proto.c

   1 #include <string.h>
   2 #include <stdlib.h>
   3 #include <stdio.h>
   4
   5 #include <arpa/inet.h>
   6 #include <netinet/in.h>
   7
   8 #include "netifd.h"
   9 #include "interface.h"
  10 #include "interface-ip.h"
  11 #include "proto.h"
  12
  13 static struct avl_tree handlers;
  14
  15 enum {
  16         OPT_IPADDR,
  17         OPT_IP6ADDR,
  18         OPT_NETMASK,
  19         OPT_BROADCAST,
  20         OPT_GATEWAY,
  21         OPT_IP6GW,
  22         OPT_DNS,
  23         OPT_DNS_SEARCH,
  24         __OPT_MAX,
  25 };
  26
  27 static const struct blobmsg_policy proto_ip_attributes[__OPT_MAX] = {
  28         [OPT_IPADDR] = { .name = "ipaddr", .type = BLOBMSG_TYPE_ARRAY },
  29         [OPT_IP6ADDR] = { .name = "ip6addr", .type = BLOBMSG_TYPE_ARRAY },
  30         [OPT_NETMASK] = { .name = "netmask", .type = BLOBMSG_TYPE_STRING },
  31         [OPT_BROADCAST] = { .name = "broadcast", .type = BLOBMSG_TYPE_STRING },
  32         [OPT_GATEWAY] = { .name = "gateway", .type = BLOBMSG_TYPE_STRING },
  33         [OPT_IP6GW] = { .name = "ip6gw", .type = BLOBMSG_TYPE_STRING },
  34         [OPT_DNS] = { .name = "dns", .type = BLOBMSG_TYPE_ARRAY },
  35         [OPT_DNS_SEARCH] = { .name = "dns_search", .type = BLOBMSG_TYPE_ARRAY },
  36 };
  37
  38 static const union config_param_info proto_ip_attr_info[__OPT_MAX] = {
  39         [OPT_IPADDR] = { .type = BLOBMSG_TYPE_STRING },
  40         [OPT_IP6ADDR] = { .type = BLOBMSG_TYPE_STRING },
  41         [OPT_DNS] = { .type = BLOBMSG_TYPE_STRING },
  42 };
  43
  44 const struct config_param_list proto_ip_attr = {
  45         .n_params = __OPT_MAX,
  46         .params = proto_ip_attributes,
  47         .info = proto_ip_attr_info,
  48 };
  49
  50
  51 unsigned int
  52 parse_netmask_string(const char *str, bool v6)
  53 {
  54         struct in_addr addr;
  55         unsigned int ret;
  56         char *err = NULL;
  57
  58         if (!strchr(str, '.')) {
  59                 ret = strtoul(str, &err, 0);
  60                 if (err && *err)
  61                         goto error;
  62
  63                 return ret;
  64         }
  65
  66         if (v6)
  67                 goto error;
  68
  69         if (inet_aton(str, &addr) != 1)
  70                 goto error;
  71
  72         return 32 - fls(~(ntohl(addr.s_addr)));
  73
  74 error:
  75         return ~0;
  76 }
  77
  78 static bool
  79 split_netmask(char *str, unsigned int *netmask, bool v6)
  80 {
  81         char *delim = strchr(str, '/');
  82
  83         if (delim) {
  84                 *(delim++) = 0;
  85
  86                 *netmask = parse_netmask_string(delim, v6);
  87         }
  88         return true;
  89 }
  90
  91 static int
  92 parse_ip_and_netmask(int af, const char *str, void *addr, unsigned int *netmask)
  93 {
  94         char *astr = alloca(strlen(str) + 1);
  95
  96         strcpy(astr, str);
  97         if (!split_netmask(astr, netmask, af == AF_INET6))
  98                 return 0;
  99
 100         if (af == AF_INET6) {
 101                 if (*netmask > 128)
 102                         return 0;
 103         } else {
 104                 if (*netmask > 32)
 105                         return 0;
 106         }
 107
 108         return inet_pton(af, astr, addr);
 109 }
 110
 111 static struct device_addr *
 112 proto_parse_ip_addr_string(const char *str, bool v6, int mask)
 113 {
 114         struct device_addr *addr;
 115         int af = v6 ? AF_INET6 : AF_INET;
 116
 117         addr = calloc(1, sizeof(*addr));
 118         addr->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4;
 119         addr->mask = mask;
 120         if (!parse_ip_and_netmask(af, str, &addr->addr, &addr->mask)) {
 121                 free(addr);
 122                 return NULL;
 123         }
 124         return addr;
 125 }
 126
 127 static bool
 128 parse_addr(struct interface *iface, const char *str, bool v6, int mask,
 129            bool ext, uint32_t broadcast)
