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 #include "got_privsep.h"
52 
53 #ifndef MIN
54 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
55 #endif
56 
57 #ifndef nitems
58 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
59 #endif
60 
61 static const struct got_error *
62 poll_fd(int fd, int events, int timeout)
63 {
64 	struct pollfd pfd[1];
65 	struct timespec ts;
66 	sigset_t sigset;
67 	int n;
68 
69 	pfd[0].fd = fd;
70 	pfd[0].events = events;
71 
72 	ts.tv_sec = timeout;
73 	ts.tv_nsec = 0;
74 
75 	if (sigemptyset(&sigset) == -1)
76 		return got_error_from_errno("sigemptyset");
77 	if (sigaddset(&sigset, SIGWINCH) == -1)
78 		return got_error_from_errno("sigaddset");
79 
80 	n = ppoll(pfd, 1, timeout == INFTIM ? NULL : &ts, &sigset);
81 	if (n == -1)
82 		return got_error_from_errno("ppoll");
83 	if (n == 0)
84 		return got_error(GOT_ERR_TIMEOUT);
85 	if (pfd[0].revents & (POLLERR | POLLNVAL))
86 		return got_error_from_errno("poll error");
87 	if (pfd[0].revents & (events | POLLHUP))
88 		return NULL;
89 
90 	return got_error(GOT_ERR_INTERRUPT);
91 }
92 
93 static const struct got_error *
94 read_imsg(struct imsgbuf *ibuf)
95 {
96 	const struct got_error *err;
97 	size_t n;
98 
99 	err = poll_fd(ibuf->fd, POLLIN, INFTIM);
100 	if (err)
101 		return err;
102 
103 	n = imsg_read(ibuf);
104 	if (n == -1) {
105 		if (errno == EAGAIN) /* Could be a file-descriptor leak. */
106 			return got_error(GOT_ERR_PRIVSEP_NO_FD);
107 		return got_error(GOT_ERR_PRIVSEP_READ);
108 	}
109 	if (n == 0)
110 		return got_error(GOT_ERR_PRIVSEP_PIPE);
111 
112 	return NULL;
113 }
114 
115 const struct got_error *
116 got_privsep_wait_for_child(pid_t pid)
117 {
118 	int child_status;
119 
120 	if (waitpid(pid, &child_status, 0) == -1)
121 		return got_error_from_errno("waitpid");
122 
123 	if (!WIFEXITED(child_status))
124 		return got_error(GOT_ERR_PRIVSEP_DIED);
125 
126 	if (WEXITSTATUS(child_status) != 0)
127 		return got_error(GOT_ERR_PRIVSEP_EXIT);
128 
129 	return NULL;
130 }
131 
132 static const struct got_error *
133 recv_imsg_error(struct imsg *imsg, size_t datalen)
134 {
135 	struct got_imsg_error *ierr;
136 
137 	if (datalen != sizeof(*ierr))
138 		return got_error(GOT_ERR_PRIVSEP_LEN);
139 
140 	ierr = imsg->data;
141 	if (ierr->code == GOT_ERR_ERRNO) {
142 		static struct got_error serr;
143 		serr.code = GOT_ERR_ERRNO;
144 		serr.msg = strerror(ierr->errno_code);
145 		return &serr;
146 	}
147 
148 	return got_error(ierr->code);
149 }
150 
151 const struct got_error *
152 got_privsep_recv_imsg(struct imsg *imsg, struct imsgbuf *ibuf,
153     size_t min_datalen)
154 {
155 	const struct got_error *err;
156 	ssize_t n;
157 
158 	n = imsg_get(ibuf, imsg);
159 	if (n == -1)
160 		return got_error_from_errno("imsg_get");
161 
162 	while (n == 0) {
163 		err = read_imsg(ibuf);
164 		if (err)
165 			return err;
166 		n = imsg_get(ibuf, imsg);
167 		if (n == -1)
168 			return got_error_from_errno("imsg_get");
169 	}
170 
171 	if (imsg->hdr.len < IMSG_HEADER_SIZE + min_datalen)
172 		return got_error(GOT_ERR_PRIVSEP_LEN);
173 
174 	if (imsg->hdr.type == GOT_IMSG_ERROR) {
175 		size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
176 		return recv_imsg_error(imsg, datalen);
177 	}
178 
179 	return NULL;
180 }
181 
182 /* Attempt to send an error in an imsg. Complain on stderr as a last resort. */
183 void
184 got_privsep_send_error(struct imsgbuf *ibuf, const struct got_error *err)
185 {
186 	const struct got_error *poll_err;
187 	struct got_imsg_error ierr;
188 	int ret;
189 
190 	ierr.code = err->code;
191 	if (err->code == GOT_ERR_ERRNO)
192 		ierr.errno_code = errno;
193 	else
194 		ierr.errno_code = 0;
195 	ret = imsg_compose(ibuf, GOT_IMSG_ERROR, 0, 0, -1, &ierr, sizeof(ierr));
196 	if (ret == -1) {
197 		fprintf(stderr, "%s: error %d \"%s\": imsg_compose: %s\n",
198 		    getprogname(), err->code, err->msg, strerror(errno));
199 		return;
200 	}
201 
202 	poll_err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
203 	if (poll_err) {
204 		fprintf(stderr, "%s: error %d \"%s\": poll: %s\n",
205 		    getprogname(), err->code, err->msg, poll_err->msg);
206 		return;
207 	}
208 
209 	ret = imsg_flush(ibuf);
210 	if (ret == -1) {
211 		fprintf(stderr, "%s: error %d \"%s\": imsg_flush: %s\n",
212 		    getprogname(), err->code, err->msg, strerror(errno));
213 		imsg_clear(ibuf);
214 		return;
215 	}
216 }
217 
218 static const struct got_error *
219 flush_imsg(struct imsgbuf *ibuf)
220 {
221 	const struct got_error *err;
222 
223 	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
224 	if (err)
225 		return err;
226 
227 	if (imsg_flush(ibuf) == -1) {
228 		imsg_clear(ibuf);
229 		return got_error_from_errno("imsg_flush");
230 	}
231 
232 	return NULL;
233 }
234 
235 const struct got_error *
236 got_privsep_flush_imsg(struct imsgbuf *ibuf)
237 {
238 	return flush_imsg(ibuf);
239 }
240 
241 const struct got_error *
242 got_privsep_send_stop(int fd)
243 {
244 	const struct got_error *err = NULL;
245 	struct imsgbuf ibuf;
246 
247 	imsg_init(&ibuf, fd);
248 
249 	if (imsg_compose(&ibuf, GOT_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
250 		return got_error_from_errno("imsg_compose STOP");
251 
252 	err = flush_imsg(&ibuf);
253 	return err;
254 }
255 
256 const struct got_error *
257 got_privsep_send_obj_req(struct imsgbuf *ibuf, int fd,
258     struct got_object_id *id)
259 {
260 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_REQUEST, 0, 0, fd,
261 	    id, sizeof(*id)) == -1)
262 		return got_error_from_errno("imsg_compose OBJECT_REQUEST");
263 
264 	return flush_imsg(ibuf);
265 }
266 
267 const struct got_error *
268 got_privsep_send_raw_obj_req(struct imsgbuf *ibuf, int fd,
269     struct got_object_id *id)
270 {
271 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_REQUEST, 0, 0, fd,
272 	    id, sizeof(*id)) == -1)
273 		return got_error_from_errno("imsg_compose RAW_OBJECT_REQUEST");
274 
275 	return flush_imsg(ibuf);
276 }
277 
278 const struct got_error *
279 got_privsep_send_raw_obj_outfd(struct imsgbuf *ibuf, int outfd)
280 {
281 	const struct got_error *err = NULL;
282 
283 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_OUTFD, 0, 0, outfd, NULL, 0)
284 	    == -1) {
285 		err = got_error_from_errno("imsg_compose RAW_OBJECT_OUTFD");
286 		close(outfd);
287 		return err;
288 	}
289 
290 	return flush_imsg(ibuf);
291 }
292 
293 const struct got_error *
294 got_privsep_send_raw_obj(struct imsgbuf *ibuf, off_t size, size_t hdrlen,
295     uint8_t *data)
296 {
297 	const struct got_error *err = NULL;
298 	struct got_imsg_raw_obj iobj;
299 	size_t len = sizeof(iobj);
300 	struct ibuf *wbuf;
301 
302 	memset(&iobj, 0, sizeof(iobj));
303 	iobj.hdrlen = hdrlen;
304 	iobj.size = size;
305 
306 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX)
307 		len += (size_t)size + hdrlen;
308 
309 	wbuf = imsg_create(ibuf, GOT_IMSG_RAW_OBJECT, 0, 0, len);
310 	if (wbuf == NULL) {
311 		err = got_error_from_errno("imsg_create RAW_OBJECT");
312 		return err;
313 	}
314 
315 	if (imsg_add(wbuf, &iobj, sizeof(iobj)) == -1)
316 		return got_error_from_errno("imsg_add RAW_OBJECT");
317 
318 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
319 		if (imsg_add(wbuf, data, size + hdrlen) == -1)
320 			return got_error_from_errno("imsg_add RAW_OBJECT");
321 	}
322 
323 	wbuf->fd = -1;
324 	imsg_close(ibuf, wbuf);
325 
326 	return flush_imsg(ibuf);
327 }
328 
329 const struct got_error *
330 got_privsep_recv_raw_obj(uint8_t **outbuf, off_t *size, size_t *hdrlen,
331     struct imsgbuf *ibuf)
332 {
333 	const struct got_error *err = NULL;
334 	struct imsg imsg;
335 	struct got_imsg_raw_obj *iobj;
336 	size_t datalen;
337 
338 	*outbuf = NULL;
339 
340 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
341 	if (err)
342 		return err;
343 
344 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
345 
346 	switch (imsg.hdr.type) {
347 	case GOT_IMSG_RAW_OBJECT:
348 		if (datalen < sizeof(*iobj)) {
349 			err = got_error(GOT_ERR_PRIVSEP_LEN);
350 			break;
351 		}
352 		iobj = imsg.data;
353 		*size = iobj->size;
354 		*hdrlen = iobj->hdrlen;
355 
356 		if (datalen == sizeof(*iobj)) {
357 			/* Data has been written to file descriptor. */
358 			break;
359 		}
360 
361 		if (*size < 0 ||
362 		    *size + *hdrlen > GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
363 			err = got_error(GOT_ERR_PRIVSEP_LEN);
364 			break;
365 		}
366 
367 		*outbuf = malloc(*size + *hdrlen);
368 		if (*outbuf == NULL) {
369 			err = got_error_from_errno("malloc");
370 			break;
371 		}
372 		memcpy(*outbuf, imsg.data + sizeof(*iobj), *size + *hdrlen);
373 		break;
374 	default:
375 		err = got_error(GOT_ERR_PRIVSEP_MSG);
376 		break;
377 	}
378 
379 	imsg_free(&imsg);
380 
381 	return err;
382 }
383 
384 const struct got_error *
385 got_privsep_send_commit_req(struct imsgbuf *ibuf, int fd,
386     struct got_object_id *id, int pack_idx)
387 {
388 	const struct got_error *err = NULL;
389 	struct got_imsg_packed_object iobj;
390 	void *data;
391 	size_t len;
392 
393 	memset(&iobj, 0, sizeof(iobj));
394 	if (pack_idx != -1) { /* commit is packed */
395 		iobj.idx = pack_idx;
396 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
397 		data = &iobj;
398 		len = sizeof(iobj);
399 	} else {
400 		data = id;
401 		len = sizeof(*id);
402 	}
403 
404 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_REQUEST, 0, 0, fd, data, len)
405 	    == -1) {
406 		err = got_error_from_errno("imsg_compose COMMIT_REQUEST");
407 		close(fd);
408 		return err;
409 	}
410 
411 	return flush_imsg(ibuf);
412 }
413 
414 const struct got_error *
415 got_privsep_send_tree_req(struct imsgbuf *ibuf, int fd,
416     struct got_object_id *id, int pack_idx)
417 {
418 	struct ibuf *wbuf;
419 	size_t len;
420 
421 	if (pack_idx != -1)
422 		len = sizeof(struct got_imsg_packed_object);
423 	else
424 		len = sizeof(*id);
425 
426 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_REQUEST, 0, 0, len);
427 	if (wbuf == NULL)
428 		return got_error_from_errno("imsg_create TREE_REQUEST");
429 
430 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1)
431 		return got_error_from_errno("imsg_add TREE_REQUEST");
432 
433 	if (pack_idx != -1) { /* tree is packed */
434 		if (imsg_add(wbuf, &pack_idx, sizeof(pack_idx)) == -1)
435 			return got_error_from_errno("imsg_add TREE_REQUEST");
436 	}
437 
438 	wbuf->fd = fd;
439 	imsg_close(ibuf, wbuf);
440 
441 	return flush_imsg(ibuf);
442 }
443 
444 const struct got_error *
445 got_privsep_send_tag_req(struct imsgbuf *ibuf, int fd,
446     struct got_object_id *id, int pack_idx)
447 {
448 	struct got_imsg_packed_object iobj;
449 	void *data;
450 	size_t len;
451 
452 	memset(&iobj, 0, sizeof(iobj));
453 	if (pack_idx != -1) { /* tag is packed */
454 		iobj.idx = pack_idx;
455 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
456 		data = &iobj;
457 		len = sizeof(iobj);
458 	} else {
459 		data = id;
460 		len = sizeof(*id);
461 	}
462 
463 	if (imsg_compose(ibuf, GOT_IMSG_TAG_REQUEST, 0, 0, fd, data, len)
464 	    == -1)
465 		return got_error_from_errno("imsg_compose TAG_REQUEST");
466 
467 	return flush_imsg(ibuf);
468 }
469 
470 const struct got_error *
471 got_privsep_send_blob_req(struct imsgbuf *ibuf, int infd,
472     struct got_object_id *id, int pack_idx)
473 {
474 	const struct got_error *err = NULL;
475 	struct got_imsg_packed_object iobj;
476 	void *data;
477 	size_t len;
478 
479 	memset(&iobj, 0, sizeof(iobj));
480 	if (pack_idx != -1) { /* blob is packed */
481 		iobj.idx = pack_idx;
482 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
483 		data = &iobj;
484 		len = sizeof(iobj);
485 	} else {
486 		data = id;
487 		len = sizeof(*id);
488 	}
489 
490 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_REQUEST, 0, 0, infd, data, len)
491 	    == -1) {
492 		err = got_error_from_errno("imsg_compose BLOB_REQUEST");
493 		close(infd);
494 		return err;
495 	}
496 
497 	return flush_imsg(ibuf);
498 }
499 
500 const struct got_error *
501 got_privsep_send_blob_outfd(struct imsgbuf *ibuf, int outfd)
502 {
503 	const struct got_error *err = NULL;
504 
505 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_OUTFD, 0, 0, outfd, NULL, 0)
506 	    == -1) {
507 		err = got_error_from_errno("imsg_compose BLOB_OUTFD");
508 		close(outfd);
509 		return err;
510 	}
511 
512 	return flush_imsg(ibuf);
513 }
514 
515 static const struct got_error *
516 send_fd(struct imsgbuf *ibuf, int imsg_code, int fd)
517 {
518 	const struct got_error *err = NULL;
519 
520 	if (imsg_compose(ibuf, imsg_code, 0, 0, fd, NULL, 0) == -1) {
521 		err = got_error_from_errno("imsg_compose TMPFD");
522 		close(fd);
523 		return err;
524 	}
525 
526 	return flush_imsg(ibuf);
527 }
528 
529 const struct got_error *
530 got_privsep_send_tmpfd(struct imsgbuf *ibuf, int fd)
531 {
532 	return send_fd(ibuf, GOT_IMSG_TMPFD, fd);
533 }
534 
535 const struct got_error *
