使用Microsoft CryptoAPI进行加密、解密、签名及验证(代码)

 

#include <stdio.h>

#include <windows.h>

#include <wincrypt.h>

#define MY_ENCODING_TYPE (PKCS_7_ASN_ENCODING | X509_ASN_ENCODING)

#define KEYLENGTH 0x00800000

void HandleError(char *s);

 

//--------------------------------------------------------------------

// These additional #define statements are required.

#define ENCRYPT_ALGORITHM CALG_RC4

#define ENCRYPT_BLOCK_SIZE 8

#define MAX_FILE_SIZE 4000000

#define SIGNATURE_SIZE 500

 

BYTE *pbKeyBlob; //用来保存导出的公钥

DWORD dwBlobLen;

 

//   Declare the functions. The function definition

//   follows main.

BOOL VerifyFile (

                    PCHAR szSource,                         

                    PCHAR szDestination);

BOOL SignFile   (

                    PCHAR szSource,                         

                    PCHAR szDestination);

BOOL DecryptFile(

                    PCHAR szSource,

                    PCHAR szDestination,

                    PCHAR szPassword);

 

BOOL EncryptFile(

                    PCHAR szSource,

                    PCHAR szDestination,

                    PCHAR szPassword);

 

//--------------------------------------------------------------------

//   Begin main.

 

void main(void)

{

     CHAR szSource[100];

     CHAR szDestination[100];

     CHAR szPassword[100];

 

    

     //--------------------------------------------------------------------

     // Call EncryptFile to do the actual encryption.   加密文件

     printf("/n------------------------------------------------------------/n");

     printf("/n/n1.Encrypt a file. /n/n");

     printf("/nEnter the name of the file to be encrypted: ");

     scanf("%s",szSource);

     printf("/nEnter the name of the output file: ");

     scanf("%s",szDestination);

     printf("/nEnter the password:");

     scanf("%s",szPassword);

 

     if(EncryptFile(szSource, szDestination, szPassword))

     {

     printf("/nEncryption of the file %s was a success. /n", szSource);

     printf("/nThe encrypted data is in file %s./n",szDestination);

     }

     else

     {

     HandleError("/nError encrypting file!");

     }

 

 

     //--------------------------------------------------------------------

     // Call Decryptfile to do the actual decryption.   解密文件

     printf("/n------------------------------------------------------------/n");

     printf("/n/n2.Decrypt a file. /n/n");

     printf("/nEnter the name of the file to be decrypted: ");

     scanf("%s",szSource);

     printf("/nEnter the name of the output file: ");

     scanf("%s",szDestination);

     printf("/nEnter the password:");

     scanf("%s",szPassword);

 

     if(DecryptFile(szSource, szDestination, szPassword))

     {

     printf("/nDecryption of the file %s was a success. /n", szSource);

     printf("/nThe decrypted data is in file %s./n",szDestination);

     }

     else

     {

     HandleError("/nError decrypting file!");

     }

    

     //--------------------------------------------------------------------

     // Call SignFile to do the actual signature             签名文件

     printf("/n------------------------------------------------------------/n");

     printf("/n/n3.Sign a file. /n/n");

     printf("/nEnter the name of the file to be signed: ");

     scanf("%s",szSource);

     printf("/nEnter the name of the signature file: ");

     scanf("%s",szDestination);

 

     if(SignFile(szSource, szDestination))

     {

         printf("/nSignature of the file %s was a success. /n", szSource);

         printf("/nThe signature data is in file %s./n",szDestination);

     }

     else

     {

         HandleError("/nError while signing the file!");

     }

 

     //---------------------------------------------------------------------

     // Call VerifyFile to do the actual verification   验证签名

     printf("/n------------------------------------------------------------/n");

     printf("/n/n4.Verify a file and its signature. /n/n");

     printf("/nEnter the name of the file to be verified: ");

     scanf("%s",szSource);

     printf("/nEnter the name of the signature file: ");

     scanf("%s",szDestination);

     //printf("/nEnter the name of the public key file: ");

     //scanf("%s",szDestination);

 

     if(VerifyFile(szSource, szDestination))

     {

         printf("/nVerification of the file %s was a success. /n", szSource);

     }

     else

     {

         HandleError("/nVerification failed. Error file!");

     }

 

} // End of main