src/netlink.c

   1 /**
   2  * Copyright (C) 2017 Hans Dedecker <dedeckeh@gmail.com>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License v2 as published by
   6  * the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #include <errno.h>
  16 #include <string.h>
  17 #include <syslog.h>
  18
  19 #include <linux/netlink.h>
  20 #include <linux/if_addr.h>
  21 #include <linux/neighbour.h>
  22 #include <linux/rtnetlink.h>
  23
  24 #include <netlink/msg.h>
  25 #include <netlink/socket.h>
  26 #include <netlink/attr.h>
  27
  28 #include <arpa/inet.h>
  29 #include <libubox/list.h>
  30
  31 #include "odhcpd.h"
  32
  33 struct event_socket {
  34         struct odhcpd_event ev;
  35         struct nl_sock *sock;
  36         int sock_bufsize;
  37 };
  38
  39 static void handle_rtnl_event(struct odhcpd_event *ev);
  40 static int cb_rtnl_valid(struct nl_msg *msg, void *arg);
  41 static void catch_rtnl_err(struct odhcpd_event *e, int error);
  42 static struct nl_sock *create_socket(int protocol);
  43
  44 static struct nl_sock *rtnl_socket = NULL;
  45 struct list_head netevent_handler_list = LIST_HEAD_INIT(netevent_handler_list);
  46 static struct event_socket rtnl_event = {
  47         .ev = {
  48                 .uloop = {.fd = - 1, },
  49                 .handle_dgram = NULL,
  50                 .handle_error = catch_rtnl_err,
  51                 .recv_msgs = handle_rtnl_event,
  52         },
  53         .sock = NULL,
  54         .sock_bufsize = 133120,
  55 };
  56
  57 int netlink_init(void)
  58 {
  59         rtnl_socket = create_socket(NETLINK_ROUTE);
  60         if (!rtnl_socket) {
  61                 syslog(LOG_ERR, "Unable to open nl socket: %m");
  62                 goto err;
  63         }
  64
  65         rtnl_event.sock = create_socket(NETLINK_ROUTE);
  66         if (!rtnl_event.sock) {
  67                 syslog(LOG_ERR, "Unable to open nl event socket: %m");
  68                 goto err;
  69         }
  70
  71         rtnl_event.ev.uloop.fd = nl_socket_get_fd(rtnl_event.sock);
  72
  73         if (nl_socket_set_buffer_size(rtnl_event.sock, rtnl_event.sock_bufsize, 0))
  74                 goto err;
  75
  76         nl_socket_disable_seq_check(rtnl_event.sock);
  77
  78         nl_socket_modify_cb(rtnl_event.sock, NL_CB_VALID, NL_CB_CUSTOM,
  79                         cb_rtnl_valid, NULL);
  80
  81         // Receive IPv4 address, IPv6 address, IPv6 routes and neighbor events
  82         if (nl_socket_add_memberships(rtnl_event.sock, RTNLGRP_IPV4_IFADDR,
  83                                 RTNLGRP_IPV6_IFADDR, RTNLGRP_IPV6_ROUTE,
  84                                 RTNLGRP_NEIGH, RTNLGRP_LINK, 0))
  85                 goto err;
  86
  87         odhcpd_register(&rtnl_event.ev);
  88
  89         return 0;
  90
  91 err:
  92         if (rtnl_socket) {
  93                 nl_socket_free(rtnl_socket);
  94                 rtnl_socket = NULL;
  95         }
  96
  97         if (rtnl_event.sock) {
  98                 nl_socket_free(rtnl_event.sock);
  99                 rtnl_event.sock = NULL;
 100                 rtnl_event.ev.uloop.fd = -1;
 101         }
 102
 103         return -1;
 104 }
 105
 106
 107 int netlink_add_netevent_handler(struct netevent_handler *handler)
 108 {
 109         if (!handler->cb)
 110                 return -1;
 111
 112         list_add(&handler->head, &netevent_handler_list);
 113
 114         return 0;
 115 }
 116
 117 static void call_netevent_handler_list(unsigned long event, struct netevent_handler_info *info)
 118 {
 119         struct netevent_handler *handler;
 120
 121         list_for_each_entry(handler, &netevent_handler_list, head)
 122                 handler->cb(event, info);
 123 }
 124
 125 static void handle_rtnl_event(struct odhcpd_event *e)
 126 {
