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netlink_bindings/
traits.rs

1#[derive(Debug, Clone, Copy, PartialEq, Eq)]
2pub enum Protocol {
3    /// Netlink-raw protocol
4    Raw {
5        /// Value supplied to socket(2)
6        protonum: u16,
7        /// Value of `type` field in the message header
8        request_type: u16,
9    },
10    /// Generic netlink protocol
11    Generic(&'static [u8]),
12}
13
14/// A trait describing how to handle a particular request.
15/// It designed to be used by a netlink socket implementation.
16pub trait NetlinkRequest {
17    /// Netlink protocol to use
18    fn protocol(&self) -> Protocol;
19
20    /// Additional `flags` specified in the message header
21    fn flags(&self) -> u16;
22
23    /// Encoded payload of the message (without message header)
24    fn payload(&self) -> &[u8];
25
26    // type RequestType<'buf>;
27    // fn decode_request(buf: &[u8]) -> Self::RequestType<'_>;
28
29    type ReplyType<'buf>;
30    fn decode_reply(buf: &[u8]) -> Self::ReplyType<'_>;
31
32    /// Lookup an attribute and it's parents in the request payload by offset
33    fn lookup(
34        buf: &[u8],
35        offset: usize,
36        missing_type: Option<u16>,
37    ) -> (Vec<(&'static str, usize)>, Option<&'static str>) {
38        let _ = buf;
39        let _ = offset;
40        let _ = missing_type;
41        (Vec::new(), None)
42    }
43}
44
45/// Function signature of [`NetlinkRequest::lookup`]
46pub type LookupFn =
47    fn(&[u8], usize, Option<u16>) -> (Vec<(&'static str, usize)>, Option<&'static str>);
48
49/// A chain of requests encoded into the single buffer (experimental)
50pub trait NetlinkChained {
51    fn protonum(&self) -> u16;
52
53    /// Encoded payload of the messages (including message headers)
54    fn payload(&self) -> &[u8];
55
56    /// Number of messages in the chain
57    fn chain_len(&self) -> usize;
58
59    fn get_index(&self, seq: u32) -> Option<usize>;
60
61    fn name(&self, index: usize) -> &'static str;
62
63    fn lookup(&self, index: usize) -> LookupFn {
64        let _ = index;
65        |_, _, _| Default::default()
66    }
67
68    /// Packet supports ack on success with NLM_F_ACK (assumed true by default).
69    /// To date, this's only used to workaround a bug in nftables prior to linux 6.10.
70    ///
71    /// Caller sequentially peeks indexes 0..chain_len() until it encounters None.
72    #[doc(hidden)]
73    fn supports_ack(&self, index: usize) -> Option<bool> {
74        let _ = index;
75        None
76    }
77}