libnl: /data/src/libnl3/lib/route/route.c Source File

libnl 3.7.0

route.c
1 /* SPDX-License-Identifier: LGPL-2.1-only */
2 /*
3 * Copyright (c) 2003-2008 Thomas Graf <tgraf@suug.ch>
4 */
5
6 /**
7 * @ingroup rtnl
8 * @defgroup route Routing
9 * @brief
10 * @{
11 */
12
13 #include <netlink-private/netlink.h>
14 #include <netlink-private/nl-auto.h>
15 #include <netlink/netlink.h>
16 #include <netlink/cache.h>
17 #include <netlink/utils.h>
18 #include <netlink/data.h>
19 #include <netlink/route/rtnl.h>
20 #include <netlink/route/route.h>
21 #include <netlink/route/link.h>
22
23 static struct nl_cache_ops rtnl_route_ops;
24
25 static int route_msg_parser(struct nl_cache_ops *ops, struct sockaddr_nl *who,
26 struct nlmsghdr *nlh, struct nl_parser_param *pp)
27 {
28 struct rtnl_route *route;
29 int err;
30
31 if ((err = rtnl_route_parse(nlh, &route)) < 0)
32 return err;
33
34 err = pp->pp_cb((struct nl_object *) route, pp);
35
36 rtnl_route_put(route);
37 return err;
38 }
39
40 static int route_request_update(struct nl_cache *c, struct nl_sock *h)
41 {
42 struct rtmsg rhdr = {
43 .rtm_family = c->c_iarg1,
44 };
45
46 if (c->c_iarg2 & ROUTE_CACHE_CONTENT)
47 rhdr.rtm_flags |= RTM_F_CLONED;
48
49 return nl_send_simple(h, RTM_GETROUTE, NLM_F_DUMP, &rhdr, sizeof(rhdr));
50 }
51
52 /**
53 * @name Cache Management
54 * @{
55 */
56
57 /**
58 * Build a route cache holding all routes currently configured in the kernel
59 * @arg sk Netlink socket.
60 * @arg family Address family of routes to cover or AF_UNSPEC
61 * @arg flags Flags
62 * @arg result Result pointer
63 *
64 * Allocates a new cache, initializes it properly and updates it to
65 * contain all routes currently configured in the kernel.
66 *
67 * Valid flags:
68 * * ROUTE_CACHE_CONTENT - Cache will contain contents of routing cache
69 * instead of actual routes.
70 *
71 * @note The caller is responsible for destroying and freeing the
72 * cache after using it.
73 * @return 0 on success or a negative error code.
74 */
75 int rtnl_route_alloc_cache(struct nl_sock *sk, int family, int flags,
76 struct nl_cache **result)
77 {
78 struct nl_cache *cache;
79 int err;
80
81 if (!(cache = nl_cache_alloc(&rtnl_route_ops)))
82 return -NLE_NOMEM;
83
84 cache->c_iarg1 = family;
85 cache->c_iarg2 = flags;
86
87 if (sk && (err = nl_cache_refill(sk, cache)) < 0) {
88 free(cache);
89 return err;
90 }
91
92 *result = cache;
93 return 0;
94 }
95
96 /** @} */
97
98 /**
99 * @name Route Addition
100 * @{
101 */
102
103 static int build_route_msg(struct rtnl_route *tmpl, int cmd, int flags,
104 struct nl_msg **result)
105 {
106 struct nl_msg *msg;
107 int err;
108
109 if (!(msg = nlmsg_alloc_simple(cmd, flags)))
110 return -NLE_NOMEM;
111
112 if ((err = rtnl_route_build_msg(msg, tmpl)) < 0) {
113 nlmsg_free(msg);
114 return err;
115 }
116
117 *result = msg;
118 return 0;
119 }
120
121 int rtnl_route_build_add_request(struct rtnl_route *tmpl, int flags,
122 struct nl_msg **result)
123 {
124 return build_route_msg(tmpl, RTM_NEWROUTE, NLM_F_CREATE | flags,
125 result);
126 }
127
128 int rtnl_route_lookup(struct nl_sock *sk, struct nl_addr *dst,
129 struct rtnl_route **result)
130 {
131 _nl_auto_nl_msg struct nl_msg *msg = NULL;
132 _nl_auto_rtnl_route struct rtnl_route *tmpl = NULL;
133 struct nl_object *obj;
134 int err;
135
136 tmpl = rtnl_route_alloc();
137 rtnl_route_set_dst(tmpl, dst);
138 err = build_route_msg(tmpl, RTM_GETROUTE, 0, &msg);
139 if (err < 0)
140 return err;
141
142 err = nl_send_auto(sk, msg);
143 if (err < 0)
144 return err;
145
146 if ((err = nl_pickup(sk, route_msg_parser, &obj)) < 0)
147 return err;
148
149 *result = (struct rtnl_route *)obj;
150 wait_for_ack(sk);
151 return 0;
152 }
153
