/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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 org.apache.harmony.security.tests.java.security;

import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.security.DigestException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.security.NoSuchProviderException;
import java.security.Provider;
import java.security.Security;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;

import dalvik.system.VMRuntime;
import libcore.junit.junit3.TestCaseWithRules;
import libcore.junit.util.EnableDeprecatedBouncyCastleAlgorithmsRule;
import org.junit.Rule;
import org.junit.rules.TestRule;
import sun.security.jca.Providers;

public class MessageDigest2Test extends TestCaseWithRules {

    // Allow access to deprecated BC algorithms in this test, so we can ensure they
    // continue to work
    @Rule
    public TestRule enableDeprecatedBCAlgorithmsRule =
            EnableDeprecatedBouncyCastleAlgorithmsRule.getInstance();

    private static final String MESSAGEDIGEST_ID = "MessageDigest.";

    private Map<Provider, List<String>> digestAlgs = new HashMap<Provider, List<String>>();

    private static final byte[] AR1 = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 };

    private static final byte[] AR2 = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 0 };

    private static final String MESSAGE = "abc";

    private static final byte[] MESSAGE_DIGEST = { -87, -103, 62, 54, 71, 6,
            -127, 106, -70, 62, 37, 113, 120, 80, -62, 108, -100, -48, -40,
            -99, };

    private static final byte[] MESSAGE_DIGEST_63_As = { 3, -16, -97, 91, 21,
            -118, 122, -116, -38, -39, 32, -67, -36, 41, -72, 28, 24, -91, 81,
            -11, };

    private static final byte[] MESSAGE_DIGEST_64_As = { 0, -104, -70, -126,
            75, 92, 22, 66, 123, -41, -95, 18, 42, 90, 68, 42, 37, -20, 100,
            77, };

    private static final byte[] MESSAGE_DIGEST_65_As = { 17, 101, 83, 38, -57,
            8, -41, 3, 25, -66, 38, 16, -24, -91, 125, -102, 91, -107, -99, 59, };

    /**
     * java.security.MessageDigest#MessageDigest(java.lang.String)
     */
    public void test_constructor() {
        for (List<String> algorithms : digestAlgs.values()) {
            for (String algorithm : algorithms) {
                MessageDigestStub md = new MessageDigestStub(algorithm);
                assertEquals(algorithm, md.getAlgorithm());
                assertEquals(0, md.getDigestLength());
                assertNull(md.getProvider());
            }
        }
    }

    /**
     * java.security.MessageDigest#clone()
     */
    public void test_clone() throws Exception {
        for (Entry<Provider, List<String>> e : digestAlgs.entrySet()) {
            for (String algorithm : e.getValue()) {
                MessageDigest d1 = MessageDigest.getInstance(algorithm, e.getKey().getName());
                for (byte b = 0; b < 84; b++) {
                    d1.update(b);
                }

                MessageDigest d2 = (MessageDigest) d1.clone();
                d1.update((byte) 1);
                d2.update((byte) 1);

                assertTrue("cloned hash differs from original for algorithm " + algorithm,
                           MessageDigest.isEqual(d1.digest(), d2.digest()));
            }
        }
    }

    private static final byte[] SHA_DATA_2 = { 70, -54, 124, 120, -29, 57, 56,
            119, -108, -54, -97, -76, -97, -50, -63, -73, 2, 85, -53, -79, };

    private void testSerializationSHA_DATA_2(MessageDigest sha) throws Exception {
        sha.reset();
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        DataOutputStream output = new DataOutputStream(out);

        // Made up data
        output.writeUTF("tests.api.java.security.MessageDigestTest$InitializerFieldsTest3");
        output.writeInt(0); // class modifiers
        output.writeUTF("java.io.Serializable"); // interfaces

