aes.cpp

网络传输方面的范例程序,其中有MD5加密和解密的子程序,可以参考

#include "stdafx.h"
#include "aes.h"

static WORD digitValue[]=
{
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0x0000, 0x0001, 0x0002, 0x0003, 0x0004, 0x0005, 0x0006, 0x0007,
  0x0008, 0x0009, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0x000a, 0x000b, 0x000c, 0x000d, 0x000e, 0x000f, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0x000a, 0x000b, 0x000c, 0x000d, 0x000e, 0x000f, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff,
  0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff
};
static unsigned char nextKeyScheduleDword[] = 
{
     1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15, 16,
    17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32,
    33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43,  0
};
static  ULONG initialKeySchedule[] = 
{
    0xb7e15163, 0x5618cb1c,  /* Pseudo-round #0 */
    0xf45044d5, 0x9287be8e,  /* Round #1 */
    0x30bf3847, 0xcef6b200,  /* Round #2 */
    0x6d2e2bb9, 0x0b65a572,  /* Round #3 */
    0xa99d1f2b, 0x47d498e4,  /* Round #4 */
    0xe60c129d, 0x84438c56,  /* Round #5 */
    0x227b060f, 0xc0b27fc8,  /* Round #6 */
    0x5ee9f981, 0xfd21733a,  /* Round #7 */
    0x9b58ecf3, 0x399066ac,  /* Round #8 */
    0xd7c7e065, 0x75ff5a1e,  /* Round #9 */
    0x1436d3d7, 0xb26e4d90,  /* Round #10 */
    0x50a5c749, 0xeedd4102,  /* Round #11 */
    0x8d14babb, 0x2b4c3474,  /* Round #12 */
    0xc983ae2d, 0x67bb27e6,  /* Round #13 */
    0x05f2a19f, 0xa42a1b58,  /* Round #14 */
    0x42619511, 0xe0990eca,  /* Round #15 */
    0x7ed08883, 0x1d08023c,  /* Round #16 */
    0xbb3f7bf5, 0x5976f5ae,  /* Round #17 */
    0xf7ae6f67, 0x95e5e920,  /* Round #18 */
    0x341d62d9, 0xd254dc92,  /* Round #19 */
    0x708c564b, 0x0ec3d004,  /* Round #20 */
    0xacfb49bd, 0x4b32c376   /* Pseudo-round #21 */
};
CAES::CAES()
{
}
CAES::~CAES()
{
}
void CAES::Rc6ComputeKeySchedule(BYTE* key, int keyLengthInBytes,unsigned long* S)
{
  unsigned long L[(255+4-1)/4];
  unsigned int count;//int count;
  unsigned long i,j;
  unsigned long A,B;
  unsigned long thirtytwo = 32;

  UCHAR nextKeyDword[((255+4-1)/4)*4];

  /* Compute number of dwords taken up by key */
  unsigned long c = ((keyLengthInBytes+4-1) >> 2)
                   +((((unsigned long) keyLengthInBytes)-1) >> 31);


  /* Set up table of indices of next element in original key array.
   * We'll make use of the fact that Intels are little-endian. */
  *((unsigned long*) &(nextKeyDword[0])) = 0x04030201;
  *((unsigned long*) &(nextKeyDword[4])) = 0x08070605;

  count = 4;
  while ((count += 4) < c) {
    *((unsigned long*) &(nextKeyDword[count])) =
      (count*0x01010101UL)+0x04030201;
  }

  nextKeyDword[c-1] = 0;


  /* Zero out last element of array of key dwords */
  L[c-1] = 0;


  /* Load all the key bytes into the array of key dwords.  This method
   * of performing this task requires a little-endian CPU. */
  memcpy((void*) L, (void*) key, keyLengthInBytes);


  /* Initialize key schedule array */
  memcpy((void*) S, (void*) initialKeySchedule, 4*(2+2*ROUNDS+2));


  count = ((c <= (2+2*ROUNDS+2)) ? (2+2*ROUNDS+2) : c);
  A = B = i = j = 0;

  /* Mix the key into the key schedule array */
  do {
    unsigned long sum;

    S[i] += A+B;
    A = S[i] = CONST_ROTL(S[i], 3);
    i = nextKeyScheduleDword[i];

    sum = A+B;
    L[j] += sum;
    B = L[j] = ROTL(L[j], sum);
    j = nextKeyDword[j];


    S[i] += A+B;
    A = S[i] = CONST_ROTL(S[i], 3);
    i = nextKeyScheduleDword[i];

    sum = A+B;
    L[j] += sum;
    B = L[j] = ROTL(L[j], sum);
    j = nextKeyDword[j];