536 got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj)
537 {
538 	struct got_imsg_object iobj;
539 
540 	memset(&iobj, 0, sizeof(iobj));
541 
542 	memcpy(iobj.id, obj->id.sha1, sizeof(iobj.id));
543 	iobj.type = obj->type;
544 	iobj.flags = obj->flags;
545 	iobj.hdrlen = obj->hdrlen;
546 	iobj.size = obj->size;
547 	if (iobj.flags & GOT_OBJ_FLAG_PACKED) {
548 		iobj.pack_offset = obj->pack_offset;
549 		iobj.pack_idx = obj->pack_idx;
550 	}
551 
552 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
553 	    == -1)
554 		return got_error_from_errno("imsg_compose OBJECT");
555 
556 	return flush_imsg(ibuf);
557 }
558 
559 const struct got_error *
560 got_privsep_send_fetch_req(struct imsgbuf *ibuf, int fd,
561     struct got_pathlist_head *have_refs, int fetch_all_branches,
562     struct got_pathlist_head *wanted_branches,
563     struct got_pathlist_head *wanted_refs, int list_refs_only, int verbosity)
564 {
565 	const struct got_error *err = NULL;
566 	struct ibuf *wbuf;
567 	size_t len;
568 	struct got_pathlist_entry *pe;
569 	struct got_imsg_fetch_request fetchreq;
570 
571 	memset(&fetchreq, 0, sizeof(fetchreq));
572 	fetchreq.fetch_all_branches = fetch_all_branches;
573 	fetchreq.list_refs_only = list_refs_only;
574 	fetchreq.verbosity = verbosity;
575 	TAILQ_FOREACH(pe, have_refs, entry)
576 		fetchreq.n_have_refs++;
577 	TAILQ_FOREACH(pe, wanted_branches, entry)
578 		fetchreq.n_wanted_branches++;
579 	TAILQ_FOREACH(pe, wanted_refs, entry)
580 		fetchreq.n_wanted_refs++;
581 	len = sizeof(struct got_imsg_fetch_request);
582 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
583 		close(fd);
584 		return got_error(GOT_ERR_NO_SPACE);
585 	}
586 
587 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_REQUEST, 0, 0, fd,
588 	    &fetchreq, sizeof(fetchreq)) == -1)
589 		return got_error_from_errno(
590 		    "imsg_compose FETCH_SERVER_PROGRESS");
591 
592 	err = flush_imsg(ibuf);
593 	if (err) {
594 		close(fd);
595 		return err;
596 	}
597 	fd = -1;
598 
599 	TAILQ_FOREACH(pe, have_refs, entry) {
600 		const char *name = pe->path;
601 		size_t name_len = pe->path_len;
602 		struct got_object_id *id = pe->data;
603 
604 		len = sizeof(struct got_imsg_fetch_have_ref) + name_len;
605 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_HAVE_REF, 0, 0, len);
606 		if (wbuf == NULL)
607 			return got_error_from_errno("imsg_create FETCH_HAVE_REF");
608 
609 		/* Keep in sync with struct got_imsg_fetch_have_ref! */
610 		if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1)
611 			return got_error_from_errno("imsg_add FETCH_HAVE_REF");
612 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
613 			return got_error_from_errno("imsg_add FETCH_HAVE_REF");
614 		if (imsg_add(wbuf, name, name_len) == -1)
615 			return got_error_from_errno("imsg_add FETCH_HAVE_REF");
616 
617 		wbuf->fd = -1;
618 		imsg_close(ibuf, wbuf);
619 		err = flush_imsg(ibuf);
620 		if (err)
621 			return err;
622 	}
623 
624 	TAILQ_FOREACH(pe, wanted_branches, entry) {
625 		const char *name = pe->path;
626 		size_t name_len = pe->path_len;
627 
628 		len = sizeof(struct got_imsg_fetch_wanted_branch) + name_len;
629 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_BRANCH, 0, 0,
630 		    len);
631 		if (wbuf == NULL)
632 			return got_error_from_errno(
633 			    "imsg_create FETCH_WANTED_BRANCH");
634 
635 		/* Keep in sync with struct got_imsg_fetch_wanted_branch! */
636 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
637 			return got_error_from_errno(
638 			    "imsg_add FETCH_WANTED_BRANCH");
639 		if (imsg_add(wbuf, name, name_len) == -1)
640 			return got_error_from_errno(
641 			    "imsg_add FETCH_WANTED_BRANCH");
642 
643 		wbuf->fd = -1;
644 		imsg_close(ibuf, wbuf);
645 		err = flush_imsg(ibuf);
646 		if (err)
647 			return err;
648 	}
649 
650 	TAILQ_FOREACH(pe, wanted_refs, entry) {
651 		const char *name = pe->path;
652 		size_t name_len = pe->path_len;
653 
654 		len = sizeof(struct got_imsg_fetch_wanted_ref) + name_len;
655 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_REF, 0, 0,
656 		    len);
657 		if (wbuf == NULL)
658 			return got_error_from_errno(
659 			    "imsg_create FETCH_WANTED_REF");
660 
661 		/* Keep in sync with struct got_imsg_fetch_wanted_ref! */
662 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
663 			return got_error_from_errno(
664 			    "imsg_add FETCH_WANTED_REF");
665 		if (imsg_add(wbuf, name, name_len) == -1)
666 			return got_error_from_errno(
667 			    "imsg_add FETCH_WANTED_REF");
668 
669 		wbuf->fd = -1;
670 		imsg_close(ibuf, wbuf);
671 		err = flush_imsg(ibuf);
672 		if (err)
673 			return err;
674 	}
675 
676 
677 	return NULL;
678 
679 }
680 
681 const struct got_error *
682 got_privsep_send_fetch_outfd(struct imsgbuf *ibuf, int fd)
683 {
684 	return send_fd(ibuf, GOT_IMSG_FETCH_OUTFD, fd);
685 }
686 
687 const struct got_error *
688 got_privsep_recv_fetch_progress(int *done, struct got_object_id **id,
689     char **refname, struct got_pathlist_head *symrefs, char **server_progress,
690     off_t *packfile_size, uint8_t *pack_sha1, struct imsgbuf *ibuf)
691 {
692 	const struct got_error *err = NULL;
693 	struct imsg imsg;
694 	size_t datalen;
695 	struct got_imsg_fetch_symrefs *isymrefs = NULL;
696 	size_t n, remain;
697 	off_t off;
698 	int i;
699 
700 	*done = 0;
701 	*id = NULL;
702 	*refname = NULL;
703 	*server_progress = NULL;
704 	*packfile_size = 0;
705 	memset(pack_sha1, 0, SHA1_DIGEST_LENGTH);
706 
707 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
708 	if (err)
709 		return err;
710 
711 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
712 	switch (imsg.hdr.type) {
713 	case GOT_IMSG_ERROR:
714 		err = recv_imsg_error(&imsg, datalen);
715 		break;
716 	case GOT_IMSG_FETCH_SYMREFS:
717 		if (datalen < sizeof(*isymrefs)) {
718 			err = got_error(GOT_ERR_PRIVSEP_LEN);
719 			break;
720 		}
721 		if (isymrefs != NULL) {
722 			err = got_error(GOT_ERR_PRIVSEP_MSG);
723 			break;
724 		}
725 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
726 		off = sizeof(*isymrefs);
727 		remain = datalen - off;
728 		for (n = 0; n < isymrefs->nsymrefs; n++) {
729 			struct got_imsg_fetch_symref *s;
730 			char *name, *target;
731 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
732 				err = got_error(GOT_ERR_PRIVSEP_LEN);
733 				goto done;
734 			}
735 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
736 			off += sizeof(*s);
737 			remain -= sizeof(*s);
738 			if (remain < s->name_len) {
739 				err = got_error(GOT_ERR_PRIVSEP_LEN);
740 				goto done;
741 			}
742 			name = strndup(imsg.data + off, s->name_len);
743 			if (name == NULL) {
744 				err = got_error_from_errno("strndup");
745 				goto done;
746 			}
747 			off += s->name_len;
748 			remain -= s->name_len;
749 			if (remain < s->target_len) {
750 				err = got_error(GOT_ERR_PRIVSEP_LEN);
751 				free(name);
752 				goto done;
753 			}
754 			target = strndup(imsg.data + off, s->target_len);
755 			if (target == NULL) {
756 				err = got_error_from_errno("strndup");
757 				free(name);
758 				goto done;
759 			}
760 			off += s->target_len;
761 			remain -= s->target_len;
762 			err = got_pathlist_append(symrefs, name, target);
763 			if (err) {
764 				free(name);
765 				free(target);
766 				goto done;
767 			}
768 		}
769 		break;
770 	case GOT_IMSG_FETCH_REF:
771 		if (datalen <= SHA1_DIGEST_LENGTH) {
772 			err = got_error(GOT_ERR_PRIVSEP_MSG);
773 			break;
774 		}
775 		*id = malloc(sizeof(**id));
776 		if (*id == NULL) {
777 			err = got_error_from_errno("malloc");
778 			break;
779 		}
780 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
781 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
782 		    datalen - SHA1_DIGEST_LENGTH);
783 		if (*refname == NULL) {
784 			err = got_error_from_errno("strndup");
785 			break;
786 		}
787 		break;
788 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
789 		if (datalen == 0) {
790 			err = got_error(GOT_ERR_PRIVSEP_LEN);
791 			break;
792 		}
793 		*server_progress = strndup(imsg.data, datalen);
794 		if (*server_progress == NULL) {
795 			err = got_error_from_errno("strndup");
796 			break;
797 		}
798 		for (i = 0; i < datalen; i++) {
799 			if (!isprint((unsigned char)(*server_progress)[i]) &&
800 			    !isspace((unsigned char)(*server_progress)[i])) {
801 				err = got_error(GOT_ERR_PRIVSEP_MSG);
802 				free(*server_progress);
803 				*server_progress = NULL;
804 				goto done;
805 			}
806 		}
807 		break;
808 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
809 		if (datalen < sizeof(*packfile_size)) {
810 			err = got_error(GOT_ERR_PRIVSEP_MSG);
811 			break;
812 		}
813 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
814 		break;
815 	case GOT_IMSG_FETCH_DONE:
816 		if (datalen != SHA1_DIGEST_LENGTH) {
817 			err = got_error(GOT_ERR_PRIVSEP_MSG);
818 			break;
819 		}
820 		memcpy(pack_sha1, imsg.data, SHA1_DIGEST_LENGTH);
821 		*done = 1;
822 		break;
823 	default:
824 		err = got_error(GOT_ERR_PRIVSEP_MSG);
825 		break;
826 	}
827 done:
828 	if (err) {
829 		free(*id);
830 		*id = NULL;
831 		free(*refname);
832 		*refname = NULL;
833 	}
834 	imsg_free(&imsg);
835 	return err;
836 }
837 
838 static const struct got_error *
839 send_send_ref(const char *name, size_t name_len, struct got_object_id *id,
840     int delete, struct imsgbuf *ibuf)
841 {
842 	size_t len;
843 	struct ibuf *wbuf;
844 
845 	len = sizeof(struct got_imsg_send_ref) + name_len;
846 	wbuf = imsg_create(ibuf, GOT_IMSG_SEND_REF, 0, 0, len);
847 	if (wbuf == NULL)
848 		return got_error_from_errno("imsg_create SEND_REF");
849 
850 	/* Keep in sync with struct got_imsg_send_ref! */
851 	if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1)
852 		return got_error_from_errno("imsg_add SEND_REF");
853 	if (imsg_add(wbuf, &delete, sizeof(delete)) == -1)
854 		return got_error_from_errno("imsg_add SEND_REF");
855 	if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1)
856 		return got_error_from_errno("imsg_add SEND_REF");
857 	if (imsg_add(wbuf, name, name_len) == -1)
858 		return got_error_from_errno("imsg_add SEND_REF");
859 
860 	wbuf->fd = -1;
861 	imsg_close(ibuf, wbuf);
862 	return flush_imsg(ibuf);
863 }
864 
865 const struct got_error *
866 got_privsep_send_send_req(struct imsgbuf *ibuf, int fd,
867     struct got_pathlist_head *have_refs,
868     struct got_pathlist_head *delete_refs,
869     int verbosity)
870 {
871 	const struct got_error *err = NULL;
872 	struct got_pathlist_entry *pe;
873 	struct got_imsg_send_request sendreq;
874 	struct got_object_id zero_id;
875 
876 	memset(&zero_id, 0, sizeof(zero_id));
877 	memset(&sendreq, 0, sizeof(sendreq));
878 	sendreq.verbosity = verbosity;
879 	TAILQ_FOREACH(pe, have_refs, entry)
880 		sendreq.nrefs++;
881 	TAILQ_FOREACH(pe, delete_refs, entry)
882 		sendreq.nrefs++;
883 	if (imsg_compose(ibuf, GOT_IMSG_SEND_REQUEST, 0, 0, fd,
884 	    &sendreq, sizeof(sendreq)) == -1) {
885 		err = got_error_from_errno(
886 		    "imsg_compose FETCH_SERVER_PROGRESS");
887 		goto done;
888 	}
889 
890 	err = flush_imsg(ibuf);
891 	if (err)
892 		goto done;
893 	fd = -1;
894 
895 	TAILQ_FOREACH(pe, have_refs, entry) {
896 		const char *name = pe->path;
897 		size_t name_len = pe->path_len;
898 		struct got_object_id *id = pe->data;
899 		err = send_send_ref(name, name_len, id, 0, ibuf);
900 		if (err)
901 			goto done;
902 	}
903 
904 	TAILQ_FOREACH(pe, delete_refs, entry) {
905 		const char *name = pe->path;
906 		size_t name_len = pe->path_len;
907 		err = send_send_ref(name, name_len, &zero_id, 1, ibuf);
908 		if (err)
909 			goto done;
910 	}
911 done:
912 	if (fd != -1 && close(fd) == -1 && err == NULL)
913 		err = got_error_from_errno("close");
914 	return err;
915 
916 }
917 
918 const struct got_error *
919 got_privsep_recv_send_remote_refs(struct got_pathlist_head *remote_refs,
920     struct imsgbuf *ibuf)
921 {
922 	const struct got_error *err = NULL;
923 	struct imsg imsg;
924 	size_t datalen;
925 	int done = 0;
926 	struct got_imsg_send_remote_ref iremote_ref;
927 	struct got_object_id *id = NULL;
928 	char *refname = NULL;
929 	struct got_pathlist_entry *new;
930 
931 	while (!done) {
932 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
933 		if (err)
934 			return err;
935 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
936 		switch (imsg.hdr.type) {
937 		case GOT_IMSG_ERROR:
938 			err = recv_imsg_error(&imsg, datalen);
939 			goto done;
940 		case GOT_IMSG_SEND_REMOTE_REF:
941 			if (datalen < sizeof(iremote_ref)) {
942 				err = got_error(GOT_ERR_PRIVSEP_MSG);
943 				goto done;
944 			}
945 			memcpy(&iremote_ref, imsg.data, sizeof(iremote_ref));
946 			if (datalen != sizeof(iremote_ref) +
947 			    iremote_ref.name_len) {
948 				err = got_error(GOT_ERR_PRIVSEP_MSG);
949 				goto done;
950 			}
951 			id = malloc(sizeof(*id));
952 			if (id == NULL) {
953 				err = got_error_from_errno("malloc");
954 				goto done;
