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Diffstat (limited to 'examples/nft-ct-expectation-add.c')
| -rw-r--r-- | examples/nft-ct-expectation-add.c | 153 |
1 files changed, 153 insertions, 0 deletions
diff --git a/examples/nft-ct-expectation-add.c b/examples/nft-ct-expectation-add.c new file mode 100644 index 0000000..d9b9cdb --- /dev/null +++ b/examples/nft-ct-expectation-add.c @@ -0,0 +1,153 @@ +/* + * (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 <time.h> +#include <string.h> +#include <netinet/in.h> + +#include <linux/netfilter.h> + +#include <obj.h> +#include <libmnl/libmnl.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 uint8_t parse_l4proto(char *str) +{ + if (strcmp(str, "udp") == 0) + return IPPROTO_UDP; + else if (strcmp(str, "tcp") == 0) + return IPPROTO_TCP; + else { + fprintf(stderr, "Unknown l4proto: tcp, udp\n"); + exit(EXIT_FAILURE); + } + return IPPROTO_TCP; +} + +static struct nftnl_obj *obj_parse(int argc, char *argv[]) +{ + uint16_t family, l3proto, dport; + uint8_t l4proto, size; + struct nftnl_obj *t; + uint32_t timeout; + + 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]); + nftnl_obj_set_str(t, NFTNL_OBJ_NAME, argv[3]); + + if (argc > 8) { + l3proto = parse_family(argv[8], "l3proto"); + nftnl_obj_set_u16(t, NFTNL_OBJ_CT_EXPECT_L3PROTO, l3proto); + } + l4proto = parse_l4proto(argv[4]); + nftnl_obj_set_u8(t, NFTNL_OBJ_CT_EXPECT_L4PROTO, l4proto); + dport = atoi(argv[5]); + nftnl_obj_set_u16(t, NFTNL_OBJ_CT_EXPECT_DPORT, dport); + timeout = atol(argv[6]); + nftnl_obj_set_u32(t, NFTNL_OBJ_CT_EXPECT_TIMEOUT, timeout); + size = atoi(argv[7]); + nftnl_obj_set_u8(t, NFTNL_OBJ_CT_EXPECT_SIZE, size); + + return t; +} + +int main(int argc, char *argv[]) +{ + uint32_t portid, seq, obj_seq, family; + char buf[MNL_SOCKET_BUFFER_SIZE]; + struct mnl_nlmsg_batch *batch; + struct mnl_socket *nl; + struct nlmsghdr *nlh; + struct nftnl_obj *t; + int ret; + + if (argc < 8 || argc > 9) { + fprintf(stderr, "%s <family> <table> <name> <l4proto> <dport> <timeout> <size> [l3proto]\n", argv[0]); + exit(EXIT_FAILURE); + } + + t = obj_parse(argc, argv); + if (t == NULL) { + exit(EXIT_FAILURE); + } + + seq = time(NULL); + batch = mnl_nlmsg_batch_start(buf, sizeof(buf)); + + nftnl_batch_begin(mnl_nlmsg_batch_current(batch), seq++); + mnl_nlmsg_batch_next(batch); + + obj_seq = seq; + family = nftnl_obj_get_u32(t, NFTNL_OBJ_FAMILY); + nlh = nftnl_nlmsg_build_hdr(mnl_nlmsg_batch_current(batch), + NFT_MSG_NEWOBJ, family, + NLM_F_ACK | NLM_F_CREATE, seq++); + nftnl_obj_nlmsg_build_payload(nlh, t); + nftnl_obj_free(t); + mnl_nlmsg_batch_next(batch); + + nftnl_batch_end(mnl_nlmsg_batch_current(batch), seq++); + mnl_nlmsg_batch_next(batch); + + 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, mnl_nlmsg_batch_head(batch), + mnl_nlmsg_batch_size(batch)) < 0) { + perror("mnl_socket_send"); + exit(EXIT_FAILURE); + } + + mnl_nlmsg_batch_stop(batch); + + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); + while (ret > 0) { + ret = mnl_cb_run(buf, ret, obj_seq, portid, NULL, NULL); + 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; +} |