SE - Secure Element#

Secure Element peripheral API.

Abstraction of the Secure Element's mailbox interface.

For series 2 devices with a part number that is xG23 or higher, the following step is necessary for basic operation:

Clock enable:

CMU_ClockEnable(cmuClock_SEMAILBOX, true);

Note

  • The high-level SE API has been moved to the SE manager, and the implementation in em_se should not be used.

  • Using the SE's mailbox is not thread-safe in EMLIB, and accessing the SE's mailbox both in regular and IRQ context is not safe. SE operations should be performed using the SE manager if possible.

Modules#

SE_DataTransfer_t

SE_Command_t

Deprecated Functions

Typedefs#

typedef uint32_t

Possible responses to a command.

Functions#

void
SE_addDataInput(SE_Command_t *command, SE_DataTransfer_t *data)

Add input data to a command.

void
SE_addDataOutput(SE_Command_t *command, SE_DataTransfer_t *data)

Add output data to a command.

void
SE_addParameter(SE_Command_t *command, uint32_t parameter)

Add a parameter to a command.

void
SE_executeCommand(SE_Command_t *command)

Execute the passed command.

bool

Check whether the VSE Output Mailbox is valid.

SE_getVersion(uint32_t *version)

Get current SE version.

SE_getConfigStatusBits(uint32_t *cfgStatus)

Get VSE configuration and status bits.

SE_getOTPVersion(uint32_t *otpVersion)

Get the version number of the OTP from the status field of the output mailbox.

bool

Check whether the running command has completed.

uint32_t

Read the previously executed command.

Read the status of the previously executed command.

SE_ackCommand(SE_Command_t *command)

Acknowledge and get status and output data of a completed command.

void

Wait for completion of the current command.

void
SE_disableInterrupt(uint32_t flags)

Disable one or more SE interrupts.

void
SE_enableInterrupt(uint32_t flags)

Enable one or more SE interrupts.

Macros#

#define
SE_RESPONSE_MAILBOX_INVALID 0x00FE0000UL

Root Code Mailbox is invalid.

#define
SE_RESPONSE_MAILBOX_VALID 0xE5ECC0DEUL

Root Code Mailbox magic word.

#define
SE_RESPONSE_MASK 0x000F0000UL

Response status codes for the Secure Element.

#define
SE_RESPONSE_OK 0x00000000UL

Command executed successfully or signature was successfully validated.

#define
SE_FIFO_MAX_PARAMETERS 13U

Maximum amount of parameters supported by the hardware FIFO.

#define
SE_DATATRANSFER_STOP 0x00000001UL

Stop datatransfer.

#define
SE_DATATRANSFER_DISCARD 0x40000000UL

Discard datatransfer.

#define
SE_DATATRANSFER_REALIGN 0x20000000UL

Realign datatransfer.

#define
SE_DATATRANSFER_CONSTADDRESS 0x10000000UL

Datatransfer Const Address.

#define
SE_DATATRANSFER_LENGTH_MASK 0x0FFFFFFFUL

Stop Length Mask.

#define
SE_MAX_PARAMETERS 4U

Maximum amount of parameters for largest command in defined command set.

#define
SE_DATATRANSFER_DEFAULT (address, length)

Default initialization of data transfer struct.

#define
SE_COMMAND_DEFAULT (command)

Default initialization of command struct.

Typedef Documentation#

SE_Response_t#

typedef uint32_t SE_Response_t

Possible responses to a command.


Function Documentation#

SE_addDataInput#

void SE_addDataInput (SE_Command_t * command, SE_DataTransfer_t * data)

Add input data to a command.

Parameters
TypeDirectionArgument NameDescription
SE_Command_t *[in]command

Pointer to an SE command structure.

SE_DataTransfer_t *[in]data

Pointer to a data transfer structure.

This function adds a buffer of input data to the given SE command structure The buffer gets appended by reference at the end of the list of already added buffers.

