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 static 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,
 127            bool ext, uint32_t broadcast)
 128 {
 129         struct device_addr *addr;
 130
 131         addr = proto_parse_ip_addr_string(str, v6, mask);
 132         if (!addr) {
 133                 interface_add_error(iface, "proto", "INVALID_ADDRESS", &str, 1);
 134                 return false;
 135         }
 136
 137         if (broadcast)
 138                 addr->broadcast = broadcast;
 139
 140         if (ext)
 141                 addr->flags |= DEVADDR_EXTERNAL;
 142
 143         vlist_add(&iface->proto_ip.addr, &addr->node);
 144         return true;
 145 }
 146
 147 static int
 148 parse_address_option(struct interface *iface, struct blob_attr *attr, bool v6,
 149                      int netmask, bool ext, uint32_t broadcast)
 150 {
 151         struct blob_attr *cur;
 152         int n_addr = 0;
 153         int rem;
 154
 155         blobmsg_for_each_attr(cur, attr, rem) {
 156                 if (blobmsg_type(cur) != BLOBMSG_TYPE_STRING)
 157                         return -1;
 158
 159                 n_addr++;
 160                 if (!parse_addr(iface, blobmsg_data(cur), v6, netmask, ext,
 161                                 broadcast))
 162                         return -1;
 163         }
 164
 165         return n_addr;
 166 }
 167
 168
 169 static bool
 170 parse_gateway_option(struct interface *iface, struct blob_attr *attr, bool v6)
 171 {
 172         struct device_route *route;
 173         const char *str = blobmsg_data(attr);
 174         int af = v6 ? AF_INET6 : AF_INET;
 175
 176         route = calloc(1, sizeof(*route));
 177         if (!inet_pton(af, str, &route->nexthop)) {
 178                 interface_add_error(iface, "proto", "INVALID_GATEWAY", &str, 1);
 179                 free(route);
 180                 return false;
 181         }
 182
 183         route->mask = 0;
 184         route->flags = DEVADDR_DEVICE | (v6 ? DEVADDR_INET6 : DEVADDR_INET4);
 185         vlist_add(&iface->proto_ip.route, &route->node);
 186
 187         return true;
 188 }
 189
 190 int
 191 proto_apply_ip_settings(struct interface *iface, struct blob_attr *attr, bool ext)
 192 {
 193         struct blob_attr *tb[__OPT_MAX];
 194         const char *error;
 195         unsigned int netmask = 32;
 196         int n_v4 = 0, n_v6 = 0;
 197         uint32_t broadcast = 0;
 198
 199         blobmsg_parse(proto_ip_attributes, __OPT_MAX, tb, blob_data(attr), blob_len(attr));
 200
 201         if (tb[OPT_NETMASK]) {
 202                 netmask = parse_netmask_string(blobmsg_data(tb[OPT_NETMASK]), false);
 203                 if (netmask > 32) {
 204                         error = "INVALID_NETMASK";
 205                         goto error;
 206                 }
 207         }
 208
 209         if (tb[OPT_IPADDR])
 210                 n_v4 = parse_address_option(iface, tb[OPT_IPADDR], false,
 211                         netmask, ext, broadcast);
 212
 213         if (tb[OPT_IP6ADDR])
 214                 n_v6 = parse_address_option(iface, tb[OPT_IP6ADDR], true,
 215                         netmask, ext, 0);
 216
 217         if (!n_v4 && !n_v6) {
 218                 error = "NO_ADDRESS";
 219                 goto error;
 220         }
 221
 222         if (n_v4 < 0 || n_v6 < 0)
 223                 goto out;
 224
 225         if (n_v4 && tb[OPT_GATEWAY]) {
 226                 if (!parse_gateway_option(iface, tb[OPT_GATEWAY], false))
 227                         goto out;
 228         }
 229
 230         if (n_v6 && tb[OPT_IP6GW]) {
 231                 if (!parse_gateway_option(iface, tb[OPT_IP6GW], true))
 232                         goto out;
 233         }
 234
 235         if (tb[OPT_DNS])
 236                 interface_add_dns_server_list(&iface->proto_ip, tb[OPT_DNS]);
 237
 238         if (tb[OPT_DNS_SEARCH])
