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