Crate tor_dirmgr

tor-dirmgr

Code to fetch, store, and update Tor directory information.

Overview

This crate is part of Arti, a project to implement Tor in Rust.

In its current design, Tor requires a set of up-to-date authenticated directory documents in order to build multi-hop anonymized circuits through the network.

This directory manager crate is responsible for figuring out which directory information we lack, downloading what we’re missing, and keeping a cache of it on disk.

Compile-time features

• mmap (default) – Use memory mapping to reduce the memory load for reading large directory objects from disk.

• routerdesc – (Incomplete) support for downloading and storing router descriptors.

• compression (default) – Build support for downloading compressed documents. Requires a C compiler.

• bridge-client: Provide APIs used to fetch and use bridge information.

• full – Enable all features above.

Non-additive features

• static – Try to link with a static copy of sqlite3.

Experimental and unstable features

Note that the APIs enabled by these features are NOT covered by semantic versioning¹ guarantees: we might break them or remove them between patch versions.

• experimental-api: Add additional non-stable APIs to our public interfaces.

• dirfilter: enable an experimental mechanism to modify incoming directory information before it is used.

• experimental: Enable all the above experimental features.

License: MIT OR Apache-2.0

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1. Remember, semantic versioning is what makes various cargo features work reliably. To be explicit: if you want cargo update to only make safe changes, then you cannot enable these features. ↩

Re-exports

pub use authority::Authority;

pub use authority::AuthorityBuilder;

pub use config::DirMgrConfig;

pub use config::DirTolerance;

pub use config::DirToleranceBuilder;

pub use config::DownloadScheduleConfig;

pub use config::DownloadScheduleConfigBuilder;

pub use config::NetworkConfig;

pub use config::NetworkConfigBuilder;

Modules

authority

Information about directory authorities

bootstrap 🔒

Functions to download or load directory objects, using the state machines in the states module.

bridgedescbridge-client

BridgeDescMgr - downloads and caches bridges’ router descriptors

config

Types for managing directory configuration.

docid 🔒

Declare a general purpose “document ID type” for tracking which documents we want and which we have.

docmeta 🔒

Types to describe information about other downloaded directory documents, without necessarily having the full document.

err 🔒

Declare an error type for the tor-dirmgr crate.

event 🔒

Code for notifying other modules about changes in the directory.

filterdirfilter

A filtering mechanism for directory objects.

retry 🔒

Configure timers for a timer for retrying a single failed fetch or object.

shared_ref 🔒

Utility module to safely refer to a mutable Arc.

state 🔒

Implementation for the primary directory state machine.

storage 🔒

Methods for storing and loading directory information from disk.

Structs

DirBootstrapEvents

A stream of DirBootstrapStatus events.

DirBootstrapStatus

Description of the directory manager’s current bootstrapping status.

DirMgr

A directory manager to download, fetch, and cache a Tor directory.

DirMgrStore

Storage manager used by DirMgr and BridgeDescMgr

DocumentText

A document returned by a directory manager.

DownloadSchedule

Configuration for how many times to retry a download, with what frequency.

DownloadScheduleBuilder

Builder for DownloadSchedule.

FallbackDir

A directory whose location ships with Tor (or arti), and which we can use for bootstrapping when we don’t know anything else about the network.

FallbackDirBuilder

Builder for FallbackDir.

SharedMutArcexperimental-api

A shareable mutable-ish optional reference to a an Arc.

Enums

DirBlockage

A reported diagnostic for what kind of trouble we’ve seen while trying to bootstrap a directory.

DocId

The identity of a single document, in enough detail to load it from storage.

DocSource

The possible origins of a document.

Error

An error originated by the directory manager code

Readiness 🔒

A degree of readiness for a given directory state object.

Timeliness

How “timely” must a network directory be?

Traits

DirProvider

Trait for DirMgr implementations

Functions

default_consensus_cutoff 🔒

Given a time now, and an amount of tolerated clock skew tolerance, return the age of the oldest consensus that we should request at that time.

supported_client_protocols

Return a list of the protocols supported by this crate when running as a client.

upgrade_weak_ref 🔒

Try to upgrade a weak reference to a DirMgr, and give an error on failure.

Type Aliases

Result

A Result as returned by this crate.