iOS開發(fā)中DES的加密和解密

需要初始化iv的DES加密。(CBC模式)

兩個(gè)iv任選其一,必須要和你的后臺(tái)對(duì)應(yīng)。(CBC模式)
const Byte iv[] = {1,2,3,4,5,6,7,8};
const Byte iv[] = {0,1,2,3,4,5,6,7};

/// 需要初始化iv的DES加密。(CBC模式)
+ (NSString *)encodeDesCBCWithString:(NSString*)stringCBC {
    
    NSData*data;
//    NSString*ciphertext =nil;
    NSData *textData = [stringCBC dataUsingEncoding:NSUTF8StringEncoding];
    NSUInteger dataLength = [textData length];
    unsigned char buffer[1024];
    
    memset(buffer,0,sizeof(char));
    size_t numBytesEncrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmDES,
                                          kCCOptionPKCS7Padding ,
                                          [kASDESKEY UTF8String],kCCKeySizeDES,
                                          iv,
                                          [textData bytes], dataLength,
                                          buffer,1024,
                                          &numBytesEncrypted);
    
    if(cryptStatus ==kCCSuccess) {
        
        data = [NSData dataWithBytes:buffer length:(NSUInteger)numBytesEncrypted];
    }
    
    NSString *result = [data base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
    
    return result;
    
}

需要初始化iv的DES解密。(CBC模式)

/// 需要初始化iv的DES解密。(CBC模式)
+ (NSString*)decodeDesCBCWithString:(NSString *)stringCBC {
    
//    NSData*plaindata =nil;
    NSString*plaintext =nil;
    //    NSData *cipherdata = [GTMBase64 decodeString:stringCBC];
    NSData *cipherdata = [[NSData alloc] initWithBase64EncodedString:stringCBC options:NSDataBase64DecodingIgnoreUnknownCharacters];
    unsigned char buffer[1024];
    
    memset(buffer,0,sizeof(char));
    size_t numBytesDecrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmDES,
                                          kCCOptionPKCS7Padding ,
                                          [kASDESKEY UTF8String],kCCKeySizeDES,
                                          iv,
                                          [cipherdata bytes], [cipherdata length],
                                          buffer,1024,
                                          &numBytesDecrypted);
    
    if (cryptStatus ==kCCSuccess) {
        
        NSData*plaindata = [NSData dataWithBytes:buffer length:(NSUInteger)numBytesDecrypted];
        plaintext = [[NSString alloc]initWithData:plaindata encoding:NSUTF8StringEncoding];
        
    }
    
    return plaintext;
    
}

不需要初始化iv的DES加密。(ECB模式)

/// 不需要初始化iv的DES加密。(ECB模式)
+ (NSString *)encodeDesECBWithString:(NSString*)stringECB {
    
    NSData*data;
//    NSString*ciphertext =nil;
    NSData *textData = [stringECB dataUsingEncoding:NSUTF8StringEncoding];
    NSUInteger dataLength = [textData length];
    unsigned char buffer[1024];
    
    memset(buffer,0,sizeof(char));
    size_t numBytesEncrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmDES,
                                          kCCOptionPKCS7Padding | kCCOptionECBMode,
                                          [kASDESKEY UTF8String],kCCKeySizeDES,
                                          NULL,
                                          [textData bytes], dataLength,
                                          buffer,1024,
                                          &numBytesEncrypted);
    if(cryptStatus ==kCCSuccess) {
        
        data = [NSData dataWithBytes:buffer length:(NSUInteger)numBytesEncrypted];
    }
    
    NSString *result = [data base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];
    
    return result;
    
}

不需要初始化iv的DES解密。(ECB模式)

/// 不需要初始化iv的DES解密。(ECB模式)
+ (NSString*)decodeDesECBWithString:(NSString *)stringECB {
    
