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 #include <linux/ethtool.h>
  13
  14 #include <unistd.h>
  15 #include <string.h>
  16 #include <fcntl.h>
  17 #include <glob.h>
  18 #include <time.h>
  19
  20 #include <netlink/msg.h>
  21 #include <netlink/attr.h>
  22 #include <netlink/socket.h>
  23 #include <libubox/uloop.h>
  24
  25 #include "netifd.h"
  26 #include "device.h"
  27 #include "system.h"
  28
  29 struct event_socket {
  30         struct uloop_fd uloop;
  31         struct nl_sock *sock;
  32         struct nl_cb *cb;
  33 };
  34
  35 static int sock_ioctl = -1;
  36 static struct nl_sock *sock_rtnl = NULL;
  37
  38 static int cb_rtnl_event(struct nl_msg *msg, void *arg);
  39 static void handle_hotplug_event(struct uloop_fd *u, unsigned int events);
  40
  41 static void
  42 handler_nl_event(struct uloop_fd *u, unsigned int events)
  43 {
  44         struct event_socket *ev = container_of(u, struct event_socket, uloop);
  45         nl_recvmsgs(ev->sock, ev->cb);
  46 }
  47
  48 static struct nl_sock *
  49 create_socket(int protocol, int groups)
  50 {
  51         struct nl_sock *sock;
  52
  53         sock = nl_socket_alloc();
  54         if (!sock)
  55                 return NULL;
  56
  57         if (groups)
  58                 nl_join_groups(sock, groups);
  59
  60         if (nl_connect(sock, protocol))
  61                 return NULL;
  62
  63         return sock;
  64 }
  65
  66 static bool
  67 create_raw_event_socket(struct event_socket *ev, int protocol, int groups,
  68                         uloop_fd_handler cb)
  69 {
  70         ev->sock = create_socket(protocol, groups);
  71         if (!ev->sock)
  72                 return false;
  73
  74         ev->uloop.fd = nl_socket_get_fd(ev->sock);
  75         ev->uloop.cb = cb;
  76         uloop_fd_add(&ev->uloop, ULOOP_READ | ULOOP_EDGE_TRIGGER);
  77         return true;
  78 }
  79
  80 static bool
  81 create_event_socket(struct event_socket *ev, int protocol,
  82                     int (*cb)(struct nl_msg *msg, void *arg))
  83 {
  84         // Prepare socket for link events
  85         ev->cb = nl_cb_alloc(NL_CB_DEFAULT);
  86         if (!ev->cb)
  87                 return false;
  88
  89         nl_cb_set(ev->cb, NL_CB_VALID, NL_CB_CUSTOM, cb, NULL);
  90
  91         return create_raw_event_socket(ev, protocol, 0, handler_nl_event);
  92 }
  93
  94 int system_init(void)
  95 {
  96         static struct event_socket rtnl_event;
  97         static struct event_socket hotplug_event;
  98
  99         sock_ioctl = socket(AF_LOCAL, SOCK_DGRAM, 0);
 100         fcntl(sock_ioctl, F_SETFD, fcntl(sock_ioctl, F_GETFD) | FD_CLOEXEC);
 101
 102         // Prepare socket for routing / address control
 103         sock_rtnl = create_socket(NETLINK_ROUTE, 0);
 104         if (!sock_rtnl)
 105                 return -1;
 106
 107         if (!create_event_socket(&rtnl_event, NETLINK_ROUTE, cb_rtnl_event))
 108                 return -1;
 109
 110         if (!create_raw_event_socket(&hotplug_event, NETLINK_KOBJECT_UEVENT, 1,
 111                                      handle_hotplug_event))
 112                 return -1;
 113
 114         // Receive network link events form kernel
 115         nl_socket_add_membership(rtnl_event.sock, RTNLGRP_LINK);
 116
 117         return 0;
 118 }
 119
 120 static void system_set_sysctl(const char *path, const char *val)
 121 {
 122         int fd;
 123
 124         fd = open(path, O_WRONLY);
 125         if (fd < 0)
 126                 return;
 127
 128         write(fd, val, strlen(val));
 129         close(fd);
 130 }
 131
 132 static void system_set_dev_sysctl(const char *path, const char *device, const char *val)
 133 {
 134         static char buf[256];
 135
 136         snprintf(buf, sizeof(buf), path, val);
