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
 244         vlist_add(&ip->route, &route->node, &route->flags);
 245         return;
 246
 247 error:
 248         free(route);
 249 }
 250
 251 static int
 252 addr_cmp(const void *k1, const void *k2, void *ptr)
 253 {
 254         return memcmp(k1, k2, sizeof(struct device_addr) -
 255                       offsetof(struct device_addr, flags));
 256 }
 257
 258 static int
 259 route_cmp(const void *k1, const void *k2, void *ptr)
 260 {
 261         return memcmp(k1, k2, sizeof(struct device_route) -
 262                       offsetof(struct device_route, flags));
 263 }
 264
 265 static void
 266 interface_handle_subnet_route(struct interface *iface, struct device_addr *addr, bool add)
 267 {
 268         struct device *dev = iface->l3_dev.dev;
 269         struct device_route route;
 270
 271         route.iface = iface;
 272         route.flags = addr->flags;
 273         route.mask = addr->mask;
 274         memcpy(&route.addr, &addr->addr, sizeof(route.addr));
 275         clear_if_addr(&route.addr, route.mask);
 276
 277         if (add) {
 278                 route.flags |= DEVADDR_KERNEL;
 279                 system_del_route(dev, &route);
 280
 281                 route.flags &= ~DEVADDR_KERNEL;
 282                 route.metric = iface->metric;
 283                 system_add_route(dev, &route);
 284         } else {
 285                 system_del_route(dev, &route);
 286         }
 287 }
 288
 289 static void
 290 interface_update_proto_addr(struct vlist_tree *tree,
 291                             struct vlist_node *node_new,
 292                             struct vlist_node *node_old)
 293 {
 294         struct interface_ip_settings *ip;
 295         struct interface *iface;
 296         struct device *dev;
 297         struct device_addr *a_new = NULL, *a_old = NULL;
 298         bool keep = false;
 299
 300         ip = container_of(tree, struct interface_ip_settings, addr);
 301         iface = ip->iface;
 302         dev = iface->l3_dev.dev;
 303
 304         if (node_new) {
 305                 a_new = container_of(node_new, struct device_addr, node);
 306
 307                 if ((a_new->flags & DEVADDR_FAMILY) == DEVADDR_INET4 &&
 308                     !a_new->broadcast) {
 309
 310                         uint32_t mask = ~0;
 311                         uint32_t *a = (uint32_t *) &a_new->addr;
 312
 313                         mask >>= a_new->mask;
 314                         a_new->broadcast = *a | htonl(mask);
 315                 }
 316         }
 317
 318         if (node_old)
 319                 a_old = container_of(node_old, struct device_addr, node);
 320
 321         if (a_new && a_old) {
 322                 keep = true;
 323
 324                 if (a_old->flags != a_new->flags)
 325                         keep = false;
 326
 327                 if ((a_new->flags & DEVADDR_FAMILY) == DEVADDR_INET4 &&
 328                     a_new->broadcast != a_old->broadcast)
 329                         keep = false;
 330         }
 331
 332         if (node_old) {
 333                 if (!(a_old->flags & DEVADDR_EXTERNAL) && a_old->enabled && !keep) {
 334                         interface_handle_subnet_route(iface, a_old, false);
 335                         system_del_address(dev, a_old);
 336                 }
 337                 free(a_old);
 338         }
 339
 340         if (node_new) {
 341                 a_new->enabled = true;
 342                 if (!(a_new->flags & DEVADDR_EXTERNAL) && !keep) {
 343                         system_add_address(dev, a_new);
 344                         if (iface->metric)
 345                                 interface_handle_subnet_route(iface, a_new, true);
 346                 }
 347         }
 348 }
 349
 350 static bool
 351 enable_route(struct interface_ip_settings *ip, struct device_route *route)
 352 {
 353         if (ip->no_defaultroute && !route->mask)
 354                 return false;
 355
 356         return ip->enabled;
 357 }
 358
 359 static void
 360 interface_update_proto_route(struct vlist_tree *tree,
 361                              struct vlist_node *node_new,
 362                              struct vlist_node *node_old)
 363 {
 364         struct interface_ip_settings *ip;
 365         struct interface *iface;
 366         struct device *dev;
 367         struct device_route *route_old, *route_new;
 368         bool keep = false;
 369
 370         ip = container_of(tree, struct interface_ip_settings, route);
 371         iface = ip->iface;
 372         dev = iface->l3_dev.dev;
 373
 374         route_old = container_of(node_old, struct device_route, node);
