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::{verify_v4, Authorization}; pub async fn handle_post_object( garage: Arc, req: Request, bucket_name: String, ) -> Result, 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 policy = params .get("policy") .ok_or_bad_request("No policy was provided")? .to_str()?; let authorization = Authorization::parse_form(¶ms)?; 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 api_key = verify_v4(&garage, "s3", &authorization, 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 = 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(¶m_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(¶ms)?; 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, } impl Policy { fn into_conditions(self) -> Result { 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), OtherOp([String; 3]), SizeRange(String, u64, u64), } #[derive(Debug)] struct Conditions { params: HashMap>, content_length: RangeInclusive, } #[derive(Debug, PartialEq, Eq)] enum Operation { Equal(String), StartsWith(String), } struct StreamLimiter { inner: T, length: RangeInclusive, read: u64, } impl StreamLimiter { fn new(stream: T, length: RangeInclusive) -> Self { StreamLimiter { inner: stream, length, read: 0, } } } impl Stream for StreamLimiter where T: Stream> + Unpin, { type Item = Result; fn poll_next( mut self: std::pin::Pin<&mut Self>, ctx: &mut Context<'_>, ) -> Poll> { 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); } }