955 			}
956 			memcpy(id->sha1, iremote_ref.id, SHA1_DIGEST_LENGTH);
957 			refname = strndup(imsg.data + sizeof(iremote_ref),
958 			    datalen - sizeof(iremote_ref));
959 			if (refname == NULL) {
960 				err = got_error_from_errno("strndup");
961 				goto done;
962 			}
963 			err = got_pathlist_insert(&new, remote_refs,
964 			    refname, id);
965 			if (err)
966 				goto done;
967 			if (new == NULL) { /* duplicate which wasn't inserted */
968 				free(id);
969 				free(refname);
970 			}
971 			id = NULL;
972 			refname = NULL;
973 			break;
974 		case GOT_IMSG_SEND_PACK_REQUEST:
975 			if (datalen != 0) {
976 				err = got_error(GOT_ERR_PRIVSEP_MSG);
977 				goto done;
978 			}
979 			/* got-send-pack is now waiting for a pack file. */
980 			done = 1;
981 			break;
982 		default:
983 			err = got_error(GOT_ERR_PRIVSEP_MSG);
984 			break;
985 		}
986 	}
987 done:
988 	free(id);
989 	free(refname);
990 	imsg_free(&imsg);
991 	return err;
992 }
993 
994 const struct got_error *
995 got_privsep_send_packfd(struct imsgbuf *ibuf, int fd)
996 {
997 	return send_fd(ibuf, GOT_IMSG_SEND_PACKFD, fd);
998 }
999 
1000 const struct got_error *
1001 got_privsep_recv_send_progress(int *done, off_t *bytes_sent,
1002     int *success, char **refname, struct imsgbuf *ibuf)
1003 {
1004 	const struct got_error *err = NULL;
1005 	struct imsg imsg;
1006 	size_t datalen;
1007 	struct got_imsg_send_ref_status iref_status;
1008 
1009 	/* Do not reset the current value of 'bytes_sent', it accumulates. */
1010 	*done = 0;
1011 	*success = 0;
1012 	*refname = NULL;
1013 
1014 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1015 	if (err)
1016 		return err;
1017 
1018 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1019 	switch (imsg.hdr.type) {
1020 	case GOT_IMSG_ERROR:
1021 		err = recv_imsg_error(&imsg, datalen);
1022 		break;
1023 	case GOT_IMSG_SEND_UPLOAD_PROGRESS:
1024 		if (datalen < sizeof(*bytes_sent)) {
1025 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1026 			break;
1027 		}
1028 		memcpy(bytes_sent, imsg.data, sizeof(*bytes_sent));
1029 		break;
1030 	case GOT_IMSG_SEND_REF_STATUS:
1031 		if (datalen < sizeof(iref_status)) {
1032 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1033 			break;
1034 		}
1035 		memcpy(&iref_status, imsg.data, sizeof(iref_status));
1036 		if (datalen != sizeof(iref_status) + iref_status.name_len) {
1037 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1038 			break;
1039 		}
1040 		*success = iref_status.success;
1041 		*refname = strndup(imsg.data + sizeof(iref_status),
1042 		    iref_status.name_len);
1043 		break;
1044 	case GOT_IMSG_SEND_DONE:
1045 		if (datalen != 0) {
1046 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1047 			break;
1048 		}
1049 		*done = 1;
1050 		break;
1051 	default:
1052 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1053 		break;
1054 	}
1055 
1056 	imsg_free(&imsg);
1057 	return err;
1058 }
1059 
1060 const struct got_error *
1061 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_sha1,
1062     int fd)
1063 {
1064 	const struct got_error *err = NULL;
1065 
1066 	/* Keep in sync with struct got_imsg_index_pack_request */
1067 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
1068 	    pack_sha1, SHA1_DIGEST_LENGTH) == -1) {
1069 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
1070 		close(fd);
1071 		return err;
1072 	}
1073 	return flush_imsg(ibuf);
1074 }
1075 
1076 const struct got_error *
1077 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
1078 {
1079 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
1080 }
1081 
1082 const struct got_error *
1083 got_privsep_recv_index_progress(int *done, int *nobj_total,
1084     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
1085     struct imsgbuf *ibuf)
1086 {
1087 	const struct got_error *err = NULL;
1088 	struct imsg imsg;
1089 	struct got_imsg_index_pack_progress *iprogress;
1090 	size_t datalen;
1091 
1092 	*done = 0;
1093 	*nobj_total = 0;
1094 	*nobj_indexed = 0;
1095 	*nobj_resolved = 0;
1096 
1097 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1098 	if (err)
1099 		return err;
1100 
1101 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1102 	switch (imsg.hdr.type) {
1103 	case GOT_IMSG_ERROR:
1104 		err = recv_imsg_error(&imsg, datalen);
1105 		break;
1106 	case GOT_IMSG_IDXPACK_PROGRESS:
1107 		if (datalen < sizeof(*iprogress)) {
1108 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1109 			break;
1110 		}
1111 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
1112 		if (iprogress->nobj_total < 0 || iprogress->nobj_indexed < 0 ||
1113 		    iprogress->nobj_loose < 0 || iprogress->nobj_resolved < 0) {
1114 			err = got_error(GOT_ERR_RANGE);
1115 			break;
1116 		}
1117 		*nobj_total = iprogress->nobj_total;
1118 		*nobj_indexed = iprogress->nobj_indexed;
1119 		*nobj_loose = iprogress->nobj_loose;
1120 		*nobj_resolved = iprogress->nobj_resolved;
1121 		break;
1122 	case GOT_IMSG_IDXPACK_DONE:
1123 		if (datalen != 0) {
1124 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1125 			break;
1126 		}
1127 		*done = 1;
1128 		break;
1129 	default:
1130 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1131 		break;
1132 	}
1133 
1134 	imsg_free(&imsg);
1135 	return err;
1136 }
1137 
1138 const struct got_error *
1139 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
1140     struct imsgbuf *ibuf)
1141 {
1142 	struct got_imsg_object *iobj;
1143 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1144 
1145 	if (datalen != sizeof(*iobj))
1146 		return got_error(GOT_ERR_PRIVSEP_LEN);
1147 	iobj = imsg->data;
1148 
1149 	if (iobj->pack_offset < 0)
1150 		return got_error(GOT_ERR_PACK_OFFSET);
1151 
1152 	*obj = calloc(1, sizeof(**obj));
1153 	if (*obj == NULL)
1154 		return got_error_from_errno("calloc");
1155 
1156 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
1157 	(*obj)->type = iobj->type;
1158 	(*obj)->flags = iobj->flags;
1159 	(*obj)->hdrlen = iobj->hdrlen;
1160 	(*obj)->size = iobj->size;
1161 	/* path_packfile is handled by caller */
1162 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
1163 		(*obj)->pack_offset = iobj->pack_offset;
1164 		(*obj)->pack_idx = iobj->pack_idx;
1165 	}
1166 	STAILQ_INIT(&(*obj)->deltas.entries);
1167 	return NULL;
1168 }
1169 
1170 const struct got_error *
1171 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
1172 {
1173 	const struct got_error *err = NULL;
1174 	struct imsg imsg;
1175 	const size_t min_datalen =
1176 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
1177 
1178 	*obj = NULL;
1179 
1180 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1181 	if (err)
1182 		return err;
1183 
1184 	switch (imsg.hdr.type) {
1185 	case GOT_IMSG_OBJECT:
1186 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
1187 		break;
1188 	default:
1189 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1190 		break;
1191 	}
1192 
1193 	imsg_free(&imsg);
1194 
1195 	return err;
1196 }
1197 
1198 static const struct got_error *
1199 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
1200     size_t logmsg_len)
1201 {
1202 	const struct got_error *err = NULL;
1203 	size_t offset, remain;
1204 
1205 	offset = 0;
1206 	remain = logmsg_len;
1207 	while (remain > 0) {
1208 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1209 
1210 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
1211 		    commit->logmsg + offset, n) == -1) {
1212 			err = got_error_from_errno("imsg_compose "
1213 			    "COMMIT_LOGMSG");
1214 			break;
1215 		}
1216 
1217 		err = flush_imsg(ibuf);
1218 		if (err)
1219 			break;
1220 
1221 		offset += n;
1222 		remain -= n;
1223 	}
1224 
1225 	return err;
1226 }
1227 
1228 const struct got_error *
1229 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
1230 {
1231 	const struct got_error *err = NULL;
1232 	struct got_imsg_commit_object *icommit;
1233 	uint8_t *buf;
1234 	size_t len, total;
1235 	struct got_object_qid *qid;
1236 	size_t author_len = strlen(commit->author);
1237 	size_t committer_len = strlen(commit->committer);
1238 	size_t logmsg_len = strlen(commit->logmsg);
1239 
1240 	total = sizeof(*icommit) + author_len + committer_len +
1241 	    commit->nparents * SHA1_DIGEST_LENGTH;
1242 
1243 	buf = malloc(total);
1244 	if (buf == NULL)
1245 		return got_error_from_errno("malloc");
1246 
1247 	icommit = (struct got_imsg_commit_object *)buf;
1248 	memcpy(icommit->tree_id, commit->tree_id->sha1,
1249 	    sizeof(icommit->tree_id));
1250 	icommit->author_len = author_len;
1251 	icommit->author_time = commit->author_time;
1252 	icommit->author_gmtoff = commit->author_gmtoff;
1253 	icommit->committer_len = committer_len;
1254 	icommit->committer_time = commit->committer_time;
1255 	icommit->committer_gmtoff = commit->committer_gmtoff;
1256 	icommit->logmsg_len = logmsg_len;
1257 	icommit->nparents = commit->nparents;
1258 
1259 	len = sizeof(*icommit);
1260 	memcpy(buf + len, commit->author, author_len);
1261 	len += author_len;
1262 	memcpy(buf + len, commit->committer, committer_len);
1263 	len += committer_len;
1264 	STAILQ_FOREACH(qid, &commit->parent_ids, entry) {
1265 		memcpy(buf + len, &qid->id, SHA1_DIGEST_LENGTH);
1266 		len += SHA1_DIGEST_LENGTH;
1267 	}
1268 
1269 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
1270 		err = got_error_from_errno("imsg_compose COMMIT");
1271 		goto done;
1272 	}
1273 
1274 	if (logmsg_len == 0 ||
1275 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1276 		err = flush_imsg(ibuf);
1277 		if (err)
1278 			goto done;
1279 	}
1280 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
1281 done:
1282 	free(buf);
1283 	return err;
1284 }
1285 
1286 static const struct got_error *
1287 get_commit_from_imsg(struct got_commit_object **commit,
1288     struct imsg *imsg, size_t datalen, struct imsgbuf *ibuf)
1289 {
1290 	const struct got_error *err = NULL;
1291 	struct got_imsg_commit_object *icommit;
1292 	size_t len = 0;
1293 	int i;
1294 
1295 	if (datalen < sizeof(*icommit))
1296 		return got_error(GOT_ERR_PRIVSEP_LEN);
1297 
1298 	icommit = imsg->data;
1299 	if (datalen != sizeof(*icommit) + icommit->author_len +
1300 	    icommit->committer_len +
1301 	    icommit->nparents * SHA1_DIGEST_LENGTH)
1302 		return got_error(GOT_ERR_PRIVSEP_LEN);
1303 
1304 	if (icommit->nparents < 0)
1305 		return got_error(GOT_ERR_PRIVSEP_LEN);
1306 
1307 	len += sizeof(*icommit);
1308 
1309 	*commit = got_object_commit_alloc_partial();
1310 	if (*commit == NULL)
1311 		return got_error_from_errno(
1312 		    "got_object_commit_alloc_partial");
1313 
1314 	memcpy((*commit)->tree_id->sha1, icommit->tree_id,
1315 	    SHA1_DIGEST_LENGTH);
1316 	(*commit)->author_time = icommit->author_time;
1317 	(*commit)->author_gmtoff = icommit->author_gmtoff;
1318 	(*commit)->committer_time = icommit->committer_time;
1319 	(*commit)->committer_gmtoff = icommit->committer_gmtoff;
1320 
1321 	(*commit)->author = strndup(imsg->data + len, icommit->author_len);
1322 	if ((*commit)->author == NULL) {
1323 		err = got_error_from_errno("strndup");
1324 		goto done;
1325 	}
1326 	len += icommit->author_len;
1327 
1328 	(*commit)->committer = strndup(imsg->data + len,
1329 	    icommit->committer_len);
1330 	if ((*commit)->committer == NULL) {
1331 		err = got_error_from_errno("strndup");
1332 		goto done;
1333 	}
1334 	len += icommit->committer_len;
1335 
1336 	if (icommit->logmsg_len == 0) {
1337 		(*commit)->logmsg = strdup("");
1338 		if ((*commit)->logmsg == NULL) {
1339 			err = got_error_from_errno("strdup");
1340 			goto done;
1341 		}
1342 	} else {
1343 		size_t offset = 0, remain = icommit->logmsg_len;
1344 
1345 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1346 		if ((*commit)->logmsg == NULL) {
1347 			err = got_error_from_errno("malloc");
1348 			goto done;
1349 		}
1350 		while (remain > 0) {
1351 			struct imsg imsg_log;
1352 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1353 			    remain);
1354 
1355 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1356 			if (err)
1357 				goto done;
1358 
1359 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1360 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1361 				goto done;
1362 			}
1363 
1364 			memcpy((*commit)->logmsg + offset,
1365 			    imsg_log.data, n);
1366 			imsg_free(&imsg_log);
1367 			offset += n;
1368 			remain -= n;
1369 		}
1370 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1371 	}
1372 
1373 	for (i = 0; i < icommit->nparents; i++) {
1374 		struct got_object_qid *qid;
1375 
1376 		err = got_object_qid_alloc_partial(&qid);
1377 		if (err)
1378 			break;
1379 		memcpy(&qid->id, imsg->data + len +
1380 		    i * SHA1_DIGEST_LENGTH, sizeof(qid->id));
1381 		STAILQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1382 		(*commit)->nparents++;
1383 	}
1384 done:
1385 	if (err) {
1386 		got_object_commit_close(*commit);
1387 		*commit = NULL;
1388 	}
1389 	return err;
1390 }
1391 
1392 const struct got_error *
