스트리밍 방식으로 동영상을 불러올 때 다운로드 메뉴가 표시되지 않는 버그 수정

.dockerignore

@@ -12,6 +12,7 @@ node_modules
 /data
 /library
 /thumbnails
+/uploads
 
 # OS
 .DS_Store

.env.example

@@ -12,3 +12,4 @@ USER_CLIENT_CHALLENGE_EXPIRES=
 SESSION_UPGRADE_CHALLENGE_EXPIRES=
 LIBRARY_PATH=
 THUMBNAILS_PATH=
+UPLOADS_PATH=

.gitignore

@@ -10,6 +10,7 @@ node_modules
 /data
 /library
 /thumbnails
+/uploads
 
 # OS
 .DS_Store

docker-compose.yaml

@@ -20,6 +20,7 @@ services:
       - SESSION_UPGRADE_CHALLENGE_EXPIRES
       - LIBRARY_PATH=/app/data/library
       - THUMBNAILS_PATH=/app/data/thumbnails
+      - UPLOADS_PATH=/app/data/uploads
       # SvelteKit
       - ADDRESS_HEADER=${TRUST_PROXY:+X-Forwarded-For}
       - XFF_DEPTH=${TRUST_PROXY:-}

src/hooks.client.ts

@@ -1,7 +1,6 @@
 import type { ClientInit } from "@sveltejs/kit";
 import { cleanupDanglingInfos, getClientKey, getMasterKeys, getHmacSecrets } from "$lib/indexedDB";
 import { prepareFileCache } from "$lib/modules/file";
-import { prepareOpfs } from "$lib/modules/opfs";
 import { clientKeyStore, masterKeyStore, hmacSecretStore } from "$lib/stores";
 
 const requestPersistentStorage = async () => {
@@ -46,7 +45,6 @@ export const init: ClientInit = async () => {
     prepareClientKeyStore(),
     prepareMasterKeyStore(),
     prepareHmacSecretStore(),
-    prepareOpfs(),
   ]);
 
   cleanupDanglingInfos(); // Intended

src/hooks.server.ts

@@ -7,6 +7,7 @@ import {
   cleanupExpiredSessions,
   cleanupExpiredSessionUpgradeChallenges,
 } from "$lib/server/db/session";
+import { cleanupExpiredUploadSessions } from "$lib/server/db/upload";
 import { authenticate, setAgentInfo } from "$lib/server/middlewares";
 
 export const init: ServerInit = async () => {
@@ -16,6 +17,7 @@ export const init: ServerInit = async () => {
     cleanupExpiredUserClientChallenges();
     cleanupExpiredSessions();
     cleanupExpiredSessionUpgradeChallenges();
+    cleanupExpiredUploadSessions();
   });
 };
 

src/lib/constants/index.ts

@@ -0,0 +1,2 @@
+export * from "./serviceWorker";
+export * from "./upload";

src/lib/constants/serviceWorker.ts

@@ -0,0 +1 @@
+export const DECRYPTED_FILE_URL_PREFIX = "/_internal/decrypted-file/";

src/lib/constants/upload.ts

@@ -0,0 +1,6 @@
+export const AES_GCM_IV_SIZE = 12;
+export const AES_GCM_TAG_SIZE = 16;
+export const ENCRYPTION_OVERHEAD = AES_GCM_IV_SIZE + AES_GCM_TAG_SIZE;
+
+export const CHUNK_SIZE = 4 * 1024 * 1024;
+export const ENCRYPTED_CHUNK_SIZE = CHUNK_SIZE + ENCRYPTION_OVERHEAD;

src/lib/modules/crypto/aes.ts

@@ -1,8 +1,15 @@
-import { encodeString, decodeString, encodeToBase64, decodeFromBase64 } from "./util";
+import { AES_GCM_IV_SIZE } from "$lib/constants";
+import {
+  encodeString,
+  decodeString,
+  encodeToBase64,
+  decodeFromBase64,
+  concatenateBuffers,
+} from "./util";
 
 export const generateMasterKey = async () => {
   return {
-    masterKey: await window.crypto.subtle.generateKey(
+    masterKey: await crypto.subtle.generateKey(
       {
         name: "AES-KW",
         length: 256,
@@ -15,7 +22,7 @@ export const generateMasterKey = async () => {
 
 export const generateDataKey = async () => {
   return {
-    dataKey: await window.crypto.subtle.generateKey(
+    dataKey: await crypto.subtle.generateKey(
       {
         name: "AES-GCM",
         length: 256,
@@ -28,9 +35,9 @@ export const generateDataKey = async () => {
 };
 
 export const makeAESKeyNonextractable = async (key: CryptoKey) => {
-  return await window.crypto.subtle.importKey(
+  return await crypto.subtle.importKey(
     "raw",
-    await window.crypto.subtle.exportKey("raw", key),
+    await crypto.subtle.exportKey("raw", key),
     key.algorithm,
     false,
     key.usages,
@@ -38,12 +45,12 @@ export const makeAESKeyNonextractable = async (key: CryptoKey) => {
 };
 
 export const wrapDataKey = async (dataKey: CryptoKey, masterKey: CryptoKey) => {
-  return encodeToBase64(await window.crypto.subtle.wrapKey("raw", dataKey, masterKey, "AES-KW"));
+  return encodeToBase64(await crypto.subtle.wrapKey("raw", dataKey, masterKey, "AES-KW"));
 };
 
 export const unwrapDataKey = async (dataKeyWrapped: string, masterKey: CryptoKey) => {
   return {
-    dataKey: await window.crypto.subtle.unwrapKey(
+    dataKey: await crypto.subtle.unwrapKey(
       "raw",
       decodeFromBase64(dataKeyWrapped),
       masterKey,
@@ -56,12 +63,12 @@ export const unwrapDataKey = async (dataKeyWrapped: string, masterKey: CryptoKey
 };
 
 export const wrapHmacSecret = async (hmacSecret: CryptoKey, masterKey: CryptoKey) => {
-  return encodeToBase64(await window.crypto.subtle.wrapKey("raw", hmacSecret, masterKey, "AES-KW"));
+  return encodeToBase64(await crypto.subtle.wrapKey("raw", hmacSecret, masterKey, "AES-KW"));
 };
 
 export const unwrapHmacSecret = async (hmacSecretWrapped: string, masterKey: CryptoKey) => {
   return {
-    hmacSecret: await window.crypto.subtle.unwrapKey(
+    hmacSecret: await crypto.subtle.unwrapKey(
       "raw",
       decodeFromBase64(hmacSecretWrapped),
       masterKey,
@@ -77,8 +84,8 @@ export const unwrapHmacSecret = async (hmacSecretWrapped: string, masterKey: Cry
 };
 
 export const encryptData = async (data: BufferSource, dataKey: CryptoKey) => {
-  const iv = window.crypto.getRandomValues(new Uint8Array(12));
-  const ciphertext = await window.crypto.subtle.encrypt(
+  const iv = crypto.getRandomValues(new Uint8Array(12));
+  const ciphertext = await crypto.subtle.encrypt(
     {
       name: "AES-GCM",
       iv,
@@ -86,14 +93,18 @@ export const encryptData = async (data: BufferSource, dataKey: CryptoKey) => {
     dataKey,
     data,
   );
-  return { ciphertext, iv: encodeToBase64(iv.buffer) };
+  return { ciphertext, iv: iv.buffer };
 };
 
-export const decryptData = async (ciphertext: BufferSource, iv: string, dataKey: CryptoKey) => {
-  return await window.crypto.subtle.decrypt(
+export const decryptData = async (
+  ciphertext: BufferSource,
+  iv: string | BufferSource,
+  dataKey: CryptoKey,
+) => {
+  return await crypto.subtle.decrypt(
     {
       name: "AES-GCM",
-      iv: decodeFromBase64(iv),
+      iv: typeof iv === "string" ? decodeFromBase64(iv) : iv,
     } satisfies AesGcmParams,
     dataKey,
     ciphertext,
@@ -102,9 +113,22 @@ export const decryptData = async (ciphertext: BufferSource, iv: string, dataKey:
 
 export const encryptString = async (plaintext: string, dataKey: CryptoKey) => {
   const { ciphertext, iv } = await encryptData(encodeString(plaintext), dataKey);
-  return { ciphertext: encodeToBase64(ciphertext), iv };
+  return { ciphertext: encodeToBase64(ciphertext), iv: encodeToBase64(iv) };
 };
 
 export const decryptString = async (ciphertext: string, iv: string, dataKey: CryptoKey) => {
   return decodeString(await decryptData(decodeFromBase64(ciphertext), iv, dataKey));
 };
+
+export const encryptChunk = async (chunk: ArrayBuffer, dataKey: CryptoKey) => {
+  const { ciphertext, iv } = await encryptData(chunk, dataKey);
+  return concatenateBuffers(iv, ciphertext).buffer;
+};
+
+export const decryptChunk = async (encryptedChunk: ArrayBuffer, dataKey: CryptoKey) => {
+  return await decryptData(
+    encryptedChunk.slice(AES_GCM_IV_SIZE),
+    encryptedChunk.slice(0, AES_GCM_IV_SIZE),
+    dataKey,
+  );
+};

src/lib/modules/crypto/rsa.ts

@@ -1,7 +1,7 @@
 import { encodeString, encodeToBase64, decodeFromBase64 } from "./util";
 
 export const generateEncryptionKeyPair = async () => {
-  const keyPair = await window.crypto.subtle.generateKey(
+  const keyPair = await crypto.subtle.generateKey(
     {
       name: "RSA-OAEP",
       modulusLength: 4096,
@@ -18,7 +18,7 @@ export const generateEncryptionKeyPair = async () => {
 };
 
 export const generateSigningKeyPair = async () => {
-  const keyPair = await window.crypto.subtle.generateKey(
+  const keyPair = await crypto.subtle.generateKey(
     {
       name: "RSA-PSS",
       modulusLength: 4096,
@@ -37,7 +37,7 @@ export const generateSigningKeyPair = async () => {
 export const exportRSAKey = async (key: CryptoKey) => {
   const format = key.type === "public" ? ("spki" as const) : ("pkcs8" as const);
   return {
-    key: await window.crypto.subtle.exportKey(format, key),
+    key: await crypto.subtle.exportKey(format, key),
     format,
   };
 };
@@ -54,14 +54,14 @@ export const importEncryptionKeyPairFromBase64 = async (
     name: "RSA-OAEP",
     hash: "SHA-256",
   };
-  const encryptKey = await window.crypto.subtle.importKey(
+  const encryptKey = await crypto.subtle.importKey(
     "spki",
     decodeFromBase64(encryptKeyBase64),
     algorithm,
     true,
     ["encrypt", "wrapKey"],
   );
-  const decryptKey = await window.crypto.subtle.importKey(
+  const decryptKey = await crypto.subtle.importKey(
     "pkcs8",
     decodeFromBase64(decryptKeyBase64),
     algorithm,
@@ -79,14 +79,14 @@ export const importSigningKeyPairFromBase64 = async (
     name: "RSA-PSS",
     hash: "SHA-256",
   };
-  const signKey = await window.crypto.subtle.importKey(
+  const signKey = await crypto.subtle.importKey(
     "pkcs8",
     decodeFromBase64(signKeyBase64),
     algorithm,
     true,
     ["sign"],
   );
-  const verifyKey = await window.crypto.subtle.importKey(
+  const verifyKey = await crypto.subtle.importKey(
     "spki",
     decodeFromBase64(verifyKeyBase64),
     algorithm,
@@ -98,17 +98,11 @@ export const importSigningKeyPairFromBase64 = async (
 