Note

  • Note that this function does not copy either the data buffer or the buffer structure, so make sure to keep the data object in scope until the command has been executed by the secure element.


SE_addDataOutput#

void SE_addDataOutput (SE_Command_t * command, SE_DataTransfer_t * data)

Add output data to a command.

Parameters
TypeDirectionArgument NameDescription
SE_Command_t *[in]command

Pointer to an SE command structure.

SE_DataTransfer_t *[in]data

Pointer to a data transfer structure.

This function adds a buffer of output data to the given command structure The buffer gets appended by reference at the end of the list of already added buffers.

Note

  • Note that this function does not copy either the data buffer or the buffer structure, so make sure to keep the data object in scope until the command has been executed by the secure element.


SE_addParameter#

void SE_addParameter (SE_Command_t * command, uint32_t parameter)

Add a parameter to a command.

Parameters
TypeDirectionArgument NameDescription
SE_Command_t *[in]command

Pointer to a filled-out SE command structure.

uint32_t[in]parameter

Parameter to add.

This function adds a parameter word to the passed command.

Note


SE_executeCommand#

void SE_executeCommand (SE_Command_t * command)

Execute the passed command.

Parameters
TypeDirectionArgument NameDescription
SE_Command_t *[in]command

Pointer to a filled-out SE command structure.

This function starts the execution of the passed command by the secure element. When started, wait for the RXINT interrupt flag, or call SE_waitCommandCompletion to busy-wait. After completion, you have to call SE_readCommandResponse to get the command's execution status.


rootIsOutputMailboxValid#

bool rootIsOutputMailboxValid (void )

Check whether the VSE Output Mailbox is valid.

Parameters
TypeDirectionArgument NameDescription
voidN/A

Returns

  • True if the VSE Output Mailbox is valid (magic and checksum OK)


SE_getVersion#

SE_Response_t SE_getVersion (uint32_t * version)

Get current SE version.

Parameters
TypeDirectionArgument NameDescription
uint32_t *[in]version

Pointer to location where to copy the version of VSE to.

This function returns the current VSE version

Returns

  • One of the SE_RESPONSE return codes: SE_RESPONSE_OK when the command was executed successfully SE_RESPONSE_INVALID_PARAMETER when an invalid parameter was passed SE_RESPONSE_MAILBOX_INVALID when the mailbox content is invalid


SE_getConfigStatusBits#

SE_Response_t SE_getConfigStatusBits (uint32_t * cfgStatus)

Get VSE configuration and status bits.

Parameters
TypeDirectionArgument NameDescription
uint32_t *[out]cfgStatus

Pointer to location to copy Configuration Status bits into.

This function returns the current VSE configuration and status bits. The following list explains what the different bits in cfgStatus indicate. A bit value of 1 means enabled, while 0 means disabled:

  • [0]: Secure boot

  • [1]: Verify secure boot certificate

  • [2]: Anti-rollback

  • [3]: Narrow page lock

  • [4]: Full page lock The following status bits can be read with VSE versions higher than 1.2.2.

  • [10]: Debug port lock

  • [11]: Device erase enabled

  • [12]: Secure debug enabled

  • [15]: Debug port register state, 1 if the debug port is locked.

Note

  • This function will check that the mailbox content is valid before reading the status bits. If the command response has already been read with a call to SE_ackCommand(), the validity check will fail, and the config status bits cannot be read before a reset has occurred.

Returns

  • One of the SE_RESPONSE return codes: SE_RESPONSE_OK when the command was executed successfully SE_RESPONSE_INVALID_PARAMETER when an invalid parameter was passed SE_RESPONSE_MAILBOX_INVALID when the mailbox content is invalid


SE_getOTPVersion#

SE_Response_t SE_getOTPVersion (uint32_t * otpVersion)

Get the version number of the OTP from the status field of the output mailbox.

Parameters
TypeDirectionArgument NameDescription
uint32_t *[out]otpVersion

Pointer to location to copy OTP version number into.

