1 /* 2 * File: pn_netlink.c 3 * 4 * Phonet netlink interface 5 * 6 * Copyright (C) 2008 Nokia Corporation. 7 * 8 * Contact: Remi Denis-Courmont <remi.denis-courmont@nokia.com> 9 * Original author: Sakari Ailus <sakari.ailus@nokia.com> 10 * 11 * This program is free software; you can redistribute it and/or 12 * modify it under the terms of the GNU General Public License 13 * version 2 as published by the Free Software Foundation. 14 * 15 * This program is distributed in the hope that it will be useful, but 16 * WITHOUT ANY WARRANTY; without even the implied warranty of 17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 18 * General Public License for more details. 19 * 20 * You should have received a copy of the GNU General Public License 21 * along with this program; if not, write to the Free Software 22 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 23 * 02110-1301 USA 24 */ 25 26 #include <linux/kernel.h> 27 #include <linux/netlink.h> 28 #include <linux/phonet.h> 29 #include <net/sock.h> 30 #include <net/phonet/pn_dev.h> 31 32 static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr, 33 u32 pid, u32 seq, int event); 34 35 void phonet_address_notify(int event, struct net_device *dev, u8 addr) 36 { 37 struct sk_buff *skb; 38 int err = -ENOBUFS; 39 40 skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + 41 nla_total_size(1), GFP_KERNEL); 42 if (skb == NULL) 43 goto errout; 44 err = fill_addr(skb, dev, addr, 0, 0, event); 45 if (err < 0) { 46 WARN_ON(err == -EMSGSIZE); 47 kfree_skb(skb); 48 goto errout; 49 } 50 rtnl_notify(skb, dev_net(dev), 0, 51 RTNLGRP_PHONET_IFADDR, NULL, GFP_KERNEL); 52 return; 53 errout: 54 if (err < 0) 55 rtnl_set_sk_err(dev_net(dev), RTNLGRP_PHONET_IFADDR, err); 56 } 57 58 static const struct nla_policy ifa_phonet_policy[IFA_MAX+1] = { 59 [IFA_LOCAL] = { .type = NLA_U8 }, 60 }; 61 62 static int addr_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *attr) 63 { 64 struct net *net = sock_net(skb->sk); 65 struct nlattr *tb[IFA_MAX+1]; 66 struct net_device *dev; 67 struct ifaddrmsg *ifm; 68 int err; 69 u8 pnaddr; 70 71 if (!capable(CAP_SYS_ADMIN)) 72 return -EPERM; 73 74 ASSERT_RTNL(); 75 76 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_phonet_policy); 77 if (err < 0) 78 return err; 79 80 ifm = nlmsg_data(nlh); 81 if (tb[IFA_LOCAL] == NULL) 82 return -EINVAL; 83 pnaddr = nla_get_u8(tb[IFA_LOCAL]); 84 if (pnaddr & 3) 85 /* Phonet addresses only have 6 high-order bits */ 86 return -EINVAL; 87 88 dev = __dev_get_by_index(net, ifm->ifa_index); 89 if (dev == NULL) 90 return -ENODEV; 91 92 if (nlh->nlmsg_type == RTM_NEWADDR) 93 err = phonet_address_add(dev, pnaddr); 94 else 95 err = phonet_address_del(dev, pnaddr); 96 if (!err) 97 phonet_address_notify(nlh->nlmsg_type, dev, pnaddr); 98 return err; 99 } 100 101 static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr, 102 u32 pid, u32 seq, int event) 103 { 104 struct ifaddrmsg *ifm; 105 struct nlmsghdr *nlh; 106 107 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*ifm), 0); 108 if (nlh == NULL) 109 return -EMSGSIZE; 110 111 ifm = nlmsg_data(nlh); 112 ifm->ifa_family = AF_PHONET; 113 ifm->ifa_prefixlen = 0; 114 ifm->ifa_flags = IFA_F_PERMANENT; 115 ifm->ifa_scope = RT_SCOPE_LINK; 116 ifm->ifa_index = dev->ifindex; 117 NLA_PUT_U8(skb, IFA_LOCAL, addr); 118 return nlmsg_end(skb, nlh); 119 120 nla_put_failure: 121 nlmsg_cancel(skb, nlh); 122 return -EMSGSIZE; 123 } 124 125 static int getaddr_dumpit(struct sk_buff *skb, struct netlink_callback *cb) 126 { 127 struct phonet_device_list *pndevs; 128 struct phonet_device *pnd; 129 int dev_idx = 0, dev_start_idx = cb->args[0]; 130 int addr_idx = 0, addr_start_idx = cb->args[1]; 131 132 pndevs = phonet_device_list(sock_net(skb->sk)); 133 spin_lock_bh(&pndevs->lock); 134 list_for_each_entry(pnd, &pndevs->list, list) { 135 u8 addr; 136 137 if (dev_idx > dev_start_idx) 138 addr_start_idx = 0; 139 if (dev_idx++ < dev_start_idx) 140 continue; 141 142 addr_idx = 0; 143 for (addr = find_first_bit(pnd->addrs, 64); addr < 64; 144 addr = find_next_bit(pnd->addrs, 64, 1+addr)) { 145 if (addr_idx++ < addr_start_idx) 146 continue; 147 148 if (fill_addr(skb, pnd->netdev, addr << 2, 149 NETLINK_CB(cb->skb).pid, 150 cb->nlh->nlmsg_seq, RTM_NEWADDR) < 0) 151 goto out; 152 } 153 } 154 155 out: 156 spin_unlock_bh(&pndevs->lock); 157 cb->args[0] = dev_idx; 158 cb->args[1] = addr_idx; 159 160 return skb->len; 161 } 162 163 int __init phonet_netlink_register(void) 164 { 165 int err = __rtnl_register(PF_PHONET, RTM_NEWADDR, addr_doit, NULL); 166 if (err) 167 return err; 168 169 /* Further __rtnl_register() cannot fail */ 170 __rtnl_register(PF_PHONET, RTM_DELADDR, addr_doit, NULL); 171 __rtnl_register(PF_PHONET, RTM_GETADDR, NULL, getaddr_dumpit); 172 return 0; 173 } 174