1 /*
2  * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
3  * Copyright (c) 2020 Ori Bernstein <ori@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/types.h>
19 #include <sys/queue.h>
20 #include <sys/uio.h>
21 #include <sys/wait.h>
22 
23 #include <ctype.h>
24 #include <limits.h>
25 #include <signal.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <errno.h>
30 #include <stdint.h>
31 #include <poll.h>
32 #include <imsg.h>
33 #include <sha1.h>
34 #include <unistd.h>
35 #include <zlib.h>
36 #include <time.h>
37 
38 #include "got_object.h"
39 #include "got_error.h"
40 #include "got_path.h"
41 #include "got_repository.h"
42 
43 #include "got_lib_sha1.h"
44 #include "got_lib_delta.h"
45 #include "got_lib_inflate.h"
46 #include "got_lib_object.h"
47 #include "got_lib_object_parse.h"
48 #include "got_lib_privsep.h"
49 #include "got_lib_pack.h"
50 
51 #ifndef MIN
52 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
53 #endif
54 
55 #ifndef nitems
56 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
57 #endif
58 
59 static const struct got_error *
60 poll_fd(int fd, int events, int timeout)
61 {
62 	struct pollfd pfd[1];
63 	struct timespec ts;
64 	sigset_t sigset;
65 	int n;
66 
67 	pfd[0].fd = fd;
68 	pfd[0].events = events;
69 
70 	ts.tv_sec = timeout;
71 	ts.tv_nsec = 0;
72 
73 	if (sigemptyset(&sigset) == -1)
74 		return got_error_from_errno("sigemptyset");
75 	if (sigaddset(&sigset, SIGWINCH) == -1)
76 		return got_error_from_errno("sigaddset");
77 
78 	n = ppoll(pfd, 1, timeout == INFTIM ? NULL : &ts, &sigset);
79 	if (n == -1)
80 		return got_error_from_errno("ppoll");
81 	if (n == 0)
82 		return got_error(GOT_ERR_TIMEOUT);
83 	if (pfd[0].revents & (POLLERR | POLLNVAL))
84 		return got_error_from_errno("poll error");
85 	if (pfd[0].revents & (events | POLLHUP))
86 		return NULL;
87 
88 	return got_error(GOT_ERR_INTERRUPT);
89 }
90 
91 static const struct got_error *
92 read_imsg(struct imsgbuf *ibuf)
93 {
94 	const struct got_error *err;
95 	size_t n;
96 
97 	err = poll_fd(ibuf->fd, POLLIN, INFTIM);
98 	if (err)
99 		return err;
100 
101 	n = imsg_read(ibuf);
102 	if (n == -1) {
103 		if (errno == EAGAIN) /* Could be a file-descriptor leak. */
104 			return got_error(GOT_ERR_PRIVSEP_NO_FD);
105 		return got_error(GOT_ERR_PRIVSEP_READ);
106 	}
107 	if (n == 0)
108 		return got_error(GOT_ERR_PRIVSEP_PIPE);
109 
110 	return NULL;
111 }
112 
113 const struct got_error *
114 got_privsep_wait_for_child(pid_t pid)
115 {
116 	int child_status;
117 
118 	if (waitpid(pid, &child_status, 0) == -1)
119 		return got_error_from_errno("waitpid");
120 
121 	if (!WIFEXITED(child_status))
122 		return got_error(GOT_ERR_PRIVSEP_DIED);
123 
124 	if (WEXITSTATUS(child_status) != 0)
125 		return got_error(GOT_ERR_PRIVSEP_EXIT);
126 
127 	return NULL;
128 }
129 
130 static const struct got_error *
131 recv_imsg_error(struct imsg *imsg, size_t datalen)
132 {
133 	struct got_imsg_error *ierr;
134 
135 	if (datalen != sizeof(*ierr))
136 		return got_error(GOT_ERR_PRIVSEP_LEN);
137 
138 	ierr = imsg->data;
139 	if (ierr->code == GOT_ERR_ERRNO) {
140 		static struct got_error serr;
141 		serr.code = GOT_ERR_ERRNO;
142 		serr.msg = strerror(ierr->errno_code);
143 		return &serr;
144 	}
145 
146 	return got_error(ierr->code);
147 }
148 
149 const struct got_error *
150 got_privsep_recv_imsg(struct imsg *imsg, struct imsgbuf *ibuf,
151     size_t min_datalen)
152 {
153 	const struct got_error *err;
154 	ssize_t n;
155 
156 	n = imsg_get(ibuf, imsg);
157 	if (n == -1)
158 		return got_error_from_errno("imsg_get");
159 
160 	while (n == 0) {
161 		err = read_imsg(ibuf);
162 		if (err)
163 			return err;
164 		n = imsg_get(ibuf, imsg);
165 		if (n == -1)
166 			return got_error_from_errno("imsg_get");
167 	}
168 
169 	if (imsg->hdr.len < IMSG_HEADER_SIZE + min_datalen)
170 		return got_error(GOT_ERR_PRIVSEP_LEN);
171 
172 	if (imsg->hdr.type == GOT_IMSG_ERROR) {
173 		size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
174 		return recv_imsg_error(imsg, datalen);
175 	}
176 
177 	return NULL;
178 }
179 
180 /* Attempt to send an error in an imsg. Complain on stderr as a last resort. */
181 void
182 got_privsep_send_error(struct imsgbuf *ibuf, const struct got_error *err)
183 {
184 	const struct got_error *poll_err;
185 	struct got_imsg_error ierr;
186 	int ret;
187 
188 	ierr.code = err->code;
189 	if (err->code == GOT_ERR_ERRNO)
190 		ierr.errno_code = errno;
191 	else
192 		ierr.errno_code = 0;
193 	ret = imsg_compose(ibuf, GOT_IMSG_ERROR, 0, 0, -1, &ierr, sizeof(ierr));
194 	if (ret == -1) {
195 		fprintf(stderr, "%s: error %d \"%s\": imsg_compose: %s\n",
196 		    getprogname(), err->code, err->msg, strerror(errno));
197 		return;
198 	}
199 
200 	poll_err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
201 	if (poll_err) {
202 		fprintf(stderr, "%s: error %d \"%s\": poll: %s\n",
203 		    getprogname(), err->code, err->msg, poll_err->msg);
204 		return;
205 	}
206 
207 	ret = imsg_flush(ibuf);
208 	if (ret == -1) {
209 		fprintf(stderr, "%s: error %d \"%s\": imsg_flush: %s\n",
210 		    getprogname(), err->code, err->msg, strerror(errno));
211 		imsg_clear(ibuf);
212 		return;
213 	}
214 }
215 
216 static const struct got_error *
217 flush_imsg(struct imsgbuf *ibuf)
218 {
219 	const struct got_error *err;
220 
221 	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
222 	if (err)
223 		return err;
224 
225 	if (imsg_flush(ibuf) == -1) {
226 		imsg_clear(ibuf);
227 		return got_error_from_errno("imsg_flush");
228 	}
229 
230 	return NULL;
231 }
232 
233 const struct got_error *
234 got_privsep_flush_imsg(struct imsgbuf *ibuf)
235 {
236 	return flush_imsg(ibuf);
237 }
238 
239 const struct got_error *
240 got_privsep_send_stop(int fd)
241 {
242 	const struct got_error *err = NULL;
243 	struct imsgbuf ibuf;
244 
245 	imsg_init(&ibuf, fd);
246 
247 	if (imsg_compose(&ibuf, GOT_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
248 		return got_error_from_errno("imsg_compose STOP");
249 
250 	err = flush_imsg(&ibuf);
251 	return err;
252 }
253 
254 const struct got_error *
255 got_privsep_send_obj_req(struct imsgbuf *ibuf, int fd,
256     struct got_object_id *id)
257 {
258 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_REQUEST, 0, 0, fd,
259 	    id, sizeof(*id)) == -1)
260 		return got_error_from_errno("imsg_compose OBJECT_REQUEST");
261 
262 	return flush_imsg(ibuf);
263 }
264 
265 const struct got_error *
266 got_privsep_send_raw_obj_req(struct imsgbuf *ibuf, int fd,
267     struct got_object_id *id)
268 {
269 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_REQUEST, 0, 0, fd,
270 	    id, sizeof(*id)) == -1)
271 		return got_error_from_errno("imsg_compose RAW_OBJECT_REQUEST");
272 
273 	return flush_imsg(ibuf);
274 }
275 
276 const struct got_error *
277 got_privsep_send_raw_obj_outfd(struct imsgbuf *ibuf, int outfd)
278 {
279 	const struct got_error *err = NULL;
280 
281 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_OUTFD, 0, 0, outfd, NULL, 0)
282 	    == -1) {
283 		err = got_error_from_errno("imsg_compose RAW_OBJECT_OUTFD");
284 		close(outfd);
285 		return err;
286 	}
287 
288 	return flush_imsg(ibuf);
289 }
290 
291 const struct got_error *
292 got_privsep_send_raw_obj(struct imsgbuf *ibuf, off_t size, size_t hdrlen,
293     uint8_t *data)
294 {
295 	const struct got_error *err = NULL;
296 	struct got_imsg_raw_obj iobj;
297 	size_t len = sizeof(iobj);
298 	struct ibuf *wbuf;
299 
300 	iobj.hdrlen = hdrlen;
301 	iobj.size = size;
302 
303 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX)
304 		len += (size_t)size + hdrlen;
305 
306 	wbuf = imsg_create(ibuf, GOT_IMSG_RAW_OBJECT, 0, 0, len);
307 	if (wbuf == NULL) {
308 		err = got_error_from_errno("imsg_create RAW_OBJECT");
309 		return err;
310 	}
311 
312 	if (imsg_add(wbuf, &iobj, sizeof(iobj)) == -1) {
313 		err = got_error_from_errno("imsg_add RAW_OBJECT");
314 		ibuf_free(wbuf);
315 		return err;
316 	}
317 
318 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
319 		if (imsg_add(wbuf, data, size + hdrlen) == -1) {
320 			err = got_error_from_errno("imsg_add RAW_OBJECT");
321 			ibuf_free(wbuf);
322 			return err;
323 		}
324 	}
325 
326 	wbuf->fd = -1;
327 	imsg_close(ibuf, wbuf);
328 
329 	return flush_imsg(ibuf);
330 }
331 
332 const struct got_error *
333 got_privsep_recv_raw_obj(uint8_t **outbuf, off_t *size, size_t *hdrlen,
334     struct imsgbuf *ibuf)
335 {
336 	const struct got_error *err = NULL;
337 	struct imsg imsg;
338 	struct got_imsg_raw_obj *iobj;
339 	size_t datalen;
340 
341 	*outbuf = NULL;
342 
343 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
344 	if (err)
345 		return err;
346 
347 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
348 
349 	switch (imsg.hdr.type) {
350 	case GOT_IMSG_RAW_OBJECT:
351 		if (datalen < sizeof(*iobj)) {
352 			err = got_error(GOT_ERR_PRIVSEP_LEN);
353 			break;
354 		}
355 		iobj = imsg.data;
356 		*size = iobj->size;
357 		*hdrlen = iobj->hdrlen;
358 
359 		if (datalen == sizeof(*iobj)) {
360 			/* Data has been written to file descriptor. */
361 			break;
362 		}
363 
364 		if (*size + *hdrlen > GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
365 			err = got_error(GOT_ERR_PRIVSEP_LEN);
366 			break;
367 		}
368 
369 		*outbuf = malloc(*size + *hdrlen);
370 		if (*outbuf == NULL) {
371 			err = got_error_from_errno("malloc");
372 			break;
373 		}
374 		memcpy(*outbuf, imsg.data + sizeof(*iobj), *size + *hdrlen);
375 		break;
376 	default:
377 		err = got_error(GOT_ERR_PRIVSEP_MSG);
378 		break;
379 	}
380 
381 	imsg_free(&imsg);
382 
383 	return err;
384 }
385 
386 const struct got_error *
387 got_privsep_send_commit_req(struct imsgbuf *ibuf, int fd,
388     struct got_object_id *id, int pack_idx)
389 {
390 	const struct got_error *err = NULL;
391 	struct got_imsg_packed_object iobj;
392 	void *data;
393 	size_t len;
394 
395 	if (pack_idx != -1) { /* commit is packed */
396 		iobj.idx = pack_idx;
397 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
398 		data = &iobj;
399 		len = sizeof(iobj);
400 	} else {
401 		data = id;
402 		len = sizeof(*id);
403 	}
404 
405 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_REQUEST, 0, 0, fd, data, len)
406 	    == -1) {
407 		err = got_error_from_errno("imsg_compose COMMIT_REQUEST");
408 		close(fd);
409 		return err;
410 	}
411 
412 	return flush_imsg(ibuf);
413 }
414 
415 const struct got_error *
416 got_privsep_send_tree_req(struct imsgbuf *ibuf, int fd,
417     struct got_object_id *id, int pack_idx)
418 {
419 	const struct got_error *err = NULL;
420 	struct ibuf *wbuf;
421 	size_t len;
422 
423 	if (pack_idx != -1)
424 		len = sizeof(struct got_imsg_packed_object);
425 	else
426 		len = sizeof(*id);
427 
428 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_REQUEST, 0, 0, len);
429 	if (wbuf == NULL)
430 		return got_error_from_errno("imsg_create TREE_REQUEST");
431 
432 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
433 		err = got_error_from_errno("imsg_add TREE_REQUEST");
434 		ibuf_free(wbuf);
435 		return err;
436 	}
437 
438 	if (pack_idx != -1) { /* tree is packed */
439 		if (imsg_add(wbuf, &pack_idx, sizeof(pack_idx)) == -1) {
