chore(proxy): vendor a subset of rust-postgres (#9930)

Our rust-postgres fork is getting messy. Mostly because proxy wants more
control over the raw protocol than tokio-postgres provides. As such,
it's diverging more and more. Storage and compute also make use of
rust-postgres, but in more normal usage, thus they don't need our crazy
changes.

Idea: 
* proxy maintains their subset
* other teams use a minimal patch set against upstream rust-postgres

Reviewing this code will be difficult. To implement it, I
1. Copied tokio-postgres, postgres-protocol and postgres-types from
00940fcdb5
2. Updated their package names with the `2` suffix to make them compile
in the workspace.
3. Updated proxy to use those packages
4. Copied in the code from tokio-postgres-rustls 0.13 (with some patches
applied https://github.com/jbg/tokio-postgres-rustls/pull/32
https://github.com/jbg/tokio-postgres-rustls/pull/33)
5. Removed as much dead code as I could find in the vendored libraries
6. Updated the tokio-postgres-rustls code to use our existing channel
binding implementation

libs/proxy/postgres-protocol2/src/message/backend.rs

@@ -0,0 +1,766 @@
+#![allow(missing_docs)]
+
+use byteorder::{BigEndian, ByteOrder, ReadBytesExt};
+use bytes::{Bytes, BytesMut};
+use fallible_iterator::FallibleIterator;
+use memchr::memchr;
+use std::cmp;
+use std::io::{self, Read};
+use std::ops::Range;
+use std::str;
+
+use crate::Oid;
+
+// top-level message tags
+const PARSE_COMPLETE_TAG: u8 = b'1';
+const BIND_COMPLETE_TAG: u8 = b'2';
+const CLOSE_COMPLETE_TAG: u8 = b'3';
+pub const NOTIFICATION_RESPONSE_TAG: u8 = b'A';
+const COPY_DONE_TAG: u8 = b'c';
+const COMMAND_COMPLETE_TAG: u8 = b'C';
+const COPY_DATA_TAG: u8 = b'd';
+const DATA_ROW_TAG: u8 = b'D';
+const ERROR_RESPONSE_TAG: u8 = b'E';
+const COPY_IN_RESPONSE_TAG: u8 = b'G';
+const COPY_OUT_RESPONSE_TAG: u8 = b'H';
+const COPY_BOTH_RESPONSE_TAG: u8 = b'W';
+const EMPTY_QUERY_RESPONSE_TAG: u8 = b'I';
+const BACKEND_KEY_DATA_TAG: u8 = b'K';
+pub const NO_DATA_TAG: u8 = b'n';
+pub const NOTICE_RESPONSE_TAG: u8 = b'N';
+const AUTHENTICATION_TAG: u8 = b'R';
+const PORTAL_SUSPENDED_TAG: u8 = b's';
+pub const PARAMETER_STATUS_TAG: u8 = b'S';
+const PARAMETER_DESCRIPTION_TAG: u8 = b't';
+const ROW_DESCRIPTION_TAG: u8 = b'T';
+pub const READY_FOR_QUERY_TAG: u8 = b'Z';
+
+#[derive(Debug, Copy, Clone)]
+pub struct Header {
+    tag: u8,
+    len: i32,
+}
+
+#[allow(clippy::len_without_is_empty)]
+impl Header {
+    #[inline]
+    pub fn parse(buf: &[u8]) -> io::Result<Option<Header>> {
+        if buf.len() < 5 {
+            return Ok(None);
+        }
+
+        let tag = buf[0];
+        let len = BigEndian::read_i32(&buf[1..]);
+
+        if len < 4 {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidData,
+                "invalid message length: header length < 4",
+            ));
+        }
+
+        Ok(Some(Header { tag, len }))
+    }
+
+    #[inline]
+    pub fn tag(self) -> u8 {
+        self.tag
+    }
+
+    #[inline]
+    pub fn len(self) -> i32 {
+        self.len
+    }
+}
+
+/// An enum representing Postgres backend messages.
