give zipped files a containing directory to unzip into

src/download.rs

@@ -96,7 +96,7 @@ impl DownloadingFile {
     fn selected(&self) -> Option<&UploadedFile> {
         match self.selection {
             DownloadSelection::All => None,
-            DownloadSelection::One(n) => Some(self.info.contents.as_ref()?.get(n)?),
+            DownloadSelection::One(n) => Some(self.info.contents.as_ref()?.files.get(n)?),
         }
     }
 

src/main.rs

@@ -114,7 +114,7 @@ async fn handle_download(
     if let Some(selection) = query.download {
         if let download::DownloadSelection::One(n) = selection {
             if let Some(ref files) = info.contents {
-                if n >= files.len() {
+                if n >= files.files.len() {
                     return not_found(req, data, false);
                 }
             } else {
@@ -129,7 +129,7 @@ async fn handle_download(
         }
         .into_response(&req))
     } else {
-        let offsets = info.contents.as_deref().map(zip::file_data_offsets);
+        let offsets = info.contents.as_ref().map(zip::file_data_offsets);
         Ok(DownloadPage {
             info: DownloadInfo {
                 file: info,
@@ -167,7 +167,7 @@ async fn download_info(
     };
 
     let storage_path = data.config.storage_dir.join(code);
-    let offsets = info.contents.as_deref().map(zip::file_data_offsets);
+    let offsets = info.contents.as_ref().map(zip::file_data_offsets);
     Ok(web::Json(DownloadInfo {
         file: info,
         code: code.clone(),

src/store.rs

@@ -11,6 +11,7 @@ use rand::{
 };
 use serde::{Deserialize, Serialize};
 use serde_with::skip_serializing_none;
+use serde_with::{serde_as, PickFirst, FromInto};
 use time::OffsetDateTime;
 use tokio::{
     fs::File,
@@ -18,6 +19,7 @@ use tokio::{
 };
 
 use crate::upload::UploadedFile;
+use crate::zip::FileSet;
 
 const STATE_FILE_NAME: &str = "files.json";
 const MAX_STORAGE_FILES: usize = 1024;
@@ -36,6 +38,7 @@ pub fn is_valid_storage_code(s: &str) -> bool {
         .all(|c| c.is_ascii_alphanumeric() || c == &b'-')
 }
 
+#[serde_as]
 #[skip_serializing_none]
 #[derive(Clone, Deserialize, Serialize)]
 pub struct StoredFile {
@@ -45,7 +48,9 @@ pub struct StoredFile {
     pub modtime: OffsetDateTime,
     #[serde(with = "crate::timestamp")]
     pub expiry: OffsetDateTime,
-    pub contents: Option<Vec<UploadedFile>>,
+    #[serde_as(as = "Option<PickFirst<(_, FromInto<Vec<UploadedFile>>)>>")]
+    #[serde(default)]
+    pub contents: Option<FileSet>,
 }
 
 async fn is_valid_entry(key: &str, info: &StoredFile, storage_dir: &Path) -> bool {

src/upload.rs

@@ -6,6 +6,7 @@ use actix_web::web;
 use actix_web_actors::ws::{self, CloseCode};
 use bytes::Bytes;
 use log::{debug, error, info, trace};
+use sanitise_file_name::{sanitise_with_options, Options as SanOptions};
 use serde::{Deserialize, Serialize};
 use time::OffsetDateTime;
 use unicode_normalization::UnicodeNormalization;
@@ -13,6 +14,7 @@ use unicode_normalization::UnicodeNormalization;
 use crate::{
     log_auth_failure,
     store::{self, FileAddError, StoredFile},
+    zip::FileSet,
     AppState,
 };
 
@@ -20,8 +22,18 @@ const MAX_FILES: usize = 256;
 const FILENAME_DATE_FORMAT: &[time::format_description::FormatItem] =
     time::macros::format_description!("[year]-[month]-[day]-[hour][minute][second]");
 
-fn sanitise(name: &str) -> String {
+/// Sanitises a filename after performing unicode normalization,
-    sanitise_file_name::sanitise(&name.nfd().collect::<String>())
+/// optionally reducing the length limit to leave space for an
+/// extension yet to be added.
+fn sanitise(name: &str, extension_length: usize) -> String {
+    let name = name.nfd().collect::<String>();
+    sanitise_with_options(
+        &name,
+        &SanOptions {
+            length_limit: SanOptions::DEFAULT.length_limit - extension_length,
+            ..SanOptions::DEFAULT
+        },
+    )
 }
 
