Proyectos de Subversion Moodle

<?php

namespace Aws\EndpointV2\Ruleset;

use Aws\Exception\UnresolvedEndpointException;

/**

 * Provides functions and actions to be performed for endpoint evaluation.

 * This is an internal only class and is not subject to backwards-compatibility guarantees.

 *

 * @internal

 */

class RulesetStandardLibrary

{

    const IPV4_RE = '/^(?:[0-9]{1,3}\.){3}[0-9]{1,3}$/';

    const IPV6_RE = '/([0-9a-fA-F]{1,4}:){7,7}[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,7}:|

                    . ([0-9a-fA-F]{1,4}:){1,6}:[0-9a-fA-F]{1,4}|([0-9a-fA-F]{1,4}:){1,5}(:[0-9a-fA-F]

                    . {1,4}){1,2}|([0-9a-fA-F]{1,4}:){1,4}(:[0-9a-fA-F]{1,4}){1,3}|([0-9a-fA-F]{1,4}:)

                    . {1,3}(:[0-9a-fA-F]{1,4}){1,4}|([0-9a-fA-F]{1,4}:){1,2}(:[0-9a-fA-F]{1,4}){1,5}|

                    . [0-9a-fA-F]{1,4}:((:[0-9a-fA-F]{1,4}){1,6})|:((:[0-9a-fA-F]{1,4}){1,7}|:)|fe80:

                    . (:[0-9a-fA-F]{0,4}){0,4}%[0-9a-zA-Z]{1,}|::(ffff(:0{1,4}){0,1}:){0,1}((25[0-5]|(2[0-4]|

                    . 1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])|([0-9a-fA-F]

                    . {1,4}:){1,4}:((25[0-5]|(2[0-4]|1{0,1}[0-9]){0,1}[0-9])\.){3,3}(25[0-5]|(2[0-4]

                    . |1{0,1}[0-9]){0,1}[0-9])/';

    const TEMPLATE_ESCAPE_RE = '/{\{\s*(.*?)\s*\}\}/';

    const TEMPLATE_SEARCH_RE = '/\{[a-zA-Z#]+\}/';

    const TEMPLATE_PARSE_RE = '#\{((?>[^\{\}]+)|(?R))*\}#x';

    const HOST_LABEL_RE = '/^(?!-)[a-zA-Z\d-]{1,63}(?<!-)$/';

    private $partitions;

    public function __construct($partitions)

    {

        $this->partitions = $partitions;

    }

    /**

     * Determines if a value is set.

     *

     * @return boolean

     */

    public function is_set($value)

    {

        return isset($value);

    }

    /**

     * Function implementation of logical operator `not`

     *

     * @return boolean

     */

    public function not($value)

    {

        return !$value;

    }

    /**

     * Find an attribute within a value given a path string.

     *

     * @return mixed

     */

    public function getAttr($from, $path)

    {

        // Handles the case where "[<int|string]" is provided as the top-level path

        if (preg_match('/^\[(\w+)\]$/', $path, $matches)) {

            $index = is_numeric($matches[1]) ? (int) $matches[1] : $matches[1];

            return $from[$index] ?? null;

        }

        $parts = explode('.', $path);

        foreach ($parts as $part) {

            $sliceIdx = strpos($part, '[');

            if ($sliceIdx !== false) {

                if (substr($part, -1) !== ']') {

                    return null;

                }

                $slice = (int) substr($part, $sliceIdx + 1, strlen($part) - 1);

                $fromIndex = substr($part, 0, $sliceIdx);

                $from = $from[$fromIndex][$slice] ?? null;

            } else {

                $from = $from[$part];

            }

        }

        return $from;

    }

    /**

     * Computes a substring given the start index and end index. If `reverse` is

     * true, slice the string from the end instead.

     *

     * @return mixed

     */

    public function substring($input, $start, $stop, $reverse)

    {

        if (!is_string($input)) {

            throw new UnresolvedEndpointException(

                'Input passed to `substring` must be `string`.'

            );

        }

        if (preg_match('/[^\x00-\x7F]/', $input)) {

            return null;

        }

        if ($start >= $stop or strlen($input) < $stop) {

            return null;

        }

        if (!$reverse) {

            return substr($input, $start, $stop - $start);

        } else {

            $offset = strlen($input) - $stop;

            $length = $stop - $start;

            return substr($input, $offset, $length);

        }

    }

    /**

     * Evaluates two strings for equality.

