2 * A rewrite of Darren Reed's original res.c As there is nothing
3 * left of Darren's original code, this is now licensed by the hybrid group.
4 * (Well, some of the function names are the same, and bits of the structs..)
5 * You can use it where it is useful, free even. Buy us a beer and stuff.
7 * The authors takes no responsibility for any damage or loss
8 * of property which results from the use of this software.
10 * July 1999 - Rewrote a bunch of stuff here. Change hostent builder code,
11 * added callbacks and reference counting of returned hostents.
12 * --Bleep (Thomas Helvey <tomh@inxpress.net>)
14 * This was all needlessly complicated for irc. Simplified. No more hostent
15 * All we really care about is the IP -> hostname mappings. Thats all.
17 * Apr 28, 2003 --cryogen and Dianora
20 * @brief IRC resolver functions.
25 #include "ircd_alloc.h"
27 #include "ircd_osdep.h"
28 #include "ircd_reply.h"
29 #include "ircd_string.h"
30 #include "ircd_snprintf.h"
33 #include "fileio.h" /* for fbopen / fbclose / fbputs */
41 #include "ircd_reslib.h"
43 /* #include <assert.h> -- Now using assert in ircd_log.h */
46 #include <sys/socket.h>
50 #error this code needs to be able to address individual octets
53 /** IPv4 resolver UDP socket. */
54 static struct Socket res_socket_v4;
55 /** IPv6 resolver UDP socket. */
56 static struct Socket res_socket_v6;
57 /** Next DNS lookup timeout. */
58 static struct Timer res_timeout;
59 /** Local address for IPv4 DNS lookups. */
60 struct irc_sockaddr VirtualHost_dns_v4;
61 /** Local address for IPv6 DNS lookups. */
62 struct irc_sockaddr VirtualHost_dns_v6;
63 /** Check for whether the resolver has been initialized yet. */
64 #define resolver_started() (request_list.next != NULL)
66 /** Maximum DNS packet length.
67 * RFC says 512, but we add extra for expanded names.
69 #define MAXPACKET 1024
70 #define AR_TTL 600 /**< TTL in seconds for dns cache entries */
72 /* RFC 1104/1105 wasn't very helpful about what these fields
73 * should be named, so for now, we'll just name them this way.
74 * we probably should look at what named calls them or something.
76 /** Size of TYPE field of a DNS RR header. */
77 #define TYPE_SIZE (size_t)2
78 /** Size of CLASS field of a DNS RR header. */
79 #define CLASS_SIZE (size_t)2
80 /** Size of TTL field of a DNS RR header. */
81 #define TTL_SIZE (size_t)4
82 /** Size of RDLENGTH field of a DNS RR header. */
83 #define RDLENGTH_SIZE (size_t)2
84 /** Size of fixed-format part of a DNS RR header. */
85 #define ANSWER_FIXED_SIZE (TYPE_SIZE + CLASS_SIZE + TTL_SIZE + RDLENGTH_SIZE)
87 /** Current request state. */
90 REQ_IDLE, /**< We're doing not much at all. */
91 REQ_PTR, /**< Looking up a PTR. */
92 REQ_A, /**< Looking up an A, possibly because AAAA failed. */
93 REQ_AAAA, /**< Looking up an AAAA. */
94 REQ_CNAME, /**< We got a CNAME in response, we better get a real answer next. */
95 REQ_INT /**< ip6.arpa failed, falling back to ip6.int. */
98 /** Doubly linked list node. */
101 struct dlink *prev; /**< Previous element in list. */
102 struct dlink *next; /**< Next element in list. */
105 /** A single resolver request.
106 * (Do not be fooled by the "list" in the name.)
