nixpkgs/nixos/tests/acme.nix
Martin Weinelt dc940ecdb3
Merge pull request #121750 from m1cr0man/master
nixos/acme: Ensure certs are always protected
2021-07-06 15:10:54 +02:00

442 lines
18 KiB
Nix

let
commonConfig = ./common/acme/client;
dnsServerIP = nodes: nodes.dnsserver.config.networking.primaryIPAddress;
dnsScript = {pkgs, nodes}: let
dnsAddress = dnsServerIP nodes;
in pkgs.writeShellScript "dns-hook.sh" ''
set -euo pipefail
echo '[INFO]' "[$2]" 'dns-hook.sh' $*
if [ "$1" = "present" ]; then
${pkgs.curl}/bin/curl --data '{"host": "'"$2"'", "value": "'"$3"'"}' http://${dnsAddress}:8055/set-txt
else
${pkgs.curl}/bin/curl --data '{"host": "'"$2"'"}' http://${dnsAddress}:8055/clear-txt
fi
'';
documentRoot = pkgs: pkgs.runCommand "docroot" {} ''
mkdir -p "$out"
echo hello world > "$out/index.html"
'';
vhostBase = pkgs: {
forceSSL = true;
locations."/".root = documentRoot pkgs;
};
in import ./make-test-python.nix ({ lib, ... }: {
name = "acme";
meta.maintainers = lib.teams.acme.members;
nodes = {
# The fake ACME server which will respond to client requests
acme = { nodes, lib, ... }: {
imports = [ ./common/acme/server ];
networking.nameservers = lib.mkForce [ (dnsServerIP nodes) ];
};
# A fake DNS server which can be configured with records as desired
# Used to test DNS-01 challenge
dnsserver = { nodes, pkgs, ... }: {
networking.firewall.allowedTCPPorts = [ 8055 53 ];
networking.firewall.allowedUDPPorts = [ 53 ];
systemd.services.pebble-challtestsrv = {
enable = true;
description = "Pebble ACME challenge test server";
wantedBy = [ "network.target" ];
serviceConfig = {
ExecStart = "${pkgs.pebble}/bin/pebble-challtestsrv -dns01 ':53' -defaultIPv6 '' -defaultIPv4 '${nodes.webserver.config.networking.primaryIPAddress}'";
# Required to bind on privileged ports.
AmbientCapabilities = [ "CAP_NET_BIND_SERVICE" ];
};
};
};
# A web server which will be the node requesting certs
webserver = { pkgs, nodes, lib, config, ... }: {
imports = [ commonConfig ];
networking.nameservers = lib.mkForce [ (dnsServerIP nodes) ];
networking.firewall.allowedTCPPorts = [ 80 443 ];
# OpenSSL will be used for more thorough certificate validation
environment.systemPackages = [ pkgs.openssl ];
# Set log level to info so that we can see when the service is reloaded
services.nginx.enable = true;
services.nginx.logError = "stderr info";
# First tests configure a basic cert and run a bunch of openssl checks
services.nginx.virtualHosts."a.example.test" = (vhostBase pkgs) // {
enableACME = true;
};
# Used to determine if service reload was triggered
systemd.targets.test-renew-nginx = {
wants = [ "acme-a.example.test.service" ];
after = [ "acme-a.example.test.service" "nginx-config-reload.service" ];
};
# Test that account creation is collated into one service
specialisation.account-creation.configuration = { nodes, pkgs, lib, ... }: let
email = "newhostmaster@example.test";
caDomain = nodes.acme.config.test-support.acme.caDomain;
# Exit 99 to make it easier to track if this is the reason a renew failed
testScript = ''
test -e accounts/${caDomain}/${email}/account.json || exit 99
'';
in {
security.acme.email = lib.mkForce email;
systemd.services."b.example.test".preStart = testScript;
systemd.services."c.example.test".preStart = testScript;
services.nginx.virtualHosts."b.example.test" = (vhostBase pkgs) // {
enableACME = true;
};
services.nginx.virtualHosts."c.example.test" = (vhostBase pkgs) // {
enableACME = true;
};
};
