Add basic tests for IKEv2/IPsec VPNs

This change adds basic tests for all IKEv2/IPsec VPN public APIs.
Additional testing for ensuring IKEv2 setup completes will be done in a
subsequent CL.

Bug: 148582947
Test: Ikev2VpnTest added
Change-Id: Ia5d35c32525b32be4a0dc0584630f5bb9e7f1bcb
diff --git a/tests/cts/net/src/android/net/cts/Ikev2VpnTest.java b/tests/cts/net/src/android/net/cts/Ikev2VpnTest.java
new file mode 100644
index 0000000..8c1cbbb
--- /dev/null
+++ b/tests/cts/net/src/android/net/cts/Ikev2VpnTest.java
@@ -0,0 +1,357 @@
+/*
+ * Copyright (C) 2020 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.net.cts;
+
+import static com.android.compatibility.common.util.SystemUtil.runWithShellPermissionIdentity;
+
+import static org.junit.Assert.assertArrayEquals;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+import static org.junit.Assume.assumeTrue;
+
+import android.Manifest;
+import android.annotation.NonNull;
+import android.app.AppOpsManager;
+import android.content.Context;
+import android.content.Intent;
+import android.net.ConnectivityManager;
+import android.net.Ikev2VpnProfile;
+import android.net.IpSecAlgorithm;
+import android.net.ProxyInfo;
+import android.net.VpnManager;
+import android.net.cts.util.CtsNetUtils;
+import android.platform.test.annotations.AppModeFull;
+
+import androidx.test.InstrumentationRegistry;
+import androidx.test.runner.AndroidJUnit4;
+
+import com.android.org.bouncycastle.x509.X509V1CertificateGenerator;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import java.math.BigInteger;
+import java.security.KeyPair;
+import java.security.KeyPairGenerator;
+import java.security.PrivateKey;
+import java.security.cert.X509Certificate;
+import java.util.Arrays;
+import java.util.Date;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+
+import javax.security.auth.x500.X500Principal;
+
+@RunWith(AndroidJUnit4.class)
+@AppModeFull(reason = "Appops state changes disallowed for instant apps (OP_ACTIVATE_PLATFORM_VPN)")
+public class Ikev2VpnTest {
+    private static final String TAG = Ikev2VpnTest.class.getSimpleName();
+
+    private static final String TEST_SERVER_ADDR = "2001:db8::1";
+    private static final String TEST_IDENTITY = "client.cts.android.com";
+    private static final List<String> TEST_ALLOWED_ALGORITHMS =
+            Arrays.asList(IpSecAlgorithm.AUTH_CRYPT_AES_GCM);
+
+    private static final ProxyInfo TEST_PROXY_INFO =
+            ProxyInfo.buildDirectProxy("proxy.cts.android.com", 1234);
+    private static final int TEST_MTU = 1300;
+
+    private static final byte[] TEST_PSK = "ikev2".getBytes();
+    private static final String TEST_USER = "username";
+    private static final String TEST_PASSWORD = "pa55w0rd";
+
+    // Static state to reduce setup/teardown
+    private static final Context sContext = InstrumentationRegistry.getContext();
+    private static final ConnectivityManager sCM =
+            (ConnectivityManager) sContext.getSystemService(Context.CONNECTIVITY_SERVICE);
+    private static final VpnManager sVpnMgr =
+            (VpnManager) sContext.getSystemService(Context.VPN_MANAGEMENT_SERVICE);
+    private static final CtsNetUtils mCtsNetUtils = new CtsNetUtils(sContext);
+
+    private final X509Certificate mServerRootCa;
+    private final CertificateAndKey mUserCertKey;
+
+    public Ikev2VpnTest() throws Exception {
+        // Build certificates
+        mServerRootCa = generateRandomCertAndKeyPair().cert;
+        mUserCertKey = generateRandomCertAndKeyPair();
+    }
+
+    /**
+     * Sets the given appop using shell commands
+     *
+     * <p>This method must NEVER be called from within a shell permission, as it will attempt to
+     * acquire, and then drop the shell permission identity. This results in the caller losing the
+     * shell permission identity due to these calls not being reference counted.
+     */
+    public void setAppop(int appop, boolean allow) {
+        // Requires shell permission to update appops.
