Feat restrict flows

CHANGELOG.md

@@ -26,6 +26,7 @@ to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 - Ensure `paris` and `dublin` ECMP strategy are only used with supported
   protocols ([#848](https://github.com/fujiapple852/trippy/issues/848))
+- Restrict flows to `paris` and `dublin` ECMP strategies ([#1007](https://github.com/fujiapple852/trippy/issues/1007))
 - Improved Tui table column layout logic ([#925](https://github.com/fujiapple852/trippy/issues/925))
 - Use exclusive reference `&mut` for all Socket operations ([#843](https://github.com/fujiapple852/trippy/issues/843))
 

src/backend.rs

@@ -19,11 +19,16 @@ pub struct Backend {
 
 impl Backend {
     /// Create a tracing `Backend`.
-    pub fn new(tracer_config: Config, channel_config: ChannelConfig, max_samples: usize) -> Self {
+    pub fn new(
+        tracer_config: Config,
+        channel_config: ChannelConfig,
+        max_samples: usize,
+        max_flows: usize,
+    ) -> Self {
         Self {
             tracer_config,
             channel_config,
-            trace: Arc::new(RwLock::new(Trace::new(max_samples))),
+            trace: Arc::new(RwLock::new(Trace::new(max_samples, max_flows))),
         }
     }
 

src/backend/trace.rs

@@ -10,7 +10,16 @@ use trippy::tracing::{Extensions, ProbeState, Round, TimeToLive, TracerRound};
 /// The state of all hops in a trace.
 #[derive(Debug, Clone)]
 pub struct Trace {
+    /// The maximum number of samples to record per hop.
+    ///
+    /// Once the maximum number of samples has been reached the oldest sample
+    /// is discarded (FIFO).
     max_samples: usize,
+    /// The maximum number of flows to record.
+    ///
+    /// Once the maximum number of flows has been reached no new flows will be
+    /// created, existing flows are updated and are never removed.
+    max_flows: usize,
     /// The flow id for the current round.
     round_flow_id: FlowId,
     /// Tracing data per registered flow id.
@@ -23,12 +32,13 @@ pub struct Trace {
 
 impl Trace {
     /// Create a new `Trace`.
-    pub fn new(max_samples: usize) -> Self {
+    pub fn new(max_samples: usize, max_flows: usize) -> Self {
         Self {
             trace_data: once((Self::default_flow_id(), TraceData::new(max_samples)))
                 .collect::<HashMap<FlowId, TraceData>>(),
             round_flow_id: Self::default_flow_id(),
             max_samples,
+            max_flows,
             registry: FlowRegistry::new(),
             error: None,
         }
@@ -105,10 +115,12 @@ impl Trace {
                 })
                 .take(usize::from(round.largest_ttl.0)),
         );
-        let flow_id = self.registry.register(flow);
-        self.round_flow_id = flow_id;
         self.update_trace_flow(Self::default_flow_id(), round);
-        self.update_trace_flow(flow_id, round);
+        if self.registry.flows().len() < self.max_flows {
+            let flow_id = self.registry.register(flow);
+            self.round_flow_id = flow_id;
+            self.update_trace_flow(flow_id, round);
+        }
     }
 
     fn update_trace_flow(&mut self, flow_id: FlowId, round: &TracerRound<'_>) {

src/config.rs

@@ -36,17 +36,17 @@ pub enum Mode {
     Tui,
     /// Display a continuous stream of tracing data
     Stream,
-    /// Generate an pretty text table report for N cycles.
+    /// Generate a pretty text table report for N cycles.
     Pretty,
-    /// Generate a markdown text table report for N cycles.
+    /// Generate a Markdown text table report for N cycles.
     Markdown,
     /// Generate a CSV report for N cycles.
     Csv,
     /// Generate a JSON report for N cycles.
     Json,
     /// Generate a Graphviz DOT file for N cycles.
     Dot,
-    /// Display all flows.
+    /// Display all flows for N cycles.
     Flows,
     /// Do not generate any tracing output for N cycles.
     Silent,
@@ -334,6 +334,16 @@ impl TrippyConfig {
         Self::build_config(args, cfg_file, platform)
     }
 
