Line data Source code
1 : //! Postgres protocol messages serialization-deserialization. See
2 : //! <https://www.postgresql.org/docs/devel/protocol-message-formats.html>
3 : //! on message formats.
4 :
5 : pub mod framed;
6 :
7 : use byteorder::{BigEndian, ReadBytesExt};
8 : use bytes::{Buf, BufMut, Bytes, BytesMut};
9 : use std::{borrow::Cow, collections::HashMap, fmt, io, str};
10 :
11 : // re-export for use in utils pageserver_feedback.rs
12 : pub use postgres_protocol::PG_EPOCH;
13 :
14 : pub type Oid = u32;
15 : pub type SystemId = u64;
16 :
17 : pub const INT8_OID: Oid = 20;
18 : pub const INT4_OID: Oid = 23;
19 : pub const TEXT_OID: Oid = 25;
20 :
21 135 : #[derive(Debug)]
22 : pub enum FeMessage {
23 : // Simple query.
24 : Query(Bytes),
25 : // Extended query protocol.
26 : Parse(FeParseMessage),
27 : Describe(FeDescribeMessage),
28 : Bind(FeBindMessage),
29 : Execute(FeExecuteMessage),
30 : Close(FeCloseMessage),
31 : Sync,
32 : Terminate,
33 : CopyData(Bytes),
34 : CopyDone,
35 : CopyFail,
36 : PasswordMessage(Bytes),
37 : }
38 :
39 132 : #[derive(Debug)]
40 : pub enum FeStartupPacket {
41 : CancelRequest(CancelKeyData),
42 : SslRequest,
43 : GssEncRequest,
44 : StartupMessage {
45 : major_version: u32,
46 : minor_version: u32,
47 : params: StartupMessageParams,
48 : },
49 : }
50 :
51 70 : #[derive(Debug)]
52 : pub struct StartupMessageParams {
53 : params: HashMap<String, String>,
54 : }
55 :
56 : impl StartupMessageParams {
57 : /// Get parameter's value by its name.
58 7750 : pub fn get(&self, name: &str) -> Option<&str> {
59 7750 : self.params.get(name).map(|s| s.as_str())
60 7750 : }
61 :
62 : /// Split command-line options according to PostgreSQL's logic,
63 : /// taking into account all escape sequences but leaving them as-is.
64 : /// [`None`] means that there's no `options` in [`Self`].
65 3819 : pub fn options_raw(&self) -> Option<impl Iterator<Item = &str>> {
66 3819 : self.get("options").map(Self::parse_options_raw)
67 3819 : }
68 :
69 : /// Split command-line options according to PostgreSQL's logic,
70 : /// applying all escape sequences (using owned strings as needed).
71 : /// [`None`] means that there's no `options` in [`Self`].
72 5 : pub fn options_escaped(&self) -> Option<impl Iterator<Item = Cow<'_, str>>> {
73 5 : self.get("options").map(Self::parse_options_escaped)
74 5 : }
75 :
76 : /// Split command-line options according to PostgreSQL's logic,
77 : /// taking into account all escape sequences but leaving them as-is.
78 3797 : pub fn parse_options_raw(input: &str) -> impl Iterator<Item = &str> {
79 3797 : // See `postgres: pg_split_opts`.
80 3797 : let mut last_was_escape = false;
81 3797 : input
82 338194 : .split(move |c: char| {
83 : // We split by non-escaped whitespace symbols.
84 338194 : let should_split = c.is_ascii_whitespace() && !last_was_escape;
85 338194 : last_was_escape = c == '\\' && !last_was_escape;
86 338194 : should_split
87 338194 : })
88 11356 : .filter(|s| !s.is_empty())
89 3797 : }
90 :
91 : /// Split command-line options according to PostgreSQL's logic,
92 : /// applying all escape sequences (using owned strings as needed).
93 4 : pub fn parse_options_escaped(input: &str) -> impl Iterator<Item = Cow<'_, str>> {
94 4 : // See `postgres: pg_split_opts`.
95 7 : Self::parse_options_raw(input).map(|s| {
96 7 : let mut preserve_next_escape = false;
97 17 : let escape = |c| {
98 : // We should remove '\\' unless it's preceded by '\\'.
99 17 : let should_remove = c == '\\' && !preserve_next_escape;
100 17 : preserve_next_escape = should_remove;
101 17 : should_remove
102 17 : };
103 :
104 7 : match s.contains('\\') {
105 3 : true => Cow::Owned(s.replace(escape, "")),
106 4 : false => Cow::Borrowed(s),
107 : }
108 7 : })
109 4 : }
110 :
111 : /// Iterate through key-value pairs in an arbitrary order.
112 0 : pub fn iter(&self) -> impl Iterator<Item = (&str, &str)> {
113 0 : self.params.iter().map(|(k, v)| (k.as_str(), v.as_str()))
114 0 : }
115 :
116 : // This function is mostly useful in tests.
