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pq_map/discover/
ctdb.rs

1use std::collections::BTreeMap;
2use std::time::Duration;
3
4use tokio_postgres::{Client, NoTls, SimpleQueryMessage};
5
6use crate::config::Config;
7use crate::model::ChainEntry;
8
9#[derive(Debug, Clone)]
10pub struct DbRow {
11    pub cert_id: i64,
12    pub serial: String,
13    pub dns_name: Option<String>,
14    pub common_name: Option<String>,
15    pub not_before: Option<String>,
16    pub not_after: Option<String>,
17    pub key_algorithm: Option<String>,
18    pub key_size: Option<i64>,
19    pub sig_key_algorithm: Option<String>,
20    pub sig_hash_algorithm: Option<String>,
21    pub issuer_ca_name: Option<String>,
22}
23
24const CT_SQL_TEMPLATE: &str = "
25WITH matching AS (
26    SELECT c.id, c.issuer_ca_id, c.certificate
27    FROM certificate c
28    WHERE identities(c.certificate) @@ plainto_tsquery('certwatch', '{domain}')
29      AND x509_notAfter(c.certificate) >= now()
30)
31SELECT
32    m.id,
33    encode(x509_serialnumber(m.certificate), 'hex'),
34    n.name_value,
35    x509_commonName(m.certificate),
36    x509_notBefore(m.certificate)::text,
37    x509_notAfter(m.certificate)::text,
38    x509_keyAlgorithm(m.certificate),
39    x509_keySize(m.certificate),
40    x509_signatureKeyAlgorithm(m.certificate),
41    x509_signatureHashAlgorithm(m.certificate),
42    ca.name
43FROM matching m
44LEFT JOIN ca ON ca.id = m.issuer_ca_id
45CROSS JOIN LATERAL (
46    SELECT encode(raw_value, 'escape') AS name_value, 2 AS src
47    FROM x509_altNames_raw(m.certificate)
48    WHERE type_num = 2
49    UNION ALL
50    SELECT x509_commonName(m.certificate), 1
51) n
52WHERE lower(n.name_value) = lower('{domain}')
53   OR lower(n.name_value) LIKE '%.{domain}'";
54
55pub fn ct_sql(domain: &str) -> Result<String, String> {
56    let domain = domain.to_ascii_lowercase();
57    if domain.is_empty() || domain.len() > 253 {
58        return Err(format!("invalid domain: {domain}"));
59    }
60    if !domain
61        .chars()
62        .all(|c| c.is_ascii_alphanumeric() || c == '.' || c == '-')
63    {
64        return Err(format!("invalid characters in domain: {domain}"));
65    }
66    Ok(CT_SQL_TEMPLATE.replace("{domain}", &domain))
67}
68
69/// A reused certwatch DB connection for the whole CT fetch.
70///
71/// Connecting to crt.sh is expensive, so the snapshot query and the chain
72/// query share one connection, opened lazily on first use. A query that
73/// fails or times out (no response) may still be running server-side, which
74/// poisons the connection: it is hung up, and only the failed query is
75/// re-executed on a fresh one.
