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13

I'd say that the whole argument hinges around a "secret attack" that possibly the NSA may know of, enabling them to break some instances of elliptic curves that the rest of the World considers as safe, because the secret attack is, well, secret. This yields to the only possible answer to your question: since secret attacks are secret, they are not known to ...


7

The answer is yes, non-US ciphers exist and are in fact very popular. Actually, some who are looking for alternatives, opt for non-NSA/NIST ciphers, for instance Salsa/ChaCha from DJB (who is US citizen). A lot of ciphers have been developed in EU and Japan. China definitely has developed ciphers for its own use, just like many other countries. But long ...


7

With any $n$ bit hash it is possible to: Find preimages with work $2^n$ on classical computers and $2^{n/2}$ using quantum computers Find collisions with work $2^{n/2}$ on classical computers and $2^{n/3}$ using quantum computers I want to emphasize that these are generic attacks that always work, no matter which concrete hashfunction is used. Grover's ...


7

As an Iranian Cryptology student in one of the most well-known Iranian Universities called Sharif University of Technology, I want to add this to the answers. There doesn't seem to be any National Standard Cipher here in Iran. But It doesn't mean that there shouldn't be any classified cipher being used by the military or the revolutionary guards. As I am ...


7

I would characterize the service as similar to a trusted time-stamping service. Except they do not do the time-stamping, but just provide the "key". This allows a user to decide what do to with it, such as using it as a private key to sign something, or an HMAC key, proving the signature is "not older" than the timestamp. If the signature is published to a ...


6

This has been basically asked already: Should we trust the NIST recommended ECC parameters? History Once it was found that NSA allegedly had inserted backdoor to a cryptographic standard, people started thinking what standard it was. The most common guess is that the Dual EC DRBG is the backdoored standard. However, some amount of (possibly justified) ...


6

Plenty of ciphers come out of the USA from government research or selection competitions. AES and DES are examples. Indeed, the US is known from some crypto-related competitions that were/are ope to anyone and they surely will do ample of government research related to cyptology, but you need to be sure that you differ between “they selected it” and ...


5

No they did not, the internals and security levels have not been changed from the draft Keccak submission, only the padding rule has changed. The padding change is the only difference, this allows future tree hashing modes as well as the current SHAKE outputs to generate different digests given the same security parameters and message inputs. Up to 4 ...


4

You are using the wrong value as the modulus; you ought to be using the value $r$ (which is also listed in the document). $p$ is the characteristic of the field that the elliptic curve you're using is defined on. In this case, we're not interested in that; instead what we're interested in is the order of the curve, that is, that value $r$ such that $rP = ...


3

The routine you link to is already performing that check (lines 15-17): it returns $(0,0,0)$ when $S$ and $T$ are equal, and the caller is expected to handle this by calling the doubling routine. The equality verification is performed by checking whether $$X_1Z_2^2 - X_2Z_1^2 = 0$$ $$Y_1Z_2^3 - Y_2Z_1^3 = 0$$ It is easy to see that, since $x = X/Z^2$ ...


3

Yes. The Serpent Cipher was developed outside of America, and isn't maintained by an American group. It came in 2nd place during the AES competition. It has a higher safety factor than AES (Rijndael), but isn't as fast. And there are stream ciphers being developed and validated by eSTREAM in Belgium. The Salsa20 stream cipher, by American cryptographer ...


3

PRNGs are a difficult and hot topic. Some tests can be found here: What tests can I do to ensure my PRNG is working correctly? But they do not tell you (or others) if your PRNG is really secure. A PRNG must be build in a way, that a third party is not able to "calculate" former or upcoming PRNG output based on some random data from the PRNG.


3

I wonder why anyone would choose to rely on a source of true random numbers fraught with questions that will ultimately have no provable - or perhaps even satisfactory - answer. There are at least a couple of companies that sell generators that provide high quality true random numbers. Having a generator on-site and available real-time allows the necessary ...


2

Background When defining protocol compliant with NIST SP 800-108, you just need to pick suitable options, which work well with your protocol. If there is a need to be compatible with a specific pre-existing protocol, you may want to take a look at NIST SP 800-135Rev1, which defines application specific key derivation functions. It is notable to recognize ...


1

The sect curves are curves over a binary field. From SEC 2: Recommended Elliptic Curve Domain Parameters (chapter 3): The example elliptic curve domain parameters over $\mathbb{F}_{2^m}$ have been given nicknames to enable them to be easily identified. The nicknames were chosen as follows. Each name begins with sec to denote ‘Standards for Efficient ...


1

First up: Don't believe the hype! Especially if things can easily be proven wrong. What I mean is that your NIST have just launched a new service… is incorrect, as the NIST Randomness Beacon project is known to me (and others) since 2011. Furthermore, this project was awarded a multi-year grant from NIST's Innovations in Measurement Science (IMS) Program in ...



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