1 /* 2 * xfrd.h - XFR (transfer) Daemon header file. Coordinates SOA updates. 3 * 4 * Copyright (c) 2001-2006, NLnet Labs. All rights reserved. 5 * 6 * See LICENSE for the license. 7 * 8 */ 9 10 #ifndef XFRD_H 11 #define XFRD_H 12 13 #ifndef USE_MINI_EVENT 14 # ifdef HAVE_EVENT_H 15 # include <event.h> 16 # else 17 # include <event2/event.h> 18 # include "event2/event_struct.h" 19 # include "event2/event_compat.h" 20 # endif 21 #else 22 # include "mini_event.h" 23 #endif 24 #include "rbtree.h" 25 #include "namedb.h" 26 #include "options.h" 27 #include "dns.h" 28 #include "tsig.h" 29 30 struct nsd; 31 struct region; 32 struct buffer; 33 struct xfrd_tcp; 34 struct xfrd_tcp_set; 35 struct notify_zone_t; 36 struct udb_ptr; 37 typedef struct xfrd_state xfrd_state_t; 38 typedef struct xfrd_zone xfrd_zone_t; 39 typedef struct xfrd_soa xfrd_soa_t; 40 /* 41 * The global state for the xfrd daemon process. 42 * The time_t times are epochs in secs since 1970, absolute times. 43 */ 44 struct xfrd_state { 45 /* time when daemon was last started */ 46 time_t xfrd_start_time; 47 struct region* region; 48 struct event_base* event_base; 49 struct nsd* nsd; 50 51 struct xfrd_tcp_set* tcp_set; 52 /* packet buffer for udp packets */ 53 struct buffer* packet; 54 /* udp waiting list, double linked list */ 55 struct xfrd_zone *udp_waiting_first, *udp_waiting_last; 56 /* number of udp sockets (for sending queries) in use */ 57 size_t udp_use_num; 58 /* activated waiting list, double linked list */ 59 struct xfrd_zone *activated_first; 60 61 /* current time is cached */ 62 uint8_t got_time; 63 time_t current_time; 64 65 /* counter for xfr file numbers */ 66 uint64_t xfrfilenumber; 67 68 /* the zonestat array size that we last saw and is safe to use */ 69 unsigned zonestat_safe; 70 /* size currently of the clear array */ 71 size_t zonestat_clear_num; 72 /* array of malloced entries with cumulative cleared stat values */ 73 struct nsdst** zonestat_clear; 74 75 /* timer for NSD reload */ 76 struct timeval reload_timeout; 77 struct event reload_handler; 78 int reload_added; 79 /* last reload must have caught all zone updates before this time */ 80 time_t reload_cmd_last_sent; 81 uint8_t can_send_reload; 82 pid_t reload_pid; 83 /* timeout for lost sigchild and reaping children */ 84 struct event child_timer; 85 int child_timer_added; 86 87 /* timeout event for zonefiles_write events */ 88 struct event write_timer; 89 /* set to 1 if zones have received xfrs since the last write_timer */ 90 int write_zonefile_needed; 91 92 /* communication channel with server_main */ 93 struct event ipc_handler; 94 int ipc_handler_flags; 95 struct xfrd_tcp *ipc_conn; 96 struct buffer* ipc_pass; 97 /* sending ipc to server_main */ 98 uint8_t need_to_send_shutdown; 99 uint8_t need_to_send_reload; 100 uint8_t need_to_send_stats; 101 uint8_t need_to_send_quit; 102 uint8_t ipc_send_blocked; 103 struct udb_ptr* last_task; 104 105 /* xfrd shutdown flag */ 106 uint8_t shutdown; 107 108 /* tree of zones, by apex name, contains xfrd_zone_t*. Only secondary zones. */ 109 rbtree_t *zones; 110 111 /* tree of zones, by apex name, contains notify_zone_t*. All zones. */ 112 rbtree_t *notify_zones; 113 /* number of notify_zone_t active using UDP socket */ 114 int notify_udp_num; 115 /* first and last notify_zone_t* entries waiting for a UDP socket */ 116 struct notify_zone_t *notify_waiting_first, *notify_waiting_last; 117 }; 118 119 /* 120 * XFR daemon SOA information kept in network format. 121 * This is in packet order. 122 */ 123 struct xfrd_soa { 124 /* name of RR is zone apex dname */ 125 uint16_t type; /* = TYPE_SOA */ 126 uint16_t klass; /* = CLASS_IN */ 127 uint32_t ttl; 128 uint16_t rdata_count; /* = 7 */ 129 /* format is 1 octet length, + wireformat dname. 