1393 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1394 {
1395 	const struct got_error *err = NULL;
1396 	struct imsg imsg;
1397 	size_t datalen;
1398 	const size_t min_datalen =
1399 	    MIN(sizeof(struct got_imsg_error),
1400 	    sizeof(struct got_imsg_commit_object));
1401 
1402 	*commit = NULL;
1403 
1404 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1405 	if (err)
1406 		return err;
1407 
1408 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1409 
1410 	switch (imsg.hdr.type) {
1411 	case GOT_IMSG_COMMIT:
1412 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1413 		break;
1414 	default:
1415 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1416 		break;
1417 	}
1418 
1419 	imsg_free(&imsg);
1420 
1421 	return err;
1422 }
1423 
1424 static const struct got_error *
1425 send_tree_entries_batch(struct imsgbuf *ibuf,
1426     struct got_parsed_tree_entry *entries, int idx0, int idxN, size_t len)
1427 {
1428 	struct ibuf *wbuf;
1429 	struct got_imsg_tree_entries ientries;
1430 	int i;
1431 
1432 	memset(&ientries, 0, sizeof(ientries));
1433 
1434 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRIES, 0, 0, len);
1435 	if (wbuf == NULL)
1436 		return got_error_from_errno("imsg_create TREE_ENTRY");
1437 
1438 	ientries.nentries = idxN - idx0 + 1;
1439 	if (imsg_add(wbuf, &ientries, sizeof(ientries)) == -1)
1440 		return got_error_from_errno("imsg_add TREE_ENTRY");
1441 
1442 	for (i = idx0; i <= idxN; i++) {
1443 		struct got_parsed_tree_entry *pte = &entries[i];
1444 
1445 		/* Keep in sync with struct got_imsg_tree_object definition! */
1446 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1)
1447 			return got_error_from_errno("imsg_add TREE_ENTRY");
1448 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1)
1449 			return got_error_from_errno("imsg_add TREE_ENTRY");
1450 		if (imsg_add(wbuf, &pte->namelen, sizeof(pte->namelen)) == -1)
1451 			return got_error_from_errno("imsg_add TREE_ENTRY");
1452 
1453 		/* Remaining bytes are the entry's name. */
1454 		if (imsg_add(wbuf, pte->name, pte->namelen) == -1)
1455 			return got_error_from_errno("imsg_add TREE_ENTRY");
1456 	}
1457 
1458 	wbuf->fd = -1;
1459 	imsg_close(ibuf, wbuf);
1460 	return NULL;
1461 }
1462 
1463 static const struct got_error *
1464 send_tree_entries(struct imsgbuf *ibuf, struct got_parsed_tree_entry *entries,
1465     int nentries)
1466 {
1467 	const struct got_error *err = NULL;
1468 	int i, j;
1469 	size_t entries_len = sizeof(struct got_imsg_tree_entries);
1470 
1471 	i = 0;
1472 	for (j = 0; j < nentries; j++) {
1473 		struct got_parsed_tree_entry *pte = &entries[j];
1474 		size_t len = sizeof(*pte) + pte->namelen;
1475 
1476 		if (j > 0 &&
1477 		    entries_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1478 			err = send_tree_entries_batch(ibuf, entries,
1479 			    i, j - 1, entries_len);
1480 			if (err)
1481 				return err;
1482 			i = j;
1483 			entries_len = sizeof(struct got_imsg_tree_entries);
1484 		}
1485 
1486 		entries_len += len;
1487 	}
1488 
1489 	if (j > 0) {
1490 		err = send_tree_entries_batch(ibuf, entries, i, j - 1,
1491 		    entries_len);
1492 		if (err)
1493 			return err;
1494 	}
1495 
1496 	return NULL;
1497 }
1498 
1499 const struct got_error *
1500 got_privsep_send_tree(struct imsgbuf *ibuf,
1501     struct got_parsed_tree_entry *entries, int nentries)
1502 {
1503 	const struct got_error *err = NULL;
1504 	struct got_imsg_tree_object itree;
1505 
1506 	memset(&itree, 0, sizeof(itree));
1507 	itree.nentries = nentries;
1508 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1509 	    == -1)
1510 		return got_error_from_errno("imsg_compose TREE");
1511 
1512 	err = send_tree_entries(ibuf, entries, nentries);
1513 	if (err)
1514 		return err;
1515 
1516 	return flush_imsg(ibuf);
1517 }
1518 
1519 
1520 static const struct got_error *
1521 recv_tree_entries(void *data, size_t datalen, struct got_tree_object *tree,
1522     int *nentries)
1523 {
1524 	const struct got_error *err = NULL;
1525 	struct got_imsg_tree_entries *ientries;
1526 	struct got_tree_entry *te;
1527 	size_t te_offset;
1528 	size_t i;
1529 
1530 	if (datalen <= sizeof(*ientries) ||
1531 	    datalen > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
1532 		return got_error(GOT_ERR_PRIVSEP_LEN);
1533 
1534 	ientries = (struct got_imsg_tree_entries *)data;
1535 	if (ientries->nentries > INT_MAX) {
1536 		return got_error_msg(GOT_ERR_NO_SPACE,
1537 		    "too many tree entries");
1538 	}
1539 
1540 	te_offset = sizeof(*ientries);
1541 	for (i = 0; i < ientries->nentries; i++) {
1542 		struct got_imsg_tree_entry ite;
1543 		const char *te_name;
1544 		uint8_t *buf = (uint8_t *)data + te_offset;
1545 
1546 		if (te_offset >= datalen) {
1547 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1548 			break;
1549 		}
1550 
1551 		/* Might not be aligned, size is ~32 bytes. */
1552 		memcpy(&ite, buf, sizeof(ite));
1553 
1554 		if (ite.namelen >= sizeof(te->name)) {
1555 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1556 			break;
1557 		}
1558 		if (te_offset + sizeof(ite) + ite.namelen > datalen) {
1559 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1560 			break;
1561 		}
1562 
1563 		if (*nentries >= tree->nentries) {
1564 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1565 			break;
1566 		}
1567 		te = &tree->entries[*nentries];
1568 		te_name = buf + sizeof(ite);
1569 		memcpy(te->name, te_name, ite.namelen);
1570 		te->name[ite.namelen] = '\0';
1571 		memcpy(te->id.sha1, ite.id, SHA1_DIGEST_LENGTH);
1572 		te->mode = ite.mode;
1573 		te->idx = *nentries;
1574 		(*nentries)++;
1575 
1576 		te_offset += sizeof(ite) + ite.namelen;
1577 	}
1578 
1579 	return err;
1580 }
1581 
1582 const struct got_error *
1583 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1584 {
1585 	const struct got_error *err = NULL;
1586 	const size_t min_datalen =
1587 	    MIN(sizeof(struct got_imsg_error),
1588 	    sizeof(struct got_imsg_tree_object));
1589 	struct got_imsg_tree_object *itree;
1590 	int nentries = 0;
1591 
1592 	*tree = NULL;
1593 
1594 	err = read_imsg(ibuf);
1595 	if (err)
1596 		goto done;
1597 
1598 	for (;;) {
1599 		struct imsg imsg;
1600 		size_t n;
1601 		size_t datalen;
1602 
1603 		n = imsg_get(ibuf, &imsg);
1604 		if (n == 0) {
1605 			if ((*tree)) {
1606 				if (nentries < (*tree)->nentries) {
1607 					err = read_imsg(ibuf);
1608 					if (err)
1609 						break;
1610 					continue;
1611 				} else
1612 					break;
1613 			} else {
1614 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1615 				break;
1616 			}
1617 		}
1618 
1619 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen) {
1620 			imsg_free(&imsg);
1621 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1622 			break;
1623 		}
1624 
1625 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1626 
1627 		switch (imsg.hdr.type) {
1628 		case GOT_IMSG_ERROR:
1629 			err = recv_imsg_error(&imsg, datalen);
1630 			break;
1631 		case GOT_IMSG_TREE:
1632 			/* This message should only appear once. */
1633 			if (*tree != NULL) {
1634 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1635 				break;
1636 			}
1637 			if (datalen != sizeof(*itree)) {
1638 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1639 				break;
1640 			}
1641 			itree = imsg.data;
1642 			if (itree->nentries < 0) {
1643 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1644 				break;
1645 			}
1646 			*tree = malloc(sizeof(**tree));
1647 			if (*tree == NULL) {
1648 				err = got_error_from_errno("malloc");
1649 				break;
1650 			}
1651 			(*tree)->entries = calloc(itree->nentries,
1652 			    sizeof(struct got_tree_entry));
1653 			if ((*tree)->entries == NULL) {
1654 				err = got_error_from_errno("malloc");
1655 				free(*tree);
1656 				*tree = NULL;
1657 				break;
1658 			}
1659 			(*tree)->nentries = itree->nentries;
1660 			(*tree)->refcnt = 0;
1661 			break;
1662 		case GOT_IMSG_TREE_ENTRIES:
1663 			/* This message should be preceeded by GOT_IMSG_TREE. */
1664 			if (*tree == NULL) {
1665 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1666 				break;
1667 			}
1668 			err = recv_tree_entries(imsg.data, datalen,
1669 			    *tree, &nentries);
1670 			break;
1671 		default:
1672 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1673 			break;
1674 		}
1675 
1676 		imsg_free(&imsg);
1677 		if (err)
1678 			break;
1679 	}
1680 done:
1681 	if (*tree && (*tree)->nentries != nentries) {
1682 		if (err == NULL)
1683 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1684 		got_object_tree_close(*tree);
1685 		*tree = NULL;
1686 	}
1687 
1688 	return err;
1689 }
1690 
1691 const struct got_error *
1692 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1693     const uint8_t *data)
1694 {
1695 	struct got_imsg_blob iblob;
1696 
1697 	memset(&iblob, 0, sizeof(iblob));
1698 	iblob.size = size;
1699 	iblob.hdrlen = hdrlen;
1700 
1701 	if (data) {
1702 		uint8_t *buf;
1703 
1704 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1705 			return got_error(GOT_ERR_NO_SPACE);
1706 
1707 		buf = malloc(sizeof(iblob) + size);
1708 		if (buf == NULL)
1709 			return got_error_from_errno("malloc");
1710 
1711 		memcpy(buf, &iblob, sizeof(iblob));
1712 		memcpy(buf + sizeof(iblob), data, size);
1713 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1714 		    sizeof(iblob) + size) == -1) {
1715 			free(buf);
1716 			return got_error_from_errno("imsg_compose BLOB");
1717 		}
1718 		free(buf);
1719 	} else {
1720 		/* Data has already been written to file descriptor. */
1721 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1722 		    sizeof(iblob)) == -1)
1723 			return got_error_from_errno("imsg_compose BLOB");
1724 	}
1725 
1726 
1727 	return flush_imsg(ibuf);
1728 }
1729 
1730 const struct got_error *
1731 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1732     struct imsgbuf *ibuf)
1733 {
1734 	const struct got_error *err = NULL;
1735 	struct imsg imsg;
1736 	struct got_imsg_blob *iblob;
1737 	size_t datalen;
1738 
1739 	*outbuf = NULL;
1740 
1741 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1742 	if (err)
1743 		return err;
1744 
1745 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1746 
1747 	switch (imsg.hdr.type) {
1748 	case GOT_IMSG_BLOB:
1749 		if (datalen < sizeof(*iblob)) {
1750 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1751 			break;
1752 		}
1753 		iblob = imsg.data;
1754 		*size = iblob->size;
1755 		*hdrlen = iblob->hdrlen;
1756 
1757 		if (datalen == sizeof(*iblob)) {
1758 			/* Data has been written to file descriptor. */
1759 			break;
1760 		}
1761 
1762 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX ||
1763 		    *size > datalen + sizeof(*iblob)) {
1764 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1765 			break;
1766 		}
1767 
1768 		*outbuf = malloc(*size);
1769 		if (*outbuf == NULL) {
1770 			err = got_error_from_errno("malloc");
1771 			break;
1772 		}
1773 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1774 		break;
1775 	default:
1776 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1777 		break;
1778 	}
1779 
1780 	imsg_free(&imsg);
1781 
1782 	return err;
1783 }
1784 
1785 static const struct got_error *
1786 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1787 {
1788 	const struct got_error *err = NULL;
1789 	size_t offset, remain;
1790 
1791 	offset = 0;
1792 	remain = tagmsg_len;
1793 	while (remain > 0) {
1794 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1795 
1796 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1797 		    tag->tagmsg + offset, n) == -1) {
1798 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1799 			break;
1800 		}
1801 
1802 		err = flush_imsg(ibuf);
1803 		if (err)
1804 			break;
1805 
1806 		offset += n;
1807 		remain -= n;
1808 	}
1809 
1810 	return err;
1811 }
1812 
1813 const struct got_error *
1814 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1815 {
1816 	const struct got_error *err = NULL;
1817 	struct got_imsg_tag_object *itag;
1818 	uint8_t *buf;
1819 	size_t len, total;
1820 	size_t tag_len = strlen(tag->tag);
1821 	size_t tagger_len = strlen(tag->tagger);
1822 	size_t tagmsg_len = strlen(tag->tagmsg);
1823 
1824 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1825 
1826 	buf = malloc(total);
1827 	if (buf == NULL)
1828 		return got_error_from_errno("malloc");
1829 
1830 	itag = (struct got_imsg_tag_object *)buf;
1831 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1832 	itag->obj_type = tag->obj_type;
1833 	itag->tag_len = tag_len;
1834 	itag->tagger_len = tagger_len;
1835 	itag->tagger_time = tag->tagger_time;
1836 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1837 	itag->tagmsg_len = tagmsg_len;
1838 
1839 	len = sizeof(*itag);
1840 	memcpy(buf + len, tag->tag, tag_len);
1841 	len += tag_len;
1842 	memcpy(buf + len, tag->tagger, tagger_len);
1843 	len += tagger_len;
1844 
