Trouble enabling read and write password verification

[dlrobers]

Posted on February 25, 2014 at 21:26

Update:

It looks like you do have to send the write password with the verify command before calling the enable or disable verification commands when modifying either the read or write permissions. You can then change the password with

the change reference data command for either permission after verifying the write password again. If I understand correctly, the only time you would need to send the read password via the verify command is when accessing a NDEF file that has the read permission verification enabled. Hopefully someone can clarify this.

The only other issue I am experiencing is that even when read and write verification is disabled (CC file reports 0x00 for both), the M24SR Demo android application says that a password is required when trying to lock read or write access under tools within the application, but not when actually reading or writing to the NFC tag. Strangely, when trying this with another M24SR that has never had file permissions modified, the app locks and unlocks read and write access without a problem. Is this a bug within the app or is there a way to clear this password? Thanks --------- Old: Kept for reference-------- I am having trouble enabling the read protection of an NDEF file through I2C. Interestingly, I can enable the write protection without any problem. Below is my series of commands for enabling the read protection. Note that the CRC values are omitted because they are generated at runtime. NDEF Tag Application Select Result 0x90 0x00 NDEF File Select Result 0x90 00 Check whether or not read verification is required using the ''Verify'' command. 0x02, 0x00, 0x20, 0x00, 0x01, 0x00 Result 0x90 0x00 //no read verification required Send test read password 0x02, 0x00, 0x20, 0x00, 0x01, 0x10, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 Result 0x90, 0x00 //Success or password matches Enable Verification Requirement 0x02, 0x00, 0x28, 0x00, 0x01 Result: 0x69 0x82 //Security status not satisfied These same series of commands work for setting the write password without a problem, in which I can then successfully modify it using the change reference data command.  On page 44 of the datasheet regarding the ''Enable Verification Requirement'' command , it says ''Before sending this command, the verify command with the correct NDEF write password shall be issued.'' What I dont understand is how are you supposed to apply a read password using the verify command when it is required to send the write password using the same command before you can call the ''Enable Verification'' command. Has anyone had any success with this? Thanks #app #m24sr #password #password #android #m24sr

[Anais GALLIGANI]

Posted on March 05, 2014 at 11:58

Hello,

Concerning the first item  

It looks like you do have to send the

write

password with the verify command before calling the enable or disable verification commands when modifying

either

the read or write permissions. You can then change the password with the change reference data command for either permission after verifying the

write

password again. If I understand correctly, the only time you would need to send the read password via the verify command is when accessing a NDEF file that has the read permission verification enabled. Hopefully someone can clarify this.

• Present the write password is a pre requirement before to modify a protection setting .

• If you just use the protection , present the dedicated password  (read or write) before acting .

Have a nice day, Best Regards, ST NFC/RFID Dynamic tag e2e support

[Anais GALLIGANI · Accepted solution]

Posted on March 05, 2014 at 15:43Hello,Concerning the second item : 

The only other issue I am experiencing is that even when read and write verification is disabled (CC file reports 0x00 for both), the M24SR Demo android application says that a password is required when trying to lock read or write access under tools within the application, but not when actually reading or writing to the NFC tag. Strangely, when trying this with another M24SR that has never had file permissions modified, the app locks and unlocks read and write access without a problem. Is this a bug within the app or is there a way to clear this password

It seems that you want to remove read/write lock, correct? 

• To do so (read un-lock for example), it is need to to go under tools panel 

  • set the switch button in front of ‘Lock Read Accessâ€� button to Off State,

  • press “Lock Read Accessâ€� button. 

  • The previous Read and Write password are requested by App to remove Read Lock.

Example :

1. In case you want to set the read lock state to OFF with a  none write locked file :

• Go to tools menu

• Set the switch button in front of read lock access one to OFF

• Press Read lock Access button

• Enter the previous Read Lock Password

• Leave the Write lock password Empty (by  pressing Set)

• Tap the Tag to remove the Read Lock State.

2. In case you want to set the read lock state to OFF with a write locked file ;

• Go to tools menu

• Set the switch button in front of read lock access one to OFF

• Press Read lock Access button

• Enter the previous Read Lock Password (by  pressing Set)

• Enter the previous Write lock password (by  pressing Set)

• Tap the Tag to remove the Read Lock State.

 3. 

In case you want to set the write lock state to OFF :

• Go to tools menu

• Set the switch button in front of write lock access one to OFF

• Press Write lock Access button

• Enter the previous Write Lock Password

• Tap the Tag to remove the Write Lock State

To verify that unlock succeed you can check the read lock state from the CC file.

Have a nice day,Best regards,ST NFC/RFID Dynamic tag e2e support