 130 {
 131         struct device_addr *addr;
 132
 133         addr = proto_parse_ip_addr_string(str, v6, mask);
 134         if (!addr) {
 135                 interface_add_error(iface, "proto", "INVALID_ADDRESS", &str, 1);
 136                 return false;
 137         }
 138
 139         if (broadcast)
 140                 addr->broadcast = broadcast;
 141
 142         if (ext)
 143                 addr->flags |= DEVADDR_EXTERNAL;
 144
 145         vlist_add(&iface->proto_ip.addr, &addr->node);
 146         return true;
 147 }
 148
 149 static int
 150 parse_address_option(struct interface *iface, struct blob_attr *attr, bool v6,
 151                      int netmask, bool ext, uint32_t broadcast)
 152 {
 153         struct blob_attr *cur;
 154         int n_addr = 0;
 155         int rem;
 156
 157         blobmsg_for_each_attr(cur, attr, rem) {
 158                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 159                         return -1;
 160
 161                 n_addr++;
 162                 if (!parse_addr(iface, blobmsg_data(cur), v6, netmask, ext,
 163                                 broadcast))
 164                         return -1;
 165         }
 166
 167         return n_addr;
 168 }
 169
 170
 171 static bool
 172 parse_gateway_option(struct interface *iface, struct blob_attr *attr, bool v6)
 173 {
 174         struct device_route *route;
 175         const char *str = blobmsg_data(attr);
 176         int af = v6 ? AF_INET6 : AF_INET;
 177
 178         route = calloc(1, sizeof(*route));
 179         if (!inet_pton(af, str, &route->nexthop)) {
 180                 interface_add_error(iface, "proto", "INVALID_GATEWAY", &str, 1);
 181                 free(route);
 182                 return false;
 183         }
 184
 185         route->mask = 0;
 186         route->flags = DEVADDR_DEVICE | (v6 ? DEVADDR_INET6 : DEVADDR_INET4);
 187         vlist_add(&iface->proto_ip.route, &route->node);
 188
 189         return true;
 190 }
 191
 192 int
 193 proto_apply_ip_settings(struct interface *iface, struct blob_attr *attr, bool ext)
 194 {
 195         struct blob_attr *tb[__OPT_MAX];
 196         const char *error;
 197         unsigned int netmask = 32;
 198         int n_v4 = 0, n_v6 = 0;
 199         struct in_addr bcast = {};
 200
 201         blobmsg_parse(proto_ip_attributes, __OPT_MAX, tb, blob_data(attr), blob_len(attr));
 202
 203         if (tb[OPT_NETMASK]) {
 204                 netmask = parse_netmask_string(blobmsg_data(tb[OPT_NETMASK]), false);
 205                 if (netmask > 32) {
 206                         error = "INVALID_NETMASK";
 207                         goto error;
 208                 }
 209         }
 210
 211         if (tb[OPT_BROADCAST]) {
 212                 if (!inet_pton(AF_INET, blobmsg_data(tb[OPT_BROADCAST]), &bcast)) {
 213                         error = "INVALID_BROADCAST";
 214                         goto error;
 215                 }
 216         }
 217
 218         if (tb[OPT_IPADDR])
 219                 n_v4 = parse_address_option(iface, tb[OPT_IPADDR], false,
 220                         netmask, ext, bcast.s_addr);
 221
 222         if (tb[OPT_IP6ADDR])
 223                 n_v6 = parse_address_option(iface, tb[OPT_IP6ADDR], true,
 224                         netmask, ext, 0);
 225
 226         if (!n_v4 && !n_v6) {
 227                 error = "NO_ADDRESS";
 228                 goto error;
 229         }
 230
 231         if (n_v4 < 0 || n_v6 < 0)
 232                 goto out;
 233
 234         if (n_v4 && tb[OPT_GATEWAY]) {
 235                 if (!parse_gateway_option(iface, tb[OPT_GATEWAY], false))
 236                         goto out;
 237         }
 238
 239         if (n_v6 && tb[OPT_IP6GW]) {
 240                 if (!parse_gateway_option(iface, tb[OPT_IP6GW], true))
 241                         goto out;
 242         }
 243
 244         if (tb[OPT_DNS])
 245                 interface_add_dns_server_list(&iface->proto_ip, tb[OPT_DNS]);
