1 /* 2 * Bridge netlink control interface 3 * 4 * Authors: 5 * Stephen Hemminger <shemminger@osdl.org> 6 * 7 * This program is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU General Public License 9 * as published by the Free Software Foundation; either version 10 * 2 of the License, or (at your option) any later version. 11 */ 12 13 #include <linux/kernel.h> 14 #include <linux/slab.h> 15 #include <linux/etherdevice.h> 16 #include <net/rtnetlink.h> 17 #include <net/net_namespace.h> 18 #include <net/sock.h> 19 20 #include "br_private.h" 21 #include "br_private_stp.h" 22 23 static inline size_t br_port_info_size(void) 24 { 25 return nla_total_size(1) /* IFLA_BRPORT_STATE */ 26 + nla_total_size(2) /* IFLA_BRPORT_PRIORITY */ 27 + nla_total_size(4) /* IFLA_BRPORT_COST */ 28 + nla_total_size(1) /* IFLA_BRPORT_MODE */ 29 + nla_total_size(1) /* IFLA_BRPORT_GUARD */ 30 + nla_total_size(1) /* IFLA_BRPORT_PROTECT */ 31 + 0; 32 } 33 34 static inline size_t br_nlmsg_size(void) 35 { 36 return NLMSG_ALIGN(sizeof(struct ifinfomsg)) 37 + nla_total_size(IFNAMSIZ) /* IFLA_IFNAME */ 38 + nla_total_size(MAX_ADDR_LEN) /* IFLA_ADDRESS */ 39 + nla_total_size(4) /* IFLA_MASTER */ 40 + nla_total_size(4) /* IFLA_MTU */ 41 + nla_total_size(4) /* IFLA_LINK */ 42 + nla_total_size(1) /* IFLA_OPERSTATE */ 43 + nla_total_size(br_port_info_size()); /* IFLA_PROTINFO */ 44 } 45 46 static int br_port_fill_attrs(struct sk_buff *skb, 47 const struct net_bridge_port *p) 48 { 49 u8 mode = !!(p->flags & BR_HAIRPIN_MODE); 50 51 if (nla_put_u8(skb, IFLA_BRPORT_STATE, p->state) || 52 nla_put_u16(skb, IFLA_BRPORT_PRIORITY, p->priority) || 53 nla_put_u32(skb, IFLA_BRPORT_COST, p->path_cost) || 54 nla_put_u8(skb, IFLA_BRPORT_MODE, mode) || 55 nla_put_u8(skb, IFLA_BRPORT_GUARD, !!(p->flags & BR_BPDU_GUARD)) || 56 nla_put_u8(skb, IFLA_BRPORT_PROTECT, !!(p->flags & BR_ROOT_BLOCK)) || 57 nla_put_u8(skb, IFLA_BRPORT_FAST_LEAVE, !!(p->flags & BR_MULTICAST_FAST_LEAVE))) 58 return -EMSGSIZE; 59 60 return 0; 61 } 62 63 /* 64 * Create one netlink message for one interface 65 * Contains port and master info as well as carrier and bridge state. 66 */ 67 static int br_fill_ifinfo(struct sk_buff *skb, const struct net_bridge_port *port, 68 u32 pid, u32 seq, int event, unsigned int flags) 69 { 70 const struct net_bridge *br = port->br; 71 const struct net_device *dev = port->dev; 72 struct ifinfomsg *hdr; 73 struct nlmsghdr *nlh; 74 u8 operstate = netif_running(dev) ? dev->operstate : IF_OPER_DOWN; 75 76 br_debug(br, "br_fill_info event %d port %s master %s\n", 77 event, dev->name, br->dev->name); 78 79 nlh = nlmsg_put(skb, pid, seq, event, sizeof(*hdr), flags); 80 if (nlh == NULL) 81 return -EMSGSIZE; 82 83 hdr = nlmsg_data(nlh); 84 hdr->ifi_family = AF_BRIDGE; 85 hdr->__ifi_pad = 0; 86 hdr->ifi_type = dev->type; 87 hdr->ifi_index = dev->ifindex; 88 hdr->ifi_flags = dev_get_flags(dev); 89 hdr->ifi_change = 0; 