libnftnl 1.2.9
nft-compat-get.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 <netinet/in.h>
12
13#include <linux/netfilter/nfnetlink.h>
14#include <linux/netfilter/nf_tables_compat.h>
15
16#include <libmnl/libmnl.h>
17
18static int data_attr_cb(const struct nlattr *attr, void *data)
19{
20 const struct nlattr **tb = data;
21 int type = mnl_attr_get_type(attr);
22
23 if (mnl_attr_type_valid(attr, NFTA_COMPAT_MAX) < 0)
24 return MNL_CB_OK;
25
26 switch(type) {
27 case NFTA_COMPAT_NAME:
28 if (mnl_attr_validate(attr, MNL_TYPE_STRING) < 0) {
29 perror("mnl_attr_validate");
30 return MNL_CB_ERROR;
31 }
32 break;
33 case NFTA_COMPAT_REV:
34 case NFTA_COMPAT_TYPE:
35 if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0) {
36 perror("mnl_attr_validate");
37 return MNL_CB_ERROR;
38 }
39 break;
40 }
41 tb[type] = attr;
42 return MNL_CB_OK;
43}
44
45static int cb(const struct nlmsghdr *nlh, void *data)
46{
47 struct nlattr *tb[NFTA_COMPAT_MAX+1] = {};
48 struct nfgenmsg *nfg = mnl_nlmsg_get_payload(nlh);
49
50 if (mnl_attr_parse(nlh, sizeof(*nfg), data_attr_cb, tb) < 0)
51 return MNL_CB_ERROR;
52
53 if (tb[NFTA_COMPAT_NAME])
54 printf("name=%s ", mnl_attr_get_str(tb[NFTA_COMPAT_NAME]));
55 if (tb[NFTA_COMPAT_REV])
56 printf("rev=%d ", ntohl(mnl_attr_get_u32(tb[NFTA_COMPAT_REV])));
57 if (tb[NFTA_COMPAT_TYPE])
58 printf("type=%d ", ntohl(mnl_attr_get_u32(tb[NFTA_COMPAT_REV])));
59
60 printf("\n");
61
62 return MNL_CB_OK;
63}
64
65int main(int argc, char *argv[])
66{
67 struct mnl_socket *nl;
68 char buf[MNL_SOCKET_BUFFER_SIZE];
69 struct nlmsghdr *nlh;
70 uint32_t portid, seq, rev, type;
71 int ret;
72
73 if (argc != 4) {
74 fprintf(stderr, "Usage: %s <extension_name> <type> <rev>\n",
75 argv[0]);
76 return EXIT_FAILURE;
77 }
78
79 if (strcmp(argv[2], "target") == 0)
80 type = 1;
81 else if (strcmp(argv[2], "match") == 0)
82 type = 0;
83 else {
84 fprintf(stderr, "type should be `target' or `match'\n");
85 return EXIT_FAILURE;
86 }
87 rev = atoi(argv[3]);
88
89 nlh = mnl_nlmsg_put_header(buf);
90 nlh->nlmsg_type = (NFNL_SUBSYS_NFT_COMPAT << 8) | NFNL_MSG_COMPAT_GET;
91 nlh->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK;
92 nlh->nlmsg_seq = seq = time(NULL);
93
94 struct nfgenmsg *nfg = mnl_nlmsg_put_extra_header(nlh, sizeof(*nfg));
95 nfg->nfgen_family = AF_INET;
96 nfg->version = NFNETLINK_V0;
97 nfg->res_id = 0;
98
99 mnl_attr_put_strz(nlh, NFTA_COMPAT_NAME, argv[1]);
100 mnl_attr_put_u32(nlh, NFTA_COMPAT_REV, htonl(rev));
101 mnl_attr_put_u32(nlh, NFTA_COMPAT_TYPE, htonl(type));
102
103 printf("requesting `%s' rev=%d type=%d\n", argv[1], rev, type);
104
105 nl = mnl_socket_open(NETLINK_NETFILTER);
106 if (nl == NULL) {
107 perror("mnl_socket_open");
108 exit(EXIT_FAILURE);
109 }
110
111 if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
112 perror("mnl_socket_bind");
113 exit(EXIT_FAILURE);
114 }
115 portid = mnl_socket_get_portid(nl);
116
117 if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) {
118 perror("mnl_socket_send");
119 exit(EXIT_FAILURE);
120 }
121
122 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
123 while (ret > 0) {
124 ret = mnl_cb_run(buf, ret, seq, portid, cb, NULL);
125 if (ret <= 0)
126 break;
127 ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
128 }
129 if (ret == -1) {
130 perror("error");
131 exit(EXIT_FAILURE);
132 }
133 mnl_socket_close(nl);
134
135 return EXIT_SUCCESS;
136}