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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * particular file as subject to the "Classpath" exception as provided
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 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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package sun.security.ssl;

import java.security.*;
import java.util.*;
import sun.security.rsa.SunRsaSignEntries;
import static sun.security.util.SecurityConstants.PROVIDER_VER;
import static sun.security.provider.SunEntries.createAliases;

The JSSE provider.
The RSA implementation has been removed from JSSE, but we still need to
register the same algorithms for compatibility. We just point to the RSA
implementation in the SunRsaSign provider. This works because all classes
are in the bootclasspath and therefore loaded by the same classloader.
SunJSSE now supports an experimental FIPS compliant mode when used with an
appropriate FIPS certified crypto provider. In FIPS mode, we:
 . allow only TLS 1.0 or later
 . allow only FIPS approved ciphersuites
 . perform all crypto in the FIPS crypto provider
It is currently not possible to use both FIPS compliant SunJSSE and
standard JSSE at the same time because of the various static data structures
we use.
However, we do want to allow FIPS mode to be enabled at runtime and without
editing the java.security file. That means we need to allow
Security.removeProvider("SunJSSE") to work, which creates an instance of
this class in non-FIPS mode. That is why we delay the selection of the mode
as long as possible. This is until we open an SSL/TLS connection and the
data structures need to be initialized or until SunJSSE is initialized in
FIPS mode.
/**
 * The JSSE provider.
 *
 * The RSA implementation has been removed from JSSE, but we still need to
 * register the same algorithms for compatibility. We just point to the RSA
 * implementation in the SunRsaSign provider. This works because all classes
 * are in the bootclasspath and therefore loaded by the same classloader.
 *
 * SunJSSE now supports an experimental FIPS compliant mode when used with an
 * appropriate FIPS certified crypto provider. In FIPS mode, we:
 *  . allow only TLS 1.0 or later
 *  . allow only FIPS approved ciphersuites
 *  . perform all crypto in the FIPS crypto provider
 *
 * It is currently not possible to use both FIPS compliant SunJSSE and
 * standard JSSE at the same time because of the various static data structures
 * we use.
 *
 * However, we do want to allow FIPS mode to be enabled at runtime and without
 * editing the java.security file. That means we need to allow
 * Security.removeProvider("SunJSSE") to work, which creates an instance of
 * this class in non-FIPS mode. That is why we delay the selection of the mode
 * as long as possible. This is until we open an SSL/TLS connection and the
 * data structures need to be initialized or until SunJSSE is initialized in
 * FIPS mode.
 *
 */
public abstract class SunJSSE extends java.security.Provider {

    private static final long serialVersionUID = 3231825739635378733L;

    private static String info = "Sun JSSE provider" +
        "(PKCS12, SunX509/PKIX key/trust factories, " +
        "SSLv3/TLSv1/TLSv1.1/TLSv1.2/TLSv1.3/DTLSv1.0/DTLSv1.2)";

    private static String fipsInfo =
        "Sun JSSE provider (FIPS mode, crypto provider ";

    // tri-valued flag:
    // null  := no final decision made
    // false := data structures initialized in non-FIPS mode
    // true  := data structures initialized in FIPS mode
    private static Boolean fips;

    // the FIPS certificate crypto provider that we use to perform all crypto
    // operations. null in non-FIPS mode
    static java.security.Provider cryptoProvider;

    protected static synchronized boolean isFIPS() {
        if (fips == null) {
            fips = false;
        }
        return fips;
    }

    // ensure we can use FIPS mode using the specified crypto provider.
    // enable FIPS mode if not already enabled.
    private static synchronized void ensureFIPS(java.security.Provider p) {
        if (fips == null) {
            fips = true;
            cryptoProvider = p;
        } else {
            if (fips == false) {
                throw new ProviderException
                    ("SunJSSE already initialized in non-FIPS mode");
            }
            if (cryptoProvider != p) {
                throw new ProviderException
                    ("SunJSSE already initialized with FIPS crypto provider "
                    + cryptoProvider);
            }
        }
    }

    // standard constructor
    protected SunJSSE() {
        super("SunJSSE", PROVIDER_VER, info);
        subclassCheck();
        if (Boolean.TRUE.equals(fips)) {
            throw new ProviderException
                ("SunJSSE is already initialized in FIPS mode");
        }
        registerAlgorithms(false);
    }

