Viel neues

This commit is contained in:
Sven Steinert
2026-04-30 12:06:00 +02:00
parent 118809bfae
commit fce31ebcd7
1274 changed files with 181255 additions and 0 deletions

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<?php
/**
* Curve methods common to all curves
*
* PHP version 5 and 7
*
* @author Jim Wigginton <terrafrost@php.net>
* @copyright 2017 Jim Wigginton
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @link http://pear.php.net/package/Math_BigInteger
*/
declare(strict_types=1);
namespace phpseclib3\Crypt\EC\BaseCurves;
use phpseclib3\Exception\RangeException;
use phpseclib3\Exception\RuntimeException;
use phpseclib3\Math\BigInteger;
use phpseclib3\Math\FiniteField\Integer;
/**
* Base
*
* @author Jim Wigginton <terrafrost@php.net>
*/
abstract class Base
{
/**
* The Order
*
* @var BigInteger
*/
protected $order;
/**
* Finite Field Integer factory
*
* @var Integer
*/
protected $factory;
/**
* Returns a random integer
*
* @return object
*/
public function randomInteger()
{
return $this->factory->randomInteger();
}
/**
* Converts a BigInteger to a \phpseclib3\Math\FiniteField\Integer integer
*
* @return object
*/
public function convertInteger(BigInteger $x)
{
return $this->factory->newInteger($x);
}
/**
* Returns the length, in bytes, of the modulo
*
* @return Integer
*/
public function getLengthInBytes(): int
{
return $this->factory->getLengthInBytes();
}
/**
* Returns the length, in bits, of the modulo
*
* @return Integer
*/
public function getLength(): int
{
return $this->factory->getLength();
}
/**
* Multiply a point on the curve by a scalar
*
* Uses the montgomery ladder technique as described here:
*
* https://en.wikipedia.org/wiki/Elliptic_curve_point_multiplication#Montgomery_ladder
* https://github.com/phpecc/phpecc/issues/16#issuecomment-59176772
*/
public function multiplyPoint(array $p, BigInteger $d): array
{
$alreadyInternal = isset($p[2]);
$r = $alreadyInternal ?
[[], $p] :
[[], $this->convertToInternal($p)];
$d = $d->toBits();
for ($i = 0; $i < strlen($d); $i++) {
$d_i = (int) $d[$i];
$r[1 - $d_i] = $this->addPoint($r[0], $r[1]);
$r[$d_i] = $this->doublePoint($r[$d_i]);
}
return $alreadyInternal ? $r[0] : $this->convertToAffine($r[0]);
}
/**
* Creates a random scalar multiplier
*/
public function createRandomMultiplier(): BigInteger
{
static $one;
if (!isset($one)) {
$one = new BigInteger(1);
}
return BigInteger::randomRange($one, $this->order->subtract($one));
}
/**
* Performs range check
*/
public function rangeCheck(BigInteger $x): void
{
static $zero;
if (!isset($zero)) {
$zero = new BigInteger();
}
if (!isset($this->order)) {
throw new RuntimeException('setOrder needs to be called before this method');
}
if ($x->compare($this->order) > 0 || $x->compare($zero) <= 0) {
throw new RangeException('x must be between 1 and the order of the curve');
}
}
/**
* Sets the Order
*/
public function setOrder(BigInteger $order): void
{
$this->order = $order;
}
/**
* Returns the Order
*/
public function getOrder(): BigInteger
{
return $this->order;
}
/**
* Use a custom defined modular reduction function
*
* @return object
*/
public function setReduction(callable $func)
{
$this->factory->setReduction($func);
}
/**
* Returns the affine point
*
* @return object[]
*/
public function convertToAffine(array $p): array
{
return $p;
}
/**
* Converts an affine point to a jacobian coordinate
*
* @return object[]
*/
public function convertToInternal(array $p): array
{
return $p;
}
/**
* Negates a point
*
* @return object[]
*/
public function negatePoint(array $p): array
{
$temp = [
$p[0],
$p[1]->negate(),
];
if (isset($p[2])) {
$temp[] = $p[2];
}
return $temp;
}
/**
* Multiply and Add Points
*
* @return int[]
*/
public function multiplyAddPoints(array $points, array $scalars): array
{
$p1 = $this->convertToInternal($points[0]);
$p2 = $this->convertToInternal($points[1]);
$p1 = $this->multiplyPoint($p1, $scalars[0]);
$p2 = $this->multiplyPoint($p2, $scalars[1]);
$r = $this->addPoint($p1, $p2);
return $this->convertToAffine($r);
}
}

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<?php
/**
* Curves over y^2 + x*y = x^3 + a*x^2 + b
*
* These are curves used in SEC 2 over prime fields: http://www.secg.org/SEC2-Ver-1.0.pdf
* The curve is a weierstrass curve with a[3] and a[2] set to 0.
