fix!: IdTokenVerifier now throws IOException if any issue obtaining public keys. Adding retries to public key fetch to cover transient network issues. (#934)

 * fix!: IdtokenVerifier now throws IOException if any issue obtaining public keys. Adding retries to public key fetch to cover transient network issues. * fix: docs nit fixes

Author: Timur Sadykov

google-oauth-client/src/main/java/com/google/api/client/auth/openidconnect/IdTokenVerifier.java

@@ -15,6 +15,8 @@
 package com.google.api.client.auth.openidconnect;
 
 import com.google.api.client.http.GenericUrl;
+import com.google.api.client.http.HttpBackOffUnsuccessfulResponseHandler;
+import com.google.api.client.http.HttpBackOffUnsuccessfulResponseHandler.BackOffRequired;
 import com.google.api.client.http.HttpRequest;
 import com.google.api.client.http.HttpResponse;
 import com.google.api.client.http.HttpTransport;
@@ -25,6 +27,7 @@
 import com.google.api.client.util.Base64;
 import com.google.api.client.util.Beta;
 import com.google.api.client.util.Clock;
+import com.google.api.client.util.ExponentialBackOff;
 import com.google.api.client.util.Key;
 import com.google.api.client.util.Preconditions;
 import com.google.common.annotations.VisibleForTesting;
@@ -231,8 +234,10 @@ public final Collection<String> getAudience() {
  *
  * @param idToken ID token
  * @return {@code true} if verified successfully or {@code false} if failed
+ * @throws IOException if verification fails to run. For example, if it fails to get public keys
+ * for signature validation.
  */
- public boolean verify(IdToken idToken) {
+ public boolean verify(IdToken idToken) throws IOException {
  boolean payloadValid = verifyPayload(idToken);
 
  if (!payloadValid) {
@@ -242,11 +247,7 @@ public boolean verify(IdToken idToken) {
  try {
  return verifySignature(idToken);
  } catch (VerificationException ex) {
- LOGGER.log(
- Level.SEVERE,
- "id token signature verification failed. "
- + "Please see docs for IdTokenVerifier for default settings and configuration options",
- ex);
+ LOGGER.log(Level.INFO, "Id token signature verification failed. ", ex);
  return false;
  }
  }
@@ -281,7 +282,7 @@ protected boolean verifyPayload(IdToken idToken) {
  }
 
  @VisibleForTesting
- boolean verifySignature(IdToken idToken) throws VerificationException {
+ boolean verifySignature(IdToken idToken) throws IOException, VerificationException {
  if (Boolean.parseBoolean(environment.getVariable(SKIP_SIGNATURE_ENV_VAR))) {
  return true;
  }
@@ -297,12 +298,12 @@ boolean verifySignature(IdToken idToken) throws VerificationException {
  String certificateLocation = getCertificateLocation(idToken.getHeader());
  publicKeyToUse = publicKeyCache.get(certificateLocation).get(idToken.getHeader().getKeyId());
  } catch (ExecutionException | UncheckedExecutionException e) {
- throw new VerificationException(
+ throw new IOException(
  "Error fetching public key from certificate location " + certificatesLocation, e);
  }
 
  if (publicKeyToUse == null) {
- throw new VerificationException(
+ throw new IOException(
  "Could not find public key for provided keyId: " + idToken.getHeader().getKeyId());
  }
 
@@ -508,6 +509,10 @@ public Builder setHttpTransportFactory(HttpTransportFactory httpTransportFactory
 
  /** Custom CacheLoader for mapping certificate urls to the contained public keys. */
  static class PublicKeyLoader extends CacheLoader<String, Map<String, PublicKey>> {
+ private static final int DEFAULT_NUMBER_OF_RETRIES = 2;
+ private static final int INITIAL_RETRY_INTERVAL_MILLIS = 1000;
+ private static final double RETRY_RANDOMIZATION_FACTOR = 0.1;
+ private static final double RETRY_MULTIPLIER = 2;
  private final HttpTransportFactory httpTransportFactory;
 
