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 <linux/slab.h> 30 #include <net/sock.h> 31 #include <net/phonet/pn_dev.h> 32 33 /* Device address handling */ 34 35 static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr, 36 u32 pid, u32 seq, int event); 37 38 void phonet_address_notify(int event, struct net_device *dev, u8 addr) 39 { 40 struct sk_buff *skb; 41 int err = -ENOBUFS; 42 43 skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + 44 nla_total_size(1), GFP_KERNEL); 45 if (skb == NULL) 46 goto errout; 47 err = fill_addr(skb, dev, addr, 0, 0, event); 48 if (err < 0) { 49 WARN_ON(err == -EMSGSIZE); 50 kfree_skb(skb); 51 goto errout; 52 } 53 rtnl_notify(skb, dev_net(dev), 0, 54 RTNLGRP_PHONET_IFADDR, NULL, GFP_KERNEL); 55 return; 56 errout: 57 rtnl_set_sk_err(dev_net(dev), RTNLGRP_PHONET_IFADDR, err); 58 } 59 60 static const struct nla_policy ifa_phonet_policy[IFA_MAX+1] = { 61 [IFA_LOCAL] = { .type = NLA_U8 }, 62 }; 63 64 static int addr_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *attr) 65 { 66 struct net *net = sock_net(skb->sk); 67 struct nlattr *tb[IFA_MAX+1]; 68 struct net_device *dev; 69 struct ifaddrmsg *ifm; 70 int err; 71 u8 pnaddr; 72 73 if (!capable(CAP_SYS_ADMIN)) 74 return -EPERM; 75 76 ASSERT_RTNL(); 77 78 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_phonet_policy); 79 if (err < 0) 80 return err; 81 82 ifm = nlmsg_data(nlh); 83 if (tb[IFA_LOCAL] == NULL) 84 return -EINVAL; 85 pnaddr = nla_get_u8(tb[IFA_LOCAL]); 86 if (pnaddr & 3) 87 /* Phonet addresses only have 6 high-order bits */ 88 return -EINVAL; 89 90 dev = __dev_get_by_index(net, ifm->ifa_index); 91 if (dev == NULL) 92 return -ENODEV; 93 94 if (nlh->nlmsg_type == RTM_NEWADDR) 95 err = phonet_address_add(dev, pnaddr); 96 else 97 err = phonet_address_del(dev, pnaddr); 98 if (!err) 99 phonet_address_notify(nlh->nlmsg_type, dev, pnaddr); 100 return err; 101 } 102 103 static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr, 104 u32 pid, u32 seq, int event) 105 { 106 struct ifaddrmsg *ifm; 107 struct nlmsghdr *nlh; 108 109 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*ifm), 0); 110 if (nlh == NULL) 111 return -EMSGSIZE; 112 113 ifm = nlmsg_data(nlh); 114 ifm->ifa_family = AF_PHONET; 115 ifm->ifa_prefixlen = 0; 116 ifm->ifa_flags = IFA_F_PERMANENT; 117 ifm->ifa_scope = RT_SCOPE_LINK; 118 ifm->ifa_index = dev->ifindex; 119 NLA_PUT_U8(skb, IFA_LOCAL, addr); 120 return nlmsg_end(skb, nlh); 121 122 nla_put_failure: 123 nlmsg_cancel(skb, nlh); 124 return -EMSGSIZE; 125 } 126 127 static int getaddr_dumpit(struct sk_buff *skb, struct netlink_callback *cb) 128 { 129 struct phonet_device_list *pndevs; 130 struct phonet_device *pnd; 131 int dev_idx = 0, dev_start_idx = cb->args[0]; 132 int addr_idx = 0, addr_start_idx = cb->args[1]; 133 134 pndevs = phonet_device_list(sock_net(skb->sk)); 135 rcu_read_lock(); 136 list_for_each_entry_rcu(pnd, &pndevs->list, list) { 137 u8 addr; 138 139 if (dev_idx > dev_start_idx) 140 addr_start_idx = 0; 141 if (dev_idx++ < dev_start_idx) 142 continue; 143 144 addr_idx = 0; 145 for_each_set_bit(addr, pnd->addrs, 64) { 146 if (addr_idx++ < addr_start_idx) 147 continue; 148 149 if (fill_addr(skb, pnd->netdev, addr << 2, 150 NETLINK_CB(cb->skb).pid, 151 cb->nlh->nlmsg_seq, RTM_NEWADDR) < 0) 152 goto out; 153 } 154 } 155 156 out: 157 rcu_read_unlock(); 158 cb->args[0] = dev_idx; 159 cb->args[1] = addr_idx; 160 161 return skb->len; 162 } 163 164 /* Routes handling */ 165 166 static int fill_route(struct sk_buff *skb, struct net_device *dev, u8 dst, 167 u32 pid, u32 seq, int event) 168 { 169 struct rtmsg *rtm; 170 struct