@peculiar/asn1-asym-key

This package provides ASN.1 schema definitions for the asymmetric key packages format specified in RFC5958. This format is used to encapsulate private and public keys, along with additional parameters and metadata, for a variety of asymmetric key algorithms.

The schema definitions are based on @peculiar/asn1-schema library and can be used to encode and decode key packages in ASN.1 DER format.

Installation

You can install the package using npm:

npm install @peculiar/asn1-asym-key

Usage

The @peculiar/asn1-asym-key package exports several classes and constants that can be used to encode and decode key packages. Here is an example of decoding a key package for an RSA private key:

import * as assert from "node:assert";
import { OneAsymmetricKey } from "@peculiar/asn1-asym-key";
import { id_rsaEncryption, RSAPrivateKey } from "@peculiar/asn1-rsa";
import { AsnConvert } from "@peculiar/asn1-schema";

const pem = [
  "MIIEvQIBADANBgkqhkiG9w0BAQEFAASCBKcwggSjAgEAAoIBAQC+G9YX1BboIIty",
  "ZdjEnPeoJXh5J3UQak+lkO+KirllYeNQML7ent3l9KOp0tM/IfxSDmVWtyYAUoxM",
  "3TGnDoJgCCn5jUQIdQkPXTxa7xeL11W4d0fqyaAOyMOXA2QZShE61dBEz9ly+bnI",
  "N1MrcwLe0q/TPuKS1EBp8LS/lQzW/PrHTnDHwoGinBZq58B/ErgmPh27QlkhamdX",
  "G4KxDdN2ayilmvdG06dMwrGKs2Tag5HKbUSMPA3BlKvvqrJhMb3w86xPf2MnvWzV",
  "Wmi0tpE2zcCgXkX+4VtiikBW1QoFuFjiBWNJKWMXe2UKXYbdYFBPzaJiGCdiYXXJ",
  "u1N16pSxAgMBAAECggEAMoUjN+Hc1IMRi60VFerAxaZvhYK+0UXvNIh3n9GNwyto",
  "RP8vOent/hYtCAxGpxhY/VVmCM1TA/Lr5eFCOKraarrArNilo7m2VqboSyIOl9L5",
  "rLPGINbD+inQEGmOSEoumfwIBMFXf/5tKI/LQlimAqDqqLCldW+CTqTw45iweND8",
  "E+U9AddCIWS34KwMCqH20/m6crjW32b9CvaMVL0/S2FrXBeGj3QOxqoMCgMmx6tF",
  "GM3NlIIJIuICrZcPTB3c89LtY57uNrCe6o2nVZVh/1MKVbiuY5s3B5lhW86xT9ju",
  "qdCaatAD/xHDSo2w9KcVLhheUW2yLk0Hl3xt8+aZIQKBgQDu6lQcFGQoENNEJmeO",
  "mbb30lGLJRcK0ITNtc1VCW1eLXz2WJSu3CJ0L5cMct6awnaW0TjHG+/Hi/WhQo2k",
  "tl2AN3uLn6ZujXLuWv2NluUnEsNTexGR3iBo962budW9FmWWpFB7qWrOEu8gKUE9",
  "HMoOBa7vMq/ulgNuG8IcRFpepwKBgQDLtAlAfPpWYodrw8vbA5vvg05QyWQyj3zg",
  "go+SB+mKrXZFJv/k1JriDWajCMqMFLpcKbpzwxbN1umhq+l5zmJHG20OXR24bhfY",
  "viWPOK1v84Sy3f5xn/c8daymp1g+QdcwvPP9cjNAe1mNQNEYNg/SvDifhU8BAB6t",
  "p5B6VZj05wKBgBrjpLPEV8Fqo1x4Ng+GnWEm+qZ+dilxboD4hTOc7AI9fGL9dT54",
  "6CfLc2SjSQqB+Hbg9VLzgfkjd3G+29I99CgKFo2QWlr28IiDFSZqZUAQjItIvqF8",
  "Lomh1phAQh4V9zkNJUHFv4+R8ffcrMsEAnmxig7B1as0lw49cYtc5g7hAoGAYsBN",
  "t+ieh6BOXCzYN72hK9Sw87MeEvDCrig9J6MUUblT26RTa4Cx8SJj/md1ocEusx07",
  "mYEbHgCw1EJ99iHaPPSLwunbTZx5jQZpOOxWEC6yxu+duUG+Xp4Ba+02dz/97U+8",
  "zMI/HGRv/m1MsHsM4rGClbrPmQGQ3cic3uF+PEMCgYEAuUPGA2n5D4TtP64l3xxO",
  "C+TZzy1l+rd0yDbfnmGJxeOx6YdaPk0EwkhfUigUmSxcKR9Yv8tT//s9qzrqqwLk",
  "pCuOtlM+ru5rJRVV2/Nm2izNSn9IePGPmLhCUZUVZzQqUR0d3caNKtR8urR04Y15",
  "dll8U0BCsgO6JQPk9riOsdU=",
].join("");

const key = AsnConvert.parse(Buffer.from(pem, "base64"), OneAsymmetricKey);
assert.strictEqual(key.privateKeyAlgorithm.algorithm, id_rsaEncryption);

const rsaKey = AsnConvert.parse(key.privateKey, RSAPrivateKey);
console.log(rsaKey);
/*
RSAPrivateKey {
  version: 0,
  modulus: Uint8Array(257) [ 0, 190,  27, 214, ...],
  publicExponent: Uint8Array(3) [ 1, 0, 1 ],
  privateExponent: Uint8Array(256) [ 50, 133,  35,  55, ...],
  prime1: Uint8Array(129) [ 0, 238, 234,  84,  ...],
  prime2: Uint8Array(129) [ 0, 203, 180,   9,  ...],
  exponent1: Uint8Array(128) [ 26, 227, 164, 179, ...],
  exponent2: Uint8Array(128) [ 98, 192,  77, 183, ...],
  coefficient: Uint8Array(129) [ 0, 185,  67, 198, ...]
}
*/