AES加密是对称加密的一种，全称是Advanced Encryption Standard(高级加密标准)。常用于网络传输中的数据加解密。

图片.png

//
//  NSData+AESEncryption.h
//  ownloadData
//
//  Created by CZ on 2023/7/25.
//

#import <Foundation/Foundation.h>

NS_ASSUME_NONNULL_BEGIN

@interface NSData (AESEncryption)

- (NSData *)AES128ParmEncryptWithKey:(NSString *)key iv:(NSString *)iv;
- (NSData *)AES128ParmDecryptWithKey:(NSString *)key iv:(NSString *)iv;

@end

NS_ASSUME_NONNULL_END

//
//  NSData+AESEncryption.m
//  ownloadData
//
//  Created by 陈镇 on 2023/7/25.
//

#import <CommonCrypto/CommonCryptor.h>
#import "NSData+AESEncryption.h"

@implementation NSData (AESEncryption)
- (NSData *)AES128ParmEncryptWithKey:(NSString *)key iv:(NSString *)iv
{
    char keyPtr[kCCKeySizeAES128+1];
    bzero(keyPtr, sizeof(keyPtr));
    [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];
    
    char ivPtr[kCCBlockSizeAES128 + 1];
    bzero(ivPtr, sizeof(ivPtr));
    [iv getCString:ivPtr maxLength:sizeof(ivPtr) encoding:NSUTF8StringEncoding];

    
    NSUInteger dataLength = [self length];
    size_t bufferSize = dataLength + kCCKeySizeAES128;
    void *buffer = malloc(bufferSize);
    size_t numBytesEncrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES,
                                          kCCOptionPKCS7Padding,
                                          keyPtr, kCCKeySizeAES128,
                                          ivPtr,
                                          [self bytes], dataLength,
                                          buffer, bufferSize,
                                          &numBytesEncrypted);
    if (cryptStatus == kCCSuccess) {
        return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];
    }
    free(buffer);
    return nil;
}
//解密
- (NSData *)AES128ParmDecryptWithKey:(NSString *)key iv:(NSString *)iv
{
    char keyPtr[kCCKeySizeAES128 + 1];
    bzero(keyPtr, sizeof(keyPtr));
    [key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];
    
    char ivPtr[kCCBlockSizeAES128 + 1];
    bzero(ivPtr, sizeof(ivPtr));
    [iv getCString:ivPtr maxLength:sizeof(ivPtr) encoding:NSUTF8StringEncoding];
    
    NSUInteger dataLength = [self length];
    size_t bufferSize = dataLength + kCCKeySizeAES128;
    void *buffer = malloc(bufferSize);
    size_t numBytesDecrypted = 0;
    CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt,
                                          kCCAlgorithmAES,
                                          kCCOptionPKCS7Padding,
                                          keyPtr,
                                          kCCKeySizeAES128,
                                          ivPtr,
                                          [self bytes], dataLength,
                                          buffer, bufferSize,
                                          &numBytesDecrypted);
    if (cryptStatus == kCCSuccess) {
        NSData *t = [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted];        
        return t;
    }
    free(buffer);
    return nil;
}
@end

使用

    //base64字符串转data （text是待解析的base64字符串）
    NSData *data = [[NSData alloc] initWithBase64EncodedString:text options:NSDataBase64DecodingIgnoreUnknownCharacters];
    //aes解析
    NSData *tttt = [data AES128ParmDecryptWithKey:key iv:iv];

    //解析结果
    NSString *str = [[NSString alloc] initWithData:tttt encoding:NSUTF8StringEncoding];
    RTLog(@"---- %@",str);

参考文档
参考文档2