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
  48 struct odhcpd_event {
  49         struct uloop_fd uloop;
  50         void (*handle_dgram)(void *addr, void *data, size_t len,
  51                         struct interface *iface, void *dest_addr);
  52         void (*handle_error)(struct odhcpd_event *e, int error);
  53         void (*recv_msgs)(struct odhcpd_event *e);
  54 };
  55
  56 typedef void (*dhcpv6_binding_cb_handler_t)(struct in6_addr *addr, int prefix,
  57                                             uint32_t pref, uint32_t valid,
  58                                             void *arg);
  59
  60 union if_addr {
  61         struct in_addr in;
  62         struct in6_addr in6;
  63 };
  64
  65 struct netevent_handler_info {
  66         struct interface *iface;
  67         union {
  68                 struct {
  69                         union if_addr dst;
  70                         uint8_t dst_len;
  71                         union if_addr gateway;
  72                 } rt;
  73                 struct {
  74                         union if_addr dst;
  75                         uint16_t state;
  76                         uint8_t flags;
  77                 } neigh;
  78                 struct {
  79                         struct odhcpd_ipaddr *addrs;
  80                         size_t len;
  81                 } addrs_old;
  82                 union if_addr addr;
  83         };
  84 };
  85
  86 enum netevents {
  87         NETEV_IFINDEX_CHANGE,
  88         NETEV_ADDR_ADD,
  89         NETEV_ADDR_DEL,
  90         NETEV_ADDRLIST_CHANGE,
  91         NETEV_ADDR6_ADD,
  92         NETEV_ADDR6_DEL,
  93         NETEV_ADDR6LIST_CHANGE,
  94         NETEV_ROUTE6_ADD,
  95         NETEV_ROUTE6_DEL,
  96         NETEV_NEIGH6_ADD,
  97         NETEV_NEIGH6_DEL,
  98 };
  99
 100 struct netevent_handler {
 101         struct list_head head;
 102         void (*cb) (unsigned long event, struct netevent_handler_info *info);
 103 };
 104
 105 struct odhcpd_ipaddr {
 106         union if_addr addr;
 107         uint8_t prefix;
 108         uint32_t preferred;
 109         uint32_t valid;
 110
 111         /* ipv6 only */
 112         uint8_t dprefix;
 113
 114         /* ipv4 only */
 115         struct in_addr broadcast;
 116 };
 117
 118 enum odhcpd_mode {
 119         MODE_DISABLED,
 120         MODE_SERVER,
 121         MODE_RELAY,
 122         MODE_HYBRID
 123 };
 124
 125
 126 enum odhcpd_assignment_flags {
 127         OAF_TENTATIVE           = (1 << 0),
 128         OAF_BOUND               = (1 << 1),
 129         OAF_STATIC              = (1 << 2),
 130         OAF_BROKEN_HOSTNAME     = (1 << 3),
 131         OAF_DHCPV4              = (1 << 4),
 132         OAF_DHCPV6              = (1 << 5),
 133 };
 134
 135 struct config {
 136         bool legacy;
 137         bool main_dhcpv4;
 138         char *dhcp_cb;
 139         char *dhcp_statefile;
 140         int log_level;
 141 } config;
 142
 143
 144 struct lease {
 145         struct vlist_node node;
 146         struct list_head assignments;
 147         uint32_t ipaddr;
 148         uint32_t hostid;
 149         struct ether_addr mac;
 150         uint16_t duid_len;
 151         uint8_t *duid;
 152         uint32_t leasetime;
 153         char *hostname;
 154 };
 155
 156
 157 struct odhcpd_ref_ip;
 158
 159 struct dhcp_assignment {
 160         struct list_head head;
 161         struct list_head lease_list;
 162
 163         void (*dhcp_free_cb)(struct dhcp_assignment *a);
 164
 165         struct interface *iface;
 166         struct lease *lease;
 167
 168         struct sockaddr_in6 peer;
 169         time_t valid_until;
 170
 171 #define fr_timer        reconf_timer
 172         struct uloop_timeout reconf_timer;
 173 #define accept_fr_nonce accept_reconf
 174         bool accept_reconf;
 175 #define fr_cnt          reconf_cnt
 176         int reconf_cnt;
 177         uint8_t key[16];
 178         struct odhcpd_ref_ip *fr_ip;
 179
 180         uint32_t addr;
 181         uint32_t assigned;
