iOS 3DES加密

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-(NSString *)TripleDES:(NSString *)plainText encryptOrDecrypt:(CCOperation)encryptOrDecrypt encryptOrDecryptKey:(NSString *)encryptOrDecryptKey

{

     

    const void *vplainText;

    size_t plainTextBufferSize;

     

    if (encryptOrDecrypt == kCCDecrypt)//解密

    {

        NSData *EncryptData = [GTMBase64 decodeData:[plainText dataUsingEncoding:NSUTF8StringEncoding]];

        plainTextBufferSize = [EncryptData length];

        vplainText = [EncryptData bytes];

    }

    else //加密

    {

        NSData* data = [plainText dataUsingEncoding:NSUTF8StringEncoding];

        plainTextBufferSize = [data length];

        vplainText = (const void *)[data bytes];

    }

     

    CCCryptorStatus ccStatus;

    uint8_t *bufferPtr = NULL;

    size_t bufferPtrSize = 0;

    size_t movedBytes = 0;

     

    bufferPtrSize = (plainTextBufferSize + kCCBlockSize3DES) & ~(kCCBlockSize3DES - 1);

    bufferPtr = malloc( bufferPtrSize * sizeof(uint8_t));

    memset((void *)bufferPtr, 0x0, bufferPtrSize);

    // memset((void *) iv, 0x0, (size_t) sizeof(iv));

     

    const void *vkey = (const void *)[encryptOrDecryptKey UTF8String];

    // NSString *initVec = @"init Vec";

    //const void *vinitVec = (const void *) [initVec UTF8String];

    //  Byte iv[] = {0x12, 0x34, 0x56, 0x78, 0x90, 0xAB, 0xCD, 0xEF};

    ccStatus = CCCrypt(encryptOrDecrypt,

                       kCCAlgorithm3DES,

                       kCCOptionPKCS7Padding | kCCOptionECBMode,

                       vkey,

                       kCCKeySize3DES,

                       nil,

                       vplainText,

                       plainTextBufferSize,

                       (void *)bufferPtr,

                       bufferPtrSize,

                       &movedBytes);

    //if (ccStatus == kCCSuccess) NSLog(@"SUCCESS");

    /*else if (ccStatus == kCC ParamError) return @"PARAM ERROR";

     else if (ccStatus == kCCBufferTooSmall) return @"BUFFER TOO SMALL";

     else if (ccStatus == kCCMemoryFailure) return @"MEMORY FAILURE";

     else if (ccStatus == kCCAlignmentError) return @"ALIGNMENT";

     else if (ccStatus == kCCDecodeError) return @"DECODE ERROR";

     else if (ccStatus == kCCUnimplemented) return @"UNIMPLEMENTED"; */

     

    NSString *result;

     

    if (encryptOrDecrypt == kCCDecrypt)

    {

        result = [[[NSString alloc] initWithData:[NSData dataWithBytes:(const void *)bufferPtr

                                                                length:(NSUInteger)movedBytes]

                                        encoding:NSUTF8StringEncoding]

                  autorelease];

    }

    else

    {

        NSData *myData = [NSData dataWithBytes:(const void *)bufferPtr length:(NSUInteger)movedBytes];

        result = [GTMBase64 stringByEncodingData:myData];

    }

     

    return result;

}