t2otp.exe - Command line TOTP Generator

This tool is created as a command-line emulator of Token2 hardware tokens. It is hardcoded to generate 6 digits, with 30 seconds window, and sha-1 secrets only.

Usage syntax 

t2otp.exe SECRET [skew] [loop]

• the first argument is the value of the secret hash (seed) in base32 format. If the secret value is not supplied, an input box will appear asking to enter the secret value
• the second argument is optional and has to be an integer and defines skew value for time drift (will produce a table with OTPs generated from -SKEW to +SKEW value )
• the third argument is optional if argument equals to 'loop', the tool will stay launched recalculating the current OTP until stopped with Ctrl+C

t2otp.exe -help

• prints help page with usage syntax
  

Example

C:\>t2otp0.2.exe JBSWY3DPEHPK3PXPJBSWY3DPEHPK3PXP 5
Skew       OTP
-5       : 782378
-4       : 596288
-3       : 514279
-2       : 040043
-1       : 603356
 0       : 020836
+1       : 682652
+2       : 546918
+3       : 374175
+4       : 506994
+5       : 699631

---

C:\t2otp0.2.exe -help

 TOKEN2 T2OTP command line TOTP generator v0.2

     for sha1 , 6 digit, 30 seconds OTP generation
     Syntax:

     t2otp.exe SEED [SKEW] [LOOP]

     where:

     SEED  - seed/secret value in base32

     SKEW  - skew value for time drift (will produce a table with OTPs generated from -SKEW to +SKEW value )

     LOOP  - constantly refreshes the OTP table (works  only if SKEW value is provided). 
               OTP regenerates on the 0th and the 30th second

 Examples:

   t2otp.exe JBSWY3DPEHPK3PXPJBSWY3DPEHPK3PXP

                - generates current OTP of the seed

   t2otp.exe JBSWY3DPEHPK3PXPJBSWY3DPEHPK3PXP 4

                - generates 9 OTPs of the seed, starting from -4 and ending with +4 drift (30 seconds each)


   t2otp.exe JBSWY3DPEHPK3PXPJBSWY3DPEHPK3PXP 2 loop

                - constantly generates 5 OTPs of the seed, starting from -2 and ending with +2 drift

                exit by Ctrl+C

   t2otp.exe / t2otp.exe help / t2otp.exe -help

                - prints out this info

                                (C) TOKEN2 Switzerland  https://token2.swiss

Download

The tool can be downloaded here.

Next version

This page describes the previous version of the tool, v1. the new version, v2 is available here