110 struct dlink node; /**< Doubly linked list node. */
111 int id; /**< Request ID (from request header). */
112 int sent; /**< Number of requests sent. */
113 request_state state; /**< State the resolver machine is in. */
114 char type; /**< Current request type. */
115 char retries; /**< Retry counter. */
116 char sends; /**< Number of sends (>1 means resent). */
117 char resend; /**< Send flag; 0 == don't resend. */
118 time_t sentat; /**< Timestamp we last sent this request. */
119 time_t timeout; /**< When this request times out. */
120 struct irc_in_addr addr; /**< Address for this request. */
121 char *name; /**< Hostname for this request. */
122 dns_callback_f callback; /**< Callback function on completion. */
123 void *callback_ctx; /**< Context pointer for callback. */
126 /** Base of request list. */
127 static struct dlink request_list;
129 static void rem_request(struct reslist *request);
130 static struct reslist *make_request(dns_callback_f callback, void *ctx);
131 static void do_query_name(dns_callback_f callback, void *ctx,
132 const char* name, struct reslist *request, int);
133 static void do_query_number(dns_callback_f callback, void *ctx,
134 const struct irc_in_addr *,
135 struct reslist *request);
136 static void query_name(const char *name, int query_class, int query_type,
137 struct reslist *request);
138 static int send_res_msg(const char *buf, int len, int count);
139 static void resend_query(struct reslist *request);
140 static int proc_answer(struct reslist *request, HEADER *header, char *, char *);
141 static struct reslist *find_id(int id);
142 static void res_readreply(struct Event *ev);
143 static void timeout_resolver(struct Event *notused);
145 extern struct irc_sockaddr irc_nsaddr_list[IRCD_MAXNS];
146 extern int irc_nscount;
147 extern char irc_domain[HOSTLEN];
149 /** Prepare the resolver library to (optionally) accept a list of
150 * DNS servers through add_dns_server().
152 void clear_nameservers(void)
155 memset(&VirtualHost_dns_v4, 0, sizeof(VirtualHost_dns_v4));
156 memset(&VirtualHost_dns_v6, 0, sizeof(VirtualHost_dns_v6));
159 /** Check whether \a inp is a nameserver we use.
160 * @param[in] inp Nameserver address.
161 * @return Non-zero if we trust \a inp; zero if not.
164 res_ourserver(const struct irc_sockaddr *inp)
168 for (ns = 0; ns < irc_nscount; ns++)
169 if (!irc_in_addr_cmp(&inp->addr, &irc_nsaddr_list[ns].addr)
170 && inp->port == irc_nsaddr_list[ns].port)
176 /** Start (or re-start) resolver.
177 * This means read resolv.conf, initialize the list of pending
178 * requests, open the resolver socket and initialize its timeout.
181 restart_resolver(void)
189 if (!request_list.next)
190 request_list.next = request_list.prev = &request_list;
192 /* Check which address family (or families) our nameservers use. */
193 for (need_v4 = need_v6 = ns = 0; ns < irc_nscount; ns++)
195 if (irc_in_addr_is_ipv4(&irc_nsaddr_list[ns].addr))
201 /* If we need an IPv4 socket, and don't have one, open it. */
202 if (need_v4 && !s_active(&res_socket_v4))
204 int fd = os_socket(&VirtualHost_dns_v4, SOCK_DGRAM, "Resolver UDPv4 socket", AF_INET);
206 socket_add(&res_socket_v4, res_readreply, NULL,
207 SS_DATAGRAM, SOCK_EVENT_READABLE, fd);
211 /* If we need an IPv6 socket, and don't have one, open it. */
212 if (need_v6 && !s_active(&res_socket_v6))
214 int fd = os_socket(&VirtualHost_dns_v6, SOCK_DGRAM, "Resolver UDPv6 socket", AF_INET6);
216 socket_add(&res_socket_v6, res_readreply, NULL,
217 SS_DATAGRAM, SOCK_EVENT_READABLE, fd);
221 if (s_active(&res_socket_v4) || s_active(&res_socket_v6))
222 timer_init(&res_timeout);
225 /** Append local domain to hostname if needed.
226 * If \a hname does not contain any '.'s, append #irc_domain to it.
