Remove Rack Attack monkey patches and bump to version 4.3.0

CHANGELOG

 Please view this file on the master branch, on stable branches it's out of date.
 v 7.12.0 (unreleased)
+  - Remove Rack Attack monkey patches and bump to version 4.3.0 (Stan Hu)
   - Allow to configure location of the `.gitlab_shell_secret` file. (Jakub Jirutka)
   - Disabled expansion of top/bottom blobs for new file diffs
   - Update Asciidoctor gem to version 1.5.2. (Jakub Jirutka)

Gemfile

@@ -172,7 +172,7 @@ gem "underscore-rails", "~> 1.4.4"
 gem "sanitize", '~> 2.0'
 # Protect against bruteforcing
-gem "rack-attack"
+gem "rack-attack", '~> 4.3.0'
 # Ace editor
 gem 'ace-rails-ap'

Gemfile.lock

@@ -421,7 +421,7 @@ GEM
     rack (1.5.2)
     rack-accept (0.4.5)
       rack (>= 0.4)
-    rack-attack (4.2.0)
+    rack-attack (4.3.0)
       rack
     rack-cors (0.2.9)
     rack-mini-profiler (0.9.0)
@@ -764,7 +764,7 @@ DEPENDENCIES
   poltergeist (~> 1.5.1)
   pry-rails
   quiet_assets (~> 1.0.1)
-  rack-attack
+  rack-attack (~> 4.3.0)
   rack-cors
   rack-mini-profiler
   rack-oauth2 (~> 1.0.5)

lib/gitlab/backend/grack_auth.rb

-require_relative 'rack_attack_helpers'
 require_relative 'shell_env'
 module Grack

lib/gitlab/backend/rack_attack_helpers.rb

-# rack-attack v4.2.0 doesn't yet support clearing of keys.
-# Taken from https://github.com/kickstarter/rack-attack/issues/113
-class Rack::Attack::Allow2Ban
-  def self.reset(discriminator, options)
-    findtime = options[:findtime] or raise ArgumentError, "Must pass findtime option"
-
-    cache.reset_count("#{key_prefix}:count:#{discriminator}", findtime)
-    cache.delete("#{key_prefix}:ban:#{discriminator}")
-  end
-end
-
-class Rack::Attack::Cache
-  def reset_count(unprefixed_key, period)
-    epoch_time = Time.now.to_i
-    # Add 1 to expires_in to avoid timing error: http://git.io/i1PHXA
-    expires_in = period - (epoch_time % period) + 1
-    key = "#{(epoch_time / period).to_i}:#{unprefixed_key}"
-    delete(key)
-  end
-
-  def delete(unprefixed_key)
-    store.delete("#{prefix}:#{unprefixed_key}")
-  end
-end
-
-class Rack::Attack::StoreProxy::RedisStoreProxy
-  def delete(key, options={})
-    self.del(key)
-    rescue Redis::BaseError
-  end
-end

spec/lib/gitlab/backend/grack_auth_spec.rb

@@ -156,7 +156,7 @@ describe Grack::Auth do
                   end
                   expect(attempt_login(true)).to eq(200)
-                  expect(Rack::Attack::Allow2Ban.send(:banned?, ip)).to eq(nil)
+                  expect(Rack::Attack::Allow2Ban.banned?(ip)).to be_falsey
                   for n in 0..maxretry do
                     expect(attempt_login(false)).to eq(401)

spec/lib/gitlab/backend/rack_attack_helpers_spec.rb

-require "spec_helper"
-
-describe 'RackAttackHelpers' do
-  describe 'reset' do
-    let(:discriminator) { 'test-key'}
-    let(:maxretry) { 5 }
-    let(:period) { 1.minute }
-    let(:options) { { findtime: period, bantime: 60, maxretry: maxretry } }
-
-    def do_filter
-      for i in 1..maxretry - 1 do
-        status = Rack::Attack::Allow2Ban.filter(discriminator, options) { true }
-        expect(status).to eq(false)
-      end
-    end
-
-    def do_reset
-      Rack::Attack::Allow2Ban.reset(discriminator, options)
-    end
-
-    before do
-      do_reset
-    end
-
-    after do
-      do_reset
-    end
-
-    it 'user is not banned after n - 1 retries' do
-      do_filter
-      do_reset
-      do_filter
-    end
-  end
-end