+    /// The maximum number of flows allowed.
+    ///
+    /// This is restricted to 1 for the classic strategy.
+    pub fn max_flows(&self) -> usize {
+        match self.multipath_strategy {
+            MultipathStrategy::Classic => 1,
+            _ => self.tui_max_flows,
+        }
+    }
+
     #[allow(clippy::too_many_lines)]
     fn build_config(args: Args, cfg_file: ConfigFile, platform: &Platform) -> anyhow::Result<Self> {
         let &Platform {
@@ -641,6 +651,7 @@ impl TrippyConfig {
         validate_strategy(multipath_strategy, unprivileged)?;
         validate_protocol_strategy(protocol, multipath_strategy)?;
         validate_multi(mode, protocol, &args.targets, dns_resolve_all)?;
+        validate_flows(mode, multipath_strategy)?;
         validate_ttl(first_ttl, max_ttl)?;
         validate_max_inflight(max_inflight)?;
         validate_read_timeout(read_timeout)?;
@@ -918,6 +929,17 @@ fn validate_multi(
     }
 }
 
+/// Validate that flows and dot mode are only used with paris or dublin
+/// multipath strategy.
+fn validate_flows(mode: Mode, strategy: MultipathStrategy) -> anyhow::Result<()> {
+    match (mode, strategy) {
+        (Mode::Flows | Mode::Dot, MultipathStrategy::Classic) => Err(anyhow!(
+            "this mode requires the paris or dublin multipath strategy"
+        )),
+        _ => Ok(()),
+    }
+}
+
 /// Validate `first_ttl` and `max_ttl`.
 fn validate_ttl(first_ttl: u8, max_ttl: u8) -> anyhow::Result<()> {
     if (first_ttl as usize) < 1 || (first_ttl as usize) > MAX_HOPS {
@@ -1150,11 +1172,13 @@ mod tests {
     #[test_case("trip example.com --mode markdown", Ok(cfg().mode(Mode::Markdown).max_rounds(Some(10)).build()); "markdown mode")]
     #[test_case("trip example.com --mode csv", Ok(cfg().mode(Mode::Csv).max_rounds(Some(10)).build()); "csv mode")]
     #[test_case("trip example.com --mode json", Ok(cfg().mode(Mode::Json).max_rounds(Some(10)).build()); "json mode")]
-    #[test_case("trip example.com --mode dot", Ok(cfg().mode(Mode::Dot).max_rounds(Some(10)).build()); "dot mode")]
-    #[test_case("trip example.com --mode flows", Ok(cfg().mode(Mode::Flows).max_rounds(Some(10)).build()); "flows mode")]
+    #[test_case("trip example.com --mode dot --udp -R paris", Ok(cfg().mode(Mode::Dot).max_rounds(Some(10)).multipath_strategy(MultipathStrategy::Paris).protocol(Protocol::Udp).port_direction(PortDirection::FixedSrc(Port(1024))).build()); "dot mode")]
+    #[test_case("trip example.com --mode flows --udp -R paris", Ok(cfg().mode(Mode::Flows).max_rounds(Some(10)).multipath_strategy(MultipathStrategy::Paris).protocol(Protocol::Udp).port_direction(PortDirection::FixedSrc(Port(1024))).build()); "flows mode")]
     #[test_case("trip example.com --mode silent", Ok(cfg().mode(Mode::Silent).max_rounds(Some(10)).build()); "silent mode")]
     #[test_case("trip example.com -m tui", Ok(cfg().mode(Mode::Tui).build()); "tui mode short")]
     #[test_case("trip example.com --mode foo", Err(anyhow!(format!("error: one of the values isn't valid for an argument"))); "invalid mode")]
+    #[test_case("trip example.com --mode dot", Err(anyhow!(format!("this mode requires the paris or dublin multipath strategy"))); "invalid dot mode")]
+    #[test_case("trip example.com --mode flows", Err(anyhow!(format!("this mode requires the paris or dublin multipath strategy"))); "invalid flows mode")]
     fn test_mode(cmd: &str, expected: anyhow::Result<TrippyConfig>) {
         compare(parse_config(cmd), expected);
     }