227 * @param[in,out] hname Hostname to check.
228 * @param[in] size Length of \a hname buffer.
231 add_local_domain(char* hname, size_t size)
233 /* try to fix up unqualified names
235 if (strchr(hname, '.') == NULL)
239 size_t len = strlen(hname);
241 if ((strlen(irc_domain) + len + 2) < size)
244 strcpy(hname + len, irc_domain);
250 /** Add a node to a doubly linked list.
251 * @param[in,out] node Node to add to list.
252 * @param[in,out] next Add \a node before this one.
255 add_dlink(struct dlink *node, struct dlink *next)
257 node->prev = next->prev;
259 node->prev->next = node;
260 node->next->prev = node;
263 /** Remove a request from the list and free it.
264 * @param[in] request Node to free.
267 rem_request(struct reslist *request)
269 /* remove from dlist */
270 request->node.prev->next = request->node.next;
271 request->node.next->prev = request->node.prev;
273 MyFree(request->name);
277 /** Create a DNS request record for the server.
278 * @param[in] query Callback information for caller.
279 * @return Newly allocated and linked-in reslist.
281 static struct reslist *
282 make_request(dns_callback_f callback, void *ctx)
284 struct reslist *request;
286 if (!resolver_started())
289 request = (struct reslist *)MyMalloc(sizeof(struct reslist));
290 memset(request, 0, sizeof(struct reslist));
292 request->state = REQ_IDLE;
293 request->sentat = CurrentTime;
294 request->retries = feature_int(FEAT_IRCD_RES_RETRIES);
296 request->timeout = feature_int(FEAT_IRCD_RES_TIMEOUT);
297 memset(&request->addr, 0, sizeof(request->addr));
298 request->callback = callback;
299 request->callback_ctx = ctx;
301 add_dlink(&request->node, &request_list);
305 /** Make sure that a timeout event will happen by the given time.
306 * @param[in] when Latest time for timeout to run.
309 check_resolver_timeout(time_t when)
311 if (when > CurrentTime + AR_TTL)
312 when = CurrentTime + AR_TTL;
313 /* TODO after 2.10.12: Rewrite the timer API because there should be
314 * no need for clients to know this kind of implementation detail. */
315 if (when > t_expire(&res_timeout))
317 else if (t_onqueue(&res_timeout) && !(res_timeout.t_header.gh_flags & GEN_MARKED))
318 timer_chg(&res_timeout, TT_ABSOLUTE, when);
320 timer_add(&res_timeout, timeout_resolver, NULL, TT_ABSOLUTE, when);
323 /** Drop pending DNS lookups which have timed out.
324 * @param[in] ev Timer event data (ignored).
327 timeout_resolver(struct Event *ev)
329 struct dlink *ptr, *next_ptr;
330 struct reslist *request;
331 time_t next_time = 0;
334 if (ev_type(ev) != ET_EXPIRE)
337 for (ptr = request_list.next; ptr != &request_list; ptr = next_ptr)
339 next_ptr = ptr->next;
340 request = (struct reslist*)ptr;
341 timeout = request->sentat + request->timeout;
343 if (CurrentTime >= timeout)
345 if (--request->retries <= 0)
347 Debug((DEBUG_DNS, "Request %p out of retries; destroying", request));
348 (*request->callback)(request->callback_ctx, NULL, NULL);
349 rem_request(request);
354 request->sentat = CurrentTime;
355 request->timeout += request->timeout;
356 resend_query(request);
360 if ((next_time == 0) || timeout < next_time)
366 if (next_time <= CurrentTime)
367 next_time = CurrentTime + AR_TTL;
368 check_resolver_timeout(next_time);
371 /** Drop queries that are associated with a particular pointer.
372 * This is used to clean up lookups for clients or conf blocks
374 * @param[in] vptr User callback pointer to search for.
