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 "proto.h"
  11 #include "system.h"
  12
  13 enum {
  14         OPT_IPADDR,
  15         OPT_IP6ADDR,
  16         OPT_NETMASK,
  17         OPT_GATEWAY,
  18         OPT_IP6GW,
  19         __OPT_MAX,
  20 };
  21
  22 static const struct blobmsg_policy static_attrs[__OPT_MAX] = {
  23         [OPT_IPADDR] = { .name = "ipaddr", .type = BLOBMSG_TYPE_ARRAY },
  24         [OPT_IP6ADDR] = { .name = "ip6addr", .type = BLOBMSG_TYPE_ARRAY },
  25         [OPT_NETMASK] = { .name = "netmask", .type = BLOBMSG_TYPE_STRING },
  26         [OPT_GATEWAY] = { .name = "gateway", .type = BLOBMSG_TYPE_STRING },
  27         [OPT_IP6GW] = { .name = "ip6gw", .type = BLOBMSG_TYPE_STRING },
  28 };
  29
  30 static const union config_param_info static_attr_info[__OPT_MAX] = {
  31         [OPT_IPADDR] = { .type = BLOBMSG_TYPE_STRING },
  32         [OPT_IP6ADDR] = { .type = BLOBMSG_TYPE_STRING },
  33 };
  34
  35 static const struct config_param_list static_attr_list = {
  36         .n_params = __OPT_MAX,
  37         .params = static_attrs,
  38         .info = static_attr_info,
  39 };
  40
  41 struct static_proto_state {
  42         struct interface_proto_state proto;
  43
  44         struct blob_attr *config;
  45         struct interface *iface;
  46 };
  47
  48 static bool
  49 split_netmask(char *str, unsigned int *netmask)
  50 {
  51         char *delim, *err = NULL;
  52
  53         delim = strchr(str, '/');
  54         if (delim) {
  55                 *(delim++) = 0;
  56
  57                 *netmask = strtoul(delim, &err, 10);
  58                 if (err && *err)
  59                         return false;
  60         }
  61         return true;
  62 }
  63
  64 static int
  65 parse_ip_and_netmask(int af, const char *str, void *addr, unsigned int *netmask)
  66 {
  67         char *astr = alloca(strlen(str) + 1);
  68
  69         strcpy(astr, str);
  70         if (!split_netmask(astr, netmask))
  71                 return 0;
  72
  73         if (af == AF_INET6) {
  74                 if (*netmask > 128)
  75                         return 0;
  76         } else {
  77                 if (*netmask > 32)
  78                         return 0;
  79         }
  80
  81         return inet_pton(af, str, addr);
  82 }
  83
  84 static bool
  85 parse_addr(struct static_proto_state *state, const char *str, bool v6, int mask)
  86 {
  87         struct device_addr *addr;
  88         int af = v6 ? AF_INET6 : AF_INET;
  89
  90         addr = calloc(1, sizeof(*addr));
  91         addr->flags = v6 ? DEVADDR_INET6 : DEVADDR_INET4;
  92         addr->ctx = state;
  93         addr->mask = mask;
  94         if (!parse_ip_and_netmask(af, str, &addr->addr, &addr->mask)) {
  95                 interface_add_error(state->iface, "proto-static", "INVALID_ADDRESS", &str, 1);
  96                 free(addr);
  97                 return false;
  98         }
  99         interface_add_address(state->iface, addr);
 100         return true;
 101 }
 102
 103 static int
 104 parse_address_option(struct static_proto_state *state, struct blob_attr *attr, bool v6, int netmask)
 105 {
 106         struct blob_attr *cur;
 107         int n_addr = 0;
 108         int rem;
 109
 110         blobmsg_for_each_attr(cur, attr, rem) {
 111                 n_addr++;
 112                 if (!parse_addr(state, blobmsg_data(cur), v6, netmask))
 113                         return -1;
 114         }
 115
 116         return n_addr;
 117 }
 118
 119 static bool
 120 parse_gateway_option(struct static_proto_state *state, struct blob_attr *attr, bool v6)
 121 {
 122         struct device_route *route;
 123         const char *str = blobmsg_data(attr);
 124         int af = v6 ? AF_INET6 : AF_INET;
 125
 126         route = calloc(1, sizeof(*route));
 127         if (!inet_pton(af, str, &route->nexthop)) {
 128                 interface_add_error(state->iface, "proto-static",
 129                                 "INVALID_GATEWAY", &str, 1);
 130                 free(route);
