diff --git a/misuzu.php b/misuzu.php
index da98bed1..53662df6 100644
--- a/misuzu.php
+++ b/misuzu.php
@@ -39,7 +39,6 @@ require_once 'src/audit_log.php';
 require_once 'src/changelog.php';
 require_once 'src/colour.php';
 require_once 'src/comments.php';
-require_once 'src/csrf.php';
 require_once 'src/manage.php';
 require_once 'src/news.php';
 require_once 'src/perms.php';
@@ -456,10 +455,8 @@ MIG;
         }
     }
 
-    csrf_settings(
-        Config::get('csrf.secret', Config::TYPE_STR, 'insecure'),
-        empty($userDisplayInfo) ? ip_remote_address() : $cookieData['session_token']
-    );
+    CSRF::setGlobalSecretKey(Config::get('csrf.secret', Config::TYPE_STR, 'soup'));
+    CSRF::setGlobalIdentity(empty($userDisplayInfo) ? ip_remote_address() : $cookieData['session_token']);
 
     if(Config::get('private.enabled', Config::TYPE_BOOL)) {
         $onLoginPage = $_SERVER['PHP_SELF'] === url('auth-login');
diff --git a/public/auth/login.php b/public/auth/login.php
index 4246a848..798e2d89 100644
--- a/public/auth/login.php
+++ b/public/auth/login.php
@@ -24,7 +24,7 @@ $ipAddress = ip_remote_address();
 $remainingAttempts = user_login_attempts_remaining($ipAddress);
 
 while(!empty($_POST['login']) && is_array($_POST['login'])) {
-    if(!csrf_verify_request()) {
+    if(!CSRF::validateRequest()) {
         $notices[] = 'Was unable to verify the request, please try again!';
         break;
     }
diff --git a/public/auth/logout.php b/public/auth/logout.php
index 69649732..8e03e58c 100644
--- a/public/auth/logout.php
+++ b/public/auth/logout.php
@@ -8,7 +8,7 @@ if(!user_session_active()) {
     return;
 }
 
-if(csrf_verify_request()) {
+if(CSRF::validateRequest()) {
     setcookie('msz_auth', '', -9001, '/', '', !empty($_SERVER['HTTPS']), true);
     user_session_stop(true);
     url_redirect('index');
diff --git a/public/auth/password.php b/public/auth/password.php
index 2536c2bc..262bf7c4 100644
--- a/public/auth/password.php
+++ b/public/auth/password.php
@@ -30,7 +30,7 @@ $remainingAttempts = user_login_attempts_remaining($ipAddress);
 
 while($canResetPassword) {
     if(!empty($reset) && $userId > 0) {
-        if(!csrf_verify_request()) {
+        if(!CSRF::validateRequest()) {
             $notices[] = 'Was unable to verify the request, please try again!';
             break;
         }
@@ -73,7 +73,7 @@ while($canResetPassword) {
     }
 
     if(!empty($forgot)) {
-        if(!csrf_verify_request()) {
+        if(!CSRF::validateRequest()) {
             $notices[] = 'Was unable to verify the request, please try again!';
             break;
         }
diff --git a/public/auth/register.php b/public/auth/register.php
index 589c8168..3ca9c6ef 100644
--- a/public/auth/register.php
+++ b/public/auth/register.php
@@ -18,7 +18,7 @@ $restricted = ip_blacklist_check(ip_remote_address()) ? 'blacklist'
     : (user_warning_check_ip(ip_remote_address()) ? 'ban' : '');
 
 while(!$restricted && !empty($register)) {
-    if(!csrf_verify_request()) {
+    if(!CSRF::validateRequest()) {
         $notices[] = 'Was unable to verify the request, please try again!';
         break;
     }
diff --git a/public/auth/twofactor.php b/public/auth/twofactor.php
index ba2bb521..04656ef3 100644
--- a/public/auth/twofactor.php
+++ b/public/auth/twofactor.php
@@ -26,7 +26,7 @@ if(empty($tokenInfo['user_totp_key'])) {
 }
 
 while(!empty($twofactor)) {
-    if(!csrf_verify_request()) {
+    if(!CSRF::validateRequest()) {
         $notices[] = 'Was unable to verify the request, please try again!';
         break;
     }
diff --git a/public/comments.php b/public/comments.php
index e2c11a1f..84353d60 100644
--- a/public/comments.php
+++ b/public/comments.php
@@ -15,7 +15,7 @@ if($isXHR) {
     return;
 }
 