117 : #[doc(hidden)]
118 41 : pub fn new<'a, const N: usize>(pairs: [(&'a str, &'a str); N]) -> Self {
119 41 : Self {
120 88 : params: pairs.map(|(k, v)| (k.to_owned(), v.to_owned())).into(),
121 41 : }
122 41 : }
123 : }
124 :
125 92 : #[derive(Debug, Hash, PartialEq, Eq, Clone, Copy)]
126 : pub struct CancelKeyData {
127 : pub backend_pid: i32,
128 : pub cancel_key: i32,
129 : }
130 :
131 : impl fmt::Display for CancelKeyData {
132 124 : fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
133 124 : let hi = (self.backend_pid as u64) << 32;
134 124 : let lo = self.cancel_key as u64;
135 124 : let id = hi | lo;
136 124 :
137 124 : // This format is more compact and might work better for logs.
138 124 : f.debug_tuple("CancelKeyData")
139 124 : .field(&format_args!("{:x}", id))
140 124 : .finish()
141 124 : }
142 : }
143 :
144 : use rand::distributions::{Distribution, Standard};
145 : impl Distribution<CancelKeyData> for Standard {
146 32 : fn sample<R: rand::Rng + ?Sized>(&self, rng: &mut R) -> CancelKeyData {
147 32 : CancelKeyData {
148 32 : backend_pid: rng.gen(),
149 32 : cancel_key: rng.gen(),
150 32 : }
151 32 : }
152 : }
153 :
154 : // We only support the simple case of Parse on unnamed prepared statement and
155 : // no params
156 0 : #[derive(Debug)]
157 : pub struct FeParseMessage {
158 : pub query_string: Bytes,
159 : }
160 :
161 0 : #[derive(Debug)]
162 : pub struct FeDescribeMessage {
163 : pub kind: u8, // 'S' to describe a prepared statement; or 'P' to describe a portal.
164 : // we only support unnamed prepared stmt or portal
165 : }
166 :
167 : // we only support unnamed prepared stmt and portal
168 0 : #[derive(Debug)]
169 : pub struct FeBindMessage;
170 :
171 : // we only support unnamed prepared stmt or portal
172 0 : #[derive(Debug)]
173 : pub struct FeExecuteMessage {
174 : /// max # of rows
175 : pub maxrows: i32,
176 : }
177 :
178 : // we only support unnamed prepared stmt and portal
179 0 : #[derive(Debug)]
180 : pub struct FeCloseMessage;
181 :
182 : /// An error occurred while parsing or serializing raw stream into Postgres
183 : /// messages.
184 0 : #[derive(thiserror::Error, Debug)]
185 : pub enum ProtocolError {
186 : /// Invalid packet was received from the client (e.g. unexpected message
187 : /// type or broken len).
188 : #[error("Protocol error: {0}")]
189 : Protocol(String),
190 : /// Failed to parse or, (unlikely), serialize a protocol message.
191 : #[error("Message parse error: {0}")]
192 : BadMessage(String),
193 : }
194 :
195 : impl ProtocolError {
196 : /// Proxy stream.rs uses only io::Error; provide it.
197 0 : pub fn into_io_error(self) -> io::Error {
198 0 : io::Error::new(io::ErrorKind::Other, self.to_string())
199 0 : }
200 : }
201 :
202 : impl FeMessage {
203 : /// Read and parse one message from the `buf` input buffer. If there is at
204 : /// least one valid message, returns it, advancing `buf`; redundant copies
205 : /// are avoided, as thanks to `bytes` crate ptrs in parsed message point
206 : /// directly into the `buf` (processed data is garbage collected after
207 : /// parsed message is dropped).
208 : ///
209 : /// Returns None if `buf` doesn't contain enough data for a single message.
210 : /// For efficiency, tries to reserve large enough space in `buf` for the
211 : /// next message in this case to save the repeated calls.
212 : ///
213 : /// Returns Error if message is malformed, the only possible ErrorKind is
214 : /// InvalidInput.
215 : //
216 : // Inspired by rust-postgres Message::parse.
217 15417306 : pub fn parse(buf: &mut BytesMut) -> Result<Option<FeMessage>, ProtocolError> {
218 15417306 : // Every message contains message type byte and 4 bytes len; can't do
219 15417306 : // much without them.
220 15417306 : if buf.len() < 5 {
221 7278005 : let to_read = 5 - buf.len();
222 7278005 : buf.reserve(to_read);
223 7278005 : return Ok(None);
224 8139301 : }
225 8139301 :
226 8139301 : // We shouldn't advance `buf` as probably full message is not there yet,
227 8139301 : // so can't directly use Bytes::get_u32 etc.
228 8139301 : let tag = buf[0];
229 8139301 : let len = (&buf[1..5]).read_u32::<BigEndian>().unwrap();
230 8139301 : if len < 4 {
231 0 : return Err(ProtocolError::Protocol(format!(
232 0 : "invalid message length {}",
233 0 : len
234 0 : )));
235 8139301 : }
236 8139301 :
237 8139301 : // length field includes itself, but not message type.
238 8139301 : let total_len = len as usize + 1;
239 8139301 : if buf.len() < total_len {
240 : // Don't have full message yet.
