Example of use of symmetric encryption algorithm des common functions in OpenSSL

The main consists of 3 files:

1. Cryptotest.h:

#ifndef _cryptotest_h_#define _cryptotest_h_#include <string>using namespace std;typedef enum {general = 0,ECB, Cbc,cfb,ofb,triple_ecb,triple_cbc}crypto_mode;string des_encrypt (const string cleartext, const string key, Crypto_ mode mode); string des_decrypt (const string ciphertext, const string key, Crypto_mode mode); #endif//_cryptotest_h_

2. Destest.cpp:

#include <iostream> #include <string> #include <vector> #include <openssl/des.h> #include " Cryptotest.h "using namespace std;static unsigned char cbc_iv[8] = {' 0 ', ' 1 ', ' A ', ' B ', ' A ', ' B ', ' 9 ', ' 8 '};string des_encr Ypt (const string cleartext, const string key, Crypto_mode MODE) {string Strciphertext;switch (mode) {case General:case ECB: {Des_cblock Keyencrypt;memset (keyencrypt, 0, 8); if (Key.length () <= 8) memcpy (Keyencrypt, Key.c_str (), Key.length ()) ; Else memcpy (Keyencrypt, Key.c_str (), 8);D Es_key_schedule keyschedule;des_set_key_unchecked (&keyencrypt, & Keyschedule); Const_des_cblock inputtext;des_cblock outputtext;vector<unsigned char> vecCiphertext;unsigned char tmp[8];for (int i = 0; i < cleartext.length ()/8; i + +) {memcpy (Inputtext, cleartext.c_str () + i * 8, 8);D es_ecb_  Encrypt (&inputtext, &outputtext, &keyschedule, Des_encrypt); memcpy (TMP, Outputtext, 8); for (int j = 0; J < 8; J + +) Vecciphertext.push_back (Tmp[j]);} if (CLEARTEXT.LEngth ()% 8! = 0) {int tmp1 = Cleartext.length ()/8 * 8;int TMP2 = cleartext.length ()-Tmp1;memset (inputtext, 0, 8); MEMC PY (Inputtext, cleartext.c_str () + TMP1, TMP2);D es_ecb_encrypt (&inputtext, &outputtext, &keyschedule, DES_ ENCRYPT); memcpy (TMP, Outputtext, 8); for (int j = 0; J < 8; j + +) Vecciphertext.push_back (Tmp[j]);} Strciphertext.clear (); Strciphertext.assign (Vecciphertext.begin (), Vecciphertext.end ());} Break;case Cbc:{des_cblock Keyencrypt, Ivec;memset (keyencrypt, 0, 8); if (Key.length () <= 8) memcpy (Keyencrypt, key.c_ STR (), key.length ()); else memcpy (Keyencrypt, Key.c_str (), 8);D Es_key_schedule keyschedule;des_set_key_unchecked ( &keyencrypt, &keyschedule); memcpy (Ivec, Cbc_iv, sizeof (CBC_IV)); int ilength = Cleartext.length ()% 8? (Cleartext.length ()/8 + 1) * 8:cleartext.length (); unsigned char* tmp = new unsigned char[ilength + 16];memset (tmp, 0, Ilength);D es_ncbc_encrypt ((const unsigned char*) CLEARTEXT.C_STR (), TMP, Cleartext.length () +1, &keyschedulE, &ivec, des_encrypt); strciphertext = (char*) tmp;delete [] tmp;} Break;case Cfb:{des_cblock Keyencrypt, Ivec;memset (keyencrypt, 0, 8); if (Key.length () <= 8) memcpy (Keyencrypt, key.c_ STR (), key.length ()); else memcpy (Keyencrypt, Key.c_str (), 8);D Es_key_schedule keyschedule;des_set_key_unchecked ( &keyencrypt, &keyschedule); memcpy (Ivec, Cbc_iv, sizeof (CBC_IV)); unsigned char* outputtext = new unsigned char[ Cleartext.length ()];memset (outputtext, 0, Cleartext.length ()), const unsigned char* tmp = (const unsigned char*) Cleartext.c_str ();D es_cfb_encrypt (TMP, Outputtext, 