-if(!csrf_verify_request()) {
+if(!CSRF::validateRequest()) {
     echo render_info_or_json($isXHR, "Couldn't verify this request, please refresh the page and try again.", 403);
     return;
 }
@@ -36,7 +36,7 @@ if(user_warning_check_expiration($currentUserId, MSZ_WARN_SILENCE) > 0) {
     return;
 }
 
-csrf_http_header();
+header(CSRF::header());
 $commentPerms = comments_get_perms($currentUserId);
 
 $commentId = !empty($_GET['c']) && is_string($_GET['c']) ? (int)$_GET['c'] : 0;
diff --git a/public/forum/index.php b/public/forum/index.php
index 1a48b6e2..c5e4813e 100644
--- a/public/forum/index.php
+++ b/public/forum/index.php
@@ -10,7 +10,7 @@ switch($indexMode) {
     case 'mark':
         $markEntireForum = $forumId === 0;
 
-        if(user_session_active() && csrf_verify_request()) {
+        if(user_session_active() && CSRF::validateRequest()) {
             forum_mark_read($markEntireForum ? null : $forumId, user_session_current('user_id', 0));
         }
 
diff --git a/public/forum/poll.php b/public/forum/poll.php
index 6055464a..69bca4c2 100644
--- a/public/forum/poll.php
+++ b/public/forum/poll.php
@@ -13,7 +13,7 @@ if($isXHR) {
     return;
 }
 
-if(!csrf_verify_request()) {
+if(!CSRF::validateRequest()) {
     echo render_info_or_json($isXHR, "Couldn't verify this request, please refresh the page and try again.", 403);
     return;
 }
@@ -34,7 +34,7 @@ if(user_warning_check_expiration($currentUserId, MSZ_WARN_SILENCE) > 0) {
     return;
 }
 
-csrf_http_header();
+header(CSRF::header());
 
 if(empty($_POST['poll']['id']) || !ctype_digit($_POST['poll']['id'])) {
     echo render_info_or_json($isXHR, "Invalid request.", 400);
diff --git a/public/forum/post.php b/public/forum/post.php
index 27df9a0e..655a1a89 100644
--- a/public/forum/post.php
+++ b/public/forum/post.php
@@ -19,7 +19,7 @@ if($isXHR) {
     return;
 }
 
-$postRequestVerified = csrf_verify_request();
+$postRequestVerified = CSRF::validateRequest();
 
 if(!empty($postMode) && !user_session_active()) {
     echo render_info_or_json($isXHR, 'You must be logged in to manage posts.', 401);
@@ -47,7 +47,7 @@ if($isXHR) {
         return;
     }
 
-    csrf_http_header();
+    header(CSRF::header());
 }
 
 $postInfo = forum_post_get($postId, true);
diff --git a/public/forum/posting.php b/public/forum/posting.php
index 3b3f39df..8b1d3f3d 100644
--- a/public/forum/posting.php
+++ b/public/forum/posting.php
@@ -133,7 +133,7 @@ if(!empty($_POST)) {
     $topicType = isset($_POST['post']['type']) ? (int)$_POST['post']['type'] : null;
     $postSignature = isset($_POST['post']['signature']);
 
-    if(!csrf_verify_request()) {
+    if(!CSRF::validateRequest()) {
         $notices[] = 'Could not verify request.';
     } else {
         $isEditingTopic = empty($topic) || ($mode === 'edit' && $post['is_opening_post']);
diff --git a/public/forum/topic.php b/public/forum/topic.php
index ecf4b5a9..79fd8768 100644
--- a/public/forum/topic.php
+++ b/public/forum/topic.php
@@ -82,12 +82,12 @@ if(in_array($moderationMode, $validModerationModes, true)) {
         return;
     }
 
-    if(!csrf_verify_request()) {
+    if(!CSRF::validateRequest()) {
         echo render_info_or_json($isXHR, "Couldn't verify this request, please refresh the page and try again.", 403);
         return;
     }
 
