# This module is necessary for hosts that are serving through Cloudflare. # Cloudflare is a CDN service that is used to serve the domain names and # caching for my websites and services. Since Cloudflare acts as our proxy, we # must allow access over the Internet from Cloudflare's IP ranges. # We also want to validate our HTTPS certificates from Caddy. We'll use Caddy's # DNS validation plugin to connect to Cloudflare and automatically create # validation DNS records for our generated certificates. { config, pkgs, lib, ... }: let cloudflareIpRanges = [ # Cloudflare IPv4: https://www.cloudflare.com/ips-v4 "173.245.48.0/20" "103.21.244.0/22" "103.22.200.0/22" "103.31.4.0/22" "141.101.64.0/18" "108.162.192.0/18" "190.93.240.0/20" "188.114.96.0/20" "197.234.240.0/22" "198.41.128.0/17" "162.158.0.0/15" "104.16.0.0/13" "104.24.0.0/14" "172.64.0.0/13" "131.0.72.0/22" # Cloudflare IPv6: https://www.cloudflare.com/ips-v6 "2400:cb00::/32" "2606:4700::/32" "2803:f800::/32" "2405:b500::/32" "2405:8100::/32" "2a06:98c0::/29" "2c0f:f248::/32" ]; in { options.cloudflare.enable = lib.mkEnableOption "Use Cloudflare."; options.cloudflare.noProxyDomains = lib.mkOption { type = lib.types.listOf lib.types.str; description = "Domains to use for dyndns without CDN proxying."; default = [ ]; }; config = lib.mkIf config.cloudflare.enable { # Forces Caddy to error if coming from a non-Cloudflare IP caddy.cidrAllowlist = cloudflareIpRanges; # Tell Caddy to use Cloudflare DNS for ACME challenge validation services.caddy.package = pkgs.caddy-cloudflare; # Patched overlay caddy.tlsPolicies = [{ issuers = [{ module = "acme"; challenges = { dns = { provider = { name = "cloudflare"; api_token = "{env.CLOUDFLARE_API_TOKEN}"; }; resolvers = [ "1.1.1.1" ]; }; }; }]; }]; # Allow Caddy to read Cloudflare API key for DNS validation systemd.services.caddy.serviceConfig.EnvironmentFile = config.secrets.cloudflare-api.dest; # API key must have access to modify Cloudflare DNS records secrets.cloudflare-api = { source = ../../../private/cloudflare-api.age; dest = "${config.secretsDirectory}/cloudflare-api"; owner = "caddy"; group = "caddy"; }; # Wait for secret to exist systemd.services.caddy = { after = [ "cloudflare-api-secret.service" ]; requires = [ "cloudflare-api-secret.service" ]; }; # Allows Nextcloud to trust Cloudflare IPs services.nextcloud.settings.trusted_proxies = cloudflareIpRanges; # Allows Transmission to trust Cloudflare IPs services.transmission.settings.rpc-whitelist = builtins.concatStringsSep "," ([ "127.0.0.1" ] ++ cloudflareIpRanges); services.cloudflare-dyndns = lib.mkIf ((builtins.length config.services.cloudflare-dyndns.domains) > 0) { enable = true; proxied = true; deleteMissing = true; apiTokenFile = config.secrets.cloudflare-api.dest; }; # Wait for secret to exist to start systemd.services.cloudflare-dyndns = lib.mkIf config.services.cloudflare-dyndns.enable { after = [ "cloudflare-api-secret.service" ]; requires = [ "cloudflare-api-secret.service" ]; }; # Run a second copy of dyn-dns for non-proxied domains # Adapted from: https://github.com/NixOS/nixpkgs/blob/nixos-unstable/nixos/modules/services/networking/cloudflare-dyndns.nix systemd.services.cloudflare-dyndns-noproxy = lib.mkIf ((builtins.length config.cloudflare.noProxyDomains) > 0) { description = "CloudFlare Dynamic DNS Client (no proxy)"; after = [ "network.target" "cloudflare-api-secret.service" ]; requires = [ "cloudflare-api-secret.service" ]; wantedBy = [ "multi-user.target" ]; startAt = "*:0/5"; environment = { CLOUDFLARE_DOMAINS = toString config.cloudflare.noProxyDomains; }; serviceConfig = { Type = "simple"; DynamicUser = true; StateDirectory = "cloudflare-dyndns-noproxy"; EnvironmentFile = config.services.cloudflare-dyndns.apiTokenFile; ExecStart = let args = [ "--cache-file /var/lib/cloudflare-dyndns-noproxy/ip.cache" ] ++ (if config.services.cloudflare-dyndns.ipv4 then [ "-4" ] else [ "-no-4" ]) ++ (if config.services.cloudflare-dyndns.ipv6 then [ "-6" ] else [ "-no-6" ]) ++ lib.optional config.services.cloudflare-dyndns.deleteMissing "--delete-missing"; in "${pkgs.cloudflare-dyndns}/bin/cloudflare-dyndns ${toString args}"; }; }; }; }