161e12104SWon Kang /* 261e12104SWon Kang * Copyright (c) 2012 GCT Semiconductor, Inc. All rights reserved. 361e12104SWon Kang * 461e12104SWon Kang * This software is licensed under the terms of the GNU General Public 561e12104SWon Kang * License version 2, as published by the Free Software Foundation, and 661e12104SWon Kang * may be copied, distributed, and modified under those terms. 761e12104SWon Kang * 861e12104SWon Kang * This program is distributed in the hope that it will be useful, 961e12104SWon Kang * but WITHOUT ANY WARRANTY; without even the implied warranty of 1061e12104SWon Kang * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 1161e12104SWon Kang * GNU General Public License for more details. 1261e12104SWon Kang */ 1361e12104SWon Kang 140ec473b5SJoe Perches #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt 150ec473b5SJoe Perches 1661e12104SWon Kang #include <linux/export.h> 1761e12104SWon Kang #include <linux/etherdevice.h> 1861e12104SWon Kang #include <linux/netlink.h> 1961e12104SWon Kang #include <asm/byteorder.h> 2061e12104SWon Kang #include <net/sock.h> 2161e12104SWon Kang 2261e12104SWon Kang #include "netlink_k.h" 2361e12104SWon Kang 2461e12104SWon Kang #if defined(DEFINE_MUTEX) 2561e12104SWon Kang static DEFINE_MUTEX(netlink_mutex); 2661e12104SWon Kang #else 2761e12104SWon Kang static struct semaphore netlink_mutex; 2861e12104SWon Kang #define mutex_lock(x) down(x) 2961e12104SWon Kang #define mutex_unlock(x) up(x) 3061e12104SWon Kang #endif 3161e12104SWon Kang 3261e12104SWon Kang #define ND_MAX_GROUP 30 3361e12104SWon Kang #define ND_IFINDEX_LEN sizeof(int) 3461e12104SWon Kang #define ND_NLMSG_SPACE(len) (NLMSG_SPACE(len) + ND_IFINDEX_LEN) 35a6708372SDaniel Ngu #define ND_NLMSG_DATA(nlh) ((void *)((char *)NLMSG_DATA(nlh) + \ 36a6708372SDaniel Ngu ND_IFINDEX_LEN)) 3761e12104SWon Kang #define ND_NLMSG_S_LEN(len) (len+ND_IFINDEX_LEN) 3861e12104SWon Kang #define ND_NLMSG_R_LEN(nlh) (nlh->nlmsg_len-ND_IFINDEX_LEN) 3961e12104SWon Kang #define ND_NLMSG_IFIDX(nlh) NLMSG_DATA(nlh) 4061e12104SWon Kang #define ND_MAX_MSG_LEN (1024 * 32) 4161e12104SWon Kang 4261e12104SWon Kang static void (*rcv_cb)(struct net_device *dev, u16 type, void *msg, int len); 4361e12104SWon Kang 4461e12104SWon Kang static void netlink_rcv_cb(struct sk_buff *skb) 4561e12104SWon Kang { 4661e12104SWon Kang struct nlmsghdr *nlh; 4761e12104SWon Kang struct net_device *dev; 4861e12104SWon Kang u32 mlen; 4961e12104SWon Kang void *msg; 5061e12104SWon Kang int ifindex; 5161e12104SWon Kang 5261e12104SWon Kang if (!rcv_cb) { 530ec473b5SJoe Perches pr_err("nl cb - unregistered\n"); 5461e12104SWon Kang return; 5561e12104SWon Kang } 5661e12104SWon Kang 5758419939SHimangi Saraogi if (skb->len < NLMSG_HDRLEN) { 580ec473b5SJoe Perches pr_err("nl cb - invalid skb length\n"); 5961e12104SWon Kang return; 6061e12104SWon Kang } 6161e12104SWon Kang 6261e12104SWon Kang nlh = (struct nlmsghdr *)skb->data; 6361e12104SWon Kang 6461e12104SWon Kang if (skb->len < nlh->nlmsg_len || nlh->nlmsg_len > ND_MAX_MSG_LEN) { 650ec473b5SJoe Perches pr_err("nl cb - invalid length (%d,%d)\n", 6661e12104SWon Kang skb->len, nlh->nlmsg_len); 6761e12104SWon Kang return; 6861e12104SWon Kang } 6961e12104SWon Kang 