Function main

kms/decryptAsymmetric.js:17–89

(
  projectId = 'my-project',
  locationId = 'us-east1',
  keyRingId = 'my-key-ring',
  keyId = 'my-key',
  versionId = '123',
  ciphertext = Buffer.from('...')
)

'use strict';

async function main(
  projectId = 'my-project',
  locationId = 'us-east1',
  keyRingId = 'my-key-ring',
  keyId = 'my-key',
  versionId = '123',
  ciphertext = Buffer.from('...')
) {
  // [START kms_decrypt_asymmetric]
  //
  // TODO(developer): Uncomment these variables before running the sample.
  //
  // const projectId = 'my-project';
  // const locationId = 'us-east1';
  // const keyRingId = 'my-key-ring';
  // const keyId = 'my-key';
  // const versionId = '123';
  // const ciphertext = Buffer.from('...');

  // Imports the Cloud KMS library
  const {KeyManagementServiceClient} = require('@google-cloud/kms');

  // Instantiates a client
  const client = new KeyManagementServiceClient();

  // Build the key version name
  const versionName = client.cryptoKeyVersionPath(
    projectId,
    locationId,
    keyRingId,
    keyId,
    versionId
  );

  // Optional, but recommended: compute plaintext's CRC32C.
  const crc32c = require('fast-crc32c');
  const ciphertextCrc32c = crc32c.calculate(ciphertext);

  async function decryptAsymmetric() {
    const [decryptResponse] = await client.asymmetricDecrypt({
      name: versionName,
      ciphertext: ciphertext,
      ciphertextCrc32c: {
        value: ciphertextCrc32c,
      },
    });

    // Optional, but recommended: perform integrity verification on decryptResponse.
    // For more details on ensuring E2E in-transit integrity to and from Cloud KMS visit:
    // https://cloud.google.com/kms/docs/data-integrity-guidelines
    if (!decryptResponse.verifiedCiphertextCrc32c) {
      throw new Error('AsymmetricDecrypt: request corrupted in-transit');
    }
    if (
      crc32c.calculate(decryptResponse.plaintext) !==
      Number(decryptResponse.plaintextCrc32c.value)
    ) {
      throw new Error('AsymmetricDecrypt: response corrupted in-transit');