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 };
  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 interface_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 interface_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 interface_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 int
 141 proto_apply_static_settings(struct interface_proto_state *state, struct blob_attr *attr)
 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(attr), blob_len(attr));
 150
 151         if (tb[OPT_NETMASK]) {
 152                 if (!inet_aton(blobmsg_data(tb[OPT_NETMASK]), &ina)) {
 153                         error = "INVALID_NETMASK";
 154                         goto error;
 155                 }
 156
 157                 netmask = 32 - fls(~(ntohl(ina.s_addr)));
 158         }
 159
 160         if (tb[OPT_IPADDR])
 161                 n_v4 = parse_address_option(state, tb[OPT_IPADDR], false, netmask);
 162
 163         if (tb[OPT_IP6ADDR])
 164                 n_v6 = parse_address_option(state, tb[OPT_IP6ADDR], true, netmask);
 165
 166         if (!n_v4 && !n_v6) {
 167                 error = "NO_ADDRESS";
 168                 goto error;
 169         }
 170
 171         if (n_v4 < 0 || n_v6 < 0)
 172                 goto out;
 173
 174         if (n_v4 && tb[OPT_GATEWAY]) {
 175                 if (!parse_gateway_option(state, tb[OPT_GATEWAY], false))
 176                         goto out;
 177         }
 178
 179         if (n_v6 && tb[OPT_IP6GW]) {
 180                 if (!parse_gateway_option(state, tb[OPT_IP6GW], true))
 181                         goto out;
 182         }
 183
 184         return 0;
 185
 186 error:
 187         interface_add_error(state->iface, "proto-static", error, NULL, 0);
 188 out:
 189         return -1;
 190 }
 191
 192 static bool
 193 static_proto_setup(struct static_proto_state *state)
 194 {
 195         return proto_apply_static_settings(&state->proto, state->config) == 0;
 196 }
 197
 198 static int
 199 static_handler(struct interface_proto_state *proto,
 200                enum interface_proto_cmd cmd, bool force)
 201 {
 202         struct static_proto_state *state;
 203         int ret = 0;
 204
 205         state = container_of(proto, struct static_proto_state, proto);
 206
 207         switch (cmd) {
 208         case PROTO_CMD_SETUP:
 209                 if (static_proto_setup(state))
 210                         break;
 211
 212                 /* fall through */
 213         case PROTO_CMD_TEARDOWN:
 214                 interface_del_ctx_addr(state->proto.iface, proto);
 215                 break;
 216         }
 217         return ret;
 218 }
 219
 220 static void
 221 static_free(struct interface_proto_state *proto)
 222 {
 223         struct static_proto_state *state;
 224
 225         state = container_of(proto, struct static_proto_state, proto);
 226         free(state->config);
 227         free(state);
 228 }
 229
 230 struct interface_proto_state *
 231 static_attach(const struct proto_handler *h, struct interface *iface,
 232               struct blob_attr *attr)
 233 {
 234         struct static_proto_state *state;
 235
 236         state = calloc(1, sizeof(*state));
 237         if (!state)
 238                 return NULL;
 239
 240         state->config = malloc(blob_pad_len(attr));
 241         if (!state->config)
 242                 goto error;
 243
 244         memcpy(state->config, attr, blob_pad_len(attr));
 245         state->proto.free = static_free;
 246         state->proto.handler = static_handler;
 247         state->proto.flags = PROTO_FLAG_IMMEDIATE;
 248
 249         return &state->proto;
 250
 251 error:
 252         free(state);
 253         return NULL;
 254 }
 255
 256 static struct proto_handler static_proto = {
 257         .name = "static",
 258         .config_params = &static_attr_list,
 259         .attach = static_attach,
 260 };
 261
 262 static void __init
 263 static_proto_init(void)
 264 {
 265         add_proto_handler(&static_proto);
 266 }