440 			err = got_error_from_errno("imsg_add TREE_REQUEST");
441 			ibuf_free(wbuf);
442 			return err;
443 		}
444 	}
445 
446 	wbuf->fd = fd;
447 	imsg_close(ibuf, wbuf);
448 
449 	return flush_imsg(ibuf);
450 }
451 
452 const struct got_error *
453 got_privsep_send_tag_req(struct imsgbuf *ibuf, int fd,
454     struct got_object_id *id, int pack_idx)
455 {
456 	struct got_imsg_packed_object iobj;
457 	void *data;
458 	size_t len;
459 
460 	if (pack_idx != -1) { /* tag is packed */
461 		iobj.idx = pack_idx;
462 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
463 		data = &iobj;
464 		len = sizeof(iobj);
465 	} else {
466 		data = id;
467 		len = sizeof(*id);
468 	}
469 
470 	if (imsg_compose(ibuf, GOT_IMSG_TAG_REQUEST, 0, 0, fd, data, len)
471 	    == -1)
472 		return got_error_from_errno("imsg_compose TAG_REQUEST");
473 
474 	return flush_imsg(ibuf);
475 }
476 
477 const struct got_error *
478 got_privsep_send_blob_req(struct imsgbuf *ibuf, int infd,
479     struct got_object_id *id, int pack_idx)
480 {
481 	const struct got_error *err = NULL;
482 	struct got_imsg_packed_object iobj;
483 	void *data;
484 	size_t len;
485 
486 	if (pack_idx != -1) { /* blob is packed */
487 		iobj.idx = pack_idx;
488 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
489 		data = &iobj;
490 		len = sizeof(iobj);
491 	} else {
492 		data = id;
493 		len = sizeof(*id);
494 	}
495 
496 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_REQUEST, 0, 0, infd, data, len)
497 	    == -1) {
498 		err = got_error_from_errno("imsg_compose BLOB_REQUEST");
499 		close(infd);
500 		return err;
501 	}
502 
503 	return flush_imsg(ibuf);
504 }
505 
506 const struct got_error *
507 got_privsep_send_blob_outfd(struct imsgbuf *ibuf, int outfd)
508 {
509 	const struct got_error *err = NULL;
510 
511 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_OUTFD, 0, 0, outfd, NULL, 0)
512 	    == -1) {
513 		err = got_error_from_errno("imsg_compose BLOB_OUTFD");
514 		close(outfd);
515 		return err;
516 	}
517 
518 	return flush_imsg(ibuf);
519 }
520 
521 static const struct got_error *
522 send_fd(struct imsgbuf *ibuf, int imsg_code, int fd)
523 {
524 	const struct got_error *err = NULL;
525 
526 	if (imsg_compose(ibuf, imsg_code, 0, 0, fd, NULL, 0) == -1) {
527 		err = got_error_from_errno("imsg_compose TMPFD");
528 		close(fd);
529 		return err;
530 	}
531 
532 	return flush_imsg(ibuf);
533 }
534 
535 const struct got_error *
536 got_privsep_send_tmpfd(struct imsgbuf *ibuf, int fd)
537 {
538 	return send_fd(ibuf, GOT_IMSG_TMPFD, fd);
539 }
540 
541 const struct got_error *
542 got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj)
543 {
544 	struct got_imsg_object iobj;
545 
546 	memcpy(iobj.id, obj->id.sha1, sizeof(iobj.id));
547 	iobj.type = obj->type;
548 	iobj.flags = obj->flags;
549 	iobj.hdrlen = obj->hdrlen;
550 	iobj.size = obj->size;
551 	if (iobj.flags & GOT_OBJ_FLAG_PACKED) {
552 		iobj.pack_offset = obj->pack_offset;
553 		iobj.pack_idx = obj->pack_idx;
554 	}
555 
556 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
557 	    == -1)
558 		return got_error_from_errno("imsg_compose OBJECT");
559 
560 	return flush_imsg(ibuf);
561 }
562 
563 const struct got_error *
564 got_privsep_send_fetch_req(struct imsgbuf *ibuf, int fd,
565     struct got_pathlist_head *have_refs, int fetch_all_branches,
566     struct got_pathlist_head *wanted_branches,
567     struct got_pathlist_head *wanted_refs, int list_refs_only, int verbosity)
568 {
569 	const struct got_error *err = NULL;
570 	struct ibuf *wbuf;
571 	size_t len;
572 	struct got_pathlist_entry *pe;
573 	struct got_imsg_fetch_request fetchreq;
574 
575 	memset(&fetchreq, 0, sizeof(fetchreq));
576 	fetchreq.fetch_all_branches = fetch_all_branches;
577 	fetchreq.list_refs_only = list_refs_only;
578 	fetchreq.verbosity = verbosity;
579 	TAILQ_FOREACH(pe, have_refs, entry)
580 		fetchreq.n_have_refs++;
581 	TAILQ_FOREACH(pe, wanted_branches, entry)
582 		fetchreq.n_wanted_branches++;
583 	TAILQ_FOREACH(pe, wanted_refs, entry)
584 		fetchreq.n_wanted_refs++;
585 	len = sizeof(struct got_imsg_fetch_request);
586 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
587 		close(fd);
588 		return got_error(GOT_ERR_NO_SPACE);
589 	}
590 
591 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_REQUEST, 0, 0, fd,
592 	    &fetchreq, sizeof(fetchreq)) == -1)
593 		return got_error_from_errno(
594 		    "imsg_compose FETCH_SERVER_PROGRESS");
595 
596 	err = flush_imsg(ibuf);
597 	if (err) {
598 		close(fd);
599 		return err;
600 	}
601 	fd = -1;
602 
603 	TAILQ_FOREACH(pe, have_refs, entry) {
604 		const char *name = pe->path;
605 		size_t name_len = pe->path_len;
606 		struct got_object_id *id = pe->data;
607 
608 		len = sizeof(struct got_imsg_fetch_have_ref) + name_len;
609 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_HAVE_REF, 0, 0, len);
610 		if (wbuf == NULL)
611 			return got_error_from_errno("imsg_create FETCH_HAVE_REF");
612 
613 		/* Keep in sync with struct got_imsg_fetch_have_ref! */
614 		if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1) {
615 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
616 			ibuf_free(wbuf);
617 			return err;
618 		}
619 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
620 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
621 			ibuf_free(wbuf);
622 			return err;
623 		}
624 		if (imsg_add(wbuf, name, name_len) == -1) {
625 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
626 			ibuf_free(wbuf);
627 			return err;
628 		}
629 
630 		wbuf->fd = -1;
631 		imsg_close(ibuf, wbuf);
632 		err = flush_imsg(ibuf);
633 		if (err)
634 			return err;
635 	}
636 
637 	TAILQ_FOREACH(pe, wanted_branches, entry) {
638 		const char *name = pe->path;
639 		size_t name_len = pe->path_len;
640 
641 		len = sizeof(struct got_imsg_fetch_wanted_branch) + name_len;
642 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_BRANCH, 0, 0,
643 		    len);
644 		if (wbuf == NULL)
645 			return got_error_from_errno(
646 			    "imsg_create FETCH_WANTED_BRANCH");
647 
648 		/* Keep in sync with struct got_imsg_fetch_wanted_branch! */
649 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
650 			err = got_error_from_errno(
651 			    "imsg_add FETCH_WANTED_BRANCH");
652 			ibuf_free(wbuf);
653 			return err;
654 		}
655 		if (imsg_add(wbuf, name, name_len) == -1) {
656 			err = got_error_from_errno(
657 			    "imsg_add FETCH_WANTED_BRANCH");
658 			ibuf_free(wbuf);
659 			return err;
660 		}
661 
662 		wbuf->fd = -1;
663 		imsg_close(ibuf, wbuf);
664 		err = flush_imsg(ibuf);
665 		if (err)
666 			return err;
667 	}
668 
669 	TAILQ_FOREACH(pe, wanted_refs, entry) {
670 		const char *name = pe->path;
671 		size_t name_len = pe->path_len;
672 
673 		len = sizeof(struct got_imsg_fetch_wanted_ref) + name_len;
674 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_REF, 0, 0,
675 		    len);
676 		if (wbuf == NULL)
677 			return got_error_from_errno(
678 			    "imsg_create FETCH_WANTED_REF");
679 
680 		/* Keep in sync with struct got_imsg_fetch_wanted_ref! */
681 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
682 			err = got_error_from_errno(
683 			    "imsg_add FETCH_WANTED_REF");
684 			ibuf_free(wbuf);
685 			return err;
686 		}
687 		if (imsg_add(wbuf, name, name_len) == -1) {
688 			err = got_error_from_errno(
689 			    "imsg_add FETCH_WANTED_REF");
690 			ibuf_free(wbuf);
691 			return err;
692 		}
693 
694 		wbuf->fd = -1;
695 		imsg_close(ibuf, wbuf);
696 		err = flush_imsg(ibuf);
697 		if (err)
698 			return err;
699 	}
700 
701 
702 	return NULL;
703 
704 }
705 
706 const struct got_error *
707 got_privsep_send_fetch_outfd(struct imsgbuf *ibuf, int fd)
708 {
709 	return send_fd(ibuf, GOT_IMSG_FETCH_OUTFD, fd);
710 }
711 
712 const struct got_error *
713 got_privsep_recv_fetch_progress(int *done, struct got_object_id **id,
714     char **refname, struct got_pathlist_head *symrefs, char **server_progress,
715     off_t *packfile_size, uint8_t *pack_sha1, struct imsgbuf *ibuf)
716 {
717 	const struct got_error *err = NULL;
718 	struct imsg imsg;
719 	size_t datalen;
720 	struct got_imsg_fetch_symrefs *isymrefs = NULL;
721 	size_t n, remain;
722 	off_t off;
723 	int i;
724 
725 	*done = 0;
726 	*id = NULL;
727 	*refname = NULL;
728 	*server_progress = NULL;
729 	*packfile_size = 0;
730 	memset(pack_sha1, 0, SHA1_DIGEST_LENGTH);
731 
732 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
733 	if (err)
734 		return err;
735 
736 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
737 	switch (imsg.hdr.type) {
738 	case GOT_IMSG_ERROR:
739 		if (datalen < sizeof(struct got_imsg_error)) {
740 			err = got_error(GOT_ERR_PRIVSEP_LEN);
741 			break;
742 		}
743 		err = recv_imsg_error(&imsg, datalen);
744 		break;
745 	case GOT_IMSG_FETCH_SYMREFS:
746 		if (datalen < sizeof(*isymrefs)) {
747 			err = got_error(GOT_ERR_PRIVSEP_LEN);
748 			break;
749 		}
750 		if (isymrefs != NULL) {
751 			err = got_error(GOT_ERR_PRIVSEP_MSG);
752 			break;
753 		}
754 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
755 		off = sizeof(*isymrefs);
756 		remain = datalen - off;
757 		for (n = 0; n < isymrefs->nsymrefs; n++) {
758 			struct got_imsg_fetch_symref *s;
759 			char *name, *target;
760 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
761 				err = got_error(GOT_ERR_PRIVSEP_LEN);
762 				goto done;
763 			}
764 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
765 			off += sizeof(*s);
766 			remain -= sizeof(*s);
767 			if (remain < s->name_len) {
768 				err = got_error(GOT_ERR_PRIVSEP_LEN);
769 				goto done;
770 			}
771 			name = strndup(imsg.data + off, s->name_len);
772 			if (name == NULL) {
773 				err = got_error_from_errno("strndup");
774 				goto done;
775 			}
776 			off += s->name_len;
777 			remain -= s->name_len;
778 			if (remain < s->target_len) {
779 				err = got_error(GOT_ERR_PRIVSEP_LEN);
780 				free(name);
781 				goto done;
782 			}
783 			target = strndup(imsg.data + off, s->target_len);
784 			if (target == NULL) {
785 				err = got_error_from_errno("strndup");
786 				free(name);
787 				goto done;
788 			}
789 			off += s->target_len;
790 			remain -= s->target_len;
791 			err = got_pathlist_append(symrefs, name, target);
792 			if (err) {
793 				free(name);
794 				free(target);
795 				goto done;
796 			}
797 		}
798 		break;
799 	case GOT_IMSG_FETCH_REF:
800 		if (datalen <= SHA1_DIGEST_LENGTH) {
801 			err = got_error(GOT_ERR_PRIVSEP_MSG);
802 			break;
803 		}
804 		*id = malloc(sizeof(**id));
805 		if (*id == NULL) {
806 			err = got_error_from_errno("malloc");
807 			break;
808 		}
809 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
810 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
811 		    datalen - SHA1_DIGEST_LENGTH);
812 		if (*refname == NULL) {
813 			err = got_error_from_errno("strndup");
814 			break;
815 		}
816 		break;
817 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
818 		if (datalen == 0) {
819 			err = got_error(GOT_ERR_PRIVSEP_LEN);
820 			break;
821 		}
822 		*server_progress = strndup(imsg.data, datalen);
823 		if (*server_progress == NULL) {
