Initial snapshot: Aliro applet, harness, Nucleo NFC10A1 reader port

Three components, all bench-validated to varying depths:

- applet/: CSA Aliro v1.0 Java Card applet for J3R180. AUTH0 + AUTH1
  expedited-standard flow end-to-end green via PC/SC bench reader
  (aliro-bench-test). Userland AES-256-GCM and HMAC-SHA-256 layered
  on top of J3R180's primitives because the card lacks both natively.
  P-256 curve params seeded explicitly per J3R180's quirk.

- harness/: Python orchestrator (aliro-trustgen, aliro-personalize,
  aliro-bench-test) for trust-bundle generation, card personalization
  via PersonalizationApplet, and PC/SC AUTH0+AUTH1 transactions. 126
  pytest cases passing.

- reader/STM32CubeExpansion_ALIRO_V1_0_0/: ST X-CUBE-ALIRO V1.0.0
  with our NFC10A1 port (NUCLEO-U545RE-Q + X-NUCLEO-NFC10A1, ST25R200
  shared with NFC09A1). nfc10-only/ project, NFC10A1 BSP shim,
  ALIRO_TRUST_OVERRIDE include into vendor's provisioning.c, and an
  ALIRO_APDU_TRACE wrapper around demoTransceiveBlocking. Boots,
  detects the J3R180, completes SELECT + AUTH0; AUTH1 currently fails
  with RFAL ERR_PROTO (0xB) — under investigation, see
  docs/plans/2026-04-20-nucleo-nfc10a1-port.md and bench-notes/.

Excluded: x-cube-aliro.zip vendor archive, harness/.venv, build dirs,
generated aliro_trust.h (contains private reader scalar), all PEMs.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

applet/src/test/java/com/dangerousthings/aliro/StepUpAppletTest.java

@@ -0,0 +1,77 @@
+package com.dangerousthings.aliro;
+
+import com.licel.jcardsim.smartcardio.CardSimulator;
+import javacard.framework.AID;
+import javax.smartcardio.CommandAPDU;
+import javax.smartcardio.ResponseAPDU;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+/**
+ * Tests for {@link StepUpApplet} — scaffold for the Aliro step-up phase
+ * (spec §8.4). This first pass only covers AID selection and
+ * INS-not-supported handling; the mdoc DeviceRequest/DeviceResponse +
+ * StepUpSK key derivation pipelines come in follow-up iterations.
+ */
+class StepUpAppletTest {
+
+    private CardSimulator sim;
+
+    @BeforeEach
+    void setUp() {
+        CredentialStore.get().resetForTesting();
+        sim = new CardSimulator();
+        AID aid = new AID(AliroAids.STEP_UP, (short) 0, (byte) AliroAids.STEP_UP.length);
+        sim.installApplet(aid, StepUpApplet.class);
+    }
+
+    @Test
+    void selectStepUpAidSucceeds() {
+        CommandAPDU select = new CommandAPDU(0x00, 0xA4, 0x04, 0x00, AliroAids.STEP_UP, 256);
+        ResponseAPDU r = sim.transmitCommand(select);
+        assertEquals(0x9000, r.getSW(), "SELECT of step-up AID must succeed");
+    }
+
+    @Test
+    void selectStepUpAidReturnsFciWithAid() {
+        CommandAPDU select = new CommandAPDU(0x00, 0xA4, 0x04, 0x00, AliroAids.STEP_UP, 256);
+        ResponseAPDU r = sim.transmitCommand(select);
+        byte[] aidFromFci = TlvUtil.findTopLevel(unwrap6F(r.getData()), 0x84);
+        org.junit.jupiter.api.Assertions.assertArrayEquals(AliroAids.STEP_UP, aidFromFci,
+            "FCI 84 tag must echo the step-up AID");
+    }
+
+    @Test
+    void unsupportedInsReturns6D00() {
+        CommandAPDU select = new CommandAPDU(0x00, 0xA4, 0x04, 0x00, AliroAids.STEP_UP, 256);
+        sim.transmitCommand(select);
+
+        // Some arbitrary unsupported INS under the proprietary class.
+        CommandAPDU bogus = new CommandAPDU(0x80, 0xFE, 0x00, 0x00, new byte[0], 256);
+        assertEquals(0x6D00, sim.transmitCommand(bogus).getSW(),
+            "unrecognized INS on step-up applet must return SW_INS_NOT_SUPPORTED");
+    }
+
+    @Test
+    void wrongClaReturns6E00() {
+        CommandAPDU select = new CommandAPDU(0x00, 0xA4, 0x04, 0x00, AliroAids.STEP_UP, 256);
+        sim.transmitCommand(select);
+
+        CommandAPDU wrongCla = new CommandAPDU(0x81, 0xC3, 0x00, 0x00, new byte[0], 256);
+        assertEquals(0x6E00, sim.transmitCommand(wrongCla).getSW(),
+            "wrong CLA must return SW_CLA_NOT_SUPPORTED");
+    }
+
+    /** Unwraps the outer 6F FCI template to expose its nested TLVs. */
+    private static byte[] unwrap6F(byte[] fci) {
+        if (fci.length < 2 || fci[0] != 0x6F) {
+            throw new IllegalArgumentException("expected a 6F-wrapped FCI template");
+        }
+        int len = fci[1] & 0xFF;
+        byte[] inner = new byte[len];
+        System.arraycopy(fci, 2, inner, 0, len);
+        return inner;
+    }
+}