# Cert config changes will not cause the nginx configuration to change.
# This tests that the reload service is correctly triggered.
# It also tests that postRun is exec'd as root
specialisation.cert-change.configuration = { pkgs, ... }: {
security.acme.certs."a.example.test".keyType = "ec384";
security.acme.certs."a.example.test".postRun = ''
set -euo pipefail
touch test
chown root:root test
echo testing > test
'';
};
# Now adding an alias to ensure that the certs are updated
specialisation.nginx-aliases.configuration = { pkgs, ... }: {
services.nginx.virtualHosts."a.example.test" = {
serverAliases = [ "b.example.test" ];
};
};
# Test OCSP Stapling
specialisation.ocsp-stapling.configuration = { pkgs, ... }: {
security.acme.certs."a.example.test" = {
ocspMustStaple = true;
};
services.nginx.virtualHosts."a.example.com" = {
extraConfig = ''
ssl_stapling on;
ssl_stapling_verify on;
'';
};
};
# Test using Apache HTTPD
specialisation.httpd-aliases.configuration = { pkgs, config, lib, ... }: {
services.nginx.enable = lib.mkForce false;
services.httpd.enable = true;
services.httpd.adminAddr = config.security.acme.email;
services.httpd.virtualHosts."c.example.test" = {
serverAliases = [ "d.example.test" ];
forceSSL = true;
enableACME = true;
documentRoot = documentRoot pkgs;
};
# Used to determine if service reload was triggered
systemd.targets.test-renew-httpd = {
wants = [ "acme-c.example.test.service" ];
after = [ "acme-c.example.test.service" "httpd-config-reload.service" ];
};
};
# Validation via DNS-01 challenge
specialisation.dns-01.configuration = { pkgs, config, nodes, ... }: {
security.acme.certs."example.test" = {
domain = "*.example.test";
group = config.services.nginx.group;
dnsProvider = "exec";
dnsPropagationCheck = false;
credentialsFile = pkgs.writeText "wildcard.env" ''
EXEC_PATH=${dnsScript { inherit pkgs nodes; }}
'';
};
services.nginx.virtualHosts."dns.example.test" = (vhostBase pkgs) // {
useACMEHost = "example.test";
};
};
# Validate service relationships by adding a slow start service to nginx' wants.
# Reproducer for https://github.com/NixOS/nixpkgs/issues/81842
specialisation.slow-startup.configuration = { pkgs, config, nodes, lib, ... }: {
systemd.services.my-slow-service = {
wantedBy = [ "multi-user.target" "nginx.service" ];
before = [ "nginx.service" ];
preStart = "sleep 5";
script = "${pkgs.python3}/bin/python -m http.server";
};
services.nginx.virtualHosts."slow.example.com" = {
forceSSL = true;
enableACME = true;
locations."/".proxyPass = "http://localhost:8000";
};
};
};
# The client will be used to curl the webserver to validate configuration
client = {nodes, lib, pkgs, ...}: {
imports = [ commonConfig ];
networking.nameservers = lib.mkForce [ (dnsServerIP nodes) ];
# OpenSSL will be used for more thorough certificate validation
environment.systemPackages = [ pkgs.openssl ];
};
};
testScript = {nodes, ...}:
let
caDomain = nodes.acme.config.test-support.acme.caDomain;
newServerSystem = nodes.webserver.config.system.build.toplevel;
switchToNewServer = "${newServerSystem}/bin/switch-to-configuration test";
in
# Note, wait_for_unit does not work for oneshot services that do not have RemainAfterExit=true,
# this is because a oneshot goes from inactive => activating => inactive, and never
# reaches the active state. Targets do not have this issue.
''
import time
has_switched = False
def switch_to(node, name):
global has_switched
if has_switched:
node.succeed(
"${switchToNewServer}"
)
has_switched = True
node.succeed(
f"/run/current-system/specialisation/{name}/bin/switch-to-configuration test"
)
