Or... you can have a more nuanced viewpoint and note that CBC is really, really, really easy to implement, and _really_ doesn't fall into that category of discussion.
The reason you don't implement your own block ciphers is because side-channel attacks are damn near impossible for normal programmers to understand. Especially timing attacks.
But block-modes of operation? Some of them are really easy. I've ever heard of a bad implementation of CBC causing a security bug.
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I'd say you shouldn't implement your own GCM mode. GCM is quite complex, and the Galois Field's authentication bits could be side-channeled if you don't know what you're doing.
CBC? Where's the flaw? Its so stupid simple I don't think that even a novice would make a critical error.
The reason you don't implement your own block ciphers is because side-channel attacks are damn near impossible for normal programmers to understand. Especially timing attacks.
But block-modes of operation? Some of them are really easy. I've ever heard of a bad implementation of CBC causing a security bug.
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I'd say you shouldn't implement your own GCM mode. GCM is quite complex, and the Galois Field's authentication bits could be side-channeled if you don't know what you're doing.
CBC? Where's the flaw? Its so stupid simple I don't think that even a novice would make a critical error.