wip: split garage_api into garage_api_{common,s3,k2v,admin}

src/api/common/Cargo.toml

@@ -0,0 +1,73 @@
+[package]
+name = "garage_api_common"
+version = "1.0.1"
+authors = ["Alex Auvolat <alex@adnab.me>"]
+edition = "2018"
+license = "AGPL-3.0"
+description = "S3 API server crate for the Garage object store"
+repository = "https://git.deuxfleurs.fr/Deuxfleurs/garage"
+readme = "../../README.md"
+
+[lib]
+path = "lib.rs"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+garage_model.workspace = true
+garage_table.workspace = true
+garage_block.workspace = true
+garage_net.workspace = true
+garage_util.workspace = true
+garage_rpc.workspace = true
+
+aes-gcm.workspace = true
+argon2.workspace = true
+async-compression.workspace = true
+async-trait.workspace = true
+base64.workspace = true
+bytes.workspace = true
+chrono.workspace = true
+crc32fast.workspace = true
+crc32c.workspace = true
+crypto-common.workspace = true
+err-derive.workspace = true
+hex.workspace = true
+hmac.workspace = true
+idna.workspace = true
+tracing.workspace = true
+md-5.workspace = true
+nom.workspace = true
+pin-project.workspace = true
+sha1.workspace = true
+sha2.workspace = true
+
+futures.workspace = true
+futures-util.workspace = true
+tokio.workspace = true
+tokio-stream.workspace = true
+tokio-util.workspace = true
+
+form_urlencoded.workspace = true
+http.workspace = true
+httpdate.workspace = true
+http-range.workspace = true
+http-body-util.workspace = true
+hyper = { workspace = true, default-features = false, features = ["server", "http1"] }
+hyper-util.workspace = true
+multer.workspace = true
+percent-encoding.workspace = true
+roxmltree.workspace = true
+url.workspace = true
+
+serde.workspace = true
+serde_bytes.workspace = true
+serde_json.workspace = true
+quick-xml.workspace = true
+
+opentelemetry.workspace = true
+opentelemetry-prometheus = { workspace = true, optional = true }
+prometheus = { workspace = true, optional = true }
+
+[features]
+metrics = [ "opentelemetry-prometheus", "prometheus" ]

src/api/common/common_error.rs

@@ -0,0 +1,217 @@
+use std::convert::TryFrom;
+
+use err_derive::Error;
+use hyper::StatusCode;
+
+use garage_util::error::Error as GarageError;
+
+use garage_model::helper::error::Error as HelperError;
+
+/// Errors of this crate
+#[derive(Debug, Error)]
+pub enum CommonError {
+	// ---- INTERNAL ERRORS ----
+	/// Error related to deeper parts of Garage
+	#[error(display = "Internal error: {}", _0)]
+	InternalError(#[error(source)] GarageError),
+
+	/// Error related to Hyper
+	#[error(display = "Internal error (Hyper error): {}", _0)]
+	Hyper(#[error(source)] hyper::Error),
+
+	/// Error related to HTTP
+	#[error(display = "Internal error (HTTP error): {}", _0)]
+	Http(#[error(source)] http::Error),
+
+	// ---- GENERIC CLIENT ERRORS ----
+	/// Proper authentication was not provided
+	#[error(display = "Forbidden: {}", _0)]
+	Forbidden(String),
+
+	/// Generic bad request response with custom message
+	#[error(display = "Bad request: {}", _0)]
+	BadRequest(String),
+
+	/// The client sent a header with invalid value
+	#[error(display = "Invalid header value: {}", _0)]
+	InvalidHeader(#[error(source)] hyper::header::ToStrError),
+
+	// ---- SPECIFIC ERROR CONDITIONS ----
+	// These have to be error codes referenced in the S3 spec here:
+	// https://docs.aws.amazon.com/AmazonS3/latest/API/ErrorResponses.html#ErrorCodeList
+	/// The bucket requested don't exists
+	#[error(display = "Bucket not found: {}", _0)]
+	NoSuchBucket(String),
+
+	/// Tried to create a bucket that already exist
+	#[error(display = "Bucket already exists")]
+	BucketAlreadyExists,
+
+	/// Tried to delete a non-empty bucket
+	#[error(display = "Tried to delete a non-empty bucket")]
+	BucketNotEmpty,
+
+	// Category: bad request
+	/// Bucket name is not valid according to AWS S3 specs
+	#[error(display = "Invalid bucket name: {}", _0)]
+	InvalidBucketName(String),
+}
+
+impl CommonError {
+	pub fn http_status_code(&self) -> StatusCode {
+		match self {
+			CommonError::InternalError(
+				GarageError::Timeout | GarageError::RemoteError(_) | GarageError::Quorum(..),
+			) => StatusCode::SERVICE_UNAVAILABLE,
+			CommonError::InternalError(_) | CommonError::Hyper(_) | CommonError::Http(_) => {
+				StatusCode::INTERNAL_SERVER_ERROR
+			}
+			CommonError::BadRequest(_) => StatusCode::BAD_REQUEST,
+			CommonError::Forbidden(_) => StatusCode::FORBIDDEN,
+			CommonError::NoSuchBucket(_) => StatusCode::NOT_FOUND,
+			CommonError::BucketNotEmpty | CommonError::BucketAlreadyExists => StatusCode::CONFLICT,
+			CommonError::InvalidBucketName(_) | CommonError::InvalidHeader(_) => {
+				StatusCode::BAD_REQUEST
+			}
+		}
+	}
+
+	pub fn aws_code(&self) -> &'static str {
+		match self {
+			CommonError::Forbidden(_) => "AccessDenied",
+			CommonError::InternalError(
+				GarageError::Timeout | GarageError::RemoteError(_) | GarageError::Quorum(..),
+			) => "ServiceUnavailable",
+			CommonError::InternalError(_) | CommonError::Hyper(_) | CommonError::Http(_) => {
+				"InternalError"
+			}
+			CommonError::BadRequest(_) => "InvalidRequest",
+			CommonError::NoSuchBucket(_) => "NoSuchBucket",
+			CommonError::BucketAlreadyExists => "BucketAlreadyExists",
+			CommonError::BucketNotEmpty => "BucketNotEmpty",
+			CommonError::InvalidBucketName(_) => "InvalidBucketName",
+			CommonError::InvalidHeader(_) => "InvalidHeaderValue",
+		}
+	}
+
+	pub fn bad_request<M: ToString>(msg: M) -> Self {
+		CommonError::BadRequest(msg.to_string())
+	}
+}
+
+impl TryFrom<HelperError> for CommonError {
+	type Error = HelperError;
+
+	fn try_from(err: HelperError) -> Result<Self, HelperError> {
+		match err {
+			HelperError::Internal(i) => Ok(Self::InternalError(i)),
+			HelperError::BadRequest(b) => Ok(Self::BadRequest(b)),
+			HelperError::InvalidBucketName(n) => Ok(Self::InvalidBucketName(n)),
+			HelperError::NoSuchBucket(n) => Ok(Self::NoSuchBucket(n)),
+			e => Err(e),
+		}
+	}
+}
+
+/// This function converts HelperErrors into CommonErrors,
+/// for variants that exist in CommonError.
+/// This is used for helper functions that might return InvalidBucketName
+/// or NoSuchBucket for instance, and we want to pass that error
+/// up to our caller.
+pub fn pass_helper_error(err: HelperError) -> CommonError {
+	match CommonError::try_from(err) {
+		Ok(e) => e,
+		Err(e) => panic!("Helper error `{}` should hot have happenned here", e),
+	}
+}
+
+pub fn helper_error_as_internal(err: HelperError) -> CommonError {
+	match err {
+		HelperError::Internal(e) => CommonError::InternalError(e),
+		e => CommonError::InternalError(GarageError::Message(e.to_string())),
+	}
+}
+
+pub trait CommonErrorDerivative: From<CommonError> {
+	fn internal_error<M: ToString>(msg: M) -> Self {
+		Self::from(CommonError::InternalError(GarageError::Message(
+			msg.to_string(),
+		)))
+	}
+
+	fn bad_request<M: ToString>(msg: M) -> Self {
+		Self::from(CommonError::BadRequest(msg.to_string()))
+	}
+
+	fn forbidden<M: ToString>(msg: M) -> Self {
+		Self::from(CommonError::Forbidden(msg.to_string()))
+	}
+}
+
+/// Trait to map error to the Bad Request error code
+pub trait OkOrBadRequest {
+	type S;
+	fn ok_or_bad_request<M: AsRef<str>>(self, reason: M) -> Result<Self::S, CommonError>;
+}
+
+impl<T, E> OkOrBadRequest for Result<T, E>
+where
+	E: std::fmt::Display,
+{
+	type S = T;
+	fn ok_or_bad_request<M: AsRef<str>>(self, reason: M) -> Result<T, CommonError> {
+		match self {
+			Ok(x) => Ok(x),
+			Err(e) => Err(CommonError::BadRequest(format!(
+				"{}: {}",
+				reason.as_ref(),
+				e
+			))),
+		}
+	}
+}
+
+impl<T> OkOrBadRequest for Option<T> {
+	type S = T;
+	fn ok_or_bad_request<M: AsRef<str>>(self, reason: M) -> Result<T, CommonError> {
+		match self {
+			Some(x) => Ok(x),
+			None => Err(CommonError::BadRequest(reason.as_ref().to_string())),
+		}
+	}
+}
+
+/// Trait to map an error to an Internal Error code
+pub trait OkOrInternalError {
+	type S;
+	fn ok_or_internal_error<M: AsRef<str>>(self, reason: M) -> Result<Self::S, CommonError>;
+}
+
+impl<T, E> OkOrInternalError for Result<T, E>
+where
+	E: std::fmt::Display,
+{
+	type S = T;
+	fn ok_or_internal_error<M: AsRef<str>>(self, reason: M) -> Result<T, CommonError> {
+		match self {
+			Ok(x) => Ok(x),
+			Err(e) => Err(CommonError::InternalError(GarageError::Message(format!(
+				"{}: {}",
+				reason.as_ref(),
+				e
+			)))),
+		}
+	}
+}
+
+impl<T> OkOrInternalError for Option<T> {
+	type S = T;
+	fn ok_or_internal_error<M: AsRef<str>>(self, reason: M) -> Result<T, CommonError> {
+		match self {
+			Some(x) => Ok(x),
+			None => Err(CommonError::InternalError(GarageError::Message(
+				reason.as_ref().to_string(),
+			))),
+		}
+	}
+}

