// --- BEGIN COPYRIGHT BLOCK ---
// This program is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; version 2 of the License.
//
// This program 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 for more details.
//
// You should have received a copy of the GNU General Public License along
// with this program; if not, write to the Free Software Foundation, Inc.,
// 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
//
// (C) 2007 Red Hat, Inc.
// All rights reserved.
// --- END COPYRIGHT BLOCK ---
package com.netscape.cmscore.security;

import java.io.BufferedReader;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.PrintStream;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.StringTokenizer;

import org.mozilla.jss.CryptoManager;
import org.mozilla.jss.CryptoManager.NotInitializedException;
import org.mozilla.jss.SecretDecoderRing.Decryptor;
import org.mozilla.jss.SecretDecoderRing.Encryptor;
import org.mozilla.jss.SecretDecoderRing.KeyManager;
import org.mozilla.jss.crypto.CryptoToken;
import org.mozilla.jss.crypto.TokenException;
import org.mozilla.jss.util.Base64OutputStream;
import org.mozilla.jss.util.Password;

import com.netscape.certsrv.apps.CMS;
import com.netscape.certsrv.base.EBaseException;
import com.netscape.certsrv.logging.ILogger;
import com.netscape.cmsutil.util.Utils;

/* 
 * A class for managing passwords in the SDR password cache
 *
 * @author Christina Fu
 * @version $Revision$, $Date$
 */
public class PWsdrCache {
    public static final String PROP_PWC_TOKEN_NAME = "pwcTokenname";
    public static final String PROP_PWC_KEY_ID = "pwcKeyid";
    public static final String PROP_PWC_NICKNAME = "sso_key";

    private ILogger mLogger = null;
    private String mPWcachedb = null;
    // mTool tells if this is called from the PasswordCache tool
    private boolean mIsTool = false;
    private byte[] mKeyID = null;
    private String mTokenName = null;
    private CryptoToken mToken = null;

    // for CMSEngine
    public PWsdrCache() throws EBaseException {
        mLogger = CMS.getLogger();
        try {
            mPWcachedb = CMS.getConfigStore().getString("pwCache");
            CMS.debug("got pwCache file path from configstore");
        } catch (Exception e) {
            log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_GET_CONFIG"));
            // let it fall through
        }
        initToken();
        initKey();
    }

    private void initToken() throws EBaseException {
        if (mToken == null) {
            CryptoManager cm = null;
            try {
                cm = CryptoManager.getInstance();
                mTokenName = CMS.getConfigStore().getString(PROP_PWC_TOKEN_NAME);
                log(ILogger.LL_DEBUG, "pwcTokenname specified.  Use token for SDR key. tokenname= " + mTokenName);
                mToken = cm.getTokenByName(mTokenName);
            } catch (NotInitializedException e) {
                log(ILogger.LL_FAILURE, e.toString());
                throw new EBaseException(e.toString());
            } catch (Exception e) {
                log(ILogger.LL_DEBUG, "no pwcTokenname specified, use internal token for SDR key");
                mToken = cm.getInternalKeyStorageToken();
            }
        }
    }

    // called from PWCBsdr or CMSEngine only
    private void initKey() throws EBaseException {
        if (mKeyID == null) {
            try {
                String keyID = CMS.getConfigStore().getString(PROP_PWC_KEY_ID);
                log(ILogger.LL_DEBUG, "retrieved PWC SDR key");
                mKeyID = base64Decode(keyID);

            } catch (Exception e) {
                log(ILogger.LL_DEBUG, "no pwcSDRKey specified");
                throw new EBaseException(e.toString());
            }
        }
    }

    // for PasswordCache tool (isTool == true)
    // and installation wizard (isTool == false)
    // Do not use for PWCBsdr, since we don't want to mistakenly
    // generate SDR keys in case of configuration errors
    public PWsdrCache(String pwCache, String pwcTokenname, byte[] keyId,
                      boolean isTool) throws Exception {
        mPWcachedb = pwCache;
        mIsTool = isTool;
        mTokenName = pwcTokenname;
        CryptoManager cm = null;

        if (keyId != null) {
            mKeyID = keyId;
        }

        cm = CryptoManager.getInstance();
        if (mTokenName != null) {
            mToken = cm.getTokenByName(mTokenName);
            mToken = cm.getInternalKeyStorageToken();
            debug("PWsdrCache: mToken = " + mTokenName);
        } else {
            mToken = cm.getInternalKeyStorageToken();
            debug("PWsdrCache: mToken = internal");
        }
    }