824 			err = got_error_from_errno("strndup");
825 			break;
826 		}
827 		for (i = 0; i < datalen; i++) {
828 			if (!isprint((unsigned char)(*server_progress)[i]) &&
829 			    !isspace((unsigned char)(*server_progress)[i])) {
830 				err = got_error(GOT_ERR_PRIVSEP_MSG);
831 				free(*server_progress);
832 				*server_progress = NULL;
833 				goto done;
834 			}
835 		}
836 		break;
837 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
838 		if (datalen < sizeof(*packfile_size)) {
839 			err = got_error(GOT_ERR_PRIVSEP_MSG);
840 			break;
841 		}
842 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
843 		break;
844 	case GOT_IMSG_FETCH_DONE:
845 		if (datalen != SHA1_DIGEST_LENGTH) {
846 			err = got_error(GOT_ERR_PRIVSEP_MSG);
847 			break;
848 		}
849 		memcpy(pack_sha1, imsg.data, SHA1_DIGEST_LENGTH);
850 		*done = 1;
851 		break;
852 	default:
853 		err = got_error(GOT_ERR_PRIVSEP_MSG);
854 		break;
855 	}
856 done:
857 	if (err) {
858 		free(*id);
859 		*id = NULL;
860 		free(*refname);
861 		*refname = NULL;
862 	}
863 	imsg_free(&imsg);
864 	return err;
865 }
866 
867 static const struct got_error *
868 send_send_ref(const char *name, size_t name_len, struct got_object_id *id,
869     int delete, struct imsgbuf *ibuf)
870 {
871 	const struct got_error *err = NULL;
872 	size_t len;
873 	struct ibuf *wbuf;
874 
875 	len = sizeof(struct got_imsg_send_ref) + name_len;
876 	wbuf = imsg_create(ibuf, GOT_IMSG_SEND_REF, 0, 0, len);
877 	if (wbuf == NULL)
878 		return got_error_from_errno("imsg_create SEND_REF");
879 
880 	/* Keep in sync with struct got_imsg_send_ref! */
881 	if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1) {
882 		err = got_error_from_errno("imsg_add SEND_REF");
883 		ibuf_free(wbuf);
884 		return err;
885 	}
886 	if (imsg_add(wbuf, &delete, sizeof(delete)) == -1) {
887 		err = got_error_from_errno("imsg_add SEND_REF");
888 		ibuf_free(wbuf);
889 		return err;
890 	}
891 	if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
892 		err = got_error_from_errno("imsg_add SEND_REF");
893 		ibuf_free(wbuf);
894 		return err;
895 	}
896 	if (imsg_add(wbuf, name, name_len) == -1) {
897 		err = got_error_from_errno("imsg_add SEND_REF");
898 		ibuf_free(wbuf);
899 		return err;
900 	}
901 
902 	wbuf->fd = -1;
903 	imsg_close(ibuf, wbuf);
904 	return flush_imsg(ibuf);
905 }
906 
907 const struct got_error *
908 got_privsep_send_send_req(struct imsgbuf *ibuf, int fd,
909     struct got_pathlist_head *have_refs,
910     struct got_pathlist_head *delete_refs,
911     int verbosity)
912 {
913 	const struct got_error *err = NULL;
914 	struct got_pathlist_entry *pe;
915 	struct got_imsg_send_request sendreq;
916 	struct got_object_id zero_id;
917 
918 	memset(&zero_id, 0, sizeof(zero_id));
919 	memset(&sendreq, 0, sizeof(sendreq));
920 	sendreq.verbosity = verbosity;
921 	TAILQ_FOREACH(pe, have_refs, entry)
922 		sendreq.nrefs++;
923 	TAILQ_FOREACH(pe, delete_refs, entry)
924 		sendreq.nrefs++;
925 	if (imsg_compose(ibuf, GOT_IMSG_SEND_REQUEST, 0, 0, fd,
926 	    &sendreq, sizeof(sendreq)) == -1) {
927 		err = got_error_from_errno(
928 		    "imsg_compose FETCH_SERVER_PROGRESS");
929 		goto done;
930 	}
931 
932 	err = flush_imsg(ibuf);
933 	if (err)
934 		goto done;
935 	fd = -1;
936 
937 	TAILQ_FOREACH(pe, have_refs, entry) {
938 		const char *name = pe->path;
939 		size_t name_len = pe->path_len;
940 		struct got_object_id *id = pe->data;
941 		err = send_send_ref(name, name_len, id, 0, ibuf);
942 		if (err)
943 			goto done;
944 	}
945 
946 	TAILQ_FOREACH(pe, delete_refs, entry) {
947 		const char *name = pe->path;
948 		size_t name_len = pe->path_len;
949 		err = send_send_ref(name, name_len, &zero_id, 1, ibuf);
950 		if (err)
951 			goto done;
952 	}
953 done:
954 	if (fd != -1 && close(fd) == -1 && err == NULL)
955 		err = got_error_from_errno("close");
956 	return err;
957 
958 }
959 
960 const struct got_error *
961 got_privsep_recv_send_remote_refs(struct got_pathlist_head *remote_refs,
962     struct imsgbuf *ibuf)
963 {
964 	const struct got_error *err = NULL;
965 	struct imsg imsg;
966 	size_t datalen;
967 	int done = 0;
968 	struct got_imsg_send_remote_ref iremote_ref;
969 	struct got_object_id *id = NULL;
970 	char *refname = NULL;
971 	struct got_pathlist_entry *new;
972 
973 	while (!done) {
974 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
975 		if (err)
976 			return err;
977 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
978 		switch (imsg.hdr.type) {
979 		case GOT_IMSG_ERROR:
980 			if (datalen < sizeof(struct got_imsg_error)) {
981 				err = got_error(GOT_ERR_PRIVSEP_LEN);
982 				goto done;
983 			}
984 			err = recv_imsg_error(&imsg, datalen);
985 			goto done;
986 		case GOT_IMSG_SEND_REMOTE_REF:
987 			if (datalen < sizeof(iremote_ref)) {
988 				err = got_error(GOT_ERR_PRIVSEP_MSG);
989 				goto done;
990 			}
991 			memcpy(&iremote_ref, imsg.data, sizeof(iremote_ref));
992 			if (datalen != sizeof(iremote_ref) +
993 			    iremote_ref.name_len) {
994 				err = got_error(GOT_ERR_PRIVSEP_MSG);
995 				goto done;
996 			}
997 			id = malloc(sizeof(*id));
998 			if (id == NULL) {
999 				err = got_error_from_errno("malloc");
1000 				goto done;
1001 			}
1002 			memcpy(id->sha1, iremote_ref.id, SHA1_DIGEST_LENGTH);
1003 			refname = strndup(imsg.data + sizeof(iremote_ref),
1004 			    datalen - sizeof(iremote_ref));
1005 			if (refname == NULL) {
1006 				err = got_error_from_errno("strndup");
1007 				goto done;
1008 			}
1009 			err = got_pathlist_insert(&new, remote_refs,
1010 			    refname, id);
1011 			if (err)
1012 				goto done;
1013 			if (new == NULL) { /* duplicate which wasn't inserted */
1014 				free(id);
1015 				free(refname);
1016 			}
1017 			id = NULL;
1018 			refname = NULL;
1019 			break;
1020 		case GOT_IMSG_SEND_PACK_REQUEST:
1021 			if (datalen != 0) {
1022 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1023 				goto done;
1024 			}
1025 			/* got-send-pack is now waiting for a pack file. */
1026 			done = 1;
1027 			break;
1028 		default:
1029 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1030 			break;
1031 		}
1032 	}
1033 done:
1034 	free(id);
1035 	free(refname);
1036 	imsg_free(&imsg);
1037 	return err;
1038 }
1039 
1040 const struct got_error *
1041 got_privsep_send_packfd(struct imsgbuf *ibuf, int fd)
1042 {
1043 	return send_fd(ibuf, GOT_IMSG_SEND_PACKFD, fd);
1044 }
1045 
1046 const struct got_error *
1047 got_privsep_recv_send_progress(int *done, off_t *bytes_sent,
1048     int *success, char **refname, struct imsgbuf *ibuf)
1049 {
1050 	const struct got_error *err = NULL;
1051 	struct imsg imsg;
1052 	size_t datalen;
1053 	struct got_imsg_send_ref_status iref_status;
1054 
1055 	/* Do not reset the current value of 'bytes_sent', it accumulates. */
1056 	*done = 0;
1057 	*success = 0;
1058 	*refname = NULL;
1059 
1060 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1061 	if (err)
1062 		return err;
1063 
1064 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1065 	switch (imsg.hdr.type) {
1066 	case GOT_IMSG_ERROR:
1067 		if (datalen < sizeof(struct got_imsg_error)) {
1068 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1069 			break;
1070 		}
1071 		err = recv_imsg_error(&imsg, datalen);
1072 		break;
1073 	case GOT_IMSG_SEND_UPLOAD_PROGRESS:
1074 		if (datalen < sizeof(*bytes_sent)) {
1075 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1076 			break;
1077 		}
1078 		memcpy(bytes_sent, imsg.data, sizeof(*bytes_sent));
1079 		break;
1080 	case GOT_IMSG_SEND_REF_STATUS:
1081 		if (datalen < sizeof(iref_status)) {
1082 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1083 			break;
1084 		}
1085 		memcpy(&iref_status, imsg.data, sizeof(iref_status));
1086 		if (datalen != sizeof(iref_status) + iref_status.name_len) {
1087 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1088 			break;
1089 		}
1090 		*success = iref_status.success;
1091 		*refname = strndup(imsg.data + sizeof(iref_status),
1092 		    iref_status.name_len);
1093 		break;
1094 	case GOT_IMSG_SEND_DONE:
1095 		if (datalen != 0) {
1096 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1097 			break;
1098 		}
1099 		*done = 1;
1100 		break;
1101 	default:
1102 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1103 		break;
1104 	}
1105 
1106 	imsg_free(&imsg);
1107 	return err;
1108 }
1109 
1110 const struct got_error *
1111 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_sha1,
1112     int fd)
1113 {
1114 	const struct got_error *err = NULL;
1115 
1116 	/* Keep in sync with struct got_imsg_index_pack_request */
1117 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
1118 	    pack_sha1, SHA1_DIGEST_LENGTH) == -1) {
1119 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
1120 		close(fd);
1121 		return err;
1122 	}
1123 	return flush_imsg(ibuf);
1124 }
1125 
1126 const struct got_error *
1127 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
1128 {
1129 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
1130 }
1131 
1132 const struct got_error *
1133 got_privsep_recv_index_progress(int *done, int *nobj_total,
1134     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
1135     struct imsgbuf *ibuf)
1136 {
1137 	const struct got_error *err = NULL;
1138 	struct imsg imsg;
1139 	struct got_imsg_index_pack_progress *iprogress;
1140 	size_t datalen;
1141 
1142 	*done = 0;
1143 	*nobj_total = 0;
1144 	*nobj_indexed = 0;
1145 	*nobj_resolved = 0;
1146 
1147 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1148 	if (err)
1149 		return err;
1150 
1151 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1152 	switch (imsg.hdr.type) {
1153 	case GOT_IMSG_ERROR:
1154 		if (datalen < sizeof(struct got_imsg_error)) {
1155 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1156 			break;
1157 		}
1158 		err = recv_imsg_error(&imsg, datalen);
1159 		break;
1160 	case GOT_IMSG_IDXPACK_PROGRESS:
1161 		if (datalen < sizeof(*iprogress)) {
1162 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1163 			break;
1164 		}
1165 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
1166 		*nobj_total = iprogress->nobj_total;
1167 		*nobj_indexed = iprogress->nobj_indexed;
1168 		*nobj_loose = iprogress->nobj_loose;
1169 		*nobj_resolved = iprogress->nobj_resolved;
1170 		break;
1171 	case GOT_IMSG_IDXPACK_DONE:
1172 		if (datalen != 0) {
1173 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1174 			break;
1175 		}
1176 		*done = 1;
1177 		break;
1178 	default:
1179 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1180 		break;
1181 	}
1182 
1183 	imsg_free(&imsg);
1184 	return err;
1185 }
1186 
1187 const struct got_error *
1188 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
1189     struct imsgbuf *ibuf)
1190 {
1191 	struct got_imsg_object *iobj;
1192 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1193 
1194 	if (datalen != sizeof(*iobj))
1195 		return got_error(GOT_ERR_PRIVSEP_LEN);
1196 	iobj = imsg->data;
1197 
1198 	*obj = calloc(1, sizeof(**obj));
1199 	if (*obj == NULL)
1200 		return got_error_from_errno("calloc");
1201 
1202 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
1203 	(*obj)->type = iobj->type;
