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root/svn/ircd-hybrid/trunk/src/res.c

Comparing ircd-hybrid/trunk/src/res.c (file contents):
Revision 3347 by michael, Sun Apr 20 14:03:06 2014 UTC vs.
Revision 4449 by michael, Mon Aug 11 15:46:56 2014 UTC

#	Line 25 | Line 25
25		*/
26
27		/*
28	<	* A rewrite of Darren Reeds original res.c As there is nothing
29	<	* left of Darrens original code, this is now licensed by the hybrid group.
28	>	* A rewrite of Darren Reed's original res.c As there is nothing
29	>	* left of Darren's original code, this is now licensed by the hybrid group.
30		* (Well, some of the function names are the same, and bits of the structs..)
31		* You can use it where it is useful, free even. Buy us a beer and stuff.
32		*
33		* The authors takes no responsibility for any damage or loss
34		* of property which results from the use of this software.
35		*
36	–	* $Id$
37	–	*
36		* July 1999 - Rewrote a bunch of stuff here. Change hostent builder code,
37		*     added callbacks and reference counting of returned hostents.
38		*     --Bleep (Thomas Helvey <tomh@inxpress.net>)
39		*
40		* This was all needlessly complicated for irc. Simplified. No more hostent
41	<	* All we really care about is the IP -> hostname mappings. Thats all.
41	>	* All we really care about is the IP -> hostname mappings. That's all.
42		*
43		* Apr 28, 2003 --cryogen and Dianora
44		*/
#	Line 69 | Line 67
67
68		static PF res_readreply;
69
70	<	#define MAXPACKET      1024  /* rfc sez 512 but we expand names so ... */
71	<	#define RES_MAXALIASES 35    /* maximum aliases allowed */
74	<	#define RES_MAXADDRS   35    /* maximum addresses allowed */
75	<	#define AR_TTL         600   /* TTL in seconds for dns cache entries */
70	>	#define MAXPACKET      1024  /**< rfc says 512 but we expand names so ... */
71	>	#define AR_TTL         600   /**< TTL in seconds for dns cache entries */
72
73	<	/* RFC 1104/1105 wasn't very helpful about what these fields
73	>	/*
74	>	* RFC 1104/1105 wasn't very helpful about what these fields
75		* should be named, so for now, we'll just name them this way.
76	<	* we probably should look at what named calls them or something.
76	>	* We probably should look at what named calls them or something.
77		*/
78		#define TYPE_SIZE         (size_t)2
79		#define CLASS_SIZE        (size_t)2
#	Line 86 | Line 83 | static PF res_readreply;
83
84		typedef enum
85		{
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	<	#ifdef IPV6
90	<	REQ_AAAA,  /* Looking up an AAAA */
94	<	#endif
95	<	REQ_CNAME  /* We got a CNAME in response, we better get a real answer next */
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		} request_state;
92
93		struct reslist
94		{
95	<	dlink_node node;
96	<	int id;
97	<	int sent;                /* number of requests sent */
98	<	request_state state;     /* State the resolver machine is in */
99	<	time_t ttl;
100	<	char type;
101	<	char retries;            /* retry counter */
102	<	unsigned int sends;      /* number of sends (>1 means resent) */
103	<	char resend;             /* send flag. 0 == dont resend */
104	<	time_t sentat;
105	<	time_t timeout;
106	<	struct irc_ssaddr addr;
107	<	char *name;
108	<	dns_callback_fnc callback;
114	<	void *callback_ctx;
95	>	dlink_node node;                           /**< Doubly linked list node. */
96	>	int id;                                    /**< Request ID (from request header). */
97	>	int sent;                                  /**< Number of requests sent */
98	>	request_state state;                       /**< State the resolver machine is in */
99	>	char type;                                 /**< Current request type. */
100	>	char retries;                              /**< Retry counter */
101	>	unsigned int sends;                        /**< Number of sends (>1 means resent). */
102	>	time_t sentat;                             /**< Timestamp we last sent this request. */
103	>	time_t timeout;                            /**< When this request times out. */
104	>	struct irc_ssaddr addr;                    /**< Address for this request. */
105	>	char name[RFC1035_MAX_DOMAIN_LENGTH + 1];  /**< Hostname for this request. */
106	>	size_t namelength;                         /**< Actual hostname length. */
107	>	dns_callback_fnc callback;                 /**< Callback function on completion. */
108	>	void *callback_ctx;                        /**< Context pointer for callback. */
109		};
110
111		static fde_t ResolverFileDescriptor;
112		static dlink_list request_list;
113		static mp_pool_t *dns_pool;
114
121	–	static void rem_request(struct reslist *);
122	–	static struct reslist *make_request(dns_callback_fnc, void *);
123	–	static void do_query_name(dns_callback_fnc, void *,
124	–	const char *, struct reslist *, int);
125	–	static void do_query_number(dns_callback_fnc, void *,
126	–	const struct irc_ssaddr *,
127	–	struct reslist *);
128	–	static void query_name(const char *, int, int, struct reslist *);
129	–	static int send_res_msg(const char *, int, unsigned int);
130	–	static void resend_query(struct reslist *);
131	–	static int proc_answer(struct reslist *, HEADER *, char *, char *);
132	–	static struct reslist *find_id(int);
115
116	+	/*
117	+	* rem_request - remove a request from the list.
