Adding upstream version 5.28.2+dfsg1+~cs23.11.12.3.upstream/5.28.2+dfsg1+_cs23.11.12.3upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

4 files changed, 1036 insertions, 0 deletions

diff --git a/lib/cache/cache.js b/lib/cache/cache.js
new file mode 100644
index 0000000..9b31108
--- /dev/null
+++ b/lib/cache/cache.js
@@ -0,0 +1,838 @@
+'use strict'
+
+const { kConstruct } = require('./symbols')
+const { urlEquals, fieldValues: getFieldValues } = require('./util')
+const { kEnumerableProperty, isDisturbed } = require('../core/util')
+const { kHeadersList } = require('../core/symbols')
+const { webidl } = require('../fetch/webidl')
+const { Response, cloneResponse } = require('../fetch/response')
+const { Request } = require('../fetch/request')
+const { kState, kHeaders, kGuard, kRealm } = require('../fetch/symbols')
+const { fetching } = require('../fetch/index')
+const { urlIsHttpHttpsScheme, createDeferredPromise, readAllBytes } = require('../fetch/util')
+const assert = require('assert')
+const { getGlobalDispatcher } = require('../global')
+
+/**
+ * @see https://w3c.github.io/ServiceWorker/#dfn-cache-batch-operation
+ * @typedef {Object} CacheBatchOperation
+ * @property {'delete' | 'put'} type
+ * @property {any} request
+ * @property {any} response
+ * @property {import('../../types/cache').CacheQueryOptions} options
+ */
+
+/**
+ * @see https://w3c.github.io/ServiceWorker/#dfn-request-response-list
+ * @typedef {[any, any][]} requestResponseList
+ */
+
+class Cache {
+  /**
+   * @see https://w3c.github.io/ServiceWorker/#dfn-relevant-request-response-list
+   * @type {requestResponseList}
+   */
+  #relevantRequestResponseList
+
+  constructor () {
+    if (arguments[0] !== kConstruct) {
+      webidl.illegalConstructor()
+    }
+
+    this.#relevantRequestResponseList = arguments[1]
+  }
+
+  async match (request, options = {}) {
+    webidl.brandCheck(this, Cache)
+    webidl.argumentLengthCheck(arguments, 1, { header: 'Cache.match' })
+
+    request = webidl.converters.RequestInfo(request)
+    options = webidl.converters.CacheQueryOptions(options)
+
+    const p = await this.matchAll(request, options)
+
+    if (p.length === 0) {
+      return
+    }
+
+    return p[0]
+  }
+
+  async matchAll (request = undefined, options = {}) {
+    webidl.brandCheck(this, Cache)
+
+    if (request !== undefined) request = webidl.converters.RequestInfo(request)
+    options = webidl.converters.CacheQueryOptions(options)
+
+    // 1.
+    let r = null
+
+    // 2.
+    if (request !== undefined) {
+      if (request instanceof Request) {
+        // 2.1.1
+        r = request[kState]
+
+        // 2.1.2
+        if (r.method !== 'GET' && !options.ignoreMethod) {
+          return []
+        }
+      } else if (typeof request === 'string') {
+        // 2.2.1
+        r = new Request(request)[kState]
+      }
+    }
+
+    // 5.
+    // 5.1
+    const responses = []
+
+    // 5.2
+    if (request === undefined) {
+      // 5.2.1
+      for (const requestResponse of this.#relevantRequestResponseList) {
+        responses.push(requestResponse[1])
+      }
+    } else { // 5.3
+      // 5.3.1
+      const requestResponses = this.#queryCache(r, options)
+
+      // 5.3.2
+      for (const requestResponse of requestResponses) {
+        responses.push(requestResponse[1])
+      }
+    }
+
+    // 5.4
+    // We don't implement CORs so we don't need to loop over the responses, yay!
+
+    // 5.5.1
+    const responseList = []
+
+    // 5.5.2
+    for (const response of responses) {
+      // 5.5.2.1
+      const responseObject = new Response(response.body?.source ?? null)
+      const body = responseObject[kState].body
+      responseObject[kState] = response
+      responseObject[kState].body = body
+      responseObject[kHeaders][kHeadersList] = response.headersList
+      responseObject[kHeaders][kGuard] = 'immutable'
+
+      responseList.push(responseObject)
+    }
+
+    // 6.
