vos/ambiq-hal-sys/ambiq-sparkfun-sdk/mcu/apollo3p/hal/am_hal_security.c
2022-10-23 23:45:43 -07:00

405 lines
13 KiB
C

//*****************************************************************************
//
// am_hal_security.c
//! @file
//!
//! @brief Functions for on-chip security features
//!
//! @addtogroup
//! @ingroup apollo3phal
//! @{
//
//*****************************************************************************
//*****************************************************************************
//
// Copyright (c) 2020, Ambiq Micro
// All rights reserved.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are met:
//
// 1. Redistributions of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// 2. Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in the
// documentation and/or other materials provided with the distribution.
//
// 3. Neither the name of the copyright holder nor the names of its
// contributors may be used to endorse or promote products derived from this
// software without specific prior written permission.
//
// Third party software included in this distribution is subject to the
// additional license terms as defined in the /docs/licenses directory.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
// POSSIBILITY OF SUCH DAMAGE.
//
// This is part of revision 2.4.2 of the AmbiqSuite Development Package.
//
//*****************************************************************************
#include <stdint.h>
#include <stdbool.h>
#include "am_mcu_apollo.h"
// Local defines
// Maximum iterations for hardware CRC to finish
#define MAX_CRC_WAIT 100000
#define AM_HAL_SECURITY_LOCKSTAT_CUSTOMER 0x1
#define AM_HAL_SECURITY_LOCKSTAT_RECOVERY 0x40000000
// Global declaration
// These are declared as ptr variables to avoid an issue with GCC reading from location 0x0.
const volatile uint32_t *g_pFlash0 = (uint32_t*)(AM_HAL_SBL_ADDRESS + 0);
const volatile uint32_t *g_pFlash4 = (uint32_t*)(AM_HAL_SBL_ADDRESS + 4);
//*****************************************************************************
//
//! @brief Hardcoded function - to Run supplied main program
//!
//! @param r0 = vtor - address of the vector table
//!
//! @return Returns None
//
//*****************************************************************************
#if (defined (__ARMCC_VERSION)) && (__ARMCC_VERSION < 6000000)
static __asm void
bl_run_main(uint32_t *vtor)
{
//
// Store the vector table pointer of the new image into VTOR.
//
movw r3, #0xED08
movt r3, #0xE000
str r0, [r3, #0]
//
// Load the new stack pointer into R1 and the new reset vector into R2.
//
ldr r3, [r0, #0]
ldr r2, [r0, #4]
//
// Set the stack pointer for the new image.
//
mov sp, r3
//
// Jump to the new reset vector.
//
bx r2
}
#elif (defined (__ARMCC_VERSION)) && (__ARMCC_VERSION >= 6000000)
__attribute__((naked))
static void
bl_run_main(uint32_t *vtor)
{
__asm
(
" movw r3, #0xED08\n\t" // Store the vector table pointer of the new image into VTOR.
" movt r3, #0xE000\n\t"
" str r0, [r3, #0]\n\t"
" ldr r3, [r0, #0]\n\t" // Load the new stack pointer into R1 and the new reset vector into R2.
" ldr r2, [r0, #4]\n\t"
" mov sp, r3\n\t" // Set the stack pointer for the new image.
" bx r2\n\t" // Jump to the new reset vector.
);
}
#elif defined(__GNUC_STDC_INLINE__)
__attribute__((naked))
static void
bl_run_main(uint32_t *vtor)
{
__asm
(
" movw r3, #0xED08\n\t" // Store the vector table pointer of the new image into VTOR.
" movt r3, #0xE000\n\t"
" str r0, [r3, #0]\n\t"
" ldr r3, [r0, #0]\n\t" // Load the new stack pointer into R1 and the new reset vector into R2.
" ldr r2, [r0, #4]\n\t"
" mov sp, r3\n\t" // Set the stack pointer for the new image.
" bx r2\n\t" // Jump to the new reset vector.
);
}
#elif defined(__IAR_SYSTEMS_ICC__)
__stackless static inline void
bl_run_main(uint32_t *vtor)
{
__asm volatile (
" movw r3, #0xED08\n" // Store the vector table pointer of the new image into VTOR.
" movt r3, #0xE000\n"
" str r0, [r3, #0]\n"
" ldr r3, [r0, #0]\n" // Load the new stack pointer into R1 and the new reset vector into R2.
" ldr r2, [r0, #4]\n"
" mov sp, r3\n" // Set the stack pointer for the new image.
