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 = SHA1_DIGEST_LENGTH + sizeof(pte->mode) +
1474 		    sizeof(pte->namelen) + pte->namelen;
1475 
1476 		if (j > 0 &&
1477 		    entries_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1478 			err = send_tree_entries_batch(ibuf, entries,
1479 			    i, j - 1, entries_len);
1480 			if (err)
1481 				return err;
1482 			i = j;
1483 			entries_len = sizeof(struct got_imsg_tree_entries);
1484 		}
1485 
1486 		entries_len += len;
1487 	}
1488 
1489 	if (j > 0) {
1490 		err = send_tree_entries_batch(ibuf, entries, i, j - 1,
1491 		    entries_len);
1492 		if (err)
1493 			return err;
1494 	}
1495 
1496 	return NULL;
1497 }
1498 
1499 const struct got_error *
1500 got_privsep_send_tree(struct imsgbuf *ibuf,
1501     struct got_parsed_tree_entry *entries, int nentries)
1502 {
1503 	const struct got_error *err = NULL;
1504 	struct got_imsg_tree_object itree;
1505 
1506 	memset(&itree, 0, sizeof(itree));
1507 	itree.nentries = nentries;
1508 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1509 	    == -1)
1510 		return got_error_from_errno("imsg_compose TREE");
1511 
1512 	err = send_tree_entries(ibuf, entries, nentries);
1513 	if (err)
1514 		return err;
1515 
1516 	return flush_imsg(ibuf);
1517 }
1518 
1519 
1520 static const struct got_error *
1521 recv_tree_entries(void *data, size_t datalen, struct got_tree_object *tree,
1522     int *nentries)
1523 {
1524 	const struct got_error *err = NULL;
1525 	struct got_imsg_tree_entries *ientries;
1526 	struct got_tree_entry *te;
1527 	size_t te_offset;
1528 	size_t i;
1529 
1530 	if (datalen <= sizeof(*ientries) ||
1531 	    datalen > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
1532 		return got_error(GOT_ERR_PRIVSEP_LEN);
1533 
1534 	ientries = (struct got_imsg_tree_entries *)data;
1535 	if (ientries->nentries > INT_MAX) {
1536 		return got_error_msg(GOT_ERR_NO_SPACE,
1537 		    "too many tree entries");
1538 	}
1539 
1540 	te_offset = sizeof(*ientries);
1541 	for (i = 0; i < ientries->nentries; i++) {
1542 		struct got_imsg_tree_entry ite;
1543 		const char *te_name;
1544 		uint8_t *buf = (uint8_t *)data + te_offset;
1545 
1546 		if (te_offset >= datalen) {
1547 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1548 			break;
1549 		}
1550 
1551 		/* Might not be aligned, size is ~32 bytes. */
1552 		memcpy(&ite, buf, sizeof(ite));
1553 
1554 		if (ite.namelen >= sizeof(te->name)) {
1555 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1556 			break;
1557 		}
1558 		if (te_offset + sizeof(ite) + ite.namelen > datalen) {
1559 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1560 			break;
1561 		}
1562 
1563 		if (*nentries >= tree->nentries) {
1564 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1565 			break;
1566 		}
1567 		te = &tree->entries[*nentries];
1568 		te_name = buf + sizeof(ite);
1569 		memcpy(te->name, te_name, ite.namelen);
1570 		te->name[ite.namelen] = '\0';
1571 		memcpy(te->id.sha1, ite.id, SHA1_DIGEST_LENGTH);
1572 		te->mode = ite.mode;
1573 		te->idx = *nentries;
1574 		(*nentries)++;
1575 
1576 		te_offset += sizeof(ite) + ite.namelen;
1577 	}
1578 
1579 	return err;
1580 }
1581 
1582 const struct got_error *
1583 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1584 {
1585 	const struct got_error *err = NULL;
1586 	const size_t min_datalen =
1587 	    MIN(sizeof(struct got_imsg_error),
1588 	    sizeof(struct got_imsg_tree_object));
1589 	struct got_imsg_tree_object *itree;
1590 	int nentries = 0;
1591 
1592 	*tree = NULL;
1593 
1594 	err = read_imsg(ibuf);
1595 	if (err)
1596 		goto done;
1597 
1598 	for (;;) {
1599 		struct imsg imsg;
1600 		size_t n;
1601 		size_t datalen;
1602 
1603 		n = imsg_get(ibuf, &imsg);
1604 		if (n == 0) {
1605 			if ((*tree)) {
1606 				if (nentries < (*tree)->nentries) {
1607 					err = read_imsg(ibuf);
1608 					if (err)
1609 						break;
1610 					continue;
1611 				} else
1612 					break;
1613 			} else {
1614 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1615 				break;
1616 			}
1617 		}
1618 
1619 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen) {
1620 			imsg_free(&imsg);
1621 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1622 			break;
1623 		}
1624 
1625 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1626 
1627 		switch (imsg.hdr.type) {
1628 		case GOT_IMSG_ERROR:
1629 			err = recv_imsg_error(&imsg, datalen);
1630 			break;
1631 		case GOT_IMSG_TREE:
1632 			/* This message should only appear once. */
1633 			if (*tree != NULL) {
1634 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1635 				break;
1636 			}
1637 			if (datalen != sizeof(*itree)) {
1638 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1639 				break;
1640 			}
1641 			itree = imsg.data;
1642 			if (itree->nentries < 0) {
1643 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1644 				break;
1645 			}
1646 			*tree = malloc(sizeof(**tree));
1647 			if (*tree == NULL) {
1648 				err = got_error_from_errno("malloc");
1649 				break;
1650 			}
1651 			(*tree)->entries = calloc(itree->nentries,
1652 			    sizeof(struct got_tree_entry));
1653 			if ((*tree)->entries == NULL) {
1654 				err = got_error_from_errno("malloc");
1655 				free(*tree);
1656 				*tree = NULL;
1657 				break;
1658 			}
1659 			(*tree)->nentries = itree->nentries;
1660 			(*tree)->refcnt = 0;
1661 			break;
1662 		case GOT_IMSG_TREE_ENTRIES:
1663 			/* This message should be preceeded by GOT_IMSG_TREE. */
1664 			if (*tree == NULL) {
1665 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1666 				break;
1667 			}
1668 			err = recv_tree_entries(imsg.data, datalen,
1669 			    *tree, &nentries);
1670 			break;
1671 		default:
1672 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1673 			break;
1674 		}
1675 
1676 		imsg_free(&imsg);
1677 		if (err)
1678 			break;
1679 	}
1680 done:
1681 	if (*tree && (*tree)->nentries != nentries) {
1682 		if (err == NULL)
1683 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1684 		got_object_tree_close(*tree);
1685 		*tree = NULL;
1686 	}
1687 
1688 	return err;
1689 }
1690 
1691 const struct got_error *
1692 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1693     const uint8_t *data)
1694 {
1695 	struct got_imsg_blob iblob;
1696 
1697 	memset(&iblob, 0, sizeof(iblob));
1698 	iblob.size = size;
1699 	iblob.hdrlen = hdrlen;
1700 
1701 	if (data) {
1702 		uint8_t *buf;
1703 
1704 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1705 			return got_error(GOT_ERR_NO_SPACE);
1706 
1707 		buf = malloc(sizeof(iblob) + size);
1708 		if (buf == NULL)
1709 			return got_error_from_errno("malloc");
1710 
1711 		memcpy(buf, &iblob, sizeof(iblob));
1712 		memcpy(buf + sizeof(iblob), data, size);
1713 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1714 		    sizeof(iblob) + size) == -1) {
1715 			free(buf);
1716 			return got_error_from_errno("imsg_compose BLOB");
1717 		}
1718 		free(buf);
1719 	} else {
1720 		/* Data has already been written to file descriptor. */
1721 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1722 		    sizeof(iblob)) == -1)
1723 			return got_error_from_errno("imsg_compose BLOB");
1724 	}
1725 
1726 
1727 	return flush_imsg(ibuf);
1728 }
1729 
1730 const struct got_error *
1731 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1732     struct imsgbuf *ibuf)
1733 {
1734 	const struct got_error *err = NULL;
1735 	struct imsg imsg;
1736 	struct got_imsg_blob *iblob;
1737 	size_t datalen;
1738 
1739 	*outbuf = NULL;
1740 
1741 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1742 	if (err)
1743 		return err;
1744 
1745 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1746 
1747 	switch (imsg.hdr.type) {
1748 	case GOT_IMSG_BLOB:
1749 		if (datalen < sizeof(*iblob)) {
1750 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1751 			break;
1752 		}
