Add EE license support for air-gapped / offline environments

backend/src/lib/crypto/index.ts

@@ -17,4 +17,5 @@ export {
   decryptSecrets,
   decryptSecretVersions
 } from "./secret-encryption";
+export { verifyOfflineLicense } from "./signing";
 export { generateSrpServerKey, srpCheckClientProof } from "./srp";

backend/src/lib/crypto/license_public_key.pem

@@ -0,0 +1,8 @@
+-----BEGIN RSA PUBLIC KEY-----
+MIIBCgKCAQEApchBY3BXTu4zWGBguB7nM/pjpVLY3V7VGZOAxmR5ueQTJOwiGM13
+5HN3EM9fDlQnZu9VSc0OFqRM/bUeUaI1oLPE6WzTHjdHyKjDI/S+TLx3VGEsvhM1
+uukZpYX+3KX2w4wzRHBaBWyglFy0CVNth9UJhhpD+KKfv7dzcRmsbyoUWi9wGfJu
+wLYCwaCwZRXIt1sLGmMncPz14vfwdnm2a5Tj1Jbt0GTyBl+1/ZqLbO6SsslLg2G+
+o7FfGS9z8OUTkvDdu16qxL+p2wCEFZMnOz5BB4oakuT2gS9iOO2l5AOPcT4WzPzy
+PYbX3d7cN9BkOY9I5z0cX4wzqHjQTvGNLQIDAQAB
+-----END RSA PUBLIC KEY-----

backend/src/lib/crypto/signing.ts

@@ -0,0 +1,22 @@
+import crypto, { KeyObject } from "crypto";
+import fs from "fs/promises";
+import path from "path";
+
+export const verifySignature = (data: string, signature: Buffer, publicKey: KeyObject) => {
+  const verify = crypto.createVerify("SHA256");
+  verify.update(data);
+  verify.end();
+  return verify.verify(publicKey, signature);
+};
+
+export const verifyOfflineLicense = async (licenseContents: string, signature: string) => {
+  const publicKeyPem = await fs.readFile(path.join(__dirname, "license_public_key.pem"), "utf8");
+
+  const publicKey = crypto.createPublicKey({
+    key: publicKeyPem,
+    format: "pem",
+    type: "pkcs1"
+  });
+
+  return verifySignature(licenseContents, Buffer.from(signature, "base64"), publicKey);
+};