Add missing classes for event composer

This commit is contained in:
@s.roertgen 2025-01-16 22:43:25 +01:00
parent ca68ff05bf
commit bea0d5822e
7 changed files with 538 additions and 1 deletions

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@ -4,6 +4,8 @@ Do nostr stuff with Clojure.
Heavy WIP. At this point it probably won't make much sense too you.
You might have to run `javac -d java $(find java -name "*.java")`
## Usage
FIXME: write usage documentation!

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@ -1,4 +1,4 @@
{:paths ["src" "resources"]
{:paths ["src" "resources" "java"]
:deps {org.clojure/clojure {:mvn/version "1.12.0"}
cheshire/cheshire {:mvn/version "5.13.0"}
hato/hato {:mvn/version "1.0.0"}}

128
java/schnorr/Main.java Normal file
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@ -0,0 +1,128 @@
package schnorr;
import java.util.Arrays;
public class Main {
public static void main(String[] args) {
String[] data = {
// index,secret key,public key, aux rand, message,signature,verification result,comment
"0,0000000000000000000000000000000000000000000000000000000000000003,F9308A019258C31049344F85F89D5229B531C845836F99B08601F113BCE036F9,0000000000000000000000000000000000000000000000000000000000000000,0000000000000000000000000000000000000000000000000000000000000000,E907831F80848D1069A5371B402410364BDF1C5F8307B0084C55F1CE2DCA821525F66A4A85EA8B71E482A74F382D2CE5EBEEE8FDB2172F477DF4900D310536C0,TRUE",
"1,B7E151628AED2A6ABF7158809CF4F3C762E7160F38B4DA56A784D9045190CFEF,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,0000000000000000000000000000000000000000000000000000000000000001,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,6896BD60EEAE296DB48A229FF71DFE071BDE413E6D43F917DC8DCF8C78DE33418906D11AC976ABCCB20B091292BFF4EA897EFCB639EA871CFA95F6DE339E4B0A,TRUE",
"2,C90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B14E5C9,DD308AFEC5777E13121FA72B9CC1B7CC0139715309B086C960E18FD969774EB8,C87AA53824B4D7AE2EB035A2B5BBBCCC080E76CDC6D1692C4B0B62D798E6D906,7E2D58D8B3BCDF1ABADEC7829054F90DDA9805AAB56C77333024B9D0A508B75C,5831AAEED7B44BB74E5EAB94BA9D4294C49BCF2A60728D8B4C200F50DD313C1BAB745879A5AD954A72C45A91C3A51D3C7ADEA98D82F8481E0E1E03674A6F3FB7,TRUE",
"3,0B432B2677937381AEF05BB02A66ECD012773062CF3FA2549E44F58ED2401710,25D1DFF95105F5253C4022F628A996AD3A0D95FBF21D468A1B33F8C160D8F517,FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF,FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF,7EB0509757E246F19449885651611CB965ECC1A187DD51B64FDA1EDC9637D5EC97582B9CB13DB3933705B32BA982AF5AF25FD78881EBB32771FC5922EFC66EA3,TRUE,test fails if msg is reduced modulo p or n",
"4,,D69C3509BB99E412E68B0FE8544E72837DFA30746D8BE2AA65975F29D22DC7B9,,4DF3C3F68FCC83B27E9D42C90431A72499F17875C81A599B566C9889B9696703,00000000000000000000003B78CE563F89A0ED9414F5AA28AD0D96D6795F9C6376AFB1548AF603B3EB45C9F8207DEE1060CB71C04E80F593060B07D28308D7F4,TRUE",
"5,,EEFDEA4CDB677750A420FEE807EACF21EB9898AE79B9768766E4FAA04A2D4A34,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E17776969E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B,FALSE,public key not on the curve",
"6,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,FFF97BD5755EEEA420453A14355235D382F6472F8568A18B2F057A14602975563CC27944640AC607CD107AE10923D9EF7A73C643E166BE5EBEAFA34B1AC553E2,FALSE,has_even_y(R) is false",
"7,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,1FA62E331EDBC21C394792D2AB1100A7B432B013DF3F6FF4F99FCB33E0E1515F28890B3EDB6E7189B630448B515CE4F8622A954CFE545735AAEA5134FCCDB2BD,FALSE,negated message",
"8,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E177769961764B3AA9B2FFCB6EF947B6887A226E8D7C93E00C5ED0C1834FF0D0C2E6DA6,FALSE,negated s value",