 export const makeRSAKeyNonextractable = async (key: CryptoKey) => {
   const { key: exportedKey, format } = await exportRSAKey(key);
-  return await window.crypto.subtle.importKey(
-    format,
-    exportedKey,
-    key.algorithm,
-    false,
-    key.usages,
-  );
+  return await crypto.subtle.importKey(format, exportedKey, key.algorithm, false, key.usages);
 };
 
 export const decryptChallenge = async (challenge: string, decryptKey: CryptoKey) => {
-  return await window.crypto.subtle.decrypt(
+  return await crypto.subtle.decrypt(
     {
       name: "RSA-OAEP",
     } satisfies RsaOaepParams,
@@ -119,7 +113,7 @@ export const decryptChallenge = async (challenge: string, decryptKey: CryptoKey)
 
 export const wrapMasterKey = async (masterKey: CryptoKey, encryptKey: CryptoKey) => {
   return encodeToBase64(
-    await window.crypto.subtle.wrapKey("raw", masterKey, encryptKey, {
+    await crypto.subtle.wrapKey("raw", masterKey, encryptKey, {
       name: "RSA-OAEP",
     } satisfies RsaOaepParams),
   );
@@ -131,7 +125,7 @@ export const unwrapMasterKey = async (
   extractable = false,
 ) => {
   return {
-    masterKey: await window.crypto.subtle.unwrapKey(
+    masterKey: await crypto.subtle.unwrapKey(
       "raw",
       decodeFromBase64(masterKeyWrapped),
       decryptKey,
@@ -146,7 +140,7 @@ export const unwrapMasterKey = async (
 };
 
 export const signMessageRSA = async (message: BufferSource, signKey: CryptoKey) => {
-  return await window.crypto.subtle.sign(
+  return await crypto.subtle.sign(
     {
       name: "RSA-PSS",
       saltLength: 32, // SHA-256
@@ -161,7 +155,7 @@ export const verifySignatureRSA = async (
   signature: BufferSource,
   verifyKey: CryptoKey,
 ) => {
-  return await window.crypto.subtle.verify(
+  return await crypto.subtle.verify(
     {
       name: "RSA-PSS",
       saltLength: 32, // SHA-256

src/lib/modules/crypto/sha.ts

@@ -1,10 +1,10 @@
 export const digestMessage = async (message: BufferSource) => {
-  return await window.crypto.subtle.digest("SHA-256", message);
+  return await crypto.subtle.digest("SHA-256", message);
 };
 
 export const generateHmacSecret = async () => {
   return {
-    hmacSecret: await window.crypto.subtle.generateKey(
+    hmacSecret: await crypto.subtle.generateKey(
       {
         name: "HMAC",
         hash: "SHA-256",
@@ -16,5 +16,5 @@ export const generateHmacSecret = async () => {
 };
 
 export const signMessageHmac = async (message: BufferSource, hmacSecret: CryptoKey) => {
-  return await window.crypto.subtle.sign("HMAC", hmacSecret, message);
+  return await crypto.subtle.sign("HMAC", hmacSecret, message);
 };

src/lib/modules/file/download.svelte.ts

@@ -1,6 +1,7 @@
 import axios from "axios";
 import { limitFunction } from "p-limit";
-import { decryptData } from "$lib/modules/crypto";
+import { CHUNK_SIZE, ENCRYPTION_OVERHEAD } from "$lib/constants";
+import { decryptChunk, concatenateBuffers } from "$lib/modules/crypto";
 
 export interface FileDownloadState {
   id: number;
@@ -65,13 +66,21 @@ const decryptFile = limitFunction(
   async (
     state: FileDownloadState,
     fileEncrypted: ArrayBuffer,
-    fileEncryptedIv: string,
+    encryptedChunkSize: number,
     dataKey: CryptoKey,
   ) => {
     state.status = "decrypting";
 
-    const fileBuffer = await decryptData(fileEncrypted, fileEncryptedIv, dataKey);
+    const chunks: ArrayBuffer[] = [];
+    let offset = 0;
 
+    while (offset < fileEncrypted.byteLength) {
+      const nextOffset = Math.min(offset + encryptedChunkSize, fileEncrypted.byteLength);
+      chunks.push(await decryptChunk(fileEncrypted.slice(offset, nextOffset), dataKey));
+      offset = nextOffset;
+    }
+
+    const fileBuffer = concatenateBuffers(...chunks).buffer;
     state.status = "decrypted";
     state.result = fileBuffer;
     return fileBuffer;
@@ -79,7 +88,7 @@ const decryptFile = limitFunction(
   { concurrency: 4 },
 );
 
-export const downloadFile = async (id: number, fileEncryptedIv: string, dataKey: CryptoKey) => {
+export const downloadFile = async (id: number, dataKey: CryptoKey, isLegacy: boolean) => {
   downloadingFiles.push({
     id,
     status: "download-pending",
@@ -87,7 +96,13 @@ export const downloadFile = async (id: number, fileEncryptedIv: string, dataKey:
   const state = downloadingFiles.at(-1)!;
 
   try {
-    return await decryptFile(state, await requestFileDownload(state, id), fileEncryptedIv, dataKey);
+    const fileEncrypted = await requestFileDownload(state, id);
+    return await decryptFile(
+      state,
+      fileEncrypted,
+      isLegacy ? fileEncrypted.byteLength : CHUNK_SIZE + ENCRYPTION_OVERHEAD,
+      dataKey,
+    );
   } catch (e) {
     state.status = "error";
     throw e;

src/lib/modules/file/thumbnail.ts

@@ -5,7 +5,6 @@ import { decryptData } from "$lib/modules/crypto";
 import type { SummarizedFileInfo } from "$lib/modules/filesystem";
 import { readFile, writeFile, deleteFile, deleteDirectory } from "$lib/modules/opfs";
 import { getThumbnailUrl } from "$lib/modules/thumbnail";
-import { isTRPCClientError, trpc } from "$trpc/client";
 
 const loadedThumbnails = new LRUCache<number, Writable<string>>({ max: 100 });
 const loadingThumbnails = new Map<number, Writable<string | undefined>>();
@@ -18,25 +17,18 @@ const fetchFromOpfs = async (fileId: number) => {
 };
 
 const fetchFromServer = async (fileId: number, dataKey: CryptoKey) => {
-  try {
-    const [thumbnailEncrypted, { contentIv: thumbnailEncryptedIv }] = await Promise.all([
-      fetch(`/api/file/${fileId}/thumbnail/download`),
-      trpc().file.thumbnail.query({ id: fileId }),
-    ]);
+  const res = await fetch(`/api/file/${fileId}/thumbnail/download`);
+  if (!res.ok) return null;
+
+  const thumbnailEncrypted = await res.arrayBuffer();
   const thumbnailBuffer = await decryptData(
-      await thumbnailEncrypted.arrayBuffer(),
-      thumbnailEncryptedIv,
+    thumbnailEncrypted.slice(12),
+    thumbnailEncrypted.slice(0, 12),
     dataKey,
   );
 
   void writeFile(`/thumbnail/file/${fileId}`, thumbnailBuffer);
   return getThumbnailUrl(thumbnailBuffer);
-  } catch (e) {
-    if (isTRPCClientError(e) && e.data?.code === "NOT_FOUND") {
-      return null;
-    }
-    throw e;
-  }
 };
 
 export const getFileThumbnail = (file: SummarizedFileInfo) => {

src/lib/modules/file/upload.svelte.ts

@@ -1,24 +1,23 @@
 import axios from "axios";
 import ExifReader from "exifreader";
 import { limitFunction } from "p-limit";
+import { CHUNK_SIZE } from "$lib/constants";
 import {
   encodeToBase64,
   generateDataKey,
   wrapDataKey,
   encryptData,
   encryptString,
+  encryptChunk,
   digestMessage,
   signMessageHmac,
 } from "$lib/modules/crypto";
 import { Scheduler } from "$lib/modules/scheduler";
 import { generateThumbnail } from "$lib/modules/thumbnail";
-import type {
-  FileThumbnailUploadRequest,
-  FileUploadRequest,
-  FileUploadResponse,
-} from "$lib/server/schemas";
+import type { FileThumbnailUploadRequest } from "$lib/server/schemas";
 import type { MasterKey, HmacSecret } from "$lib/stores";
 import { trpc } from "$trpc/client";
+import type { RouterInputs } from "$trpc/router.server";
 
 export interface FileUploadState {
   name: string;
@@ -110,6 +109,23 @@ const extractExifDateTime = (fileBuffer: ArrayBuffer) => {
   return new Date(utcDate - offsetMs);
 };
 
+const encryptChunks = async (fileBuffer: ArrayBuffer, dataKey: CryptoKey) => {
+  const chunksEncrypted: { chunkEncrypted: ArrayBuffer; chunkEncryptedHash: string }[] = [];
+  let offset = 0;
+
+  while (offset < fileBuffer.byteLength) {
+    const nextOffset = Math.min(offset + CHUNK_SIZE, fileBuffer.byteLength);
+    const chunkEncrypted = await encryptChunk(fileBuffer.slice(offset, nextOffset), dataKey);
+    chunksEncrypted.push({
+      chunkEncrypted: chunkEncrypted,
+      chunkEncryptedHash: encodeToBase64(await digestMessage(chunkEncrypted)),
+    });
+    offset = nextOffset;
+  }
+
+  return chunksEncrypted;
+};
+
 const encryptFile = limitFunction(
   async (state: FileUploadState, file: File, fileBuffer: ArrayBuffer, masterKey: MasterKey) => {
     state.status = "encrypting";
@@ -123,9 +139,7 @@ const encryptFile = limitFunction(
 
     const { dataKey, dataKeyVersion } = await generateDataKey();
     const dataKeyWrapped = await wrapDataKey(dataKey, masterKey.key);
-
-    const fileEncrypted = await encryptData(fileBuffer, dataKey);
-    const fileEncryptedHash = encodeToBase64(await digestMessage(fileEncrypted.ciphertext));
+    const chunksEncrypted = await encryptChunks(fileBuffer, dataKey);
 
     const nameEncrypted = await encryptString(file.name, dataKey);
     const createdAtEncrypted =
@@ -142,8 +156,7 @@ const encryptFile = limitFunction(
       dataKeyWrapped,
       dataKeyVersion,
       fileType,
-      fileEncrypted,
-      fileEncryptedHash,
+      chunksEncrypted,
       nameEncrypted,
       createdAtEncrypted,
       lastModifiedAtEncrypted,
@@ -154,30 +167,70 @@ const encryptFile = limitFunction(
 );
 
 const requestFileUpload = limitFunction(
-  async (state: FileUploadState, form: FormData, thumbnailForm: FormData | null) => {
+  async (
+    state: FileUploadState,
+    metadata: RouterInputs["file"]["startUpload"],
+    chunksEncrypted: { chunkEncrypted: ArrayBuffer; chunkEncryptedHash: string }[],
+    fileSigned: string | undefined,
+    thumbnailForm: FormData | null,
+  ) => {
     state.status = "uploading";
 
