firebase-ios-sdk/FirebaseAppCheck/Tests/Unit/AppAttestProvider/Storage/FIRAppAttestArtifactStorageTests.m

/*
 * Copyright 2021 Google LLC
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#import <XCTest/XCTest.h>

#import <OCMock/OCMock.h>

#import <GoogleUtilities/GULKeychainStorage.h>

#import "FBLPromise+Testing.h"

#import "FirebaseAppCheck/Sources/AppAttestProvider/Storage/FIRAppAttestArtifactStorage.h"
#import "FirebaseAppCheck/Sources/Core/Errors/FIRAppCheckErrorUtil.h"

@interface FIRAppAttestArtifactStorageTests : XCTestCase

@property(nonatomic) NSString *appName;
@property(nonatomic) NSString *appID;
@property(nonatomic) FIRAppAttestArtifactStorage *storage;

@end

@implementation FIRAppAttestArtifactStorageTests

- (void)setUp {
  [super setUp];

  self.appName = @"FIRAppAttestArtifactStorageTests";
  self.appID = @"1:100000000000:ios:aaaaaaaaaaaaaaaaaaaaaaaa";

  self.storage = [[FIRAppAttestArtifactStorage alloc] initWithAppName:self.appName
                                                                appID:self.appID
                                                          accessGroup:nil];
}

- (void)tearDown {
  self.storage = nil;
  [super tearDown];
}

#if !TARGET_OS_MACCATALYST  // Catalyst should be possible with Xcode 12.5+

- (void)testSetAndGetArtifact {
  [self assertSetGetForStorage];
}

- (void)testRemoveArtifact {
  NSString *keyID = [NSUUID UUID].UUIDString;

  // 1. Save an artifact to storage and check it is stored.
  [self assertSetGetForStorage];

  // 2. Remove artifact.
  __auto_type setPromise = [self.storage setArtifact:nil forKey:keyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertNil(setPromise.value);
  XCTAssertNil(setPromise.error);

  // 3. Check it has been removed.
  __auto_type getPromise = [self.storage getArtifactForKey:keyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertNil(getPromise.value);
  XCTAssertNil(getPromise.error);
}

- (void)testSetAndGetPerApp {
  // Assert storages for apps with the same name can independently set/get artifact.
  [self assertIndependentSetGetForStoragesWithAppName1:self.appName
                                                appID1:@"app_id"
                                              appName2:self.appName
                                                appID2:@"app_id_2"];
  // Assert storages for apps with the same app ID can independently set/get artifact.
  [self assertIndependentSetGetForStoragesWithAppName1:@"app_1"
                                                appID1:self.appID
                                              appName2:@"app_2"
                                                appID2:self.appID];
  // Assert storages for apps with different info can independently set/get artifact.
  [self assertIndependentSetGetForStoragesWithAppName1:@"app_1"
                                                appID1:@"app_id_1"
                                              appName2:@"app_2"
                                                appID2:@"app_id_2"];
}

- (void)testSetArtifactForOneKeyGetForAnotherKey {
  // Set an artifact for a key.
  [self assertSetGetForStorage];

  // Try to get artifact for a different key.
  NSString *keyID = [NSUUID UUID].UUIDString;
  __auto_type getPromise = [self.storage getArtifactForKey:keyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertNil(getPromise.value);
  XCTAssertNil(getPromise.error);
}

- (void)testSetArtifactForNewKeyRemovesArtifactForOldKey {
  // 1. Store an artifact.
  NSString *oldKeyID = [self assertSetGetForStorage];

  // 2. Replace the artifact.
  NSString *newKeyID = [self assertSetGetForStorage];
  XCTAssertNotEqualObjects(oldKeyID, newKeyID);

  // 3. Check old artifact was removed.
  __auto_type getPromise = [self.storage getArtifactForKey:oldKeyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertNil(getPromise.value);
  XCTAssertNil(getPromise.error);
}

- (void)testGetArtifact_KeychainError {
  // 1. Set up storage mock.
  id mockKeychainStorage = OCMClassMock([GULKeychainStorage class]);
  FIRAppAttestArtifactStorage *artifactStorage =
      [[FIRAppAttestArtifactStorage alloc] initWithAppName:self.appName
                                                     appID:self.appID
                                           keychainStorage:mockKeychainStorage
                                               accessGroup:nil];

  // 2. Create and expect keychain error.
  NSError *gulsKeychainError = [NSError errorWithDomain:@"com.guls.keychain" code:-1 userInfo:nil];
  OCMExpect([mockKeychainStorage getObjectForKey:[OCMArg any]
                                     objectClass:[OCMArg any]
                                     accessGroup:[OCMArg any]])
      .andReturn([FBLPromise resolvedWith:gulsKeychainError]);

  // 3. Get artifact and verify results.
  __auto_type getPromise = [artifactStorage getArtifactForKey:@"key"];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertNotNil(getPromise.error);
  XCTAssertEqualObjects(getPromise.error,
                        [FIRAppCheckErrorUtil keychainErrorWithError:gulsKeychainError]);

