Struct SFrameHeader 

pub struct SFrameHeader {
    pub kid: u64,
    pub ctr: u64,
}

Decoded SFrame header fields.

Wire format (draft-ietf-sframe-enc §4.3):

┌─┬──────────┬──────────┬───────────────┬───────────────┐
│V│  K (3)   │  C (4)   │  KID  (var)   │  CTR  (var)   │
└─┴──────────┴──────────┴───────────────┴───────────────┘

• V (1 bit) — version, always 0 for SFrame v1.
• K (3 bits) — KID length in bytes minus one (0 → 1 byte, 7 → 8 bytes).
• C (4 bits) — CTR length in bytes minus one (0 → 1 byte, 15 → 16 bytes).
• KID — Key ID: (epoch << 16) | leaf_index.
• CTR — monotonic per-sender counter, big-endian.

Fields

kid: u64

Key ID: encodes both epoch and sender leaf index.

ctr: u64

Per-sender monotonic counter.

Implementations

impl SFrameHeader

pub fn kid_from(epoch: u64, leaf_index: u32) -> u64

Constructs the KID from an epoch and a leaf index.

Uses the lower 16 bits of leaf_index (supports up to 65 535 senders per epoch) and the full 48 available bits of epoch.

pub fn epoch_from_kid(kid: u64) -> u64

Extracts the epoch from a KID.

pub fn leaf_from_kid(kid: u64) -> u32

Extracts the leaf index from a KID.

pub fn encode(self) -> Vec<u8>

Encodes the header into bytes.

Layout: [flags_byte] [kid_bytes...] [ctr_bytes...] where flags_byte = 0 | ((kid_len-1) << 4) | (ctr_len-1).

pub fn decode(data: &[u8]) -> Result<(Self, usize), SFrameError>

Decodes a header from the front of data.

Returns the decoded header and the number of bytes consumed.

Trait Implementations

impl Clone for SFrameHeader

fn clone(&self) -> SFrameHeader

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Copy for SFrameHeader

impl Debug for SFrameHeader

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

Formats the value using the given formatter.

impl Eq for SFrameHeader

impl PartialEq for SFrameHeader

fn eq(&self, other: &SFrameHeader) -> 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 StructuralPartialEq for SFrameHeader