 131                 return false;
 132         }
 133         route->mask = 0;
 134         route->flags = DEVADDR_DEVICE | (v6 ? DEVADDR_INET6 : DEVADDR_INET4);
 135         interface_add_route(state->iface, route);
 136
 137         return true;
 138 }
 139
 140 static bool
 141 static_proto_setup(struct static_proto_state *state)
 142 {
 143         struct blob_attr *tb[__OPT_MAX];
 144         struct in_addr ina;
 145         const char *error;
 146         int netmask = 32;
 147         int n_v4 = 0, n_v6 = 0;
 148
 149         blobmsg_parse(static_attrs, __OPT_MAX, tb, blob_data(state->config),
 150                 blob_len(state->config));
 151
 152         if (tb[OPT_NETMASK]) {
 153                 if (!inet_aton(blobmsg_data(tb[OPT_NETMASK]), &ina)) {
 154                         error = "INVALID_NETMASK";
 155                         goto error;
 156                 }
 157
 158                 netmask = 32 - fls(~(ntohl(ina.s_addr)));
 159         }
 160
 161         if (tb[OPT_IPADDR])
 162                 n_v4 = parse_address_option(state, tb[OPT_IPADDR], false, netmask);
 163
 164         if (tb[OPT_IP6ADDR])
 165                 n_v6 = parse_address_option(state, tb[OPT_IP6ADDR], true, netmask);
 166
 167         if (!n_v4 && !n_v6) {
 168                 error = "NO_ADDRESS";
 169                 goto error;
 170         }
 171
 172         if (n_v4 < 0 || n_v6 < 0)
 173                 goto out;
 174
 175         if (n_v4 && tb[OPT_GATEWAY]) {
 176                 if (!parse_gateway_option(state, tb[OPT_GATEWAY], false))
 177                         goto out;
 178         }
 179
 180         if (n_v6 && tb[OPT_IP6GW]) {
 181                 if (!parse_gateway_option(state, tb[OPT_IP6GW], true))
 182                         goto out;
 183         }
 184
 185         return true;
 186
 187 error:
 188         interface_add_error(state->iface, "proto-static", error, NULL, 0);
 189 out:
 190         return false;
 191 }
 192
 193 static int
 194 static_handler(struct interface_proto_state *proto,
 195                enum interface_proto_cmd cmd, bool force)
 196 {
 197         struct static_proto_state *state;
 198         int ret = 0;
 199
 200         state = container_of(proto, struct static_proto_state, proto);
 201
 202         switch (cmd) {
 203         case PROTO_CMD_SETUP:
 204                 if (static_proto_setup(state))
 205                         break;
 206
 207                 /* fall through */
 208         case PROTO_CMD_TEARDOWN:
 209                 interface_del_ctx_addr(state->iface, state);
 210                 break;
 211         }
 212         return ret;
 213 }
 214
 215 static void
 216 static_free(struct interface_proto_state *proto)
 217 {
 218         struct static_proto_state *state;
 219
 220         state = container_of(proto, struct static_proto_state, proto);
 221         free(state->config);
 222         free(state);
 223 }
 224
 225 struct interface_proto_state *
 226 static_attach(const struct proto_handler *h, struct interface *iface,
 227               struct blob_attr *attr)
 228 {
 229         struct static_proto_state *state;
 230
 231         state = calloc(1, sizeof(*state));
 232         if (!state)
 233                 return NULL;
 234
 235         state->iface = iface;
 236         state->config = malloc(blob_pad_len(attr));
 237         if (!state->config)
 238                 goto error;
 239
 240         memcpy(state->config, attr, blob_pad_len(attr));
 241         state->proto.free = static_free;
 242         state->proto.handler = static_handler;
 243         state->proto.flags = PROTO_FLAG_IMMEDIATE;
 244
 245         return &state->proto;
 246
 247 error:
 248         free(state);
 249         return NULL;
 250 }
 251
 252 static struct proto_handler static_proto = {
 253         .name = "static",
 254         .config_params = &static_attr_list,
 255         .attach = static_attach,
 256 };
 257
 258 static void __init
 259 static_proto_init(void)
 260 {
 261         add_proto_handler(&static_proto);
 262 }