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C

TOTP Authenticator: Duplicate Results of Online Tools

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Duplicates the online tool for the Google 2FA Authenticator online tools at

Chilkat C Downloads

C
#include <C_CkCrypt2.h>

void ChilkatSample(void)
    {
    HCkCrypt2 crypt;
    const char *secretKey;

    //  This example requires the Chilkat API to have been previously unlocked.
    //  See Global Unlock Sample for sample code.
    //  
    //  Note: This example was written on 7-March-2020.  If the online tools have since changed, the instructions provided here may no longer be valid.
    //  

    crypt = CkCrypt2_Create();

    //  ---------------------------------------------------------------------------------------------
    //  To duplicate the results of the Authenticator Test at https://rootprojects.org/authenticator/
    //  do the following:
    //  1) At the bottom of the screen you will see a URI such as:
    //  
    //     otpauth://totp/ACME%20Co:john@example.com?secret=HXDMVJECJJWSRB3HWIZR4IFUGFTMXBOZ&issuer=ACME%20Co&algorithm=SHA1&digits=6&period=30
    //  
    //     Use the uppercase secret.  For example:
    secretKey = "HXDMVJECJJWSRB3HWIZR4IFUGFTMXBOZ";

    //  2) DO NOT cick the "Regenerate" button.  The regenerate button will generate a new secret.
    //  
    //  3) Run the following code to generate your 6-digit token.  Compare with the token shown in the picture of the iPhone at https://rootprojects.org/authenticator/
    //       Note: A new token is generated every 30 seconds.  You must generate within the same 30 second interval to get the same result.
    printf("Your token is: %s\n",CkCrypt2_totp(crypt,secretKey,"base32","0","",30,6,-1,"sha1"));

    //  ---------------------------------------------------------------------------------------------
    //  To duplicate the results of the Google2FA Playground at https://pragmarx.com/playground/google2fa#/
    //  do the following:

    //  1) Copy the 64-byte secret key:
    secretKey = "OR2VQTRVHB2HO2LCGVWXQSCDK5ZHQS2D3THQ6UXO57XIE7ZHOWS6HDPQ622GU747";

    //  2) Run the same code:
    //     (Note: The online tool generates a new result every 30 seconds.  You must generate and compare within the same 30-second interval.)
    printf("Your token is: %s\n",CkCrypt2_totp(crypt,secretKey,"base32","0","",30,6,-1,"sha1"));


    CkCrypt2_Dispose(crypt);

    }