Files
drawer/src/parsing.rs
T
2026-05-11 20:44:14 -05:00

427 lines
15 KiB
Rust

use std::ffi::OsString;
use std::io::Write;
use std::path::{Path, PathBuf};
use age::ssh::Identity;
use flate2::Compression;
use flate2::read::GzDecoder;
use flate2::write::GzEncoder;
use clap::{Parser, Subcommand};
use ssh_key::{Algorithm, LineEnding, PrivateKey};
use crate::error::DrawerError;
use crate::parsing::KeyType::*;
#[derive(Debug, Copy, Clone, PartialEq)]
pub enum OperationType {
Open,
Close,
Key,
Info,
}
#[derive(Debug, PartialEq)]
pub struct DrawerOperation {
pub operation_type: OperationType,
pub drawer_file: PathBuf,
pub key: KeyType,
pub target_path: Option<PathBuf>,
pub force: bool,
}
#[derive(Debug, PartialEq)]
pub enum KeyType {
EnvVar, Path(PathBuf)
}
#[derive(Parser)]
#[command(name = "drawer", about = "Encrypt and decrypt project directories as drawer files")]
struct Cli {
#[command(subcommand)]
command: Command,
}
#[derive(Subcommand)]
enum Command {
/// Decrypt and expand a drawer file into a directory
Open {
drawer_file: PathBuf,
target_path: Option<PathBuf>,
#[arg(short = 'i')]
key: Option<PathBuf>,
#[arg(short = 'f')]
force: bool,
},
/// Compress and encrypt a directory into a drawer file
Close {
drawer_file: PathBuf,
target_path: Option<PathBuf>,
#[arg(short = 'i')]
key: Option<PathBuf>,
},
/// Generate a new SSH key and save it to a file
Key {
filename: PathBuf,
},
/// Show information about a drawer file
Info {
drawer_file: PathBuf,
#[arg(short = 'i')]
key: Option<PathBuf>,
},
}
pub fn parse_args<I, T>(args: I) -> Result<DrawerOperation, DrawerError>
where
I: IntoIterator<Item = T>,
T: Into<OsString> + Clone,
{
let cli = Cli::try_parse_from(args)
.map_err(|e| DrawerError::ParseError(e.to_string()))?;
match cli.command {
Command::Open { drawer_file, target_path, key, force } => {
let key = resolve_key(key);
Ok(DrawerOperation {
operation_type: OperationType::Open,
drawer_file,
key,
target_path,
force,
})
}
Command::Close { drawer_file, target_path, key } => {
let key = resolve_key(key);
Ok(DrawerOperation {
operation_type: OperationType::Close,
drawer_file,
key,
target_path,
force: false,
})
}
Command::Key { filename } => {
Ok(DrawerOperation {
operation_type: OperationType::Key,
drawer_file: filename,
key: KeyType::EnvVar,
target_path: None,
force: false,
})
}
Command::Info { drawer_file, key } => {
let key = resolve_key(key);
Ok(DrawerOperation {
operation_type: OperationType::Info,
drawer_file,
key,
target_path: None,
force: false,
})
}
}
}
fn resolve_key(key: Option<PathBuf>) -> KeyType {
if let Some(k) = key {
return Path(k);
}
EnvVar
}
enum ArchiveInfo {
SingleFile { size: u64 },
Folder { file_count: usize },
}
fn archive_info(data: &[u8]) -> Result<ArchiveInfo, DrawerError> {
let cursor = std::io::Cursor::new(data);
let gz = GzDecoder::new(cursor);
let mut archive = tar::Archive::new(gz);
let mut entries = archive.entries().map_err(|_| DrawerError::UntarFailed)?;
let first = entries.next()
.ok_or(DrawerError::UntarFailed)?
.map_err(|_| DrawerError::UntarFailed)?;
if first.header().entry_type().is_file() {
let size = first.header().size().map_err(|_| DrawerError::UntarFailed)?;
if entries.next().is_none() {
return Ok(ArchiveInfo::SingleFile { size });
}
}
let cursor = std::io::Cursor::new(data);
let gz = GzDecoder::new(cursor);
let mut archive = tar::Archive::new(gz);
let file_count = archive.entries()
.map_err(|_| DrawerError::UntarFailed)?
.filter_map(|e| e.ok())
.filter(|e| e.header().entry_type().is_file())
.count();
Ok(ArchiveInfo::Folder { file_count })
}
fn single_file_entry(data: &[u8]) -> Option<PathBuf> {
let cursor = std::io::Cursor::new(data);
let gz = GzDecoder::new(cursor);
let mut archive = tar::Archive::new(gz);
let mut entries = archive.entries().ok()?;
let entry = entries.next()?.ok()?;
if !entry.header().entry_type().is_file() {
return None;
}
if entries.next().is_some() {
return None;
}
Some(entry.path().ok()?.into_owned())
}
impl DrawerOperation {
// Returns the default target when no target_path is specified.
