nft-ruleset-get.c
/*
* Copyright (c) 2013 Arturo Borrero Gonzalez <arturo@debian.org>
*
* based on previous code from:
*
* Copyright (c) 2013 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 version 2 as
* published by the Free Software Foundation.
*
*/
#include <stdlib.h>
#include <time.h>
#include <string.h>
#include <netinet/in.h>
#include <errno.h>
#include <linux/netfilter.h>
#include <linux/netfilter/nf_tables.h>
#include <libmnl/libmnl.h>
#include <libnftnl/common.h>
#include <libnftnl/ruleset.h>
#include <libnftnl/table.h>
#include <libnftnl/chain.h>
#include <libnftnl/set.h>
#include <libnftnl/rule.h>
static int seq;
static void memory_allocation_error(void)
{
perror("OOM");
exit(EXIT_FAILURE);
}
static int
mnl_talk(struct mnl_socket *nf_sock, const void *data, unsigned int len,
int (*cb)(const struct nlmsghdr *nlh, void *data), void *cb_data)
{
char buf[MNL_SOCKET_BUFFER_SIZE];
uint32_t portid = mnl_socket_get_portid(nf_sock);
int ret;
if (mnl_socket_sendto(nf_sock, data, len) < 0)
return -1;
ret = mnl_socket_recvfrom(nf_sock, buf, sizeof(buf));
while (ret > 0) {
ret = mnl_cb_run(buf, ret, seq, portid, cb, cb_data);
if (ret <= 0)
goto out;
ret = mnl_socket_recvfrom(nf_sock, buf, sizeof(buf));
}
out:
if (ret < 0 && errno == EAGAIN)
return 0;
return ret;
}
/*
* Rule
*/
static int rule_cb(const struct nlmsghdr *nlh, void *data)
{
struct nftnl_rule_list *nlr_list = data;
struct nftnl_rule *r;
r = nftnl_rule_alloc();
if (r == NULL)
memory_allocation_error();
if (nftnl_rule_nlmsg_parse(nlh, r) < 0)
goto err_free;
nftnl_rule_list_add_tail(r, nlr_list);
return MNL_CB_OK;
err_free:
nftnl_rule_free(r);
return MNL_CB_OK;
}
static struct nftnl_rule_list *mnl_rule_dump(struct mnl_socket *nf_sock,
int family)
{
char buf[MNL_SOCKET_BUFFER_SIZE];
struct nlmsghdr *nlh;
struct nftnl_rule_list *nlr_list;
int ret;
nlr_list = nftnl_rule_list_alloc();
if (nlr_list == NULL)
memory_allocation_error();
nlh = nftnl_rule_nlmsg_build_hdr(buf, NFT_MSG_GETRULE, family,
NLM_F_DUMP, seq);
ret = mnl_talk(nf_sock, nlh, nlh->nlmsg_len, rule_cb, nlr_list);
if (ret < 0)
goto err;
return nlr_list;
err:
nftnl_rule_list_free(nlr_list);
return NULL;
}
/*
* Chain
*/
static int chain_cb(const struct nlmsghdr *nlh, void *data)
{
struct nftnl_chain_list *nlc_list = data;
struct nftnl_chain *c;
c = nftnl_chain_alloc();
if (c == NULL)
memory_allocation_error();
if (nftnl_chain_nlmsg_parse(nlh, c) < 0)
goto err_free;
nftnl_chain_list_add_tail(c, nlc_list);
return MNL_CB_OK;
err_free:
nftnl_chain_free(c);
return MNL_CB_OK;
}
static struct nftnl_chain_list *mnl_chain_dump(struct mnl_socket *nf_sock,
int family)
{
char buf[MNL_SOCKET_BUFFER_SIZE];
struct nlmsghdr *nlh;
struct nftnl_chain_list *nlc_list;
int ret;
nlc_list = nftnl_chain_list_alloc();
if (nlc_list == NULL)
memory_allocation_error();
nlh = nftnl_chain_nlmsg_build_hdr(buf, NFT_MSG_GETCHAIN, family,
NLM_F_DUMP, seq);
ret = mnl_talk(nf_sock, nlh, nlh->nlmsg_len, chain_cb, nlc_list);
if (ret < 0)
goto err;
return nlc_list;
err:
nftnl_chain_list_free(nlc_list);
return NULL;
}
/*
* Table
*/
static int table_cb(const struct nlmsghdr *nlh, void *data)
{
struct nftnl_table_list *nlt_list = data;
struct nftnl_table *t;
t = nftnl_table_alloc();
if (t == NULL)
memory_allocation_error();
if (nftnl_table_nlmsg_parse(nlh, t) < 0)
goto err_free;
nftnl_table_list_add_tail(t, nlt_list);
return MNL_CB_OK;
err_free:
nftnl_table_free(t);
return MNL_CB_OK;
}
static struct nftnl_table_list *mnl_table_dump(struct mnl_socket *nf_sock,
int family)
{
char buf[MNL_SOCKET_BUFFER_SIZE];
struct nlmsghdr *nlh;
struct nftnl_table_list *nlt_list;
int ret;
nlt_list = nftnl_table_list_alloc();
if (nlt_list == NULL)
memory_allocation_error();
