+
−/*
+
− * This Source Code Form is subject to the terms of the Mozilla Public
+
− * License, v. 2.0.  If a copy of the MPL was not distributed with this
+
− * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+
− *
+
− * Copyright 1997 - July 2008 CWI, August 2008 - 2017 MonetDB B.V.
+
− */
+
−
+
−package nl.cwi.monetdb.mcl.connection.helpers;
+
−
+
−import java.security.MessageDigest;
+
−import java.security.NoSuchAlgorithmException;
+
−
+
−/**
+
− * A helper class to process Hash digests during the authentication process.
+
− *
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− * @author Fabian Groffen, Pedro Ferreira
+
− */
+
−public final class ChannelSecurity {
+
−
+
−    private static char HexChar(int n) { return (n > 9) ? (char) ('a' + (n - 10)) : (char) ('0' + n); }
+
−
+
−    /**
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−     * Helper method to convert a byte string to a hexadecimal String representation.
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−     *
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−     * @param digest The byte array to convert
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−     * @return The byte array as a hexadecimal string
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−     */
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−    private static String ToHex(byte[] digest) {
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−        char[] result = new char[digest.length * 2];
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−        int pos = 0;
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−        for (byte aDigest : digest) {
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−            result[pos++] = HexChar((aDigest & 0xf0) >> 4);
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−            result[pos++] = HexChar(aDigest & 0x0f);
+
−        }
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−        return new String(result);
+
−    }
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−
+
−    /**
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−     * Digests several byte[] into a String digest, using a specified hash algorithm.
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−     *
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−     * @param algorithm The hash algorithm to use
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−     * @param toDigests The Strings to digest
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−     * @return The Strings digest as a hexadecimal string
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−     */
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−    public static String DigestStrings(String algorithm, byte[]... toDigests) {
+
−        try {
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−            MessageDigest md = MessageDigest.getInstance(algorithm);
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−            for (byte[] str : toDigests) {
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−                md.update(str);
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−            }
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−            return ToHex(md.digest());
+
−        } catch (NoSuchAlgorithmException e) {
+
−            throw new AssertionError("internal error: " + e.toString());
+
−        }
+
−    }
+
−}