-    csrf_http_header();
+    header(CSRF::header());
 
     if(!user_session_active()) {
         echo render_info_or_json($isXHR, 'You must be logged in to manage posts.', 401);
diff --git a/public/manage/changelog/change.php b/public/manage/changelog/change.php
index 59ab689b..08dd8797 100644
--- a/public/manage/changelog/change.php
+++ b/public/manage/changelog/change.php
@@ -10,7 +10,7 @@ if(!perms_check_user(MSZ_PERMS_CHANGELOG, user_session_current('user_id'), MSZ_P
 
 $changeId = (int)($_GET['c'] ?? 0);
 
-if($_SERVER['REQUEST_METHOD'] === 'POST' && csrf_verify_request()) {
+if($_SERVER['REQUEST_METHOD'] === 'POST' && CSRF::validateRequest()) {
     if(!empty($_POST['change']) && is_array($_POST['change'])) {
         if($changeId > 0) {
             $postChange = DB::prepare('
diff --git a/public/manage/changelog/tag.php b/public/manage/changelog/tag.php
index 9d53793c..3218028a 100644
--- a/public/manage/changelog/tag.php
+++ b/public/manage/changelog/tag.php
@@ -10,7 +10,7 @@ if(!perms_check_user(MSZ_PERMS_CHANGELOG, user_session_current('user_id'), MSZ_P
 
 $tagId = (int)($_GET['t'] ?? 0);
 
-if(!empty($_POST['tag']) && is_array($_POST['tag']) && csrf_verify_request()) {
+if(!empty($_POST['tag']) && is_array($_POST['tag']) && CSRF::validateRequest()) {
     if($tagId > 0) {
         $updateTag = DB::prepare('
             UPDATE `msz_changelog_tags`
diff --git a/public/manage/general/blacklist.php b/public/manage/general/blacklist.php
index 68a4d0db..b78d1c99 100644
--- a/public/manage/general/blacklist.php
+++ b/public/manage/general/blacklist.php
@@ -11,10 +11,10 @@ if(!perms_check_user(MSZ_PERMS_GENERAL, user_session_current('user_id'), General
 $notices = [];
 
 if(!empty($_POST)) {
-    if(!csrf_verify_request()) {
+    if(!CSRF::validateRequest()) {
         $notices[] = 'Verification failed.';
     } else {
-        csrf_http_header();
+        header(CSRF::header());
 
         if(!empty($_POST['blacklist']['remove']) && is_array($_POST['blacklist']['remove'])) {
             foreach($_POST['blacklist']['remove'] as $cidr) {
diff --git a/public/manage/general/emoticon.php b/public/manage/general/emoticon.php
index 7435cde4..44878a2f 100644
--- a/public/manage/general/emoticon.php
+++ b/public/manage/general/emoticon.php
@@ -12,7 +12,7 @@ $emoteId = !empty($_GET['e']) && is_string($_GET['e']) ? (int)$_GET['e'] : 0;
 $isNew = $emoteId <= 0;
 $emoteInfo = !$isNew ? Emoticon::byId($emoteId) : new Emoticon;
 
-if(csrf_verify_request() && isset($_POST['emote_order']) && isset($_POST['emote_hierarchy']) && !empty($_POST['emote_url']) && !empty($_POST['emote_strings'])) {
+if(CSRF::validateRequest() && isset($_POST['emote_order']) && isset($_POST['emote_hierarchy']) && !empty($_POST['emote_url']) && !empty($_POST['emote_strings'])) {
     $emoteInfo->setUrl($_POST['emote_url'])
         ->setHierarchy($_POST['emote_hierarchy'])
         ->setOrder($_POST['emote_order'])
diff --git a/public/manage/general/emoticons.php b/public/manage/general/emoticons.php
index 4151635f..a2255220 100644
--- a/public/manage/general/emoticons.php
+++ b/public/manage/general/emoticons.php
@@ -8,7 +8,7 @@ if(!perms_check_user(MSZ_PERMS_GENERAL, user_session_current('user_id'), General
     return;
 }
 
