If you have access to another computer with a browser. Go to http://www.liquibase.org/download and copy the path to the liquibase zip file. Paste that path onto a wget command as in the example below
wget https://github.com/downloads/liquibase/liquibase/liquibase-2.0.5-bin.zip
unzip the zip file in the location of your choice such as ~/liquibase
Once you are done you will have to manually create your liquibase.properties file.