dcp.cpp

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// T4 DCP  AES SHA CRC32
//  tests on channel 0  non-blocking  no context switching
 
#include <Arduino.h> // noInterrupts(), interrupts()
 
#include "utils/dcp.h"
 
using namespace std;
 
namespace utils {
 
// InputOutput  or just Input
#define __IO volatile
#define __I volatile
#define DCP_CH0SEMA_VALUE_MASK (0xFF0000U)
#define DCP_CH0STAT_ERROR_CODE_MASK (0xFF0000U)
#define DCP_HASH_BLOCK_SIZE 128
#define DCP_STAT_OTP_KEY_READY_MASK (0x10000000U)
#define DCP_KEY_INDEX_MASK (0x30U)
#define DCP_KEY_INDEX_SHIFT (4U)
#define DCP_KEY_INDEX(x) (((uint32_t)(((uint32_t)(x)) << DCP_KEY_INDEX_SHIFT)) & DCP_KEY_INDEX_MASK)
 
enum _generic_status {
  kStatus_Success = 0,
  kStatus_Fail = 1,
  kStatus_ReadOnly = 2,
  kStatus_OutOfRange = 3,
  kStatus_InvalidArgument = 4,
  kStatus_Timeout = 5,
  kStatus_DCP_Again = 6,
};
 
typedef enum _dcp_ch_enable {
  kDCP_chDisable = 0U,    
  kDCP_ch0Enable = 1U,    
  kDCP_ch1Enable = 2U,    
  kDCP_ch2Enable = 4U,    
  kDCP_ch3Enable = 8U,    
  kDCP_chEnableAll = 15U, 
} _dcp_ch_enable_t;
 
typedef enum _dcp_channel {
  kDCP_Channel0 = (1u << 16), 
  kDCP_Channel1 = (1u << 17), 
  kDCP_Channel2 = (1u << 18), 
  kDCP_Channel3 = (1u << 19), 
} dcp_channel_t;
 
typedef enum _dcp_key_slot {
  kDCP_KeySlot0 = 0U,     
  kDCP_KeySlot1 = 1U,     
  kDCP_KeySlot2 = 2U,     
  kDCP_KeySlot3 = 3U,     
  kDCP_OtpKey = 4U,       
  kDCP_OtpUniqueKey = 5U, 
  kDCP_PayloadKey = 6U,   
} dcp_key_slot_t;
 
typedef enum _dcp_swap {
  kDCP_NoSwap = 0x0U,
  kDCP_KeyByteSwap = 0x40000U,
  kDCP_KeyWordSwap = 0x80000U,
  kDCP_InputByteSwap = 0x100000U,
  kDCP_InputWordSwap = 0x200000U,
  kDCP_OutputByteSwap = 0x400000U,
  kDCP_OutputWordSwap = 0x800000U,
} dcp_swap_t;
 
typedef enum _dcp_hash_algo_t {
  kDCP_Sha1,   
  kDCP_Sha256, 
  kDCP_Crc32,  
} dcp_hash_algo_t;
 
enum _dcp_hash_digest_len {
  kDCP_OutLenSha1 = 20u,
  kDCP_OutLenSha256 = 32u,
  kDCP_OutLenCrc32 = 4u,
};
 
enum _dcp_work_packet_bit_definitions {
  kDCP_CONTROL0_DECR_SEMAPHOR = 1u << 1, /* DECR_SEMAPHOR */
  kDCP_CONTROL0_ENABLE_HASH = 1u << 6,   /* ENABLE_HASH */
  kDCP_CONTROL0_HASH_INIT = 1u << 12,    /* HASH_INIT */
  kDCP_CONTROL0_HASH_TERM = 1u << 13,    /* HASH_TERM */
  kDCP_CONTROL1_HASH_SELECT_SHA256 = 2u << 16,
  kDCP_CONTROL1_HASH_SELECT_SHA1 = 0u << 16,
  kDCP_CONTROL1_HASH_SELECT_CRC32 = 1u << 16,
};
 
typedef struct _dcp_hash_ctx_t {
  uint32_t x[58];
} dcp_hash_ctx_t;
 
