1 /* 2 * services/outside_network.h - listen to answers from the network 3 * 4 * Copyright (c) 2007, NLnet Labs. All rights reserved. 5 * 6 * This software is open source. 7 * 8 * Redistribution and use in source and binary forms, with or without 9 * modification, are permitted provided that the following conditions 10 * are met: 11 * 12 * Redistributions of source code must retain the above copyright notice, 13 * this list of conditions and the following disclaimer. 14 * 15 * Redistributions in binary form must reproduce the above copyright notice, 16 * this list of conditions and the following disclaimer in the documentation 17 * and/or other materials provided with the distribution. 18 * 19 * Neither the name of the NLNET LABS nor the names of its contributors may 20 * be used to endorse or promote products derived from this software without 21 * specific prior written permission. 22 * 23 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 24 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 25 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 26 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 27 * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED 29 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 30 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF 31 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING 32 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 33 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 36 /** 37 * \file 38 * 39 * This file has functions to send queries to authoritative servers, 40 * and wait for the pending answer, with timeouts. 41 */ 42 43 #ifndef OUTSIDE_NETWORK_H 44 #define OUTSIDE_NETWORK_H 45 46 #include "util/alloc.h" 47 #include "util/rbtree.h" 48 #include "util/regional.h" 49 #include "util/netevent.h" 50 #include "dnstap/dnstap_config.h" 51 struct pending; 52 struct pending_timeout; 53 struct ub_randstate; 54 struct pending_tcp; 55 struct waiting_tcp; 56 struct waiting_udp; 57 struct reuse_tcp; 58 struct infra_cache; 59 struct port_comm; 60 struct port_if; 61 struct sldns_buffer; 62 struct serviced_query; 63 struct dt_env; 64 struct edns_option; 65 struct module_env; 66 struct module_qstate; 67 struct query_info; 68 struct config_file; 69 70 /** 71 * Send queries to outside servers and wait for answers from servers. 72 * Contains answer-listen sockets. 73 */ 74 struct outside_network { 75 /** Base for select calls */ 76 struct comm_base* base; 77 /** pointer to time in seconds */ 78 time_t* now_secs; 79 /** pointer to time in microseconds */ 80 struct timeval* now_tv; 81 82 /** buffer shared by UDP connections, since there is only one 83 datagram at any time. */ 84 struct sldns_buffer* udp_buff; 85 /** serviced_callbacks malloc overhead when processing multiple 86 * identical serviced queries to the same server. */ 87 size_t svcd_overhead; 88 /** use x20 bits to encode additional ID random bits */ 89 int use_caps_for_id; 90 /** outside network wants to quit. Stop queued msgs from sent. */ 91 int want_to_quit; 92 93 /** number of unwanted replies received (for statistics) */ 94 size_t unwanted_replies; 95 /** cumulative total of unwanted replies (for defense) */ 96 size_t unwanted_total; 97 /** threshold when to take defensive action. If 0 then never. */ 98 size_t unwanted_threshold; 99 /** what action to take, called when defensive action is needed */ 100 void (*unwanted_action)(void*); 101 /** user param for action */ 102 void* unwanted_param; 103 104 /** linked list of available commpoints, unused file descriptors, 105 * for use as outgoing UDP ports. cp.fd=-1 in them. */ 106 struct port_comm* unused_fds; 107 /** if udp is done */ 108 int do_udp; 109 /** if udp is delay-closed (delayed answers do not meet closed port)*/ 110 int delayclose; 111 /** timeout for delayclose */ 112 struct timeval delay_tv; 113 /** if we perform udp-connect, connect() for UDP socket to mitigate 114 * ICMP side channel leakage */ 115 int udp_connect; 116 /** number of udp packets sent. */ 117 size_t num_udp_outgoing; 118 119 /** array of outgoing IP4 interfaces */ 120 struct port_if* ip4_ifs; 121 /** number of outgoing IP4 interfaces */ 122 int num_ip4; 123 124 /** array