#![allow(clippy::derive_partial_eq_without_eq)] // https://github.com/hyperium/tonic/issues/1056 use std::{collections::HashSet, iter::Peekable}; use thiserror::Error; use prost::Message; use nix_compat::store_path::{ParseStorePathError, StorePath}; mod grpc_blobservice_wrapper; mod grpc_directoryservice_wrapper; pub use grpc_blobservice_wrapper::GRPCBlobServiceWrapper; pub use grpc_directoryservice_wrapper::GRPCDirectoryServiceWrapper; 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"); #[cfg(test)] mod tests; /// 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] /// and [node::Node], so we can ask all of them for the name easily. pub 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() } } impl NamedNode for node::Node { fn get_name(&self) -> &str { match self { node::Node::File(node_file) => &node_file.name, node::Node::Directory(node_directory) => &node_directory.name, node::Node::Symlink(node_symlink) => &node_symlink.name, } } } /// 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)) } /// 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(()) } /// Allows iterating over all three nodes ([DirectoryNode], [FileNode], /// [SymlinkNode]) in an ordered fashion, as long as the individual lists /// are sorted (which can be checked by the [Directory::validate]). pub fn nodes(&self) -> DirectoryNodesIterator { return DirectoryNodesIterator { i_directories: self.directories.iter().peekable(), i_files: self.files.iter().peekable(), i_symlinks: self.symlinks.iter().peekable(), }; } } /// Struct to hold the state of an iterator over all nodes of a Directory. /// /// Internally, this keeps peekable Iterators over all three lists of a /// Directory message. pub struct DirectoryNodesIterator<'a> { // directory: &Directory, i_directories: Peekable<std::slice::Iter<'a, DirectoryNode>>, i_files: Peekable<std::slice::Iter<'a, FileNode>>, i_symlinks: Peekable<std::slice::Iter<'a, SymlinkNode>>, } /// looks at two elements implementing NamedNode, and returns true if "left /// is smaller / comes first". /// /// Some(_) is preferred over None. fn left_name_lt_right<A: NamedNode, B: NamedNode>(left: Option<&A>, right: Option<&B>) -> bool { match left { // if left is None, right always wins None => false, Some(left_inner) => { // left is Some. match right { // left is Some, right is None - left wins. None => true, Some(right_inner) => { // both are Some - compare the name. return left_inner.get_name() < right_inner.get_name(); } } } } } impl Iterator for DirectoryNodesIterator<'_> { type Item = node::Node; // next returns the next node in the Directory. // we peek at all three internal iterators, and pick the one with the // smallest name, to ensure lexicographical ordering. // The individual lists are already known to be sorted. fn next(&mut self) -> Option<Self::Item> { if left_name_lt_right(self.i_directories.peek(), self.i_files.peek()) { // i_directories is still in the game, compare with symlinks if left_name_lt_right(self.i_directories.peek(), self.i_symlinks.peek()) { self.i_directories .next() .cloned() .map(node::Node::Directory) } else { self.i_symlinks.next().cloned().map(node::Node::Symlink) } } else { // i_files is still in the game, compare with symlinks if left_name_lt_right(self.i_files.peek(), self.i_symlinks.peek()) { self.i_files.next().cloned().map(node::Node::File) } else { self.i_symlinks.next().cloned().map(node::Node::Symlink) } } } }