netlink_packet_generic/ctrl/
mod.rs

1// SPDX-License-Identifier: MIT
2
3//! Generic netlink controller implementation
4//!
5//! This module provides the definition of the controller packet.
6//! It also serves as an example for creating a generic family.
7
8use self::nlas::*;
9use crate::constants::*;
10use crate::traits::*;
11use crate::GenlHeader;
12use anyhow::Context;
13use netlink_packet_utils::nla::NlasIterator;
14use netlink_packet_utils::traits::*;
15use netlink_packet_utils::DecodeError;
16use std::convert::{TryFrom, TryInto};
17
18/// Netlink attributes for this family
19pub mod nlas;
20
21/// Command code definition of Netlink controller (nlctrl) family
22#[derive(Clone, Copy, Debug, PartialEq, Eq)]
23pub enum GenlCtrlCmd {
24    /// Notify from event
25    NewFamily,
26    /// Notify from event
27    DelFamily,
28    /// Request to get family info
29    GetFamily,
30    /// Currently unused
31    NewOps,
32    /// Currently unused
33    DelOps,
34    /// Currently unused
35    GetOps,
36    /// Notify from event
37    NewMcastGrp,
38    /// Notify from event
39    DelMcastGrp,
40    /// Currently unused
41    GetMcastGrp,
42    /// Request to get family policy
43    GetPolicy,
44}
45
46impl From<GenlCtrlCmd> for u8 {
47    fn from(cmd: GenlCtrlCmd) -> u8 {
48        use GenlCtrlCmd::*;
49        match cmd {
50            NewFamily => CTRL_CMD_NEWFAMILY,
51            DelFamily => CTRL_CMD_DELFAMILY,
52            GetFamily => CTRL_CMD_GETFAMILY,
53            NewOps => CTRL_CMD_NEWOPS,
54            DelOps => CTRL_CMD_DELOPS,
55            GetOps => CTRL_CMD_GETOPS,
56            NewMcastGrp => CTRL_CMD_NEWMCAST_GRP,
57            DelMcastGrp => CTRL_CMD_DELMCAST_GRP,
58            GetMcastGrp => CTRL_CMD_GETMCAST_GRP,
59            GetPolicy => CTRL_CMD_GETPOLICY,
60        }
61    }
62}
63
64impl TryFrom<u8> for GenlCtrlCmd {
65    type Error = DecodeError;
66
67    fn try_from(value: u8) -> Result<Self, Self::Error> {
68        use GenlCtrlCmd::*;
69        Ok(match value {
70            CTRL_CMD_NEWFAMILY => NewFamily,
71            CTRL_CMD_DELFAMILY => DelFamily,
72            CTRL_CMD_GETFAMILY => GetFamily,
73            CTRL_CMD_NEWOPS => NewOps,
74            CTRL_CMD_DELOPS => DelOps,
75            CTRL_CMD_GETOPS => GetOps,
76            CTRL_CMD_NEWMCAST_GRP => NewMcastGrp,
77            CTRL_CMD_DELMCAST_GRP => DelMcastGrp,
78            CTRL_CMD_GETMCAST_GRP => GetMcastGrp,
79            CTRL_CMD_GETPOLICY => GetPolicy,
80            cmd => return Err(DecodeError::from(format!("Unknown control command: {cmd}"))),
81        })
82    }
83}
84
85/// Payload of generic netlink controller
86#[derive(Clone, Debug, PartialEq, Eq)]
87pub struct GenlCtrl {
88    /// Command code of this message
89    pub cmd: GenlCtrlCmd,
90    /// Netlink attributes in this message
91    pub nlas: Vec<GenlCtrlAttrs>,
92}
93
94impl GenlFamily for GenlCtrl {
95    fn family_name() -> &'static str {
96        "nlctrl"
97    }
98
99    fn family_id(&self) -> u16 {
100        GENL_ID_CTRL
101    }
102
103    fn command(&self) -> u8 {
104        self.cmd.into()
105    }
106
107    fn version(&self) -> u8 {
108        2
109    }
110}
111
112impl Emitable for GenlCtrl {
113    fn emit(&self, buffer: &mut [u8]) {
114        self.nlas.as_slice().emit(buffer)
115    }
116
117    fn buffer_len(&self) -> usize {
118        self.nlas.as_slice().buffer_len()
119    }
120}
121
122impl ParseableParametrized<[u8], GenlHeader> for GenlCtrl {
123    type Error = DecodeError;
124    fn parse_with_param(buf: &[u8], header: GenlHeader) -> Result<Self, DecodeError> {
125        Ok(Self { cmd: header.cmd.try_into()?, nlas: parse_ctrlnlas(buf)? })
126    }
127}
128
129fn parse_ctrlnlas(buf: &[u8]) -> Result<Vec<GenlCtrlAttrs>, DecodeError> {
130    let nlas = NlasIterator::new(buf)
131        .map(|nla| {
132            nla.map_err(|err| DecodeError::Nla(err)).and_then(|nla| GenlCtrlAttrs::parse(&nla))
133        })
134        .collect::<Result<Vec<_>, _>>()
135        .context("failed to parse control message attributes")?;
136
137    Ok(nlas)
138}
netlink_packet_generic/ctrl/mod.rs

netlink_packet_generic/ctrl/
mod.rs