1753 		iblob = imsg.data;
1754 		*size = iblob->size;
1755 		*hdrlen = iblob->hdrlen;
1756 
1757 		if (datalen == sizeof(*iblob)) {
1758 			/* Data has been written to file descriptor. */
1759 			break;
1760 		}
1761 
1762 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX ||
1763 		    *size > datalen + sizeof(*iblob)) {
1764 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1765 			break;
1766 		}
1767 
1768 		*outbuf = malloc(*size);
1769 		if (*outbuf == NULL) {
1770 			err = got_error_from_errno("malloc");
1771 			break;
1772 		}
1773 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1774 		break;
1775 	default:
1776 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1777 		break;
1778 	}
1779 
1780 	imsg_free(&imsg);
1781 
1782 	return err;
1783 }
1784 
1785 static const struct got_error *
1786 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1787 {
1788 	const struct got_error *err = NULL;
1789 	size_t offset, remain;
1790 
1791 	offset = 0;
1792 	remain = tagmsg_len;
1793 	while (remain > 0) {
1794 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1795 
1796 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1797 		    tag->tagmsg + offset, n) == -1) {
1798 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1799 			break;
1800 		}
1801 
1802 		err = flush_imsg(ibuf);
1803 		if (err)
1804 			break;
1805 
1806 		offset += n;
1807 		remain -= n;
1808 	}
1809 
1810 	return err;
1811 }
1812 
1813 const struct got_error *
1814 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1815 {
1816 	const struct got_error *err = NULL;
1817 	struct got_imsg_tag_object *itag;
1818 	uint8_t *buf;
1819 	size_t len, total;
1820 	size_t tag_len = strlen(tag->tag);
1821 	size_t tagger_len = strlen(tag->tagger);
1822 	size_t tagmsg_len = strlen(tag->tagmsg);
1823 
1824 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1825 
1826 	buf = malloc(total);
1827 	if (buf == NULL)
1828 		return got_error_from_errno("malloc");
1829 
1830 	itag = (struct got_imsg_tag_object *)buf;
1831 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1832 	itag->obj_type = tag->obj_type;
1833 	itag->tag_len = tag_len;
1834 	itag->tagger_len = tagger_len;
1835 	itag->tagger_time = tag->tagger_time;
1836 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1837 	itag->tagmsg_len = tagmsg_len;
1838 
1839 	len = sizeof(*itag);
1840 	memcpy(buf + len, tag->tag, tag_len);
1841 	len += tag_len;
1842 	memcpy(buf + len, tag->tagger, tagger_len);
1843 	len += tagger_len;
1844 
1845 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1846 		err = got_error_from_errno("imsg_compose TAG");
1847 		goto done;
1848 	}
1849 
1850 	if (tagmsg_len == 0 ||
1851 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1852 		err = flush_imsg(ibuf);
1853 		if (err)
1854 			goto done;
1855 	}
1856 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1857 done:
1858 	free(buf);
1859 	return err;
1860 }
1861 
1862 const struct got_error *
1863 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1864 {
1865 	const struct got_error *err = NULL;
1866 	struct imsg imsg;
1867 	struct got_imsg_tag_object *itag;
1868 	size_t len, datalen;
1869 	const size_t min_datalen =
1870 	    MIN(sizeof(struct got_imsg_error),
1871 	    sizeof(struct got_imsg_tag_object));
1872 
1873 	*tag = NULL;
1874 
1875 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1876 	if (err)
1877 		return err;
1878 
1879 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1880 	len = 0;
1881 
1882 	switch (imsg.hdr.type) {
1883 	case GOT_IMSG_TAG:
1884 		if (datalen < sizeof(*itag)) {
1885 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1886 			break;
1887 		}
1888 		itag = imsg.data;
1889 		if (datalen != sizeof(*itag) + itag->tag_len +
1890 		    itag->tagger_len) {
1891 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1892 			break;
1893 		}
1894 		len += sizeof(*itag);
1895 
1896 		*tag = calloc(1, sizeof(**tag));
1897 		if (*tag == NULL) {
1898 			err = got_error_from_errno("calloc");
1899 			break;
1900 		}
1901 
1902 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1903 
1904 		(*tag)->tag = strndup(imsg.data + len, itag->tag_len);
1905 		if ((*tag)->tag == NULL) {
1906 			err = got_error_from_errno("strndup");
1907 			break;
1908 		}
1909 		len += itag->tag_len;
1910 
1911 		(*tag)->obj_type = itag->obj_type;
1912 		(*tag)->tagger_time = itag->tagger_time;
1913 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1914 
1915 		(*tag)->tagger = strndup(imsg.data + len, itag->tagger_len);
1916 		if ((*tag)->tagger == NULL) {
1917 			err = got_error_from_errno("strndup");
1918 			break;
1919 		}
1920 		len += itag->tagger_len;
1921 
1922 		if (itag->tagmsg_len == 0) {
1923 			(*tag)->tagmsg = strdup("");
1924 			if ((*tag)->tagmsg == NULL) {
1925 				err = got_error_from_errno("strdup");
1926 				break;
1927 			}
1928 		} else {
1929 			size_t offset = 0, remain = itag->tagmsg_len;
1930 
1931 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1932 			if ((*tag)->tagmsg == NULL) {
1933 				err = got_error_from_errno("malloc");
1934 				break;
1935 			}
1936 			while (remain > 0) {
1937 				struct imsg imsg_log;
1938 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1939 				    remain);
1940 
1941 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1942 				if (err)
1943 					return err;
1944 
1945 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1946 					return got_error(GOT_ERR_PRIVSEP_MSG);
1947 
1948 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1949 				    n);
1950 				imsg_free(&imsg_log);
1951 				offset += n;
1952 				remain -= n;
1953 			}
1954 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1955 		}
1956 
1957 		break;
1958 	default:
1959 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1960 		break;
1961 	}
1962 
1963 	imsg_free(&imsg);
1964 
1965 	return err;
1966 }
1967 
1968 const struct got_error *
1969 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1970     struct got_packidx *packidx)
1971 {
1972 	const struct got_error *err = NULL;
1973 	struct got_imsg_packidx ipackidx;
1974 	struct got_imsg_pack ipack;
1975 	int fd;
1976 
1977 	memset(&ipackidx, 0, sizeof(ipackidx));
1978 	memset(&ipack, 0, sizeof(ipack));
1979 
1980 	ipackidx.len = packidx->len;
1981 	ipackidx.packfile_size = pack->filesize;
1982 	fd = dup(packidx->fd);
1983 	if (fd == -1)
1984 		return got_error_from_errno("dup");
1985 
1986 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
1987 	    sizeof(ipackidx)) == -1) {
1988 		err = got_error_from_errno("imsg_compose PACKIDX");
1989 		close(fd);
1990 		return err;
1991 	}
1992 
1993 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
1994 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
1995 		return got_error(GOT_ERR_NO_SPACE);
1996 	ipack.filesize = pack->filesize;
1997 
1998 	fd = dup(pack->fd);
1999 	if (fd == -1)
2000 		return got_error_from_errno("dup");
2001 
2002 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
2003 	    == -1) {
2004 		err = got_error_from_errno("imsg_compose PACK");
2005 		close(fd);
2006 		return err;
2007 	}
2008 
2009 	return flush_imsg(ibuf);
2010 }
2011 
2012 const struct got_error *
2013 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
2014     struct got_object_id *id)
2015 {
2016 	struct got_imsg_packed_object iobj;
2017 
2018 	memset(&iobj, 0, sizeof(iobj));
2019 	iobj.idx = idx;
2020 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2021 
2022 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
2023 	    &iobj, sizeof(iobj)) == -1)
2024 		return got_error_from_errno("imsg_compose "
2025 		    "PACKED_OBJECT_REQUEST");
2026 
2027 	return flush_imsg(ibuf);
2028 }
2029 
2030 const struct got_error *
2031 got_privsep_send_packed_raw_obj_req(struct imsgbuf *ibuf, int idx,
2032     struct got_object_id *id)
2033 {
2034 	struct got_imsg_packed_object iobj;
