Authors: Michael DeCandia <firstname.lastname@example.org> and Stephen Becker <email@example.com>
License: BSD License
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HOTP – HMAC-Based One-Time Password Algorithm
* HOTP: Implements RFC 4226 using Ruby. (http://www.ietf.org/rfc/rfc4226.txt) HOTP is an HMAC-SHA1 based algorithm
The latest version of hotp can be found at
Setup based installation is currently unsupported
% gem install hotp
The HOTP object can be used to calculate the HOTP value for any secret and count. The number of digits in the HOTP value is determined by an optional parameter. The default HOTP value is 6 digits long.
Creating an HOTP instance
h = HOTP.new() h.secret=“12345678901234567890” # 20 byte key h.count=0 # Where to start calculating h.digits=6 # How many digits to return (length of the HOTP value) puts(h.hotp) # => “755224” h.count=1 # Change the count puts(h.update) # => “287082”
Using HOTP as a class method
secret = “12345678901234567890” count = 0 puts(HOTP::hotp(secret,count)) # => “755224”