1 /*
2  * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
3  * Copyright (c) 2020 Ori Bernstein <ori@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/types.h>
19 #include <sys/queue.h>
20 #include <sys/uio.h>
21 #include <sys/wait.h>
22 
23 #include <ctype.h>
24 #include <limits.h>
25 #include <signal.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <errno.h>
30 #include <stdint.h>
31 #include <poll.h>
32 #include <imsg.h>
33 #include <sha1.h>
34 #include <unistd.h>
35 #include <zlib.h>
36 #include <time.h>
37 
38 #include "got_object.h"
39 #include "got_error.h"
40 #include "got_path.h"
41 #include "got_repository.h"
42 
43 #include "got_lib_sha1.h"
44 #include "got_lib_delta.h"
45 #include "got_lib_inflate.h"
46 #include "got_lib_object.h"
47 #include "got_lib_object_parse.h"
48 #include "got_lib_privsep.h"
49 #include "got_lib_pack.h"
50 
51 #ifndef MIN
52 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
53 #endif
54 
55 #ifndef nitems
56 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
57 #endif
58 
59 static const struct got_error *
60 poll_fd(int fd, int events, int timeout)
61 {
62 	struct pollfd pfd[1];
63 	struct timespec ts;
64 	sigset_t sigset;
65 	int n;
66 
67 	pfd[0].fd = fd;
68 	pfd[0].events = events;
69 
70 	ts.tv_sec = timeout;
71 	ts.tv_nsec = 0;
72 
73 	if (sigemptyset(&sigset) == -1)
74 		return got_error_from_errno("sigemptyset");
75 	if (sigaddset(&sigset, SIGWINCH) == -1)
76 		return got_error_from_errno("sigaddset");
77 
78 	n = ppoll(pfd, 1, timeout == INFTIM ? NULL : &ts, &sigset);
79 	if (n == -1)
80 		return got_error_from_errno("ppoll");
81 	if (n == 0)
82 		return got_error(GOT_ERR_TIMEOUT);
83 	if (pfd[0].revents & (POLLERR | POLLNVAL))
84 		return got_error_from_errno("poll error");
85 	if (pfd[0].revents & (events | POLLHUP))
86 		return NULL;
87 
88 	return got_error(GOT_ERR_INTERRUPT);
89 }
90 
91 static const struct got_error *
92 read_imsg(struct imsgbuf *ibuf)
93 {
94 	const struct got_error *err;
95 	size_t n;
96 
97 	err = poll_fd(ibuf->fd, POLLIN, INFTIM);
98 	if (err)
99 		return err;
100 
101 	n = imsg_read(ibuf);
102 	if (n == -1) {
103 		if (errno == EAGAIN) /* Could be a file-descriptor leak. */
104 			return got_error(GOT_ERR_PRIVSEP_NO_FD);
105 		return got_error(GOT_ERR_PRIVSEP_READ);
106 	}
107 	if (n == 0)
108 		return got_error(GOT_ERR_PRIVSEP_PIPE);
109 
110 	return NULL;
111 }
112 
113 const struct got_error *
114 got_privsep_wait_for_child(pid_t pid)
115 {
116 	int child_status;
117 
118 	if (waitpid(pid, &child_status, 0) == -1)
119 		return got_error_from_errno("waitpid");
120 
121 	if (!WIFEXITED(child_status))
122 		return got_error(GOT_ERR_PRIVSEP_DIED);
123 
124 	if (WEXITSTATUS(child_status) != 0)
125 		return got_error(GOT_ERR_PRIVSEP_EXIT);
126 
127 	return NULL;
128 }
129 
130 static const struct got_error *
131 recv_imsg_error(struct imsg *imsg, size_t datalen)
132 {
133 	struct got_imsg_error *ierr;
134 
135 	if (datalen != sizeof(*ierr))
136 		return got_error(GOT_ERR_PRIVSEP_LEN);
137 
138 	ierr = imsg->data;
139 	if (ierr->code == GOT_ERR_ERRNO) {
140 		static struct got_error serr;
141 		serr.code = GOT_ERR_ERRNO;
142 		serr.msg = strerror(ierr->errno_code);
143 		return &serr;
144 	}
145 
146 	return got_error(ierr->code);
147 }
148 
149 const struct got_error *
150 got_privsep_recv_imsg(struct imsg *imsg, struct imsgbuf *ibuf,
151     size_t min_datalen)
152 {
153 	const struct got_error *err;
154 	ssize_t n;
155 
156 	n = imsg_get(ibuf, imsg);
157 	if (n == -1)
158 		return got_error_from_errno("imsg_get");
159 
160 	while (n == 0) {
161 		err = read_imsg(ibuf);
162 		if (err)
163 			return err;
164 		n = imsg_get(ibuf, imsg);
165 		if (n == -1)
166 			return got_error_from_errno("imsg_get");
167 	}
168 
169 	if (imsg->hdr.len < IMSG_HEADER_SIZE + min_datalen)
170 		return got_error(GOT_ERR_PRIVSEP_LEN);
171 
172 	if (imsg->hdr.type == GOT_IMSG_ERROR) {
173 		size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
174 		return recv_imsg_error(imsg, datalen);
175 	}
176 
177 	return NULL;
178 }
179 
180 /* Attempt to send an error in an imsg. Complain on stderr as a last resort. */
181 void
182 got_privsep_send_error(struct imsgbuf *ibuf, const struct got_error *err)
183 {
184 	const struct got_error *poll_err;
185 	struct got_imsg_error ierr;
186 	int ret;
187 
188 	ierr.code = err->code;
189 	if (err->code == GOT_ERR_ERRNO)
190 		ierr.errno_code = errno;
191 	else
192 		ierr.errno_code = 0;
193 	ret = imsg_compose(ibuf, GOT_IMSG_ERROR, 0, 0, -1, &ierr, sizeof(ierr));
194 	if (ret == -1) {
195 		fprintf(stderr, "%s: error %d \"%s\": imsg_compose: %s\n",
196 		    getprogname(), err->code, err->msg, strerror(errno));
197 		return;
198 	}
199 
200 	poll_err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
201 	if (poll_err) {
202 		fprintf(stderr, "%s: error %d \"%s\": poll: %s\n",
203 		    getprogname(), err->code, err->msg, poll_err->msg);
204 		return;
205 	}
206 
207 	ret = imsg_flush(ibuf);
208 	if (ret == -1) {
209 		fprintf(stderr, "%s: error %d \"%s\": imsg_flush: %s\n",
210 		    getprogname(), err->code, err->msg, strerror(errno));
211 		imsg_clear(ibuf);
212 		return;
213 	}
214 }
215 
216 static const struct got_error *
217 flush_imsg(struct imsgbuf *ibuf)
218 {
219 	const struct got_error *err;
220 
221 	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
222 	if (err)
223 		return err;
224 
225 	if (imsg_flush(ibuf) == -1) {
226 		imsg_clear(ibuf);
227 		return got_error_from_errno("imsg_flush");
228 	}
229 
230 	return NULL;
231 }
232 
233 const struct got_error *
234 got_privsep_flush_imsg(struct imsgbuf *ibuf)
235 {
236 	return flush_imsg(ibuf);
237 }
238 
239 const struct got_error *
240 got_privsep_send_stop(int fd)
241 {
242 	const struct got_error *err = NULL;
243 	struct imsgbuf ibuf;
244 
245 	imsg_init(&ibuf, fd);
246 
247 	if (imsg_compose(&ibuf, GOT_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
248 		return got_error_from_errno("imsg_compose STOP");
249 
250 	err = flush_imsg(&ibuf);
251 	return err;
252 }
253 
254 const struct got_error *
255 got_privsep_send_obj_req(struct imsgbuf *ibuf, int fd,
256     struct got_object_id *id)
257 {
258 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_REQUEST, 0, 0, fd,
259 	    id, sizeof(*id)) == -1)
260 		return got_error_from_errno("imsg_compose OBJECT_REQUEST");
261 
262 	return flush_imsg(ibuf);
263 }
264 
265 const struct got_error *
266 got_privsep_send_raw_obj_req(struct imsgbuf *ibuf, int fd,
267     struct got_object_id *id)
268 {
269 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_REQUEST, 0, 0, fd,
270 	    id, sizeof(*id)) == -1)
271 		return got_error_from_errno("imsg_compose RAW_OBJECT_REQUEST");
272 
273 	return flush_imsg(ibuf);
274 }
275 
276 const struct got_error *
277 got_privsep_send_raw_obj_outfd(struct imsgbuf *ibuf, int outfd)
278 {
279 	const struct got_error *err = NULL;
280 
281 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_OUTFD, 0, 0, outfd, NULL, 0)
282 	    == -1) {
283 		err = got_error_from_errno("imsg_compose RAW_OBJECT_OUTFD");
284 		close(outfd);
285 		return err;
286 	}
287 
288 	return flush_imsg(ibuf);
289 }
290 
291 const struct got_error *
292 got_privsep_send_raw_obj(struct imsgbuf *ibuf, off_t size, size_t hdrlen,
293     uint8_t *data)
294 {
295 	const struct got_error *err = NULL;
296 	struct got_imsg_raw_obj iobj;
297 	size_t len = sizeof(iobj);
298 	struct ibuf *wbuf;
299 
300 	iobj.hdrlen = hdrlen;
301 	iobj.size = size;
302 
303 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX)
304 		len += (size_t)size + hdrlen;
305 
306 	wbuf = imsg_create(ibuf, GOT_IMSG_RAW_OBJECT, 0, 0, len);
307 	if (wbuf == NULL) {
308 		err = got_error_from_errno("imsg_create RAW_OBJECT");
309 		return err;
310 	}
311 
312 	if (imsg_add(wbuf, &iobj, sizeof(iobj)) == -1)
313 		return got_error_from_errno("imsg_add RAW_OBJECT");
314 
315 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
316 		if (imsg_add(wbuf, data, size + hdrlen) == -1)
317 			return got_error_from_errno("imsg_add RAW_OBJECT");
318 	}
319 
320 	wbuf->fd = -1;
321 	imsg_close(ibuf, wbuf);
322 
323 	return flush_imsg(ibuf);
324 }
325 
326 const struct got_error *
327 got_privsep_recv_raw_obj(uint8_t **outbuf, off_t *size, size_t *hdrlen,
328     struct imsgbuf *ibuf)
329 {
330 	const struct got_error *err = NULL;
331 	struct imsg imsg;
332 	struct got_imsg_raw_obj *iobj;
333 	size_t datalen;
334 
335 	*outbuf = NULL;
336 
337 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
338 	if (err)
339 		return err;
340 
341 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
342 
343 	switch (imsg.hdr.type) {
344 	case GOT_IMSG_RAW_OBJECT:
345 		if (datalen < sizeof(*iobj)) {
346 			err = got_error(GOT_ERR_PRIVSEP_LEN);
347 			break;
348 		}
349 		iobj = imsg.data;
350 		*size = iobj->size;
351 		*hdrlen = iobj->hdrlen;
352 
353 		if (datalen == sizeof(*iobj)) {
354 			/* Data has been written to file descriptor. */
355 			break;
356 		}
357 
358 		if (*size + *hdrlen > GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
359 			err = got_error(GOT_ERR_PRIVSEP_LEN);
360 			break;
361 		}
362 
363 		*outbuf = malloc(*size + *hdrlen);
364 		if (*outbuf == NULL) {
365 			err = got_error_from_errno("malloc");
366 			break;
367 		}
368 		memcpy(*outbuf, imsg.data + sizeof(*iobj), *size + *hdrlen);
369 		break;
370 	default:
371 		err = got_error(GOT_ERR_PRIVSEP_MSG);
372 		break;
373 	}
374 
375 	imsg_free(&imsg);
376 
377 	return err;
378 }
379 
380 const struct got_error *
381 got_privsep_send_commit_req(struct imsgbuf *ibuf, int fd,
382     struct got_object_id *id, int pack_idx)
383 {
384 	const struct got_error *err = NULL;
385 	struct got_imsg_packed_object iobj;
386 	void *data;
387 	size_t len;
388 
389 	if (pack_idx != -1) { /* commit is packed */
390 		iobj.idx = pack_idx;
391 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
392 		data = &iobj;
393 		len = sizeof(iobj);
394 	} else {
395 		data = id;
396 		len = sizeof(*id);
397 	}
398 
399 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_REQUEST, 0, 0, fd, data, len)
400 	    == -1) {
401 		err = got_error_from_errno("imsg_compose COMMIT_REQUEST");
402 		close(fd);
403 		return err;
404 	}
405 
406 	return flush_imsg(ibuf);
407 }
408 
409 const struct got_error *
410 got_privsep_send_tree_req(struct imsgbuf *ibuf, int fd,
411     struct got_object_id *id, int pack_idx)
412 {
413 	struct ibuf *wbuf;
414 	size_t len;
415 
416 	if (pack_idx != -1)
417 		len = sizeof(struct got_imsg_packed_object);
418 	else
419 		len = sizeof(*id);
420 
421 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_REQUEST, 0, 0, len);
422 	if (wbuf == NULL)
423 		return got_error_from_errno("imsg_create TREE_REQUEST");
424 
425 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1)
426 		return got_error_from_errno("imsg_add TREE_REQUEST");
427 
428 	if (pack_idx != -1) { /* tree is packed */
429 		if (imsg_add(wbuf, &pack_idx, sizeof(pack_idx)) == -1)
430 			return got_error_from_errno("imsg_add TREE_REQUEST");
431 	}
432 
433 	wbuf->fd = fd;
434 	imsg_close(ibuf, wbuf);
435 
436 	return flush_imsg(ibuf);
437 }
438 
439 const struct got_error *
440 got_privsep_send_tag_req(struct imsgbuf *ibuf, int fd,
441     struct got_object_id *id, int pack_idx)
