i still don't get why people use elliptic curves instead of diffie-hellman since you can use it for public keys too. the index calculus cryptanalytic method appears to apply for the usage of F_q where q = pn for some prime p. it appears that if q is a large prime and q - 1 is divisible by a large prime, that covers the two biggest error cases
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wow https://www-ee.stanford.edu/~hellman/publications/27.pdf didn't know diffie and hellman also said DES was brute-forceable like a year after it was standardized???
The cryptosystem is a FIPS (Federal Information Processing Standard) standard. binding on all applicable federal agencies. Because ASCII is also a FIPS standard, the plaintext data will often be represented as 8-bit ASCII characters.
there's everything there's IBM there's FIPS there's even NIST by its old name
In summary, we believe we have made a convincing argument concerning the insecurity and planned obsolescence inherent in the proposed cryptostandard.
planned obsolescence in 1977?????
https://en.wikipedia.org/wiki/Advanced_Encryption_Standard a paper in 2015 has space complexity of cracking AES-128 down to 9 exabytes
https://en.wikipedia.org/wiki/Exascale_computing
On 29 July 2015, Barack Obama signed an executive order creating a National Strategic Computing Initiative calling for the accelerated development of an exascale system and funding research into post-semiconductor computing.[32]
This attack requires the attacker to be able to run programs on the same system or platform that is performing AES.
the way they dance around the subject of how "side channels" work while glazing up known evil bad guys like djb and shamir is crazy. it's not about "running programs" on the same system, but those programs being able to trigger cryptographic operations in response to uncontrolled input
it's so crazy that AES and block ciphers more generally don't mix up ciphertext across blocks??????
i'm pretty sure that's correct????
ChaCha is the basis of the BLAKE hash function, a finalist in the NIST hash function competition, and its faster successors BLAKE2 and BLAKE3.
finally this all makes sense to me
learning about checksums. i don't like em
MD5 was designed by Ronald Rivest in 1991
does this guy literally do anything other than backdoors
There is a long list of cryptographic hash functions but many have been found to be vulnerable and should not be used.
i'm fucking amazed nobody has ever brought up the idea that checksums might be different for the purpose of integrity checking vs cryptographic signatures
@hipsterelectron
For the purpose of an integrity check it would actually be great if the checksum differences only slightly is the change in data is small
@realn2s i was thinking about this with i believe @heptapodEnthusiast and we were both kind of unsure how to achieve collision resistance without indifferentiability but i am pretty sure i figured out a cheat code for this and it is basically to retain the entire tree of hash computations at all times, and then invent a tree hash for directory trees:
for file hashes, use a tree hash like BLAKE3 (i'm making some tiny changes personally) and just retain the entire hash computation tree. this will take something like
C * log^2 nspace forC= chunk size andn= number of chunksfor directory hashes, we need two components:
- something to mix together the top-level checksum from the entry's content with the entry name string. since we really do want to catch name changes that don't change the content we will have to think harder here. maybe up to a certain name length we just store the whole name in-place along with the hash value. the point is to get a standard-size hash value we can cast into an integer
- we use modular exponentation (i.e. diffie-hellman) to commutatively hash the directory entries
that's it!
it should be possible to store the resulting hash tree in a fixed amount of space per directory entry, and you can limit the size of the transmitted hash tree by just stopping your bread-first search after some point
then you get a certificate that not only indexes into a remote object db, it's also self-certifying
@realn2s @heptapodEnthusiast this comes from the other thing i really wanted, which was to avoid having to recompute the whole hash tree upon change. so you can have a hash tree all the time with (hopefully) much less performance impact
@hipsterelectron DH and RSA are the canonical examples of vulnerable to factoring or discrete logarithm breakthroughs and surprise, that's exactly what Shor's algorithm does.
