1 /*
2  * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
3  * Copyright (c) 2020 Ori Bernstein <ori@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/types.h>
19 #include <sys/uio.h>
20 #include <sys/wait.h>
21 
22 #include <ctype.h>
23 #include <limits.h>
24 #include <signal.h>
25 #include <stdio.h>
26 #include <stdlib.h>
27 #include <string.h>
28 #include <errno.h>
29 #include <stdint.h>
30 #include <poll.h>
31 #include <unistd.h>
32 #include <zlib.h>
33 #include <time.h>
34 
35 #include "got_compat.h"
36 
37 #include "got_object.h"
38 #include "got_error.h"
39 #include "got_path.h"
40 #include "got_repository.h"
41 
42 #include "got_lib_sha1.h"
43 #include "got_lib_delta.h"
44 #include "got_lib_inflate.h"
45 #include "got_lib_object.h"
46 #include "got_lib_object_parse.h"
47 #include "got_lib_privsep.h"
48 #include "got_lib_pack.h"
49 
50 #ifndef MIN
51 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
52 #endif
53 
54 #ifndef nitems
55 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
56 #endif
57 
58 static const struct got_error *
59 poll_fd(int fd, int events, int timeout)
60 {
61 	struct pollfd pfd[1];
62 	struct timespec ts;
63 	sigset_t sigset;
64 	int n;
65 
66 	pfd[0].fd = fd;
67 	pfd[0].events = events;
68 
69 	ts.tv_sec = timeout;
70 	ts.tv_nsec = 0;
71 
72 	if (sigemptyset(&sigset) == -1)
73 		return got_error_from_errno("sigemptyset");
74 	if (sigaddset(&sigset, SIGWINCH) == -1)
75 		return got_error_from_errno("sigaddset");
76 
77 	n = ppoll(pfd, 1, timeout == INFTIM ? NULL : &ts, &sigset);
78 	if (n == -1)
79 		return got_error_from_errno("ppoll");
80 	if (n == 0)
81 		return got_error(GOT_ERR_TIMEOUT);
82 	if (pfd[0].revents & (POLLERR | POLLNVAL))
83 		return got_error_from_errno("poll error");
84 	if (pfd[0].revents & (events | POLLHUP))
85 		return NULL;
86 
87 	return got_error(GOT_ERR_INTERRUPT);
88 }
89 
90 static const struct got_error *
91 read_imsg(struct imsgbuf *ibuf)
92 {
93 	const struct got_error *err;
94 	size_t n;
95 
96 	err = poll_fd(ibuf->fd, POLLIN, INFTIM);
97 	if (err)
98 		return err;
99 
100 	n = imsg_read(ibuf);
101 	if (n == -1) {
102 		if (errno == EAGAIN) /* Could be a file-descriptor leak. */
103 			return got_error(GOT_ERR_PRIVSEP_NO_FD);
104 		return got_error(GOT_ERR_PRIVSEP_READ);
105 	}
106 	if (n == 0)
107 		return got_error(GOT_ERR_PRIVSEP_PIPE);
108 
109 	return NULL;
110 }
111 
112 const struct got_error *
113 got_privsep_wait_for_child(pid_t pid)
114 {
115 	int child_status;
116 
117 	if (waitpid(pid, &child_status, 0) == -1)
118 		return got_error_from_errno("waitpid");
119 
120 	if (!WIFEXITED(child_status))
121 		return got_error(GOT_ERR_PRIVSEP_DIED);
122 
123 	if (WEXITSTATUS(child_status) != 0)
124 		return got_error(GOT_ERR_PRIVSEP_EXIT);
125 
126 	return NULL;
127 }
128 
129 static const struct got_error *
130 recv_imsg_error(struct imsg *imsg, size_t datalen)
131 {
132 	struct got_imsg_error *ierr;
133 
134 	if (datalen != sizeof(*ierr))
135 		return got_error(GOT_ERR_PRIVSEP_LEN);
136 
137 	ierr = imsg->data;
138 	if (ierr->code == GOT_ERR_ERRNO) {
139 		static struct got_error serr;
140 		serr.code = GOT_ERR_ERRNO;
141 		serr.msg = strerror(ierr->errno_code);
142 		return &serr;
143 	}
144 
145 	return got_error(ierr->code);
146 }
147 
148 const struct got_error *
149 got_privsep_recv_imsg(struct imsg *imsg, struct imsgbuf *ibuf,
150     size_t min_datalen)
151 {
152 	const struct got_error *err;
153 	ssize_t n;
154 
155 	n = imsg_get(ibuf, imsg);
156 	if (n == -1)
157 		return got_error_from_errno("imsg_get");
158 
159 	while (n == 0) {
160 		err = read_imsg(ibuf);
161 		if (err)
162 			return err;
163 		n = imsg_get(ibuf, imsg);
164 		if (n == -1)
165 			return got_error_from_errno("imsg_get");
166 	}
167 
168 	if (imsg->hdr.len < IMSG_HEADER_SIZE + min_datalen)
169 		return got_error(GOT_ERR_PRIVSEP_LEN);
170 
171 	if (imsg->hdr.type == GOT_IMSG_ERROR) {
172 		size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
173 		return recv_imsg_error(imsg, datalen);
174 	}
175 
176 	return NULL;
177 }
178 
179 /* Attempt to send an error in an imsg. Complain on stderr as a last resort. */
180 void
181 got_privsep_send_error(struct imsgbuf *ibuf, const struct got_error *err)
182 {
183 	const struct got_error *poll_err;
184 	struct got_imsg_error ierr;
185 	int ret;
186 
187 	ierr.code = err->code;
188 	if (err->code == GOT_ERR_ERRNO)
189 		ierr.errno_code = errno;
190 	else
191 		ierr.errno_code = 0;
192 	ret = imsg_compose(ibuf, GOT_IMSG_ERROR, 0, 0, -1, &ierr, sizeof(ierr));
193 	if (ret == -1) {
194 		fprintf(stderr, "%s: error %d \"%s\": imsg_compose: %s\n",
195 		    getprogname(), err->code, err->msg, strerror(errno));
196 		return;
197 	}
198 
199 	poll_err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
200 	if (poll_err) {
201 		fprintf(stderr, "%s: error %d \"%s\": poll: %s\n",
202 		    getprogname(), err->code, err->msg, poll_err->msg);
203 		return;
204 	}
205 
206 	ret = imsg_flush(ibuf);
207 	if (ret == -1) {
208 		fprintf(stderr, "%s: error %d \"%s\": imsg_flush: %s\n",
209 		    getprogname(), err->code, err->msg, strerror(errno));
210 		imsg_clear(ibuf);
211 		return;
212 	}
213 }
214 
215 static const struct got_error *
216 flush_imsg(struct imsgbuf *ibuf)
217 {
218 	const struct got_error *err;
219 
220 	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
221 	if (err)
222 		return err;
223 
224 	if (imsg_flush(ibuf) == -1) {
225 		imsg_clear(ibuf);
226 		return got_error_from_errno("imsg_flush");
227 	}
228 
229 	return NULL;
230 }
231 
232 const struct got_error *
233 got_privsep_flush_imsg(struct imsgbuf *ibuf)
234 {
235 	return flush_imsg(ibuf);
236 }
237 
238 const struct got_error *
239 got_privsep_send_stop(int fd)
240 {
241 	const struct got_error *err = NULL;
242 	struct imsgbuf ibuf;
243 
244 	imsg_init(&ibuf, fd);
245 
246 	if (imsg_compose(&ibuf, GOT_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
247 		return got_error_from_errno("imsg_compose STOP");
248 
249 	err = flush_imsg(&ibuf);
250 	return err;
251 }
252 
253 const struct got_error *
254 got_privsep_send_obj_req(struct imsgbuf *ibuf, int fd,
255     struct got_object_id *id)
256 {
257 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_REQUEST, 0, 0, fd,
258 	    id, sizeof(*id)) == -1)
259 		return got_error_from_errno("imsg_compose OBJECT_REQUEST");
260 
261 	return flush_imsg(ibuf);
262 }
263 
264 const struct got_error *
265 got_privsep_send_raw_obj_req(struct imsgbuf *ibuf, int fd,
266     struct got_object_id *id)
267 {
268 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_REQUEST, 0, 0, fd,
269 	    id, sizeof(*id)) == -1)
270 		return got_error_from_errno("imsg_compose RAW_OBJECT_REQUEST");
271 
272 	return flush_imsg(ibuf);
273 }
274 
275 const struct got_error *
276 got_privsep_send_raw_obj_outfd(struct imsgbuf *ibuf, int outfd)
277 {
278 	const struct got_error *err = NULL;
279 
280 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_OUTFD, 0, 0, outfd, NULL, 0)
281 	    == -1) {
282 		err = got_error_from_errno("imsg_compose RAW_OBJECT_OUTFD");
283 		close(outfd);
284 		return err;
285 	}
286 
287 	return flush_imsg(ibuf);
288 }
289 
290 const struct got_error *
291 got_privsep_send_raw_obj(struct imsgbuf *ibuf, off_t size, size_t hdrlen,
292     uint8_t *data)
293 {
294 	const struct got_error *err = NULL;
295 	struct got_imsg_raw_obj iobj;
296 	size_t len = sizeof(iobj);
297 	struct ibuf *wbuf;
298 
299 	iobj.hdrlen = hdrlen;
300 	iobj.size = size;
301 
302 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX)
303 		len += (size_t)size + hdrlen;
304 
305 	wbuf = imsg_create(ibuf, GOT_IMSG_RAW_OBJECT, 0, 0, len);
306 	if (wbuf == NULL) {
307 		err = got_error_from_errno("imsg_create RAW_OBJECT");
308 		return err;
309 	}
310 
311 	if (imsg_add(wbuf, &iobj, sizeof(iobj)) == -1) {
312 		err = got_error_from_errno("imsg_add RAW_OBJECT");
313 		ibuf_free(wbuf);
314 		return err;
315 	}
316 
317 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
318 		if (imsg_add(wbuf, data, size + hdrlen) == -1) {
319 			err = got_error_from_errno("imsg_add RAW_OBJECT");
320 			ibuf_free(wbuf);
321 			return err;
322 		}
323 	}
324 
325 	wbuf->fd = -1;
326 	imsg_close(ibuf, wbuf);
327 
328 	return flush_imsg(ibuf);
329 }
330 
331 const struct got_error *
332 got_privsep_recv_raw_obj(uint8_t **outbuf, off_t *size, size_t *hdrlen,
333     struct imsgbuf *ibuf)
334 {
335 	const struct got_error *err = NULL;
336 	struct imsg imsg;
337 	struct got_imsg_raw_obj *iobj;
338 	size_t datalen;
339 
340 	*outbuf = NULL;
341 
342 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
343 	if (err)
344 		return err;
345 
346 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
347 
348 	switch (imsg.hdr.type) {
349 	case GOT_IMSG_RAW_OBJECT:
350 		if (datalen < sizeof(*iobj)) {
351 			err = got_error(GOT_ERR_PRIVSEP_LEN);
352 			break;
353 		}
354 		iobj = imsg.data;
355 		*size = iobj->size;
356 		*hdrlen = iobj->hdrlen;
357 
358 		if (datalen == sizeof(*iobj)) {
359 			/* Data has been written to file descriptor. */
360 			break;
361 		}
362 
363 		if (*size + *hdrlen > GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
364 			err = got_error(GOT_ERR_PRIVSEP_LEN);
365 			break;
366 		}
367 
368 		*outbuf = malloc(*size + *hdrlen);
369 		if (*outbuf == NULL) {
370 			err = got_error_from_errno("malloc");
371 			break;
372 		}
373 		memcpy(*outbuf, imsg.data + sizeof(*iobj), *size + *hdrlen);
374 		break;
375 	default:
376 		err = got_error(GOT_ERR_PRIVSEP_MSG);
377 		break;
378 	}
379 
380 	imsg_free(&imsg);
381 
382 	return err;
383 }
384 
385 const struct got_error *
386 got_privsep_send_commit_req(struct imsgbuf *ibuf, int fd,
387     struct got_object_id *id, int pack_idx)
388 {
389 	const struct got_error *err = NULL;
390 	struct got_imsg_packed_object iobj;
391 	void *data;
392 	size_t len;
393 
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 	const struct got_error *err = NULL;
419 	struct ibuf *wbuf;
420 	size_t len;
421 
422 	if (pack_idx != -1)
423 		len = sizeof(struct got_imsg_packed_object);
424 	else
425 		len = sizeof(*id);
426 
427 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_REQUEST, 0, 0, len);
428 	if (wbuf == NULL)
429 		return got_error_from_errno("imsg_create TREE_REQUEST");
430 
431 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
432 		err = got_error_from_errno("imsg_add TREE_REQUEST");
433 		ibuf_free(wbuf);
434 		return err;
435 	}
436 
437 	if (pack_idx != -1) { /* tree is packed */
438 		if (imsg_add(wbuf, &pack_idx, sizeof(pack_idx)) == -1) {
439 			err = got_error_from_errno("imsg_add TREE_REQUEST");
440 			ibuf_free(wbuf);
441 			return err;
442 		}
443 	}
444 
445 	wbuf->fd = fd;
446 	imsg_close(ibuf, wbuf);
447 
448 	return flush_imsg(ibuf);
449 }
450 
451 const struct got_error *
452 got_privsep_send_tag_req(struct imsgbuf *ibuf, int fd,
453     struct got_object_id *id, int pack_idx)
454 {
455 	struct got_imsg_packed_object iobj;
456 	void *data;
457 	size_t len;
458 
459 	if (pack_idx != -1) { /* tag is packed */
460 		iobj.idx = pack_idx;
461 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
462 		data = &iobj;
463 		len = sizeof(iobj);
464 	} else {
465 		data = id;
466 		len = sizeof(*id);
467 	}
468 
