The (few) Memes of Crypto

Question

Catchphrases and concepts that spread from person to person are known as memes, which, courtesy the Internet, can now explode across the Earth like a highly contagious virus (hence "going viral"). As with their real-life counterparts, some infectious diseases are global (pandemic), while others are endemic to specific regions.

Cryptography has seen a some of such memes and which are now part of our culture here on Crypto.SE and relateds (Meta, Sidechannel).

Just as travelers' immune systems can be assaulted by new diseases in new places, new users are increasingly likely to be miffed by an ingrained meme and left sitting scratching their heads. I therefore propose that this space be used to document the memes endemic to Crypto's culture.

Each meme should be listed separately and I hope that we as a community will be able to provide greater context to each one.

Each meme should be listed separately and I hope that we as a community will be able to provide greater context to each one.

Please actually explain each meme in a way understandable to those not already in the know of it and the related concepts.

This question was mainly stolen from PPCG, which itself stole it mainly from Meta.

Answer 1

Meme: Meat-In-The-Middle Attack

Originator: Mikeazo

Background: In a question about a dubious cryptosystem Mike trusted the auto-correction of his phone a bit too much resulting in the misspelling of the meet-in-the-middle attack, which breaks common double encryption, as meat-in-the-middle attack. This was conceived funny by many among the Crypto.SE community and became a bit of a gag in the chat.

Usage Examples:

• The first appearance in the chat with the answer of E-Sushi grilling.
• The second appearance with the threat of grilling again.

Answer 2

Meme: The NSA (No Such Algorithm) assumption

Originator: Mikeazo

Background: On The Side Channel we were discussing exciting new cryptographic assumptions that could help in a submission to the Snake Oil Crypto Competition. Given recent events with crypto backdoors and leaks coming out of the National Security Agency, we felt obliged to build an assumption off of agency's acronym. Thus was born the No Such Algorithm assumption.

Example Usage:

For example, in chat we proposed the cipher-cipher-chaining-padded mode for block ciphers, which turns out to be perfectly secure under the NSA assumption. In other words, the mode provides perfect secrecy assuming there is no such algorithm that proves otherwise.

Answer 3

Meme: Why does the porridge bird lay his egg in the air?

Originator: Squeamish Ossifrage

Background

In the question collection for the (first) 2018 moderator election, Squeamish Ossifrage posed the question "Why does the porridge bird lay his egg in the air?". Needless to say, some confusion ensued - but this confusion is actually appropriate given the origin of the quote.

In the comedy radio show The Firesign Theater, there is an episode called "I think we're all Bozos on this bus". It is about a visit to the "Future Fair". Present at this fair are robots and the like.

At one point, a character intentionally supplies a maliciously crafted phrase to a robot to cause it to malfunction. This is an example of an attack that was written in 1971!

Example usage: This question tests a moderator candidates ability to respond to nonsense and/or intentionally malformed information. Hopefully they don't go haywire like the robot in the show did!

Answer 4

Meme: Yes We Don't.

Originator: Squeamish Ossifrage, and yyyyyyy.

Background: In this question asking how can we be certain that current cryptosystems won't get broken all of a sudden, yyyyyyy answered in two words: "We don't" - a painful fact which everyone must acknowledge, and something must be accepted without thinking - elegantly summarized in just 2 words.

Then later, a meta question asking literally: "Is a two word answer to a complex question really acceptable", Squeamish Ossifrage answered in tribute to yyyyyyy "Yes" - elegant in every way, and controversial as it received many up votes not because people agree with it (although some might), but because of its satirical value.

Answer 5

Meme: Demonstrating Collision with Photos.

Originator: Thomas Pornin.

Background: Modern cryptographic hash functions are designed securely such that it's practically impossible to find two different messages that hashes to the same value. Of course, the design of secure hash functions didn't occur overnight, and some past hash algorithms such as MD5 had been broken. In an attempt to explain the improbableness of SHA256 collision, Thomas Pornin brought up statistics showing, it's more likely to get assaulted by escaped zoo animal, than having a SHA256 hash collision and illustrated his answer with an image macro.

One month later, some unknown user by the name of Adban asked Are there two known strings which have the same MD5 hash value?, where he received an illustrated answer five years later from Silverfox, who had shown two pictures supposedly having same MD5 digest (it got altered by imgur somehow). Two pictures, one showing a shipwreck, the other an fighter jet crash, invited a pundit commenting:

... Btw only looking at the pictures clearly shows there is a collision somewhere… ;-)

Also: Not related, but Google together with researchers in Netherlands demonstrated world's first SHA1 collision with two PDF files.

Answer 6

Meme: Sum of two words with carries suppressed.

Originator: whole_lotta_coins

Background: In this recent question, an unsuspecting user was badly confused with the way Salsa20 specification describe the XOR operation. XOR is a well-known operation in cryptography, in binary-represented characteristic-2 finite fields, XOR is exactly the way to implement field element addition. However, the way the author describe it caused unnecessary confusion as evident by the way OP put it:

The author defines the operation as the sum of two words with carries suppressed, but what does "carries suppressed" mean?

Finally in the answer, our pundit pointed out bluntly:

The sum of two words with carries suppressed is just a convoluted way to say XOR.