nix-config/modules/nixos/services/nginx/default.nix
2023-12-25 20:23:55 +01:00

470 lines
13 KiB
Nix

# A simple abstraction layer for almost all of my services' needs
{ config, lib, pkgs, ... }:
let
cfg = config.my.services.nginx;
domain = config.networking.domain;
virtualHostOption = with lib; types.submodule ({ name, ... }: {
options = {
subdomain = mkOption {
type = types.str;
default = name;
example = "dev";
description = ''
Which subdomain, under config.networking.domain, to use
for this virtual host.
'';
};
port = mkOption {
type = with types; nullOr port;
default = null;
example = 8080;
description = ''
Which port to proxy to, through 127.0.0.1, for this virtual host.
'';
};
redirect = mkOption {
type = with types; nullOr str;
default = null;
example = "https://example.com";
description = ''
Which domain to redirect to (301 response), for this virtual host.
'';
};
root = mkOption {
type = with types; nullOr path;
default = null;
example = "/var/www/blog";
description = ''
The root folder for this virtual host.
'';
};
socket = mkOption {
type = with types; nullOr path;
default = null;
example = "FIXME";
description = ''
The UNIX socket for this virtual host.
'';
};
sso = {
enable = mkEnableOption "SSO authentication";
};
extraConfig = mkOption {
type = types.attrs; # FIXME: forward type of virtualHosts
example = litteralExample ''
{
locations."/socket" = {
proxyPass = "http://127.0.0.1:8096/";
proxyWebsockets = true;
};
}
'';
default = { };
description = ''
Any extra configuration that should be applied to this virtual host.
'';
};
};
});
in
{
imports = [
./sso
];
options.my.services.nginx = with lib; {
enable = mkEnableOption "Nginx";
acme = {
credentialsFile = mkOption {
type = types.str;
example = "/var/lib/acme/creds.env";
description = ''
Gandi API key file as an 'EnvironmentFile' (see `systemd.exec(5)`)
'';
};
};
monitoring = {
enable = my.mkDisableOption "monitoring through grafana and prometheus";
};
virtualHosts = mkOption {
type = types.attrsOf virtualHostOption;
default = { };
example = litteralExample ''
{
gitea = {
subdomain = "git";
port = 8080;
};
dev = {
root = "/var/www/dev";
};
jellyfin = {
port = 8096;
extraConfig = {
locations."/socket" = {
proxyPass = "http://127.0.0.1:8096/";
proxyWebsockets = true;
};
};
};
}
'';
description = ''
List of virtual hosts to set-up using default settings.
'';
};
sso = {
authKeyFile = mkOption {
type = types.str;
example = "/var/lib/nginx-sso/auth-key.txt";
description = ''
Path to the auth key.
'';
};
subdomain = mkOption {
type = types.str;
default = "login";
example = "auth";
description = "Which subdomain, to use for SSO.";
};
port = mkOption {
type = types.port;
default = 8082;
example = 8080;
description = "Port to use for internal webui.";
};
users = mkOption {
type = types.attrsOf (types.submodule {
options = {
passwordHashFile = mkOption {
type = types.str;
example = "/var/lib/nginx-sso/alice/password-hash.txt";
description = "Path to file containing the user's password hash.";
};
totpSecretFile = mkOption {
type = types.str;
example = "/var/lib/nginx-sso/alice/totp-secret.txt";
description = "Path to file containing the user's TOTP secret.";
};
};
});
example = litteralExample ''
{
alice = {
passwordHashFile = "/var/lib/nginx-sso/alice/password-hash.txt";
totpSecretFile = "/var/lib/nginx-sso/alice/totp-secret.txt";
};
}
'';
description = "Definition of users";
};
groups = mkOption {
type = with types; attrsOf (listOf str);
example = litteralExample ''
{
root = [ "alice" ];
users = [ "alice" "bob" ];
}
'';
description = "Groups of users";
};
};
};
config = lib.mkIf cfg.enable {
assertions = [ ]
++ (lib.flip lib.mapAttrsToList cfg.virtualHosts (_: { subdomain, ... } @ args:
let
conflicts = [ "port" "root" "socket" "redirect" ];
optionsNotNull = builtins.map (v: args.${v} != null) conflicts;
optionsSet = lib.filter lib.id optionsNotNull;
in
{
assertion = builtins.length optionsSet == 1;
message = ''
Subdomain '${subdomain}' must have exactly one of ${
lib.concatStringsSep ", " (builtins.map (v: "'${v}'") conflicts)
} configured.
'';
}))
++ (
let
ports = lib.my.mapFilter
(v: v != null)
({ port, ... }: port)
(lib.attrValues cfg.virtualHosts);
portCounts = lib.my.countValues ports;
nonUniquesCounts = lib.filterAttrs (_: v: v != 1) portCounts;
nonUniques = builtins.attrNames nonUniquesCounts;
mkAssertion = port: {
assertion = false;
message = "Port ${port} cannot appear in multiple virtual hosts.";
};
in
map mkAssertion nonUniques
) ++ (
let
subs = lib.mapAttrsToList (_: { subdomain, ... }: subdomain) cfg.virtualHosts;
subsCounts = lib.my.countValues subs;
nonUniquesCounts = lib.filterAttrs (_: v: v != 1) subsCounts;
nonUniques = builtins.attrNames nonUniquesCounts;
mkAssertion = v: {
assertion = false;
message = ''
Subdomain '${v}' cannot appear in multiple virtual hosts.