 127         struct event_socket *ev_sock = container_of(e, struct event_socket, ev);
 128
 129         nl_recvmsgs_default(ev_sock->sock);
 130 }
 131
 132 static void refresh_iface_addr4(struct netevent_handler_info *event_info)
 133 {
 134         struct odhcpd_ipaddr *addr = NULL;
 135         struct interface *iface = event_info->iface;
 136         ssize_t len = netlink_get_interface_addrs(iface->ifindex, false, &addr);
 137
 138         if (len < 0)
 139                 return;
 140
 141         bool change = len != (ssize_t)iface->addr4_len;
 142         for (ssize_t i = 0; !change && i < len; ++i)
 143                 if (addr[i].addr.in.s_addr != iface->addr4[i].addr.in.s_addr)
 144                         change = true;
 145
 146         event_info->addrs_old.addrs = iface->addr4;
 147         event_info->addrs_old.len = iface->addr4_len;
 148
 149         iface->addr4 = addr;
 150         iface->addr4_len = len;
 151
 152         if (change)
 153                 call_netevent_handler_list(NETEV_ADDRLIST_CHANGE, event_info);
 154
 155         free(event_info->addrs_old.addrs);
 156 }
 157
 158 static void refresh_iface_addr6(struct netevent_handler_info *event_info)
 159 {
 160         struct odhcpd_ipaddr *addr = NULL;
 161         struct interface *iface = event_info->iface;
 162         ssize_t len = netlink_get_interface_addrs(iface->ifindex, true, &addr);
 163
 164         if (len < 0)
 165                 return;
 166
 167         bool change = len != (ssize_t)iface->addr6_len;
 168         for (ssize_t i = 0; !change && i < len; ++i)
 169                 if (!IN6_ARE_ADDR_EQUAL(&addr[i].addr.in6, &iface->addr6[i].addr.in6) ||
 170                                 (addr[i].preferred > 0) != (iface->addr6[i].preferred > 0) ||
 171                                 addr[i].valid < iface->addr6[i].valid ||
 172                                 addr[i].preferred < iface->addr6[i].preferred)
 173                         change = true;
 174
 175         event_info->addrs_old.addrs = iface->addr6;
 176         event_info->addrs_old.len = iface->addr6_len;
 177
 178         iface->addr6 = addr;
 179         iface->addr6_len = len;
 180
 181         if (change)
 182                 call_netevent_handler_list(NETEV_ADDR6LIST_CHANGE, event_info);
 183
 184         free(event_info->addrs_old.addrs);
 185 }
 186
 187 // Handler for neighbor cache entries from the kernel. This is our source
 188 // to learn and unlearn hosts on interfaces.
 189 static int cb_rtnl_valid(struct nl_msg *msg, _unused void *arg)
 190 {
 191         struct nlmsghdr *hdr = nlmsg_hdr(msg);
 192         struct netevent_handler_info event_info;
 193         bool add = false;
 194         char ipbuf[INET6_ADDRSTRLEN];
 195
 196         memset(&event_info, 0, sizeof(event_info));
 197         switch (hdr->nlmsg_type) {
 198         case RTM_NEWLINK: {
 199                 struct ifinfomsg *ifi = nlmsg_data(hdr);
 200                 struct nlattr *nla[__IFLA_MAX];
 201
 202                 if (!nlmsg_valid_hdr(hdr, sizeof(*ifi)) ||
 203                                 ifi->ifi_family != AF_UNSPEC)
 204                         return NL_SKIP;
 205
 206                 nlmsg_parse(hdr, sizeof(*ifi), nla, __IFLA_MAX - 1, NULL);
 207                 if (!nla[IFLA_IFNAME])
 208                         return NL_SKIP;
 209
 210                 event_info.iface = odhcpd_get_interface_by_name(nla_get_string(nla[IFLA_IFNAME]));
 211                 if (!event_info.iface)
 212                         return NL_SKIP;
 213
 214                 if (event_info.iface->ifindex != ifi->ifi_index) {
 215                         event_info.iface->ifindex = ifi->ifi_index;
 216                         call_netevent_handler_list(NETEV_IFINDEX_CHANGE, &event_info);
 217                 }
 218                 break;
 219         }
 220