//    NSData*plaindata = nil;
    NSString*plaintext = nil;
    //    NSData *cipherdata = [GTMBase64 decodeString:stringECB];
    NSData *cipherdata = [[NSData alloc] initWithBase64EncodedString:stringECB options:NSDataBase64DecodingIgnoreUnknownCharacters];
    unsigned char buffer[1024];
    
    memset(buffer,0,sizeof(char));
    size_t numBytesDecrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmDES,
                                          kCCOptionPKCS7Padding | kCCOptionECBMode,
                                          [kASDESKEY UTF8String],kCCKeySizeDES,
                                          NULL,
                                          [cipherdata bytes], [cipherdata length],
                                          buffer,1024,
                                          &numBytesDecrypted);
    
    if (cryptStatus == kCCSuccess) {
        
        NSData*plaindata = [NSData dataWithBytes:buffer length:(NSUInteger)numBytesDecrypted];
        plaintext = [[NSString alloc]initWithData:plaindata encoding:NSUTF8StringEncoding];
    }
    return plaintext;
}

DES16進(jìn)制加密

/// 使用DES加密方法
+ (NSString *)encodeDesWithString:(NSString *)string {
    NSString *ciphertext = nil;
    const char *textBytes = [string UTF8String];
    size_t dataLength = [string length];
    //==================
    
    uint8_t *bufferPtr = NULL;
    size_t bufferPtrSize = 0;
    size_t movedBytes = 0;
    
    bufferPtrSize = (dataLength + kCCBlockSizeDES) & ~(kCCBlockSizeDES - 1);
    bufferPtr = malloc( bufferPtrSize * sizeof(uint8_t));
    memset((void *)bufferPtr, 0x0, bufferPtrSize);
    
    
    NSString *testString = kASDESKEY;
    NSData *testData = [testString dataUsingEncoding: NSUTF8StringEncoding];
    Byte *iv = (Byte *)[testData bytes];
    
    
    CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmDES,
                                          kCCOptionPKCS7Padding,
                                          [kASDESKEY UTF8String], kCCKeySizeDES,
                                          iv,
                                          textBytes, dataLength,
                                          (void *)bufferPtr, bufferPtrSize,
                                          &movedBytes);
    if (cryptStatus == kCCSuccess) {
        
        ciphertext= [ASKDESTools parseByte2HexString:bufferPtr :(int)movedBytes];

    }
    ciphertext=[ciphertext uppercaseString];//字符變大寫
    
    return ciphertext;
}

DES16進(jìn)制解密

/// 使用DES進(jìn)行解密計(jì)算
+ (NSString *)decodeDesWithString:(NSString *)string {
    
    NSData* cipherData = [ASKDESTools convertHexStrToData:[string lowercaseString]];
    
    unsigned char buffer[1024];
    memset(buffer, 0, sizeof(char));
    size_t numBytesDecrypted = 0;
    NSString *testString = kASDESKEY;
    NSData *testData = [testString dataUsingEncoding: NSUTF8StringEncoding];
    Byte *iv = (Byte *)[testData bytes];
    CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt,
                                          kCCAlgorithmDES,
                                          kCCOptionPKCS7Padding,
                                          [kASDESKEY UTF8String],
                                          kCCKeySizeDES,
                                          iv,
                                          [cipherData bytes],
                                          [cipherData length],
                                          buffer,
                                          1024,
                                          &numBytesDecrypted);
    NSString* plainText = nil;
    if (cryptStatus == kCCSuccess) {
        NSData* data = [NSData dataWithBytes:buffer length:(NSUInteger)numBytesDecrypted];
        plainText = [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
    }
    return plainText;

}

加密解密中有兩個(gè)方法調(diào)用,其實(shí)是為了16進(jìn)制與data之間的轉(zhuǎn)換。有些公司并未轉(zhuǎn)換成16進(jìn)制,而是需要跟base64共同加解密。方法適用,只需要將得出的plainText 的值轉(zhuǎn)成base64即可。

加密時(shí)轉(zhuǎn)成16進(jìn)制

+ (NSString *) parseByte2HexString:(Byte *) bytes  :(int)len {
    
    
    NSString *hexStr = @"";
    
    if(bytes)
    {
        for(int i = 0; i < len ; i++)
        {
            NSString *newHexStr = [NSString stringWithFormat:@"%x",bytes[i]&0xff]; ///16進(jìn)制數(shù)
            if([newHexStr length]==1)
                hexStr = [NSString stringWithFormat:@"%@0%@",hexStr,newHexStr];
            else
            {
                hexStr = [NSString stringWithFormat:@"%@%@",hexStr,newHexStr];
            }
            
