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    GroupSupport, InvalidLegacyGroupsError, InvalidModernGroupError, LegacyGroups, ModernGroup,
27    MulticastCapableNetlinkFamily,
28};
29use crate::protocol_family::{NamedNetlinkFamily, 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 check_support(
37        ModernGroup(group): &ModernGroup,
38    ) -> Result<GroupSupport, InvalidModernGroupError> {
39        match *group {
40            sknetlink_groups_SKNLGRP_INET_TCP_DESTROY
41            | sknetlink_groups_SKNLGRP_INET_UDP_DESTROY
42            | sknetlink_groups_SKNLGRP_INET6_TCP_DESTROY
43            | sknetlink_groups_SKNLGRP_INET6_UDP_DESTROY
44            | sknetlink_groups_SKNLGRP_NONE => Ok(GroupSupport::Unsupported),
45            _ => Err(InvalidModernGroupError),
46        }
47    }
48}
49
50#[derive(Copy, Clone, Debug, Hash, PartialEq, Eq)]
51// TODO(https://fxbug.dev/470079735): Support multicast socket closure
52// notifications.
53#[allow(dead_code)]
54pub(crate) enum NetlinkSockDiagNotifiedGroup {
55    TcpV4Destroy,
56    TcpV6Destroy,
57    UdpV4Destroy,
58    UdpV6Destroy,
59}
60
61impl MessageWithPermission for SockDiagRequest {
62    fn permission(&self) -> crate::messaging::Permission {
63        match self {
64            SockDiagRequest::InetRequest(_) | SockDiagRequest::UnixRequest(_) => {
65                crate::messaging::Permission::NetlinkSockDiagRead
66            }
67            SockDiagRequest::InetSockDestroy(_) => {
68                crate::messaging::Permission::NetlinkSockDiagDestroy
69            }
70        }
71    }
72}
73
74/// A connection to the `NETLINK_SOCK_DIAG` protocol family.
75pub struct NetlinkSockDiagClient(pub(crate) ExternalClient<NetlinkSockDiag>);
76
77impl NetlinkClient for NetlinkSockDiagClient {
78    type Request = SockDiagRequest;
79
80    fn set_pid(&self, pid: NonZeroU32) {
81        let NetlinkSockDiagClient(client) = self;
82        client.set_port_number(pid)
83    }
84
85    fn add_membership(
86        &self,
87        group: ModernGroup,
88    ) -> Result<AsyncWorkCompletionWaiter, InvalidModernGroupError> {
89        let NetlinkSockDiagClient(client) = self;
90        client.add_membership(group)
91    }
92
93    fn del_membership(&self, group: ModernGroup) -> Result<(), InvalidModernGroupError> {
94        let NetlinkSockDiagClient(client) = self;
95        client.del_membership(group)
96    }
97
98    fn set_legacy_memberships(
99        &self,
100        legacy_memberships: LegacyGroups,
101    ) -> Result<AsyncWorkCompletionWaiter, InvalidLegacyGroupsError> {
102        let NetlinkSockDiagClient(client) = self;
103        client.set_legacy_memberships(legacy_memberships)
104    }
105}
106
107impl NamedNetlinkFamily for NetlinkSockDiag {
108    const NAME: &'static str = "NETLINK_SOCK_DIAG";
109}
110
111impl ProtocolFamily for NetlinkSockDiag {
112    type Request = SockDiagRequest;
113    type Response = SockDiagResponse;
114    type RequestHandler<S: Sender<Self::Response>> = NetlinkSockDiagRequestHandler<S>;
115    type NotifiedMulticastGroup = NetlinkSockDiagNotifiedGroup;
116    type AsyncWorkItem = Never;
117
118    fn should_notify_on_group_membership_change(
119        _group: ModernGroup,
120    ) -> Option<Self::NotifiedMulticastGroup> {
121        // TODO(https://fxbug.dev/470079735): All membership changes need to
122        // be notified so the system can avoid generating socket destruction
123        // messages when nobody is listening.
124        None
125    }
126}
127
128#[cfg(test)]
129mod testutil {
130    use net_declare::{std_ip_v4, std_ip_v6};
131    use net_types::ip::{Ip, Ipv4, Ipv4Addr, Ipv6, Ipv6Addr};
132
133    pub(crate) trait TestIpExt: Ip {
134        const SRC_ADDR: Self::Addr;
135        const DST_ADDR: Self::Addr;
136        const LINUX_FAMILY: u8;
137    }
138
139    impl TestIpExt for Ipv4 {
140        const SRC_ADDR: Ipv4Addr = Ipv4Addr::new(std_ip_v4!("192.168.0.1").octets());
141        const DST_ADDR: Ipv4Addr = Ipv4Addr::new(std_ip_v4!("192.168.0.2").octets());
142        const LINUX_FAMILY: u8 = linux_uapi::AF_INET as u8;
143    }
144
145    impl TestIpExt for Ipv6 {
146        const SRC_ADDR: Ipv6Addr = Ipv6Addr::new(std_ip_v6!("2001:db8::1").segments());
147        const DST_ADDR: Ipv6Addr = Ipv6Addr::new(std_ip_v6!("2001:db8::2").segments());
148        const LINUX_FAMILY: u8 = linux_uapi::AF_INET6 as u8;
149    }
150}
netlink/protocol_family/sock_diag.rs

netlink/protocol_family/
sock_diag.rs
