* @copyright 2018-2026 Jim Wigginton * @license http://www.opensource.org/licenses/mit-license.html MIT License * @link https://phpseclib.com/ */ declare(strict_types=1); namespace phpseclib4\Crypt\EC\Formats\Keys; use phpseclib4\Common\Functions\Strings; use phpseclib4\Crypt\EC\BaseCurves\{ Base as BaseCurve, Montgomery as MontgomeryCurve, Prime as PrimeCurve, TwistedEdwards as TwistedEdwardsCurve }; use phpseclib4\Exception\{ BadConfigurationException, UnexpectedValueException, UnsupportedCurveException }; use phpseclib4\File\ASN1\OIDs\Curves; use phpseclib4\Math\BigInteger; use phpseclib4\Math\Common\FiniteField\Integer; /** * XML Formatted EC Key Handler * * @author Jim Wigginton * @psalm-api */ abstract class XML { use Common; /** * Default namespace */ private static string $namespace; /** * Flag for using RFC4050 syntax */ private static bool $rfc4050 = false; /** * Break a public or private key down into its constituent components * * @psalm-suppress PossiblyUnusedParam */ public static function load( #[\SensitiveParameter] string $key, #[\SensitiveParameter] ?string $password = null ): array { self::initialize_static_variables(); if (!class_exists('DOMDocument')) { throw new BadConfigurationException('The dom extension is not setup correctly on this system'); } $use_errors = libxml_use_internal_errors(true); if (substr($key, 0, 5) != '' . $key . ''; } $temp = self::isolateNamespace($key, 'http://www.w3.org/2009/xmldsig11#'); if ($temp) { $key = $temp; } $temp = self::isolateNamespace($key, 'http://www.w3.org/2001/04/xmldsig-more#'); if ($temp) { $key = $temp; } $dom = new \DOMDocument(); if (!$dom->loadXML($key)) { $e = libxml_get_last_error(); $message = 'Error loading XML - ' . $e->message; libxml_use_internal_errors($use_errors); throw new UnexpectedValueException($message, $e->code); } $xpath = new \DOMXPath($dom); libxml_use_internal_errors($use_errors); $curve = self::loadCurveByParam($xpath); $pubkey = self::query($xpath, 'publickey', 'Public Key is not present'); $QA = self::query($xpath, 'ecdsakeyvalue')->length ? self::extractPointRFC4050($xpath, $curve) : self::extractPoint("\0" . $pubkey, $curve); libxml_use_internal_errors($use_errors); return compact('curve', 'QA'); } /** * Case-insensitive xpath query */ private static function query( \DOMXPath $xpath, string $name, ?string $error = null, bool $decode = true ): \DOMNodeList|string { $query = '/'; $names = explode('/', $name); foreach ($names as $name) { $query .= "/*[translate(local-name(), 'ABCDEFGHIJKLMNOPQRSTUVWXYZ','abcdefghijklmnopqrstuvwxyz')='$name']"; } $result = $xpath->query($query); if (!isset($error)) { return $result; } if (!$result->length) { throw new UnexpectedValueException($error); } return $decode ? self::decodeValue($result->item(0)->textContent) : $result->item(0)->textContent; } /** * Finds the first element in the relevant namespace, strips the namespacing and returns the XML for that element. */ private static function isolateNamespace(string $xml, string $ns): ?string { $dom = new \DOMDocument(); if (!$dom->loadXML($xml)) { return null; } $xpath = new \DOMXPath($dom); $nodes = $xpath->query("//*[namespace::*[.='$ns'] and not(../namespace::*[.='$ns'])]"); if (!$nodes->length) { return null; } $node = $nodes->item(0); $ns_name = $node->lookupPrefix($ns); if ($ns_name) { $node->removeAttributeNS($ns, $ns_name); } return $dom->saveXML($node); } /** * Decodes the value */ private static function decodeValue(string $value): string { return Strings::base64_decode(str_replace(["\r", "\n", ' ', "\t"], '', $value)); } /** * Extract points from an XML document */ private static function extractPointRFC4050(\DOMXPath $xpath, BaseCurve $curve): array { $x = self::query($xpath, 'publickey/x'); $y = self::query($xpath, 'publickey/y'); if (!$x->length || !$x->item(0)->hasAttribute('Value')) { throw new UnexpectedValueException('Public Key / X coordinate not found'); } if (!$y->length || !$y->item(0)->hasAttribute('Value')) { throw new UnexpectedValueException('Public Key / Y coordinate not found'); } $point = [ $curve->convertInteger(new BigInteger($x->item(0)->getAttribute('Value'))), $curve->convertInteger(new BigInteger($y->item(0)->getAttribute('Value'))), ]; if (!