src/api/common/encoding.rs

@@ -0,0 +1,22 @@
+//! Module containing various helpers for encoding
+
+/// Encode &str for use in a URI
+pub fn uri_encode(string: &str, encode_slash: bool) -> String {
+	let mut result = String::with_capacity(string.len() * 2);
+	for c in string.chars() {
+		match c {
+			'a'..='z' | 'A'..='Z' | '0'..='9' | '_' | '-' | '~' | '.' => result.push(c),
+			'/' if encode_slash => result.push_str("%2F"),
+			'/' if !encode_slash => result.push('/'),
+			_ => {
+				result.push_str(
+					&format!("{}", c)
+						.bytes()
+						.map(|b| format!("%{:02X}", b))
+						.collect::<String>(),
+				);
+			}
+		}
+	}
+	result
+}

src/api/common/generic_server.rs

@@ -0,0 +1,378 @@
+use std::convert::Infallible;
+use std::fs::{self, Permissions};
+use std::os::unix::fs::PermissionsExt;
+use std::sync::Arc;
+use std::time::Duration;
+
+use async_trait::async_trait;
+
+use futures::future::Future;
+use futures::stream::{futures_unordered::FuturesUnordered, StreamExt};
+
+use http_body_util::BodyExt;
+use hyper::header::HeaderValue;
+use hyper::server::conn::http1;
+use hyper::service::service_fn;
+use hyper::{body::Incoming as IncomingBody, Request, Response};
+use hyper::{HeaderMap, StatusCode};
+use hyper_util::rt::TokioIo;
+
+use tokio::io::{AsyncRead, AsyncWrite};
+use tokio::net::{TcpListener, TcpStream, UnixListener, UnixStream};
+use tokio::sync::watch;
+use tokio::time::{sleep_until, Instant};
+
+use opentelemetry::{
+	global,
+	metrics::{Counter, ValueRecorder},
+	trace::{FutureExt, SpanRef, TraceContextExt, Tracer},
+	Context, KeyValue,
+};
+
+use garage_util::error::Error as GarageError;
+use garage_util::forwarded_headers;
+use garage_util::metrics::{gen_trace_id, RecordDuration};
+use garage_util::socket_address::UnixOrTCPSocketAddress;
+
+use crate::helpers::{BoxBody, ErrorBody};
+
+pub trait ApiEndpoint: Send + Sync + 'static {
+	fn name(&self) -> &'static str;
+	fn add_span_attributes(&self, span: SpanRef<'_>);
+}
+
+pub trait ApiError: std::error::Error + Send + Sync + 'static {
+	fn http_status_code(&self) -> StatusCode;
+	fn add_http_headers(&self, header_map: &mut HeaderMap<HeaderValue>);
+	fn http_body(&self, garage_region: &str, path: &str) -> ErrorBody;
+}
+
+#[async_trait]
+pub trait ApiHandler: Send + Sync + 'static {
+	const API_NAME: &'static str;
+	const API_NAME_DISPLAY: &'static str;
+
+	type Endpoint: ApiEndpoint;
+	type Error: ApiError;
+
+	fn parse_endpoint(&self, r: &Request<IncomingBody>) -> Result<Self::Endpoint, Self::Error>;
+	async fn handle(
+		&self,
+		req: Request<IncomingBody>,
+		endpoint: Self::Endpoint,
+	) -> Result<Response<BoxBody<Self::Error>>, Self::Error>;
+}
+
+pub struct ApiServer<A: ApiHandler> {
+	region: String,
+	api_handler: A,
+
+	// Metrics
+	request_counter: Counter<u64>,
+	error_counter: Counter<u64>,
+	request_duration: ValueRecorder<f64>,
+}
+
+impl<A: ApiHandler> ApiServer<A> {
+	pub fn new(region: String, api_handler: A) -> Arc<Self> {
+		let meter = global::meter("garage/api");
+		Arc::new(Self {
+			region,
+			api_handler,
+			request_counter: meter
+				.u64_counter(format!("api.{}.request_counter", A::API_NAME))
+				.with_description(format!(
+					"Number of API calls to the various {} API endpoints",
+					A::API_NAME_DISPLAY
+				))
+				.init(),
+			error_counter: meter
+				.u64_counter(format!("api.{}.error_counter", A::API_NAME))
+				.with_description(format!(
+					"Number of API calls to the various {} API endpoints that resulted in errors",
+					A::API_NAME_DISPLAY
+				))
+				.init(),
+			request_duration: meter
+				.f64_value_recorder(format!("api.{}.request_duration", A::API_NAME))
+				.with_description(format!(
+					"Duration of API calls to the various {} API endpoints",
+					A::API_NAME_DISPLAY
+				))
+				.init(),
+		})
+	}
+
+	pub async fn run_server(
+		self: Arc<Self>,
+		bind_addr: UnixOrTCPSocketAddress,
+		unix_bind_addr_mode: Option<u32>,
+		must_exit: watch::Receiver<bool>,
+	) -> Result<(), GarageError> {
+		let server_name = format!("{} API", A::API_NAME_DISPLAY);
+		info!("{} server listening on {}", server_name, bind_addr);
+
+		match bind_addr {
+			UnixOrTCPSocketAddress::TCPSocket(addr) => {
+				let listener = TcpListener::bind(addr).await?;
+
+				let handler = move |request, socketaddr| self.clone().handler(request, socketaddr);
+				server_loop(server_name, listener, handler, must_exit).await
+			}
+			UnixOrTCPSocketAddress::UnixSocket(ref path) => {
+				if path.exists() {
+					fs::remove_file(path)?
+				}
+
+				let listener = UnixListener::bind(path)?;
+				let listener = UnixListenerOn(listener, path.display().to_string());
+
+				fs::set_permissions(
+					path,
+					Permissions::from_mode(unix_bind_addr_mode.unwrap_or(0o222)),
+				)?;
+
+				let handler = move |request, socketaddr| self.clone().handler(request, socketaddr);
+				server_loop(server_name, listener, handler, must_exit).await
+			}
+		}
+	}
+
+	async fn handler(
+		self: Arc<Self>,
+		req: Request<IncomingBody>,
+		addr: String,
+	) -> Result<Response<BoxBody<A::Error>>, http::Error> {
+		let uri = req.uri().clone();
+
+		if let Ok(forwarded_for_ip_addr) =
+			forwarded_headers::handle_forwarded_for_headers(req.headers())
+		{
+			info!(
+				"{} (via {}) {} {}",
+				forwarded_for_ip_addr,
+				addr,
+				req.method(),
+				uri
+			);
+		} else {
+			info!("{} {} {}", addr, req.method(), uri);
+		}
+		debug!("{:?}", req);
+
+		let tracer = opentelemetry::global::tracer("garage");
+		let span = tracer
+			.span_builder(format!("{} API call (unknown)", A::API_NAME_DISPLAY))
+			.with_trace_id(gen_trace_id())
+			.with_attributes(vec![
+				KeyValue::new("method", format!("{}", req.method())),
+				KeyValue::new("uri", req.uri().to_string()),
+			])
+			.start(&tracer);
+
+		let res = self
+			.handler_stage2(req)
+			.with_context(Context::current_with_span(span))
+			.await;
+
+		match res {
+			Ok(x) => {
+				debug!("{} {:?}", x.status(), x.headers());
+				Ok(x)
+			}
+			Err(e) => {
+				let body = e.http_body(&self.region, uri.path());
+				let mut http_error_builder = Response::builder().status(e.http_status_code());
+
+				if let Some(header_map) = http_error_builder.headers_mut() {
+					e.add_http_headers(header_map)
+				}
+
+				let http_error = http_error_builder.body(body)?;
+
+				if e.http_status_code().is_server_error() {
+					warn!("Response: error {}, {}", e.http_status_code(), e);
+				} else {
+					info!("Response: error {}, {}", e.http_status_code(), e);
+				}
+				Ok(http_error
+					.map(|body| BoxBody::new(body.map_err(|_: Infallible| unreachable!()))))
+			}
+		}
+	}
+
+	async fn handler_stage2(
+		&self,
+		req: Request<IncomingBody>,
+	) -> Result<Response<BoxBody<A::Error>>, A::Error> {
+		let endpoint = self.api_handler.parse_endpoint(&req)?;
+		debug!("Endpoint: {}", endpoint.name());
+
+		let current_context = Context::current();
+		let current_span = current_context.span();
+		current_span.update_name::<String>(format!(
+			"{} API {}",
+			A::API_NAME_DISPLAY,
+			endpoint.name()
+		));
+		current_span.set_attribute(KeyValue::new("endpoint", endpoint.name()));
+		endpoint.add_span_attributes(current_span);
+
+		let metrics_tags = &[KeyValue::new("api_endpoint", endpoint.name())];
+
+		let res = self
+			.api_handler
+			.handle(req, endpoint)
+			.record_duration(&self.request_duration, &metrics_tags[..])
+			.await;
+
+		self.request_counter.add(1, &metrics_tags[..]);
+
+		let status_code = match &res {
+			Ok(r) => r.status(),
+			Err(e) => e.http_status_code(),
+		};
+		if status_code.is_client_error() || status_code.is_server_error() {
+			self.error_counter.add(
+				1,
+				&[
+					metrics_tags[0].clone(),
+					KeyValue::new("status_code", status_code.as_str().to_string()),
+				],
+			);
+		}
+
+		res
+	}
+}
+
+// ==== helper functions ====
+
+#[async_trait]
+pub trait Accept: Send + Sync + 'static {
+	type Stream: AsyncRead + AsyncWrite + Send + Sync + 'static;
+	async fn accept(&self) -> std::io::Result<(Self::Stream, String)>;
+}
+
+#[async_trait]
+impl Accept for TcpListener {
+	type Stream = TcpStream;
+	async fn accept(&self) -> std::io::Result<(Self::Stream, String)> {
+		self.accept()
+			.await
+			.map(|(stream, addr)| (stream, addr.to_string()))
+	}
+}
+
+pub struct UnixListenerOn(pub UnixListener, pub String);
+
+#[async_trait]
+impl Accept for UnixListenerOn {
+	type Stream = UnixStream;
+	async fn accept(&self) -> std::io::Result<(Self::Stream, String)> {
+		self.0
+			.accept()
+			.await
+			.map(|(stream, _addr)| (stream, self.1.clone()))
+	}
+}
+
+pub async fn server_loop<A, H, F, E>(
+	server_name: String,
+	listener: A,
+	handler: H,
+	mut must_exit: watch::Receiver<bool>,
+) -> Result<(), GarageError>
+where
+	A: Accept,
+	H: Fn(Request<IncomingBody>, String) -> F + Send + Sync + Clone + 'static,
+	F: Future<Output = Result<Response<BoxBody<E>>, http::Error>> + Send + 'static,
+	E: Send + Sync + std::error::Error + 'static,
+{
+	let (conn_in, mut conn_out) = tokio::sync::mpsc::unbounded_channel();
+	let connection_collector = tokio::spawn({
+		let server_name = server_name.clone();
+		async move {
+			let mut connections = FuturesUnordered::<tokio::task::JoinHandle<()>>::new();
+			loop {
+				let collect_next = async {
+					if connections.is_empty() {
+						futures::future::pending().await
+					} else {
+						connections.next().await
+					}
+				};
+				tokio::select! {
+					result = collect_next => {
+						trace!("{} server: HTTP connection finished: {:?}", server_name, result);
+					}
+					new_fut = conn_out.recv() => {
+						match new_fut {
+							Some(f) => connections.push(f),
+							None => break,
+						}
+					}
+				}
+			}
+			let deadline = Instant::now() + Duration::from_secs(10);
+			while !connections.is_empty() {
+				info!(
+					"{} server: {} connections still open, deadline in {:.2}s",
+					server_name,
+					connections.len(),
+					(deadline - Instant::now()).as_secs_f32(),
+				);
+				tokio::select! {
+					conn_res = connections.next() => {
+						trace!(
+							"{} server: HTTP connection finished: {:?}",
+							server_name,
+							conn_res.unwrap(),
+						);
+					}
+					_ = sleep_until(deadline) => {
+						warn!("{} server: exit deadline reached with {} connections still open, killing them now",
+							server_name,
+							connections.len());
+						for conn in connections.iter() {
+							conn.abort();
+						}
+						for conn in connections {
+							assert!(conn.await.unwrap_err().is_cancelled());
+						}
+						break;
+					}
+				}
+			}
+		}
+	});
+
+	while !*must_exit.borrow() {
+		let (stream, client_addr) = tokio::select! {
+			acc = listener.accept() => acc?,
+			_ = must_exit.changed() => continue,
+		};
+
+		let io = TokioIo::new(stream);
+
+		let handler = handler.clone();
+		let serve = move |req: Request<IncomingBody>| handler(req, client_addr.clone());
+
+		let fut = tokio::task::spawn(async move {
+			let io = Box::pin(io);
+			if let Err(e) = http1::Builder::new()
+				.serve_connection(io, service_fn(serve))
+				.await
+			{
+				debug!("Error handling HTTP connection: {}", e);
+			}
+		});
+		conn_in.send(fut)?;
+	}
+
+	info!("{} server exiting", server_name);
+	drop(conn_in);
+	connection_collector.await?;
+
+	Ok(())
+}

