Cryptography

DeroAuth performs signature verification using DERO's native cryptographic primitives — entirely in TypeScript.

Schnorr Signatures on BN256

DERO uses Schnorr signatures on the BN256 (Barreto-Naehrig 254-bit) elliptic curve. This is fundamentally different from Bitcoin/Ethereum which use ECDSA on secp256k1.

Signature Scheme

A Schnorr signature consists of (s, e) where:

• e = H(R || P || M) — hash of the nonce point, public key, and message
• s = r - e * x — the scalar response (where x is the private key, r is the nonce)

Verification checks: s*G + e*P == R

Hash Function

DERO uses Keccak-256 (not SHA-256) for signature hashing. The hash output is reduced modulo the curve order to produce a scalar.

import { reducedHash } from "dero-auth/crypto";
 
// Keccak-256 of the input, reduced mod curve order
const scalar = reducedHash(messageBytes);

DERO's Custom Generator Point

The custom generator is defined in dero-auth/crypto and was reverse-engineered from the DERO Go source code. This is the single most important implementation detail for anyone attempting DERO signature verification.

Address Format

DERO addresses use Bech32 encoding with a 33-byte compressed G1 public key:

dero1qy[...rest of bech32...]

The dero-auth/crypto module provides encoding and decoding:

import { decodeAddress, encodeAddress, isValidAddress } from "dero-auth/crypto";
 
// Decode address to get the public key bytes
const publicKeyBytes = decodeAddress("dero1qy...");
// Returns: Uint8Array (33 bytes, compressed G1 point)
 
// Encode a public key back to an address
const address = encodeAddress(publicKeyBytes);
 
// Validate format
const isValid = isValidAddress("dero1qy...");

PEM Signature Format

DERO wallets produce signatures in PEM format — a base64-encoded block wrapped in header/footer lines:

-----BEGIN DERO SIGNED MESSAGE-----
[base64 encoded signature data]
-----END DERO SIGNED MESSAGE-----

import { parsePEM } from "dero-auth/crypto";
 
const { signature, publicKey } = parsePEM(pemString);

Verification Pipeline

The full verification process:

import { verifySignature } from "dero-auth/crypto";
 
const result = verifySignature({
  message: challengeMessage,
  signature: pemSignature,
  address: "dero1qy...",
});
 
if (result.valid) {
  // Signature is mathematically valid
  // result.address contains the verified DERO address
}

Under the hood:

1. Parse PEM to extract raw signature bytes
2. Decode the DERO address to a compressed G1 public key
3. Decompress the public key to a full curve point
4. Hash the message with Keccak-256, reduce mod curve order
5. Verify the Schnorr equation: s*G + e*P == R

Dependencies

All cryptographic operations use audited libraries:

• @noble/curves — BN256 curve operations (audited by Cure53)
• @noble/hashes — Keccak-256 hashing (audited by Cure53)

No custom cryptographic implementations.