76pub struct Session {
77    conninfo: String,
78    client: Option<Client>,
79    drive: Option<tokio::task::JoinHandle<()>>,
80}
81
82impl Session {
83    pub fn new(cfg: &Config) -> Self {
84        Self {
85            conninfo: format!(
86                "host={} port={} user={} dbname={}",
87                cfg.db_host, cfg.db_port, cfg.db_user, cfg.db_name
88            ),
89            client: None,
90            drive: None,
91        }
92    }
93
94    pub async fn fetch_rows(&mut self, domain: &str, cfg: &Config) -> Result<Vec<DbRow>, String> {
95        let mut last_error = String::from("not attempted");
96        for attempt in 1..=cfg.retries {
97            eprintln!(
98                "CT: querying certwatch DB at {}:{} (attempt {attempt}/{})",
99                cfg.db_host, cfg.db_port, cfg.retries
100            );
101            match self.fetch_once(domain, cfg).await {
102                Ok(rows) => return Ok(rows),
103                Err(e) => {
104                    last_error = e;
105                    if attempt < cfg.retries {
106                        let delay = db_backoff_secs(attempt, cfg.retry_delay);
107                        eprintln!(
108                            "CT: {last_error}; re-running this query in {delay}s \
109                             (attempt {attempt}/{} failed)",
110                            cfg.retries
111                        );
112                        tokio::time::sleep(Duration::from_secs(delay)).await;
113                    }
114                }
115            }
116        }
117        eprintln!(
118            "CT: certwatch DB unreachable after {} attempts",
119            cfg.retries
120        );
121        Err(last_error)
122    }
123
124    async fn fetch_once(&mut self, domain: &str, cfg: &Config) -> Result<Vec<DbRow>, String> {
125        let client = self.ensure_connected(cfg).await?;
126        let sql = ct_sql(domain)?;
127        let result = {
128            let query = client.simple_query(&sql);
129            tokio::time::timeout(Duration::from_secs(cfg.db_query_timeout), query).await
130        };
131        match result {
132            Ok(Ok(messages)) => parse_db_rows(&messages),
133            Ok(Err(e)) => {
134                self.hang_up();
135                Err(db_err(e))
136            }
137            Err(_) => {
138                self.hang_up();
139                Err("query timeout (no response)".to_string())
140            }
141        }
142    }
143
144    pub async fn chain_rows(
145        &mut self,
146        ct_ids: &[u64],
147        cfg: &Config,
148    ) -> Result<BTreeMap<u64, Vec<ChainEntry>>, String> {
149        if ct_ids.is_empty() {
150            return Ok(BTreeMap::new());
151        }
152        let mut last_error = String::from("not attempted");
153        for attempt in 1..=cfg.retries {
154            eprintln!(
155                "CT: querying certificate chains at {}:{} (attempt {attempt}/{})",
156                cfg.db_host, cfg.db_port, cfg.retries
157            );
158            match self.chain_once(ct_ids, cfg).await {
159                Ok(chains) => return Ok(chains),
160                Err(e) => {
161                    last_error = e;
162                    if attempt < cfg.retries {
163                        let delay = db_backoff_secs(attempt, cfg.retry_delay);
164                        eprintln!(
165                            "CT: {last_error}; re-running this query in {delay}s \
166                             (attempt {attempt}/{} failed)",
167                            cfg.retries
168                        );
169                        tokio::time::sleep(Duration::from_secs(delay)).await;
170                    }
171                }
172            }
173        }
174        eprintln!("CT: chain query failed after {} attempts", cfg.retries);
175        Err(last_error)
176    }
177
178    async fn chain_once(
179        &mut self,
180        ct_ids: &[u64],
181        cfg: &Config,
182    ) -> Result<BTreeMap<u64, Vec<ChainEntry>>, String> {
183        let client = self.ensure_connected(cfg).await?;
184        let sql = chain_sql(ct_ids);
185        let result = {
186            let query = client.simple_query(&sql);
187            tokio::time::timeout(Duration::from_secs(cfg.db_query_timeout), query).await
188        };
189        match result {
190            Ok(Ok(messages)) => parse_chain_rows(&messages),
191            Ok(Err(e)) => {
192                self.hang_up();
193                Err(db_err(e))
194            }
195            Err(_) => {
196                self.hang_up();
197                Err("query timeout (no response)".to_string())
198            }
199        }
200    }
201
202    async fn ensure_connected(&mut self, cfg: &Config) -> Result<&Client, String> {
203        if self.client.is_none() {
204            eprintln!(
205                "CT: connecting to certwatch DB at {}:{}",
206                cfg.db_host, cfg.db_port
207            );
208            let connect = tokio_postgres::connect(&self.conninfo, NoTls);
209            let (client, connection) =
210                tokio::time::timeout(Duration::from_secs(cfg.db_connect_timeout), connect)
211                    .await
212                    .map_err(|_| "connect timeout".to_string())?