90 91 if (nla_put_string(skb, IFLA_IFNAME, dev->name) || 92 nla_put_u32(skb, IFLA_MASTER, br->dev->ifindex) || 93 nla_put_u32(skb, IFLA_MTU, dev->mtu) || 94 nla_put_u8(skb, IFLA_OPERSTATE, operstate) || 95 (dev->addr_len && 96 nla_put(skb, IFLA_ADDRESS, dev->addr_len, dev->dev_addr)) || 97 (dev->ifindex != dev->iflink && 98 nla_put_u32(skb, IFLA_LINK, dev->iflink))) 99 goto nla_put_failure; 100 101 if (event == RTM_NEWLINK) { 102 struct nlattr *nest 103 = nla_nest_start(skb, IFLA_PROTINFO | NLA_F_NESTED); 104 105 if (nest == NULL || br_port_fill_attrs(skb, port) < 0) 106 goto nla_put_failure; 107 nla_nest_end(skb, nest); 108 } 109 110 return nlmsg_end(skb, nlh); 111 112 nla_put_failure: 113 nlmsg_cancel(skb, nlh); 114 return -EMSGSIZE; 115 } 116 117 /* 118 * Notify listeners of a change in port information 119 */ 120 void br_ifinfo_notify(int event, struct net_bridge_port *port) 121 { 122 struct net *net = dev_net(port->dev); 123 struct sk_buff *skb; 124 int err = -ENOBUFS; 125 126 br_debug(port->br, "port %u(%s) event %d\n", 127 (unsigned int)port->port_no, port->dev->name, event); 128 129 skb = nlmsg_new(br_nlmsg_size(), GFP_ATOMIC); 130 if (skb == NULL) 131 goto errout; 132 133 err = br_fill_ifinfo(skb, port, 0, 0, event, 0); 134 if (err < 0) { 135 /* -EMSGSIZE implies BUG in br_nlmsg_size() */ 136 WARN_ON(err == -EMSGSIZE); 137 kfree_skb(skb); 138 goto errout; 139 } 140 rtnl_notify(skb, net, 0, RTNLGRP_LINK, NULL, GFP_ATOMIC); 141 return; 142 errout: 143 if (err < 0) 144 rtnl_set_sk_err(net, RTNLGRP_LINK, err); 145 } 146 147 /* 148 * Dump information about all ports, in response to GETLINK 149 */ 150 int br_getlink(struct sk_buff *skb, u32 pid, u32 seq, 151 struct net_device *dev) 152 { 153 int err = 0; 154 struct net_bridge_port *port = br_port_get_rcu(dev); 155 156 /* not a bridge port */ 157 if (!port) 158 goto out; 159 160 err = br_fill_ifinfo(skb, port, pid, seq, RTM_NEWLINK, NLM_F_MULTI); 161 out: 162 return err; 163 } 164 165 static const struct nla_policy ifla_brport_policy[IFLA_BRPORT_MAX + 1] = { 166 [IFLA_BRPORT_STATE] = { .type = NLA_U8 }, 167 [IFLA_BRPORT_COST] = { .type = NLA_U32 }, 168 [IFLA_BRPORT_PRIORITY] = { .type = NLA_U16 }, 169 [IFLA_BRPORT_MODE] = { .type = NLA_U8 }, 170 [IFLA_BRPORT_GUARD] = { .type = NLA_U8 }, 171 [IFLA_BRPORT_PROTECT] = { .type = NLA_U8 }, 172 }; 173 174 /* Change the state of the port and notify spanning tree */ 175 static int br_set_port_state(struct net_bridge_port *p, u8 state) 176 { 177 if (state > BR_STATE_BLOCKING) 178 return -EINVAL; 179 180 /* if kernel STP is running, don't allow changes */ 181 if (p->br->stp_enabled == BR_KERNEL_STP) 182 return -EBUSY; 183 184 if (!netif_running(p->dev) || 185 (!netif_carrier_ok(p->dev) && state != BR_STATE_DISABLED)) 186 return -ENETDOWN; 187 188 p->state = state; 189 br_log_state(p); 190 br_port_state_selection(p->br); 191 return 0; 192 } 193 194 /* Set/clear or