typedef union _dcp_hash_block {
  uint32_t w[DCP_HASH_BLOCK_SIZE / 4]; 
  uint8_t b[DCP_HASH_BLOCK_SIZE];      
} dcp_hash_block_t;
 
typedef enum _dcp_hash_algo_state {
  kDCP_StateHashInit = 1u, 
  kDCP_StateHashUpdate,    
} dcp_hash_algo_state_t;
 
typedef struct _dcp_handle {
  dcp_channel_t channel; 
  dcp_key_slot_t
      keySlot; 
  uint32_t swapConfig; 
  uint32_t keyWord[4];
  uint32_t iv[4];
} dcp_handle_t;
 
typedef struct _dcp_hash_ctx_internal {
  dcp_hash_block_t blk;        
  size_t blksz;                
  dcp_hash_algo_t algo;        
  dcp_hash_algo_state_t state; 
  uint32_t fullMessageSize;    
  uint32_t ctrl0;              
  uint32_t runningHash[9];     
  dcp_handle_t *handle;
} dcp_hash_ctx_internal_t;
 
typedef struct _dcp_work_packet {
  uint32_t nextCmdAddress;
  uint32_t control0;
  uint32_t control1;
  uint32_t sourceBufferAddress;
  uint32_t destinationBufferAddress;
  uint32_t bufferSize;
  uint32_t payloadPointer;
  uint32_t status;
} dcp_work_packet_t;
 
typedef struct {
  __IO uint32_t CTRL; 
  uint8_t RESERVED_0[12];
  __IO uint32_t STAT; 
  uint8_t RESERVED_1[12];
  __IO uint32_t CHANNELCTRL; 
  uint8_t RESERVED_2[12];
  __IO uint32_t CAPABILITY0; 
  uint8_t RESERVED_3[12];
  __I uint32_t CAPABILITY1; 
  uint8_t RESERVED_4[12];
  __IO uint32_t CONTEXT; 
  uint8_t RESERVED_5[12];
  __IO uint32_t KEY; 
  uint8_t RESERVED_6[12];
  __IO uint32_t KEYDATA; 
  uint8_t RESERVED_7[12];
  __I uint32_t PACKET0; 
  uint8_t RESERVED_8[12];
  __I uint32_t PACKET1; 
  uint8_t RESERVED_9[12];
  __I uint32_t PACKET2; 
  uint8_t RESERVED_10[12];
  __I uint32_t PACKET3; 
  uint8_t RESERVED_11[12];
  __I uint32_t PACKET4; 
  uint8_t RESERVED_12[12];
  __I uint32_t PACKET5; 
  uint8_t RESERVED_13[12];
  __I uint32_t PACKET6; 
  uint8_t RESERVED_14[28];
  __IO uint32_t CH0CMDPTR; 
  uint8_t RESERVED_15[12];
  __IO uint32_t CH0SEMA; 
  uint8_t RESERVED_16[12];
  __IO uint32_t CH0STAT; 
  uint8_t RESERVED_17[12];
  __IO uint32_t CH0OPTS; 
  uint8_t RESERVED_18[12];
  __IO uint32_t CH1CMDPTR; 
  uint8_t RESERVED_19[12];
  __IO uint32_t CH1SEMA; 
  uint8_t RESERVED_20[12];
  __IO uint32_t CH1STAT; 
  uint8_t RESERVED_21[12];
  __IO uint32_t CH1OPTS; 
  uint8_t RESERVED_22[12];
  __IO uint32_t CH2CMDPTR; 
  uint8_t RESERVED_23[12];
  __IO uint32_t CH2SEMA; 
  uint8_t RESERVED_24[12];
  __IO uint32_t CH2STAT; 
  uint8_t RESERVED_25[12];
  __IO uint32_t CH2OPTS; 
  uint8_t RESERVED_26[12];
  __IO uint32_t CH3CMDPTR; 
  uint8_t RESERVED_27[12];
  __IO uint32_t CH3SEMA; 
  uint8_t RESERVED_28[12];
  __IO uint32_t CH3STAT; 
  uint8_t RESERVED_29[12];
  __IO uint32_t CH3OPTS; 
  uint8_t RESERVED_30[524];
  __IO uint32_t DBGSELECT; 
  uint8_t RESERVED_31[12];
  __I uint32_t DBGDATA; 
  uint8_t RESERVED_32[12];
  __IO uint32_t PAGETABLE; 
  uint8_t RESERVED_33[12];
  __I uint32_t VERSION; 
} DCP_Type;
 
