libnftnl  1.2.6
last.c
1 /*
2  * (C) 2016 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 
10 #include <stdio.h>
11 #include <stdint.h>
12 #include <arpa/inet.h>
13 #include <errno.h>
14 #include <inttypes.h>
15 
16 #include <linux/netfilter/nf_tables.h>
17 
18 #include "internal.h"
19 #include <libmnl/libmnl.h>
20 #include <libnftnl/expr.h>
21 #include <libnftnl/rule.h>
22 
24  uint64_t msecs;
25  uint32_t set;
26 };
27 
28 static int nftnl_expr_last_set(struct nftnl_expr *e, uint16_t type,
29  const void *data, uint32_t data_len)
30 {
31  struct nftnl_expr_last *last = nftnl_expr_data(e);
32 
33  switch (type) {
34  case NFTNL_EXPR_LAST_MSECS:
35  memcpy(&last->msecs, data, sizeof(last->msecs));
36  break;
37  case NFTNL_EXPR_LAST_SET:
38  memcpy(&last->set, data, sizeof(last->set));
39  break;
40  default:
41  return -1;
42  }
43  return 0;
44 }
45 
46 static const void *nftnl_expr_last_get(const struct nftnl_expr *e,
47  uint16_t type, uint32_t *data_len)
48 {
49  struct nftnl_expr_last *last = nftnl_expr_data(e);
50 
51  switch (type) {
52  case NFTNL_EXPR_LAST_MSECS:
53  *data_len = sizeof(last->msecs);
54  return &last->msecs;
55  case NFTNL_EXPR_LAST_SET:
56  *data_len = sizeof(last->set);
57  return &last->set;
58  }
59  return NULL;
60 }
61 
62 static int nftnl_expr_last_cb(const struct nlattr *attr, void *data)
63 {
64  int type = mnl_attr_get_type(attr);
65  const struct nlattr **tb = data;
66 
67  if (mnl_attr_type_valid(attr, NFTA_LAST_MAX) < 0)
68  return MNL_CB_OK;
69 
70  switch(type) {
71  case NFTA_LAST_MSECS:
72  if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0)
73  abi_breakage();
74  break;
75  case NFTA_LAST_SET:
76  if (mnl_attr_validate(attr, MNL_TYPE_U32) < 0)
77  abi_breakage();
78  break;
79  }
80 
81  tb[type] = attr;
82  return MNL_CB_OK;
83 }
84 
85 static void
86 nftnl_expr_last_build(struct nlmsghdr *nlh, const struct nftnl_expr *e)
87 {
88  struct nftnl_expr_last *last = nftnl_expr_data(e);
89 
90  if (e->flags & (1 << NFTNL_EXPR_LAST_MSECS))
91  mnl_attr_put_u64(nlh, NFTA_LAST_MSECS, htobe64(last->msecs));
92  if (e->flags & (1 << NFTNL_EXPR_LAST_SET))
93  mnl_attr_put_u32(nlh, NFTA_LAST_SET, htonl(last->set));
94 }
95 
96 static int
97 nftnl_expr_last_parse(struct nftnl_expr *e, struct nlattr *attr)
98 {
99  struct nftnl_expr_last *last = nftnl_expr_data(e);
100  struct nlattr *tb[NFTA_LAST_MAX + 1] = {};
101 
102  if (mnl_attr_parse_nested(attr, nftnl_expr_last_cb, tb) < 0)
103  return -1;
104 
105  if (tb[NFTA_LAST_MSECS]) {
106  last->msecs = be64toh(mnl_attr_get_u64(tb[NFTA_LAST_MSECS]));
107  e->flags |= (1 << NFTNL_EXPR_LAST_MSECS);
108  }
109  if (tb[NFTA_LAST_SET]) {
110  last->set = ntohl(mnl_attr_get_u32(tb[NFTA_LAST_SET]));
111  e->flags |= (1 << NFTNL_EXPR_LAST_SET);
112  }
113 
114  return 0;
115 }
116 
117 static int nftnl_expr_last_snprintf(char *buf, size_t len,
118  uint32_t flags,
119  const struct nftnl_expr *e)
120 {
121  struct nftnl_expr_last *last = nftnl_expr_data(e);
122 
123  if (!last->set)
124  return snprintf(buf, len, "never ");
125 
126  return snprintf(buf, len, "%"PRIu64" ", last->msecs);
127 }
128 
129 struct expr_ops expr_ops_last = {
130  .name = "last",
131  .alloc_len = sizeof(struct nftnl_expr_last),
132  .max_attr = NFTA_LAST_MAX,
133  .set = nftnl_expr_last_set,
134  .get = nftnl_expr_last_get,
135  .parse = nftnl_expr_last_parse,
136  .build = nftnl_expr_last_build,
137  .output = nftnl_expr_last_snprintf,
138 };