Line data Source code
1 : //! Part of Safekeeper pretending to be Postgres, i.e. handling Postgres
2 : //! protocol commands.
3 :
4 : use anyhow::Context;
5 : use std::str::{self, FromStr};
6 : use std::sync::Arc;
7 : use tokio::io::{AsyncRead, AsyncWrite};
8 : use tracing::{debug, info, info_span, Instrument};
9 :
10 : use crate::auth::check_permission;
11 : use crate::json_ctrl::{handle_json_ctrl, AppendLogicalMessage};
12 :
13 : use crate::metrics::{TrafficMetrics, PG_QUERIES_GAUGE};
14 : use crate::safekeeper::Term;
15 : use crate::timeline::TimelineError;
16 : use crate::wal_service::ConnectionId;
17 : use crate::{GlobalTimelines, SafeKeeperConf};
18 : use postgres_backend::PostgresBackend;
19 : use postgres_backend::QueryError;
20 : use postgres_ffi::PG_TLI;
21 : use pq_proto::{BeMessage, FeStartupPacket, RowDescriptor, INT4_OID, TEXT_OID};
22 : use regex::Regex;
23 : use utils::auth::{Claims, JwtAuth, Scope};
24 : use utils::{
25 : id::{TenantId, TenantTimelineId, TimelineId},
26 : lsn::Lsn,
27 : };
28 :
29 : /// Safekeeper handler of postgres commands
30 : pub struct SafekeeperPostgresHandler {
31 : pub conf: SafeKeeperConf,
32 : /// assigned application name
33 : pub appname: Option<String>,
34 : pub tenant_id: Option<TenantId>,
35 : pub timeline_id: Option<TimelineId>,
36 : pub ttid: TenantTimelineId,
37 : /// Unique connection id is logged in spans for observability.
38 : pub conn_id: ConnectionId,
39 : /// Auth scope allowed on the connections and public key used to check auth tokens. None if auth is not configured.
40 : auth: Option<(Scope, Arc<JwtAuth>)>,
41 : claims: Option<Claims>,
42 : io_metrics: Option<TrafficMetrics>,
43 : }
44 :
45 : /// Parsed Postgres command.
46 : enum SafekeeperPostgresCommand {
47 : StartWalPush,
48 : StartReplication { start_lsn: Lsn, term: Option<Term> },
49 : IdentifySystem,
50 : TimelineStatus,
51 : JSONCtrl { cmd: AppendLogicalMessage },
52 : }
53 :
54 0 : fn parse_cmd(cmd: &str) -> anyhow::Result<SafekeeperPostgresCommand> {
55 0 : if cmd.starts_with("START_WAL_PUSH") {
56 0 : Ok(SafekeeperPostgresCommand::StartWalPush)
57 0 : } else if cmd.starts_with("START_REPLICATION") {
58 0 : let re = Regex::new(
59 0 : // We follow postgres START_REPLICATION LOGICAL options to pass term.
60 0 : r"START_REPLICATION(?: SLOT [^ ]+)?(?: PHYSICAL)? ([[:xdigit:]]+/[[:xdigit:]]+)(?: \(term='(\d+)'\))?",
61 0 : )
62 0 : .unwrap();
63 0 : let caps = re
64 0 : .captures(cmd)
65 0 : .context(format!("failed to parse START_REPLICATION command {}", cmd))?;
66 0 : let start_lsn =
67 0 : Lsn::from_str(&caps[1]).context("parse start LSN from START_REPLICATION command")?;
68 0 : let term = if let Some(m) = caps.get(2) {
69 0 : Some(m.as_str().parse::<u64>().context("invalid term")?)