1204 	(*obj)->flags = iobj->flags;
1205 	(*obj)->hdrlen = iobj->hdrlen;
1206 	(*obj)->size = iobj->size;
1207 	/* path_packfile is handled by caller */
1208 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
1209 		(*obj)->pack_offset = iobj->pack_offset;
1210 		(*obj)->pack_idx = iobj->pack_idx;
1211 	}
1212 	STAILQ_INIT(&(*obj)->deltas.entries);
1213 	return NULL;
1214 }
1215 
1216 const struct got_error *
1217 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
1218 {
1219 	const struct got_error *err = NULL;
1220 	struct imsg imsg;
1221 	const size_t min_datalen =
1222 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
1223 
1224 	*obj = NULL;
1225 
1226 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1227 	if (err)
1228 		return err;
1229 
1230 	switch (imsg.hdr.type) {
1231 	case GOT_IMSG_OBJECT:
1232 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
1233 		break;
1234 	default:
1235 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1236 		break;
1237 	}
1238 
1239 	imsg_free(&imsg);
1240 
1241 	return err;
1242 }
1243 
1244 static const struct got_error *
1245 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
1246     size_t logmsg_len)
1247 {
1248 	const struct got_error *err = NULL;
1249 	size_t offset, remain;
1250 
1251 	offset = 0;
1252 	remain = logmsg_len;
1253 	while (remain > 0) {
1254 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1255 
1256 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
1257 		    commit->logmsg + offset, n) == -1) {
1258 			err = got_error_from_errno("imsg_compose "
1259 			    "COMMIT_LOGMSG");
1260 			break;
1261 		}
1262 
1263 		err = flush_imsg(ibuf);
1264 		if (err)
1265 			break;
1266 
1267 		offset += n;
1268 		remain -= n;
1269 	}
1270 
1271 	return err;
1272 }
1273 
1274 const struct got_error *
1275 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
1276 {
1277 	const struct got_error *err = NULL;
1278 	struct got_imsg_commit_object *icommit;
1279 	uint8_t *buf;
1280 	size_t len, total;
1281 	struct got_object_qid *qid;
1282 	size_t author_len = strlen(commit->author);
1283 	size_t committer_len = strlen(commit->committer);
1284 	size_t logmsg_len = strlen(commit->logmsg);
1285 
1286 	total = sizeof(*icommit) + author_len + committer_len +
1287 	    commit->nparents * SHA1_DIGEST_LENGTH;
1288 
1289 	buf = malloc(total);
1290 	if (buf == NULL)
1291 		return got_error_from_errno("malloc");
1292 
1293 	icommit = (struct got_imsg_commit_object *)buf;
1294 	memcpy(icommit->tree_id, commit->tree_id->sha1,
1295 	    sizeof(icommit->tree_id));
1296 	icommit->author_len = author_len;
1297 	icommit->author_time = commit->author_time;
1298 	icommit->author_gmtoff = commit->author_gmtoff;
1299 	icommit->committer_len = committer_len;
1300 	icommit->committer_time = commit->committer_time;
1301 	icommit->committer_gmtoff = commit->committer_gmtoff;
1302 	icommit->logmsg_len = logmsg_len;
1303 	icommit->nparents = commit->nparents;
1304 
1305 	len = sizeof(*icommit);
1306 	memcpy(buf + len, commit->author, author_len);
1307 	len += author_len;
1308 	memcpy(buf + len, commit->committer, committer_len);
1309 	len += committer_len;
1310 	STAILQ_FOREACH(qid, &commit->parent_ids, entry) {
1311 		memcpy(buf + len, &qid->id, SHA1_DIGEST_LENGTH);
1312 		len += SHA1_DIGEST_LENGTH;
1313 	}
1314 
1315 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
1316 		err = got_error_from_errno("imsg_compose COMMIT");
1317 		goto done;
1318 	}
1319 
1320 	if (logmsg_len == 0 ||
1321 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1322 		err = flush_imsg(ibuf);
1323 		if (err)
1324 			goto done;
1325 	}
1326 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
1327 done:
1328 	free(buf);
1329 	return err;
1330 }
1331 
1332 static const struct got_error *
1333 get_commit_from_imsg(struct got_commit_object **commit,
1334     struct imsg *imsg, size_t datalen, struct imsgbuf *ibuf)
1335 {
1336 	const struct got_error *err = NULL;
1337 	struct got_imsg_commit_object *icommit;
1338 	size_t len = 0;
1339 	int i;
1340 
1341 	if (datalen < sizeof(*icommit))
1342 		return got_error(GOT_ERR_PRIVSEP_LEN);
1343 
1344 	icommit = imsg->data;
1345 	if (datalen != sizeof(*icommit) + icommit->author_len +
1346 	    icommit->committer_len +
1347 	    icommit->nparents * SHA1_DIGEST_LENGTH)
1348 		return got_error(GOT_ERR_PRIVSEP_LEN);
1349 
1350 	if (icommit->nparents < 0)
1351 		return got_error(GOT_ERR_PRIVSEP_LEN);
1352 
1353 	len += sizeof(*icommit);
1354 
1355 	*commit = got_object_commit_alloc_partial();
1356 	if (*commit == NULL)
1357 		return got_error_from_errno(
1358 		    "got_object_commit_alloc_partial");
1359 
1360 	memcpy((*commit)->tree_id->sha1, icommit->tree_id,
1361 	    SHA1_DIGEST_LENGTH);
1362 	(*commit)->author_time = icommit->author_time;
1363 	(*commit)->author_gmtoff = icommit->author_gmtoff;
1364 	(*commit)->committer_time = icommit->committer_time;
1365 	(*commit)->committer_gmtoff = icommit->committer_gmtoff;
1366 
1367 	if (icommit->author_len == 0) {
1368 		(*commit)->author = strdup("");
1369 		if ((*commit)->author == NULL) {
1370 			err = got_error_from_errno("strdup");
1371 			goto done;
1372 		}
1373 	} else {
1374 		(*commit)->author = malloc(icommit->author_len + 1);
1375 		if ((*commit)->author == NULL) {
1376 			err = got_error_from_errno("malloc");
1377 			goto done;
1378 		}
1379 		memcpy((*commit)->author, imsg->data + len,
1380 		    icommit->author_len);
1381 		(*commit)->author[icommit->author_len] = '\0';
1382 	}
1383 	len += icommit->author_len;
1384 
1385 	if (icommit->committer_len == 0) {
1386 		(*commit)->committer = strdup("");
1387 		if ((*commit)->committer == NULL) {
1388 			err = got_error_from_errno("strdup");
1389 			goto done;
1390 		}
1391 	} else {
1392 		(*commit)->committer =
1393 		    malloc(icommit->committer_len + 1);
1394 		if ((*commit)->committer == NULL) {
1395 			err = got_error_from_errno("malloc");
1396 			goto done;
1397 		}
1398 		memcpy((*commit)->committer, imsg->data + len,
1399 		    icommit->committer_len);
1400 		(*commit)->committer[icommit->committer_len] = '\0';
1401 	}
1402 	len += icommit->committer_len;
1403 
1404 	if (icommit->logmsg_len == 0) {
1405 		(*commit)->logmsg = strdup("");
1406 		if ((*commit)->logmsg == NULL) {
1407 			err = got_error_from_errno("strdup");
1408 			goto done;
1409 		}
1410 	} else {
1411 		size_t offset = 0, remain = icommit->logmsg_len;
1412 
1413 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1414 		if ((*commit)->logmsg == NULL) {
1415 			err = got_error_from_errno("malloc");
1416 			goto done;
1417 		}
1418 		while (remain > 0) {
1419 			struct imsg imsg_log;
1420 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1421 			    remain);
1422 
1423 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1424 			if (err)
1425 				goto done;
1426 
1427 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1428 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1429 				goto done;
1430 			}
1431 
1432 			memcpy((*commit)->logmsg + offset,
1433 			    imsg_log.data, n);
1434 			imsg_free(&imsg_log);
1435 			offset += n;
1436 			remain -= n;
1437 		}
1438 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1439 	}
1440 
1441 	for (i = 0; i < icommit->nparents; i++) {
1442 		struct got_object_qid *qid;
1443 
1444 		err = got_object_qid_alloc_partial(&qid);
1445 		if (err)
1446 			break;
1447 		memcpy(&qid->id, imsg->data + len +
1448 		    i * SHA1_DIGEST_LENGTH, sizeof(qid->id));
1449 		STAILQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1450 		(*commit)->nparents++;
1451 	}
1452 done:
1453 	if (err) {
1454 		got_object_commit_close(*commit);
1455 		*commit = NULL;
1456 	}
1457 	return err;
1458 }
1459 
1460 const struct got_error *
1461 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1462 {
1463 	const struct got_error *err = NULL;
1464 	struct imsg imsg;
1465 	size_t datalen;
1466 	const size_t min_datalen =
1467 	    MIN(sizeof(struct got_imsg_error),
1468 	    sizeof(struct got_imsg_commit_object));
1469 
1470 	*commit = NULL;
1471 
1472 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1473 	if (err)
1474 		return err;
1475 
1476 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1477 
1478 	switch (imsg.hdr.type) {
1479 	case GOT_IMSG_COMMIT:
1480 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1481 		break;
1482 	default:
1483 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1484 		break;
1485 	}
1486 
1487 	imsg_free(&imsg);
1488 
1489 	return err;
1490 }
1491 
1492 const struct got_error *
1493 got_privsep_send_tree(struct imsgbuf *ibuf,
1494     struct got_parsed_tree_entry *entries, int nentries)
1495 {
1496 	const struct got_error *err = NULL;
1497 	struct got_imsg_tree_object itree;
1498 	size_t totlen;
1499 	int i, nimsg; /* number of imsg queued in ibuf */
1500 
1501 	itree.nentries = nentries;
1502 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1503 	    == -1)
1504 		return got_error_from_errno("imsg_compose TREE");
1505 
1506 	totlen = sizeof(itree);
1507 	nimsg = 1;
1508 	for (i = 0; i < nentries; i++) {
1509 		struct got_parsed_tree_entry *pte = &entries[i];
1510 		struct ibuf *wbuf;
1511 		size_t len = sizeof(struct got_imsg_tree_entry) + pte->namelen;
1512 
1513 		if (len > MAX_IMSGSIZE)
1514 			return got_error(GOT_ERR_NO_SPACE);
1515 
1516 		nimsg++;
1517 		if (totlen + len >= MAX_IMSGSIZE - (IMSG_HEADER_SIZE * nimsg)) {
1518 			err = flush_imsg(ibuf);
1519 			if (err)
1520 				return err;
1521 			nimsg = 0;
1522 		}
1523 
1524 		wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRY, 0, 0, len);
1525 		if (wbuf == NULL)
1526 			return got_error_from_errno("imsg_create TREE_ENTRY");
1527 
1528 		/* Keep in sync with struct got_imsg_tree_object definition! */
1529 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1) {
1530 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1531 			ibuf_free(wbuf);
1532 			return err;
1533 		}
1534 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1) {
1535 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1536 			ibuf_free(wbuf);
1537 			return err;
1538 		}
1539 
1540 		if (imsg_add(wbuf, pte->name, pte->namelen) == -1) {
1541 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1542 			ibuf_free(wbuf);
1543 			return err;
1544 		}
1545 
1546 		wbuf->fd = -1;
1547 		imsg_close(ibuf, wbuf);
1548 
1549 		totlen += len;
1550 	}
1551 
1552 	return flush_imsg(ibuf);
1553 }
1554 
1555 const struct got_error *
1556 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1557 {
1558 	const struct got_error *err = NULL;
1559 	const size_t min_datalen =
1560 	    MIN(sizeof(struct got_imsg_error),
1561 	    sizeof(struct got_imsg_tree_object));
1562 	struct got_imsg_tree_object *itree;
1563 	int nentries = 0;
1564 
1565 	*tree = NULL;
1566 
1567 	err = read_imsg(ibuf);
1568 	if (err)
1569 		goto done;
1570 
1571 	for (;;) {
1572 		struct imsg imsg;
1573 		size_t n;
1574 		size_t datalen;
1575 		struct got_imsg_tree_entry *ite;
1576 		struct got_tree_entry *te = NULL;
1577 
1578 		n = imsg_get(ibuf, &imsg);
1579 		if (n == 0) {
1580 			if ((*tree)) {
1581 				if (nentries < (*tree)->nentries) {