 239                 interface_add_dns_search_list(&iface->proto_ip, tb[OPT_DNS_SEARCH]);
 240
 241         return 0;
 242
 243 error:
 244         interface_add_error(iface, "proto", error, NULL, 0);
 245 out:
 246         return -1;
 247 }
 248
 249 void add_proto_handler(struct proto_handler *p)
 250 {
 251         if (!handlers.comp)
 252                 avl_init(&handlers, avl_strcmp, false, NULL);
 253
 254         if (p->avl.key)
 255                 return;
 256
 257         p->avl.key = p->name;
 258         avl_insert(&handlers, &p->avl);
 259 }
 260
 261 static void
 262 default_proto_free(struct interface_proto_state *proto)
 263 {
 264         free(proto);
 265 }
 266
 267 static int
 268 invalid_proto_handler(struct interface_proto_state *proto,
 269                       enum interface_proto_cmd cmd, bool force)
 270 {
 271         return -1;
 272 }
 273
 274 static int
 275 no_proto_handler(struct interface_proto_state *proto,
 276                  enum interface_proto_cmd cmd, bool force)
 277 {
 278         return 0;
 279 }
 280
 281 static struct interface_proto_state *
 282 default_proto_attach(const struct proto_handler *h,
 283                      struct interface *iface, struct blob_attr *attr)
 284 {
 285         struct interface_proto_state *proto;
 286
 287         proto = calloc(1, sizeof(*proto));
 288         proto->free = default_proto_free;
 289         proto->cb = no_proto_handler;
 290
 291         return proto;
 292 }
 293
 294 static const struct proto_handler no_proto = {
 295         .name = "none",
 296         .flags = PROTO_FLAG_IMMEDIATE,
 297         .attach = default_proto_attach,
 298 };
 299
 300 static const struct proto_handler *
 301 get_proto_handler(const char *name)
 302 {
 303         struct proto_handler *proto;
 304
 305         if (!strcmp(name, "none"))
 306             return &no_proto;
 307
 308         if (!handlers.comp)
 309                 return NULL;
 310
 311         return avl_find_element(&handlers, name, proto, avl);
 312 }
 313
 314 void
 315 proto_init_interface(struct interface *iface, struct blob_attr *attr)
 316 {
 317         const struct proto_handler *proto = iface->proto_handler;
 318         struct interface_proto_state *state = NULL;
 319
 320         if (!proto)
 321                 proto = &no_proto;
 322
 323         state = proto->attach(proto, iface, attr);
 324         if (!state) {
 325                 state = no_proto.attach(&no_proto, iface, attr);
 326                 state->cb = invalid_proto_handler;
 327         }
 328
 329         state->handler = proto;
 330         interface_set_proto_state(iface, state);
 331 }
 332
 333 void
 334 proto_attach_interface(struct interface *iface, const char *proto_name)
 335 {
 336         const struct proto_handler *proto = &no_proto;
 337
 338         if (proto_name) {
 339                 proto = get_proto_handler(proto_name);
 340                 if (!proto) {
 341                         interface_add_error(iface, "proto", "INVALID_PROTO", NULL, 0);
 342                         proto = &no_proto;
 343                 }
 344         }
 345
 346         iface->proto_handler = proto;
 347 }
 348
 349 int
 350 interface_proto_event(struct interface_proto_state *proto,
 351                       enum interface_proto_cmd cmd, bool force)
 352 {
 353         enum interface_proto_event ev;
 354         int ret;
 355
 356         ret = proto->cb(proto, cmd, force);
 357         if (ret || !(proto->handler->flags & PROTO_FLAG_IMMEDIATE))
 358                 goto out;
 359
 360         switch(cmd) {
 361         case PROTO_CMD_SETUP:
 362                 ev = IFPEV_UP;
 363                 break;
 364         case PROTO_CMD_TEARDOWN:
 365                 ev = IFPEV_DOWN;
 366                 break;
 367         default:
 368                 return -EINVAL;
 369         }
 370         proto->proto_event(proto, ev);
 371
 372 out:
 373         return ret;
 374 }