 #[derive(thiserror::Error, Debug)]
@@ -108,7 +120,7 @@ pub struct UploadedFile {
 impl UploadedFile {
     fn new(name: &str, size: u64, modtime: OffsetDateTime) -> Self {
         Self {
-            name: sanitise(name),
+            name: sanitise(name, 0),
             size,
             modtime,
         }
@@ -256,7 +268,7 @@ impl Uploader {
                     let mut file = raw_file.process();
                     while filenames.contains(&file.name) {
                         info!("Duplicate file name: {}", file.name);
-                        if file.name.len() >= sanitise_file_name::Options::DEFAULT.length_limit {
+                        if file.name.len() >= SanOptions::DEFAULT.length_limit {
                             return Err(Error::DuplicateFilename);
                         }
                         file.name.insert(0, '_');
@@ -278,25 +290,28 @@ impl Uploader {
                     .write(true)
                     .create_new(true)
                     .open(&storage_path)?;
-                let (writer, name, size, modtime): (Box<dyn Write>, _, _, _) = if files.len() > 1 {
+                let (writer, name, size, modtime, contents): (Box<dyn Write>, _, _, _, _) = if files.len() > 1 {
                     info!("Wrapping in zipfile generator");
                     let now = OffsetDateTime::now_utc();
-                    let zip_writer = super::zip::ZipGenerator::new(files.clone(), writer);
+                    let collection_name =
-                    let size = zip_writer.total_size();
+                        collection_name.map(|f| sanitise(&f, 4)).unwrap_or_else(|| {
-                    let download_filename = collection_name
+                            super::APP_NAME.to_owned() + &now.format(FILENAME_DATE_FORMAT).unwrap()
-                        .map(|f| sanitise(&(f + ".zip")))
-                        .unwrap_or_else(|| {
-                            super::APP_NAME.to_owned()
-                                + &now.format(FILENAME_DATE_FORMAT).unwrap()
-                                + ".zip"
                         });
-                    (Box::new(zip_writer), download_filename, size, now)
+                    let file_set = FileSet {
+                        files,
+                        directory_name: Some(collection_name.clone()),
+                    };
+                    let zip_writer =
+                        super::zip::ZipGenerator::new(file_set.clone(), writer);
+                    let size = zip_writer.total_size();
+                    (Box::new(zip_writer), collection_name + ".zip", size, now, Some(file_set))
                 } else {
                     (
                         Box::new(writer),
                         files[0].name.clone(),
                         files[0].size,
                         files[0].modtime,
+                        None
                     )
                 };
                 self.writer = Some(writer);
@@ -305,7 +320,7 @@ impl Uploader {
                     size,
                     modtime,
                     expiry: OffsetDateTime::now_utc() + lifetime * time::Duration::DAY,
-                    contents: if files.len() > 1 { Some(files) } else { None },
+                    contents,
                 };
                 let state = self.app_state.clone();
                 let storage_filename = self.storage_filename.clone();

src/zip.rs

@@ -2,10 +2,13 @@ use std::io::Write;
 
 use crc32fast::Hasher;
 use log::debug;
+use serde::{Deserialize, Serialize};
 use time::OffsetDateTime;
 
 use crate::upload::UploadedFile;
 
+const SLASH: u8 = 0x2f;
+
 const SIGNATURE_SIZE: u64 = 4;
 const SHARED_FIELDS_SIZE: u64 = 26;
 const EXTRA_FIELD_SIZE: u64 = 41;
@@ -25,45 +28,67 @@ const EOCD_TOTAL_SIZE: u64 = EOCD64_RECORD_SIZE + EOCD64_LOCATOR_SIZE + EOCD_REC
 
 const EMPTY_STRING_CRC32: u32 = 0;
 
-fn file_entry_size(file: &UploadedFile) -> u64 {
+#[derive(Clone, Deserialize, Serialize)]
-    FILE_ENTRY_SIZE_MINUS_FILENAME_AND_FILE + file.name.len() as u64 + file.size
+pub struct FileSet {
+    pub files: Vec<UploadedFile>,
+    // Optional for backwards compatibility only
+    pub directory_name: Option<String>,
 }
 