src/api/common/helpers.rs

@@ -0,0 +1,371 @@
+use std::convert::Infallible;
+use std::sync::Arc;
+
+use futures::{Stream, StreamExt, TryStreamExt};
+
+use http_body_util::{BodyExt, Full as FullBody};
+use hyper::{
+	body::{Body, Bytes},
+	Request, Response,
+};
+use idna::domain_to_unicode;
+use serde::{Deserialize, Serialize};
+
+use garage_model::bucket_table::BucketParams;
+use garage_model::garage::Garage;
+use garage_model::key_table::Key;
+use garage_util::data::Uuid;
+use garage_util::error::Error as GarageError;
+
+use crate::common_error::{CommonError as Error, *};
+
+/// What kind of authorization is required to perform a given action
+#[derive(Debug, Clone, PartialEq, Eq)]
+pub enum Authorization {
+	/// No authorization is required
+	None,
+	/// Having Read permission on bucket
+	Read,
+	/// Having Write permission on bucket
+	Write,
+	/// Having Owner permission on bucket
+	Owner,
+}
+
+/// The values which are known for each request related to a bucket
+pub struct ReqCtx {
+	pub garage: Arc<Garage>,
+	pub bucket_id: Uuid,
+	pub bucket_name: String,
+	pub bucket_params: BucketParams,
+	pub api_key: Key,
+}
+
+/// Host to bucket
+///
+/// Convert a host, like "bucket.garage-site.tld" to the corresponding bucket "bucket",
+/// considering that ".garage-site.tld" is the "root domain". For domains not matching
+/// the provided root domain, no bucket is returned
+/// This behavior has been chosen to follow AWS S3 semantic.
+pub fn host_to_bucket<'a>(host: &'a str, root: &str) -> Option<&'a str> {
+	let root = root.trim_start_matches('.');
+	let label_root = root.chars().filter(|c| c == &'.').count() + 1;
+	let root = root.rsplit('.');
+	let mut host = host.rsplitn(label_root + 1, '.');
+	for root_part in root {
+		let host_part = host.next()?;
+		if root_part != host_part {
+			return None;
+		}
+	}
+	host.next()
+}
+
+/// Extract host from the authority section given by the HTTP host header
+///
+/// The HTTP host contains both a host and a port.
+/// Extracting the port is more complex than just finding the colon (:) symbol due to IPv6
+/// We do not use the collect pattern as there is no way in std rust to collect over a stack allocated value
+/// check here: <https://docs.rs/collect_slice/1.2.0/collect_slice/>
+pub fn authority_to_host(authority: &str) -> Result<String, Error> {
+	let mut iter = authority.chars().enumerate();
+	let (_, first_char) = iter
+		.next()
+		.ok_or_else(|| Error::bad_request("Authority is empty".to_string()))?;
+
+	let split = match first_char {
+		'[' => {
+			let mut iter = iter.skip_while(|(_, c)| c != &']');
+			match iter.next() {
+				Some((_, ']')) => iter.next(),
+				_ => {
+					return Err(Error::bad_request(format!(
+						"Authority {} has an illegal format",
+						authority
+					)))
+				}
+			}
+		}
+		_ => iter.find(|(_, c)| *c == ':'),
+	};
+
+	let authority = match split {
+		Some((i, ':')) => Ok(&authority[..i]),
+		None => Ok(authority),
+		Some((_, _)) => Err(Error::bad_request(format!(
+			"Authority {} has an illegal format",
+			authority
+		))),
+	};
+	authority.map(|h| domain_to_unicode(h).0)
+}
+
+/// Extract the bucket name and the key name from an HTTP path and possibly a bucket provided in
+/// the host header of the request
+///
+/// S3 internally manages only buckets and keys. This function splits
+/// an HTTP path to get the corresponding bucket name and key.
+pub fn parse_bucket_key<'a>(
+	path: &'a str,
+	host_bucket: Option<&'a str>,
+) -> Result<(&'a str, Option<&'a str>), Error> {
+	let path = path.trim_start_matches('/');
+
+	if let Some(bucket) = host_bucket {
+		if !path.is_empty() {
+			return Ok((bucket, Some(path)));
+		} else {
+			return Ok((bucket, None));
+		}
+	}
+
+	let (bucket, key) = match path.find('/') {
+		Some(i) => {
+			let key = &path[i + 1..];
+			if !key.is_empty() {
+				(&path[..i], Some(key))
+			} else {
+				(&path[..i], None)
+			}
+		}
+		None => (path, None),
+	};
+	if bucket.is_empty() {
+		return Err(Error::bad_request("No bucket specified"));
+	}
+	Ok((bucket, key))
+}
+
+const UTF8_BEFORE_LAST_CHAR: char = '\u{10FFFE}';
+
+/// Compute the key after the prefix
+pub fn key_after_prefix(pfx: &str) -> Option<String> {
+	let mut next = pfx.to_string();
+	while !next.is_empty() {
+		let tail = next.pop().unwrap();
+		if tail >= char::MAX {
+			continue;
+		}
+
+		// Circumvent a limitation of RangeFrom that overflow earlier than needed
+		// See: https://doc.rust-lang.org/core/ops/struct.RangeFrom.html
+		let new_tail = if tail == UTF8_BEFORE_LAST_CHAR {
+			char::MAX
+		} else {
+			(tail..).nth(1).unwrap()
+		};
+
+		next.push(new_tail);
+		return Some(next);
+	}
+
+	None
+}
+
+// =============== body helpers =================
+
+pub type EmptyBody = http_body_util::Empty<bytes::Bytes>;
+pub type ErrorBody = FullBody<bytes::Bytes>;
+pub type BoxBody<E> = http_body_util::combinators::BoxBody<bytes::Bytes, E>;
+
+pub fn string_body<E>(s: String) -> BoxBody<E> {
+	bytes_body(bytes::Bytes::from(s.into_bytes()))
+}
+pub fn bytes_body<E>(b: bytes::Bytes) -> BoxBody<E> {
+	BoxBody::new(FullBody::new(b).map_err(|_: Infallible| unreachable!()))
+}
+pub fn empty_body<E>() -> BoxBody<E> {
+	BoxBody::new(http_body_util::Empty::new().map_err(|_: Infallible| unreachable!()))
+}
+pub fn error_body(s: String) -> ErrorBody {
+	ErrorBody::from(bytes::Bytes::from(s.into_bytes()))
+}
+
+pub async fn parse_json_body<T, B, E>(req: Request<B>) -> Result<T, E>
+where
+	T: for<'de> Deserialize<'de>,
+	B: Body,
+	E: From<<B as Body>::Error> + From<Error>,
+{
+	let body = req.into_body().collect().await?.to_bytes();
+	let resp: T = serde_json::from_slice(&body).ok_or_bad_request("Invalid JSON")?;
+	Ok(resp)
+}
+
+pub fn json_ok_response<E, T: Serialize>(res: &T) -> Result<Response<BoxBody<E>>, E>
+where
+	E: From<Error>,
+{
+	let resp_json = serde_json::to_string_pretty(res)
+		.map_err(GarageError::from)
+		.map_err(Error::from)?;
+	Ok(Response::builder()
+		.status(hyper::StatusCode::OK)
+		.header(http::header::CONTENT_TYPE, "application/json")
+		.body(string_body(resp_json))
+		.unwrap())
+}
+
+pub fn body_stream<B, E>(body: B) -> impl Stream<Item = Result<Bytes, E>>
+where
+	B: Body<Data = Bytes>,
+	<B as Body>::Error: Into<E>,
+	E: From<Error>,
+{
+	let stream = http_body_util::BodyStream::new(body);
+	let stream = TryStreamExt::map_err(stream, Into::into);
+	stream.map(|x| {
+		x.and_then(|f| {
+			f.into_data()
+				.map_err(|_| E::from(Error::bad_request("non-data frame")))
+		})
+	})
+}
+
+pub fn is_default<T: Default + PartialEq>(v: &T) -> bool {
+	*v == T::default()
+}
+
+#[cfg(test)]
+mod tests {
+	use super::*;
+
+	#[test]
+	fn parse_bucket_containing_a_key() -> Result<(), Error> {
+		let (bucket, key) = parse_bucket_key("/my_bucket/a/super/file.jpg", None)?;
+		assert_eq!(bucket, "my_bucket");
+		assert_eq!(key.expect("key must be set"), "a/super/file.jpg");
+		Ok(())
+	}
+
+	#[test]
+	fn parse_bucket_containing_no_key() -> Result<(), Error> {
+		let (bucket, key) = parse_bucket_key("/my_bucket/", None)?;
+		assert_eq!(bucket, "my_bucket");
+		assert!(key.is_none());
+		let (bucket, key) = parse_bucket_key("/my_bucket", None)?;
+		assert_eq!(bucket, "my_bucket");
+		assert!(key.is_none());
+		Ok(())
+	}
+
+	#[test]
+	fn parse_bucket_containing_no_bucket() {
+		let parsed = parse_bucket_key("", None);
+		assert!(parsed.is_err());
+		let parsed = parse_bucket_key("/", None);
+		assert!(parsed.is_err());
+		let parsed = parse_bucket_key("////", None);
+		assert!(parsed.is_err());
+	}
+
+	#[test]
+	fn parse_bucket_with_vhost_and_key() -> Result<(), Error> {
+		let (bucket, key) = parse_bucket_key("/a/super/file.jpg", Some("my-bucket"))?;
+		assert_eq!(bucket, "my-bucket");
+		assert_eq!(key.expect("key must be set"), "a/super/file.jpg");
+		Ok(())
+	}
+
+	#[test]
+	fn parse_bucket_with_vhost_no_key() -> Result<(), Error> {
+		let (bucket, key) = parse_bucket_key("", Some("my-bucket"))?;
+		assert_eq!(bucket, "my-bucket");
+		assert!(key.is_none());
+		let (bucket, key) = parse_bucket_key("/", Some("my-bucket"))?;
+		assert_eq!(bucket, "my-bucket");
+		assert!(key.is_none());
+		Ok(())
+	}
+
+	#[test]
+	fn authority_to_host_with_port() -> Result<(), Error> {
+		let domain = authority_to_host("[::1]:3902")?;
+		assert_eq!(domain, "[::1]");
+		let domain2 = authority_to_host("garage.tld:65200")?;
+		assert_eq!(domain2, "garage.tld");
+		let domain3 = authority_to_host("127.0.0.1:80")?;
+		assert_eq!(domain3, "127.0.0.1");
+		Ok(())
+	}
+
+	#[test]
+	fn authority_to_host_without_port() -> Result<(), Error> {
+		let domain = authority_to_host("[::1]")?;
+		assert_eq!(domain, "[::1]");
+		let domain2 = authority_to_host("garage.tld")?;
+		assert_eq!(domain2, "garage.tld");
+		let domain3 = authority_to_host("127.0.0.1")?;
+		assert_eq!(domain3, "127.0.0.1");
+		assert!(authority_to_host("[").is_err());
+		assert!(authority_to_host("[hello").is_err());
+		Ok(())
+	}
+
+	#[test]
+	fn host_to_bucket_test() {
+		assert_eq!(
+			host_to_bucket("john.doe.garage.tld", ".garage.tld").unwrap(),
+			"john.doe"
+		);
+
+		assert_eq!(
+			host_to_bucket("john.doe.garage.tld", "garage.tld").unwrap(),
+			"john.doe"
+		);
+
+		assert_eq!(host_to_bucket("john.doe.com", "garage.tld"), None);
+
+		assert_eq!(host_to_bucket("john.doe.com", ".garage.tld"), None);
+
+		assert_eq!(host_to_bucket("garage.tld", "garage.tld"), None);
+
+		assert_eq!(host_to_bucket("garage.tld", ".garage.tld"), None);
+
+		assert_eq!(host_to_bucket("not-garage.tld", "garage.tld"), None);
+		assert_eq!(host_to_bucket("not-garage.tld", ".garage.tld"), None);
+	}
+
+	#[test]
+	fn test_key_after_prefix() {
+		use std::iter::FromIterator;
+
+		assert_eq!(UTF8_BEFORE_LAST_CHAR as u32, (char::MAX as u32) - 1);
+		assert_eq!(key_after_prefix("a/b/").unwrap().as_str(), "a/b0");
+		assert_eq!(key_after_prefix("€").unwrap().as_str(), "₭");
+		assert_eq!(
+			key_after_prefix("􏿽").unwrap().as_str(),
+			String::from(char::from_u32(0x10FFFE).unwrap())
+		);
+
+		// When the last character is the biggest UTF8 char
+		let a = String::from_iter(['a', char::MAX].iter());
+		assert_eq!(key_after_prefix(a.as_str()).unwrap().as_str(), "b");
+
+		// When all characters are the biggest UTF8 char
+		let b = String::from_iter([char::MAX; 3].iter());
+		assert!(key_after_prefix(b.as_str()).is_none());
+
+		// Check utf8 surrogates
+		let c = String::from('\u{D7FF}');
+		assert_eq!(
+			key_after_prefix(c.as_str()).unwrap().as_str(),
+			String::from('\u{E000}')
+		);
+
+		// Check the character before the biggest one
+		let d = String::from('\u{10FFFE}');
+		assert_eq!(
+			key_after_prefix(d.as_str()).unwrap().as_str(),
+			String::from(char::MAX)
+		);
+	}
+}
+
+#[derive(Serialize)]
+pub struct CustomApiErrorBody {
+	pub code: String,
+	pub message: String,
+	pub region: String,
+	pub path: String,
+}

