加密这种事，现在很常用。但是如何不易被被人破解就要下功夫。
普通网上的des3加密，其实比较容易被别人强行爆破出，但是如果密钥也是动态生成的话就比较方便。（通过自己的密码本来随机创建加密解密）。
我现在先附上普通的des加密，这个是借鉴与其他地方，侵删。
DES简介：
DES全称为Data Encryption Standard，即数据加密标准，是一种使用密钥加密的块算法， 算法的入口参数有三个:Key、Data、Mode。
Key：为7个字节共56位,是DES算法的工作密钥;
Data：为8个字节64位,是要被加密或被解密的数据;
Mode：为DES的工作方式,有两种:加密或解密。
3DES简介：
3DES（或称为Triple DES）是三重数据加密算法（TDEA，Triple Data Encryption Algorithm）块密码的通称。它相当于是对每个数据块应用三次DES加密算法。由于计算机运算能力的增强，原版DES密码的密钥长度变得容易被暴力破解；3DES即是设计用来提供一种相对简单的方法，即通过增加DES的密钥长度来避免类似的攻击，而不是设计一种全新的块密码算法。因此比起最初的DES，3DES更为安全。
加密实例：
java版
package com.v1.linxun.portal.utils;
import java.security.Key;
import javax.crypto.Cipher;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESedeKeySpec;
import javax.crypto.spec.IvParameterSpec;
/**
* 3DES加密工具类
*/
public class Des3Util {
// 密钥 长度不得小于24
private final static String secretKey = "123456789012345678901234" ;
// 向量 可有可无 终端后台也要约定
private final static String iv = "01234567";
// 加解密统一使用的编码方式
private final static String encoding = "utf-8";
/**
* 3DES加密
*
* @param plainText
* 普通文本
* @return
* @throws Exception
*/
public static String encode(String plainText) throws Exception {
Key deskey = null;
DESedeKeySpec spec = new DESedeKeySpec(secretKey .getBytes());
SecretKeyFactory keyfactory = SecretKeyFactory.getInstance( "desede");
deskey = keyfactory.generateSecret( spec);
Cipher cipher = Cipher.getInstance( "desede/CBC/PKCS5Padding");
IvParameterSpec ips = new IvParameterSpec( iv.getBytes());
cipher.init(Cipher. ENCRYPT_MODE, deskey, ips);
byte[] encryptData = cipher.doFinal( plainText.getBytes( encoding));
return Base64. encode( encryptData);
}
/**
* 3DES解密
*
* @param encryptText
* 加密文本
* @return
* @throws Exception
*/
public static String decode(String encryptText) throws Exception {
Key deskey = null;
DESedeKeySpec spec = new DESedeKeySpec( secretKey.getBytes());
SecretKeyFactory keyfactory = SecretKeyFactory.getInstance( "desede");
deskey = keyfactory. generateSecret( spec);
Cipher cipher = Cipher.getInstance( "desede/CBC/PKCS5Padding" );
IvParameterSpec ips = new IvParameterSpec( iv.getBytes());
cipher. init(Cipher. DECRYPT_MODE, deskey, ips);
byte[] decryptData = cipher. doFinal(Base64. decode(encryptText ));
return new String( decryptData, encoding);
}
public static void main(String args[]) throws Exception{
String str = "你好" ;
System. out.println( "----加密前-----：" + str );
String encodeStr = Des3Util. encode( str);
System. out.println( "----加密后-----：" + encodeStr );
System. out.println( "----解密后-----：" + Des3Util.decode( encodeStr));
}
}
Android版：
package com.inn.test;
import java.security.Key;
import javax.crypto.Cipher;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.DESedeKeySpec;
import javax.crypto.spec.IvParameterSpec;
import android.util.Base64;
/**
* Android 3DES加密工具类
*/
public class AndroidDes3Util {
// 密钥 长度不得小于24
private final static String secretKey = "123456789012345678901234" ;
// 向量 可有可无 终端后台也要约定
private final static String iv = "01234567" ;
// 加解密统一使用的编码方式
private final static String encoding = "utf-8" ;
/**
* 3DES加密
*
* @param plainText
* 普通文本
* @return
* @throws Exception
*/
public static String encode(String plainText) throws Exception {
Key deskey = null ;
DESedeKeySpec spec = new DESedeKeySpec(secretKey .getBytes());
SecretKeyFactory keyfactory = SecretKeyFactory.getInstance( "desede");
deskey = keyfactory.generateSecret(spec);
Cipher cipher = Cipher.getInstance( "desede/CBC/PKCS5Padding");
IvParameterSpec ips = new IvParameterSpec( iv.getBytes());
cipher.init(Cipher. ENCRYPT_MODE , deskey, ips);
byte [] encryptData = cipher.doFinal(plainText.getBytes(encoding ));
return Base64.encodeToString(encryptData,Base64. DEFAULT );
}
/**
* 3DES解密
*
* @param encryptText
* 加密文本
* @return
* @throws Exception
*/
public static String decode(String encryptText) throws Exception {
Key deskey = null ;
DESedeKeySpec spec = new DESedeKeySpec( secretKey.getBytes());
SecretKeyFactory keyfactory = SecretKeyFactory.getInstance( "desede" );
deskey = keyfactory. generateSecret(spec);
Cipher cipher = Cipher.getInstance( "desede/CBC/PKCS5Padding" );
IvParameterSpec ips = new IvParameterSpec( iv.getBytes());
cipher. init(Cipher. DECRYPT_MODE, deskey, ips);
byte [] decryptData = cipher.doFinal(Base64. decode(encryptText, Base64. DEFAULT));
return new String (decryptData, encoding);
}
}
IOS版：
//
// DES3EncryptUtil.h
// DES3加解密工具
//
// Created by xc on 15/12/18.