154 int rtnl_route_add(struct nl_sock *sk, struct rtnl_route *route, int flags)
155 {
156 struct nl_msg *msg;
157 int err;
158
159 if ((err = rtnl_route_build_add_request(route, flags, &msg)) < 0)
160 return err;
161
162 err = nl_send_auto_complete(sk, msg);
163 nlmsg_free(msg);
164 if (err < 0)
165 return err;
166
167 return wait_for_ack(sk);
168 }
169
170 int rtnl_route_build_del_request(struct rtnl_route *tmpl, int flags,
171 struct nl_msg **result)
172 {
173 return build_route_msg(tmpl, RTM_DELROUTE, flags, result);
174 }
175
176 int rtnl_route_delete(struct nl_sock *sk, struct rtnl_route *route, int flags)
177 {
178 struct nl_msg *msg;
179 int err;
180
181 if ((err = rtnl_route_build_del_request(route, flags, &msg)) < 0)
182 return err;
183
184 err = nl_send_auto_complete(sk, msg);
185 nlmsg_free(msg);
186 if (err < 0)
187 return err;
188
189 return wait_for_ack(sk);
190 }
191
192 /** @} */
193
194 static struct nl_af_group route_groups[] = {
195 { AF_INET, RTNLGRP_IPV4_ROUTE },
196 { AF_INET6, RTNLGRP_IPV6_ROUTE },
197 { AF_MPLS, RTNLGRP_MPLS_ROUTE },
198 { AF_DECnet, RTNLGRP_DECnet_ROUTE },
199 { END_OF_GROUP_LIST },
200 };
201
202 static struct nl_cache_ops rtnl_route_ops = {
203 .co_name = "route/route",
204 .co_hdrsize = sizeof(struct rtmsg),
205 .co_msgtypes = {
206 { RTM_NEWROUTE, NL_ACT_NEW, "new" },
207 { RTM_DELROUTE, NL_ACT_DEL, "del" },
208 { RTM_GETROUTE, NL_ACT_GET, "get" },
209 END_OF_MSGTYPES_LIST,
210 },
211 .co_protocol = NETLINK_ROUTE,
212 .co_groups = route_groups,
213 .co_request_update = route_request_update,
214 .co_msg_parser = route_msg_parser,
215 .co_obj_ops = &route_obj_ops,
216 };
217
218 static void __init route_init(void)
219 {
220 nl_cache_mngt_register(&rtnl_route_ops);
221 }
222
223 static void __exit route_exit(void)
224 {
225 nl_cache_mngt_unregister(&rtnl_route_ops);
226 }
227
228 /** @} */
nl_cache_mngt_unregister
int nl_cache_mngt_unregister(struct nl_cache_ops *ops)
Unregister a set of cache operations.
Definition: cache_mngt.c:281
nl_cache_mngt_register
int nl_cache_mngt_register(struct nl_cache_ops *ops)
Register a set of cache operations.
Definition: cache_mngt.c:246
nl_cache_refill
int nl_cache_refill(struct nl_sock *sk, struct nl_cache *cache)
(Re)fill a cache with the contents in the kernel.
Definition: cache.c:1035
nl_cache_alloc
struct nl_cache * nl_cache_alloc(struct nl_cache_ops *ops)
Allocate new cache.
Definition: cache.c:178
nlmsg_alloc_simple
struct nl_msg * nlmsg_alloc_simple(int nlmsgtype, int flags)
Allocate a new netlink message.
Definition: msg.c:341
nlmsg_free
void nlmsg_free(struct nl_msg *msg)
Release a reference from an netlink message.
Definition: msg.c:558
rtnl_route_alloc_cache
int rtnl_route_alloc_cache(struct nl_sock *sk, int family, int flags, struct nl_cache **result)
Build a route cache holding all routes currently configured in the kernel.
Definition: route.c:75
ROUTE_CACHE_CONTENT
#define ROUTE_CACHE_CONTENT
When passed to rtnl_route_alloc_cache() the cache will correspond to the contents of the routing cach...
Definition: route.h:27
nl_send_auto
int nl_send_auto(struct nl_sock *sk, struct nl_msg *msg)
Finalize and transmit Netlink message.
Definition: nl.c:510
nl_send_auto_complete
int nl_send_auto_complete(struct nl_sock *sk, struct nl_msg *msg)
Definition: nl.c:1241
nl_pickup
int nl_pickup(struct nl_sock *sk, int(*parser)(struct nl_cache_ops *, struct sockaddr_nl *, struct nlmsghdr *, struct nl_parser_param *), struct nl_object **result)
Pickup netlink answer, parse is and return object.
Definition: nl.c:1172
nl_send_simple
int nl_send_simple(struct nl_sock *sk, int type, int flags, void *buf, size_t size)
Construct and transmit a Netlink message.
Definition: nl.c:574