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/uio.h>
20 #include <sys/wait.h>
21 
22 #include <ctype.h>
23 #include <limits.h>
24 #include <signal.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <errno.h>
29 #include <stdint.h>
30 #include <poll.h>
31 #include <unistd.h>
32 #include <zlib.h>
33 #include <time.h>
34 
35 #include "got_compat.h"
36 
37 #include "got_object.h"
38 #include "got_error.h"
39 #include "got_path.h"
40 #include "got_repository.h"
41 
42 #include "got_lib_sha1.h"
43 #include "got_lib_delta.h"
44 #include "got_lib_inflate.h"
45 #include "got_lib_object.h"
46 #include "got_lib_object_parse.h"
47 #include "got_lib_privsep.h"
48 #include "got_lib_pack.h"
49 
50 #include "got_privsep.h"
51 
52 #ifndef MIN
53 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
54 #endif
55 
56 #ifndef nitems
57 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
58 #endif
59 
60 static const struct got_error *
61 poll_fd(int fd, int events, int timeout)
62 {
63 	struct pollfd pfd[1];
64 	struct timespec ts;
65 	sigset_t sigset;
66 	int n;
67 
68 	pfd[0].fd = fd;
69 	pfd[0].events = events;
70 
71 	ts.tv_sec = timeout;
72 	ts.tv_nsec = 0;
73 
74 	if (sigemptyset(&sigset) == -1)
75 		return got_error_from_errno("sigemptyset");
76 	if (sigaddset(&sigset, SIGWINCH) == -1)
77 		return got_error_from_errno("sigaddset");
78 
79 	n = ppoll(pfd, 1, timeout == INFTIM ? NULL : &ts, &sigset);
80 	if (n == -1)
81 		return got_error_from_errno("ppoll");
82 	if (n == 0)
83 		return got_error(GOT_ERR_TIMEOUT);
84 	if (pfd[0].revents & (POLLERR | POLLNVAL))
85 		return got_error_from_errno("poll error");
86 	if (pfd[0].revents & (events | POLLHUP))
87 		return NULL;
88 
89 	return got_error(GOT_ERR_INTERRUPT);
90 }
91 
92 static const struct got_error *
93 read_imsg(struct imsgbuf *ibuf)
94 {
95 	const struct got_error *err;
96 	size_t n;
97 
98 	err = poll_fd(ibuf->fd, POLLIN, INFTIM);
99 	if (err)
100 		return err;
101 
102 	n = imsg_read(ibuf);
103 	if (n == -1) {
104 		if (errno == EAGAIN) /* Could be a file-descriptor leak. */
105 			return got_error(GOT_ERR_PRIVSEP_NO_FD);
106 		return got_error(GOT_ERR_PRIVSEP_READ);
107 	}
108 	if (n == 0)
109 		return got_error(GOT_ERR_PRIVSEP_PIPE);
110 
111 	return NULL;
112 }
113 
114 const struct got_error *
115 got_privsep_wait_for_child(pid_t pid)
116 {
117 	int child_status;
118 
119 	if (waitpid(pid, &child_status, 0) == -1)
120 		return got_error_from_errno("waitpid");
121 
122 	if (!WIFEXITED(child_status))
123 		return got_error(GOT_ERR_PRIVSEP_DIED);
124 
125 	if (WEXITSTATUS(child_status) != 0)
126 		return got_error(GOT_ERR_PRIVSEP_EXIT);
127 
128 	return NULL;
129 }
130 
131 static const struct got_error *
132 recv_imsg_error(struct imsg *imsg, size_t datalen)
133 {
134 	struct got_imsg_error *ierr;
135 
136 	if (datalen != sizeof(*ierr))
137 		return got_error(GOT_ERR_PRIVSEP_LEN);
138 
139 	ierr = imsg->data;
140 	if (ierr->code == GOT_ERR_ERRNO) {
141 		static struct got_error serr;
142 		serr.code = GOT_ERR_ERRNO;
143 		serr.msg = strerror(ierr->errno_code);
144 		return &serr;
145 	}
146 
147 	return got_error(ierr->code);
148 }
149 
150 const struct got_error *
151 got_privsep_recv_imsg(struct imsg *imsg, struct imsgbuf *ibuf,
152     size_t min_datalen)
153 {
154 	const struct got_error *err;
155 	ssize_t n;
156 
157 	n = imsg_get(ibuf, imsg);
158 	if (n == -1)
159 		return got_error_from_errno("imsg_get");
160 
161 	while (n == 0) {
162 		err = read_imsg(ibuf);
163 		if (err)
164 			return err;
165 		n = imsg_get(ibuf, imsg);
166 		if (n == -1)
167 			return got_error_from_errno("imsg_get");
168 	}
169 
170 	if (imsg->hdr.len < IMSG_HEADER_SIZE + min_datalen)
171 		return got_error(GOT_ERR_PRIVSEP_LEN);
172 
173 	if (imsg->hdr.type == GOT_IMSG_ERROR) {
174 		size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
175 		return recv_imsg_error(imsg, datalen);
176 	}
177 
178 	return NULL;
179 }
180 
181 /* Attempt to send an error in an imsg. Complain on stderr as a last resort. */
182 void
183 got_privsep_send_error(struct imsgbuf *ibuf, const struct got_error *err)
184 {
185 	const struct got_error *poll_err;
186 	struct got_imsg_error ierr;
187 	int ret;
188 
189 	ierr.code = err->code;
190 	if (err->code == GOT_ERR_ERRNO)
191 		ierr.errno_code = errno;
192 	else
193 		ierr.errno_code = 0;
194 	ret = imsg_compose(ibuf, GOT_IMSG_ERROR, 0, 0, -1, &ierr, sizeof(ierr));
195 	if (ret == -1) {
196 		fprintf(stderr, "%s: error %d \"%s\": imsg_compose: %s\n",
197 		    getprogname(), err->code, err->msg, strerror(errno));
198 		return;
199 	}
200 
201 	poll_err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
202 	if (poll_err) {
203 		fprintf(stderr, "%s: error %d \"%s\": poll: %s\n",
204 		    getprogname(), err->code, err->msg, poll_err->msg);
205 		return;
206 	}
207 
208 	ret = imsg_flush(ibuf);
209 	if (ret == -1) {
210 		fprintf(stderr, "%s: error %d \"%s\": imsg_flush: %s\n",
211 		    getprogname(), err->code, err->msg, strerror(errno));
212 		imsg_clear(ibuf);
213 		return;
214 	}
215 }
216 
217 static const struct got_error *
218 flush_imsg(struct imsgbuf *ibuf)
219 {
220 	const struct got_error *err;
221 
222 	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
223 	if (err)
224 		return err;
225 
226 	if (imsg_flush(ibuf) == -1) {
227 		imsg_clear(ibuf);
228 		return got_error_from_errno("imsg_flush");
229 	}
230 
231 	return NULL;
232 }
233 
234 const struct got_error *
235 got_privsep_flush_imsg(struct imsgbuf *ibuf)
236 {
237 	return flush_imsg(ibuf);
238 }
239 
240 const struct got_error *
241 got_privsep_send_stop(int fd)
242 {
243 	const struct got_error *err = NULL;
244 	struct imsgbuf ibuf;
245 
246 	imsg_init(&ibuf, fd);
247 
248 	if (imsg_compose(&ibuf, GOT_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
249 		return got_error_from_errno("imsg_compose STOP");
250 
251 	err = flush_imsg(&ibuf);
252 	return err;
253 }
254 
255 const struct got_error *
256 got_privsep_send_obj_req(struct imsgbuf *ibuf, int fd,
257     struct got_object_id *id)
258 {
259 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_REQUEST, 0, 0, fd,
260 	    id, sizeof(*id)) == -1)
261 		return got_error_from_errno("imsg_compose OBJECT_REQUEST");
262 
263 	return flush_imsg(ibuf);
264 }
265 
266 const struct got_error *
267 got_privsep_send_raw_obj_req(struct imsgbuf *ibuf, int fd,
268     struct got_object_id *id)
269 {
270 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_REQUEST, 0, 0, fd,
271 	    id, sizeof(*id)) == -1)
272 		return got_error_from_errno("imsg_compose RAW_OBJECT_REQUEST");
273 
274 	return flush_imsg(ibuf);
275 }
276 
277 const struct got_error *
278 got_privsep_send_raw_obj_outfd(struct imsgbuf *ibuf, int outfd)
279 {
280 	const struct got_error *err = NULL;
281 
282 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_OUTFD, 0, 0, outfd, NULL, 0)
283 	    == -1) {
284 		err = got_error_from_errno("imsg_compose RAW_OBJECT_OUTFD");
285 		close(outfd);
286 		return err;
287 	}
288 
289 	return flush_imsg(ibuf);
290 }
291 
292 const struct got_error *
293 got_privsep_send_raw_obj(struct imsgbuf *ibuf, off_t size, size_t hdrlen,
294     uint8_t *data)
295 {
296 	const struct got_error *err = NULL;
297 	struct got_imsg_raw_obj iobj;
298 	size_t len = sizeof(iobj);
299 	struct ibuf *wbuf;
300 
301 	memset(&iobj, 0, sizeof(iobj));
302 	iobj.hdrlen = hdrlen;
303 	iobj.size = size;
304 
305 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX)
306 		len += (size_t)size + hdrlen;
307 
308 	wbuf = imsg_create(ibuf, GOT_IMSG_RAW_OBJECT, 0, 0, len);
309 	if (wbuf == NULL) {
310 		err = got_error_from_errno("imsg_create RAW_OBJECT");
311 		return err;
312 	}
313 
314 	if (imsg_add(wbuf, &iobj, sizeof(iobj)) == -1)
315 		return got_error_from_errno("imsg_add RAW_OBJECT");
316 
317 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
318 		if (imsg_add(wbuf, data, size + hdrlen) == -1)
319 			return got_error_from_errno("imsg_add RAW_OBJECT");
320 	}
321 
322 	wbuf->fd = -1;
323 	imsg_close(ibuf, wbuf);
324 
325 	return flush_imsg(ibuf);
326 }
327 
328 const struct got_error *
329 got_privsep_recv_raw_obj(uint8_t **outbuf, off_t *size, size_t *hdrlen,
330     struct imsgbuf *ibuf)
331 {
332 	const struct got_error *err = NULL;
333 	struct imsg imsg;
334 	struct got_imsg_raw_obj *iobj;
335 	size_t datalen;
336 
337 	*outbuf = NULL;
338 
339 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
340 	if (err)
341 		return err;
342 
343 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
344 
345 	switch (imsg.hdr.type) {
346 	case GOT_IMSG_RAW_OBJECT:
347 		if (datalen < sizeof(*iobj)) {
348 			err = got_error(GOT_ERR_PRIVSEP_LEN);
349 			break;
350 		}
351 		iobj = imsg.data;
352 		*size = iobj->size;
353 		*hdrlen = iobj->hdrlen;
354 
355 		if (datalen == sizeof(*iobj)) {
356 			/* Data has been written to file descriptor. */
357 			break;
358 		}
359 
360 		if (*size < 0 ||
361 		    *size + *hdrlen > GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
362 			err = got_error(GOT_ERR_PRIVSEP_LEN);
363 			break;
364 		}
365 
366 		*outbuf = malloc(*size + *hdrlen);
367 		if (*outbuf == NULL) {
368 			err = got_error_from_errno("malloc");
369 			break;
370 		}
371 		memcpy(*outbuf, imsg.data + sizeof(*iobj), *size + *hdrlen);
372 		break;
373 	default:
374 		err = got_error(GOT_ERR_PRIVSEP_MSG);
375 		break;
376 	}
377 
378 	imsg_free(&imsg);
379 
380 	return err;
381 }
382 
383 const struct got_error *
384 got_privsep_send_commit_req(struct imsgbuf *ibuf, int fd,
385     struct got_object_id *id, int pack_idx)
386 {
387 	const struct got_error *err = NULL;
388 	struct got_imsg_packed_object iobj;
389 	void *data;
390 	size_t len;
391 
392 	memset(&iobj, 0, sizeof(iobj));
393 	if (pack_idx != -1) { /* commit is packed */
394 		iobj.idx = pack_idx;
395 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
396 		data = &iobj;
397 		len = sizeof(iobj);
398 	} else {
399 		data = id;
400 		len = sizeof(*id);
401 	}
402 
403 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_REQUEST, 0, 0, fd, data, len)
404 	    == -1) {
405 		err = got_error_from_errno("imsg_compose COMMIT_REQUEST");
406 		close(fd);
407 		return err;
408 	}
409 
410 	return flush_imsg(ibuf);
411 }
412 
413 const struct got_error *
414 got_privsep_send_tree_req(struct imsgbuf *ibuf, int fd,
415     struct got_object_id *id, int pack_idx)
416 {
417 	struct ibuf *wbuf;
418 	size_t len;
419 
420 	if (pack_idx != -1)
421 		len = sizeof(struct got_imsg_packed_object);
422 	else
423 		len = sizeof(*id);
424 
425 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_REQUEST, 0, 0, len);
426 	if (wbuf == NULL)
427 		return got_error_from_errno("imsg_create TREE_REQUEST");
428 
429 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1)
430 		return got_error_from_errno("imsg_add TREE_REQUEST");
431 
432 	if (pack_idx != -1) { /* tree is packed */
433 		if (imsg_add(wbuf, &pack_idx, sizeof(pack_idx)) == -1)
434 			return got_error_from_errno("imsg_add TREE_REQUEST");
435 	}
436 
437 	wbuf->fd = fd;
438 	imsg_close(ibuf, wbuf);
439 
440 	return flush_imsg(ibuf);
441 }
442 
443 const struct got_error *
444 got_privsep_send_tag_req(struct imsgbuf *ibuf, int fd,
445     struct got_object_id *id, int pack_idx)
446 {
447 	struct got_imsg_packed_object iobj;
448 	void *data;
449 	size_t len;
450 
451 	memset(&iobj, 0, sizeof(iobj));
452 	if (pack_idx != -1) { /* tag is packed */
453 		iobj.idx = pack_idx;
454 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
455 		data = &iobj;
456 		len = sizeof(iobj);
457 	} else {
458 		data = id;
459 		len = sizeof(*id);
460 	}
461 
462 	if (imsg_compose(ibuf, GOT_IMSG_TAG_REQUEST, 0, 0, fd, data, len)
463 	    == -1)
464 		return got_error_from_errno("imsg_compose TAG_REQUEST");
465 
466 	return flush_imsg(ibuf);
467 }
468 
469 const struct got_error *
470 got_privsep_send_blob_req(struct imsgbuf *ibuf, int infd,
471     struct got_object_id *id, int pack_idx)
472 {
473 	const struct got_error *err = NULL;
474 	struct got_imsg_packed_object iobj;
475 	void *data;
476 	size_t len;
477 
478 	memset(&iobj, 0, sizeof(iobj));
479 	if (pack_idx != -1) { /* blob is packed */
480 		iobj.idx = pack_idx;
481 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
482 		data = &iobj;
483 		len = sizeof(iobj);
484 	} else {
485 		data = id;
486 		len = sizeof(*id);
487 	}
488 
489 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_REQUEST, 0, 0, infd, data, len)
490 	    == -1) {
491 		err = got_error_from_errno("imsg_compose BLOB_REQUEST");
492 		close(infd);
493 		return err;
494 	}
495 
496 	return flush_imsg(ibuf);
497 }
498 
499 const struct got_error *
500 got_privsep_send_blob_outfd(struct imsgbuf *ibuf, int outfd)
501 {
502 	const struct got_error *err = NULL;
503 
504 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_OUTFD, 0, 0, outfd, NULL, 0)
505 	    == -1) {
506 		err = got_error_from_errno("imsg_compose BLOB_OUTFD");
507 		close(outfd);
508 		return err;
509 	}
510 
511 	return flush_imsg(ibuf);
