Change update password.
Update password is used for entering update mode, where firmware
could be uploaded using dfu-programmer or other means.
Storage only
@param current_update_password 20 characters
@param new_update_password 20 characters
@return command processing error code
Connects to the device with given ID. ID’s list could be created with NK_list_devices_by_cpuID.
Requires calling to NK_list_devices_by_cpuID first. Connecting to arbitrary ID/USB path is not handled.
On connection requests status from device and disconnects it / removes from map on connection failure.
Storage only
@param id Target device ID (example: ‘00005d19:dacc2cb4_p_0001:0010:02’)
@return 1 on successful connection, 0 otherwise
Connects to a device with the given path. The path is a USB device
path as returned by hidapi.
@param path the device path
@return 1 on successful connection, 0 otherwise
Create hidden volume.
Requires encrypted volume to be unlocked.
Storage only
@param slot_nr slot number in range 0-3
@param start_percent volume begin expressed in percent of total available storage, int in range 0-99
@param end_percent volume end expressed in percent of total available storage, int in range 1-100
@param hidden_volume_password 20 characters
@return command processing error code
Return the device’s serial number string as an integer. Use
NK_last_command_status to check for an error if this function
returns zero.
@return device’s serial number as an integer
Enter update mode. Needs update password.
When device is in update mode it no longer accepts any HID commands until
firmware is launched (regardless of being updated or not).
Smartcard (through CCID interface) and its all volumes are not visible as well.
Its VID and PID are changed to factory-default (03eb:2ff1 Atmel Corp.)
to be detected by flashing software. Result of this command can be reversed
by using ‘launch’ command.
For dfu-programmer it would be: ‘dfu-programmer at32uc3a3256s launch’.
Storage only
@param update_password 20 characters
@return command processing error code
Fill SD card with random data.
Should be done on first stick initialization after creating keys.
Storage only
@param admin_pin 20 characters
@return command processing error code
Authenticates the user on ADMIN privilages with admin_password and sets user’s temporary password on device to admin_temporary_password.
@param admin_password char[25] current administrator PIN
@param admin_temporary_password char[25] admin temporary password to be set on device for further communication (authentication command)
@return command processing error code
Get SD card usage attributes. Usable during hidden volumes creation.
If the command was successful (return value 0), the usage data is
written to the output pointer’s target. The output pointer must
not be null.
Storage only
@param out the output pointer for the usage data
@return command processing error code
Get HOTP code from the device (PIN protected)
@param slot_number HOTP slot number, slot_number<3
@param user_temporary_password char[25] user temporary password if PIN protected OTP codes are enabled,
otherwise should be set to empty string - ‘’
@return HOTP code
Get last command processing status. Useful for commands which returns the results of their own and could not return
an error code.
@return previous command processing error code
Get the library version as a string. This is the output of
git describe --always at compile time, for example “v3.3” or
“v3.3-19-gaee920b”.
The return value is a string literal and must not be freed.
@return the library version as a string
Get password safe slots’ status
The return value must be freed using NK_free_password_safe_slot_status.
@return uint8_t[16] slot statuses - each byte represents one slot with 0 (not programmed) and 1 (programmed)
Get the stick status common to all Nitrokey devices and return the
command processing error code. If the code is zero, i. e. the
command was successful, the storage status is written to the output
pointer’s target. The output pointer must not be null.
Get the Storage stick status and return the command processing
error code. If the code is zero, i. e. the command was successful,
the storage status is written to the output pointer’s target.
The output pointer must not be null.
Get TOTP code from the device (PIN protected)
@param slot_number TOTP slot number, slot_number<15
@param challenge TOTP challenge – unused
@param last_totp_time last time – unused
@param last_interval last interval – unused
@param user_temporary_password char[25] user temporary password if PIN protected OTP codes are enabled,
otherwise should be set to empty string - ‘’
@return TOTP code
Returns a linked list of all connected devices, or null if no devices
are connected or an error occured. The linked list must be freed by
calling NK_free_device_info.
@return a linked list of all connected devices
Connect to device of given model. Currently library can be connected only to one device at once.
@param device_model char ‘S’: Nitrokey Storage, ‘P’: Nitrokey Pro
@return 1 if connected, 0 if wrong model or cannot connect
Connect to device of given model. Currently library can be connected only to one device at once.
@param device_model NK_device_model: NK_PRO: Nitrokey Pro, NK_STORAGE: Nitrokey Storage, NK_LIBREM: Librem Key
@return 1 if connected, 0 if wrong model or cannot connect
Get currently set config - status of function Numlock/Capslock/Scrollock OTP sending and is enabled PIN protected OTP
The return value must be freed using NK_free_config.