118	+	* This must also free any memory that has been allocated for
119	+	* temporary storage of DNS results.
120	+	*/
121	+	static void
122	+	rem_request(struct reslist *request)
123	+	{
124	+	dlinkDelete(&request->node, &request_list);
125	+	mp_pool_release(request);
126	+	}
127	+
128	+	/*
129	+	* make_request - Create a DNS request record for the server.
130	+	*/
131	+	static struct reslist *
132	+	make_request(dns_callback_fnc callback, void *ctx)
133	+	{
134	+	struct reslist *request = mp_pool_get(dns_pool);
135	+
136	+	request->sentat       = CurrentTime;
137	+	request->retries      = 2;
138	+	request->timeout      = 4;  /* Start at 4 and exponential inc. */
139	+	request->state        = REQ_IDLE;
140	+	request->callback     = callback;
141	+	request->callback_ctx = ctx;
142	+
143	+	dlinkAdd(request, &request->node, &request_list);
144	+	return request;
145	+	}
146
147		/*
148		* int
#	Line 146 | Line 158 | static struct reslist *find_id(int);
158		static int
159		res_ourserver(const struct irc_ssaddr *inp)
160		{
149	–	#ifdef IPV6
161		const struct sockaddr_in6 *v6;
162		const struct sockaddr_in6 *v6in = (const struct sockaddr_in6 *)inp;
152	–	#endif
163		const struct sockaddr_in *v4;
164		const struct sockaddr_in *v4in = (const struct sockaddr_in *)inp;
165
166		for (unsigned int i = 0; i < irc_nscount; ++i)
167		{
168		const struct irc_ssaddr *srv = &irc_nsaddr_list[i];
159	–	#ifdef IPV6
169		v6 = (const struct sockaddr_in6 *)srv;
161	–	#endif
170		v4 = (const struct sockaddr_in *)srv;
171
172	<	/* could probably just memcmp(srv, inp, srv.ss_len) here
172	>	/*
173	>	* Could probably just memcmp(srv, inp, srv.ss_len) here
174		* but we'll air on the side of caution - stu
166	–	*
175		*/
176		switch (srv->ss.ss_family)
177		{
170	–	#ifdef IPV6
178		case AF_INET6:
179		if (srv->ss.ss_family == inp->ss.ss_family)
180		if (v6->sin6_port == v6in->sin6_port)
#	Line 175 | Line 182 | res_ourserver(const struct irc_ssaddr *i
182		sizeof(struct in6_addr)))
183		return 1;
184		break;
178	–	#endif
185		case AF_INET:
186		if (srv->ss.ss_family == inp->ss.ss_family)
187		if (v4->sin_port == v4in->sin_port)
#	Line 191 | Line 197 | res_ourserver(const struct irc_ssaddr *i
197		}
198
199		/*
194	–	* timeout_query_list - Remove queries from the list which have been
195	–	* there too long without being resolved.
