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add:crc8和16通用算法，crc32常用算法
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@allewalker
allewalker committed Mar 4, 2025
1 parent e4d0bfb commit 888e683
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Showing 3 changed files with 252 additions and 52 deletions.
220 changes: 220 additions & 0 deletions components/crypto/luat_crc.c
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Original file line number Diff line number Diff line change
@@ -0,0 +1,220 @@
#include "luat_crypto.h"
#include "luat_malloc.h"

uint8_t luat_crc8(const void *data, uint32_t len, uint8_t start, uint8_t poly, uint8_t is_reverse)
{
uint32_t i;
uint8_t CRC8 = start;
uint8_t wTemp = poly;
uint8_t *Src = (uint8_t *)data;
if (is_reverse)
{
poly = 0;
for (i = 0; i < 8; i++)
{
if (wTemp & (1 << (7 - i)))
{
poly |= 1 << i;
}
}
while (len--)
{

CRC8 ^= *Src++;
for (i = 0; i < 8; i++)
{
if ((CRC8 & 0x01))
{
CRC8 >>= 1;
CRC8 ^= poly;
}
else
{
CRC8 >>= 1;
}
}
}
}
else
{
while (len--)
{

CRC8 ^= *Src++;
for (i = 8; i > 0; --i)
{
if ((CRC8 & 0x80))
{
CRC8 <<= 1;
CRC8 ^= poly;
}
else
{
CRC8 <<= 1;
}
}
}
}
return CRC8;
}

/************************************************************************/
/* CRC16 */
/************************************************************************/
uint16_t luat_crc16(const void *data, uint32_t len, uint16_t start, uint16_t poly, uint8_t is_reverse)
{
uint32_t i;
uint16_t CRC16 = start;
uint16_t wTemp = poly;
uint8_t *Src = (uint8_t *)data;
if (is_reverse)
{
poly = 0;
for (i = 0; i < 16; i++)
{
if (wTemp & (1 << (15 - i)))
{
poly |= 1 << i;
}
}
while (len--)
{
for (i = 0; i < 8; i++)
{
if ((CRC16 & 0x0001) != 0)
{
CRC16 >>= 1;
CRC16 ^= poly;
}
else
{
CRC16 >>= 1;
}
if ((*Src&(1 << i)) != 0)
{
CRC16 ^= poly;
}
}
Src++;
}
}
else
{
while (len--)
{
for (i = 8; i > 0; i--)
{
if ((CRC16 & 0x8000) != 0)
{
CRC16 <<= 1;
CRC16 ^= poly;
}
else
{
CRC16 <<= 1;
}
if ((*Src&(1 << (i - 1))) != 0)
{
CRC16 ^= poly;
}
}
Src++;
}
}

return CRC16;
}


static uint32_t *luat_crc32_table;
static uint32_t luat_crc32_root;
/**
* @brief 反转数据
* @param ref 需要反转的变量
* @param ch 反转长度，多少位
* @retval N反转后的数据
*/
static unsigned long int prvReflect(unsigned long int ref, uint8_t ch)
{
unsigned long int value = 0;
unsigned long int i;
for (i = 1; i < (unsigned long int)(ch + 1); i++)
{
if (ref & 1)
value |= (unsigned long int)1 << (ch - i);
ref >>= 1;
}
return value;
}

/**
* @brief 建立CRC32的查询表
* @param Tab 表缓冲
* @param Gen CRC32根
* @retval None
*/
static void prvCRC32_CreateTable(uint32_t *Tab, uint32_t Gen)
{
uint32_t crc;
uint32_t i, j, temp, t1, t2, flag;
if (Tab[1] != 0)
return;
for (i = 0; i < 256; i++)
{
temp = prvReflect(i, 8);
Tab[i] = temp << 24;
for (j = 0; j < 8; j++)
{
flag = Tab[i] & 0x80000000;
t1 = Tab[i] << 1;
if (0 == flag)
{
t2 = 0;
}
else
{
t2 = Gen;
}
Tab[i] = t1 ^ t2;
}
crc = Tab[i];
Tab[i] = prvReflect(crc, 32);
}
}


