feat(interfaces): listen on all interfaces by default

Specifying an interface is now optional.
The interface is shown in the connections table.

11 files changed, 235 insertions, 207 deletions

diff --git a/src/display/components/table.rs b/src/display/components/table.rs
index 74e207a..aef914e 100644
--- a/src/display/components/table.rs
+++ b/src/display/components/table.rs
@@ -64,7 +64,7 @@ impl<'a> Table<'a> {
             .iter()
             .map(|(connection, connection_data)| {
                 vec![
-                    display_connection_string(&connection, &ip_to_host),
+                    display_connection_string(&connection, &ip_to_host, &connection_data.interface),
                     connection_data.process_name.to_string(),
                     display_upload_and_download(*connection_data),
                 ]
diff --git a/src/display/ui.rs b/src/display/ui.rs
index 3fcb092..fd137bc 100644
--- a/src/display/ui.rs
+++ b/src/display/ui.rs
@@ -53,7 +53,11 @@ where
             write_to_stdout(format!(
                 "connection: <{}> {} up/down Bps: {}/{} process: \"{}\"",
                 timestamp,
-                display_connection_string(connection, ip_to_host),
+                display_connection_string(
+                    connection,
+                    ip_to_host,
+                    &connection_network_data.interface
+                ),
                 connection_network_data.total_bytes_uploaded,
                 connection_network_data.total_bytes_downloaded,
                 connection_network_data.process_name
diff --git a/src/display/ui_state.rs b/src/display/ui_state.rs
index a027ff4..d374c01 100644
--- a/src/display/ui_state.rs
+++ b/src/display/ui_state.rs
@@ -20,6 +20,7 @@ pub struct ConnectionData {
     pub total_bytes_downloaded: u128,
     pub total_bytes_uploaded: u128,
     pub process_name: String,
+    pub interface: String,
 }
 
 impl Bandwidth for ConnectionData {
@@ -52,7 +53,7 @@ pub struct UIState {
 impl UIState {
     pub fn new(
         connections_to_procs: HashMap<Connection, String>,
-        network_utilization: Utilization,
+        mut network_utilization: Utilization,
     ) -> Self {
         let mut processes: BTreeMap<String, NetworkData> = BTreeMap::new();
         let mut remote_addresses: BTreeMap<Ipv4Addr, NetworkData> = BTreeMap::new();
@@ -60,32 +61,27 @@ impl UIState {
         let mut total_bytes_downloaded: u128 = 0;
         let mut total_bytes_uploaded: u128 = 0;
         for (connection, process_name) in connections_to_procs {
-            if let Some(connection_bandwidth_utilization) =
-                network_utilization.connections.get(&connection)
-            {
+            if let Some(connection_info) = network_utilization.connections.remove(&connection) {
                 let data_for_remote_address = remote_addresses
                     .entry(connection.remote_socket.ip)
                     .or_default();
                 let connection_data = connections.entry(connection).or_default();
                 let data_for_process = processes.entry(process_name.clone()).or_default();
 
-                data_for_process.total_bytes_downloaded +=
-                    &connection_bandwidth_utilization.total_bytes_downloaded;
-                data_for_process.total_bytes_uploaded +=
-                    &connection_bandwidth_utilization.total_bytes_uploaded;
+                data_for_process.total_bytes_downloaded += connection_info.total_bytes_downloaded;
+                data_for_process.total_bytes_uploaded += connection_info.total_bytes_uploaded;
                 data_for_process.connection_count += 1;
-                connection_data.total_bytes_downloaded +=
-                    &connection_bandwidth_utilization.total_bytes_downloaded;
-                connection_data.total_bytes_uploaded +=
-                    &connection_bandwidth_utilization.total_bytes_uploaded;
+                connection_data.total_bytes_downloaded += connection_info.total_bytes_downloaded;
+                connection_data.total_bytes_uploaded += connection_info.total_bytes_uploaded;
                 connection_data.process_name = process_name;
+                connection_data.interface = connection_info.interface;
                 data_for_remote_address.total_bytes_downloaded +=
-                    connection_bandwidth_utilization.total_bytes_downloaded;
+                    connection_info.total_bytes_downloaded;
                 data_for_remote_address.total_bytes_uploaded +=
-                    connection_bandwidth_utilization.total_bytes_uploaded;
+                    connection_info.total_bytes_uploaded;
                 data_for_remote_address.connection_count += 1;
-                total_bytes_downloaded += connection_bandwidth_utilization.total_bytes_downloaded;
-                total_bytes_uploaded += connection_bandwidth_utilization.total_bytes_uploaded;
+                total_bytes_downloaded += connection_info.total_bytes_downloaded;
+                total_bytes_uploaded += connection_info.total_bytes_uploaded;
             }
         }
         UIState {
diff --git a/src/main.rs b/src/main.rs
index 9022cfa..34cc09c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -36,7 +36,7 @@ use structopt::StructOpt;
 pub struct Opt {
     #[structopt(short, long)]
     /// The network interface to listen on, eg. eth0
-    interface: String,
+    interface: Option<String>,
     #[structopt(short, long)]
     /// Machine friendlier output
     raw: bool,
@@ -78,8 +78,8 @@ fn try_main() -> Result<(), failure::Error> {
 }
 