 246
 247         if (tb[OPT_DNS_SEARCH])
 248                 interface_add_dns_search_list(&iface->proto_ip, tb[OPT_DNS_SEARCH]);
 249
 250         return 0;
 251
 252 error:
 253         interface_add_error(iface, "proto", error, NULL, 0);
 254 out:
 255         return -1;
 256 }
 257
 258 void add_proto_handler(struct proto_handler *p)
 259 {
 260         if (!handlers.comp)
 261                 avl_init(&handlers, avl_strcmp, false, NULL);
 262
 263         if (p->avl.key)
 264                 return;
 265
 266         p->avl.key = p->name;
 267         avl_insert(&handlers, &p->avl);
 268 }
 269
 270 static void
 271 default_proto_free(struct interface_proto_state *proto)
 272 {
 273         free(proto);
 274 }
 275
 276 static int
 277 invalid_proto_handler(struct interface_proto_state *proto,
 278                       enum interface_proto_cmd cmd, bool force)
 279 {
 280         return -1;
 281 }
 282
 283 static int
 284 no_proto_handler(struct interface_proto_state *proto,
 285                  enum interface_proto_cmd cmd, bool force)
 286 {
 287         return 0;
 288 }
 289
 290 static struct interface_proto_state *
 291 default_proto_attach(const struct proto_handler *h,
 292                      struct interface *iface, struct blob_attr *attr)
 293 {
 294         struct interface_proto_state *proto;
 295
 296         proto = calloc(1, sizeof(*proto));
 297         proto->free = default_proto_free;
 298         proto->cb = no_proto_handler;
 299
 300         return proto;
 301 }
 302
 303 static const struct proto_handler no_proto = {
 304         .name = "none",
 305         .flags = PROTO_FLAG_IMMEDIATE,
 306         .attach = default_proto_attach,
 307 };
 308
 309 static const struct proto_handler *
 310 get_proto_handler(const char *name)
 311 {
 312         struct proto_handler *proto;
 313
 314         if (!strcmp(name, "none"))
 315             return &no_proto;
 316
 317         if (!handlers.comp)
 318                 return NULL;
 319
 320         return avl_find_element(&handlers, name, proto, avl);
 321 }
 322
 323 void
 324 proto_init_interface(struct interface *iface, struct blob_attr *attr)
 325 {
 326         const struct proto_handler *proto = iface->proto_handler;
 327         struct interface_proto_state *state = NULL;
 328
 329         if (!proto)
 330                 proto = &no_proto;
 331
 332         state = proto->attach(proto, iface, attr);
 333         if (!state) {
 334                 state = no_proto.attach(&no_proto, iface, attr);
 335                 state->cb = invalid_proto_handler;
 336         }
 337
 338         state->handler = proto;
 339         interface_set_proto_state(iface, state);
 340 }
 341
 342 void
 343 proto_attach_interface(struct interface *iface, const char *proto_name)
 344 {
 345         const struct proto_handler *proto = &no_proto;
 346
 347         if (proto_name) {
 348                 proto = get_proto_handler(proto_name);
 349                 if (!proto) {
 350                         interface_add_error(iface, "proto", "INVALID_PROTO", NULL, 0);
 351                         proto = &no_proto;
 352                 }
 353         }
 354
 355         iface->proto_handler = proto;
 356 }
 357
 358 int
 359 interface_proto_event(struct interface_proto_state *proto,
 360                       enum interface_proto_cmd cmd, bool force)
 361 {
 362         enum interface_proto_event ev;
 363         int ret;
 364
 365         ret = proto->cb(proto, cmd, force);
 366         if (ret || !(proto->handler->flags & PROTO_FLAG_IMMEDIATE))
 367                 goto out;
 368
 369         switch(cmd) {
 370         case PROTO_CMD_SETUP:
 371                 ev = IFPEV_UP;
 372                 break;
 373         case PROTO_CMD_TEARDOWN:
 374                 ev = IFPEV_DOWN;
 375                 break;
 376         default:
 377                 return -EINVAL;
 378         }
 379         proto->proto_event(proto, ev);
 380
 381 out:
 382         return ret;
 383 }