hickory_proto/multicast/mod.rs
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72
// Copyright 2015-2018 Benjamin Fry <benjaminfry@me.com>
//
// Licensed under the Apache License, Version 2.0, <LICENSE-APACHE or
// https://apache.org/licenses/LICENSE-2.0> or the MIT license <LICENSE-MIT or
// https://opensource.org/licenses/MIT>, at your option. This file may not be
// copied, modified, or distributed except according to those terms.
//! Multicast protocol related components for DNS
#[cfg(feature = "tokio-runtime")]
mod mdns_client_stream;
#[cfg(feature = "tokio-runtime")]
mod mdns_stream;
#[cfg(feature = "tokio-runtime")]
pub use self::mdns_client_stream::{MdnsClientConnect, MdnsClientStream};
#[cfg(feature = "tokio-runtime")]
pub use self::mdns_stream::{MdnsStream, MDNS_IPV4, MDNS_IPV6};
/// See [rfc6762](https://tools.ietf.org/html/rfc6762#section-5) details on these different types.
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum MdnsQueryType {
/// The querier using this socket will only perform standard DNS queries over multicast. (clients only)
///
/// Effectively treats mDNS as essentially no different than any other DNS query; one request followed by one response.
/// Only one UDP socket will be created.
OneShot,
/// The querier is fully compliant with [rfc6762](https://tools.ietf.org/html/rfc6762#section-5). (servers, clients)
///
/// mDNS capable clients will sent messages with many queries, and they will expect many responses. Two UDP sockets will be
/// created, one for receiving multicast traffic, the other used for sending queries and direct responses. This requires
/// port 5353 to be available on the system (many modern OSes already have mDNSResponders running taking this port).
Continuous,
/// The querier operates under the OneShot semantics, but also joins the multicast group. (non-compliant servers, clients)
///
/// This is not defined in the mDNS RFC, but allows for a multicast client to join the group, receiving all multicast network
/// traffic. This is useful where listening for all mDNS traffic is of interest, but because another mDNS process may have
/// already taken the known port, 5353. Query responses will come from and to the standard UDP socket with a random port,
/// multicast traffic will come from the multicast socket. This will create two sockets.
OneShotJoin,
/// The querier operates under the OneShot semantics, but also joins the multicast group. (servers)
///
/// Not defined in the RFC, allows for a passive listener to receive all mDNS traffic.
Passive,
}
impl MdnsQueryType {
/// This will be sending packets, i.e. a standard UDP socket will be created
pub fn sender(self) -> bool {
match self {
Self::Passive => false,
Self::OneShot | Self::OneShotJoin => true,
Self::Continuous => true,
}
}
/// Returns true if this process can bind to *:5353
pub fn bind_on_5353(self) -> bool {
match self {
Self::OneShot | Self::OneShotJoin | Self::Passive => false,
Self::Continuous => true,
}
}
/// Returns true if this mDNS client should join, listen, on the multicast address
pub fn join_multicast(self) -> bool {
match self {
Self::OneShot => false,
Self::Continuous | Self::OneShotJoin | Self::Passive => true,
}
}
}