xref: /openbsd-src/usr.sbin/bgpd/control.c (revision fc405d53b73a2d73393cb97f684863d17b583e38)
1 /*	$OpenBSD: control.c,v 1.110 2023/04/20 12:53:27 claudio Exp $ */
2 
3 /*
4  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
5  *
6  * Permission to use, copy, modify, and distribute this software for any
7  * purpose with or without fee is hereby granted, provided that the above
8  * copyright notice and this permission notice appear in all copies.
9  *
10  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17  */
18 
19 #include <sys/types.h>
20 #include <sys/stat.h>
21 #include <sys/socket.h>
22 #include <sys/un.h>
23 #include <errno.h>
24 #include <stdlib.h>
25 #include <string.h>
26 #include <unistd.h>
27 
28 #include "bgpd.h"
29 #include "session.h"
30 #include "log.h"
31 
32 TAILQ_HEAD(ctl_conns, ctl_conn) ctl_conns = TAILQ_HEAD_INITIALIZER(ctl_conns);
33 
34 #define	CONTROL_BACKLOG	5
35 
36 struct ctl_conn	*control_connbyfd(int);
37 struct ctl_conn	*control_connbypid(pid_t);
38 int		 control_close(struct ctl_conn *);
39 void		 control_result(struct ctl_conn *, u_int);
40 ssize_t		 imsg_read_nofd(struct imsgbuf *);
41 
42 int
43 control_check(char *path)
44 {
45 	struct sockaddr_un	 sa_un;
46 	int			 fd;
47 
48 	memset(&sa_un, 0, sizeof(sa_un));
49 	sa_un.sun_family = AF_UNIX;
50 	strlcpy(sa_un.sun_path, path, sizeof(sa_un.sun_path));
51 
52 	if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC, 0)) == -1) {
53 		log_warn("%s: socket", __func__);
54 		return (-1);
55 	}
56 
57 	if (connect(fd, (struct sockaddr *)&sa_un, sizeof(sa_un)) == 0) {
58 		log_warnx("control socket %s already in use", path);
59 		close(fd);
60 		return (-1);
61 	}
62 
63 	close(fd);
64 
65 	return (0);
66 }
67 
68 int
69 control_init(int restricted, char *path)
70 {
71 	struct sockaddr_un	 sa_un;
72 	int			 fd;
73 	mode_t			 old_umask, mode;
74 
75 	if ((fd = socket(AF_UNIX, SOCK_STREAM | SOCK_CLOEXEC | SOCK_NONBLOCK,
76 	    0)) == -1) {
77 		log_warn("control_init: socket");
78 		return (-1);
79 	}
80 
81 	memset(&sa_un, 0, sizeof(sa_un));
82 	sa_un.sun_family = AF_UNIX;
83 	if (strlcpy(sa_un.sun_path, path, sizeof(sa_un.sun_path)) >=
84 	    sizeof(sa_un.sun_path)) {
85 		log_warn("control_init: socket name too long");
86 		close(fd);
87 		return (-1);
88 	}
89 
90 	if (unlink(path) == -1)
91 		if (errno != ENOENT) {
92 			log_warn("control_init: unlink %s", path);
93 			close(fd);
94 			return (-1);
95 		}
96 
97 	if (restricted) {
98 		old_umask = umask(S_IXUSR|S_IXGRP|S_IXOTH);
99 		mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP|S_IROTH|S_IWOTH;
100 	} else {
101 		old_umask = umask(S_IXUSR|S_IXGRP|S_IWOTH|S_IROTH|S_IXOTH);
102 		mode = S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP;
103 	}
104 
105 	if (bind(fd, (struct sockaddr *)&sa_un, sizeof(sa_un)) == -1) {
106 		log_warn("control_init: bind: %s", path);
