From mboxrd@z Thu Jan 1 00:00:00 1970 From: jalvarez Subject: Re: [PATCH libnftnl] examples: selective rule dumping Date: Thu, 21 Jul 2016 10:03:01 +0200 Message-ID: <579081B5.1000100@toulouse.viveris.com> References: <578F7E7A.5080901@toulouse.viveris.com> <20160720180523.GA30217@salvia> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252; format=flowed Content-Transfer-Encoding: 7bit Cc: netfilter-devel@vger.kernel.org To: Pablo Neira Ayuso Return-path: Received: from mail.toulouse.viveris.com ([212.99.125.10]:36661 "EHLO mailS.toulouse.viveris.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751364AbcGUIDF (ORCPT ); Thu, 21 Jul 2016 04:03:05 -0400 In-Reply-To: <20160720180523.GA30217@salvia> Sender: netfilter-devel-owner@vger.kernel.org List-ID: On 20/07/2016 20:05, Pablo Neira Ayuso wrote: > On Wed, Jul 20, 2016 at 03:36:58PM +0200, jalvarez wrote: >> Add example (based on nft-get-rule.c) to demonstrate selective rule dumping >> when table and / or chain attributes are set in a rule dump request. >> Used to test the changes made in "[PATCH nf-next] netfilter: nf_tables: >> allow to filter out rules by table and chain" >> (http://marc.info/?t=146237901200004&r=1&w=2). >> >> Signed-off-by: Josue Alvarez >> -- >> diff --git a/examples/Makefile.am b/examples/Makefile.am >> index e002d36..73450c2 100644 >> --- a/examples/Makefile.am >> +++ b/examples/Makefile.am >> @@ -13,6 +13,7 @@ check_PROGRAMS = nft-table-add \ >> nft-rule-parse-add \ >> nft-rule-del \ >> nft-rule-get \ >> + nft-rule-selective-get \ > Would you rework this to integrate these changes into nft-rule-get? > I'd suggest you make the invocation look like this below. > > Usage: nft-rule-get [] [] > > So table and chain must be specified at the same time to keep it > simple, it is less flexible than what we actually support but I think > this is fine for an example. > > Thanks. Here are the changes then. I didn't put it in nft-rule-get.c at first to avoid breaking the expected behavior of the example. -- diff --git a/examples/nft-rule-get.c b/examples/nft-rule-get.c index 54bee73..4a491af 100644 --- a/examples/nft-rule-get.c +++ b/examples/nft-rule-get.c @@ -46,17 +46,50 @@ err: return MNL_CB_OK; } +static struct nftnl_rule *setup_rule(uint8_t family, const char *table, + const char *chain, const char *handle) +{ + struct nftnl_rule *r = NULL; + uint8_t proto; + uint16_t dport; + uint64_t handle_num; + + r = nftnl_rule_alloc(); + if (r == NULL) { + perror("OOM"); + exit(EXIT_FAILURE); + } + + if (table != NULL) + nftnl_rule_set(r, NFTNL_RULE_TABLE, table); + + if (chain != NULL) + nftnl_rule_set(r, NFTNL_RULE_CHAIN, chain); + + nftnl_rule_set_u32(r, NFTNL_RULE_FAMILY, family); + + if (handle != NULL) { + handle_num = atoll(handle); + nftnl_rule_set_u64(r, NFTNL_RULE_POSITION, handle_num); + } + + return r; +} + + + int main(int argc, char *argv[]) { struct mnl_socket *nl; char buf[MNL_SOCKET_BUFFER_SIZE]; struct nlmsghdr *nlh; + const char *table = NULL, *chain = NULL; uint32_t portid, seq, type = NFTNL_OUTPUT_DEFAULT; - struct nftnl_rule *t = NULL; + struct nftnl_rule *t, *r = NULL; int ret, family; - if (argc < 2 || argc > 3) { - fprintf(stderr, "Usage: %s [xml|json]\n", + if (argc < 2 || argc > 5) { + fprintf(stderr, "Usage: %s [
] [xml|json]\n", argv[0]); exit(EXIT_FAILURE); } @@ -76,13 +109,20 @@ int main(int argc, char *argv[]) exit(EXIT_FAILURE); } - if (argc == 3) { - if (strcmp(argv[2], "xml") == 0) + /* [xml|json] specified */ + if (argc == 3 || argc == 5) { + if (strcmp(argv[argc - 1], "xml") == 0) type = NFTNL_OUTPUT_XML; - else if (strcmp(argv[2], "json") == 0) + else if (strcmp(argv[argc - 1], "json") == 0) type = NFTNL_OUTPUT_JSON; } + /* at least [
] specified */ + if (argc >= 4) { + table = argv[2]; + chain = argv[3]; + } + /* XXX requires table, chain and handle attributes for selective get */ t = nftnl_rule_alloc(); @@ -95,6 +135,10 @@ int main(int argc, char *argv[]) nlh = nftnl_rule_nlmsg_build_hdr(buf, NFT_MSG_GETRULE, family, NLM_F_DUMP, seq); + r = setup_rule(family, table, chain, NULL); + nftnl_rule_nlmsg_build_payload(nlh, r); + + nl = mnl_socket_open(NETLINK_NETFILTER); if (nl == NULL) { perror("mnl_socket_open");