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 #define min(a, b) (((a) < (b)) ? (a) : (b))
  30 #define max(a, b) (((a) > (b)) ? (a) : (b))
  31
  32 // RFC 6106 defines this router advertisement option
  33 #define ND_OPT_ROUTE_INFO 24
  34 #define ND_OPT_RECURSIVE_DNS 25
  35 #define ND_OPT_DNS_SEARCH 31
  36
  37 #define INFINITE_VALID(x) ((x) == 0)
  38
  39 #define _unused __attribute__((unused))
  40 #define _packed __attribute__((packed))
  41
  42 #define ALL_IPV6_NODES "ff02::1"
  43 #define ALL_IPV6_ROUTERS "ff02::2"
  44
  45 #define NTP_SUBOPTION_SRV_ADDR 1
  46 #define NTP_SUBOPTION_MC_ADDR 2
  47 #define NTP_SUBOPTION_SRV_FQDN 3
  48 #define IPV6_ADDR_LEN 16
  49
  50 #define IN6_IS_ADDR_ULA(a) (((a)->s6_addr32[0] & htonl(0xfe000000)) == htonl(0xfc000000))
  51
  52 #define ADDR_MATCH_PIO_FILTER(_addr, iface) (odhcpd_bmemcmp(&(_addr)->addr, \
  53                                                             &(iface)->pio_filter_addr, \
  54                                                             (iface)->pio_filter_length) != 0 || \
  55                                              (_addr)->prefix < (iface)->pio_filter_length)
  56
  57 struct interface;
  58 struct nl_sock;
  59 extern struct vlist_tree leases;
  60 extern struct config config;
  61
  62 struct odhcpd_event {
  63         struct uloop_fd uloop;
  64         void (*handle_dgram)(void *addr, void *data, size_t len,
  65                         struct interface *iface, void *dest_addr);
  66         void (*handle_error)(struct odhcpd_event *e, int error);
  67         void (*recv_msgs)(struct odhcpd_event *e);
  68 };
  69
  70 typedef int (*send_reply_cb_t)(const void *buf, size_t len,
  71                                const struct sockaddr *dest, socklen_t dest_len,
  72                                void *opaque);
  73
  74 typedef void (*dhcpv6_binding_cb_handler_t)(struct in6_addr *addr, int prefix,
  75                                             uint32_t pref, uint32_t valid,
  76                                             void *arg);
  77
  78 union if_addr {
  79         struct in_addr in;
  80         struct in6_addr in6;
  81 };
  82
  83 struct netevent_handler_info {
  84         struct interface *iface;
  85         union {
  86                 struct {
  87                         union if_addr dst;
  88                         uint8_t dst_len;
  89                         union if_addr gateway;
  90                 } rt;
  91                 struct {
  92                         union if_addr dst;
  93                         uint16_t state;
  94                         uint8_t flags;
  95                 } neigh;
  96                 struct {
  97                         struct odhcpd_ipaddr *addrs;
  98                         size_t len;
  99                 } addrs_old;
 100                 union if_addr addr;
 101         };
 102 };
 103
 104 enum netevents {
 105         NETEV_IFINDEX_CHANGE,
 106         NETEV_ADDR_ADD,
 107         NETEV_ADDR_DEL,
 108         NETEV_ADDRLIST_CHANGE,
 109         NETEV_ADDR6_ADD,
 110         NETEV_ADDR6_DEL,
 111         NETEV_ADDR6LIST_CHANGE,
 112         NETEV_ROUTE6_ADD,
 113         NETEV_ROUTE6_DEL,
 114         NETEV_NEIGH6_ADD,
 115         NETEV_NEIGH6_DEL,
 116 };
 117
 118 struct netevent_handler {
 119         struct list_head head;
 120         void (*cb) (unsigned long event, struct netevent_handler_info *info);
 121 };
 122
 123 struct odhcpd_ipaddr {
 124         union if_addr addr;
 125         uint8_t prefix;
 126         uint32_t preferred;
 127         uint32_t valid;
 128
 129         union {
 130                 /* ipv6 only */
 131                 struct {
 132                         uint8_t dprefix;
 133                         uint8_t invalid_advertisements;
 134                         bool tentative;
 135                 };
 136
