#![allow(clippy::derive_partial_eq_without_eq)]
// https://github.com/hyperium/tonic/issues/1056
use std::collections::HashSet;
use thiserror::Error;
use prost::Message;
use crate::store_path::{ParseStorePathError, StorePath};
tonic::include_proto!("tvix.store.v1");
#[cfg(feature = "reflection")]
/// Compiled file descriptors for implementing [gRPC
/// reflection](https://github.com/grpc/grpc/blob/master/doc/server-reflection.md) with e.g.
/// [`tonic_reflection`](https://docs.rs/tonic-reflection).
pub const FILE_DESCRIPTOR_SET: &[u8] = tonic::include_file_descriptor_set!("tvix.store.v1");
/// Errors that can occur during the validation of Directory messages.
#[derive(Debug, PartialEq, Eq, Error)]
pub enum ValidateDirectoryError {
/// Elements are not in sorted order
#[error("{0} is not sorted")]
WrongSorting(String),
/// Multiple elements with the same name encountered
#[error("{0} is a duplicate name")]
DuplicateName(String),
/// Invalid name encountered
#[error("Invalid name in {0}")]
InvalidName(String),
/// Invalid digest length encountered
#[error("Invalid Digest length: {0}")]
InvalidDigestLen(usize),
}
/// Errors that can occur during the validation of PathInfo messages.
#[derive(Debug, Error, PartialEq)]
pub enum ValidatePathInfoError {
/// No node present
#[error("No node present")]
NoNodePresent(),
/// Invalid node name encountered.
#[error("Failed to parse {0} as NixPath: {1}")]
InvalidNodeName(String, ParseStorePathError),
/// The digest the (root) node refers to has invalid length.
#[error("Invalid Digest length: {0}")]
InvalidDigestLen(usize),
/// The number of references in the narinfo.reference_names field does not match
/// the number of references in the .references field.
#[error("Inconsistent Number of References: {0} (references) vs {0} (narinfo)")]
InconsistentNumberOfReferences(usize, usize),
}
/// Checks a Node name for validity as an intermediate node, and returns an
/// error that's generated from the supplied constructor.
///
/// We disallow slashes, null bytes, '.', '..' and the empty string.
fn validate_node_name<E>(name: &str, err: fn(String) -> E) -> Result<(), E> {
if name.is_empty() || name == ".." || name == "." || name.contains('\x00') || name.contains('/')
{
return Err(err(name.to_string()));
}
Ok(())
}
/// Checks a digest for validity.
/// Digests are 32 bytes long, as we store blake3 digests.
fn validate_digest<E>(digest: &Vec<u8>, err: fn(usize) -> E) -> Result<(), E> {
if digest.len() != 32 {
return Err(err(digest.len()));
}
Ok(())
}
/// Parses a root node name.
///
/// On success, this returns the parsed [StorePath].
/// On error, it returns an error generated from the supplied constructor.
fn parse_node_name_root<E>(
name: &str,
err: fn(String, ParseStorePathError) -> E,
) -> Result<StorePath, E> {
match StorePath::from_string(name) {
Ok(np) => Ok(np),
Err(e) => Err(err(name.to_string(), e)),
}
}
impl PathInfo {
/// validate performs some checks on the PathInfo struct,
/// Returning either a [StorePath] of the root node, or a
/// [ValidatePathInfoError].
pub fn validate(&self) -> Result<StorePath, ValidatePathInfoError> {
// If there is a narinfo field populated, ensure the number of references there
// matches PathInfo.references count.
if let Some(narinfo) = &self.narinfo {
if narinfo.reference_names.len() != self.references.len() {
return Err(ValidatePathInfoError::InconsistentNumberOfReferences(
narinfo.reference_names.len(),
self.references.len(),
));
}
}
// FUTUREWORK: parse references in reference_names. ensure they start
// with storeDir, and use the same digest as in self.references.
// Ensure there is a (root) node present, and it properly parses to a [StorePath].
let root_nix_path = match &self.node {
None => {
return Err(ValidatePathInfoError::NoNodePresent());
}
Some(Node { node }) => match node {
None => {
return Err(ValidatePathInfoError::NoNodePresent());
}
Some(node::Node::Directory(directory_node)) => {
// ensure the digest has the appropriate size.
validate_digest(
&directory_node.digest,
ValidatePathInfoError::InvalidDigestLen,
)?;
// parse the name
parse_node_name_root(
&directory_node.name,
ValidatePathInfoError::InvalidNodeName,
)?
