interface-ip.c

   1 /*
   2  * netifd - network interface daemon
   3  * Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License version 2
   7  * as published by the Free Software Foundation
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  */
  14 #include <string.h>
  15 #include <stdlib.h>
  16 #include <stdio.h>
  17 #include <unistd.h>
  18
  19 #include <arpa/inet.h>
  20
  21 #include "netifd.h"
  22 #include "device.h"
  23 #include "interface.h"
  24 #include "interface-ip.h"
  25 #include "proto.h"
  26 #include "ubus.h"
  27 #include "system.h"
  28
  29 enum {
  30         ROUTE_INTERFACE,
  31         ROUTE_TARGET,
  32         ROUTE_MASK,
  33         ROUTE_GATEWAY,
  34         ROUTE_METRIC,
  35         ROUTE_MTU,
  36         __ROUTE_MAX
  37 };
  38
  39 static const struct blobmsg_policy route_attr[__ROUTE_MAX] = {
  40         [ROUTE_INTERFACE] = { .name = "interface", .type = BLOBMSG_TYPE_STRING },
  41         [ROUTE_TARGET] = { .name = "target", .type = BLOBMSG_TYPE_STRING },
  42         [ROUTE_MASK] = { .name = "netmask", .type = BLOBMSG_TYPE_STRING },
  43         [ROUTE_GATEWAY] = { .name = "gateway", .type = BLOBMSG_TYPE_STRING },
  44         [ROUTE_METRIC] = { .name = "metric", .type = BLOBMSG_TYPE_INT32 },
  45         [ROUTE_MTU] = { .name = "mtu", .type = BLOBMSG_TYPE_INT32 },
  46 };
  47
  48 const struct config_param_list route_attr_list = {
  49         .n_params = __ROUTE_MAX,
  50         .params = route_attr,
  51 };
  52
  53 static void
  54 clear_if_addr(union if_addr *a, int mask)
  55 {
  56         int m_bytes = (mask + 7) / 8;
  57         uint8_t m_clear = (1 << (m_bytes * 8 - mask)) - 1;
  58         uint8_t *p = (uint8_t *) a;
  59
  60         if (m_bytes < sizeof(a))
  61                 memset(p + m_bytes, 0, sizeof(a) - m_bytes);
  62
  63         p[m_bytes - 1] &= ~m_clear;
  64 }
  65
  66 static bool
  67 match_if_addr(union if_addr *a1, union if_addr *a2, int mask)
  68 {
  69         union if_addr *p1, *p2;
  70
  71         p1 = alloca(sizeof(*a1));
  72         p2 = alloca(sizeof(*a2));
  73
  74         memcpy(p1, a1, sizeof(*a1));
  75         clear_if_addr(p1, mask);
  76         memcpy(p2, a2, sizeof(*a2));
  77         clear_if_addr(p2, mask);
  78
  79         return !memcmp(p1, p2, sizeof(*p1));
  80 }
  81
  82 static bool
  83 __find_ip_addr_target(struct interface_ip_settings *ip, union if_addr *a, bool v6)
  84 {
  85         struct device_addr *addr;
  86
  87         vlist_for_each_element(&ip->addr, addr, node) {
  88                 if (!addr->enabled)
  89                         continue;
  90
  91                 if (v6 != ((addr->flags & DEVADDR_FAMILY) == DEVADDR_INET6))
  92                         continue;
  93
  94                 if (!match_if_addr(&addr->addr, a, addr->mask))
  95                         continue;
  96
  97                 return true;
  98         }
  99
 100         return false;
 101 }
 102
 103 static void
 104 __find_ip_route_target(struct interface_ip_settings *ip, union if_addr *a,
 105                        bool v6, struct device_route **res)
 106 {
 107         struct device_route *route;
 108
 109         vlist_for_each_element(&ip->route, route, node) {
 110                 if (!route->enabled)
 111                         continue;
 112
 113                 if (v6 != ((route->flags & DEVADDR_FAMILY) == DEVADDR_INET6))
 114                         continue;
 115
 116                 if (!match_if_addr(&route->addr, a, route->mask))
 117                         continue;
 118
 119                 if (!*res || route->mask < (*res)->mask)
 120                         *res = route;
 121         }
 122 }
 123
 124 static bool
 125 interface_ip_find_addr_target(struct interface *iface, union if_addr *a, bool v6)
 126 {
 127         return __find_ip_addr_target(&iface->proto_ip, a, v6) ||
 128                __find_ip_addr_target(&iface->config_ip, a, v6);
 129 }
 130
 131 static void
 132 interface_ip_find_route_target(struct interface *iface, union if_addr *a,
 133                                bool v6, struct device_route **route)
 134 {
 135         __find_ip_route_target(&iface->proto_ip, a, v6, route);
 136         __find_ip_route_target(&iface->config_ip, a, v6, route);
 137 }
 138
 139 struct interface *
 140 interface_ip_add_target_route(union if_addr *addr, bool v6)
 141 {
 142         struct interface *iface;