469 	if (imsg_compose(ibuf, GOT_IMSG_TAG_REQUEST, 0, 0, fd, data, len)
470 	    == -1)
471 		return got_error_from_errno("imsg_compose TAG_REQUEST");
472 
473 	return flush_imsg(ibuf);
474 }
475 
476 const struct got_error *
477 got_privsep_send_blob_req(struct imsgbuf *ibuf, int infd,
478     struct got_object_id *id, int pack_idx)
479 {
480 	const struct got_error *err = NULL;
481 	struct got_imsg_packed_object iobj;
482 	void *data;
483 	size_t len;
484 
485 	if (pack_idx != -1) { /* blob is packed */
486 		iobj.idx = pack_idx;
487 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
488 		data = &iobj;
489 		len = sizeof(iobj);
490 	} else {
491 		data = id;
492 		len = sizeof(*id);
493 	}
494 
495 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_REQUEST, 0, 0, infd, data, len)
496 	    == -1) {
497 		err = got_error_from_errno("imsg_compose BLOB_REQUEST");
498 		close(infd);
499 		return err;
500 	}
501 
502 	return flush_imsg(ibuf);
503 }
504 
505 const struct got_error *
506 got_privsep_send_blob_outfd(struct imsgbuf *ibuf, int outfd)
507 {
508 	const struct got_error *err = NULL;
509 
510 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_OUTFD, 0, 0, outfd, NULL, 0)
511 	    == -1) {
512 		err = got_error_from_errno("imsg_compose BLOB_OUTFD");
513 		close(outfd);
514 		return err;
515 	}
516 
517 	return flush_imsg(ibuf);
518 }
519 
520 static const struct got_error *
521 send_fd(struct imsgbuf *ibuf, int imsg_code, int fd)
522 {
523 	const struct got_error *err = NULL;
524 
525 	if (imsg_compose(ibuf, imsg_code, 0, 0, fd, NULL, 0) == -1) {
526 		err = got_error_from_errno("imsg_compose TMPFD");
527 		close(fd);
528 		return err;
529 	}
530 
531 	return flush_imsg(ibuf);
532 }
533 
534 const struct got_error *
535 got_privsep_send_tmpfd(struct imsgbuf *ibuf, int fd)
536 {
537 	return send_fd(ibuf, GOT_IMSG_TMPFD, fd);
538 }
539 
540 const struct got_error *
541 got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj)
542 {
543 	struct got_imsg_object iobj;
544 
545 	memcpy(iobj.id, obj->id.sha1, sizeof(iobj.id));
546 	iobj.type = obj->type;
547 	iobj.flags = obj->flags;
548 	iobj.hdrlen = obj->hdrlen;
549 	iobj.size = obj->size;
550 	if (iobj.flags & GOT_OBJ_FLAG_PACKED) {
551 		iobj.pack_offset = obj->pack_offset;
552 		iobj.pack_idx = obj->pack_idx;
553 	}
554 
555 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
556 	    == -1)
557 		return got_error_from_errno("imsg_compose OBJECT");
558 
559 	return flush_imsg(ibuf);
560 }
561 
562 const struct got_error *
563 got_privsep_send_fetch_req(struct imsgbuf *ibuf, int fd,
564     struct got_pathlist_head *have_refs, int fetch_all_branches,
565     struct got_pathlist_head *wanted_branches,
566     struct got_pathlist_head *wanted_refs, int list_refs_only, int verbosity)
567 {
568 	const struct got_error *err = NULL;
569 	struct ibuf *wbuf;
570 	size_t len;
571 	struct got_pathlist_entry *pe;
572 	struct got_imsg_fetch_request fetchreq;
573 
574 	memset(&fetchreq, 0, sizeof(fetchreq));
575 	fetchreq.fetch_all_branches = fetch_all_branches;
576 	fetchreq.list_refs_only = list_refs_only;
577 	fetchreq.verbosity = verbosity;
578 	TAILQ_FOREACH(pe, have_refs, entry)
579 		fetchreq.n_have_refs++;
580 	TAILQ_FOREACH(pe, wanted_branches, entry)
581 		fetchreq.n_wanted_branches++;
582 	TAILQ_FOREACH(pe, wanted_refs, entry)
583 		fetchreq.n_wanted_refs++;
584 	len = sizeof(struct got_imsg_fetch_request);
585 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
586 		close(fd);
587 		return got_error(GOT_ERR_NO_SPACE);
588 	}
589 
590 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_REQUEST, 0, 0, fd,
591 	    &fetchreq, sizeof(fetchreq)) == -1)
592 		return got_error_from_errno(
593 		    "imsg_compose FETCH_SERVER_PROGRESS");
594 
595 	err = flush_imsg(ibuf);
596 	if (err) {
597 		close(fd);
598 		return err;
599 	}
600 	fd = -1;
601 
602 	TAILQ_FOREACH(pe, have_refs, entry) {
603 		const char *name = pe->path;
604 		size_t name_len = pe->path_len;
605 		struct got_object_id *id = pe->data;
606 
607 		len = sizeof(struct got_imsg_fetch_have_ref) + name_len;
608 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_HAVE_REF, 0, 0, len);
609 		if (wbuf == NULL)
610 			return got_error_from_errno("imsg_create FETCH_HAVE_REF");
611 
612 		/* Keep in sync with struct got_imsg_fetch_have_ref! */
613 		if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1) {
614 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
615 			ibuf_free(wbuf);
616 			return err;
617 		}
618 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
619 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
620 			ibuf_free(wbuf);
621 			return err;
622 		}
623 		if (imsg_add(wbuf, name, name_len) == -1) {
624 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
625 			ibuf_free(wbuf);
626 			return err;
627 		}
628 
629 		wbuf->fd = -1;
630 		imsg_close(ibuf, wbuf);
631 		err = flush_imsg(ibuf);
632 		if (err)
633 			return err;
634 	}
635 
636 	TAILQ_FOREACH(pe, wanted_branches, entry) {
637 		const char *name = pe->path;
638 		size_t name_len = pe->path_len;
639 
640 		len = sizeof(struct got_imsg_fetch_wanted_branch) + name_len;
641 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_BRANCH, 0, 0,
642 		    len);
643 		if (wbuf == NULL)
644 			return got_error_from_errno(
645 			    "imsg_create FETCH_WANTED_BRANCH");
646 
647 		/* Keep in sync with struct got_imsg_fetch_wanted_branch! */
648 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
649 			err = got_error_from_errno(
650 			    "imsg_add FETCH_WANTED_BRANCH");
651 			ibuf_free(wbuf);
652 			return err;
653 		}
654 		if (imsg_add(wbuf, name, name_len) == -1) {
655 			err = got_error_from_errno(
656 			    "imsg_add FETCH_WANTED_BRANCH");
657 			ibuf_free(wbuf);
658 			return err;
659 		}
660 
661 		wbuf->fd = -1;
662 		imsg_close(ibuf, wbuf);
663 		err = flush_imsg(ibuf);
664 		if (err)
665 			return err;
666 	}
667 
668 	TAILQ_FOREACH(pe, wanted_refs, entry) {
669 		const char *name = pe->path;
670 		size_t name_len = pe->path_len;
671 
672 		len = sizeof(struct got_imsg_fetch_wanted_ref) + name_len;
673 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_REF, 0, 0,
674 		    len);
675 		if (wbuf == NULL)
676 			return got_error_from_errno(
677 			    "imsg_create FETCH_WANTED_REF");
678 
679 		/* Keep in sync with struct got_imsg_fetch_wanted_ref! */
680 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
681 			err = got_error_from_errno(
682 			    "imsg_add FETCH_WANTED_REF");
683 			ibuf_free(wbuf);
684 			return err;
685 		}
686 		if (imsg_add(wbuf, name, name_len) == -1) {
687 			err = got_error_from_errno(
688 			    "imsg_add FETCH_WANTED_REF");
689 			ibuf_free(wbuf);
690 			return err;
691 		}
692 
693 		wbuf->fd = -1;
694 		imsg_close(ibuf, wbuf);
695 		err = flush_imsg(ibuf);
696 		if (err)
697 			return err;
698 	}
699 
700 
701 	return NULL;
702 
703 }
704 
705 const struct got_error *
706 got_privsep_send_fetch_outfd(struct imsgbuf *ibuf, int fd)
707 {
708 	return send_fd(ibuf, GOT_IMSG_FETCH_OUTFD, fd);
709 }
710 
711 const struct got_error *
712 got_privsep_recv_fetch_progress(int *done, struct got_object_id **id,
713     char **refname, struct got_pathlist_head *symrefs, char **server_progress,
714     off_t *packfile_size, uint8_t *pack_sha1, struct imsgbuf *ibuf)
715 {
716 	const struct got_error *err = NULL;
717 	struct imsg imsg;
718 	size_t datalen;
719 	struct got_imsg_fetch_symrefs *isymrefs = NULL;
720 	size_t n, remain;
721 	off_t off;
722 	int i;
723 
724 	*done = 0;
725 	*id = NULL;
726 	*refname = NULL;
727 	*server_progress = NULL;
728 	*packfile_size = 0;
729 	memset(pack_sha1, 0, SHA1_DIGEST_LENGTH);
730 
731 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
732 	if (err)
733 		return err;
734 
735 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
736 	switch (imsg.hdr.type) {
737 	case GOT_IMSG_ERROR:
738 		if (datalen < sizeof(struct got_imsg_error)) {
739 			err = got_error(GOT_ERR_PRIVSEP_LEN);
740 			break;
741 		}
742 		err = recv_imsg_error(&imsg, datalen);
743 		break;
744 	case GOT_IMSG_FETCH_SYMREFS:
745 		if (datalen < sizeof(*isymrefs)) {
746 			err = got_error(GOT_ERR_PRIVSEP_LEN);
747 			break;
748 		}
749 		if (isymrefs != NULL) {
750 			err = got_error(GOT_ERR_PRIVSEP_MSG);
751 			break;
752 		}
753 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
754 		off = sizeof(*isymrefs);
755 		remain = datalen - off;
756 		for (n = 0; n < isymrefs->nsymrefs; n++) {
757 			struct got_imsg_fetch_symref *s;
758 			char *name, *target;
759 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
760 				err = got_error(GOT_ERR_PRIVSEP_LEN);
761 				goto done;
762 			}
763 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
764 			off += sizeof(*s);
765 			remain -= sizeof(*s);
766 			if (remain < s->name_len) {
767 				err = got_error(GOT_ERR_PRIVSEP_LEN);
768 				goto done;
769 			}
770 			name = strndup(imsg.data + off, s->name_len);
771 			if (name == NULL) {
772 				err = got_error_from_errno("strndup");
773 				goto done;
774 			}
775 			off += s->name_len;
776 			remain -= s->name_len;
777 			if (remain < s->target_len) {
778 				err = got_error(GOT_ERR_PRIVSEP_LEN);
779 				free(name);
780 				goto done;
781 			}
782 			target = strndup(imsg.data + off, s->target_len);
783 			if (target == NULL) {
784 				err = got_error_from_errno("strndup");
785 				free(name);
786 				goto done;
787 			}
788 			off += s->target_len;
789 			remain -= s->target_len;
790 			err = got_pathlist_append(symrefs, name, target);
791 			if (err) {
792 				free(name);
793 				free(target);
794 				goto done;
795 			}
796 		}
797 		break;
798 	case GOT_IMSG_FETCH_REF:
799 		if (datalen <= SHA1_DIGEST_LENGTH) {
800 			err = got_error(GOT_ERR_PRIVSEP_MSG);
801 			break;
802 		}
803 		*id = malloc(sizeof(**id));
804 		if (*id == NULL) {
805 			err = got_error_from_errno("malloc");
806 			break;
807 		}
808 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
809 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
810 		    datalen - SHA1_DIGEST_LENGTH);
811 		if (*refname == NULL) {
812 			err = got_error_from_errno("strndup");
813 			break;
814 		}
815 		break;
816 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
817 		if (datalen == 0) {
818 			err = got_error(GOT_ERR_PRIVSEP_LEN);
819 			break;
820 		}
821 		*server_progress = strndup(imsg.data, datalen);
822 		if (*server_progress == NULL) {
823 			err = got_error_from_errno("strndup");
824 			break;
825 		}
826 		for (i = 0; i < datalen; i++) {
827 			if (!isprint((unsigned char)(*server_progress)[i]) &&
828 			    !isspace((unsigned char)(*server_progress)[i])) {
829 				err = got_error(GOT_ERR_PRIVSEP_MSG);
830 				free(*server_progress);
831 				*server_progress = NULL;
832 				goto done;
833 			}
834 		}
835 		break;
836 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
837 		if (datalen < sizeof(*packfile_size)) {
838 			err = got_error(GOT_ERR_PRIVSEP_MSG);
839 			break;
840 		}
841 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
842 		break;
843 	case GOT_IMSG_FETCH_DONE:
844 		if (datalen != SHA1_DIGEST_LENGTH) {
845 			err = got_error(GOT_ERR_PRIVSEP_MSG);
846 			break;
847 		}
848 		memcpy(pack_sha1, imsg.data, SHA1_DIGEST_LENGTH);
849 		*done = 1;
850 		break;
851 	default:
