haesli/amqp_transport/src/connection.rs
2022-03-04 23:05:50 +01:00

644 lines
21 KiB
Rust

use crate::{
error::{ConException, ProtocolError, Result, TransError},
frame,
frame::{parse_content_header, Frame, FrameType},
methods, sasl,
};
use amqp_core::{
amqp_todo,
connection::{
Channel, ChannelInner, ChannelNum, ConEventReceiver, ConEventSender, Connection,
ConnectionEvent, ConnectionId, ContentHeader,
},
message::{MessageId, RawMessage, RoutingInformation},
methods::{
BasicPublish, ChannelClose, ChannelCloseOk, ChannelOpenOk, ConnectionClose,
ConnectionCloseOk, ConnectionOpen, ConnectionOpenOk, ConnectionStart, ConnectionStartOk,
ConnectionTune, ConnectionTuneOk, FieldValue, Method, ReplyCode, ReplyText, Table,
},
GlobalData,
};
use anyhow::{anyhow, Context};
use bytes::Bytes;
use smallvec::SmallVec;
use std::{
cmp::Ordering, collections::HashMap, net::SocketAddr, pin::Pin, sync::Arc, time::Duration,
};
use tokio::{
io::{AsyncReadExt, AsyncWriteExt},
net::TcpStream,
select, time,
};
use tracing::{debug, error, info, trace, warn};
fn ensure_conn(condition: bool) -> Result<()> {
if condition {
Ok(())
} else {
Err(ConException::Todo.into())
}
}
const FRAME_SIZE_MIN_MAX: usize = 4096;
const CHANNEL_MAX: u16 = 0;
const FRAME_SIZE_MAX: u32 = 0;
const HEARTBEAT_DELAY: u16 = 0;
const BASIC_CLASS_ID: u16 = 60;
pub struct TransportChannel {
/// A handle to the global channel representation. Used to remove the channel when it's dropped
global_chan: Channel,
/// The current status of the channel, whether it has sent a method that expects a body
status: ChannelStatus,
}
pub struct TransportConnection {
id: ConnectionId,
stream: TcpStream,
max_frame_size: usize,
heartbeat_delay: u16,
channel_max: u16,
/// When the next heartbeat expires
next_timeout: Pin<Box<time::Sleep>>,
channels: HashMap<ChannelNum, TransportChannel>,
global_con: Connection,
global_data: GlobalData,
/// Only here to forward to other futures so they can send events
event_sender: ConEventSender,
/// To receive events from other futures
event_receiver: ConEventReceiver,
}
const DEFAULT_TIMEOUT: Duration = Duration::from_secs(30);
enum ChannelStatus {
Default,
NeedHeader(u16, Box<Method>),
NeedsBody(Box<Method>, ContentHeader, SmallVec<[Bytes; 1]>),
}
impl ChannelStatus {
fn take(&mut self) -> Self {
std::mem::replace(self, Self::Default)
}
}
impl TransportConnection {
pub fn new(
id: ConnectionId,
stream: TcpStream,
global_con: Connection,
global_data: GlobalData,
method_queue_send: ConEventSender,
method_queue_recv: ConEventReceiver,
) -> Self {
Self {
id,
stream,
max_frame_size: FRAME_SIZE_MIN_MAX,
heartbeat_delay: HEARTBEAT_DELAY,
channel_max: CHANNEL_MAX,
next_timeout: Box::pin(time::sleep(DEFAULT_TIMEOUT)),
global_con,
channels: HashMap::with_capacity(4),
global_data,
event_sender: method_queue_send,
event_receiver: method_queue_recv,
}
}
pub async fn start_connection_processing(mut self) {
let process_result = self.process_connection().await;
match process_result {
Ok(()) => {}
Err(TransError::Protocol(ProtocolError::GracefullyClosed)) => {
/* do nothing, remove below */
}
Err(TransError::Protocol(ProtocolError::ConException(ex))) => {
warn!(%ex, "Connection exception occurred. This indicates a faulty client.");
let close_result = self.close(ex.reply_code(), ex.reply_text()).await;
match close_result {
Ok(()) => {}
Err(err) => {
error!(%ex, %err, "Failed to close connection after ConnectionException");
}
}
}
Err(err) => error!(%err, "Error during processing of connection"),
}
// global connection is closed on drop
}
pub async fn process_connection(&mut self) -> Result<()> {
self.negotiate_version().await?;
self.start().await?;
self.tune().await?;
self.open().await?;
info!("Connection is ready for usage!");
self.main_loop().await
}
async fn send_method_content(
&mut self,
channel: ChannelNum,
method: &Method,
_header: ContentHeader,
_body: SmallVec<[Bytes; 1]>,
) -> Result<()> {
self.send_method(channel, method).await?;
amqp_todo!()
}
async fn send_method(&mut self, channel: ChannelNum, method: &Method) -> Result<()> {
trace!(%channel, ?method, "Sending method");
let mut payload = Vec::with_capacity(64);
methods::write::write_method(method, &mut payload)?;
frame::write_frame(
&Frame {
kind: FrameType::Method,
channel,
payload: payload.into(),
},
&mut self.stream,
)
.await
}
async fn recv_method(&mut self) -> Result<Method> {
let start_ok_frame = frame::read_frame(&mut self.stream, self.max_frame_size).await?;
