/** * @file * @brief Trust Protection Unit driver. */ /****************************************************************************** * Copyright (C) 2023 Maxim Integrated Products, Inc., All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * IN NO EVENT SHALL MAXIM INTEGRATED BE LIABLE FOR ANY CLAIM, DAMAGES * OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR * OTHER DEALINGS IN THE SOFTWARE. * * Except as contained in this notice, the name of Maxim Integrated * Products, Inc. shall not be used except as stated in the Maxim Integrated * Products, Inc. Branding Policy. * * The mere transfer of this software does not imply any licenses * of trade secrets, proprietary technology, copyrights, patents, * trademarks, maskwork rights, or any other form of intellectual * property whatsoever. Maxim Integrated Products, Inc. retains all * ownership rights. * ******************************************************************************/ #include "mxc_device.h" #include "mxc_errors.h" #include "mxc_assert.h" #include "mxc_sys.h" #include "aes_revb.h" #include "trng.h" #include "flc.h" #include "string.h" #define KEY_ADDR 0x10802008 #define FMV_ADDR 0x10802000 static const uint32_t fmv[2] = { 0x2B86D479, 0x2B86D479 }; static void reverse_key(const void *key, uint8_t *keyr, int len) { int i; uint8_t tmp; uint8_t *k = (uint8_t *)key; for (i = 0; i < len; i++) { tmp = k[i]; k[i] = keyr[len - i - 1]; keyr[len - i - 1] = tmp; } } /* ************************************************************************* */ /* Global Control/Configuration functions */ /* ************************************************************************* */ int MXC_AES_Init(void) { MXC_SYS_ClockEnable(MXC_SYS_PERIPH_CLOCK_AES); MXC_SYS_ClockEnable(MXC_SYS_PERIPH_CLOCK_TRNG); MXC_AES->ctrl = 0x00; // Start with a randomly generated key. MXC_AES_GenerateKey(); MXC_AES_RevB_Init((mxc_aes_revb_regs_t *)MXC_AES); return E_NO_ERROR; } void MXC_AES_EnableInt(uint32_t interrupt) { MXC_AES_RevB_EnableInt((mxc_aes_revb_regs_t *)MXC_AES, interrupt); } void MXC_AES_DisableInt(uint32_t interrupt) { MXC_AES_RevB_DisableInt((mxc_aes_revb_regs_t *)MXC_AES, interrupt); } int MXC_AES_IsBusy(void) { return MXC_AES_RevB_IsBusy((mxc_aes_revb_regs_t *)MXC_AES); } int MXC_AES_Shutdown(void) { int error = MXC_AES_RevB_Shutdown((mxc_aes_revb_regs_t *)MXC_AES); MXC_SYS_ClockDisable(MXC_SYS_PERIPH_CLOCK_AES); return error; } void MXC_AES_DMACallback(int ch, int error) { MXC_AES_RevB_DMACallback(ch, error); } void MXC_AES_GenerateKey(void) { // Generating a random key is part of the TRNG block MXC_TRNG_GenerateKey(); } void MXC_AES_SetKeySize(mxc_aes_keys_t key) { MXC_AES_RevB_SetKeySize((mxc_aes_revb_regs_t *)MXC_AES, (mxc_aes_revb_keys_t)key); } mxc_aes_keys_t MXC_AES_GetKeySize(void) { return MXC_AES_RevB_GetKeySize((mxc_aes_revb_regs_t *)MXC_AES); } void MXC_AES_FlushInputFIFO(void) { MXC_AES_RevB_FlushInputFIFO((mxc_aes_revb_regs_t *)MXC_AES); } void MXC_AES_FlushOutputFIFO(void) { MXC_AES_RevB_FlushOutputFIFO((mxc_aes_revb_regs_t *)MXC_AES); } void MXC_AES_Start(void) { MXC_AES_RevB_Start((mxc_aes_revb_regs_t *)MXC_AES); } uint32_t MXC_AES_GetFlags(void) { return MXC_AES_RevB_GetFlags((mxc_aes_revb_regs_t *)MXC_AES); } void MXC_AES_ClearFlags(uint32_t flags) { MXC_AES_RevB_ClearFlags((mxc_aes_revb_regs_t *)MXC_AES, flags); } int MXC_AES_Generic(mxc_aes_req_t *req) { return MXC_AES_RevB_Generic((mxc_aes_revb_regs_t *)MXC_AES, (mxc_aes_revb_req_t *)req); } int MXC_AES_Encrypt(mxc_aes_req_t *req) { return MXC_AES_RevB_Encrypt((mxc_aes_revb_regs_t *)MXC_AES, (mxc_aes_revb_req_t *)req); } int MXC_AES_Decrypt(mxc_aes_req_t *req) { return MXC_AES_RevB_Decrypt((mxc_aes_revb_regs_t *)MXC_AES, (mxc_aes_revb_req_t *)req); } int MXC_AES_TXDMAConfig(void *src_addr, int len) { return MXC_AES_RevB_TXDMAConfig(src_addr, len); } int MXC_AES_RXDMAConfig(void *dest_addr, int len) { return MXC_AES_RevB_RXDMAConfig(dest_addr, len); } int MXC_AES_GenericAsync(mxc_aes_req_t *req, uint8_t enc) { return MXC_AES_RevB_GenericAsync((mxc_aes_revb_regs_t *)MXC_AES, (mxc_aes_revb_req_t *)req, enc); } int MXC_AES_EncryptAsync(mxc_aes_req_t *req) { return MXC_AES_RevB_EncryptAsync((mxc_aes_revb_regs_t *)MXC_AES, (mxc_aes_revb_req_t *)req); } int MXC_AES_DecryptAsync(mxc_aes_req_t *req) { return MXC_AES_RevB_DecryptAsync((mxc_aes_revb_regs_t *)MXC_AES, (mxc_aes_revb_req_t *)req); } void MXC_AES_SetExtKey(const void *key, mxc_aes_keys_t len) { MXC_AES_RevB_SetExtKey((mxc_aeskeys_revb_regs_t *)MXC_AESKEYS, key, len); } int MXC_AES_SetPORKey(const void *key, mxc_aes_keys_t len) { int err = E_BAD_PARAM; uint8_t keyr[32]; // Make the key location readable/writable MXC_FLC_UnlockInfoBlock(KEY_ADDR); // Write the key switch (len) { case MXC_AES_128BITS: reverse_key(key, keyr, 16); err = MXC_FLC_Write(KEY_ADDR, 16, (uint32_t *)keyr); break; case MXC_AES_192BITS: reverse_key(key, keyr, 24); err = MXC_FLC_Write(KEY_ADDR, 24, (uint32_t *)keyr); break; case MXC_AES_256BITS: reverse_key(key, keyr, 32); err = MXC_FLC_Write(KEY_ADDR, 32, (uint32_t *)keyr); break; } if (err == E_NO_ERROR) { // Write the magic value to activate the key err = MXC_FLC_Write(FMV_ADDR, sizeof(fmv), (uint32_t *)fmv); // Lock the key region from reads/writes MXC_FLC_LockInfoBlock(KEY_ADDR); return err; } // Lock the key region from reads/writes MXC_FLC_LockInfoBlock(KEY_ADDR); return err; } int MXC_AES_ClearPORKey() { int err; // The first 40 bytes of the page contain the FMV and AES key, no // need to save those. uint8_t page[MXC_FLASH_PAGE_SIZE - 40]; // Make the key location readable/writable MXC_FLC_UnlockInfoBlock(FMV_ADDR); // Copy the current memory contents memcpy(page, (uint8_t *)FMV_ADDR + 40, MXC_FLASH_PAGE_SIZE - 40); err = MXC_FLC_PageErase(FMV_ADDR); if (err != E_NO_ERROR) { // Couldn't erase the memory. Abort. // Lock the key region from reads/writes MXC_FLC_LockInfoBlock(FMV_ADDR); return err; } // Write the old contents (minus the fmv and key) back to the part err = MXC_FLC_Write(FMV_ADDR + 40, MXC_FLASH_PAGE_SIZE - 40, (uint32_t *)page); // Lock the key region from reads/writes MXC_FLC_LockInfoBlock(FMV_ADDR); return err; } void MXC_AES_CopyPORKeyToKeyRegisters(mxc_aes_keys_t len) { // Make the key location readable/writable MXC_FLC_UnlockInfoBlock(KEY_ADDR); // Copy the values to the key register switch (len) { case MXC_AES_128BITS: memcpy(MXC_AESKEYS, (uint8_t *)KEY_ADDR, 16); break; case MXC_AES_192BITS: memcpy(MXC_AESKEYS, (uint8_t *)KEY_ADDR, 24); break; case MXC_AES_256BITS: memcpy(MXC_AESKEYS, (uint8_t *)KEY_ADDR, 32); break; } // Lock the key region from reads/writes MXC_FLC_LockInfoBlock(KEY_ADDR); } int MXC_AES_HasPORKey() { int res; // Make the key location readable/writable MXC_FLC_UnlockInfoBlock(FMV_ADDR); // Look for the magic value. res = memcmp((uint8_t *)FMV_ADDR, (uint8_t *)fmv, 8); // Lock the key region from reads/writes MXC_FLC_LockInfoBlock(FMV_ADDR); return !res; }