Got Mirror

Blob

Date:: Fri Mar 20 20:23:18 2020 UTC
Message:: add support for fetching specific branches to 'got clone' and 'got fetch'
Actions:: History | Blame | Raw File
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/syslimits.h>
22 #include <sys/wait.h>
23 
24 #include <ctype.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 <imsg.h>
32 #include <sha1.h>
33 #include <zlib.h>
34 #include <time.h>
35 
36 #include "got_object.h"
37 #include "got_error.h"
38 #include "got_path.h"
39 #include "got_repository.h"
40 
41 #include "got_lib_sha1.h"
42 #include "got_lib_delta.h"
43 #include "got_lib_inflate.h"
44 #include "got_lib_object.h"
45 #include "got_lib_object_parse.h"
46 #include "got_lib_privsep.h"
47 #include "got_lib_pack.h"
48 
49 #ifndef MIN
50 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
51 #endif
52 
53 #ifndef nitems
54 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
55 #endif
56 
57 static const struct got_error *
58 poll_fd(int fd, int events, int timeout)
59 {
60 	struct pollfd pfd[1];
61 	int n;
62 
63 	pfd[0].fd = fd;
64 	pfd[0].events = events;
65 
66 	n = poll(pfd, 1, timeout);
67 	if (n == -1)
68 		return got_error_from_errno("poll");
69 	if (n == 0)
70 		return got_error(GOT_ERR_TIMEOUT);
71 	if (pfd[0].revents & (POLLERR | POLLNVAL))
72 		return got_error_from_errno("poll error");
73 	if (pfd[0].revents & (events | POLLHUP))
74 		return NULL;
75 
76 	return got_error(GOT_ERR_INTERRUPT);
77 }
78 
79 static const struct got_error *
80 read_imsg(struct imsgbuf *ibuf)
81 {
82 	const struct got_error *err;
83 	size_t n;
84 
85 	err = poll_fd(ibuf->fd, POLLIN, INFTIM);
86 	if (err)
87 		return err;
88 
89 	n = imsg_read(ibuf);
90 	if (n == -1) {
91 		if (errno == EAGAIN) /* Could be a file-descriptor leak. */
92 			return got_error(GOT_ERR_PRIVSEP_NO_FD);
93 		return got_error(GOT_ERR_PRIVSEP_READ);
94 	}
95 	if (n == 0)
96 		return got_error(GOT_ERR_PRIVSEP_PIPE);
97 
98 	return NULL;
99 }
100 
101 const struct got_error *
102 got_privsep_wait_for_child(pid_t pid)
103 {
104 	int child_status;
105 
106 	if (waitpid(pid, &child_status, 0) == -1)
107 		return got_error_from_errno("waitpid");
108 
109 	if (!WIFEXITED(child_status))
110 		return got_error(GOT_ERR_PRIVSEP_DIED);
111 
112 	if (WEXITSTATUS(child_status) != 0)
113 		return got_error(GOT_ERR_PRIVSEP_EXIT);
114 
115 	return NULL;
116 }
117 
118 static const struct got_error *
119 recv_imsg_error(struct imsg *imsg, size_t datalen)
120 {
121 	struct got_imsg_error *ierr;
122 
123 	if (datalen != sizeof(*ierr))
124 		return got_error(GOT_ERR_PRIVSEP_LEN);
125 
126 	ierr = imsg->data;
127 	if (ierr->code == GOT_ERR_ERRNO) {
128 		static struct got_error serr;
129 		serr.code = GOT_ERR_ERRNO;
130 		serr.msg = strerror(ierr->errno_code);
131 		return &serr;
132 	}
133 
134 	return got_error(ierr->code);
135 }
136 
137 const struct got_error *
138 got_privsep_recv_imsg(struct imsg *imsg, struct imsgbuf *ibuf,
139     size_t min_datalen)
140 {
141 	const struct got_error *err;
142 	ssize_t n;
143 
144 	n = imsg_get(ibuf, imsg);
145 	if (n == -1)
146 		return got_error_from_errno("imsg_get");
147 
148 	while (n == 0) {
149 		err = read_imsg(ibuf);
150 		if (err)
151 			return err;
152 		n = imsg_get(ibuf, imsg);
153 		if (n == -1)
154 			return got_error_from_errno("imsg_get");
155 	}
156 
157 	if (imsg->hdr.len < IMSG_HEADER_SIZE + min_datalen)
158 		return got_error(GOT_ERR_PRIVSEP_LEN);
159 
160 	if (imsg->hdr.type == GOT_IMSG_ERROR) {
161 		size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
162 		return recv_imsg_error(imsg, datalen);
163 	}
164 
165 	return NULL;
166 }
167 
168 /* Attempt to send an error in an imsg. Complain on stderr as a last resort. */
169 void
170 got_privsep_send_error(struct imsgbuf *ibuf, const struct got_error *err)
171 {
172 	const struct got_error *poll_err;
173 	struct got_imsg_error ierr;
174 	int ret;
175 
176 	ierr.code = err->code;
177 	if (err->code == GOT_ERR_ERRNO)
178 		ierr.errno_code = errno;
179 	else
180 		ierr.errno_code = 0;
181 	ret = imsg_compose(ibuf, GOT_IMSG_ERROR, 0, 0, -1, &ierr, sizeof(ierr));
182 	if (ret == -1) {
183 		fprintf(stderr, "%s: error %d \"%s\": imsg_compose: %s\n",
184 		    getprogname(), err->code, err->msg, strerror(errno));
185 		return;
186 	}
187 
188 	poll_err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
189 	if (poll_err) {
190 		fprintf(stderr, "%s: error %d \"%s\": poll: %s\n",
191 		    getprogname(), err->code, err->msg, poll_err->msg);
192 		return;
193 	}
194 
195 	ret = imsg_flush(ibuf);
196 	if (ret == -1) {
197 		fprintf(stderr, "%s: error %d \"%s\": imsg_flush: %s\n",
198 		    getprogname(), err->code, err->msg, strerror(errno));
199 		return;
200 	}
201 }
202 
203 static const struct got_error *
204 flush_imsg(struct imsgbuf *ibuf)
205 {
206 	const struct got_error *err;
207 
208 	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
209 	if (err)
210 		return err;
211 
212 	if (imsg_flush(ibuf) == -1)
213 		return got_error_from_errno("imsg_flush");
214 
215 	return NULL;
216 }
217 
218 const struct got_error *
219 got_privsep_send_stop(int fd)
220 {
221 	const struct got_error *err = NULL;
222 	struct imsgbuf ibuf;
223 
224 	imsg_init(&ibuf, fd);
225 
226 	if (imsg_compose(&ibuf, GOT_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
227 		return got_error_from_errno("imsg_compose STOP");
228 
229 	err = flush_imsg(&ibuf);
230 	imsg_clear(&ibuf);
231 	return err;
232 }
233 
234 const struct got_error *
235 got_privsep_send_obj_req(struct imsgbuf *ibuf, int fd)
236 {
237 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_REQUEST, 0, 0, fd, NULL, 0)
238 	    == -1)
239 		return got_error_from_errno("imsg_compose OBJECT_REQUEST");
240 
241 	return flush_imsg(ibuf);
242 }
243 
244 const struct got_error *
245 got_privsep_send_commit_req(struct imsgbuf *ibuf, int fd,
246     struct got_object_id *id, int pack_idx)
247 {
248 	const struct got_error *err = NULL;
249 	struct got_imsg_packed_object iobj, *iobjp;
250 	size_t len;
251 
252 	if (id) { /* commit is packed */
253 		iobj.idx = pack_idx;
254 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
255 		iobjp = &iobj;
256 		len = sizeof(iobj);
257 	} else {
258 		iobjp = NULL;
259 		len = 0;
260 	}
261 
262 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_REQUEST, 0, 0, fd, iobjp, len)
263 	    == -1) {
264 		err = got_error_from_errno("imsg_compose COMMIT_REQUEST");
265 		close(fd);
266 		return err;
267 	}
268 
269 	return flush_imsg(ibuf);
270 }
271 
272 const struct got_error *
273 got_privsep_send_tree_req(struct imsgbuf *ibuf, int fd,
274     struct got_object_id *id, int pack_idx)
275 {
276 	const struct got_error *err = NULL;
277 	struct ibuf *wbuf;
278 	size_t len = id ? sizeof(struct got_imsg_packed_object) : 0;
279 
280 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_REQUEST, 0, 0, len);
281 	if (wbuf == NULL)
282 		return got_error_from_errno("imsg_create TREE_REQUEST");
283 
284 	if (id) { /* tree is packed */
285 		if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
286 			err = got_error_from_errno("imsg_add TREE_ENTRY");
287 			ibuf_free(wbuf);
288 			return err;
289 		}
290 
291 		if (imsg_add(wbuf, &pack_idx, sizeof(pack_idx)) == -1) {
292 			err = got_error_from_errno("imsg_add TREE_ENTRY");
293 			ibuf_free(wbuf);
294 			return err;
295 		}
296 	}
297 
298 	wbuf->fd = fd;
299 	imsg_close(ibuf, wbuf);
300 
301 	return flush_imsg(ibuf);
302 }
303 
304 const struct got_error *
305 got_privsep_send_tag_req(struct imsgbuf *ibuf, int fd,
306     struct got_object_id *id, int pack_idx)
307 {
308 	struct got_imsg_packed_object iobj, *iobjp;
309 	size_t len;
310 
311 	if (id) { /* tag is packed */
312 		iobj.idx = pack_idx;
313 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
314 		iobjp = &iobj;
315 		len = sizeof(iobj);
316 	} else {
317 		iobjp = NULL;
318 		len = 0;
319 	}
320 
321 	if (imsg_compose(ibuf, GOT_IMSG_TAG_REQUEST, 0, 0, fd, iobjp, len)
322 	    == -1)
323 		return got_error_from_errno("imsg_compose TAG_REQUEST");
324 
325 	return flush_imsg(ibuf);
326 }
327 
328 const struct got_error *
329 got_privsep_send_blob_req(struct imsgbuf *ibuf, int infd,
