1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
|
use std::collections::{HashMap, HashSet};
use std::sync::{Arc, RwLock};
use std::time::{Duration, Instant};
use anyhow::Result;
use chrono::Utc;
use futures::{FutureExt, TryFutureExt};
use tokio::select;
use tokio::sync::{mpsc, watch};
use tokio::task::block_in_place;
use tracing::*;
use acme_micro::create_p384_key;
use acme_micro::{Directory, DirectoryUrl};
use rustls::sign::CertifiedKey;
use crate::cert::{Cert, CertSer};
use crate::consul::{self, Consul};
use crate::proxy_config::*;
pub struct CertStore {
consul: Consul,
node_name: String,
letsencrypt_email: String,
certs: RwLock<HashMap<String, Arc<Cert>>>,
self_signed_certs: RwLock<HashMap<String, Arc<Cert>>>,
rx_proxy_config: watch::Receiver<Arc<ProxyConfig>>,
tx_need_cert: mpsc::UnboundedSender<String>,
}
impl CertStore {
pub fn new(
consul: Consul,
node_name: String,
rx_proxy_config: watch::Receiver<Arc<ProxyConfig>>,
letsencrypt_email: String,
exit_on_err: impl Fn(anyhow::Error) + Send + 'static,
) -> Arc<Self> {
let (tx, rx) = mpsc::unbounded_channel();
let cert_store = Arc::new(Self {
consul,
node_name,
certs: RwLock::new(HashMap::new()),
self_signed_certs: RwLock::new(HashMap::new()),
rx_proxy_config,
letsencrypt_email,
tx_need_cert: tx,
});
tokio::spawn(
cert_store
.clone()
.certificate_loop(rx)
.map_err(exit_on_err)
.then(|_| async { info!("Certificate renewal task exited") }),
);
cert_store
}
async fn certificate_loop(
self: Arc<Self>,
mut rx_need_cert: mpsc::UnboundedReceiver<String>,
) -> Result<()> {
let mut rx_proxy_config = self.rx_proxy_config.clone();
let mut t_last_check: HashMap<String, Instant> = HashMap::new();
loop {
let mut domains: HashSet<String> = HashSet::new();
select! {
res = rx_proxy_config.changed() => {
if res.is_err() {
bail!("rx_proxy_config closed");
}
let proxy_config: Arc<ProxyConfig> = rx_proxy_config.borrow().clone();
for ent in proxy_config.entries.iter() {
if let HostDescription::Hostname(domain) = &ent.url_prefix.host {
if let Some((host, _port)) = domain.split_once(':') {
domains.insert(host.to_string());
} else {
domains.insert(domain.clone());
}
}
}
}
need_cert = rx_need_cert.recv() => {
match need_cert {
Some(dom) => {
domains.insert(dom);
while let Ok(dom2) = rx_need_cert.try_recv() {
domains.insert(dom2);
}
}
None => bail!("rx_need_cert closed"),
};
}
}
for dom in domains.iter() {
match t_last_check.get(dom) {
Some(t) if Instant::now() - *t < Duration::from_secs(60) => continue,
_ => t_last_check.insert(dom.to_string(), Instant::now()),
};
debug!("Checking cert for domain: {}", dom);
if let Err(e) = self.check_cert(dom).await {
warn!("({}) Could not get certificate: {}", dom, e);
}
}
}
}
fn get_cert_for_https(self: &Arc<Self>, domain: &str) -> Result<Arc<Cert>> {
// Check if domain is authorized
if !self
.rx_proxy_config
.borrow()
.entries
.iter()
.any(|ent| ent.url_prefix.host.matches(domain))
{
bail!("Domain {} should not have a TLS certificate.", domain);
}
// Check in local memory if it exists
if let Some(cert) = self.certs.read().unwrap().get(domain) {
if cert.is_old() {
self.tx_need_cert.send(domain.to_string())?;
}
return Ok(cert.clone());
}
// Not found in local memory, try to get it in background
self.tx_need_cert.send(domain.to_string())?;
// In the meantime, use a self-signed certificate
if let Some(cert) = self.self_signed_certs.read().unwrap().get(domain) {
return Ok(cert.clone());
}
self.gen_self_signed_certificate(domain)
}
pub async fn warmup_memory_store(self: &Arc<Self>) -> Result<()> {
let consul_certs = self
.consul
.kv_get_prefix("certs/", None)
.await?
