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 /** Check for whether the resolver has been initialized yet. */
60 #define resolver_started() (request_list.next != NULL)
62 /** Maximum DNS packet length.
63 * RFC says 512, but we add extra for expanded names.
65 #define MAXPACKET 1024
66 #define AR_TTL 600 /**< TTL in seconds for dns cache entries */
68 /* RFC 1104/1105 wasn't very helpful about what these fields
69 * should be named, so for now, we'll just name them this way.
70 * we probably should look at what named calls them or something.
72 /** Size of TYPE field of a DNS RR header. */
73 #define TYPE_SIZE (size_t)2
74 /** Size of CLASS field of a DNS RR header. */
75 #define CLASS_SIZE (size_t)2
76 /** Size of TTL field of a DNS RR header. */
77 #define TTL_SIZE (size_t)4
78 /** Size of RDLENGTH field of a DNS RR header. */
79 #define RDLENGTH_SIZE (size_t)2
80 /** Size of fixed-format part of a DNS RR header. */
81 #define ANSWER_FIXED_SIZE (TYPE_SIZE + CLASS_SIZE + TTL_SIZE + RDLENGTH_SIZE)
83 /** Current request state. */
86 REQ_IDLE, /**< We're doing not much at all. */
87 REQ_PTR, /**< Looking up a PTR. */
88 REQ_A, /**< Looking up an A, possibly because AAAA failed. */
89 REQ_AAAA, /**< Looking up an AAAA. */
90 REQ_CNAME, /**< We got a CNAME in response, we better get a real answer next. */
91 REQ_INT /**< ip6.arpa failed, falling back to ip6.int. */
94 /** Doubly linked list node. */
97 struct dlink *prev; /**< Previous element in list. */
98 struct dlink *next; /**< Next element in list. */
101 /** A single resolver request.
102 * (Do not be fooled by the "list" in the name.)
106 struct dlink node; /**< Doubly linked list node. */
107 int id; /**< Request ID (from request header). */
108 int sent; /**< Number of requests sent. */
109 request_state state; /**< State the resolver machine is in. */
110 char type; /**< Current request type. */
111 char retries; /**< Retry counter. */
112 char sends; /**< Number of sends (>1 means resent). */
113 char resend; /**< Send flag; 0 == don't resend. */
114 time_t sentat; /**< Timestamp we last sent this request. */
115 time_t timeout; /**< When this request times out. */
116 struct irc_in_addr addr; /**< Address for this request. */
117 char *name; /**< Hostname for this request. */
118 struct DNSQuery query; /**< Query callback for this request. */
121 /** Base of request list. */
122 static struct dlink request_list;
124 static void rem_request(struct reslist *request);
125 static struct reslist *make_request(const struct DNSQuery *query);
126 static void do_query_name(const struct DNSQuery *query,
127 const char* name, struct reslist *request, int);
128 static void do_query_number(const struct DNSQuery *query,
129 const struct irc_in_addr *,
130 struct reslist *request);
131 static void query_name(const char *name, int query_class, int query_type,
132 struct reslist *request);
133 static int send_res_msg(const char *buf, int len, int count);
134 static void resend_query(struct reslist *request);
135 static int proc_answer(struct reslist *request, HEADER *header, char *, char *);
136 static struct reslist *find_id(int id);
137 static struct DNSReply *make_dnsreply(struct reslist *request);
138 static void res_readreply(struct Event *ev);
139 static void timeout_resolver(struct Event *notused);
141 extern struct irc_sockaddr irc_nsaddr_list[IRCD_MAXNS];
142 extern int irc_nscount;
143 extern char irc_domain[HOSTLEN];
145 /** Check whether \a inp is a nameserver we use.
146 * @param[in] inp Nameserver address.
147 * @return Non-zero if we trust \a inp; zero if not.
150 res_ourserver(const struct irc_sockaddr *inp)
154 for (ns = 0; ns < irc_nscount; ns++)
155 if (!irc_in_addr_cmp(&inp->addr, &irc_nsaddr_list[ns].addr)
156 && inp->port == irc_nsaddr_list[ns].port)
162 /** Start (or re-start) resolver.
163 * This means read resolv.conf, initialize the list of pending
164 * requests, open the resolver socket and initialize its timeout.
