Support setting the bond port settings of the device

Add support for setting device's bond port settings and also provide
the example for validating the support.

Notice that the port priority setting is supported in kernel since
v6.0.

Signed-off-by: Wen Liang <liangwen12year@gmail.com>

examples/get_bond_port_settings.rs

@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: MIT
+
+use futures::stream::TryStreamExt;
+use rtnetlink::{new_connection, Error, Handle};
+use std::env;
+
+#[tokio::main]
+async fn main() -> Result<(), ()> {
+    let args: Vec<String> = env::args().collect();
+    if args.len() != 2 {
+        usage();
+        return Ok(());
+    }
+    let link_name = &args[1];
+
+    let (connection, handle, _) = new_connection().unwrap();
+    tokio::spawn(connection);
+
+    let linkname = link_name.to_string();
+    println!("dumping bond port settings for link \"{linkname}\"");
+
+    if let Err(e) = dump_bond_port_settings(handle, linkname).await {
+        eprintln!("{e}");
+    }
+
+    Ok(())
+}
+
+async fn dump_bond_port_settings(
+    handle: Handle,
+    linkname: String,
+) -> Result<(), Error> {
+    let mut links = handle.link().get().match_name(linkname.clone()).execute();
+    if let Some(_link) = links.try_next().await? {
+        let mut link_messgage =
+            handle.link().get().match_name(linkname).execute();
+        while let Some(msg) = link_messgage.try_next().await? {
+            println!("{msg:?}");
+        }
+        Ok(())
+    } else {
+        eprintln!("link {linkname} not found");
+        Ok(())
+    }
+}
+
+fn usage() {
+    eprintln!(
+        "usage:
+    cargo run --example get_bond_port_settings -- <link name>
+
+Note that you need to run this program as root. Instead of running cargo as root,
+build the example normally:
+
+    cd netlink-ip ; cargo build --example get_bond_port_settings
+
+Then find the binary in the target directory:
+
+    cd ../target/debug/example ; sudo ./get_bond_port_settings <link_name>"
+    );
+}

examples/set_bond_port_settings.rs

@@ -0,0 +1,61 @@
+// SPDX-License-Identifier: MIT
+
+use futures::stream::TryStreamExt;
+use rtnetlink::{new_connection, Error, Handle};
+use std::env;
+
+#[tokio::main]
+async fn main() -> Result<(), String> {
+    let args: Vec<String> = env::args().collect();
+    if args.len() != 2 {
+        usage();
+        return Ok(());
+    }
+    let link_name = &args[1];
+
+    let (connection, handle, _) = new_connection().unwrap();
+    tokio::spawn(connection);
+
+    set_bond_port_settings(handle, link_name.to_string())
+        .await
+        .map_err(|e| format!("{e}"))
+}
+// The bond port priority is only supported to set when bonding mode is
+// active-backup(1) or balance-tlb (5) or balance-alb (6)
+async fn set_bond_port_settings(
+    handle: Handle,
+    name: String,
+) -> Result<(), Error> {
+    let mut links = handle.link().get().match_name(name.clone()).execute();
+    if let Some(link) = links.try_next().await? {
+        // This is equivalent to `ip link set name NAME type bond_slave queue_id
+        // 0 prio 1`. The port priority setting is supported in kernel
+        // since v6.0
+        handle
+            .link()
+            .set_bond_port(link.header.index)
+            .queue_id(0)
+            .prio(1)
+            .execute()
+            .await?
+    } else {
+        println!("no link link {name} found");
+    }
+    Ok(())
+}
+
+fn usage() {
+    eprintln!(
+        "usage:
+    cargo run --example set_bond_port_settings -- <link name>
+
+Note that you need to run this program as root. Instead of running cargo as root,
+build the example normally:
+
+    cd netlink-ip ; cargo build --example set_bond_port_settings
+
+Then find the binary in the target directory:
+
+    cd ../target/debug/example ; sudo ./set_bond_port_settings <link_name>"
+    );
+}

src/link/handle.rs

@@ -1,8 +1,8 @@
 // SPDX-License-Identifier: MIT
 
 use super::{
-    LinkAddRequest, LinkDelPropRequest, LinkDelRequest, LinkGetRequest,
-    LinkNewPropRequest, LinkSetRequest,
+    BondPortSetRequest, LinkAddRequest, LinkDelPropRequest, LinkDelRequest,
+    LinkGetRequest, LinkNewPropRequest, LinkSetRequest,
 };
 use crate::Handle;
 
@@ -37,4 +37,8 @@ impl LinkHandle {
     pub fn get(&mut self) -> LinkGetRequest {
         LinkGetRequest::new(self.0.clone())
     }
+
+    pub fn set_bond_port(&mut self, index: u32) -> BondPortSetRequest {
+        BondPortSetRequest::new(self.0.clone(), index)
+    }
 }

src/link/mod.rs

@@ -15,6 +15,9 @@ pub use self::get::*;
 mod set;
 pub use self::set::*;
 
+mod set_bond_port;
+pub use self::set_bond_port::*;
+
 mod property_add;
 pub use self::property_add::*;
 

src/link/set_bond_port.rs

@@ -0,0 +1,71 @@
+// SPDX-License-Identifier: MIT
+
+use futures::stream::StreamExt;
+use netlink_packet_core::{NetlinkMessage, NLM_F_ACK, NLM_F_REQUEST};
+use netlink_packet_route::{
+    link::nlas::{Info, InfoBondPort, InfoPortData, InfoPortKind, Nla},
+    LinkMessage, RtnlMessage,
+};
+
+use crate::{try_nl, Error, Handle};
+
+pub struct BondPortSetRequest {
+    handle: Handle,
+    index: u32,
+    port_nlas: Vec<InfoBondPort>,
+}
+
+impl BondPortSetRequest {
+    pub(crate) fn new(handle: Handle, index: u32) -> Self {
+        BondPortSetRequest {
+            handle,
+            index,
+            port_nlas: Vec::new(),
+        }
+    }
+
+    /// Execute the request.
+    pub async fn execute(self) -> Result<(), Error> {
+        let BondPortSetRequest {
+            mut handle,
+            index,
+            port_nlas,
+        } = self;
+
+        let mut message = LinkMessage::default();
+        message.header.index = index;
+        message.nlas.push(Nla::Info(vec![
+            Info::PortKind(InfoPortKind::Bond),
+            Info::PortData(InfoPortData::BondPort(port_nlas)),
+        ]));
+
+        let mut req = NetlinkMessage::from(RtnlMessage::NewLink(message));
+        req.header.flags = NLM_F_REQUEST | NLM_F_ACK;
+
+        let mut response = handle.request(req)?;
+        while let Some(message) = response.next().await {
+            try_nl!(message);
+        }
+        Ok(())
+    }
+
+    /// Return a mutable reference to the Vec<InfoBondPort>
+    pub fn info_port_nlas_mut(&mut self) -> &mut Vec<InfoBondPort> {
+        &mut self.port_nlas
+    }
+
+    /// Adds the `queue_id` attribute to the bond port
+    /// This is equivalent to
+    /// `ip link set name NAME type bond_slave queue_id QUEUE_ID`.
+    pub fn queue_id(mut self, queue_id: u16) -> Self {
+        self.port_nlas.push(InfoBondPort::QueueId(queue_id));
+        self
+    }
+
+    /// Adds the `prio` attribute to the bond port
+    /// This is equivalent to `ip link set name NAME type bond_slave prio PRIO`.
+    pub fn prio(mut self, prio: i32) -> Self {
+        self.port_nlas.push(InfoBondPort::Prio(prio));
+        self
+    }
+}