libnl  3.5.0
meta.c
1 /*
2  * lib/route/cls/ematch/meta.c Metadata Match
3  *
4  * This library is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation version 2.1
7  * of the License.
8  *
9  * Copyright (c) 2010-2013 Thomas Graf <tgraf@suug.ch>
10  */
11 
12 /**
13  * @ingroup ematch
14  * @defgroup em_meta Metadata Match
15  *
16  * @{
17  */
18 
19 #include <netlink-private/netlink.h>
20 #include <netlink-private/tc.h>
21 #include <netlink/netlink.h>
22 #include <netlink/route/cls/ematch.h>
23 #include <netlink/route/cls/ematch/meta.h>
24 #include <linux/tc_ematch/tc_em_meta.h>
25 
27 {
28  uint8_t mv_type;
29  uint8_t mv_shift;
30  uint16_t mv_id;
31  size_t mv_len;
32 };
33 
34 struct meta_data
35 {
36  struct rtnl_meta_value * left;
37  struct rtnl_meta_value * right;
38  uint8_t opnd;
39 };
40 
41 static struct rtnl_meta_value *meta_alloc(uint8_t type, uint16_t id,
42  uint8_t shift, void *data,
43  size_t len)
44 {
45  struct rtnl_meta_value *value;
46 
47  if (!(value = calloc(1, sizeof(*value) + len)))
48  return NULL;
49 
50  value->mv_type = type;
51  value->mv_id = id;
52  value->mv_shift = shift;
53  value->mv_len = len;
54 
55  if (len)
56  memcpy(value + 1, data, len);
57 
58  return value;
59 }
60 
61 struct rtnl_meta_value *rtnl_meta_value_alloc_int(uint64_t value)
62 {
63  return meta_alloc(TCF_META_TYPE_INT, TCF_META_ID_VALUE, 0, &value, 8);
64 }
65 
66 struct rtnl_meta_value *rtnl_meta_value_alloc_var(void *data, size_t len)
67 {
68  return meta_alloc(TCF_META_TYPE_VAR, TCF_META_ID_VALUE, 0, data, len);
69 }
70 
71 struct rtnl_meta_value *rtnl_meta_value_alloc_id(uint8_t type, uint16_t id,
72  uint8_t shift, uint64_t mask)
73 {
74  size_t masklen = 0;
75 
76  if (id > TCF_META_ID_MAX)
77  return NULL;
78 
79  if (mask) {
80  if (type == TCF_META_TYPE_VAR)
81  return NULL;
82 
83  masklen = 8;
84  }
85 
86  return meta_alloc(type, id, shift, &mask, masklen);
87 }
88 
89 void rtnl_meta_value_put(struct rtnl_meta_value *mv)
90 {
91  free(mv);
92 }
93 
94 void rtnl_ematch_meta_set_lvalue(struct rtnl_ematch *e, struct rtnl_meta_value *v)
95 {
96  struct meta_data *m = rtnl_ematch_data(e);
97  m->left = v;
98 }
99 
100 void rtnl_ematch_meta_set_rvalue(struct rtnl_ematch *e, struct rtnl_meta_value *v)
101 {
102  struct meta_data *m = rtnl_ematch_data(e);
103  m->right = v;
104 }
105 
106 void rtnl_ematch_meta_set_operand(struct rtnl_ematch *e, uint8_t opnd)
107 {
108  struct meta_data *m = rtnl_ematch_data(e);
109  m->opnd = opnd;
110 }
111 
112 static struct nla_policy meta_policy[TCA_EM_META_MAX+1] = {
113  [TCA_EM_META_HDR] = { .minlen = sizeof(struct tcf_meta_hdr) },
114  [TCA_EM_META_LVALUE] = { .minlen = 1, },
115  [TCA_EM_META_RVALUE] = { .minlen = 1, },
116 };
117 
118 static int meta_parse(struct rtnl_ematch *e, void *data, size_t len)
119 {
120  struct meta_data *m = rtnl_ematch_data(e);
121  struct nlattr *tb[TCA_EM_META_MAX+1];
122  struct rtnl_meta_value *v;
123  struct tcf_meta_hdr *hdr;
124  void *vdata = NULL;
125  size_t vlen = 0;
126  int err;
127 
128  if ((err = nla_parse(tb, TCA_EM_META_MAX, data, len, meta_policy)) < 0)
129  return err;
130 
131  if (!tb[TCA_EM_META_HDR])
132  return -NLE_MISSING_ATTR;
133 
134  hdr = nla_data(tb[TCA_EM_META_HDR]);
135 
136  if (tb[TCA_EM_META_LVALUE]) {
137  vdata = nla_data(tb[TCA_EM_META_LVALUE]);
138  vlen = nla_len(tb[TCA_EM_META_LVALUE]);
139  }
140 
141  v = meta_alloc(TCF_META_TYPE(hdr->left.kind),
