LABVIEW HMAC-SHA1 implementation

Hello all,
We have need of an HMAC-SHA1 implementation in Labview. Can anyone help?
Thanks,
Josh

Hello Josh,
We have a Community example that uses HMAC-SHA1 that might help you get started.  
SHA-1 Cryptographic Hash Function
Searching the Community Code Exchange might be a good place to find additional code that has implemented HMAC-SHA1 in LabVIEW.
Regards,
M. Whitaker
ni.com/support

Similar Messages

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    Not sure whether I'm in the correct forum...
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      EXPORTING
        generate_random_key         = ' '
        alg                         = 'SHA1'
        keycstr                     = 'cB1phTHISISATESTVuZMDmWCz1CEMy82iBC3HgFLpE&7857T...YFqV93gRJQ'
        client_independent          = ' '
      EXCEPTIONS
        unknown_alg                 = 1
        param_length_error          = 2
        internal_error              = 3
        param_missing               = 4
        malloc_error                = 5
        abap_caller_error           = 6
        base64_error                = 7
        calc_hmac_error             = 8
        rsec_record_access_denied   = 9
        rsec_secstore_access_denied = 10
        rsec_error                  = 11
        rng_error                   = 12
        record_number_error         = 13
        OTHERS                      = 14.
    Best regards, Uwe
    Edited by: Julius Bussche on Aug 5, 2010 10:19 PM
    I truncated the key further because in a coding tag it toasts the formatting when too long.

    Hi,
    yes, we can :-). Let say that SAP implementation supports a key with size more than 81 bytes. Then according to specification if the key is longer than block size of hash function (64 bytes for SHA-1) then it would use hash function to reduce original key to new key with size equals to output size of hash function (20 bytes for SHA-1). Therefore doing this step manually before calling SET_HMAC_KEY is equal to calling SET_HMAC_KEY which supports keys longer than 81 bytes.
    The easiest way how to check this is to compare some HMAC-SHA1 implementation with the result produced by my proposed logic.
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            key_str TYPE string,
            hash TYPE hash160x,
            key TYPE xstring,
            hmac TYPE hash512_base_64.
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          alg        = 'SHA1'
          data       = text
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          hmacbase64 = hmac.
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    Javascript version
    var hmac = Crypto.HMAC(Crypto.SHA1, "Message", "Secret Passphrase");
    var hmacBytes = Crypto.HMAC(Crypto.SHA1, "Message", "Secret Passphrase", { asBytes: true });
    var hmacString = Crypto.HMAC(Crypto.SHA1, "Message", "Secret Passphrase", { asString: true });
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    Cheers
    Sorry for formatting but it looks like something is broken.
    Edited by: Martin Voros on Aug 6, 2010 10:34 PM

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    Hi,
    I'm sorry but this problem do need to be post at Windows Server forum, please access to the link below to post your question at Windows Server Forum:
    https://social.technet.microsoft.com/Forums/sharepoint/en-US/home?category=windowsserver
    Please remember to mark the replies as answers if they help, and unmark the answers if they provide no help. If you have feedback for TechNet Support, contact [email protected]

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