377 delete_resolver_queries(const void *vptr)
379 struct dlink *ptr, *next_ptr;
380 struct reslist *request;
382 if (request_list.next) {
383 for (ptr = request_list.next; ptr != &request_list; ptr = next_ptr)
385 next_ptr = ptr->next;
386 request = (struct reslist*)ptr;
387 if (vptr == request->callback_ctx) {
388 Debug((DEBUG_DNS, "Removing request %p with vptr %p", request, vptr));
389 rem_request(request);
395 /** Send a message to all of our nameservers.
396 * @param[in] msg Message to send.
397 * @param[in] len Length of message.
398 * @param[in] rcount Maximum number of servers to ask.
399 * @return Number of servers that were successfully asked.
402 send_res_msg(const char *msg, int len, int rcount)
406 int max_queries = IRCD_MIN(irc_nscount, rcount);
408 /* RES_PRIMARY option is not implemented
409 * if (res.options & RES_PRIMARY || 0 == max_queries)
411 if (max_queries == 0)
414 for (i = 0; i < max_queries; i++) {
415 int fd = irc_in_addr_is_ipv4(&irc_nsaddr_list[i].addr) ? s_fd(&res_socket_v4) : s_fd(&res_socket_v6);
416 if (os_sendto_nonb(fd, msg, len, NULL, 0, &irc_nsaddr_list[i]) == IO_SUCCESS)
423 /** Find a DNS request by ID.
424 * @param[in] id Identifier to find.
425 * @return Matching DNS request, or NULL if none are found.
427 static struct reslist *
431 struct reslist *request;
433 for (ptr = request_list.next; ptr != &request_list; ptr = ptr->next)
435 request = (struct reslist*)ptr;
437 if (request->id == id) {
438 Debug((DEBUG_DNS, "find_id(%d) -> %p", id, request));
443 Debug((DEBUG_DNS, "find_id(%d) -> NULL", id));
447 /** Try to look up address for a hostname, trying IPv6 (T_AAAA) first.
448 * @param[in] name Hostname to look up.
449 * @param[in] query Callback information.
452 gethost_byname(const char *name, dns_callback_f callback, void *ctx)
454 do_query_name(callback, ctx, name, NULL, T_AAAA);
457 /** Try to look up hostname for an address.
458 * @param[in] addr Address to look up.
459 * @param[in] query Callback information.
462 gethost_byaddr(const struct irc_in_addr *addr, dns_callback_f callback, void *ctx)
464 do_query_number(callback, ctx, addr, NULL);
467 /** Send a query to look up the address for a name.
468 * @param[in] query Callback information.
469 * @param[in] name Hostname to look up.
470 * @param[in] request DNS lookup structure (may be NULL).
471 * @param[in] type Preferred request type.
474 do_query_name(dns_callback_f callback, void *ctx, const char *name,
475 struct reslist *request, int type)
477 char host_name[HOSTLEN + 1];
479 ircd_strncpy(host_name, name, HOSTLEN);
480 add_local_domain(host_name, HOSTLEN);
484 request = make_request(callback, ctx);
485 DupString(request->name, host_name);
488 request->state = REQ_AAAA;
491 request->state = REQ_A;
494 request->type = type;
495 Debug((DEBUG_DNS, "Requesting DNS %s %s as %p", (request->state == REQ_AAAA ? "AAAA" : "A"), host_name, request));
496 query_name(host_name, C_IN, type, request);
499 /** Send a query to look up the name for an address.
500 * @param[in] query Callback information.
501 * @param[in] addr Address to look up.
502 * @param[in] request DNS lookup structure (may be NULL).
505 do_query_number(dns_callback_f callback, void *ctx, const struct irc_in_addr *addr,
506 struct reslist *request)
509 const unsigned char *cp;
511 if (irc_in_addr_is_ipv4(addr))
513 cp = (const unsigned char*)&addr->in6_16[6];
514 ircd_snprintf(NULL, ipbuf, sizeof(ipbuf), "%u.%u.%u.%u.in-addr.arpa.",
515 (unsigned int)(cp[3]), (unsigned int)(cp[2]),
516 (unsigned int)(cp[1]), (unsigned int)(cp[0]));
522 if (request != NULL && request->state == REQ_INT)
527 cp = (const unsigned char *)&addr->in6_16[0];
528 ircd_snprintf(NULL, ipbuf, sizeof(ipbuf),
529 "%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x."