 137                 /* ipv4 only */
 138                 struct in_addr broadcast;
 139         };
 140 };
 141
 142 enum odhcpd_mode {
 143         MODE_DISABLED,
 144         MODE_SERVER,
 145         MODE_RELAY,
 146         MODE_HYBRID
 147 };
 148
 149
 150 enum odhcpd_assignment_flags {
 151         OAF_TENTATIVE           = (1 << 0),
 152         OAF_BOUND               = (1 << 1),
 153         OAF_STATIC              = (1 << 2),
 154         OAF_BROKEN_HOSTNAME     = (1 << 3),
 155         OAF_DHCPV4              = (1 << 4),
 156         OAF_DHCPV6_NA           = (1 << 5),
 157         OAF_DHCPV6_PD           = (1 << 6),
 158 };
 159
 160 struct config {
 161         bool legacy;
 162         bool main_dhcpv4;
 163         char *dhcp_cb;
 164         char *dhcp_statefile;
 165         int log_level;
 166 };
 167
 168
 169 struct lease {
 170         struct vlist_node node;
 171         struct list_head assignments;
 172         uint32_t ipaddr;
 173         uint64_t hostid;
 174         struct ether_addr mac;
 175         uint16_t duid_len;
 176         uint8_t *duid;
 177         uint32_t leasetime;
 178         char *hostname;
 179 };
 180
 181 enum {
 182         LEASE_ATTR_IP,
 183         LEASE_ATTR_MAC,
 184         LEASE_ATTR_DUID,
 185         LEASE_ATTR_HOSTID,
 186         LEASE_ATTR_LEASETIME,
 187         LEASE_ATTR_NAME,
 188         LEASE_ATTR_MAX
 189 };
 190
 191 struct odhcpd_ref_ip;
 192
 193 struct dhcp_assignment {
 194         struct list_head head;
 195         struct list_head lease_list;
 196
 197         void (*dhcp_free_cb)(struct dhcp_assignment *a);
 198
 199         struct interface *iface;
 200         struct lease *lease;
 201
 202         struct sockaddr_in6 peer;
 203         time_t valid_until;
 204         time_t preferred_until;
 205
 206 #define fr_timer        reconf_timer
 207         struct uloop_timeout reconf_timer;
 208 #define accept_fr_nonce accept_reconf
 209         bool accept_reconf;
 210 #define fr_cnt          reconf_cnt
 211         int reconf_cnt;
 212         uint8_t key[16];
 213         struct odhcpd_ref_ip *fr_ip;
 214
 215         uint32_t addr;
 216         union {
 217                 uint64_t assigned_host_id;
 218                 uint32_t assigned_subnet_id;
 219         };
 220         uint32_t iaid;
 221         uint8_t length; // length == 128 -> IA_NA, length <= 64 -> IA_PD
 222
 223         struct odhcpd_ipaddr *managed;
 224         ssize_t managed_size;
 225         struct ustream_fd managed_sock;
 226
 227         unsigned int flags;
 228         uint32_t leasetime;
 229         char *hostname;
 230         char *reqopts;
 231 #define hwaddr          mac
 232         uint8_t mac[6];
 233
 234         uint16_t clid_len;
 235         uint8_t clid_data[];
 236 };
 237
 238
 239 struct interface {
 240         struct avl_node avl;
 241
 242         int ifflags;
 243         int ifindex;
 244         char *ifname;
 245         const char *name;
 246
 247         // IPv6 runtime data
 248         struct odhcpd_ipaddr *addr6;
 249         size_t addr6_len;
 250         struct odhcpd_ipaddr *invalid_addr6;
 251         size_t invalid_addr6_len;
 252
 253         // RA runtime data
 254         struct odhcpd_event router_event;
 255         struct uloop_timeout timer_rs;
 256         uint32_t ra_sent;
 257
 258         // DHCPv6 runtime data
 259         struct odhcpd_event dhcpv6_event;
 260         struct list_head ia_assignments;
 261
 262         // NDP runtime data
 263         struct odhcpd_event ndp_event;
 264         int ndp_ping_fd;
 265
 266         // IPv4 runtime data
 267         struct odhcpd_ipaddr *addr4;
 268         size_t addr4_len;
 269
 270         // DHCPv4 runtime data
 271         struct odhcpd_event dhcpv4_event;
 272         struct list_head dhcpv4_assignments;
 273         struct list_head dhcpv4_fr_ips;
 274
 275         // Managed PD
