interface-ip.c

   1 #include <string.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4 #include <unistd.h>
   5
   6 #include <arpa/inet.h>
   7
   8 #include "netifd.h"
   9 #include "device.h"
  10 #include "interface.h"
  11 #include "interface-ip.h"
  12 #include "proto.h"
  13 #include "ubus.h"
  14 #include "system.h"
  15
  16 enum {
  17         ROUTE_INTERFACE,
  18         ROUTE_TARGET,
  19         ROUTE_MASK,
  20         ROUTE_GATEWAY,
  21         ROUTE_METRIC,
  22         ROUTE_MTU,
  23         __ROUTE_MAX
  24 };
  25
  26 static const struct blobmsg_policy route_attr[__ROUTE_MAX] = {
  27         [ROUTE_INTERFACE] = { .name = "interface", .type = BLOBMSG_TYPE_STRING },
  28         [ROUTE_TARGET] = { .name = "target", .type = BLOBMSG_TYPE_STRING },
  29         [ROUTE_MASK] = { .name = "netmask", .type = BLOBMSG_TYPE_STRING },
  30         [ROUTE_GATEWAY] = { .name = "gateway", .type = BLOBMSG_TYPE_STRING },
  31         [ROUTE_METRIC] = { .name = "metric", .type = BLOBMSG_TYPE_INT32 },
  32         [ROUTE_MTU] = { .name = "mtu", .type = BLOBMSG_TYPE_INT32 },
  33 };
  34
  35 const struct config_param_list route_attr_list = {
  36         .n_params = __ROUTE_MAX,
  37         .params = route_attr,
  38 };
  39
  40 static bool
  41 match_if_addr(union if_addr *a1, union if_addr *a2, int mask)
  42 {
  43         uint8_t *p1, *p2;
  44         int m_bytes = (mask + 7) / 8;
  45         uint8_t m_clear = (1 << (m_bytes * 8 - mask)) - 1;
  46
  47         p1 = alloca(m_bytes);
  48         p2 = alloca(m_bytes);
  49
  50         memcpy(p1, a1, m_bytes);
  51         memcpy(p2, a2, m_bytes);
  52
  53         p1[m_bytes - 1] &= ~m_clear;
  54         p2[m_bytes - 1] &= ~m_clear;
  55
  56         return !memcmp(p1, p2, m_bytes);
  57 }
  58
  59 static bool
  60 __find_ip_addr_target(struct interface_ip_settings *ip, union if_addr *a, bool v6)
  61 {
  62         struct device_addr *addr;
  63
  64         vlist_for_each_element(&ip->addr, addr, node) {
  65                 if (!addr->enabled)
  66                         continue;
  67
  68                 if (v6 != ((addr->flags & DEVADDR_FAMILY) == DEVADDR_INET6))
  69                         continue;
  70
  71                 if (!match_if_addr(&addr->addr, a, addr->mask))
  72                         continue;
  73
  74                 return true;
  75         }
  76
  77         return false;
  78 }
  79
  80 static void
  81 __find_ip_route_target(struct interface_ip_settings *ip, union if_addr *a,
  82                        bool v6, struct device_route **res)
  83 {
  84         struct device_route *route;
  85
  86         vlist_for_each_element(&ip->route, route, node) {
  87                 if (!route->enabled)
  88                         continue;
  89
  90                 if (v6 != ((route->flags & DEVADDR_FAMILY) == DEVADDR_INET6))
  91                         continue;
  92
  93                 if (!match_if_addr(&route->addr, a, route->mask))
  94                         continue;
  95
  96                 if (!*res || route->mask < (*res)->mask)
  97                         *res = route;
  98         }
  99 }
 100
 101 static bool
 102 interface_ip_find_addr_target(struct interface *iface, union if_addr *a, bool v6)
 103 {
 104         return __find_ip_addr_target(&iface->proto_ip, a, v6) ||
 105                __find_ip_addr_target(&iface->config_ip, a, v6);
 106 }
 107
 108 static void
 109 interface_ip_find_route_target(struct interface *iface, union if_addr *a,
 110                                bool v6, struct device_route **route)
 111 {
 112         __find_ip_route_target(&iface->proto_ip, a, v6, route);
 113         __find_ip_route_target(&iface->config_ip, a, v6, route);
 114 }
 115
 116 struct interface *
 117 interface_ip_add_target_route(union if_addr *addr, bool v6)
 118 {
 119         struct interface *iface;
 120         struct device_route *route, *r_next = NULL;
 121
 122         route = calloc(1, sizeof(*route));
 123         if (!route)
