Imported Upstream version 1.4upstream/1.4

5 files changed, 0 insertions, 2829 deletions

diff --git a/src/pkg/crypto/elliptic/elliptic.go b/src/pkg/crypto/elliptic/elliptic.go
deleted file mode 100644
index ba673f80c..000000000
--- a/src/pkg/crypto/elliptic/elliptic.go
+++ /dev/null
@@ -1,373 +0,0 @@
-// Copyright 2010 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 elliptic implements several standard elliptic curves over prime
-// fields.
-package elliptic
-
-// This package operates, internally, on Jacobian coordinates. For a given
-// (x, y) position on the curve, the Jacobian coordinates are (x1, y1, z1)
-// where x = x1/z1² and y = y1/z1³. The greatest speedups come when the whole
-// calculation can be performed within the transform (as in ScalarMult and
-// ScalarBaseMult). But even for Add and Double, it's faster to apply and
-// reverse the transform than to operate in affine coordinates.
-
-import (
-	"io"
-	"math/big"
-	"sync"
-)
-
-// A Curve represents a short-form Weierstrass curve with a=-3.
-// See http://www.hyperelliptic.org/EFD/g1p/auto-shortw.html
-type Curve interface {
-	// Params returns the parameters for the curve.
-	Params() *CurveParams
-	// IsOnCurve returns true if the given (x,y) lies on the curve.
-	IsOnCurve(x, y *big.Int) bool
-	// Add returns the sum of (x1,y1) and (x2,y2)
-	Add(x1, y1, x2, y2 *big.Int) (x, y *big.Int)
-	// Double returns 2*(x,y)
-	Double(x1, y1 *big.Int) (x, y *big.Int)
-	// ScalarMult returns k*(Bx,By) where k is a number in big-endian form.
-	ScalarMult(x1, y1 *big.Int, k []byte) (x, y *big.Int)
-	// ScalarBaseMult returns k*G, where G is the base point of the group
-	// and k is an integer in big-endian form.
-	ScalarBaseMult(k []byte) (x, y *big.Int)
-}
-
-// CurveParams contains the parameters of an elliptic curve and also provides
-// a generic, non-constant time implementation of Curve.
-type CurveParams struct {
-	P       *big.Int // the order of the underlying field
-	N       *big.Int // the order of the base point
-	B       *big.Int // the constant of the curve equation
-	Gx, Gy  *big.Int // (x,y) of the base point
-	BitSize int      // the size of the underlying field
-}
-
-func (curve *CurveParams) Params() *CurveParams {
-	return curve
-}
-
-func (curve *CurveParams) IsOnCurve(x, y *big.Int) bool {
-	// y² = x³ - 3x + b
-	y2 := new(big.Int).Mul(y, y)
-	y2.Mod(y2, curve.P)
-
-	x3 := new(big.Int).Mul(x, x)
-	x3.Mul(x3, x)
-
-	threeX := new(big.Int).Lsh(x, 1)
-	threeX.Add(threeX, x)
-
-	x3.Sub(x3, threeX)
-	x3.Add(x3, curve.B)
-	x3.Mod(x3, curve.P)
-
-	return x3.Cmp(y2) == 0
-}
-
-// zForAffine returns a Jacobian Z value for the affine point (x, y). If x and
-// y are zero, it assumes that they represent the point at infinity because (0,
-// 0) is not on the any of the curves handled here.
-func zForAffine(x, y *big.Int) *big.Int {
-	z := new(big.Int)
-	if x.Sign() != 0 || y.Sign() != 0 {
-		z.SetInt64(1)
-	}
-	return z
-}
-
-// affineFromJacobian reverses the Jacobian transform. See the comment at the
-// top of the file. If the point is ∞ it returns 0, 0.
-func (curve *CurveParams) affineFromJacobian(x, y, z *big.Int) (xOut, yOut *big.Int) {
-	if z.Sign() == 0 {
-		return new(big.Int), new(big.Int)
-	}
-
-	zinv := new(big.Int).ModInverse(z, curve.P)
-	zinvsq := new(big.Int).Mul(zinv, zinv)
-
-	xOut = new(big.Int).Mul(x, zinvsq)
-	xOut.Mod(xOut, curve.P)
-	zinvsq.Mul(zinvsq, zinv)
-	yOut = new(big.Int).Mul(y, zinvsq)
-	yOut.Mod(yOut, curve.P)
-	return
-}
-
-func (curve *CurveParams) Add(x1, y1, x2, y2 *big.Int) (*big.Int, *big.Int) {
-	z1 := zForAffine(x1, y1)
-	z2 := zForAffine(x2, y2)
-	return curve.affineFromJacobian(curve.addJacobian(x1, y1, z1, x2, y2, z2))
-}
-
-// addJacobian takes two points in Jacobian coordinates, (x1, y1, z1) and
-// (x2, y2, z2) and returns their sum, also in Jacobian form.
-func (curve *CurveParams) addJacobian(x1, y1, z1, x2, y2, z2 *big.Int) (*big.Int, *big.Int, *big.Int) {
-	// See http://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#addition-add-2007-bl
-	x3, y3, z3 := new(big.Int), new(big.Int), new(big.Int)
-	if z1.Sign() == 0 {
-		x3.Set(x2)
-		y3.Set(y2)
-		z3.Set(z2)
-		return x3, y3, z3
-	}
-	if z2.Sign() == 0 {
-		x3.Set(x1)
-		y3.Set(y1)
-		z3.Set(z1)
-		return x3, y3, z3
-	}
-
-	z1z1 := new(big.Int).Mul(z1, z1)
-	z1z1.Mod(z1z1, curve.P)
-	z2z2 := new(big.Int).Mul(z2, z2)
-	z2z2.Mod(z2z2, curve.P)
-
-	u1 := new(big.Int).Mul(x1, z2z2)
-	u1.Mod(u1, curve.P)
-	u2 := new(big.Int).Mul(x2, z1z1)
-	u2.Mod(u2, curve.P)
-	h := new(big.Int).Sub(u2, u1)
-	xEqual := h.Sign() == 0
-	if h.Sign() == -1 {
-		h.Add(h, curve.P)
-	}
-	i := new(big.Int).Lsh(h, 1)
-	i.Mul(i, i)
-	j := new(big.Int).Mul(h, i)
-
-	s1 := new(big.Int).Mul(y1, z2)
-	s1.Mul(s1, z2z2)
-	s1.Mod(s1, curve.P)
-	s2 := new(big.Int).Mul(y2, z1)
-	s2.Mul(s2, z1z1)
-	s2.Mod(s2, curve.P)
-	r := new(big.Int).Sub(s2, s1)
-	if r.Sign() == -1 {
-		r.Add(r, curve.P)
-	}
-	yEqual := r.Sign() == 0
-	if xEqual && yEqual {
-		return curve.doubleJacobian(x1, y1, z1)
-	}
-	r.Lsh(r, 1)
-	v := new(big.Int).Mul(u1, i)
-
-	x3.Set(r)
-	x3.Mul(x3, x3)
-	x3.Sub(x3, j)
-	x3.Sub(x3, v)
-	x3.Sub(x3, v)
-	x3.Mod(x3, curve.P)
-
-	y3.Set(r)
-	v.Sub(v, x3)
-	y3.Mul(y3, v)
-	s1.Mul(s1, j)
-	s1.Lsh(s1, 1)
-	y3.Sub(y3, s1)
-	y3.Mod(y3, curve.P)
-
-	z3.Add(z1, z2)
-	z3.Mul(z3, z3)
-	z3.Sub(z3, z1z1)
-	z3.Sub(z3, z2z2)
-	z3.Mul(z3, h)
-	z3.Mod(z3, curve.P)
-
-	return x3, y3, z3
-}
-
-func (curve *CurveParams) Double(x1, y1 *big.Int) (*big.Int, *big.Int) {
-	z1 := zForAffine(x1, y1)
-	return curve.affineFromJacobian(curve.doubleJacobian(x1, y1, z1))
-}
-
-// doubleJacobian takes a point in Jacobian coordinates, (x, y, z), and
-// returns its double, also in Jacobian form.
-func (curve *CurveParams) doubleJacobian(x, y, z *big.Int) (*big.Int, *big.Int, *big.Int) {
-	// See http://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#doubling-dbl-2001-b
-	delta := new(big.Int).Mul(z, z)
-	delta.Mod(delta, curve.P)
-	gamma := new(big.Int).Mul(y, y)
-	gamma.Mod(gamma, curve.P)
-	alpha := new(big.Int).Sub(x, delta)
-	if alpha.Sign() == -1 {
-		alpha.Add(alpha, curve.P)
-	}
-	alpha2 := new(big.Int).Add(x, delta)
-	alpha.Mul(alpha, alpha2)
-	alpha2.Set(alpha)
-	alpha.Lsh(alpha, 1)
-	alpha.Add(alpha, alpha2)
-
-	beta := alpha2.Mul(x, gamma)
-
-	x3 := new(big.Int).Mul(alpha, alpha)
-	beta8 := new(big.Int).Lsh(beta, 3)
-	x3.Sub(x3, beta8)
-	for x3.Sign() == -1 {
-		x3.Add(x3, curve.P)
-	}
-	x3.Mod(x3, curve.P)
-
-	z3 := new(big.Int).Add(y, z)
-	z3.Mul(z3, z3)
-	z3.Sub(z3, gamma)
-	if z3.Sign() == -1 {
-		z3.Add(z3, curve.P)
-	}
-	z3.Sub(z3, delta)
-	if z3.Sign() == -1 {
-		z3.Add(z3, curve.P)
-	}
-	z3.Mod(z3, curve.P)
-
-	beta.Lsh(beta, 2)
-	beta.Sub(beta, x3)
-	if beta.Sign() == -1 {
-		beta.Add(beta, curve.P)
-	}
-	y3 := alpha.Mul(alpha, beta)
-
-	gamma.Mul(gamma, gamma)
-	gamma.Lsh(gamma, 3)
-	gamma.Mod(gamma, curve.P)
-
-	y3.Sub(y3, gamma)
-	if y3.Sign() == -1 {
-		y3.Add(y3, curve.P)
-	}
-	y3.Mod(y3, curve.P)
-
-	return x3, y3, z3
-}
-
-func (curve *CurveParams) ScalarMult(Bx, By *big.Int, k []byte) (*big.Int, *big.Int) {
-	Bz := new(big.Int).SetInt64(1)
-	x, y, z := new(big.Int), new(big.Int), new(big.Int)
-
-	for _, byte := range k {
-		for bitNum := 0; bitNum < 8; bitNum++ {
-			x, y, z = curve.doubleJacobian(x, y, z)
-			if byte&0x80 == 0x80 {
-				x, y, z = curve.addJacobian(Bx, By, Bz, x, y, z)
-			}
-			byte <<= 1
-		}
-	}
-
-	return curve.affineFromJacobian(x, y, z)
-}
-
-func (curve *CurveParams) ScalarBaseMult(k []byte) (*big.Int, *big.Int) {
-	return curve.ScalarMult(curve.Gx, curve.Gy, k)
-}
-
-var mask = []byte{0xff, 0x1, 0x3, 0x7, 0xf, 0x1f, 0x3f, 0x7f}
-
-// GenerateKey returns a public/private key pair. The private key is
-// generated using the given reader, which must return random data.
-func GenerateKey(curve Curve, rand io.Reader) (priv []byte, x, y *big.Int, err error) {
-	bitSize := curve.Params().BitSize
-	byteLen := (bitSize + 7) >> 3
-	priv = make([]byte, byteLen)
-
-	for x == nil {
-		_, err = io.ReadFull(rand, priv)
-		if err != nil {
-			return
-		}
-		// We have to mask off any excess bits in the case that the size of the
-		// underlying field is not a whole number of bytes.
-		priv[0] &= mask[bitSize%8]
-		// This is because, in tests, rand will return all zeros and we don't
-		// want to get the point at infinity and loop forever.
-		priv[1] ^= 0x42
-		x, y = curve.ScalarBaseMult(priv)
-	}
-	return
-}
-
-// Marshal converts a point into the form specified in section 4.3.6 of ANSI X9.62.
-func Marshal(curve Curve, x, y *big.Int) []byte {
-	byteLen := (curve.Params().BitSize + 7) >> 3
-
-	ret := make([]byte, 1+2*byteLen)
-	ret[0] = 4 // uncompressed point
-
-	xBytes := x.Bytes()
-	copy(ret[1+byteLen-len(xBytes):], xBytes)
-	yBytes := y.Bytes()
-	copy(ret[1+2*byteLen-len(yBytes):], yBytes)
-	return ret
-}
-
-// Unmarshal converts a point, serialized by Marshal, into an x, y pair. On error, x = nil.
