Pause and resume packet captures

CHANGELOG.md

@@ -4,6 +4,7 @@ All Sniffnet releases with the relative changes are documented in this file.
 
 ## [UNRELEASED]
 - Send remote notifications via webhook ([#991](https://github.com/GyulyVGC/sniffnet/pull/991) — fixes [#841](https://github.com/GyulyVGC/sniffnet/issues/841))
+- Pause and resume packet captures ([#992](https://github.com/GyulyVGC/sniffnet/pull/992) — fixes [#551](https://github.com/GyulyVGC/sniffnet/issues/551))
 - Added Czech translation 🇨🇿 ([#960](https://github.com/GyulyVGC/sniffnet/pull/960))
 - Improve update checks using `semver` ([#891](https://github.com/GyulyVGC/sniffnet/pull/891))
 - Build the app also for Windows ARM64 (fixes [#988](https://github.com/GyulyVGC/sniffnet/issues/988))

src/gui/components/header.rs

@@ -15,6 +15,7 @@ use crate::gui::types::message::Message;
 use crate::gui::types::settings::Settings;
 use crate::translations::translations::{quit_analysis_translation, settings_translation};
 use crate::translations::translations_3::thumbnail_mode_translation;
+use crate::translations::translations_4::{pause_translation, resume_translation};
 use crate::utils::types::icon::Icon;
 use crate::{Language, SNIFFNET_TITLECASE, StyleType};
 
@@ -37,6 +38,7 @@ pub fn header(sniffer: &Sniffer) -> Container<'_, Message, StyleType> {
             language,
             color_gradient,
             unread_notifications,
+            sniffer.frozen,
         );
     }
 
@@ -60,10 +62,15 @@ pub fn header(sniffer: &Sniffer) -> Container<'_, Message, StyleType> {
                 Container::new(Space::with_width(60))
             })
             .push(horizontal_space())
-            .push(Container::new(Space::with_width(40)))
+            .push(Container::new(Space::with_width(80)))
             .push(Space::with_width(20))
             .push(logo)
             .push(Space::with_width(20))
+            .push(if is_running {
+                Container::new(get_button_freeze(font, language, sniffer.frozen, false))
+            } else {
+                Container::new(Space::with_width(40))
+            })
             .push(if is_running {
                 Container::new(get_button_minimize(font, language, false))
             } else {
@@ -161,9 +168,56 @@ pub fn get_button_minimize<'a>(
     .class(ButtonType::Thumbnail)
     .on_press(Message::ToggleThumbnail(false));
 
-    Tooltip::new(content, Text::new(tooltip).font(font), Position::Right)
-        .gap(0)
-        .class(tooltip_style)
+    Tooltip::new(
+        content,
+        Text::new(tooltip).font(font),
+        Position::FollowCursor,
+    )
+    .gap(0)
+    .class(tooltip_style)
+}
+
+pub fn get_button_freeze<'a>(
+    font: Font,
+    language: Language,
+    frozen: bool,
+    thumbnail: bool,
+) -> Tooltip<'a, Message, StyleType> {
+    let size = if thumbnail { 19 } else { 23 };
+    let button_size = if thumbnail { 30 } else { 40 };
+    let icon = if frozen { Icon::Resume } else { Icon::Pause };
+    let tooltip = if thumbnail {
+        ""
+    } else if frozen {
+        resume_translation(language)
+    } else {
+        pause_translation(language)
+    };
+    let tooltip_style = if thumbnail {
+        ContainerType::Standard
+    } else {
+        ContainerType::Tooltip
+    };
+
+    let content = button(
+        icon.to_text()
+            .size(size)
+            .align_x(Alignment::Center)
+            .align_y(Alignment::Center),
+    )
+    .padding(0)
+    .height(button_size)
+    .width(button_size)
+    .class(ButtonType::Thumbnail)
+    .on_press(Message::Freeze);
+
+    Tooltip::new(
+        content,
+        Text::new(tooltip).font(font),
+        Position::FollowCursor,
+    )
+    .gap(0)
+    .class(tooltip_style)
 }
 
 fn thumbnail_header<'a>(
@@ -172,14 +226,16 @@ fn thumbnail_header<'a>(
     language: Language,
     color_gradient: GradientType,
     unread_notifications: usize,
+    frozen: bool,
 ) -> Container<'a, Message, StyleType> {
     Container::new(
         Row::new()
             .align_y(Alignment::Center)
             .push(horizontal_space())
-            .push(Space::with_width(80))
+            .push(Space::with_width(110))
             .push(Text::new(SNIFFNET_TITLECASE).font(font_headers))
             .push(Space::with_width(10))
+            .push(get_button_freeze(font, language, frozen, true))
             .push(get_button_minimize(font, language, true))
             .push(horizontal_space())
             .push(if unread_notifications > 0 {

