Desktop/ts/test-electron/backup/filePointer_test.preload.ts

// Copyright 2024 Signal Messenger, LLC
// SPDX-License-Identifier: AGPL-3.0-only
import { assert } from 'chai';
import * as sinon from 'sinon';
import { BackupLevel } from '@signalapp/libsignal-client/zkgroup.js';
import { randomBytes } from 'node:crypto';
import { join } from 'node:path';
import { emptyDir, ensureFile } from 'fs-extra';

import type { Backups } from '../../protobuf/index.std.js';

import {
  getFilePointerForAttachment,
  convertFilePointerToAttachment,
} from '../../services/backups/util/filePointers.preload.js';
import { IMAGE_PNG } from '../../types/MIME.std.js';
import * as Bytes from '../../Bytes.std.js';
import type { AttachmentType } from '../../types/Attachment.std.js';
import { MASTER_KEY, MEDIA_ROOT_KEY } from './helpers.preload.js';
import { generateKeys } from '../../AttachmentCrypto.node.js';
import type { GetBackupCdnInfoType } from '../../services/backups/util/mediaId.preload.js';
import { strictAssert } from '../../util/assert.std.js';
import { isValidAttachmentKey } from '../../types/Crypto.std.js';
import { itemStorage } from '../../textsecure/Storage.preload.js';
import { getAbsoluteAttachmentPath } from '../../util/migrations.preload.js';
import { getAttachmentsPath } from '../../../app/attachments.node.js';
import { sha256 } from '../../Crypto.node.js';

describe('convertFilePointerToAttachment', () => {
  const commonFilePointerProps = {
    $unknown: [],
    contentType: 'image/png',
    width: 100,
    height: 100,
    blurHash: 'blurhash',
    fileName: 'filename',
    caption: 'caption',
    incrementalMac: Bytes.fromString('incrementalMac'),
    incrementalMacChunkSize: 1000,
    locatorInfo: null,
  };
  const commonAttachmentProps = {
    contentType: IMAGE_PNG,
    width: 100,
    height: 100,
    blurHash: 'blurhash',
    fileName: 'filename',
    caption: 'caption',
    incrementalMac: Bytes.toBase64(Bytes.fromString('incrementalMac')),
    chunkSize: 1000,
  } as const;

  describe('locatorInfo', () => {
    it('processes filepointer with empty locatorInfo', () => {
      const result = convertFilePointerToAttachment(
        {
          ...commonFilePointerProps,
          locatorInfo: null,
        },
        { type: 'remote' },
        { _createName: () => 'downloadPath' }
      );

      assert.deepStrictEqual(result, {
        ...commonAttachmentProps,
        size: 0,
        error: true,
        downloadPath: undefined,
      });
    });
    it('processes filepointer with missing locatorInfo', () => {
      const result = convertFilePointerToAttachment(
        commonFilePointerProps,
        { type: 'remote' },
        { _createName: () => 'downloadPath' }
      );

      assert.deepStrictEqual(result, {
        ...commonAttachmentProps,
        size: 0,
        error: true,
        downloadPath: undefined,
      });
    });

    it('processes locatorInfo with plaintextHash', () => {
      const result = convertFilePointerToAttachment(
        {
          ...commonFilePointerProps,
          locatorInfo: {
            $unknown: [],
            transitCdnKey: 'cdnKey',
            transitCdnNumber: 42,
            size: 128,
            transitTierUploadTimestamp: 12345n,
            key: Bytes.fromString('key'),
            integrityCheck: {
              plaintextHash: Bytes.fromString('plaintextHash'),
            },
            mediaTierCdnNumber: 43,
            localKey: null,
          },
        },
        { type: 'remote' },
        { _createName: () => 'downloadPath' }
      );

      assert.deepStrictEqual(result, {
        ...commonAttachmentProps,
        size: 128,
        cdnKey: 'cdnKey',
        cdnNumber: 42,
        downloadPath: 'downloadPath',
        digest: undefined,
        key: Bytes.toBase64(Bytes.fromString('key')),
        uploadTimestamp: 12345,
        backupCdnNumber: 43,
        plaintextHash: Bytes.toHex(Bytes.fromString('plaintextHash')),
        localBackupPath: undefined,
        localKey: undefined,
      });
    });
    it('processes locatorInfo with localKey', () => {
      const result = convertFilePointerToAttachment(
        {
          ...commonFilePointerProps,
          locatorInfo: {
            $unknown: [],
            transitCdnKey: 'cdnKey',
            transitCdnNumber: 42,
            size: 128,
            transitTierUploadTimestamp: 12345n,
            key: Bytes.fromString('key'),
            integrityCheck: {
              plaintextHash: Bytes.fromString('plaintextHash'),
            },
            mediaTierCdnNumber: 43,
            localKey: Bytes.fromString('localKey'),
          },
        },
        { type: 'local-encrypted', localBackupSnapshotDir: '/root/backups' },
        {
          _createName: () => 'downloadPath',
        }
      );