167 restart_resolver(void)
171 if (!request_list.next)
172 request_list.next = request_list.prev = &request_list;
174 if (!s_active(&res_socket_v4))
176 int fd = os_socket(&VirtualHost_v4, SOCK_DGRAM, "Resolver UDPv4 socket");
178 socket_add(&res_socket_v4, res_readreply, NULL,
179 SS_DATAGRAM, SOCK_EVENT_READABLE, fd);
182 if (!s_active(&res_socket_v6))
184 int fd = os_socket(&VirtualHost_v6, SOCK_DGRAM, "Resolver UDPv6 socket");
186 socket_add(&res_socket_v6, res_readreply, NULL,
187 SS_DATAGRAM, SOCK_EVENT_READABLE, fd);
190 if (s_active(&res_socket_v4) || s_active(&res_socket_v6))
191 timer_init(&res_timeout);
194 /** Append local domain to hostname if needed.
195 * If \a hname does not contain any '.'s, append #irc_domain to it.
196 * @param[in,out] hname Hostname to check.
197 * @param[in] size Length of \a hname buffer.
200 add_local_domain(char* hname, size_t size)
202 /* try to fix up unqualified names
204 if (strchr(hname, '.') == NULL)
208 size_t len = strlen(hname);
210 if ((strlen(irc_domain) + len + 2) < size)
213 strcpy(hname + len, irc_domain);
219 /** Add a node to a doubly linked list.
220 * @param[in,out] node Node to add to list.
221 * @param[in,out] next Add \a node before this one.
224 add_dlink(struct dlink *node, struct dlink *next)
226 node->prev = next->prev;
228 node->prev->next = node;
229 node->next->prev = node;
232 /** Remove a request from the list and free it.
233 * @param[in] request Node to free.
236 rem_request(struct reslist *request)
238 /* remove from dlist */
239 request->node.prev->next = request->node.next;
240 request->node.next->prev = request->node.prev;
242 MyFree(request->name);
246 /** Create a DNS request record for the server.
247 * @param[in] query Callback information for caller.
248 * @return Newly allocated and linked-in reslist.
250 static struct reslist *
251 make_request(const struct DNSQuery* query)
253 struct reslist *request;
255 if (!resolver_started())
258 request = (struct reslist *)MyMalloc(sizeof(struct reslist));
259 memset(request, 0, sizeof(struct reslist));
261 request->state = REQ_IDLE;
262 request->sentat = CurrentTime;
263 request->retries = feature_int(FEAT_IRCD_RES_RETRIES);
265 request->timeout = feature_int(FEAT_IRCD_RES_TIMEOUT);
266 memset(&request->addr, 0, sizeof(request->addr));
267 memcpy(&request->query, query, sizeof(request->query));
269 add_dlink(&request->node, &request_list);
273 /** Make sure that a timeout event will happen by the given time.
274 * @param[in] when Latest time for timeout to run.
277 check_resolver_timeout(time_t when)
279 if (when > CurrentTime + AR_TTL)
280 when = CurrentTime + AR_TTL;
281 /* TODO after 2.10.12: Rewrite the timer API because there should be
282 * no need for clients to know this kind of implementation detail. */
283 if (when > t_expire(&res_timeout))
285 else if (t_onqueue(&res_timeout) && !(res_timeout.t_header.gh_flags & GEN_MARKED))
286 timer_chg(&res_timeout, TT_ABSOLUTE, when);
288 timer_add(&res_timeout, timeout_resolver, NULL, TT_ABSOLUTE, when);
291 /** Drop pending DNS lookups which have timed out.
292 * @param[in] ev Timer event data (ignored).
295 timeout_resolver(struct Event *ev)
297 struct dlink *ptr, *next_ptr;
298 struct reslist *request;
299 time_t next_time = 0;
302 if (ev_type(ev) != ET_EXPIRE)
305 for (ptr = request_list.next; ptr != &request_list; ptr = next_ptr)
307 next_ptr = ptr->next;
308 request = (struct reslist*)ptr;
309 timeout = request->sentat + request->timeout;
311 if (CurrentTime >= timeout)
313 if (--request->retries <= 0)
315 Debug((DEBUG_DNS, "Request %p out of retries; destroying", request));
316 (*request->query.callback)(request->query.vptr, 0);
317 rem_request(request);
322 request->sentat = CurrentTime;
323 request->timeout += request->timeout;
324 resend_query(request);
328 if ((next_time == 0) || timeout < next_time)
334 if (next_time <= CurrentTime)
335 next_time = CurrentTime + AR_TTL;
336 check_resolver_timeout(next_time);
339 /** Drop queries that are associated with a particular pointer.