+#[non_exhaustive]
+pub enum Message {
+    AuthenticationCleartextPassword,
+    AuthenticationGss,
+    AuthenticationKerberosV5,
+    AuthenticationMd5Password(AuthenticationMd5PasswordBody),
+    AuthenticationOk,
+    AuthenticationScmCredential,
+    AuthenticationSspi,
+    AuthenticationGssContinue,
+    AuthenticationSasl(AuthenticationSaslBody),
+    AuthenticationSaslContinue(AuthenticationSaslContinueBody),
+    AuthenticationSaslFinal(AuthenticationSaslFinalBody),
+    BackendKeyData(BackendKeyDataBody),
+    BindComplete,
+    CloseComplete,
+    CommandComplete(CommandCompleteBody),
+    CopyData,
+    CopyDone,
+    CopyInResponse,
+    CopyOutResponse,
+    CopyBothResponse,
+    DataRow(DataRowBody),
+    EmptyQueryResponse,
+    ErrorResponse(ErrorResponseBody),
+    NoData,
+    NoticeResponse(NoticeResponseBody),
+    NotificationResponse(NotificationResponseBody),
+    ParameterDescription(ParameterDescriptionBody),
+    ParameterStatus(ParameterStatusBody),
+    ParseComplete,
+    PortalSuspended,
+    ReadyForQuery(ReadyForQueryBody),
+    RowDescription(RowDescriptionBody),
+}
+
+impl Message {
+    #[inline]
+    pub fn parse(buf: &mut BytesMut) -> io::Result<Option<Message>> {
+        if buf.len() < 5 {
+            let to_read = 5 - buf.len();
+            buf.reserve(to_read);
+            return Ok(None);
+        }
+
+        let tag = buf[0];
+        let len = (&buf[1..5]).read_u32::<BigEndian>().unwrap();
+
+        if len < 4 {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidInput,
+                "invalid message length: parsing u32",
+            ));
+        }
+
+        let total_len = len as usize + 1;
+        if buf.len() < total_len {
+            let to_read = total_len - buf.len();
+            buf.reserve(to_read);
+            return Ok(None);
+        }
+
+        let mut buf = Buffer {
+            bytes: buf.split_to(total_len).freeze(),
+            idx: 5,
+        };
+
+        let message = match tag {
+            PARSE_COMPLETE_TAG => Message::ParseComplete,
+            BIND_COMPLETE_TAG => Message::BindComplete,
+            CLOSE_COMPLETE_TAG => Message::CloseComplete,
+            NOTIFICATION_RESPONSE_TAG => {
+                let process_id = buf.read_i32::<BigEndian>()?;
+                let channel = buf.read_cstr()?;
+                let message = buf.read_cstr()?;
+                Message::NotificationResponse(NotificationResponseBody {
+                    process_id,
+                    channel,
+                    message,
+                })
+            }
+            COPY_DONE_TAG => Message::CopyDone,
+            COMMAND_COMPLETE_TAG => {
+                let tag = buf.read_cstr()?;
+                Message::CommandComplete(CommandCompleteBody { tag })
+            }
+            COPY_DATA_TAG => Message::CopyData,
+            DATA_ROW_TAG => {
+                let len = buf.read_u16::<BigEndian>()?;
+                let storage = buf.read_all();
+                Message::DataRow(DataRowBody { storage, len })
+            }
+            ERROR_RESPONSE_TAG => {
+                let storage = buf.read_all();
+                Message::ErrorResponse(ErrorResponseBody { storage })
+            }
+            COPY_IN_RESPONSE_TAG => Message::CopyInResponse,
+            COPY_OUT_RESPONSE_TAG => Message::CopyOutResponse,
+            COPY_BOTH_RESPONSE_TAG => Message::CopyBothResponse,
+            EMPTY_QUERY_RESPONSE_TAG => Message::EmptyQueryResponse,
+            BACKEND_KEY_DATA_TAG => {
+                let process_id = buf.read_i32::<BigEndian>()?;
+                let secret_key = buf.read_i32::<BigEndian>()?;