442 {
443 	struct got_imsg_packed_object iobj;
444 	void *data;
445 	size_t len;
446 
447 	if (pack_idx != -1) { /* tag is packed */
448 		iobj.idx = pack_idx;
449 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
450 		data = &iobj;
451 		len = sizeof(iobj);
452 	} else {
453 		data = id;
454 		len = sizeof(*id);
455 	}
456 
457 	if (imsg_compose(ibuf, GOT_IMSG_TAG_REQUEST, 0, 0, fd, data, len)
458 	    == -1)
459 		return got_error_from_errno("imsg_compose TAG_REQUEST");
460 
461 	return flush_imsg(ibuf);
462 }
463 
464 const struct got_error *
465 got_privsep_send_blob_req(struct imsgbuf *ibuf, int infd,
466     struct got_object_id *id, int pack_idx)
467 {
468 	const struct got_error *err = NULL;
469 	struct got_imsg_packed_object iobj;
470 	void *data;
471 	size_t len;
472 
473 	if (pack_idx != -1) { /* blob is packed */
474 		iobj.idx = pack_idx;
475 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
476 		data = &iobj;
477 		len = sizeof(iobj);
478 	} else {
479 		data = id;
480 		len = sizeof(*id);
481 	}
482 
483 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_REQUEST, 0, 0, infd, data, len)
484 	    == -1) {
485 		err = got_error_from_errno("imsg_compose BLOB_REQUEST");
486 		close(infd);
487 		return err;
488 	}
489 
490 	return flush_imsg(ibuf);
491 }
492 
493 const struct got_error *
494 got_privsep_send_blob_outfd(struct imsgbuf *ibuf, int outfd)
495 {
496 	const struct got_error *err = NULL;
497 
498 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_OUTFD, 0, 0, outfd, NULL, 0)
499 	    == -1) {
500 		err = got_error_from_errno("imsg_compose BLOB_OUTFD");
501 		close(outfd);
502 		return err;
503 	}
504 
505 	return flush_imsg(ibuf);
506 }
507 
508 static const struct got_error *
509 send_fd(struct imsgbuf *ibuf, int imsg_code, int fd)
510 {
511 	const struct got_error *err = NULL;
512 
513 	if (imsg_compose(ibuf, imsg_code, 0, 0, fd, NULL, 0) == -1) {
514 		err = got_error_from_errno("imsg_compose TMPFD");
515 		close(fd);
516 		return err;
517 	}
518 
519 	return flush_imsg(ibuf);
520 }
521 
522 const struct got_error *
523 got_privsep_send_tmpfd(struct imsgbuf *ibuf, int fd)
524 {
525 	return send_fd(ibuf, GOT_IMSG_TMPFD, fd);
526 }
527 
528 const struct got_error *
529 got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj)
530 {
531 	struct got_imsg_object iobj;
532 
533 	memcpy(iobj.id, obj->id.sha1, sizeof(iobj.id));
534 	iobj.type = obj->type;
535 	iobj.flags = obj->flags;
536 	iobj.hdrlen = obj->hdrlen;
537 	iobj.size = obj->size;
538 	if (iobj.flags & GOT_OBJ_FLAG_PACKED) {
539 		iobj.pack_offset = obj->pack_offset;
540 		iobj.pack_idx = obj->pack_idx;
541 	}
542 
543 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
544 	    == -1)
545 		return got_error_from_errno("imsg_compose OBJECT");
546 
547 	return flush_imsg(ibuf);
548 }
549 
550 const struct got_error *
551 got_privsep_send_fetch_req(struct imsgbuf *ibuf, int fd,
552     struct got_pathlist_head *have_refs, int fetch_all_branches,
553     struct got_pathlist_head *wanted_branches,
554     struct got_pathlist_head *wanted_refs, int list_refs_only, int verbosity)
555 {
556 	const struct got_error *err = NULL;
557 	struct ibuf *wbuf;
558 	size_t len;
559 	struct got_pathlist_entry *pe;
560 	struct got_imsg_fetch_request fetchreq;
561 
562 	memset(&fetchreq, 0, sizeof(fetchreq));
563 	fetchreq.fetch_all_branches = fetch_all_branches;
564 	fetchreq.list_refs_only = list_refs_only;
565 	fetchreq.verbosity = verbosity;
566 	TAILQ_FOREACH(pe, have_refs, entry)
567 		fetchreq.n_have_refs++;
568 	TAILQ_FOREACH(pe, wanted_branches, entry)
569 		fetchreq.n_wanted_branches++;
570 	TAILQ_FOREACH(pe, wanted_refs, entry)
571 		fetchreq.n_wanted_refs++;
572 	len = sizeof(struct got_imsg_fetch_request);
573 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
574 		close(fd);
575 		return got_error(GOT_ERR_NO_SPACE);
576 	}
577 
578 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_REQUEST, 0, 0, fd,
579 	    &fetchreq, sizeof(fetchreq)) == -1)
580 		return got_error_from_errno(
581 		    "imsg_compose FETCH_SERVER_PROGRESS");
582 
583 	err = flush_imsg(ibuf);
584 	if (err) {
585 		close(fd);
586 		return err;
587 	}
588 	fd = -1;
589 
590 	TAILQ_FOREACH(pe, have_refs, entry) {
591 		const char *name = pe->path;
592 		size_t name_len = pe->path_len;
593 		struct got_object_id *id = pe->data;
594 
595 		len = sizeof(struct got_imsg_fetch_have_ref) + name_len;
596 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_HAVE_REF, 0, 0, len);
597 		if (wbuf == NULL)
598 			return got_error_from_errno("imsg_create FETCH_HAVE_REF");
599 
600 		/* Keep in sync with struct got_imsg_fetch_have_ref! */
601 		if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1)
602 			return got_error_from_errno("imsg_add FETCH_HAVE_REF");
603 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
604 			return got_error_from_errno("imsg_add FETCH_HAVE_REF");
605 		if (imsg_add(wbuf, name, name_len) == -1)
606 			return got_error_from_errno("imsg_add FETCH_HAVE_REF");
607 
608 		wbuf->fd = -1;
609 		imsg_close(ibuf, wbuf);
610 		err = flush_imsg(ibuf);
611 		if (err)
612 			return err;
613 	}
614 
615 	TAILQ_FOREACH(pe, wanted_branches, entry) {
616 		const char *name = pe->path;
617 		size_t name_len = pe->path_len;
618 
619 		len = sizeof(struct got_imsg_fetch_wanted_branch) + name_len;
620 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_BRANCH, 0, 0,
621 		    len);
622 		if (wbuf == NULL)
623 			return got_error_from_errno(
624 			    "imsg_create FETCH_WANTED_BRANCH");
625 
626 		/* Keep in sync with struct got_imsg_fetch_wanted_branch! */
627 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
628 			return got_error_from_errno(
629 			    "imsg_add FETCH_WANTED_BRANCH");
630 		if (imsg_add(wbuf, name, name_len) == -1)
631 			return got_error_from_errno(
632 			    "imsg_add FETCH_WANTED_BRANCH");
633 
634 		wbuf->fd = -1;
635 		imsg_close(ibuf, wbuf);
636 		err = flush_imsg(ibuf);
637 		if (err)
638 			return err;
639 	}
640 
641 	TAILQ_FOREACH(pe, wanted_refs, entry) {
642 		const char *name = pe->path;
643 		size_t name_len = pe->path_len;
644 
645 		len = sizeof(struct got_imsg_fetch_wanted_ref) + name_len;
646 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_REF, 0, 0,
647 		    len);
648 		if (wbuf == NULL)
649 			return got_error_from_errno(
650 			    "imsg_create FETCH_WANTED_REF");
651 
652 		/* Keep in sync with struct got_imsg_fetch_wanted_ref! */
653 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
654 			return got_error_from_errno(
655 			    "imsg_add FETCH_WANTED_REF");
656 		if (imsg_add(wbuf, name, name_len) == -1)
657 			return got_error_from_errno(
658 			    "imsg_add FETCH_WANTED_REF");
659 
660 		wbuf->fd = -1;
661 		imsg_close(ibuf, wbuf);
662 		err = flush_imsg(ibuf);
663 		if (err)
664 			return err;
665 	}
666 
667 
668 	return NULL;
669 
670 }
671 
672 const struct got_error *
673 got_privsep_send_fetch_outfd(struct imsgbuf *ibuf, int fd)
674 {
675 	return send_fd(ibuf, GOT_IMSG_FETCH_OUTFD, fd);
676 }
677 
678 const struct got_error *
679 got_privsep_recv_fetch_progress(int *done, struct got_object_id **id,
680     char **refname, struct got_pathlist_head *symrefs, char **server_progress,
681     off_t *packfile_size, uint8_t *pack_sha1, struct imsgbuf *ibuf)
682 {
683 	const struct got_error *err = NULL;
684 	struct imsg imsg;
685 	size_t datalen;
686 	struct got_imsg_fetch_symrefs *isymrefs = NULL;
687 	size_t n, remain;
688 	off_t off;
689 	int i;
690 
691 	*done = 0;
692 	*id = NULL;
693 	*refname = NULL;
694 	*server_progress = NULL;
695 	*packfile_size = 0;
696 	memset(pack_sha1, 0, SHA1_DIGEST_LENGTH);
697 
698 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
699 	if (err)
700 		return err;
701 
702 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
703 	switch (imsg.hdr.type) {
704 	case GOT_IMSG_ERROR:
705 		if (datalen < sizeof(struct got_imsg_error)) {
706 			err = got_error(GOT_ERR_PRIVSEP_LEN);
707 			break;
708 		}
709 		err = recv_imsg_error(&imsg, datalen);
710 		break;
711 	case GOT_IMSG_FETCH_SYMREFS:
712 		if (datalen < sizeof(*isymrefs)) {
713 			err = got_error(GOT_ERR_PRIVSEP_LEN);
714 			break;
715 		}
716 		if (isymrefs != NULL) {
717 			err = got_error(GOT_ERR_PRIVSEP_MSG);
718 			break;
719 		}
720 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
721 		off = sizeof(*isymrefs);
722 		remain = datalen - off;
723 		for (n = 0; n < isymrefs->nsymrefs; n++) {
724 			struct got_imsg_fetch_symref *s;
725 			char *name, *target;
726 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
727 				err = got_error(GOT_ERR_PRIVSEP_LEN);
728 				goto done;
729 			}
730 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
731 			off += sizeof(*s);
732 			remain -= sizeof(*s);
733 			if (remain < s->name_len) {
734 				err = got_error(GOT_ERR_PRIVSEP_LEN);
735 				goto done;
736 			}
737 			name = strndup(imsg.data + off, s->name_len);
738 			if (name == NULL) {
739 				err = got_error_from_errno("strndup");
740 				goto done;
741 			}
742 			off += s->name_len;
743 			remain -= s->name_len;
744 			if (remain < s->target_len) {
745 				err = got_error(GOT_ERR_PRIVSEP_LEN);
746 				free(name);
747 				goto done;
748 			}
749 			target = strndup(imsg.data + off, s->target_len);
750 			if (target == NULL) {
751 				err = got_error_from_errno("strndup");
752 				free(name);
753 				goto done;
754 			}
755 			off += s->target_len;
756 			remain -= s->target_len;
757 			err = got_pathlist_append(symrefs, name, target);
758 			if (err) {
759 				free(name);
760 				free(target);
761 				goto done;
762 			}
763 		}
764 		break;
765 	case GOT_IMSG_FETCH_REF:
766 		if (datalen <= SHA1_DIGEST_LENGTH) {
767 			err = got_error(GOT_ERR_PRIVSEP_MSG);
768 			break;
769 		}
770 		*id = malloc(sizeof(**id));
771 		if (*id == NULL) {
772 			err = got_error_from_errno("malloc");
773 			break;
774 		}
775 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
776 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
777 		    datalen - SHA1_DIGEST_LENGTH);
778 		if (*refname == NULL) {
779 			err = got_error_from_errno("strndup");
780 			break;
781 		}
782 		break;
783 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
784 		if (datalen == 0) {
785 			err = got_error(GOT_ERR_PRIVSEP_LEN);
786 			break;
787 		}
788 		*server_progress = strndup(imsg.data, datalen);
789 		if (*server_progress == NULL) {
790 			err = got_error_from_errno("strndup");
791 			break;
792 		}
793 		for (i = 0; i < datalen; i++) {
794 			if (!isprint((unsigned char)(*server_progress)[i]) &&
795 			    !isspace((unsigned char)(*server_progress)[i])) {
796 				err = got_error(GOT_ERR_PRIVSEP_MSG);
797 				free(*server_progress);
798 				*server_progress = NULL;
799 				goto done;
800 			}
801 		}
802 		break;
803 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
804 		if (datalen < sizeof(*packfile_size)) {
805 			err = got_error(GOT_ERR_PRIVSEP_MSG);
806 			break;
807 		}
808 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
809 		break;
810 	case GOT_IMSG_FETCH_DONE:
811 		if (datalen != SHA1_DIGEST_LENGTH) {
812 			err = got_error(GOT_ERR_PRIVSEP_MSG);
813 			break;
814 		}
815 		memcpy(pack_sha1, imsg.data, SHA1_DIGEST_LENGTH);
816 		*done = 1;