.into_inner();
trace!(
"Fetched {} certificate entries from Consul",
consul_certs.len()
);
let mut loaded_certs: usize = 0;
for (domain, cert) in consul_certs {
let certser: CertSer = match serde_json::from_slice(&cert) {
Ok(cs) => cs,
Err(e) => {
warn!("Could not deserialize CertSer for {domain}: {e}");
continue;
}
};
let cert = match Cert::new(certser) {
Ok(c) => c,
Err(e) => {
warn!("Could not create Cert from CertSer for domain {domain}: {e}");
continue;
}
};
self.certs
.write()
.unwrap()
.insert(domain.to_string(), Arc::new(cert));
debug!("({domain}) Certificate loaded from Consul to the Memory Store");
loaded_certs += 1;
}
info!("Memory store warmed up with {loaded_certs} certificates");
Ok(())
}
pub async fn check_cert(self: &Arc<Self>, domain: &str) -> Result<()> {
// First, try locally.
{
let certs = self.certs.read().unwrap();
if let Some(cert) = certs.get(domain) {
if !cert.is_old() {
return Ok(());
}
}
}
// Second, try from Consul.
if let Some(consul_cert) = self
.consul
.kv_get_json::<CertSer>(&format!("certs/{}", domain))
.await?
{
match Cert::new(consul_cert) {
Ok(cert) => {
let cert = Arc::new(cert);
self.certs
.write()
.unwrap()
.insert(domain.to_string(), cert.clone());
debug!("({domain}) Certificate loaded from Consul to the Memory Store");
if !cert.is_old() {
return Ok(());
}
}
Err(e) => {
warn!("Could not create Cert from CertSer for domain {domain}: {e}");
}
};
}
// Third, ask from Let's Encrypt
self.renew_cert(domain).await
}
pub async fn renew_cert(self: &Arc<Self>, domain: &str) -> Result<()> {
info!("({}) Renewing certificate", domain);
// Basic sanity check (we could add more kinds of checks here)
// This is just to help avoid getting rate-limited against ACME server
if !domain.contains('.') || domain.ends_with(".local") {
bail!("Probably not a publicly accessible domain, skipping (a self-signed certificate will be used)");
}
// ---- Acquire lock ----
// the lock is acquired for half an hour,
// so that in case of an error we won't retry before
// that delay expires
let lock_path = format!("renew_lock/{}", domain);
let lock_name = format!("tricot/renew:{}@{}", domain, self.node_name);
let session = self
.consul
.create_session(&consul::locking::SessionRequest {
name: lock_name.clone(),
node: None,
lock_delay: Some("30m".into()),
ttl: Some("45m".into()),
behavior: Some("delete".into()),
})
.await?;
debug!("Lock session: {}", session);
if !self
.consul
.acquire(&lock_path, lock_name.clone().into(), &session)
.await?
{
bail!("Lock is already taken, not renewing for now.");
}
// ---- Accessibility check ----
// We don't want to ask Let's encrypt for a domain that
// is not configured to point here. This can happen with wildcards: someone can send
// a fake SNI to a domain that is not ours. We have to detect it here.
self.check_domain_accessibility(domain, &session).await?;
// ---- Do let's encrypt stuff ----
let dir = Directory::from_url(DirectoryUrl::LetsEncrypt)?;
let contact = vec![format!("mailto:{}", self.letsencrypt_email)];
// Use existing Let's encrypt account or register new one if necessary
let acc = match self.consul.kv_get("letsencrypt_account_key.pem").await? {
Some(acc_privkey) => {
info!("Using existing Let's encrypt account");
dir.load_account(std::str::from_utf8(&acc_privkey)?, contact)?
