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         bool defaultroute_target = false;
 145         int addrsize = v6 ? sizeof(addr->in6) : sizeof(addr->in);
 146
 147         route = calloc(1, sizeof(*route));
 148         if (!route)
 149                 return NULL;
 150
 151         route->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4;
 152         route->mask = v6 ? 128 : 32;
 153         if (memcmp(&route->addr, addr, addrsize) == 0)
 154                 defaultroute_target = true;
 155         else
 156                 memcpy(&route->addr, addr, addrsize);
 157
 158         vlist_for_each_element(&interfaces, iface, node) {
 159                 /* look for locally addressable target first */
 160                 if (interface_ip_find_addr_target(iface, addr, v6))
 161                         goto done;
 162
 163                 /* do not stop at the first route, let the lookup compare
 164                  * masks to find the best match */
 165                 interface_ip_find_route_target(iface, addr, v6, &r_next);
 166         }
 167
 168         if (!r_next) {
 169                 free(route);
 170                 return NULL;
 171         }
 172
 173         iface = r_next->iface;
 174         memcpy(&route->nexthop, &r_next->nexthop, sizeof(route->nexthop));
 175         route->mtu = r_next->mtu;
 176         route->metric = r_next->metric;
 177
 178 done:
 179         route->iface = iface;
 180         if (defaultroute_target)
 181                 free(route);
 182         else
 183                 vlist_add(&iface->host_routes, &route->node, &route->flags);
 184         return iface;
 185 }
 186
 187 void
 188 interface_ip_add_route(struct interface *iface, struct blob_attr *attr, bool v6)
 189 {
 190         struct interface_ip_settings *ip;
 191         struct blob_attr *tb[__ROUTE_MAX], *cur;
 192         struct device_route *route;
 193         int af = v6 ? AF_INET6 : AF_INET;
 194
 195         blobmsg_parse(route_attr, __ROUTE_MAX, tb, blobmsg_data(attr), blobmsg_data_len(attr));
 196
 197         if (!iface) {
 198                 if ((cur = tb[ROUTE_INTERFACE]) == NULL)
 199                         return;
 200
 201                 iface = vlist_find(&interfaces, blobmsg_data(cur), iface, node);
 202                 if (!iface)
 203                         return;
 204
 205                 ip = &iface->config_ip;
 206         } else {
 207                 ip = &iface->proto_ip;
 208         }
 209
 210         route = calloc(1, sizeof(*route));
 211         if (!route)
 212                 return;
 213
 214         route->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4;
 215         route->mask = v6 ? 128 : 32;
 216         if ((cur = tb[ROUTE_MASK]) != NULL) {
 217                 route->mask = parse_netmask_string(blobmsg_data(cur), v6);
 218                 if (route->mask > (v6 ? 128 : 32))
 219                         goto error;
 220         }
 221
 222         if ((cur = tb[ROUTE_TARGET]) != NULL) {
 223                 if (!parse_ip_and_netmask(af, blobmsg_data(cur), &route->addr, &route->mask)) {
 224                         DPRINTF("Failed to parse route target: %s\n", (char *) blobmsg_data(cur));
 225                         goto error;
 226                 }
 227         }
 228
 229         if ((cur = tb[ROUTE_GATEWAY]) != NULL) {
 230                 if (!inet_pton(af, blobmsg_data(cur), &route->nexthop)) {
 231                         DPRINTF("Failed to parse route gateway: %s\n", (char *) blobmsg_data(cur));
 232                         goto error;
 233                 }
 234         }
 235
 236         if ((cur = tb[ROUTE_METRIC]) != NULL) {
 237                 route->metric = blobmsg_get_u32(cur);
 238                 route->flags |= DEVROUTE_METRIC;
 239         }
 240
 241         if ((cur = tb[ROUTE_MTU]) != NULL) {
 242                 route->mtu = blobmsg_get_u32(cur);
 243                 route->flags |= DEVROUTE_MTU;
 244         }
 245
 246         vlist_add(&ip->route, &route->node, &route->flags);
 247         return;
 248
 249 error:
 250         free(route);
 251 }
 252
 253 static int
 254 addr_cmp(const void *k1, const void *k2, void *ptr)
 255 {
 256         return memcmp(k1, k2, sizeof(struct device_addr) -
 257                       offsetof(struct device_addr, flags));
 258 }
 259
 260 static int
 261 route_cmp(const void *k1, const void *k2, void *ptr)
 262 {
 263         return memcmp(k1, k2, sizeof(struct device_route) -
 264                       offsetof(struct device_route, flags));