852 		err = got_error(GOT_ERR_PRIVSEP_MSG);
853 		break;
854 	}
855 done:
856 	if (err) {
857 		free(*id);
858 		*id = NULL;
859 		free(*refname);
860 		*refname = NULL;
861 	}
862 	imsg_free(&imsg);
863 	return err;
864 }
865 
866 static const struct got_error *
867 send_send_ref(const char *name, size_t name_len, struct got_object_id *id,
868     int delete, struct imsgbuf *ibuf)
869 {
870 	const struct got_error *err = NULL;
871 	size_t len;
872 	struct ibuf *wbuf;
873 
874 	len = sizeof(struct got_imsg_send_ref) + name_len;
875 	wbuf = imsg_create(ibuf, GOT_IMSG_SEND_REF, 0, 0, len);
876 	if (wbuf == NULL)
877 		return got_error_from_errno("imsg_create SEND_REF");
878 
879 	/* Keep in sync with struct got_imsg_send_ref! */
880 	if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1) {
881 		err = got_error_from_errno("imsg_add SEND_REF");
882 		ibuf_free(wbuf);
883 		return err;
884 	}
885 	if (imsg_add(wbuf, &delete, sizeof(delete)) == -1) {
886 		err = got_error_from_errno("imsg_add SEND_REF");
887 		ibuf_free(wbuf);
888 		return err;
889 	}
890 	if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
891 		err = got_error_from_errno("imsg_add SEND_REF");
892 		ibuf_free(wbuf);
893 		return err;
894 	}
895 	if (imsg_add(wbuf, name, name_len) == -1) {
896 		err = got_error_from_errno("imsg_add SEND_REF");
897 		ibuf_free(wbuf);
898 		return err;
899 	}
900 
901 	wbuf->fd = -1;
902 	imsg_close(ibuf, wbuf);
903 	return flush_imsg(ibuf);
904 }
905 
906 const struct got_error *
907 got_privsep_send_send_req(struct imsgbuf *ibuf, int fd,
908     struct got_pathlist_head *have_refs,
909     struct got_pathlist_head *delete_refs,
910     int verbosity)
911 {
912 	const struct got_error *err = NULL;
913 	struct got_pathlist_entry *pe;
914 	struct got_imsg_send_request sendreq;
915 	struct got_object_id zero_id;
916 
917 	memset(&zero_id, 0, sizeof(zero_id));
918 	memset(&sendreq, 0, sizeof(sendreq));
919 	sendreq.verbosity = verbosity;
920 	TAILQ_FOREACH(pe, have_refs, entry)
921 		sendreq.nrefs++;
922 	TAILQ_FOREACH(pe, delete_refs, entry)
923 		sendreq.nrefs++;
924 	if (imsg_compose(ibuf, GOT_IMSG_SEND_REQUEST, 0, 0, fd,
925 	    &sendreq, sizeof(sendreq)) == -1) {
926 		err = got_error_from_errno(
927 		    "imsg_compose FETCH_SERVER_PROGRESS");
928 		goto done;
929 	}
930 
931 	err = flush_imsg(ibuf);
932 	if (err)
933 		goto done;
934 	fd = -1;
935 
936 	TAILQ_FOREACH(pe, have_refs, entry) {
937 		const char *name = pe->path;
938 		size_t name_len = pe->path_len;
939 		struct got_object_id *id = pe->data;
940 		err = send_send_ref(name, name_len, id, 0, ibuf);
941 		if (err)
942 			goto done;
943 	}
944 
945 	TAILQ_FOREACH(pe, delete_refs, entry) {
946 		const char *name = pe->path;
947 		size_t name_len = pe->path_len;
948 		err = send_send_ref(name, name_len, &zero_id, 1, ibuf);
949 		if (err)
950 			goto done;
951 	}
952 done:
953 	if (fd != -1 && close(fd) == -1 && err == NULL)
954 		err = got_error_from_errno("close");
955 	return err;
956 
957 }
958 
959 const struct got_error *
960 got_privsep_recv_send_remote_refs(struct got_pathlist_head *remote_refs,
961     struct imsgbuf *ibuf)
962 {
963 	const struct got_error *err = NULL;
964 	struct imsg imsg;
965 	size_t datalen;
966 	int done = 0;
967 	struct got_imsg_send_remote_ref iremote_ref;
968 	struct got_object_id *id = NULL;
969 	char *refname = NULL;
970 	struct got_pathlist_entry *new;
971 
972 	while (!done) {
973 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
974 		if (err)
975 			return err;
976 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
977 		switch (imsg.hdr.type) {
978 		case GOT_IMSG_ERROR:
979 			if (datalen < sizeof(struct got_imsg_error)) {
980 				err = got_error(GOT_ERR_PRIVSEP_LEN);
981 				goto done;
982 			}
983 			err = recv_imsg_error(&imsg, datalen);
984 			goto done;
985 		case GOT_IMSG_SEND_REMOTE_REF:
986 			if (datalen < sizeof(iremote_ref)) {
987 				err = got_error(GOT_ERR_PRIVSEP_MSG);
988 				goto done;
989 			}
990 			memcpy(&iremote_ref, imsg.data, sizeof(iremote_ref));
991 			if (datalen != sizeof(iremote_ref) +
992 			    iremote_ref.name_len) {
993 				err = got_error(GOT_ERR_PRIVSEP_MSG);
994 				goto done;
995 			}
996 			id = malloc(sizeof(*id));
997 			if (id == NULL) {
998 				err = got_error_from_errno("malloc");
999 				goto done;
1000 			}
1001 			memcpy(id->sha1, iremote_ref.id, SHA1_DIGEST_LENGTH);
1002 			refname = strndup(imsg.data + sizeof(iremote_ref),
1003 			    datalen - sizeof(iremote_ref));
1004 			if (refname == NULL) {
1005 				err = got_error_from_errno("strndup");
1006 				goto done;
1007 			}
1008 			err = got_pathlist_insert(&new, remote_refs,
1009 			    refname, id);
1010 			if (err)
1011 				goto done;
1012 			if (new == NULL) { /* duplicate which wasn't inserted */
1013 				free(id);
1014 				free(refname);
1015 			}
1016 			id = NULL;
1017 			refname = NULL;
1018 			break;
1019 		case GOT_IMSG_SEND_PACK_REQUEST:
1020 			if (datalen != 0) {
1021 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1022 				goto done;
1023 			}
1024 			/* got-send-pack is now waiting for a pack file. */
1025 			done = 1;
1026 			break;
1027 		default:
1028 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1029 			break;
1030 		}
1031 	}
1032 done:
1033 	free(id);
1034 	free(refname);
1035 	imsg_free(&imsg);
1036 	return err;
1037 }
1038 
1039 const struct got_error *
1040 got_privsep_send_packfd(struct imsgbuf *ibuf, int fd)
1041 {
1042 	return send_fd(ibuf, GOT_IMSG_SEND_PACKFD, fd);
1043 }
1044 
1045 const struct got_error *
1046 got_privsep_recv_send_progress(int *done, off_t *bytes_sent,
1047     int *success, char **refname, struct imsgbuf *ibuf)
1048 {
1049 	const struct got_error *err = NULL;
1050 	struct imsg imsg;
1051 	size_t datalen;
1052 	struct got_imsg_send_ref_status iref_status;
1053 
1054 	/* Do not reset the current value of 'bytes_sent', it accumulates. */
1055 	*done = 0;
1056 	*success = 0;
1057 	*refname = NULL;
1058 
1059 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1060 	if (err)
1061 		return err;
1062 
1063 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1064 	switch (imsg.hdr.type) {
1065 	case GOT_IMSG_ERROR:
1066 		if (datalen < sizeof(struct got_imsg_error)) {
1067 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1068 			break;
1069 		}
1070 		err = recv_imsg_error(&imsg, datalen);
1071 		break;
1072 	case GOT_IMSG_SEND_UPLOAD_PROGRESS:
1073 		if (datalen < sizeof(*bytes_sent)) {
1074 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1075 			break;
1076 		}
1077 		memcpy(bytes_sent, imsg.data, sizeof(*bytes_sent));
1078 		break;
1079 	case GOT_IMSG_SEND_REF_STATUS:
1080 		if (datalen < sizeof(iref_status)) {
1081 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1082 			break;
1083 		}
1084 		memcpy(&iref_status, imsg.data, sizeof(iref_status));
1085 		if (datalen != sizeof(iref_status) + iref_status.name_len) {
1086 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1087 			break;
1088 		}
1089 		*success = iref_status.success;
1090 		*refname = strndup(imsg.data + sizeof(iref_status),
1091 		    iref_status.name_len);
1092 		break;
1093 	case GOT_IMSG_SEND_DONE:
1094 		if (datalen != 0) {
1095 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1096 			break;
1097 		}
1098 		*done = 1;
1099 		break;
1100 	default:
1101 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1102 		break;
1103 	}
1104 
1105 	imsg_free(&imsg);
1106 	return err;
1107 }
1108 
1109 const struct got_error *
1110 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_sha1,
1111     int fd)
1112 {
1113 	const struct got_error *err = NULL;
1114 
1115 	/* Keep in sync with struct got_imsg_index_pack_request */
1116 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
1117 	    pack_sha1, SHA1_DIGEST_LENGTH) == -1) {
1118 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
1119 		close(fd);
1120 		return err;
1121 	}
1122 	return flush_imsg(ibuf);
1123 }
1124 
1125 const struct got_error *
1126 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
1127 {
1128 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
1129 }
1130 
1131 const struct got_error *
1132 got_privsep_recv_index_progress(int *done, int *nobj_total,
1133     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
1134     struct imsgbuf *ibuf)
1135 {
1136 	const struct got_error *err = NULL;
1137 	struct imsg imsg;
1138 	struct got_imsg_index_pack_progress *iprogress;
1139 	size_t datalen;
1140 
1141 	*done = 0;
1142 	*nobj_total = 0;
1143 	*nobj_indexed = 0;
1144 	*nobj_resolved = 0;
1145 
1146 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1147 	if (err)
1148 		return err;
1149 
1150 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1151 	switch (imsg.hdr.type) {
1152 	case GOT_IMSG_ERROR:
1153 		if (datalen < sizeof(struct got_imsg_error)) {
1154 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1155 			break;
1156 		}
1157 		err = recv_imsg_error(&imsg, datalen);
1158 		break;
1159 	case GOT_IMSG_IDXPACK_PROGRESS:
1160 		if (datalen < sizeof(*iprogress)) {
1161 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1162 			break;
1163 		}
1164 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
1165 		*nobj_total = iprogress->nobj_total;
1166 		*nobj_indexed = iprogress->nobj_indexed;
1167 		*nobj_loose = iprogress->nobj_loose;
1168 		*nobj_resolved = iprogress->nobj_resolved;
1169 		break;
1170 	case GOT_IMSG_IDXPACK_DONE:
1171 		if (datalen != 0) {
1172 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1173 			break;
1174 		}
1175 		*done = 1;
1176 		break;
1177 	default:
1178 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1179 		break;
1180 	}
1181 
1182 	imsg_free(&imsg);
1183 	return err;
1184 }
1185 
1186 const struct got_error *
1187 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
1188     struct imsgbuf *ibuf)
1189 {
1190 	struct got_imsg_object *iobj;
1191 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
1192 
1193 	if (datalen != sizeof(*iobj))
1194 		return got_error(GOT_ERR_PRIVSEP_LEN);
1195 	iobj = imsg->data;
1196 
1197 	*obj = calloc(1, sizeof(**obj));
1198 	if (*obj == NULL)
1199 		return got_error_from_errno("calloc");
1200 
1201 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
1202 	(*obj)->type = iobj->type;
1203 	(*obj)->flags = iobj->flags;
1204 	(*obj)->hdrlen = iobj->hdrlen;
1205 	(*obj)->size = iobj->size;
1206 	/* path_packfile is handled by caller */
1207 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
1208 		(*obj)->pack_offset = iobj->pack_offset;
1209 		(*obj)->pack_idx = iobj->pack_idx;
1210 	}
1211 	STAILQ_INIT(&(*obj)->deltas.entries);
1212 	return NULL;
1213 }
1214 
1215 const struct got_error *
1216 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
1217 {
1218 	const struct got_error *err = NULL;
1219 	struct imsg imsg;
1220 	const size_t min_datalen =
1221 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
1222 
1223 	*obj = NULL;
1224 
1225 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1226 	if (err)
1227 		return err;
1228 
1229 	switch (imsg.hdr.type) {
1230 	case GOT_IMSG_OBJECT:
1231 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
1232 		break;
1233 	default:
1234 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1235 		break;
1236 	}
1237 
1238 	imsg_free(&imsg);