-    const res = await axios.post("/api/file/upload", form, {
-      onUploadProgress: ({ progress, rate, estimated }) => {
-        state.progress = progress;
+    const { uploadId } = await trpc().file.startUpload.mutate(metadata);
+
+    // Upload chunks with progress tracking
+    const totalBytes = chunksEncrypted.reduce((sum, c) => sum + c.chunkEncrypted.byteLength, 0);
+    let uploadedBytes = 0;
+    const startTime = Date.now();
+
+    for (let i = 0; i < chunksEncrypted.length; i++) {
+      const { chunkEncrypted, chunkEncryptedHash } = chunksEncrypted[i]!;
+
+      const response = await fetch(`/api/file/upload/${uploadId}/chunks/${i}`, {
+        method: "POST",
+        headers: {
+          "Content-Type": "application/octet-stream",
+          "Content-Digest": `sha-256=:${chunkEncryptedHash}:`,
+        },
+        body: chunkEncrypted,
+      });
+
+      if (!response.ok) {
+        throw new Error(`Chunk upload failed: ${response.status} ${response.statusText}`);
+      }
+
+      uploadedBytes += chunkEncrypted.byteLength;
+
+      // Calculate progress, rate, estimated
+      const elapsed = (Date.now() - startTime) / 1000; // seconds
+      const rate = uploadedBytes / elapsed; // bytes per second
+      const remaining = totalBytes - uploadedBytes;
+      const estimated = rate > 0 ? remaining / rate : undefined;
+
+      state.progress = uploadedBytes / totalBytes;
       state.rate = rate;
       state.estimated = estimated;
-      },
-    });
-    const { file }: FileUploadResponse = res.data;
+    }
 
+    // Complete upload
+    const { file: fileId } = await trpc().file.completeUpload.mutate({
+      uploadId,
+      contentHmac: fileSigned,
+    });
+
+    // Upload thumbnail if exists
     if (thumbnailForm) {
       try {
-        await axios.post(`/api/file/${file}/thumbnail/upload`, thumbnailForm);
+        await axios.post(`/api/file/${fileId}/thumbnail/upload`, thumbnailForm);
       } catch (e) {
-        // TODO
+        // TODO: Error handling for thumbnail upload
         console.error(e);
       }
     }
 
     state.status = "uploaded";
 
-    return { fileId: file };
+    return { fileId };
   },
   { concurrency: 1 },
 );
@@ -215,36 +268,28 @@ export const uploadFile = async (
         dataKeyWrapped,
         dataKeyVersion,
         fileType,
-        fileEncrypted,
-        fileEncryptedHash,
+        chunksEncrypted,
         nameEncrypted,
         createdAtEncrypted,
         lastModifiedAtEncrypted,
         thumbnail,
       } = await encryptFile(state, file, fileBuffer, masterKey);
 
-      const form = new FormData();
-      form.set(
-        "metadata",
-        JSON.stringify({
+      const metadata = {
+        chunks: chunksEncrypted.length,
         parent: parentId,
         mekVersion: masterKey.version,
         dek: dataKeyWrapped,
-          dekVersion: dataKeyVersion.toISOString(),
+        dekVersion: dataKeyVersion,
         hskVersion: hmacSecret.version,
-          contentHmac: fileSigned,
         contentType: fileType,
-          contentIv: fileEncrypted.iv,
         name: nameEncrypted.ciphertext,
         nameIv: nameEncrypted.iv,
         createdAt: createdAtEncrypted?.ciphertext,
         createdAtIv: createdAtEncrypted?.iv,
         lastModifiedAt: lastModifiedAtEncrypted.ciphertext,
         lastModifiedAtIv: lastModifiedAtEncrypted.iv,
-        } satisfies FileUploadRequest),
-      );
-      form.set("content", new Blob([fileEncrypted.ciphertext]));
-      form.set("checksum", fileEncryptedHash);
+      };
 
       let thumbnailForm = null;
       if (thumbnail) {
@@ -253,13 +298,19 @@ export const uploadFile = async (
           "metadata",
           JSON.stringify({
             dekVersion: dataKeyVersion.toISOString(),
-            contentIv: thumbnail.iv,
+            contentIv: encodeToBase64(thumbnail.iv),
           } satisfies FileThumbnailUploadRequest),
         );
         thumbnailForm.set("content", new Blob([thumbnail.ciphertext]));
       }
 
-      const { fileId } = await requestFileUpload(state, form, thumbnailForm);
+      const { fileId } = await requestFileUpload(
+        state,
+        metadata,
+        chunksEncrypted,
+        fileSigned,
+        thumbnailForm,
+      );
       return { fileId, fileBuffer, thumbnailBuffer: thumbnail?.plaintext };
     } catch (e) {
       state.status = "error";

src/lib/modules/filesystem/file.ts

@@ -47,10 +47,10 @@ const cache = new FilesystemCache<number, MaybeFileInfo>({
 
       return storeToIndexedDB({
         id,
+        isLegacy: file.isLegacy,
         parentId: file.parent,
         dataKey: metadata.dataKey,
         contentType: file.contentType,
-        contentIv: file.contentIv,
         name: metadata.name,
         createdAt: metadata.createdAt,
         lastModifiedAt: metadata.lastModifiedAt,
@@ -116,9 +116,9 @@ const cache = new FilesystemCache<number, MaybeFileInfo>({
         return {
           id,
           exists: true as const,
+          isLegacy: metadataRaw.isLegacy,
           parentId: metadataRaw.parent,
           contentType: metadataRaw.contentType,
-          contentIv: metadataRaw.contentIv,
           categories,
           ...metadata,
         };

src/lib/modules/filesystem/types.ts

@@ -28,10 +28,10 @@ export type SubDirectoryInfo = Omit<LocalDirectoryInfo, "subDirectories" | "file
 
 export interface FileInfo {
   id: number;
+  isLegacy?: boolean;
   parentId: DirectoryId;
   dataKey?: DataKey;
   contentType: string;
-  contentIv?: string;
   name: string;
   createdAt?: Date;
   lastModifiedAt: Date;
@@ -42,7 +42,7 @@ export type MaybeFileInfo =
   | (FileInfo & { exists: true })
   | ({ id: number; exists: false } & AllUndefined<Omit<FileInfo, "id">>);
 
-export type SummarizedFileInfo = Omit<FileInfo, "contentIv" | "categories">;
+export type SummarizedFileInfo = Omit<FileInfo, "categories">;
 export type CategoryFileInfo = SummarizedFileInfo & { isRecursive: boolean };
 
 interface LocalCategoryInfo {

src/lib/modules/http.ts

@@ -0,0 +1,14 @@
+export const parseRangeHeader = (rangeHeader: string | null) => {
+  if (!rangeHeader) return undefined;
+
+  const firstRange = rangeHeader.split(",")[0]!.trim();
+  const parts = firstRange.replace(/bytes=/, "").split("-");
+  return {
+    start: parts[0] ? parseInt(parts[0], 10) : undefined,
+    end: parts[1] ? parseInt(parts[1], 10) : undefined,
+  };
+};
+
+export const getContentRangeHeader = (range?: { start: number; end: number; total: number }) => {
+  return range && { "Content-Range": `bytes ${range.start}-${range.end}/${range.total}` };
+};

src/lib/modules/opfs.ts

@@ -1,13 +1,5 @@
-let rootHandle: FileSystemDirectoryHandle | null = null;
-
-export const prepareOpfs = async () => {
-  rootHandle = await navigator.storage.getDirectory();
-};
-
 const getFileHandle = async (path: string, create = true) => {
-  if (!rootHandle) {
-    throw new Error("OPFS not prepared");
-  } else if (path[0] !== "/") {
+  if (path[0] !== "/") {
     throw new Error("Path must be absolute");
   }
 
@@ -17,7 +9,7 @@ const getFileHandle = async (path: string, create = true) => {
   }
 
   try {
-    let directoryHandle = rootHandle;
+    let directoryHandle = await navigator.storage.getDirectory();
     for (const part of parts.slice(0, -1)) {
       if (!part) continue;
       directoryHandle = await directoryHandle.getDirectoryHandle(part, { create });
@@ -34,12 +26,15 @@ const getFileHandle = async (path: string, create = true) => {
   }
 };
 
-export const readFile = async (path: string) => {
+export const getFile = async (path: string) => {
   const { fileHandle } = await getFileHandle(path, false);
   if (!fileHandle) return null;
 
-  const file = await fileHandle.getFile();
-  return await file.arrayBuffer();
+  return await fileHandle.getFile();
+};
+
+export const readFile = async (path: string) => {
+  return (await getFile(path))?.arrayBuffer() ?? null;
 };
 
 export const writeFile = async (path: string, data: ArrayBuffer) => {
@@ -61,9 +56,7 @@ export const deleteFile = async (path: string) => {
 };
 
 const getDirectoryHandle = async (path: string) => {
-  if (!rootHandle) {
-    throw new Error("OPFS not prepared");
-  } else if (path[0] !== "/") {
+  if (path[0] !== "/") {
     throw new Error("Path must be absolute");
   }
 
@@ -73,7 +66,7 @@ const getDirectoryHandle = async (path: string) => {
   }
 
   try {
-    let directoryHandle = rootHandle;
+    let directoryHandle = await navigator.storage.getDirectory();
     let parentHandle;
     for (const part of parts.slice(1)) {
       if (!part) continue;

src/lib/server/db/file.ts

@@ -15,8 +15,6 @@ interface Directory {
   encName: Ciphertext;
 }
 
-export type NewDirectory = Omit<Directory, "id">;
-
 interface File {
   id: number;
   parentId: DirectoryId;
@@ -28,15 +26,13 @@ interface File {
   hskVersion: number | null;
   contentHmac: string | null;
   contentType: string;
-  encContentIv: string;
+  encContentIv: string | null;
   encContentHash: string;
   encName: Ciphertext;
   encCreatedAt: Ciphertext | null;
   encLastModifiedAt: Ciphertext;
 }
 
-export type NewFile = Omit<File, "id">;
-
 interface FileCategory {
   id: number;
   parentId: CategoryId;
@@ -46,7 +42,7 @@ interface FileCategory {
   encName: Ciphertext;
 }
 
-export const registerDirectory = async (params: NewDirectory) => {
+export const registerDirectory = async (params: Omit<Directory, "id">) => {
   await db.transaction().execute(async (trx) => {
     const mek = await trx
       .selectFrom("master_encryption_key")
@@ -214,38 +210,11 @@ export const unregisterDirectory = async (userId: number, directoryId: number) =
     });
 };
 
-export const registerFile = async (params: NewFile) => {
+export const registerFile = async (trx: typeof db, params: Omit<File, "id">) => {
   if ((params.hskVersion && !params.contentHmac) || (!params.hskVersion && params.contentHmac)) {
     throw new Error("Invalid arguments");
   }
 
