proto.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
  18 #include <arpa/inet.h>
  19 #include <netinet/in.h>
  20
  21 #include "netifd.h"
  22 #include "interface.h"
  23 #include "interface-ip.h"
  24 #include "proto.h"
  25
  26 static struct avl_tree handlers;
  27
  28 enum {
  29         OPT_IPADDR,
  30         OPT_IP6ADDR,
  31         OPT_NETMASK,
  32         OPT_BROADCAST,
  33         OPT_GATEWAY,
  34         OPT_IP6GW,
  35         OPT_DNS,
  36         OPT_DNS_SEARCH,
  37         __OPT_MAX,
  38 };
  39
  40 static const struct blobmsg_policy proto_ip_attributes[__OPT_MAX] = {
  41         [OPT_IPADDR] = { .name = "ipaddr", .type = BLOBMSG_TYPE_ARRAY },
  42         [OPT_IP6ADDR] = { .name = "ip6addr", .type = BLOBMSG_TYPE_ARRAY },
  43         [OPT_NETMASK] = { .name = "netmask", .type = BLOBMSG_TYPE_STRING },
  44         [OPT_BROADCAST] = { .name = "broadcast", .type = BLOBMSG_TYPE_STRING },
  45         [OPT_GATEWAY] = { .name = "gateway", .type = BLOBMSG_TYPE_STRING },
  46         [OPT_IP6GW] = { .name = "ip6gw", .type = BLOBMSG_TYPE_STRING },
  47         [OPT_DNS] = { .name = "dns", .type = BLOBMSG_TYPE_ARRAY },
  48         [OPT_DNS_SEARCH] = { .name = "dns_search", .type = BLOBMSG_TYPE_ARRAY },
  49 };
  50
  51 static const union config_param_info proto_ip_attr_info[__OPT_MAX] = {
  52         [OPT_IPADDR] = { .type = BLOBMSG_TYPE_STRING },
  53         [OPT_IP6ADDR] = { .type = BLOBMSG_TYPE_STRING },
  54         [OPT_DNS] = { .type = BLOBMSG_TYPE_STRING },
  55 };
  56
  57 const struct config_param_list proto_ip_attr = {
  58         .n_params = __OPT_MAX,
  59         .params = proto_ip_attributes,
  60         .info = proto_ip_attr_info,
  61 };
  62
  63
  64 unsigned int
  65 parse_netmask_string(const char *str, bool v6)
  66 {
  67         struct in_addr addr;
  68         unsigned int ret;
  69         char *err = NULL;
  70
  71         if (!strchr(str, '.')) {
  72                 ret = strtoul(str, &err, 0);
  73                 if (err && *err)
  74                         goto error;
  75
  76                 return ret;
  77         }
  78
  79         if (v6)
  80                 goto error;
  81
  82         if (inet_aton(str, &addr) != 1)
  83                 goto error;
  84
  85         return 32 - fls(~(ntohl(addr.s_addr)));
  86
  87 error:
  88         return ~0;
  89 }
  90
  91 static bool
  92 split_netmask(char *str, unsigned int *netmask, bool v6)
  93 {
  94         char *delim = strchr(str, '/');
  95
  96         if (delim) {
  97                 *(delim++) = 0;
  98
  99                 *netmask = parse_netmask_string(delim, v6);
 100         }
 101         return true;
 102 }
 103
 104 static int
 105 parse_ip_and_netmask(int af, const char *str, void *addr, unsigned int *netmask)
 106 {
 107         char *astr = alloca(strlen(str) + 1);
 108
 109         strcpy(astr, str);
 110         if (!split_netmask(astr, netmask, af == AF_INET6))
 111                 return 0;
 112
 113         if (af == AF_INET6) {
 114                 if (*netmask > 128)
 115                         return 0;
 116         } else {
 117                 if (*netmask > 32)
 118                         return 0;
 119         }
 120
 121         return inet_pton(af, astr, addr);
 122 }
 123
 124 static struct device_addr *
 125 proto_parse_ip_addr_string(const char *str, bool v6, int mask)
 126 {
 127         struct device_addr *addr;
 128         int af = v6 ? AF_INET6 : AF_INET;
 129
 130         addr = calloc(1, sizeof(*addr));
 131         addr->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4;
 132         addr->mask = mask;
 133         if (!parse_ip_and_netmask(af, str, &addr->addr, &addr->mask)) {
 134                 free(addr);
 135                 return NULL;
 136         }
 137         return addr;
 138 }
 139
 140 static bool
 141 parse_addr(struct interface *iface, const char *str, bool v6, int mask,
 142            bool ext, uint32_t broadcast)
 143 {
