10 #include <netinet/in.h>
11 #include <netinet/ip.h>
12 #include <netinet/tcp.h>
13 #include <arpa/inet.h>
14 #include <sys/types.h>
15 #include <sys/socket.h>
18 #include <linux/netfilter.h>
19 #include <linux/netfilter/nfnetlink.h>
20 #include <linux/netfilter/nf_tables.h>
22 #include <libmnl/libmnl.h>
23 #include <libnftnl/rule.h>
24 #include <libnftnl/expr.h>
26 static uint16_t parse_family(
char *str,
const char *option)
28 if (strcmp(str,
"ip") == 0)
30 else if (strcmp(str,
"ip6") == 0)
32 else if (strcmp(str,
"inet") == 0)
34 else if (strcmp(str,
"arp") == 0)
36 fprintf(stderr,
"Unknown %s: ip, ip6, inet, arp\n", option);
40 static void add_ct_expect(
struct nftnl_rule *r,
const char *obj_name)
44 e = nftnl_expr_alloc(
"objref");
46 perror(
"expr objref oom");
49 nftnl_expr_set_str(e, NFTNL_EXPR_OBJREF_IMM_NAME, obj_name);
50 nftnl_expr_set_u32(e, NFTNL_EXPR_OBJREF_IMM_TYPE, NFT_OBJECT_CT_EXPECT);
52 nftnl_rule_add_expr(r, e);
55 static struct nftnl_rule *setup_rule(uint8_t family,
const char *table,
56 const char *chain,
const char *handle,
59 struct nftnl_rule *r = NULL;
62 r = nftnl_rule_alloc();
68 nftnl_rule_set_str(r, NFTNL_RULE_TABLE, table);
69 nftnl_rule_set_str(r, NFTNL_RULE_CHAIN, chain);
70 nftnl_rule_set_u32(r, NFTNL_RULE_FAMILY, family);
73 handle_num = atoll(handle);
74 nftnl_rule_set_u64(r, NFTNL_RULE_POSITION, handle_num);
77 add_ct_expect(r, obj_name);
82 int main(
int argc,
char *argv[])
84 char buf[MNL_SOCKET_BUFFER_SIZE];
85 struct mnl_nlmsg_batch *batch;
86 uint32_t seq = time(NULL);
87 struct mnl_socket *nl;
93 if (argc < 5 || argc > 6) {
95 "Usage: %s <family> <table> <chain> [<handle>] <name>\n",
99 family = parse_family(argv[1],
"family");
102 r = setup_rule(family, argv[2], argv[3], NULL, argv[4]);
104 r = setup_rule(family, argv[2], argv[3], argv[4], argv[5]);
106 nl = mnl_socket_open(NETLINK_NETFILTER);
108 perror(
"mnl_socket_open");
112 if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
113 perror(
"mnl_socket_bind");
117 batch = mnl_nlmsg_batch_start(buf,
sizeof(buf));
119 nftnl_batch_begin(mnl_nlmsg_batch_current(batch), seq++);
120 mnl_nlmsg_batch_next(batch);
122 nlh = nftnl_nlmsg_build_hdr(mnl_nlmsg_batch_current(batch),
124 nftnl_rule_get_u32(r, NFTNL_RULE_FAMILY),
125 NLM_F_APPEND | NLM_F_CREATE | NLM_F_ACK,
127 nftnl_rule_nlmsg_build_payload(nlh, r);
129 mnl_nlmsg_batch_next(batch);
131 nftnl_batch_end(mnl_nlmsg_batch_current(batch), seq++);
132 mnl_nlmsg_batch_next(batch);
134 ret = mnl_socket_sendto(nl, mnl_nlmsg_batch_head(batch),
135 mnl_nlmsg_batch_size(batch));
137 perror(
"mnl_socket_sendto");
141 mnl_nlmsg_batch_stop(batch);
143 ret = mnl_socket_recvfrom(nl, buf,
sizeof(buf));
145 perror(
"mnl_socket_recvfrom");
149 ret = mnl_cb_run(buf, ret, 0, mnl_socket_get_portid(nl), NULL, NULL);
151 perror(
"mnl_cb_run");
155 mnl_socket_close(nl);