d@nny disc@ mc²5d ago

can someone explain why the guy who posted 45 patches to "rewrite the kernel in c++" in 2018 is posting completely insane modifications to crypto/ in his linux-fs tree (edit: this is all on master and i assume it's going in the 7.0 rc) https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit/?h=keys-pqc&id=f3eccecd782dbaf33d5ad0d1fd22ea277300acdb

pkcs7: Allow the signing algo to do whatever digestion it wants itself

Allow the data to be verified in a PKCS#7 or CMS message to be passed
directly to an asymmetric cipher algorithm (e.g. ML-DSA) if it wants to do
whatever passes for hashing/digestion itself. The normal digestion of the
data is then skipped as that would be ignored unless another signed info in
the message has some other algorithm that needs it.

so already this is framing ML-DSA as like doing something extra but the NIST publication indicates that's the job of HashML-DSA

https://nvlpubs.nist.gov/nistpubs/FIPS/NIST.FIPS.204.pdf

this exact fucking guy has an entirely separate "keyutils" repo (he apparently has a patent in this space?) https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/keyutils.git/ no activity for 3 years

Rename ->digest and ->digest_len to ->m and ->m_size to represent the input
to the signature verification algorithm, reflecting that ->digest may no
longer actually *be* a digest.

https://git.kernel.org/pub/scm/linux/kernel/git/dhowells/linux-fs.git/commit/?h=keys-pqc&id=f728074f1f577565c97e465652c3d4afb0964013

diff --git a/crypto/asymmetric_keys/asymmetric_type.c b/crypto/asymmetric_keys/asymmetric_type.c
index 348966ea2175c9..2326743310b1ee 100644
--- a/crypto/asymmetric_keys/asymmetric_type.c
+++ b/crypto/asymmetric_keys/asymmetric_type.c
@@ -593,10 +593,10 @@ static int asymmetric_key_verify_signature(struct kernel_pkey_params *params,
{
struct public_key_signature sig = {
.s_size = params->in2_len,
- .digest_size = params->in_len,
+ .m_size = params->in_len,
.encoding = params->encoding,
.hash_algo = params->hash_algo,
- .digest = (void *)in,
+ .m = (void *)in,
.s = (void *)in2,
};
pkcs7: Allow the signing algo to do whatever digestion it wants itself - kernel/git/dhowells/linux-fs.git - VFS and Filesystem bits

Show threadd@nny disc@ mc²5d ago
i'm gonna have to send an email. this is accepted in 7.0 rc and on my laptop because i pulled master
Show threadd@nny disc@ mc²5d ago
reading the nist doc first. you will never guess that it says "strongly unforgeable" without citation and with no glossary entry. looking it up and "strongly unforgeable" appears to be strictly a thing for module-learning with errors lattice
Show threadd@nny disc@ mc²5d ago

https://eprint.iacr.org/2010/070.pdf

Our construction offers the same efficiency as the “bonsai tree” scheme but supports the stronger notion of strong unforgeability.

hmmmmm sounds fascist

Show threadd@nny disc@ mc²5d ago
bonsai tree definitely sounds tougher. you know they don't choose specially cultured trees for those? that's a real tree and it was made tough and beautiful
Show threadd@nny disc@ mc²5d ago

Over the past several years, there has been steady progress toward building quantum computers. The
security of many commonly used public-key cryptosystems will be at risk if large-scale quantum computers
are ever realized. This would include key-establishment schemes and digital signatures that are based on
integer factorization and discrete logarithms (both over finite fields and elliptic curves).

with you

As a result, in 2016, NIST

you've lost me there

Show threadd@nny disc@ mc²

choose a normal fucking name what's wrong with you

ML-DSA is derived from one of the selected schemes, CRYSTALS-DILITHIUM [5, 6]

Mar 22 at 1:39amWeb
Show threadd@nny disc@ mc²5d ago

well into the foreseeable future, including after the advent of cryptographically relevant quantum computers.

"cryptographically relevant" makes no fucking sense. 25. cmon. a horse can be trained to factor 25

Show threadd@nny disc@ mc²5d ago

destroy:
An action applied to a key or a piece of secret data. After a key or a piece of
secret data is destroyed, no information about its value can be recovered.

