Validate IpSecAlgorithm Length

Improve the Validation of IpSecAlgorithm by
explicitly checking the length in addition to
the truncation length (previously an oversight).
In addition, we now check the lengths during
un-parceling, which will catch someone maliciously
manually building a parcel and passing it, bypassing
the checks in the constructor.

Bug: 68780091
Test: runtest -x IpSecAlgorithmTest.java
Change-Id: I8172762617264d34f47d5144336464510f07a701

tests/net/java/android/net/IpSecAlgorithmTest.java

@@ -0,0 +1,115 @@
+/*
+ * Copyright (C) 2017 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;
+
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+import android.os.Parcel;
+import android.support.test.filters.SmallTest;
+import android.support.test.runner.AndroidJUnit4;
+import java.util.Arrays;
+import java.util.Random;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+/** Unit tests for {@link IpSecAlgorithm}. */
+@SmallTest
+@RunWith(AndroidJUnit4.class)
+public class IpSecAlgorithmTest {
+
+    private static final byte[] KEY_MATERIAL;
+
+    static {
+        KEY_MATERIAL = new byte[128];
+        new Random().nextBytes(KEY_MATERIAL);
+    };
+
+    @Test
+    public void testDefaultTruncLen() throws Exception {
+        IpSecAlgorithm explicit =
+                new IpSecAlgorithm(
+                        IpSecAlgorithm.AUTH_HMAC_SHA256, Arrays.copyOf(KEY_MATERIAL, 256 / 8), 256);
+        IpSecAlgorithm implicit =
+                new IpSecAlgorithm(
+                        IpSecAlgorithm.AUTH_HMAC_SHA256, Arrays.copyOf(KEY_MATERIAL, 256 / 8));
+        assertTrue(
+                "Default Truncation Length Incorrect, Explicit: "
+                        + explicit
+                        + "implicit: "
+                        + implicit,
+                IpSecAlgorithm.equals(explicit, implicit));
+    }
+
+    @Test
+    public void testTruncLenValidation() throws Exception {
+        for (int truncLen : new int[] {256, 512}) {
+            new IpSecAlgorithm(
+                    IpSecAlgorithm.AUTH_HMAC_SHA512,
+                    Arrays.copyOf(KEY_MATERIAL, 512 / 8),
+                    truncLen);
+        }
+
+        for (int truncLen : new int[] {255, 513}) {
+            try {
+                new IpSecAlgorithm(
+                        IpSecAlgorithm.AUTH_HMAC_SHA512,
+                        Arrays.copyOf(KEY_MATERIAL, 512 / 8),
+                        truncLen);
+                fail("Invalid truncation length not validated");
+            } catch (IllegalArgumentException pass) {
+            }
+        }
+    }
+
+    @Test
+    public void testLenValidation() throws Exception {
+        for (int len : new int[] {128, 192, 256}) {
+            new IpSecAlgorithm(IpSecAlgorithm.CRYPT_AES_CBC, Arrays.copyOf(KEY_MATERIAL, len / 8));
+        }
+        try {
+            new IpSecAlgorithm(IpSecAlgorithm.CRYPT_AES_CBC, Arrays.copyOf(KEY_MATERIAL, 384 / 8));
+            fail("Invalid key length not validated");
+        } catch (IllegalArgumentException pass) {
+        }
+    }
+
+    @Test
+    public void testAlgoNameValidation() throws Exception {
+        try {
+            new IpSecAlgorithm("rot13", Arrays.copyOf(KEY_MATERIAL, 128 / 8));
+            fail("Invalid algorithm name not validated");
+        } catch (IllegalArgumentException pass) {
+        }
+    }
+
+    @Test
+    public void testParcelUnparcel() throws Exception {
+        IpSecAlgorithm init =
+                new IpSecAlgorithm(
+                        IpSecAlgorithm.AUTH_HMAC_SHA512, Arrays.copyOf(KEY_MATERIAL, 512 / 8), 256);
+
+        Parcel p = Parcel.obtain();
+        p.setDataPosition(0);
+        init.writeToParcel(p, 0);
+
+        p.setDataPosition(0);
+        IpSecAlgorithm fin = IpSecAlgorithm.CREATOR.createFromParcel(p);
+        assertTrue("Parcel/Unparcel failed!", IpSecAlgorithm.equals(init, fin));
+        p.recycle();
+    }
+}

tests/net/java/android/net/IpSecConfigTest.java

@@ -71,7 +71,7 @@ public class IpSecConfigTest {
         c.setAuthentication(
                 IpSecTransform.DIRECTION_OUT,
                 new IpSecAlgorithm(
-                        IpSecAlgorithm.AUTH_HMAC_SHA1,
+                        IpSecAlgorithm.AUTH_HMAC_MD5,
                         new byte[] {1, 2, 3, 4, 5, 6, 7, 8, 9, 0xA, 0xB, 0xC, 0xD, 0xE, 0xF, 0}));
         c.setSpiResourceId(IpSecTransform.DIRECTION_OUT, 1984);
         c.setEncryption(
@@ -82,7 +82,7 @@ public class IpSecConfigTest {
         c.setAuthentication(
                 IpSecTransform.DIRECTION_IN,
                 new IpSecAlgorithm(
-                        IpSecAlgorithm.AUTH_HMAC_SHA1,
+                        IpSecAlgorithm.AUTH_HMAC_MD5,
                         new byte[] {1, 2, 3, 4, 5, 6, 7, 8, 9, 0xA, 0xB, 0xC, 0xD, 0xE, 0xF, 1}));
         c.setSpiResourceId(IpSecTransform.DIRECTION_IN, 99);
         assertParcelingIsLossless(c);