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<?php |
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namespace WPDesk\GatewayWPPay\Helpers; |
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final class ItnHashValidator { |
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public static function is_valid( string $encoded_transactions, callable $hash_generator ): bool { |
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$xml = self::decode_payload( $encoded_transactions ); |
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|
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if ( ! $xml instanceof \SimpleXMLElement ) { |
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return false; |
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} |
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$data = DataConverter::simplexml_to_array( $xml ); |
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if ( empty( $data ) || empty( $data['hash'] ) ) { |
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return false; |
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} |
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$received_hash = trim( (string) $data['hash'] ); |
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unset( $data['hash'] ); |
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|
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$expected_hash = $hash_generator( ArrayFlattener::flatten_array( $data ) ); |
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return is_string( $expected_hash ) && hash_equals( $expected_hash, $received_hash ); |
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} |
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private static function decode_payload( string $encoded_transactions ): ?\SimpleXMLElement { |
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$decoded_payload = base64_decode( $encoded_transactions, true ); |
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if ( $decoded_payload === false ) { |
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return null; |
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} |
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|
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$previous_state = libxml_use_internal_errors( true ); |
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$xml = simplexml_load_string( $decoded_payload ); |
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libxml_clear_errors(); |
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libxml_use_internal_errors( $previous_state ); |
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|
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return $xml instanceof \SimpleXMLElement ? $xml : null; |
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} |
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} |
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