Show threadd@nny disc@ mc²5d ago
the definition of digital signature is complete word salad
Show threadd@nny disc@ mc²5d ago

The result of a cryptographic transformation of data that, when properly implemented, provides a mechanism to verify origin authenticity and data integrity and to enforce signatory non-repudiation.

"when properly implemented". psh yeah you can do cryptographic transformation of data, but can you provide a mechanism to verify origin authenticity and data integrity and to enforce signatory non-repudiation?????

Show threadd@nny disc@ mc²5d ago

🚨 fedi entities: NIST has a glossary entry for you

An individual person, organization, device, or process. Used interchangeably with party.

🥳

Show threadd@nny disc@ mc²5d ago
oh my god yes this definition of equivalence
Show threadd@nny disc@ mc²5d ago

Two processes are equivalent if the same output is produced when the same values are input to each process

ok, cool

(either as input parameters, as values made
available during the process, or both).

literally what the fuck

Show threadd@nny disc@ mc²5d ago

A function on bit strings in which the output can be extended to any desired length.

any length. ok

as long as the specified output length is
sufficiently long to prevent trivial attacks

wouldn't really say any

Show threadd@nny disc@ mc²5d ago
oh lmao and they're like "it's one-way", a definition that can only be disproven. collision-resistant: yes it has a meaning. but we're past the c entries. you're too late honey!
Show threadd@nny disc@ mc²5d ago
is a hash value a message digest?
Show threadd@nny disc@ mc²5d ago
a hash value is much broader than a message digest
Show threadd@nny disc@ mc²5d ago
only glossary entry that's a redirect
Show threadd@nny disc@ mc²5d ago
bro they have shall and should in bold. it's so over
Show threadd@nny disc@ mc²5d ago

oh my GOD

trusted third party (TTP)
An entity other than the key pair owner and the verifier that is trusted by the owner, the verifier, or both. Sometimes shortened to “trusted party.”

is it? is it sometimes shortened to that?

Show threadd@nny disc@ mc²5d ago

signature validation
The mathematical verification of the digital signature along with obtaining the appropriate assurances (e.g., public-key validity, private-key possession, etc.).

LMAO literally "the math part plus the government surveillance"

Show threadd@nny disc@ mc²5d ago
tagging the astral engineer who wrote this because pgp keys were not susceptible to his little wehow tutorial on cryptographic surveillance https://blog.yossarian.net/2023/05/21/PGP-signatures-on-PyPI-worse-than-useless
PGP signatures on PyPI: worse than useless

Show threadd@nny disc@ mc²5d ago

PyPI has done everything right, including purposely removing frontend support for PGP years ago.

literally intended to make you think an Event had happened. nope!

Show threadd@nny disc@ mc²5d ago

Type casting. The variable 𝑥 is assigned a value in a set 𝑆 that is constructed from
the value of an expression 𝑦 in a possibly different set 𝑇. The set 𝑇 and the mapping
from 𝑇 to 𝑆 are not explicitly specified, but they should be obvious from the context
in which this statement appears.

this is like. a math notation? "should be obvious from the context" honey no you need to tell me about this hash scheme and shut up

Show threadd@nny disc@ mc²5d ago

The Number Theoretic Transform (NTT) is a specific isomorphism between the rings 𝑅𝑞 and 𝑇𝑞.

that is nippon telephone and teletype

Show threadd@nny disc@ mc²5d ago

The motivation for using NTT is that multiplication is considerably faster in the ring 𝑇𝑞

that's good. i was worried there was any history of ulterior motives for NIST choosing a specific set of parameters to construct a ring

Show threadNosirrahSec 🏴‍☠️ guillotine enthusiast4d ago
@hipsterelectron that's not how people that know what they're doing speak.
Show threadd@nny disc@ mc²4d ago
@NosirrahSec it's INSANE to see the FUCKING CRYPTOGRAPHIC STANDARDS BODY say that. it's WILDLY unprofessional and indicates oh yeah maybe they did succeed in removing the few career staff