        // Fields
        output.writeUTF("sub_toBeNotSerialized"); // name
        output.writeInt(9); // modifiers
        output.writeUTF("Ljava/lang/String;"); // signature

        output.writeUTF("sub_toBeNotSerialized2"); // name
        output.writeInt(9); // modifiers
        output.writeUTF("Ljava/lang/String;"); // signature

        output.writeUTF("sub_toBeSerialized"); // name
        output.writeInt(1); // modifiers
        output.writeUTF("Ljava/lang/String;"); // signature

        output.writeUTF("sub_toBeSerialized3"); // name
        output.writeInt(1); // modifiers
        output.writeUTF("Ljava/lang/String;"); // signature

        output.writeUTF("sub_toBeSerialized4"); // name
        output.writeInt(1); // modifiers
        output.writeUTF("Ljava/lang/String;"); // signature

        output.writeUTF("sub_toBeSerialized5"); // name
        output.writeInt(1); // modifiers
        output.writeUTF("Ljava/lang/String;"); // signature

        // clinit
        output.writeUTF("<clinit>"); // name
        output.writeInt(8); // modifiers
        output.writeUTF("()V"); // signature

        // constructors
        output.writeUTF("<init>"); // name
        output.writeInt(0); // modifiers
        output.writeUTF("()V"); // signature

        // methods
        output.writeUTF("equals"); // name
        output.writeInt(1); // modifiers
        output.writeUTF("(Ljava.lang.Object;)Z"); // signature

        output.flush();

        byte[] data = out.toByteArray();
        byte[] hash = sha.digest(data);
        assertTrue("SHA_DATA_2 NOT ok", Arrays.equals(hash, SHA_DATA_2));
    }

    private static final byte[] SHA_DATA_1 = { 90, 36, 111, 106, -32, 38, 4,
            126, 21, -51, 107, 45, -64, -68, -109, 112, -31, -46, 34, 115, };

    private void testSerializationSHA_DATA_1(MessageDigest sha) throws Exception {
        sha.reset();
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        DataOutputStream output = new DataOutputStream(out);

        // Made up data
        output.writeUTF("tests.api.java.security.MessageDigestTest$OptionalDataNotRead");
        // name
        output.writeInt(0); // class modifiers
        output.writeUTF("java.io.Serializable"); // interfaces

        // Fields
        output.writeUTF("class$0"); // name
        output.writeInt(8); // modifiers
        output.writeUTF("Ljava/lang/Class;"); // signature

        output.writeUTF("field1"); // name
        output.writeInt(2); // modifiers
        output.writeUTF("I"); // signature

        output.writeUTF("field2"); // name
        output.writeInt(2); // modifiers
        output.writeUTF("I"); // signature

        // clinit
        output.writeUTF("<clinit>"); // name
        output.writeInt(8); // modifiers
        output.writeUTF("()V"); // signature

        // constructors
        output.writeUTF("<init>"); // name
        output.writeInt(1); // modifiers
        output.writeUTF("()V"); // signature

        output.flush();
        byte[] data = out.toByteArray();
        byte[] hash = sha.digest(data);
        assertTrue("SHA_DATA_1 NOT ok", Arrays.equals(hash, SHA_DATA_1));
    }

    /**
     * java.security.MessageDigest#digest()
     */
    public void test_digest() throws Exception {
        MessageDigest sha = MessageDigest.getInstance("SHA");
        assertNotNull(sha);
        sha.update(MESSAGE.getBytes());
        byte[] digest = sha.digest();
        assertTrue("bug in SHA", MessageDigest.isEqual(digest, MESSAGE_DIGEST));

        sha.reset();
        for (int i = 0; i < 63; i++) {
            // just under buffer capacity
            sha.update((byte) 'a');
        }
        digest = sha.digest();
        assertTrue("bug in SHA", MessageDigest.isEqual(digest, MESSAGE_DIGEST_63_As));

        sha.reset();
        for (int i = 0; i < 64; i++) {
            // exact SHA buffer capacity
            sha.update((byte) 'a');
        }
        digest = sha.digest();
        assertTrue("bug in SHA", MessageDigest.isEqual(digest, MESSAGE_DIGEST_64_As));

        sha.reset();
        for (int i = 0; i < 65; i++) {
            // just above SHA buffer capacity
            sha.update((byte) 'a');
        }
        digest = sha.digest();
        assertTrue("bug in SHA", MessageDigest.isEqual(digest, MESSAGE_DIGEST_65_As));

        testSerializationSHA_DATA_1(sha);
        testSerializationSHA_DATA_2(sha);
    }