340 * This is used to clean up lookups for clients or conf blocks
342 * @param[in] vptr User callback pointer to search for.
345 delete_resolver_queries(const void *vptr)
347 struct dlink *ptr, *next_ptr;
348 struct reslist *request;
350 if (request_list.next) {
351 for (ptr = request_list.next; ptr != &request_list; ptr = next_ptr)
353 next_ptr = ptr->next;
354 request = (struct reslist*)ptr;
355 if (vptr == request->query.vptr) {
356 Debug((DEBUG_DNS, "Removing request %p with vptr %p", request, vptr));
357 rem_request(request);
363 /** Send a message to all of our nameservers.
364 * @param[in] msg Message to send.
365 * @param[in] len Length of message.
366 * @param[in] rcount Maximum number of servers to ask.
367 * @return Number of servers that were successfully asked.
370 send_res_msg(const char *msg, int len, int rcount)
374 int max_queries = IRCD_MIN(irc_nscount, rcount);
376 /* RES_PRIMARY option is not implemented
377 * if (res.options & RES_PRIMARY || 0 == max_queries)
379 if (max_queries == 0)
382 for (i = 0; i < max_queries; i++) {
383 int fd = irc_in_addr_is_ipv4(&irc_nsaddr_list[i].addr) ? s_fd(&res_socket_v4) : s_fd(&res_socket_v6);
384 if (os_sendto_nonb(fd, msg, len, NULL, 0, &irc_nsaddr_list[i]) == IO_SUCCESS)
391 /** Find a DNS request by ID.
392 * @param[in] id Identifier to find.
393 * @return Matching DNS request, or NULL if none are found.
395 static struct reslist *
399 struct reslist *request;
401 for (ptr = request_list.next; ptr != &request_list; ptr = ptr->next)
403 request = (struct reslist*)ptr;
405 if (request->id == id) {
406 Debug((DEBUG_DNS, "find_id(%d) -> %p", id, request));
411 Debug((DEBUG_DNS, "find_id(%d) -> NULL", id));
415 /** Try to look up address for a hostname, trying IPv6 (T_AAAA) first.
416 * @param[in] name Hostname to look up.
417 * @param[in] query Callback information.
420 gethost_byname(const char *name, const struct DNSQuery *query)
422 do_query_name(query, name, NULL, T_AAAA);
425 /** Try to look up hostname for an address.
426 * @param[in] addr Address to look up.
427 * @param[in] query Callback information.
430 gethost_byaddr(const struct irc_in_addr *addr, const struct DNSQuery *query)
432 do_query_number(query, addr, NULL);
435 /** Send a query to look up the address for a name.
436 * @param[in] query Callback information.
437 * @param[in] name Hostname to look up.
438 * @param[in] request DNS lookup structure (may be NULL).
439 * @param[in] type Preferred request type.
442 do_query_name(const struct DNSQuery *query, const char *name,
443 struct reslist *request, int type)
445 char host_name[HOSTLEN + 1];
447 ircd_strncpy(host_name, name, HOSTLEN);
448 add_local_domain(host_name, HOSTLEN);
452 request = make_request(query);
453 DupString(request->name, host_name);
456 request->state = REQ_AAAA;
459 request->state = REQ_A;
462 request->type = type;
463 Debug((DEBUG_DNS, "Requesting DNS %s %s as %p", (request->state == REQ_AAAA ? "AAAA" : "A"), host_name, request));
464 query_name(host_name, C_IN, type, request);
467 /** Send a query to look up the name for an address.
468 * @param[in] query Callback information.
469 * @param[in] addr Address to look up.
470 * @param[in] request DNS lookup structure (may be NULL).