330     struct got_object_id *id, int pack_idx)
331 {
332 	const struct got_error *err = NULL;
333 	struct got_imsg_packed_object iobj, *iobjp;
334 	size_t len;
335 
336 	if (id) { /* blob is packed */
337 		iobj.idx = pack_idx;
338 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
339 		iobjp = &iobj;
340 		len = sizeof(iobj);
341 	} else {
342 		iobjp = NULL;
343 		len = 0;
344 	}
345 
346 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_REQUEST, 0, 0, infd, iobjp, len)
347 	    == -1) {
348 		err = got_error_from_errno("imsg_compose BLOB_REQUEST");
349 		close(infd);
350 		return err;
351 	}
352 
353 	return flush_imsg(ibuf);
354 }
355 
356 const struct got_error *
357 got_privsep_send_blob_outfd(struct imsgbuf *ibuf, int outfd)
358 {
359 	const struct got_error *err = NULL;
360 
361 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_OUTFD, 0, 0, outfd, NULL, 0)
362 	    == -1) {
363 		err = got_error_from_errno("imsg_compose BLOB_OUTFD");
364 		close(outfd);
365 		return err;
366 	}
367 
368 	return flush_imsg(ibuf);
369 }
370 
371 static const struct got_error *
372 send_fd(struct imsgbuf *ibuf, int imsg_code, int fd)
373 {
374 	const struct got_error *err = NULL;
375 
376 	if (imsg_compose(ibuf, imsg_code, 0, 0, fd, NULL, 0) == -1) {
377 		err = got_error_from_errno("imsg_compose TMPFD");
378 		close(fd);
379 		return err;
380 	}
381 
382 	return flush_imsg(ibuf);
383 }
384 
385 const struct got_error *
386 got_privsep_send_tmpfd(struct imsgbuf *ibuf, int fd)
387 {
388 	return send_fd(ibuf, GOT_IMSG_TMPFD, fd);
389 }
390 
391 const struct got_error *
392 got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj)
393 {
394 	struct got_imsg_object iobj;
395 
396 	memcpy(iobj.id, obj->id.sha1, sizeof(iobj.id));
397 	iobj.type = obj->type;
398 	iobj.flags = obj->flags;
399 	iobj.hdrlen = obj->hdrlen;
400 	iobj.size = obj->size;
401 	if (iobj.flags & GOT_OBJ_FLAG_PACKED) {
402 		iobj.pack_offset = obj->pack_offset;
403 		iobj.pack_idx = obj->pack_idx;
404 	}
405 
406 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
407 	    == -1)
408 		return got_error_from_errno("imsg_compose OBJECT");
409 
410 	return flush_imsg(ibuf);
411 }
412 
413 const struct got_error *
414 got_privsep_send_fetch_req(struct imsgbuf *ibuf, int fd,
415    struct got_pathlist_head *have_refs, int fetch_all_branches,
416    struct got_pathlist_head *wanted_branches)
417 {
418 	const struct got_error *err = NULL;
419 	struct ibuf *wbuf;
420 	size_t len;
421 	struct got_pathlist_entry *pe;
422 	struct got_imsg_fetch_request fetchreq;
423 
424 	memset(&fetchreq, 0, sizeof(fetchreq));
425 	fetchreq.fetch_all_branches = fetch_all_branches;
426 	TAILQ_FOREACH(pe, have_refs, entry)
427 		fetchreq.n_have_refs++;
428 	TAILQ_FOREACH(pe, wanted_branches, entry)
429 		fetchreq.n_wanted_branches++;
430 	len = sizeof(struct got_imsg_fetch_request);
431 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
432 		close(fd);
433 		return got_error(GOT_ERR_NO_SPACE);
434 	}
435 
436 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_REQUEST, 0, 0, fd,
437 	    &fetchreq, sizeof(fetchreq)) == -1)
438 		return got_error_from_errno(
439 		    "imsg_compose FETCH_SERVER_PROGRESS");
440 
441 	err = flush_imsg(ibuf);
442 	if (err) {
443 		close(fd);
444 		return err;
445 	}
446 	fd = -1;
447 
448 	TAILQ_FOREACH(pe, have_refs, entry) {
449 		const char *name = pe->path;
450 		size_t name_len = pe->path_len;
451 		struct got_object_id *id = pe->data;
452 
453 		len = sizeof(struct got_imsg_fetch_have_ref) + name_len;
454 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_HAVE_REF, 0, 0, len);
455 		if (wbuf == NULL)
456 			return got_error_from_errno("imsg_create FETCH_HAVE_REF");
457 
458 		/* Keep in sync with struct got_imsg_fetch_have_ref! */
459 		if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1) {
460 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
461 			ibuf_free(wbuf);
462 			return err;
463 		}
464 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
465 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
466 			ibuf_free(wbuf);
467 			return err;
468 		}
469 		if (imsg_add(wbuf, name, name_len) == -1) {
470 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
471 			ibuf_free(wbuf);
472 			return err;
473 		}
474 
475 		wbuf->fd = -1;
476 		imsg_close(ibuf, wbuf);
477 		err = flush_imsg(ibuf);
478 		if (err)
479 			return err;
480 	}
481 
482 	TAILQ_FOREACH(pe, wanted_branches, entry) {
483 		const char *name = pe->path;
484 		size_t name_len = pe->path_len;
485 
486 		len = sizeof(struct got_imsg_fetch_wanted_branch) + name_len;
487 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_BRANCH, 0, 0,
488 		    len);
489 		if (wbuf == NULL)
490 			return got_error_from_errno(
491 			     "imsg_create FETCH_WANTED_BRANCH");
492 
493 		/* Keep in sync with struct got_imsg_fetch_wanted_branch! */
494 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
495 			err = got_error_from_errno(
496 			    "imsg_add FETCH_WANTED_BRANCH");
497 			ibuf_free(wbuf);
498 			return err;
499 		}
500 		if (imsg_add(wbuf, name, name_len) == -1) {
501 			err = got_error_from_errno(
502 			     "imsg_add FETCH_WANTED_BRANCH");
503 			ibuf_free(wbuf);
504 			return err;
505 		}
506 
507 		wbuf->fd = -1;
508 		imsg_close(ibuf, wbuf);
509 		err = flush_imsg(ibuf);
510 		if (err)
511 			return err;
512 	}
513 
514 	return NULL;
515 
516 }
517 
518 const struct got_error *
519 got_privsep_send_fetch_outfd(struct imsgbuf *ibuf, int fd)
520 {
521 	return send_fd(ibuf, GOT_IMSG_FETCH_OUTFD, fd);
522 }
523 
524 
525 const struct got_error *
526 got_privsep_send_fetch_symrefs(struct imsgbuf *ibuf,
527     struct got_pathlist_head *symrefs)
528 {
529 	const struct got_error *err = NULL;
530 	struct ibuf *wbuf;
531 	size_t len, nsymrefs = 0;
532 	struct got_pathlist_entry *pe;
533 
534 	len = sizeof(struct got_imsg_fetch_symrefs);
535 	TAILQ_FOREACH(pe, symrefs, entry) {
536 		const char *target = pe->data;
537 		len += sizeof(struct got_imsg_fetch_symref) +
538 		    pe->path_len + strlen(target);
539 		nsymrefs++;
540 	}
541 
542 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
543 		return got_error(GOT_ERR_NO_SPACE);
544 
545 	wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_SYMREFS, 0, 0, len);
546 	if (wbuf == NULL)
547 		return got_error_from_errno("imsg_create FETCH_SYMREFS");
548 
549 	/* Keep in sync with struct got_imsg_fetch_symrefs definition! */
550 	if (imsg_add(wbuf, &nsymrefs, sizeof(nsymrefs)) == -1) {
551 		err = got_error_from_errno("imsg_add FETCH_SYMREFS");
552 		ibuf_free(wbuf);
553 		return err;
554 	}
555 
556 	TAILQ_FOREACH(pe, symrefs, entry) {
557 		const char *name = pe->path;
558 		size_t name_len = pe->path_len;
559 		const char *target = pe->data;
560 		size_t target_len = strlen(target);
561 
562 		/* Keep in sync with struct got_imsg_fetch_symref definition! */
563 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
564 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
565 			ibuf_free(wbuf);
566 			return err;
567 		}
568 		if (imsg_add(wbuf, &target_len, sizeof(target_len)) == -1) {
569 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
570 			ibuf_free(wbuf);
571 			return err;
572 		}
573 		if (imsg_add(wbuf, name, name_len) == -1) {
574 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
575 			ibuf_free(wbuf);
576 			return err;
577 		}
578 		if (imsg_add(wbuf, target, target_len) == -1) {
579 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
580 			ibuf_free(wbuf);
581 			return err;
582 		}
583 	}
584 
585 	wbuf->fd = -1;
586 	imsg_close(ibuf, wbuf);
587 	return flush_imsg(ibuf);
588 }
589 
590 const struct got_error *
591 got_privsep_send_fetch_ref(struct imsgbuf *ibuf,
592     struct got_object_id *refid, const char *refname)
593 {
594 	const struct got_error *err = NULL;
595 	struct ibuf *wbuf;
596 	size_t len, reflen = strlen(refname);
597 
598 	len = sizeof(struct got_imsg_fetch_ref) + reflen;
599 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
600 		return got_error(GOT_ERR_NO_SPACE);
601 
602 	wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_REF, 0, 0, len);
