feat(applet): DeviceRequestParser structural validation (M2D.1)

2026-06-17 16:19:12 -07:00
parent d5945be60e
commit a7bc7e4478
2 changed files with 408 additions and 0 deletions
--- a/applet/src/test/java/com/dangerousthings/aliro/DeviceRequestParserTest.java
+++ b/applet/src/test/java/com/dangerousthings/aliro/DeviceRequestParserTest.java
@@ -0,0 +1,91 @@
+package com.dangerousthings.aliro;
+
+import javacard.framework.ISO7816;
+import javacard.framework.ISOException;
+import org.junit.jupiter.api.Test;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+
+/**
+ * Tests for {@link DeviceRequestParser} — structural validation of the inbound
+ * mdoc DeviceRequest (ISO 18013-5 §8.3.2.1).
+ *
+ * <p>M2D's ENVELOPE handler receives a DeviceRequest, must confirm its shape
+ * before discarding the contents (we always return our single Access Document),
+ * and reject malformed input with the canonical SW codes:
+ * <ul>
+ *   <li>{@code SW_DATA_INVALID (0x6984)} — malformed CBOR or wrong shape</li>
+ *   <li>{@code SW_CONDITIONS_NOT_SATISFIED (0x6985)} — unsupported version</li>
+ * </ul>
+ *
+ * <p>Test vectors were generated via cbor2 (canonical encoding); see the
+ * generator script in the M2D.1 plan. The Python equivalents:
+ * <pre>
+ *   VALID         = cbor2.dumps({"version":"1.0","docRequests":[{"itemsRequest":cbor2.dumps({"docType":"org.iso.18013.5.1.mDL","nameSpaces":{}})}]}, canonical=True)
+ *   BAD_VERSION   = cbor2.dumps({"version":"2.0","docRequests":[{"itemsRequest":b"\x40"}]}, canonical=True)
+ *   TRUNCATED     = VALID[:8]
+ * </pre>
+ */
+class DeviceRequestParserTest {
+
+    /**
+     * Canonical CBOR for a minimal-but-valid DeviceRequest:
+     * {@code {"version":"1.0","docRequests":[{"itemsRequest":<bstr>}]}}
+     * with itemsRequest containing an inner CBOR
+     * {@code {"docType":"org.iso.18013.5.1.mDL","nameSpaces":{}}}.
+     */
+    private static final byte[] VALID = hex(
+        "a26776657273696f6e63312e306b646f63526571756573747381"
+      + "a16c6974656d7352657175657374582ba267646f6354797065"
+      + "756f72672e69736f2e31383031332e352e312e6d444c"
+      + "6a6e616d65537061636573a0");
+
+    /** Same shape as VALID but version tstr value is "2.0". */
+    private static final byte[] BAD_VERSION = hex(
+        "a26776657273696f6e63322e306b646f63526571756573747381"
+      + "a16c6974656d73526571756573744140");
+
+    /** First 8 bytes of VALID — truncated mid-key, malformed CBOR. */
+    private static final byte[] TRUNCATED = hex("a26776657273696f");
+
+    @Test
+    void parseDeviceRequest_validShape_returnsOk() {
+        byte[] scratch = new byte[4];
+        // Should not throw.
+        DeviceRequestParser.validate(
+            VALID, (short) 0, (short) VALID.length,
+            scratch, (short) 0);
+    }
+
+    @Test
+    void parseDeviceRequest_unknownVersion_throwsConditionsNotSatisfied() {
+        byte[] scratch = new byte[4];
+        ISOException ex = assertThrows(ISOException.class, () ->
+            DeviceRequestParser.validate(
+                BAD_VERSION, (short) 0, (short) BAD_VERSION.length,
+                scratch, (short) 0));
+        assertEquals(ISO7816.SW_CONDITIONS_NOT_SATISFIED, ex.getReason(),
+            "unknown version must throw SW_CONDITIONS_NOT_SATISFIED (0x6985)");
+    }
+
+    @Test
+    void parseDeviceRequest_malformedCbor_throwsDataInvalid() {
+        byte[] scratch = new byte[4];
+        ISOException ex = assertThrows(ISOException.class, () ->
+            DeviceRequestParser.validate(
+                TRUNCATED, (short) 0, (short) TRUNCATED.length,
+                scratch, (short) 0));
+        assertEquals(ISO7816.SW_DATA_INVALID, ex.getReason(),
+            "truncated CBOR must throw SW_DATA_INVALID (0x6984)");
+    }
+
+    private static byte[] hex(String s) {
+        s = s.replaceAll("\\s+", "");
+        byte[] out = new byte[s.length() / 2];
+        for (int i = 0; i < out.length; i++) {
+            out[i] = (byte) Integer.parseInt(s.substring(i * 2, i * 2 + 2), 16);
+        }
+        return out;
+    }
+}