of outgoing IP6 interfaces */ 125 struct port_if* ip6_ifs; 126 /** number of outgoing IP6 interfaces */ 127 int num_ip6; 128 129 /** pending udp queries waiting to be sent out, waiting for fd */ 130 struct pending* udp_wait_first; 131 /** last pending udp query in list */ 132 struct pending* udp_wait_last; 133 134 /** pending udp answers. sorted by id, addr */ 135 rbtree_type* pending; 136 /** serviced queries, sorted by qbuf, addr, dnssec */ 137 rbtree_type* serviced; 138 /** host cache, pointer but not owned by outnet. */ 139 struct infra_cache* infra; 140 /** where to get random numbers */ 141 struct ub_randstate* rnd; 142 /** ssl context to create ssl wrapped TCP with DNS connections */ 143 void* sslctx; 144 /** if SNI will be used for TLS connections */ 145 int tls_use_sni; 146 #ifdef USE_DNSTAP 147 /** dnstap environment */ 148 struct dt_env* dtenv; 149 #endif 150 /** maximum segment size of tcp socket */ 151 int tcp_mss; 152 /** IP_TOS socket option requested on the sockets */ 153 int ip_dscp; 154 155 /** 156 * Array of tcp pending used for outgoing TCP connections. 157 * Each can be used to establish a TCP connection with a server. 158 * The file descriptors are -1 if they are free, and need to be 159 * opened for the tcp connection. Can be used for ip4 and ip6. 160 */ 161 struct pending_tcp **tcp_conns; 162 /** number of tcp communication points. */ 163 size_t num_tcp; 164 /** number of tcp communication points in use. */ 165 size_t num_tcp_outgoing; 166 /** max number of queries on a reuse connection */ 167 size_t max_reuse_tcp_queries; 168 /** timeout for REUSE entries in milliseconds. */ 169 int tcp_reuse_timeout; 170 /** timeout in milliseconds for TCP queries to auth servers. */ 171 int tcp_auth_query_timeout; 172 /** 173 * tree of still-open and waiting tcp connections for reuse. 174 * can be closed and reopened to get a new tcp connection. 175 * or reused to the same destination again. with timeout to close. 176 * Entries are of type struct reuse_tcp. 177 * The entries are both active and empty connections. 178 */ 179 rbtree_type tcp_reuse; 180 /** max number of tcp_reuse entries we want to keep open */ 181 size_t tcp_reuse_max; 182 /** first and last(oldest) in lru list of reuse connections. 183 * the oldest can be closed to get a new free pending_tcp if needed 184 * The list contains empty connections, that wait for timeout or 185 * a new query that can use the existing connection. */ 186 struct reuse_tcp* tcp_reuse_first, *tcp_reuse_last; 187 /** list of tcp comm points that are free for use */ 188 struct pending_tcp* tcp_free; 189 /** list of tcp queries waiting for a buffer */ 190 struct waiting_tcp* tcp_wait_first; 191 /** last of waiting query list */ 192 struct waiting_tcp* tcp_wait_last; 193 }; 194 195 /** 196 * Outgoing interface. Ports available and currently used are tracked 197 * per interface 198 */ 199 struct port_if { 200 /** address ready to allocate new socket (except port no). */ 201 struct sockaddr_storage addr; 202 /** length of addr field */ 203 socklen_t addrlen; 204 205 /** prefix length of network address (in bits), for randomisation. 206 * if 0, no randomisation. */ 207 int pfxlen; 208 209 #ifndef DISABLE_EXPLICIT_PORT_RANDOMISATION 210 /** the available ports array. These are unused. 211 * Only the first total-inuse part is filled. */ 212 int* avail_ports; 213 /** the total number of available ports (size of the array) */ 214 int avail_total; 215 #endif 216 217 /** array of the commpoints currently in use. 218 * allocated for max number of fds, first part in use. */ 219 struct port_comm** out; 220 /** max number of fds, size of out array */ 221 int maxout; 222 /** number of commpoints (and thus also ports) in use */ 223 int inuse; 224 }; 225 226 /** 227 * Outgoing commpoint for UDP port. 228 */ 229 struct port_comm { 230 /** next in free list */ 231 struct port_comm* next; 232 /** which port number (when in use) */ 233 int number; 234 /** interface it is used in */ 235 struct port_if* pif; 236 /** index in the out array of the interface */ 237 int index; 238 /** number of outstanding queries on this port */ 239 int num_outstanding; 240 /** UDP commpoint, fd=-1 if not in use */ 241 struct comm_point* cp; 242 }; 243 244 /** 245 * Reuse TCP connection, still open can be used again. 