xref: /freebsd/contrib/unbound/util/netevent.c (revision 38f0b757fd84d17d0fc24739a7cda160c4516d81)
1 /*
2  * util/netevent.c - event notification
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 LIMITED
25  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE
27  * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33  * POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 /**
37  * \file
38  *
39  * This file contains event notification functions.
40  */
41 #include "config.h"
42 #include <ldns/wire2host.h>
43 #include "util/netevent.h"
44 #include "util/log.h"
45 #include "util/net_help.h"
46 #include "util/fptr_wlist.h"
47 #ifdef HAVE_OPENSSL_SSL_H
48 #include <openssl/ssl.h>
49 #endif
50 #ifdef HAVE_OPENSSL_ERR_H
51 #include <openssl/err.h>
52 #endif
53 
54 /* -------- Start of local definitions -------- */
55 /** if CMSG_ALIGN is not defined on this platform, a workaround */
56 #ifndef CMSG_ALIGN
57 #  ifdef _CMSG_DATA_ALIGN
58 #    define CMSG_ALIGN _CMSG_DATA_ALIGN
59 #  else
60 #    define CMSG_ALIGN(len) (((len)+sizeof(long)-1) & ~(sizeof(long)-1))
61 #  endif
62 #endif
63 
64 /** if CMSG_LEN is not defined on this platform, a workaround */
65 #ifndef CMSG_LEN
66 #  define CMSG_LEN(len) (CMSG_ALIGN(sizeof(struct cmsghdr))+(len))
67 #endif
68 
69 /** if CMSG_SPACE is not defined on this platform, a workaround */
70 #ifndef CMSG_SPACE
71 #  ifdef _CMSG_HDR_ALIGN
72 #    define CMSG_SPACE(l) (CMSG_ALIGN(l)+_CMSG_HDR_ALIGN(sizeof(struct cmsghdr)))
73 #  else
74 #    define CMSG_SPACE(l) (CMSG_ALIGN(l)+CMSG_ALIGN(sizeof(struct cmsghdr)))
75 #  endif
76 #endif
77 
78 /** The TCP reading or writing query timeout in seconds */
79 #define TCP_QUERY_TIMEOUT 120
80 
81 #ifndef NONBLOCKING_IS_BROKEN
82 /** number of UDP reads to perform per read indication from select */
83 #define NUM_UDP_PER_SELECT 100
84 #else
85 #define NUM_UDP_PER_SELECT 1
86 #endif
87 
88 /* We define libevent structures here to hide the libevent stuff. */
89 
90 #ifdef USE_MINI_EVENT
91 #  ifdef USE_WINSOCK
92 #    include "util/winsock_event.h"
93 #  else
94 #    include "util/mini_event.h"
95 #  endif /* USE_WINSOCK */
96 #else /* USE_MINI_EVENT */
97    /* we use libevent */
98 #  ifdef HAVE_EVENT_H
99 #    include <event.h>
100 #  else
101 #    include "event2/event.h"
102 #    include "event2/event_struct.h"
103 #    include "event2/event_compat.h"
104 #  endif
105 #endif /* USE_MINI_EVENT */
106 
107 /**
108  * The internal event structure for keeping libevent info for the event.
109  * Possibly other structures (list, tree) this is part of.
110  */
111 struct internal_event {
112 	/** the comm base */
113 	struct comm_base* base;
114 	/** libevent event type, alloced here */
115 	struct event ev;
116 };
117 
118 /**
119  * Internal base structure, so that every thread has its own events.
120  */
121 struct internal_base {
122 	/** libevent event_base type. */
123 	struct event_base* base;
124 	/** seconds time pointer points here */
125 	uint32_t secs;
126 	/** timeval with current time */
127 	struct timeval now;
128 	/** the event used for slow_accept timeouts */
129 	struct event slow_accept;
130 	/** true if slow_accept is enabled */
131 	int slow_accept_enabled;
132 };
133 
134 /**
135  * Internal timer structure, to store timer event in.
136  */
137 struct internal_timer {
138 	/** the comm base */
139 	struct comm_base* base;
140 	/** libevent event type, alloced here */
141 	struct event ev;
142 	/** is timer enabled */
143 	uint8_t enabled;
144 };
145 
146 /**
147  * Internal signal structure, to store signal event in.
148  */
149 struct internal_signal {
150 	/** libevent event type, alloced here */
151 	struct event ev;
152 	/** next in signal list */
153 	struct internal_signal* next;
154 };
155 
156 /** create a tcp handler with a parent */
157 static struct comm_point* comm_point_create_tcp_handler(
158 	struct comm_base *base, struct comm_point* parent, size_t bufsize,
159         comm_point_callback_t* callback, void* callback_arg);
160 
161 /* -------- End of local definitions -------- */
162 
163 #ifdef USE_MINI_EVENT
164 /** minievent updates the time when it blocks. */
165 #define comm_base_now(x) /* nothing to do */
166 #else /* !USE_MINI_EVENT */
167 /** fillup the time values in the event base */
168 static void
169 comm_base_now(struct comm_base* b)
170 {
171 	if(gettimeofday(&b->eb->now, NULL) < 0) {
172 		log_err("gettimeofday: %s", strerror(errno));
173 	}
174 	b->eb->secs = (uint32_t)b->eb->now.tv_sec;
175 }
176 #endif /* USE_MINI_EVENT */
177 
178 struct comm_base*
179 comm_base_create(int sigs)
180 {
181 	struct comm_base* b = (struct comm_base*)calloc(1,
182 		sizeof(struct comm_base));
183 	if(!b)
184 		return NULL;
185 	b->eb = (struct internal_base*)calloc(1, sizeof(struct internal_base));
186 	if(!b->eb) {
187 		free(b);
188 		return NULL;
189 	}
190 #ifdef USE_MINI_EVENT
191 	(void)sigs;
192 	/* use mini event time-sharing feature */
193 	b->eb->base = event_init(&b->eb->secs, &b->eb->now);
194 #else
195 #  if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
196 	/* libev */
197 	if(sigs)
198 		b->eb->base=(struct event_base *)ev_default_loop(EVFLAG_AUTO);
199 	else
200 		b->eb->base=(struct event_base *)ev_loop_new(EVFLAG_AUTO);
201 #  else
202 	(void)sigs;
203 #    ifdef HAVE_EVENT_BASE_NEW
204 	b->eb->base = event_base_new();
205 #    else
206 	b->eb->base = event_init();
207 #    endif
208 #  endif
209 #endif
210 	if(!b->eb->base) {
211 		free(b->eb);
212 		free(b);
213 		return NULL;
214 	}
215 	comm_base_now(b);
216 	/* avoid event_get_method call which causes crashes even when
217 	 * not printing, because its result is passed */
218 	verbose(VERB_ALGO,
219 #if defined(HAVE_EV_LOOP) || defined(HAVE_EV_DEFAULT_LOOP)
220 		"libev"
221 #elif defined(USE_MINI_EVENT)
222 		"event "
223 #else
224 		"libevent "
225 #endif
226 		"%s uses %s method.",
227 		event_get_version(),
228 #ifdef HAVE_EVENT_BASE_GET_METHOD
229 		event_base_get_method(b->eb->base)
230 #else
231 		"not_obtainable"
232 #endif
233 	);
234 	return b;
235 }
236 
237 void
238 comm_base_delete(struct comm_base* b)
239 {
240 	if(!b)
241 		return;
242 	if(b->eb->slow_accept_enabled) {
243 		if(event_del(&b->eb->slow_accept) != 0) {
244 			log_err("could not event_del slow_accept");
245 		}
246 	}
247 #ifdef USE_MINI_EVENT
248 	event_base_free(b->eb->base);
249 #elif defined(HAVE_EVENT_BASE_FREE) && defined(HAVE_EVENT_BASE_ONCE)
250 	/* only libevent 1.2+ has it, but in 1.2 it is broken -
251 	   assertion fails on signal handling ev that is not deleted
252  	   in libevent 1.3c (event_base_once appears) this is fixed. */
253 	event_base_free(b->eb->base);
254 #endif /* HAVE_EVENT_BASE_FREE and HAVE_EVENT_BASE_ONCE */
255 	b->eb->base = NULL;
256 	free(b->eb);
257 	free(b);
258 }
259 
260 void
261 comm_base_timept(struct comm_base* b, uint32_t** tt, struct timeval** tv)
262 {
263 	*tt = &b->eb->secs;
264 	*tv = &b->eb->now;
265 }
266 
267 void
268 comm_base_dispatch(struct comm_base* b)
269 {
270 	int retval;
271 	retval = event_base_dispatch(b->eb->base);
272 	if(retval != 0) {
273 		fatal_exit("event_dispatch returned error %d, "
274 			"errno is %s", retval, strerror(errno));
275 	}
276 }
277 
278 void comm_base_exit(struct comm_base* b)
279 {
280 	if(event_base_loopexit(b->eb->base, NULL) != 0) {
281 		log_err("Could not loopexit");
282 	}
283 }
284 
285 void comm_base_set_slow_accept_handlers(struct comm_base* b,
286 	void (*stop_acc)(void*), void (*start_acc)(void*), void* arg)
287 {
288 	b->stop_accept = stop_acc;
289 	b->start_accept = start_acc;
290 	b->cb_arg = arg;
291 }
292 
