feat: add snjs package

packages/snjs/lib/Services/Mfa/MfaService.ts

@@ -0,0 +1,68 @@
+import { SettingName } from '@standardnotes/settings'
+
+import { SNSettingsService } from '../Settings'
+import * as messages from '../Api/Messages'
+import { PureCryptoInterface } from '@standardnotes/sncrypto-common'
+import { SNFeaturesService } from '../Features/FeaturesService'
+import { FeatureIdentifier } from '@standardnotes/features'
+import { AbstractService, InternalEventBusInterface } from '@standardnotes/services'
+
+export class SNMfaService extends AbstractService {
+  constructor(
+    private settingsService: SNSettingsService,
+    private crypto: PureCryptoInterface,
+    private featuresService: SNFeaturesService,
+    protected override internalEventBus: InternalEventBusInterface,
+  ) {
+    super(internalEventBus)
+  }
+
+  private async saveMfaSetting(secret: string): Promise<void> {
+    return await this.settingsService.updateSetting(SettingName.MfaSecret, secret, true)
+  }
+
+  async isMfaActivated(): Promise<boolean> {
+    const mfaSetting = await this.settingsService.getDoesSensitiveSettingExist(SettingName.MfaSecret)
+    return mfaSetting != false
+  }
+
+  async generateMfaSecret(): Promise<string> {
+    return this.crypto.generateOtpSecret()
+  }
+
+  async getOtpToken(secret: string): Promise<string> {
+    return this.crypto.totpToken(secret, Date.now(), 6, 30)
+  }
+
+  async enableMfa(secret: string, otpToken: string): Promise<void> {
+    const otpTokenValid = otpToken != undefined && otpToken === (await this.getOtpToken(secret))
+
+    if (!otpTokenValid) {
+      throw new Error(messages.SignInStrings.IncorrectMfa)
+    }
+
+    return this.saveMfaSetting(secret)
+  }
+
+  async disableMfa(): Promise<void> {
+    return await this.settingsService.deleteSetting(SettingName.MfaSecret)
+  }
+
+  isMfaFeatureAvailable(): boolean {
+    const feature = this.featuresService.getUserFeature(FeatureIdentifier.TwoFactorAuth)
+
+    // If the feature is not present in the collection, we don't want to block it
+    if (feature == undefined) {
+      return false
+    }
+
+    return feature.no_expire === true || (feature.expires_at ?? 0) > Date.now()
+  }
+
+  override deinit(): void {
+    ;(this.settingsService as unknown) = undefined
+    ;(this.crypto as unknown) = undefined
+    ;(this.featuresService as unknown) = undefined
+    super.deinit()
+  }
+}