*
* Uses Jacobian Coordinates for speed if able:
*
* https://en.wikipedia.org/wiki/Jacobian_curve
* https://en.wikibooks.org/wiki/Cryptography/Prime_Curve/Jacobian_Coordinates
*
* PHP version 5 and 7
*
* @author Jim Wigginton <terrafrost@php.net>
* @copyright 2017 Jim Wigginton
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @link http://pear.php.net/package/Math_BigInteger
*/
declare(strict_types=1);
namespace phpseclib3\Crypt\EC\BaseCurves;
use phpseclib3\Exception\RuntimeException;
use phpseclib3\Exception\UnexpectedValueException;
use phpseclib3\Math\BigInteger;
use phpseclib3\Math\BinaryField;
use phpseclib3\Math\BinaryField\Integer as BinaryInteger;
use phpseclib3\Math\PrimeField\Integer;
/**
* Curves over y^2 + x*y = x^3 + a*x^2 + b
*
* @author Jim Wigginton <terrafrost@php.net>
*/
class Binary extends Base
{
/**
* Binary Field Integer factory
*
* @var BinaryField
*/
protected $factory;
/**
* Cofficient for x^1
*
* @var object
*/
protected $a;
/**
* Cofficient for x^0
*
* @var object
*/
protected $b;
/**
* Base Point
*
* @var object
*/
protected $p;
/**
* The number one over the specified finite field
*
* @var object
*/
protected $one;
/**
* The modulo
*
* @var array
*/
protected $modulo;
/**
* The Order
*
* @var BigInteger
*/
protected $order;
/**
* Sets the modulo
*/
public function setModulo(int ...$modulo): void
{
$this->modulo = $modulo;
$this->factory = new BinaryField(...$modulo);
$this->one = $this->factory->newInteger("\1");
}
/**
* Set coefficients a and b
*/
public function setCoefficients(string $a, string $b): void
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
$this->a = $this->factory->newInteger(pack('H*', $a));
$this->b = $this->factory->newInteger(pack('H*', $b));
}
/**
* Set x and y coordinates for the base point
*
* @param string|BinaryInteger $x
* @param string|BinaryInteger $y
*/
public function setBasePoint($x, $y): void
{
switch (true) {
case !is_string($x) && !$x instanceof BinaryInteger:
throw new UnexpectedValueException('Argument 1 passed to Binary::setBasePoint() must be a string or an instance of BinaryField\Integer');
case !is_string($y) && !$y instanceof BinaryInteger:
throw new UnexpectedValueException('Argument 2 passed to Binary::setBasePoint() must be a string or an instance of BinaryField\Integer');
}
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
$this->p = [
is_string($x) ? $this->factory->newInteger(pack('H*', $x)) : $x,
is_string($y) ? $this->factory->newInteger(pack('H*', $y)) : $y,
];
}
/**
* Retrieve the base point as an array
*
* @return array
*/
public function getBasePoint()
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
/*
if (!isset($this->p)) {
throw new \phpseclib3\Exception\RuntimeException('setBasePoint needs to be called before this method');
}
*/
return $this->p;
}
/**
* Adds two points on the curve
*
* @return FiniteField[]
*/
public function addPoint(array $p, array $q): array
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
if (!count($p) || !count($q)) {
if (count($q)) {
return $q;
}
if (count($p)) {
return $p;
}
return [];
}
if (!isset($p[2]) || !isset($q[2])) {
throw new RuntimeException('Affine coordinates need to be manually converted to "Jacobi" coordinates or vice versa');
}
if ($p[0]->equals($q[0])) {
return !$p[1]->equals($q[1]) ? [] : $this->doublePoint($p);
}
// formulas from http://hyperelliptic.org/EFD/g12o/auto-shortw-jacobian.html
[$x1, $y1, $z1] = $p;
[$x2, $y2, $z2] = $q;
$o1 = $z1->multiply($z1);
$b = $x2->multiply($o1);
if ($z2->equals($this->one)) {
$d = $y2->multiply($o1)->multiply($z1);
$e = $x1->add($b);
$f = $y1->add($d);
$z3 = $e->multiply($z1);
$h = $f->multiply($x2)->add($z3->multiply($y2));
$i = $f->add($z3);
$g = $z3->multiply($z3);
$p1 = $this->a->multiply($g);
$p2 = $f->multiply($i);
$p3 = $e->multiply($e)->multiply($e);
$x3 = $p1->add($p2)->add($p3);
$y3 = $i->multiply($x3)->add($g->multiply($h));
return [$x3, $y3, $z3];
}
$o2 = $z2->multiply($z2);
$a = $x1->multiply($o2);
$c = $y1->multiply($o2)->multiply($z2);
$d = $y2->multiply($o1)->multiply($z1);
$e = $a->add($b);
$f = $c->add($d);
$g = $e->multiply($z1);
$h = $f->multiply($x2)->add($g->multiply($y2));
$z3 = $g->multiply($z2);
$i = $f->add($z3);
$p1 = $this->a->multiply($z3->multiply($z3));
$p2 = $f->multiply($i);
$p3 = $e->multiply($e)->multiply($e);
$x3 = $p1->add($p2)->add($p3);
$y3 = $i->multiply($x3)->add($g->multiply($g)->multiply($h));
return [$x3, $y3, $z3];
}
/**
* Doubles a point on a curve
*
* @return FiniteField[]
*/
public function doublePoint(array $p): array
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
if (!count($p)) {
return [];
}
if (!isset($p[2])) {
throw new RuntimeException('Affine coordinates need to be manually converted to "Jacobi" coordinates or vice versa');
}
// formulas from http://hyperelliptic.org/EFD/g12o/auto-shortw-jacobian.html
[$x1, $y1, $z1] = $p;
$a = $x1->multiply($x1);
$b = $a->multiply($a);
if ($z1->equals($this->one)) {
$x3 = $b->add($this->b);
$z3 = clone $x1;
$p1 = $a->add($y1)->add($z3)->multiply($this->b);
$p2 = $a->add($y1)->multiply($b);
$y3 = $p1->add($p2);
return [$x3, $y3, $z3];
}
$c = $z1->multiply($z1);
$d = $c->multiply($c);
$x3 = $b->add($this->b->multiply($d->multiply($d)));
$z3 = $x1->multiply($c);
$p1 = $b->multiply($z3);
$p2 = $a->add($y1->multiply($z1))->add($z3)->multiply($x3);
$y3 = $p1->add($p2);
return [$x3, $y3, $z3];
}
/**
* Returns the X coordinate and the derived Y coordinate
*
* Not supported because it is covered by patents.
* Quoting https://www.openssl.org/docs/man1.1.0/apps/ecparam.html ,
*
* "Due to patent issues the compressed option is disabled by default for binary curves
* and can be enabled by defining the preprocessor macro OPENSSL_EC_BIN_PT_COMP at
* compile time."
*/
public function derivePoint($m): array
{
throw new RuntimeException('Point compression on binary finite field elliptic curves is not supported');
}
/**
* Tests whether or not the x / y values satisfy the equation
*
* @return boolean
*/
public function verifyPoint(array $p): bool
{
[$x, $y] = $p;
$lhs = $y->multiply($y);
$lhs = $lhs->add($x->multiply($y));
$x2 = $x->multiply($x);
$x3 = $x2->multiply($x);
$rhs = $x3->add($this->a->multiply($x2))->add($this->b);
return $lhs->equals($rhs);
}
/**
* Returns the modulo
*/
public function getModulo(): array
{
return $this->modulo;
}
/**
* Returns the a coefficient
*
* @return Integer
*/
public function getA()
{
return $this->a;
}
/**
* Returns the a coefficient
*
* @return Integer
*/
public function getB()
{
return $this->b;
}
/**
* Returns the affine point
*
* A Jacobian Coordinate is of the form (x, y, z).
* To convert a Jacobian Coordinate to an Affine Point
* you do (x / z^2, y / z^3)
*
* @return Integer[]
*/
public function convertToAffine(array $p): array
{
if (!isset($p[2])) {
return $p;
}
[$x, $y, $z] = $p;
$z = $this->one->divide($z);
$z2 = $z->multiply($z);
return [
$x->multiply($z2),
$y->multiply($z2)->multiply($z),
];
}
/**
* Converts an affine point to a jacobian coordinate
*
* @return Integer[]
*/
public function convertToInternal(array $p): array
{
if (isset($p[2])) {
return $p;
}
$p[2] = clone $this->one;
$p['fresh'] = true;
return $p;
}
}

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<?php
/**
* Generalized Koblitz Curves over y^2 = x^3 + b.
*
* According to http://www.secg.org/SEC2-Ver-1.0.pdf Koblitz curves are over the GF(2**m)
* finite field. Both the $a$ and $b$ coefficients are either 0 or 1. However, SEC2
* generalizes the definition to include curves over GF(P) "which possess an efficiently
* computable endomorphism".