8, Cleartext.length (), &keyschedule, &ivec, DES_ENCRYPT); Strciphertext = (char*) outputtext;delete [] outputtext;} Break;case Triple_ecb:{des_cblock Ke1, Ke2, Ke3;memset (ke1, 0, 8); memset (Ke2, 0, 8); memset (Ke2, 0, 8); if (Key.length () (=) {memcpy (Ke1, Key.c_str (), 8), memcpy (Ke2, KEY.C_STR () + 8, 8), memcpy (Ke3, key.c_str () +, 8);} else if (key.length () >= () {memcpy (Ke1, Key.c_str (), 8); memcpy (Ke2,KEY.C_STR () + 8, 8); memcpy (Ke3, key.c_str () + +, Key.length ()-16);} else if (key.length () >= 8) {memcpy (Ke1, Key.c_str (), 8), memcpy (Ke2, KEY.C_STR () + 8, Key.length ()-8); memcpy (Ke3, key . C_STR (), 8);} else {memcpy (Ke1, Key.c_str (), Key.length ()), memcpy (Ke2, Key.c_str (), Key.length ()), memcpy (Ke3, Key.c_str (), Key.length ());} Des_key_schedule ks1, Ks2, ks3;des_set_key_unchecked (&ke1, &AMP;KS1);D es_set_key_unchecked (&ke2, &AMP;KS2) ;D es_set_key_unchecked (&ke3, &AMP;KS3); Const_des_cblock Inputtext;des_cblock outputtext;vector<unsigned char> vecciphertext;unsigned Char tmp[8];for (int i = 0; i < cleartext.length ()/8; i + +) {memcpy (Inputtext, Cleart EXT.C_STR () + i * 8, 8);D Es_ecb3_encrypt (&inputtext, &outputtext, &ks1, &ks2, &AMP;KS3, DES_ENCRYPT); memcpy (TMP, Outputtext, 8); for (int j = 0; J < 8; j + +) Vecciphertext.push_back (Tmp[j]);} if (cleartext.length ()% 8! = 0) {int tmp1 = Cleartext.length ()/8 * 8;int TMP2 = cleartext.length ()-Tmp1;memseT (inputtext, 0, 8); memcpy (Inputtext, cleartext.c_str () + TMP1, TMP2);D es_ecb3_encrypt (&inputtext, &outputtext , &ks1, &ks2, &AMP;KS3, Des_encrypt); memcpy (TMP, Outputtext, 8); for (int j = 0; J < 8; j + +) Vecciphertext.push_b ACK (Tmp[j]);} Strciphertext.clear (); Strciphertext.assign (Vecciphertext.begin (), Vecciphertext.end ());} Break;case Triple_cbc:{des_cblock Ke1, Ke2, Ke3, Ivec;memset (ke1, 0, 8); memset (Ke2, 0, 8); memset (Ke2, 0, 8); if (key.length () >= () {memcpy (Ke1, Key.c_str (), 8), memcpy (Ke2, KEY.C_STR () + 8, 8), memcpy (Ke3, key.c_str () +, 8);} else if (key.  Length () >= () {memcpy (Ke1, Key.c_str (), 8); memcpy (Ke2, KEY.C_STR () + 8, 8); memcpy (Ke3, key.c_str () + key.length () -16);} else if (key.length () >= 8) {memcpy (Ke1, Key.c_str (), 8), memcpy (Ke2, KEY.C_STR () + 8, Key.length ()-8); memcpy (Ke3, key . C_STR (), 8);} else {memcpy (Ke1, Key.c_str (), Key.length ()), memcpy (Ke2, Key.c_str (), Key.length ()), memcpy (Ke3, Key.c_str (), Key.length ());} Des_key_schedule KS1, KS2, ks3;des_set_key_unchecked (&ke1, &AMP;KS1);D es_set_key_unchecked (&ke2, &ks2);D es_set_key_unchecked ( &ke3, &AMP;KS3); memcpy (Ivec, Cbc_iv, sizeof (CBC_IV)); int ilength = Cleartext.length ()% 8? (Cleartext.length ()/8 + 1) * 8:cleartext.length (); unsigned char* tmp = new unsigned char[ilength + 16];memset (tmp, 0, Ilength);D es_ede3_cbc_encrypt ((const unsigned char*) CLEARTEXT.C_STR (), TMP, Cleartext.length () +1, &AMP;KS1, &AMP;KS2 , &AMP;KS3, &ivec, des_encrypt); strciphertext = (char*) tmp;delete [] tmp;} break;} return strciphertext;} String Des_decrypt (const string ciphertext, const string key, Crypto_mode mode) {string