'';
};
in
map mkAssertion nonUniques
)
;
services.nginx = {
enable = true;
statusPage = true; # For monitoring scraping.
recommendedBrotliSettings = true;
recommendedGzipSettings = true;
recommendedOptimisation = true;
recommendedProxySettings = true;
recommendedTlsSettings = true;
recommendedZstdSettings = true;
virtualHosts =
let
domain = config.networking.domain;
mkVHost = ({ subdomain, ... } @ args: lib.nameValuePair
"${subdomain}.${domain}"
(lib.my.recursiveMerge [
# Base configuration
{
forceSSL = true;
useACMEHost = domain;
}
# Proxy to port
(lib.optionalAttrs (args.port != null) {
locations."/".proxyPass =
"http://127.0.0.1:${toString args.port}";
})
# Serve filesystem content
(lib.optionalAttrs (args.root != null) {
inherit (args) root;
})
# Serve to UNIX socket
(lib.optionalAttrs (args.socket != null) {
locations."/".proxyPass =
"http://unix:${args.socket}";
})
# Redirect to a different domain
(lib.optionalAttrs (args.redirect != null) {
locations."/".return = "301 ${args.redirect}$request_uri";
})
# VHost specific configuration
args.extraConfig
# SSO configuration
(lib.optionalAttrs args.sso.enable {
extraConfig = (args.extraConfig.extraConfig or "") + ''
error_page 401 = @error401;
'';
locations."@error401".return = ''
302 https://${cfg.sso.subdomain}.${config.networking.domain}/login?go=$scheme://$http_host$request_uri
'';
locations."/" = {
extraConfig =
(args.extraConfig.locations."/".extraConfig or "") + ''
# Use SSO
auth_request /sso-auth;
# Set username through header
auth_request_set $username $upstream_http_x_username;
proxy_set_header X-User $username;
# Renew SSO cookie on request
auth_request_set $cookie $upstream_http_set_cookie;
add_header Set-Cookie $cookie;
'';
};
locations."/sso-auth" = {
proxyPass = "http://localhost:${toString cfg.sso.port}/auth";
extraConfig = ''
# Do not allow requests from outside
internal;
# Do not forward the request body
proxy_pass_request_body off;
proxy_set_header Content-Length "";
# Set X-Application according to subdomain for matching
proxy_set_header X-Application "${subdomain}";
# Set origin URI for matching
proxy_set_header X-Origin-URI $request_uri;
'';
};
})
])
);
in
lib.my.genAttrs' (lib.attrValues cfg.virtualHosts) mkVHost;
sso = {
enable = true;
configuration = {
listen = {
addr = "127.0.0.1";
inherit (cfg.sso) port;
};
audit_log = {
target = [
"fd://stdout"
];
events = [
"access_denied"
"login_success"
"login_failure"
"logout"
"validate"
];
headers = [
"x-origin-uri"
"x-application"
];
};
cookie = {
domain = ".${config.networking.domain}";
secure = true;
authentication_key = {
_secret = cfg.sso.authKeyFile;
};
};
login = {
title = "Ambroisie's SSO";
default_method = "simple";
hide_mfa_field = false;
names = {
simple = "Username / Password";
};
};
providers = {
simple =
let
applyUsers = lib.flip lib.mapAttrs cfg.sso.users;
in
{
users = applyUsers (_: v: { _secret = v.passwordHashFile; });
mfa = applyUsers (_: v: [{
provider = "totp";
attributes = {
secret = {
_secret = v.totpSecretFile;
};
};
}]);
inherit (cfg.sso) groups;
};
};
acl = {
rule_sets = [
{
rules = [{ field = "x-application"; present = true; }];
allow = [ "@root" ];
}
];
};
};
};
};
my.services.nginx.virtualHosts = {
login = {
inherit (cfg.sso) port;
};
};
networking.firewall.allowedTCPPorts = [ 80 443 ];
# Nginx needs to be able to read the certificates
users.users.nginx.extraGroups = [ "acme" ];
security.acme = {
defaults.email = lib.my.mkMailAddress "bruno.acme" "belanyi.fr";
acceptTerms = true;
# Use DNS wildcard certificate
certs =
{
"${domain}" = {
extraDomainNames = [ "*.${domain}" ];
dnsProvider = "gandiv5";
inherit (cfg.acme) credentialsFile;
};
};
};
systemd.services."acme-${domain}" = {
serviceConfig = {
Environment = [
# Since I do a "weird" setup with a wildcard CNAME
"LEGO_DISABLE_CNAME_SUPPORT=true"
];
};
};
services.grafana.provision.dashboards.settings.providers = lib.mkIf cfg.monitoring.enable [
{
name = "NGINX";
options.path = pkgs.nur.repos.alarsyo.grafanaDashboards.nginx;
disableDeletion = true;
}
];
services.prometheus = lib.mkIf cfg.monitoring.enable {
exporters.nginx = {
enable = true;
listenAddress = "127.0.0.1";
};
scrapeConfigs = [
{
job_name = "nginx";
static_configs = [
{
targets = [ "127.0.0.1:${toString config.services.prometheus.exporters.nginx.port}" ];
labels = {
instance = config.networking.hostName;
};
}
];
}
];
};
};
}