246 */ 247 struct reuse_tcp { 248 /** rbtree node with links in tcp_reuse tree. key is NULL when not 249 * in tree. Both active and empty connections are in the tree. 250 * key is a pointer to this structure, the members used to compare 251 * are the sockaddr and and then is-ssl bool, and then ptr value is 252 * used in case the same address exists several times in the tree 253 * when there are multiple connections to the same destination to 254 * make the rbtree items unique. */ 255 rbnode_type node; 256 /** the key for the tcp_reuse tree. address of peer, ip4 or ip6, 257 * and port number of peer */ 258 struct sockaddr_storage addr; 259 /** length of addr */ 260 socklen_t addrlen; 261 /** also key for tcp_reuse tree, if ssl is used */ 262 int is_ssl; 263 /** lru chain, so that the oldest can be removed to get a new 264 * connection when all are in (re)use. oldest is last in list. 265 * The lru only contains empty connections waiting for reuse, 266 * the ones with active queries are not on the list because they 267 * do not need to be closed to make space for others. They already 268 * service a query so the close for another query does not help 269 * service a larger number of queries. */ 270 struct reuse_tcp* lru_next, *lru_prev; 271 /** true if the reuse_tcp item is on the lru list with empty items */ 272 int item_on_lru_list; 273 /** the connection to reuse, the fd is non-1 and is open. 274 * the addr and port determine where the connection is going, 275 * and is key to the rbtree. The SSL ptr determines if it is 276 * a TLS connection or a plain TCP connection there. And TLS 277 * or not is also part of the key to the rbtree. 278 * There is a timeout and read event on the fd, to close it. */ 279 struct pending_tcp* pending; 280 /** 281 * The more read again value pointed to by the commpoint 282 * tcp_more_read_again pointer, so that it exists after commpoint 283 * delete 284 */ 285 int cp_more_read_again; 286 /** 287 * The more write again value pointed to by the commpoint 288 * tcp_more_write_again pointer, so that it exists after commpoint 289 * delete 290 */ 291 int cp_more_write_again; 292 /** rbtree with other queries waiting on the connection, by ID number, 293 * of type struct waiting_tcp. It is for looking up received 294 * answers to the structure for callback. And also to see if ID 295 * numbers are unused and can be used for a new query. 296 * The write_wait elements are also in the tree, so that ID numbers 297 * can be looked up also for them. They are bool write_wait_queued. */ 298 rbtree_type tree_by_id; 299 /** list of queries waiting to be written on the channel, 300 * if NULL no queries are waiting to be written and the pending->query 301 * is the query currently serviced. The first is the next in line. 302 * They are also in the tree_by_id. Once written, the are removed 303 * from this list, but stay in the tree. */ 304 struct waiting_tcp* write_wait_first, *write_wait_last; 305 /** the outside network it is part of */ 306 struct outside_network* outnet; 307 }; 308 309 /** 310 * A query that has an answer pending for it. 311 */ 312 struct pending { 313 /** redblacktree entry, key is the pending struct(id, addr). */ 314 rbnode_type node; 315 /** the ID for the query. int so that a value out of range can 316 * be used to signify a pending that is for certain not present in 317 * the rbtree. (and for which deletion is safe). */ 318 unsigned int id; 319 /** remote address. */ 320 struct sockaddr_storage addr; 321 /** length of addr field in use. */ 322 socklen_t addrlen; 323 /** comm point it was sent on (and reply must come back on). */ 324 struct port_comm* pc; 325 /** timeout event */ 326 struct comm_timer* timer; 327 /** callback for the timeout, error or reply to the message */ 328 comm_point_callback_type* cb; 329 /** callback user argument */ 330 void* cb_arg; 331 /** the outside network it is part of */ 332 struct outside_network* outnet; 333 /** the corresponding serviced_query */ 334 struct serviced_query* sq; 335 336 /*---- filled if udp pending is waiting -----*/ 337 /** next in waiting list. */ 338 struct pending* next_waiting; 339 /** timeout in msec */ 340 int timeout; 341 /** The query itself, the query packet to send. */ 342 uint8_t* pkt; 343 /** length of query packet. */ 344 size_t pkt_len; 345 }; 346 347 /** 348 * Pending TCP query to server. 