  /**
@@ -553,6 +558,19 @@ public Map<String, PublicKey> load(String certificateUrl) throws Exception {
  .createRequestFactory()
  .buildGetRequest(new GenericUrl(certificateUrl))
  .setParser(GsonFactory.getDefaultInstance().createJsonObjectParser());
+ request.setNumberOfRetries(DEFAULT_NUMBER_OF_RETRIES);
+
+ ExponentialBackOff backoff =
+ new ExponentialBackOff.Builder()
+ .setInitialIntervalMillis(INITIAL_RETRY_INTERVAL_MILLIS)
+ .setRandomizationFactor(RETRY_RANDOMIZATION_FACTOR)
+ .setMultiplier(RETRY_MULTIPLIER)
+ .build();
+
+ request.setUnsuccessfulResponseHandler(
+ new HttpBackOffUnsuccessfulResponseHandler(backoff)
+ .setBackOffRequired(BackOffRequired.ALWAYS));
+
  HttpResponse response = request.execute();
  jwks = response.parseAs(JsonWebKeySet.class);
  } catch (IOException io) {
@@ -589,7 +607,7 @@ public Map<String, PublicKey> load(String certificateUrl) throws Exception {
  "No valid public key returned by the keystore: " + certificateUrl);
  }
 
- return keyCacheBuilder.build();
+ return keyCache;
  }
 
  private PublicKey buildPublicKey(JsonWebKey key)

google-oauth-client/src/test/java/com/google/api/client/auth/openidconnect/IdTokenVerifierTest.java

@@ -68,9 +68,11 @@ public class IdTokenVerifierTest extends TestCase {
  "https://www.googleapis.com/oauth2/v1/certs";
 