 221         case RTM_NEWROUTE:
 222                 add = true;
 223                 /* fall through */
 224         case RTM_DELROUTE: {
 225                 struct rtmsg *rtm = nlmsg_data(hdr);
 226                 struct nlattr *nla[__RTA_MAX];
 227
 228                 if (!nlmsg_valid_hdr(hdr, sizeof(*rtm)) ||
 229                                 rtm->rtm_family != AF_INET6)
 230                         return NL_SKIP;
 231
 232                 nlmsg_parse(hdr, sizeof(*rtm), nla, __RTA_MAX - 1, NULL);
 233
 234                 event_info.rt.dst_len = rtm->rtm_dst_len;
 235                 if (nla[RTA_DST])
 236                         nla_memcpy(&event_info.rt.dst, nla[RTA_DST],
 237                                         sizeof(&event_info.rt.dst));
 238
 239                 if (nla[RTA_OIF])
 240                         event_info.iface = odhcpd_get_interface_by_index(nla_get_u32(nla[RTA_OIF]));
 241
 242                 if (nla[RTA_GATEWAY])
 243                         nla_memcpy(&event_info.rt.gateway, nla[RTA_GATEWAY],
 244                                         sizeof(&event_info.rt.gateway));
 245
 246                 call_netevent_handler_list(add ? NETEV_ROUTE6_ADD : NETEV_ROUTE6_DEL,
 247                                         &event_info);
 248                 break;
 249         }
 250
 251         case RTM_NEWADDR:
 252                 add = true;
 253                 /* fall through */
 254         case RTM_DELADDR: {
 255                 struct ifaddrmsg *ifa = nlmsg_data(hdr);
 256                 struct nlattr *nla[__IFA_MAX];
 257
 258                 if (!nlmsg_valid_hdr(hdr, sizeof(*ifa)) ||
 259                                 (ifa->ifa_family != AF_INET6 &&
 260                                  ifa->ifa_family != AF_INET))
 261                         return NL_SKIP;
 262
 263                 event_info.iface = odhcpd_get_interface_by_index(ifa->ifa_index);
 264                 if (!event_info.iface)
 265                         return NL_SKIP;
 266
 267                 nlmsg_parse(hdr, sizeof(*ifa), nla, __IFA_MAX - 1, NULL);
 268
 269                 if (ifa->ifa_family == AF_INET6) {
 270                         if (!nla[IFA_ADDRESS])
 271                                 return NL_SKIP;
 272
 273                         nla_memcpy(&event_info.addr, nla[IFA_ADDRESS], sizeof(event_info.addr));
 274
 275                         if (IN6_IS_ADDR_LINKLOCAL(&event_info.addr) ||
 276                             IN6_IS_ADDR_MULTICAST(&event_info.addr))
 277                                 return NL_SKIP;
 278
 279                         inet_ntop(AF_INET6, &event_info.addr, ipbuf, sizeof(ipbuf));
 280                         syslog(LOG_DEBUG, "Netlink %s %s%%%s", add ? "newaddr" : "deladdr",
 281                                 ipbuf, event_info.iface->ifname);
 282
 283                         call_netevent_handler_list(add ? NETEV_ADDR6_ADD : NETEV_ADDR6_DEL,
 284                                                         &event_info);
 285
 286                         refresh_iface_addr6(&event_info);
 287                 } else {
 288                         if (!nla[IFA_LOCAL])
 289                                 return NL_SKIP;
 290
 291                         nla_memcpy(&event_info.addr, nla[IFA_LOCAL], sizeof(event_info.addr));
 292
 293                         inet_ntop(AF_INET, &event_info.addr, ipbuf, sizeof(ipbuf));
 294                         syslog(LOG_DEBUG, "Netlink %s %s%%%s", add ? "newaddr" : "deladdr",
 295                                 ipbuf, event_info.iface->ifname);
 296
 297                         call_netevent_handler_list(add ? NETEV_ADDR_ADD : NETEV_ADDR_DEL,
 298                                                         &event_info);
 299
 300                         refresh_iface_addr4(&event_info);
 301                 }