     *

     * @return boolean

     */

    public function stringEquals($string1, $string2)

    {

        if (!is_string($string1) || !is_string($string2)) {

            throw new UnresolvedEndpointException(

                'Values passed to StringEquals must be `string`.'

            );

        }

        return $string1 === $string2;

    }

    /**

     * Evaluates two booleans for equality.

     *

     * @return boolean

     */

    public function booleanEquals($boolean1, $boolean2)

    {

        return

            filter_var($boolean1, FILTER_VALIDATE_BOOLEAN)

            === filter_var($boolean2, FILTER_VALIDATE_BOOLEAN);

    }

    /**

     * Percent-encodes an input string.

     *

     * @return mixed

     */

    public function uriEncode($input)

    {

        if (is_null($input)) {

            return null;

        }

        return str_replace('%7E', '~', rawurlencode($input));

    }

    /**

     * Parses URL string into components.

     *

     * @return mixed

     */

    public function parseUrl($url)

    {

        if (is_null($url)) {

            return null;

        }

        $parsed = parse_url($url);

        if ($parsed === false || !empty($parsed['query'])) {

            return null;

        } elseif (!isset($parsed['scheme'])) {

            return null;

        }

        if ($parsed['scheme'] !== 'http'

            && $parsed['scheme'] !== 'https'

        ) {

            return null;

        }

        $urlInfo = [];

        $urlInfo['scheme'] = $parsed['scheme'];

        $urlInfo['authority'] = isset($parsed['host']) ? $parsed['host'] : '';

        if (isset($parsed['port'])) {

            $urlInfo['authority'] = $urlInfo['authority'] . ":" . $parsed['port'];

        }

        $urlInfo['path'] = isset($parsed['path']) ? $parsed['path'] : '';

        $urlInfo['normalizedPath'] = !empty($parsed['path'])

            ? rtrim($urlInfo['path'] ?: '', '/' .  "/") . '/'

            : '/';

        $urlInfo['isIp'] = !isset($parsed['host']) ?

            'false' : $this->isValidIp($parsed['host']);

        return $urlInfo;

    }

    /**

     * Evaluates whether a value is a valid host label per

     * RFC 1123. If allow_subdomains is true, split on `.` and validate

     * each subdomain separately.

     *

     * @return boolean

     */

    public function isValidHostLabel($hostLabel, $allowSubDomains)

    {

        if (!isset($hostLabel)

            || (!$allowSubDomains && strpos($hostLabel, '.') != false)

        ) {

            return false;

        }

        if ($allowSubDomains) {

            foreach (explode('.', $hostLabel) as $subdomain) {

                if (!$this->validateHostLabel($subdomain)) {

                    return false;

                }

            }

            return true;

        } else {

            return $this->validateHostLabel($hostLabel);

        }

    }

    /**

     * Parse and validate string for ARN components.

     *

     * @return array|null

     */

    public function parseArn($arnString)

    {

        if (is_null($arnString)

            || substr( $arnString, 0, 3 ) !== "arn"

        ) {

            return null;

        }

        $arn = [];

        $parts = explode(':', $arnString, 6);

        if (sizeof($parts) < 6) {

            return null;

        }

        $arn['partition'] = isset($parts[1]) ? $parts[1] : null;

        $arn['service'] = isset($parts[2]) ? $parts[2] : null;

        $arn['region'] = isset($parts[3]) ? $parts[3] : null;

        $arn['accountId'] = isset($parts[4]) ? $parts[4] : null;

        $arn['resourceId'] = isset($parts[5]) ? $parts[5] : null;

        if (empty($arn['partition'])

            || empty($arn['service'])

            || empty($arn['resourceId'])

        ) {

            return null;

        }

        $resource = $arn['resourceId'];

        $arn['resourceId'] = preg_split("/[:\/]/", $resource);

        return $arn;

    }

    /**

     * Matches a region string to an AWS partition.

     *

     * @return mixed

     */

    public function partition($region)

    {

        if (!is_string($region)) {

            throw new UnresolvedEndpointException(

                'Value passed to `partition` must be `string`.'

            );

        }

        $partitions = $this->partitions;

        foreach ($partitions['partitions'] as $partition) {

            if (array_key_exists($region, $partition['regions'])

                || preg_match("/{$partition['regionRegex']}/", $region)

            ) {

                return $partition['outputs'];

            }

        }

        //return `aws` partition if no match is found.

        return $partitions['partitions'][0]['outputs'];

    }

    /**

     * Evaluates whether a value is a valid bucket name for virtual host

     * style bucket URLs.

