Posts
4417
Following
315
Followers
470
Linux kernel hacker and maintainer etc.

OpenPGP: 3AB05486C7752FE1

Jarkko Sakkinen

Edited 1 year ago
I think this is quite good middle ways with enabling HMAC by default: https://lkml.org/lkml/2024/5/21/583

For longer story:
https://lore.kernel.org/linux-integrity/D1FCAPJSYLTS.R9VC1CXDCIHH@kernel.org/

#linux #kernel #tpm #hmac
1
0
0

Jarkko Sakkinen

I’d like to switch A-subkey from RSA to ECDSA one. Do I just send the public key via email to helpdesk@kernel.org?

1
0
1
@Tutanota My email provider is non-profit organization #Kapsi from Oulu, Finland. It is full shell access (SSH) with 50GB of backed up space and 500GB of dump storage (not backed up). And the servers are within the homeland borders :-) It is essentially a full no compromises account. There's also opt-in services like MySQL (not using tho). The whole package costs me 40 EUR per year. Cannot get over how great it is and has been :-) Oulu is the town where IRC protocol was invented by Jarkko Oikarinen in 1988 and the first IRC server ever turned on.
0
0
2

Jarkko Sakkinen

Edited 1 year ago

Took six review rounds to get it but learned something pretty basic about #BuildRoot: pure dependencies should not have Config.ih{.host} at all. In my case the main asset is swtpm, which depends on libtpms. Only swtpm has Config.in.host now and libtpms has only libtpms.{mk,hash}.

0
0
0

Jarkko Sakkinen

Time test packaging Rust program for BuildRoot. Need a full system build for testing a pam module in dev (written in rust).
0
0
0

Jarkko Sakkinen

Edited 1 year ago

Any ways to trace more like bpftrace way between core_initcall and before init starts? Like somehow e.g. compiling eBPF blobs to vmlinux or similar.

I use bootconfig and boot-time tracing stuff and it is nice but barely shadow of what you can do with e.g. bpftrace.

0
0
0

Jarkko Sakkinen

I'm actually sort of wondering this #Gitlab CI thing. I mean it is quite easy to run kselftest even today without any patches to mainline kernel. What's the value added?

#linux #kernel
0
0
0

Jarkko Sakkinen

Made my first post to rust-for-linux list given a pratical need and use. 

I'll make a PoC with asn1rs by simply deleting everything not needed and hammering the rest 🤷 And first in user space and maybe someone with more kernel rust experience can help me out to fit it there.

https://lore.kernel.org/rust-for-linux/D1F44P3VLTBN.30LUQ60X5J3DN@kernel.org/T/#u
0
0
0
The use cases are quite trivial really. Want a server to sign x509 without exposing the private key? Yeah, that's the whole point here. Verification can be done with software, and is done with software. Signing and decryption are done with the private key inside TPM2.

Higher goal is to implement this x509 spec by David Woodhouse but the above is the basic gist here:
https://datatracker.ietf.org/doc/draft-woodhouse-cert-best-practice/
0
0
0

Jarkko Sakkinen

v2 of #TPM2 asymmetric keys: https://lore.kernel.org/linux-integrity/20240521031645.17008-1-jarkko@kernel.org/

Crypto stuff is so easy to break especially in format conversions so decided to save low-hanging fruit clean up for a separate version. From this version forward, I'll promise to stop spamming :-)

#linux #kernel
1
0
0
@securepaul Yeah, not too stressed about that :-) I think I will survive...
0
0
1
@securepaul Good time to activate a bit as I'm on a job seek too. I don't know how to build a great image of myself but I do know how to write code so I guess this is a good approach to move forward ;-)
1
0
1
@securepaul "How did TPM2 began its journey in Linux kernel and where it is heading? Why is TPM2 important for Linux? TPM2 is more like a protocol or contract for hardware cryptography than just a chip. And it still has a legit place despite Trusted Execution Environments (TEEs) and confidential computing up-rise."
1
0
2

Jarkko Sakkinen

Edited 1 year ago
@vathpela Like any modern silicon product have a huge ecosystem of IP blocks bought from various partners. There's even companies that are specialized just doing small parts of SoC's and other products and selling those IP blocks for industry partners. And it is good to have also this ecosystem because it drives tech forward so openness is in my opinion always about finding the right balance :-) All my opinions on almost anything are these middle-ways dull ones 🤷
0
0
0
@vathpela So in principle I do support opening up e.g. ACM's and almost anything really but that said I also get the views of the "other side" :-)
1
0
0
@vathpela Sometimes (not always) the problem with vendor-specific proprietary IP (be it software or hardware) is that sub-parts might be re-licensed from other 3rd parties. So it is not always just an evil corps type of thing but opening IP could be hard to realized sometimes, even if there was will from the company.
1
0
0
@vathpela TPM might be easier because it is vendor neutral standard.
1
0
0

Jarkko Sakkinen

With confidential computing established it might make sense to have a TPM blob in linux-firmware compiled from open source base and way to certify that for distributors.

Most have some form of certificate authority alike thing in place so this would be good use of that.

Then SGX/SNP/TDX could provide a way to establish a sealed device from that and further distribute a vTPM for each virtual machine.
1
0
0
Show older