 137         system_set_sysctl(buf, val);
 138 }
 139
 140 static void system_set_disable_ipv6(struct device *dev, const char *val)
 141 {
 142         system_set_dev_sysctl("/proc/sys/net/ipv6/conf/%s/disable_ipv6", dev->ifname, val);
 143 }
 144
 145 // Evaluate netlink messages
 146 static int cb_rtnl_event(struct nl_msg *msg, void *arg)
 147 {
 148         struct nlmsghdr *nh = nlmsg_hdr(msg);
 149         struct ifinfomsg *ifi = NLMSG_DATA(nh);
 150         struct nlattr *nla[__IFLA_MAX];
 151
 152         if (nh->nlmsg_type != RTM_DELLINK && nh->nlmsg_type != RTM_NEWLINK)
 153                 goto out;
 154
 155         nlmsg_parse(nh, sizeof(*ifi), nla, __IFLA_MAX - 1, NULL);
 156         if (!nla[IFLA_IFNAME])
 157                 goto out;
 158
 159         struct device *dev = device_get(RTA_DATA(nla[IFLA_IFNAME]), false);
 160         if (!dev)
 161                 goto out;
 162
 163         dev->ifindex = ifi->ifi_index;
 164         /* TODO: parse link status */
 165
 166 out:
 167         return 0;
 168 }
 169
 170 static void
 171 handle_hotplug_msg(char *data, int size)
 172 {
 173         const char *subsystem = NULL, *interface = NULL;
 174         char *cur, *end, *sep;
 175         struct device *dev;
 176         int skip;
 177         bool add;
 178
 179         if (!strncmp(data, "add@", 4))
 180                 add = true;
 181         else if (!strncmp(data, "remove@", 7))
 182                 add = false;
 183         else
 184                 return;
 185
 186         skip = strlen(data) + 1;
 187         end = data + size;
 188
 189         for (cur = data + skip; cur < end; cur += skip) {
 190                 skip = strlen(cur) + 1;
 191
 192                 sep = strchr(cur, '=');
 193                 if (!sep)
 194                         continue;
 195
 196                 *sep = 0;
 197                 if (!strcmp(cur, "INTERFACE"))
 198                         interface = sep + 1;
 199                 else if (!strcmp(cur, "SUBSYSTEM")) {
 200                         subsystem = sep + 1;
 201                         if (strcmp(subsystem, "net") != 0)
 202                                 return;
 203                 }
 204                 if (subsystem && interface)
 205                         goto found;
 206         }
 207         return;
 208
 209 found:
 210         dev = device_get(interface, false);
 211         if (!dev)
 212                 return;
 213
 214         if (dev->type != &simple_device_type)
 215                 return;
 216
 217         device_set_present(dev, add);
 218 }
 219
 220 static void
 221 handle_hotplug_event(struct uloop_fd *u, unsigned int events)
 222 {
 223         struct event_socket *ev = container_of(u, struct event_socket, uloop);
 224         struct sockaddr_nl nla;
 225         unsigned char *buf = NULL;
 226         int size;
 227
 228         while ((size = nl_recv(ev->sock, &nla, &buf, NULL)) > 0) {
 229                 if (nla.nl_pid == 0)
 230                         handle_hotplug_msg((char *) buf, size);
 231
 232                 free(buf);
 233         }
 234 }
 235
 236 static int system_rtnl_call(struct nl_msg *msg)
 237 {
 238         int s = -(nl_send_auto_complete(sock_rtnl, msg)
 239                         || nl_wait_for_ack(sock_rtnl));
 240         nlmsg_free(msg);
 241         return s;
 242 }
 243
 244 int system_bridge_delbr(struct device *bridge)
 245 {
 246         return ioctl(sock_ioctl, SIOCBRDELBR, bridge->ifname);
 247 }
 248
 249 static int system_bridge_if(const char *bridge, struct device *dev, int cmd, void *data)
 250 {
 251         struct ifreq ifr;
 252         if (dev)
 253                 ifr.ifr_ifindex = dev->ifindex;
 254         else
 255                 ifr.ifr_data = data;
