Home > Article > Backend Development > 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:
<pre class="objc" name="code">//// AES128.m// login//// Created by wangdan on 15-3-3.// Copyright (c) 2015年 wangdan. All rights reserved.//#import "AES128.h"#import <CommonCrypto/CommonCryptor.h>#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 '<br/>'; //解密$encryptedData = base64_decode("2fbwW9+8vPId2/foafZq6Q==");$decrypted = mcrypt_decrypt(MCRYPT_RIJNDAEL_128, $privateKey, $encryptedData, MCRYPT_MODE_CBC, $iv);echo($decrypted);?>