512 }
513 
514 static const struct got_error *
515 send_fd(struct imsgbuf *ibuf, int imsg_code, int fd)
516 {
517 	const struct got_error *err = NULL;
518 
519 	if (imsg_compose(ibuf, imsg_code, 0, 0, fd, NULL, 0) == -1) {
520 		err = got_error_from_errno("imsg_compose TMPFD");
521 		close(fd);
522 		return err;
523 	}
524 
525 	return flush_imsg(ibuf);
526 }
527 
528 const struct got_error *
529 got_privsep_send_tmpfd(struct imsgbuf *ibuf, int fd)
530 {
531 	return send_fd(ibuf, GOT_IMSG_TMPFD, fd);
532 }
533 
534 const struct got_error *
535 got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj)
536 {
537 	struct got_imsg_object iobj;
538 
539 	memset(&iobj, 0, sizeof(iobj));
540 
541 	memcpy(iobj.id, obj->id.sha1, sizeof(iobj.id));
542 	iobj.type = obj->type;
543 	iobj.flags = obj->flags;
544 	iobj.hdrlen = obj->hdrlen;
545 	iobj.size = obj->size;
546 	if (iobj.flags & GOT_OBJ_FLAG_PACKED) {
547 		iobj.pack_offset = obj->pack_offset;
548 		iobj.pack_idx = obj->pack_idx;
549 	}
550 
551 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
552 	    == -1)
553 		return got_error_from_errno("imsg_compose OBJECT");
554 
555 	return flush_imsg(ibuf);
556 }
557 
558 const struct got_error *
559 got_privsep_send_fetch_req(struct imsgbuf *ibuf, int fd,
560     struct got_pathlist_head *have_refs, int fetch_all_branches,
561     struct got_pathlist_head *wanted_branches,
562     struct got_pathlist_head *wanted_refs, int list_refs_only, int verbosity)
563 {
564 	const struct got_error *err = NULL;
565 	struct ibuf *wbuf;
566 	size_t len;
567 	struct got_pathlist_entry *pe;
568 	struct got_imsg_fetch_request fetchreq;
569 
570 	memset(&fetchreq, 0, sizeof(fetchreq));
571 	fetchreq.fetch_all_branches = fetch_all_branches;
572 	fetchreq.list_refs_only = list_refs_only;
573 	fetchreq.verbosity = verbosity;
574 	TAILQ_FOREACH(pe, have_refs, entry)
575 		fetchreq.n_have_refs++;
576 	TAILQ_FOREACH(pe, wanted_branches, entry)
577 		fetchreq.n_wanted_branches++;
578 	TAILQ_FOREACH(pe, wanted_refs, entry)
579 		fetchreq.n_wanted_refs++;
580 	len = sizeof(struct got_imsg_fetch_request);
581 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
582 		close(fd);
583 		return got_error(GOT_ERR_NO_SPACE);
584 	}
585 
586 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_REQUEST, 0, 0, fd,
587 	    &fetchreq, sizeof(fetchreq)) == -1)
588 		return got_error_from_errno(
589 		    "imsg_compose FETCH_SERVER_PROGRESS");
590 
591 	err = flush_imsg(ibuf);
592 	if (err) {
593 		close(fd);
594 		return err;
595 	}
596 	fd = -1;
597 
598 	TAILQ_FOREACH(pe, have_refs, entry) {
599 		const char *name = pe->path;
600 		size_t name_len = pe->path_len;
601 		struct got_object_id *id = pe->data;
602 
603 		len = sizeof(struct got_imsg_fetch_have_ref) + name_len;
604 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_HAVE_REF, 0, 0, len);
605 		if (wbuf == NULL)
606 			return got_error_from_errno("imsg_create FETCH_HAVE_REF");
607 
608 		/* Keep in sync with struct got_imsg_fetch_have_ref! */
609 		if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1)
610 			return got_error_from_errno("imsg_add FETCH_HAVE_REF");
611 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
612 			return got_error_from_errno("imsg_add FETCH_HAVE_REF");
613 		if (imsg_add(wbuf, name, name_len) == -1)
614 			return got_error_from_errno("imsg_add FETCH_HAVE_REF");
615 
616 		wbuf->fd = -1;
617 		imsg_close(ibuf, wbuf);
618 		err = flush_imsg(ibuf);
619 		if (err)
620 			return err;
621 	}
622 
623 	TAILQ_FOREACH(pe, wanted_branches, entry) {
624 		const char *name = pe->path;
625 		size_t name_len = pe->path_len;
626 
627 		len = sizeof(struct got_imsg_fetch_wanted_branch) + name_len;
628 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_BRANCH, 0, 0,
629 		    len);
630 		if (wbuf == NULL)
631 			return got_error_from_errno(
632 			    "imsg_create FETCH_WANTED_BRANCH");
633 
634 		/* Keep in sync with struct got_imsg_fetch_wanted_branch! */
635 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
636 			return got_error_from_errno(
637 			    "imsg_add FETCH_WANTED_BRANCH");
638 		if (imsg_add(wbuf, name, name_len) == -1)
639 			return got_error_from_errno(
640 			    "imsg_add FETCH_WANTED_BRANCH");
641 
642 		wbuf->fd = -1;
643 		imsg_close(ibuf, wbuf);
644 		err = flush_imsg(ibuf);
645 		if (err)
646 			return err;
647 	}
648 
649 	TAILQ_FOREACH(pe, wanted_refs, entry) {
650 		const char *name = pe->path;
651 		size_t name_len = pe->path_len;
652 
653 		len = sizeof(struct got_imsg_fetch_wanted_ref) + name_len;
654 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_REF, 0, 0,
655 		    len);
656 		if (wbuf == NULL)
657 			return got_error_from_errno(
658 			    "imsg_create FETCH_WANTED_REF");
659 
660 		/* Keep in sync with struct got_imsg_fetch_wanted_ref! */
661 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
662 			return got_error_from_errno(
663 			    "imsg_add FETCH_WANTED_REF");
664 		if (imsg_add(wbuf, name, name_len) == -1)
665 			return got_error_from_errno(
666 			    "imsg_add FETCH_WANTED_REF");
667 
668 		wbuf->fd = -1;
669 		imsg_close(ibuf, wbuf);
670 		err = flush_imsg(ibuf);
671 		if (err)
672 			return err;
673 	}
674 
675 
676 	return NULL;
677 
678 }
679 
680 const struct got_error *
681 got_privsep_send_fetch_outfd(struct imsgbuf *ibuf, int fd)
682 {
683 	return send_fd(ibuf, GOT_IMSG_FETCH_OUTFD, fd);
684 }
685 
686 const struct got_error *
687 got_privsep_recv_fetch_progress(int *done, struct got_object_id **id,
688     char **refname, struct got_pathlist_head *symrefs, char **server_progress,
689     off_t *packfile_size, uint8_t *pack_sha1, struct imsgbuf *ibuf)
690 {
691 	const struct got_error *err = NULL;
692 	struct imsg imsg;
693 	size_t datalen;
694 	struct got_imsg_fetch_symrefs *isymrefs = NULL;
695 	size_t n, remain;
696 	off_t off;
697 	int i;
698 
699 	*done = 0;
700 	*id = NULL;
701 	*refname = NULL;
702 	*server_progress = NULL;
703 	*packfile_size = 0;
704 	memset(pack_sha1, 0, SHA1_DIGEST_LENGTH);
705 
706 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
707 	if (err)
708 		return err;
709 
710 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
711 	switch (imsg.hdr.type) {
712 	case GOT_IMSG_ERROR:
713 		err = recv_imsg_error(&imsg, datalen);
714 		break;
715 	case GOT_IMSG_FETCH_SYMREFS:
716 		if (datalen < sizeof(*isymrefs)) {
717 			err = got_error(GOT_ERR_PRIVSEP_LEN);
718 			break;
719 		}
720 		if (isymrefs != NULL) {
721 			err = got_error(GOT_ERR_PRIVSEP_MSG);
722 			break;
723 		}
724 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
725 		off = sizeof(*isymrefs);
726 		remain = datalen - off;
727 		for (n = 0; n < isymrefs->nsymrefs; n++) {
728 			struct got_imsg_fetch_symref *s;
729 			char *name, *target;
730 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
731 				err = got_error(GOT_ERR_PRIVSEP_LEN);
732 				goto done;
733 			}
734 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
735 			off += sizeof(*s);
736 			remain -= sizeof(*s);
737 			if (remain < s->name_len) {
738 				err = got_error(GOT_ERR_PRIVSEP_LEN);
739 				goto done;
740 			}
741 			name = strndup(imsg.data + off, s->name_len);
742 			if (name == NULL) {
743 				err = got_error_from_errno("strndup");
744 				goto done;
745 			}
746 			off += s->name_len;
747 			remain -= s->name_len;
748 			if (remain < s->target_len) {
749 				err = got_error(GOT_ERR_PRIVSEP_LEN);
750 				free(name);
751 				goto done;
752 			}
753 			target = strndup(imsg.data + off, s->target_len);
754 			if (target == NULL) {
755 				err = got_error_from_errno("strndup");
756 				free(name);
757 				goto done;
758 			}
759 			off += s->target_len;
760 			remain -= s->target_len;
761 			err = got_pathlist_append(symrefs, name, target);
762 			if (err) {
763 				free(name);
764 				free(target);
765 				goto done;
766 			}
767 		}
768 		break;
769 	case GOT_IMSG_FETCH_REF:
770 		if (datalen <= SHA1_DIGEST_LENGTH) {
771 			err = got_error(GOT_ERR_PRIVSEP_MSG);
772 			break;
773 		}
774 		*id = malloc(sizeof(**id));
775 		if (*id == NULL) {
776 			err = got_error_from_errno("malloc");
777 			break;
778 		}
779 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
780 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
781 		    datalen - SHA1_DIGEST_LENGTH);
782 		if (*refname == NULL) {
783 			err = got_error_from_errno("strndup");
784 			break;
785 		}
786 		break;
787 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
788 		if (datalen == 0) {
789 			err = got_error(GOT_ERR_PRIVSEP_LEN);
790 			break;
791 		}
792 		*server_progress = strndup(imsg.data, datalen);
793 		if (*server_progress == NULL) {
794 			err = got_error_from_errno("strndup");
795 			break;
796 		}
797 		for (i = 0; i < datalen; i++) {
798 			if (!isprint((unsigned char)(*server_progress)[i]) &&
799 			    !isspace((unsigned char)(*server_progress)[i])) {
800 				err = got_error(GOT_ERR_PRIVSEP_MSG);
801 				free(*server_progress);
802 				*server_progress = NULL;
803 				goto done;
804 			}
805 		}
806 		break;
807 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
808 		if (datalen < sizeof(*packfile_size)) {
809 			err = got_error(GOT_ERR_PRIVSEP_MSG);
810 			break;
811 		}
812 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
813 		break;
814 	case GOT_IMSG_FETCH_DONE:
815 		if (datalen != SHA1_DIGEST_LENGTH) {
816 			err = got_error(GOT_ERR_PRIVSEP_MSG);
817 			break;
818 		}
819 		memcpy(pack_sha1, imsg.data, SHA1_DIGEST_LENGTH);
820 		*done = 1;
821 		break;
822 	default:
823 		err = got_error(GOT_ERR_PRIVSEP_MSG);
824 		break;
825 	}
826 done:
827 	if (err) {
828 		free(*id);
829 		*id = NULL;
830 		free(*refname);
831 		*refname = NULL;
832 	}
833 	imsg_free(&imsg);
834 	return err;
835 }
836 
837 static const struct got_error *
838 send_send_ref(const char *name, size_t name_len, struct got_object_id *id,
839     int delete, struct imsgbuf *ibuf)
840 {
841 	size_t len;
842 	struct ibuf *wbuf;
843 
844 	len = sizeof(struct got_imsg_send_ref) + name_len;
845 	wbuf = imsg_create(ibuf, GOT_IMSG_SEND_REF, 0, 0, len);
846 	if (wbuf == NULL)
847 		return got_error_from_errno("imsg_create SEND_REF");
848 
849 	/* Keep in sync with struct got_imsg_send_ref! */
850 	if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1)
851 		return got_error_from_errno("imsg_add SEND_REF");
852 	if (imsg_add(wbuf, &delete, sizeof(delete)) == -1)
853 		return got_error_from_errno("imsg_add SEND_REF");
854 	if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
855 		return got_error_from_errno("imsg_add SEND_REF");
856 	if (imsg_add(wbuf, name, name_len) == -1)
857 		return got_error_from_errno("imsg_add SEND_REF");
858 
859 	wbuf->fd = -1;
860 	imsg_close(ibuf, wbuf);
861 	return flush_imsg(ibuf);
862 }
863 
864 const struct got_error *
865 got_privsep_send_send_req(struct imsgbuf *ibuf, int fd,
866     struct got_pathlist_head *have_refs,
867     struct got_pathlist_head *delete_refs,
868     int verbosity)
869 {
870 	const struct got_error *err = NULL;
871 	struct got_pathlist_entry *pe;
872 	struct got_imsg_send_request sendreq;
873 	struct got_object_id zero_id;
874 
875 	memset(&zero_id, 0, sizeof(zero_id));
876 	memset(&sendreq, 0, sizeof(sendreq));
877 	sendreq.verbosity = verbosity;
878 	TAILQ_FOREACH(pe, have_refs, entry)
879 		sendreq.nrefs++;
880 	TAILQ_FOREACH(pe, delete_refs, entry)
881 		sendreq.nrefs++;
882 	if (imsg_compose(ibuf, GOT_IMSG_SEND_REQUEST, 0, 0, fd,
883 	    &sendreq, sizeof(sendreq)) == -1) {
884 		err = got_error_from_errno(
885 		    "imsg_compose FETCH_SERVER_PROGRESS");
886 		goto done;
887 	}
888 
889 	err = flush_imsg(ibuf);
890 	if (err)
891 		goto done;
892 	fd = -1;
893 
894 	TAILQ_FOREACH(pe, have_refs, entry) {
895 		const char *name = pe->path;
896 		size_t name_len = pe->path_len;
897 		struct got_object_id *id = pe->data;
898 		err = send_send_ref(name, name_len, id, 0, ibuf);
899 		if (err)
900 			goto done;
901 	}
902 
903 	TAILQ_FOREACH(pe, delete_refs, entry) {
904 		const char *name = pe->path;
905 		size_t name_len = pe->path_len;
906 		err = send_send_ref(name, name_len, &zero_id, 1, ibuf);
907 		if (err)
908 			goto done;
909 	}
910 done:
911 	if (fd != -1 && close(fd) == -1 && err == NULL)
912 		err = got_error_from_errno("close");
913 	return err;
914 
915 }
916 
917 const struct got_error *
918 got_privsep_recv_send_remote_refs(struct got_pathlist_head *remote_refs,
919     struct imsgbuf *ibuf)
920 {
921 	const struct got_error *err = NULL;
922 	struct imsg imsg;
923 	size_t datalen;
924 	int done = 0;
925 	struct got_imsg_send_remote_ref iremote_ref;
926 	struct got_object_id *id = NULL;
927 	char *refname = NULL;
928 	struct got_pathlist_entry *new;
929 
930 	while (!done) {
931 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
932 		if (err)
933 			return err;
934 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
935 		switch (imsg.hdr.type) {
936 		case GOT_IMSG_ERROR:
937 			err = recv_imsg_error(&imsg, datalen);
938 			goto done;