+    return Object.freeze(responseList)
+  }
+
+  async add (request) {
+    webidl.brandCheck(this, Cache)
+    webidl.argumentLengthCheck(arguments, 1, { header: 'Cache.add' })
+
+    request = webidl.converters.RequestInfo(request)
+
+    // 1.
+    const requests = [request]
+
+    // 2.
+    const responseArrayPromise = this.addAll(requests)
+
+    // 3.
+    return await responseArrayPromise
+  }
+
+  async addAll (requests) {
+    webidl.brandCheck(this, Cache)
+    webidl.argumentLengthCheck(arguments, 1, { header: 'Cache.addAll' })
+
+    requests = webidl.converters['sequence<RequestInfo>'](requests)
+
+    // 1.
+    const responsePromises = []
+
+    // 2.
+    const requestList = []
+
+    // 3.
+    for (const request of requests) {
+      if (typeof request === 'string') {
+        continue
+      }
+
+      // 3.1
+      const r = request[kState]
+
+      // 3.2
+      if (!urlIsHttpHttpsScheme(r.url) || r.method !== 'GET') {
+        throw webidl.errors.exception({
+          header: 'Cache.addAll',
+          message: 'Expected http/s scheme when method is not GET.'
+        })
+      }
+    }
+
+    // 4.
+    /** @type {ReturnType<typeof fetching>[]} */
+    const fetchControllers = []
+
+    // 5.
+    for (const request of requests) {
+      // 5.1
+      const r = new Request(request)[kState]
+
+      // 5.2
+      if (!urlIsHttpHttpsScheme(r.url)) {
+        throw webidl.errors.exception({
+          header: 'Cache.addAll',
+          message: 'Expected http/s scheme.'
+        })
+      }
+
+      // 5.4
+      r.initiator = 'fetch'
+      r.destination = 'subresource'
+
+      // 5.5
+      requestList.push(r)
+
+      // 5.6
+      const responsePromise = createDeferredPromise()
+
+      // 5.7
+      fetchControllers.push(fetching({
+        request: r,
+        dispatcher: getGlobalDispatcher(),
+        processResponse (response) {
+          // 1.
+          if (response.type === 'error' || response.status === 206 || response.status < 200 || response.status > 299) {
+            responsePromise.reject(webidl.errors.exception({
+              header: 'Cache.addAll',
+              message: 'Received an invalid status code or the request failed.'
+            }))
+          } else if (response.headersList.contains('vary')) { // 2.
+            // 2.1
+            const fieldValues = getFieldValues(response.headersList.get('vary'))
+
+            // 2.2
+            for (const fieldValue of fieldValues) {
+              // 2.2.1
+              if (fieldValue === '*') {
+                responsePromise.reject(webidl.errors.exception({
+                  header: 'Cache.addAll',
+                  message: 'invalid vary field value'
+                }))
+
+                for (const controller of fetchControllers) {
+                  controller.abort()
+                }
+
+                return
+              }
+            }
+          }
+        },
+        processResponseEndOfBody (response) {
+          // 1.
+          if (response.aborted) {
+            responsePromise.reject(new DOMException('aborted', 'AbortError'))
+            return
+          }
+
+          // 2.
+          responsePromise.resolve(response)
+        }
+      }))
+
+      // 5.8
+      responsePromises.push(responsePromise.promise)
+    }
+
+    // 6.
+    const p = Promise.all(responsePromises)
+
+    // 7.
+    const responses = await p
+
+    // 7.1
+    const operations = []
+
+    // 7.2
+    let index = 0
+
+    // 7.3
+    for (const response of responses) {
+      // 7.3.1
+      /** @type {CacheBatchOperation} */
+      const operation = {
+        type: 'put', // 7.3.2
+        request: requestList[index], // 7.3.3
+        response // 7.3.4
+      }
+
+      operations.push(operation) // 7.3.5
+
+      index++ // 7.3.6
+    }
+
+    // 7.5
+    const cacheJobPromise = createDeferredPromise()
+
+    // 7.6.1
+    let errorData = null
+
+    // 7.6.2
+    try {
+      this.#batchCacheOperations(operations)
+    } catch (e) {
+      errorData = e
+    }
+
+    // 7.6.3
+    queueMicrotask(() => {
+      // 7.6.3.1
+      if (errorData === null) {
+        cacheJobPromise.resolve(undefined)
+      } else {
+        // 7.6.3.2
+        cacheJobPromise.reject(errorData)
+      }
+    })
+
+    // 7.7
+    return cacheJobPromise.promise
+  }
+
+  async put (request, response) {
+    webidl.brandCheck(this, Cache)
+    webidl.argumentLengthCheck(arguments, 2, { header: 'Cache.put' })
+
+    request = webidl.converters.RequestInfo(request)
+    response = webidl.converters.Response(response)
+
+    // 1.