293 struct event_base* comm_base_internal(struct comm_base* b)
294 {
295 	return b->eb->base;
296 }
297 
298 /** see if errno for udp has to be logged or not uses globals */
299 static int
300 udp_send_errno_needs_log(struct sockaddr* addr, socklen_t addrlen)
301 {
302 	/* do not log transient errors (unless high verbosity) */
303 #if defined(ENETUNREACH) || defined(EHOSTDOWN) || defined(EHOSTUNREACH) || defined(ENETDOWN)
304 	switch(errno) {
305 #  ifdef ENETUNREACH
306 		case ENETUNREACH:
307 #  endif
308 #  ifdef EHOSTDOWN
309 		case EHOSTDOWN:
310 #  endif
311 #  ifdef EHOSTUNREACH
312 		case EHOSTUNREACH:
313 #  endif
314 #  ifdef ENETDOWN
315 		case ENETDOWN:
316 #  endif
317 			if(verbosity < VERB_ALGO)
318 				return 0;
319 		default:
320 			break;
321 	}
322 #endif
323 	/* squelch errors where people deploy AAAA ::ffff:bla for
324 	 * authority servers, which we try for intranets. */
325 	if(errno == EINVAL && addr_is_ip4mapped(
326 		(struct sockaddr_storage*)addr, addrlen) &&
327 		verbosity < VERB_DETAIL)
328 		return 0;
329 	/* SO_BROADCAST sockopt can give access to 255.255.255.255,
330 	 * but a dns cache does not need it. */
331 	if(errno == EACCES && addr_is_broadcast(
332 		(struct sockaddr_storage*)addr, addrlen) &&
333 		verbosity < VERB_DETAIL)
334 		return 0;
335 	return 1;
336 }
337 
338 int tcp_connect_errno_needs_log(struct sockaddr* addr, socklen_t addrlen)
339 {
340 	return udp_send_errno_needs_log(addr, addrlen);
341 }
342 
343 /* send a UDP reply */
344 int
345 comm_point_send_udp_msg(struct comm_point *c, ldns_buffer* packet,
346 	struct sockaddr* addr, socklen_t addrlen)
347 {
348 	ssize_t sent;
349 	log_assert(c->fd != -1);
350 #ifdef UNBOUND_DEBUG
351 	if(ldns_buffer_remaining(packet) == 0)
352 		log_err("error: send empty UDP packet");
353 #endif
354 	log_assert(addr && addrlen > 0);
355 	sent = sendto(c->fd, (void*)ldns_buffer_begin(packet),
356 		ldns_buffer_remaining(packet), 0,
357 		addr, addrlen);
358 	if(sent == -1) {
359 		if(!udp_send_errno_needs_log(addr, addrlen))
360 			return 0;
361 #ifndef USE_WINSOCK
362 		verbose(VERB_OPS, "sendto failed: %s", strerror(errno));
363 #else
364 		verbose(VERB_OPS, "sendto failed: %s",
365 			wsa_strerror(WSAGetLastError()));
366 #endif
367 		log_addr(VERB_OPS, "remote address is",
368 			(struct sockaddr_storage*)addr, addrlen);
369 		return 0;
370 	} else if((size_t)sent != ldns_buffer_remaining(packet)) {
371 		log_err("sent %d in place of %d bytes",
372 			(int)sent, (int)ldns_buffer_remaining(packet));
373 		return 0;
374 	}
375 	return 1;
376 }
377 
378 #if defined(AF_INET6) && defined(IPV6_PKTINFO) && (defined(HAVE_RECVMSG) || defined(HAVE_SENDMSG))
379 /** print debug ancillary info */
380 static void p_ancil(const char* str, struct comm_reply* r)
381 {
382 	if(r->srctype != 4 && r->srctype != 6) {
383 		log_info("%s: unknown srctype %d", str, r->srctype);
384 		return;
385 	}
386 	if(r->srctype == 6) {
387 		char buf[1024];
388 		if(inet_ntop(AF_INET6, &r->pktinfo.v6info.ipi6_addr,
389 			buf, (socklen_t)sizeof(buf)) == 0) {
390 			strncpy(buf, "(inet_ntop error)", sizeof(buf));
391 		}
392 		buf[sizeof(buf)-1]=0;
393 		log_info("%s: %s %d", str, buf, r->pktinfo.v6info.ipi6_ifindex);
394 	} else if(r->srctype == 4) {
395 #ifdef IP_PKTINFO
396 		char buf1[1024], buf2[1024];
397 		if(inet_ntop(AF_INET, &r->pktinfo.v4info.ipi_addr,
398 			buf1, (socklen_t)sizeof(buf1)) == 0) {
399 			strncpy(buf1, "(inet_ntop error)", sizeof(buf1));
400 		}
401 		buf1[sizeof(buf1)-1]=0;
402 #ifdef HAVE_STRUCT_IN_PKTINFO_IPI_SPEC_DST
403 		if(inet_ntop(AF_INET, &r->pktinfo.v4info.ipi_spec_dst,
404 			buf2, (socklen_t)sizeof(buf2)) == 0) {
405 			strncpy(buf2, "(inet_ntop error)", sizeof(buf2));
406 		}
407 		buf2[sizeof(buf2)-1]=0;
408 #else
409 		buf2[0]=0;
410 #endif
411 		log_info("%s: %d %s %s", str, r->pktinfo.v4info.ipi_ifindex,
412 			buf1, buf2);
413 #elif defined(IP_RECVDSTADDR)
414 		char buf1[1024];
415 		if(inet_ntop(AF_INET, &r->pktinfo.v4addr,
416 			buf1, (socklen_t)sizeof(buf1)) == 0) {
417 			strncpy(buf1, "(inet_ntop error)", sizeof(buf1));
418 		}
419 		buf1[sizeof(buf1)-1]=0;
420 		log_info("%s: %s", str, buf1);
421 #endif /* IP_PKTINFO or PI_RECVDSTDADDR */
422 	}
423 }
424 #endif /* AF_INET6 && IPV6_PKTINFO && HAVE_RECVMSG||HAVE_SENDMSG */
425 
426 /** send a UDP reply over specified interface*/
427 static int
428 comm_point_send_udp_msg_if(struct comm_point *c, ldns_buffer* packet,
429 	struct sockaddr* addr, socklen_t addrlen, struct comm_reply* r)
430 {
431 #if defined(AF_INET6) && defined(IPV6_PKTINFO) && defined(HAVE_SENDMSG)
432 	ssize_t sent;
433 	struct msghdr msg;
434 	struct iovec iov[1];
435 	char control[256];
436 #ifndef S_SPLINT_S
437 	struct cmsghdr *cmsg;
438 #endif /* S_SPLINT_S */
439 
440 	log_assert(c->fd != -1);
441 #ifdef UNBOUND_DEBUG
442 	if(ldns_buffer_remaining(packet) == 0)
443 		log_err("error: send empty UDP packet");
444 #endif
445 	log_assert(addr && addrlen > 0);
446 
447 	msg.msg_name = addr;
448 	msg.msg_namelen = addrlen;
449 	iov[0].iov_base = ldns_buffer_begin(packet);
450 	iov[0].iov_len = ldns_buffer_remaining(packet);
451 	msg.msg_iov = iov;
452 	msg.msg_iovlen = 1;
453 	msg.msg_control = control;
454 #ifndef S_SPLINT_S
455 	msg.msg_controllen = sizeof(control);
456 #endif /* S_SPLINT_S */
457 	msg.msg_flags = 0;
458 
459 #ifndef S_SPLINT_S
460 	cmsg = CMSG_FIRSTHDR(&msg);
461 	if(r->srctype == 4) {
462 #ifdef IP_PKTINFO
463 		msg.msg_controllen = CMSG_SPACE(sizeof(struct in_pktinfo));
464 		log_assert(msg.msg_controllen <= sizeof(control));
465 		cmsg->cmsg_level = IPPROTO_IP;
466 		cmsg->cmsg_type = IP_PKTINFO;
467 		memmove(CMSG_DATA(cmsg), &r->pktinfo.v4info,
468 			sizeof(struct in_pktinfo));
469 		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo));
470 #elif defined(IP_SENDSRCADDR)
471 		msg.msg_controllen = CMSG_SPACE(sizeof(struct in_addr));
472 		log_assert(msg.msg_controllen <= sizeof(control));
473 		cmsg->cmsg_level = IPPROTO_IP;
474 		cmsg->cmsg_type = IP_SENDSRCADDR;
475 		memmove(CMSG_DATA(cmsg), &r->pktinfo.v4addr,
476 			sizeof(struct in_addr));
477 		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr));
478 #else
479 		verbose(VERB_ALGO, "no IP_PKTINFO or IP_SENDSRCADDR");
480 		msg.msg_control = NULL;
481 #endif /* IP_PKTINFO or IP_SENDSRCADDR */
482 	} else if(r->srctype == 6) {
483 		msg.msg_controllen = CMSG_SPACE(sizeof(struct in6_pktinfo));
484 		log_assert(msg.msg_controllen <= sizeof(control));
485 		cmsg->cmsg_level = IPPROTO_IPV6;
486 		cmsg->cmsg_type = IPV6_PKTINFO;
487 		memmove(CMSG_DATA(cmsg), &r->pktinfo.v6info,
488 			sizeof(struct in6_pktinfo));
489 		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
490 	} else {
491 		/* try to pass all 0 to use default route */
492 		msg.msg_controllen = CMSG_SPACE(sizeof(struct in6_pktinfo));
493 		log_assert(msg.msg_controllen <= sizeof(control));
494 		cmsg->cmsg_level = IPPROTO_IPV6;
495 		cmsg->cmsg_type = IPV6_PKTINFO;
496 		memset(CMSG_DATA(cmsg), 0, sizeof(struct in6_pktinfo));
497 		cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo));
498 	}
499 #endif /* S_SPLINT_S */
500 	if(verbosity >= VERB_ALGO)
501 		p_ancil("send_udp over interface", r);
502 	sent = sendmsg(c->fd, &msg, 0);
503 	if(sent == -1) {
504 		if(!udp_send_errno_needs_log(addr, addrlen))
505 			return 0;
506 		verbose(VERB_OPS, "sendmsg failed: %s", strerror(errno));
507 		log_addr(VERB_OPS, "remote address is",
508 			(struct sockaddr_storage*)addr, addrlen);
509 		return 0;
510 	} else if((size_t)sent != ldns_buffer_remaining(packet)) {
511 		log_err("sent %d in place of %d bytes",