        }
    }
    
    return hexStr;
}

解密時(shí)轉(zhuǎn)回data

+ (NSData *)convertHexStrToData:(NSString *)str {
    if (!str || [str length] == 0) {
        return nil;
    }
    
    NSMutableData *hexData = [[NSMutableData alloc] initWithCapacity:8];
    NSRange range;
    if ([str length] % 2 == 0) {
        range = NSMakeRange(0, 2);
    } else {
        range = NSMakeRange(0, 1);
    }
    for (NSInteger i = range.location; i < [str length]; i += 2) {
        unsigned int anInt;
        NSString *hexCharStr = [str substringWithRange:range];
        NSScanner *scanner = [[NSScanner alloc] initWithString:hexCharStr];
        
        [scanner scanHexInt:&anInt];
        NSData *entity = [[NSData alloc] initWithBytes:&anInt length:1];
        [hexData appendData:entity];
        
        range.location += range.length;
        range.length = 2;
    }
    
    return hexData;
}

注意:
1、DES的加密模式有ECB和CBC。
2、iOS的填充模式只有 kCCOptionPKCS7Padding 和kCCOptionPKCS7Padding | kCCOptionECBMode兩種。而后臺(tái)填充模式就多了,這就需要一一對(duì)應(yīng)才能實(shí)現(xiàn)加密和解密。
3、具體的對(duì)應(yīng)模式是java的DES/ECB/PKCS5Padding對(duì)應(yīng)iOS的kCCOptionPKCS7Padding | kCCOptionECBMode;DES/CBC/PKCS5Padding對(duì)應(yīng)ios的kCCOptionPKCS7Padding 。

Simulator Screen Shot - iPhone 11 Pro Max - 2020-04-30 at 16.17.14.png

Demo下載地址

最后編輯于
?著作權(quán)歸作者所有,轉(zhuǎn)載或內(nèi)容合作請(qǐng)聯(lián)系作者
【社區(qū)內(nèi)容提示】社區(qū)部分內(nèi)容疑似由AI輔助生成,瀏覽時(shí)請(qǐng)結(jié)合常識(shí)與多方信息審慎甄別。
平臺(tái)聲明:文章內(nèi)容(如有圖片或視頻亦包括在內(nèi))由作者上傳并發(fā)布,文章內(nèi)容僅代表作者本人觀點(diǎn),簡(jiǎn)書系信息發(fā)布平臺(tái),僅提供信息存儲(chǔ)服務(wù)。

相關(guān)閱讀更多精彩內(nèi)容

  • 1. ASCII 編碼 ASCII(American Standard Code for Information ...
    s酸菜閱讀 8,875評(píng)論 0 8
  • 概述 之前一直對(duì)加密相關(guān)的算法知之甚少,只知道類似DES、RSA等加密算法能對(duì)數(shù)據(jù)傳輸進(jìn)行加密,且各種加密算法各有...
    Henryzhu閱讀 3,231評(píng)論 0 14
  • 在介紹加密算法之前, 先介紹一下 base64: 0. base64 Base64要求把每三個(gè)8Bit的字節(jié)轉(zhuǎn)換為...
    reboot_q閱讀 13,763評(píng)論 3 8
  • 1、簡(jiǎn)介對(duì)稱加密算法又稱傳統(tǒng)加密算法。加密和解密使用同一個(gè) 密鑰。 1.1對(duì)稱加密算法示例密鑰:X加密算法:每個(gè)字...
    6ffd6634d577閱讀 3,101評(píng)論 0 2
  • 加密的原因:保證數(shù)據(jù)安全 加密必備要素:1、明文/密文 2、秘鑰 3、算法 秘鑰:在密碼學(xué)中是一個(gè)定長(zhǎng)的字符串...
    Winnifred_閱讀 13,457評(píng)論 0 3

友情鏈接更多精彩內(nèi)容