//! *catar* format decoder.
+//!
+//! This module contain the code to decode *catar* archive files.
+use failure::*;
+use super::format_definition::*;
+use crate::tools;
+
+use std::io::{Read, Seek, SeekFrom};
+use std::path::PathBuf;
+
+use std::os::unix::ffi::{OsStrExt, OsStringExt};
+use std::ffi::{OsStr, OsString};
+
+pub struct CaDirectoryEntry {
+ start: u64,
+ end: u64,
+ pub filename: OsString,
+ pub entry: CaFormatEntry,
+}
+
+// This one needs Read+Seek (we may want one without Seek?)
+pub struct CaTarDecoder<'a, R: Read + Seek> {
+ reader: &'a mut R,
+ root_start: u64,
+ root_end: u64,
+}
+
+const HEADER_SIZE: u64 = std::mem::size_of::<CaFormatHeader>() as u64;
+
+impl <'a, R: Read + Seek> CaTarDecoder<'a, R> {
+
+ pub fn new(reader: &'a mut R) -> Result<Self, Error> {
+
+ let root_end = reader.seek(SeekFrom::End(0))?;
+
+ Ok(Self {
+ reader: reader,
+ root_start: 0,
+ root_end: root_end,
+ })
+ }
+
+ pub fn root(&self) -> CaDirectoryEntry {
+ CaDirectoryEntry {
+ start: self.root_start,
+ end: self.root_end,
+ filename: OsString::new(), // Empty
+ entry: CaFormatEntry {
+ feature_flags: 0,
+ mode: 0,
+ flags: 0,
+ uid: 0,
+ gid: 0,
+ mtime: 0,
+ }
+ }
+ }
+
+ fn read_directory_entry(&mut self, start: u64, end: u64) -> Result<CaDirectoryEntry, Error> {
+
+ self.reader.seek(SeekFrom::Start(start))?;
+ let mut buffer = [0u8; HEADER_SIZE as usize];
+ self.reader.read_exact(&mut buffer)?;
+ let head = tools::map_struct::<CaFormatHeader>(&buffer)?;
+
+ if u64::from_le(head.htype) != CA_FORMAT_FILENAME {
+ bail!("wrong filename header type for object [{}..{}]", start, end);
+ }
+
+ let mut name_len = u64::from_le(head.size);
+
+ let entry_start = start + name_len;
+
+ if name_len < (HEADER_SIZE + 2) {
+ bail!("filename size too short for object [{}..{}]", start, end);
+ }
+ name_len -= HEADER_SIZE;
+
+ if name_len > ((libc::FILENAME_MAX as u64) + 1) {
+ bail!("filename too long for object [{}..{}]", start, end);
+ }
+
+ let mut buffer = vec![0u8; name_len as usize];
+ self.reader.read_exact(&mut buffer)?;
+
+ // fixme: check nul termination
+ let last_byte = buffer.pop().unwrap();
+ if last_byte != 0u8 {
+ bail!("filename entry not nul terminated, object [{}..{}]", start, end);
+
+ }
+
+ let filename = std::ffi::OsString::from_vec(buffer);
+
+ let mut buffer = [0u8; HEADER_SIZE as usize];
+ self.reader.read_exact(&mut buffer)?;
+ let head = tools::map_struct::<CaFormatHeader>(&buffer)?;
+
+ if u64::from_le(head.htype) != CA_FORMAT_ENTRY {
+ bail!("wrong entry header type for object [{}..{}]", start, end);
+ }
+
+ const ENTRY_SIZE: u64 = std::mem::size_of::<CaFormatEntry>() as u64;
+
+ let mut entry_len = u64::from_le(head.size);
+ if entry_len != (HEADER_SIZE + ENTRY_SIZE) {
+ bail!("wrong entry header size for object [{}..{}]", start, end);
+ }
+ entry_len -= HEADER_SIZE;
+
+ let mut buffer = [0u8; ENTRY_SIZE as usize];
+ self.reader.read_exact(&mut buffer)?;
+ let entry = tools::map_struct::<CaFormatEntry>(&buffer)?;
+
+ Ok(CaDirectoryEntry {
+ start: entry_start,
+ end: end,
+ filename: filename,
+ entry: CaFormatEntry {
+ feature_flags: u64::from_le(entry.feature_flags),
+ mode: u64::from_le(entry.mode),
+ flags: u64::from_le(entry.flags),
+ uid: u64::from_le(entry.uid),
+ gid: u64::from_le(entry.gid),
+ mtime: u64::from_le(entry.mtime),
+ },
+ })
+ }
+
+ pub fn list_dir(&mut self, dir: &CaDirectoryEntry) -> Result<Vec<CaDirectoryEntry>, Error> {
+
+ const GOODBYE_ITEM_SIZE: u64 = std::mem::size_of::<CaFormatGoodbyeItem>() as u64;
+
+ let start = dir.start;