142  TCF_META_ID(hdr->left.kind),
143  hdr->left.shift, vdata, vlen);
144  if (!v)
145  return -NLE_NOMEM;
146 
147  m->left = v;
148 
149  vlen = 0;
150  if (tb[TCA_EM_META_RVALUE]) {
151  vdata = nla_data(tb[TCA_EM_META_RVALUE]);
152  vlen = nla_len(tb[TCA_EM_META_RVALUE]);
153  }
154 
155  v = meta_alloc(TCF_META_TYPE(hdr->right.kind),
156  TCF_META_ID(hdr->right.kind),
157  hdr->right.shift, vdata, vlen);
158  if (!v) {
159  rtnl_meta_value_put(m->left);
160  return -NLE_NOMEM;
161  }
162 
163  m->right = v;
164  m->opnd = hdr->left.op;
165 
166  return 0;
167 }
168 
169 static const struct trans_tbl meta_int[] = {
170  __ADD(TCF_META_ID_RANDOM, random),
171  __ADD(TCF_META_ID_LOADAVG_0, loadavg_0),
172  __ADD(TCF_META_ID_LOADAVG_1, loadavg_1),
173  __ADD(TCF_META_ID_LOADAVG_2, loadavg_2),
174  __ADD(TCF_META_ID_DEV, dev),
175  __ADD(TCF_META_ID_PRIORITY, prio),
176  __ADD(TCF_META_ID_PROTOCOL, proto),
177  __ADD(TCF_META_ID_PKTTYPE, pkttype),
178  __ADD(TCF_META_ID_PKTLEN, pktlen),
179  __ADD(TCF_META_ID_DATALEN, datalen),
180  __ADD(TCF_META_ID_MACLEN, maclen),
181  __ADD(TCF_META_ID_NFMARK, mark),
182  __ADD(TCF_META_ID_TCINDEX, tcindex),
183  __ADD(TCF_META_ID_RTCLASSID, rtclassid),
184  __ADD(TCF_META_ID_RTIIF, rtiif),
185  __ADD(TCF_META_ID_SK_FAMILY, sk_family),
186  __ADD(TCF_META_ID_SK_STATE, sk_state),
187  __ADD(TCF_META_ID_SK_REUSE, sk_reuse),
188  __ADD(TCF_META_ID_SK_REFCNT, sk_refcnt),
189  __ADD(TCF_META_ID_SK_RCVBUF, sk_rcvbuf),
190  __ADD(TCF_META_ID_SK_SNDBUF, sk_sndbuf),
191  __ADD(TCF_META_ID_SK_SHUTDOWN, sk_sutdown),
192  __ADD(TCF_META_ID_SK_PROTO, sk_proto),
193  __ADD(TCF_META_ID_SK_TYPE, sk_type),
194  __ADD(TCF_META_ID_SK_RMEM_ALLOC, sk_rmem_alloc),
195  __ADD(TCF_META_ID_SK_WMEM_ALLOC, sk_wmem_alloc),
196  __ADD(TCF_META_ID_SK_WMEM_QUEUED, sk_wmem_queued),
197  __ADD(TCF_META_ID_SK_RCV_QLEN, sk_rcv_qlen),
198  __ADD(TCF_META_ID_SK_SND_QLEN, sk_snd_qlen),
199  __ADD(TCF_META_ID_SK_ERR_QLEN, sk_err_qlen),
200  __ADD(TCF_META_ID_SK_FORWARD_ALLOCS, sk_forward_allocs),
201  __ADD(TCF_META_ID_SK_ALLOCS, sk_allocs),
202  __ADD(__TCF_META_ID_SK_ROUTE_CAPS, sk_route_caps),
203  __ADD(TCF_META_ID_SK_HASH, sk_hash),
204  __ADD(TCF_META_ID_SK_LINGERTIME, sk_lingertime),
205  __ADD(TCF_META_ID_SK_ACK_BACKLOG, sk_ack_backlog),
206  __ADD(TCF_META_ID_SK_MAX_ACK_BACKLOG, sk_max_ack_backlog),
207  __ADD(TCF_META_ID_SK_PRIO, sk_prio),
208  __ADD(TCF_META_ID_SK_RCVLOWAT, sk_rcvlowat),
209  __ADD(TCF_META_ID_SK_RCVTIMEO, sk_rcvtimeo),
210  __ADD(TCF_META_ID_SK_SNDTIMEO, sk_sndtimeo),
211  __ADD(TCF_META_ID_SK_SENDMSG_OFF, sk_sendmsg_off),
212  __ADD(TCF_META_ID_SK_WRITE_PENDING, sk_write_pending),
213  __ADD(TCF_META_ID_VLAN_TAG, vlan),
214  __ADD(TCF_META_ID_RXHASH, rxhash),
215 };
216 
217 static char *int_id2str(int id, char *buf, size_t size)
218 {
219  return __type2str(id, buf, size, meta_int, ARRAY_SIZE(meta_int));
220 }
221 
222 static const struct trans_tbl meta_var[] = {
223  __ADD(TCF_META_ID_DEV,devname),
224  __ADD(TCF_META_ID_SK_BOUND_IF,sk_bound_if),
225 };
226 
227 static char *var_id2str(int id, char *buf, size_t size)
228 {
229  return __type2str(id, buf, size, meta_var, ARRAY_SIZE(meta_var));
230 }
231 
232 static void dump_value(struct rtnl_meta_value *v, struct nl_dump_params *p)
233 {
234  char buf[32];
235 
236  switch (v->mv_type) {
237  case TCF_META_TYPE_INT:
238  if (v->mv_id == TCF_META_ID_VALUE) {
239  nl_dump(p, "%u",
240  *(uint32_t *) (v + 1));
241  } else {