130 one more octet since parse_dname_wire_from_packet needs it. 131 maximum size is allocated to avoid memory alloc/free. */ 132 uint8_t prim_ns[MAXDOMAINLEN + 2]; 133 uint8_t email[MAXDOMAINLEN + 2]; 134 uint32_t serial; 135 uint32_t refresh; 136 uint32_t retry; 137 uint32_t expire; 138 uint32_t minimum; 139 }; 140 141 142 /* 143 * XFRD state for a single zone 144 */ 145 struct xfrd_zone { 146 rbnode_t node; 147 148 /* name of the zone */ 149 const dname_type* apex; 150 const char* apex_str; 151 152 /* Three types of soas: 153 * NSD: in use by running server 154 * disk: stored on disk in db/diff file 155 * notified: from notification, could be available on a master. 156 * And the time the soa was acquired (start time for timeouts). 157 * If the time==0, no SOA is available. 158 */ 159 xfrd_soa_t soa_nsd; 160 time_t soa_nsd_acquired; 161 xfrd_soa_t soa_disk; 162 time_t soa_disk_acquired; 163 xfrd_soa_t soa_notified; 164 time_t soa_notified_acquired; 165 166 enum xfrd_zone_state { 167 xfrd_zone_ok, 168 xfrd_zone_refreshing, 169 xfrd_zone_expired 170 } state; 171 172 /* master to try to transfer from, number for persistence */ 173 acl_options_t* master; 174 int master_num; 175 int next_master; /* -1 or set by notify where to try next */ 176 /* round of xfrattempts, -1 is waiting for timeout */ 177 int round_num; 178 zone_options_t* zone_options; 179 int fresh_xfr_timeout; 180 181 /* handler for timeouts */ 182 struct timeval timeout; 183 struct event zone_handler; 184 int zone_handler_flags; 185 int event_added; 186 187 /* tcp connection zone is using, or -1 */ 188 int tcp_conn; 189 /* zone is waiting for a tcp connection */ 190 uint8_t tcp_waiting; 191 /* next zone in waiting list */ 192 xfrd_zone_t* tcp_waiting_next; 193 xfrd_zone_t* tcp_waiting_prev; 194 /* zone is in its tcp send queue */ 195 uint8_t in_tcp_send; 196 /* next zone in tcp send queue */ 197 xfrd_zone_t* tcp_send_next; 198 xfrd_zone_t* tcp_send_prev; 199 /* zone is waiting for a udp connection (tcp is preferred) */ 200 uint8_t udp_waiting; 201 /* next zone in waiting list for UDP */ 202 xfrd_zone_t* udp_waiting_next; 203 xfrd_zone_t* udp_waiting_prev; 204 /* zone has been activated to run now (after the other events 205 * but before blocking in select again) */ 206 uint8_t is_activated; 207 xfrd_zone_t* activated_next; 208 xfrd_zone_t* activated_prev; 209 210 /* xfr message handling data */ 211 /* query id */ 212 uint16_t query_id; 213 uint32_t msg_seq_nr; /* number of messages already handled */ 214 uint32_t msg_old_serial, msg_new_serial; /* host byte order */ 215 size_t msg_rr_count; 216 uint8_t msg_is_ixfr; /* 1:IXFR detected. 2:middle IXFR SOA seen. */ 217 tsig_record_type tsig; /* tsig state for IXFR/AXFR */ 218 uint64_t xfrfilenumber; /* identifier for file to store xfr into, 219 valid if msg_seq_nr nonzero */ 220 }; 221 222 enum xfrd_packet_result { 223 xfrd_packet_bad, /* drop the packet/connection */ 224 xfrd_packet_drop, /* drop the connection, but not report bad */ 225 xfrd_packet_more, /* more packets to follow on tcp */ 226 xfrd_packet_notimpl, /* server responded with NOTIMPL or FORMATERR */ 227 xfrd_packet_tcp, /* try tcp connection */ 228 xfrd_packet_transfer, /* server responded with transfer*/ 229 xfrd_packet_newlease /* no changes, soa OK */ 230 }; 231 232 /* 233 Division of the (portably: 1024) max number of sockets that can be open. 234 The sum of the below numbers should be below the user limit for sockets 235 open, or you see errors in your logfile. 236 And it should be below FD_SETSIZE, to be able to select() on replies. 237 Note that also some sockets are used for writing the ixfr.db, xfrd.state 238 files and for the pipes to the main parent process. 239 */ 240 #define XFRD_MAX_TCP 32 /* max number of TCP AXFR/IXFR concurrent connections.*/ 241 /* Each entry has 64Kb buffer preallocated.*/ 242 #define XFRD_MAX_UDP 64 /* max number of UDP sockets at a time for IXFR */ 243 #define XFRD_MAX_UDP_NOTIFY 64 /* max concurrent UDP sockets for NOTIFY */ 244 245 extern xfrd_state_t* xfrd; 246 247 /* start xfrd, new start. Pass socket to server_main. */ 248 void xfrd_init(int socket, struct nsd* nsd, int shortsoa, int reload_active, 249 pid_t nsd_pid); 250 251 /* add new slave zone, dname(from zone_opt) and given options */ 252 void xfrd_init_slave_zone(xfrd_state_t* xfrd, zone_options_t* zone_opt); 253 254 /* delete slave zone */ 255 void xfrd_del_slave_zone(xfrd_state_t* xfrd, const dname_type* dname); 256 257 /* get the current time epoch. Cached for speed. */ 258 time_t xfrd_time(void); 259 260 /* 261 * Handle final received packet from network. 