#define DCP ((DCP_Type *)0x402FC000)
 
FLASHMEM static void dcp_reverse_and_copy(uint8_t *src, uint8_t *dest, size_t src_len) {
  for (unsigned int i = 0; i < src_len; i++) {
    dest[i] = src[src_len - 1 - i];
  }
}
 
FLASHMEM static uint32_t dcp_get_channel_status(dcp_channel_t channel) {
  uint32_t statReg = 0;
  uint32_t semaReg = 0;
  uint32_t status = kStatus_Fail;
 
  switch (channel) {
  case kDCP_Channel0:
    statReg = DCP->CH0STAT;
    semaReg = DCP->CH0SEMA;
    break;
 
  case kDCP_Channel1:
    statReg = DCP->CH1STAT;
    semaReg = DCP->CH1SEMA;
    break;
 
  case kDCP_Channel2:
    statReg = DCP->CH2STAT;
    semaReg = DCP->CH2SEMA;
    break;
 
  case kDCP_Channel3:
    statReg = DCP->CH3STAT;
    semaReg = DCP->CH3SEMA;
    break;
 
  default:
    break;
  }
 
  if (!((semaReg & DCP_CH0SEMA_VALUE_MASK) || (statReg & DCP_CH0STAT_ERROR_CODE_MASK))) {
    status = kStatus_Success;
  }
 
  return status;
}
 
FLASHMEM static void dcp_clear_status() {
  volatile uint32_t *dcpStatClrPtr = &DCP->STAT + 2u;
  *dcpStatClrPtr = 0xFFu;
}
 
FLASHMEM static void dcp_clear_channel_status(uint32_t mask) {
  volatile uint32_t *chStatClrPtr;
 
  if (mask & kDCP_Channel0) {
    chStatClrPtr = &DCP->CH0STAT + 2u;
    *chStatClrPtr = 0xFFu;
  }
  if (mask & kDCP_Channel1) {
    chStatClrPtr = &DCP->CH1STAT + 2u;
    *chStatClrPtr = 0xFFu;
  }
  if (mask & kDCP_Channel2) {
    chStatClrPtr = &DCP->CH2STAT + 2u;
    *chStatClrPtr = 0xFFu;
  }
  if (mask & kDCP_Channel3) {
    chStatClrPtr = &DCP->CH3STAT + 2u;
    *chStatClrPtr = 0xFFu;
  }
}
 
uint32_t DCP_WaitForChannelComplete(dcp_handle_t *handle) {
  /* wait if our channel is still active */
  while ((DCP->STAT & (uint32_t)handle->channel) == handle->channel) {
  }
 
  if (dcp_get_channel_status(handle->channel) != kStatus_Success) {
    dcp_clear_status();
    dcp_clear_channel_status(handle->channel);
    return kStatus_Fail;
  }
 
  return kStatus_Success;
}
 
FLASHMEM static uint32_t dcp_schedule_work(dcp_handle_t *handle, dcp_work_packet_t *dcpPacket) {
  uint32_t status;
 
  /* check if our channel is active */
  if ((DCP->STAT & (uint32_t)handle->channel) != handle->channel) {
    noInterrupts();
 
    /* re-check if our channel is still available */
    if ((DCP->STAT & (uint32_t)handle->channel) == 0) {
      volatile uint32_t *cmdptr = NULL;
      volatile uint32_t *chsema = NULL;
 
      switch (handle->channel) {
      case kDCP_Channel0:
        cmdptr = &DCP->CH0CMDPTR;
        chsema = &DCP->CH0SEMA;
        break;
 
      case kDCP_Channel1:
        cmdptr = &DCP->CH1CMDPTR;
        chsema = &DCP->CH1SEMA;
        break;
 
      case kDCP_Channel2:
        cmdptr = &DCP->CH2CMDPTR;
        chsema = &DCP->CH2SEMA;
        break;
 
      case kDCP_Channel3:
        cmdptr = &DCP->CH3CMDPTR;
        chsema = &DCP->CH3SEMA;
        break;
 
      default:
        break;
      }
 
      if (cmdptr && chsema) {
        /* set out packet to DCP CMDPTR */
        *cmdptr = (uint32_t)dcpPacket;
 
