(Excel) TOTP Algorithm: Time-Based One-Time Password Algorithm

Demonstrates how to generate an time-based one-time password (TOTP) as specified in RFC 6238. This is the algorithm used by Google Authenticator.

Note: This example requires Chilkat v9.5.0.77 or greater.

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' This example requires the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

Dim crypt As Chilkat.Crypt2
Set crypt = Chilkat.NewCrypt2

' Duplicate the following results from RFC 6238

' TOTP Algorithm: Test Values
' 
' +-------------+--------------+------------------+----------+--------+
' |  Time (sec) |   UTC Time   | Value of T (hex) |   TOTP   |  Mode  |
' +-------------+--------------+------------------+----------+--------+
' |      59     |  1970-01-01  | 0000000000000001 | 94287082 |  SHA1  |
' |             |   00:00:59   |                  |          |        |
' |      59     |  1970-01-01  | 0000000000000001 | 46119246 | SHA256 |
' |             |   00:00:59   |                  |          |        |
' |      59     |  1970-01-01  | 0000000000000001 | 90693936 | SHA512 |
' |             |   00:00:59   |                  |          |        |
' |  1111111109 |  2005-03-18  | 00000000023523EC | 07081804 |  SHA1  |
' |             |   01:58:29   |                  |          |        |
' |  1111111109 |  2005-03-18  | 00000000023523EC | 68084774 | SHA256 |
' |             |   01:58:29   |                  |          |        |
' |  1111111109 |  2005-03-18  | 00000000023523EC | 25091201 | SHA512 |
' |             |   01:58:29   |                  |          |        |
' |  1111111111 |  2005-03-18  | 00000000023523ED | 14050471 |  SHA1  |
' |             |   01:58:31   |                  |          |        |
' |  1111111111 |  2005-03-18  | 00000000023523ED | 67062674 | SHA256 |
' |             |   01:58:31   |                  |          |        |
' |  1111111111 |  2005-03-18  | 00000000023523ED | 99943326 | SHA512 |
' |             |   01:58:31   |                  |          |        |
' |  1234567890 |  2009-02-13  | 000000000273EF07 | 89005924 |  SHA1  |
' |             |   23:31:30   |                  |          |        |
' |  1234567890 |  2009-02-13  | 000000000273EF07 | 91819424 | SHA256 |
' |             |   23:31:30   |                  |          |        |
' |  1234567890 |  2009-02-13  | 000000000273EF07 | 93441116 | SHA512 |
' |             |   23:31:30   |                  |          |        |
' |  2000000000 |  2033-05-18  | 0000000003F940AA | 69279037 |  SHA1  |
' |             |   03:33:20   |                  |          |        |
' |  2000000000 |  2033-05-18  | 0000000003F940AA | 90698825 | SHA256 |
' |             |   03:33:20   |                  |          |        |
' |  2000000000 |  2033-05-18  | 0000000003F940AA | 38618901 | SHA512 |
' |             |   03:33:20   |                  |          |        |
' | 20000000000 |  2603-10-11  | 0000000027BC86AA | 65353130 |  SHA1  |
' |             |   11:33:20   |                  |          |        |
' | 20000000000 |  2603-10-11  | 0000000027BC86AA | 77737706 | SHA256 |
' |             |   11:33:20   |                  |          |        |
' | 20000000000 |  2603-10-11  | 0000000027BC86AA | 47863826 | SHA512 |
' |             |   11:33:20   |                  |          |        |
' +-------------+--------------+------------------+----------+--------+

' Seed for HMAC-SHA1

seed = "3132333435363738393031323334353637383930"

' Seed for HMAC-SHA256 - 32 bytes

seed32 = "3132333435363738393031323334353637383930313233343536373839303132"

' Seed for HMAC-SHA512 - 64 bytes

seed64 = "31323334353637383930313233343536373839303132333435363738393031323334353637383930313233343536373839303132333435363738393031323334"

' See the online reference documentation for an explanation of arguments.
Debug.Print "TOTP(59,sha1) "; crypt.Totp(seed,"hex","0","59",30,8,-1,"sha1")
Debug.Print "TOTP(59,sha256) "; crypt.Totp(seed32,"hex","0","59",30,8,-1,"sha256")
Debug.Print "TOTP(59,sha512) "; crypt.Totp(seed64,"hex","0","59",30,8,-1,"sha512")

Debug.Print "TOTP(1111111109,sha1) "; crypt.Totp(seed,"hex","0","1111111109",30,8,-1,"sha1")
Debug.Print "TOTP(1111111109,sha256) "; crypt.Totp(seed32,"hex","0","1111111109",30,8,-1,"sha256")
Debug.Print "TOTP(1111111109,sha512) "; crypt.Totp(seed64,"hex","0","1111111109",30,8,-1,"sha512")

Debug.Print "TOTP(1111111111,sha1) "; crypt.Totp(seed,"hex","0","1111111111",30,8,-1,"sha1")
Debug.Print "TOTP(1111111111,sha256) "; crypt.Totp(seed32,"hex","0","1111111111",30,8,-1,"sha256")
Debug.Print "TOTP(1111111111,sha512) "; crypt.Totp(seed64,"hex","0","1111111111",30,8,-1,"sha512")

Debug.Print "TOTP(1234567890,sha1) "; crypt.Totp(seed,"hex","0","1234567890",30,8,-1,"sha1")
Debug.Print "TOTP(1234567890,sha256) "; crypt.Totp(seed32,"hex","0","1234567890",30,8,-1,"sha256")
Debug.Print "TOTP(1234567890,sha512) "; crypt.Totp(seed64,"hex","0","1234567890",30,8,-1,"sha512")

Debug.Print "TOTP(2000000000,sha1) "; crypt.Totp(seed,"hex","0","2000000000",30,8,-1,"sha1")
Debug.Print "TOTP(2000000000,sha256) "; crypt.Totp(seed32,"hex","0","2000000000",30,8,-1,"sha256")
Debug.Print "TOTP(2000000000,sha512) "; crypt.Totp(seed64,"hex","0","2000000000",30,8,-1,"sha512")

Debug.Print "TOTP(20000000000,sha1) "; crypt.Totp(seed,"hex","0","20000000000",30,8,-1,"sha1")
Debug.Print "TOTP(20000000000,sha256) "; crypt.Totp(seed32,"hex","0","20000000000",30,8,-1,"sha256")
Debug.Print "TOTP(20000000000,sha512) "; crypt.Totp(seed64,"hex","0","20000000000",30,8,-1,"sha512")

' Note: To compute the TOTP using the current system date/time, pass an empty string instead of an explicit time.
' For example:
Debug.Print "TOTP(CurrentSystemTime,sha1) "; crypt.Totp(seed,"hex","0","",30,8,-1,"sha1")
Debug.Print "TOTP(CurrentSystemTime,sha256) "; crypt.Totp(seed32,"hex","0","",30,8,-1,"sha256")
Debug.Print "TOTP(CurrentSystemTime,sha512) "; crypt.Totp(seed64,"hex","0","",30,8,-1,"sha512")