system-linux.c

   1 #define _GNU_SOURCE
   2
   3 #include <sys/socket.h>
   4 #include <sys/ioctl.h>
   5 #include <sys/stat.h>
   6 #include <sys/syscall.h>
   7
   8 #include <linux/rtnetlink.h>
   9 #include <linux/sockios.h>
  10 #include <linux/if_vlan.h>
  11 #include <linux/if_bridge.h>
  12
  13 #include <unistd.h>
  14 #include <string.h>
  15 #include <fcntl.h>
  16 #include <glob.h>
  17
  18 #include <netlink/msg.h>
  19 #include <netlink/attr.h>
  20 #include <netlink/socket.h>
  21 #include <libubox/uloop.h>
  22
  23 #include "netifd.h"
  24 #include "device.h"
  25 #include "system.h"
  26
  27 struct event_socket {
  28         struct uloop_fd uloop;
  29         struct nl_sock *sock;
  30         struct nl_cb *cb;
  31 };
  32
  33 static int sock_ioctl = -1;
  34 static struct nl_sock *sock_rtnl = NULL;
  35
  36 static int cb_rtnl_event(struct nl_msg *msg, void *arg);
  37
  38 static void handler_nl_event(struct uloop_fd *u, unsigned int events)
  39 {
  40         struct event_socket *ev = container_of(u, struct event_socket, uloop);
  41         nl_recvmsgs(ev->sock, ev->cb);
  42 }
  43
  44 int system_init(void)
  45 {
  46         static struct event_socket rtnl_event = {
  47                 .uloop.cb = handler_nl_event,
  48         };
  49
  50         sock_ioctl = socket(AF_LOCAL, SOCK_DGRAM, 0);
  51         fcntl(sock_ioctl, F_SETFD, fcntl(sock_ioctl, F_GETFD) | FD_CLOEXEC);
  52
  53         // Prepare socket for routing / address control
  54         sock_rtnl = nl_socket_alloc();
  55         if (!sock_rtnl)
  56                 return -1;
  57
  58         if (nl_connect(sock_rtnl, NETLINK_ROUTE))
  59                 return -1;
  60
  61         // Prepare socket for link events
  62         rtnl_event.cb = nl_cb_alloc(NL_CB_DEFAULT);
  63         if (!rtnl_event.cb)
  64                 return -1;
  65
  66         nl_cb_set(rtnl_event.cb, NL_CB_VALID, NL_CB_CUSTOM,
  67                   cb_rtnl_event, NULL);
  68
  69         rtnl_event.sock = nl_socket_alloc();
  70         if (!rtnl_event.sock)
  71                 return -1;
  72
  73         if (nl_connect(rtnl_event.sock, NETLINK_ROUTE))
  74                 return -1;
  75
  76         // Receive network link events form kernel
  77         nl_socket_add_membership(rtnl_event.sock, RTNLGRP_LINK);
  78
  79         rtnl_event.uloop.fd = nl_socket_get_fd(rtnl_event.sock);
  80         uloop_fd_add(&rtnl_event.uloop, ULOOP_READ | ULOOP_EDGE_TRIGGER);
  81
  82         return 0;
  83 }
  84
  85 static void system_set_sysctl(const char *path, const char *val)
  86 {
  87         int fd;
  88
  89         fd = open(path, O_WRONLY);
  90         if (fd < 0)
  91                 return;
  92
  93         write(fd, val, strlen(val));
  94         close(fd);
  95 }
  96
  97 static void system_set_dev_sysctl(const char *path, const char *device, const char *val)
  98 {
  99         static char buf[256];
 100
 101         snprintf(buf, sizeof(buf), path, val);
 102         system_set_sysctl(buf, val);
 103 }
 104
 105 static void system_set_disable_ipv6(struct device *dev, const char *val)
 106 {
 107         system_set_dev_sysctl("/proc/sys/net/ipv6/conf/%s/disable_ipv6", dev->ifname, val);
 108 }
 109
 110 // Evaluate netlink messages
 111 static int cb_rtnl_event(struct nl_msg *msg, void *arg)
 112 {
 113         struct nlmsghdr *nh = nlmsg_hdr(msg);
 114         struct ifinfomsg *ifi = NLMSG_DATA(nh);
 115         struct nlattr *nla[__IFLA_MAX];
 116
 117         if (nh->nlmsg_type != RTM_DELLINK && nh->nlmsg_type != RTM_NEWLINK)
 118                 goto out;
 119
 120         nlmsg_parse(nh, sizeof(*ifi), nla, __IFLA_MAX - 1, NULL);
 121         if (!nla[IFLA_IFNAME])
 122                 goto out;