2035 
2036 	memset(&iobj, 0, sizeof(iobj));
2037 	iobj.idx = idx;
2038 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2039 
2040 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_RAW_OBJECT_REQUEST, 0, 0, -1,
2041 	    &iobj, sizeof(iobj)) == -1)
2042 		return got_error_from_errno("imsg_compose "
2043 		    "PACKED_OBJECT_REQUEST");
2044 
2045 	return flush_imsg(ibuf);
2046 }
2047 
2048 const struct got_error *
2049 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
2050 {
2051 	const struct got_error *err = NULL;
2052 
2053 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
2054 	    NULL, 0) == -1) {
2055 		err = got_error_from_errno("imsg_compose "
2056 		    "GITCONFIG_PARSE_REQUEST");
2057 		close(fd);
2058 		return err;
2059 	}
2060 
2061 	return flush_imsg(ibuf);
2062 }
2063 
2064 const struct got_error *
2065 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
2066 {
2067 	if (imsg_compose(ibuf,
2068 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
2069 	    NULL, 0) == -1)
2070 		return got_error_from_errno("imsg_compose "
2071 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
2072 
2073 	return flush_imsg(ibuf);
2074 }
2075 
2076 const struct got_error *
2077 got_privsep_send_gitconfig_repository_extensions_req(struct imsgbuf *ibuf)
2078 {
2079 	if (imsg_compose(ibuf,
2080 	    GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST, 0, 0, -1,
2081 	    NULL, 0) == -1)
2082 		return got_error_from_errno("imsg_compose "
2083 		    "GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST");
2084 
2085 	return flush_imsg(ibuf);
2086 }
2087 
2088 
2089 const struct got_error *
2090 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
2091 {
2092 	if (imsg_compose(ibuf,
2093 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
2094 		return got_error_from_errno("imsg_compose "
2095 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
2096 
2097 	return flush_imsg(ibuf);
2098 }
2099 
2100 const struct got_error *
2101 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
2102 {
2103 	if (imsg_compose(ibuf,
2104 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
2105 		return got_error_from_errno("imsg_compose "
2106 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
2107 
2108 	return flush_imsg(ibuf);
2109 }
2110 
2111 const struct got_error *
2112 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
2113 {
2114 	if (imsg_compose(ibuf,
2115 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2116 		return got_error_from_errno("imsg_compose "
2117 		    "GITCONFIG_REMOTE_REQUEST");
2118 
2119 	return flush_imsg(ibuf);
2120 }
2121 
2122 const struct got_error *
2123 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
2124 {
2125 	if (imsg_compose(ibuf,
2126 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
2127 		return got_error_from_errno("imsg_compose "
2128 		    "GITCONFIG_OWNER_REQUEST");
2129 
2130 	return flush_imsg(ibuf);
2131 }
2132 
2133 const struct got_error *
2134 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
2135 {
2136 	const struct got_error *err = NULL;
2137 	struct imsg imsg;
2138 	size_t datalen;
2139 
2140 	*str = NULL;
2141 
2142 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2143 	if (err)
2144 		return err;
2145 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2146 
2147 	switch (imsg.hdr.type) {
2148 	case GOT_IMSG_GITCONFIG_STR_VAL:
2149 		if (datalen == 0)
2150 			break;
2151 		/* datalen does not include terminating \0 */
2152 		*str = malloc(datalen + 1);
2153 		if (*str == NULL) {
2154 			err = got_error_from_errno("malloc");
2155 			break;
2156 		}
2157 		memcpy(*str, imsg.data, datalen);
2158 		(*str)[datalen] = '\0';
2159 		break;
2160 	default:
2161 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2162 		break;
2163 	}
2164 
2165 	imsg_free(&imsg);
2166 	return err;
2167 }
2168 
2169 const struct got_error *
2170 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
2171 {
2172 	const struct got_error *err = NULL;
2173 	struct imsg imsg;
2174 	size_t datalen;
2175 	const size_t min_datalen =
2176 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
2177 
2178 	*val = 0;
2179 
2180 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2181 	if (err)
2182 		return err;
2183 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2184 
2185 	switch (imsg.hdr.type) {
2186 	case GOT_IMSG_GITCONFIG_INT_VAL:
2187 		if (datalen != sizeof(*val)) {
2188 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2189 			break;
2190 		}
2191 		memcpy(val, imsg.data, sizeof(*val));
2192 		break;
2193 	default:
2194 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2195 		break;
2196 	}
2197 
2198 	imsg_free(&imsg);
2199 	return err;
2200 }
2201 
2202 static void
2203 free_remote_data(struct got_remote_repo *remote)
2204 {
2205 	int i;
2206 
2207 	free(remote->name);
2208 	free(remote->fetch_url);
2209 	free(remote->send_url);
2210 	for (i = 0; i < remote->nfetch_branches; i++)
2211 		free(remote->fetch_branches[i]);
2212 	free(remote->fetch_branches);
2213 	for (i = 0; i < remote->nsend_branches; i++)
2214 		free(remote->send_branches[i]);
2215 	free(remote->send_branches);
2216 	for (i = 0; i < remote->nfetch_refs; i++)
2217 		free(remote->fetch_refs[i]);
2218 	free(remote->fetch_refs);
2219 }
2220 
2221 const struct got_error *
2222 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
2223     int *nremotes, struct imsgbuf *ibuf)
2224 {
2225 	const struct got_error *err = NULL;
2226 	struct imsg imsg;
2227 	size_t datalen;
2228 	struct got_imsg_remotes iremotes;
2229 	struct got_imsg_remote iremote;
2230 
2231 	*remotes = NULL;
2232 	*nremotes = 0;
2233 	iremotes.nremotes = 0;
2234 
2235 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
2236 	if (err)
2237 		return err;
2238 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2239 
2240 	switch (imsg.hdr.type) {
2241 	case GOT_IMSG_GITCONFIG_REMOTES:
2242 		if (datalen != sizeof(iremotes)) {
2243 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2244 			break;
2245 		}
2246 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2247 		if (iremotes.nremotes == 0) {
2248 			imsg_free(&imsg);
2249 			return NULL;
2250 		}
2251 		break;
2252 	default:
2253 		imsg_free(&imsg);
2254 		return got_error(GOT_ERR_PRIVSEP_MSG);
2255 	}
2256 
2257 	imsg_free(&imsg);
2258 
2259 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2260 	if (*remotes == NULL)
2261 		return got_error_from_errno("recallocarray");
2262 
2263 	while (*nremotes < iremotes.nremotes) {
2264 		struct got_remote_repo *remote;
2265 
2266 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
2267 		if (err)
2268 			break;
2269 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2270 
2271 		switch (imsg.hdr.type) {
2272 		case GOT_IMSG_GITCONFIG_REMOTE:
2273 			remote = &(*remotes)[*nremotes];
2274 			memset(remote, 0, sizeof(*remote));
2275 			if (datalen < sizeof(iremote)) {
2276 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2277 				break;
2278 			}
2279 			memcpy(&iremote, imsg.data, sizeof(iremote));
2280 			if (iremote.name_len == 0 ||
2281 			    iremote.fetch_url_len == 0 ||
2282 			    iremote.send_url_len == 0 ||
2283 			    (sizeof(iremote) + iremote.name_len +
2284 			    iremote.fetch_url_len + iremote.send_url_len) > datalen) {
2285 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2286 				break;
2287 			}
2288 			remote->name = strndup(imsg.data + sizeof(iremote),
2289 			    iremote.name_len);
2290 			if (remote->name == NULL) {
2291 				err = got_error_from_errno("strndup");
2292 				break;
2293 			}
2294 			remote->fetch_url = strndup(imsg.data + sizeof(iremote) +
2295 			    iremote.name_len, iremote.fetch_url_len);
2296 			if (remote->fetch_url == NULL) {
2297 				err = got_error_from_errno("strndup");
2298 				free_remote_data(remote);
2299 				break;
2300 			}