        /* set the channel semaphore */
        *chsema = 1u;
      }
      status = kStatus_Success;
    }
 
    else {
      status = kStatus_DCP_Again;
    }
    interrupts();
  }
 
  else {
    return kStatus_DCP_Again;
  }
 
  return status;
}
 
FLASHMEM static uint32_t dcp_hash_update_non_blocking(dcp_hash_ctx_internal_t *ctxInternal,
                                                      dcp_work_packet_t *dcpPacket, const uint8_t *msg,
                                                      size_t size) {
  dcpPacket->control0 = ctxInternal->ctrl0 | (ctxInternal->handle->swapConfig & 0xFC0000u) |
                        kDCP_CONTROL0_ENABLE_HASH | kDCP_CONTROL0_DECR_SEMAPHOR;
  if (ctxInternal->algo == kDCP_Sha256) {
    dcpPacket->control1 = kDCP_CONTROL1_HASH_SELECT_SHA256;
  } else if (ctxInternal->algo == kDCP_Sha1) {
    dcpPacket->control1 = kDCP_CONTROL1_HASH_SELECT_SHA1;
  } else if (ctxInternal->algo == kDCP_Crc32) {
    dcpPacket->control1 = kDCP_CONTROL1_HASH_SELECT_CRC32;
  } else {
    return 1;
  }
  dcpPacket->sourceBufferAddress = (uint32_t)msg;
  dcpPacket->destinationBufferAddress = 0;
  dcpPacket->bufferSize = size;
  dcpPacket->payloadPointer = (uint32_t)ctxInternal->runningHash;
 
  return dcp_schedule_work(ctxInternal->handle, dcpPacket);
}
 
void dcp_hash_update(dcp_hash_ctx_internal_t *ctxInternal, const uint8_t *msg, size_t size) {
  uint32_t completionStatus;
  dcp_work_packet_t dcpWork = {0};
 
  do {
    completionStatus = dcp_hash_update_non_blocking(ctxInternal, &dcpWork, msg, size);
  } while (completionStatus == kStatus_DCP_Again);
 
  completionStatus = DCP_WaitForChannelComplete(ctxInternal->handle);
 
  ctxInternal->ctrl0 = 0; /* clear kDCP_CONTROL0_HASH_INIT and kDCP_CONTROL0_HASH_TERM flags */
  return;                 // (completionStatus);
}
 
FLASHMEM void dcp_hash_process_message_data(dcp_hash_ctx_internal_t *ctxInternal, const uint8_t *message,
                                            size_t messageSize) {
  /* if there is partially filled internal buffer, fill it to full block */
  if (ctxInternal->blksz > 0) {
    size_t toCopy = DCP_HASH_BLOCK_SIZE - ctxInternal->blksz;
    memcpy(&ctxInternal->blk.b[ctxInternal->blksz], message, toCopy);
    message += toCopy;
    messageSize -= toCopy;
 
    /* process full internal block */
    dcp_hash_update(ctxInternal, &ctxInternal->blk.b[0], DCP_HASH_BLOCK_SIZE);
  }
 
  /* process all full blocks in message[] */
  uint32_t fullBlocksSize = ((messageSize >> 6) << 6); /* (X / 64) * 64 */
  if (fullBlocksSize > 0) {
    dcp_hash_update(ctxInternal, message, fullBlocksSize);
    message += fullBlocksSize;
    messageSize -= fullBlocksSize;
  }
 
  /* copy last incomplete message bytes into internal block */
  memcpy(&ctxInternal->blk.b[0], message, messageSize);
  ctxInternal->blksz = messageSize;
}
 
