fix: add support for integrity option to Fetch (nodejs#1596)

* Test case for fetch() integrity option.

* Implement matchRequestIntegrity

* Add test to cover encoded body

* Speed up integrity test completion

* Fix trailing spaces

lib/fetch/util.js

@@ -5,6 +5,7 @@ const { performance } = require('perf_hooks')
 const { isBlobLike, toUSVString, ReadableStreamFrom } = require('../core/util')
 const assert = require('assert')
 const { isUint8Array } = require('util/types')
+const { createHash } = require('crypto')
 
 let File
 
@@ -341,7 +342,8 @@ function determineRequestsReferrer (request) {
 }
 
 function matchRequestIntegrity (request, bytes) {
-  return false
+  const [algo, expectedHashValue] = request.integrity.split('-', 2)
+  return createHash(algo).update(bytes).digest('hex') === expectedHashValue
 }
 
 // https://w3c.github.io/webappsec-upgrade-insecure-requests/#upgrade-request

test/fetch/client-fetch.js

@@ -536,28 +536,3 @@ test('Receiving non-Latin1 headers', async (t) => {
   t.same(lengths, [30, 34, 94, 104, 90])
   t.end()
 })
-
-// https://github.com/nodejs/undici/issues/1594
-// TODO(@KhafraDev): this test fails because of an integrity-mismatch check
-// that hasn't been implemented when this comment was written. Enable this
-// check once a resource's integrity is checked.
-// test('with RequestInit.integrity set', async (t) => {
-//   const body = 'Hello world'
-//   const hash = require('crypto').createHash('sha256').update(body).digest('hex')
-//
-//   const server = createServer((req, res) => {
-//     res.write(body)
-//     res.end()
-//   }).listen(0)
-//
-//   t.teardown(server.close.bind(server))
-//   await once(server, 'listening')
-//
-//   const response = await fetch(`http://localhost:${server.address().port}`, {
-//     integrity: `sha256-${hash}`
-//   })
-//
-//   const ab = await response.arrayBuffer()
-//
-//   t.same(new Uint8Array(ab), new TextEncoder().encode(body))
-// })

test/fetch/integrity.js

@@ -0,0 +1,74 @@
+'use strict'
+
+const { test } = require('tap')
+const { createServer } = require('http')
+const { createHash } = require('crypto')
+const { gzipSync } = require('zlib')
+const { fetch, setGlobalDispatcher, Agent } = require('../..')
+
+setGlobalDispatcher(new Agent({
+  keepAliveTimeout: 1,
+  keepAliveMaxTimeout: 1
+}))
+
+test('request with correct integrity checksum', (t) => {
+  const body = 'Hello world!'
+  const hash = createHash('sha256').update(body).digest('hex')
+
+  const server = createServer((req, res) => {
+    res.end(body)
+  })
+
+  t.teardown(server.close.bind(server))
+
+  server.listen(0, async () => {
+    const response = await fetch(`http://localhost:${server.address().port}`, {
+      integrity: `sha256-${hash}`
+    })
+    t.strictSame(body, await response.text())
+    t.end()
+  })
+})
+
+test('request with wrong integrity checksum', (t) => {
+  const body = 'Hello world!'
+  const hash = 'c0535e4be2b79ffd93291305436bf889314e4a3faec05ecffcbb7df31ad9e51b'
+
+  const server = createServer((req, res) => {
+    res.end(body)
+  })
+
+  t.teardown(server.close.bind(server))
+
+  server.listen(0, () => {
+    fetch(`http://localhost:${server.address().port}`, {
+      integrity: `sha256-${hash}`
+    }).then(response => {
+      t.fail('fetch did not fail')
+    }).catch((err) => {
+      t.equal(err.cause.message, 'integrity mismatch')
+    }).finally(() => {
+      t.end()
+    })
+  })
+})
+
+test('request with integrity checksum on encoded body', (t) => {
+  const body = 'Hello world!'
+  const hash = createHash('sha256').update(body).digest('hex')
+
+  const server = createServer((req, res) => {
+    res.setHeader('content-encoding', 'gzip')
+    res.end(gzipSync(body))
+  })
+
+  t.teardown(server.close.bind(server))
+
+  server.listen(0, async () => {
+    const response = await fetch(`http://localhost:${server.address().port}`, {
+      integrity: `sha256-${hash}`
+    })
+    t.strictSame(body, await response.text())
+    t.end()
+  })
+})