1239 
1240 	return err;
1241 }
1242 
1243 static const struct got_error *
1244 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
1245     size_t logmsg_len)
1246 {
1247 	const struct got_error *err = NULL;
1248 	size_t offset, remain;
1249 
1250 	offset = 0;
1251 	remain = logmsg_len;
1252 	while (remain > 0) {
1253 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1254 
1255 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
1256 		    commit->logmsg + offset, n) == -1) {
1257 			err = got_error_from_errno("imsg_compose "
1258 			    "COMMIT_LOGMSG");
1259 			break;
1260 		}
1261 
1262 		err = flush_imsg(ibuf);
1263 		if (err)
1264 			break;
1265 
1266 		offset += n;
1267 		remain -= n;
1268 	}
1269 
1270 	return err;
1271 }
1272 
1273 const struct got_error *
1274 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
1275 {
1276 	const struct got_error *err = NULL;
1277 	struct got_imsg_commit_object *icommit;
1278 	uint8_t *buf;
1279 	size_t len, total;
1280 	struct got_object_qid *qid;
1281 	size_t author_len = strlen(commit->author);
1282 	size_t committer_len = strlen(commit->committer);
1283 	size_t logmsg_len = strlen(commit->logmsg);
1284 
1285 	total = sizeof(*icommit) + author_len + committer_len +
1286 	    commit->nparents * SHA1_DIGEST_LENGTH;
1287 
1288 	buf = malloc(total);
1289 	if (buf == NULL)
1290 		return got_error_from_errno("malloc");
1291 
1292 	icommit = (struct got_imsg_commit_object *)buf;
1293 	memcpy(icommit->tree_id, commit->tree_id->sha1,
1294 	    sizeof(icommit->tree_id));
1295 	icommit->author_len = author_len;
1296 	icommit->author_time = commit->author_time;
1297 	icommit->author_gmtoff = commit->author_gmtoff;
1298 	icommit->committer_len = committer_len;
1299 	icommit->committer_time = commit->committer_time;
1300 	icommit->committer_gmtoff = commit->committer_gmtoff;
1301 	icommit->logmsg_len = logmsg_len;
1302 	icommit->nparents = commit->nparents;
1303 
1304 	len = sizeof(*icommit);
1305 	memcpy(buf + len, commit->author, author_len);
1306 	len += author_len;
1307 	memcpy(buf + len, commit->committer, committer_len);
1308 	len += committer_len;
1309 	STAILQ_FOREACH(qid, &commit->parent_ids, entry) {
1310 		memcpy(buf + len, &qid->id, SHA1_DIGEST_LENGTH);
1311 		len += SHA1_DIGEST_LENGTH;
1312 	}
1313 
1314 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
1315 		err = got_error_from_errno("imsg_compose COMMIT");
1316 		goto done;
1317 	}
1318 
1319 	if (logmsg_len == 0 ||
1320 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1321 		err = flush_imsg(ibuf);
1322 		if (err)
1323 			goto done;
1324 	}
1325 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
1326 done:
1327 	free(buf);
1328 	return err;
1329 }
1330 
1331 static const struct got_error *
1332 get_commit_from_imsg(struct got_commit_object **commit,
1333     struct imsg *imsg, size_t datalen, struct imsgbuf *ibuf)
1334 {
1335 	const struct got_error *err = NULL;
1336 	struct got_imsg_commit_object *icommit;
1337 	size_t len = 0;
1338 	int i;
1339 
1340 	if (datalen < sizeof(*icommit))
1341 		return got_error(GOT_ERR_PRIVSEP_LEN);
1342 
1343 	icommit = imsg->data;
1344 	if (datalen != sizeof(*icommit) + icommit->author_len +
1345 	    icommit->committer_len +
1346 	    icommit->nparents * SHA1_DIGEST_LENGTH)
1347 		return got_error(GOT_ERR_PRIVSEP_LEN);
1348 
1349 	if (icommit->nparents < 0)
1350 		return got_error(GOT_ERR_PRIVSEP_LEN);
1351 
1352 	len += sizeof(*icommit);
1353 
1354 	*commit = got_object_commit_alloc_partial();
1355 	if (*commit == NULL)
1356 		return got_error_from_errno(
1357 		    "got_object_commit_alloc_partial");
1358 
1359 	memcpy((*commit)->tree_id->sha1, icommit->tree_id,
1360 	    SHA1_DIGEST_LENGTH);
1361 	(*commit)->author_time = icommit->author_time;
1362 	(*commit)->author_gmtoff = icommit->author_gmtoff;
1363 	(*commit)->committer_time = icommit->committer_time;
1364 	(*commit)->committer_gmtoff = icommit->committer_gmtoff;
1365 
1366 	if (icommit->author_len == 0) {
1367 		(*commit)->author = strdup("");
1368 		if ((*commit)->author == NULL) {
1369 			err = got_error_from_errno("strdup");
1370 			goto done;
1371 		}
1372 	} else {
1373 		(*commit)->author = malloc(icommit->author_len + 1);
1374 		if ((*commit)->author == NULL) {
1375 			err = got_error_from_errno("malloc");
1376 			goto done;
1377 		}
1378 		memcpy((*commit)->author, imsg->data + len,
1379 		    icommit->author_len);
1380 		(*commit)->author[icommit->author_len] = '\0';
1381 	}
1382 	len += icommit->author_len;
1383 
1384 	if (icommit->committer_len == 0) {
1385 		(*commit)->committer = strdup("");
1386 		if ((*commit)->committer == NULL) {
1387 			err = got_error_from_errno("strdup");
1388 			goto done;
1389 		}
1390 	} else {
1391 		(*commit)->committer =
1392 		    malloc(icommit->committer_len + 1);
1393 		if ((*commit)->committer == NULL) {
1394 			err = got_error_from_errno("malloc");
1395 			goto done;
1396 		}
1397 		memcpy((*commit)->committer, imsg->data + len,
1398 		    icommit->committer_len);
1399 		(*commit)->committer[icommit->committer_len] = '\0';
1400 	}
1401 	len += icommit->committer_len;
1402 
1403 	if (icommit->logmsg_len == 0) {
1404 		(*commit)->logmsg = strdup("");
1405 		if ((*commit)->logmsg == NULL) {
1406 			err = got_error_from_errno("strdup");
1407 			goto done;
1408 		}
1409 	} else {
1410 		size_t offset = 0, remain = icommit->logmsg_len;
1411 
1412 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1413 		if ((*commit)->logmsg == NULL) {
1414 			err = got_error_from_errno("malloc");
1415 			goto done;
1416 		}
1417 		while (remain > 0) {
1418 			struct imsg imsg_log;
1419 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1420 			    remain);
1421 
1422 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1423 			if (err)
1424 				goto done;
1425 
1426 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1427 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1428 				goto done;
1429 			}
1430 
1431 			memcpy((*commit)->logmsg + offset,
1432 			    imsg_log.data, n);
1433 			imsg_free(&imsg_log);
1434 			offset += n;
1435 			remain -= n;
1436 		}
1437 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1438 	}
1439 
1440 	for (i = 0; i < icommit->nparents; i++) {
1441 		struct got_object_qid *qid;
1442 
1443 		err = got_object_qid_alloc_partial(&qid);
1444 		if (err)
1445 			break;
1446 		memcpy(&qid->id, imsg->data + len +
1447 		    i * SHA1_DIGEST_LENGTH, sizeof(qid->id));
1448 		STAILQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1449 		(*commit)->nparents++;
1450 	}
1451 done:
1452 	if (err) {
1453 		got_object_commit_close(*commit);
1454 		*commit = NULL;
1455 	}
1456 	return err;
1457 }
1458 
1459 const struct got_error *
1460 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1461 {
1462 	const struct got_error *err = NULL;
1463 	struct imsg imsg;
1464 	size_t datalen;
1465 	const size_t min_datalen =
1466 	    MIN(sizeof(struct got_imsg_error),
1467 	    sizeof(struct got_imsg_commit_object));
1468 
1469 	*commit = NULL;
1470 
1471 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1472 	if (err)
1473 		return err;
1474 
1475 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1476 
1477 	switch (imsg.hdr.type) {
1478 	case GOT_IMSG_COMMIT:
1479 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1480 		break;
1481 	default:
1482 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1483 		break;
1484 	}
1485 
1486 	imsg_free(&imsg);
1487 
1488 	return err;
1489 }
1490 
1491 static const struct got_error *
1492 send_tree_entries(struct imsgbuf *ibuf, struct got_parsed_tree_entry *entries,
1493     int idx0, int idxN, size_t len)
1494 {
1495 	static const struct got_error *err;
1496 	struct ibuf *wbuf;
1497 	struct got_imsg_tree_entries ientries;
1498 	int i;
1499 
1500 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRIES, 0, 0, len);
1501 	if (wbuf == NULL)
1502 		return got_error_from_errno("imsg_create TREE_ENTRY");
1503 
1504 	ientries.nentries = idxN - idx0 + 1;
1505 	if (imsg_add(wbuf, &ientries, sizeof(ientries)) == -1) {
1506 		err = got_error_from_errno("imsg_add TREE_ENTRY");
1507 		ibuf_free(wbuf);
1508 		return err;
1509 	}
1510 
1511 	for (i = idx0; i <= idxN; i++) {
1512 		struct got_parsed_tree_entry *pte = &entries[i];
1513 
1514 		/* Keep in sync with struct got_imsg_tree_object definition! */
1515 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1) {
1516 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1517 			ibuf_free(wbuf);
1518 			return err;
1519 		}
1520 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1) {
1521 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1522 			ibuf_free(wbuf);
1523 			return err;
1524 		}
1525 		if (imsg_add(wbuf, &pte->namelen, sizeof(pte->namelen)) == -1) {
1526 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1527 			ibuf_free(wbuf);
1528 			return err;
1529 		}
1530 		
1531 		/* Remaining bytes are the entry's name. */
1532 		if (imsg_add(wbuf, pte->name, pte->namelen) == -1) {
1533 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1534 			ibuf_free(wbuf);
1535 			return err;
1536 		}
1537 	}
1538 
1539 	wbuf->fd = -1;
1540 	imsg_close(ibuf, wbuf);
1541 	return NULL;
1542 }
1543 
1544 const struct got_error *
1545 got_privsep_send_tree(struct imsgbuf *ibuf,
1546     struct got_parsed_tree_entry *entries, int nentries)
1547 {
1548 	const struct got_error *err = NULL;
1549 	struct got_imsg_tree_object itree;
1550 	size_t entries_len;
1551 	int i, j;
1552 
1553 	itree.nentries = nentries;
1554 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1555 	    == -1)
1556 		return got_error_from_errno("imsg_compose TREE");
1557 
1558 	entries_len = sizeof(struct got_imsg_tree_entries);
1559 	i = 0;
1560 	for (j = 0; j < nentries; j++) {
1561 		struct got_parsed_tree_entry *pte = &entries[j];
1562 		size_t len = sizeof(*pte) + pte->namelen;
1563 
1564 		if (j > 0 &&
1565 		    entries_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1566 			err = send_tree_entries(ibuf, entries,
1567 			    i, j - 1, entries_len);
1568 			if (err)
1569 				return err;
1570 			i = j;
1571 			entries_len = sizeof(struct got_imsg_tree_entries);
1572 		}
1573 
1574 		entries_len += len;
1575 	}
1576 
1577 	if (j > 0) {
1578 		err = send_tree_entries(ibuf, entries, i, j - 1, entries_len);
1579 		if (err)
1580 			return err;
1581 	}
1582 
1583 	return flush_imsg(ibuf);
1584 }
1585 
1586 const struct got_error *
1587 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1588 {
1589 	const struct got_error *err = NULL;
1590 	const size_t min_datalen =
1591 	    MIN(sizeof(struct got_imsg_error),
1592 	    sizeof(struct got_imsg_tree_object));
1593 	struct got_imsg_tree_object *itree;
1594 	size_t i;
1595 	int nentries = 0;
1596 
1597 	*tree = NULL;
1598 
1599 	err = read_imsg(ibuf);
1600 	if (err)
1601 		goto done;
1602 
1603 	for (;;) {
1604 		struct imsg imsg;
1605 		size_t n;
1606 		size_t datalen;
1607 		struct got_imsg_tree_entries *ientries;
1608 		struct got_tree_entry *te = NULL;
1609 		size_t te_offset;
1610 
1611 		n = imsg_get(ibuf, &imsg);
1612 		if (n == 0) {
1613 			if ((*tree)) {
1614 				if (nentries < (*tree)->nentries) {
1615 					err = read_imsg(ibuf);
1616 					if (err)
1617 						break;
1618 					continue;
1619 				} else