// Copyright © 2015年 xc. All rights reserved.
//
#import <Foundation/Foundation.h>
@interface DES3EncryptUtil : NSObject
// 加密方法
+ (NSString*)encrypt:(NSString*)plainText;
// 解密方法
+ (NSString*)decrypt:(NSString*)encryptText;
@end
//
// DES3EncryptUtil.m
// DES3加解密工具
// Created by xc on 15/12/18.
// Copyright © 2015年 xc. All rights reserved.
#import <Foundation/Foundation.h>
#import <CommonCrypto/CommonCryptor.h>
#import "MyBase64.h"
//秘钥
#define gkey @"xiangchao@qq.comrnnchina"
//向量
#define gIv @"01234567"
@implementation DES3EncryptUtil : NSObject
// 加密方法
+ (NSString*)encrypt:(NSString*)plainText {
NSData* data = [plainText dataUsingEncoding:NSUTF8StringEncoding];
size_t plainTextBufferSize = [data length];
const void *vplainText = (const void *)[data bytes];
CCCryptorStatus ccStatus;
uint8_t *bufferPtr = NULL;
size_t bufferPtrSize = 0;
size_t movedBytes = 0;
bufferPtrSize = (plainTextBufferSize + kCCBlockSize3DES) & ~(kCCBlockSize3DES - 1);
bufferPtr = malloc( bufferPtrSize * sizeof(uint8_t));
memset((void *)bufferPtr, 0x0, bufferPtrSize);
const void *vkey = (const void *) [gkey UTF8String];
const void *vinitVec = (const void *) [gIv UTF8String];
ccStatus = CCCrypt(kCCEncrypt,
kCCAlgorithm3DES,
kCCOptionPKCS7Padding,
vkey,
kCCKeySize3DES,
vinitVec,
vplainText,
plainTextBufferSize,
(void *)bufferPtr,
bufferPtrSize,
&movedBytes);
NSData *myData = [NSData dataWithBytes:(const void *)bufferPtr length:(NSUInteger)movedBytes];
NSString *result = [MyBase64 base64EncodedStringFrom:myData];
return result;
}
// 解密方法
+ (NSString*)decrypt:(NSString*)encryptText {
NSData *encryptData = [MyBase64 dataWithBase64EncodedString:encryptText];
size_t plainTextBufferSize = [encryptData length];
const void *vplainText = [encryptData bytes];
CCCryptorStatus ccStatus;
uint8_t *bufferPtr = NULL;
size_t bufferPtrSize = 0;
size_t movedBytes = 0;
bufferPtrSize = (plainTextBufferSize + kCCBlockSize3DES) & ~(kCCBlockSize3DES - 1);
bufferPtr = malloc( bufferPtrSize * sizeof(uint8_t));
memset((void *)bufferPtr, 0x0, bufferPtrSize);
const void *vkey = (const void *) [gkey UTF8String];
const void *vinitVec = (const void *) [gIv UTF8String];
ccStatus = CCCrypt(kCCDecrypt,
kCCAlgorithm3DES,
kCCOptionPKCS7Padding,
vkey,
kCCKeySize3DES,
vinitVec,
vplainText,
plainTextBufferSize,
(void *)bufferPtr,
bufferPtrSize,
&movedBytes);
NSString *result = [[NSString alloc] initWithData:[NSData dataWithBytes:(const void *)bufferPtr
length:(NSUInteger)movedBytes] encoding:NSUTF8StringEncoding] ;
return result;
}
@end
IOS加密工具中会将加密后的密文 转化程Base64的字符串，用到了Base64编码工具，如下
//
// CommonFunc.h
// PRJ_base64
//
// Created by wangzhipeng on 12-11-29.
// Copyright (c) 2012年 com.comsoft. All rights reserved.
