libnftnl 1.2.6
nft-ct-helper-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
13#include <stdlib.h>
14#include <time.h>
15#include <string.h>
16#include <netinet/in.h>
17
18#include <linux/netfilter.h>
19#include <linux/netfilter/nf_tables.h>
20
21#include <libmnl/libmnl.h>
22#include <libnftnl/object.h>
23
24static int obj_cb(const struct nlmsghdr *nlh, void *data)
25{
26 struct nftnl_obj *t;
27 char buf[4096];
28 uint32_t *type = data;
29
30 t = nftnl_obj_alloc();
31 if (t == NULL) {
32 perror("OOM");
33 goto err;
34 }
35
36 if (nftnl_obj_nlmsg_parse(nlh, t) < 0) {
37 perror("nftnl_obj_nlmsg_parse");
38 goto err_free;
39 }
40
41 nftnl_obj_snprintf(buf, sizeof(buf), t, *type, 0);
42 printf("%s\n", buf);
43
44err_free:
45 nftnl_obj_free(t);
46err:
47 return MNL_CB_OK;
48}
49
50int main(int argc, char *argv[])
51{
52 struct mnl_socket *nl;
53 char buf[MNL_SOCKET_BUFFER_SIZE];
54 struct nlmsghdr *nlh;
55 uint32_t portid, seq, family;
56 struct nftnl_obj *t = NULL;
57 int ret;
58 uint32_t type = NFTNL_OUTPUT_DEFAULT;
59
60 if (argc < 3 || argc > 5) {
61 fprintf(stderr, "%s <family> <table> [<obj>]\n",
62 argv[0]);
63 return EXIT_FAILURE;
64 }
65
66 if (strcmp(argv[1], "ip") == 0)
67 family = NFPROTO_IPV4;
68 else if (strcmp(argv[1], "ip6") == 0)
69 family = NFPROTO_IPV6;
70 else if (strcmp(argv[1], "inet") == 0)
71 family = NFPROTO_INET;
72 else if (strcmp(argv[1], "unspec") == 0)
73 family = NFPROTO_UNSPEC;
74 else {
75 fprintf(stderr, "Unknown family: ip, ip6, inet, unspec");
76 exit(EXIT_FAILURE);
77 }
78
79 if (argc == 3 || argc == 4) {
80 t = nftnl_obj_alloc();
81 if (t == NULL) {
82 perror("OOM");
83 exit(EXIT_FAILURE);
84 }
85 }
86
87 seq = time(NULL);
88 nftnl_obj_set_u32(t, NFTNL_OBJ_TYPE, NFT_OBJECT_CT_HELPER);
89 if (argc < 4) {
90 nlh = nftnl_nlmsg_build_hdr(buf, NFT_MSG_GETOBJ, family,
91 NLM_F_DUMP, seq);
92 if (argc == 3) {
93 nftnl_obj_set_str(t, NFTNL_OBJ_TABLE, argv[2]);
94 nftnl_obj_nlmsg_build_payload(nlh, t);
95 nftnl_obj_free(t);
96 }
97 } else {
98 nftnl_obj_set_str(t, NFTNL_OBJ_TABLE, argv[2]);
99 nftnl_obj_set_str(t, NFTNL_OBJ_NAME, argv[3]);
100
101 nlh = nftnl_nlmsg_build_hdr(buf, NFT_MSG_GETOBJ, family,
102 NLM_F_ACK, seq);
103 nftnl_obj_nlmsg_build_payload(nlh, t);
104 nftnl_obj_free(t);
105 }
106
107 nl = mnl_socket_open(NETLINK_NETFILTER);
108 if (nl == NULL) {
109 perror("mnl_socket_open");
110 exit(EXIT_FAILURE);
111 }
112
113 if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
114 perror("mnl_socket_bind");
115 exit(EXIT_FAILURE);
116 }
117 portid = mnl_socket_get_portid(nl);
118
119 if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) {
120 perror("mnl_socket_send");
121 exit(EXIT_FAILURE);
122 }
123
124 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
125 while (ret > 0) {
126 ret = mnl_cb_run(buf, ret, seq, portid, obj_cb, &type);
127 if (ret <= 0)
128 break;
129 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
130 }
131 if (ret == -1) {
132 perror("error");
133 exit(EXIT_FAILURE);
134 }
135 mnl_socket_close(nl);
136
137 return EXIT_SUCCESS;
138}