1 files changed, 142 insertions, 0 deletions
diff --git a/examples/nft-ct-expectation-get.c b/examples/nft-ct-expectation-get.c
new file mode 100644
index 0000000..12c1350
--- /dev/null
+++ b/examples/nft-ct-expectation-get.c
@@ -0,0 +1,142 @@
+/*
+ * (C) 2019 by Stéphane Veyret <sveyret@gmail.com>
+ *
+ * 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.
+ */
+
+#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/object.h>
+
+static uint16_t parse_family(char *str, const char *option)
+{
+	if (strcmp(str, "ip") == 0)
+		return NFPROTO_IPV4;
+	else if (strcmp(str, "ip6") == 0)
+		return NFPROTO_IPV6;
+	else if (strcmp(str, "inet") == 0)
+		return NFPROTO_INET;
+	else if (strcmp(str, "arp") == 0)
+		return NFPROTO_INET;
+	fprintf(stderr, "Unknown %s: ip, ip6, inet, arp\n", option);
+	exit(EXIT_FAILURE);
+}
+
+static struct nftnl_obj *obj_parse(int argc, char *argv[])
+{
+	struct nftnl_obj *t;
+	uint16_t family;
+
+	t = nftnl_obj_alloc();
+	if (t == NULL) {
+		perror("OOM");
+		return NULL;
+	}
+
+	family = parse_family(argv[1], "family");
+	nftnl_obj_set_u32(t, NFTNL_OBJ_FAMILY, family);
+	nftnl_obj_set_u32(t, NFTNL_OBJ_TYPE, NFT_OBJECT_CT_EXPECT);
+	nftnl_obj_set_str(t, NFTNL_OBJ_TABLE, argv[2]);
+
+	if (argc > 3)
+		nftnl_obj_set_str(t, NFTNL_OBJ_NAME, argv[3]);
+
+	return t;
+}
+
+static int obj_cb(const struct nlmsghdr *nlh, void *data)
+{
+	uint32_t *type = data;
+	struct nftnl_obj *t;
+	char buf[4096];
+
+	t = nftnl_obj_alloc();
+	if (t == NULL) {
+		perror("OOM");
+		goto err;
+	}
+
+	if (nftnl_obj_nlmsg_parse(nlh, t) < 0) {
+		perror("nftnl_obj_nlmsg_parse");
+		goto err_free;
+	}
+
+	nftnl_obj_snprintf(buf, sizeof(buf), t, *type, 0);
+	printf("%s\n", buf);
+
+err_free:
+	nftnl_obj_free(t);
+err:
+	return MNL_CB_OK;
+}
+
+int main(int argc, char *argv[])
+{
+	struct mnl_socket *nl;
+	char buf[MNL_SOCKET_BUFFER_SIZE];
+	struct nlmsghdr *nlh;
+	uint32_t portid, seq, family;
+	struct nftnl_obj *t;
+	int ret;
+	uint32_t type = NFTNL_OUTPUT_DEFAULT;
+	uint16_t flags = NLM_F_ACK;
+
+	if (argc < 3 || argc > 4) {
+		fprintf(stderr, "%s <family> <table> [<name>]\n", argv[0]);
+		return EXIT_FAILURE;
+	}
+
+	t = obj_parse(argc, argv);
+	if (t == NULL)
+		exit(EXIT_FAILURE);
+	family = nftnl_obj_get_u32(t, NFTNL_OBJ_FAMILY);
+
+	seq = time(NULL);
+	if (argc < 4)
+		flags = NLM_F_DUMP;
+	nlh = nftnl_nlmsg_build_hdr(buf, NFT_MSG_GETOBJ, family, flags, seq);
+	nftnl_obj_nlmsg_build_payload(nlh, t);
+	nftnl_obj_free(t);
+
+	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, obj_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;
+}