70 : } else {
71 0 : None
72 : };
73 0 : Ok(SafekeeperPostgresCommand::StartReplication { start_lsn, term })
74 0 : } else if cmd.starts_with("IDENTIFY_SYSTEM") {
75 0 : Ok(SafekeeperPostgresCommand::IdentifySystem)
76 0 : } else if cmd.starts_with("TIMELINE_STATUS") {
77 0 : Ok(SafekeeperPostgresCommand::TimelineStatus)
78 0 : } else if cmd.starts_with("JSON_CTRL") {
79 0 : let cmd = cmd.strip_prefix("JSON_CTRL").context("invalid prefix")?;
80 : Ok(SafekeeperPostgresCommand::JSONCtrl {
81 0 : cmd: serde_json::from_str(cmd)?,
82 : })
83 : } else {
84 0 : anyhow::bail!("unsupported command {cmd}");
85 : }
86 0 : }
87 :
88 0 : fn cmd_to_string(cmd: &SafekeeperPostgresCommand) -> &str {
89 0 : match cmd {
90 0 : SafekeeperPostgresCommand::StartWalPush => "START_WAL_PUSH",
91 0 : SafekeeperPostgresCommand::StartReplication { .. } => "START_REPLICATION",
92 0 : SafekeeperPostgresCommand::TimelineStatus => "TIMELINE_STATUS",
93 0 : SafekeeperPostgresCommand::IdentifySystem => "IDENTIFY_SYSTEM",
94 0 : SafekeeperPostgresCommand::JSONCtrl { .. } => "JSON_CTRL",
95 : }
96 0 : }
97 :
98 : #[async_trait::async_trait]
99 : impl<IO: AsyncRead + AsyncWrite + Unpin + Send> postgres_backend::Handler<IO>
100 : for SafekeeperPostgresHandler
101 : {
102 : // tenant_id and timeline_id are passed in connection string params
103 0 : fn startup(
104 0 : &mut self,
105 0 : _pgb: &mut PostgresBackend<IO>,
106 0 : sm: &FeStartupPacket,
107 0 : ) -> Result<(), QueryError> {
108 0 : if let FeStartupPacket::StartupMessage { params, .. } = sm {
109 0 : if let Some(options) = params.options_raw() {
110 0 : for opt in options {
111 : // FIXME `ztenantid` and `ztimelineid` left for compatibility during deploy,
112 : // remove these after the PR gets deployed:
113 : // https://github.com/neondatabase/neon/pull/2433#discussion_r970005064
114 0 : match opt.split_once('=') {
115 0 : Some(("ztenantid", value)) | Some(("tenant_id", value)) => {
116 0 : self.tenant_id = Some(value.parse().with_context(|| {
117 0 : format!("Failed to parse {value} as tenant id")
118 0 : })?);
119 : }
120 0 : Some(("ztimelineid", value)) | Some(("timeline_id", value)) => {
121 0 : self.timeline_id = Some(value.parse().with_context(|| {
122 0 : format!("Failed to parse {value} as timeline id")
123 0 : })?);
124 : }
125 0 : Some(("availability_zone", client_az)) => {
126 0 : if let Some(metrics) = self.io_metrics.as_ref() {
127 0 : metrics.set_client_az(client_az)
128 0 : }
129 : }
130 0 : _ => continue,
131 : }
132 : }
133 0 : }
134 :
135 0 : if let Some(app_name) = params.get("application_name") {
136 0 : self.appname = Some(app_name.to_owned());
137 0 : if let Some(metrics) = self.io_metrics.as_ref() {
138 0 : metrics.set_app_name(app_name)
139 0 : }
140 0 : }
141 :
142 0 : let ttid = TenantTimelineId::new(
143 0 : self.tenant_id.unwrap_or(TenantId::from([0u8; 16])),
144 0 : self.timeline_id.unwrap_or(TimelineId::from([0u8; 16])),
145 0 : );
146 0 : tracing::Span::current().record("ttid", tracing::field::display(ttid));
147 0 :
148 0 : Ok(())
149 : } else {
150 0 : Err(QueryError::Other(anyhow::anyhow!(
151 0 : "Safekeeper received unexpected initial message: {sm:?}"
152 0 : )))
153 : }
154 0 : }
155 :
156 0 : fn check_auth_jwt(
157 0 : &mut self,
158 0 : _pgb: &mut PostgresBackend<IO>,
159 0 : jwt_response: &[u8],
160 0 : ) -> Result<(), QueryError> {
161 0 : // this unwrap is never triggered, because check_auth_jwt only called when auth_type is NeonJWT
162 0 : // which requires auth to be present
163 0 : let (allowed_auth_scope, auth) = self
164 0 : .auth
165 0 : .as_ref()
166 0 : .expect("auth_type is configured but .auth of handler is missing");
167 0 : let data = auth
168 0 : .decode(str::from_utf8(jwt_response).context("jwt response is not UTF-8")?)
169 0 : .map_err(|e| QueryError::Unauthorized(e.0))?;
170 :
171 : // The handler might be configured to allow only tenant scope tokens.