  private static final String SERVICE_ACCOUNT_RS256_TOKEN =
- "eyJhbGciOiJSUzI1NiIsImtpZCI6IjJlZjc3YjM4YTFiMDM3MDQ4NzA0MzkxNmFjYmYyN2Q3NGVkZDA4YjEiLCJ0eXAiOiJKV1QifQ.eyJhdWQiOiJodHRwczovL2V4YW1wbGUuY29tL2F1ZGllbmNlIiwiZXhwIjoxNTg3NjMwNTQzLCJpYXQiOjE1ODc2MjY5NDMsImlzcyI6InNvbWUgaXNzdWVyIiwic3ViIjoic29tZSBzdWJqZWN0In0.gGOQW0qQgs4jGUmCsgRV83RqsJLaEy89-ZOG6p1u0Y26FyY06b6Odgd7xXLsSTiiSnch62dl0Lfi9D0x2ByxvsGOCbovmBl2ZZ0zHr1wpc4N0XS9lMUq5RJQbonDibxXG4nC2zroDfvD0h7i-L8KMXeJb9pYwW7LkmrM_YwYfJnWnZ4bpcsDjojmPeUBlACg7tjjOgBFbyQZvUtaERJwSRlaWibvNjof7eCVfZChE0PwBpZc_cGqSqKXv544L4ttqdCnmONjqrTATXwC4gYxruevkjHfYI5ojcQmXoWDJJ0-_jzfyPE4MFFdCFgzLgnfIOwe5ve0MtquKuv2O0pgvg";
+ "eyJhbGciOiJSUzI1NiIsImtpZCI6IjE3MjdiNmI0OTQwMmI5Y2Y5NWJlNGU4ZmQzOGFhN2U3YzExNjQ0YjEiLCJ0eXAiOiJKV1QifQ.eyJhdWQiOiJodHRwczovL2Nsb3VkdGFza3MuZ29vZ2xlYXBpcy5jb20vdjIvcHJvamVjdHMvZ2Nsb3VkLWRldmVsL2xvY2F0aW9ucyIsImF6cCI6InN0aW0tdGVzdEBzdGVsbGFyLWRheS0yNTQyMjIuaWFtLmdzZXJ2aWNlYWNjb3VudC5jb20iLCJlbWFpbCI6InN0aW0tdGVzdEBzdGVsbGFyLWRheS0yNTQyMjIuaWFtLmdzZXJ2aWNlYWNjb3VudC5jb20iLCJlbWFpbF92ZXJpZmllZCI6dHJ1ZSwiZXhwIjoxNjYwODgwNjczLCJpYXQiOjE2NjA4NzcwNzMsImlzcyI6Imh0dHBzOi8vYWNjb3VudHMuZ29vZ2xlLmNvbSIsInN1YiI6IjExMjgxMDY3Mjk2MzcyODM2NjQwNiJ9.Q2tG-hN6UHecbzaCIlg58K9msp58nLZWs03CBGO_D6F3cI4LKQEUzsbcztZqmNGWd0ld4zkrKzIP9cQosa_xold4hEzSX_ORRHYQLimLYaQmP3rKqWPMsbIupPdpnGqBDzAYjc7Pw9pQBzuZJj8e3FEG6a5tblDfMcgeklXZIkwzN7ypWCbFDoDP2STSYJYZ-LQIB0-Zlex7dm2KhyB8QSkMQK60YvpXz4L1OtwG7spk3yUCWxul6hYF76klST0iS6DH03YdaDpt4gRXkTUKyTRfB10h-WhCAKKRzmT6d_IT9ApIyqPhimkgkBHhLNyjK8lgAJdk9CLriSEOgVpsow";
+ private static final String SERVICE_ACCOUNT_RS256_TOKEN_BAD_SIGNATURE =
+ "eyJhbGciOiJSUzI1NiIsImtpZCI6IjE3MjdiNmI0OTQwMmI5Y2Y5NWJlNGU4ZmQzOGFhN2U3YzExNjQ0YjEiLCJ0eXAiOiJKV1QifQ.eyJhdWQiOiJodHRwczovL2Nsb3VkdGFza3MuZ29vZ2xlYXBpcy5jb20vdjIvcHJvamVjdHMvZ2Nsb3VkLWRldmVsL2xvY2F0aW9ucyIsImF6cCI6InN0aW0tdGVzdEBzdGVsbGFyLWRheS0yNTQyMjIuaWFtLmdzZXJ2aWNlYWNjb3VudC5jb20iLCJlbWFpbCI6InN0aW0tdGVzdEBzdGVsbGFyLWRheS0yNTQyMjIuaWFtLmdzZXJ2aWNlYWNjb3VudC5jb20iLCJlbWFpbF92ZXJpZmllZCI6dHJ1ZSwiZXhwIjoxNjYwODgwNjczLCJpYXQiOjE2NjA4NzcwNzMsImlzcyI6Imh0dHBzOi8vYWNjb3VudHMuZ29vZ2xlLmNvbSIsInN1YiI6IjExMjgxMDY3Mjk2MzcyODM2NjQwNiJ9.Q2tG-hN6UHecbzaCIlg58K9msp58nLZWs03CBGO_D6F3cI4LKQEUzsbcztZqmNGWd0ld4zkrKzIP9cQosa_xold4hEzSX_ORRHYQLimLYaQmP3rKqWPMsbIupPdpnGqBDzAYjc7Pw9pQBzuZJj8e3FEG6a5tblDfMcgeklXZIkwzN7ypWCbFDoDP2STSYJYZ-LQIB0-Zlex7dm2KhyB8QSkMQK60YvpXz4L1OtwG7spk3yUCWxul6hYF76klST0iS6DH03YdaDpt4gRXkTUKyTRfB10h-WhCAKKRzmT6d_IT9ApIyqPhimkgkBHhLNyjK8lgAJdk9CLriSEOgVpruy";
  private static final String SERVICE_ACCOUNT_CERT_URL =
- "https://www.googleapis.com/robot/v1/metadata/x509/integration-tests%40chingor-test.iam.gserviceaccount.com";
+ "https://www.googleapis.com/oauth2/v3/certs";
 
  private static final List<String> ALL_TOKENS =
  Arrays.asList(ES256_TOKEN, FEDERATED_SIGNON_RS256_TOKEN, SERVICE_ACCOUNT_RS256_TOKEN);
@@ -184,7 +186,7 @@ public void testBuilderSetNullIssuers() throws Exception {
  assertNull(verifier.getIssuer());
  }
 
- public void testMissingAudience() throws VerificationException {
+ public void testMissingAudience() throws IOException {
  IdToken idToken = newIdToken(ISSUER, null);
 
  MockClock clock = new MockClock();
@@ -198,7 +200,7 @@ public void testMissingAudience() throws VerificationException {
  assertFalse(verifier.verify(idToken));
  }
 
- public void testVerifyEs256TokenPublicKeyMismatch() throws Exception {
+ public void testPublicKeyStoreIntermittentError() throws Exception {
  // Mock HTTP requests
  MockLowLevelHttpRequest failedRequest =
  new MockLowLevelHttpRequest() {
@@ -245,7 +247,7 @@ public LowLevelHttpResponse execute() throws IOException {
  };
 