1620 					break;
1621 			} else {
1622 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1623 				break;
1624 			}
1625 		}
1626 
1627 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen) {
1628 			imsg_free(&imsg);
1629 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1630 			break;
1631 		}
1632 
1633 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1634 
1635 		switch (imsg.hdr.type) {
1636 		case GOT_IMSG_ERROR:
1637 			err = recv_imsg_error(&imsg, datalen);
1638 			break;
1639 		case GOT_IMSG_TREE:
1640 			/* This message should only appear once. */
1641 			if (*tree != NULL) {
1642 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1643 				break;
1644 			}
1645 			if (datalen != sizeof(*itree)) {
1646 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1647 				break;
1648 			}
1649 			itree = imsg.data;
1650 			if (itree->nentries < 0) {
1651 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1652 				break;
1653 			}
1654 			*tree = malloc(sizeof(**tree));
1655 			if (*tree == NULL) {
1656 				err = got_error_from_errno("malloc");
1657 				break;
1658 			}
1659 			(*tree)->entries = calloc(itree->nentries,
1660 			    sizeof(struct got_tree_entry));
1661 			if ((*tree)->entries == NULL) {
1662 				err = got_error_from_errno("malloc");
1663 				free(*tree);
1664 				*tree = NULL;
1665 				break;
1666 			}
1667 			(*tree)->nentries = itree->nentries;
1668 			(*tree)->refcnt = 0;
1669 			break;
1670 		case GOT_IMSG_TREE_ENTRIES:
1671 			/* This message should be preceeded by GOT_IMSG_TREE. */
1672 			if (*tree == NULL) {
1673 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1674 				break;
1675 			}
1676 			if (datalen <= sizeof(*ientries) ||
1677 			    datalen > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1678 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1679 				break;
1680 			}
1681 
1682 			ientries = imsg.data;
1683 			if (ientries->nentries > INT_MAX) {
1684 				err = got_error_msg(GOT_ERR_NO_SPACE,
1685 				    "too many tree entries");
1686 				break;
1687 			}
1688 			te_offset = sizeof(*ientries);
1689 			for (i = 0; i < ientries->nentries; i++) {
1690 				struct got_imsg_tree_entry ite;
1691 				const char *te_name;
1692 				uint8_t *buf = imsg.data + te_offset;
1693 
1694 				if (te_offset >= datalen) {
1695 					err = got_error(GOT_ERR_PRIVSEP_LEN);
1696 					break;
1697 				}
1698 
1699 				/* Might not be aligned, size is ~32 bytes. */
1700 				memcpy(&ite, buf, sizeof(ite));
1701 
1702 				if (ite.namelen >= sizeof(te->name)) {
1703 					err = got_error(GOT_ERR_PRIVSEP_LEN);
1704 					break;
1705 				}
1706 				if (te_offset + sizeof(ite) + ite.namelen >
1707 				    datalen) {
1708 					err = got_error(GOT_ERR_PRIVSEP_LEN);
1709 					break;
1710 				}
1711 				if (nentries >= (*tree)->nentries) {
1712 					err = got_error(GOT_ERR_PRIVSEP_LEN);
1713 					break;
1714 				}
1715 				te = &(*tree)->entries[nentries];
1716 				te_name = buf + sizeof(ite);
1717 				memcpy(te->name, te_name, ite.namelen);
1718 				te->name[ite.namelen] = '\0';
1719 				memcpy(te->id.sha1, ite.id, SHA1_DIGEST_LENGTH);
1720 				te->mode = ite.mode;
1721 				te->idx = nentries;
1722 				nentries++;
1723 
1724 				te_offset += sizeof(ite) + ite.namelen;
1725 			}
1726 			break;
1727 		default:
1728 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1729 			break;
1730 		}
1731 
1732 		imsg_free(&imsg);
1733 		if (err)
1734 			break;
1735 	}
1736 done:
1737 	if (*tree && (*tree)->nentries != nentries) {
1738 		if (err == NULL)
1739 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1740 		got_object_tree_close(*tree);
1741 		*tree = NULL;
1742 	}
1743 
1744 	return err;
1745 }
1746 
1747 const struct got_error *
1748 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1749     const uint8_t *data)
1750 {
1751 	struct got_imsg_blob iblob;
1752 
1753 	iblob.size = size;
1754 	iblob.hdrlen = hdrlen;
1755 
1756 	if (data) {
1757 		uint8_t *buf;
1758 
1759 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1760 			return got_error(GOT_ERR_NO_SPACE);
1761 
1762 		buf = malloc(sizeof(iblob) + size);
1763 		if (buf == NULL)
1764 			return got_error_from_errno("malloc");
1765 
1766 		memcpy(buf, &iblob, sizeof(iblob));
1767 		memcpy(buf + sizeof(iblob), data, size);
1768 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1769 		    sizeof(iblob) + size) == -1) {
1770 			free(buf);
1771 			return got_error_from_errno("imsg_compose BLOB");
1772 		}
1773 		free(buf);
1774 	} else {
1775 		/* Data has already been written to file descriptor. */
1776 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1777 		    sizeof(iblob)) == -1)
1778 			return got_error_from_errno("imsg_compose BLOB");
1779 	}
1780 
1781 
1782 	return flush_imsg(ibuf);
1783 }
1784 
1785 const struct got_error *
1786 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1787     struct imsgbuf *ibuf)
1788 {
1789 	const struct got_error *err = NULL;
1790 	struct imsg imsg;
1791 	struct got_imsg_blob *iblob;
1792 	size_t datalen;
1793 
1794 	*outbuf = NULL;
1795 
1796 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1797 	if (err)
1798 		return err;
1799 
1800 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1801 
1802 	switch (imsg.hdr.type) {
1803 	case GOT_IMSG_BLOB:
1804 		if (datalen < sizeof(*iblob)) {
1805 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1806 			break;
1807 		}
1808 		iblob = imsg.data;
1809 		*size = iblob->size;
1810 		*hdrlen = iblob->hdrlen;
1811 
1812 		if (datalen == sizeof(*iblob)) {
1813 			/* Data has been written to file descriptor. */
1814 			break;
1815 		}
1816 
1817 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX) {
1818 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1819 			break;
1820 		}
1821 
1822 		*outbuf = malloc(*size);
1823 		if (*outbuf == NULL) {
1824 			err = got_error_from_errno("malloc");
1825 			break;
1826 		}
1827 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1828 		break;
1829 	default:
1830 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1831 		break;
1832 	}
1833 
1834 	imsg_free(&imsg);
1835 
1836 	return err;
1837 }
1838 
1839 static const struct got_error *
1840 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1841 {
1842 	const struct got_error *err = NULL;
1843 	size_t offset, remain;
1844 
1845 	offset = 0;
1846 	remain = tagmsg_len;
1847 	while (remain > 0) {
1848 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1849 
1850 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1851 		    tag->tagmsg + offset, n) == -1) {
1852 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1853 			break;
1854 		}
1855 
1856 		err = flush_imsg(ibuf);
1857 		if (err)
1858 			break;
1859 
1860 		offset += n;
1861 		remain -= n;
1862 	}
1863 
1864 	return err;
1865 }
1866 
1867 const struct got_error *
1868 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1869 {
1870 	const struct got_error *err = NULL;
1871 	struct got_imsg_tag_object *itag;
1872 	uint8_t *buf;
1873 	size_t len, total;
1874 	size_t tag_len = strlen(tag->tag);
1875 	size_t tagger_len = strlen(tag->tagger);
1876 	size_t tagmsg_len = strlen(tag->tagmsg);
1877 
1878 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1879 
1880 	buf = malloc(total);
1881 	if (buf == NULL)
1882 		return got_error_from_errno("malloc");
1883 
1884 	itag = (struct got_imsg_tag_object *)buf;
1885 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1886 	itag->obj_type = tag->obj_type;
1887 	itag->tag_len = tag_len;
1888 	itag->tagger_len = tagger_len;
1889 	itag->tagger_time = tag->tagger_time;
1890 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1891 	itag->tagmsg_len = tagmsg_len;
1892 
1893 	len = sizeof(*itag);
1894 	memcpy(buf + len, tag->tag, tag_len);
1895 	len += tag_len;
1896 	memcpy(buf + len, tag->tagger, tagger_len);
1897 	len += tagger_len;
1898 
1899 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1900 		err = got_error_from_errno("imsg_compose TAG");
1901 		goto done;
1902 	}
1903 
1904 	if (tagmsg_len == 0 ||
1905 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1906 		err = flush_imsg(ibuf);
1907 		if (err)
1908 			goto done;
1909 	}
1910 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1911 done:
1912 	free(buf);
1913 	return err;
1914 }
1915 
1916 const struct got_error *
1917 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1918 {
1919 	const struct got_error *err = NULL;
1920 	struct imsg imsg;
1921 	struct got_imsg_tag_object *itag;
1922 	size_t len, datalen;
1923 	const size_t min_datalen =
1924 	    MIN(sizeof(struct got_imsg_error),
1925 	    sizeof(struct got_imsg_tag_object));
1926 
1927 	*tag = NULL;
1928 
1929 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1930 	if (err)
1931 		return err;
1932 
1933 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1934 	len = 0;
1935 
1936 	switch (imsg.hdr.type) {
1937 	case GOT_IMSG_TAG:
1938 		if (datalen < sizeof(*itag)) {
1939 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1940 			break;
1941 		}
1942 		itag = imsg.data;
1943 		if (datalen != sizeof(*itag) + itag->tag_len +
1944 		    itag->tagger_len) {
1945 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1946 			break;
1947 		}
1948 		len += sizeof(*itag);
1949 
1950 		*tag = calloc(1, sizeof(**tag));
1951 		if (*tag == NULL) {
1952 			err = got_error_from_errno("calloc");
1953 			break;
1954 		}
1955 
1956 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1957 
1958 		if (itag->tag_len == 0) {
1959 			(*tag)->tag = strdup("");
1960 			if ((*tag)->tag == NULL) {
1961 				err = got_error_from_errno("strdup");
1962 				break;
1963 			}
1964 		} else {
1965 			(*tag)->tag = malloc(itag->tag_len + 1);
1966 			if ((*tag)->tag == NULL) {
1967 				err = got_error_from_errno("malloc");
1968 				break;
1969 			}
1970 			memcpy((*tag)->tag, imsg.data + len,
1971 			    itag->tag_len);
1972 			(*tag)->tag[itag->tag_len] = '\0';
1973 		}
1974 		len += itag->tag_len;
1975 
1976 		(*tag)->obj_type = itag->obj_type;
1977 		(*tag)->tagger_time = itag->tagger_time;
1978 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1979 
1980 		if (itag->tagger_len == 0) {
1981 			(*tag)->tagger = strdup("");
1982 			if ((*tag)->tagger == NULL) {
1983 				err = got_error_from_errno("strdup");
1984 				break;
1985 			}
1986 		} else {
1987 			(*tag)->tagger = malloc(itag->tagger_len + 1);
1988 			if ((*tag)->tagger == NULL) {
1989 				err = got_error_from_errno("malloc");
1990 				break;
1991 			}
1992 			memcpy((*tag)->tagger, imsg.data + len,
1993 			    itag->tagger_len);
1994 			(*tag)->tagger[itag->tagger_len] = '\0';
1995 		}
1996 		len += itag->tagger_len;
1997 
1998 		if (itag->tagmsg_len == 0) {
1999 			(*tag)->tagmsg = strdup("");
2000 			if ((*tag)->tagmsg == NULL) {
2001 				err = got_error_from_errno("strdup");
2002 				break;
2003 			}
2004 		} else {
2005 			size_t offset = 0, remain = itag->tagmsg_len;
2006 
2007 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
2008 			if ((*tag)->tagmsg == NULL) {
2009 				err = got_error_from_errno("malloc");
2010 				break;
2011 			}
2012 			while (remain > 0) {
2013 				struct imsg imsg_log;
2014 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
2015 				    remain);
2016 
2017 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
2018 				if (err)