 256         strncpy(ifr.ifr_name, bridge, sizeof(ifr.ifr_name));
 257         return ioctl(sock_ioctl, cmd, &ifr);
 258 }
 259
 260 int system_bridge_addif(struct device *bridge, struct device *dev)
 261 {
 262         system_set_disable_ipv6(dev, "1");
 263         return system_bridge_if(bridge->ifname, dev, SIOCBRADDIF, NULL);
 264 }
 265
 266 int system_bridge_delif(struct device *bridge, struct device *dev)
 267 {
 268         system_set_disable_ipv6(dev, "0");
 269         return system_bridge_if(bridge->ifname, dev, SIOCBRDELIF, NULL);
 270 }
 271
 272 static bool system_is_bridge(const char *name, char *buf, int buflen)
 273 {
 274         struct stat st;
 275
 276         snprintf(buf, buflen, "/sys/devices/virtual/net/%s/bridge", name);
 277         if (stat(buf, &st) < 0)
 278                 return false;
 279
 280         return true;
 281 }
 282
 283 static char *system_get_bridge(const char *name, char *buf, int buflen)
 284 {
 285         char *path;
 286         ssize_t len;
 287         glob_t gl;
 288
 289         snprintf(buf, buflen, "/sys/devices/virtual/net/*/brif/%s/bridge", name);
 290         if (glob(buf, GLOB_NOSORT, NULL, &gl) < 0)
 291                 return NULL;
 292
 293         if (gl.gl_pathc == 0)
 294                 return NULL;
 295
 296         len = readlink(gl.gl_pathv[0], buf, buflen);
 297         if (len < 0)
 298                 return NULL;
 299
 300         buf[len] = 0;
 301         path = strrchr(buf, '/');
 302         if (!path)
 303                 return NULL;
 304
 305         return path + 1;
 306 }
 307
 308 static int system_if_resolve(struct device *dev)
 309 {
 310         struct ifreq ifr;
 311         strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
 312         if (!ioctl(sock_ioctl, SIOCGIFINDEX, &ifr))
 313                 return ifr.ifr_ifindex;
 314         else
 315                 return 0;
 316 }
 317
 318 static int system_if_flags(const char *ifname, unsigned add, unsigned rem)
 319 {
 320         struct ifreq ifr;
 321         strncpy(ifr.ifr_name, ifname, sizeof(ifr.ifr_name));
 322         ioctl(sock_ioctl, SIOCGIFFLAGS, &ifr);
 323         ifr.ifr_flags |= add;
 324         ifr.ifr_flags &= ~rem;
 325         return ioctl(sock_ioctl, SIOCSIFFLAGS, &ifr);
 326 }
 327
 328 struct clear_data {
 329         struct nl_msg *msg;
 330         struct device *dev;
 331         int type;
 332         int size;
 333         int af;
 334 };
 335
 336
 337 static bool check_ifaddr(struct nlmsghdr *hdr, int ifindex)
 338 {
 339         struct ifaddrmsg *ifa = NLMSG_DATA(hdr);
 340
 341         return ifa->ifa_index == ifindex;
 342 }
 343
 344 static bool check_route(struct nlmsghdr *hdr, int ifindex)
 345 {
 346         struct nlattr *tb[__RTA_MAX];
 347
 348         nlmsg_parse(hdr, sizeof(struct rtmsg), tb, __RTA_MAX - 1, NULL);
 349         if (!tb[RTA_OIF])
 350                 return false;
 351
 352         return *(int *)RTA_DATA(tb[RTA_OIF]) == ifindex;
 353 }
 354
 355 static int cb_clear_event(struct nl_msg *msg, void *arg)
 356 {
 357         struct clear_data *clr = arg;
 358         struct nlmsghdr *hdr = nlmsg_hdr(msg);
 359         bool (*cb)(struct nlmsghdr *, int ifindex);
 360         int type;
 361
 362         switch(clr->type) {
 363         case RTM_GETADDR:
 364                 type = RTM_DELADDR;
 365                 if (hdr->nlmsg_type != RTM_NEWADDR)
 366                         return NL_SKIP;
 367
 368                 cb = check_ifaddr;
 369                 break;
 370         case RTM_GETROUTE:
 371                 type = RTM_DELROUTE;
 372                 if (hdr->nlmsg_type != RTM_NEWROUTE)
 373                         return NL_SKIP;
 374
 375                 cb = check_route;
 376                 break;
 377         default:
 378                 return NL_SKIP;
 379         }