+                Message::BackendKeyData(BackendKeyDataBody {
+                    process_id,
+                    secret_key,
+                })
+            }
+            NO_DATA_TAG => Message::NoData,
+            NOTICE_RESPONSE_TAG => {
+                let storage = buf.read_all();
+                Message::NoticeResponse(NoticeResponseBody { storage })
+            }
+            AUTHENTICATION_TAG => match buf.read_i32::<BigEndian>()? {
+                0 => Message::AuthenticationOk,
+                2 => Message::AuthenticationKerberosV5,
+                3 => Message::AuthenticationCleartextPassword,
+                5 => {
+                    let mut salt = [0; 4];
+                    buf.read_exact(&mut salt)?;
+                    Message::AuthenticationMd5Password(AuthenticationMd5PasswordBody { salt })
+                }
+                6 => Message::AuthenticationScmCredential,
+                7 => Message::AuthenticationGss,
+                8 => Message::AuthenticationGssContinue,
+                9 => Message::AuthenticationSspi,
+                10 => {
+                    let storage = buf.read_all();
+                    Message::AuthenticationSasl(AuthenticationSaslBody(storage))
+                }
+                11 => {
+                    let storage = buf.read_all();
+                    Message::AuthenticationSaslContinue(AuthenticationSaslContinueBody(storage))
+                }
+                12 => {
+                    let storage = buf.read_all();
+                    Message::AuthenticationSaslFinal(AuthenticationSaslFinalBody(storage))
+                }
+                tag => {
+                    return Err(io::Error::new(
+                        io::ErrorKind::InvalidInput,
+                        format!("unknown authentication tag `{}`", tag),
+                    ));
+                }
+            },
+            PORTAL_SUSPENDED_TAG => Message::PortalSuspended,
+            PARAMETER_STATUS_TAG => {
+                let name = buf.read_cstr()?;
+                let value = buf.read_cstr()?;
+                Message::ParameterStatus(ParameterStatusBody { name, value })
+            }
+            PARAMETER_DESCRIPTION_TAG => {
+                let len = buf.read_u16::<BigEndian>()?;
+                let storage = buf.read_all();
+                Message::ParameterDescription(ParameterDescriptionBody { storage, len })
+            }
+            ROW_DESCRIPTION_TAG => {
+                let len = buf.read_u16::<BigEndian>()?;
+                let storage = buf.read_all();
+                Message::RowDescription(RowDescriptionBody { storage, len })
+            }
+            READY_FOR_QUERY_TAG => {
+                let status = buf.read_u8()?;
+                Message::ReadyForQuery(ReadyForQueryBody { status })
+            }
+            tag => {
+                return Err(io::Error::new(
+                    io::ErrorKind::InvalidInput,
+                    format!("unknown message tag `{}`", tag),
+                ));
+            }
+        };
+
+        if !buf.is_empty() {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidInput,
+                "invalid message length: expected buffer to be empty",
+            ));
+        }
+
+        Ok(Some(message))
+    }
+}
+
+struct Buffer {
+    bytes: Bytes,
+    idx: usize,
+}
+
+impl Buffer {
+    #[inline]
+    fn slice(&self) -> &[u8] {
+        &self.bytes[self.idx..]
+    }
+
+    #[inline]
+    fn is_empty(&self) -> bool {
+        self.slice().is_empty()
+    }
+
+    #[inline]
+    fn read_cstr(&mut self) -> io::Result<Bytes> {
+        match memchr(0, self.slice()) {
+            Some(pos) => {
