libsumatracrypt-rs

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libsumatracrypt-rs is an open-source cryptography library written in pure-rust that is strictly-and-inherently secure-by-design, has ease of access, has strong documentation, and offers extensions of advanced cryptography (Zero-Knowledge Proofs, Homomorphic Encryption, Post-Quantum Cryptography) while maintaining a simple-to-use interface. It uses the Sumatracrypt-Standardized-API-Model to offer an easy-to-use API interface that is hard to blunder by design. It has loads of documentation detailing out certain design choices, how it works under-the-hood, among other things.

It currently has the following cryptographic protocols implemented:

Public-Key Encryption Schemes

• Elliptic Curve Integrated Encryption System (ECIES) using CURVE25519
• RSA4096-OAEP

Digital Signature Schemes

• ED25519
• Schnorr over Ristretto Compressed Ed25519 points
• ED448 (not implemented yet)

Key Exchanges

• X448 (on Curve448)

Hash Functions (Digests)

• SHA1
• SHA2 (SHA2-224,SHA2-256,SHA2-384,SHA2-512)
• BLAKE2B (Variable Length, Supports Keyed-Hash)
• BLAKE3
• SHA3 (SHA3-224, SHA3-256, SHA3-384, SHA3-512)
• SHAKE256 (512-bits)

Cryptographically Secure Random Number Generator (CSPRNG)

• a crossplatform getrandom() for getting operating system's cryptographically secure pseudorandom number generator (CSPRNG)

Post-Quantum

Signatures

• FALCON1024

• Dilithium3

Key-Encapsulation

• Kyber1024 (KyberSlash Vulnerability; May switch to safe_pq_kyber)

General

libsumatracrypt-rs is:

• Easy-to-use

• Pure-rust (so memory-safe)

• Lightweight

• Strictly secure by design with a hard focus made on security (including side-channel attacks and advanced adversaries)

• Minimalistic, with minimal dependecies and optional dependecies

• has standardized API known as Sumatracrypt-Standardized-API-Model

• has a substancial amount of documentation, community-talk, and deep-dives into the code

• has extensions that use Advanced Cryptography (like Zero-Knowledge Proofs, Homomorphic Encryption, Post-Quantum Cryptography, Verifiable Random Functions, Verifiable Delay Functions) with Standardized API known as sumatracryptadvanced-standardized-api

Library Purpose

For General User

The purpose of libsumatracrypt-rs is to make a lightweight, pure-rust, cryptography library available to more people with security at its core (defending against even the most advanced attacks, like side-channel attacks) while maintaing ease-of-access and easy-to-use API, even against advanced attackers.

It also wants to offer easy usage of more advanced cryptographic algorithms like Zero-Knowledge Proofs, Homomorphic Encryption, and Post-Quantum Cryptography to the general public with simple front-facing API.

For Developers

The idea of development for future developers/contributors for libsumatracrypt-rs is to remain:

• Easy-To-Use with a simple interface and Standardized API using Sumatra-Standardized-API-Model.
• Lightweight with minimal dependecies (and for these dependecies to be later audited and/or later forked)
• Hard Focus on Strict Security (including measures against side-channel attacks, timing-attacks, and advanced adversaries)
• Make Dependecies Optional by default and seperate into different crates
• Make it absurdly hard for the general user to botch (misconfigure, having issues with secrets, other user configuration attacks)
• Have substancial documentation and in-depth discussions
• Have examples in every crate

For Developers (Security)

It also is meant to combat side-channel attacks and remain constant-time. Other security measures are also desirable.

General Overview

Encryption

ECIES (Curve25519) (Primary)

Elliptic Curve Integrated Encryption Scheme (ECIES) on curve25519-dalek is chosen as the primary choice for encryption.

RSA4096-OAEP

RSA4096-OAEP uses the pure-rust rsa crate. It only gener

PKCS#8 Note: uses LF (\n) by default for privacy so no-one can figure out where you generated the key from.

Hash Functions

• SHA2 (SHA224,SHA256,SHA384,SHA512)
• SHA3 (SHA3-224,SHA3-256,SHA3-384,SHA3-512)
• SHAKE256
• BLAKE2B (Variable Digest)
• BLAKE3

Digital Signatures

• Schnorr
• ED25519
• RSA4096 (to-do)

List of Availble Protocols Currently Implemented

Encryption

• ECIES-Curve25519
• RSA4096-OAEP

ECIES-CURVE25519

• [Security] Implements Zeroize/ZeroizeOnDrop for all structs

RSA4096

• [Encoding] Implements PEM (PKCS#8)

Digital Signatures

• Schnorr Signature over CURVE25519
• ED25519

ED25519

ED25519 is a cryptographic digital signature algorithm that uses Curve25519.

PublicKey: 32-bytes (256 bits)

SecretKey: 32-bytes (256 bits)

Signature: 64 bytes (512 bits)

Details

By default, all keys are encoded as a String in upper-hexadecimal encoding and will result in 2*x the size in characters. This means the public key is 64 characters long, the secret key is 64 characters long, and the signature is 128 characters long.

Security

• [Security] [Secret-Key-Generation] Secret Key comes from Operating-System CSPRNG of size 32-bytes as an array.
• [Security] [Zeroize] Implements Zeroize/ZeroizeOnDrop for all structs

Developer Notes

The structs (ED25519PublicKey, ED25519SecretKey, ED25519Signature) are stored as String in Upper-Hexadecimal Encoding.

• [Security] Secret Key is generated from 32-bytes (256) of CSPRNG from operating system as an [u8;32] | array

TODO:

Encryption

SumatraEncryptECIES | Elliptic Curve Integrated Encryption Scheme (ECIES) over Twisted Edwards Curve25519 using AES-GCM and HKDF-SHA256 in pure-rust.

• Boasts strong security guarentees, fast speeds, and small key sizes.
• Depends On: Uses the ecies-ed25519 crate with the pure feature flag.

SumatraRSA4096 | RSA4096 using Optimal Asymmetric Encryption Padding (OAEP) in pure-rust.

• Boasts strong security with well-reviewed, classical security arguments against the well-tested RSA algorithm, offering only one key size (the highest key size with the most security).
• Generation takes around 3-5 minutes for a new RSA4096 key. Good for long-term keys with classical security assumptions.
• Depends On: Uses the audited rsa crate

Digital Signatures

SumatraEd25519 | Constant-Time ED25519 Sinature Scheme in pure-rust.

Ed25519 (view Website) is a cryptographic digital signature scheme that offers strong security with protection against various side-channel attacks and branching prediction. It is blazingly fast, offering

SumatraEd25519 offers strong security through its extensive use of the ed25519-dalek crate for ED25519 signatures. These signatures offer strong security by remaining constant-time, implementing zeroize, and being less vulnerable to side-channel attacks. It uses Curve25519.

Constant-Time

• Schnorr Signatures

Hash Functions

• SHA2 (SHA224,SHA256,SHA384,SHA512)