src/odhcpd.h

   1 /**
   2  * Copyright (C) 2012-2013 Steven Barth <steven@midlink.org>
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License v2 as published by
   6  * the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  */
  14
  15 #pragma once
  16 #include <netinet/in.h>
  17 #include <netinet/icmp6.h>
  18 #include <netinet/ether.h>
  19 #include <stdbool.h>
  20 #include <syslog.h>
  21
  22 #include <libubox/blobmsg.h>
  23 #include <libubox/list.h>
  24 #include <libubox/uloop.h>
  25 #include <libubox/avl.h>
  26 #include <libubox/ustream.h>
  27 #include <libubox/vlist.h>
  28
  29 // RFC 6106 defines this router advertisement option
  30 #define ND_OPT_ROUTE_INFO 24
  31 #define ND_OPT_RECURSIVE_DNS 25
  32 #define ND_OPT_DNS_SEARCH 31
  33
  34 #define INFINITE_VALID(x) ((x) == 0)
  35
  36 #define _unused __attribute__((unused))
  37 #define _packed __attribute__((packed))
  38
  39 #define ALL_IPV6_NODES "ff02::1"
  40 #define ALL_IPV6_ROUTERS "ff02::2"
  41
  42 #define IN6_IS_ADDR_ULA(a) (((a)->s6_addr32[0] & htonl(0xfe000000)) == htonl(0xfc000000))
  43
  44 struct interface;
  45 struct nl_sock;
  46 extern struct vlist_tree leases;
  47 extern struct config config;
  48
  49 struct odhcpd_event {
  50         struct uloop_fd uloop;
  51         void (*handle_dgram)(void *addr, void *data, size_t len,
  52                         struct interface *iface, void *dest_addr);
  53         void (*handle_error)(struct odhcpd_event *e, int error);
  54         void (*recv_msgs)(struct odhcpd_event *e);
  55 };
  56
  57 typedef void (*dhcpv6_binding_cb_handler_t)(struct in6_addr *addr, int prefix,
  58                                             uint32_t pref, uint32_t valid,
  59                                             void *arg);
  60
  61 union if_addr {
  62         struct in_addr in;
  63         struct in6_addr in6;
  64 };
  65
  66 struct netevent_handler_info {
  67         struct interface *iface;
  68         union {
  69                 struct {
  70                         union if_addr dst;
  71                         uint8_t dst_len;
  72                         union if_addr gateway;
  73                 } rt;
  74                 struct {
  75                         union if_addr dst;
  76                         uint16_t state;
  77                         uint8_t flags;
  78                 } neigh;
  79                 struct {
  80                         struct odhcpd_ipaddr *addrs;
  81                         size_t len;
  82                 } addrs_old;
  83                 union if_addr addr;
  84         };
  85 };
  86
  87 enum netevents {
  88         NETEV_IFINDEX_CHANGE,
  89         NETEV_ADDR_ADD,
  90         NETEV_ADDR_DEL,
  91         NETEV_ADDRLIST_CHANGE,
  92         NETEV_ADDR6_ADD,
  93         NETEV_ADDR6_DEL,
  94         NETEV_ADDR6LIST_CHANGE,
  95         NETEV_ROUTE6_ADD,
  96         NETEV_ROUTE6_DEL,
  97         NETEV_NEIGH6_ADD,
  98         NETEV_NEIGH6_DEL,
  99 };
 100
 101 struct netevent_handler {
 102         struct list_head head;
 103         void (*cb) (unsigned long event, struct netevent_handler_info *info);
 104 };
 105
 106 struct odhcpd_ipaddr {
 107         union if_addr addr;
 108         uint8_t prefix;
 109         uint32_t preferred;
 110         uint32_t valid;
 111
 112         /* ipv6 only */
 113         uint8_t dprefix;
 114
 115         /* ipv4 only */