 375         route_new = container_of(node_new, struct device_route, node);
 376
 377         if (node_old && node_new)
 378                 keep = !memcmp(&route_old->nexthop, &route_new->nexthop, sizeof(route_old->nexthop));
 379
 380         if (node_old) {
 381                 if (!(route_old->flags & DEVADDR_EXTERNAL) && route_old->enabled && !keep)
 382                         system_del_route(dev, route_old);
 383                 free(route_old);
 384         }
 385
 386         if (node_new) {
 387                 bool _enabled = enable_route(ip, route_new);
 388
 389                 if (!(route_new->flags & DEVROUTE_METRIC))
 390                         route_new->metric = iface->metric;
 391
 392                 if (!(route_new->flags & DEVADDR_EXTERNAL) && !keep && _enabled)
 393                         system_add_route(dev, route_new);
 394
 395                 route_new->iface = iface;
 396                 route_new->enabled = _enabled;
 397         }
 398 }
 399
 400 static void
 401 interface_update_host_route(struct vlist_tree *tree,
 402                              struct vlist_node *node_new,
 403                              struct vlist_node *node_old)
 404 {
 405         struct interface *iface;
 406         struct device *dev;
 407         struct device_route *route_old, *route_new;
 408
 409         iface = container_of(tree, struct interface, host_routes);
 410         dev = iface->l3_dev.dev;
 411
 412         route_old = container_of(node_old, struct device_route, node);
 413         route_new = container_of(node_new, struct device_route, node);
 414
 415         if (node_old) {
 416                 system_del_route(dev, route_old);
 417                 free(route_old);
 418         }
 419
 420         if (node_new)
 421                 system_add_route(dev, route_new);
 422 }
 423
 424 void
 425 interface_add_dns_server(struct interface_ip_settings *ip, const char *str)
 426 {
 427         struct dns_server *s;
 428
 429         s = calloc(1, sizeof(*s));
 430         s->af = AF_INET;
 431         if (inet_pton(s->af, str, &s->addr.in))
 432                 goto add;
 433
 434         s->af = AF_INET6;
 435         if (inet_pton(s->af, str, &s->addr.in))
 436                 goto add;
 437
 438         free(s);
 439         return;
 440
 441 add:
 442         D(INTERFACE, "Add IPv%c DNS server: %s\n",
 443           s->af == AF_INET6 ? '6' : '4', str);
 444         vlist_simple_add(&ip->dns_servers, &s->node);
 445 }
 446
 447 void
 448 interface_add_dns_server_list(struct interface_ip_settings *ip, struct blob_attr *list)
 449 {
 450         struct blob_attr *cur;
 451         int rem;
 452
 453         blobmsg_for_each_attr(cur, list, rem) {
 454                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 455                         continue;
 456
 457                 if (!blobmsg_check_attr(cur, NULL))
 458                         continue;
 459
 460                 interface_add_dns_server(ip, blobmsg_data(cur));
 461         }
 462 }
 463
 464 static void
 465 interface_add_dns_search_domain(struct interface_ip_settings *ip, const char *str)
 466 {
 467         struct dns_search_domain *s;
 468         int len = strlen(str);
 469
 470         s = calloc(1, sizeof(*s) + len + 1);
 471         if (!s)
 472                 return;
 473
 474         D(INTERFACE, "Add DNS search domain: %s\n", str);
 475         memcpy(s->name, str, len);
 476         vlist_simple_add(&ip->dns_search, &s->node);
 477 }
 478
 479 void
 480 interface_add_dns_search_list(struct interface_ip_settings *ip, struct blob_attr *list)
 481 {
 482         struct blob_attr *cur;
 483         int rem;
 484
 485         blobmsg_for_each_attr(cur, list, rem) {
 486                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 487                         continue;
 488
 489                 if (!blobmsg_check_attr(cur, NULL))
 490                         continue;
 491
 492                 interface_add_dns_search_domain(ip, blobmsg_data(cur));
 493         }
 494 }
 495
 496 static void
 497 write_resolv_conf_entries(FILE *f, struct interface_ip_settings *ip)
 498 {
 499         struct dns_server *s;
 500         struct dns_search_domain *d;
 501         const char *str;
 502         char buf[32];
 503
 504         vlist_simple_for_each_element(&ip->dns_servers, s, node) {
 505                 str = inet_ntop(s->af, &s->addr, buf, sizeof(buf));
 506                 if (!str)
 507                         continue;
 508
 509                 fprintf(f, "nameserver %s\n", str);
 510         }
 511
 512         vlist_simple_for_each_element(&ip->dns_search, d, node) {
 513                 fprintf(f, "search %s\n", d->name);