512 			(int)sent, (int)ldns_buffer_remaining(packet));
513 		return 0;
514 	}
515 	return 1;
516 #else
517 	(void)c;
518 	(void)packet;
519 	(void)addr;
520 	(void)addrlen;
521 	(void)r;
522 	log_err("sendmsg: IPV6_PKTINFO not supported");
523 	return 0;
524 #endif /* AF_INET6 && IPV6_PKTINFO && HAVE_SENDMSG */
525 }
526 
527 void
528 comm_point_udp_ancil_callback(int fd, short event, void* arg)
529 {
530 #if defined(AF_INET6) && defined(IPV6_PKTINFO) && defined(HAVE_RECVMSG)
531 	struct comm_reply rep;
532 	struct msghdr msg;
533 	struct iovec iov[1];
534 	ssize_t rcv;
535 	char ancil[256];
536 	int i;
537 #ifndef S_SPLINT_S
538 	struct cmsghdr* cmsg;
539 #endif /* S_SPLINT_S */
540 
541 	rep.c = (struct comm_point*)arg;
542 	log_assert(rep.c->type == comm_udp);
543 
544 	if(!(event&EV_READ))
545 		return;
546 	log_assert(rep.c && rep.c->buffer && rep.c->fd == fd);
547 	comm_base_now(rep.c->ev->base);
548 	for(i=0; i<NUM_UDP_PER_SELECT; i++) {
549 		ldns_buffer_clear(rep.c->buffer);
550 		rep.addrlen = (socklen_t)sizeof(rep.addr);
551 		log_assert(fd != -1);
552 		log_assert(ldns_buffer_remaining(rep.c->buffer) > 0);
553 		msg.msg_name = &rep.addr;
554 		msg.msg_namelen = (socklen_t)sizeof(rep.addr);
555 		iov[0].iov_base = ldns_buffer_begin(rep.c->buffer);
556 		iov[0].iov_len = ldns_buffer_remaining(rep.c->buffer);
557 		msg.msg_iov = iov;
558 		msg.msg_iovlen = 1;
559 		msg.msg_control = ancil;
560 #ifndef S_SPLINT_S
561 		msg.msg_controllen = sizeof(ancil);
562 #endif /* S_SPLINT_S */
563 		msg.msg_flags = 0;
564 		rcv = recvmsg(fd, &msg, 0);
565 		if(rcv == -1) {
566 			if(errno != EAGAIN && errno != EINTR) {
567 				log_err("recvmsg failed: %s", strerror(errno));
568 			}
569 			return;
570 		}
571 		rep.addrlen = msg.msg_namelen;
572 		ldns_buffer_skip(rep.c->buffer, rcv);
573 		ldns_buffer_flip(rep.c->buffer);
574 		rep.srctype = 0;
575 #ifndef S_SPLINT_S
576 		for(cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL;
577 			cmsg = CMSG_NXTHDR(&msg, cmsg)) {
578 			if( cmsg->cmsg_level == IPPROTO_IPV6 &&
579 				cmsg->cmsg_type == IPV6_PKTINFO) {
580 				rep.srctype = 6;
581 				memmove(&rep.pktinfo.v6info, CMSG_DATA(cmsg),
582 					sizeof(struct in6_pktinfo));
583 				break;
584 #ifdef IP_PKTINFO
585 			} else if( cmsg->cmsg_level == IPPROTO_IP &&
586 				cmsg->cmsg_type == IP_PKTINFO) {
587 				rep.srctype = 4;
588 				memmove(&rep.pktinfo.v4info, CMSG_DATA(cmsg),
589 					sizeof(struct in_pktinfo));
590 				break;
591 #elif defined(IP_RECVDSTADDR)
592 			} else if( cmsg->cmsg_level == IPPROTO_IP &&
593 				cmsg->cmsg_type == IP_RECVDSTADDR) {
594 				rep.srctype = 4;
595 				memmove(&rep.pktinfo.v4addr, CMSG_DATA(cmsg),
596 					sizeof(struct in_addr));
597 				break;
598 #endif /* IP_PKTINFO or IP_RECVDSTADDR */
599 			}
600 		}
601 		if(verbosity >= VERB_ALGO)
602 			p_ancil("receive_udp on interface", &rep);
603 #endif /* S_SPLINT_S */
604 		fptr_ok(fptr_whitelist_comm_point(rep.c->callback));
605 		if((*rep.c->callback)(rep.c, rep.c->cb_arg, NETEVENT_NOERROR, &rep)) {
606 			/* send back immediate reply */
607 			(void)comm_point_send_udp_msg_if(rep.c, rep.c->buffer,
608 				(struct sockaddr*)&rep.addr, rep.addrlen, &rep);
609 		}
610 		if(rep.c->fd == -1) /* commpoint closed */
611 			break;
612 	}
613 #else
614 	(void)fd;
615 	(void)event;
616 	(void)arg;
617 	fatal_exit("recvmsg: No support for IPV6_PKTINFO. "
618 		"Please disable interface-automatic");
619 #endif /* AF_INET6 && IPV6_PKTINFO && HAVE_RECVMSG */
620 }
621 
622 void
623 comm_point_udp_callback(int fd, short event, void* arg)
624 {
625 	struct comm_reply rep;
626 	ssize_t rcv;
627 	int i;
628 
629 	rep.c = (struct comm_point*)arg;
630 	log_assert(rep.c->type == comm_udp);
631 
632 	if(!(event&EV_READ))
633 		return;
634 	log_assert(rep.c && rep.c->buffer && rep.c->fd == fd);
635 	comm_base_now(rep.c->ev->base);
636 	for(i=0; i<NUM_UDP_PER_SELECT; i++) {
637 		ldns_buffer_clear(rep.c->buffer);
638 		rep.addrlen = (socklen_t)sizeof(rep.addr);
639 		log_assert(fd != -1);
640 		log_assert(ldns_buffer_remaining(rep.c->buffer) > 0);
641 		rcv = recvfrom(fd, (void*)ldns_buffer_begin(rep.c->buffer),
642 			ldns_buffer_remaining(rep.c->buffer), 0,
643 			(struct sockaddr*)&rep.addr, &rep.addrlen);
644 		if(rcv == -1) {
645 #ifndef USE_WINSOCK
646 			if(errno != EAGAIN && errno != EINTR)
647 				log_err("recvfrom %d failed: %s",
648 					fd, strerror(errno));
649 #else
650 			if(WSAGetLastError() != WSAEINPROGRESS &&
651 				WSAGetLastError() != WSAECONNRESET &&
652 				WSAGetLastError()!= WSAEWOULDBLOCK)
653 				log_err("recvfrom failed: %s",
654 					wsa_strerror(WSAGetLastError()));
655 #endif
656 			return;
657 		}
658 		ldns_buffer_skip(rep.c->buffer, rcv);
659 		ldns_buffer_flip(rep.c->buffer);
660 		rep.srctype = 0;
661 		fptr_ok(fptr_whitelist_comm_point(rep.c->callback));
662 		if((*rep.c->callback)(rep.c, rep.c->cb_arg, NETEVENT_NOERROR, &rep)) {
663 			/* send back immediate reply */
664 			(void)comm_point_send_udp_msg(rep.c, rep.c->buffer,
665 				(struct sockaddr*)&rep.addr, rep.addrlen);
666 		}
667 		if(rep.c->fd != fd) /* commpoint closed to -1 or reused for
668 		another UDP port. Note rep.c cannot be reused with TCP fd. */
669 			break;
670 	}
671 }
672 
673 /** Use a new tcp handler for new query fd, set to read query */
674 static void
675 setup_tcp_handler(struct comm_point* c, int fd)
676 {
677 	log_assert(c->type == comm_tcp);
678 	log_assert(c->fd == -1);
679 	ldns_buffer_clear(c->buffer);
680 	c->tcp_is_reading = 1;
681 	c->tcp_byte_count = 0;
682 	comm_point_start_listening(c, fd, TCP_QUERY_TIMEOUT);
683 }
684 
685 void comm_base_handle_slow_accept(int ATTR_UNUSED(fd),
686 	short ATTR_UNUSED(event), void* arg)
687 {
688 	struct comm_base* b = (struct comm_base*)arg;
689 	/* timeout for the slow accept, re-enable accepts again */
690 	if(b->start_accept) {
691 		verbose(VERB_ALGO, "wait is over, slow accept disabled");
692 		fptr_ok(fptr_whitelist_start_accept(b->start_accept));
693 		(*b->start_accept)(b->cb_arg);
694 		b->eb->slow_accept_enabled = 0;
695 	}
696 }
697 
698 int comm_point_perform_accept(struct comm_point* c,
699 	struct sockaddr_storage* addr, socklen_t* addrlen)
700 {
701 	int new_fd;
702 	*addrlen = (socklen_t)sizeof(*addr);
703 	new_fd = accept(c->fd, (struct sockaddr*)addr, addrlen);
704 	if(new_fd == -1) {
705 #ifndef USE_WINSOCK
706 		/* EINTR is signal interrupt. others are closed connection. */
707 		if(	errno == EINTR || errno == EAGAIN
708 #ifdef EWOULDBLOCK
709 			|| errno == EWOULDBLOCK
710 #endif
711 #ifdef ECONNABORTED
712 			|| errno == ECONNABORTED
713 #endif
714 #ifdef EPROTO
715 			|| errno == EPROTO
716 #endif /* EPROTO */
717 			)
718 			return -1;
719 #if defined(ENFILE) && defined(EMFILE)
720 		if(errno == ENFILE || errno == EMFILE) {
721 			/* out of file descriptors, likely outside of our
722 			 * control. stop accept() calls for some time */
723 			if(c->ev->base->stop_accept) {
724 				struct comm_base* b = c->ev->base;
725 				struct timeval tv;
726 				verbose(VERB_ALGO, "out of file descriptors: "
727 					"slow accept");
728 				b->eb->slow_accept_enabled = 1;
729 				fptr_ok(fptr_whitelist_stop_accept(
730 					b->stop_accept));
731 				(*b->stop_accept)(b->cb_arg);
732 				/* set timeout, no mallocs */
733 				tv.tv_sec = NETEVENT_SLOW_ACCEPT_TIME/1000;
734 				tv.tv_usec = NETEVENT_SLOW_ACCEPT_TIME%1000;
735 				event_set(&b->eb->slow_accept, -1, EV_TIMEOUT,
736 					comm_base_handle_slow_accept, b);
737 				if(event_base_set(b->eb->base,
738 					&b->eb->slow_accept) != 0) {
739 					/* we do not want to log here, because
740 					 * that would spam the logfiles.