107 		close(fd);
108 		umask(old_umask);
109 		return (-1);
110 	}
111 
112 	umask(old_umask);
113 
114 	if (chmod(path, mode) == -1) {
115 		log_warn("control_init: chmod: %s", path);
116 		close(fd);
117 		unlink(path);
118 		return (-1);
119 	}
120 
121 	return (fd);
122 }
123 
124 int
125 control_listen(int fd)
126 {
127 	if (fd != -1 && listen(fd, CONTROL_BACKLOG) == -1) {
128 		log_warn("control_listen: listen");
129 		return (-1);
130 	}
131 
132 	return (0);
133 }
134 
135 void
136 control_shutdown(int fd)
137 {
138 	close(fd);
139 }
140 
141 size_t
142 control_fill_pfds(struct pollfd *pfd, size_t size)
143 {
144 	struct ctl_conn	*ctl_conn;
145 	size_t i = 0;
146 
147 	TAILQ_FOREACH(ctl_conn, &ctl_conns, entry) {
148 		pfd[i].fd = ctl_conn->ibuf.fd;
149 		pfd[i].events = POLLIN;
150 		if (ctl_conn->ibuf.w.queued > 0)
151 			pfd[i].events |= POLLOUT;
152 		i++;
153 	}
154 	return i;
155 }
156 
157 unsigned int
158 control_accept(int listenfd, int restricted)
159 {
160 	int			 connfd;
161 	socklen_t		 len;
162 	struct sockaddr_un	 sa_un;
163 	struct ctl_conn		*ctl_conn;
164 
165 	len = sizeof(sa_un);
166 	if ((connfd = accept4(listenfd,
167 	    (struct sockaddr *)&sa_un, &len,
168 	    SOCK_NONBLOCK | SOCK_CLOEXEC)) == -1) {
169 		if (errno == ENFILE || errno == EMFILE) {
170 			pauseaccept = getmonotime();
171 			return (0);
172 		} else if (errno != EWOULDBLOCK && errno != EINTR &&
173 		    errno != ECONNABORTED)
174 			log_warn("control_accept: accept");
175 		return (0);
176 	}
177 
178 	if ((ctl_conn = calloc(1, sizeof(struct ctl_conn))) == NULL) {
179 		log_warn("control_accept");
180 		close(connfd);
181 		return (0);
182 	}
183 
184 	imsg_init(&ctl_conn->ibuf, connfd);
185 	ctl_conn->restricted = restricted;
186 
187 	TAILQ_INSERT_TAIL(&ctl_conns, ctl_conn, entry);
188 
189 	return (1);
190 }
191 
192 struct ctl_conn *
193 control_connbyfd(int fd)
194 {
195 	struct ctl_conn	*c;
196 
197 	TAILQ_FOREACH(c, &ctl_conns, entry) {
198 		if (c->ibuf.fd == fd)
199 			break;
200 	}
201 
202 	return (c);
203 }
204 
205 struct ctl_conn *
206 control_connbypid(pid_t pid)
207 {
208 	struct ctl_conn	*c;
209 
210 	TAILQ_FOREACH(c, &ctl_conns, entry) {
211 		if (c->ibuf.pid == pid)
212 			break;
213 	}
214 
215 	return (c);
216 }
217 
218 int
219 control_close(struct ctl_conn *c)
220 {
221 	if (c->terminate && c->ibuf.pid)
222 		imsg_ctl_rde(IMSG_CTL_TERMINATE, 0, c->ibuf.pid, NULL, 0);
223 
224 	msgbuf_clear(&c->ibuf.w);
225 	TAILQ_REMOVE(&ctl_conns, c, entry);
226 
227 	close(c->ibuf.fd);
228 	free(c);
229 	pauseaccept = 0;
230 	return (1);
231 }
232 
233 int
234 control_dispatch_msg(struct pollfd *pfd, struct peer_head *peers)
235 {
236 	struct imsg		 imsg;
237 	struct ctl_conn		*c;
238 	ssize_t			 n;
239 	int			 verbose, matched;
240 	struct peer		*p;
241 	struct ctl_neighbor	*neighbor;
242 	struct ctl_show_rib_request	*ribreq;