    S[i] += A+B;
    A = S[i] = CONST_ROTL(S[i], 3);
    i = nextKeyScheduleDword[i];

    sum = A+B;
    L[j] += sum;
    B = L[j] = ROTL(L[j], sum);
    j = nextKeyDword[j];
  } while (--count > 0);
}


/*
 * Rc6EncryptEcb() encrypts a specified number of blocks in ECB mode.
 */
void CAES::Rc6EncryptEcb(unsigned long* keySchedule, int numberOfBlocks,
                          unsigned long* plaintext, unsigned long* ciphertext)
{
  unsigned long thirtytwo = 32;
  unsigned long S[2+2*ROUNDS+2];


  if (numberOfBlocks == 0)
    return;


  /* Let's put our key schedule conveniently in this stack frame */
  memcpy((void*) S, (void*) keySchedule, 4*(2+2*ROUNDS+2));


  do {
    unsigned long A, B, C, D;
    unsigned long t,u;

    /* Perform pseudo-round #0 and round #1 */
    B = plaintext[1]+S[0];
    D = plaintext[3]+S[1];

    t = (B+B+1)*B;
    u = (D+D+1)*D;
    t = CONST_ROTL(t, 5);
    u = CONST_ROTL(u, 5);

    A = plaintext[0] ^ t;
    A = ROTL(A, u)+S[2];
    C = plaintext[2] ^ u;
    C = ROTL(C, t)+S[3];


    /* Perform rounds #2-18 */
    ENCRYPT_MIDDLE(S, A, B, C, D);


    /* Perform round #19 */
    ENCRYPT_ROUND(S, 38, C, D, A, B,t,u);


    /* Perform round #20 and pseudo-round #21 */
    t = (A+A+1)*A;
    u = (C+C+1)*C;
    t = CONST_ROTL(t, 5);
    u = CONST_ROTL(u, 5);

    D ^= t;
    ciphertext[0] = A+S[42];
    ciphertext[3] = ROTL(D, u)+S[40];
    B ^= u;
    ciphertext[2] = C+S[43];
    ciphertext[1] = ROTL(B, t)+S[41];


    /* Update text pointers */
    plaintext += 4;
    ciphertext += 4;

  } while (--numberOfBlocks > 0);
}



/*
 * Rc6EncryptCbc() encrypts a specified number of blocks in CBC mode.
 * In the process, it alters the 16-byte value pointed to by ivBytes.
 */
void CAES::Rc6EncryptCbc(unsigned long* keySchedule, int numberOfBlocks,
                          unsigned long* ivDwords,
                          unsigned long* plaintext, unsigned long* ciphertext)
{
  unsigned long thirtytwo = 32;
  unsigned long IV[4];
  unsigned long S[2+2*ROUNDS+2];


  if (numberOfBlocks == 0)
    return;


  /* Let's put our IV and key schedule conveniently in this stack frame */
  IV[0] = ivDwords[0];
  IV[1] = ivDwords[1];
  IV[2] = ivDwords[2];
  IV[3] = ivDwords[3];
  memcpy((void*) S, (void*) keySchedule, 4*(2+2*ROUNDS+2));


  do 
  {
    unsigned long A, B, C, D;
    unsigned long t,u;

    /* XOR in IV and perform pseudo-round #0 and round #1 */
    B = (plaintext[1] ^ IV[1])+S[0];
    D = (plaintext[3] ^ IV[3])+S[1];

    t = (B+B+1)*B;
    u = (D+D+1)*D;
    t = CONST_ROTL(t, 5);
    u = CONST_ROTL(u, 5);

    A = (plaintext[0] ^ IV[0]) ^ t;
    A = ROTL(A, u)+S[2];
    C = (plaintext[2] ^ IV[2]) ^ u;
    C = ROTL(C, t)+S[3];


    /* Perform rounds #2-18 */
    ENCRYPT_MIDDLE(S, A, B, C, D);


    /* Perform round #19 */
    ENCRYPT_ROUND(S, 38, C, D, A, B,t,u);


    /* Perform round #20 and pseudo-round #17 and save IV */
    t = (A+A+1)*A;
    u = (C+C+1)*C;
    t = CONST_ROTL(t, 5);
    u = CONST_ROTL(u, 5);

    D ^= t;
    IV[0] = ciphertext[0] = A+S[42];
    IV[3] = ciphertext[3] = ROTL(D, u)+S[40];
    B ^= u;
    IV[2] = ciphertext[2] = C+S[43];
    IV[1] = ciphertext[1] = ROTL(B, t)+S[41];


    /* Update text pointers */
    plaintext += 4;
    ciphertext += 4;

  } while (--numberOfBlocks > 0);

  /* Save IV for next call */
  ivDwords[0] = IV[0];
  ivDwords[1] = IV[1];
  ivDwords[2] = IV[2];
  ivDwords[3] = IV[3];
}