libnftnl 1.2.6
nft-obj-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/object.h>
22
23static int obj_cb(const struct nlmsghdr *nlh, void *data)
24{
25 struct nftnl_obj *t;
26 char buf[4096];
27 uint32_t *type = data;
28
29 t = nftnl_obj_alloc();
30 if (t == NULL) {
31 perror("OOM");
32 goto err;
33 }
34
35 if (nftnl_obj_nlmsg_parse(nlh, t) < 0) {
36 perror("nftnl_obj_nlmsg_parse");
37 goto err_free;
38 }
39
40 nftnl_obj_snprintf(buf, sizeof(buf), t, *type, 0);
41 printf("%s\n", buf);
42
43err_free:
44 nftnl_obj_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 struct nftnl_obj *t = NULL;
56 int ret;
57 uint32_t type = NFTNL_OUTPUT_DEFAULT;
58
59 if (argc < 2 || argc > 5) {
60 fprintf(stderr, "%s <family> <table> [<obj>]\n", argv[0]);
61 return EXIT_FAILURE;
62 }
63
64 if (strcmp(argv[1], "ip") == 0)
65 family = NFPROTO_IPV4;
66 else if (strcmp(argv[1], "ip6") == 0)
67 family = NFPROTO_IPV6;
68 else if (strcmp(argv[1], "inet") == 0)
69 family = NFPROTO_INET;
70 else if (strcmp(argv[1], "bridge") == 0)
71 family = NFPROTO_BRIDGE;
72 else if (strcmp(argv[1], "arp") == 0)
73 family = NFPROTO_ARP;
74 else if (strcmp(argv[1], "unspec") == 0)
75 family = NFPROTO_UNSPEC;
76 else {
77 fprintf(stderr, "Unknown family: ip, ip6, inet, bridge, arp, unspec\n");
78 exit(EXIT_FAILURE);
79 }
80
81 if (argc == 3 || argc == 4) {
82 t = nftnl_obj_alloc();
83 if (t == NULL) {
84 perror("OOM");
85 exit(EXIT_FAILURE);
86 }
87 }
88
89 seq = time(NULL);
90 if (argc < 4) {
91 nlh = nftnl_nlmsg_build_hdr(buf, NFT_MSG_GETOBJ, family,
92 NLM_F_DUMP, seq);
93 if (argc == 3) {
94 nftnl_obj_set_str(t, NFTNL_OBJ_TABLE, argv[2]);
95 nftnl_obj_nlmsg_build_payload(nlh, t);
96 nftnl_obj_free(t);
97 }
98 } else {
99 nftnl_obj_set_str(t, NFTNL_OBJ_TABLE, argv[2]);
100 nftnl_obj_set_str(t, NFTNL_OBJ_NAME, argv[3]);
101 nftnl_obj_set_u32(t, NFTNL_OBJ_TYPE, NFT_OBJECT_COUNTER);
102
103 nlh = nftnl_nlmsg_build_hdr(buf, NFT_MSG_GETOBJ, family,
104 NLM_F_ACK, seq);
105 nftnl_obj_nlmsg_build_payload(nlh, t);
106 nftnl_obj_free(t);
107 }
108
109 nl = mnl_socket_open(NETLINK_NETFILTER);
110 if (nl == NULL) {
111 perror("mnl_socket_open");
112 exit(EXIT_FAILURE);
113 }
114
115 if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
116 perror("mnl_socket_bind");
117 exit(EXIT_FAILURE);
118 }
119 portid = mnl_socket_get_portid(nl);
120
121 if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) {
122 perror("mnl_socket_send");
123 exit(EXIT_FAILURE);
124 }
125
126 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
127 while (ret > 0) {
128 ret = mnl_cb_run(buf, ret, seq, portid, obj_cb, &type);
129 if (ret <= 0)
130 break;
131 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
132 }
133 if (ret == -1) {
134 perror("error");
135 exit(EXIT_FAILURE);
136 }
137 mnl_socket_close(nl);
138
139 return EXIT_SUCCESS;
140}