src/api/common/lib.rs

@@ -0,0 +1,12 @@
+//! Crate for serving a S3 compatible API
+#[macro_use]
+extern crate tracing;
+
+pub mod common_error;
+
+pub mod encoding;
+pub mod generic_server;
+pub mod helpers;
+pub mod router_macros;
+/// This mode is public only to help testing. Don't expect stability here
+pub mod signature;

src/api/common/router_macros.rs

@@ -0,0 +1,226 @@
+/// This macro is used to generate very repetitive match {} blocks in this module
+/// It is _not_ made to be used anywhere else
+#[macro_export]
+macro_rules! router_match {
+    (@match $enum:expr , [ $($endpoint:ident,)* ]) => {{
+        // usage: router_match {@match my_enum, [ VariantWithField1, VariantWithField2 ..] }
+        // returns true if the variant was one of the listed variants, false otherwise.
+        match $enum {
+            $(
+            Endpoint::$endpoint { .. } => true,
+            )*
+            _ => false
+        }
+    }};
+    (@extract $enum:expr , $param:ident, [ $($endpoint:ident,)* ]) => {{
+        // usage: router_match {@extract my_enum, field_name, [ VariantWithField1, VariantWithField2 ..] }
+        // returns Some(field_value), or None if the variant was not one of the listed variants.
+        match $enum {
+            $(
+            Endpoint::$endpoint {$param, ..} => Some($param),
+            )*
+            _ => None
+        }
+    }};
+    (@gen_path_parser ($method:expr, $reqpath:expr, $query:expr)
+     [
+     $($meth:ident $path:pat $(if $required:ident)? => $api:ident $(($($conv:ident :: $param:ident),*))?,)*
+     ]) => {{
+        {
+            #[allow(unused_parens)]
+            match ($method, $reqpath) {
+                $(
+                    (&Method::$meth, $path) if true $(&& $query.$required.is_some())? => Endpoint::$api {
+                        $($(
+                            $param: router_match!(@@parse_param $query, $conv, $param),
+                        )*)?
+                    },
+                )*
+                (m, p) => {
+                    return Err(Error::bad_request(format!(
+                        "Unknown API endpoint: {} {}",
+                        m, p
+                    )))
+                }
+            }
+        }
+    }};
+    (@gen_parser ($keyword:expr, $key:ident, $query:expr, $header:expr),
+        key: [$($kw_k:ident $(if $required_k:ident)? $(header $header_k:expr)? => $api_k:ident $(($($conv_k:ident :: $param_k:ident),*))?,)*],
+        no_key: [$($kw_nk:ident $(if $required_nk:ident)? $(if_header $header_nk:expr)? => $api_nk:ident $(($($conv_nk:ident :: $param_nk:ident),*))?,)*]) => {{
+        // usage: router_match {@gen_parser (keyword, key, query, header),
+        //   key: [
+        //      SOME_KEYWORD => VariantWithKey,
+        //      ...
+        //   ],
+        //   no_key: [
+        //      SOME_KEYWORD => VariantWithoutKey,
+        //      ...
+        //   ]
+        // }
+        // See in from_{method} for more detailed usage.
+        match ($keyword, !$key.is_empty()){
+            $(
+            (Keyword::$kw_k, true) if true $(&& $query.$required_k.is_some())? $(&& $header.contains_key($header_k))? => Ok(Endpoint::$api_k {
+                $key,
+                $($(
+                    $param_k: router_match!(@@parse_param $query, $conv_k, $param_k),
+                )*)?
+            }),
+            )*
+            $(
+            (Keyword::$kw_nk, false) $(if $query.$required_nk.is_some())? $(if $header.contains($header_nk))? => Ok(Endpoint::$api_nk {
+                $($(
+                    $param_nk: router_match!(@@parse_param $query, $conv_nk, $param_nk),
+                )*)?
+            }),
+            )*
+            (kw, _) => Err(Error::bad_request(format!("Invalid endpoint: {}", kw)))
+        }
+    }};
+
+    (@@parse_param $query:expr, query_opt, $param:ident) => {{
+        // extract optional query parameter
+        $query.$param.take().map(|param| param.into_owned())
+    }};
+    (@@parse_param $query:expr, query, $param:ident) => {{
+        // extract mendatory query parameter
+        $query.$param.take().ok_or_bad_request("Missing argument for endpoint")?.into_owned()
+    }};
+    (@@parse_param $query:expr, opt_parse, $param:ident) => {{
+        // extract and parse optional query parameter
+        // missing parameter is file, however parse error is reported as an error
+        $query.$param
+            .take()
+            .map(|param| param.parse())
+            .transpose()
+            .map_err(|_| Error::bad_request("Failed to parse query parameter"))?
+    }};
+    (@@parse_param $query:expr, parse, $param:ident) => {{
+        // extract and parse mandatory query parameter
+        // both missing and un-parseable parameters are reported as errors
+        $query.$param.take().ok_or_bad_request("Missing argument for endpoint")?
+            .parse()
+            .map_err(|_| Error::bad_request("Failed to parse query parameter"))?
+    }};
+    (@func
+    $(#[$doc:meta])*
+     pub enum Endpoint {
+        $(
+            $(#[$outer:meta])*
+            $variant:ident $({
+                $($name:ident: $ty:ty,)*
+            })?,
+        )*
+    }) => {
+    $(#[$doc])*
+        pub enum Endpoint {
+            $(
+                $(#[$outer])*
+                $variant $({
+                    $($name: $ty, )*
+                })?,
+            )*
+        }
+        impl Endpoint {
+            pub fn name(&self) -> &'static str {
+                match self {
+                    $(Endpoint::$variant $({ $($name: _,)* .. })? => stringify!($variant),)*
+                }
+            }
+        }
+    };
+}
+
+/// This macro is used to generate part of the code in this module. It must be called only one, and
+/// is useless outside of this module.
+#[macro_export]
+macro_rules! generateQueryParameters {
+    (
+        keywords: [ $($kw_param:expr => $kw_name: ident),* ],
+        fields: [ $($f_param:expr => $f_name:ident),* ]
+    ) => {
+        #[derive(Debug)]
+        #[allow(non_camel_case_types)]
+        #[allow(clippy::upper_case_acronyms)]
+        enum Keyword {
+            EMPTY,
+            $( $kw_name, )*
+        }
+
+        impl std::fmt::Display for Keyword {
+            fn fmt(&self, f: &mut std::fmt::Formatter) -> std::fmt::Result {
+                match self {
+                    Keyword::EMPTY => write!(f, "``"),
+                    $( Keyword::$kw_name => write!(f, "`{}`", $kw_param), )*
+                }
+            }
+        }
+
+        impl Default for Keyword {
+            fn default() -> Self {
+                Keyword::EMPTY
+            }
+        }
+
+        /// Struct containing all query parameters used in endpoints. Think of it as an HashMap,
+        /// but with keys statically known.
+        #[derive(Debug, Default)]
+        struct QueryParameters<'a> {
+            keyword: Option<Keyword>,
+            $(
+            $f_name: Option<Cow<'a, str>>,
+            )*
+        }
+
+        impl<'a> QueryParameters<'a> {
+            /// Build this struct from the query part of an URI.
+            fn from_query(query: &'a str) -> Result<Self, Error> {
+                let mut res: Self = Default::default();
+                for (k, v) in url::form_urlencoded::parse(query.as_bytes()) {
+                    match k.as_ref() {
+                        $(
+                            $kw_param => if let Some(prev_kw) = res.keyword.replace(Keyword::$kw_name) {
+                                return Err(Error::bad_request(format!(
+                                    "Multiple keywords: '{}' and '{}'", prev_kw, $kw_param
+                                )));
+                            },
+                        )*
+                        $(
+                            $f_param => if !v.is_empty() {
+                                if res.$f_name.replace(v).is_some() {
+                                    return Err(Error::bad_request(format!(
+                                        "Query parameter repeated: '{}'", k
+                                    )));
+                                }
+                            },
+                        )*
+                        _ => {
+                            if !(k.starts_with("response-") || k.starts_with("X-Amz-")) {
+                                debug!("Received an unknown query parameter: '{}'", k);
+                            }
+                        }
+                    };
+                }
+                Ok(res)
+            }
+
+            /// Get an error message in case not all parameters where used when extracting them to
+            /// build an Endpoint variant
+            fn nonempty_message(&self) -> Option<&str> {
+                if self.keyword.is_some() {
+                    Some("Keyword not used")
+                } $(
+                    else if self.$f_name.is_some() {
+                        Some(concat!("'", $f_param, "'"))
+                    }
+                )* else {
+                    None
+                }
+            }
+        }
+    }
+}
+
+pub use generateQueryParameters;
+pub use router_match;