817 		break;
818 	default:
819 		err = got_error(GOT_ERR_PRIVSEP_MSG);
820 		break;
821 	}
822 done:
823 	if (err) {
824 		free(*id);
825 		*id = NULL;
826 		free(*refname);
827 		*refname = NULL;
828 	}
829 	imsg_free(&imsg);
830 	return err;
831 }
832 
833 static const struct got_error *
834 send_send_ref(const char *name, size_t name_len, struct got_object_id *id,
835     int delete, struct imsgbuf *ibuf)
836 {
837 	size_t len;
838 	struct ibuf *wbuf;
839 
840 	len = sizeof(struct got_imsg_send_ref) + name_len;
841 	wbuf = imsg_create(ibuf, GOT_IMSG_SEND_REF, 0, 0, len);
842 	if (wbuf == NULL)
843 		return got_error_from_errno("imsg_create SEND_REF");
844 
845 	/* Keep in sync with struct got_imsg_send_ref! */
846 	if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1)
847 		return got_error_from_errno("imsg_add SEND_REF");
848 	if (imsg_add(wbuf, &delete, sizeof(delete)) == -1)
849 		return got_error_from_errno("imsg_add SEND_REF");
850 	if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
851 		return got_error_from_errno("imsg_add SEND_REF");
852 	if (imsg_add(wbuf, name, name_len) == -1)
853 		return got_error_from_errno("imsg_add SEND_REF");
854 
855 	wbuf->fd = -1;
856 	imsg_close(ibuf, wbuf);
857 	return flush_imsg(ibuf);
858 }
859 
860 const struct got_error *
861 got_privsep_send_send_req(struct imsgbuf *ibuf, int fd,
862     struct got_pathlist_head *have_refs,
863     struct got_pathlist_head *delete_refs,
864     int verbosity)
865 {
866 	const struct got_error *err = NULL;
867 	struct got_pathlist_entry *pe;
868 	struct got_imsg_send_request sendreq;
869 	struct got_object_id zero_id;
870 
871 	memset(&zero_id, 0, sizeof(zero_id));
872 	memset(&sendreq, 0, sizeof(sendreq));
873 	sendreq.verbosity = verbosity;
874 	TAILQ_FOREACH(pe, have_refs, entry)
875 		sendreq.nrefs++;
876 	TAILQ_FOREACH(pe, delete_refs, entry)
877 		sendreq.nrefs++;
878 	if (imsg_compose(ibuf, GOT_IMSG_SEND_REQUEST, 0, 0, fd,
879 	    &sendreq, sizeof(sendreq)) == -1) {
880 		err = got_error_from_errno(
881 		    "imsg_compose FETCH_SERVER_PROGRESS");
882 		goto done;
883 	}
884 
885 	err = flush_imsg(ibuf);
886 	if (err)
887 		goto done;
888 	fd = -1;
889 
890 	TAILQ_FOREACH(pe, have_refs, entry) {
891 		const char *name = pe->path;
892 		size_t name_len = pe->path_len;
893 		struct got_object_id *id = pe->data;
894 		err = send_send_ref(name, name_len, id, 0, ibuf);
895 		if (err)
896 			goto done;
897 	}
898 
899 	TAILQ_FOREACH(pe, delete_refs, entry) {
900 		const char *name = pe->path;
901 		size_t name_len = pe->path_len;
902 		err = send_send_ref(name, name_len, &zero_id, 1, ibuf);
903 		if (err)
904 			goto done;
905 	}
906 done:
907 	if (fd != -1 && close(fd) == -1 && err == NULL)
908 		err = got_error_from_errno("close");
909 	return err;
910 
911 }
912 
913 const struct got_error *
914 got_privsep_recv_send_remote_refs(struct got_pathlist_head *remote_refs,
915     struct imsgbuf *ibuf)
916 {
917 	const struct got_error *err = NULL;
918 	struct imsg imsg;
919 	size_t datalen;
920 	int done = 0;
921 	struct got_imsg_send_remote_ref iremote_ref;
922 	struct got_object_id *id = NULL;
923 	char *refname = NULL;
924 	struct got_pathlist_entry *new;
925 
926 	while (!done) {
927 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
928 		if (err)
929 			return err;
930 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
931 		switch (imsg.hdr.type) {
932 		case GOT_IMSG_ERROR:
933 			if (datalen < sizeof(struct got_imsg_error)) {
934 				err = got_error(GOT_ERR_PRIVSEP_LEN);
935 				goto done;
936 			}
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 		if (datalen < sizeof(struct got_imsg_error)) {
1021 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1022 			break;
1023 		}
1024 		err = recv_imsg_error(&imsg, datalen);
1025 		break;
1026 	case GOT_IMSG_SEND_UPLOAD_PROGRESS:
1027 		if (datalen < sizeof(*bytes_sent)) {
1028 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1029 			break;
1030 		}
1031 		memcpy(bytes_sent, imsg.data, sizeof(*bytes_sent));
1032 		break;
1033 	case GOT_IMSG_SEND_REF_STATUS:
1034 		if (datalen < sizeof(iref_status)) {
1035 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1036 			break;
1037 		}
1038 		memcpy(&iref_status, imsg.data, sizeof(iref_status));
1039 		if (datalen != sizeof(iref_status) + iref_status.name_len) {
1040 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1041 			break;
1042 		}
1043 		*success = iref_status.success;
1044 		*refname = strndup(imsg.data + sizeof(iref_status),
1045 		    iref_status.name_len);
1046 		break;
1047 	case GOT_IMSG_SEND_DONE:
1048 		if (datalen != 0) {
1049 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1050 			break;
1051 		}
1052 		*done = 1;
1053 		break;
1054 	default:
1055 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1056 		break;
1057 	}
1058 
1059 	imsg_free(&imsg);
1060 	return err;
1061 }
1062 
1063 const struct got_error *
1064 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_sha1,
1065     int fd)
1066 {
1067 	const struct got_error *err = NULL;
1068 
1069 	/* Keep in sync with struct got_imsg_index_pack_request */
1070 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
1071 	    pack_sha1, SHA1_DIGEST_LENGTH) == -1) {
1072 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
1073 		close(fd);
1074 		return err;
1075 	}
1076 	return flush_imsg(ibuf);
1077 }
1078 
1079 const struct got_error *
1080 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
1081 {
1082 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
1083 }
1084 
1085 const struct got_error *
1086 got_privsep_recv_index_progress(int *done, int *nobj_total,
1087     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
1088     struct imsgbuf *ibuf)
1089 {
1090 	const struct got_error *err = NULL;
1091 	struct imsg imsg;
1092 	struct got_imsg_index_pack_progress *iprogress;
1093 	size_t datalen;
1094 
1095 	*done = 0;
1096 	*nobj_total = 0;
1097 	*nobj_indexed = 0;
1098 	*nobj_resolved = 0;
1099 
1100 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1101 	if (err)
1102 		return err;
1103 
1104 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1105 	switch (imsg.hdr.type) {
1106 	case GOT_IMSG_ERROR:
1107 		if (datalen < sizeof(struct got_imsg_error)) {
1108 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1109 			break;
1110 		}
1111 		err = recv_imsg_error(&imsg, datalen);
1112 		break;
1113 	case GOT_IMSG_IDXPACK_PROGRESS:
1114 		if (datalen < sizeof(*iprogress)) {
1115 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1116 			break;
1117 		}
1118 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
1119 		*nobj_total = iprogress->nobj_total;
1120 		*nobj_indexed = iprogress->nobj_indexed;
1121 		*nobj_loose = iprogress->nobj_loose;
1122 		*nobj_resolved = iprogress->nobj_resolved;
1123 		break;
1124 	case GOT_IMSG_IDXPACK_DONE:
1125 		if (datalen != 0) {
1126 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1127 			break;
1128 		}
1129 		*done = 1;
1130 		break;
1131 	default:
1132 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1133 		break;
1134 	}
1135 
1136 	imsg_free(&imsg);
1137 	return err;
1138 }
1139 
1140 const struct got_error *
1141 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
1142     struct imsgbuf *ibuf)
1143 {
1144 	struct got_imsg_object *iobj;
1145 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1146 
1147 	if (datalen != sizeof(*iobj))
1148 		return got_error(GOT_ERR_PRIVSEP_LEN);
1149 	iobj = imsg->data;
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 	if (icommit->author_len == 0) {
1321 		(*commit)->author = strdup("");
1322 		if ((*commit)->author == NULL) {
1323 			err = got_error_from_errno("strdup");
1324 			goto done;
1325 		}
1326 	} else {
1327 		(*commit)->author = malloc(icommit->author_len + 1);
1328 		if ((*commit)->author == NULL) {
1329 			err = got_error_from_errno("malloc");
1330 			goto done;
1331 		}
1332 		memcpy((*commit)->author, imsg->data + len,
1333 		    icommit->author_len);
1334 		(*commit)->author[icommit->author_len] = '\0';
1335 	}
1336 	len += icommit->author_len;
1337 
1338 	if (icommit->committer_len == 0) {
1339 		(*commit)->committer = strdup("");
1340 		if ((*commit)->committer == NULL) {
1341 			err = got_error_from_errno("strdup");
1342 			goto done;
1343 		}
1344 	} else {
1345 		(*commit)->committer =
1346 		    malloc(icommit->committer_len + 1);
1347 		if ((*commit)->committer == NULL) {
1348 			err = got_error_from_errno("malloc");
1349 			goto done;
1350 		}
1351 		memcpy((*commit)->committer, imsg->data + len,
1352 		    icommit->committer_len);
1353 		(*commit)->committer[icommit->committer_len] = '\0';
1354 	}
1355 	len += icommit->committer_len;
1356 
1357 	if (icommit->logmsg_len == 0) {
1358 		(*commit)->logmsg = strdup("");
1359 		if ((*commit)->logmsg == NULL) {
1360 			err = got_error_from_errno("strdup");
1361 			goto done;
1362 		}
1363 	} else {
1364 		size_t offset = 0, remain = icommit->logmsg_len;
1365 
1366 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1367 		if ((*commit)->logmsg == NULL) {
1368 			err = got_error_from_errno("malloc");
1369 			goto done;
1370 		}
1371 		while (remain > 0) {
1372 			struct imsg imsg_log;
1373 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1374 			    remain);
1375 
1376 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1377 			if (err)
1378 				goto done;
1379 
1380 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1381 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1382 				goto done;
1383 			}
1384 
1385 			memcpy((*commit)->logmsg + offset,
1386 			    imsg_log.data, n);
1387 			imsg_free(&imsg_log);
1388 			offset += n;
1389 			remain -= n;
1390 		}
1391 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1392 	}
1393 
1394 	for (i = 0; i < icommit->nparents; i++) {
1395 		struct got_object_qid *qid;
1396 
1397 		err = got_object_qid_alloc_partial(&qid);
1398 		if (err)
1399 			break;
1400 		memcpy(&qid->id, imsg->data + len +
1401 		    i * SHA1_DIGEST_LENGTH, sizeof(qid->id));
1402 		STAILQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1403 		(*commit)->nparents++;
1404 	}
1405 done:
1406 	if (err) {
1407 		got_object_commit_close(*commit);
1408 		*commit = NULL;
1409 	}
1410 	return err;
1411 }
1412 
1413 const struct got_error *
1414 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1415 {
1416 	const struct got_error *err = NULL;
1417 	struct imsg imsg;
1418 	size_t datalen;
1419 	const size_t min_datalen =
1420 	    MIN(sizeof(struct got_imsg_error),
1421 	    sizeof(struct got_imsg_commit_object));
1422 
1423 	*commit = NULL;
1424 
1425 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1426 	if (err)
1427 		return err;
1428 
1429 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1430 
1431 	switch (imsg.hdr.type) {
1432 	case GOT_IMSG_COMMIT:
1433 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1434 		break;
1435 	default:
1436 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1437 		break;
1438 	}
1439 
1440 	imsg_free(&imsg);
1441 
1442 	return err;
1443 }
1444 
1445 static const struct got_error *
1446 send_tree_entries_batch(struct imsgbuf *ibuf,
1447     struct got_parsed_tree_entry *entries, int idx0, int idxN, size_t len)
1448 {
1449 	struct ibuf *wbuf;