 380
 381         if (!cb(hdr, clr->dev->ifindex))
 382                 return NL_SKIP;
 383
 384         D(SYSTEM, "Remove %s from device %s\n",
 385           type == RTM_DELADDR ? "an address" : "a route",
 386           clr->dev->ifname);
 387         memcpy(nlmsg_hdr(clr->msg), hdr, hdr->nlmsg_len);
 388         hdr = nlmsg_hdr(clr->msg);
 389         hdr->nlmsg_type = type;
 390         hdr->nlmsg_flags = NLM_F_REQUEST;
 391
 392         if (!nl_send_auto_complete(sock_rtnl, clr->msg))
 393                 nl_wait_for_ack(sock_rtnl);
 394
 395         return NL_SKIP;
 396 }
 397
 398 static int
 399 cb_finish_event(struct nl_msg *msg, void *arg)
 400 {
 401         int *pending = arg;
 402         *pending = 0;
 403         return NL_STOP;
 404 }
 405
 406 static int
 407 error_handler(struct sockaddr_nl *nla, struct nlmsgerr *err, void *arg)
 408 {
 409         int *pending = arg;
 410         *pending = err->error;
 411         return NL_STOP;
 412 }
 413
 414 static void
 415 system_if_clear_entries(struct device *dev, int type, int af)
 416 {
 417         struct clear_data clr;
 418         struct nl_cb *cb = nl_cb_alloc(NL_CB_DEFAULT);
 419         struct rtmsg rtm = {
 420                 .rtm_family = af,
 421                 .rtm_flags = RTM_F_CLONED,
 422         };
 423         int flags = NLM_F_DUMP;
 424         int pending = 1;
 425
 426         clr.af = af;
 427         clr.dev = dev;
 428         clr.type = type;
 429         switch (type) {
 430         case RTM_GETADDR:
 431                 clr.size = sizeof(struct rtgenmsg);
 432                 break;
 433         case RTM_GETROUTE:
 434                 clr.size = sizeof(struct rtmsg);
 435                 break;
 436         default:
 437                 return;
 438         }
 439
 440         if (!cb)
 441                 return;
 442
 443         clr.msg = nlmsg_alloc_simple(type, flags);
 444         if (!clr.msg)
 445                 goto out;
 446
 447         nlmsg_append(clr.msg, &rtm, clr.size, 0);
 448         nl_cb_set(cb, NL_CB_VALID, NL_CB_CUSTOM, cb_clear_event, &clr);
 449         nl_cb_set(cb, NL_CB_FINISH, NL_CB_CUSTOM, cb_finish_event, &pending);
 450         nl_cb_err(cb, NL_CB_CUSTOM, error_handler, &pending);
 451
 452         nl_send_auto_complete(sock_rtnl, clr.msg);
 453         while (pending > 0)
 454                 nl_recvmsgs(sock_rtnl, cb);
 455
 456         nlmsg_free(clr.msg);
 457 out:
 458         nl_cb_put(cb);
 459 }
 460
 461 /*
 462  * Clear bridge (membership) state and bring down device
 463  */
 464 void system_if_clear_state(struct device *dev)
 465 {
 466         static char buf[256];
 467         char *bridge;
 468
 469         if (dev->external)
 470                 return;
 471
 472         dev->ifindex = system_if_resolve(dev);
 473         if (!dev->ifindex)
 474                 return;
 475
 476         system_if_flags(dev->ifname, 0, IFF_UP);
 477
 478         if (system_is_bridge(dev->ifname, buf, sizeof(buf))) {
 479                 D(SYSTEM, "Delete existing bridge named '%s'\n", dev->ifname);
 480                 system_bridge_delbr(dev);
 481                 return;
 482         }
 483
 484         bridge = system_get_bridge(dev->ifname, buf, sizeof(buf));
 485         if (bridge) {
 486                 D(SYSTEM, "Remove device '%s' from bridge '%s'\n", dev->ifname, bridge);
 487                 system_bridge_if(bridge, dev, SIOCBRDELIF, NULL);
 488         }
 489
 490         system_if_clear_entries(dev, RTM_GETROUTE, AF_INET);
 491         system_if_clear_entries(dev, RTM_GETADDR, AF_INET);
 492         system_if_clear_entries(dev, RTM_GETROUTE, AF_INET6);
 493         system_if_clear_entries(dev, RTM_GETADDR, AF_INET6);
 494         system_set_disable_ipv6(dev, "0");
 495 }
 496
 497 static inline unsigned long
