🔒 Fixed rate limiting for user login (#15336)

refs https://github.com/TryGhost/Team/issues/1074

Rather than relying on the global block to stop malicious actors from
enumerating email addresses to determine who is and isn't a user, we
want our user login brute force protection to be on an IP basis,
rather than tied to the username.

ghost/core/core/server/web/shared/middleware/brute.js

@@ -29,26 +29,13 @@ module.exports = {
         })(req, res, next);
     },
     /**
-     * block per user
-     * username === email!
+     * block per ip
      */
     userLogin(req, res, next) {
         return spamPrevention.userLogin().getMiddleware({
             ignoreIP: false,
             key(_req, _res, _next) {
-                if (_req.body.username) {
-                    return _next(`${_req.body.username}login`);
-                }
-
-                if (_req.body.authorizationCode) {
-                    return _next(`${_req.body.authorizationCode}login`);
-                }
-
-                if (_req.body.refresh_token) {
-                    return _next(`${_req.body.refresh_token}login`);
-                }
-
-                return _next();
+                return _next('user_login');
             }
         })(req, res, next);
     },

ghost/core/test/e2e-api/admin/__snapshots__/rate-limiting.test.js.snap

@@ -0,0 +1,25 @@
+// Jest Snapshot v1, https://goo.gl/fbAQLP
+
+exports[`Sessions API Is rate limited to protect against brute forcing a users password 1: [headers] 1`] = `
+Object {
+  "access-control-allow-origin": "http://127.0.0.1:2369",
+  "cache-control": "no-cache, private, no-store, must-revalidate, max-stale=0, post-check=0, pre-check=0",
+  "content-length": "286",
+  "content-type": "application/json; charset=utf-8",
+  "etag": StringMatching /\\(\\?:W\\\\/\\)\\?"\\(\\?:\\[ !#-\\\\x7E\\\\x80-\\\\xFF\\]\\*\\|\\\\r\\\\n\\[\\\\t \\]\\|\\\\\\\\\\.\\)\\*"/,
+  "vary": "Origin, Accept-Encoding",
+  "x-powered-by": "Express",
+}
+`;
+
+exports[`Sessions API Is rate limited to protect against brute forcing whether a user exists 1: [headers] 1`] = `
+Object {
+  "access-control-allow-origin": "http://127.0.0.1:2369",
+  "cache-control": "no-cache, private, no-store, must-revalidate, max-stale=0, post-check=0, pre-check=0",
+  "content-length": "286",
+  "content-type": "application/json; charset=utf-8",
+  "etag": StringMatching /\\(\\?:W\\\\/\\)\\?"\\(\\?:\\[ !#-\\\\x7E\\\\x80-\\\\xFF\\]\\*\\|\\\\r\\\\n\\[\\\\t \\]\\|\\\\\\\\\\.\\)\\*"/,
+  "vary": "Origin, Accept-Encoding",
+  "x-powered-by": "Express",
+}
+`;

ghost/core/test/e2e-api/admin/rate-limiting.test.js

@@ -0,0 +1,74 @@
+const {
+    agentProvider,
+    fixtureManager,
+    matchers: {
+        anyEtag
+    },
+    dbUtils,
+    configUtils
+} = require('../../utils/e2e-framework');
+
+describe('Sessions API', function () {
+    let agent;
+
+    before(async function () {
+        agent = await agentProvider.getAdminAPIAgent();
+        await fixtureManager.init();
+    });
+
+    it('Is rate limited to protect against brute forcing a users password', async function () {
+        await dbUtils.truncate('brute');
+        // +1 because this is a retry count, so we have one request + the retries, then blocked
+        const userLoginRateLimit = configUtils.config.get('spam').user_login.freeRetries + 1;
+
+        for (let i = 0; i < userLoginRateLimit; i++) {
+            await agent
+                .post('session/')
+                .body({
+                    grant_type: 'password',
+                    username: 'user@domain.tld',
+                    password: 'parseword'
+                });
+        }
+
+        await agent
+            .post('session/')
+            .body({
+                grant_type: 'password',
+                username: 'user@domain.tld',
+                password: 'parseword'
+            })
+            .expectStatus(429)
+            .matchHeaderSnapshot({
+                etag: anyEtag
+            });
+    });
+
+    it('Is rate limited to protect against brute forcing whether a user exists', async function () {
+        await dbUtils.truncate('brute');
+        // +1 because this is a retry count, so we have one request + the retries, then blocked
+        const userLoginRateLimit = configUtils.config.get('spam').user_login.freeRetries + 1;
+
+        for (let i = 0; i < userLoginRateLimit; i++) {
+            await agent
+                .post('session/')
+                .body({
+                    grant_type: 'password',
+                    username: `user+${i}@domain.tld`,
+                    password: `parseword`
+                });
+        }
+
+        await agent
+            .post('session/')
+            .body({
+                grant_type: 'password',
+                username: 'user@domain.tld',
+                password: 'parseword'
+            })
+            .expectStatus(429)
+            .matchHeaderSnapshot({
+                etag: anyEtag
+            });
+    });
+});