"9,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,0000000000000000000000000000000000000000000000000000000000000000123DDA8328AF9C23A94C1FEECFD123BA4FB73476F0D594DCB65C6425BD186051,FALSE,sG - eP is infinite. Test fails in single verification if has_even_y(inf) is defined as true and x(inf) as 0",
"10,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,00000000000000000000000000000000000000000000000000000000000000017615FBAF5AE28864013C099742DEADB4DBA87F11AC6754F93780D5A1837CF197,FALSE,sG - eP is infinite. Test fails in single verification if has_even_y(inf) is defined as true and x(inf) as 1",
"11,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,4A298DACAE57395A15D0795DDBFD1DCB564DA82B0F269BC70A74F8220429BA1D69E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B,FALSE,sig[0:32] is not an X coordinate on the curve",
"12,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F69E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B,FALSE,sig[0:32] is equal to field size",
"13,,DFF1D77F2A671C5F36183726DB2341BE58FEAE1DA2DECED843240F7B502BA659,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E177769FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141,FALSE,sig[32:64] is equal to curve order",
"14,,FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC30,,243F6A8885A308D313198A2E03707344A4093822299F31D0082EFA98EC4E6C89,6CFF5C3BA86C69EA4B7376F31A9BCB4F74C1976089B2D9963DA2E5543E17776969E89B4C5564D00349106B8497785DD7D1D713A8AE82B32FA79D5F7FC407D39B,FALSE,public key is not a valid X coordinate because it exceeds the field size",
};
boolean allSigsPassed = true;
boolean allVerifsPassed = true;
for(int i = 0; i < data.length; i++) {
String[] s = data[i].split(",");
String index = s[0];
String seckey = s[1];
String pubkey = s[2];
String auxrand = s[3];
String msg = s[4];
String sig = s[5];
String result = s[6];
String comment = (s.length == 8) ? s[7] : null;
byte[] _pubkey = Util.hexToBytes(pubkey);
byte[] _auxrand = Util.hexToBytes(auxrand);
byte[] _msg = Util.hexToBytes(msg);
byte[] _sig = Util.hexToBytes(sig);
boolean _result = result.equals("TRUE");
System.out.println("\nTest vector:" + Integer.valueOf(index));
if(seckey != null && seckey.length() > 0) {
byte[] _seckey = Util.hexToBytes(seckey);
try {
byte[] _pubkeyActual = Point.genPubKey(_seckey);
if(!Arrays.equals(_pubkey, _pubkeyActual)) {
System.out.println(" * Failed key generation.");
System.out.println("\tExpected key:" + Util.bytesToHex(_pubkey));
System.out.println("\tActual key:" + Util.bytesToHex(_pubkeyActual));
allSigsPassed = false;
}
}
catch(Exception e) {
System.out.println(e.getMessage());
}
try {
byte[] _sigActual = Schnorr.sign(_msg, _seckey, _auxrand);
if(Arrays.equals(_sig, _sigActual)) {
System.out.println(" * Passed signing test.");
}
else {
System.out.println(" * Failed signing test.");
System.out.println("\tExpected signature:" + Util.bytesToHex(_sig));
System.out.println("\tActual signature:" + Util.bytesToHex(_sigActual));
allSigsPassed = false;
}
}
catch(Exception e) {
System.out.println(e.getMessage());
allSigsPassed = false;
}
}
try {
boolean resultActual = Schnorr.verify(_msg, _pubkey, _sig);
if(_result == resultActual) {
System.out.println(" * Passed verification test.");
}
else {
System.out.println(" * Failed verification test.");
System.out.println("\tExpected verification result:" + result);
System.out.println("\tActual verification result:" + resultActual);
if(comment != null) {
System.out.println("\tComment:" + comment);
}
allVerifsPassed = false;
}
}
catch(Exception e) {
if(_result) {
System.out.println("Exception:" + e.getMessage());
System.out.println(" * Failed verification test.");
allVerifsPassed = false;
}
else {
System.out.println(" * Passed verification test.");
}
}
}