 276         char dhcpv6_pd_manager[128];
 277         struct in6_addr dhcpv6_pd_cer;
 278
 279         // Services
 280         enum odhcpd_mode ra;
 281         enum odhcpd_mode dhcpv6;
 282         enum odhcpd_mode ndp;
 283         enum odhcpd_mode dhcpv4;
 284
 285         // Config
 286         bool inuse;
 287         bool external;
 288         bool master;
 289         bool ignore;
 290         bool always_rewrite_dns;
 291         bool dns_service;
 292
 293         // NDP
 294         int learn_routes;
 295
 296         // RA
 297         uint8_t ra_flags;
 298         bool ra_slaac;
 299         bool ra_not_onlink;
 300         bool ra_advrouter;
 301         bool ra_useleasetime;
 302         bool ra_dns;
 303         bool no_dynamic_dhcp;
 304         bool have_link_local;
 305         uint8_t pio_filter_length;
 306         struct in6_addr pio_filter_addr;
 307         int default_router;
 308         int route_preference;
 309         int ra_maxinterval;
 310         int ra_mininterval;
 311         int ra_lifetime;
 312         uint32_t ra_reachabletime;
 313         uint32_t ra_retranstime;
 314         uint32_t ra_hoplimit;
 315         int ra_mtu;
 316         uint32_t preferred_lifetime;
 317
 318         // DHCP
 319         uint32_t dhcp_leasetime;
 320
 321         // DHCPv4
 322         struct in_addr dhcpv4_start;
 323         struct in_addr dhcpv4_end;
 324         struct in_addr dhcpv4_start_ip;
 325         struct in_addr dhcpv4_end_ip;
 326         struct in_addr dhcpv4_local;
 327         struct in_addr dhcpv4_bcast;
 328         struct in_addr dhcpv4_mask;
 329         struct in_addr *dhcpv4_router;
 330         size_t dhcpv4_router_cnt;
 331         struct in_addr *dhcpv4_dns;
 332         size_t dhcpv4_dns_cnt;
 333         bool dhcpv4_forcereconf;
 334
 335         // DNS
 336         struct in6_addr *dns;
 337         size_t dns_cnt;
 338         uint8_t *search;
 339         size_t search_len;
 340
 341         // DHCPV6
 342         void *dhcpv6_raw;
 343         size_t dhcpv6_raw_len;
 344         bool dhcpv6_assignall;
 345         bool dhcpv6_pd;
 346         bool dhcpv6_na;
 347         uint32_t dhcpv6_hostid_len;
 348
 349         char *upstream;
 350         size_t upstream_len;
 351
 352         char *filter_class;
 353
 354         // NTP
 355         struct in_addr *dhcpv4_ntp;
 356         size_t dhcpv4_ntp_cnt;
 357         uint8_t *dhcpv6_ntp;
 358         uint16_t dhcpv6_ntp_len;
 359         size_t dhcpv6_ntp_cnt;
 360
 361         // SNTP
 362         struct in6_addr *dhcpv6_sntp;
 363         size_t dhcpv6_sntp_cnt;
 364 };
 365
 366 extern struct avl_tree interfaces;
 367 extern const struct blobmsg_policy lease_attrs[LEASE_ATTR_MAX];
 368
 369 inline static void free_assignment(struct dhcp_assignment *a)
 370 {
 371         list_del(&a->head);
 372         list_del(&a->lease_list);
 373
 374         if (a->dhcp_free_cb)
 375                 a->dhcp_free_cb(a);
 376
 377         free(a->hostname);
 378         free(a->reqopts);
 379         free(a);
 380 }
 381
 382 inline static struct dhcp_assignment *alloc_assignment(size_t extra_len)
 383 {
 384         struct dhcp_assignment *a = calloc(1, sizeof(*a) + extra_len);
 385
 386         if (!a)
 387                 return NULL;
 388
 389         INIT_LIST_HEAD(&a->head);
 390         INIT_LIST_HEAD(&a->lease_list);
 391
 392         return a;
 393 }
 394
 395 // Exported main functions
 396 int odhcpd_register(struct odhcpd_event *event);
 397 int odhcpd_deregister(struct odhcpd_event *event);
 398 void odhcpd_process(struct odhcpd_event *event);
 399
 400 ssize_t odhcpd_send(int socket, struct sockaddr_in6 *dest,
 401                 struct iovec *iov, size_t iov_len,
 402                 const struct interface *iface);
 403 int odhcpd_get_interface_dns_addr(const struct interface *iface,
 404                 struct in6_addr *addr);
