tetragon: Add LoadMultiUprobeProgram function

Adding LoadMultiUprobeProgram function to load uprobe multi programs. Signed-off-by: Jiri Olsa <[email protected]>
cilium · Dec 25, 2023 · 85349d6 · 85349d6
1 parent 29f9625
commit 85349d6
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Showing 2 changed files with 64 additions and 0 deletions.
diff --git a/pkg/sensors/program/loader.go b/pkg/sensors/program/loader.go
@@ -303,6 +303,51 @@ func UprobeAttach(load *Program) AttachFunc {
 	}
 }
 
+func MultiUprobeAttach(load *Program) AttachFunc {
+	return func(coll *ebpf.Collection, collSpec *ebpf.CollectionSpec,
+		prog *ebpf.Program, spec *ebpf.ProgramSpec) (unloader.Unloader, error) {
+
+		data, ok := load.AttachData.(*MultiUprobeAttachData)
+		if !ok {
+			return nil, fmt.Errorf("attaching '%s' failed: wrong attach data", spec.Name)
+		}
+
+		linkFn := func() ([]link.Link, error) {
+			var links []link.Link
+			var lnk link.Link
+
+			for path, attach := range data.Attach {
+				exec, err := link.OpenExecutable(path)
+				if err != nil {
+					return nil, err
+				}
+				lnk, err = exec.UprobeMulti(attach.Symbols, prog, &link.UprobeMultiOptions{Cookies: attach.Cookies})
+				if err != nil {
+					return nil, err
+				}
+				links = append(links, lnk)
+			}
+			return links, nil
+		}
+
+		links, err := linkFn()
+		if err != nil {
+			return nil, fmt.Errorf("attaching '%s' failed: %w", spec.Name, err)
+		}
+
+		return &unloader.MultiRelinkUnloader{
+			UnloadProg: unloader.ChainUnloader{
+				unloader.PinUnloader{
+					Prog: prog,
+				},
+			}.Unload,
+			IsLinked: true,
+			Links:    links,
+			RelinkFn: linkFn,
+		}, nil
+	}
+}
+
 func NoAttach() AttachFunc {
 	return func(coll *ebpf.Collection, collSpec *ebpf.CollectionSpec,
 		prog *ebpf.Program, spec *ebpf.ProgramSpec) (unloader.Unloader, error) {
@@ -542,6 +587,15 @@ func LoadLSMProgram(bpfDir, mapDir string, load *Program, verbose int) error {
 	return loadProgram(bpfDir, []string{mapDir}, load, opts, verbose)
 }
 
+func LoadMultiUprobeProgram(bpfDir, mapDir string, load *Program, verbose int) error {
+	ci := &customInstall{fmt.Sprintf("%s-up_calls", load.PinPath), "uprobe"}
+	opts := &loadOpts{
+		attach: MultiUprobeAttach(load),
+		ci:     ci,
+	}
+	return loadProgram(bpfDir, []string{mapDir}, load, opts, verbose)
+}
+
 func slimVerifierError(errStr string) string {
 	// The error is potentially up to 'verifierLogBufferSize' bytes long,
 	// and most of it is not interesting. For a user-friendly output, we'll

diff --git a/pkg/sensors/program/program.go b/pkg/sensors/program/program.go
@@ -54,6 +54,16 @@ type UprobeAttachData struct {
 	Symbol string
 }
 
+type MultiUprobeAttachSymbolsCookies struct {
+	Symbols []string
+	Cookies []uint64
+}
+
+type MultiUprobeAttachData struct {
+	// Path -> []{Symbol,Cookie}
+	Attach map[string]*MultiUprobeAttachSymbolsCookies
+}
+
 // Program reprents a BPF program.
 type Program struct {
 	// Name is the name of the BPF object file.