*
* For these generalized Koblitz curves $b$ doesn't have to be 0 or 1. Whether or not $a$
* has any restrictions on it is unclear, however, for all the GF(P) Koblitz curves defined
* in SEC2 v1.0 $a$ is $0$ so all of the methods defined herein will assume that it is.
*
* I suppose we could rename the $b$ coefficient to $a$, however, the documentation refers
* to $b$ so we'll just keep it.
*
* If a later version of SEC2 comes out wherein some $a$ values are non-zero we can create a
* new method for those. eg. KoblitzA1Prime.php or something.
*
* PHP version 5 and 7
*
* @author Jim Wigginton <terrafrost@php.net>
* @copyright 2017 Jim Wigginton
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @link http://pear.php.net/package/Math_BigInteger
*/
declare(strict_types=1);
namespace phpseclib3\Crypt\EC\BaseCurves;
use phpseclib3\Math\BigInteger;
use phpseclib3\Math\PrimeField;
/**
* Curves over y^2 = x^3 + b
*
* @author Jim Wigginton <terrafrost@php.net>
*/
class KoblitzPrime extends Prime
{
/**
* Basis
*
* @var list<array{a: BigInteger, b: BigInteger}>
*/
public $basis;
/**
* Beta
*
* @var PrimeField\Integer
*/
public $beta;
// don't overwrite setCoefficients() with one that only accepts one parameter so that
// one might be able to switch between KoblitzPrime and Prime more easily (for benchmarking
// purposes).
/**
* Multiply and Add Points
*
* Uses a efficiently computable endomorphism to achieve a slight speedup
*
* Adapted from:
* https://github.com/indutny/elliptic/blob/725bd91/lib/elliptic/curve/short.js#L219
*
* @return int[]
*/
public function multiplyAddPoints(array $points, array $scalars): array
{
static $zero, $one, $two;
if (!isset($two)) {
$two = new BigInteger(2);
$one = new BigInteger(1);
}
if (!isset($this->beta)) {
// get roots
$inv = $this->one->divide($this->two)->negate();
$s = $this->three->negate()->squareRoot()->multiply($inv);
$betas = [
$inv->add($s),
$inv->subtract($s),
];
$this->beta = $betas[0]->compare($betas[1]) < 0 ? $betas[0] : $betas[1];
//echo strtoupper($this->beta->toHex(true)) . "\n"; exit;
}
if (!isset($this->basis)) {
$factory = new PrimeField($this->order);
$tempOne = $factory->newInteger($one);
$tempTwo = $factory->newInteger($two);
$tempThree = $factory->newInteger(new BigInteger(3));
$inv = $tempOne->divide($tempTwo)->negate();
$s = $tempThree->negate()->squareRoot()->multiply($inv);
$lambdas = [
$inv->add($s),
$inv->subtract($s),
];
$lhs = $this->multiplyPoint($this->p, $lambdas[0])[0];
$rhs = $this->p[0]->multiply($this->beta);
$lambda = $lhs->equals($rhs) ? $lambdas[0] : $lambdas[1];
$this->basis = static::extendedGCD($lambda->toBigInteger(), $this->order);
///*
foreach ($this->basis as $basis) {
echo strtoupper($basis['a']->toHex(true)) . "\n";
echo strtoupper($basis['b']->toHex(true)) . "\n\n";
}
exit;
//*/
}
$npoints = $nscalars = [];
for ($i = 0; $i < count($points); $i++) {
$p = $points[$i];
$k = $scalars[$i]->toBigInteger();
// begin split
[$v1, $v2] = $this->basis;
$c1 = $v2['b']->multiply($k);
[$c1, $r] = $c1->divide($this->order);
if ($this->order->compare($r->multiply($two)) <= 0) {
$c1 = $c1->add($one);
}
$c2 = $v1['b']->negate()->multiply($k);
[$c2, $r] = $c2->divide($this->order);
if ($this->order->compare($r->multiply($two)) <= 0) {
$c2 = $c2->add($one);
}
$p1 = $c1->multiply($v1['a']);
$p2 = $c2->multiply($v2['a']);
$q1 = $c1->multiply($v1['b']);
$q2 = $c2->multiply($v2['b']);
$k1 = $k->subtract($p1)->subtract($p2);
$k2 = $q1->add($q2)->negate();
// end split
$beta = [
$p[0]->multiply($this->beta),
$p[1],
clone $this->one,
];
if (isset($p['naf'])) {
$beta['naf'] = array_map(function ($p) {
return [
$p[0]->multiply($this->beta),
$p[1],
clone $this->one,
];
}, $p['naf']);
$beta['nafwidth'] = $p['nafwidth'];
}
if ($k1->isNegative()) {
$k1 = $k1->negate();
$p = $this->negatePoint($p);
}
if ($k2->isNegative()) {
$k2 = $k2->negate();
$beta = $this->negatePoint($beta);
}
$pos = 2 * $i;
$npoints[$pos] = $p;
$nscalars[$pos] = $this->factory->newInteger($k1);
$pos++;
$npoints[$pos] = $beta;
$nscalars[$pos] = $this->factory->newInteger($k2);
}
return parent::multiplyAddPoints($npoints, $nscalars);
}
/**
* Returns the numerator and denominator of the slope
*
* @return FiniteField[]
*/
protected function doublePointHelper(array $p): array
{
$numerator = $this->three->multiply($p[0])->multiply($p[0]);
$denominator = $this->two->multiply($p[1]);
return [$numerator, $denominator];
}
/**
* Doubles a jacobian coordinate on the curve
*
* See http://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-0.html#doubling-dbl-2009-l
*
* @return FiniteField[]
*/
protected function jacobianDoublePoint(array $p): array
{
[$x1, $y1, $z1] = $p;
$a = $x1->multiply($x1);
$b = $y1->multiply($y1);
$c = $b->multiply($b);
$d = $x1->add($b);
$d = $d->multiply($d)->subtract($a)->subtract($c)->multiply($this->two);
$e = $this->three->multiply($a);
$f = $e->multiply($e);
$x3 = $f->subtract($this->two->multiply($d));
$y3 = $e->multiply($d->subtract($x3))->subtract(
$this->eight->multiply($c)
);
$z3 = $this->two->multiply($y1)->multiply($z1);
return [$x3, $y3, $z3];
}
/**
* Doubles a "fresh" jacobian coordinate on the curve
*
* See http://hyperelliptic.org/EFD/g1p/auto-shortw-jacobian-0.html#doubling-mdbl-2007-bl
*
* @return FiniteField[]
*/
protected function jacobianDoublePointMixed(array $p): array
{
[$x1, $y1] = $p;
$xx = $x1->multiply($x1);
$yy = $y1->multiply($y1);
$yyyy = $yy->multiply($yy);
$s = $x1->add($yy);
$s = $s->multiply($s)->subtract($xx)->subtract($yyyy)->multiply($this->two);
$m = $this->three->multiply($xx);