1582 					err = read_imsg(ibuf);
1583 					if (err)
1584 						break;
1585 					continue;
1586 				} else
1587 					break;
1588 			} else {
1589 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1590 				break;
1591 			}
1592 		}
1593 
1594 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen) {
1595 			imsg_free(&imsg);
1596 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1597 			break;
1598 		}
1599 
1600 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1601 
1602 		switch (imsg.hdr.type) {
1603 		case GOT_IMSG_ERROR:
1604 			err = recv_imsg_error(&imsg, datalen);
1605 			break;
1606 		case GOT_IMSG_TREE:
1607 			/* This message should only appear once. */
1608 			if (*tree != NULL) {
1609 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1610 				break;
1611 			}
1612 			if (datalen != sizeof(*itree)) {
1613 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1614 				break;
1615 			}
1616 			itree = imsg.data;
1617 			if (itree->nentries < 0) {
1618 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1619 				break;
1620 			}
1621 			*tree = malloc(sizeof(**tree));
1622 			if (*tree == NULL) {
1623 				err = got_error_from_errno("malloc");
1624 				break;
1625 			}
1626 			(*tree)->entries = calloc(itree->nentries,
1627 			    sizeof(struct got_tree_entry));
1628 			if ((*tree)->entries == NULL) {
1629 				err = got_error_from_errno("malloc");
1630 				free(*tree);
1631 				*tree = NULL;
1632 				break;
1633 			}
1634 			(*tree)->nentries = itree->nentries;
1635 			(*tree)->refcnt = 0;
1636 			break;
1637 		case GOT_IMSG_TREE_ENTRY:
1638 			/* This message should be preceeded by GOT_IMSG_TREE. */
1639 			if (*tree == NULL) {
1640 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1641 				break;
1642 			}
1643 			if (datalen < sizeof(*ite) || datalen > MAX_IMSGSIZE) {
1644 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1645 				break;
1646 			}
1647 
1648 			/* Remaining data contains the entry's name. */
1649 			datalen -= sizeof(*ite);
1650 			if (datalen == 0 || datalen > MAX_IMSGSIZE) {
1651 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1652 				break;
1653 			}
1654 			ite = imsg.data;
1655 
1656 			if (datalen + 1 > sizeof(te->name)) {
1657 				err = got_error(GOT_ERR_NO_SPACE);
1658 				break;
1659 			}
1660 			if (nentries >= (*tree)->nentries) {
1661 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1662 				break;
1663 			}
1664 			te = &(*tree)->entries[nentries];
1665 			memcpy(te->name, imsg.data + sizeof(*ite), datalen);
1666 			te->name[datalen] = '\0';
1667 
1668 			memcpy(te->id.sha1, ite->id, SHA1_DIGEST_LENGTH);
1669 			te->mode = ite->mode;
1670 			te->idx = nentries;
1671 			nentries++;
1672 			break;
1673 		default:
1674 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1675 			break;
1676 		}
1677 
1678 		imsg_free(&imsg);
1679 		if (err)
1680 			break;
1681 	}
1682 done:
1683 	if (*tree && (*tree)->nentries != nentries) {
1684 		if (err == NULL)
1685 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1686 		got_object_tree_close(*tree);
1687 		*tree = NULL;
1688 	}
1689 
1690 	return err;
1691 }
1692 
1693 const struct got_error *
1694 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1695     const uint8_t *data)
1696 {
1697 	struct got_imsg_blob iblob;
1698 
1699 	iblob.size = size;
1700 	iblob.hdrlen = hdrlen;
1701 
1702 	if (data) {
1703 		uint8_t *buf;
1704 
1705 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1706 			return got_error(GOT_ERR_NO_SPACE);
1707 
1708 		buf = malloc(sizeof(iblob) + size);
1709 		if (buf == NULL)
1710 			return got_error_from_errno("malloc");
1711 
1712 		memcpy(buf, &iblob, sizeof(iblob));
1713 		memcpy(buf + sizeof(iblob), data, size);
1714 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1715 		    sizeof(iblob) + size) == -1) {
1716 			free(buf);
1717 			return got_error_from_errno("imsg_compose BLOB");
1718 		}
1719 		free(buf);
1720 	} else {
1721 		/* Data has already been written to file descriptor. */
1722 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1723 		    sizeof(iblob)) == -1)
1724 			return got_error_from_errno("imsg_compose BLOB");
1725 	}
1726 
1727 
1728 	return flush_imsg(ibuf);
1729 }
1730 
1731 const struct got_error *
1732 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1733     struct imsgbuf *ibuf)
1734 {
1735 	const struct got_error *err = NULL;
1736 	struct imsg imsg;
1737 	struct got_imsg_blob *iblob;
1738 	size_t datalen;
1739 
1740 	*outbuf = NULL;
1741 
1742 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1743 	if (err)
1744 		return err;
1745 
1746 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1747 
1748 	switch (imsg.hdr.type) {
1749 	case GOT_IMSG_BLOB:
1750 		if (datalen < sizeof(*iblob)) {
1751 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1752 			break;
1753 		}
1754 		iblob = imsg.data;
1755 		*size = iblob->size;
1756 		*hdrlen = iblob->hdrlen;
1757 
1758 		if (datalen == sizeof(*iblob)) {
1759 			/* Data has been written to file descriptor. */
1760 			break;
1761 		}
1762 
1763 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX) {
1764 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1765 			break;
1766 		}
1767 
1768 		*outbuf = malloc(*size);
1769 		if (*outbuf == NULL) {
1770 			err = got_error_from_errno("malloc");
1771 			break;
1772 		}
1773 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1774 		break;
1775 	default:
1776 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1777 		break;
1778 	}
1779 
1780 	imsg_free(&imsg);
1781 
1782 	return err;
1783 }
1784 
1785 static const struct got_error *
1786 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1787 {
1788 	const struct got_error *err = NULL;
1789 	size_t offset, remain;
1790 
1791 	offset = 0;
1792 	remain = tagmsg_len;
1793 	while (remain > 0) {
1794 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1795 
1796 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1797 		    tag->tagmsg + offset, n) == -1) {
1798 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1799 			break;
1800 		}
1801 
1802 		err = flush_imsg(ibuf);
1803 		if (err)
1804 			break;
1805 
1806 		offset += n;
1807 		remain -= n;
1808 	}
1809 
1810 	return err;
1811 }
1812 
1813 const struct got_error *
1814 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1815 {
1816 	const struct got_error *err = NULL;
1817 	struct got_imsg_tag_object *itag;
1818 	uint8_t *buf;
1819 	size_t len, total;
1820 	size_t tag_len = strlen(tag->tag);
1821 	size_t tagger_len = strlen(tag->tagger);
1822 	size_t tagmsg_len = strlen(tag->tagmsg);
1823 
1824 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1825 
1826 	buf = malloc(total);
1827 	if (buf == NULL)
1828 		return got_error_from_errno("malloc");
1829 
1830 	itag = (struct got_imsg_tag_object *)buf;
1831 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1832 	itag->obj_type = tag->obj_type;
1833 	itag->tag_len = tag_len;
1834 	itag->tagger_len = tagger_len;
1835 	itag->tagger_time = tag->tagger_time;
1836 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1837 	itag->tagmsg_len = tagmsg_len;
1838 
1839 	len = sizeof(*itag);
1840 	memcpy(buf + len, tag->tag, tag_len);
1841 	len += tag_len;
1842 	memcpy(buf + len, tag->tagger, tagger_len);
1843 	len += tagger_len;
1844 
1845 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1846 		err = got_error_from_errno("imsg_compose TAG");
1847 		goto done;
1848 	}
1849 
1850 	if (tagmsg_len == 0 ||
1851 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1852 		err = flush_imsg(ibuf);
1853 		if (err)
1854 			goto done;
1855 	}
1856 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1857 done:
1858 	free(buf);
1859 	return err;
1860 }
1861 
1862 const struct got_error *
1863 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1864 {
1865 	const struct got_error *err = NULL;
1866 	struct imsg imsg;
1867 	struct got_imsg_tag_object *itag;
1868 	size_t len, datalen;
1869 	const size_t min_datalen =
1870 	    MIN(sizeof(struct got_imsg_error),
1871 	    sizeof(struct got_imsg_tag_object));
1872 
1873 	*tag = NULL;
1874 
1875 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1876 	if (err)
1877 		return err;
1878 
1879 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1880 	len = 0;
1881 
1882 	switch (imsg.hdr.type) {
1883 	case GOT_IMSG_TAG:
1884 		if (datalen < sizeof(*itag)) {
1885 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1886 			break;
1887 		}
1888 		itag = imsg.data;
1889 		if (datalen != sizeof(*itag) + itag->tag_len +
1890 		    itag->tagger_len) {
1891 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1892 			break;
1893 		}
1894 		len += sizeof(*itag);
1895 
1896 		*tag = calloc(1, sizeof(**tag));
1897 		if (*tag == NULL) {
1898 			err = got_error_from_errno("calloc");
1899 			break;
1900 		}
1901 
1902 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1903 
1904 		if (itag->tag_len == 0) {
1905 			(*tag)->tag = strdup("");
1906 			if ((*tag)->tag == NULL) {
1907 				err = got_error_from_errno("strdup");
1908 				break;
1909 			}
1910 		} else {
1911 			(*tag)->tag = malloc(itag->tag_len + 1);
1912 			if ((*tag)->tag == NULL) {
1913 				err = got_error_from_errno("malloc");
1914 				break;
1915 			}
1916 			memcpy((*tag)->tag, imsg.data + len,
1917 			    itag->tag_len);
1918 			(*tag)->tag[itag->tag_len] = '\0';
1919 		}
1920 		len += itag->tag_len;
1921 
1922 		(*tag)->obj_type = itag->obj_type;
1923 		(*tag)->tagger_time = itag->tagger_time;
1924 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1925 
1926 		if (itag->tagger_len == 0) {
1927 			(*tag)->tagger = strdup("");
1928 			if ((*tag)->tagger == NULL) {
1929 				err = got_error_from_errno("strdup");
1930 				break;
1931 			}
1932 		} else {
1933 			(*tag)->tagger = malloc(itag->tagger_len + 1);
1934 			if ((*tag)->tagger == NULL) {
1935 				err = got_error_from_errno("malloc");
1936 				break;
1937 			}
1938 			memcpy((*tag)->tagger, imsg.data + len,
1939 			    itag->tagger_len);
1940 			(*tag)->tagger[itag->tagger_len] = '\0';
1941 		}
1942 		len += itag->tagger_len;
1943 
1944 		if (itag->tagmsg_len == 0) {
1945 			(*tag)->tagmsg = strdup("");
1946 			if ((*tag)->tagmsg == NULL) {
1947 				err = got_error_from_errno("strdup");
1948 				break;
1949 			}
1950 		} else {
1951 			size_t offset = 0, remain = itag->tagmsg_len;
1952 
1953 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1954 			if ((*tag)->tagmsg == NULL) {
1955 				err = got_error_from_errno("malloc");
1956 				break;
1957 			}
1958 			while (remain > 0) {
1959 				struct imsg imsg_log;
1960 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1961 				    remain);
1962 
1963 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1964 				if (err)
1965 					return err;
1966 
1967 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1968 					return got_error(GOT_ERR_PRIVSEP_MSG);
1969 
1970 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1971 				    n);
1972 				imsg_free(&imsg_log);
1973 				offset += n;
1974 				remain -= n;
1975 			}
1976 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1977 		}
1978 
1979 		break;
1980 	default:
1981 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1982 		break;
1983 	}
1984 
1985 	imsg_free(&imsg);
1986 
1987 	return err;
1988 }
1989 
1990 const struct got_error *
1991 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1992     struct got_packidx *packidx)
1993 {
1994 	const struct got_error *err = NULL;
1995 	struct got_imsg_packidx ipackidx;
1996 	struct got_imsg_pack ipack;
1997 	int fd;
1998 
1999 	ipackidx.len = packidx->len;
2000 	ipackidx.packfile_size = pack->filesize;
2001 	fd = dup(packidx->fd);
2002 	if (fd == -1)
2003 		return got_error_from_errno("dup");
2004 
2005 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
2006 	    sizeof(ipackidx)) == -1) {
2007 		err = got_error_from_errno("imsg_compose PACKIDX");
2008 		close(fd);
2009 		return err;
2010 	}
2011 
2012 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
2013 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
2014 		return got_error(GOT_ERR_NO_SPACE);
2015 	ipack.filesize = pack->filesize;
2016 
2017 	fd = dup(pack->fd);
2018 	if (fd == -1)
2019 		return got_error_from_errno("dup");
2020 
2021 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
2022 	    == -1) {
2023 		err = got_error_from_errno("imsg_compose PACK");
2024 		close(fd);
2025 		return err;
2026 	}
2027 
2028 	return flush_imsg(ibuf);
2029 }
2030 
2031 const struct got_error *
2032 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
2033     struct got_object_id *id)
2034 {
2035 	struct got_imsg_packed_object iobj;
2036 
2037 	iobj.idx = idx;
2038 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2039 
2040 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
2041 	    &iobj, sizeof(iobj)) == -1)
2042 		return got_error_from_errno("imsg_compose "
2043 		    "PACKED_OBJECT_REQUEST");
2044 
2045 	return flush_imsg(ibuf);
2046 }
2047 
2048 const struct got_error *
2049 got_privsep_send_packed_raw_obj_req(struct imsgbuf *ibuf, int idx,
2050     struct got_object_id *id)
2051 {
2052 	struct got_imsg_packed_object iobj;
2053 
2054 	iobj.idx = idx;
2055 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2056 
2057 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_RAW_OBJECT_REQUEST, 0, 0, -1,
2058 	    &iobj, sizeof(iobj)) == -1)
2059 		return got_error_from_errno("imsg_compose "
2060 		    "PACKED_OBJECT_REQUEST");
2061 
2062 	return flush_imsg(ibuf);
2063 }
2064 
2065 const struct got_error *
2066 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
2067 {
2068 	const struct got_error *err = NULL;
2069 
2070 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
2071 	    NULL, 0) == -1) {
2072 		err = got_error_from_errno("imsg_compose "
2073 		    "GITCONFIG_PARSE_REQUEST");
2074 		close(fd);
2075 		return err;
2076 	}
2077 
2078 	return flush_imsg(ibuf);
2079 }
2080 
2081 const struct got_error *
2082 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
2083 {
2084 	if (imsg_compose(ibuf,
2085 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
2086 	    NULL, 0) == -1)
2087 		return got_error_from_errno("imsg_compose "
2088 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
2089 
2090 	return flush_imsg(ibuf);
2091 }
2092 
2093 const struct got_error *
2094 got_privsep_send_gitconfig_repository_extensions_req(struct imsgbuf *ibuf)
2095 {
2096 	if (imsg_compose(ibuf,
2097 	    GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST, 0, 0, -1,
2098 	    NULL, 0) == -1)
2099 		return got_error_from_errno("imsg_compose "
2100 		    "GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST");
2101 
2102 	return flush_imsg(ibuf);
2103 }
2104 
2105 
2106 const struct got_error *
2107 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
2108 {
2109 	if (imsg_compose(ibuf,
2110 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
2111 		return got_error_from_errno("imsg_compose "
2112 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
2113 
2114 	return flush_imsg(ibuf);
2115 }
2116 
2117 const struct got_error *
2118 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
2119 {
2120 	if (imsg_compose(ibuf,
2121 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
2122 		return got_error_from_errno("imsg_compose "
2123 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
2124 
2125 	return flush_imsg(ibuf);
2126 }
2127 
2128 const struct got_error *
2129 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
2130 {
2131 	if (imsg_compose(ibuf,
2132 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2133 		return got_error_from_errno("imsg_compose "
2134 		    "GITCONFIG_REMOTE_REQUEST");
2135 
2136 	return flush_imsg(ibuf);
2137 }
2138 
2139 const struct got_error *
2140 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
2141 {
2142 	if (imsg_compose(ibuf,
2143 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
2144 		return got_error_from_errno("imsg_compose "
2145 		    "GITCONFIG_OWNER_REQUEST");
2146 
2147 	return flush_imsg(ibuf);
2148 }
2149 
2150 const struct got_error *
2151 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
2152 {
2153 	const struct got_error *err = NULL;
2154 	struct imsg imsg;
2155 	size_t datalen;
2156 	const size_t min_datalen = 0;
2157 
2158 	*str = NULL;
2159 
2160 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2161 	if (err)
2162 		return err;
2163 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2164 
2165 	switch (imsg.hdr.type) {
2166 	case GOT_IMSG_GITCONFIG_STR_VAL:
2167 		if (datalen == 0)
2168 			break;
2169 		/* datalen does not include terminating \0 */
2170 		*str = malloc(datalen + 1);
2171 		if (*str == NULL) {
2172 			err = got_error_from_errno("malloc");
2173 			break;
2174 		}
2175 		memcpy(*str, imsg.data, datalen);
2176 		(*str)[datalen] = '\0';
2177 		break;
2178 	default:
2179 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2180 		break;
2181 	}
2182 
2183 	imsg_free(&imsg);
2184 	return err;
2185 }
2186 
2187 const struct got_error *
2188 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
2189 {
2190 	const struct got_error *err = NULL;
2191 	struct imsg imsg;
2192 	size_t datalen;
2193 	const size_t min_datalen =
2194 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
2195 
2196 	*val = 0;
2197 
2198 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2199 	if (err)
2200 		return err;
2201 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2202 
2203 	switch (imsg.hdr.type) {
2204 	case GOT_IMSG_GITCONFIG_INT_VAL:
2205 		if (datalen != sizeof(*val)) {
2206 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2207 			break;
2208 		}
2209 		memcpy(val, imsg.data, sizeof(*val));
2210 		break;
2211 	default:
2212 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2213 		break;
2214 	}
2215 
2216 	imsg_free(&imsg);
2217 	return err;
2218 }
2219 
2220 static void
2221 free_remote_data(struct got_remote_repo *remote)
2222 {
2223 	int i;
2224 
2225 	free(remote->name);
2226 	free(remote->fetch_url);
2227 	free(remote->send_url);
2228 	for (i = 0; i < remote->nfetch_branches; i++)
2229 		free(remote->fetch_branches[i]);
2230 	free(remote->fetch_branches);
2231 	for (i = 0; i < remote->nsend_branches; i++)
2232 		free(remote->send_branches[i]);
2233 	free(remote->send_branches);
2234 	for (i = 0; i < remote->nfetch_refs; i++)
2235 		free(remote->fetch_refs[i]);
2236 	free(remote->fetch_refs);
2237 }
2238 
2239 const struct got_error *
2240 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
2241     int *nremotes, struct imsgbuf *ibuf)
2242 {
2243 	const struct got_error *err = NULL;
2244 	struct imsg imsg;
2245 	size_t datalen;
2246 	struct got_imsg_remotes iremotes;
2247 	struct got_imsg_remote iremote;
2248 
2249 	*remotes = NULL;
2250 	*nremotes = 0;
2251 	iremotes.nremotes = 0;
2252 
2253 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
2254 	if (err)
2255 		return err;
2256 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2257 
2258 	switch (imsg.hdr.type) {
2259 	case GOT_IMSG_GITCONFIG_REMOTES:
2260 		if (datalen != sizeof(iremotes)) {
2261 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2262 			break;
2263 		}
2264 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2265 		if (iremotes.nremotes == 0) {
2266 			imsg_free(&imsg);
2267 			return NULL;
2268 		}
2269 		break;
2270 	default:
2271 		imsg_free(&imsg);
2272 		return got_error(GOT_ERR_PRIVSEP_MSG);
2273 	}
2274 
2275 	imsg_free(&imsg);
2276 
2277 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2278 	if (*remotes == NULL)
2279 		return got_error_from_errno("recallocarray");
2280 
2281 	while (*nremotes < iremotes.nremotes) {
2282 		struct got_remote_repo *remote;
2283 
2284 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
2285 		if (err)
2286 			break;
2287 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2288 
2289 		switch (imsg.hdr.type) {
2290 		case GOT_IMSG_GITCONFIG_REMOTE:
2291 			remote = &(*remotes)[*nremotes];
2292 			memset(remote, 0, sizeof(*remote));
2293 			if (datalen < sizeof(iremote)) {
2294 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2295 				break;
2296 			}
2297 			memcpy(&iremote, imsg.data, sizeof(iremote));
2298 			if (iremote.name_len == 0 ||
2299 			    iremote.fetch_url_len == 0 ||
2300 			    iremote.send_url_len == 0 ||
2301 			    (sizeof(iremote) + iremote.name_len +
2302 			    iremote.fetch_url_len + iremote.send_url_len) > datalen) {
2303 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2304 				break;
2305 			}
2306 			remote->name = strndup(imsg.data + sizeof(iremote),
2307 			    iremote.name_len);
2308 			if (remote->name == NULL) {
2309 				err = got_error_from_errno("strndup");
2310 				break;
2311 			}
2312 			remote->fetch_url = strndup(imsg.data + sizeof(iremote) +
2313 			    iremote.name_len, iremote.fetch_url_len);
2314 			if (remote->fetch_url == NULL) {
2315 				err = got_error_from_errno("strndup");
2316 				free_remote_data(remote);
2317 				break;
2318 			}
2319 			remote->send_url = strndup(imsg.data + sizeof(iremote) +
2320 			    iremote.name_len + iremote.fetch_url_len,
2321 			    iremote.send_url_len);
2322 			if (remote->send_url == NULL) {
2323 				err = got_error_from_errno("strndup");
2324 				free_remote_data(remote);
2325 				break;
2326 			}
2327 			remote->mirror_references = iremote.mirror_references;
2328 			remote->fetch_all_branches = iremote.fetch_all_branches;
2329 			remote->nfetch_branches = 0;
2330 			remote->fetch_branches = NULL;
2331 			remote->nsend_branches = 0;
2332 			remote->send_branches = NULL;
2333 			remote->nfetch_refs = 0;
2334 			remote->fetch_refs = NULL;
2335 			(*nremotes)++;
2336 			break;
2337 		default:
2338 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2339 			break;
2340 		}
2341 
2342 		imsg_free(&imsg);
2343 		if (err)
2344 			break;
2345 	}
2346 
2347 	if (err) {
2348 		int i;
2349 		for (i = 0; i < *nremotes; i++)
2350 			free_remote_data(&(*remotes)[i]);
2351 		free(*remotes);
2352 		*remotes = NULL;
2353 		*nremotes = 0;
2354 	}
2355 	return err;
2356 }
2357 
2358 const struct got_error *
2359 got_privsep_send_gotconfig_parse_req(struct imsgbuf *ibuf, int fd)
2360 {
2361 	const struct got_error *err = NULL;
2362 
2363 	if (imsg_compose(ibuf, GOT_IMSG_GOTCONFIG_PARSE_REQUEST, 0, 0, fd,
2364 	    NULL, 0) == -1) {