241 111963 : let to_read = total_len - buf.len();
242 111963 : buf.reserve(to_read);
243 111963 : return Ok(None);
244 8027338 : }
245 8027338 :
246 8027338 : // got the message, advance buffer
247 8027338 : let mut msg = buf.split_to(total_len).freeze();
248 8027338 : msg.advance(5); // consume message type and len
249 8027338 :
250 8027338 : match tag {
251 9172 : b'Q' => Ok(Some(FeMessage::Query(msg))),
252 662 : b'P' => Ok(Some(FeParseMessage::parse(msg)?)),
253 662 : b'D' => Ok(Some(FeDescribeMessage::parse(msg)?)),
254 662 : b'E' => Ok(Some(FeExecuteMessage::parse(msg)?)),
255 662 : b'B' => Ok(Some(FeBindMessage::parse(msg)?)),
256 661 : b'C' => Ok(Some(FeCloseMessage::parse(msg)?)),
257 2001 : b'S' => Ok(Some(FeMessage::Sync)),
258 1586 : b'X' => Ok(Some(FeMessage::Terminate)),
259 8010840 : b'd' => Ok(Some(FeMessage::CopyData(msg))),
260 6 : b'c' => Ok(Some(FeMessage::CopyDone)),
261 152 : b'f' => Ok(Some(FeMessage::CopyFail)),
262 272 : b'p' => Ok(Some(FeMessage::PasswordMessage(msg))),
263 0 : tag => Err(ProtocolError::Protocol(format!(
264 0 : "unknown message tag: {tag},'{msg:?}'"
265 0 : ))),
266 : }
267 15417306 : }
268 : }
269 :
270 : impl FeStartupPacket {
271 : /// Read and parse startup message from the `buf` input buffer. It is
272 : /// different from [`FeMessage::parse`] because startup messages don't have
273 : /// message type byte; otherwise, its comments apply.
274 31999 : pub fn parse(buf: &mut BytesMut) -> Result<Option<FeStartupPacket>, ProtocolError> {
275 31999 : const MAX_STARTUP_PACKET_LENGTH: usize = 10000;
276 31999 : const RESERVED_INVALID_MAJOR_VERSION: u32 = 1234;
277 31999 : const CANCEL_REQUEST_CODE: u32 = 5678;
278 31999 : const NEGOTIATE_SSL_CODE: u32 = 5679;
279 31999 : const NEGOTIATE_GSS_CODE: u32 = 5680;
280 31999 :
281 31999 : // need at least 4 bytes with packet len
282 31999 : if buf.len() < 4 {
283 16000 : let to_read = 4 - buf.len();
284 16000 : buf.reserve(to_read);
285 16000 : return Ok(None);
286 15999 : }
287 15999 :
288 15999 : // We shouldn't advance `buf` as probably full message is not there yet,
289 15999 : // so can't directly use Bytes::get_u32 etc.
290 15999 : let len = (&buf[0..4]).read_u32::<BigEndian>().unwrap() as usize;
291 15999 : // The proposed replacement is `!(4..=MAX_STARTUP_PACKET_LENGTH).contains(&len)`
292 15999 : // which is less readable
293 15999 : #[allow(clippy::manual_range_contains)]
294 15999 : if len < 4 || len > MAX_STARTUP_PACKET_LENGTH {
295 0 : return Err(ProtocolError::Protocol(format!(
296 0 : "invalid startup packet message length {}",
297 0 : len
298 0 : )));
299 15999 : }
300 15999 :
301 15999 : if buf.len() < len {
302 : // Don't have full message yet.
303 0 : let to_read = len - buf.len();
304 0 : buf.reserve(to_read);
305 0 : return Ok(None);
306 15999 : }
307 15999 :
308 15999 : // got the message, advance buffer
309 15999 : let mut msg = buf.split_to(len).freeze();
310 15999 : msg.advance(4); // consume len
311 15999 :
312 15999 : let request_code = msg.get_u32();
313 15999 : let req_hi = request_code >> 16;
314 15999 : let req_lo = request_code & ((1 << 16) - 1);
315 : // StartupMessage, CancelRequest, SSLRequest etc are differentiated by request code.
316 15999 : let message = match (req_hi, req_lo) {
317 : (RESERVED_INVALID_MAJOR_VERSION, CANCEL_REQUEST_CODE) => {
318 0 : if msg.remaining() != 8 {
319 0 : return Err(ProtocolError::BadMessage(
320 0 : "CancelRequest message is malformed, backend PID / secret key missing"
321 0 : .to_owned(),
322 0 : ));
323 0 : }
324 0 : FeStartupPacket::CancelRequest(CancelKeyData {
325 0 : backend_pid: msg.get_i32(),
326 0 : cancel_key: msg.get_i32(),
327 0 : })
328 : }
329 : (RESERVED_INVALID_MAJOR_VERSION, NEGOTIATE_SSL_CODE) => {
330 : // Requested upgrade to SSL (aka TLS)
331 6898 : FeStartupPacket::SslRequest
332 : }
333 : (RESERVED_INVALID_MAJOR_VERSION, NEGOTIATE_GSS_CODE) => {
334 : // Requested upgrade to GSSAPI
335 0 : FeStartupPacket::GssEncRequest
336 : }
337 0 : (RESERVED_INVALID_MAJOR_VERSION, unrecognized_code) => {
338 0 : return Err(ProtocolError::Protocol(format!(
339 0 : "Unrecognized request code {unrecognized_code}"
340 0 : )));
341 : }
342 : // TODO bail if protocol major_version is not 3?