-func Unmarshal(curve Curve, data []byte) (x, y *big.Int) {
-	byteLen := (curve.Params().BitSize + 7) >> 3
-	if len(data) != 1+2*byteLen {
-		return
-	}
-	if data[0] != 4 { // uncompressed form
-		return
-	}
-	x = new(big.Int).SetBytes(data[1 : 1+byteLen])
-	y = new(big.Int).SetBytes(data[1+byteLen:])
-	return
-}
-
-var initonce sync.Once
-var p384 *CurveParams
-var p521 *CurveParams
-
-func initAll() {
-	initP224()
-	initP256()
-	initP384()
-	initP521()
-}
-
-func initP384() {
-	// See FIPS 186-3, section D.2.4
-	p384 = new(CurveParams)
-	p384.P, _ = new(big.Int).SetString("39402006196394479212279040100143613805079739270465446667948293404245721771496870329047266088258938001861606973112319", 10)
-	p384.N, _ = new(big.Int).SetString("39402006196394479212279040100143613805079739270465446667946905279627659399113263569398956308152294913554433653942643", 10)
-	p384.B, _ = new(big.Int).SetString("b3312fa7e23ee7e4988e056be3f82d19181d9c6efe8141120314088f5013875ac656398d8a2ed19d2a85c8edd3ec2aef", 16)
-	p384.Gx, _ = new(big.Int).SetString("aa87ca22be8b05378eb1c71ef320ad746e1d3b628ba79b9859f741e082542a385502f25dbf55296c3a545e3872760ab7", 16)
-	p384.Gy, _ = new(big.Int).SetString("3617de4a96262c6f5d9e98bf9292dc29f8f41dbd289a147ce9da3113b5f0b8c00a60b1ce1d7e819d7a431d7c90ea0e5f", 16)
-	p384.BitSize = 384
-}
-
-func initP521() {
-	// See FIPS 186-3, section D.2.5
-	p521 = new(CurveParams)
-	p521.P, _ = new(big.Int).SetString("6864797660130609714981900799081393217269435300143305409394463459185543183397656052122559640661454554977296311391480858037121987999716643812574028291115057151", 10)
-	p521.N, _ = new(big.Int).SetString("6864797660130609714981900799081393217269435300143305409394463459185543183397655394245057746333217197532963996371363321113864768612440380340372808892707005449", 10)
-	p521.B, _ = new(big.Int).SetString("051953eb9618e1c9a1f929a21a0b68540eea2da725b99b315f3b8b489918ef109e156193951ec7e937b1652c0bd3bb1bf073573df883d2c34f1ef451fd46b503f00", 16)
-	p521.Gx, _ = new(big.Int).SetString("c6858e06b70404e9cd9e3ecb662395b4429c648139053fb521f828af606b4d3dbaa14b5e77efe75928fe1dc127a2ffa8de3348b3c1856a429bf97e7e31c2e5bd66", 16)
-	p521.Gy, _ = new(big.Int).SetString("11839296a789a3bc0045c8a5fb42c7d1bd998f54449579b446817afbd17273e662c97ee72995ef42640c550b9013fad0761353c7086a272c24088be94769fd16650", 16)
-	p521.BitSize = 521
-}
-
-// P256 returns a Curve which implements P-256 (see FIPS 186-3, section D.2.3)
-func P256() Curve {
-	initonce.Do(initAll)
-	return p256
-}
-
-// P384 returns a Curve which implements P-384 (see FIPS 186-3, section D.2.4)
-func P384() Curve {
-	initonce.Do(initAll)
-	return p384
-}
-
-// P521 returns a Curve which implements P-521 (see FIPS 186-3, section D.2.5)
-func P521() Curve {
-	initonce.Do(initAll)
-	return p521
-}
diff --git a/src/pkg/crypto/elliptic/elliptic_test.go b/src/pkg/crypto/elliptic/elliptic_test.go
deleted file mode 100644
index 4dc27c92b..000000000
--- a/src/pkg/crypto/elliptic/elliptic_test.go
+++ /dev/null
@@ -1,458 +0,0 @@
-// Copyright 2010 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 elliptic
-
-import (
-	"crypto/rand"
-	"encoding/hex"
-	"fmt"
-	"math/big"
-	"testing"
-)
-
-func TestOnCurve(t *testing.T) {
-	p224 := P224()
-	if !p224.IsOnCurve(p224.Params().Gx, p224.Params().Gy) {
-		t.Errorf("FAIL")
-	}
-}
-
-type baseMultTest struct {
-	k    string
-	x, y string
-}
-
-var p224BaseMultTests = []baseMultTest{
-	{
-		"1",
-		"b70e0cbd6bb4bf7f321390b94a03c1d356c21122343280d6115c1d21",
-		"bd376388b5f723fb4c22dfe6cd4375a05a07476444d5819985007e34",
-	},
-	{
-		"2",
-		"706a46dc76dcb76798e60e6d89474788d16dc18032d268fd1a704fa6",
-		"1c2b76a7bc25e7702a704fa986892849fca629487acf3709d2e4e8bb",
-	},
-	{
-		"3",
-		"df1b1d66a551d0d31eff822558b9d2cc75c2180279fe0d08fd896d04",
-		"a3f7f03cadd0be444c0aa56830130ddf77d317344e1af3591981a925",
-	},
-	{
-		"4",
-		"ae99feebb5d26945b54892092a8aee02912930fa41cd114e40447301",
-		"482580a0ec5bc47e88bc8c378632cd196cb3fa058a7114eb03054c9",
-	},
-	{
-		"5",
-		"31c49ae75bce7807cdff22055d94ee9021fedbb5ab51c57526f011aa",
-		"27e8bff1745635ec5ba0c9f1c2ede15414c6507d29ffe37e790a079b",
-	},
-	{
-		"6",
-		"1f2483f82572251fca975fea40db821df8ad82a3c002ee6c57112408",
-		"89faf0ccb750d99b553c574fad7ecfb0438586eb3952af5b4b153c7e",
-	},
-	{
-		"7",
-		"db2f6be630e246a5cf7d99b85194b123d487e2d466b94b24a03c3e28",
-		"f3a30085497f2f611ee2517b163ef8c53b715d18bb4e4808d02b963",
-	},
-	{
-		"8",
-		"858e6f9cc6c12c31f5df124aa77767b05c8bc021bd683d2b55571550",
-		"46dcd3ea5c43898c5c5fc4fdac7db39c2f02ebee4e3541d1e78047a",
-	},
-	{
-		"9",
-		"2fdcccfee720a77ef6cb3bfbb447f9383117e3daa4a07e36ed15f78d",
-		"371732e4f41bf4f7883035e6a79fcedc0e196eb07b48171697517463",
-	},
-	{
-		"10",
-		"aea9e17a306517eb89152aa7096d2c381ec813c51aa880e7bee2c0fd",
-		"39bb30eab337e0a521b6cba1abe4b2b3a3e524c14a3fe3eb116b655f",
-	},
-	{
-		"11",
-		"ef53b6294aca431f0f3c22dc82eb9050324f1d88d377e716448e507c",
-		"20b510004092e96636cfb7e32efded8265c266dfb754fa6d6491a6da",
-	},
-	{
-		"12",
-		"6e31ee1dc137f81b056752e4deab1443a481033e9b4c93a3044f4f7a",
-		"207dddf0385bfdeab6e9acda8da06b3bbef224a93ab1e9e036109d13",
-	},
-	{
-		"13",
-		"34e8e17a430e43289793c383fac9774247b40e9ebd3366981fcfaeca",
-		"252819f71c7fb7fbcb159be337d37d3336d7feb963724fdfb0ecb767",
-	},
-	{
-		"14",
-		"a53640c83dc208603ded83e4ecf758f24c357d7cf48088b2ce01e9fa",
-		"d5814cd724199c4a5b974a43685fbf5b8bac69459c9469bc8f23ccaf",
-	},
-	{
-		"15",
-		"baa4d8635511a7d288aebeedd12ce529ff102c91f97f867e21916bf9",
-		"979a5f4759f80f4fb4ec2e34f5566d595680a11735e7b61046127989",
-	},
-	{
-		"16",
-		"b6ec4fe1777382404ef679997ba8d1cc5cd8e85349259f590c4c66d",
-		"3399d464345906b11b00e363ef429221f2ec720d2f665d7dead5b482",
-	},
-	{
-		"17",
-		"b8357c3a6ceef288310e17b8bfeff9200846ca8c1942497c484403bc",
-		"ff149efa6606a6bd20ef7d1b06bd92f6904639dce5174db6cc554a26",
-	},
-	{
-		"18",
-		"c9ff61b040874c0568479216824a15eab1a838a797d189746226e4cc",
-		"ea98d60e5ffc9b8fcf999fab1df7e7ef7084f20ddb61bb045a6ce002",
-	},
-	{
-		"19",
-		"a1e81c04f30ce201c7c9ace785ed44cc33b455a022f2acdbc6cae83c",
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-		"20",
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-		"26959946667150639794667015087019625940457807714424391721682722368046",
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-		"26959946667150639794667015087019625940457807714424391721682722368047",
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-		"26959946667150639794667015087019625940457807714424391721682722368049",
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-		"1f2483f82572251fca975fea40db821df8ad82a3c002ee6c57112408",
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-		"26959946667150639794667015087019625940457807714424391721682722368056",
-		"31c49ae75bce7807cdff22055d94ee9021fedbb5ab51c57526f011aa",
-		"d817400e8ba9ca13a45f360e3d121eaaeb39af82d6001c8186f5f866",
-	},
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-		"26959946667150639794667015087019625940457807714424391721682722368057",
-		"ae99feebb5d26945b54892092a8aee02912930fa41cd114e40447301",
-		"fb7da7f5f13a43b81774373c879cd32d6934c05fa758eeb14fcfab38",
-	},
-	{
-		"26959946667150639794667015087019625940457807714424391721682722368058",
-		"df1b1d66a551d0d31eff822558b9d2cc75c2180279fe0d08fd896d04",
-		"5c080fc3522f41bbb3f55a97cfecf21f882ce8cbb1e50ca6e67e56dc",
-	},
-	{
-		"26959946667150639794667015087019625940457807714424391721682722368059",
-		"706a46dc76dcb76798e60e6d89474788d16dc18032d268fd1a704fa6",
-		"e3d4895843da188fd58fb0567976d7b50359d6b78530c8f62d1b1746",
-	},
-	{
-		"26959946667150639794667015087019625940457807714424391721682722368060",
-		"b70e0cbd6bb4bf7f321390b94a03c1d356c21122343280d6115c1d21",
-		"42c89c774a08dc04b3dd201932bc8a5ea5f8b89bbb2a7e667aff81cd",
-	},
-}
-
-func TestBaseMult(t *testing.T) {
-	p224 := P224()
-	for i, e := range p224BaseMultTests {
-		k, ok := new(big.Int).SetString(e.k, 10)
-		if !ok {
-			t.Errorf("%d: bad value for k: %s", i, e.k)
-		}
-		x, y := p224.ScalarBaseMult(k.Bytes())
-		if fmt.Sprintf("%x", x) != e.x || fmt.Sprintf("%x", y) != e.y {
-			t.Errorf("%d: bad output for k=%s: got (%x, %x), want (%s, %s)", i, e.k, x, y, e.x, e.y)
-		}
-		if testing.Short() && i > 5 {
-			break
-		}
-	}
-}
-
-func TestGenericBaseMult(t *testing.T) {
-	// We use the P224 CurveParams directly in order to test the generic implementation.
-	p224 := P224().Params()
-	for i, e := range p224BaseMultTests {
-		k, ok := new(big.Int).SetString(e.k, 10)
-		if !ok {
-			t.Errorf("%d: bad value for k: %s", i, e.k)
-		}
-		x, y := p224.ScalarBaseMult(k.Bytes())
-		if fmt.Sprintf("%x", x) != e.x || fmt.Sprintf("%x", y) != e.y {
-			t.Errorf("%d: bad output for k=%s: got (%x, %x), want (%s, %s)", i, e.k, x, y, e.x, e.y)
-		}
-		if testing.Short() && i > 5 {
-			break
-		}
-	}
-}
-
-func TestP256BaseMult(t *testing.T) {
-	p256 := P256()
-	p256Generic := p256.Params()
-
-	scalars := make([]*big.Int, 0, len(p224BaseMultTests)+1)
-	for _, e := range p224BaseMultTests {
-		k, _ := new(big.Int).SetString(e.k, 10)
-		scalars = append(scalars, k)
-	}
-	k := new(big.Int).SetInt64(1)
-	k.Lsh(k, 500)
-	scalars = append(scalars, k)
-
-	for i, k := range scalars {
-		x, y := p256.ScalarBaseMult(k.Bytes())
-		x2, y2 := p256Generic.ScalarBaseMult(k.Bytes())
-		if x.Cmp(x2) != 0 || y.Cmp(y2) != 0 {
-			t.Errorf("#%d: got (%x, %x), want (%x, %x)", i, x, y, x2, y2)
-		}
-
-		if testing.Short() && i > 5 {
-			break
-		}
-	}
-}
-
-func TestP256Mult(t *testing.T) {
-	p256 := P256()
-	p256Generic := p256.Params()
-
-	for i, e := range p224BaseMultTests {
-		x, _ := new(big.Int).SetString(e.x, 16)
-		y, _ := new(big.Int).SetString(e.y, 16)
-		k, _ := new(big.Int).SetString(e.k, 10)
-
-		xx, yy := p256.ScalarMult(x, y, k.Bytes())
-		xx2, yy2 := p256Generic.ScalarMult(x, y, k.Bytes())
-		if xx.Cmp(xx2) != 0 || yy.Cmp(yy2) != 0 {
-			t.Errorf("#%d: got (%x, %x), want (%x, %x)", i, xx, yy, xx2, yy2)
-		}
-		if testing.Short() && i > 5 {
-			break
-		}
-	}
-}
-
-func TestInfinity(t *testing.T) {
-	tests := []struct {
-		name  string
-		curve Curve
-	}{
-		{"p224", P224()},
-		{"p256", P256()},
-	}
-
-	for _, test := range tests {
-		curve := test.curve
-		x, y := curve.ScalarBaseMult(nil)
-		if x.Sign() != 0 || y.Sign() != 0 {
-			t.Errorf("%s: x^0 != ∞", test.name)
-		}
-		x.SetInt64(0)
-		y.SetInt64(0)
-
-		x2, y2 := curve.Double(x, y)
-		if x2.Sign() != 0 || y2.Sign() != 0 {
-			t.Errorf("%s: 2∞ != ∞", test.name)
-		}
-
-		baseX := curve.Params().Gx
-		baseY := curve.Params().Gy
-
-		x3, y3 := curve.Add(baseX, baseY, x, y)
-		if x3.Cmp(baseX) != 0 || y3.Cmp(baseY) != 0 {
-			t.Errorf("%s: x+∞ != x", test.name)
-		}
-
-		x4, y4 := curve.Add(x, y, baseX, baseY)
-		if x4.Cmp(baseX) != 0 || y4.Cmp(baseY) != 0 {
-			t.Errorf("%s: ∞+x != x", test.name)
-		}
-	}
-}
-
-func BenchmarkBaseMult(b *testing.B) {
-	b.ResetTimer()
-	p224 := P224()
-	e := p224BaseMultTests[25]
-	k, _ := new(big.Int).SetString(e.k, 10)
-	b.StartTimer()
-	for i := 0; i < b.N; i++ {
-		p224.ScalarBaseMult(k.Bytes())
-	}
-}
-
-func BenchmarkBaseMultP256(b *testing.B) {
-	b.ResetTimer()
-	p256 := P256()
-	e := p224BaseMultTests[25]
-	k, _ := new(big.Int).SetString(e.k, 10)
-	b.StartTimer()
-	for i := 0; i < b.N; i++ {
-		p256.ScalarBaseMult(k.Bytes())
-	}
-}
-
-func TestMarshal(t *testing.T) {
-	p224 := P224()
-	_, x, y, err := GenerateKey(p224, rand.Reader)
-	if err != nil {
-		t.Error(err)
-		return
-	}
-	serialized := Marshal(p224, x, y)
-	xx, yy := Unmarshal(p224, serialized)
-	if xx == nil {
-		t.Error("failed to unmarshal")
-		return
-	}
-	if xx.Cmp(x) != 0 || yy.Cmp(y) != 0 {
-		t.Error("unmarshal returned different values")
-		return
-	}
-}
-
-func TestP224Overflow(t *testing.T) {
-	// This tests for a specific bug in the P224 implementation.
-	p224 := P224()
-	pointData, _ := hex.DecodeString("049B535B45FB0A2072398A6831834624C7E32CCFD5A4B933BCEAF77F1DD945E08BBE5178F5EDF5E733388F196D2A631D2E075BB16CBFEEA15B")
-	x, y := Unmarshal(p224, pointData)
-	if !p224.IsOnCurve(x, y) {
-		t.Error("P224 failed to validate a correct point")
-	}
-}
diff --git a/src/pkg/crypto/elliptic/p224.go b/src/pkg/crypto/elliptic/p224.go
deleted file mode 100644
index 1f7ff3f9d..000000000
--- a/src/pkg/crypto/elliptic/p224.go
+++ /dev/null
@@ -1,765 +0,0 @@
-// 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 elliptic
-
-// This is a constant-time, 32-bit implementation of P224. See FIPS 186-3,
-// section D.2.2.
-//
-// See http://www.imperialviolet.org/2010/12/04/ecc.html ([1]) for background.