603 	if (wbuf == NULL)
604 		return got_error_from_errno("imsg_create FETCH_REF");
605 
606 	/* Keep in sync with struct got_imsg_fetch_ref definition! */
607 	if (imsg_add(wbuf, refid->sha1, SHA1_DIGEST_LENGTH) == -1) {
608 		err = got_error_from_errno("imsg_add FETCH_REF");
609 		ibuf_free(wbuf);
610 		return err;
611 	}
612 	if (imsg_add(wbuf, refname, reflen) == -1) {
613 		err = got_error_from_errno("imsg_add FETCH_REF");
614 		ibuf_free(wbuf);
615 		return err;
616 	}
617 
618 	wbuf->fd = -1;
619 	imsg_close(ibuf, wbuf);
620 	return flush_imsg(ibuf);
621 }
622 
623 const struct got_error *
624 got_privsep_send_fetch_server_progress(struct imsgbuf *ibuf, const char *msg,
625     size_t msglen)
626 {
627 	if (msglen > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
628 		return got_error(GOT_ERR_NO_SPACE);
629 
630 	if (msglen == 0)
631 		return NULL;
632 
633 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_SERVER_PROGRESS, 0, 0, -1,
634 	    msg, msglen) == -1)
635 		return got_error_from_errno(
636 		    "imsg_compose FETCH_SERVER_PROGRESS");
637 
638 	return flush_imsg(ibuf);
639 }
640 
641 const struct got_error *
642 got_privsep_send_fetch_download_progress(struct imsgbuf *ibuf, off_t bytes)
643 {
644 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_DOWNLOAD_PROGRESS, 0, 0, -1,
645 	    &bytes, sizeof(bytes)) == -1)
646 		return got_error_from_errno(
647 		    "imsg_compose FETCH_DOWNLOAD_PROGRESS");
648 
649 	return flush_imsg(ibuf);
650 }
651 
652 const struct got_error *
653 got_privsep_send_fetch_done(struct imsgbuf *ibuf, struct got_object_id hash)
654 {
655 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_DONE, 0, 0, -1,
656 	    hash.sha1, SHA1_DIGEST_LENGTH) == -1)
657 		return got_error_from_errno("imsg_compose FETCH");
658 	return flush_imsg(ibuf);
659 }
660 
661 
662 const struct got_error *
663 got_privsep_recv_fetch_progress(int *done, struct got_object_id **id,
664     char **refname, struct got_pathlist_head *symrefs, char **server_progress,
665     off_t *packfile_size, struct imsgbuf *ibuf)
666 {
667 	const struct got_error *err = NULL;
668 	struct imsg imsg;
669 	size_t datalen;
670 	struct got_imsg_fetch_symrefs *isymrefs = NULL;
671 	size_t n, remain;
672 	off_t off;
673 	int i;
674 
675 	*done = 0;
676 	*id = NULL;
677 	*refname = NULL;
678 	*server_progress = NULL;
679 	*packfile_size = 0;
680 
681 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
682 	if (err)
683 		return err;
684 
685 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
686 	switch (imsg.hdr.type) {
687 	case GOT_IMSG_ERROR:
688 		if (datalen < sizeof(struct got_imsg_error)) {
689 			err = got_error(GOT_ERR_PRIVSEP_LEN);
690 			break;
691 		}
692 		err = recv_imsg_error(&imsg, datalen);
693 		break;
694 	case GOT_IMSG_FETCH_SYMREFS:
695 		if (datalen < sizeof(*isymrefs)) {
696 			err = got_error(GOT_ERR_PRIVSEP_LEN);
697 			break;
698 		}
699 		if (isymrefs != NULL) {
700 			err = got_error(GOT_ERR_PRIVSEP_MSG);
701 			break;
702 		}
703 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
704 		off = sizeof(*isymrefs);
705 		remain = datalen - off;
706 		for (n = 0; n < isymrefs->nsymrefs; n++) {
707 			struct got_imsg_fetch_symref *s;
708 			char *name, *target;
709 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
710 				err = got_error(GOT_ERR_PRIVSEP_LEN);
711 				goto done;
712 			}
713 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
714 			off += sizeof(*s);
715 			remain -= sizeof(*s);
716 			if (remain < s->name_len) {
717 				err = got_error(GOT_ERR_PRIVSEP_LEN);
718 				goto done;
719 			}
720 			name = strndup(imsg.data + off, s->name_len);
721 			if (name == NULL) {
722 				err = got_error_from_errno("strndup");
723 				goto done;
724 			}
725 			off += s->name_len;
726 			remain -= s->name_len;
727 			if (remain < s->target_len) {
728 				err = got_error(GOT_ERR_PRIVSEP_LEN);
729 				free(name);
730 				goto done;
731 			}
732 			target = strndup(imsg.data + off, s->target_len);
733 			if (target == NULL) {
734 				err = got_error_from_errno("strndup");
735 				free(name);
736 				goto done;
737 			}
738 			off += s->target_len;
739 			remain -= s->target_len;
740 			err = got_pathlist_append(symrefs, name, target);
741 			if (err) {
742 				free(name);
743 				free(target);
744 				goto done;
745 			}
746 		}
747 		break;
748 	case GOT_IMSG_FETCH_REF:
749 		if (datalen <= SHA1_DIGEST_LENGTH) {
750 			err = got_error(GOT_ERR_PRIVSEP_MSG);
751 			break;
752 		}
753 		*id = malloc(sizeof(**id));
754 		if (*id == NULL) {
755 			err = got_error_from_errno("malloc");
756 			break;
757 		}
758 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
759 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
760 		    datalen - SHA1_DIGEST_LENGTH);
761 		if (*refname == NULL) {
762 			err = got_error_from_errno("strndup");
763 			break;
764 		}
765 		break;
766 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
767 		if (datalen == 0) {
768 			err = got_error(GOT_ERR_PRIVSEP_LEN);
769 			break;
770 		}
771 		*server_progress = strndup(imsg.data, datalen);
772 		if (*server_progress == NULL) {
773 			err = got_error_from_errno("strndup");
774 			break;
775 		}
776 		for (i = 0; i < datalen; i++) {
777 			if (!isprint((unsigned char)(*server_progress)[i]) &&
778 			    !isspace((unsigned char)(*server_progress)[i])) {
779 				err = got_error(GOT_ERR_PRIVSEP_MSG);
780 				free(*server_progress);
781 				*server_progress = NULL;
782 				goto done;
783 			}
784 		}
785 		break;
786 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
787 		if (datalen < sizeof(*packfile_size)) {
788 			err = got_error(GOT_ERR_PRIVSEP_MSG);
789 			break;
790 		}
791 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
792 		break;
793 	case GOT_IMSG_FETCH_DONE:
794 		*id = malloc(sizeof(**id));
795 		if (*id == NULL) {
796 			err = got_error_from_errno("malloc");
797 			break;
798 		}
799 		if (datalen != SHA1_DIGEST_LENGTH) {
800 			err = got_error(GOT_ERR_PRIVSEP_MSG);
801 			break;
802 		}
803 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
804 		*done = 1;
805 		break;
806 	default:
807 		err = got_error(GOT_ERR_PRIVSEP_MSG);
808 		break;
809 	}
810 done:
811 	if (err) {
812 		free(*id);
813 		*id = NULL;
814 		free(*refname);
815 		*refname = NULL;
816 	}
817 	imsg_free(&imsg);
818 	return err;
819 }
820 
821 const struct got_error *
822 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_hash,
823     int fd)
824 {
825 	const struct got_error *err = NULL;
826 
827 	/* Keep in sync with struct got_imsg_index_pack_request */
828 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
829 	    pack_hash, SHA1_DIGEST_LENGTH) == -1) {
830 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
831 		close(fd);
832 		return err;
833 	}
834 	return flush_imsg(ibuf);
835 }
836 
837 const struct got_error *
838 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
839 {
840 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
841 }
842 
843 const struct got_error *
844 got_privsep_send_index_pack_progress(struct imsgbuf *ibuf, int nobj_total,
845     int nobj_indexed, int nobj_loose, int nobj_resolved)
846 {
847 	struct got_imsg_index_pack_progress iprogress;
848 
849 	iprogress.nobj_total = nobj_total;
850 	iprogress.nobj_indexed = nobj_indexed;
851 	iprogress.nobj_loose = nobj_loose;
852 	iprogress.nobj_resolved = nobj_resolved;
853 
854 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_PROGRESS, 0, 0, -1,
855 	    &iprogress, sizeof(iprogress)) == -1)
856 		return got_error_from_errno("imsg_compose IDXPACK_PROGRESS");
857 
858 	return flush_imsg(ibuf);
859 }
860 
861 const struct got_error *
862 got_privsep_send_index_pack_done(struct imsgbuf *ibuf)
863 {
864 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_DONE, 0, 0, -1, NULL, 0) == -1)
865 		return got_error_from_errno("imsg_compose FETCH");
866 	return flush_imsg(ibuf);
867 }
868 
869 const struct got_error *
870 got_privsep_recv_index_progress(int *done, int *nobj_total,
871     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
872     struct imsgbuf *ibuf)
873 {
874 	const struct got_error *err = NULL;