1450 	struct got_imsg_tree_entries ientries;
1451 	int i;
1452 
1453 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRIES, 0, 0, len);
1454 	if (wbuf == NULL)
1455 		return got_error_from_errno("imsg_create TREE_ENTRY");
1456 
1457 	ientries.nentries = idxN - idx0 + 1;
1458 	if (imsg_add(wbuf, &ientries, sizeof(ientries)) == -1)
1459 		return got_error_from_errno("imsg_add TREE_ENTRY");
1460 
1461 	for (i = idx0; i <= idxN; i++) {
1462 		struct got_parsed_tree_entry *pte = &entries[i];
1463 
1464 		/* Keep in sync with struct got_imsg_tree_object definition! */
1465 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1)
1466 			return got_error_from_errno("imsg_add TREE_ENTRY");
1467 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1)
1468 			return got_error_from_errno("imsg_add TREE_ENTRY");
1469 		if (imsg_add(wbuf, &pte->namelen, sizeof(pte->namelen)) == -1)
1470 			return got_error_from_errno("imsg_add TREE_ENTRY");
1471 		
1472 		/* Remaining bytes are the entry's name. */
1473 		if (imsg_add(wbuf, pte->name, pte->namelen) == -1)
1474 			return got_error_from_errno("imsg_add TREE_ENTRY");
1475 	}
1476 
1477 	wbuf->fd = -1;
1478 	imsg_close(ibuf, wbuf);
1479 	return NULL;
1480 }
1481 
1482 static const struct got_error *
1483 send_tree_entries(struct imsgbuf *ibuf, struct got_parsed_tree_entry *entries,
1484     int nentries)
1485 {
1486 	const struct got_error *err = NULL;
1487 	int i, j;
1488 	size_t entries_len = sizeof(struct got_imsg_tree_entries);
1489 
1490 	i = 0;
1491 	for (j = 0; j < nentries; j++) {
1492 		struct got_parsed_tree_entry *pte = &entries[j];
1493 		size_t len = sizeof(*pte) + pte->namelen;
1494 
1495 		if (j > 0 &&
1496 		    entries_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1497 			err = send_tree_entries_batch(ibuf, entries,
1498 			    i, j - 1, entries_len);
1499 			if (err)
1500 				return err;
1501 			i = j;
1502 			entries_len = sizeof(struct got_imsg_tree_entries);
1503 		}
1504 
1505 		entries_len += len;
1506 	}
1507 
1508 	if (j > 0) {
1509 		err = send_tree_entries_batch(ibuf, entries, i, j - 1,
1510 		    entries_len);
1511 		if (err)
1512 			return err;
1513 	}
1514 
1515 	return NULL;
1516 }
1517 
1518 const struct got_error *
1519 got_privsep_send_tree(struct imsgbuf *ibuf,
1520     struct got_parsed_tree_entry *entries, int nentries)
1521 {
1522 	const struct got_error *err = NULL;
1523 	struct got_imsg_tree_object itree;
1524 
1525 	itree.nentries = nentries;
1526 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1527 	    == -1)
1528 		return got_error_from_errno("imsg_compose TREE");
1529 
1530 	err = send_tree_entries(ibuf, entries, nentries);
1531 	if (err)
1532 		return err;
1533 
1534 	return flush_imsg(ibuf);
1535 }
1536 
1537 
1538 static const struct got_error *
1539 recv_tree_entries(void *data, size_t datalen, struct got_tree_object *tree,
1540     int *nentries)
1541 {
1542 	const struct got_error *err = NULL;
1543 	struct got_imsg_tree_entries *ientries;
1544 	struct got_tree_entry *te;
1545 	size_t te_offset;
1546 	size_t i;
1547 
1548 	if (datalen <= sizeof(*ientries) ||
1549 	    datalen > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
1550 		return got_error(GOT_ERR_PRIVSEP_LEN);
1551 
1552 	ientries = (struct got_imsg_tree_entries *)data;
1553 	if (ientries->nentries > INT_MAX) {
1554 		return got_error_msg(GOT_ERR_NO_SPACE,
1555 		    "too many tree entries");
1556 	}
1557 
1558 	te_offset = sizeof(*ientries);
1559 	for (i = 0; i < ientries->nentries; i++) {
1560 		struct got_imsg_tree_entry ite;
1561 		const char *te_name;
1562 		uint8_t *buf = (uint8_t *)data + te_offset;
1563 
1564 		if (te_offset >= datalen) {
1565 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1566 			break;
1567 		}
1568 
1569 		/* Might not be aligned, size is ~32 bytes. */
1570 		memcpy(&ite, buf, sizeof(ite));
1571 
1572 		if (ite.namelen >= sizeof(te->name)) {
1573 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1574 			break;
1575 		}
1576 		if (te_offset + sizeof(ite) + ite.namelen > datalen) {
1577 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1578 			break;
1579 		}
1580 
1581 		if (*nentries >= tree->nentries) {
1582 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1583 			break;
1584 		}
1585 		te = &tree->entries[*nentries];
1586 		te_name = buf + sizeof(ite);
1587 		memcpy(te->name, te_name, ite.namelen);
1588 		te->name[ite.namelen] = '\0';
1589 		memcpy(te->id.sha1, ite.id, SHA1_DIGEST_LENGTH);
1590 		te->mode = ite.mode;
1591 		te->idx = *nentries;
1592 		(*nentries)++;
1593 
1594 		te_offset += sizeof(ite) + ite.namelen;
1595 	}
1596 
1597 	return err;
1598 }
1599 
1600 const struct got_error *
1601 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1602 {
1603 	const struct got_error *err = NULL;
1604 	const size_t min_datalen =
1605 	    MIN(sizeof(struct got_imsg_error),
1606 	    sizeof(struct got_imsg_tree_object));
1607 	struct got_imsg_tree_object *itree;
1608 	int nentries = 0;
1609 
1610 	*tree = NULL;
1611 
1612 	err = read_imsg(ibuf);
1613 	if (err)
1614 		goto done;
1615 
1616 	for (;;) {
1617 		struct imsg imsg;
1618 		size_t n;
1619 		size_t datalen;
1620 
1621 		n = imsg_get(ibuf, &imsg);
1622 		if (n == 0) {
1623 			if ((*tree)) {
1624 				if (nentries < (*tree)->nentries) {
1625 					err = read_imsg(ibuf);
1626 					if (err)
1627 						break;
1628 					continue;
1629 				} else
1630 					break;
1631 			} else {
1632 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1633 				break;
1634 			}
1635 		}
1636 
1637 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen) {
1638 			imsg_free(&imsg);
1639 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1640 			break;
1641 		}
1642 
1643 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1644 
1645 		switch (imsg.hdr.type) {
1646 		case GOT_IMSG_ERROR:
1647 			err = recv_imsg_error(&imsg, datalen);
1648 			break;
1649 		case GOT_IMSG_TREE:
1650 			/* This message should only appear once. */
1651 			if (*tree != NULL) {
1652 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1653 				break;
1654 			}
1655 			if (datalen != sizeof(*itree)) {
1656 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1657 				break;
1658 			}
1659 			itree = imsg.data;
1660 			if (itree->nentries < 0) {
1661 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1662 				break;
1663 			}
1664 			*tree = malloc(sizeof(**tree));
1665 			if (*tree == NULL) {
1666 				err = got_error_from_errno("malloc");
1667 				break;
1668 			}
1669 			(*tree)->entries = calloc(itree->nentries,
1670 			    sizeof(struct got_tree_entry));
1671 			if ((*tree)->entries == NULL) {
1672 				err = got_error_from_errno("malloc");
1673 				free(*tree);
1674 				*tree = NULL;
1675 				break;
1676 			}
1677 			(*tree)->nentries = itree->nentries;
1678 			(*tree)->refcnt = 0;
1679 			break;
1680 		case GOT_IMSG_TREE_ENTRIES:
1681 			/* This message should be preceeded by GOT_IMSG_TREE. */
1682 			if (*tree == NULL) {
1683 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1684 				break;
1685 			}
1686 			err = recv_tree_entries(imsg.data, datalen,
1687 			    *tree, &nentries);
1688 			break;
1689 		default:
1690 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1691 			break;
1692 		}
1693 
1694 		imsg_free(&imsg);
1695 		if (err)
1696 			break;
1697 	}
1698 done:
1699 	if (*tree && (*tree)->nentries != nentries) {
1700 		if (err == NULL)
1701 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1702 		got_object_tree_close(*tree);
1703 		*tree = NULL;
1704 	}
1705 
1706 	return err;
1707 }
1708 
1709 const struct got_error *
1710 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1711     const uint8_t *data)
1712 {
1713 	struct got_imsg_blob iblob;
1714 
1715 	iblob.size = size;
1716 	iblob.hdrlen = hdrlen;
1717 
1718 	if (data) {
1719 		uint8_t *buf;
1720 
1721 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1722 			return got_error(GOT_ERR_NO_SPACE);
1723 
1724 		buf = malloc(sizeof(iblob) + size);
1725 		if (buf == NULL)
1726 			return got_error_from_errno("malloc");
1727 
1728 		memcpy(buf, &iblob, sizeof(iblob));
1729 		memcpy(buf + sizeof(iblob), data, size);
1730 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1731 		    sizeof(iblob) + size) == -1) {
1732 			free(buf);
1733 			return got_error_from_errno("imsg_compose BLOB");
1734 		}
1735 		free(buf);
1736 	} else {
1737 		/* Data has already been written to file descriptor. */
1738 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1739 		    sizeof(iblob)) == -1)
1740 			return got_error_from_errno("imsg_compose BLOB");
1741 	}
1742 
1743 
1744 	return flush_imsg(ibuf);
1745 }
1746 
1747 const struct got_error *
1748 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1749     struct imsgbuf *ibuf)
1750 {
1751 	const struct got_error *err = NULL;
1752 	struct imsg imsg;
1753 	struct got_imsg_blob *iblob;
1754 	size_t datalen;
1755 
1756 	*outbuf = NULL;
1757 
1758 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1759 	if (err)
1760 		return err;
1761 
1762 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1763 
1764 	switch (imsg.hdr.type) {
1765 	case GOT_IMSG_BLOB:
1766 		if (datalen < sizeof(*iblob)) {
1767 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1768 			break;
1769 		}
1770 		iblob = imsg.data;
1771 		*size = iblob->size;
1772 		*hdrlen = iblob->hdrlen;
1773 
1774 		if (datalen == sizeof(*iblob)) {
1775 			/* Data has been written to file descriptor. */
1776 			break;
1777 		}
1778 
1779 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX) {
1780 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1781 			break;
1782 		}
1783 
1784 		*outbuf = malloc(*size);
1785 		if (*outbuf == NULL) {
1786 			err = got_error_from_errno("malloc");
1787 			break;
1788 		}
1789 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1790 		break;
1791 	default:
1792 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1793 		break;
1794 	}
1795 
1796 	imsg_free(&imsg);
1797 
1798 	return err;
1799 }
1800 
1801 static const struct got_error *
1802 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1803 {
1804 	const struct got_error *err = NULL;
1805 	size_t offset, remain;
1806 
1807 	offset = 0;
1808 	remain = tagmsg_len;
1809 	while (remain > 0) {
1810 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1811 
1812 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1813 		    tag->tagmsg + offset, n) == -1) {
1814 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1815 			break;
1816 		}
1817 
1818 		err = flush_imsg(ibuf);
1819 		if (err)
1820 			break;
1821 
1822 		offset += n;
1823 		remain -= n;
1824 	}
1825 
1826 	return err;
1827 }
1828 
1829 const struct got_error *
1830 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1831 {
1832 	const struct got_error *err = NULL;
1833 	struct got_imsg_tag_object *itag;
1834 	uint8_t *buf;
1835 	size_t len, total;
1836 	size_t tag_len = strlen(tag->tag);
1837 	size_t tagger_len = strlen(tag->tagger);
1838 	size_t tagmsg_len = strlen(tag->tagmsg);
1839 
1840 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1841 
1842 	buf = malloc(total);
1843 	if (buf == NULL)
1844 		return got_error_from_errno("malloc");
1845 
1846 	itag = (struct got_imsg_tag_object *)buf;
