使用官方提供的一件安装脚本安装msf，安装时提示msf源仓库里的key验证失败，导致更新不了源
一键安装命令是这样的：
curl https://raw.githubusercontent.com/rapid7/metasploit-omnibus/master/config/templates/metasploit-framework-wrappers/msfupdate.erb > msfinstall && chmod 755 msfinstall && ./msfinstall
报错信息如下：
The repository 'http://downloads.metasploit.com/data/releases/metasploit-framework/apt lucid InRelease' is not signed.
最终通过更新key后，再安装就可以啦！
$ sudo echo 'deb http://apt.metasploit.com/ lucid main' > /etc/apt/sources.list.d/metasploit-framework.list
$ sudo wget -O - http://apt.metasploit.com/metasploit-framework.gpg.key | apt-key add -
$ sudo apt-get update
$ sudo apt-get -y install metasploit-framework