 143         struct device_route *route, *r_next = NULL;
 144
 145         route = calloc(1, sizeof(*route));
 146         if (!route)
 147                 return false;
 148
 149         route->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4;
 150         route->mask = v6 ? 128 : 32;
 151         memcpy(&route->addr, addr, v6 ? sizeof(addr->in6) : sizeof(addr->in));
 152
 153         vlist_for_each_element(&interfaces, iface, node) {
 154                 /* look for locally addressable target first */
 155                 if (interface_ip_find_addr_target(iface, addr, v6))
 156                         goto done;
 157
 158                 /* do not stop at the first route, let the lookup compare
 159                  * masks to find the best match */
 160                 interface_ip_find_route_target(iface, addr, v6, &r_next);
 161         }
 162
 163         if (!r_next)
 164                 return NULL;
 165
 166         iface = r_next->iface;
 167         memcpy(&route->nexthop, &r_next->nexthop, sizeof(route->nexthop));
 168         route->mtu = r_next->mtu;
 169         route->metric = r_next->metric;
 170
 171 done:
 172         route->iface = iface;
 173         vlist_add(&iface->host_routes, &route->node, &route->flags);
 174         return iface;
 175 }
 176
 177 void
 178 interface_ip_add_route(struct interface *iface, struct blob_attr *attr, bool v6)
 179 {
 180         struct interface_ip_settings *ip;
 181         struct blob_attr *tb[__ROUTE_MAX], *cur;
 182         struct device_route *route;
 183         int af = v6 ? AF_INET6 : AF_INET;
 184
 185         blobmsg_parse(route_attr, __ROUTE_MAX, tb, blobmsg_data(attr), blobmsg_data_len(attr));
 186
 187         if (!iface) {
 188                 if ((cur = tb[ROUTE_INTERFACE]) == NULL)
 189                         return;
 190
 191                 iface = vlist_find(&interfaces, blobmsg_data(cur), iface, node);
 192                 if (!iface)
 193                         return;
 194
 195                 ip = &iface->config_ip;
 196         } else {
 197                 ip = &iface->proto_ip;
 198         }
 199
 200         route = calloc(1, sizeof(*route));
 201         if (!route)
 202                 return;
 203
 204         route->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4;
 205         route->mask = v6 ? 128 : 32;
 206         if ((cur = tb[ROUTE_MASK]) != NULL) {
 207                 route->mask = parse_netmask_string(blobmsg_data(cur), v6);
 208                 if (route->mask > (v6 ? 128 : 32))
 209                         goto error;
 210         }
 211
 212         if ((cur = tb[ROUTE_TARGET]) != NULL) {
 213                 if (!inet_pton(af, blobmsg_data(cur), &route->addr)) {
 214                         DPRINTF("Failed to parse route target: %s\n", (char *) blobmsg_data(cur));
 215                         goto error;
 216                 }
 217         }
 218
 219         if ((cur = tb[ROUTE_GATEWAY]) != NULL) {
 220                 if (!inet_pton(af, blobmsg_data(cur), &route->nexthop)) {
 221                         DPRINTF("Failed to parse route gateway: %s\n", (char *) blobmsg_data(cur));
 222                         goto error;
 223                 }
 224         }
 225
 226         if ((cur = tb[ROUTE_METRIC]) != NULL) {
 227                 route->metric = blobmsg_get_u32(cur);
 228                 route->flags |= DEVROUTE_METRIC;
 229         }
 230
 231         if ((cur = tb[ROUTE_MTU]) != NULL)
 232                 route->mtu = blobmsg_get_u32(cur);
 233
 234         vlist_add(&ip->route, &route->node, &route->flags);
 235         return;
 236
 237 error:
 238         free(route);
 239 }
 240
 241 static int
 242 addr_cmp(const void *k1, const void *k2, void *ptr)
 243 {
 244         return memcmp(k1, k2, sizeof(struct device_addr) -
 245                       offsetof(struct device_addr, flags));
 246 }
 247
 248 static int
 249 route_cmp(const void *k1, const void *k2, void *ptr)
 250 {
 251         return memcmp(k1, k2, sizeof(struct device_route) -
 252                       offsetof(struct device_route, flags));
 253 }
 254
 255 static void
 256 interface_handle_subnet_route(struct interface *iface, struct device_addr *addr, bool add)
 257 {
 258         struct device *dev = iface->l3_dev.dev;
 259         struct device_route route;
 260
 261         route.iface = iface;