1847 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1848 	itag->obj_type = tag->obj_type;
1849 	itag->tag_len = tag_len;
1850 	itag->tagger_len = tagger_len;
1851 	itag->tagger_time = tag->tagger_time;
1852 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1853 	itag->tagmsg_len = tagmsg_len;
1854 
1855 	len = sizeof(*itag);
1856 	memcpy(buf + len, tag->tag, tag_len);
1857 	len += tag_len;
1858 	memcpy(buf + len, tag->tagger, tagger_len);
1859 	len += tagger_len;
1860 
1861 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1862 		err = got_error_from_errno("imsg_compose TAG");
1863 		goto done;
1864 	}
1865 
1866 	if (tagmsg_len == 0 ||
1867 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1868 		err = flush_imsg(ibuf);
1869 		if (err)
1870 			goto done;
1871 	}
1872 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1873 done:
1874 	free(buf);
1875 	return err;
1876 }
1877 
1878 const struct got_error *
1879 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1880 {
1881 	const struct got_error *err = NULL;
1882 	struct imsg imsg;
1883 	struct got_imsg_tag_object *itag;
1884 	size_t len, datalen;
1885 	const size_t min_datalen =
1886 	    MIN(sizeof(struct got_imsg_error),
1887 	    sizeof(struct got_imsg_tag_object));
1888 
1889 	*tag = NULL;
1890 
1891 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1892 	if (err)
1893 		return err;
1894 
1895 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1896 	len = 0;
1897 
1898 	switch (imsg.hdr.type) {
1899 	case GOT_IMSG_TAG:
1900 		if (datalen < sizeof(*itag)) {
1901 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1902 			break;
1903 		}
1904 		itag = imsg.data;
1905 		if (datalen != sizeof(*itag) + itag->tag_len +
1906 		    itag->tagger_len) {
1907 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1908 			break;
1909 		}
1910 		len += sizeof(*itag);
1911 
1912 		*tag = calloc(1, sizeof(**tag));
1913 		if (*tag == NULL) {
1914 			err = got_error_from_errno("calloc");
1915 			break;
1916 		}
1917 
1918 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1919 
1920 		if (itag->tag_len == 0) {
1921 			(*tag)->tag = strdup("");
1922 			if ((*tag)->tag == NULL) {
1923 				err = got_error_from_errno("strdup");
1924 				break;
1925 			}
1926 		} else {
1927 			(*tag)->tag = malloc(itag->tag_len + 1);
1928 			if ((*tag)->tag == NULL) {
1929 				err = got_error_from_errno("malloc");
1930 				break;
1931 			}
1932 			memcpy((*tag)->tag, imsg.data + len,
1933 			    itag->tag_len);
1934 			(*tag)->tag[itag->tag_len] = '\0';
1935 		}
1936 		len += itag->tag_len;
1937 
1938 		(*tag)->obj_type = itag->obj_type;
1939 		(*tag)->tagger_time = itag->tagger_time;
1940 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1941 
1942 		if (itag->tagger_len == 0) {
1943 			(*tag)->tagger = strdup("");
1944 			if ((*tag)->tagger == NULL) {
1945 				err = got_error_from_errno("strdup");
1946 				break;
1947 			}
1948 		} else {
1949 			(*tag)->tagger = malloc(itag->tagger_len + 1);
1950 			if ((*tag)->tagger == NULL) {
1951 				err = got_error_from_errno("malloc");
1952 				break;
1953 			}
1954 			memcpy((*tag)->tagger, imsg.data + len,
1955 			    itag->tagger_len);
1956 			(*tag)->tagger[itag->tagger_len] = '\0';
1957 		}
1958 		len += itag->tagger_len;
1959 
1960 		if (itag->tagmsg_len == 0) {
1961 			(*tag)->tagmsg = strdup("");
1962 			if ((*tag)->tagmsg == NULL) {
1963 				err = got_error_from_errno("strdup");
1964 				break;
1965 			}
1966 		} else {
1967 			size_t offset = 0, remain = itag->tagmsg_len;
1968 
1969 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1970 			if ((*tag)->tagmsg == NULL) {
1971 				err = got_error_from_errno("malloc");
1972 				break;
1973 			}
1974 			while (remain > 0) {
1975 				struct imsg imsg_log;
1976 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1977 				    remain);
1978 
1979 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1980 				if (err)
1981 					return err;
1982 
1983 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1984 					return got_error(GOT_ERR_PRIVSEP_MSG);
1985 
1986 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1987 				    n);
1988 				imsg_free(&imsg_log);
1989 				offset += n;
1990 				remain -= n;
1991 			}
1992 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1993 		}
1994 
1995 		break;
1996 	default:
1997 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1998 		break;
1999 	}
2000 
2001 	imsg_free(&imsg);
2002 
2003 	return err;
2004 }
2005 
2006 const struct got_error *
2007 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
2008     struct got_packidx *packidx)
2009 {
2010 	const struct got_error *err = NULL;
2011 	struct got_imsg_packidx ipackidx;
2012 	struct got_imsg_pack ipack;
2013 	int fd;
2014 
2015 	ipackidx.len = packidx->len;
2016 	ipackidx.packfile_size = pack->filesize;
2017 	fd = dup(packidx->fd);
2018 	if (fd == -1)
2019 		return got_error_from_errno("dup");
2020 
2021 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
2022 	    sizeof(ipackidx)) == -1) {
2023 		err = got_error_from_errno("imsg_compose PACKIDX");
2024 		close(fd);
2025 		return err;
2026 	}
2027 
2028 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
2029 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
2030 		return got_error(GOT_ERR_NO_SPACE);
2031 	ipack.filesize = pack->filesize;
2032 
2033 	fd = dup(pack->fd);
2034 	if (fd == -1)
2035 		return got_error_from_errno("dup");
2036 
2037 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
2038 	    == -1) {
2039 		err = got_error_from_errno("imsg_compose PACK");
2040 		close(fd);
2041 		return err;
2042 	}
2043 
2044 	return flush_imsg(ibuf);
2045 }
2046 
2047 const struct got_error *
2048 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
2049     struct got_object_id *id)
2050 {
2051 	struct got_imsg_packed_object iobj;
2052 
2053 	iobj.idx = idx;
2054 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2055 
2056 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
2057 	    &iobj, sizeof(iobj)) == -1)
2058 		return got_error_from_errno("imsg_compose "
2059 		    "PACKED_OBJECT_REQUEST");
2060 
2061 	return flush_imsg(ibuf);
2062 }
2063 
2064 const struct got_error *
2065 got_privsep_send_packed_raw_obj_req(struct imsgbuf *ibuf, int idx,
2066     struct got_object_id *id)
2067 {
2068 	struct got_imsg_packed_object iobj;
2069 
2070 	iobj.idx = idx;
2071 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2072 
2073 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_RAW_OBJECT_REQUEST, 0, 0, -1,
2074 	    &iobj, sizeof(iobj)) == -1)
2075 		return got_error_from_errno("imsg_compose "
2076 		    "PACKED_OBJECT_REQUEST");
2077 
2078 	return flush_imsg(ibuf);
2079 }
2080 
2081 const struct got_error *
2082 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
2083 {
2084 	const struct got_error *err = NULL;
2085 
2086 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
2087 	    NULL, 0) == -1) {
2088 		err = got_error_from_errno("imsg_compose "
2089 		    "GITCONFIG_PARSE_REQUEST");
2090 		close(fd);
2091 		return err;
2092 	}
2093 
2094 	return flush_imsg(ibuf);
2095 }
2096 
2097 const struct got_error *
2098 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
2099 {
2100 	if (imsg_compose(ibuf,
2101 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
2102 	    NULL, 0) == -1)
2103 		return got_error_from_errno("imsg_compose "
2104 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
2105 
2106 	return flush_imsg(ibuf);
2107 }
2108 
2109 const struct got_error *
2110 got_privsep_send_gitconfig_repository_extensions_req(struct imsgbuf *ibuf)
2111 {
2112 	if (imsg_compose(ibuf,
2113 	    GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST, 0, 0, -1,
2114 	    NULL, 0) == -1)
2115 		return got_error_from_errno("imsg_compose "
2116 		    "GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST");
2117 
2118 	return flush_imsg(ibuf);
2119 }
2120 
2121 
2122 const struct got_error *
2123 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
2124 {
2125 	if (imsg_compose(ibuf,
2126 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
2127 		return got_error_from_errno("imsg_compose "
2128 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
2129 
2130 	return flush_imsg(ibuf);
2131 }
2132 
2133 const struct got_error *
2134 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
2135 {
2136 	if (imsg_compose(ibuf,
2137 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
2138 		return got_error_from_errno("imsg_compose "
2139 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
2140 
2141 	return flush_imsg(ibuf);
2142 }
2143 
2144 const struct got_error *
2145 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
2146 {
2147 	if (imsg_compose(ibuf,
2148 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2149 		return got_error_from_errno("imsg_compose "
2150 		    "GITCONFIG_REMOTE_REQUEST");
2151 
2152 	return flush_imsg(ibuf);
2153 }
2154 
2155 const struct got_error *
2156 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
2157 {
2158 	if (imsg_compose(ibuf,
2159 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
2160 		return got_error_from_errno("imsg_compose "
2161 		    "GITCONFIG_OWNER_REQUEST");
2162 
2163 	return flush_imsg(ibuf);
2164 }
2165 
2166 const struct got_error *
2167 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
2168 {
2169 	const struct got_error *err = NULL;
2170 	struct imsg imsg;
2171 	size_t datalen;
2172 	const size_t min_datalen = 0;
2173 
2174 	*str = NULL;
2175 
2176 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2177 	if (err)
2178 		return err;
2179 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2180 
2181 	switch (imsg.hdr.type) {
2182 	case GOT_IMSG_GITCONFIG_STR_VAL:
2183 		if (datalen == 0)
2184 			break;
2185 		/* datalen does not include terminating \0 */
2186 		*str = malloc(datalen + 1);
2187 		if (*str == NULL) {
2188 			err = got_error_from_errno("malloc");
2189 			break;
2190 		}
2191 		memcpy(*str, imsg.data, datalen);
2192 		(*str)[datalen] = '\0';
2193 		break;
2194 	default:
2195 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2196 		break;
2197 	}
2198 
2199 	imsg_free(&imsg);
2200 	return err;
2201 }
2202 
2203 const struct got_error *
2204 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
2205 {
2206 	const struct got_error *err = NULL;
2207 	struct imsg imsg;
2208 	size_t datalen;
2209 	const size_t min_datalen =
2210 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
2211 
2212 	*val = 0;
2213 
2214 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2215 	if (err)
2216 		return err;
2217 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2218 
2219 	switch (imsg.hdr.type) {
2220 	case GOT_IMSG_GITCONFIG_INT_VAL:
2221 		if (datalen != sizeof(*val)) {
2222 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2223 			break;
2224 		}
2225 		memcpy(val, imsg.data, sizeof(*val));
2226 		break;
2227 	default:
2228 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2229 		break;
2230 	}
2231 
2232 	imsg_free(&imsg);
2233 	return err;
2234 }
2235 
2236 static void
2237 free_remote_data(struct got_remote_repo *remote)
2238 {
2239 	int i;
2240 
2241 	free(remote->name);
2242 	free(remote->fetch_url);
2243 	free(remote->send_url);
2244 	for (i = 0; i < remote->nfetch_branches; i++)
2245 		free(remote->fetch_branches[i]);