2019 					return err;
2020 
2021 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
2022 					return got_error(GOT_ERR_PRIVSEP_MSG);
2023 
2024 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
2025 				    n);
2026 				imsg_free(&imsg_log);
2027 				offset += n;
2028 				remain -= n;
2029 			}
2030 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
2031 		}
2032 
2033 		break;
2034 	default:
2035 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2036 		break;
2037 	}
2038 
2039 	imsg_free(&imsg);
2040 
2041 	return err;
2042 }
2043 
2044 const struct got_error *
2045 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
2046     struct got_packidx *packidx)
2047 {
2048 	const struct got_error *err = NULL;
2049 	struct got_imsg_packidx ipackidx;
2050 	struct got_imsg_pack ipack;
2051 	int fd;
2052 
2053 	ipackidx.len = packidx->len;
2054 	ipackidx.packfile_size = pack->filesize;
2055 	fd = dup(packidx->fd);
2056 	if (fd == -1)
2057 		return got_error_from_errno("dup");
2058 
2059 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
2060 	    sizeof(ipackidx)) == -1) {
2061 		err = got_error_from_errno("imsg_compose PACKIDX");
2062 		close(fd);
2063 		return err;
2064 	}
2065 
2066 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
2067 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
2068 		return got_error(GOT_ERR_NO_SPACE);
2069 	ipack.filesize = pack->filesize;
2070 
2071 	fd = dup(pack->fd);
2072 	if (fd == -1)
2073 		return got_error_from_errno("dup");
2074 
2075 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
2076 	    == -1) {
2077 		err = got_error_from_errno("imsg_compose PACK");
2078 		close(fd);
2079 		return err;
2080 	}
2081 
2082 	return flush_imsg(ibuf);
2083 }
2084 
2085 const struct got_error *
2086 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
2087     struct got_object_id *id)
2088 {
2089 	struct got_imsg_packed_object iobj;
2090 
2091 	iobj.idx = idx;
2092 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2093 
2094 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
2095 	    &iobj, sizeof(iobj)) == -1)
2096 		return got_error_from_errno("imsg_compose "
2097 		    "PACKED_OBJECT_REQUEST");
2098 
2099 	return flush_imsg(ibuf);
2100 }
2101 
2102 const struct got_error *
2103 got_privsep_send_packed_raw_obj_req(struct imsgbuf *ibuf, int idx,
2104     struct got_object_id *id)
2105 {
2106 	struct got_imsg_packed_object iobj;
2107 
2108 	iobj.idx = idx;
2109 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
2110 
2111 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_RAW_OBJECT_REQUEST, 0, 0, -1,
2112 	    &iobj, sizeof(iobj)) == -1)
2113 		return got_error_from_errno("imsg_compose "
2114 		    "PACKED_OBJECT_REQUEST");
2115 
2116 	return flush_imsg(ibuf);
2117 }
2118 
2119 const struct got_error *
2120 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
2121 {
2122 	const struct got_error *err = NULL;
2123 
2124 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
2125 	    NULL, 0) == -1) {
2126 		err = got_error_from_errno("imsg_compose "
2127 		    "GITCONFIG_PARSE_REQUEST");
2128 		close(fd);
2129 		return err;
2130 	}
2131 
2132 	return flush_imsg(ibuf);
2133 }
2134 
2135 const struct got_error *
2136 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
2137 {
2138 	if (imsg_compose(ibuf,
2139 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
2140 	    NULL, 0) == -1)
2141 		return got_error_from_errno("imsg_compose "
2142 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
2143 
2144 	return flush_imsg(ibuf);
2145 }
2146 
2147 const struct got_error *
2148 got_privsep_send_gitconfig_repository_extensions_req(struct imsgbuf *ibuf)
2149 {
2150 	if (imsg_compose(ibuf,
2151 	    GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST, 0, 0, -1,
2152 	    NULL, 0) == -1)
2153 		return got_error_from_errno("imsg_compose "
2154 		    "GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST");
2155 
2156 	return flush_imsg(ibuf);
2157 }
2158 
2159 
2160 const struct got_error *
2161 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
2162 {
2163 	if (imsg_compose(ibuf,
2164 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
2165 		return got_error_from_errno("imsg_compose "
2166 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
2167 
2168 	return flush_imsg(ibuf);
2169 }
2170 
2171 const struct got_error *
2172 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
2173 {
2174 	if (imsg_compose(ibuf,
2175 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
2176 		return got_error_from_errno("imsg_compose "
2177 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
2178 
2179 	return flush_imsg(ibuf);
2180 }
2181 
2182 const struct got_error *
2183 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
2184 {
2185 	if (imsg_compose(ibuf,
2186 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2187 		return got_error_from_errno("imsg_compose "
2188 		    "GITCONFIG_REMOTE_REQUEST");
2189 
2190 	return flush_imsg(ibuf);
2191 }
2192 
2193 const struct got_error *
2194 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
2195 {
2196 	if (imsg_compose(ibuf,
2197 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
2198 		return got_error_from_errno("imsg_compose "
2199 		    "GITCONFIG_OWNER_REQUEST");
2200 
2201 	return flush_imsg(ibuf);
2202 }
2203 
2204 const struct got_error *
2205 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
2206 {
2207 	const struct got_error *err = NULL;
2208 	struct imsg imsg;
2209 	size_t datalen;
2210 	const size_t min_datalen = 0;
2211 
2212 	*str = NULL;
2213 
2214 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2215 	if (err)
2216 		return err;
2217 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2218 
2219 	switch (imsg.hdr.type) {
2220 	case GOT_IMSG_GITCONFIG_STR_VAL:
2221 		if (datalen == 0)
2222 			break;
2223 		/* datalen does not include terminating \0 */
2224 		*str = malloc(datalen + 1);
2225 		if (*str == NULL) {
2226 			err = got_error_from_errno("malloc");
2227 			break;
2228 		}
2229 		memcpy(*str, imsg.data, datalen);
2230 		(*str)[datalen] = '\0';
2231 		break;
2232 	default:
2233 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2234 		break;
2235 	}
2236 
2237 	imsg_free(&imsg);
2238 	return err;
2239 }
2240 
2241 const struct got_error *
2242 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
2243 {
2244 	const struct got_error *err = NULL;
2245 	struct imsg imsg;
2246 	size_t datalen;
2247 	const size_t min_datalen =
2248 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
2249 
2250 	*val = 0;
2251 
2252 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2253 	if (err)
2254 		return err;
2255 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2256 
2257 	switch (imsg.hdr.type) {
2258 	case GOT_IMSG_GITCONFIG_INT_VAL:
2259 		if (datalen != sizeof(*val)) {
2260 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2261 			break;
2262 		}
2263 		memcpy(val, imsg.data, sizeof(*val));
2264 		break;
2265 	default:
2266 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2267 		break;
2268 	}
2269 
2270 	imsg_free(&imsg);
2271 	return err;
2272 }
2273 
2274 static void
2275 free_remote_data(struct got_remote_repo *remote)
2276 {
2277 	int i;
2278 
2279 	free(remote->name);
2280 	free(remote->fetch_url);
2281 	free(remote->send_url);
2282 	for (i = 0; i < remote->nfetch_branches; i++)
2283 		free(remote->fetch_branches[i]);
2284 	free(remote->fetch_branches);
2285 	for (i = 0; i < remote->nsend_branches; i++)
2286 		free(remote->send_branches[i]);
2287 	free(remote->send_branches);
2288 	for (i = 0; i < remote->nfetch_refs; i++)
2289 		free(remote->fetch_refs[i]);
2290 	free(remote->fetch_refs);
2291 }
2292 
2293 const struct got_error *
2294 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
2295     int *nremotes, struct imsgbuf *ibuf)
2296 {
2297 	const struct got_error *err = NULL;
2298 	struct imsg imsg;
2299 	size_t datalen;
2300 	struct got_imsg_remotes iremotes;
2301 	struct got_imsg_remote iremote;
2302 
2303 	*remotes = NULL;
2304 	*nremotes = 0;
2305 	iremotes.nremotes = 0;
2306 
2307 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
2308 	if (err)
2309 		return err;
2310 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2311 
2312 	switch (imsg.hdr.type) {
2313 	case GOT_IMSG_GITCONFIG_REMOTES:
2314 		if (datalen != sizeof(iremotes)) {
2315 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2316 			break;
2317 		}
2318 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2319 		if (iremotes.nremotes == 0) {
2320 			imsg_free(&imsg);
2321 			return NULL;
2322 		}
2323 		break;
2324 	default:
2325 		imsg_free(&imsg);
2326 		return got_error(GOT_ERR_PRIVSEP_MSG);
2327 	}
2328 
2329 	imsg_free(&imsg);
2330 
2331 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2332 	if (*remotes == NULL)
2333 		return got_error_from_errno("recallocarray");
2334 
2335 	while (*nremotes < iremotes.nremotes) {
2336 		struct got_remote_repo *remote;
2337 
2338 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
2339 		if (err)
2340 			break;
2341 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2342 
2343 		switch (imsg.hdr.type) {
2344 		case GOT_IMSG_GITCONFIG_REMOTE:
2345 			remote = &(*remotes)[*nremotes];
2346 			memset(remote, 0, sizeof(*remote));
2347 			if (datalen < sizeof(iremote)) {
2348 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2349 				break;
2350 			}
2351 			memcpy(&iremote, imsg.data, sizeof(iremote));
2352 			if (iremote.name_len == 0 ||
2353 			    iremote.fetch_url_len == 0 ||
2354 			    iremote.send_url_len == 0 ||
2355 			    (sizeof(iremote) + iremote.name_len +
2356 			    iremote.fetch_url_len + iremote.send_url_len) > datalen) {
2357 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2358 				break;
2359 			}
2360 			remote->name = strndup(imsg.data + sizeof(iremote),
2361 			    iremote.name_len);
2362 			if (remote->name == NULL) {
2363 				err = got_error_from_errno("strndup");
2364 				break;
2365 			}
2366 			remote->fetch_url = strndup(imsg.data + sizeof(iremote) +
2367 			    iremote.name_len, iremote.fetch_url_len);
2368 			if (remote->fetch_url == NULL) {
2369 				err = got_error_from_errno("strndup");
2370 				free_remote_data(remote);
2371 				break;
2372 			}
2373 			remote->send_url = strndup(imsg.data + sizeof(iremote) +
2374 			    iremote.name_len + iremote.fetch_url_len,
2375 			    iremote.send_url_len);
2376 			if (remote->send_url == NULL) {
2377 				err = got_error_from_errno("strndup");
2378 				free_remote_data(remote);
2379 				break;
2380 			}
2381 			remote->mirror_references = iremote.mirror_references;
2382 			remote->fetch_all_branches = iremote.fetch_all_branches;
2383 			remote->nfetch_branches = 0;
2384 			remote->fetch_branches = NULL;
2385 			remote->nsend_branches = 0;
2386 			remote->send_branches = NULL;
2387 			remote->nfetch_refs = 0;
2388 			remote->fetch_refs = NULL;
2389 			(*nremotes)++;
2390 			break;
2391 		default:
2392 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2393 			break;
2394 		}
2395 
2396 		imsg_free(&imsg);
2397 		if (err)
2398 			break;
2399 	}
2400 
2401 	if (err) {
2402 		int i;
2403 		for (i = 0; i < *nremotes; i++)
2404 			free_remote_data(&(*remotes)[i]);
2405 		free(*remotes);
2406 		*remotes = NULL;
