python简单的可逆加密程序

简单加密，用python来写写。

 

#coding=utf-8 ''' Description: 可逆的加密与解密 Environment: python2.5.x Author:[e-mail] ''' import os import sys class Code(object): '''可逆的加密与解密''' def __init__(self, key = "[e-mail]"): self.__src_key = key self.__key = self.__get_strascii(self.__src_key, True) def encode(self, value): '''加密函数, 加密后为一串数字''' return "%d" % (self.__get_strascii(value, True) ^ self.__key) def decode(self, pwd): '''解密函数''' if self.is_number(pwd): return self.__get_strascii( (int(pwd)) ^ self.__key, False ) else: print 'require number.' def reset_key(self, key): '''重新设置key''' self.__src_key = key self.__key = self.__get_strascii(self.__src_key, True) #=============================================================================== # 内部调用接口 #=============================================================================== def __get_strascii(self, value, bFlag): if bFlag: return self.__get_str2ascii(value) else: return self.__get_ascii2str(value) def __get_str2ascii(self, value): ls = [] for i in value: ls.append( self.__get_char2ascii( i ) ) return long("".join(ls)) def __get_char2ascii(self, char): '''获取单个字符的acsii码值''' try: return "%03.d" % ord(char) except (TypeError, ValueError): print "key error." exit(1) def __get_ascii2char(self, ascii): if self.is_ascii_range(ascii): return chr(ascii) else: print "ascii error(%d)" % ascii exit(1) def __get_ascii2str(self, n_chars): ls = [] s = "%s" % n_chars n, p = divmod(len(s), 3) if p > 0: nRet = int(s[0 : p]) ls.append( self.__get_ascii2char(nRet)) pTmp = p while pTmp < len(s): ls.append( self.__get_ascii2char( int(s[pTmp: pTmp + 3])) ) pTmp += 3 return "".join(ls) #================================================================================ # 工具接口 #================================================================================ def is_number(self, value): try: int(value) return True except (TypeError, ValueError): pass return False def is_ascii_range(self, n): return 0 <= n < 256 def is_custom_ascii_range(self, n): return 33 <= n <48 or 58 <= n < 126 class Usage(object): ''' 命令行参数读取与解析 ''' def __init__(self): self._clsWork = Code() self._args_dic = {'arg_help' : ['-?', '-help'], 'arg_p' : ['-p', '-pwd'], 'arg_t' : ['-t', '-text'], 'arg_k' : ['-k', '-key'], } def help(self, *k): strHelp = "Usage: pwd [-options] [args...] where option include:" strHelp += """ -? -help print this help message -k <key_str> -p <pwd_str> -k <key_str> -t <text_str>""" print strHelp def args(self, argv_ls): '''dispatch command''' # print argv_ls if len(argv_ls) <= 1 or len(argv_ls) > 5: print 'Unrecognized option' return cmd_dic = {} curr_cmd = '' # control command for i, v in enumerate(argv_ls[1:]): for j in self._args_dic.items(): # add command if v in j[1] and j[0] not in cmd_dic: curr_cmd = j[0] cmd_dic[curr_cmd] = [] break else: # add argv if cmd_dic: cmd_dic[curr_cmd].append(v) # exec command if cmd_dic: self.exec_cmd(cmd_dic) else: print 'Unrecognized option' def exec_cmd(self, cmd_dic): '''exec cmd''' if len(cmd_dic) == 2: if 'arg_p' in cmd_dic and 'arg_k' in cmd_dic/ and len(cmd_dic['arg_p']) == 1 and len(cmd_dic['arg_k']) == 1: self._clsWork.reset_key(cmd_dic['arg_k'][0]) print self._clsWork.encode(cmd_dic['arg_p'][0]) return elif 'arg_t' in cmd_dic and 'arg_k' in cmd_dic/ and len(cmd_dic['arg_t']) == 1 and len(cmd_dic['arg_k']) == 1: self._clsWork.reset_key(cmd_dic['arg_k'][0]) print self._clsWork.decode(cmd_dic['arg_t'][0]) return self.help() if __name__ == '__main__': usage = Usage() usage.args(sys.argv)