875 	struct imsg imsg;
876 	struct got_imsg_index_pack_progress *iprogress;
877 	size_t datalen;
878 
879 	*done = 0;
880 	*nobj_total = 0;
881 	*nobj_indexed = 0;
882 	*nobj_resolved = 0;
883 
884 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
885 	if (err)
886 		return err;
887 
888 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
889 	switch (imsg.hdr.type) {
890 	case GOT_IMSG_ERROR:
891 		if (datalen < sizeof(struct got_imsg_error)) {
892 			err = got_error(GOT_ERR_PRIVSEP_LEN);
893 			break;
894 		}
895 		err = recv_imsg_error(&imsg, datalen);
896 		break;
897 	case GOT_IMSG_IDXPACK_PROGRESS:
898 		if (datalen < sizeof(*iprogress)) {
899 			err = got_error(GOT_ERR_PRIVSEP_LEN);
900 			break;
901 		}
902 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
903 		*nobj_total = iprogress->nobj_total;
904 		*nobj_indexed = iprogress->nobj_indexed;
905 		*nobj_loose = iprogress->nobj_loose;
906 		*nobj_resolved = iprogress->nobj_resolved;
907 		break;
908 	case GOT_IMSG_IDXPACK_DONE:
909 		if (datalen != 0) {
910 			err = got_error(GOT_ERR_PRIVSEP_LEN);
911 			break;
912 		}
913 		*done = 1;
914 		break;
915 	default:
916 		err = got_error(GOT_ERR_PRIVSEP_MSG);
917 		break;
918 	}
919 
920 	imsg_free(&imsg);
921 	return err;
922 }
923 
924 const struct got_error *
925 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
926     struct imsgbuf *ibuf)
927 {
928 	const struct got_error *err = NULL;
929 	struct got_imsg_object *iobj;
930 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
931 
932 	if (datalen != sizeof(*iobj))
933 		return got_error(GOT_ERR_PRIVSEP_LEN);
934 	iobj = imsg->data;
935 
936 	*obj = calloc(1, sizeof(**obj));
937 	if (*obj == NULL)
938 		return got_error_from_errno("calloc");
939 
940 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
941 	(*obj)->type = iobj->type;
942 	(*obj)->flags = iobj->flags;
943 	(*obj)->hdrlen = iobj->hdrlen;
944 	(*obj)->size = iobj->size;
945 	/* path_packfile is handled by caller */
946 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
947 		(*obj)->pack_offset = iobj->pack_offset;
948 		(*obj)->pack_idx = iobj->pack_idx;
949 	}
950 
951 	return err;
952 }
953 
954 const struct got_error *
955 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
956 {
957 	const struct got_error *err = NULL;
958 	struct imsg imsg;
959 	const size_t min_datalen =
960 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
961 
962 	*obj = NULL;
963 
964 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
965 	if (err)
966 		return err;
967 
968 	switch (imsg.hdr.type) {
969 	case GOT_IMSG_OBJECT:
970 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
971 		break;
972 	default:
973 		err = got_error(GOT_ERR_PRIVSEP_MSG);
974 		break;
975 	}
976 
977 	imsg_free(&imsg);
978 
979 	return err;
980 }
981 
982 static const struct got_error *
983 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
984     size_t logmsg_len)
985 {
986 	const struct got_error *err = NULL;
987 	size_t offset, remain;
988 
989 	offset = 0;
990 	remain = logmsg_len;
991 	while (remain > 0) {
992 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
993 
994 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
995 		    commit->logmsg + offset, n) == -1) {
996 			err = got_error_from_errno("imsg_compose "
997 			    "COMMIT_LOGMSG");
998 			break;
999 		}
1000 
1001 		err = flush_imsg(ibuf);
1002 		if (err)
1003 			break;
1004 
1005 		offset += n;
1006 		remain -= n;
1007 	}
1008 
1009 	return err;
1010 }
1011 
1012 const struct got_error *
1013 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
1014 {
1015 	const struct got_error *err = NULL;
1016 	struct got_imsg_commit_object *icommit;
1017 	uint8_t *buf;
1018 	size_t len, total;
1019 	struct got_object_qid *qid;
1020 	size_t author_len = strlen(commit->author);
1021 	size_t committer_len = strlen(commit->committer);
1022 	size_t logmsg_len = strlen(commit->logmsg);
1023 
1024 	total = sizeof(*icommit) + author_len + committer_len +
1025 	    commit->nparents * SHA1_DIGEST_LENGTH;
1026 
1027 	buf = malloc(total);
1028 	if (buf == NULL)
1029 		return got_error_from_errno("malloc");
1030 
1031 	icommit = (struct got_imsg_commit_object *)buf;
1032 	memcpy(icommit->tree_id, commit->tree_id->sha1,
1033 	    sizeof(icommit->tree_id));
1034 	icommit->author_len = author_len;
1035 	icommit->author_time = commit->author_time;
1036 	icommit->author_gmtoff = commit->author_gmtoff;
1037 	icommit->committer_len = committer_len;
1038 	icommit->committer_time = commit->committer_time;
1039 	icommit->committer_gmtoff = commit->committer_gmtoff;
1040 	icommit->logmsg_len = logmsg_len;
1041 	icommit->nparents = commit->nparents;
1042 
1043 	len = sizeof(*icommit);
1044 	memcpy(buf + len, commit->author, author_len);
1045 	len += author_len;
1046 	memcpy(buf + len, commit->committer, committer_len);
1047 	len += committer_len;
1048 	SIMPLEQ_FOREACH(qid, &commit->parent_ids, entry) {
1049 		memcpy(buf + len, qid->id, SHA1_DIGEST_LENGTH);
1050 		len += SHA1_DIGEST_LENGTH;
1051 	}
1052 
1053 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
1054 		err = got_error_from_errno("imsg_compose COMMIT");
1055 		goto done;
1056 	}
1057 
1058 	if (logmsg_len == 0 ||
1059 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1060 		err = flush_imsg(ibuf);
1061 		if (err)
1062 			goto done;
1063 	}
1064 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
1065 done:
1066 	free(buf);
1067 	return err;
1068 }
1069 
1070 static const struct got_error *
1071 get_commit_from_imsg(struct got_commit_object **commit,
1072     struct imsg *imsg, size_t datalen, struct imsgbuf *ibuf)
1073 {
1074 	const struct got_error *err = NULL;
1075 	struct got_imsg_commit_object *icommit;
1076 	size_t len = 0;
1077 	int i;
1078 
1079 	if (datalen < sizeof(*icommit))
1080 		return got_error(GOT_ERR_PRIVSEP_LEN);
1081 
1082 	icommit = imsg->data;
1083 	if (datalen != sizeof(*icommit) + icommit->author_len +
1084 	    icommit->committer_len +
1085 	    icommit->nparents * SHA1_DIGEST_LENGTH)
1086 		return got_error(GOT_ERR_PRIVSEP_LEN);
1087 
1088 	if (icommit->nparents < 0)
1089 		return got_error(GOT_ERR_PRIVSEP_LEN);
1090 
1091 	len += sizeof(*icommit);
1092 
1093 	*commit = got_object_commit_alloc_partial();
1094 	if (*commit == NULL)
1095 		return got_error_from_errno(
1096 		    "got_object_commit_alloc_partial");
1097 
1098 	memcpy((*commit)->tree_id->sha1, icommit->tree_id,
1099 	    SHA1_DIGEST_LENGTH);
1100 	(*commit)->author_time = icommit->author_time;
1101 	(*commit)->author_gmtoff = icommit->author_gmtoff;
1102 	(*commit)->committer_time = icommit->committer_time;
1103 	(*commit)->committer_gmtoff = icommit->committer_gmtoff;
1104 
1105 	if (icommit->author_len == 0) {
1106 		(*commit)->author = strdup("");
1107 		if ((*commit)->author == NULL) {
1108 			err = got_error_from_errno("strdup");
1109 			goto done;
1110 		}
1111 	} else {
1112 		(*commit)->author = malloc(icommit->author_len + 1);
1113 		if ((*commit)->author == NULL) {
1114 			err = got_error_from_errno("malloc");
1115 			goto done;
1116 		}
1117 		memcpy((*commit)->author, imsg->data + len,
1118 		    icommit->author_len);
1119 		(*commit)->author[icommit->author_len] = '\0';
1120 	}
1121 	len += icommit->author_len;
1122 
1123 	if (icommit->committer_len == 0) {
1124 		(*commit)->committer = strdup("");
1125 		if ((*commit)->committer == NULL) {
1126 			err = got_error_from_errno("strdup");
1127 			goto done;
1128 		}
1129 	} else {
1130 		(*commit)->committer =
1131 		    malloc(icommit->committer_len + 1);
1132 		if ((*commit)->committer == NULL) {
1133 			err = got_error_from_errno("malloc");
1134 			goto done;
1135 		}
1136 		memcpy((*commit)->committer, imsg->data + len,
1137 		    icommit->committer_len);
1138 		(*commit)->committer[icommit->committer_len] = '\0';
1139 	}
1140 	len += icommit->committer_len;
1141 
1142 	if (icommit->logmsg_len == 0) {
1143 		(*commit)->logmsg = strdup("");
1144 		if ((*commit)->logmsg == NULL) {
1145 			err = got_error_from_errno("strdup");
1146 			goto done;
1147 		}
1148 	} else {
1149 		size_t offset = 0, remain = icommit->logmsg_len;
1150 
