From patchwork Thu Oct 3 00:50:42 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Matthieu Buffet X-Patchwork-Id: 13820592 Received: from mx1.buffet.re (mx1.buffet.re [51.83.41.69]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id B0BFADDAB; Thu, 3 Oct 2024 00:50:27 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=51.83.41.69 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727916630; cv=none; b=mcIt4QY6MumQtbr/GevXHhyEiTmzKKTEKLWGkkxcyIKH8q+JrIeC31iuQDbCbFSvUspe205fEWy80Hs7GVG555PbQePMHYYRdNEw1Ro9oIIAmuStFiJZ52gIV+ysL8IRhagDn5KulberSaIMZVILfZ9tAeSERs7NrppYeL6uj2Y= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1727916630; c=relaxed/simple; bh=SFt8Izw3k9oW8PRPnRr3j1kF25WKNW3bL1ymvtdIDvw=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=ai8d+AJ1zn3b60qpzo+yTAUkbW/Hf2HfagMpIk7belGk4I0M/SSbFs+FUtY8i9P3AC5CO1a5WsdxGqh0w+vZ19zNMVcW47vyNG5VsOxT0vnRmESUEqUKvsLg4vfRO0K8TXGXK5xEE/SRzeI9KR7SU5h38yWG01HZbyPF4bBbXrE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=buffet.re; spf=pass smtp.mailfrom=buffet.re; dkim=pass (2048-bit key) header.d=buffet.re header.i=@buffet.re header.b=haQ4uImw; arc=none smtp.client-ip=51.83.41.69 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=buffet.re Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=buffet.re Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=buffet.re header.i=@buffet.re header.b="haQ4uImw" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=buffet.re; s=mx1; t=1727916620; bh=SFt8Izw3k9oW8PRPnRr3j1kF25WKNW3bL1ymvtdIDvw=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=haQ4uImwh1ZMug4jCAxX2a/Kjn/JJ/a4K6uNldjeF3wkgO7OBFvtcQN76BlTZQa2L 4vNbGt8CNdeCoXC4RQ0Uri9dT3BxxhMuzE2fCTwmfluD0y+yALCC+bKzT02RWumCyq xUlOdGfsvzjeU3HZ5C4lKdKjjYyJGtWHtE6ZKvnctFMKNCZs07GNGpou/RPtYtYXol 4JmX6v3rVh70RcJieBEFz+FL77M61/y8m9s+pOjl7hXt+8yDx6dOEYNlb6K9J0VPN8 sZsKZTZmHVwqrobwTCK8goUY5kiaBfFsrU1mF7W5Pheg5bhPiCAKSGYFlC6S+0un5C YzfQlsvCgtetA== Received: from localhost.localdomain (unknown [10.0.1.3]) by mx1.buffet.re (Postfix) with ESMTPA id 9525D1230C1; Thu, 3 Oct 2024 02:50:20 +0200 (CEST) From: Matthieu Buffet To: =?utf-8?q?Micka=C3=ABl_Sala=C3=BCn?= Cc: =?utf-8?q?G=C3=BCnther_Noack?= , Konstantin Meskhidze , Ivanov Mikhail , linux-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, Matthieu Buffet Subject: [PATCH v2 3/3] samples/landlock: Clarify option parsing behaviour Date: Thu, 3 Oct 2024 02:50:42 +0200 Message-Id: <20241003005042.258991-3-matthieu@buffet.re> X-Mailer: git-send-email 2.39.2 In-Reply-To: <20241003005042.258991-1-matthieu@buffet.re> References: <20241003005042.258991-1-matthieu@buffet.re> Precedence: bulk X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 - Clarify which environment variables are optional, which ones are mandatory - Clarify the difference between unset variables and empty ones Signed-off-by: Matthieu Buffet --- samples/landlock/sandboxer.c | 22 +++++++++++++--------- 1 file changed, 13 insertions(+), 9 deletions(-) diff --git a/samples/landlock/sandboxer.c b/samples/landlock/sandboxer.c index f16994d35d9e..a28e4a9c5f87 100644 --- a/samples/landlock/sandboxer.c +++ b/samples/landlock/sandboxer.c @@ -298,24 +298,27 @@ static bool check_ruleset_scope(const char *const env_var, static void print_help(const char *argv0) { fprintf(stderr, - "usage: %s=\"...\" %s=\"...\" %s=\"...\" %s=\"...\" %s=\"...\" %s " + "usage: %s=\"...\" %s=\"...\" [other environment variables] %s " " [args]...\n\n", - ENV_FS_RO_NAME, ENV_FS_RW_NAME, ENV_TCP_BIND_NAME, - ENV_TCP_CONNECT_NAME, ENV_SCOPED_NAME, argv0); + ENV_FS_RO_NAME, ENV_FS_RW_NAME, argv0); fprintf(stderr, "Execute a command in a restricted environment.\n\n"); fprintf(stderr, - "Environment variables containing paths and ports " - "each separated by a colon:\n"); + "All environment variables can be multi-valued, with a " + "colon delimiter.\n" + "\n" + "Mandatory settings:\n"); fprintf(stderr, "* %s: list of paths allowed to be used in a read-only way.\n", ENV_FS_RO_NAME); fprintf(stderr, - "* %s: list of paths allowed to be used in a read-write way.\n\n", + "* %s: list of paths allowed to be used in a read-write way.\n", ENV_FS_RW_NAME); fprintf(stderr, - "Environment variables containing ports are optional " - "and could be skipped.\n"); + "\n" + "Optional settings (when not set, their associated access " + "check is always allowed, which is different from an empty " + "string which means an empty list)\n"); fprintf(stderr, "* %s: list of ports allowed to bind (server).\n", ENV_TCP_BIND_NAME); @@ -325,7 +328,8 @@ static void print_help(const char *argv0) fprintf(stderr, "* %s: list of scoped IPCs.\n", ENV_SCOPED_NAME); fprintf(stderr, - "\nexample:\n" + "\n" + "Example:\n" "%s=\"${PATH}:/lib:/usr:/proc:/etc:/dev/urandom\" " "%s=\"/dev/null:/dev/full:/dev/zero:/dev/pts:/tmp\" " "%s=\"9418\" "