consensus, core/*, params: metropolis preparation refactor

This commit is a preparation for the upcoming metropolis hardfork. It
prepares the state, core and vm packages such that integration with
metropolis becomes less of a hassle.

* Difficulty calculation requires header instead of individual
  parameters
* statedb.StartRecord renamed to statedb.Prepare and added Finalise
  method required by metropolis, which removes unwanted accounts from
  the state (i.e. selfdestruct)
* State keeps record of destructed objects (in addition to dirty
  objects)
* core/vm pre-compiles may now return errors
* core/vm pre-compiles gas check now take the full byte slice as argument
  instead of just the size
* core/vm now keeps several hard-fork instruction tables instead of a
  single instruction table and removes the need for hard-fork checks in
  the instructions
* core/vm contains a empty restruction function which is added in
  preparation of metropolis write-only mode operations
* Adds the bn256 curve
* Adds and sets the metropolis chain config block parameters (2^64-1)

1 files changed, 304 insertions, 0 deletions

diff --git a/crypto/bn256/bn256_test.go b/crypto/bn256/bn256_test.go
new file mode 100644
index 000000000..866065d0c
--- /dev/null
+++ b/crypto/bn256/bn256_test.go
@@ -0,0 +1,304 @@
+// Copyright 2012 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package bn256
+
+import (
+	"bytes"
+	"crypto/rand"
+	"math/big"
+	"testing"
+)
+
+func TestGFp2Invert(t *testing.T) {
+	pool := new(bnPool)
+
+	a := newGFp2(pool)
+	a.x.SetString("23423492374", 10)
+	a.y.SetString("12934872398472394827398470", 10)
+
+	inv := newGFp2(pool)
+	inv.Invert(a, pool)
+
+	b := newGFp2(pool).Mul(inv, a, pool)
+	if b.x.Int64() != 0 || b.y.Int64() != 1 {
+		t.Fatalf("bad result for a^-1*a: %s %s", b.x, b.y)
+	}
+
+	a.Put(pool)
+	b.Put(pool)
+	inv.Put(pool)
+
+	if c := pool.Count(); c > 0 {
+		t.Errorf("Pool count non-zero: %d\n", c)
+	}
+}
+
+func isZero(n *big.Int) bool {
+	return new(big.Int).Mod(n, P).Int64() == 0
+}
+
+func isOne(n *big.Int) bool {
+	return new(big.Int).Mod(n, P).Int64() == 1
+}
+
+func TestGFp6Invert(t *testing.T) {
+	pool := new(bnPool)
+
+	a := newGFp6(pool)
+	a.x.x.SetString("239487238491", 10)
+	a.x.y.SetString("2356249827341", 10)
+	a.y.x.SetString("082659782", 10)
+	a.y.y.SetString("182703523765", 10)
+	a.z.x.SetString("978236549263", 10)
+	a.z.y.SetString("64893242", 10)
+
+	inv := newGFp6(pool)
+	inv.Invert(a, pool)
+
+	b := newGFp6(pool).Mul(inv, a, pool)
+	if !isZero(b.x.x) ||
+		!isZero(b.x.y) ||
+		!isZero(b.y.x) ||
+		!isZero(b.y.y) ||
+		!isZero(b.z.x) ||
+		!isOne(b.z.y) {
+		t.Fatalf("bad result for a^-1*a: %s", b)
+	}
+
+	a.Put(pool)
+	b.Put(pool)
+	inv.Put(pool)
+