343 9101 : (major_version, minor_version) => {
344 : // StartupMessage
345 :
346 : // Parse pairs of null-terminated strings (key, value).
347 : // See `postgres: ProcessStartupPacket, build_startup_packet`.
348 9101 : let mut tokens = str::from_utf8(&msg)
349 9101 : .map_err(|_e| {
350 0 : ProtocolError::BadMessage("StartupMessage params: invalid utf-8".to_owned())
351 9101 : })?
352 9101 : .strip_suffix('\0') // drop packet's own null
353 9101 : .ok_or_else(|| {
354 0 : ProtocolError::Protocol(
355 0 : "StartupMessage params: missing null terminator".to_string(),
356 0 : )
357 9101 : })?
358 9101 : .split_terminator('\0');
359 9101 :
360 9101 : let mut params = HashMap::new();
361 32027 : while let Some(name) = tokens.next() {
362 22926 : let value = tokens.next().ok_or_else(|| {
363 0 : ProtocolError::Protocol(
364 0 : "StartupMessage params: key without value".to_string(),
365 0 : )
366 22926 : })?;
367 :
368 22926 : params.insert(name.to_owned(), value.to_owned());
369 : }
370 :
371 9101 : FeStartupPacket::StartupMessage {
372 9101 : major_version,
373 9101 : minor_version,
374 9101 : params: StartupMessageParams { params },
375 9101 : }
376 : }
377 : };
378 15999 : Ok(Some(message))
379 31999 : }
380 : }
381 :
382 : impl FeParseMessage {
383 662 : fn parse(mut buf: Bytes) -> Result<FeMessage, ProtocolError> {
384 : // FIXME: the rust-postgres driver uses a named prepared statement
385 : // for copy_out(). We're not prepared to handle that correctly. For
386 : // now, just ignore the statement name, assuming that the client never
387 : // uses more than one prepared statement at a time.
388 :
389 662 : let _pstmt_name = read_cstr(&mut buf)?;
390 662 : let query_string = read_cstr(&mut buf)?;
391 662 : if buf.remaining() < 2 {
392 0 : return Err(ProtocolError::BadMessage(
393 0 : "Parse message is malformed, nparams missing".to_string(),
394 0 : ));
395 662 : }
396 662 : let nparams = buf.get_i16();
397 662 :
398 662 : if nparams != 0 {
399 0 : return Err(ProtocolError::BadMessage(
400 0 : "query params not implemented".to_string(),
401 0 : ));
402 662 : }
403 662 :
404 662 : Ok(FeMessage::Parse(FeParseMessage { query_string }))
405 662 : }
406 : }
407 :
408 : impl FeDescribeMessage {
409 662 : fn parse(mut buf: Bytes) -> Result<FeMessage, ProtocolError> {
410 662 : let kind = buf.get_u8();
411 662 : let _pstmt_name = read_cstr(&mut buf)?;
412 :
413 : // FIXME: see FeParseMessage::parse
414 662 : if kind != b'S' {
415 0 : return Err(ProtocolError::BadMessage(
416 0 : "only prepared statemement Describe is implemented".to_string(),
417 0 : ));
418 662 : }
419 662 :
420 662 : Ok(FeMessage::Describe(FeDescribeMessage { kind }))
421 662 : }
422 : }
423 :
424 : impl FeExecuteMessage {
425 662 : fn parse(mut buf: Bytes) -> Result<FeMessage, ProtocolError> {
426 662 : let portal_name = read_cstr(&mut buf)?;
427 662 : if buf.remaining() < 4 {
428 0 : return Err(ProtocolError::BadMessage(
429 0 : "FeExecuteMessage message is malformed, maxrows missing".to_string(),
430 0 : ));
431 662 : }
432 662 : let maxrows = buf.get_i32();
433 662 :
434 662 : if !portal_name.is_empty() {
435 0 : return Err(ProtocolError::BadMessage(
436 0 : "named portals not implemented".to_string(),
437 0 : ));
438 662 : }
439 662 : if maxrows != 0 {
440 0 : return Err(ProtocolError::BadMessage(
441 0 : "row limit in Execute message not implemented".to_string(),
442 0 : ));
443 662 : }
444 662 :
445 662 : Ok(FeMessage::Execute(FeExecuteMessage { maxrows }))
446 662 : }
447 : }
448 :
449 : impl FeBindMessage {
450 662 : fn parse(mut buf: Bytes) -> Result<FeMessage, ProtocolError> {
451 662 : let portal_name = read_cstr(&mut buf)?;
452 662 : let _pstmt_name = read_cstr(&mut buf)?;
453 :
454 : // FIXME: see FeParseMessage::parse
455 662 : if !portal_name.is_empty() {
456 0 : return Err(ProtocolError::BadMessage(
457 0 : "named portals not implemented".to_string(),
458 0 : ));
459 662 : }
460 662 :
461 662 : Ok(FeMessage::Bind(FeBindMessage))
462 662 : }
463 : }
464 :
465 : impl FeCloseMessage {
466 661 : fn parse(mut buf: Bytes) -> Result<FeMessage, ProtocolError> {
467 661 : let _kind = buf.get_u8();
468 661 : let _pstmt_or_portal_name = read_cstr(&mut buf)?;
469 :
470 : // FIXME: we do nothing with Close
471 661 : Ok(FeMessage::Close(FeCloseMessage))
472 661 : }
473 : }
474 :
475 : // Backend
476 :
477 0 : #[derive(Debug)]
478 : pub enum BeMessage<'a> {
479 : AuthenticationOk,
480 : AuthenticationMD5Password([u8; 4]),
481 : AuthenticationSasl(BeAuthenticationSaslMessage<'a>),
482 : AuthenticationCleartextPassword,
483 : BackendKeyData(CancelKeyData),
484 : BindComplete,
485 : CommandComplete(&'a [u8]),
486 : CopyData(&'a [u8]),
487 : CopyDone,
488 : CopyFail,
489 : CopyInResponse,
490 : CopyOutResponse,
491 : CopyBothResponse,
492 : CloseComplete,
493 : // None means column is NULL
494 : DataRow(&'a [Option<&'a [u8]>]),
495 : // None errcode means internal_error will be sent.
