Store hotlink access token hash on upload for short URL lookup.

backend/src/database/migrations/1791230839248-add-upload-hotlink-access-token-hash.ts

@@ -0,0 +1,19 @@
+import { MigrationInterface, QueryRunner } from 'typeorm';
+
+export class AddUploadHotlinkAccessTokenHash1791230839248 implements MigrationInterface {
+    name = 'AddUploadHotlinkAccessTokenHash1791230839248';
+
+    public async up(queryRunner: QueryRunner): Promise<void> {
+        await queryRunner.query(`ALTER TABLE "upload_hotlink" ADD "accessTokenHash" character varying(64)`);
+        await queryRunner.query(
+            `ALTER TABLE "upload_hotlink" ADD CONSTRAINT "UQ_upload_hotlink_accessTokenHash" UNIQUE ("accessTokenHash")`
+        );
+    }
+
+    public async down(queryRunner: QueryRunner): Promise<void> {
+        await queryRunner.query(
+            `ALTER TABLE "upload_hotlink" DROP CONSTRAINT "UQ_upload_hotlink_accessTokenHash"`
+        );
+        await queryRunner.query(`ALTER TABLE "upload_hotlink" DROP COLUMN "accessTokenHash"`);
+    }
+}

backend/src/modules/upload/dto/CreateHotlinkUploadDto.ts

@@ -1,8 +1,13 @@
-import { IsNotEmpty, IsString } from 'class-validator';
+import { IsHash, IsNotEmpty, IsString } from 'class-validator';
 import { IsImageMimeType } from '../../../validation/decorators/isImageMimeType';
 import { UploadCiphertextOptionsDto } from './UploadCiphertextOptionsDto';
 
 export class CreateHotlinkUploadDto extends UploadCiphertextOptionsDto {
+    @IsNotEmpty()
+    @IsString()
+    @IsHash('sha256')
+    accessTokenHash: string;
+
     @IsNotEmpty()
     @IsString()
     @IsImageMimeType()

backend/src/modules/upload/entities/UploadHotlink.ts

@@ -1,7 +1,8 @@
-import { Column, Entity, JoinColumn, OneToOne, PrimaryGeneratedColumn } from 'typeorm';
+import { Column, Entity, JoinColumn, OneToOne, PrimaryGeneratedColumn, Unique } from 'typeorm';
 import { Upload } from './Upload';
 
 @Entity('upload_hotlink')
+@Unique('UQ_upload_hotlink_accessTokenHash', ['accessTokenHash'])
 export class UploadHotlink {
     @PrimaryGeneratedColumn('uuid')
     id: string;
@@ -9,6 +10,9 @@ export class UploadHotlink {
     @Column()
     mimeType: string;
 
+    @Column({ type: 'varchar', length: 64, nullable: true })
+    accessTokenHash: string | null;
+
     @OneToOne(() => Upload, upload => upload.hotlink, { onDelete: 'CASCADE' })
     @JoinColumn()
     upload: Upload;

backend/src/modules/upload/services/UploadService.spec.ts

@@ -1,6 +1,7 @@
 import { BadRequestException, NotFoundException } from '@nestjs/common';
 import { createCipheriv, randomBytes } from 'node:crypto';
 import { hashDeleteToken } from '../../../utils/hashDeleteToken';
+import { hashHotlinkAccessToken } from '../../../utils/hashHotlinkAccessToken';
 import { AES_GCM_IV_BYTE_LENGTH } from '../../../consts/crypto/aesGcmIvByteLength';
 import type { DataSource, EntityManager, Repository } from 'typeorm';
 import type { Upload } from '../entities/Upload';
@@ -46,6 +47,9 @@ const encryptHotlinkCiphertext = (plaintext: Buffer, key: Buffer, iv: Buffer): B
     return Buffer.concat([cipher.update(plaintext), cipher.final(), cipher.getAuthTag()]);
 };
 
+const fixedAccessToken = Buffer.alloc(32, 0xcd).toString('base64url');
+const fixedAccessTokenHash = hashHotlinkAccessToken(fixedAccessToken);
+
 describe('UploadService', () => {
     let service: UploadService;
     let dataSource: jest.Mocked<Pick<DataSource, 'transaction'>>;
@@ -111,7 +115,8 @@ describe('UploadService', () => {
                 ciphertext,
                 expiresAt: null,
                 maxViews: null,
-                mimeType: 'image/png'
+                mimeType: 'image/png',
+                accessTokenHash: fixedAccessTokenHash
             });
 
             expect(result).toEqual({
@@ -128,7 +133,7 @@ describe('UploadService', () => {
                 maxViews: null,
                 deleteTokenHash: hashDeleteToken(deleteToken),
                 expiresAt: null,
-                hotlink: { mimeType: 'image/png' }
+                hotlink: { mimeType: 'image/png', accessTokenHash: fixedAccessTokenHash }
             });
             expect(uploadRepository.save).toHaveBeenCalledTimes(1);
             expect(storageService.write).toHaveBeenCalledWith(fixedId, ciphertextBuffer);
@@ -202,7 +207,8 @@ describe('UploadService', () => {
                     ciphertext: ciphertextBase64(0xff),
                     expiresAt: null,
                     maxViews: null,
-                    mimeType: 'image/jpeg'
+                    mimeType: 'image/jpeg',
+                    accessTokenHash: fixedAccessTokenHash
                 })
             ).rejects.toThrow(BadRequestException);
 
@@ -520,7 +526,8 @@ describe('UploadService', () => {
                     ciphertext: ciphertextBase64(),
                     expiresAt: null,
                     maxViews: null,
-                    mimeType: 'image/png'
+                    mimeType: 'image/png',
+                    accessTokenHash: fixedAccessTokenHash
                 })
             ).rejects.toThrow('disk full');
 

backend/src/modules/upload/services/UploadService.ts

@@ -83,7 +83,8 @@ export class UploadService {
         ciphertext,
         expiresAt,
         maxViews,
-        mimeType
+        mimeType,
+        accessTokenHash
     }: CreateHotlinkUploadDto): Promise<CreatedUploadResult> {
         const ciphertextBuffer = fromBase64(ciphertext);
 
@@ -104,7 +105,7 @@ export class UploadService {
                 maxViews,
                 deleteTokenHash: hashDeleteToken(deleteToken),
                 expiresAt,
-                hotlink: { mimeType }
+                hotlink: { mimeType, accessTokenHash }
             });
 
             await uploadRepository.save(upload);

backend/src/utils/hashHotlinkAccessToken.spec.ts

@@ -0,0 +1,12 @@
+import { createHash } from 'node:crypto';
+import { hashHotlinkAccessToken } from './hashHotlinkAccessToken';
+
+describe('hashHotlinkAccessToken', () => {
+    it('matches sha256 hex digest of the utf8 access token string', () => {
+        const accessToken = 'test-hotlink-access-token_base64url';
+
+        expect(hashHotlinkAccessToken(accessToken)).toBe(
+            createHash('sha256').update(accessToken, 'utf8').digest('hex')
+        );
+    });
+});

backend/src/utils/hashHotlinkAccessToken.ts

@@ -0,0 +1,4 @@
+import { createHash } from 'node:crypto';
+
+export const hashHotlinkAccessToken = (accessToken: string): string =>
+    createHash('sha256').update(accessToken, 'utf8').digest('hex');