 124                 return false;
 125
 126         route->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4;
 127         route->mask = v6 ? 128 : 32;
 128         memcpy(&route->addr, addr, v6 ? sizeof(addr->in6) : sizeof(addr->in));
 129
 130         vlist_for_each_element(&interfaces, iface, node) {
 131                 /* look for locally addressable target first */
 132                 if (interface_ip_find_addr_target(iface, addr, v6))
 133                         goto done;
 134
 135                 /* do not stop at the first route, let the lookup compare
 136                  * masks to find the best match */
 137                 interface_ip_find_route_target(iface, addr, v6, &r_next);
 138         }
 139
 140         if (!r_next)
 141                 return NULL;
 142
 143         iface = r_next->iface;
 144         memcpy(&route->nexthop, &r_next->nexthop, sizeof(route->nexthop));
 145         route->mtu = r_next->mtu;
 146         route->metric = r_next->metric;
 147
 148 done:
 149         route->iface = iface;
 150         vlist_add(&iface->host_routes, &route->node, &route->flags);
 151         return iface;
 152 }
 153
 154 void
 155 interface_ip_add_route(struct interface *iface, struct blob_attr *attr, bool v6)
 156 {
 157         struct interface_ip_settings *ip;
 158         struct blob_attr *tb[__ROUTE_MAX], *cur;
 159         struct device_route *route;
 160         int af = v6 ? AF_INET6 : AF_INET;
 161
 162         blobmsg_parse(route_attr, __ROUTE_MAX, tb, blobmsg_data(attr), blobmsg_data_len(attr));
 163
 164         if (!iface) {
 165                 if ((cur = tb[ROUTE_INTERFACE]) == NULL)
 166                         return;
 167
 168                 iface = vlist_find(&interfaces, blobmsg_data(cur), iface, node);
 169                 if (!iface)
 170                         return;
 171
 172                 ip = &iface->config_ip;
 173         } else {
 174                 ip = &iface->proto_ip;
 175         }
 176
 177         route = calloc(1, sizeof(*route));
 178         if (!route)
 179                 return;
 180
 181         route->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4;
 182         route->mask = v6 ? 128 : 32;
 183         if ((cur = tb[ROUTE_MASK]) != NULL) {
 184                 route->mask = parse_netmask_string(blobmsg_data(cur), v6);
 185                 if (route->mask > (v6 ? 128 : 32))
 186                         goto error;
 187         }
 188
 189         if ((cur = tb[ROUTE_TARGET]) != NULL) {
 190                 if (!inet_pton(af, blobmsg_data(cur), &route->addr)) {
 191                         DPRINTF("Failed to parse route target: %s\n", (char *) blobmsg_data(cur));
 192                         goto error;
 193                 }
 194         }
 195
 196         if ((cur = tb[ROUTE_GATEWAY]) != NULL) {
 197                 if (!inet_pton(af, blobmsg_data(cur), &route->nexthop)) {
 198                         DPRINTF("Failed to parse route gateway: %s\n", (char *) blobmsg_data(cur));
 199                         goto error;
 200                 }
 201         }
 202
 203         if ((cur = tb[ROUTE_METRIC]) != NULL) {
 204                 route->metric = blobmsg_get_u32(cur);
 205                 route->flags |= DEVROUTE_METRIC;
 206         }
 207
 208         if ((cur = tb[ROUTE_MTU]) != NULL)
 209                 route->mtu = blobmsg_get_u32(cur);
 210
 211         vlist_add(&ip->route, &route->node, &route->flags);
 212         return;
 213
 214 error:
 215         free(route);
 216 }
 217
 218 static int
 219 addr_cmp(const void *k1, const void *k2, void *ptr)
 220 {
 221         return memcmp(k1, k2, sizeof(struct device_addr) -
 222                       offsetof(struct device_addr, flags));
 223 }
 224
 225 static int
 226 route_cmp(const void *k1, const void *k2, void *ptr)
 227 {
 228         return memcmp(k1, k2, sizeof(struct device_route) -
 229                       offsetof(struct device_route, flags));
 230 }
 231
 232 static void