530 "%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.ip6.%s.",
531 (unsigned int)(cp[15]&0xf), (unsigned int)(cp[15]>>4),
532 (unsigned int)(cp[14]&0xf), (unsigned int)(cp[14]>>4),
533 (unsigned int)(cp[13]&0xf), (unsigned int)(cp[13]>>4),
534 (unsigned int)(cp[12]&0xf), (unsigned int)(cp[12]>>4),
535 (unsigned int)(cp[11]&0xf), (unsigned int)(cp[11]>>4),
536 (unsigned int)(cp[10]&0xf), (unsigned int)(cp[10]>>4),
537 (unsigned int)(cp[9]&0xf), (unsigned int)(cp[9]>>4),
538 (unsigned int)(cp[8]&0xf), (unsigned int)(cp[8]>>4),
539 (unsigned int)(cp[7]&0xf), (unsigned int)(cp[7]>>4),
540 (unsigned int)(cp[6]&0xf), (unsigned int)(cp[6]>>4),
541 (unsigned int)(cp[5]&0xf), (unsigned int)(cp[5]>>4),
542 (unsigned int)(cp[4]&0xf), (unsigned int)(cp[4]>>4),
543 (unsigned int)(cp[3]&0xf), (unsigned int)(cp[3]>>4),
544 (unsigned int)(cp[2]&0xf), (unsigned int)(cp[2]>>4),
545 (unsigned int)(cp[1]&0xf), (unsigned int)(cp[1]>>4),
546 (unsigned int)(cp[0]&0xf), (unsigned int)(cp[0]>>4), intarpa);
550 request = make_request(callback, ctx);
551 request->state= REQ_PTR;
552 request->type = T_PTR;
553 memcpy(&request->addr, addr, sizeof(request->addr));
554 request->name = (char *)MyMalloc(HOSTLEN + 1);
556 Debug((DEBUG_DNS, "Requesting DNS PTR %s as %p", ipbuf, request));
557 query_name(ipbuf, C_IN, T_PTR, request);
560 /** Generate a query based on class, type and name.
561 * @param[in] name Domain name to look up.
562 * @param[in] query_class Query class (see RFC 1035).
563 * @param[in] type Query type (see RFC 1035).
564 * @param[in] request DNS request structure.
567 query_name(const char *name, int query_class, int type,
568 struct reslist *request)
573 memset(buf, 0, sizeof(buf));
575 if ((request_len = irc_res_mkquery(name, query_class, type,
576 (unsigned char *)buf, sizeof(buf))) > 0)
578 HEADER *header = (HEADER *)buf;
581 * generate an unique id
582 * NOTE: we don't have to worry about converting this to and from
583 * network byte order, the nameserver does not interpret this value
584 * and returns it unchanged
588 header->id = (header->id + ircrandom()) & 0xffff;
589 } while (find_id(header->id));
590 request->id = header->id;
593 request->sent += send_res_msg(buf, request_len, request->sends);
594 check_resolver_timeout(request->sentat + request->timeout);
598 /** Send a failed DNS lookup request again.
599 * @param[in] request Request to resend.
602 resend_query(struct reslist *request)
604 if (request->resend == 0)
607 switch(request->type)
610 do_query_number(NULL, NULL, &request->addr, request);
613 do_query_name(NULL, NULL, request->name, request, request->type);
616 /* didn't work, try A */
617 if (request->state == REQ_AAAA)
618 do_query_name(NULL, NULL, request->name, request, T_A);
624 /** Process the answer for a lookup request.
625 * @param[in] request DNS request that got an answer.
626 * @param[in] header Header of DNS response.