939 		case GOT_IMSG_SEND_REMOTE_REF:
940 			if (datalen < sizeof(iremote_ref)) {
941 				err = got_error(GOT_ERR_PRIVSEP_MSG);
942 				goto done;
943 			}
944 			memcpy(&iremote_ref, imsg.data, sizeof(iremote_ref));
945 			if (datalen != sizeof(iremote_ref) +
946 			    iremote_ref.name_len) {
947 				err = got_error(GOT_ERR_PRIVSEP_MSG);
948 				goto done;
949 			}
950 			id = malloc(sizeof(*id));
951 			if (id == NULL) {
952 				err = got_error_from_errno("malloc");
953 				goto done;
954 			}
955 			memcpy(id->sha1, iremote_ref.id, SHA1_DIGEST_LENGTH);
956 			refname = strndup(imsg.data + sizeof(iremote_ref),
957 			    datalen - sizeof(iremote_ref));
958 			if (refname == NULL) {
959 				err = got_error_from_errno("strndup");
960 				goto done;
961 			}
962 			err = got_pathlist_insert(&new, remote_refs,
963 			    refname, id);
964 			if (err)
965 				goto done;
966 			if (new == NULL) { /* duplicate which wasn't inserted */
967 				free(id);
968 				free(refname);
969 			}
970 			id = NULL;
971 			refname = NULL;
972 			break;
973 		case GOT_IMSG_SEND_PACK_REQUEST:
974 			if (datalen != 0) {
975 				err = got_error(GOT_ERR_PRIVSEP_MSG);
976 				goto done;
977 			}
978 			/* got-send-pack is now waiting for a pack file. */
979 			done = 1;
980 			break;
981 		default:
982 			err = got_error(GOT_ERR_PRIVSEP_MSG);
983 			break;
984 		}
985 	}
986 done:
987 	free(id);
988 	free(refname);
989 	imsg_free(&imsg);
990 	return err;
991 }
992 
993 const struct got_error *
994 got_privsep_send_packfd(struct imsgbuf *ibuf, int fd)
995 {
996 	return send_fd(ibuf, GOT_IMSG_SEND_PACKFD, fd);
997 }
998 
999 const struct got_error *
1000 got_privsep_recv_send_progress(int *done, off_t *bytes_sent,
1001     int *success, char **refname, struct imsgbuf *ibuf)
1002 {
1003 	const struct got_error *err = NULL;
1004 	struct imsg imsg;
1005 	size_t datalen;
1006 	struct got_imsg_send_ref_status iref_status;
1007 
1008 	/* Do not reset the current value of 'bytes_sent', it accumulates. */
1009 	*done = 0;
1010 	*success = 0;
1011 	*refname = NULL;
1012 
1013 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1014 	if (err)
1015 		return err;
1016 
1017 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1018 	switch (imsg.hdr.type) {
1019 	case GOT_IMSG_ERROR:
1020 		err = recv_imsg_error(&imsg, datalen);
1021 		break;
1022 	case GOT_IMSG_SEND_UPLOAD_PROGRESS:
1023 		if (datalen < sizeof(*bytes_sent)) {
1024 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1025 			break;
1026 		}
1027 		memcpy(bytes_sent, imsg.data, sizeof(*bytes_sent));
1028 		break;
1029 	case GOT_IMSG_SEND_REF_STATUS:
1030 		if (datalen < sizeof(iref_status)) {
1031 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1032 			break;
1033 		}
1034 		memcpy(&iref_status, imsg.data, sizeof(iref_status));
1035 		if (datalen != sizeof(iref_status) + iref_status.name_len) {
1036 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1037 			break;
1038 		}
1039 		*success = iref_status.success;
1040 		*refname = strndup(imsg.data + sizeof(iref_status),
1041 		    iref_status.name_len);
1042 		break;
1043 	case GOT_IMSG_SEND_DONE:
1044 		if (datalen != 0) {
1045 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1046 			break;
1047 		}
1048 		*done = 1;
1049 		break;
1050 	default:
1051 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1052 		break;
1053 	}
1054 
1055 	imsg_free(&imsg);
1056 	return err;
1057 }
1058 
1059 const struct got_error *
1060 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_sha1,
1061     int fd)
1062 {
1063 	const struct got_error *err = NULL;
1064 
1065 	/* Keep in sync with struct got_imsg_index_pack_request */
1066 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
1067 	    pack_sha1, SHA1_DIGEST_LENGTH) == -1) {
1068 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
1069 		close(fd);
1070 		return err;
1071 	}
1072 	return flush_imsg(ibuf);
1073 }
1074 
1075 const struct got_error *
1076 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
1077 {
1078 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
1079 }
1080 
1081 const struct got_error *
1082 got_privsep_recv_index_progress(int *done, int *nobj_total,
1083     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
1084     struct imsgbuf *ibuf)
1085 {
1086 	const struct got_error *err = NULL;
1087 	struct imsg imsg;
1088 	struct got_imsg_index_pack_progress *iprogress;
1089 	size_t datalen;
1090 
1091 	*done = 0;
1092 	*nobj_total = 0;
1093 	*nobj_indexed = 0;
1094 	*nobj_resolved = 0;
1095 
1096 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1097 	if (err)
1098 		return err;
1099 
1100 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1101 	switch (imsg.hdr.type) {
1102 	case GOT_IMSG_ERROR:
1103 		err = recv_imsg_error(&imsg, datalen);
1104 		break;
1105 	case GOT_IMSG_IDXPACK_PROGRESS:
1106 		if (datalen < sizeof(*iprogress)) {
1107 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1108 			break;
1109 		}
1110 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
1111 		if (iprogress->nobj_total < 0 || iprogress->nobj_indexed < 0 ||
1112 		    iprogress->nobj_loose < 0 || iprogress->nobj_resolved < 0) {
1113 			err = got_error(GOT_ERR_RANGE);
1114 			break;
1115 		}
1116 		*nobj_total = iprogress->nobj_total;
1117 		*nobj_indexed = iprogress->nobj_indexed;
1118 		*nobj_loose = iprogress->nobj_loose;
1119 		*nobj_resolved = iprogress->nobj_resolved;
1120 		break;
1121 	case GOT_IMSG_IDXPACK_DONE:
1122 		if (datalen != 0) {
1123 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1124 			break;
1125 		}
1126 		*done = 1;
1127 		break;
1128 	default:
1129 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1130 		break;
1131 	}
1132 
1133 	imsg_free(&imsg);
1134 	return err;
1135 }
1136 
1137 const struct got_error *
1138 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
1139     struct imsgbuf *ibuf)
1140 {
1141 	struct got_imsg_object *iobj;
1142 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1143 
1144 	if (datalen != sizeof(*iobj))
1145 		return got_error(GOT_ERR_PRIVSEP_LEN);
1146 	iobj = imsg->data;
1147 
1148 	if (iobj->pack_offset < 0)
1149 		return got_error(GOT_ERR_PACK_OFFSET);
1150 
1151 	*obj = calloc(1, sizeof(**obj));
1152 	if (*obj == NULL)
1153 		return got_error_from_errno("calloc");
1154 
1155 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
1156 	(*obj)->type = iobj->type;
1157 	(*obj)->flags = iobj->flags;
1158 	(*obj)->hdrlen = iobj->hdrlen;
1159 	(*obj)->size = iobj->size;
1160 	/* path_packfile is handled by caller */
1161 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
1162 		(*obj)->pack_offset = iobj->pack_offset;
1163 		(*obj)->pack_idx = iobj->pack_idx;
1164 	}
1165 	STAILQ_INIT(&(*obj)->deltas.entries);
1166 	return NULL;
1167 }
1168 
1169 const struct got_error *
1170 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
1171 {
1172 	const struct got_error *err = NULL;
1173 	struct imsg imsg;
1174 	const size_t min_datalen =
1175 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
1176 
1177 	*obj = NULL;
1178 
1179 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1180 	if (err)
1181 		return err;
1182 
1183 	switch (imsg.hdr.type) {
1184 	case GOT_IMSG_OBJECT:
1185 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
1186 		break;
1187 	default:
1188 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1189 		break;
1190 	}
1191 
1192 	imsg_free(&imsg);
1193 
1194 	return err;
1195 }
1196 
1197 static const struct got_error *
1198 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
1199     size_t logmsg_len)
1200 {
1201 	const struct got_error *err = NULL;
1202 	size_t offset, remain;
1203 
1204 	offset = 0;
1205 	remain = logmsg_len;
1206 	while (remain > 0) {
1207 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1208 
1209 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
1210 		    commit->logmsg + offset, n) == -1) {
1211 			err = got_error_from_errno("imsg_compose "
1212 			    "COMMIT_LOGMSG");
1213 			break;
1214 		}
1215 
1216 		err = flush_imsg(ibuf);
1217 		if (err)
1218 			break;
1219 
1220 		offset += n;
1221 		remain -= n;
1222 	}
1223 
1224 	return err;
1225 }
1226 
1227 const struct got_error *
1228 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
1229 {
1230 	const struct got_error *err = NULL;
1231 	struct got_imsg_commit_object *icommit;
1232 	uint8_t *buf;
1233 	size_t len, total;
1234 	struct got_object_qid *qid;
1235 	size_t author_len = strlen(commit->author);
1236 	size_t committer_len = strlen(commit->committer);
1237 	size_t logmsg_len = strlen(commit->logmsg);
1238 
1239 	total = sizeof(*icommit) + author_len + committer_len +
1240 	    commit->nparents * SHA1_DIGEST_LENGTH;
1241 
1242 	buf = malloc(total);
1243 	if (buf == NULL)
1244 		return got_error_from_errno("malloc");
1245 
1246 	icommit = (struct got_imsg_commit_object *)buf;
1247 	memcpy(icommit->tree_id, commit->tree_id->sha1,
1248 	    sizeof(icommit->tree_id));
1249 	icommit->author_len = author_len;
1250 	icommit->author_time = commit->author_time;
1251 	icommit->author_gmtoff = commit->author_gmtoff;
1252 	icommit->committer_len = committer_len;
1253 	icommit->committer_time = commit->committer_time;
1254 	icommit->committer_gmtoff = commit->committer_gmtoff;
1255 	icommit->logmsg_len = logmsg_len;
1256 	icommit->nparents = commit->nparents;
1257 
1258 	len = sizeof(*icommit);
1259 	memcpy(buf + len, commit->author, author_len);
1260 	len += author_len;
1261 	memcpy(buf + len, commit->committer, committer_len);
1262 	len += committer_len;
1263 	STAILQ_FOREACH(qid, &commit->parent_ids, entry) {
1264 		memcpy(buf + len, &qid->id, SHA1_DIGEST_LENGTH);
1265 		len += SHA1_DIGEST_LENGTH;
1266 	}
1267 
1268 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
1269 		err = got_error_from_errno("imsg_compose COMMIT");
1270 		goto done;
1271 	}
1272 
1273 	if (logmsg_len == 0 ||
1274 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1275 		err = flush_imsg(ibuf);
1276 		if (err)
1277 			goto done;
1278 	}
1279 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
1280 done:
1281 	free(buf);
1282 	return err;
1283 }
1284 
1285 static const struct got_error *
1286 get_commit_from_imsg(struct got_commit_object **commit,
1287     struct imsg *imsg, size_t datalen, struct imsgbuf *ibuf)
1288 {
1289 	const struct got_error *err = NULL;
1290 	struct got_imsg_commit_object *icommit;
1291 	size_t len = 0;
1292 	int i;
1293 
1294 	if (datalen < sizeof(*icommit))
1295 		return got_error(GOT_ERR_PRIVSEP_LEN);
1296 
1297 	icommit = imsg->data;
1298 	if (datalen != sizeof(*icommit) + icommit->author_len +
1299 	    icommit->committer_len +
1300 	    icommit->nparents * SHA1_DIGEST_LENGTH)
1301 		return got_error(GOT_ERR_PRIVSEP_LEN);
1302 
1303 	if (icommit->nparents < 0)
1304 		return got_error(GOT_ERR_PRIVSEP_LEN);
1305 
1306 	len += sizeof(*icommit);
1307 
1308 	*commit = got_object_commit_alloc_partial();
1309 	if (*commit == NULL)
1310 		return got_error_from_errno(
1311 		    "got_object_commit_alloc_partial");
1312 
1313 	memcpy((*commit)->tree_id->sha1, icommit->tree_id,
1314 	    SHA1_DIGEST_LENGTH);
1315 	(*commit)->author_time = icommit->author_time;
1316 	(*commit)->author_gmtoff = icommit->author_gmtoff;
1317 	(*commit)->committer_time = icommit->committer_time;
1318 	(*commit)->committer_gmtoff = icommit->committer_gmtoff;
1319 
1320 	(*commit)->author = strndup(imsg->data + len, icommit->author_len);
1321 	if ((*commit)->author == NULL) {
1322 		err = got_error_from_errno("strndup");
1323 		goto done;
1324 	}
1325 	len += icommit->author_len;
1326 
1327 	(*commit)->committer = strndup(imsg->data + len,
1328 	    icommit->committer_len);
1329 	if ((*commit)->committer == NULL) {
1330 		err = got_error_from_errno("strndup");
1331 		goto done;
1332 	}
1333 	len += icommit->committer_len;
1334 
1335 	if (icommit->logmsg_len == 0) {
1336 		(*commit)->logmsg = strdup("");
1337 		if ((*commit)->logmsg == NULL) {
1338 			err = got_error_from_errno("strdup");
1339 			goto done;
1340 		}
1341 	} else {
1342 		size_t offset = 0, remain = icommit->logmsg_len;
1343 
1344 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1345 		if ((*commit)->logmsg == NULL) {
1346 			err = got_error_from_errno("malloc");
1347 			goto done;
1348 		}
1349 		while (remain > 0) {
1350 			struct imsg imsg_log;
1351 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1352 			    remain);
1353 
1354 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1355 			if (err)
1356 				goto done;
1357 
1358 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1359 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1360 				goto done;
1361 			}
1362 
1363 			memcpy((*commit)->logmsg + offset,
1364 			    imsg_log.data, n);
1365 			imsg_free(&imsg_log);
1366 			offset += n;
1367 			remain -= n;
1368 		}
1369 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1370 	}
1371 
1372 	for (i = 0; i < icommit->nparents; i++) {
1373 		struct got_object_qid *qid;
1374 