$t = $m->multiply($m)->subtract($this->two->multiply($s));
$x3 = $t;
$y3 = $s->subtract($t);
$y3 = $m->multiply($y3)->subtract($this->eight->multiply($yyyy));
$z3 = $this->two->multiply($y1);
return [$x3, $y3, $z3];
}
/**
* Tests whether or not the x / y values satisfy the equation
*
* @return boolean
*/
public function verifyPoint(array $p): bool
{
[$x, $y] = $p;
$lhs = $y->multiply($y);
$temp = $x->multiply($x)->multiply($x);
$rhs = $temp->add($this->b);
return $lhs->equals($rhs);
}
/**
* Calculates the parameters needed from the Euclidean algorithm as discussed at
* http://diamond.boisestate.edu/~liljanab/MATH308/GuideToECC.pdf#page=148
*
* @return BigInteger[]
*/
protected static function extendedGCD(BigInteger $u, BigInteger $v): array
{
$one = new BigInteger(1);
$zero = new BigInteger();
$a = clone $one;
$b = clone $zero;
$c = clone $zero;
$d = clone $one;
$stop = $v->bitwise_rightShift($v->getLength() >> 1);
$a1 = clone $zero;
$b1 = clone $zero;
$a2 = clone $zero;
$b2 = clone $zero;
$postGreatestIndex = 0;
while (!$v->equals($zero)) {
[$q] = $u->divide($v);
$temp = $u;
$u = $v;
$v = $temp->subtract($v->multiply($q));
$temp = $a;
$a = $c;
$c = $temp->subtract($a->multiply($q));
$temp = $b;
$b = $d;
$d = $temp->subtract($b->multiply($q));
if ($v->compare($stop) > 0) {
$a0 = $v;
$b0 = $c;
} else {
$postGreatestIndex++;
}
if ($postGreatestIndex == 1) {
$a1 = $v;
$b1 = $c->negate();
}
if ($postGreatestIndex == 2) {
$rhs = $a0->multiply($a0)->add($b0->multiply($b0));
$lhs = $v->multiply($v)->add($b->multiply($b));
if ($lhs->compare($rhs) <= 0) {
$a2 = $a0;
$b2 = $b0->negate();
} else {
$a2 = $v;
$b2 = $c->negate();
}
break;
}
}
return [
['a' => $a1, 'b' => $b1],
['a' => $a2, 'b' => $b2],
];
}
}

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<?php
/**
* Curves over y^2 = x^3 + a*x + x
*
* Technically, a Montgomery curve has a coefficient for y^2 but for Curve25519 and Curve448 that
* coefficient is 1.
*
* Curve25519 and Curve448 do not make use of the y coordinate, which makes it unsuitable for use
* with ECDSA / EdDSA. A few other differences between Curve25519 and Ed25519 are discussed at
* https://crypto.stackexchange.com/a/43058/4520
*
* More info:
*
* https://en.wikipedia.org/wiki/Montgomery_curve
*
* PHP version 5 and 7
*
* @author Jim Wigginton <terrafrost@php.net>
* @copyright 2019 Jim Wigginton
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @link http://pear.php.net/package/Math_BigInteger
*/
declare(strict_types=1);
namespace phpseclib3\Crypt\EC\BaseCurves;
use phpseclib3\Crypt\EC\Curves\Curve25519;
use phpseclib3\Exception\RuntimeException;
use phpseclib3\Exception\UnexpectedValueException;
use phpseclib3\Math\BigInteger;
use phpseclib3\Math\PrimeField;
use phpseclib3\Math\PrimeField\Integer as PrimeInteger;
/**
* Curves over y^2 = x^3 + a*x + x
*
* @author Jim Wigginton <terrafrost@php.net>
*/
class Montgomery extends Base
{
/**
* Prime Field Integer factory
*
* @var PrimeField
*/
protected $factory;
/**
* Cofficient for x
*
* @var object
*/
protected $a;
/**
* Constant used for point doubling
*
* @var object
*/
protected $a24;
/**
* The Number Zero
*
* @var object
*/
protected $zero;
/**
* The Number One
*
* @var object
*/
protected $one;
/**
* Base Point
*
* @var object
*/
protected $p;
/**
* The modulo
*
* @var BigInteger
*/
protected $modulo;
/**
* The Order
*
* @var BigInteger
*/
protected $order;
/**
* Sets the modulo
*/
public function setModulo(BigInteger $modulo): void
{
$this->modulo = $modulo;
$this->factory = new PrimeField($modulo);
$this->zero = $this->factory->newInteger(new BigInteger());
$this->one = $this->factory->newInteger(new BigInteger(1));
}
/**
* Set coefficients a
*/
public function setCoefficients(BigInteger $a): void
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
$this->a = $this->factory->newInteger($a);
$two = $this->factory->newInteger(new BigInteger(2));
$four = $this->factory->newInteger(new BigInteger(4));
$this->a24 = $this->a->subtract($two)->divide($four);
}
/**
* Set x and y coordinates for the base point
*
* @param BigInteger|PrimeInteger $x
* @param BigInteger|PrimeInteger $y
* @return PrimeInteger[]
*/
public function setBasePoint($x, $y): array
{
switch (true) {
case !$x instanceof BigInteger && !$x instanceof PrimeInteger:
throw new UnexpectedValueException('Argument 1 passed to Prime::setBasePoint() must be an instance of either BigInteger or PrimeField\Integer');
case !$y instanceof BigInteger && !$y instanceof PrimeInteger:
throw new UnexpectedValueException('Argument 2 passed to Prime::setBasePoint() must be an instance of either BigInteger or PrimeField\Integer');
}
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
$this->p = [
$x instanceof BigInteger ? $this->factory->newInteger($x) : $x,
$y instanceof BigInteger ? $this->factory->newInteger($y) : $y,
];
}
/**
* Retrieve the base point as an array
*
* @return array
*/
public function getBasePoint()
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
/*
if (!isset($this->p)) {
throw new \phpseclib3\Exception\RuntimeException('setBasePoint needs to be called before this method');
}
*/
return $this->p;
}
/**
* Doubles and adds a point on a curve
*
* See https://tools.ietf.org/html/draft-ietf-tls-curve25519-01#appendix-A.1.3
*
* @return FiniteField[][]
*/
private function doubleAndAddPoint(array $p, array $q, PrimeInteger $x1): array
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
if (!count($p) || !count($q)) {
return [];
}
if (!isset($p[1])) {
throw new RuntimeException('Affine coordinates need to be manually converted to XZ coordinates');