627 * @param[in] buf DNS response body.
628 * @param[in] eob Pointer to end of DNS response.
629 * @return Number of answers read from \a buf.
632 proc_answer(struct reslist *request, HEADER* header, char* buf, char* eob)
634 char hostbuf[HOSTLEN + 100]; /* working buffer */
635 unsigned char *current; /* current position in buf */
636 int type; /* answer type */
637 int n; /* temp count */
640 current = (unsigned char *)buf + sizeof(HEADER);
642 for (; header->qdcount > 0; --header->qdcount)
644 if ((n = irc_dn_skipname(current, (unsigned char *)eob)) < 0)
647 current += (size_t) n + QFIXEDSZ;
651 * process each answer sent to us blech.
653 while (header->ancount > 0 && (char *)current < eob)
657 n = irc_dn_expand((unsigned char *)buf, (unsigned char *)eob, current,
658 hostbuf, sizeof(hostbuf));
670 * no more answers left
675 hostbuf[HOSTLEN] = '\0';
677 /* With Address arithmetic you have to be very anal
678 * this code was not working on alpha due to that
679 * (spotted by rodder/jailbird/dianora)
681 current += (size_t) n;
683 if (!(((char *)current + ANSWER_FIXED_SIZE) < eob))
686 type = irc_ns_get16(current);
687 current += TYPE_SIZE;
689 /* We do not use the class or TTL values. */
690 current += CLASS_SIZE;
693 rd_length = irc_ns_get16(current);
694 current += RDLENGTH_SIZE;
697 * Wait to set request->type until we verify this structure
702 if (request->type != T_A)
706 * check for invalid rd_length or too many addresses
708 if (rd_length != sizeof(struct in_addr))
710 memset(&request->addr, 0, sizeof(request->addr));
711 memcpy(&request->addr.in6_16[6], current, sizeof(struct in_addr));
715 if (request->type != T_AAAA)
717 if (rd_length != sizeof(struct irc_in_addr))
719 memcpy(&request->addr, current, sizeof(struct irc_in_addr));
723 if (request->type != T_PTR)
725 n = irc_dn_expand((unsigned char *)buf, (unsigned char *)eob,
726 current, hostbuf, sizeof(hostbuf));
728 return(0); /* broken message */
730 return(0); /* no more answers left */
732 ircd_strncpy(request->name, hostbuf, HOSTLEN);
736 case T_CNAME: /* first check we already haven't started looking
738 if (request->state == REQ_CNAME)
740 n = irc_dn_expand((unsigned char *)buf, (unsigned char *)eob,
741 current, hostbuf, sizeof(hostbuf));
748 request->state = REQ_CNAME;
749 current += rd_length;
753 /* XXX I'd rather just throw away the entire bogus thing
754 * but its possible its just a broken nameserver with still
755 * valid answers. But lets do some rudimentary logging for now...
757 log_write(LS_RESOLVER, L_ERROR, 0, "irc_res.c bogus type %d", type);
759 if ((char*)current + rd_length >= (char*)current)
760 current += rd_length;
771 /** Read a DNS reply from the nameserver and process it.
772 * @param[in] ev I/O activity event for resolver socket.
775 res_readreply(struct Event *ev)
777 struct irc_sockaddr lsin;
779 char buf[sizeof(HEADER) + MAXPACKET];
781 struct reslist *request = NULL;
785 assert((ev_socket(ev) == &res_socket_v4) || (ev_socket(ev) == &res_socket_v6));
786 sock = ev_socket(ev);
788 if (IO_SUCCESS != os_recvfrom_nonb(s_fd(sock), buf, sizeof(buf), &rc, &lsin)
789 || (rc <= sizeof(HEADER)))
793 * check against possibly fake replies
795 if (!res_ourserver(&lsin))
799 * convert DNS reply reader from Network byte order to CPU byte order.
