@lindorm/rsa

RSA signature kit built on Node's crypto module and @lindorm/kryptos. Provides an RsaKit class that implements the IKeyKit contract used across the Lindorm cryptography packages.

Installation

npm install @lindorm/rsa

Quick Start

import { RsaKit } from "@lindorm/rsa";
import { KryptosKit } from "@lindorm/kryptos";

const kryptos = KryptosKit.generate.sig.rsa({ algorithm: "PS256" });
const kit = new RsaKit({ kryptos });

// Sign
const signature = kit.sign("hello world");

// Verify
kit.verify("hello world", signature); // true

// Assert (throws RsaError if invalid)
kit.assert("hello world", signature);

// Format Buffer to string
kit.format(signature); // base64 string

Constructor Options

new RsaKit({
  kryptos, // IKryptos — must be an RSA key with a signing algorithm
  dsa: "der", // DsaEncoding — "der" | "ieee-p1363" (default: "der")
  encoding: "base64", // BufferEncoding — output encoding (default: "base64")
});

The constructor validates that the key is an RSA type with a supported signing algorithm (RS256, RS384, RS512, PS256, PS384, PS512). Encryption keys (RSA-OAEP etc.) are rejected with an RsaError.

API

class RsaKit implements IKeyKit {
  sign(data: KeyData): Buffer;
  verify(data: KeyData, signature: KeyData): boolean;
  assert(data: KeyData, signature: KeyData): void; // throws RsaError
  format(data: Buffer): string;
}

KeyData is Buffer | string.

Supported Algorithms

| Algorithm | Padding | Hash | | --------- | ----------- | ------- | | RS256 | PKCS#1 v1.5 | SHA-256 | | RS384 | PKCS#1 v1.5 | SHA-384 | | RS512 | PKCS#1 v1.5 | SHA-512 | | PS256 | PSS | SHA-256 | | PS384 | PSS | SHA-384 | | PS512 | PSS | SHA-512 |

Error Handling

All errors are RsaError instances:

import { RsaError } from "@lindorm/rsa";

License

AGPL-3.0-or-later