496 : ErrorResponse(&'a str, Option<&'a [u8; 5]>),
497 : /// Single byte - used in response to SSLRequest/GSSENCRequest.
498 : EncryptionResponse(bool),
499 : NoData,
500 : ParameterDescription,
501 : ParameterStatus {
502 : name: &'a [u8],
503 : value: &'a [u8],
504 : },
505 : ParseComplete,
506 : ReadyForQuery,
507 : RowDescription(&'a [RowDescriptor<'a>]),
508 : XLogData(XLogDataBody<'a>),
509 : NoticeResponse(&'a str),
510 : KeepAlive(WalSndKeepAlive),
511 : }
512 :
513 : /// Common shorthands.
514 : impl<'a> BeMessage<'a> {
515 : /// A [`BeMessage::ParameterStatus`] holding the client encoding, i.e. UTF-8.
516 : /// This is a sensible default, given that:
517 : /// * rust strings only support this encoding out of the box.
518 : /// * tokio-postgres, postgres-jdbc (and probably more) mandate it.
519 : ///
520 : /// TODO: do we need to report `server_encoding` as well?
521 : pub const CLIENT_ENCODING: Self = Self::ParameterStatus {
522 : name: b"client_encoding",
523 : value: b"UTF8",
524 : };
525 :
526 : pub const INTEGER_DATETIMES: Self = Self::ParameterStatus {
527 : name: b"integer_datetimes",
528 : value: b"on",
529 : };
530 :
531 : /// Build a [`BeMessage::ParameterStatus`] holding the server version.
532 8843 : pub fn server_version(version: &'a str) -> Self {
533 8843 : Self::ParameterStatus {
534 8843 : name: b"server_version",
535 8843 : value: version.as_bytes(),
536 8843 : }
537 8843 : }
538 : }
539 :
540 0 : #[derive(Debug)]
541 : pub enum BeAuthenticationSaslMessage<'a> {
542 : Methods(&'a [&'a str]),
543 : Continue(&'a [u8]),
544 : Final(&'a [u8]),
545 : }
546 :
547 0 : #[derive(Debug)]
548 : pub enum BeParameterStatusMessage<'a> {
549 : Encoding(&'a str),
550 : ServerVersion(&'a str),
551 : }
552 :
553 : // One row description in RowDescription packet.
554 0 : #[derive(Debug)]
555 : pub struct RowDescriptor<'a> {
556 : pub name: &'a [u8],
557 : pub tableoid: Oid,
558 : pub attnum: i16,
559 : pub typoid: Oid,
560 : pub typlen: i16,
561 : pub typmod: i32,
562 : pub formatcode: i16,
563 : }
564 :
565 : impl Default for RowDescriptor<'_> {
566 3099 : fn default() -> RowDescriptor<'static> {
567 3099 : RowDescriptor {
568 3099 : name: b"",
569 3099 : tableoid: 0,
570 3099 : attnum: 0,
571 3099 : typoid: 0,
572 3099 : typlen: 0,
573 3099 : typmod: 0,
574 3099 : formatcode: 0,
575 3099 : }
576 3099 : }
577 : }
578 :
579 : impl RowDescriptor<'_> {
580 : /// Convenience function to create a RowDescriptor message for an int8 column
581 45 : pub const fn int8_col(name: &[u8]) -> RowDescriptor {
582 45 : RowDescriptor {
583 45 : name,
584 45 : tableoid: 0,
585 45 : attnum: 0,
586 45 : typoid: INT8_OID,
587 45 : typlen: 8,
588 45 : typmod: 0,
589 45 : formatcode: 0,
590 45 : }
591 45 : }
592 :
593 1560 : pub const fn text_col(name: &[u8]) -> RowDescriptor {
594 1560 : RowDescriptor {
595 1560 : name,
596 1560 : tableoid: 0,
597 1560 : attnum: 0,
598 1560 : typoid: TEXT_OID,
599 1560 : typlen: -1,
600 1560 : typmod: 0,
601 1560 : formatcode: 0,
602 1560 : }
603 1560 : }
604 : }
605 :
606 0 : #[derive(Debug)]
607 : pub struct XLogDataBody<'a> {
608 : pub wal_start: u64,
609 : pub wal_end: u64, // current end of WAL on the server
610 : pub timestamp: i64,
611 : pub data: &'a [u8],
612 : }
613 :
614 0 : #[derive(Debug)]
615 : pub struct WalSndKeepAlive {
616 : pub wal_end: u64, // current end of WAL on the server
617 : pub timestamp: i64,
618 : pub request_reply: bool,
619 : }
620 :
621 : pub static HELLO_WORLD_ROW: BeMessage = BeMessage::DataRow(&[Some(b"hello world")]);
622 :
623 : // single text column
624 : pub static SINGLE_COL_ROWDESC: BeMessage = BeMessage::RowDescription(&[RowDescriptor {
625 : name: b"data",
626 : tableoid: 0,
627 : attnum: 0,
628 : typoid: TEXT_OID,
629 : typlen: -1,
630 : typmod: 0,
631 : formatcode: 0,
632 : }]);
633 :
634 : /// Call f() to write body of the message and prepend it with 4-byte len as
635 : /// prescribed by the protocol.