349 */ 350 struct pending_tcp { 351 /** next in list of free tcp comm points, or NULL. */ 352 struct pending_tcp* next_free; 353 /** port for of the outgoing interface that is used */ 354 struct port_if* pi; 355 /** tcp comm point it was sent on (and reply must come back on). */ 356 struct comm_point* c; 357 /** the query being serviced, NULL if the pending_tcp is unused. */ 358 struct waiting_tcp* query; 359 /** the pre-allocated reuse tcp structure. if ->pending is nonNULL 360 * it is in use and the connection is waiting for reuse. 361 * It is here for memory pre-allocation, and used to make this 362 * pending_tcp wait for reuse. */ 363 struct reuse_tcp reuse; 364 }; 365 366 /** 367 * Query waiting for TCP buffer. 368 */ 369 struct waiting_tcp { 370 /** 371 * next in waiting list. 372 * if on_tcp_waiting_list==0, this points to the pending_tcp structure. 373 */ 374 struct waiting_tcp* next_waiting; 375 /** if true the item is on the tcp waiting list and next_waiting 376 * is used for that. If false, the next_waiting points to the 377 * pending_tcp */ 378 int on_tcp_waiting_list; 379 /** next and prev in query waiting list for stream connection */ 380 struct waiting_tcp* write_wait_prev, *write_wait_next; 381 /** true if the waiting_tcp structure is on the write_wait queue */ 382 int write_wait_queued; 383 /** entry in reuse.tree_by_id, if key is NULL, not in tree, otherwise, 384 * this struct is key and sorted by ID (from waiting_tcp.id). */ 385 rbnode_type id_node; 386 /** the ID for the query; checked in reply */ 387 uint16_t id; 388 /** timeout event; timer keeps running whether the query is 389 * waiting for a buffer or the tcp reply is pending */ 390 struct comm_timer* timer; 391 /** timeout in msec */ 392 int timeout; 393 /** the outside network it is part of */ 394 struct outside_network* outnet; 395 /** remote address. */ 396 struct sockaddr_storage addr; 397 /** length of addr field in use. */ 398 socklen_t addrlen; 399 /** 400 * The query itself, the query packet to send. 401 * allocated after the waiting_tcp structure. 402 */ 403 uint8_t* pkt; 404 /** length of query packet. */ 405 size_t pkt_len; 406 /** callback for the timeout, error or reply to the message, 407 * or NULL if no user is waiting. the entry uses an ID number. 408 * a query that was written is no longer needed, but the ID number 409 * and a reply will come back and can be ignored if NULL */ 410 comm_point_callback_type* cb; 411 /** callback user argument */ 412 void* cb_arg; 413 /** if it uses ssl upstream */ 414 int ssl_upstream; 415 /** ref to the tls_auth_name from the serviced_query */ 416 char* tls_auth_name; 417 /** the packet was involved in an error, to stop looping errors */ 418 int error_count; 419 /** if true, the item is at the cb_and_decommission stage */ 420 int in_cb_and_decommission; 421 #ifdef USE_DNSTAP 422 /** serviced query pointer for dnstap to get logging info, if nonNULL*/ 423 struct serviced_query* sq; 424 #endif 425 }; 426 427 /** 428 * Callback to party interested in serviced query results. 429 */ 430 struct service_callback { 431 /** next in callback list */ 432 struct service_callback* next; 433 /** callback function */ 434 comm_point_callback_type* cb; 435 /** user argument for callback function */ 436 void* cb_arg; 437 }; 438 439 /** fallback size for fragmentation for EDNS in IPv4 */ 440 #define EDNS_FRAG_SIZE_IP4 1472 441 /** fallback size for EDNS in IPv6, fits one fragment with ip6-tunnel-ids */ 442 #define EDNS_FRAG_SIZE_IP6 1232 443 444 /** 445 * Query service record. 446 * Contains query and destination. UDP, TCP, EDNS are all tried. 447 * complete with retries and timeouts. A number of interested parties can 448 * receive a callback. 