+        runWithShellPermissionIdentity(() -> {
+            mCtsNetUtils.setAppopPrivileged(appop, allow);
+        }, Manifest.permission.MANAGE_TEST_NETWORKS);
+    }
+
+    private Ikev2VpnProfile buildIkev2VpnProfileCommon(
+            Ikev2VpnProfile.Builder builder, boolean isRestrictedToTestNetworks) throws Exception {
+        if (isRestrictedToTestNetworks) {
+            builder.restrictToTestNetworks();
+        }
+
+        return builder.setBypassable(true)
+                .setProxy(TEST_PROXY_INFO)
+                .setMaxMtu(TEST_MTU)
+                .setMetered(false)
+                .setAllowedAlgorithms(TEST_ALLOWED_ALGORITHMS)
+                .build();
+    }
+
+    private Ikev2VpnProfile buildIkev2VpnProfilePsk(boolean isRestrictedToTestNetworks)
+            throws Exception {
+        final Ikev2VpnProfile.Builder builder =
+                new Ikev2VpnProfile.Builder(TEST_SERVER_ADDR, TEST_IDENTITY).setAuthPsk(TEST_PSK);
+
+        return buildIkev2VpnProfileCommon(builder, isRestrictedToTestNetworks);
+    }
+
+    private Ikev2VpnProfile buildIkev2VpnProfileUsernamePassword(boolean isRestrictedToTestNetworks)
+            throws Exception {
+        final Ikev2VpnProfile.Builder builder =
+                new Ikev2VpnProfile.Builder(TEST_SERVER_ADDR, TEST_IDENTITY)
+                        .setAuthUsernamePassword(TEST_USER, TEST_PASSWORD, mServerRootCa);
+
+        return buildIkev2VpnProfileCommon(builder, isRestrictedToTestNetworks);
+    }
+
+    private Ikev2VpnProfile buildIkev2VpnProfileDigitalSignature(boolean isRestrictedToTestNetworks)
+            throws Exception {
+        final Ikev2VpnProfile.Builder builder =
+                new Ikev2VpnProfile.Builder(TEST_SERVER_ADDR, TEST_IDENTITY)
+                        .setAuthDigitalSignature(
+                                mUserCertKey.cert, mUserCertKey.key, mServerRootCa);
+
+        return buildIkev2VpnProfileCommon(builder, isRestrictedToTestNetworks);
+    }
+
+    private void checkBasicIkev2VpnProfile(@NonNull Ikev2VpnProfile profile) throws Exception {
+        assertEquals(TEST_SERVER_ADDR, profile.getServerAddr());
+        assertEquals(TEST_IDENTITY, profile.getUserIdentity());
+        assertEquals(TEST_PROXY_INFO, profile.getProxyInfo());
+        assertEquals(TEST_ALLOWED_ALGORITHMS, profile.getAllowedAlgorithms());
+        assertTrue(profile.isBypassable());
+        assertFalse(profile.isMetered());
+        assertEquals(TEST_MTU, profile.getMaxMtu());
+        assertFalse(profile.isRestrictedToTestNetworks());
+    }
+
+    @Test
+    public void testBuildIkev2VpnProfilePsk() throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        final Ikev2VpnProfile profile =
+                buildIkev2VpnProfilePsk(false /* isRestrictedToTestNetworks */);
+
+        checkBasicIkev2VpnProfile(profile);
+        assertArrayEquals(TEST_PSK, profile.getPresharedKey());
+
+        // Verify nothing else is set.
+        assertNull(profile.getUsername());
+        assertNull(profile.getPassword());
+        assertNull(profile.getServerRootCaCert());
+        assertNull(profile.getRsaPrivateKey());
+        assertNull(profile.getUserCert());
+    }
+
+    @Test
+    public void testBuildIkev2VpnProfileUsernamePassword() throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        final Ikev2VpnProfile profile =
+                buildIkev2VpnProfileUsernamePassword(false /* isRestrictedToTestNetworks */);
+
+        checkBasicIkev2VpnProfile(profile);
+        assertEquals(TEST_USER, profile.getUsername());
+        assertEquals(TEST_PASSWORD, profile.getPassword());
+        assertEquals(mServerRootCa, profile.getServerRootCaCert());
+
+        // Verify nothing else is set.
+        assertNull(profile.getPresharedKey());
+        assertNull(profile.getRsaPrivateKey());
+        assertNull(profile.getUserCert());
+    }
+
+    @Test
+    public void testBuildIkev2VpnProfileDigitalSignature() throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        final Ikev2VpnProfile profile =
+                buildIkev2VpnProfileDigitalSignature(false /* isRestrictedToTestNetworks */);
+
+        checkBasicIkev2VpnProfile(profile);
+        assertEquals(mUserCertKey.cert, profile.getUserCert());
+        assertEquals(mUserCertKey.key, profile.getRsaPrivateKey());
+        assertEquals(mServerRootCa, profile.getServerRootCaCert());
+
+        // Verify nothing else is set.