-
-import (
-	"math/big"
-)
-
-var p224 p224Curve
-
-type p224Curve struct {
-	*CurveParams
-	gx, gy, b p224FieldElement
-}
-
-func initP224() {
-	// See FIPS 186-3, section D.2.2
-	p224.CurveParams = new(CurveParams)
-	p224.P, _ = new(big.Int).SetString("26959946667150639794667015087019630673557916260026308143510066298881", 10)
-	p224.N, _ = new(big.Int).SetString("26959946667150639794667015087019625940457807714424391721682722368061", 10)
-	p224.B, _ = new(big.Int).SetString("b4050a850c04b3abf54132565044b0b7d7bfd8ba270b39432355ffb4", 16)
-	p224.Gx, _ = new(big.Int).SetString("b70e0cbd6bb4bf7f321390b94a03c1d356c21122343280d6115c1d21", 16)
-	p224.Gy, _ = new(big.Int).SetString("bd376388b5f723fb4c22dfe6cd4375a05a07476444d5819985007e34", 16)
-	p224.BitSize = 224
-
-	p224FromBig(&p224.gx, p224.Gx)
-	p224FromBig(&p224.gy, p224.Gy)
-	p224FromBig(&p224.b, p224.B)
-}
-
-// P224 returns a Curve which implements P-224 (see FIPS 186-3, section D.2.2)
-func P224() Curve {
-	initonce.Do(initAll)
-	return p224
-}
-
-func (curve p224Curve) Params() *CurveParams {
-	return curve.CurveParams
-}
-
-func (curve p224Curve) IsOnCurve(bigX, bigY *big.Int) bool {
-	var x, y p224FieldElement
-	p224FromBig(&x, bigX)
-	p224FromBig(&y, bigY)
-
-	// y² = x³ - 3x + b
-	var tmp p224LargeFieldElement
-	var x3 p224FieldElement
-	p224Square(&x3, &x, &tmp)
-	p224Mul(&x3, &x3, &x, &tmp)
-
-	for i := 0; i < 8; i++ {
-		x[i] *= 3
-	}
-	p224Sub(&x3, &x3, &x)
-	p224Reduce(&x3)
-	p224Add(&x3, &x3, &curve.b)
-	p224Contract(&x3, &x3)
-
-	p224Square(&y, &y, &tmp)
-	p224Contract(&y, &y)
-
-	for i := 0; i < 8; i++ {
-		if y[i] != x3[i] {
-			return false
-		}
-	}
-	return true
-}
-
-func (p224Curve) Add(bigX1, bigY1, bigX2, bigY2 *big.Int) (x, y *big.Int) {
-	var x1, y1, z1, x2, y2, z2, x3, y3, z3 p224FieldElement
-
-	p224FromBig(&x1, bigX1)
-	p224FromBig(&y1, bigY1)
-	if bigX1.Sign() != 0 || bigY1.Sign() != 0 {
-		z1[0] = 1
-	}
-	p224FromBig(&x2, bigX2)
-	p224FromBig(&y2, bigY2)
-	if bigX2.Sign() != 0 || bigY2.Sign() != 0 {
-		z2[0] = 1
-	}
-
-	p224AddJacobian(&x3, &y3, &z3, &x1, &y1, &z1, &x2, &y2, &z2)
-	return p224ToAffine(&x3, &y3, &z3)
-}
-
-func (p224Curve) Double(bigX1, bigY1 *big.Int) (x, y *big.Int) {
-	var x1, y1, z1, x2, y2, z2 p224FieldElement
-
-	p224FromBig(&x1, bigX1)
-	p224FromBig(&y1, bigY1)
-	z1[0] = 1
-
-	p224DoubleJacobian(&x2, &y2, &z2, &x1, &y1, &z1)
-	return p224ToAffine(&x2, &y2, &z2)
-}
-
-func (p224Curve) ScalarMult(bigX1, bigY1 *big.Int, scalar []byte) (x, y *big.Int) {
-	var x1, y1, z1, x2, y2, z2 p224FieldElement
-
-	p224FromBig(&x1, bigX1)
-	p224FromBig(&y1, bigY1)
-	z1[0] = 1
-
-	p224ScalarMult(&x2, &y2, &z2, &x1, &y1, &z1, scalar)
-	return p224ToAffine(&x2, &y2, &z2)
-}
-
-func (curve p224Curve) ScalarBaseMult(scalar []byte) (x, y *big.Int) {
-	var z1, x2, y2, z2 p224FieldElement
-
-	z1[0] = 1
-	p224ScalarMult(&x2, &y2, &z2, &curve.gx, &curve.gy, &z1, scalar)
-	return p224ToAffine(&x2, &y2, &z2)
-}
-
-// Field element functions.
-//
-// The field that we're dealing with is ℤ/pℤ where p = 2**224 - 2**96 + 1.
-//
-// Field elements are represented by a FieldElement, which is a typedef to an
-// array of 8 uint32's. The value of a FieldElement, a, is:
-//   a[0] + 2**28·a[1] + 2**56·a[1] + ... + 2**196·a[7]
-//
-// Using 28-bit limbs means that there's only 4 bits of headroom, which is less
-// than we would really like. But it has the useful feature that we hit 2**224
-// exactly, making the reflections during a reduce much nicer.
-type p224FieldElement [8]uint32
-
-// p224P is the order of the field, represented as a p224FieldElement.
-var p224P = [8]uint32{1, 0, 0, 0xffff000, 0xfffffff, 0xfffffff, 0xfffffff, 0xfffffff}
-
-// p224IsZero returns 1 if a == 0 mod p and 0 otherwise.
-//
-// a[i] < 2**29
-func p224IsZero(a *p224FieldElement) uint32 {
-	// Since a p224FieldElement contains 224 bits there are two possible
-	// representations of 0: 0 and p.
-	var minimal p224FieldElement
-	p224Contract(&minimal, a)
-
-	var isZero, isP uint32
-	for i, v := range minimal {
-		isZero |= v
-		isP |= v - p224P[i]
-	}
-
-	// If either isZero or isP is 0, then we should return 1.
-	isZero |= isZero >> 16
-	isZero |= isZero >> 8
-	isZero |= isZero >> 4
-	isZero |= isZero >> 2
-	isZero |= isZero >> 1
-
-	isP |= isP >> 16
-	isP |= isP >> 8
-	isP |= isP >> 4
-	isP |= isP >> 2
-	isP |= isP >> 1
-
-	// For isZero and isP, the LSB is 0 iff all the bits are zero.
-	result := isZero & isP
-	result = (^result) & 1
-
-	return result
-}
-
-// p224Add computes *out = a+b
-//
-// a[i] + b[i] < 2**32
-func p224Add(out, a, b *p224FieldElement) {
-	for i := 0; i < 8; i++ {
-		out[i] = a[i] + b[i]
-	}
-}
-
-const two31p3 = 1<<31 + 1<<3
-const two31m3 = 1<<31 - 1<<3
-const two31m15m3 = 1<<31 - 1<<15 - 1<<3
-
-// p224ZeroModP31 is 0 mod p where bit 31 is set in all limbs so that we can
-// subtract smaller amounts without underflow. See the section "Subtraction" in
-// [1] for reasoning.
-var p224ZeroModP31 = []uint32{two31p3, two31m3, two31m3, two31m15m3, two31m3, two31m3, two31m3, two31m3}
-
-// p224Sub computes *out = a-b
-//
-// a[i], b[i] < 2**30
-// out[i] < 2**32
-func p224Sub(out, a, b *p224FieldElement) {
-	for i := 0; i < 8; i++ {
-		out[i] = a[i] + p224ZeroModP31[i] - b[i]
-	}
-}
-
-// LargeFieldElement also represents an element of the field. The limbs are
-// still spaced 28-bits apart and in little-endian order. So the limbs are at
-// 0, 28, 56, ..., 392 bits, each 64-bits wide.
-type p224LargeFieldElement [15]uint64
-
-const two63p35 = 1<<63 + 1<<35
-const two63m35 = 1<<63 - 1<<35
-const two63m35m19 = 1<<63 - 1<<35 - 1<<19
-
-// p224ZeroModP63 is 0 mod p where bit 63 is set in all limbs. See the section
-// "Subtraction" in [1] for why.
-var p224ZeroModP63 = [8]uint64{two63p35, two63m35, two63m35, two63m35, two63m35m19, two63m35, two63m35, two63m35}
-
-const bottom12Bits = 0xfff
-const bottom28Bits = 0xfffffff
-
-// p224Mul computes *out = a*b
-//
-// a[i] < 2**29, b[i] < 2**30 (or vice versa)
-// out[i] < 2**29
-func p224Mul(out, a, b *p224FieldElement, tmp *p224LargeFieldElement) {
-	for i := 0; i < 15; i++ {
-		tmp[i] = 0
-	}
-
-	for i := 0; i < 8; i++ {
-		for j := 0; j < 8; j++ {
-			tmp[i+j] += uint64(a[i]) * uint64(b[j])
-		}
-	}
-
-	p224ReduceLarge(out, tmp)
-}
-
-// Square computes *out = a*a
-//
-// a[i] < 2**29
-// out[i] < 2**29
-func p224Square(out, a *p224FieldElement, tmp *p224LargeFieldElement) {
-	for i := 0; i < 15; i++ {
-		tmp[i] = 0
-	}
-
-	for i := 0; i < 8; i++ {
-		for j := 0; j <= i; j++ {
-			r := uint64(a[i]) * uint64(a[j])
-			if i == j {
-				tmp[i+j] += r
-			} else {
-				tmp[i+j] += r << 1
-			}
-		}
-	}
-
-	p224ReduceLarge(out, tmp)
-}
-
-// ReduceLarge converts a p224LargeFieldElement to a p224FieldElement.
-//
-// in[i] < 2**62
-func p224ReduceLarge(out *p224FieldElement, in *p224LargeFieldElement) {
-	for i := 0; i < 8; i++ {
-		in[i] += p224ZeroModP63[i]
-	}
-
-	// Eliminate the coefficients at 2**224 and greater.
-	for i := 14; i >= 8; i-- {
-		in[i-8] -= in[i]
-		in[i-5] += (in[i] & 0xffff) << 12
-		in[i-4] += in[i] >> 16
-	}
-	in[8] = 0
-	// in[0..8] < 2**64
-
-	// As the values become small enough, we start to store them in |out|
-	// and use 32-bit operations.
-	for i := 1; i < 8; i++ {
-		in[i+1] += in[i] >> 28
-		out[i] = uint32(in[i] & bottom28Bits)
-	}
-	in[0] -= in[8]
-	out[3] += uint32(in[8]&0xffff) << 12
-	out[4] += uint32(in[8] >> 16)
-	// in[0] < 2**64
-	// out[3] < 2**29
-	// out[4] < 2**29
-	// out[1,2,5..7] < 2**28
-
-	out[0] = uint32(in[0] & bottom28Bits)
-	out[1] += uint32((in[0] >> 28) & bottom28Bits)
-	out[2] += uint32(in[0] >> 56)
-	// out[0] < 2**28
-	// out[1..4] < 2**29
-	// out[5..7] < 2**28
-}
-
-// Reduce reduces the coefficients of a to smaller bounds.
-//
-// On entry: a[i] < 2**31 + 2**30
-// On exit: a[i] < 2**29
-func p224Reduce(a *p224FieldElement) {
-	for i := 0; i < 7; i++ {
-		a[i+1] += a[i] >> 28
-		a[i] &= bottom28Bits
-	}
-	top := a[7] >> 28
-	a[7] &= bottom28Bits
-
-	// top < 2**4
-	mask := top
-	mask |= mask >> 2
-	mask |= mask >> 1
-	mask <<= 31
-	mask = uint32(int32(mask) >> 31)
-	// Mask is all ones if top != 0, all zero otherwise
-
-	a[0] -= top
-	a[3] += top << 12
-
-	// We may have just made a[0] negative but, if we did, then we must
-	// have added something to a[3], this it's > 2**12. Therefore we can
-	// carry down to a[0].
-	a[3] -= 1 & mask
-	a[2] += mask & (1<<28 - 1)
-	a[1] += mask & (1<<28 - 1)
-	a[0] += mask & (1 << 28)
-}
-
-// p224Invert calculates *out = in**-1 by computing in**(2**224 - 2**96 - 1),
-// i.e. Fermat's little theorem.
-func p224Invert(out, in *p224FieldElement) {
-	var f1, f2, f3, f4 p224FieldElement
-	var c p224LargeFieldElement
-
-	p224Square(&f1, in, &c)    // 2
-	p224Mul(&f1, &f1, in, &c)  // 2**2 - 1
-	p224Square(&f1, &f1, &c)   // 2**3 - 2
-	p224Mul(&f1, &f1, in, &c)  // 2**3 - 1
-	p224Square(&f2, &f1, &c)   // 2**4 - 2
-	p224Square(&f2, &f2, &c)   // 2**5 - 4
-	p224Square(&f2, &f2, &c)   // 2**6 - 8
-	p224Mul(&f1, &f1, &f2, &c) // 2**6 - 1
-	p224Square(&f2, &f1, &c)   // 2**7 - 2
-	for i := 0; i < 5; i++ {   // 2**12 - 2**6
-		p224Square(&f2, &f2, &c)
-	}
-	p224Mul(&f2, &f2, &f1, &c) // 2**12 - 1
-	p224Square(&f3, &f2, &c)   // 2**13 - 2
-	for i := 0; i < 11; i++ {  // 2**24 - 2**12
-		p224Square(&f3, &f3, &c)
-	}
-	p224Mul(&f2, &f3, &f2, &c) // 2**24 - 1
-	p224Square(&f3, &f2, &c)   // 2**25 - 2
-	for i := 0; i < 23; i++ {  // 2**48 - 2**24
-		p224Square(&f3, &f3, &c)
-	}
-	p224Mul(&f3, &f3, &f2, &c) // 2**48 - 1
-	p224Square(&f4, &f3, &c)   // 2**49 - 2
-	for i := 0; i < 47; i++ {  // 2**96 - 2**48
-		p224Square(&f4, &f4, &c)
-	}
-	p224Mul(&f3, &f3, &f4, &c) // 2**96 - 1
-	p224Square(&f4, &f3, &c)   // 2**97 - 2
-	for i := 0; i < 23; i++ {  // 2**120 - 2**24
-		p224Square(&f4, &f4, &c)
-	}
-	p224Mul(&f2, &f4, &f2, &c) // 2**120 - 1
-	for i := 0; i < 6; i++ {   // 2**126 - 2**6
-		p224Square(&f2, &f2, &c)
-	}
-	p224Mul(&f1, &f1, &f2, &c) // 2**126 - 1
-	p224Square(&f1, &f1, &c)   // 2**127 - 2
-	p224Mul(&f1, &f1, in, &c)  // 2**127 - 1
-	for i := 0; i < 97; i++ {  // 2**224 - 2**97
-		p224Square(&f1, &f1, &c)
-	}
-	p224Mul(out, &f1, &f3, &c) // 2**224 - 2**96 - 1
-}
-
-// p224Contract converts a FieldElement to its unique, minimal form.
-//
-// On entry, in[i] < 2**29
-// On exit, in[i] < 2**28
-func p224Contract(out, in *p224FieldElement) {
-	copy(out[:], in[:])
-
-	for i := 0; i < 7; i++ {
-		out[i+1] += out[i] >> 28
-		out[i] &= bottom28Bits
-	}
-	top := out[7] >> 28
-	out[7] &= bottom28Bits
-
-	out[0] -= top
-	out[3] += top << 12
-
-	// We may just have made out[i] negative. So we carry down. If we made
-	// out[0] negative then we know that out[3] is sufficiently positive
-	// because we just added to it.
-	for i := 0; i < 3; i++ {
-		mask := uint32(int32(out[i]) >> 31)
-		out[i] += (1 << 28) & mask
-		out[i+1] -= 1 & mask
-	}
-
-	// We might have pushed out[3] over 2**28 so we perform another, partial,
-	// carry chain.
-	for i := 3; i < 7; i++ {
-		out[i+1] += out[i] >> 28
-		out[i] &= bottom28Bits
-	}
-	top = out[7] >> 28
-	out[7] &= bottom28Bits
-
-	// Eliminate top while maintaining the same value mod p.
-	out[0] -= top
-	out[3] += top << 12
-
-	// There are two cases to consider for out[3]:
-	//   1) The first time that we eliminated top, we didn't push out[3] over
-	//      2**28. In this case, the partial carry chain didn't change any values
-	//      and top is zero.
-	//   2) We did push out[3] over 2**28 the first time that we eliminated top.
-	//      The first value of top was in [0..16), therefore, prior to eliminating
-	//      the first top, 0xfff1000 <= out[3] <= 0xfffffff. Therefore, after
-	//      overflowing and being reduced by the second carry chain, out[3] <=
-	//      0xf000. Thus it cannot have overflowed when we eliminated top for the
-	//      second time.
-
-	// Again, we may just have made out[0] negative, so do the same carry down.