-fn file_entries_size(files: &[UploadedFile]) -> u64 {
+impl From<Vec<UploadedFile>> for FileSet {
+    fn from(files: Vec<UploadedFile>) -> Self {
+        Self { files, directory_name: None }
+    }
+}
+
+fn full_file_name_len(file: &UploadedFile, directory_name: &Option<String>) -> u64 {
+    file.name.len() as u64 + if let Some(d) = directory_name {
+        d.len() as u64 + 1
+    } else {
+        0
+    }
+}
+
+fn file_entry_size(file: &UploadedFile, directory_name: &Option<String>) -> u64 {
+    FILE_ENTRY_SIZE_MINUS_FILENAME_AND_FILE + full_file_name_len(file, directory_name) + file.size
+}
+
+fn file_entries_size(files: &FileSet, bound: Option<usize>) -> u64 {
     let mut total = 0;
-    for file in files.iter() {
+    let fs = if let Some(n) = bound { &files.files[..n] } else { &files.files };
-        total += file_entry_size(file)
+    for file in fs.iter() {
+        total += file_entry_size(file, &files.directory_name)
     }
     total
 }
 
-pub fn file_data_offset(files: &[UploadedFile], idx: usize) -> u64 {
+pub fn file_data_offset(files: &FileSet, idx: usize) -> u64 {
-    file_entries_size(&files[..idx])
+    file_entries_size(files, Some(idx))
         + LOCAL_HEADER_SIZE_MINUS_FILENAME
-        + files[idx].name.len() as u64
+        + full_file_name_len(&files.files[idx], &files.directory_name)
 }
 
-pub fn file_data_offsets(files: &[UploadedFile]) -> Vec<u64> {
+pub fn file_data_offsets(files: &FileSet) -> Vec<u64> {
     let mut offsets = Vec::new();
     let mut offset: u64 = 0;
-    for file in files.iter() {
+    for file in files.files.iter() {
-        offset += LOCAL_HEADER_SIZE_MINUS_FILENAME + file.name.len() as u64;
+        offset += LOCAL_HEADER_SIZE_MINUS_FILENAME + full_file_name_len(file, &files.directory_name);
         offsets.push(offset);
         offset += file.size + DATA_DESCRIPTOR_SIZE;
     }
     offsets
 }
 
-fn central_directory_size(files: &[UploadedFile]) -> u64 {
+fn central_directory_size(files: &FileSet) -> u64 {
     let mut total = 0;
-    for file in files.iter() {
+    for file in files.files.iter() {
-        total += CENTRAL_DIRECTORY_HEADER_SIZE_MINUS_FILENAME + file.name.len() as u64;
+        total += CENTRAL_DIRECTORY_HEADER_SIZE_MINUS_FILENAME + full_file_name_len(file, &files.directory_name);
     }
     total
 }
 
-fn zipfile_size(files: &[UploadedFile]) -> u64 {
+fn zipfile_size(files: &FileSet) -> u64 {
-    file_entries_size(files) + central_directory_size(files) + EOCD_TOTAL_SIZE
+    file_entries_size(files, None) + central_directory_size(files) + EOCD_TOTAL_SIZE
 }
 
 fn fat_timestamp(time: OffsetDateTime) -> u32 {
@@ -100,7 +125,7 @@ impl UploadedFile {
     /// Returns the fields shared by the ZIP local file header and
     /// central directory file header - "Version needed to extract"
     /// through "Extra field length".
-    fn shared_header_fields(&self, hash: Option<u32>) -> Vec<u8> {
+    fn shared_header_fields(&self, directory_name: &Option<String>, hash: Option<u32>) -> Vec<u8> {
         let mut fields = vec![
             45, 0,          // Minimum version required to extract: 4.5 for ZIP64
             0b00001000, // General purpose bit flag: bit 3 - size and CRC-32 in data descriptor
@@ -112,7 +137,7 @@ impl UploadedFile {
         append_value(&mut fields, hash.unwrap_or(0) as u64, 4);
         // Placeholders for compressed and uncompressed size in ZIP64 record, 4 bytes each
         append_ff(&mut fields, 8);
-        append_value(&mut fields, self.name.len() as u64, 2);
+        append_value(&mut fields, full_file_name_len(self, directory_name), 2);
         // Extra field length: 32 bytes for zip64, 9 bytes for timestamp
         fields.append(&mut vec![41, 0]);
         fields
@@ -142,24 +167,34 @@ impl UploadedFile {
         field
     }
 