}
None => {
info!("Creating new Let's encrypt account");
let acc = block_in_place(|| dir.register_account(contact.clone()))?;
self.consul
.kv_put(
"letsencrypt_account_key.pem",
acc.acme_private_key_pem()?.into_bytes().into(),
)
.await?;
acc
}
};
// Order certificate and perform validation
let mut ord_new = acc.new_order(domain, &[])?;
let ord_csr = loop {
if let Some(ord_csr) = ord_new.confirm_validations() {
break ord_csr;
}
let auths = ord_new.authorizations()?;
info!("({}) Creating challenge and storing in Consul", domain);
let chall = auths[0].http_challenge().unwrap();
let chall_key = format!("challenge/{}", chall.http_token());
self.consul
.acquire(&chall_key, chall.http_proof()?.into(), &session)
.await?;
info!("({}) Validating challenge", domain);
block_in_place(|| chall.validate(Duration::from_millis(5000)))?;
info!("({}) Deleting challenge", domain);
self.consul.kv_delete(&chall_key).await?;
block_in_place(|| ord_new.refresh())?;
};
// Generate key and finalize certificate
let pkey_pri = create_p384_key()?;
let ord_cert =
block_in_place(|| ord_csr.finalize_pkey(pkey_pri, Duration::from_millis(5000)))?;
let cert = block_in_place(|| ord_cert.download_cert())?;
info!("({}) Keys and certificate obtained", domain);
let key_pem = cert.private_key().to_string();
let cert_pem = cert.certificate().to_string();
let certser = CertSer {
hostname: domain.to_string(),
date: Utc::now().date_naive(),
valid_days: cert.valid_days_left()?,
key_pem,
cert_pem,
};
let cert = Arc::new(Cert::new(certser.clone())?);
// Store certificate in Consul and local store
self.certs.write().unwrap().insert(domain.to_string(), cert);
self.consul
.kv_put_json(&format!("certs/{}", domain), &certser)
.await?;
// Release locks
self.consul.release(&lock_path, "".into(), &session).await?;
self.consul.kv_delete(&lock_path).await?;
info!("({}) Cert successfully renewed and stored", domain);
Ok(())
}
async fn check_domain_accessibility(&self, domain: &str, session: &str) -> Result<()> {
// Returns Ok(()) only if domain is a correct domain name that
// redirects to this server
let self_challenge_id = uuid::Uuid::new_v4().to_string();
let self_challenge_key = format!("challenge/{}", self_challenge_id);
let self_challenge_resp = uuid::Uuid::new_v4().to_string();
self.consul
.acquire(
&self_challenge_key,
self_challenge_resp.as_bytes().to_vec().into(),
session,
)
.await?;
let httpcli = reqwest::Client::new();
let chall_url = format!(
"http://{}/.well-known/acme-challenge/{}",
domain, self_challenge_id
);
for i in 1..=4 {
tokio::time::sleep(Duration::from_secs(2)).await;
info!("({}) Accessibility check {}/4", domain, i);
let httpresp = httpcli.get(&chall_url).send().await?;
if httpresp.status() == reqwest::StatusCode::OK
&& httpresp.bytes().await? == self_challenge_resp.as_bytes()
{
// Challenge successfully validated
info!("({}) Accessibility check successfull", domain);
return Ok(());
}
tokio::time::sleep(Duration::from_secs(2)).await;
}
bail!("Unable to validate self-challenge for domain accessibility check");
}
fn gen_self_signed_certificate(&self, domain: &str) -> Result<Arc<Cert>> {
let subject_alt_names = vec![domain.to_string(), "localhost".to_string()];
let cert = rcgen::generate_simple_self_signed(subject_alt_names)?;
let certser = CertSer {
hostname: domain.to_string(),
date: Utc::now().date_naive(),
valid_days: 1024,
key_pem: cert.serialize_private_key_pem(),
cert_pem: cert.serialize_pem()?,
};
let cert = Arc::new(Cert::new(certser)?);
self.self_signed_certs
.write()
.unwrap()
.insert(domain.to_string(), cert.clone());
info!("Added self-signed certificate for {}", domain);
Ok(cert)
}
}
pub struct StoreResolver(pub Arc<CertStore>);
impl rustls::server::ResolvesServerCert for StoreResolver {
fn resolve(&self, client_hello: rustls::server::ClientHello<'_>) -> Option<Arc<CertifiedKey>> {
let domain = client_hello.server_name()?;
match self.0.get_cert_for_https(domain) {
Ok(cert) => Some(cert.certkey.clone()),
Err(e) => {
warn!("Could not get certificate for {}: {}", domain, e);
None
}
}
}
}
|