-	// As before, if we made out[0] negative then we know that out[3] is
-	// sufficiently positive.
-	for i := 0; i < 3; i++ {
-		mask := uint32(int32(out[i]) >> 31)
-		out[i] += (1 << 28) & mask
-		out[i+1] -= 1 & mask
-	}
-
-	// Now we see if the value is >= p and, if so, subtract p.
-
-	// First we build a mask from the top four limbs, which must all be
-	// equal to bottom28Bits if the whole value is >= p. If top4AllOnes
-	// ends up with any zero bits in the bottom 28 bits, then this wasn't
-	// true.
-	top4AllOnes := uint32(0xffffffff)
-	for i := 4; i < 8; i++ {
-		top4AllOnes &= out[i]
-	}
-	top4AllOnes |= 0xf0000000
-	// Now we replicate any zero bits to all the bits in top4AllOnes.
-	top4AllOnes &= top4AllOnes >> 16
-	top4AllOnes &= top4AllOnes >> 8
-	top4AllOnes &= top4AllOnes >> 4
-	top4AllOnes &= top4AllOnes >> 2
-	top4AllOnes &= top4AllOnes >> 1
-	top4AllOnes = uint32(int32(top4AllOnes<<31) >> 31)
-
-	// Now we test whether the bottom three limbs are non-zero.
-	bottom3NonZero := out[0] | out[1] | out[2]
-	bottom3NonZero |= bottom3NonZero >> 16
-	bottom3NonZero |= bottom3NonZero >> 8
-	bottom3NonZero |= bottom3NonZero >> 4
-	bottom3NonZero |= bottom3NonZero >> 2
-	bottom3NonZero |= bottom3NonZero >> 1
-	bottom3NonZero = uint32(int32(bottom3NonZero<<31) >> 31)
-
-	// Everything depends on the value of out[3].
-	//    If it's > 0xffff000 and top4AllOnes != 0 then the whole value is >= p
-	//    If it's = 0xffff000 and top4AllOnes != 0 and bottom3NonZero != 0,
-	//      then the whole value is >= p
-	//    If it's < 0xffff000, then the whole value is < p
-	n := out[3] - 0xffff000
-	out3Equal := n
-	out3Equal |= out3Equal >> 16
-	out3Equal |= out3Equal >> 8
-	out3Equal |= out3Equal >> 4
-	out3Equal |= out3Equal >> 2
-	out3Equal |= out3Equal >> 1
-	out3Equal = ^uint32(int32(out3Equal<<31) >> 31)
-
-	// If out[3] > 0xffff000 then n's MSB will be zero.
-	out3GT := ^uint32(int32(n) >> 31)
-
-	mask := top4AllOnes & ((out3Equal & bottom3NonZero) | out3GT)
-	out[0] -= 1 & mask
-	out[3] -= 0xffff000 & mask
-	out[4] -= 0xfffffff & mask
-	out[5] -= 0xfffffff & mask
-	out[6] -= 0xfffffff & mask
-	out[7] -= 0xfffffff & mask
-}
-
-// Group element functions.
-//
-// These functions deal with group elements. The group is an elliptic curve
-// group with a = -3 defined in FIPS 186-3, section D.2.2.
-
-// p224AddJacobian computes *out = a+b where a != b.
-func p224AddJacobian(x3, y3, z3, x1, y1, z1, x2, y2, z2 *p224FieldElement) {
-	// See http://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-3.html#addition-p224Add-2007-bl
-	var z1z1, z2z2, u1, u2, s1, s2, h, i, j, r, v p224FieldElement
-	var c p224LargeFieldElement
-
-	z1IsZero := p224IsZero(z1)
-	z2IsZero := p224IsZero(z2)
-
-	// Z1Z1 = Z1²
-	p224Square(&z1z1, z1, &c)
-	// Z2Z2 = Z2²
-	p224Square(&z2z2, z2, &c)
-	// U1 = X1*Z2Z2
-	p224Mul(&u1, x1, &z2z2, &c)
-	// U2 = X2*Z1Z1
-	p224Mul(&u2, x2, &z1z1, &c)
-	// S1 = Y1*Z2*Z2Z2
-	p224Mul(&s1, z2, &z2z2, &c)
-	p224Mul(&s1, y1, &s1, &c)
-	// S2 = Y2*Z1*Z1Z1
-	p224Mul(&s2, z1, &z1z1, &c)
-	p224Mul(&s2, y2, &s2, &c)
-	// H = U2-U1
-	p224Sub(&h, &u2, &u1)
-	p224Reduce(&h)
-	xEqual := p224IsZero(&h)
-	// I = (2*H)²
-	for j := 0; j < 8; j++ {
-		i[j] = h[j] << 1
-	}
-	p224Reduce(&i)
-	p224Square(&i, &i, &c)
-	// J = H*I
-	p224Mul(&j, &h, &i, &c)
-	// r = 2*(S2-S1)
-	p224Sub(&r, &s2, &s1)
-	p224Reduce(&r)
-	yEqual := p224IsZero(&r)
-	if xEqual == 1 && yEqual == 1 && z1IsZero == 0 && z2IsZero == 0 {
-		p224DoubleJacobian(x3, y3, z3, x1, y1, z1)
-		return
-	}
-	for i := 0; i < 8; i++ {
-		r[i] <<= 1
-	}
-	p224Reduce(&r)
-	// V = U1*I
-	p224Mul(&v, &u1, &i, &c)
-	// Z3 = ((Z1+Z2)²-Z1Z1-Z2Z2)*H
-	p224Add(&z1z1, &z1z1, &z2z2)
-	p224Add(&z2z2, z1, z2)
-	p224Reduce(&z2z2)
-	p224Square(&z2z2, &z2z2, &c)
-	p224Sub(z3, &z2z2, &z1z1)
-	p224Reduce(z3)
-	p224Mul(z3, z3, &h, &c)
-	// X3 = r²-J-2*V
-	for i := 0; i < 8; i++ {
-		z1z1[i] = v[i] << 1
-	}
-	p224Add(&z1z1, &j, &z1z1)
-	p224Reduce(&z1z1)
-	p224Square(x3, &r, &c)
-	p224Sub(x3, x3, &z1z1)
-	p224Reduce(x3)
-	// Y3 = r*(V-X3)-2*S1*J
-	for i := 0; i < 8; i++ {
-		s1[i] <<= 1
-	}
-	p224Mul(&s1, &s1, &j, &c)
-	p224Sub(&z1z1, &v, x3)
-	p224Reduce(&z1z1)
-	p224Mul(&z1z1, &z1z1, &r, &c)
-	p224Sub(y3, &z1z1, &s1)
-	p224Reduce(y3)
-
-	p224CopyConditional(x3, x2, z1IsZero)
-	p224CopyConditional(x3, x1, z2IsZero)
-	p224CopyConditional(y3, y2, z1IsZero)
-	p224CopyConditional(y3, y1, z2IsZero)
-	p224CopyConditional(z3, z2, z1IsZero)
-	p224CopyConditional(z3, z1, z2IsZero)
-}
-
-// p224DoubleJacobian computes *out = a+a.
-func p224DoubleJacobian(x3, y3, z3, x1, y1, z1 *p224FieldElement) {
-	var delta, gamma, beta, alpha, t p224FieldElement
-	var c p224LargeFieldElement
-
-	p224Square(&delta, z1, &c)
-	p224Square(&gamma, y1, &c)
-	p224Mul(&beta, x1, &gamma, &c)
-
-	// alpha = 3*(X1-delta)*(X1+delta)
-	p224Add(&t, x1, &delta)
-	for i := 0; i < 8; i++ {
-		t[i] += t[i] << 1
-	}
-	p224Reduce(&t)
-	p224Sub(&alpha, x1, &delta)
-	p224Reduce(&alpha)
-	p224Mul(&alpha, &alpha, &t, &c)
-
-	// Z3 = (Y1+Z1)²-gamma-delta
-	p224Add(z3, y1, z1)
-	p224Reduce(z3)
-	p224Square(z3, z3, &c)
-	p224Sub(z3, z3, &gamma)
-	p224Reduce(z3)
-	p224Sub(z3, z3, &delta)
-	p224Reduce(z3)
-
-	// X3 = alpha²-8*beta
-	for i := 0; i < 8; i++ {
-		delta[i] = beta[i] << 3
-	}
-	p224Reduce(&delta)
-	p224Square(x3, &alpha, &c)
-	p224Sub(x3, x3, &delta)
-	p224Reduce(x3)
-
-	// Y3 = alpha*(4*beta-X3)-8*gamma²
-	for i := 0; i < 8; i++ {
-		beta[i] <<= 2
-	}
-	p224Sub(&beta, &beta, x3)
-	p224Reduce(&beta)
-	p224Square(&gamma, &gamma, &c)
-	for i := 0; i < 8; i++ {
-		gamma[i] <<= 3
-	}
-	p224Reduce(&gamma)
-	p224Mul(y3, &alpha, &beta, &c)
-	p224Sub(y3, y3, &gamma)
-	p224Reduce(y3)
-}
-
-// p224CopyConditional sets *out = *in iff the least-significant-bit of control
-// is true, and it runs in constant time.
-func p224CopyConditional(out, in *p224FieldElement, control uint32) {
-	control <<= 31
-	control = uint32(int32(control) >> 31)
-
-	for i := 0; i < 8; i++ {
-		out[i] ^= (out[i] ^ in[i]) & control
-	}
-}
-
-func p224ScalarMult(outX, outY, outZ, inX, inY, inZ *p224FieldElement, scalar []byte) {
-	var xx, yy, zz p224FieldElement
-	for i := 0; i < 8; i++ {
-		outX[i] = 0
-		outY[i] = 0
-		outZ[i] = 0
-	}
-
-	for _, byte := range scalar {
-		for bitNum := uint(0); bitNum < 8; bitNum++ {
-			p224DoubleJacobian(outX, outY, outZ, outX, outY, outZ)
-			bit := uint32((byte >> (7 - bitNum)) & 1)
-			p224AddJacobian(&xx, &yy, &zz, inX, inY, inZ, outX, outY, outZ)
-			p224CopyConditional(outX, &xx, bit)
-			p224CopyConditional(outY, &yy, bit)
-			p224CopyConditional(outZ, &zz, bit)
-		}
-	}
-}
-
-// p224ToAffine converts from Jacobian to affine form.
-func p224ToAffine(x, y, z *p224FieldElement) (*big.Int, *big.Int) {
-	var zinv, zinvsq, outx, outy p224FieldElement
-	var tmp p224LargeFieldElement
-
-	if isPointAtInfinity := p224IsZero(z); isPointAtInfinity == 1 {
-		return new(big.Int), new(big.Int)
-	}
-
-	p224Invert(&zinv, z)
-	p224Square(&zinvsq, &zinv, &tmp)
-	p224Mul(x, x, &zinvsq, &tmp)
-	p224Mul(&zinvsq, &zinvsq, &zinv, &tmp)
-	p224Mul(y, y, &zinvsq, &tmp)
-
-	p224Contract(&outx, x)
-	p224Contract(&outy, y)
-	return p224ToBig(&outx), p224ToBig(&outy)
-}
-
-// get28BitsFromEnd returns the least-significant 28 bits from buf>>shift,
-// where buf is interpreted as a big-endian number.
-func get28BitsFromEnd(buf []byte, shift uint) (uint32, []byte) {
-	var ret uint32
-
-	for i := uint(0); i < 4; i++ {
-		var b byte
-		if l := len(buf); l > 0 {
-			b = buf[l-1]
-			// We don't remove the byte if we're about to return and we're not
-			// reading all of it.
-			if i != 3 || shift == 4 {
-				buf = buf[:l-1]
-			}
-		}
-		ret |= uint32(b) << (8 * i) >> shift
-	}
-	ret &= bottom28Bits
-	return ret, buf
-}
-
-// p224FromBig sets *out = *in.
-func p224FromBig(out *p224FieldElement, in *big.Int) {
-	bytes := in.Bytes()
-	out[0], bytes = get28BitsFromEnd(bytes, 0)
-	out[1], bytes = get28BitsFromEnd(bytes, 4)
-	out[2], bytes = get28BitsFromEnd(bytes, 0)
-	out[3], bytes = get28BitsFromEnd(bytes, 4)
-	out[4], bytes = get28BitsFromEnd(bytes, 0)
-	out[5], bytes = get28BitsFromEnd(bytes, 4)
-	out[6], bytes = get28BitsFromEnd(bytes, 0)
-	out[7], bytes = get28BitsFromEnd(bytes, 4)
-}
-
-// p224ToBig returns in as a big.Int.
-func p224ToBig(in *p224FieldElement) *big.Int {
-	var buf [28]byte
-	buf[27] = byte(in[0])
-	buf[26] = byte(in[0] >> 8)
-	buf[25] = byte(in[0] >> 16)
-	buf[24] = byte(((in[0] >> 24) & 0x0f) | (in[1]<<4)&0xf0)
-
-	buf[23] = byte(in[1] >> 4)
-	buf[22] = byte(in[1] >> 12)
-	buf[21] = byte(in[1] >> 20)
-
-	buf[20] = byte(in[2])
-	buf[19] = byte(in[2] >> 8)
-	buf[18] = byte(in[2] >> 16)
-	buf[17] = byte(((in[2] >> 24) & 0x0f) | (in[3]<<4)&0xf0)
-
-	buf[16] = byte(in[3] >> 4)
-	buf[15] = byte(in[3] >> 12)
-	buf[14] = byte(in[3] >> 20)
-
-	buf[13] = byte(in[4])
-	buf[12] = byte(in[4] >> 8)
-	buf[11] = byte(in[4] >> 16)
-	buf[10] = byte(((in[4] >> 24) & 0x0f) | (in[5]<<4)&0xf0)
-
-	buf[9] = byte(in[5] >> 4)
-	buf[8] = byte(in[5] >> 12)
-	buf[7] = byte(in[5] >> 20)
-
-	buf[6] = byte(in[6])
-	buf[5] = byte(in[6] >> 8)
-	buf[4] = byte(in[6] >> 16)
-	buf[3] = byte(((in[6] >> 24) & 0x0f) | (in[7]<<4)&0xf0)
-
-	buf[2] = byte(in[7] >> 4)
-	buf[1] = byte(in[7] >> 12)
-	buf[0] = byte(in[7] >> 20)
-
-	return new(big.Int).SetBytes(buf[:])
-}
diff --git a/src/pkg/crypto/elliptic/p224_test.go b/src/pkg/crypto/elliptic/p224_test.go
deleted file mode 100644
index 4b26d1610..000000000
--- a/src/pkg/crypto/elliptic/p224_test.go
+++ /dev/null
@@ -1,47 +0,0 @@
-// 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 elliptic
-
-import (
-	"math/big"
-	"testing"
-)
-
-var toFromBigTests = []string{
-	"0",
-	"1",
-	"23",
-	"b70e0cb46bb4bf7f321390b94a03c1d356c01122343280d6105c1d21",
-	"706a46d476dcb76798e6046d89474788d164c18032d268fd10704fa6",
-}
-
-func p224AlternativeToBig(in *p224FieldElement) *big.Int {
-	ret := new(big.Int)
-	tmp := new(big.Int)
-
-	for i := uint(0); i < 8; i++ {
-		tmp.SetInt64(int64(in[i]))
-		tmp.Lsh(tmp, 28*i)
-		ret.Add(ret, tmp)
-	}
-	ret.Mod(ret, p224.P)
-	return ret
-}
-
-func TestToFromBig(t *testing.T) {
-	for i, test := range toFromBigTests {
-		n, _ := new(big.Int).SetString(test, 16)
-		var x p224FieldElement
-		p224FromBig(&x, n)
-		m := p224ToBig(&x)
-		if n.Cmp(m) != 0 {
-			t.Errorf("#%d: %x != %x", i, n, m)
-		}
-		q := p224AlternativeToBig(&x)
-		if n.Cmp(q) != 0 {
-			t.Errorf("#%d: %x != %x (alternative)", i, n, m)
-		}
-	}
-}
diff --git a/src/pkg/crypto/elliptic/p256.go b/src/pkg/crypto/elliptic/p256.go
deleted file mode 100644
index 82be51e62..000000000
--- a/src/pkg/crypto/elliptic/p256.go
+++ /dev/null
@@ -1,1186 +0,0 @@
-// Copyright 2013 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 elliptic
-
-// This file contains a constant-time, 32-bit implementation of P256.