2301 			remote->send_url = strndup(imsg.data + sizeof(iremote) +
2302 			    iremote.name_len + iremote.fetch_url_len,
2303 			    iremote.send_url_len);
2304 			if (remote->send_url == NULL) {
2305 				err = got_error_from_errno("strndup");
2306 				free_remote_data(remote);
2307 				break;
2308 			}
2309 			remote->mirror_references = iremote.mirror_references;
2310 			remote->fetch_all_branches = iremote.fetch_all_branches;
2311 			remote->nfetch_branches = 0;
2312 			remote->fetch_branches = NULL;
2313 			remote->nsend_branches = 0;
2314 			remote->send_branches = NULL;
2315 			remote->nfetch_refs = 0;
2316 			remote->fetch_refs = NULL;
2317 			(*nremotes)++;
2318 			break;
2319 		default:
2320 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2321 			break;
2322 		}
2323 
2324 		imsg_free(&imsg);
2325 		if (err)
2326 			break;
2327 	}
2328 
2329 	if (err) {
2330 		int i;
2331 		for (i = 0; i < *nremotes; i++)
2332 			free_remote_data(&(*remotes)[i]);
2333 		free(*remotes);
2334 		*remotes = NULL;
2335 		*nremotes = 0;
2336 	}
2337 	return err;
2338 }
2339 
2340 const struct got_error *
2341 got_privsep_send_gotconfig_parse_req(struct imsgbuf *ibuf, int fd)
2342 {
2343 	const struct got_error *err = NULL;
2344 
2345 	if (imsg_compose(ibuf, GOT_IMSG_GOTCONFIG_PARSE_REQUEST, 0, 0, fd,
2346 	    NULL, 0) == -1) {
2347 		err = got_error_from_errno("imsg_compose "
2348 		    "GOTCONFIG_PARSE_REQUEST");
2349 		close(fd);
2350 		return err;
2351 	}
2352 
2353 	return flush_imsg(ibuf);
2354 }
2355 
2356 const struct got_error *
2357 got_privsep_send_gotconfig_author_req(struct imsgbuf *ibuf)
2358 {
2359 	if (imsg_compose(ibuf,
2360 	    GOT_IMSG_GOTCONFIG_AUTHOR_REQUEST, 0, 0, -1, NULL, 0) == -1)
2361 		return got_error_from_errno("imsg_compose "
2362 		    "GOTCONFIG_AUTHOR_REQUEST");
2363 
2364 	return flush_imsg(ibuf);
2365 }
2366 
2367 const struct got_error *
2368 got_privsep_send_gotconfig_allowed_signers_req(struct imsgbuf *ibuf)
2369 {
2370 	if (imsg_compose(ibuf,
2371 	    GOT_IMSG_GOTCONFIG_ALLOWEDSIGNERS_REQUEST, 0, 0, -1, NULL, 0) == -1)
2372 		return got_error_from_errno("imsg_compose "
2373 		    "GOTCONFIG_ALLOWEDSIGNERS_REQUEST");
2374 
2375 	return flush_imsg(ibuf);
2376 }
2377 
2378 const struct got_error *
2379 got_privsep_send_gotconfig_revoked_signers_req(struct imsgbuf *ibuf)
2380 {
2381 	if (imsg_compose(ibuf,
2382 	    GOT_IMSG_GOTCONFIG_REVOKEDSIGNERS_REQUEST, 0, 0, -1, NULL, 0) == -1)
2383 		return got_error_from_errno("imsg_compose "
2384 		    "GOTCONFIG_REVOKEDSIGNERS_REQUEST");
2385 
2386 	return flush_imsg(ibuf);
2387 }
2388 
2389 const struct got_error *
2390 got_privsep_send_gotconfig_remotes_req(struct imsgbuf *ibuf)
2391 {
2392 	if (imsg_compose(ibuf,
2393 	    GOT_IMSG_GOTCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2394 		return got_error_from_errno("imsg_compose "
2395 		    "GOTCONFIG_REMOTE_REQUEST");
2396 
2397 	return flush_imsg(ibuf);
2398 }
2399 
2400 const struct got_error *
2401 got_privsep_recv_gotconfig_str(char **str, struct imsgbuf *ibuf)
2402 {
2403 	const struct got_error *err = NULL;
2404 	struct imsg imsg;
2405 	size_t datalen;
2406 
2407 	*str = NULL;
2408 
2409 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2410 	if (err)
2411 		return err;
2412 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2413 
2414 	switch (imsg.hdr.type) {
2415 	case GOT_IMSG_ERROR:
2416 		err = recv_imsg_error(&imsg, datalen);
2417 		break;
2418 	case GOT_IMSG_GOTCONFIG_STR_VAL:
2419 		if (datalen == 0)
2420 			break;
2421 		/* datalen does not include terminating \0 */
2422 		*str = malloc(datalen + 1);
2423 		if (*str == NULL) {
2424 			err = got_error_from_errno("malloc");
2425 			break;
2426 		}
2427 		memcpy(*str, imsg.data, datalen);
2428 		(*str)[datalen] = '\0';
2429 		break;
2430 	default:
2431 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2432 		break;
2433 	}
2434 
2435 	imsg_free(&imsg);
2436 	return err;
2437 }
2438 
2439 const struct got_error *
2440 got_privsep_recv_gotconfig_remotes(struct got_remote_repo **remotes,
2441     int *nremotes, struct imsgbuf *ibuf)
2442 {
2443 	const struct got_error *err = NULL;
2444 	struct imsg imsg;
2445 	size_t datalen;
2446 	struct got_imsg_remotes iremotes;
2447 	struct got_imsg_remote iremote;
2448 	const size_t min_datalen =
2449 	    MIN(sizeof(struct got_imsg_error), sizeof(iremotes));
2450 
2451 	*remotes = NULL;
2452 	*nremotes = 0;
2453 	iremotes.nremotes = 0;
2454 
2455 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2456 	if (err)
2457 		return err;
2458 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2459 
2460 	switch (imsg.hdr.type) {
2461 	case GOT_IMSG_ERROR:
2462 		err = recv_imsg_error(&imsg, datalen);
2463 		break;
2464 	case GOT_IMSG_GOTCONFIG_REMOTES:
2465 		if (datalen != sizeof(iremotes)) {
2466 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2467 			break;
2468 		}
2469 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2470 		if (iremotes.nremotes < 0) {
2471 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2472 			break;
2473 		}
2474 		if (iremotes.nremotes == 0) {
2475 			imsg_free(&imsg);
2476 			return NULL;
2477 		}
2478 		break;
2479 	default:
2480 		imsg_free(&imsg);
2481 		return got_error(GOT_ERR_PRIVSEP_MSG);
2482 	}
2483 
2484 	imsg_free(&imsg);
2485 
2486 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2487 	if (*remotes == NULL)
2488 		return got_error_from_errno("recallocarray");
2489 
2490 	while (*nremotes < iremotes.nremotes) {
2491 		struct got_remote_repo *remote;
2492 		const size_t min_datalen =
2493 		    MIN(sizeof(struct got_imsg_error), sizeof(iremote));
2494 		int i;
2495 
2496 		err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2497 		if (err)
2498 			break;
2499 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2500 
2501 		switch (imsg.hdr.type) {
2502 		case GOT_IMSG_ERROR:
2503 			err = recv_imsg_error(&imsg, datalen);
2504 			break;
2505 		case GOT_IMSG_GOTCONFIG_REMOTE:
2506 			remote = &(*remotes)[*nremotes];
2507 			memset(remote, 0, sizeof(*remote));
2508 			if (datalen < sizeof(iremote)) {
2509 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2510 				break;
2511 			}
2512 			memcpy(&iremote, imsg.data, sizeof(iremote));
2513 			if (iremote.name_len == 0 ||
2514 			    (iremote.fetch_url_len == 0 &&
2515 			    iremote.send_url_len == 0) ||
2516 			    (sizeof(iremote) + iremote.name_len +
2517 			    iremote.fetch_url_len + iremote.send_url_len) >
2518 			    datalen) {
2519 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2520 				break;
2521 			}
2522 			remote->name = strndup(imsg.data + sizeof(iremote),
2523 			    iremote.name_len);
2524 			if (remote->name == NULL) {
2525 				err = got_error_from_errno("strndup");
2526 				break;
2527 			}
2528 			remote->fetch_url = strndup(imsg.data +
2529 			    sizeof(iremote) + iremote.name_len,
2530 			    iremote.fetch_url_len);
2531 			if (remote->fetch_url == NULL) {
2532 				err = got_error_from_errno("strndup");
2533 				free_remote_data(remote);
2534 				break;
2535 			}
2536 			remote->send_url = strndup(imsg.data +
2537 			    sizeof(iremote) + iremote.name_len +
2538 			    iremote.fetch_url_len, iremote.send_url_len);
2539 			if (remote->send_url == NULL) {
2540 				err = got_error_from_errno("strndup");
2541 				free_remote_data(remote);
2542 				break;
2543 			}
2544 			remote->mirror_references = iremote.mirror_references;
2545 			remote->fetch_all_branches = iremote.fetch_all_branches;
2546 			if (iremote.nfetch_branches > 0) {
2547 				remote->fetch_branches = recallocarray(NULL, 0,
2548 				    iremote.nfetch_branches, sizeof(char *));
2549 				if (remote->fetch_branches == NULL) {
2550 					err = got_error_from_errno("calloc");
2551 					free_remote_data(remote);
2552 					break;
2553 				}
2554 			}
2555 			remote->nfetch_branches = 0;