nlmsghdr *nlh; 171 172 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*rtm), 0); 173 if (nlh == NULL) 174 return -EMSGSIZE; 175 176 rtm = nlmsg_data(nlh); 177 rtm->rtm_family = AF_PHONET; 178 rtm->rtm_dst_len = 6; 179 rtm->rtm_src_len = 0; 180 rtm->rtm_tos = 0; 181 rtm->rtm_table = RT_TABLE_MAIN; 182 rtm->rtm_protocol = RTPROT_STATIC; 183 rtm->rtm_scope = RT_SCOPE_UNIVERSE; 184 rtm->rtm_type = RTN_UNICAST; 185 rtm->rtm_flags = 0; 186 NLA_PUT_U8(skb, RTA_DST, dst); 187 NLA_PUT_U32(skb, RTA_OIF, dev->ifindex); 188 return nlmsg_end(skb, nlh); 189 190 nla_put_failure: 191 nlmsg_cancel(skb, nlh); 192 return -EMSGSIZE; 193 } 194 195 void rtm_phonet_notify(int event, struct net_device *dev, u8 dst) 196 { 197 struct sk_buff *skb; 198 int err = -ENOBUFS; 199 200 skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + 201 nla_total_size(1) + nla_total_size(4), GFP_KERNEL); 202 if (skb == NULL) 203 goto errout; 204 err = fill_route(skb, dev, dst, 0, 0, event); 205 if (err < 0) { 206 WARN_ON(err == -EMSGSIZE); 207 kfree_skb(skb); 208 goto errout; 209 } 210 rtnl_notify(skb, dev_net(dev), 0, 211 RTNLGRP_PHONET_ROUTE, NULL, GFP_KERNEL); 212 return; 213 errout: 214 rtnl_set_sk_err(dev_net(dev), RTNLGRP_PHONET_ROUTE, err); 215 } 216 217 static const struct nla_policy rtm_phonet_policy[RTA_MAX+1] = { 218 [RTA_DST] = { .type = NLA_U8 }, 219 [RTA_OIF] = { .type = NLA_U32 }, 220 }; 221 222 static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *attr) 223 { 224 struct net *net = sock_net(skb->sk); 225 struct nlattr *tb[RTA_MAX+1]; 226 struct net_device *dev; 227 struct rtmsg *rtm; 228 int err; 229 u8 dst; 230 231 if (!capable(CAP_SYS_ADMIN)) 232 return -EPERM; 233 234 ASSERT_RTNL(); 235 236 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_phonet_policy); 237 if (err < 0) 238 return err; 239 240 rtm = nlmsg_data(nlh); 241 if (rtm->rtm_table != RT_TABLE_MAIN || rtm->rtm_type != RTN_UNICAST) 242 return -EINVAL; 243 if (tb[RTA_DST] == NULL || tb[RTA_OIF] == NULL) 244 return -EINVAL; 245 dst = nla_get_u8(tb[RTA_DST]); 246 if (dst & 3) /* Phonet addresses only have 6 high-order bits */ 247 return -EINVAL; 248 249 dev = __dev_get_by_index(net, nla_get_u32(tb[RTA_OIF])); 250 if (dev == NULL) 251 return -ENODEV; 252 253 if (nlh->nlmsg_type == RTM_NEWROUTE) 254 err = phonet_route_add(dev, dst); 255 else 256 err = phonet_route_del(dev, dst); 257 if (!err) 258 rtm_phonet_notify(nlh->nlmsg_type, dev, dst); 259 return err; 260 } 261 262 static int route_dumpit(struct sk_buff *skb, struct netlink_callback *cb) 263 { 264 struct net *net = sock_net(skb->sk); 265 u8 addr, addr_idx = 0, addr_start_idx = cb->args[0]; 266 267 for (addr = 0; addr < 64; addr++) { 268 struct net_device *dev; 269 270 dev = phonet_route_get(net, addr << 2); 271 if (!dev) 272 continue; 273 274 if (addr_idx++ < addr_start_idx) 275 continue; 276 if (fill_route(skb, dev, addr << 2, NETLINK_CB(cb->skb).pid, 277 cb->nlh->nlmsg_seq, RTM_NEWROUTE)) 278 goto out; 279 } 280 281 out: 282 cb->args[0] = addr_idx; 283 cb->args[1] = 0; 284 285 return skb->len; 286 } 287 288 int __init phonet_netlink_register(void) 289 { 290 int err = __rtnl_register(PF_PHONET, RTM_NEWADDR, addr_doit, NULL); 291 if (err) 292 return err; 293 294 /* Further __rtnl_register() cannot fail */ 295 __rtnl_register(PF_PHONET, RTM_DELADDR, addr_doit, NULL); 296 __rtnl_register(PF_PHONET, RTM_GETADDR, NULL, getaddr_dumpit); 297 __rtnl_register(PF_PHONET, RTM_NEWROUTE, route_doit, NULL); 298 __rtnl_register(PF_PHONET, RTM_DELROUTE, route_doit, NULL); 299 __rtnl_register(PF_PHONET, RTM_GETROUTE, NULL, route_dumpit); 300 return 0; 301 } 302