 302                 break;
 303         }
 304
 305         case RTM_NEWNEIGH:
 306                 add = true;
 307                 /* fall through */
 308         case RTM_DELNEIGH: {
 309                 struct ndmsg *ndm = nlmsg_data(hdr);
 310                 struct nlattr *nla[__NDA_MAX];
 311
 312                 if (!nlmsg_valid_hdr(hdr, sizeof(*ndm)) ||
 313                                 ndm->ndm_family != AF_INET6)
 314                         return NL_SKIP;
 315
 316                 event_info.iface = odhcpd_get_interface_by_index(ndm->ndm_ifindex);
 317                 if (!event_info.iface)
 318                         return NL_SKIP;
 319
 320                 nlmsg_parse(hdr, sizeof(*ndm), nla, __NDA_MAX - 1, NULL);
 321                 if (!nla[NDA_DST])
 322                         return NL_SKIP;
 323
 324                 nla_memcpy(&event_info.neigh.dst, nla[NDA_DST], sizeof(event_info.neigh.dst));
 325
 326                 if (IN6_IS_ADDR_LINKLOCAL(&event_info.neigh.dst) ||
 327                     IN6_IS_ADDR_MULTICAST(&event_info.neigh.dst))
 328                         return NL_SKIP;
 329
 330                 inet_ntop(AF_INET6, &event_info.neigh.dst, ipbuf, sizeof(ipbuf));
 331                 syslog(LOG_DEBUG, "Netlink %s %s%%%s", true ? "newneigh" : "delneigh",
 332                         ipbuf, event_info.iface->ifname);
 333
 334                 event_info.neigh.state = ndm->ndm_state;
 335                 event_info.neigh.flags = ndm->ndm_flags;
 336
 337                 call_netevent_handler_list(add ? NETEV_NEIGH6_ADD : NETEV_NEIGH6_DEL,
 338                                                 &event_info);
 339                 break;
 340         }
 341
 342         default:
 343                 return NL_SKIP;
 344         }
 345
 346         return NL_OK;
 347 }
 348
 349 static void catch_rtnl_err(struct odhcpd_event *e, int error)
 350 {
 351         struct event_socket *ev_sock = container_of(e, struct event_socket, ev);
 352
 353         if (error != ENOBUFS)
 354                 goto err;
 355
 356         /* Double netlink event buffer size */
 357         ev_sock->sock_bufsize *= 2;
 358
 359         if (nl_socket_set_buffer_size(ev_sock->sock, ev_sock->sock_bufsize, 0))
 360                 goto err;
 361
 362         netlink_dump_addr_table(true);
 363         return;
 364
 365 err:
 366         odhcpd_deregister(e);
 367 }
 368
 369 static struct nl_sock *create_socket(int protocol)
 370 {
 371         struct nl_sock *nl_sock;
 372
 373         nl_sock = nl_socket_alloc();
 374         if (!nl_sock)
 375                 goto err;
 376
 377         if (nl_connect(nl_sock, protocol) < 0)
 378                 goto err;
 379
 380         return nl_sock;
 381
 382 err:
 383         if (nl_sock)
 384                 nl_socket_free(nl_sock);
 385
 386         return NULL;
 387 }
 388
 389
 390 struct addr_info {
 391         int ifindex;
 392         int af;
 393         struct odhcpd_ipaddr **addrs;
 394         int pending;
 395         ssize_t ret;
 396 };
 397
 398
 399 static int cb_valid_handler(struct nl_msg *msg, void *arg)
 400 {
 401         struct addr_info *ctxt = (struct addr_info *)arg;
 402         struct odhcpd_ipaddr *addrs = *(ctxt->addrs);
 403         struct nlmsghdr *hdr = nlmsg_hdr(msg);
 404         struct ifaddrmsg *ifa;
 405         struct nlattr *nla[__IFA_MAX], *nla_addr = NULL;
 406
 407         if (hdr->nlmsg_type != RTM_NEWADDR)
 408                 return NL_SKIP;
 409
 410         ifa = NLMSG_DATA(hdr);
 411         if (ifa->ifa_scope != RT_SCOPE_UNIVERSE ||
 412                         (ctxt->af != ifa->ifa_family) ||
 413                         (ctxt->ifindex && ifa->ifa_index != (unsigned)ctxt->ifindex))
 414                 return NL_SKIP;
 415
 416         nlmsg_parse(hdr, sizeof(*ifa), nla, __IFA_MAX - 1, NULL);