  HttpTransportFactory httpTransportFactory =
- mockTransport(failedRequest, badRequest, emptyRequest, goodRequest);
+ mockTransport(failedRequest, badRequest, badRequest, badRequest, emptyRequest, goodRequest);
  IdTokenVerifier tokenVerifier =
  new IdTokenVerifier.Builder()
  .setClock(FIXED_CLOCK)
@@ -255,28 +257,28 @@ public LowLevelHttpResponse execute() throws IOException {
  try {
  tokenVerifier.verifySignature(IdToken.parse(JSON_FACTORY, ES256_TOKEN));
  fail("Should have failed verification");
- } catch (VerificationException ex) {
+ } catch (IOException ex) {
  assertTrue(ex.getMessage().contains("Error fetching public key"));
  }
 
  try {
  tokenVerifier.verifySignature(IdToken.parse(JSON_FACTORY, ES256_TOKEN));
  fail("Should have failed verification");
- } catch (VerificationException ex) {
+ } catch (IOException ex) {
  assertTrue(ex.getMessage().contains("Error fetching public key"));
  }
 
  try {
  tokenVerifier.verifySignature(IdToken.parse(JSON_FACTORY, ES256_TOKEN));
  fail("Should have failed verification");
- } catch (VerificationException ex) {
+ } catch (IOException ex) {
  assertTrue(ex.getCause().getMessage().contains("No valid public key returned"));
  }
 
  Assert.assertTrue(tokenVerifier.verifySignature(IdToken.parse(JSON_FACTORY, ES256_TOKEN)));
  }
 
- public void testVerifyEs256Token() throws VerificationException, IOException {
+ public void testVerifyEs256Token() throws IOException {
  HttpTransportFactory httpTransportFactory =
  mockTransport(
  "https://www.gstatic.com/iap/verify/public_key-jwk",
@@ -289,7 +291,7 @@ public void testVerifyEs256Token() throws VerificationException, IOException {
  assertTrue(tokenVerifier.verify(IdToken.parse(JSON_FACTORY, ES256_TOKEN)));
  }
 
- public void testVerifyRs256Token() throws VerificationException, IOException {
+ public void testVerifyRs256Token() throws IOException {
  HttpTransportFactory httpTransportFactory =
  mockTransport(
  "https://www.googleapis.com/oauth2/v3/certs",
@@ -304,7 +306,7 @@ public void testVerifyRs256Token() throws VerificationException, IOException {
  }
 
  public void testVerifyRs256TokenWithLegacyCertificateUrlFormat()
- throws VerificationException, IOException {
+ throws IOException, VerificationException {
  HttpTransportFactory httpTransportFactory =
  mockTransport(
  LEGACY_FEDERATED_SIGNON_CERT_URL, readResourceAsString("legacy_federated_keys.json"));
@@ -318,15 +320,23 @@ public void testVerifyRs256TokenWithLegacyCertificateUrlFormat()
  assertTrue(tokenVerifier.verify(IdToken.parse(JSON_FACTORY, FEDERATED_SIGNON_RS256_TOKEN)));
  }
 
- public void testVerifyServiceAccountRs256Token() throws VerificationException, IOException {
- MockClock clock = new MockClock(1587626643000L);
+ public void testVerifyServiceAccountRs256Token() throws IOException {
+ MockClock clock = new MockClock(1660880973000L);
  IdTokenVerifier tokenVerifier =
  new IdTokenVerifier.Builder()
  .setClock(clock)
  .setCertificatesLocation(SERVICE_ACCOUNT_CERT_URL)
  .setHttpTransportFactory(new DefaultHttpTransportFactory())
  .build();
  assertTrue(tokenVerifier.verify(IdToken.parse(JSON_FACTORY, SERVICE_ACCOUNT_RS256_TOKEN)));
+
+ // a token with a bad signature that is expected to fail in verify, but work in verifyPayload
+ assertFalse(
+ tokenVerifier.verify(
+ IdToken.parse(JSON_FACTORY, SERVICE_ACCOUNT_RS256_TOKEN_BAD_SIGNATURE)));
+ assertTrue(
+ tokenVerifier.verifyPayload(
+ IdToken.parse(JSON_FACTORY, SERVICE_ACCOUNT_RS256_TOKEN_BAD_SIGNATURE)));
  }
 
  static String readResourceAsString(String resourceName) throws IOException {