    /**
     * java.security.MessageDigest#digest(byte[])
     */
    public void test_digest$B() throws Exception {
        for (Entry<Provider, List<String>> e : digestAlgs.entrySet()) {
            for (String algorithm : e.getValue()) {
                MessageDigest digest = MessageDigest.getInstance(algorithm, e.getKey().getName());
                assertNotNull(digest);
                digest.digest(AR1);
            }
        }
    }

    /**
     * java.security.MessageDigest#digest(byte[], int, int)
     */
    public void test_digest$BII() throws Exception {
        for (Entry<Provider, List<String>> e : digestAlgs.entrySet()) {
            for (String algorithm : e.getValue()) {
                MessageDigest digest = MessageDigest.getInstance(algorithm, e.getKey().getName());
                assertNotNull(digest);
                int len = digest.getDigestLength();
                byte[] digestBytes = new byte[len];
                digest.digest(digestBytes, 0, digestBytes.length);
            }
            try {
                MessageDigest.getInstance("SHA").digest(new byte[] {}, Integer.MAX_VALUE, 755);
                fail();
            } catch (IllegalArgumentException expected) {
            }
        }
    }

    /**
     * java.security.MessageDigest#update(byte[], int, int)
     */
    public void test_update$BII() throws Exception {
        try {
            MessageDigest.getInstance("SHA").update(new byte[] {},
                                                    Integer.MAX_VALUE, Integer.MAX_VALUE);
            fail();
        } catch (IllegalArgumentException expected) {
        }
    }

    /**
     * java.security.MessageDigest#getAlgorithm()
     */
    public void test_getAlgorithm() throws Exception {
        for (Entry<Provider, List<String>> e : digestAlgs.entrySet()) {
            for (String algorithm : e.getValue()) {
                MessageDigest md = MessageDigest.getInstance(algorithm, e.getKey().getName());
                assertEquals(algorithm, md.getAlgorithm());
            }
        }
    }

    /**
     * java.security.MessageDigest#getDigestLength()
     */
    public void test_getDigestLength() throws Exception {
        for (Entry<Provider, List<String>> e : digestAlgs.entrySet()) {
            for (String algorithm : e.getValue()) {
                MessageDigest md = MessageDigest.getInstance(algorithm, e.getKey().getName());
                assertTrue("length not ok", md.getDigestLength() > 0);
            }
        }
    }

    /**
     * java.security.MessageDigest#getInstance(java.lang.String)
     */
    public void test_getInstanceLjava_lang_String() throws Exception {
        for (Entry<Provider, List<String>> e : digestAlgs.entrySet()) {
            for (String algorithm : e.getValue()) {
                MessageDigest md = MessageDigest.getInstance(algorithm);
                assertNotNull(md);
            }
        }

        try {
            MessageDigest.getInstance("UnknownDigest");
            fail("expected NoSuchAlgorithmException");
        } catch (NoSuchAlgorithmException expected) {
        }
    }

    /**
     * java.security.MessageDigest#getInstance(java.lang.String,
     *        java.lang.String)
     */
    public void test_getInstanceLjava_lang_StringLjava_lang_String() throws Exception {
        for (Entry<Provider, List<String>> e : digestAlgs.entrySet()) {
            for (String algorithm : e.getValue()) {
                MessageDigest md = MessageDigest.getInstance(algorithm, e.getKey().getName());
                assertNotNull(md);
            }
        }

        for (List<String> algorithms : digestAlgs.values()) {
            for (String algorithm : algorithms) {
                try {
                    MessageDigest.getInstance(algorithm, "UnknownProvider");
                    fail("expected NoSuchProviderException");
                } catch (NoSuchProviderException expected) {
                }
            }
        }