 116         struct in_addr broadcast;
 117 };
 118
 119 enum odhcpd_mode {
 120         MODE_DISABLED,
 121         MODE_SERVER,
 122         MODE_RELAY,
 123         MODE_HYBRID
 124 };
 125
 126
 127 enum odhcpd_assignment_flags {
 128         OAF_TENTATIVE           = (1 << 0),
 129         OAF_BOUND               = (1 << 1),
 130         OAF_STATIC              = (1 << 2),
 131         OAF_BROKEN_HOSTNAME     = (1 << 3),
 132         OAF_DHCPV4              = (1 << 4),
 133         OAF_DHCPV6_NA           = (1 << 5),
 134         OAF_DHCPV6_PD           = (1 << 6),
 135 };
 136
 137 struct config {
 138         bool legacy;
 139         bool main_dhcpv4;
 140         char *dhcp_cb;
 141         char *dhcp_statefile;
 142         int log_level;
 143 };
 144
 145
 146 struct lease {
 147         struct vlist_node node;
 148         struct list_head assignments;
 149         uint32_t ipaddr;
 150         uint32_t hostid;
 151         struct ether_addr mac;
 152         uint16_t duid_len;
 153         uint8_t *duid;
 154         uint32_t leasetime;
 155         char *hostname;
 156 };
 157
 158
 159 struct odhcpd_ref_ip;
 160
 161 struct dhcp_assignment {
 162         struct list_head head;
 163         struct list_head lease_list;
 164
 165         void (*dhcp_free_cb)(struct dhcp_assignment *a);
 166
 167         struct interface *iface;
 168         struct lease *lease;
 169
 170         struct sockaddr_in6 peer;
 171         time_t valid_until;
 172
 173 #define fr_timer        reconf_timer
 174         struct uloop_timeout reconf_timer;
 175 #define accept_fr_nonce accept_reconf
 176         bool accept_reconf;
 177 #define fr_cnt          reconf_cnt
 178         int reconf_cnt;
 179         uint8_t key[16];
 180         struct odhcpd_ref_ip *fr_ip;
 181
 182         uint32_t addr;
 183         uint32_t assigned;
 184         uint32_t iaid;
 185         uint8_t length; // length == 128 -> IA_NA, length <= 64 -> IA_PD
 186
 187         struct odhcpd_ipaddr *managed;
 188         ssize_t managed_size;
 189         struct ustream_fd managed_sock;
 190
 191         unsigned int flags;
 192         uint32_t leasetime;
 193         char *hostname;
 194         char *reqopts;
 195 #define hwaddr          mac
 196         uint8_t mac[6];
 197
 198         uint16_t clid_len;
 199         uint8_t clid_data[];
 200 };
 201
 202
 203 struct interface {
 204         struct avl_node avl;
 205
 206         int ifindex;
 207         char *ifname;
 208         const char *name;
 209
 210         // IPv6 runtime data
 211         struct odhcpd_ipaddr *addr6;
 212         size_t addr6_len;
 213
 214         // RA runtime data
 215         struct odhcpd_event router_event;
 216         struct uloop_timeout timer_rs;
 217         uint32_t ra_sent;
 218
 219         // DHCPv6 runtime data
 220         struct odhcpd_event dhcpv6_event;
 221         struct list_head ia_assignments;
 222
 223         // NDP runtime data
 224         struct odhcpd_event ndp_event;
 225         int ndp_ping_fd;
 226
 227         // IPv4 runtime data
 228         struct odhcpd_ipaddr *addr4;
 229         size_t addr4_len;
 230
 231         // DHCPv4 runtime data
 232         struct odhcpd_event dhcpv4_event;
 233         struct list_head dhcpv4_assignments;
 234         struct list_head dhcpv4_fr_ips;
 235
 236         // Managed PD
 237         char dhcpv6_pd_manager[128];
 238         struct in6_addr dhcpv6_pd_cer;
