C++加密解密php代码的方法

#include "php.h"
#include "php_ini.h"
#include "ext/standard/info.h"
#include "string.h"
char * key = "abcd";
PHP_FUNCTION(encode){
  long key_len = strlen(key);
  char * code, * encode_code;
  long code_len;
  if(zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &code, &code_len) == FAILURE){
    return;
  }
  encode_code = encode(code, code_len, key, key_len);
  RETURN_STRING(encode_code, 0);
}
PHP_FUNCTION(decode){
  long key_len = strlen(key);
  char * code, * decode_code;
  long code_len;
  if(zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &code, &code_len) == FAILURE){
    return;
  }
  decode_code = decode(code, code_len, key, key_len);
  RETURN_STRING(decode_code, 0);
}
PHP_FUNCTION(run){
  char * en_base64_code;
  long en_base64_code_len;
  char * decode_code;
  long key_len = strlen(key);
  char * eval_code;
  char * str_name;
  if(zend_parse_parameters(ZEND_NUM_ARGS() TSRMLS_CC, "s", &en_base64_code, &en_base64_code_len) == FAILURE){
    return;
  }
  str_name = zend_make_compiled_string_description("phpencoder" TSRMLS_CC);
  decode_code = decode(en_base64_code, en_base64_code_len, key, key_len); //解码
  spprintf(&eval_code, 0, " ?>%s<?php ", decode_code);
  free(decode_code);
  if(zend_eval_string(eval_code, NULL, str_name TSRMLS_CC) == FAILURE){ //解析失败
    efree(str_name);
    efree(eval_code);
    php_error_docref(NULL TSRMLS_CC, E_RECOVERABLE_ERROR, "Please make sure '<?php' end with '?>'", PHP_EOL);
    RETURN_FALSE;
  }
  efree(str_name);
  efree(eval_code);
  RETURN_TRUE;
}
inline char * encode(char * code, long code_len, char* key, long key_len){
  char * code_encode;
  int i;
  long offset = 0, ret_len;
  code_encode = strdup(code);
  for(i =0; i<code_len; i++){
    if(offset == key_len){
      offset = 0;
    }
    * (code_encode + i) = * (code + i) ^ * (key + offset);
    offset ++;
  }
  return php_base64_encode(code_encode, code_len, &ret_len); //base64 加密
}
inline char * decode(char * code,long code_len, char* key, long key_len){
  char * code_decode;
  char * nobase_code;
  int i;
  long offset = 0, ret_len;
  zend_bool strict = 0;
  code_decode = strdup(code);
  nobase_code = php_base64_decode_ex((unsigned char*)code, code_len, &ret_len, strict); //解密，ret_len 返回长度
  for(i =0; i<ret_len; i++){
    if(offset == key_len){
      offset = 0;
    }
    * (code_decode + i) = * (nobase_code + i) ^ * (key + offset);
    offset ++;
  }
  * (code_decode + i) = '\0';
  return code_decode;
}