On 01/14/2017 12:16 AM, Andy Lutomirski wrote:
On Fri, Jan 13, 2017 at 2:38 PM, Daniel Borkmann <dan...@iogearbox.net> wrote:Commit 7bd509e311f4 ("bpf: add prog_digest and expose it via fdinfo/netlink") was recently discussed, partially due to admittedly suboptimal name of "prog_digest" in combination with sha1 hash usage, thus inevitably and rightfully concerns about its security in terms of collision resistance were raised with regards to use-cases.Seems reasonable. My only question is whether you'd still want to switch to SHA-256 just from a code cleanliness perspective. With SHA-256 you can use the easy streaming API I wrote, but with SHA-1 you're still stuck with the crappy API in lib/, and I'm not volunteering to fix up the SHA-1 API.
We'd need to truncate that in kernel anyway to not get a too long tag, so given that I'm actually fine with it as-is. I was planning to submit the code for testing to bpf selftests for net-next once it's merged back, too. Thanks, Daniel