  // 4. Verify storage mock.
  OCMVerifyAll(mockKeychainStorage);
}

- (void)testSetArtifact_KeychainError {
  // 1. Set up storage mock.
  id mockKeychainStorage = OCMClassMock([GULKeychainStorage class]);
  FIRAppAttestArtifactStorage *artifactStorage =
      [[FIRAppAttestArtifactStorage alloc] initWithAppName:self.appName
                                                     appID:self.appID
                                           keychainStorage:mockKeychainStorage
                                               accessGroup:nil];
  // 2. Create and expect keychain error.
  NSError *gulsKeychainError = [NSError errorWithDomain:@"com.guls.keychain" code:-1 userInfo:nil];
  OCMExpect([mockKeychainStorage setObject:[OCMArg any]
                                    forKey:[OCMArg any]
                               accessGroup:[OCMArg any]])
      .andReturn([FBLPromise resolvedWith:gulsKeychainError]);

  // 3. Set artifact and verify results.
  NSData *artifact = [@"artifact" dataUsingEncoding:NSUTF8StringEncoding];
  __auto_type setPromise = [artifactStorage setArtifact:artifact forKey:@"key"];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertNotNil(setPromise.error);
  XCTAssertEqualObjects(setPromise.error,
                        [FIRAppCheckErrorUtil keychainErrorWithError:gulsKeychainError]);

  // 4. Verify storage mock.
  OCMVerifyAll(mockKeychainStorage);
}

- (void)testRemoveArtifact_KeychainError {
  // 1. Set up storage mock.
  id mockKeychainStorage = OCMClassMock([GULKeychainStorage class]);
  FIRAppAttestArtifactStorage *artifactStorage =
      [[FIRAppAttestArtifactStorage alloc] initWithAppName:self.appName
                                                     appID:self.appID
                                           keychainStorage:mockKeychainStorage
                                               accessGroup:nil];

  // 2. Create and expect keychain error.
  NSError *gulsKeychainError = [NSError errorWithDomain:@"com.guls.keychain" code:-1 userInfo:nil];
  OCMExpect([mockKeychainStorage removeObjectForKey:[OCMArg any] accessGroup:[OCMArg any]])
      .andReturn([FBLPromise resolvedWith:gulsKeychainError]);

  // 3. Remove artifact and verify results.
  __auto_type setPromise = [artifactStorage setArtifact:nil forKey:@"key"];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertNotNil(setPromise.error);
  XCTAssertEqualObjects(setPromise.error,
                        [FIRAppCheckErrorUtil keychainErrorWithError:gulsKeychainError]);

  // 4. Verify storage mock.
  OCMVerifyAll(mockKeychainStorage);
}

#pragma mark - Helpers

/// Sets a random artifact for a random key and asserts it can be read.
/// @return The random key ID used to set and get the artifact.
- (NSString *)assertSetGetForStorage {
  NSData *artifactToSet = [[NSUUID UUID].UUIDString dataUsingEncoding:NSUTF8StringEncoding];
  NSString *keyID = [NSUUID UUID].UUIDString;

  __auto_type setPromise = [self.storage setArtifact:artifactToSet forKey:keyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertEqualObjects(setPromise.value, artifactToSet);
  XCTAssertNil(setPromise.error);

  __auto_type getPromise = [self.storage getArtifactForKey:keyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertEqualObjects(getPromise.value, artifactToSet);
  XCTAssertNil(getPromise.error);

  __weak __auto_type weakSelf = self;
  [self addTeardownBlock:^{
    // Cleanup storage.
    [weakSelf.storage setArtifact:nil forKey:keyID];
    XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  }];

  return keyID;
}

- (void)assertIndependentSetGetForStoragesWithAppName1:(NSString *)appName1
                                                appID1:(NSString *)appID1
                                              appName2:(NSString *)appName2
                                                appID2:(NSString *)appID2 {
  NSString *keyID = [NSUUID UUID].UUIDString;

  // Create two storages.
  FIRAppAttestArtifactStorage *storage1 =
      [[FIRAppAttestArtifactStorage alloc] initWithAppName:appName1 appID:appID1 accessGroup:nil];
  FIRAppAttestArtifactStorage *storage2 =
      [[FIRAppAttestArtifactStorage alloc] initWithAppName:appName2 appID:appID2 accessGroup:nil];
  // 1. Independently set artifacts for the two storages.
  NSData *artifact1 = [@"app_attest_artifact1" dataUsingEncoding:NSUTF8StringEncoding];
  FBLPromise *setPromise1 = [storage1 setArtifact:artifact1 forKey:keyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertEqualObjects(setPromise1.value, artifact1);
  XCTAssertNil(setPromise1.error);

  NSData *artifact2 = [@"app_attest_artifact2" dataUsingEncoding:NSUTF8StringEncoding];
  __auto_type setPromise2 = [storage2 setArtifact:artifact2 forKey:keyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertEqualObjects(setPromise2.value, artifact2);
  XCTAssertNil(setPromise2.error);

  // 2. Get artifacts for the two storages.
  __auto_type getPromise1 = [storage1 getArtifactForKey:keyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertEqualObjects(getPromise1.value, artifact1);
  XCTAssertNil(getPromise1.error);

  __auto_type getPromise2 = [storage2 getArtifactForKey:keyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
  XCTAssertEqualObjects(getPromise2.value, artifact2);
  XCTAssertNil(getPromise2.error);

  // 3. Assert that artifacts were set and retrieved independently of one another.
  XCTAssertNotEqualObjects(getPromise1.value, getPromise2.value);

  // Cleanup storages.
  [storage1 setArtifact:nil forKey:keyID];
  [storage2 setArtifact:nil forKey:keyID];
  XCTAssert(FBLWaitForPromisesWithTimeout(0.5));
}
#endif  // !TARGET_OS_MACCATALYST

@end