Add dh subsequence numbers

src/database/devicedhkey.ts

@@ -33,7 +33,7 @@ export function calculateExpireTime(now: bigint): BigInt {
   return expireTime
 }
 
-export interface DeviceDhKeyAttributes {
+interface DeviceDhKeyAttributesVersion1 {
   familyId: string
   deviceId: string
   version: string
@@ -43,12 +43,18 @@ export interface DeviceDhKeyAttributes {
   privateKey: Buffer
 }
 
+interface DeviceDhKeyAttributesVersion2 {
+  createdAtSubsequence: number
+}
+
+export type DeviceDhKeyAttributes = DeviceDhKeyAttributesVersion1 & DeviceDhKeyAttributesVersion2
+
 export type DeviceDhKeyModel = Sequelize.Model<DeviceDhKeyAttributes> & DeviceDhKeyAttributes
 export type DeviceDhKeyModelStatic = typeof Sequelize.Model & {
   new (values?: object, options?: Sequelize.BuildOptions): DeviceDhKeyModel;
 }
 
-export const attributes: SequelizeAttributes<DeviceDhKeyAttributes> = {
+export const attributesVersion1: SequelizeAttributes<DeviceDhKeyAttributesVersion1> = {
   familyId: {
     ...familyIdColumn,
     primaryKey: true
@@ -78,4 +84,17 @@ export const attributes: SequelizeAttributes<DeviceDhKeyAttributes> = {
   }
 }
 
+export const attributesVersion2: SequelizeAttributes<DeviceDhKeyAttributesVersion2> = {
+  createdAtSubsequence: {
+    type: Sequelize.INTEGER,
+    allowNull: false,
+    defaultValue: 0
+  }
+}
+
+export const attributes: SequelizeAttributes<DeviceDhKeyAttributes> = {
+  ...attributesVersion1,
+  ...attributesVersion2
+}
+
 export const createDeviceDhKey = (sequelize: Sequelize.Sequelize): DeviceDhKeyModelStatic => sequelize.define('DeviceDhKey', attributes) as DeviceDhKeyModelStatic

src/database/migration/migrations/20220921-add-dh-subsequence.ts

@@ -0,0 +1,39 @@
+/*
+ * server component for the TimeLimit App
+ * Copyright (C) 2019 - 2022 Jonas Lochmann
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, version 3 of the License.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+import { QueryInterface, Sequelize, Transaction } from 'sequelize'
+import { attributesVersion2 as dhKeyAttributes } from '../../devicedhkey'
+
+export async function up (queryInterface: QueryInterface, sequelize: Sequelize) {
+  await sequelize.transaction({
+    type: Transaction.TYPES.EXCLUSIVE
+  }, async (transaction) => {
+    await queryInterface.addColumn('DeviceDhKeys', 'createdAtSubsequence', {
+      ...dhKeyAttributes.createdAtSubsequence
+    }, {
+      transaction
+    })
+  })
+}
+
+export async function down (queryInterface: QueryInterface, sequelize: Sequelize) {
+  await sequelize.transaction({
+    type: Transaction.TYPES.EXCLUSIVE
+  }, async (transaction) => {
+    await queryInterface.removeColumn('DeviceDhKeys', 'createdAtSubsequence', { transaction })
+  })
+}

src/function/sync/get-server-data-status/dh-keys.ts

@@ -58,18 +58,30 @@ export async function getDeviceDhKeys ({
     if (savedData.length >= 8) {
       eventHandler.countEvent('getDeviceDhKeys:gc')
 
-      const minCreatedAtValue = savedData.map((item) => BigInt(item.createdAt)).sort()[0]
+      const elementToRemove = savedData.reduce((a, currentItem, currentIndex) => {
+        const b = { item: currentItem, index: currentIndex }
+
+        const createdA = BigInt(a.item.createdAt)
+        const createdB = BigInt(b.item.createdAt)
+
+        if (createdA > createdB) return b
+        else if (createdA < createdB) return a
+        else {
+          if (a.item.createdAtSubsequence > b.item.createdAtSubsequence) return b
+          else return a
+        }
+      }, { index: 0, item: savedData[0] })
 
       await database.deviceDhKey.destroy({
         where: {
           familyId: familyEntry.familyId,
           deviceId,
-          createdAt: {
-            [Sequelize.Op.lte]: minCreatedAtValue.toString(10)
-          }
+          version: elementToRemove.item.version
         },
         transaction
       })
+
+      savedData.splice(elementToRemove.index, 1)
     }
 
     await database.deviceDhKey.update({
@@ -83,11 +95,22 @@ export async function getDeviceDhKeys ({
       transaction
     })
 
+    const newItemCreatedAt = (now - now % BigInt(config.generationTimeRounding))
+
+    const newItemExistingSubsequenceValues =
+      savedData
+        .filter((item) => BigInt(item.createdAt) === newItemCreatedAt)
+        .map((item) => item.createdAtSubsequence)
+
+    const newItemCreatedAtSubsequence =
+      newItemExistingSubsequenceValues.reduce((max, item) => Math.max(max, item + 1), 0)
+
     await database.deviceDhKey.create({
       familyId: familyEntry.familyId,
       deviceId,
       version: newVersion,
-      createdAt: (now - now % BigInt(config.generationTimeRounding)).toString(10),
+      createdAt: newItemCreatedAt.toString(10),
+      createdAtSubsequence: Math.min(newItemCreatedAtSubsequence, 1 << 30),
       expireAt: null,
       publicKey: newKeypair.publicKey,
       privateKey: newKeypair.privateKey