port flags based on attribute */ 195 static void br_set_port_flag(struct net_bridge_port *p, struct nlattr *tb[], 196 int attrtype, unsigned long mask) 197 { 198 if (tb[attrtype]) { 199 u8 flag = nla_get_u8(tb[attrtype]); 200 if (flag) 201 p->flags |= mask; 202 else 203 p->flags &= ~mask; 204 } 205 } 206 207 /* Process bridge protocol info on port */ 208 static int br_setport(struct net_bridge_port *p, struct nlattr *tb[]) 209 { 210 int err; 211 212 br_set_port_flag(p, tb, IFLA_BRPORT_MODE, BR_HAIRPIN_MODE); 213 br_set_port_flag(p, tb, IFLA_BRPORT_GUARD, BR_BPDU_GUARD); 214 br_set_port_flag(p, tb, IFLA_BRPORT_FAST_LEAVE, BR_MULTICAST_FAST_LEAVE); 215 216 if (tb[IFLA_BRPORT_COST]) { 217 err = br_stp_set_path_cost(p, nla_get_u32(tb[IFLA_BRPORT_COST])); 218 if (err) 219 return err; 220 } 221 222 if (tb[IFLA_BRPORT_PRIORITY]) { 223 err = br_stp_set_port_priority(p, nla_get_u16(tb[IFLA_BRPORT_PRIORITY])); 224 if (err) 225 return err; 226 } 227 228 if (tb[IFLA_BRPORT_STATE]) { 229 err = br_set_port_state(p, nla_get_u8(tb[IFLA_BRPORT_STATE])); 230 if (err) 231 return err; 232 } 233 return 0; 234 } 235 236 /* Change state and parameters on port. */ 237 int br_setlink(struct net_device *dev, struct nlmsghdr *nlh) 238 { 239 struct ifinfomsg *ifm; 240 struct nlattr *protinfo; 241 struct net_bridge_port *p; 242 struct nlattr *tb[IFLA_BRPORT_MAX + 1]; 243 int err; 244 245 ifm = nlmsg_data(nlh); 246 247 protinfo = nlmsg_find_attr(nlh, sizeof(*ifm), IFLA_PROTINFO); 248 if (!protinfo) 249 return 0; 250 251 p = br_port_get_rtnl(dev); 252 if (!p) 253 return -EINVAL; 254 255 if (protinfo->nla_type & NLA_F_NESTED) { 256 err = nla_parse_nested(tb, IFLA_BRPORT_MAX, 257 protinfo, ifla_brport_policy); 258 if (err) 259 return err; 260 261 spin_lock_bh(&p->br->lock); 262 err = br_setport(p, tb); 263 spin_unlock_bh(&p->br->lock); 264 } else { 265 /* Binary compatability with old RSTP */ 266 if (nla_len(protinfo) < sizeof(u8)) 267 return -EINVAL; 268 269 spin_lock_bh(&p->br->lock); 270 err = br_set_port_state(p, nla_get_u8(protinfo)); 271 spin_unlock_bh(&p->br->lock); 272 } 273 274 if (err == 0) 275 br_ifinfo_notify(RTM_NEWLINK, p); 276 277 return err; 278 } 279 280 static int br_validate(struct nlattr *tb[], struct nlattr *data[]) 281 { 282 if (tb[IFLA_ADDRESS]) { 283 if (nla_len(tb[IFLA_ADDRESS]) != ETH_ALEN) 284 return -EINVAL; 285 if (!is_valid_ether_addr(nla_data(tb[IFLA_ADDRESS]))) 286 return -EADDRNOTAVAIL; 287 } 288 289 return 0; 290 } 291 292 struct rtnl_link_ops br_link_ops __read_mostly = { 293 .kind = "bridge", 294 .priv_size = sizeof(struct net_bridge), 295 .setup = br_dev_setup, 296 .validate = br_validate, 297 .dellink = br_dev_delete, 298 }; 299 300 int __init br_netlink_init(void) 301 { 302 return rtnl_link_register(&br_link_ops); 303 } 304 305 void __exit br_netlink_fini(void) 306 { 307 rtnl_link_unregister(&br_link_ops); 308 rtnl_unregister_all(PF_BRIDGE); 309 } 310