Please refer to the package description for an overview of OTP.
If you need to generate HOTP password described in RFC4226, then use
>>> hotp SHA1 "1234" 100 6
317569
>>> hotp SHA512 "1234" 100 6
134131Or
>>> totp SHA1 "1234" (read "2010-10-10 00:01:00 UTC") 30 8
43388892to generate TOTP password described in RFC6238.
hotpCheck :: HashAlgorithm -- ^ Hashing algorithm
-> Secret -- ^ Shared secret
-> (Word8, Word8) -- ^ how much counters to take lower and higher than ideal
-> Word64 -- ^ ideal (expected) counter value
-> Word8 -- ^ Number of digits in password
-> Word32 -- ^ Password entered by user
-> Bool -- ^ True if password acceptable>>> hotpCheck SHA1 "1234" (0,0) 10 6 50897
True
>>> hotpCheck SHA1 "1234" (0,0) 9 6 50897
False
>>> hotpCheck SHA1 "1234" (0,1) 9 6 50897
TrueHere almost the same aguments as for hotp function, but there is
also (0, 0) tuple. This tuple describes range of counters to check
in case of desynchronisation of counters between client and
server. I.e. if you specify (1, 1) and ideal counter will be 10
then function will check passwords for [9, 10, 11] list of
counters.
Here is the same for TOTP:
>>> totpCheck SHA1 "1234" (0, 0) (read "2010-10-10 00:00:00 UTC") 30 6 778374
True
>>> totpCheck SHA1 "1234" (0, 0) (read "2010-10-10 00:00:30 UTC") 30 6 778374
False
>>> totpCheck SHA1 "1234" (1, 0) (read "2010-10-10 00:00:30 UTC") 30 6 778374
True