2365 		err = got_error_from_errno("imsg_compose "
2366 		    "GOTCONFIG_PARSE_REQUEST");
2367 		close(fd);
2368 		return err;
2369 	}
2370 
2371 	return flush_imsg(ibuf);
2372 }
2373 
2374 const struct got_error *
2375 got_privsep_send_gotconfig_author_req(struct imsgbuf *ibuf)
2376 {
2377 	if (imsg_compose(ibuf,
2378 	    GOT_IMSG_GOTCONFIG_AUTHOR_REQUEST, 0, 0, -1, NULL, 0) == -1)
2379 		return got_error_from_errno("imsg_compose "
2380 		    "GOTCONFIG_AUTHOR_REQUEST");
2381 
2382 	return flush_imsg(ibuf);
2383 }
2384 
2385 const struct got_error *
2386 got_privsep_send_gotconfig_remotes_req(struct imsgbuf *ibuf)
2387 {
2388 	if (imsg_compose(ibuf,
2389 	    GOT_IMSG_GOTCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2390 		return got_error_from_errno("imsg_compose "
2391 		    "GOTCONFIG_REMOTE_REQUEST");
2392 
2393 	return flush_imsg(ibuf);
2394 }
2395 
2396 const struct got_error *
2397 got_privsep_recv_gotconfig_str(char **str, struct imsgbuf *ibuf)
2398 {
2399 	const struct got_error *err = NULL;
2400 	struct imsg imsg;
2401 	size_t datalen;
2402 	const size_t min_datalen = 0;
2403 
2404 	*str = NULL;
2405 
2406 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2407 	if (err)
2408 		return err;
2409 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2410 
2411 	switch (imsg.hdr.type) {
2412 	case GOT_IMSG_ERROR:
2413 		if (datalen < sizeof(struct got_imsg_error)) {
2414 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2415 			break;
2416 		}
2417 		err = recv_imsg_error(&imsg, datalen);
2418 		break;
2419 	case GOT_IMSG_GOTCONFIG_STR_VAL:
2420 		if (datalen == 0)
2421 			break;
2422 		/* datalen does not include terminating \0 */
2423 		*str = malloc(datalen + 1);
2424 		if (*str == NULL) {
2425 			err = got_error_from_errno("malloc");
2426 			break;
2427 		}
2428 		memcpy(*str, imsg.data, datalen);
2429 		(*str)[datalen] = '\0';
2430 		break;
2431 	default:
2432 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2433 		break;
2434 	}
2435 
2436 	imsg_free(&imsg);
2437 	return err;
2438 }
2439 
2440 const struct got_error *
2441 got_privsep_recv_gotconfig_remotes(struct got_remote_repo **remotes,
2442     int *nremotes, struct imsgbuf *ibuf)
2443 {
2444 	const struct got_error *err = NULL;
2445 	struct imsg imsg;
2446 	size_t datalen;
2447 	struct got_imsg_remotes iremotes;
2448 	struct got_imsg_remote iremote;
2449 	const size_t min_datalen =
2450 	    MIN(sizeof(struct got_imsg_error), sizeof(iremotes));
2451 
2452 	*remotes = NULL;
2453 	*nremotes = 0;
2454 	iremotes.nremotes = 0;
2455 
2456 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2457 	if (err)
2458 		return err;
2459 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2460 
2461 	switch (imsg.hdr.type) {
2462 	case GOT_IMSG_ERROR:
2463 		if (datalen < sizeof(struct got_imsg_error)) {
2464 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2465 			break;
2466 		}
2467 		err = recv_imsg_error(&imsg, datalen);
2468 		break;
2469 	case GOT_IMSG_GOTCONFIG_REMOTES:
2470 		if (datalen != sizeof(iremotes)) {
2471 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2472 			break;
2473 		}
2474 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2475 		if (iremotes.nremotes == 0) {
2476 			imsg_free(&imsg);
2477 			return NULL;
2478 		}
2479 		break;
2480 	default:
2481 		imsg_free(&imsg);
2482 		return got_error(GOT_ERR_PRIVSEP_MSG);
2483 	}
2484 
2485 	imsg_free(&imsg);
2486 
2487 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2488 	if (*remotes == NULL)
2489 		return got_error_from_errno("recallocarray");
2490 
2491 	while (*nremotes < iremotes.nremotes) {
2492 		struct got_remote_repo *remote;
2493 		const size_t min_datalen =
2494 		    MIN(sizeof(struct got_imsg_error), sizeof(iremote));
2495 		int i;
2496 
2497 		err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2498 		if (err)
2499 			break;
2500 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2501 
2502 		switch (imsg.hdr.type) {
2503 		case GOT_IMSG_ERROR:
2504 			if (datalen < sizeof(struct got_imsg_error)) {
2505 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2506 				break;
2507 			}
2508 			err = recv_imsg_error(&imsg, datalen);
2509 			break;
2510 		case GOT_IMSG_GOTCONFIG_REMOTE:
2511 			remote = &(*remotes)[*nremotes];
2512 			memset(remote, 0, sizeof(*remote));
2513 			if (datalen < sizeof(iremote)) {
2514 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2515 				break;
2516 			}
2517 			memcpy(&iremote, imsg.data, sizeof(iremote));
2518 			if (iremote.name_len == 0 ||
2519 			    (iremote.fetch_url_len == 0 &&
2520 			    iremote.send_url_len == 0) ||
2521 			    (sizeof(iremote) + iremote.name_len +
2522 			    iremote.fetch_url_len + iremote.send_url_len) >
2523 			    datalen) {
2524 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2525 				break;
2526 			}
2527 			remote->name = strndup(imsg.data + sizeof(iremote),
2528 			    iremote.name_len);
2529 			if (remote->name == NULL) {
2530 				err = got_error_from_errno("strndup");
2531 				break;
2532 			}
2533 			remote->fetch_url = strndup(imsg.data +
2534 			    sizeof(iremote) + iremote.name_len,
2535 			    iremote.fetch_url_len);
2536 			if (remote->fetch_url == NULL) {
2537 				err = got_error_from_errno("strndup");
2538 				free_remote_data(remote);
2539 				break;
2540 			}
2541 			remote->send_url = strndup(imsg.data +
2542 			    sizeof(iremote) + iremote.name_len +
2543 			    iremote.fetch_url_len, iremote.send_url_len);
2544 			if (remote->send_url == NULL) {
2545 				err = got_error_from_errno("strndup");
2546 				free_remote_data(remote);
2547 				break;
2548 			}
2549 			remote->mirror_references = iremote.mirror_references;
2550 			remote->fetch_all_branches = iremote.fetch_all_branches;
2551 			if (iremote.nfetch_branches > 0) {
2552 				remote->fetch_branches = recallocarray(NULL, 0,
2553 				    iremote.nfetch_branches, sizeof(char *));
2554 				if (remote->fetch_branches == NULL) {
2555 					err = got_error_from_errno("calloc");
2556 					free_remote_data(remote);
2557 					break;
2558 				}
2559 			}
2560 			remote->nfetch_branches = 0;
2561 			for (i = 0; i < iremote.nfetch_branches; i++) {
2562 				char *branch;
2563 				err = got_privsep_recv_gotconfig_str(&branch,
2564 				    ibuf);
2565 				if (err) {
2566 					free_remote_data(remote);
2567 					goto done;
2568 				}
2569 				remote->fetch_branches[i] = branch;
2570 				remote->nfetch_branches++;
2571 			}
2572 			if (iremote.nsend_branches > 0) {
2573 				remote->send_branches = recallocarray(NULL, 0,
2574 				    iremote.nsend_branches, sizeof(char *));
2575 				if (remote->send_branches == NULL) {
2576 					err = got_error_from_errno("calloc");
2577 					free_remote_data(remote);
2578 					break;
2579 				}
2580 			}
2581 			remote->nsend_branches = 0;
2582 			for (i = 0; i < iremote.nsend_branches; i++) {
2583 				char *branch;
2584 				err = got_privsep_recv_gotconfig_str(&branch,
2585 				    ibuf);
2586 				if (err) {
2587 					free_remote_data(remote);
2588 					goto done;
2589 				}
2590 				remote->send_branches[i] = branch;
2591 				remote->nsend_branches++;
2592 			}
2593 			if (iremote.nfetch_refs > 0) {
2594 				remote->fetch_refs = recallocarray(NULL, 0,
2595 				    iremote.nfetch_refs, sizeof(char *));
2596 				if (remote->fetch_refs == NULL) {
2597 					err = got_error_from_errno("calloc");
2598 					free_remote_data(remote);
2599 					break;
2600 				}
2601 			}
2602 			remote->nfetch_refs = 0;
2603 			for (i = 0; i < iremote.nfetch_refs; i++) {
2604 				char *ref;
2605 				err = got_privsep_recv_gotconfig_str(&ref,
2606 				    ibuf);
2607 				if (err) {
2608 					free_remote_data(remote);
2609 					goto done;
2610 				}
2611 				remote->fetch_refs[i] = ref;
2612 				remote->nfetch_refs++;
2613 			}
2614 			(*nremotes)++;
2615 			break;
2616 		default:
2617 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2618 			break;
2619 		}
2620 
2621 		imsg_free(&imsg);
2622 		if (err)
2623 			break;
2624 	}
2625 done:
2626 	if (err) {
2627 		int i;
2628 		for (i = 0; i < *nremotes; i++)
2629 			free_remote_data(&(*remotes)[i]);
2630 		free(*remotes);
2631 		*remotes = NULL;
2632 		*nremotes = 0;
2633 	}
2634 	return err;
2635 }
2636 
2637 const struct got_error *
2638 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
2639     struct got_object_id *id, int idx, const char *path)
2640 {
2641 	const struct got_error *err = NULL;
2642 	struct ibuf *wbuf;
2643 	size_t path_len = strlen(path) + 1;
2644 
2645 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
2646 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
2647 	if (wbuf == NULL)
2648 		return got_error_from_errno(
2649 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
2650 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
2651 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2652 		ibuf_free(wbuf);
2653 		return err;
2654 	}
2655 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1) {
2656 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2657 		ibuf_free(wbuf);
2658 		return err;
2659 	}
2660 	if (imsg_add(wbuf, path, path_len) == -1) {
2661 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2662 		ibuf_free(wbuf);
2663 		return err;
2664 	}
2665 
2666 	wbuf->fd = -1;
2667 	imsg_close(ibuf, wbuf);
2668 
2669 	return flush_imsg(ibuf);
2670 }
2671 
2672 const struct got_error *
2673 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
2674     struct got_object_id **changed_commit_id,
2675     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
2676 {
2677 	const struct got_error *err = NULL;
2678 	struct imsg imsg;
2679 	struct got_imsg_traversed_commits *icommits;
2680 	size_t datalen;
2681 	int i, done = 0;
2682 
2683 	*changed_commit = NULL;
2684 	*changed_commit_id = NULL;
2685 
2686 	while (!done) {
2687 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2688 		if (err)
2689 			return err;
2690 
2691 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2692 		switch (imsg.hdr.type) {
2693 		case GOT_IMSG_TRAVERSED_COMMITS:
2694 			icommits = imsg.data;
2695 			if (datalen != sizeof(*icommits) +
2696 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
2697 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2698 				break;
2699 			}
2700 			for (i = 0; i < icommits->ncommits; i++) {
2701 				struct got_object_qid *qid;
2702 				uint8_t *sha1 = (uint8_t *)imsg.data +
2703 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
2704 				err = got_object_qid_alloc_partial(&qid);
2705 				if (err)
2706 					break;
2707 				memcpy(qid->id.sha1, sha1, SHA1_DIGEST_LENGTH);
2708 				STAILQ_INSERT_TAIL(commit_ids, qid, entry);
2709 
2710 				/* The last commit may contain a change. */
2711 				if (i == icommits->ncommits - 1) {
2712 					*changed_commit_id =
2713 					    got_object_id_dup(&qid->id);
2714 					if (*changed_commit_id == NULL) {
2715 						err = got_error_from_errno(
2716 						    "got_object_id_dup");
2717 						break;
2718 					}
2719 				}
2720 			}
2721 			break;
2722 		case GOT_IMSG_COMMIT:
2723 			if (*changed_commit_id == NULL) {
2724 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2725 				break;
2726 			}
