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Your assumption how backdoors work is very limited/wrong, I am afraid. You assume that you actually understand the code well enough to identify the backdoor -

by janoc 7y ago

Your assumption how backdoors work is very limited/wrong, I am afraid. You assume that you actually understand the code well enough to identify the backdoor - e.g. as some sort of function that will bypass authentication when some secret hardwired password is provided (to give a dumb example). However, to give a real world example of backdoored crypto, it is nothing of the sort. For example, the issue with the potentially backdoored Dual_EC_DRBG pseudorandom number generator has been known since 2004 at least - but the algorithm has been standardized by ISO/NIST and used for years until the potential backdoor issue was widely publicized following the Snowden leaks and the standard was withdrawn. Good luck finding something like that only by reading code unless you are expert in crypto and mathematics. If you were only auditing code whether or not it matches the published, supposedly correct, standard (or algorithm description), you would never find this. The backdoored code was working completely fine, exactly as intended. But the weak random number generator allowed an adversary with sufficient computing resources to break the encryption.

ltbarcly3 7y ago
Yes, it is theoretically possible to create backdoors that are hard or impossible to detect, if you start 20 years ago and subvert the standards used by the entire industry. An improvement in security and privacy isn't limited to "make it impossible, even theoretically, for anything bad to ever happen OR you've accomplished nothing". Most back doors aren't inserted by competent NSA-level actors 20 years in advance. Most are "whenever a message passes through, send a copy to this third party". They are inserted by court order for a specific case due to the government becoming interested late in the game due to a specific case. For example, when terrorists start using some secure email service, the government tries to force the service to allow them to snoop on the relevant conversations. Open sourcing the code would allow you (with the help of the community) to detect these sorts of attempts when the product involves end-to-end encryption. So while having the source and a community auditing changes to that source doesn't prevent every possible attack against your privacy, it prevents almost every one that is plausibly detectable, which is literally as good as you can do.

by janoc 7y ago

ltbarcly3 7y ago

Yes, it is theoretically possible to create backdoors that are hard or impossible to detect, if you start 20 years ago and subvert the standards used by the entire industry. An improvement in security and privacy isn't limited to "make it impossible, even theoretically, for anything bad to ever happen OR you've accomplished nothing". Most back doors aren't inserted by competent NSA-level actors 20 years in advance. Most are "whenever a message passes through, send a copy to this third party". They are inserted by court order for a specific case due to the government becoming interested late in the game due to a specific case. For example, when terrorists start using some secure email service, the government tries to force the service to allow them to snoop on the relevant conversations. Open sourcing the code would allow you (with the help of the community) to detect these sorts of attempts when the product involves end-to-end encryption. So while having the source and a community auditing changes to that source doesn't prevent every possible attack against your privacy, it prevents almost every one that is plausibly detectable, which is literally as good as you can do.