 262         route.flags = addr->flags;
 263         route.mask = addr->mask;
 264         memcpy(&route.addr, &addr->addr, sizeof(route.addr));
 265         clear_if_addr(&route.addr, route.mask);
 266
 267         if (add) {
 268                 route.flags |= DEVADDR_KERNEL;
 269                 system_del_route(dev, &route);
 270
 271                 route.flags &= ~DEVADDR_KERNEL;
 272                 route.metric = iface->metric;
 273                 system_add_route(dev, &route);
 274         } else {
 275                 system_del_route(dev, &route);
 276         }
 277 }
 278
 279 static void
 280 interface_update_proto_addr(struct vlist_tree *tree,
 281                             struct vlist_node *node_new,
 282                             struct vlist_node *node_old)
 283 {
 284         struct interface_ip_settings *ip;
 285         struct interface *iface;
 286         struct device *dev;
 287         struct device_addr *a_new = NULL, *a_old = NULL;
 288         bool keep = false;
 289
 290         ip = container_of(tree, struct interface_ip_settings, addr);
 291         iface = ip->iface;
 292         dev = iface->l3_dev.dev;
 293
 294         if (node_new) {
 295                 a_new = container_of(node_new, struct device_addr, node);
 296
 297                 if ((a_new->flags & DEVADDR_FAMILY) == DEVADDR_INET4 &&
 298                     !a_new->broadcast) {
 299
 300                         uint32_t mask = ~0;
 301                         uint32_t *a = (uint32_t *) &a_new->addr;
 302
 303                         mask >>= a_new->mask;
 304                         a_new->broadcast = *a | mask;
 305                 }
 306         }
 307
 308         if (node_old)
 309                 a_old = container_of(node_old, struct device_addr, node);
 310
 311         if (a_new && a_old) {
 312                 keep = true;
 313
 314                 if (a_old->flags != a_new->flags)
 315                         keep = false;
 316
 317                 if ((a_new->flags & DEVADDR_FAMILY) == DEVADDR_INET4 &&
 318                     a_new->broadcast != a_old->broadcast)
 319                         keep = false;
 320         }
 321
 322         if (node_old) {
 323                 if (!(a_old->flags & DEVADDR_EXTERNAL) && a_old->enabled && !keep) {
 324                         interface_handle_subnet_route(iface, a_old, false);
 325                         system_del_address(dev, a_old);
 326                 }
 327                 free(a_old);
 328         }
 329
 330         if (node_new) {
 331                 a_new->enabled = true;
 332                 if (!(a_new->flags & DEVADDR_EXTERNAL) && !keep) {
 333                         system_add_address(dev, a_new);
 334                         if (iface->metric)
 335                                 interface_handle_subnet_route(iface, a_new, true);
 336                 }
 337         }
 338 }
 339
 340 static bool
 341 enable_route(struct interface_ip_settings *ip, struct device_route *route)
 342 {
 343         if (ip->no_defaultroute && !route->mask)
 344                 return false;
 345
 346         return ip->enabled;
 347 }
 348
 349 static void
 350 interface_update_proto_route(struct vlist_tree *tree,
 351                              struct vlist_node *node_new,
 352                              struct vlist_node *node_old)
 353 {
 354         struct interface_ip_settings *ip;
 355         struct interface *iface;
 356         struct device *dev;
 357         struct device_route *route_old, *route_new;
 358         bool keep = false;
 359
 360         ip = container_of(tree, struct interface_ip_settings, route);
 361         iface = ip->iface;
 362         dev = iface->l3_dev.dev;
 363
 364         route_old = container_of(node_old, struct device_route, node);
 365         route_new = container_of(node_new, struct device_route, node);
 366
 367         if (node_old && node_new)
 368                 keep = !memcmp(&route_old->nexthop, &route_new->nexthop, sizeof(route_old->nexthop));
 369
 370         if (node_old) {
 371                 if (!(route_old->flags & DEVADDR_EXTERNAL) && route_old->enabled && !keep)
 372                         system_del_route(dev, route_old);
 373                 free(route_old);
 374         }
 375
 376         if (node_new) {
 377                 bool _enabled = enable_route(ip, route_new);
 378
 379                 if (!(route_new->flags & DEVROUTE_METRIC))