 498 sec_to_jiffies(int val)
 499 {
 500         return (unsigned long) val * 100;
 501 }
 502
 503 int system_bridge_addbr(struct device *bridge, struct bridge_config *cfg)
 504 {
 505         unsigned long args[4] = {};
 506
 507         if (ioctl(sock_ioctl, SIOCBRADDBR, bridge->ifname) < 0)
 508                 return -1;
 509
 510         args[0] = BRCTL_SET_BRIDGE_STP_STATE;
 511         args[1] = !!cfg->stp;
 512         system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
 513
 514         args[0] = BRCTL_SET_BRIDGE_FORWARD_DELAY;
 515         args[1] = sec_to_jiffies(cfg->forward_delay);
 516         system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
 517
 518         system_set_dev_sysctl("/sys/devices/virtual/net/%s/bridge/multicast_snooping",
 519                 bridge->ifname, cfg->igmp_snoop ? "1" : "0");
 520
 521         if (cfg->flags & BRIDGE_OPT_AGEING_TIME) {
 522                 args[0] = BRCTL_SET_AGEING_TIME;
 523                 args[1] = sec_to_jiffies(cfg->ageing_time);
 524                 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
 525         }
 526
 527         if (cfg->flags & BRIDGE_OPT_HELLO_TIME) {
 528                 args[0] = BRCTL_SET_BRIDGE_HELLO_TIME;
 529                 args[1] = sec_to_jiffies(cfg->hello_time);
 530                 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
 531         }
 532
 533         if (cfg->flags & BRIDGE_OPT_MAX_AGE) {
 534                 args[0] = BRCTL_SET_BRIDGE_MAX_AGE;
 535                 args[1] = sec_to_jiffies(cfg->max_age);
 536                 system_bridge_if(bridge->ifname, NULL, SIOCDEVPRIVATE, &args);
 537         }
 538
 539         return 0;
 540 }
 541
 542 static int system_vlan(struct device *dev, int id)
 543 {
 544         struct vlan_ioctl_args ifr = {
 545                 .cmd = SET_VLAN_NAME_TYPE_CMD,
 546                 .u.name_type = VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD,
 547         };
 548
 549         ioctl(sock_ioctl, SIOCSIFVLAN, &ifr);
 550
 551         if (id < 0) {
 552                 ifr.cmd = DEL_VLAN_CMD;
 553                 ifr.u.VID = 0;
 554         } else {
 555                 ifr.cmd = ADD_VLAN_CMD;
 556                 ifr.u.VID = id;
 557         }
 558         strncpy(ifr.device1, dev->ifname, sizeof(ifr.device1));
 559         return ioctl(sock_ioctl, SIOCSIFVLAN, &ifr);
 560 }
 561
 562 int system_vlan_add(struct device *dev, int id)
 563 {
 564         return system_vlan(dev, id);
 565 }
 566
 567 int system_vlan_del(struct device *dev)
 568 {
 569         return system_vlan(dev, -1);
 570 }
 571
 572 static void
 573 system_if_get_settings(struct device *dev, struct device_settings *s)
 574 {
 575         struct ifreq ifr;
 576
 577         memset(&ifr, 0, sizeof(ifr));
 578         strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
 579
 580         if (ioctl(sock_ioctl, SIOCGIFMTU, &ifr) == 0) {
 581                 s->mtu = ifr.ifr_mtu;
 582                 s->flags |= DEV_OPT_MTU;
 583         }
 584
 585         if (ioctl(sock_ioctl, SIOCGIFTXQLEN, &ifr) == 0) {
 586                 s->txqueuelen = ifr.ifr_qlen;
 587                 s->flags |= DEV_OPT_TXQUEUELEN;
 588         }
 589
 590         if (ioctl(sock_ioctl, SIOCGIFHWADDR, &ifr) == 0) {
 591                 memcpy(s->macaddr, &ifr.ifr_hwaddr, sizeof(s->macaddr));
 592                 s->flags |= DEV_OPT_MACADDR;
 593         }
 594 }
 595
 596 static void
 597 system_if_apply_settings(struct device *dev, struct device_settings *s)
 598 {
 599         struct ifreq ifr;
 600
 601         memset(&ifr, 0, sizeof(ifr));
 602         strncpy(ifr.ifr_name, dev->ifname, sizeof(ifr.ifr_name));
 603         if (s->flags & DEV_OPT_MTU) {
 604                 ifr.ifr_mtu = s->mtu;