src/frontend/render/header.rs

@@ -85,10 +85,23 @@ pub fn render(f: &mut Frame<'_>, app: &TuiApp, rect: Rect) {
     let source = render_source(app);
     let dest = render_destination(app);
     let target = format!("{source} -> {dest}");
-    let plural_flows = if app.tracer_data().flows().len() > 1 {
-        "flows"
+    let discovered = if app.tui_config.max_flows > 1 {
+        let plural_flows = if app.tracer_data().flows().len() > 1 {
+            "flows"
+        } else {
+            "flow"
+        };
+        format!(
+            ", discovered {} hops and {} unique {}",
+            app.tracer_data().hops(app.selected_flow).len(),
+            app.tracer_data().flows().len(),
+            plural_flows
+        )
     } else {
-        "flow"
+        format!(
+            ", discovered {} hops",
+            app.tracer_data().hops(app.selected_flow).len()
+        )
     };
     let left_line = vec![
         Line::from(vec![
@@ -104,12 +117,7 @@ pub fn render(f: &mut Frame<'_>, app: &TuiApp, rect: Rect) {
         Line::from(vec![
             Span::styled("Status: ", Style::default().add_modifier(Modifier::BOLD)),
             Span::raw(render_status(app)),
-            Span::raw(format!(
-                ", discovered {} hops and {} unique {}",
-                app.tracer_data().hops(app.selected_flow).len(),
-                app.tracer_data().flows().len(),
-                plural_flows
-            )),
+            Span::raw(discovered),
         ]),
     ];
 

src/frontend/tui_app.rs

@@ -54,7 +54,7 @@ impl TuiApp {
         trace_info: Vec<TraceInfo>,
     ) -> Self {
         Self {
-            selected_tracer_data: Trace::new(tui_config.max_samples),
+            selected_tracer_data: Trace::new(tui_config.max_samples, tui_config.max_flows),
             trace_info,
             tui_config,
             table_state: TableState::default(),
@@ -88,7 +88,7 @@ impl TuiApp {
 
     pub fn clear_trace_data(&mut self) {
         *self.trace_info[self.trace_selected].data.write() =
-            Trace::new(self.tui_config.max_samples);
+            Trace::new(self.tui_config.max_samples, self.tui_config.max_flows);
     }
 
     pub fn selected_hop_or_target(&self) -> &Hop {
@@ -323,7 +323,7 @@ impl TuiApp {
     }
 
     pub fn toggle_flows(&mut self) {
-        if self.trace_info.len() == 1 {
+        if self.trace_info.len() == 1 && self.tui_config.max_flows > 1 {
             if self.show_flows {
                 self.selected_flow = FlowId(0);
                 self.show_flows = false;

src/main.rs

@@ -214,7 +214,12 @@ fn start_tracer(
     };
     let channel_config = make_channel_config(cfg, source_addr, target_addr);
     let tracer_config = make_tracer_config(cfg, target_addr, trace_identifier)?;
-    let backend = Backend::new(tracer_config, channel_config, cfg.tui_max_samples);
+    let backend = Backend::new(
+        tracer_config,
+        channel_config,
+        cfg.tui_max_samples,
+        cfg.max_flows(),
+    );
     let trace_data = backend.trace();
     thread::Builder::new()
         .name(format!("tracer-{}", tracer_config.trace_identifier.0))
@@ -339,7 +344,7 @@ fn make_tui_config(args: &TrippyConfig) -> TuiConfig {
         args.tui_geoip_mode,
         args.tui_max_addrs,
         args.tui_max_samples,
-        args.tui_max_flows,
+        args.max_flows(),
         args.tui_theme,
         &args.tui_bindings,
         &args.tui_custom_columns,

test_resources/completions_fish.txt

@@ -1,5 +1,5 @@
 complete -c trip -s c -l config-file -d 'Config file' -r -F
-complete -c trip -s m -l mode -d 'Output mode [default: tui]' -r -f -a "{tui	'Display interactive TUI',stream	'Display a continuous stream of tracing data',pretty	'Generate an pretty text table report for N cycles',markdown	'Generate a markdown text table report for N cycles',csv	'Generate a CSV report for N cycles',json	'Generate a JSON report for N cycles',dot	'Generate a Graphviz DOT file for N cycles',flows	'Display all flows',silent	'Do not generate any tracing output for N cycles'}"
+complete -c trip -s m -l mode -d 'Output mode [default: tui]' -r -f -a "{tui	'Display interactive TUI',stream	'Display a continuous stream of tracing data',pretty	'Generate a pretty text table report for N cycles',markdown	'Generate a Markdown text table report for N cycles',csv	'Generate a CSV report for N cycles',json	'Generate a JSON report for N cycles',dot	'Generate a Graphviz DOT file for N cycles',flows	'Display all flows for N cycles',silent	'Do not generate any tracing output for N cycles'}"
 complete -c trip -s p -l protocol -d 'Tracing protocol [default: icmp]' -r -f -a "{icmp	'Internet Control Message Protocol',udp	'User Datagram Protocol',tcp	'Transmission Control Protocol'}"
 complete -c trip -s F -l addr-family -d 'The address family [default: Ipv4thenIpv6]' -r -f -a "{ipv4	'Ipv4 only',ipv6	'Ipv6 only',ipv6-then-ipv4	'Ipv6 with a fallback to Ipv4',ipv4-then-ipv6	'Ipv4 with a fallback to Ipv6'}"
 complete -c trip -s P -l target-port -d 'The target port (TCP & UDP only) [default: 80]' -r