 182         uint32_t iaid;
 183         uint8_t length; // length == 128 -> IA_NA, length <= 64 -> IA_PD
 184
 185         struct odhcpd_ipaddr *managed;
 186         ssize_t managed_size;
 187         struct ustream_fd managed_sock;
 188
 189         unsigned int flags;
 190         uint32_t leasetime;
 191         char *hostname;
 192         char *reqopts;
 193 #define hwaddr          mac
 194         uint8_t mac[6];
 195
 196         uint16_t clid_len;
 197         uint8_t clid_data[];
 198 };
 199
 200
 201 struct interface {
 202         struct avl_node avl;
 203
 204         int ifindex;
 205         char *ifname;
 206         const char *name;
 207
 208         // IPv6 runtime data
 209         struct odhcpd_ipaddr *addr6;
 210         size_t addr6_len;
 211
 212         // RA runtime data
 213         struct odhcpd_event router_event;
 214         struct uloop_timeout timer_rs;
 215
 216         // DHCPv6 runtime data
 217         struct odhcpd_event dhcpv6_event;
 218         struct list_head ia_assignments;
 219
 220         // NDP runtime data
 221         struct odhcpd_event ndp_event;
 222         int ndp_ping_fd;
 223
 224         // IPv4 runtime data
 225         struct odhcpd_ipaddr *addr4;
 226         size_t addr4_len;
 227
 228         // DHCPv4 runtime data
 229         struct odhcpd_event dhcpv4_event;
 230         struct list_head dhcpv4_assignments;
 231         struct list_head dhcpv4_fr_ips;
 232
 233         // Managed PD
 234         char dhcpv6_pd_manager[128];
 235         struct in6_addr dhcpv6_pd_cer;
 236
 237         // Services
 238         enum odhcpd_mode ra;
 239         enum odhcpd_mode dhcpv6;
 240         enum odhcpd_mode ndp;
 241         enum odhcpd_mode dhcpv4;
 242
 243         // Config
 244         bool inuse;
 245         bool external;
 246         bool master;
 247         bool ignore;
 248         bool always_rewrite_dns;
 249         bool ra_not_onlink;
 250         bool ra_advrouter;
 251         bool ra_useleasetime;
 252         bool ra_dns;
 253         bool no_dynamic_dhcp;
 254         uint8_t pio_filter_length;
 255         struct in6_addr pio_filter_addr;
 256
 257         // RA
 258         int learn_routes;
 259         int default_router;
 260         int ra_managed;
 261         int route_preference;
 262         int ra_maxinterval;
 263         int ra_mininterval;
 264         int ra_lifetime;
 265         uint32_t ra_reachabletime;
 266         uint32_t ra_retranstime;
 267         uint32_t ra_hoplimit;
 268         int ra_mtu;
 269
 270         // DHCPv4
 271         struct in_addr dhcpv4_start;
 272         struct in_addr dhcpv4_end;
 273         struct in_addr dhcpv4_start_ip;
 274         struct in_addr dhcpv4_end_ip;
 275         struct in_addr dhcpv4_local;
 276         struct in_addr dhcpv4_bcast;
 277         struct in_addr dhcpv4_mask;
 278         struct in_addr *dhcpv4_router;
 279         size_t dhcpv4_router_cnt;
 280         struct in_addr *dhcpv4_dns;
 281         size_t dhcpv4_dns_cnt;
 282         uint32_t dhcpv4_leasetime;
 283         bool dhcpv4_forcereconf;
 284
 285         // DNS
 286         struct in6_addr *dns;
 287         size_t dns_cnt;
 288         uint8_t *search;
 289         size_t search_len;
 290
 291         // DHCPV6
 292         void *dhcpv6_raw;
 293         size_t dhcpv6_raw_len;
 294         bool dhcpv6_assignall;
 295         bool dhcpv6_pd;
 296         bool dhcpv6_na;
 297
 298         char *upstream;
 299         size_t upstream_len;
 300
 301         char *filter_class;
 302 };
 303
 304 extern struct avl_tree interfaces;
 305
 306 #define RA_MANAGED_NO_MFLAG     0
 307 #define RA_MANAGED_MFLAG        1
 308 #define RA_MANAGED_NO_AFLAG     2
 309
 310 inline static void free_assignment(struct dhcp_assignment *a)
 311 {
 312         if (a->head.next)
 313                 list_del(&a->head);
 314
 315         if (a->lease_list.next)
 316                 list_del(&a->lease_list);
 317
 318         if (a->dhcp_free_cb)
 319                 a->dhcp_free_cb(a);
 320