if(allSigsPassed && allVerifsPassed) {
System.out.println("All test vectors passed.");
}
else {
System.out.println("Some test vectors failed.");
}
}
}

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java/schnorr/Pair.java Normal file
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package schnorr;
// clone of org.apache.commons.lang3.tuple.Pair;
public class Pair<K, V> {
private K elementLeft = null;
private V elementRight = null;
protected Pair() {
}
public static <K, V> Pair<K, V> of(K elementLeft, V elementRight) {
return new Pair<>(elementLeft, elementRight);
}
public Pair(K elementLeft, V elementRight) {
this.elementLeft = elementLeft;
this.elementRight = elementRight;
}
public K getLeft() {
return elementLeft;
}
public V getRight() {
return elementRight;
}
public boolean equals(Pair<K, V> p) {
return (this.elementLeft.equals(p.getLeft())) && (this.elementRight.equals(p.getRight()));
}
}

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java/schnorr/Point.java Normal file
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package schnorr;
import java.math.BigInteger;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
public class Point {
final static private BigInteger p = new BigInteger("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEFFFFFC2F", 16);
final static private BigInteger n = new BigInteger("FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141", 16);
final static public Point G = new Point(
new BigInteger("79BE667EF9DCBBAC55A06295CE870B07029BFCDB2DCE28D959F2815B16F81798", 16),
new BigInteger("483ADA7726A3C4655DA4FBFC0E1108A8FD17B448A68554199C47D08FFB10D4B8", 16)
);
private static final BigInteger BI_TWO = BigInteger.valueOf(2);
private final Pair<BigInteger,BigInteger> pair;
public Point(BigInteger x , BigInteger y) {
pair = Pair.of(x, y);
}
public Point(byte[] b0, byte[] b1) {
pair = Pair.of(new BigInteger(1, b0), new BigInteger(1, b1));
}
public static BigInteger getp() {
return p;
}
public static BigInteger getn() {
return n;
}
public static Point getG() {
return G;
}
public BigInteger getX() {
return pair.getLeft();
}
public BigInteger getY() {
return pair.getRight();
}
public static BigInteger getX(Point P) {
assert !P.isInfinite();
return P.getX();
}
public static BigInteger getY(Point P) {
assert !P.isInfinite();
return P.getY();
}
public Pair<BigInteger,BigInteger> getPair() {
return pair;
}
public boolean isInfinite() {
return pair == null || pair.getLeft() == null || pair.getRight() == null;
}
public static boolean isInfinite(Point P) {
return P.isInfinite();
}
public Point add(Point P) {
return add(this, P);
}
public static Point add(Point P1, Point P2) {
if((P1 != null && P2 != null && P1.isInfinite() && P2.isInfinite())) {
return infinityPoint();
}
if(P1 == null || P1.isInfinite()) {
return P2;
}
if(P2 == null || P2.isInfinite()) {
return P1;
}
if(P1.getX().equals(P2.getX()) && !P1.getY().equals(P2.getY())) {
return infinityPoint();
}
BigInteger lam;
if(P1.equals(P2)) {
BigInteger base = P2.getY().multiply(BI_TWO);
lam = (BigInteger.valueOf(3L).multiply(P1.getX()).multiply(P1.getX()).multiply(base.modPow(p.subtract(BI_TWO), p))).mod(p);
}
else {
BigInteger base = P2.getX().subtract(P1.getX());
lam = ((P2.getY().subtract(P1.getY())).multiply(base.modPow(p.subtract(BI_TWO), p))).mod(p);
}
BigInteger x3 = (lam.multiply(lam).subtract(P1.getX()).subtract(P2.getX())).mod(p);
return new Point(x3, lam.multiply(P1.getX().subtract(x3)).subtract(P1.getY()).mod(p));
}
public Point mul(BigInteger n) {
return mul(this, n);
}
public static Point mul(Point P, BigInteger n) {
Point R = null;
for(int i = 0; i < 256; i++) {
if (n.shiftRight(i).and(BigInteger.ONE).compareTo(BigInteger.ZERO) > 0) {
R = add(R, P);
}
P = add(P, P);
}