-if(csrf_verify_request() && !empty($_GET['emote']) && is_string($_GET['emote'])) {
+if(CSRF::validateRequest() && !empty($_GET['emote']) && is_string($_GET['emote'])) {
     $emoteId = (int)$_GET['emote'];
     $emoteInfo = Emoticon::byId($emoteId);
 
diff --git a/public/manage/news/category.php b/public/manage/news/category.php
index 20ef1622..bb9e94c6 100644
--- a/public/manage/news/category.php
+++ b/public/manage/news/category.php
@@ -11,7 +11,7 @@ if(!perms_check_user(MSZ_PERMS_NEWS, user_session_current('user_id'), MSZ_PERM_N
 $category = [];
 $categoryId = (int)($_GET['c'] ?? null);
 
-if(!empty($_POST['category']) && csrf_verify_request()) {
+if(!empty($_POST['category']) && CSRF::validateRequest()) {
     $originalCategoryId = (int)($_POST['category']['id'] ?? null);
     $categoryId = news_category_create(
         $_POST['category']['name'] ?? null,
diff --git a/public/manage/news/post.php b/public/manage/news/post.php
index b71ff875..cd53ad16 100644
--- a/public/manage/news/post.php
+++ b/public/manage/news/post.php
@@ -12,7 +12,7 @@ $post = [];
 $postId = (int)($_GET['p'] ?? null);
 $categories = news_categories_get(0, 0, false, false, true);
 
-if(!empty($_POST['post']) && csrf_verify_request()) {
+if(!empty($_POST['post']) && CSRF::validateRequest()) {
     $originalPostId = (int)($_POST['post']['id'] ?? null);
     $currentUserId = user_session_current('user_id');
     $title = $_POST['post']['title'] ?? null;
diff --git a/public/manage/users/role.php b/public/manage/users/role.php
index cc8b825e..9abb1bf0 100644
--- a/public/manage/users/role.php
+++ b/public/manage/users/role.php
@@ -20,7 +20,7 @@ if($canEditPerms) {
     $permissions = manage_perms_list(perms_get_role_raw($roleId ?? 0));
 }
 
-if(!empty($_POST['role']) && is_array($_POST['role']) && csrf_verify_request()) {
+if(!empty($_POST['role']) && is_array($_POST['role']) && CSRF::validateRequest()) {
     $roleHierarchy = (int)($_POST['role']['hierarchy'] ?? -1);
 
     if(!user_check_super($currentUserId) && ($roleId === null
diff --git a/public/manage/users/user.php b/public/manage/users/user.php
index 0248ad75..76a40bb4 100644
--- a/public/manage/users/user.php
+++ b/public/manage/users/user.php
@@ -22,7 +22,7 @@ $canEdit = $isSuperUser || user_check_authority($currentUserId, $userId);
 $canEditPerms = $canEdit && perms_check_user(MSZ_PERMS_USER, $currentUserId, MSZ_PERM_USER_MANAGE_PERMS);
 $permissions = manage_perms_list(perms_get_user_raw($userId));
 
-if(csrf_verify_request() && $canEdit) {
+if(CSRF::validateRequest() && $canEdit) {
     if(!empty($_POST['roles']) && is_array($_POST['roles']) && array_test($_POST['roles'], 'ctype_digit')) {
         // Fetch existing roles
         $existingRoles = DB::prepare('
diff --git a/public/profile.php b/public/profile.php
index 4ae08710..83b3e24b 100644
--- a/public/profile.php
+++ b/public/profile.php
@@ -62,7 +62,7 @@ if($isEditing) {
     ]);
 
     if(!empty($_POST) && is_array($_POST)) {
-        if(!csrf_verify_request()) {
+        if(!CSRF::validateRequest()) {
             $notices[] = MSZ_TMP_USER_ERROR_STRINGS['csrf'];
         } else {
             if(!empty($_POST['profile']) && is_array($_POST['profile'])) {
diff --git a/public/relations.php b/public/relations.php
index 34182915..8e3bb363 100644
--- a/public/relations.php
+++ b/public/relations.php
@@ -15,12 +15,12 @@ if($isXHR) {
     return;
 }
 
-if(!csrf_verify_request()) {
+if(!CSRF::validateRequest()) {
     echo render_info_or_json($isXHR, "Couldn't verify this request, please refresh the page and try again.", 403);
     return;
 }
 