741 					 * error: "event_base_set failed." */
742 				}
743 				if(event_add(&b->eb->slow_accept, &tv) != 0) {
744 					/* we do not want to log here,
745 					 * error: "event_add failed." */
746 				}
747 			}
748 			return -1;
749 		}
750 #endif
751 		log_err("accept failed: %s", strerror(errno));
752 #else /* USE_WINSOCK */
753 		if(WSAGetLastError() == WSAEINPROGRESS ||
754 			WSAGetLastError() == WSAECONNRESET)
755 			return -1;
756 		if(WSAGetLastError() == WSAEWOULDBLOCK) {
757 			winsock_tcp_wouldblock(&c->ev->ev, EV_READ);
758 			return -1;
759 		}
760 		log_err("accept failed: %s", wsa_strerror(WSAGetLastError()));
761 #endif
762 		log_addr(0, "remote address is", addr, *addrlen);
763 		return -1;
764 	}
765 	fd_set_nonblock(new_fd);
766 	return new_fd;
767 }
768 
769 #ifdef USE_WINSOCK
770 static long win_bio_cb(BIO *b, int oper, const char* ATTR_UNUSED(argp),
771         int ATTR_UNUSED(argi), long argl, long retvalue)
772 {
773 	verbose(VERB_ALGO, "bio_cb %d, %s %s %s", oper,
774 		(oper&BIO_CB_RETURN)?"return":"before",
775 		(oper&BIO_CB_READ)?"read":((oper&BIO_CB_WRITE)?"write":"other"),
776 		WSAGetLastError()==WSAEWOULDBLOCK?"wsawb":"");
777 	/* on windows, check if previous operation caused EWOULDBLOCK */
778 	if( (oper == (BIO_CB_READ|BIO_CB_RETURN) && argl == 0) ||
779 		(oper == (BIO_CB_GETS|BIO_CB_RETURN) && argl == 0)) {
780 		if(WSAGetLastError() == WSAEWOULDBLOCK)
781 			winsock_tcp_wouldblock((struct event*)
782 				BIO_get_callback_arg(b), EV_READ);
783 	}
784 	if( (oper == (BIO_CB_WRITE|BIO_CB_RETURN) && argl == 0) ||
785 		(oper == (BIO_CB_PUTS|BIO_CB_RETURN) && argl == 0)) {
786 		if(WSAGetLastError() == WSAEWOULDBLOCK)
787 			winsock_tcp_wouldblock((struct event*)
788 				BIO_get_callback_arg(b), EV_WRITE);
789 	}
790 	/* return original return value */
791 	return retvalue;
792 }
793 
794 /** set win bio callbacks for nonblocking operations */
795 void
796 comm_point_tcp_win_bio_cb(struct comm_point* c, void* thessl)
797 {
798 	SSL* ssl = (SSL*)thessl;
799 	/* set them both just in case, but usually they are the same BIO */
800 	BIO_set_callback(SSL_get_rbio(ssl), &win_bio_cb);
801 	BIO_set_callback_arg(SSL_get_rbio(ssl), (char*)&c->ev->ev);
802 	BIO_set_callback(SSL_get_wbio(ssl), &win_bio_cb);
803 	BIO_set_callback_arg(SSL_get_wbio(ssl), (char*)&c->ev->ev);
804 }
805 #endif
806 
807 void
808 comm_point_tcp_accept_callback(int fd, short event, void* arg)
809 {
810 	struct comm_point* c = (struct comm_point*)arg, *c_hdl;
811 	int new_fd;
812 	log_assert(c->type == comm_tcp_accept);
813 	if(!(event & EV_READ)) {
814 		log_info("ignoring tcp accept event %d", (int)event);
815 		return;
816 	}
817 	comm_base_now(c->ev->base);
818 	/* find free tcp handler. */
819 	if(!c->tcp_free) {
820 		log_warn("accepted too many tcp, connections full");
821 		return;
822 	}
823 	/* accept incoming connection. */
824 	c_hdl = c->tcp_free;
825 	log_assert(fd != -1);
826 	new_fd = comm_point_perform_accept(c, &c_hdl->repinfo.addr,
827 		&c_hdl->repinfo.addrlen);
828 	if(new_fd == -1)
829 		return;
830 	if(c->ssl) {
831 		c_hdl->ssl = incoming_ssl_fd(c->ssl, new_fd);
832 		if(!c_hdl->ssl) {
833 			c_hdl->fd = new_fd;
834 			comm_point_close(c_hdl);
835 			return;
836 		}
837 		c_hdl->ssl_shake_state = comm_ssl_shake_read;
838 #ifdef USE_WINSOCK
839 		comm_point_tcp_win_bio_cb(c_hdl, c_hdl->ssl);
840 #endif
841 	}
842 
843 	/* grab the tcp handler buffers */
844 	c->tcp_free = c_hdl->tcp_free;
845 	if(!c->tcp_free) {
846 		/* stop accepting incoming queries for now. */
847 		comm_point_stop_listening(c);
848 	}
849 	/* addr is dropped. Not needed for tcp reply. */
850 	setup_tcp_handler(c_hdl, new_fd);
851 }
852 
853 /** Make tcp handler free for next assignment */
854 static void
855 reclaim_tcp_handler(struct comm_point* c)
856 {
857 	log_assert(c->type == comm_tcp);
858 	if(c->ssl) {
859 #ifdef HAVE_SSL
860 		SSL_shutdown(c->ssl);
861 		SSL_free(c->ssl);
862 		c->ssl = NULL;
863 #endif
864 	}
865 	comm_point_close(c);
866 	if(c->tcp_parent) {
867 		c->tcp_free = c->tcp_parent->tcp_free;
868 		c->tcp_parent->tcp_free = c;
869 		if(!c->tcp_free) {
870 			/* re-enable listening on accept socket */
871 			comm_point_start_listening(c->tcp_parent, -1, -1);
872 		}
873 	}
874 }
875 
876 /** do the callback when writing is done */
877 static void
878 tcp_callback_writer(struct comm_point* c)
879 {
880 	log_assert(c->type == comm_tcp);
881 	ldns_buffer_clear(c->buffer);
882 	if(c->tcp_do_toggle_rw)
883 		c->tcp_is_reading = 1;
884 	c->tcp_byte_count = 0;
885 	/* switch from listening(write) to listening(read) */
886 	comm_point_stop_listening(c);
887 	comm_point_start_listening(c, -1, -1);
888 }
889 
890 /** do the callback when reading is done */
891 static void
892 tcp_callback_reader(struct comm_point* c)
893 {
894 	log_assert(c->type == comm_tcp || c->type == comm_local);
895 	ldns_buffer_flip(c->buffer);
896 	if(c->tcp_do_toggle_rw)
897 		c->tcp_is_reading = 0;
898 	c->tcp_byte_count = 0;
899 	if(c->type == comm_tcp)
900 		comm_point_stop_listening(c);
901 	fptr_ok(fptr_whitelist_comm_point(c->callback));
902 	if( (*c->callback)(c, c->cb_arg, NETEVENT_NOERROR, &c->repinfo) ) {
903 		comm_point_start_listening(c, -1, TCP_QUERY_TIMEOUT);
904 	}
905 }
906 
907 /** continue ssl handshake */
908 #ifdef HAVE_SSL
909 static int
910 ssl_handshake(struct comm_point* c)
911 {
912 	int r;
913 	if(c->ssl_shake_state == comm_ssl_shake_hs_read) {
914 		/* read condition satisfied back to writing */
915 		comm_point_listen_for_rw(c, 1, 1);
916 		c->ssl_shake_state = comm_ssl_shake_none;
917 		return 1;
918 	}
919 	if(c->ssl_shake_state == comm_ssl_shake_hs_write) {
920 		/* write condition satisfied, back to reading */
921 		comm_point_listen_for_rw(c, 1, 0);
922 		c->ssl_shake_state = comm_ssl_shake_none;
923 		return 1;
924 	}
925 
926 	ERR_clear_error();
927 	r = SSL_do_handshake(c->ssl);
928 	if(r != 1) {
929 		int want = SSL_get_error(c->ssl, r);
930 		if(want == SSL_ERROR_WANT_READ) {
931 			if(c->ssl_shake_state == comm_ssl_shake_read)
932 				return 1;
933 			c->ssl_shake_state = comm_ssl_shake_read;
934 			comm_point_listen_for_rw(c, 1, 0);
935 			return 1;
936 		} else if(want == SSL_ERROR_WANT_WRITE) {
937 			if(c->ssl_shake_state == comm_ssl_shake_write)
938 				return 1;
939 			c->ssl_shake_state = comm_ssl_shake_write;
940 			comm_point_listen_for_rw(c, 0, 1);
941 			return 1;
942 		} else if(r == 0) {
943 			return 0; /* closed */
944 		} else if(want == SSL_ERROR_SYSCALL) {
945 			/* SYSCALL and errno==0 means closed uncleanly */
946 			if(errno != 0)
947 				log_err("SSL_handshake syscall: %s",
948 					strerror(errno));
949 			return 0;
950 		} else {
951 			log_crypto_err("ssl handshake failed");
952 			log_addr(1, "ssl handshake failed", &c->repinfo.addr,
953 				c->repinfo.addrlen);
954 			return 0;
955 		}
956 	}
957 	/* this is where peer verification could take place */
958 	log_addr(VERB_ALGO, "SSL DNS connection", &c->repinfo.addr,
959 		c->repinfo.addrlen);
960 
961 	/* setup listen rw correctly */
962 	if(c->tcp_is_reading) {
963 		if(c->ssl_shake_state != comm_ssl_shake_read)
964 			comm_point_listen_for_rw(c, 1, 0);
965 	} else {
966 		comm_point_listen_for_rw(c, 1, 1);
967 	}
968 	c->ssl_shake_state = comm_ssl_shake_none;
969 	return 1;
970 }
971 #endif /* HAVE_SSL */
972 
973 /** ssl read callback on TCP */
974 static int
975 ssl_handle_read(struct comm_point* c)
976 {
977 #ifdef HAVE_SSL
978 	int r;
979 	if(c->ssl_shake_state != comm_ssl_shake_none) {
980 		if(!ssl_handshake(c))
981 			return 0;
982 		if(c->ssl_shake_state != comm_ssl_shake_none)
983 			return 1;
984 	}
985 	if(c->tcp_byte_count < sizeof(uint16_t)) {
986 		/* read length bytes */
987 		ERR_clear_error();
988 		if((r=SSL_read(c->ssl, (void*)ldns_buffer_at(c->buffer,
989 			c->tcp_byte_count), (int)(sizeof(uint16_t) -
990 			c->tcp_byte_count))) <= 0) {
991 			int want = SSL_get_error(c->ssl, r);
992 			if(want == SSL_ERROR_ZERO_RETURN) {
993 				return 0; /* shutdown, closed */
994 			} else if(want == SSL_ERROR_WANT_READ) {
995 				return 1; /* read more later */
996 			} else if(want == SSL_ERROR_WANT_WRITE) {
997 				c->ssl_shake_state = comm_ssl_shake_hs_write;
998 				comm_point_listen_for_rw(c, 0, 1);
999 				return 1;
1000 			} else if(want == SSL_ERROR_SYSCALL) {
