Struct AttestationData 

pub struct AttestationData {
    pub slot: u64,
    pub index: u64,
    pub beacon_block_root: Bytes32,
    pub source: Checkpoint,
    pub target: Checkpoint,
}

Attester vote payload.

Per SPEC §3.3. Field layout is frozen as wire protocol — see AttestationData::signing_root for the exact byte order used by BLS signing.

Fields

slot: u64

L2 slot the attestation targets.

index: u64

Committee index within the slot.

beacon_block_root: Bytes32

Head vote: canonical beacon block root at slot.

source: Checkpoint

FFG source checkpoint.

target: Checkpoint

FFG target checkpoint.

Implementations

impl AttestationData

pub fn signing_root(&self, network_id: &Bytes32) -> Bytes32

Compute the BLS signing root for this attestation.

Implements DSL-004. Traces to SPEC §3.3.

Wire layout

The hasher is fed the following bytes, in order:

DOMAIN_BEACON_ATTESTER    (22 bytes, "DIG_BEACON_ATTESTER_V1")
network_id                (32 bytes)
slot                      (8 bytes, little-endian u64)
index                     (8 bytes, little-endian u64)
beacon_block_root         (32 bytes)
source.epoch              (8 bytes, little-endian u64)
source.root               (32 bytes)
target.epoch              (8 bytes, little-endian u64)
target.root               (32 bytes)

Total input: 182 bytes. Output: 32-byte SHA-256 digest.

Invariants

• Deterministic: identical (self, network_id) inputs always produce bit-identical output.
• Domain-bound: prefixed with DOMAIN_BEACON_ATTESTER; the tag is NOT a separate field of the struct.
• Network-bound: network_id mixed in after the tag; a signing root produced for testnet does NOT verify under mainnet.
• Field-covering: every field (including both Checkpoint components) contributes to the digest; mutating any one shifts the output.

All four invariants are enforced by tests/dsl_004_attestation_data_signing_root_test.rs.

Endianness

All integer fields (slot, index, source.epoch, target.epoch) use little-endian encoding via u64::to_le_bytes. Little-endian is the wire-level standard for DIG / Chia; the test suite guards against accidental big-endian drift.

No custom hashing

Uses chia_sha2::Sha256 directly — do NOT introduce a generic sha2 crate dep for this codebase (SPEC §5 hard rule, dt-hard-rules Rule 4).

Trait Implementations

impl Clone for AttestationData

fn clone(&self) -> AttestationData

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for AttestationData

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

Formats the value using the given formatter.

impl<'de> Deserialize<'de> for AttestationData

fn deserialize<__D>(__deserializer: __D) -> Result<Self, __D::Error>

where __D: Deserializer<'de>,

Deserialize this value from the given Serde deserializer.

impl Hash for AttestationData

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl PartialEq for AttestationData

fn eq(&self, other: &AttestationData) -> 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 Serialize for AttestationData

fn serialize<__S>(&self, __serializer: __S) -> Result<__S::Ok, __S::Error>

where __S: Serializer,

Serialize this value into the given Serde serializer.

impl Eq for AttestationData

impl StructuralPartialEq for AttestationData