2556 			for (i = 0; i < iremote.nfetch_branches; i++) {
2557 				char *branch;
2558 				err = got_privsep_recv_gotconfig_str(&branch,
2559 				    ibuf);
2560 				if (err) {
2561 					free_remote_data(remote);
2562 					goto done;
2563 				}
2564 				remote->fetch_branches[i] = branch;
2565 				remote->nfetch_branches++;
2566 			}
2567 			if (iremote.nsend_branches > 0) {
2568 				remote->send_branches = recallocarray(NULL, 0,
2569 				    iremote.nsend_branches, sizeof(char *));
2570 				if (remote->send_branches == NULL) {
2571 					err = got_error_from_errno("calloc");
2572 					free_remote_data(remote);
2573 					break;
2574 				}
2575 			}
2576 			remote->nsend_branches = 0;
2577 			for (i = 0; i < iremote.nsend_branches; i++) {
2578 				char *branch;
2579 				err = got_privsep_recv_gotconfig_str(&branch,
2580 				    ibuf);
2581 				if (err) {
2582 					free_remote_data(remote);
2583 					goto done;
2584 				}
2585 				remote->send_branches[i] = branch;
2586 				remote->nsend_branches++;
2587 			}
2588 			if (iremote.nfetch_refs > 0) {
2589 				remote->fetch_refs = recallocarray(NULL, 0,
2590 				    iremote.nfetch_refs, sizeof(char *));
2591 				if (remote->fetch_refs == NULL) {
2592 					err = got_error_from_errno("calloc");
2593 					free_remote_data(remote);
2594 					break;
2595 				}
2596 			}
2597 			remote->nfetch_refs = 0;
2598 			for (i = 0; i < iremote.nfetch_refs; i++) {
2599 				char *ref;
2600 				err = got_privsep_recv_gotconfig_str(&ref,
2601 				    ibuf);
2602 				if (err) {
2603 					free_remote_data(remote);
2604 					goto done;
2605 				}
2606 				remote->fetch_refs[i] = ref;
2607 				remote->nfetch_refs++;
2608 			}
2609 			(*nremotes)++;
2610 			break;
2611 		default:
2612 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2613 			break;
2614 		}
2615 
2616 		imsg_free(&imsg);
2617 		if (err)
2618 			break;
2619 	}
2620 done:
2621 	if (err) {
2622 		int i;
2623 		for (i = 0; i < *nremotes; i++)
2624 			free_remote_data(&(*remotes)[i]);
2625 		free(*remotes);
2626 		*remotes = NULL;
2627 		*nremotes = 0;
2628 	}
2629 	return err;
2630 }
2631 
2632 const struct got_error *
2633 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
2634     struct got_object_id *id, int idx, const char *path)
2635 {
2636 	struct ibuf *wbuf;
2637 	size_t path_len = strlen(path) + 1;
2638 
2639 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
2640 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
2641 	if (wbuf == NULL)
2642 		return got_error_from_errno(
2643 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
2644 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1)
2645 		return got_error_from_errno("imsg_add "
2646 		    "COMMIT_TRAVERSAL_REQUEST");
2647 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1)
2648 		return got_error_from_errno("imsg_add "
2649 		    "COMMIT_TRAVERSAL_REQUEST");
2650 	if (imsg_add(wbuf, path, path_len) == -1)
2651 		return got_error_from_errno("imsg_add "
2652 		    "COMMIT_TRAVERSAL_REQUEST");
2653 
2654 	wbuf->fd = -1;
2655 	imsg_close(ibuf, wbuf);
2656 
2657 	return flush_imsg(ibuf);
2658 }
2659 
2660 const struct got_error *
2661 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
2662     struct got_object_id **changed_commit_id,
2663     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
2664 {
2665 	const struct got_error *err = NULL;
2666 	struct imsg imsg;
2667 	struct got_imsg_traversed_commits *icommits;
2668 	size_t datalen;
2669 	int i, done = 0;
2670 
2671 	*changed_commit = NULL;
2672 	*changed_commit_id = NULL;
2673 
2674 	while (!done) {
2675 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2676 		if (err)
2677 			return err;
2678 
2679 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2680 		switch (imsg.hdr.type) {
2681 		case GOT_IMSG_TRAVERSED_COMMITS:
2682 			icommits = imsg.data;
2683 			if (datalen != sizeof(*icommits) +
2684 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
2685 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2686 				break;
2687 			}
2688 			for (i = 0; i < icommits->ncommits; i++) {
2689 				struct got_object_qid *qid;
2690 				uint8_t *sha1 = (uint8_t *)imsg.data +
2691 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
2692 				err = got_object_qid_alloc_partial(&qid);
2693 				if (err)
2694 					break;
2695 				memcpy(qid->id.sha1, sha1, SHA1_DIGEST_LENGTH);
2696 				STAILQ_INSERT_TAIL(commit_ids, qid, entry);
2697 
2698 				/* The last commit may contain a change. */
2699 				if (i == icommits->ncommits - 1) {
2700 					*changed_commit_id =
2701 					    got_object_id_dup(&qid->id);
2702 					if (*changed_commit_id == NULL) {
2703 						err = got_error_from_errno(
2704 						    "got_object_id_dup");
2705 						break;
2706 					}
2707 				}
2708 			}
2709 			break;
2710 		case GOT_IMSG_COMMIT:
2711 			if (*changed_commit_id == NULL) {
2712 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2713 				break;
2714 			}
2715 			err = get_commit_from_imsg(changed_commit, &imsg,
2716 			    datalen, ibuf);
2717 			break;
2718 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
2719 			done = 1;
2720 			break;
2721 		default:
2722 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2723 			break;
2724 		}
2725 
2726 		imsg_free(&imsg);
2727 		if (err)
2728 			break;
2729 	}
2730 
2731 	if (err)
2732 		got_object_id_queue_free(commit_ids);
2733 	return err;
2734 }
2735 
2736 const struct got_error *
2737 got_privsep_send_enumerated_tree(size_t *totlen, struct imsgbuf *ibuf,
2738     struct got_object_id *tree_id, const char *path,
2739     struct got_parsed_tree_entry *entries, int nentries)
2740 {
2741 	const struct got_error *err = NULL;
2742 	struct ibuf *wbuf;
2743 	size_t path_len = strlen(path);
2744 	size_t msglen;
2745 
2746 	msglen = sizeof(struct got_imsg_enumerated_tree) + path_len;
2747 	wbuf = imsg_create(ibuf, GOT_IMSG_ENUMERATED_TREE, 0, 0, msglen);
2748 	if (wbuf == NULL)
2749 		return got_error_from_errno("imsg_create ENUMERATED_TREE");
2750 
2751 	if (imsg_add(wbuf, tree_id->sha1, SHA1_DIGEST_LENGTH) == -1)
2752 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2753 	if (imsg_add(wbuf, &nentries, sizeof(nentries)) == -1)
2754 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2755 	if (imsg_add(wbuf, path, path_len) == -1)
2756 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2757 
2758 	wbuf->fd = -1;
2759 	imsg_close(ibuf, wbuf);
2760 
2761 	if (entries) {
2762 		err = send_tree_entries(ibuf, entries, nentries);
2763 		if (err)
2764 			return err;
2765 	}
2766 
2767 	return flush_imsg(ibuf);
2768 }
2769 
2770 const struct got_error *
2771 got_privsep_send_object_enumeration_request(struct imsgbuf *ibuf)
2772 {
2773 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_REQUEST,
2774 	    0, 0, -1, NULL, 0) == -1)
2775 		return got_error_from_errno("imsg_compose "
2776 		    "OBJECT_ENUMERATION_REQUEST");
2777 
2778 	return flush_imsg(ibuf);
2779 }
2780 
2781 const struct got_error *
2782 got_privsep_send_object_enumeration_done(struct imsgbuf *ibuf)
2783 {
2784 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_DONE,
2785 	    0, 0, -1, NULL, 0) == -1)
2786 		return got_error_from_errno("imsg_compose "
2787 		    "OBJECT_ENUMERATION_DONE");
2788 
2789 	return flush_imsg(ibuf);
2790 }
2791 
2792 const struct got_error *
2793 got_privsep_send_object_enumeration_incomplete(struct imsgbuf *ibuf)
2794 {
2795 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_INCOMPLETE,
2796 	    0, 0, -1, NULL, 0) == -1)
2797 		return got_error_from_errno("imsg_compose "
2798 		    "OBJECT_ENUMERATION_INCOMPLETE");
2799 
2800 	return flush_imsg(ibuf);
2801 }
2802 
2803 const struct got_error *
2804 got_privsep_send_enumerated_commit(struct imsgbuf *ibuf,
2805     struct got_object_id *id, time_t mtime)
2806 {
2807 	struct ibuf *wbuf;
2808 
2809 	wbuf = imsg_create(ibuf, GOT_IMSG_ENUMERATED_COMMIT, 0, 0,