-csrf_http_header();
+header(CSRF::header());
 
 if(!user_session_active()) {
     echo render_info_or_json($isXHR, 'You must be logged in to manage relations.', 401);
diff --git a/public/settings/account.php b/public/settings/account.php
index a178268a..59749a28 100644
--- a/public/settings/account.php
+++ b/public/settings/account.php
@@ -16,7 +16,7 @@ $currentUserId = user_session_current('user_id');
 $currentEmail = user_email_get($currentUserId);
 $isRestricted = user_warning_check_restriction($currentUserId);
 $twoFactorInfo = user_totp_info($currentUserId);
-$isVerifiedRequest = csrf_verify_request();
+$isVerifiedRequest = CSRF::validateRequest();
 
 if(!$isRestricted && $isVerifiedRequest && !empty($_POST['role'])) {
     $roleId = (int)($_POST['role']['id'] ?? 0);
diff --git a/public/settings/sessions.php b/public/settings/sessions.php
index 28bf52ad..1179bc4a 100644
--- a/public/settings/sessions.php
+++ b/public/settings/sessions.php
@@ -12,7 +12,7 @@ $errors = [];
 $currentUserId = user_session_current('user_id');
 $sessionActive = user_session_current('session_id');
 
-if(!empty($_POST['session']) && csrf_verify_request()) {
+if(!empty($_POST['session']) && CSRF::validateRequest()) {
     $currentSessionKilled = false;
 