}
[$x2, $z2] = $p;
[$x3, $z3] = $q;
$a = $x2->add($z2);
$aa = $a->multiply($a);
$b = $x2->subtract($z2);
$bb = $b->multiply($b);
$e = $aa->subtract($bb);
$c = $x3->add($z3);
$d = $x3->subtract($z3);
$da = $d->multiply($a);
$cb = $c->multiply($b);
$temp = $da->add($cb);
$x5 = $temp->multiply($temp);
$temp = $da->subtract($cb);
$z5 = $x1->multiply($temp->multiply($temp));
$x4 = $aa->multiply($bb);
$temp = static::class == Curve25519::class ? $bb : $aa;
$z4 = $e->multiply($temp->add($this->a24->multiply($e)));
return [
[$x4, $z4],
[$x5, $z5],
];
}
/**
* Multiply a point on the curve by a scalar
*
* Uses the montgomery ladder technique as described here:
*
* https://en.wikipedia.org/wiki/Elliptic_curve_point_multiplication#Montgomery_ladder
* https://github.com/phpecc/phpecc/issues/16#issuecomment-59176772
*/
public function multiplyPoint(array $p, BigInteger $d): array
{
$p1 = [$this->one, $this->zero];
$alreadyInternal = isset($x[1]);
$p2 = $this->convertToInternal($p);
$x = $p[0];
$b = $d->toBits();
$b = str_pad($b, 256, '0', STR_PAD_LEFT);
for ($i = 0; $i < strlen($b); $i++) {
$b_i = (int) $b[$i];
if ($b_i) {
[$p2, $p1] = $this->doubleAndAddPoint($p2, $p1, $x);
} else {
[$p1, $p2] = $this->doubleAndAddPoint($p1, $p2, $x);
}
}
return $alreadyInternal ? $p1 : $this->convertToAffine($p1);
}
/**
* Converts an affine point to an XZ coordinate
*
* From https://hyperelliptic.org/EFD/g1p/auto-montgom-xz.html
*
* XZ coordinates represent x y as X Z satsfying the following equations:
*
* x=X/Z
*
* @return PrimeInteger[]
*/
public function convertToInternal(array $p): array
{
if (empty($p)) {
return [clone $this->zero, clone $this->one];
}
if (isset($p[1])) {
return $p;
}
$p[1] = clone $this->one;
return $p;
}
/**
* Returns the affine point
*
* @return PrimeInteger[]
*/
public function convertToAffine(array $p): array
{
if (!isset($p[1])) {
return $p;
}
[$x, $z] = $p;
return [$x->divide($z)];
}
}

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<?php
/**
* Curves over y^2 = x^3 + a*x + b
*
* These are curves used in SEC 2 over prime fields: http://www.secg.org/SEC2-Ver-1.0.pdf
* The curve is a weierstrass curve with a[1], a[3] and a[2] set to 0.
*
* Uses Jacobian Coordinates for speed if able:
*
* https://en.wikipedia.org/wiki/Jacobian_curve
* https://en.wikibooks.org/wiki/Cryptography/Prime_Curve/Jacobian_Coordinates
*
* PHP version 5 and 7
*
* @author Jim Wigginton <terrafrost@php.net>
* @copyright 2017 Jim Wigginton
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @link http://pear.php.net/package/Math_BigInteger
*/
declare(strict_types=1);
namespace phpseclib3\Crypt\EC\BaseCurves;
use phpseclib3\Common\Functions\Strings;
use phpseclib3\Exception\RuntimeException;
use phpseclib3\Exception\UnexpectedValueException;
use phpseclib3\Math\BigInteger;
use phpseclib3\Math\Common\FiniteField\Integer;
use phpseclib3\Math\PrimeField;
use phpseclib3\Math\PrimeField\Integer as PrimeInteger;
use phpseclib3\Math\PrimeFields;
/**
* Curves over y^2 = x^3 + a*x + b
*
* @author Jim Wigginton <terrafrost@php.net>
*/
class Prime extends Base
{
/**
* Prime Field Integer factory
*
* @var PrimeFields
*/
protected $factory;
/**
* Cofficient for x^1
*
* @var object
*/
protected $a;
/**
* Cofficient for x^0
*
* @var object
*/
protected $b;
/**
* Base Point
*
* @var object
*/
protected $p;
/**
* The number one over the specified finite field
*
* @var object
*/
protected $one;
/**
* The number two over the specified finite field
*
* @var object
*/
protected $two;
/**
* The number three over the specified finite field
*
* @var object
*/
protected $three;
/**
* The number four over the specified finite field
*
* @var object
*/
protected $four;
/**
* The number eight over the specified finite field
*
* @var object
*/
protected $eight;
/**
* The modulo
*
* @var BigInteger
*/
protected $modulo;
/**
* The Order
*
* @var BigInteger
*/
protected $order;
/**
* Sets the modulo
*/
public function setModulo(BigInteger $modulo): void
{
$this->modulo = $modulo;
$this->factory = new PrimeField($modulo);
$this->two = $this->factory->newInteger(new BigInteger(2));
$this->three = $this->factory->newInteger(new BigInteger(3));
// used by jacobian coordinates
$this->one = $this->factory->newInteger(new BigInteger(1));
$this->four = $this->factory->newInteger(new BigInteger(4));
$this->eight = $this->factory->newInteger(new BigInteger(8));
}
/**
* Set coefficients a and b
*/
public function setCoefficients(BigInteger $a, BigInteger $b): void
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
$this->a = $this->factory->newInteger($a);
$this->b = $this->factory->newInteger($b);
}
/**
* Set x and y coordinates for the base point
*
* @param BigInteger|PrimeInteger $x
* @param BigInteger|PrimeInteger $y
*/
public function setBasePoint($x, $y): void
{
switch (true) {
case !$x instanceof BigInteger && !$x instanceof PrimeInteger:
throw new UnexpectedValueException('Argument 1 passed to Prime::setBasePoint() must be an instance of either BigInteger or PrimeField\Integer');
case !$y instanceof BigInteger && !$y instanceof PrimeInteger:
throw new UnexpectedValueException('Argument 2 passed to Prime::setBasePoint() must be an instance of either BigInteger or PrimeField\Integer');
}
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
$this->p = [
$x instanceof BigInteger ? $this->factory->newInteger($x) : $x,
$y instanceof BigInteger ? $this->factory->newInteger($y) : $y,
];
}
/**
* Retrieve the base point as an array
*
* @return array
*/
public function getBasePoint()