2727 			err = get_commit_from_imsg(changed_commit, &imsg,
2728 			    datalen, ibuf);
2729 			break;
2730 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
2731 			done = 1;
2732 			break;
2733 		default:
2734 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2735 			break;
2736 		}
2737 
2738 		imsg_free(&imsg);
2739 		if (err)
2740 			break;
2741 	}
2742 
2743 	if (err)
2744 		got_object_id_queue_free(commit_ids);
2745 	return err;
2746 }
2747 
2748 const struct got_error *
2749 got_privsep_send_raw_delta_req(struct imsgbuf *ibuf, int idx,
2750     struct got_object_id *id)
2751 {
2752 	struct got_imsg_raw_delta_request dreq;
2753 
2754 	dreq.idx = idx;
2755 	memcpy(dreq.id, id->sha1, SHA1_DIGEST_LENGTH);
2756 
2757 	if (imsg_compose(ibuf, GOT_IMSG_RAW_DELTA_REQUEST, 0, 0, -1,
2758 	    &dreq, sizeof(dreq)) == -1)
2759 		return got_error_from_errno("imsg_compose RAW_DELTA_REQUEST");
2760 
2761 	return flush_imsg(ibuf);
2762 }
2763 
2764 const struct got_error *
2765 got_privsep_send_raw_delta_outfd(struct imsgbuf *ibuf, int fd)
2766 {
2767 	return send_fd(ibuf, GOT_IMSG_RAW_DELTA_OUTFD, fd);
2768 }
2769 
2770 const struct got_error *
2771 got_privsep_send_raw_delta(struct imsgbuf *ibuf, uint64_t base_size,
2772     uint64_t result_size,  off_t delta_size, off_t delta_compressed_size,
2773     off_t delta_offset, off_t delta_out_offset, struct got_object_id *base_id)
2774 {
2775 	struct got_imsg_raw_delta idelta;
2776 	int ret;
2777 
2778 	idelta.base_size = base_size;
2779 	idelta.result_size = result_size;
2780 	idelta.delta_size = delta_size;
2781 	idelta.delta_compressed_size = delta_compressed_size;
2782 	idelta.delta_offset = delta_offset;
2783 	idelta.delta_out_offset = delta_out_offset;
2784 	memcpy(idelta.base_id, base_id->sha1, SHA1_DIGEST_LENGTH);
2785 
2786 	ret = imsg_compose(ibuf, GOT_IMSG_RAW_DELTA, 0, 0, -1,
2787 	    &idelta, sizeof(idelta));
2788 	if (ret == -1)
2789 		return got_error_from_errno("imsg_compose RAW_DELTA");
2790 
2791 	return flush_imsg(ibuf);
2792 }
2793 
2794 const struct got_error *
2795 got_privsep_recv_raw_delta(uint64_t *base_size, uint64_t *result_size,
2796     off_t *delta_size, off_t *delta_compressed_size, off_t *delta_offset,
2797     off_t *delta_out_offset, struct got_object_id **base_id, struct imsgbuf *ibuf)
2798 {
2799 	const struct got_error *err = NULL;
2800 	struct imsg imsg;
2801 	struct got_imsg_raw_delta *delta;
2802 	size_t datalen;
2803 
2804 	*base_size = 0;
2805 	*result_size = 0;
2806 	*delta_size = 0;
2807 	*delta_compressed_size = 0;
2808 	*delta_offset = 0;
2809 	*delta_out_offset = 0;
2810 	*base_id = NULL;
2811 
2812 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2813 	if (err)
2814 		return err;
2815 
2816 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2817 
2818 	switch (imsg.hdr.type) {
2819 	case GOT_IMSG_RAW_DELTA:
2820 		if (datalen != sizeof(*delta)) {
2821 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2822 			break;
2823 		}
2824 		delta = imsg.data;
2825 		*base_size = delta->base_size;
2826 		*result_size = delta->result_size;
2827 		*delta_size = delta->delta_size;
2828 		*delta_compressed_size = delta->delta_compressed_size;
2829 		*delta_offset = delta->delta_offset;
2830 		*delta_out_offset = delta->delta_out_offset;
2831 		*base_id = calloc(1, sizeof(**base_id));
2832 		if (*base_id == NULL) {
2833 			err = got_error_from_errno("malloc");
2834 			break;
2835 		}
2836 		memcpy((*base_id)->sha1, delta->base_id, SHA1_DIGEST_LENGTH);
2837 		break;
2838 	default:
2839 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2840 		break;
2841 	}
2842 
2843 	imsg_free(&imsg);
2844 
2845 	if (err) {
2846 		free(*base_id);
2847 		*base_id = NULL;
2848 	}
2849 	return err;
2850 }
2851 
2852 const struct got_error *
2853 got_privsep_send_object_idlist(struct imsgbuf *ibuf,
2854     struct got_object_id **ids, size_t nids)
2855 {
2856 	const struct got_error *err = NULL;
2857 	struct got_imsg_object_idlist idlist;
2858 	struct ibuf *wbuf;
2859 	size_t i;
2860 
2861 	if (nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS)
2862 		return got_error(GOT_ERR_NO_SPACE);
2863 
2864 	wbuf = imsg_create(ibuf, GOT_IMSG_OBJ_ID_LIST, 0, 0,
2865 	    sizeof(idlist) + nids * sizeof(**ids));
2866 	if (wbuf == NULL) {
2867 		err = got_error_from_errno("imsg_create OBJ_ID_LIST");
2868 		return err;
2869 	}
2870 
2871 	idlist.nids = nids;
2872 	if (imsg_add(wbuf, &idlist, sizeof(idlist)) == -1) {
2873 		err = got_error_from_errno("imsg_add OBJ_ID_LIST");
2874 		ibuf_free(wbuf);
2875 		return err;
2876 	}
2877 
2878 	for (i = 0; i < nids; i++) {
2879 		struct got_object_id *id = ids[i];
2880 		if (imsg_add(wbuf, id, sizeof(*id)) == -1) {
2881 			err = got_error_from_errno("imsg_add OBJ_ID_LIST");
2882 			ibuf_free(wbuf);
2883 			return err;
2884 		}
2885 	}
2886 	
2887 	wbuf->fd = -1;
2888 	imsg_close(ibuf, wbuf);
2889 
2890 	return flush_imsg(ibuf);
2891 }
2892 
2893 const struct got_error *
2894 got_privsep_send_object_idlist_done(struct imsgbuf *ibuf)
2895 {
2896 	if (imsg_compose(ibuf, GOT_IMSG_OBJ_ID_LIST_DONE, 0, 0, -1, NULL, 0)
2897 	    == -1)
2898 		return got_error_from_errno("imsg_compose OBJ_ID_LIST_DONE");
2899 
2900 	return flush_imsg(ibuf);
2901 }
2902 
2903 const struct got_error *
2904 got_privsep_recv_object_idlist(int *done, struct got_object_id **ids,
2905     size_t *nids, struct imsgbuf *ibuf)
2906 {
2907 	const struct got_error *err = NULL;
2908 	struct imsg imsg;
2909 	struct got_imsg_object_idlist *idlist;
2910 	size_t datalen;
2911 
2912 	*ids = NULL;
2913 	*done = 0;
2914 	*nids = 0;
2915 
2916 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2917 	if (err)
2918 		return err;
2919 
2920 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2921 	switch (imsg.hdr.type) {
2922 	case GOT_IMSG_OBJ_ID_LIST:
2923 		if (datalen < sizeof(*idlist)) {
2924 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2925 			break;
2926 		}
2927 		idlist = imsg.data;
2928 		if (idlist->nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS) {
2929 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2930 			break;
2931 		}
2932 		*nids = idlist->nids;
2933 		*ids = calloc(*nids, sizeof(**ids));
2934 		if (*ids == NULL) {
2935 			err = got_error_from_errno("calloc");
2936 			break;
2937 		}
2938 		memcpy(*ids, (uint8_t *)imsg.data + sizeof(idlist),
2939 		    *nids * sizeof(**ids));
2940 		break;
2941 	case GOT_IMSG_OBJ_ID_LIST_DONE:
2942 		*done = 1;
2943 		break;
2944 	default:
2945 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2946 		break;
2947 	}
2948 
2949 	imsg_free(&imsg);
2950 
2951 	return err;
2952 }
2953 
2954 const struct got_error *
2955 got_privsep_send_delta_reuse_req(struct imsgbuf *ibuf)
2956 {
2957 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_REQUEST, 0, 0, -1, NULL, 0)
2958 	    == -1)
2959 		return got_error_from_errno("imsg_compose DELTA_REUSE_REQUEST");
2960 
2961 	return flush_imsg(ibuf);
2962 }
2963 
2964 const struct got_error *
2965 got_privsep_send_reused_deltas(struct imsgbuf *ibuf,
2966     struct got_imsg_reused_delta *deltas, size_t ndeltas)
2967 {
2968 	const struct got_error *err = NULL;
2969 	struct ibuf *wbuf;
2970 	struct got_imsg_reused_deltas ideltas;
2971 	size_t i;
2972 
2973 	if (ndeltas > GOT_IMSG_REUSED_DELTAS_MAX_NDELTAS)
2974 		return got_error(GOT_ERR_NO_SPACE);
2975 
2976 	wbuf = imsg_create(ibuf, GOT_IMSG_REUSED_DELTAS, 0, 0,
2977 	    sizeof(ideltas) + ndeltas * sizeof(*deltas));
2978 	if (wbuf == NULL) {
2979 		err = got_error_from_errno("imsg_create REUSED_DELTAS");
2980 		return err;
2981 	}
2982 
2983 	ideltas.ndeltas = ndeltas;
2984 	if (imsg_add(wbuf, &ideltas, sizeof(ideltas)) == -1) {
2985 		err = got_error_from_errno("imsg_add REUSED_DELTAS");
2986 		ibuf_free(wbuf);
2987 		return err;
2988 	}
2989 
2990 	for (i = 0; i < ndeltas; i++) {
2991 		struct got_imsg_reused_delta *delta = &deltas[i];
2992 		if (imsg_add(wbuf, delta, sizeof(*delta)) == -1) {
2993 			err = got_error_from_errno("imsg_add REUSED_DELTAS");
2994 			ibuf_free(wbuf);
2995 			return err;
2996 		}
2997 	}
2998 	
2999 	wbuf->fd = -1;
3000 	imsg_close(ibuf, wbuf);
3001 
3002 	return flush_imsg(ibuf);
3003 }
3004 
3005 const struct got_error *
3006 got_privsep_send_reused_deltas_done(struct imsgbuf *ibuf)
3007 {
3008 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_DONE, 0, 0, -1, NULL, 0)
3009 	    == -1)
3010 		return got_error_from_errno("imsg_compose DELTA_REUSE_DONE");
3011 
3012 	return flush_imsg(ibuf);
3013 }
3014 
3015 const struct got_error *
3016 got_privsep_recv_reused_deltas(int *done, struct got_imsg_reused_delta *deltas,
3017     size_t *ndeltas, struct imsgbuf *ibuf)
3018 {
3019 	const struct got_error *err = NULL;
3020 	struct imsg imsg;
3021 	struct got_imsg_reused_deltas *ideltas;
3022 	size_t datalen;
3023 
3024 	*done = 0;
3025 	*ndeltas = 0;
3026 
3027 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3028 	if (err)
3029 		return err;
3030 
3031 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3032 	switch (imsg.hdr.type) {
3033 	case GOT_IMSG_REUSED_DELTAS:
3034 		if (datalen < sizeof(*ideltas)) {
3035 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3036 			break;
3037 		}
3038 		ideltas = imsg.data;
3039 		if (ideltas->ndeltas > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS) {
3040 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3041 			break;
3042 		}
3043 		*ndeltas = ideltas->ndeltas;
3044 		memcpy(deltas, (uint8_t *)imsg.data + sizeof(ideltas),
3045 		    *ndeltas * sizeof(*deltas));
3046 		break;
3047 	case GOT_IMSG_DELTA_REUSE_DONE:
3048 		*done = 1;
3049 		break;
3050 	default:
3051 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3052 		break;
3053 	}
3054 
3055 	imsg_free(&imsg);
3056 
3057 	return err;
3058 }
3059 
3060 const struct got_error *
3061 got_privsep_unveil_exec_helpers(void)
3062 {
3063 	const char *helpers[] = {
3064 	    GOT_PATH_PROG_READ_PACK,
3065 	    GOT_PATH_PROG_READ_OBJECT,
3066 	    GOT_PATH_PROG_READ_COMMIT,
3067 	    GOT_PATH_PROG_READ_TREE,
3068 	    GOT_PATH_PROG_READ_BLOB,
3069 	    GOT_PATH_PROG_READ_TAG,
3070 	    GOT_PATH_PROG_READ_GITCONFIG,
3071 	    GOT_PATH_PROG_READ_GOTCONFIG,
3072 	    GOT_PATH_PROG_READ_PATCH,
3073 	    GOT_PATH_PROG_FETCH_PACK,
3074 	    GOT_PATH_PROG_INDEX_PACK,
3075 	    GOT_PATH_PROG_SEND_PACK,
3076 	};
3077 	size_t i;
3078 
3079 	for (i = 0; i < nitems(helpers); i++) {
3080 		if (unveil(helpers[i], "x") == 0)
3081 			continue;
3082 		return got_error_from_errno2("unveil", helpers[i]);
3083 	}
3084 
3085 	return NULL;
3086 }
3087 
3088 void
3089 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
3090 {
3091 	if (close(imsg_fds[0]) == -1) {
3092 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3093 		_exit(1);
3094 	}
3095 
3096 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
3097 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3098 		_exit(1);
3099 	}
3100 
3101 	closefrom(GOT_IMSG_FD_CHILD + 1);
3102 
3103 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
3104 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
3105 		    strerror(errno));
3106 		_exit(1);
3107 	}
3108 }