801 header = (HEADER *)buf;
802 header->ancount = ntohs(header->ancount);
803 header->qdcount = ntohs(header->qdcount);
804 header->nscount = ntohs(header->nscount);
805 header->arcount = ntohs(header->arcount);
808 * response for an id which we have already received an answer for
809 * just ignore this response.
811 if (0 == (request = find_id(header->id)))
814 if ((header->rcode != NO_ERRORS) || (header->ancount == 0))
816 if (SERVFAIL == header->rcode || NXDOMAIN == header->rcode)
819 * If a bad error was returned, we stop here and don't send
820 * send any more (no retries granted).
822 Debug((DEBUG_DNS, "Request %p has bad response (state %d type %d rcode %d)", request, request->state, request->type, header->rcode));
823 (*request->callback)(request->callback_ctx, NULL, NULL);
824 rem_request(request);
829 * If we haven't already tried this, and we're looking up AAAA, try A
833 if (request->state == REQ_AAAA && request->type == T_AAAA)
835 request->timeout += feature_int(FEAT_IRCD_RES_TIMEOUT);
836 resend_query(request);
838 else if (request->type == T_PTR && request->state != REQ_INT &&
839 !irc_in_addr_is_ipv4(&request->addr))
841 request->state = REQ_INT;
842 request->timeout += feature_int(FEAT_IRCD_RES_TIMEOUT);
843 resend_query(request);
850 * If this fails there was an error decoding the received packet,
851 * try it again and hope it works the next time.
853 answer_count = proc_answer(request, header, buf, buf + rc);
857 if (request->type == T_PTR)
859 if (request->name == NULL)
862 * got a PTR response with no name, something bogus is happening
863 * don't bother trying again, the client address doesn't resolve
865 Debug((DEBUG_DNS, "Request %p PTR had empty name", request));
866 (*request->callback)(request->callback_ctx, NULL, NULL);
867 rem_request(request);
872 * Lookup the 'authoritative' name that we were given for the
876 if (!irc_in_addr_is_ipv4(&request->addr))
877 do_query_name(request->callback, request->callback_ctx, request->name, NULL, T_AAAA);
880 do_query_name(request->callback, request->callback_ctx, request->name, NULL, T_A);
881 Debug((DEBUG_DNS, "Request %p switching to forward resolution", request));
882 rem_request(request);
887 * got a name and address response, client resolved
889 (*request->callback)(request->callback_ctx, &request->addr, request->name);
890 Debug((DEBUG_DNS, "Request %p got forward resolution", request));
891 rem_request(request);
894 else if (!request->sent)
896 /* XXX - we got a response for a query we didn't send with a valid id?
897 * this should never happen, bail here and leave the client unresolved
901 /* XXX don't leak it */
902 Debug((DEBUG_DNS, "Request %p was unexpected(!)", request));
903 rem_request(request);
907 /** Statistics callback to list DNS servers.
908 * @param[in] source_p Client requesting statistics.
909 * @param[in] sd Stats descriptor for request (ignored).
910 * @param[in] param Extra parameter from user (ignored).
913 report_dns_servers(struct Client *source_p, const struct StatDesc *sd, char *param)
918 for (i = 0; i < irc_nscount; i++)
920 ircd_ntoa_r(ipaddr, &irc_nsaddr_list[i].addr);
921 send_reply(source_p, RPL_STATSALINE, ipaddr);
925 /** Report memory usage to a client.
926 * @param[in] sptr Client requesting information.
927 * @return Total memory used by pending requests.
930 cres_mem(struct Client* sptr)
933 struct reslist *request;
934 size_t request_mem = 0;
935 int request_count = 0;
937 if (request_list.next) {
938 for (dlink = request_list.next; dlink != &request_list; dlink = dlink->next) {
939 request = (struct reslist*)dlink;
940 request_mem += sizeof(*request);
942 request_mem += strlen(request->name) + 1;
947 send_reply(sptr, SND_EXPLICIT | RPL_STATSDEBUG,
948 ":Resolver: requests %d(%d)", request_count, request_mem);