From 00c179b4c9f9f9394cc6f79e5f2a68410631fd72 Mon Sep 17 00:00:00 2001 From: Pablo Neira Ayuso Date: Fri, 3 Aug 2012 17:31:48 +0200 Subject: initial version of libnftables It adds support for table, chain and rule handling. This also includes expression handling for each rule. Signed-off-by: Pablo Neira Ayuso --- src/expr/counter.c | 145 +++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 145 insertions(+) create mode 100644 src/expr/counter.c (limited to 'src/expr/counter.c') diff --git a/src/expr/counter.c b/src/expr/counter.c new file mode 100644 index 0000000..26b7d6f --- /dev/null +++ b/src/expr/counter.c @@ -0,0 +1,145 @@ +/* + * (C) 2012 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 code has been sponsored by Sophos Astaro + */ + +#include +#include +#include + +#include + +#include "internal.h" +#include +#include +#include "expr_ops.h" + +struct nft_expr_counter { + uint64_t pkts; + uint64_t bytes; +}; + +static int +nft_rule_expr_counter_set(struct nft_rule_expr *e, uint16_t type, + const void *data, size_t data_len) +{ + struct nft_expr_counter *ctr = (struct nft_expr_counter *)e->data; + + switch(type) { + case NFT_EXPR_CTR_BYTES: + ctr->bytes = *((uint64_t *)data); + break; + case NFT_EXPR_CTR_PACKETS: + ctr->pkts = *((uint64_t *)data); + break; + default: + return -1; + } + return 0; +} + +static const void * +nft_rule_expr_counter_get(struct nft_rule_expr *e, uint16_t type, size_t *data_len) +{ + struct nft_expr_counter *ctr = (struct nft_expr_counter *)e->data; + + switch(type) { + case NFT_EXPR_CTR_BYTES: + if (e->flags & (1 << NFT_EXPR_CTR_BYTES)) { + *data_len = sizeof(ctr->bytes); + return &ctr->bytes; + } else + return NULL; + break; + case NFT_EXPR_CTR_PACKETS: + if (e->flags & (1 << NFT_EXPR_CTR_PACKETS)) { + *data_len = sizeof(ctr->pkts); + return &ctr->pkts; + } else + return NULL; + break; + default: + break; + } + return NULL; +} + +static int nft_rule_expr_counter_cb(const struct nlattr *attr, void *data) +{ + const struct nlattr **tb = data; + int type = mnl_attr_get_type(attr); + + if (mnl_attr_type_valid(attr, NFTA_COUNTER_MAX) < 0) + return MNL_CB_OK; + + switch(type) { + case NFTA_COUNTER_BYTES: + case NFTA_COUNTER_PACKETS: + if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0) { + perror("mnl_attr_validate"); + return MNL_CB_ERROR; + } + break; + } + + tb[type] = attr; + return MNL_CB_OK; +} + +static void +nft_rule_expr_counter_build(struct nlmsghdr *nlh, struct nft_rule_expr *e) +{ + struct nft_expr_counter *ctr = (struct nft_expr_counter *)e->data; + + if (e->flags & (1 << NFT_EXPR_CTR_BYTES)) + mnl_attr_put_u64(nlh, NFTA_COUNTER_BYTES, htobe64(ctr->bytes)); + if (e->flags & (1 << NFT_EXPR_CTR_PACKETS)) + mnl_attr_put_u64(nlh, NFTA_COUNTER_PACKETS, htobe64(ctr->pkts)); +} + +static int +nft_rule_expr_counter_parse(struct nft_rule_expr *e, struct nlattr *attr) +{ + struct nft_expr_counter *ctr = (struct nft_expr_counter *)e->data; + struct nlattr *tb[NFTA_COUNTER_MAX+1] = {}; + + if (mnl_attr_parse_nested(attr, nft_rule_expr_counter_cb, tb) < 0) + return -1; + + if (tb[NFTA_COUNTER_BYTES]) { + ctr->bytes = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_BYTES])); + e->flags |= (1 << NFT_EXPR_CTR_BYTES); + } + if (tb[NFTA_COUNTER_PACKETS]) { + ctr->pkts = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_PACKETS])); + e->flags |= (1 << NFT_EXPR_CTR_PACKETS); + } + + return 0; +} + +static int +nft_rule_expr_counter_snprintf(char *buf, size_t len, struct nft_rule_expr *e) +{ + struct nft_expr_counter *ctr = (struct nft_expr_counter *)e->data; + + return snprintf(buf, len, "pkts=%lu bytes=%lu ", + ctr->pkts, ctr->bytes); +} + +struct expr_ops expr_ops_counter = { + .name = "counter", + .alloc_len = sizeof(struct nft_expr_counter), + .max_attr = NFTA_COUNTER_MAX, + .set = nft_rule_expr_counter_set, + .get = nft_rule_expr_counter_get, + .parse = nft_rule_expr_counter_parse, + .build = nft_rule_expr_counter_build, + .snprintf = nft_rule_expr_counter_snprintf, +}; -- cgit v1.2.3