implement sessions and also log in/out

session data is stored in sqlite, not using php sessions

6 files changed, 144 insertions, 4 deletions

diff --git a/Psso/AuthInterface/UserExists.php b/Psso/AuthInterface/UserExists.php
new file mode 100644
index 0000000..a75d5c6
--- /dev/null
+++ b/Psso/AuthInterface/UserExists.php
@@ -0,0 +1,6 @@
+<?php
+namespace Psso\AuthInterface;
+
+interface UserExists {
+    public function userExists(string $username): bool;
+}
diff --git a/Psso/AuthProvider/ConfigFile.php b/Psso/AuthProvider/ConfigFile.php
index 0d855d0..688c193 100644
--- a/Psso/AuthProvider/ConfigFile.php
+++ b/Psso/AuthProvider/ConfigFile.php
@@ -2,15 +2,20 @@
 namespace Psso\AuthProvider;
 use Psso\{AuthProvider, AuthInterface};
 
-class ConfigFile extends AuthProvider implements AuthInterface\Password {
+class ConfigFile extends AuthProvider
+implements AuthInterface\Password, AuthInterface\UserExists {
     public function validatePassword(
         string $username,
         #[\SensitiveParameter] string $password
     ): bool {
-        $hash = $this->config['users']["$username.password-hash"] ?? null;
+        $hash = $this->config['users'][$username]['password-hash'] ?? null;
         if (!isset($hash)) {
             return false;
         }
         return password_verify($password, $hash);
     }
+
+    public function userExists(string $username): bool {
+        return isset($this->config['users'][$username]);
+    }
 }
diff --git a/Psso/Challenge/Username.php b/Psso/Challenge/Username.php
index 43de085..c8fa762 100644
--- a/Psso/Challenge/Username.php
+++ b/Psso/Challenge/Username.php
@@ -1,6 +1,6 @@
 <?php
 namespace Psso\Challenge;
-use Psso\{Challenge, AuthProvider, ChallengeResult, Input};
+use Psso\{Challenge, AuthProvider, AuthInterface, ChallengeResult, Input};
 
 /** Just asks for a username and sets it in the context. Always succeeds. */
 class Username extends Challenge {
@@ -11,6 +11,14 @@ class Username extends Challenge {
     public function validate(
         AuthProvider $provider, array $inputData
     ): ChallengeResult {
-        return new ChallengeResult(self::class, true, $inputData['user'], null);
+        $success = true;
+        $message = null;
+        if ($provider instanceof AuthInterface\UserExists) {
+            $success = $provider->userExists($inputData['user']);
+            if (!$success) $message = 'challenge.message.wrong-username';
+        }
+        return new ChallengeResult(
+            self::class, $success, $inputData['user'], $message
+        );
     }
 }
diff --git a/Psso/Context.php b/Psso/Context.php
index 4a2cd82..5af2102 100644
--- a/Psso/Context.php
+++ b/Psso/Context.php
@@ -10,4 +10,12 @@ class Context {
     public function addResult(ChallengeResult $result): void {
         $this->results[] = $result;
     }
+
+    public function setTag(string $tag): void {
+        if (!$this->hasTag($tag)) $this->tags[] = $tag;
+    }
+
+    public function hasTag(string $tag): bool {
+        return in_array($tag, $this->tags);
+    }
 }
diff --git a/Psso/Identity.php b/Psso/Identity.php
new file mode 100644
index 0000000..68272d4
--- /dev/null
+++ b/Psso/Identity.php
@@ -0,0 +1,12 @@
+<?php
+namespace Psso;
+
+class Identity {
+    public protected(set) string $user;
+    public protected(set) array $groups;
+
+    public function __construct(string $user, array $groups = []) {
+        $this->user = $user;
+        $this->groups = $groups;
+    }
+}
diff --git a/Psso/Session.php b/Psso/Session.php
new file mode 100644
index 0000000..35a6228
--- /dev/null
+++ b/Psso/Session.php
@@ -0,0 +1,101 @@
+<?php
+namespace Psso;
+
+class Session {
+    protected static ?self $instance = null;
+    protected static ?array $pdoSetup = null;
+    protected static ?array $config = null;
+
+    protected \PDO $db;
+    private ?string $token = null;
+
+    public static function setDsn(
+        array $config,
+        string $dsn,
+        ?string $username = null,
+        #[\SensitiveParameter] ?string $password = null
+    ): void {
+        static::$config = $config;
+        static::$pdoSetup = [$dsn, $username, $password];
+    }
+
+    protected function __construct() {
+        $args = static::$pdoSetup;
+        $args[] = [\PDO::ATTR_PERSISTENT => true];
+        $this->db = new \PDO(...$args);
+        $this->setup();
+    }
+
+    public static function get(): self {
+        if (!isset(self::$instance)) {
+            self::$instance = new self();
+        }
+        self::$instance->setCookie();
+        return self::$instance;
+    }
+
+    protected function setup(): void {
+        $this->db->exec(
+            <<<'END'
+            create table if not exists session (
+                token text primary key not null,
+                identity text not null default 'N;',
+                challenges text not null default 'N;'
+            );
+            END
+        );
+    }
+
+    protected function domain(): string {
+        return explode('.', $_SERVER['HTTP_HOST'], 2)[1];
+    }
+
+    protected function setCookie(): void {
+        if (isset($_COOKIE['PSSO_session'])) return;
+        header(
+            'Set-Cookie: PSSO_session=' . $this->currentToken()
+          . '; Domain=' . $this->domain()
+          . '; HttpOnly'
+          . '; Max-Age=' . static::$config['auth']['lifetime']
+          . '; Path=/'
+          . '; SameSite=Lax'
+          . '; Secure'
+        );
+    }
+
+    protected function currentToken(): string {
+        return $this->token = $this->token ??
+                              $_COOKIE['PSSO_session'] ??
+                              base64_encode(random_bytes(129));
+    }
+
+    protected function setColumn(string $column, mixed $data): void {
+        $stmt = $this->db->prepare(
+            "insert into session(token, $column) values (?, ?) "
+          . "on conflict do update set $column=excluded.$column"
+        );
+        $stmt->execute([$this->currentToken(), serialize($data)]);
+    }
+
+    public function getColumn(string $column): mixed {
+        $stmt = $this->db->prepare("select $column from session where token=?");
+        $stmt->execute([$this->currentToken()]);
+        return unserialize($stmt->fetchColumn(0));
+    }
+
+    public function setIdentity(mixed $identity): void {
+        $this->setColumn('identity', $identity);
+    }
+
+    public function getIdentity(): mixed {
+        return $this->getColumn('identity');
+    }
+
+    public function setChallenges(mixed $challenges): void {
+        $this->setColumn('challenges', $challenges);
+    }
+
+    public function getChallenges(): mixed {
+        return $this->getColumn('challenges');
+    }
+}