+    let innerRequest = null
+
+    // 2.
+    if (request instanceof Request) {
+      innerRequest = request[kState]
+    } else { // 3.
+      innerRequest = new Request(request)[kState]
+    }
+
+    // 4.
+    if (!urlIsHttpHttpsScheme(innerRequest.url) || innerRequest.method !== 'GET') {
+      throw webidl.errors.exception({
+        header: 'Cache.put',
+        message: 'Expected an http/s scheme when method is not GET'
+      })
+    }
+
+    // 5.
+    const innerResponse = response[kState]
+
+    // 6.
+    if (innerResponse.status === 206) {
+      throw webidl.errors.exception({
+        header: 'Cache.put',
+        message: 'Got 206 status'
+      })
+    }
+
+    // 7.
+    if (innerResponse.headersList.contains('vary')) {
+      // 7.1.
+      const fieldValues = getFieldValues(innerResponse.headersList.get('vary'))
+
+      // 7.2.
+      for (const fieldValue of fieldValues) {
+        // 7.2.1
+        if (fieldValue === '*') {
+          throw webidl.errors.exception({
+            header: 'Cache.put',
+            message: 'Got * vary field value'
+          })
+        }
+      }
+    }
+
+    // 8.
+    if (innerResponse.body && (isDisturbed(innerResponse.body.stream) || innerResponse.body.stream.locked)) {
+      throw webidl.errors.exception({
+        header: 'Cache.put',
+        message: 'Response body is locked or disturbed'
+      })
+    }
+
+    // 9.
+    const clonedResponse = cloneResponse(innerResponse)
+
+    // 10.
+    const bodyReadPromise = createDeferredPromise()
+
+    // 11.
+    if (innerResponse.body != null) {
+      // 11.1
+      const stream = innerResponse.body.stream
+
+      // 11.2
+      const reader = stream.getReader()
+
+      // 11.3
+      readAllBytes(reader).then(bodyReadPromise.resolve, bodyReadPromise.reject)
+    } else {
+      bodyReadPromise.resolve(undefined)
+    }
+
+    // 12.
+    /** @type {CacheBatchOperation[]} */
+    const operations = []
+
+    // 13.
+    /** @type {CacheBatchOperation} */
+    const operation = {
+      type: 'put', // 14.
+      request: innerRequest, // 15.
+      response: clonedResponse // 16.
+    }
+
+    // 17.
+    operations.push(operation)
+
+    // 19.
