HAL TAMP Use Cases

Initialization Sequence

@startuml participant Application as app participant "System Drivers" as driv == Initialization == app -> driv: HAL_Init() driv --> app app -> driv: Configure GPIO, NVIC driv --> app app -> driv: Configure system clock same as RTC driv --> app app -> driv: Power driver disable write\n protection on backup domain driv --> app @enduml

Functions called:

  • HAL_init()

Passive Tamper Workflow

@startuml participant Application as app participant "Tamper Driver" as tamp participant "Interruption" as int == Configuration of passive tampers == app -> tamp : HAL_TAMP_PASSIVE_SetConfig(&p_config) tamp --> app : HAL_OK app -> tamp : HAL_TAMP_PASSIVE_SetConfigTampers(tampers, &p_config) tamp --> app : HAL_OK == Start the passive tampers == app -> tamp : HAL_TAMP_PASSIVE_Start(tampers, interruption) tamp --> app: HAL_OK == Tamp IRQ handler == group Interruption mode int -> tamp : HAL_TAMP_TamperIRQHandler() end == Passive Tamper handler == group Polling mode app -> tamp: HAL_TAMP_PASSIVE_PollForEvent(tampers, timeout) tamp --> app : HAL_OK end == Stop the passive tampers == app -> tamp : HAL_TAMP_PASSIVE_Stop(tampers) tamp --> app: HAL_OK @enduml

Functions called:

Internal Tamper Handling

@startuml participant Application as app participant "Tamper Driver" as tamp participant "Interruption" as int == Configuration of internal tampers == app -> tamp : HAL_TAMP_INTERNAL_SetConfigTampers(tampers, &p_config) tamp --> app : HAL_OK == Start the internal tampers == app -> tamp : HAL_TAMP_INTERNAL_Start(tampers, interruption) tamp --> app: HAL_OK == Tamp IRQ handler == group Interruption mode int -> tamp : HAL_TAMP_TamperIRQHandler() end == internal Tamper handler == group Polling mode app -> tamp: HAL_TAMP_INTERNAL_PollForEvent(tampers, timeout) tamp --> app : HAL_OK end == Stop the internal tampers == app -> tamp : HAL_TAMP_INTERNAL_Stop(tampers) tamp --> app: HAL_OK @enduml

Functions called:

Active Tamper Sequence

@startuml participant Application as app participant "Tamper Driver" as tamp participant "Interruption" as int == Configuration of active tampers == app -> tamp : HAL_TAMP_ACTIVE_SetConfig(&p_config) tamp --> app : HAL_OK app -> tamp : HAL_TAMP_ACTIVE_SetConfigTampers(tampers_input, tamper_output, &p_config) tamp --> app : HAL_OK == Start the active tampers == app -> tamp : HAL_TAMP_ACTIVE_Start(interruption) tamp --> app: HAL_OK app -> tamp : HAL_TAMP_ACTIVE_SetSeed(&p_values) tamp --> app: HAL_OK == Tamp IRQ handler == group Interruption mode int -> tamp : HAL_TAMP_TamperIRQHandler() end == Active Tamper handler == group Polling mode app -> tamp: HAL_TAMP_ACTIVE_PollForEvent(tampers, timeout) tamp --> app : HAL_OK end == Stop the active tampers == app -> tamp : HAL_TAMP_ACTIVE_Stop() tamp --> app: HAL_OK @enduml

Functions called:

Backup Registers Usage Flow

@startuml participant Application as app participant "Tamper Driver" as tamp == Program and retrieve a value == app -> tamp : HAL_TAMP_WriteBackupRegisterValue(backup_register_index, data_32bit) app -> tamp : HAL_TAMP_ReadBackupRegisterValue(backup_register_index) tamp --> app : value @enduml

Functions called:

Device Secrets Management

@startuml participant Application as app participant "Tamper Driver" as tamp == Device secrets access == app -> tamp : HAL_TAMP_UnblockDeviceSecretsAccess() tamp --> app: HAL_OK app -> tamp : HAL_TAMP_BlockDeviceSecretsAccess() tamp --> app: HAL_OK app -> tamp : HAL_TAMP_IsBlockedDeviceSecretsAccess() tamp --> app : status == Erase device == app -> tamp : HAL_TAMP_EraseDeviceSecrets() tamp --> app: HAL_OK == Hardware Bootkey == app -> tamp : HAL_TAMP_EnableHardwareBootkeyBlock tamp --> app: HAL_OK app -> tamp : HAL_TAMP_IsEnabledHardwareBootkeyBlock tamp --> app: status @enduml

Functions called:

Monotonic Counter Operation

@startuml participant Application as app participant "Tamper Driver" as tamp == Monotonic Counter == app -> tamp : HAL_TAMP_MONOTONIC_IncrementCounter() tamp --> app: HAL_OK app -> tamp : HAL_TAMP_MONOTONIC_GetCounter() tamp --> app : value @enduml

Functions called:

Resource Protection Sequence

@startuml participant Application as app participant "Tamper Driver" as tamp == Ressources protection == app -> tamp : HAL_TAMP_EnableResourceProtection() tamp --> app: HAL_OK app -> tamp : HAL_TAMP_DisableResourceProtection() tamp --> app: HAL_OK app -> tamp : HAL_TAMP_IsEnabledResourceProtection() tamp --> app : status @enduml

Functions called: