garage/src/api/s3/post_object.rs

514 lines
13 KiB
Rust

use std::collections::HashMap;
use std::convert::TryInto;
use std::ops::RangeInclusive;
use std::sync::Arc;
use std::task::{Context, Poll};
use base64::prelude::*;
use bytes::Bytes;
use chrono::{DateTime, Duration, Utc};
use futures::{Stream, StreamExt};
use hyper::header::{self, HeaderMap, HeaderName, HeaderValue};
use hyper::{Body, Request, Response, StatusCode};
use multer::{Constraints, Multipart, SizeLimit};
use serde::Deserialize;
use garage_model::garage::Garage;
use crate::s3::cors::*;
use crate::s3::error::*;
use crate::s3::put::{get_headers, save_stream};
use crate::s3::xml as s3_xml;
use crate::signature::payload::{parse_date, verify_v4};
pub async fn handle_post_object(
garage: Arc<Garage>,
req: Request<Body>,
bucket_name: String,
) -> Result<Response<Body>, Error> {
let boundary = req
.headers()
.get(header::CONTENT_TYPE)
.and_then(|ct| ct.to_str().ok())
.and_then(|ct| multer::parse_boundary(ct).ok())
.ok_or_bad_request("Could not get multipart boundary")?;
// 16k seems plenty for a header. 5G is the max size of a single part, so it seems reasonable
// for a PostObject
let constraints = Constraints::new().size_limit(
SizeLimit::new()
.per_field(16 * 1024)
.for_field("file", 5 * 1024 * 1024 * 1024),
);
let (head, body) = req.into_parts();
let mut multipart = Multipart::with_constraints(body, boundary, constraints);
let mut params = HeaderMap::new();
let field = loop {
let field = if let Some(field) = multipart.next_field().await? {
field
} else {
return Err(Error::bad_request("Request did not contain a file"));
};
let name: HeaderName = if let Some(Ok(name)) = field.name().map(TryInto::try_into) {
name
} else {
continue;
};
if name == "file" {
break field;
}
if let Ok(content) = HeaderValue::from_str(&field.text().await?) {
match name.as_str() {
"tag" => (/* tag need to be reencoded, but we don't support them yet anyway */),
"acl" => {
if params.insert("x-amz-acl", content).is_some() {
return Err(Error::bad_request("Field 'acl' provided more than once"));
}
}
_ => {
if params.insert(&name, content).is_some() {
return Err(Error::bad_request(format!(
"Field '{}' provided more than once",
name
)));
}
}
}
}
};
// Current part is file. Do some checks before handling to PutObject code
let key = params
.get("key")
.ok_or_bad_request("No key was provided")?
.to_str()?;
let credential = params
.get("x-amz-credential")
.ok_or_else(|| Error::forbidden("Garage does not support anonymous access yet"))?
.to_str()?;
let policy = params
.get("policy")
.ok_or_bad_request("No policy was provided")?
.to_str()?;
let signature = params
.get("x-amz-signature")
.ok_or_bad_request("No signature was provided")?
.to_str()?;
let date = params
.get("x-amz-date")
.ok_or_bad_request("No date was provided")?
.to_str()?;
let key = if key.contains("${filename}") {
// if no filename is provided, don't replace. This matches the behavior of AWS.
if let Some(filename) = field.file_name() {
key.replace("${filename}", filename)
} else {
key.to_owned()
}
} else {
key.to_owned()
};
let date = parse_date(date)?;
let api_key = verify_v4(
&garage,
"s3",
credential,
&date,
signature,
policy.as_bytes(),
)
.await?;
let bucket_id = garage
.bucket_helper()
.resolve_bucket(&bucket_name, &api_key)
.await?;
if !api_key.allow_write(&bucket_id) {
return Err(Error::forbidden("Operation is not allowed for this key."));
}
let bucket = garage
.bucket_helper()
.get_existing_bucket(bucket_id)
.await?;
let decoded_policy = BASE64_STANDARD
.decode(policy)
.ok_or_bad_request("Invalid policy")?;
let decoded_policy: Policy =
serde_json::from_slice(&decoded_policy).ok_or_bad_request("Invalid policy")?;
let expiration: DateTime<Utc> = DateTime::parse_from_rfc3339(&decoded_policy.expiration)
.ok_or_bad_request("Invalid expiration date")?
.into();
if Utc::now() - expiration > Duration::zero() {
return Err(Error::bad_request("Expiration date is in the past"));
}
let mut conditions = decoded_policy.into_conditions()?;
for (param_key, value) in params.iter() {
let mut param_key = param_key.to_string();
param_key.make_ascii_lowercase();
match param_key.as_str() {
"policy" | "x-amz-signature" => (), // this is always accepted, as it's required to validate other fields
"content-type" => {
let conds = conditions.params.remove("content-type").ok_or_else(|| {
Error::bad_request(format!("Key '{}' is not allowed in policy", param_key))
})?;
for cond in conds {
let ok = match cond {
Operation::Equal(s) => s.as_str() == value,
Operation::StartsWith(s) => {
value.to_str()?.split(',').all(|v| v.starts_with(&s))
}
};
if !ok {
return Err(Error::bad_request(format!(
"Key '{}' has value not allowed in policy",
param_key
)));
}
}
}
"key" => {
let conds = conditions.params.remove("key").ok_or_else(|| {
Error::bad_request(format!("Key '{}' is not allowed in policy", param_key))
})?;
for cond in conds {
let ok = match cond {
Operation::Equal(s) => s == key,
Operation::StartsWith(s) => key.starts_with(&s),
};
if !ok {
return Err(Error::bad_request(format!(
"Key '{}' has value not allowed in policy",
param_key
)));
}
}
}
_ => {
if param_key.starts_with("x-ignore-") {
// if a x-ignore is provided in policy, it's not removed here, so it will be
// rejected as provided in policy but not in the request. As odd as it is, it's
// how aws seems to behave.
continue;
}
let conds = conditions.params.remove(&param_key).ok_or_else(|| {
Error::bad_request(format!("Key '{}' is not allowed in policy", param_key))
})?;
for cond in conds {
let ok = match cond {
Operation::Equal(s) => s.as_str() == value,
Operation::StartsWith(s) => value.to_str()?.starts_with(s.as_str()),
};
if !ok {
return Err(Error::bad_request(format!(
"Key '{}' has value not allowed in policy",
param_key
)));
}
}
}
}
}
if let Some((param_key, _)) = conditions.params.iter().next() {
return Err(Error::bad_request(format!(
"Key '{}' is required in policy, but no value was provided",
param_key
)));
}
let headers = get_headers(&params)?;
let stream = field.map(|r| r.map_err(Into::into));
let (_, md5) = save_stream(
garage,
headers,
StreamLimiter::new(stream, conditions.content_length),
&bucket,
&key,
None,
None,
)
.await?;
let etag = format!("\"{}\"", md5);
let mut resp = if let Some(mut target) = params
.get("success_action_redirect")
.and_then(|h| h.to_str().ok())
.and_then(|u| url::Url::parse(u).ok())
.filter(|u| u.scheme() == "https" || u.scheme() == "http")
{
target
.query_pairs_mut()
.append_pair("bucket", &bucket_name)
.append_pair("key", &key)
.append_pair("etag", &etag);
let target = target.to_string();
Response::builder()
.status(StatusCode::SEE_OTHER)
.header(header::LOCATION, target.clone())
.header(header::ETAG, etag)
.body(target.into())?
} else {
let path = head
.uri
.path_and_query()
.map(|paq| paq.path().to_string())
.unwrap_or_else(|| "/".to_string());
let authority = head
.headers
.get(header::HOST)
.and_then(|h| h.to_str().ok())
.unwrap_or_default();
let proto = if !authority.is_empty() {
"https://"
} else {
""
};
let url_key: String = form_urlencoded::byte_serialize(key.as_bytes())
.flat_map(str::chars)
.collect();
let location = format!("{}{}{}{}", proto, authority, path, url_key);
let action = params
.get("success_action_status")
.and_then(|h| h.to_str().ok())
.unwrap_or("204");
let builder = Response::builder()
.header(header::LOCATION, location.clone())
.header(header::ETAG, etag.clone());
match action {
"200" => builder.status(StatusCode::OK).body(Body::empty())?,
"201" => {
let xml = s3_xml::PostObject {
xmlns: (),
location: s3_xml::Value(location),
bucket: s3_xml::Value(bucket_name),
key: s3_xml::Value(key),
etag: s3_xml::Value(etag),
};
let body = s3_xml::to_xml_with_header(&xml)?;
builder
.status(StatusCode::CREATED)
.body(Body::from(body.into_bytes()))?
}
_ => builder.status(StatusCode::NO_CONTENT).body(Body::empty())?,
}
};
let matching_cors_rule =
find_matching_cors_rule(&bucket, &Request::from_parts(head, Body::empty()))?;
if let Some(rule) = matching_cors_rule {
add_cors_headers(&mut resp, rule)
.ok_or_internal_error("Invalid bucket CORS configuration")?;
}
Ok(resp)
}
#[derive(Deserialize)]
struct Policy {
expiration: String,
conditions: Vec<PolicyCondition>,
}
impl Policy {
fn into_conditions(self) -> Result<Conditions, Error> {
let mut params = HashMap::<_, Vec<_>>::new();
let mut length = (0, u64::MAX);
for condition in self.conditions {
match condition {
PolicyCondition::Equal(map) => {
if map.len() != 1 {
return Err(Error::bad_request("Invalid policy item"));
}
let (mut k, v) = map.into_iter().next().expect("Size could not be verified");
k.make_ascii_lowercase();
params.entry(k).or_default().push(Operation::Equal(v));
}
PolicyCondition::OtherOp([cond, mut key, value]) => {
if key.remove(0) != '$' {
return Err(Error::bad_request("Invalid policy item"));
}
key.make_ascii_lowercase();
match cond.as_str() {
"eq" => {
params.entry(key).or_default().push(Operation::Equal(value));
}
"starts-with" => {
params
.entry(key)
.or_default()
.push(Operation::StartsWith(value));
}
_ => return Err(Error::bad_request("Invalid policy item")),
}
}
PolicyCondition::SizeRange(key, min, max) => {
if key == "content-length-range" {
length.0 = length.0.max(min);
length.1 = length.1.min(max);
} else {
return Err(Error::bad_request("Invalid policy item"));
}
}
}
}
Ok(Conditions {
params,
content_length: RangeInclusive::new(length.0, length.1),
})
}
}
/// A single condition from a policy
#[derive(Debug, Deserialize)]
#[serde(untagged)]
enum PolicyCondition {
// will contain a single key-value pair
Equal(HashMap<String, String>),
OtherOp([String; 3]),
SizeRange(String, u64, u64),
}
#[derive(Debug)]
struct Conditions {
params: HashMap<String, Vec<Operation>>,
content_length: RangeInclusive<u64>,
}
#[derive(Debug, PartialEq, Eq)]
enum Operation {
Equal(String),
StartsWith(String),
}
struct StreamLimiter<T> {
inner: T,
length: RangeInclusive<u64>,
read: u64,
}
impl<T> StreamLimiter<T> {
fn new(stream: T, length: RangeInclusive<u64>) -> Self {
StreamLimiter {
inner: stream,
length,
read: 0,
}
}
}
impl<T> Stream for StreamLimiter<T>
where
T: Stream<Item = Result<Bytes, Error>> + Unpin,
{
type Item = Result<Bytes, Error>;
fn poll_next(
mut self: std::pin::Pin<&mut Self>,
ctx: &mut Context<'_>,
) -> Poll<Option<Self::Item>> {
let res = std::pin::Pin::new(&mut self.inner).poll_next(ctx);
match &res {
Poll::Ready(Some(Ok(bytes))) => {
self.read += bytes.len() as u64;
// optimization to fail early when we know before the end it's too long
if self.length.end() < &self.read {
return Poll::Ready(Some(Err(Error::bad_request(
"File size does not match policy",
))));
}
}
Poll::Ready(None) => {
if !self.length.contains(&self.read) {
return Poll::Ready(Some(Err(Error::bad_request(
"File size does not match policy",
))));
}
}
_ => {}
}
res
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_policy_1() {
let policy_json = br#"
{ "expiration": "2007-12-01T12:00:00.000Z",
"conditions": [
{"acl": "public-read" },
{"bucket": "johnsmith" },
["starts-with", "$key", "user/eric/"]
]
}
"#;
let policy_2: Policy = serde_json::from_slice(&policy_json[..]).unwrap();
let mut conditions = policy_2.into_conditions().unwrap();
assert_eq!(
conditions.params.remove(&"acl".to_string()),
Some(vec![Operation::Equal("public-read".into())])
);
assert_eq!(
conditions.params.remove(&"bucket".to_string()),
Some(vec![Operation::Equal("johnsmith".into())])
);
assert_eq!(
conditions.params.remove(&"key".to_string()),
Some(vec![Operation::StartsWith("user/eric/".into())])
);
assert!(conditions.params.is_empty());
assert_eq!(conditions.content_length, 0..=u64::MAX);
}
#[test]
fn test_policy_2() {
let policy_json = br#"
{ "expiration": "2007-12-01T12:00:00.000Z",
"conditions": [
[ "eq", "$acl", "public-read" ],
["starts-with", "$Content-Type", "image/"],
["starts-with", "$success_action_redirect", ""],
["content-length-range", 1048576, 10485760]
]
}
"#;
let policy_2: Policy = serde_json::from_slice(&policy_json[..]).unwrap();
let mut conditions = policy_2.into_conditions().unwrap();
assert_eq!(
conditions.params.remove(&"acl".to_string()),
Some(vec![Operation::Equal("public-read".into())])
);
assert_eq!(
conditions.params.remove("content-type").unwrap(),
vec![Operation::StartsWith("image/".into())]
);
assert_eq!(
conditions
.params
.remove(&"success_action_redirect".to_string()),
Some(vec![Operation::StartsWith("".into())])
);
assert!(conditions.params.is_empty());
assert_eq!(conditions.content_length, 1048576..=10485760);
}
}