 123
 124         struct device *dev = device_get(RTA_DATA(nla[IFLA_IFNAME]), false);
 125         if (!dev)
 126                 goto out;
 127
 128         dev->ifindex = ifi->ifi_index;
 129         device_set_present(dev, (nh->nlmsg_type == RTM_NEWLINK));
 130
 131 out:
 132         return 0;
 133 }
 134
 135 static int system_rtnl_call(struct nl_msg *msg)
 136 {
 137         int s = -(nl_send_auto_complete(sock_rtnl, msg)
 138                         || nl_wait_for_ack(sock_rtnl));
 139         nlmsg_free(msg);
 140         return s;
 141 }
 142
 143 int system_bridge_delbr(struct device *bridge)
 144 {
 145         return ioctl(sock_ioctl, SIOCBRDELBR, bridge->ifname);
 146 }
 147
 148 static int system_bridge_if(const char *bridge, struct device *dev, int cmd, void *data)
 149 {
 150         struct ifreq ifr;
 151         if (dev)
 152                 ifr.ifr_ifindex = dev->ifindex;
 153         else
 154                 ifr.ifr_data = data;
 155         strncpy(ifr.ifr_name, bridge, sizeof(ifr.ifr_name));
 156         return ioctl(sock_ioctl, cmd, &ifr);
 157 }
 158
 159 int system_bridge_addif(struct device *bridge, struct device *dev)
 160 {
 161         system_set_disable_ipv6(dev, "1");
 162         return system_bridge_if(bridge->ifname, dev, SIOCBRADDIF, NULL);
 163 }
 164
 165 int system_bridge_delif(struct device *bridge, struct device *dev)
 166 {
 167         system_set_disable_ipv6(dev, "0");
 168         return system_bridge_if(bridge->ifname, dev, SIOCBRDELIF, NULL);
 169 }
 170
 171 static bool system_is_bridge(const char *name, char *buf, int buflen)
 172 {
 173         struct stat st;
 174
 175         snprintf(buf, buflen, "/sys/devices/virtual/net/%s/bridge", name);
 176         if (stat(buf, &st) < 0)
 177                 return false;
 178
 179         return true;
 180 }
 181
 182 static char *system_get_bridge(const char *name, char *buf, int buflen)
 183 {
 184         char *path;
 185         ssize_t len;
 186         glob_t gl;
 187
 188         snprintf(buf, buflen, "/sys/devices/virtual/net/*/brif/%s/bridge", name);
 189         if (glob(buf, GLOB_NOSORT, NULL, &gl) < 0)
 190                 return NULL;
 191
 192         if (gl.gl_pathc == 0)
 193                 return NULL;
 194
 195         len = readlink(gl.gl_pathv[0], buf, buflen);
 196         if (len < 0)
 197                 return NULL;
 198
 199         buf[len] = 0;
 200         path = strrchr(buf, '/');
 201         if (!path)
 202                 return NULL;
 203
 204         return path + 1;
 205 }
 206
 207 static int system_if_resolve(struct device *dev)
 208 {
 209         struct ifreq ifr;
 210         strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
 211         if (!ioctl(sock_ioctl, SIOCGIFINDEX, &ifr))
 212                 return ifr.ifr_ifindex;
 213         else
 214                 return 0;
 215 }
 216
 217 static int system_if_flags(const char *ifname, unsigned add, unsigned rem)
 218 {
 219         struct ifreq ifr;
 220         strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
 221         ioctl(sock_ioctl, SIOCGIFFLAGS, &ifr);
 222         ifr.ifr_flags |= add;
 223         ifr.ifr_flags &= ~rem;
 224         return ioctl(sock_ioctl, SIOCSIFFLAGS, &ifr);
 225 }
 226
 227 struct clear_data {
 228         struct nl_msg *msg;
 229         struct device *dev;
 230         int type;
 231         int size;
 232         int af;
 233 };
 234
 235
 236 static bool check_ifaddr(struct nlmsghdr *hdr, int ifindex)
 237 {
 238         struct ifaddrmsg *ifa = NLMSG_DATA(hdr);
 239
 240         return ifa->ifa_index == ifindex;
 241 }
 242
 243 static bool check_route(struct nlmsghdr *hdr, int ifindex)
 244 {
 245         struct nlattr *tb[__RTA_MAX];
 246