 417
 418         switch (ifa->ifa_family) {
 419         case AF_INET6:
 420                 if (nla[IFA_ADDRESS])
 421                         nla_addr = nla[IFA_ADDRESS];
 422                 break;
 423
 424         case AF_INET:
 425                 if (nla[IFA_LOCAL])
 426                         nla_addr = nla[IFA_LOCAL];
 427                 break;
 428
 429         default:
 430                 break;
 431         }
 432         if (!nla_addr)
 433                 return NL_SKIP;
 434
 435         addrs = realloc(addrs, sizeof(*addrs)*(ctxt->ret + 1));
 436         if (!addrs)
 437                 return NL_SKIP;
 438
 439         memset(&addrs[ctxt->ret], 0, sizeof(addrs[ctxt->ret]));
 440         addrs[ctxt->ret].prefix = ifa->ifa_prefixlen;
 441
 442         nla_memcpy(&addrs[ctxt->ret].addr, nla_addr,
 443                         sizeof(addrs[ctxt->ret].addr));
 444
 445         if (nla[IFA_BROADCAST])
 446                 nla_memcpy(&addrs[ctxt->ret].broadcast, nla[IFA_BROADCAST],
 447                                 sizeof(addrs[ctxt->ret].broadcast));
 448
 449         if (nla[IFA_CACHEINFO]) {
 450                 struct ifa_cacheinfo *ifc = nla_data(nla[IFA_CACHEINFO]);
 451
 452                 addrs[ctxt->ret].preferred = ifc->ifa_prefered;
 453                 addrs[ctxt->ret].valid = ifc->ifa_valid;
 454         }
 455
 456         if (ifa->ifa_flags & IFA_F_DEPRECATED)
 457                 addrs[ctxt->ret].preferred = 0;
 458
 459         ctxt->ret++;
 460         *(ctxt->addrs) = addrs;
 461
 462         return NL_OK;
 463 }
 464
 465
 466 static int cb_finish_handler(_unused struct nl_msg *msg, void *arg)
 467 {
 468         struct addr_info *ctxt = (struct addr_info *)arg;
 469
 470         ctxt->pending = 0;
 471
 472         return NL_STOP;
 473 }
 474
 475
 476 static int cb_error_handler(_unused struct sockaddr_nl *nla, struct nlmsgerr *err,
 477                 void *arg)
 478 {
 479         struct addr_info *ctxt = (struct addr_info *)arg;
 480
 481         ctxt->pending = 0;
 482         ctxt->ret = err->error;
 483
 484         return NL_STOP;
 485 }
 486
 487
 488 static int prefix_cmp(const void *va, const void *vb)
 489 {
 490         const struct odhcpd_ipaddr *a = va, *b = vb;
 491         int ret = 0;
 492
 493         if (a->prefix == b->prefix) {
 494                 ret = (ntohl(a->addr.in.s_addr) < ntohl(b->addr.in.s_addr)) ? 1 :
 495                         (ntohl(a->addr.in.s_addr) > ntohl(b->addr.in.s_addr)) ? -1 : 0;
 496         } else
 497                 ret = a->prefix < b->prefix ? 1 : -1;
 498
 499         return ret;
 500 }
 501
 502
 503 // compare IPv6 prefixes
 504 static int prefix6_cmp(const void *va, const void *vb)
 505 {
 506         const struct odhcpd_ipaddr *a = va, *b = vb;
 507         uint32_t a_pref = IN6_IS_ADDR_ULA(&a->addr.in6) ? 1 : a->preferred;
 508         uint32_t b_pref = IN6_IS_ADDR_ULA(&b->addr.in6) ? 1 : b->preferred;
 509         return (a_pref < b_pref) ? 1 : (a_pref > b_pref) ? -1 : 0;
 510 }
 511
 512
 513 // Detect an IPV6-address currently assigned to the given interface
 514 ssize_t netlink_get_interface_addrs(int ifindex, bool v6, struct odhcpd_ipaddr **addrs)
 515 {
 516         struct nl_msg *msg;
 517         struct ifaddrmsg ifa = {
 518                 .ifa_family = v6? AF_INET6: AF_INET,
 519                 .ifa_prefixlen = 0,
 520                 .ifa_flags = 0,
 521                 .ifa_scope = 0,
 522                 .ifa_index = ifindex, };
 523         struct nl_cb *cb = nl_cb_alloc(NL_CB_DEFAULT);
 524         struct addr_info ctxt = {
 525                 .ifindex = ifindex,
 526                 .af = v6? AF_INET6: AF_INET,
 527                 .addrs = addrs,
 528                 .ret = 0,
 529                 .pending = 1,
 530         };