-  return await db.transaction().execute(async (trx) => {
-    const mek = await trx
-      .selectFrom("master_encryption_key")
-      .select("version")
-      .where("user_id", "=", params.userId)
-      .where("state", "=", "active")
-      .limit(1)
-      .forUpdate()
-      .executeTakeFirst();
-    if (mek?.version !== params.mekVersion) {
-      throw new IntegrityError("Inactive MEK version");
-    }
-
-    if (params.hskVersion) {
-      const hsk = await trx
-        .selectFrom("hmac_secret_key")
-        .select("version")
-        .where("user_id", "=", params.userId)
-        .where("state", "=", "active")
-        .limit(1)
-        .forUpdate()
-        .executeTakeFirst();
-      if (hsk?.version !== params.hskVersion) {
-        throw new IntegrityError("Inactive HSK version");
-      }
-    }
-
   const { fileId } = await trx
     .insertInto("file")
     .values({
@@ -276,7 +245,6 @@ export const registerFile = async (params: NewFile) => {
     })
     .execute();
   return { id: fileId };
-  });
 };
 
 export const getAllFilesByParent = async (userId: number, parentId: DirectoryId) => {

src/lib/server/db/index.ts

@@ -5,6 +5,7 @@ export * as HskRepo from "./hsk";
 export * as MediaRepo from "./media";
 export * as MekRepo from "./mek";
 export * as SessionRepo from "./session";
+export * as UploadRepo from "./upload";
 export * as UserRepo from "./user";
 
 export * from "./error";

src/lib/server/db/migrations/1768062380-AddChunkedUpload.ts

@@ -0,0 +1,50 @@
+import { Kysely, sql } from "kysely";
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export const up = async (db: Kysely<any>) => {
+  // file.ts
+  await db.schema
+    .alterTable("file")
+    .alterColumn("encrypted_content_iv", (col) => col.dropNotNull())
+    .execute();
+
+  // upload.ts
+  await db.schema
+    .createTable("upload_session")
+    .addColumn("id", "uuid", (col) => col.primaryKey().defaultTo(sql`gen_random_uuid()`))
+    .addColumn("user_id", "integer", (col) => col.references("user.id").notNull())
+    .addColumn("total_chunks", "integer", (col) => col.notNull())
+    .addColumn("uploaded_chunks", sql`integer[]`, (col) => col.notNull().defaultTo(sql`'{}'`))
+    .addColumn("expires_at", "timestamp(3)", (col) => col.notNull())
+    .addColumn("parent_id", "integer", (col) => col.references("directory.id"))
+    .addColumn("master_encryption_key_version", "integer", (col) => col.notNull())
+    .addColumn("encrypted_data_encryption_key", "text", (col) => col.notNull())
+    .addColumn("data_encryption_key_version", "timestamp(3)", (col) => col.notNull())
+    .addColumn("hmac_secret_key_version", "integer")
+    .addColumn("content_type", "text", (col) => col.notNull())
+    .addColumn("encrypted_name", "json", (col) => col.notNull())
+    .addColumn("encrypted_created_at", "json")
+    .addColumn("encrypted_last_modified_at", "json", (col) => col.notNull())
+    .addForeignKeyConstraint(
+      "upload_session_fk01",
+      ["user_id", "master_encryption_key_version"],
+      "master_encryption_key",
+      ["user_id", "version"],
+    )
+    .addForeignKeyConstraint(
+      "upload_session_fk02",
+      ["user_id", "hmac_secret_key_version"],
+      "hmac_secret_key",
+      ["user_id", "version"],
+    )
+    .execute();
+};
+
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export const down = async (db: Kysely<any>) => {
+  await db.schema.dropTable("upload_session").execute();
+  await db.schema
+    .alterTable("file")
+    .alterColumn("encrypted_content_iv", (col) => col.setNotNull())
+    .execute();
+};

src/lib/server/db/migrations/index.ts

@@ -1,9 +1,11 @@
 import * as Initial1737357000 from "./1737357000-Initial";
 import * as AddFileCategory1737422340 from "./1737422340-AddFileCategory";
 import * as AddThumbnail1738409340 from "./1738409340-AddThumbnail";
+import * as AddChunkedUpload1768062380 from "./1768062380-AddChunkedUpload";
 
 export default {
   "1737357000-Initial": Initial1737357000,
   "1737422340-AddFileCategory": AddFileCategory1737422340,
   "1738409340-AddThumbnail": AddThumbnail1738409340,
+  "1768062380-AddChunkedUpload": AddChunkedUpload1768062380,
 };

src/lib/server/db/schema/file.ts

@@ -30,7 +30,7 @@ interface FileTable {
   hmac_secret_key_version: number | null;
   content_hmac: string | null; // Base64
   content_type: string;
-  encrypted_content_iv: string; // Base64
+  encrypted_content_iv: string | null; // Base64
   encrypted_content_hash: string; // Base64
   encrypted_name: Ciphertext;
   encrypted_created_at: Ciphertext | null;

src/lib/server/db/schema/index.ts

@@ -5,6 +5,7 @@ export * from "./hsk";
 export * from "./media";
 export * from "./mek";
 export * from "./session";
+export * from "./upload";
 export * from "./user";
 export * from "./util";
 

src/lib/server/db/schema/upload.ts

@@ -0,0 +1,26 @@
+import type { Generated } from "kysely";
+import type { Ciphertext } from "./util";
+
+interface UploadSessionTable {
+  id: Generated<string>;
+  user_id: number;
+  total_chunks: number;
+  uploaded_chunks: Generated<number[]>;
+  expires_at: Date;
+
+  parent_id: number | null;
+  master_encryption_key_version: number;
+  encrypted_data_encryption_key: string; // Base64
+  data_encryption_key_version: Date;
+  hmac_secret_key_version: number | null;
+  content_type: string;
+  encrypted_name: Ciphertext;
+  encrypted_created_at: Ciphertext | null;
+  encrypted_last_modified_at: Ciphertext;
+}
+
+declare module "./index" {
+  interface Database {
+    upload_session: UploadSessionTable;
+  }
+}

src/lib/server/db/upload.ts

@@ -0,0 +1,122 @@
+import { sql } from "kysely";
+import { IntegrityError } from "./error";
+import db from "./kysely";
+import type { Ciphertext } from "./schema";
+
+interface UploadSession {
+  id: string;
+  userId: number;
+  totalChunks: number;
+  uploadedChunks: number[];
+  expiresAt: Date;
+
+  parentId: DirectoryId;
+  mekVersion: number;
+  encDek: string;
+  dekVersion: Date;
+  hskVersion: number | null;
+  contentType: string;
+  encName: Ciphertext;
+  encCreatedAt: Ciphertext | null;
+  encLastModifiedAt: Ciphertext;
+}
+
+export const createUploadSession = async (params: Omit<UploadSession, "id" | "uploadedChunks">) => {
+  return await db.transaction().execute(async (trx) => {
+    const mek = await trx
+      .selectFrom("master_encryption_key")
+      .select("version")
+      .where("user_id", "=", params.userId)
+      .where("state", "=", "active")
+      .limit(1)
+      .forUpdate()
+      .executeTakeFirst();
+    if (mek?.version !== params.mekVersion) {
+      throw new IntegrityError("Inactive MEK version");
+    }
+
+    if (params.hskVersion) {
+      const hsk = await trx
+        .selectFrom("hmac_secret_key")
+        .select("version")
+        .where("user_id", "=", params.userId)
+        .where("state", "=", "active")
+        .limit(1)
+        .forUpdate()
+        .executeTakeFirst();
+      if (hsk?.version !== params.hskVersion) {
+        throw new IntegrityError("Inactive HSK version");
+      }
+    }
+
+    const { sessionId } = await trx
+      .insertInto("upload_session")
+      .values({
+        user_id: params.userId,
+        total_chunks: params.totalChunks,
+        expires_at: params.expiresAt,
+        parent_id: params.parentId !== "root" ? params.parentId : null,
+        master_encryption_key_version: params.mekVersion,
+        encrypted_data_encryption_key: params.encDek,
+        data_encryption_key_version: params.dekVersion,
+        hmac_secret_key_version: params.hskVersion,
+        content_type: params.contentType,
+        encrypted_name: params.encName,
+        encrypted_created_at: params.encCreatedAt,
+        encrypted_last_modified_at: params.encLastModifiedAt,
+      })
+      .returning("id as sessionId")
+      .executeTakeFirstOrThrow();
+    return { id: sessionId };
+  });
+};
+
+export const getUploadSession = async (sessionId: string, userId: number) => {
+  const session = await db
+    .selectFrom("upload_session")
+    .selectAll()
+    .where("id", "=", sessionId)
+    .where("user_id", "=", userId)
+    .where("expires_at", ">", new Date())
+    .limit(1)
+    .executeTakeFirst();
+  return session
+    ? ({
+        id: session.id,
+        userId: session.user_id,
+        totalChunks: session.total_chunks,
+        uploadedChunks: session.uploaded_chunks,
+        expiresAt: session.expires_at,
+        parentId: session.parent_id ?? "root",
+        mekVersion: session.master_encryption_key_version,
+        encDek: session.encrypted_data_encryption_key,
+        dekVersion: session.data_encryption_key_version,
+        hskVersion: session.hmac_secret_key_version,
+        contentType: session.content_type,
+        encName: session.encrypted_name,
+        encCreatedAt: session.encrypted_created_at,
+        encLastModifiedAt: session.encrypted_last_modified_at,
+      } satisfies UploadSession)
+    : null;
+};
+
+export const markChunkAsUploaded = async (sessionId: string, chunkIndex: number) => {
+  await db
+    .updateTable("upload_session")
+    .set({ uploaded_chunks: sql`array_append(uploaded_chunks, ${chunkIndex})` })
+    .where("id", "=", sessionId)
+    .execute();
+};
+
+export const deleteUploadSession = async (trx: typeof db, sessionId: string) => {
+  await trx.deleteFrom("upload_session").where("id", "=", sessionId).execute();
+};
+
+export const cleanupExpiredUploadSessions = async () => {
+  const sessions = await db
+    .deleteFrom("upload_session")
+    .where("expires_at", "<", new Date())
+    .returning("id")
+    .execute();
+  return sessions.map(({ id }) => id);
+};

src/lib/server/loadenv.ts

@@ -26,4 +26,5 @@ export default {
   },
   libraryPath: env.LIBRARY_PATH || "library",
   thumbnailsPath: env.THUMBNAILS_PATH || "thumbnails",
+  uploadsPath: env.UPLOADS_PATH || "uploads",
 };

src/lib/server/modules/filesystem.ts

@@ -1,4 +1,7 @@
 import { unlink } from "fs/promises";
+import env from "$lib/server/loadenv";
+
+export const getChunkDirectoryPath = (sessionId: string) => `${env.uploadsPath}/${sessionId}`;
 
 export const safeUnlink = async (path: string | null | undefined) => {
   if (path) {

src/lib/server/schemas/file.ts

@@ -1,36 +1,7 @@
-import mime from "mime";
 import { z } from "zod";
-import { directoryIdSchema } from "./directory";
 
 export const fileThumbnailUploadRequest = z.object({
   dekVersion: z.iso.datetime(),
   contentIv: z.base64().nonempty(),
 });
 export type FileThumbnailUploadRequest = z.input<typeof fileThumbnailUploadRequest>;
-
-export const fileUploadRequest = z.object({
-  parent: directoryIdSchema,
-  mekVersion: z.int().positive(),
-  dek: z.base64().nonempty(),
-  dekVersion: z.iso.datetime(),
-  hskVersion: z.int().positive(),
-  contentHmac: z.base64().nonempty(),
-  contentType: z
-    .string()
-    .trim()
-    .nonempty()
-    .refine((value) => mime.getExtension(value) !== null), // MIME type
-  contentIv: z.base64().nonempty(),
-  name: z.base64().nonempty(),
-  nameIv: z.base64().nonempty(),
-  createdAt: z.base64().nonempty().optional(),
-  createdAtIv: z.base64().nonempty().optional(),
-  lastModifiedAt: z.base64().nonempty(),
-  lastModifiedAtIv: z.base64().nonempty(),
-});
-export type FileUploadRequest = z.input<typeof fileUploadRequest>;
-
-export const fileUploadResponse = z.object({
-  file: z.int().positive(),
-});
-export type FileUploadResponse = z.output<typeof fileUploadResponse>;

src/lib/server/services/file.ts

@@ -6,34 +6,80 @@ import { dirname } from "path";
 import { Readable } from "stream";
 import { pipeline } from "stream/promises";
 import { v4 as uuidv4 } from "uuid";
-import { FileRepo, MediaRepo, IntegrityError } from "$lib/server/db";
+import { CHUNK_SIZE, ENCRYPTION_OVERHEAD } from "$lib/constants";
+import { FileRepo, MediaRepo, UploadRepo, IntegrityError } from "$lib/server/db";
 import env from "$lib/server/loadenv";
-import { safeUnlink } from "$lib/server/modules/filesystem";
+import { getChunkDirectoryPath, safeUnlink } from "$lib/server/modules/filesystem";
 