FLASHMEM void DCP_HASH_Init(dcp_handle_t *handle, dcp_hash_ctx_t *ctx, dcp_hash_algo_t algo) {
  dcp_hash_ctx_internal_t *ctxInternal;
  ctxInternal = (dcp_hash_ctx_internal_t *)ctx;
  ctxInternal->algo = algo;
  ctxInternal->blksz = 0u;
  for (unsigned int i = 0; i < sizeof(ctxInternal->blk.w) / sizeof(ctxInternal->blk.w[0]); i++) {
    ctxInternal->blk.w[i] = 0u; // bug was 0
  }
  ctxInternal->state = kDCP_StateHashInit;
  ctxInternal->fullMessageSize = 0;
  ctxInternal->handle = handle;
}
 
FLASHMEM void DCP_HASH_Update(dcp_hash_ctx_t *ctx, const uint8_t *input, size_t inputSize) {
  bool isUpdateState;
  dcp_hash_ctx_internal_t *ctxInternal;
  size_t blockSize = DCP_HASH_BLOCK_SIZE;
 
  ctxInternal = (dcp_hash_ctx_internal_t *)ctx;
  ctxInternal->fullMessageSize += inputSize;
  /* if we are still less than DCP_HASH_BLOCK_SIZE bytes, keep only in context */
  if ((ctxInternal->blksz + inputSize) <= blockSize) {
    memcpy((&ctxInternal->blk.b[0]) + ctxInternal->blksz, input, inputSize);
    ctxInternal->blksz += inputSize;
    return;
  } else {
    isUpdateState = ctxInternal->state == kDCP_StateHashUpdate;
    if (!isUpdateState) {
      /* start NEW hash */
      ctxInternal->ctrl0 = kDCP_CONTROL0_HASH_INIT;
      ctxInternal->state = kDCP_StateHashUpdate;
    } else {
      //      dcp_hash_restore_running_hash(ctxInternal);  // context switch
    }
  }
 
  /* process input data */
  dcp_hash_process_message_data(ctxInternal, input, inputSize);
  //  dcp_hash_save_running_hash(ctxInternal);  // context
}
 
FLASHMEM void DCP_HASH_Finish(dcp_hash_ctx_t *ctx, uint8_t *output) {
  size_t algOutSize = 0;
  dcp_hash_ctx_internal_t *ctxInternal;
 
  ctxInternal = (dcp_hash_ctx_internal_t *)ctx;
 
  if (ctxInternal->state == kDCP_StateHashInit) {
    ctxInternal->ctrl0 = kDCP_CONTROL0_HASH_INIT; // dcp_hash_engine_init( ctxInternal);
 
  } else {
    // dcp_hash_restore_running_hash(ctxInternal);  // context
  }
 
  size_t outSize = 0u;
 
  /* compute algorithm output length */
  switch (ctxInternal->algo) {
  case kDCP_Sha256:
    outSize = kDCP_OutLenSha256;
    break;
  case kDCP_Sha1:
    outSize = kDCP_OutLenSha1;
    break;
  case kDCP_Crc32:
    outSize = kDCP_OutLenCrc32;
    break;
  default:
    break;
  }
  algOutSize = outSize;
 
  /* flush message last incomplete block, if there is any, and add padding bits */
  // dcp_hash_finalize( ctxInternal);
  ctxInternal->ctrl0 |= kDCP_CONTROL0_HASH_TERM;
  dcp_hash_update(ctxInternal, &ctxInternal->blk.b[0], ctxInternal->blksz);
 
  /* Reverse and copy result to output[] */
  dcp_reverse_and_copy((uint8_t *)ctxInternal->runningHash, &output[0], algOutSize);
 
  memset(ctx, 0, sizeof(dcp_hash_ctx_t));
}
 
FLASHMEM void dcp_init() {
  // volatile uint32_t *p;
  CCM_CCGR0 |= CCM_CCGR0_DCP(CCM_CCGR_ON); // DCP on
 
  DCP->CTRL = 0xF0800000u; /* reset value */
  DCP->CTRL = 0x30800000u; /* default value */
 
  dcp_clear_status();
  // clear channel status
  dcp_clear_channel_status(kDCP_Channel0 | kDCP_Channel1 | kDCP_Channel2 | kDCP_Channel3);
 
