Change PIN Command
This command allows the user to update either the PIN command or the PUK code. The update can occur only under secure conditions and with proper authentication. This command ensures the integrity and security of the authentication system.
def change_pin(new_pin: str):
card.change_pin(new_pin)
# For example:
change_pin("132456122")
def change_puk(current_puk: str, new_puk: str):
card.change_puk(current_puk, new_puk)
# For example:
change_puk("09875789012", "01591789012")
Change PIN Command: Understanding APDU Components
The following table outlines the components of the Application Protocol Data Unit (APDU).Â
Field | Description | Value |
CLA | This field specifies the class of the instruction. | 0x80 |
INS | This field specifies the particular command or operation that the smart card or secure element should execute. | 0x21 |
P1 | First parameter of the instruction that specifies the details about the operation being requested. | PIN/PUK selector |
P2 | First parameter of the instruction that specifies additional details about the operation being requested. | 0x00 |
Data | Key data | The new PIN/PUK |
Note
- This command is available only after Secure Channel has been established.
- To change the PIN:
- The user must be PIN-authenticated, OR
- The current PUK must be provided in the payload.
- To change the PUK, both the new PUK and current PUK must be provided.
- If authentication is not fulfilled correctly, the change fails.
Input Validation Rules
- PIN command must be:
- 9 characters
- Start with at least 4 digits (‘0’–’9’)
- Padded with 0x00 to reach 9 bytes if fewer than 9 digits are used
- PUK must be:
- 12 characters long
- Exactly 24 bytes when changing PUK (NewPUK + CurrentPUK)
Data Field Format
Condition | Data Value |
P1 = 0x00 (Change PIN) | If PIN Command is already verified: If PIN is not verified (e.g., forgotten): |
P1 = 0x01 (Change PUK) | Data = newPUK (12 bytes) + currentPUK (12 bytes) |
Response
The following table outlines the possible responses that you will receive:
Response Code | Description |
0x9000 | Success |
0x6A80 | Invalid PIN/PUK format |
0x6985 | PIN Command not validated or card not initialized |
0x9840 | Invalid PUK when attempting to change PIN with it |
0x63Cx | Remaining PIN tries (x indicates attempts left); resets any user session |
Product Documentation
Admin Commands
Signature Commands