 144         struct device_addr *addr;
 145
 146         addr = proto_parse_ip_addr_string(str, v6, mask);
 147         if (!addr) {
 148                 interface_add_error(iface, "proto", "INVALID_ADDRESS", &str, 1);
 149                 return false;
 150         }
 151
 152         if (broadcast)
 153                 addr->broadcast = broadcast;
 154
 155         if (ext)
 156                 addr->flags |= DEVADDR_EXTERNAL;
 157
 158         vlist_add(&iface->proto_ip.addr, &addr->node, &addr->flags);
 159         return true;
 160 }
 161
 162 static int
 163 parse_address_option(struct interface *iface, struct blob_attr *attr, bool v6,
 164                      int netmask, bool ext, uint32_t broadcast)
 165 {
 166         struct blob_attr *cur;
 167         int n_addr = 0;
 168         int rem;
 169
 170         blobmsg_for_each_attr(cur, attr, rem) {
 171                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 172                         return -1;
 173
 174                 n_addr++;
 175                 if (!parse_addr(iface, blobmsg_data(cur), v6, netmask, ext,
 176                                 broadcast))
 177                         return -1;
 178         }
 179
 180         return n_addr;
 181 }
 182
 183
 184 static bool
 185 parse_gateway_option(struct interface *iface, struct blob_attr *attr, bool v6)
 186 {
 187         struct device_route *route;
 188         const char *str = blobmsg_data(attr);
 189         int af = v6 ? AF_INET6 : AF_INET;
 190
 191         route = calloc(1, sizeof(*route));
 192         if (!inet_pton(af, str, &route->nexthop)) {
 193                 interface_add_error(iface, "proto", "INVALID_GATEWAY", &str, 1);
 194                 free(route);
 195                 return false;
 196         }
 197
 198         route->mask = 0;
 199         route->flags = (v6 ? DEVADDR_INET6 : DEVADDR_INET4);
 200         vlist_add(&iface->proto_ip.route, &route->node, &route->flags);
 201
 202         return true;
 203 }
 204
 205 int
 206 proto_apply_ip_settings(struct interface *iface, struct blob_attr *attr, bool ext)
 207 {
 208         struct blob_attr *tb[__OPT_MAX];
 209         struct blob_attr *cur;
 210         const char *error;
 211         unsigned int netmask = 32;
 212         int n_v4 = 0, n_v6 = 0;
 213         struct in_addr bcast = {};
 214
 215         blobmsg_parse(proto_ip_attributes, __OPT_MAX, tb, blob_data(attr), blob_len(attr));
 216
 217         if ((cur = tb[OPT_NETMASK])) {
 218                 netmask = parse_netmask_string(blobmsg_data(cur), false);
 219                 if (netmask > 32) {
 220                         error = "INVALID_NETMASK";
 221                         goto error;
 222                 }
 223         }
 224
 225         if ((cur = tb[OPT_BROADCAST])) {
 226                 if (!inet_pton(AF_INET, blobmsg_data(cur), &bcast)) {
 227                         error = "INVALID_BROADCAST";
 228                         goto error;
 229                 }
 230         }
 231
 232         if ((cur = tb[OPT_IPADDR]))
 233                 n_v4 = parse_address_option(iface, cur, false,
 234                         netmask, ext, bcast.s_addr);
 235
 236         if ((cur = tb[OPT_IP6ADDR]))
 237                 n_v6 = parse_address_option(iface, cur, true,
 238                         netmask, ext, 0);
 239
 240         if (!n_v4 && !n_v6) {
 241                 error = "NO_ADDRESS";
 242                 goto error;
 243         }
 244
 245         if (n_v4 < 0 || n_v6 < 0)
 246                 goto out;
 247
 248         if ((cur = tb[OPT_GATEWAY])) {
 249                 if (n_v4 && !parse_gateway_option(iface, cur, false))
 250                         goto out;
 251         }
 252
 253         if ((cur = tb[OPT_IP6GW])) {
 254                 if (n_v6 && !parse_gateway_option(iface, cur, true))
 255                         goto out;
 256         }
 257
 258         if ((cur = tb[OPT_DNS]))
 259                 interface_add_dns_server_list(&iface->proto_ip, cur);