1845 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1846 		err = got_error_from_errno("imsg_compose TAG");
1847 		goto done;
1848 	}
1849 
1850 	if (tagmsg_len == 0 ||
1851 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1852 		err = flush_imsg(ibuf);
1853 		if (err)
1854 			goto done;
1855 	}
1856 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1857 done:
1858 	free(buf);
1859 	return err;
1860 }
1861 
1862 const struct got_error *
1863 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1864 {
1865 	const struct got_error *err = NULL;
1866 	struct imsg imsg;
1867 	struct got_imsg_tag_object *itag;
1868 	size_t len, datalen;
1869 	const size_t min_datalen =
1870 	    MIN(sizeof(struct got_imsg_error),
1871 	    sizeof(struct got_imsg_tag_object));
1872 
1873 	*tag = NULL;
1874 
1875 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1876 	if (err)
1877 		return err;
1878 
1879 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1880 	len = 0;
1881 
1882 	switch (imsg.hdr.type) {
1883 	case GOT_IMSG_TAG:
1884 		if (datalen < sizeof(*itag)) {
1885 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1886 			break;
1887 		}
1888 		itag = imsg.data;
1889 		if (datalen != sizeof(*itag) + itag->tag_len +
1890 		    itag->tagger_len) {
1891 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1892 			break;
1893 		}
1894 		len += sizeof(*itag);
1895 
1896 		*tag = calloc(1, sizeof(**tag));
1897 		if (*tag == NULL) {
1898 			err = got_error_from_errno("calloc");
1899 			break;
1900 		}
1901 
1902 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1903 
1904 		(*tag)->tag = strndup(imsg.data + len, itag->tag_len);
1905 		if ((*tag)->tag == NULL) {
1906 			err = got_error_from_errno("strndup");
1907 			break;
1908 		}
1909 		len += itag->tag_len;
1910 
1911 		(*tag)->obj_type = itag->obj_type;
1912 		(*tag)->tagger_time = itag->tagger_time;
1913 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1914 
1915 		(*tag)->tagger = strndup(imsg.data + len, itag->tagger_len);
1916 		if ((*tag)->tagger == NULL) {
1917 			err = got_error_from_errno("strndup");
1918 			break;
1919 		}
1920 		len += itag->tagger_len;
1921 
1922 		if (itag->tagmsg_len == 0) {
1923 			(*tag)->tagmsg = strdup("");
1924 			if ((*tag)->tagmsg == NULL) {
1925 				err = got_error_from_errno("strdup");
1926 				break;
1927 			}
1928 		} else {
1929 			size_t offset = 0, remain = itag->tagmsg_len;
1930 
1931 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1932 			if ((*tag)->tagmsg == NULL) {
1933 				err = got_error_from_errno("malloc");
1934 				break;
1935 			}
1936 			while (remain > 0) {
1937 				struct imsg imsg_log;
1938 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1939 				    remain);
1940 
1941 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1942 				if (err)
1943 					return err;
1944 
1945 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1946 					return got_error(GOT_ERR_PRIVSEP_MSG);
1947 
1948 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1949 				    n);
1950 				imsg_free(&imsg_log);
1951 				offset += n;
1952 				remain -= n;
1953 			}
1954 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1955 		}
1956 
1957 		break;
1958 	default:
1959 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1960 		break;
1961 	}
1962 
1963 	imsg_free(&imsg);
1964 
1965 	return err;
1966 }
1967 
1968 const struct got_error *
1969 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1970     struct got_packidx *packidx)
1971 {
1972 	const struct got_error *err = NULL;
1973 	struct got_imsg_packidx ipackidx;
1974 	struct got_imsg_pack ipack;
1975 	int fd;
1976 
1977 	memset(&ipackidx, 0, sizeof(ipackidx));
1978 	memset(&ipack, 0, sizeof(ipack));
1979 
1980 	ipackidx.len = packidx->len;
1981 	ipackidx.packfile_size = pack->filesize;
1982 	fd = dup(packidx->fd);
1983 	if (fd == -1)
1984 		return got_error_from_errno("dup");
1985 
1986 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
1987 	    sizeof(ipackidx)) == -1) {
1988 		err = got_error_from_errno("imsg_compose PACKIDX");
1989 		close(fd);
1990 		return err;
1991 	}
1992 
1993 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
1994 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
1995 		return got_error(GOT_ERR_NO_SPACE);
1996 	ipack.filesize = pack->filesize;
1997 
1998 	fd = dup(pack->fd);
1999 	if (fd == -1)
2000 		return got_error_from_errno("dup");
2001 
2002 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
2003 	    == -1) {
2004 		err = got_error_from_errno("imsg_compose PACK");
2005 		close(fd);
2006 		return err;
2007 	}
2008 
2009 	return flush_imsg(ibuf);
2010 }
2011 
2012 const struct got_error *
2013 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
2014     struct got_object_id *id)
2015 {
2016 	struct got_imsg_packed_object iobj;
2017 
2018 	memset(&iobj, 0, sizeof(iobj));
2019 	iobj.idx = idx;
2020 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2021 
2022 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
2023 	    &iobj, sizeof(iobj)) == -1)
2024 		return got_error_from_errno("imsg_compose "
2025 		    "PACKED_OBJECT_REQUEST");
2026 
2027 	return flush_imsg(ibuf);
2028 }
2029 
2030 const struct got_error *
2031 got_privsep_send_packed_raw_obj_req(struct imsgbuf *ibuf, int idx,
2032     struct got_object_id *id)
2033 {
2034 	struct got_imsg_packed_object iobj;
2035 
2036 	memset(&iobj, 0, sizeof(iobj));
2037 	iobj.idx = idx;
2038 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2039 
2040 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_RAW_OBJECT_REQUEST, 0, 0, -1,
2041 	    &iobj, sizeof(iobj)) == -1)
2042 		return got_error_from_errno("imsg_compose "
2043 		    "PACKED_OBJECT_REQUEST");
2044 
2045 	return flush_imsg(ibuf);
2046 }
2047 
2048 const struct got_error *
2049 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
2050 {
2051 	const struct got_error *err = NULL;
2052 
2053 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
2054 	    NULL, 0) == -1) {
2055 		err = got_error_from_errno("imsg_compose "
2056 		    "GITCONFIG_PARSE_REQUEST");
2057 		close(fd);
2058 		return err;
2059 	}
2060 
2061 	return flush_imsg(ibuf);
2062 }
2063 
2064 const struct got_error *
2065 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
2066 {
2067 	if (imsg_compose(ibuf,
2068 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
2069 	    NULL, 0) == -1)
2070 		return got_error_from_errno("imsg_compose "
2071 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
2072 
2073 	return flush_imsg(ibuf);
2074 }
2075 
2076 const struct got_error *
2077 got_privsep_send_gitconfig_repository_extensions_req(struct imsgbuf *ibuf)
2078 {
2079 	if (imsg_compose(ibuf,
2080 	    GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST, 0, 0, -1,
2081 	    NULL, 0) == -1)
2082 		return got_error_from_errno("imsg_compose "
2083 		    "GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST");
2084 
2085 	return flush_imsg(ibuf);
2086 }
2087 
2088 
2089 const struct got_error *
2090 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
2091 {
2092 	if (imsg_compose(ibuf,
2093 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
2094 		return got_error_from_errno("imsg_compose "
2095 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
2096 
2097 	return flush_imsg(ibuf);
2098 }
2099 
2100 const struct got_error *
2101 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
2102 {
2103 	if (imsg_compose(ibuf,
2104 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
2105 		return got_error_from_errno("imsg_compose "
2106 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
2107 
2108 	return flush_imsg(ibuf);
2109 }
2110 
2111 const struct got_error *
2112 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
2113 {
2114 	if (imsg_compose(ibuf,
2115 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2116 		return got_error_from_errno("imsg_compose "
2117 		    "GITCONFIG_REMOTE_REQUEST");
2118 
2119 	return flush_imsg(ibuf);
2120 }
2121 
2122 const struct got_error *
2123 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
2124 {
2125 	if (imsg_compose(ibuf,
2126 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
2127 		return got_error_from_errno("imsg_compose "
2128 		    "GITCONFIG_OWNER_REQUEST");
2129 
2130 	return flush_imsg(ibuf);
2131 }
2132 
2133 const struct got_error *
2134 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
2135 {
2136 	const struct got_error *err = NULL;
2137 	struct imsg imsg;
2138 	size_t datalen;
2139 
2140 	*str = NULL;
2141 
2142 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2143 	if (err)
2144 		return err;
2145 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2146 
2147 	switch (imsg.hdr.type) {
2148 	case GOT_IMSG_GITCONFIG_STR_VAL:
2149 		if (datalen == 0)
2150 			break;
2151 		/* datalen does not include terminating \0 */
2152 		*str = malloc(datalen + 1);
2153 		if (*str == NULL) {
2154 			err = got_error_from_errno("malloc");
2155 			break;
2156 		}
2157 		memcpy(*str, imsg.data, datalen);
2158 		(*str)[datalen] = '\0';
2159 		break;
2160 	default:
2161 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2162 		break;
2163 	}
2164 
2165 	imsg_free(&imsg);
2166 	return err;
2167 }
2168 
2169 const struct got_error *
2170 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
2171 {
2172 	const struct got_error *err = NULL;
2173 	struct imsg imsg;
2174 	size_t datalen;
2175 	const size_t min_datalen =
2176 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
2177 
2178 	*val = 0;
2179 
2180 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2181 	if (err)
2182 		return err;
2183 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2184 
2185 	switch (imsg.hdr.type) {
2186 	case GOT_IMSG_GITCONFIG_INT_VAL:
2187 		if (datalen != sizeof(*val)) {
2188 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2189 			break;
2190 		}
2191 		memcpy(val, imsg.data, sizeof(*val));
2192 		break;
2193 	default:
2194 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2195 		break;
2196 	}
2197 
2198 	imsg_free(&imsg);
2199 	return err;
2200 }
2201 
2202 static void
2203 free_remote_data(struct got_remote_repo *remote)
2204 {
2205 	int i;
2206 
2207 	free(remote->name);
2208 	free(remote->fetch_url);
2209 	free(remote->send_url);
2210 	for (i = 0; i < remote->nfetch_branches; i++)
2211 		free(remote->fetch_branches[i]);
2212 	free(remote->fetch_branches);
2213 	for (i = 0; i < remote->nsend_branches; i++)
2214 		free(remote->send_branches[i]);
2215 	free(remote->send_branches);
2216 	for (i = 0; i < remote->nfetch_refs; i++)
2217 		free(remote->fetch_refs[i]);
2218 	free(remote->fetch_refs);
2219 }
2220 
2221 const struct got_error *
2222 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
2223     int *nremotes, struct imsgbuf *ibuf)
2224 {
2225 	const struct got_error *err = NULL;
2226 	struct imsg imsg;
2227 	size_t datalen;
2228 	struct got_imsg_remotes iremotes;
2229 	struct got_imsg_remote iremote;
2230 
2231 	*remotes = NULL;
2232 	*nremotes = 0;
2233 	iremotes.nremotes = 0;
2234 
2235 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
2236 	if (err)
2237 		return err;
2238 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2239 
2240 	switch (imsg.hdr.type) {
2241 	case GOT_IMSG_GITCONFIG_REMOTES:
2242 		if (datalen != sizeof(iremotes)) {
2243 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2244 			break;
2245 		}
2246 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2247 		if (iremotes.nremotes == 0) {
2248 			imsg_free(&imsg);
2249 			return NULL;
2250 		}
2251 		break;
2252 	default:
2253 		imsg_free(&imsg);
2254 		return got_error(GOT_ERR_PRIVSEP_MSG);
2255 	}
2256 
2257 	imsg_free(&imsg);
2258 
2259 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2260 	if (*remotes == NULL)
2261 		return got_error_from_errno("recallocarray");
2262 
2263 	while (*nremotes < iremotes.nremotes) {
2264 		struct got_remote_repo *remote;
2265 
2266 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
2267 		if (err)
2268 			break;
2269 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2270 
2271 		switch (imsg.hdr.type) {
2272 		case GOT_IMSG_GITCONFIG_REMOTE:
2273 			remote = &(*remotes)[*nremotes];
2274 			memset(remote, 0, sizeof(*remote));
2275 			if (datalen < sizeof(iremote)) {
2276 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2277 				break;
2278 			}
2279 			memcpy(&iremote, imsg.data, sizeof(iremote));
2280 			if (iremote.name_len == 0 ||
2281 			    iremote.fetch_url_len == 0 ||
2282 			    iremote.send_url_len == 0 ||
2283 			    (sizeof(iremote) + iremote.name_len +
2284 			    iremote.fetch_url_len + iremote.send_url_len) > datalen) {
2285 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2286 				break;
2287 			}
2288 			remote->name = strndup(imsg.data + sizeof(iremote),
2289 			    iremote.name_len);
2290 			if (remote->name == NULL) {
2291 				err = got_error_from_errno("strndup");
2292 				break;
2293 			}
2294 			remote->fetch_url = strndup(imsg.data + sizeof(iremote) +
