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buckle8017

You should take note that this is written by the person that wrote the bad patch.

So grain of salt.

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I've said I'm not sure about the validity of that reasoning.

I've liked it nevertheless for context, as augmentation to parent's post.

I feel like it should be possible to fulfill these advantages with a minimal, not very complex API. I.e. the grandparent's comment about IPsec implementation details doesn't make the cut, but a hardware accelerated cipher implementation does.

A hardware accelerated DMA-capable cipher implementation is an odd thing, and it’s generally not useful on its own. You might want to set up a whole chain of operations (encrypt, checksum, send to network, for example), but I’ve never encountered a case where you actually want to ask an accelerator to asynchronously encrypt application data and return the encrypted data to the application.

Unless you're pushing a ton of extra work into a network-capable accelerator, that sounds exactly like what you'd want for, e.g., an encrypted S3 implementation. You have encryption, RS encoding, striped checksumming, sending fragments to multiple hosts, some sort of potentially interesting partial failure handling, etc.

You could push that all down to the accelerator, but if there are even a few such use cases you might want a dedicated DMA-capable implementation instead.

But is it true or not? Whoever wrote it. (for objective truth the subjects are unimportant)

When you can’t know the objective truth or when there isn’t one (as is the case in making decisions about security tradeoffs in software design), knowing the source of the argument is vital to interpreting its validity.

I disagree 100%. Software security tradeoffs are definitely the sort of thing where you can evaluate arguments on their merits.

It might have been true in 2002 but it hasn't been true since at least about 2010.

You've almost certainly never had a system that supported any hardware accelerated crypto that also required a kernel module.

It's much easier to expose as cpu extensions.

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