 405 int odhcpd_get_interface_config(const char *ifname, const char *what);
 406 int odhcpd_get_mac(const struct interface *iface, uint8_t mac[6]);
 407 int odhcpd_get_flags(const struct interface *iface);
 408 struct interface* odhcpd_get_interface_by_index(int ifindex);
 409 int odhcpd_urandom(void *data, size_t len);
 410
 411 void odhcpd_run(void);
 412 time_t odhcpd_time(void);
 413 ssize_t odhcpd_unhexlify(uint8_t *dst, size_t len, const char *src);
 414 void odhcpd_hexlify(char *dst, const uint8_t *src, size_t len);
 415 const char *odhcpd_print_mac(const uint8_t *mac, const size_t len);
 416
 417 int odhcpd_bmemcmp(const void *av, const void *bv, size_t bits);
 418 void odhcpd_bmemcpy(void *av, const void *bv, size_t bits);
 419
 420 int odhcpd_netmask2bitlen(bool v6, void *mask);
 421 bool odhcpd_bitlen2netmask(bool v6, unsigned int bits, void *mask);
 422 bool odhcpd_valid_hostname(const char *name);
 423
 424 int config_parse_interface(void *data, size_t len, const char *iname, bool overwrite);
 425 struct lease *config_find_lease_by_duid(const uint8_t *duid, const uint16_t len);
 426 struct lease *config_find_lease_by_mac(const uint8_t *mac);
 427 struct lease *config_find_lease_by_hostid(const uint64_t hostid);
 428 struct lease *config_find_lease_by_ipaddr(const uint32_t ipaddr);
 429 int set_lease_from_blobmsg(struct blob_attr *ba);
 430
 431 #ifdef WITH_UBUS
 432 int ubus_init(void);
 433 const char* ubus_get_ifname(const char *name);
 434 void ubus_apply_network(void);
 435 bool ubus_has_prefix(const char *name, const char *ifname);
 436 void ubus_bcast_dhcp_event(const char *type, const uint8_t *mac, const size_t mac_len,
 437                 const struct in_addr *addr, const char *name, const char *interface);
 438 #endif
 439
 440 ssize_t dhcpv6_ia_handle_IAs(uint8_t *buf, size_t buflen, struct interface *iface,
 441                 const struct sockaddr_in6 *addr, const void *data, const uint8_t *end);
 442 int dhcpv6_ia_init(void);
 443 int dhcpv6_ia_setup_interface(struct interface *iface, bool enable);
 444 void dhcpv6_ia_enum_addrs(struct interface *iface, struct dhcp_assignment *c, time_t now,
 445                                 dhcpv6_binding_cb_handler_t func, void *arg);
 446 void dhcpv6_ia_write_statefile(void);
 447
 448 int netlink_add_netevent_handler(struct netevent_handler *hdlr);
 449 ssize_t netlink_get_interface_addrs(const int ifindex, bool v6,
 450                 struct odhcpd_ipaddr **addrs);
 451 int netlink_get_interface_proxy_neigh(int ifindex, const struct in6_addr *addr);
 452 int netlink_setup_route(const struct in6_addr *addr, const int prefixlen,
 453                 const int ifindex, const struct in6_addr *gw,
 454                 const uint32_t metric, const bool add);
 455 int netlink_setup_proxy_neigh(const struct in6_addr *addr,
 456                 const int ifindex, const bool add);
 457 int netlink_setup_addr(struct odhcpd_ipaddr *addr,
 458                 const int ifindex, const bool v6, const bool add);
 459 void netlink_dump_neigh_table(const bool proxy);
 460 void netlink_dump_addr_table(const bool v6);
 461
 462 // Exported module initializers
 463 int netlink_init(void);
 464 int router_init(void);
 465 int dhcpv6_init(void);
 466 int ndp_init(void);
 467 #ifdef DHCPV4_SUPPORT
 468 int dhcpv4_init(void);
 469
 470 int dhcpv4_setup_interface(struct interface *iface, bool enable);
 471 void dhcpv4_handle_msg(void *addr, void *data, size_t len,
 472                        struct interface *iface, _unused void *dest_addr,
 473                        send_reply_cb_t send_reply, void *opaque);
 474 #endif
 475 int router_setup_interface(struct interface *iface, bool enable);
 476 int dhcpv6_setup_interface(struct interface *iface, bool enable);
 477 int ndp_setup_interface(struct interface *iface, bool enable);
 478
 479 void odhcpd_reload(void);