libnftnl  1.2.8
expr/counter.c
1 /*
2  * (C) 2012 by Pablo Neira Ayuso <pablo@netfilter.org>
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published
6  * by the Free Software Foundation; either version 2 of the License, or
7  * (at your option) any later version.
8  *
9  * This code has been sponsored by Sophos Astaro <http://www.sophos.com>
10  */
11 
12 #include <stdio.h>
13 #include <stdint.h>
14 #include <arpa/inet.h>
15 #include <errno.h>
16 #include <inttypes.h>
17 
18 #include <linux/netfilter/nf_tables.h>
19 
20 #include "internal.h"
21 #include <libmnl/libmnl.h>
22 #include <libnftnl/expr.h>
23 #include <libnftnl/rule.h>
24 
26  uint64_t pkts;
27  uint64_t bytes;
28 };
29 
30 static int
31 nftnl_expr_counter_set(struct nftnl_expr *e, uint16_t type,
32  const void *data, uint32_t data_len)
33 {
34  struct nftnl_expr_counter *ctr = nftnl_expr_data(e);
35 
36  switch(type) {
37  case NFTNL_EXPR_CTR_BYTES:
38  memcpy(&ctr->bytes, data, data_len);
39  break;
40  case NFTNL_EXPR_CTR_PACKETS:
41  memcpy(&ctr->pkts, data, data_len);
42  break;
43  }
44  return 0;
45 }
46 
47 static const void *
48 nftnl_expr_counter_get(const struct nftnl_expr *e, uint16_t type,
49  uint32_t *data_len)
50 {
51  struct nftnl_expr_counter *ctr = nftnl_expr_data(e);
52 
53  switch(type) {
54  case NFTNL_EXPR_CTR_BYTES:
55  *data_len = sizeof(ctr->bytes);
56  return &ctr->bytes;
57  case NFTNL_EXPR_CTR_PACKETS:
58  *data_len = sizeof(ctr->pkts);
59  return &ctr->pkts;
60  }
61  return NULL;
62 }
63 
64 static int nftnl_expr_counter_cb(const struct nlattr *attr, void *data)
65 {
66  const struct nlattr **tb = data;
67  int type = mnl_attr_get_type(attr);
68 
69  if (mnl_attr_type_valid(attr, NFTA_COUNTER_MAX) < 0)
70  return MNL_CB_OK;
71 
72  switch(type) {
73  case NFTA_COUNTER_BYTES:
74  case NFTA_COUNTER_PACKETS:
75  if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
76  abi_breakage();
77  break;
78  }
79 
80  tb[type] = attr;
81  return MNL_CB_OK;
82 }
83 
84 static void
85 nftnl_expr_counter_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
86 {
87  struct nftnl_expr_counter *ctr = nftnl_expr_data(e);
88 
89  if (e->flags & (1 << NFTNL_EXPR_CTR_BYTES))
90  mnl_attr_put_u64(nlh, NFTA_COUNTER_BYTES, htobe64(ctr->bytes));
91  if (e->flags & (1 << NFTNL_EXPR_CTR_PACKETS))
92  mnl_attr_put_u64(nlh, NFTA_COUNTER_PACKETS, htobe64(ctr->pkts));
93 }
94 
95 static int
96 nftnl_expr_counter_parse(struct nftnl_expr *e, struct nlattr *attr)
97 {
98  struct nftnl_expr_counter *ctr = nftnl_expr_data(e);
99  struct nlattr *tb[NFTA_COUNTER_MAX+1] = {};
100 
101  if (mnl_attr_parse_nested(attr, nftnl_expr_counter_cb, tb) < 0)
102  return -1;
103 
104  if (tb[NFTA_COUNTER_BYTES]) {
105  ctr->bytes = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_BYTES]));
106  e->flags |= (1 << NFTNL_EXPR_CTR_BYTES);
107  }
108  if (tb[NFTA_COUNTER_PACKETS]) {
109  ctr->pkts = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_PACKETS]));
110  e->flags |= (1 << NFTNL_EXPR_CTR_PACKETS);
111  }
112 
113  return 0;
114 }
115 
116 static int nftnl_expr_counter_snprintf(char *buf, size_t len,
117  uint32_t flags,
118  const struct nftnl_expr *e)
119 {
120  struct nftnl_expr_counter *ctr = nftnl_expr_data(e);
121 
122  return snprintf(buf, len, "pkts %"PRIu64" bytes %"PRIu64" ",
123  ctr->pkts, ctr->bytes);
124 }
125 
126 static struct attr_policy counter_attr_policy[__NFTNL_EXPR_CTR_MAX] = {
127  [NFTNL_EXPR_CTR_PACKETS] = { .maxlen = sizeof(uint64_t) },
128  [NFTNL_EXPR_CTR_BYTES] = { .maxlen = sizeof(uint64_t) },
129 };
130 
131 struct expr_ops expr_ops_counter = {
132  .name = "counter",
133  .alloc_len = sizeof(struct nftnl_expr_counter),
134  .nftnl_max_attr = __NFTNL_EXPR_CTR_MAX - 1,
135  .attr_policy = counter_attr_policy,
136  .set = nftnl_expr_counter_set,
137  .get = nftnl_expr_counter_get,
138  .parse = nftnl_expr_counter_parse,
139  .build = nftnl_expr_counter_build,
140  .output = nftnl_expr_counter_snprintf,
141 };