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DES和3DES加密算法C语言实现
记录DES和3DES加密算法最简洁易懂的C语言源码 主要是要用到CBC这部分的算法，后边也有一个工具可以提供验证，因为网上的工具含有CBC的很少，也方便大家吧#define MBEDTLS_DES_ENCRYPT 1 #define MBEDTLS_DES_DECRYPT 0 #define MBEDTLS_ERR_DES_INVALID_INPUT_LENGTH -0x0002 /**< The data input has an invalid length. */ #define MBEDTLS_DES_KEY_SIZE 8 #define DES_KEY_SIZE (8) #define DES3_KEY2_SIZE (16) #define DES3_KEY3_SIZE (24) typedef struct { uint32_t sk[32]; /*!< DES subkeys */ }des_context; /** * \brief Triple-DES context structure */ typedef struct { uint32_t sk[96]; /*!< 3DES subkeys */ }des3_context; #define DES_C #if defined(DES_C) #include "des.h" #include #include #if !defined(DES_ALT) /* Implementation that should never be optimized out by the compiler */ static void zeroize( void *v, size_t n ) { volatile unsigned char *p = (unsigned char*)v; while( n-- ) *p++ = 0; } /* * 32-bit integer manipulation macros (big endian) */ #ifndef GET_UINT32_BE #define GET_UINT32_BE(n,b,i) \ { \ (n) = ( (uint32_t) (b)[(i) ] << 24 ) \ | ( (uint32_t) (b)[(i) + 1] << 16 ) \ | ( (uint32_t) (b)[(i) + 2] << 8 ) \ | ( (uint32_t) (b)[(i) + 3] ); \ } #endif #ifndef PUT_UINT32_BE #define PUT_UINT32_BE(n,b,i) \ { \ (b)[(i) ] = (unsigned char) ( (n) >> 24 ); \ (b)[(i) + 1] = (unsigned char) ( (n) >> 16 ); \ (b)[(i) + 2] = (unsigned char) ( (n) >> 8 ); \ (b)[(i) + 3] = (unsigned char) ( (n) ); \ } #endif /* * Expanded DES S-boxes */ static const uint32_t SB1[64] = { 0x01010400, 0x00000000, 0x00010000, 0x01010404, 0x01010004, 0x00010404, 0x00000004, 0x00010000, 0x00000400, 0x01010400, 0x01010404, 0x00000400, 0x01000404, 0x01010004, 0x01000000, 0x00000004, 0x00000404, 0x01000400, 0x01000400, 0x00010400, 0x00010400, 0x01010000, 0x01010000, 0x01000404, 0x00010004, 0x01000004, 0x01000004, 0x00010004, 0x00000000, 0x00000404, 0x00010404, 0x01000000, 0x00010000, 0x01010404, 0x00000004, 0x01010000, 0x01010400, 0x01000000, 0x01000000, 0x00000400, 0x01010004, 0x00010000, 0x00010400, 0x01000004, 0x00000400, 0x00000004, 0x01000404, 0x00010404, 0x01010404, 0x00010004, 0x01010000, 0x01000404, 0x01000004, 0x00000404, 0x00010404, 0x01010400, 0x00000404, 0x01000400, 0x01000400, 0x00000000, 0x00010004, 0x00010400, 0x00000000, 0x01010004 }; static const uint32_t SB2[64] = { 0x80108020, 0x80008000, 0x00008000, 0x00108020, 0x00100000, 0x00000020, 0x80100020, 0x80008020, 0x80000020, 0x80108020, 0x80108000, 0x80000000, 0x80008000, 0x00100000, 0x00000020, 0x80100020, 0x00108000, 0x00100020, 0x80008020, 0x00000000, 0x80000000, 0x00008000, 0x00108020, 0x80100000, 0x00100020, 0x80000020, 0x00000000, 0x00108000, 0x00008020, 0x80108000, 0x80100000, 0x00008020, 0x00000000, 0x00108020, 0x80100020, 0x00100000, 0x80008020, 0x80100000, 0x80108000, 0x00008000, 0x80100000, 0x80008000, 0x00000020, 0x80108020, 0x00108020, 0x00000020, 0x00008000, 0x80000000, 0x00008020, 0x80108000, 0x00100000, 0x80000020, 0x00100020, 0x80008020, 0x80000020, 0x00100020, 0x00108000, 0x00000000, 0x80008000, 0x00008020, 0x80000000, 0x80100020, 0x80108020, 0x00108000 }; static const uint32_t SB3[64] = { 0x00000208, 0x08020200, 0x00000000, 0x08020008, 0x08000200, 0x00000000, 0x00020208, 0x08000200, 0x00020008, 0x08000008, 0x08000008, 0x00020000, 0x08020208, 0x00020008, 0x08020000, 0x00000208, 0x08000000, 0x00000008, 0x08020200, 0x00000200, 0x00020200, 0x08020000, 0x08020008, 0x00020208, 0x08000208, 0x00020200, 0x00020000, 0x08000208, 0x00000008, 0x08020208, 0x00000200, 0x08000000, 0x08020200, 0x08000000, 0x00020008, 0x00000208, 0x00020000, 0x08020200, 0x08000200, 0x00000000, 0x00000200, 0x00020008, 0x08020208, 0x08000200, 0x08000008,