# Ensures the issuer of our cert matches the chain
# and matches the issuer we expect it to be.
# It's a good validation to ensure the cert.pem and fullchain.pem
# are not still selfsigned afer verification
def check_issuer(node, cert_name, issuer):
for fname in ("cert.pem", "fullchain.pem"):
actual_issuer = node.succeed(
f"openssl x509 -noout -issuer -in /var/lib/acme/{cert_name}/{fname}"
).partition("=")[2]
print(f"{fname} issuer: {actual_issuer}")
assert issuer.lower() in actual_issuer.lower()
# Ensure cert comes before chain in fullchain.pem
def check_fullchain(node, cert_name):
subject_data = node.succeed(
f"openssl crl2pkcs7 -nocrl -certfile /var/lib/acme/{cert_name}/fullchain.pem"
" | openssl pkcs7 -print_certs -noout"
)
for line in subject_data.lower().split("\n"):
if "subject" in line:
print(f"First subject in fullchain.pem: {line}")
assert cert_name.lower() in line
return
assert False
def check_connection(node, domain, retries=3):
assert retries >= 0, f"Failed to connect to https://{domain}"
result = node.succeed(
"openssl s_client -brief -verify 2 -CAfile /tmp/ca.crt"
f" -servername {domain} -connect {domain}:443 < /dev/null 2>&1"
)
for line in result.lower().split("\n"):
if "verification" in line and "error" in line:
time.sleep(3)
return check_connection(node, domain, retries - 1)
def check_connection_key_bits(node, domain, bits, retries=3):
assert retries >= 0, f"Did not find expected number of bits ({bits}) in key"
result = node.succeed(
"openssl s_client -CAfile /tmp/ca.crt"
f" -servername {domain} -connect {domain}:443 < /dev/null"
" | openssl x509 -noout -text | grep -i Public-Key"
)
print("Key type:", result)
if bits not in result:
time.sleep(3)
return check_connection_key_bits(node, domain, bits, retries - 1)
def check_stapling(node, domain, retries=3):
assert retries >= 0, "OCSP Stapling check failed"
# Pebble doesn't provide a full OCSP responder, so just check the URL
result = node.succeed(
"openssl s_client -CAfile /tmp/ca.crt"
f" -servername {domain} -connect {domain}:443 < /dev/null"
" | openssl x509 -noout -ocsp_uri"
)
print("OCSP Responder URL:", result)
if "${caDomain}:4002" not in result.lower():
time.sleep(3)
return check_stapling(node, domain, retries - 1)
def download_ca_certs(node, retries=5):
assert retries >= 0, "Failed to connect to pebble to download root CA certs"
exit_code, _ = node.execute("curl https://${caDomain}:15000/roots/0 > /tmp/ca.crt")
exit_code_2, _ = node.execute(
"curl https://${caDomain}:15000/intermediate-keys/0 >> /tmp/ca.crt"
)
if exit_code + exit_code_2 > 0:
time.sleep(3)
return download_ca_certs(node, retries - 1)
client.start()
dnsserver.start()
dnsserver.wait_for_unit("pebble-challtestsrv.service")
client.wait_for_unit("default.target")
client.succeed(
'curl --data \'{"host": "${caDomain}", "addresses": ["${nodes.acme.config.networking.primaryIPAddress}"]}\' http://${dnsServerIP nodes}:8055/add-a'
)
acme.start()
webserver.start()
acme.wait_for_unit("network-online.target")
acme.wait_for_unit("pebble.service")
download_ca_certs(client)
with subtest("Can request certificate with HTTPS-01 challenge"):
webserver.wait_for_unit("acme-finished-a.example.test.target")
with subtest("Certificates and accounts have safe + valid permissions"):
group = "${nodes.webserver.config.security.acme.certs."a.example.test".group}"
webserver.succeed(
f"test $(stat -L -c '%a %U %G' /var/lib/acme/a.example.test/*.pem | tee /dev/stderr | grep '640 acme {group}' | wc -l) -eq 5"
)
webserver.succeed(
f"test $(stat -L -c '%a %U %G' /var/lib/acme/.lego/a.example.test/**/a.example.test* | tee /dev/stderr | grep '600 acme {group}' | wc -l) -eq 4"
)
webserver.succeed(
f"test $(stat -L -c '%a %U %G' /var/lib/acme/a.example.test | tee /dev/stderr | grep '750 acme {group}' | wc -l) -eq 1"
)
webserver.succeed(
f"test $(find /var/lib/acme/accounts -type f -exec stat -L -c '%a %U %G' {{}} \\; | tee /dev/stderr | grep -v '600 acme {group}' | wc -l) -eq 0"
)
with subtest("Certs are accepted by web server"):
webserver.succeed("systemctl start nginx.service")
check_fullchain(webserver, "a.example.test")
