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Java example source code file (Secmod.java)

This example Java source code file (Secmod.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

bytes, ck_attribute, file, fips, ioexception, keystore, list, module, nss, pkcs11exception, providerexception, secmod, security, string, trustattributes, util

The Secmod.java Java example source code

/*
 * Copyright (c) 2005, 2013, Oracle and/or its affiliates. All rights reserved.
 * 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.pkcs11;

import java.io.*;
import java.util.*;

import java.security.*;
import java.security.KeyStore.*;
import java.security.cert.X509Certificate;

import sun.security.pkcs11.wrapper.*;
import static sun.security.pkcs11.wrapper.PKCS11Constants.*;


/**
 * The Secmod class defines the interface to the native NSS
 * library and the configuration information it stores in its
 * secmod.db file.
 *
 * <p>Example code:
 * <pre>
 *   Secmod secmod = Secmod.getInstance();
 *   if (secmod.isInitialized() == false) {
 *       secmod.initialize("/home/myself/.mozilla", "/usr/sfw/lib/mozilla");
 *   }
 *
 *   Provider p = secmod.getModule(ModuleType.KEYSTORE).getProvider();
 *   KeyStore ks = KeyStore.getInstance("PKCS11", p);
 *   ks.load(null, password);
 * </pre>
 *
 * @since   1.6
 * @author  Andreas Sterbenz
 */
public final class Secmod {

    private final static boolean DEBUG = false;

    private final static Secmod INSTANCE;

    static {
        sun.security.pkcs11.wrapper.PKCS11.loadNative();
        INSTANCE = new Secmod();
    }

    private final static String NSS_LIB_NAME = "nss3";

    private final static String SOFTTOKEN_LIB_NAME = "softokn3";

    private final static String TRUST_LIB_NAME = "nssckbi";

    // handle to be passed to the native code, 0 means not initialized
    private long nssHandle;

    // whether this is a supported version of NSS
    private boolean supported;

    // list of the modules
    private List<Module> modules;

    private String configDir;

    private String nssLibDir;

    private Secmod() {
        // empty
    }

    /**
     * Return the singleton Secmod instance.
     */
    public static Secmod getInstance() {
        return INSTANCE;
    }

    private boolean isLoaded() {
        if (nssHandle == 0) {
            nssHandle = nssGetLibraryHandle(System.mapLibraryName(NSS_LIB_NAME));
            if (nssHandle != 0) {
                fetchVersions();
            }
        }
        return (nssHandle != 0);
    }

    private void fetchVersions() {
        supported = nssVersionCheck(nssHandle, "3.7");
    }

    /**
     * Test whether this Secmod has been initialized. Returns true
     * if NSS has been initialized using either the initialize() method
     * or by directly calling the native NSS APIs. The latter may be
     * the case if the current process contains components that use
     * NSS directly.
     *
     * @throws IOException if an incompatible version of NSS
     *   has been loaded
     */
    public synchronized boolean isInitialized() throws IOException {
        // NSS does not allow us to check if it is initialized already
        // assume that if it is loaded it is also initialized
        if (isLoaded() == false) {
            return false;
        }
        if (supported == false) {
            throw new IOException
                ("An incompatible version of NSS is already loaded, "
                + "3.7 or later required");
        }
        return true;
    }

    String getConfigDir() {
        return configDir;
    }

    String getLibDir() {
        return nssLibDir;
    }

    /**
     * Initialize this Secmod.
     *
     * @param configDir the directory containing the NSS configuration
     *   files such as secmod.db
     * @param nssLibDir the directory containing the NSS libraries
     *   (libnss3.so or nss3.dll) or null if the library is on
     *   the system default shared library path
     *
     * @throws IOException if NSS has already been initialized,
     *   the specified directories are invalid, or initialization
     *   fails for any other reason
     */
    public void initialize(String configDir, String nssLibDir)
            throws IOException {
        initialize(DbMode.READ_WRITE, configDir, nssLibDir, false);
    }

    public void initialize(DbMode dbMode, String configDir, String nssLibDir)
            throws IOException {
        initialize(dbMode, configDir, nssLibDir, false);
    }

