libnftnl  1.2.9
expr/counter.c
1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * (C) 2012 by Pablo Neira Ayuso <pablo@netfilter.org>
4  *
5  * This code has been sponsored by Sophos Astaro <http://www.sophos.com>
6  */
7 
8 #include <stdio.h>
9 #include <stdint.h>
10 #include <arpa/inet.h>
11 #include <errno.h>
12 #include <inttypes.h>
13 
14 #include <linux/netfilter/nf_tables.h>
15 
16 #include "internal.h"
17 #include <libmnl/libmnl.h>
18 #include <libnftnl/expr.h>
19 #include <libnftnl/rule.h>
20 
22  uint64_t pkts;
23  uint64_t bytes;
24 };
25 
26 static int
27 nftnl_expr_counter_set(struct nftnl_expr *e, uint16_t type,
28  const void *data, uint32_t data_len)
29 {
30  struct nftnl_expr_counter *ctr = nftnl_expr_data(e);
31 
32  switch(type) {
33  case NFTNL_EXPR_CTR_BYTES:
34  memcpy(&ctr->bytes, data, data_len);
35  break;
36  case NFTNL_EXPR_CTR_PACKETS:
37  memcpy(&ctr->pkts, data, data_len);
38  break;
39  }
40  return 0;
41 }
42 
43 static const void *
44 nftnl_expr_counter_get(const struct nftnl_expr *e, uint16_t type,
45  uint32_t *data_len)
46 {
47  struct nftnl_expr_counter *ctr = nftnl_expr_data(e);
48 
49  switch(type) {
50  case NFTNL_EXPR_CTR_BYTES:
51  *data_len = sizeof(ctr->bytes);
52  return &ctr->bytes;
53  case NFTNL_EXPR_CTR_PACKETS:
54  *data_len = sizeof(ctr->pkts);
55  return &ctr->pkts;
56  }
57  return NULL;
58 }
59 
60 static int nftnl_expr_counter_cb(const struct nlattr *attr, void *data)
61 {
62  const struct nlattr **tb = data;
63  int type = mnl_attr_get_type(attr);
64 
65  if (mnl_attr_type_valid(attr, NFTA_COUNTER_MAX) < 0)
66  return MNL_CB_OK;
67 
68  switch(type) {
69  case NFTA_COUNTER_BYTES:
70  case NFTA_COUNTER_PACKETS:
71  if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
72  abi_breakage();
73  break;
74  }
75 
76  tb[type] = attr;
77  return MNL_CB_OK;
78 }
79 
80 static void
81 nftnl_expr_counter_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
82 {
83  struct nftnl_expr_counter *ctr = nftnl_expr_data(e);
84 
85  if (e->flags & (1 << NFTNL_EXPR_CTR_BYTES))
86  mnl_attr_put_u64(nlh, NFTA_COUNTER_BYTES, htobe64(ctr->bytes));
87  if (e->flags & (1 << NFTNL_EXPR_CTR_PACKETS))
88  mnl_attr_put_u64(nlh, NFTA_COUNTER_PACKETS, htobe64(ctr->pkts));
89 }
90 
91 static int
92 nftnl_expr_counter_parse(struct nftnl_expr *e, struct nlattr *attr)
93 {
94  struct nftnl_expr_counter *ctr = nftnl_expr_data(e);
95  struct nlattr *tb[NFTA_COUNTER_MAX+1] = {};
96 
97  if (mnl_attr_parse_nested(attr, nftnl_expr_counter_cb, tb) < 0)
98  return -1;
99 
100  if (tb[NFTA_COUNTER_BYTES]) {
101  ctr->bytes = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_BYTES]));
102  e->flags |= (1 << NFTNL_EXPR_CTR_BYTES);
103  }
104  if (tb[NFTA_COUNTER_PACKETS]) {
105  ctr->pkts = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_PACKETS]));
106  e->flags |= (1 << NFTNL_EXPR_CTR_PACKETS);
107  }
108 
109  return 0;
110 }
111 
112 static int nftnl_expr_counter_snprintf(char *buf, size_t len,
113  uint32_t flags,
114  const struct nftnl_expr *e)
115 {
116  struct nftnl_expr_counter *ctr = nftnl_expr_data(e);
117 
118  return snprintf(buf, len, "pkts %"PRIu64" bytes %"PRIu64" ",
119  ctr->pkts, ctr->bytes);
120 }
121 
122 static struct attr_policy counter_attr_policy[__NFTNL_EXPR_CTR_MAX] = {
123  [NFTNL_EXPR_CTR_PACKETS] = { .maxlen = sizeof(uint64_t) },
124  [NFTNL_EXPR_CTR_BYTES] = { .maxlen = sizeof(uint64_t) },
125 };
126 
127 struct expr_ops expr_ops_counter = {
128  .name = "counter",
129  .alloc_len = sizeof(struct nftnl_expr_counter),
130  .nftnl_max_attr = __NFTNL_EXPR_CTR_MAX - 1,
131  .attr_policy = counter_attr_policy,
132  .set = nftnl_expr_counter_set,
133  .get = nftnl_expr_counter_get,
134  .parse = nftnl_expr_counter_parse,
135  .build = nftnl_expr_counter_build,
136  .output = nftnl_expr_counter_snprintf,
137 };