" bx r2\n" // Jump to the new reset vector.
);
}
#else
#error Compiler is unknown, please contact Ambiq support team
#endif
//*****************************************************************************
//
//! @brief Get Device Security Info
//!
//! @param pSecInfo - Pointer to structure for returned security info
//!
//! This will retrieve the security information for the device
//!
//! @return Returns AM_HAL_STATUS_SUCCESS on success
//
//*****************************************************************************
uint32_t am_hal_security_get_info(am_hal_security_info_t *pSecInfo)
{
if (!pSecInfo)
{
return AM_HAL_STATUS_INVALID_ARG;
}
pSecInfo->info0Version = AM_REGVAL(0x50020040);
pSecInfo->bInfo0Valid = MCUCTRL->SHADOWVALID_b.INFO0_VALID;
if (MCUCTRL->BOOTLOADER_b.SECBOOTFEATURE)
{
uint32_t status;
uint32_t sblVersion;
uint32_t (*pFuncVersion)(uint32_t *) = (uint32_t (*)(uint32_t *))(AM_HAL_SBL_ADDRESS + 0x1D1);
status = pFuncVersion(&sblVersion);
if (status != AM_HAL_STATUS_SUCCESS)
{
return status;
}
pSecInfo->sblVersion = sblVersion & 0x7FFF;
pSecInfo->sblVersionAddInfo = sblVersion >> 15;
return AM_HAL_STATUS_SUCCESS;
}
else
{
// No SBL Pre-installed
return AM_HAL_STATUS_FAIL;
}
}
//*****************************************************************************
//
//! @brief Set the key for specified lock
//!
//! @param lockType - The lock type to be operated upon
//! @param pKey - Pointer to 128b key value
//!
//! This will program the lock registers for the specified lock and key
//!
//! @return Returns AM_HAL_STATUS_SUCCESS on success
//
//*****************************************************************************
uint32_t am_hal_security_set_key(am_hal_security_locktype_t lockType, am_hal_security_128bkey_t *pKey)
{
#ifndef AM_HAL_DISABLE_API_VALIDATION
if (pKey == NULL)
{
return AM_HAL_STATUS_INVALID_ARG;
}
switch (lockType)
{
case AM_HAL_SECURITY_LOCKTYPE_CUSTOMER:
case AM_HAL_SECURITY_LOCKTYPE_RECOVERY:
break;
default:
return AM_HAL_STATUS_INVALID_ARG;
}
#endif // AM_HAL_DISABLE_API_VALIDATION
SECURITY->LOCKCTRL = lockType;
SECURITY->KEY0 = pKey->keys.key0;
SECURITY->KEY1 = pKey->keys.key1;
SECURITY->KEY2 = pKey->keys.key2;
SECURITY->KEY3 = pKey->keys.key3;
return AM_HAL_STATUS_SUCCESS;
}
//*****************************************************************************
//
//! @brief Get the current status of the specified lock
//!
//! @param lockType - The lock type to be operated upon
//! @param pbUnlockStatus - Pointer to return variable with lock status
//!
//! This will get the lock status for specified lock - true implies unlocked
//! Note that except for customer lock, other locks are self-locking on status read
//!
//! @return Returns AM_HAL_STATUS_SUCCESS on success
//
//*****************************************************************************
uint32_t am_hal_security_get_lock_status(am_hal_security_locktype_t lockType, bool *pbUnlockStatus)
{
uint32_t unlockMask;
#ifndef AM_HAL_DISABLE_API_VALIDATION
if (pbUnlockStatus == NULL)
{
return AM_HAL_STATUS_INVALID_ARG;
}
#endif // AM_HAL_DISABLE_API_VALIDATION
switch (lockType)
{
case AM_HAL_SECURITY_LOCKTYPE_CUSTOMER:
unlockMask = AM_HAL_SECURITY_LOCKSTAT_CUSTOMER;
break;
case AM_HAL_SECURITY_LOCKTYPE_RECOVERY:
unlockMask = AM_HAL_SECURITY_LOCKSTAT_RECOVERY;
break;
default:
return AM_HAL_STATUS_INVALID_ARG;
}
*pbUnlockStatus = SECURITY->LOCKSTAT & unlockMask;
return AM_HAL_STATUS_SUCCESS;
}
//*****************************************************************************
//
//! @brief Compute CRC32 for a specified payload
//!
//! @param startAddr - The start address of the payload
//! @param sizeBytes - The length of payload in bytes
//! @param pCrc - Pointer to return computed CRC
//!