-
-import (
-	"math/big"
-)
-
-type p256Curve struct {
-	*CurveParams
-}
-
-var (
-	p256 p256Curve
-	// RInverse contains 1/R mod p - the inverse of the Montgomery constant
-	// (2**257).
-	p256RInverse *big.Int
-)
-
-func initP256() {
-	// See FIPS 186-3, section D.2.3
-	p256.CurveParams = new(CurveParams)
-	p256.P, _ = new(big.Int).SetString("115792089210356248762697446949407573530086143415290314195533631308867097853951", 10)
-	p256.N, _ = new(big.Int).SetString("115792089210356248762697446949407573529996955224135760342422259061068512044369", 10)
-	p256.B, _ = new(big.Int).SetString("5ac635d8aa3a93e7b3ebbd55769886bc651d06b0cc53b0f63bce3c3e27d2604b", 16)
-	p256.Gx, _ = new(big.Int).SetString("6b17d1f2e12c4247f8bce6e563a440f277037d812deb33a0f4a13945d898c296", 16)
-	p256.Gy, _ = new(big.Int).SetString("4fe342e2fe1a7f9b8ee7eb4a7c0f9e162bce33576b315ececbb6406837bf51f5", 16)
-	p256.BitSize = 256
-
-	p256RInverse, _ = new(big.Int).SetString("7fffffff00000001fffffffe8000000100000000ffffffff0000000180000000", 16)
-}
-
-func (curve p256Curve) Params() *CurveParams {
-	return curve.CurveParams
-}
-
-// p256GetScalar endian-swaps the big-endian scalar value from in and writes it
-// to out. If the scalar is equal or greater than the order of the group, it's
-// reduced modulo that order.
-func p256GetScalar(out *[32]byte, in []byte) {
-	n := new(big.Int).SetBytes(in)
-	var scalarBytes []byte
-
-	if n.Cmp(p256.N) >= 0 {
-		n.Mod(n, p256.N)
-		scalarBytes = n.Bytes()
-	} else {
-		scalarBytes = in
-	}
-
-	for i, v := range scalarBytes {
-		out[len(scalarBytes)-(1+i)] = v
-	}
-}
-
-func (p256Curve) ScalarBaseMult(scalar []byte) (x, y *big.Int) {
-	var scalarReversed [32]byte
-	p256GetScalar(&scalarReversed, scalar)
-
-	var x1, y1, z1 [p256Limbs]uint32
-	p256ScalarBaseMult(&x1, &y1, &z1, &scalarReversed)
-	return p256ToAffine(&x1, &y1, &z1)
-}
-
-func (p256Curve) ScalarMult(bigX, bigY *big.Int, scalar []byte) (x, y *big.Int) {
-	var scalarReversed [32]byte
-	p256GetScalar(&scalarReversed, scalar)
-
-	var px, py, x1, y1, z1 [p256Limbs]uint32
-	p256FromBig(&px, bigX)
-	p256FromBig(&py, bigY)
-	p256ScalarMult(&x1, &y1, &z1, &px, &py, &scalarReversed)
-	return p256ToAffine(&x1, &y1, &z1)
-}
-
-// Field elements are represented as nine, unsigned 32-bit words.
-//
-// The value of an field element is:
-//   x[0] + (x[1] * 2**29) + (x[2] * 2**57) + ... + (x[8] * 2**228)
-//
-// That is, each limb is alternately 29 or 28-bits wide in little-endian
-// order.
-//
-// This means that a field element hits 2**257, rather than 2**256 as we would
-// like. A 28, 29, ... pattern would cause us to hit 2**256, but that causes
-// problems when multiplying as terms end up one bit short of a limb which
-// would require much bit-shifting to correct.
-//
-// Finally, the values stored in a field element are in Montgomery form. So the
-// value |y| is stored as (y*R) mod p, where p is the P-256 prime and R is
-// 2**257.
-
-const (
-	p256Limbs    = 9
-	bottom29Bits = 0x1fffffff
-)
-
-var (
-	// p256One is the number 1 as a field element.
-	p256One  = [p256Limbs]uint32{2, 0, 0, 0xffff800, 0x1fffffff, 0xfffffff, 0x1fbfffff, 0x1ffffff, 0}
-	p256Zero = [p256Limbs]uint32{0, 0, 0, 0, 0, 0, 0, 0, 0}
-	// p256P is the prime modulus as a field element.
-	p256P = [p256Limbs]uint32{0x1fffffff, 0xfffffff, 0x1fffffff, 0x3ff, 0, 0, 0x200000, 0xf000000, 0xfffffff}
-	// p2562P is the twice prime modulus as a field element.
-	p2562P = [p256Limbs]uint32{0x1ffffffe, 0xfffffff, 0x1fffffff, 0x7ff, 0, 0, 0x400000, 0xe000000, 0x1fffffff}
-)
-
-// p256Precomputed contains precomputed values to aid the calculation of scalar
-// multiples of the base point, G. It's actually two, equal length, tables
-// concatenated.
-//
-// The first table contains (x,y) field element pairs for 16 multiples of the
-// base point, G.
-//
-//   Index  |  Index (binary) | Value
-//       0  |           0000  | 0G (all zeros, omitted)
-//       1  |           0001  | G
-//       2  |           0010  | 2**64G
-//       3  |           0011  | 2**64G + G
-//       4  |           0100  | 2**128G
-//       5  |           0101  | 2**128G + G
-//       6  |           0110  | 2**128G + 2**64G
-//       7  |           0111  | 2**128G + 2**64G + G
-//       8  |           1000  | 2**192G
-//       9  |           1001  | 2**192G + G
-//      10  |           1010  | 2**192G + 2**64G
-//      11  |           1011  | 2**192G + 2**64G + G
-//      12  |           1100  | 2**192G + 2**128G
-//      13  |           1101  | 2**192G + 2**128G + G
-//      14  |           1110  | 2**192G + 2**128G + 2**64G
-//      15  |           1111  | 2**192G + 2**128G + 2**64G + G
-//
-// The second table follows the same style, but the terms are 2**32G,
-// 2**96G, 2**160G, 2**224G.
-//
-// This is ~2KB of data.
-var p256Precomputed = [p256Limbs * 2 * 15 * 2]uint32{
-	0x11522878, 0xe730d41, 0xdb60179, 0x4afe2ff, 0x12883add, 0xcaddd88, 0x119e7edc, 0xd4a6eab, 0x3120bee,
-	0x1d2aac15, 0xf25357c, 0x19e45cdd, 0x5c721d0, 0x1992c5a5, 0xa237487, 0x154ba21, 0x14b10bb, 0xae3fe3,
-	0xd41a576, 0x922fc51, 0x234994f, 0x60b60d3, 0x164586ae, 0xce95f18, 0x1fe49073, 0x3fa36cc, 0x5ebcd2c,
-	0xb402f2f, 0x15c70bf, 0x1561925c, 0x5a26704, 0xda91e90, 0xcdc1c7f, 0x1ea12446, 0xe1ade1e, 0xec91f22,
-	0x26f7778, 0x566847e, 0xa0bec9e, 0x234f453, 0x1a31f21a, 0xd85e75c, 0x56c7109, 0xa267a00, 0xb57c050,
-	0x98fb57, 0xaa837cc, 0x60c0792, 0xcfa5e19, 0x61bab9e, 0x589e39b, 0xa324c5, 0x7d6dee7, 0x2976e4b,
-	0x1fc4124a, 0xa8c244b, 0x1ce86762, 0xcd61c7e, 0x1831c8e0, 0x75774e1, 0x1d96a5a9, 0x843a649, 0xc3ab0fa,
-	0x6e2e7d5, 0x7673a2a, 0x178b65e8, 0x4003e9b, 0x1a1f11c2, 0x7816ea, 0xf643e11, 0x58c43df, 0xf423fc2,
-	0x19633ffa, 0x891f2b2, 0x123c231c, 0x46add8c, 0x54700dd, 0x59e2b17, 0x172db40f, 0x83e277d, 0xb0dd609,
-	0xfd1da12, 0x35c6e52, 0x19ede20c, 0xd19e0c0, 0x97d0f40, 0xb015b19, 0x449e3f5, 0xe10c9e, 0x33ab581,
-	0x56a67ab, 0x577734d, 0x1dddc062, 0xc57b10d, 0x149b39d, 0x26a9e7b, 0xc35df9f, 0x48764cd, 0x76dbcca,
-	0xca4b366, 0xe9303ab, 0x1a7480e7, 0x57e9e81, 0x1e13eb50, 0xf466cf3, 0x6f16b20, 0x4ba3173, 0xc168c33,
-	0x15cb5439, 0x6a38e11, 0x73658bd, 0xb29564f, 0x3f6dc5b, 0x53b97e, 0x1322c4c0, 0x65dd7ff, 0x3a1e4f6,
-	0x14e614aa, 0x9246317, 0x1bc83aca, 0xad97eed, 0xd38ce4a, 0xf82b006, 0x341f077, 0xa6add89, 0x4894acd,
-	0x9f162d5, 0xf8410ef, 0x1b266a56, 0xd7f223, 0x3e0cb92, 0xe39b672, 0x6a2901a, 0x69a8556, 0x7e7c0,
-	0x9b7d8d3, 0x309a80, 0x1ad05f7f, 0xc2fb5dd, 0xcbfd41d, 0x9ceb638, 0x1051825c, 0xda0cf5b, 0x812e881,
-	0x6f35669, 0x6a56f2c, 0x1df8d184, 0x345820, 0x1477d477, 0x1645db1, 0xbe80c51, 0xc22be3e, 0xe35e65a,
-	0x1aeb7aa0, 0xc375315, 0xf67bc99, 0x7fdd7b9, 0x191fc1be, 0x61235d, 0x2c184e9, 0x1c5a839, 0x47a1e26,
-	0xb7cb456, 0x93e225d, 0x14f3c6ed, 0xccc1ac9, 0x17fe37f3, 0x4988989, 0x1a90c502, 0x2f32042, 0xa17769b,
-	0xafd8c7c, 0x8191c6e, 0x1dcdb237, 0x16200c0, 0x107b32a1, 0x66c08db, 0x10d06a02, 0x3fc93, 0x5620023,
-	0x16722b27, 0x68b5c59, 0x270fcfc, 0xfad0ecc, 0xe5de1c2, 0xeab466b, 0x2fc513c, 0x407f75c, 0xbaab133,
-	0x9705fe9, 0xb88b8e7, 0x734c993, 0x1e1ff8f, 0x19156970, 0xabd0f00, 0x10469ea7, 0x3293ac0, 0xcdc98aa,
-	0x1d843fd, 0xe14bfe8, 0x15be825f, 0x8b5212, 0xeb3fb67, 0x81cbd29, 0xbc62f16, 0x2b6fcc7, 0xf5a4e29,
-	0x13560b66, 0xc0b6ac2, 0x51ae690, 0xd41e271, 0xf3e9bd4, 0x1d70aab, 0x1029f72, 0x73e1c35, 0xee70fbc,
-	0xad81baf, 0x9ecc49a, 0x86c741e, 0xfe6be30, 0x176752e7, 0x23d416, 0x1f83de85, 0x27de188, 0x66f70b8,
-	0x181cd51f, 0x96b6e4c, 0x188f2335, 0xa5df759, 0x17a77eb6, 0xfeb0e73, 0x154ae914, 0x2f3ec51, 0x3826b59,
-	0xb91f17d, 0x1c72949, 0x1362bf0a, 0xe23fddf, 0xa5614b0, 0xf7d8f, 0x79061, 0x823d9d2, 0x8213f39,
-	0x1128ae0b, 0xd095d05, 0xb85c0c2, 0x1ecb2ef, 0x24ddc84, 0xe35e901, 0x18411a4a, 0xf5ddc3d, 0x3786689,
-	0x52260e8, 0x5ae3564, 0x542b10d, 0x8d93a45, 0x19952aa4, 0x996cc41, 0x1051a729, 0x4be3499, 0x52b23aa,
-	0x109f307e, 0x6f5b6bb, 0x1f84e1e7, 0x77a0cfa, 0x10c4df3f, 0x25a02ea, 0xb048035, 0xe31de66, 0xc6ecaa3,
-	0x28ea335, 0x2886024, 0x1372f020, 0xf55d35, 0x15e4684c, 0xf2a9e17, 0x1a4a7529, 0xcb7beb1, 0xb2a78a1,
-	0x1ab21f1f, 0x6361ccf, 0x6c9179d, 0xb135627, 0x1267b974, 0x4408bad, 0x1cbff658, 0xe3d6511, 0xc7d76f,
-	0x1cc7a69, 0xe7ee31b, 0x54fab4f, 0x2b914f, 0x1ad27a30, 0xcd3579e, 0xc50124c, 0x50daa90, 0xb13f72,
-	0xb06aa75, 0x70f5cc6, 0x1649e5aa, 0x84a5312, 0x329043c, 0x41c4011, 0x13d32411, 0xb04a838, 0xd760d2d,
-	0x1713b532, 0xbaa0c03, 0x84022ab, 0x6bcf5c1, 0x2f45379, 0x18ae070, 0x18c9e11e, 0x20bca9a, 0x66f496b,
-	0x3eef294, 0x67500d2, 0xd7f613c, 0x2dbbeb, 0xb741038, 0xe04133f, 0x1582968d, 0xbe985f7, 0x1acbc1a,
-	0x1a6a939f, 0x33e50f6, 0xd665ed4, 0xb4b7bd6, 0x1e5a3799, 0x6b33847, 0x17fa56ff, 0x65ef930, 0x21dc4a,
-	0x2b37659, 0x450fe17, 0xb357b65, 0xdf5efac, 0x15397bef, 0x9d35a7f, 0x112ac15f, 0x624e62e, 0xa90ae2f,
-	0x107eecd2, 0x1f69bbe, 0x77d6bce, 0x5741394, 0x13c684fc, 0x950c910, 0x725522b, 0xdc78583, 0x40eeabb,
-	0x1fde328a, 0xbd61d96, 0xd28c387, 0x9e77d89, 0x12550c40, 0x759cb7d, 0x367ef34, 0xae2a960, 0x91b8bdc,
-	0x93462a9, 0xf469ef, 0xb2e9aef, 0xd2ca771, 0x54e1f42, 0x7aaa49, 0x6316abb, 0x2413c8e, 0x5425bf9,
-	0x1bed3e3a, 0xf272274, 0x1f5e7326, 0x6416517, 0xea27072, 0x9cedea7, 0x6e7633, 0x7c91952, 0xd806dce,
-	0x8e2a7e1, 0xe421e1a, 0x418c9e1, 0x1dbc890, 0x1b395c36, 0xa1dc175, 0x1dc4ef73, 0x8956f34, 0xe4b5cf2,
-	0x1b0d3a18, 0x3194a36, 0x6c2641f, 0xe44124c, 0xa2f4eaa, 0xa8c25ba, 0xf927ed7, 0x627b614, 0x7371cca,
-	0xba16694, 0x417bc03, 0x7c0a7e3, 0x9c35c19, 0x1168a205, 0x8b6b00d, 0x10e3edc9, 0x9c19bf2, 0x5882229,
-	0x1b2b4162, 0xa5cef1a, 0x1543622b, 0x9bd433e, 0x364e04d, 0x7480792, 0x5c9b5b3, 0xe85ff25, 0x408ef57,
-	0x1814cfa4, 0x121b41b, 0xd248a0f, 0x3b05222, 0x39bb16a, 0xc75966d, 0xa038113, 0xa4a1769, 0x11fbc6c,
-	0x917e50e, 0xeec3da8, 0x169d6eac, 0x10c1699, 0xa416153, 0xf724912, 0x15cd60b7, 0x4acbad9, 0x5efc5fa,
-	0xf150ed7, 0x122b51, 0x1104b40a, 0xcb7f442, 0xfbb28ff, 0x6ac53ca, 0x196142cc, 0x7bf0fa9, 0x957651,
-	0x4e0f215, 0xed439f8, 0x3f46bd5, 0x5ace82f, 0x110916b6, 0x6db078, 0xffd7d57, 0xf2ecaac, 0xca86dec,
-	0x15d6b2da, 0x965ecc9, 0x1c92b4c2, 0x1f3811, 0x1cb080f5, 0x2d8b804, 0x19d1c12d, 0xf20bd46, 0x1951fa7,
-	0xa3656c3, 0x523a425, 0xfcd0692, 0xd44ddc8, 0x131f0f5b, 0xaf80e4a, 0xcd9fc74, 0x99bb618, 0x2db944c,
-	0xa673090, 0x1c210e1, 0x178c8d23, 0x1474383, 0x10b8743d, 0x985a55b, 0x2e74779, 0x576138, 0x9587927,
-	0x133130fa, 0xbe05516, 0x9f4d619, 0xbb62570, 0x99ec591, 0xd9468fe, 0x1d07782d, 0xfc72e0b, 0x701b298,
-	0x1863863b, 0x85954b8, 0x121a0c36, 0x9e7fedf, 0xf64b429, 0x9b9d71e, 0x14e2f5d8, 0xf858d3a, 0x942eea8,
-	0xda5b765, 0x6edafff, 0xa9d18cc, 0xc65e4ba, 0x1c747e86, 0xe4ea915, 0x1981d7a1, 0x8395659, 0x52ed4e2,
-	0x87d43b7, 0x37ab11b, 0x19d292ce, 0xf8d4692, 0x18c3053f, 0x8863e13, 0x4c146c0, 0x6bdf55a, 0x4e4457d,
-	0x16152289, 0xac78ec2, 0x1a59c5a2, 0x2028b97, 0x71c2d01, 0x295851f, 0x404747b, 0x878558d, 0x7d29aa4,
-	0x13d8341f, 0x8daefd7, 0x139c972d, 0x6b7ea75, 0xd4a9dde, 0xff163d8, 0x81d55d7, 0xa5bef68, 0xb7b30d8,
-	0xbe73d6f, 0xaa88141, 0xd976c81, 0x7e7a9cc, 0x18beb771, 0xd773cbd, 0x13f51951, 0x9d0c177, 0x1c49a78,
-}
-
-// Field element operations:
-
-// nonZeroToAllOnes returns:
-//   0xffffffff for 0 < x <= 2**31
-//   0 for x == 0 or x > 2**31.