    public synchronized void initialize(DbMode dbMode, String configDir,
        String nssLibDir, boolean nssOptimizeSpace) throws IOException {

        if (isInitialized()) {
            throw new IOException("NSS is already initialized");
        }

        if (dbMode == null) {
            throw new NullPointerException();
        }
        if ((dbMode != DbMode.NO_DB) && (configDir == null)) {
            throw new NullPointerException();
        }
        String platformLibName = System.mapLibraryName("nss3");
        String platformPath;
        if (nssLibDir == null) {
            platformPath = platformLibName;
        } else {
            File base = new File(nssLibDir);
            if (base.isDirectory() == false) {
                throw new IOException("nssLibDir must be a directory:" + nssLibDir);
            }
            File platformFile = new File(base, platformLibName);
            if (platformFile.isFile() == false) {
                throw new FileNotFoundException(platformFile.getPath());
            }
            platformPath = platformFile.getPath();
        }

        if (configDir != null) {
            File configBase = new File(configDir);
            if (configBase.isDirectory() == false ) {
                throw new IOException("configDir must be a directory: " + configDir);
            }
            File secmodFile = new File(configBase, "secmod.db");
            if (secmodFile.isFile() == false) {
                throw new FileNotFoundException(secmodFile.getPath());
            }
        }

        if (DEBUG) System.out.println("lib: " + platformPath);
        nssHandle = nssLoadLibrary(platformPath);
        if (DEBUG) System.out.println("handle: " + nssHandle);
        fetchVersions();
        if (supported == false) {
            throw new IOException
                ("The specified version of NSS is incompatible, "
                + "3.7 or later required");
        }

        if (DEBUG) System.out.println("dir: " + configDir);
        boolean initok = nssInitialize(dbMode.functionName, nssHandle,
            configDir, nssOptimizeSpace);
        if (DEBUG) System.out.println("init: " + initok);
        if (initok == false) {
            throw new IOException("NSS initialization failed");
        }

        this.configDir = configDir;
        this.nssLibDir = nssLibDir;
    }

    /**
     * Return an immutable list of all available modules.
     *
     * @throws IllegalStateException if this Secmod is misconfigured
     *   or not initialized
     */
    public synchronized List<Module> getModules() {
        try {
            if (isInitialized() == false) {
                throw new IllegalStateException("NSS not initialized");
            }
        } catch (IOException e) {
            // IOException if misconfigured
            throw new IllegalStateException(e);
        }
        if (modules == null) {
            @SuppressWarnings("unchecked")
            List<Module> modules = (List)nssGetModuleList(nssHandle,
                nssLibDir);
            this.modules = Collections.unmodifiableList(modules);
        }
        return modules;
    }

    private static byte[] getDigest(X509Certificate cert, String algorithm) {
        try {
            MessageDigest md = MessageDigest.getInstance(algorithm);
            return md.digest(cert.getEncoded());
        } catch (GeneralSecurityException e) {
            throw new ProviderException(e);
        }
    }

    boolean isTrusted(X509Certificate cert, TrustType trustType) {
        Bytes bytes = new Bytes(getDigest(cert, "SHA-1"));
        TrustAttributes attr = getModuleTrust(ModuleType.KEYSTORE, bytes);
        if (attr == null) {
            attr = getModuleTrust(ModuleType.FIPS, bytes);
            if (attr == null) {
                attr = getModuleTrust(ModuleType.TRUSTANCHOR, bytes);
            }
        }
        return (attr == null) ? false : attr.isTrusted(trustType);
    }

    private TrustAttributes getModuleTrust(ModuleType type, Bytes bytes) {
        Module module = getModule(type);
        TrustAttributes t = (module == null) ? null : module.getTrust(bytes);
        return t;
    }