// For close and for directory drawers on open: the drawer file stem.
// For single-file drawers on open: the filename stored in the archive.
fn default_target(&self, single_file: Option<&std::path::Path>) -> PathBuf {
match single_file {
Some(p) => PathBuf::from(p.file_name().unwrap_or_default()),
None => PathBuf::from(self.drawer_file.file_stem().unwrap_or_default()),
}
}
pub fn perform(&self) -> Result<(), DrawerError> {
self.validate()?;
match self.operation_type {
OperationType::Open => self.perform_open(),
OperationType::Close => self.perform_close(),
OperationType::Key => self.perform_key(),
OperationType::Info => self.perform_info(),
}
}
fn perform_open(&self) -> Result<(), DrawerError> {
let encrypted = std::fs::read(&self.drawer_file)
.map_err(|_| DrawerError::DrawerFileNotFound(self.drawer_file.clone()))?;
let decrypted = self.decrypt(encrypted)?;
let sf = single_file_entry(&decrypted);
let target = self.target_path.as_ref().cloned()
.unwrap_or_else(|| self.default_target(sf.as_deref()));
if self.target_path.is_none() {
println!("(assuming into {})", target.display());
}
if !self.force && target.exists() {
if target.is_file() {
return Err(DrawerError::TargetNotEmpty(target.clone()));
}
let mut entries = std::fs::read_dir(&target)
.map_err(|_| DrawerError::TargetInvalid(target.clone()))?;
if entries.next().is_some() {
return Err(DrawerError::TargetNotEmpty(target.clone()));
}
}
if sf.is_some() {
let cursor = std::io::Cursor::new(&decrypted);
let gz = GzDecoder::new(cursor);
let mut archive = tar::Archive::new(gz);
let mut entry = archive.entries()
.map_err(|_| DrawerError::UntarFailed)?
.next()
.ok_or(DrawerError::UntarFailed)?
.map_err(|_| DrawerError::UntarFailed)?;
entry.unpack(&target).map_err(|_| DrawerError::UntarFailed)?;
} else {
let cursor = std::io::Cursor::new(decrypted);
let gz = GzDecoder::new(cursor);
let mut archive = tar::Archive::new(gz);
archive.unpack(&target).map_err(|_| DrawerError::UntarFailed)?;
}
Ok(())
}
fn decrypt(&self, encrypted: Vec<u8>) -> Result<Vec<u8>, DrawerError> {
let (key_path, identity) = self.identity()?;
let decryptor = age::Decryptor::new(encrypted.as_slice())
.map_err(|_| DrawerError::DecryptFailed(self.drawer_file.clone(), key_path.clone()))?;
let mut decrypted: Vec<u8> = Vec::new();
let mut stream = decryptor.decrypt(std::iter::once(&identity as &dyn age::Identity))
.map_err(|_| DrawerError::DecryptFailed(self.drawer_file.clone(), key_path.clone()))?;
std::io::Read::read_to_end(&mut stream, &mut decrypted)
.map_err(|_| DrawerError::DecryptFailed(self.drawer_file.clone(), key_path.clone()))?;
Ok(decrypted)
}
fn identity(&self) -> Result<(PathBuf, Identity), DrawerError> {
let key_path = self.key_path()?;
let file = std::fs::File::open(&key_path)
.map_err(|_| DrawerError::KeyInvalid(key_path.clone()))?;
let reader = std::io::BufReader::new(file);
let identity = age::ssh::Identity::from_buffer(reader, None)
.map_err(|_| DrawerError::DecryptFailed(self.drawer_file.clone(), key_path.clone()))?;
Ok((key_path, identity))
}
fn perform_close(&self) -> Result<(), DrawerError> {
let target = self.target_path.as_ref().cloned()
.unwrap_or_else(|| self.default_target(None));
let mut buf: Vec<u8> = Vec::new();
{
let gz = GzEncoder::new(&mut buf, Compression::default());
let mut archive = tar::Builder::new(gz);
if target.is_dir() {
archive.append_dir_all(".", &target)
.map_err(|_| DrawerError::TarFailed)?;
} else {
let name = target.file_name().unwrap_or_default();
archive.append_path_with_name(&target, name)
.map_err(|_| DrawerError::TarFailed)?;
}
let gz = archive.into_inner()
.map_err(|_| DrawerError::TarFailed)?;
gz.finish()
.map_err(|_| DrawerError::TarFailed)?;
}
let encrypted = self.encrypt(&buf)?;
std::fs::write(&self.drawer_file, &encrypted)
.map_err(|_| DrawerError::WriteFailed(self.drawer_file.clone()))
}
fn encrypt(&self, buf: &[u8]) -> Result<Vec<u8>, DrawerError> {
let (_, identity) = self.identity()?;
let recipient = age::ssh::Recipient::try_from(identity)
.map_err(|_| DrawerError::EncryptFailed)?;
let mut encrypted: Vec<u8> = Vec::new();
let encryptor = age::Encryptor::with_recipients(
std::iter::once(&recipient as &dyn age::Recipient)
).map_err(|_| DrawerError::EncryptFailed)?;
let mut writer = encryptor.wrap_output(&mut encrypted)
.map_err(|_| DrawerError::EncryptFailed)?;
writer.write_all(buf).map_err(|_| DrawerError::EncryptFailed)?;
writer.finish().map_err(|_| DrawerError::EncryptFailed)?;
Ok(encrypted)
}
pub fn validate(&self) -> Result<(), DrawerError> {
if self.operation_type != OperationType::Key {
if self.drawer_file.extension().and_then(|e| e.to_str()) != Some("drawer") {
return Err(DrawerError::DrawerFileInvalidExtension(self.drawer_file.clone()));
}
self.validate_key()?;
}
match self.operation_type {
OperationType::Open | OperationType::Info => self.validate_drawer_file(),
OperationType::Close => self.validate_close(),
OperationType::Key => self.validate_key_gen(),
}
}
fn validate_key_gen(&self) -> Result<(), DrawerError> {
self.validate_drawer_file()?;
let parent = match self.drawer_file.parent() {
None => Path::new("."),
Some(p) => {
if p == Path::new("") {
Path::new(".")
