Am Donnerstag, 12. Januar 2017, 23:53:44 CET schrieb Herbert Xu: Hi Herbert, > > > If we only want to solve that for algif_aead, wouldn't it make more sense > > if the user space caller takes care of that (such as libkcapi)? By > > tinkering with the SGLs and copying the data to the dst buffer before the > > cipher operation takes place, I guess we will add performance degradation > > and more complexity in the kernel. > > > > Having such logic in user space would keep the algif_aead cleaner IMHO. > > We need to have a sane kernel API that respects POSIX. I fully agree. Therefore, I was under the impression that disregarding the AAD in recvmsg entirely would be most appropriate as offered with the patch "crypto: AF_ALG - disregard AAD buffer space for output". In this case we would be fully POSIX compliant, the kernel would not copy the AAD (and thus perform multiple memcpy operations due to copy_from_user and copy_to_user round trips) and leave the AAD copy operation entirely to user space. 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