//
#import <Foundation/Foundation.h>
#define __BASE64( text ) [CommonFunc base64StringFromText:text]
#define __TEXT( base64 ) [CommonFunc textFromBase64String:base64]
@interface MyBase64 : NSObject
/******************************************************************************
函数名称 : + (NSString *)base64StringFromText:(NSString *)text
函数描述 : 将文本转换为base64格式字符串
输入参数 : (NSString *)text 文本
输出参数 : N/A
返回参数 : (NSString *) base64格式字符串
备注信息 :
******************************************************************************/
+ (NSString *)base64StringFromText:(NSString *)text;
/******************************************************************************
函数名称 : + (NSString *)base64StringFromText:(NSString *)text
函数描述 : 将文本转换为base64格式字符串
输入参数 : (NSString *)text 文本
输出参数 : N/A
返回参数 : (NSString *) base64格式字符串
备注信息 :
******************************************************************************/
+ (NSString *)base64EncodedStringFrom:(NSData *)data;
/******************************************************************************
函数名称 : + (NSString *)textFromBase64String:(NSString *)base64
函数描述 : 将base64格式字符串转换为文本
输入参数 : (NSString *)base64 base64格式字符串
输出参数 : N/A
返回参数 : (NSString *) 文本
备注信息 :
******************************************************************************/
+ (NSString *)textFromBase64String:(NSString *)base64;
/******************************************************************************
函数名称 : + (NSString *)textFromBase64String:(NSString *)base64
函数描述 : 将base64格式字符串转换为文本
输入参数 : (NSString *)base64 base64格式字符串
输出参数 : N/A
返回参数 : (NSString *) 文本
备注信息 :
******************************************************************************/
+ (NSData *)dataWithBase64EncodedString:(NSString *)string;
@end
//
// CommonFunc.m
// PRJ_base64
//
// Created by wangzhipeng on 12-11-29.
// Copyright (c) 2012年 com.comsoft. All rights reserved.
//
#import "MyBase64.h"
//引入IOS自带密码库
#import <CommonCrypto/CommonCryptor.h>
//空字符串
#define LocalStr_None @""
static const char encodingTable[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
@implementation MyBase64 : NSObject
+ (NSString *)base64StringFromText:(NSString *)text
{
if (text && ![text isEqualToString:LocalStr_None]) {
//取项目的bundleIdentifier作为KEY 改动了此处
//NSString *key = [[NSBundle mainBundle] bundleIdentifier];
NSData *data = [text dataUsingEncoding:NSUTF8StringEncoding];
//IOS 自带DES加密 Begin 改动了此处
//data = [self DESEncrypt:data WithKey:key];
//IOS 自带DES加密 End
return [self base64EncodedStringFrom:data];
}
else {
return LocalStr_None;
}
}
+ (NSString *)textFromBase64String:(NSString *)base64
{
if (base64 && ![base64 isEqualToString:LocalStr_None]) {
//取项目的bundleIdentifier作为KEY 改动了此处
//NSString *key = [[NSBundle mainBundle] bundleIdentifier];
NSData *data = [self dataWithBase64EncodedString:base64];
//IOS 自带DES解密 Begin 改动了此处
//data = [self DESDecrypt:data WithKey:key];
//IOS 自带DES加密 End
return [[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding];
}
else {
return LocalStr_None;
}
}
/******************************************************************************
函数名称 : + (NSData *)DESEncrypt:(NSData *)data WithKey:(NSString *)key
函数描述 : 文本数据进行DES加密
输入参数 : (NSData *)data
(NSString *)key
输出参数 : N/A
返回参数 : (NSData *)
备注信息 : 此函数不可用于过长文本
******************************************************************************/
+ (NSData *)DESEncrypt:(NSData *)data WithKey:(NSString *)key
{
char keyPtr[kCCKeySizeAES256+1];
bzero(keyPtr, sizeof(keyPtr));
[key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];
NSUInteger dataLength = [data length];
size_t bufferSize = dataLength + kCCBlockSizeAES128;
void *buffer = malloc(bufferSize);
size_t numBytesEncrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmDES,
kCCOptionPKCS7Padding | kCCOptionECBMode,
keyPtr, kCCBlockSizeDES,
NULL,
[data bytes], dataLength,
buffer, bufferSize,
&numBytesEncrypted);
if (cryptStatus == kCCSuccess) {
return [NSData dataWithBytesNoCopy:buffer length:numBytesEncrypted];
}
free(buffer);
return nil;
}
/******************************************************************************
函数名称 : + (NSData *)DESEncrypt:(NSData *)data WithKey:(NSString *)key