 605                 if (ioctl(sock_ioctl, SIOCSIFMTU, &ifr) < 0)
 606                         s->flags &= ~DEV_OPT_MTU;
 607         }
 608         if (s->flags & DEV_OPT_TXQUEUELEN) {
 609                 ifr.ifr_qlen = s->txqueuelen;
 610                 if (ioctl(sock_ioctl, SIOCSIFTXQLEN, &ifr) < 0)
 611                         s->flags &= ~DEV_OPT_TXQUEUELEN;
 612         }
 613         if (s->flags & DEV_OPT_MACADDR) {
 614                 memcpy(&ifr.ifr_hwaddr, s->macaddr, sizeof(s->macaddr));
 615                 if (ioctl(sock_ioctl, SIOCSIFHWADDR, &ifr) < 0)
 616                         s->flags &= ~DEV_OPT_MACADDR;
 617         }
 618 }
 619
 620 int system_if_up(struct device *dev)
 621 {
 622         system_if_get_settings(dev, &dev->orig_settings);
 623         system_if_apply_settings(dev, &dev->settings);
 624         dev->ifindex = system_if_resolve(dev);
 625         return system_if_flags(dev->ifname, IFF_UP, 0);
 626 }
 627
 628 int system_if_down(struct device *dev)
 629 {
 630         int ret = system_if_flags(dev->ifname, 0, IFF_UP);
 631         system_if_apply_settings(dev, &dev->orig_settings);
 632         return ret;
 633 }
 634
 635 int system_if_check(struct device *dev)
 636 {
 637         device_set_present(dev, (system_if_resolve(dev) > 0));
 638         return 0;
 639 }
 640
 641 struct device *
 642 system_if_get_parent(struct device *dev)
 643 {
 644         char buf[64], *devname;
 645         int ifindex, iflink, len;
 646         FILE *f;
 647
 648         snprintf(buf, sizeof(buf), "/sys/class/net/%s/iflink", dev->ifname);
 649         f = fopen(buf, "r");
 650         if (!f)
 651                 return NULL;
 652
 653         len = fread(buf, 1, sizeof(buf) - 1, f);
 654         fclose(f);
 655
 656         if (len <= 0)
 657                 return NULL;
 658
 659         buf[len] = 0;
 660         iflink = strtoul(buf, NULL, 0);
 661         ifindex = system_if_resolve(dev);
 662         if (!iflink || iflink == ifindex)
 663                 return NULL;
 664
 665         devname = if_indextoname(iflink, buf);
 666         if (!devname)
 667                 return NULL;
 668
 669         return device_get(devname, true);
 670 }
 671
 672 static bool
 673 read_string_file(int dir_fd, const char *file, char *buf, int len)
 674 {
 675         bool ret = false;
 676         char *c;
 677         int fd;
 678
 679         fd = openat(dir_fd, file, O_RDONLY);
 680         if (fd < 0)
 681                 return false;
 682
 683 retry:
 684         len = read(fd, buf, len - 1);
 685         if (len < 0) {
 686                 if (errno == EINTR)
 687                         goto retry;
 688         } else if (len > 0) {
 689                         buf[len] = 0;
 690
 691                         c = strchr(buf, '\n');
 692                         if (c)
 693                                 *c = 0;
 694
 695                         ret = true;
 696         }
 697
 698         close(fd);
 699
 700         return ret;
 701 }
 702
 703 static bool
 704 read_int_file(int dir_fd, const char *file, int *val)
 705 {
 706         char buf[64];
 707         bool ret = false;
 708
 709         ret = read_string_file(dir_fd, file, buf, sizeof(buf));
 710         if (ret)
 711                 *val = strtoul(buf, NULL, 0);
 712
 713         return ret;
 714 }
 715
 716 /* Assume advertised flags == supported flags */
 717 static const struct {
 718         uint32_t mask;
 719         const char *name;
 720 } ethtool_link_modes[] = {
 721         { ADVERTISED_10baseT_Half, "10H" },
 722         { ADVERTISED_10baseT_Full, "10F" },
 723         { ADVERTISED_100baseT_Half, "100H" },
 724         { ADVERTISED_100baseT_Full, "100F" },
 725         { ADVERTISED_1000baseT_Half, "1000H" },
 726         { ADVERTISED_1000baseT_Full, "1000F" },
