Yes, and I think anyone who is reasonably good at math is qualified to do so. I'm not saying I could build undefeatable crypto, mind; I'd have to spend a year brushing up my number theory before I'd make an attempt and I don't fool myself that I'm smarter than the average NSA analyst, so I might well fail.
But if you want proper crypto and are willing to invest some time in it, I'd say take a strong open source algorithm and then rewrite it. Sure, maybe there's backdoors in the compilers, in the chips, maybe they have quantum computers and there's backdoors in the fabric of reality.
My point is not that I know unbeatably secure crypto, but that I have always assumed the NSA was using any and all means available to defeat crypto, and if you ever thought otherwise you were telling yourself fairy stories.
But if you want proper crypto and are willing to invest some time in it, I'd say take a strong open source algorithm and then rewrite it. Sure, maybe there's backdoors in the compilers, in the chips, maybe they have quantum computers and there's backdoors in the fabric of reality.
My point is not that I know unbeatably secure crypto, but that I have always assumed the NSA was using any and all means available to defeat crypto, and if you ever thought otherwise you were telling yourself fairy stories.