feat: add support for signed redirects (#5414)

eduardoboucas · web-flow · commit 733c47e22268 · 2023-01-20T14:21:44.000Z
diff --git a/src/utils/proxy.mjs b/src/utils/proxy.mjs
@@ -33,6 +33,7 @@ import { NETLIFYDEVLOG, NETLIFYDEVWARN } from './command-helpers.mjs'
 import createStreamPromise from './create-stream-promise.mjs'
 import { headersForPath, parseHeaders } from './headers.mjs'
 import { createRewriter, onChanges } from './rules-proxy.mjs'
+import { signRedirect } from './sign-redirect.mjs'
 
 const decompress = util.promisify(zlib.gunzip)
 const shouldGenerateETag = Symbol('Internal: response should generate ETag')
@@ -143,7 +144,7 @@ const alternativePathsFor = function (url) {
   return paths
 }
 
-const serveRedirect = async function ({ match, options, proxy, req, res }) {
+const serveRedirect = async function ({ match, options, proxy, req, res, siteInfo }) {
   if (!match) return proxy.web(req, res, options)
 
   options = options || req.proxyOptions || {}
@@ -155,6 +156,15 @@ const serveRedirect = async function ({ match, options, proxy, req, res }) {
     })
   }
 
+  if (match.signingSecret) {
+    req.headers['x-nf-sign'] = signRedirect({
+      deployContext: 'dev',
+      secret: match.signingSecret,
+      siteID: siteInfo.id,
+      siteURL: siteInfo.url,
+    })
+  }
+
   if (isFunction(options.functionsPort, req.url)) {
     return proxy.web(req, res, { target: options.functionsServer })
   }
@@ -306,7 +316,7 @@ const reqToURL = function (req, pathname) {
 
 const MILLISEC_TO_SEC = 1e3
 
-const initializeProxy = async function ({ configPath, distDir, host, port, projectDir }) {
+const initializeProxy = async function ({ configPath, distDir, host, port, projectDir, siteInfo }) {
   const proxy = httpProxy.createProxyServer({
     selfHandleResponse: true,
     target: {
@@ -370,13 +380,20 @@ const initializeProxy = async function ({ configPath, distDir, host, port, proje
         return proxy.web(req, res, req.proxyOptions)
       }
       if (req.proxyOptions && req.proxyOptions.match) {
-        return serveRedirect({ req, res, proxy: handlers, match: req.proxyOptions.match, options: req.proxyOptions })
+        return serveRedirect({
+          req,
+          res,
+          proxy: handlers,
+          match: req.proxyOptions.match,
+          options: req.proxyOptions,
+          siteInfo,
+        })
       }
     }
 
     if (req.proxyOptions.staticFile && isRedirect({ status: proxyRes.statusCode }) && proxyRes.headers.location) {
       req.url = proxyRes.headers.location
-      return serveRedirect({ req, res, proxy: handlers, match: null, options: req.proxyOptions })
+      return serveRedirect({ req, res, proxy: handlers, match: null, options: req.proxyOptions, siteInfo })
     }
 
     const responseData = []
@@ -472,7 +489,11 @@ const initializeProxy = async function ({ configPath, distDir, host, port, proje
   return handlers
 }
 
-const onRequest = async ({ addonsUrls, edgeFunctionsProxy, functionsServer, proxy, rewriter, settings }, req, res) => {
+const onRequest = async (
+  { addonsUrls, edgeFunctionsProxy, functionsServer, proxy, rewriter, settings, siteInfo },
+  req,
+  res,
+) => {
   req.originalBody = ['GET', 'OPTIONS', 'HEAD'].includes(req.method)
     ? null
     : await createStreamPromise(req, BYTES_LIMIT)
@@ -509,7 +530,7 @@ const onRequest = async ({ addonsUrls, edgeFunctionsProxy, functionsServer, prox
     // We don't want to generate an ETag for 3xx redirects.
     req[shouldGenerateETag] = ({ statusCode }) => statusCode < 300 || statusCode >= 400
 
-    return serveRedirect({ req, res, proxy, match, options })
+    return serveRedirect({ req, res, proxy, match, options, siteInfo })
   }
 
   // The request will be served by the framework server, which means we want to
@@ -570,6 +591,7 @@ export const startProxy = async function ({
     distDir: settings.dist,
     projectDir,
     configPath,
+    siteInfo,
   })
 
   const rewriter = await createRewriter({
@@ -588,6 +610,7 @@ export const startProxy = async function ({
     addonsUrls,
     functionsServer,
     edgeFunctionsProxy,
+    siteInfo,
   })
   const primaryServer = settings.https
     ? https.createServer({ cert: settings.https.cert, key: settings.https.key }, onRequestWithOptions)
diff --git a/src/utils/redirects.mjs b/src/utils/redirects.mjs
@@ -36,6 +36,7 @@ const normalizeRedirect = function ({
   conditions: { country, language, role, ...conditions },
   from,
   query,
+  signed,
   ...redirect
 }) {
   return {
@@ -48,5 +49,10 @@ const normalizeRedirect = function ({
       ...(country && { Country: country }),
       ...(language && { Language: language }),
     },
+    ...(signed && {
+      sign: {
+        jwt_secret: signed,
+      },
+    }),
   }
 }
diff --git a/src/utils/sign-redirect.mjs b/src/utils/sign-redirect.mjs
@@ -0,0 +1,16 @@
+import jwt from 'jsonwebtoken'
+
+// https://docs.netlify.com/routing/redirects/rewrites-proxies/#signed-proxy-redirects
+export const signRedirect = ({ deployContext, secret, siteID, siteURL }) => {
+  const claims = {
+    deploy_context: deployContext,
+    netlify_id: siteID,
+    site_url: siteURL,
+  }
+  const options = {
+    expiresIn: '5 minutes',
+    issuer: 'netlify',
+  }
+
+  return jwt.sign(claims, secret, options)
+}
diff --git a/tests/integration/0.command.dev.test.cjs b/tests/integration/0.command.dev.test.cjs
@@ -5,11 +5,13 @@ const { join } = require('path')
 // eslint-disable-next-line ava/use-test
 const avaTest = require('ava')
 const { isCI } = require('ci-info')
+const jwt = require('jsonwebtoken')
 const fetch = require('node-fetch')
 
