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@kejun/cert-tools

v0.2.0

Published

Decode X.509 certificates and CSRs (Certificate Signing Requests) from PEM or DER

Readme

cert-tools

Decode X.509 certificates and CSRs (Certificate Signing Requests) from PEM format in Node.js.

Install

npm install @kejun/cert-tools

Usage

Decode X.509 Certificate

import { decodeX509 } from "@kejun/cert-tools";

const pem = `-----BEGIN CERTIFICATE-----
MIICpTCCAY2gAwIBAgIB...
-----END CERTIFICATE-----`;

const certs = await decodeX509(pem);
console.log(certs[0].subject);       // "CN=localhost"
console.log(certs[0].issuer);
console.log(certs[0].isValid);       // true/false
console.log(certs[0].thumbprintSha256);

Decode CSR

import { decodeCsr } from "@kejun/cert-tools";

const pem = `-----BEGIN CERTIFICATE REQUEST-----
MIICgDCCAWgCAQAwOzEZ...
-----END CERTIFICATE REQUEST-----`;

const info = decodeCsr(pem);
console.log(info.subject);           // { "Common Name (CN)": "example.com", ... }
console.log(info.publicKeyAlgorithm); // "RSA"
console.log(info.publicKeySize);      // "2048 bits"
console.log(info.subjectAltNames);    // ["DNS: example.com", ...]

API

decodeX509(pem: string): Promise<CertInfo[]>

Parses one or more PEM-encoded X.509 certificates. Returns an array of CertInfo objects with:

subject, issuer, serialNumber, notBefore, notAfter, isValid, signatureAlgorithm, publicKeyAlgorithm, publicKeySize, thumbprintSha1, thumbprintSha256, extensions, subjectAltNames, pem

decodeCsr(pem: string): CsrInfo

Parses a PEM-encoded CSR. Returns a CsrInfo object with:

subject, publicKeyAlgorithm, publicKeySize, signatureAlgorithm, attributes, subjectAltNames

License

MIT