模拟UNIX操作系统登陆，建立用户，修改密码等。-landing simulation of the UNIX operating system, the establishment of users, change passwords.

序列密码--线性反馈移位寄存器--是密码学的基础，密码编程的前部分在这-Cipher- a linear feedback shift register- is based on cryptography, passwords in the first part of programming! !

Sentinel hardware keys dongle memory reader and write passwords bruteforce sources.

基于MD5的密码变换储存的登陆校检demo，登陆密码是经过MD5算法变换后存储于内存中，程序代码中看不到MD5算法变换前的原密码。VS2013编译。-MD5-based password change stored checksum login demo, login passwords are MD5 algorithm after conversion is stored in memory, the program code is not seen in the original pass