use crate::{config, file_kind::FileKind}; use actix_multipart::{Field, Multipart}; use actix_web::{error, http::header::DispositionParam, Error}; use async_std::{fs::File, path::Path, prelude::*}; use chrono::{prelude::*, Duration}; use futures::{StreamExt, TryStreamExt}; const MAX_UPLOAD_SECONDS: u64 = 31 * 24 * 60 * 60; const DEFAULT_UPLOAD_SECONDS: u64 = 30 * 60; pub(crate) struct UploadConfig { pub original_name: String, pub valid_till: DateTime, pub kind: FileKind, pub delete_on_download: bool, } pub(crate) async fn parse_multipart( mut payload: Multipart, file_id: &str, file_name: &Path, config: &config::Config, ) -> Result { let mut original_name: Option = None; let mut keep_for: Option = None; let mut kind: Option = None; let mut delete_on_download = false; let mut password = None; let mut size = 0; while let Ok(Some(field)) = payload.try_next().await { let name = get_field_name(&field)?; let name = name.as_str(); match name { "keep_for" => { keep_for = Some(parse_string(name, field).await?); } "file" => { let file_original_name = get_original_filename(&field); if file_original_name == None || file_original_name.as_deref() == Some("") { continue; } original_name = file_original_name; kind = Some(FileKind::Binary); size = create_file(file_name, field, config.max_file_size).await?; } "text" => { if original_name.is_some() { continue; } original_name = Some(format!("{}.txt", file_id)); kind = Some(FileKind::Text); size = create_file(file_name, field, config.max_file_size).await?; } "delete_on_download" => { delete_on_download = parse_string(name, field).await? != "false"; } "password" => { password = Some(parse_string(name, field).await?); } _ => {} }; } let original_name = original_name.ok_or_else(|| error::ErrorBadRequest("no content found"))?; let kind = kind.ok_or_else(|| error::ErrorBadRequest("no content found"))?; if original_name.len() > 255 { return Err(error::ErrorBadRequest("filename is too long")); } let validated_keep_for: u64 = if let Some(keep_for) = keep_for { let seconds = keep_for.parse().map_err(|e| { error::ErrorBadRequest(format!("field keep_for is not a number: {}", e)) })?; if seconds > MAX_UPLOAD_SECONDS { return Err(error::ErrorBadRequest(format!( "maximum allowed validity is {} seconds, but you specified {} seconds", MAX_UPLOAD_SECONDS, seconds ))); } seconds } else { DEFAULT_UPLOAD_SECONDS }; let valid_duration = Duration::seconds(validated_keep_for as i64); let valid_till = Local::now() + valid_duration; check_auth_requirements(size, valid_duration, password, config)?; Ok(UploadConfig { original_name, valid_till, kind, delete_on_download, }) } fn check_auth_requirements( size: u64, validated_keep_for: Duration, password: Option, config: &config::Config, ) -> Result<(), error::Error> { if let Some(no_auth_limits) = &config.no_auth_limits { let requires_auth = validated_keep_for > no_auth_limits.max_time || validated_keep_for > no_auth_limits.large_file_max_time && size > no_auth_limits.large_file_size; if requires_auth && password.as_ref() != Some(&no_auth_limits.auth_password) { return Err(error::ErrorBadRequest( "upload requires authentication, but authentication was incorrect", )); } } Ok(()) } fn get_field_name(field: &Field) -> Result { Ok(field .content_disposition() .ok_or(error::ParseError::Incomplete)? .get_name() .map(|s| s.to_owned()) .ok_or(error::ParseError::Incomplete)?) } async fn parse_string(name: &str, field: actix_multipart::Field) -> Result { let data = read_content(field).await?; String::from_utf8(data) .map_err(|_| error::ErrorBadRequest(format!("could not parse field {} as utf-8", name))) } async fn read_content(mut field: actix_multipart::Field) -> Result, error::Error> { let mut data = Vec::new(); while let Some(chunk) = field.next().await { data.extend(chunk.map_err(error::ErrorBadRequest)?); } Ok(data) } async fn create_file( filename: &Path, field: Field, max_file_size: Option, ) -> Result { let mut file = File::create(&filename).await.map_err(|file_err| { log::error!("could not create file {:?}", file_err); error::ErrorInternalServerError("could not create file") })?; let written_bytes = write_to_file(&mut file, field, max_file_size).await?; Ok(written_bytes) } async fn write_to_file( file: &mut File, mut field: Field, max_size: Option, ) -> Result { let mut written_bytes: u64 = 0; while let Some(chunk) = field.next().await { let chunk = chunk.map_err(error::ErrorBadRequest)?; written_bytes += chunk.len() as u64; if let Some(max_size) = max_size { if written_bytes > max_size { return Err(error::ErrorBadRequest(format!( "exceeded maximum file size of {} bytes", max_size ))); } } file.write_all(chunk.as_ref()).await.map_err(|write_err| { log::error!("could not write file {:?}", write_err); error::ErrorInternalServerError("could not write file") })?; } Ok(written_bytes) } fn get_original_filename(field: &actix_multipart::Field) -> Option { field.content_disposition().and_then(|content_disposition| { content_disposition .parameters .into_iter() .find_map(|param| match param { DispositionParam::Filename(filename) => Some(filename), _ => None, }) }) }