libnftnl  1.2.9
nft-ct-expectation-del.c
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * (C) 2019 by Stéphane Veyret <sveyret@gmail.com>
4  */
5 
6 #include <stdlib.h>
7 #include <time.h>
8 #include <string.h>
9 #include <netinet/in.h>
10 
11 #include <linux/netfilter.h>
12 #include <linux/netfilter/nf_tables.h>
13 
14 #include <libmnl/libmnl.h>
15 #include <libnftnl/object.h>
16 
17 static uint16_t parse_family(char *str, const char *option)
18 {
19  if (strcmp(str, "ip") == 0)
20  return NFPROTO_IPV4;
21  else if (strcmp(str, "ip6") == 0)
22  return NFPROTO_IPV6;
23  else if (strcmp(str, "inet") == 0)
24  return NFPROTO_INET;
25  else if (strcmp(str, "arp") == 0)
26  return NFPROTO_INET;
27  fprintf(stderr, "Unknown %s: ip, ip6, inet, arp\n", option);
28  exit(EXIT_FAILURE);
29 }
30 
31 static struct nftnl_obj *obj_parse(int argc, char *argv[])
32 {
33  struct nftnl_obj *t;
34  uint16_t family;
35 
36  t = nftnl_obj_alloc();
37  if (t == NULL) {
38  perror("OOM");
39  return NULL;
40  }
41 
42  family = parse_family(argv[1], "family");
43  nftnl_obj_set_u32(t, NFTNL_OBJ_FAMILY, family);
44  nftnl_obj_set_u32(t, NFTNL_OBJ_TYPE, NFT_OBJECT_CT_EXPECT);
45  nftnl_obj_set_str(t, NFTNL_OBJ_TABLE, argv[2]);
46  nftnl_obj_set_str(t, NFTNL_OBJ_NAME, argv[3]);
47 
48  return t;
49 }
50 
51 int main(int argc, char *argv[])
52 {
53  struct mnl_socket *nl;
54  char buf[MNL_SOCKET_BUFFER_SIZE];
55  struct nlmsghdr *nlh;
56  uint32_t portid, seq, obj_seq, family;
57  struct nftnl_obj *t;
58  struct mnl_nlmsg_batch *batch;
59  int ret;
60 
61  if (argc != 4) {
62  fprintf(stderr, "%s <family> <table> <name>\n", argv[0]);
63  exit(EXIT_FAILURE);
64  }
65 
66  t = obj_parse(argc, argv);
67  if (t == NULL)
68  exit(EXIT_FAILURE);
69 
70  seq = time(NULL);
71  batch = mnl_nlmsg_batch_start(buf, sizeof(buf));
72 
73  nftnl_batch_begin(mnl_nlmsg_batch_current(batch), seq++);
74  mnl_nlmsg_batch_next(batch);
75 
76  obj_seq = seq;
77  family = nftnl_obj_get_u32(t, NFTNL_OBJ_FAMILY);
78  nlh = nftnl_nlmsg_build_hdr(mnl_nlmsg_batch_current(batch),
79  NFT_MSG_DELOBJ, family, NLM_F_ACK,
80  seq++);
81  nftnl_obj_nlmsg_build_payload(nlh, t);
82  mnl_nlmsg_batch_next(batch);
83  nftnl_obj_free(t);
84 
85  nftnl_batch_end(mnl_nlmsg_batch_current(batch), seq++);
86  mnl_nlmsg_batch_next(batch);
87 
88  nl = mnl_socket_open(NETLINK_NETFILTER);
89  if (nl == NULL) {
90  perror("mnl_socket_open");
91  exit(EXIT_FAILURE);
92  }
93 
94  if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
95  perror("mnl_socket_bind");
96  exit(EXIT_FAILURE);
97  }
98  portid = mnl_socket_get_portid(nl);
99 
100  if (mnl_socket_sendto(nl, mnl_nlmsg_batch_head(batch),
101  mnl_nlmsg_batch_size(batch)) < 0) {
102  perror("mnl_socket_send");
103  exit(EXIT_FAILURE);
104  }
105 
106  mnl_nlmsg_batch_stop(batch);
107 
108  ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
109  while (ret > 0) {
110  ret = mnl_cb_run(buf, ret, obj_seq, portid, NULL, NULL);
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 }