    public byte[] getKeyId() {
        return mKeyID;
    }

    public String getTokenName() {
        return mTokenName;
    }

    public void deleteUniqueNamedKey(String nickName)
            throws Exception {
        KeyManager km = new KeyManager(mToken);
        km.deleteUniqueNamedKey(nickName);
    }

    public byte[] generateSDRKey() throws Exception {
        return generateSDRKeyWithNickName(PROP_PWC_NICKNAME);
    }

    public byte[] generateSDRKeyWithNickName(String nickName)
            throws Exception {
        try {

            if (mIsTool != true) {
                // generate SDR key
                KeyManager km = new KeyManager(mToken);
                try {
                    // Bugscape Bug #54838:  Due to the CMS cloning feature,
                    //                       we must check for the presence of
                    //                       a uniquely named symmetric key
                    //                       prior to making an attempt to
                    //                       generate it!
                    //
                    if (!(km.uniqueNamedKeyExists(nickName))) {
                        mKeyID = km.generateUniqueNamedKey(nickName);
                    }
                } catch (TokenException e) {
                    log(0, "generateSDRKey() failed on " + e.toString());
                    throw e;
                }
            }
        } catch (Exception e) {
            log(ILogger.LL_FAILURE, e.toString());
            throw e;
        }
        return mKeyID;
    }

    public byte[] base64Decode(String s) throws IOException {
        byte[] d = com.netscape.osutil.OSUtil.AtoB(s);
        return d;
    }

    public static String base64Encode(byte[] bytes) throws IOException {
        // All this streaming is lame, but Base64OutputStream needs a
        // PrintStream
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        Base64OutputStream b64 = new Base64OutputStream(new
                PrintStream(new
                        FilterOutputStream(output)
                )
                );

        b64.write(bytes);
        b64.flush();

        // This is internationally safe because Base64 chars are
        // contained within 8859_1
        return output.toString("8859_1");
    }

    // for PWCBsdr
    public PWsdrCache(String pwCache, ILogger logger) throws
            EBaseException {
        mLogger = logger;
        mPWcachedb = pwCache;
        initToken();
        initKey();
    }

    public void addEntry(String tag, String pwd) throws EBaseException {
        addEntry(tag, pwd, (Hashtable<String, String>) null);
    }

    /*
     * Store passwd in pwcache.
     */
    public void addEntry(Hashtable<String, String> ht) throws EBaseException {
        addEntry((String) null, (String) null, ht);
    }

    /*
     * add passwd in pwcache.
     */
    public void addEntry(String tag, String pwd, Hashtable<String, String> tagPwds) throws EBaseException {

        String stringToAdd = null;
        String bufs = null;

        if (tagPwds == null) {
            stringToAdd = tag + ":" + pwd + "\n";
        } else {
            Enumeration<String> enum1 = tagPwds.keys();

            while (enum1.hasMoreElements()) {
                tag = enum1.nextElement();
                pwd = tagPwds.get(tag);
                debug("password tag: " + tag + " stored in " + mPWcachedb);

                if (stringToAdd == null) {
                    stringToAdd = tag + ":" + pwd + "\n";
                } else {
                    stringToAdd += tag + ":" + pwd + "\n";
                }
            }
        }

        String dcrypts = readPWcache();

        if (dcrypts != null) {
            // converts to Hashtable, replace if tag exists, add
            //                if tag doesn't exist
            Hashtable ht = string2Hashtable(dcrypts);

            if (ht.containsKey(tag) == false) {
                debug("adding new tag: " + tag);
                ht.put(tag, pwd);
            } else {
                debug("replacing tag: " + tag);
                ht.put(tag, pwd);
            }
            bufs = hashtable2String(ht);
        } else {
            debug("adding new tag: " + tag);
            bufs = stringToAdd;
        }

        // write update to cache
        writePWcache(bufs);
    }

    /*
     * delete passwd in pwcache.
     */
    public void deleteEntry(String tag) throws EBaseException {
        String bufs = null;

        String dcrypts = readPWcache();

        if (dcrypts != null) {
            // converts to Hashtable, replace if tag exists, add
            //                if tag doesn't exist
            Hashtable ht = string2Hashtable(dcrypts);

            if (ht.containsKey(tag) == false) {
                debug("tag: " + tag + " does not exist");
                return;
            } else {
                debug("deleting tag: " + tag);
                ht.remove(tag);
            }
            bufs = hashtable2String(ht);
        } else {
            debug("password cache contains no tags");
            return;
        }

        // write update to cache
        writePWcache(bufs);
    }

    /*
     * reads and decrypts the pwcache.db content
     */
    public String readPWcache() throws EBaseException {
        debug("about to read password cache");
        String dcrypts = null;
        Decryptor sdr = new Decryptor(mToken);