 265 }
 266
 267 static void
 268 interface_handle_subnet_route(struct interface *iface, struct device_addr *addr, bool add)
 269 {
 270         struct device *dev = iface->l3_dev.dev;
 271         struct device_route route;
 272
 273         memset(&route, 0, sizeof(route));
 274         route.iface = iface;
 275         route.flags = addr->flags;
 276         route.mask = addr->mask;
 277         memcpy(&route.addr, &addr->addr, sizeof(route.addr));
 278         clear_if_addr(&route.addr, route.mask);
 279
 280         if (add) {
 281                 route.flags |= DEVADDR_KERNEL;
 282                 system_del_route(dev, &route);
 283
 284                 route.flags &= ~DEVADDR_KERNEL;
 285                 route.metric = iface->metric;
 286                 system_add_route(dev, &route);
 287         } else {
 288                 system_del_route(dev, &route);
 289         }
 290 }
 291
 292 static void
 293 interface_update_proto_addr(struct vlist_tree *tree,
 294                             struct vlist_node *node_new,
 295                             struct vlist_node *node_old)
 296 {
 297         struct interface_ip_settings *ip;
 298         struct interface *iface;
 299         struct device *dev;
 300         struct device_addr *a_new = NULL, *a_old = NULL;
 301         bool keep = false;
 302
 303         ip = container_of(tree, struct interface_ip_settings, addr);
 304         iface = ip->iface;
 305         dev = iface->l3_dev.dev;
 306
 307         if (node_new) {
 308                 a_new = container_of(node_new, struct device_addr, node);
 309
 310                 if ((a_new->flags & DEVADDR_FAMILY) == DEVADDR_INET4 &&
 311                     !a_new->broadcast) {
 312
 313                         uint32_t mask = ~0;
 314                         uint32_t *a = (uint32_t *) &a_new->addr;
 315
 316                         mask >>= a_new->mask;
 317                         a_new->broadcast = *a | htonl(mask);
 318                 }
 319         }
 320
 321         if (node_old)
 322                 a_old = container_of(node_old, struct device_addr, node);
 323
 324         if (a_new && a_old) {
 325                 keep = true;
 326
 327                 if (a_old->flags != a_new->flags)
 328                         keep = false;
 329
 330                 if ((a_new->flags & DEVADDR_FAMILY) == DEVADDR_INET4 &&
 331                     a_new->broadcast != a_old->broadcast)
 332                         keep = false;
 333         }
 334
 335         if (node_old) {
 336                 if (!(a_old->flags & DEVADDR_EXTERNAL) && a_old->enabled && !keep) {
 337                         interface_handle_subnet_route(iface, a_old, false);
 338                         system_del_address(dev, a_old);
 339                 }
 340                 free(a_old);
 341         }
 342
 343         if (node_new) {
 344                 a_new->enabled = true;
 345                 if (!(a_new->flags & DEVADDR_EXTERNAL) && !keep) {
 346                         system_add_address(dev, a_new);
 347                         if (iface->metric)
 348                                 interface_handle_subnet_route(iface, a_new, true);
 349                 }
 350         }
 351 }
 352
 353 static bool
 354 enable_route(struct interface_ip_settings *ip, struct device_route *route)
 355 {
 356         if (ip->no_defaultroute && !route->mask)
 357                 return false;
 358
 359         return ip->enabled;
 360 }
 361
 362 static void
 363 interface_update_proto_route(struct vlist_tree *tree,
 364                              struct vlist_node *node_new,
 365                              struct vlist_node *node_old)
 366 {
 367         struct interface_ip_settings *ip;
 368         struct interface *iface;
 369         struct device *dev;
 370         struct device_route *route_old, *route_new;
 371         bool keep = false;
 372
 373         ip = container_of(tree, struct interface_ip_settings, route);
 374         iface = ip->iface;
 375         dev = iface->l3_dev.dev;
 376
 377         route_old = container_of(node_old, struct device_route, node);
 378         route_new = container_of(node_new, struct device_route, node);
 379
 380         if (node_old && node_new)
 381                 keep = !memcmp(&route_old->nexthop, &route_new->nexthop, sizeof(route_old->nexthop));
 382
 383         if (node_old) {
 384                 if (!(route_old->flags & DEVADDR_EXTERNAL) && route_old->enabled && !keep)
 385                         system_del_route(dev, route_old);