262 * returns enum of packet discovery results 263 */ 264 enum xfrd_packet_result xfrd_handle_received_xfr_packet( 265 xfrd_zone_t* zone, buffer_type* packet); 266 267 /* set timer to specific value */ 268 void xfrd_set_timer(xfrd_zone_t* zone, time_t t); 269 /* set refresh timer of zone to refresh at time now */ 270 void xfrd_set_refresh_now(xfrd_zone_t* zone); 271 /* unset the timer - no more timeouts, for when zone is queued */ 272 void xfrd_unset_timer(xfrd_zone_t* zone); 273 /* remove the 'refresh now', remove it from the activated list */ 274 void xfrd_deactivate_zone(xfrd_zone_t* z); 275 276 /* 277 * Make a new request to next master server. 278 * uses next_master if set (and a fresh set of rounds). 279 * otherwised, starts new round of requests if none started already. 280 * starts next round of requests if at last master. 281 * if too many rounds of requests, sets timer for next retry. 282 */ 283 void xfrd_make_request(xfrd_zone_t* zone); 284 285 /* 286 * send packet via udp (returns UDP fd source socket) to acl addr. 287 * returns -1 on failure. 288 */ 289 int xfrd_send_udp(acl_options_t* acl, buffer_type* packet, acl_options_t* ifc); 290 291 /* 292 * read from udp port packet into buffer, returns 0 on failure 293 */ 294 int xfrd_udp_read_packet(buffer_type* packet, int fd); 295 296 /* 297 * Release udp socket that a zone is using 298 */ 299 void xfrd_udp_release(xfrd_zone_t* zone); 300 301 /* 302 * Get a static buffer for temporary use (to build a packet). 303 */ 304 struct buffer* xfrd_get_temp_buffer(void); 305 306 /* 307 * TSIG sign outgoing request. Call if acl has a key. 308 */ 309 void xfrd_tsig_sign_request(buffer_type* packet, struct tsig_record* tsig, 310 acl_options_t* acl); 311 312 /* handle incoming soa information (NSD is running it, time acquired=guess). 313 Pass soa=NULL,acquired=now if NSD has nothing loaded for the zone 314 (i.e. zonefile was deleted). */ 315 void xfrd_handle_incoming_soa(xfrd_zone_t* zone, xfrd_soa_t* soa, 316 time_t acquired); 317 /* handle a packet passed along ipc route. acl is the one that accepted 318 the packet. The packet is the network blob received. acl_xfr is 319 provide-xfr acl matching notify sender or -1 */ 320 void xfrd_handle_passed_packet(buffer_type* packet, 321 int acl_num, int acl_xfr); 322 323 /* try to reopen the logfile. */ 324 void xfrd_reopen_logfile(void); 325 326 /* free namedb for xfrd usage */ 327 void xfrd_free_namedb(struct nsd* nsd); 328 329 /* copy SOA info from rr to soa struct. */ 330 void xfrd_copy_soa(xfrd_soa_t* soa, rr_type* rr); 331 332 /* check for failed updates - it is assumed that now the reload has 333 finished, and all zone SOAs have been sent. */ 334 void xfrd_check_failed_updates(void); 335 336 /* 337 * Prepare zones for a reload, this sets the times on the zones to be 338 * before the current time, so the reload happens after. 339 */ 340 void xfrd_prepare_zones_for_reload(void); 341 342 /* Bind a local interface to a socket descriptor, return 1 on success */ 343 int xfrd_bind_local_interface(int sockd, acl_options_t* ifc, 344 acl_options_t* acl, int tcp); 345 346 /* process results and soa info from reload */ 347 void xfrd_process_task_result(xfrd_state_t* xfrd, struct udb_base* taskudb); 348 349 /* set to reload right away (for user controlled reload events) */ 350 void xfrd_set_reload_now(xfrd_state_t* xfrd); 351 352 /* send expiry notifications to nsd */ 353 void xfrd_send_expire_notification(xfrd_zone_t* zone); 354 355 /* handle incoming notify (soa or NULL) and start zone xfr if necessary */ 356 void xfrd_handle_notify_and_start_xfr(xfrd_zone_t* zone, xfrd_soa_t* soa); 357 358 /* handle zone timeout, event */ 359 void xfrd_handle_zone(int fd, short event, void* arg); 360 361 const char* xfrd_pretty_time(time_t v); 362 363 #endif /* XFRD_H */ 364