172 0 : if matches!(allowed_auth_scope, Scope::Tenant)
173 0 : && !matches!(data.claims.scope, Scope::Tenant)
174 : {
175 0 : return Err(QueryError::Unauthorized(
176 0 : "passed JWT token is for full access, but only tenant scope is allowed".into(),
177 0 : ));
178 0 : }
179 :
180 0 : if matches!(data.claims.scope, Scope::Tenant) && data.claims.tenant_id.is_none() {
181 0 : return Err(QueryError::Unauthorized(
182 0 : "jwt token scope is Tenant, but tenant id is missing".into(),
183 0 : ));
184 0 : }
185 0 :
186 0 : debug!(
187 0 : "jwt scope check succeeded for scope: {:#?} by tenant id: {:?}",
188 : data.claims.scope, data.claims.tenant_id,
189 : );
190 :
191 0 : self.claims = Some(data.claims);
192 0 : Ok(())
193 0 : }
194 :
195 0 : async fn process_query(
196 0 : &mut self,
197 0 : pgb: &mut PostgresBackend<IO>,
198 0 : query_string: &str,
199 0 : ) -> Result<(), QueryError> {
200 0 : if query_string
201 0 : .to_ascii_lowercase()
202 0 : .starts_with("set datestyle to ")
203 0 : {
204 0 : // important for debug because psycopg2 executes "SET datestyle TO 'ISO'" on connect
205 0 : pgb.write_message_noflush(&BeMessage::CommandComplete(b"SELECT 1"))?;
206 0 : return Ok(());
207 0 : }
208 0 :
209 0 : let cmd = parse_cmd(query_string)?;
210 0 : let cmd_str = cmd_to_string(&cmd);
211 0 :
212 0 : let _guard = PG_QUERIES_GAUGE.with_label_values(&[cmd_str]).guard();
213 0 :
214 0 : info!("got query {:?}", query_string);
215 0 :
216 0 : let tenant_id = self.tenant_id.context("tenantid is required")?;
217 0 : let timeline_id = self.timeline_id.context("timelineid is required")?;
218 0 : self.check_permission(Some(tenant_id))?;
219 0 : self.ttid = TenantTimelineId::new(tenant_id, timeline_id);
220 0 :
221 0 : match cmd {
222 0 : SafekeeperPostgresCommand::StartWalPush => {
223 0 : self.handle_start_wal_push(pgb)
224 0 : .instrument(info_span!("WAL receiver"))
225 0 : .await
226 0 : }
227 0 : SafekeeperPostgresCommand::StartReplication { start_lsn, term } => {
228 0 : self.handle_start_replication(pgb, start_lsn, term)
229 0 : .instrument(info_span!("WAL sender"))
230 0 : .await
231 0 : }
232 0 : SafekeeperPostgresCommand::IdentifySystem => self.handle_identify_system(pgb).await,
233 0 : SafekeeperPostgresCommand::TimelineStatus => self.handle_timeline_status(pgb).await,
234 0 : SafekeeperPostgresCommand::JSONCtrl { ref cmd } => {
235 0 : handle_json_ctrl(self, pgb, cmd).await
236 0 : }
237 0 : }
238 0 : }
239 : }
240 :
241 : impl SafekeeperPostgresHandler {
242 0 : pub fn new(
243 0 : conf: SafeKeeperConf,
244 0 : conn_id: u32,
245 0 : io_metrics: Option<TrafficMetrics>,
246 0 : auth: Option<(Scope, Arc<JwtAuth>)>,
247 0 : ) -> Self {
248 0 : SafekeeperPostgresHandler {
249 0 : conf,
250 0 : appname: None,
251 0 : tenant_id: None,
252 0 : timeline_id: None,
253 0 : ttid: TenantTimelineId::empty(),
254 0 : conn_id,
255 0 : claims: None,
256 0 : auth,
257 0 : io_metrics,
258 0 : }
259 0 : }
260 :
261 : // when accessing management api supply None as an argument
262 : // when using to authorize tenant pass corresponding tenant id
263 0 : fn check_permission(&self, tenant_id: Option<TenantId>) -> Result<(), QueryError> {
264 0 : if self.auth.is_none() {
265 : // auth is set to Trust, nothing to check so just return ok
266 0 : return Ok(());
267 0 : }
268 0 : // auth is some, just checked above, when auth is some
269 0 : // then claims are always present because of checks during connection init
270 0 : // so this expect won't trigger
271 0 : let claims = self
272 0 : .claims
273 0 : .as_ref()
274 0 : .expect("claims presence already checked");