2246 	free(remote->fetch_branches);
2247 	for (i = 0; i < remote->nsend_branches; i++)
2248 		free(remote->send_branches[i]);
2249 	free(remote->send_branches);
2250 	for (i = 0; i < remote->nfetch_refs; i++)
2251 		free(remote->fetch_refs[i]);
2252 	free(remote->fetch_refs);
2253 }
2254 
2255 const struct got_error *
2256 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
2257     int *nremotes, struct imsgbuf *ibuf)
2258 {
2259 	const struct got_error *err = NULL;
2260 	struct imsg imsg;
2261 	size_t datalen;
2262 	struct got_imsg_remotes iremotes;
2263 	struct got_imsg_remote iremote;
2264 
2265 	*remotes = NULL;
2266 	*nremotes = 0;
2267 	iremotes.nremotes = 0;
2268 
2269 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
2270 	if (err)
2271 		return err;
2272 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2273 
2274 	switch (imsg.hdr.type) {
2275 	case GOT_IMSG_GITCONFIG_REMOTES:
2276 		if (datalen != sizeof(iremotes)) {
2277 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2278 			break;
2279 		}
2280 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2281 		if (iremotes.nremotes == 0) {
2282 			imsg_free(&imsg);
2283 			return NULL;
2284 		}
2285 		break;
2286 	default:
2287 		imsg_free(&imsg);
2288 		return got_error(GOT_ERR_PRIVSEP_MSG);
2289 	}
2290 
2291 	imsg_free(&imsg);
2292 
2293 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2294 	if (*remotes == NULL)
2295 		return got_error_from_errno("recallocarray");
2296 
2297 	while (*nremotes < iremotes.nremotes) {
2298 		struct got_remote_repo *remote;
2299 
2300 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
2301 		if (err)
2302 			break;
2303 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2304 
2305 		switch (imsg.hdr.type) {
2306 		case GOT_IMSG_GITCONFIG_REMOTE:
2307 			remote = &(*remotes)[*nremotes];
2308 			memset(remote, 0, sizeof(*remote));
2309 			if (datalen < sizeof(iremote)) {
2310 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2311 				break;
2312 			}
2313 			memcpy(&iremote, imsg.data, sizeof(iremote));
2314 			if (iremote.name_len == 0 ||
2315 			    iremote.fetch_url_len == 0 ||
2316 			    iremote.send_url_len == 0 ||
2317 			    (sizeof(iremote) + iremote.name_len +
2318 			    iremote.fetch_url_len + iremote.send_url_len) > datalen) {
2319 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2320 				break;
2321 			}
2322 			remote->name = strndup(imsg.data + sizeof(iremote),
2323 			    iremote.name_len);
2324 			if (remote->name == NULL) {
2325 				err = got_error_from_errno("strndup");
2326 				break;
2327 			}
2328 			remote->fetch_url = strndup(imsg.data + sizeof(iremote) +
2329 			    iremote.name_len, iremote.fetch_url_len);
2330 			if (remote->fetch_url == NULL) {
2331 				err = got_error_from_errno("strndup");
2332 				free_remote_data(remote);
2333 				break;
2334 			}
2335 			remote->send_url = strndup(imsg.data + sizeof(iremote) +
2336 			    iremote.name_len + iremote.fetch_url_len,
2337 			    iremote.send_url_len);
2338 			if (remote->send_url == NULL) {
2339 				err = got_error_from_errno("strndup");
2340 				free_remote_data(remote);
2341 				break;
2342 			}
2343 			remote->mirror_references = iremote.mirror_references;
2344 			remote->fetch_all_branches = iremote.fetch_all_branches;
2345 			remote->nfetch_branches = 0;
2346 			remote->fetch_branches = NULL;
2347 			remote->nsend_branches = 0;
2348 			remote->send_branches = NULL;
2349 			remote->nfetch_refs = 0;
2350 			remote->fetch_refs = NULL;
2351 			(*nremotes)++;
2352 			break;
2353 		default:
2354 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2355 			break;
2356 		}
2357 
2358 		imsg_free(&imsg);
2359 		if (err)
2360 			break;
2361 	}
2362 
2363 	if (err) {
2364 		int i;
2365 		for (i = 0; i < *nremotes; i++)
2366 			free_remote_data(&(*remotes)[i]);
2367 		free(*remotes);
2368 		*remotes = NULL;
2369 		*nremotes = 0;
2370 	}
2371 	return err;
2372 }
2373 
2374 const struct got_error *
2375 got_privsep_send_gotconfig_parse_req(struct imsgbuf *ibuf, int fd)
2376 {
2377 	const struct got_error *err = NULL;
2378 
2379 	if (imsg_compose(ibuf, GOT_IMSG_GOTCONFIG_PARSE_REQUEST, 0, 0, fd,
2380 	    NULL, 0) == -1) {
2381 		err = got_error_from_errno("imsg_compose "
2382 		    "GOTCONFIG_PARSE_REQUEST");
2383 		close(fd);
2384 		return err;
2385 	}
2386 
2387 	return flush_imsg(ibuf);
2388 }
2389 
2390 const struct got_error *
2391 got_privsep_send_gotconfig_author_req(struct imsgbuf *ibuf)
2392 {
2393 	if (imsg_compose(ibuf,
2394 	    GOT_IMSG_GOTCONFIG_AUTHOR_REQUEST, 0, 0, -1, NULL, 0) == -1)
2395 		return got_error_from_errno("imsg_compose "
2396 		    "GOTCONFIG_AUTHOR_REQUEST");
2397 
2398 	return flush_imsg(ibuf);
2399 }
2400 
2401 const struct got_error *
2402 got_privsep_send_gotconfig_remotes_req(struct imsgbuf *ibuf)
2403 {
2404 	if (imsg_compose(ibuf,
2405 	    GOT_IMSG_GOTCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2406 		return got_error_from_errno("imsg_compose "
2407 		    "GOTCONFIG_REMOTE_REQUEST");
2408 
2409 	return flush_imsg(ibuf);
2410 }
2411 
2412 const struct got_error *
2413 got_privsep_recv_gotconfig_str(char **str, struct imsgbuf *ibuf)
2414 {
2415 	const struct got_error *err = NULL;
2416 	struct imsg imsg;
2417 	size_t datalen;
2418 	const size_t min_datalen = 0;
2419 
2420 	*str = NULL;
2421 
2422 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2423 	if (err)
2424 		return err;
2425 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2426 
2427 	switch (imsg.hdr.type) {
2428 	case GOT_IMSG_ERROR:
2429 		if (datalen < sizeof(struct got_imsg_error)) {
2430 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2431 			break;
2432 		}
2433 		err = recv_imsg_error(&imsg, datalen);
2434 		break;
2435 	case GOT_IMSG_GOTCONFIG_STR_VAL:
2436 		if (datalen == 0)
2437 			break;
2438 		/* datalen does not include terminating \0 */
2439 		*str = malloc(datalen + 1);
2440 		if (*str == NULL) {
2441 			err = got_error_from_errno("malloc");
2442 			break;
2443 		}
2444 		memcpy(*str, imsg.data, datalen);
2445 		(*str)[datalen] = '\0';
2446 		break;
2447 	default:
2448 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2449 		break;
2450 	}
2451 
2452 	imsg_free(&imsg);
2453 	return err;
2454 }
2455 
2456 const struct got_error *
2457 got_privsep_recv_gotconfig_remotes(struct got_remote_repo **remotes,
2458     int *nremotes, struct imsgbuf *ibuf)
2459 {
2460 	const struct got_error *err = NULL;
2461 	struct imsg imsg;
2462 	size_t datalen;
2463 	struct got_imsg_remotes iremotes;
2464 	struct got_imsg_remote iremote;
2465 	const size_t min_datalen =
2466 	    MIN(sizeof(struct got_imsg_error), sizeof(iremotes));
2467 
2468 	*remotes = NULL;
2469 	*nremotes = 0;
2470 	iremotes.nremotes = 0;
2471 
2472 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2473 	if (err)
2474 		return err;
2475 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2476 
2477 	switch (imsg.hdr.type) {
2478 	case GOT_IMSG_ERROR:
2479 		if (datalen < sizeof(struct got_imsg_error)) {
2480 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2481 			break;
2482 		}
2483 		err = recv_imsg_error(&imsg, datalen);
2484 		break;
2485 	case GOT_IMSG_GOTCONFIG_REMOTES:
2486 		if (datalen != sizeof(iremotes)) {
2487 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2488 			break;
2489 		}
2490 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2491 		if (iremotes.nremotes == 0) {
2492 			imsg_free(&imsg);
2493 			return NULL;
2494 		}
2495 		break;
2496 	default:
2497 		imsg_free(&imsg);
2498 		return got_error(GOT_ERR_PRIVSEP_MSG);
2499 	}
2500 
2501 	imsg_free(&imsg);
2502 
2503 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2504 	if (*remotes == NULL)
2505 		return got_error_from_errno("recallocarray");
2506 
2507 	while (*nremotes < iremotes.nremotes) {
2508 		struct got_remote_repo *remote;
2509 		const size_t min_datalen =
2510 		    MIN(sizeof(struct got_imsg_error), sizeof(iremote));
2511 		int i;
2512 
2513 		err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2514 		if (err)
2515 			break;
2516 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2517 
2518 		switch (imsg.hdr.type) {
2519 		case GOT_IMSG_ERROR:
2520 			if (datalen < sizeof(struct got_imsg_error)) {
2521 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2522 				break;
2523 			}
2524 			err = recv_imsg_error(&imsg, datalen);
2525 			break;
2526 		case GOT_IMSG_GOTCONFIG_REMOTE:
2527 			remote = &(*remotes)[*nremotes];
2528 			memset(remote, 0, sizeof(*remote));
2529 			if (datalen < sizeof(iremote)) {
2530 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2531 				break;
2532 			}
2533 			memcpy(&iremote, imsg.data, sizeof(iremote));
2534 			if (iremote.name_len == 0 ||
2535 			    (iremote.fetch_url_len == 0 &&
2536 			    iremote.send_url_len == 0) ||
2537 			    (sizeof(iremote) + iremote.name_len +
2538 			    iremote.fetch_url_len + iremote.send_url_len) >
2539 			    datalen) {
2540 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2541 				break;
2542 			}
2543 			remote->name = strndup(imsg.data + sizeof(iremote),
2544 			    iremote.name_len);
2545 			if (remote->name == NULL) {
2546 				err = got_error_from_errno("strndup");
2547 				break;
2548 			}
2549 			remote->fetch_url = strndup(imsg.data +
2550 			    sizeof(iremote) + iremote.name_len,
2551 			    iremote.fetch_url_len);
2552 			if (remote->fetch_url == NULL) {
2553 				err = got_error_from_errno("strndup");
2554 				free_remote_data(remote);
2555 				break;
2556 			}
2557 			remote->send_url = strndup(imsg.data +
2558 			    sizeof(iremote) + iremote.name_len +
2559 			    iremote.fetch_url_len, iremote.send_url_len);
2560 			if (remote->send_url == NULL) {
2561 				err = got_error_from_errno("strndup");
2562 				free_remote_data(remote);
2563 				break;
2564 			}
2565 			remote->mirror_references = iremote.mirror_references;
2566 			remote->fetch_all_branches = iremote.fetch_all_branches;
2567 			if (iremote.nfetch_branches > 0) {
2568 				remote->fetch_branches = recallocarray(NULL, 0,
2569 				    iremote.nfetch_branches, sizeof(char *));
2570 				if (remote->fetch_branches == NULL) {
2571 					err = got_error_from_errno("calloc");
2572 					free_remote_data(remote);
2573 					break;
2574 				}
2575 			}
2576 			remote->nfetch_branches = 0;
2577 			for (i = 0; i < iremote.nfetch_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->fetch_branches[i] = branch;
2586 				remote->nfetch_branches++;
2587 			}
2588 			if (iremote.nsend_branches > 0) {
2589 				remote->send_branches = recallocarray(NULL, 0,
2590 				    iremote.nsend_branches, sizeof(char *));
2591 				if (remote->send_branches == NULL) {
2592 					err = got_error_from_errno("calloc");
2593 					free_remote_data(remote);
2594 					break;
2595 				}
2596 			}
2597 			remote->nsend_branches = 0;
2598 			for (i = 0; i < iremote.nsend_branches; i++) {
2599 				char *branch;
2600 				err = got_privsep_recv_gotconfig_str(&branch,
2601 				    ibuf);
2602 				if (err) {
2603 					free_remote_data(remote);
2604 					goto done;
2605 				}
2606 				remote->send_branches[i] = branch;
2607 				remote->nsend_branches++;
2608 			}
2609 			if (iremote.nfetch_refs > 0) {
2610 				remote->fetch_refs = recallocarray(NULL, 0,
2611 				    iremote.nfetch_refs, sizeof(char *));