449 */ 450 struct serviced_query { 451 /** The rbtree node, key is this record */ 452 rbnode_type node; 453 /** The query that needs to be answered. Starts with flags u16, 454 * then qdcount, ..., including qname, qtype, qclass. Does not include 455 * EDNS record. */ 456 uint8_t* qbuf; 457 /** length of qbuf. */ 458 size_t qbuflen; 459 /** If an EDNS section is included, the DO/CD bit will be turned on. */ 460 int dnssec; 461 /** We want signatures, or else the answer is likely useless */ 462 int want_dnssec; 463 /** ignore capsforid */ 464 int nocaps; 465 /** tcp upstream used, use tcp, or ssl_upstream for SSL */ 466 int tcp_upstream, ssl_upstream; 467 /** the name of the tls authentication name, eg. 'ns.example.com' 468 * or NULL */ 469 char* tls_auth_name; 470 /** where to send it */ 471 struct sockaddr_storage addr; 472 /** length of addr field in use. */ 473 socklen_t addrlen; 474 /** zone name, uncompressed domain name in wireformat */ 475 uint8_t* zone; 476 /** length of zone name */ 477 size_t zonelen; 478 /** qtype */ 479 int qtype; 480 /** current status */ 481 enum serviced_query_status { 482 /** initial status */ 483 serviced_initial, 484 /** UDP with EDNS sent */ 485 serviced_query_UDP_EDNS, 486 /** UDP without EDNS sent */ 487 serviced_query_UDP, 488 /** TCP with EDNS sent */ 489 serviced_query_TCP_EDNS, 490 /** TCP without EDNS sent */ 491 serviced_query_TCP, 492 /** probe to test noEDNS0 (EDNS gives FORMERRorNOTIMP) */ 493 serviced_query_UDP_EDNS_fallback, 494 /** probe to test TCP noEDNS0 (EDNS gives FORMERRorNOTIMP) */ 495 serviced_query_TCP_EDNS_fallback, 496 /** send UDP query with EDNS1480 (or 1280) */ 497 serviced_query_UDP_EDNS_FRAG 498 } 499 /** variable with current status */ 500 status; 501 /** true if serviced_query is scheduled for deletion already */ 502 int to_be_deleted; 503 /** number of UDP retries */ 504 int retry; 505 /** time last UDP was sent */ 506 struct timeval last_sent_time; 507 /** rtt of last message */ 508 int last_rtt; 509 /** do we know edns probe status already, for UDP_EDNS queries */ 510 int edns_lame_known; 511 /** edns options to use for sending upstream packet */ 512 struct edns_option* opt_list; 513 /** outside network this is part of */ 514 struct outside_network* outnet; 515 /** list of interested parties that need callback on results. */ 516 struct service_callback* cblist; 517 /** the UDP or TCP query that is pending, see status which */ 518 void* pending; 519 /** block size with which to pad encrypted queries (default: 128) */ 520 size_t padding_block_size; 521 /** region for this serviced query. Will be cleared when this 522 * serviced_query will be deleted */ 523 struct regional* region; 524 /** allocation service for the region */ 525 struct alloc_cache* alloc; 526 /** flash timer to start the net I/O as a separate event */ 527 struct comm_timer* timer; 528 /** true if serviced_query is currently doing net I/O and may block */ 529 int busy; 530 }; 531 532 /** 533 * Create outside_network structure with N udp ports. 534 * @param base: the communication base to use for event handling. 535 * @param bufsize: size for network buffers. 536 * @param num_ports: number of udp ports to open per interface. 537 * @param ifs: interface names (or NULL for default interface). 538 * These interfaces must be able to access all authoritative servers. 539 * @param num_ifs: number of names in array ifs. 540 * @param do_ip4: service IP4. 541 * @param do_ip6: service IP6. 542 * @param num_tcp: number of outgoing tcp buffers to preallocate. 543 * @param dscp: DSCP to use. 544 * @param infra: pointer to infra cached used for serviced queries. 545 * @param rnd: stored to create random numbers for serviced queries. 546 * @param use_caps_for_id: enable to use 0x20 bits to encode id randomness. 547 * @param availports: array of available ports. 548 * @param numavailports: number of available ports in array. 549 * @param unwanted_threshold: when to take defensive action. 550 * @param unwanted_action: the action to take. 551 * @param unwanted_param: user parameter to action. 552 * @param tcp_mss: maximum segment size of tcp socket. 553 * @param do_udp: if udp is done. 554 * @param sslctx: context to create outgoing connections with (if enabled). 555 * @param delayclose: if not 0, udp sockets are delayed before timeout closure. 556 * msec to wait on timeouted udp sockets. 557 * @param tls_use_sni: if SNI is used for TLS connections. 