 386                 free(route_old);
 387         }
 388
 389         if (node_new) {
 390                 bool _enabled = enable_route(ip, route_new);
 391
 392                 if (!(route_new->flags & DEVROUTE_METRIC))
 393                         route_new->metric = iface->metric;
 394
 395                 if (!(route_new->flags & DEVADDR_EXTERNAL) && !keep && _enabled)
 396                         system_add_route(dev, route_new);
 397
 398                 route_new->iface = iface;
 399                 route_new->enabled = _enabled;
 400         }
 401 }
 402
 403 static void
 404 interface_update_host_route(struct vlist_tree *tree,
 405                              struct vlist_node *node_new,
 406                              struct vlist_node *node_old)
 407 {
 408         struct interface *iface;
 409         struct device *dev;
 410         struct device_route *route_old, *route_new;
 411
 412         iface = container_of(tree, struct interface, host_routes);
 413         dev = iface->l3_dev.dev;
 414
 415         route_old = container_of(node_old, struct device_route, node);
 416         route_new = container_of(node_new, struct device_route, node);
 417
 418         if (node_old) {
 419                 system_del_route(dev, route_old);
 420                 free(route_old);
 421         }
 422
 423         if (node_new)
 424                 system_add_route(dev, route_new);
 425 }
 426
 427 void
 428 interface_add_dns_server(struct interface_ip_settings *ip, const char *str)
 429 {
 430         struct dns_server *s;
 431
 432         s = calloc(1, sizeof(*s));
 433         if (!s)
 434                 return;
 435
 436         s->af = AF_INET;
 437         if (inet_pton(s->af, str, &s->addr.in))
 438                 goto add;
 439
 440         s->af = AF_INET6;
 441         if (inet_pton(s->af, str, &s->addr.in))
 442                 goto add;
 443
 444         free(s);
 445         return;
 446
 447 add:
 448         D(INTERFACE, "Add IPv%c DNS server: %s\n",
 449           s->af == AF_INET6 ? '6' : '4', str);
 450         vlist_simple_add(&ip->dns_servers, &s->node);
 451 }
 452
 453 void
 454 interface_add_dns_server_list(struct interface_ip_settings *ip, struct blob_attr *list)
 455 {
 456         struct blob_attr *cur;
 457         int rem;
 458
 459         blobmsg_for_each_attr(cur, list, rem) {
 460                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 461                         continue;
 462
 463                 if (!blobmsg_check_attr(cur, NULL))
 464                         continue;
 465
 466                 interface_add_dns_server(ip, blobmsg_data(cur));
 467         }
 468 }
 469
 470 static void
 471 interface_add_dns_search_domain(struct interface_ip_settings *ip, const char *str)
 472 {
 473         struct dns_search_domain *s;
 474         int len = strlen(str);
 475
 476         s = calloc(1, sizeof(*s) + len + 1);
 477         if (!s)
 478                 return;
 479
 480         D(INTERFACE, "Add DNS search domain: %s\n", str);
 481         memcpy(s->name, str, len);
 482         vlist_simple_add(&ip->dns_search, &s->node);
 483 }
 484
 485 void
 486 interface_add_dns_search_list(struct interface_ip_settings *ip, struct blob_attr *list)
 487 {
 488         struct blob_attr *cur;
 489         int rem;
 490
 491         blobmsg_for_each_attr(cur, list, rem) {
 492                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 493                         continue;
 494
 495                 if (!blobmsg_check_attr(cur, NULL))
 496                         continue;
 497
 498                 interface_add_dns_search_domain(ip, blobmsg_data(cur));
 499         }
 500 }
 501
 502 static void
 503 write_resolv_conf_entries(FILE *f, struct interface_ip_settings *ip)
 504 {
 505         struct dns_server *s;
 506         struct dns_search_domain *d;
 507         const char *str;
 508         char buf[32];
 509
 510         vlist_simple_for_each_element(&ip->dns_servers, s, node) {
 511                 str = inet_ntop(s->af, &s->addr, buf, sizeof(buf));
 512                 if (!str)
 513                         continue;
 514
 515                 fprintf(f, "nameserver %s\n", str);
 516         }
 517
 518         vlist_simple_for_each_element(&ip->dns_search, d, node) {
 519                 fprintf(f, "search %s\n", d->name);
 520         }
 521 }
 522
 523 void
 524 interface_write_resolv_conf(void)
 525 {
 526         struct interface *iface;
 527         char *path = alloca(strlen(resolv_conf) + 5);
 528         FILE *f;
 529