 pub struct OsInputOutput {
-    pub network_interface: NetworkInterface,
-    pub network_frames: Box<dyn DataLinkReceiver>,
+    pub network_interfaces: Vec<NetworkInterface>,
+    pub network_frames: Vec<Box<dyn DataLinkReceiver>>,
     pub get_open_sockets: fn() -> HashMap<Connection, String>,
     pub keyboard_events: Box<dyn Iterator<Item = Event> + Send>,
     pub dns_client: Option<dns::Client>,
@@ -105,7 +105,13 @@ where
 
     let raw_mode = opts.raw;
 
-    let mut sniffer = Sniffer::new(os_input.network_interface, os_input.network_frames);
+    let mut sniffers = os_input
+        .network_interfaces
+        .into_iter()
+        .zip(os_input.network_frames.into_iter())
+        .map(|(iface, frames)| Sniffer::new(iface, frames))
+        .collect::<Vec<Sniffer>>();
+
     let network_utilization = Arc::new(Mutex::new(Utilization::new()));
     let ui = Arc::new(Mutex::new(Ui::new(terminal_backend)));
 
@@ -196,10 +202,13 @@ where
     active_threads.push(
         thread::Builder::new()
             .name("sniffing_handler".to_string())
-            .spawn(move || {
-                while running.load(Ordering::Acquire) {
+            .spawn(move || 'sniffing: loop {
+                for sniffer in sniffers.iter_mut() {
                     if let Some(segment) = sniffer.next() {
-                        network_utilization.lock().unwrap().update(&segment)
+                        network_utilization.lock().unwrap().update(segment);
+                    }
+                    if !running.load(Ordering::Acquire) {
+                        break 'sniffing;
                     }
                 }
             })
diff --git a/src/network/connection.rs b/src/network/connection.rs
index f931d54..bd42525 100644
--- a/src/network/connection.rs
+++ b/src/network/connection.rs
@@ -52,9 +52,11 @@ pub fn display_ip_or_host(ip: Ipv4Addr, ip_to_host: &HashMap<Ipv4Addr, String>)
 pub fn display_connection_string(
     connection: &Connection,
     ip_to_host: &HashMap<Ipv4Addr, String>,
+    interface: &str,
 ) -> String {
     format!(
-        ":{} => {}:{} ({})",
+        "<{}>:{} => {}:{} ({})",
+        interface,
         connection.local_port,
         display_ip_or_host(connection.remote_socket.ip, ip_to_host),
         connection.remote_socket.port,
diff --git a/src/network/sniffer.rs b/src/network/sniffer.rs
index 3ec6886..7b2d0b0 100644
--- a/src/network/sniffer.rs
+++ b/src/network/sniffer.rs
@@ -14,6 +14,7 @@ use ::std::net::{IpAddr, SocketAddr};
 use crate::network::{Connection, Protocol};
 
 pub struct Segment {
+    pub interface: String,
     pub connection: Connection,
     pub direction: Direction,
     pub data_length: u128,
@@ -81,6 +82,7 @@ impl Sniffer {
                         }
                         _ => return None,
                     };
+                let interface = self.network_interface.name.clone();
                 let direction = Direction::new(&self.network_interface.ips, &ip_packet);
                 let from = SocketAddr::new(IpAddr::V4(ip_packet.get_source()), source_port);
                 let to = SocketAddr::new(IpAddr::V4(ip_packet.get_destination()), destination_port);
@@ -90,6 +92,7 @@ impl Sniffer {
                     Direction::Upload => Connection::new(to, source_port, protocol)?,
                 };
                 Some(Segment {
+                    interface,
                     connection,
                     data_length,
                     direction,
diff --git a/src/network/utilization.rs b/src/network/utilization.rs
index cb0f12b..6cd732f 100644
--- a/src/network/utilization.rs
+++ b/src/network/utilization.rs
@@ -3,14 +3,15 @@ use crate::network::{Connection, Direction, Segment};
 use ::std::collections::HashMap;
 
