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/mutex.h>
18 #include <linux/etherdevice.h>
19 #include <linux/netlink.h>
20 #include <asm/byteorder.h>
23 #include "netlink_k.h"
25 static DEFINE_MUTEX(netlink_mutex);
27 #define ND_MAX_GROUP 30
28 #define ND_IFINDEX_LEN sizeof(int)
29 #define ND_NLMSG_SPACE(len) (NLMSG_SPACE(len) + ND_IFINDEX_LEN)
30 #define ND_NLMSG_DATA(nlh) ((void *)((char *)NLMSG_DATA(nlh) + \
32 #define ND_NLMSG_S_LEN(len) (len + ND_IFINDEX_LEN)
33 #define ND_NLMSG_R_LEN(nlh) (nlh->nlmsg_len - ND_IFINDEX_LEN)
34 #define ND_NLMSG_IFIDX(nlh) NLMSG_DATA(nlh)
35 #define ND_MAX_MSG_LEN (1024 * 32)
37 static void (*rcv_cb)(struct net_device *dev, u16 type, void *msg, int len);
39 static void netlink_rcv_cb(struct sk_buff *skb)
42 struct net_device *dev;
48 pr_err("nl cb - unregistered\n");
52 if (skb->len < NLMSG_HDRLEN) {
53 pr_err("nl cb - invalid skb length\n");
57 nlh = (struct nlmsghdr *)skb->data;
59 if (skb->len < nlh->nlmsg_len || nlh->nlmsg_len > ND_MAX_MSG_LEN) {
60 pr_err("nl cb - invalid length (%d,%d)\n",
61 skb->len, nlh->nlmsg_len);
65 memcpy(&ifindex, ND_NLMSG_IFIDX(nlh), ND_IFINDEX_LEN);
66 msg = ND_NLMSG_DATA(nlh);
67 mlen = ND_NLMSG_R_LEN(nlh);
69 dev = dev_get_by_index(&init_net, ifindex);
71 rcv_cb(dev, nlh->nlmsg_type, msg, mlen);
74 pr_err("nl cb - dev (%d) not found\n", ifindex);
78 static void netlink_rcv(struct sk_buff *skb)
80 mutex_lock(&netlink_mutex);
82 mutex_unlock(&netlink_mutex);
85 struct sock *netlink_init(int unit,
86 void (*cb)(struct net_device *dev, u16 type,
90 struct netlink_kernel_cfg cfg = {
94 sock = netlink_kernel_create(&init_net, unit, &cfg);
102 int netlink_send(struct sock *sock, int group, u16 type, void *msg, int len)
105 struct sk_buff *skb = NULL;
106 struct nlmsghdr *nlh;
109 if (group > ND_MAX_GROUP)
112 if (!netlink_has_listeners(sock, group + 1))
115 skb = alloc_skb(NLMSG_SPACE(len), GFP_ATOMIC);
121 nlh = nlmsg_put(skb, 0, seq, type, len, 0);
122 memcpy(NLMSG_DATA(nlh), msg, len);
123 NETLINK_CB(skb).portid = 0;
124 NETLINK_CB(skb).dst_group = 0;
126 ret = netlink_broadcast(sock, skb, 0, group + 1, GFP_ATOMIC);
131 pr_err("nl broadcast g=%d, t=%d, l=%d, r=%d\n",
132 group, type, len, ret);
133 else if (netlink_has_listeners(sock, group + 1))