 531
 532         if (!cb) {
 533                 ctxt.ret = -1;
 534                 goto out;
 535         }
 536
 537         msg = nlmsg_alloc_simple(RTM_GETADDR, NLM_F_REQUEST | NLM_F_DUMP);
 538
 539         if (!msg) {
 540                 ctxt.ret = - 1;
 541                 goto out;
 542         }
 543
 544         nlmsg_append(msg, &ifa, sizeof(ifa), 0);
 545
 546         nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, cb_valid_handler, &ctxt);
 547         nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, cb_finish_handler, &ctxt);
 548         nl_cb_err(cb, NL_CB_CUSTOM, cb_error_handler, &ctxt);
 549
 550         nl_send_auto_complete(rtnl_socket, msg);
 551         while (ctxt.pending > 0)
 552                 nl_recvmsgs(rtnl_socket, cb);
 553
 554         nlmsg_free(msg);
 555
 556         if (ctxt.ret <= 0)
 557                 goto out;
 558
 559         time_t now = odhcpd_time();
 560         struct odhcpd_ipaddr *addr = *addrs;
 561
 562         qsort(addr, ctxt.ret, sizeof(*addr), v6 ? prefix6_cmp : prefix_cmp);
 563
 564         for (ssize_t i = 0; i < ctxt.ret; ++i) {
 565                 if (addr[i].preferred < UINT32_MAX - now)
 566                         addr[i].preferred += now;
 567
 568                 if (addr[i].valid < UINT32_MAX - now)
 569                         addr[i].valid += now;
 570         }
 571
 572 out:
 573         nl_cb_put(cb);
 574
 575         return ctxt.ret;
 576 }
 577
 578
 579 int netlink_setup_route(const struct in6_addr *addr, const int prefixlen,
 580                 const int ifindex, const struct in6_addr *gw,
 581                 const uint32_t metric, const bool add)
 582 {
 583         struct nl_msg *msg;
 584         struct rtmsg rtm = {
 585                 .rtm_family = AF_INET6,
 586                 .rtm_dst_len = prefixlen,
 587                 .rtm_src_len = 0,
 588                 .rtm_table = RT_TABLE_MAIN,
 589                 .rtm_protocol = (add ? RTPROT_STATIC : RTPROT_UNSPEC),
 590                 .rtm_scope = (add ? (gw ? RT_SCOPE_UNIVERSE : RT_SCOPE_LINK) : RT_SCOPE_NOWHERE),
 591                 .rtm_type = (add ? RTN_UNICAST : RTN_UNSPEC),
 592         };
 593         int ret = 0;
 594
 595         msg = nlmsg_alloc_simple(add ? RTM_NEWROUTE : RTM_DELROUTE,
 596                                         add ? NLM_F_CREATE | NLM_F_REPLACE : 0);
 597         if (!msg)
 598                 return -1;
 599
 600         nlmsg_append(msg, &rtm, sizeof(rtm), 0);
 601
 602         nla_put(msg, RTA_DST, sizeof(*addr), addr);
 603         nla_put_u32(msg, RTA_OIF, ifindex);
 604         nla_put_u32(msg, RTA_PRIORITY, metric);
 605
 606         if (gw)
 607                 nla_put(msg, RTA_GATEWAY, sizeof(*gw), gw);
 608
 609         ret = nl_send_auto_complete(rtnl_socket, msg);
 610         nlmsg_free(msg);
 611
 612         if (ret < 0)
 613                 return ret;
 614
 615         return nl_wait_for_ack(rtnl_socket);
 616 }
 617
 618
 619 int netlink_setup_proxy_neigh(const struct in6_addr *addr,
 620                 const int ifindex, const bool add)
 621 {
 622         struct nl_msg *msg;
 623         struct ndmsg ndm = {
 624                 .ndm_family = AF_INET6,
 625                 .ndm_flags = NTF_PROXY,
 626                 .ndm_ifindex = ifindex,
 627         };
 628         int ret = 0, flags = NLM_F_REQUEST;
 629
 630         if (add)
 631                 flags |= NLM_F_REPLACE | NLM_F_CREATE;
 632
 633         msg = nlmsg_alloc_simple(add ? RTM_NEWNEIGH : RTM_DELNEIGH, flags);
 634         if (!msg)
 635                 return -1;
 636
 637         nlmsg_append(msg, &ndm, sizeof(ndm), 0);
 638
 639         nla_put(msg, NDA_DST, sizeof(*addr), addr);
 640
 641         ret = nl_send_auto_complete(rtnl_socket, msg);
 642         nlmsg_free(msg);
 643
 644         if (ret < 0)
