Struct NsAvidmGf2Scheme 

pub struct NsAvidmGf2Scheme;

Dummy struct for namespaced AvidmGf2 scheme

Implementations

impl NsAvidmGf2Scheme

pub fn setup( recovery_threshold: usize, total_weights: usize, ) -> Result<NsAvidmGf2Param, VidError>

Setup an instance for AVID-M scheme

pub fn commit( param: &NsAvidmGf2Param, payload: &[u8], ns_table: impl IntoIterator<Item = Range<usize>>, ) -> Result<(NsAvidmGf2Commit, NsAvidmGf2Common), VidError>

Commit to a payload given namespace table. WARN: it assumes that the namespace table is well formed, i.e. ranges are non-overlapping and cover the whole payload.

pub fn aggregate_commit( ns_commits: &[AvidmGf2Commit], ) -> Result<NsAvidmGf2Commit, VidError>

Aggregate per-namespace commitments into the top-level namespaced commitment (the Merkle root over the namespace commits).

Lets a caller that has already computed each namespace’s commit (e.g. via Self::ns_disperse_one) form the block commitment without re-encoding.

pub fn is_consistent( commit: &NsAvidmGf2Commit, common: &NsAvidmGf2Common, ) -> bool

Check whether the namespaced commitment is consistent with the common data

pub fn ns_disperse( param: &NsAvidmGf2Param, distribution: &[u32], payload: &[u8], ns_table: impl IntoIterator<Item = Range<usize>>, ) -> Result<(NsAvidmGf2Commit, NsAvidmGf2Common, Vec<NsAvidmGf2Share>), VidError>

Disperse a payload according to a distribution table and a namespace table. WARN: it assumes that the namespace table is well formed, i.e. ranges are non-overlapping and cover the whole payload.

pub fn ns_disperse_one( param: &NsAvidmGf2Param, distribution: &[u32], ns_payload: &[u8], ns_index: usize, ) -> Result<NsDispersal, VidError>

Disperse a single namespace’s slice of the payload.

ns_payload is the namespace’s bytes and ns_index its position in the namespace table.

pub fn verify_share_with_verified_common( common: &NsAvidmGf2Common, share: &NsAvidmGf2Share, ) -> Result<Result<(), ()>, VidError>

Verify a namespaced share given already-verified common data.

Besides each namespace’s Merkle proofs, this checks that each namespace’s shards have the size its ns_lens entry disperses to. The commitment binds ns_commits but not ns_lens, so without this a share could declare any payload length and have it believed. With it, each declared length is pinned to within 2 * recovery_threshold bytes of the one the shards were built from.

That window is per namespace, and the disperser chooses how many namespaces there are, so the misdeclared total adds up: a payload split into namespaces shorter than a window can declare each as a single byte and still verify. This rejects gross forgeries early, such as a shrunken one-namespace block or an absurd length; it does not bound the total. Exact binding needs a verifier that knows the payload’s namespace table, or a commitment that covers ns_lens.

Safety Contract

Caller MUST ensure is_consistent(commit, common) returned true before calling this. Without that check, a malicious common could make an invalid share appear valid.

pub fn verify_share( commit: &NsAvidmGf2Commit, common: &NsAvidmGf2Common, share: &NsAvidmGf2Share, ) -> Result<Result<(), ()>, VidError>

Verify a namespaced share

pub fn recover( common: &NsAvidmGf2Common, shares: &[NsAvidmGf2Share], ) -> Result<Vec<u8>, VidError>

Recover the entire payload from enough share

pub fn ns_recover( common: &NsAvidmGf2Common, ns_index: usize, shares: &[NsAvidmGf2Share], ) -> Result<Vec<u8>, VidError>

Recover the payload for a given namespace. Given namespace ID should be valid for all shares, i.e. ns_commits and content have at least ns_index elements for all shares.

fn ns_len_matches_shards( param: &NsAvidmGf2Param, ns_len: usize, content: &AvidmGf2Share, ) -> bool

Whether content’s shards have the size an ns_len-byte namespace disperses to under param.

impl NsAvidmGf2Scheme

pub fn namespace_proof( common: &NsAvidmGf2Common, payload: &[u8], ns_index: usize, ) -> Result<NsProof, VidError>

Generate a proof of inclusion for a namespace payload.

pub fn verify_namespace_proof( commit: &NsAvidmGf2Commit, common: &NsAvidmGf2Common, proof: &NsProof, ) -> Result<Result<(), ()>, VidError>

Verify a namespace proof against a namespaced VID commitment.