1 | var crypto = require("crypto");
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2 | var BigInteger = require("jsbn").BigInteger;
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3 | var ECPointFp = require("./lib/ec.js").ECPointFp;
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4 | var Buffer = require("safer-buffer").Buffer;
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5 | exports.ECCurves = require("./lib/sec.js");
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6 |
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7 |
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8 | function unstupid(hex,len)
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9 | {
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10 | return (hex.length >= len) ? hex : unstupid("0"+hex,len);
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11 | }
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12 |
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13 | exports.ECKey = function(curve, key, isPublic)
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14 | {
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15 | var priv;
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16 | var c = curve();
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17 | var n = c.getN();
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18 | var bytes = Math.floor(n.bitLength()/8);
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19 |
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20 | if(key)
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21 | {
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22 | if(isPublic)
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23 | {
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24 | var curve = c.getCurve();
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25 |
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26 |
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27 |
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28 |
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29 |
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30 | this.P = curve.decodePointHex(key.toString("hex"));
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31 | }else{
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32 | if(key.length != bytes) return false;
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33 | priv = new BigInteger(key.toString("hex"), 16);
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34 | }
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35 | }else{
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36 | var n1 = n.subtract(BigInteger.ONE);
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37 | var r = new BigInteger(crypto.randomBytes(n.bitLength()));
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38 | priv = r.mod(n1).add(BigInteger.ONE);
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39 | this.P = c.getG().multiply(priv);
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40 | }
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41 | if(this.P)
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42 | {
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43 |
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44 |
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45 | this.PublicKey = Buffer.from(c.getCurve().encodeCompressedPointHex(this.P),"hex");
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46 | }
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47 | if(priv)
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48 | {
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49 | this.PrivateKey = Buffer.from(unstupid(priv.toString(16),bytes*2),"hex");
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50 | this.deriveSharedSecret = function(key)
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51 | {
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52 | if(!key || !key.P) return false;
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53 | var S = key.P.multiply(priv);
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54 | return Buffer.from(unstupid(S.getX().toBigInteger().toString(16),bytes*2),"hex");
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55 | }
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56 | }
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57 | }
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58 |
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