iOS之加密的三种方法

//需要导入   #import <CommonCrypto/CommonCryptor.h> 

==============MD5加密============ 

NSString *str = @"加密的内容"; 

        //转换成C语言的字符串 

        const char *cStr=[str UTF8String]; 

        //MD5加密的结果是128位，需要开辟一个16字节的空间 

        unsigned char result[16]; 

        //调用加密函数 

        CC_MD5(cStr, (unsigned int)strlen(cStr), result); 

        //通过上面这个方法获取的MD5是一个16个字符的数组，需要转换成32位的MD5值 

        NSMutableString *string = [NSMutableString stringWithCapacity:10]; 

        for (int i=; i<16; i++) { 

            [string appendString:[NSString stringWithFormat:@"%02x",result[i]]]; 

        } 

        NSLog(@"MD5加密:%@",string); 

 

===============base64加密解密============= 

//ios7 以后提供了base64的转码方式 

        //加密 

        NSString *pass=@"加密的内容"; 

        NSData *passData=[pass dataUsingEncoding:NSUTF8StringEncoding]; 

        NSString *result = [passData base64EncodedStringWithOptions:NSDataBase64EncodingEndLineWithLineFeed]; 

        NSLog(@"base64加密:%@",result); 

         

        //解密 

        NSData *decodeData = [[NSData alloc]initWithBase64EncodedString:result options:]; 

        NSString *decodeStr = [[NSString alloc]initWithData:decodeData encoding:NSUTF8StringEncoding]; 

        NSLog(@"base64解密:%@",decodeStr); 

 

================AES加密解密=============== 

//新建一个NSData类,写入一下两个方法 

//加密方法 

- (NSData*)AES256EncryptWithKey:(NSString*)key { 

     

    char keyPtr[kCCKeySizeAES256 + 1]; // room for terminator (unused) 

    bzero(keyPtr, sizeof(keyPtr)); // fill with zeroes (for padding) 

     

    [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; 

     

    NSUInteger dataLength = [self length]; 

     

    size_t bufferSize           = dataLength + kCCBlockSizeAES128; 

    void* buffer                = malloc(bufferSize); 

     

    size_t numBytesEncrypted    = ; 

    CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding, 

                                          keyPtr, kCCKeySizeAES256, 

                                          NULL /* initialization vector (optional) */, 

                                          [self bytes], dataLength, /* input */ 

                                          buffer, bufferSize, /* output */ 

                                          &numBytesEncrypted); 

     

    if (cryptStatus == kCCSuccess) { 

        return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted]; 

    } 

     

    free(buffer); 

    return nil; 

} 

//解密方法 

- (NSData*)AES256DecryptWithKey:(NSString*)key { 

     

    char keyPtr[kCCKeySizeAES256 + 1]; // room for terminator (unused) 

    bzero(keyPtr, sizeof(keyPtr)); // fill with zeroes (for padding) 

     

    // fetch key data 

    [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding]; 

     

    NSUInteger dataLength = [self length]; 

     

    size_t bufferSize           = dataLength + kCCBlockSizeAES128; 

    void* buffer                = malloc(bufferSize); 

     

    size_t numBytesDecrypted    = ; 

    CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmAES128, kCCOptionPKCS7Padding, 

                                          keyPtr, kCCKeySizeAES256, 

                                          NULL /* initialization vector (optional) */, 

                                          [self bytes], dataLength, /* input */ 

                                          buffer, bufferSize, /* output */ 

                                          &numBytesDecrypted); 

     

    if (cryptStatus == kCCSuccess) { 

        return [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted]; 

    } 

     

    free(buffer); //free the buffer; 

 

在另外的类里面调用上面NSData里面的方法 

//==========AES加密解密============= 

        NSString *key = @"mykey";//钥匙 

        NSString *secret = @"加密内容";//准备加密的内容 

        NSData *plain = [secret dataUsingEncoding:NSUTF8StringEncoding]; 

        NSData *ciper = [plain AES256EncryptWithKey:key]; 

        NSLog(@"AES加密%@",ciper); 

        //解密 

        plain = [ciper AES256DecryptWithKey:key]; 

         NSLog(@"AES解密:%@",[[NSString alloc]initWithData:plain encoding:NSUTF8StringEncoding]);