topic Re: Can't execute ChangeSettings Command on NTAG 424 in NFC

undefined

undefined — Thu, 14 Dec 2023 04:25:57 GMT

undefined

Re: Can't execute ChangeSettings Command on NTAG 424

Kan_Li — Tue, 02 Feb 2021 09:21:09 GMT

Hello @undefined ,

We provide an example in the following link:

https://www.nxp.com/docs/en/application-note/AN12196.pdf

Please refer to section 6 for details.

Hope that helps,

Have a great day,

Kan

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Re: Can't execute ChangeSettings Command on NTAG 424

undefined — Thu, 14 Dec 2023 04:25:46 GMT

undefined

Re: Can't execute ChangeSettings Command on NTAG 424

Jonathan_Iglesias — Tue, 16 Feb 2021 18:54:49 GMT

Hi @undefined ,

Hope you are doing great,

Please accept our apologies for the delay there is an important holiday in my colleague country and that is why there is a little delay in our response, regarding your issue, that error means that the key used to authenticate is not the correct one to modify the file settings, basically whatever you have in your change key settings for the file is the one, I would recommend to double check the process I see you have the settings as E0EE which should require an authentication with key 00 to modify the file settings, also please first select the application then authenticate. you can check the IV values in your process, that you are using the correct key, and confirm the file settings, check the following log I created for you doing the Select command>Authenticate with key 01 ( since my card had the settings: Read 00 write 01 Read/Write 03 and change 01) > get file settings > change file settings

SELECT command Send to card: 00A4040C07D276000085010100 Recv from card: 9000 Authenticate EV2 first Send to card: 9071000002010000 Recv from card: 739CC6604B45430E602EC5283139F1FE91AF PICC-to->PCD E(Kx, RndB): 739CC6604B45430E602EC5283139F1FE Plain RNDB = 65EAF88FAF5290623DDCE478ADBE0BC4 Plain RNDA = 25E559236536A90860A28C6571F9F913 Plain RndB'= 60A28C6571F9F913EAF88FAF5290623DDCE478ADBE0BC465 Plain (RndA || RndB')= 25E559236536A90860A28C6571F9F913EAF88FAF5290623DDCE478ADBE0BC465 Encrypted (RndA || RndB'): 1EAC3CCD71A607FA2D474B4845721ADA12F20F9B63C92E1603D630EBA4B9B830 Send to card: 90AF0000201EAC3CCD71A607FA2D474B4845721ADA12F20F9B63C92E1603D630EBA4B9B83000 Recv from card: 4E4F4614CA94263B65E18D31FA6F34C15BFC7C4C499B3FDA90EA8B50A373BFEC9100 PICC-to->PCD E(Kx, TI||RndA'||PDcap2||PCDcap2): 4E4F4614CA94263B65E18D31FA6F34C15BFC7C4C499B3FDA90EA8B50A373BFEC Plain (TI || RndA' || PDcap2 || PCDcap2)= FB72B311E559236536A90860A28C6571F9F91325000000000000000000000000 Plain RNDA' = SV1 = 0xA5||0x5A||0x00||0x01||0x00||0x80||RndA[15..14]||(RndA[13..8] ⊕ RndB[15..10])||RndB[9..0]||RndA[7..0] SV1 = A55A0001008025E53CC99DB9065A90623DDCE478ADBE0BC460A28C6571F9F913 Encrypted SessionEncKey = AF479E5DFD0B91E1E0B364CB41746088 SV2 = 0x5A||0xA5||0x00||0x01||0x00||0x80||RndA[15..14]||(RndA[13..8] ⊕ RndB[15..10])||RndB[9..0]||RndA[7..0] SV2 = 5AA50001008025E53CC99DB9065A90623DDCE478ADBE0BC460A28C6571F9F913 Encrypted SessionMacKey = 795A1CF5300943E758AF53BD5FE5E769 CmdCtr = 0000 Get file settings IV = 00000000000000000000000000000000 MAC Input Data = Cmd || CmdCtr || TI || CmdHeader || E(CmdData) MAC Input Data = F50000FB72B31102 MAC = E2D5F311756E933104D85618A1EE7207 Send to card: 90F500000902D5116E31D818EE0700 Recv from card: 00003102000100BCC4DE8C5817369D9100 IV = 00000000000000000000000000000000 MAC Input Data = Cmd || CmdCtr || TI || CmdHeader || E(CmdData) MAC Input Data = 000100FB72B31100003102000100 MAC = 2CBC83C49ADEAC8CA25838175036719D phalMfNtag42XDna_GetFileSettings--------LEAVE-------- pFSBuffer=00003102000100 bBufferLen=07 [STATUS = SUCCESS] phalMfNtag42XDna_ChangeFileSettings--------ENTRY-------- bCommMode=30 bFileNo=02 bFileOption=00 bAdditionalInfoLen=00 pAccessRights=3102 Change file settings: plain stream(in): plain= A55AFB72B31101000000000000000000 Encrypted stream(out): enc= 596A58A577257242F81A425E74FB5F9D IV = 596A58A577257242F81A425E74FB5F9D plain stream(in): plain= 00310280000000000000000000000000 Encrypted stream(out): enc= C559F8442B9FD87636A54D09397553F3 IV = 00000000000000000000000000000000 MAC Input Data = Cmd || CmdCtr || TI || CmdHeader || E(CmdData) MAC Input Data = 5F0100FB72B31102C559F8442B9FD87636A54D09397553F3 MAC = 74E5F7EA2FF190BD1102D2EA55434D0B Send to card: 905F00001902C559F8442B9FD87636A54D09397553F3E5EAF1BD02EA430B00 Recv from card: 1EE98E904AE6AACD9100 IV = 00000000000000000000000000000000 MAC Input Data = Cmd || CmdCtr || TI || CmdHeader || E(CmdData) MAC Input Data = 000200FB72B311 MAC = 751E34E99C8EC490E24A82E683AA91CD