7061e12104SWon Kang memcpy(&ifindex, ND_NLMSG_IFIDX(nlh), ND_IFINDEX_LEN); 7161e12104SWon Kang msg = ND_NLMSG_DATA(nlh); 7261e12104SWon Kang mlen = ND_NLMSG_R_LEN(nlh); 7361e12104SWon Kang 7461e12104SWon Kang dev = dev_get_by_index(&init_net, ifindex); 7561e12104SWon Kang if (dev) { 7661e12104SWon Kang rcv_cb(dev, nlh->nlmsg_type, msg, mlen); 7761e12104SWon Kang dev_put(dev); 7861e12104SWon Kang } else { 790ec473b5SJoe Perches pr_err("nl cb - dev (%d) not found\n", ifindex); 8061e12104SWon Kang } 8161e12104SWon Kang } 8261e12104SWon Kang 8361e12104SWon Kang static void netlink_rcv(struct sk_buff *skb) 8461e12104SWon Kang { 8561e12104SWon Kang mutex_lock(&netlink_mutex); 8661e12104SWon Kang netlink_rcv_cb(skb); 8761e12104SWon Kang mutex_unlock(&netlink_mutex); 8861e12104SWon Kang } 8961e12104SWon Kang 9061e12104SWon Kang struct sock *netlink_init(int unit, 9161e12104SWon Kang void (*cb)(struct net_device *dev, u16 type, void *msg, int len)) 9261e12104SWon Kang { 9361e12104SWon Kang struct sock *sock; 9461e12104SWon Kang struct netlink_kernel_cfg cfg = { 9561e12104SWon Kang .input = netlink_rcv, 9661e12104SWon Kang }; 9761e12104SWon Kang 9861e12104SWon Kang #if !defined(DEFINE_MUTEX) 9961e12104SWon Kang init_MUTEX(&netlink_mutex); 10061e12104SWon Kang #endif 10161e12104SWon Kang 10261e12104SWon Kang sock = netlink_kernel_create(&init_net, unit, &cfg); 10361e12104SWon Kang 10461e12104SWon Kang if (sock) 10561e12104SWon Kang rcv_cb = cb; 10661e12104SWon Kang 10761e12104SWon Kang return sock; 10861e12104SWon Kang } 10961e12104SWon Kang 11061e12104SWon Kang void netlink_exit(struct sock *sock) 11161e12104SWon Kang { 11261e12104SWon Kang sock_release(sock->sk_socket); 11361e12104SWon Kang } 11461e12104SWon Kang 11561e12104SWon Kang int netlink_send(struct sock *sock, int group, u16 type, void *msg, int len) 11661e12104SWon Kang { 11761e12104SWon Kang static u32 seq; 11861e12104SWon Kang struct sk_buff *skb = NULL; 11961e12104SWon Kang struct nlmsghdr *nlh; 12061e12104SWon Kang int ret = 0; 12161e12104SWon Kang 12261e12104SWon Kang if (group > ND_MAX_GROUP) 12361e12104SWon Kang return -EINVAL; 12461e12104SWon Kang 12561e12104SWon Kang if (!netlink_has_listeners(sock, group+1)) 12661e12104SWon Kang return -ESRCH; 12761e12104SWon Kang 12861e12104SWon Kang skb = alloc_skb(NLMSG_SPACE(len), GFP_ATOMIC); 12961e12104SWon Kang if (!skb) 13061e12104SWon Kang return -ENOMEM; 13161e12104SWon Kang 13261e12104SWon Kang seq++; 13361e12104SWon Kang 13461e12104SWon Kang nlh = nlmsg_put(skb, 0, seq, type, len, 0); 13561e12104SWon Kang memcpy(NLMSG_DATA(nlh), msg, len); 13661e12104SWon Kang NETLINK_CB(skb).portid = 0; 13761e12104SWon Kang NETLINK_CB(skb).dst_group = 0; 13861e12104SWon Kang 13961e12104SWon Kang ret = netlink_broadcast(sock, skb, 0, group+1, GFP_ATOMIC); 14061e12104SWon Kang if (!ret) 14161e12104SWon Kang return len; 14261e12104SWon Kang 14361e12104SWon Kang if (ret != -ESRCH) 1440ec473b5SJoe Perches pr_err("nl broadcast g=%d, t=%d, l=%d, r=%d\n", 14561e12104SWon Kang group, type, len, ret); 14661e12104SWon Kang else if (netlink_has_listeners(sock, group+1)) 14761e12104SWon Kang return -EAGAIN; 14861e12104SWon Kang 14961e12104SWon Kang return ret; 15061e12104SWon Kang } 151