@see NK_write_config
@return uint8_t general_config[5]:
uint8_t numlock;
uint8_t capslock;
uint8_t scrolllock;
uint8_t enable_user_password;
uint8_t delete_user_password;
Get currently set config and write it to the given pointer.
@see NK_read_config
@see NK_write_config_struct
@param out a pointer to the struct that should be written to
@return command processing error code
Make encrypted volume read-only.
Device hides encrypted volume for a second therefore make sure
buffers are flushed before running.
Firmware range: v0.49 only, future (see firmware release notes)
Storage only
@param admin_pin 20 characters
@return command processing error code
Make encrypted volume read-write.
Device hides encrypted volume for a second therefore make sure
buffers are flushed before running.
Firmware range: v0.49 only, future (see firmware release notes)
Storage only
@param admin_pin 20 characters
@return command processing error code
Make unencrypted volume read-only.
Device hides unencrypted volume for a second therefore make sure
buffers are flushed before running.
Does nothing if firmware version is not matched
Firmware range: Storage v0.50, v0.48 and below
Storage only
@param user_pin 20 characters User PIN
@return command processing error code
Make unencrypted volume read-only.
Device hides unencrypted volume for a second therefore make sure
buffers are flushed before running.
Does nothing if firmware version is not matched
Firmware range: Storage v0.49, v0.51+
Storage only
@param admin_pin 20 characters Admin PIN
@return command processing error code
Make unencrypted volume read-write.
Device hides unencrypted volume for a second therefore make sure
buffers are flushed before running.
Does nothing if firmware version is not matched
Firmware range: Storage v0.50, v0.48 and below
Storage only
@param user_pin 20 characters User PIN
@return command processing error code
Make unencrypted volume read-write.
Device hides unencrypted volume for a second therefore make sure
buffers are flushed before running.
Does nothing if firmware version is not matched
Firmware range: Storage v0.49, v0.51+
Storage only
@param admin_pin 20 characters Admin PIN
@return command processing error code
Function to determine unencrypted volume PIN type
@param minor_firmware_version
@return Returns 1, if set unencrypted volume ro/rw pin type is User, 0 otherwise.
Return the debug status string. Debug purposes. This function is
deprecated in favor of NK_get_status_as_string.
@return string representation of the status or an empty string
if the command failed
Set the device time used for TOTP to the given time. Contrary to
{@code set_time(uint64_t)}, this command fails if {@code old_time}
> {@code time} or if {@code old_time} is zero (where {@code
old_time} is the current time on the device).
Authenticates the user on USER privilages with user_password and sets user’s temporary password on device to user_temporary_password.
@param user_password char[25] current user password
@param user_temporary_password char[25] user temporary password to be set on device for further communication (authentication command)
@return command processing error code
Write general config to the device
@param numlock set value in range [0-1] to send HOTP code from slot ‘numlock’ after double pressing numlock
or outside the range to disable this function
@param capslock similar to numlock but with capslock
@param scrolllock similar to numlock but with scrolllock
@param enable_user_password set True to enable OTP PIN protection (require PIN each OTP code request)
@param delete_user_password (unused)
@param admin_temporary_password current admin temporary password
@return command processing error code
Write general config to the device
@param config the configuration data
@param admin_temporary_password current admin temporary password
@return command processing error code
Write TOTP slot data to the device
@param slot_number TOTP slot number, slot_number<15, 0-numbered
@param slot_name char[15] desired slot name. C string (requires ending ‘\0’; 16 bytes).
@param secret char[40] 160-bit or 320-bit (currently Pro v0.8 only) secret as a hex string. C string (requires ending ‘\0’; 41 bytes).
See NitrokeyManager::is_320_OTP_secret_supported.
@param time_window uint16_t time window for this TOTP
@param use_8_digits should returned codes be 6 (false) or 8 digits (true)
@param use_enter press ENTER key after sending OTP code using double-pressed scroll/num/capslock
@param use_tokenID @see token_ID
@param token_ID @see https://openauthentication.org/token-specs/, ‘Class A’ section
@param temporary_password char[20] admin temporary password
@return command processing error code
Callback function for NK_set_log_function. The first argument is
the log level (0 = Error, 1 = Warn, 2 = Info, 3 = DebugL1,
4 = Debug, 5 = DebugL2) and the second argument is the log message.