 233 interface_update_proto_addr(struct vlist_tree *tree,
 234                             struct vlist_node *node_new,
 235                             struct vlist_node *node_old)
 236 {
 237         struct interface_ip_settings *ip;
 238         struct interface *iface;
 239         struct device *dev;
 240         struct device_addr *a_new = NULL, *a_old = NULL;
 241         bool keep = false;
 242
 243         ip = container_of(tree, struct interface_ip_settings, addr);
 244         iface = ip->iface;
 245         dev = iface->l3_dev.dev;
 246
 247         if (node_new) {
 248                 a_new = container_of(node_new, struct device_addr, node);
 249
 250                 if ((a_new->flags & DEVADDR_FAMILY) == DEVADDR_INET4 &&
 251                     !a_new->broadcast) {
 252
 253                         uint32_t mask = ~0;
 254                         uint32_t *a = (uint32_t *) &a_new->addr;
 255
 256                         mask >>= a_new->mask;
 257                         a_new->broadcast = *a | mask;
 258                 }
 259         }
 260
 261         if (node_old)
 262                 a_old = container_of(node_old, struct device_addr, node);
 263
 264         if (a_new && a_old) {
 265                 keep = true;
 266
 267                 if (a_old->flags != a_new->flags)
 268                         keep = false;
 269
 270                 if ((a_new->flags & DEVADDR_FAMILY) == DEVADDR_INET4 &&
 271                     a_new->broadcast != a_old->broadcast)
 272                         keep = false;
 273         }
 274
 275         if (node_old) {
 276                 if (!(a_old->flags & DEVADDR_EXTERNAL) && a_old->enabled && !keep)
 277                         system_del_address(dev, a_old);
 278                 free(a_old);
 279         }
 280
 281         if (node_new) {
 282                 if (!(a_new->flags & DEVADDR_EXTERNAL) && !keep)
 283                         system_add_address(dev, a_new);
 284                 a_new->enabled = true;
 285         }
 286 }
 287
 288 static bool
 289 enable_route(struct interface_ip_settings *ip, struct device_route *route)
 290 {
 291         if (ip->no_defaultroute && !route->mask)
 292                 return false;
 293
 294         return ip->enabled;
 295 }
 296
 297 static void
 298 interface_update_proto_route(struct vlist_tree *tree,
 299                              struct vlist_node *node_new,
 300                              struct vlist_node *node_old)
 301 {
 302         struct interface_ip_settings *ip;
 303         struct interface *iface;
 304         struct device *dev;
 305         struct device_route *route_old, *route_new;
 306         bool keep = false;
 307
 308         ip = container_of(tree, struct interface_ip_settings, route);
 309         iface = ip->iface;
 310         dev = iface->l3_dev.dev;
 311
 312         route_old = container_of(node_old, struct device_route, node);
 313         route_new = container_of(node_new, struct device_route, node);
 314
 315         if (node_old && node_new)
 316                 keep = !memcmp(&route_old->nexthop, &route_new->nexthop, sizeof(route_old->nexthop));
 317
 318         if (node_old) {
 319                 if (!(route_old->flags & DEVADDR_EXTERNAL) && route_old->enabled && !keep)
 320                         system_del_route(dev, route_old);
 321                 free(route_old);
 322         }
 323
 324         if (node_new) {
 325                 bool _enabled = enable_route(ip, route_new);
 326
 327                 if (!(route_new->flags & DEVADDR_EXTERNAL) && !keep && _enabled)
 328                         system_add_route(dev, route_new);
 329
 330                 route_new->iface = iface;
 331                 route_new->enabled = _enabled;
 332         }
 333 }
 334
 335 static void
 336 interface_update_host_route(struct vlist_tree *tree,
 337                              struct vlist_node *node_new,
 338                              struct vlist_node *node_old)
 339 {
 340         struct interface *iface;
 341         struct device *dev;
