Copied over ref10 sc_reduce replacing crypto_int64 and crypto_uint64 with long

The test fails (likely because all longs are signed in Java)

Author: str4d

src/net/i2p/crypto/eddsa/math/ed25519/Ed25519ScalarOps.java

@@ -0,0 +1,276 @@
+package net.i2p.crypto.eddsa.math.ed25519;
+
+import net.i2p.crypto.eddsa.math.ScalarOps;
+
+public class Ed25519ScalarOps implements ScalarOps {
+    private long load_3(byte[] in, int offset) {
+        long result = in[offset];
+        result |= in[offset + 1] << 8;
+        result |= in[offset + 2] << 16;
+        return result;
+    }
+
+    private long load_4(byte[] in, int offset) {
+        long result = in[offset];
+        result |= in[offset + 1] << 8;
+        result |= in[offset + 2] << 16;
+        result |= in[offset + 3] << 24;
+        return result;
+    }
+
+    /**
+     * Input:<br>
+     *   s[0]+256*s[1]+...+256^63*s[63] = s<br><br>
+     *
+     * Output:<br>
+     *   s[0]+256*s[1]+...+256^31*s[31] = s mod l<br>
+     *   where l = 2^252 + 27742317777372353535851937790883648493.
+     */
+    public byte[] reduce(byte[] s) {
+        long s0 = 2097151 & load_3(s, 0);
+        long s1 = 2097151 & (load_4(s, 2) >> 5);
+        long s2 = 2097151 & (load_3(s, 5) >> 2);
+        long s3 = 2097151 & (load_4(s, 7) >> 7);
+        long s4 = 2097151 & (load_4(s, 10) >> 4);
+        long s5 = 2097151 & (load_3(s, 13) >> 1);
+        long s6 = 2097151 & (load_4(s, 15) >> 6);
+        long s7 = 2097151 & (load_3(s, 18) >> 3);
+        long s8 = 2097151 & load_3(s, 21);
+        long s9 = 2097151 & (load_4(s, 23) >> 5);
+        long s10 = 2097151 & (load_3(s, 26) >> 2);
+        long s11 = 2097151 & (load_4(s, 28) >> 7);
+        long s12 = 2097151 & (load_4(s, 31) >> 4);
+        long s13 = 2097151 & (load_3(s, 34) >> 1);
+        long s14 = 2097151 & (load_4(s, 36) >> 6);
+        long s15 = 2097151 & (load_3(s, 39) >> 3);
+        long s16 = 2097151 & load_3(s, 42);
+        long s17 = 2097151 & (load_4(s, 44) >> 5);
+        long s18 = 2097151 & (load_3(s, 47) >> 2);
+        long s19 = 2097151 & (load_4(s, 49) >> 7);
+        long s20 = 2097151 & (load_4(s, 52) >> 4);
+        long s21 = 2097151 & (load_3(s, 55) >> 1);
+        long s22 = 2097151 & (load_4(s, 57) >> 6);
+        long s23 = (load_4(s, 60) >> 3);
+        long carry0;
+        long carry1;
+        long carry2;
+        long carry3;
+        long carry4;
+        long carry5;
+        long carry6;
+        long carry7;
+        long carry8;
+        long carry9;
+        long carry10;
+        long carry11;
+        long carry12;
+        long carry13;
+        long carry14;
+        long carry15;
+        long carry16;
+
+        s11 += s23 * 666643;
+        s12 += s23 * 470296;
+        s13 += s23 * 654183;
+        s14 -= s23 * 997805;
+        s15 += s23 * 136657;
+        s16 -= s23 * 683901;