/**
* @brief 计算buffer的crc校验码
* @param CRC32_Table CRC32表
* @param Buf 缓冲
* @param Size 缓冲区长度
* @param CRC32 初始CRC32值
* @retval 计算后的CRC32
*/
static uint32_t prvCRC32_Cal(uint32_t *CRC32_Table, const uint8_t *Buf, uint32_t Size, uint32_t CRC32Last)
{
uint32_t i;
for (i = 0; i < Size; i++)
{
CRC32Last = CRC32_Table[(CRC32Last ^ Buf[i]) & 0xff] ^ (CRC32Last >> 8);
}
return CRC32Last;
}

uint32_t luat_crc32(const void *data, uint32_t len, uint32_t start, uint32_t poly)
{
if (!poly)
{
poly = 0x04C11DB7;
}
if (poly != luat_crc32_root)
{
luat_crc32_root = poly;
if (!luat_crc32_table)
{
luat_crc32_table = luat_heap_malloc(1024);
}
prvCRC32_CreateTable(luat_crc32_table, luat_crc32_root);
}
return prvCRC32_Cal(luat_crc32_table, data, len, start);
}
31 changes: 31 additions & 0 deletions luat/include/luat_crypto.h
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Original file line number Diff line number Diff line change
Expand Up @@ -138,4 +138,35 @@ typedef struct luat_crypto_cipher_ctx

int luat_crypto_cipher_xxx(luat_crypto_cipher_ctx_t* cctx);

/**
* @brief crc8通用算法
* @param data 输入数据
* @param len 长度
* @param start 起始值，一般是0
* @param poly 多项式
* @param is_reverse 是否逆序计算，顺序从MSB算到LSB，逆序从LSB算到MSB，不清楚的2个都试试
* @return 输出值
*/
uint8_t luat_crc8(const void *data, uint32_t len, uint8_t start, uint8_t poly, uint8_t is_reverse);

/**
* @brief crc16通用算法
* @param data 输入数据
* @param len 长度
* @param start 起始值
* @param poly 多项式
* @param is_reverse 是否逆序计算，顺序从MSB算到LSB，逆序从LSB算到MSB，不清楚的2个都试试
* @return 输出值
*/
uint16_t luat_crc16(const void *data, uint32_t len, uint16_t start, uint16_t poly, uint8_t is_reverse);

/**
* @brief crc32常用算法
* @param data 输入数据
* @param len 长度
* @param start 起始值，一般是0xffffffff
* @param poly 多项式，一般是0x04C11DB7，填0会自动设置成0x04C11DB7
* @return 输出值
*/
uint32_t luat_crc32(const void *data, uint32_t len, uint32_t start, uint32_t poly);
#endif
53 changes: 1 addition & 52 deletions luat/modules/luat_lib_crypto.c
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Original file line number Diff line number Diff line change
Expand Up @@ -397,58 +397,7 @@ static int l_crypto_crc8(lua_State *L)
if (lua_isboolean(L, 4)) {
is_rev = lua_toboolean(L, 4);
}
uint8_t i;
uint8_t CRC8 = start;
uint8_t *Src = (uint8_t *)inputData;
if (is_rev)
{
poly = 0;
for (i = 0; i < 8; i++)
{
if (start & (1 << (7 - i)))
{
poly |= 1 << i;
}
}
while (len--)
{

CRC8 ^= *Src++;
for (i = 0; i < 8; i++)
{
if ((CRC8 & 0x01))
{
CRC8 >>= 1;
CRC8 ^= poly;
}
else
{
CRC8 >>= 1;
}
}
}
}
else
{
while (len--)
{

CRC8 ^= *Src++;
for (i = 8; i > 0; --i)
{
if ((CRC8 & 0x80))
{
CRC8 <<= 1;
CRC8 ^= poly;
}
else
{
CRC8 <<= 1;
}
}
}
}
lua_pushinteger(L, CRC8);
lua_pushinteger(L, luat_crc8(inputData, len, start, poly, is_rev));
}
return 1;
}
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