1 /*
2 * Copyright (C) 2011 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17 /* NOTICE: This is a clean room re-implementation of libnl */
18
19 #include <errno.h>
20 #include <unistd.h>
21 #include <malloc.h>
22 #include <sys/time.h>
23 #include <sys/socket.h>
24 #include "netlink-types.h"
25
26 /* Join group */
nl_socket_add_membership(struct nl_sock * sk,int group)27 int nl_socket_add_membership(struct nl_sock *sk, int group)
28 {
29 return setsockopt(sk->s_fd, SOL_NETLINK,
30 NETLINK_ADD_MEMBERSHIP, &group, sizeof(group));
31 }
32
33 /* Allocate new netlink socket. */
_nl_socket_alloc(void)34 static struct nl_sock *_nl_socket_alloc(void)
35 {
36 struct nl_sock *sk;
37 struct timeval tv;
38 struct nl_cb *cb;
39
40 sk = (struct nl_sock *) malloc(sizeof(struct nl_sock));
41 if (!sk)
42 return NULL;
43 memset(sk, 0, sizeof(*sk));
44
45 /* Get current time */
46
47 if (gettimeofday(&tv, NULL))
48 goto fail;
49 else
50 sk->s_seq_next = (int) tv.tv_sec;
51
52 /* Create local socket */
53 sk->s_local.nl_family = AF_NETLINK;
54 sk->s_local.nl_pid = 0; /* Kernel fills in pid */
55 sk->s_local.nl_groups = 0; /* No groups */
56
57 /* Create peer socket */
58 sk->s_peer.nl_family = AF_NETLINK;
59 sk->s_peer.nl_pid = 0; /* Kernel */
60 sk->s_peer.nl_groups = 0; /* No groups */
61
62 return sk;
63 fail:
64 free(sk);
65 return NULL;
66 }
67
68 /* Allocate new netlink socket. */
nl_socket_alloc(void)69 struct nl_sock *nl_socket_alloc(void)
70 {
71 struct nl_sock *sk = _nl_socket_alloc();
72 struct nl_cb *cb;
73
74 if (!sk)
75 return NULL;
76
77 cb = nl_cb_alloc(NL_CB_DEFAULT);
78 if (!cb)
79 goto cb_fail;
80 sk->s_cb = cb;
81 return sk;
82 cb_fail:
83 free(sk);
84 return NULL;
85 }
86
87 /* Allocate new socket with custom callbacks. */
nl_socket_alloc_cb(struct nl_cb * cb)88 struct nl_sock *nl_socket_alloc_cb(struct nl_cb *cb)
89 {
90 struct nl_sock *sk = _nl_socket_alloc();
91
92 if (!sk)
93 return NULL;
94
95 sk->s_cb = cb;
96 nl_cb_get(cb);
97
98 return sk;
99 }
100
101 /* Free a netlink socket. */
nl_socket_free(struct nl_sock * sk)102 void nl_socket_free(struct nl_sock *sk)
103 {
104 nl_cb_put(sk->s_cb);
105 close(sk->s_fd);
106 free(sk);
107 }
108
109 /* Sets socket buffer size of netlink socket */
nl_socket_set_buffer_size(struct nl_sock * sk,int rxbuf,int txbuf)110 int nl_socket_set_buffer_size(struct nl_sock *sk, int rxbuf, int txbuf)
111 {
112 if (setsockopt(sk->s_fd, SOL_SOCKET, SO_SNDBUF, \
113 &rxbuf, (socklen_t) sizeof(rxbuf)))
114 goto error;
115
116 if (setsockopt(sk->s_fd, SOL_SOCKET, SO_RCVBUF, \
117 &txbuf, (socklen_t) sizeof(txbuf)))
118 goto error;
119
120 return 0;
121 error:
122 return -errno;
123
124 }
125
nl_socket_get_fd(struct nl_sock * sk)126 int nl_socket_get_fd(struct nl_sock *sk)
127 {
128 return sk->s_fd;
129 }
130
nl_socket_set_cb(struct nl_sock * sk,struct nl_cb * cb)131 void nl_socket_set_cb(struct nl_sock *sk, struct nl_cb *cb)
132 {
133 nl_cb_put(sk->s_cb);
134 sk->s_cb = cb;
135 nl_cb_get(cb);
136 }
137
nl_socket_get_cb(struct nl_sock * sk)138 struct nl_cb *nl_socket_get_cb(struct nl_sock *sk)
139 {
140 return nl_cb_get(sk->s_cb);
141 }
142