1001 				if(errno != 0)
1002 					log_err("SSL_read syscall: %s",
1003 						strerror(errno));
1004 				return 0;
1005 			}
1006 			log_crypto_err("could not SSL_read");
1007 			return 0;
1008 		}
1009 		c->tcp_byte_count += r;
1010 		if(c->tcp_byte_count != sizeof(uint16_t))
1011 			return 1;
1012 		if(ldns_buffer_read_u16_at(c->buffer, 0) >
1013 			ldns_buffer_capacity(c->buffer)) {
1014 			verbose(VERB_QUERY, "ssl: dropped larger than buffer");
1015 			return 0;
1016 		}
1017 		ldns_buffer_set_limit(c->buffer,
1018 			ldns_buffer_read_u16_at(c->buffer, 0));
1019 		if(ldns_buffer_limit(c->buffer) < LDNS_HEADER_SIZE) {
1020 			verbose(VERB_QUERY, "ssl: dropped bogus too short.");
1021 			return 0;
1022 		}
1023 		verbose(VERB_ALGO, "Reading ssl tcp query of length %d",
1024 			(int)ldns_buffer_limit(c->buffer));
1025 	}
1026 	log_assert(ldns_buffer_remaining(c->buffer) > 0);
1027 	ERR_clear_error();
1028 	r = SSL_read(c->ssl, (void*)ldns_buffer_current(c->buffer),
1029 		(int)ldns_buffer_remaining(c->buffer));
1030 	if(r <= 0) {
1031 		int want = SSL_get_error(c->ssl, r);
1032 		if(want == SSL_ERROR_ZERO_RETURN) {
1033 			return 0; /* shutdown, closed */
1034 		} else if(want == SSL_ERROR_WANT_READ) {
1035 			return 1; /* read more later */
1036 		} else if(want == SSL_ERROR_WANT_WRITE) {
1037 			c->ssl_shake_state = comm_ssl_shake_hs_write;
1038 			comm_point_listen_for_rw(c, 0, 1);
1039 			return 1;
1040 		} else if(want == SSL_ERROR_SYSCALL) {
1041 			if(errno != 0)
1042 				log_err("SSL_read syscall: %s",
1043 					strerror(errno));
1044 			return 0;
1045 		}
1046 		log_crypto_err("could not SSL_read");
1047 		return 0;
1048 	}
1049 	ldns_buffer_skip(c->buffer, (ssize_t)r);
1050 	if(ldns_buffer_remaining(c->buffer) <= 0) {
1051 		tcp_callback_reader(c);
1052 	}
1053 	return 1;
1054 #else
1055 	(void)c;
1056 	return 0;
1057 #endif /* HAVE_SSL */
1058 }
1059 
1060 /** ssl write callback on TCP */
1061 static int
1062 ssl_handle_write(struct comm_point* c)
1063 {
1064 #ifdef HAVE_SSL
1065 	int r;
1066 	if(c->ssl_shake_state != comm_ssl_shake_none) {
1067 		if(!ssl_handshake(c))
1068 			return 0;
1069 		if(c->ssl_shake_state != comm_ssl_shake_none)
1070 			return 1;
1071 	}
1072 	/* ignore return, if fails we may simply block */
1073 	(void)SSL_set_mode(c->ssl, SSL_MODE_ENABLE_PARTIAL_WRITE);
1074 	if(c->tcp_byte_count < sizeof(uint16_t)) {
1075 		uint16_t len = htons(ldns_buffer_limit(c->buffer));
1076 		ERR_clear_error();
1077 		r = SSL_write(c->ssl,
1078 			(void*)(((uint8_t*)&len)+c->tcp_byte_count),
1079 			(int)(sizeof(uint16_t)-c->tcp_byte_count));
1080 		if(r <= 0) {
1081 			int want = SSL_get_error(c->ssl, r);
1082 			if(want == SSL_ERROR_ZERO_RETURN) {
1083 				return 0; /* closed */
1084 			} else if(want == SSL_ERROR_WANT_READ) {
1085 				c->ssl_shake_state = comm_ssl_shake_read;
1086 				comm_point_listen_for_rw(c, 1, 0);
1087 				return 1; /* wait for read condition */
1088 			} else if(want == SSL_ERROR_WANT_WRITE) {
1089 				return 1; /* write more later */
1090 			} else if(want == SSL_ERROR_SYSCALL) {
1091 				if(errno != 0)
1092 					log_err("SSL_write syscall: %s",
1093 						strerror(errno));
1094 				return 0;
1095 			}
1096 			log_crypto_err("could not SSL_write");
1097 			return 0;
1098 		}
1099 		c->tcp_byte_count += r;
1100 		if(c->tcp_byte_count < sizeof(uint16_t))
1101 			return 1;
1102 		ldns_buffer_set_position(c->buffer, c->tcp_byte_count -
1103 			sizeof(uint16_t));
1104 		if(ldns_buffer_remaining(c->buffer) == 0) {
1105 			tcp_callback_writer(c);
1106 			return 1;
1107 		}
1108 	}
1109 	log_assert(ldns_buffer_remaining(c->buffer) > 0);
1110 	ERR_clear_error();
1111 	r = SSL_write(c->ssl, (void*)ldns_buffer_current(c->buffer),
1112 		(int)ldns_buffer_remaining(c->buffer));
1113 	if(r <= 0) {
1114 		int want = SSL_get_error(c->ssl, r);
1115 		if(want == SSL_ERROR_ZERO_RETURN) {
1116 			return 0; /* closed */
1117 		} else if(want == SSL_ERROR_WANT_READ) {
1118 			c->ssl_shake_state = comm_ssl_shake_read;
1119 			comm_point_listen_for_rw(c, 1, 0);
1120 			return 1; /* wait for read condition */
1121 		} else if(want == SSL_ERROR_WANT_WRITE) {
1122 			return 1; /* write more later */
1123 		} else if(want == SSL_ERROR_SYSCALL) {
1124 			if(errno != 0)
1125 				log_err("SSL_write syscall: %s",
1126 					strerror(errno));
1127 			return 0;
1128 		}
1129 		log_crypto_err("could not SSL_write");
1130 		return 0;
1131 	}
1132 	ldns_buffer_skip(c->buffer, (ssize_t)r);
1133 
1134 	if(ldns_buffer_remaining(c->buffer) == 0) {
1135 		tcp_callback_writer(c);
1136 	}
1137 	return 1;
1138 #else
1139 	(void)c;
1140 	return 0;
1141 #endif /* HAVE_SSL */
1142 }
1143 
1144 /** handle ssl tcp connection with dns contents */
1145 static int
1146 ssl_handle_it(struct comm_point* c)
1147 {
1148 	if(c->tcp_is_reading)
1149 		return ssl_handle_read(c);
1150 	return ssl_handle_write(c);
1151 }
1152 
1153 /** Handle tcp reading callback.
1154  * @param fd: file descriptor of socket.
1155  * @param c: comm point to read from into buffer.
1156  * @param short_ok: if true, very short packets are OK (for comm_local).
1157  * @return: 0 on error
1158  */
1159 static int
1160 comm_point_tcp_handle_read(int fd, struct comm_point* c, int short_ok)
1161 {
1162 	ssize_t r;
1163 	log_assert(c->type == comm_tcp || c->type == comm_local);
1164 	if(c->ssl)
1165 		return ssl_handle_it(c);
1166 	if(!c->tcp_is_reading)
1167 		return 0;
1168 
1169 	log_assert(fd != -1);
1170 	if(c->tcp_byte_count < sizeof(uint16_t)) {
1171 		/* read length bytes */
1172 		r = recv(fd,(void*)ldns_buffer_at(c->buffer,c->tcp_byte_count),
1173 			sizeof(uint16_t)-c->tcp_byte_count, 0);
1174 		if(r == 0)
1175 			return 0;
1176 		else if(r == -1) {
1177 #ifndef USE_WINSOCK
1178 			if(errno == EINTR || errno == EAGAIN)
1179 				return 1;
1180 #ifdef ECONNRESET
1181 			if(errno == ECONNRESET && verbosity < 2)
1182 				return 0; /* silence reset by peer */
1183 #endif
1184 			log_err("read (in tcp s): %s", strerror(errno));
1185 #else /* USE_WINSOCK */
1186 			if(WSAGetLastError() == WSAECONNRESET)
1187 				return 0;
1188 			if(WSAGetLastError() == WSAEINPROGRESS)
1189 				return 1;
1190 			if(WSAGetLastError() == WSAEWOULDBLOCK) {
1191 				winsock_tcp_wouldblock(&c->ev->ev, EV_READ);
1192 				return 1;
1193 			}
1194 			log_err("read (in tcp s): %s",
1195 				wsa_strerror(WSAGetLastError()));
1196 #endif
1197 			log_addr(0, "remote address is", &c->repinfo.addr,
1198 				c->repinfo.addrlen);
1199 			return 0;
1200 		}
1201 		c->tcp_byte_count += r;
1202 		if(c->tcp_byte_count != sizeof(uint16_t))
1203 			return 1;
1204 		if(ldns_buffer_read_u16_at(c->buffer, 0) >
1205 			ldns_buffer_capacity(c->buffer)) {
1206 			verbose(VERB_QUERY, "tcp: dropped larger than buffer");
1207 			return 0;
1208 		}
1209 		ldns_buffer_set_limit(c->buffer,
1210 			ldns_buffer_read_u16_at(c->buffer, 0));
1211 		if(!short_ok &&
1212 			ldns_buffer_limit(c->buffer) < LDNS_HEADER_SIZE) {
1213 			verbose(VERB_QUERY, "tcp: dropped bogus too short.");
1214 			return 0;
1215 		}
1216 		verbose(VERB_ALGO, "Reading tcp query of length %d",
1217 			(int)ldns_buffer_limit(c->buffer));
1218 	}
1219 
1220 	log_assert(ldns_buffer_remaining(c->buffer) > 0);
1221 	r = recv(fd, (void*)ldns_buffer_current(c->buffer),
1222 		ldns_buffer_remaining(c->buffer), 0);
1223 	if(r == 0) {
1224 		return 0;
1225 	} else if(r == -1) {
1226 #ifndef USE_WINSOCK
1227 		if(errno == EINTR || errno == EAGAIN)
1228 			return 1;
1229 		log_err("read (in tcp r): %s", strerror(errno));
1230 #else /* USE_WINSOCK */
1231 		if(WSAGetLastError() == WSAECONNRESET)
1232 			return 0;
1233 		if(WSAGetLastError() == WSAEINPROGRESS)
1234 			return 1;
1235 		if(WSAGetLastError() == WSAEWOULDBLOCK) {
1236 			winsock_tcp_wouldblock(&c->ev->ev, EV_READ);
1237 			return 1;
1238 		}
1239 		log_err("read (in tcp r): %s",
1240 			wsa_strerror(WSAGetLastError()));
1241 #endif
1242 		log_addr(0, "remote address is", &c->repinfo.addr,
1243 			c->repinfo.addrlen);
1244 		return 0;
1245 	}
1246 	ldns_buffer_skip(c->buffer, r);
1247 	if(ldns_buffer_remaining(c->buffer) <= 0) {
1248 		tcp_callback_reader(c);
1249 	}
1250 	return 1;
1251 }
1252 
1253 /**
1254  * Handle tcp writing callback.
1255  * @param fd: file descriptor of socket.
1256  * @param c: comm point to write buffer out of.