243 
244 	if ((c = control_connbyfd(pfd->fd)) == NULL) {
245 		log_warn("control_dispatch_msg: fd %d: not found", pfd->fd);
246 		return (0);
247 	}
248 
249 	if (pfd->revents & POLLOUT) {
250 		if (msgbuf_write(&c->ibuf.w) <= 0 && errno != EAGAIN)
251 			return control_close(c);
252 		if (c->throttled && c->ibuf.w.queued < CTL_MSG_LOW_MARK) {
253 			if (imsg_ctl_rde(IMSG_XON, 0, c->ibuf.pid, NULL, 0) !=
254 			    -1)
255 				c->throttled = 0;
256 		}
257 	}
258 
259 	if (!(pfd->revents & POLLIN))
260 		return (0);
261 
262 	if (((n = imsg_read_nofd(&c->ibuf)) == -1 && errno != EAGAIN) ||
263 	    n == 0)
264 		return control_close(c);
265 
266 	for (;;) {
267 		if ((n = imsg_get(&c->ibuf, &imsg)) == -1)
268 			return control_close(c);
269 
270 		if (n == 0)
271 			break;
272 
273 		if (c->restricted) {
274 			switch (imsg.hdr.type) {
275 			case IMSG_CTL_SHOW_NEIGHBOR:
276 			case IMSG_CTL_SHOW_NEXTHOP:
277 			case IMSG_CTL_SHOW_INTERFACE:
278 			case IMSG_CTL_SHOW_RIB_MEM:
279 			case IMSG_CTL_SHOW_TERSE:
280 			case IMSG_CTL_SHOW_TIMER:
281 			case IMSG_CTL_SHOW_NETWORK:
282 			case IMSG_CTL_SHOW_FLOWSPEC:
283 			case IMSG_CTL_SHOW_RIB:
284 			case IMSG_CTL_SHOW_RIB_PREFIX:
285 			case IMSG_CTL_SHOW_SET:
286 			case IMSG_CTL_SHOW_RTR:
287 				break;
288 			default:
289 				/* clear imsg type to prevent processing */
290 				imsg.hdr.type = IMSG_NONE;
291 				control_result(c, CTL_RES_DENIED);
292 				break;
293 			}
294 		}
295 
296 		switch (imsg.hdr.type) {
297 		case IMSG_NONE:
298 			/* message was filtered out, nothing to do */
299 			break;
300 		case IMSG_CTL_FIB_COUPLE:
301 		case IMSG_CTL_FIB_DECOUPLE:
302 			imsg_ctl_parent(imsg.hdr.type, imsg.hdr.peerid,
303 			    0, NULL, 0);
304 			break;
305 		case IMSG_CTL_SHOW_TERSE:
306 			RB_FOREACH(p, peer_head, peers)
307 				imsg_compose(&c->ibuf, IMSG_CTL_SHOW_NEIGHBOR,
308 				    0, 0, -1, p, sizeof(struct peer));
309 			imsg_compose(&c->ibuf, IMSG_CTL_END, 0, 0, -1, NULL, 0);
310 			break;
311 		case IMSG_CTL_SHOW_NEIGHBOR:
312 			c->ibuf.pid = imsg.hdr.pid;
313 
314 			if (imsg.hdr.len == IMSG_HEADER_SIZE +
315 			    sizeof(struct ctl_neighbor)) {
316 				neighbor = imsg.data;
317 				neighbor->descr[PEER_DESCR_LEN - 1] = 0;
318 			} else {
319 				neighbor = NULL;
320 			}
321 			matched = 0;
322 			RB_FOREACH(p, peer_head, peers) {
323 				if (!peer_matched(p, neighbor))
324 					continue;
325 
326 				matched = 1;
327 				if (!neighbor || !neighbor->show_timers) {
328 					imsg_ctl_rde(imsg.hdr.type, p->conf.id,
329 					    imsg.hdr.pid, NULL, 0);
330 				} else {
331 					u_int			 i;
332 					time_t			 d;
333 					struct ctl_timer	 ct;
334 
335 					imsg_compose(&c->ibuf,
336 					    IMSG_CTL_SHOW_NEIGHBOR,
337 					    0, 0, -1, p, sizeof(*p));
338 					for (i = 1; i < Timer_Max; i++) {
339 						if (!timer_running(&p->timers,
