nft-events.c
/*
* (C) 2012 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This software has been sponsored by Sophos Astaro <http://www.sophos.com>
*/
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <netinet/in.h>
#include <linux/netfilter/nfnetlink.h>
#include <linux/netfilter/nf_tables.h>
#include <libmnl/libmnl.h>
#include <libnftnl/table.h>
#include <libnftnl/chain.h>
#include <libnftnl/rule.h>
#include <libnftnl/set.h>
#include <libnftnl/gen.h>
#include <libnftnl/common.h>
static uint32_t event2flag(uint32_t event)
{
switch (event) {
case NFT_MSG_NEWTABLE:
case NFT_MSG_NEWCHAIN:
case NFT_MSG_NEWRULE:
case NFT_MSG_NEWSET:
case NFT_MSG_NEWSETELEM:
case NFT_MSG_NEWGEN:
return NFTNL_OF_EVENT_NEW;
case NFT_MSG_DELTABLE:
case NFT_MSG_DELCHAIN:
case NFT_MSG_DELRULE:
case NFT_MSG_DELSET:
case NFT_MSG_DELSETELEM:
return NFTNL_OF_EVENT_DEL;
}
return 0;
}
static int table_cb(const struct nlmsghdr *nlh, int event, int type)
{
struct nftnl_table *t;
t = nftnl_table_alloc();
if (t == NULL) {
perror("OOM");
goto err;
}
if (nftnl_table_nlmsg_parse(nlh, t) < 0) {
perror("nftnl_table_nlmsg_parse");
goto err_free;
}
nftnl_table_fprintf(stdout, t, type, event2flag(event));
fprintf(stdout, "\n");
err_free:
nftnl_table_free(t);
err:
return MNL_CB_OK;
}
static int rule_cb(const struct nlmsghdr *nlh, int event, int type)
{
struct nftnl_rule *t;
t = nftnl_rule_alloc();
if (t == NULL) {
perror("OOM");
goto err;
}
if (nftnl_rule_nlmsg_parse(nlh, t) < 0) {
perror("nftnl_rule_nlmsg_parse");
goto err_free;
}
nftnl_rule_fprintf(stdout, t, type, event2flag(event));
fprintf(stdout, "\n");
err_free:
nftnl_rule_free(t);
err:
return MNL_CB_OK;
}
static int chain_cb(const struct nlmsghdr *nlh, int event, int type)
{
struct nftnl_chain *t;
t = nftnl_chain_alloc();
if (t == NULL) {
perror("OOM");
goto err;
}
if (nftnl_chain_nlmsg_parse(nlh, t) < 0) {
perror("nftnl_chain_nlmsg_parse");
goto err_free;
}
nftnl_chain_fprintf(stdout, t, type, event2flag(event));
fprintf(stdout, "\n");
err_free:
nftnl_chain_free(t);
err:
return MNL_CB_OK;
}
static int set_cb(const struct nlmsghdr *nlh, int event, int type)
{
struct nftnl_set *t;
t = nftnl_set_alloc();
if (t == NULL) {
perror("OOM");
goto err;
}
if (nftnl_set_nlmsg_parse(nlh, t) < 0) {
perror("nftnl_set_nlmsg_parse");
goto err_free;
}
nftnl_set_fprintf(stdout, t, type, event2flag(event));
fprintf(stdout, "\n");
err_free:
nftnl_set_free(t);
err:
return MNL_CB_OK;
}
static int setelem_cb(const struct nlmsghdr *nlh, int event, int type)
{
struct nftnl_set *s;
s = nftnl_set_alloc();
if (s == NULL) {
perror("OOM");
goto err;
}
if (nftnl_set_elems_nlmsg_parse(nlh, s) < 0) {
perror("nftnl_set_nlmsg_parse");
goto err_free;
}
nftnl_set_fprintf(stdout, s, type, event2flag(event));
fprintf(stdout, "\n");
err_free:
nftnl_set_free(s);
err:
return MNL_CB_OK;
}
static int gen_cb(const struct nlmsghdr *nlh, int event, int type)
{
struct nftnl_gen *gen;
gen = nftnl_gen_alloc();
if (gen == NULL) {
perror("OOM");
goto err;
}
if (nftnl_gen_nlmsg_parse(nlh, gen) < 0) {
perror("nftnl_gen_parse");
goto err_free;
}
nftnl_gen_fprintf(stdout, gen, type, event2flag(event));
fprintf(stdout, "\n");
err_free:
nftnl_gen_free(gen);
err:
return MNL_CB_OK;
}
static int events_cb(const struct nlmsghdr *nlh, void *data)
{
int ret = MNL_CB_OK;
int event = NFNL_MSG_TYPE(nlh->nlmsg_type);
int type = *((int *)data);
switch(event) {
case NFT_MSG_NEWTABLE:
case NFT_MSG_DELTABLE:
ret = table_cb(nlh, event, type);
break;
case NFT_MSG_NEWCHAIN:
case NFT_MSG_DELCHAIN:
ret = chain_cb(nlh, event, type);
break;
case NFT_MSG_NEWRULE:
case NFT_MSG_DELRULE:
ret = rule_cb(nlh, event, type);
break;
case NFT_MSG_NEWSET:
case NFT_MSG_DELSET:
ret = set_cb(nlh, event, type);
break;
case NFT_MSG_NEWSETELEM:
case NFT_MSG_DELSETELEM:
ret = setelem_cb(nlh, event, type);
break;
case NFT_MSG_NEWGEN:
ret = gen_cb(nlh, event, type);
break;
}
return ret;
}
int main(int argc, char *argv[])
{
struct mnl_socket *nl;
char buf[MNL_SOCKET_BUFFER_SIZE];
int ret, type;
switch (argc) {
case 1:
type = NFTNL_OUTPUT_DEFAULT;
break;
default:
fprintf(stderr, "%s\n", argv[0]);
return EXIT_FAILURE;
}
nl = mnl_socket_open(NETLINK_NETFILTER);
if (nl == NULL) {
perror("mnl_socket_open");
exit(EXIT_FAILURE);
}
if (mnl_socket_bind(nl, (1 << (NFNLGRP_NFTABLES-1)), MNL_SOCKET_AUTOPID) < 0) {
perror("mnl_socket_bind");
exit(EXIT_FAILURE);
}
ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
while (ret > 0) {
ret = mnl_cb_run(buf, ret, 0, 0, events_cb, &type);
if (ret <= 0)
break;
ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
}
if (ret == -1) {
perror("error");
exit(EXIT_FAILURE);
}
mnl_socket_close(nl);
return EXIT_SUCCESS;
}
nftnl_chain
Definition: chain.c:32
nftnl_gen
Definition: gen.c:26
nftnl_table
Definition: table.c:28