From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from ganesha.gnumonks.org (ganesha.gnumonks.org [213.95.27.120]) (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 A6FEC190075 for ; Wed, 10 Jul 2024 14:04:30 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=213.95.27.120 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720620273; cv=none; b=DQCwF6a6KCFdm7mP0bjMCtcpH2XZZEshthDDUHDnvKWJz5x/tRkm+mGXp8v0Hc36e60sXknSoa0Na4t+fg/W4UpBm95ZNi18E5AcyKGuAcvfZYWBluQPd06OFXc+wKLe+A+2Bv0d6bpG08X6wDyvRbFQJSJqyK4RtMxTjnoYT44= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1720620273; c=relaxed/simple; bh=a/4f8ZaqTbNCiUJZucuF7M/w0pm1xWwmFF8F3ZDvwas=; h=Date:From:To:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=tpGoA/7IaJRiLFPJjXETcO+UM3gBjRe6T6wr51rTdDx5Jeuvug0WVBJ7zk49M7rTq7rNrL+cCcGf7nl/+CQq2QYj+oppZAdiW/AZHZNrRNnwoZilJsy99BL8b8WGzpX/LwLror0vNTrNjAj7061N/n3+JUvyDKQjUdF90nYV/gc= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org; spf=pass smtp.mailfrom=gnumonks.org; arc=none smtp.client-ip=213.95.27.120 Authentication-Results: smtp.subspace.kernel.org; dmarc=none (p=none dis=none) header.from=netfilter.org Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=gnumonks.org Received: from [78.30.37.63] (port=55178 helo=gnumonks.org) by ganesha.gnumonks.org with esmtpsa (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.94.2) (envelope-from ) id 1sRXvl-00GczE-UF; Wed, 10 Jul 2024 16:04:28 +0200 Date: Wed, 10 Jul 2024 16:04:25 +0200 From: Pablo Neira Ayuso To: Phil Sutter , netfilter-devel@vger.kernel.org, jami.maenpaa@wapice.com, Thomas Haller Subject: Re: [PATCH nft 1/2] parser_json: use stdin buffer if available Message-ID: References: <20240709145953.135124-1-pablo@netfilter.org> Precedence: bulk X-Mailing-List: netfilter-devel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="iahYZQSa/7dWjrSZ" Content-Disposition: inline In-Reply-To: X-Spam-Score: -1.8 (-) --iahYZQSa/7dWjrSZ Content-Type: text/plain; charset=utf-8 Content-Disposition: inline On Wed, Jul 10, 2024 at 04:01:19PM +0200, Phil Sutter wrote: > On Wed, Jul 10, 2024 at 03:53:52PM +0200, Phil Sutter wrote: > > Hi Pablo, > > > > On Tue, Jul 09, 2024 at 04:59:52PM +0200, Pablo Neira Ayuso wrote: > > > Since 5c2b2b0a2ba7 ("src: error reporting with -f and read from stdin") > > > stdin is stored in a buffer, update json support to use it instead of > > > reading from /dev/stdin. > > > > > > Some systems do not provide /dev/stdin symlink to /proc/self/fd/0 > > > according to reporter (that mentions Yocto Linux as example). > > > > > > Signed-off-by: Pablo Neira Ayuso > > > --- > > > src/parser_json.c | 7 +++++++ > > > 1 file changed, 7 insertions(+) > > > > > > diff --git a/src/parser_json.c b/src/parser_json.c > > > index ee4657ee8044..4912d3608b2b 100644 > > > --- a/src/parser_json.c > > > +++ b/src/parser_json.c > > > @@ -4357,6 +4357,13 @@ int nft_parse_json_filename(struct nft_ctx *nft, const char *filename, > > > json_error_t err; > > > int ret; > > > > > > + if (nft->stdin_buf) { > > > + json_indesc.type = INDESC_STDIN; > > > + json_indesc.name = "/dev/stdin"; > > > + > > > + return nft_parse_json_buffer(nft, nft->stdin_buf, msgs, cmds); > > > + } > > > > Is this sufficient? In nft_run_cmd_from_filename(), nft->stdin_buf is > > populated conditionally: > > > > | if (!strcmp(filename, "/dev/stdin") && > > | !nft_output_json(&nft->output)) > > | nft->stdin_buf = stdin_to_buffer(); > > > > Later (in the wrapped __nft_run_cmd_from_filename()), we try JSON parsing > > conditionally: > > > > | if (nft_output_json(&nft->output) || nft_input_json(&nft->input)) > > | rc = nft_parse_json_filename(nft, filename, &msgs, &cmds); > > > > Things got complicated by commit 2034d8c60ed91 ("src: add input flag > > NFT_CTX_INPUT_JSON to enable JSON parsing") and my request to remain > > compatible, i.e. '-j' flag which enables JSON output shall continue to > > make JSON the assumed input format. > > > > So long story short, I guess in order to cover all cases, we have to > > enable nft->stdin_buf population also if nft_input_json(...) returns > > true, i.e. cover for library users requesting JSON input (but standard > > output). WDYT? > > On second review, I think the right change is to make > nft_run_cmd_from_filename() *always* populate nft->stdin_buf if > 'filename' is '/dev/stdin', i.e. drop the !nft_output_json(...) clause. > > Sorry for the confusion. I can squash this incremental fix to 1/2 send post a v2. Thanks. --iahYZQSa/7dWjrSZ Content-Type: text/x-diff; charset=utf-8 Content-Disposition: attachment; filename="fix.patch" diff --git a/src/libnftables.c b/src/libnftables.c index af4734c05004..89317f9f6049 100644 --- a/src/libnftables.c +++ b/src/libnftables.c @@ -807,8 +807,7 @@ int nft_run_cmd_from_filename(struct nft_ctx *nft, const char *filename) if (!strcmp(filename, "-")) filename = "/dev/stdin"; - if (!strcmp(filename, "/dev/stdin") && - !nft_output_json(&nft->output)) + if (!strcmp(filename, "/dev/stdin")) nft->stdin_buf = stdin_to_buffer(); if (!nft->stdin_buf && --iahYZQSa/7dWjrSZ--