Tag: symmetric cryptography

Cryptography

Database Cryptography Fur the Rest of Us

Post author By Soatok
Post date March 1, 2023
7 Comments on Database Cryptography Fur the Rest of Us

An introduction to database cryptography.

Tags applied cryptography, block cipher modes, cryptography, database cryptography, databases, encrypted search, HMAC, MongoCrypt, MongoDB, Queryable Encryption, real-world cryptography, security, Security Guidance, SQL, SSE, symmetric cryptography, symmetric searchable encryption

Cryptography Software Security

Threema: Three Strikes, You’re Out

Post author By Soatok
Post date November 5, 2021
11 Comments on Threema: Three Strikes, You’re Out

Threema boldly claims to be more secure than Signal. Does this hold up to scrutiny?

Tags cryptography, Online Privacy, privacy, private messaging, symmetric cryptography, Threema, Vulnerability, Zero-Day

Bullshit Cryptography

Crackpot Cryptography and Security Theater

Post author By Soatok
Post date February 9, 2021
5 Comments on Crackpot Cryptography and Security Theater

Tales from the Crypt[ography].

Tags asymmetric cryptography, crackpots, Crown Sterling, cryptography, kooks, post-quantum cryptography, quantum computers, scam artists, scammers, scams, symmetric cryptography, Terra Quantum, Time AI

Cryptography Software Security

Please Stop Encrypting with RSA Directly

Post author By Soatok
Post date January 20, 2021
8 Comments on Please Stop Encrypting with RSA Directly

RSA is for encrypting symmetric keys, not entire messages. Pass it on.

Tags asymmetric cryptography, cryptography, RSA, Security Guidance, symmetric cryptography

Cryptography

Block Cipher Structures: Ranked

Post author By Soatok
Post date January 11, 2021
No Comments on Block Cipher Structures: Ranked

An opinionated curation of different classes of block ciphers, ranked by an opinionated furry.

Tags block ciphers, cryptography, symmetric cryptography, symmetric encryption

Cryptography

Cryptographic Wear-Out for Symmetric Encryption

Post author By Soatok
Post date December 24, 2020
20 Comments on Cryptographic Wear-Out for Symmetric Encryption

As we look upon the sunset of a remarkably tiresome year, I thought it would be appropriate to talk about cryptographic wear-out. What is cryptographic wear-out? It’s the threshold when you’ve used the same key to encrypt so much data that you should probably switch to a new key before you encrypt any more. Otherwise, […]

Tags AES, AES-CBC, AES-GCM, birthday attack, birthday bound, cryptography, safety margin, Security Guidance, symmetric cryptography, symmetric encryption, wear-out

Cryptography

Designing New Cryptography for Non-Standard Threat Models

Post author By Soatok
Post date September 9, 2020
7 Comments on Designing New Cryptography for Non-Standard Threat Models

Since the IETF’s CFRG decided to recommend OPAQUE as a next-generation Password Authenticated Key Exchange, there has been a lot of buzz in the cryptography community about committing authenticated encryption (known to the more academically inclined as Random Key Robustness), because OPAQUE requires an RKR-secure AE scheme. Random Key Robustness is a property that some […]

Tags BLAKE3, ChaCha20, cryptography, random-key robustness, Security Guidance, symmetric cryptography

Cryptography Software Security

Soatok’s Guide to Side-Channel Attacks

Post author By Soatok
Post date August 27, 2020
20 Comments on Soatok’s Guide to Side-Channel Attacks

If you’re ever tasked with implementing a cryptography feature–whether a high-level protocol or a low-level primitive–you will have to take special care to ensure you’re not leaking secret information through side-channels. The descriptions of algorithms you learn in a classroom or textbook are not sufficient for real-world use. (Yes, that means your toy RSA implementation […]

Tags asymmetric cryptography, constant-time, cryptography, ECDH, ECDSA, elliptic curve cryptography, RSA, Security Guidance, side-channels, symmetric cryptography

Cryptography

Comparison of Symmetric Encryption Methods

Post author By Soatok
Post date July 12, 2020
10 Comments on Comparison of Symmetric Encryption Methods

There seems to be a lot of interest among software developers in the various cryptographic building blocks (block ciphers, hash functions, etc.), and more specifically how they stack up against each other. Today, we’re going to look at how some symmetric encryption methods stack up against each other. If you’re just looking for a short […]

Tags AEAD, AES, AES-GCM, AES-GCM-SIV, ChaCha20-Poly1305, ciphers, comparison, cryptography, encryption, NMR AEAD, ranking, Security Guidance, stream ciphers, symmetric cryptography, symmetric encryption, XChaCha20-Poly1305

Cryptography

Why AES-GCM Sucks

If you’re reading this wondering if you should stop using AES-GCM in some standard protocol (TLS 1.3), the short answer is “No, you’re fine”. I specialize in secure implementations of cryptography, and my years of experience in this field have led me to dislike AES-GCM. This post is about why I dislike AES-GCM’s design, not […]

Tags AES, AES-GCM, cryptography, Galois/Counter Mode, opinion, Security Guidance, symmetric cryptography