     if(is_array($_POST['session'])) {
diff --git a/src/CSRF.php b/src/CSRF.php
new file mode 100644
index 00000000..566de84f
--- /dev/null
+++ b/src/CSRF.php
@@ -0,0 +1,112 @@
+<?php
+namespace Misuzu;
+
+use Exception;
+use InvalidArgumentException;
+
+final class CSRF {
+    public const TOLERANCE = 30 * 60;
+    public const HASH_ALGO = 'sha1';
+    public const EPOCH = 1575158400;
+
+    private $timestamp = 0;
+    private $tolerance = 0;
+
+    private static $globalIdentity = '';
+    private static $globalSecretKey = '';
+
+    public function __construct(int $tolerance = self::TOLERANCE, ?int $timestamp = null) {
+        $this->setTolerance($tolerance);
+        $this->setTimestamp($timestamp ?? self::timestamp());
+    }
+
+    public static function timestamp(): int {
+        return time() - self::EPOCH;
+    }
+
+    public static function setGlobalIdentity(string $identity): void {
+        self::$globalIdentity = $identity;
+    }
+    public static function setGlobalSecretKey(string $secretKey): void {
+        self::$globalSecretKey = $secretKey;
+    }
+    public static function validate(string $token, ?string $identity = null, ?string $secretKey = null): bool {
+        try {
+            return self::decode($token, $identity ?? self::$globalIdentity, $secretKey ?? self::$globalSecretKey)->isValid();
+        } catch(Exception $ex) {
+            return false;
+        }
+    }
+    public static function token(?string $identity = null, int $tolerance = self::TOLERANCE, ?string $secretKey = null, ?int $timestamp = null): string {
+        return (new static($tolerance, $timestamp))->encode($identity ?? self::$globalIdentity, $secretKey ?? self::$globalSecretKey);
+    }
+
+    // Should be replaced by filters eventually <
+    public static function header(...$args): string {
+        return 'X-Misuzu-CSRF: ' . self::token(...$args);
+    }
+    public static function validateRequest(?string $identity = null, ?string $secretKey = null): bool {
+        if(isset($_SERVER['HTTP_X_MISUZU_CSRF'])) {
+            $token = $_SERVER['HTTP_X_MISUZU_CSRF'];
+        } elseif(isset($_POST['_csrf']) && is_string($_POST['_csrf'])) {
+            $token = $_POST['_csrf'];
+        } elseif(isset($_REQUEST['csrf']) && is_string($_REQUEST['csrf'])) {
+            $token = $_REQUEST['csrf'];
+        } else {
+            return false;
+        }
+
+        return self::validate($token, $identity, $secretKey);
+    }
+    // >
+
+    public static function decode(string $token, string $identity, string $secretKey): CSRF {
+        $hash = substr($token, 12);
+        $unpacked = unpack('Vtimestamp/vtolerance', hex2bin(substr($token, 0, 12)));
+
+        if(empty($hash) || empty($unpacked['timestamp']) || empty($unpacked['tolerance']))
+            throw new InvalidArgumentException('Invalid token provided.');
+
+        $csrf = new static($unpacked['tolerance'], $unpacked['timestamp']);
+
+        if(!hash_equals($csrf->getHash($identity, $secretKey), $hash))
+            throw new InvalidArgumentException('Modified token.');
+
+        return $csrf;
+    }
+
+    public function encode(string $identity, string $secretKey): string {
+        $token = bin2hex(pack('Vv', $this->getTimestamp(), $this->getTolerance()));
+        $token .= $this->getHash($identity, $secretKey);
+        return $token;
+    }
+
+    public function getHash(string $identity, string $secretKey): string {
+        return hash_hmac(self::HASH_ALGO, "{$identity}|{$this->getTimestamp()}|{$this->getTolerance()}", $secretKey);
+    }
+
+    public function getTimestamp(): int {
+        return $this->timestamp;
+    }
+    public function setTimestamp(int $timestamp): self {
+        if($timestamp < 0 || $timestamp > 0xFFFFFFFF)
+            throw new InvalidArgumentException('Timestamp must be within the constaints of an unsigned 32-bit integer.');
+        $this->timestamp = $timestamp;
+        return $this;
+    }
+
+    public function getTolerance(): int {
+        return $this->tolerance;
+    }
+    public function setTolerance(int $tolerance): self {
+        if($tolerance < 0 || $tolerance > 0xFFFF)
+            throw new InvalidArgumentException('Tolerance must be within the constaints of an unsigned 16-bit integer.');
+        $this->tolerance = $tolerance;
+        return $this;
+    }
+
+    public function isValid(): bool {
+        $currentTime = self::timestamp();
+        return $currentTime >= $this->getTimestamp() && $currentTime <= $this->getTimestamp() + $this->getTolerance();
+    }
+}
diff --git a/src/TwigMisuzu.php b/src/TwigMisuzu.php
index 880cb26e..bfa29e17 100644
--- a/src/TwigMisuzu.php
+++ b/src/TwigMisuzu.php
@@ -32,8 +32,6 @@ final class TwigMisuzu extends Twig_Extension {
     public function getFunctions() {
         return [
             new Twig_Function('get_browser', 'get_browser'),
-            new Twig_Function('csrf_token', 'csrf_token'),
-            new Twig_Function('csrf_input', 'csrf_html'),
             new Twig_Function('url_construct', 'url_construct'),