 727 };
 728
 729 static void system_add_link_modes(struct blob_buf *b, __u32 mask)
 730 {
 731         int i;
 732         for (i = 0; i < ARRAY_SIZE(ethtool_link_modes); i++) {
 733                 if (mask & ethtool_link_modes[i].mask)
 734                         blobmsg_add_string(b, NULL, ethtool_link_modes[i].name);
 735         }
 736 }
 737
 738 int
 739 system_if_dump_info(struct device *dev, struct blob_buf *b)
 740 {
 741         struct ethtool_cmd ecmd;
 742         struct ifreq ifr;
 743         char buf[64], *s;
 744         void *c;
 745         int dir_fd, val = 0;
 746
 747         snprintf(buf, sizeof(buf), "/sys/class/net/%s", dev->ifname);
 748         dir_fd = open(buf, O_DIRECTORY);
 749
 750         if (read_int_file(dir_fd, "carrier", &val))
 751                 blobmsg_add_u8(b, "link", !!val);
 752
 753         memset(&ecmd, 0, sizeof(ecmd));
 754         memset(&ifr, 0, sizeof(ifr));
 755         strcpy(ifr.ifr_name, dev->ifname);
 756         ifr.ifr_data = (caddr_t) &ecmd;
 757         ecmd.cmd = ETHTOOL_GSET;
 758
 759         if (ioctl(sock_ioctl, SIOCETHTOOL, &ifr) == 0) {
 760                 c = blobmsg_open_array(b, "link-advertising");
 761                 system_add_link_modes(b, ecmd.advertising);
 762                 blobmsg_close_array(b, c);
 763
 764                 c = blobmsg_open_array(b, "link-supported");
 765                 system_add_link_modes(b, ecmd.supported);
 766                 blobmsg_close_array(b, c);
 767
 768                 s = blobmsg_alloc_string_buffer(b, "speed", 8);
 769                 snprintf(s, 8, "%d%c", ethtool_cmd_speed(&ecmd),
 770                         ecmd.duplex == DUPLEX_HALF ? 'H' : 'F');
 771                 blobmsg_add_string_buffer(b);
 772         }
 773
 774         close(dir_fd);
 775         return 0;
 776 }
 777
 778 int
 779 system_if_dump_stats(struct device *dev, struct blob_buf *b)
 780 {
 781         const char *const counters[] = {
 782                 "collisions",     "rx_frame_errors",   "tx_compressed",
 783                 "multicast",      "rx_length_errors",  "tx_dropped",
 784                 "rx_bytes",       "rx_missed_errors",  "tx_errors",
 785                 "rx_compressed",  "rx_over_errors",    "tx_fifo_errors",
 786                 "rx_crc_errors",  "rx_packets",        "tx_heartbeat_errors",
 787                 "rx_dropped",     "tx_aborted_errors", "tx_packets",
 788                 "rx_errors",      "tx_bytes",          "tx_window_errors",
 789                 "rx_fifo_errors", "tx_carrier_errors",
 790         };
 791         char buf[64];
 792         int stats_dir;
 793         int i, val = 0;
 794
 795         snprintf(buf, sizeof(buf), "/sys/class/net/%s/statistics", dev->ifname);
 796         stats_dir = open(buf, O_DIRECTORY);
 797         if (stats_dir < 0)
 798                 return -1;
 799
 800         for (i = 0; i < ARRAY_SIZE(counters); i++)
 801                 if (read_int_file(stats_dir, counters[i], &val))
 802                         blobmsg_add_u32(b, counters[i], val);
 803
 804         close(stats_dir);
 805         return 0;
 806 }
 807
 808 static int system_addr(struct device *dev, struct device_addr *addr, int cmd)
 809 {
 810         int alen = ((addr->flags & DEVADDR_FAMILY) == DEVADDR_INET4) ? 4 : 16;
 811         struct ifaddrmsg ifa = {
 812                 .ifa_family = (alen == 4) ? AF_INET : AF_INET6,
 813                 .ifa_prefixlen = addr->mask,
 814                 .ifa_index = dev->ifindex,
 815         };
 816
 817         struct nl_msg *msg;
 818
 819         dev = addr->device;
 820         if (dev) {
 821                 if (!dev->ifindex)
 822                         return -1;
 823
 824                 ifa.ifa_index = dev->ifindex;
 825         }
 826
 827         msg = nlmsg_alloc_simple(cmd, 0);
