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 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 if (nla_put_u8(skb, IFA_LOCAL, addr)) 120 goto nla_put_failure; 121 return nlmsg_end(skb, nlh); 122 123 nla_put_failure: 124 nlmsg_cancel(skb, nlh); 125 return -EMSGSIZE; 126 } 127 128 static int getaddr_dumpit(struct sk_buff *skb, struct netlink_callback *cb) 129 { 130 struct phonet_device_list *pndevs; 131 struct phonet_device *pnd; 132 int dev_idx = 0, dev_start_idx = cb->args[0]; 133 int addr_idx = 0, addr_start_idx = cb->args[1]; 134 135 pndevs = phonet_device_list(sock_net(skb->sk)); 136 rcu_read_lock(); 137 list_for_each_entry_rcu(pnd, &pndevs->list, list) { 138 u8 addr; 139 140 if (dev_idx > dev_start_idx) 141 addr_start_idx = 0; 142 if (dev_idx++ < dev_start_idx) 143 continue; 144 145 addr_idx = 0; 146 for_each_set_bit(addr, pnd->addrs, 64) { 147 if (addr_idx++ < addr_start_idx) 148 continue; 149 150 if (fill_addr(skb, pnd->netdev, addr << 2, 151 NETLINK_CB(cb->skb).pid, 152 cb->nlh->nlmsg_seq, RTM_NEWADDR) < 0) 153 goto out; 154 } 155 } 156 157 out: 158 rcu_read_unlock(); 159 cb->args[0] = dev_idx; 160 cb->args[1] = addr_idx; 161 162 return skb->len; 163 } 164 165 /* Routes handling */ 166 167 static int fill_route(struct sk_buff *skb, struct net_device *dev, u8 dst, 168 u32 pid, u32 seq, int event) 169 { 170 struct rtmsg *rtm; 171 struct nlmsghdr *nlh; 172 173 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*rtm), 0); 174 if (nlh == NULL) 175 return -EMSGSIZE; 176 177 rtm = nlmsg_data(nlh); 178 rtm->rtm_family = AF_PHONET; 179 rtm->rtm_dst_len = 6; 180 rtm->rtm_src_len = 0; 181 rtm->rtm_tos = 0; 182 rtm->rtm_table = RT_TABLE_MAIN; 183 rtm->rtm_protocol = RTPROT_STATIC; 184 rtm->rtm_scope = RT_SCOPE_UNIVERSE; 185 rtm->rtm_type = RTN_UNICAST; 186 rtm->rtm_flags = 0; 187 if (nla_put_u8(skb, RTA_DST, dst) || 188 nla_put_u32(skb, RTA_OIF, dev->ifindex)) 189 goto nla_put_failure; 190 return nlmsg_end(skb, nlh); 191 192 nla_put_failure: 193 nlmsg_cancel(skb, nlh); 194 return -EMSGSIZE; 195 } 196 197 void rtm_phonet_notify(int event, struct net_device *dev, u8 dst) 198 { 199 struct sk_buff *skb; 200 int err = -ENOBUFS; 201 202 skb = nlmsg_new(NLMSG_ALIGN(sizeof(struct ifaddrmsg)) + 203 nla_total_size(1) + nla_total_size(4), GFP_KERNEL); 204 if (skb == NULL) 205 goto errout; 206 err = fill_route(skb, dev, dst, 0, 0, event); 207 if (err < 0) { 208 WARN_ON(err == -EMSGSIZE); 209 kfree_skb(skb); 210 goto errout; 211 } 212 rtnl_notify(skb, dev_net(dev), 0, 213 RTNLGRP_PHONET_ROUTE, NULL, GFP_KERNEL); 214 return; 215 errout: 216 rtnl_set_sk_err(dev_net(dev), RTNLGRP_PHONET_ROUTE, err); 217 } 218 219 static const struct nla_policy rtm_phonet_policy[RTA_MAX+1] = { 220 [RTA_DST] = { .type = NLA_U8 }, 221 [RTA_OIF] = { .type = NLA_U32 }, 222 }; 223 224 static int route_doit(struct sk_buff *skb, struct nlmsghdr *nlh, void *attr) 225 { 226 struct net *net = sock_net(skb->sk); 227 struct nlattr *tb[RTA_MAX+1]; 228 struct net_device *dev; 229 struct rtmsg *rtm; 230 int err; 231 u8 dst; 232 233 if (!capable(CAP_SYS_ADMIN)) 234 return -EPERM; 235 236 ASSERT_RTNL(); 237 238 err = nlmsg_parse(nlh, sizeof(*rtm), tb, RTA_MAX, rtm_phonet_policy); 239 if (err < 0) 240 return err; 241 242 rtm = nlmsg_data(nlh); 243 if (rtm->rtm_table != RT_TABLE_MAIN || rtm->rtm_type != RTN_UNICAST) 244 return -EINVAL; 245 if (tb[RTA_DST] == NULL || tb[RTA_OIF] == NULL) 246 return -EINVAL; 247 dst = nla_get_u8(tb[RTA_DST]); 248 if (dst & 3) /* Phonet addresses only have 6 high-order bits */ 249 return -EINVAL; 250 251 dev = __dev_get_by_index(net, nla_get_u32(tb[RTA_OIF])); 252 if (dev == NULL) 253 return -ENODEV; 254 255 if (nlh->nlmsg_type == RTM_NEWROUTE) 256 err = phonet_route_add(dev, dst); 257 else 258 err = phonet_route_del(dev, dst); 259 if (!err) 260 rtm_phonet_notify(nlh->nlmsg_type, dev, dst); 261 return err; 262 } 263 264 static int route_dumpit(struct sk_buff *skb, struct netlink_callback *cb) 265 { 266 struct net *net = sock_net(skb->sk); 267 u8 addr, addr_idx = 0, addr_start_idx = cb->args[0]; 268 269 rcu_read_lock(); 270 for (addr = 0; addr < 64; addr++) { 271 struct net_device *dev; 272 273 dev = phonet_route_get_rcu(net, addr << 2); 274 if (!dev) 275 continue; 276 277 if (addr_idx++ < addr_start_idx) 278 continue; 279 if (fill_route(skb, dev, addr << 2, NETLINK_CB(cb->skb).pid, 280 cb->nlh->nlmsg_seq, RTM_NEWROUTE)) 281 goto out; 282 } 283 284 out: 285 rcu_read_unlock(); 286 cb->args[0] = addr_idx; 287 cb->args[1] = 0; 288 289 return skb->len; 290 } 291 292 int __init phonet_netlink_register(void) 293 { 294 int err = __rtnl_register(PF_PHONET, RTM_NEWADDR, addr_doit, 295 NULL, NULL); 296 if (err) 297 return err; 298 299 /* Further __rtnl_register() cannot fail */ 300 __rtnl_register(PF_PHONET, RTM_DELADDR, addr_doit, NULL, NULL); 301 __rtnl_register(PF_PHONET, RTM_GETADDR, NULL, getaddr_dumpit, NULL); 302 __rtnl_register(PF_PHONET, RTM_NEWROUTE, route_doit, NULL, NULL); 303 __rtnl_register(PF_PHONET, RTM_DELROUTE, route_doit, NULL, NULL); 304 __rtnl_register(PF_PHONET, RTM_GETROUTE, NULL, route_dumpit, NULL); 305 return 0; 306 } 307