 530         sprintf(path, "%s.tmp", resolv_conf);
 531         unlink(path);
 532         f = fopen(path, "w");
 533         if (!f) {
 534                 D(INTERFACE, "Failed to open %s for writing\n", path);
 535                 return;
 536         }
 537
 538         vlist_for_each_element(&interfaces, iface, node) {
 539                 if (iface->state != IFS_UP)
 540                         continue;
 541
 542                 if (vlist_simple_empty(&iface->proto_ip.dns_search) &&
 543                     vlist_simple_empty(&iface->proto_ip.dns_servers) &&
 544                         vlist_simple_empty(&iface->config_ip.dns_search) &&
 545                     vlist_simple_empty(&iface->config_ip.dns_servers))
 546                         continue;
 547
 548                 fprintf(f, "# Interface %s\n", iface->name);
 549                 write_resolv_conf_entries(f, &iface->config_ip);
 550                 if (!iface->proto_ip.no_dns)
 551                         write_resolv_conf_entries(f, &iface->proto_ip);
 552         }
 553         fclose(f);
 554         if (rename(path, resolv_conf) < 0) {
 555                 D(INTERFACE, "Failed to replace %s\n", resolv_conf);
 556                 unlink(path);
 557         }
 558 }
 559
 560 void interface_ip_set_enabled(struct interface_ip_settings *ip, bool enabled)
 561 {
 562         struct device_addr *addr;
 563         struct device_route *route;
 564         struct device *dev;
 565
 566         ip->enabled = enabled;
 567         dev = ip->iface->l3_dev.dev;
 568         if (!dev)
 569                 return;
 570
 571         vlist_for_each_element(&ip->addr, addr, node) {
 572                 if (addr->enabled == enabled)
 573                         continue;
 574
 575                 if (enabled)
 576                         system_add_address(dev, addr);
 577                 else
 578                         system_del_address(dev, addr);
 579                 addr->enabled = enabled;
 580         }
 581
 582         vlist_for_each_element(&ip->route, route, node) {
 583                 bool _enabled = enabled;
 584
 585                 if (!enable_route(ip, route))
 586                         _enabled = false;
 587
 588                 if (route->enabled == _enabled)
 589                         continue;
 590
 591                 if (_enabled) {
 592                         if (!(route->flags & DEVROUTE_METRIC))
 593                                 route->metric = ip->iface->metric;
 594
 595                         system_add_route(dev, route);
 596                 } else
 597                         system_del_route(dev, route);
 598                 route->enabled = _enabled;
 599         }
 600 }
 601
 602 void
 603 interface_ip_update_start(struct interface_ip_settings *ip)
 604 {
 605         if (ip != &ip->iface->config_ip) {
 606                 vlist_simple_update(&ip->dns_servers);
 607                 vlist_simple_update(&ip->dns_search);
 608         }
 609         vlist_update(&ip->route);
 610         vlist_update(&ip->addr);
 611 }
 612
 613 void
 614 interface_ip_update_complete(struct interface_ip_settings *ip)
 615 {
 616         vlist_simple_flush(&ip->dns_servers);
 617         vlist_simple_flush(&ip->dns_search);
 618         vlist_flush(&ip->route);
 619         vlist_flush(&ip->addr);
 620         interface_write_resolv_conf();
 621 }
 622
 623 void
 624 interface_ip_flush(struct interface_ip_settings *ip)
 625 {
 626         if (ip == &ip->iface->proto_ip)
 627                 vlist_flush_all(&ip->iface->host_routes);
 628         vlist_simple_flush_all(&ip->dns_servers);
 629         vlist_simple_flush_all(&ip->dns_search);
 630         vlist_flush_all(&ip->route);
 631         vlist_flush_all(&ip->addr);
 632 }
 633
 634 static void
 635 __interface_ip_init(struct interface_ip_settings *ip, struct interface *iface)
 636 {
 637         ip->iface = iface;
 638         ip->enabled = true;
 639         vlist_simple_init(&ip->dns_search, struct dns_search_domain, node);
 640         vlist_simple_init(&ip->dns_servers, struct dns_server, node);
 641         vlist_init(&ip->route, route_cmp, interface_update_proto_route);
 642         vlist_init(&ip->addr, addr_cmp, interface_update_proto_addr);
 643 }
 644
 645 void
 646 interface_ip_init(struct interface *iface)
 647 {
 648         __interface_ip_init(&iface->proto_ip, iface);
 649         __interface_ip_init(&iface->config_ip, iface);
 650         vlist_init(&iface->host_routes, route_cmp, interface_update_host_route);
 651 }