On Fri, Jan 13, 2017 at 3:41 PM, Daniel Borkmann <dan...@iogearbox.net> wrote:
> 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.
Unless you want to kill off that vmalloc()+vfree() pair...
--Andy
