summaryrefslogtreecommitdiffstats
path: root/examples/nft-chain-del.c
blob: 29953d7ea905286d503363282a00684cde63a0c7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
/*
 * (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.h>
#include <linux/netfilter/nf_tables.h>

#include <libmnl/libmnl.h>
#include <libnftnl/chain.h>

static struct nftnl_chain *chain_del_parse(int argc, char *argv[])
{
	struct nftnl_chain *t;

	t = nftnl_chain_alloc();
	if (t == NULL) {
		perror("OOM");
		return NULL;
	}

	nftnl_chain_attr_set(t, NFTNL_CHAIN_TABLE, argv[2]);
	nftnl_chain_attr_set(t, NFTNL_CHAIN_NAME, argv[3]);

	return t;
}

int main(int argc, char *argv[])
{
	struct mnl_socket *nl;
	struct mnl_nlmsg_batch *batch;
	char buf[MNL_SOCKET_BUFFER_SIZE];
	struct nlmsghdr *nlh;
	uint32_t portid, seq, chain_seq;
	struct nftnl_chain *t;
	int ret, family, batching;

	if (argc != 4) {
		fprintf(stderr, "Usage: %s <family> <table> <chain>\n",
			argv[0]);
		exit(EXIT_FAILURE);
	}

	if (strcmp(argv[1], "ip") == 0)
		family = NFPROTO_IPV4;
	else if (strcmp(argv[1], "ip6") == 0)
		family = NFPROTO_IPV6;
	else if (strcmp(argv[1], "bridge") == 0)
		family = NFPROTO_BRIDGE;
	else if (strcmp(argv[1], "arp") == 0)
		family = NFPROTO_ARP;
	else {
		fprintf(stderr, "Unknown family: ip, ip6, bridge, arp\n");
		exit(EXIT_FAILURE);
	}

	t = chain_del_parse(argc, argv);
	if (t == NULL)
		exit(EXIT_FAILURE);

	batching = nftnl_batch_is_supported();
	if (batching < 0) {
		perror("cannot talk to nfnetlink");
		exit(EXIT_FAILURE);
	}

	seq = time(NULL);
	batch = mnl_nlmsg_batch_start(buf, sizeof(buf));

	if (batching) {
		nftnl_batch_begin(mnl_nlmsg_batch_current(batch), seq++);
		mnl_nlmsg_batch_next(batch);
	}

	chain_seq = seq;
	nlh = nftnl_chain_nlmsg_build_hdr(mnl_nlmsg_batch_current(batch),
					NFT_MSG_DELCHAIN, family,
					NLM_F_ACK, seq++);
	nftnl_chain_nlmsg_build_payload(nlh, t);
	nftnl_chain_free(t);
	mnl_nlmsg_batch_next(batch);

	if (batching) {
		nftnl_batch_end(mnl_nlmsg_batch_current(batch), seq++);
		mnl_nlmsg_batch_next(batch);
	}

	nl = mnl_socket_open(NETLINK_NETFILTER);
	if (nl == NULL) {
		perror("mnl_socket_open");
		exit(EXIT_FAILURE);
	}

	if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
		perror("mnl_socket_bind");
		exit(EXIT_FAILURE);
	}
	portid = mnl_socket_get_portid(nl);

	if (mnl_socket_sendto(nl, mnl_nlmsg_batch_head(batch),
			      mnl_nlmsg_batch_size(batch)) < 0) {
		perror("mnl_socket_send");
		exit(EXIT_FAILURE);
	}

	ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
	while (ret > 0) {
		ret = mnl_cb_run(buf, ret, chain_seq, portid, NULL, NULL);
		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;
}