ensure_conn(start_ok_frame.kind == FrameType::Method)?;
let method = methods::parse_method(&start_ok_frame.payload)?;
Ok(method)
}
async fn start(&mut self) -> Result<()> {
let start_method = Method::ConnectionStart(ConnectionStart {
version_major: 0,
version_minor: 9,
server_properties: server_properties(
self.stream
.local_addr()
.context("failed to get local_addr")?,
),
mechanisms: "PLAIN".into(),
locales: "en_US".into(),
});
debug!(?start_method, "Sending Start method");
self.send_method(ChannelNum::zero(), &start_method).await?;
let start_ok = self.recv_method().await?;
debug!(?start_ok, "Received Start-Ok");
if let Method::ConnectionStartOk(ConnectionStartOk {
mechanism,
locale,
response,
..
}) = start_ok
{
ensure_conn(mechanism == "PLAIN")?;
ensure_conn(locale == "en_US")?;
let plain_user = sasl::parse_sasl_plain_response(&response)?;
info!(username = %plain_user.authentication_identity, "SASL Authentication successful");
} else {
return Err(ConException::Todo.into());
}
Ok(())
}
async fn tune(&mut self) -> Result<()> {
let tune_method = Method::ConnectionTune(ConnectionTune {
channel_max: CHANNEL_MAX,
frame_max: FRAME_SIZE_MAX,
heartbeat: HEARTBEAT_DELAY,
});
debug!("Sending Tune method");
self.send_method(ChannelNum::zero(), &tune_method).await?;
let tune_ok = self.recv_method().await?;
debug!(?tune_ok, "Received Tune-Ok method");
if let Method::ConnectionTuneOk(ConnectionTuneOk {
channel_max,
frame_max,
heartbeat,
}) = tune_ok
{
self.channel_max = channel_max;
self.max_frame_size = usize::try_from(frame_max).unwrap();
self.heartbeat_delay = heartbeat;
self.reset_timeout();
}
Ok(())
}
async fn open(&mut self) -> Result<()> {
let open = self.recv_method().await?;
debug!(?open, "Received Open method");
if let Method::ConnectionOpen(ConnectionOpen { virtual_host, .. }) = open {
ensure_conn(virtual_host == "/")?;
}
self.send_method(
ChannelNum::zero(),
&Method::ConnectionOpenOk(ConnectionOpenOk {
reserved_1: "".to_owned(),
}),
)
.await?;
Ok(())
}
async fn main_loop(&mut self) -> Result<()> {
loop {
select! {
frame = frame::read_frame(&mut self.stream, self.max_frame_size) => {
let frame = frame?;
self.handle_frame(frame).await?;
}
queued_method = self.event_receiver.recv() => {
match queued_method {
Some(ConnectionEvent::Method(channel, method)) => self.send_method(channel, &method).await?,
Some(ConnectionEvent::MethodContent(channel, method, header, body)) => self.send_method_content(channel, &method, header, body).await?,
Some(ConnectionEvent::Shutdown) => return self.close(0, "".to_owned()).await,
None => {}
}
}
}
}
}
async fn handle_frame(&mut self, frame: Frame) -> Result<()> {
let channel = frame.channel;
self.reset_timeout();
let result = match frame.kind {
FrameType::Method => self.dispatch_method(frame).await,
FrameType::Heartbeat => {
Ok(()) /* Nothing here, just the `reset_timeout` above */
}
FrameType::Header => self.dispatch_header(frame),
FrameType::Body => self.dispatch_body(frame),
};
match result {
Ok(()) => Ok(()),
Err(TransError::Protocol(ProtocolError::ChannelException(ex))) => {
warn!(%ex, "Channel exception occurred");
self.send_method(
channel,
&Method::ChannelClose(ChannelClose {
reply_code: ex.reply_code(),
reply_text: ex.reply_text(),
class_id: 0, // todo: do this
method_id: 0,
}),
)
.await?;
drop(self.channels.remove(&channel));
Ok(())
}
Err(other_err) => Err(other_err),
}
}
async fn dispatch_method(&mut self, frame: Frame) -> Result<()> {
let method = methods::parse_method(&frame.payload)?;
debug!(?method, "Received method");
// Sending a method implicitly cancels the content frames that might be ongoing
self.channels
.get_mut(&frame.channel)
.map(|channel| channel.status.take());
match method {
Method::ConnectionClose(ConnectionClose {
reply_code,
reply_text,
class_id,
method_id,
}) => {
info!(%reply_code, %reply_text, %class_id, %method_id, "Closing connection");
self.send_method(
ChannelNum::zero(),
&Method::ConnectionCloseOk(ConnectionCloseOk),
)
.await?;
return Err(ProtocolError::GracefullyClosed.into());
}
Method::ChannelOpen { .. } => self.channel_open(frame.channel).await?,
Method::ChannelClose { .. } => self.channel_close(frame.channel, method).await?,
Method::BasicPublish { .. } => match self.channels.get_mut(&frame.channel) {
Some(channel) => {
channel.status = ChannelStatus::NeedHeader(BASIC_CLASS_ID, Box::new(method));
}
None => return Err(ConException::Todo.into()),
},
_ => {
let channel_handle = self
.channels
.get(&frame.channel)
.ok_or(ConException::Todo)?