        for (Provider provider : digestAlgs.keySet()) {
            try {
                MessageDigest.getInstance("UnknownDigest", provider.getName());
                fail("expected NoSuchAlgorithmException");
            } catch (NoSuchAlgorithmException expected) {
            }
        }

        for (Provider provider : digestAlgs.keySet()) {
            try {
                MessageDigest.getInstance(null, provider.getName());
                fail("expected NullPointerException");
            } catch (NullPointerException expected) {
            }
        }

        try {
            MessageDigest.getInstance("AnyDigest", (String)null);
            fail("expected IllegalArgumentException");
        } catch (IllegalArgumentException expected) {
        }
    }

    /**
     * java.security.MessageDigest#getInstance(java.lang.String,
     *        java.security.Provider)
     */
    public void test_getInstanceLjava_lang_StringLjava_security_Provider() throws Exception {
        for (Entry<Provider, List<String>> e : digestAlgs.entrySet()) {
            for (String algorithm : e.getValue()) {
                MessageDigest md = MessageDigest.getInstance(algorithm, e.getKey().getName());
                assertNotNull(md);
            }
        }

        try {
            MessageDigest.getInstance(null, new TestProvider());
            fail("expected NullPointerException");
        } catch (NullPointerException expected) {
        }

        try {
            MessageDigest.getInstance("UnknownDigest", new TestProvider());
            fail("expected NoSuchAlgorithmException");
        } catch (NoSuchAlgorithmException expected) {
        }

        try {
            MessageDigest.getInstance("AnyDigest", (Provider)null);
            fail("expected IllegalArgumentException");
        } catch (IllegalArgumentException expected) {
        }
    }

    /**
     * java.security.MessageDigest#getProvider()
     */
    public void test_getProvider() throws Exception {
        for (Entry<Provider, List<String>> e : digestAlgs.entrySet()) {
            for (String algorithm : e.getValue()) {
                MessageDigest md = MessageDigest.getInstance(algorithm, e.getKey().getName());
                assertNotNull("provider is null", md.getProvider());
            }
        }
    }

    /**
     * java.security.MessageDigest#isEqual(byte[], byte[])
     */
    public void test_isEqual$B$B() {
        assertTrue("isEqual is not correct", MessageDigest.isEqual(AR1, AR2));
    }

    /**
     * java.security.MessageDigest#toString()
     */
    public void test_toString() throws Exception {
        String str = MessageDigest.getInstance("SHA").toString();
        assertNotNull("toString is null", str);
    }

    protected void setUp() throws Exception {
        super.setUp();
        Provider[] providers = Security.getProviders("MessageDigest.SHA");
        for (Provider provider : providers) {
            digestAlgs.put(provider, getDigestAlgorithms(provider));
        }
    }

    /*
     * Returns the digest algorithms that the given provider supports.
     */
    private List<String> getDigestAlgorithms(Provider provider) {
        if (provider == null) {
            fail("No digest algorithms were found");
        }

        List<String> algs = new ArrayList<String>();
        for (Object key : provider.keySet()) {
            String algorithm = (String) key;
            if (algorithm.startsWith(MESSAGEDIGEST_ID) && !algorithm.contains(" ")) {
                algs.add(algorithm.substring(MESSAGEDIGEST_ID.length()));
            }
        }

        if (algs.size() == 0) {
            fail("No digest algorithms were found");
        }
        return algs;
    }

    private class MessageDigestStub extends MessageDigest {
        public MessageDigestStub(String algorithm) {
            super(algorithm);
        }

        public byte[] engineDigest() {
            return null;
        }

        public void engineReset() {

        }

        public void engineUpdate(byte input) {

        }

        public void engineUpdate(byte[] input, int offset, int len) {

        }

    }

    private static class TestProvider extends Provider {

        protected TestProvider() {
            super("TestProvider", 1.0, "INFO");

        }

    }
}