Jonathan

Re: Can't execute ChangeSettings Command on NTAG 424

Kan_Li — Thu, 18 Feb 2021 05:54:07 GMT

Hello @Jonathan_Iglesias ,

Thanks for the following up!

Hello @undefined ,

Is there any progress on your side? I have checked with the expert, and he recommended not using “80” at the end of ChangeFileSettings Data: 4000E0C1F12120000043000043000080

and he can get APDU with your settings:

905F0000190295DA3AAB53AABA618E20BFC140208CD7238DC0733225B78B00

Have a great day,
Kan

Re: Can't execute ChangeSettings Command on NTAG 424

undefined — Thu, 14 Dec 2023 04:25:39 GMT

undefined

Re: Can't execute ChangeSettings Command on NTAG 424

Kan_Li — Mon, 22 Feb 2021 07:45:34 GMT

Hello @undefined ,

Yes it is AES-128 cipher. 80h is indeed used for padding, but it is not part of Change File Settings, that’s why it is mentioned.

- Maybe problem is with CmdCtr, can you print out command counters at each command after authentication?
- Is it possible to share exact order? Because --SELECT APPLICATION-- cannot be done after --AUTHENTICATE EV2 FIRST--.

Have a great day,
Kan

Re: Can't execute ChangeSettings Command on NTAG 424

undefined — Thu, 14 Dec 2023 04:25:30 GMT

undefined

Re: Can't execute ChangeSettings Command on NTAG 424

Kan_Li — Fri, 26 Feb 2021 08:30:10 GMT

Hello @undefined ,

No, the actual value of the CmdCtr is never transmitted. The CmdCtr is reset to 0000h at PCD and
PICC after a successful AuthenticateEV2First authentication and it is maintained as long as the PICC remains authenticated. Please kindly refer to "9.1.2 Command Counter" of the data sheet for more details.

Have a great day,
Kan

Re: Can't execute ChangeSettings Command on NTAG 424

undefined — Thu, 14 Dec 2023 04:26:12 GMT

undefined

Re: Can't execute ChangeSettings Command on NTAG 424

curdin — Thu, 13 Jan 2022 04:54:26 GMT

Hi @undefined ,

I'm running into the same issue, using the same node setup.

Can you share more information on how you computed the SV1 and SV2 values please? Did you set the CmdCtr to 0000 when computing them?

Any help appreciated!