+        s23 = 0;
+
+        s10 += s22 * 666643;
+        s11 += s22 * 470296;
+        s12 += s22 * 654183;
+        s13 -= s22 * 997805;
+        s14 += s22 * 136657;
+        s15 -= s22 * 683901;
+        s22 = 0;
+
+        s9 += s21 * 666643;
+        s10 += s21 * 470296;
+        s11 += s21 * 654183;
+        s12 -= s21 * 997805;
+        s13 += s21 * 136657;
+        s14 -= s21 * 683901;
+        s21 = 0;
+
+        s8 += s20 * 666643;
+        s9 += s20 * 470296;
+        s10 += s20 * 654183;
+        s11 -= s20 * 997805;
+        s12 += s20 * 136657;
+        s13 -= s20 * 683901;
+        s20 = 0;
+
+        s7 += s19 * 666643;
+        s8 += s19 * 470296;
+        s9 += s19 * 654183;
+        s10 -= s19 * 997805;
+        s11 += s19 * 136657;
+        s12 -= s19 * 683901;
+        s19 = 0;
+
+        s6 += s18 * 666643;
+        s7 += s18 * 470296;
+        s8 += s18 * 654183;
+        s9 -= s18 * 997805;
+        s10 += s18 * 136657;
+        s11 -= s18 * 683901;
+        s18 = 0;
+
+        carry6 = (s6 + (1<<20)) >> 21; s7 += carry6; s6 -= carry6 << 21;
+        carry8 = (s8 + (1<<20)) >> 21; s9 += carry8; s8 -= carry8 << 21;
+        carry10 = (s10 + (1<<20)) >> 21; s11 += carry10; s10 -= carry10 << 21;
+        carry12 = (s12 + (1<<20)) >> 21; s13 += carry12; s12 -= carry12 << 21;
+        carry14 = (s14 + (1<<20)) >> 21; s15 += carry14; s14 -= carry14 << 21;
+        carry16 = (s16 + (1<<20)) >> 21; s17 += carry16; s16 -= carry16 << 21;
+
+        carry7 = (s7 + (1<<20)) >> 21; s8 += carry7; s7 -= carry7 << 21;
+        carry9 = (s9 + (1<<20)) >> 21; s10 += carry9; s9 -= carry9 << 21;
+        carry11 = (s11 + (1<<20)) >> 21; s12 += carry11; s11 -= carry11 << 21;
+        carry13 = (s13 + (1<<20)) >> 21; s14 += carry13; s13 -= carry13 << 21;
+        carry15 = (s15 + (1<<20)) >> 21; s16 += carry15; s15 -= carry15 << 21;
+
+        s5 += s17 * 666643;
+        s6 += s17 * 470296;
+        s7 += s17 * 654183;
+        s8 -= s17 * 997805;
+        s9 += s17 * 136657;
+        s10 -= s17 * 683901;
+        s17 = 0;
+
+        s4 += s16 * 666643;
+        s5 += s16 * 470296;
+        s6 += s16 * 654183;
+        s7 -= s16 * 997805;
+        s8 += s16 * 136657;
+        s9 -= s16 * 683901;
+        s16 = 0;
+
+        s3 += s15 * 666643;
+        s4 += s15 * 470296;
+        s5 += s15 * 654183;
+        s6 -= s15 * 997805;
+        s7 += s15 * 136657;
+        s8 -= s15 * 683901;
+        s15 = 0;
+
+        s2 += s14 * 666643;
+        s3 += s14 * 470296;
+        s4 += s14 * 654183;
+        s5 -= s14 * 997805;
+        s6 += s14 * 136657;
+        s7 -= s14 * 683901;
+        s14 = 0;
+
+        s1 += s13 * 666643;
+        s2 += s13 * 470296;
+        s3 += s13 * 654183;
+        s4 -= s13 * 997805;
+        s5 += s13 * 136657;
+        s6 -= s13 * 683901;
+        s13 = 0;
+
+        s0 += s12 * 666643;