+    const bytes = await bodyReadPromise.promise
+
+    if (clonedResponse.body != null) {
+      clonedResponse.body.source = bytes
+    }
+
+    // 19.1
+    const cacheJobPromise = createDeferredPromise()
+
+    // 19.2.1
+    let errorData = null
+
+    // 19.2.2
+    try {
+      this.#batchCacheOperations(operations)
+    } catch (e) {
+      errorData = e
+    }
+
+    // 19.2.3
+    queueMicrotask(() => {
+      // 19.2.3.1
+      if (errorData === null) {
+        cacheJobPromise.resolve()
+      } else { // 19.2.3.2
+        cacheJobPromise.reject(errorData)
+      }
+    })
+
+    return cacheJobPromise.promise
+  }
+
+  async delete (request, options = {}) {
+    webidl.brandCheck(this, Cache)
+    webidl.argumentLengthCheck(arguments, 1, { header: 'Cache.delete' })
+
+    request = webidl.converters.RequestInfo(request)
+    options = webidl.converters.CacheQueryOptions(options)
+
+    /**
+     * @type {Request}
+     */
+    let r = null
+
+    if (request instanceof Request) {
+      r = request[kState]
+
+      if (r.method !== 'GET' && !options.ignoreMethod) {
+        return false
+      }
+    } else {
+      assert(typeof request === 'string')
+
+      r = new Request(request)[kState]
+    }
+
+    /** @type {CacheBatchOperation[]} */
+    const operations = []
+
+    /** @type {CacheBatchOperation} */
+    const operation = {
+      type: 'delete',
+      request: r,
+      options
+    }
+
+    operations.push(operation)
+
+    const cacheJobPromise = createDeferredPromise()
+
+    let errorData = null
+    let requestResponses
+
+    try {
+      requestResponses = this.#batchCacheOperations(operations)
+    } catch (e) {
+      errorData = e
+    }
+
+    queueMicrotask(() => {
+      if (errorData === null) {
+        cacheJobPromise.resolve(!!requestResponses?.length)
+      } else {
+        cacheJobPromise.reject(errorData)
+      }
+    })
+
+    return cacheJobPromise.promise
+  }
+
+  /**
+   * @see https://w3c.github.io/ServiceWorker/#dom-cache-keys
+   * @param {any} request
+   * @param {import('../../types/cache').CacheQueryOptions} options
+   * @returns {readonly Request[]}
+   */
+  async keys (request = undefined, options = {}) {
+    webidl.brandCheck(this, Cache)
+
+    if (request !== undefined) request = webidl.converters.RequestInfo(request)
+    options = webidl.converters.CacheQueryOptions(options)
+
+    // 1.
+    let r = null
+
+    // 2.
+    if (request !== undefined) {
+      // 2.1
+      if (request instanceof Request) {
+        // 2.1.1
+        r = request[kState]
+
+        // 2.1.2
+        if (r.method !== 'GET' && !options.ignoreMethod) {
+          return []
+        }
+      } else if (typeof request === 'string') { // 2.2
+        r = new Request(request)[kState]
+      }
+    }
+
+    // 4.
+    const promise = createDeferredPromise()
+
+    // 5.
+    // 5.1
+    const requests = []
+
+    // 5.2
+    if (request === undefined) {
+      // 5.2.1
+      for (const requestResponse of this.#relevantRequestResponseList) {
+        // 5.2.1.1
+        requests.push(requestResponse[0])
+      }
+    } else { // 5.3
+      // 5.3.1
+      const requestResponses = this.#queryCache(r, options)
+
+      // 5.3.2
+      for (const requestResponse of requestResponses) {
+        // 5.3.2.1
+        requests.push(requestResponse[0])
+      }
+    }
+
+    // 5.4
+    queueMicrotask(() => {
+      // 5.4.1
+      const requestList = []
+
+      // 5.4.2
+      for (const request of requests) {
+        const requestObject = new Request('https://a')
+        requestObject[kState] = request
+        requestObject[kHeaders][kHeadersList] = request.headersList
+        requestObject[kHeaders][kGuard] = 'immutable'
+        requestObject[kRealm] = request.client
+
+        // 5.4.2.1
+        requestList.push(requestObject)
+      }
+
+      // 5.4.3
+      promise.resolve(Object.freeze(requestList))
+    })
+
+    return promise.promise
+  }
+
+  /**
+   * @see https://w3c.github.io/ServiceWorker/#batch-cache-operations-algorithm
+   * @param {CacheBatchOperation[]} operations
+   * @returns {requestResponseList}
+   */
+  #batchCacheOperations (operations) {
+    // 1.
+    const cache = this.#relevantRequestResponseList
+
+    // 2.
+    const backupCache = [...cache]
+
+    // 3.
