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<?php |
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namespace Activitypub; |
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|
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/** |
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* ActivityPub Signature Class |
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* |
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* @author Matthias Pfefferle |
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*/ |
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class Signature { |
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|
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/** |
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* @param int $user_id |
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* |
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* @return mixed |
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*/ |
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public static function get_public_key( $user_id, $force = false ) { |
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$key = get_user_meta( $user_id, 'magic_sig_public_key' ); |
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|
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if ( $key && ! $force ) { |
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return $key[0]; |
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} |
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|
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self::generate_key_pair( $user_id ); |
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$key = get_user_meta( $user_id, 'magic_sig_public_key' ); |
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|
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return $key[0]; |
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} |
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|
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/** |
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* @param int $user_id |
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* |
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* @return mixed |
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*/ |
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public static function get_private_key( $user_id, $force = false ) { |
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$key = get_user_meta( $user_id, 'magic_sig_private_key' ); |
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|
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if ( $key && ! $force ) { |
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return $key[0]; |
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} |
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|
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self::generate_key_pair( $user_id ); |
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$key = get_user_meta( $user_id, 'magic_sig_private_key' ); |
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|
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return $key[0]; |
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} |
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|
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/** |
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* Generates the pair keys |
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* |
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* @param int $user_id |
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*/ |
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public static function generate_key_pair( $user_id ) { |
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$config = array( |
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'digest_alg' => 'sha512', |
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'private_key_bits' => 2048, |
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'private_key_type' => OPENSSL_KEYTYPE_RSA, |
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); |
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|
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$key = openssl_pkey_new( $config ); |
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$priv_key = null; |
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|
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openssl_pkey_export( $key, $priv_key ); |
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|
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// private key |
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update_user_meta( $user_id, 'magic_sig_private_key', $priv_key ); |
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|
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$detail = openssl_pkey_get_details( $key ); |
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|
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// public key |
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update_user_meta( $user_id, 'magic_sig_public_key', $detail['key'] ); |
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} |
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|
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public static function generate_signature( $user_id, $url, $date ) { |
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$key = self::get_private_key( $user_id ); |
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|
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$url_parts = wp_parse_url( $url ); |
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|
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$host = $url_parts['host']; |
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$path = '/'; |
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|
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// add path |
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if ( ! empty( $url_parts['path'] ) ) { |
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$path = $url_parts['path']; |
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} |
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|
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// add query |
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if ( ! empty( $url_parts['query'] ) ) { |
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$path .= '?' . $url_parts['query']; |
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} |
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|
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$signed_string = "(request-target): post $path\nhost: $host\ndate: $date"; |
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|
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$signature = null; |
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openssl_sign( $signed_string, $signature, $key, OPENSSL_ALGO_SHA256 ); |
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$signature = base64_encode( $signature ); // phpcs:ignore |
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|
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$key_id = get_author_posts_url( $user_id ) . '#main-key'; |
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|
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return sprintf( 'keyId="%s",algorithm="rsa-sha256",headers="(request-target) host date",signature="%s"', $key_id, $signature ); |
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} |
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|
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public static function verify_signature( $headers, $signature ) { |
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|
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} |
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} |
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|
