From e91244099eac3abb9c9d714b7c785380eacf89b3 Mon Sep 17 00:00:00 2001
From: Tom Hughes <tom@compton.nu>
Date: Thu, 11 Jul 2024 13:27:32 +0100
Subject: [PATCH] Look through cloudflare to get real client IPs

---
 cookbooks/web/recipes/frontend.rb             | 20 ++++++++++++++++++-
 .../web/templates/default/apache.frontend.erb |  6 ++++++
 2 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/cookbooks/web/recipes/frontend.rb b/cookbooks/web/recipes/frontend.rb
index ec7ce92f5..f9e733c5b 100644
--- a/cookbooks/web/recipes/frontend.rb
+++ b/cookbooks/web/recipes/frontend.rb
@@ -34,6 +34,7 @@ apache_module "proxy"
 apache_module "proxy_fcgi"
 apache_module "lbmethod_byrequests"
 apache_module "lbmethod_bybusyness"
+apache_module "remoteip"
 apache_module "reqtimeout"
 apache_module "rewrite"
 apache_module "unique_id"
@@ -52,9 +53,26 @@ remote_directory "#{node[:web][:base_directory]}/static" do
   files_mode "644"
 end
 
+remote_file "#{Chef::Config[:file_cache_path]}/cloudflare-ipv4-list" do
+  source "https://www.cloudflare.com/ips-v4"
+  compile_time true
+  ignore_failure true
+end
+
+cloudflare_ipv4 = IO.read("#{Chef::Config[:file_cache_path]}/cloudflare-ipv4-list").lines.map(&:chomp)
+
+remote_file "#{Chef::Config[:file_cache_path]}/cloudflare-ipv6-list" do
+  source "https://www.cloudflare.com/ips-v6"
+  compile_time true
+  ignore_failure true
+end
+
+cloudflare_ipv6 = IO.read("#{Chef::Config[:file_cache_path]}/cloudflare-ipv6-list").lines.map(&:chomp)
+
 apache_site "www.openstreetmap.org" do
   template "apache.frontend.erb"
-  variables :status => node[:web][:status],
+  variables :cloudflare => cloudflare_ipv4 + cloudflare_ipv6,
+            :status => node[:web][:status],
             :secret_key_base => web_passwords["secret_key_base"]
 end
 
diff --git a/cookbooks/web/templates/default/apache.frontend.erb b/cookbooks/web/templates/default/apache.frontend.erb
index fb677769e..9a2cd10a7 100644
--- a/cookbooks/web/templates/default/apache.frontend.erb
+++ b/cookbooks/web/templates/default/apache.frontend.erb
@@ -26,6 +26,12 @@ ErrorLog /var/log/apache2/error.log
   SSLCertificateFile /etc/ssl/certs/www.openstreetmap.org.pem
   SSLCertificateKeyFile /etc/ssl/private/www.openstreetmap.org.key
 
+  # Get the real remote IP for requests via a trusted proxy
+  RemoteIPHeader CF-Connecting-IP
+<% @cloudflare.sort.each do |address| -%>
+  RemoteIPTrustedProxy <%= address %>
+<% end -%>
+
   #
   # Turn on various features
   #
-- 
2.39.5