1257  * @return: 0 on error
1258  */
1259 static int
1260 comm_point_tcp_handle_write(int fd, struct comm_point* c)
1261 {
1262 	ssize_t r;
1263 	log_assert(c->type == comm_tcp);
1264 	if(c->tcp_is_reading && !c->ssl)
1265 		return 0;
1266 	log_assert(fd != -1);
1267 	if(c->tcp_byte_count == 0 && c->tcp_check_nb_connect) {
1268 		/* check for pending error from nonblocking connect */
1269 		/* from Stevens, unix network programming, vol1, 3rd ed, p450*/
1270 		int error = 0;
1271 		socklen_t len = (socklen_t)sizeof(error);
1272 		if(getsockopt(fd, SOL_SOCKET, SO_ERROR, (void*)&error,
1273 			&len) < 0){
1274 #ifndef USE_WINSOCK
1275 			error = errno; /* on solaris errno is error */
1276 #else /* USE_WINSOCK */
1277 			error = WSAGetLastError();
1278 #endif
1279 		}
1280 #ifndef USE_WINSOCK
1281 #if defined(EINPROGRESS) && defined(EWOULDBLOCK)
1282 		if(error == EINPROGRESS || error == EWOULDBLOCK)
1283 			return 1; /* try again later */
1284 		else
1285 #endif
1286 		if(error != 0 && verbosity < 2)
1287 			return 0; /* silence lots of chatter in the logs */
1288                 else if(error != 0) {
1289 			log_err("tcp connect: %s", strerror(error));
1290 #else /* USE_WINSOCK */
1291 		/* examine error */
1292 		if(error == WSAEINPROGRESS)
1293 			return 1;
1294 		else if(error == WSAEWOULDBLOCK) {
1295 			winsock_tcp_wouldblock(&c->ev->ev, EV_WRITE);
1296 			return 1;
1297 		} else if(error != 0 && verbosity < 2)
1298 			return 0;
1299 		else if(error != 0) {
1300 			log_err("tcp connect: %s", wsa_strerror(error));
1301 #endif /* USE_WINSOCK */
1302 			log_addr(0, "remote address is", &c->repinfo.addr,
1303 				c->repinfo.addrlen);
1304 			return 0;
1305 		}
1306 	}
1307 	if(c->ssl)
1308 		return ssl_handle_it(c);
1309 
1310 	if(c->tcp_byte_count < sizeof(uint16_t)) {
1311 		uint16_t len = htons(ldns_buffer_limit(c->buffer));
1312 #ifdef HAVE_WRITEV
1313 		struct iovec iov[2];
1314 		iov[0].iov_base = (uint8_t*)&len + c->tcp_byte_count;
1315 		iov[0].iov_len = sizeof(uint16_t) - c->tcp_byte_count;
1316 		iov[1].iov_base = ldns_buffer_begin(c->buffer);
1317 		iov[1].iov_len = ldns_buffer_limit(c->buffer);
1318 		log_assert(iov[0].iov_len > 0);
1319 		log_assert(iov[1].iov_len > 0);
1320 		r = writev(fd, iov, 2);
1321 #else /* HAVE_WRITEV */
1322 		r = send(fd, (void*)(((uint8_t*)&len)+c->tcp_byte_count),
1323 			sizeof(uint16_t)-c->tcp_byte_count, 0);
1324 #endif /* HAVE_WRITEV */
1325 		if(r == -1) {
1326 #ifndef USE_WINSOCK
1327 #ifdef EPIPE
1328                 	if(errno == EPIPE && verbosity < 2)
1329                         	return 0; /* silence 'broken pipe' */
1330 #endif
1331 			if(errno == EINTR || errno == EAGAIN)
1332 				return 1;
1333 			log_err("tcp writev: %s", strerror(errno));
1334 #else
1335 			if(WSAGetLastError() == WSAENOTCONN)
1336 				return 1;
1337 			if(WSAGetLastError() == WSAEINPROGRESS)
1338 				return 1;
1339 			if(WSAGetLastError() == WSAEWOULDBLOCK) {
1340 				winsock_tcp_wouldblock(&c->ev->ev, EV_WRITE);
1341 				return 1;
1342 			}
1343 			log_err("tcp send s: %s",
1344 				wsa_strerror(WSAGetLastError()));
1345 #endif
1346 			log_addr(0, "remote address is", &c->repinfo.addr,
1347 				c->repinfo.addrlen);
1348 			return 0;
1349 		}
1350 		c->tcp_byte_count += r;
1351 		if(c->tcp_byte_count < sizeof(uint16_t))
1352 			return 1;
1353 		ldns_buffer_set_position(c->buffer, c->tcp_byte_count -
1354 			sizeof(uint16_t));
1355 		if(ldns_buffer_remaining(c->buffer) == 0) {
1356 			tcp_callback_writer(c);
1357 			return 1;
1358 		}
1359 	}
1360 	log_assert(ldns_buffer_remaining(c->buffer) > 0);
1361 	r = send(fd, (void*)ldns_buffer_current(c->buffer),
1362 		ldns_buffer_remaining(c->buffer), 0);
1363 	if(r == -1) {
1364 #ifndef USE_WINSOCK
1365 		if(errno == EINTR || errno == EAGAIN)
1366 			return 1;
1367 		log_err("tcp send r: %s", strerror(errno));
1368 #else
1369 		if(WSAGetLastError() == WSAEINPROGRESS)
1370 			return 1;
1371 		if(WSAGetLastError() == WSAEWOULDBLOCK) {
1372 			winsock_tcp_wouldblock(&c->ev->ev, EV_WRITE);
1373 			return 1;
1374 		}
1375 		log_err("tcp send r: %s",
1376 			wsa_strerror(WSAGetLastError()));
1377 #endif
1378 		log_addr(0, "remote address is", &c->repinfo.addr,
1379 			c->repinfo.addrlen);
1380 		return 0;
1381 	}
1382 	ldns_buffer_skip(c->buffer, r);
1383 
1384 	if(ldns_buffer_remaining(c->buffer) == 0) {
1385 		tcp_callback_writer(c);
1386 	}
1387 
1388 	return 1;
1389 }
1390 
1391 void
1392 comm_point_tcp_handle_callback(int fd, short event, void* arg)
1393 {
1394 	struct comm_point* c = (struct comm_point*)arg;
1395 	log_assert(c->type == comm_tcp);
1396 	comm_base_now(c->ev->base);
1397 
1398 	if(event&EV_READ) {
1399 		if(!comm_point_tcp_handle_read(fd, c, 0)) {
1400 			reclaim_tcp_handler(c);
1401 			if(!c->tcp_do_close) {
1402 				fptr_ok(fptr_whitelist_comm_point(
1403 					c->callback));
1404 				(void)(*c->callback)(c, c->cb_arg,
1405 					NETEVENT_CLOSED, NULL);
1406 			}
1407 		}
1408 		return;
1409 	}
1410 	if(event&EV_WRITE) {
1411 		if(!comm_point_tcp_handle_write(fd, c)) {
1412 			reclaim_tcp_handler(c);
1413 			if(!c->tcp_do_close) {
1414 				fptr_ok(fptr_whitelist_comm_point(
1415 					c->callback));
1416 				(void)(*c->callback)(c, c->cb_arg,
1417 					NETEVENT_CLOSED, NULL);
1418 			}
1419 		}
1420 		return;
1421 	}
1422 	if(event&EV_TIMEOUT) {
1423 		verbose(VERB_QUERY, "tcp took too long, dropped");
1424 		reclaim_tcp_handler(c);
1425 		if(!c->tcp_do_close) {
1426 			fptr_ok(fptr_whitelist_comm_point(c->callback));
1427 			(void)(*c->callback)(c, c->cb_arg,
1428 				NETEVENT_TIMEOUT, NULL);
1429 		}
1430 		return;
1431 	}
1432 	log_err("Ignored event %d for tcphdl.", event);
1433 }
1434 
1435 void comm_point_local_handle_callback(int fd, short event, void* arg)
1436 {
1437 	struct comm_point* c = (struct comm_point*)arg;
1438 	log_assert(c->type == comm_local);
1439 	comm_base_now(c->ev->base);
1440 
1441 	if(event&EV_READ) {
1442 		if(!comm_point_tcp_handle_read(fd, c, 1)) {
1443 			fptr_ok(fptr_whitelist_comm_point(c->callback));
1444 			(void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED,
1445 				NULL);
1446 		}
1447 		return;
1448 	}
1449 	log_err("Ignored event %d for localhdl.", event);
1450 }
1451 
1452 void comm_point_raw_handle_callback(int ATTR_UNUSED(fd),
1453 	short event, void* arg)
1454 {
1455 	struct comm_point* c = (struct comm_point*)arg;
1456 	int err = NETEVENT_NOERROR;
1457 	log_assert(c->type == comm_raw);
1458 	comm_base_now(c->ev->base);
1459 
1460 	if(event&EV_TIMEOUT)
1461 		err = NETEVENT_TIMEOUT;
1462 	fptr_ok(fptr_whitelist_comm_point_raw(c->callback));
1463 	(void)(*c->callback)(c, c->cb_arg, err, NULL);
1464 }
1465 
1466 struct comm_point*
1467 comm_point_create_udp(struct comm_base *base, int fd, ldns_buffer* buffer,
1468 	comm_point_callback_t* callback, void* callback_arg)
1469 {
1470 	struct comm_point* c = (struct comm_point*)calloc(1,
1471 		sizeof(struct comm_point));
1472 	short evbits;
1473 	if(!c)
1474 		return NULL;
1475 	c->ev = (struct internal_event*)calloc(1,
1476 		sizeof(struct internal_event));
1477 	if(!c->ev) {
1478 		free(c);
1479 		return NULL;
1480 	}
1481 	c->ev->base = base;
1482 	c->fd = fd;
1483 	c->buffer = buffer;
1484 	c->timeout = NULL;
1485 	c->tcp_is_reading = 0;
1486 	c->tcp_byte_count = 0;
1487 	c->tcp_parent = NULL;
1488 	c->max_tcp_count = 0;
1489 	c->tcp_handlers = NULL;
1490 	c->tcp_free = NULL;
1491 	c->type = comm_udp;
1492 	c->tcp_do_close = 0;
1493 	c->do_not_close = 0;
1494 	c->tcp_do_toggle_rw = 0;
1495 	c->tcp_check_nb_connect = 0;
1496 	c->inuse = 0;
1497 	c->callback = callback;
1498 	c->cb_arg = callback_arg;
1499 	evbits = EV_READ | EV_PERSIST;
1500 	/* libevent stuff */
1501 	event_set(&c->ev->ev, c->fd, evbits, comm_point_udp_callback, c);
1502 	if(event_base_set(base->eb->base, &c->ev->ev) != 0) {
1503 		log_err("could not baseset udp event");
1504 		comm_point_delete(c);
1505 		return NULL;
1506 	}
1507 	if(fd!=-1 && event_add(&c->ev->ev, c->timeout) != 0 ) {
1508 		log_err("could not add udp event");
1509 		comm_point_delete(c);
1510 		return NULL;
1511 	}
1512 	return c;
1513 }
1514 
1515 struct comm_point*
1516 comm_point_create_udp_ancil(struct comm_base *base, int fd,
1517 	ldns_buffer* buffer,
1518 	comm_point_callback_t* callback, void* callback_arg)
1519 {
1520 	struct comm_point* c = (struct comm_point*)calloc(1,
1521 		sizeof(struct comm_point));
1522 	short evbits;
1523 	if(!c)
1524 		return NULL;
1525 	c->ev = (struct internal_event*)calloc(1,
1526 		sizeof(struct internal_event));
1527 	if(!c->ev) {
1528 		free(c);
1529 		return NULL;
1530 	}
1531 	c->ev->base = base;
1532 	c->fd = fd;
1533 	c->buffer = buffer;
1534 	c->timeout = NULL;
1535 	c->tcp_is_reading = 0;
1536 	c->tcp_byte_count = 0;
1537 	c->tcp_parent = NULL;
1538 	c->max_tcp_count = 0;