+                let start = self.idx;
+                let end = start + pos;
+                let cstr = self.bytes.slice(start..end);
+                self.idx = end + 1;
+                Ok(cstr)
+            }
+            None => Err(io::Error::new(
+                io::ErrorKind::UnexpectedEof,
+                "unexpected EOF",
+            )),
+        }
+    }
+
+    #[inline]
+    fn read_all(&mut self) -> Bytes {
+        let buf = self.bytes.slice(self.idx..);
+        self.idx = self.bytes.len();
+        buf
+    }
+}
+
+impl Read for Buffer {
+    #[inline]
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        let len = {
+            let slice = self.slice();
+            let len = cmp::min(slice.len(), buf.len());
+            buf[..len].copy_from_slice(&slice[..len]);
+            len
+        };
+        self.idx += len;
+        Ok(len)
+    }
+}
+
+pub struct AuthenticationMd5PasswordBody {
+    salt: [u8; 4],
+}
+
+impl AuthenticationMd5PasswordBody {
+    #[inline]
+    pub fn salt(&self) -> [u8; 4] {
+        self.salt
+    }
+}
+
+pub struct AuthenticationSaslBody(Bytes);
+
+impl AuthenticationSaslBody {
+    #[inline]
+    pub fn mechanisms(&self) -> SaslMechanisms<'_> {
+        SaslMechanisms(&self.0)
+    }
+}
+
+pub struct SaslMechanisms<'a>(&'a [u8]);
+
+impl<'a> FallibleIterator for SaslMechanisms<'a> {
+    type Item = &'a str;
+    type Error = io::Error;
+
+    #[inline]
+    fn next(&mut self) -> io::Result<Option<&'a str>> {
+        let value_end = find_null(self.0, 0)?;
+        if value_end == 0 {
+            if self.0.len() != 1 {
+                return Err(io::Error::new(
+                    io::ErrorKind::InvalidData,
+                    "invalid message length: expected to be at end of iterator for sasl",
+                ));
+            }
+            Ok(None)
+        } else {
+            let value = get_str(&self.0[..value_end])?;
+            self.0 = &self.0[value_end + 1..];
+            Ok(Some(value))
+        }
+    }
+}
+
+pub struct AuthenticationSaslContinueBody(Bytes);
+
+impl AuthenticationSaslContinueBody {
+    #[inline]
+    pub fn data(&self) -> &[u8] {
+        &self.0
+    }
+}
+
+pub struct AuthenticationSaslFinalBody(Bytes);
+
+impl AuthenticationSaslFinalBody {
+    #[inline]
+    pub fn data(&self) -> &[u8] {
+        &self.0
+    }
+}
+
+pub struct BackendKeyDataBody {
+    process_id: i32,
+    secret_key: i32,
+}
+
+impl BackendKeyDataBody {
+    #[inline]
+    pub fn process_id(&self) -> i32 {
+        self.process_id
+    }
+
+    #[inline]
+    pub fn secret_key(&self) -> i32 {
+        self.secret_key
+    }
+}
+
+pub struct CommandCompleteBody {
+    tag: Bytes,
+}
+
+impl CommandCompleteBody {
+    #[inline]
+    pub fn tag(&self) -> io::Result<&str> {
+        get_str(&self.tag)
+    }
+}
+
+#[derive(Debug)]
+pub struct DataRowBody {
+    storage: Bytes,
+    len: u16,
+}
+
+impl DataRowBody {
+    #[inline]
+    pub fn ranges(&self) -> DataRowRanges<'_> {
+        DataRowRanges {
+            buf: &self.storage,
+            len: self.storage.len(),
+            remaining: self.len,
+        }
+    }
+
+    #[inline]
+    pub fn buffer(&self) -> &[u8] {
+        &self.storage
+    }
+}
+
+pub struct DataRowRanges<'a> {
+    buf: &'a [u8],
+    len: usize,
+    remaining: u16,
+}
+
+impl FallibleIterator for DataRowRanges<'_> {
+    type Item = Option<Range<usize>>;
+    type Error = io::Error;
+
+    #[inline]
+    fn next(&mut self) -> io::Result<Option<Option<Range<usize>>>> {
+        if self.remaining == 0 {
+            if self.buf.is_empty() {
+                return Ok(None);
+            } else {
+                return Err(io::Error::new(
