這裏使用框架提供的des加解密庫： 首先引入頭文件 #import <CommonCrypto/CommonCryptor.h>
主要的加解密函數如下:
/*字符串加密
*參數
*plainText : 加密明文
*key : 密鑰 64位
*/
+ (NSString *) encryptUseDES:(NSString *)plainText key:(NSString *)key
{
NSString *ciphertext = nil;
const char *textBytes = [plainText UTF8String];
NSUInteger dataLength = [plainText length];
unsigned char buffer[1024];
memset(buffer, 0, sizeof(char));
Byte iv[] = {1,2,3,4,5,6,7,8};
size_t numBytesEncrypted = 0;
CCCryptorStatus cryptStatus = CCCrypt(kCCEncrypt, kCCAlgorithmDES,
kCCOptionPKCS7Padding,
[key UTF8String], kCCKeySizeDES,
iv,
textBytes, dataLength,
buffer, 1024,
&numBytesEncrypted);
if (cryptStatus == kCCSuccess) {
NSData *data = [NSData dataWithBytes:buffer length:(NSUInteger)numBytesEncrypted];
ciphertext = [[[NSString alloc] initWithData:[GTMBase64 encodeData:data] encoding:NSUTF8StringEncoding] autorelease];
}
return ciphertext;
}
//解密
+ (NSString *) decryptUseDES:(NSString*)cipherText key:(NSString*)key
{
NSData* cipherData = [GTMBase64 decodeString:cipherText];
unsigned char buffer[1024];
memset(buffer, 0, sizeof(char));
size_t numBytesDecrypted = 0;
Byte iv[] = {1,2,3,4,5,6,7,8};
CCCryptorStatus cryptStatus = CCCrypt(kCCDecrypt,
kCCAlgorithmDES,
kCCOptionPKCS7Padding,
[key UTF8String],
kCCKeySizeDES,
iv,
[cipherData bytes],
[cipherData length],
buffer,
1024,
&numBytesDecrypted);
NSString* plainText = nil;
if (cryptStatus == kCCSuccess) {
NSData* data = [NSData dataWithBytes:buffer length:(NSUInteger)numBytesDecrypted];
plainText = [[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding] autorelease];
}
return plainText;
}
