iOS,信息加解密

1.AES加解密

AES加解密

//

//  AESEncryptAndDecrypt.h

//  NSData扩展方法，用于处理aes加解密

//

//  Created by Vie on 16/4/7.

//  Copyright © 2016年 Vie. All rights reserved.

//

#import <Foundation/Foundation.h>

@class NSString;

@interface NSData (AES)

- (NSData *)AES256EncryptWithKey:(NSData *)key;   //加密

- (NSData *)AES256DecryptWithKey:(NSData *)key;   //解密

@end

//

//  AESEncryptAndDecrypt.m

//  NSData扩展方法，用于处理aes加解密

//

//  Created by Vie on 16/4/7.

//  Copyright © 2016年 Vie. All rights reserved.

//

#import "AESEncryptAndDecrypt.h"

#import <CommonCrypto/CommonCryptor.h>

//static char base64[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

@implementation NSData (AES)

- (NSData *)AES256EncryptWithKey:(NSData *)key   //加密

{

//AES256加密，密钥应该是32位的

const void * keyPtr2 = [key bytes];

char (*keyPtr)[32] = keyPtr2;

//对于块加密算法，输出大小总是等于或小于输入大小加上一个块的大小

//所以在下边需要再加上一个块的大小

NSUInteger dataLength = [self length];

size_t bufferSize = dataLength + kCCBlockSizeAES128;

void *buffer = malloc(bufferSize);

size_t numBytesEncrypted = 0;

CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmAES128,

kCCOptionPKCS7Padding/*这里就是刚才说到的PKCS7Padding填充了*/| kCCOptionECBMode,

[key bytes], kCCKeySizeAES256,

NULL,/* 初始化向量(可选) */

[self bytes], dataLength,/*输入*/

buffer, bufferSize,/* 输出 */

&numBytesEncrypted);

if (cryptStatus == kCCSuccess) {

return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];

}

free(buffer);//释放buffer

return nil;

}

- (NSData *)AES256DecryptWithKey:(NSData *)key   //解密

{

//同理，解密中，密钥也是32位的

const void * keyPtr2 = [key bytes];

char (*keyPtr)[32] = keyPtr2;

//对于块加密算法，输出大小总是等于或小于输入大小加上一个块的大小

//所以在下边需要再加上一个块的大小

NSUInteger dataLength = [self length];

size_t bufferSize = dataLength + kCCBlockSizeAES128;

void *buffer = malloc(bufferSize);

size_t numBytesDecrypted = 0;

CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmAES128,

kCCOptionPKCS7Padding/*这里就是刚才说到的PKCS7Padding填充了*/| kCCOptionECBMode,

keyPtr, kCCKeySizeAES256,

NULL,/* 初始化向量(可选) */

[self bytes], dataLength,/* 输入 */

buffer, bufferSize,/* 输出 */

&numBytesDecrypted);

if (cryptStatus == kCCSuccess) {

return [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted];

}

free(buffer);

return nil;

}

@end

//处理base64编码的密钥加密，原文转换为base64字符串;返回aes加密后的base64编码字符串

-(NSString *)encryptBase64Key:(NSString *)key originalText:(NSString *)text{

//base64字符串utf8格式转nsdata

NSData *dataUtf8Key=[[NSData alloc] initWithBase64EncodedString:[NSString stringWithUTF8String:[key UTF8String]] options:NSDataBase64DecodingIgnoreUnknownCharacters];

//原文转data

NSData *textData = [text dataUsingEncoding:NSUTF8StringEncoding];

//aes加密

NSData *cipherData = [textData AES256EncryptWithKey:dataUtf8Key];

//密文转为base64字符串

NSString *cipherBase64Str=[cipherData base64EncodedStringWithOptions:NSDataBase64Encoding64CharacterLineLength];

NSLog(@"密文：%@",cipherBase64Str);

return cipherBase64Str;

}

//处理base64编码的密钥，密文解密；返回原文

-(NSString *)decryptBase64Key:(NSString *)key cipherText:(NSString *)text{

//密钥base64处理

//base64字符串utf8格式转nsdata

NSData *dataUtf8Key=[[NSData alloc] initWithBase64EncodedString:[NSString stringWithUTF8String:[key UTF8String]] options:NSDataBase64DecodingIgnoreUnknownCharacters];

//密文解base64处理

NSData *dataUtf8Data=[[NSData alloc] initWithBase64EncodedString:[NSString stringWithUTF8String:[text UTF8String]] options:NSDataBase64DecodingIgnoreUnknownCharacters];

//解密原文

NSData *decryptData=[dataUtf8Data AES256DecryptWithKey:dataUtf8Key];

NSString *originalText= [[NSString alloc] initWithData:decryptData encoding:NSUTF8StringEncoding];

NSLog(@"原文：%@",originalText);

return originalText;

}

　//测试加密

[self encryptBase64Key:@"74DhItW47MitqIBGOf8aosUllBdhlUxB7es64TKCsgU=" originalText:@"监察局时间长"];

　//测试解密

[self decryptBase64Key:@"74DhItW47MitqIBGOf8aosUllBdhlUxB7es64TKCsgU=" cipherText:@"bWZMFt1I2H7wy25D9V3Ll26IdbOs+/NOlzaEqcUZ9L8="];