Strcleartext;switch (mode) {case GE Neral:case Ecb:{des_cblock keyencrypt;memset (keyencrypt, 0, 8); if (Key.length () <= 8) memcpy (Keyencrypt, Key.c_str () , Key.length ()); else memcpy (Keyencrypt, Key.c_str (), 8);D Es_key_schedule keyschedule;des_set_key_unchecked (& Keyencrypt, &keyschedule); Const_des_cblock Inputtext;des_cblock Outputtext;vector<unsigned char> veccleartext;unsigned Char tmp[8];for (int i = 0; i < ciphertext.length ()/8; i + +) {memcpy (Inputtext, C IPHERTEXT.C_STR () + i * 8, 8);D Es_ecb_encrypt (&inputtext, &outputtext, &keyschedule, Des_decrypt); memcpy ( TMP, Outputtext, 8); for (int j = 0; J < 8; j + +) Veccleartext.push_back (Tmp[j]);} if (ciphertext.length ()% 8! = 0) {int tmp1 = Ciphertext.length ()/8 * 8;int TMP2 = ciphertext.length ()-Tmp1;memset (INP Uttext, 0, 8); memcpy (Inputtext, ciphertext.c_str () + TMP1, TMP2);D es_ecb_encrypt (&inputtext, &outputtext, &keyschedule, Des_decrypt) memcpy (TMP, Outputtext, 8); for (int j = 0; J < 8; j + +) Veccleartext.push_back (Tmp[j]);} Strcleartext.clear (); Strcleartext.assign (Veccleartext.begin (), Veccleartext.end ());} Break;case Cbc:{des_cblock Keyencrypt, Ivec;memset (keyencrypt, 0, 8); if (Key.length () <= 8) memcpy (Keyencrypt, key.c_ STR (), key.length ()); else memcpy (Keyencrypt, Key.c_str (), 8);D Es_key_schedule keyschedule;des_set_key_unchecked ( &keYencrypt, &keyschedule); memcpy (Ivec, Cbc_iv, sizeof (CBC_IV)); int ilength = Ciphertext.length ()% 8? (Ciphertext.length ()/8 + 1) * 8:ciphertext.length (); unsigned char* tmp = new unsigned char[ilength];memset (TMP, 0, ILe Ngth);D es_ncbc_encrypt ((const unsigned char*) CIPHERTEXT.C_STR (), TMP, Ciphertext.length () +1, &keyschedule, & Ivec, des_decrypt); strcleartext = (char*) tmp;delete [] tmp;} Break;case Cfb:{des_cblock Keyencrypt, Ivec;memset (keyencrypt, 0, 8); if (Key.length () <= 8) memcpy (Keyencrypt, key.c_ STR (), key.length ()); else memcpy (Keyencrypt, Key.c_str (), 8);D Es_key_schedule keyschedule;des_set_key_unchecked ( &keyencrypt, &keyschedule); memcpy (Ivec, Cbc_iv, sizeof (CBC_IV)); unsigned char* outputtext = new unsigned char[ Ciphertext.length ()];memset (outputtext, 0, Ciphertext.length ()), const unsigned char* tmp = (const unsigned char*) Ciphertext.c_str ();D es_cfb_encrypt (TMP, Outputtext, 8, 32/*ciphertext.length ()-16*/, &keyschedule, &ivec, Des_decrypt); STRCLEartext = (char*) outputtext;delete [] outputtext;} Break;case Triple_ecb:{des_cblock Ke1, Ke2, Ke3;memset (ke1, 0, 8); memset (Ke2, 0, 8); memset (Ke2, 0, 8); if (Key.length () (=) {memcpy (Ke1, Key.c_str (), 8), memcpy (Ke2, KEY.C_STR () + 8, 8), memcpy (Ke3, key.c_str () +, 8);} else if (key.length () >=) {memcpy (Ke1, Key.c_str (), 8), memcpy (Ke2, KEY.C_STR () + 8, 8); memcpy (Ke3, key.c_str () +, Key.length ()-16) ;} else if (key.length () >= 8) {memcpy (Ke1, Key.c_str (), 8), memcpy (Ke2, KEY.C_STR () + 8, Key.length ()-8); memcpy (Ke3, key . C_STR (), 8);} else {memcpy (Ke1, Key.c_str (), Key.length ()), memcpy (Ke2, Key.c_str (), Key.length ()), memcpy (Ke3, Key.c_str (), Key.length ());} Des_key_schedule