      const mediaName = Bytes.toHex(
        sha256(
          Bytes.concatenate([
            Bytes.fromString('plaintextHash'),
            Bytes.fromString('localKey'),
          ])
        )
      );
      assert.deepStrictEqual(result, {
        ...commonAttachmentProps,
        size: 128,
        cdnKey: 'cdnKey',
        cdnNumber: 42,
        downloadPath: 'downloadPath',
        key: Bytes.toBase64(Bytes.fromString('key')),
        digest: undefined,
        uploadTimestamp: 12345,
        backupCdnNumber: 43,
        plaintextHash: Bytes.toHex(Bytes.fromString('plaintextHash')),
        localBackupPath: join(
          '/',
          'root',
          'files',
          mediaName.slice(0, 2),
          mediaName
        ),
        localKey: Bytes.toBase64(Bytes.fromString('localKey')),
      });
    });
  });
});

const defaultAttachment = {
  size: 100,
  contentType: IMAGE_PNG,
  cdnKey: 'cdnKey',
  cdnNumber: 2,
  path: 'path/to/file.png',
  key: Bytes.toBase64(randomBytes(64)),
  digest: Bytes.toBase64(randomBytes(32)),
  plaintextHash: Bytes.toHex(randomBytes(32)),
  backupCdnNumber: 42,
  width: 100,
  height: 100,
  blurHash: 'blurhash',
  fileName: 'filename',
  caption: 'caption',
  incrementalMac: 'incrementalMac',
  chunkSize: 1000,
  uploadTimestamp: 1234,
  localKey: Bytes.toBase64(generateKeys()),
  version: 2,
} as const satisfies AttachmentType;

const defaultMediaName = Bytes.toHex(
  Bytes.concatenate([
    Bytes.fromHex(defaultAttachment.plaintextHash),
    Bytes.fromBase64(defaultAttachment.key),
  ])
);

const defaultFilePointer: Backups.FilePointer.Params = {
  contentType: IMAGE_PNG,
  width: 100,
  height: 100,
  blurHash: 'blurhash',
  fileName: 'filename',
  caption: 'caption',
  incrementalMac: Bytes.fromBase64('incrementalMac'),
  incrementalMacChunkSize: 1000,
  locatorInfo: null,
};

const notInBackupCdn: GetBackupCdnInfoType = async () => {
  return { isInBackupTier: false };
};
describe('getFilePointerForAttachment', () => {
  let sandbox: sinon.SinonSandbox;

  beforeEach(async () => {
    sandbox = sinon.createSandbox();
    sandbox.stub(itemStorage, 'get').callsFake(key => {
      if (key === 'masterKey') {
        return MASTER_KEY;
      }
      if (key === 'backupMediaRootKey') {
        return MEDIA_ROOT_KEY;
      }
      return undefined;
    });
    await ensureFile(getAbsoluteAttachmentPath(defaultAttachment.path));
  });

  afterEach(async () => {
    sandbox.restore();
    await emptyDir(
      getAttachmentsPath(window.SignalContext.config.userDataPath)
    );
  });

  it('if missing key, generates a new one and removes transit info & digest', async () => {
    const { filePointer } = await getFilePointerForAttachment({
      attachment: { ...defaultAttachment, key: undefined },
      backupOptions: {
        type: 'remote',
        level: BackupLevel.Paid,
        abortSignal: new AbortController().signal,
      },
      getBackupCdnInfo: notInBackupCdn,
      messageReceivedAt: 100,
    });

    const key = filePointer.locatorInfo?.key;

    strictAssert(key, 'key exists');
    assert.isTrue(isValidAttachmentKey(Bytes.toBase64(key)));

    assert.deepStrictEqual(filePointer, {
      ...defaultFilePointer,
      locatorInfo: {
        size: 100,
        integrityCheck: {
          plaintextHash: Bytes.fromHex(defaultAttachment.plaintextHash),
        },
        key: filePointer.locatorInfo?.key ?? null,
        transitCdnKey: null,
        transitCdnNumber: null,
        transitTierUploadTimestamp: null,
        mediaTierCdnNumber: null,
        localKey: null,
      },
    });
  });

