The story does not tell us how Linus Torvalds responded to the NSA, but I’m guessing he told them he wouldn’t be able to inject backdoors even if he wanted to, since the source code is open, and all changes to it are reviewed by many independent people.
Yeah I'm guessing the answer would be more colorful based on the historical data we have
There aren't enough swear-words in the English language, so now I'll have to call you perkeleen vittupää just to express my disgust and frustration with this crap.
Also experience shows that it's possible to backdoor software in very subtle ways that could go years without anyone spotting them. So if he had decided to he probably could have done it, despite Linux being open source.
Years ago there was a commit to the Linux kernal that strangly had no author. This got some attention of several of the developers.
Looking into the code that had to deal with network transmission. there was a section that if you tried to get network access in a unusual way had a check that was written something like this.
If (usr_permission = ROOT) ...
Instead of
If (usr_permission == ROOT) ...
The first giving the user root if invoked and the second checking to see if the user was root.
It's widely thought this was the NSA or some other intelligence agency trying to backdoor lin Linux.
This is because NSA has two roles: eavesdropping on foreign adversaries, and protecting our internal systems from adversaries. Under the first role, they might introduce an exploit known only to themselves. Under the second, they help protect US systems from exploits known to others.
Notably this was in 2003 before git (2005) so linux source was in a central bitkeeper repo. So a commit with no associated data about who did it should not have been possible.
Circa 1975, IBM proposed the cipher now called DES, the Data Encryption Standard. It became a worldwide standard for secret key encryption. As IBM originally designed it, DES had a 64-bit key. The National Security Agency (NSA) required that the key be reduced from 64 bits to 56 bits, with the other 8 bits used as a checksum.
This made no sense. If a checksum were really needed, then the key could be increased from 64 to 72 bits. It was widely believed that the real reason the NSA made this demand was that it knew how to crack messages using a 56-bit key, but not messages using a 64-bit key. This proved to be true.
A OS backdoor is very simular to a backdoor cut, which allows a player to sneak behind defenders when they are focused on the ball or player with a ball.
NBA coaches have taken inspiration from many different places to perfect their plays. Computer security is just another step.