Crate osdp 

Pure-Rust, no_std-friendly implementation of the SIA OSDP v2.2 protocol.

Crate features

• std (default): enables alloc, plus desktop convenience.
• alloc (default via std): enables alloc::vec::Vec-based codec paths.
• secure-channel (default): enables Annex D (AES-128, MAC, encryption).
• embedded-io / embedded-io-async: transport adapters.
• defmt: structured logging on embedded targets.

Layering

See architecture for a rendered diagram of how these modules relate.

• packet — wire framing (SOM, header, SCB, MAC, trailer)
• command / reply — typed messages
• multipart — RFC §5.10 multi-part assembly / disassembly
• secure — Annex D secure channel
• transport — byte-stream abstraction
• driver — ACU and PD state machines
• caps — Annex B function codes

Quick start

Drive a PD at address 0x05 through one POLL exchange. The example uses transport::VecTransport, so without a peer feeding bytes back the exchange will end in driver::acu::ExchangeOutcome::Timeout — wire it up to a real Transport (or another VecTransport, see examples/loopback_poll.rs) for a successful round-trip.

use osdp::clock::SystemClock;
use osdp::command::{Command, Poll};
use osdp::driver::acu::{Acu, ExchangeOutcome, PdState};
use osdp::reply::Reply;
use osdp::transport::VecTransport;

let mut acu = Acu::new(VecTransport::new(), SystemClock::new());
let mut pd = PdState::default();
match acu.exchange(0x05, &mut pd, &Command::Poll(Poll))? {
    ExchangeOutcome::Reply(Reply::Ack(_)) => { /* PD alive */ }
    ExchangeOutcome::Busy => { /* PD asked us to back off */ }
    ExchangeOutcome::Timeout => { /* no reply within budget */ }
    ExchangeOutcome::Offline => { /* PD declared offline */ }
    _ => {}
}

For the secure-channel walk see examples/handshake.rs; for an end-to-end loopback that exercises SQN cycling see examples/loopback_poll.rs.

Specification cross-references

All spec citations refer to SIA OSDP v2.2 (©2020 Security Industry Association). Where an item maps directly onto a spec section it is noted in the docs as # Spec: §X.Y.

Re-exports

pub use error::Error;

pub use error::Result;

pub use packet::Address;

pub use packet::ControlByte;

pub use packet::ParsedPacket;

pub use packet::Sqn;

pub use packet::Trailer;

pub use packet::Packet;alloc

Modules

architecture

Crate architecture diagram.

caps

PD capability function codes.

clock

Time abstraction. Drivers take a Clock so that timing logic is testable from no_std targets without pulling in a runtime.

commandalloc

Typed OSDP commands (ACU → PD).

driveralloc

Higher-level drivers built atop the codec and transport.

error

Crate-wide error type. core::error::Error-compatible.

multipartalloc

Multi-part message engine.

packet

Packet codec — framing, header, security control block, MAC, trailer.

replyalloc

Typed OSDP replies (PD → ACU). See sibling crate::command.

securealloc and secure-channel

Secure Channel — Annex D.

transport

Transport abstraction. The driver works against any half-duplex byte stream that exposes Transport::write_all and Transport::read.

Constants

BROADCAST_ADDR

Broadcast address.

MAX_BUS_PACKET

Maximum packet length that any device must tolerate on the wire (even if addressed elsewhere).

MAX_PD_ADDR

Largest legal PD unicast address.

MIN_RX_SIZE

Minimum receive-buffer size every PD must support.

OFFLINE_THRESHOLD_MS

Off-line declaration threshold.

REPLY_DELAY_MS

Default ACU reply-delay budget.

REPLY_FLAG

Reply flag set in Address when sent from PD to ACU.

SOM

Start of message marker — begins every OSDP packet header.