$curve->verifyPoint($point)) { throw new UnexpectedValueException('Unable to verify that point exists on curve'); } return $point; } /** * Returns an instance of \phpseclib4\Crypt\EC\BaseCurves\Base based * on the curve parameters */ private static function loadCurveByParam(\DOMXPath $xpath): BaseCurve { $namedCurve = self::query($xpath, 'namedcurve'); if ($namedCurve->length == 1) { $oid = $namedCurve->item(0)->getAttribute('URN'); $oid = preg_replace('#[^\d.]#', '', $oid); $name = array_search($oid, Curves::OIDs); if ($name === false) { throw new UnsupportedCurveException('Curve with OID of ' . $oid . ' is not supported'); } $curve = '\phpseclib4\Crypt\EC\Curves\\' . $name; if (!class_exists($curve)) { throw new UnsupportedCurveException('Named Curve of ' . $name . ' is not supported'); } return new $curve(); } $params = self::query($xpath, 'explicitparams'); if ($params->length) { return self::loadCurveByParamRFC4050($xpath); } self::query($xpath, 'ecparameters', 'No parameters are present'); $fieldTypes = [ 'prime-field' => ['fieldid/prime/p'], 'gnb' => ['fieldid/gnb/m'], 'tnb' => ['fieldid/tnb/k'], 'pnb' => ['fieldid/pnb/k1', 'fieldid/pnb/k2', 'fieldid/pnb/k3'], 'unknown' => [], ]; foreach ($fieldTypes as $type => $queries) { foreach ($queries as $query) { $result = self::query($xpath, $query); if (!$result->length) { continue 2; } $param = preg_replace('#.*/#', '', $query); $$param = self::decodeValue($result->item(0)->textContent); } break; } $a = self::query($xpath, 'curve/a', 'A coefficient is not present'); $b = self::query($xpath, 'curve/b', 'B coefficient is not present'); $base = self::query($xpath, 'base', 'Base point is not present'); $order = self::query($xpath, 'order', 'Order is not present'); switch ($type) { case 'prime-field': $curve = new PrimeCurve(); /** @psalm-suppress UndefinedVariable $p */ $curve->setModulo(new BigInteger($p, 256)); $curve->setCoefficients( new BigInteger($a, 256), new BigInteger($b, 256) ); $point = self::extractPoint("\0" . $base, $curve); $curve->setBasePoint(...$point); $curve->setOrder(new BigInteger($order, 256)); return $curve; case 'gnb': case 'tnb': case 'pnb': default: throw new UnsupportedCurveException('Field Type of ' . $type . ' is not supported'); } } /** * Returns an instance of \phpseclib4\Crypt\EC\BaseCurves\Base based * on the curve parameters */ private static function loadCurveByParamRFC4050(\DOMXPath $xpath): BaseCurve { $fieldTypes = [ 'prime-field' => ['primefieldparamstype/p'], 'unknown' => [], ]; foreach ($fieldTypes as $type => $queries) { foreach ($queries as $query) { $result = self::query($xpath, $query); if (!$result->length) { continue 2; } $param = preg_replace('#.*/#', '', $query); $$param = $result->item(0)->textContent; } break; } $a = self::query($xpath, 'curveparamstype/a', 'A coefficient is not present', false); $b = self::query($xpath, 'curveparamstype/b', 'B coefficient is not present', false); $x = self::query($xpath, 'basepointparams/basepoint/ecpointtype/x', 'Base Point X is not present', false); $y = self::query($xpath, 'basepointparams/basepoint/ecpointtype/y', 'Base Point Y is not present', false); $order = self::query($xpath, 'order', 'Order is not present', false); switch ($type) { case 'prime-field': $curve = new PrimeCurve(); /** @psalm-suppress UndefinedVariable $p */ $p = str_replace(["\r", "\n", ' ', "\t"], '', $p); $curve->setModulo(new BigInteger($p)); $a = str_replace(["\r", "\n", ' ', "\t"], '', $a); $b = str_replace(["\r", "\n", ' ', "\t"], '', $b); $curve->setCoefficients( new BigInteger($a), new BigInteger($b) ); $x = str_replace(["\r", "\n", ' ', "\t"], '', $x); $y = str_replace(["\r", "\n", ' ', "\t"], '', $y); $curve->setBasePoint( new BigInteger($x), new BigInteger($y) ); $order = str_replace(["\r", "\n", ' ', "\t"], '', $order); $curve->setOrder(new BigInteger($order)); return $curve; default: throw new UnsupportedCurveException('Field Type of ' . $type . ' is not supported'); } } /** * Sets the namespace. dsig11 