 247         nlmsg_parse(hdr, sizeof(struct rtmsg), tb, __RTA_MAX - 1, NULL);
 248         if (!tb[RTA_OIF])
 249                 return false;
 250
 251         return *(int *)RTA_DATA(tb[RTA_OIF]) == ifindex;
 252 }
 253
 254 static int cb_clear_event(struct nl_msg *msg, void *arg)
 255 {
 256         struct clear_data *clr = arg;
 257         struct nlmsghdr *hdr = nlmsg_hdr(msg);
 258         bool (*cb)(struct nlmsghdr *, int ifindex);
 259         int type;
 260
 261         switch(clr->type) {
 262         case RTM_GETADDR:
 263                 type = RTM_DELADDR;
 264                 if (hdr->nlmsg_type != RTM_NEWADDR)
 265                         return NL_SKIP;
 266
 267                 cb = check_ifaddr;
 268                 break;
 269         case RTM_GETROUTE:
 270                 type = RTM_DELROUTE;
 271                 if (hdr->nlmsg_type != RTM_NEWROUTE)
 272                         return NL_SKIP;
 273
 274                 cb = check_route;
 275                 break;
 276         default:
 277                 return NL_SKIP;
 278         }
 279
 280         if (!cb(hdr, clr->dev->ifindex))
 281                 return NL_SKIP;
 282
 283         D(SYSTEM, "Remove %s from device %s\n",
 284           type == RTM_DELADDR ? "an address" : "a route",
 285           clr->dev->ifname);
 286         memcpy(nlmsg_hdr(clr->msg), hdr, hdr->nlmsg_len);
 287         hdr = nlmsg_hdr(clr->msg);
 288         hdr->nlmsg_type = type;
 289         hdr->nlmsg_flags = NLM_F_REQUEST;
 290
 291         if (!nl_send_auto_complete(sock_rtnl, clr->msg))
 292                 nl_wait_for_ack(sock_rtnl);
 293
 294         return NL_SKIP;
 295 }
 296
 297 static int
 298 cb_finish_event(struct nl_msg *msg, void *arg)
 299 {
 300         int *pending = arg;
 301         *pending = 0;
 302         return NL_STOP;
 303 }
 304
 305 static int
 306 error_handler(struct sockaddr_nl *nla, struct nlmsgerr *err, void *arg)
 307 {
 308         int *pending = arg;
 309         *pending = err->error;
 310         return NL_STOP;
 311 }
 312
 313 static void
 314 system_if_clear_entries(struct device *dev, int type, int af)
 315 {
 316         struct clear_data clr;
 317         struct nl_cb *cb = nl_cb_alloc(NL_CB_DEFAULT);
 318         struct rtmsg rtm = {
 319                 .rtm_family = af,
 320                 .rtm_flags = RTM_F_CLONED,
 321         };
 322         int flags = NLM_F_DUMP;
 323         int pending = 1;
 324
 325         clr.af = af;
 326         clr.dev = dev;
 327         clr.type = type;
 328         switch (type) {
 329         case RTM_GETADDR:
 330                 clr.size = sizeof(struct rtgenmsg);
 331                 break;
 332         case RTM_GETROUTE:
 333                 clr.size = sizeof(struct rtmsg);
 334                 break;
 335         default:
 336                 return;
 337         }
 338
 339         if (!cb)
 340                 return;
 341
 342         clr.msg = nlmsg_alloc_simple(type, flags);
 343         if (!clr.msg)
 344                 goto out;
 345
 346         nlmsg_append(clr.msg, &rtm, clr.size, 0);
 347         nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, cb_clear_event, &clr);
 348         nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, cb_finish_event, &pending);
 349         nl_cb_err(cb, NL_CB_CUSTOM, error_handler, &pending);
 350
 351         nl_send_auto_complete(sock_rtnl, clr.msg);
 352         while (pending > 0)
 353                 nl_recvmsgs(sock_rtnl, cb);
 354
 355         nlmsg_free(clr.msg);
 356 out:
 357         nl_cb_put(cb);
 358 }
 359
 360 /*
 361  * Clear bridge (membership) state and bring down device
 362  */
 363 void system_if_clear_state(struct device *dev)
 364 {
 365         static char buf[256];
