iOS AES128 CBC No Padding加密解密

最近的项目中数据传输用到加密，项目选择了AES128 CBC No Padding加密方式，PHP和Android方面的代码网上太多了。但是唯独没有iOS的，但是也有别的写法，但不是是AES128 CBC No Padding或者不是CBC No Padding。自己仿照着写了个，不过PHP端总是解密不出。问题就处在No Padding. No Pading的情况下，一定要对加密数据不是kCCKeySizeAES128倍数部分进行0x0000的填充，不然加密长度不正确，一般情况下选择使用kCCOptionPKCS7Padding（也就是0x0001）进行填充，但是我们是No Padding所以要用0x0000填充。加密后再对加密数据进行了Base64加密，用到了google的GTMBase64，没有的网上自己找，下面上ios的代码：

DES3Util.h内容

//

//  DES3Util.h

//  JuziAnalyticsDemo

//

//  Created by wanyakun on 13-6-6.

//  Copyright (c) 2013年 The9. All rights reserved.

//

#import <Foundation/Foundation.h>

@interface DES3Util : NSObject

+ (NSString*) AES128Encrypt:(NSString *)plainText;

+ (NSString*) AES128Decrypt:(NSString *)encryptText;

@end

DES3Util.m文件内容

//

//  DES3Util.m

//  JuziAnalyticsDemo

//

//  Created by wanyakun on 13-6-6.

//  Copyright (c) 2013年 The9. All rights reserved.

//

#import "DES3Util.h"

#import <CommonCrypto/CommonCryptor.h>

#import "GTMBase64.h"

#define gkey			@"16位长度的字符串" //自行修改

#define gIv             @"16位长度的字符串" //自行修改

@implementation DES3Util

+(NSString *)AES128Encrypt:(NSString *)plainText

{

    char keyPtr[kCCKeySizeAES128+1];

    memset(keyPtr, 0, sizeof(keyPtr));

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

    char ivPtr[kCCBlockSizeAES128+1];

    memset(ivPtr, 0, sizeof(ivPtr));

    [gIv getCString:ivPtr maxLength:sizeof(ivPtr) encoding:NSUTF8StringEncoding];

    NSData* data = [plainText dataUsingEncoding:NSUTF8StringEncoding];

    NSUInteger dataLength = [data length];

    int diff = kCCKeySizeAES128 - (dataLength % kCCKeySizeAES128);

    int newSize = 0;

    if(diff > 0)

    {

        newSize = dataLength + diff;

    }

    char dataPtr[newSize];

    memcpy(dataPtr, [data bytes], [data length]);

    for(int i = 0; i < diff; i++)

    {

        dataPtr[i + dataLength] = 0x00;

    }

    size_t bufferSize = newSize + kCCBlockSizeAES128;

    void *buffer = malloc(bufferSize);

    memset(buffer, 0, bufferSize);

    size_t numBytesCrypted = 0;

    CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt,

                                          kCCAlgorithmAES128,

                                          0x0000,               //No padding

                                          keyPtr,

                                          kCCKeySizeAES128,

                                          ivPtr,

                                          dataPtr,

                                          sizeof(dataPtr),

                                          buffer,

                                          bufferSize,

                                          &numBytesCrypted);

    if (cryptStatus == kCCSuccess) {

        NSData *resultData = [NSData dataWithBytesNoCopy:buffer length:numBytesCrypted];

        return [GTMBase64 stringByEncodingData:resultData];

    }

    free(buffer);

    return nil;

}

+(NSString *)AES128Decrypt:(NSString *)encryptText

{

    char keyPtr[kCCKeySizeAES128 + 1];

    memset(keyPtr, 0, sizeof(keyPtr));

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

    char ivPtr[kCCBlockSizeAES128 + 1];

    memset(ivPtr, 0, sizeof(ivPtr));

    [gIv getCString:ivPtr maxLength:sizeof(ivPtr) encoding:NSUTF8StringEncoding];

    NSData *data = [GTMBase64 decodeData:[encryptText dataUsingEncoding:NSUTF8StringEncoding]];

    NSUInteger dataLength = [data length];

    size_t bufferSize = dataLength + kCCBlockSizeAES128;

    void *buffer = malloc(bufferSize);

    size_t numBytesCrypted = 0;

    CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt,

                                          kCCAlgorithmAES128,

                                          0x0000,

                                          keyPtr,

                                          kCCBlockSizeAES128,

                                          ivPtr,

                                          [data bytes],

                                          dataLength,

                                          buffer,

                                          bufferSize,

                                          &numBytesCrypted);

    if (cryptStatus == kCCSuccess) {

        NSData *resultData = [NSData dataWithBytesNoCopy:buffer length:numBytesCrypted];

        return [[[NSString alloc] initWithData:resultData encoding:NSUTF8StringEncoding] autorelease];

    }

    free(buffer);

    return nil;

}

@end

巴特西

iOS AES128 CBC No Padding加密解密

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