 342         struct device_route *route_old, *route_new;
 343
 344         iface = container_of(tree, struct interface, host_routes);
 345         dev = iface->l3_dev.dev;
 346
 347         route_old = container_of(node_old, struct device_route, node);
 348         route_new = container_of(node_new, struct device_route, node);
 349
 350         if (node_old) {
 351                 system_del_route(dev, route_old);
 352                 free(route_old);
 353         }
 354
 355         if (node_new)
 356                 system_add_route(dev, route_new);
 357 }
 358
 359 void
 360 interface_add_dns_server(struct interface_ip_settings *ip, const char *str)
 361 {
 362         struct dns_server *s;
 363
 364         s = calloc(1, sizeof(*s));
 365         s->af = AF_INET;
 366         if (inet_pton(s->af, str, &s->addr.in))
 367                 goto add;
 368
 369         s->af = AF_INET6;
 370         if (inet_pton(s->af, str, &s->addr.in))
 371                 goto add;
 372
 373         free(s);
 374         return;
 375
 376 add:
 377         D(INTERFACE, "Add IPv%c DNS server: %s\n",
 378           s->af == AF_INET6 ? '6' : '4', str);
 379         vlist_simple_add(&ip->dns_servers, &s->node);
 380 }
 381
 382 void
 383 interface_add_dns_server_list(struct interface_ip_settings *ip, struct blob_attr *list)
 384 {
 385         struct blob_attr *cur;
 386         int rem;
 387
 388         blobmsg_for_each_attr(cur, list, rem) {
 389                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 390                         continue;
 391
 392                 if (!blobmsg_check_attr(cur, NULL))
 393                         continue;
 394
 395                 interface_add_dns_server(ip, blobmsg_data(cur));
 396         }
 397 }
 398
 399 static void
 400 interface_add_dns_search_domain(struct interface_ip_settings *ip, const char *str)
 401 {
 402         struct dns_search_domain *s;
 403         int len = strlen(str);
 404
 405         s = calloc(1, sizeof(*s) + len + 1);
 406         if (!s)
 407                 return;
 408
 409         D(INTERFACE, "Add DNS search domain: %s\n", str);
 410         memcpy(s->name, str, len);
 411         vlist_simple_add(&ip->dns_search, &s->node);
 412 }
 413
 414 void
 415 interface_add_dns_search_list(struct interface_ip_settings *ip, struct blob_attr *list)
 416 {
 417         struct blob_attr *cur;
 418         int rem;
 419
 420         blobmsg_for_each_attr(cur, list, rem) {
 421                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 422                         continue;
 423
 424                 if (!blobmsg_check_attr(cur, NULL))
 425                         continue;
 426
 427                 interface_add_dns_search_domain(ip, blobmsg_data(cur));
 428         }
 429 }
 430
 431 static void
 432 write_resolv_conf_entries(FILE *f, struct interface_ip_settings *ip)
 433 {
 434         struct dns_server *s;
 435         struct dns_search_domain *d;
 436         const char *str;
 437         char buf[32];
 438
 439         vlist_simple_for_each_element(&ip->dns_servers, s, node) {
 440                 str = inet_ntop(s->af, &s->addr, buf, sizeof(buf));
 441                 if (!str)
 442                         continue;
 443
 444                 fprintf(f, "nameserver %s\n", str);
 445         }
 446
 447         vlist_simple_for_each_element(&ip->dns_search, d, node) {
 448                 fprintf(f, "search %s\n", d->name);
 449         }
 450 }
 451
 452 void
 453 interface_write_resolv_conf(void)
 454 {
 455         struct interface *iface;
 456         char *path = alloca(strlen(resolv_conf) + 5);
 457         FILE *f;
 458
 459         sprintf(path, "%s.tmp", resolv_conf);
 460         unlink(path);
 461         f = fopen(path, "w");
 462         if (!f) {
 463                 D(INTERFACE, "Failed to open %s for writing\n", path);
 464                 return;
 465         }
 466
 467         vlist_for_each_element(&interfaces, iface, node) {