1151 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1152 		if ((*commit)->logmsg == NULL) {
1153 			err = got_error_from_errno("malloc");
1154 			goto done;
1155 		}
1156 		while (remain > 0) {
1157 			struct imsg imsg_log;
1158 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1159 			    remain);
1160 
1161 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1162 			if (err)
1163 				goto done;
1164 
1165 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1166 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1167 				goto done;
1168 			}
1169 
1170 			memcpy((*commit)->logmsg + offset,
1171 			    imsg_log.data, n);
1172 			imsg_free(&imsg_log);
1173 			offset += n;
1174 			remain -= n;
1175 		}
1176 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1177 	}
1178 
1179 	for (i = 0; i < icommit->nparents; i++) {
1180 		struct got_object_qid *qid;
1181 
1182 		err = got_object_qid_alloc_partial(&qid);
1183 		if (err)
1184 			break;
1185 		memcpy(qid->id, imsg->data + len +
1186 		    i * SHA1_DIGEST_LENGTH, sizeof(*qid->id));
1187 		SIMPLEQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1188 		(*commit)->nparents++;
1189 	}
1190 done:
1191 	if (err) {
1192 		got_object_commit_close(*commit);
1193 		*commit = NULL;
1194 	}
1195 	return err;
1196 }
1197 
1198 const struct got_error *
1199 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1200 {
1201 	const struct got_error *err = NULL;
1202 	struct imsg imsg;
1203 	size_t datalen;
1204 	const size_t min_datalen =
1205 	    MIN(sizeof(struct got_imsg_error),
1206 	    sizeof(struct got_imsg_commit_object));
1207 
1208 	*commit = NULL;
1209 
1210 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1211 	if (err)
1212 		return err;
1213 
1214 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1215 
1216 	switch (imsg.hdr.type) {
1217 	case GOT_IMSG_COMMIT:
1218 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1219 		break;
1220 	default:
1221 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1222 		break;
1223 	}
1224 
1225 	imsg_free(&imsg);
1226 
1227 	return err;
1228 }
1229 
1230 const struct got_error *
1231 got_privsep_send_tree(struct imsgbuf *ibuf, struct got_pathlist_head *entries,
1232     int nentries)
1233 {
1234 	const struct got_error *err = NULL;
1235 	struct got_imsg_tree_object itree;
1236 	struct got_pathlist_entry *pe;
1237 	size_t totlen;
1238 	int nimsg; /* number of imsg queued in ibuf */
1239 
1240 	itree.nentries = nentries;
1241 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1242 	    == -1)
1243 		return got_error_from_errno("imsg_compose TREE");
1244 
1245 	totlen = sizeof(itree);
1246 	nimsg = 1;
1247 	TAILQ_FOREACH(pe, entries, entry) {
1248 		const char *name = pe->path;
1249 		struct got_parsed_tree_entry *pte = pe->data;
1250 		struct ibuf *wbuf;
1251 		size_t namelen = strlen(name);
1252 		size_t len = sizeof(struct got_imsg_tree_entry) + namelen;
1253 
1254 		if (len > MAX_IMSGSIZE)
1255 			return got_error(GOT_ERR_NO_SPACE);
1256 
1257 		nimsg++;
1258 		if (totlen + len >= MAX_IMSGSIZE - (IMSG_HEADER_SIZE * nimsg)) {
1259 			err = flush_imsg(ibuf);
1260 			if (err)
1261 				return err;
1262 			nimsg = 0;
1263 		}
1264 
1265 		wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRY, 0, 0, len);
1266 		if (wbuf == NULL)
1267 			return got_error_from_errno("imsg_create TREE_ENTRY");
1268 
1269 		/* Keep in sync with struct got_imsg_tree_object definition! */
1270 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1) {
1271 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1272 			ibuf_free(wbuf);
1273 			return err;
1274 		}
1275 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1) {
1276 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1277 			ibuf_free(wbuf);
1278 			return err;
1279 		}
1280 
1281 		if (imsg_add(wbuf, name, namelen) == -1) {
1282 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1283 			ibuf_free(wbuf);
1284 			return err;
1285 		}
1286 
1287 		wbuf->fd = -1;
1288 		imsg_close(ibuf, wbuf);
1289 
1290 		totlen += len;
1291 	}
1292 
1293 	return flush_imsg(ibuf);
1294 }
1295 
1296 const struct got_error *
1297 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1298 {
1299 	const struct got_error *err = NULL;
1300 	const size_t min_datalen =
1301 	    MIN(sizeof(struct got_imsg_error),
1302 	    sizeof(struct got_imsg_tree_object));
1303 	struct got_imsg_tree_object *itree;
1304 	int nentries = 0;
1305 
1306 	*tree = NULL;
1307 get_more:
1308 	err = read_imsg(ibuf);
1309 	if (err)
1310 		goto done;
1311 
1312 	for (;;) {
1313 		struct imsg imsg;
1314 		size_t n;
1315 		size_t datalen;
1316 		struct got_imsg_tree_entry *ite;
1317 		struct got_tree_entry *te = NULL;
1318 
1319 		n = imsg_get(ibuf, &imsg);
1320 		if (n == 0) {
1321 			if (*tree && (*tree)->nentries != nentries)
1322 				goto get_more;
1323 			break;
1324 		}
1325 
1326 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen)
1327 			return got_error(GOT_ERR_PRIVSEP_LEN);
1328 
1329 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1330 
1331 		switch (imsg.hdr.type) {
1332 		case GOT_IMSG_ERROR:
1333 			err = recv_imsg_error(&imsg, datalen);
1334 			break;
1335 		case GOT_IMSG_TREE:
1336 			/* This message should only appear once. */
1337 			if (*tree != NULL) {
1338 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1339 				break;
1340 			}
1341 			if (datalen != sizeof(*itree)) {
1342 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1343 				break;
1344 			}
1345 			itree = imsg.data;
1346 			*tree = malloc(sizeof(**tree));
1347 			if (*tree == NULL) {
1348 				err = got_error_from_errno("malloc");
1349 				break;
1350 			}
1351 			(*tree)->entries = calloc(itree->nentries,
1352 			    sizeof(struct got_tree_entry));
1353 			if ((*tree)->entries == NULL) {
1354 				err = got_error_from_errno("malloc");
1355 				break;
1356 			}
1357 			(*tree)->nentries = itree->nentries;
1358 			(*tree)->refcnt = 0;
1359 			break;
1360 		case GOT_IMSG_TREE_ENTRY:
1361 			/* This message should be preceeded by GOT_IMSG_TREE. */
1362 			if (*tree == NULL) {
1363 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1364 				break;
1365 			}
1366 			if (datalen < sizeof(*ite) || datalen > MAX_IMSGSIZE) {
1367 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1368 				break;
1369 			}
1370 
1371 			/* Remaining data contains the entry's name. */
1372 			datalen -= sizeof(*ite);
1373 			if (datalen == 0 || datalen > MAX_IMSGSIZE) {
1374 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1375 				break;
1376 			}
1377 			ite = imsg.data;
1378 
1379 			if (datalen + 1 > sizeof(te->name)) {
1380 				err = got_error(GOT_ERR_NO_SPACE);
1381 				break;
1382 			}
1383 			te = &(*tree)->entries[nentries];
1384 			memcpy(te->name, imsg.data + sizeof(*ite), datalen);
1385 			te->name[datalen] = '\0';
1386 
1387 			memcpy(te->id.sha1, ite->id, SHA1_DIGEST_LENGTH);
1388 			te->mode = ite->mode;
1389 			te->idx = nentries;
1390 			nentries++;
1391 			break;
1392 		default:
1393 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1394 			break;
1395 		}
1396 
1397 		imsg_free(&imsg);
1398 	}
1399 done:
1400 	if (*tree && (*tree)->nentries != nentries) {
1401 		if (err == NULL)
1402 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1403 		got_object_tree_close(*tree);
1404 		*tree = NULL;
1405 	}
1406 
1407 	return err;
1408 }
1409 
1410 const struct got_error *
1411 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1412     const uint8_t *data)
1413 {
1414 	struct got_imsg_blob iblob;
1415 
1416 	iblob.size = size;
1417 	iblob.hdrlen = hdrlen;
1418 
1419 	if (data) {
1420 		uint8_t *buf;
1421 
1422 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1423 			return got_error(GOT_ERR_NO_SPACE);
1424 
1425 		buf = malloc(sizeof(iblob) + size);
1426 		if (buf == NULL)
1427 			return got_error_from_errno("malloc");
1428 
1429 		memcpy(buf, &iblob, sizeof(iblob));
1430 		memcpy(buf + sizeof(iblob), data, size);
1431 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1432 		   sizeof(iblob) + size) == -1) {
1433 			free(buf);
1434 			return got_error_from_errno("imsg_compose BLOB");
1435 		}
1436 		free(buf);
1437 	} else {