196	–	*/
197	–	static time_t
198	–	timeout_query_list(time_t now)
199	–	{
200	–	dlink_node *ptr = NULL, *ptr_next = NULL;
201	–	struct reslist *request;
202	–	time_t next_time = 0;
203	–	time_t timeout   = 0;
204	–
205	–	DLINK_FOREACH_SAFE(ptr, ptr_next, request_list.head)
206	–	{
207	–	request = ptr->data;
208	–	timeout = request->sentat + request->timeout;
209	–
210	–	if (now >= timeout)
211	–	{
212	–	if (--request->retries <= 0)
213	–	{
214	–	(*request->callback)(request->callback_ctx, NULL, NULL);
215	–	rem_request(request);
216	–	continue;
217	–	}
218	–	else
219	–	{
220	–	request->sentat = now;
221	–	request->timeout += request->timeout;
222	–	resend_query(request);
223	–	}
224	–	}
225	–
226	–	if ((next_time == 0) || timeout < next_time)
227	–	next_time = timeout;
228	–	}
229	–
230	–	return (next_time > now) ? next_time : (now + AR_TTL);
231	–	}
232	–
233	–	/*
234	–	* timeout_resolver - check request list
235	–	*/
236	–	static void
237	–	timeout_resolver(void *notused)
238	–	{
239	–	timeout_query_list(CurrentTime);
240	–	}
241	–
242	–	/*
200		* start_resolver - do everything we need to read the resolv.conf file
201		* and initialize the resolver file descriptor if needed
202		*/
#	Line 251 | Line 208 | start_resolver(void)
208		if (!ResolverFileDescriptor.flags.open)
209		{
210		if (comm_open(&ResolverFileDescriptor, irc_nsaddr_list[0].ss.ss_family,
211	<	SOCK_DGRAM, 0, "Resolver socket") == -1)
211	>	SOCK_DGRAM, 0, "UDP resolver socket") == -1)
212		return;
213
214		/* At the moment, the resolver FD data is global .. */
215		comm_setselect(&ResolverFileDescriptor, COMM_SELECT_READ, res_readreply, NULL, 0);
259	–	eventAdd("timeout_resolver", timeout_resolver, NULL, 1);
216		}
217		}
218
219		/*
264	–	* init_resolver - initialize resolver and resolver library
265	–	*/
266	–	void
267	–	init_resolver(void)
268	–	{
269	–	dns_pool = mp_pool_new(sizeof(struct reslist), MP_CHUNK_SIZE_DNS);
270	–	memset(&ResolverFileDescriptor, 0, sizeof(fde_t));
271	–	start_resolver();
272	–	}
273	–
274	–	/*
220		* restart_resolver - reread resolv.conf, reopen socket
221		*/
222		void
223		restart_resolver(void)
224		{
225		fd_close(&ResolverFileDescriptor);
281	–	eventDelete(timeout_resolver, NULL);
226		start_resolver();
227		}
228
229		/*
286	–	* rem_request - remove a request from the list.
287	–	* This must also free any memory that has been allocated for
288	–	* temporary storage of DNS results.
289	–	*/
290	–	static void
291	–	rem_request(struct reslist *request)
292	–	{
293	–	dlinkDelete(&request->node, &request_list);
294	–
295	–	MyFree(request->name);
296	–	mp_pool_release(request);
297	–	}
298	–
299	–	/*
300	–	* make_request - Create a DNS request record for the server.
301	–	*/
302	–	static struct reslist *
303	–	make_request(dns_callback_fnc callback, void *ctx)
304	–	{
305	–	struct reslist *request = mp_pool_get(dns_pool);
306	–
307	–	memset(request, 0, sizeof(*request));
308	–	request->sentat       = CurrentTime;
309	–	request->retries      = 2;
310	–	request->resend       = 1;
311	–	request->timeout      = 4;  /* Start at 4 and exponential inc. */
312	–	request->state        = REQ_IDLE;
313	–	request->callback     = callback;
314	–	request->callback_ctx = ctx;
315	–
316	–	dlinkAdd(request, &request->node, &request_list);
317	–	return request;
318	–	}
319	–
320	–	/*
230		* delete_resolver_queries - cleanup outstanding queries
231		* for which there no longer exist clients or conf lines.
