proto-static.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 #include "system.h"
  13
  14 enum {
  15         OPT_IPADDR,
  16         OPT_IP6ADDR,
  17         OPT_NETMASK,
  18         OPT_GATEWAY,
  19         OPT_IP6GW,
  20         __OPT_MAX,
  21 };
  22
  23 static const struct blobmsg_policy static_attrs[__OPT_MAX] = {
  24         [OPT_IPADDR] = { .name = "ipaddr", .type = BLOBMSG_TYPE_ARRAY },
  25         [OPT_IP6ADDR] = { .name = "ip6addr", .type = BLOBMSG_TYPE_ARRAY },
  26         [OPT_NETMASK] = { .name = "netmask", .type = BLOBMSG_TYPE_STRING },
  27         [OPT_GATEWAY] = { .name = "gateway", .type = BLOBMSG_TYPE_STRING },
  28         [OPT_IP6GW] = { .name = "ip6gw", .type = BLOBMSG_TYPE_STRING },
  29 };
  30
  31 static const union config_param_info static_attr_info[__OPT_MAX] = {
  32         [OPT_IPADDR] = { .type = BLOBMSG_TYPE_STRING },
  33         [OPT_IP6ADDR] = { .type = BLOBMSG_TYPE_STRING },
  34 };
  35
  36 static const struct config_param_list static_attr_list = {
  37         .n_params = __OPT_MAX,
  38         .params = static_attrs,
  39         .info = static_attr_info,
  40 };
  41
  42 struct static_proto_state {
  43         struct interface_proto_state proto;
  44
  45         struct blob_attr *config;
  46         struct interface *iface;
  47 };
  48
  49 static bool
  50 split_netmask(char *str, unsigned int *netmask)
  51 {
  52         char *delim, *err = NULL;
  53
  54         delim = strchr(str, '/');
  55         if (delim) {
  56                 *(delim++) = 0;
  57
  58                 *netmask = strtoul(delim, &err, 10);
  59                 if (err && *err)
  60                         return false;
  61         }
  62         return true;
  63 }
  64
  65 static int
  66 parse_ip_and_netmask(int af, const char *str, void *addr, unsigned int *netmask)
  67 {
  68         char *astr = alloca(strlen(str) + 1);
  69
  70         strcpy(astr, str);
  71         if (!split_netmask(astr, netmask))
  72                 return 0;
  73
  74         if (af == AF_INET6) {
  75                 if (*netmask > 128)
  76                         return 0;
  77         } else {
  78                 if (*netmask > 32)
  79                         return 0;
  80         }
  81
  82         return inet_pton(af, str, addr);
  83 }
  84
  85 static bool
  86 parse_addr(struct static_proto_state *state, const char *str, bool v6, int mask)
  87 {
  88         struct device_addr *addr;
  89         int af = v6 ? AF_INET6 : AF_INET;
  90
  91         addr = calloc(1, sizeof(*addr));
  92         addr->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4;
  93         addr->ctx = state;
  94         addr->mask = mask;
  95         if (!parse_ip_and_netmask(af, str, &addr->addr, &addr->mask)) {
  96                 interface_add_error(state->iface, "proto-static", "INVALID_ADDRESS", &str, 1);
  97                 free(addr);
  98                 return false;
  99         }
 100         interface_add_address(state->iface, addr);
 101         return true;
 102 }
 103
 104 static int
 105 parse_address_option(struct static_proto_state *state, struct blob_attr *attr, bool v6, int netmask)
 106 {
 107         struct blob_attr *cur;
 108         int n_addr = 0;
 109         int rem;
 110
 111         blobmsg_for_each_attr(cur, attr, rem) {
 112                 n_addr++;
 113                 if (!parse_addr(state, blobmsg_data(cur), v6, netmask))
 114                         return -1;
 115         }
 116
 117         return n_addr;
 118 }
 119
 120 static bool
 121 parse_gateway_option(struct static_proto_state *state, struct blob_attr *attr, bool v6)
 122 {
 123         struct device_route *route;
 124         const char *str = blobmsg_data(attr);
 125         int af = v6 ? AF_INET6 : AF_INET;
 126
 127         route = calloc(1, sizeof(*route));
 128         if (!inet_pton(af, str, &route->nexthop)) {
 129                 interface_add_error(state->iface, "proto-static",
 130                                 "INVALID_GATEWAY", &str, 1);
 131                 free(route);