.global_chan
.clone();
// call into amqp_messaging to handle the method
// it returns the response method that we are supposed to send
// maybe this might become an `Option` in the future
let return_method =
amqp_messaging::methods::handle_method(channel_handle, method).await?;
self.send_method(frame.channel, &return_method).await?;
}
}
Ok(())
}
fn dispatch_header(&mut self, frame: Frame) -> Result<()> {
self.channels
.get_mut(&frame.channel)
.ok_or_else(|| ConException::Todo.into())
.and_then(|channel| match channel.status.take() {
ChannelStatus::Default => {
warn!(channel = %frame.channel, "unexpected header");
Err(ConException::UnexpectedFrame.into())
}
ChannelStatus::NeedHeader(class_id, method) => {
let header = parse_content_header(&frame.payload)?;
ensure_conn(header.class_id == class_id)?;
channel.status = ChannelStatus::NeedsBody(method, header, SmallVec::new());
Ok(())
}
ChannelStatus::NeedsBody(_, _, _) => {
warn!(channel = %frame.channel, "already got header");
Err(ConException::UnexpectedFrame.into())
}
})
}
fn dispatch_body(&mut self, frame: Frame) -> Result<()> {
let channel = self
.channels
.get_mut(&frame.channel)
.ok_or(ConException::Todo)?;
match channel.status.take() {
ChannelStatus::Default => {
warn!(channel = %frame.channel, "unexpected body");
Err(ConException::UnexpectedFrame.into())
}
ChannelStatus::NeedHeader(_, _) => {
warn!(channel = %frame.channel, "unexpected body");
Err(ConException::UnexpectedFrame.into())
}
ChannelStatus::NeedsBody(method, header, mut vec) => {
vec.push(frame.payload);
match vec
.iter()
.map(Bytes::len)
.sum::<usize>()
.cmp(&usize::try_from(header.body_size).unwrap())
{
Ordering::Equal => {
self.process_method_with_body(*method, header, vec, frame.channel)
}
Ordering::Greater => Err(ConException::Todo.into()),
Ordering::Less => Ok(()), // wait for next body
}
}
}
}
fn process_method_with_body(
&mut self,
method: Method,
header: ContentHeader,
payloads: SmallVec<[Bytes; 1]>,
channel: ChannelNum,
) -> Result<()> {
// The only method with content that is sent to the server is Basic.Publish.
ensure_conn(header.class_id == BASIC_CLASS_ID)?;
if let Method::BasicPublish(BasicPublish {
exchange,
routing_key,
mandatory,
immediate,
..
}) = method
{
let message = RawMessage {
id: MessageId::random(),
header,
routing: RoutingInformation {
exchange,
routing_key,
mandatory,
immediate,
},
content: payloads,
};
let message = Arc::new(message);
let channel = self.channels.get(&channel).ok_or(ConException::Todo)?;
// Spawn the handler for the publish. The connection task goes back to handling
// just the connection.