558 * @param dtenv: environment to send dnstap events with (if enabled). 559 * @param udp_connect: if the udp_connect option is enabled. 560 * @param max_reuse_tcp_queries: max number of queries on a reuse connection. 561 * @param tcp_reuse_timeout: timeout for REUSE entries in milliseconds. 562 * @param tcp_auth_query_timeout: timeout in milliseconds for TCP queries to auth servers. 563 * @return: the new structure (with no pending answers) or NULL on error. 564 */ 565 struct outside_network* outside_network_create(struct comm_base* base, 566 size_t bufsize, size_t num_ports, char** ifs, int num_ifs, 567 int do_ip4, int do_ip6, size_t num_tcp, int dscp, struct infra_cache* infra, 568 struct ub_randstate* rnd, int use_caps_for_id, int* availports, 569 int numavailports, size_t unwanted_threshold, int tcp_mss, 570 void (*unwanted_action)(void*), void* unwanted_param, int do_udp, 571 void* sslctx, int delayclose, int tls_use_sni, struct dt_env *dtenv, 572 int udp_connect, int max_reuse_tcp_queries, int tcp_reuse_timeout, 573 int tcp_auth_query_timeout); 574 575 /** 576 * Delete outside_network structure. 577 * @param outnet: object to delete. 578 */ 579 void outside_network_delete(struct outside_network* outnet); 580 581 /** 582 * Prepare for quit. Sends no more queries, even if queued up. 583 * @param outnet: object to prepare for removal 584 */ 585 void outside_network_quit_prepare(struct outside_network* outnet); 586 587 /** 588 * Send UDP query, create pending answer. 589 * Changes the ID for the query to be random and unique for that destination. 590 * @param sq: serviced query. 591 * @param packet: wireformat query to send to destination. 592 * @param timeout: in milliseconds from now. 593 * @param callback: function to call on error, timeout or reply. 594 * @param callback_arg: user argument for callback function. 595 * @return: NULL on error for malloc or socket. Else the pending query object. 596 */ 597 struct pending* pending_udp_query(struct serviced_query* sq, 598 struct sldns_buffer* packet, int timeout, comm_point_callback_type* callback, 599 void* callback_arg); 600 601 /** 602 * Send TCP query. May wait for TCP buffer. Selects ID to be random, and 603 * checks id. 604 * @param sq: serviced query. 605 * @param packet: wireformat query to send to destination. copied from. 606 * @param timeout: in milliseconds from now. 607 * Timer starts running now. Timer may expire if all buffers are used, 608 * without any query been sent to the server yet. 609 * @param callback: function to call on error, timeout or reply. 610 * @param callback_arg: user argument for callback function. 611 * @return: false on error for malloc or socket. Else the pending TCP object. 612 */ 613 struct waiting_tcp* pending_tcp_query(struct serviced_query* sq, 614 struct sldns_buffer* packet, int timeout, comm_point_callback_type* callback, 615 void* callback_arg); 616 617 /** 618 * Delete pending answer. 619 * @param outnet: outside network the pending query is part of. 620 * Internal feature: if outnet is NULL, p is not unlinked from rbtree. 621 * @param p: deleted 622 */ 623 void pending_delete(struct outside_network* outnet, struct pending* p); 624 625 /** 626 * Perform a serviced query to the authoritative servers. 627 * Duplicate efforts are detected, and EDNS, TCP and UDP retry is performed. 628 * @param outnet: outside network, with rbtree of serviced queries. 629 * @param qinfo: query info. 630 * @param flags: flags u16 (host format), includes opcode, CD bit. 631 * @param dnssec: if set, DO bit is set in EDNS queries. 632 * If the value includes BIT_CD, CD bit is set when in EDNS queries. 633 * If the value includes BIT_DO, DO bit is set when in EDNS queries. 634 * @param want_dnssec: signatures are needed, without EDNS the answer is 635 * likely to be useless. 636 * @param nocaps: ignore use_caps_for_id and use unperturbed qname. 637 * @param check_ratelimit: if set, will check ratelimit before sending out. 638 * @param tcp_upstream: use TCP for upstream queries. 639 * @param ssl_upstream: use SSL for upstream queries. 640 * @param tls_auth_name: when ssl_upstream is true, use this name to check 641 * the server's peer certificate. 