340 						    i, &d))
341 							continue;
342 						ct.type = i;
343 						ct.val = d;
344 						imsg_compose(&c->ibuf,
345 						    IMSG_CTL_SHOW_TIMER,
346 						    0, 0, -1, &ct, sizeof(ct));
347 					}
348 				}
349 			}
350 			if (!matched && RB_EMPTY(peers)) {
351 				control_result(c, CTL_RES_NOSUCHPEER);
352 			} else if (!neighbor || !neighbor->show_timers) {
353 				imsg_ctl_rde(IMSG_CTL_END, 0, imsg.hdr.pid,
354 				    NULL, 0);
355 			} else {
356 				imsg_compose(&c->ibuf, IMSG_CTL_END, 0, 0, -1,
357 				    NULL, 0);
358 			}
359 			break;
360 		case IMSG_CTL_NEIGHBOR_UP:
361 		case IMSG_CTL_NEIGHBOR_DOWN:
362 		case IMSG_CTL_NEIGHBOR_CLEAR:
363 		case IMSG_CTL_NEIGHBOR_RREFRESH:
364 		case IMSG_CTL_NEIGHBOR_DESTROY:
365 			if (imsg.hdr.len != IMSG_HEADER_SIZE +
366 			    sizeof(struct ctl_neighbor)) {
367 				log_warnx("got IMSG_CTL_NEIGHBOR_ with "
368 				    "wrong length");
369 				break;
370 			}
371 
372 			neighbor = imsg.data;
373 			neighbor->descr[PEER_DESCR_LEN - 1] = 0;
374 
375 			matched = 0;
376 			RB_FOREACH(p, peer_head, peers) {
377 				if (!peer_matched(p, neighbor))
378 					continue;
379 
380 				matched = 1;
381 
382 				switch (imsg.hdr.type) {
383 				case IMSG_CTL_NEIGHBOR_UP:
384 					bgp_fsm(p, EVNT_START);
385 					p->conf.down = 0;
386 					p->conf.reason[0] = '\0';
387 					p->IdleHoldTime =
388 					    INTERVAL_IDLE_HOLD_INITIAL;
389 					p->errcnt = 0;
390 					control_result(c, CTL_RES_OK);
391 					break;
392 				case IMSG_CTL_NEIGHBOR_DOWN:
393 					p->conf.down = 1;
394 					strlcpy(p->conf.reason,
395 					    neighbor->reason,
396 					    sizeof(neighbor->reason));
397 					session_stop(p, ERR_CEASE_ADMIN_DOWN);
398 					control_result(c, CTL_RES_OK);
399 					break;
400 				case IMSG_CTL_NEIGHBOR_CLEAR:
401 					strlcpy(p->conf.reason,
402 					    neighbor->reason,
403 					    sizeof(neighbor->reason));
404 					p->IdleHoldTime =
405 					    INTERVAL_IDLE_HOLD_INITIAL;
406 					p->errcnt = 0;
407 					if (!p->conf.down) {
408 						session_stop(p,
409 						    ERR_CEASE_ADMIN_RESET);
410 						timer_set(&p->timers,
411 						    Timer_IdleHold,
412 						    SESSION_CLEAR_DELAY);
413 					} else {
414 						session_stop(p,
415 						    ERR_CEASE_ADMIN_DOWN);
416 					}
417 					control_result(c, CTL_RES_OK);
418 					break;
419 				case IMSG_CTL_NEIGHBOR_RREFRESH:
420 					if (session_neighbor_rrefresh(p))
421 						control_result(c,
422 						    CTL_RES_NOCAP);
423 					else
424 						control_result(c, CTL_RES_OK);
425 					break;
426 				case IMSG_CTL_NEIGHBOR_DESTROY:
427 					if (!p->template)
428 						control_result(c,
429 						    CTL_RES_BADPEER);
430 					else if (p->state != STATE_IDLE)
431 						control_result(c,
432 						    CTL_RES_BADSTATE);
433 					else {
434 						/*
435 						 * Mark as deleted, will be
436 						 * collected on next poll loop.
