libnftnl  1.1.9
nft-flowtable-add.c
1 #include <stdlib.h>
2 #include <time.h>
3 #include <string.h>
4 #include <netinet/in.h>
5 
6 #include <linux/netfilter.h>
7 #include <linux/netfilter/nf_tables.h>
8 
9 #include <libmnl/libmnl.h>
10 #include <libnftnl/flowtable.h>
11 
12 static struct nftnl_flowtable *flowtable_add_parse(int argc, char *argv[])
13 {
14  const char *dev_array[] = { "eth0", "tap0", NULL };
15  struct nftnl_flowtable *t;
16  int hooknum = 0;
17 
18  if (strcmp(argv[4], "ingress") == 0)
19  hooknum = NF_NETDEV_INGRESS;
20  else {
21  fprintf(stderr, "Unknown hook: %s\n", argv[4]);
22  return NULL;
23  }
24 
25  t = nftnl_flowtable_alloc();
26  if (t == NULL) {
27  perror("OOM");
28  return NULL;
29  }
30  nftnl_flowtable_set_str(t, NFTNL_FLOWTABLE_TABLE, argv[2]);
31  nftnl_flowtable_set_str(t, NFTNL_FLOWTABLE_NAME, argv[3]);
32  if (argc == 6) {
33  nftnl_flowtable_set_u32(t, NFTNL_FLOWTABLE_HOOKNUM, hooknum);
34  nftnl_flowtable_set_u32(t, NFTNL_FLOWTABLE_PRIO, atoi(argv[5]));
35  }
36  nftnl_flowtable_set_data(t, NFTNL_FLOWTABLE_DEVICES, dev_array, 0);
37 
38  return t;
39 }
40 
41 int main(int argc, char *argv[])
42 {
43  struct mnl_socket *nl;
44  char buf[MNL_SOCKET_BUFFER_SIZE];
45  struct nlmsghdr *nlh;
46  uint32_t portid, seq, flowtable_seq;
47  int ret, family;
48  struct nftnl_flowtable *t;
49  struct mnl_nlmsg_batch *batch;
50  int batching;
51 
52  if (argc != 6) {
53  fprintf(stderr, "Usage: %s <family> <table> <name> <hook> <prio>\n",
54  argv[0]);
55  exit(EXIT_FAILURE);
56  }
57 
58  if (strcmp(argv[1], "ip") == 0)
59  family = NFPROTO_IPV4;
60  else if (strcmp(argv[1], "ip6") == 0)
61  family = NFPROTO_IPV6;
62  else if (strcmp(argv[1], "inet") == 0)
63  family = NFPROTO_INET;
64  else if (strcmp(argv[1], "bridge") == 0)
65  family = NFPROTO_BRIDGE;
66  else if (strcmp(argv[1], "arp") == 0)
67  family = NFPROTO_ARP;
68  else {
69  fprintf(stderr, "Unknown family: ip, ip6, inet, bridge, arp\n");
70  exit(EXIT_FAILURE);
71  }
72 
73  t = flowtable_add_parse(argc, argv);
74  if (t == NULL)
75  exit(EXIT_FAILURE);
76 
77  batching = nftnl_batch_is_supported();
78  if (batching < 0) {
79  perror("cannot talk to nfnetlink");
80  exit(EXIT_FAILURE);
81  }
82 
83  seq = time(NULL);
84  batch = mnl_nlmsg_batch_start(buf, sizeof(buf));
85 
86  if (batching) {
87  nftnl_batch_begin(mnl_nlmsg_batch_current(batch), seq++);
88  mnl_nlmsg_batch_next(batch);
89  }
90 
91  flowtable_seq = seq;
92  nlh = nftnl_flowtable_nlmsg_build_hdr(mnl_nlmsg_batch_current(batch),
93  NFT_MSG_NEWFLOWTABLE, family,
94  NLM_F_CREATE|NLM_F_ACK, seq++);
95  nftnl_flowtable_nlmsg_build_payload(nlh, t);
96  nftnl_flowtable_free(t);
97  mnl_nlmsg_batch_next(batch);
98 
99  if (batching) {
100  nftnl_batch_end(mnl_nlmsg_batch_current(batch), seq++);
101  mnl_nlmsg_batch_next(batch);
102  }
103 
104  nl = mnl_socket_open(NETLINK_NETFILTER);
105  if (nl == NULL) {
106  perror("mnl_socket_open");
107  exit(EXIT_FAILURE);
108  }
109 
110  if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
111  perror("mnl_socket_bind");
112  exit(EXIT_FAILURE);
113  }
114  portid = mnl_socket_get_portid(nl);
115 
116  if (mnl_socket_sendto(nl, mnl_nlmsg_batch_head(batch),
117  mnl_nlmsg_batch_size(batch)) < 0) {
118  perror("mnl_socket_send");
119  exit(EXIT_FAILURE);
120  }
121 
122  mnl_nlmsg_batch_stop(batch);
123 
124  ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
125  while (ret > 0) {
126  ret = mnl_cb_run(buf, ret, flowtable_seq, portid, NULL, NULL);
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 }