2407 		*nremotes = 0;
2408 	}
2409 	return err;
2410 }
2411 
2412 const struct got_error *
2413 got_privsep_send_gotconfig_parse_req(struct imsgbuf *ibuf, int fd)
2414 {
2415 	const struct got_error *err = NULL;
2416 
2417 	if (imsg_compose(ibuf, GOT_IMSG_GOTCONFIG_PARSE_REQUEST, 0, 0, fd,
2418 	    NULL, 0) == -1) {
2419 		err = got_error_from_errno("imsg_compose "
2420 		    "GOTCONFIG_PARSE_REQUEST");
2421 		close(fd);
2422 		return err;
2423 	}
2424 
2425 	return flush_imsg(ibuf);
2426 }
2427 
2428 const struct got_error *
2429 got_privsep_send_gotconfig_author_req(struct imsgbuf *ibuf)
2430 {
2431 	if (imsg_compose(ibuf,
2432 	    GOT_IMSG_GOTCONFIG_AUTHOR_REQUEST, 0, 0, -1, NULL, 0) == -1)
2433 		return got_error_from_errno("imsg_compose "
2434 		    "GOTCONFIG_AUTHOR_REQUEST");
2435 
2436 	return flush_imsg(ibuf);
2437 }
2438 
2439 const struct got_error *
2440 got_privsep_send_gotconfig_remotes_req(struct imsgbuf *ibuf)
2441 {
2442 	if (imsg_compose(ibuf,
2443 	    GOT_IMSG_GOTCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2444 		return got_error_from_errno("imsg_compose "
2445 		    "GOTCONFIG_REMOTE_REQUEST");
2446 
2447 	return flush_imsg(ibuf);
2448 }
2449 
2450 const struct got_error *
2451 got_privsep_recv_gotconfig_str(char **str, struct imsgbuf *ibuf)
2452 {
2453 	const struct got_error *err = NULL;
2454 	struct imsg imsg;
2455 	size_t datalen;
2456 	const size_t min_datalen = 0;
2457 
2458 	*str = NULL;
2459 
2460 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2461 	if (err)
2462 		return err;
2463 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2464 
2465 	switch (imsg.hdr.type) {
2466 	case GOT_IMSG_ERROR:
2467 		if (datalen < sizeof(struct got_imsg_error)) {
2468 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2469 			break;
2470 		}
2471 		err = recv_imsg_error(&imsg, datalen);
2472 		break;
2473 	case GOT_IMSG_GOTCONFIG_STR_VAL:
2474 		if (datalen == 0)
2475 			break;
2476 		/* datalen does not include terminating \0 */
2477 		*str = malloc(datalen + 1);
2478 		if (*str == NULL) {
2479 			err = got_error_from_errno("malloc");
2480 			break;
2481 		}
2482 		memcpy(*str, imsg.data, datalen);
2483 		(*str)[datalen] = '\0';
2484 		break;
2485 	default:
2486 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2487 		break;
2488 	}
2489 
2490 	imsg_free(&imsg);
2491 	return err;
2492 }
2493 
2494 const struct got_error *
2495 got_privsep_recv_gotconfig_remotes(struct got_remote_repo **remotes,
2496     int *nremotes, struct imsgbuf *ibuf)
2497 {
2498 	const struct got_error *err = NULL;
2499 	struct imsg imsg;
2500 	size_t datalen;
2501 	struct got_imsg_remotes iremotes;
2502 	struct got_imsg_remote iremote;
2503 	const size_t min_datalen =
2504 	    MIN(sizeof(struct got_imsg_error), sizeof(iremotes));
2505 
2506 	*remotes = NULL;
2507 	*nremotes = 0;
2508 	iremotes.nremotes = 0;
2509 
2510 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2511 	if (err)
2512 		return err;
2513 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2514 
2515 	switch (imsg.hdr.type) {
2516 	case GOT_IMSG_ERROR:
2517 		if (datalen < sizeof(struct got_imsg_error)) {
2518 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2519 			break;
2520 		}
2521 		err = recv_imsg_error(&imsg, datalen);
2522 		break;
2523 	case GOT_IMSG_GOTCONFIG_REMOTES:
2524 		if (datalen != sizeof(iremotes)) {
2525 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2526 			break;
2527 		}
2528 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2529 		if (iremotes.nremotes == 0) {
2530 			imsg_free(&imsg);
2531 			return NULL;
2532 		}
2533 		break;
2534 	default:
2535 		imsg_free(&imsg);
2536 		return got_error(GOT_ERR_PRIVSEP_MSG);
2537 	}
2538 
2539 	imsg_free(&imsg);
2540 
2541 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2542 	if (*remotes == NULL)
2543 		return got_error_from_errno("recallocarray");
2544 
2545 	while (*nremotes < iremotes.nremotes) {
2546 		struct got_remote_repo *remote;
2547 		const size_t min_datalen =
2548 		    MIN(sizeof(struct got_imsg_error), sizeof(iremote));
2549 		int i;
2550 
2551 		err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2552 		if (err)
2553 			break;
2554 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2555 
2556 		switch (imsg.hdr.type) {
2557 		case GOT_IMSG_ERROR:
2558 			if (datalen < sizeof(struct got_imsg_error)) {
2559 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2560 				break;
2561 			}
2562 			err = recv_imsg_error(&imsg, datalen);
2563 			break;
2564 		case GOT_IMSG_GOTCONFIG_REMOTE:
2565 			remote = &(*remotes)[*nremotes];
2566 			memset(remote, 0, sizeof(*remote));
2567 			if (datalen < sizeof(iremote)) {
2568 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2569 				break;
2570 			}
2571 			memcpy(&iremote, imsg.data, sizeof(iremote));
2572 			if (iremote.name_len == 0 ||
2573 			    (iremote.fetch_url_len == 0 &&
2574 			    iremote.send_url_len == 0) ||
2575 			    (sizeof(iremote) + iremote.name_len +
2576 			    iremote.fetch_url_len + iremote.send_url_len) >
2577 			    datalen) {
2578 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2579 				break;
2580 			}
2581 			remote->name = strndup(imsg.data + sizeof(iremote),
2582 			    iremote.name_len);
2583 			if (remote->name == NULL) {
2584 				err = got_error_from_errno("strndup");
2585 				break;
2586 			}
2587 			remote->fetch_url = strndup(imsg.data +
2588 			    sizeof(iremote) + iremote.name_len,
2589 			    iremote.fetch_url_len);
2590 			if (remote->fetch_url == NULL) {
2591 				err = got_error_from_errno("strndup");
2592 				free_remote_data(remote);
2593 				break;
2594 			}
2595 			remote->send_url = strndup(imsg.data +
2596 			    sizeof(iremote) + iremote.name_len +
2597 			    iremote.fetch_url_len, iremote.send_url_len);
2598 			if (remote->send_url == NULL) {
2599 				err = got_error_from_errno("strndup");
2600 				free_remote_data(remote);
2601 				break;
2602 			}
2603 			remote->mirror_references = iremote.mirror_references;
2604 			remote->fetch_all_branches = iremote.fetch_all_branches;
2605 			if (iremote.nfetch_branches > 0) {
2606 				remote->fetch_branches = recallocarray(NULL, 0,
2607 				    iremote.nfetch_branches, sizeof(char *));
2608 				if (remote->fetch_branches == NULL) {
2609 					err = got_error_from_errno("calloc");
2610 					free_remote_data(remote);
2611 					break;
2612 				}
2613 			}
2614 			remote->nfetch_branches = 0;
2615 			for (i = 0; i < iremote.nfetch_branches; i++) {
2616 				char *branch;
2617 				err = got_privsep_recv_gotconfig_str(&branch,
2618 				    ibuf);
2619 				if (err) {
2620 					free_remote_data(remote);
2621 					goto done;
2622 				}
2623 				remote->fetch_branches[i] = branch;
2624 				remote->nfetch_branches++;
2625 			}
2626 			if (iremote.nsend_branches > 0) {
2627 				remote->send_branches = recallocarray(NULL, 0,
2628 				    iremote.nsend_branches, sizeof(char *));
2629 				if (remote->send_branches == NULL) {
2630 					err = got_error_from_errno("calloc");
2631 					free_remote_data(remote);
2632 					break;
2633 				}
2634 			}
2635 			remote->nsend_branches = 0;
2636 			for (i = 0; i < iremote.nsend_branches; i++) {
2637 				char *branch;
2638 				err = got_privsep_recv_gotconfig_str(&branch,
2639 				    ibuf);
2640 				if (err) {
2641 					free_remote_data(remote);
2642 					goto done;
2643 				}
2644 				remote->send_branches[i] = branch;
2645 				remote->nsend_branches++;
2646 			}
2647 			if (iremote.nfetch_refs > 0) {
2648 				remote->fetch_refs = recallocarray(NULL, 0,
2649 				    iremote.nfetch_refs, sizeof(char *));
2650 				if (remote->fetch_refs == NULL) {
2651 					err = got_error_from_errno("calloc");
2652 					free_remote_data(remote);
2653 					break;
2654 				}
2655 			}
2656 			remote->nfetch_refs = 0;
2657 			for (i = 0; i < iremote.nfetch_refs; i++) {
2658 				char *ref;
2659 				err = got_privsep_recv_gotconfig_str(&ref,
2660 				    ibuf);
2661 				if (err) {
2662 					free_remote_data(remote);
2663 					goto done;
2664 				}
2665 				remote->fetch_refs[i] = ref;
2666 				remote->nfetch_refs++;
2667 			}
2668 			(*nremotes)++;
2669 			break;
2670 		default:
2671 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2672 			break;
2673 		}
2674 
2675 		imsg_free(&imsg);
2676 		if (err)
2677 			break;
2678 	}
2679 done:
2680 	if (err) {
2681 		int i;
2682 		for (i = 0; i < *nremotes; i++)
2683 			free_remote_data(&(*remotes)[i]);
2684 		free(*remotes);
2685 		*remotes = NULL;
2686 		*nremotes = 0;
2687 	}
2688 	return err;
2689 }
2690 
2691 const struct got_error *
2692 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
2693     struct got_object_id *id, int idx, const char *path)
2694 {
2695 	const struct got_error *err = NULL;
2696 	struct ibuf *wbuf;
2697 	size_t path_len = strlen(path) + 1;
2698 
2699 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
2700 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
2701 	if (wbuf == NULL)
2702 		return got_error_from_errno(
2703 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
2704 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
2705 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2706 		ibuf_free(wbuf);
2707 		return err;
2708 	}
2709 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1) {
2710 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2711 		ibuf_free(wbuf);
2712 		return err;
2713 	}
2714 	if (imsg_add(wbuf, path, path_len) == -1) {
2715 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2716 		ibuf_free(wbuf);
2717 		return err;
2718 	}
2719 
2720 	wbuf->fd = -1;
2721 	imsg_close(ibuf, wbuf);
2722 
2723 	return flush_imsg(ibuf);
2724 }
2725 
2726 const struct got_error *
2727 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
2728     struct got_object_id **changed_commit_id,
2729     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
2730 {
2731 	const struct got_error *err = NULL;
2732 	struct imsg imsg;
2733 	struct got_imsg_traversed_commits *icommits;
2734 	size_t datalen;
2735 	int i, done = 0;
2736 
2737 	*changed_commit = NULL;
2738 	*changed_commit_id = NULL;
2739 
2740 	while (!done) {
2741 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2742 		if (err)
2743 			return err;
2744 
2745 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2746 		switch (imsg.hdr.type) {
2747 		case GOT_IMSG_TRAVERSED_COMMITS:
2748 			icommits = imsg.data;
2749 			if (datalen != sizeof(*icommits) +
2750 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
2751 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2752 				break;
2753 			}
2754 			for (i = 0; i < icommits->ncommits; i++) {
2755 				struct got_object_qid *qid;
2756 				uint8_t *sha1 = (uint8_t *)imsg.data +
2757 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
2758 				err = got_object_qid_alloc_partial(&qid);
2759 				if (err)
2760 					break;
2761 				memcpy(qid->id.sha1, sha1, SHA1_DIGEST_LENGTH);
2762 				STAILQ_INSERT_TAIL(commit_ids, qid, entry);
2763 
2764 				/* The last commit may contain a change. */
2765 				if (i == icommits->ncommits - 1) {
2766 					*changed_commit_id =
2767 					    got_object_id_dup(&qid->id);
2768 					if (*changed_commit_id == NULL) {
2769 						err = got_error_from_errno(
2770 						    "got_object_id_dup");
2771 						break;
2772 					}
