Possible to use install_attestation_cert.py with VSim?

[agreenbhm]

Hi Bryan,

Thanks for the excellent work on this! I'm using a slightly modified version of your VSim app (modified, per your suggestion in another issue, to allow "removing" and "inserting" the device). I'm attempting to set the AAGUID via the script in this repo "install_attestation_cert.py", but when I run it I receive the error "fido2.ctap.CtapError: CTAP error: 0x30 - NOT_ALLOWED". I've confirmed the virtual reader itself is working with the script. The message itself seems pretty clear, but I'm not sure if there is something additional I must do to that you're aware of in order to provision the virtual card to allow for setting the AAGUID, or if perhaps this is just a limitation of JCardSim. Any help is appreciated.

Thank you!

Drew Green

[agreenbhm]

I'm going to guess that, in line with the installation doc I need to set parameters to allow the vendor CTAP command in the "installApplet" method of the "VSim" class. Going to try that now.

[agreenbhm]

I was able to successfully set my AAGUID by setting parameters within the VSim app. However, I did seem to run into a bug during installation of the parameters here, specifically regarding the infoLen assignment. It seems that the assumption is that the array starts with an AID and/or other data, however that doesn't seem to be what is generated with the included Python script. The result is that the first byte of the parameters (in the array variable) is interpreted as the length of the AID (to be skipped), which in my case was 0xa8, which was larger than the number of bytes in the array altogether. When infoLen was assigned it caused an exception. It seems that perhaps if the offset is 0 then this section should be skipped. I commented-out this section and was then successful in installing the app with the appropriate parameters.

[BryanJacobs]

It's very possible that what VSim passes to the applet on install and what a real smartcard gives it are not the same. The code in the lines you linked is written for a real javacard environment on an actual javacard.

You should be able to, in VSim, give the applet the correct install parameters including the AID.

[JustinPack]

I've noticed an issue with version >21 of GPP that is incorrectly parsing TLVs. I was having almost this exact same issue but solved it by going to version 20.08.12.

[martinpaljak]

@JustinPack pls bring the issue up at a place where I could track it :)

[JustinPack]

I plan on creating an issue after work today.

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