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