ks1, Ks2, ks3;des_set_key_unchecked (&ke1, &AMP;KS1);D es_set_key_unchecked (&ke2, &AMP;KS2) ;D es_set_key_unchecked (&ke3, &AMP;KS3); Const_des_cblock Inputtext;des_cblock outputtext;vector<unsigned char> veccleartext;unsigned Char tmp[8];for (int i = 0; i < ciphertext.length ()/8; i + +)) {memcpy (Inputtext, ciphertext.c_str () + i * 8, 8);D Es_ecb3_encrypt (&inputtext, &outputtext, &AMP;KS1, &AMP;KS2 , &AMP;KS3, Des_decrypt) memcpy (TMP, Outputtext, 8); for (int j = 0; J < 8; j + +) Veccleartext.push_back (Tmp[j]);} if (ciphertext.length ()% 8! = 0) {int tmp1 = Ciphertext.length ()/8 * 8;int TMP2 = ciphertext.length ()-Tmp1;memset (INP Uttext, 0, 8); memcpy (Inputtext, ciphertext.c_str () + TMP1, TMP2);D es_ecb3_encrypt (&inputtext, &outputtext, &AMP;KS1, &ks2, &AMP;KS3, Des_decrypt) memcpy (TMP, Outputtext, 8); for (int j = 0; J < 8; j + +) Veccleartext.push_back (Tmp[j]);} Strcleartext.clear (); Strcleartext.assign (Veccleartext.begin (), Veccleartext.end ());} Break;case Triple_cbc:{des_cblock Ke1, Ke2, Ke3, Ivec;memset (ke1, 0, 8); memset (Ke2, 0, 8); memset (Ke2, 0, 8); if (key.length () >= () {memcpy (Ke1, Key.c_str (), 8), memcpy (Ke2, KEY.C_STR () + 8, 8), memcpy (Ke3, key.c_str () +, 8);} else if (key. Length () >=) {memcpy (Ke1, Key.c_str (), 8); memcpy (Ke2, Key.c_str() + 8, 8); memcpy (Ke3, key.c_str () + key.length ()-16);} else if (key.length () >= 8) {memcpy (Ke1, Key.c_str (), 8), memcpy (Ke2, KEY.C_STR () + 8, Key.length ()-8); memcpy (Ke3, key . C_STR (), 8);} else {memcpy (Ke1, Key.c_str (), Key.length ()), memcpy (Ke2, Key.c_str (), Key.length ()), memcpy (Ke3, Key.c_str (), Key.length ());} Des_key_schedule ks1, Ks2, ks3;des_set_key_unchecked (&ke1, &AMP;KS1);D es_set_key_unchecked (&ke2, &AMP;KS2) ;D es_set_key_unchecked (&ke3, &AMP;KS3); memcpy (Ivec, Cbc_iv, sizeof (CBC_IV)); int ilength = Ciphertext.length ()% 8? (Ciphertext.length ()/8 + 1) * 8:ciphertext.length (); unsigned char* tmp = new unsigned char[ilength];memset (TMP, 0, ILe Ngth);D es_ede3_cbc_encrypt ((const unsigned char*) CIPHERTEXT.C_STR (), TMP, Ciphertext.length () +1, &AMP;KS1, &ks2, &AMP;KS3, &ivec, des_decrypt); strcleartext = (char*) tmp;delete [] tmp;} break;} return strcleartext;}

3. Main.cpp:

#include "stdafx.h" #include "cryptotest.h" #include <iostream> #include <string>using namespace std;void Test_des () {String cleartext = "Beijing, China 12345$abcde%[email protected]!!!!"; String ciphertext = ""; string key = "BEIJINGCHINA1234567890ABCDEFGH!!!"; Crypto_mode MODE = Triple_cbc;ciphertext = Des_encrypt (cleartext, Key, MODE); string decrypt = Des_decrypt (ciphertext, key , mode);cout<< "src cleartext:" <<cleartext<<endl;cout<< "genarate ciphertext:" << ciphertext<<endl;cout<< "src ciphertext:" <<ciphertext<<endl;cout<< "genarate Cleartext: "<<decrypt<<endl;if (strcmp (Cleartext.c_str (), decrypt.c_str ()) = = 0) cout<<" DES Crypto OK!!! " <<endl;elsecout<< "DES Crypto Error!!!" <<endl;} int main (int argc, char* argv[]) {test_des ();cout<< "OK!!!" <<endl;return 0;}

Example of use of symmetric encryption algorithm des common functions in OpenSSL