}
Some(node::Node::File(file_node)) => {
// ensure the digest has the appropriate size.
validate_digest(&file_node.digest, ValidatePathInfoError::InvalidDigestLen)?;
// parse the name
parse_node_name_root(&file_node.name, ValidatePathInfoError::InvalidNodeName)?
}
Some(node::Node::Symlink(symlink_node)) => {
// parse the name
parse_node_name_root(
&symlink_node.name,
ValidatePathInfoError::InvalidNodeName,
)?
}
},
};
// return the root nix path
Ok(root_nix_path)
}
}
/// NamedNode is implemented for [FileNode], [DirectoryNode] and [SymlinkNode],
/// so we can ask all three for their name easily.
trait NamedNode {
fn get_name(&self) -> &str;
}
impl NamedNode for &FileNode {
fn get_name(&self) -> &str {
self.name.as_str()
}
}
impl NamedNode for &DirectoryNode {
fn get_name(&self) -> &str {
self.name.as_str()
}
}
impl NamedNode for &SymlinkNode {
fn get_name(&self) -> &str {
self.name.as_str()
}
}
/// Accepts a name, and a mutable reference to the previous name.
/// If the passed name is larger than the previous one, the reference is updated.
/// If it's not, an error is returned.
fn update_if_lt_prev<'set, 'n>(
prev_name: &'set mut &'n str,
name: &'n str,
) -> Result<(), ValidateDirectoryError> {
if *name < **prev_name {
return Err(ValidateDirectoryError::WrongSorting(name.to_string()));
}
*prev_name = name;
Ok(())
}
/// Inserts the given name into a HashSet if it's not already in there.
/// If it is, an error is returned.
fn insert_once<'n>(
seen_names: &mut HashSet<&'n str>,
name: &'n str,
) -> Result<(), ValidateDirectoryError> {
if seen_names.get(name).is_some() {
return Err(ValidateDirectoryError::DuplicateName(name.to_string()));
}
seen_names.insert(name);
Ok(())
}
impl Directory {
/// The size of a directory is the number of all regular and symlink elements,
/// the number of directory elements, and their size fields.
pub fn size(&self) -> u32 {
self.files.len() as u32
+ self.symlinks.len() as u32
+ self
.directories
.iter()
.fold(0, |acc: u32, e| (acc + 1 + e.size) as u32)
}
/// Calculates the digest of a Directory, which is the blake3 hash of a
/// Directory protobuf message, serialized in protobuf canonical form.
pub fn digest(&self) -> Vec<u8> {
let mut hasher = blake3::Hasher::new();
hasher.update(&self.encode_to_vec()).finalize().as_bytes()[..].to_vec()
}
/// validate checks the directory for invalid data, such as:
/// - violations of name restrictions
/// - invalid digest lengths
/// - not properly sorted lists
/// - duplicate names in the three lists
pub fn validate(&self) -> Result<(), ValidateDirectoryError> {
let mut seen_names: HashSet<&str> = HashSet::new();
let mut last_directory_name: &str = "";
let mut last_file_name: &str = "";
let mut last_symlink_name: &str = "";
// check directories
for directory_node in &self.directories {
validate_node_name(&directory_node.name, ValidateDirectoryError::InvalidName)?;
validate_digest(
&directory_node.digest,
ValidateDirectoryError::InvalidDigestLen,
)?;
update_if_lt_prev(&mut last_directory_name, directory_node.name.as_str())?;
insert_once(&mut seen_names, directory_node.name.as_str())?;
}
// check files
for file_node in &self.files {
validate_node_name(&file_node.name, ValidateDirectoryError::InvalidName)?;
validate_digest(&file_node.digest, ValidateDirectoryError::InvalidDigestLen)?;
update_if_lt_prev(&mut last_file_name, file_node.name.as_str())?;
insert_once(&mut seen_names, file_node.name.as_str())?;
}
// check symlinks
for symlink_node in &self.symlinks {
validate_node_name(&symlink_node.name, ValidateDirectoryError::InvalidName)?;
update_if_lt_prev(&mut last_symlink_name, symlink_node.name.as_str())?;
insert_once(&mut seen_names, symlink_node.name.as_str())?;
}
Ok(())
}
}