src/api/common/signature/error.rs

@@ -0,0 +1,32 @@
+use err_derive::Error;
+
+use crate::common_error::CommonError;
+pub use crate::common_error::{CommonErrorDerivative, OkOrBadRequest, OkOrInternalError};
+
+/// Errors of this crate
+#[derive(Debug, Error)]
+pub enum Error {
+	#[error(display = "{}", _0)]
+	/// Error from common error
+	Common(CommonError),
+
+	/// Authorization Header Malformed
+	#[error(display = "Authorization header malformed, unexpected scope: {}", _0)]
+	AuthorizationHeaderMalformed(String),
+
+	// Category: bad request
+	/// The request contained an invalid UTF-8 sequence in its path or in other parameters
+	#[error(display = "Invalid UTF-8: {}", _0)]
+	InvalidUtf8Str(#[error(source)] std::str::Utf8Error),
+}
+
+impl<T> From<T> for Error
+where
+	CommonError: From<T>,
+{
+	fn from(err: T) -> Self {
+		Error::Common(CommonError::from(err))
+	}
+}
+
+impl CommonErrorDerivative for Error {}

src/api/common/signature/mod.rs

@@ -0,0 +1,78 @@
+use chrono::{DateTime, Utc};
+use hmac::{Hmac, Mac};
+use sha2::Sha256;
+
+use hyper::{body::Incoming as IncomingBody, Request};
+
+use garage_model::garage::Garage;
+use garage_model::key_table::Key;
+use garage_util::data::{sha256sum, Hash};
+
+use error::*;
+
+pub mod error;
+pub mod payload;
+pub mod streaming;
+
+pub const SHORT_DATE: &str = "%Y%m%d";
+pub const LONG_DATETIME: &str = "%Y%m%dT%H%M%SZ";
+
+type HmacSha256 = Hmac<Sha256>;
+
+pub async fn verify_request(
+	garage: &Garage,
+	mut req: Request<IncomingBody>,
+	service: &'static str,
+) -> Result<(Request<streaming::ReqBody>, Key, Option<Hash>), Error> {
+	let (api_key, mut content_sha256) =
+		payload::check_payload_signature(&garage, &mut req, service).await?;
+	let api_key =
+		api_key.ok_or_else(|| Error::forbidden("Garage does not support anonymous access yet"))?;
+
+	let req = streaming::parse_streaming_body(
+		&api_key,
+		req,
+		&mut content_sha256,
+		&garage.config.s3_api.s3_region,
+		service,
+	)?;
+
+	Ok((req, api_key, content_sha256))
+}
+
+pub fn verify_signed_content(expected_sha256: Hash, body: &[u8]) -> Result<(), Error> {
+	if expected_sha256 != sha256sum(body) {
+		return Err(Error::bad_request(
+			"Request content hash does not match signed hash".to_string(),
+		));
+	}
+	Ok(())
+}
+
+pub fn signing_hmac(
+	datetime: &DateTime<Utc>,
+	secret_key: &str,
+	region: &str,
+	service: &str,
+) -> Result<HmacSha256, crypto_common::InvalidLength> {
+	let secret = String::from("AWS4") + secret_key;
+	let mut date_hmac = HmacSha256::new_from_slice(secret.as_bytes())?;
+	date_hmac.update(datetime.format(SHORT_DATE).to_string().as_bytes());
+	let mut region_hmac = HmacSha256::new_from_slice(&date_hmac.finalize().into_bytes())?;
+	region_hmac.update(region.as_bytes());
+	let mut service_hmac = HmacSha256::new_from_slice(&region_hmac.finalize().into_bytes())?;
+	service_hmac.update(service.as_bytes());
+	let mut signing_hmac = HmacSha256::new_from_slice(&service_hmac.finalize().into_bytes())?;
+	signing_hmac.update(b"aws4_request");
+	let hmac = HmacSha256::new_from_slice(&signing_hmac.finalize().into_bytes())?;
+	Ok(hmac)
+}
+
+pub fn compute_scope(datetime: &DateTime<Utc>, region: &str, service: &str) -> String {
+	format!(
+		"{}/{}/{}/aws4_request",
+		datetime.format(SHORT_DATE),
+		region,
+		service
+	)
+}

src/api/common/signature/payload.rs

@@ -0,0 +1,562 @@
+use std::collections::HashMap;
+use std::convert::TryFrom;
+
+use chrono::{DateTime, Duration, NaiveDateTime, TimeZone, Utc};
+use hmac::Mac;
+use hyper::header::{HeaderMap, HeaderName, HeaderValue, AUTHORIZATION, HOST};
+use hyper::{body::Incoming as IncomingBody, Method, Request};
+use sha2::{Digest, Sha256};
+
+use garage_table::*;
+use garage_util::data::Hash;
+
+use garage_model::garage::Garage;
+use garage_model::key_table::*;
+
+use super::LONG_DATETIME;
+use super::{compute_scope, signing_hmac};
+
+use crate::encoding::uri_encode;
+use crate::signature::error::*;
+
+pub const X_AMZ_ALGORITHM: HeaderName = HeaderName::from_static("x-amz-algorithm");
+pub const X_AMZ_CREDENTIAL: HeaderName = HeaderName::from_static("x-amz-credential");
+pub const X_AMZ_DATE: HeaderName = HeaderName::from_static("x-amz-date");
+pub const X_AMZ_EXPIRES: HeaderName = HeaderName::from_static("x-amz-expires");
+pub const X_AMZ_SIGNEDHEADERS: HeaderName = HeaderName::from_static("x-amz-signedheaders");
+pub const X_AMZ_SIGNATURE: HeaderName = HeaderName::from_static("x-amz-signature");
+pub const X_AMZ_CONTENT_SH256: HeaderName = HeaderName::from_static("x-amz-content-sha256");
+
+pub const AWS4_HMAC_SHA256: &str = "AWS4-HMAC-SHA256";
+pub const UNSIGNED_PAYLOAD: &str = "UNSIGNED-PAYLOAD";
+pub const STREAMING_AWS4_HMAC_SHA256_PAYLOAD: &str = "STREAMING-AWS4-HMAC-SHA256-PAYLOAD";
+
+pub type QueryMap = HeaderMap<QueryValue>;
+pub struct QueryValue {
+	/// Original key with potential uppercase characters,
+	/// for use in signature calculation
+	key: String,
+	value: String,
+}
+
+pub async fn check_payload_signature(
+	garage: &Garage,
+	request: &mut Request<IncomingBody>,
+	service: &'static str,
+) -> Result<(Option<Key>, Option<Hash>), Error> {
+	let query = parse_query_map(request.uri())?;
+
+	if query.contains_key(&X_AMZ_ALGORITHM) {
+		// We check for presigned-URL-style authentication first, because
+		// the browser or something else could inject an Authorization header
+		// that is totally unrelated to AWS signatures.
+		check_presigned_signature(garage, service, request, query).await
+	} else if request.headers().contains_key(AUTHORIZATION) {
+		check_standard_signature(garage, service, request, query).await
+	} else {
+		// Unsigned (anonymous) request
+		let content_sha256 = request
+			.headers()
+			.get("x-amz-content-sha256")
+			.filter(|c| c.as_bytes() != UNSIGNED_PAYLOAD.as_bytes());
+		if let Some(content_sha256) = content_sha256 {
+			let sha256 = hex::decode(content_sha256)
+				.ok()
+				.and_then(|bytes| Hash::try_from(&bytes))
+				.ok_or_bad_request("Invalid content sha256 hash")?;
+			Ok((None, Some(sha256)))
+		} else {
+			Ok((None, None))
+		}
+	}
+}
+
+async fn check_standard_signature(
+	garage: &Garage,
+	service: &'static str,
+	request: &Request<IncomingBody>,
+	query: QueryMap,
+) -> Result<(Option<Key>, Option<Hash>), Error> {
+	let authorization = Authorization::parse_header(request.headers())?;
+
+	// Verify that all necessary request headers are included in signed_headers
+	// The following must be included for all signatures:
+	// - the Host header (mandatory)
+	// - all x-amz-* headers used in the request
+	// AWS also indicates that the Content-Type header should be signed if
+	// it is used, but Minio client doesn't sign it so we don't check it for compatibility.
+	let signed_headers = split_signed_headers(&authorization)?;
+	verify_signed_headers(request.headers(), &signed_headers)?;
+
+	let canonical_request = canonical_request(
+		service,
+		request.method(),
+		request.uri().path(),
+		&query,
+		request.headers(),
+		&signed_headers,
+		&authorization.content_sha256,
+	)?;
+	let string_to_sign = string_to_sign(
+		&authorization.date,
+		&authorization.scope,
+		&canonical_request,
+	);
+
+	trace!("canonical request:\n{}", canonical_request);
+	trace!("string to sign:\n{}", string_to_sign);
+
+	let key = verify_v4(garage, service, &authorization, string_to_sign.as_bytes()).await?;
+
+	let content_sha256 = if authorization.content_sha256 == UNSIGNED_PAYLOAD {
+		None
+	} else if authorization.content_sha256 == STREAMING_AWS4_HMAC_SHA256_PAYLOAD {
+		let bytes = hex::decode(authorization.signature).ok_or_bad_request("Invalid signature")?;
+		Some(Hash::try_from(&bytes).ok_or_bad_request("Invalid signature")?)
+	} else {
+		let bytes = hex::decode(authorization.content_sha256)
+			.ok_or_bad_request("Invalid content sha256 hash")?;
+		Some(Hash::try_from(&bytes).ok_or_bad_request("Invalid content sha256 hash")?)
+	};
+
+	Ok((Some(key), content_sha256))
+}
+
+async fn check_presigned_signature(
+	garage: &Garage,
+	service: &'static str,
+	request: &mut Request<IncomingBody>,
+	mut query: QueryMap,
+) -> Result<(Option<Key>, Option<Hash>), Error> {
+	let algorithm = query.get(&X_AMZ_ALGORITHM).unwrap();
+	let authorization = Authorization::parse_presigned(&algorithm.value, &query)?;
+
+	// Verify that all necessary request headers are included in signed_headers
+	// For AWSv4 pre-signed URLs, the following must be included:
+	// - the Host header (mandatory)
+	// - all x-amz-* headers used in the request
+	let signed_headers = split_signed_headers(&authorization)?;
+	verify_signed_headers(request.headers(), &signed_headers)?;
+
+	// The X-Amz-Signature value is passed as a query parameter,
+	// but the signature cannot be computed from a string that contains itself.
+	// AWS specifies that all query params except X-Amz-Signature are included
+	// in the canonical request.
+	query.remove(&X_AMZ_SIGNATURE);
+	let canonical_request = canonical_request(
+		service,
+		request.method(),
+		request.uri().path(),
+		&query,
+		request.headers(),
+		&signed_headers,
+		&authorization.content_sha256,
+	)?;
+	let string_to_sign = string_to_sign(
+		&authorization.date,
+		&authorization.scope,
+		&canonical_request,
+	);
+
+	trace!("canonical request (presigned url):\n{}", canonical_request);
+	trace!("string to sign (presigned url):\n{}", string_to_sign);
+
+	let key = verify_v4(garage, service, &authorization, string_to_sign.as_bytes()).await?;
+
+	// In the page on presigned URLs, AWS specifies that if a signed query
+	// parameter and a signed header of the same name have different values,
+	// then an InvalidRequest error is raised.
+	let headers_mut = request.headers_mut();
+	for (name, value) in query.iter() {
+		if let Some(existing) = headers_mut.get(name) {
+			if signed_headers.contains(&name) && existing.as_bytes() != value.value.as_bytes() {
+				return Err(Error::bad_request(format!(
+					"Conflicting values for `{}` in query parameters and request headers",
+					name
+				)));
+			}
+		}
+		if name.as_str().starts_with("x-amz-") {
+			// Query parameters that start by x-amz- are actually intended to stand in for
+			// headers that can't be added at the time the request is made.
+			// What we do is just add them to the Request object as regular headers,
+			// that will be handled downstream as if they were included like in a normal request.
+			// (Here we allow such query parameters to override headers with the same name
+			// that are not signed, however there is not much reason that this would happen)
+			headers_mut.insert(
+				name,
+				HeaderValue::from_bytes(value.value.as_bytes())
+					.ok_or_bad_request("invalid query parameter value")?,
+			);
+		}
+	}
+
+	// Presigned URLs always use UNSIGNED-PAYLOAD,
+	// so there is no sha256 hash to return.
+	Ok((Some(key), None))
+}
+
+pub fn parse_query_map(uri: &http::uri::Uri) -> Result<QueryMap, Error> {
+	let mut query = QueryMap::with_capacity(0);
+	if let Some(query_str) = uri.query() {
+		let query_pairs = url::form_urlencoded::parse(query_str.as_bytes());
+		for (key, val) in query_pairs {
+			let name =
+				HeaderName::from_bytes(key.as_bytes()).ok_or_bad_request("Invalid header name")?;
+
+			let value = QueryValue {
+				key: key.to_string(),
+				value: val.into_owned(),
+			};
+
+			if query.insert(name, value).is_some() {
+				return Err(Error::bad_request(format!(
+					"duplicate query parameter: `{}`",
+					key
+				)));
+			}
+		}
+	}
+	Ok(query)
+}
+
+fn parse_credential(cred: &str) -> Result<(String, String), Error> {
+	let first_slash = cred
+		.find('/')
+		.ok_or_bad_request("Credentials does not contain '/' in authorization field")?;
+	let (key_id, scope) = cred.split_at(first_slash);
+	Ok((
+		key_id.to_string(),
+		scope.trim_start_matches('/').to_string(),
+	))
+}
+
+fn split_signed_headers(authorization: &Authorization) -> Result<Vec<HeaderName>, Error> {
+	let mut signed_headers = authorization
+		.signed_headers
+		.split(';')
+		.map(HeaderName::try_from)
+		.collect::<Result<Vec<HeaderName>, _>>()
+		.ok_or_bad_request("invalid header name")?;
+	signed_headers.sort_by(|h1, h2| h1.as_str().cmp(h2.as_str()));
+	Ok(signed_headers)
+}
+
+fn verify_signed_headers(headers: &HeaderMap, signed_headers: &[HeaderName]) -> Result<(), Error> {
+	if !signed_headers.contains(&HOST) {
+		return Err(Error::bad_request("Header `Host` should be signed"));
+	}
+	for (name, _) in headers.iter() {
+		if name.as_str().starts_with("x-amz-") {
+			if !signed_headers.contains(name) {
+				return Err(Error::bad_request(format!(
+					"Header `{}` should be signed",
+					name
+				)));
+			}
+		}
+	}
+	Ok(())
+}
+
+pub fn string_to_sign(datetime: &DateTime<Utc>, scope_string: &str, canonical_req: &str) -> String {
+	let mut hasher = Sha256::default();
+	hasher.update(canonical_req.as_bytes());
+	[
+		AWS4_HMAC_SHA256,
+		&datetime.format(LONG_DATETIME).to_string(),
+		scope_string,