642 * @param addr: to which server to send the query. 643 * @param addrlen: length of addr. 644 * @param zone: name of the zone of the delegation point. wireformat dname. 645 This is the delegation point name for which the server is deemed 646 authoritative. 647 * @param zonelen: length of zone. 648 * @param qstate: module qstate. Mainly for inspecting the available 649 * edns_opts_lists. 650 * @param callback: callback function. 651 * @param callback_arg: user argument to callback function. 652 * @param buff: scratch buffer to create query contents in. Empty on exit. 653 * @param env: the module environment. 654 * @param was_ratelimited: it will signal back if the query failed to pass the 655 * ratelimit check. 656 * @return 0 on error, or pointer to serviced query that is used to answer 657 * this serviced query may be shared with other callbacks as well. 658 */ 659 struct serviced_query* outnet_serviced_query(struct outside_network* outnet, 660 struct query_info* qinfo, uint16_t flags, int dnssec, int want_dnssec, 661 int nocaps, int check_ratelimit, int tcp_upstream, int ssl_upstream, 662 char* tls_auth_name, struct sockaddr_storage* addr, socklen_t addrlen, 663 uint8_t* zone, size_t zonelen, struct module_qstate* qstate, 664 comm_point_callback_type* callback, void* callback_arg, 665 struct sldns_buffer* buff, struct module_env* env, int* was_ratelimited); 666 667 /** 668 * Remove service query callback. 669 * If that leads to zero callbacks, the query is completely cancelled. 670 * @param sq: serviced query to adjust. 671 * @param cb_arg: callback argument of callback that needs removal. 672 * same as the callback_arg to outnet_serviced_query(). 673 */ 674 void outnet_serviced_query_stop(struct serviced_query* sq, void* cb_arg); 675 676 /** 677 * Get memory size in use by outside network. 678 * Counts buffers and outstanding query (serviced queries) malloced data. 679 * @param outnet: outside network structure. 680 * @return size in bytes. 681 */ 682 size_t outnet_get_mem(struct outside_network* outnet); 683 684 /** 685 * Get memory size in use by serviced query while it is servicing callbacks. 686 * This takes into account the pre-deleted status of it; it will be deleted 687 * when the callbacks are done. 688 * @param sq: serviced query. 689 * @return size in bytes. 690 */ 691 size_t serviced_get_mem(struct serviced_query* sq); 692 693 /** Pick random ID value for a tcp stream, avoids existing IDs. */ 694 uint16_t reuse_tcp_select_id(struct reuse_tcp* reuse, 695 struct outside_network* outnet); 696 697 /** find element in tree by id */ 698 struct waiting_tcp* reuse_tcp_by_id_find(struct reuse_tcp* reuse, uint16_t id); 699 700 /** insert element in tree by id */ 701 void reuse_tree_by_id_insert(struct reuse_tcp* reuse, struct waiting_tcp* w); 702 703 /** insert element in tcp_reuse tree and LRU list */ 704 int reuse_tcp_insert(struct outside_network* outnet, 705 struct pending_tcp* pend_tcp); 706 707 /** touch the LRU of the element */ 708 void reuse_tcp_lru_touch(struct outside_network* outnet, 709 struct reuse_tcp* reuse); 710 711 /** remove element from tree and LRU list */ 712 void reuse_tcp_remove_tree_list(struct outside_network* outnet, 713 struct reuse_tcp* reuse); 714 715 /** snip the last reuse_tcp element off of the LRU list if any */ 716 struct reuse_tcp* reuse_tcp_lru_snip(struct outside_network* outnet); 717 718 /** delete readwait waiting_tcp elements, deletes the elements in the list */ 719 void reuse_del_readwait(rbtree_type* tree_by_id); 720 721 /** get TCP file descriptor for address, returns -1 on failure, 722 * tcp_mss is 0 or maxseg size to set for TCP packets. */ 723 int outnet_get_tcp_fd(struct sockaddr_storage* addr, socklen_t addrlen, 724 int tcp_mss, int dscp); 725 726 /** 727 * Create udp commpoint suitable for sending packets to the destination. 728 * @param outnet: outside_network with the comm_base it is attached to, 729 * with the outgoing interfaces chosen from, and rnd gen for random. 730 * @param cb: callback function for the commpoint. 731 * @param cb_arg: callback argument for cb. 732 * @param to_addr: intended destination. 