2810 	    sizeof(struct got_imsg_enumerated_commit) + SHA1_DIGEST_LENGTH);
2811 	if (wbuf == NULL)
2812 		return got_error_from_errno("imsg_create ENUMERATED_COMMIT");
2813 
2814 	/* Keep in sync with struct got_imsg_enumerated_commit! */
2815 	if (imsg_add(wbuf, id, SHA1_DIGEST_LENGTH) == -1)
2816 		return got_error_from_errno("imsg_add ENUMERATED_COMMIT");
2817 	if (imsg_add(wbuf, &mtime, sizeof(mtime)) == -1)
2818 		return got_error_from_errno("imsg_add ENUMERATED_COMMIT");
2819 
2820 	wbuf->fd = -1;
2821 	imsg_close(ibuf, wbuf);
2822 	/* Don't flush yet, tree entries or ENUMERATION_DONE will follow. */
2823 	return NULL;
2824 }
2825 
2826 const struct got_error *
2827 got_privsep_recv_enumerated_objects(int *found_all_objects,
2828     struct imsgbuf *ibuf,
2829     got_object_enumerate_commit_cb cb_commit,
2830     got_object_enumerate_tree_cb cb_tree, void *cb_arg,
2831     struct got_repository *repo)
2832 {
2833 	const struct got_error *err = NULL;
2834 	struct imsg imsg;
2835 	struct got_imsg_enumerated_commit *icommit = NULL;
2836 	struct got_object_id commit_id;
2837 	int have_commit = 0;
2838 	time_t mtime = 0;
2839 	struct got_tree_object tree;
2840 	struct got_imsg_enumerated_tree *itree;
2841 	struct got_object_id tree_id;
2842 	char *path = NULL, *canon_path = NULL;
2843 	size_t datalen, path_len;
2844 	int nentries = -1;
2845 	int done = 0;
2846 
2847 	*found_all_objects = 0;
2848 	memset(&tree, 0, sizeof(tree));
2849 
2850 	while (!done) {
2851 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2852 		if (err)
2853 			break;
2854 
2855 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2856 		switch (imsg.hdr.type) {
2857 		case GOT_IMSG_ENUMERATED_COMMIT:
2858 			if (have_commit && nentries != -1) {
2859 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2860 				break;
2861 			}
2862 			if (datalen != sizeof(*icommit)) {
2863 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2864 				break;
2865 			}
2866 			icommit = (struct got_imsg_enumerated_commit *)imsg.data;
2867 			memcpy(commit_id.sha1, icommit->id, SHA1_DIGEST_LENGTH);
2868 			mtime = icommit->mtime;
2869 			have_commit = 1;
2870 			break;
2871 		case GOT_IMSG_ENUMERATED_TREE:
2872 			/* Should be preceeded by GOT_IMSG_ENUMERATED_COMMIT. */
2873 			if (!have_commit) {
2874 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2875 				break;
2876 			}
2877 			if (datalen < sizeof(*itree)) {
2878 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2879 				break;
2880 			}
2881 			itree = imsg.data;
2882 			path_len = datalen - sizeof(*itree);
2883 			if (path_len == 0) {
2884 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2885 				break;
2886 			}
2887 			memcpy(tree_id.sha1, itree->id, sizeof(tree_id.sha1));
2888 			free(path);
2889 			path = malloc(path_len + 1);
2890 			if (path == NULL) {
2891 				err = got_error_from_errno("malloc");
2892 				break;
2893 			}
2894 			free(canon_path);
2895 			canon_path = malloc(path_len + 1);
2896 			if (canon_path == NULL) {
2897 				err = got_error_from_errno("malloc");
2898 				break;
2899 			}
2900 			memcpy(path, (uint8_t *)imsg.data + sizeof(*itree),
2901 			    path_len);
2902 			path[path_len] = '\0';
2903 			if (!got_path_is_absolute(path)) {
2904 				err = got_error(GOT_ERR_BAD_PATH);
2905 				break;
2906 			}
2907 			if (got_path_is_root_dir(path)) {
2908 				/* XXX check what got_canonpath() does wrong */
2909 				canon_path[0] = '/';
2910 				canon_path[1] = '\0';
2911 			} else {
2912 				err = got_canonpath(path, canon_path,
2913 				    path_len + 1);
2914 				if (err)
2915 					break;
2916 			}
2917 			if (strcmp(path, canon_path) != 0) {
2918 				err = got_error(GOT_ERR_BAD_PATH);
2919 				break;
2920 			}
2921 			if (nentries != -1) {
2922 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2923 				break;
2924 			}
2925 			if (itree->nentries < -1) {
2926 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2927 				break;
2928 			}
2929 			if (itree->nentries == -1) {
2930 				/* Tree was not found in pack file. */
2931 				err = cb_tree(cb_arg, NULL, mtime, &tree_id,
2932 				    path, repo);
2933 				break;
2934 			}
2935 			if (itree->nentries > INT_MAX) {
2936 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2937 				break;
2938 			}
2939 			tree.entries = calloc(itree->nentries,
2940 			    sizeof(struct got_tree_entry));
2941 			if (tree.entries == NULL) {
2942 				err = got_error_from_errno("calloc");
2943 				break;
2944 			}
2945 			if (itree->nentries == 0) {
2946 				err = cb_tree(cb_arg, &tree, mtime, &tree_id,
2947 				    path, repo);
2948 				if (err)
2949 					break;
2950 
2951 				/* Prepare for next tree. */
2952 				free(tree.entries);
2953 				memset(&tree, 0, sizeof(tree));
2954 				nentries = -1;
2955 			} else {
2956 				tree.nentries = itree->nentries;
2957 				nentries = 0;
2958 			}
2959 			break;
2960 		case GOT_IMSG_TREE_ENTRIES:
2961 			/* Should be preceeded by GOT_IMSG_ENUMERATED_TREE. */
2962 			if (nentries <= -1) {
2963 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2964 				break;
2965 			}
2966 			err = recv_tree_entries(imsg.data, datalen,
2967 			    &tree, &nentries);
2968 			if (err)
2969 				break;
2970 			if (tree.nentries == nentries) {
2971 				err = cb_tree(cb_arg, &tree, mtime, &tree_id,
2972 				    path, repo);
2973 				if (err)
2974 					break;
2975 
2976 				/* Prepare for next tree. */
2977 				free(tree.entries);
2978 				memset(&tree, 0, sizeof(tree));
2979 				nentries = -1;
2980 			}
2981 			break;
2982 		case GOT_IMSG_TREE_ENUMERATION_DONE:
2983 			/* All trees have been found and traversed. */
2984 			if (!have_commit || path == NULL || nentries != -1) {
2985 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2986 				break;
2987 			}
2988 			err = cb_commit(cb_arg, mtime, &commit_id, repo);
2989 			if (err)
2990 				break;
2991 			have_commit = 0;
2992 			break;
2993 		case GOT_IMSG_OBJECT_ENUMERATION_DONE:
2994 			*found_all_objects = 1;
2995 			done = 1;
2996 			break;
2997 		case GOT_IMSG_OBJECT_ENUMERATION_INCOMPLETE:
2998 			done = 1;
2999 			break;
3000 		default:
3001 			err = got_error(GOT_ERR_PRIVSEP_MSG);
3002 			break;
3003 		}
3004 
3005 		imsg_free(&imsg);
3006 		if (err)
3007 			break;
3008 	}
3009 
3010 	free(path);
3011 	free(canon_path);
3012 	free(tree.entries);
3013 	return err;
3014 }
3015 
3016 const struct got_error *
3017 got_privsep_send_raw_delta_req(struct imsgbuf *ibuf, int idx,
3018     struct got_object_id *id)
3019 {
3020 	struct got_imsg_raw_delta_request dreq;
3021 
3022 	memset(&dreq, 0, sizeof(dreq));
3023 	dreq.idx = idx;
3024 	memcpy(dreq.id, id->sha1, SHA1_DIGEST_LENGTH);
3025 
3026 	if (imsg_compose(ibuf, GOT_IMSG_RAW_DELTA_REQUEST, 0, 0, -1,
3027 	    &dreq, sizeof(dreq)) == -1)
3028 		return got_error_from_errno("imsg_compose RAW_DELTA_REQUEST");
3029 
3030 	return flush_imsg(ibuf);
3031 }
3032 
3033 const struct got_error *
3034 got_privsep_send_raw_delta_outfd(struct imsgbuf *ibuf, int fd)
3035 {
3036 	return send_fd(ibuf, GOT_IMSG_RAW_DELTA_OUTFD, fd);
3037 }
3038 
3039 const struct got_error *
3040 got_privsep_send_raw_delta(struct imsgbuf *ibuf, uint64_t base_size,
3041     uint64_t result_size,  off_t delta_size, off_t delta_compressed_size,
3042     off_t delta_offset, off_t delta_out_offset, struct got_object_id *base_id)
3043 {
3044 	struct got_imsg_raw_delta idelta;
3045 	int ret;
3046 
3047 	memset(&idelta, 0, sizeof(idelta));
3048 	idelta.base_size = base_size;
3049 	idelta.result_size = result_size;
3050 	idelta.delta_size = delta_size;
3051 	idelta.delta_compressed_size = delta_compressed_size;
3052 	idelta.delta_offset = delta_offset;
3053 	idelta.delta_out_offset = delta_out_offset;
3054 	memcpy(idelta.base_id, base_id->sha1, SHA1_DIGEST_LENGTH);
3055 
3056 	ret = imsg_compose(ibuf, GOT_IMSG_RAW_DELTA, 0, 0, -1,