2612 				if (remote->fetch_refs == NULL) {
2613 					err = got_error_from_errno("calloc");
2614 					free_remote_data(remote);
2615 					break;
2616 				}
2617 			}
2618 			remote->nfetch_refs = 0;
2619 			for (i = 0; i < iremote.nfetch_refs; i++) {
2620 				char *ref;
2621 				err = got_privsep_recv_gotconfig_str(&ref,
2622 				    ibuf);
2623 				if (err) {
2624 					free_remote_data(remote);
2625 					goto done;
2626 				}
2627 				remote->fetch_refs[i] = ref;
2628 				remote->nfetch_refs++;
2629 			}
2630 			(*nremotes)++;
2631 			break;
2632 		default:
2633 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2634 			break;
2635 		}
2636 
2637 		imsg_free(&imsg);
2638 		if (err)
2639 			break;
2640 	}
2641 done:
2642 	if (err) {
2643 		int i;
2644 		for (i = 0; i < *nremotes; i++)
2645 			free_remote_data(&(*remotes)[i]);
2646 		free(*remotes);
2647 		*remotes = NULL;
2648 		*nremotes = 0;
2649 	}
2650 	return err;
2651 }
2652 
2653 const struct got_error *
2654 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
2655     struct got_object_id *id, int idx, const char *path)
2656 {
2657 	struct ibuf *wbuf;
2658 	size_t path_len = strlen(path) + 1;
2659 
2660 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
2661 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
2662 	if (wbuf == NULL)
2663 		return got_error_from_errno(
2664 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
2665 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1)
2666 		return got_error_from_errno("imsg_add "
2667 		    "COMMIT_TRAVERSAL_REQUEST");
2668 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1)
2669 		return got_error_from_errno("imsg_add "
2670 		    "COMMIT_TRAVERSAL_REQUEST");
2671 	if (imsg_add(wbuf, path, path_len) == -1)
2672 		return got_error_from_errno("imsg_add "
2673 		    "COMMIT_TRAVERSAL_REQUEST");
2674 
2675 	wbuf->fd = -1;
2676 	imsg_close(ibuf, wbuf);
2677 
2678 	return flush_imsg(ibuf);
2679 }
2680 
2681 const struct got_error *
2682 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
2683     struct got_object_id **changed_commit_id,
2684     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
2685 {
2686 	const struct got_error *err = NULL;
2687 	struct imsg imsg;
2688 	struct got_imsg_traversed_commits *icommits;
2689 	size_t datalen;
2690 	int i, done = 0;
2691 
2692 	*changed_commit = NULL;
2693 	*changed_commit_id = NULL;
2694 
2695 	while (!done) {
2696 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2697 		if (err)
2698 			return err;
2699 
2700 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2701 		switch (imsg.hdr.type) {
2702 		case GOT_IMSG_TRAVERSED_COMMITS:
2703 			icommits = imsg.data;
2704 			if (datalen != sizeof(*icommits) +
2705 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
2706 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2707 				break;
2708 			}
2709 			for (i = 0; i < icommits->ncommits; i++) {
2710 				struct got_object_qid *qid;
2711 				uint8_t *sha1 = (uint8_t *)imsg.data +
2712 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
2713 				err = got_object_qid_alloc_partial(&qid);
2714 				if (err)
2715 					break;
2716 				memcpy(qid->id.sha1, sha1, SHA1_DIGEST_LENGTH);
2717 				STAILQ_INSERT_TAIL(commit_ids, qid, entry);
2718 
2719 				/* The last commit may contain a change. */
2720 				if (i == icommits->ncommits - 1) {
2721 					*changed_commit_id =
2722 					    got_object_id_dup(&qid->id);
2723 					if (*changed_commit_id == NULL) {
2724 						err = got_error_from_errno(
2725 						    "got_object_id_dup");
2726 						break;
2727 					}
2728 				}
2729 			}
2730 			break;
2731 		case GOT_IMSG_COMMIT:
2732 			if (*changed_commit_id == NULL) {
2733 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2734 				break;
2735 			}
2736 			err = get_commit_from_imsg(changed_commit, &imsg,
2737 			    datalen, ibuf);
2738 			break;
2739 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
2740 			done = 1;
2741 			break;
2742 		default:
2743 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2744 			break;
2745 		}
2746 
2747 		imsg_free(&imsg);
2748 		if (err)
2749 			break;
2750 	}
2751 
2752 	if (err)
2753 		got_object_id_queue_free(commit_ids);
2754 	return err;
2755 }
2756 
2757 const struct got_error *
2758 got_privsep_send_enumerated_tree(size_t *totlen, struct imsgbuf *ibuf,
2759     struct got_object_id *tree_id, const char *path,
2760     struct got_parsed_tree_entry *entries, int nentries)
2761 {
2762 	const struct got_error *err = NULL;
2763 	struct ibuf *wbuf;
2764 	size_t path_len = strlen(path);
2765 	size_t msglen;
2766 
2767 	msglen = sizeof(struct got_imsg_enumerated_tree) + path_len;
2768 	wbuf = imsg_create(ibuf, GOT_IMSG_ENUMERATED_TREE, 0, 0, msglen);
2769 	if (wbuf == NULL)
2770 		return got_error_from_errno("imsg_create ENUMERATED_TREE");
2771 
2772 	if (imsg_add(wbuf, tree_id->sha1, SHA1_DIGEST_LENGTH) == -1)
2773 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2774 	if (imsg_add(wbuf, &nentries, sizeof(nentries)) == -1)
2775 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2776 	if (imsg_add(wbuf, path, path_len) == -1)
2777 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2778 
2779 	wbuf->fd = -1;
2780 	imsg_close(ibuf, wbuf);
2781 
2782 	if (entries) {
2783 		err = send_tree_entries(ibuf, entries, nentries);
2784 		if (err)
2785 			return err;
2786 	}
2787 
2788 	return flush_imsg(ibuf);
2789 }
2790 
2791 const struct got_error *
2792 got_privsep_send_object_enumeration_request(struct imsgbuf *ibuf)
2793 {
2794 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_REQUEST,
2795 	    0, 0, -1, NULL, 0) == -1)
2796 		return got_error_from_errno("imsg_compose "
2797 		    "OBJECT_ENUMERATION_REQUEST");
2798 
2799 	return flush_imsg(ibuf);
2800 }
2801 
2802 const struct got_error *
2803 got_privsep_send_object_enumeration_done(struct imsgbuf *ibuf)
2804 {
2805 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_DONE,
2806 	    0, 0, -1, NULL, 0) == -1)
2807 		return got_error_from_errno("imsg_compose "
2808 		    "OBJECT_ENUMERATION_DONE");
2809 
2810 	return flush_imsg(ibuf);
2811 }
2812 
2813 const struct got_error *
2814 got_privsep_send_enumerated_commit(struct imsgbuf *ibuf,
2815     struct got_object_id *id, time_t mtime)
2816 {
2817 	struct ibuf *wbuf;
2818 
2819 	wbuf = imsg_create(ibuf, GOT_IMSG_ENUMERATED_COMMIT, 0, 0,
2820 	    sizeof(struct got_imsg_enumerated_commit) + SHA1_DIGEST_LENGTH);
2821 	if (wbuf == NULL)
2822 		return got_error_from_errno("imsg_create ENUMERATED_COMMIT");
2823 
2824 	/* Keep in sync with struct got_imsg_enumerated_commit! */
2825 	if (imsg_add(wbuf, id, SHA1_DIGEST_LENGTH) == -1)
2826 		return got_error_from_errno("imsg_add ENUMERATED_COMMIT");
2827 	if (imsg_add(wbuf, &mtime, sizeof(mtime)) == -1)
2828 		return got_error_from_errno("imsg_add ENUMERATED_COMMIT");
2829 
2830 	wbuf->fd = -1;
2831 	imsg_close(ibuf, wbuf);
2832 	/* Don't flush yet, tree entries or ENUMERATION_DONE will follow. */
2833 	return NULL;
2834 }
2835 
2836 const struct got_error *
2837 got_privsep_recv_enumerated_objects(struct imsgbuf *ibuf,
2838     got_object_enumerate_commit_cb cb_commit,
2839     got_object_enumerate_tree_cb cb_tree, void *cb_arg,
2840     struct got_repository *repo)
2841 {
2842 	const struct got_error *err = NULL;
2843 	struct imsg imsg;
2844 	struct got_imsg_enumerated_commit *icommit = NULL;
2845 	struct got_object_id commit_id;
2846 	int have_commit = 0;
2847 	time_t mtime = 0;
2848 	struct got_tree_object tree;
2849 	struct got_imsg_enumerated_tree *itree;
2850 	struct got_object_id tree_id;
2851 	char *path = NULL, *canon_path = NULL;
2852 	size_t datalen, path_len;
2853 	int nentries = -1;
2854 	int done = 0;
2855 
2856 	memset(&tree, 0, sizeof(tree));
2857 
2858 	while (!done) {
2859 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2860 		if (err)
2861 			break;
2862 
2863 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2864 		switch (imsg.hdr.type) {
2865 		case GOT_IMSG_ENUMERATED_COMMIT: 
2866 			if (have_commit && nentries != -1) {
2867 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2868 				break;
2869 			}
2870 			if (datalen != sizeof(*icommit)) {
2871 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2872 				break;
2873 			}
2874 			icommit = (struct got_imsg_enumerated_commit *)imsg.data;
2875 			memcpy(commit_id.sha1, icommit->id, SHA1_DIGEST_LENGTH);
2876 			mtime = icommit->mtime;
2877 			have_commit = 1;
2878 			break;
2879 		case GOT_IMSG_ENUMERATED_TREE:
2880 			/* Should be preceeded by GOT_IMSG_ENUMERATED_COMMIT. */
2881 			if (!have_commit) {
2882 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2883 				break;
2884 			}
2885 			if (datalen < sizeof(*itree)) {
2886 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2887 				break;
2888 			}
2889 			itree = imsg.data;
2890 			path_len = datalen - sizeof(*itree);
2891 			if (path_len == 0) {
2892 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2893 				break;
2894 			}
2895 			memcpy(tree_id.sha1, itree->id, sizeof(tree_id.sha1));
2896 			free(path);
2897 			path = malloc(path_len + 1);
2898 			if (path == NULL) {
2899 				err = got_error_from_errno("malloc");
2900 				break;
2901 			}
2902 			free(canon_path);
2903 			canon_path = malloc(path_len + 1);
2904 			if (canon_path == NULL) {
2905 				err = got_error_from_errno("malloc");
2906 				break;
2907 			}
2908 			memcpy(path, (uint8_t *)imsg.data + sizeof(*itree),
2909 			    path_len);
2910 			path[path_len] = '\0';
2911 			if (!got_path_is_absolute(path)) {
2912 				err = got_error(GOT_ERR_BAD_PATH);
2913 				break;
2914 			}
2915 			if (got_path_is_root_dir(path)) {
2916 				/* XXX check what got_canonpath() does wrong */
2917 				canon_path[0] = '/';
2918 				canon_path[1] = '\0';
2919 			} else {
2920 				err = got_canonpath(path, canon_path,
2921 				    path_len + 1);
2922 				if (err)
2923 					break;
2924 			}
2925 			if (strcmp(path, canon_path) != 0) {
2926 				err = got_error(GOT_ERR_BAD_PATH);
2927 				break;
2928 			}
2929 			if (nentries != -1) {
2930 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2931 				break;
2932 			}
2933 			if (itree->nentries < -1) {
2934 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2935 				break;
2936 			}
2937 			if (itree->nentries == -1) {
2938 				/* Tree was not found in pack file. */
2939 				done = 1;
2940 				err = cb_tree(cb_arg, NULL, mtime, &tree_id,
2941 				    path, repo);
2942 				break;
2943 			}
2944 			if (itree->nentries > INT_MAX) {
2945 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2946 				break;
2947 			}
2948 			tree.entries = calloc(itree->nentries,
2949 			    sizeof(struct got_tree_entry));
2950 			if (tree.entries == NULL) {
2951 				err = got_error_from_errno("calloc");
2952 				break;
2953 			}
2954 			if (itree->nentries == 0) {
2955 				err = cb_tree(cb_arg, &tree, mtime, &tree_id,
2956 				    path, repo);
2957 				if (err)
2958 					break;
2959 
2960 				/* Prepare for next tree. */
2961 				free(tree.entries);
2962 				memset(&tree, 0, sizeof(tree));
2963 				nentries = -1;
2964 			} else {
2965 				tree.nentries = itree->nentries;
2966 				nentries = 0;
2967 			}
2968 			break;
2969 		case GOT_IMSG_TREE_ENTRIES:
2970 			/* Should be preceeded by GOT_IMSG_ENUMERATED_TREE. */