+        assertNull(profile.getUsername());
+        assertNull(profile.getPassword());
+        assertNull(profile.getPresharedKey());
+    }
+
+    private void verifyProvisionVpnProfile(
+            boolean hasActivateVpn, boolean hasActivatePlatformVpn, boolean expectIntent)
+            throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        setAppop(AppOpsManager.OP_ACTIVATE_VPN, hasActivateVpn);
+        setAppop(AppOpsManager.OP_ACTIVATE_PLATFORM_VPN, hasActivatePlatformVpn);
+
+        final Ikev2VpnProfile profile =
+                buildIkev2VpnProfilePsk(false /* isRestrictedToTestNetworks */);
+        final Intent intent = sVpnMgr.provisionVpnProfile(profile);
+        assertEquals(expectIntent, intent != null);
+    }
+
+    @Test
+    public void testProvisionVpnProfileNoPreviousConsent() throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        verifyProvisionVpnProfile(false /* hasActivateVpn */,
+                false /* hasActivatePlatformVpn */, true /* expectIntent */);
+    }
+
+    @Test
+    public void testProvisionVpnProfilePlatformVpnConsented() throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        verifyProvisionVpnProfile(false /* hasActivateVpn */,
+                true /* hasActivatePlatformVpn */, false /* expectIntent */);
+    }
+
+    @Test
+    public void testProvisionVpnProfileVpnServiceConsented() throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        verifyProvisionVpnProfile(true /* hasActivateVpn */,
+                false /* hasActivatePlatformVpn */, false /* expectIntent */);
+    }
+
+    @Test
+    public void testProvisionVpnProfileAllPreConsented() throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        verifyProvisionVpnProfile(true /* hasActivateVpn */,
+                true /* hasActivatePlatformVpn */, false /* expectIntent */);
+    }
+
+    @Test
+    public void testDeleteVpnProfile() throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        setAppop(AppOpsManager.OP_ACTIVATE_PLATFORM_VPN, true);
+
+        final Ikev2VpnProfile profile =
+                buildIkev2VpnProfilePsk(false /* isRestrictedToTestNetworks */);
+        assertNull(sVpnMgr.provisionVpnProfile(profile));
+
+        // Verify that deleting the profile works (even without the appop)
+        setAppop(AppOpsManager.OP_ACTIVATE_PLATFORM_VPN, false);
+        sVpnMgr.deleteProvisionedVpnProfile();
+
+        // Test that the profile was deleted - starting it should throw an IAE.
+        try {
+            setAppop(AppOpsManager.OP_ACTIVATE_PLATFORM_VPN, true);
+            sVpnMgr.startProvisionedVpnProfile();
+            fail("Expected IllegalArgumentException due to missing profile");
+        } catch (IllegalArgumentException expected) {
+        }
+    }
+
+    @Test
+    public void testStartVpnProfileNoPreviousConsent() throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        setAppop(AppOpsManager.OP_ACTIVATE_VPN, false);
+        setAppop(AppOpsManager.OP_ACTIVATE_PLATFORM_VPN, false);
+
+        // Make sure the VpnProfile is not provisioned already.
+        sVpnMgr.stopProvisionedVpnProfile();
+
+        try {
+            sVpnMgr.startProvisionedVpnProfile();
+            fail("Expected SecurityException for missing consent");
+        } catch (SecurityException expected) {
+        }
+    }
+
+    @Test
+    public void testStartStopVpnProfile() throws Exception {
+        assumeTrue(mCtsNetUtils.hasIpsecTunnelsFeature());
+
+        // Requires MANAGE_TEST_NETWORKS to provision a test-mode profile.
+        runWithShellPermissionIdentity(() -> {
+            mCtsNetUtils.setAppopPrivileged(AppOpsManager.OP_ACTIVATE_PLATFORM_VPN, true);
+
+            final Ikev2VpnProfile profile =
+                    buildIkev2VpnProfilePsk(true /* isRestrictedToTestNetworks */);
+            assertNull(sVpnMgr.provisionVpnProfile(profile));
+
+            sVpnMgr.startProvisionedVpnProfile();
+            // TODO: When IKEv2 setup is injectable, verify network was set up properly.
+
+            sVpnMgr.stopProvisionedVpnProfile();
+            // TODO: When IKEv2 setup is injectable, verify network is lost.
+        }, Manifest.permission.MANAGE_TEST_NETWORKS);
+    }
+
+    private static class CertificateAndKey {
+        public final X509Certificate cert;
+        public final PrivateKey key;
+
+        CertificateAndKey(X509Certificate cert, PrivateKey key) {
+            this.cert = cert;
+            this.key = key;
+        }
+    }
+
+    private static CertificateAndKey generateRandomCertAndKeyPair() throws Exception {
+        final Date validityBeginDate =
+                new Date(System.currentTimeMillis() - TimeUnit.DAYS.toMillis(1L));
+        final Date validityEndDate =
+                new Date(System.currentTimeMillis() + TimeUnit.DAYS.toMillis(1L));
+
+        // Generate a keypair
+        final KeyPairGenerator keyPairGenerator = KeyPairGenerator.getInstance("RSA");
+        keyPairGenerator.initialize(512);
+        final KeyPair keyPair = keyPairGenerator.generateKeyPair();
+
+        final X500Principal dnName = new X500Principal("CN=test.android.com");
+        final X509V1CertificateGenerator certGen = new X509V1CertificateGenerator();
+        certGen.setSerialNumber(BigInteger.valueOf(System.currentTimeMillis()));
+        certGen.setSubjectDN(dnName);
+        certGen.setIssuerDN(dnName);
+        certGen.setNotBefore(validityBeginDate);
+        certGen.setNotAfter(validityEndDate);
+        certGen.setPublicKey(keyPair.getPublic());
+        certGen.setSignatureAlgorithm("SHA256WithRSAEncryption");
+
+        final X509Certificate cert = certGen.generate(keyPair.getPrivate(), "AndroidOpenSSL");
+        return new CertificateAndKey(cert, keyPair.getPrivate());
+    }
+}