netlink/protocol_family/
sock_diag.rs

1// Copyright 2025 The Fuchsia Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5//! A module for handling the `NETLINK_SOCK_DIAG` API.
6
7mod eventloop;
8mod request;
9
10pub(crate) use eventloop::SockDiagEventLoop;
11pub(crate) use request::NetlinkSockDiagRequestHandler;
12
13use std::convert::Infallible as Never;
14use std::num::NonZeroU32;
15
16use linux_uapi::{
17    sknetlink_groups_SKNLGRP_INET_TCP_DESTROY, sknetlink_groups_SKNLGRP_INET_UDP_DESTROY,
18    sknetlink_groups_SKNLGRP_INET6_TCP_DESTROY, sknetlink_groups_SKNLGRP_INET6_UDP_DESTROY,
19    sknetlink_groups_SKNLGRP_NONE,
20};
21use netlink_packet_sock_diag::{SockDiagRequest, SockDiagResponse};
22
23use crate::client::{AsyncWorkCompletionWaiter, ExternalClient};
24use crate::messaging::{MessageWithPermission, Sender};
25use crate::multicast_groups::{
26    InvalidLegacyGroupsError, InvalidModernGroupError, LegacyGroups, ModernGroup,
27    MulticastCapableNetlinkFamily,
28};
29use crate::protocol_family::{NetlinkClient, ProtocolFamily};
30
31/// An implementation of the `NETLINK_SOCK_DIAG` protocol family.
32pub(crate) struct NetlinkSockDiag;
33
34impl MulticastCapableNetlinkFamily for NetlinkSockDiag {
35    #[allow(non_upper_case_globals)]
36    fn is_valid_group(ModernGroup(group): &ModernGroup) -> bool {
37        match *group {
38            sknetlink_groups_SKNLGRP_INET_TCP_DESTROY
39            | sknetlink_groups_SKNLGRP_INET_UDP_DESTROY
40            | sknetlink_groups_SKNLGRP_INET6_TCP_DESTROY
41            | sknetlink_groups_SKNLGRP_INET6_UDP_DESTROY
42            | sknetlink_groups_SKNLGRP_NONE => true,
43            _ => false,
44        }
45    }
46}
47
48#[derive(Copy, Clone, Debug, Hash, PartialEq, Eq)]
49// TODO(https://fxbug.dev/470079735): Support multicast socket closure
50// notifications.
51#[allow(dead_code)]
52pub(crate) enum NetlinkSockDiagNotifiedGroup {
53    TcpV4Destroy,
54    TcpV6Destroy,
55    UdpV4Destroy,
56    UdpV6Destroy,
57}
58
59impl MessageWithPermission for SockDiagRequest {
60    fn permission(&self) -> crate::messaging::Permission {
61        match self {
62            SockDiagRequest::InetRequest(_) | SockDiagRequest::UnixRequest(_) => {
63                crate::messaging::Permission::NetlinkSockDiagRead
64            }
65            SockDiagRequest::InetSockDestroy(_) => {
66                crate::messaging::Permission::NetlinkSockDiagDestroy
67            }
68        }
69    }
70}
71
72/// A connection to the `NETLINK_SOCK_DIAG` protocol family.
73pub struct NetlinkSockDiagClient(pub(crate) ExternalClient<NetlinkSockDiag>);
74
75impl NetlinkClient for NetlinkSockDiagClient {
76    type Request = SockDiagRequest;
77
78    fn set_pid(&self, pid: NonZeroU32) {
79        let NetlinkSockDiagClient(client) = self;
80        client.set_port_number(pid)
81    }
82
83    fn add_membership(
84        &self,
85        group: ModernGroup,
86    ) -> Result<AsyncWorkCompletionWaiter, InvalidModernGroupError> {
87        let NetlinkSockDiagClient(client) = self;
88        client.add_membership(group)
89    }
90
91    fn del_membership(&self, group: ModernGroup) -> Result<(), InvalidModernGroupError> {
92        let NetlinkSockDiagClient(client) = self;
93        client.del_membership(group)
94    }
95
96    fn set_legacy_memberships(
97        &self,
98        legacy_memberships: LegacyGroups,
99    ) -> Result<AsyncWorkCompletionWaiter, InvalidLegacyGroupsError> {
100        let NetlinkSockDiagClient(client) = self;
101        client.set_legacy_memberships(legacy_memberships)
102    }
103}
104
105impl ProtocolFamily for NetlinkSockDiag {
106    type Request = SockDiagRequest;
107    type Response = SockDiagResponse;
108    type RequestHandler<S: Sender<Self::Response>> = NetlinkSockDiagRequestHandler<S>;
109    const NAME: &'static str = "NETLINK_SOCK_DIAG";
110    type NotifiedMulticastGroup = NetlinkSockDiagNotifiedGroup;
111    type AsyncWorkItem = Never;
112
113    fn should_notify_on_group_membership_change(
114        _group: ModernGroup,
115    ) -> Option<Self::NotifiedMulticastGroup> {
116        // TODO(https://fxbug.dev/470079735): All membership changes need to
117        // be notified so the system can avoid generating socket destruction
118        // messages when nobody is listening.
119        None
120    }
121}
122
123#[cfg(test)]
124mod testutil {
125    use net_declare::{std_ip_v4, std_ip_v6};
126    use net_types::ip::{Ip, Ipv4, Ipv4Addr, Ipv6, Ipv6Addr};
127
128    pub(crate) trait TestIpExt: Ip {
129        const SRC_ADDR: Self::Addr;
130        const DST_ADDR: Self::Addr;
131        const LINUX_FAMILY: u8;
132    }
133
134    impl TestIpExt for Ipv4 {
135        const SRC_ADDR: Ipv4Addr = Ipv4Addr::new(std_ip_v4!("192.168.0.1").octets());
136        const DST_ADDR: Ipv4Addr = Ipv4Addr::new(std_ip_v4!("192.168.0.2").octets());
137        const LINUX_FAMILY: u8 = linux_uapi::AF_INET as u8;
138    }
139
140    impl TestIpExt for Ipv6 {
141        const SRC_ADDR: Ipv6Addr = Ipv6Addr::new(std_ip_v6!("2001:db8::1").segments());
142        const DST_ADDR: Ipv6Addr = Ipv6Addr::new(std_ip_v6!("2001:db8::2").segments());
143        const LINUX_FAMILY: u8 = linux_uapi::AF_INET6 as u8;
144    }
145}
netlink/protocol_family/sock_diag.rs

netlink/protocol_family/
sock_diag.rs