 #[derive(Clone)]
-pub struct TotalBandwidth {
+pub struct ConnectionInfo {
+    pub interface: String,
     pub total_bytes_downloaded: u128,
     pub total_bytes_uploaded: u128,
 }
 
 #[derive(Clone)]
 pub struct Utilization {
-    pub connections: HashMap<Connection, TotalBandwidth>,
+    pub connections: HashMap<Connection, ConnectionInfo>,
 }
 
 impl Utilization {
@@ -23,14 +24,15 @@ impl Utilization {
         self.connections.clear();
         clone
     }
-    pub fn update(&mut self, seg: &Segment) {
-        let total_bandwidth =
-            self.connections
-                .entry(seg.connection.clone())
-                .or_insert(TotalBandwidth {
-                    total_bytes_downloaded: 0,
-                    total_bytes_uploaded: 0,
-                });
+    pub fn update(&mut self, seg: Segment) {
+        let total_bandwidth = self
+            .connections
+            .entry(seg.connection)
+            .or_insert(ConnectionInfo {
+                interface: seg.interface,
+                total_bytes_downloaded: 0,
+                total_bytes_uploaded: 0,
+            });
         match seg.direction {
             Direction::Download => {
                 total_bandwidth.total_bytes_downloaded += seg.data_length;
diff --git a/src/os/shared.rs b/src/os/shared.rs
index 8947ecb..3a9aeee 100644
--- a/src/os/shared.rs
+++ b/src/os/shared.rs
@@ -34,11 +34,11 @@ fn get_datalink_channel(
     interface: &NetworkInterface,
 ) -> Result<Box<dyn DataLinkReceiver>, failure::Error> {
     let mut config = Config::default();
-    config.read_timeout = Some(time::Duration::new(0, 1));
+    config.read_timeout = Some(time::Duration::new(0, 2_000_000));
     match datalink::channel(interface, config) {
         Ok(Ethernet(_tx, rx)) => Ok(rx),
         Ok(_) => failure::bail!("Unknown interface type"),
-        Err(e) => failure::bail!("Failed to listen to network interface: {}", e),
+        Err(e) => failure::bail!("Failed to listen on network interface: {}", e),
     }
 }
 
@@ -76,15 +76,27 @@ fn create_write_to_stdout() -> Box<dyn FnMut(String) + Send> {
     })
 }
 
-pub fn get_input(interface_name: &str, resolve: bool) -> Result<OsInputOutput, failure::Error> {
-    let keyboard_events = Box::new(KeyboardEvents);
-    let network_interface = match get_interface(interface_name) {
-        Some(interface) => interface,
-        None => {
-            failure::bail!("Cannot find interface {}", interface_name);
+pub fn get_input(
+    interface_name: &Option<String>,
+    resolve: bool,
+) -> Result<OsInputOutput, failure::Error> {
+    let network_interfaces = if let Some(name) = interface_name {
+        match get_interface(&name) {
+            Some(interface) => vec![interface],
+            None => {
+                failure::bail!("Cannot find interface {}", name);
+            }
         }
+    } else {
+        datalink::interfaces()
     };
-    let network_frames = get_datalink_channel(&network_interface)?;
+
+    let network_frames = network_interfaces
+        .iter()
+        .map(|iface| get_datalink_channel(iface))
+        .collect::<Result<Vec<_>, _>>()?;
+
+    let keyboard_events = Box::new(KeyboardEvents);
     let write_to_stdout = create_write_to_stdout();
     let (on_winch, cleanup) = sigwinch();
     let dns_client = if resolve {
@@ -96,7 +108,7 @@ pub fn get_input(interface_name: &str, resolve: bool) -> Result<OsInputOutput, f
     };
 
     Ok(OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
diff --git a/src/tests/cases/raw_mode.rs b/src/tests/cases/raw_mode.rs
index f0989ca..54cea9e 100644
--- a/src/tests/cases/raw_mode.rs
+++ b/src/tests/cases/raw_mode.rs
@@ -1,5 +1,5 @@
 use crate::tests::fakes::{
-    create_fake_dns_client, create_fake_on_winch, get_interface, get_open_sockets, KeyboardEvents,
+    create_fake_dns_client, create_fake_on_winch, get_interfaces, get_open_sockets, KeyboardEvents,
     NetworkFrames, TestBackend,
 };
 
