From 1ff21a68502d67e056100da7e0da074467bc08ed Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Sat, 9 Feb 2013 18:22:13 +0100 Subject: add xtables-events Add new program to listen to rule updates: shell$ xtables-events -A INPUT -m state --state ESTABLISHED -j ACCEPT -A INPUT -p tcp -m tcp --dport 22 -j ACCEPT -D INPUT -p tcp -m tcp --dport 22 -j ACCEPT -D INPUT -m state --state ESTABLISHED -j ACCEPT You can use `-c' option to display counters. Signed-off-by: Pablo Neira Ayuso --- iptables/Makefile.am | 5 +- iptables/nft.c | 19 +++-- iptables/nft.h | 7 ++ iptables/xtables-events.c | 208 ++++++++++++++++++++++++++++++++++++++++++++++ iptables/xtables-multi.c | 1 + iptables/xtables-multi.h | 1 + 6 files changed, 234 insertions(+), 7 deletions(-) create mode 100644 iptables/xtables-events.c (limited to 'iptables') diff --git a/iptables/Makefile.am b/iptables/Makefile.am index 2b1f3fa4..2ed16960 100644 --- a/iptables/Makefile.am +++ b/iptables/Makefile.am @@ -31,7 +31,7 @@ if HAVE_LIBNFTABLES xtables_multi_SOURCES += xtables-save.c xtables-restore.c \ xtables-standalone.c xtables.c nft.c \ xtables-config-parser.y xtables-config-syntax.l \ - xtables-config.c + xtables-config.c xtables-events.c xtables_multi_LDADD += -lmnl -lnftables xtables_multi_CFLAGS += -DENABLE_NFTABLES # yacc and lex generate dirty code @@ -55,7 +55,8 @@ if ENABLE_IPV6 v6_sbin_links = ip6tables ip6tables-restore ip6tables-save endif if ENABLE_NFTABLES -x_sbin_links = xtables xtables-restore xtables-save xtables-config +x_sbin_links = xtables xtables-restore xtables-save xtables-config \ + xtables-events endif iptables-extensions.8: iptables-extensions.8.tmpl ../extensions/matches.man ../extensions/targets.man diff --git a/iptables/nft.c b/iptables/nft.c index cef1f32e..097c28b9 100644 --- a/iptables/nft.c +++ b/iptables/nft.c @@ -1385,13 +1385,22 @@ nft_print_counters(struct nft_rule_expr *e, struct nft_rule_expr_iter *iter, } } -static void nft_rule_print_save(struct nft_rule *r, bool counters) +void +nft_rule_print_save(struct nft_rule *r, enum nft_rule_print type, bool counters) { struct nft_rule_expr_iter *iter; struct nft_rule_expr *expr; + const char *chain = nft_rule_attr_get_str(r, NFT_RULE_ATTR_CHAIN); /* print chain name */ - printf("-A %s ", nft_rule_attr_get_str(r, NFT_RULE_ATTR_CHAIN)); + switch(type) { + case NFT_RULE_APPEND: + printf("-A %s ", chain); + break; + case NFT_RULE_DEL: + printf("-D %s ", chain); + break; + } iter = nft_rule_expr_iter_create(r); if (iter == NULL) @@ -1614,7 +1623,7 @@ int nft_rule_save(struct nft_handle *h, const char *table, bool counters) if (strcmp(table, rule_table) != 0) goto next; - nft_rule_print_save(r, counters); + nft_rule_print_save(r, NFT_RULE_APPEND, counters); next: r = nft_rule_list_iter_next(iter); @@ -2714,7 +2723,7 @@ nft_rule_find(struct nft_rule_list *list, const char *chain, const char *table, /* Delete by matching rule case */ DEBUGP("comparing with... "); #ifdef DEBUG_DEL - nft_rule_print_save(r, 0); + nft_rule_print_save(r, NFT_RULE_APPEND, 0); #endif nft_rule_to_iptables_command_state(r, &this); @@ -3378,7 +3387,7 @@ static void list_save(const struct iptables_command_state *cs, struct nft_rule *r, unsigned int num, unsigned int format) { - nft_rule_print_save(r, !(format & FMT_NOCOUNTS)); + nft_rule_print_save(r, NFT_RULE_APPEND, !(format & FMT_NOCOUNTS)); } static int diff --git a/iptables/nft.h b/iptables/nft.h index 834fff0d..3cffb777 100644 --- a/iptables/nft.h +++ b/iptables/nft.h @@ -56,6 +56,13 @@ int nft_rule_list_save(struct nft_handle *h, const char *chain, const char *tabl int nft_rule_save(struct nft_handle *h, const char *table, bool counters); int nft_rule_flush(struct nft_handle *h, const char *chain, const char *table); +enum nft_rule_print { + NFT_RULE_APPEND, + NFT_RULE_DEL, +}; + +void nft_rule_print_save(struct nft_rule *r, enum nft_rule_print type, bool counters); + /* * global commit and abort */ diff --git a/iptables/xtables-events.c b/iptables/xtables-events.c new file mode 100644 index 00000000..2600a250 --- /dev/null +++ b/iptables/xtables-events.c @@ -0,0 +1,208 @@ +/* + * (C) 2012-2013 by Pablo Neira Ayuso + * + * 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 + */ + +#include +#include +#include +#include +#include + +#include +#include + +#include +#include +#include +#include + +#include +#include "iptables.h" /* for xtables_globals */ +#include "xtables-multi.h" +#include "nft.h" + +static int table_cb(const struct nlmsghdr *nlh, int type) +{ + struct nft_table *t; + char buf[4096]; + + t = nft_table_alloc(); + if (t == NULL) { + perror("OOM"); + goto err; + } + + if (nft_table_nlmsg_parse(nlh, t) < 0) { + perror("nft_table_nlmsg_parse"); + goto err_free; + } + + nft_table_snprintf(buf, sizeof(buf), t, NFT_TABLE_O_DEFAULT, 0); + /* FIXME: define syntax to represent table events */ + printf("# [table: %s]\t%s", type == NFT_MSG_NEWTABLE ? "NEW" : "DEL", buf); + +err_free: + nft_table_free(t); +err: + return MNL_CB_OK; +} + +static bool counters; + +static int rule_cb(const struct nlmsghdr *nlh, int type) +{ + struct nft_rule *r; + + r = nft_rule_alloc(); + if (r == NULL) { + perror("OOM"); + goto err; + } + + if (nft_rule_nlmsg_parse(nlh, r) < 0) { + perror("nft_rule_nlmsg_parse"); + goto err_free; + } + + switch(nft_rule_attr_get_u8(r, NFT_RULE_ATTR_FAMILY)) { + case AF_INET: + printf("-4 "); + break; + case AF_INET6: + printf("-6 "); + break; + default: + break; + } + + nft_rule_print_save(r, type == NFT_MSG_NEWRULE ? NFT_RULE_APPEND : + NFT_RULE_DEL, + counters); +err_free: + nft_rule_free(r); +err: + return MNL_CB_OK; +} + +static int chain_cb(const struct nlmsghdr *nlh, int type) +{ + struct nft_chain *t; + char buf[4096]; + + t = nft_chain_alloc(); + if (t == NULL) { + perror("OOM"); + goto err; + } + + if (nft_chain_nlmsg_parse(nlh, t) < 0) { + perror("nft_chain_nlmsg_parse"); + goto err_free; + } + + nft_chain_snprintf(buf, sizeof(buf), t, NFT_CHAIN_O_DEFAULT, 0); + /* FIXME: define syntax to represent chain events */ + printf("# [chain: %s]\t%s", type == NFT_MSG_NEWCHAIN ? "NEW" : "DEL", buf); + +err_free: + nft_chain_free(t); +err: + return MNL_CB_OK; +} + +static int events_cb(const struct nlmsghdr *nlh, void *data) +{ + int ret = MNL_CB_OK; + int type = nlh->nlmsg_type & 0xFF; + + switch(type) { + case NFT_MSG_NEWTABLE: + case NFT_MSG_DELTABLE: + ret = table_cb(nlh, type); + break; + case NFT_MSG_NEWCHAIN: + case NFT_MSG_DELCHAIN: + ret = chain_cb(nlh, type); + break; + case NFT_MSG_NEWRULE: + case NFT_MSG_DELRULE: + ret = rule_cb(nlh, type); + break; + } + + return ret; +} + +static const struct option options[] = { + {.name = "counters", .has_arg = false, .val = 'c'}, + {NULL}, +}; + +static void print_usage(const char *name, const char *version) +{ + fprintf(stderr, "Usage: %s [-c]\n" + " [ --counters ]\n", name); + exit(EXIT_FAILURE); +} + +int xtables_events_main(int argc, char *argv[]) +{ + struct mnl_socket *nl; + char buf[MNL_SOCKET_BUFFER_SIZE]; + int ret, c; + + xtables_globals.program_name = "xtables-events"; + /* XXX xtables_init_all does several things we don't want */ + c = xtables_init_all(&xtables_globals, NFPROTO_IPV4); + if (c < 0) { + fprintf(stderr, "%s/%s Failed to initialize xtables\n", + xtables_globals.program_name, + xtables_globals.program_version); + exit(1); + } +#if defined(ALL_INCLUSIVE) || defined(NO_SHARED_LIBS) + init_extensions(); + init_extensions4(); +#endif + + while ((c = getopt_long(argc, argv, "c", options, NULL)) != -1) { + switch (c) { + case 'c': + counters = true; + break; + } + } + + 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, 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; +} diff --git a/iptables/xtables-multi.c b/iptables/xtables-multi.c index c1746434..5732ba38 100644 --- a/iptables/xtables-multi.c +++ b/iptables/xtables-multi.c @@ -41,6 +41,7 @@ static const struct subcommand multi_subcommands[] = { {"xtables-save", xtables_save_main}, {"xtables-restore", xtables_restore_main}, {"xtables-config", xtables_config_main}, + {"xtables-events", xtables_events_main}, #endif {NULL}, }; diff --git a/iptables/xtables-multi.h b/iptables/xtables-multi.h index be2b3ad8..c609ea5b 100644 --- a/iptables/xtables-multi.h +++ b/iptables/xtables-multi.h @@ -6,5 +6,6 @@ extern int xtables_main(int, char **); extern int xtables_save_main(int, char **); extern int xtables_restore_main(int, char **); extern int xtables_config_main(int, char **); +extern int xtables_events_main(int, char **); #endif /* _XTABLES_MULTI_H */ -- cgit v1.2.3