733 * @param to_addrlen: length of to_addr. 734 * @return commpoint that you can comm_point_send_udp_msg with, or NULL. 735 */ 736 struct comm_point* outnet_comm_point_for_udp(struct outside_network* outnet, 737 comm_point_callback_type* cb, void* cb_arg, 738 struct sockaddr_storage* to_addr, socklen_t to_addrlen); 739 740 /** 741 * Create tcp commpoint suitable for communication to the destination. 742 * It also performs connect() to the to_addr. 743 * @param outnet: outside_network with the comm_base it is attached to, 744 * and the tcp_mss. 745 * @param cb: callback function for the commpoint. 746 * @param cb_arg: callback argument for cb. 747 * @param to_addr: intended destination. 748 * @param to_addrlen: length of to_addr. 749 * @param query: initial packet to send writing, in buffer. It is copied 750 * to the commpoint buffer that is created. 751 * @param timeout: timeout for the TCP connection. 752 * timeout in milliseconds, or -1 for no (change to the) timeout. 753 * So seconds*1000. 754 * @param ssl: set to true for TLS. 755 * @param host: hostname for host name verification of TLS (or NULL if no TLS). 756 * @return tcp_out commpoint, or NULL. 757 */ 758 struct comm_point* outnet_comm_point_for_tcp(struct outside_network* outnet, 759 comm_point_callback_type* cb, void* cb_arg, 760 struct sockaddr_storage* to_addr, socklen_t to_addrlen, 761 struct sldns_buffer* query, int timeout, int ssl, char* host); 762 763 /** 764 * Create http commpoint suitable for communication to the destination. 765 * Creates the http request buffer. It also performs connect() to the to_addr. 766 * @param outnet: outside_network with the comm_base it is attached to, 767 * and the tcp_mss. 768 * @param cb: callback function for the commpoint. 769 * @param cb_arg: callback argument for cb. 770 * @param to_addr: intended destination. 771 * @param to_addrlen: length of to_addr. 772 * @param timeout: timeout for the TCP connection. 773 * timeout in milliseconds, or -1 for no (change to the) timeout. 774 * So seconds*1000. 775 * @param ssl: set to true for https. 776 * @param host: hostname to use for the destination. part of http request. 777 * @param path: pathname to lookup, eg. name of the file on the destination. 778 * @param cfg: running configuration for User-Agent setup. 779 * @return http_out commpoint, or NULL. 780 */ 781 struct comm_point* outnet_comm_point_for_http(struct outside_network* outnet, 782 comm_point_callback_type* cb, void* cb_arg, 783 struct sockaddr_storage* to_addr, socklen_t to_addrlen, int timeout, 784 int ssl, char* host, char* path, struct config_file* cfg); 785 786 /** connect tcp connection to addr, 0 on failure */ 787 int outnet_tcp_connect(int s, struct sockaddr_storage* addr, socklen_t addrlen); 788 789 /** callback for incoming udp answers from the network */ 790 int outnet_udp_cb(struct comm_point* c, void* arg, int error, 791 struct comm_reply *reply_info); 792 793 /** callback for pending tcp connections */ 794 int outnet_tcp_cb(struct comm_point* c, void* arg, int error, 795 struct comm_reply *reply_info); 796 797 /** callback for udp timeout */ 798 void pending_udp_timer_cb(void *arg); 799 800 /** callback for udp delay for timeout */ 801 void pending_udp_timer_delay_cb(void *arg); 802 803 /** callback for outgoing TCP timer event */ 804 void outnet_tcptimer(void* arg); 805 806 /** callback to send serviced queries */ 807 void serviced_timer_cb(void *arg); 808 809 /** callback for serviced query UDP answers */ 810 int serviced_udp_callback(struct comm_point* c, void* arg, int error, 811 struct comm_reply* rep); 812 813 /** TCP reply or error callback for serviced queries */ 814 int serviced_tcp_callback(struct comm_point* c, void* arg, int error, 815 struct comm_reply* rep); 816 817 /** compare function of pending rbtree */ 818 int pending_cmp(const void* key1, const void* key2); 819 820 /** compare function of serviced query rbtree */ 821 int serviced_cmp(const void* key1, const void* key2); 822 823 /** compare function of reuse_tcp rbtree in outside_network struct */ 824 int reuse_cmp(const void* key1, const void* key2); 825 826 /** compare function of reuse_tcp tree_by_id rbtree */ 827 int reuse_id_cmp(const void* key1, const void* key2); 828 829 #endif /* OUTSIDE_NETWORK_H */ 830