# This is a sample configuration for Snuffleupagus to accommodate Xenforo v2.2.12 on PHP 8.1
# We keep the default configuration values commented out where they have been shown to be harmful

# Global configuration variables
sp.global.secret_key("YOU _DO_ NEED TO CHANGE THIS WITH SOME RANDOM CHARACTERS.");

# Enforce secure cookies
# -- You ought to be using HTTPS-only anyway
sp.auto_cookie_secure.enable();

# Harden the PRNG
sp.harden_random.enable();

# Disabled XXE
sp.xxe_protection.enable();

# Globally activate strict mode
# -- Entirely breaks Xenforo; 99% of requests abuse lose typing directly in their entrypoint
# sp.global_strict.enable();

# Prevent unserialize-related exploits
# -- Xenforo heavily uses serialization in database and caches; enable at your own risk
# sp.unserialize_hmac.enable();

# Only allow execution of read-only files. This is a low-hanging fruit that you should enable.
# -- Xenforo has a 0777 file permissions model and will refuse to run with anything else, both for
# -- code caches and its own webroot; this isn't workable at all with this
# sp.readonly_exec.enable();

# PHP has a lot of wrappers, most of them aren't usually useful, you should
# only enable the ones you're using.
# -- Seems OK in general, could break somewhere along the way however
sp.wrappers_whitelist.list("file,php,phar");

# Prevent sloppy comparisons.
sp.sloppy_comparison.enable();

# use SameSite on session cookie
# https://snuffleupagus.readthedocs.io/features.html#protection-against-cross-site-request-forgery
sp.cookie.name("PHPSESSID").samesite("lax");
# -- Xenforo cookies
sp.cookie.name("xf_csrf").samesite("lax");
sp.cookie.name("xf_session").samesite("lax");
sp.cookie.name("xf_user").samesite("lax");

# Harden the `chmod` function
# -- Xenforo aggressively makes files executable left and right, alas
# sp.disable_function.function("chmod").param("mode").value_r("^[0-9]{2}[67]$").drop();

# Prevent various `mail`-related vulnerabilities
sp.disable_function.function("mail").param("additional_parameters").value_r("\\-").drop();

# Since it's now burned, me might as well mitigate it publicly
sp.disable_function.function("putenv").param("assignment").value_r("LD_").drop()

# This one was burned in Nov 2019 - https://gist.github.com/LoadLow/90b60bd5535d6c3927bb24d5f9955b80
sp.disable_function.function("putenv").param("assignment").value_r("GCONV_").drop()

# Since people are stupid enough to use `extract` on things like $_GET or $_POST, we might as well mitigate this vector
sp.disable_function.function("extract").param("array").value_r("^_").drop()
sp.disable_function.function("extract").param("flags").value("0").drop()

# This is also burned:
# ini_set('open_basedir','..');chdir('..');…;chdir('..');ini_set('open_basedir','/');echo(file_get_contents('/etc/passwd'));
# Since we have no way of matching on two parameters at the same time, we're
# blocking calls to open_basedir altogether: nobody is using it via ini_set anyway.
# Moreover, there are non-public bypasses that are also using this vector ;)
sp.disable_function.function("ini_set").param("option").value_r("open_basedir").drop()

##Prevent various `include`-related vulnerabilities
# -- "php8" is necessary here, due to the following snippet in one of the vendored Symfony dependencies
# -- if (PHP_VERSION_ID >= 80000) {
# --     require_once __DIR__.'/Resources/mb_convert_variables.php8';
# -- }
sp.disable_function.function("require_once").value_r("\.(inc|phtml|php|php8)$").allow();
sp.disable_function.function("include_once").value_r("\.(inc|phtml|php)$").allow();
sp.disable_function.function("require").value_r("\.(inc|phtml|php)$").allow();
sp.disable_function.function("include").value_r("\.(inc|phtml|php)$").allow();
sp.disable_function.function("require_once").drop()
sp.disable_function.function("include_once").drop()
sp.disable_function.function("require").drop()
sp.disable_function.function("include").drop()