@@ -65,13 +65,13 @@ fn one_packet_of_traffic() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![Some(build_tcp_packet(
+    let network_frames = vec![NetworkFrames::new(vec![Some(build_tcp_packet(
         "10.0.0.2",
         "1.1.1.1",
         443,
         12345,
         b"I am a fake tcp packet",
-    ))]);
+    ))])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -84,7 +84,7 @@ fn one_packet_of_traffic() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
@@ -98,7 +98,7 @@ fn one_packet_of_traffic() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -108,7 +108,7 @@ fn one_packet_of_traffic() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -125,7 +125,7 @@ fn bi_directional_traffic() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "10.0.0.2",
             "1.1.1.1",
@@ -140,7 +140,7 @@ fn bi_directional_traffic() {
             443,
             b"I am a fake tcp download packet",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -153,7 +153,7 @@ fn bi_directional_traffic() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
@@ -167,7 +167,7 @@ fn bi_directional_traffic() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -177,7 +177,7 @@ fn bi_directional_traffic() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -194,7 +194,7 @@ fn multiple_packets_of_traffic_from_different_connections() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "1.1.1.1",
             "10.0.0.2",
@@ -209,7 +209,7 @@ fn multiple_packets_of_traffic_from_different_connections() {
             443,
             b"I come from 2.2.2.2",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -224,7 +224,7 @@ fn multiple_packets_of_traffic_from_different_connections() {
     );
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let stdout = Arc::new(Mutex::new(Vec::new()));
     let write_to_stdout = Box::new({
@@ -236,7 +236,7 @@ fn multiple_packets_of_traffic_from_different_connections() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         on_winch,
@@ -246,7 +246,7 @@ fn multiple_packets_of_traffic_from_different_connections() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -263,7 +263,7 @@ fn multiple_packets_of_traffic_from_single_connection() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "1.1.1.1",
             "10.0.0.2",
@@ -278,7 +278,7 @@ fn multiple_packets_of_traffic_from_single_connection() {
             443,
             b"I've come from 1.1.1.1 too!",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -291,7 +291,7 @@ fn multiple_packets_of_traffic_from_single_connection() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
@@ -305,7 +305,7 @@ fn multiple_packets_of_traffic_from_single_connection() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -315,7 +315,7 @@ fn multiple_packets_of_traffic_from_single_connection() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -332,7 +332,7 @@ fn one_process_with_multiple_connections() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "1.1.1.1",
             "10.0.0.2",
@@ -347,7 +347,7 @@ fn one_process_with_multiple_connections() {
             443,
             b"Funny that, I'm from 3.3.3.3",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -360,7 +360,7 @@ fn one_process_with_multiple_connections() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
@@ -374,7 +374,7 @@ fn one_process_with_multiple_connections() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -384,7 +384,7 @@ fn one_process_with_multiple_connections() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -401,7 +401,7 @@ fn multiple_processes_with_multiple_connections() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "1.1.1.1",
             "10.0.0.2",
@@ -430,7 +430,7 @@ fn multiple_processes_with_multiple_connections() {
             443,
             b"I'm partial to 4.4.4.4",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -443,7 +443,7 @@ fn multiple_processes_with_multiple_connections() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
@@ -457,7 +457,7 @@ fn multiple_processes_with_multiple_connections() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -467,7 +467,7 @@ fn multiple_processes_with_multiple_connections() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -484,7 +484,7 @@ fn multiple_connections_from_remote_address() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "1.1.1.1",
             "10.0.0.2",
@@ -499,7 +499,7 @@ fn multiple_connections_from_remote_address() {
             443,
             b"Me too, but on a different port",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -512,7 +512,7 @@ fn multiple_connections_from_remote_address() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
@@ -526,7 +526,7 @@ fn multiple_connections_from_remote_address() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -536,7 +536,7 @@ fn multiple_connections_from_remote_address() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -554,7 +554,7 @@ fn sustained_traffic_from_one_process() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "1.1.1.1",
             "10.0.0.2",
@@ -570,7 +570,7 @@ fn sustained_traffic_from_one_process() {