636 8628863 : fn write_body<R>(buf: &mut BytesMut, f: impl FnOnce(&mut BytesMut) -> R) -> R {
637 8628863 : let base = buf.len();
638 8628863 : buf.extend_from_slice(&[0; 4]);
639 8628863 :
640 8628863 : let res = f(buf);
641 8628863 :
642 8628863 : let size = i32::try_from(buf.len() - base).expect("message too big to transmit");
643 8628863 : (&mut buf[base..]).put_slice(&size.to_be_bytes());
644 8628863 :
645 8628863 : res
646 8628863 : }
647 :
648 : /// Safe write of s into buf as cstring (String in the protocol).
649 61453 : fn write_cstr(s: impl AsRef<[u8]>, buf: &mut BytesMut) -> Result<(), ProtocolError> {
650 61453 : let bytes = s.as_ref();
651 61453 : if bytes.contains(&0) {
652 0 : return Err(ProtocolError::BadMessage(
653 0 : "string contains embedded null".to_owned(),
654 0 : ));
655 61453 : }
656 61453 : buf.put_slice(bytes);
657 61453 : buf.put_u8(0);
658 61453 : Ok(())
659 61453 : }
660 :
661 : /// Read cstring from buf, advancing it.
662 3686889 : pub fn read_cstr(buf: &mut Bytes) -> Result<Bytes, ProtocolError> {
663 3686889 : let pos = buf
664 3686889 : .iter()
665 52352084 : .position(|x| *x == 0)
666 3686889 : .ok_or_else(|| ProtocolError::BadMessage("missing cstring terminator".to_owned()))?;
667 3686889 : let result = buf.split_to(pos);
668 3686889 : buf.advance(1); // drop the null terminator
669 3686889 : Ok(result)
670 3686889 : }
671 :
672 : pub const SQLSTATE_INTERNAL_ERROR: &[u8; 5] = b"XX000";
673 : pub const SQLSTATE_SUCCESSFUL_COMPLETION: &[u8; 5] = b"00000";
674 :
675 : impl<'a> BeMessage<'a> {
676 : /// Serialize `message` to the given `buf`.
677 : /// Apart from smart memory managemet, BytesMut is good here as msg len
678 : /// precedes its body and it is handy to write it down first and then fill
679 : /// the length. With Write we would have to either calc it manually or have
680 : /// one more buffer.
681 8635761 : pub fn write(buf: &mut BytesMut, message: &BeMessage) -> Result<(), ProtocolError> {
682 8635761 : match message {
683 9085 : BeMessage::AuthenticationOk => {
684 9085 : buf.put_u8(b'R');
685 9085 : write_body(buf, |buf| {
686 9085 : buf.put_i32(0); // Specifies that the authentication was successful.
687 9085 : });
688 9085 : }
689 :
690 219 : BeMessage::AuthenticationCleartextPassword => {
691 219 : buf.put_u8(b'R');
692 219 : write_body(buf, |buf| {
693 219 : buf.put_i32(3); // Specifies that clear text password is required.
694 219 : });
695 219 : }
696 :
697 0 : BeMessage::AuthenticationMD5Password(salt) => {
698 0 : buf.put_u8(b'R');
699 0 : write_body(buf, |buf| {
700 0 : buf.put_i32(5); // Specifies that an MD5-encrypted password is required.
701 0 : buf.put_slice(&salt[..]);
702 0 : });
703 0 : }
704 :
705 83 : BeMessage::AuthenticationSasl(msg) => {
706 83 : buf.put_u8(b'R');
707 83 : write_body(buf, |buf| {
708 83 : use BeAuthenticationSaslMessage::*;
709 83 : match msg {
710 29 : Methods(methods) => {
711 29 : buf.put_i32(10); // Specifies that SASL auth method is used.
712 29 : for method in methods.iter() {
713 29 : write_cstr(method, buf)?;
714 : }
715 29 : buf.put_u8(0); // zero terminator for the list
716 : }
717 29 : Continue(extra) => {
718 29 : buf.put_i32(11); // Continue SASL auth.