473 do_query_number(const struct DNSQuery *query, const struct irc_in_addr *addr,
474 struct reslist *request)
477 const unsigned char *cp;
479 if (irc_in_addr_is_ipv4(addr))
481 cp = (const unsigned char*)&addr->in6_16[6];
482 ircd_snprintf(NULL, ipbuf, sizeof(ipbuf), "%u.%u.%u.%u.in-addr.arpa.",
483 (unsigned int)(cp[3]), (unsigned int)(cp[2]),
484 (unsigned int)(cp[1]), (unsigned int)(cp[0]));
490 if (request != NULL && request->state == REQ_INT)
495 cp = (const unsigned char *)&addr->in6_16[0];
496 ircd_snprintf(NULL, ipbuf, sizeof(ipbuf),
497 "%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x."
498 "%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.%x.ip6.%s.",
499 (unsigned int)(cp[15]&0xf), (unsigned int)(cp[15]>>4),
500 (unsigned int)(cp[14]&0xf), (unsigned int)(cp[14]>>4),
501 (unsigned int)(cp[13]&0xf), (unsigned int)(cp[13]>>4),
502 (unsigned int)(cp[12]&0xf), (unsigned int)(cp[12]>>4),
503 (unsigned int)(cp[11]&0xf), (unsigned int)(cp[11]>>4),
504 (unsigned int)(cp[10]&0xf), (unsigned int)(cp[10]>>4),
505 (unsigned int)(cp[9]&0xf), (unsigned int)(cp[9]>>4),
506 (unsigned int)(cp[8]&0xf), (unsigned int)(cp[8]>>4),
507 (unsigned int)(cp[7]&0xf), (unsigned int)(cp[7]>>4),
508 (unsigned int)(cp[6]&0xf), (unsigned int)(cp[6]>>4),
509 (unsigned int)(cp[5]&0xf), (unsigned int)(cp[5]>>4),
510 (unsigned int)(cp[4]&0xf), (unsigned int)(cp[4]>>4),
511 (unsigned int)(cp[3]&0xf), (unsigned int)(cp[3]>>4),
512 (unsigned int)(cp[2]&0xf), (unsigned int)(cp[2]>>4),
513 (unsigned int)(cp[1]&0xf), (unsigned int)(cp[1]>>4),
514 (unsigned int)(cp[0]&0xf), (unsigned int)(cp[0]>>4), intarpa);
518 request = make_request(query);
519 request->state= REQ_PTR;
520 request->type = T_PTR;
521 memcpy(&request->addr, addr, sizeof(request->addr));
522 request->name = (char *)MyMalloc(HOSTLEN + 1);
524 Debug((DEBUG_DNS, "Requesting DNS PTR %s as %p", ipbuf, request));
525 query_name(ipbuf, C_IN, T_PTR, request);
528 /** Generate a query based on class, type and name.
529 * @param[in] name Domain name to look up.
530 * @param[in] query_class Query class (see RFC 1035).
531 * @param[in] type Query type (see RFC 1035).
532 * @param[in] request DNS request structure.
535 query_name(const char *name, int query_class, int type,
536 struct reslist *request)
541 memset(buf, 0, sizeof(buf));
543 if ((request_len = irc_res_mkquery(name, query_class, type,
544 (unsigned char *)buf, sizeof(buf))) > 0)
546 HEADER *header = (HEADER *)buf;
549 * generate an unique id
550 * NOTE: we don't have to worry about converting this to and from
551 * network byte order, the nameserver does not interpret this value
552 * and returns it unchanged
556 header->id = (header->id + ircrandom()) & 0xffff;
557 } while (find_id(header->id));
558 request->id = header->id;
561 request->sent += send_res_msg(buf, request_len, request->sends);
562 check_resolver_timeout(request->sentat + request->timeout);
566 /** Send a failed DNS lookup request again.
567 * @param[in] request Request to resend.
570 resend_query(struct reslist *request)
572 if (request->resend == 0)
575 switch(request->type)
578 do_query_number(NULL, &request->addr, request);
581 do_query_name(NULL, request->name, request, request->type);
584 /* didn't work, try A */
585 if (request->state == REQ_AAAA)
586 do_query_name(NULL, request->name, request, T_A);
592 /** Process the answer for a lookup request.
593 * @param[in] request DNS request that got an answer.
594 * @param[in] header Header of DNS response.