-func nonZeroToAllOnes(x uint32) uint32 {
-	return ((x - 1) >> 31) - 1
-}
-
-// p256ReduceCarry adds a multiple of p in order to cancel |carry|,
-// which is a term at 2**257.
-//
-// On entry: carry < 2**3, inout[0,2,...] < 2**29, inout[1,3,...] < 2**28.
-// On exit: inout[0,2,..] < 2**30, inout[1,3,...] < 2**29.
-func p256ReduceCarry(inout *[p256Limbs]uint32, carry uint32) {
-	carry_mask := nonZeroToAllOnes(carry)
-
-	inout[0] += carry << 1
-	inout[3] += 0x10000000 & carry_mask
-	// carry < 2**3 thus (carry << 11) < 2**14 and we added 2**28 in the
-	// previous line therefore this doesn't underflow.
-	inout[3] -= carry << 11
-	inout[4] += (0x20000000 - 1) & carry_mask
-	inout[5] += (0x10000000 - 1) & carry_mask
-	inout[6] += (0x20000000 - 1) & carry_mask
-	inout[6] -= carry << 22
-	// This may underflow if carry is non-zero but, if so, we'll fix it in the
-	// next line.
-	inout[7] -= 1 & carry_mask
-	inout[7] += carry << 25
-}
-
-// p256Sum sets out = in+in2.
-//
-// On entry, in[i]+in2[i] must not overflow a 32-bit word.
-// On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29
-func p256Sum(out, in, in2 *[p256Limbs]uint32) {
-	carry := uint32(0)
-	for i := 0; ; i++ {
-		out[i] = in[i] + in2[i]
-		out[i] += carry
-		carry = out[i] >> 29
-		out[i] &= bottom29Bits
-
-		i++
-		if i == p256Limbs {
-			break
-		}
-
-		out[i] = in[i] + in2[i]
-		out[i] += carry
-		carry = out[i] >> 28
-		out[i] &= bottom28Bits
-	}
-
-	p256ReduceCarry(out, carry)
-}
-
-const (
-	two30m2    = 1<<30 - 1<<2
-	two30p13m2 = 1<<30 + 1<<13 - 1<<2
-	two31m2    = 1<<31 - 1<<2
-	two31p24m2 = 1<<31 + 1<<24 - 1<<2
-	two30m27m2 = 1<<30 - 1<<27 - 1<<2
-)
-
-// p256Zero31 is 0 mod p.
-var p256Zero31 = [p256Limbs]uint32{two31m3, two30m2, two31m2, two30p13m2, two31m2, two30m2, two31p24m2, two30m27m2, two31m2}
-
-// p256Diff sets out = in-in2.
-//
-// On entry: in[0,2,...] < 2**30, in[1,3,...] < 2**29 and
-//           in2[0,2,...] < 2**30, in2[1,3,...] < 2**29.
-// On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
-func p256Diff(out, in, in2 *[p256Limbs]uint32) {
-	var carry uint32
-
-	for i := 0; ; i++ {
-		out[i] = in[i] - in2[i]
-		out[i] += p256Zero31[i]
-		out[i] += carry
-		carry = out[i] >> 29
-		out[i] &= bottom29Bits
-
-		i++
-		if i == p256Limbs {
-			break
-		}
-
-		out[i] = in[i] - in2[i]
-		out[i] += p256Zero31[i]
-		out[i] += carry
-		carry = out[i] >> 28
-		out[i] &= bottom28Bits
-	}
-
-	p256ReduceCarry(out, carry)
-}
-
-// p256ReduceDegree sets out = tmp/R mod p where tmp contains 64-bit words with
-// the same 29,28,... bit positions as an field element.
-//
-// The values in field elements are in Montgomery form: x*R mod p where R =
-// 2**257. Since we just multiplied two Montgomery values together, the result
-// is x*y*R*R mod p. We wish to divide by R in order for the result also to be
-// in Montgomery form.
-//
-// On entry: tmp[i] < 2**64
-// On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29
-func p256ReduceDegree(out *[p256Limbs]uint32, tmp [17]uint64) {
-	// The following table may be helpful when reading this code:
-	//
-	// Limb number:   0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10...
-	// Width (bits):  29| 28| 29| 28| 29| 28| 29| 28| 29| 28| 29
-	// Start bit:     0 | 29| 57| 86|114|143|171|200|228|257|285
-	//   (odd phase): 0 | 28| 57| 85|114|142|171|199|228|256|285
-	var tmp2 [18]uint32
-	var carry, x, xMask uint32
-
-	// tmp contains 64-bit words with the same 29,28,29-bit positions as an
-	// field element. So the top of an element of tmp might overlap with
-	// another element two positions down. The following loop eliminates
-	// this overlap.
-	tmp2[0] = uint32(tmp[0]) & bottom29Bits
-
-	tmp2[1] = uint32(tmp[0]) >> 29
-	tmp2[1] |= (uint32(tmp[0]>>32) << 3) & bottom28Bits
-	tmp2[1] += uint32(tmp[1]) & bottom28Bits
-	carry = tmp2[1] >> 28
-	tmp2[1] &= bottom28Bits
-
-	for i := 2; i < 17; i++ {
-		tmp2[i] = (uint32(tmp[i-2] >> 32)) >> 25
-		tmp2[i] += (uint32(tmp[i-1])) >> 28
-		tmp2[i] += (uint32(tmp[i-1]>>32) << 4) & bottom29Bits
-		tmp2[i] += uint32(tmp[i]) & bottom29Bits
-		tmp2[i] += carry
-		carry = tmp2[i] >> 29
-		tmp2[i] &= bottom29Bits
-
-		i++
-		if i == 17 {
-			break
-		}
-		tmp2[i] = uint32(tmp[i-2]>>32) >> 25
-		tmp2[i] += uint32(tmp[i-1]) >> 29
-		tmp2[i] += ((uint32(tmp[i-1] >> 32)) << 3) & bottom28Bits
-		tmp2[i] += uint32(tmp[i]) & bottom28Bits
-		tmp2[i] += carry
-		carry = tmp2[i] >> 28
-		tmp2[i] &= bottom28Bits
-	}
-
-	tmp2[17] = uint32(tmp[15]>>32) >> 25
-	tmp2[17] += uint32(tmp[16]) >> 29
-	tmp2[17] += uint32(tmp[16]>>32) << 3
-	tmp2[17] += carry
-
-	// Montgomery elimination of terms:
-	//
-	// Since R is 2**257, we can divide by R with a bitwise shift if we can
-	// ensure that the right-most 257 bits are all zero. We can make that true
-	// by adding multiplies of p without affecting the value.
-	//
-	// So we eliminate limbs from right to left. Since the bottom 29 bits of p
-	// are all ones, then by adding tmp2[0]*p to tmp2 we'll make tmp2[0] == 0.
-	// We can do that for 8 further limbs and then right shift to eliminate the
-	// extra factor of R.
-	for i := 0; ; i += 2 {
-		tmp2[i+1] += tmp2[i] >> 29
-		x = tmp2[i] & bottom29Bits
-		xMask = nonZeroToAllOnes(x)
-		tmp2[i] = 0
-
-		// The bounds calculations for this loop are tricky. Each iteration of
-		// the loop eliminates two words by adding values to words to their
-		// right.
-		//
-		// The following table contains the amounts added to each word (as an
-		// offset from the value of i at the top of the loop). The amounts are
-		// accounted for from the first and second half of the loop separately
-		// and are written as, for example, 28 to mean a value <2**28.
-		//
-		// Word:                   3   4   5   6   7   8   9   10
-		// Added in top half:     28  11      29  21  29  28
-		//                                        28  29
-		//                                            29
-		// Added in bottom half:      29  10      28  21  28   28
-		//                                            29
-		//
-		// The value that is currently offset 7 will be offset 5 for the next
-		// iteration and then offset 3 for the iteration after that. Therefore
-		// the total value added will be the values added at 7, 5 and 3.
-		//
-		// The following table accumulates these values. The sums at the bottom
-		// are written as, for example, 29+28, to mean a value < 2**29+2**28.
-		//
-		// Word:                   3   4   5   6   7   8   9  10  11  12  13
-		//                        28  11  10  29  21  29  28  28  28  28  28
-		//                            29  28  11  28  29  28  29  28  29  28
-		//                                    29  28  21  21  29  21  29  21
-		//                                        10  29  28  21  28  21  28
-		//                                        28  29  28  29  28  29  28
-		//                                            11  10  29  10  29  10
-		//                                            29  28  11  28  11
-		//                                                    29      29
-		//                        --------------------------------------------
-		//                                                30+ 31+ 30+ 31+ 30+
-		//                                                28+ 29+ 28+ 29+ 21+
-		//                                                21+ 28+ 21+ 28+ 10
-		//                                                10  21+ 10  21+
-		//                                                    11      11
-		//
-		// So the greatest amount is added to tmp2[10] and tmp2[12]. If
-		// tmp2[10/12] has an initial value of <2**29, then the maximum value
-		// will be < 2**31 + 2**30 + 2**28 + 2**21 + 2**11, which is < 2**32,
-		// as required.
-		tmp2[i+3] += (x << 10) & bottom28Bits
-		tmp2[i+4] += (x >> 18)
-
-		tmp2[i+6] += (x << 21) & bottom29Bits
-		tmp2[i+7] += x >> 8
-
-		// At position 200, which is the starting bit position for word 7, we
-		// have a factor of 0xf000000 = 2**28 - 2**24.
-		tmp2[i+7] += 0x10000000 & xMask
-		tmp2[i+8] += (x - 1) & xMask
-		tmp2[i+7] -= (x << 24) & bottom28Bits
-		tmp2[i+8] -= x >> 4
-
-		tmp2[i+8] += 0x20000000 & xMask
-		tmp2[i+8] -= x
-		tmp2[i+8] += (x << 28) & bottom29Bits
-		tmp2[i+9] += ((x >> 1) - 1) & xMask
-
-		if i+1 == p256Limbs {
-			break
-		}
-		tmp2[i+2] += tmp2[i+1] >> 28
-		x = tmp2[i+1] & bottom28Bits
-		xMask = nonZeroToAllOnes(x)
-		tmp2[i+1] = 0
-
-		tmp2[i+4] += (x << 11) & bottom29Bits
-		tmp2[i+5] += (x >> 18)
-
-		tmp2[i+7] += (x << 21) & bottom28Bits
-		tmp2[i+8] += x >> 7
-
-		// At position 199, which is the starting bit of the 8th word when
-		// dealing with a context starting on an odd word, we have a factor of
-		// 0x1e000000 = 2**29 - 2**25. Since we have not updated i, the 8th
-		// word from i+1 is i+8.
-		tmp2[i+8] += 0x20000000 & xMask
-		tmp2[i+9] += (x - 1) & xMask
-		tmp2[i+8] -= (x << 25) & bottom29Bits
-		tmp2[i+9] -= x >> 4
-
-		tmp2[i+9] += 0x10000000 & xMask
-		tmp2[i+9] -= x
-		tmp2[i+10] += (x - 1) & xMask
-	}
-
-	// We merge the right shift with a carry chain. The words above 2**257 have
-	// widths of 28,29,... which we need to correct when copying them down.
-	carry = 0
-	for i := 0; i < 8; i++ {
-		// The maximum value of tmp2[i + 9] occurs on the first iteration and
-		// is < 2**30+2**29+2**28. Adding 2**29 (from tmp2[i + 10]) is
-		// therefore safe.
-		out[i] = tmp2[i+9]
-		out[i] += carry
-		out[i] += (tmp2[i+10] << 28) & bottom29Bits
-		carry = out[i] >> 29
-		out[i] &= bottom29Bits
-
-		i++
-		out[i] = tmp2[i+9] >> 1
-		out[i] += carry
-		carry = out[i] >> 28
-		out[i] &= bottom28Bits
-	}
-
-	out[8] = tmp2[17]
-	out[8] += carry
-	carry = out[8] >> 29
-	out[8] &= bottom29Bits
-
-	p256ReduceCarry(out, carry)
-}
-
-// p256Square sets out=in*in.
-//
-// On entry: in[0,2,...] < 2**30, in[1,3,...] < 2**29.