+		&hex::encode(hasher.finalize().as_slice()),
+	]
+	.join("\n")
+}
+
+pub fn canonical_request(
+	service: &'static str,
+	method: &Method,
+	canonical_uri: &str,
+	query: &QueryMap,
+	headers: &HeaderMap,
+	signed_headers: &[HeaderName],
+	content_sha256: &str,
+) -> Result<String, Error> {
+	// There seems to be evidence that in AWSv4 signatures, the path component is url-encoded
+	// a second time when building the canonical request, as specified in this documentation page:
+	// -> https://docs.aws.amazon.com/rolesanywhere/latest/userguide/authentication-sign-process.html
+	// However this documentation page is for a specific service ("roles anywhere"), and
+	// in the S3 service we know for a fact that there is no double-urlencoding, because all of
+	// the tests we made with external software work without it.
+	//
+	// The theory is that double-urlencoding occurs for all services except S3,
+	// which is what is implemented in rusoto_signature:
+	// -> https://docs.rs/rusoto_signature/latest/src/rusoto_signature/signature.rs.html#464
+	//
+	// Digging into the code of the official AWS Rust SDK, we learn that double-URI-encoding can
+	// be set or unset on a per-request basis (the signature crates, aws-sigv4 and aws-sig-auth,
+	// are agnostic to this). Grepping the codebase confirms that S3 is the only API for which
+	// double_uri_encode is set to false, meaning it is true (its default value) for all other
+	// AWS services. We will therefore implement this behavior in Garage as well.
+	//
+	// Note that this documentation page, which is touted as the "authoritative reference" on
+	// AWSv4 signatures, makes no mention of either single- or double-urlencoding:
+	// -> https://docs.aws.amazon.com/IAM/latest/UserGuide/create-signed-request.html
+	// This page of the S3 documentation does also not mention anything specific:
+	// -> https://docs.aws.amazon.com/AmazonS3/latest/API/sig-v4-header-based-auth.html
+	//
+	// Note that there is also the issue of path normalization, which I hope is unrelated to the
+	// one of URI-encoding. At least in aws-sigv4 both parameters can be set independently,
+	// and rusoto_signature does not seem to do any effective path normalization, even though
+	// it mentions it in the comments (same link to the source code as above).
+	// We make the explicit choice of NOT normalizing paths in the K2V API because doing so
+	// would make non-normalized paths invalid K2V partition keys, and we don't want that.
+	let canonical_uri: std::borrow::Cow<str> = if service != "s3" {
+		uri_encode(canonical_uri, false).into()
+	} else {
+		canonical_uri.into()
+	};
+
+	// Canonical query string from passed HeaderMap
+	let canonical_query_string = {
+		let mut items = Vec::with_capacity(query.len());
+		for (_, QueryValue { key, value }) in query.iter() {
+			items.push(uri_encode(&key, true) + "=" + &uri_encode(&value, true));
+		}
+		items.sort();
+		items.join("&")
+	};
+
+	// Canonical header string calculated from signed headers
+	let canonical_header_string = signed_headers
+		.iter()
+		.map(|name| {
+			let value = headers
+				.get(name)
+				.ok_or_bad_request(format!("signed header `{}` is not present", name))?;
+			let value = std::str::from_utf8(value.as_bytes())?;
+			Ok(format!("{}:{}", name.as_str(), value.trim()))
+		})
+		.collect::<Result<Vec<String>, Error>>()?
+		.join("\n");
+	let signed_headers = signed_headers.join(";");
+
+	let list = [
+		method.as_str(),
+		&canonical_uri,
+		&canonical_query_string,
+		&canonical_header_string,
+		"",
+		&signed_headers,
+		content_sha256,
+	];
+	Ok(list.join("\n"))
+}
+
+pub fn parse_date(date: &str) -> Result<DateTime<Utc>, Error> {
+	let date: NaiveDateTime =
+		NaiveDateTime::parse_from_str(date, LONG_DATETIME).ok_or_bad_request("Invalid date")?;
+	Ok(Utc.from_utc_datetime(&date))
+}
+
+pub async fn verify_v4(
+	garage: &Garage,
+	service: &str,
+	auth: &Authorization,
+	payload: &[u8],
+) -> Result<Key, Error> {
+	let scope_expected = compute_scope(&auth.date, &garage.config.s3_api.s3_region, service);
+	if auth.scope != scope_expected {
+		return Err(Error::AuthorizationHeaderMalformed(auth.scope.to_string()));
+	}
+
+	let key = garage
+		.key_table
+		.get(&EmptyKey, &auth.key_id)
+		.await?
+		.filter(|k| !k.state.is_deleted())
+		.ok_or_else(|| Error::forbidden(format!("No such key: {}", &auth.key_id)))?;
+	let key_p = key.params().unwrap();
+
+	let mut hmac = signing_hmac(
+		&auth.date,
+		&key_p.secret_key,
+		&garage.config.s3_api.s3_region,
+		service,
+	)
+	.ok_or_internal_error("Unable to build signing HMAC")?;
+	hmac.update(payload);
+	let signature =
+		hex::decode(&auth.signature).map_err(|_| Error::forbidden("Invalid signature"))?;
+	if hmac.verify_slice(&signature).is_err() {
+		return Err(Error::forbidden("Invalid signature"));
+	}
+
+	Ok(key)
+}
+
+// ============ Authorization header, or X-Amz-* query params =========
+
+pub struct Authorization {
+	key_id: String,
+	scope: String,
+	signed_headers: String,
+	signature: String,
+	content_sha256: String,
+	date: DateTime<Utc>,
+}
+
+impl Authorization {
+	fn parse_header(headers: &HeaderMap) -> Result<Self, Error> {
+		let authorization = headers
+			.get(AUTHORIZATION)
+			.ok_or_bad_request("Missing authorization header")?
+			.to_str()?;
+
+		let (auth_kind, rest) = authorization
+			.split_once(' ')
+			.ok_or_bad_request("Authorization field to short")?;
+
+		if auth_kind != AWS4_HMAC_SHA256 {
+			return Err(Error::bad_request("Unsupported authorization method"));
+		}
+
+		let mut auth_params = HashMap::new();
+		for auth_part in rest.split(',') {
+			let auth_part = auth_part.trim();
+			let eq = auth_part
+				.find('=')
+				.ok_or_bad_request("Field without value in authorization header")?;
+			let (key, value) = auth_part.split_at(eq);
+			auth_params.insert(key.to_string(), value.trim_start_matches('=').to_string());
+		}
+
+		let cred = auth_params
+			.get("Credential")
+			.ok_or_bad_request("Could not find Credential in Authorization field")?;
+		let signed_headers = auth_params
+			.get("SignedHeaders")
+			.ok_or_bad_request("Could not find SignedHeaders in Authorization field")?
+			.to_string();
+		let signature = auth_params
+			.get("Signature")
+			.ok_or_bad_request("Could not find Signature in Authorization field")?
+			.to_string();
+
+		let content_sha256 = headers
+			.get(X_AMZ_CONTENT_SH256)
+			.ok_or_bad_request("Missing X-Amz-Content-Sha256 field")?;
+
+		let date = headers
+			.get(X_AMZ_DATE)
+			.ok_or_bad_request("Missing X-Amz-Date field")
+			.map_err(Error::from)?
+			.to_str()?;
+		let date = parse_date(date)?;
+
+		if Utc::now() - date > Duration::hours(24) {
+			return Err(Error::bad_request("Date is too old".to_string()));
+		}
+
+		let (key_id, scope) = parse_credential(cred)?;
+		let auth = Authorization {
+			key_id,
+			scope,
+			signed_headers,
+			signature,
+			content_sha256: content_sha256.to_str()?.to_string(),
+			date,
+		};
+		Ok(auth)
+	}
+
+	fn parse_presigned(algorithm: &str, query: &QueryMap) -> Result<Self, Error> {
+		if algorithm != AWS4_HMAC_SHA256 {
+			return Err(Error::bad_request(
+				"Unsupported authorization method".to_string(),
+			));
+		}
+
+		let cred = query
+			.get(&X_AMZ_CREDENTIAL)
+			.ok_or_bad_request("X-Amz-Credential not found in query parameters")?;
+		let signed_headers = query
+			.get(&X_AMZ_SIGNEDHEADERS)
+			.ok_or_bad_request("X-Amz-SignedHeaders not found in query parameters")?;
+		let signature = query
+			.get(&X_AMZ_SIGNATURE)
+			.ok_or_bad_request("X-Amz-Signature not found in query parameters")?;
+
+		let duration = query
+			.get(&X_AMZ_EXPIRES)
+			.ok_or_bad_request("X-Amz-Expires not found in query parameters")?
+			.value
+			.parse()
+			.map_err(|_| Error::bad_request("X-Amz-Expires is not a number".to_string()))?;
+
+		if duration > 7 * 24 * 3600 {
+			return Err(Error::bad_request(
+				"X-Amz-Expires may not exceed a week".to_string(),
+			));
+		}
+
+		let date = query
+			.get(&X_AMZ_DATE)
+			.ok_or_bad_request("Missing X-Amz-Date field")?;
+		let date = parse_date(&date.value)?;
+
+		if Utc::now() - date > Duration::seconds(duration) {
+			return Err(Error::bad_request("Date is too old".to_string()));
+		}
+
+		let (key_id, scope) = parse_credential(&cred.value)?;
+		Ok(Authorization {
+			key_id,
+			scope,
+			signed_headers: signed_headers.value.clone(),
+			signature: signature.value.clone(),
+			content_sha256: UNSIGNED_PAYLOAD.to_string(),
+			date,
+		})
+	}
+
+	pub fn parse_form(params: &HeaderMap) -> Result<Self, Error> {
+		let algorithm = params
+			.get(X_AMZ_ALGORITHM)
+			.ok_or_bad_request("Missing X-Amz-Algorithm header")?
+			.to_str()?;
+		if algorithm != AWS4_HMAC_SHA256 {
+			return Err(Error::bad_request(
+				"Unsupported authorization method".to_string(),
+			));
+		}
+
+		let credential = params
+			.get(X_AMZ_CREDENTIAL)
+			.ok_or_else(|| Error::forbidden("Garage does not support anonymous access yet"))?
+			.to_str()?;
+		let signature = params
+			.get(X_AMZ_SIGNATURE)
+			.ok_or_bad_request("No signature was provided")?
+			.to_str()?
+			.to_string();
+		let date = params
+			.get(X_AMZ_DATE)
+			.ok_or_bad_request("No date was provided")?
+			.to_str()?;
+		let date = parse_date(date)?;
+
+		if Utc::now() - date > Duration::hours(24) {
+			return Err(Error::bad_request("Date is too old".to_string()));
+		}
+
+		let (key_id, scope) = parse_credential(credential)?;
+		let auth = Authorization {
+			key_id,
+			scope,
+			signed_headers: "".to_string(),
+			signature,
+			content_sha256: UNSIGNED_PAYLOAD.to_string(),
+			date,
+		};
+		Ok(auth)
+	}
+}