    /**
     * Constants describing the different types of NSS modules.
     * For this API, NSS modules are classified as either one
     * of the internal modules delivered as part of NSS or
     * as an external module provided by a 3rd party.
     */
    public static enum ModuleType {
        /**
         * The NSS Softtoken crypto module. This is the first
         * slot of the softtoken object.
         * This module provides
         * implementations for cryptographic algorithms but no KeyStore.
         */
        CRYPTO,
        /**
         * The NSS Softtoken KeyStore module. This is the second
         * slot of the softtoken object.
         * This module provides
         * implementations for cryptographic algorithms (after login)
         * and the KeyStore.
         */
        KEYSTORE,
        /**
         * The NSS Softtoken module in FIPS mode. Note that in FIPS mode the
         * softtoken presents only one slot, not separate CRYPTO and KEYSTORE
         * slots as in non-FIPS mode.
         */
        FIPS,
        /**
         * The NSS builtin trust anchor module. This is the
         * NSSCKBI object. It provides no crypto functions.
         */
        TRUSTANCHOR,
        /**
         * An external module.
         */
        EXTERNAL,
    }

    /**
     * Returns the first module of the specified type. If no such
     * module exists, this method returns null.
     *
     * @throws IllegalStateException if this Secmod is misconfigured
     *   or not initialized
     */
    public Module getModule(ModuleType type) {
        for (Module module : getModules()) {
            if (module.getType() == type) {
                return module;
            }
        }
        return null;
    }

    static final String TEMPLATE_EXTERNAL =
        "library = %s\n"
        + "name = \"%s\"\n"
        + "slotListIndex = %d\n";

    static final String TEMPLATE_TRUSTANCHOR =
        "library = %s\n"
        + "name = \"NSS Trust Anchors\"\n"
        + "slotListIndex = 0\n"
        + "enabledMechanisms = { KeyStore }\n"
        + "nssUseSecmodTrust = true\n";

    static final String TEMPLATE_CRYPTO =
        "library = %s\n"
        + "name = \"NSS SoftToken Crypto\"\n"
        + "slotListIndex = 0\n"
        + "disabledMechanisms = { KeyStore }\n";

    static final String TEMPLATE_KEYSTORE =
        "library = %s\n"
        + "name = \"NSS SoftToken KeyStore\"\n"
        + "slotListIndex = 1\n"
        + "nssUseSecmodTrust = true\n";

    static final String TEMPLATE_FIPS =
        "library = %s\n"
        + "name = \"NSS FIPS SoftToken\"\n"
        + "slotListIndex = 0\n"
        + "nssUseSecmodTrust = true\n";

    /**
     * A representation of one PKCS#11 slot in a PKCS#11 module.
     */
    public static final class Module {
        // path of the native library
        final String libraryName;
        // descriptive name used by NSS
        final String commonName;
        final int slot;
        final ModuleType type;

        private String config;
        private SunPKCS11 provider;

        // trust attributes. Used for the KEYSTORE and TRUSTANCHOR modules only
        private Map<Bytes,TrustAttributes> trust;

        Module(String libraryDir, String libraryName, String commonName,
                boolean fips, int slot) {
            ModuleType type;

            if ((libraryName == null) || (libraryName.length() == 0)) {
                // must be softtoken
                libraryName = System.mapLibraryName(SOFTTOKEN_LIB_NAME);
                if (fips == false) {
                    type = (slot == 0) ? ModuleType.CRYPTO : ModuleType.KEYSTORE;
                } else {
                    type = ModuleType.FIPS;
                    if (slot != 0) {
                        throw new RuntimeException
                            ("Slot index should be 0 for FIPS slot");
                    }
                }
            } else {
                if (libraryName.endsWith(System.mapLibraryName(TRUST_LIB_NAME))
                        || commonName.equals("Builtin Roots Module")) {
                    type = ModuleType.TRUSTANCHOR;
                } else {
                    type = ModuleType.EXTERNAL;
                }
                if (fips) {
                    throw new RuntimeException("FIPS flag set for non-internal "
                        + "module: " + libraryName + ", " + commonName);
                }
            }
            // On Ubuntu the libsoftokn3 library is located in a subdirectory
            // of the system libraries directory. (Since Ubuntu 11.04.)
            File libraryFile = new File(libraryDir, libraryName);
            if (!libraryFile.isFile()) {
               File failover = new File(libraryDir, "nss/" + libraryName);
               if (failover.isFile()) {
                   libraryFile = failover;
               }
            }
            this.libraryName = libraryFile.getPath();
            this.commonName = commonName;
            this.slot = slot;
            this.type = type;
            initConfiguration();
        }