2295 			    iremote.name_len, iremote.fetch_url_len);
2296 			if (remote->fetch_url == NULL) {
2297 				err = got_error_from_errno("strndup");
2298 				free_remote_data(remote);
2299 				break;
2300 			}
2301 			remote->send_url = strndup(imsg.data + sizeof(iremote) +
2302 			    iremote.name_len + iremote.fetch_url_len,
2303 			    iremote.send_url_len);
2304 			if (remote->send_url == NULL) {
2305 				err = got_error_from_errno("strndup");
2306 				free_remote_data(remote);
2307 				break;
2308 			}
2309 			remote->mirror_references = iremote.mirror_references;
2310 			remote->fetch_all_branches = iremote.fetch_all_branches;
2311 			remote->nfetch_branches = 0;
2312 			remote->fetch_branches = NULL;
2313 			remote->nsend_branches = 0;
2314 			remote->send_branches = NULL;
2315 			remote->nfetch_refs = 0;
2316 			remote->fetch_refs = NULL;
2317 			(*nremotes)++;
2318 			break;
2319 		default:
2320 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2321 			break;
2322 		}
2323 
2324 		imsg_free(&imsg);
2325 		if (err)
2326 			break;
2327 	}
2328 
2329 	if (err) {
2330 		int i;
2331 		for (i = 0; i < *nremotes; i++)
2332 			free_remote_data(&(*remotes)[i]);
2333 		free(*remotes);
2334 		*remotes = NULL;
2335 		*nremotes = 0;
2336 	}
2337 	return err;
2338 }
2339 
2340 const struct got_error *
2341 got_privsep_send_gotconfig_parse_req(struct imsgbuf *ibuf, int fd)
2342 {
2343 	const struct got_error *err = NULL;
2344 
2345 	if (imsg_compose(ibuf, GOT_IMSG_GOTCONFIG_PARSE_REQUEST, 0, 0, fd,
2346 	    NULL, 0) == -1) {
2347 		err = got_error_from_errno("imsg_compose "
2348 		    "GOTCONFIG_PARSE_REQUEST");
2349 		close(fd);
2350 		return err;
2351 	}
2352 
2353 	return flush_imsg(ibuf);
2354 }
2355 
2356 const struct got_error *
2357 got_privsep_send_gotconfig_author_req(struct imsgbuf *ibuf)
2358 {
2359 	if (imsg_compose(ibuf,
2360 	    GOT_IMSG_GOTCONFIG_AUTHOR_REQUEST, 0, 0, -1, NULL, 0) == -1)
2361 		return got_error_from_errno("imsg_compose "
2362 		    "GOTCONFIG_AUTHOR_REQUEST");
2363 
2364 	return flush_imsg(ibuf);
2365 }
2366 
2367 const struct got_error *
2368 got_privsep_send_gotconfig_remotes_req(struct imsgbuf *ibuf)
2369 {
2370 	if (imsg_compose(ibuf,
2371 	    GOT_IMSG_GOTCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2372 		return got_error_from_errno("imsg_compose "
2373 		    "GOTCONFIG_REMOTE_REQUEST");
2374 
2375 	return flush_imsg(ibuf);
2376 }
2377 
2378 const struct got_error *
2379 got_privsep_recv_gotconfig_str(char **str, struct imsgbuf *ibuf)
2380 {
2381 	const struct got_error *err = NULL;
2382 	struct imsg imsg;
2383 	size_t datalen;
2384 
2385 	*str = NULL;
2386 
2387 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2388 	if (err)
2389 		return err;
2390 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2391 
2392 	switch (imsg.hdr.type) {
2393 	case GOT_IMSG_ERROR:
2394 		err = recv_imsg_error(&imsg, datalen);
2395 		break;
2396 	case GOT_IMSG_GOTCONFIG_STR_VAL:
2397 		if (datalen == 0)
2398 			break;
2399 		/* datalen does not include terminating \0 */
2400 		*str = malloc(datalen + 1);
2401 		if (*str == NULL) {
2402 			err = got_error_from_errno("malloc");
2403 			break;
2404 		}
2405 		memcpy(*str, imsg.data, datalen);
2406 		(*str)[datalen] = '\0';
2407 		break;
2408 	default:
2409 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2410 		break;
2411 	}
2412 
2413 	imsg_free(&imsg);
2414 	return err;
2415 }
2416 
2417 const struct got_error *
2418 got_privsep_recv_gotconfig_remotes(struct got_remote_repo **remotes,
2419     int *nremotes, struct imsgbuf *ibuf)
2420 {
2421 	const struct got_error *err = NULL;
2422 	struct imsg imsg;
2423 	size_t datalen;
2424 	struct got_imsg_remotes iremotes;
2425 	struct got_imsg_remote iremote;
2426 	const size_t min_datalen =
2427 	    MIN(sizeof(struct got_imsg_error), sizeof(iremotes));
2428 
2429 	*remotes = NULL;
2430 	*nremotes = 0;
2431 	iremotes.nremotes = 0;
2432 
2433 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2434 	if (err)
2435 		return err;
2436 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2437 
2438 	switch (imsg.hdr.type) {
2439 	case GOT_IMSG_ERROR:
2440 		err = recv_imsg_error(&imsg, datalen);
2441 		break;
2442 	case GOT_IMSG_GOTCONFIG_REMOTES:
2443 		if (datalen != sizeof(iremotes)) {
2444 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2445 			break;
2446 		}
2447 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2448 		if (iremotes.nremotes < 0) {
2449 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2450 			break;
2451 		}
2452 		if (iremotes.nremotes == 0) {
2453 			imsg_free(&imsg);
2454 			return NULL;
2455 		}
2456 		break;
2457 	default:
2458 		imsg_free(&imsg);
2459 		return got_error(GOT_ERR_PRIVSEP_MSG);
2460 	}
2461 
2462 	imsg_free(&imsg);
2463 
2464 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2465 	if (*remotes == NULL)
2466 		return got_error_from_errno("recallocarray");
2467 
2468 	while (*nremotes < iremotes.nremotes) {
2469 		struct got_remote_repo *remote;
2470 		const size_t min_datalen =
2471 		    MIN(sizeof(struct got_imsg_error), sizeof(iremote));
2472 		int i;
2473 
2474 		err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2475 		if (err)
2476 			break;
2477 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2478 
2479 		switch (imsg.hdr.type) {
2480 		case GOT_IMSG_ERROR:
2481 			err = recv_imsg_error(&imsg, datalen);
2482 			break;
2483 		case GOT_IMSG_GOTCONFIG_REMOTE:
2484 			remote = &(*remotes)[*nremotes];
2485 			memset(remote, 0, sizeof(*remote));
2486 			if (datalen < sizeof(iremote)) {
2487 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2488 				break;
2489 			}
2490 			memcpy(&iremote, imsg.data, sizeof(iremote));
2491 			if (iremote.name_len == 0 ||
2492 			    (iremote.fetch_url_len == 0 &&
2493 			    iremote.send_url_len == 0) ||
2494 			    (sizeof(iremote) + iremote.name_len +
2495 			    iremote.fetch_url_len + iremote.send_url_len) >
2496 			    datalen) {
2497 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2498 				break;
2499 			}
2500 			remote->name = strndup(imsg.data + sizeof(iremote),
2501 			    iremote.name_len);
2502 			if (remote->name == NULL) {
2503 				err = got_error_from_errno("strndup");
2504 				break;
2505 			}
2506 			remote->fetch_url = strndup(imsg.data +
2507 			    sizeof(iremote) + iremote.name_len,
2508 			    iremote.fetch_url_len);
2509 			if (remote->fetch_url == NULL) {
2510 				err = got_error_from_errno("strndup");
2511 				free_remote_data(remote);
2512 				break;
2513 			}
2514 			remote->send_url = strndup(imsg.data +
2515 			    sizeof(iremote) + iremote.name_len +
2516 			    iremote.fetch_url_len, iremote.send_url_len);
2517 			if (remote->send_url == NULL) {
2518 				err = got_error_from_errno("strndup");
2519 				free_remote_data(remote);
2520 				break;
2521 			}
2522 			remote->mirror_references = iremote.mirror_references;
2523 			remote->fetch_all_branches = iremote.fetch_all_branches;
2524 			if (iremote.nfetch_branches > 0) {
2525 				remote->fetch_branches = recallocarray(NULL, 0,
2526 				    iremote.nfetch_branches, sizeof(char *));
2527 				if (remote->fetch_branches == NULL) {
2528 					err = got_error_from_errno("calloc");
2529 					free_remote_data(remote);
2530 					break;
2531 				}
2532 			}
2533 			remote->nfetch_branches = 0;
2534 			for (i = 0; i < iremote.nfetch_branches; i++) {
2535 				char *branch;
2536 				err = got_privsep_recv_gotconfig_str(&branch,
2537 				    ibuf);
2538 				if (err) {
2539 					free_remote_data(remote);
2540 					goto done;
2541 				}
2542 				remote->fetch_branches[i] = branch;
2543 				remote->nfetch_branches++;
2544 			}
2545 			if (iremote.nsend_branches > 0) {
2546 				remote->send_branches = recallocarray(NULL, 0,
2547 				    iremote.nsend_branches, sizeof(char *));
2548 				if (remote->send_branches == NULL) {
2549 					err = got_error_from_errno("calloc");
2550 					free_remote_data(remote);
2551 					break;
2552 				}
2553 			}
2554 			remote->nsend_branches = 0;
2555 			for (i = 0; i < iremote.nsend_branches; i++) {
2556 				char *branch;
2557 				err = got_privsep_recv_gotconfig_str(&branch,
2558 				    ibuf);
2559 				if (err) {
2560 					free_remote_data(remote);
2561 					goto done;
2562 				}
2563 				remote->send_branches[i] = branch;
2564 				remote->nsend_branches++;
2565 			}
2566 			if (iremote.nfetch_refs > 0) {
2567 				remote->fetch_refs = recallocarray(NULL, 0,
2568 				    iremote.nfetch_refs, sizeof(char *));
2569 				if (remote->fetch_refs == NULL) {
2570 					err = got_error_from_errno("calloc");
2571 					free_remote_data(remote);
2572 					break;
2573 				}
2574 			}
2575 			remote->nfetch_refs = 0;
2576 			for (i = 0; i < iremote.nfetch_refs; i++) {
2577 				char *ref;
2578 				err = got_privsep_recv_gotconfig_str(&ref,
2579 				    ibuf);
2580 				if (err) {
2581 					free_remote_data(remote);
2582 					goto done;
2583 				}
2584 				remote->fetch_refs[i] = ref;
2585 				remote->nfetch_refs++;
2586 			}
2587 			(*nremotes)++;
2588 			break;
2589 		default:
2590 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2591 			break;
2592 		}
2593 
2594 		imsg_free(&imsg);
2595 		if (err)
2596 			break;
2597 	}
2598 done:
2599 	if (err) {
2600 		int i;
2601 		for (i = 0; i < *nremotes; i++)
2602 			free_remote_data(&(*remotes)[i]);
2603 		free(*remotes);
2604 		*remotes = NULL;
2605 		*nremotes = 0;
2606 	}
2607 	return err;
2608 }
2609 
2610 const struct got_error *
2611 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
2612     struct got_object_id *id, int idx, const char *path)
2613 {
2614 	struct ibuf *wbuf;
2615 	size_t path_len = strlen(path) + 1;
2616 
2617 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
2618 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
2619 	if (wbuf == NULL)
2620 		return got_error_from_errno(
2621 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
2622 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1)
2623 		return got_error_from_errno("imsg_add "
2624 		    "COMMIT_TRAVERSAL_REQUEST");
2625 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1)
2626 		return got_error_from_errno("imsg_add "
2627 		    "COMMIT_TRAVERSAL_REQUEST");
2628 	if (imsg_add(wbuf, path, path_len) == -1)
2629 		return got_error_from_errno("imsg_add "
2630 		    "COMMIT_TRAVERSAL_REQUEST");
2631 
2632 	wbuf->fd = -1;
2633 	imsg_close(ibuf, wbuf);
2634 
2635 	return flush_imsg(ibuf);
2636 }
2637 
2638 const struct got_error *
2639 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
2640     struct got_object_id **changed_commit_id,
2641     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
2642 {
2643 	const struct got_error *err = NULL;
2644 	struct imsg imsg;
2645 	struct got_imsg_traversed_commits *icommits;
2646 	size_t datalen;
2647 	int i, done = 0;
2648 
2649 	*changed_commit = NULL;
2650 	*changed_commit_id = NULL;
2651 
2652 	while (!done) {
2653 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2654 		if (err)
2655 			return err;
2656 
2657 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2658 		switch (imsg.hdr.type) {
2659 		case GOT_IMSG_TRAVERSED_COMMITS:
2660 			icommits = imsg.data;
2661 			if (datalen != sizeof(*icommits) +
2662 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
2663 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2664 				break;
2665 			}
2666 			for (i = 0; i < icommits->ncommits; i++) {
2667 				struct got_object_qid *qid;
2668 				uint8_t *sha1 = (uint8_t *)imsg.data +
2669 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
2670 				err = got_object_qid_alloc_partial(&qid);
2671 				if (err)
2672 					break;
2673 				memcpy(qid->id.sha1, sha1, SHA1_DIGEST_LENGTH);
2674 				STAILQ_INSERT_TAIL(commit_ids, qid, entry);
2675 
2676 				/* The last commit may contain a change. */
2677 				if (i == icommits->ncommits - 1) {
2678 					*changed_commit_id =
2679 					    got_object_id_dup(&qid->id);
2680 					if (*changed_commit_id == NULL) {
2681 						err = got_error_from_errno(
2682 						    "got_object_id_dup");
2683 						break;
2684 					}
2685 				}
2686 			}
2687 			break;
2688 		case GOT_IMSG_COMMIT:
2689 			if (*changed_commit_id == NULL) {
2690 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2691 				break;
2692 			}
2693 			err = get_commit_from_imsg(changed_commit, &imsg,
2694 			    datalen, ibuf);
2695 			break;
2696 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
2697 			done = 1;
2698 			break;
2699 		default:
2700 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2701 			break;
2702 		}
2703 
2704 		imsg_free(&imsg);
2705 		if (err)
2706 			break;
2707 	}
2708 
2709 	if (err)
2710 		got_object_id_queue_free(commit_ids);
2711 	return err;
2712 }
2713 
2714 const struct got_error *
2715 got_privsep_send_enumerated_tree(size_t *totlen, struct imsgbuf *ibuf,
2716     struct got_object_id *tree_id, const char *path,
2717     struct got_parsed_tree_entry *entries, int nentries)