        // not used, but could used for debugging
        int totalRead = 0;
        FileInputStream inputs = null;
        ByteArrayOutputStream bos = new ByteArrayOutputStream();

        try {
            // for SDR -> read, decrypt, append, and write
            inputs = new FileInputStream(mPWcachedb);
            byte[] readbuf = new byte[2048]; // for now
            int numRead = 0;

            while ((numRead = inputs.read(readbuf)) != -1) {
                bos.write(readbuf, 0, numRead);
                totalRead += numRead;
            }
            inputs.close();
        } catch (FileNotFoundException e) {
            log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_FILE", mPWcachedb, e.toString()));
            throw new EBaseException(e.toString() + ": " + mPWcachedb);
        } catch (IOException e) {
            log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_FILE", mPWcachedb, e.toString()));
            throw new EBaseException(e.toString() + ": " + mPWcachedb);
        }

        if (totalRead > 0) {
            try {
                // decrypt it first to append
                byte[] dcryptb = sdr.decrypt(bos.toByteArray());

                dcrypts = new String(dcryptb, "UTF-8");
            } catch (Exception e) {
                log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_DECRYPT", e.toString()));
                e.printStackTrace();
                throw new EBaseException("password cache decrypt failed");
            }
        }

        return dcrypts;
    }

    /*
     * encrypts and writes the whole String buf into pwcache.db
     */
    public void writePWcache(String bufs) throws EBaseException {
        try {
            Encryptor sdr = new Encryptor(mToken, mKeyID,
                                Encryptor.DEFAULT_ENCRYPTION_ALG);

            byte[] writebuf = null;

            try {
                // now encrypt it again
                writebuf = sdr.encrypt(bufs.getBytes("UTF-8"));
            } catch (Exception e) {
                log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_ENCRYPT", e.toString()));
                e.printStackTrace();
                throw new EBaseException("password cache encrypt failed");
            }

            File tmpPWcache = new File(mPWcachedb + ".tmp");

            if (tmpPWcache.exists()) {
                // it wasn't removed?
                tmpPWcache.delete();
                tmpPWcache = new File(mPWcachedb + ".tmp");
            }
            FileOutputStream outstream = new FileOutputStream(mPWcachedb + ".tmp");

            outstream.write(writebuf);
            outstream.close();

            File origFile = new File(mPWcachedb);

            try {
                if (Utils.isNT()) {
                    // NT is very picky on the path
                    Utils.exec("copy " +
                                tmpPWcache.getAbsolutePath().replace('/',
                                                                      '\\') +
                                " " +
                                origFile.getAbsolutePath().replace('/',
                                                                    '\\'));
                } else {
                    // Create a copy of the original file which
                    // preserves the original file permissions.
                    Utils.exec("cp -p " + tmpPWcache.getAbsolutePath() + " " +
                                origFile.getAbsolutePath());
                }

                // Remove the original file if and only if
                // the backup copy was successful.
                if (origFile.exists()) {
                    if (!Utils.isNT()) {
                        try {
                            Utils.exec("chmod 00660 " +
                                        origFile.getCanonicalPath());
                        } catch (IOException e) {
                            CMS.debug("Unable to change file permissions on "
                                     + origFile.toString());
                        }
                    }
                    tmpPWcache.delete();
                    debug("operation completed for " + mPWcachedb);
                }
            } catch (Exception exx) {
                log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_CACHE", exx.toString()));
                throw new EBaseException(exx.toString() + ": " + mPWcachedb);
            }
        } catch (FileNotFoundException e) {
            log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_FILE", mPWcachedb, e.toString()));
            throw new EBaseException(e.toString() + ": " + mPWcachedb);
        } catch (IOException e) {
            log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_FILE", mPWcachedb, e.toString()));
            throw new EBaseException(e.toString() + ": " + mPWcachedb);
        } catch (Exception e) {
            log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_FILE", mPWcachedb, e.toString()));
            throw new EBaseException(e.toString() + ": " + mPWcachedb);
        }
    }

    public String hashtable2String(Hashtable<String, String> ht) {
        Enumeration<String> enum1 = ht.keys();
        String returnString = null;

        while (enum1.hasMoreElements()) {
            String tag = enum1.nextElement();
            String pwd = ht.get(tag);

            if (returnString == null) {
                returnString = tag + ":" + pwd + "\n";
            } else {
                returnString += tag + ":" + pwd + "\n";
            }
        }
        return returnString;
    }

    public Hashtable<String, String> string2Hashtable(String cache) {
        Hashtable<String, String> ht = new Hashtable<String, String>();