232		*/
#	Line 339 | Line 248 | delete_resolver_queries(const void *vptr
248		* send_res_msg - sends msg to all nameservers found in the "_res" structure.
249		* This should reflect /etc/resolv.conf. We will get responses
250		* which arent needed but is easier than checking to see if nameserver
251	<	* isnt present. Returns number of messages successfully sent to
251	>	* isn't present. Returns number of messages successfully sent to
252		* nameservers or -1 if no successful sends.
253		*/
254		static int
#	Line 385 | Line 294 | find_id(int id)
294		}
295
296		/*
297	<	* gethost_byname_type - get host address from name
389	<	*
297	>	* query_name - generate a query based on class, type and name.
298		*/
299	<	void
300	<	gethost_byname_type(dns_callback_fnc callback, void *ctx, const char *name, int type)
299	>	static void
300	>	query_name(const char *name, int query_class, int type,
301	>	struct reslist *request)
302		{
303	<	assert(name);
304	<	do_query_name(callback, ctx, name, NULL, type);
396	<	}
303	>	char buf[MAXPACKET];
304	>	int request_len = 0;
305
306	<	/*
399	<	* gethost_byname - wrapper for _type - send T_AAAA first if IPV6 supported
400	<	*/
401	<	void
402	<	gethost_byname(dns_callback_fnc callback, void *ctx, const char *name)
403	<	{
404	<	#ifdef IPV6
405	<	gethost_byname_type(callback, ctx, name, T_AAAA);
406	<	#else
407	<	gethost_byname_type(callback, ctx, name, T_A);
408	<	#endif
409	<	}
306	>	memset(buf, 0, sizeof(buf));
307
308	<	/*
309	<	* gethost_byaddr - get host name from address
310	<	*/
311	<	void
312	<	gethost_byaddr(dns_callback_fnc callback, void *ctx, const struct irc_ssaddr *addr)
313	<	{
314	<	do_query_number(callback, ctx, addr, NULL);
308	>	if ((request_len = irc_res_mkquery(name, query_class, type,
309	>	(unsigned char *)buf, sizeof(buf))) > 0)
310	>	{
311	>	HEADER *header = (HEADER *)buf;
312	>
313	>	/*
314	>	* Generate an unique id.
315	>	* NOTE: we don't have to worry about converting this to and from
316	>	* network byte order, the nameserver does not interpret this value
317	>	* and returns it unchanged.
318	>	*/
319	>	do
320	>	header->id = (header->id + genrand_int32()) & 0xFFFF;
321	>	while (find_id(header->id));
322	>
323	>	request->id = header->id;
324	>	++request->sends;
325	>
326	>	request->sent += send_res_msg(buf, request_len, request->sends);
327	>	}
328		}
329
330		/*
#	Line 424 | Line 334 | static void
334		do_query_name(dns_callback_fnc callback, void *ctx, const char *name,
335		struct reslist *request, int type)
336		{
337	<	char host_name[HOSTLEN + 1];
337	>	char host_name[RFC1035_MAX_DOMAIN_LENGTH + 1];
338
339		strlcpy(host_name, name, sizeof(host_name));
340
341		if (request == NULL)
342		{
343	<	request       = make_request(callback, ctx);
344	<	request->name = MyMalloc(strlen(host_name) + 1);
345	<	request->type = type;
436	<	strcpy(request->name, host_name);
437	<	#ifdef IPV6
438	<	if (type != T_A)
439	<	request->state = REQ_AAAA;
440	<	else
441	<	#endif
442	<	request->state = REQ_A;
343	>	request             = make_request(callback, ctx);
344	>	request->type       = type;
345	>	request->namelength = strlcpy(request->name, host_name, sizeof(request->name));
346		}
347
348		request->type = type;
#	Line 465 | Line 368 | do_query_number(dns_callback_fnc callbac
368		(unsigned int)(cp[3]), (unsigned int)(cp[2]),
369		(unsigned int)(cp[1]), (unsigned int)(cp[0]));
370		}
468	–	#ifdef IPV6
371		else if (addr->ss.ss_family == AF_INET6)
372		{
373		const struct sockaddr_in6 *v6 = (const struct sockaddr_in6 *)addr;
#	Line 491 | Line 393 | do_query_number(dns_callback_fnc callbac
393		(unsigned int)(cp[1] & 0xf), (unsigned int)(cp[1] >> 4),
394		(unsigned int)(cp[0] & 0xf), (unsigned int)(cp[0] >> 4));
395		}
396	<	#endif
396	>
397		if (request == NULL)
398		{
399		request       = make_request(callback, ctx);
400		request->type = T_PTR;
401		memcpy(&request->addr, addr, sizeof(struct irc_ssaddr));
500	–	request->name = MyMalloc(HOSTLEN + 1);
402		}
403
404		query_name(ipbuf, C_IN, T_PTR, request);
405		}
406
407		/*
408	<	* query_name - generate a query based on class, type and name.
