libnftnl  1.0.2
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 #include "expr_ops.h"
25 
27  uint64_t pkts;
28  uint64_t bytes;
29 };
30 
31 static int
32 nft_rule_expr_counter_set(struct nft_rule_expr *e, uint16_t type,
33  const void *data, uint32_t data_len)
34 {
35  struct nft_expr_counter *ctr = nft_expr_data(e);
36 
37  switch(type) {
38  case NFT_EXPR_CTR_BYTES:
39  ctr->bytes = *((uint64_t *)data);
40  break;
41  case NFT_EXPR_CTR_PACKETS:
42  ctr->pkts = *((uint64_t *)data);
43  break;
44  default:
45  return -1;
46  }
47  return 0;
48 }
49 
50 static const void *
51 nft_rule_expr_counter_get(const struct nft_rule_expr *e, uint16_t type,
52  uint32_t *data_len)
53 {
54  struct nft_expr_counter *ctr = nft_expr_data(e);
55 
56  switch(type) {
57  case NFT_EXPR_CTR_BYTES:
58  *data_len = sizeof(ctr->bytes);
59  return &ctr->bytes;
60  case NFT_EXPR_CTR_PACKETS:
61  *data_len = sizeof(ctr->pkts);
62  return &ctr->pkts;
63  }
64  return NULL;
65 }
66 
67 static int nft_rule_expr_counter_cb(const struct nlattr *attr, void *data)
68 {
69  const struct nlattr **tb = data;
70  int type = mnl_attr_get_type(attr);
71 
72  if (mnl_attr_type_valid(attr, NFTA_COUNTER_MAX) < 0)
73  return MNL_CB_OK;
74 
75  switch(type) {
76  case NFTA_COUNTER_BYTES:
77  case NFTA_COUNTER_PACKETS:
78  if (mnl_attr_validate(attr, MNL_TYPE_U64) < 0) {
79  perror("mnl_attr_validate");
80  return MNL_CB_ERROR;
81  }
82  break;
83  }
84 
85  tb[type] = attr;
86  return MNL_CB_OK;
87 }
88 
89 static void
90 nft_rule_expr_counter_build(struct nlmsghdr *nlh, struct nft_rule_expr *e)
91 {
92  struct nft_expr_counter *ctr = nft_expr_data(e);
93 
94  if (e->flags & (1 << NFT_EXPR_CTR_BYTES))
95  mnl_attr_put_u64(nlh, NFTA_COUNTER_BYTES, htobe64(ctr->bytes));
96  if (e->flags & (1 << NFT_EXPR_CTR_PACKETS))
97  mnl_attr_put_u64(nlh, NFTA_COUNTER_PACKETS, htobe64(ctr->pkts));
98 }
99 
100 static int
101 nft_rule_expr_counter_parse(struct nft_rule_expr *e, struct nlattr *attr)
102 {
103  struct nft_expr_counter *ctr = nft_expr_data(e);
104  struct nlattr *tb[NFTA_COUNTER_MAX+1] = {};
105 
106  if (mnl_attr_parse_nested(attr, nft_rule_expr_counter_cb, tb) < 0)
107  return -1;
108 
109  if (tb[NFTA_COUNTER_BYTES]) {
110  ctr->bytes = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_BYTES]));
111  e->flags |= (1 << NFT_EXPR_CTR_BYTES);
112  }
113  if (tb[NFTA_COUNTER_PACKETS]) {
114  ctr->pkts = be64toh(mnl_attr_get_u64(tb[NFTA_COUNTER_PACKETS]));
115  e->flags |= (1 << NFT_EXPR_CTR_PACKETS);
116  }
117 
118  return 0;
119 }
120 
121 static int
122 nft_rule_expr_counter_json_parse(struct nft_rule_expr *e, json_t *root,
123  struct nft_parse_err *err)
124 {
125 #ifdef JSON_PARSING
126  uint64_t uval64;
127 
128  if (nft_jansson_parse_val(root, "pkts", NFT_TYPE_U64, &uval64,
129  err) == 0)
130  nft_rule_expr_set_u64(e, NFT_EXPR_CTR_PACKETS, uval64);
131 
132  if (nft_jansson_parse_val(root, "bytes", NFT_TYPE_U64, &uval64,
133  err) == 0)
134  nft_rule_expr_set_u64(e, NFT_EXPR_CTR_BYTES, uval64);
135 
136  return 0;
137 #else
138  errno = EOPNOTSUPP;
139  return -1;
140 #endif
141 }
142 
143 static int
144 nft_rule_expr_counter_xml_parse(struct nft_rule_expr *e, mxml_node_t *tree,