# Prevent `system`-related injections
sp.disable_function.function("system").param("command").value_r("[$|;&`\\n\\(\\)\\\\]").drop();
sp.disable_function.function("shell_exec").param("command").value_r("[$|;&`\\n\\(\\)\\\\]").drop();
sp.disable_function.function("exec").param("command").value_r("[$|;&`\\n\\(\\)\\\\]").drop();
sp.disable_function.function("proc_open").param("command").value_r("[$|;&`\\n\\(\\)\\\\]").drop();

# Prevent runtime modification of interesting things
# -- Xenforo applies its own set of ini rules sanitization and this cannot be disabled without a hard fork
# sp.disable_function.function("ini_set").param("option").value("assert.active").drop();
# sp.disable_function.function("ini_set").param("option").value("zend.assertions").drop();
# sp.disable_function.function("ini_set").param("option").value("memory_limit").drop();
sp.disable_function.function("ini_set").param("option").value("include_path").drop();
sp.disable_function.function("ini_set").param("option").value("open_basedir").drop();

# Detect some backdoors via environment recon
# -- Xenforo does its own recon of the environment and this cannot be disabled without a hard fork
# sp.disable_function.function("ini_get").param("option").value("allow_url_fopen").drop();
# sp.disable_function.function("ini_get").param("option").value("open_basedir").drop();
sp.disable_function.function("ini_get").param("option").value_r("suhosin").drop();
sp.disable_function.function("function_exists").param("function").value("eval").drop();
sp.disable_function.function("function_exists").param("function").value("exec").drop();
sp.disable_function.function("function_exists").param("function").value("system").drop();
sp.disable_function.function("function_exists").param("function").value("shell_exec").drop();
sp.disable_function.function("function_exists").param("function").value("proc_open").drop();
sp.disable_function.function("function_exists").param("function").value("passthru").drop();
sp.disable_function.function("is_callable").param("value").value("eval").drop();
sp.disable_function.function("is_callable").param("value").value("exec").drop();
sp.disable_function.function("is_callable").param("value").value("system").drop();
sp.disable_function.function("is_callable").param("value").value("shell_exec").drop();
sp.disable_function.function("is_callable").param("value").value("proc_open").drop();
sp.disable_function.function("is_callable").param("value").value("passthru").drop();

# Ghetto error-based sqli detection
sp.disable_function.function("mysql_query").ret("FALSE").drop();
sp.disable_function.function("mysqli_query").ret("FALSE").drop();
sp.disable_function.function("PDO::query").ret("FALSE").drop();

# Ensure that certificates are properly verified
sp.disable_function.function("curl_setopt").param("value").value("1").allow();
sp.disable_function.function("curl_setopt").param("value").value("2").allow();
# `81` is SSL_VERIFYHOST and `64` SSL_VERIFYPEER
sp.disable_function.function("curl_setopt").param("option").value("64").drop().alias("Please don't turn CURLOPT_SSL_VERIFYCLIENT off.");
sp.disable_function.function("curl_setopt").param("option").value("81").drop().alias("Please don't turn CURLOPT_SSL_VERIFYHOST off.");

# File upload
sp.disable_function.function("move_uploaded_file").param("destination").value_r("\\.ph").drop();
sp.disable_function.function("move_uploaded_file").param("destination").value_r("\\.ht").drop();

# Logging lockdown
# -- Xenforo applies its own set of ini rules sanitization and this cannot be disabled without a hard fork
# sp.disable_function.function("ini_set").param("option").value_r("error_log").drop()
# sp.disable_function.function("ini_set").param("option").value_r("error_reporting").drop()
# sp.disable_function.function("ini_set").param("option").value_r("display_errors").drop()

# Configuration you might want to enable on production environments only
# sp.ini.key("display_errors").set("0").ro();
# sp.ini.key("display_startup_errors").set("0").ro();
# sp.ini.key("expose_php").set("0").ro();