+	if c := pool.Count(); c > 0 {
+		t.Errorf("Pool count non-zero: %d\n", c)
+	}
+}
+
+func TestGFp12Invert(t *testing.T) {
+	pool := new(bnPool)
+
+	a := newGFp12(pool)
+	a.x.x.x.SetString("239846234862342323958623", 10)
+	a.x.x.y.SetString("2359862352529835623", 10)
+	a.x.y.x.SetString("928836523", 10)
+	a.x.y.y.SetString("9856234", 10)
+	a.x.z.x.SetString("235635286", 10)
+	a.x.z.y.SetString("5628392833", 10)
+	a.y.x.x.SetString("252936598265329856238956532167968", 10)
+	a.y.x.y.SetString("23596239865236954178968", 10)
+	a.y.y.x.SetString("95421692834", 10)
+	a.y.y.y.SetString("236548", 10)
+	a.y.z.x.SetString("924523", 10)
+	a.y.z.y.SetString("12954623", 10)
+
+	inv := newGFp12(pool)
+	inv.Invert(a, pool)
+
+	b := newGFp12(pool).Mul(inv, a, pool)
+	if !isZero(b.x.x.x) ||
+		!isZero(b.x.x.y) ||
+		!isZero(b.x.y.x) ||
+		!isZero(b.x.y.y) ||
+		!isZero(b.x.z.x) ||
+		!isZero(b.x.z.y) ||
+		!isZero(b.y.x.x) ||
+		!isZero(b.y.x.y) ||
+		!isZero(b.y.y.x) ||
+		!isZero(b.y.y.y) ||
+		!isZero(b.y.z.x) ||
+		!isOne(b.y.z.y) {
+		t.Fatalf("bad result for a^-1*a: %s", b)
+	}
+
+	a.Put(pool)
+	b.Put(pool)
+	inv.Put(pool)
+
+	if c := pool.Count(); c > 0 {
+		t.Errorf("Pool count non-zero: %d\n", c)
+	}
+}
+
+func TestCurveImpl(t *testing.T) {
+	pool := new(bnPool)
+
+	g := &curvePoint{
+		pool.Get().SetInt64(1),
+		pool.Get().SetInt64(-2),
+		pool.Get().SetInt64(1),
+		pool.Get().SetInt64(0),
+	}
+
+	x := pool.Get().SetInt64(32498273234)
+	X := newCurvePoint(pool).Mul(g, x, pool)
+
+	y := pool.Get().SetInt64(98732423523)
+	Y := newCurvePoint(pool).Mul(g, y, pool)
+
+	s1 := newCurvePoint(pool).Mul(X, y, pool).MakeAffine(pool)
+	s2 := newCurvePoint(pool).Mul(Y, x, pool).MakeAffine(pool)
+
+	if s1.x.Cmp(s2.x) != 0 ||
+		s2.x.Cmp(s1.x) != 0 {
+		t.Errorf("DH points don't match: (%s, %s) (%s, %s)", s1.x, s1.y, s2.x, s2.y)
+	}
+
+	pool.Put(x)
+	X.Put(pool)
+	pool.Put(y)
+	Y.Put(pool)
+	s1.Put(pool)
+	s2.Put(pool)
+	g.Put(pool)
+
+	if c := pool.Count(); c > 0 {
+		t.Errorf("Pool count non-zero: %d\n", c)
+	}
+}
+
+func TestOrderG1(t *testing.T) {
+	g := new(G1).ScalarBaseMult(Order)
+	if !g.p.IsInfinity() {
+		t.Error("G1 has incorrect order")
+	}
+
+	one := new(G1).ScalarBaseMult(new(big.Int).SetInt64(1))
+	g.Add(g, one)
+	g.p.MakeAffine(nil)
+	if g.p.x.Cmp(one.p.x) != 0 || g.p.y.Cmp(one.p.y) != 0 {
+		t.Errorf("1+0 != 1 in G1")
+	}
+}
+
+func TestOrderG2(t *testing.T) {
+	g := new(G2).ScalarBaseMult(Order)
+	if !g.p.IsInfinity() {
+		t.Error("G2 has incorrect order")
+	}
+
+	one := new(G2).ScalarBaseMult(new(big.Int).SetInt64(1))
+	g.Add(g, one)
+	g.p.MakeAffine(nil)
+	if g.p.x.x.Cmp(one.p.x.x) != 0 ||
+		g.p.x.y.Cmp(one.p.x.y) != 0 ||
+		g.p.y.x.Cmp(one.p.y.x) != 0 ||
+		g.p.y.y.Cmp(one.p.y.y) != 0 {