145  struct nft_parse_err *err)
146 {
147 #ifdef XML_PARSING
148  uint64_t pkts, bytes;
149 
150  if (nft_mxml_num_parse(tree, "pkts", MXML_DESCEND_FIRST, BASE_DEC,
151  &pkts, NFT_TYPE_U64, NFT_XML_MAND, err) == 0)
152  nft_rule_expr_set_u64(e, NFT_EXPR_CTR_PACKETS, pkts);
153 
154  if (nft_mxml_num_parse(tree, "bytes", MXML_DESCEND_FIRST, BASE_DEC,
155  &bytes, NFT_TYPE_U64, NFT_XML_MAND, err) == 0)
156  nft_rule_expr_set_u64(e, NFT_EXPR_CTR_BYTES, bytes);
157 
158  return 0;
159 #else
160  errno = EOPNOTSUPP;
161  return -1;
162 #endif
163 }
164 static int nft_rule_expr_counter_snprintf_json(char *buf, size_t len,
165  struct nft_rule_expr *e)
166 {
167  int ret, size = len, offset = 0;
168  struct nft_expr_counter *ctr = nft_expr_data(e);
169 
170  if (e->flags & (1 << NFT_EXPR_CTR_PACKETS)) {
171  ret = snprintf(buf, len,"\"pkts\":%"PRIu64",", ctr->pkts);
172  SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
173  }
174  if (e->flags & (1 << NFT_EXPR_CTR_BYTES)) {
175  ret = snprintf(buf + offset, len, "\"bytes\":%"PRIu64",", ctr->bytes);
176  SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
177  }
178 
179  /* Remove the last comma characther */
180  if (offset > 0)
181  offset--;
182 
183  return offset;
184 }
185 
186 static int nft_rule_expr_counter_snprintf_xml(char *buf, size_t len,
187  struct nft_rule_expr *e)
188 {
189  int ret, size = len, offset = 0;
190  struct nft_expr_counter *ctr = nft_expr_data(e);
191 
192  if (e->flags & (1 << NFT_EXPR_CTR_PACKETS)) {
193  ret = snprintf(buf, len, "<pkts>%"PRIu64"</pkts>", ctr->pkts);
194  SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
195  }
196  if (e->flags & (1 << NFT_EXPR_CTR_BYTES)) {
197  ret = snprintf(buf + offset, len, "<bytes>%"PRIu64"</bytes>",
198  ctr->bytes);
199  SNPRINTF_BUFFER_SIZE(ret, size, len, offset);
200  }
201 
202  return offset;
203 }
204 
205 static int nft_rule_expr_counter_snprintf_default(char *buf, size_t len,
206  struct nft_rule_expr *e)
207 {
208  struct nft_expr_counter *ctr = nft_expr_data(e);
209 
210  return snprintf(buf, len, "pkts %"PRIu64" bytes %"PRIu64" ",
211  ctr->pkts, ctr->bytes);
212 }
213 
214 static int nft_rule_expr_counter_snprintf(char *buf, size_t len, uint32_t type,
215  uint32_t flags,
216  struct nft_rule_expr *e)
217 {
218  switch(type) {
219  case NFT_OUTPUT_DEFAULT:
220  return nft_rule_expr_counter_snprintf_default(buf, len, e);
221  case NFT_OUTPUT_XML:
222  return nft_rule_expr_counter_snprintf_xml(buf, len, e);
223  case NFT_OUTPUT_JSON:
224  return nft_rule_expr_counter_snprintf_json(buf, len, e);
225  default:
226  break;
227  }
228  return -1;
229 }
230 
231 struct expr_ops expr_ops_counter = {
232  .name = "counter",
233  .alloc_len = sizeof(struct nft_expr_counter),
234  .max_attr = NFTA_COUNTER_MAX,
235  .set = nft_rule_expr_counter_set,
236  .get = nft_rule_expr_counter_get,
237  .parse = nft_rule_expr_counter_parse,
238  .build = nft_rule_expr_counter_build,
239  .snprintf = nft_rule_expr_counter_snprintf,
240  .xml_parse = nft_rule_expr_counter_xml_parse,
241  .json_parse = nft_rule_expr_counter_json_parse,
242 };
243 
244 static void __init expr_counter_init(void)
245 {
246  nft_expr_ops_register(&expr_ops_counter);
247 }