408	>	* gethost_byname_type - get host address from name
409	>	*
410		*/
411	<	static void
412	<	query_name(const char *name, int query_class, int type,
511	<	struct reslist *request)
411	>	void
412	>	gethost_byname_type(dns_callback_fnc callback, void *ctx, const char *name, int type)
413		{
414	<	char buf[MAXPACKET];
415	<	int request_len = 0;
416	<
516	<	memset(buf, 0, sizeof(buf));
517	<
518	<	if ((request_len = irc_res_mkquery(name, query_class, type,
519	<	(unsigned char *)buf, sizeof(buf))) > 0)
520	<	{
521	<	HEADER *header = (HEADER *)buf;
522	<
523	<	/*
524	<	* generate an unique id
525	<	* NOTE: we don't have to worry about converting this to and from
526	<	* network byte order, the nameserver does not interpret this value
527	<	* and returns it unchanged
528	<	*/
529	<	do
530	<	header->id = (header->id + genrand_int32()) & 0xffff;
531	<	while (find_id(header->id));
414	>	assert(name);
415	>	do_query_name(callback, ctx, name, NULL, type);
416	>	}
417
418	<	request->id = header->id;
419	<	++request->sends;
418	>	/*
419	>	* gethost_byname - wrapper for _type - send T_AAAA first if IPV6 supported
420	>	*/
421	>	void
422	>	gethost_byname(dns_callback_fnc callback, void *ctx, const char *name)
423	>	{
424	>	gethost_byname_type(callback, ctx, name, T_AAAA);
425	>	}
426
427	<	request->sent += send_res_msg(buf, request_len, request->sends);
428	<	}
427	>	/*
428	>	* gethost_byaddr - get host name from address
429	>	*/
430	>	void
431	>	gethost_byaddr(dns_callback_fnc callback, void *ctx, const struct irc_ssaddr *addr)
432	>	{
433	>	do_query_number(callback, ctx, addr, NULL);
434		}
435
436		static void
437		resend_query(struct reslist *request)
438		{
543	–	if (request->resend == 0)
544	–	return;
545	–
439		switch (request->type)
440		{
441		case T_PTR:
442		do_query_number(NULL, NULL, &request->addr, request);
443		break;
444		case T_A:
445	+	case T_AAAA:
446		do_query_name(NULL, NULL, request->name, request, request->type);
447		break;
554	–	#ifdef IPV6
555	–	case T_AAAA:
556	–	/* didnt work, try A */
557	–	if (request->state == REQ_AAAA)
558	–	do_query_name(NULL, NULL, request->name, request, T_A);
559	–	#endif
448		default:
449		break;
450		}
#	Line 568 | Line 456 | resend_query(struct reslist *request)
456		static int
457		proc_answer(struct reslist *request, HEADER *header, char *buf, char *eob)
458		{
459	<	char hostbuf[HOSTLEN + 100]; /* working buffer */
459	>	char hostbuf[RFC1035_MAX_DOMAIN_LENGTH + 100]; /* working buffer */
460		unsigned char *current;      /* current position in buf */
573	–	int query_class;             /* answer class */
461		int type;                    /* answer type */
462		int n;                       /* temp count */
463		int rd_length;
464		struct sockaddr_in *v4;      /* conversion */
578	–	#ifdef IPV6
465		struct sockaddr_in6 *v6;
466	<	#endif
466	>
467		current = (unsigned char *)buf + sizeof(HEADER);
468
469		for (; header->qdcount > 0; --header->qdcount)
#	Line 589 | Line 475 | proc_answer(struct reslist *request, HEA
475		}
476
477		/*
478	<	* process each answer sent to us blech.
