allow saving/loading of kerberos tickets

src/KerberosAuth.php

@@ -27,6 +27,17 @@ use Icewind\SMB\Exception\Exception;
  * Use existing kerberos ticket to authenticate
  */
 class KerberosAuth implements IAuth {
+	/** @var ?KerberosTicket */
+	protected $ticket = null;
+
+	public function getTicket(): ?KerberosTicket {
+		return $this->ticket;
+	}
+
+	public function setTicket(KerberosTicket $ticket): void {
+		$this->ticket = $ticket;
+	}
+
 	public function getUsername(): ?string {
 		return 'dummy';
 	}
@@ -39,11 +50,25 @@ class KerberosAuth implements IAuth {
 		return null;
 	}
 
+	private function setEnv():void {
+		$ticket = $this->getTicket();
+		if ($ticket) {
+			$ticket->validate();
+
+			// note that even if the ticket name is the value we got from `getenv("KRB5CCNAME")` we still need to set the env variable ourselves
+			// this is because `getenv` also reads the variables passed from the SAPI (apache-php) and we need to set the variable in the OS's env
+			putenv("KRB5CCNAME=" . $ticket->getCacheName());
+		}
+	}
+
 	public function getExtraCommandLineArguments(): string {
+		$this->setEnv();
 		return '-k';
 	}
 
 	public function setExtraSmbClientOptions($smbClientState): void {
+		$this->setEnv();
+
 		$success = (bool)smbclient_option_set($smbClientState, SMBCLIENT_OPT_USE_KERBEROS, true);
 		$success = $success && smbclient_option_set($smbClientState, SMBCLIENT_OPT_FALLBACK_AFTER_KERBEROS, false);