debian-packaging

debian-packaging is a library crate implementing functionality related to Debian packaging. The following functionality is (partially) implemented:

• Parsing and serializing control files
• Parsing Release and InRelease files.
• Parsing Packages files.
• Fetching Debian repository files from an HTTP server.
• Writing changelog files.
• Reading and writing .deb files.
• Creating repositories.
• PGP signing and verification operations.

See the crate's documentation for more.

lib.rs:

Debian packaging primitives.

This crate defines pure Rust implementations of Debian packaging primitives. Debian packaging (frequently interacted with by tools like apt and apt-get) provides the basis for packaging on Debian-flavored Linux distributions like Debian and Ubuntu.

Goals

Compliance and Compatibility

We want this crate to be as-compliant and as-compatible as possible with in-the-wild Debian packaging deployments so it can be used as a basis to implementing tools which consume and produce entities that are compatible with the official Debian packaging implementations.

This crate could be considered an attempt to reimplement aspects of apt in pure Rust. (The apt repository defines command line tools like apt-get as well as libraries like libapt-pkg and libapt-inst. This crate is more focused on providing the library-level interfaces. However, a goal is to have as much code be usable as a library so the surface area of any tools is minimal.)

Determinism and Reproducibility

To help combat the rise in software supply chain attacks and to make debugging and testing easier, a goal of this crate is to be as deterministic and reproducible as possible.

Given the same source code / version of this crate, operations like creating a .deb file or building a repository from indexed .deb files should be as byte-for-byte identical as reasonably achievable.

Performance

We strive for highly optimal implementations of packaging primitives wherever possible.

We want to facilitate intensive operations (like reading all packages in a Debian repository) or publishing to a repository to scale out to as many CPU cores as possible.

Read operations like parsing control files or version strings should be able to use 0-copy to avoid excessive memory allocations and copying.

A Tour of Functionality

A .deb file defines a Debian package. Readers and writers of .deb files exist in the [deb] module. To read the contents of a .deb defining a binary package, use deb::reader::BinaryPackageReader. To create new .deb files, use deb::builder::DebBuilder.

A common primitive within Debian packaging is control files. These consist of paragraphs of key-value metadata. Low-level control file primitives are defined in the [control] module. control::ControlParagraph defines a paragraph, which consists of control::ControlField. control::ControlFile provides an interface for a control file, which consists of multiple paragraphs. control::ControlParagraphReader implements a streaming reader of control files and control::ControlParagraphAsyncReader implements an asynchronous streaming reader.

There are different flavors of control files within Debian packaging. binary_package_control::BinaryPackageControlFile defines a control file for a binary package. This type provides helper functions for resolving common fields on binary control files. debian_source_control::DebianSourceControlFile defines a control file for a source package, as expressed in a .dsc file.

There is a meta language for expressing dependencies between Debian packages. The [dependency] module defines types for parsing and writing this language. e.g. dependency::DependencyList represents a parsed list of dependencies like libc6 (>= 2.4), libx11-6. dependency::PackageDependencyFields represents a collection of control fields that define relationships between packages.

The [package_version] module implements Debian package version string parsing, serialization, and comparison. package_version::PackageVersion is the main type used for this.

The [dependency_resolution] module implements functionality related to resolving dependencies. e.g. dependency_resolution::DependencyResolver can be used to index known binary packages and find direct and transitive dependencies. This could be used as the basis for a package manager or other tool wishing to walk the dependency tree for a given package.

The [repository] module provides functionality related to Debian repositories, which are publications of Debian packages and metadata. The repository::RepositoryRootReader trait provides an interface for reading the root directory of a repository and repository::ReleaseReader provides an interface for reading content from a parsed [In]Release file. The repository::RepositoryWriter trait abstracts I/O for writing to a repository. Repository interaction involves many support primitives. repository::release::ReleaseFile represents an [In]Release file. Support for verifying PGP signatures is provided. repository::contents::ContentsFile represents a Contents file.

Concrete implementations of repository interaction exist. repository::http::HttpRepositoryClient enables reading from an HTTP-hosted repository (e.g. http://archive.canonical.com/ubuntu). repository::filesystem::FilesystemRepositoryWriter enables writing repositories to a local filesystem.

The repository::builder module contains functionality for creating and publishing Debian repositories. repository::builder::RepositoryBuilder is the main type for publishing Debian repositories.

The repository::copier module contains functionality for copying Debian repositories. repository::copier::RepositoryCopier is the main type for copying Debian repositories.

The [signing_key] module provides functionality related to PGP signing. signing_key::DistroSigningKey defines PGP public keys for well-known signing keys used by popular Linux distributions. [signing_key::signing_secret_key_params_builder()] and [signing_key::create_self_signed_key()] enable easily creating signing keys for Debian repositories.

Various other modules provide miscellaneous functionality. [io] defines I/O helpers, including stream adapters for validating content digests on read and computing content digests on write.

Crate Features

The optional and enabled-by-default http feature enables HTTP client support for interacting with Debian repositories via HTTP.