Merge branch 'trusted-proxies-ip-addr' into 'master'

Pass trusted_proxies to action_dispatch as IPAddrs instead of strings

Without this setting your own trusted_proxies does not work.

Fixes an issue introduce in: https://gitlab.com/gitlab-org/gitlab-ce/merge_requests/3524

Fixes: https://gitlab.com/gitlab-org/gitlab-ce/issues/17004

See merge request !3970

config/initializers/trusted_proxies.rb

-Rails.application.config.action_dispatch.trusted_proxies =
+Rails.application.config.action_dispatch.trusted_proxies = (
   [ '127.0.0.1', '::1' ] + Array(Gitlab.config.gitlab.trusted_proxies)
+).map { |proxy| IPAddr.new(proxy) }

spec/initializers/trusted_proxies_spec.rb

+require 'spec_helper'
+
+describe 'trusted_proxies', lib: true do
+  context 'with default config' do
+    before do
+      set_trusted_proxies([])
+    end
+
+    it 'preserves private IPs as remote_ip' do
+      request = stub_request('HTTP_X_FORWARDED_FOR' => '10.1.5.89')
+      expect(request.remote_ip).to eq('10.1.5.89')
+    end
+
+    it 'filters out localhost from remote_ip' do
+      request = stub_request('HTTP_X_FORWARDED_FOR' => '1.1.1.1, 10.1.5.89, 127.0.0.1')
+      expect(request.remote_ip).to eq('10.1.5.89')
+    end
+  end
+
+  context 'with private IP ranges added' do
+    before do
+      set_trusted_proxies([ "10.0.0.0/8", "172.16.0.0/12", "192.168.0.0/16" ])
+    end
+
+    it 'filters out private and local IPs from remote_ip' do
+      request = stub_request('HTTP_X_FORWARDED_FOR' => '1.2.3.6, 1.1.1.1, 10.1.5.89, 127.0.0.1')
+      expect(request.remote_ip).to eq('1.1.1.1')
+    end
+  end
+
+  context 'with proxy IP added' do
+    before do
+      set_trusted_proxies([ "60.98.25.47" ])
+    end
+
+    it 'filters out proxy IP from remote_ip' do
+      request = stub_request('HTTP_X_FORWARDED_FOR' => '1.2.3.6, 1.1.1.1, 60.98.25.47, 127.0.0.1')
+      expect(request.remote_ip).to eq('1.1.1.1')
+    end
+  end
+
+  def stub_request(headers = {})
+    ActionDispatch::RemoteIp.new(Proc.new { }, false, Rails.application.config.action_dispatch.trusted_proxies).call(headers)
+    ActionDispatch::Request.new(headers)
+  end
+
+  def set_trusted_proxies(proxies = [])
+    stub_config_setting('trusted_proxies' => proxies)
+    load File.join(__dir__, '../../config/initializers/trusted_proxies.rb')
+  end
+end