From ca27aed04308a6899eecc3de4455526fb285957d Mon Sep 17 00:00:00 2001 From: Eric Leblond Date: Sat, 6 Jul 2013 17:33:14 +0200 Subject: examples: add insert rule example This program can insert a rule after a rule given by its handle. Signed-off-by: Eric Leblond Signed-off-by: Pablo Neira Ayuso --- examples/Makefile.am | 4 + examples/nft-rule-insert.c | 204 +++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 208 insertions(+) create mode 100644 examples/nft-rule-insert.c (limited to 'examples') diff --git a/examples/Makefile.am b/examples/Makefile.am index 8985d74..bf28bae 100644 --- a/examples/Makefile.am +++ b/examples/Makefile.am @@ -10,6 +10,7 @@ check_PROGRAMS = nft-table-add \ nft-chain-del \ nft-chain-get \ nft-rule-add \ + nft-rule-insert \ nft-rule-xml-add \ nft-rule-del \ nft-rule-get \ @@ -52,6 +53,9 @@ nft_chain_get_LDADD = ../src/libnftables.la ${LIBMNL_LIBS} nft_rule_add_SOURCES = nft-rule-add.c nft_rule_add_LDADD = ../src/libnftables.la ${LIBMNL_LIBS} +nft_rule_insert_SOURCES = nft-rule-insert.c +nft_rule_insert_LDADD = ../src/libnftables.la ${LIBMNL_LIBS} ${LIBXML_LIBS} + nft_rule_xml_add_SOURCES = nft-rule-xml-add.c nft_rule_xml_add_LDADD = ../src/libnftables.la ${LIBMNL_LIBS} diff --git a/examples/nft-rule-insert.c b/examples/nft-rule-insert.c new file mode 100644 index 0000000..1418127 --- /dev/null +++ b/examples/nft-rule-insert.c @@ -0,0 +1,204 @@ +/* + * (C) 2012 by Pablo Neira Ayuso + * (C) 2013 by Eric Leblond + * + * 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 /* for offsetof */ +#include +#include + +#include + +#include +#include +#include + +#include +#include + +#include + +static void add_target_log(struct nft_rule_expr *e) +{ + struct ipt_log_info *info; + + nft_rule_expr_set(e, NFT_EXPR_TG_NAME, "LOG", strlen("LOG")); + nft_rule_expr_set_u32(e, NFT_EXPR_TG_REV, 0); + + info = calloc(1, sizeof(struct ipt_log_info)); + if (info == NULL) + return; + + sprintf(info->prefix, "test: "); + info->prefix[sizeof(info->prefix)-1] = '\0'; + info->logflags = 0x0f; + info->level = 5; + + nft_rule_expr_set(e, NFT_EXPR_TG_INFO, info, sizeof(*info)); +} + +static void add_expr_target(struct nft_rule *r) +{ + struct nft_rule_expr *expr; + + expr = nft_rule_expr_alloc("target"); + if (expr == NULL) + return; + + add_target_log(expr); + + nft_rule_add_expr(r, expr); +} + +static void add_match_iprange(struct nft_rule_expr *e) +{ + struct xt_iprange_mtinfo *info; + + nft_rule_expr_set(e, NFT_EXPR_MT_NAME, "iprange", strlen("iprange")); + nft_rule_expr_set_u32(e, NFT_EXPR_MT_REV, 1); + + info = calloc(1, sizeof(struct xt_iprange_mtinfo)); + if (info == NULL) + return; + + info->src_min.ip = info->dst_min.ip = inet_addr("127.0.0.1"); + info->src_max.ip = info->dst_max.ip = inet_addr("127.0.0.1"); + info->flags = IPRANGE_SRC; + + nft_rule_expr_set(e, NFT_EXPR_MT_INFO, info, sizeof(*info)); +} + +static void add_expr_match(struct nft_rule *r) +{ + struct nft_rule_expr *expr; + + expr = nft_rule_expr_alloc("match"); + if (expr == NULL) + return; + + add_match_iprange(expr); + + nft_rule_add_expr(r, expr); +} + +#define field_sizeof(t, f) (sizeof(((t *)NULL)->f)) + +static void add_payload2(struct nft_rule_expr *e) +{ + nft_rule_expr_set_u32(e, NFT_EXPR_PAYLOAD_BASE, + NFT_PAYLOAD_NETWORK_HEADER); + nft_rule_expr_set_u32(e, NFT_EXPR_PAYLOAD_DREG, NFT_REG_1); + nft_rule_expr_set_u32(e, NFT_EXPR_PAYLOAD_OFFSET, + offsetof(struct iphdr, protocol)); + nft_rule_expr_set_u32(e, NFT_EXPR_PAYLOAD_LEN, 1); +} + +static void add_payload(struct nft_rule *r) +{ + struct nft_rule_expr *expr; + + expr = nft_rule_expr_alloc("payload"); + if (expr == NULL) + return; + + add_payload2(expr); + + nft_rule_add_expr(r, expr); +} + +int main(int argc, char *argv[]) +{ + struct mnl_socket *nl; + char buf[MNL_SOCKET_BUFFER_SIZE]; + struct nlmsghdr *nlh; + uint32_t portid, seq; + struct nft_rule *r = NULL; + int ret, family; + uint64_t handle; + + if (argc != 5) { + fprintf(stderr, "Usage: %s \n", + argv[0]); + exit(EXIT_FAILURE); + } + + r = nft_rule_alloc(); + if (r == NULL) { + perror("OOM"); + exit(EXIT_FAILURE); + } + + if (strcmp(argv[1], "ip") == 0) + family = AF_INET; + else if (strcmp(argv[1], "ip6") == 0) + family = AF_INET6; + else if (strcmp(argv[1], "bridge") == 0) + family = AF_BRIDGE; + else { + fprintf(stderr, "Unknown family: ip, ip6, bridge\n"); + exit(EXIT_FAILURE); + } + + nft_rule_attr_set(r, NFT_RULE_ATTR_TABLE, argv[2]); + nft_rule_attr_set(r, NFT_RULE_ATTR_CHAIN, argv[3]); + + handle = atoi(argv[4]); + nft_rule_attr_set(r, NFT_RULE_ATTR_POSITION, &handle); + + add_expr_match(r); + add_payload(r); + add_expr_target(r); + + char tmp[1024]; + nft_rule_snprintf(tmp, sizeof(tmp), r, 0, 0); + printf("%s\n", tmp); + + seq = time(NULL); + nlh = nft_rule_nlmsg_build_hdr(buf, NFT_MSG_NEWRULE, family, + NLM_F_ACK|NLM_F_CREATE, + seq); + nft_rule_nlmsg_build_payload(nlh, r); + nft_rule_free(r); + + 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, 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; +} -- cgit v1.2.3