 321         free(a->hostname);
 322         free(a->reqopts);
 323         free(a);
 324 }
 325
 326 // Exported main functions
 327 int odhcpd_register(struct odhcpd_event *event);
 328 int odhcpd_deregister(struct odhcpd_event *event);
 329 void odhcpd_process(struct odhcpd_event *event);
 330
 331 ssize_t odhcpd_send(int socket, struct sockaddr_in6 *dest,
 332                 struct iovec *iov, size_t iov_len,
 333                 const struct interface *iface);
 334 int odhcpd_get_interface_dns_addr(const struct interface *iface,
 335                 struct in6_addr *addr);
 336 int odhcpd_get_interface_config(const char *ifname, const char *what);
 337 int odhcpd_get_mac(const struct interface *iface, uint8_t mac[6]);
 338 struct interface* odhcpd_get_interface_by_index(int ifindex);
 339 int odhcpd_urandom(void *data, size_t len);
 340
 341 void odhcpd_run(void);
 342 time_t odhcpd_time(void);
 343 ssize_t odhcpd_unhexlify(uint8_t *dst, size_t len, const char *src);
 344 void odhcpd_hexlify(char *dst, const uint8_t *src, size_t len);
 345 const char *odhcpd_print_mac(const uint8_t *mac, const size_t len);
 346
 347 int odhcpd_bmemcmp(const void *av, const void *bv, size_t bits);
 348 void odhcpd_bmemcpy(void *av, const void *bv, size_t bits);
 349
 350 int odhcpd_netmask2bitlen(bool v6, void *mask);
 351 bool odhcpd_bitlen2netmask(bool v6, unsigned int bits, void *mask);
 352 bool odhcpd_valid_hostname(const char *name);
 353
 354 int config_parse_interface(void *data, size_t len, const char *iname, bool overwrite);
 355 struct lease *config_find_lease_by_duid(const uint8_t *duid, const uint16_t len);
 356 struct lease *config_find_lease_by_mac(const uint8_t *mac);
 357 struct lease *config_find_lease_by_hostid(const uint32_t hostid);
 358 struct lease *config_find_lease_by_ipaddr(const uint32_t ipaddr);
 359
 360 #ifdef WITH_UBUS
 361 int ubus_init(void);
 362 const char* ubus_get_ifname(const char *name);
 363 void ubus_apply_network(void);
 364 bool ubus_has_prefix(const char *name, const char *ifname);
 365 void ubus_bcast_dhcp_event(const char *type, const uint8_t *mac, const size_t mac_len,
 366                 const struct in_addr *addr, const char *name, const char *interface);
 367 #endif
 368
 369 ssize_t dhcpv6_ia_handle_IAs(uint8_t *buf, size_t buflen, struct interface *iface,
 370                 const struct sockaddr_in6 *addr, const void *data, const uint8_t *end);
 371 int dhcpv6_ia_init(void);
 372 int dhcpv6_ia_setup_interface(struct interface *iface, bool enable);
 373 void dhcpv6_ia_enum_addrs(struct interface *iface, struct dhcp_assignment *c, time_t now,
 374                                 dhcpv6_binding_cb_handler_t func, void *arg);
 375 void dhcpv6_ia_write_statefile(void);
 376
 377 int netlink_add_netevent_handler(struct netevent_handler *hdlr);
 378 ssize_t netlink_get_interface_addrs(const int ifindex, bool v6,
 379                 struct odhcpd_ipaddr **addrs);
 380 int netlink_setup_route(const struct in6_addr *addr, const int prefixlen,
 381                 const int ifindex, const struct in6_addr *gw,
 382                 const uint32_t metric, const bool add);
 383 int netlink_setup_proxy_neigh(const struct in6_addr *addr,
 384                 const int ifindex, const bool add);
 385 int netlink_setup_addr(struct odhcpd_ipaddr *addr,
 386                 const int ifindex, const bool v6, const bool add);
 387 void netlink_dump_neigh_table(const bool proxy);
 388 void netlink_dump_addr_table(const bool v6);
 389
 390 // Exported module initializers
 391 int netlink_init(void);
 392 int router_init(void);
 393 int dhcpv6_init(void);
 394 int ndp_init(void);
 395 #ifdef DHCPV4_SUPPORT
 396 int dhcpv4_init(void);
 397
 398 int dhcpv4_setup_interface(struct interface *iface, bool enable);
 399 #endif
 400 int router_setup_interface(struct interface *iface, bool enable);
 401 int dhcpv6_setup_interface(struct interface *iface, bool enable);
 402 int ndp_setup_interface(struct interface *iface, bool enable);
 403
 404 void odhcpd_reload(void);