1 files changed, 377 insertions, 0 deletions
diff --git a/examples/nft-ruleset-get.c b/examples/nft-ruleset-get.c
new file mode 100644
index 0000000..34ebe1f
--- /dev/null
+++ b/examples/nft-ruleset-get.c
@@ -0,0 +1,377 @@
+/*
+ * Copyright (c) 2013 Arturo Borrero Gonzalez <arturo@debian.org>
+ *
+ * based on previous code from:
+ *
+ * Copyright (c) 2013 Pablo Neira Ayuso <pablo@netfilter.org>
+ *
+ * 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.
+ *
+ */
+
+#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_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_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_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_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_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;
+}