 380                         route_new->metric = iface->metric;
 381
 382                 if (!(route_new->flags & DEVADDR_EXTERNAL) && !keep && _enabled)
 383                         system_add_route(dev, route_new);
 384
 385                 route_new->iface = iface;
 386                 route_new->enabled = _enabled;
 387         }
 388 }
 389
 390 static void
 391 interface_update_host_route(struct vlist_tree *tree,
 392                              struct vlist_node *node_new,
 393                              struct vlist_node *node_old)
 394 {
 395         struct interface *iface;
 396         struct device *dev;
 397         struct device_route *route_old, *route_new;
 398
 399         iface = container_of(tree, struct interface, host_routes);
 400         dev = iface->l3_dev.dev;
 401
 402         route_old = container_of(node_old, struct device_route, node);
 403         route_new = container_of(node_new, struct device_route, node);
 404
 405         if (node_old) {
 406                 system_del_route(dev, route_old);
 407                 free(route_old);
 408         }
 409
 410         if (node_new)
 411                 system_add_route(dev, route_new);
 412 }
 413
 414 void
 415 interface_add_dns_server(struct interface_ip_settings *ip, const char *str)
 416 {
 417         struct dns_server *s;
 418
 419         s = calloc(1, sizeof(*s));
 420         s->af = AF_INET;
 421         if (inet_pton(s->af, str, &s->addr.in))
 422                 goto add;
 423
 424         s->af = AF_INET6;
 425         if (inet_pton(s->af, str, &s->addr.in))
 426                 goto add;
 427
 428         free(s);
 429         return;
 430
 431 add:
 432         D(INTERFACE, "Add IPv%c DNS server: %s\n",
 433           s->af == AF_INET6 ? '6' : '4', str);
 434         vlist_simple_add(&ip->dns_servers, &s->node);
 435 }
 436
 437 void
 438 interface_add_dns_server_list(struct interface_ip_settings *ip, struct blob_attr *list)
 439 {
 440         struct blob_attr *cur;
 441         int rem;
 442
 443         blobmsg_for_each_attr(cur, list, rem) {
 444                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 445                         continue;
 446
 447                 if (!blobmsg_check_attr(cur, NULL))
 448                         continue;
 449
 450                 interface_add_dns_server(ip, blobmsg_data(cur));
 451         }
 452 }
 453
 454 static void
 455 interface_add_dns_search_domain(struct interface_ip_settings *ip, const char *str)
 456 {
 457         struct dns_search_domain *s;
 458         int len = strlen(str);
 459
 460         s = calloc(1, sizeof(*s) + len + 1);
 461         if (!s)
 462                 return;
 463
 464         D(INTERFACE, "Add DNS search domain: %s\n", str);
 465         memcpy(s->name, str, len);
 466         vlist_simple_add(&ip->dns_search, &s->node);
 467 }
 468
 469 void
 470 interface_add_dns_search_list(struct interface_ip_settings *ip, struct blob_attr *list)
 471 {
 472         struct blob_attr *cur;
 473         int rem;
 474
 475         blobmsg_for_each_attr(cur, list, rem) {
 476                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 477                         continue;
 478
 479                 if (!blobmsg_check_attr(cur, NULL))
 480                         continue;
 481
 482                 interface_add_dns_search_domain(ip, blobmsg_data(cur));
 483         }
 484 }
 485
 486 static void
 487 write_resolv_conf_entries(FILE *f, struct interface_ip_settings *ip)
 488 {
 489         struct dns_server *s;
 490         struct dns_search_domain *d;
 491         const char *str;
 492         char buf[32];
 493
 494         vlist_simple_for_each_element(&ip->dns_servers, s, node) {
 495                 str = inet_ntop(s->af, &s->addr, buf, sizeof(buf));
 496                 if (!str)
 497                         continue;
 498
 499                 fprintf(f, "nameserver %s\n", str);
 500         }
 501
 502         vlist_simple_for_each_element(&ip->dns_search, d, node) {
 503                 fprintf(f, "search %s\n", d->name);
 504         }
 505 }
 506
 507 void
 508 interface_write_resolv_conf(void)
 509 {
 510         struct interface *iface;
 511         char *path = alloca(strlen(resolv_conf) + 5);
 512         FILE *f;
 513
 514         sprintf(path, "%s.tmp", resolv_conf);
 515         unlink(path);
 516         f = fopen(path, "w");