 132                 return false;
 133         }
 134         route->mask = 0;
 135         route->flags = DEVADDR_DEVICE | (v6 ? DEVADDR_INET6 : DEVADDR_INET4);
 136         interface_add_route(state->iface, route);
 137
 138         return true;
 139 }
 140
 141 static bool
 142 static_proto_setup(struct static_proto_state *state)
 143 {
 144         struct blob_attr *tb[__OPT_MAX];
 145         struct in_addr ina;
 146         const char *error;
 147         int netmask = 32;
 148         int n_v4 = 0, n_v6 = 0;
 149
 150         blobmsg_parse(static_attrs, __OPT_MAX, tb, blob_data(state->config),
 151                 blob_len(state->config));
 152
 153         if (tb[OPT_NETMASK]) {
 154                 if (!inet_aton(blobmsg_data(tb[OPT_NETMASK]), &ina)) {
 155                         error = "INVALID_NETMASK";
 156                         goto error;
 157                 }
 158
 159                 netmask = 32 - fls(~(ntohl(ina.s_addr)));
 160         }
 161
 162         if (tb[OPT_IPADDR])
 163                 n_v4 = parse_address_option(state, tb[OPT_IPADDR], false, netmask);
 164
 165         if (tb[OPT_IP6ADDR])
 166                 n_v6 = parse_address_option(state, tb[OPT_IP6ADDR], true, netmask);
 167
 168         if (!n_v4 && !n_v6) {
 169                 error = "NO_ADDRESS";
 170                 goto error;
 171         }
 172
 173         if (n_v4 < 0 || n_v6 < 0)
 174                 goto out;
 175
 176         if (n_v4 && tb[OPT_GATEWAY]) {
 177                 if (!parse_gateway_option(state, tb[OPT_GATEWAY], false))
 178                         goto out;
 179         }
 180
 181         if (n_v6 && tb[OPT_IP6GW]) {
 182                 if (!parse_gateway_option(state, tb[OPT_IP6GW], true))
 183                         goto out;
 184         }
 185
 186         return true;
 187
 188 error:
 189         interface_add_error(state->iface, "proto-static", error, NULL, 0);
 190 out:
 191         return false;
 192 }
 193
 194 static int
 195 static_handler(struct interface_proto_state *proto,
 196                enum interface_proto_cmd cmd, bool force)
 197 {
 198         struct static_proto_state *state;
 199         int ret = 0;
 200
 201         state = container_of(proto, struct static_proto_state, proto);
 202
 203         switch (cmd) {
 204         case PROTO_CMD_SETUP:
 205                 if (static_proto_setup(state))
 206                         break;
 207
 208                 /* fall through */
 209         case PROTO_CMD_TEARDOWN:
 210                 interface_del_ctx_addr(state->iface, state);
 211                 break;
 212         }
 213         return ret;
 214 }
 215
 216 static void
 217 static_free(struct interface_proto_state *proto)
 218 {
 219         struct static_proto_state *state;
 220
 221         state = container_of(proto, struct static_proto_state, proto);
 222         free(state->config);
 223         free(state);
 224 }
 225
 226 struct interface_proto_state *
 227 static_attach(const struct proto_handler *h, struct interface *iface,
 228               struct blob_attr *attr)
 229 {
 230         struct static_proto_state *state;
 231
 232         state = calloc(1, sizeof(*state));
 233         if (!state)
 234                 return NULL;
 235
 236         state->iface = iface;
 237         state->config = malloc(blob_pad_len(attr));
 238         if (!state->config)
 239                 goto error;
 240
 241         memcpy(state->config, attr, blob_pad_len(attr));
 242         state->proto.free = static_free;
 243         state->proto.handler = static_handler;
 244         state->proto.flags = PROTO_FLAG_IMMEDIATE;
 245
 246         return &state->proto;
 247
 248 error:
 249         free(state);
 250         return NULL;
 251 }
 252
 253 static struct proto_handler static_proto = {
 254         .name = "static",
 255         .config_params = &static_attr_list,
 256         .attach = static_attach,
 257 };
 258
 259 static void __init
 260 static_proto_init(void)
 261 {
 262         add_proto_handler(&static_proto);
 263 }