check_issuer(webserver, "a.example.test", "pebble")
check_connection(client, "a.example.test")
# Selfsigned certs tests happen late so we aren't fighting the system init triggering cert renewal
with subtest("Can generate valid selfsigned certs"):
webserver.succeed("systemctl clean acme-a.example.test.service --what=state")
webserver.succeed("systemctl start acme-selfsigned-a.example.test.service")
check_fullchain(webserver, "a.example.test")
check_issuer(webserver, "a.example.test", "minica")
# Check selfsigned permissions
webserver.succeed(
f"test $(stat -L -c '%a %U %G' /var/lib/acme/a.example.test/*.pem | tee /dev/stderr | grep '640 acme {group}' | wc -l) -eq 5"
)
# Will succeed if nginx can load the certs
webserver.succeed("systemctl start nginx-config-reload.service")
with subtest("Can reload nginx when timer triggers renewal"):
webserver.succeed("systemctl start test-renew-nginx.target")
check_issuer(webserver, "a.example.test", "pebble")
check_connection(client, "a.example.test")
with subtest("Runs 1 cert for account creation before others"):
switch_to(webserver, "account-creation")
webserver.wait_for_unit("acme-finished-a.example.test.target")
check_connection(client, "a.example.test")
webserver.wait_for_unit("acme-finished-b.example.test.target")
webserver.wait_for_unit("acme-finished-c.example.test.target")
check_connection(client, "b.example.test")
check_connection(client, "c.example.test")
with subtest("Can reload web server when cert configuration changes"):
switch_to(webserver, "cert-change")
webserver.wait_for_unit("acme-finished-a.example.test.target")
check_connection_key_bits(client, "a.example.test", "384")
webserver.succeed("grep testing /var/lib/acme/a.example.test/test")
# Clean to remove the testing file (and anything else messy we did)
webserver.succeed("systemctl clean acme-a.example.test.service --what=state")
with subtest("Correctly implements OCSP stapling"):
switch_to(webserver, "ocsp-stapling")
webserver.wait_for_unit("acme-finished-a.example.test.target")
check_stapling(client, "a.example.test")
with subtest("Can request certificate with HTTPS-01 when nginx startup is delayed"):
switch_to(webserver, "slow-startup")
webserver.wait_for_unit("acme-finished-slow.example.com.target")
check_issuer(webserver, "slow.example.com", "pebble")
check_connection(client, "slow.example.com")
with subtest("Can request certificate for vhost + aliases (nginx)"):
# Check the key hash before and after adding an alias. It should not change.
# The previous test reverts the ed384 change
webserver.wait_for_unit("acme-finished-a.example.test.target")
switch_to(webserver, "nginx-aliases")
webserver.wait_for_unit("acme-finished-a.example.test.target")
check_issuer(webserver, "a.example.test", "pebble")
check_connection(client, "a.example.test")
check_connection(client, "b.example.test")
with subtest("Can request certificates for vhost + aliases (apache-httpd)"):
try:
switch_to(webserver, "httpd-aliases")
webserver.wait_for_unit("acme-finished-c.example.test.target")
except Exception as err:
_, output = webserver.execute(
"cat /var/log/httpd/*.log && ls -al /var/lib/acme/acme-challenge"
)
print(output)
raise err
check_issuer(webserver, "c.example.test", "pebble")
check_connection(client, "c.example.test")
check_connection(client, "d.example.test")
with subtest("Can reload httpd when timer triggers renewal"):
# Switch to selfsigned first
webserver.succeed("systemctl clean acme-c.example.test.service --what=state")
webserver.succeed("systemctl start acme-selfsigned-c.example.test.service")
check_issuer(webserver, "c.example.test", "minica")
webserver.succeed("systemctl start httpd-config-reload.service")
webserver.succeed("systemctl start test-renew-httpd.target")
check_issuer(webserver, "c.example.test", "pebble")
check_connection(client, "c.example.test")
with subtest("Can request wildcard certificates using DNS-01 challenge"):
switch_to(webserver, "dns-01")
webserver.wait_for_unit("acme-finished-example.test.target")
check_issuer(webserver, "example.test", "pebble")
check_connection(client, "dns.example.test")
'';
})