libnftnl 1.2.6
nft-set-elem-get.c
1/*
2 * (C) 2012 by Pablo Neira Ayuso <pablo@netfilter.org>
3 *
4 * This program is free software; you can redistribute it and/or modify it
5 * under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
8 *
9 * This software has been sponsored by Sophos Astaro <http://www.sophos.com>
10 */
11
12#include <stdlib.h>
13#include <time.h>
14#include <string.h>
15#include <netinet/in.h>
16
17#include <linux/netfilter.h>
18#include <linux/netfilter/nf_tables.h>
19
20#include <libmnl/libmnl.h>
21#include <libnftnl/set.h>
22
23static int set_cb(const struct nlmsghdr *nlh, void *data)
24{
25 struct nftnl_set *t;
26 char buf[4096];
27 uint32_t *type = data;
28
29 t = nftnl_set_alloc();
30 if (t == NULL) {
31 perror("OOM");
32 goto err;
33 }
34
35 if (nftnl_set_elems_nlmsg_parse(nlh, t) < 0) {
36 perror("nftnl_set_nlmsg_parse");
37 goto err_free;
38 }
39
40 nftnl_set_snprintf(buf, sizeof(buf), t, *type, 0);
41 printf("%s\n", buf);
42
43err_free:
44 nftnl_set_free(t);
45err:
46 return MNL_CB_OK;
47}
48
49int main(int argc, char *argv[])
50{
51 struct mnl_socket *nl;
52 char buf[MNL_SOCKET_BUFFER_SIZE];
53 struct nlmsghdr *nlh;
54 uint32_t portid, seq, family;
55 uint32_t type = NFTNL_OUTPUT_DEFAULT;
56 struct nftnl_set *t = NULL;
57 int ret;
58
59 if (argc < 4 || argc > 5) {
60 fprintf(stderr, "%s <family> <table> <set>\n", argv[0]);
61 return EXIT_FAILURE;
62 }
63 t = nftnl_set_alloc();
64 if (t == NULL) {
65 perror("OOM");
66 exit(EXIT_FAILURE);
67 }
68 seq = time(NULL);
69 if (strcmp(argv[1], "ip") == 0)
70 family = NFPROTO_IPV4;
71 else if (strcmp(argv[1], "ip6") == 0)
72 family = NFPROTO_IPV6;
73 else if (strcmp(argv[1], "inet") == 0)
74 family = NFPROTO_INET;
75 else if (strcmp(argv[1], "bridge") == 0)
76 family = NFPROTO_BRIDGE;
77 else if (strcmp(argv[1], "arp") == 0)
78 family = NFPROTO_ARP;
79 else {
80 fprintf(stderr, "Unknown family: ip, ip6, inet, bridge, arp\n");
81 exit(EXIT_FAILURE);
82 }
83
84 nlh = nftnl_nlmsg_build_hdr(buf, NFT_MSG_GETSETELEM, family,
85 NLM_F_DUMP | NLM_F_ACK, seq);
86 nftnl_set_set_str(t, NFTNL_SET_NAME, argv[3]);
87 nftnl_set_set_str(t, NFTNL_SET_TABLE, argv[2]);
88 nftnl_set_elems_nlmsg_build_payload(nlh, t);
89 nftnl_set_free(t);
90
91 nl = mnl_socket_open(NETLINK_NETFILTER);
92 if (nl == NULL) {
93 perror("mnl_socket_open");
94 exit(EXIT_FAILURE);
95 }
96
97 if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
98 perror("mnl_socket_bind");
99 exit(EXIT_FAILURE);
100 }
101 portid = mnl_socket_get_portid(nl);
102
103 if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) {
104 perror("mnl_socket_send");
105 exit(EXIT_FAILURE);
106 }
107
108 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
109 while (ret > 0) {
110 ret = mnl_cb_run(buf, ret, seq, portid, set_cb, &type);
111 if (ret <= 0)
112 break;
113 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
114 }
115 if (ret == -1) {
116 perror("error");
117 exit(EXIT_FAILURE);
118 }
119 mnl_socket_close(nl);
120
121 return EXIT_SUCCESS;
122}