1375 		err = got_object_qid_alloc_partial(&qid);
1376 		if (err)
1377 			break;
1378 		memcpy(&qid->id, imsg->data + len +
1379 		    i * SHA1_DIGEST_LENGTH, sizeof(qid->id));
1380 		STAILQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1381 		(*commit)->nparents++;
1382 	}
1383 done:
1384 	if (err) {
1385 		got_object_commit_close(*commit);
1386 		*commit = NULL;
1387 	}
1388 	return err;
1389 }
1390 
1391 const struct got_error *
1392 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1393 {
1394 	const struct got_error *err = NULL;
1395 	struct imsg imsg;
1396 	size_t datalen;
1397 	const size_t min_datalen =
1398 	    MIN(sizeof(struct got_imsg_error),
1399 	    sizeof(struct got_imsg_commit_object));
1400 
1401 	*commit = NULL;
1402 
1403 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1404 	if (err)
1405 		return err;
1406 
1407 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1408 
1409 	switch (imsg.hdr.type) {
1410 	case GOT_IMSG_COMMIT:
1411 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1412 		break;
1413 	default:
1414 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1415 		break;
1416 	}
1417 
1418 	imsg_free(&imsg);
1419 
1420 	return err;
1421 }
1422 
1423 static const struct got_error *
1424 send_tree_entries_batch(struct imsgbuf *ibuf,
1425     struct got_parsed_tree_entry *entries, int idx0, int idxN, size_t len)
1426 {
1427 	struct ibuf *wbuf;
1428 	struct got_imsg_tree_entries ientries;
1429 	int i;
1430 
1431 	memset(&ientries, 0, sizeof(ientries));
1432 
1433 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRIES, 0, 0, len);
1434 	if (wbuf == NULL)
1435 		return got_error_from_errno("imsg_create TREE_ENTRY");
1436 
1437 	ientries.nentries = idxN - idx0 + 1;
1438 	if (imsg_add(wbuf, &ientries, sizeof(ientries)) == -1)
1439 		return got_error_from_errno("imsg_add TREE_ENTRY");
1440 
1441 	for (i = idx0; i <= idxN; i++) {
1442 		struct got_parsed_tree_entry *pte = &entries[i];
1443 
1444 		/* Keep in sync with struct got_imsg_tree_object definition! */
1445 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1)
1446 			return got_error_from_errno("imsg_add TREE_ENTRY");
1447 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1)
1448 			return got_error_from_errno("imsg_add TREE_ENTRY");
1449 		if (imsg_add(wbuf, &pte->namelen, sizeof(pte->namelen)) == -1)
1450 			return got_error_from_errno("imsg_add TREE_ENTRY");
1451 
1452 		/* Remaining bytes are the entry's name. */
1453 		if (imsg_add(wbuf, pte->name, pte->namelen) == -1)
1454 			return got_error_from_errno("imsg_add TREE_ENTRY");
1455 	}
1456 
1457 	wbuf->fd = -1;
1458 	imsg_close(ibuf, wbuf);
1459 	return NULL;
1460 }
1461 
1462 static const struct got_error *
1463 send_tree_entries(struct imsgbuf *ibuf, struct got_parsed_tree_entry *entries,
1464     int nentries)
1465 {
1466 	const struct got_error *err = NULL;
1467 	int i, j;
1468 	size_t entries_len = sizeof(struct got_imsg_tree_entries);
1469 
1470 	i = 0;
1471 	for (j = 0; j < nentries; j++) {
1472 		struct got_parsed_tree_entry *pte = &entries[j];
1473 		size_t len = sizeof(*pte) + pte->namelen;
1474 
1475 		if (j > 0 &&
1476 		    entries_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1477 			err = send_tree_entries_batch(ibuf, entries,
1478 			    i, j - 1, entries_len);
1479 			if (err)
1480 				return err;
1481 			i = j;
1482 			entries_len = sizeof(struct got_imsg_tree_entries);
1483 		}
1484 
1485 		entries_len += len;
1486 	}
1487 
1488 	if (j > 0) {
1489 		err = send_tree_entries_batch(ibuf, entries, i, j - 1,
1490 		    entries_len);
1491 		if (err)
1492 			return err;
1493 	}
1494 
1495 	return NULL;
1496 }
1497 
1498 const struct got_error *
1499 got_privsep_send_tree(struct imsgbuf *ibuf,
1500     struct got_parsed_tree_entry *entries, int nentries)
1501 {
1502 	const struct got_error *err = NULL;
1503 	struct got_imsg_tree_object itree;
1504 
1505 	memset(&itree, 0, sizeof(itree));
1506 	itree.nentries = nentries;
1507 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1508 	    == -1)
1509 		return got_error_from_errno("imsg_compose TREE");
1510 
1511 	err = send_tree_entries(ibuf, entries, nentries);
1512 	if (err)
1513 		return err;
1514 
1515 	return flush_imsg(ibuf);
1516 }
1517 
1518 
1519 static const struct got_error *
1520 recv_tree_entries(void *data, size_t datalen, struct got_tree_object *tree,
1521     int *nentries)
1522 {
1523 	const struct got_error *err = NULL;
1524 	struct got_imsg_tree_entries *ientries;
1525 	struct got_tree_entry *te;
1526 	size_t te_offset;
1527 	size_t i;
1528 
1529 	if (datalen <= sizeof(*ientries) ||
1530 	    datalen > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
1531 		return got_error(GOT_ERR_PRIVSEP_LEN);
1532 
1533 	ientries = (struct got_imsg_tree_entries *)data;
1534 	if (ientries->nentries > INT_MAX) {
1535 		return got_error_msg(GOT_ERR_NO_SPACE,
1536 		    "too many tree entries");
1537 	}
1538 
1539 	te_offset = sizeof(*ientries);
1540 	for (i = 0; i < ientries->nentries; i++) {
1541 		struct got_imsg_tree_entry ite;
1542 		const char *te_name;
1543 		uint8_t *buf = (uint8_t *)data + te_offset;
1544 
1545 		if (te_offset >= datalen) {
1546 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1547 			break;
1548 		}
1549 
1550 		/* Might not be aligned, size is ~32 bytes. */
1551 		memcpy(&ite, buf, sizeof(ite));
1552 
1553 		if (ite.namelen >= sizeof(te->name)) {
1554 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1555 			break;
1556 		}
1557 		if (te_offset + sizeof(ite) + ite.namelen > datalen) {
1558 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1559 			break;
1560 		}
1561 
1562 		if (*nentries >= tree->nentries) {
1563 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1564 			break;
1565 		}
1566 		te = &tree->entries[*nentries];
1567 		te_name = buf + sizeof(ite);
1568 		memcpy(te->name, te_name, ite.namelen);
1569 		te->name[ite.namelen] = '\0';
1570 		memcpy(te->id.sha1, ite.id, SHA1_DIGEST_LENGTH);
1571 		te->mode = ite.mode;
1572 		te->idx = *nentries;
1573 		(*nentries)++;
1574 
1575 		te_offset += sizeof(ite) + ite.namelen;
1576 	}
1577 
1578 	return err;
1579 }
1580 
1581 const struct got_error *
1582 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1583 {
1584 	const struct got_error *err = NULL;
1585 	const size_t min_datalen =
1586 	    MIN(sizeof(struct got_imsg_error),
1587 	    sizeof(struct got_imsg_tree_object));
1588 	struct got_imsg_tree_object *itree;
1589 	int nentries = 0;
1590 
1591 	*tree = NULL;
1592 
1593 	err = read_imsg(ibuf);
1594 	if (err)
1595 		goto done;
1596 
1597 	for (;;) {
1598 		struct imsg imsg;
1599 		size_t n;
1600 		size_t datalen;
1601 
1602 		n = imsg_get(ibuf, &imsg);
1603 		if (n == 0) {
1604 			if ((*tree)) {
1605 				if (nentries < (*tree)->nentries) {
1606 					err = read_imsg(ibuf);
1607 					if (err)
1608 						break;
1609 					continue;
1610 				} else
1611 					break;
1612 			} else {
1613 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1614 				break;
1615 			}
1616 		}
1617 
1618 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen) {
1619 			imsg_free(&imsg);
1620 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1621 			break;
1622 		}
1623 
1624 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1625 
1626 		switch (imsg.hdr.type) {
1627 		case GOT_IMSG_ERROR:
1628 			err = recv_imsg_error(&imsg, datalen);
1629 			break;
1630 		case GOT_IMSG_TREE:
1631 			/* This message should only appear once. */
1632 			if (*tree != NULL) {
1633 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1634 				break;
1635 			}
1636 			if (datalen != sizeof(*itree)) {
1637 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1638 				break;
1639 			}
1640 			itree = imsg.data;
1641 			if (itree->nentries < 0) {
1642 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1643 				break;
1644 			}
1645 			*tree = malloc(sizeof(**tree));
1646 			if (*tree == NULL) {
1647 				err = got_error_from_errno("malloc");
1648 				break;
1649 			}
1650 			(*tree)->entries = calloc(itree->nentries,
1651 			    sizeof(struct got_tree_entry));
1652 			if ((*tree)->entries == NULL) {
1653 				err = got_error_from_errno("malloc");
1654 				free(*tree);
1655 				*tree = NULL;
1656 				break;
1657 			}
1658 			(*tree)->nentries = itree->nentries;
1659 			(*tree)->refcnt = 0;
1660 			break;
1661 		case GOT_IMSG_TREE_ENTRIES:
1662 			/* This message should be preceeded by GOT_IMSG_TREE. */
1663 			if (*tree == NULL) {
1664 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1665 				break;
1666 			}
1667 			err = recv_tree_entries(imsg.data, datalen,
1668 			    *tree, &nentries);
1669 			break;
1670 		default:
1671 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1672 			break;
1673 		}
1674 
1675 		imsg_free(&imsg);
1676 		if (err)
1677 			break;
1678 	}
1679 done:
1680 	if (*tree && (*tree)->nentries != nentries) {
1681 		if (err == NULL)
1682 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1683 		got_object_tree_close(*tree);
1684 		*tree = NULL;
1685 	}
1686 
1687 	return err;
1688 }
1689 
1690 const struct got_error *
1691 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1692     const uint8_t *data)
1693 {
1694 	struct got_imsg_blob iblob;
1695 
1696 	memset(&iblob, 0, sizeof(iblob));
1697 	iblob.size = size;
1698 	iblob.hdrlen = hdrlen;
1699 
1700 	if (data) {
1701 		uint8_t *buf;
1702 
1703 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1704 			return got_error(GOT_ERR_NO_SPACE);
1705 
1706 		buf = malloc(sizeof(iblob) + size);
1707 		if (buf == NULL)
1708 			return got_error_from_errno("malloc");
1709 
1710 		memcpy(buf, &iblob, sizeof(iblob));
1711 		memcpy(buf + sizeof(iblob), data, size);
1712 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1713 		    sizeof(iblob) + size) == -1) {
1714 			free(buf);
1715 			return got_error_from_errno("imsg_compose BLOB");
1716 		}
1717 		free(buf);
1718 	} else {
1719 		/* Data has already been written to file descriptor. */
1720 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1721 		    sizeof(iblob)) == -1)
1722 			return got_error_from_errno("imsg_compose BLOB");
1723 	}
1724 
1725 
1726 	return flush_imsg(ibuf);
1727 }
1728 
1729 const struct got_error *
1730 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1731     struct imsgbuf *ibuf)
1732 {
1733 	const struct got_error *err = NULL;
1734 	struct imsg imsg;
1735 	struct got_imsg_blob *iblob;
1736 	size_t datalen;
1737 
1738 	*outbuf = NULL;
1739 
1740 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1741 	if (err)
1742 		return err;
1743 
1744 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1745 
1746 	switch (imsg.hdr.type) {
1747 	case GOT_IMSG_BLOB:
1748 		if (datalen < sizeof(*iblob)) {
1749 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1750 			break;
1751 		}
1752 		iblob = imsg.data;
1753 		*size = iblob->size;
1754 		*hdrlen = iblob->hdrlen;
1755 
1756 		if (datalen == sizeof(*iblob)) {
1757 			/* Data has been written to file descriptor. */
1758 			break;
1759 		}
1760 
1761 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX ||
1762 		    *size > datalen + sizeof(*iblob)) {
1763 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1764 			break;
1765 		}
1766 
1767 		*outbuf = malloc(*size);
1768 		if (*outbuf == NULL) {
1769 			err = got_error_from_errno("malloc");
1770 			break;
1771 		}
1772 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1773 		break;
1774 	default:
1775 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1776 		break;
1777 	}
1778 
1779 	imsg_free(&imsg);
1780 
1781 	return err;
1782 }
1783 
1784 static const struct got_error *
1785 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1786 {
1787 	const struct got_error *err = NULL;
1788 	size_t offset, remain;
1789 
1790 	offset = 0;
1791 	remain = tagmsg_len;
1792 	while (remain > 0) {
1793 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1794 
1795 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1796 		    tag->tagmsg + offset, n) == -1) {
1797 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1798 			break;
1799 		}
1800 
1801 		err = flush_imsg(ibuf);
1802 		if (err)
1803 			break;
1804 
1805 		offset += n;
1806 		remain -= n;
1807 	}
1808 
1809 	return err;
1810 }
1811 
1812 const struct got_error *
1813 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1814 {
1815 	const struct got_error *err = NULL;
1816 	struct got_imsg_tag_object *itag;
1817 	uint8_t *buf;
1818 	size_t len, total;
1819 	size_t tag_len = strlen(tag->tag);
1820 	size_t tagger_len = strlen(tag->tagger);
1821 	size_t tagmsg_len = strlen(tag->tagmsg);
1822 
1823 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1824 
1825 	buf = malloc(total);
1826 	if (buf == NULL)
1827 		return got_error_from_errno("malloc");
1828 
1829 	itag = (struct got_imsg_tag_object *)buf;
1830 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1831 	itag->obj_type = tag->obj_type;
1832 	itag->tag_len = tag_len;
1833 	itag->tagger_len = tagger_len;
1834 	itag->tagger_time = tag->tagger_time;