478	>	* Process each answer sent to us blech.
479		*/
480		while (header->ancount > 0 && (char *)current < eob)
481		{
#	Line 598 | Line 484 | proc_answer(struct reslist *request, HEA
484		n = irc_dn_expand((unsigned char *)buf, (unsigned char *)eob, current,
485		hostbuf, sizeof(hostbuf));
486
487	<	if (n < 0 /* Broken message */ || n == 0 /* No more answers left */)
487	>	if (n < 0  /* Broken message */ || n == 0  /* No more answers left */)
488		return 0;
489
490	<	hostbuf[HOSTLEN] = '\0';
490	>	hostbuf[RFC1035_MAX_DOMAIN_LENGTH] = '\0';
491
492	<	/* With Address arithmetic you have to be very anal
492	>	/*
493	>	* With Address arithmetic you have to be very anal
494		* this code was not working on alpha due to that
495		* (spotted by rodder/jailbird/dianora)
496		*/
#	Line 614 | Line 501 | proc_answer(struct reslist *request, HEA
501
502		type = irc_ns_get16(current);
503		current += TYPE_SIZE;
617	–
618	–	query_class = irc_ns_get16(current);
504		current += CLASS_SIZE;
620	–
621	–	request->ttl = irc_ns_get32(current);
505		current += TTL_SIZE;
623	–
506		rd_length = irc_ns_get16(current);
507		current += RDLENGTH_SIZE;
508
#	Line 645 | Line 527 | proc_answer(struct reslist *request, HEA
527		memcpy(&v4->sin_addr, current, sizeof(struct in_addr));
528		return 1;
529		break;
648	–	#ifdef IPV6
530		case T_AAAA:
531		if (request->type != T_AAAA)
532		return 0;
#	Line 659 | Line 540 | proc_answer(struct reslist *request, HEA
540		memcpy(&v6->sin6_addr, current, sizeof(struct in6_addr));
541		return 1;
542		break;
662	–	#endif
543		case T_PTR:
544		if (request->type != T_PTR)
545		return 0;
546
547		n = irc_dn_expand((unsigned char *)buf, (unsigned char *)eob,
548		current, hostbuf, sizeof(hostbuf));
549	<	if (n < 0 /* Broken message */ || n == 0 /* No more answers left */)
549	>	if (n < 0  /* Broken message */ || n == 0  /* No more answers left */)
550		return 0;
551
552	<	strlcpy(request->name, hostbuf, HOSTLEN + 1);
552	>	request->namelength = strlcpy(request->name, hostbuf, sizeof(request->name));
553		return 1;
554		break;
555	<	case T_CNAME: /* first check we already havent started looking
676	<	into a cname */
555	>	case T_CNAME:  /* First check we already haven't started looking into a cname */
556		if (request->type != T_PTR)
557		return 0;
558
#	Line 710 | Line 589 | proc_answer(struct reslist *request, HEA
589		static void
590		res_readreply(fde_t *fd, void *data)
591		{
592	<	char buf[sizeof(HEADER) + MAXPACKET]
714	<	/* Sparc and alpha need 16bit-alignment for accessing header->id
715	<	* (which is uint16_t). Because of the header = (HEADER*) buf;
716	<	* lateron, this is neeeded. --FaUl
717	<	*/
718	<	#if defined(__sparc__) || defined(__alpha__)
719	<	__attribute__((aligned (16)))
720	<	#endif
721	<	;
592	>	char buf[sizeof(HEADER) + MAXPACKET];
593		HEADER *header;
594		struct reslist *request = NULL;
595	<	int rc;
595	>	ssize_t rc = 0;
596		socklen_t len = sizeof(struct irc_ssaddr);
597		struct irc_ssaddr lsin;
598
599	<	rc = recvfrom(fd->fd, buf, sizeof(buf), 0, (struct sockaddr *)&lsin, &len);
600	<
601	<	/* Re-schedule a read *after* recvfrom, or we'll be registering
602	<	* interest where it'll instantly be ready for read :-) -- adrian
732	<	*/
733	<	comm_setselect(fd, COMM_SELECT_READ, res_readreply, NULL, 0);
734	<
735	<	/* Better to cast the sizeof instead of rc */
736	<	if (rc <= (int)(sizeof(HEADER)))
737	<	return;
599	>	while ((rc = recvfrom(fd->fd, buf, sizeof(buf), 0, (struct sockaddr *)&lsin, &len)) != -1)
600	>	{
601	>	if (rc <= (ssize_t)sizeof(HEADER))
602	>	continue;
603
604	<	/*
605	<	* Convert DNS reply reader from Network byte order to CPU byte order.