        private void initConfiguration() {
            switch (type) {
            case EXTERNAL:
                config = String.format(TEMPLATE_EXTERNAL, libraryName,
                                            commonName + " " + slot, slot);
                break;
            case CRYPTO:
                config = String.format(TEMPLATE_CRYPTO, libraryName);
                break;
            case KEYSTORE:
                config = String.format(TEMPLATE_KEYSTORE, libraryName);
                break;
            case FIPS:
                config = String.format(TEMPLATE_FIPS, libraryName);
                break;
            case TRUSTANCHOR:
                config = String.format(TEMPLATE_TRUSTANCHOR, libraryName);
                break;
            default:
                throw new RuntimeException("Unknown module type: " + type);
            }
        }

        /**
         * Get the configuration for this module. This is a string
         * in the SunPKCS11 configuration format. It can be
         * customized with additional options and then made
         * current using the setConfiguration() method.
         */
        @Deprecated
        public synchronized String getConfiguration() {
            return config;
        }

        /**
         * Set the configuration for this module.
         *
         * @throws IllegalStateException if the associated provider
         *   instance has already been created.
         */
        @Deprecated
        public synchronized void setConfiguration(String config) {
            if (provider != null) {
                throw new IllegalStateException("Provider instance already created");
            }
            this.config = config;
        }

        /**
         * Return the pathname of the native library that implements
         * this module. For example, /usr/lib/libpkcs11.so.
         */
        public String getLibraryName() {
            return libraryName;
        }

        /**
         * Returns the type of this module.
         */
        public ModuleType getType() {
            return type;
        }

        /**
         * Returns the provider instance that is associated with this
         * module. The first call to this method creates the provider
         * instance.
         */
        @Deprecated
        public synchronized Provider getProvider() {
            if (provider == null) {
                provider = newProvider();
            }
            return provider;
        }

        synchronized boolean hasInitializedProvider() {
            return provider != null;
        }

        void setProvider(SunPKCS11 p) {
            if (provider != null) {
                throw new ProviderException("Secmod provider already initialized");
            }
            provider = p;
        }

        private SunPKCS11 newProvider() {
            try {
                InputStream in = new ByteArrayInputStream(config.getBytes("UTF8"));
                return new SunPKCS11(in);
            } catch (Exception e) {
                // XXX
                throw new ProviderException(e);
            }
        }

        synchronized void setTrust(Token token, X509Certificate cert) {
            Bytes bytes = new Bytes(getDigest(cert, "SHA-1"));
            TrustAttributes attr = getTrust(bytes);
            if (attr == null) {
                attr = new TrustAttributes(token, cert, bytes, CKT_NETSCAPE_TRUSTED_DELEGATOR);
                trust.put(bytes, attr);
            } else {
                // does it already have the correct trust settings?
                if (attr.isTrusted(TrustType.ALL) == false) {
                    // XXX not yet implemented
                    throw new ProviderException("Cannot change existing trust attributes");
                }
            }
        }

        TrustAttributes getTrust(Bytes hash) {
            if (trust == null) {
                // If provider is not set, create a temporary provider to
                // retrieve the trust information. This can happen if we need
                // to get the trust information for the trustanchor module
                // because we need to look for user customized settings in the
                // keystore module (which may not have a provider created yet).
                // Creating a temporary provider and then dropping it on the
                // floor immediately is flawed, but it's the best we can do
                // for now.
                synchronized (this) {
                    SunPKCS11 p = provider;
                    if (p == null) {
                        p = newProvider();
                    }
                    try {
                        trust = Secmod.getTrust(p);
                    } catch (PKCS11Exception e) {
                        throw new RuntimeException(e);
                    }
                }
            }
            return trust.get(hash);
        }

        public String toString() {
            return
            commonName + " (" + type + ", " + libraryName + ", slot " + slot + ")";
        }