-export const getFileStream = async (userId: number, fileId: number) => {
+const uploadLocks = new Set<string>();
+
+const createEncContentStream = async (
+  path: string,
+  iv?: Buffer,
+  range?: { start?: number; end?: number },
+) => {
+  const { size: fileSize } = await stat(path);
+  const ivSize = iv?.byteLength ?? 0;
+  const totalSize = fileSize + ivSize;
+
+  const start = range?.start ?? 0;
+  const end = range?.end ?? totalSize - 1;
+  if (start > end || start < 0 || end >= totalSize) {
+    error(416, "Invalid range");
+  }
+
+  return {
+    encContentStream: Readable.toWeb(
+      Readable.from(
+        (async function* () {
+          if (start < ivSize) {
+            yield iv!.subarray(start, Math.min(end + 1, ivSize));
+          }
+          if (end >= ivSize) {
+            yield* createReadStream(path, {
+              start: Math.max(0, start - ivSize),
+              end: end - ivSize,
+            });
+          }
+        })(),
+      ),
+    ),
+    range: { start, end, total: totalSize },
+  };
+};
+
+export const getFileStream = async (
+  userId: number,
+  fileId: number,
+  range?: { start?: number; end?: number },
+) => {
   const file = await FileRepo.getFile(userId, fileId);
   if (!file) {
     error(404, "Invalid file id");
   }
 
-  const { size } = await stat(file.path);
-  return {
-    encContentStream: Readable.toWeb(createReadStream(file.path)),
-    encContentSize: size,
-  };
+  return createEncContentStream(
+    file.path,
+    file.encContentIv ? Buffer.from(file.encContentIv, "base64") : undefined,
+    range,
+  );
 };
 
-export const getFileThumbnailStream = async (userId: number, fileId: number) => {
+export const getFileThumbnailStream = async (
+  userId: number,
+  fileId: number,
+  range?: { start?: number; end?: number },
+) => {
   const thumbnail = await MediaRepo.getFileThumbnail(userId, fileId);
   if (!thumbnail) {
     error(404, "File or its thumbnail not found");
   }
 
-  const { size } = await stat(thumbnail.path);
-  return {
-    encContentStream: Readable.toWeb(createReadStream(thumbnail.path)),
-    encContentSize: size,
-  };
+  return createEncContentStream(
+    thumbnail.path,
+    Buffer.from(thumbnail.encContentIv, "base64"),
+    range,
+  );
 };
 
 export const uploadFileThumbnail = async (
@@ -71,56 +117,70 @@ export const uploadFileThumbnail = async (
   }
 };
 
-export const uploadFile = async (
-  params: Omit<FileRepo.NewFile, "path" | "encContentHash">,
-  encContentStream: Readable,
-  encContentHash: Promise<string>,
+export const uploadChunk = async (
+  userId: number,
+  sessionId: string,
+  chunkIndex: number,
+  encChunkStream: Readable,
+  encChunkHash: string,
 ) => {
-  const oneDayAgo = new Date(Date.now() - 24 * 60 * 60 * 1000);
-  const oneMinuteLater = new Date(Date.now() + 60 * 1000);
-  if (params.dekVersion <= oneDayAgo || params.dekVersion >= oneMinuteLater) {
-    error(400, "Invalid DEK version");
+  const lockKey = `${sessionId}/${chunkIndex}`;
+  if (uploadLocks.has(lockKey)) {
+    error(409, "Chunk already uploaded"); // TODO: Message
+  } else {
+    uploadLocks.add(lockKey);
   }
 
-  const path = `${env.libraryPath}/${params.userId}/${uuidv4()}`;
-  await mkdir(dirname(path), { recursive: true });
+  const filePath = `${getChunkDirectoryPath(sessionId)}/${chunkIndex}`;
 
   try {
+    const session = await UploadRepo.getUploadSession(sessionId, userId);
+    if (!session) {
+      error(404, "Invalid upload id");
+    } else if (chunkIndex >= session.totalChunks) {
+      error(400, "Invalid chunk index");
+    } else if (session.uploadedChunks.includes(chunkIndex)) {
+      error(409, "Chunk already uploaded");
+    }
+
+    const isLastChunk = chunkIndex === session.totalChunks - 1;
+
+    let writtenBytes = 0;
     const hashStream = createHash("sha256");
-    const [, hash] = await Promise.all([
-      pipeline(
-        encContentStream,
-        async function* (source) {
-          for await (const chunk of source) {
+    const writeStream = createWriteStream(filePath, { flags: "wx", mode: 0o600 });
+
+    for await (const chunk of encChunkStream) {
+      writtenBytes += chunk.length;
       hashStream.update(chunk);
-            yield chunk;
-          }
-        },
-        createWriteStream(path, { flags: "wx", mode: 0o600 }),
-      ),
-      encContentHash,
-    ]);
-    if (hashStream.digest("base64") !== hash) {
-      throw new Error("Invalid checksum");
+      writeStream.write(chunk);
     }
 
-    const { id: fileId } = await FileRepo.registerFile({
-      ...params,
-      path,
-      encContentHash: hash,
+    await new Promise<void>((resolve, reject) => {
+      writeStream.end((e: any) => (e ? reject(e) : resolve()));
     });
-    return { fileId };
-  } catch (e) {
-    await safeUnlink(path);
 
-    if (e instanceof IntegrityError && e.message === "Inactive MEK version") {
-      error(400, "Invalid MEK version");
+    if (hashStream.digest("base64") !== encChunkHash) {
+      throw new Error("Invalid checksum");
     } else if (
+      (!isLastChunk && writtenBytes !== CHUNK_SIZE + ENCRYPTION_OVERHEAD) ||
+      (isLastChunk &&
+        (writtenBytes <= ENCRYPTION_OVERHEAD || writtenBytes > CHUNK_SIZE + ENCRYPTION_OVERHEAD))
+    ) {
+      throw new Error("Invalid chunk size");
+    }
+
+    await UploadRepo.markChunkAsUploaded(sessionId, chunkIndex);
+  } catch (e) {
+    await safeUnlink(filePath);
+
+    if (
       e instanceof Error &&
-      (e.message === "Invalid request body" || e.message === "Invalid checksum")
+      (e.message === "Invalid checksum" || e.message === "Invalid chunk size")
     ) {
       error(400, "Invalid request body");
     }
     throw e;
+  } finally {
+    uploadLocks.delete(lockKey);
   }
 };

src/lib/serviceWorker/client.ts

@@ -0,0 +1,39 @@
+import { DECRYPTED_FILE_URL_PREFIX } from "$lib/constants";
+import type { FileMetadata, ServiceWorkerMessage, ServiceWorkerResponse } from "./types";
+
+const PREPARE_TIMEOUT_MS = 5000;
+
+const getServiceWorker = async () => {
+  const registration = await navigator.serviceWorker.ready;
+  const sw = registration.active;
+  if (!sw) {
+    throw new Error("Service worker not activated");
+  }
+  return sw;
+};
+
+export const prepareFileDecryption = async (id: number, metadata: FileMetadata) => {
+  const sw = await getServiceWorker();
+  return new Promise<void>((resolve, reject) => {
+    const timeout = setTimeout(
+      () => reject(new Error("Service worker timeout")),
+      PREPARE_TIMEOUT_MS,
+    );
+    const handler = (event: MessageEvent<ServiceWorkerResponse>) => {
+      if (event.data.type === "decryption-ready" && event.data.fileId === id) {
+        clearTimeout(timeout);
+        navigator.serviceWorker.removeEventListener("message", handler);
+        resolve();
+      }
+    };
+    navigator.serviceWorker.addEventListener("message", handler);
+
+    sw.postMessage({
+      type: "decryption-prepare",
+      fileId: id,
+      ...metadata,
+    } satisfies ServiceWorkerMessage);
+  });
+};
+
+export const getDecryptedFileUrl = (id: number) => `${DECRYPTED_FILE_URL_PREFIX}${id}`;

src/lib/serviceWorker/index.ts

@@ -0,0 +1,2 @@
+export * from "./client";
+export * from "./types";

src/lib/serviceWorker/types.ts

@@ -0,0 +1,19 @@
+export interface FileMetadata {
+  isLegacy: boolean;
+  dataKey: CryptoKey;
+  encContentSize: number;
+  contentType: string;
+}
+
+export interface DecryptionPrepareMessage extends FileMetadata {
+  type: "decryption-prepare";
+  fileId: number;
+}
+
+export interface DecryptionReadyMessage {
+  type: "decryption-ready";
+  fileId: number;
+}
+
+export type ServiceWorkerMessage = DecryptionPrepareMessage;
+export type ServiceWorkerResponse = DecryptionReadyMessage;

src/lib/services/file.ts

@@ -1,4 +1,5 @@
 import { getAllFileInfos } from "$lib/indexedDB/filesystem";
+import { encodeToBase64 } from "$lib/modules/crypto";
 import {
   getFileCache,
   storeFileCache,
@@ -11,13 +12,13 @@ import { trpc } from "$trpc/client";
 
 export const requestFileDownload = async (
   fileId: number,
-  fileEncryptedIv: string,
   dataKey: CryptoKey,
+  isLegacy: boolean,
 ) => {
   const cache = await getFileCache(fileId);
   if (cache) return cache;
 
-  const fileBuffer = await downloadFile(fileId, fileEncryptedIv, dataKey);
+  const fileBuffer = await downloadFile(fileId, dataKey, isLegacy);
   storeFileCache(fileId, fileBuffer); // Intended
   return fileBuffer;
 };
@@ -25,14 +26,14 @@ export const requestFileDownload = async (
 export const requestFileThumbnailUpload = async (
   fileId: number,
   dataKeyVersion: Date,
-  thumbnailEncrypted: { ciphertext: ArrayBuffer; iv: string },
+  thumbnailEncrypted: { ciphertext: ArrayBuffer; iv: ArrayBuffer },
 ) => {
   const form = new FormData();
   form.set(
     "metadata",
     JSON.stringify({
       dekVersion: dataKeyVersion.toISOString(),
-      contentIv: thumbnailEncrypted.iv,
+      contentIv: encodeToBase64(thumbnailEncrypted.iv),
     } satisfies FileThumbnailUploadRequest),
   );
   form.set("content", new Blob([thumbnailEncrypted.ciphertext]));

src/routes/(fullscreen)/file/[id]/+page.svelte

@@ -5,7 +5,7 @@
   import { page } from "$app/state";
   import { FullscreenDiv } from "$lib/components/atoms";
   import { Categories, IconEntryButton, TopBar } from "$lib/components/molecules";
-  import { getFileInfo, type FileInfo, type MaybeFileInfo } from "$lib/modules/filesystem";
+  import { getFileInfo, type MaybeFileInfo } from "$lib/modules/filesystem";
   import { captureVideoThumbnail } from "$lib/modules/thumbnail";
   import { getFileDownloadState } from "$lib/modules/file";
   import { masterKeyStore } from "$lib/stores";
@@ -17,6 +17,7 @@
     requestFileDownload,
     requestThumbnailUpload,
     requestFileAdditionToCategory,
+    requestVideoStream,
   } from "./service";
   import TopBarMenu from "./TopBarMenu.svelte";
 