606	<	*/
607	<	header = (HEADER *)buf;
608	<	header->ancount = ntohs(header->ancount);
744	<	header->qdcount = ntohs(header->qdcount);
745	<	header->nscount = ntohs(header->nscount);
746	<	header->arcount = ntohs(header->arcount);
604	>	/*
605	>	* Check against possibly fake replies
606	>	*/
607	>	if (!res_ourserver(&lsin))
608	>	continue;
609
610	<	/*
611	<	* Check against possibly fake replies
612	<	*/
613	<	if (!res_ourserver(&lsin))
614	<	return;
610	>	/*
611	>	* Convert DNS reply reader from Network byte order to CPU byte order.
612	>	*/
613	>	header = (HEADER *)buf;
614	>	header->ancount = ntohs(header->ancount);
615	>	header->qdcount = ntohs(header->qdcount);
616	>	header->nscount = ntohs(header->nscount);
617	>	header->arcount = ntohs(header->arcount);
618
619	<	/*
620	<	* Response for an id which we have already received an answer for
621	<	* just ignore this response.
622	<	*/
623	<	if (!(request = find_id(header->id)))
624	<	return;
619	>	/*
620	>	* Response for an id which we have already received an answer for
621	>	* just ignore this response.
622	>	*/
623	>	if ((request = find_id(header->id)) == NULL)
624	>	continue;
625
626	<	if ((header->rcode != NO_ERRORS) || (header->ancount == 0))
762	<	{
763	<	if (header->rcode == SERVFAIL || header->rcode == NXDOMAIN)
626	>	if (header->rcode != NO_ERRORS || header->ancount == 0)
627		{
628		/*
629		* If a bad error was returned, stop here and don't
630		* send any more (no retries granted).
631		*/
632	<	(*request->callback)(request->callback_ctx, NULL, NULL);
632	>	(*request->callback)(request->callback_ctx, NULL, NULL, 0);
633		rem_request(request);
634	+	continue;
635		}
636	<	#ifdef IPV6
637	<	else
636	>
637	>	/*
638	>	* If this fails there was an error decoding the received packet.
639	>	* We only give it one shot. If it fails, just leave the client
640	>	* unresolved.
641	>	*/
642	>	if (!proc_answer(request, header, buf, buf + rc))
643		{
644	<	/*
645	<	* If we havent already tried this, and we're looking up AAAA, try A
646	<	* now
778	<	*/
779	<	if (request->state == REQ_AAAA && request->type == T_AAAA)
780	<	{
781	<	request->timeout += 4;
782	<	resend_query(request);
783	<	}
644	>	(*request->callback)(request->callback_ctx, NULL, NULL, 0);
645	>	rem_request(request);
646	>	continue;
647		}
785	–	#endif
786	–
787	–	return;
788	–	}
648
790	–	/*
791	–	* If this fails there was an error decoding the received packet,
792	–	* try it again and hope it works the next time.