函数描述 : 文本数据进行DES解密
输入参数 : (NSData *)data
(NSString *)key
输出参数 : N/A
返回参数 : (NSData *)
备注信息 : 此函数不可用于过长文本
******************************************************************************/
+ (NSData *)DESDecrypt:(NSData *)data WithKey:(NSString *)key
{
char keyPtr[kCCKeySizeAES256+1];
bzero(keyPtr, sizeof(keyPtr));
[key getCString:keyPtr maxLength:sizeof(keyPtr) encoding:NSUTF8StringEncoding];
NSUInteger dataLength = [data length];
size_t bufferSize = dataLength + kCCBlockSizeAES128;
void *buffer = malloc(bufferSize);
size_t numBytesDecrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt, kCCAlgorithmDES,
kCCOptionPKCS7Padding | kCCOptionECBMode,
keyPtr, kCCBlockSizeDES,
NULL,
[data bytes], dataLength,
buffer, bufferSize,
&numBytesDecrypted);
if (cryptStatus == kCCSuccess) {
return [NSData dataWithBytesNoCopy:buffer length:numBytesDecrypted];
}
free(buffer);
return nil;
}
/******************************************************************************
函数名称 : + (NSData *)dataWithBase64EncodedString:(NSString *)string
函数描述 : base64格式字符串转换为文本数据
输入参数 : (NSString *)string
输出参数 : N/A
返回参数 : (NSData *)
备注信息 :
******************************************************************************/
+ (NSData *)dataWithBase64EncodedString:(NSString *)string
{
if (string == nil)
[NSException raise:NSInvalidArgumentException format:nil];
if ([string length] == 0)
return [NSData data];
static char *decodingTable = NULL;
if (decodingTable == NULL)
{
decodingTable = malloc(256);
if (decodingTable == NULL)
return nil;
memset(decodingTable, CHAR_MAX, 256);
NSUInteger i;
for (i = 0; i < 64; i++)
decodingTable[(short)encodingTable[i]] = i;
}
const char *characters = [string cStringUsingEncoding:NSASCIIStringEncoding];
if (characters == NULL) // Not an ASCII string!
return nil;
char *bytes = malloc((([string length] + 3) / 4) * 3);
if (bytes == NULL)
return nil;
NSUInteger length = 0;
NSUInteger i = 0;
while (YES)
{
char buffer[4];
short bufferLength;
for (bufferLength = 0; bufferLength < 4; i++)
{
if (characters[i] == '\0')
break;
if (isspace(characters[i]) || characters[i] == '=')
continue;
buffer[bufferLength] = decodingTable[(short)characters[i]];
if (buffer[bufferLength++] == CHAR_MAX) // Illegal character!
{
free(bytes);
return nil;
}
}
if (bufferLength == 0)
break;
if (bufferLength == 1) // At least two characters are needed to produce one byte!
{
free(bytes);
return nil;
}
// Decode the characters in the buffer to bytes.
bytes[length++] = (buffer[0] << 2) | (buffer[1] >> 4);
if (bufferLength > 2)
bytes[length++] = (buffer[1] << 4) | (buffer[2] >> 2);
if (bufferLength > 3)
bytes[length++] = (buffer[2] << 6) | buffer[3];
}
bytes = realloc(bytes, length);
return [NSData dataWithBytesNoCopy:bytes length:length];
}
/******************************************************************************
函数名称 : + (NSString *)base64EncodedStringFrom:(NSData *)data
函数描述 : 文本数据转换为base64格式字符串
输入参数 : (NSData *)data
输出参数 : N/A
返回参数 : (NSString *)
备注信息 :
******************************************************************************/
+ (NSString *)base64EncodedStringFrom:(NSData *)data
{
if ([data length] == 0)
return @"";
char *characters = malloc((([data length] + 2) / 3) * 4);
if (characters == NULL)
return nil;
NSUInteger length = 0;
NSUInteger i = 0;
while (i < [data length])
{
char buffer[3] = {0,0,0};
short bufferLength = 0;
while (bufferLength < 3 && i < [data length])
buffer[bufferLength++] = ((char *)[data bytes])[i++];
// Encode the bytes in the buffer to four characters, including padding "=" characters if necessary.
characters[length++] = encodingTable[(buffer[0] & 0xFC) >> 2];
characters[length++] = encodingTable[((buffer[0] & 0x03) << 4) | ((buffer[1] & 0xF0) >> 4)];
if (bufferLength > 1)
characters[length++] = encodingTable[((buffer[1] & 0x0F) << 2) | ((buffer[2] & 0xC0) >> 6)];
else characters[length++] = '=';
if (bufferLength > 2)
characters[length++] = encodingTable[buffer[2] & 0x3F];
else characters[length++] = '=';
}
return [[NSString alloc] initWithBytesNoCopy:characters length:length encoding:NSASCIIStringEncoding freeWhenDone:YES];
}
@end