2718 {
2719 	const struct got_error *err = NULL;
2720 	struct ibuf *wbuf;
2721 	size_t path_len = strlen(path);
2722 	size_t msglen;
2723 
2724 	msglen = sizeof(struct got_imsg_enumerated_tree) + path_len;
2725 	wbuf = imsg_create(ibuf, GOT_IMSG_ENUMERATED_TREE, 0, 0, msglen);
2726 	if (wbuf == NULL)
2727 		return got_error_from_errno("imsg_create ENUMERATED_TREE");
2728 
2729 	if (imsg_add(wbuf, tree_id->sha1, SHA1_DIGEST_LENGTH) == -1)
2730 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2731 	if (imsg_add(wbuf, &nentries, sizeof(nentries)) == -1)
2732 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2733 	if (imsg_add(wbuf, path, path_len) == -1)
2734 		return got_error_from_errno("imsg_add ENUMERATED_TREE");
2735 
2736 	wbuf->fd = -1;
2737 	imsg_close(ibuf, wbuf);
2738 
2739 	if (entries) {
2740 		err = send_tree_entries(ibuf, entries, nentries);
2741 		if (err)
2742 			return err;
2743 	}
2744 
2745 	return flush_imsg(ibuf);
2746 }
2747 
2748 const struct got_error *
2749 got_privsep_send_object_enumeration_request(struct imsgbuf *ibuf)
2750 {
2751 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_REQUEST,
2752 	    0, 0, -1, NULL, 0) == -1)
2753 		return got_error_from_errno("imsg_compose "
2754 		    "OBJECT_ENUMERATION_REQUEST");
2755 
2756 	return flush_imsg(ibuf);
2757 }
2758 
2759 const struct got_error *
2760 got_privsep_send_object_enumeration_done(struct imsgbuf *ibuf)
2761 {
2762 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_DONE,
2763 	    0, 0, -1, NULL, 0) == -1)
2764 		return got_error_from_errno("imsg_compose "
2765 		    "OBJECT_ENUMERATION_DONE");
2766 
2767 	return flush_imsg(ibuf);
2768 }
2769 
2770 const struct got_error *
2771 got_privsep_send_object_enumeration_incomplete(struct imsgbuf *ibuf)
2772 {
2773 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_ENUMERATION_INCOMPLETE,
2774 	    0, 0, -1, NULL, 0) == -1)
2775 		return got_error_from_errno("imsg_compose "
2776 		    "OBJECT_ENUMERATION_INCOMPLETE");
2777 
2778 	return flush_imsg(ibuf);
2779 }
2780 
2781 const struct got_error *
2782 got_privsep_send_enumerated_commit(struct imsgbuf *ibuf,
2783     struct got_object_id *id, time_t mtime)
2784 {
2785 	struct ibuf *wbuf;
2786 
2787 	wbuf = imsg_create(ibuf, GOT_IMSG_ENUMERATED_COMMIT, 0, 0,
2788 	    sizeof(struct got_imsg_enumerated_commit) + SHA1_DIGEST_LENGTH);
2789 	if (wbuf == NULL)
2790 		return got_error_from_errno("imsg_create ENUMERATED_COMMIT");
2791 
2792 	/* Keep in sync with struct got_imsg_enumerated_commit! */
2793 	if (imsg_add(wbuf, id, SHA1_DIGEST_LENGTH) == -1)
2794 		return got_error_from_errno("imsg_add ENUMERATED_COMMIT");
2795 	if (imsg_add(wbuf, &mtime, sizeof(mtime)) == -1)
2796 		return got_error_from_errno("imsg_add ENUMERATED_COMMIT");
2797 
2798 	wbuf->fd = -1;
2799 	imsg_close(ibuf, wbuf);
2800 	/* Don't flush yet, tree entries or ENUMERATION_DONE will follow. */
2801 	return NULL;
2802 }
2803 
2804 const struct got_error *
2805 got_privsep_recv_enumerated_objects(int *found_all_objects,
2806     struct imsgbuf *ibuf,
2807     got_object_enumerate_commit_cb cb_commit,
2808     got_object_enumerate_tree_cb cb_tree, void *cb_arg,
2809     struct got_repository *repo)
2810 {
2811 	const struct got_error *err = NULL;
2812 	struct imsg imsg;
2813 	struct got_imsg_enumerated_commit *icommit = NULL;
2814 	struct got_object_id commit_id;
2815 	int have_commit = 0;
2816 	time_t mtime = 0;
2817 	struct got_tree_object tree;
2818 	struct got_imsg_enumerated_tree *itree;
2819 	struct got_object_id tree_id;
2820 	char *path = NULL, *canon_path = NULL;
2821 	size_t datalen, path_len;
2822 	int nentries = -1;
2823 	int done = 0;
2824 
2825 	*found_all_objects = 0;
2826 	memset(&tree, 0, sizeof(tree));
2827 
2828 	while (!done) {
2829 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2830 		if (err)
2831 			break;
2832 
2833 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2834 		switch (imsg.hdr.type) {
2835 		case GOT_IMSG_ENUMERATED_COMMIT:
2836 			if (have_commit && nentries != -1) {
2837 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2838 				break;
2839 			}
2840 			if (datalen != sizeof(*icommit)) {
2841 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2842 				break;
2843 			}
2844 			icommit = (struct got_imsg_enumerated_commit *)imsg.data;
2845 			memcpy(commit_id.sha1, icommit->id, SHA1_DIGEST_LENGTH);
2846 			mtime = icommit->mtime;
2847 			have_commit = 1;
2848 			break;
2849 		case GOT_IMSG_ENUMERATED_TREE:
2850 			/* Should be preceeded by GOT_IMSG_ENUMERATED_COMMIT. */
2851 			if (!have_commit) {
2852 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2853 				break;
2854 			}
2855 			if (datalen < sizeof(*itree)) {
2856 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2857 				break;
2858 			}
2859 			itree = imsg.data;
2860 			path_len = datalen - sizeof(*itree);
2861 			if (path_len == 0) {
2862 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2863 				break;
2864 			}
2865 			memcpy(tree_id.sha1, itree->id, sizeof(tree_id.sha1));
2866 			free(path);
2867 			path = malloc(path_len + 1);
2868 			if (path == NULL) {
2869 				err = got_error_from_errno("malloc");
2870 				break;
2871 			}
2872 			free(canon_path);
2873 			canon_path = malloc(path_len + 1);
2874 			if (canon_path == NULL) {
2875 				err = got_error_from_errno("malloc");
2876 				break;
2877 			}
2878 			memcpy(path, (uint8_t *)imsg.data + sizeof(*itree),
2879 			    path_len);
2880 			path[path_len] = '\0';
2881 			if (!got_path_is_absolute(path)) {
2882 				err = got_error(GOT_ERR_BAD_PATH);
2883 				break;
2884 			}
2885 			if (got_path_is_root_dir(path)) {
2886 				/* XXX check what got_canonpath() does wrong */
2887 				canon_path[0] = '/';
2888 				canon_path[1] = '\0';
2889 			} else {
2890 				err = got_canonpath(path, canon_path,
2891 				    path_len + 1);
2892 				if (err)
2893 					break;
2894 			}
2895 			if (strcmp(path, canon_path) != 0) {
2896 				err = got_error(GOT_ERR_BAD_PATH);
2897 				break;
2898 			}
2899 			if (nentries != -1) {
2900 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2901 				break;
2902 			}
2903 			if (itree->nentries < -1) {
2904 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2905 				break;
2906 			}
2907 			if (itree->nentries == -1) {
2908 				/* Tree was not found in pack file. */
2909 				err = cb_tree(cb_arg, NULL, mtime, &tree_id,
2910 				    path, repo);
2911 				break;
2912 			}
2913 			if (itree->nentries > INT_MAX) {
2914 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2915 				break;
2916 			}
2917 			tree.entries = calloc(itree->nentries,
2918 			    sizeof(struct got_tree_entry));
2919 			if (tree.entries == NULL) {
2920 				err = got_error_from_errno("calloc");
2921 				break;
2922 			}
2923 			if (itree->nentries == 0) {
2924 				err = cb_tree(cb_arg, &tree, mtime, &tree_id,
2925 				    path, repo);
2926 				if (err)
2927 					break;
2928 
2929 				/* Prepare for next tree. */
2930 				free(tree.entries);
2931 				memset(&tree, 0, sizeof(tree));
2932 				nentries = -1;
2933 			} else {
2934 				tree.nentries = itree->nentries;
2935 				nentries = 0;
2936 			}
2937 			break;
2938 		case GOT_IMSG_TREE_ENTRIES:
2939 			/* Should be preceeded by GOT_IMSG_ENUMERATED_TREE. */
2940 			if (nentries <= -1) {
2941 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2942 				break;
2943 			}
2944 			err = recv_tree_entries(imsg.data, datalen,
2945 			    &tree, &nentries);
2946 			if (err)
2947 				break;
2948 			if (tree.nentries == nentries) {
2949 				err = cb_tree(cb_arg, &tree, mtime, &tree_id,
2950 				    path, repo);
2951 				if (err)
2952 					break;
2953 
2954 				/* Prepare for next tree. */
2955 				free(tree.entries);
2956 				memset(&tree, 0, sizeof(tree));
2957 				nentries = -1;
2958 			}
2959 			break;
2960 		case GOT_IMSG_TREE_ENUMERATION_DONE:
2961 			/* All trees have been found and traversed. */
2962 			if (!have_commit || path == NULL || nentries != -1) {
2963 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2964 				break;
2965 			}
2966 			err = cb_commit(cb_arg, mtime, &commit_id, repo);
2967 			if (err)
2968 				break;
2969 			have_commit = 0;
2970 			break;
2971 		case GOT_IMSG_OBJECT_ENUMERATION_DONE:
2972 			*found_all_objects = 1;
2973 			done = 1;
2974 			break;
2975 		case GOT_IMSG_OBJECT_ENUMERATION_INCOMPLETE:
2976 			done = 1;
2977 			break;
2978 		default:
2979 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2980 			break;
2981 		}
2982 
2983 		imsg_free(&imsg);
2984 		if (err)
2985 			break;
2986 	}
2987 
2988 	free(path);
2989 	free(canon_path);
2990 	free(tree.entries);
2991 	return err;
2992 }
2993 
2994 const struct got_error *
2995 got_privsep_send_raw_delta_req(struct imsgbuf *ibuf, int idx,
2996     struct got_object_id *id)
2997 {
2998 	struct got_imsg_raw_delta_request dreq;
2999 
3000 	memset(&dreq, 0, sizeof(dreq));
3001 	dreq.idx = idx;
3002 	memcpy(dreq.id, id->sha1, SHA1_DIGEST_LENGTH);
3003 
3004 	if (imsg_compose(ibuf, GOT_IMSG_RAW_DELTA_REQUEST, 0, 0, -1,
3005 	    &dreq, sizeof(dreq)) == -1)
3006 		return got_error_from_errno("imsg_compose RAW_DELTA_REQUEST");
3007 
3008 	return flush_imsg(ibuf);
3009 }
3010 
3011 const struct got_error *
3012 got_privsep_send_raw_delta_outfd(struct imsgbuf *ibuf, int fd)
3013 {
3014 	return send_fd(ibuf, GOT_IMSG_RAW_DELTA_OUTFD, fd);
3015 }
3016 
3017 const struct got_error *
3018 got_privsep_send_raw_delta(struct imsgbuf *ibuf, uint64_t base_size,
3019     uint64_t result_size,  off_t delta_size, off_t delta_compressed_size,
3020     off_t delta_offset, off_t delta_out_offset, struct got_object_id *base_id)
3021 {
3022 	struct got_imsg_raw_delta idelta;
3023 	int ret;
3024 
3025 	memset(&idelta, 0, sizeof(idelta));
3026 	idelta.base_size = base_size;
3027 	idelta.result_size = result_size;
3028 	idelta.delta_size = delta_size;
3029 	idelta.delta_compressed_size = delta_compressed_size;
3030 	idelta.delta_offset = delta_offset;
3031 	idelta.delta_out_offset = delta_out_offset;
3032 	memcpy(idelta.base_id, base_id->sha1, SHA1_DIGEST_LENGTH);
3033 
3034 	ret = imsg_compose(ibuf, GOT_IMSG_RAW_DELTA, 0, 0, -1,
3035 	    &idelta, sizeof(idelta));
3036 	if (ret == -1)
3037 		return got_error_from_errno("imsg_compose RAW_DELTA");
3038 
3039 	return flush_imsg(ibuf);
3040 }
3041 
3042 const struct got_error *
3043 got_privsep_recv_raw_delta(uint64_t *base_size, uint64_t *result_size,
3044     off_t *delta_size, off_t *delta_compressed_size, off_t *delta_offset,
3045     off_t *delta_out_offset, struct got_object_id **base_id, struct imsgbuf *ibuf)
3046 {
3047 	const struct got_error *err = NULL;
3048 	struct imsg imsg;
3049 	struct got_imsg_raw_delta *delta;
3050 	size_t datalen;
3051 
3052 	*base_size = 0;
3053 	*result_size = 0;
3054 	*delta_size = 0;
3055 	*delta_compressed_size = 0;
3056 	*delta_offset = 0;
3057 	*delta_out_offset = 0;
3058 	*base_id = NULL;
3059 
3060 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3061 	if (err)
3062 		return err;
3063 
3064 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3065 
3066 	switch (imsg.hdr.type) {
3067 	case GOT_IMSG_RAW_DELTA:
3068 		if (datalen != sizeof(*delta)) {
3069 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3070 			break;
3071 		}
3072 		delta = imsg.data;
3073 		*base_size = delta->base_size;
3074 		*result_size = delta->result_size;
3075 		*delta_size = delta->delta_size;
3076 		*delta_compressed_size = delta->delta_compressed_size;
3077 		*delta_offset = delta->delta_offset;
3078 		*delta_out_offset = delta->delta_out_offset;
3079 		*base_id = calloc(1, sizeof(**base_id));
3080 		if (*base_id == NULL) {
3081 			err = got_error_from_errno("malloc");
3082 			break;
3083 		}
3084 		memcpy((*base_id)->sha1, delta->base_id, SHA1_DIGEST_LENGTH);
3085 		break;
3086 	default:
3087 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3088 		break;
3089 	}
3090 
3091 	imsg_free(&imsg);
3092 
3093 	if (err) {
3094 		free(*base_id);
3095 		*base_id = NULL;
3096 	}
3097 	return err;
3098 }
3099 
3100 static const struct got_error *
3101 send_idlist(struct imsgbuf *ibuf, struct got_object_id **ids, size_t nids)
3102 {
3103 	const struct got_error *err = NULL;
3104 	struct got_imsg_object_idlist idlist;
3105 	struct ibuf *wbuf;
3106 	size_t i;
3107 
3108 	memset(&idlist, 0, sizeof(idlist));
3109 
3110 	if (nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS)
3111 		return got_error(GOT_ERR_NO_SPACE);
3112 
3113 	wbuf = imsg_create(ibuf, GOT_IMSG_OBJ_ID_LIST, 0, 0,
3114 	    sizeof(idlist) + nids * sizeof(**ids));
3115 	if (wbuf == NULL) {
3116 		err = got_error_from_errno("imsg_create OBJ_ID_LIST");
3117 		return err;
3118 	}
3119 
3120 	idlist.nids = nids;
3121 	if (imsg_add(wbuf, &idlist, sizeof(idlist)) == -1)
3122 		return got_error_from_errno("imsg_add OBJ_ID_LIST");
3123 
3124 	for (i = 0; i < nids; i++) {
3125 		struct got_object_id *id = ids[i];