 const { withDevServer } = require('./utils/dev-server.cjs')
 const { startExternalServer } = require('./utils/external-server.cjs')
 const got = require('./utils/got.cjs')
+const { withMockApi } = require('./utils/mock-api.cjs')
 const { withSiteBuilder } = require('./utils/site-builder.cjs')
 
 const test = isCI ? avaTest.serial.bind(avaTest) : avaTest
@@ -177,7 +179,9 @@ test('should rewrite requests to an external server', async (t) => {
 
     await withDevServer({ cwd: builder.directory }, async (server) => {
       const getResponse = await got(`${server.url}/api/ping`).json()
-      t.deepEqual(getResponse, { body: {}, method: 'GET', url: '/ping' })
+      t.deepEqual(getResponse.body, {})
+      t.is(getResponse.method, 'GET')
+      t.is(getResponse.url, '/ping')
 
       const postResponse = await got
         .post(`${server.url}/api/ping`, {
@@ -188,7 +192,79 @@ test('should rewrite requests to an external server', async (t) => {
           followRedirect: false,
         })
         .json()
-      t.deepEqual(postResponse, { body: { param: 'value' }, method: 'POST', url: '/ping' })
+      t.deepEqual(postResponse.body, { param: 'value' })
+      t.is(postResponse.method, 'POST')
+      t.is(postResponse.url, '/ping')
+    })
+
+    externalServer.close()
+  })
+})
+
+test('should sign external redirects with the `x-nf-sign` header when a `signed` value is set', async (t) => {
+  await withSiteBuilder('site-redirects-file-to-external', async (builder) => {
+    const mockSigningKey = 'iamverysecret'
+    const externalServer = startExternalServer()
+    const { port } = externalServer.address()
+    const siteInfo = {
+      account_slug: 'test-account',
+      id: 'site_id',
+      name: 'site-name',
+      url: 'https://cli-test-suite.netlify.ftw',
+    }
+    const routes = [
+      { path: 'sites/site_id', response: siteInfo },
+      { path: 'sites/site_id/service-instances', response: [] },
+      {
+        path: 'accounts',
+        response: [{ slug: siteInfo.account_slug }],
+      },
+    ]
+
+    await builder
+      .withNetlifyToml({
+        config: {
+          redirects: [{ from: '/sign/*', to: `http://localhost:${port}/:splat`, signed: mockSigningKey, status: 200 }],
+        },
+      })
+      .buildAsync()
+
+    await withMockApi(routes, async ({ apiUrl }) => {
+      await withDevServer(
+        {
+          cwd: builder.directory,
+          offline: false,
+          env: {
+            NETLIFY_API_URL: apiUrl,
+            NETLIFY_SITE_ID: siteInfo.id,
+            NETLIFY_AUTH_TOKEN: 'fake-token',
+          },
+        },
+        async (server) => {
+          const getResponse = await got(`${server.url}/sign/ping`).json()
+          const postResponse = await got
+            .post(`${server.url}/sign/ping`, {
+              headers: {
+                'Content-Type': 'application/x-www-form-urlencoded',
+              },
+              body: 'param=value',
+              followRedirect: false,
+            })
+            .json()
+
+          ;[getResponse, postResponse].forEach((response) => {
+            const signature = response.headers['x-nf-sign']
+            const payload = jwt.verify(signature, mockSigningKey)
+
+            t.is(payload.deploy_context, 'dev')
+            t.is(payload.netlify_id, siteInfo.id)
+            t.is(payload.site_url, siteInfo.url)
+            t.is(payload.iss, 'netlify')
+          })
+
+          t.deepEqual(postResponse.body, { param: 'value' })
+        },
+      )
     })
 
     externalServer.close()
@@ -206,11 +282,13 @@ test('should follow 301 redirect to an external server', async (t) => {
     await builder.buildAsync()
 
     await withDevServer({ cwd: builder.directory }, async (server) => {
-      const response = await got(`${server.url}/api/ping`, { followRedirect: false })
-      t.is(response.headers.location, `http://localhost:${port}/ping`)
+      const response1 = await got(`${server.url}/api/ping`, { followRedirect: false })
+      t.is(response1.headers.location, `http://localhost:${port}/ping`)
 
-      const body = await got(`${server.url}/api/ping`).json()
-      t.deepEqual(body, { body: {}, method: 'GET', url: '/ping' })
+      const response2 = await got(`${server.url}/api/ping`).json()
+      t.deepEqual(response2.body, {})
+      t.is(response2.method, 'GET')
+      t.is(response2.url, '/ping')
     })
 
     externalServer.close()
diff --git a/tests/integration/utils/external-server.cjs b/tests/integration/utils/external-server.cjs
@@ -4,7 +4,7 @@ const startExternalServer = () => {
   const app = express()
   app.use(express.urlencoded({ extended: true }))
   app.all('*', function onRequest(req, res) {
-    res.json({ url: req.url, body: req.body, method: req.method })
+    res.json({ url: req.url, body: req.body, method: req.method, headers: req.headers })
   })
 
   return app.listen()