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
/*
if (!isset($this->p)) {
throw new \phpseclib3\Exception\RuntimeException('setBasePoint needs to be called before this method');
}
*/
return $this->p;
}
/**
* Adds two "fresh" jacobian form on the curve
*
* @return FiniteField[]
*/
protected function jacobianAddPointMixedXY(array $p, array $q): array
{
[$u1, $s1] = $p;
[$u2, $s2] = $q;
if ($u1->equals($u2)) {
if (!$s1->equals($s2)) {
return [];
} else {
return $this->doublePoint($p);
}
}
$h = $u2->subtract($u1);
$r = $s2->subtract($s1);
$h2 = $h->multiply($h);
$h3 = $h2->multiply($h);
$v = $u1->multiply($h2);
$x3 = $r->multiply($r)->subtract($h3)->subtract($v->multiply($this->two));
$y3 = $r->multiply(
$v->subtract($x3)
)->subtract(
$s1->multiply($h3)
);
return [$x3, $y3, $h];
}
/**
* Adds one "fresh" jacobian form on the curve
*
* The second parameter should be the "fresh" one
*
* @return FiniteField[]
*/
protected function jacobianAddPointMixedX(array $p, array $q): array
{
[$u1, $s1, $z1] = $p;
[$x2, $y2] = $q;
$z12 = $z1->multiply($z1);
$u2 = $x2->multiply($z12);
$s2 = $y2->multiply($z12->multiply($z1));
if ($u1->equals($u2)) {
if (!$s1->equals($s2)) {
return [];
} else {
return $this->doublePoint($p);
}
}
$h = $u2->subtract($u1);
$r = $s2->subtract($s1);
$h2 = $h->multiply($h);
$h3 = $h2->multiply($h);
$v = $u1->multiply($h2);
$x3 = $r->multiply($r)->subtract($h3)->subtract($v->multiply($this->two));
$y3 = $r->multiply(
$v->subtract($x3)
)->subtract(
$s1->multiply($h3)
);
$z3 = $h->multiply($z1);
return [$x3, $y3, $z3];
}
/**
* Adds two jacobian coordinates on the curve
*
* @return FiniteField[]
*/
protected function jacobianAddPoint(array $p, array $q): array
{
[$x1, $y1, $z1] = $p;
[$x2, $y2, $z2] = $q;
$z12 = $z1->multiply($z1);
$z22 = $z2->multiply($z2);
$u1 = $x1->multiply($z22);
$u2 = $x2->multiply($z12);
$s1 = $y1->multiply($z22->multiply($z2));
$s2 = $y2->multiply($z12->multiply($z1));
if ($u1->equals($u2)) {
if (!$s1->equals($s2)) {
return [];
} else {
return $this->doublePoint($p);
}
}
$h = $u2->subtract($u1);
$r = $s2->subtract($s1);
$h2 = $h->multiply($h);
$h3 = $h2->multiply($h);
$v = $u1->multiply($h2);
$x3 = $r->multiply($r)->subtract($h3)->subtract($v->multiply($this->two));
$y3 = $r->multiply(
$v->subtract($x3)
)->subtract(
$s1->multiply($h3)
);
$z3 = $h->multiply($z1)->multiply($z2);
return [$x3, $y3, $z3];
}
/**
* Adds two points on the curve
*
* @return FiniteField[]
*/
public function addPoint(array $p, array $q): array
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
if (!count($p) || !count($q)) {
if (count($q)) {
return $q;
}
if (count($p)) {
return $p;
}
return [];
}
// use jacobian coordinates
if (isset($p[2]) && isset($q[2])) {
if (isset($p['fresh']) && isset($q['fresh'])) {
return $this->jacobianAddPointMixedXY($p, $q);
}
if (isset($p['fresh'])) {
return $this->jacobianAddPointMixedX($q, $p);
}
if (isset($q['fresh'])) {
return $this->jacobianAddPointMixedX($p, $q);
}
return $this->jacobianAddPoint($p, $q);
}
if (isset($p[2]) || isset($q[2])) {
throw new RuntimeException('Affine coordinates need to be manually converted to Jacobi coordinates or vice versa');
}
if ($p[0]->equals($q[0])) {
if (!$p[1]->equals($q[1])) {
return [];
} else { // eg. doublePoint
[$numerator, $denominator] = $this->doublePointHelper($p);
}
} else {
$numerator = $q[1]->subtract($p[1]);
$denominator = $q[0]->subtract($p[0]);
}
$slope = $numerator->divide($denominator);
$x = $slope->multiply($slope)->subtract($p[0])->subtract($q[0]);
$y = $slope->multiply($p[0]->subtract($x))->subtract($p[1]);
return [$x, $y];
}
/**
* Returns the numerator and denominator of the slope
*
* @return FiniteField[]
*/
protected function doublePointHelper(array $p): array
{
$numerator = $this->three->multiply($p[0])->multiply($p[0])->add($this->a);
$denominator = $this->two->multiply($p[1]);
return [$numerator, $denominator];
}
/**
* Doubles a jacobian coordinate on the curve
*
* @return FiniteField[]
*/
protected function jacobianDoublePoint(array $p): array
{
[$x, $y, $z] = $p;
$x2 = $x->multiply($x);
$y2 = $y->multiply($y);
$z2 = $z->multiply($z);
$s = $this->four->multiply($x)->multiply($y2);
$m1 = $this->three->multiply($x2);
$m2 = $this->a->multiply($z2->multiply($z2));
$m = $m1->add($m2);
$x1 = $m->multiply($m)->subtract($this->two->multiply($s));
$y1 = $m->multiply($s->subtract($x1))->subtract(
$this->eight->multiply($y2->multiply($y2))
);
$z1 = $this->two->multiply($y)->multiply($z);
return [$x1, $y1, $z1];
}
/**
* Doubles a "fresh" jacobian coordinate on the curve
*
* @return FiniteField[]
*/
protected function jacobianDoublePointMixed(array $p): array
{
[$x, $y] = $p;
$x2 = $x->multiply($x);
$y2 = $y->multiply($y);
$s = $this->four->multiply($x)->multiply($y2);
$m1 = $this->three->multiply($x2);
$m = $m1->add($this->a);
$x1 = $m->multiply($m)->subtract($this->two->multiply($s));
$y1 = $m->multiply($s->subtract($x1))->subtract(
$this->eight->multiply($y2->multiply($y2))
);
$z1 = $this->two->multiply($y);
return [$x1, $y1, $z1];
}
/**
* Doubles a point on a curve
*
* @return FiniteField[]
*/
public function doublePoint(array $p): array
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
if (!count($p)) {
return [];
}
// use jacobian coordinates
if (isset($p[2])) {
if (isset($p['fresh'])) {
return $this->jacobianDoublePointMixed($p);
}
return $this->jacobianDoublePoint($p);
}
[$numerator, $denominator] = $this->doublePointHelper($p);
$slope = $numerator->divide($denominator);
$x = $slope->multiply($slope)->subtract($p[0])->subtract($p[0]);
$y = $slope->multiply($p[0]->subtract($x))->subtract($p[1]);
