Glenn Greenwald has written a book: No Place to Hide. In it he talks about previously released docs from Snowden, plus he's released a bit more. This article is an excerpt, talking about how the US spy agency *mods* network hardware before it's shipped overseas -- this hardware has the backdoors then that the US repeatedly accused Chinese companies of adding. [That of course doesn't mean the Chinese companies were or are innocent.]
Related articles that *might* interest you as well -- whether you agree with what he published or not, you still might find them interesting:
"Glenn Greenwald: 'I don't trust the UK not to arrest me. Their behaviour has been extreme'"
http://www.theguardian.com/world/2014/may/12/glenn-greenwald-uk-arrest-me-edward-snowden-nsa
"Glenn Greenwald: from Martin Luther King to Anonymous, the state targets dissenters not just "bad guys""
http://www.theguardian.com/world/2014/may/13/glenn-greenwald-anonymous-mass-surveillance-governments-nasa-no-place-to-hide