  it('includes transit cdn info', async () => {
    assert.deepEqual(
      await getFilePointerForAttachment({
        attachment: { ...defaultAttachment, plaintextHash: undefined },
        backupOptions: {
          type: 'remote',
          level: BackupLevel.Paid,
          abortSignal: new AbortController().signal,
        },
        getBackupCdnInfo: notInBackupCdn,
        messageReceivedAt: 100,
      }),
      {
        filePointer: {
          ...defaultFilePointer,
          locatorInfo: {
            integrityCheck: {
              encryptedDigest: Bytes.fromBase64(defaultAttachment.digest),
            },
            key: Bytes.fromBase64(defaultAttachment.key),
            size: 100,
            transitCdnKey: 'cdnKey',
            transitCdnNumber: 2,
            transitTierUploadTimestamp: 1234n,
            mediaTierCdnNumber: null,
            localKey: null,
          },
        },
        backupJob: undefined,
      }
    );
  });
  it('includes transit cdn and backup info', async () => {
    assert.deepEqual(
      await getFilePointerForAttachment({
        attachment: defaultAttachment,
        backupOptions: {
          type: 'remote',
          level: BackupLevel.Free,
          abortSignal: new AbortController().signal,
        },
        getBackupCdnInfo: notInBackupCdn,
        messageReceivedAt: 100,
      }),
      {
        filePointer: {
          ...defaultFilePointer,
          locatorInfo: {
            integrityCheck: {
              plaintextHash: Bytes.fromHex(defaultAttachment.plaintextHash),
            },
            key: Bytes.fromBase64(defaultAttachment.key),
            size: 100,
            transitCdnKey: 'cdnKey',
            transitCdnNumber: 2,
            transitTierUploadTimestamp: 1234n,
            mediaTierCdnNumber: null,
            localKey: null,
          },
        },
        backupJob: undefined,
      }
    );
  });

  it('includes transit cdn and backup info even if digest is missing', async () => {
    assert.deepEqual(
      await getFilePointerForAttachment({
        attachment: { ...defaultAttachment, digest: undefined },
        backupOptions: {
          type: 'remote',
          level: BackupLevel.Free,
          abortSignal: new AbortController().signal,
        },
        getBackupCdnInfo: notInBackupCdn,
        messageReceivedAt: 100,
      }),
      {
        filePointer: {
          ...defaultFilePointer,
          locatorInfo: {
            integrityCheck: {
              plaintextHash: Bytes.fromHex(defaultAttachment.plaintextHash),
            },
            key: Bytes.fromBase64(defaultAttachment.key),
            size: 100,
            transitCdnKey: 'cdnKey',
            transitCdnNumber: 2,
            transitTierUploadTimestamp: 1234n,
            mediaTierCdnNumber: null,
            localKey: null,
          },
        },
        backupJob: undefined,
      }
    );
  });