+ let end = dir.end;
+
+ //println!("list_dir1: {} {}", start, end);
+
+ if (end - start) < (HEADER_SIZE + GOODBYE_ITEM_SIZE) {
+ bail!("detected short object [{}..{}]", start, end);
+ }
+
+ self.reader.seek(SeekFrom::Start(end - GOODBYE_ITEM_SIZE))?;
+ let mut buffer = [0u8; GOODBYE_ITEM_SIZE as usize];
+ self.reader.read_exact(&mut buffer)?;
+
+ let item = tools::map_struct::<CaFormatGoodbyeItem>(&buffer)?;
+
+ if u64::from_le(item.hash) != CA_FORMAT_GOODBYE_TAIL_MARKER {
+ bail!("missing goodbye tail marker for object [{}..{}]", start, end);
+ }
+
+ let goodbye_table_size = u64::from_le(item.size);
+ if goodbye_table_size < (HEADER_SIZE + GOODBYE_ITEM_SIZE) {
+ bail!("short goodbye table size for object [{}..{}]", start, end);
+
+ }
+ let goodbye_inner_size = goodbye_table_size - HEADER_SIZE - GOODBYE_ITEM_SIZE;
+ if (goodbye_inner_size % GOODBYE_ITEM_SIZE) != 0 {
+ bail!("wrong goodbye inner table size for entry [{}..{}]", start, end);
+ }
+
+ let goodbye_start = end - goodbye_table_size;
+
+ if u64::from_le(item.offset) != (goodbye_start - start) {
+ println!("DEBUG: {} {}", u64::from_le(item.offset), goodbye_start - start);
+ bail!("wrong offset in goodbye tail marker for entry [{}..{}]", start, end);
+ }
+
+ self.reader.seek(SeekFrom::Start(goodbye_start))?;
+ let mut buffer = [0u8; HEADER_SIZE as usize];
+ self.reader.read_exact(&mut buffer)?;
+ let head = tools::map_struct::<CaFormatHeader>(&buffer)?;
+
+ if u64::from_le(head.htype) != CA_FORMAT_GOODBYE {
+ bail!("wrong goodbye table header type for entry [{}..{}]", start, end);
+ }
+
+ if u64::from_le(head.size) != goodbye_table_size {
+ bail!("wrong goodbye table size for entry [{}..{}]", start, end);
+ }
+
+ let mut buffer = [0u8; GOODBYE_ITEM_SIZE as usize];
+
+ let mut range_list = Vec::new();
+
+ for i in 0..goodbye_inner_size/GOODBYE_ITEM_SIZE {
+ self.reader.read_exact(&mut buffer)?;
+ let item = tools::map_struct::<CaFormatGoodbyeItem>(&buffer)?;
+ let item_offset = u64::from_le(item.offset);
+ if item_offset > (goodbye_start - start) {
+ bail!("goodbye entry {} offset out of range [{}..{}] {} {} {}",
+ i, start, end, item_offset, goodbye_start, start);
+ }
+ let item_start = goodbye_start - item_offset;
+ let item_hash = u64::from_le(item.hash);
+ let item_end = item_start + u64::from_le(item.size);
+ if item_end > goodbye_start {
+ bail!("goodbye entry {} end out of range [{}..{}]",
+ i, start, end);
+ }
+
+ range_list.push((item_start, item_end));
+ }
+
+ let mut result = vec![];
+
+ for (item_start, item_end) in range_list {
+ let entry = self.read_directory_entry(item_start, item_end)?;
+ //println!("ENTRY: {} {} {:?}", item_start, item_end, entry.filename);
+ result.push(entry);
+ }
+
+ Ok(result)
+ }
+
+ pub fn print_filenames<W: std::io::Write>(
+ &mut self,
+ output: &mut W,
+ prefix: &mut PathBuf,
+ dir: &CaDirectoryEntry,
+ ) -> Result<(), Error> {
+
+ let mut list = self.list_dir(dir)?;
+
+ list.sort_unstable_by(|a, b| a.filename.cmp(&b.filename));
+
+ for item in &list {
+
+ prefix.push(item.filename.clone());
+
+ let mode = item.entry.mode as u32;
+
+ let osstr: &OsStr = prefix.as_ref();
+ output.write(osstr.as_bytes())?;
+ output.write(b"\n")?;
+
+ if (mode & libc::S_IFMT) == libc::S_IFDIR {
+ self.print_filenames(output, prefix, item)?;
+ } else if (mode & libc::S_IFMT) == libc::S_IFREG {
+ } else if (mode & libc::S_IFMT) == libc::S_IFLNK {
+ } else {
+ bail!("unknown item mode/type for {:?}", prefix);
+ }
+
+ prefix.pop();
+ }
+
+ Ok(())
+ }
+}
projects / proxmox-backup.git / commitdiff