213                    .map_err(db_err)?;
214            self.drive = Some(tokio::spawn(async move {
215                if let Err(e) = connection.await {
216                    eprintln!("CT: db connection dropped: {}", db_err(e));
217                }
218            }));
219            self.client = Some(client);
220        }
221        Ok(self.client.as_ref().unwrap())
222    }
223
224    fn hang_up(&mut self) {
225        if let Some(drive) = self.drive.take() {
226            drive.abort();
227        }
228        self.client = None;
229    }
230}
231
232impl Drop for Session {
233    fn drop(&mut self) {
234        self.hang_up();
235    }
236}
237
238pub fn db_backoff_secs(attempt: u32, retry_delay: u64) -> u64 {
239    retry_delay
240        .saturating_mul(1u64 << (attempt + 1).min(6))
241        .min(60)
242}
243
244const CHAIN_SQL_TEMPLATE: &str = "
245WITH RECURSIVE cert_chain AS (
246    SELECT
247        c.id                  AS certificate_id,
248        c.issuer_ca_id,
249        c.certificate,
250        c.id                  AS leaf_id,
251        0                     AS depth,
252        ARRAY[c.id]::bigint[] AS path
253    FROM certificate c
254    WHERE c.id = ANY(ARRAY[{ids}]::bigint[])
255      AND x509_notBefore(c.certificate) <= now()
256      AND x509_notAfter(c.certificate) >= now()
257
258    UNION ALL
259
260    SELECT
261        parent.id,
262        parent.issuer_ca_id,
263        parent.certificate,
264        cc.leaf_id,
265        cc.depth + 1,
266        cc.path || parent.id
267    FROM cert_chain cc
268
269    JOIN LATERAL (
270        SELECT c2.*
271        FROM ca_certificate cac
272        JOIN certificate c2
273          ON c2.id = cac.certificate_id
274
275        WHERE cac.ca_id = cc.issuer_ca_id
276          AND x509_notBefore(c2.certificate) <= now()
277          AND x509_notAfter(c2.certificate) >= now()
278          AND NOT c2.id = ANY(cc.path)
279
280          AND (
281              x509_authorityKeyId(cc.certificate) IS NULL
282              OR x509_subjectKeyIdentifier(c2.certificate)
283                   = x509_authorityKeyId(cc.certificate)
284          )
285
286        ORDER BY
287            CASE
288                WHEN EXISTS (
289                    SELECT 1
290                    FROM ca_certificate self_ca
291                    WHERE self_ca.certificate_id = c2.id
292                      AND self_ca.ca_id = c2.issuer_ca_id
293                )
294                THEN 0
295                ELSE 1
296            END,
297            x509_notBefore(c2.certificate) DESC,
298            x509_notAfter(c2.certificate) DESC,
299            c2.id DESC
300
301        LIMIT 1
302    ) parent ON true
303
304    WHERE cc.depth < 6
305
306      AND NOT EXISTS (
307          SELECT 1
308          FROM ca_certificate self_ca
309          WHERE self_ca.certificate_id = cc.certificate_id
310            AND self_ca.ca_id = cc.issuer_ca_id
311      )
312)
313
314SELECT
315    cc.leaf_id,
316    cc.depth,
317    cc.certificate_id,
318    cc.issuer_ca_id,
319
320    x509_commonName(cc.certificate) AS common_name,
321
322    encode(
323        x509_subjectKeyIdentifier(cc.certificate),
324        'hex'
325    ) AS ski,
326
327    encode(
328        x509_authorityKeyId(cc.certificate),
329        'hex'
330    ) AS aki,
331
332    x509_notBefore(cc.certificate)::text AS not_before,
333    x509_notAfter(cc.certificate)::text AS not_after,
334
335    x509_keyAlgorithm(cc.certificate) AS key_algorithm,
336    x509_keySize(cc.certificate) AS key_size,
337
338    x509_signatureKeyAlgorithm(cc.certificate)
339        AS signature_key_algorithm,
340
341    x509_signatureHashAlgorithm(cc.certificate)
342        AS signature_hash_algorithm,
343
344    issuer_ca.name AS issuer_ca_name
345
346FROM cert_chain cc
347
348LEFT JOIN ca issuer_ca
349  ON issuer_ca.id = cc.issuer_ca_id
350
351ORDER BY
352    cc.leaf_id,
353    cc.depth";
354
355fn chain_sql(ct_ids: &[u64]) -> String {
356    let ids = ct_ids
357        .iter()
358        .map(|id| id.to_string())
359        .collect::<Vec<_>>()
360        .join(",");
361    CHAIN_SQL_TEMPLATE.replace("{ids}", &ids)
362}
363
364fn parse_chain_row(r: &tokio_postgres::SimpleQueryRow) -> Result<(u64, ChainEntry), String> {
365    let leaf_id: u64 = r
366        .get(0)
367        .ok_or("missing leaf id")?