 366         char *bridge;
 367
 368         if (dev->external)
 369                 return;
 370
 371         dev->ifindex = system_if_resolve(dev);
 372         if (!dev->ifindex)
 373                 return;
 374
 375         system_if_flags(dev->ifname, 0, IFF_UP);
 376
 377         if (system_is_bridge(dev->ifname, buf, sizeof(buf))) {
 378                 D(SYSTEM, "Delete existing bridge named '%s'\n", dev->ifname);
 379                 system_bridge_delbr(dev);
 380                 return;
 381         }
 382
 383         bridge = system_get_bridge(dev->ifname, buf, sizeof(buf));
 384         if (bridge) {
 385                 D(SYSTEM, "Remove device '%s' from bridge '%s'\n", dev->ifname, bridge);
 386                 system_bridge_if(bridge, dev, SIOCBRDELIF, NULL);
 387         }
 388
 389         system_if_clear_entries(dev, RTM_GETROUTE, AF_INET);
 390         system_if_clear_entries(dev, RTM_GETADDR, AF_INET);
 391         system_if_clear_entries(dev, RTM_GETROUTE, AF_INET6);
 392         system_if_clear_entries(dev, RTM_GETADDR, AF_INET6);
 393         system_set_disable_ipv6(dev, "0");
 394 }
 395
 396 static inline unsigned long
 397 sec_to_jiffies(int val)
 398 {
 399         return (unsigned long) val * 100;
 400 }
 401
 402 int system_bridge_addbr(struct device *bridge, struct bridge_config *cfg)
 403 {
 404         unsigned long args[4] = {};
 405
 406         if (ioctl(sock_ioctl, SIOCBRADDBR, bridge->ifname) < 0)
 407                 return -1;
 408
 409         args[0] = BRCTL_SET_BRIDGE_STP_STATE;
 410         args[1] = !!cfg->stp;
 411         system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
 412
 413         args[0] = BRCTL_SET_BRIDGE_FORWARD_DELAY;
 414         args[1] = sec_to_jiffies(cfg->forward_delay);
 415         system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
 416
 417         system_set_dev_sysctl("/sys/devices/virtual/net/%s/bridge/multicast_snooping",
 418                 bridge->ifname, cfg->igmp_snoop ? "1" : "0");
 419
 420         if (cfg->flags & BRIDGE_OPT_AGEING_TIME) {
 421                 args[0] = BRCTL_SET_AGEING_TIME;
 422                 args[1] = sec_to_jiffies(cfg->ageing_time);
 423                 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
 424         }
 425
 426         if (cfg->flags & BRIDGE_OPT_HELLO_TIME) {
 427                 args[0] = BRCTL_SET_BRIDGE_HELLO_TIME;
 428                 args[1] = sec_to_jiffies(cfg->hello_time);
 429                 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
 430         }
 431
 432         if (cfg->flags & BRIDGE_OPT_MAX_AGE) {
 433                 args[0] = BRCTL_SET_BRIDGE_MAX_AGE;
 434                 args[1] = sec_to_jiffies(cfg->max_age);
 435                 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
 436         }
 437
 438         return 0;
 439 }
 440
 441 static int system_vlan(struct device *dev, int id)
 442 {
 443         struct vlan_ioctl_args ifr = {
 444                 .cmd = SET_VLAN_NAME_TYPE_CMD,
 445                 .u.name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD,
 446         };
 447
 448         ioctl(sock_ioctl, SIOCSIFVLAN, &ifr);
 449
 450         if (id < 0) {
 451                 ifr.cmd = DEL_VLAN_CMD;
 452                 ifr.u.VID = 0;
 453         } else {
 454                 ifr.cmd = ADD_VLAN_CMD;
 455                 ifr.u.VID = id;
 456         }
 457         strncpy(ifr.device1, dev->ifname, sizeof(ifr.device1));
 458         return ioctl(sock_ioctl, SIOCSIFVLAN, &ifr);
 459 }
 460
 461 int system_vlan_add(struct device *dev, int id)
 462 {
 463         return system_vlan(dev, id);
 464 }
 465
 466 int system_vlan_del(struct device *dev)
 467 {
 468         return system_vlan(dev, -1);
 469 }
 470
