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Replace non-browser-friendly createPrivateKey call with custom function to convert pkcs1 to pkcs8

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This commit is contained in:
GCHQDeveloper581 2026-05-29 20:33:33 +00:00
parent cc1d4582bd
commit 3c03e64e6f
No known key found for this signature in database
GPG Key ID: 6222E059A3DF595C
2 changed files with 51 additions and 3 deletions
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49
src/core/lib/RSA.mjs
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@ -7,6 +7,7 @@
*/
import forge from "node-forge";
import * as asn1js from "asn1js";
export const MD_ALGORITHMS = {
"SHA-1": forge.md.sha1,
@ -15,3 +16,51 @@ export const MD_ALGORITHMS = {
"SHA-384": forge.md.sha384,
"SHA-512": forge.md.sha512,
};
const rsaEncryptionOID = "1.2.840.113549.1.1.1";
/**
* Convert PKCS#1 RSA private key (PEM) to PKCS#8 PEM
* @param {string} originalPem
* @returns {string}
*/
export function pkcs1ToPkcs8(originalPem) {
// remove PEM headers
const b64 = originalPem
.replace(/-----BEGIN RSA PRIVATE KEY-----/g, "")
.replace(/-----END RSA PRIVATE KEY-----/g, "")
.replace(/\s+/g, "");
const pkcs1Der = Uint8Array.from(atob(b64), c => c.charCodeAt(0)).buffer;
// PKCS#8 structure:
// PrivateKeyInfo ::= SEQUENCE {
// version INTEGER,
// privateKeyAlgorithm AlgorithmIdentifier,
// privateKey OCTET STRING
// }
const pkcs8Schema = new asn1js.Sequence({
value: [
new asn1js.Integer({ value: 0 }),
new asn1js.Sequence({
value: [
// rsaEncryption OID
new asn1js.ObjectIdentifier({ value: rsaEncryptionOID }),
new asn1js.Null()
]
}),
new asn1js.OctetString({ valueHex: pkcs1Der })
]
});
const pkcs8Der = pkcs8Schema.toBER(false);
const pkcs8B64 = btoa(
String.fromCharCode(...new Uint8Array(pkcs8Der))
);
const lines = pkcs8B64.match(/.{1,64}/g).join("\n");
return `-----BEGIN PRIVATE KEY-----\n${lines}\n-----END PRIVATE KEY-----`;
}

5
src/core/operations/JWTSign.mjs
View File

@ -5,10 +5,9 @@
*/
import Operation from "../Operation.mjs";
import { SignJWT, importPKCS8 } from "jose";
import { createPrivateKey } from "crypto";
import OperationError from "../errors/OperationError.mjs";
import {JWT_ALGORITHMS} from "../lib/JWT.mjs";
import {pkcs1ToPkcs8} from "../lib/RSA.mjs";
/**
* JWT Sign operation
@ -57,7 +56,7 @@ class JWTSign extends Operation {
let secret;
try {
if (key.startsWith("-----BEGIN RSA PRIVATE KEY-----")) {
secret = await createPrivateKey(key);
secret = await importPKCS8(pkcs1ToPkcs8(key), algorithm);
} else if (key.startsWith("-----BEGIN PRIVATE KEY-----")) {
secret = await importPKCS8(key, algorithm);
} else {