2773 				}
2774 			}
2775 			break;
2776 		case GOT_IMSG_COMMIT:
2777 			if (*changed_commit_id == NULL) {
2778 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2779 				break;
2780 			}
2781 			err = get_commit_from_imsg(changed_commit, &imsg,
2782 			    datalen, ibuf);
2783 			break;
2784 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
2785 			done = 1;
2786 			break;
2787 		default:
2788 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2789 			break;
2790 		}
2791 
2792 		imsg_free(&imsg);
2793 		if (err)
2794 			break;
2795 	}
2796 
2797 	if (err)
2798 		got_object_id_queue_free(commit_ids);
2799 	return err;
2800 }
2801 
2802 const struct got_error *
2803 got_privsep_send_raw_delta_req(struct imsgbuf *ibuf, int idx,
2804     struct got_object_id *id)
2805 {
2806 	struct got_imsg_raw_delta_request dreq;
2807 
2808 	dreq.idx = idx;
2809 	memcpy(dreq.id, id->sha1, SHA1_DIGEST_LENGTH);
2810 
2811 	if (imsg_compose(ibuf, GOT_IMSG_RAW_DELTA_REQUEST, 0, 0, -1,
2812 	    &dreq, sizeof(dreq)) == -1)
2813 		return got_error_from_errno("imsg_compose RAW_DELTA_REQUEST");
2814 
2815 	return flush_imsg(ibuf);
2816 }
2817 
2818 const struct got_error *
2819 got_privsep_send_raw_delta_outfd(struct imsgbuf *ibuf, int fd)
2820 {
2821 	return send_fd(ibuf, GOT_IMSG_RAW_DELTA_OUTFD, fd);
2822 }
2823 
2824 const struct got_error *
2825 got_privsep_send_raw_delta(struct imsgbuf *ibuf, uint64_t base_size,
2826     uint64_t result_size,  off_t delta_size, off_t delta_compressed_size,
2827     off_t delta_offset, off_t delta_out_offset, struct got_object_id *base_id)
2828 {
2829 	struct got_imsg_raw_delta idelta;
2830 	int ret;
2831 
2832 	idelta.base_size = base_size;
2833 	idelta.result_size = result_size;
2834 	idelta.delta_size = delta_size;
2835 	idelta.delta_compressed_size = delta_compressed_size;
2836 	idelta.delta_offset = delta_offset;
2837 	idelta.delta_out_offset = delta_out_offset;
2838 	memcpy(idelta.base_id, base_id->sha1, SHA1_DIGEST_LENGTH);
2839 
2840 	ret = imsg_compose(ibuf, GOT_IMSG_RAW_DELTA, 0, 0, -1,
2841 	    &idelta, sizeof(idelta));
2842 	if (ret == -1)
2843 		return got_error_from_errno("imsg_compose RAW_DELTA");
2844 
2845 	return flush_imsg(ibuf);
2846 }
2847 
2848 const struct got_error *
2849 got_privsep_recv_raw_delta(uint64_t *base_size, uint64_t *result_size,
2850     off_t *delta_size, off_t *delta_compressed_size, off_t *delta_offset,
2851     off_t *delta_out_offset, struct got_object_id **base_id, struct imsgbuf *ibuf)
2852 {
2853 	const struct got_error *err = NULL;
2854 	struct imsg imsg;
2855 	struct got_imsg_raw_delta *delta;
2856 	size_t datalen;
2857 
2858 	*base_size = 0;
2859 	*result_size = 0;
2860 	*delta_size = 0;
2861 	*delta_compressed_size = 0;
2862 	*delta_offset = 0;
2863 	*delta_out_offset = 0;
2864 	*base_id = NULL;
2865 
2866 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2867 	if (err)
2868 		return err;
2869 
2870 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2871 
2872 	switch (imsg.hdr.type) {
2873 	case GOT_IMSG_RAW_DELTA:
2874 		if (datalen != sizeof(*delta)) {
2875 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2876 			break;
2877 		}
2878 		delta = imsg.data;
2879 		*base_size = delta->base_size;
2880 		*result_size = delta->result_size;
2881 		*delta_size = delta->delta_size;
2882 		*delta_compressed_size = delta->delta_compressed_size;
2883 		*delta_offset = delta->delta_offset;
2884 		*delta_out_offset = delta->delta_out_offset;
2885 		*base_id = calloc(1, sizeof(**base_id));
2886 		if (*base_id == NULL) {
2887 			err = got_error_from_errno("malloc");
2888 			break;
2889 		}
2890 		memcpy((*base_id)->sha1, delta->base_id, SHA1_DIGEST_LENGTH);
2891 		break;
2892 	default:
2893 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2894 		break;
2895 	}
2896 
2897 	imsg_free(&imsg);
2898 
2899 	if (err) {
2900 		free(*base_id);
2901 		*base_id = NULL;
2902 	}
2903 	return err;
2904 }
2905 
2906 const struct got_error *
2907 got_privsep_send_object_idlist(struct imsgbuf *ibuf,
2908     struct got_object_id **ids, size_t nids)
2909 {
2910 	const struct got_error *err = NULL;
2911 	struct got_imsg_object_idlist idlist;
2912 	struct ibuf *wbuf;
2913 	size_t i;
2914 
2915 	if (nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS)
2916 		return got_error(GOT_ERR_NO_SPACE);
2917 
2918 	wbuf = imsg_create(ibuf, GOT_IMSG_OBJ_ID_LIST, 0, 0,
2919 	    sizeof(idlist) + nids * sizeof(**ids));
2920 	if (wbuf == NULL) {
2921 		err = got_error_from_errno("imsg_create OBJ_ID_LIST");
2922 		return err;
2923 	}
2924 
2925 	idlist.nids = nids;
2926 	if (imsg_add(wbuf, &idlist, sizeof(idlist)) == -1) {
2927 		err = got_error_from_errno("imsg_add OBJ_ID_LIST");
2928 		ibuf_free(wbuf);
2929 		return err;
2930 	}
2931 
2932 	for (i = 0; i < nids; i++) {
2933 		struct got_object_id *id = ids[i];
2934 		if (imsg_add(wbuf, id, sizeof(*id)) == -1) {
2935 			err = got_error_from_errno("imsg_add OBJ_ID_LIST");
2936 			ibuf_free(wbuf);
2937 			return err;
2938 		}
2939 	}
2940 	
2941 	wbuf->fd = -1;
2942 	imsg_close(ibuf, wbuf);
2943 
2944 	return flush_imsg(ibuf);
2945 }
2946 
2947 const struct got_error *
2948 got_privsep_send_object_idlist_done(struct imsgbuf *ibuf)
2949 {
2950 	if (imsg_compose(ibuf, GOT_IMSG_OBJ_ID_LIST_DONE, 0, 0, -1, NULL, 0)
2951 	    == -1)
2952 		return got_error_from_errno("imsg_compose OBJ_ID_LIST_DONE");
2953 
2954 	return flush_imsg(ibuf);
2955 }
2956 
2957 const struct got_error *
2958 got_privsep_recv_object_idlist(int *done, struct got_object_id **ids,
2959     size_t *nids, struct imsgbuf *ibuf)
2960 {
2961 	const struct got_error *err = NULL;
2962 	struct imsg imsg;
2963 	struct got_imsg_object_idlist *idlist;
2964 	size_t datalen;
2965 
2966 	*ids = NULL;
2967 	*done = 0;
2968 	*nids = 0;
2969 
2970 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2971 	if (err)
2972 		return err;
2973 
2974 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2975 	switch (imsg.hdr.type) {
2976 	case GOT_IMSG_OBJ_ID_LIST:
2977 		if (datalen < sizeof(*idlist)) {
2978 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2979 			break;
2980 		}
2981 		idlist = imsg.data;
2982 		if (idlist->nids > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS) {
2983 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2984 			break;
2985 		}
2986 		*nids = idlist->nids;
2987 		*ids = calloc(*nids, sizeof(**ids));
2988 		if (*ids == NULL) {
2989 			err = got_error_from_errno("calloc");
2990 			break;
2991 		}
2992 		memcpy(*ids, (uint8_t *)imsg.data + sizeof(idlist),
2993 		    *nids * sizeof(**ids));
2994 		break;
2995 	case GOT_IMSG_OBJ_ID_LIST_DONE:
2996 		*done = 1;
2997 		break;
2998 	default:
2999 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3000 		break;
3001 	}
3002 
3003 	imsg_free(&imsg);
3004 
3005 	return err;
3006 }
3007 
3008 const struct got_error *
3009 got_privsep_send_delta_reuse_req(struct imsgbuf *ibuf)
3010 {
3011 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_REQUEST, 0, 0, -1, NULL, 0)
3012 	    == -1)
3013 		return got_error_from_errno("imsg_compose DELTA_REUSE_REQUEST");
3014 
3015 	return flush_imsg(ibuf);
3016 }
3017 
3018 const struct got_error *
3019 got_privsep_send_reused_deltas(struct imsgbuf *ibuf,
3020     struct got_imsg_reused_delta *deltas, size_t ndeltas)
3021 {
3022 	const struct got_error *err = NULL;
3023 	struct ibuf *wbuf;
3024 	struct got_imsg_reused_deltas ideltas;
3025 	size_t i;
3026 
3027 	if (ndeltas > GOT_IMSG_REUSED_DELTAS_MAX_NDELTAS)
3028 		return got_error(GOT_ERR_NO_SPACE);
3029 
3030 	wbuf = imsg_create(ibuf, GOT_IMSG_REUSED_DELTAS, 0, 0,
3031 	    sizeof(ideltas) + ndeltas * sizeof(*deltas));
3032 	if (wbuf == NULL) {
3033 		err = got_error_from_errno("imsg_create REUSED_DELTAS");
3034 		return err;
3035 	}
3036 
3037 	ideltas.ndeltas = ndeltas;
3038 	if (imsg_add(wbuf, &ideltas, sizeof(ideltas)) == -1) {
3039 		err = got_error_from_errno("imsg_add REUSED_DELTAS");
3040 		ibuf_free(wbuf);
3041 		return err;
3042 	}
3043 
3044 	for (i = 0; i < ndeltas; i++) {
3045 		struct got_imsg_reused_delta *delta = &deltas[i];
3046 		if (imsg_add(wbuf, delta, sizeof(*delta)) == -1) {
3047 			err = got_error_from_errno("imsg_add REUSED_DELTAS");
3048 			ibuf_free(wbuf);
3049 			return err;
3050 		}
3051 	}
3052 	
3053 	wbuf->fd = -1;
3054 	imsg_close(ibuf, wbuf);
3055 
3056 	return flush_imsg(ibuf);
3057 }
3058 
3059 const struct got_error *
3060 got_privsep_send_reused_deltas_done(struct imsgbuf *ibuf)
3061 {
3062 	if (imsg_compose(ibuf, GOT_IMSG_DELTA_REUSE_DONE, 0, 0, -1, NULL, 0)
3063 	    == -1)
3064 		return got_error_from_errno("imsg_compose DELTA_REUSE_DONE");
3065 
3066 	return flush_imsg(ibuf);
3067 }
3068 
3069 const struct got_error *
3070 got_privsep_recv_reused_deltas(int *done, struct got_imsg_reused_delta *deltas,
3071     size_t *ndeltas, struct imsgbuf *ibuf)
3072 {
3073 	const struct got_error *err = NULL;
3074 	struct imsg imsg;
3075 	struct got_imsg_reused_deltas *ideltas;
3076 	size_t datalen;
3077 
3078 	*done = 0;
3079 	*ndeltas = 0;
3080 
3081 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
3082 	if (err)
3083 		return err;
3084 
3085 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
3086 	switch (imsg.hdr.type) {
3087 	case GOT_IMSG_REUSED_DELTAS:
3088 		if (datalen < sizeof(*ideltas)) {
3089 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3090 			break;
3091 		}
3092 		ideltas = imsg.data;
3093 		if (ideltas->ndeltas > GOT_IMSG_OBJ_ID_LIST_MAX_NIDS) {
3094 			err = got_error(GOT_ERR_PRIVSEP_LEN);
3095 			break;
3096 		}
3097 		*ndeltas = ideltas->ndeltas;
3098 		memcpy(deltas, (uint8_t *)imsg.data + sizeof(ideltas),
3099 		    *ndeltas * sizeof(*deltas));
3100 		break;
3101 	case GOT_IMSG_DELTA_REUSE_DONE:
3102 		*done = 1;
3103 		break;
3104 	default:
3105 		err = got_error(GOT_ERR_PRIVSEP_MSG);
3106 		break;
3107 	}
3108 
3109 	imsg_free(&imsg);
3110 
3111 	return err;
3112 }
3113 
3114 const struct got_error *
3115 got_privsep_unveil_exec_helpers(void)
3116 {
3117 	const char *helpers[] = {
3118 	    GOT_PATH_PROG_READ_PACK,
3119 	    GOT_PATH_PROG_READ_OBJECT,
3120 	    GOT_PATH_PROG_READ_COMMIT,
3121 	    GOT_PATH_PROG_READ_TREE,
3122 	    GOT_PATH_PROG_READ_BLOB,
3123 	    GOT_PATH_PROG_READ_TAG,
3124 	    GOT_PATH_PROG_READ_GITCONFIG,
3125 	    GOT_PATH_PROG_READ_GOTCONFIG,
3126 	    GOT_PATH_PROG_READ_PATCH,
3127 	    GOT_PATH_PROG_FETCH_PACK,
3128 	    GOT_PATH_PROG_INDEX_PACK,
3129 	    GOT_PATH_PROG_SEND_PACK,
3130 	};
3131 	size_t i;
3132 
3133 	for (i = 0; i < nitems(helpers); i++) {
3134 		if (unveil(helpers[i], "x") == 0)
3135 			continue;
3136 		return got_error_from_errno2("unveil", helpers[i]);
3137 	}
3138 
3139 	return NULL;
3140 }
3141 
3142 void
3143 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
3144 {
3145 	if (close(imsg_fds[0]) == -1) {
3146 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3147 		_exit(1);
3148 	}
3149 
3150 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
3151 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
3152 		_exit(1);
3153 	}
3154 
3155 	closefrom(GOT_IMSG_FD_CHILD + 1);
3156 
3157 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
3158 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
3159 		    strerror(errno));
3160 		_exit(1);
3161 	}
3162 }