2971 			if (nentries <= -1) {
2972 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2973 				break;
2974 			}
2975 			err = recv_tree_entries(imsg.data, datalen,
2976 			    &tree, &nentries);
2977 			if (err)
2978 				break;
2979 			if (tree.nentries == nentries) {
2980 				err = cb_tree(cb_arg, &tree, mtime, &tree_id,
2981 				    path, repo);
2982 				if (err)
2983 					break;
2984 
2985 				/* Prepare for next tree. */
2986 				free(tree.entries);
2987 				memset(&tree, 0, sizeof(tree));
2988 				nentries = -1;
2989 			}
2990 			break;
2991 		case GOT_IMSG_TREE_ENUMERATION_DONE:
2992 			/* All trees have been found and traversed. */
2993 			if (!have_commit || path == NULL || nentries != -1) {
2994 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2995 				break;
2996 			}
2997 			err = cb_commit(cb_arg, mtime, &commit_id, repo);
2998 			if (err)
2999 				break;
3000 			have_commit = 0;
3001 			break;
3002 		case GOT_IMSG_OBJECT_ENUMERATION_DONE:
3003 			done = 1;
3004 			break;
3005 		default:
3006 			err = got_error(GOT_ERR_PRIVSEP_MSG);
3007 			break;
3008 		}
3009 
3010 		imsg_free(&imsg);
3011 		if (err)
3012 			break;
3013 	}
3014 
3015 	free(path);
3016 	free(canon_path);
3017 	free(tree.entries);
3018 	return err;
3019 }
3020 
3021 const struct got_error *
3022 got_privsep_send_raw_delta_req(struct imsgbuf *ibuf, int idx,
3023     struct got_object_id *id)
3024 {
3025 	struct got_imsg_raw_delta_request dreq;
3026 
3027 	dreq.idx = idx;
3028 	memcpy(dreq.id, id->sha1, SHA1_DIGEST_LENGTH);
3029 
3030 	if (imsg_compose(ibuf, GOT_IMSG_RAW_DELTA_REQUEST, 0, 0, -1,
3031 	    &dreq, sizeof(dreq)) == -1)
3032 		return got_error_from_errno("imsg_compose RAW_DELTA_REQUEST");
3033 
3034 	return flush_imsg(ibuf);
3035 }
3036 
3037 const struct got_error *
3038 got_privsep_send_raw_delta_outfd(struct imsgbuf *ibuf, int fd)
3039 {
3040 	return send_fd(ibuf, GOT_IMSG_RAW_DELTA_OUTFD, fd);
3041 }
3042 
3043 const struct got_error *
3044 got_privsep_send_raw_delta(struct imsgbuf *ibuf, uint64_t base_size,
3045     uint64_t result_size,  off_t delta_size, off_t delta_compressed_size,
3046     off_t delta_offset, off_t delta_out_offset, struct got_object_id *base_id)
3047 {
3048 	struct got_imsg_raw_delta idelta;
3049 	int ret;
3050 
3051 	idelta.base_size = base_size;
3052 	idelta.result_size = result_size;
3053 	idelta.delta_size = delta_size;
3054 	idelta.delta_compressed_size = delta_compressed_size;
3055 	idelta.delta_offset = delta_offset;
3056 	idelta.delta_out_offset = delta_out_offset;
3057 	memcpy(idelta.base_id, base_id->sha1, SHA1_DIGEST_LENGTH);
3058 
3059 	ret = imsg_compose(ibuf, GOT_IMSG_RAW_DELTA, 0, 0, -1,
3060 	    &idelta, sizeof(idelta));
3061 	if (ret == -1)
3062 		return got_error_from_errno("imsg_compose RAW_DELTA");
3063 
3064 	return flush_imsg(ibuf);
3065 }
3066 
3067 const struct got_error *
3068 got_privsep_recv_raw_delta(uint64_t *base_size, uint64_t *result_size,
3069     off_t *delta_size, off_t *delta_compressed_size, off_t *delta_offset,
3070     off_t *delta_out_offset, struct got_object_id **base_id, struct imsgbuf *ibuf)
3071 {
3072 	const struct got_error *err = NULL;
3073 	struct imsg imsg;
3074 	struct got_imsg_raw_delta *delta;
3075 	size_t datalen;
3076 
3077 	*base_size = 0;
3078 	*result_size = 0;
3079 	*delta_size = 0;
3080 	*delta_compressed_size = 0;
3081 	*delta_offset = 0;
3082 	*delta_out_offset = 0;
3083 	*base_id = NULL;
3084 
3085 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3086 	if (err)
3087 		return err;
3088 
3089 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3090 
3091 	switch (imsg.hdr.type) {
3092 	case GOT_IMSG_RAW_DELTA:
3093 		if (datalen != sizeof(*delta)) {
3094 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3095 			break;
3096 		}
3097 		delta = imsg.data;
3098 		*base_size = delta->base_size;
3099 		*result_size = delta->result_size;
3100 		*delta_size = delta->delta_size;
3101 		*delta_compressed_size = delta->delta_compressed_size;
3102 		*delta_offset = delta->delta_offset;
3103 		*delta_out_offset = delta->delta_out_offset;
3104 		*base_id = calloc(1, sizeof(**base_id));
3105 		if (*base_id == NULL) {
3106 			err = got_error_from_errno("malloc");
3107 			break;
3108 		}
3109 		memcpy((*base_id)->sha1, delta->base_id, SHA1_DIGEST_LENGTH);
3110 		break;
3111 	default:
3112 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3113 		break;
3114 	}
3115 
3116 	imsg_free(&imsg);
3117 
3118 	if (err) {
3119 		free(*base_id);
3120 		*base_id = NULL;
3121 	}
3122 	return err;
3123 }
3124 
3125 static const struct got_error *
3126 send_idlist(struct imsgbuf *ibuf, struct got_object_id **ids, size_t nids)
3127 {
3128 	const struct got_error *err = NULL;
3129 	struct got_imsg_object_idlist idlist;
3130 	struct ibuf *wbuf;
3131 	size_t i;
3132 
3133 	if (nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS)
3134 		return got_error(GOT_ERR_NO_SPACE);
3135 
3136 	wbuf = imsg_create(ibuf, GOT_IMSG_OBJ_ID_LIST, 0, 0,
3137 	    sizeof(idlist) + nids * sizeof(**ids));
3138 	if (wbuf == NULL) {
3139 		err = got_error_from_errno("imsg_create OBJ_ID_LIST");
3140 		return err;
3141 	}
3142 
3143 	idlist.nids = nids;
3144 	if (imsg_add(wbuf, &idlist, sizeof(idlist)) == -1)
3145 		return got_error_from_errno("imsg_add OBJ_ID_LIST");
3146 
3147 	for (i = 0; i < nids; i++) {
3148 		struct got_object_id *id = ids[i];
3149 		if (imsg_add(wbuf, id, sizeof(*id)) == -1)
3150 			return got_error_from_errno("imsg_add OBJ_ID_LIST");
3151 	}
3152 	
3153 	wbuf->fd = -1;
3154 	imsg_close(ibuf, wbuf);
3155 
3156 	return flush_imsg(ibuf);
3157 }
3158 
3159 const struct got_error *
3160 got_privsep_send_object_idlist(struct imsgbuf *ibuf,
3161     struct got_object_id **ids, size_t nids)
3162 {
3163 	const struct got_error *err = NULL;
3164 	struct got_object_id *idlist[GOT_IMSG_OBJ_ID_LIST_MAX_NIDS];
3165 	int i, j = 0;
3166 
3167 	for (i = 0; i < nids; i++) { 
3168 		j = i % nitems(idlist);
3169 		idlist[j] = ids[i];
3170 		if (j >= nitems(idlist) - 1) {
3171 			err = send_idlist(ibuf, idlist, j + 1);
3172 			if (err)
3173 				return err;
3174 			j = 0;
3175 		}
3176 	}
3177 
3178 	if (j > 0) {
3179 		err = send_idlist(ibuf, idlist, j + 1);
3180 		if (err)
3181 			return err;
3182 	}
3183 
3184 	return NULL;
3185 }
3186 
3187 const struct got_error *
3188 got_privsep_send_object_idlist_done(struct imsgbuf *ibuf)
3189 {
3190 	if (imsg_compose(ibuf, GOT_IMSG_OBJ_ID_LIST_DONE, 0, 0, -1, NULL, 0)
3191 	    == -1)
3192 		return got_error_from_errno("imsg_compose OBJ_ID_LIST_DONE");
3193 
3194 	return flush_imsg(ibuf);
3195 }
3196 
3197 const struct got_error *
3198 got_privsep_recv_object_idlist(int *done, struct got_object_id **ids,
3199     size_t *nids, struct imsgbuf *ibuf)
3200 {
3201 	const struct got_error *err = NULL;
3202 	struct imsg imsg;
3203 	struct got_imsg_object_idlist *idlist;
3204 	size_t datalen;
3205 
3206 	*ids = NULL;
3207 	*done = 0;
3208 	*nids = 0;
3209 
3210 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3211 	if (err)
3212 		return err;
3213 
3214 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3215 	switch (imsg.hdr.type) {
3216 	case GOT_IMSG_OBJ_ID_LIST:
3217 		if (datalen < sizeof(*idlist)) {
3218 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3219 			break;
3220 		}
3221 		idlist = imsg.data;
3222 		if (idlist->nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS) {
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 	if (ndeltas > GOT_IMSG_REUSED_DELTAS_MAX_NDELTAS)
3268 		return got_error(GOT_ERR_NO_SPACE);
3269 
3270 	wbuf = imsg_create(ibuf, GOT_IMSG_REUSED_DELTAS, 0, 0,
3271 	    sizeof(ideltas) + ndeltas * sizeof(*deltas));
3272 	if (wbuf == NULL) {
3273 		err = got_error_from_errno("imsg_create REUSED_DELTAS");
3274 		return err;
3275 	}
3276 
3277 	ideltas.ndeltas = ndeltas;
3278 	if (imsg_add(wbuf, &ideltas, sizeof(ideltas)) == -1)
3279 		return got_error_from_errno("imsg_add REUSED_DELTAS");
3280 
3281 	for (i = 0; i < ndeltas; i++) {
3282 		struct got_imsg_reused_delta *delta = &deltas[i];
3283 		if (imsg_add(wbuf, delta, sizeof(*delta)) == -1)
3284 			return got_error_from_errno("imsg_add REUSED_DELTAS");
3285 	}
3286 	
3287 	wbuf->fd = -1;
3288 	imsg_close(ibuf, wbuf);
3289 
3290 	return flush_imsg(ibuf);
3291 }
3292 
3293 const struct got_error *
3294 got_privsep_send_reused_deltas_done(struct imsgbuf *ibuf)
3295 {
3296 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_DONE, 0, 0, -1, NULL, 0)
3297 	    == -1)
3298 		return got_error_from_errno("imsg_compose DELTA_REUSE_DONE");
3299 
3300 	return flush_imsg(ibuf);
3301 }
3302 
3303 const struct got_error *
3304 got_privsep_recv_reused_deltas(int *done, struct got_imsg_reused_delta *deltas,
3305     size_t *ndeltas, struct imsgbuf *ibuf)
3306 {
3307 	const struct got_error *err = NULL;
3308 	struct imsg imsg;
3309 	struct got_imsg_reused_deltas *ideltas;
3310 	size_t datalen;
3311 
3312 	*done = 0;
3313 	*ndeltas = 0;
3314 
3315 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3316 	if (err)
3317 		return err;
3318 
3319 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3320 	switch (imsg.hdr.type) {
3321 	case GOT_IMSG_REUSED_DELTAS:
3322 		if (datalen < sizeof(*ideltas)) {
3323 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3324 			break;
3325 		}
3326 		ideltas = imsg.data;
3327 		if (ideltas->ndeltas > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS) {
3328 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3329 			break;
3330 		}
3331 		*ndeltas = ideltas->ndeltas;
3332 		memcpy(deltas, (uint8_t *)imsg.data + sizeof(ideltas),
3333 		    *ndeltas * sizeof(*deltas));
3334 		break;
3335 	case GOT_IMSG_DELTA_REUSE_DONE:
3336 		*done = 1;
3337 		break;
3338 	default:
3339 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3340 		break;
3341 	}
3342 
3343 	imsg_free(&imsg);
3344 
3345 	return err;
3346 }
3347 
3348 const struct got_error *
3349 got_privsep_unveil_exec_helpers(void)
3350 {
3351 	const char *helpers[] = {
3352 	    GOT_PATH_PROG_READ_PACK,
3353 	    GOT_PATH_PROG_READ_OBJECT,
3354 	    GOT_PATH_PROG_READ_COMMIT,
3355 	    GOT_PATH_PROG_READ_TREE,
3356 	    GOT_PATH_PROG_READ_BLOB,
3357 	    GOT_PATH_PROG_READ_TAG,
3358 	    GOT_PATH_PROG_READ_GITCONFIG,
3359 	    GOT_PATH_PROG_READ_GOTCONFIG,
3360 	    GOT_PATH_PROG_READ_PATCH,
3361 	    GOT_PATH_PROG_FETCH_PACK,
3362 	    GOT_PATH_PROG_INDEX_PACK,
3363 	    GOT_PATH_PROG_SEND_PACK,
3364 	};
3365 	size_t i;
3366 
3367 	for (i = 0; i < nitems(helpers); i++) {
3368 		if (unveil(helpers[i], "x") == 0)
3369 			continue;
3370 		return got_error_from_errno2("unveil", helpers[i]);
3371 	}
3372 
3373 	return NULL;
3374 }
3375 
3376 void
3377 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
3378 {
3379 	if (close(imsg_fds[0]) == -1) {
3380 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3381 		_exit(1);
3382 	}
3383 
3384 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
3385 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3386 		_exit(1);
3387 	}
3388 
3389 	closefrom(GOT_IMSG_FD_CHILD + 1);
3390 
3391 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
3392 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
3393 		    strerror(errno));
3394 		_exit(1);
3395 	}
3396 }