@@ -37,6 +38,7 @@
   let viewerType: "image" | "video" | undefined = $state();
   let fileBlob: Blob | undefined = $state();
   let fileBlobUrl: string | undefined = $state();
+  let videoStreamUrl: string | undefined = $state();
   let videoElement: HTMLVideoElement | undefined = $state();
 
   const updateViewer = async (buffer: ArrayBuffer, contentType: string) => {
@@ -95,7 +97,19 @@
       untrack(() => {
         if (!downloadState && !isDownloadRequested) {
           isDownloadRequested = true;
-          requestFileDownload(data.id, info!.contentIv!, info!.dataKey!.key).then(
+
+          if (viewerType === "video" && !info!.isLegacy) {
+            requestVideoStream(data.id, info!.dataKey!.key, contentType).then((streamUrl) => {
+              if (streamUrl) {
+                videoStreamUrl = streamUrl;
+              } else {
+                requestFileDownload(data.id, info!.dataKey!.key, info!.isLegacy!).then((buffer) =>
+                  updateViewer(buffer, contentType),
+                );
+              }
+            });
+          } else {
+            requestFileDownload(data.id, info!.dataKey!.key, info!.isLegacy!).then(
               async (buffer) => {
                 const blob = await updateViewer(buffer, contentType);
                 if (!viewerType) {
@@ -104,13 +118,16 @@
               },
             );
           }
+        }
       });
     }
   });
 
   $effect(() => {
     if (info?.exists && downloadState?.status === "decrypted") {
-      untrack(() => !isDownloadRequested && updateViewer(downloadState.result!, info!.contentIv!));
+      untrack(
+        () => !isDownloadRequested && updateViewer(downloadState.result!, info!.contentType!),
+      );
     }
   });
 
@@ -137,6 +154,7 @@
         ? info?.parentId
         : undefined}
       {fileBlob}
+      downloadUrl={videoStreamUrl}
       filename={info?.name}
     />
   </div>
@@ -159,9 +177,10 @@
             {@render viewerLoading("이미지를 불러오고 있어요.")}
           {/if}
         {:else if viewerType === "video"}
-          {#if fileBlobUrl}
+          {#if videoStreamUrl || fileBlobUrl}
             <div class="flex flex-col space-y-2">
-              <video bind:this={videoElement} src={fileBlobUrl} controls muted></video>
+              <video bind:this={videoElement} src={videoStreamUrl ?? fileBlobUrl} controls muted
+              ></video>
               <IconEntryButton
                 icon={IconCamera}
                 onclick={() => updateThumbnail(info?.dataKey?.key!, info?.dataKey?.version!)}

src/routes/(fullscreen)/file/[id]/TopBarMenu.svelte

@@ -10,17 +10,29 @@
 
   interface Props {
     directoryId?: "root" | number;
+    downloadUrl?: string;
     fileBlob?: Blob;
     filename?: string;
     isOpen: boolean;
   }
 
-  let { directoryId, fileBlob, filename, isOpen = $bindable() }: Props = $props();
+  let { directoryId, downloadUrl, fileBlob, filename, isOpen = $bindable() }: Props = $props();
+
+  const handleDownload = () => {
+    if (fileBlob && filename) {
+      FileSaver.saveAs(fileBlob, filename);
+    } else if (downloadUrl && filename) {
+      // Use streaming download via Content-Disposition header
+      const url = new URL(downloadUrl, window.location.origin);
+      url.searchParams.set("download", filename);
+      window.open(url.toString(), "_blank");
+    }
+  };
 </script>
 
 <svelte:window onclick={() => (isOpen = false)} />
 
-{#if isOpen && (directoryId || fileBlob)}
+{#if isOpen && (directoryId || downloadUrl || fileBlob)}
   <div
     class="absolute right-2 top-full z-20 space-y-1 rounded-lg bg-white px-1 py-2 shadow-2xl"
     transition:fly={{ y: -8, duration: 200 }}
@@ -49,10 +61,8 @@
           ),
         )}
       {/if}
-      {#if fileBlob}
-        {@render menuButton(IconCloudDownload, "다운로드", () => {
-          FileSaver.saveAs(fileBlob, filename);
-        })}
+      {#if fileBlob || downloadUrl}
+        {@render menuButton(IconCloudDownload, "다운로드", handleDownload)}
       {/if}
     </div>
   </div>

src/routes/(fullscreen)/file/[id]/service.ts

@@ -1,11 +1,32 @@
 import { encryptData } from "$lib/modules/crypto";
 import { storeFileThumbnailCache } from "$lib/modules/file";
+import { prepareFileDecryption, getDecryptedFileUrl } from "$lib/serviceWorker";
 import { requestFileThumbnailUpload } from "$lib/services/file";
 import { trpc } from "$trpc/client";
 
 export { requestCategoryCreation, requestFileRemovalFromCategory } from "$lib/services/category";
 export { requestFileDownload } from "$lib/services/file";
 
+export const requestVideoStream = async (
+  fileId: number,
+  dataKey: CryptoKey,
+  contentType: string,
+) => {
+  const res = await fetch(`/api/file/${fileId}/download`, { method: "HEAD" });
+  if (!res.ok) return null;
+
+  const encContentSize = parseInt(res.headers.get("Content-Length") ?? "0", 10);
+  if (encContentSize <= 0) return null;
+
+  try {
+    await prepareFileDecryption(fileId, { isLegacy: false, dataKey, encContentSize, contentType });
+    return getDecryptedFileUrl(fileId);
+  } catch {
+    // TODO: Error Handling
+    return null;
+  }
+};
+
 export const requestThumbnailUpload = async (
   fileId: number,
   thumbnail: Blob,

src/routes/(fullscreen)/settings/thumbnail/service.ts

@@ -50,7 +50,7 @@ const requestThumbnailUpload = limitFunction(
   async (
     fileId: number,
     dataKeyVersion: Date,
-    thumbnail: { plaintext: ArrayBuffer; ciphertext: ArrayBuffer; iv: string },
+    thumbnail: { plaintext: ArrayBuffer; ciphertext: ArrayBuffer; iv: ArrayBuffer },
   ) => {
     statuses.set(fileId, "uploading");
 
@@ -77,7 +77,7 @@ export const requestThumbnailGeneration = async (fileInfo: FileInfo) => {
     await scheduler.schedule(
       async () => {
         statuses.set(fileInfo.id, "generation-pending");
-        file = await requestFileDownload(fileInfo.id, fileInfo.contentIv!, fileInfo.dataKey?.key!);
+        file = await requestFileDownload(fileInfo.id, fileInfo.dataKey?.key!, fileInfo.isLegacy!);
         return file.byteLength;
       },
       async () => {

src/routes/api/file/[id]/download/+server.ts

@@ -1,10 +1,15 @@
 import { error } from "@sveltejs/kit";
 import { z } from "zod";
 import { authorize } from "$lib/server/modules/auth";
+import { parseRangeHeader, getContentRangeHeader } from "$lib/modules/http";
 import { getFileStream } from "$lib/server/services/file";
 import type { RequestHandler } from "./$types";
 
-export const GET: RequestHandler = async ({ locals, params }) => {
+const downloadHandler = async (
+  locals: App.Locals,
+  params: Record<string, string>,
+  request: Request,
+) => {
   const { userId } = await authorize(locals, "activeClient");
 
   const zodRes = z
@@ -15,11 +20,29 @@ export const GET: RequestHandler = async ({ locals, params }) => {
   if (!zodRes.success) error(400, "Invalid path parameters");
   const { id } = zodRes.data;
 
-  const { encContentStream, encContentSize } = await getFileStream(userId, id);
-  return new Response(encContentStream as ReadableStream, {
+  const { encContentStream, range } = await getFileStream(
+    userId,
+    id,
+    parseRangeHeader(request.headers.get("Range")),
+  );
+  return {
+    stream: encContentStream,
     headers: {
+      "Accept-Ranges": "bytes",
+      "Content-Length": (range.end - range.start + 1).toString(),
       "Content-Type": "application/octet-stream",
-      "Content-Length": encContentSize.toString(),
+      ...getContentRangeHeader(range),
     },
-  });
+    isRangeRequest: !!range,
+  };
+};
+
+export const GET: RequestHandler = async ({ locals, params, request }) => {
+  const { stream, headers, isRangeRequest } = await downloadHandler(locals, params, request);
+  return new Response(stream as ReadableStream, { status: isRangeRequest ? 206 : 200, headers });
+};
+
+export const HEAD: RequestHandler = async ({ locals, params, request }) => {
+  const { headers, isRangeRequest } = await downloadHandler(locals, params, request);
+  return new Response(null, { status: isRangeRequest ? 206 : 200, headers });
 };

src/routes/api/file/[id]/thumbnail/download/+server.ts

@@ -1,10 +1,15 @@
 import { error } from "@sveltejs/kit";
 import { z } from "zod";
 import { authorize } from "$lib/server/modules/auth";
+import { parseRangeHeader, getContentRangeHeader } from "$lib/modules/http";
 import { getFileThumbnailStream } from "$lib/server/services/file";
 import type { RequestHandler } from "./$types";
 
-export const GET: RequestHandler = async ({ locals, params }) => {
+const downloadHandler = async (
+  locals: App.Locals,
+  params: Record<string, string>,
+  request: Request,
+) => {
   const { userId } = await authorize(locals, "activeClient");
 
   const zodRes = z
@@ -15,11 +20,29 @@ export const GET: RequestHandler = async ({ locals, params }) => {
   if (!zodRes.success) error(400, "Invalid path parameters");
   const { id } = zodRes.data;
 
-  const { encContentStream, encContentSize } = await getFileThumbnailStream(userId, id);
-  return new Response(encContentStream as ReadableStream, {
+  const { encContentStream, range } = await getFileThumbnailStream(
+    userId,
+    id,
+    parseRangeHeader(request.headers.get("Range")),
+  );
+  return {
+    stream: encContentStream,
     headers: {
+      "Accept-Ranges": "bytes",
+      "Content-Length": (range.end - range.start + 1).toString(),
       "Content-Type": "application/octet-stream",
-      "Content-Length": encContentSize.toString(),
+      ...getContentRangeHeader(range),
     },
-  });
+    isRangeRequest: !!range,
+  };
+};
+
+export const GET: RequestHandler = async ({ locals, params, request }) => {
+  const { stream, headers, isRangeRequest } = await downloadHandler(locals, params, request);
+  return new Response(stream as ReadableStream, { status: isRangeRequest ? 206 : 200, headers });
+};
+
+export const HEAD: RequestHandler = async ({ locals, params, request }) => {
+  const { headers, isRangeRequest } = await downloadHandler(locals, params, request);
+  return new Response(null, { status: isRangeRequest ? 206 : 200, headers });
 };