1438 		/* Data has already been written to file descriptor. */
1439 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1440 		    sizeof(iblob)) == -1)
1441 			return got_error_from_errno("imsg_compose BLOB");
1442 	}
1443 
1444 
1445 	return flush_imsg(ibuf);
1446 }
1447 
1448 const struct got_error *
1449 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1450     struct imsgbuf *ibuf)
1451 {
1452 	const struct got_error *err = NULL;
1453 	struct imsg imsg;
1454 	struct got_imsg_blob *iblob;
1455 	size_t datalen;
1456 
1457 	*outbuf = NULL;
1458 
1459 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1460 	if (err)
1461 		return err;
1462 
1463 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1464 
1465 	switch (imsg.hdr.type) {
1466 	case GOT_IMSG_BLOB:
1467 		if (datalen < sizeof(*iblob)) {
1468 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1469 			break;
1470 		}
1471 		iblob = imsg.data;
1472 		*size = iblob->size;
1473 		*hdrlen = iblob->hdrlen;
1474 
1475 		if (datalen == sizeof(*iblob)) {
1476 			/* Data has been written to file descriptor. */
1477 			break;
1478 		}
1479 
1480 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX) {
1481 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1482 			break;
1483 		}
1484 
1485 		*outbuf = malloc(*size);
1486 		if (*outbuf == NULL) {
1487 			err = got_error_from_errno("malloc");
1488 			break;
1489 		}
1490 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1491 		break;
1492 	default:
1493 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1494 		break;
1495 	}
1496 
1497 	imsg_free(&imsg);
1498 
1499 	return err;
1500 }
1501 
1502 static const struct got_error *
1503 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1504 {
1505 	const struct got_error *err = NULL;
1506 	size_t offset, remain;
1507 
1508 	offset = 0;
1509 	remain = tagmsg_len;
1510 	while (remain > 0) {
1511 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1512 
1513 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1514 		    tag->tagmsg + offset, n) == -1) {
1515 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1516 			break;
1517 		}
1518 
1519 		err = flush_imsg(ibuf);
1520 		if (err)
1521 			break;
1522 
1523 		offset += n;
1524 		remain -= n;
1525 	}
1526 
1527 	return err;
1528 }
1529 
1530 const struct got_error *
1531 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1532 {
1533 	const struct got_error *err = NULL;
1534 	struct got_imsg_tag_object *itag;
1535 	uint8_t *buf;
1536 	size_t len, total;
1537 	size_t tag_len = strlen(tag->tag);
1538 	size_t tagger_len = strlen(tag->tagger);
1539 	size_t tagmsg_len = strlen(tag->tagmsg);
1540 
1541 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1542 
1543 	buf = malloc(total);
1544 	if (buf == NULL)
1545 		return got_error_from_errno("malloc");
1546 
1547 	itag = (struct got_imsg_tag_object *)buf;
1548 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1549 	itag->obj_type = tag->obj_type;
1550 	itag->tag_len = tag_len;
1551 	itag->tagger_len = tagger_len;
1552 	itag->tagger_time = tag->tagger_time;
1553 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1554 	itag->tagmsg_len = tagmsg_len;
1555 
1556 	len = sizeof(*itag);
1557 	memcpy(buf + len, tag->tag, tag_len);
1558 	len += tag_len;
1559 	memcpy(buf + len, tag->tagger, tagger_len);
1560 	len += tagger_len;
1561 
1562 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1563 		err = got_error_from_errno("imsg_compose TAG");
1564 		goto done;
1565 	}
1566 
1567 	if (tagmsg_len == 0 ||
1568 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1569 		err = flush_imsg(ibuf);
1570 		if (err)
1571 			goto done;
1572 	}
1573 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1574 done:
1575 	free(buf);
1576 	return err;
1577 }
1578 
1579 const struct got_error *
1580 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1581 {
1582 	const struct got_error *err = NULL;
1583 	struct imsg imsg;
1584 	struct got_imsg_tag_object *itag;
1585 	size_t len, datalen;
1586 	const size_t min_datalen =
1587 	    MIN(sizeof(struct got_imsg_error),
1588 	    sizeof(struct got_imsg_tag_object));
1589 
1590 	*tag = NULL;
1591 
1592 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1593 	if (err)
1594 		return err;
1595 
1596 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1597 	len = 0;
1598 
1599 	switch (imsg.hdr.type) {
1600 	case GOT_IMSG_TAG:
1601 		if (datalen < sizeof(*itag)) {
1602 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1603 			break;
1604 		}
1605 		itag = imsg.data;
1606 		if (datalen != sizeof(*itag) + itag->tag_len +
1607 		    itag->tagger_len) {
1608 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1609 			break;
1610 		}
1611 		len += sizeof(*itag);
1612 
1613 		*tag = calloc(1, sizeof(**tag));
1614 		if (*tag == NULL) {
1615 			err = got_error_from_errno("calloc");
1616 			break;
1617 		}
1618 
1619 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1620 
1621 		if (itag->tag_len == 0) {
1622 			(*tag)->tag = strdup("");
1623 			if ((*tag)->tag == NULL) {
1624 				err = got_error_from_errno("strdup");
1625 				break;
1626 			}
1627 		} else {
1628 			(*tag)->tag = malloc(itag->tag_len + 1);
1629 			if ((*tag)->tag == NULL) {
1630 				err = got_error_from_errno("malloc");
1631 				break;
1632 			}
1633 			memcpy((*tag)->tag, imsg.data + len,
1634 			    itag->tag_len);
1635 			(*tag)->tag[itag->tag_len] = '\0';
1636 		}
1637 		len += itag->tag_len;
1638 
1639 		(*tag)->obj_type = itag->obj_type;
1640 		(*tag)->tagger_time = itag->tagger_time;
1641 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1642 
1643 		if (itag->tagger_len == 0) {
1644 			(*tag)->tagger = strdup("");
1645 			if ((*tag)->tagger == NULL) {
1646 				err = got_error_from_errno("strdup");
1647 				break;
1648 			}
1649 		} else {
1650 			(*tag)->tagger = malloc(itag->tagger_len + 1);
1651 			if ((*tag)->tagger == NULL) {
1652 				err = got_error_from_errno("malloc");
1653 				break;
1654 			}
1655 			memcpy((*tag)->tagger, imsg.data + len,
1656 			    itag->tagger_len);
1657 			(*tag)->tagger[itag->tagger_len] = '\0';
1658 		}
1659 		len += itag->tagger_len;
1660 
1661 		if (itag->tagmsg_len == 0) {
1662 			(*tag)->tagmsg = strdup("");
1663 			if ((*tag)->tagmsg == NULL) {
1664 				err = got_error_from_errno("strdup");
1665 				break;
1666 			}
1667 		} else {
1668 			size_t offset = 0, remain = itag->tagmsg_len;
1669 
1670 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1671 			if ((*tag)->tagmsg == NULL) {
1672 				err = got_error_from_errno("malloc");
1673 				break;
1674 			}
1675 			while (remain > 0) {
1676 				struct imsg imsg_log;
1677 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1678 				    remain);
1679 
1680 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1681 				if (err)
1682 					return err;
1683 
1684 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1685 					return got_error(GOT_ERR_PRIVSEP_MSG);
1686 
1687 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1688 				    n);
1689 				imsg_free(&imsg_log);
1690 				offset += n;
1691 				remain -= n;
1692 			}
1693 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1694 		}
1695 
1696 		break;
1697 	default:
1698 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1699 		break;
1700 	}
1701 
1702 	imsg_free(&imsg);
1703 
1704 	return err;
1705 }
1706 
1707 const struct got_error *
1708 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1709     struct got_packidx *packidx)
1710 {
1711 	const struct got_error *err = NULL;
1712 	struct got_imsg_packidx ipackidx;
1713 	struct got_imsg_pack ipack;
1714 	int fd;
1715 
1716 	ipackidx.len = packidx->len;
1717 	fd = dup(packidx->fd);
1718 	if (fd == -1)
1719 		return got_error_from_errno("dup");
1720 
1721 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
1722 	    sizeof(ipackidx)) == -1) {
1723 		err = got_error_from_errno("imsg_compose PACKIDX");
1724 		close(fd);
1725 		return err;
1726 	}
1727 
1728 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
1729 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
1730 		return got_error(GOT_ERR_NO_SPACE);
1731 	ipack.filesize = pack->filesize;
1732 