437 						 */
438 						p->reconf_action =
439 						    RECONF_DELETE;
440 						control_result(c, CTL_RES_OK);
441 					}
442 					break;
443 				default:
444 					fatal("king bula wants more humppa");
445 				}
446 			}
447 			if (!matched)
448 				control_result(c, CTL_RES_NOSUCHPEER);
449 			break;
450 		case IMSG_CTL_RELOAD:
451 		case IMSG_CTL_SHOW_INTERFACE:
452 		case IMSG_CTL_SHOW_FIB_TABLES:
453 		case IMSG_CTL_SHOW_RTR:
454 			c->ibuf.pid = imsg.hdr.pid;
455 			imsg_ctl_parent(imsg.hdr.type, 0, imsg.hdr.pid,
456 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
457 			break;
458 		case IMSG_CTL_KROUTE:
459 		case IMSG_CTL_KROUTE_ADDR:
460 		case IMSG_CTL_SHOW_NEXTHOP:
461 			c->ibuf.pid = imsg.hdr.pid;
462 			imsg_ctl_parent(imsg.hdr.type, imsg.hdr.peerid,
463 			    imsg.hdr.pid, imsg.data, imsg.hdr.len -
464 			    IMSG_HEADER_SIZE);
465 			break;
466 		case IMSG_CTL_SHOW_RIB:
467 		case IMSG_CTL_SHOW_RIB_PREFIX:
468 			if (imsg.hdr.len != IMSG_HEADER_SIZE +
469 			    sizeof(struct ctl_show_rib_request)) {
470 				log_warnx("got IMSG_CTL_SHOW_RIB with "
471 				    "wrong length");
472 				break;
473 			}
474 
475 			ribreq = imsg.data;
476 			neighbor = &ribreq->neighbor;
477 			neighbor->descr[PEER_DESCR_LEN - 1] = 0;
478 
479 			/* check if at least one neighbor exists */
480 			RB_FOREACH(p, peer_head, peers)
481 				if (peer_matched(p, neighbor))
482 					break;
483 			if (p == NULL && RB_EMPTY(peers)) {
484 				control_result(c, CTL_RES_NOSUCHPEER);
485 				break;
486 			}
487 
488 			if ((imsg.hdr.type == IMSG_CTL_SHOW_RIB_PREFIX)
489 			    && (ribreq->prefix.aid == AID_UNSPEC)) {
490 				/* malformed request, must specify af */
491 				control_result(c, CTL_RES_PARSE_ERROR);
492 				break;
493 			}
494 
495 			c->ibuf.pid = imsg.hdr.pid;
496 			c->terminate = 1;
497 
498 			imsg_ctl_rde(imsg.hdr.type, 0, imsg.hdr.pid,
499 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
500 			break;
501 		case IMSG_CTL_SHOW_NETWORK:
502 		case IMSG_CTL_SHOW_FLOWSPEC:
503 			c->terminate = 1;
504 			/* FALLTHROUGH */
505 		case IMSG_CTL_SHOW_RIB_MEM:
506 		case IMSG_CTL_SHOW_SET:
507 			c->ibuf.pid = imsg.hdr.pid;
508 			imsg_ctl_rde(imsg.hdr.type, 0, imsg.hdr.pid,
509 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
510 			break;
511 		case IMSG_NETWORK_ADD:
512 		case IMSG_NETWORK_ASPATH:
513 		case IMSG_NETWORK_ATTR:
514 		case IMSG_NETWORK_REMOVE:
515 		case IMSG_NETWORK_FLUSH:
516 		case IMSG_NETWORK_DONE:
517 		case IMSG_FLOWSPEC_ADD:
518 		case IMSG_FLOWSPEC_REMOVE:
519 		case IMSG_FLOWSPEC_DONE:
520 		case IMSG_FLOWSPEC_FLUSH:
521 		case IMSG_FILTER_SET:
522 			imsg_ctl_rde(imsg.hdr.type, 0, 0,
523 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
524 			break;
525 		case IMSG_CTL_LOG_VERBOSE:
526 			if (imsg.hdr.len != IMSG_HEADER_SIZE +
527 			    sizeof(verbose))
528 				break;
529 
