Merge pull request #491 from LibreQoE/preflight-bridge-check

Preflight bridge check with relaxed interface status checks

src/rust/lqos_config/src/etc/mod.rs

@@ -117,6 +117,24 @@ pub fn update_config(new_config: &Config) -> Result<(), LibreQoSConfigError> {
     Ok(())
 }
 
+/// Helper function that disables the XDP bridge in the LIVE, CACHED
+/// configuration --- it does NOT save the changes to disk. This is
+/// intended for use when the XDP bridge is disabled by pre-flight
+/// because of a Linux bridge.
+pub fn disable_xdp_bridge() -> Result<(), LibreQoSConfigError> {
+    let mut config = load_config()?;
+    let mut lock = CONFIG.lock().unwrap();
+
+    if let Some(bridge) = &mut config.bridge {
+        bridge.use_xdp_bridge = false;
+    }
+
+    // Write the lock
+    *lock = Some(config);
+
+    Ok(())
+}
+
 #[derive(Debug, Error)]
 pub enum LibreQoSConfigError {
     #[error("Unable to read /etc/lqos.conf. See other errors for details.")]
@@ -140,3 +158,4 @@ pub enum LibreQoSConfigError {
     #[error("Unable to serialize config")]
     SerializeError,
 }
+

src/rust/lqos_config/src/lib.rs

@@ -13,7 +13,7 @@ mod program_control;
 mod shaped_devices;
 
 pub use authentication::{UserRole, WebUsers};
-pub use etc::{load_config, Config, enable_long_term_stats, Tunables, BridgeConfig, update_config};
+pub use etc::{load_config, Config, enable_long_term_stats, Tunables, BridgeConfig, update_config, disable_xdp_bridge};
 pub use network_json::{NetworkJson, NetworkJsonNode, NetworkJsonTransport};
 pub use program_control::load_libreqos;
 pub use shaped_devices::{ConfigShapedDevices, ShapedDevice};

src/rust/lqosd/src/preflight_checks.rs

@@ -1,7 +1,8 @@
-use std::path::Path;
+use std::{path::Path, process::Command};
 
 use anyhow::Result;
 use log::{error, info};
+use lqos_config::Config;
 use lqos_sys::interface_name_to_index;
 
 fn check_queues(interface: &str) -> Result<()> {
@@ -42,6 +43,99 @@ fn check_queues(interface: &str) -> Result<()> {
     Ok(())
 }
 
+#[derive(Debug)]
+pub struct IpLinkInterface {
+    pub name: String,
+    pub index: u32,
+    pub operstate: String,
+    pub link_type: String,
+    pub master: Option<String>,
+}
+
+pub fn get_interfaces_from_ip_link() -> Result<Vec<IpLinkInterface>> {
+    let output = Command::new("/sbin/ip")
+        .args(["-j", "link"])
+        .output()?;
+    let output = String::from_utf8(output.stdout)?;
+    let output_json = serde_json::from_str::<serde_json::Value>(&output)?;
+
+    let mut interfaces = Vec::new();
+    for interface in output_json.as_array().unwrap() {
+        let name = interface["ifname"].as_str().unwrap().to_string();
+        let index = interface["ifindex"].as_u64().unwrap() as u32;
+        let operstate = interface["operstate"].as_str().unwrap().to_string();
+        let link_type = interface["link_type"].as_str().unwrap().to_string();
+        let master = interface["master"].as_str().map(|s| s.to_string());
+
+        interfaces.push(IpLinkInterface {
+            name,
+            index,
+            operstate,
+            link_type,
+            master,
+        });
+    }
+
+    Ok(interfaces)
+}
+
+fn check_interface_status(config: &Config, interfaces: &[IpLinkInterface]) -> Result<()> {
+    if let Some(stick) = &config.single_interface {
+        if let Some(iface) = interfaces.iter().find(|i| i.name == stick.interface) {
+            info!("Interface {} is in status: {}", stick.interface, iface.operstate);
+        }
+    } else if let Some(bridge) = &config.bridge {
+        if let Some(iface) = interfaces.iter().find(|i| i.name == bridge.to_internet) {
+            info!("Interface {} is in status: {}", iface.name, iface.operstate);
+        }
+        if let Some(iface) = interfaces.iter().find(|i| i.name == bridge.to_network) {
+            info!("Interface {} is in status: {}", iface.name, iface.operstate);
+        }
+    } else {
+        error!("You MUST have either a single interface or a bridge defined in the configuration file.");
+        anyhow::bail!("You MUST have either a single interface or a bridge defined in the configuration file.");
+    }
+
+    Ok(())
+}
+
+fn check_bridge_status(config: &Config, interfaces: &[IpLinkInterface]) -> Result<()> {
+    // On a stick mode is bridge-free
+    if config.on_a_stick_mode() {        
+        return Ok(());
+    }
+
+    // Is the XDP bridge enabled?
+    if let Some(bridge) = &config.bridge {
+        if bridge.use_xdp_bridge {
+            for bridge_if in interfaces
+                .iter()
+                .filter(|bridge_if| bridge_if.link_type == "ether" && bridge_if.operstate == "UP") 
+            {
+                // We found a bridge. Check member interfaces to check that it does NOT include any XDP
+                // bridge members.
+                let in_bridge: Vec<&IpLinkInterface> = interfaces
+                    .iter()
+                    .filter(|member_if| {
+                        if let Some(master) = &member_if.master {
+                            master == &bridge_if.name
+                        } else {
+                            false
+                        }
+                    })
+                    .filter(|member_if| member_if.name == config.internet_interface() || member_if.name == config.isp_interface())
+                    .collect();
+
+                if in_bridge.len() == 2 {
+                    error!("Bridge ({}) contains both the internet and ISP interfaces, and you have the xdp_bridge enabled. This is not supported.", bridge_if.name);
+                    anyhow::bail!("Bridge {} contains both the internet and ISP interfaces. This is not supported.", bridge_if.name);                    
+                }
+            }
+        }
+    }
+    Ok(())
+}
+
 /// Runs a series of preflight checks to ensure that the configuration is sane
 pub fn preflight_checks() -> Result<()> {
     info!("Sanity checking configuration...");
@@ -78,6 +172,19 @@ pub fn preflight_checks() -> Result<()> {
         check_queues(&config.isp_interface())?;
     }
 
+    // Obtain the "IP link" output
+    let interfaces = get_interfaces_from_ip_link()?;
+
+    // Are the interfaces up?
+    check_interface_status(&config, &interfaces)?;
+
+    // Does the bridge system make sense?
+    if check_bridge_status(&config, &interfaces).is_err() {
+        log::warn!("Disabling XDP bridge");
+        lqos_config::disable_xdp_bridge()?;
+        log::warn!("XDP bridge disabled in ACTIVE config. Please fix the configuration file.");
+    };
+
     info!("Sanity checks passed");
 
     Ok(())