libnl  3.7.0
vrf.c
1 /* SPDX-License-Identifier: LGPL-2.1-only */
2 /*
3  * Copyright (c) 2015 Cumulus Networks. All rights reserved.
4  * Copyright (c) 2015 David Ahern <dsa@cumulusnetworks.com>
5  */
6 
7 /**
8  * @ingroup link
9  * @defgroup vrf VRF
10  * Virtual Routing and Forwarding link module
11  *
12  * @details
13  * \b Link Type Name: "vrf"
14  *
15  * @route_doc{link_vrf, VRF Documentation}
16  *
17  * @{
18  */
19 
20 #include <netlink-private/netlink.h>
21 #include <netlink/netlink.h>
22 #include <netlink/attr.h>
23 #include <netlink/utils.h>
24 #include <netlink/object.h>
25 #include <netlink/route/rtnl.h>
26 #include <netlink-private/route/link/api.h>
27 #include <netlink/route/link/vrf.h>
28 
29 #include <linux/if_link.h>
30 #include <linux-private/linux/rtnetlink.h>
31 
32 #define VRF_TABLE_ID_MAX RT_TABLE_MAX
33 
34 /** @cond SKIP */
35 #define VRF_HAS_TABLE_ID (1<<0)
36 
37 struct vrf_info {
38  uint32_t table_id;
39  uint32_t vi_mask;
40 };
41 
42 /** @endcond */
43 
44 static struct nla_policy vrf_policy[IFLA_VRF_MAX + 1] = {
45  [IFLA_VRF_TABLE] = { .type = NLA_U32 },
46 };
47 
48 static int vrf_alloc(struct rtnl_link *link)
49 {
50  struct vrf_info *vi;
51 
52  if (link->l_info) {
53  memset(link->l_info, 0, sizeof (*vi));
54  return 0;
55  }
56 
57  if ((vi = calloc(1, sizeof(*vi))) == NULL)
58  return -NLE_NOMEM;
59 
60  link->l_info = vi;
61 
62  return 0;
63 }
64 
65 static int vrf_parse(struct rtnl_link *link, struct nlattr *data,
66  struct nlattr *xstats)
67 {
68  struct nlattr *tb[IFLA_VRF_MAX+1];
69  struct vrf_info *vi;
70  int err;
71 
72  NL_DBG(3, "Parsing VRF link info");
73 
74  if ((err = nla_parse_nested(tb, IFLA_VRF_MAX, data, vrf_policy)) < 0)
75  goto errout;
76 
77  if ((err = vrf_alloc(link)) < 0)
78  goto errout;
79 
80  vi = link->l_info;
81 
82  if (tb[IFLA_VRF_TABLE]) {
83  vi->table_id = nla_get_u32(tb[IFLA_VRF_TABLE]);
84  vi->vi_mask |= VRF_HAS_TABLE_ID;
85  }
86 
87  err = 0;
88 
89 errout:
90  return err;
91 }
92 
93 static void vrf_free(struct rtnl_link *link)
94 {
95  free(link->l_info);
96  link->l_info = NULL;
97 }
98 
99 static int vrf_clone(struct rtnl_link *dst, struct rtnl_link *src)
100 {
101  struct vrf_info *vdst, *vsrc = src->l_info;
102  int err;
103 
104  dst->l_info = NULL;
105  if ((err = rtnl_link_set_type(dst, "vrf")) < 0)
106  return err;
107  vdst = dst->l_info;
108 
109  BUG_ON(!vdst || !vsrc);
110 
111  memcpy(vdst, vsrc, sizeof(struct vrf_info));
112 
113  return 0;
114 }
115 
116 static int vrf_put_attrs(struct nl_msg *msg, struct rtnl_link *link)
117 {
118  struct vrf_info *vi = link->l_info;
119  struct nlattr *data;
120 
121  if (!(data = nla_nest_start(msg, IFLA_INFO_DATA)))
122  return -NLE_NOMEM;
123 
124  if (vi->vi_mask & VRF_HAS_TABLE_ID) {
125  NLA_PUT_U32(msg, IFLA_VRF_TABLE, vi->table_id);
126  }
127 
128  nla_nest_end(msg, data);
129 
130 nla_put_failure:
131 
132  return 0;
133 }
134 
135 static void vrf_dump(struct rtnl_link *link, struct nl_dump_params *p)
136 {
137  struct vrf_info *vi = link->l_info;
138 
139  if (vi->vi_mask & VRF_HAS_TABLE_ID) {
140  nl_dump(p, "table-id %u", vi->table_id);
141  }
142 }
143 
144 static struct rtnl_link_info_ops vrf_info_ops = {
145  .io_name = "vrf",
146  .io_alloc = vrf_alloc,
147  .io_parse = vrf_parse,
148  .io_dump = {
149  [NL_DUMP_LINE] = vrf_dump,
150  [NL_DUMP_DETAILS] = vrf_dump,
151  },
152  .io_clone = vrf_clone,
153  .io_put_attrs = vrf_put_attrs,
154  .io_free = vrf_free,
155 };
156 
157 /** @cond SKIP */
158 #define IS_VRF_LINK_ASSERT(link) \
159  if ((link)->l_info_ops != &vrf_info_ops) { \
160  APPBUG("Link is not a VRF link. set type \"vrf\" first."); \
161  return -NLE_OPNOTSUPP; \
162  }
163 /** @endcond */
164 
165 /**
166  * @name VRF Object
167  * @{
168  */
169 
170 /**
171  * Allocate link object of type VRF
172  *
173  * @return Allocated link object or NULL.