530 			/* forward to other processes */
531 			imsg_ctl_parent(imsg.hdr.type, 0, imsg.hdr.pid,
532 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
533 			imsg_ctl_rde(imsg.hdr.type, 0, imsg.hdr.pid,
534 			    imsg.data, imsg.hdr.len - IMSG_HEADER_SIZE);
535 
536 			memcpy(&verbose, imsg.data, sizeof(verbose));
537 			log_setverbose(verbose);
538 			break;
539 		default:
540 			break;
541 		}
542 		imsg_free(&imsg);
543 	}
544 
545 	return (0);
546 }
547 
548 int
549 control_imsg_relay(struct imsg *imsg, struct peer *p)
550 {
551 	struct ctl_conn	*c;
552 
553 	if ((c = control_connbypid(imsg->hdr.pid)) == NULL)
554 		return (0);
555 
556 	/* special handling for peers since only the stats are sent from RDE */
557 	if (imsg->hdr.type == IMSG_CTL_SHOW_NEIGHBOR) {
558 		struct rde_peer_stats stats;
559 
560 		if (imsg->hdr.len > IMSG_HEADER_SIZE + sizeof(stats)) {
561 			log_warnx("wrong imsg len");
562 			return (0);
563 		}
564 		if (p == NULL) {
565 			log_warnx("no such peer: id=%u", imsg->hdr.peerid);
566 			return (0);
567 		}
568 		memcpy(&stats, imsg->data, sizeof(stats));
569 		p->stats.prefix_cnt = stats.prefix_cnt;
570 		p->stats.prefix_out_cnt = stats.prefix_out_cnt;
571 		p->stats.prefix_rcvd_update = stats.prefix_rcvd_update;
572 		p->stats.prefix_rcvd_withdraw = stats.prefix_rcvd_withdraw;
573 		p->stats.prefix_rcvd_eor = stats.prefix_rcvd_eor;
574 		p->stats.prefix_sent_update = stats.prefix_sent_update;
575 		p->stats.prefix_sent_withdraw = stats.prefix_sent_withdraw;
576 		p->stats.prefix_sent_eor = stats.prefix_sent_eor;
577 		p->stats.pending_update = stats.pending_update;
578 		p->stats.pending_withdraw = stats.pending_withdraw;
579 
580 		return (imsg_compose(&c->ibuf, imsg->hdr.type, 0,
581 		    imsg->hdr.pid, -1, p, sizeof(*p)));
582 	}
583 
584 	/* if command finished no need to send exit message */
585 	if (imsg->hdr.type == IMSG_CTL_END || imsg->hdr.type == IMSG_CTL_RESULT)
586 		c->terminate = 0;
587 
588 	if (!c->throttled && c->ibuf.w.queued > CTL_MSG_HIGH_MARK) {
589 		if (imsg_ctl_rde(IMSG_XOFF, 0, imsg->hdr.pid, NULL, 0) != -1)
590 			c->throttled = 1;
591 	}
592 
593 	return (imsg_compose(&c->ibuf, imsg->hdr.type, 0, imsg->hdr.pid, -1,
594 	    imsg->data, imsg->hdr.len - IMSG_HEADER_SIZE));
595 }
596 
597 void
598 control_result(struct ctl_conn *c, u_int code)
599 {
600 	imsg_compose(&c->ibuf, IMSG_CTL_RESULT, 0, c->ibuf.pid, -1,
601 	    &code, sizeof(code));
602 }
603 
604 /* This should go into libutil, from smtpd/mproc.c */
605 ssize_t
606 imsg_read_nofd(struct imsgbuf *ibuf)
607 {
608 	ssize_t	 n;
609 	char	*buf;
610 	size_t	 len;
611 
612 	buf = ibuf->r.buf + ibuf->r.wpos;
613 	len = sizeof(ibuf->r.buf) - ibuf->r.wpos;
614 
615 	while ((n = recv(ibuf->fd, buf, len, 0)) == -1) {
616 		if (errno != EINTR)
617 			return (n);
618 	}
619 
620 	ibuf->r.wpos += n;
621 	return (n);
622 }
623