1835 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1836 	itag->tagmsg_len = tagmsg_len;
1837 
1838 	len = sizeof(*itag);
1839 	memcpy(buf + len, tag->tag, tag_len);
1840 	len += tag_len;
1841 	memcpy(buf + len, tag->tagger, tagger_len);
1842 	len += tagger_len;
1843 
1844 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1845 		err = got_error_from_errno("imsg_compose TAG");
1846 		goto done;
1847 	}
1848 
1849 	if (tagmsg_len == 0 ||
1850 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1851 		err = flush_imsg(ibuf);
1852 		if (err)
1853 			goto done;
1854 	}
1855 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1856 done:
1857 	free(buf);
1858 	return err;
1859 }
1860 
1861 const struct got_error *
1862 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1863 {
1864 	const struct got_error *err = NULL;
1865 	struct imsg imsg;
1866 	struct got_imsg_tag_object *itag;
1867 	size_t len, datalen;
1868 	const size_t min_datalen =
1869 	    MIN(sizeof(struct got_imsg_error),
1870 	    sizeof(struct got_imsg_tag_object));
1871 
1872 	*tag = NULL;
1873 
1874 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1875 	if (err)
1876 		return err;
1877 
1878 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1879 	len = 0;
1880 
1881 	switch (imsg.hdr.type) {
1882 	case GOT_IMSG_TAG:
1883 		if (datalen < sizeof(*itag)) {
1884 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1885 			break;
1886 		}
1887 		itag = imsg.data;
1888 		if (datalen != sizeof(*itag) + itag->tag_len +
1889 		    itag->tagger_len) {
1890 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1891 			break;
1892 		}
1893 		len += sizeof(*itag);
1894 
1895 		*tag = calloc(1, sizeof(**tag));
1896 		if (*tag == NULL) {
1897 			err = got_error_from_errno("calloc");
1898 			break;
1899 		}
1900 
1901 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1902 
1903 		(*tag)->tag = strndup(imsg.data + len, itag->tag_len);
1904 		if ((*tag)->tag == NULL) {
1905 			err = got_error_from_errno("strndup");
1906 			break;
1907 		}
1908 		len += itag->tag_len;
1909 
1910 		(*tag)->obj_type = itag->obj_type;
1911 		(*tag)->tagger_time = itag->tagger_time;
1912 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1913 
1914 		(*tag)->tagger = strndup(imsg.data + len, itag->tagger_len);
1915 		if ((*tag)->tagger == NULL) {
1916 			err = got_error_from_errno("strndup");
1917 			break;
1918 		}
1919 		len += itag->tagger_len;
1920 
1921 		if (itag->tagmsg_len == 0) {
1922 			(*tag)->tagmsg = strdup("");
1923 			if ((*tag)->tagmsg == NULL) {
1924 				err = got_error_from_errno("strdup");
1925 				break;
1926 			}
1927 		} else {
1928 			size_t offset = 0, remain = itag->tagmsg_len;
1929 
1930 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1931 			if ((*tag)->tagmsg == NULL) {
1932 				err = got_error_from_errno("malloc");
1933 				break;
1934 			}
1935 			while (remain > 0) {
1936 				struct imsg imsg_log;
1937 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1938 				    remain);
1939 
1940 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1941 				if (err)
1942 					return err;
1943 
1944 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1945 					return got_error(GOT_ERR_PRIVSEP_MSG);
1946 
1947 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1948 				    n);
1949 				imsg_free(&imsg_log);
1950 				offset += n;
1951 				remain -= n;
1952 			}
1953 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1954 		}
1955 
1956 		break;
1957 	default:
1958 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1959 		break;
1960 	}
1961 
1962 	imsg_free(&imsg);
1963 
1964 	return err;
1965 }
1966 
1967 const struct got_error *
1968 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1969     struct got_packidx *packidx)
1970 {
1971 	const struct got_error *err = NULL;
1972 	struct got_imsg_packidx ipackidx;
1973 	struct got_imsg_pack ipack;
1974 	int fd;
1975 
1976 	memset(&ipackidx, 0, sizeof(ipackidx));
1977 	memset(&ipack, 0, sizeof(ipack));
1978 
1979 	ipackidx.len = packidx->len;
1980 	ipackidx.packfile_size = pack->filesize;
1981 	fd = dup(packidx->fd);
1982 	if (fd == -1)
1983 		return got_error_from_errno("dup");
1984 
1985 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
1986 	    sizeof(ipackidx)) == -1) {
1987 		err = got_error_from_errno("imsg_compose PACKIDX");
1988 		close(fd);
1989 		return err;
1990 	}
1991 
1992 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
1993 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
1994 		return got_error(GOT_ERR_NO_SPACE);
1995 	ipack.filesize = pack->filesize;
1996 
1997 	fd = dup(pack->fd);
1998 	if (fd == -1)
1999 		return got_error_from_errno("dup");
2000 
2001 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
2002 	    == -1) {
2003 		err = got_error_from_errno("imsg_compose PACK");
2004 		close(fd);
2005 		return err;
2006 	}
2007 
2008 	return flush_imsg(ibuf);
2009 }
2010 
2011 const struct got_error *
2012 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
2013     struct got_object_id *id)
2014 {
2015 	struct got_imsg_packed_object iobj;
2016 
2017 	memset(&iobj, 0, sizeof(iobj));
2018 	iobj.idx = idx;
2019 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2020 
2021 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
2022 	    &iobj, sizeof(iobj)) == -1)
2023 		return got_error_from_errno("imsg_compose "
2024 		    "PACKED_OBJECT_REQUEST");
2025 
2026 	return flush_imsg(ibuf);
2027 }
2028 
2029 const struct got_error *
2030 got_privsep_send_packed_raw_obj_req(struct imsgbuf *ibuf, int idx,
2031     struct got_object_id *id)
2032 {
2033 	struct got_imsg_packed_object iobj;
2034 
2035 	memset(&iobj, 0, sizeof(iobj));
2036 	iobj.idx = idx;
2037 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2038 
2039 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_RAW_OBJECT_REQUEST, 0, 0, -1,
2040 	    &iobj, sizeof(iobj)) == -1)
2041 		return got_error_from_errno("imsg_compose "
2042 		    "PACKED_OBJECT_REQUEST");
2043 
2044 	return flush_imsg(ibuf);
2045 }
2046 
2047 const struct got_error *
2048 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
2049 {
2050 	const struct got_error *err = NULL;
2051 
2052 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
2053 	    NULL, 0) == -1) {
2054 		err = got_error_from_errno("imsg_compose "
2055 		    "GITCONFIG_PARSE_REQUEST");
2056 		close(fd);
2057 		return err;
2058 	}
2059 
2060 	return flush_imsg(ibuf);
2061 }
2062 
2063 const struct got_error *
2064 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
2065 {
2066 	if (imsg_compose(ibuf,
2067 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
2068 	    NULL, 0) == -1)
2069 		return got_error_from_errno("imsg_compose "
2070 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
2071 
2072 	return flush_imsg(ibuf);
2073 }
2074 
2075 const struct got_error *
2076 got_privsep_send_gitconfig_repository_extensions_req(struct imsgbuf *ibuf)
2077 {
2078 	if (imsg_compose(ibuf,
2079 	    GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST, 0, 0, -1,
2080 	    NULL, 0) == -1)
2081 		return got_error_from_errno("imsg_compose "
2082 		    "GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST");
2083 
2084 	return flush_imsg(ibuf);
2085 }
2086 
2087 
2088 const struct got_error *
2089 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
2090 {
2091 	if (imsg_compose(ibuf,
2092 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
2093 		return got_error_from_errno("imsg_compose "
2094 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
2095 
2096 	return flush_imsg(ibuf);
2097 }
2098 
2099 const struct got_error *
2100 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
2101 {
2102 	if (imsg_compose(ibuf,
2103 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
2104 		return got_error_from_errno("imsg_compose "
2105 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
2106 
2107 	return flush_imsg(ibuf);
2108 }
2109 
2110 const struct got_error *
2111 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
2112 {
2113 	if (imsg_compose(ibuf,
2114 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2115 		return got_error_from_errno("imsg_compose "
2116 		    "GITCONFIG_REMOTE_REQUEST");
2117 
2118 	return flush_imsg(ibuf);
2119 }
2120 
2121 const struct got_error *
2122 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
2123 {
2124 	if (imsg_compose(ibuf,
2125 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
2126 		return got_error_from_errno("imsg_compose "
2127 		    "GITCONFIG_OWNER_REQUEST");
2128 
2129 	return flush_imsg(ibuf);
2130 }
2131 
2132 const struct got_error *
2133 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
2134 {
2135 	const struct got_error *err = NULL;
2136 	struct imsg imsg;
2137 	size_t datalen;
2138 
2139 	*str = NULL;
2140 
2141 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2142 	if (err)
2143 		return err;
2144 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2145 
2146 	switch (imsg.hdr.type) {
2147 	case GOT_IMSG_GITCONFIG_STR_VAL:
2148 		if (datalen == 0)
2149 			break;
2150 		/* datalen does not include terminating \0 */
2151 		*str = malloc(datalen + 1);
2152 		if (*str == NULL) {
2153 			err = got_error_from_errno("malloc");
2154 			break;
2155 		}
2156 		memcpy(*str, imsg.data, datalen);
2157 		(*str)[datalen] = '\0';
2158 		break;
2159 	default:
2160 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2161 		break;
2162 	}
2163 
2164 	imsg_free(&imsg);
2165 	return err;
2166 }
2167 
2168 const struct got_error *
2169 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
2170 {
2171 	const struct got_error *err = NULL;
2172 	struct imsg imsg;
2173 	size_t datalen;
2174 	const size_t min_datalen =
2175 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
2176 
2177 	*val = 0;
2178 
2179 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2180 	if (err)
2181 		return err;
2182 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2183 
2184 	switch (imsg.hdr.type) {
2185 	case GOT_IMSG_GITCONFIG_INT_VAL:
2186 		if (datalen != sizeof(*val)) {
2187 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2188 			break;
2189 		}
2190 		memcpy(val, imsg.data, sizeof(*val));
2191 		break;
2192 	default:
2193 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2194 		break;
2195 	}
2196 
2197 	imsg_free(&imsg);
2198 	return err;
2199 }
2200 
2201 static void
2202 free_remote_data(struct got_remote_repo *remote)
2203 {
2204 	int i;
2205 
2206 	free(remote->name);
2207 	free(remote->fetch_url);
2208 	free(remote->send_url);
2209 	for (i = 0; i < remote->nfetch_branches; i++)
2210 		free(remote->fetch_branches[i]);
2211 	free(remote->fetch_branches);
2212 	for (i = 0; i < remote->nsend_branches; i++)
2213 		free(remote->send_branches[i]);
2214 	free(remote->send_branches);
2215 	for (i = 0; i < remote->nfetch_refs; i++)
2216 		free(remote->fetch_refs[i]);
2217 	free(remote->fetch_refs);
2218 }
2219 
2220 const struct got_error *
2221 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
2222     int *nremotes, struct imsgbuf *ibuf)
2223 {
2224 	const struct got_error *err = NULL;
2225 	struct imsg imsg;
2226 	size_t datalen;
2227 	struct got_imsg_remotes iremotes;
2228 	struct got_imsg_remote iremote;
2229 
2230 	*remotes = NULL;
2231 	*nremotes = 0;
2232 	iremotes.nremotes = 0;
2233 
2234 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
2235 	if (err)
2236 		return err;
2237 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2238 
2239 	switch (imsg.hdr.type) {
2240 	case GOT_IMSG_GITCONFIG_REMOTES:
2241 		if (datalen != sizeof(iremotes)) {
2242 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2243 			break;
2244 		}
2245 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2246 		if (iremotes.nremotes == 0) {
2247 			imsg_free(&imsg);
2248 			return NULL;
2249 		}
2250 		break;
2251 	default:
2252 		imsg_free(&imsg);
2253 		return got_error(GOT_ERR_PRIVSEP_MSG);
2254 	}
2255 
2256 	imsg_free(&imsg);
2257 
2258 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2259 	if (*remotes == NULL)
2260 		return got_error_from_errno("recallocarray");
2261 
2262 	while (*nremotes < iremotes.nremotes) {
2263 		struct got_remote_repo *remote;
2264 
2265 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
2266 		if (err)
2267 			break;
2268 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2269 
2270 		switch (imsg.hdr.type) {
2271 		case GOT_IMSG_GITCONFIG_REMOTE:
2272 			remote = &(*remotes)[*nremotes];
2273 			memset(remote, 0, sizeof(*remote));
2274 			if (datalen < sizeof(iremote)) {
2275 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2276 				break;
2277 			}
2278 			memcpy(&iremote, imsg.data, sizeof(iremote));
2279 			if (iremote.name_len == 0 ||
2280 			    iremote.fetch_url_len == 0 ||
2281 			    iremote.send_url_len == 0 ||
2282 			    (sizeof(iremote) + iremote.name_len +
2283 			    iremote.fetch_url_len + iremote.send_url_len) > datalen) {
2284 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2285 				break;
2286 			}
