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; @endDES3Util.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
来源:https://www.cnblogs.com/wanyakun/p/3403352.html