nlh = nftnl_table_nlmsg_build_hdr(buf, NFT_MSG_GETTABLE, family,
NLM_F_DUMP, seq);
ret = mnl_talk(nf_sock, nlh, nlh->nlmsg_len, table_cb, nlt_list);
if (ret < 0)
goto err;
return nlt_list;
err:
nftnl_table_list_free(nlt_list);
return NULL;
}
/*
* Set elements
*/
static int set_elem_cb(const struct nlmsghdr *nlh, void *data)
{
nftnl_set_elems_nlmsg_parse(nlh, data);
return MNL_CB_OK;
}
static int mnl_setelem_get(struct mnl_socket *nf_sock, struct nftnl_set *nls)
{
char buf[MNL_SOCKET_BUFFER_SIZE];
struct nlmsghdr *nlh;
uint32_t family = nftnl_set_get_u32(nls, NFTNL_SET_FAMILY);
nlh = nftnl_set_nlmsg_build_hdr(buf, NFT_MSG_GETSETELEM, family,
NLM_F_DUMP|NLM_F_ACK, seq);
nftnl_set_nlmsg_build_payload(nlh, nls);
return mnl_talk(nf_sock, nlh, nlh->nlmsg_len, set_elem_cb, nls);
}
/*
* Set
*/
static int set_cb(const struct nlmsghdr *nlh, void *data)
{
struct nftnl_set_list *nls_list = data;
struct nftnl_set *s;
s = nftnl_set_alloc();
if (s == NULL)
memory_allocation_error();
if (nftnl_set_nlmsg_parse(nlh, s) < 0)
goto err_free;
nftnl_set_list_add_tail(s, nls_list);
return MNL_CB_OK;
err_free:
nftnl_set_free(s);
return MNL_CB_OK;
}
static struct nftnl_set_list *
mnl_set_dump(struct mnl_socket *nf_sock, int family)
{
char buf[MNL_SOCKET_BUFFER_SIZE];
struct nlmsghdr *nlh;
struct nftnl_set *s;
struct nftnl_set_list *nls_list;
struct nftnl_set *si;
struct nftnl_set_list_iter *i;
int ret;
s = nftnl_set_alloc();
if (s == NULL)
memory_allocation_error();
nlh = nftnl_set_nlmsg_build_hdr(buf, NFT_MSG_GETSET, family,
NLM_F_DUMP|NLM_F_ACK, seq);
nftnl_set_nlmsg_build_payload(nlh, s);
nftnl_set_free(s);
nls_list = nftnl_set_list_alloc();
if (nls_list == NULL)
memory_allocation_error();
ret = mnl_talk(nf_sock, nlh, nlh->nlmsg_len, set_cb, nls_list);
if (ret < 0)
goto err;
i = nftnl_set_list_iter_create(nls_list);
if (i == NULL)
memory_allocation_error();
si = nftnl_set_list_iter_next(i);
while (si != NULL) {
if (mnl_setelem_get(nf_sock, si) != 0) {
perror("E: Unable to get set elements");
nftnl_set_list_iter_destroy(i);
goto err;
}
si = nftnl_set_list_iter_next(i);
}
nftnl_set_list_iter_destroy(i);
return nls_list;
err:
nftnl_set_list_free(nls_list);
return NULL;
}
/*
* ruleset
*/
static struct nftnl_ruleset *mnl_ruleset_dump(struct mnl_socket *nf_sock)
{
struct nftnl_ruleset *rs;
struct nftnl_table_list *t;
struct nftnl_chain_list *c;
struct nftnl_set_list *s;
struct nftnl_rule_list *r;
rs = nftnl_ruleset_alloc();
if (rs == NULL)
memory_allocation_error();
t = mnl_table_dump(nf_sock, NFPROTO_UNSPEC);
if (t != NULL)
nftnl_ruleset_set(rs, NFTNL_RULESET_TABLELIST, t);
c = mnl_chain_dump(nf_sock, NFPROTO_UNSPEC);
if (c != NULL)
nftnl_ruleset_set(rs, NFTNL_RULESET_CHAINLIST, c);
s = mnl_set_dump(nf_sock, NFPROTO_UNSPEC);
if (s != NULL)
nftnl_ruleset_set(rs, NFTNL_RULESET_SETLIST, s);
r = mnl_rule_dump(nf_sock, NFPROTO_UNSPEC);
if (r != NULL)
nftnl_ruleset_set(rs, NFTNL_RULESET_RULELIST, r);
return rs;
}
int main(int argc, char *argv[])
{
struct mnl_socket *nl;
uint32_t type = NFTNL_OUTPUT_DEFAULT;
struct nftnl_ruleset *rs;
int ret;
if (argc > 2) {
fprintf(stderr, "%s\n", argv[0]);
exit(EXIT_FAILURE);
}
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);
}
seq = time(NULL);
rs = mnl_ruleset_dump(nl);
if (rs == NULL) {
perror("ruleset_dump");
exit(EXIT_FAILURE);
}
ret = nftnl_ruleset_fprintf(stdout, rs, type, 0);
fprintf(stdout, "\n");
if (ret == -1)
perror("E: Error during fprintf operations");
return 0;
}
nftnl_chain_list
Definition: chain.c:1016
nftnl_chain
Definition: chain.c:32
nftnl_rule_list
Definition: rule.c:746
nftnl_ruleset
Definition: ruleset.c:26
nftnl_set_list_iter
Definition: set.c:990
nftnl_set_list
Definition: set.c:899
nftnl_table_list
Definition: table.c:403
nftnl_table
Definition: table.c:28