In order to access your Github you need to do it via ssh. So you need to add your ssh public key to github. After that you are able to access github via ssh i.e.:

 git init [email protected]:yourname/yourrepo.git


See also: [Github: generating ssh keys][1], [WikiHow][2]

[Edit #1]

For me it's not clear what are you asking for, because you know that installing ca-certificates will fix your problem.


[1]: https://help.github.com/articles/generating-ssh-keys
[2]: http://www.wikihow.com/Add-Ssh-Public-Keys-on-Github