+    const addedItems = []
+
+    // 4.1
+    const resultList = []
+
+    try {
+      // 4.2
+      for (const operation of operations) {
+        // 4.2.1
+        if (operation.type !== 'delete' && operation.type !== 'put') {
+          throw webidl.errors.exception({
+            header: 'Cache.#batchCacheOperations',
+            message: 'operation type does not match "delete" or "put"'
+          })
+        }
+
+        // 4.2.2
+        if (operation.type === 'delete' && operation.response != null) {
+          throw webidl.errors.exception({
+            header: 'Cache.#batchCacheOperations',
+            message: 'delete operation should not have an associated response'
+          })
+        }
+
+        // 4.2.3
+        if (this.#queryCache(operation.request, operation.options, addedItems).length) {
+          throw new DOMException('???', 'InvalidStateError')
+        }
+
+        // 4.2.4
+        let requestResponses
+
+        // 4.2.5
+        if (operation.type === 'delete') {
+          // 4.2.5.1
+          requestResponses = this.#queryCache(operation.request, operation.options)
+
+          // TODO: the spec is wrong, this is needed to pass WPTs
+          if (requestResponses.length === 0) {
+            return []
+          }
+
+          // 4.2.5.2
+          for (const requestResponse of requestResponses) {
+            const idx = cache.indexOf(requestResponse)
+            assert(idx !== -1)
+
+            // 4.2.5.2.1
+            cache.splice(idx, 1)
+          }
+        } else if (operation.type === 'put') { // 4.2.6
+          // 4.2.6.1
+          if (operation.response == null) {
+            throw webidl.errors.exception({
+              header: 'Cache.#batchCacheOperations',
+              message: 'put operation should have an associated response'
+            })
+          }
+
+          // 4.2.6.2
+          const r = operation.request
+
+          // 4.2.6.3
+          if (!urlIsHttpHttpsScheme(r.url)) {
+            throw webidl.errors.exception({
+              header: 'Cache.#batchCacheOperations',
+              message: 'expected http or https scheme'
+            })
+          }
+
+          // 4.2.6.4
+          if (r.method !== 'GET') {
+            throw webidl.errors.exception({
+              header: 'Cache.#batchCacheOperations',
+              message: 'not get method'
+            })
+          }
+
+          // 4.2.6.5
+          if (operation.options != null) {
+            throw webidl.errors.exception({
+              header: 'Cache.#batchCacheOperations',
+              message: 'options must not be defined'
+            })
+          }
+
+          // 4.2.6.6
+          requestResponses = this.#queryCache(operation.request)
+
+          // 4.2.6.7
+          for (const requestResponse of requestResponses) {
+            const idx = cache.indexOf(requestResponse)
+            assert(idx !== -1)
+
+            // 4.2.6.7.1
+            cache.splice(idx, 1)
+          }
+
+          // 4.2.6.8
+          cache.push([operation.request, operation.response])
+
+          // 4.2.6.10
+          addedItems.push([operation.request, operation.response])
+        }
+
+        // 4.2.7
+        resultList.push([operation.request, operation.response])
+      }
+
+      // 4.3
+      return resultList
+    } catch (e) { // 5.
+      // 5.1
+      this.#relevantRequestResponseList.length = 0
+
+      // 5.2
+      this.#relevantRequestResponseList = backupCache
+
+      // 5.3
+      throw e
+    }
+  }
+
+  /**
+   * @see https://w3c.github.io/ServiceWorker/#query-cache
+   * @param {any} requestQuery
+   * @param {import('../../types/cache').CacheQueryOptions} options
+   * @param {requestResponseList} targetStorage
+   * @returns {requestResponseList}
+   */
+  #queryCache (requestQuery, options, targetStorage) {
+    /** @type {requestResponseList} */
+    const resultList = []
+
+    const storage = targetStorage ?? this.#relevantRequestResponseList
+
+    for (const requestResponse of storage) {
+      const [cachedRequest, cachedResponse] = requestResponse