test_resources/completions_zsh.txt

@@ -19,21 +19,21 @@ _trip() {
 '--config-file=[Config file]:CONFIG_FILE:_files' \
 '-m+[Output mode \[default\: tui\]]:MODE:((tui\:"Display interactive TUI"
 stream\:"Display a continuous stream of tracing data"
-pretty\:"Generate an pretty text table report for N cycles"
-markdown\:"Generate a markdown text table report for N cycles"
+pretty\:"Generate a pretty text table report for N cycles"
+markdown\:"Generate a Markdown text table report for N cycles"
 csv\:"Generate a CSV report for N cycles"
 json\:"Generate a JSON report for N cycles"
 dot\:"Generate a Graphviz DOT file for N cycles"
-flows\:"Display all flows"
+flows\:"Display all flows for N cycles"
 silent\:"Do not generate any tracing output for N cycles"))' \
 '--mode=[Output mode \[default\: tui\]]:MODE:((tui\:"Display interactive TUI"
 stream\:"Display a continuous stream of tracing data"
-pretty\:"Generate an pretty text table report for N cycles"
-markdown\:"Generate a markdown text table report for N cycles"
+pretty\:"Generate a pretty text table report for N cycles"
+markdown\:"Generate a Markdown text table report for N cycles"
 csv\:"Generate a CSV report for N cycles"
 json\:"Generate a JSON report for N cycles"
 dot\:"Generate a Graphviz DOT file for N cycles"
-flows\:"Display all flows"
+flows\:"Display all flows for N cycles"
 silent\:"Do not generate any tracing output for N cycles"))' \
 '-p+[Tracing protocol \[default\: icmp\]]:PROTOCOL:((icmp\:"Internet Control Message Protocol"
 udp\:"User Datagram Protocol"

test_resources/usage_long.txt

@@ -16,12 +16,12 @@ Options:
           Possible values:
           - tui:      Display interactive TUI
           - stream:   Display a continuous stream of tracing data
-          - pretty:   Generate an pretty text table report for N cycles
-          - markdown: Generate a markdown text table report for N cycles
+          - pretty:   Generate a pretty text table report for N cycles
+          - markdown: Generate a Markdown text table report for N cycles
           - csv:      Generate a CSV report for N cycles
           - json:     Generate a JSON report for N cycles
           - dot:      Generate a Graphviz DOT file for N cycles
-          - flows:    Display all flows
+          - flows:    Display all flows for N cycles
           - silent:   Do not generate any tracing output for N cycles
 
   -u, --unprivileged

trippy-config-sample.toml

@@ -25,13 +25,16 @@
 # Allowed values are:
 #   tui         - Display interactive Tui [default]
 #   stream      - Display a continuous stream of tracing data
-#   pretty      - Generate an pretty text table report for N cycles
-#   markdown    - Generate a markdown text table report for N cycles
+#   pretty      - Generate a pretty text table report for N cycles
+#   markdown    - Generate a Markdown text table report for N cycles
 #   csv         - Generate a CSV report for N cycles
 #   json        - Generate a JSON report for N cycles
 #   dot         - Generate a Graphviz DOT report for N cycles
-#   flows       - Display all flows
+#   flows       - Display all flows for N cycles
 #   silent      - Do not generate any output for N cycles
+#
+# Note: the dot and flows modes are only allowed with paris or dublin
+# multipath strategy.
 mode = "tui"
 
 # Trace without requiring elevated privileges [default: false]
@@ -306,7 +309,7 @@ tui-max-addrs = 0
 # The maximum number of samples to record per hop [default: 256]
 tui-max-samples = 256
 
-# The maximum number of flows to show [default: 40]
+# The maximum number of flows to show [default: 64]
 tui-max-flows = 64
 
 # Whether to preserve the screen on exit [default: false]