From 4e8d760a12f8caf124c1cea75ff319c548fb885d Mon Sep 17 00:00:00 2001
From: "M. Mert Yildiran" <mehmet@up9.com>
Date: Wed, 1 Jun 2022 17:30:29 +0300
Subject: [PATCH] Add `MIZU_GLOBAL_GOLANG_PATH` environment variable

---
 tap/passive_tapper.go       |  9 +++++++++
 tap/tlstapper/tls_tapper.go | 16 ++++++++++++++++
 2 files changed, 25 insertions(+)

diff --git a/tap/passive_tapper.go b/tap/passive_tapper.go
index 3c7dd8ee4..3fa88ff33 100644
--- a/tap/passive_tapper.go
+++ b/tap/passive_tapper.go
@@ -293,6 +293,15 @@ func startTlsTapper(extension *api.Extension, outputItems chan *api.OutputChanne
 		}
 	}
 
+	// A quick way to instrument Go `crypto/tls` using executable path - used for debuging and troubleshooting
+	//
+	if os.Getenv("MIZU_GLOBAL_GOLANG_PATH") != "" {
+		if err := tls.GlobalGolangTapPath(os.Getenv("MIZU_GLOBAL_GOLANG_PATH")); err != nil {
+			tlstapper.LogError(err)
+			return nil
+		}
+	}
+
 	var emitter api.Emitter = &api.Emitting{
 		AppStats:      &diagnose.AppStats,
 		OutputChannel: outputItems,
diff --git a/tap/tlstapper/tls_tapper.go b/tap/tlstapper/tls_tapper.go
index 29fcd3e0b..c898d5dd9 100644
--- a/tap/tlstapper/tls_tapper.go
+++ b/tap/tlstapper/tls_tapper.go
@@ -86,6 +86,10 @@ func (t *TlsTapper) GlobalGolangTap(procfs string, pid string) error {
 	return t.tapGolangPid(procfs, uint32(_pid), api.UNKNOWN_NAMESPACE)
 }
 
+func (t *TlsTapper) GlobalGolangTapPath(exePath string) error {
+	return t.tapGolangPath(exePath)
+}
+
 func (t *TlsTapper) AddSsllibPid(procfs string, pid uint32, namespace string) error {
 	sslLibrary, err := findSsllib(procfs, pid)
 
@@ -219,6 +223,18 @@ func (t *TlsTapper) tapGolangPid(procfs string, pid uint32, namespace string) er
 	return nil
 }
 
+func (t *TlsTapper) tapGolangPath(exePath string) error {
+	hooks := golangHooks{}
+
+	if err := hooks.installUprobes(&t.bpfObjects, exePath); err != nil {
+		return err
+	}
+
+	t.golangHooksStructs = append(t.golangHooksStructs, hooks)
+
+	return nil
+}
+
 func LogError(err error) {
 	var e *errors.Error
 	if errors.As(err, &e) {