+                    io::ErrorKind::InvalidInput,
+                    "invalid message length: datarowrange is not empty",
+                ));
+            }
+        }
+
+        self.remaining -= 1;
+        let len = self.buf.read_i32::<BigEndian>()?;
+        if len < 0 {
+            Ok(Some(None))
+        } else {
+            let len = len as usize;
+            if self.buf.len() < len {
+                return Err(io::Error::new(
+                    io::ErrorKind::UnexpectedEof,
+                    "unexpected EOF",
+                ));
+            }
+            let base = self.len - self.buf.len();
+            self.buf = &self.buf[len..];
+            Ok(Some(Some(base..base + len)))
+        }
+    }
+
+    #[inline]
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        let len = self.remaining as usize;
+        (len, Some(len))
+    }
+}
+
+pub struct ErrorResponseBody {
+    storage: Bytes,
+}
+
+impl ErrorResponseBody {
+    #[inline]
+    pub fn fields(&self) -> ErrorFields<'_> {
+        ErrorFields { buf: &self.storage }
+    }
+}
+
+pub struct ErrorFields<'a> {
+    buf: &'a [u8],
+}
+
+impl<'a> FallibleIterator for ErrorFields<'a> {
+    type Item = ErrorField<'a>;
+    type Error = io::Error;
+
+    #[inline]
+    fn next(&mut self) -> io::Result<Option<ErrorField<'a>>> {
+        let type_ = self.buf.read_u8()?;
+        if type_ == 0 {
+            if self.buf.is_empty() {
+                return Ok(None);
+            } else {
+                return Err(io::Error::new(
+                    io::ErrorKind::InvalidInput,
+                    "invalid message length: error fields is not drained",
+                ));
+            }
+        }
+
+        let value_end = find_null(self.buf, 0)?;
+        let value = get_str(&self.buf[..value_end])?;
+        self.buf = &self.buf[value_end + 1..];
+
+        Ok(Some(ErrorField { type_, value }))
+    }
+}
+
+pub struct ErrorField<'a> {
+    type_: u8,
+    value: &'a str,
+}
+
+impl ErrorField<'_> {
+    #[inline]
+    pub fn type_(&self) -> u8 {
+        self.type_
+    }
+
+    #[inline]
+    pub fn value(&self) -> &str {
+        self.value
+    }
+}
+
+pub struct NoticeResponseBody {
+    storage: Bytes,
+}
+
+impl NoticeResponseBody {
+    #[inline]
+    pub fn fields(&self) -> ErrorFields<'_> {
+        ErrorFields { buf: &self.storage }
+    }
+}
+
+pub struct NotificationResponseBody {
+    process_id: i32,
+    channel: Bytes,
+    message: Bytes,
+}
+
+impl NotificationResponseBody {
+    #[inline]
+    pub fn process_id(&self) -> i32 {
+        self.process_id
+    }
+
+    #[inline]
+    pub fn channel(&self) -> io::Result<&str> {
+        get_str(&self.channel)
+    }
+
+    #[inline]
+    pub fn message(&self) -> io::Result<&str> {
+        get_str(&self.message)
+    }
+}
+
+pub struct ParameterDescriptionBody {
+    storage: Bytes,
+    len: u16,
+}
+
+impl ParameterDescriptionBody {
+    #[inline]
+    pub fn parameters(&self) -> Parameters<'_> {
+        Parameters {
+            buf: &self.storage,
+            remaining: self.len,
+        }
+    }
+}
+
+pub struct Parameters<'a> {
+    buf: &'a [u8],
+    remaining: u16,
+}
+
+impl FallibleIterator for Parameters<'_> {
+    type Item = Oid;
+    type Error = io::Error;
+
+    #[inline]
+    fn next(&mut self) -> io::Result<Option<Oid>> {
+        if self.remaining == 0 {
+            if self.buf.is_empty() {
+                return Ok(None);
+            } else {
+                return Err(io::Error::new(
+                    io::ErrorKind::InvalidInput,
+                    "invalid message length: parameters is not drained",
+                ));