} else {
p
}
},
};
if !parent.exists() {
return Err(DrawerError::KeyOutputFailed(self.drawer_file.clone()));
}
Ok(())
}
fn key_path(&self) -> Result<PathBuf, DrawerError> {
match &self.key {
EnvVar => {
let val = std::env::var("DRAWER_KEY").map_err(|_| DrawerError::NoKeyPath)?;
Ok(PathBuf::from(val))
}
Path(p) => Ok(p.clone()),
}
}
fn validate_key(&self) -> Result<(), DrawerError> {
let key_path = self.key_path()?;
let file = std::fs::File::open(&key_path)
.map_err(|_| DrawerError::KeyInvalid(key_path.clone()))?;
let reader = std::io::BufReader::new(file);
let identity = age::ssh::Identity::from_buffer(reader, None)
.map_err(|_| DrawerError::KeyNotValidSsh)?;
age::ssh::Recipient::try_from(identity)
.map_err(|_| DrawerError::KeyNotValidSsh)?;
Ok(())
}
// Ensure the drawer file actually exists
fn validate_drawer_file(&self) -> Result<(), DrawerError> {
if !self.drawer_file.exists() {
return Err(DrawerError::DrawerFileNotFound(self.drawer_file.clone()));
}
Ok(())
}
fn perform_info(&self) -> Result<(), DrawerError> {
let encrypted = std::fs::read(&self.drawer_file)
.map_err(|_| DrawerError::DrawerFileNotFound(self.drawer_file.clone()))?;
let decrypted = self.decrypt(encrypted)?;
let info = archive_info(&decrypted)?;
match info {
ArchiveInfo::SingleFile { size } =>
println!("{} (file, {} bytes)", self.drawer_file.display(), size),
ArchiveInfo::Folder { file_count } =>
println!("{} (folder, {} files)", self.drawer_file.display(), file_count),
}
Ok(())
}
fn perform_key(&self) -> Result<(), DrawerError> {
let private_key = PrivateKey::random(&mut rand::rngs::OsRng, Algorithm::Ed25519)
.map_err(|_| DrawerError::KeyGenerateFailed)?;
let pem = private_key.to_openssh(LineEnding::LF)
.map_err(|_| DrawerError::KeyGenerateFailed)?;
std::fs::write(&self.drawer_file, pem.as_bytes())
.map_err(|_| DrawerError::KeyOutputFailed(self.drawer_file.clone()))
}
fn validate_close(&self) -> Result<(), DrawerError> {
let target = self.target_path.as_ref().cloned()
.unwrap_or_else(|| self.default_target(None));
if self.target_path.is_none() {
println!("(assuming from {})", target.display());
}
let meta = std::fs::metadata(&target)
.map_err(|_| DrawerError::TargetInvalid(target.clone()))?;
if !meta.is_dir() && !meta.is_file() {
return Err(DrawerError::TargetInvalid(target.clone()));
}
if meta.is_dir() && std::fs::read_dir(&target).is_err() {
return Err(DrawerError::TargetInvalid(target.clone()));
}
let canon_target = target.canonicalize()
.unwrap_or_else(|_| target.clone());
let drawer_parent = match self.drawer_file.parent() {
None => Path::new("."),
Some(p) if p == Path::new("") => {
Path::new(".")
},
Some(p) => p,
};
let canon_drawer = drawer_parent.canonicalize()
.unwrap_or_else(|_| drawer_parent.to_path_buf())
.join(self.drawer_file.file_name().unwrap_or_default());
if canon_drawer.starts_with(&canon_target) {
return Err(DrawerError::DrawerInsideTarget);
}
Ok(())
}
}