2287 			remote->name = strndup(imsg.data + sizeof(iremote),
2288 			    iremote.name_len);
2289 			if (remote->name == NULL) {
2290 				err = got_error_from_errno("strndup");
2291 				break;
2292 			}
2293 			remote->fetch_url = strndup(imsg.data + sizeof(iremote) +
2294 			    iremote.name_len, iremote.fetch_url_len);
2295 			if (remote->fetch_url == NULL) {
2296 				err = got_error_from_errno("strndup");
2297 				free_remote_data(remote);
2298 				break;
2299 			}
2300 			remote->send_url = strndup(imsg.data + sizeof(iremote) +
2301 			    iremote.name_len + iremote.fetch_url_len,
2302 			    iremote.send_url_len);
2303 			if (remote->send_url == NULL) {
2304 				err = got_error_from_errno("strndup");
2305 				free_remote_data(remote);
2306 				break;
2307 			}
2308 			remote->mirror_references = iremote.mirror_references;
2309 			remote->fetch_all_branches = iremote.fetch_all_branches;
2310 			remote->nfetch_branches = 0;
2311 			remote->fetch_branches = NULL;
2312 			remote->nsend_branches = 0;
2313 			remote->send_branches = NULL;
2314 			remote->nfetch_refs = 0;
2315 			remote->fetch_refs = NULL;
2316 			(*nremotes)++;
2317 			break;
2318 		default:
2319 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2320 			break;
2321 		}
2322 
2323 		imsg_free(&imsg);
2324 		if (err)
2325 			break;
2326 	}
2327 
2328 	if (err) {
2329 		int i;
2330 		for (i = 0; i < *nremotes; i++)
2331 			free_remote_data(&(*remotes)[i]);
2332 		free(*remotes);
2333 		*remotes = NULL;
2334 		*nremotes = 0;
2335 	}
2336 	return err;
2337 }
2338 
2339 const struct got_error *
2340 got_privsep_send_gotconfig_parse_req(struct imsgbuf *ibuf, int fd)
2341 {
2342 	const struct got_error *err = NULL;
2343 
2344 	if (imsg_compose(ibuf, GOT_IMSG_GOTCONFIG_PARSE_REQUEST, 0, 0, fd,
2345 	    NULL, 0) == -1) {
2346 		err = got_error_from_errno("imsg_compose "
2347 		    "GOTCONFIG_PARSE_REQUEST");
2348 		close(fd);
2349 		return err;
2350 	}
2351 
2352 	return flush_imsg(ibuf);
2353 }
2354 
2355 const struct got_error *
2356 got_privsep_send_gotconfig_author_req(struct imsgbuf *ibuf)
2357 {
2358 	if (imsg_compose(ibuf,
2359 	    GOT_IMSG_GOTCONFIG_AUTHOR_REQUEST, 0, 0, -1, NULL, 0) == -1)
2360 		return got_error_from_errno("imsg_compose "
2361 		    "GOTCONFIG_AUTHOR_REQUEST");
2362 
2363 	return flush_imsg(ibuf);
2364 }
2365 
2366 const struct got_error *
2367 got_privsep_send_gotconfig_remotes_req(struct imsgbuf *ibuf)
2368 {
2369 	if (imsg_compose(ibuf,
2370 	    GOT_IMSG_GOTCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2371 		return got_error_from_errno("imsg_compose "
2372 		    "GOTCONFIG_REMOTE_REQUEST");
2373 
2374 	return flush_imsg(ibuf);
2375 }
2376 
2377 const struct got_error *
2378 got_privsep_recv_gotconfig_str(char **str, struct imsgbuf *ibuf)
2379 {
2380 	const struct got_error *err = NULL;
2381 	struct imsg imsg;
2382 	size_t datalen;
2383 
2384 	*str = NULL;
2385 
2386 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2387 	if (err)
2388 		return err;
2389 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2390 
2391 	switch (imsg.hdr.type) {
2392 	case GOT_IMSG_ERROR:
2393 		err = recv_imsg_error(&imsg, datalen);
2394 		break;
2395 	case GOT_IMSG_GOTCONFIG_STR_VAL:
2396 		if (datalen == 0)
2397 			break;
2398 		/* datalen does not include terminating \0 */
2399 		*str = malloc(datalen + 1);
2400 		if (*str == NULL) {
2401 			err = got_error_from_errno("malloc");
2402 			break;
2403 		}
2404 		memcpy(*str, imsg.data, datalen);
2405 		(*str)[datalen] = '\0';
2406 		break;
2407 	default:
2408 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2409 		break;
2410 	}
2411 
2412 	imsg_free(&imsg);
2413 	return err;
2414 }
2415 
2416 const struct got_error *
2417 got_privsep_recv_gotconfig_remotes(struct got_remote_repo **remotes,
2418     int *nremotes, struct imsgbuf *ibuf)
2419 {
2420 	const struct got_error *err = NULL;
2421 	struct imsg imsg;
2422 	size_t datalen;
2423 	struct got_imsg_remotes iremotes;
2424 	struct got_imsg_remote iremote;
2425 	const size_t min_datalen =
2426 	    MIN(sizeof(struct got_imsg_error), sizeof(iremotes));
2427 
2428 	*remotes = NULL;
2429 	*nremotes = 0;
2430 	iremotes.nremotes = 0;
2431 
2432 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2433 	if (err)
2434 		return err;
2435 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2436 
2437 	switch (imsg.hdr.type) {
2438 	case GOT_IMSG_ERROR:
2439 		err = recv_imsg_error(&imsg, datalen);
2440 		break;
2441 	case GOT_IMSG_GOTCONFIG_REMOTES:
2442 		if (datalen != sizeof(iremotes)) {
2443 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2444 			break;
2445 		}
2446 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2447 		if (iremotes.nremotes < 0) {
2448 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2449 			break;
2450 		}
2451 		if (iremotes.nremotes == 0) {
2452 			imsg_free(&imsg);
2453 			return NULL;
2454 		}
2455 		break;
2456 	default:
2457 		imsg_free(&imsg);
2458 		return got_error(GOT_ERR_PRIVSEP_MSG);
2459 	}
2460 
2461 	imsg_free(&imsg);
2462 
2463 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2464 	if (*remotes == NULL)
2465 		return got_error_from_errno("recallocarray");
2466 
2467 	while (*nremotes < iremotes.nremotes) {
2468 		struct got_remote_repo *remote;
2469 		const size_t min_datalen =
2470 		    MIN(sizeof(struct got_imsg_error), sizeof(iremote));
2471 		int i;
2472 
2473 		err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2474 		if (err)
2475 			break;
2476 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2477 
2478 		switch (imsg.hdr.type) {
2479 		case GOT_IMSG_ERROR:
2480 			err = recv_imsg_error(&imsg, datalen);
2481 			break;
2482 		case GOT_IMSG_GOTCONFIG_REMOTE:
2483 			remote = &(*remotes)[*nremotes];
2484 			memset(remote, 0, sizeof(*remote));
2485 			if (datalen < sizeof(iremote)) {
2486 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2487 				break;
2488 			}
2489 			memcpy(&iremote, imsg.data, sizeof(iremote));
2490 			if (iremote.name_len == 0 ||
2491 			    (iremote.fetch_url_len == 0 &&
2492 			    iremote.send_url_len == 0) ||
2493 			    (sizeof(iremote) + iremote.name_len +
2494 			    iremote.fetch_url_len + iremote.send_url_len) >
2495 			    datalen) {
2496 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2497 				break;
2498 			}
2499 			remote->name = strndup(imsg.data + sizeof(iremote),
2500 			    iremote.name_len);
2501 			if (remote->name == NULL) {
2502 				err = got_error_from_errno("strndup");
2503 				break;
2504 			}
2505 			remote->fetch_url = strndup(imsg.data +
2506 			    sizeof(iremote) + iremote.name_len,
2507 			    iremote.fetch_url_len);
2508 			if (remote->fetch_url == NULL) {
2509 				err = got_error_from_errno("strndup");
2510 				free_remote_data(remote);
2511 				break;
2512 			}
2513 			remote->send_url = strndup(imsg.data +
2514 			    sizeof(iremote) + iremote.name_len +
2515 			    iremote.fetch_url_len, iremote.send_url_len);
2516 			if (remote->send_url == NULL) {
2517 				err = got_error_from_errno("strndup");
2518 				free_remote_data(remote);
2519 				break;
2520 			}
2521 			remote->mirror_references = iremote.mirror_references;
2522 			remote->fetch_all_branches = iremote.fetch_all_branches;
2523 			if (iremote.nfetch_branches > 0) {
2524 				remote->fetch_branches = recallocarray(NULL, 0,
2525 				    iremote.nfetch_branches, sizeof(char *));
2526 				if (remote->fetch_branches == NULL) {
2527 					err = got_error_from_errno("calloc");
2528 					free_remote_data(remote);
2529 					break;
2530 				}
2531 			}
2532 			remote->nfetch_branches = 0;
2533 			for (i = 0; i < iremote.nfetch_branches; i++) {
2534 				char *branch;
2535 				err = got_privsep_recv_gotconfig_str(&branch,
2536 				    ibuf);
2537 				if (err) {
2538 					free_remote_data(remote);
2539 					goto done;
2540 				}
2541 				remote->fetch_branches[i] = branch;
2542 				remote->nfetch_branches++;
2543 			}
2544 			if (iremote.nsend_branches > 0) {
2545 				remote->send_branches = recallocarray(NULL, 0,
2546 				    iremote.nsend_branches, sizeof(char *));
2547 				if (remote->send_branches == NULL) {
2548 					err = got_error_from_errno("calloc");
2549 					free_remote_data(remote);
2550 					break;
2551 				}
2552 			}
2553 			remote->nsend_branches = 0;
2554 			for (i = 0; i < iremote.nsend_branches; i++) {
2555 				char *branch;
2556 				err = got_privsep_recv_gotconfig_str(&branch,
2557 				    ibuf);
2558 				if (err) {
2559 					free_remote_data(remote);
2560 					goto done;
2561 				}
2562 				remote->send_branches[i] = branch;
2563 				remote->nsend_branches++;
2564 			}
2565 			if (iremote.nfetch_refs > 0) {
2566 				remote->fetch_refs = recallocarray(NULL, 0,
2567 				    iremote.nfetch_refs, sizeof(char *));
2568 				if (remote->fetch_refs == NULL) {
2569 					err = got_error_from_errno("calloc");
2570 					free_remote_data(remote);
2571 					break;
2572 				}
2573 			}
2574 			remote->nfetch_refs = 0;
2575 			for (i = 0; i < iremote.nfetch_refs; i++) {
2576 				char *ref;
2577 				err = got_privsep_recv_gotconfig_str(&ref,
2578 				    ibuf);
2579 				if (err) {
2580 					free_remote_data(remote);
2581 					goto done;
2582 				}
2583 				remote->fetch_refs[i] = ref;
2584 				remote->nfetch_refs++;
2585 			}
2586 			(*nremotes)++;
2587 			break;
2588 		default:
2589 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2590 			break;
2591 		}
2592 
2593 		imsg_free(&imsg);
2594 		if (err)
2595 			break;
2596 	}
2597 done:
2598 	if (err) {
2599 		int i;
2600 		for (i = 0; i < *nremotes; i++)
2601 			free_remote_data(&(*remotes)[i]);
2602 		free(*remotes);
2603 		*remotes = NULL;
2604 		*nremotes = 0;
2605 	}
2606 	return err;
2607 }
2608 
2609 const struct got_error *
2610 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
2611     struct got_object_id *id, int idx, const char *path)
2612 {
2613 	struct ibuf *wbuf;
2614 	size_t path_len = strlen(path) + 1;
2615 
2616 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
2617 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
2618 	if (wbuf == NULL)
2619 		return got_error_from_errno(
2620 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
2621 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1)
2622 		return got_error_from_errno("imsg_add "
2623 		    "COMMIT_TRAVERSAL_REQUEST");
2624 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1)
2625 		return got_error_from_errno("imsg_add "
2626 		    "COMMIT_TRAVERSAL_REQUEST");
2627 	if (imsg_add(wbuf, path, path_len) == -1)
2628 		return got_error_from_errno("imsg_add "
2629 		    "COMMIT_TRAVERSAL_REQUEST");
2630 
2631 	wbuf->fd = -1;
2632 	imsg_close(ibuf, wbuf);
2633 
2634 	return flush_imsg(ibuf);
2635 }
2636 
2637 const struct got_error *
2638 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
2639     struct got_object_id **changed_commit_id,
2640     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
2641 {
2642 	const struct got_error *err = NULL;
2643 	struct imsg imsg;
2644 	struct got_imsg_traversed_commits *icommits;
2645 	size_t datalen;
2646 	int i, done = 0;
2647 
2648 	*changed_commit = NULL;
2649 	*changed_commit_id = NULL;
2650 
2651 	while (!done) {
2652 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2653 		if (err)
2654 			return err;
2655 
2656 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2657 		switch (imsg.hdr.type) {
2658 		case GOT_IMSG_TRAVERSED_COMMITS:
2659 			icommits = imsg.data;
2660 			if (datalen != sizeof(*icommits) +
2661 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
2662 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2663 				break;
2664 			}
2665 			for (i = 0; i < icommits->ncommits; i++) {
2666 				struct got_object_qid *qid;
2667 				uint8_t *sha1 = (uint8_t *)imsg.data +
2668 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
2669 				err = got_object_qid_alloc_partial(&qid);
2670 				if (err)
2671 					break;
2672 				memcpy(qid->id.sha1, sha1, SHA1_DIGEST_LENGTH);
2673 				STAILQ_INSERT_TAIL(commit_ids, qid, entry);
2674 
2675 				/* The last commit may contain a change. */
2676 				if (i == icommits->ncommits - 1) {
2677 					*changed_commit_id =
2678 					    got_object_id_dup(&qid->id);
2679 					if (*changed_commit_id == NULL) {
2680 						err = got_error_from_errno(
2681 						    "got_object_id_dup");
2682 						break;
2683 					}
2684 				}
2685 			}
2686 			break;
2687 		case GOT_IMSG_COMMIT:
2688 			if (*changed_commit_id == NULL) {
2689 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2690 				break;
2691 			}
2692 			err = get_commit_from_imsg(changed_commit, &imsg,
2693 			    datalen, ibuf);
2694 			break;
2695 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
2696 			done = 1;
2697 			break;
2698 		default:
2699 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2700 			break;
2701 		}
2702 
2703 		imsg_free(&imsg);
2704 		if (err)
2705 			break;
2706 	}
2707 
2708 	if (err)
2709 		got_object_id_queue_free(commit_ids);
2710 	return err;
2711 }
2712 
2713 const struct got_error *