793	–	*/
794	–	if (proc_answer(request, header, buf, buf + rc))
795	–	{
649		if (request->type == T_PTR)
650		{
651	<	if (request->name == NULL)
651	>	if (request->namelength == 0)
652		{
653		/*
654		* Got a PTR response with no name, something bogus is happening
655		* don't bother trying again, the client address doesn't resolve
656		*/
657	<	(*request->callback)(request->callback_ctx, NULL, NULL);
657	>	(*request->callback)(request->callback_ctx, NULL, NULL, 0);
658		rem_request(request);
659	<	return;
659	>	continue;
660		}
661
662		/*
663		* Lookup the 'authoritative' name that we were given for the ip#.
664		*/
812	–	#ifdef IPV6
665		if (request->addr.ss.ss_family == AF_INET6)
666		gethost_byname_type(request->callback, request->callback_ctx, request->name, T_AAAA);
667		else
668	<	#endif
817	<	gethost_byname_type(request->callback, request->callback_ctx, request->name, T_A);
668	>	gethost_byname_type(request->callback, request->callback_ctx, request->name, T_A);
669		rem_request(request);
670		}
671		else
#	Line 822 | Line 673 | res_readreply(fde_t *fd, void *data)
673		/*
674		* Got a name and address response, client resolved
675		*/
676	<	(*request->callback)(request->callback_ctx, &request->addr, request->name);
676	>	(*request->callback)(request->callback_ctx, &request->addr, request->name, request->namelength);
677		rem_request(request);
678		}
828	–	}
829	–	else if (!request->sent)
830	–	{
831	–	/* XXX - we got a response for a query we didn't send with a valid id?
832	–	* this should never happen, bail here and leave the client unresolved
833	–	*/
834	–	assert(0);
679
680	<	/* XXX don't leak it */
837	<	rem_request(request);
680	>	continue;
681		}
682	+
683	+	comm_setselect(fd, COMM_SELECT_READ, res_readreply, NULL, 0);
684		}
685
686		void
#	Line 851 | Line 696 | report_dns_servers(struct Client *source
696		sendto_one_numeric(source_p, &me, RPL_STATSALINE, ipaddr);
697		}
698		}
699	+
700	+	/*
701	+	* timeout_query_list - Remove queries from the list which have been
702	+	* there too long without being resolved.
703	+	*/
704	+	static time_t
705	+	timeout_query_list(void)
706	+	{
707	+	dlink_node *ptr = NULL, *ptr_next = NULL;
708	+	struct reslist *request = NULL;
709	+	time_t next_time = 0;
710	+	time_t timeout   = 0;
711	+
712	+	DLINK_FOREACH_SAFE(ptr, ptr_next, request_list.head)
713	+	{
714	+	request = ptr->data;
715	+	timeout = request->sentat + request->timeout;
716	+
717	+	if (CurrentTime >= timeout)
718	+	{
719	+	if (--request->retries <= 0)
720	+	{
721	+	(*request->callback)(request->callback_ctx, NULL, NULL, 0);
722	+	rem_request(request);
723	+	continue;
724	+	}
725	+	else
726	+	{
727	+	request->sentat = CurrentTime;
728	+	request->timeout += request->timeout;
729	+	resend_query(request);
730	+	}
731	+	}
732	+
733	+	if (next_time == 0 || timeout < next_time)
734	+	next_time = timeout;
735	+	}
736	+
737	+	return (next_time > CurrentTime) ? next_time : (CurrentTime + AR_TTL);
738	+	}
739	+
740	+	/*
741	+	* timeout_resolver - check request list
742	+	*/
743	+	static void
744	+	timeout_resolver(void *unused)
745	+	{
746	+	timeout_query_list();
747	+	}
748	+
749	+	/*
750	+	* init_resolver - initialize resolver and resolver library
751	+	*/
752	+	void
753	+	init_resolver(void)
754	+	{
755	+	static struct event event_timeout_resolver =
756	+	{
757	+	.name = "timeout_resolver",
758	+	.handler = timeout_resolver,
759	+	.when = 1
760	+	};
761	+
762	+	dns_pool = mp_pool_new(sizeof(struct reslist), MP_CHUNK_SIZE_DNS);
763	+
764	+	start_resolver();
765	+	event_add(&event_timeout_resolver, NULL);
766	+	}

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