 514         }
 515 }
 516
 517 void
 518 interface_write_resolv_conf(void)
 519 {
 520         struct interface *iface;
 521         char *path = alloca(strlen(resolv_conf) + 5);
 522         FILE *f;
 523
 524         sprintf(path, "%s.tmp", resolv_conf);
 525         unlink(path);
 526         f = fopen(path, "w");
 527         if (!f) {
 528                 D(INTERFACE, "Failed to open %s for writing\n", path);
 529                 return;
 530         }
 531
 532         vlist_for_each_element(&interfaces, iface, node) {
 533                 if (iface->state != IFS_UP)
 534                         continue;
 535
 536                 if (vlist_simple_empty(&iface->proto_ip.dns_search) &&
 537                     vlist_simple_empty(&iface->proto_ip.dns_servers) &&
 538                         vlist_simple_empty(&iface->config_ip.dns_search) &&
 539                     vlist_simple_empty(&iface->config_ip.dns_servers))
 540                         continue;
 541
 542                 fprintf(f, "# Interface %s\n", iface->name);
 543                 write_resolv_conf_entries(f, &iface->config_ip);
 544                 if (!iface->proto_ip.no_dns)
 545                         write_resolv_conf_entries(f, &iface->proto_ip);
 546         }
 547         fclose(f);
 548         if (rename(path, resolv_conf) < 0) {
 549                 D(INTERFACE, "Failed to replace %s\n", resolv_conf);
 550                 unlink(path);
 551         }
 552 }
 553
 554 void interface_ip_set_enabled(struct interface_ip_settings *ip, bool enabled)
 555 {
 556         struct device_addr *addr;
 557         struct device_route *route;
 558         struct device *dev;
 559
 560         ip->enabled = enabled;
 561         dev = ip->iface->l3_dev.dev;
 562         if (!dev)
 563                 return;
 564
 565         vlist_for_each_element(&ip->addr, addr, node) {
 566                 if (addr->enabled == enabled)
 567                         continue;
 568
 569                 if (enabled)
 570                         system_add_address(dev, addr);
 571                 else
 572                         system_del_address(dev, addr);
 573                 addr->enabled = enabled;
 574         }
 575
 576         vlist_for_each_element(&ip->route, route, node) {
 577                 bool _enabled = enabled;
 578
 579                 if (!enable_route(ip, route))
 580                         _enabled = false;
 581
 582                 if (route->enabled == _enabled)
 583                         continue;
 584
 585                 if (_enabled) {
 586                         if (!(route->flags & DEVROUTE_METRIC))
 587                                 route->metric = ip->iface->metric;
 588
 589                         system_add_route(dev, route);
 590                 } else
 591                         system_del_route(dev, route);
 592                 route->enabled = _enabled;
 593         }
 594 }
 595
 596 void
 597 interface_ip_update_start(struct interface_ip_settings *ip)
 598 {
 599         if (ip != &ip->iface->config_ip) {
 600                 vlist_simple_update(&ip->dns_servers);
 601                 vlist_simple_update(&ip->dns_search);
 602         }
 603         vlist_update(&ip->route);
 604         vlist_update(&ip->addr);
 605 }
 606
 607 void
 608 interface_ip_update_complete(struct interface_ip_settings *ip)
 609 {
 610         vlist_simple_flush(&ip->dns_servers);
 611         vlist_simple_flush(&ip->dns_search);
 612         vlist_flush(&ip->route);
 613         vlist_flush(&ip->addr);
 614 }
 615
 616 void
 617 interface_ip_flush(struct interface_ip_settings *ip)
 618 {
 619         if (ip == &ip->iface->proto_ip)
 620                 vlist_flush_all(&ip->iface->host_routes);
 621         vlist_simple_flush_all(&ip->dns_servers);
 622         vlist_simple_flush_all(&ip->dns_search);
 623         vlist_flush_all(&ip->route);
 624         vlist_flush_all(&ip->addr);
 625 }
 626
 627 static void
 628 __interface_ip_init(struct interface_ip_settings *ip, struct interface *iface)
 629 {
 630         ip->iface = iface;
 631         ip->enabled = true;
 632         vlist_simple_init(&ip->dns_search, struct dns_search_domain, node);
 633         vlist_simple_init(&ip->dns_servers, struct dns_server, node);
 634         vlist_init(&ip->route, route_cmp, interface_update_proto_route);
 635         vlist_init(&ip->addr, addr_cmp, interface_update_proto_addr);
 636 }
 637
 638 void
 639 interface_ip_init(struct interface *iface)
 640 {
 641         __interface_ip_init(&iface->proto_ip, iface);
 642         __interface_ip_init(&iface->config_ip, iface);
 643         vlist_init(&iface->host_routes, route_cmp, interface_update_host_route);
 644 }