tokio::spawn(amqp_messaging::methods::handle_basic_publish(
channel.global_chan.clone(),
message,
));
Ok(())
} else {
Err(ConException::Todo.into())
}
}
async fn channel_open(&mut self, channel_num: ChannelNum) -> Result<()> {
let id = rand::random();
let channel_handle = ChannelInner::new(
id,
channel_num,
self.global_con.clone(),
self.global_data.clone(),
self.event_sender.clone(),
);
let channel = TransportChannel {
global_chan: channel_handle.clone(),
status: ChannelStatus::Default,
};
let prev = self.channels.insert(channel_num, channel);
if let Some(prev) = prev {
self.channels.insert(channel_num, prev); // restore previous state
return Err(ConException::ChannelError.into());
}
{
let mut global_data = self.global_data.lock();
global_data.channels.insert(id, channel_handle.clone());
global_data
.connections
.get_mut(&self.id)
.unwrap()
.channels
.lock()
.insert(channel_num, channel_handle);
}
info!(%channel_num, "Opened new channel");
self.send_method(
channel_num,
&Method::ChannelOpenOk(ChannelOpenOk {
reserved_1: Vec::new(),
}),
)
.await?;
Ok(())
}
async fn channel_close(&mut self, channel_id: ChannelNum, method: Method) -> Result<()> {
if let Method::ChannelClose(ChannelClose {
reply_code: code,
reply_text: reason,
..
}) = method
{
info!(%code, %reason, "Closing channel");
if let Some(channel) = self.channels.remove(&channel_id) {
drop(channel);
self.send_method(channel_id, &Method::ChannelCloseOk(ChannelCloseOk))
.await?;
} else {
return Err(ConException::Todo.into());
}
} else {
unreachable!()
}
Ok(())
}
fn reset_timeout(&mut self) {
if self.heartbeat_delay != 0 {
let next = Duration::from_secs(u64::from(self.heartbeat_delay / 2));
self.next_timeout = Box::pin(time::sleep(next));
}
}
async fn negotiate_version(&mut self) -> Result<()> {
const HEADER_SIZE: usize = 8;
const SUPPORTED_PROTOCOL_VERSION: &[u8] = &[0, 9, 1];
const AMQP_PROTOCOL: &[u8] = b"AMQP";
const OWN_PROTOCOL_HEADER: &[u8] = b"AMQP\0\0\x09\x01";
debug!("Negotiating version");
let mut read_header_buf = [0; HEADER_SIZE];
self.stream
.read_exact(&mut read_header_buf)
.await
.context("read protocol header")?;
debug!(received_header = ?read_header_buf,"Received protocol header");
let protocol = &read_header_buf[0..4];
let version = &read_header_buf[5..8];
if protocol != AMQP_PROTOCOL {
self.stream
.write_all(OWN_PROTOCOL_HEADER)
.await
.context("write protocol header")?;
debug!(?protocol, "Version negotiation failed");
return Err(ProtocolError::ProtocolNegotiationFailed.into());
}
if &read_header_buf[0..5] == b"AMQP\0" && version == SUPPORTED_PROTOCOL_VERSION {
debug!(?version, "Version negotiation successful");
Ok(())
} else {
self.stream
.write_all(OWN_PROTOCOL_HEADER)
.await
.context("write protocol header")?;
debug!(?version, expected_version = ?SUPPORTED_PROTOCOL_VERSION, "Version negotiation failed");
Err(ProtocolError::ProtocolNegotiationFailed.into())
}
}
async fn close(&mut self, reply_code: ReplyCode, reply_text: ReplyText) -> Result<()> {
self.send_method(
ChannelNum::zero(),
&Method::ConnectionClose(ConnectionClose {
reply_code,
reply_text,
class_id: 0, // todo: do this
method_id: 0,
}),
)
.await?;
match self.recv_method().await {
Ok(Method::ConnectionCloseOk(_)) => Ok(()),
Ok(method) => {
return Err(TransError::Other(anyhow!(
"Received wrong method after closing, method: {method:?}"
)));
}
Err(err) => {
return Err(TransError::Other(anyhow!(
"Failed to receive Connection.CloseOk method after closing, err: {err}"
)));
}
}
}
}
impl Drop for TransportConnection {
fn drop(&mut self) {
self.global_con.close();
}
}
impl Drop for TransportChannel {
fn drop(&mut self) {
self.global_chan.close();
}
}
fn server_properties(host: SocketAddr) -> Table {
fn ls(str: &str) -> FieldValue {
FieldValue::LongString(str.into())
}
let host_str = host.ip().to_string();
HashMap::from([
("host".to_owned(), ls(&host_str)),
("product".to_owned(), ls("no name yet")),
("version".to_owned(), ls("0.1.0")),
("platform".to_owned(), ls("microsoft linux")),
("copyright".to_owned(), ls("MIT")),
("information".to_owned(), ls("hello reader")),
("uwu".to_owned(), ls("owo")),
])
}