1539 	c->tcp_handlers = NULL;
1540 	c->tcp_free = NULL;
1541 	c->type = comm_udp;
1542 	c->tcp_do_close = 0;
1543 	c->do_not_close = 0;
1544 	c->inuse = 0;
1545 	c->tcp_do_toggle_rw = 0;
1546 	c->tcp_check_nb_connect = 0;
1547 	c->callback = callback;
1548 	c->cb_arg = callback_arg;
1549 	evbits = EV_READ | EV_PERSIST;
1550 	/* libevent stuff */
1551 	event_set(&c->ev->ev, c->fd, evbits, comm_point_udp_ancil_callback, c);
1552 	if(event_base_set(base->eb->base, &c->ev->ev) != 0) {
1553 		log_err("could not baseset udp event");
1554 		comm_point_delete(c);
1555 		return NULL;
1556 	}
1557 	if(fd!=-1 && event_add(&c->ev->ev, c->timeout) != 0 ) {
1558 		log_err("could not add udp event");
1559 		comm_point_delete(c);
1560 		return NULL;
1561 	}
1562 	return c;
1563 }
1564 
1565 static struct comm_point*
1566 comm_point_create_tcp_handler(struct comm_base *base,
1567 	struct comm_point* parent, size_t bufsize,
1568         comm_point_callback_t* callback, void* callback_arg)
1569 {
1570 	struct comm_point* c = (struct comm_point*)calloc(1,
1571 		sizeof(struct comm_point));
1572 	short evbits;
1573 	if(!c)
1574 		return NULL;
1575 	c->ev = (struct internal_event*)calloc(1,
1576 		sizeof(struct internal_event));
1577 	if(!c->ev) {
1578 		free(c);
1579 		return NULL;
1580 	}
1581 	c->ev->base = base;
1582 	c->fd = -1;
1583 	c->buffer = ldns_buffer_new(bufsize);
1584 	if(!c->buffer) {
1585 		free(c->ev);
1586 		free(c);
1587 		return NULL;
1588 	}
1589 	c->timeout = (struct timeval*)malloc(sizeof(struct timeval));
1590 	if(!c->timeout) {
1591 		ldns_buffer_free(c->buffer);
1592 		free(c->ev);
1593 		free(c);
1594 		return NULL;
1595 	}
1596 	c->tcp_is_reading = 0;
1597 	c->tcp_byte_count = 0;
1598 	c->tcp_parent = parent;
1599 	c->max_tcp_count = 0;
1600 	c->tcp_handlers = NULL;
1601 	c->tcp_free = NULL;
1602 	c->type = comm_tcp;
1603 	c->tcp_do_close = 0;
1604 	c->do_not_close = 0;
1605 	c->tcp_do_toggle_rw = 1;
1606 	c->tcp_check_nb_connect = 0;
1607 	c->repinfo.c = c;
1608 	c->callback = callback;
1609 	c->cb_arg = callback_arg;
1610 	/* add to parent free list */
1611 	c->tcp_free = parent->tcp_free;
1612 	parent->tcp_free = c;
1613 	/* libevent stuff */
1614 	evbits = EV_PERSIST | EV_READ | EV_TIMEOUT;
1615 	event_set(&c->ev->ev, c->fd, evbits, comm_point_tcp_handle_callback, c);
1616 	if(event_base_set(base->eb->base, &c->ev->ev) != 0)
1617 	{
1618 		log_err("could not basetset tcphdl event");
1619 		parent->tcp_free = c->tcp_free;
1620 		free(c->ev);
1621 		free(c);
1622 		return NULL;
1623 	}
1624 	return c;
1625 }
1626 
1627 struct comm_point*
1628 comm_point_create_tcp(struct comm_base *base, int fd, int num, size_t bufsize,
1629         comm_point_callback_t* callback, void* callback_arg)
1630 {
1631 	struct comm_point* c = (struct comm_point*)calloc(1,
1632 		sizeof(struct comm_point));
1633 	short evbits;
1634 	int i;
1635 	/* first allocate the TCP accept listener */
1636 	if(!c)
1637 		return NULL;
1638 	c->ev = (struct internal_event*)calloc(1,
1639 		sizeof(struct internal_event));
1640 	if(!c->ev) {
1641 		free(c);
1642 		return NULL;
1643 	}
1644 	c->ev->base = base;
1645 	c->fd = fd;
1646 	c->buffer = NULL;
1647 	c->timeout = NULL;
1648 	c->tcp_is_reading = 0;
1649 	c->tcp_byte_count = 0;
1650 	c->tcp_parent = NULL;
1651 	c->max_tcp_count = num;
1652 	c->tcp_handlers = (struct comm_point**)calloc((size_t)num,
1653 		sizeof(struct comm_point*));
1654 	if(!c->tcp_handlers) {
1655 		free(c->ev);
1656 		free(c);
1657 		return NULL;
1658 	}
1659 	c->tcp_free = NULL;
1660 	c->type = comm_tcp_accept;
1661 	c->tcp_do_close = 0;
1662 	c->do_not_close = 0;
1663 	c->tcp_do_toggle_rw = 0;
1664 	c->tcp_check_nb_connect = 0;
1665 	c->callback = NULL;
1666 	c->cb_arg = NULL;
1667 	evbits = EV_READ | EV_PERSIST;
1668 	/* libevent stuff */
1669 	event_set(&c->ev->ev, c->fd, evbits, comm_point_tcp_accept_callback, c);
1670 	if(event_base_set(base->eb->base, &c->ev->ev) != 0 ||
1671 		event_add(&c->ev->ev, c->timeout) != 0 )
1672 	{
1673 		log_err("could not add tcpacc event");
1674 		comm_point_delete(c);
1675 		return NULL;
1676 	}
1677 
1678 	/* now prealloc the tcp handlers */
1679 	for(i=0; i<num; i++) {
1680 		c->tcp_handlers[i] = comm_point_create_tcp_handler(base,
1681 			c, bufsize, callback, callback_arg);
1682 		if(!c->tcp_handlers[i]) {
1683 			comm_point_delete(c);
1684 			return NULL;
1685 		}
1686 	}
1687 
1688 	return c;
1689 }
1690 
1691 struct comm_point*
1692 comm_point_create_tcp_out(struct comm_base *base, size_t bufsize,
1693         comm_point_callback_t* callback, void* callback_arg)
1694 {
1695 	struct comm_point* c = (struct comm_point*)calloc(1,
1696 		sizeof(struct comm_point));
1697 	short evbits;
1698 	if(!c)
1699 		return NULL;
1700 	c->ev = (struct internal_event*)calloc(1,
1701 		sizeof(struct internal_event));
1702 	if(!c->ev) {
1703 		free(c);
1704 		return NULL;
1705 	}
1706 	c->ev->base = base;
1707 	c->fd = -1;
1708 	c->buffer = ldns_buffer_new(bufsize);
1709 	if(!c->buffer) {
1710 		free(c->ev);
1711 		free(c);
1712 		return NULL;
1713 	}
1714 	c->timeout = NULL;
1715 	c->tcp_is_reading = 0;
1716 	c->tcp_byte_count = 0;
1717 	c->tcp_parent = NULL;
1718 	c->max_tcp_count = 0;
1719 	c->tcp_handlers = NULL;
1720 	c->tcp_free = NULL;
1721 	c->type = comm_tcp;
1722 	c->tcp_do_close = 0;
1723 	c->do_not_close = 0;
1724 	c->tcp_do_toggle_rw = 1;
1725 	c->tcp_check_nb_connect = 1;
1726 	c->repinfo.c = c;
1727 	c->callback = callback;
1728 	c->cb_arg = callback_arg;
1729 	evbits = EV_PERSIST | EV_WRITE;
1730 	event_set(&c->ev->ev, c->fd, evbits, comm_point_tcp_handle_callback, c);
1731 	if(event_base_set(base->eb->base, &c->ev->ev) != 0)
1732 	{
1733 		log_err("could not basetset tcpout event");
1734 		ldns_buffer_free(c->buffer);
1735 		free(c->ev);
1736 		free(c);
1737 		return NULL;
1738 	}
1739 
1740 	return c;
1741 }
1742 
1743 struct comm_point*
1744 comm_point_create_local(struct comm_base *base, int fd, size_t bufsize,
1745         comm_point_callback_t* callback, void* callback_arg)
1746 {
1747 	struct comm_point* c = (struct comm_point*)calloc(1,
1748 		sizeof(struct comm_point));
1749 	short evbits;
1750 	if(!c)
1751 		return NULL;
1752 	c->ev = (struct internal_event*)calloc(1,
1753 		sizeof(struct internal_event));
1754 	if(!c->ev) {
1755 		free(c);
1756 		return NULL;
1757 	}
1758 	c->ev->base = base;
1759 	c->fd = fd;
1760 	c->buffer = ldns_buffer_new(bufsize);
1761 	if(!c->buffer) {
1762 		free(c->ev);
1763 		free(c);
1764 		return NULL;
1765 	}
1766 	c->timeout = NULL;
1767 	c->tcp_is_reading = 1;
1768 	c->tcp_byte_count = 0;
1769 	c->tcp_parent = NULL;
1770 	c->max_tcp_count = 0;
1771 	c->tcp_handlers = NULL;
1772 	c->tcp_free = NULL;
1773 	c->type = comm_local;
1774 	c->tcp_do_close = 0;
1775 	c->do_not_close = 1;
1776 	c->tcp_do_toggle_rw = 0;
1777 	c->tcp_check_nb_connect = 0;
1778 	c->callback = callback;
1779 	c->cb_arg = callback_arg;
1780 	/* libevent stuff */
1781 	evbits = EV_PERSIST | EV_READ;
1782 	event_set(&c->ev->ev, c->fd, evbits, comm_point_local_handle_callback,
1783 		c);
1784 	if(event_base_set(base->eb->base, &c->ev->ev) != 0 ||
1785 		event_add(&c->ev->ev, c->timeout) != 0 )
1786 	{
1787 		log_err("could not add localhdl event");
1788 		free(c->ev);
1789 		free(c);
1790 		return NULL;
1791 	}
1792 	return c;
1793 }
1794 
1795 struct comm_point*
1796 comm_point_create_raw(struct comm_base* base, int fd, int writing,
1797 	comm_point_callback_t* callback, void* callback_arg)
1798 {
1799 	struct comm_point* c = (struct comm_point*)calloc(1,
1800 		sizeof(struct comm_point));
1801 	short evbits;
1802 	if(!c)
1803 		return NULL;
1804 	c->ev = (struct internal_event*)calloc(1,
1805 		sizeof(struct internal_event));
1806 	if(!c->ev) {
1807 		free(c);
1808 		return NULL;
1809 	}
1810 	c->ev->base = base;
1811 	c->fd = fd;
1812 	c->buffer = NULL;
1813 	c->timeout = NULL;
1814 	c->tcp_is_reading = 0;
1815 	c->tcp_byte_count = 0;
1816 	c->tcp_parent = NULL;
1817 	c->max_tcp_count = 0;
1818 	c->tcp_handlers = NULL;
1819 	c->tcp_free = NULL;
1820 	c->type = comm_raw;
1821 	c->tcp_do_close = 0;
1822 	c->do_not_close = 1;
1823 	c->tcp_do_toggle_rw = 0;
1824 	c->tcp_check_nb_connect = 0;
1825 	c->callback = callback;
1826 	c->cb_arg = callback_arg;
1827 	/* libevent stuff */
1828 	if(writing)
1829 		evbits = EV_PERSIST | EV_WRITE;
1830 	else 	evbits = EV_PERSIST | EV_READ;
1831 	event_set(&c->ev->ev, c->fd, evbits, comm_point_raw_handle_callback,
1832 		c);
1833 	if(event_base_set(base->eb->base, &c->ev->ev) != 0 ||
1834 		event_add(&c->ev->ev, c->timeout) != 0 )
1835 	{
1836 		log_err("could not add rawhdl event");
1837 		free(c->ev);
1838 		free(c);
1839 		return NULL;
1840 	}
1841 	return c;
1842 }
1843 
1844 void
1845 comm_point_close(struct comm_point* c)
1846 {
1847 	if(!c)
