去rarlab官网下载Linux版RAR，如果购买了WinRAR的注册码，相同版本的注册码是可以通用的。
将正版注册文件rarreg.key复制到家目录即可。注意，Linux下的文件名必须使用全小写，否则不能被正确识别。
用RAR压缩解压不会遇到编码问题，并且能够支持与WinRAR完全兼容的分卷和恢复记录等特性。

p7zip-full好像就包含了unrar。

根据官方网站的说明来看：

unrar is a free software version of the non-free unrar utility that exists on many GNU/Linux systems today. It uses the GPL'd UniquE RAR Library by Christian Scheurer and Johannes Winkelmann. This program is a simple command-line front-end to this library, and can list and extract RAR archives. It does not rival the non-free unrar in terms of features, but special care has been taken to ensure it meets most user's needs and it is hoped that GUI archivers such as GNOME's (file-roller) and KDE's ark will use this utility as a back-end.

许可上应该没啥问题

RAR能有今日，拜0day小组使用RAR格式发布海贼版软件所赐。

我去确认下这个问题