#include <openssl/evp.h>#include <openssl/rand.h>#include <openssl/rsa.h>/* 常量定義 */EVP_CIPHER_CTX ctx;unsigned char key[EVP_MAX_KEY_LENGTH];unsigned char iv[EVP_MAX_IV_LENGTH];/** key 和隨機數  */struct keys{	unsigned char version[4];//版本	unsigned char key[EVP_MAX_KEY_LENGTH]; //密	unsigned char iv[EVP_MAX_IV_LENGTH];  //隨機數};//生成KEY,并保存在key_file指定的文件中.key_file:路徑+文件名static int load_key(char *key_file);//加密函數data:明文;len:明文長度;out_len:密文長度;返回:密文.static char *des_encrypt(unsigned char *data,int len, int *out_len);//解密data:密文;len:密文長度;out:明文長度;反回明文static char *des_decrypt(unsigned char *data,int len, int *out);