368        .parse()
369        .map_err(|_| "bad leaf id")?;
370    let entry = ChainEntry {
371        depth: r
372            .get(1)
373            .ok_or("missing depth")?
374            .parse()
375            .map_err(|_| "bad depth")?,
376        certificate_id: r
377            .get(2)
378            .ok_or("missing cert id")?
379            .parse()
380            .map_err(|_| "bad cert id")?,
381        common_name: r.get(4).map(str::to_string),
382        ski: r.get(5).map(str::to_string),
383        aki: r.get(6).map(str::to_string),
384        not_before: r.get(7).and_then(crate::discover::ct::ctdate),
385        not_after: r.get(8).and_then(crate::discover::ct::ctdate),
386        key_algorithm: r.get(9).map(str::to_string),
387        key_size: r.get(10).and_then(|v| v.parse().ok()),
388        signature_key_algorithm: r.get(11).map(str::to_string),
389        signature_hash_algorithm: r.get(12).map(str::to_string),
390        issuer_ca_name: r.get(13).map(str::to_string),
391    };
392    Ok((leaf_id, entry))
393}
394
395fn parse_db_rows(messages: &[SimpleQueryMessage]) -> Result<Vec<DbRow>, String> {
396    messages
397        .iter()
398        .filter_map(|m| match m {
399            SimpleQueryMessage::Row(r) => Some(r),
400            _ => None,
401        })
402        .map(|r| {
403            Ok(DbRow {
404                cert_id: r
405                    .get(0)
406                    .ok_or("missing cert id")?
407                    .parse()
408                    .map_err(|_| "bad cert id")?,
409                serial: r.get(1).ok_or("missing serial")?.to_string(),
410                dns_name: r.get(2).map(str::to_string),
411                common_name: r.get(3).map(str::to_string),
412                not_before: r.get(4).map(str::to_string),
413                not_after: r.get(5).map(str::to_string),
414                key_algorithm: r.get(6).map(str::to_string),
415                key_size: r.get(7).and_then(|v| v.parse().ok()),
416                sig_key_algorithm: r.get(8).map(str::to_string),
417                sig_hash_algorithm: r.get(9).map(str::to_string),
418                issuer_ca_name: r.get(10).map(str::to_string),
419            })
420        })
421        .collect()
422}
423
424fn parse_chain_rows(
425    messages: &[SimpleQueryMessage],
426) -> Result<BTreeMap<u64, Vec<ChainEntry>>, String> {
427    let mut chains: BTreeMap<u64, Vec<ChainEntry>> = BTreeMap::new();
428    for m in messages {
429        if let SimpleQueryMessage::Row(r) = m {
430            let (leaf_id, entry) = parse_chain_row(r)?;
431            chains.entry(leaf_id).or_default().push(entry);
432        }
433    }
434    Ok(chains)
435}
436
437fn db_err(e: tokio_postgres::Error) -> String {
438    if let Some(db) = e.as_db_error() {
439        let mut s = format!("db error {:?}: {}", db.code(), db.message());
440        if let Some(detail) = db.detail() {
441            s.push_str(&format!(" ({detail})"));
442        }
443        return s;
444    }
445    format!("db error: {e}")
446}
447
448#[cfg(test)]
449mod tests {
450    use super::*;
451
452    #[test]
453    fn db_backoff_starts_at_2_cubed_and_caps() {
454        assert_eq!(db_backoff_secs(1, 2), 8);
455        assert_eq!(db_backoff_secs(2, 2), 16);
456        assert_eq!(db_backoff_secs(3, 2), 32);
457        assert_eq!(db_backoff_secs(4, 2), 60, "capped at 60s");
458        assert_eq!(db_backoff_secs(5, 2), 60);
459        assert_eq!(db_backoff_secs(1, 120), 60);
460    }
461}