tdes.cpp

伯克利做的SFTP安全文件传输协议

// tdes.cc
// test DES functions
// copyright SafeTP Development Group, Inc., 2000  Terms of use are as specified in license.txt

#include "des.h"         // TripleDES_{Encryption,Decryption}
#include "modes.h"       // CBC{Encryption,Decryption}
#include "datablok.h"    // DataBlock
#include <ctype.h>       // isprint
#include <string.h>      // memcpy
#include <stdio.h>       // printf
#include <iostream.h>    // cout

// simple util
void printBlock(byte const *data, int len, char const *label = NULL)
{
  DataBlock db(data, len);
  db.print(label);
}


// test a single encryption and decryption
bool testEncDec(BlockTransformation &enc, BlockTransformation &dec)
{
  byte const *data = (byte const*)"MS Sucks";
    // 8 (block size) bytes of data

  byte output[8];
    // output buffer

  // encrypt
  enc.ProcessBlock(data /*in*/, output /*out*/);

  printBlock(output, 8, "ciphertext");

  // decrypt
  dec.ProcessBlock(output /*in, out*/);

  // compare
  printBlock(output, 8, "output");
  bool ret = 0==memcmp(data, output, 8);
  if (ret) {
    printf("(success)\n");
  }
  else {
    printf("(failure)\n");
  }

  printf("\n");
  return ret;
}


bool test(bool fail)
{
  byte const *key = (byte const*)"abcdefghijklmnopqrstuvwx";
    // 24 bytes - 192 raw bits, of which only 168 will be used
    // (I don't set or check the unused, e.g. as parity)

  // test TripleDES in ECB mode
  TripleDES_Encryption enc(key+fail);
  TripleDES_Decryption dec(key);
  testEncDec(enc, dec);

  // test Triple-DES in CBC mode
  byte const *IV = (byte const*)"ivector!";
    // 8 byte initialization vector

  CBCEncryption enc2(enc, IV);
  CBCDecryption dec2(dec, IV);

  bool ok = true;
  ok &= testEncDec(enc2, dec2);
  ok &= testEncDec(enc2, dec2);     // ciphertext should be different
  return ok;
}


bool doit()
{
  bool ok = true;

  printf("------ should succeed --------\n");
  ok &= test(false /*fail*/);

  printf("------ should fail ---------\n");
  ok &= !test(true /*fail*/);

  return ok;
}


int main()
{
  try {
    if (doit()) {
      cout << "all tests succeeded\n";
      return 0;
    }
    else {
      cout << "at least one test failed\n";
      return 2;
    }
  }
  catch (xBase &x) {
    cout << "exception caught: " << x << endl;
    return 4;
  }
}