IOS 与 PHP 通信加密，使用AES 128 CBC no padding

这个网上的资料真实浩如烟海，但是真正有价值的屈指可数

自己尝试了一天多，终于还是搞定了。

再次要感谢网上的前辈么。

比如下面这个关于php和java端的实现：

关于php和java端的实现。

再比如下面这个关于ios端的实现：

为何要采用 no padding 这种形式：

AES加密如果原输入数据不够16字节的整数位，就要补齐，如果采用

pkcs7或者pkcs5这种加密方式，末端添加的数据可能是0x1,0x2,0x3，不固定，

在解码后需要把末端多余的字符去掉，就显得比较棘手。

如果不管补齐多少位，末端都是'\0',去掉的话比较容易操作。

好了，再次确认一下，这里使用的是  AES128 CBC no padding加密解密方式。

先上ios端的代码：

 
////  AES128.m//  login////  Created by wangdan on 15-3-3.//  Copyright (c) 2015年 wangdan. All rights reserved.//#import "AES128.h"#import #import "GTMBase64.h"@implementation AES128+(NSString *)AES128Encrypt:(NSString *)plainText withKey:(NSString *)key{        if( ![self validKey:key] ){        return nil;    }        char keyPtr[kCCKeySizeAES128+1];    memset(keyPtr, 0, sizeof(keyPtr));    [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];            char ivPtr[kCCBlockSizeAES128+1];    memset(ivPtr, 0, sizeof(ivPtr));    [key getCString:ivPtr maxLength:sizeof(ivPtr) encoding:NSUTF8StringEncoding];        NSData* data = [plainText dataUsingEncoding:NSUTF8StringEncoding];    NSUInteger dataLength = [data length];        int diff = kCCKeySizeAES128 - (dataLength % kCCKeySizeAES128);    unsigned long newSize = 0;        if(diff > 0)    {        newSize = dataLength + diff;        NSLog(@"diff is %d",diff);    }        char dataPtr[newSize];    memcpy(dataPtr, [data bytes], [data length]);    for(int i = 0; i < diff; i++)    {        dataPtr[i + dataLength] =0x0000;    }        size_t bufferSize = newSize + kCCBlockSizeAES128;    void *buffer = malloc(bufferSize);    memset(buffer, 0, bufferSize);        size_t numBytesCrypted = 0;        CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt,                                          kCCAlgorithmAES128,                                          0x0000,                                          [key UTF8String],                                          kCCKeySizeAES128,                                          [key UTF8String],                                          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 *)processDecodedString:(NSString *)decoded{    if( decoded==nil || decoded.length==0 ){        return nil;    }    const char *tmpStr=[decoded UTF8String];    int i=0;        while( tmpStr[i]!='\0' )    {        i++;    }    NSString *final=[[NSString alloc]initWithBytes:tmpStr length:i encoding:NSUTF8StringEncoding];    return final;    }+(NSString *)AES128Decrypt:(NSString *)encryptText withKey:(NSString *)key{        if( ![self validKey:key] ){        return nil;    }        char keyPtr[kCCKeySizeAES128 + 1];    memset(keyPtr, 0, sizeof(keyPtr));    [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];        char ivPtr[kCCBlockSizeAES128 + 1];    memset(ivPtr, 0, sizeof(ivPtr));    [key 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,                                          [key UTF8String],                                          kCCBlockSizeAES128,                                          [key UTF8String],                                          [data bytes],                                          dataLength,                                          buffer,                                          bufferSize,                                          &numBytesCrypted);    if (cryptStatus == kCCSuccess) {        NSData *resultData = [NSData dataWithBytesNoCopy:buffer length:numBytesCrypted];                NSString *decoded=[[NSString alloc] initWithData:resultData encoding:NSUTF8StringEncoding];        return [self processDecodedString:decoded];    }        free(buffer);    return nil;    }+(BOOL)validKey:(NSString*)key{    if( key==nil || key.length !=16 ){        return NO;    }    return YES;}-(NSString *)processDecodedString:(NSString *)decoded{    if( decoded==nil || decoded.length==0 ){        return nil;    }    const char *tmpStr=[decoded UTF8String];    int i=0;        while( tmpStr[i]!='\0' )    {        i++;    }    NSString *final=[[NSString alloc]initWithBytes:tmpStr length:i encoding:NSUTF8StringEncoding];    return final;    }@end
  
  

 上述代码需要说明的是，进行AES编码时，输入编码必须是16字节的整数倍，不然调用ios 的系统api会报错 -4003
  
补齐的字节数全部填充为0
  
 
  
另外  processDecodedString这个函数为了把解码后的字符串，末尾去掉'\0'
  
 
  
下面是PHP端的代码，这个代码是大神些写的啊，经过实际实验是能使用的：
  
<?php$privateKey = "1234567812345678";$iv     = "1234567812345678";$data   = "Test String"; //加密$encrypted = mcrypt_encrypt(MCRYPT_RIJNDAEL_128, $privateKey, $data, MCRYPT_MODE_CBC, $iv);echo(base64_encode($encrypted));echo '
'; //解密$encryptedData = base64_decode("2fbwW9+8vPId2/foafZq6Q==");$decrypted = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $privateKey, $encryptedData, MCRYPT_MODE_CBC, $iv);echo($decrypted);?>