feat(pipeline): PLC/SPS control-logic security scanner (IEC 61131-3) (#162)

2026-07-16 08:31:43 +00:00
parent a981311413
commit 6d02b138c6
13 changed files with 2599 additions and 8 deletions
@@ -0,0 +1,57 @@
+(*
+ * Demo PLC program — pump-station control (IEC 61131-3 Structured Text).
+ *
+ * Deliberately vulnerable, for the compliance-scanner PLC control-logic demo.
+ * Each issue below is flagged by pipeline::plc::rules.
+ *)
+
+FUNCTION_BLOCK PumpStationCtrl
+VAR_INPUT
+    OperatorCmd   : INT;        (* HMI command index — untrusted *)
+    FlowSetpoint  : REAL;
+END_VAR
+VAR_OUTPUT
+    PumpSpeed     : REAL;
+    Fault         : BOOL;
+END_VAR
+VAR
+    HmiPassword     : STRING := 'admin123';        (* hardcoded + default credential *)
+    ApiKey          : STRING := 'sk_live_9c1f2a';   (* hardcoded secret *)
+    PumpProfiles    : ARRAY[0..7] OF REAL;
+    Safety_Enable   : BOOL := TRUE;
+    Watchdog_Kick   : INT := 1;
+    MeasuredFlow    : REAL;
+    ScaleFactor     : REAL;
+    i               : INT;
+END_VAR
+
+    (* Operator can index the profile table with an unvalidated command. *)
+    PumpSpeed := PumpProfiles[OperatorCmd];
+
+    (* Divisor is a live process value that can read zero on a stopped line. *)
+    ScaleFactor := FlowSetpoint / MeasuredFlow;
+
+    (* Safety interlock disabled straight from application logic. *)
+    IF OperatorCmd = 99 THEN
+        Safety_Enable := FALSE;
+        Watchdog_Kick := 0;
+    END_IF;
+
+    (* Unauthenticated Modbus/TCP link on the cleartext OT port. *)
+    Modbus_TCP_Connect(IP := '10.10.5.20', PORT := 502, AUTH := FALSE, PASSWORD := 'plc');
+
+    (* Unstructured jump around the fault handler. *)
+    IF MeasuredFlow > 1000.0 THEN
+        JMP trip;
+    END_IF;
+
+    (* A correctly guarded division — must NOT be flagged. *)
+    IF ScaleFactor <> 0.0 THEN
+        PumpSpeed := PumpSpeed / ScaleFactor;
+    END_IF;
+
+    RETURN;
+trip:
+    Fault := TRUE;
+    PumpSpeed := 0.0;
+END_FUNCTION_BLOCK