 828         if (!msg)
 829                 return -1;
 830
 831         nlmsg_append(msg, &ifa, sizeof(ifa), 0);
 832         nla_put(msg, IFA_LOCAL, alen, &addr->addr);
 833         return system_rtnl_call(msg);
 834 }
 835
 836 int system_add_address(struct device *dev, struct device_addr *addr)
 837 {
 838         return system_addr(dev, addr, RTM_NEWADDR);
 839 }
 840
 841 int system_del_address(struct device *dev, struct device_addr *addr)
 842 {
 843         return system_addr(dev, addr, RTM_DELADDR);
 844 }
 845
 846 static int system_rt(struct device *dev, struct device_route *route, int cmd)
 847 {
 848         int alen = ((route->flags & DEVADDR_FAMILY) == DEVADDR_INET4) ? 4 : 16;
 849         bool have_gw;
 850         unsigned int flags = 0;
 851         int ifindex = dev->ifindex;
 852
 853         if (alen == 4)
 854                 have_gw = !!route->nexthop.in.s_addr;
 855         else
 856                 have_gw = route->nexthop.in6.s6_addr32[0] ||
 857                         route->nexthop.in6.s6_addr32[1] ||
 858                         route->nexthop.in6.s6_addr32[2] ||
 859                         route->nexthop.in6.s6_addr32[3];
 860
 861         unsigned char scope = (cmd == RTM_DELROUTE) ? RT_SCOPE_NOWHERE :
 862                         (have_gw) ? RT_SCOPE_UNIVERSE : RT_SCOPE_LINK;
 863
 864         struct rtmsg rtm = {
 865                 .rtm_family = (alen == 4) ? AF_INET : AF_INET6,
 866                 .rtm_dst_len = route->mask,
 867                 .rtm_table = RT_TABLE_MAIN,
 868                 .rtm_protocol = RTPROT_BOOT,
 869                 .rtm_scope = scope,
 870                 .rtm_type = (cmd == RTM_DELROUTE) ? 0: RTN_UNICAST,
 871         };
 872         struct nl_msg *msg;
 873
 874         if (cmd == RTM_NEWROUTE)
 875                 flags |= NLM_F_CREATE | NLM_F_REPLACE;
 876
 877         dev = route->device;
 878         if (dev) {
 879                 if (!dev->ifindex)
 880                         return -1;
 881
 882                 ifindex = dev->ifindex;
 883         }
 884
 885         msg = nlmsg_alloc_simple(cmd, flags);
 886         if (!msg)
 887                 return -1;
 888
 889         nlmsg_append(msg, &rtm, sizeof(rtm), 0);
 890
 891         if (route->mask)
 892                 nla_put(msg, RTA_DST, alen, &route->addr);
 893
 894         if (have_gw)
 895                 nla_put(msg, RTA_GATEWAY, alen, &route->nexthop);
 896
 897         if (route->flags & DEVADDR_DEVICE)
 898                 nla_put_u32(msg, RTA_OIF, ifindex);
 899
 900         return system_rtnl_call(msg);
 901 }
 902
 903 int system_add_route(struct device *dev, struct device_route *route)
 904 {
 905         return system_rt(dev, route, RTM_NEWROUTE);
 906 }
 907
 908 int system_del_route(struct device *dev, struct device_route *route)
 909 {
 910         return system_rt(dev, route, RTM_DELROUTE);
 911 }
 912
 913 int system_flush_routes(void)
 914 {
 915         const char *names[] = {
 916                 "/proc/sys/net/ipv4/route/flush",
 917                 "/proc/sys/net/ipv6/route/flush"
 918         };
 919         int fd, i;
 920
 921         for (i = 0; i < ARRAY_SIZE(names); i++) {
 922                 fd = open(names[i], O_WRONLY);
 923                 if (fd < 0)
 924                         continue;
 925
 926                 write(fd, "-1", 2);
 927                 close(fd);
 928         }
 929         return 0;
 930 }
 931
 932 time_t system_get_rtime(void)
 933 {
 934         struct timespec ts;
 935         struct timeval tv;
 936
 937         if (syscall(__NR_clock_gettime, CLOCK_MONOTONIC, &ts) == 0)
 938                 return ts.tv_sec;
 939
 940         if (gettimeofday(&tv, NULL) == 0)
 941                 return tv.tv_sec;
 942
 943         return 0;
 944 }