Add tests for how unbound subkeys are handled in KeyRingInfo

pgpainless-core/src/test/java/org/pgpainless/key/info/KeyRingInfoTest.java

@@ -35,6 +35,7 @@ import org.junit.jupiter.params.ParameterizedTest;
 import org.junit.jupiter.params.provider.MethodSource;
 import org.pgpainless.PGPainless;
 import org.pgpainless.algorithm.CompressionAlgorithm;
+import org.pgpainless.algorithm.EncryptionPurpose;
 import org.pgpainless.algorithm.HashAlgorithm;
 import org.pgpainless.algorithm.KeyFlag;
 import org.pgpainless.algorithm.PublicKeyAlgorithm;
@@ -640,4 +641,77 @@ public class KeyRingInfoTest {
         assertEquals(preferredSymmetricAlgorithms, info.getPreferredSymmetricKeyAlgorithms(null, skid2));
 
     }
+
+    @Test
+    public void testUnboundSubkeyIsIgnored() throws IOException {
+        // Contains unbound subkey D622C916384E0F6D364907E55D918BBD521CCD10
+        String KEY = "-----BEGIN PGP PUBLIC KEY BLOCK-----\n" +
+                "\n" +
+                "xsDNBF2lnPIBDAC5cL9PQoQLTMuhjbYvb4Ncuuo0bfmgPRFywX53jPhoFf4Zg6mv\n" +
+                "/seOXpgecTdOcVttfzC8ycIKrt3aQTiwOG/ctaR4Bk/t6ayNFfdUNxHWk4WCKzdz\n" +
+                "/56fW2O0F23qIRd8UUJp5IIlN4RDdRCtdhVQIAuzvp2oVy/LaS2kxQoKvph/5pQ/\n" +
+                "5whqsyroEWDJoSV0yOb25B/iwk/pLUFoyhDG9bj0kIzDxrEqW+7Ba8nocQlecMF3\n" +
+                "X5KMN5kp2zraLv9dlBBpWW43XktjcCZgMy20SouraVma8Je/ECwUWYUiAZxLIlMv\n" +
+                "9CurEOtxUw6N3RdOtLmYZS9uEnn5y1UkF88o8Nku890uk6BrewFzJyLAx5wRZ4F0\n" +
+                "qV/yq36UWQ0JB/AUGhHVPdFf6pl6eaxBwT5GXvbBUibtf8YI2og5RsgTWtXfU7eb\n" +
+                "SGXrl5ZMpbA6mbfhd0R8aPxWfmDWiIOhBufhMCvUHh1sApMKVZnvIff9/0Dca3wb\n" +
+                "vLIwa3T4CyshfT0AEQEAAc0hQm9iIEJhYmJhZ2UgPGJvYkBvcGVucGdwLmV4YW1w\n" +
+                "bGU+wsEOBBMBCgA4AhsDBQsJCAcCBhUKCQgLAgQWAgMBAh4BAheAFiEE0aZuGiOx\n" +
+                "gsmYD3iM+/zIKgFeczAFAl2lnvoACgkQ+/zIKgFeczBvbAv/VNk90a6hG8Od9xTz\n" +
+                "XxH5YRFUSGfIA1yjPIVOnKqhMwps2U+sWE3urL+MvjyQRlyRV8oY9IOhQ5Esm6DO\n" +
+                "ZYrTnE7qVETm1ajIAP2OFChEc55uH88x/anpPOXOJY7S8jbn3naC9qad75BrZ+3g\n" +
+                "9EBUWiy5p8TykP05WSnSxNRt7vFKLfEB4nGkehpwHXOVF0CRNwYle42bg8lpmdXF\n" +
+                "DcCZCi+qEbafmTQzkAqyzS3nCh3IAqq6Y0kBuaKLm2tSNUOlZbD+OHYQNZ5Jix7c\n" +
+                "ZUzs6Xh4+I55NRWl5smrLq66yOQoFPy9jot/Qxikx/wP3MsAzeGaZSEPc0fHp5G1\n" +
+                "6rlGbxQ3vl8/usUV7W+TMEMljgwd5x8POR6HC8EaCDfVnUBCPi/Gv+egLjsIbPJZ\n" +
+                "ZEroiE40e6/UoCiQtlpQB5exPJYSd1Q1txCwueih99PHepsDhmUQKiACszNU+RRo\n" +
+                "zAYau2VdHqnRJ7QYdxHDiH49jPK4NTMyb/tJh2TiIwcmsIpGzsDNBF2lnPIBDADW\n" +
+                "ML9cbGMrp12CtF9b2P6z9TTT74S8iyBOzaSvdGDQY/sUtZXRg21HWamXnn9sSXvI\n" +
+                "DEINOQ6A9QxdxoqWdCHrOuW3ofneYXoG+zeKc4dC86wa1TR2q9vW+RMXSO4uImA+\n" +
+                "Uzula/6k1DogDf28qhCxMwG/i/m9g1c/0aApuDyKdQ1PXsHHNlgd/Dn6rrd5y2AO\n" +
+                "baifV7wIhEJnvqgFXDN2RXGjLeCOHV4Q2WTYPg/S4k1nMXVDwZXrvIsA0YwIMgIT\n" +
+                "86Rafp1qKlgPNbiIlC1g9RY/iFaGN2b4Ir6GDohBQSfZW2+LXoPZuVE/wGlQ01rh\n" +