             new Twig_Function('warning_has_duration', 'user_warning_has_duration'),
             new Twig_Function('url', 'url'),
@@ -44,6 +42,7 @@ final class TwigMisuzu extends Twig_Extension {
             new Twig_Function('forum_may_have_children', 'forum_may_have_children'),
             new Twig_Function('forum_may_have_topics', 'forum_may_have_topics'),
             new Twig_Function('forum_has_priority_voting', 'forum_has_priority_voting'),
+            new Twig_Function('csrf_token', fn() => CSRF::token()),
             new Twig_Function('git_commit_hash', fn(bool $long = false) => GitInfo::hash($long)),
             new Twig_Function('git_tag', fn() => GitInfo::tag()),
             new Twig_Function('git_branch', fn() => GitInfo::branch()),
diff --git a/src/csrf.php b/src/csrf.php
deleted file mode 100644
index 5e1ca719..00000000
--- a/src/csrf.php
+++ /dev/null
@@ -1,127 +0,0 @@
-<?php
-define('MSZ_CSRF_TOLERANCE', 30 * 60); // DO NOT EXCEED 16-BIT INTEGER SIZES, SHIT _WILL_ BREAK
-define('MSZ_CSRF_HTML', '<input type="hidden" name="csrf" value="%1$s">');
-define('MSZ_CSRF_HASH_ALGO', 'sha256');
-define('MSZ_CSRF_TOKEN_LENGTH', 76); // 8 + 4 + 64
-
-// the following three functions DO NOT depend on csrf_init().
-// $identity = When the user is logged in I recommend just using their session key, otherwise IP will be fine.
-function csrf_token_create(
-    string $identity,
-    string $secretKey,
-    ?int $timestamp = null,
-    int $tolerance = MSZ_CSRF_TOLERANCE
-): string {
-    $timestamp = $timestamp ?? time();
-    $token = bin2hex(pack('Vv', $timestamp, $tolerance));
-
-    return $token . csrf_token_hash(
-        MSZ_CSRF_HASH_ALGO,
-        $identity,
-        $secretKey,
-        $timestamp,
-        $tolerance
-    );
-}
-
-function csrf_token_hash(
-    string $algo,
-    string $identity,
-    string $secretKey,
-    int $timestamp,
-    int $tolerance
-): string {
-    return hash_hmac(
-        $algo,
-        implode(',', [$identity, $timestamp, $tolerance]),
-        $secretKey
-    );
-}
-
-function csrf_token_verify(
-    string $token,
-    string $identity,
-    string $secretKey
-): bool {
-    if(empty($token) || strlen($token) !== MSZ_CSRF_TOKEN_LENGTH) {
-        return false;
-    }
-
-    [$timestamp, $tolerance] = [0, 0];
-    extract(unpack('Vtimestamp/vtolerance', hex2bin(substr($token, 0, 12))));
-
-    if(time() > $timestamp + $tolerance) {
-        return false;
-    }
-
-    // remove timestamp + tolerance from token
-    $token = substr($token, 12);
-
-    $compare = csrf_token_hash(
-        MSZ_CSRF_HASH_ALGO,
-        $identity,
-        $secretKey,
-        $timestamp,
-        $tolerance
-    );
-
-    return hash_equals($compare, $token);
-}
-
-// Sets some defaults
-function csrf_settings(?string $secretKey = null, ?string $identity = null): array {
-    static $settings = [];
-
-    if(!empty($secretKey) && !empty($identity)) {
-        $settings = [
-            'secret_key' => $secretKey,
-            'identity' => $identity,
-        ];
-    }
-
-    return $settings;
-}
-
-function csrf_is_ready(): bool {
-    return !empty(csrf_settings());
-}
-
-function csrf_token(): string {
-    static $token = null;
-
-    if(empty($token)) {
-        $settings = csrf_settings();
-        $token = csrf_token_create(
-            $settings['identity'],
-            $settings['secret_key']
-        );
-    }
-
-    return $token;
-}
-
-function csrf_verify(string $token): bool {
-    $settings = csrf_settings();
-
-    return csrf_token_verify(
-        $token,
-        $settings['identity'],
-        $settings['secret_key']
-    );
-}
-
-function csrf_verify_request(?string $token = null): bool {
-    if(empty($token)) {
-        $token = $_SERVER['HTTP_X_MISUZU_CSRF'] ?? $_REQUEST['csrf'] ?? '';
-    }
-
-    return csrf_verify($token);
-}
-
-function csrf_html(): string {
-    return sprintf(MSZ_CSRF_HTML, csrf_token());
-}
-
-function csrf_http_header(string $name = 'X-Misuzu-CSRF'): void {
-    header("{$name}: " . csrf_token());
-}
diff --git a/src/url.php b/src/url.php
index 4f8bcf34..c3f446c1 100644
--- a/src/url.php
+++ b/src/url.php
@@ -189,8 +189,8 @@ function url_variable(string $value, array $variables): string {
         return constant(trim($value, '[]'));
     }
 
-    if(starts_with($value, '{') && ends_with($value, '}') && csrf_is_ready()) {
-        return csrf_token();
+    if(starts_with($value, '{') && ends_with($value, '}')) {
+        return \Misuzu\CSRF::token();
     }
 
     return $value;
diff --git a/templates/_layout/input.twig b/templates/_layout/input.twig
index c8c93ecc..ded87663 100644
--- a/templates/_layout/input.twig
+++ b/templates/_layout/input.twig
@@ -4,9 +4,10 @@
 {% endspaceless %}
 {% endmacro %}
 
-{% macro input_csrf() %}{# so we don't have to specify |raw every time #}
+{% macro input_csrf() %}
+{% from _self import input_hidden %}
 {% spaceless %}
-    {{ csrf_input()|raw }}
+    {{ input_hidden('_csrf', csrf_token()) }}
 {% endspaceless %}
 {% endmacro %}