 517         if (!f) {
 518                 D(INTERFACE, "Failed to open %s for writing\n", path);
 519                 return;
 520         }
 521
 522         vlist_for_each_element(&interfaces, iface, node) {
 523                 if (iface->state != IFS_UP)
 524                         continue;
 525
 526                 if (vlist_simple_empty(&iface->proto_ip.dns_search) &&
 527                     vlist_simple_empty(&iface->proto_ip.dns_servers) &&
 528                         vlist_simple_empty(&iface->config_ip.dns_search) &&
 529                     vlist_simple_empty(&iface->config_ip.dns_servers))
 530                         continue;
 531
 532                 fprintf(f, "# Interface %s\n", iface->name);
 533                 write_resolv_conf_entries(f, &iface->config_ip);
 534                 if (!iface->proto_ip.no_dns)
 535                         write_resolv_conf_entries(f, &iface->proto_ip);
 536         }
 537         fclose(f);
 538         if (rename(path, resolv_conf) < 0) {
 539                 D(INTERFACE, "Failed to replace %s\n", resolv_conf);
 540                 unlink(path);
 541         }
 542 }
 543
 544 void interface_ip_set_enabled(struct interface_ip_settings *ip, bool enabled)
 545 {
 546         struct device_addr *addr;
 547         struct device_route *route;
 548         struct device *dev;
 549
 550         ip->enabled = enabled;
 551         dev = ip->iface->l3_dev.dev;
 552         if (!dev)
 553                 return;
 554
 555         vlist_for_each_element(&ip->addr, addr, node) {
 556                 if (addr->enabled == enabled)
 557                         continue;
 558
 559                 if (enabled)
 560                         system_add_address(dev, addr);
 561                 else
 562                         system_del_address(dev, addr);
 563                 addr->enabled = enabled;
 564         }
 565
 566         vlist_for_each_element(&ip->route, route, node) {
 567                 bool _enabled = enabled;
 568
 569                 if (!enable_route(ip, route))
 570                         _enabled = false;
 571
 572                 if (route->enabled == _enabled)
 573                         continue;
 574
 575                 if (_enabled) {
 576                         if (!(route->flags & DEVROUTE_METRIC))
 577                                 route->metric = ip->iface->metric;
 578
 579                         system_add_route(dev, route);
 580                 } else
 581                         system_del_route(dev, route);
 582                 route->enabled = _enabled;
 583         }
 584 }
 585
 586 void
 587 interface_ip_update_start(struct interface_ip_settings *ip)
 588 {
 589         if (ip != &ip->iface->config_ip) {
 590                 vlist_simple_update(&ip->dns_servers);
 591                 vlist_simple_update(&ip->dns_search);
 592         }
 593         vlist_update(&ip->route);
 594         vlist_update(&ip->addr);
 595 }
 596
 597 void
 598 interface_ip_update_complete(struct interface_ip_settings *ip)
 599 {
 600         vlist_simple_flush(&ip->dns_servers);
 601         vlist_simple_flush(&ip->dns_search);
 602         vlist_flush(&ip->route);
 603         vlist_flush(&ip->addr);
 604 }
 605
 606 void
 607 interface_ip_flush(struct interface_ip_settings *ip)
 608 {
 609         if (ip == &ip->iface->proto_ip)
 610                 vlist_flush_all(&ip->iface->host_routes);
 611         vlist_simple_flush_all(&ip->dns_servers);
 612         vlist_simple_flush_all(&ip->dns_search);
 613         vlist_flush_all(&ip->route);
 614         vlist_flush_all(&ip->addr);
 615 }
 616
 617 static void
 618 __interface_ip_init(struct interface_ip_settings *ip, struct interface *iface)
 619 {
 620         ip->iface = iface;
 621         ip->enabled = true;
 622         vlist_simple_init(&ip->dns_search, struct dns_search_domain, node);
 623         vlist_simple_init(&ip->dns_servers, struct dns_server, node);
 624         vlist_init(&ip->route, route_cmp, interface_update_proto_route);
 625         vlist_init(&ip->addr, addr_cmp, interface_update_proto_addr);
 626 }
 627
 628 void
 629 interface_ip_init(struct interface *iface)
 630 {
 631         __interface_ip_init(&iface->proto_ip, iface);
 632         __interface_ip_init(&iface->config_ip, iface);
 633         vlist_init(&iface->host_routes, route_cmp, interface_update_host_route);
 634 }