diff options
Diffstat (limited to 'examples/nft-events.c')
| -rw-r--r-- | examples/nft-events.c | 268 |
1 files changed, 268 insertions, 0 deletions
diff --git a/examples/nft-events.c b/examples/nft-events.c new file mode 100644 index 0000000..8aab90a --- /dev/null +++ b/examples/nft-events.c @@ -0,0 +1,268 @@ +/* + * (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/nfnetlink.h> +#include <linux/netfilter/nf_tables.h> + +#include <libmnl/libmnl.h> +#include <libnftnl/table.h> +#include <libnftnl/chain.h> +#include <libnftnl/rule.h> +#include <libnftnl/set.h> +#include <libnftnl/gen.h> +#include <libnftnl/common.h> + +static uint32_t event2flag(uint32_t event) +{ + switch (event) { + case NFT_MSG_NEWTABLE: + case NFT_MSG_NEWCHAIN: + case NFT_MSG_NEWRULE: + case NFT_MSG_NEWSET: + case NFT_MSG_NEWSETELEM: + case NFT_MSG_NEWGEN: + return NFTNL_OF_EVENT_NEW; + case NFT_MSG_DELTABLE: + case NFT_MSG_DELCHAIN: + case NFT_MSG_DELRULE: + case NFT_MSG_DELSET: + case NFT_MSG_DELSETELEM: + return NFTNL_OF_EVENT_DEL; + } + + return 0; +} + +static int table_cb(const struct nlmsghdr *nlh, int event, int type) +{ + struct nftnl_table *t; + + t = nftnl_table_alloc(); + if (t == NULL) { + perror("OOM"); + goto err; + } + + if (nftnl_table_nlmsg_parse(nlh, t) < 0) { + perror("nftnl_table_nlmsg_parse"); + goto err_free; + } + + nftnl_table_fprintf(stdout, t, type, event2flag(event)); + fprintf(stdout, "\n"); + +err_free: + nftnl_table_free(t); +err: + return MNL_CB_OK; +} + +static int rule_cb(const struct nlmsghdr *nlh, int event, int type) +{ + struct nftnl_rule *t; + + 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_fprintf(stdout, t, type, event2flag(event)); + fprintf(stdout, "\n"); + +err_free: + nftnl_rule_free(t); +err: + return MNL_CB_OK; +} + +static int chain_cb(const struct nlmsghdr *nlh, int event, int type) +{ + struct nftnl_chain *t; + + t = nftnl_chain_alloc(); + if (t == NULL) { + perror("OOM"); + goto err; + } + + if (nftnl_chain_nlmsg_parse(nlh, t) < 0) { + perror("nftnl_chain_nlmsg_parse"); + goto err_free; + } + + nftnl_chain_fprintf(stdout, t, type, event2flag(event)); + fprintf(stdout, "\n"); + +err_free: + nftnl_chain_free(t); +err: + return MNL_CB_OK; +} + +static int set_cb(const struct nlmsghdr *nlh, int event, int type) +{ + struct nftnl_set *t; + + t = nftnl_set_alloc(); + if (t == NULL) { + perror("OOM"); + goto err; + } + + if (nftnl_set_nlmsg_parse(nlh, t) < 0) { + perror("nftnl_set_nlmsg_parse"); + goto err_free; + } + + nftnl_set_fprintf(stdout, t, type, event2flag(event)); + fprintf(stdout, "\n"); + +err_free: + nftnl_set_free(t); +err: + return MNL_CB_OK; +} + +static int setelem_cb(const struct nlmsghdr *nlh, int event, int type) +{ + + struct nftnl_set *s; + + s = nftnl_set_alloc(); + if (s == NULL) { + perror("OOM"); + goto err; + } + + if (nftnl_set_elems_nlmsg_parse(nlh, s) < 0) { + perror("nftnl_set_nlmsg_parse"); + goto err_free; + } + + nftnl_set_fprintf(stdout, s, type, event2flag(event)); + fprintf(stdout, "\n"); + +err_free: + nftnl_set_free(s); +err: + return MNL_CB_OK; +} + +static int gen_cb(const struct nlmsghdr *nlh, int event, int type) +{ + struct nftnl_gen *gen; + + gen = nftnl_gen_alloc(); + if (gen == NULL) { + perror("OOM"); + goto err; + } + + if (nftnl_gen_nlmsg_parse(nlh, gen) < 0) { + perror("nftnl_gen_parse"); + goto err_free; + } + + nftnl_gen_fprintf(stdout, gen, type, event2flag(event)); + fprintf(stdout, "\n"); +err_free: + nftnl_gen_free(gen); +err: + return MNL_CB_OK; +} + +static int events_cb(const struct nlmsghdr *nlh, void *data) +{ + int ret = MNL_CB_OK; + int event = NFNL_MSG_TYPE(nlh->nlmsg_type); + int type = *((int *)data); + + switch(event) { + case NFT_MSG_NEWTABLE: + case NFT_MSG_DELTABLE: + ret = table_cb(nlh, event, type); + break; + case NFT_MSG_NEWCHAIN: + case NFT_MSG_DELCHAIN: + ret = chain_cb(nlh, event, type); + break; + case NFT_MSG_NEWRULE: + case NFT_MSG_DELRULE: + ret = rule_cb(nlh, event, type); + break; + case NFT_MSG_NEWSET: + case NFT_MSG_DELSET: + ret = set_cb(nlh, event, type); + break; + case NFT_MSG_NEWSETELEM: + case NFT_MSG_DELSETELEM: + ret = setelem_cb(nlh, event, type); + break; + case NFT_MSG_NEWGEN: + ret = gen_cb(nlh, event, type); + break; + } + + return ret; +} + +int main(int argc, char *argv[]) +{ + struct mnl_socket *nl; + char buf[MNL_SOCKET_BUFFER_SIZE]; + int ret, type; + + switch (argc) { + case 1: + type = NFTNL_OUTPUT_DEFAULT; + break; + default: + fprintf(stderr, "%s\n", argv[0]); + return EXIT_FAILURE; + } + + nl = mnl_socket_open(NETLINK_NETFILTER); + if (nl == NULL) { + perror("mnl_socket_open"); + exit(EXIT_FAILURE); + } + + if (mnl_socket_bind(nl, (1 << (NFNLGRP_NFTABLES-1)), MNL_SOCKET_AUTOPID) < 0) { + perror("mnl_socket_bind"); + exit(EXIT_FAILURE); + } + + ret = mnl_socket_recvfrom(nl, buf, sizeof(buf)); + while (ret > 0) { + ret = mnl_cb_run(buf, ret, 0, 0, events_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; +} |