libnftnl 1.2.9
nft-rule-del.c
1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * (C) 2012 by Pablo Neira Ayuso <pablo@netfilter.org>
4 *
5 * This software has been sponsored by Sophos Astaro <http://www.sophos.com>
6 */
7
8#include <stdlib.h>
9#include <time.h>
10#include <string.h>
11#include <stddef.h> /* for offsetof */
12#include <netinet/in.h>
13
14#include <linux/netfilter.h>
15#include <linux/netfilter/nf_tables.h>
16#include <linux/netfilter/nfnetlink.h>
17
18#include <libmnl/libmnl.h>
19#include <libnftnl/rule.h>
20
21int main(int argc, char *argv[])
22{
23 struct mnl_socket *nl;
24 char buf[MNL_SOCKET_BUFFER_SIZE];
25 struct nlmsghdr *nlh;
26 struct mnl_nlmsg_batch *batch;
27 uint32_t portid, seq;
28 struct nftnl_rule *r = NULL;
29 int ret, family;
30
31 if (argc < 4 || argc > 5) {
32 fprintf(stderr, "Usage: %s <family> <table> <chain> [<handle>]\n",
33 argv[0]);
34 exit(EXIT_FAILURE);
35 }
36
37 r = nftnl_rule_alloc();
38 if (r == NULL) {
39 perror("OOM");
40 exit(EXIT_FAILURE);
41 }
42
43 if (strcmp(argv[1], "ip") == 0)
44 family = NFPROTO_IPV4;
45 else if (strcmp(argv[1], "ip6") == 0)
46 family = NFPROTO_IPV6;
47 else if (strcmp(argv[1], "inet") == 0)
48 family = NFPROTO_INET;
49 else if (strcmp(argv[1], "bridge") == 0)
50 family = NFPROTO_BRIDGE;
51 else if (strcmp(argv[1], "arp") == 0)
52 family = NFPROTO_ARP;
53 else {
54 fprintf(stderr, "Unknown family: ip, ip6, inet, bridge, arp\n");
55 exit(EXIT_FAILURE);
56 }
57
58 seq = time(NULL);
59 nftnl_rule_set_str(r, NFTNL_RULE_TABLE, argv[2]);
60 nftnl_rule_set_str(r, NFTNL_RULE_CHAIN, argv[3]);
61
62 /* If no handle is specified, delete all rules in the chain */
63 if (argc == 5)
64 nftnl_rule_set_u64(r, NFTNL_RULE_HANDLE, atoi(argv[4]));
65
66 batch = mnl_nlmsg_batch_start(buf, sizeof(buf));
67
68 nftnl_batch_begin(mnl_nlmsg_batch_current(batch), seq++);
69 mnl_nlmsg_batch_next(batch);
70
71 nlh = nftnl_nlmsg_build_hdr(mnl_nlmsg_batch_current(batch),
72 NFT_MSG_DELRULE, family, NLM_F_ACK, seq++);
73 nftnl_rule_nlmsg_build_payload(nlh, r);
74 nftnl_rule_free(r);
75 mnl_nlmsg_batch_next(batch);
76
77 nftnl_batch_end(mnl_nlmsg_batch_current(batch), seq++);
78 mnl_nlmsg_batch_next(batch);
79
80 nl = mnl_socket_open(NETLINK_NETFILTER);
81 if (nl == NULL) {
82 perror("mnl_socket_open");
83 exit(EXIT_FAILURE);
84 }
85
86 if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
87 perror("mnl_socket_bind");
88 exit(EXIT_FAILURE);
89 }
90 portid = mnl_socket_get_portid(nl);
91
92 if (mnl_socket_sendto(nl, mnl_nlmsg_batch_head(batch),
93 mnl_nlmsg_batch_size(batch)) < 0) {
94 perror("mnl_socket_send");
95 exit(EXIT_FAILURE);
96 }
97
98 mnl_nlmsg_batch_stop(batch);
99
100 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
101 while (ret > 0) {
102 ret = mnl_cb_run(buf, ret, 0, portid, NULL, NULL);
103 if (ret <= 0)
104 break;
105 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
106 }
107 if (ret == -1) {
108 perror("error");
109 exit(EXIT_FAILURE);
110 }
111 mnl_socket_close(nl);
112
113 return EXIT_SUCCESS;
114}