275 0 : check_permission(claims, tenant_id).map_err(|e| QueryError::Unauthorized(e.0))
276 0 : }
277 :
278 0 : async fn handle_timeline_status<IO: AsyncRead + AsyncWrite + Unpin>(
279 0 : &mut self,
280 0 : pgb: &mut PostgresBackend<IO>,
281 0 : ) -> Result<(), QueryError> {
282 : // Get timeline, handling "not found" error
283 0 : let tli = match GlobalTimelines::get(self.ttid) {
284 0 : Ok(tli) => Ok(Some(tli)),
285 0 : Err(TimelineError::NotFound(_)) => Ok(None),
286 0 : Err(e) => Err(QueryError::Other(e.into())),
287 0 : }?;
288 :
289 : // Write row description
290 0 : pgb.write_message_noflush(&BeMessage::RowDescription(&[
291 0 : RowDescriptor::text_col(b"flush_lsn"),
292 0 : RowDescriptor::text_col(b"commit_lsn"),
293 0 : ]))?;
294 :
295 : // Write row if timeline exists
296 0 : if let Some(tli) = tli {
297 0 : let (inmem, _state) = tli.get_state().await;
298 0 : let flush_lsn = tli.get_flush_lsn().await;
299 0 : let commit_lsn = inmem.commit_lsn;
300 0 : pgb.write_message_noflush(&BeMessage::DataRow(&[
301 0 : Some(flush_lsn.to_string().as_bytes()),
302 0 : Some(commit_lsn.to_string().as_bytes()),
303 0 : ]))?;
304 0 : }
305 :
306 0 : pgb.write_message_noflush(&BeMessage::CommandComplete(b"TIMELINE_STATUS"))?;
307 0 : Ok(())
308 0 : }
309 :
310 : ///
311 : /// Handle IDENTIFY_SYSTEM replication command
312 : ///
313 0 : async fn handle_identify_system<IO: AsyncRead + AsyncWrite + Unpin>(
314 0 : &mut self,
315 0 : pgb: &mut PostgresBackend<IO>,
316 0 : ) -> Result<(), QueryError> {
317 0 : let tli = GlobalTimelines::get(self.ttid).map_err(|e| QueryError::Other(e.into()))?;
318 :
319 0 : let lsn = if self.is_walproposer_recovery() {
320 : // walproposer should get all local WAL until flush_lsn
321 0 : tli.get_flush_lsn().await
322 : } else {
323 : // other clients shouldn't get any uncommitted WAL
324 0 : tli.get_state().await.0.commit_lsn
325 : }
326 0 : .to_string();
327 :
328 0 : let sysid = tli.get_state().await.1.server.system_id.to_string();
329 0 : let lsn_bytes = lsn.as_bytes();
330 0 : let tli = PG_TLI.to_string();
331 0 : let tli_bytes = tli.as_bytes();
332 0 : let sysid_bytes = sysid.as_bytes();
333 0 :
334 0 : pgb.write_message_noflush(&BeMessage::RowDescription(&[
335 0 : RowDescriptor {
336 0 : name: b"systemid",
337 0 : typoid: TEXT_OID,
338 0 : typlen: -1,
339 0 : ..Default::default()
340 0 : },
341 0 : RowDescriptor {
342 0 : name: b"timeline",
343 0 : typoid: INT4_OID,
344 0 : typlen: 4,
345 0 : ..Default::default()
346 0 : },
347 0 : RowDescriptor {
348 0 : name: b"xlogpos",
349 0 : typoid: TEXT_OID,
350 0 : typlen: -1,
351 0 : ..Default::default()
352 0 : },
353 0 : RowDescriptor {
354 0 : name: b"dbname",
355 0 : typoid: TEXT_OID,
356 0 : typlen: -1,
357 0 : ..Default::default()
358 0 : },
359 0 : ]))?
360 0 : .write_message_noflush(&BeMessage::DataRow(&[
361 0 : Some(sysid_bytes),
362 0 : Some(tli_bytes),
363 0 : Some(lsn_bytes),
364 0 : None,
365 0 : ]))?
366 0 : .write_message_noflush(&BeMessage::CommandComplete(b"IDENTIFY_SYSTEM"))?;
367 0 : Ok(())
368 0 : }
369 :
370 : /// Returns true if current connection is a replication connection, originating
371 : /// from a walproposer recovery function. This connection gets a special handling:
372 : /// safekeeper must stream all local WAL till the flush_lsn, whether committed or not.
373 0 : pub fn is_walproposer_recovery(&self) -> bool {
374 0 : match &self.appname {
375 0 : None => false,
376 0 : Some(appname) => {
377 0 : appname == "wal_proposer_recovery" ||
378 : // set by safekeeper peer recovery
379 0 : appname.starts_with("safekeeper")
380 : }
381 : }
382 0 : }
383 : }
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