             443,
             b"Same here, but one second later",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -583,7 +583,7 @@ fn sustained_traffic_from_one_process() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
@@ -597,7 +597,7 @@ fn sustained_traffic_from_one_process() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -607,7 +607,7 @@ fn sustained_traffic_from_one_process() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -625,7 +625,7 @@ fn sustained_traffic_from_multiple_processes() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "1.1.1.1",
             "10.0.0.2",
@@ -655,7 +655,7 @@ fn sustained_traffic_from_multiple_processes() {
             443,
             b"I come 3.3.3.3 one second later",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -668,7 +668,7 @@ fn sustained_traffic_from_multiple_processes() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
@@ -682,7 +682,7 @@ fn sustained_traffic_from_multiple_processes() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -692,7 +692,7 @@ fn sustained_traffic_from_multiple_processes() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -710,7 +710,7 @@ fn sustained_traffic_from_multiple_processes_bi_directional() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "10.0.0.2",
             "3.3.3.3",
@@ -768,7 +768,7 @@ fn sustained_traffic_from_multiple_processes_bi_directional() {
             12345,
             b"10.0.0.2 forever!",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -781,7 +781,7 @@ fn sustained_traffic_from_multiple_processes_bi_directional() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
@@ -795,7 +795,7 @@ fn sustained_traffic_from_multiple_processes_bi_directional() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -805,7 +805,7 @@ fn sustained_traffic_from_multiple_processes_bi_directional() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -823,7 +823,7 @@ fn traffic_with_host_names() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "10.0.0.2",
             "3.3.3.3",
@@ -881,7 +881,7 @@ fn traffic_with_host_names() {
             12345,
             b"10.0.0.2 forever!",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -894,7 +894,7 @@ fn traffic_with_host_names() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let mut ips_to_hostnames = HashMap::new();
     ips_to_hostnames.insert(
         IpAddr::V4("1.1.1.1".parse().unwrap()),
@@ -921,7 +921,7 @@ fn traffic_with_host_names() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -931,7 +931,7 @@ fn traffic_with_host_names() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: false,
     };
@@ -949,7 +949,7 @@ fn no_resolve_mode() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         Some(build_tcp_packet(
             "10.0.0.2",
             "3.3.3.3",
@@ -1007,7 +1007,7 @@ fn no_resolve_mode() {
             12345,
             b"10.0.0.2 forever!",
         )),
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -1020,7 +1020,7 @@ fn no_resolve_mode() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let mut ips_to_hostnames = HashMap::new();
     ips_to_hostnames.insert(
         IpAddr::V4("1.1.1.1".parse().unwrap()),
@@ -1047,7 +1047,7 @@ fn no_resolve_mode() {
     });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -1057,7 +1057,7 @@ fn no_resolve_mode() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: true,
         no_resolve: true,
     };
diff --git a/src/tests/cases/ui.rs b/src/tests/cases/ui.rs
index f2f5374..78f4f73 100644
--- a/src/tests/cases/ui.rs
+++ b/src/tests/cases/ui.rs
@@ -1,6 +1,6 @@
 use crate::tests::fakes::TerminalEvent::*;
 use crate::tests::fakes::{
-    create_fake_dns_client, create_fake_on_winch, get_interface, get_open_sockets, KeyboardEvents,
+    create_fake_dns_client, create_fake_on_winch, get_interfaces, get_open_sockets, KeyboardEvents,
     NetworkFrames, TestBackend,
 };
 
@@ -55,9 +55,9 @@ fn basic_startup() {
         None, // sleep
         Some(Event::Key(Key::Ctrl('c'))),
     ]));
-    let network_frames = NetworkFrames::new(vec![
+    let network_frames = vec![NetworkFrames::new(vec![
         None, // sleep
-    ]);
+    ])];
 
     let terminal_width = Arc::new(Mutex::new(190));
     let terminal_height = Arc::new(Mutex::new(50));
@@ -70,14 +70,14 @@ fn basic_startup() {
         terminal_width,
         terminal_height,
     );
-    let network_interface = get_interface();
+    let network_interfaces = get_interfaces();
     let dns_client = create_fake_dns_client(HashMap::new());
     let on_winch = create_fake_on_winch(false);
     let cleanup = Box::new(|| {});
     let write_to_stdout = Box::new({ move |_output: String| {} });
 
     let os_input = OsInputOutput {
-        network_interface,
+        network_interfaces,
         network_frames,
         get_open_sockets,
         keyboard_events,
@@ -87,7 +87,7 @@ fn basic_startup() {
         write_to_stdout,
     };
     let opts = Opt {
-        interface: String::from("interface_name"),
+        interface: Some(String::from("interface_name")),
         raw: false,
         no_