+		t.Errorf("1+0 != 1 in G2")
+	}
+}
+
+func TestOrderGT(t *testing.T) {
+	gt := Pair(&G1{curveGen}, &G2{twistGen})
+	g := new(GT).ScalarMult(gt, Order)
+	if !g.p.IsOne() {
+		t.Error("GT has incorrect order")
+	}
+}
+
+func TestBilinearity(t *testing.T) {
+	for i := 0; i < 2; i++ {
+		a, p1, _ := RandomG1(rand.Reader)
+		b, p2, _ := RandomG2(rand.Reader)
+		e1 := Pair(p1, p2)
+
+		e2 := Pair(&G1{curveGen}, &G2{twistGen})
+		e2.ScalarMult(e2, a)
+		e2.ScalarMult(e2, b)
+
+		minusE2 := new(GT).Neg(e2)
+		e1.Add(e1, minusE2)
+
+		if !e1.p.IsOne() {
+			t.Fatalf("bad pairing result: %s", e1)
+		}
+	}
+}
+
+func TestG1Marshal(t *testing.T) {
+	g := new(G1).ScalarBaseMult(new(big.Int).SetInt64(1))
+	form := g.Marshal()
+	_, ok := new(G1).Unmarshal(form)
+	if !ok {
+		t.Fatalf("failed to unmarshal")
+	}
+
+	g.ScalarBaseMult(Order)
+	form = g.Marshal()
+	g2, ok := new(G1).Unmarshal(form)
+	if !ok {
+		t.Fatalf("failed to unmarshal ∞")
+	}
+	if !g2.p.IsInfinity() {
+		t.Fatalf("∞ unmarshaled incorrectly")
+	}
+}
+
+func TestG2Marshal(t *testing.T) {
+	g := new(G2).ScalarBaseMult(new(big.Int).SetInt64(1))
+	form := g.Marshal()
+	_, ok := new(G2).Unmarshal(form)
+	if !ok {
+		t.Fatalf("failed to unmarshal")
+	}
+
+	g.ScalarBaseMult(Order)
+	form = g.Marshal()
+	g2, ok := new(G2).Unmarshal(form)
+	if !ok {
+		t.Fatalf("failed to unmarshal ∞")
+	}
+	if !g2.p.IsInfinity() {
+		t.Fatalf("∞ unmarshaled incorrectly")
+	}
+}
+
+func TestG1Identity(t *testing.T) {
+	g := new(G1).ScalarBaseMult(new(big.Int).SetInt64(0))
+	if !g.p.IsInfinity() {
+		t.Error("failure")
+	}
+}
+
+func TestG2Identity(t *testing.T) {
+	g := new(G2).ScalarBaseMult(new(big.Int).SetInt64(0))
+	if !g.p.IsInfinity() {
+		t.Error("failure")
+	}
+}
+
+func TestTripartiteDiffieHellman(t *testing.T) {
+	a, _ := rand.Int(rand.Reader, Order)
+	b, _ := rand.Int(rand.Reader, Order)
+	c, _ := rand.Int(rand.Reader, Order)
+
+	pa, _ := new(G1).Unmarshal(new(G1).ScalarBaseMult(a).Marshal())
+	qa, _ := new(G2).Unmarshal(new(G2).ScalarBaseMult(a).Marshal())
+	pb, _ := new(G1).Unmarshal(new(G1).ScalarBaseMult(b).Marshal())
+	qb, _ := new(G2).Unmarshal(new(G2).ScalarBaseMult(b).Marshal())
+	pc, _ := new(G1).Unmarshal(new(G1).ScalarBaseMult(c).Marshal())
+	qc, _ := new(G2).Unmarshal(new(G2).ScalarBaseMult(c).Marshal())
+
+	k1 := Pair(pb, qc)
+	k1.ScalarMult(k1, a)
+	k1Bytes := k1.Marshal()
+
+	k2 := Pair(pc, qa)
+	k2.ScalarMult(k2, b)
+	k2Bytes := k2.Marshal()
+
+	k3 := Pair(pa, qb)
+	k3.ScalarMult(k3, c)
+	k3Bytes := k3.Marshal()
+
+	if !bytes.Equal(k1Bytes, k2Bytes) || !bytes.Equal(k2Bytes, k3Bytes) {
+		t.Errorf("keys didn't agree")
+	}
+}
+
+func BenchmarkPairing(b *testing.B) {
+	for i := 0; i < b.N; i++ {
+		Pair(&G1{curveGen}, &G2{twistGen})
+	}
+}