+ THiz"Rt^RIHt^RIHt^RIHtRR.tRtRt Rt Rt ^t RRlt RsRsRR ltR tR tR tR t]!]]]R 7tRRlt]!R4RtR#)z'scrypt hash frontend and help utilities)warn)exc)to_bytesvalidatescryptcV^8d\RV: 24hV^8d\RV: 24hW,\8d\RV: RV: 24hV^8gW^, ,'d\RV: 24hR#)a- helper which validates a set of scrypt config parameters. scrypt will take ``O(n * r * p)`` time and ``O(n * r)`` memory. limitations are that ``n = 2**``, ``n < 2**(16*r)``, ``r * p < 2 ** 30``. :param n: scrypt rounds :param r: scrypt block size :param p: scrypt parallel factor zr must be > 0: r=zp must be > 0: p=zr * p must be < 2**30: r=z, p=z#n must be > 1, and a power of 2: n=T) ValueErrorMAX_RP)nrps&&&@/usr/lib/python3/dist-packages/passlib/crypto/scrypt/__init__.pyrrs 1u,QE2331u,QE233uv~4QEaUCDD1uU >qeDEE cV^V,^ V^,,\,,,p\WC,4#)a# calculate memory required for parameter combination. assumes parameters have already been validated. .. warning:: this is derived from OpenSSL's scrypt maxmem formula; and may not be correct for other implementations (additional buffers, different parallelism tradeoffs, etc). ) UINT32_SIZEint)r r r fudgemaxmems&&&& r estimate_maxmemr<s1"#'B!a%L;66 7F v~ rNc\W#V4\VRR7p\VRR7pV^8d \R4hV\8d\R\,4h\ WW#WE4#)arun SCrypt key derivation function using specified parameters. :arg secret: passphrase string (str is encoded to bytes using utf-8). :arg salt: salt string (str is encoded to bytes using utf-8). :arg n: integer 'N' parameter :arg r: integer 'r' parameter :arg p: integer 'p' parameter :arg keylen: number of bytes of key to generate. defaults to 32 (the internal block size). :returns: a *keylen*-sized bytes instance SCrypt imposes a number of constraints on it's input parameters: * ``r * p < 2**30`` -- due to a limitation of PBKDF2-HMAC-SHA256. * ``keylen < (2**32 - 1) * 32`` -- due to a limitation of PBKDF2-HMAC-SHA256. * ``n`` must a be a power of 2, and > 1 -- internal limitation of scrypt() implementation :raises ValueError: if the provided parameters are invalid (see constraints above). .. warning:: Unless the third-party ``scrypt ``_ package is installed, passlib will use a builtin pure-python implementation of scrypt, which is *considerably* slower (and thus requires a much lower / less secure ``n`` value in order to be usuable). Installing the :mod:`!scrypt` package is strongly recommended. secret)paramsaltzkeylen must be at least 1zkeylen too large, must be <= %d)rrr MAX_KEYLEN_scrypt)rrr r r keylens&&&&&&r rr\sbR Q1 fH -F D 'D z455 :ZGHH 6q 11rcl^dp\RV,\P4^RIHpVP #)z< Load pure-python scrypt implementation built into passlib. zUsing builtin scrypt backend, which is %dx slower than is required for adequate security. Installing scrypt support (via 'pip install scrypt') is strongly recommended) ScryptEngine)rrPasslibSecurityWarning_builtinrexecute)slowdownrs r _load_builtin_backendr"s:H "$, - ""  '   rc^RIHpV# \dMi;i^RIp\R\P 4R# \d6pR\ T49d\R\P 4Rp?R#Rp?ii;i)z Try to import the ctypes-based scrypt hash function provided by the ``scrypt ``_ package. )hashNz5'scrypt' package is too old (lacks ``hash()`` method)rzJ'scrypt' package failed to import correctly (possible installation issue?))rr$ ImportErrorrrPasslibWarningstr)r$rerrs r _load_cffi_backendr)s}        CSEWEW    3s8 # \""  s! < A<*A77A<cFa^RIHoT3RlpT# \dR#i;i)zZ Attempt to load stdlib scrypt() implement and return wrapper. Returns None if not found. )rNc N<\pV^8d \W#V4pS!WW#WEVR7#))passwordrr r r dklenr) SCRYPT_MAXMEMr)rrr r r rr stdlib_scrypts&&&&&& r stdlib_scrypt_wrapper3_load_stdlib_backend..stdlib_scrypt_wrappers3 A:$Q1-F!AF  r)hashlibrr%)r1r0s @r _load_stdlib_backendr4s, 3 & ! - s   )stdlibrbuiltincVR8XdR#VR8Xd2\Fp\WR7R# \P!R4h\P V4pV'g\ RV: 24hV!4pV'g\P!RV: R24hV'dR#VsVsR# \PdKi;i) z set backend for scrypt(). if name not specified, loads first available. :raises ~passlib.exc.MissingBackendError: if backend can't be found .. note:: mainly intended to be called by unittests, and scrypt hash handler anyNdefaultdryrunzno scrypt backends availablezunknown scrypt backend: zscrypt backend z not available) backend_values _set_backendrMissingBackendError_backend_loadersgetrbackendr)namer;loaderr$s&& r r=r=s u} y"D T1# %%&DEE  ! !$ 'F 3D8<== 8D %%x~&NOO GG**  s B((CCr9cZ\VRR7R# \PdR#i;i)Tr:F)r=rr>)rBs&r _has_backendrE s,T$'  " "s **li?)g?) )F)__doc__warningsrpasslibr passlib.utilsr__all__r/rr rrrrrArr"r)r4r<dictr?r=rErr rPs-"   "  8 4  02f  <!D1   !@ Yr