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