return R;
}
public boolean hasEvenY() {
return hasEvenY(this);
}
public static boolean hasEvenY(Point P) {
return P.getY().mod(BI_TWO).compareTo(BigInteger.ZERO) == 0;
}
public static boolean isSquare(BigInteger x) {
return x.modPow(p.subtract(BigInteger.ONE).mod(BI_TWO), p).longValue() == 1L;
}
public boolean hasSquareY() {
return hasSquareY(this);
}
public static boolean hasSquareY(Point P) {
assert !isInfinite(P);
return isSquare(P.getY());
}
public static byte[] taggedHash(String tag, byte[] msg) throws NoSuchAlgorithmException {
MessageDigest digest = MessageDigest.getInstance("SHA-256");
byte[] tagHash = Util.sha256(tag.getBytes());
int len = (tagHash.length * 2) + msg.length;
byte[] buf = new byte[len];
System.arraycopy(tagHash, 0, buf, 0, tagHash.length);
System.arraycopy(tagHash, 0, buf, tagHash.length, tagHash.length);
System.arraycopy(msg, 0, buf, tagHash.length * 2, msg.length);
return Util.sha256(buf);
}
public static byte[] genPubKey(byte[] secKey) throws Exception {
BigInteger x = Util.bigIntFromBytes(secKey);
if(!(BigInteger.ONE.compareTo(x) <= 0 && x.compareTo(getn().subtract(BigInteger.ONE)) <= 0)) {
throw new Exception("The secret key must be an integer in the range 1..n-1.");
}
Point ret = Point.mul(G, x);
return bytesFromPoint(ret);
}
public byte[] toBytes() {
return bytesFromPoint(this);
}
public static byte[] bytesFromPoint(Point P) {
return Util.bytesFromBigInteger(P.getX());
}
// previously 'pointFromBytes()'
public static Point liftX(byte[] b) {
BigInteger x = Util.bigIntFromBytes(b);
if(x.compareTo(p) >= 0) {
return null;
}
BigInteger y_sq = x.modPow(BigInteger.valueOf(3L), p).add(BigInteger.valueOf(7L)).mod(p);
BigInteger y = y_sq.modPow(p.add(BigInteger.ONE).divide(BigInteger.valueOf(4L)), p);
if(y.modPow(BI_TWO, p).compareTo(y_sq) != 0) {
return null;
}
else {
return new Point(x, y.and(BigInteger.ONE).compareTo(BigInteger.ZERO) == 0 ? y : p.subtract(y));
}
}
public static Point infinityPoint() {
return new Point(null, (BigInteger) null);
}
public boolean equals(Point P) {
return getPair().equals(P.getPair());
}
}

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package schnorr;
import java.math.BigInteger;
import java.util.Arrays;
public class Schnorr {
public static byte[] sign(byte[] msg, byte[] secKey, byte[] auxRand) throws Exception {
if(msg.length != 32) {
throw new Exception("The message must be a 32-byte array.");
}
BigInteger secKey0 = Util.bigIntFromBytes(secKey);
if(!(BigInteger.ONE.compareTo(secKey0) <= 0 && secKey0.compareTo(Point.getn().subtract(BigInteger.ONE)) <= 0)) {
throw new Exception("The secret key must be an integer in the range 1..n-1.");
}
Point P = Point.mul(Point.getG(), secKey0);
if(!P.hasEvenY()) {
secKey0 = Point.getn().subtract(secKey0);
}
int len = Util.bytesFromBigInteger(secKey0).length + P.toBytes().length + msg.length;
byte[] buf = new byte[len];
byte[] t = Util.xor(Util.bytesFromBigInteger(secKey0), Point.taggedHash("BIP0340/aux", auxRand));
System.arraycopy(t, 0, buf, 0, t.length);
System.arraycopy(P.toBytes(), 0, buf, t.length, P.toBytes().length);
System.arraycopy(msg, 0, buf, t.length + P.toBytes().length, msg.length);
BigInteger k0 = Util.bigIntFromBytes(Point.taggedHash("BIP0340/nonce", buf)).mod(Point.getn());
if(k0.compareTo(BigInteger.ZERO) == 0) {
throw new Exception("Failure. This happens only with negligible probability.");
}
Point R = Point.mul(Point.getG(), k0);
BigInteger k;
if(!R.hasEvenY()) {
k = Point.getn().subtract(k0);
}
else {
k = k0;
}
len = R.toBytes().length + P.toBytes().length + msg.length;
buf = new byte[len];
System.arraycopy(R.toBytes(), 0, buf, 0, R.toBytes().length);
System.arraycopy(P.toBytes(), 0, buf, R.toBytes().length, P.toBytes().length);