 468                 if (iface->state != IFS_UP)
 469                         continue;
 470
 471                 if (vlist_simple_empty(&iface->proto_ip.dns_search) &&
 472                     vlist_simple_empty(&iface->proto_ip.dns_servers) &&
 473                         vlist_simple_empty(&iface->config_ip.dns_search) &&
 474                     vlist_simple_empty(&iface->config_ip.dns_servers))
 475                         continue;
 476
 477                 fprintf(f, "# Interface %s\n", iface->name);
 478                 write_resolv_conf_entries(f, &iface->config_ip);
 479                 write_resolv_conf_entries(f, &iface->proto_ip);
 480         }
 481         fclose(f);
 482         if (rename(path, resolv_conf) < 0) {
 483                 D(INTERFACE, "Failed to replace %s\n", resolv_conf);
 484                 unlink(path);
 485         }
 486 }
 487
 488 void interface_ip_set_enabled(struct interface_ip_settings *ip, bool enabled)
 489 {
 490         struct device_addr *addr;
 491         struct device_route *route;
 492         struct device *dev;
 493
 494         ip->enabled = enabled;
 495         dev = ip->iface->l3_dev.dev;
 496         if (!dev)
 497                 return;
 498
 499         vlist_for_each_element(&ip->addr, addr, node) {
 500                 if (addr->enabled == enabled)
 501                         continue;
 502
 503                 if (enabled)
 504                         system_add_address(dev, addr);
 505                 else
 506                         system_del_address(dev, addr);
 507                 addr->enabled = enabled;
 508         }
 509
 510         vlist_for_each_element(&ip->route, route, node) {
 511                 bool _enabled = enabled;
 512
 513                 if (!enable_route(ip, route))
 514                         _enabled = false;
 515
 516                 if (route->enabled == _enabled)
 517                         continue;
 518
 519                 if (_enabled) {
 520                         if (!(route->flags & DEVROUTE_METRIC))
 521                                 route->metric = ip->iface->metric;
 522
 523                         system_add_route(dev, route);
 524                 } else
 525                         system_del_route(dev, route);
 526                 route->enabled = _enabled;
 527         }
 528 }
 529
 530 void
 531 interface_ip_update_start(struct interface_ip_settings *ip)
 532 {
 533         vlist_simple_update(&ip->dns_servers);
 534         vlist_simple_update(&ip->dns_search);
 535         vlist_update(&ip->route);
 536         vlist_update(&ip->addr);
 537 }
 538
 539 void
 540 interface_ip_update_complete(struct interface_ip_settings *ip)
 541 {
 542         vlist_simple_flush(&ip->dns_servers);
 543         vlist_simple_flush(&ip->dns_search);
 544         vlist_flush(&ip->route);
 545         vlist_flush(&ip->addr);
 546 }
 547
 548 void
 549 interface_ip_flush(struct interface_ip_settings *ip)
 550 {
 551         if (ip == &ip->iface->proto_ip)
 552                 vlist_flush_all(&ip->iface->host_routes);
 553         vlist_simple_flush_all(&ip->dns_servers);
 554         vlist_simple_flush_all(&ip->dns_search);
 555         vlist_flush_all(&ip->route);
 556         vlist_flush_all(&ip->addr);
 557 }
 558
 559 static void
 560 __interface_ip_init(struct interface_ip_settings *ip, struct interface *iface)
 561 {
 562         ip->iface = iface;
 563         ip->enabled = true;
 564         vlist_simple_init(&ip->dns_search, struct dns_search_domain, node);
 565         vlist_simple_init(&ip->dns_servers, struct dns_server, node);
 566         vlist_init(&ip->route, route_cmp, interface_update_proto_route);
 567         vlist_init(&ip->addr, addr_cmp, interface_update_proto_addr);
 568 }
 569
 570 void
 571 interface_ip_init(struct interface *iface)
 572 {
 573         __interface_ip_init(&iface->proto_ip, iface);
 574         __interface_ip_init(&iface->config_ip, iface);
 575         vlist_init(&iface->host_routes, route_cmp, interface_update_host_route);
 576 }