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