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