src/gui/sniffer.rs

@@ -121,6 +121,10 @@ pub struct Sniffer {
     pub id: Option<Id>,
     /// Host data for filter dropdowns (comboboxes)
     pub host_data_states: HostDataStates,
+    /// Flag reporting whether the packet capture is frozen
+    pub frozen: bool,
+    /// Sender to freeze the packet capture
+    freeze_tx: Option<tokio::sync::broadcast::Sender<()>>,
 }
 
 impl Sniffer {
@@ -160,6 +164,8 @@ impl Sniffer {
             thumbnail: false,
             id: None,
             host_data_states: HostDataStates::default(),
+            frozen: false,
+            freeze_tx: None,
         }
     }
 
@@ -175,6 +181,7 @@ impl Sniffer {
                 }) => match key.as_ref() {
                     Key::Character("q") => Some(Message::QuitWrapper),
                     Key::Character("t") => Some(Message::CtrlTPressed),
+                    Key::Named(Named::Space) => Some(Message::CtrlSpacePressed),
                     _ => None,
                 },
                 _ => None,
@@ -185,6 +192,7 @@ impl Sniffer {
                     Modifiers::COMMAND => match key.as_ref() {
                         Key::Character("q") => Some(Message::QuitWrapper),
                         Key::Character("t") => Some(Message::CtrlTPressed),
+                        Key::Named(Named::Space) => Some(Message::CtrlSpacePressed),
                         Key::Character(",") => Some(Message::OpenLastSettings),
                         Key::Named(Named::Backspace) => Some(Message::ResetButtonPressed),
                         Key::Character("d") => Some(Message::CtrlDPressed),
@@ -500,6 +508,14 @@ impl Sniffer {
                     return Task::done(Message::ToggleThumbnail(false));
                 }
             }
+            Message::CtrlSpacePressed => {
+                if self.running_page.is_some()
+                    && self.settings_page.is_none()
+                    && self.modal.is_none()
+                {
+                    return Task::done(Message::Freeze);
+                }
+            }
             Message::ScaleFactorShortcut(increase) => {
                 let scale_factor = self.conf.settings.scale_factor;
                 if !(scale_factor > 2.99 && increase || scale_factor < 0.31 && !increase) {
@@ -555,6 +571,12 @@ impl Sniffer {
                     .remote_notifications
                     .set_url(&url);
             }
+            Message::Freeze => {
+                self.frozen = !self.frozen;
+                if let Some(tx) = &self.freeze_tx {
+                    let _ = tx.send(());
+                }
+            }
         }
         Task::none()
     }
@@ -750,6 +772,9 @@ impl Sniffer {
             self.traffic_chart
                 .change_capture_source(matches!(capture_source, CaptureSource::Device(_)));
             let (tx, rx) = async_channel::unbounded();
+            let (freeze_tx, freeze_rx) = tokio::sync::broadcast::channel(1_048_575);
+            let freeze_rx2 = freeze_tx.subscribe();
+            let filters = self.conf.filters.clone();
             let _ = thread::Builder::new()
                 .name("thread_parse_packets".to_string())
                 .spawn(move || {
@@ -758,11 +783,14 @@ impl Sniffer {
                         capture_source,
                         &mmdb_readers,
                         capture_context,
+                        filters,
                         &tx,
+                        (freeze_rx, freeze_rx2),
                     );
                 })
                 .log_err(location!());
             self.current_capture_rx.1 = Some(rx.clone());
+            self.freeze_tx = Some(freeze_tx);
             return Task::run(rx, |backend_msg| match backend_msg {
                 BackendTrafficMessage::TickRun(cap_id, msg, host_msg, no_more_packets) => {
                     Message::TickRun(cap_id, msg, host_msg, no_more_packets)
@@ -800,6 +828,8 @@ impl Sniffer {
         self.page_number = 1;
         self.thumbnail = false;
         self.host_data_states = HostDataStates::default();
+        self.frozen = false;
+        self.freeze_tx = None;
     }
 
     fn set_device(&mut self, name: &str) {

src/gui/types/message.rs

@@ -121,6 +121,8 @@ pub enum Message {
     Drag,
     /// Ctrl+T keys have been pressed
     CtrlTPressed,
+    /// Ctrl+Space keys have been pressed
+    CtrlSpacePressed,
     /// Edit scale factor via keyboard shortcut
     ScaleFactorShortcut(bool),
     /// Set new release status
@@ -139,4 +141,6 @@ pub enum Message {
     ToggleRemoteNotifications,
     /// The remote notifications URL has been updated
     RemoteNotificationsUrl(String),
+    /// Pause or resume live capture
+    Freeze,
 }

src/networking/parse_packets.rs

@@ -1,5 +1,6 @@
 //! Module containing functions executed by the thread in charge of parsing sniffed packets
 