+        s1 += s12 * 470296;
+        s2 += s12 * 654183;
+        s3 -= s12 * 997805;
+        s4 += s12 * 136657;
+        s5 -= s12 * 683901;
+        s12 = 0;
+
+        carry0 = (s0 + (1<<20)) >> 21; s1 += carry0; s0 -= carry0 << 21;
+        carry2 = (s2 + (1<<20)) >> 21; s3 += carry2; s2 -= carry2 << 21;
+        carry4 = (s4 + (1<<20)) >> 21; s5 += carry4; s4 -= carry4 << 21;
+        carry6 = (s6 + (1<<20)) >> 21; s7 += carry6; s6 -= carry6 << 21;
+        carry8 = (s8 + (1<<20)) >> 21; s9 += carry8; s8 -= carry8 << 21;
+        carry10 = (s10 + (1<<20)) >> 21; s11 += carry10; s10 -= carry10 << 21;
+
+        carry1 = (s1 + (1<<20)) >> 21; s2 += carry1; s1 -= carry1 << 21;
+        carry3 = (s3 + (1<<20)) >> 21; s4 += carry3; s3 -= carry3 << 21;
+        carry5 = (s5 + (1<<20)) >> 21; s6 += carry5; s5 -= carry5 << 21;
+        carry7 = (s7 + (1<<20)) >> 21; s8 += carry7; s7 -= carry7 << 21;
+        carry9 = (s9 + (1<<20)) >> 21; s10 += carry9; s9 -= carry9 << 21;
+        carry11 = (s11 + (1<<20)) >> 21; s12 += carry11; s11 -= carry11 << 21;
+
+        s0 += s12 * 666643;
+        s1 += s12 * 470296;
+        s2 += s12 * 654183;
+        s3 -= s12 * 997805;
+        s4 += s12 * 136657;
+        s5 -= s12 * 683901;
+        s12 = 0;
+
+        carry0 = s0 >> 21; s1 += carry0; s0 -= carry0 << 21;
+        carry1 = s1 >> 21; s2 += carry1; s1 -= carry1 << 21;
+        carry2 = s2 >> 21; s3 += carry2; s2 -= carry2 << 21;
+        carry3 = s3 >> 21; s4 += carry3; s3 -= carry3 << 21;
+        carry4 = s4 >> 21; s5 += carry4; s4 -= carry4 << 21;
+        carry5 = s5 >> 21; s6 += carry5; s5 -= carry5 << 21;
+        carry6 = s6 >> 21; s7 += carry6; s6 -= carry6 << 21;
+        carry7 = s7 >> 21; s8 += carry7; s7 -= carry7 << 21;
+        carry8 = s8 >> 21; s9 += carry8; s8 -= carry8 << 21;
+        carry9 = s9 >> 21; s10 += carry9; s9 -= carry9 << 21;
+        carry10 = s10 >> 21; s11 += carry10; s10 -= carry10 << 21;
+        carry11 = s11 >> 21; s12 += carry11; s11 -= carry11 << 21;
+
+        s0 += s12 * 666643;
+        s1 += s12 * 470296;
+        s2 += s12 * 654183;
+        s3 -= s12 * 997805;
+        s4 += s12 * 136657;
+        s5 -= s12 * 683901;
+        s12 = 0;
+
+        carry0 = s0 >> 21; s1 += carry0; s0 -= carry0 << 21;
+        carry1 = s1 >> 21; s2 += carry1; s1 -= carry1 << 21;
+        carry2 = s2 >> 21; s3 += carry2; s2 -= carry2 << 21;
+        carry3 = s3 >> 21; s4 += carry3; s3 -= carry3 << 21;
+        carry4 = s4 >> 21; s5 += carry4; s4 -= carry4 << 21;
+        carry5 = s5 >> 21; s6 += carry5; s5 -= carry5 << 21;
+        carry6 = s6 >> 21; s7 += carry6; s6 -= carry6 << 21;
+        carry7 = s7 >> 21; s8 += carry7; s7 -= carry7 << 21;
+        carry8 = s8 >> 21; s9 += carry8; s8 -= carry8 << 21;
+        carry9 = s9 >> 21; s10 += carry9; s9 -= carry9 << 21;
+        carry10 = s10 >> 21; s11 += carry10; s10 -= carry10 << 21;