 260
 261         if ((cur = tb[OPT_DNS_SEARCH]))
 262                 interface_add_dns_search_list(&iface->proto_ip, cur);
 263
 264         return 0;
 265
 266 error:
 267         interface_add_error(iface, "proto", error, NULL, 0);
 268 out:
 269         return -1;
 270 }
 271
 272 void add_proto_handler(struct proto_handler *p)
 273 {
 274         if (!handlers.comp)
 275                 avl_init(&handlers, avl_strcmp, false, NULL);
 276
 277         if (p->avl.key)
 278                 return;
 279
 280         p->avl.key = p->name;
 281         avl_insert(&handlers, &p->avl);
 282 }
 283
 284 static void
 285 default_proto_free(struct interface_proto_state *proto)
 286 {
 287         free(proto);
 288 }
 289
 290 static int
 291 invalid_proto_handler(struct interface_proto_state *proto,
 292                       enum interface_proto_cmd cmd, bool force)
 293 {
 294         return -1;
 295 }
 296
 297 static int
 298 no_proto_handler(struct interface_proto_state *proto,
 299                  enum interface_proto_cmd cmd, bool force)
 300 {
 301         return 0;
 302 }
 303
 304 static struct interface_proto_state *
 305 default_proto_attach(const struct proto_handler *h,
 306                      struct interface *iface, struct blob_attr *attr)
 307 {
 308         struct interface_proto_state *proto;
 309
 310         proto = calloc(1, sizeof(*proto));
 311         proto->free = default_proto_free;
 312         proto->cb = no_proto_handler;
 313
 314         return proto;
 315 }
 316
 317 static const struct proto_handler no_proto = {
 318         .name = "none",
 319         .flags = PROTO_FLAG_IMMEDIATE,
 320         .attach = default_proto_attach,
 321 };
 322
 323 static const struct proto_handler *
 324 get_proto_handler(const char *name)
 325 {
 326         struct proto_handler *proto;
 327
 328         if (!strcmp(name, "none"))
 329             return &no_proto;
 330
 331         if (!handlers.comp)
 332                 return NULL;
 333
 334         return avl_find_element(&handlers, name, proto, avl);
 335 }
 336
 337 void
 338 proto_init_interface(struct interface *iface, struct blob_attr *attr)
 339 {
 340         const struct proto_handler *proto = iface->proto_handler;
 341         struct interface_proto_state *state = NULL;
 342
 343         if (!proto)
 344                 proto = &no_proto;
 345
 346         state = proto->attach(proto, iface, attr);
 347         if (!state) {
 348                 state = no_proto.attach(&no_proto, iface, attr);
 349                 state->cb = invalid_proto_handler;
 350         }
 351
 352         state->handler = proto;
 353         interface_set_proto_state(iface, state);
 354 }
 355
 356 void
 357 proto_attach_interface(struct interface *iface, const char *proto_name)
 358 {
 359         const struct proto_handler *proto = &no_proto;
 360
 361         if (proto_name) {
 362                 proto = get_proto_handler(proto_name);
 363                 if (!proto) {
 364                         interface_add_error(iface, "proto", "INVALID_PROTO", NULL, 0);
 365                         proto = &no_proto;
 366                 }
 367         }
 368
 369         iface->proto_handler = proto;
 370 }
 371
 372 int
 373 interface_proto_event(struct interface_proto_state *proto,
 374                       enum interface_proto_cmd cmd, bool force)
 375 {
 376         enum interface_proto_event ev;
 377         int ret;
 378
 379         ret = proto->cb(proto, cmd, force);
 380         if (ret || !(proto->handler->flags & PROTO_FLAG_IMMEDIATE))
 381                 goto out;
 382
 383         switch(cmd) {
 384         case PROTO_CMD_SETUP:
 385                 ev = IFPEV_UP;
 386                 break;
 387         case PROTO_CMD_TEARDOWN:
 388                 ev = IFPEV_DOWN;
 389                 break;
 390         default:
 391                 return -EINVAL;
 392         }
 393         proto->proto_event(proto, ev);
 394
 395 out:
 396         return ret;
 397 }