-    fn local_header(&self, local_header_offset: u64) -> Vec<u8> {
+    fn full_name_bytes(&self, directory_name: &Option<String>) -> Vec<u8> {
+        let mut b = vec![];
+        if let Some(d) = directory_name {
+            b.append(&mut d.to_owned().into_bytes());
+            b.push(SLASH);
+        }
+        b.append(&mut self.name.clone().into_bytes());
+        b
+    }
+
+    fn local_header(&self, directory_name: &Option<String>, local_header_offset: u64) -> Vec<u8> {
         let mut header = vec![0x50, 0x4b, 0x03, 0x04]; // Local file header signature
-        header.append(&mut self.shared_header_fields(None));
+        header.append(&mut self.shared_header_fields(directory_name, None));
-        header.append(&mut self.name.clone().into_bytes());
+        header.append(&mut self.full_name_bytes(directory_name));
         header.append(&mut self.extra_field(local_header_offset));
         header
     }
 
-    fn central_directory_header(&self, local_header_offset: u64, hash: u32) -> Vec<u8> {
+    fn central_directory_header(&self, directory_name: &Option<String>, local_header_offset: u64, hash: u32) -> Vec<u8> {
         let mut header = vec![
             0x50, 0x4b, 0x01, 0x02, // Central directory file header signature
             45, 3, // Made by a Unix system supporting version 4.5
         ];
-        header.append(&mut self.shared_header_fields(Some(hash)));
+        header.append(&mut self.shared_header_fields(directory_name, Some(hash)));
         append_0(&mut header, 8); // Comment length, disk number, internal attributes, DOS external attributes
         append_value(&mut header, 0o100644, 2); // Unix external file attributes: -rw-r--r--
         append_ff(&mut header, 4); // Relative offset of local file header: placeholder, see ZIP64 data
-        header.append(&mut self.name.clone().into_bytes());
+        header.append(&mut self.full_name_bytes(directory_name));
         header.append(&mut self.extra_field(local_header_offset));
         header
     }
@@ -174,8 +209,8 @@ impl UploadedFile {
     }
 }
 
-fn end_of_central_directory(files: &[UploadedFile]) -> Vec<u8> {
+fn end_of_central_directory(files: &FileSet) -> Vec<u8> {
-    let entries_size = file_entries_size(files);
+    let entries_size = file_entries_size(files, None);
     let directory_size = central_directory_size(files);
 
     let mut eocd = vec![
@@ -188,9 +223,10 @@ fn end_of_central_directory(files: &[UploadedFile]) -> Vec<u8> {
         45, 0, // Minimum version 4.5 to extract
     ]);
     append_0(&mut eocd, 8); // Two 4-byte disk numbers, both 0
-                            // Number of central directory records, on this disk and in total
+
-    append_value(&mut eocd, files.len() as u64, 8);
+    // Number of central directory records, on this disk and in total
-    append_value(&mut eocd, files.len() as u64, 8);
+    append_value(&mut eocd, files.files.len() as u64, 8);
+    append_value(&mut eocd, files.files.len() as u64, 8);
     append_value(&mut eocd, directory_size, 8);
     append_value(&mut eocd, entries_size, 8); // Offset of start of central directory
 
@@ -207,7 +243,7 @@ fn end_of_central_directory(files: &[UploadedFile]) -> Vec<u8> {
 }
 
 pub struct ZipGenerator<W: Write> {
-    files: Vec<UploadedFile>,
+    files: FileSet,
     file_index: usize,
     byte_index: u64,
     pending_metadata: Vec<u8>,
@@ -217,7 +253,7 @@ pub struct ZipGenerator<W: Write> {
 }
 
 impl<W: Write> ZipGenerator<W> {
-    pub fn new(files: Vec<UploadedFile>, output: W) -> Self {
+    pub fn new(files: FileSet, output: W) -> Self {
         let mut result = Self {
             files,
             file_index: 0,
@@ -239,39 +275,39 @@ impl<W: Write> ZipGenerator<W> {
         let hash = std::mem::replace(&mut self.hasher, Hasher::new()).finalize();
         self.hashes.push(hash);
         self.pending_metadata
-            .append(&mut self.files[self.file_index].data_descriptor(hash));
+            .append(&mut self.files.files[self.file_index].data_descriptor(hash));
         debug!(
             "Finishing file entry in zipfile: {}, hash {:x}",
-            self.files[self.file_index].name, hash
+            self.files.files[self.file_index].name, hash
         );
         self.file_index += 1;
         self.start_new_file();
     }
 