return [$x, $y];
}
/**
* Returns the X coordinate and the derived Y coordinate
*/
public function derivePoint($m): array
{
$y = ord(Strings::shift($m));
$x = new BigInteger($m, 256);
$xp = $this->convertInteger($x);
switch ($y) {
case 2:
$ypn = false;
break;
case 3:
$ypn = true;
break;
default:
throw new RuntimeException('Coordinate not in recognized format');
}
$temp = $xp->multiply($this->a);
$temp = $xp->multiply($xp)->multiply($xp)->add($temp);
$temp = $temp->add($this->b);
$b = $temp->squareRoot();
if (!$b) {
throw new RuntimeException('Unable to derive Y coordinate');
}
$bn = $b->isOdd();
$yp = $ypn == $bn ? $b : $b->negate();
return [$xp, $yp];
}
/**
* Tests whether or not the x / y values satisfy the equation
*
* @return boolean
*/
public function verifyPoint(array $p): bool
{
[$x, $y] = $p;
$lhs = $y->multiply($y);
$temp = $x->multiply($this->a);
$temp = $x->multiply($x)->multiply($x)->add($temp);
$rhs = $temp->add($this->b);
return $lhs->equals($rhs);
}
/**
* Returns the modulo
*/
public function getModulo(): BigInteger
{
return $this->modulo;
}
/**
* Returns the a coefficient
*
* @return PrimeInteger
*/
public function getA()
{
return $this->a;
}
/**
* Returns the a coefficient
*
* @return PrimeInteger
*/
public function getB()
{
return $this->b;
}
/**
* Multiply and Add Points
*
* Adapted from:
* https://github.com/indutny/elliptic/blob/725bd91/lib/elliptic/curve/base.js#L125
*
* @return int[]
*/
public function multiplyAddPoints(array $points, array $scalars): array
{
$length = count($points);
foreach ($points as &$point) {
$point = $this->convertToInternal($point);
}
$wnd = [$this->getNAFPoints($points[0], 7)];
$wndWidth = [$points[0]['nafwidth'] ?? 7];
for ($i = 1; $i < $length; $i++) {
$wnd[] = $this->getNAFPoints($points[$i], 1);
$wndWidth[] = $points[$i]['nafwidth'] ?? 1;
}
$naf = [];
// comb all window NAFs
$max = 0;
for ($i = $length - 1; $i >= 1; $i -= 2) {
$a = $i - 1;
$b = $i;
if ($wndWidth[$a] != 1 || $wndWidth[$b] != 1) {
$naf[$a] = $scalars[$a]->getNAF($wndWidth[$a]);
$naf[$b] = $scalars[$b]->getNAF($wndWidth[$b]);
$max = max(count($naf[$a]), count($naf[$b]), $max);
continue;
}
$comb = [
$points[$a], // 1
null, // 3
null, // 5
$points[$b], // 7
];
$comb[1] = $this->addPoint($points[$a], $points[$b]);
$comb[2] = $this->addPoint($points[$a], $this->negatePoint($points[$b]));
$index = [
-3, /* -1 -1 */
-1, /* -1 0 */
-5, /* -1 1 */
-7, /* 0 -1 */
0, /* 0 -1 */
7, /* 0 1 */
5, /* 1 -1 */
1, /* 1 0 */
3, /* 1 1 */
];
$jsf = self::getJSFPoints($scalars[$a], $scalars[$b]);
$max = max(count($jsf[0]), $max);
if ($max > 0) {
$naf[$a] = array_fill(0, $max, 0);
$naf[$b] = array_fill(0, $max, 0);
} else {
$naf[$a] = [];
$naf[$b] = [];
}
for ($j = 0; $j < $max; $j++) {
$ja = $jsf[0][$j] ?? 0;
$jb = $jsf[1][$j] ?? 0;
$naf[$a][$j] = $index[3 * ($ja + 1) + $jb + 1];
$naf[$b][$j] = 0;
$wnd[$a] = $comb;
}
}
$acc = [];
$temp = [0, 0, 0, 0];
for ($i = $max; $i >= 0; $i--) {
$k = 0;
while ($i >= 0) {
$zero = true;
for ($j = 0; $j < $length; $j++) {
$temp[$j] = $naf[$j][$i] ?? 0;
if ($temp[$j] != 0) {
$zero = false;
}
}
if (!$zero) {
break;
}
$k++;
$i--;
}
if ($i >= 0) {
$k++;
}
while ($k--) {
$acc = $this->doublePoint($acc);
}
if ($i < 0) {
break;
}
for ($j = 0; $j < $length; $j++) {
$z = $temp[$j];
$p = null;
if ($z == 0) {
continue;
}
$p = $z > 0 ?
$wnd[$j][($z - 1) >> 1] :
$this->negatePoint($wnd[$j][(-$z - 1) >> 1]);
$acc = $this->addPoint($acc, $p);
}
}
return $this->convertToAffine($acc);
}
/**
* Precomputes NAF points
*
* Adapted from:
* https://github.com/indutny/elliptic/blob/725bd91/lib/elliptic/curve/base.js#L351
*
* @return list<array>
*/
private function getNAFPoints(array $point, int $wnd): array
{
if (isset($point['naf'])) {
return $point['naf'];
}
$res = [$point];
$max = (1 << $wnd) - 1;
$dbl = $max == 1 ? null : $this->doublePoint($point);
for ($i = 1; $i < $max; $i++) {
$res[] = $this->addPoint($res[$i - 1], $dbl);
}
$point['naf'] = $res;
/*
$str = '';
foreach ($res as $re) {
$re[0] = bin2hex($re[0]->toBytes());
$re[1] = bin2hex($re[1]->toBytes());
$str.= " ['$re[0]', '$re[1]'],\r\n";
}
file_put_contents('temp.txt', $str);
exit;
*/
return $res;
}
/**
* Precomputes points in Joint Sparse Form
*
* Adapted from:
* https://github.com/indutny/elliptic/blob/725bd91/lib/elliptic/utils.js#L96
*
* @return int[]
*/
private static function getJSFPoints(Integer $k1, Integer $k2): array
{
static $three;
if (!isset($three)) {
$three = new BigInteger(3);
}
$jsf = [[], []];
$k1 = $k1->toBigInteger();
$k2 = $k2->toBigInteger();
$d1 = 0;
$d2 = 0;
while ($k1->compare(new BigInteger(-$d1)) > 0 || $k2->compare(new BigInteger(-$d2)) > 0) {
// first phase
$m14 = $k1->testBit(0) + 2 * $k1->testBit(1);
$m14 += $d1;
$m14 &= 3;
$m24 = $k2->testBit(0) + 2 * $k2->testBit(1);
$m24 += $d2;
$m24 &= 3;
if ($m14 == 3) {
$m14 = -1;
}
if ($m24 == 3) {
$m24 = -1;
}
$u1 = 0;
if ($m14 & 1) { // if $m14 is odd
$m8 = $k1->testBit(0) + 2 * $k1->testBit(1) + 4 * $k1->testBit(2);
$m8 += $d1;
$m8 &= 7;
$u1 = ($m8 == 3 || $m8 == 5) && $m24 == 2 ? -$m14 : $m14;
}
$jsf[0][] = $u1;
$u2 = 0;
if ($m24 & 1) { // if $m24 is odd
$m8 = $k2->testBit(0) + 2 * $k2->testBit(1) + 4 * $k2->testBit(2);
$m8 += $d2;
$m8 &= 7;
$u2 = ($m8 == 3 || $m8 == 5) && $m14 == 2 ? -$m24 : $m24;
}
$jsf[1][] = $u2;
// second phase
if (2 * $d1 == $u1 + 1) {
$d1 = 1 - $d1;
}
if (2 * $d2 == $u2 + 1) {
$d2 = 1 - $d2;
}
$k1 = $k1->bitwise_rightShift(1);
$k2 = $k2->bitwise_rightShift(1);
}
return $jsf;
}
/**
* Returns the affine point
*
* A Jacobian Coordinate is of the form (x, y, z).