595 * @param[in] buf DNS response body.
596 * @param[in] eob Pointer to end of DNS response.
597 * @return Number of answers read from \a buf.
600 proc_answer(struct reslist *request, HEADER* header, char* buf, char* eob)
602 char hostbuf[HOSTLEN + 100]; /* working buffer */
603 unsigned char *current; /* current position in buf */
604 int query_class; /* answer class */
605 int type; /* answer type */
606 int n; /* temp count */
609 current = (unsigned char *)buf + sizeof(HEADER);
611 for (; header->qdcount > 0; --header->qdcount)
613 if ((n = irc_dn_skipname(current, (unsigned char *)eob)) < 0)
616 current += (size_t) n + QFIXEDSZ;
620 * process each answer sent to us blech.
622 while (header->ancount > 0 && (char *)current < eob)
626 n = irc_dn_expand((unsigned char *)buf, (unsigned char *)eob, current,
627 hostbuf, sizeof(hostbuf));
639 * no more answers left
644 hostbuf[HOSTLEN] = '\0';
646 /* With Address arithmetic you have to be very anal
647 * this code was not working on alpha due to that
648 * (spotted by rodder/jailbird/dianora)
650 current += (size_t) n;
652 if (!(((char *)current + ANSWER_FIXED_SIZE) < eob))
655 type = irc_ns_get16(current);
656 current += TYPE_SIZE;
658 query_class = irc_ns_get16(current);
659 current += CLASS_SIZE;
663 rd_length = irc_ns_get16(current);
664 current += RDLENGTH_SIZE;
667 * Wait to set request->type until we verify this structure
672 if (request->type != T_A)
676 * check for invalid rd_length or too many addresses
678 if (rd_length != sizeof(struct in_addr))
680 memset(&request->addr, 0, sizeof(request->addr));
681 memcpy(&request->addr.in6_16[6], current, sizeof(struct in_addr));
685 if (request->type != T_AAAA)
687 if (rd_length != sizeof(struct irc_in_addr))
689 memcpy(&request->addr, current, sizeof(struct irc_in_addr));
693 if (request->type != T_PTR)
695 n = irc_dn_expand((unsigned char *)buf, (unsigned char *)eob,
696 current, hostbuf, sizeof(hostbuf));
698 return(0); /* broken message */
700 return(0); /* no more answers left */
702 ircd_strncpy(request->name, hostbuf, HOSTLEN);
706 case T_CNAME: /* first check we already haven't started looking
708 if (request->type != T_PTR)
711 if (request->state == REQ_CNAME)
713 n = irc_dn_expand((unsigned char *)buf, (unsigned char *)eob,
714 current, hostbuf, sizeof(hostbuf));
721 request->state = REQ_CNAME;
722 current += rd_length;
726 /* XXX I'd rather just throw away the entire bogus thing
727 * but its possible its just a broken nameserver with still
728 * valid answers. But lets do some rudimentary logging for now...
730 log_write(LS_RESOLVER, L_ERROR, 0, "irc_res.c bogus type %d", type);
732 if ((char*)current + rd_length >= (char*)current)
733 current += rd_length;
744 /** Read a DNS reply from the nameserver and process it.
745 * @param[in] ev I/O activity event for resolver socket.
748 res_readreply(struct Event *ev)
750 struct irc_sockaddr lsin;
752 char buf[sizeof(HEADER) + MAXPACKET];
754 struct reslist *request = NULL;
755 struct DNSReply *reply = NULL;
759 assert((ev_socket(ev) == &res_socket_v4) || (ev_socket(ev) == &res_socket_v6));
760 sock = ev_socket(ev);
762 if (IO_SUCCESS != os_recvfrom_nonb(s_fd(sock), buf, sizeof(buf), &rc, &lsin)
763 || (rc <= sizeof(HEADER)))
767 * check against possibly fake replies
769 if (!res_ourserver(&lsin))
773 * convert DNS reply reader from Network byte order to CPU byte order.
775 header = (HEADER *)buf;
776 header->ancount = ntohs(header->ancount);
777 header->qdcount = ntohs(header->qdcount);
778 header->nscount = ntohs(header->nscount);
779 header->arcount = ntohs(header->arcount);
782 * response for an id which we have already received an answer for
783 * just ignore this response.
