+
−package nl.cwi.monetdb.util;
+
−
+
−import java.io.UnsupportedEncodingException;
+
−import java.security.MessageDigest;
+
−import java.security.NoSuchAlgorithmException;
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−
+
−/**
+
− * Created by ferreira on 12/1/16.
+
− */
+
−public class ChannelSecurity {
+
−
+
−    private static char HexChar(int n) { return (n > 9) ? (char) ('a' + (n - 10)) : (char) ('0' + n); }
+
−
+
−    /**
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−     * Small helper method to convert a byte string to a hexadecimal
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−     * 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 hexadecimal string
+
−     */
+
−    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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−
+
−    public static String DigestStrings(String algorithm, String... toDigests) {
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−        try {
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−            MessageDigest md = MessageDigest.getInstance(algorithm);
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−            for (String str : toDigests) {
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−                md.update(str.getBytes("UTF-8"));
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−            }
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−            byte[] digest = md.digest();
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−            return ToHex(digest);
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−        } catch (NoSuchAlgorithmException | UnsupportedEncodingException e) {
+
−            throw new AssertionError("internal error: " + e.toString());
+
−        }
+
−    }
+
−}