Am Dienstag, 24. November 2015, 12:54:07 schrieb Phil Sutter: Hi Phil, > >There "still" are dedicated crypto engines out there which need a driver >to be accessed, so using them from userspace is not as simple as with >padlock or AESNI. This was the reasoning behind the various cryptodev >implementations and af_alg. Using those to establish a TLS connection >with OpenSSL means to fetch encrypted data to userspace first and then >feed it to the kernel again for decryption. Using cryptodev-linux, this >will be zero-copy, but still there's an additional context switch >involved which the approach here avoids. Well, when being nasty, I could ask, why not putting the entire web server into the kernel. Heck, why not getting rid of user space? Sorry, I could not resist. :-) But back to the technical discussion. My main concern is that TLS is a big protocol and it is by far not the only crypto protocol where all those protocols seem to uses the same crypto primitives. And to me, there should be a good reason why software executes in supervisor state. Simply saving some context switches is not a good argument, because the context switches are there for a reason: to keep the system safe and secure. Ciao Stephan -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
