CMAC signature in the NFC applet

VivoKey Apex
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Today I was reading the API docs ( Verify API - VivoKey Technologies ) and I wanted to try the CMAC signature trick.

My understanding is that if I write any record including the string {AES128_CMAC_SIGNATURE_XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX} when I read it, it will magically show the salted signature, correct?

I tried on my apex, but when I read my new record with TagInfo I still see the long series of X, no magic signature. I guess this means I have an older version of the applet? Or I misunderstood the workflow?

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Screenshot_20251018-132045
Screenshot_20251018-1320451080×2400 201 KB

It seems to work for me. But only on the last record containing the token. After writing this text record, i have three ndef records on this apex.

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Thanks for the test! i think I gotta update

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A good test URL is the one from the API docs;

https://vivokey.com/demo/sigtest/?s={AES128_CMAC_SIGNATURE_XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX}

This URL will take the signature received and use our test API key with the API to obtain validated unsigned JSON from /validate.json (so it’s readable). If you prefer the signed JWT just use /validate in your own solution.

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I confirm I just needed to uodate: alas! old cyborgs and their outdated software

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