Add documentation to help section, rack_attack as example

.gitignore

@@ -20,6 +20,7 @@ Vagrantfile
 config/gitlab.yml
 config/database.yml
 config/initializers/omniauth.rb
+config/initializers/rack_attack.rb
 config/unicorn.rb
 config/resque.yml
 config/aws.yml

app/views/help/_layout.html.haml

@@ -30,5 +30,8 @@
         %li
           %strong= link_to "Public Access", help_public_access_path
 
+        %li
+          %strong= link_to "Security", help_security_path
+
   .span9.pull-right
     = yield

app/views/help/index.html.haml

@@ -79,3 +79,7 @@
         %li
           %strong= link_to "Public Access", help_public_access_path
           %p Learn how you can allow public access to a project.
+
+        %li
+          %strong= link_to "Security", help_security_path
+          %p Learn what you can do to secure your GitLab instance.

app/views/help/security.html.haml

@@ -0,0 +1,15 @@
+= render layout: 'help/layout' do
+  %h3.page-title Security
+
+  %p.slead
+    If your GitLab instance is visible from the internet chances are it will be 'tested' by bots sooner or later.
+    %br
+    %br
+    %br
+    .file-holder
+      .file-title
+        %i.icon-file
+        Dealing with bruteforcing
+      .file-content.wiki
+        = preserve do
+          = markdown File.read(Rails.root.join("doc", "security", "rack_attack.md"))

config/application.rb

@@ -78,7 +78,7 @@ class Application < Rails::Application
     #
     # config.relative_url_root = "/gitlab"
 
-    # Enable rack attack middleware
-    config.middleware.use Rack::Attack
+    # Uncomment to enable rack attack middleware
+    # config.middleware.use Rack::Attack
   end
 end

config/initializers/rack_attack.rb.example

@@ -0,0 +1,16 @@
+# To enable rack-attack for your GitLab instance do the following:
+# 1. In config/application.rb find and uncomment the following line:
+# config.middleware.use Rack::Attack
+# 2. Rename this file to rack_attack.rb
+# 3. Review the paths_to_be_protected and add any other path you need protecting
+# 4. Restart GitLab instance
+#
+
+paths_to_be_protected = [
+  "#{Rails.application.config.relative_url_root}/users/password",
+  "#{Rails.application.config.relative_url_root}/users/sign_in",
+  "#{Rails.application.config.relative_url_root}/users"
+]
+Rack::Attack.throttle('protected paths', limit: 6, period: 60.seconds) do |req|
+  req.ip if paths_to_be_protected.include?(req.path) && req.post?
+end

config/routes.rb

@@ -39,6 +39,7 @@
   get 'help/web_hooks'      => 'help#web_hooks'
   get 'help/workflow'       => 'help#workflow'
   get 'help/shortcuts'
+  get 'help/security'
 
   #
   # Global snippets

doc/security/rack_attack.md

@@ -0,0 +1,19 @@
+To prevent abusive clients doing damage GitLab uses rack-attack gem.
+If you installed or upgraded GitLab by following the official guides this should be enabled by default.
+If you are missing `config/initializers/rack_attack.rb` the following steps need to be taken in order to enable protection for your GitLab instance:
+
+1. In config/application.rb find and uncomment the following line:
+  config.middleware.use Rack::Attack
+2. Rename config/initializers/rack_attack.rb.example to config/initializers/rack_attack.rb
+3. Review the paths_to_be_protected and add any other path you need protecting
+4. Restart GitLab instance
+
+By default, user sign-in, user sign-up(if enabled) and user password reset is limited to 6 requests per minute.
+After trying for 6 times, client will have to wait for the next minute to be able to try again.
+These settings can be found in `config/initializers/rack_attack.rb`
+
+If you want more restrictive/relaxed throttle rule change the `limit` or `period` values. For example, more relaxed throttle rule will be if you set limit: 3 and period: 1.second(this will allow 3 requests per second). You can also add other paths to the protected list by adding to `paths_to_be_protected` variable. If you change any of these settings do not forget to restart your GitLab instance.
+
+In case you find throttling is not enough to protect you against abusive clients, rack-attack gem offers IP whitelisting, blacklisting, Fail2ban style filter and tracking.
+
+For more information on how to use these options check out [rack-attack README](https://github.com/kickstarter/rack-attack/blob/master/README.md).