785 if (0 == (request = find_id(header->id)))
788 if ((header->rcode != NO_ERRORS) || (header->ancount == 0))
790 if (SERVFAIL == header->rcode)
791 resend_query(request);
795 * If we haven't already tried this, and we're looking up AAAA, try A
799 if (request->state == REQ_AAAA && request->type == T_AAAA)
801 request->timeout += feature_int(FEAT_IRCD_RES_TIMEOUT);
802 resend_query(request);
804 else if (request->type == T_PTR && request->state != REQ_INT &&
805 !irc_in_addr_is_ipv4(&request->addr))
807 request->state = REQ_INT;
808 request->timeout += feature_int(FEAT_IRCD_RES_TIMEOUT);
809 resend_query(request);
814 * If a bad error was returned, we stop here and don't send
815 * send any more (no retries granted).
817 Debug((DEBUG_DNS, "Request %p has bad response (state %d type %d rcode %d)", request, request->state, request->type, header->rcode));
818 (*request->query.callback)(request->query.vptr, 0);
819 rem_request(request);
826 * If this fails there was an error decoding the received packet,
827 * try it again and hope it works the next time.
829 answer_count = proc_answer(request, header, buf, buf + rc);
833 if (request->type == T_PTR)
835 if (request->name == NULL)
838 * got a PTR response with no name, something bogus is happening
839 * don't bother trying again, the client address doesn't resolve
841 Debug((DEBUG_DNS, "Request %p PTR had empty name", request));
842 (*request->query.callback)(request->query.vptr, reply);
843 rem_request(request);
848 * Lookup the 'authoritative' name that we were given for the
852 if (!irc_in_addr_is_ipv4(&request->addr))
853 do_query_name(&request->query, request->name, NULL, T_AAAA);
856 do_query_name(&request->query, request->name, NULL, T_A);
857 Debug((DEBUG_DNS, "Request %p switching to forward resolution", request));
858 rem_request(request);
863 * got a name and address response, client resolved
865 reply = make_dnsreply(request);
866 (*request->query.callback)(request->query.vptr, (reply) ? reply : 0);
867 Debug((DEBUG_DNS, "Request %p got forward resolution", request));
868 rem_request(request);
871 else if (!request->sent)
873 /* XXX - we got a response for a query we didn't send with a valid id?
874 * this should never happen, bail here and leave the client unresolved
878 /* XXX don't leak it */
879 Debug((DEBUG_DNS, "Request %p was unexpected(!)", request));
880 rem_request(request);
884 /** Build a DNSReply for a completed request.
885 * @param[in] request Completed DNS request.
886 * @return Newly allocated DNSReply containing host name and address.
888 static struct DNSReply *
889 make_dnsreply(struct reslist *request)
892 assert(request != 0);
894 cp = (struct DNSReply *)MyMalloc(sizeof(struct DNSReply));
896 DupString(cp->h_name, request->name);
897 memcpy(&cp->addr, &request->addr, sizeof(cp->addr));
901 /** Statistics callback to list DNS servers.
902 * @param[in] source_p Client requesting statistics.
903 * @param[in] sd Stats descriptor for request (ignored).
904 * @param[in] param Extra parameter from user (ignored).
907 report_dns_servers(struct Client *source_p, const struct StatDesc *sd, char *param)
912 for (i = 0; i < irc_nscount; i++)
914 ircd_ntoa_r(ipaddr, &irc_nsaddr_list[i].addr);
915 send_reply(source_p, RPL_STATSALINE, ipaddr);
919 /** Report memory usage to a client.
920 * @param[in] sptr Client requesting information.
921 * @return Total memory used by pending requests.
924 cres_mem(struct Client* sptr)
927 struct reslist *request;
928 size_t request_mem = 0;
929 int request_count = 0;
931 if (request_list.next) {
932 for (dlink = request_list.next; dlink != &request_list; dlink = dlink->next) {
933 request = (struct reslist*)dlink;
934 request_mem += sizeof(*request);
936 request_mem += strlen(request->name) + 1;
941 send_reply(sptr, SND_EXPLICIT | RPL_STATSDEBUG,
942 ":Resolver: requests %d(%d)", request_count, request_mem);