242  nl_dump(p, "%s",
243  int_id2str(v->mv_id, buf, sizeof(buf)));
244 
245  if (v->mv_shift)
246  nl_dump(p, " >> %u", v->mv_shift);
247 
248  if (v->mv_len == 4)
249  nl_dump(p, " & %#x", *(uint32_t *) (v + 1));
250  else if (v->mv_len == 8)
251  nl_dump(p, " & %#x", *(uint64_t *) (v + 1));
252  }
253  break;
254 
255  case TCF_META_TYPE_VAR:
256  if (v->mv_id == TCF_META_ID_VALUE) {
257  nl_dump(p, "%s", (char *) (v + 1));
258  } else {
259  nl_dump(p, "%s",
260  var_id2str(v->mv_id, buf, sizeof(buf)));
261 
262  if (v->mv_shift)
263  nl_dump(p, " >> %u", v->mv_shift);
264  }
265  break;
266  }
267 }
268 
269 static void meta_dump(struct rtnl_ematch *e, struct nl_dump_params *p)
270 {
271  struct meta_data *m = rtnl_ematch_data(e);
272  char buf[32];
273 
274  nl_dump(p, "meta(");
275  dump_value(m->left, p);
276 
277  nl_dump(p, " %s ", rtnl_ematch_opnd2txt(m->opnd, buf, sizeof(buf)));
278 
279  dump_value(m->right, p);
280  nl_dump(p, ")");
281 }
282 
283 static int meta_fill(struct rtnl_ematch *e, struct nl_msg *msg)
284 {
285  struct meta_data *m = rtnl_ematch_data(e);
286  struct tcf_meta_hdr hdr;
287 
288  if (!(m->left && m->right))
289  return -NLE_MISSING_ATTR;
290 
291  memset(&hdr, 0, sizeof(hdr));
292  hdr.left.kind = (m->left->mv_type << 12) & TCF_META_TYPE_MASK;
293  hdr.left.kind |= m->left->mv_id & TCF_META_ID_MASK;
294  hdr.left.shift = m->left->mv_shift;
295  hdr.left.op = m->opnd;
296  hdr.right.kind = (m->right->mv_type << 12) & TCF_META_TYPE_MASK;
297  hdr.right.kind |= m->right->mv_id & TCF_META_ID_MASK;
298 
299  NLA_PUT(msg, TCA_EM_META_HDR, sizeof(hdr), &hdr);
300 
301  if (m->left->mv_len)
302  NLA_PUT(msg, TCA_EM_META_LVALUE, m->left->mv_len, (m->left + 1));
303 
304  if (m->right->mv_len)
305  NLA_PUT(msg, TCA_EM_META_RVALUE, m->right->mv_len, (m->right + 1));
306 
307  return 0;
308 
309 nla_put_failure:
310  return -NLE_NOMEM;
311 }
312 
313 static void meta_free(struct rtnl_ematch *e)
314 {
315  struct meta_data *m = rtnl_ematch_data(e);
316  free(m->left);
317  free(m->right);
318 }
319 
320 static struct rtnl_ematch_ops meta_ops = {
321  .eo_kind = TCF_EM_META,
322  .eo_name = "meta",
323  .eo_minlen = sizeof(struct tcf_meta_hdr),
324  .eo_datalen = sizeof(struct meta_data),
325  .eo_parse = meta_parse,
326  .eo_dump = meta_dump,
327  .eo_fill = meta_fill,
328  .eo_free = meta_free,
329 };
330 
331 static void __init meta_init(void)
332 {
333  rtnl_ematch_register(&meta_ops);
334 }
335 
336 /** @} */
int nla_parse(struct nlattr *tb[], int maxtype, struct nlattr *head, int len, const struct nla_policy *policy)
Create attribute index based on a stream of attributes.
Definition: attr.c:243
Attribute validation policy.
Definition: attr.h:69
Definition: meta.c:34
#define NLA_PUT(msg, attrtype, attrlen, data)
Add unspecific attribute to netlink message.
Definition: attr.h:165
void * nla_data(const struct nlattr *nla)
Return pointer to the payload section.
Definition: attr.c:121
int rtnl_ematch_register(struct rtnl_ematch_ops *ops)
Register ematch module.
Definition: ematch.c:46
int nla_len(const struct nlattr *nla)
Return length of the payload .
Definition: attr.c:132
uint16_t minlen
Minimal length of payload required.
Definition: attr.h:74
Dumping parameters.
Definition: types.h:33
void nl_dump(struct nl_dump_params *params, const char *fmt,...)
Dump a formatted character string.
Definition: utils.c:962
Extended Match Operations.
Definition: ematch.h:33