 645                 return ret;
 646
 647         return nl_wait_for_ack(rtnl_socket);
 648 }
 649
 650
 651 int netlink_setup_addr(struct odhcpd_ipaddr *addr,
 652                 const int ifindex, const bool v6, const bool add)
 653 {
 654         struct nl_msg *msg;
 655         struct ifaddrmsg ifa = {
 656                 .ifa_family = v6 ? AF_INET6 : AF_INET,
 657                 .ifa_prefixlen = addr->prefix,
 658                 .ifa_flags = 0,
 659                 .ifa_scope = 0,
 660                 .ifa_index = ifindex, };
 661         int ret = 0, flags = NLM_F_REQUEST;
 662
 663         if (add)
 664                 flags |= NLM_F_REPLACE | NLM_F_CREATE;
 665
 666         msg = nlmsg_alloc_simple(add ? RTM_NEWADDR : RTM_DELADDR, 0);
 667         if (!msg)
 668                 return -1;
 669
 670         nlmsg_append(msg, &ifa, sizeof(ifa), flags);
 671         nla_put(msg, IFA_LOCAL, v6 ? 16 : 4, &addr->addr);
 672         if (v6) {
 673                 struct ifa_cacheinfo cinfo = {  .ifa_prefered = 0xffffffffU,
 674                                                 .ifa_valid = 0xffffffffU,
 675                                                 .cstamp = 0,
 676                                                 .tstamp = 0 };
 677                 time_t now = odhcpd_time();
 678
 679                 if (addr->preferred) {
 680                         int64_t preferred = addr->preferred - now;
 681                         if (preferred < 0)
 682                                 preferred = 0;
 683                         else if (preferred > UINT32_MAX)
 684                                 preferred = UINT32_MAX;
 685
 686                         cinfo.ifa_prefered = preferred;
 687                 }
 688
 689                 if (addr->valid) {
 690                         int64_t valid = addr->valid - now;
 691                         if (valid <= 0) {
 692                                 nlmsg_free(msg);
 693                                 return -1;
 694                         }
 695                         else if (valid > UINT32_MAX)
 696                                 valid = UINT32_MAX;
 697
 698                         cinfo.ifa_valid = valid;
 699                 }
 700
 701                 nla_put(msg, IFA_CACHEINFO, sizeof(cinfo), &cinfo);
 702
 703                 nla_put_u32(msg, IFA_FLAGS, IFA_F_NOPREFIXROUTE);
 704         } else {
 705                 if (addr->broadcast.s_addr)
 706                         nla_put_u32(msg, IFA_BROADCAST, addr->broadcast.s_addr);
 707         }
 708
 709         ret = nl_send_auto_complete(rtnl_socket, msg);
 710         nlmsg_free(msg);
 711
 712         if (ret < 0)
 713                 return ret;
 714
 715         return nl_wait_for_ack(rtnl_socket);
 716 }
 717
 718 void netlink_dump_neigh_table(const bool proxy)
 719 {
 720         struct nl_msg *msg;
 721         struct ndmsg ndm = {
 722                 .ndm_family = AF_INET6,
 723                 .ndm_flags = proxy ? NTF_PROXY : 0,
 724         };
 725
 726         msg = nlmsg_alloc_simple(RTM_GETNEIGH, NLM_F_REQUEST | NLM_F_DUMP);
 727         if (!msg)
 728                 return;
 729
 730         nlmsg_append(msg, &ndm, sizeof(ndm), 0);
 731
 732         nl_send_auto_complete(rtnl_event.sock, msg);
 733
 734         nlmsg_free(msg);
 735 }
 736
 737 void netlink_dump_addr_table(const bool v6)
 738 {
 739         struct nl_msg *msg;
 740         struct ifaddrmsg ifa = {
 741                 .ifa_family = v6 ? AF_INET6 : AF_INET,
 742         };
 743
 744         msg = nlmsg_alloc_simple(RTM_GETADDR, NLM_F_REQUEST | NLM_F_DUMP);
 745         if (!msg)
 746                 return;
 747
 748         nlmsg_append(msg, &ifa, sizeof(ifa), 0);
 749
 750         nl_send_auto_complete(rtnl_event.sock, msg);
 751
 752         nlmsg_free(msg);
 753 }