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