Struct MachineIdFile 

pub struct MachineIdFile { /* private fields */ }

/etc/machine-id — the systemd-managed primary host identifier on modern Linux.

Known-duplicate filtering

A non-trivial fraction of Linux installs ship or end up with machine-id values that are identical across many machines (Whonix’s deliberate anti-fingerprinting constant; official container images that bake a single hex value into the filesystem layer; synthetic all-same-nibble values from broken image builds). Returning one of those would produce a silently non-unique identity shared by every host that inherits it, so this source additionally rejects, by returning Ok(None) with a log::debug! entry:

• A curated list of public, citable shared values (MACHINE_ID_DENYLIST).
• Any 32-hex-digit value whose nibbles are all the same character (00…0, 11…1, aa…a, etc.). The systemd spec forbids all-zero machine-ids outright; the rest are only ever seen on synthetic or corrupt images.

Anything not matching the filter passes through unchanged — the intent is to reject known garbage, not to gate on machine-id shape. A false positive here drops a legitimate host from identity resolution, so a missing entry is strictly preferable to an over-broad rule.

Implementations

impl MachineIdFile

pub fn new() -> Self

Read from the standard path (/etc/machine-id).

pub fn at(path: impl Into<PathBuf>) -> Self

Read from a caller-supplied path. Useful for tests and unusual image layouts.

pub fn path(&self) -> &Path

The configured path.

Trait Implementations

impl Clone for MachineIdFile

fn clone(&self) -> MachineIdFile

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for MachineIdFile

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Default for MachineIdFile

fn default() -> Self

Returns the “default value” for a type.

impl Source for MachineIdFile

fn kind(&self) -> SourceKind

Provenance label for this source. Shown in error messages and the resolved crate::HostId.

fn probe(&self) -> Result<Option<Probe>, Error>

Attempt to produce a raw identifier.