719 29 : buf.put_slice(extra);
720 29 : }
721 25 : Final(extra) => {
722 25 : buf.put_i32(12); // Send final SASL message.
723 25 : buf.put_slice(extra);
724 25 : }
725 : }
726 83 : Ok(())
727 83 : })?;
728 : }
729 :
730 27 : BeMessage::BackendKeyData(key_data) => {
731 27 : buf.put_u8(b'K');
732 27 : write_body(buf, |buf| {
733 27 : buf.put_i32(key_data.backend_pid);
734 27 : buf.put_i32(key_data.cancel_key);
735 27 : });
736 27 : }
737 :
738 662 : BeMessage::BindComplete => {
739 662 : buf.put_u8(b'2');
740 662 : write_body(buf, |_| {});
741 662 : }
742 :
743 661 : BeMessage::CloseComplete => {
744 661 : buf.put_u8(b'3');
745 661 : write_body(buf, |_| {});
746 661 : }
747 :
748 2262 : BeMessage::CommandComplete(cmd) => {
749 2262 : buf.put_u8(b'C');
750 2262 : write_body(buf, |buf| write_cstr(cmd, buf))?;
751 : }
752 :
753 7813023 : BeMessage::CopyData(data) => {
754 7813023 : buf.put_u8(b'd');
755 7813023 : write_body(buf, |buf| {
756 7813023 : buf.put_slice(data);
757 7813023 : });
758 7813023 : }
759 :
760 660 : BeMessage::CopyDone => {
761 660 : buf.put_u8(b'c');
762 660 : write_body(buf, |_| {});
763 660 : }
764 :
765 0 : BeMessage::CopyFail => {
766 0 : buf.put_u8(b'f');
767 0 : write_body(buf, |_| {});
768 0 : }
769 :
770 7 : BeMessage::CopyInResponse => {
771 7 : buf.put_u8(b'G');
772 7 : write_body(buf, |buf| {
773 7 : buf.put_u8(1); // copy_is_binary
774 7 : buf.put_i16(0); // numAttributes
775 7 : });
776 7 : }
777 :
778 662 : BeMessage::CopyOutResponse => {
779 662 : buf.put_u8(b'H');
780 662 : write_body(buf, |buf| {
781 662 : buf.put_u8(0); // copy_is_binary
782 662 : buf.put_i16(0); // numAttributes
783 662 : });
784 662 : }
785 :
786 7488 : BeMessage::CopyBothResponse => {
787 7488 : buf.put_u8(b'W');
788 7488 : write_body(buf, |buf| {
789 7488 : // doesn't matter, used only for replication
790 7488 : buf.put_u8(0); // copy_is_binary
791 7488 : buf.put_i16(0); // numAttributes
792 7488 : });
793 7488 : }
794 :
795 1056 : BeMessage::DataRow(vals) => {
796 1056 : buf.put_u8(b'D');
797 1056 : write_body(buf, |buf| {
798 1056 : buf.put_u16(vals.len() as u16); // num of cols
799 3687 : for val_opt in vals.iter() {
800 3687 : if let Some(val) = val_opt {
801 2913 : buf.put_u32(val.len() as u32);
802 2913 : buf.put_slice(val);
803 2913 : } else {
804 774 : buf.put_i32(-1);
805 774 : }
806 : }
807 1056 : });
808 1056 : }
809 :
810 : // ErrorResponse is a zero-terminated array of zero-terminated fields.
811 : // First byte of each field represents type of this field. Set just enough fields
812 : // to satisfy rust-postgres client: 'S' -- severity, 'C' -- error, 'M' -- error
813 : // message text.
814 253 : BeMessage::ErrorResponse(error_msg, pg_error_code) => {
815 253 : // 'E' signalizes ErrorResponse messages
816 253 : buf.put_u8(b'E');
817 253 : write_body(buf, |buf| {
818 253 : buf.put_u8(b'S'); // severity
819 253 : buf.put_slice(b"ERROR\0");
820 253 :
821 253 : buf.put_u8(b'C'); // SQLSTATE error code
822 253 : buf.put_slice(&terminate_code(
823 253 : pg_error_code.unwrap_or(SQLSTATE_INTERNAL_ERROR),
824 253 : ));
825 253 :
826 253 : buf.put_u8(b'M'); // the message
827 253 : write_cstr(error_msg, buf)?;
828 :
829 253 : buf.put_u8(0); // terminator
830 253 : Ok(())
831 253 : })?;
832 : }
833 :
834 : // NoticeResponse has the same format as ErrorResponse. From doc: "The frontend should display the
835 : // message but continue listening for ReadyForQuery or ErrorResponse"
836 6 : BeMessage::NoticeResponse(error_msg) => {
837 6 : // For all the errors set Severity to Error and error code to
838 6 : // 'internal error'.