+            }
+        }
+
+        self.remaining -= 1;
+        self.buf.read_u32::<BigEndian>().map(Some)
+    }
+
+    #[inline]
+    fn size_hint(&self) -> (usize, Option<usize>) {
+        let len = self.remaining as usize;
+        (len, Some(len))
+    }
+}
+
+pub struct ParameterStatusBody {
+    name: Bytes,
+    value: Bytes,
+}
+
+impl ParameterStatusBody {
+    #[inline]
+    pub fn name(&self) -> io::Result<&str> {
+        get_str(&self.name)
+    }
+
+    #[inline]
+    pub fn value(&self) -> io::Result<&str> {
+        get_str(&self.value)
+    }
+}
+
+pub struct ReadyForQueryBody {
+    status: u8,
+}
+
+impl ReadyForQueryBody {
+    #[inline]
+    pub fn status(&self) -> u8 {
+        self.status
+    }
+}
+
+pub struct RowDescriptionBody {
+    storage: Bytes,
+    len: u16,
+}
+
+impl RowDescriptionBody {
+    #[inline]
+    pub fn fields(&self) -> Fields<'_> {
+        Fields {
+            buf: &self.storage,
+            remaining: self.len,
+        }
+    }
+}
+
+pub struct Fields<'a> {
+    buf: &'a [u8],
+    remaining: u16,
+}
+
+impl<'a> FallibleIterator for Fields<'a> {
+    type Item = Field<'a>;
+    type Error = io::Error;
+
+    #[inline]
+    fn next(&mut self) -> io::Result<Option<Field<'a>>> {
+        if self.remaining == 0 {
+            if self.buf.is_empty() {
+                return Ok(None);
+            } else {
+                return Err(io::Error::new(
+                    io::ErrorKind::InvalidInput,
+                    "invalid message length: field is not drained",
+                ));
+            }
+        }
+
+        self.remaining -= 1;
+        let name_end = find_null(self.buf, 0)?;
+        let name = get_str(&self.buf[..name_end])?;
+        self.buf = &self.buf[name_end + 1..];
+        let table_oid = self.buf.read_u32::<BigEndian>()?;
+        let column_id = self.buf.read_i16::<BigEndian>()?;
+        let type_oid = self.buf.read_u32::<BigEndian>()?;
+        let type_size = self.buf.read_i16::<BigEndian>()?;
+        let type_modifier = self.buf.read_i32::<BigEndian>()?;
+        let format = self.buf.read_i16::<BigEndian>()?;
+
+        Ok(Some(Field {
+            name,
+            table_oid,
+            column_id,
+            type_oid,
+            type_size,
+            type_modifier,
+            format,
+        }))
+    }
+}
+
+pub struct Field<'a> {
+    name: &'a str,
+    table_oid: Oid,
+    column_id: i16,
+    type_oid: Oid,
+    type_size: i16,
+    type_modifier: i32,
+    format: i16,
+}
+
+impl<'a> Field<'a> {
+    #[inline]
+    pub fn name(&self) -> &'a str {
+        self.name
+    }
+
+    #[inline]
+    pub fn table_oid(&self) -> Oid {
+        self.table_oid
+    }
+
+    #[inline]
+    pub fn column_id(&self) -> i16 {
+        self.column_id
+    }
+
+    #[inline]
+    pub fn type_oid(&self) -> Oid {
+        self.type_oid
+    }
+
+    #[inline]
+    pub fn type_size(&self) -> i16 {
+        self.type_size
+    }
+
+    #[inline]
+    pub fn type_modifier(&self) -> i32 {
+        self.type_modifier
+    }
+
+    #[inline]
+    pub fn format(&self) -> i16 {
+        self.format
+    }
+}
+
+#[inline]
+fn find_null(buf: &[u8], start: usize) -> io::Result<usize> {
+    match memchr(0, &buf[start..]) {
+        Some(pos) => Ok(pos + start),
+        None => Err(io::Error::new(
+            io::ErrorKind::UnexpectedEof,
+            "unexpected EOF",
+        )),
+    }
+}
+
+#[inline]
+fn get_str(buf: &[u8]) -> io::Result<&str> {
+    str::from_utf8(buf).map_err(|e| io::Error::new(io::ErrorKind::InvalidInput, e))
+}

libs/proxy/postgres-protocol2/src/message/frontend.rs

@@ -0,0 +1,297 @@
+//! Frontend message serialization.