+                "827KVZW4lXvqsge+wtnWlszcselGATyzqOK9LdHPdZGzROZYI2e8c+paLNDdVPL6\n" +
+                "vdRBUnkCaEkOtl1mr2JpQi5nTU+gTX4IeInC7E+1a9UDF/Y85ybUz8XV8rUnR76U\n" +
+                "qVC7KidNepdHbZjjXCt8/Zo+Tec9JNbYNQB/e9ExmDntmlHEsSEQzFwzj8sxH48A\n" +
+                "EQEAAcLA9gQYAQoAIBYhBNGmbhojsYLJmA94jPv8yCoBXnMwBQJdpZzyAhsMAAoJ\n" +
+                "EPv8yCoBXnMw6f8L/26C34dkjBffTzMj5Bdzm8MtF67OYneJ4TQMw7+41IL4rVcS\n" +
+                "KhIhk/3Ud5knaRtP2ef1+5F66h9/RPQOJ5+tvBwhBAcUWSupKnUrdVaZQanYmtSx\n" +
+                "cVV2PL9+QEiNN3tzluhaWO//rACxJ+K/ZXQlIzwQVTpNhfGzAaMVV9zpf3u0k14i\n" +
+                "tcv6alKY8+rLZvO1wIIeRZLmU0tZDD5HtWDvUV7rIFI1WuoLb+KZgbYn3OWjCPHV\n" +
+                "dTrdZ2CqnZbG3SXw6awH9bzRLV9EXkbhIMez0deCVdeo+wFFklh8/5VK2b0vk/+w\n" +
+                "qMJxfpa1lHvJLobzOP9fvrswsr92MA2+k901WeISR7qEzcI0Fdg8AyFAExaEK6Vy\n" +
+                "jP7SXGLwvfisw34OxuZr3qmx1Sufu4toH3XrB7QJN8XyqqbsGxUCBqWif9RSK4xj\n" +
+                "zRTe56iPeiSJJOIciMP9i2ldI+KgLycyeDvGoBj0HCLO3gVaBe4ubVrj5KjhX2PV\n" +
+                "NEJd3XZRzaXZE2aAMc7ATQRhaDWyAQgA1CaZPxLUMm7sH0i/KTWVqqFgTTxVJjy+\n" +
+                "Aj3vjhrzAsQw1gqtbLXTlwBVVqhGIisEf7ZsFBBIzXNXi2Gk2O8HiZoKyey87f4R\n" +
+                "MkVCmHZKJyL2vBhsl8bfHI8rK41XeVmmpGnM+pUgD2MSoBbyDZKqhr3+zsnJD4gt\n" +
+                "hNMEYmZkqOzO20c1TO/92qPmmNn8hFa7sRqcff4TEzy3SsYUxsXvV/FjCfVNC3ij\n" +
+                "2u3RlB/8xljVjXhtrvlyl5uwmjJYs2fR9RHQPfhQt0YvcXw5ihCcLK0mu2FP0qT+\n" +
+                "C9h35EjDuD+1COXUOoW2B8LX6m2yf8cY72K70QgtGemj7UWhXL5u/wARAQAB\n" +
+                "=A3B8\n" +
+                "-----END PGP PUBLIC KEY BLOCK-----\n";
+
+        PGPPublicKeyRing certificate = PGPainless.readKeyRing().publicKeyRing(KEY);
+        OpenPgpV4Fingerprint unboundKey = new OpenPgpV4Fingerprint("D622C916384E0F6D364907E55D918BBD521CCD10");
+        KeyRingInfo info = PGPainless.inspectKeyRing(certificate);
+
+        assertFalse(info.isKeyValidlyBound(unboundKey.getKeyId()));
+
+        List<PGPPublicKey> encryptionSubkeys = info.getEncryptionSubkeys(EncryptionPurpose.STORAGE_AND_COMMUNICATIONS);
+        assertTrue(encryptionSubkeys.stream().map(OpenPgpV4Fingerprint::new).noneMatch(f -> f.equals(unboundKey)),
+                "Unbound subkey MUST NOT be considered a valid encryption subkey");
+
+        List<PGPPublicKey> signingSubkeys = info.getSigningSubkeys();
+        assertTrue(signingSubkeys.stream().map(OpenPgpV4Fingerprint::new).noneMatch(f -> f.equals(unboundKey)),
+                "Unbound subkey MUST NOT be considered a valid signing subkey");
+
+        assertTrue(info.getKeyFlagsOf(unboundKey.getKeyId()).isEmpty());
+
+        Date latestModification = info.getLastModified();
+        Date latestKeyCreation = info.getLatestKeyCreationDate();
+        Date unboundKeyCreation = certificate.getPublicKey(unboundKey.getKeyId()).getCreationTime();
+        assertTrue(unboundKeyCreation.after(latestModification));
+        assertTrue(unboundKeyCreation.after(latestKeyCreation));
+    }
 }