+      if (this.#requestMatchesCachedItem(requestQuery, cachedRequest, cachedResponse, options)) {
+        resultList.push(requestResponse)
+      }
+    }
+
+    return resultList
+  }
+
+  /**
+   * @see https://w3c.github.io/ServiceWorker/#request-matches-cached-item-algorithm
+   * @param {any} requestQuery
+   * @param {any} request
+   * @param {any | null} response
+   * @param {import('../../types/cache').CacheQueryOptions | undefined} options
+   * @returns {boolean}
+   */
+  #requestMatchesCachedItem (requestQuery, request, response = null, options) {
+    // if (options?.ignoreMethod === false && request.method === 'GET') {
+    //   return false
+    // }
+
+    const queryURL = new URL(requestQuery.url)
+
+    const cachedURL = new URL(request.url)
+
+    if (options?.ignoreSearch) {
+      cachedURL.search = ''
+
+      queryURL.search = ''
+    }
+
+    if (!urlEquals(queryURL, cachedURL, true)) {
+      return false
+    }
+
+    if (
+      response == null ||
+      options?.ignoreVary ||
+      !response.headersList.contains('vary')
+    ) {
+      return true
+    }
+
+    const fieldValues = getFieldValues(response.headersList.get('vary'))
+
+    for (const fieldValue of fieldValues) {
+      if (fieldValue === '*') {
+        return false
+      }
+
+      const requestValue = request.headersList.get(fieldValue)
+      const queryValue = requestQuery.headersList.get(fieldValue)
+
+      // If one has the header and the other doesn't, or one has
+      // a different value than the other, return false
+      if (requestValue !== queryValue) {
+        return false
+      }
+    }
+
+    return true
+  }
+}
+
+Object.defineProperties(Cache.prototype, {
+  [Symbol.toStringTag]: {
+    value: 'Cache',
+    configurable: true
+  },
+  match: kEnumerableProperty,
+  matchAll: kEnumerableProperty,
+  add: kEnumerableProperty,
+  addAll: kEnumerableProperty,
+  put: kEnumerableProperty,
+  delete: kEnumerableProperty,
+  keys: kEnumerableProperty
+})
+
+const cacheQueryOptionConverters = [
+  {
+    key: 'ignoreSearch',
+    converter: webidl.converters.boolean,
+    defaultValue: false
+  },
+  {
+    key: 'ignoreMethod',
+    converter: webidl.converters.boolean,
+    defaultValue: false
+  },
+  {
+    key: 'ignoreVary',
+    converter: webidl.converters.boolean,
+    defaultValue: false
+  }
+]
+
+webidl.converters.CacheQueryOptions = webidl.dictionaryConverter(cacheQueryOptionConverters)
+
+webidl.converters.MultiCacheQueryOptions = webidl.dictionaryConverter([
+  ...cacheQueryOptionConverters,
+  {
+    key: 'cacheName',
+    converter: webidl.converters.DOMString
+  }
+])
+
+webidl.converters.Response = webidl.interfaceConverter(Response)
+
+webidl.converters['sequence<RequestInfo>'] = webidl.sequenceConverter(
+  webidl.converters.RequestInfo
+)
+
+module.exports = {
+  Cache
+}
diff --git a/lib/cache/cachestorage.js b/lib/cache/cachestorage.js
new file mode 100644
index 0000000..7e7f0cf
--- /dev/null
+++ b/lib/cache/cachestorage.js
@@ -0,0 +1,144 @@
+'use strict'
+
+const { kConstruct } = require('./symbols')
+const { Cache } = require('./cache')
+const { webidl } = require('../fetch/webidl')
+const { kEnumerableProperty } = require('../core/util')
+
+class CacheStorage {
+  /**
+   * @see https://w3c.github.io/ServiceWorker/#dfn-relevant-name-to-cache-map
+   * @type {Map<string, import('./cache').requestResponseList}
+   */
+  #caches = new Map()
+
+  constructor () {
+    if (arguments[0] !== kConstruct) {
+      webidl.illegalConstructor()
+    }
+  }
+
+  async match (request, options = {}) {
+    webidl.brandCheck(this, CacheStorage)
+    webidl.argumentLengthCheck(arguments, 1, { header: 'CacheStorage.match' })
+
+    request = webidl.converters.RequestInfo(request)
+    options = webidl.converters.MultiCacheQueryOptions(options)
+
+    // 1.
+    if (options.cacheName != null) {
+      // 1.1.1.1
+      if (this.#caches.has(options.cacheName)) {
+        // 1.1.1.1.1
+        const cacheList = this.#caches.get(options.cacheName)
+        const cache = new Cache(kConstruct, cacheList)
+
+        return await cache.match(request, options)
+      }
+    } else { // 2.