+#![allow(missing_docs)]
+
+use byteorder::{BigEndian, ByteOrder};
+use bytes::{Buf, BufMut, BytesMut};
+use std::convert::TryFrom;
+use std::error::Error;
+use std::io;
+use std::marker;
+
+use crate::{write_nullable, FromUsize, IsNull, Oid};
+
+#[inline]
+fn write_body<F, E>(buf: &mut BytesMut, f: F) -> Result<(), E>
+where
+    F: FnOnce(&mut BytesMut) -> Result<(), E>,
+    E: From<io::Error>,
+{
+    let base = buf.len();
+    buf.extend_from_slice(&[0; 4]);
+
+    f(buf)?;
+
+    let size = i32::from_usize(buf.len() - base)?;
+    BigEndian::write_i32(&mut buf[base..], size);
+    Ok(())
+}
+
+pub enum BindError {
+    Conversion(Box<dyn Error + marker::Sync + Send>),
+    Serialization(io::Error),
+}
+
+impl From<Box<dyn Error + marker::Sync + Send>> for BindError {
+    #[inline]
+    fn from(e: Box<dyn Error + marker::Sync + Send>) -> BindError {
+        BindError::Conversion(e)
+    }
+}
+
+impl From<io::Error> for BindError {
+    #[inline]
+    fn from(e: io::Error) -> BindError {
+        BindError::Serialization(e)
+    }
+}
+
+#[inline]
+pub fn bind<I, J, F, T, K>(
+    portal: &str,
+    statement: &str,
+    formats: I,
+    values: J,
+    mut serializer: F,
+    result_formats: K,
+    buf: &mut BytesMut,
+) -> Result<(), BindError>
+where
+    I: IntoIterator<Item = i16>,
+    J: IntoIterator<Item = T>,
+    F: FnMut(T, &mut BytesMut) -> Result<IsNull, Box<dyn Error + marker::Sync + Send>>,
+    K: IntoIterator<Item = i16>,
+{
+    buf.put_u8(b'B');
+
+    write_body(buf, |buf| {
+        write_cstr(portal.as_bytes(), buf)?;
+        write_cstr(statement.as_bytes(), buf)?;
+        write_counted(
+            formats,
+            |f, buf| {
+                buf.put_i16(f);
+                Ok::<_, io::Error>(())
+            },
+            buf,
+        )?;
+        write_counted(
+            values,
+            |v, buf| write_nullable(|buf| serializer(v, buf), buf),
+            buf,
+        )?;
+        write_counted(
+            result_formats,
+            |f, buf| {
+                buf.put_i16(f);
+                Ok::<_, io::Error>(())
+            },
+            buf,
+        )?;
+
+        Ok(())
+    })
+}
+
+#[inline]
+fn write_counted<I, T, F, E>(items: I, mut serializer: F, buf: &mut BytesMut) -> Result<(), E>
+where
+    I: IntoIterator<Item = T>,
+    F: FnMut(T, &mut BytesMut) -> Result<(), E>,
+    E: From<io::Error>,
+{
+    let base = buf.len();
+    buf.extend_from_slice(&[0; 2]);
+    let mut count = 0;
+    for item in items {
+        serializer(item, buf)?;
+        count += 1;
+    }
+    let count = i16::from_usize(count)?;
+    BigEndian::write_i16(&mut buf[base..], count);
+
+    Ok(())
+}
+
+#[inline]
+pub fn cancel_request(process_id: i32, secret_key: i32, buf: &mut BytesMut) {
+    write_body(buf, |buf| {
+        buf.put_i32(80_877_102);
+        buf.put_i32(process_id);
+        buf.put_i32(secret_key);
+        Ok::<_, io::Error>(())
+    })
+    .unwrap();
+}
+
+#[inline]
+pub fn close(variant: u8, name: &str, buf: &mut BytesMut) -> io::Result<()> {
+    buf.put_u8(b'C');
+    write_body(buf, |buf| {
+        buf.put_u8(variant);
+        write_cstr(name.as_bytes(), buf)
+    })
+}
+
+pub struct CopyData<T> {
+    buf: T,
+    len: i32,
+}
+
+impl<T> CopyData<T>
+where
+    T: Buf,
+{
+    pub fn new(buf: T) -> io::Result<CopyData<T>> {
+        let len = buf
+            .remaining()
+            .checked_add(4)
+            .and_then(|l| i32::try_from(l).ok())
+            .ok_or_else(|| {
+                io::Error::new(io::ErrorKind::InvalidInput, "message length overflow")
+            })?;
+
+        Ok(CopyData { buf, len })
+    }
+
+    pub fn write(self, out: &mut BytesMut) {
+        out.put_u8(b'd');
+        out.put_i32(self.len);