    }

    /**
     * Constants representing NSS trust categories.
     */
    public static enum TrustType {
        /** Trusted for all purposes */
        ALL,
        /** Trusted for SSL client authentication */
        CLIENT_AUTH,
        /** Trusted for SSL server authentication */
        SERVER_AUTH,
        /** Trusted for code signing */
        CODE_SIGNING,
        /** Trusted for email protection */
        EMAIL_PROTECTION,
    }

    public static enum DbMode {
        READ_WRITE("NSS_InitReadWrite"),
        READ_ONLY ("NSS_Init"),
        NO_DB     ("NSS_NoDB_Init");

        final String functionName;
        DbMode(String functionName) {
            this.functionName = functionName;
        }
    }

    /**
     * A LoadStoreParameter for use with the NSS Softtoken or
     * NSS TrustAnchor KeyStores.
     * <p>
     * It allows the set of trusted certificates that are returned by
     * the KeyStore to be specified.
     */
    public static final class KeyStoreLoadParameter implements LoadStoreParameter {
        final TrustType trustType;
        final ProtectionParameter protection;
        public KeyStoreLoadParameter(TrustType trustType, char[] password) {
            this(trustType, new PasswordProtection(password));

        }
        public KeyStoreLoadParameter(TrustType trustType, ProtectionParameter prot) {
            if (trustType == null) {
                throw new NullPointerException("trustType must not be null");
            }
            this.trustType = trustType;
            this.protection = prot;
        }
        public ProtectionParameter getProtectionParameter() {
            return protection;
        }
        public TrustType getTrustType() {
            return trustType;
        }
    }

    static class TrustAttributes {
        final long handle;
        final long clientAuth, serverAuth, codeSigning, emailProtection;
        final byte[] shaHash;
        TrustAttributes(Token token, X509Certificate cert, Bytes bytes, long trustValue) {
            Session session = null;
            try {
                session = token.getOpSession();
                // XXX use KeyStore TrustType settings to determine which
                // attributes to set
                CK_ATTRIBUTE[] attrs = new CK_ATTRIBUTE[] {
                    new CK_ATTRIBUTE(CKA_TOKEN, true),
                    new CK_ATTRIBUTE(CKA_CLASS, CKO_NETSCAPE_TRUST),
                    new CK_ATTRIBUTE(CKA_NETSCAPE_TRUST_SERVER_AUTH, trustValue),
                    new CK_ATTRIBUTE(CKA_NETSCAPE_TRUST_CODE_SIGNING, trustValue),
                    new CK_ATTRIBUTE(CKA_NETSCAPE_TRUST_EMAIL_PROTECTION, trustValue),
                    new CK_ATTRIBUTE(CKA_NETSCAPE_TRUST_CLIENT_AUTH, trustValue),
                    new CK_ATTRIBUTE(CKA_NETSCAPE_CERT_SHA1_HASH, bytes.b),
                    new CK_ATTRIBUTE(CKA_NETSCAPE_CERT_MD5_HASH, getDigest(cert, "MD5")),
                    new CK_ATTRIBUTE(CKA_ISSUER, cert.getIssuerX500Principal().getEncoded()),
                    new CK_ATTRIBUTE(CKA_SERIAL_NUMBER, cert.getSerialNumber().toByteArray()),
                    // XXX per PKCS#11 spec, the serial number should be in ASN.1
                };
                handle = token.p11.C_CreateObject(session.id(), attrs);
                shaHash = bytes.b;
                clientAuth = trustValue;
                serverAuth = trustValue;
                codeSigning = trustValue;
                emailProtection = trustValue;
            } catch (PKCS11Exception e) {
                throw new ProviderException("Could not create trust object", e);
            } finally {
                token.releaseSession(session);
            }
        }
        TrustAttributes(Token token, Session session, long handle)
                        throws PKCS11Exception {
            this.handle = handle;
            CK_ATTRIBUTE[] attrs = new CK_ATTRIBUTE[] {
                new CK_ATTRIBUTE(CKA_NETSCAPE_TRUST_SERVER_AUTH),
                new CK_ATTRIBUTE(CKA_NETSCAPE_TRUST_CODE_SIGNING),
                new CK_ATTRIBUTE(CKA_NETSCAPE_TRUST_EMAIL_PROTECTION),
                new CK_ATTRIBUTE(CKA_NETSCAPE_CERT_SHA1_HASH),
            };