1733 	fd = dup(pack->fd);
1734 	if (fd == -1)
1735 		return got_error_from_errno("dup");
1736 
1737 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
1738 	    == -1) {
1739 		err = got_error_from_errno("imsg_compose PACK");
1740 		close(fd);
1741 		return err;
1742 	}
1743 
1744 	return flush_imsg(ibuf);
1745 }
1746 
1747 const struct got_error *
1748 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
1749     struct got_object_id *id)
1750 {
1751 	struct got_imsg_packed_object iobj;
1752 
1753 	iobj.idx = idx;
1754 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
1755 
1756 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
1757 	    &iobj, sizeof(iobj)) == -1)
1758 		return got_error_from_errno("imsg_compose "
1759 		    "PACKED_OBJECT_REQUEST");
1760 
1761 	return flush_imsg(ibuf);
1762 }
1763 
1764 const struct got_error *
1765 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
1766 {
1767 	const struct got_error *err = NULL;
1768 
1769 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
1770 	    NULL, 0) == -1) {
1771 		err = got_error_from_errno("imsg_compose "
1772 		    "GITCONFIG_PARSE_REQUEST");
1773 		close(fd);
1774 		return err;
1775 	}
1776 
1777 	return flush_imsg(ibuf);
1778 }
1779 
1780 const struct got_error *
1781 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
1782 {
1783 	if (imsg_compose(ibuf,
1784 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
1785 	    NULL, 0) == -1)
1786 		return got_error_from_errno("imsg_compose "
1787 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
1788 
1789 	return flush_imsg(ibuf);
1790 }
1791 
1792 const struct got_error *
1793 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
1794 {
1795 	if (imsg_compose(ibuf,
1796 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
1797 		return got_error_from_errno("imsg_compose "
1798 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
1799 
1800 	return flush_imsg(ibuf);
1801 }
1802 
1803 const struct got_error *
1804 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
1805 {
1806 	if (imsg_compose(ibuf,
1807 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
1808 		return got_error_from_errno("imsg_compose "
1809 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
1810 
1811 	return flush_imsg(ibuf);
1812 }
1813 
1814 const struct got_error *
1815 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
1816 {
1817 	if (imsg_compose(ibuf,
1818 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
1819 		return got_error_from_errno("imsg_compose "
1820 		    "GITCONFIG_REMOTE_REQUEST");
1821 
1822 	return flush_imsg(ibuf);
1823 }
1824 
1825 const struct got_error *
1826 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
1827 {
1828 	if (imsg_compose(ibuf,
1829 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
1830 		return got_error_from_errno("imsg_compose "
1831 		    "GITCONFIG_OWNER_REQUEST");
1832 
1833 	return flush_imsg(ibuf);
1834 }
1835 
1836 const struct got_error *
1837 got_privsep_send_gitconfig_str(struct imsgbuf *ibuf, const char *value)
1838 {
1839 	size_t len = value ? strlen(value) + 1 : 0;
1840 
1841 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_STR_VAL, 0, 0, -1,
1842 	    value, len) == -1)
1843 		return got_error_from_errno("imsg_compose GITCONFIG_STR_VAL");
1844 
1845 	return flush_imsg(ibuf);
1846 }
1847 
1848 const struct got_error *
1849 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
1850 {
1851 	const struct got_error *err = NULL;
1852 	struct imsg imsg;
1853 	size_t datalen;
1854 	const size_t min_datalen = 0;
1855 
1856 	*str = NULL;
1857 
1858 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1859 	if (err)
1860 		return err;
1861 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1862 
1863 	switch (imsg.hdr.type) {
1864 	case GOT_IMSG_GITCONFIG_STR_VAL:
1865 		if (datalen == 0)
1866 			break;
1867 		*str = malloc(datalen);
1868 		if (*str == NULL) {
1869 			err = got_error_from_errno("malloc");
1870 			break;
1871 		}
1872 		if (strlcpy(*str, imsg.data, datalen) >= datalen)
1873 			err = got_error(GOT_ERR_NO_SPACE);
1874 		break;
1875 	default:
1876 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1877 		break;
1878 	}
1879 
1880 	imsg_free(&imsg);
1881 	return err;
1882 }
1883 
1884 const struct got_error *
1885 got_privsep_send_gitconfig_int(struct imsgbuf *ibuf, int value)
1886 {
1887 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_INT_VAL, 0, 0, -1,
1888 	    &value, sizeof(value)) == -1)
1889 		return got_error_from_errno("imsg_compose GITCONFIG_INT_VAL");
1890 
1891 	return flush_imsg(ibuf);
1892 }
1893 
1894 const struct got_error *
1895 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
1896 {
1897 	const struct got_error *err = NULL;
1898 	struct imsg imsg;
1899 	size_t datalen;
1900 	const size_t min_datalen =
1901 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
1902 
1903 	*val = 0;
1904 
1905 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1906 	if (err)
1907 		return err;
1908 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1909 
1910 	switch (imsg.hdr.type) {
1911 	case GOT_IMSG_GITCONFIG_INT_VAL:
1912 		if (datalen != sizeof(*val)) {
1913 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1914 			break;
1915 		}
1916 		memcpy(val, imsg.data, sizeof(*val));
1917 		break;
1918 	default:
1919 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1920 		break;
1921 	}
1922 
1923 	imsg_free(&imsg);
1924 	return err;
1925 }
1926 
1927 const struct got_error *
1928 got_privsep_send_gitconfig_remotes(struct imsgbuf *ibuf,
1929     struct got_remote_repo *remotes, int nremotes)
1930 {
1931 	const struct got_error *err = NULL;
1932 	struct got_imsg_remotes iremotes;
1933 	int i;
1934 
1935 	iremotes.nremotes = nremotes;
1936 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_REMOTES, 0, 0, -1,
1937 	    &iremotes, sizeof(iremotes)) == -1)
1938 		return got_error_from_errno("imsg_compose GITCONFIG_REMOTES");
1939 
1940 	err = flush_imsg(ibuf);
1941 	imsg_clear(ibuf);
1942 	if (err)
1943 		return err;
1944 
1945 	for (i = 0; i < nremotes; i++) {
1946 		struct got_imsg_remote iremote;
1947 		size_t len = sizeof(iremote);
1948 		struct ibuf *wbuf;
1949 
1950 		iremote.mirror_references = remotes[i].mirror_references;
1951 		iremote.name_len = strlen(remotes[i].name);
1952 		len += iremote.name_len;
1953 		iremote.url_len = strlen(remotes[i].url);
1954 		len += iremote.url_len;
1955 
1956 		wbuf = imsg_create(ibuf, GOT_IMSG_GITCONFIG_REMOTE, 0, 0, len);
1957 		if (wbuf == NULL)
1958 			return got_error_from_errno(
1959 			    "imsg_create GITCONFIG_REMOTE");
1960 
1961 		if (imsg_add(wbuf, &iremote, sizeof(iremote)) == -1) {
1962 			err = got_error_from_errno(
1963 			    "imsg_add GITCONFIG_REMOTE");
1964 			ibuf_free(wbuf);
1965 			return err;
1966 		}
1967 
1968 		if (imsg_add(wbuf, remotes[i].name, iremote.name_len) == -1) {
1969 			err = got_error_from_errno(
1970 			    "imsg_add GITCONFIG_REMOTE");
1971 			ibuf_free(wbuf);
1972 			return err;
1973 		}
1974 		if (imsg_add(wbuf, remotes[i].url, iremote.url_len) == -1) {
1975 			err = got_error_from_errno(
1976 			    "imsg_add GITCONFIG_REMOTE");
1977 			ibuf_free(wbuf);
1978 			return err;
1979 		}
1980 
1981 		wbuf->fd = -1;
1982 		imsg_close(ibuf, wbuf);
1983 		err = flush_imsg(ibuf);
1984 		if (err)
1985 			return err;
1986 	}
1987 
1988 	return NULL;
1989 }
1990 
1991 const struct got_error *
1992 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
1993     int *nremotes, struct imsgbuf *ibuf)
1994 {
1995 	const struct got_error *err = NULL;
1996 	struct imsg imsg;
1997 	size_t datalen;
1998 	struct got_imsg_remotes iremotes;
1999 	struct got_imsg_remote iremote;
2000 
2001 	*remotes = NULL;
2002 	*nremotes = 0;
2003 	iremotes.nremotes = 0;
2004 
2005 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
2006 	if (err)
2007 		return err;
2008 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2009 
2010 	switch (imsg.hdr.type) {
2011 	case GOT_IMSG_GITCONFIG_REMOTES:
2012 		if (datalen != sizeof(iremotes)) {
2013 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2014 			break;
2015 		}
