Merge "Revert "Create new ID3v2 metadata test""
diff --git a/tests/tests/permission/src/android/permission/cts/FileSystemPermissionTest.java b/tests/tests/permission/src/android/permission/cts/FileSystemPermissionTest.java
index eaea367..ab6ff46 100644
--- a/tests/tests/permission/src/android/permission/cts/FileSystemPermissionTest.java
+++ b/tests/tests/permission/src/android/permission/cts/FileSystemPermissionTest.java
@@ -739,7 +739,6 @@
                 new File("/dev/felica_uicc"),
                 new File("/dev/full"),
                 new File("/dev/genlock"),    // b/9035217
-                new File("/dev/hw_random"),  // b/9191279
                 new File("/dev/ion"),
                 new File("/dev/kgsl-3d0"),   // b/9035217
                 new File("/dev/log/events"), // b/9035217
@@ -797,6 +796,24 @@
                 (status.mode & 0666) == 0666);
     }
 
+    public void testDevHwRandomLockedDown() throws Exception {
+        File f = new File("/dev/hw_random");
+        if (!f.exists()) {
+            // HW RNG is not required to be exposed on all devices.
+            return;
+        }
+
+        FileUtils.FileStatus status = new FileUtils.FileStatus();
+        assertTrue(FileUtils.getFileStatus(f.getCanonicalPath(), status, false));
+        assertTrue(
+                f + " has wrong file mode: 0"
+                        + Integer.toOctalString(status.mode),
+                (status.mode & 0777) == 0440);
+
+        assertFileOwnedBy(f, "root");
+        assertFileOwnedByGroup(f, "system");
+    }
+
     /**
      * Test that the /system/bin/run-as command has setuid and setgid
      * attributes set on the file.  If these calls fail, debugger
diff --git a/tests/tests/security/src/android/security/cts/HwRngTest.java b/tests/tests/security/src/android/security/cts/HwRngTest.java
new file mode 100644
index 0000000..3dc11af
--- /dev/null
+++ b/tests/tests/security/src/android/security/cts/HwRngTest.java
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2013 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.security.cts;
+
+import junit.framework.TestCase;
+
+import java.io.BufferedReader;
+import java.io.ByteArrayOutputStream;
+import java.io.Closeable;
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Tests for hardware random number generator device {@code /dev/hw_random}.
+ */
+public class HwRngTest extends TestCase {
+
+    // The block of constants below is from hw_random framework documentation and source code:
+    // see https://www.kernel.org/doc/Documentation/hw_random.txt.
+    private static final File DEV_HW_RANDOM = new File("/dev/hw_random");
+    private static final File SYSFS_HW_RANDOM = new File("/sys/class/misc/hw_random");
+    private static final String HWRNG_DRIVER_NAME = "hwrng";
+    private static final int HWRNG_DRIVER_MAJOR = 10;
+    private static final int HWRNG_DRIVER_MINOR = 183;
+
+    /**
+     * Asserts that the {@code /dev/hw_random} device is configured in an acceptable way or is not
+     * present at all.
+     */
+    public void testConfigurationIfFilePresent() throws Exception {
+        if (!DEV_HW_RANDOM.exists()) {
+            // The device is not present
+            return;
+        }
+
+        // Sanity check based on https://www.kernel.org/doc/Documentation/hw_random.txt.
+
+        // In short, assert that:
+        // 1. hwrng kernel driver is using MAJOR 10 and MINOR 183,
+        // 2. a driver is selected in the hrwng framework, and
+        // 3. /dev/hw_random references a character device with the above MAJOR and MINOR.
+
+        // 1. Assert that the hwrng driver is using MAJOR 10 and MINOR 183.
+        //    We achieve this by inspecting /sys/class/misc/hw_random/dev and uevent.
+        assertTrue(SYSFS_HW_RANDOM + " not found", SYSFS_HW_RANDOM.isDirectory());
+        assertEquals(
+                "Driver major:minor",
+                HWRNG_DRIVER_MAJOR + ":" + HWRNG_DRIVER_MINOR,
+                readyFullyAsciiFile(new File(SYSFS_HW_RANDOM, "dev")).trim());
+
+        Map<String, String> ueventVars = parseUeventFile(new File(SYSFS_HW_RANDOM, "uevent"));
+        assertEquals("uevent MAJOR", String.valueOf(HWRNG_DRIVER_MAJOR), ueventVars.get("MAJOR"));
+        assertEquals("uevent MINOR", String.valueOf(HWRNG_DRIVER_MINOR), ueventVars.get("MINOR"));
+        assertEquals("uevent DEVNAME", HWRNG_DRIVER_NAME, ueventVars.get("DEVNAME"));
+
+        // 2. Assert that a driver is selected in the hrwng framework.
+        //    We achieve this by inspecting /sys/class/misc/hw_random/rng_current.
+        File rngCurrentFile = new File(SYSFS_HW_RANDOM, "rng_current");
+        String rngCurrent = readyFullyAsciiFile(rngCurrentFile);
+        assertFalse(
+                "No driver selected according to " + rngCurrentFile,
+                rngCurrent.trim().isEmpty());
+
+        // 3. Assert that /dev/hw_random references a character device with the above MAJOR+MINOR.
+        assertEquals(
+                DEV_HW_RANDOM + " major",
+                HWRNG_DRIVER_MAJOR,
+                LinuxRngTest.getCharDeviceMajor(DEV_HW_RANDOM.getCanonicalPath()));
+        assertEquals(
+                DEV_HW_RANDOM + " minor",
+                HWRNG_DRIVER_MINOR,
+                LinuxRngTest.getCharDeviceMinor(DEV_HW_RANDOM.getCanonicalPath()));
+    }
+
+    private static String readyFullyAsciiFile(File file) throws IOException {
+        InputStream in = null;
+        try {
+            in = new FileInputStream(file);
+            return new String(readyFully(in), "US-ASCII");
+        } finally {
+            closeSilently(in);
+        }
+    }
+
+    private static byte[] readyFully(InputStream in) throws IOException {
+        ByteArrayOutputStream result = new ByteArrayOutputStream();
+        byte[] buffer = new byte[16 * 1024];
+        int chunkSize;
+        while ((chunkSize = in.read(buffer)) != -1) {
+            result.write(buffer, 0, chunkSize);
+        }
+        return result.toByteArray();
+    }
+
+    private static Map<String, String> parseUeventFile(File file) throws IOException {
+        // The format of the file is line-oriented.
+        // Each variable takes up one line.
+        // The typical format of a variable is KEY=VALUE
+
+        Map<String, String> result = new HashMap<String, String>();
+        BufferedReader in = null;
+        try {
+            in = new BufferedReader(new InputStreamReader(new FileInputStream(file), "US-ASCII"));
+            String line;
+            while ((line = in.readLine()) != null) {
+                if (line.trim().length() == 0) {
+                    // Ignore empty lines
+                    continue;
+                }
+
+                String key;
+                String value;
+                int delimiterIndex = line.indexOf('=');
+                if (delimiterIndex != -1) {
+                    key = line.substring(0, delimiterIndex);
+                    value = line.substring(delimiterIndex + 1);
+                } else {
+                    key = line;
+                    value = "";
+                }
+
+                if (result.containsKey(key)) {
+                    throw new IllegalArgumentException("Multiple values for key: " + key);
+                }
+                result.put(key, value);
+            }
+            return result;
+        } finally {
+            closeSilently(in);
+        }
+    }
+
+    private static void closeSilently(Closeable in) {
+        if (in != null) {
+            try {
+                in.close();
+            } catch (IOException ignored) {}
+        }
+    }
+}
\ No newline at end of file