+use crate::gui::types::filters::Filters;
 use crate::location;
 use crate::mmdb::asn::get_asn;
 use crate::mmdb::country::get_country;
@@ -32,15 +33,20 @@ use std::net::IpAddr;
 use std::sync::{Arc, Mutex};
 use std::thread;
 use std::time::{Duration, Instant};
+use tokio::sync::broadcast::Receiver;
 
 /// The calling thread enters a loop in which it waits for network packets
 pub fn parse_packets(
     cap_id: usize,
     mut cs: CaptureSource,
     mmdb_readers: &MmdbReaders,
     capture_context: CaptureContext,
+    filters: Filters,
     tx: &Sender<BackendTrafficMessage>,
+    freeze_rxs: (Receiver<()>, Receiver<()>),
 ) {
+    let (mut freeze_rx, mut freeze_rx_2) = freeze_rxs;
+
     let my_link_type = capture_context.my_link_type();
     let (cap, mut savefile) = capture_context.consume();
 
@@ -55,10 +61,18 @@ pub fn parse_packets(
     let (pcap_tx, pcap_rx) = std::sync::mpsc::sync_channel(10_000);
     let _ = thread::Builder::new()
         .name("thread_packet_stream".to_string())
-        .spawn(move || packet_stream(cap, &pcap_tx))
+        .spawn(move || packet_stream(cap, &pcap_tx, &mut freeze_rx_2, &filters))
         .log_err(location!());
 
     loop {
+        // check if we need to freeze the parsing
+        if freeze_rx.try_recv().is_ok() {
+            // wait until unfreeze
+            let _ = freeze_rx.blocking_recv();
+            // reset the first packet ticks
+            first_packet_ticks = Some(Instant::now());
+        }
+
         let (packet_res, cap_stats) = pcap_rx
             .recv_timeout(Duration::from_millis(150))
             .unwrap_or((Err(pcap::Error::TimeoutExpired), None));
@@ -486,8 +500,20 @@ fn maybe_send_tick_run_offline(
 fn packet_stream(
     mut cap: CaptureType,
     tx: &std::sync::mpsc::SyncSender<(Result<PacketOwned, pcap::Error>, Option<pcap::Stat>)>,
+    freeze_rx: &mut Receiver<()>,
+    filters: &Filters,
 ) {
     loop {
+        // check if we need to freeze the parsing
+        if freeze_rx.try_recv().is_ok() {
+            // pause the capture
+            cap.pause();
+            // wait until unfreeze
+            let _ = freeze_rx.blocking_recv();
+            // resume the capture
+            cap.resume(filters);
+        }
+
         let packet_res = cap.next_packet();
         let packet_owned = packet_res.map(|p| PacketOwned {
             header: *p.header,

src/networking/types/capture_context.rs

@@ -128,7 +128,7 @@ impl CaptureType {
             CaptureSource::Device(device) => {
                 let inactive = Capture::from_device(device.to_pcap_device())?;
                 let cap = inactive
-                    .promisc(true)
+                    .promisc(false)
                     .buffer_size(2_000_000) // 2MB buffer -> 10k packets of 200 bytes
                     .snaplen(if pcap_out_path.is_some() {
                         i32::from(u16::MAX)
@@ -150,6 +150,22 @@ impl CaptureType {
             Self::Offline(cap) => cap.filter(bpf, true),
         }
     }
+
+    pub fn pause(&mut self) {
+        if let Self::Live(cap) = self {
+            let _ = cap.filter("less 2", true).log_err(location!());
+        }
+    }
+
+    pub fn resume(&mut self, filters: &Filters) {
+        if let Self::Live(cap) = self {
+            if filters.is_some_filter_active() {
+                let _ = cap.filter(filters.bpf(), true).log_err(location!());
+            } else if cap.filter("", true).log_err(location!()).is_err() {
+                let _ = cap.filter("greater 0", true).log_err(location!());
+            }
+        }
+    }
 }
 
 #[derive(Clone)]

src/utils/types/icon.rs

@@ -52,6 +52,8 @@ pub enum Icon {
     Update,
     Warning,
     Waves,
+    Pause,
+    Resume,
 }
 
 impl Icon {
@@ -105,6 +107,8 @@ impl Icon {
             Icon::Update => '<',
             // Icon::Expand => 'p',
             // Icon::Collapse => 'q',
+            Icon::Pause => '-',
+            Icon::Resume => '+',
         }
     }