 239
 240         // Services
 241         enum odhcpd_mode ra;
 242         enum odhcpd_mode dhcpv6;
 243         enum odhcpd_mode ndp;
 244         enum odhcpd_mode dhcpv4;
 245
 246         // Config
 247         bool inuse;
 248         bool external;
 249         bool master;
 250         bool ignore;
 251         bool always_rewrite_dns;
 252
 253         // NDP
 254         int learn_routes;
 255
 256         // RA
 257         uint8_t ra_flags;
 258         bool ra_slaac;
 259         bool ra_not_onlink;
 260         bool ra_advrouter;
 261         bool ra_useleasetime;
 262         bool ra_dns;
 263         bool no_dynamic_dhcp;
 264         uint8_t pio_filter_length;
 265         struct in6_addr pio_filter_addr;
 266         int default_router;
 267         int route_preference;
 268         int ra_maxinterval;
 269         int ra_mininterval;
 270         int ra_lifetime;
 271         uint32_t ra_reachabletime;
 272         uint32_t ra_retranstime;
 273         uint32_t ra_hoplimit;
 274         int ra_mtu;
 275
 276         // DHCP
 277         uint32_t dhcp_leasetime;
 278
 279         // DHCPv4
 280         struct in_addr dhcpv4_start;
 281         struct in_addr dhcpv4_end;
 282         struct in_addr dhcpv4_start_ip;
 283         struct in_addr dhcpv4_end_ip;
 284         struct in_addr dhcpv4_local;
 285         struct in_addr dhcpv4_bcast;
 286         struct in_addr dhcpv4_mask;
 287         struct in_addr *dhcpv4_router;
 288         size_t dhcpv4_router_cnt;
 289         struct in_addr *dhcpv4_dns;
 290         size_t dhcpv4_dns_cnt;
 291         bool dhcpv4_forcereconf;
 292
 293         // DNS
 294         struct in6_addr *dns;
 295         size_t dns_cnt;
 296         uint8_t *search;
 297         size_t search_len;
 298
 299         // DHCPV6
 300         void *dhcpv6_raw;
 301         size_t dhcpv6_raw_len;
 302         bool dhcpv6_assignall;
 303         bool dhcpv6_pd;
 304         bool dhcpv6_na;
 305
 306         char *upstream;
 307         size_t upstream_len;
 308
 309         char *filter_class;
 310 };
 311
 312 extern struct avl_tree interfaces;
 313
 314 inline static void free_assignment(struct dhcp_assignment *a)
 315 {
 316         list_del(&a->head);
 317         list_del(&a->lease_list);
 318
 319         if (a->dhcp_free_cb)
 320                 a->dhcp_free_cb(a);
 321
 322         free(a->hostname);
 323         free(a->reqopts);
 324         free(a);
 325 }
 326
 327 inline static struct dhcp_assignment *alloc_assignment(size_t extra_len)
 328 {
 329         struct dhcp_assignment *a = calloc(1, sizeof(*a) + extra_len);
 330
 331         if (!a)
 332                 return NULL;
 333
 334         INIT_LIST_HEAD(&a->head);
 335         INIT_LIST_HEAD(&a->lease_list);
 336
 337         return a;
 338 }
 339
 340 // Exported main functions
 341 int odhcpd_register(struct odhcpd_event *event);
 342 int odhcpd_deregister(struct odhcpd_event *event);
 343 void odhcpd_process(struct odhcpd_event *event);
 344
 345 ssize_t odhcpd_send(int socket, struct sockaddr_in6 *dest,
 346                 struct iovec *iov, size_t iov_len,
 347                 const struct interface *iface);
 348 int odhcpd_get_interface_dns_addr(const struct interface *iface,
 349                 struct in6_addr *addr);
 350 int odhcpd_get_interface_config(const char *ifname, const char *what);
 351 int odhcpd_get_mac(const struct interface *iface, uint8_t mac[6]);