 471 static void
 472 system_if_apply_settings(struct device *dev)
 473 {
 474         struct ifreq ifr;
 475
 476         memset(&ifr, 0, sizeof(ifr));
 477         strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
 478         if (dev->flags & DEV_OPT_MTU) {
 479                 ifr.ifr_mtu = dev->mtu;
 480                 ioctl(sock_ioctl, SIOCSIFMTU, &ifr);
 481         }
 482         if (dev->flags & DEV_OPT_TXQUEUELEN) {
 483                 ifr.ifr_qlen = dev->txqueuelen;
 484                 ioctl(sock_ioctl, SIOCSIFTXQLEN, &ifr);
 485         }
 486         if (dev->flags & DEV_OPT_MACADDR) {
 487                 memcpy(&ifr.ifr_hwaddr, dev->macaddr, sizeof(dev->macaddr));
 488                 ioctl(sock_ioctl, SIOCSIFHWADDR, &ifr);
 489         }
 490
 491         dev->ifindex = system_if_resolve(dev);
 492 }
 493
 494 int system_if_up(struct device *dev)
 495 {
 496         system_if_apply_settings(dev);
 497         return system_if_flags(dev->ifname, IFF_UP, 0);
 498 }
 499
 500 int system_if_down(struct device *dev)
 501 {
 502         return system_if_flags(dev->ifname, 0, IFF_UP);
 503 }
 504
 505 int system_if_check(struct device *dev)
 506 {
 507         device_set_present(dev, (system_if_resolve(dev) >= 0));
 508         return 0;
 509 }
 510
 511 int system_if_dump_stats(struct device *dev, struct blob_buf *b)
 512 {
 513         const char *const counters[] = {
 514                 "collisions",     "rx_frame_errors",   "tx_compressed",
 515                 "multicast",      "rx_length_errors",  "tx_dropped",
 516                 "rx_bytes",       "rx_missed_errors",  "tx_errors",
 517                 "rx_compressed",  "rx_over_errors",    "tx_fifo_errors",
 518                 "rx_crc_errors",  "rx_packets",        "tx_heartbeat_errors",
 519                 "rx_dropped",     "tx_aborted_errors", "tx_packets",
 520                 "rx_errors",      "tx_bytes",          "tx_window_errors",
 521                 "rx_fifo_errors", "tx_carrier_errors",
 522         };
 523         char buf[64];
 524         int stats_dir;
 525         int i, fd, len;
 526
 527         snprintf(buf, sizeof(buf), "/sys/class/net/%s/statistics", dev->ifname);
 528         stats_dir = open(buf, O_DIRECTORY);
 529         if (stats_dir < 0)
 530                 return -1;
 531
 532         for (i = 0; i < ARRAY_SIZE(counters); i++) {
 533                 fd = openat(stats_dir, counters[i], O_RDONLY);
 534                 if (fd < 0)
 535                         continue;
 536
 537 retry:
 538                 len = read(fd, buf, sizeof(buf));
 539                 if (len < 0) {
 540                         if (errno == EINTR)
 541                                 goto retry;
 542                         continue;
 543                 }
 544
 545                 buf[len] = 0;
 546                 blobmsg_add_u32(b, counters[i], strtoul(buf, NULL, 0));
 547                 close(fd);
 548         }
 549
 550         close(stats_dir);
 551         return 0;
 552 }
 553
 554 static int system_addr(struct device *dev, struct device_addr *addr, int cmd)
 555 {
 556         int alen = ((addr->flags & DEVADDR_FAMILY) == DEVADDR_INET4) ? 4 : 16;
 557         struct ifaddrmsg ifa = {
 558                 .ifa_family = (alen == 4) ? AF_INET : AF_INET6,
 559                 .ifa_prefixlen = addr->mask,
 560                 .ifa_index = dev->ifindex,
 561         };
 562
 563         struct nl_msg *msg;
 564
 565         dev = addr->device;
 566         if (dev) {
 567                 if (!dev->ifindex)
 568                         return -1;
 569
 570                 ifa.ifa_index = dev->ifindex;
 571         }
 572
 573         msg = nlmsg_alloc_simple(cmd, 0);
 574         if (!msg)