  it('includes backup info even if transit tier info is missing', async () => {
    assert.deepEqual(
      await getFilePointerForAttachment({
        attachment: { ...defaultAttachment, cdnKey: undefined },
        backupOptions: {
          type: 'remote',
          level: BackupLevel.Free,
          abortSignal: new AbortController().signal,
        },
        getBackupCdnInfo: notInBackupCdn,
        messageReceivedAt: 100,
      }),
      {
        filePointer: {
          ...defaultFilePointer,
          locatorInfo: {
            integrityCheck: {
              plaintextHash: Bytes.fromHex(defaultAttachment.plaintextHash),
            },
            key: Bytes.fromBase64(defaultAttachment.key),
            size: 100,
            transitCdnKey: null,
            transitCdnNumber: null,
            transitTierUploadTimestamp: null,
            mediaTierCdnNumber: null,
            localKey: null,
          },
        },
        backupJob: undefined,
      }
    );
  });
  it('includes backup job if paid tier', async () => {
    assert.deepEqual(
      await getFilePointerForAttachment({
        attachment: defaultAttachment,
        backupOptions: {
          type: 'remote',
          level: BackupLevel.Paid,
          abortSignal: new AbortController().signal,
        },
        getBackupCdnInfo: notInBackupCdn,
        messageReceivedAt: 100,
      }),
      {
        filePointer: {
          ...defaultFilePointer,
          locatorInfo: {
            integrityCheck: {
              plaintextHash: Bytes.fromHex(defaultAttachment.plaintextHash),
            },
            key: Bytes.fromBase64(defaultAttachment.key),
            size: 100,
            transitCdnKey: 'cdnKey',
            transitCdnNumber: 2,
            transitTierUploadTimestamp: 1234n,
            mediaTierCdnNumber: null,
            localKey: null,
          },
        },
        backupJob: {
          data: {
            contentType: defaultAttachment.contentType,
            keys: defaultAttachment.key,
            localKey: defaultAttachment.localKey,
            path: defaultAttachment.path,
            size: defaultAttachment.size,
            transitCdnInfo: {
              cdnKey: defaultAttachment.cdnKey,
              cdnNumber: defaultAttachment.cdnNumber,
              uploadTimestamp: defaultAttachment.uploadTimestamp,
            },
            version: 2,
          },
          mediaName: defaultMediaName,
          receivedAt: 100,
          type: 'standard',
        },
      }
    );
  });
  it('does not include backup job if file does not exist', async () => {
    assert.deepEqual(
      await getFilePointerForAttachment({
        attachment: { ...defaultAttachment, path: 'not/here' },
        backupOptions: {
          type: 'remote',
          level: BackupLevel.Paid,
          abortSignal: new AbortController().signal,
        },
        getBackupCdnInfo: notInBackupCdn,
        messageReceivedAt: 100,
      }),
      {
        filePointer: {
          ...defaultFilePointer,
          locatorInfo: {
            integrityCheck: {
              plaintextHash: Bytes.fromHex(defaultAttachment.plaintextHash),
            },
            key: Bytes.fromBase64(defaultAttachment.key),
            size: 100,
            transitCdnKey: 'cdnKey',
            transitCdnNumber: 2,
            transitTierUploadTimestamp: 1234n,
            mediaTierCdnNumber: null,
            localKey: null,
          },
        },
        backupJob: undefined,
      }
    );
  });
  describe('local backups', () => {
    const defaultLocalMediaName = Bytes.toHex(
      sha256(
        Bytes.concatenate([
          Bytes.fromHex(defaultAttachment.plaintextHash),
          Bytes.fromBase64(defaultAttachment.localKey),
        ])
      )
    );

    it('generates local backup locatorInfo and a local backup job', async () => {
      assert.deepEqual(
        await getFilePointerForAttachment({
          attachment: defaultAttachment,
          backupOptions: {
            type: 'local-encrypted',
            abortSignal: new AbortController().signal,
          },
          getBackupCdnInfo: notInBackupCdn,
          messageReceivedAt: 100,
        }),
        {
          filePointer: {
            ...defaultFilePointer,
            locatorInfo: {
              integrityCheck: {
                plaintextHash: Bytes.fromHex(defaultAttachment.plaintextHash),
              },
              localKey: Bytes.fromBase64(defaultAttachment.localKey),
              key: Bytes.fromBase64(defaultAttachment.key),
              size: 100,
              transitCdnKey: 'cdnKey',
              transitCdnNumber: 2,
              transitTierUploadTimestamp: 1234n,
              mediaTierCdnNumber: null,
            },
          },
          backupJob: {
            isPlaintextExport: false,
            data: {
              contentType: defaultAttachment.contentType,
              fileName: defaultAttachment.fileName,
              localKey: defaultAttachment.localKey,
              path: defaultAttachment.path,
              size: defaultAttachment.size,
            },
            mediaName: defaultLocalMediaName,
            type: 'local',
          },
        }
      );
    });
    it('if file does not exist, does not include localKey or backup job', async () => {
      assert.deepEqual(
        await getFilePointerForAttachment({
          attachment: { ...defaultAttachment, path: 'no/file/here' },
          backupOptions: {
            type: 'local-encrypted',
            abortSignal: new AbortController().signal,
          },
          getBackupCdnInfo: notInBackupCdn,
          messageReceivedAt: 100,
        }),
        {
          filePointer: {
            ...defaultFilePointer,
            locatorInfo: {
              integrityCheck: {
                plaintextHash: Bytes.fromHex(defaultAttachment.plaintextHash),
              },
              key: Bytes.fromBase64(defaultAttachment.key),
              size: 100,
              transitCdnKey: 'cdnKey',
              transitCdnNumber: 2,
              transitTierUploadTimestamp: 1234n,
              mediaTierCdnNumber: null,
              localKey: null,
            },
          },
          backupJob: undefined,
        }
      );
    });
  });
});