On Wed, Jan 12, 2022 at 5:14 PM Toke Høiland-Jørgensen <toke@xxxxxxxxxx> wrote: > > [ adding the bpf list - please make sure to include that when sending > BPF-related patches, not everyone in BPF land follows netdev ] > > "Jason A. Donenfeld" <Jason@xxxxxxxxx> writes: > > > BLAKE2s is faster and more secure. SHA-1 has been broken for a long time > > now. This also removes quite a bit of code, and lets us potentially > > remove sha1 from lib, which would further reduce vmlinux size. > > AFAIU, the BPF tag is just used as an opaque (i.e., arbitrary) unique > identifier for BPF programs, without any guarantees of stability. Which > means changing it should be fine; at most we'd confuse some operators > who have memorised the tags of their BPF programs :) > > The only other concern I could see would be if it somehow locked us into > that particular algorithm for other future use cases for computing > hashes of BPF programs (say, signing if that ends up being the direction > we go in). But obviously SHA1 would not be a good fit for that anyway, > so the algorithm choice would have to be part of that discussion in any > case. > > So all in all, I don't see any issues with making this change for BPF. Nack. It's part of api. We cannot change it.
