iOS 3DES加密

浏览数：28 / 时间：2015年06月11日

本文转载至 http://www.cocoachina.com/bbs/read.php?tid=177167
-(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;
}
 