1 /* 2 * File: pn_netlink.c 3 * 4 * Phonet netlink interface 5 * 6 * Copyright (C) 2008 Nokia Corporation. 7 * 8 * Authors: Sakari Ailus <sakari.ailus@nokia.com> 9 * Remi Denis-Courmont 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 portid, 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) 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 (!netlink_capable(skb, CAP_NET_ADMIN)) 74 return -EPERM; 75 76 if (!netlink_capable(skb, CAP_SYS_ADMIN)) 77 return -EPERM; 78 79 ASSERT_RTNL(); 80 81 err = nlmsg_parse(nlh, sizeof(*ifm), tb, IFA_MAX, ifa_phonet_policy); 82 if (err < 0) 83 return err; 84 85 ifm = nlmsg_data(nlh); 86 if (tb[IFA_LOCAL] == NULL) 87 return -EINVAL; 88 pnaddr = nla_get_u8(tb[IFA_LOCAL]); 89 if (pnaddr & 3) 90 /* Phonet addresses only have 6 high-order bits */ 91 return -EINVAL; 92 93 dev = __dev_get_by_index(net, ifm->ifa_index); 94 if (dev == NULL) 95 return -ENODEV; 96 97 if (nlh->nlmsg_type == RTM_NEWADDR) 98 err = phonet_address_add(dev, pnaddr); 99 else 100 err = phonet_address_del(dev, pnaddr); 101 if (!err) 102 phonet_address_notify(nlh->nlmsg_type, dev, pnaddr); 103 return err; 104 } 105 106 static int fill_addr(struct sk_buff *skb, struct net_device *dev, u8 addr, 107 u32 portid, u32 seq, int event) 108 { 109 struct ifaddrmsg *ifm; 110 struct nlmsghdr *nlh; 111 112 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*ifm), 0); 113 if (nlh == NULL) 114 return -EMSGSIZE; 115 116 ifm = nlmsg_data(nlh); 117 ifm->ifa_family = AF_PHONET; 118 ifm->ifa_prefixlen = 0; 119 ifm->ifa_flags = IFA_F_PERMANENT; 120 ifm->ifa_scope = RT_SCOPE_LINK; 121 ifm->ifa_index = dev->ifindex; 122 if (nla_put_u8(skb, IFA_LOCAL, addr)) 123 goto nla_put_failure; 124 nlmsg_end(skb, nlh); 125 return 0; 126 127 nla_put_failure: 128 nlmsg_cancel(skb, nlh); 129 return -EMSGSIZE; 130 } 131 132 static int getaddr_dumpit(struct sk_buff *skb, struct netlink_callback *cb) 133 { 134 struct phonet_device_list *pndevs; 135 struct phonet_device *pnd; 136 int dev_idx = 0, dev_start_idx = cb->args[0]; 137 int addr_idx = 0, addr_start_idx = cb->args[1]; 138 139 pndevs = phonet_device_list(sock_net(skb->sk)); 140 rcu_read_lock(); 141 list_for_each_entry_rcu(pnd, &pndevs->list, list) { 142 u8 addr; 143 144 if (dev_idx > dev_start_idx) 145 addr_start_idx = 0; 146 if (dev_idx++ < dev_start_idx) 147 continue; 148 149 addr_idx = 0; 150 for_each_set_bit(addr, pnd->addrs, 64) { 151 if (addr_idx++ < addr_start_idx) 152 continue; 153 154 if (fill_addr(skb, pnd->netdev, addr << 2, 155 NETLINK_CB(cb->skb).portid, 156 cb->nlh->nlmsg_seq, RTM_NEWADDR) < 0) 157 goto out; 158 } 159 } 160 161 out: 162 rcu_read_unlock(); 163 cb->args[0] = dev_idx; 164 cb->args[1] = addr_idx; 165 166 return skb->len; 167 } 168 169 /* Routes handling */ 170 171 static int fill_route(struct sk_buff *skb, struct net_device *dev, u8 dst, 172 u32 portid, u32 seq, int event) 173 { 174 struct rtmsg *rtm; 175 struct nlmsghdr *nlh; 176 177 nlh = nlmsg_put(skb, portid, seq, event, sizeof(*rtm), 0); 178 if (nlh == NULL) 179 return -EMSGSIZE; 180 181 rtm = nlmsg_data(nlh); 182 rtm->rtm_family = AF_PHONET; 183 rtm->rtm_dst_len = 6; 184 rtm->rtm_src_len = 0; 185 rtm->rtm_tos = 0; 186 rtm->rtm_table = RT_TABLE_MAIN; 187 rtm->rtm_protocol = RTPROT_STATIC; 188 rtm->rtm_scope = RT_SCOPE_UNIVERSE; 189 rtm->rtm_type = RTN_UNICAST; 190 rtm->rtm_flags = 0; 191 if (nla_put_u8(skb, RTA_DST, dst) || 192 nla_put_u32(skb, RTA_OIF, dev->ifindex)) 193 goto nla_put_failure; 194 nlmsg_end(skb, nlh); 195 return 0; 196 197 nla_put_failure: 198 nlmsg_cancel(skb, nlh); 199 return -EMSGSIZE; 200 } 201 202 void rtm_phonet_notify(int event, struct net_device *dev, u8 dst) 203 { 204 struct sk_buff *skb; 205 int err = -ENOBUFS; 206 207 skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + 208 nla_total_size(1) + nla_total_size(4), GFP_KERNEL); 209 if (skb == NULL) 210 goto errout; 211 err = fill_route(skb, dev, dst, 0, 0, event); 212 if (err < 0) { 213 WARN_ON(err == -EMSGSIZE); 214 kfree_skb(skb); 215 goto errout; 216 } 217 rtnl_notify(skb, dev_net(dev), 0, 218 RTNLGRP_PHONET_ROUTE, NULL, GFP_KERNEL); 219 return; 220 errout: 221 rtnl_set_sk_err(dev_net(dev), RTNLGRP_PHONET_ROUTE, err); 222 } 223 224 static const struct nla_policy rtm_phonet_policy[RTA_MAX+1] = { 225 [RTA_DST] = { .type = NLA_U8 }, 226 [RTA_OIF] = { .type = NLA_U32 }, 227 }; 228 229 static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh) 230 { 231 struct net *net = sock_net(skb->sk); 232 struct nlattr *tb[RTA_MAX+1]; 233 struct net_device *dev; 234 struct rtmsg *rtm; 235 int err; 236 u8 dst; 237 238 if (!netlink_capable(skb, CAP_NET_ADMIN)) 239 return -EPERM; 240 241 if (!netlink_capable(skb, CAP_SYS_ADMIN)) 242 return -EPERM; 243 244 ASSERT_RTNL(); 245 246 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_phonet_policy); 247 if (err < 0) 248 return err; 249 250 rtm = nlmsg_data(nlh); 251 if (rtm->rtm_table != RT_TABLE_MAIN || rtm->rtm_type != RTN_UNICAST) 252 return -EINVAL; 253 if (tb[RTA_DST] == NULL || tb[RTA_OIF] == NULL) 254 return -EINVAL; 255 dst = nla_get_u8(tb[RTA_DST]); 256 if (dst & 3) /* Phonet addresses only have 6 high-order bits */ 257 return -EINVAL; 258 259 dev = __dev_get_by_index(net, nla_get_u32(tb[RTA_OIF])); 260 if (dev == NULL) 261 return -ENODEV; 262 263 if (nlh->nlmsg_type == RTM_NEWROUTE) 264 err = phonet_route_add(dev, dst); 265 else 266 err = phonet_route_del(dev, dst); 267 if (!err) 268 rtm_phonet_notify(nlh->nlmsg_type, dev, dst); 269 return err; 270 } 271 272 static int route_dumpit(struct sk_buff *skb, struct netlink_callback *cb) 273 { 274 struct net *net = sock_net(skb->sk); 275 u8 addr; 276 277 rcu_read_lock(); 278 for (addr = cb->args[0]; addr < 64; addr++) { 279 struct net_device *dev = phonet_route_get_rcu(net, addr << 2); 280 281 if (!dev) 282 continue; 283 284 if (fill_route(skb, dev, addr << 2, NETLINK_CB(cb->skb).portid, 285 cb->nlh->nlmsg_seq, RTM_NEWROUTE) < 0) 286 goto out; 287 } 288 289 out: 290 rcu_read_unlock(); 291 cb->args[0] = addr; 292 293 return skb->len; 294 } 295 296 int __init phonet_netlink_register(void) 297 { 298 int err = __rtnl_register(PF_PHONET, RTM_NEWADDR, addr_doit, 299 NULL, NULL); 300 if (err) 301 return err; 302 303 /* Further __rtnl_register() cannot fail */ 304 __rtnl_register(PF_PHONET, RTM_DELADDR, addr_doit, NULL, NULL); 305 __rtnl_register(PF_PHONET, RTM_GETADDR, NULL, getaddr_dumpit, NULL); 306 __rtnl_register(PF_PHONET, RTM_NEWROUTE, route_doit, NULL, NULL); 307 __rtnl_register(PF_PHONET, RTM_DELROUTE, route_doit, NULL, NULL); 308 __rtnl_register(PF_PHONET, RTM_GETROUTE, NULL, route_dumpit, NULL); 309 return 0; 310 } 311