src/routes/api/file/upload/+server.ts

@@ -1,108 +0,0 @@
-import Busboy from "@fastify/busboy";
-import { error, json } from "@sveltejs/kit";
-import { Readable, Writable } from "stream";
-import { authorize } from "$lib/server/modules/auth";
-import {
-  fileUploadRequest,
-  fileUploadResponse,
-  type FileUploadResponse,
-} from "$lib/server/schemas";
-import { uploadFile } from "$lib/server/services/file";
-import type { RequestHandler } from "./$types";
-
-type FileMetadata = Parameters<typeof uploadFile>[0];
-
-const parseFileMetadata = (userId: number, json: string) => {
-  const zodRes = fileUploadRequest.safeParse(JSON.parse(json));
-  if (!zodRes.success) error(400, "Invalid request body");
-  const {
-    parent,
-    mekVersion,
-    dek,
-    dekVersion,
-    hskVersion,
-    contentHmac,
-    contentType,
-    contentIv,
-    name,
-    nameIv,
-    createdAt,
-    createdAtIv,
-    lastModifiedAt,
-    lastModifiedAtIv,
-  } = zodRes.data;
-  if ((createdAt && !createdAtIv) || (!createdAt && createdAtIv))
-    error(400, "Invalid request body");
-
-  return {
-    userId,
-    parentId: parent,
-    mekVersion,
-    encDek: dek,
-    dekVersion: new Date(dekVersion),
-    hskVersion,
-    contentHmac,
-    contentType,
-    encContentIv: contentIv,
-    encName: { ciphertext: name, iv: nameIv },
-    encCreatedAt: createdAt && createdAtIv ? { ciphertext: createdAt, iv: createdAtIv } : null,
-    encLastModifiedAt: { ciphertext: lastModifiedAt, iv: lastModifiedAtIv },
-  } satisfies FileMetadata;
-};
-
-export const POST: RequestHandler = async ({ locals, request }) => {
-  const { userId } = await authorize(locals, "activeClient");
-
-  const contentType = request.headers.get("Content-Type");
-  if (!contentType?.startsWith("multipart/form-data") || !request.body) {
-    error(400, "Invalid request body");
-  }
-
-  return new Promise<Response>((resolve, reject) => {
-    const bb = Busboy({ headers: { "content-type": contentType } });
-    const handler =
-      <T extends unknown[]>(f: (...args: T) => Promise<void>) =>
-      (...args: T) => {
-        f(...args).catch(reject);
-      };
-
-    let metadata: FileMetadata | null = null;
-    let content: Readable | null = null;
-    const checksum = new Promise<string>((resolveChecksum, rejectChecksum) => {
-      bb.on(
-        "field",
-        handler(async (fieldname, val) => {
-          if (fieldname === "metadata") {
-            // Ignore subsequent metadata fields
-            if (!metadata) {
-              metadata = parseFileMetadata(userId, val);
-            }
-          } else if (fieldname === "checksum") {
-            // Ignore subsequent checksum fields
-            resolveChecksum(val);
-          } else {
-            error(400, "Invalid request body");
-          }
-        }),
-      );
-      bb.on(
-        "file",
-        handler(async (fieldname, file) => {
-          if (fieldname !== "content") error(400, "Invalid request body");
-          if (!metadata || content) error(400, "Invalid request body");
-          content = file;
-
-          const { fileId } = await uploadFile(metadata, content, checksum);
-          resolve(json(fileUploadResponse.parse({ file: fileId } satisfies FileUploadResponse)));
-        }),
-      );
-      bb.on("finish", () => rejectChecksum(new Error("Invalid request body")));
-      bb.on("error", (e) => {
-        content?.emit("error", e) ?? reject(e);
-        rejectChecksum(e);
-      });
-    });
-
-    request.body!.pipeTo(Writable.toWeb(bb)).catch(() => {}); // busboy will handle the error
-  });
-};

src/routes/api/file/upload/[id]/chunks/[index]/+server.ts

@@ -0,0 +1,43 @@
+import { error, text } from "@sveltejs/kit";
+import { Readable } from "stream";
+import { z } from "zod";
+import { authorize } from "$lib/server/modules/auth";
+import { uploadChunk } from "$lib/server/services/file";
+import type { RequestHandler } from "./$types";
+
+export const POST: RequestHandler = async ({ locals, params, request }) => {
+  const { userId } = await authorize(locals, "activeClient");
+
+  const zodRes = z
+    .object({
+      id: z.uuidv4(),
+      index: z.coerce.number().int().nonnegative(),
+    })
+    .safeParse(params);
+  if (!zodRes.success) error(400, "Invalid path parameters");
+  const { id: uploadId, index: chunkIndex } = zodRes.data;
+
+  // Parse Content-Digest header (RFC 9530)
+  // Expected format: sha-256=:base64hash:
+  const contentDigest = request.headers.get("Content-Digest");
+  if (!contentDigest) error(400, "Missing Content-Digest header");
+
+  const digestMatch = contentDigest.match(/^sha-256=:([A-Za-z0-9+/=]+):$/);
+  if (!digestMatch || !digestMatch[1])
+    error(400, "Invalid Content-Digest format, must be sha-256=:base64:");
+  const encChunkHash = digestMatch[1];
+
+  const contentType = request.headers.get("Content-Type");
+  if (contentType !== "application/octet-stream" || !request.body) {
+    error(400, "Invalid request body");
+  }
+
+  // Convert web ReadableStream to Node Readable
+  const nodeReadable = Readable.fromWeb(
+    request.body as unknown as Parameters<typeof Readable.fromWeb>[0],
+  );
+
+  await uploadChunk(userId, uploadId, chunkIndex, nodeReadable, encChunkHash);
+
+  return text("Chunk uploaded", { headers: { "Content-Type": "text/plain" } });
+};

src/service-worker/handlers/decryptFile.ts

@@ -0,0 +1,153 @@
+import { DECRYPTED_FILE_URL_PREFIX, CHUNK_SIZE, ENCRYPTED_CHUNK_SIZE } from "../modules/constants";
+import { decryptChunk, getEncryptedRange, getDecryptedSize } from "../modules/crypto";
+import { parseRangeHeader, getContentRangeHeader } from "../modules/http";
+import { getFile } from "../modules/opfs";
+import { fileMetadataStore } from "../stores";
+import type { FileMetadata } from "../types";
+
+const createResponse = (
+  stream: ReadableStream<Uint8Array>,
+  isRangeRequest: boolean,
+  range: { start: number; end: number; total: number },
+  contentType?: string,
+  downloadFilename?: string,
+) => {
+  const headers: Record<string, string> = {
+    "Accept-Ranges": "bytes",
+    "Content-Length": String(range.end - range.start + 1),
+    "Content-Type": contentType ?? "application/octet-stream",
+    ...(isRangeRequest ? getContentRangeHeader(range) : {}),
+  };
+
+  if (downloadFilename) {
+    headers["Content-Disposition"] =
+      `attachment; filename*=UTF-8''${encodeURIComponent(downloadFilename)}`;
+  }
+
+  return new Response(stream, {
+    status: isRangeRequest ? 206 : 200,
+    headers,
+  });
+};
+
+const streamFromOpfs = async (
+  file: File,
+  metadata?: FileMetadata,
+  range?: { start?: number; end?: number },
+  downloadFilename?: string,
+) => {
+  const start = range?.start ?? 0;
+  const end = range?.end ?? file.size - 1;
+  if (start > end || start < 0 || end >= file.size) {
+    return new Response("Invalid range", { status: 416 });
+  }
+
+  return createResponse(
+    file.slice(start, end + 1).stream(),
+    !!range,
+    { start, end, total: file.size },
+    metadata?.contentType,
+    downloadFilename,
+  );
+};
+
+const streamFromServer = async (
+  id: number,
+  metadata: FileMetadata,
+  range?: { start?: number; end?: number },
+  downloadFilename?: string,
+) => {
+  const totalSize = getDecryptedSize(metadata.encContentSize, metadata.isLegacy);
+  const start = range?.start ?? 0;
+  const end =
+    range?.end ??
+    (range && !metadata.isLegacy ? Math.min(start + CHUNK_SIZE, totalSize) : totalSize) - 1;
+  if (start > end || start < 0 || end >= totalSize) {
+    return new Response("Invalid range", { status: 416 });
+  }
+
+  const encryptedRange = getEncryptedRange(start, end, metadata.encContentSize, metadata.isLegacy);
+  const apiResponse = await fetch(`/api/file/${id}/download`, {
+    headers: { Range: `bytes=${encryptedRange.start}-${encryptedRange.end}` },
+  });
+  if (apiResponse.status !== 206 || !apiResponse.body) {
+    return new Response("Failed to fetch encrypted file", { status: 502 });
+  }
+
+  if (metadata.isLegacy) {
+    const fileEncrypted = await apiResponse.arrayBuffer();
+    const decrypted = await decryptChunk(fileEncrypted, metadata.dataKey);
+    return createResponse(
+      new ReadableStream<Uint8Array>({
+        start(controller) {
+          controller.enqueue(new Uint8Array(decrypted.slice(start, end + 1)));
+          controller.close();
+        },
+      }),
+      !!range,
+      { start, end, total: totalSize },
+      metadata.contentType,
+    );
+  }
+
+  const totalChunks = encryptedRange.lastChunkIndex - encryptedRange.firstChunkIndex + 1;
+  let currentChunkIndex = 0;
+  let buffer = new Uint8Array(0);
+
+  const decryptingStream = new TransformStream<Uint8Array, Uint8Array>({
+    async transform(chunk, controller) {
+      const newBuffer = new Uint8Array(buffer.length + chunk.length);
+      newBuffer.set(buffer);
+      newBuffer.set(chunk, buffer.length);
+      buffer = newBuffer;
+
+      while (buffer.length >= ENCRYPTED_CHUNK_SIZE && currentChunkIndex < totalChunks - 1) {
+        const encryptedChunk = buffer.slice(0, ENCRYPTED_CHUNK_SIZE);
+        buffer = buffer.slice(ENCRYPTED_CHUNK_SIZE);
+
+        const decrypted = await decryptChunk(encryptedChunk.buffer, metadata.dataKey);
+        const sliceStart = currentChunkIndex === 0 ? start % CHUNK_SIZE : 0;
+        controller.enqueue(new Uint8Array(decrypted.slice(sliceStart)));
+        currentChunkIndex++;
+      }
+    },
+    async flush(controller) {
+      if (buffer.length > 0) {
+        const decrypted = await decryptChunk(buffer.buffer, metadata.dataKey);
+        const sliceStart = currentChunkIndex === 0 ? start % CHUNK_SIZE : 0;
+        const sliceEnd = (end % CHUNK_SIZE) + 1;
+        controller.enqueue(new Uint8Array(decrypted.slice(sliceStart, sliceEnd)));
+      }
+    },
+  });
+
+  return createResponse(
+    apiResponse.body.pipeThrough(decryptingStream),
+    !!range,
+    { start, end, total: totalSize },
+    metadata.contentType,
+    downloadFilename,
+  );
+};
+
+const decryptFileHandler = async (request: Request) => {
+  const url = new URL(request.url);
+  const fileId = parseInt(url.pathname.slice(DECRYPTED_FILE_URL_PREFIX.length), 10);
+  if (isNaN(fileId)) {
+    throw new Response("Invalid file id", { status: 400 });
+  }
+
+  const downloadFilename = url.searchParams.get("download") ?? undefined;
+  const metadata = fileMetadataStore.get(fileId);
+  const range = parseRangeHeader(request.headers.get("Range"));
+  const cache = await getFile(`/cache/${fileId}`);
+  if (cache) {
+    return streamFromOpfs(cache, metadata, range, downloadFilename);
+  } else if (metadata) {
+    return streamFromServer(fileId, metadata, range, downloadFilename);
+  } else {
+    return new Response("Decryption not prepared", { status: 400 });
+  }
+};
+
+export default decryptFileHandler;

src/service-worker/handlers/index.ts

@@ -0,0 +1 @@
+export { default as decryptFile } from "./decryptFile";