        // first, break into lines
        StringTokenizer st = new StringTokenizer(cache, "\n");

        while (st.hasMoreTokens()) {
            String line = (String) st.nextToken();
            // break into tag:password format for each line
            int colonIdx = line.indexOf(":");

            if (colonIdx != -1) {
                String tag = line.substring(0, colonIdx);
                String passwd = line.substring(colonIdx + 1,
                        line.length());

                ht.put(tag.trim(), passwd.trim());
            } else {
                //invalid format...log or throw...later
            }
        }
        return ht;
    }

    /*
     * get password from cache.  This one supplies cache file name
     */
    public Password getEntry(String fileName, String tag) {
        mPWcachedb = fileName;
        return getEntry(tag);
    }

    /*
     * if tag found with pwd, return it
     * if tag not found, return null, which will cause it to give up
     */
    public Password getEntry(String tag) {
        Hashtable pwTable = null;
        String pw = null;

        debug("in getEntry, tag=" + tag);

        if (mPWcachedb == null) {
            debug("mPWcachedb file path name is not initialized");
            return null;
        }

        String dcrypts = null;

        try {
            dcrypts = readPWcache();
        } catch (EBaseException e) {
            log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_READ", e.toString()));
            return null;
        }

        if (dcrypts != null) {
            // parse the cache
            String cache = dcrypts;

            // this is created and destroyed at each use
            pwTable = string2Hashtable(cache);
            debug("in getEntry, pw cache parsed");
            pw = (String) pwTable.get(tag);
        }

        if (pw != null) {
            debug("getEntry gotten password for " + tag);
            return new Password(pw.toCharArray());
        } else {
            log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_TAG", tag));
            return null;
        }
    }

    //copied from IOUtil.java
    /**
     * Checks if this is NT.
     */
    public static boolean isNT() {
        return ((File.separator).equals("\\"));
    }

    public static boolean exec(String cmd) throws EBaseException {
        try {
            String cmds[] = null;

            if (isNT()) {
                // NT
                cmds = new String[3];
                cmds[0] = "cmd";
                cmds[1] = "/c";
                cmds[2] = cmd;
            } else {
                // UNIX
                cmds = new String[3];
                cmds[0] = "/bin/sh";
                cmds[1] = "-c";
                cmds[2] = cmd;
            }
            Process process = Runtime.getRuntime().exec(cmds);

            process.waitFor();
            BufferedReader pOut = null;
            String l = null;

            if (process.exitValue() == 0) {

                /**
                 * pOut = new BufferedReader(
                 * new InputStreamReader(process.getInputStream()));
                 * while ((l = pOut.readLine()) != null) {
                 * System.out.println(l);
                 * }
                 **/
                return true;
            } else {

                /**
                 * pOut = new BufferedReader(
                 * new InputStreamReader(process.getErrorStream()));
                 * l = null;
                 * while ((l = pOut.readLine()) != null) {
                 * System.out.println(l);
                 * }
                 **/
                return false;
            }
        } catch (Exception e) {
            return false;
        }
    }

    public void debug(String msg) {
        if (mLogger != null) {
            CMS.debug(msg);
        }
    }

    public void log(int level, String msg) {
        if (mLogger != null) {
            mLogger.log(ILogger.EV_SYSTEM, ILogger.S_OTHER, level,
                    "PWsdrCache " + msg);
        } else if (mIsTool) {
            System.out.println(msg);
        } // else it's most likely the installation wizard...no logging
    }

    /*
     * list passwds in pwcache.
     */
    public boolean pprint() {
        String bufs = null;
        String dcrypts = null;

        try {
            dcrypts = readPWcache();
        } catch (EBaseException e) {
            log(ILogger.LL_FAILURE, CMS.getLogMessage("CMSCORE_SECURITY_PW_READ", e.toString()));
            return false;
        }

        debug("----- Password Cache Content -----");

        if (dcrypts != null) {
            // first, break into lines
            StringTokenizer st = new StringTokenizer(dcrypts, "\n");

            while (st.hasMoreTokens()) {
                String line = (String) st.nextToken();
                // break into tag:password format for each line
                int colonIdx = line.indexOf(":");

                if (colonIdx != -1) {
                    String tag = line.substring(0, colonIdx);
                    String passwd = line.substring(colonIdx + 1,
                            line.length());

                    debug(tag.trim() +
                            " : " + passwd.trim());
                } else {
                    //invalid format...log or throw...later
                    debug("invalid format");
                }
            }
        } // else print nothing
        return true;
    }
}