3057 	    &idelta, sizeof(idelta));
3058 	if (ret == -1)
3059 		return got_error_from_errno("imsg_compose RAW_DELTA");
3060 
3061 	return flush_imsg(ibuf);
3062 }
3063 
3064 const struct got_error *
3065 got_privsep_recv_raw_delta(uint64_t *base_size, uint64_t *result_size,
3066     off_t *delta_size, off_t *delta_compressed_size, off_t *delta_offset,
3067     off_t *delta_out_offset, struct got_object_id **base_id, struct imsgbuf *ibuf)
3068 {
3069 	const struct got_error *err = NULL;
3070 	struct imsg imsg;
3071 	struct got_imsg_raw_delta *delta;
3072 	size_t datalen;
3073 
3074 	*base_size = 0;
3075 	*result_size = 0;
3076 	*delta_size = 0;
3077 	*delta_compressed_size = 0;
3078 	*delta_offset = 0;
3079 	*delta_out_offset = 0;
3080 	*base_id = NULL;
3081 
3082 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3083 	if (err)
3084 		return err;
3085 
3086 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3087 
3088 	switch (imsg.hdr.type) {
3089 	case GOT_IMSG_RAW_DELTA:
3090 		if (datalen != sizeof(*delta)) {
3091 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3092 			break;
3093 		}
3094 		delta = imsg.data;
3095 		*base_size = delta->base_size;
3096 		*result_size = delta->result_size;
3097 		*delta_size = delta->delta_size;
3098 		*delta_compressed_size = delta->delta_compressed_size;
3099 		*delta_offset = delta->delta_offset;
3100 		*delta_out_offset = delta->delta_out_offset;
3101 		*base_id = calloc(1, sizeof(**base_id));
3102 		if (*base_id == NULL) {
3103 			err = got_error_from_errno("malloc");
3104 			break;
3105 		}
3106 		memcpy((*base_id)->sha1, delta->base_id, SHA1_DIGEST_LENGTH);
3107 		break;
3108 	default:
3109 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3110 		break;
3111 	}
3112 
3113 	imsg_free(&imsg);
3114 
3115 	if (err) {
3116 		free(*base_id);
3117 		*base_id = NULL;
3118 	}
3119 	return err;
3120 }
3121 
3122 static const struct got_error *
3123 send_idlist(struct imsgbuf *ibuf, struct got_object_id **ids, size_t nids)
3124 {
3125 	const struct got_error *err = NULL;
3126 	struct got_imsg_object_idlist idlist;
3127 	struct ibuf *wbuf;
3128 	size_t i;
3129 
3130 	memset(&idlist, 0, sizeof(idlist));
3131 
3132 	if (nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS)
3133 		return got_error(GOT_ERR_NO_SPACE);
3134 
3135 	wbuf = imsg_create(ibuf, GOT_IMSG_OBJ_ID_LIST, 0, 0,
3136 	    sizeof(idlist) + nids * sizeof(**ids));
3137 	if (wbuf == NULL) {
3138 		err = got_error_from_errno("imsg_create OBJ_ID_LIST");
3139 		return err;
3140 	}
3141 
3142 	idlist.nids = nids;
3143 	if (imsg_add(wbuf, &idlist, sizeof(idlist)) == -1)
3144 		return got_error_from_errno("imsg_add OBJ_ID_LIST");
3145 
3146 	for (i = 0; i < nids; i++) {
3147 		struct got_object_id *id = ids[i];
3148 		if (imsg_add(wbuf, id, sizeof(*id)) == -1)
3149 			return got_error_from_errno("imsg_add OBJ_ID_LIST");
3150 	}
3151 
3152 	wbuf->fd = -1;
3153 	imsg_close(ibuf, wbuf);
3154 
3155 	return flush_imsg(ibuf);
3156 }
3157 
3158 const struct got_error *
3159 got_privsep_send_object_idlist(struct imsgbuf *ibuf,
3160     struct got_object_id **ids, size_t nids)
3161 {
3162 	const struct got_error *err = NULL;
3163 	struct got_object_id *idlist[GOT_IMSG_OBJ_ID_LIST_MAX_NIDS];
3164 	int i, queued = 0;
3165 
3166 	for (i = 0; i < nids; i++) {
3167 		idlist[i % nitems(idlist)] = ids[i];
3168 		queued++;
3169 		if (queued >= nitems(idlist)) {
3170 			err = send_idlist(ibuf, idlist, queued);
3171 			if (err)
3172 				return err;
3173 			queued = 0;
3174 		}
3175 	}
3176 
3177 	if (queued > 0) {
3178 		err = send_idlist(ibuf, idlist, queued);
3179 		if (err)
3180 			return err;
3181 	}
3182 
3183 	return NULL;
3184 }
3185 
3186 const struct got_error *
3187 got_privsep_send_object_idlist_done(struct imsgbuf *ibuf)
3188 {
3189 	if (imsg_compose(ibuf, GOT_IMSG_OBJ_ID_LIST_DONE, 0, 0, -1, NULL, 0)
3190 	    == -1)
3191 		return got_error_from_errno("imsg_compose OBJ_ID_LIST_DONE");
3192 
3193 	return flush_imsg(ibuf);
3194 }
3195 
3196 const struct got_error *
3197 got_privsep_recv_object_idlist(int *done, struct got_object_id **ids,
3198     size_t *nids, struct imsgbuf *ibuf)
3199 {
3200 	const struct got_error *err = NULL;
3201 	struct imsg imsg;
3202 	struct got_imsg_object_idlist *idlist;
3203 	size_t datalen;
3204 
3205 	*ids = NULL;
3206 	*done = 0;
3207 	*nids = 0;
3208 
3209 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3210 	if (err)
3211 		return err;
3212 
3213 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3214 	switch (imsg.hdr.type) {
3215 	case GOT_IMSG_OBJ_ID_LIST:
3216 		if (datalen < sizeof(*idlist)) {
3217 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3218 			break;
3219 		}
3220 		idlist = imsg.data;
3221 		if (idlist->nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS ||
3222 		    idlist->nids * sizeof(**ids) > datalen - sizeof(*idlist)) {
3223 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3224 			break;
3225 		}
3226 		*nids = idlist->nids;
3227 		*ids = calloc(*nids, sizeof(**ids));
3228 		if (*ids == NULL) {
3229 			err = got_error_from_errno("calloc");
3230 			break;
3231 		}
3232 		memcpy(*ids, (uint8_t *)imsg.data + sizeof(*idlist),
3233 		    *nids * sizeof(**ids));
3234 		break;
3235 	case GOT_IMSG_OBJ_ID_LIST_DONE:
3236 		*done = 1;
3237 		break;
3238 	default:
3239 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3240 		break;
3241 	}
3242 
3243 	imsg_free(&imsg);
3244 
3245 	return err;
3246 }
3247 
3248 const struct got_error *
3249 got_privsep_send_delta_reuse_req(struct imsgbuf *ibuf)
3250 {
3251 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_REQUEST, 0, 0, -1, NULL, 0)
3252 	    == -1)
3253 		return got_error_from_errno("imsg_compose DELTA_REUSE_REQUEST");
3254 
3255 	return flush_imsg(ibuf);
3256 }
3257 
3258 const struct got_error *
3259 got_privsep_send_reused_deltas(struct imsgbuf *ibuf,
3260     struct got_imsg_reused_delta *deltas, size_t ndeltas)
3261 {
3262 	const struct got_error *err = NULL;
3263 	struct ibuf *wbuf;
3264 	struct got_imsg_reused_deltas ideltas;
3265 	size_t i;
3266 
3267 	memset(&ideltas, 0, sizeof(ideltas));
3268 
3269 	if (ndeltas > GOT_IMSG_REUSED_DELTAS_MAX_NDELTAS)
3270 		return got_error(GOT_ERR_NO_SPACE);
3271 
3272 	wbuf = imsg_create(ibuf, GOT_IMSG_REUSED_DELTAS, 0, 0,
3273 	    sizeof(ideltas) + ndeltas * sizeof(*deltas));
3274 	if (wbuf == NULL) {
3275 		err = got_error_from_errno("imsg_create REUSED_DELTAS");
3276 		return err;
3277 	}
3278 
3279 	ideltas.ndeltas = ndeltas;
3280 	if (imsg_add(wbuf, &ideltas, sizeof(ideltas)) == -1)
3281 		return got_error_from_errno("imsg_add REUSED_DELTAS");
3282 
3283 	for (i = 0; i < ndeltas; i++) {
3284 		struct got_imsg_reused_delta *delta = &deltas[i];
3285 		if (imsg_add(wbuf, delta, sizeof(*delta)) == -1)
3286 			return got_error_from_errno("imsg_add REUSED_DELTAS");
3287 	}
3288 
3289 	wbuf->fd = -1;
3290 	imsg_close(ibuf, wbuf);
3291 
3292 	return flush_imsg(ibuf);
3293 }
3294 
3295 const struct got_error *
3296 got_privsep_send_reused_deltas_done(struct imsgbuf *ibuf)
3297 {
3298 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_DONE, 0, 0, -1, NULL, 0)
3299 	    == -1)
3300 		return got_error_from_errno("imsg_compose DELTA_REUSE_DONE");
3301 
3302 	return flush_imsg(ibuf);
3303 }
3304 
3305 const struct got_error *
3306 got_privsep_recv_reused_deltas(int *done, struct got_imsg_reused_delta *deltas,
3307     size_t *ndeltas, struct imsgbuf *ibuf)
3308 {
3309 	const struct got_error *err = NULL;
3310 	struct imsg imsg;
3311 	struct got_imsg_reused_deltas *ideltas;
3312 	size_t datalen;
3313 
3314 	*done = 0;
3315 	*ndeltas = 0;
3316 
3317 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3318 	if (err)
3319 		return err;
3320 
3321 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3322 	switch (imsg.hdr.type) {
3323 	case GOT_IMSG_REUSED_DELTAS:
3324 		if (datalen < sizeof(*ideltas)) {
3325 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3326 			break;
3327 		}
3328 		ideltas = imsg.data;
3329 		if (ideltas->ndeltas > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS ||
3330 		    ideltas->ndeltas * sizeof(*deltas) >
3331 		    datalen - sizeof(*ideltas)) {
3332 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3333 			break;
3334 		}
3335 		*ndeltas = ideltas->ndeltas;
3336 		memcpy(deltas, (uint8_t *)imsg.data + sizeof(*ideltas),
3337 		    *ndeltas * sizeof(*deltas));
3338 		break;
3339 	case GOT_IMSG_DELTA_REUSE_DONE:
3340 		*done = 1;
3341 		break;
3342 	default:
3343 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3344 		break;
3345 	}
3346 
3347 	imsg_free(&imsg);
3348 
3349 	return err;
3350 }
3351 
3352 const struct got_error *
3353 got_privsep_init_commit_painting(struct imsgbuf *ibuf)
3354 {
3355 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_PAINTING_INIT,
3356 	    0, 0, -1, NULL, 0)
3357 	    == -1)
3358 		return got_error_from_errno("imsg_compose "
3359 		    "COMMIT_PAINTING_INIT");
3360 
3361 	return flush_imsg(ibuf);
3362 }
3363 
3364 const struct got_error *
3365 got_privsep_send_painting_request(struct imsgbuf *ibuf, int idx,
3366     struct got_object_id *id, intptr_t color)
3367 {
3368 	struct got_imsg_commit_painting_request ireq;
3369 
3370 	memset(&ireq, 0, sizeof(ireq));
3371 	memcpy(ireq.id, id->sha1, sizeof(ireq.id));
3372 	ireq.idx = idx;
3373 	ireq.color = color;
3374 
3375 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_PAINTING_REQUEST, 0, 0, -1,
3376 	    &ireq, sizeof(ireq)) == -1)
3377 		return got_error_from_errno("imsg_compose "
3378 		    "COMMIT_PAINTING_REQUEST");
3379 
3380 	return flush_imsg(ibuf);
3381 }
3382 
3383 static const struct got_error *
3384 send_painted_commits(struct got_object_id_queue *ids, int *nids,
3385     size_t remain, int present_in_pack, struct imsgbuf *ibuf)
3386 {
3387 	const struct got_error *err = NULL;
3388 	struct ibuf *wbuf = NULL;
3389 	struct got_object_qid *qid;
3390 	size_t msglen;
3391 	int ncommits;
3392 	intptr_t color;
3393 
3394 	msglen = MIN(remain, MAX_IMSGSIZE - IMSG_HEADER_SIZE);
3395 	ncommits = (msglen - sizeof(struct got_imsg_painted_commits)) /
3396 	    sizeof(struct got_imsg_painted_commit);
3397 
3398 	wbuf = imsg_create(ibuf, GOT_IMSG_PAINTED_COMMITS, 0, 0, msglen);
3399 	if (wbuf == NULL) {
3400 		err = got_error_from_errno("imsg_create PAINTED_COMMITS");
3401 		return err;
3402 	}
3403 
3404 	/* Keep in sync with struct got_imsg_painted_commits! */
3405 	if (imsg_add(wbuf, &ncommits, sizeof(ncommits)) == -1)
3406 		return got_error_from_errno("imsg_add PAINTED_COMMITS");
3407 	if (imsg_add(wbuf, &present_in_pack, sizeof(present_in_pack)) == -1)
3408 		return got_error_from_errno("imsg_add PAINTED_COMMITS");
3409 
3410 	while (ncommits > 0) {
3411 		qid = STAILQ_FIRST(ids);
3412 		STAILQ_REMOVE_HEAD(ids, entry);
3413 		ncommits--;
3414 		(*nids)--;
3415 		color = (intptr_t)qid->data;
3416 
3417 		/* Keep in sync with struct got_imsg_painted_commit! */
3418 		if (imsg_add(wbuf, qid->id.sha1, SHA1_DIGEST_LENGTH) == -1)
3419 			return got_error_from_errno("imsg_add PAINTED_COMMITS");
3420 		if (imsg_add(wbuf, &color, sizeof(color)) == -1)
3421 			return got_error_from_errno("imsg_add PAINTED_COMMITS");
3422 
3423 		got_object_qid_free(qid);
3424 	}
3425 
3426 	wbuf->fd = -1;
3427 	imsg_close(ibuf, wbuf);
3428 
3429 	return flush_imsg(ibuf);
3430 }
3431 
3432 const struct got_error *
3433 got_privsep_send_painted_commits(struct imsgbuf *ibuf,
3434     struct got_object_id_queue *ids, int *nids,
3435     int present_in_pack, int flush)
3436 {
3437 	const struct got_error *err;
3438 	size_t remain;
3439 
3440 	if (*nids <= 0)
3441 		return NULL;
3442 
3443 	do {
3444 		remain = (sizeof(struct got_imsg_painted_commits)) +
3445 		    *nids * sizeof(struct got_imsg_painted_commit);
3446 		if (flush || remain >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
3447 			err = send_painted_commits(ids, nids, remain,
3448 			    present_in_pack, ibuf);
3449 			if (err)
3450 				return err;
3451 		}
3452 	} while (flush && *nids > 0);
3453 
3454 	return NULL;
3455 }
3456 
3457 const struct got_error *
3458 got_privsep_send_painting_commits_done(struct imsgbuf *ibuf)
3459 {
3460 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_PAINTING_DONE,
3461 	    0, 0, -1, NULL, 0)
3462 	    == -1)
3463 		return got_error_from_errno("imsg_compose "
3464 		    "COMMIT_PAINTING_DONE");
3465 
3466 	return flush_imsg(ibuf);
3467 }
3468 
3469 const struct got_error *
3470 got_privsep_recv_painted_commits(struct got_object_id_queue *new_ids,
3471     got_privsep_recv_painted_commit_cb cb, void *cb_arg, struct imsgbuf *ibuf)
3472 {
3473 	const struct got_error *err = NULL;
3474 	struct imsg imsg;
3475 	struct got_imsg_painted_commits icommits;
3476 	struct got_imsg_painted_commit icommit;
3477 	size_t datalen;
3478 	int i;
3479 
3480 	for (;;) {
3481 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3482 		if (err)
3483 			return err;
3484 
3485 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3486 		if (imsg.hdr.type == GOT_IMSG_COMMIT_PAINTING_DONE)
3487 			break;
3488 		if (imsg.hdr.type != GOT_IMSG_PAINTED_COMMITS)
3489 			return got_error(GOT_ERR_PRIVSEP_MSG);
3490 
3491 		if (datalen < sizeof(icommits))
3492 			return got_error(GOT_ERR_PRIVSEP_LEN);
3493 		memcpy(&icommits, imsg.data, sizeof(icommits));
3494 		if (icommits.ncommits * sizeof(icommit) < icommits.ncommits ||
3495 		    datalen < sizeof(icommits) +
3496 		    icommits.ncommits * sizeof(icommit))
3497 			return got_error(GOT_ERR_PRIVSEP_LEN);
3498 
3499 		for (i = 0; i < icommits.ncommits; i++) {
3500 			memcpy(&icommit,
3501 			    (uint8_t *)imsg.data + sizeof(icommits) + i * sizeof(icommit),
3502 			    sizeof(icommit));
3503 
3504 			if (icommits.present_in_pack) {
3505 				struct got_object_id id;
3506 				memcpy(id.sha1, icommit.id, SHA1_DIGEST_LENGTH);
3507 				err = cb(cb_arg, &id, icommit.color);
3508 				if (err)
3509 					break;
3510 			} else {
3511 				struct got_object_qid *qid;
3512 				err = got_object_qid_alloc_partial(&qid);
3513 				if (err)
3514 					break;
3515 				memcpy(qid->id.sha1, icommit.id,
3516 				    SHA1_DIGEST_LENGTH);
3517 				qid->data = (void *)icommit.color;
3518 				STAILQ_INSERT_TAIL(new_ids, qid, entry);
3519 			}
3520 		}
3521 
3522 		imsg_free(&imsg);
3523 	}
3524 
3525 	return err;
3526 }
3527 
3528 const struct got_error *
3529 got_privsep_unveil_exec_helpers(void)
3530 {
3531 	const char *helpers[] = {
3532 	    GOT_PATH_PROG_READ_PACK,
3533 	    GOT_PATH_PROG_READ_OBJECT,
3534 	    GOT_PATH_PROG_READ_COMMIT,
3535 	    GOT_PATH_PROG_READ_TREE,
3536 	    GOT_PATH_PROG_READ_BLOB,
3537 	    GOT_PATH_PROG_READ_TAG,
3538 	    GOT_PATH_PROG_READ_GITCONFIG,
3539 	    GOT_PATH_PROG_READ_GOTCONFIG,
3540 	    GOT_PATH_PROG_READ_PATCH,
3541 	    GOT_PATH_PROG_FETCH_PACK,
3542 	    GOT_PATH_PROG_INDEX_PACK,
3543 	    GOT_PATH_PROG_SEND_PACK,
3544 	};
3545 	size_t i;
3546 
3547 	for (i = 0; i < nitems(helpers); i++) {
3548 		if (unveil(helpers[i], "x") == 0)
3549 			continue;
3550 		return got_error_from_errno2("unveil", helpers[i]);
3551 	}
3552 
3553 	return NULL;
3554 }
3555 
3556 void
3557 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
3558 {
3559 	if (close(imsg_fds[0]) == -1) {
3560 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3561 		_exit(1);
3562 	}
3563 
3564 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
3565 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3566 		_exit(1);
3567 	}
3568 
3569 	closefrom(GOT_IMSG_FD_CHILD + 1);
3570 
3571 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
3572 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
3573 		    strerror(errno));
3574 		_exit(1);
3575 	}
3576 }