Linked Questions

19 votes
2 answers

How is encryption broken today?

There are often articles in the news that state that a certain country or hacker has been able to decrypt/hack highly protected systems: Some examples are the Lockheed Martin RQ-170 Sentinel that was ...
Quasar's user avatar
  • 301
14 votes
2 answers

Interesting implementation practices in popular crypto library

So reading through the salsa20 implementation for the crypto library for go-lang, I noticed something interesting. Specifically this portion. It looks like something I would expect from someone ...
abrahimladha's user avatar
12 votes
2 answers

Are there any signature schemes for underpowered devices (8-bit microcontroller)?

I am currently researching into a small scale home automation system, aiming for cost. The system architecture is basically one master and several slaves which are connected in parallel. Recently i'...
Bruno Morais's user avatar
7 votes
1 answer

What is a smart card?

In many cryptographic protocols, some information is transmitted within smart cards. So, what is a smart card? Is it a physical card? What are they used for in cryptographic protocols?
user4665's user avatar
  • 245
4 votes
2 answers

How insecure is AES-128-CTR to encrypt any kind of data using the Ethereum keystore file format?

I am using the Ethereum keystore file format to encrypt any other data such a plain text or JSON. Here is an example of pseudocode of the implementation: ...
Enzo's user avatar
  • 151
6 votes
1 answer

SHA256 HMAC brute force with chosen plaintext attacks

This is a follow up to Is It Possible To Reconstruct a Cryptographic Hash's Key I am using a SHA-256 HMAC function on a single-word input: sha256hmac(privatekey,word) = output. The private key length ...
user1373208's user avatar
8 votes
2 answers

Timing attack on modular exponentiation

It is known that computing $a^x \bmod N$ takes $O(|x| + \mathrm{pop}(x))$ multiplications modulo $N$, where $|x|$ is the number of bits of $x$ and $\mathrm{pop}(x)$ is the number of $1$ bits (Hamming ...
Smit Johnth's user avatar
  • 1,691
3 votes
2 answers

How are these AES MixColumn multiplication tables calculated?

I'm using the mul2, mul3, mul9, mul11, mul13 and mul14 tables for the MixColumn and InvMixColumn steps in AES-128. However, I got these off some Github repository, and now I'm looking for an actual ...
Satoutan's user avatar
3 votes
1 answer

Attacks on Aes (128-192-256) [duplicate]

I have a direct question Is there any practical attacks on the AES cryptosystem (128-192-256 keys)
user58232's user avatar
9 votes
1 answer

Do people not care about side channel resistance?

Recently, I have been browsing a lot through libraries that implementing Shamir secret sharing. I see a lot of code that implements this cryptographic algorithm without any side channel (timing/branch/...
dusk's user avatar
  • 1,175
4 votes
1 answer

Have crypto side-channel attacks happened in the wild?

I'm aware of attacks extracting information via timing and volume. But none that care or attack the actual cryptographic algorithm implementation or end up extracting the key. Seeking examples if any ...
Meir Maor's user avatar
  • 11.8k