 575                 return -1;
 576
 577         nlmsg_append(msg, &ifa, sizeof(ifa), 0);
 578         nla_put(msg, IFA_LOCAL, alen, &addr->addr);
 579         return system_rtnl_call(msg);
 580 }
 581
 582 int system_add_address(struct device *dev, struct device_addr *addr)
 583 {
 584         return system_addr(dev, addr, RTM_NEWADDR);
 585 }
 586
 587 int system_del_address(struct device *dev, struct device_addr *addr)
 588 {
 589         return system_addr(dev, addr, RTM_DELADDR);
 590 }
 591
 592 static int system_rt(struct device *dev, struct device_route *route, int cmd)
 593 {
 594         int alen = ((route->flags & DEVADDR_FAMILY) == DEVADDR_INET4) ? 4 : 16;
 595         bool have_gw;
 596         unsigned int flags = 0;
 597         int ifindex = dev->ifindex;
 598
 599         if (alen == 4)
 600                 have_gw = !!route->nexthop.in.s_addr;
 601         else
 602                 have_gw = route->nexthop.in6.s6_addr32[0] ||
 603                         route->nexthop.in6.s6_addr32[1] ||
 604                         route->nexthop.in6.s6_addr32[2] ||
 605                         route->nexthop.in6.s6_addr32[3];
 606
 607         unsigned char scope = (cmd == RTM_DELROUTE) ? RT_SCOPE_NOWHERE :
 608                         (have_gw) ? RT_SCOPE_UNIVERSE : RT_SCOPE_LINK;
 609
 610         struct rtmsg rtm = {
 611                 .rtm_family = (alen == 4) ? AF_INET : AF_INET6,
 612                 .rtm_dst_len = route->mask,
 613                 .rtm_table = RT_TABLE_MAIN,
 614                 .rtm_protocol = RTPROT_BOOT,
 615                 .rtm_scope = scope,
 616                 .rtm_type = (cmd == RTM_DELROUTE) ? 0: RTN_UNICAST,
 617         };
 618         struct nl_msg *msg;
 619
 620         if (cmd == RTM_NEWROUTE)
 621                 flags |= NLM_F_CREATE | NLM_F_REPLACE;
 622
 623         dev = route->device;
 624         if (dev) {
 625                 if (!dev->ifindex)
 626                         return -1;
 627
 628                 ifindex = dev->ifindex;
 629         }
 630
 631         msg = nlmsg_alloc_simple(cmd, flags);
 632         if (!msg)
 633                 return -1;
 634
 635         nlmsg_append(msg, &rtm, sizeof(rtm), 0);
 636
 637         if (route->mask)
 638                 nla_put(msg, RTA_DST, alen, &route->addr);
 639
 640         if (have_gw)
 641                 nla_put(msg, RTA_GATEWAY, alen, &route->nexthop);
 642
 643         if (route->flags & DEVADDR_DEVICE)
 644                 nla_put_u32(msg, RTA_OIF, ifindex);
 645
 646         return system_rtnl_call(msg);
 647 }
 648
 649 int system_add_route(struct device *dev, struct device_route *route)
 650 {
 651         return system_rt(dev, route, RTM_NEWROUTE);
 652 }
 653
 654 int system_del_route(struct device *dev, struct device_route *route)
 655 {
 656         return system_rt(dev, route, RTM_DELROUTE);
 657 }
 658
 659 int system_flush_routes(void)
 660 {
 661         const char *names[] = {
 662                 "/proc/sys/net/ipv4/route/flush",
 663                 "/proc/sys/net/ipv6/route/flush"
 664         };
 665         int fd, i;
 666
 667         for (i = 0; i < ARRAY_SIZE(names); i++) {
 668                 fd = open(names[i], O_WRONLY);
 669                 if (fd < 0)
 670                         continue;
 671
 672                 write(fd, "-1", 2);
 673                 close(fd);
 674         }
 675         return 0;
 676 }
 677
 678 time_t system_get_rtime(void)
 679 {
 680         struct timespec ts;
 681         struct timeval tv;
 682
 683         if (syscall(__NR_clock_gettime, CLOCK_MONOTONIC, &ts) == 0)
 684                 return ts.tv_sec;
 685
 686         if (gettimeofday(&tv, NULL) == 0)
 687                 return tv.tv_sec;
 688
 689         return 0;
 690 }