* To convert a Jacobian Coordinate to an Affine Point
* you do (x / z^2, y / z^3)
*
* @return PrimeInteger[]
*/
public function convertToAffine(array $p): array
{
if (!isset($p[2])) {
return $p;
}
[$x, $y, $z] = $p;
$z = $this->one->divide($z);
$z2 = $z->multiply($z);
return [
$x->multiply($z2),
$y->multiply($z2)->multiply($z),
];
}
/**
* Converts an affine point to a jacobian coordinate
*
* @return PrimeInteger[]
*/
public function convertToInternal(array $p): array
{
if (isset($p[2])) {
return $p;
}
$p[2] = clone $this->one;
$p['fresh'] = true;
return $p;
}
}

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@@ -0,0 +1,215 @@
<?php
/**
* Curves over a*x^2 + y^2 = 1 + d*x^2*y^2
*
* http://www.secg.org/SEC2-Ver-1.0.pdf provides for curves with custom parameters.
* ie. the coefficients can be arbitrary set through specially formatted keys, etc.
* As such, Prime.php is built very generically and it's not able to take full
* advantage of curves with 0 coefficients to produce simplified point doubling,
* point addition. Twisted Edwards curves, in contrast, do not have a way, currently,
* to customize them. As such, we can omit the super generic stuff from this class
* and let the named curves (Ed25519 and Ed448) define their own custom tailored
* point addition and point doubling methods.
*
* More info:
*
* https://en.wikipedia.org/wiki/Twisted_Edwards_curve
*
* PHP version 5 and 7
*
* @author Jim Wigginton <terrafrost@php.net>
* @copyright 2017 Jim Wigginton
* @license http://www.opensource.org/licenses/mit-license.html MIT License
* @link http://pear.php.net/package/Math_BigInteger
*/
declare(strict_types=1);
namespace phpseclib3\Crypt\EC\BaseCurves;
use phpseclib3\Exception\RuntimeException;
use phpseclib3\Exception\UnexpectedValueException;
use phpseclib3\Math\BigInteger;
use phpseclib3\Math\PrimeField;
use phpseclib3\Math\PrimeField\Integer as PrimeInteger;
/**
* Curves over a*x^2 + y^2 = 1 + d*x^2*y^2
*
* @author Jim Wigginton <terrafrost@php.net>
*/
class TwistedEdwards extends Base
{
/**
* The modulo
*
* @var BigInteger
*/
protected $modulo;
/**
* Cofficient for x^2
*
* @var object
*/
protected $a;
/**
* Cofficient for x^2*y^2
*
* @var object
*/
protected $d;
/**
* Base Point
*
* @var object[]
*/
protected $p;
/**
* The number zero over the specified finite field
*
* @var object
*/
protected $zero;
/**
* The number one over the specified finite field
*
* @var object
*/
protected $one;
/**
* The number two over the specified finite field
*
* @var object
*/
protected $two;
/**
* Sets the modulo
*/
public function setModulo(BigInteger $modulo): void
{
$this->modulo = $modulo;
$this->factory = new PrimeField($modulo);
$this->zero = $this->factory->newInteger(new BigInteger(0));
$this->one = $this->factory->newInteger(new BigInteger(1));
$this->two = $this->factory->newInteger(new BigInteger(2));
}
/**
* Set coefficients a and b
*/
public function setCoefficients(BigInteger $a, BigInteger $d): void
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
$this->a = $this->factory->newInteger($a);
$this->d = $this->factory->newInteger($d);
}
/**
* Set x and y coordinates for the base point
*/
public function setBasePoint($x, $y): void
{
switch (true) {
case !$x instanceof BigInteger && !$x instanceof PrimeInteger:
throw new UnexpectedValueException('Argument 1 passed to Prime::setBasePoint() must be an instance of either BigInteger or PrimeField\Integer');
case !$y instanceof BigInteger && !$y instanceof PrimeInteger:
throw new UnexpectedValueException('Argument 2 passed to Prime::setBasePoint() must be an instance of either BigInteger or PrimeField\Integer');
}
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
$this->p = [
$x instanceof BigInteger ? $this->factory->newInteger($x) : $x,
$y instanceof BigInteger ? $this->factory->newInteger($y) : $y,
];
}
/**
* Returns the a coefficient
*
* @return PrimeInteger
*/
public function getA()
{
return $this->a;
}
/**
* Returns the a coefficient
*
* @return PrimeInteger
*/
public function getD()
{
return $this->d;
}
/**
* Retrieve the base point as an array
*/
public function getBasePoint(): array
{
if (!isset($this->factory)) {
throw new RuntimeException('setModulo needs to be called before this method');
}
/*
if (!isset($this->p)) {
throw new \phpseclib3\Exception\RuntimeException('setBasePoint needs to be called before this method');
}
*/
return $this->p;
}
/**
* Returns the affine point
*
* @return PrimeInteger[]
*/
public function convertToAffine(array $p): array
{
if (!isset($p[2])) {
return $p;
}
[$x, $y, $z] = $p;
$z = $this->one->divide($z);
return [
$x->multiply($z),
$y->multiply($z),
];
}
/**
* Returns the modulo
*/
public function getModulo(): BigInteger
{
return $this->modulo;
}
/**
* Tests whether or not the x / y values satisfy the equation
*
* @return boolean
*/
public function verifyPoint(array $p): bool
{
[$x, $y] = $p;
$x2 = $x->multiply($x);
$y2 = $y->multiply($y);
$lhs = $this->a->multiply($x2)->add($y2);
$rhs = $this->d->multiply($x2)->multiply($y2)->add($this->one);
return $lhs->equals($rhs);
}
}