2714 got_privsep_send_enumerated_tree(size_t *totlen, struct imsgbuf *ibuf,
2715     struct got_object_id *tree_id, const char *path,
2716     struct got_parsed_tree_entry *entries, int nentries)
2717 {
2718 	const struct got_error *err = NULL;
2719 	struct ibuf *wbuf;
2720 	size_t path_len = strlen(path);
2721 	size_t msglen;
2722 
2723 	msglen = sizeof(struct got_imsg_enumerated_tree) + path_len;
2724 	wbuf = imsg_create(ibuf, GOT_IMSG_ENUMERATED_TREE, 0, 0, msglen);
2725 	if (wbuf == NULL)
2726 		return got_error_from_errno("imsg_create ENUMERATED_TREE");
2727 
2728 	if (imsg_add(wbuf, tree_id->sha1, SHA1_DIGEST_LENGTH) == -1)
2729 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2730 	if (imsg_add(wbuf, &nentries, sizeof(nentries)) == -1)
2731 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2732 	if (imsg_add(wbuf, path, path_len) == -1)
2733 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2734 
2735 	wbuf->fd = -1;
2736 	imsg_close(ibuf, wbuf);
2737 
2738 	if (entries) {
2739 		err = send_tree_entries(ibuf, entries, nentries);
2740 		if (err)
2741 			return err;
2742 	}
2743 
2744 	return flush_imsg(ibuf);
2745 }
2746 
2747 const struct got_error *
2748 got_privsep_send_object_enumeration_request(struct imsgbuf *ibuf)
2749 {
2750 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_REQUEST,
2751 	    0, 0, -1, NULL, 0) == -1)
2752 		return got_error_from_errno("imsg_compose "
2753 		    "OBJECT_ENUMERATION_REQUEST");
2754 
2755 	return flush_imsg(ibuf);
2756 }
2757 
2758 const struct got_error *
2759 got_privsep_send_object_enumeration_done(struct imsgbuf *ibuf)
2760 {
2761 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_DONE,
2762 	    0, 0, -1, NULL, 0) == -1)
2763 		return got_error_from_errno("imsg_compose "
2764 		    "OBJECT_ENUMERATION_DONE");
2765 
2766 	return flush_imsg(ibuf);
2767 }
2768 
2769 const struct got_error *
2770 got_privsep_send_object_enumeration_incomplete(struct imsgbuf *ibuf)
2771 {
2772 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_INCOMPLETE,
2773 	    0, 0, -1, NULL, 0) == -1)
2774 		return got_error_from_errno("imsg_compose "
2775 		    "OBJECT_ENUMERATION_INCOMPLETE");
2776 
2777 	return flush_imsg(ibuf);
2778 }
2779 
2780 const struct got_error *
2781 got_privsep_send_enumerated_commit(struct imsgbuf *ibuf,
2782     struct got_object_id *id, time_t mtime)
2783 {
2784 	struct ibuf *wbuf;
2785 
2786 	wbuf = imsg_create(ibuf, GOT_IMSG_ENUMERATED_COMMIT, 0, 0,
2787 	    sizeof(struct got_imsg_enumerated_commit) + SHA1_DIGEST_LENGTH);
2788 	if (wbuf == NULL)
2789 		return got_error_from_errno("imsg_create ENUMERATED_COMMIT");
2790 
2791 	/* Keep in sync with struct got_imsg_enumerated_commit! */
2792 	if (imsg_add(wbuf, id, SHA1_DIGEST_LENGTH) == -1)
2793 		return got_error_from_errno("imsg_add ENUMERATED_COMMIT");
2794 	if (imsg_add(wbuf, &mtime, sizeof(mtime)) == -1)
2795 		return got_error_from_errno("imsg_add ENUMERATED_COMMIT");
2796 
2797 	wbuf->fd = -1;
2798 	imsg_close(ibuf, wbuf);
2799 	/* Don't flush yet, tree entries or ENUMERATION_DONE will follow. */
2800 	return NULL;
2801 }
2802 
2803 const struct got_error *
2804 got_privsep_recv_enumerated_objects(int *found_all_objects,
2805     struct imsgbuf *ibuf,
2806     got_object_enumerate_commit_cb cb_commit,
2807     got_object_enumerate_tree_cb cb_tree, void *cb_arg,
2808     struct got_repository *repo)
2809 {
2810 	const struct got_error *err = NULL;
2811 	struct imsg imsg;
2812 	struct got_imsg_enumerated_commit *icommit = NULL;
2813 	struct got_object_id commit_id;
2814 	int have_commit = 0;
2815 	time_t mtime = 0;
2816 	struct got_tree_object tree;
2817 	struct got_imsg_enumerated_tree *itree;
2818 	struct got_object_id tree_id;
2819 	char *path = NULL, *canon_path = NULL;
2820 	size_t datalen, path_len;
2821 	int nentries = -1;
2822 	int done = 0;
2823 
2824 	*found_all_objects = 0;
2825 	memset(&tree, 0, sizeof(tree));
2826 
2827 	while (!done) {
2828 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2829 		if (err)
2830 			break;
2831 
2832 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2833 		switch (imsg.hdr.type) {
2834 		case GOT_IMSG_ENUMERATED_COMMIT:
2835 			if (have_commit && nentries != -1) {
2836 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2837 				break;
2838 			}
2839 			if (datalen != sizeof(*icommit)) {
2840 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2841 				break;
2842 			}
2843 			icommit = (struct got_imsg_enumerated_commit *)imsg.data;
2844 			memcpy(commit_id.sha1, icommit->id, SHA1_DIGEST_LENGTH);
2845 			mtime = icommit->mtime;
2846 			have_commit = 1;
2847 			break;
2848 		case GOT_IMSG_ENUMERATED_TREE:
2849 			/* Should be preceeded by GOT_IMSG_ENUMERATED_COMMIT. */
2850 			if (!have_commit) {
2851 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2852 				break;
2853 			}
2854 			if (datalen < sizeof(*itree)) {
2855 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2856 				break;
2857 			}
2858 			itree = imsg.data;
2859 			path_len = datalen - sizeof(*itree);
2860 			if (path_len == 0) {
2861 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2862 				break;
2863 			}
2864 			memcpy(tree_id.sha1, itree->id, sizeof(tree_id.sha1));
2865 			free(path);
2866 			path = malloc(path_len + 1);
2867 			if (path == NULL) {
2868 				err = got_error_from_errno("malloc");
2869 				break;
2870 			}
2871 			free(canon_path);
2872 			canon_path = malloc(path_len + 1);
2873 			if (canon_path == NULL) {
2874 				err = got_error_from_errno("malloc");
2875 				break;
2876 			}
2877 			memcpy(path, (uint8_t *)imsg.data + sizeof(*itree),
2878 			    path_len);
2879 			path[path_len] = '\0';
2880 			if (!got_path_is_absolute(path)) {
2881 				err = got_error(GOT_ERR_BAD_PATH);
2882 				break;
2883 			}
2884 			if (got_path_is_root_dir(path)) {
2885 				/* XXX check what got_canonpath() does wrong */
2886 				canon_path[0] = '/';
2887 				canon_path[1] = '\0';
2888 			} else {
2889 				err = got_canonpath(path, canon_path,
2890 				    path_len + 1);
2891 				if (err)
2892 					break;
2893 			}
2894 			if (strcmp(path, canon_path) != 0) {
2895 				err = got_error(GOT_ERR_BAD_PATH);
2896 				break;
2897 			}
2898 			if (nentries != -1) {
2899 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2900 				break;
2901 			}
2902 			if (itree->nentries < -1) {
2903 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2904 				break;
2905 			}
2906 			if (itree->nentries == -1) {
2907 				/* Tree was not found in pack file. */
2908 				err = cb_tree(cb_arg, NULL, mtime, &tree_id,
2909 				    path, repo);
2910 				break;
2911 			}
2912 			if (itree->nentries > INT_MAX) {
2913 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2914 				break;
2915 			}
2916 			tree.entries = calloc(itree->nentries,
2917 			    sizeof(struct got_tree_entry));
2918 			if (tree.entries == NULL) {
2919 				err = got_error_from_errno("calloc");
2920 				break;
2921 			}
2922 			if (itree->nentries == 0) {
2923 				err = cb_tree(cb_arg, &tree, mtime, &tree_id,
2924 				    path, repo);
2925 				if (err)
2926 					break;
2927 
2928 				/* Prepare for next tree. */
2929 				free(tree.entries);
2930 				memset(&tree, 0, sizeof(tree));
2931 				nentries = -1;
2932 			} else {
2933 				tree.nentries = itree->nentries;
2934 				nentries = 0;
2935 			}
2936 			break;
2937 		case GOT_IMSG_TREE_ENTRIES:
2938 			/* Should be preceeded by GOT_IMSG_ENUMERATED_TREE. */
2939 			if (nentries <= -1) {
2940 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2941 				break;
2942 			}
2943 			err = recv_tree_entries(imsg.data, datalen,
2944 			    &tree, &nentries);
2945 			if (err)
2946 				break;
2947 			if (tree.nentries == nentries) {
2948 				err = cb_tree(cb_arg, &tree, mtime, &tree_id,
2949 				    path, repo);
2950 				if (err)
2951 					break;
2952 
2953 				/* Prepare for next tree. */
2954 				free(tree.entries);
2955 				memset(&tree, 0, sizeof(tree));
2956 				nentries = -1;
2957 			}
2958 			break;
2959 		case GOT_IMSG_TREE_ENUMERATION_DONE:
2960 			/* All trees have been found and traversed. */
2961 			if (!have_commit || path == NULL || nentries != -1) {
2962 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2963 				break;
2964 			}
2965 			err = cb_commit(cb_arg, mtime, &commit_id, repo);
2966 			if (err)
2967 				break;
2968 			have_commit = 0;
2969 			break;
2970 		case GOT_IMSG_OBJECT_ENUMERATION_DONE:
2971 			*found_all_objects = 1;
2972 			done = 1;
2973 			break;
2974 		case GOT_IMSG_OBJECT_ENUMERATION_INCOMPLETE:
2975 			done = 1;
2976 			break;
2977 		default:
2978 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2979 			break;
2980 		}
2981 
2982 		imsg_free(&imsg);
2983 		if (err)
2984 			break;
2985 	}
2986 
2987 	free(path);
2988 	free(canon_path);
2989 	free(tree.entries);
2990 	return err;
2991 }
2992 
2993 const struct got_error *
2994 got_privsep_send_raw_delta_req(struct imsgbuf *ibuf, int idx,
2995     struct got_object_id *id)
2996 {
2997 	struct got_imsg_raw_delta_request dreq;
2998 
2999 	memset(&dreq, 0, sizeof(dreq));
3000 	dreq.idx = idx;
3001 	memcpy(dreq.id, id->sha1, SHA1_DIGEST_LENGTH);
3002 
3003 	if (imsg_compose(ibuf, GOT_IMSG_RAW_DELTA_REQUEST, 0, 0, -1,
3004 	    &dreq, sizeof(dreq)) == -1)
3005 		return got_error_from_errno("imsg_compose RAW_DELTA_REQUEST");
3006 
3007 	return flush_imsg(ibuf);
3008 }
3009 
3010 const struct got_error *
3011 got_privsep_send_raw_delta_outfd(struct imsgbuf *ibuf, int fd)
3012 {
3013 	return send_fd(ibuf, GOT_IMSG_RAW_DELTA_OUTFD, fd);
3014 }
3015 
3016 const struct got_error *
3017 got_privsep_send_raw_delta(struct imsgbuf *ibuf, uint64_t base_size,
3018     uint64_t result_size,  off_t delta_size, off_t delta_compressed_size,
3019     off_t delta_offset, off_t delta_out_offset, struct got_object_id *base_id)
3020 {
3021 	struct got_imsg_raw_delta idelta;
3022 	int ret;
3023 
3024 	memset(&idelta, 0, sizeof(idelta));
3025 	idelta.base_size = base_size;
3026 	idelta.result_size = result_size;
3027 	idelta.delta_size = delta_size;
3028 	idelta.delta_compressed_size = delta_compressed_size;
3029 	idelta.delta_offset = delta_offset;
3030 	idelta.delta_out_offset = delta_out_offset;
3031 	memcpy(idelta.base_id, base_id->sha1, SHA1_DIGEST_LENGTH);
3032 
3033 	ret = imsg_compose(ibuf, GOT_IMSG_RAW_DELTA, 0, 0, -1,
3034 	    &idelta, sizeof(idelta));
3035 	if (ret == -1)
3036 		return got_error_from_errno("imsg_compose RAW_DELTA");
3037 
3038 	return flush_imsg(ibuf);
3039 }
3040 
3041 const struct got_error *
3042 got_privsep_recv_raw_delta(uint64_t *base_size, uint64_t *result_size,
3043     off_t *delta_size, off_t *delta_compressed_size, off_t *delta_offset,
3044     off_t *delta_out_offset, struct got_object_id **base_id, struct imsgbuf *ibuf)
3045 {
3046 	const struct got_error *err = NULL;
3047 	struct imsg imsg;
3048 	struct got_imsg_raw_delta *delta;
3049 	size_t datalen;
3050 
3051 	*base_size = 0;
3052 	*result_size = 0;
3053 	*delta_size = 0;
3054 	*delta_compressed_size = 0;
3055 	*delta_offset = 0;
3056 	*delta_out_offset = 0;
3057 	*base_id = NULL;
3058 
3059 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3060 	if (err)
3061 		return err;
3062 
3063 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3064 
3065 	switch (imsg.hdr.type) {
3066 	case GOT_IMSG_RAW_DELTA:
3067 		if (datalen != sizeof(*delta)) {
3068 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3069 			break;
3070 		}
3071 		delta = imsg.data;
3072 		*base_size = delta->base_size;
3073 		*result_size = delta->result_size;
3074 		*delta_size = delta->delta_size;
3075 		*delta_compressed_size = delta->delta_compressed_size;
3076 		*delta_offset = delta->delta_offset;
3077 		*delta_out_offset = delta->delta_out_offset;
3078 		*base_id = calloc(1, sizeof(**base_id));
3079 		if (*base_id == NULL) {
3080 			err = got_error_from_errno("malloc");
3081 			break;
3082 		}
3083 		memcpy((*base_id)->sha1, delta->base_id, SHA1_DIGEST_LENGTH);
3084 		break;
3085 	default:
3086 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3087 		break;
3088 	}
3089 
3090 	imsg_free(&imsg);
3091 
3092 	if (err) {
3093 		free(*base_id);
3094 		*base_id = NULL;
3095 	}
3096 	return err;
3097 }
3098 
3099 static const struct got_error *
3100 send_idlist(struct imsgbuf *ibuf, struct got_object_id **ids, size_t nids)
3101 {
3102 	const struct got_error *err = NULL;
3103 	struct got_imsg_object_idlist idlist;
3104 	struct ibuf *wbuf;
3105 	size_t i;
3106 
3107 	memset(&idlist, 0, sizeof(idlist));
3108 
3109 	if (nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS)
3110 		return got_error(GOT_ERR_NO_SPACE);
3111 
3112 	wbuf = imsg_create(ibuf, GOT_IMSG_OBJ_ID_LIST, 0, 0,
3113 	    sizeof(idlist) + nids * sizeof(**ids));
3114 	if (wbuf == NULL) {
3115 		err = got_error_from_errno("imsg_create OBJ_ID_LIST");
3116 		return err;
3117 	}
3118 
3119 	idlist.nids = nids;
3120 	if (imsg_add(wbuf, &idlist, sizeof(idlist)) == -1)
3121 		return got_error_from_errno("imsg_add OBJ_ID_LIST");
3122 
