError(tn_bytestverifier((sQS:/Maya_2019_DI/build/Release/runTime/plug-ins/MASH/scripts/oauth2client/_pkce.pyt code_verifiers cCstjtj|ƒjƒƒS(sr Creates a 'code_challenge' as described in section 4.2 of RFC 7636 by taking the sha256 hash of the verifier and then urlsafe base64-encoding it. Args: verifier: bytestring, representing a code_verifier as generated by code_verifier(). Returns: Bytestring, representing a urlsafe base64-encoded sha256 hash digest. (RRthashlibtsha256tdigest(R((sQS:/Maya_2019_DI/build/Release/runTime/plug-ins/MASH/scripts/oauth2client/_pkce.pytcode_challenge4s (t__doc__RR RRR (((sQS:/Maya_2019_DI/build/Release/runTime/plug-ins/MASH/scripts/oauth2client/_pkce.pyts