1 files changed, 139 insertions, 0 deletions
diff --git a/src/internal/syscall/windows/exec_windows_test.go b/src/internal/syscall/windows/exec_windows_test.go
new file mode 100644
index 0000000..3311da5
--- /dev/null
+++ b/src/internal/syscall/windows/exec_windows_test.go
@@ -0,0 +1,139 @@
+// Copyright 2017 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+//go:build windows
+
+package windows_test
+
+import (
+	"fmt"
+	"internal/syscall/windows"
+	"os"
+	"os/exec"
+	"syscall"
+	"testing"
+	"unsafe"
+)
+
+func TestRunAtLowIntegrity(t *testing.T) {
+	if os.Getenv("GO_WANT_HELPER_PROCESS") == "1" {
+		wil, err := getProcessIntegrityLevel()
+		if err != nil {
+			fmt.Fprintf(os.Stderr, "error: %s\n", err.Error())
+			os.Exit(9)
+			return
+		}
+		fmt.Printf("%s", wil)
+		os.Exit(0)
+		return
+	}
+
+	cmd := exec.Command(os.Args[0], "-test.run=TestRunAtLowIntegrity", "--")
+	cmd.Env = []string{"GO_WANT_HELPER_PROCESS=1"}
+
+	token, err := getIntegrityLevelToken(sidWilLow)
+	if err != nil {
+		t.Fatal(err)
+	}
+	defer token.Close()
+
+	cmd.SysProcAttr = &syscall.SysProcAttr{
+		Token: token,
+	}
+
+	out, err := cmd.CombinedOutput()
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if string(out) != sidWilLow {
+		t.Fatalf("Child process did not run as low integrity level: %s", string(out))
+	}
+}
+
+const (
+	sidWilLow = `S-1-16-4096`
+)
+
+func getProcessIntegrityLevel() (string, error) {
+	procToken, err := syscall.OpenCurrentProcessToken()
+	if err != nil {
+		return "", err
+	}
+	defer procToken.Close()
+
+	p, err := tokenGetInfo(procToken, syscall.TokenIntegrityLevel, 64)
+	if err != nil {
+		return "", err
+	}
+
+	tml := (*windows.TOKEN_MANDATORY_LABEL)(p)
+
+	sid := (*syscall.SID)(unsafe.Pointer(tml.Label.Sid))
+
+	return sid.String()
+}
+
+func tokenGetInfo(t syscall.Token, class uint32, initSize int) (unsafe.Pointer, error) {
+	n := uint32(initSize)
+	for {
+		b := make([]byte, n)
+		e := syscall.GetTokenInformation(t, class, &b[0], uint32(len(b)), &n)
+		if e == nil {
+			return unsafe.Pointer(&b[0]), nil
+		}
+		if e != syscall.ERROR_INSUFFICIENT_BUFFER {
+			return nil, e
+		}
+		if n <= uint32(len(b)) {
+			return nil, e
+		}
+	}
+}
+
+func getIntegrityLevelToken(wns string) (syscall.Token, error) {
+	var procToken, token syscall.Token
+
+	proc, err := syscall.GetCurrentProcess()
+	if err != nil {
+		return 0, err
+	}
+	defer syscall.CloseHandle(proc)
+
+	err = syscall.OpenProcessToken(proc,
+		syscall.TOKEN_DUPLICATE|
+			syscall.TOKEN_ADJUST_DEFAULT|
+			syscall.TOKEN_QUERY|
+			syscall.TOKEN_ASSIGN_PRIMARY,
+		&procToken)
+	if err != nil {
+		return 0, err
+	}
+	defer procToken.Close()
+
+	sid, err := syscall.StringToSid(wns)
+	if err != nil {
+		return 0, err
+	}
+
+	tml := &windows.TOKEN_MANDATORY_LABEL{}
+	tml.Label.Attributes = windows.SE_GROUP_INTEGRITY
+	tml.Label.Sid = sid
+
+	err = windows.DuplicateTokenEx(procToken, 0, nil, windows.SecurityImpersonation,
+		windows.TokenPrimary, &token)
+	if err != nil {
+		return 0, err
+	}
+
+	err = windows.SetTokenInformation(token,
+		syscall.TokenIntegrityLevel,
+		uintptr(unsafe.Pointer(tml)),
+		tml.Size())
+	if err != nil {
+		token.Close()
+		return 0, err
+	}
+	return token, nil
+}