3126 		if (imsg_add(wbuf, id, sizeof(*id)) == -1)
3127 			return got_error_from_errno("imsg_add OBJ_ID_LIST");
3128 	}
3129 
3130 	wbuf->fd = -1;
3131 	imsg_close(ibuf, wbuf);
3132 
3133 	return flush_imsg(ibuf);
3134 }
3135 
3136 const struct got_error *
3137 got_privsep_send_object_idlist(struct imsgbuf *ibuf,
3138     struct got_object_id **ids, size_t nids)
3139 {
3140 	const struct got_error *err = NULL;
3141 	struct got_object_id *idlist[GOT_IMSG_OBJ_ID_LIST_MAX_NIDS];
3142 	int i, queued = 0;
3143 
3144 	for (i = 0; i < nids; i++) {
3145 		idlist[i % nitems(idlist)] = ids[i];
3146 		queued++;
3147 		if (queued >= nitems(idlist)) {
3148 			err = send_idlist(ibuf, idlist, queued);
3149 			if (err)
3150 				return err;
3151 			queued = 0;
3152 		}
3153 	}
3154 
3155 	if (queued > 0) {
3156 		err = send_idlist(ibuf, idlist, queued);
3157 		if (err)
3158 			return err;
3159 	}
3160 
3161 	return NULL;
3162 }
3163 
3164 const struct got_error *
3165 got_privsep_send_object_idlist_done(struct imsgbuf *ibuf)
3166 {
3167 	if (imsg_compose(ibuf, GOT_IMSG_OBJ_ID_LIST_DONE, 0, 0, -1, NULL, 0)
3168 	    == -1)
3169 		return got_error_from_errno("imsg_compose OBJ_ID_LIST_DONE");
3170 
3171 	return flush_imsg(ibuf);
3172 }
3173 
3174 const struct got_error *
3175 got_privsep_recv_object_idlist(int *done, struct got_object_id **ids,
3176     size_t *nids, struct imsgbuf *ibuf)
3177 {
3178 	const struct got_error *err = NULL;
3179 	struct imsg imsg;
3180 	struct got_imsg_object_idlist *idlist;
3181 	size_t datalen;
3182 
3183 	*ids = NULL;
3184 	*done = 0;
3185 	*nids = 0;
3186 
3187 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3188 	if (err)
3189 		return err;
3190 
3191 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3192 	switch (imsg.hdr.type) {
3193 	case GOT_IMSG_OBJ_ID_LIST:
3194 		if (datalen < sizeof(*idlist)) {
3195 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3196 			break;
3197 		}
3198 		idlist = imsg.data;
3199 		if (idlist->nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS ||
3200 		    idlist->nids * sizeof(**ids) > datalen - sizeof(*idlist)) {
3201 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3202 			break;
3203 		}
3204 		*nids = idlist->nids;
3205 		*ids = calloc(*nids, sizeof(**ids));
3206 		if (*ids == NULL) {
3207 			err = got_error_from_errno("calloc");
3208 			break;
3209 		}
3210 		memcpy(*ids, (uint8_t *)imsg.data + sizeof(*idlist),
3211 		    *nids * sizeof(**ids));
3212 		break;
3213 	case GOT_IMSG_OBJ_ID_LIST_DONE:
3214 		*done = 1;
3215 		break;
3216 	default:
3217 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3218 		break;
3219 	}
3220 
3221 	imsg_free(&imsg);
3222 
3223 	return err;
3224 }
3225 
3226 const struct got_error *
3227 got_privsep_send_delta_reuse_req(struct imsgbuf *ibuf)
3228 {
3229 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_REQUEST, 0, 0, -1, NULL, 0)
3230 	    == -1)
3231 		return got_error_from_errno("imsg_compose DELTA_REUSE_REQUEST");
3232 
3233 	return flush_imsg(ibuf);
3234 }
3235 
3236 const struct got_error *
3237 got_privsep_send_reused_deltas(struct imsgbuf *ibuf,
3238     struct got_imsg_reused_delta *deltas, size_t ndeltas)
3239 {
3240 	const struct got_error *err = NULL;
3241 	struct ibuf *wbuf;
3242 	struct got_imsg_reused_deltas ideltas;
3243 	size_t i;
3244 
3245 	memset(&ideltas, 0, sizeof(ideltas));
3246 
3247 	if (ndeltas > GOT_IMSG_REUSED_DELTAS_MAX_NDELTAS)
3248 		return got_error(GOT_ERR_NO_SPACE);
3249 
3250 	wbuf = imsg_create(ibuf, GOT_IMSG_REUSED_DELTAS, 0, 0,
3251 	    sizeof(ideltas) + ndeltas * sizeof(*deltas));
3252 	if (wbuf == NULL) {
3253 		err = got_error_from_errno("imsg_create REUSED_DELTAS");
3254 		return err;
3255 	}
3256 
3257 	ideltas.ndeltas = ndeltas;
3258 	if (imsg_add(wbuf, &ideltas, sizeof(ideltas)) == -1)
3259 		return got_error_from_errno("imsg_add REUSED_DELTAS");
3260 
3261 	for (i = 0; i < ndeltas; i++) {
3262 		struct got_imsg_reused_delta *delta = &deltas[i];
3263 		if (imsg_add(wbuf, delta, sizeof(*delta)) == -1)
3264 			return got_error_from_errno("imsg_add REUSED_DELTAS");
3265 	}
3266 
3267 	wbuf->fd = -1;
3268 	imsg_close(ibuf, wbuf);
3269 
3270 	return flush_imsg(ibuf);
3271 }
3272 
3273 const struct got_error *
3274 got_privsep_send_reused_deltas_done(struct imsgbuf *ibuf)
3275 {
3276 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_DONE, 0, 0, -1, NULL, 0)
3277 	    == -1)
3278 		return got_error_from_errno("imsg_compose DELTA_REUSE_DONE");
3279 
3280 	return flush_imsg(ibuf);
3281 }
3282 
3283 const struct got_error *
3284 got_privsep_recv_reused_deltas(int *done, struct got_imsg_reused_delta *deltas,
3285     size_t *ndeltas, struct imsgbuf *ibuf)
3286 {
3287 	const struct got_error *err = NULL;
3288 	struct imsg imsg;
3289 	struct got_imsg_reused_deltas *ideltas;
3290 	size_t datalen;
3291 
3292 	*done = 0;
3293 	*ndeltas = 0;
3294 
3295 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3296 	if (err)
3297 		return err;
3298 
3299 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3300 	switch (imsg.hdr.type) {
3301 	case GOT_IMSG_REUSED_DELTAS:
3302 		if (datalen < sizeof(*ideltas)) {
3303 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3304 			break;
3305 		}
3306 		ideltas = imsg.data;
3307 		if (ideltas->ndeltas > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS ||
3308 		    ideltas->ndeltas * sizeof(*deltas) >
3309 		    datalen - sizeof(*ideltas)) {
3310 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3311 			break;
3312 		}
3313 		*ndeltas = ideltas->ndeltas;
3314 		memcpy(deltas, (uint8_t *)imsg.data + sizeof(*ideltas),
3315 		    *ndeltas * sizeof(*deltas));
3316 		break;
3317 	case GOT_IMSG_DELTA_REUSE_DONE:
3318 		*done = 1;
3319 		break;
3320 	default:
3321 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3322 		break;
3323 	}
3324 
3325 	imsg_free(&imsg);
3326 
3327 	return err;
3328 }
3329 
3330 const struct got_error *
3331 got_privsep_init_commit_painting(struct imsgbuf *ibuf)
3332 {
3333 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_PAINTING_INIT,
3334 	    0, 0, -1, NULL, 0)
3335 	    == -1)
3336 		return got_error_from_errno("imsg_compose "
3337 		    "COMMIT_PAINTING_INIT");
3338 
3339 	return flush_imsg(ibuf);
3340 }
3341 
3342 const struct got_error *
3343 got_privsep_send_painting_request(struct imsgbuf *ibuf, int idx,
3344     struct got_object_id *id, intptr_t color)
3345 {
3346 	struct got_imsg_commit_painting_request ireq;
3347 
3348 	memset(&ireq, 0, sizeof(ireq));
3349 	memcpy(ireq.id, id->sha1, sizeof(ireq.id));
3350 	ireq.idx = idx;
3351 	ireq.color = color;
3352 
3353 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_PAINTING_REQUEST, 0, 0, -1,
3354 	    &ireq, sizeof(ireq)) == -1)
3355 		return got_error_from_errno("imsg_compose "
3356 		    "COMMIT_PAINTING_REQUEST");
3357 
3358 	return flush_imsg(ibuf);
3359 }
3360 
3361 static const struct got_error *
3362 send_painted_commits(struct got_object_id_queue *ids, int *nids,
3363     size_t remain, int present_in_pack, struct imsgbuf *ibuf)
3364 {
3365 	const struct got_error *err = NULL;
3366 	struct ibuf *wbuf = NULL;
3367 	struct got_object_qid *qid;
3368 	size_t msglen;
3369 	int ncommits;
3370 	intptr_t color;
3371 
3372 	msglen = MIN(remain, MAX_IMSGSIZE - IMSG_HEADER_SIZE);
3373 	ncommits = (msglen - sizeof(struct got_imsg_painted_commits)) /
3374 	    sizeof(struct got_imsg_painted_commit);
3375 
3376 	wbuf = imsg_create(ibuf, GOT_IMSG_PAINTED_COMMITS, 0, 0, msglen);
3377 	if (wbuf == NULL) {
3378 		err = got_error_from_errno("imsg_create PAINTED_COMMITS");
3379 		return err;
3380 	}
3381 
3382 	/* Keep in sync with struct got_imsg_painted_commits! */
3383 	if (imsg_add(wbuf, &ncommits, sizeof(ncommits)) == -1)
3384 		return got_error_from_errno("imsg_add PAINTED_COMMITS");
3385 	if (imsg_add(wbuf, &present_in_pack, sizeof(present_in_pack)) == -1)
3386 		return got_error_from_errno("imsg_add PAINTED_COMMITS");
3387 
3388 	while (ncommits > 0) {
3389 		qid = STAILQ_FIRST(ids);
3390 		STAILQ_REMOVE_HEAD(ids, entry);
3391 		ncommits--;
3392 		(*nids)--;
3393 		color = (intptr_t)qid->data;
3394 
3395 		/* Keep in sync with struct got_imsg_painted_commit! */
3396 		if (imsg_add(wbuf, qid->id.sha1, SHA1_DIGEST_LENGTH) == -1)
3397 			return got_error_from_errno("imsg_add PAINTED_COMMITS");
3398 		if (imsg_add(wbuf, &color, sizeof(color)) == -1)
3399 			return got_error_from_errno("imsg_add PAINTED_COMMITS");
3400 
3401 		got_object_qid_free(qid);
3402 	}
3403 
3404 	wbuf->fd = -1;
3405 	imsg_close(ibuf, wbuf);
3406 
3407 	return flush_imsg(ibuf);
3408 }
3409 
3410 const struct got_error *
3411 got_privsep_send_painted_commits(struct imsgbuf *ibuf,
3412     struct got_object_id_queue *ids, int *nids,
3413     int present_in_pack, int flush)
3414 {
3415 	const struct got_error *err;
3416 	size_t remain;
3417 
3418 	if (*nids <= 0)
3419 		return NULL;
3420 
3421 	do {
3422 		remain = (sizeof(struct got_imsg_painted_commits)) +
3423 		    *nids * sizeof(struct got_imsg_painted_commit);
3424 		if (flush || remain >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
3425 			err = send_painted_commits(ids, nids, remain,
3426 			    present_in_pack, ibuf);
3427 			if (err)
3428 				return err;
3429 		}
3430 	} while (flush && *nids > 0);
3431 
3432 	return NULL;
3433 }
3434 
3435 const struct got_error *
3436 got_privsep_send_painting_commits_done(struct imsgbuf *ibuf)
3437 {
3438 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_PAINTING_DONE,
3439 	    0, 0, -1, NULL, 0)
3440 	    == -1)
3441 		return got_error_from_errno("imsg_compose "
3442 		    "COMMIT_PAINTING_DONE");
3443 
3444 	return flush_imsg(ibuf);
3445 }
3446 
3447 const struct got_error *
3448 got_privsep_recv_painted_commits(struct got_object_id_queue *new_ids,
3449     got_privsep_recv_painted_commit_cb cb, void *cb_arg, struct imsgbuf *ibuf)
3450 {
3451 	const struct got_error *err = NULL;
3452 	struct imsg imsg;
3453 	struct got_imsg_painted_commits icommits;
3454 	struct got_imsg_painted_commit icommit;
3455 	size_t datalen;
3456 	int i;
3457 
3458 	for (;;) {
3459 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3460 		if (err)
3461 			return err;
3462 
3463 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3464 		if (imsg.hdr.type == GOT_IMSG_COMMIT_PAINTING_DONE)
3465 			break;
3466 		if (imsg.hdr.type != GOT_IMSG_PAINTED_COMMITS)
3467 			return got_error(GOT_ERR_PRIVSEP_MSG);
3468 
3469 		if (datalen < sizeof(icommits))
3470 			return got_error(GOT_ERR_PRIVSEP_LEN);
3471 		memcpy(&icommits, imsg.data, sizeof(icommits));
3472 		if (icommits.ncommits * sizeof(icommit) < icommits.ncommits ||
3473 		    datalen < sizeof(icommits) +
3474 		    icommits.ncommits * sizeof(icommit))
3475 			return got_error(GOT_ERR_PRIVSEP_LEN);
3476 
3477 		for (i = 0; i < icommits.ncommits; i++) {
3478 			memcpy(&icommit,
3479 			    (uint8_t *)imsg.data + sizeof(icommits) + i * sizeof(icommit),
3480 			    sizeof(icommit));
3481 
3482 			if (icommits.present_in_pack) {
3483 				struct got_object_id id;
3484 				memcpy(id.sha1, icommit.id, SHA1_DIGEST_LENGTH);
3485 				err = cb(cb_arg, &id, icommit.color);
3486 				if (err)
3487 					break;
3488 			} else {
3489 				struct got_object_qid *qid;
3490 				err = got_object_qid_alloc_partial(&qid);
3491 				if (err)
3492 					break;
3493 				memcpy(qid->id.sha1, icommit.id,
3494 				    SHA1_DIGEST_LENGTH);
3495 				qid->data = (void *)icommit.color;
3496 				STAILQ_INSERT_TAIL(new_ids, qid, entry);
3497 			}
3498 		}
3499 
3500 		imsg_free(&imsg);
3501 	}
3502 
3503 	return err;
3504 }
3505 
3506 const struct got_error *
3507 got_privsep_unveil_exec_helpers(void)
3508 {
3509 	const char *helpers[] = {
3510 	    GOT_PATH_PROG_READ_PACK,
3511 	    GOT_PATH_PROG_READ_OBJECT,
3512 	    GOT_PATH_PROG_READ_COMMIT,
3513 	    GOT_PATH_PROG_READ_TREE,
3514 	    GOT_PATH_PROG_READ_BLOB,
3515 	    GOT_PATH_PROG_READ_TAG,
3516 	    GOT_PATH_PROG_READ_GITCONFIG,
3517 	    GOT_PATH_PROG_READ_GOTCONFIG,
3518 	    GOT_PATH_PROG_READ_PATCH,
3519 	    GOT_PATH_PROG_FETCH_PACK,
3520 	    GOT_PATH_PROG_INDEX_PACK,
3521 	    GOT_PATH_PROG_SEND_PACK,
3522 	};
3523 	size_t i;
3524 
3525 	for (i = 0; i < nitems(helpers); i++) {
3526 		if (unveil(helpers[i], "x") == 0)
3527 			continue;
3528 		return got_error_from_errno2("unveil", helpers[i]);
3529 	}
3530 
3531 	return NULL;
3532 }
3533 
3534 void
3535 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
3536 {
3537 	if (close(imsg_fds[0]) == -1) {
3538 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3539 		_exit(1);
3540 	}
3541 
3542 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
3543 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3544 		_exit(1);
3545 	}
3546 
3547 	closefrom(GOT_IMSG_FD_CHILD + 1);
3548 
3549 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
3550 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
3551 		    strerror(errno));
3552 		_exit(1);
3553 	}
3554 }