src/service-worker/index.ts

@@ -0,0 +1,43 @@
+/// <reference no-default-lib="true"/>
+/// <reference lib="esnext" />
+/// <reference lib="webworker" />
+/// <reference types="@sveltejs/kit" />
+
+import { DECRYPTED_FILE_URL_PREFIX } from "./modules/constants";
+import { decryptFile } from "./handlers";
+import { fileMetadataStore } from "./stores";
+import type { ServiceWorkerMessage, ServiceWorkerResponse } from "./types";
+
+const self = globalThis.self as unknown as ServiceWorkerGlobalScope;
+
+self.addEventListener("message", (event) => {
+  const message: ServiceWorkerMessage = event.data;
+  switch (message.type) {
+    case "decryption-prepare":
+      fileMetadataStore.set(message.fileId, message);
+      event.source?.postMessage({
+        type: "decryption-ready",
+        fileId: message.fileId,
+      } satisfies ServiceWorkerResponse);
+      break;
+    default: {
+      const exhaustive: never = message.type;
+      return exhaustive;
+    }
+  }
+});
+
+self.addEventListener("fetch", (event) => {
+  const url = new URL(event.request.url);
+  if (url.pathname.startsWith(DECRYPTED_FILE_URL_PREFIX)) {
+    event.respondWith(decryptFile(event.request));
+  }
+});
+
+self.addEventListener("install", () => {
+  self.skipWaiting();
+});
+
+self.addEventListener("activate", (event) => {
+  event.waitUntil(self.clients.claim());
+});

src/service-worker/modules/constants.ts

@@ -0,0 +1 @@
+export * from "../../lib/constants";

src/service-worker/modules/crypto.ts

@@ -0,0 +1,40 @@
+import { ENCRYPTION_OVERHEAD, CHUNK_SIZE, ENCRYPTED_CHUNK_SIZE } from "./constants";
+
+export * from "../../lib/modules/crypto";
+
+export const getEncryptedRange = (
+  start: number,
+  end: number,
+  totalEncryptedSize: number,
+  isLegacy: boolean,
+) => {
+  if (isLegacy) {
+    return {
+      firstChunkIndex: 0,
+      lastChunkIndex: 0,
+      start: 0,
+      end: totalEncryptedSize - 1,
+    };
+  }
+
+  const firstChunkIndex = Math.floor(start / CHUNK_SIZE);
+  const lastChunkIndex = Math.floor(end / CHUNK_SIZE);
+  return {
+    firstChunkIndex,
+    lastChunkIndex,
+    start: firstChunkIndex * ENCRYPTED_CHUNK_SIZE,
+    end: Math.min((lastChunkIndex + 1) * ENCRYPTED_CHUNK_SIZE - 1, totalEncryptedSize - 1),
+  };
+};
+
+export const getDecryptedSize = (encryptedSize: number, isLegacy: boolean) => {
+  if (isLegacy) {
+    return encryptedSize - ENCRYPTION_OVERHEAD;
+  }
+
+  const fullChunks = Math.floor(encryptedSize / ENCRYPTED_CHUNK_SIZE);
+  const lastChunkEncSize = encryptedSize % ENCRYPTED_CHUNK_SIZE;
+  return (
+    fullChunks * CHUNK_SIZE + (lastChunkEncSize > 0 ? lastChunkEncSize - ENCRYPTION_OVERHEAD : 0)
+  );
+};

src/service-worker/modules/http.ts

@@ -0,0 +1 @@
+export * from "../../lib/modules/http";

src/service-worker/modules/opfs.ts

@@ -0,0 +1 @@
+export * from "../../lib/modules/opfs";

src/service-worker/stores.ts

@@ -0,0 +1,3 @@
+import type { FileMetadata } from "./types";
+
+export const fileMetadataStore = new Map<number, FileMetadata>();

src/service-worker/types.ts

@@ -0,0 +1 @@
+export * from "../lib/serviceWorker/types";

src/trpc/routers/file.ts

@@ -1,9 +1,20 @@
 import { TRPCError } from "@trpc/server";
+import { createHash } from "crypto";
+import { createReadStream, createWriteStream } from "fs";
+import { mkdir, rm } from "fs/promises";
+import mime from "mime";
+import { dirname } from "path";
+import { v4 as uuidv4 } from "uuid";
 import { z } from "zod";
-import { FileRepo, MediaRepo, IntegrityError } from "$lib/server/db";
-import { safeUnlink } from "$lib/server/modules/filesystem";
+import { FileRepo, MediaRepo, UploadRepo, IntegrityError } from "$lib/server/db";
+import db from "$lib/server/db/kysely";
+import env from "$lib/server/loadenv";
+import { getChunkDirectoryPath, safeUnlink } from "$lib/server/modules/filesystem";
+import { directoryIdSchema } from "$lib/server/schemas";
 import { router, roleProcedure } from "../init.server";
 
+const uploadLocks = new Set<string>();
+
 const fileRouter = router({
   get: roleProcedure["activeClient"]
     .input(
@@ -19,12 +30,12 @@ const fileRouter = router({
 
       const categories = await FileRepo.getAllFileCategories(input.id);
       return {
+        isLegacy: !!file.encContentIv,
         parent: file.parentId,
         mekVersion: file.mekVersion,
         dek: file.encDek,
         dekVersion: file.dekVersion,
         contentType: file.contentType,
-        contentIv: file.encContentIv,
         name: file.encName.ciphertext,
         nameIv: file.encName.iv,
         createdAt: file.encCreatedAt?.ciphertext,
@@ -53,12 +64,12 @@ const fileRouter = router({
       const files = await FileRepo.getFilesWithCategories(ctx.session.userId, input.ids);
       return files.map((file) => ({
         id: file.id,
+        isLegacy: !!file.encContentIv,
         parent: file.parentId,
         mekVersion: file.mekVersion,
         dek: file.encDek,
         dekVersion: file.dekVersion,
         contentType: file.contentType,
-        contentIv: file.encContentIv,
         name: file.encName.ciphertext,
         nameIv: file.encName.iv,
         createdAt: file.encCreatedAt?.ciphertext,
@@ -158,7 +169,138 @@ const fileRouter = router({
         throw new TRPCError({ code: "NOT_FOUND", message: "File or its thumbnail not found" });
       }
 
-      return { updatedAt: thumbnail.updatedAt, contentIv: thumbnail.encContentIv };
+      return { updatedAt: thumbnail.updatedAt };
+    }),
+
+  startUpload: roleProcedure["activeClient"]
+    .input(
+      z.object({
+        chunks: z.int().positive(),
+        parent: directoryIdSchema,
+        mekVersion: z.int().positive(),
+        dek: z.base64().nonempty(),
+        dekVersion: z.date(),
+        hskVersion: z.int().positive().optional(),
+        contentType: z
+          .string()
+          .trim()
+          .nonempty()
+          .refine((value) => mime.getExtension(value) !== null),
+        name: z.base64().nonempty(),
+        nameIv: z.base64().nonempty(),
+        createdAt: z.base64().nonempty().optional(),
+        createdAtIv: z.base64().nonempty().optional(),
+        lastModifiedAt: z.base64().nonempty(),
+        lastModifiedAtIv: z.base64().nonempty(),
+      }),
+    )
+    .mutation(async ({ ctx, input }) => {
+      const oneMinuteAgo = new Date(Date.now() - 60 * 1000);
+      const oneMinuteLater = new Date(Date.now() + 60 * 1000);
+      if (input.dekVersion <= oneMinuteAgo || input.dekVersion >= oneMinuteLater) {
+        throw new TRPCError({ code: "BAD_REQUEST", message: "Invalid DEK version" });
+      }
+
+      try {
+        const { id: sessionId } = await UploadRepo.createUploadSession({
+          userId: ctx.session.userId,
+          totalChunks: input.chunks,
+          expiresAt: new Date(Date.now() + 24 * 60 * 60 * 1000), // 24 hours
+          parentId: input.parent,
+          mekVersion: input.mekVersion,
+          encDek: input.dek,
+          dekVersion: input.dekVersion,
+          hskVersion: input.hskVersion ?? null,
+          contentType: input.contentType,
+          encName: { ciphertext: input.name, iv: input.nameIv },
+          encCreatedAt:
+            input.createdAt && input.createdAtIv
+              ? { ciphertext: input.createdAt, iv: input.createdAtIv }
+              : null,
+          encLastModifiedAt: { ciphertext: input.lastModifiedAt, iv: input.lastModifiedAtIv },
+        });
+        await mkdir(getChunkDirectoryPath(sessionId), { recursive: true });
+        return { uploadId: sessionId };
+      } catch (e) {
+        if (e instanceof IntegrityError) {
+          if (e.message === "Inactive MEK version") {
+            throw new TRPCError({ code: "BAD_REQUEST", message: "Invalid MEK version" });
+          } else if (e.message === "Inactive HSK version") {
+            throw new TRPCError({ code: "BAD_REQUEST", message: "Invalid HSK version" });
+          }
+        }
+        throw e;
+      }
+    }),
+
+  completeUpload: roleProcedure["activeClient"]
+    .input(
+      z.object({
+        uploadId: z.uuidv4(),
+        contentHmac: z.base64().nonempty().optional(),
+      }),
+    )
+    .mutation(async ({ ctx, input }) => {
+      const { uploadId } = input;
+      if (uploadLocks.has(uploadId)) {
+        throw new TRPCError({ code: "CONFLICT", message: "Upload already in progress" }); // TODO: Message
+      } else {
+        uploadLocks.add(uploadId);
+      }
+
+      const filePath = `${env.libraryPath}/${ctx.session.userId}/${uuidv4()}`;
+      await mkdir(dirname(filePath), { recursive: true });
+
+      try {
+        const session = await UploadRepo.getUploadSession(uploadId, ctx.session.userId);
+        if (!session) {
+          throw new TRPCError({ code: "NOT_FOUND", message: "Invalid upload id" });
+        } else if (
+          (session.hskVersion && !input.contentHmac) ||
+          (!session.hskVersion && input.contentHmac)
+        ) {
+          throw new TRPCError({ code: "BAD_REQUEST", message: "Invalid content hmac" }); // TODO: message
+        } else if (session.uploadedChunks.length < session.totalChunks) {
+          throw new TRPCError({ code: "BAD_REQUEST", message: "Upload not complete" }); // TODO: Message
+        }
+
+        const chunkDirectoryPath = getChunkDirectoryPath(uploadId);
+        const hashStream = createHash("sha256");
+        const writeStream = createWriteStream(filePath, { flags: "wx", mode: 0o600 });
+
+        for (let i = 0; i < session.totalChunks; i++) {
+          for await (const chunk of createReadStream(`${chunkDirectoryPath}/${i}`)) {
+            hashStream.update(chunk);
+            writeStream.write(chunk);
+          }
+        }
+
+        await new Promise<void>((resolve, reject) => {
+          writeStream.end((e: any) => (e ? reject(e) : resolve()));
+        });
+
+        const hash = hashStream.digest("base64");
+        const fileId = await db.transaction().execute(async (trx) => {
+          const { id: fileId } = await FileRepo.registerFile(trx, {
+            ...session,
+            userId: ctx.session.userId,
+            path: filePath,
+            contentHmac: input.contentHmac ?? null,
+            encContentHash: hash,
+            encContentIv: null,
+          });
+          await UploadRepo.deleteUploadSession(trx, uploadId);
+          return fileId;
+        });
+
+        await rm(chunkDirectoryPath, { recursive: true }).catch((e) => console.error(e));
+        return { file: fileId };
+      } catch (e) {
+        await safeUnlink(filePath);
+        throw e;
+      } finally {
+        uploadLocks.delete(uploadId);
+      }
     }),
 });