is the most common one. * * Set to null to unset. Used only for creating public keys. */ public static function setNamespace(string $namespace): void { self::$namespace = $namespace; } /** * Uses the XML syntax specified in https://tools.ietf.org/html/rfc4050 */ public static function enableRFC4050Syntax(): void { self::$rfc4050 = true; } /** * Uses the XML syntax specified in https://www.w3.org/TR/xmldsig-core/#sec-ECParameters */ public static function disableRFC4050Syntax(): void { self::$rfc4050 = false; } /** * Convert a public key to the appropriate format * * @param Integer[] $publicKey */ public static function savePublicKey(BaseCurve $curve, array $publicKey, array $options = []): string { self::initialize_static_variables(); if ($curve instanceof TwistedEdwardsCurve || $curve instanceof MontgomeryCurve) { throw new UnsupportedCurveException('TwistedEdwards and Montgomery Curves are not supported'); } if (empty(static::$namespace)) { $pre = $post = ''; } else { $pre = static::$namespace . ':'; $post = ':' . static::$namespace; } if (self::$rfc4050) { return '<' . $pre . 'ECDSAKeyValue xmlns' . $post . '="http://www.w3.org/2001/04/xmldsig-more#">' . "\r\n" . self::encodeXMLParameters($curve, $pre, $options) . "\r\n" . '<' . $pre . 'PublicKey>' . "\r\n" . '<' . $pre . 'X Value="' . $publicKey[0] . '" />' . "\r\n" . '<' . $pre . 'Y Value="' . $publicKey[1] . '" />' . "\r\n" . '' . "\r\n" . ''; } $publicKey = "\4" . $publicKey[0]->toBytes() . $publicKey[1]->toBytes(); return '<' . $pre . 'ECDSAKeyValue xmlns' . $post . '="http://www.w3.org/2009/xmldsig11#">' . "\r\n" . self::encodeXMLParameters($curve, $pre, $options) . "\r\n" . '<' . $pre . 'PublicKey>' . Strings::base64_encode($publicKey) . '' . "\r\n" . ''; } /** * Encode Parameters */ private static function encodeXMLParameters(BaseCurve $curve, string $pre, array $options = []): string { $result = self::encodeParameters($curve, true, $options); if (isset($result['namedCurve'])) { $namedCurve = '<' . $pre . 'NamedCurve URI="urn:oid:' . Curves::OIDs[$result['namedCurve']] . '" />'; return self::$rfc4050 ? '' . str_replace('URI', 'URN', $namedCurve) . '' : $namedCurve; } if (self::$rfc4050) { $xml = '<' . $pre . 'ExplicitParams>' . "\r\n" . '<' . $pre . 'FieldParams>' . "\r\n"; $temp = $result['specifiedCurve']; switch ($temp['fieldID']['fieldType']) { case 'prime-field': $xml .= '<' . $pre . 'PrimeFieldParamsType>' . "\r\n" . '<' . $pre . 'P>' . $temp['fieldID']['parameters'] . '' . "\r\n" . '' . "\r\n"; $a = $curve->getA(); $b = $curve->getB(); [$x, $y] = $curve->getBasePoint(); break; default: throw new UnsupportedCurveException('Field Type of ' . $temp['fieldID']['fieldType'] . ' is not supported'); } $xml .= '' . "\r\n" . '<' . $pre . 'CurveParamsType>' . "\r\n" . '<' . $pre . 'A>' . $a . '' . "\r\n" . '<' . $pre . 'B>' . $b . '' . "\r\n" . '' . "\r\n" . '<' . $pre . 'BasePointParams>' . "\r\n" . '<' . $pre . 'BasePoint>' . "\r\n" . '<' . $pre . 'ECPointType>' . "\r\n" . '<' . $pre . 'X>' . $x . '' . "\r\n" . '<' . $pre . 'Y>' . $y . '' . "\r\n" . '' . "\r\n" . '' . "\r\n" . '<' . $pre . 'Order>' . $curve->getOrder() . '' . "\r\n" . '' . "\r\n" . '' . "\r\n"; return $xml; } if (isset($result['specifiedCurve'])) { $xml = '<' . $pre . 'ECParameters>' . "\r\n" . '<' . $pre . 'FieldID>' . "\r\n"; $temp = $result['specifiedCurve']; switch ($temp['fieldID']['fieldType']) { case 'prime-field': $xml .= '<' . $pre . 'Prime>' . "\r\n" . '<' . $pre . 'P>' . Strings::base64_encode($temp['fieldID']['parameters']->toBytes()) . '' . "\r\n" . '' . "\r\n" ; break; default: throw new UnsupportedCurveException('Field Type of ' . $temp['fieldID']['fieldType'] . ' is not supported'); } $xml .= '' . "\r\n" . '<' . $pre . 'Curve>' . "\r\n" . '<' . $pre . 'A>' . Strings::base64_encode($temp['curve']['a']) . '' . "\r\n" . '<' . $pre . 'B>' . Strings::base64_encode($temp['curve']['b']) . '' . "\r\n" . '' . "\r\n" . '<' . $pre . 'Base>' . Strings::base64_encode($temp['base']) . '' . "\r\n" . '<' . $pre . 'Order>' . Strings::base64_encode($temp['order']) . '' . "\r\n" . ''; return $xml; } } }