src/api/common/signature/streaming.rs

@@ -0,0 +1,373 @@
+use std::pin::Pin;
+
+use chrono::{DateTime, NaiveDateTime, TimeZone, Utc};
+use futures::prelude::*;
+use futures::task;
+use garage_model::key_table::Key;
+use hmac::Mac;
+use http_body_util::StreamBody;
+use hyper::body::{Bytes, Incoming as IncomingBody};
+use hyper::Request;
+
+use garage_util::data::Hash;
+
+use super::{compute_scope, sha256sum, HmacSha256, LONG_DATETIME};
+
+use crate::helpers::*;
+use crate::signature::error::*;
+use crate::signature::payload::{
+	STREAMING_AWS4_HMAC_SHA256_PAYLOAD, X_AMZ_CONTENT_SH256, X_AMZ_DATE,
+};
+
+pub const AWS4_HMAC_SHA256_PAYLOAD: &str = "AWS4-HMAC-SHA256-PAYLOAD";
+
+pub type ReqBody = BoxBody<Error>;
+
+pub fn parse_streaming_body(
+	api_key: &Key,
+	req: Request<IncomingBody>,
+	content_sha256: &mut Option<Hash>,
+	region: &str,
+	service: &str,
+) -> Result<Request<ReqBody>, Error> {
+	match req.headers().get(X_AMZ_CONTENT_SH256) {
+		Some(header) if header == STREAMING_AWS4_HMAC_SHA256_PAYLOAD => {
+			let signature = content_sha256
+				.take()
+				.ok_or_bad_request("No signature provided")?;
+
+			let secret_key = &api_key
+				.state
+				.as_option()
+				.ok_or_internal_error("Deleted key state")?
+				.secret_key;
+
+			let date = req
+				.headers()
+				.get(X_AMZ_DATE)
+				.ok_or_bad_request("Missing X-Amz-Date field")?
+				.to_str()?;
+			let date: NaiveDateTime = NaiveDateTime::parse_from_str(date, LONG_DATETIME)
+				.ok_or_bad_request("Invalid date")?;
+			let date: DateTime<Utc> = Utc.from_utc_datetime(&date);
+
+			let scope = compute_scope(&date, region, service);
+			let signing_hmac = crate::signature::signing_hmac(&date, secret_key, region, service)
+				.ok_or_internal_error("Unable to build signing HMAC")?;
+
+			Ok(req.map(move |body| {
+				let stream = body_stream::<_, Error>(body);
+				let signed_payload_stream =
+					SignedPayloadStream::new(stream, signing_hmac, date, &scope, signature)
+						.map(|x| x.map(hyper::body::Frame::data))
+						.map_err(Error::from);
+				ReqBody::new(StreamBody::new(signed_payload_stream))
+			}))
+		}
+		_ => Ok(req.map(|body| ReqBody::new(http_body_util::BodyExt::map_err(body, Error::from)))),
+	}
+}
+
+/// Result of `sha256("")`
+const EMPTY_STRING_HEX_DIGEST: &str =
+	"e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855";
+
+fn compute_streaming_payload_signature(
+	signing_hmac: &HmacSha256,
+	date: DateTime<Utc>,
+	scope: &str,
+	previous_signature: Hash,
+	content_sha256: Hash,
+) -> Result<Hash, Error> {
+	let string_to_sign = [
+		AWS4_HMAC_SHA256_PAYLOAD,
+		&date.format(LONG_DATETIME).to_string(),
+		scope,
+		&hex::encode(previous_signature),
+		EMPTY_STRING_HEX_DIGEST,
+		&hex::encode(content_sha256),
+	]
+	.join("\n");
+
+	let mut hmac = signing_hmac.clone();
+	hmac.update(string_to_sign.as_bytes());
+
+	Ok(Hash::try_from(&hmac.finalize().into_bytes()).ok_or_internal_error("Invalid signature")?)
+}
+
+mod payload {
+	use garage_util::data::Hash;
+
+	pub enum Error<I> {
+		Parser(nom::error::Error<I>),
+		BadSignature,
+	}
+
+	impl<I> Error<I> {
+		pub fn description(&self) -> &str {
+			match *self {
+				Error::Parser(ref e) => e.code.description(),
+				Error::BadSignature => "Bad signature",
+			}
+		}
+	}
+
+	#[derive(Debug, Clone)]
+	pub struct Header {
+		pub size: usize,
+		pub signature: Hash,
+	}
+
+	impl Header {
+		pub fn parse(input: &[u8]) -> nom::IResult<&[u8], Self, Error<&[u8]>> {
+			use nom::bytes::streaming::tag;
+			use nom::character::streaming::hex_digit1;
+			use nom::combinator::map_res;
+			use nom::number::streaming::hex_u32;
+
+			macro_rules! try_parse {
+				($expr:expr) => {
+					$expr.map_err(|e| e.map(Error::Parser))?
+				};
+			}
+
+			let (input, size) = try_parse!(hex_u32(input));
+			let (input, _) = try_parse!(tag(";")(input));
+
+			let (input, _) = try_parse!(tag("chunk-signature=")(input));
+			let (input, data) = try_parse!(map_res(hex_digit1, hex::decode)(input));
+			let signature = Hash::try_from(&data).ok_or(nom::Err::Failure(Error::BadSignature))?;
+
+			let (input, _) = try_parse!(tag("\r\n")(input));
+
+			let header = Header {
+				size: size as usize,
+				signature,
+			};
+
+			Ok((input, header))
+		}
+	}
+}
+
+#[derive(Debug)]
+pub enum SignedPayloadStreamError {
+	Stream(Error),
+	InvalidSignature,
+	Message(String),
+}
+
+impl SignedPayloadStreamError {
+	fn message(msg: &str) -> Self {
+		SignedPayloadStreamError::Message(msg.into())
+	}
+}
+
+impl From<SignedPayloadStreamError> for Error {
+	fn from(err: SignedPayloadStreamError) -> Self {
+		match err {
+			SignedPayloadStreamError::Stream(e) => e,
+			SignedPayloadStreamError::InvalidSignature => {
+				Error::bad_request("Invalid payload signature")
+			}
+			SignedPayloadStreamError::Message(e) => {
+				Error::bad_request(format!("Chunk format error: {}", e))
+			}
+		}
+	}
+}
+
+impl<I> From<payload::Error<I>> for SignedPayloadStreamError {
+	fn from(err: payload::Error<I>) -> Self {
+		Self::message(err.description())
+	}
+}
+
+impl<I> From<nom::error::Error<I>> for SignedPayloadStreamError {
+	fn from(err: nom::error::Error<I>) -> Self {
+		Self::message(err.code.description())
+	}
+}
+
+struct SignedPayload {
+	header: payload::Header,
+	data: Bytes,
+}
+
+#[pin_project::pin_project]
+pub struct SignedPayloadStream<S>
+where
+	S: Stream<Item = Result<Bytes, Error>>,
+{
+	#[pin]
+	stream: S,
+	buf: bytes::BytesMut,
+	datetime: DateTime<Utc>,
+	scope: String,
+	signing_hmac: HmacSha256,
+	previous_signature: Hash,
+}
+
+impl<S> SignedPayloadStream<S>
+where
+	S: Stream<Item = Result<Bytes, Error>>,
+{
+	pub fn new(
+		stream: S,
+		signing_hmac: HmacSha256,
+		datetime: DateTime<Utc>,
+		scope: &str,
+		seed_signature: Hash,
+	) -> Self {
+		Self {
+			stream,
+			buf: bytes::BytesMut::new(),
+			datetime,
+			scope: scope.into(),
+			signing_hmac,
+			previous_signature: seed_signature,
+		}
+	}
+
+	fn parse_next(input: &[u8]) -> nom::IResult<&[u8], SignedPayload, SignedPayloadStreamError> {
+		use nom::bytes::streaming::{tag, take};
+
+		macro_rules! try_parse {
+			($expr:expr) => {
+				$expr.map_err(nom::Err::convert)?
+			};
+		}
+
+		let (input, header) = try_parse!(payload::Header::parse(input));
+
+		// 0-sized chunk is the last
+		if header.size == 0 {
+			return Ok((
+				input,
+				SignedPayload {
+					header,
+					data: Bytes::new(),
+				},
+			));
+		}
+
+		let (input, data) = try_parse!(take::<_, _, nom::error::Error<_>>(header.size)(input));
+		let (input, _) = try_parse!(tag::<_, _, nom::error::Error<_>>("\r\n")(input));
+
+		let data = Bytes::from(data.to_vec());
+
+		Ok((input, SignedPayload { header, data }))
+	}
+}
+
+impl<S> Stream for SignedPayloadStream<S>
+where
+	S: Stream<Item = Result<Bytes, Error>> + Unpin,
+{
+	type Item = Result<Bytes, SignedPayloadStreamError>;
+
+	fn poll_next(
+		self: Pin<&mut Self>,
+		cx: &mut task::Context<'_>,
+	) -> task::Poll<Option<Self::Item>> {
+		use std::task::Poll;
+
+		let mut this = self.project();
+
+		loop {
+			let (input, payload) = match Self::parse_next(this.buf) {
+				Ok(res) => res,
+				Err(nom::Err::Incomplete(_)) => {
+					match futures::ready!(this.stream.as_mut().poll_next(cx)) {
+						Some(Ok(bytes)) => {
+							this.buf.extend(bytes);
+							continue;
+						}
+						Some(Err(e)) => {
+							return Poll::Ready(Some(Err(SignedPayloadStreamError::Stream(e))))
+						}
+						None => {
+							return Poll::Ready(Some(Err(SignedPayloadStreamError::message(
+								"Unexpected EOF",
+							))));
+						}
+					}
+				}
+				Err(nom::Err::Error(e)) | Err(nom::Err::Failure(e)) => {
+					return Poll::Ready(Some(Err(e)))
+				}
+			};
+
+			// 0-sized chunk is the last
+			if payload.data.is_empty() {
+				return Poll::Ready(None);
+			}
+
+			let data_sha256sum = sha256sum(&payload.data);
+
+			let expected_signature = compute_streaming_payload_signature(
+				this.signing_hmac,
+				*this.datetime,
+				this.scope,
+				*this.previous_signature,
+				data_sha256sum,
+			)
+			.map_err(|e| {
+				SignedPayloadStreamError::Message(format!("Could not build signature: {}", e))
+			})?;
+
+			if payload.header.signature != expected_signature {
+				return Poll::Ready(Some(Err(SignedPayloadStreamError::InvalidSignature)));
+			}
+
+			*this.buf = input.into();
+			*this.previous_signature = payload.header.signature;
+
+			return Poll::Ready(Some(Ok(payload.data)));
+		}
+	}
+
+	fn size_hint(&self) -> (usize, Option<usize>) {
+		self.stream.size_hint()
+	}
+}
+
+#[cfg(test)]
+mod tests {
+	use futures::prelude::*;
+
+	use super::{SignedPayloadStream, SignedPayloadStreamError};
+
+	#[tokio::test]
+	async fn test_interrupted_signed_payload_stream() {
+		use chrono::{DateTime, Utc};
+
+		use garage_util::data::Hash;
+
+		let datetime = DateTime::parse_from_rfc3339("2021-12-13T13:12:42+01:00") // TODO UNIX 0
+			.unwrap()
+			.with_timezone(&Utc);
+		let secret_key = "test";
+		let region = "test";
+		let scope = crate::signature::compute_scope(&datetime, region, "s3");
+		let signing_hmac =
+			crate::signature::signing_hmac(&datetime, secret_key, region, "s3").unwrap();
+
+		let data: &[&[u8]] = &[b"1"];
+		let body = futures::stream::iter(data.iter().map(|block| Ok(block.to_vec().into())));
+
+		let seed_signature = Hash::default();
+
+		let mut stream =
+			SignedPayloadStream::new(body, signing_hmac, datetime, &scope, seed_signature);
+
+		assert!(stream.try_next().await.is_err());
+		match stream.try_next().await {
+			Err(SignedPayloadStreamError::Message(msg)) if msg == "Unexpected EOF" => {}
+			item => panic!(
+				"Unexpected result, expected early EOF error, got {:?}",
+				item
+			),
+		}
+	}
+}