+
+        byte[] result = new byte[32];
+        result[0] = (byte) (s0 >> 0);
+        result[1] = (byte) (s0 >> 8);
+        result[2] = (byte) ((s0 >> 16) | (s1 << 5));
+        result[3] = (byte) (s1 >> 3);
+        result[4] = (byte) (s1 >> 11);
+        result[5] = (byte) ((s1 >> 19) | (s2 << 2));
+        result[6] = (byte) (s2 >> 6);
+        result[7] = (byte) ((s2 >> 14) | (s3 << 7));
+        result[8] = (byte) (s3 >> 1);
+        result[9] = (byte) (s3 >> 9);
+        result[10] = (byte) ((s3 >> 17) | (s4 << 4));
+        result[11] = (byte) (s4 >> 4);
+        result[12] = (byte) (s4 >> 12);
+        result[13] = (byte) ((s4 >> 20) | (s5 << 1));
+        result[14] = (byte) (s5 >> 7);
+        result[15] = (byte) ((s5 >> 15) | (s6 << 6));
+        result[16] = (byte) (s6 >> 2);
+        result[17] = (byte) (s6 >> 10);
+        result[18] = (byte) ((s6 >> 18) | (s7 << 3));
+        result[19] = (byte) (s7 >> 5);
+        result[20] = (byte) (s7 >> 13);
+        result[21] = (byte) (s8 >> 0);
+        result[22] = (byte) (s8 >> 8);
+        result[23] = (byte) ((s8 >> 16) | (s9 << 5));
+        result[24] = (byte) (s9 >> 3);
+        result[25] = (byte) (s9 >> 11);
+        result[26] = (byte) ((s9 >> 19) | (s10 << 2));
+        result[27] = (byte) (s10 >> 6);
+        result[28] = (byte) ((s10 >> 14) | (s11 << 7));
+        result[29] = (byte) (s11 >> 1);
+        result[30] = (byte) (s11 >> 9);
+        result[31] = (byte) (s11 >> 17);
+        return result;
+    }
+
+    public byte[] multiplyAndAdd(byte[] a, byte[] b, byte[] c) {
+        // TODO Auto-generated method stub
+        return null;
+    }
+}

test/net/i2p/crypto/eddsa/math/ed25519/Ed25519ScalarOpsTest.java

@@ -0,0 +1,37 @@
+/**
+ * 
+ */
+package net.i2p.crypto.eddsa.math.ed25519;
+
+import static org.hamcrest.Matchers.*;
+import static org.junit.Assert.*;
+
+import net.i2p.crypto.eddsa.Utils;
+import net.i2p.crypto.eddsa.math.ScalarOps;
+import org.junit.Test;
+
+/**
+ * @author str4d
+ *
+ */
+public class Ed25519ScalarOpsTest {
+    /**
+     * Test method for {@link net.i2p.crypto.eddsa.math.bigint.BigIntegerScalarOps#reduce(byte[])}.
+     */
+    @Test
+    public void testReduce() {
+        ScalarOps sc = new Ed25519ScalarOps();
+        // Example from test case 1
+        byte[] r = Utils.hexToBytes("b6b19cd8e0426f5983fa112d89a143aa97dab8bc5deb8d5b6253c928b65272f4044098c2a990039cde5b6a4818df0bfb6e40dc5dee54248032962323e701352d");
+        assertThat(sc.reduce(r), is(equalTo(Utils.hexToBytes("f38907308c893deaf244787db4af53682249107418afc2edc58f75ac58a07404"))));
+    }
+
+    /**
+     * Test method for {@link net.i2p.crypto.eddsa.math.bigint.BigIntegerScalarOps#multiplyAndAdd(byte[], byte[], byte[])}.
+     */
+    @Test
+    public void testMultiplyAndAdd() {
+        fail("Not yet implemented");
+    }
+
+}