839 6 :
840 6 : // 'N' signalizes NoticeResponse messages
841 6 : buf.put_u8(b'N');
842 6 : write_body(buf, |buf| {
843 6 : buf.put_u8(b'S'); // severity
844 6 : buf.put_slice(b"NOTICE\0");
845 6 :
846 6 : buf.put_u8(b'C'); // SQLSTATE error code
847 6 : buf.put_slice(&terminate_code(SQLSTATE_INTERNAL_ERROR));
848 6 :
849 6 : buf.put_u8(b'M'); // the message
850 6 : write_cstr(error_msg.as_bytes(), buf)?;
851 :
852 6 : buf.put_u8(0); // terminator
853 6 : Ok(())
854 6 : })?;
855 : }
856 :
857 662 : BeMessage::NoData => {
858 662 : buf.put_u8(b'n');
859 662 : write_body(buf, |_| {});
860 662 : }
861 :
862 6898 : BeMessage::EncryptionResponse(should_negotiate) => {
863 6898 : let response = if *should_negotiate { b'S' } else { b'N' };
864 6898 : buf.put_u8(response);
865 : }
866 :
867 27098 : BeMessage::ParameterStatus { name, value } => {
868 27098 : buf.put_u8(b'S');
869 27098 : write_body(buf, |buf| {
870 27098 : write_cstr(name, buf)?;
871 27098 : write_cstr(value, buf)
872 27098 : })?;
873 : }
874 :
875 662 : BeMessage::ParameterDescription => {
876 662 : buf.put_u8(b't');
877 662 : write_body(buf, |buf| {
878 662 : // we don't support params, so always 0
879 662 : buf.put_i16(0);
880 662 : });
881 662 : }
882 :
883 662 : BeMessage::ParseComplete => {
884 662 : buf.put_u8(b'1');
885 662 : write_body(buf, |_| {});
886 662 : }
887 :
888 19814 : BeMessage::ReadyForQuery => {
889 19814 : buf.put_u8(b'Z');
890 19814 : write_body(buf, |buf| {
891 19814 : buf.put_u8(b'I');
892 19814 : });
893 19814 : }
894 :
895 1566 : BeMessage::RowDescription(rows) => {
896 1566 : buf.put_u8(b'T');
897 1566 : write_body(buf, |buf| {
898 1566 : buf.put_i16(rows.len() as i16); // # of fields
899 4707 : for row in rows.iter() {
900 4707 : write_cstr(row.name, buf)?;
901 4707 : buf.put_i32(0); /* table oid */
902 4707 : buf.put_i16(0); /* attnum */
903 4707 : buf.put_u32(row.typoid);
904 4707 : buf.put_i16(row.typlen);
905 4707 : buf.put_i32(-1); /* typmod */
906 4707 : buf.put_i16(0); /* format code */
907 : }
908 1566 : Ok(())
909 1566 : })?;
910 : }
911 :
912 740437 : BeMessage::XLogData(body) => {
913 740437 : buf.put_u8(b'd');
914 740437 : write_body(buf, |buf| {
915 740437 : buf.put_u8(b'w');
916 740437 : buf.put_u64(body.wal_start);
917 740437 : buf.put_u64(body.wal_end);
918 740437 : buf.put_i64(body.timestamp);
919 740437 : buf.put_slice(body.data);
920 740437 : });
921 740437 : }
922 :
923 1808 : BeMessage::KeepAlive(req) => {
924 1808 : buf.put_u8(b'd');
925 1808 : write_body(buf, |buf| {
926 1808 : buf.put_u8(b'k');
927 1808 : buf.put_u64(req.wal_end);
928 1808 : buf.put_i64(req.timestamp);
929 1808 : buf.put_u8(u8::from(req.request_reply));
930 1808 : });
931 1808 : }
932 : }
933 8635761 : Ok(())
934 8635761 : }
935 : }
936 :
937 259 : fn terminate_code(code: &[u8; 5]) -> [u8; 6] {
938 259 : let mut terminated = [0; 6];
939 1295 : for (i, &elem) in code.iter().enumerate() {
940 1295 : terminated[i] = elem;
941 1295 : }
942 :
943 259 : terminated
944 259 : }
945 :
946 : #[cfg(test)]
947 : mod tests {
948 : use super::*;
949 :
950 1 : #[test]
951 1 : fn test_startup_message_params_options_escaped() {
952 4 : fn split_options(params: &StartupMessageParams) -> Vec<Cow<'_, str>> {
953 4 : params
954 4 : .options_escaped()
955 4 : .expect("options are None")
956 4 : .collect()
957 4 : }
958 1 :
959 4 : let make_params = |options| StartupMessageParams::new([("options", options)]);
960 :
961 1 : let params = StartupMessageParams::new([]);
962 1 : assert!(matches!(params.options_escaped(), None));
963 :
964 1 : let params = make_params("");
965 1 : assert!(split_options(¶ms).is_empty());
966 :
967 1 : let params = make_params("foo");
968 1 : assert_eq!(split_options(¶ms), ["foo"]);
969 :
970 1 : let params = make_params(" foo bar ");
971 1 : assert_eq!(split_options(¶ms), ["foo", "bar"]);
972 :
973 1 : let params = make_params("foo\\ bar \\ \\\\ baz\\ lol");
974 1 : assert_eq!(split_options(¶ms), ["foo bar", " \\", "baz ", "lol"]);
975 1 : }
976 : }
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