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<?php |
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// Exit if accessed directly. |
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if ( ! defined( 'ABSPATH' ) ) { |
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exit; |
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} |
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|
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/** |
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* Apply security headers. |
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* |
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* This function applies several HTTP security headers to enhance site protection if the |
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* 'ns_shield_security_headers' option is enabled. The following headers are applied: |
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* - X-Frame-Options: SAMEORIGIN |
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* - X-Content-Type-Options: nosniff |
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* - Referrer-Policy: strict-origin-when-cross-origin |
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* - Permissions-Policy: geolocation=(self), microphone=() |
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* - Strict-Transport-Security: max-age=31536000 (HTTPS only) |
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* |
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* @return void |
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*/ |
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function ns_shield_security_headers_are_enabled() { |
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$security_headers_value = get_option( 'ns_shield_security_headers' ); |
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|
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return true === $security_headers_value || 1 === $security_headers_value || '1' === $security_headers_value; |
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} |
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|
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/** |
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* Apply the Referrer-Policy header once per request. |
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* |
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* @return void |
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*/ |
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function ns_shield_apply_referrer_policy() { |
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static $referrer_policy_sent = false; |
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|
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if ( $referrer_policy_sent || ! ns_shield_security_headers_are_enabled() ) { |
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return; |
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} |
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|
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header( 'Referrer-Policy: strict-origin-when-cross-origin' ); |
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$referrer_policy_sent = true; |
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} |
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|
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function ns_shield_apply_security_headers() { |
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if ( ns_shield_security_headers_are_enabled() ) { |
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header( "X-Frame-Options: SAMEORIGIN" ); |
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header( "X-Content-Type-Options: nosniff" ); |
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ns_shield_apply_referrer_policy(); |
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header( "Permissions-Policy: geolocation=(self), microphone=()" ); |
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|
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// Legacy HSTS is more restrictive and must remain the only HSTS header when active. |
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if ( is_ssl() && ! ns_shield_legacy_hsts_is_enabled() ) { |
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header( 'Strict-Transport-Security: max-age=31536000' ); |
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} |
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} |
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} |
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add_action( 'send_headers', 'ns_shield_apply_security_headers' ); |
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add_action( 'rest_pre_serve_request', 'ns_shield_apply_referrer_policy', 0 ); |
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?> |
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|