-// On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
-func p256Square(out, in *[p256Limbs]uint32) {
-	var tmp [17]uint64
-
-	tmp[0] = uint64(in[0]) * uint64(in[0])
-	tmp[1] = uint64(in[0]) * (uint64(in[1]) << 1)
-	tmp[2] = uint64(in[0])*(uint64(in[2])<<1) +
-		uint64(in[1])*(uint64(in[1])<<1)
-	tmp[3] = uint64(in[0])*(uint64(in[3])<<1) +
-		uint64(in[1])*(uint64(in[2])<<1)
-	tmp[4] = uint64(in[0])*(uint64(in[4])<<1) +
-		uint64(in[1])*(uint64(in[3])<<2) +
-		uint64(in[2])*uint64(in[2])
-	tmp[5] = uint64(in[0])*(uint64(in[5])<<1) +
-		uint64(in[1])*(uint64(in[4])<<1) +
-		uint64(in[2])*(uint64(in[3])<<1)
-	tmp[6] = uint64(in[0])*(uint64(in[6])<<1) +
-		uint64(in[1])*(uint64(in[5])<<2) +
-		uint64(in[2])*(uint64(in[4])<<1) +
-		uint64(in[3])*(uint64(in[3])<<1)
-	tmp[7] = uint64(in[0])*(uint64(in[7])<<1) +
-		uint64(in[1])*(uint64(in[6])<<1) +
-		uint64(in[2])*(uint64(in[5])<<1) +
-		uint64(in[3])*(uint64(in[4])<<1)
-	// tmp[8] has the greatest value of 2**61 + 2**60 + 2**61 + 2**60 + 2**60,
-	// which is < 2**64 as required.
-	tmp[8] = uint64(in[0])*(uint64(in[8])<<1) +
-		uint64(in[1])*(uint64(in[7])<<2) +
-		uint64(in[2])*(uint64(in[6])<<1) +
-		uint64(in[3])*(uint64(in[5])<<2) +
-		uint64(in[4])*uint64(in[4])
-	tmp[9] = uint64(in[1])*(uint64(in[8])<<1) +
-		uint64(in[2])*(uint64(in[7])<<1) +
-		uint64(in[3])*(uint64(in[6])<<1) +
-		uint64(in[4])*(uint64(in[5])<<1)
-	tmp[10] = uint64(in[2])*(uint64(in[8])<<1) +
-		uint64(in[3])*(uint64(in[7])<<2) +
-		uint64(in[4])*(uint64(in[6])<<1) +
-		uint64(in[5])*(uint64(in[5])<<1)
-	tmp[11] = uint64(in[3])*(uint64(in[8])<<1) +
-		uint64(in[4])*(uint64(in[7])<<1) +
-		uint64(in[5])*(uint64(in[6])<<1)
-	tmp[12] = uint64(in[4])*(uint64(in[8])<<1) +
-		uint64(in[5])*(uint64(in[7])<<2) +
-		uint64(in[6])*uint64(in[6])
-	tmp[13] = uint64(in[5])*(uint64(in[8])<<1) +
-		uint64(in[6])*(uint64(in[7])<<1)
-	tmp[14] = uint64(in[6])*(uint64(in[8])<<1) +
-		uint64(in[7])*(uint64(in[7])<<1)
-	tmp[15] = uint64(in[7]) * (uint64(in[8]) << 1)
-	tmp[16] = uint64(in[8]) * uint64(in[8])
-
-	p256ReduceDegree(out, tmp)
-}
-
-// p256Mul sets out=in*in2.
-//
-// On entry: in[0,2,...] < 2**30, in[1,3,...] < 2**29 and
-//           in2[0,2,...] < 2**30, in2[1,3,...] < 2**29.
-// On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
-func p256Mul(out, in, in2 *[p256Limbs]uint32) {
-	var tmp [17]uint64
-
-	tmp[0] = uint64(in[0]) * uint64(in2[0])
-	tmp[1] = uint64(in[0])*(uint64(in2[1])<<0) +
-		uint64(in[1])*(uint64(in2[0])<<0)
-	tmp[2] = uint64(in[0])*(uint64(in2[2])<<0) +
-		uint64(in[1])*(uint64(in2[1])<<1) +
-		uint64(in[2])*(uint64(in2[0])<<0)
-	tmp[3] = uint64(in[0])*(uint64(in2[3])<<0) +
-		uint64(in[1])*(uint64(in2[2])<<0) +
-		uint64(in[2])*(uint64(in2[1])<<0) +
-		uint64(in[3])*(uint64(in2[0])<<0)
-	tmp[4] = uint64(in[0])*(uint64(in2[4])<<0) +
-		uint64(in[1])*(uint64(in2[3])<<1) +
-		uint64(in[2])*(uint64(in2[2])<<0) +
-		uint64(in[3])*(uint64(in2[1])<<1) +
-		uint64(in[4])*(uint64(in2[0])<<0)
-	tmp[5] = uint64(in[0])*(uint64(in2[5])<<0) +
-		uint64(in[1])*(uint64(in2[4])<<0) +
-		uint64(in[2])*(uint64(in2[3])<<0) +
-		uint64(in[3])*(uint64(in2[2])<<0) +
-		uint64(in[4])*(uint64(in2[1])<<0) +
-		uint64(in[5])*(uint64(in2[0])<<0)
-	tmp[6] = uint64(in[0])*(uint64(in2[6])<<0) +
-		uint64(in[1])*(uint64(in2[5])<<1) +
-		uint64(in[2])*(uint64(in2[4])<<0) +
-		uint64(in[3])*(uint64(in2[3])<<1) +
-		uint64(in[4])*(uint64(in2[2])<<0) +
-		uint64(in[5])*(uint64(in2[1])<<1) +
-		uint64(in[6])*(uint64(in2[0])<<0)
-	tmp[7] = uint64(in[0])*(uint64(in2[7])<<0) +
-		uint64(in[1])*(uint64(in2[6])<<0) +
-		uint64(in[2])*(uint64(in2[5])<<0) +
-		uint64(in[3])*(uint64(in2[4])<<0) +
-		uint64(in[4])*(uint64(in2[3])<<0) +
-		uint64(in[5])*(uint64(in2[2])<<0) +
-		uint64(in[6])*(uint64(in2[1])<<0) +
-		uint64(in[7])*(uint64(in2[0])<<0)
-	// tmp[8] has the greatest value but doesn't overflow. See logic in
-	// p256Square.
-	tmp[8] = uint64(in[0])*(uint64(in2[8])<<0) +
-		uint64(in[1])*(uint64(in2[7])<<1) +
-		uint64(in[2])*(uint64(in2[6])<<0) +
-		uint64(in[3])*(uint64(in2[5])<<1) +
-		uint64(in[4])*(uint64(in2[4])<<0) +
-		uint64(in[5])*(uint64(in2[3])<<1) +
-		uint64(in[6])*(uint64(in2[2])<<0) +
-		uint64(in[7])*(uint64(in2[1])<<1) +
-		uint64(in[8])*(uint64(in2[0])<<0)
-	tmp[9] = uint64(in[1])*(uint64(in2[8])<<0) +
-		uint64(in[2])*(uint64(in2[7])<<0) +
-		uint64(in[3])*(uint64(in2[6])<<0) +
-		uint64(in[4])*(uint64(in2[5])<<0) +
-		uint64(in[5])*(uint64(in2[4])<<0) +
-		uint64(in[6])*(uint64(in2[3])<<0) +
-		uint64(in[7])*(uint64(in2[2])<<0) +
-		uint64(in[8])*(uint64(in2[1])<<0)
-	tmp[10] = uint64(in[2])*(uint64(in2[8])<<0) +
-		uint64(in[3])*(uint64(in2[7])<<1) +
-		uint64(in[4])*(uint64(in2[6])<<0) +
-		uint64(in[5])*(uint64(in2[5])<<1) +
-		uint64(in[6])*(uint64(in2[4])<<0) +
-		uint64(in[7])*(uint64(in2[3])<<1) +
-		uint64(in[8])*(uint64(in2[2])<<0)
-	tmp[11] = uint64(in[3])*(uint64(in2[8])<<0) +
-		uint64(in[4])*(uint64(in2[7])<<0) +
-		uint64(in[5])*(uint64(in2[6])<<0) +
-		uint64(in[6])*(uint64(in2[5])<<0) +
-		uint64(in[7])*(uint64(in2[4])<<0) +
-		uint64(in[8])*(uint64(in2[3])<<0)
-	tmp[12] = uint64(in[4])*(uint64(in2[8])<<0) +
-		uint64(in[5])*(uint64(in2[7])<<1) +
-		uint64(in[6])*(uint64(in2[6])<<0) +
-		uint64(in[7])*(uint64(in2[5])<<1) +
-		uint64(in[8])*(uint64(in2[4])<<0)
-	tmp[13] = uint64(in[5])*(uint64(in2[8])<<0) +
-		uint64(in[6])*(uint64(in2[7])<<0) +
-		uint64(in[7])*(uint64(in2[6])<<0) +
-		uint64(in[8])*(uint64(in2[5])<<0)
-	tmp[14] = uint64(in[6])*(uint64(in2[8])<<0) +
-		uint64(in[7])*(uint64(in2[7])<<1) +
-		uint64(in[8])*(uint64(in2[6])<<0)
-	tmp[15] = uint64(in[7])*(uint64(in2[8])<<0) +
-		uint64(in[8])*(uint64(in2[7])<<0)
-	tmp[16] = uint64(in[8]) * (uint64(in2[8]) << 0)
-
-	p256ReduceDegree(out, tmp)
-}
-
-func p256Assign(out, in *[p256Limbs]uint32) {
-	*out = *in
-}
-
-// p256Invert calculates |out| = |in|^{-1}
-//
-// Based on Fermat's Little Theorem:
-//   a^p = a (mod p)
-//   a^{p-1} = 1 (mod p)
-//   a^{p-2} = a^{-1} (mod p)
-func p256Invert(out, in *[p256Limbs]uint32) {
-	var ftmp, ftmp2 [p256Limbs]uint32
-
-	// each e_I will hold |in|^{2^I - 1}
-	var e2, e4, e8, e16, e32, e64 [p256Limbs]uint32
-
-	p256Square(&ftmp, in)     // 2^1
-	p256Mul(&ftmp, in, &ftmp) // 2^2 - 2^0
-	p256Assign(&e2, &ftmp)
-	p256Square(&ftmp, &ftmp)   // 2^3 - 2^1
-	p256Square(&ftmp, &ftmp)   // 2^4 - 2^2
-	p256Mul(&ftmp, &ftmp, &e2) // 2^4 - 2^0
-	p256Assign(&e4, &ftmp)
-	p256Square(&ftmp, &ftmp)   // 2^5 - 2^1
-	p256Square(&ftmp, &ftmp)   // 2^6 - 2^2
-	p256Square(&ftmp, &ftmp)   // 2^7 - 2^3
-	p256Square(&ftmp, &ftmp)   // 2^8 - 2^4
-	p256Mul(&ftmp, &ftmp, &e4) // 2^8 - 2^0
-	p256Assign(&e8, &ftmp)
-	for i := 0; i < 8; i++ {
-		p256Square(&ftmp, &ftmp)
-	} // 2^16 - 2^8
-	p256Mul(&ftmp, &ftmp, &e8) // 2^16 - 2^0
-	p256Assign(&e16, &ftmp)
-	for i := 0; i < 16; i++ {
-		p256Square(&ftmp, &ftmp)
-	} // 2^32 - 2^16
-	p256Mul(&ftmp, &ftmp, &e16) // 2^32 - 2^0
-	p256Assign(&e32, &ftmp)
-	for i := 0; i < 32; i++ {
-		p256Square(&ftmp, &ftmp)
-	} // 2^64 - 2^32
-	p256Assign(&e64, &ftmp)
-	p256Mul(&ftmp, &ftmp, in) // 2^64 - 2^32 + 2^0
-	for i := 0; i < 192; i++ {
-		p256Square(&ftmp, &ftmp)
-	} // 2^256 - 2^224 + 2^192
-
-	p256Mul(&ftmp2, &e64, &e32) // 2^64 - 2^0
-	for i := 0; i < 16; i++ {
-		p256Square(&ftmp2, &ftmp2)
-	} // 2^80 - 2^16
-	p256Mul(&ftmp2, &ftmp2, &e16) // 2^80 - 2^0
-	for i := 0; i < 8; i++ {
-		p256Square(&ftmp2, &ftmp2)
-	} // 2^88 - 2^8
-	p256Mul(&ftmp2, &ftmp2, &e8) // 2^88 - 2^0
-	for i := 0; i < 4; i++ {
-		p256Square(&ftmp2, &ftmp2)
-	} // 2^92 - 2^4
-	p256Mul(&ftmp2, &ftmp2, &e4) // 2^92 - 2^0
-	p256Square(&ftmp2, &ftmp2)   // 2^93 - 2^1
-	p256Square(&ftmp2, &ftmp2)   // 2^94 - 2^2
-	p256Mul(&ftmp2, &ftmp2, &e2) // 2^94 - 2^0
-	p256Square(&ftmp2, &ftmp2)   // 2^95 - 2^1
-	p256Square(&ftmp2, &ftmp2)   // 2^96 - 2^2
-	p256Mul(&ftmp2, &ftmp2, in)  // 2^96 - 3
-
-	p256Mul(out, &ftmp2, &ftmp) // 2^256 - 2^224 + 2^192 + 2^96 - 3
-}
-
-// p256Scalar3 sets out=3*out.
-//
-// On entry: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
-// On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
-func p256Scalar3(out *[p256Limbs]uint32) {
-	var carry uint32
-
-	for i := 0; ; i++ {
-		out[i] *= 3
-		out[i] += carry
-		carry = out[i] >> 29
-		out[i] &= bottom29Bits
-
-		i++
-		if i == p256Limbs {
-			break
-		}
-
-		out[i] *= 3
-		out[i] += carry
-		carry = out[i] >> 28
-		out[i] &= bottom28Bits
-	}
-
-	p256ReduceCarry(out, carry)
-}
-
-// p256Scalar4 sets out=4*out.
-//
-// On entry: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
-// On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
-func p256Scalar4(out *[p256Limbs]uint32) {
-	var carry, nextCarry uint32
-
-	for i := 0; ; i++ {
-		nextCarry = out[i] >> 27
-		out[i] <<= 2
-		out[i] &= bottom29Bits
-		out[i] += carry
-		carry = nextCarry + (out[i] >> 29)
-		out[i] &= bottom29Bits
-
-		i++
-		if i == p256Limbs {
-			break
-		}
-		nextCarry = out[i] >> 26
-		out[i] <<= 2
-		out[i] &= bottom28Bits
-		out[i] += carry
-		carry = nextCarry + (out[i] >> 28)
-		out[i] &= bottom28Bits
-	}
-
-	p256ReduceCarry(out, carry)
-}
-
-// p256Scalar8 sets out=8*out.
-//
-// On entry: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
-// On exit: out[0,2,...] < 2**30, out[1,3,...] < 2**29.
-func p256Scalar8(out *[p256Limbs]uint32) {
-	var carry, nextCarry uint32
-
-	for i := 0; ; i++ {
-		nextCarry = out[i] >> 26
-		out[i] <<= 3
-		out[i] &= bottom29Bits
-		out[i] += carry
-		carry = nextCarry + (out[i] >> 29)
-		out[i] &= bottom29Bits
-
-		i++
-		if i == p256Limbs {
-			break
-		}
-		nextCarry = out[i] >> 25
-		out[i] <<= 3
-		out[i] &= bottom28Bits
-		out[i] += carry
-		carry = nextCarry + (out[i] >> 28)
-		out[i] &= bottom28Bits
-	}
-
-	p256ReduceCarry(out, carry)
-}
-
-// Group operations:
-//
-// Elements of the elliptic curve group are represented in Jacobian
-// coordinates: (x, y, z). An affine point (x', y') is x'=x/z**2, y'=y/z**3 in
-// Jacobian form.
-
-// p256PointDouble sets {xOut,yOut,zOut} = 2*{x,y,z}.