This function checks if the OTP version number flag is set in the output mailbox. If it is, the version number is writen to otpVersion pointer location. If not, it returns error response.

Returns

  • One of the SE_RESPONSE return codes.

Return values

  • SE_RESPONSE_OK: when the command was executed successfully


SE_isCommandCompleted#

bool SE_isCommandCompleted (void )

Check whether the running command has completed.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function polls the SE-to-host mailbox interrupt flag.

Returns

  • True if a command has completed and the result is available


SE_readExecutedCommand#

uint32_t SE_readExecutedCommand (void )

Read the previously executed command.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function reads the previously executed command.

Returns

  • One of the SE command words. SE_RESPONSE_MAILBOX_INVALID when the mailbox content is invalid.


SE_readCommandResponse#

SE_Response_t SE_readCommandResponse (void )

Read the status of the previously executed command.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function reads the status of the previously executed command.

Returns

  • One of the SE_RESPONSE return codes: SE_RESPONSE_OK when the command was executed successfully or a signature was successfully verified, SE_RESPONSE_INVALID_COMMAND when the command ID was not recognized, SE_RESPONSE_AUTHORIZATION_ERROR when the command is not authorized, SE_RESPONSE_INVALID_SIGNATURE when signature verification failed, SE_RESPONSE_BUS_ERROR when a bus error was thrown during the command, e.g. because of conflicting Secure/Non-Secure memory accesses, SE_RESPONSE_CRYPTO_ERROR on an internal SE failure, or SE_RESPONSE_INVALID_PARAMETER when an invalid parameter was passed SE_RESPONSE_MAILBOX_INVALID when the mailbox content is invalid


SE_ackCommand#

SE_Response_t SE_ackCommand (SE_Command_t * command)

Acknowledge and get status and output data of a completed command.

Parameters
TypeDirectionArgument NameDescription
SE_Command_t *[in]command

Pointer to an SE command structure.

This function acknowledges and gets the status and output data of a completed mailbox command. The mailbox command is acknowledged by inverting all bits in the checksum (XOR with 0xFFFFFFFF). The output data is copied into the linked list of output buffers pointed to in the given command data structure.

Returns

  • One of the SE_RESPONSE return codes.

Return values

  • SE_RESPONSE_OK: when the command was executed successfully or a signature was successfully verified,

  • SE_RESPONSE_INVALID_COMMAND: when the command ID was not recognized,

  • SE_RESPONSE_AUTHORIZATION_ERROR: when the command is not authorized,

  • SE_RESPONSE_INVALID_SIGNATURE: when signature verification failed,

  • SE_RESPONSE_BUS_ERROR: when a bus error was thrown during the command, e.g. because of conflicting Secure/Non-Secure memory accesses,

  • SE_RESPONSE_CRYPTO_ERROR: on an internal SE failure, or

  • SE_RESPONSE_INVALID_PARAMETER: when an invalid parameter was passed

  • SE_RESPONSE_MAILBOX_INVALID: when mailbox command not done or invalid


SE_waitCommandCompletion#

void SE_waitCommandCompletion (void )

Wait for completion of the current command.

Parameters
TypeDirectionArgument NameDescription
voidN/A

This function "busy"-waits until the execution of the ongoing instruction has completed.


SE_disableInterrupt#

void SE_disableInterrupt (uint32_t flags)

Disable one or more SE interrupts.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]flags

SE interrupt sources to disable. Use a bitwise logic OR combination of valid interrupt flags for the Secure Element module (SE_CONFIGURATION_(TX/RX)INTEN).


SE_enableInterrupt#

void SE_enableInterrupt (uint32_t flags)

Enable one or more SE interrupts.

Parameters
TypeDirectionArgument NameDescription
uint32_t[in]flags

SE interrupt sources to enable. Use a bitwise logic OR combination of valid interrupt flags for the Secure Element module (SEMAILBOX_CONFIGURATION_TXINTEN or SEMAILBOX_CONFIGURATION_RXINTEN).