     *

     * @return boolean

     */

    public function isVirtualHostableS3Bucket($bucketName, $allowSubdomains)

    {

        if ((is_null($bucketName)

            || (strlen($bucketName) < 3 || strlen($bucketName) > 63))

            || preg_match(self::IPV4_RE, $bucketName)

            || strtolower($bucketName) !== $bucketName

        ) {

            return false;

        }

        if ($allowSubdomains) {

            $labels = explode('.', $bucketName);

            $results = [];

            forEach($labels as $label) {

                $results[] = $this->isVirtualHostableS3Bucket($label, false);

            }

            return !in_array(false, $results);

        }

        return $this->isValidHostLabel($bucketName, false);

    }

    public function callFunction($funcCondition, &$inputParameters)

    {

        $funcArgs = [];

        forEach($funcCondition['argv'] as $arg) {

            $funcArgs[] = $this->resolveValue($arg, $inputParameters);

        }

        $funcName = str_replace('aws.', '', $funcCondition['fn']);

        if ($funcName === 'isSet') {

            $funcName = 'is_set';

        }

        $result = call_user_func_array(

            [RulesetStandardLibrary::class, $funcName],

            $funcArgs

        );

        if (isset($funcCondition['assign'])) {

            $assign = $funcCondition['assign'];

            if (isset($inputParameters[$assign])){

                throw new UnresolvedEndpointException(

                    "Assignment `{$assign}` already exists in input parameters" .

                    " or has already been assigned by an endpoint rule and cannot be overwritten."

                );

            }

            $inputParameters[$assign] = $result;

        }

        return $result;

    }

    public function resolveValue($value, $inputParameters)

    {

        //Given a value, check if it's a function, reference or template.

        //returns resolved value

        if ($this->isFunc($value)) {

            return $this->callFunction($value, $inputParameters);

        } elseif ($this->isRef($value)) {

            return isset($inputParameters[$value['ref']]) ? $inputParameters[$value['ref']] : null;

        } elseif ($this->isTemplate($value)) {

            return $this->resolveTemplateString($value, $inputParameters);

        }

        return $value;

    }

    public function isFunc($arg)

    {

        return is_array($arg) && isset($arg['fn']);

    }

    public function isRef($arg)

    {

        return is_array($arg) && isset($arg['ref']);

    }

    public function isTemplate($arg)

    {

        return is_string($arg) && !empty(preg_match(self::TEMPLATE_SEARCH_RE, $arg));

    }

    public function resolveTemplateString($value, $inputParameters)

    {

        return preg_replace_callback(

            self::TEMPLATE_PARSE_RE,

            function ($match) use ($inputParameters) {

                if (preg_match(self::TEMPLATE_ESCAPE_RE, $match[0])) {

                    return $match[1];

                }

                $notFoundMessage = 'Resolved value was null.  Please check rules and ' .

                    'input parameters and try again.';

                $parts = explode("#", $match[1]);

                if (count($parts) > 1) {

                    $resolvedValue = $inputParameters;

                    foreach($parts as $part) {

                        if (!isset($resolvedValue[$part])) {

                            throw new UnresolvedEndpointException($notFoundMessage);

                        }

                        $resolvedValue = $resolvedValue[$part];

                    }

                    return $resolvedValue;

                } else {

                    if (!isset($inputParameters[$parts[0]])) {

                        throw new UnresolvedEndpointException($notFoundMessage);

                    }

                    return $inputParameters[$parts[0]];

                }

            },

            $value

        );

    }

    private function validateHostLabel ($hostLabel)

    {

        if (empty($hostLabel) || strlen($hostLabel) > 63) {

            return false;

        }

        if (preg_match(self::HOST_LABEL_RE, $hostLabel)) {

            return true;

        }

        return false;

    }

    private function isValidIp($hostName)

    {

        $isWrapped = strpos($hostName, '[') === 0

            && strrpos($hostName, ']') === strlen($hostName) - 1;

        return preg_match(

                self::IPV4_RE,

            $hostName

        )

        //IPV6 enclosed in brackets

        || ($isWrapped && preg_match(

            self::IPV6_RE,

            $hostName

        ))

            ? 'true' : 'false';

    }

}