+        out.put(self.buf);
+    }
+}
+
+#[inline]
+pub fn copy_done(buf: &mut BytesMut) {
+    buf.put_u8(b'c');
+    write_body(buf, |_| Ok::<(), io::Error>(())).unwrap();
+}
+
+#[inline]
+pub fn copy_fail(message: &str, buf: &mut BytesMut) -> io::Result<()> {
+    buf.put_u8(b'f');
+    write_body(buf, |buf| write_cstr(message.as_bytes(), buf))
+}
+
+#[inline]
+pub fn describe(variant: u8, name: &str, buf: &mut BytesMut) -> io::Result<()> {
+    buf.put_u8(b'D');
+    write_body(buf, |buf| {
+        buf.put_u8(variant);
+        write_cstr(name.as_bytes(), buf)
+    })
+}
+
+#[inline]
+pub fn execute(portal: &str, max_rows: i32, buf: &mut BytesMut) -> io::Result<()> {
+    buf.put_u8(b'E');
+    write_body(buf, |buf| {
+        write_cstr(portal.as_bytes(), buf)?;
+        buf.put_i32(max_rows);
+        Ok(())
+    })
+}
+
+#[inline]
+pub fn parse<I>(name: &str, query: &str, param_types: I, buf: &mut BytesMut) -> io::Result<()>
+where
+    I: IntoIterator<Item = Oid>,
+{
+    buf.put_u8(b'P');
+    write_body(buf, |buf| {
+        write_cstr(name.as_bytes(), buf)?;
+        write_cstr(query.as_bytes(), buf)?;
+        write_counted(
+            param_types,
+            |t, buf| {
+                buf.put_u32(t);
+                Ok::<_, io::Error>(())
+            },
+            buf,
+        )?;
+        Ok(())
+    })
+}
+
+#[inline]
+pub fn password_message(password: &[u8], buf: &mut BytesMut) -> io::Result<()> {
+    buf.put_u8(b'p');
+    write_body(buf, |buf| write_cstr(password, buf))
+}
+
+#[inline]
+pub fn query(query: &str, buf: &mut BytesMut) -> io::Result<()> {
+    buf.put_u8(b'Q');
+    write_body(buf, |buf| write_cstr(query.as_bytes(), buf))
+}
+
+#[inline]
+pub fn sasl_initial_response(mechanism: &str, data: &[u8], buf: &mut BytesMut) -> io::Result<()> {
+    buf.put_u8(b'p');
+    write_body(buf, |buf| {
+        write_cstr(mechanism.as_bytes(), buf)?;
+        let len = i32::from_usize(data.len())?;
+        buf.put_i32(len);
+        buf.put_slice(data);
+        Ok(())
+    })
+}
+
+#[inline]
+pub fn sasl_response(data: &[u8], buf: &mut BytesMut) -> io::Result<()> {
+    buf.put_u8(b'p');
+    write_body(buf, |buf| {
+        buf.put_slice(data);
+        Ok(())
+    })
+}
+
+#[inline]
+pub fn ssl_request(buf: &mut BytesMut) {
+    write_body(buf, |buf| {
+        buf.put_i32(80_877_103);
+        Ok::<_, io::Error>(())
+    })
+    .unwrap();
+}
+
+#[inline]
+pub fn startup_message<'a, I>(parameters: I, buf: &mut BytesMut) -> io::Result<()>
+where
+    I: IntoIterator<Item = (&'a str, &'a str)>,
+{
+    write_body(buf, |buf| {
+        // postgres protocol version 3.0(196608) in bigger-endian
+        buf.put_i32(0x00_03_00_00);
+        for (key, value) in parameters {
+            write_cstr(key.as_bytes(), buf)?;
+            write_cstr(value.as_bytes(), buf)?;
+        }
+        buf.put_u8(0);
+        Ok(())
+    })
+}
+
+#[inline]
+pub fn sync(buf: &mut BytesMut) {
+    buf.put_u8(b'S');
+    write_body(buf, |_| Ok::<(), io::Error>(())).unwrap();
+}
+
+#[inline]
+pub fn terminate(buf: &mut BytesMut) {
+    buf.put_u8(b'X');
+    write_body(buf, |_| Ok::<(), io::Error>(())).unwrap();
+}
+
+#[inline]
+fn write_cstr(s: &[u8], buf: &mut BytesMut) -> Result<(), io::Error> {
+    if s.contains(&0) {
+        return Err(io::Error::new(
+            io::ErrorKind::InvalidInput,
+            "string contains embedded null",
+        ));
+    }
+    buf.put_slice(s);
+    buf.put_u8(0);
+    Ok(())
+}

libs/proxy/postgres-protocol2/src/message/mod.rs

@@ -0,0 +1,8 @@
+//! Postgres message protocol support.
+//!
+//! See [Postgres's documentation][docs] for more information on message flow.
+//!
+//! [docs]: https://www.postgresql.org/docs/9.5/static/protocol-flow.html
+
+pub mod backend;
+pub mod frontend;