Crate roughenough

An implementation of the Roughtime secure time synchronization protocol.

Roughtime aims to achieve rough time synchronisation in a secure way that doesn’t depend on any particular time server, and in such a way that, if a time server does misbehave, clients end up with cryptographic proof of it.

Protocol

Roughtime messages are represented by RtMessage which implements the mapping of Roughtime u32 tags to byte-strings.

Keys and Signing

Roughtime uses an Ed25519 key pair as the server’s long-term identity and a second key pair (signed by the long-term key) as a delegated on-line (ephemeral) key.

LongTermKey and OnlineKey implement these elements of the protocol. The sign module provides signing and verification operations.

Client

A Roughtime client can be found in src/bin/client.rs. To run the client:

$ cargo run --release --bin client roughtime.int08h.com 2002

Consult the client’s --help output for all runtime options.

Server

The core Roughtime server implementation is in src/server.rs and the server’s CLI can be found in src/bin/roughenough-server.rs.

The server has multiple ways it can be configured, see ServerConfig for the configuration trait and

Modules

config

Ways to configure the Roughenough server.

grease

Adds deliberate errors to client responses as part of the Roughtime Ecosystem.

key

Representations and management of Roughtime’s online and long-term Ed25519 keys

kms

Protect the server’s long-term key with envelope encryption and a key management system.

merkle

Merkle Tree implementation using SHA-512 and the Roughtime leaf and node tweak values.

server

Implements the Roughenough server functionality.

sign

A multi-step (init-update-finish) interface for Ed25519 signing and verification

stats

Facilities for tracking client requests to the server

Structs

RtMessage

A Roughtime protocol message; a map of u32 tags to arbitrary byte-strings.

Enums

Error

Error types generated by this implementation

Tag

An unsigned 32-bit value (key) that maps to a byte-string (value).

Constants

CERTIFICATE_CONTEXT

Prefixed to the server’s certificate before generating or verifying certificate’s signature

HASH_LENGTH

Size (in bytes) of a SHA-512 hash

MIN_REQUEST_LENGTH

Minimum size (in bytes) of a client request

NONCE_LENGTH

Size (in bytes) of the client’s nonce

PUBKEY_LENGTH

Size (in bytes) of an Ed25519 public key

RADIUS_LENGTH

Size (in bytes) of server’s time uncertainty value

SEED_LENGTH

Size (in bytes) of seeds used to derive private keys

SIGNATURE_LENGTH

Size (in bytes) of an Ed25519 signature

SIGNED_RESPONSE_CONTEXT

Prefixed to the server’s response before generating or verifying the server’s signature

TIMESTAMP_LENGTH

Size (in bytes) of server’s timestamp value

TREE_LEAF_TWEAK

Value prepended to leaves prior to hashing

TREE_NODE_TWEAK

Value prepended to nodes prior to hashing

VERSION

Version of Roughenough

Functions

roughenough_version

Roughenough version string enriched with any compile-time optional features