/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

package sun.security.ssl;

import java.util.HashSet;

import java.util.Set;

import sun.security.ssl.CipherSuite.HashAlg;

import sun.security.ssl.CipherSuite.KeyExchange;

import static sun.security.ssl.CipherSuite.KeyExchange.*;

import sun.security.ssl.CipherSuite.MacAlg;

import static sun.security.ssl.SSLCipher.*;

import sun.security.util.AlgorithmDecomposer;

/**

 * The class decomposes standard SSL/TLS cipher suites into sub-elements.

 */

class SSLAlgorithmDecomposer extends AlgorithmDecomposer {

    // indicates that only certification path algorithms need to be used

    private final boolean onlyX509;

    SSLAlgorithmDecomposer(boolean onlyX509) {

        this.onlyX509 = onlyX509;

    }

    SSLAlgorithmDecomposer() {

        this(false);

    }

    private Set<String> decomposes(CipherSuite.KeyExchange keyExchange) {

        Set<String> components = new HashSet<>();

        switch (keyExchange) {

            case K_NULL:

                if (!onlyX509) {

                    components.add("K_NULL");

                }

                break;

            case K_RSA:

                components.add("RSA");

                break;

            case K_RSA_EXPORT:

                components.add("RSA");

                components.add("RSA_EXPORT");

                break;

            case K_DH_RSA:

                components.add("RSA");

                components.add("DH");

                components.add("DiffieHellman");

                components.add("DH_RSA");

                break;

            case K_DH_DSS:

                components.add("DSA");

                components.add("DSS");

                components.add("DH");

                components.add("DiffieHellman");

                components.add("DH_DSS");

                break;

            case K_DHE_DSS:

                components.add("DSA");

                components.add("DSS");

                components.add("DH");

                components.add("DHE");

                components.add("DiffieHellman");

                components.add("DHE_DSS");

                break;

            case K_DHE_RSA:

                components.add("RSA");

                components.add("DH");

                components.add("DHE");

                components.add("DiffieHellman");

                components.add("DHE_RSA");

                break;

            case K_DH_ANON:

                if (!onlyX509) {

                    components.add("ANON");

                    components.add("DH");

                    components.add("DiffieHellman");

                    components.add("DH_ANON");

                }

                break;

            case K_ECDH_ECDSA:

                components.add("ECDH");

                components.add("ECDSA");

                components.add("ECDH_ECDSA");

                break;

            case K_ECDH_RSA:

                components.add("ECDH");

                components.add("RSA");

                components.add("ECDH_RSA");

                break;

            case K_ECDHE_ECDSA:

                components.add("ECDHE");

                components.add("ECDSA");

                components.add("ECDHE_ECDSA");

                break;

            case K_ECDHE_RSA:

                components.add("ECDHE");

                components.add("RSA");

                components.add("ECDHE_RSA");

                break;

            case K_ECDH_ANON:

                if (!onlyX509) {

                    components.add("ECDH");

                    components.add("ANON");

                    components.add("ECDH_ANON");

                }

                break;

            default:

                // otherwise ignore

            }

        return components;

    }

    private Set<String> decomposes(SSLCipher bulkCipher) {

        Set<String> components = new HashSet<>();

        if (bulkCipher.transformation != null) {

            components.addAll(super.decompose(bulkCipher.transformation));

        }

        switch (bulkCipher) {

            case B_NULL:

                components.add("C_NULL");

                break;

            case B_RC2_40:

                components.add("RC2_CBC_40");

                break;

            case B_RC4_40:

                components.add("RC4_40");

                break;

            case B_RC4_128:

                components.add("RC4_128");

                break;

            case B_DES_40:

                components.add("DES40_CBC");

                components.add("DES_CBC_40");

                break;

            case B_DES:

                components.add("DES_CBC");

                break;

            case B_3DES:

                components.add("3DES_EDE_CBC");

                break;

            case B_AES_128:

                components.add("AES_128_CBC");

                break;

            case B_AES_256:

                components.add("AES_256_CBC");

                break;

            case B_AES_128_GCM:

                components.add("AES_128_GCM");

                break;

            case B_AES_256_GCM:

                components.add("AES_256_GCM");

                break;

        }

        return components;

    }

    private Set<String> decomposes(CipherSuite.MacAlg macAlg,

            SSLCipher cipher) {

        Set<String> components = new HashSet<>();

        if (macAlg == CipherSuite.MacAlg.M_NULL

                && cipher.cipherType != CipherType.AEAD_CIPHER) {

            components.add("M_NULL");

        } else if (macAlg == CipherSuite.MacAlg.M_MD5) {

            components.add("MD5");

            components.add("HmacMD5");

        } else if (macAlg == CipherSuite.MacAlg.M_SHA) {

            components.add("SHA1");

            components.add("SHA-1");

            components.add("HmacSHA1");

        } else if (macAlg == CipherSuite.MacAlg.M_SHA256) {

            components.add("SHA256");

            components.add("SHA-256");

            components.add("HmacSHA256");

        } else if (macAlg == CipherSuite.MacAlg.M_SHA384) {

            components.add("SHA384");

            components.add("SHA-384");

            components.add("HmacSHA384");

        }

        return components;

    }

    private Set<String> decomposes(CipherSuite.HashAlg hashAlg) {

        Set<String> components = new HashSet<>();

        if (hashAlg == CipherSuite.HashAlg.H_SHA256) {

            components.add("SHA256");

            components.add("SHA-256");

            components.add("HmacSHA256");

        } else if (hashAlg == CipherSuite.HashAlg.H_SHA384) {

            components.add("SHA384");

            components.add("SHA-384");

            components.add("HmacSHA384");

        }

        return components;

    }

    private Set<String> decompose(KeyExchange keyExchange,

            SSLCipher cipher,

            MacAlg macAlg,

            HashAlg hashAlg) {

        Set<String> components = new HashSet<>();

        if (keyExchange != null) {

            components.addAll(decomposes(keyExchange));

        }

        if (onlyX509) {

            // Certification path algorithm constraints do not apply

            // to cipher and macAlg.

            return components;

        }

        if (cipher != null) {

            components.addAll(decomposes(cipher));

        }

        if (macAlg != null) {

            components.addAll(decomposes(macAlg, cipher));

        }

        if (hashAlg != null) {

            components.addAll(decomposes(hashAlg));

        }

        return components;

    }

    @Override

    public Set<String> decompose(String algorithm) {

        if (algorithm.startsWith("SSL_") || algorithm.startsWith("TLS_")) {

            CipherSuite cipherSuite = null;

            try {

                cipherSuite = CipherSuite.nameOf(algorithm);

            } catch (IllegalArgumentException iae) {

                // ignore: unknown or unsupported ciphersuite

            }

                return decompose(cipherSuite.keyExchange,

                        cipherSuite.bulkCipher,

                        cipherSuite.macAlg,

                        cipherSuite.hashAlg);

            }

        }

        return super.decompose(algorithm);

    }

}