/usr/share/doc/libnftnl-dev/examples/nft-rule-get.c is in libnftnl-dev 1.0.7-1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 | /*
* (C) 2012 by Pablo Neira Ayuso <pablo@netfilter.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This software has been sponsored by Sophos Astaro <http://www.sophos.com>
*/
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <netinet/in.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <libmnl/libmnl.h>
#include <libnftnl/rule.h>
static int table_cb(const struct nlmsghdr *nlh, void *data)
{
struct nftnl_rule *t;
char buf[4096];
uint32_t *type = data;
t = nftnl_rule_alloc();
if (t == NULL) {
perror("OOM");
goto err;
}
if (nftnl_rule_nlmsg_parse(nlh, t) < 0) {
perror("nftnl_rule_nlmsg_parse");
goto err_free;
}
nftnl_rule_snprintf(buf, sizeof(buf), t, *type, 0);
printf("%s\n", buf);
err_free:
nftnl_rule_free(t);
err:
return MNL_CB_OK;
}
static struct nftnl_rule *setup_rule(uint8_t family, const char *table,
const char *chain, const char *handle)
{
struct nftnl_rule *r;
uint64_t handle_num;
r = nftnl_rule_alloc();
if (r == NULL)
return NULL;
if (table != NULL)
nftnl_rule_set_str(r, NFTNL_RULE_TABLE, table);
if (chain != NULL)
nftnl_rule_set_str(r, NFTNL_RULE_CHAIN, chain);
nftnl_rule_set_u32(r, NFTNL_RULE_FAMILY, family);
if (handle != NULL) {
handle_num = atoll(handle);
nftnl_rule_set_u64(r, NFTNL_RULE_POSITION, handle_num);
}
return r;
}
int main(int argc, char *argv[])
{
struct mnl_socket *nl;
char buf[MNL_SOCKET_BUFFER_SIZE];
struct nlmsghdr *nlh;
uint32_t portid, seq, type = NFTNL_OUTPUT_DEFAULT;
const char *table = NULL, *chain = NULL;
struct nftnl_rule *r;
int ret, family;
if (argc < 2 || argc > 5) {
fprintf(stderr, "Usage: %s <family> [<table> <chain>] [json]\n",
argv[0]);
exit(EXIT_FAILURE);
}
if (strcmp(argv[1], "ip") == 0)
family = NFPROTO_IPV4;
else if (strcmp(argv[1], "ip6") == 0)
family = NFPROTO_IPV6;
else if (strcmp(argv[1], "bridge") == 0)
family = NFPROTO_BRIDGE;
else if (strcmp(argv[1], "arp") == 0)
family = NFPROTO_ARP;
else if (strcmp(argv[1], "unspec") == 0)
family = NFPROTO_UNSPEC;
else {
fprintf(stderr, "Unknown family: ip, ip6, bridge, arp, unspec\n");
exit(EXIT_FAILURE);
}
/* json specified */
if (argc == 3 || argc == 5) {
if (strcmp(argv[argc - 1], "json") == 0)
type = NFTNL_OUTPUT_JSON;
}
/* at least [<table> <chain>] specified */
if (argc >= 4) {
table = argv[2];
chain = argv[3];
}
seq = time(NULL);
nlh = nftnl_rule_nlmsg_build_hdr(buf, NFT_MSG_GETRULE, family,
NLM_F_DUMP, seq);
r = setup_rule(family, table, chain, NULL);
if (!r) {
perror("setup_rule");
exit(EXIT_FAILURE);
}
nftnl_rule_nlmsg_build_payload(nlh, r);
nl = mnl_socket_open(NETLINK_NETFILTER);
if (nl == NULL) {
perror("mnl_socket_open");
exit(EXIT_FAILURE);
}
if (mnl_socket_bind(nl, 0, MNL_SOCKET_AUTOPID) < 0) {
perror("mnl_socket_bind");
exit(EXIT_FAILURE);
}
portid = mnl_socket_get_portid(nl);
if (mnl_socket_sendto(nl, nlh, nlh->nlmsg_len) < 0) {
perror("mnl_socket_send");
exit(EXIT_FAILURE);
}
ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
while (ret > 0) {
ret = mnl_cb_run(buf, ret, seq, portid, table_cb, &type);
if (ret <= 0)
break;
ret = mnl_socket_recvfrom(nl, buf, sizeof(buf));
}
if (ret == -1) {
perror("error");
exit(EXIT_FAILURE);
}
mnl_socket_close(nl);
return EXIT_SUCCESS;
}
|