+      // 2.2
+      for (const cacheList of this.#caches.values()) {
+        const cache = new Cache(kConstruct, cacheList)
+
+        // 2.2.1.2
+        const response = await cache.match(request, options)
+
+        if (response !== undefined) {
+          return response
+        }
+      }
+    }
+  }
+
+  /**
+   * @see https://w3c.github.io/ServiceWorker/#cache-storage-has
+   * @param {string} cacheName
+   * @returns {Promise<boolean>}
+   */
+  async has (cacheName) {
+    webidl.brandCheck(this, CacheStorage)
+    webidl.argumentLengthCheck(arguments, 1, { header: 'CacheStorage.has' })
+
+    cacheName = webidl.converters.DOMString(cacheName)
+
+    // 2.1.1
+    // 2.2
+    return this.#caches.has(cacheName)
+  }
+
+  /**
+   * @see https://w3c.github.io/ServiceWorker/#dom-cachestorage-open
+   * @param {string} cacheName
+   * @returns {Promise<Cache>}
+   */
+  async open (cacheName) {
+    webidl.brandCheck(this, CacheStorage)
+    webidl.argumentLengthCheck(arguments, 1, { header: 'CacheStorage.open' })
+
+    cacheName = webidl.converters.DOMString(cacheName)
+
+    // 2.1
+    if (this.#caches.has(cacheName)) {
+      // await caches.open('v1') !== await caches.open('v1')
+
+      // 2.1.1
+      const cache = this.#caches.get(cacheName)
+
+      // 2.1.1.1
+      return new Cache(kConstruct, cache)
+    }
+
+    // 2.2
+    const cache = []
+
+    // 2.3
+    this.#caches.set(cacheName, cache)
+
+    // 2.4
+    return new Cache(kConstruct, cache)
+  }
+
+  /**
+   * @see https://w3c.github.io/ServiceWorker/#cache-storage-delete
+   * @param {string} cacheName
+   * @returns {Promise<boolean>}
+   */
+  async delete (cacheName) {
+    webidl.brandCheck(this, CacheStorage)
+    webidl.argumentLengthCheck(arguments, 1, { header: 'CacheStorage.delete' })
+
+    cacheName = webidl.converters.DOMString(cacheName)
+
+    return this.#caches.delete(cacheName)
+  }
+
+  /**
+   * @see https://w3c.github.io/ServiceWorker/#cache-storage-keys
+   * @returns {string[]}
+   */
+  async keys () {
+    webidl.brandCheck(this, CacheStorage)
+
+    // 2.1
+    const keys = this.#caches.keys()
+
+    // 2.2
+    return [...keys]
+  }
+}
+
+Object.defineProperties(CacheStorage.prototype, {
+  [Symbol.toStringTag]: {
+    value: 'CacheStorage',
+    configurable: true
+  },
+  match: kEnumerableProperty,
+  has: kEnumerableProperty,
+  open: kEnumerableProperty,
+  delete: kEnumerableProperty,
+  keys: kEnumerableProperty
+})
+
+module.exports = {
+  CacheStorage
+}
diff --git a/lib/cache/symbols.js b/lib/cache/symbols.js
new file mode 100644
index 0000000..40448d6
--- /dev/null
+++ b/lib/cache/symbols.js
@@ -0,0 +1,5 @@
+'use strict'
+
+module.exports = {
+  kConstruct: require('../core/symbols').kConstruct
+}
diff --git a/lib/cache/util.js b/lib/cache/util.js
new file mode 100644
index 0000000..44d52b7
--- /dev/null
+++ b/lib/cache/util.js
@@ -0,0 +1,49 @@
+'use strict'
+
+const assert = require('assert')
+const { URLSerializer } = require('../fetch/dataURL')
+const { isValidHeaderName } = require('../fetch/util')
+
+/**
+ * @see https://url.spec.whatwg.org/#concept-url-equals
+ * @param {URL} A
+ * @param {URL} B
+ * @param {boolean | undefined} excludeFragment
+ * @returns {boolean}
+ */
+function urlEquals (A, B, excludeFragment = false) {
+  const serializedA = URLSerializer(A, excludeFragment)
+
+  const serializedB = URLSerializer(B, excludeFragment)
+
+  return serializedA === serializedB
+}
+
+/**
+ * @see https://github.com/chromium/chromium/blob/694d20d134cb553d8d89e5500b9148012b1ba299/content/browser/cache_storage/cache_storage_cache.cc#L260-L262
+ * @param {string} header
+ */
+function fieldValues (header) {
+  assert(header !== null)
+
+  const values = []
+
+  for (let value of header.split(',')) {
+    value = value.trim()
+
+    if (!value.length) {
+      continue
+    } else if (!isValidHeaderName(value)) {
+      continue
+    }
+
+    values.push(value)
+  }
+
+  return values
+}
+
+module.exports = {
+  urlEquals,
+  fieldValues
+}