            token.p11.C_GetAttributeValue(session.id(), handle, attrs);
            serverAuth = attrs[0].getLong();
            codeSigning = attrs[1].getLong();
            emailProtection = attrs[2].getLong();
            shaHash = attrs[3].getByteArray();

            attrs = new CK_ATTRIBUTE[] {
                new CK_ATTRIBUTE(CKA_NETSCAPE_TRUST_CLIENT_AUTH),
            };
            long c;
            try {
                token.p11.C_GetAttributeValue(session.id(), handle, attrs);
                c = attrs[0].getLong();
            } catch (PKCS11Exception e) {
                // trust anchor module does not support this attribute
                c = serverAuth;
            }
            clientAuth = c;
        }
        Bytes getHash() {
            return new Bytes(shaHash);
        }
        boolean isTrusted(TrustType type) {
            switch (type) {
            case CLIENT_AUTH:
                return isTrusted(clientAuth);
            case SERVER_AUTH:
                return isTrusted(serverAuth);
            case CODE_SIGNING:
                return isTrusted(codeSigning);
            case EMAIL_PROTECTION:
                return isTrusted(emailProtection);
            case ALL:
                return isTrusted(TrustType.CLIENT_AUTH)
                    && isTrusted(TrustType.SERVER_AUTH)
                    && isTrusted(TrustType.CODE_SIGNING)
                    && isTrusted(TrustType.EMAIL_PROTECTION);
            default:
                return false;
            }
        }

        private boolean isTrusted(long l) {
            // XXX CKT_TRUSTED?
            return (l == CKT_NETSCAPE_TRUSTED_DELEGATOR);
        }

    }

    private static class Bytes {
        final byte[] b;
        Bytes(byte[] b) {
            this.b = b;
        }
        public int hashCode() {
            return Arrays.hashCode(b);
        }
        public boolean equals(Object o) {
            if (this == o) {
                return true;
            }
            if (o instanceof Bytes == false) {
                return false;
            }
            Bytes other = (Bytes)o;
            return Arrays.equals(this.b, other.b);
        }
    }

    private static Map<Bytes,TrustAttributes> getTrust(SunPKCS11 provider)
            throws PKCS11Exception {
        Map<Bytes,TrustAttributes> trustMap = new HashMap();
        Token token = provider.getToken();
        Session session = null;
        try {
            session = token.getOpSession();
            int MAX_NUM = 8192;
            CK_ATTRIBUTE[] attrs = new CK_ATTRIBUTE[] {
                new CK_ATTRIBUTE(CKA_CLASS, CKO_NETSCAPE_TRUST),
            };
            token.p11.C_FindObjectsInit(session.id(), attrs);
            long[] handles = token.p11.C_FindObjects(session.id(), MAX_NUM);
            token.p11.C_FindObjectsFinal(session.id());
            if (DEBUG) System.out.println("handles: " + handles.length);

            for (long handle : handles) {
                try {
                    TrustAttributes trust = new TrustAttributes(token, session, handle);
                    trustMap.put(trust.getHash(), trust);
                } catch (PKCS11Exception e) {
                    // skip put on pkcs11 error
                }
            }
        } finally {
            token.releaseSession(session);
        }
        return trustMap;
    }

    private static native long nssGetLibraryHandle(String libraryName);

    private static native long nssLoadLibrary(String name) throws IOException;

    private static native boolean nssVersionCheck(long handle, String minVersion);

    private static native boolean nssInitialize(String functionName, long handle, String configDir, boolean nssOptimizeSpace);

    private static native Object nssGetModuleList(long handle, String libDir);

}

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