Module protocol 

FIPS Protocol Messages

Wire format definitions for FIPS protocol communication across two layers:

Link Layer (peer-to-peer, hop-by-hop)

Messages exchanged between directly connected peers over Noise-encrypted links. Includes spanning tree gossip, bloom filter propagation, discovery protocol, and forwarding of session-layer datagrams.

Link-layer peer authentication uses Noise IK (see noise.rs), which establishes the encrypted channel before any of these messages are sent.

Session Layer (end-to-end, between FIPS addresses)

Messages exchanged between source and destination FIPS nodes, encrypted with session keys that intermediate nodes cannot read. Includes session establishment, IPv6 datagram encapsulation, and routing errors.

Session-layer datagrams are carried as opaque payloads through the link layer, encrypted end-to-end independently of per-hop link encryption.

Structs

CoordsRequired

Link-layer error signal indicating router cache miss.

Disconnect

Orderly disconnect notification sent before closing a peer link.

FilterAnnounce

Bloom filter announcement for reachability propagation.

FspFlags

FSP common prefix flags (cleartext, in outer header).

FspInnerFlags

FSP inner header flags (encrypted, inside AEAD envelope).

LookupRequest

Request to discover a node’s coordinates.

LookupResponse

Response to a lookup request with target’s coordinates.

MtuExceeded

Error indicating a forwarded packet exceeded the next-hop transport MTU.

PathBroken

Error indicating routing failure (local minimum or unreachable).

PathMtuNotification

Path MTU notification (msg_type 0x13).

SessionAck

Session acknowledgement.

SessionDatagram

Encapsulated session-layer datagram for multi-hop forwarding.

SessionDatagramRef

Zero-copy view over a SessionDatagram. The inner payload is a borrowed slice into the caller’s buffer — no allocation, no memcpy.

SessionFlags

Session flags for setup options.

SessionMsg3

XK handshake message 3 (initiator -> responder).

SessionReceiverReport

Session-layer receiver report (msg_type 0x12).

SessionSenderReport

Session-layer sender report (msg_type 0x11).

SessionSetup

Session setup to establish cached coordinate state.

TreeAnnounce

Spanning tree announcement carrying parent declaration and ancestry.

Enums

DisconnectReason

Reason for an orderly disconnect notification.

HandshakeMessageType

Handshake message type identifiers.

LinkMessageType

Link-layer message type identifiers.

ProtocolError

Errors related to protocol message handling.

SessionMessageType

SessionDatagram payload message type identifiers.

Constants

COORDS_REQUIRED_SIZE

Wire size of CoordsRequired payload: msg_type(1) + flags(1) + dest_addr(16) + reporter(16).

MTU_EXCEEDED_SIZE

Wire size of MtuExceeded payload: msg_type(1) + flags(1) + dest_addr(16) + reporter(16) + mtu(2).

PATH_MTU_NOTIFICATION_SIZE

Body size for PathMtuNotification.

PROTOCOL_VERSION

Protocol version for message compatibility.

SESSION_DATAGRAM_HEADER_SIZE

SessionDatagram fixed header size: msg_type(1) + ttl(1) + path_mtu(2) + src_addr(16) + dest_addr(16).

SESSION_RECEIVER_REPORT_SIZE

Body size for SessionReceiverReport: 2 reserved + 64 fields.

SESSION_SENDER_REPORT_SIZE

Body size for SessionSenderReport: 2 reserved + 44 fields.

Type Aliases

MessageTypeDeprecated