  DCP->CTRL = 0x00C00000; // enable caching  writes
  DCP->CHANNELCTRL = kDCP_ch0Enable;
}
 
FLASHMEM void prhash(unsigned char *h, int n) {
  int i;
 
  for (i = 0; i < n; i++) {
    Serial.printf("%02x", h[i]);
    if (i % 4 == 3)
      Serial.printf(" ");
  }
  Serial.printf("\n");
}
 
FLASHMEM void demo_sha256() {
  dcp_handle_t m_handle;
  dcp_hash_ctx_t hashCtx;
  uint8_t msg[16 * 1024], hash[32];         // msg is actually big kind-of-random
  static const uint8_t message[] = "hello"; // hash 2cf24dba ...
 
  m_handle.channel = kDCP_Channel0;
  m_handle.keySlot = kDCP_KeySlot0;
  m_handle.swapConfig = kDCP_NoSwap;
 
  DCP_HASH_Init(&m_handle, &hashCtx, kDCP_Sha256);
  DCP_HASH_Update(&hashCtx, message, 5);
  DCP_HASH_Finish(&hashCtx, hash);
  prhash(hash, 32);
 
  uint32_t t = micros();
  DCP_HASH_Init(&m_handle, &hashCtx, kDCP_Sha256);
  DCP_HASH_Update(&hashCtx, msg, sizeof(msg));
  DCP_HASH_Finish(&hashCtx, hash);
  t = micros() - t;
  Serial.printf("SHA256 %d bytes %d us  %.3f MBs\n", sizeof(msg), t, (float)sizeof(msg) / t);
  prhash(hash, 32);
}
 
FLASHMEM void demo_crc32() {
  dcp_handle_t m_handle;
  dcp_hash_ctx_t hashCtx;
  uint8_t msg[16 * 1024], hash[4];
  static const uint8_t message[] = "abcdbcdecdefdefgefghfghighijhijk";
  static const unsigned char crc32[] = {0x7f, 0x04, 0x6a, 0xdd}; // crc
 
  m_handle.channel = kDCP_Channel0;
  m_handle.keySlot = kDCP_KeySlot0;
  m_handle.swapConfig = kDCP_NoSwap;
 
  DCP_HASH_Init(&m_handle, &hashCtx, kDCP_Crc32);
  DCP_HASH_Update(&hashCtx, message, sizeof(message) - 1);
  DCP_HASH_Finish(&hashCtx, hash);
  Serial.printf("memcmp %d\n", memcmp(hash, crc32, 4));
  prhash(hash, 4);
 
  uint32_t t = micros();
  DCP_HASH_Init(&m_handle, &hashCtx, kDCP_Crc32);
  DCP_HASH_Update(&hashCtx, msg, sizeof(msg));
  DCP_HASH_Finish(&hashCtx, hash);
  t = micros() - t;
  Serial.printf("CRC32 %d bytes %d us  %.3f MBs\n", sizeof(msg), t, (float)sizeof(msg) / t);
  prhash(hash, 4);
}
 
FLASHMEM void hash(const uint8_t *msg, size_t msg_len, uint8_t *out_hash, dcp_hash_algo_t algo) {
  dcp_init();
 
  dcp_handle_t m_handle;
  dcp_hash_ctx_t hashCtx;
 
  m_handle.channel = kDCP_Channel0;
  m_handle.keySlot = kDCP_KeySlot0;
  m_handle.swapConfig = kDCP_NoSwap;
 
  DCP_HASH_Init(&m_handle, &hashCtx, algo);
  DCP_HASH_Update(&hashCtx, msg, msg_len);
  DCP_HASH_Finish(&hashCtx, out_hash);
}
 
FLASHMEM void hash_sha256(const uint8_t *msg, size_t msg_len, uint8_t *out_hash) {
  hash(msg, msg_len, out_hash, kDCP_Sha256);
}
 
FLASHMEM void hash_sha1(const uint8_t *msg, size_t msg_len, uint8_t *out_hash) {
  hash(msg, msg_len, out_hash, kDCP_Sha1);
}
 
} // namespace utils