     fn start_new_file(&mut self) {
-        let mut offset = file_entries_size(&self.files[..self.file_index]);
+        let mut offset = file_entries_size(&self.files, Some(self.file_index));
-        while self.file_index < self.files.len() && self.files[self.file_index].size == 0 {
+        while self.file_index < self.files.files.len() && self.files.files[self.file_index].size == 0 {
             debug!(
                 "Empty file entry in zipfile: {}",
-                self.files[self.file_index].name
+                self.files.files[self.file_index].name
             );
             self.hashes.push(EMPTY_STRING_CRC32);
-            let mut local_header = self.files[self.file_index].local_header(offset);
+            let mut local_header = self.files.files[self.file_index].local_header(&self.files.directory_name, offset);
             let mut data_descriptor =
-                self.files[self.file_index].data_descriptor(EMPTY_STRING_CRC32);
+                self.files.files[self.file_index].data_descriptor(EMPTY_STRING_CRC32);
             offset += local_header.len() as u64 + data_descriptor.len() as u64;
             self.file_index += 1;
             self.pending_metadata.append(&mut local_header);
             self.pending_metadata.append(&mut data_descriptor);
         }
-        if self.file_index < self.files.len() {
+        if self.file_index < self.files.files.len() {
             debug!(
                 "Starting file entry in zipfile: {}",
-                self.files[self.file_index].name
+                self.files.files[self.file_index].name
             );
             self.byte_index = 0;
             self.pending_metadata
-                .append(&mut self.files[self.file_index].local_header(offset));
+                .append(&mut self.files.files[self.file_index].local_header(&self.files.directory_name, offset));
         } else {
             self.finish_zipfile();
         }
@@ -280,14 +316,14 @@ impl<W: Write> ZipGenerator<W> {
     fn finish_zipfile(&mut self) {
         debug!("Writing zipfile central directory");
         let mut offset = 0;
-        for (i, file) in self.files.iter().enumerate() {
+        for (i, file) in self.files.files.iter().enumerate() {
             debug!(
                 "Writing central directory entry: {}, hash {}",
                 file.name, self.hashes[i]
             );
             self.pending_metadata
-                .append(&mut file.central_directory_header(offset, self.hashes[i]));
+                .append(&mut file.central_directory_header(&self.files.directory_name, offset, self.hashes[i]));
-            offset += file_entry_size(file);
+            offset += file_entry_size(file, &self.files.directory_name);
         }
         debug!("Writing end of central directory");
         self.pending_metadata
@@ -308,10 +344,10 @@ impl<W: Write> Write for ZipGenerator<W> {
                 }
             }
         }
-        if self.file_index >= self.files.len() {
+        if self.file_index >= self.files.files.len() {
             return Ok(0);
         }
-        let bytes_remaining = self.files[self.file_index].size - self.byte_index;
+        let bytes_remaining = self.files.files[self.file_index].size - self.byte_index;
         if bytes_remaining < (buf.len() as u64) {
             buf = &buf[..bytes_remaining as usize];
         }
@@ -347,7 +383,8 @@ mod tests {
     fn test_no_files() {
         let mut output: Vec<u8> = vec![];
         {
-            let mut zipgen = ZipGenerator::new(vec![], Box::new(std::io::Cursor::new(&mut output)));
+            let mut zipgen =
+                ZipGenerator::new(FileSet { files: vec![], directory_name: "test".to_owned() }, Box::new(std::io::Cursor::new(&mut output)));
             zipgen.write_all(&[]).unwrap();
             zipgen.flush().unwrap();
         }

templates/download.html

@@ -7,7 +7,7 @@
   {% let formatted_total_size = bytesize::to_string(info.file.size.clone(), false).replace(" ", "") -%}
   {% match info.file.contents -%}
     {% when Some with (files) -%}
-      {{ files.len() }} files, {{ formatted_total_size }} total
+      {{ files.files.len() }} files, {{ formatted_total_size }} total
     {%- else -%}
       {{ formatted_total_size }}
     {%- endmatch %}, expires {{ info.file.expiry.format(DATE_DISPLAY_FORMAT).unwrap() }}
@@ -37,7 +37,7 @@
           <summary>Show file list</summary>
           <table><tbody>
             {% let offsets = info.offsets.as_ref().unwrap() %}
-            {% for f in files %}
+            {% for f in files.files %}
               <tr class="{% if offsets.get(loop.index0.clone()).unwrap().clone() > info.available %}unavailable{% endif %}">
                 <td class="file_size">{{ bytesize::to_string(f.size.clone(), false).replace(" ", "") }}</td>
                 <td class="file_name">{{ f.name }}</td>