-//
-// See http://www.hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-0.html#doubling-dbl-2009-l
-func p256PointDouble(xOut, yOut, zOut, x, y, z *[p256Limbs]uint32) {
-	var delta, gamma, alpha, beta, tmp, tmp2 [p256Limbs]uint32
-
-	p256Square(&delta, z)
-	p256Square(&gamma, y)
-	p256Mul(&beta, x, &gamma)
-
-	p256Sum(&tmp, x, &delta)
-	p256Diff(&tmp2, x, &delta)
-	p256Mul(&alpha, &tmp, &tmp2)
-	p256Scalar3(&alpha)
-
-	p256Sum(&tmp, y, z)
-	p256Square(&tmp, &tmp)
-	p256Diff(&tmp, &tmp, &gamma)
-	p256Diff(zOut, &tmp, &delta)
-
-	p256Scalar4(&beta)
-	p256Square(xOut, &alpha)
-	p256Diff(xOut, xOut, &beta)
-	p256Diff(xOut, xOut, &beta)
-
-	p256Diff(&tmp, &beta, xOut)
-	p256Mul(&tmp, &alpha, &tmp)
-	p256Square(&tmp2, &gamma)
-	p256Scalar8(&tmp2)
-	p256Diff(yOut, &tmp, &tmp2)
-}
-
-// p256PointAddMixed sets {xOut,yOut,zOut} = {x1,y1,z1} + {x2,y2,1}.
-// (i.e. the second point is affine.)
-//
-// See http://www.hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-0.html#addition-add-2007-bl
-//
-// Note that this function does not handle P+P, infinity+P nor P+infinity
-// correctly.
-func p256PointAddMixed(xOut, yOut, zOut, x1, y1, z1, x2, y2 *[p256Limbs]uint32) {
-	var z1z1, z1z1z1, s2, u2, h, i, j, r, rr, v, tmp [p256Limbs]uint32
-
-	p256Square(&z1z1, z1)
-	p256Sum(&tmp, z1, z1)
-
-	p256Mul(&u2, x2, &z1z1)
-	p256Mul(&z1z1z1, z1, &z1z1)
-	p256Mul(&s2, y2, &z1z1z1)
-	p256Diff(&h, &u2, x1)
-	p256Sum(&i, &h, &h)
-	p256Square(&i, &i)
-	p256Mul(&j, &h, &i)
-	p256Diff(&r, &s2, y1)
-	p256Sum(&r, &r, &r)
-	p256Mul(&v, x1, &i)
-
-	p256Mul(zOut, &tmp, &h)
-	p256Square(&rr, &r)
-	p256Diff(xOut, &rr, &j)
-	p256Diff(xOut, xOut, &v)
-	p256Diff(xOut, xOut, &v)
-
-	p256Diff(&tmp, &v, xOut)
-	p256Mul(yOut, &tmp, &r)
-	p256Mul(&tmp, y1, &j)
-	p256Diff(yOut, yOut, &tmp)
-	p256Diff(yOut, yOut, &tmp)
-}
-
-// p256PointAdd sets {xOut,yOut,zOut} = {x1,y1,z1} + {x2,y2,z2}.
-//
-// See http://www.hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-0.html#addition-add-2007-bl
-//
-// Note that this function does not handle P+P, infinity+P nor P+infinity
-// correctly.
-func p256PointAdd(xOut, yOut, zOut, x1, y1, z1, x2, y2, z2 *[p256Limbs]uint32) {
-	var z1z1, z1z1z1, z2z2, z2z2z2, s1, s2, u1, u2, h, i, j, r, rr, v, tmp [p256Limbs]uint32
-
-	p256Square(&z1z1, z1)
-	p256Square(&z2z2, z2)
-	p256Mul(&u1, x1, &z2z2)
-
-	p256Sum(&tmp, z1, z2)
-	p256Square(&tmp, &tmp)
-	p256Diff(&tmp, &tmp, &z1z1)
-	p256Diff(&tmp, &tmp, &z2z2)
-
-	p256Mul(&z2z2z2, z2, &z2z2)
-	p256Mul(&s1, y1, &z2z2z2)
-
-	p256Mul(&u2, x2, &z1z1)
-	p256Mul(&z1z1z1, z1, &z1z1)
-	p256Mul(&s2, y2, &z1z1z1)
-	p256Diff(&h, &u2, &u1)
-	p256Sum(&i, &h, &h)
-	p256Square(&i, &i)
-	p256Mul(&j, &h, &i)
-	p256Diff(&r, &s2, &s1)
-	p256Sum(&r, &r, &r)
-	p256Mul(&v, &u1, &i)
-
-	p256Mul(zOut, &tmp, &h)
-	p256Square(&rr, &r)
-	p256Diff(xOut, &rr, &j)
-	p256Diff(xOut, xOut, &v)
-	p256Diff(xOut, xOut, &v)
-
-	p256Diff(&tmp, &v, xOut)
-	p256Mul(yOut, &tmp, &r)
-	p256Mul(&tmp, &s1, &j)
-	p256Diff(yOut, yOut, &tmp)
-	p256Diff(yOut, yOut, &tmp)
-}
-
-// p256CopyConditional sets out=in if mask = 0xffffffff in constant time.
-//
-// On entry: mask is either 0 or 0xffffffff.
-func p256CopyConditional(out, in *[p256Limbs]uint32, mask uint32) {
-	for i := 0; i < p256Limbs; i++ {
-		tmp := mask & (in[i] ^ out[i])
-		out[i] ^= tmp
-	}
-}
-
-// p256SelectAffinePoint sets {out_x,out_y} to the index'th entry of table.
-// On entry: index < 16, table[0] must be zero.
-func p256SelectAffinePoint(xOut, yOut *[p256Limbs]uint32, table []uint32, index uint32) {
-	for i := range xOut {
-		xOut[i] = 0
-	}
-	for i := range yOut {
-		yOut[i] = 0
-	}
-
-	for i := uint32(1); i < 16; i++ {
-		mask := i ^ index
-		mask |= mask >> 2
-		mask |= mask >> 1
-		mask &= 1
-		mask--
-		for j := range xOut {
-			xOut[j] |= table[0] & mask
-			table = table[1:]
-		}
-		for j := range yOut {
-			yOut[j] |= table[0] & mask
-			table = table[1:]
-		}
-	}
-}
-
-// p256SelectJacobianPoint sets {out_x,out_y,out_z} to the index'th entry of
-// table.
-// On entry: index < 16, table[0] must be zero.
-func p256SelectJacobianPoint(xOut, yOut, zOut *[p256Limbs]uint32, table *[16][3][p256Limbs]uint32, index uint32) {
-	for i := range xOut {
-		xOut[i] = 0
-	}
-	for i := range yOut {
-		yOut[i] = 0
-	}
-	for i := range zOut {
-		zOut[i] = 0
-	}
-
-	// The implicit value at index 0 is all zero. We don't need to perform that
-	// iteration of the loop because we already set out_* to zero.
-	for i := uint32(1); i < 16; i++ {
-		mask := i ^ index
-		mask |= mask >> 2
-		mask |= mask >> 1
-		mask &= 1
-		mask--
-		for j := range xOut {
-			xOut[j] |= table[i][0][j] & mask
-		}
-		for j := range yOut {
-			yOut[j] |= table[i][1][j] & mask
-		}
-		for j := range zOut {
-			zOut[j] |= table[i][2][j] & mask
-		}
-	}
-}
-
-// p256GetBit returns the bit'th bit of scalar.
-func p256GetBit(scalar *[32]uint8, bit uint) uint32 {
-	return uint32(((scalar[bit>>3]) >> (bit & 7)) & 1)
-}
-
-// p256ScalarBaseMult sets {xOut,yOut,zOut} = scalar*G where scalar is a
-// little-endian number. Note that the value of scalar must be less than the
-// order of the group.
-func p256ScalarBaseMult(xOut, yOut, zOut *[p256Limbs]uint32, scalar *[32]uint8) {
-	nIsInfinityMask := ^uint32(0)
-	var pIsNoninfiniteMask, mask, tableOffset uint32
-	var px, py, tx, ty, tz [p256Limbs]uint32
-
-	for i := range xOut {
-		xOut[i] = 0
-	}
-	for i := range yOut {
-		yOut[i] = 0
-	}
-	for i := range zOut {
-		zOut[i] = 0
-	}
-
-	// The loop adds bits at positions 0, 64, 128 and 192, followed by
-	// positions 32,96,160 and 224 and does this 32 times.
-	for i := uint(0); i < 32; i++ {
-		if i != 0 {
-			p256PointDouble(xOut, yOut, zOut, xOut, yOut, zOut)
-		}
-		tableOffset = 0
-		for j := uint(0); j <= 32; j += 32 {
-			bit0 := p256GetBit(scalar, 31-i+j)
-			bit1 := p256GetBit(scalar, 95-i+j)
-			bit2 := p256GetBit(scalar, 159-i+j)
-			bit3 := p256GetBit(scalar, 223-i+j)
-			index := bit0 | (bit1 << 1) | (bit2 << 2) | (bit3 << 3)
-
-			p256SelectAffinePoint(&px, &py, p256Precomputed[tableOffset:], index)
-			tableOffset += 30 * p256Limbs
-
-			// Since scalar is less than the order of the group, we know that
-			// {xOut,yOut,zOut} != {px,py,1}, unless both are zero, which we handle
-			// below.
-			p256PointAddMixed(&tx, &ty, &tz, xOut, yOut, zOut, &px, &py)
-			// The result of pointAddMixed is incorrect if {xOut,yOut,zOut} is zero
-			// (a.k.a.  the point at infinity). We handle that situation by
-			// copying the point from the table.
-			p256CopyConditional(xOut, &px, nIsInfinityMask)
-			p256CopyConditional(yOut, &py, nIsInfinityMask)
-			p256CopyConditional(zOut, &p256One, nIsInfinityMask)
-
-			// Equally, the result is also wrong if the point from the table is
-			// zero, which happens when the index is zero. We handle that by
-			// only copying from {tx,ty,tz} to {xOut,yOut,zOut} if index != 0.
-			pIsNoninfiniteMask = nonZeroToAllOnes(index)
-			mask = pIsNoninfiniteMask & ^nIsInfinityMask
-			p256CopyConditional(xOut, &tx, mask)
-			p256CopyConditional(yOut, &ty, mask)
-			p256CopyConditional(zOut, &tz, mask)
-			// If p was not zero, then n is now non-zero.
-			nIsInfinityMask &= ^pIsNoninfiniteMask
-		}
-	}
-}
-
-// p256PointToAffine converts a Jacobian point to an affine point. If the input
-// is the point at infinity then it returns (0, 0) in constant time.
-func p256PointToAffine(xOut, yOut, x, y, z *[p256Limbs]uint32) {
-	var zInv, zInvSq [p256Limbs]uint32
-
-	p256Invert(&zInv, z)
-	p256Square(&zInvSq, &zInv)
-	p256Mul(xOut, x, &zInvSq)
-	p256Mul(&zInv, &zInv, &zInvSq)
-	p256Mul(yOut, y, &zInv)
-}
-
-// p256ToAffine returns a pair of *big.Int containing the affine representation
-// of {x,y,z}.
-func p256ToAffine(x, y, z *[p256Limbs]uint32) (xOut, yOut *big.Int) {
-	var xx, yy [p256Limbs]uint32
-	p256PointToAffine(&xx, &yy, x, y, z)
-	return p256ToBig(&xx), p256ToBig(&yy)
-}
-
-// p256ScalarMult sets {xOut,yOut,zOut} = scalar*{x,y}.
-func p256ScalarMult(xOut, yOut, zOut, x, y *[p256Limbs]uint32, scalar *[32]uint8) {
-	var px, py, pz, tx, ty, tz [p256Limbs]uint32
-	var precomp [16][3][p256Limbs]uint32
-	var nIsInfinityMask, index, pIsNoninfiniteMask, mask uint32
-
-	// We precompute 0,1,2,... times {x,y}.
-	precomp[1][0] = *x
-	precomp[1][1] = *y
-	precomp[1][2] = p256One
-
-	for i := 2; i < 16; i += 2 {
-		p256PointDouble(&precomp[i][0], &precomp[i][1], &precomp[i][2], &precomp[i/2][0], &precomp[i/2][1], &precomp[i/2][2])
-		p256PointAddMixed(&precomp[i+1][0], &precomp[i+1][1], &precomp[i+1][2], &precomp[i][0], &precomp[i][1], &precomp[i][2], x, y)
-	}
-
-	for i := range xOut {
-		xOut[i] = 0
-	}
-	for i := range yOut {
-		yOut[i] = 0
-	}
-	for i := range zOut {
-		zOut[i] = 0
-	}
-	nIsInfinityMask = ^uint32(0)
-
-	// We add in a window of four bits each iteration and do this 64 times.
-	for i := 0; i < 64; i++ {
-		if i != 0 {
-			p256PointDouble(xOut, yOut, zOut, xOut, yOut, zOut)
-			p256PointDouble(xOut, yOut, zOut, xOut, yOut, zOut)
-			p256PointDouble(xOut, yOut, zOut, xOut, yOut, zOut)
-			p256PointDouble(xOut, yOut, zOut, xOut, yOut, zOut)
-		}
-
-		index = uint32(scalar[31-i/2])
-		if (i & 1) == 1 {
-			index &= 15
-		} else {
-			index >>= 4
-		}
-
-		// See the comments in scalarBaseMult about handling infinities.
-		p256SelectJacobianPoint(&px, &py, &pz, &precomp, index)
-		p256PointAdd(&tx, &ty, &tz, xOut, yOut, zOut, &px, &py, &pz)
-		p256CopyConditional(xOut, &px, nIsInfinityMask)
-		p256CopyConditional(yOut, &py, nIsInfinityMask)
-		p256CopyConditional(zOut, &pz, nIsInfinityMask)
-
-		pIsNoninfiniteMask = nonZeroToAllOnes(index)
-		mask = pIsNoninfiniteMask & ^nIsInfinityMask
-		p256CopyConditional(xOut, &tx, mask)
-		p256CopyConditional(yOut, &ty, mask)
-		p256CopyConditional(zOut, &tz, mask)
-		nIsInfinityMask &= ^pIsNoninfiniteMask
-	}
-}
-
-// p256FromBig sets out = R*in.
-func p256FromBig(out *[p256Limbs]uint32, in *big.Int) {
-	tmp := new(big.Int).Lsh(in, 257)
-	tmp.Mod(tmp, p256.P)
-
-	for i := 0; i < p256Limbs; i++ {
-		if bits := tmp.Bits(); len(bits) > 0 {
-			out[i] = uint32(bits[0]) & bottom29Bits
-		} else {
-			out[i] = 0
-		}
-		tmp.Rsh(tmp, 29)
-
-		i++
-		if i == p256Limbs {
-			break
-		}
-
-		if bits := tmp.Bits(); len(bits) > 0 {
-			out[i] = uint32(bits[0]) & bottom28Bits
-		} else {
-			out[i] = 0
-		}
-		tmp.Rsh(tmp, 28)
-	}
-}
-
-// p256ToBig returns a *big.Int containing the value of in.
-func p256ToBig(in *[p256Limbs]uint32) *big.Int {
-	result, tmp := new(big.Int), new(big.Int)
-
-	result.SetInt64(int64(in[p256Limbs-1]))
-	for i := p256Limbs - 2; i >= 0; i-- {
-		if (i & 1) == 0 {
-			result.Lsh(result, 29)
-		} else {
-			result.Lsh(result, 28)
-		}
-		tmp.SetInt64(int64(in[i]))
-		result.Add(result, tmp)
-	}
-
-	result.Mul(result, p256RInverse)
-	result.Mod(result, p256.P)
-	return result
-}