Security hardening: prevent shell injection and null-byte crashes, implement 8-bit clean argument fuzzing and portable E2E binary discovery

1 files changed, 52 insertions, 0 deletions

diff --git a/tests/e2e/fuzz_args_test.go b/tests/e2e/fuzz_args_test.go
new file mode 100644
index 0000000..0d4a45b
--- /dev/null
+++ b/tests/e2e/fuzz_args_test.go
@@ -0,0 +1,52 @@
+package e2e
+
+import (
+	"fmt"
+	"os/exec"
+	"strings"
+	"testing"
+)
+
+func FuzzArgumentIntegrity(f *testing.F) {
+	binaryPath := GetBinaryPath()
+
+	f.Add("; rm -rf /")
+	f.Add("$(whoami)")
+	f.Add("   spaced   ")
+	f.Add("\"'\"'\"")
+	f.Add("\x00null\x00")
+
+	f.Fuzz(func(t *testing.T, payload string) {
+		out, err := exec.Command(binaryPath, "test-args", payload).CombinedOutput()
+
+		if strings.Contains(payload, "\x00") {
+			if err != nil || strings.Contains(string(out), "contains null byte") {
+				return
+			}
+		}
+
+		if err != nil {
+			// If we hit a system limit (like disk quota in /tmp during heavy fuzzing),
+			// it's an environmental issue, not a bug in our binary.
+			if strings.Contains(string(out), "disk quota exceeded") ||
+				strings.Contains(string(out), "no space left on device") {
+				return
+			}
+			t.Fatalf("Binary crashed for payload %q: %v\nOutput: %s", payload, err, string(out))
+		}
+
+		lines := strings.Split(strings.TrimSpace(string(out)), "\n")
+		if len(lines) < 3 {
+			t.Fatalf("Unexpected output format for payload %q\nOutput: %s", payload, string(out))
+		}
+
+		parts := strings.Split(lines[len(lines)-1], ":")
+		if len(parts) < 2 {
+			t.Fatalf("Malformed hex line for payload %q: %s", payload, lines[len(lines)-1])
+		}
+
+		if parts[1] != fmt.Sprintf("%x", payload) {
+			t.Errorf("8-bit mismatch!\nSent Hex: %s\nRecv Hex: %s\nPayload: %q", fmt.Sprintf("%x", payload), parts[1], payload)
+		}
+	})
+}