    // preferred constructor to enable FIPS mode at runtime
    protected SunJSSE(java.security.Provider cryptoProvider){
        this(checkNull(cryptoProvider), cryptoProvider.getName());
    }

    // constructor to enable FIPS mode from java.security file
    protected SunJSSE(String cryptoProvider){
        this(null, checkNull(cryptoProvider));
    }

    private static <T> T checkNull(T t) {
        if (t == null) {
            throw new ProviderException("cryptoProvider must not be null");
        }
        return t;
    }

    private SunJSSE(java.security.Provider cryptoProvider,
            String providerName) {
        super("SunJSSE", PROVIDER_VER, fipsInfo + providerName + ")");
        subclassCheck();
        if (cryptoProvider == null) {
            // Calling Security.getProvider() will cause other providers to be
            // loaded. That is not good but unavoidable here.
            cryptoProvider = Security.getProvider(providerName);
            if (cryptoProvider == null) {
                throw new ProviderException
                    ("Crypto provider not installed: " + providerName);
            }
        }
        ensureFIPS(cryptoProvider);
        registerAlgorithms(true);
    }

    private void registerAlgorithms(final boolean isfips) {
        AccessController.doPrivileged(new PrivilegedAction<Object>() {
            @Override
            public Object run() {
                doRegister(isfips);
                return null;
            }
        });
    }

    private void ps(String type, String algo, String cn,
            List<String> aliases, HashMap<String, String> attrs) {
        putService(new Provider.Service(this, type, algo, cn, aliases, attrs));
    }

    private void doRegister(boolean isfips) {
        if (isfips == false) {
            Iterator<Provider.Service> rsaIter =
                new SunRsaSignEntries(this).iterator();
            while (rsaIter.hasNext()) {
                putService(rsaIter.next());
            }
        }
        ps("Signature", "MD5andSHA1withRSA",
            "sun.security.ssl.RSASignature", null, null);

        ps("KeyManagerFactory", "SunX509",
            "sun.security.ssl.KeyManagerFactoryImpl$SunX509", null, null);
        ps("KeyManagerFactory", "NewSunX509",
            "sun.security.ssl.KeyManagerFactoryImpl$X509",
            createAliases("PKIX"), null);

        ps("TrustManagerFactory", "SunX509",
            "sun.security.ssl.TrustManagerFactoryImpl$SimpleFactory", null, null);
        ps("TrustManagerFactory", "PKIX",
            "sun.security.ssl.TrustManagerFactoryImpl$PKIXFactory",
            createAliases("SunPKIX", "X509", "X.509"), null);

        ps("SSLContext", "TLSv1",
            "sun.security.ssl.SSLContextImpl$TLS10Context",
            (isfips? null : createAliases("SSLv3")), null);
        ps("SSLContext", "TLSv1.1",
            "sun.security.ssl.SSLContextImpl$TLS11Context", null, null);
        ps("SSLContext", "TLSv1.2",
            "sun.security.ssl.SSLContextImpl$TLS12Context", null, null);
        ps("SSLContext", "TLSv1.3",
            "sun.security.ssl.SSLContextImpl$TLS13Context", null, null);
        ps("SSLContext", "TLS",
            "sun.security.ssl.SSLContextImpl$TLSContext",
            (isfips? null : createAliases("SSL")), null);

        ps("SSLContext", "DTLSv1.0",
            "sun.security.ssl.SSLContextImpl$DTLS10Context", null, null);
        ps("SSLContext", "DTLSv1.2",
            "sun.security.ssl.SSLContextImpl$DTLS12Context", null, null);
        ps("SSLContext", "DTLS",
            "sun.security.ssl.SSLContextImpl$DTLSContext", null, null);

        ps("SSLContext", "Default",
            "sun.security.ssl.SSLContextImpl$DefaultSSLContext", null, null);

        /*
         * KeyStore
         */
        ps("KeyStore", "PKCS12",
            "sun.security.pkcs12.PKCS12KeyStore", null, null);
    }

    // com.sun.net.ssl.internal.ssl.Provider has been deprecated since JDK 9
    @SuppressWarnings("deprecation")
    private void subclassCheck() {
        if (getClass() != com.sun.net.ssl.internal.ssl.Provider.class) {
            throw new AssertionError("Illegal subclass: " + getClass());
        }
    }

    @Override
    @SuppressWarnings("deprecation")
    protected final void finalize() throws Throwable {
        // empty
        super.finalize();
    }

}