1848 		return;
1849 	if(c->fd != -1)
1850 		if(event_del(&c->ev->ev) != 0) {
1851 			log_err("could not event_del on close");
1852 		}
1853 	/* close fd after removing from event lists, or epoll.. is messed up */
1854 	if(c->fd != -1 && !c->do_not_close) {
1855 		verbose(VERB_ALGO, "close fd %d", c->fd);
1856 #ifndef USE_WINSOCK
1857 		close(c->fd);
1858 #else
1859 		closesocket(c->fd);
1860 #endif
1861 	}
1862 	c->fd = -1;
1863 }
1864 
1865 void
1866 comm_point_delete(struct comm_point* c)
1867 {
1868 	if(!c)
1869 		return;
1870 	if(c->type == comm_tcp && c->ssl) {
1871 #ifdef HAVE_SSL
1872 		SSL_shutdown(c->ssl);
1873 		SSL_free(c->ssl);
1874 #endif
1875 	}
1876 	comm_point_close(c);
1877 	if(c->tcp_handlers) {
1878 		int i;
1879 		for(i=0; i<c->max_tcp_count; i++)
1880 			comm_point_delete(c->tcp_handlers[i]);
1881 		free(c->tcp_handlers);
1882 	}
1883 	free(c->timeout);
1884 	if(c->type == comm_tcp || c->type == comm_local)
1885 		ldns_buffer_free(c->buffer);
1886 	free(c->ev);
1887 	free(c);
1888 }
1889 
1890 void
1891 comm_point_send_reply(struct comm_reply *repinfo)
1892 {
1893 	log_assert(repinfo && repinfo->c);
1894 	if(repinfo->c->type == comm_udp) {
1895 		if(repinfo->srctype)
1896 			comm_point_send_udp_msg_if(repinfo->c,
1897 			repinfo->c->buffer, (struct sockaddr*)&repinfo->addr,
1898 			repinfo->addrlen, repinfo);
1899 		else
1900 			comm_point_send_udp_msg(repinfo->c, repinfo->c->buffer,
1901 			(struct sockaddr*)&repinfo->addr, repinfo->addrlen);
1902 	} else {
1903 		comm_point_start_listening(repinfo->c, -1, TCP_QUERY_TIMEOUT);
1904 	}
1905 }
1906 
1907 void
1908 comm_point_drop_reply(struct comm_reply* repinfo)
1909 {
1910 	if(!repinfo)
1911 		return;
1912 	log_assert(repinfo && repinfo->c);
1913 	log_assert(repinfo->c->type != comm_tcp_accept);
1914 	if(repinfo->c->type == comm_udp)
1915 		return;
1916 	reclaim_tcp_handler(repinfo->c);
1917 }
1918 
1919 void
1920 comm_point_stop_listening(struct comm_point* c)
1921 {
1922 	verbose(VERB_ALGO, "comm point stop listening %d", c->fd);
1923 	if(event_del(&c->ev->ev) != 0) {
1924 		log_err("event_del error to stoplisten");
1925 	}
1926 }
1927 
1928 void
1929 comm_point_start_listening(struct comm_point* c, int newfd, int sec)
1930 {
1931 	verbose(VERB_ALGO, "comm point start listening %d",
1932 		c->fd==-1?newfd:c->fd);
1933 	if(c->type == comm_tcp_accept && !c->tcp_free) {
1934 		/* no use to start listening no free slots. */
1935 		return;
1936 	}
1937 	if(sec != -1 && sec != 0) {
1938 		if(!c->timeout) {
1939 			c->timeout = (struct timeval*)malloc(sizeof(
1940 				struct timeval));
1941 			if(!c->timeout) {
1942 				log_err("cpsl: malloc failed. No net read.");
1943 				return;
1944 			}
1945 		}
1946 		c->ev->ev.ev_events |= EV_TIMEOUT;
1947 #ifndef S_SPLINT_S /* splint fails on struct timeval. */
1948 		c->timeout->tv_sec = sec;
1949 		c->timeout->tv_usec = 0;
1950 #endif /* S_SPLINT_S */
1951 	}
1952 	if(c->type == comm_tcp) {
1953 		c->ev->ev.ev_events &= ~(EV_READ|EV_WRITE);
1954 		if(c->tcp_is_reading)
1955 			c->ev->ev.ev_events |= EV_READ;
1956 		else	c->ev->ev.ev_events |= EV_WRITE;
1957 	}
1958 	if(newfd != -1) {
1959 		if(c->fd != -1) {
1960 #ifndef USE_WINSOCK
1961 			close(c->fd);
1962 #else
1963 			closesocket(c->fd);
1964 #endif
1965 		}
1966 		c->fd = newfd;
1967 		c->ev->ev.ev_fd = c->fd;
1968 	}
1969 	if(event_add(&c->ev->ev, sec==0?NULL:c->timeout) != 0) {
1970 		log_err("event_add failed. in cpsl.");
1971 	}
1972 }
1973 
1974 void comm_point_listen_for_rw(struct comm_point* c, int rd, int wr)
1975 {
1976 	verbose(VERB_ALGO, "comm point listen_for_rw %d %d", c->fd, wr);
1977 	if(event_del(&c->ev->ev) != 0) {
1978 		log_err("event_del error to cplf");
1979 	}
1980 	c->ev->ev.ev_events &= ~(EV_READ|EV_WRITE);
1981 	if(rd) c->ev->ev.ev_events |= EV_READ;
1982 	if(wr) c->ev->ev.ev_events |= EV_WRITE;
1983 	if(event_add(&c->ev->ev, c->timeout) != 0) {
1984 		log_err("event_add failed. in cplf.");
1985 	}
1986 }
1987 
1988 size_t comm_point_get_mem(struct comm_point* c)
1989 {
1990 	size_t s;
1991 	if(!c)
1992 		return 0;
1993 	s = sizeof(*c) + sizeof(*c->ev);
1994 	if(c->timeout)
1995 		s += sizeof(*c->timeout);
1996 	if(c->type == comm_tcp || c->type == comm_local)
1997 		s += sizeof(*c->buffer) + ldns_buffer_capacity(c->buffer);
1998 	if(c->type == comm_tcp_accept) {
1999 		int i;
2000 		for(i=0; i<c->max_tcp_count; i++)
2001 			s += comm_point_get_mem(c->tcp_handlers[i]);
2002 	}
2003 	return s;
2004 }
2005 
2006 struct comm_timer*
2007 comm_timer_create(struct comm_base* base, void (*cb)(void*), void* cb_arg)
2008 {
2009 	struct comm_timer *tm = (struct comm_timer*)calloc(1,
2010 		sizeof(struct comm_timer));
2011 	if(!tm)
2012 		return NULL;
2013 	tm->ev_timer = (struct internal_timer*)calloc(1,
2014 		sizeof(struct internal_timer));
2015 	if(!tm->ev_timer) {
2016 		log_err("malloc failed");
2017 		free(tm);
2018 		return NULL;
2019 	}
2020 	tm->ev_timer->base = base;
2021 	tm->callback = cb;
2022 	tm->cb_arg = cb_arg;
2023 	event_set(&tm->ev_timer->ev, -1, EV_TIMEOUT,
2024 		comm_timer_callback, tm);
2025 	if(event_base_set(base->eb->base, &tm->ev_timer->ev) != 0) {
2026 		log_err("timer_create: event_base_set failed.");
2027 		free(tm->ev_timer);
2028 		free(tm);
2029 		return NULL;
2030 	}
2031 	return tm;
2032 }
2033 
2034 void
2035 comm_timer_disable(struct comm_timer* timer)
2036 {
2037 	if(!timer)
2038 		return;
2039 	evtimer_del(&timer->ev_timer->ev);
2040 	timer->ev_timer->enabled = 0;
2041 }
2042 
2043 void
2044 comm_timer_set(struct comm_timer* timer, struct timeval* tv)
2045 {
2046 	log_assert(tv);
2047 	if(timer->ev_timer->enabled)
2048 		comm_timer_disable(timer);
2049 	event_set(&timer->ev_timer->ev, -1, EV_TIMEOUT,
2050 		comm_timer_callback, timer);
2051 	if(event_base_set(timer->ev_timer->base->eb->base,
2052 		&timer->ev_timer->ev) != 0)
2053 		log_err("comm_timer_set: set_base failed.");
2054 	if(evtimer_add(&timer->ev_timer->ev, tv) != 0)
2055 		log_err("comm_timer_set: evtimer_add failed.");
2056 	timer->ev_timer->enabled = 1;
2057 }
2058 
2059 void
2060 comm_timer_delete(struct comm_timer* timer)
2061 {
2062 	if(!timer)
2063 		return;
2064 	comm_timer_disable(timer);
2065 	free(timer->ev_timer);
2066 	free(timer);
2067 }
2068 
2069 void
2070 comm_timer_callback(int ATTR_UNUSED(fd), short event, void* arg)
2071 {
2072 	struct comm_timer* tm = (struct comm_timer*)arg;
2073 	if(!(event&EV_TIMEOUT))
2074 		return;
2075 	comm_base_now(tm->ev_timer->base);
2076 	tm->ev_timer->enabled = 0;
2077 	fptr_ok(fptr_whitelist_comm_timer(tm->callback));
2078 	(*tm->callback)(tm->cb_arg);
2079 }
2080 
2081 int
2082 comm_timer_is_set(struct comm_timer* timer)
2083 {
2084 	return (int)timer->ev_timer->enabled;
2085 }
2086 
2087 size_t
2088 comm_timer_get_mem(struct comm_timer* timer)
2089 {
2090 	return sizeof(*timer) + sizeof(struct internal_timer);
2091 }
2092 
2093 struct comm_signal*
2094 comm_signal_create(struct comm_base* base,
2095         void (*callback)(int, void*), void* cb_arg)
2096 {
2097 	struct comm_signal* com = (struct comm_signal*)malloc(
2098 		sizeof(struct comm_signal));
2099 	if(!com) {
2100 		log_err("malloc failed");
2101 		return NULL;
2102 	}
2103 	com->base = base;
2104 	com->callback = callback;
2105 	com->cb_arg = cb_arg;
2106 	com->ev_signal = NULL;
2107 	return com;
2108 }
2109 
2110 void
2111 comm_signal_callback(int sig, short event, void* arg)
2112 {
2113 	struct comm_signal* comsig = (struct comm_signal*)arg;
2114 	if(!(event & EV_SIGNAL))
2115 		return;
2116 	comm_base_now(comsig->base);
2117 	fptr_ok(fptr_whitelist_comm_signal(comsig->callback));
2118 	(*comsig->callback)(sig, comsig->cb_arg);
2119 }
2120 
2121 int
2122 comm_signal_bind(struct comm_signal* comsig, int sig)
2123 {
2124 	struct internal_signal* entry = (struct internal_signal*)calloc(1,
2125 		sizeof(struct internal_signal));
2126 	if(!entry) {
2127 		log_err("malloc failed");
2128 		return 0;
2129 	}
2130 	log_assert(comsig);
2131 	/* add signal event */
2132 	signal_set(&entry->ev, sig, comm_signal_callback, comsig);
2133 	if(event_base_set(comsig->base->eb->base, &entry->ev) != 0) {
2134 		log_err("Could not set signal base");
2135 		free(entry);
2136 		return 0;
2137 	}
2138 	if(signal_add(&entry->ev, NULL) != 0) {
2139 		log_err("Could not add signal handler");
2140 		free(entry);
2141 		return 0;
2142 	}
2143 	/* link into list */
2144 	entry->next = comsig->ev_signal;
2145 	comsig->ev_signal = entry;
2146 	return 1;
2147 }
2148 
2149 void
2150 comm_signal_delete(struct comm_signal* comsig)
2151 {
2152 	struct internal_signal* p, *np;
2153 	if(!comsig)
2154 		return;
2155 	p=comsig->ev_signal;
2156 	while(p) {
2157 		np = p->next;
2158 		signal_del(&p->ev);
2159 		free(p);
2160 		p = np;
2161 	}
2162 	free(comsig);
2163 }
2164