////  YXCrypto.h//  用秘钥给字符串加密或者解密////  Created by YouXian on 14-11-16.//  Copyright (c) 2014年 YouXian. All rights reserved.//#import <Foundation/Foundation.h>@interface YXCrypto : NSObject/*! * 给字符串加密 */+ (NSString *)DesEncryptString:(NSString*)src WithKey:(NSString *)key;/*! * 给字符串解密 */+ (NSString *)DesDecryptString:(NSString*)src WithKey:(NSString *)key;@end

////  YXCrypto.m//  用秘钥给字符串加密或者解密////  Created by YouXian on 14-11-16.//  Copyright (c) 2014年 YouXian. All rights reserved.//#import "YXCrypto.h"#import <CommonCrypto/CommonCryptor.h>#if __has_feature(objc_arc)// ARC#define Auto_Release(obj)#define Safe_Release(obj)#else// 非ARC#define Auto_Release(obj) [obj autorelease]#define Safe_Release(obj) [obj release]; obj = nil#endifstatic YXCrypto *shareInstance = nil;@implementation YXCrypto/*! * 给字符串加密 */+ (NSString *)DesEncryptString:(NSString*)src WithKey:(NSString *)key {    NSString* strRet = @"";        if (shareInstance == nil)    {        shareInstance = [[YXCrypto alloc] init];    }        // encrypt source content    NSData* bytes = [src dataUsingEncoding:NSUTF8StringEncoding];    NSData* data =http://www.mamicode.com/ [shareInstance DesCryptWithOperation:kCCEncrypt                                                  bytes:bytes                                                    key:key];        // format bytes to visible string    char* pBuff = (char*)[data bytes];    for (int i=0; i<data.length; i++) {        strRet = [strRet stringByAppendingFormat:@"%02X", pBuff[i]& 0xFF];    }    return strRet;}/*! * 给字符串解密 */+ (NSString *)DesDecryptString:(NSString*)src WithKey:(NSString *)key{    if (shareInstance == nil)    {        shareInstance = [[YXCrypto alloc] init];    }        static unsigned char _map_ch2hex[] =    {        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09,        0, 0, 0, 0, 0, 0, 0,    // :, ;, <, =, >, ?, @,        0x0A, 0x0B, 0x0C, 0x0D, 0x0E, 0x0F,    };        // decode source content to bytes    unsigned char* bytes = (unsigned char*)malloc((src.length+1)*sizeof(unsigned char));    [[src uppercaseString] getCString:(char*)bytes maxLength:src.length+1 encoding:NSUTF8StringEncoding];    unsigned char *p1 = bytes, *p2 = bytes;    unsigned long n = src.length/2;    for (int i=0; i<n; i++) {        *p1 = _map_ch2hex[*p2-‘0‘] * 0x10 + _map_ch2hex[*(p2+1)-‘0‘];        p1++;        p2+=2;    }    NSData* data =http://www.mamicode.com/ [NSData dataWithBytes:bytes                                  length:n];        // decrypt source bytes    NSData* dataOut = [shareInstance DesCryptWithOperation:kCCDecrypt                                                     bytes:data                                                       key:key];    free(bytes);        NSString* strRet = [[NSString alloc] initWithData:dataOut                                             encoding:NSUTF8StringEncoding];    Auto_Release(strRet);        return strRet;}- (NSData *)DesCryptWithOperation:(CCOperation)operation bytes:(NSData*)bytes key:(NSString *)key {        NSUInteger dataLength = [bytes length];        size_t bufferSize = ([bytes length] + kCCBlockSizeDES) & ~(kCCBlockSizeDES - 1);    unsigned char *buffer = (unsigned char *)malloc(bufferSize*sizeof(unsigned char));    memset((void*)buffer, 0, bufferSize);        size_t numBytesCrypted = 0;    CCCryptorStatus cryptStatus = CCCrypt(operation,                                          kCCAlgorithmDES,                                          kCCOptionPKCS7Padding | kCCOptionECBMode,                                          (void const*)[key UTF8String],                                          kCCKeySizeDES,                                          NULL,                                          [bytes bytes], dataLength,                                          (void*)buffer, bufferSize,                                          &numBytesCrypted);    NSData* dataRet = nil;    if (cryptStatus == kCCSuccess) {        dataRet = [[NSData alloc] initWithBytes:buffer length:numBytesCrypted];        Auto_Release(dataRet);    }    free(buffer);    return dataRet;}@end