3123 	for (i = 0; i < nids; i++) {
3124 		struct got_object_id *id = ids[i];
3125 		if (imsg_add(wbuf, id, sizeof(*id)) == -1)
3126 			return got_error_from_errno("imsg_add OBJ_ID_LIST");
3127 	}
3128 
3129 	wbuf->fd = -1;
3130 	imsg_close(ibuf, wbuf);
3131 
3132 	return flush_imsg(ibuf);
3133 }
3134 
3135 const struct got_error *
3136 got_privsep_send_object_idlist(struct imsgbuf *ibuf,
3137     struct got_object_id **ids, size_t nids)
3138 {
3139 	const struct got_error *err = NULL;
3140 	struct got_object_id *idlist[GOT_IMSG_OBJ_ID_LIST_MAX_NIDS];
3141 	int i, queued = 0;
3142 
3143 	for (i = 0; i < nids; i++) {
3144 		idlist[i % nitems(idlist)] = ids[i];
3145 		queued++;
3146 		if (queued >= nitems(idlist)) {
3147 			err = send_idlist(ibuf, idlist, queued);
3148 			if (err)
3149 				return err;
3150 			queued = 0;
3151 		}
3152 	}
3153 
3154 	if (queued > 0) {
3155 		err = send_idlist(ibuf, idlist, queued);
3156 		if (err)
3157 			return err;
3158 	}
3159 
3160 	return NULL;
3161 }
3162 
3163 const struct got_error *
3164 got_privsep_send_object_idlist_done(struct imsgbuf *ibuf)
3165 {
3166 	if (imsg_compose(ibuf, GOT_IMSG_OBJ_ID_LIST_DONE, 0, 0, -1, NULL, 0)
3167 	    == -1)
3168 		return got_error_from_errno("imsg_compose OBJ_ID_LIST_DONE");
3169 
3170 	return flush_imsg(ibuf);
3171 }
3172 
3173 const struct got_error *
3174 got_privsep_recv_object_idlist(int *done, struct got_object_id **ids,
3175     size_t *nids, struct imsgbuf *ibuf)
3176 {
3177 	const struct got_error *err = NULL;
3178 	struct imsg imsg;
3179 	struct got_imsg_object_idlist *idlist;
3180 	size_t datalen;
3181 
3182 	*ids = NULL;
3183 	*done = 0;
3184 	*nids = 0;
3185 
3186 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3187 	if (err)
3188 		return err;
3189 
3190 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3191 	switch (imsg.hdr.type) {
3192 	case GOT_IMSG_OBJ_ID_LIST:
3193 		if (datalen < sizeof(*idlist)) {
3194 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3195 			break;
3196 		}
3197 		idlist = imsg.data;
3198 		if (idlist->nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS ||
3199 		    idlist->nids * sizeof(**ids) > datalen - sizeof(*idlist)) {
3200 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3201 			break;
3202 		}
3203 		*nids = idlist->nids;
3204 		*ids = calloc(*nids, sizeof(**ids));
3205 		if (*ids == NULL) {
3206 			err = got_error_from_errno("calloc");
3207 			break;
3208 		}
3209 		memcpy(*ids, (uint8_t *)imsg.data + sizeof(*idlist),
3210 		    *nids * sizeof(**ids));
3211 		break;
3212 	case GOT_IMSG_OBJ_ID_LIST_DONE:
3213 		*done = 1;
3214 		break;
3215 	default:
3216 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3217 		break;
3218 	}
3219 
3220 	imsg_free(&imsg);
3221 
3222 	return err;
3223 }
3224 
3225 const struct got_error *
3226 got_privsep_send_delta_reuse_req(struct imsgbuf *ibuf)
3227 {
3228 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_REQUEST, 0, 0, -1, NULL, 0)
3229 	    == -1)
3230 		return got_error_from_errno("imsg_compose DELTA_REUSE_REQUEST");
3231 
3232 	return flush_imsg(ibuf);
3233 }
3234 
3235 const struct got_error *
3236 got_privsep_send_reused_deltas(struct imsgbuf *ibuf,
3237     struct got_imsg_reused_delta *deltas, size_t ndeltas)
3238 {
3239 	const struct got_error *err = NULL;
3240 	struct ibuf *wbuf;
3241 	struct got_imsg_reused_deltas ideltas;
3242 	size_t i;
3243 
3244 	memset(&ideltas, 0, sizeof(ideltas));
3245 
3246 	if (ndeltas > GOT_IMSG_REUSED_DELTAS_MAX_NDELTAS)
3247 		return got_error(GOT_ERR_NO_SPACE);
3248 
3249 	wbuf = imsg_create(ibuf, GOT_IMSG_REUSED_DELTAS, 0, 0,
3250 	    sizeof(ideltas) + ndeltas * sizeof(*deltas));
3251 	if (wbuf == NULL) {
3252 		err = got_error_from_errno("imsg_create REUSED_DELTAS");
3253 		return err;
3254 	}
3255 
3256 	ideltas.ndeltas = ndeltas;
3257 	if (imsg_add(wbuf, &ideltas, sizeof(ideltas)) == -1)
3258 		return got_error_from_errno("imsg_add REUSED_DELTAS");
3259 
3260 	for (i = 0; i < ndeltas; i++) {
3261 		struct got_imsg_reused_delta *delta = &deltas[i];
3262 		if (imsg_add(wbuf, delta, sizeof(*delta)) == -1)
3263 			return got_error_from_errno("imsg_add REUSED_DELTAS");
3264 	}
3265 
3266 	wbuf->fd = -1;
3267 	imsg_close(ibuf, wbuf);
3268 
3269 	return flush_imsg(ibuf);
3270 }
3271 
3272 const struct got_error *
3273 got_privsep_send_reused_deltas_done(struct imsgbuf *ibuf)
3274 {
3275 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_DONE, 0, 0, -1, NULL, 0)
3276 	    == -1)
3277 		return got_error_from_errno("imsg_compose DELTA_REUSE_DONE");
3278 
3279 	return flush_imsg(ibuf);
3280 }
3281 
3282 const struct got_error *
3283 got_privsep_recv_reused_deltas(int *done, struct got_imsg_reused_delta *deltas,
3284     size_t *ndeltas, struct imsgbuf *ibuf)
3285 {
3286 	const struct got_error *err = NULL;
3287 	struct imsg imsg;
3288 	struct got_imsg_reused_deltas *ideltas;
3289 	size_t datalen;
3290 
3291 	*done = 0;
3292 	*ndeltas = 0;
3293 
3294 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3295 	if (err)
3296 		return err;
3297 
3298 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3299 	switch (imsg.hdr.type) {
3300 	case GOT_IMSG_REUSED_DELTAS:
3301 		if (datalen < sizeof(*ideltas)) {
3302 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3303 			break;
3304 		}
3305 		ideltas = imsg.data;
3306 		if (ideltas->ndeltas > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS ||
3307 		    ideltas->ndeltas * sizeof(*deltas) >
3308 		    datalen - sizeof(*ideltas)) {
3309 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3310 			break;
3311 		}
3312 		*ndeltas = ideltas->ndeltas;
3313 		memcpy(deltas, (uint8_t *)imsg.data + sizeof(*ideltas),
3314 		    *ndeltas * sizeof(*deltas));
3315 		break;
3316 	case GOT_IMSG_DELTA_REUSE_DONE:
3317 		*done = 1;
3318 		break;
3319 	default:
3320 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3321 		break;
3322 	}
3323 
3324 	imsg_free(&imsg);
3325 
3326 	return err;
3327 }
3328 
3329 const struct got_error *
3330 got_privsep_init_commit_painting(struct imsgbuf *ibuf)
3331 {
3332 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_PAINTING_INIT,
3333 	    0, 0, -1, NULL, 0)
3334 	    == -1)
3335 		return got_error_from_errno("imsg_compose "
3336 		    "COMMIT_PAINTING_INIT");
3337 
3338 	return flush_imsg(ibuf);
3339 }
3340 
3341 const struct got_error *
3342 got_privsep_send_painting_request(struct imsgbuf *ibuf, int idx,
3343     struct got_object_id *id, intptr_t color)
3344 {
3345 	struct got_imsg_commit_painting_request ireq;
3346 
3347 	memset(&ireq, 0, sizeof(ireq));
3348 	memcpy(ireq.id, id->sha1, sizeof(ireq.id));
3349 	ireq.idx = idx;
3350 	ireq.color = color;
3351 
3352 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_PAINTING_REQUEST, 0, 0, -1,
3353 	    &ireq, sizeof(ireq)) == -1)
3354 		return got_error_from_errno("imsg_compose "
3355 		    "COMMIT_PAINTING_REQUEST");
3356 
3357 	return flush_imsg(ibuf);
3358 }
3359 
3360 static const struct got_error *
3361 send_painted_commits(struct got_object_id_queue *ids, int *nids,
3362     size_t remain, int present_in_pack, struct imsgbuf *ibuf)
3363 {
3364 	const struct got_error *err = NULL;
3365 	struct ibuf *wbuf = NULL;
3366 	struct got_object_qid *qid;
3367 	size_t msglen;
3368 	int ncommits;
3369 	intptr_t color;
3370 
3371 	msglen = MIN(remain, MAX_IMSGSIZE - IMSG_HEADER_SIZE);
3372 	ncommits = (msglen - sizeof(struct got_imsg_painted_commits)) /
3373 	    sizeof(struct got_imsg_painted_commit);
3374 
3375 	wbuf = imsg_create(ibuf, GOT_IMSG_PAINTED_COMMITS, 0, 0, msglen);
3376 	if (wbuf == NULL) {
3377 		err = got_error_from_errno("imsg_create PAINTED_COMMITS");
3378 		return err;
3379 	}
3380 
3381 	/* Keep in sync with struct got_imsg_painted_commits! */
3382 	if (imsg_add(wbuf, &ncommits, sizeof(ncommits)) == -1)
3383 		return got_error_from_errno("imsg_add PAINTED_COMMITS");
3384 	if (imsg_add(wbuf, &present_in_pack, sizeof(present_in_pack)) == -1)
3385 		return got_error_from_errno("imsg_add PAINTED_COMMITS");
3386 
3387 	while (ncommits > 0) {
3388 		qid = STAILQ_FIRST(ids);
3389 		STAILQ_REMOVE_HEAD(ids, entry);
3390 		ncommits--;
3391 		(*nids)--;
3392 		color = (intptr_t)qid->data;
3393 
3394 		/* Keep in sync with struct got_imsg_painted_commit! */
3395 		if (imsg_add(wbuf, qid->id.sha1, SHA1_DIGEST_LENGTH) == -1)
3396 			return got_error_from_errno("imsg_add PAINTED_COMMITS");
3397 		if (imsg_add(wbuf, &color, sizeof(color)) == -1)
3398 			return got_error_from_errno("imsg_add PAINTED_COMMITS");
3399 
3400 		got_object_qid_free(qid);
3401 	}
3402 
3403 	wbuf->fd = -1;
3404 	imsg_close(ibuf, wbuf);
3405 
3406 	return flush_imsg(ibuf);
3407 }
3408 
3409 const struct got_error *
3410 got_privsep_send_painted_commits(struct imsgbuf *ibuf,
3411     struct got_object_id_queue *ids, int *nids,
3412     int present_in_pack, int flush)
3413 {
3414 	const struct got_error *err;
3415 	size_t remain;
3416 
3417 	if (*nids <= 0)
3418 		return NULL;
3419 
3420 	do {
3421 		remain = (sizeof(struct got_imsg_painted_commits)) +
3422 		    *nids * sizeof(struct got_imsg_painted_commit);
3423 		if (flush || remain >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
3424 			err = send_painted_commits(ids, nids, remain,
3425 			    present_in_pack, ibuf);
3426 			if (err)
3427 				return err;
3428 		}
3429 	} while (flush && *nids > 0);
3430 
3431 	return NULL;
3432 }
3433 
3434 const struct got_error *
3435 got_privsep_send_painting_commits_done(struct imsgbuf *ibuf)
3436 {
3437 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_PAINTING_DONE,
3438 	    0, 0, -1, NULL, 0)
3439 	    == -1)
3440 		return got_error_from_errno("imsg_compose "
3441 		    "COMMIT_PAINTING_DONE");
3442 
3443 	return flush_imsg(ibuf);
3444 }
3445 
3446 const struct got_error *
3447 got_privsep_recv_painted_commits(struct got_object_id_queue *new_ids,
3448     got_privsep_recv_painted_commit_cb cb, void *cb_arg, struct imsgbuf *ibuf)
3449 {
3450 	const struct got_error *err = NULL;
3451 	struct imsg imsg;
3452 	struct got_imsg_painted_commits icommits;
3453 	struct got_imsg_painted_commit icommit;
3454 	size_t datalen;
3455 	int i;
3456 
3457 	for (;;) {
3458 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3459 		if (err)
3460 			return err;
3461 
3462 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3463 		if (imsg.hdr.type == GOT_IMSG_COMMIT_PAINTING_DONE)
3464 			break;
3465 		if (imsg.hdr.type != GOT_IMSG_PAINTED_COMMITS)
3466 			return got_error(GOT_ERR_PRIVSEP_MSG);
3467 
3468 		if (datalen < sizeof(icommits))
3469 			return got_error(GOT_ERR_PRIVSEP_LEN);
3470 		memcpy(&icommits, imsg.data, sizeof(icommits));
3471 		if (icommits.ncommits * sizeof(icommit) < icommits.ncommits ||
3472 		    datalen < sizeof(icommits) +
3473 		    icommits.ncommits * sizeof(icommit))
3474 			return got_error(GOT_ERR_PRIVSEP_LEN);
3475 
3476 		for (i = 0; i < icommits.ncommits; i++) {
3477 			memcpy(&icommit,
3478 			    (uint8_t *)imsg.data + sizeof(icommits) + i * sizeof(icommit),
3479 			    sizeof(icommit));
3480 
3481 			if (icommits.present_in_pack) {
3482 				struct got_object_id id;
3483 				memcpy(id.sha1, icommit.id, SHA1_DIGEST_LENGTH);
3484 				err = cb(cb_arg, &id, icommit.color);
3485 				if (err)
3486 					break;
3487 			} else {
3488 				struct got_object_qid *qid;
3489 				err = got_object_qid_alloc_partial(&qid);
3490 				if (err)
3491 					break;
3492 				memcpy(qid->id.sha1, icommit.id,
3493 				    SHA1_DIGEST_LENGTH);
3494 				qid->data = (void *)icommit.color;
3495 				STAILQ_INSERT_TAIL(new_ids, qid, entry);
3496 			}
3497 		}
3498 
3499 		imsg_free(&imsg);
3500 	}
3501 
3502 	return err;
3503 }
3504 
3505 const struct got_error *
3506 got_privsep_unveil_exec_helpers(void)
3507 {
3508 	const char *helpers[] = {
3509 	    GOT_PATH_PROG_READ_PACK,
3510 	    GOT_PATH_PROG_READ_OBJECT,
3511 	    GOT_PATH_PROG_READ_COMMIT,
3512 	    GOT_PATH_PROG_READ_TREE,
3513 	    GOT_PATH_PROG_READ_BLOB,
3514 	    GOT_PATH_PROG_READ_TAG,
3515 	    GOT_PATH_PROG_READ_GITCONFIG,
3516 	    GOT_PATH_PROG_READ_GOTCONFIG,
3517 	    GOT_PATH_PROG_READ_PATCH,
3518 	    GOT_PATH_PROG_FETCH_PACK,
3519 	    GOT_PATH_PROG_INDEX_PACK,
3520 	    GOT_PATH_PROG_SEND_PACK,
3521 	};
3522 	size_t i;
3523 
3524 	for (i = 0; i < nitems(helpers); i++) {
3525 		if (unveil(helpers[i], "x") == 0)
3526 			continue;
3527 		return got_error_from_errno2("unveil", helpers[i]);
3528 	}
3529 
3530 	return NULL;
3531 }
3532 
3533 void
3534 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
3535 {
3536 	if (close(imsg_fds[0]) == -1) {
3537 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3538 		_exit(1);
3539 	}
3540 
3541 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
3542 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3543 		_exit(1);
3544 	}
3545 
3546 	closefrom(GOT_IMSG_FD_CHILD + 1);
3547 
3548 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
3549 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
3550 		    strerror(errno));
3551 		_exit(1);
3552 	}
3553 }