lib/otp/utils.rb in otp-0.0.9 vs lib/otp/utils.rb in otp-0.0.10
- old
+ new
@@ -2,23 +2,36 @@
module OTP
module Utils
private
+ def otp(algorithm, secret, moving_factor, digits)
+ message = pack_int64(moving_factor)
+ digest = hmac(algorithm, secret, message)
+ num = pickup(digest)
+ return truncate(num, digits)
+ end
+
def pack_int64(i)
return [i >> 32 & 0xffffffff, i & 0xffffffff].pack("NN")
end
def hmac(algorithm, secret, text)
mac = OpenSSL::HMAC.new(secret, algorithm)
mac << text
return mac.digest
end
- def truncate(hash)
- offset = hash[-1].ord & 0xf
- binary = hash[offset, 4]
+ def pickup(digest)
+ offset = digest[-1].ord & 0xf
+ binary = digest[offset, 4]
return binary.unpack("N")[0] & 0x7fffffff
+ end
+
+ def truncate(num, digits)
+ pw = (num % (10 ** digits)).to_s
+ pw.prepend("0") while pw.length < digits
+ return pw
end
def compare(a, b)
return a.to_i == b.to_i
end