//! This will use the hardware engine to compute CRC32 on an arbitrary data payload
//!
//! @return Returns AM_HAL_STATUS_SUCCESS on success
//
//*****************************************************************************
uint32_t am_hal_crc32(uint32_t startAddr, uint32_t sizeBytes, uint32_t *pCrc)
{
uint32_t status;
#ifndef AM_HAL_DISABLE_API_VALIDATION
if (pCrc == NULL)
{
return AM_HAL_STATUS_INVALID_ARG;
}
// Make sure size is multiple of 4 bytes
if (sizeBytes & 0x3)
{
return AM_HAL_STATUS_INVALID_ARG;
}
// TODO - check the address
#endif // AM_HAL_DISABLE_API_VALIDATION
//
// Program the CRC engine to compute the crc
//
SECURITY->RESULT = 0xFFFFFFFF;
SECURITY->SRCADDR = startAddr;
SECURITY->LEN_b.LEN = (sizeBytes >> SECURITY_LEN_LEN_Pos);
SECURITY->CTRL_b.FUNCTION = SECURITY_CTRL_FUNCTION_CRC32;
// Start the CRC
SECURITY->CTRL_b.ENABLE = 1;
//
// Wait for CRC to finish
//
status = am_hal_flash_delay_status_change(MAX_CRC_WAIT,
(uint32_t)&SECURITY->CTRL, SECURITY_CTRL_ENABLE_Msk, 0);
if (status == AM_HAL_STATUS_SUCCESS)
{
*pCrc = SECURITY->RESULT;
}
return status;
}
//*****************************************************************************
//
//! @brief Helper function to Perform exit operations for a secondary bootloader
//!
//! @param pImage - The address of the image to give control to
//!
//! This function does the necessary security operations while exiting from a
//! a secondary bootloader program. If still open, it locks the info0 key region,
//! as well as further updates to the flash protection register.
//! It also checks if it needs to halt to honor a debugger request.
//! If an image address is specified, control is transferred to the same on exit.
//!
//! @return Returns AM_HAL_STATUS_SUCCESS on success, if no image address specified
//! If an image address is provided, a successful execution results in transfer to
//! the image - and this function does not return.
//
//*****************************************************************************
uint32_t am_hal_bootloader_exit(uint32_t *pImage)
{
uint32_t status = AM_HAL_STATUS_SUCCESS;
//
// Lock the assets
//
if ( MCUCTRL->SHADOWVALID_b.INFO0_VALID &&
MCUCTRL->BOOTLOADER_b.PROTLOCK )
{
am_hal_security_128bkey_t keyVal;
uint32_t *pCustKey = (uint32_t *)0x50021A00;
bool bLockStatus;
//
// PROTLOCK Open
// This should also mean that Customer key is accessible
// Now lock the key by writing an incorrect value
//
keyVal.keyword[0] = ~pCustKey[0];
keyVal.keyword[1] = ~pCustKey[0];
keyVal.keyword[2] = ~pCustKey[0];
keyVal.keyword[3] = ~pCustKey[0];
am_hal_security_set_key(AM_HAL_SECURITY_LOCKTYPE_CUSTOMER, &keyVal);
status = am_hal_security_get_lock_status(AM_HAL_SECURITY_LOCKTYPE_CUSTOMER, &bLockStatus);
if ((status != AM_HAL_STATUS_SUCCESS) || (bLockStatus))
{
return AM_HAL_STATUS_FAIL;
}
//
// Lock the protection register to prevent further region locking
// CAUTION!!! - Can not do AM_BFW on BOOTLOADER register as all writable bits in this register are Write 1 to clear
//
MCUCTRL->BOOTLOADER = _VAL2FLD(MCUCTRL_BOOTLOADER_PROTLOCK, 1);
//
// Check if we need to halt (debugger request)
//
if (MCUCTRL->SCRATCH0 & 0x1)
{
// Debugger wants to halt
uint32_t dhcsr = AM_REGVAL(0xE000EDF0);
// Clear the flag in Scratch register
MCUCTRL->SCRATCH0 &= ~0x1;
// Halt the core
dhcsr = ((uint32_t)0xA05F << 16) | (dhcsr & 0xFFFF) | 0x3;
AM_REGVAL(0xE000EDF0) = dhcsr;
// Resume from halt
}
}
// Give control to supplied image
if (pImage)
{
bl_run_main(pImage);
// Does not return
}
return status;
}