2 * Copyright (c) 2012 GCT Semiconductor, Inc. All rights reserved.
4 * This software is licensed under the terms of the GNU General Public
5 * License version 2, as published by the Free Software Foundation, and
6 * may be copied, distributed, and modified under those terms.
8 * This program is distributed in the hope that it will be useful,
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11 * GNU General Public License for more details.
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16 #include <linux/export.h>
17 #include <linux/etherdevice.h>
18 #include <linux/netlink.h>
19 #include <asm/byteorder.h>
22 #include "netlink_k.h"
24 #if defined(DEFINE_MUTEX)
25 static DEFINE_MUTEX(netlink_mutex
);
27 static struct semaphore netlink_mutex
;
28 #define mutex_lock(x) down(x)
29 #define mutex_unlock(x) up(x)
32 #define ND_MAX_GROUP 30
33 #define ND_IFINDEX_LEN sizeof(int)
34 #define ND_NLMSG_SPACE(len) (NLMSG_SPACE(len) + ND_IFINDEX_LEN)
35 #define ND_NLMSG_DATA(nlh) ((void *)((char *)NLMSG_DATA(nlh) + ND_IFINDEX_LEN))
36 #define ND_NLMSG_S_LEN(len) (len+ND_IFINDEX_LEN)
37 #define ND_NLMSG_R_LEN(nlh) (nlh->nlmsg_len-ND_IFINDEX_LEN)
38 #define ND_NLMSG_IFIDX(nlh) NLMSG_DATA(nlh)
39 #define ND_MAX_MSG_LEN (1024 * 32)
41 static void (*rcv_cb
)(struct net_device
*dev
, u16 type
, void *msg
, int len
);
43 static void netlink_rcv_cb(struct sk_buff
*skb
)
46 struct net_device
*dev
;
52 pr_err("nl cb - unregistered\n");
56 if (skb
->len
< NLMSG_SPACE(0)) {
57 pr_err("nl cb - invalid skb length\n");
61 nlh
= (struct nlmsghdr
*)skb
->data
;
63 if (skb
->len
< nlh
->nlmsg_len
|| nlh
->nlmsg_len
> ND_MAX_MSG_LEN
) {
64 pr_err("nl cb - invalid length (%d,%d)\n",
65 skb
->len
, nlh
->nlmsg_len
);
69 memcpy(&ifindex
, ND_NLMSG_IFIDX(nlh
), ND_IFINDEX_LEN
);
70 msg
= ND_NLMSG_DATA(nlh
);
71 mlen
= ND_NLMSG_R_LEN(nlh
);
73 dev
= dev_get_by_index(&init_net
, ifindex
);
75 rcv_cb(dev
, nlh
->nlmsg_type
, msg
, mlen
);
78 pr_err("nl cb - dev (%d) not found\n", ifindex
);
82 static void netlink_rcv(struct sk_buff
*skb
)
84 mutex_lock(&netlink_mutex
);
86 mutex_unlock(&netlink_mutex
);
89 struct sock
*netlink_init(int unit
,
90 void (*cb
)(struct net_device
*dev
, u16 type
, void *msg
, int len
))
93 struct netlink_kernel_cfg cfg
= {
97 #if !defined(DEFINE_MUTEX)
98 init_MUTEX(&netlink_mutex
);
101 sock
= netlink_kernel_create(&init_net
, unit
, &cfg
);
109 void netlink_exit(struct sock
*sock
)
111 sock_release(sock
->sk_socket
);
114 int netlink_send(struct sock
*sock
, int group
, u16 type
, void *msg
, int len
)
117 struct sk_buff
*skb
= NULL
;
118 struct nlmsghdr
*nlh
;
121 if (group
> ND_MAX_GROUP
)
124 if (!netlink_has_listeners(sock
, group
+1))
127 skb
= alloc_skb(NLMSG_SPACE(len
), GFP_ATOMIC
);
133 nlh
= nlmsg_put(skb
, 0, seq
, type
, len
, 0);
134 memcpy(NLMSG_DATA(nlh
), msg
, len
);
135 NETLINK_CB(skb
).portid
= 0;
136 NETLINK_CB(skb
).dst_group
= 0;
138 ret
= netlink_broadcast(sock
, skb
, 0, group
+1, GFP_ATOMIC
);
143 pr_err("nl broadcast g=%d, t=%d, l=%d, r=%d\n",
144 group
, type
, len
, ret
);
145 else if (netlink_has_listeners(sock
, group
+1))