System.arraycopy(msg, 0, buf, R.toBytes().length + P.toBytes().length, msg.length);
BigInteger e = Util.bigIntFromBytes(Point.taggedHash("BIP0340/challenge", buf)).mod(Point.getn());
BigInteger kes = k.add(e.multiply(secKey0)).mod(Point.getn());
len = R.toBytes().length + Util.bytesFromBigInteger(kes).length;
byte[] sig = new byte[len];
System.arraycopy(R.toBytes(), 0, sig, 0, R.toBytes().length);
System.arraycopy(Util.bytesFromBigInteger(kes), 0, sig, R.toBytes().length, Util.bytesFromBigInteger(kes).length);
if(!verify(msg, P.toBytes(), sig)) {
throw new Exception("The signature does not pass verification.");
}
return sig;
}
public static boolean verify(byte[] msg, byte[] pubkey, byte[] sig) throws Exception {
if(msg.length != 32) {
throw new Exception("The message must be a 32-byte array.");
}
if(pubkey.length != 32) {
throw new Exception("The public key must be a 32-byte array.");
}
if(sig.length != 64) {
throw new Exception("The signature must be a 64-byte array.");
}
Point P = Point.liftX(pubkey);
if(P == null) {
return false;
}
BigInteger r = Util.bigIntFromBytes(Arrays.copyOfRange(sig,0, 32));
BigInteger s = Util.bigIntFromBytes(Arrays.copyOfRange(sig,32, 64));
if(r.compareTo(Point.getp()) >= 0 || s.compareTo(Point.getn()) >= 0) {
return false;
}
int len = 32 + pubkey.length + msg.length;
byte[] buf = new byte[len];
System.arraycopy(sig, 0, buf, 0, 32);
System.arraycopy(pubkey, 0, buf, 32, pubkey.length);
System.arraycopy(msg, 0, buf, 32 + pubkey.length, msg.length);
BigInteger e = Util.bigIntFromBytes(Point.taggedHash("BIP0340/challenge", buf)).mod(Point.getn());
Point R = Point.add(Point.mul(Point.getG(), s), Point.mul(P, Point.getn().subtract(e)));
return R != null && R.hasEvenY() && R.getX().compareTo(r) == 0;
}
public static byte[] genPubKey(byte[] secKey) throws Exception {
BigInteger x = Util.bigIntFromBytes(secKey);
if(!(BigInteger.ONE.compareTo(x) <= 0 && x.compareTo(Point.getn().subtract(BigInteger.ONE)) <= 0)) {
throw new Exception("The secret key must be an integer in the range 1..n-1.");
}
Point ret = Point.mul(Point.G, x);
return Point.bytesFromPoint(ret);
}
}

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package schnorr;
import java.math.BigInteger;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
public class Util {
private static final char[] HEX_ARRAY = "0123456789ABCDEF".toCharArray();
public static String bytesToHex(byte[] b) {
char[] hexChars = new char[b.length * 2];
for (int j = 0; j < b.length; j++) {
int v = b[j] & 0xFF;
hexChars[j * 2] = HEX_ARRAY[v >>> 4];
hexChars[j * 2 + 1] = HEX_ARRAY[v & 0x0F];
}
return new String(hexChars);
}
public static byte[] hexToBytes(String s) {
int len = s.length();
byte[] buf = new byte[len / 2];
for (int i = 0; i < len; i += 2) {
buf[i / 2] = (byte)((Character.digit(s.charAt(i), 16) << 4) + Character.digit(s.charAt(i+1), 16));
}
return buf;
}
public static byte[] bytesFromInt(int n) {
return ByteBuffer.allocate(4).order(ByteOrder.BIG_ENDIAN).putInt(n).array();
}
public static byte[] bytesFromBigInteger(BigInteger n) {
byte[] b = n.toByteArray();
if(b.length == 32) {
return b;
}
else if(b.length > 32) {
return Arrays.copyOfRange(b, b.length - 32, b.length);
}
else {
byte[] buf = new byte[32];
System.arraycopy(b, 0, buf, buf.length - b.length, b.length);
return buf;
}
}
public static BigInteger bigIntFromBytes(byte[] b) {
return new BigInteger(1, b);
}
public static byte[] sha256(byte[] b) throws NoSuchAlgorithmException {
MessageDigest digest = MessageDigest.getInstance("SHA-256");
return digest.digest(b);
}
public static byte[] xor(byte[] b0, byte[] b1) {
if(b0.length != b1.length) {
return null;
}
byte[] ret = new byte[b0.length];
int i = 0;
for (byte b : b0) {
ret[i] = (byte)(b ^ b1[i]);
i++;
}
return ret;
}
}