Reorganised Guice modules. Contribute entropy to pool on Linux/Android.

briar-tests/src/org/briarproject/system/LinuxSeedProviderTest.java

@@ -0,0 +1,77 @@
+package org.briarproject.system;
+
+import static org.briarproject.api.system.SeedProvider.SEED_BYTES;
+import static org.junit.Assert.assertArrayEquals;
+
+import java.io.File;
+import java.io.FileOutputStream;
+import java.util.HashSet;
+import java.util.Random;
+import java.util.Set;
+
+import org.briarproject.BriarTestCase;
+import org.briarproject.TestUtils;
+import org.briarproject.api.Bytes;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+
+public class LinuxSeedProviderTest extends BriarTestCase {
+
+	private final File testDir = TestUtils.getTestDirectory();
+
+	@Before
+	public void setUp() {
+		testDir.mkdirs();
+	}
+
+	@Test
+	public void testSeedAppearsSane() {
+		Set<Bytes> seeds = new HashSet<Bytes>();
+		LinuxSeedProvider p = new LinuxSeedProvider();
+		for(int i = 0; i < 1000; i++) {
+			byte[] seed = p.getSeed();
+			assertEquals(SEED_BYTES, seed.length);
+			assertTrue(seeds.add(new Bytes(seed)));
+		}
+	}
+
+	@Test
+	public void testEntropyIsWrittenToPool() throws Exception {
+		// Redirect the provider's entropy to a file
+		File urandom = new File(testDir, "urandom");
+		urandom.delete();
+		assertTrue(urandom.createNewFile());
+		assertEquals(0, urandom.length());
+		String path = urandom.getAbsolutePath();
+		LinuxSeedProvider p = new LinuxSeedProvider(path, "/dev/urandom");
+		p.getSeed();
+		// There should be 16 bytes from the clock, plus network interfaces
+		assertTrue(urandom.length() > 20);
+	}
+
+	@Test
+	public void testSeedIsReadFromPool() throws Exception {
+		// Generate a seed
+		byte[] seed = new byte[SEED_BYTES];
+		new Random().nextBytes(seed);
+		// Write the seed to a file
+		File urandom = new File(testDir, "urandom");
+		urandom.delete();
+		FileOutputStream out = new FileOutputStream(urandom);
+		out.write(seed);
+		out.flush();
+		out.close();
+		assertTrue(urandom.exists());
+		assertEquals(SEED_BYTES, urandom.length());
+		// Check that the provider reads the seed from the file
+		String path = urandom.getAbsolutePath();
+		LinuxSeedProvider p = new LinuxSeedProvider("/dev/urandom", path);
+		assertArrayEquals(seed, p.getSeed());
+	}
+
+	@After
+	public void tearDown() {
+		TestUtils.deleteTestDirectory(testDir);
+	}
+}