174  */
176 {
177  struct rtnl_link *link;
178 
179  if (!(link = rtnl_link_alloc()))
180  return NULL;
181 
182  if (rtnl_link_set_type(link, "vrf") < 0) {
183  rtnl_link_put(link);
184  return NULL;
185  }
186 
187  return link;
188 }
189 
190 /**
191  * Check if link is a VRF link
192  * @arg link Link object
193  *
194  * @return True if link is a VRF link, otherwise false is returned.
195  */
196 int rtnl_link_is_vrf(struct rtnl_link *link)
197 {
198  return link->l_info_ops && !strcmp(link->l_info_ops->io_name, "vrf");
199 }
200 
201 /**
202  * Get VRF table id
203  * @arg link Link object
204  * @arg id Pointer to store table identifier
205  *
206  * @return 0 on success or a negative error code
207  */
208 int rtnl_link_vrf_get_tableid(struct rtnl_link *link, uint32_t *id)
209 {
210  struct vrf_info *vi = link->l_info;
211 
212  IS_VRF_LINK_ASSERT(link);
213  if(!id)
214  return -NLE_INVAL;
215 
216  if (vi->vi_mask & VRF_HAS_TABLE_ID)
217  *id = vi->table_id;
218  else
219  return -NLE_AGAIN;
220 
221  return 0;
222 }
223 
224 /**
225  * Set VRF table id
226  * @arg link Link object
227  * @arg id Table identifier associated with VRF link
228  *
229  * @return 0 on success or a negative error code
230  */
231 int rtnl_link_vrf_set_tableid(struct rtnl_link *link, uint32_t id)
232 {
233  struct vrf_info *vi = link->l_info;
234 
235  IS_VRF_LINK_ASSERT(link);
236 
237  _NL_STATIC_ASSERT(VRF_TABLE_ID_MAX == UINT32_MAX);
238 
239  vi->table_id = id;
240  vi->vi_mask |= VRF_HAS_TABLE_ID;
241 
242  return 0;
243 }
244 
245 /** @} */
246 
247 static void __init vrf_init(void)
248 {
249  rtnl_link_register_info(&vrf_info_ops);
250 }
251 
252 static void __exit vrf_exit(void)
253 {
254  rtnl_link_unregister_info(&vrf_info_ops);
255 }
256 
257 /** @} */
uint32_t nla_get_u32(const struct nlattr *nla)
Return payload of 32 bit integer attribute.
Definition: attr.c:699
#define NLA_PUT_U32(msg, attrtype, value)
Add 32 bit integer attribute to netlink message.
Definition: attr.h:230
struct nlattr * nla_nest_start(struct nl_msg *msg, int attrtype)
Start a new level of nested attributes.
Definition: attr.c:895
int nla_parse_nested(struct nlattr *tb[], int maxtype, struct nlattr *nla, const struct nla_policy *policy)
Create attribute index based on nested attribute.
Definition: attr.c:1013
int nla_nest_end(struct nl_msg *msg, struct nlattr *start)
Finalize nesting of attributes.
Definition: attr.c:958
@ NLA_U32
32 bit integer
Definition: attr.h:37
void nl_dump(struct nl_dump_params *params, const char *fmt,...)
Dump a formatted character string.
Definition: utils.c:955
@ NL_DUMP_LINE
Dump object briefly on one line.
Definition: types.h:16
@ NL_DUMP_DETAILS
Dump all attributes but no statistics.
Definition: types.h:17
int rtnl_link_is_vrf(struct rtnl_link *link)
Check if link is a VRF link.
Definition: vrf.c:196
int rtnl_link_vrf_set_tableid(struct rtnl_link *link, uint32_t id)
Set VRF table id.
Definition: vrf.c:231
int rtnl_link_vrf_get_tableid(struct rtnl_link *link, uint32_t *id)
Get VRF table id.
Definition: vrf.c:208
struct rtnl_link * rtnl_link_vrf_alloc(void)
Allocate link object of type VRF.
Definition: vrf.c:175
Dumping parameters.
Definition: types.h:28
Attribute validation policy.
Definition: attr.h:63
uint16_t type
Type of attribute or NLA_UNSPEC.
Definition: attr.h:65