Struct HsDirParams

pub struct HsDirParams {
    pub(crate) time_period: TimePeriod,
    pub(crate) shared_rand: SharedRandVal,
    pub(crate) srv_lifespan: Range<SystemTime>,
}

Available on crate feature hs-common only.

Parameters for generating and using an HsDir ring.

These parameters are derived from the shared random values and time parameters in the consensus, and are used to determine the position of each HsDir within the ring.

Fields

time_period: TimePeriod

The time period for this ring. It’s used to ensure that blinded onion keys rotate in a predictable way over time.

shared_rand: SharedRandVal

The SharedRandVal for this ring. It’s used to ensure that the position of each HsDir within the ring rotates unpredictably over time.

srv_lifespan: Range<SystemTime>

The range of times over which the srv is most current.

Implementations

impl HsDirParams

pub fn time_period(&self) -> TimePeriod

Return the time period for which these parameters are valid.

The hs_blind_id for an onion service changes every time period: when uploading, callers should use this time period to determine which hs_blind_id’s descriptor should be sent to which directory.

pub fn start_of_shard_rand_period(&self) -> SystemTime

Return the starting time for the shared-random-value protocol that produced the SRV for this time period.

pub fn offset_within_srv_period( &self, when: SystemTime, ) -> Option<SrvPeriodOffset>

Available on crate feature hs-service only.

Return an opaque offset for when from the start of the shared-random-value protocol period corresponding to the SRV for this time period.

When uploading, callers should this offset to determine the revision counter for their descriptors.

Returns None if when is after the start of the SRV period.

pub(crate) fn compute( consensus: &MdConsensus, params: &NetParameters, ) -> Result<HsDirs<HsDirParams>>

Compute the HsDirParams for the current time period, according to a given consensus.

rend-spec-v3 section 2.2.1 et seq

Return the ring parameters for the current period (which clients use when fetching onion service descriptors), along with a Vec of ring parameters for any secondary periods that onion services should additionally use when publishing their descriptors.

Note that “current” here is always relative to a given consensus, not the current wall-clock time.

(This function’s return type is a bit cumbersome; these parameters are bundled together because it is efficient to compute them all at once.)

Note that this function will only return an error if something is extremely wrong with the provided consensus: for other error cases, it returns a “disaster fallback”.

Trait Implementations

impl Clone for HsDirParams

fn clone(&self) -> HsDirParams

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for HsDirParams

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

Formats the value using the given formatter.

impl PartialEq for HsDirParams

fn eq(&self, other: &HsDirParams) -> bool

Tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Rhs) -> bool

Tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl Eq for HsDirParams

impl StructuralPartialEq for HsDirParams