From patchwork Sun Oct 25 13:15:55 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jeremy Sowden X-Patchwork-Id: 1387231 X-Patchwork-Delegate: pablo@netfilter.org Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=vger.kernel.org (client-ip=23.128.96.18; helo=vger.kernel.org; envelope-from=netfilter-devel-owner@vger.kernel.org; receiver=) Authentication-Results: ozlabs.org; dmarc=fail (p=none dis=none) header.from=azazel.net Authentication-Results: ozlabs.org; dkim=fail reason="signature verification failed" (2048-bit key; secure) header.d=azazel.net header.i=@azazel.net header.a=rsa-sha256 header.s=20190108 header.b=CJD6FfMM; dkim-atps=neutral Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by ozlabs.org (Postfix) with ESMTP id 4CJz5w2Jy8z9sSG for ; Mon, 26 Oct 2020 00:17:24 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1416236AbgJYNRY (ORCPT ); Sun, 25 Oct 2020 09:17:24 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:37160 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2894311AbgJYNRX (ORCPT ); Sun, 25 Oct 2020 09:17:23 -0400 Received: from kadath.azazel.net (unknown [IPv6:2001:8b0:135f:bcd1:e0cb:4eff:fedf:e608]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 34522C0613CE for ; Sun, 25 Oct 2020 06:17:23 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=azazel.net; s=20190108; h=Content-Transfer-Encoding:MIME-Version:References:In-Reply-To: Message-Id:Date:Subject:Cc:To:From:Sender:Reply-To:Content-Type:Content-ID: Content-Description:Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc :Resent-Message-ID:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=IYyh5vs68YaNUTYimxZm0quFKnVREld0VIcyP4xy0B0=; b=CJD6FfMMj/6A8dDD5woL1xWEZ5 YghXXjD2IjbDMc7J0Tah0EtHDzDYwMbbMku9H/jJW8mwMYw6i24O98gfzK048k7RMlqoUC/dUu413 xXqh8LXsNVrY34+tqMiYQjYopIwo0H03zSDqsWuFUUerw9YtxuQ/gZi7mZvacrl9xz6kDMd+g+8NC 8amRZLjgVc/3QX4x90zaBU3VARTAL0RF+E45VFrdnCnhk4t4r4usuP3iXEOH/T5vg7vY6G8g4s/hr e6DrTp+62IBn4ENdOJ+FewYYIZmG+69+nNSC8l4CbJzSKo37uTqABZLl+/mhTFTvHqH8OarbWo01k aH3/NO7w==; Received: from ulthar.dreamlands.azazel.net ([2001:8b0:fb7d:d6d7:2e4d:54ff:fe4b:a9ae]) by kadath.azazel.net with esmtp (Exim 4.92) (envelope-from ) id 1kWfsW-0001SE-0V; Sun, 25 Oct 2020 13:16:08 +0000 From: Jeremy Sowden To: Jan Engelhardt Cc: Netfilter Devel Subject: [PATCH xtables-addons v2 09/13] pknock: pknlusr: fix hard-coded netlink multicast group ID. Date: Sun, 25 Oct 2020 13:15:55 +0000 Message-Id: <20201025131559.920038-11-jeremy@azazel.net> X-Mailer: git-send-email 2.28.0 In-Reply-To: <20201025131559.920038-1-jeremy@azazel.net> References: <20201025131559.920038-1-jeremy@azazel.net> MIME-Version: 1.0 X-SA-Exim-Connect-IP: 2001:8b0:fb7d:d6d7:2e4d:54ff:fe4b:a9ae X-SA-Exim-Mail-From: jeremy@azazel.net X-SA-Exim-Scanned: No (on kadath.azazel.net); SAEximRunCond expanded to false Precedence: bulk List-ID: X-Mailing-List: netfilter-devel@vger.kernel.org The group ID used by xt_pknock is configurable, but pknlusr hard-codes it. Modify pknlusr to accept an optional ID from the command-line. Group ID's range from 1 to 32 and each ID appears in the group bit-mask at position `group_id - 1`. Signed-off-by: Jeremy Sowden --- extensions/pknock/pknlusr.c | 41 +++++++++++++++++++++++++++++++++---- 1 file changed, 37 insertions(+), 4 deletions(-) diff --git a/extensions/pknock/pknlusr.c b/extensions/pknock/pknlusr.c index fba628e1f466..255649aefbb5 100644 --- a/extensions/pknock/pknlusr.c +++ b/extensions/pknock/pknlusr.c @@ -7,15 +7,22 @@ #include #include #include +#include +#include +#include #include "xt_pknock.h" -#define GROUP 1 +#define DEFAULT_GROUP_ID 1 -int main(void) +#define MIN_GROUP_ID DEFAULT_GROUP_ID +#define MAX_GROUP_ID \ + (sizeof ((struct sockaddr_nl) { 0 }.nl_groups) * CHAR_BIT) + +int main(int argc, char **argv) { int status; - int group = GROUP; + unsigned int group_id = DEFAULT_GROUP_ID; struct sockaddr_nl local_addr = { .nl_family = AF_NETLINK }; int sock_fd; @@ -25,6 +32,32 @@ int main(void) struct cn_msg *cn_msg; struct xt_pknock_nl_msg *pknock_msg; + if (argc > 2) { + char *prog; + if (!(prog = strdup (argv[0]))) { + perror("strdup()"); + } else { + fprintf(stderr, "%s [ group-id ]\n", basename(prog)); + free(prog); + } + exit(EXIT_FAILURE); + } + + if (argc == 2) { + long n; + char *end; + + errno = 0; + n = strtol(argv[1], &end, 10); + if (*end || (errno && (n == LONG_MIN || n == LONG_MAX)) || + n < MIN_GROUP_ID || n > MAX_GROUP_ID) { + fputs("Group ID invalid.\n", stderr); + exit(EXIT_FAILURE); + } + + group_id = n; + } + sock_fd = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_CONNECTOR); if (sock_fd == -1) { @@ -32,7 +65,7 @@ int main(void) exit (EXIT_FAILURE); } - local_addr.nl_groups = group; + local_addr.nl_groups = 1U << (group_id - 1); status = bind(sock_fd, (struct sockaddr*)&local_addr, sizeof(local_addr));