 352 struct interface* odhcpd_get_interface_by_index(int ifindex);
 353 int odhcpd_urandom(void *data, size_t len);
 354
 355 void odhcpd_run(void);
 356 time_t odhcpd_time(void);
 357 ssize_t odhcpd_unhexlify(uint8_t *dst, size_t len, const char *src);
 358 void odhcpd_hexlify(char *dst, const uint8_t *src, size_t len);
 359 const char *odhcpd_print_mac(const uint8_t *mac, const size_t len);
 360
 361 int odhcpd_bmemcmp(const void *av, const void *bv, size_t bits);
 362 void odhcpd_bmemcpy(void *av, const void *bv, size_t bits);
 363
 364 int odhcpd_netmask2bitlen(bool v6, void *mask);
 365 bool odhcpd_bitlen2netmask(bool v6, unsigned int bits, void *mask);
 366 bool odhcpd_valid_hostname(const char *name);
 367
 368 int config_parse_interface(void *data, size_t len, const char *iname, bool overwrite);
 369 struct lease *config_find_lease_by_duid(const uint8_t *duid, const uint16_t len);
 370 struct lease *config_find_lease_by_mac(const uint8_t *mac);
 371 struct lease *config_find_lease_by_hostid(const uint32_t hostid);
 372 struct lease *config_find_lease_by_ipaddr(const uint32_t ipaddr);
 373
 374 #ifdef WITH_UBUS
 375 int ubus_init(void);
 376 const char* ubus_get_ifname(const char *name);
 377 void ubus_apply_network(void);
 378 bool ubus_has_prefix(const char *name, const char *ifname);
 379 void ubus_bcast_dhcp_event(const char *type, const uint8_t *mac, const size_t mac_len,
 380                 const struct in_addr *addr, const char *name, const char *interface);
 381 #endif
 382
 383 ssize_t dhcpv6_ia_handle_IAs(uint8_t *buf, size_t buflen, struct interface *iface,
 384                 const struct sockaddr_in6 *addr, const void *data, const uint8_t *end);
 385 int dhcpv6_ia_init(void);
 386 int dhcpv6_ia_setup_interface(struct interface *iface, bool enable);
 387 void dhcpv6_ia_enum_addrs(struct interface *iface, struct dhcp_assignment *c, time_t now,
 388                                 dhcpv6_binding_cb_handler_t func, void *arg);
 389 void dhcpv6_ia_write_statefile(void);
 390
 391 int netlink_add_netevent_handler(struct netevent_handler *hdlr);
 392 ssize_t netlink_get_interface_addrs(const int ifindex, bool v6,
 393                 struct odhcpd_ipaddr **addrs);
 394 int netlink_get_interface_proxy_neigh(int ifindex, const struct in6_addr *addr);
 395 int netlink_setup_route(const struct in6_addr *addr, const int prefixlen,
 396                 const int ifindex, const struct in6_addr *gw,
 397                 const uint32_t metric, const bool add);
 398 int netlink_setup_proxy_neigh(const struct in6_addr *addr,
 399                 const int ifindex, const bool add);
 400 int netlink_setup_addr(struct odhcpd_ipaddr *addr,
 401                 const int ifindex, const bool v6, const bool add);
 402 void netlink_dump_neigh_table(const bool proxy);
 403 void netlink_dump_addr_table(const bool v6);
 404
 405 // Exported module initializers
 406 int netlink_init(void);
 407 int router_init(void);
 408 int dhcpv6_init(void);
 409 int ndp_init(void);
 410 #ifdef DHCPV4_SUPPORT
 411 int dhcpv4_init(void);
 412
 413 int dhcpv4_setup_interface(struct interface *iface, bool enable);
 414 #endif
 415 int router_setup_interface(struct interface *iface, bool enable);
 416 int dhcpv6_setup_interface(struct interface *iface, bool enable);
 417 int ndp_setup_interface(struct interface *iface, bool enable);
 418
 419 void odhcpd_reload(void);