2016 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2017 		if (iremotes.nremotes == 0) {
2018 			imsg_free(&imsg);
2019 			return NULL;
2020 		}
2021 		break;
2022 	default:
2023 		imsg_free(&imsg);
2024 		return got_error(GOT_ERR_PRIVSEP_MSG);
2025 	}
2026 
2027 	imsg_free(&imsg);
2028 
2029 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2030 	if (*remotes == NULL)
2031 		return got_error_from_errno("recallocarray");
2032 
2033 	while (*nremotes < iremotes.nremotes) {
2034 		struct got_remote_repo *remote;
2035 	
2036 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
2037 		if (err)
2038 			break;
2039 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2040 
2041 		switch (imsg.hdr.type) {
2042 		case GOT_IMSG_GITCONFIG_REMOTE:
2043 			remote = &(*remotes)[*nremotes];
2044 			if (datalen < sizeof(iremote)) {
2045 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2046 				break;
2047 			}
2048 			memcpy(&iremote, imsg.data, sizeof(iremote));
2049 			if (iremote.name_len == 0 || iremote.url_len == 0 ||
2050 			    (sizeof(iremote) + iremote.name_len +
2051 			    iremote.url_len) > datalen) {
2052 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2053 				break;
2054 			}
2055 			remote->name = strndup(imsg.data + sizeof(iremote),
2056 			    iremote.name_len);
2057 			if (remote->name == NULL) {
2058 				err = got_error_from_errno("strndup");
2059 				break;
2060 			}
2061 			remote->url = strndup(imsg.data + sizeof(iremote) +
2062 			    iremote.name_len, iremote.url_len);
2063 			if (remote->url == NULL) {
2064 				err = got_error_from_errno("strndup");
2065 				free(remote->name);
2066 				break;
2067 			}
2068 			remote->mirror_references = iremote.mirror_references;
2069 			(*nremotes)++;
2070 			break;
2071 		default:
2072 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2073 			break;
2074 		}
2075 
2076 		imsg_free(&imsg);
2077 		if (err)
2078 			break;
2079 	}
2080 
2081 	if (err) {
2082 		int i;
2083 		for (i = 0; i < *nremotes; i++) {
2084 			free((*remotes)[i].name);
2085 			free((*remotes)[i].url);
2086 		}
2087 		free(*remotes);
2088 		*remotes = NULL;
2089 		*nremotes = 0;
2090 	}
2091 	return err;
2092 }
2093 
2094 const struct got_error *
2095 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
2096      struct got_object_id *id, int idx, const char *path)
2097 {
2098 	const struct got_error *err = NULL;
2099 	struct ibuf *wbuf;
2100 	size_t path_len = strlen(path) + 1;
2101 
2102 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
2103 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
2104 	if (wbuf == NULL)
2105 		return got_error_from_errno(
2106 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
2107 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
2108 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2109 		ibuf_free(wbuf);
2110 		return err;
2111 	}
2112 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1) {
2113 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2114 		ibuf_free(wbuf);
2115 		return err;
2116 	}
2117 	if (imsg_add(wbuf, path, path_len) == -1) {
2118 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2119 		ibuf_free(wbuf);
2120 		return err;
2121 	}
2122 
2123 	wbuf->fd = -1;
2124 	imsg_close(ibuf, wbuf);
2125 
2126 	return flush_imsg(ibuf);
2127 }
2128 
2129 const struct got_error *
2130 got_privsep_send_traversed_commits(struct got_object_id *commit_ids, 
2131     size_t ncommits, struct imsgbuf *ibuf)
2132 {
2133 	const struct got_error *err;
2134 	struct ibuf *wbuf;
2135 	int i;
2136 
2137 	wbuf = imsg_create(ibuf, GOT_IMSG_TRAVERSED_COMMITS, 0, 0,
2138 	    sizeof(struct got_imsg_traversed_commits) +
2139 	    ncommits * SHA1_DIGEST_LENGTH);
2140 	if (wbuf == NULL)
2141 		return got_error_from_errno("imsg_create TRAVERSED_COMMITS");
2142 
2143 	if (imsg_add(wbuf, &ncommits, sizeof(ncommits)) == -1) {
2144 		err = got_error_from_errno("imsg_add TRAVERSED_COMMITS");
2145 		ibuf_free(wbuf);
2146 		return err;
2147 	}
2148 	for (i = 0; i < ncommits; i++) {
2149 		struct got_object_id *id = &commit_ids[i];
2150 		if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
2151 			err = got_error_from_errno(
2152 			    "imsg_add TRAVERSED_COMMITS");
2153 			ibuf_free(wbuf);
2154 			return err;
2155 		}
2156 	}
2157 
2158 	wbuf->fd = -1;
2159 	imsg_close(ibuf, wbuf);
2160 
2161 	return flush_imsg(ibuf);
2162 }
2163 
2164 const struct got_error *
2165 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
2166     struct got_object_id **changed_commit_id,
2167     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
2168 {
2169 	const struct got_error *err = NULL;
2170 	struct imsg imsg;
2171 	struct got_imsg_traversed_commits *icommits;
2172 	size_t datalen;
2173 	int i, done = 0;
2174 
2175 	*changed_commit = NULL;
2176 	*changed_commit_id = NULL;
2177 
2178 	while (!done) {
2179 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2180 		if (err)
2181 			return err;
2182 
2183 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2184 		switch (imsg.hdr.type) {
2185 		case GOT_IMSG_TRAVERSED_COMMITS:
2186 			icommits = imsg.data;
2187 			if (datalen != sizeof(*icommits) +
2188 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
2189 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2190 				break;
2191 			}
2192 			for (i = 0; i < icommits->ncommits; i++) {
2193 				struct got_object_qid *qid;
2194 				uint8_t *sha1 = (uint8_t *)imsg.data +
2195 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
2196 				err = got_object_qid_alloc_partial(&qid);
2197 				if (err)
2198 					break;
2199 				memcpy(qid->id->sha1, sha1, SHA1_DIGEST_LENGTH);
2200 				SIMPLEQ_INSERT_TAIL(commit_ids, qid, entry);
2201 
2202 				/* The last commit may contain a change. */
2203 				if (i == icommits->ncommits - 1) {
2204 					*changed_commit_id =
2205 					    got_object_id_dup(qid->id);
2206 					if (*changed_commit_id == NULL) {
2207 						err = got_error_from_errno(
2208 						    "got_object_id_dup");
2209 						break;
2210 					}
2211 				}
2212 			}
2213 			break;
2214 		case GOT_IMSG_COMMIT:
2215 			if (*changed_commit_id == NULL) {
2216 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2217 				break;
2218 			}
2219 			err = get_commit_from_imsg(changed_commit, &imsg,
2220 			    datalen, ibuf);
2221 			break;
2222 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
2223 			done = 1;
2224 			break;
2225 		default:
2226 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2227 			break;
2228 		}
2229 
2230 		imsg_free(&imsg);
2231 		if (err)
2232 			break;
2233 	}
2234 
2235 	if (err)
2236 		got_object_id_queue_free(commit_ids);
2237 	return err;
2238 }
2239 
2240 const struct got_error *
2241 got_privsep_send_commit_traversal_done(struct imsgbuf *ibuf)
2242 {
2243 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_DONE, 0, 0, -1,
2244 	    NULL, 0) == -1)
2245 		return got_error_from_errno("imsg_compose TRAVERSAL_DONE");
2246 
2247 	return flush_imsg(ibuf);
2248 }
2249 
2250 const struct got_error *
2251 got_privsep_unveil_exec_helpers(void)
2252 {
2253 	const char *helpers[] = {
2254 	    GOT_PATH_PROG_READ_PACK,
2255 	    GOT_PATH_PROG_READ_OBJECT,
2256 	    GOT_PATH_PROG_READ_COMMIT,
2257 	    GOT_PATH_PROG_READ_TREE,
2258 	    GOT_PATH_PROG_READ_BLOB,
2259 	    GOT_PATH_PROG_READ_TAG,
2260 	    GOT_PATH_PROG_READ_GITCONFIG,
2261 	    GOT_PATH_PROG_FETCH_PACK,
2262 	    GOT_PATH_PROG_INDEX_PACK,
2263 	};
2264 	int i;
2265 
2266 	for (i = 0; i < nitems(helpers); i++) {
2267 		if (unveil(helpers[i], "x") == 0)
2268 			continue;
2269 		return got_error_from_errno2("unveil", helpers[i]);
2270 	}
2271 
2272 	return NULL;
2273 }
2274 
2275 void
2276 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
2277 {
2278 	if (close(imsg_fds[0]) != 0) {
2279 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2280 		_exit(1);
2281 	}
2282 
2283 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
2284 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2285 		_exit(1);
2286 	}
2287 	if (closefrom(GOT_IMSG_FD_CHILD + 1) == -1) {
2288 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2289 		_exit(1);
2290 	}
2291 
2292 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
2293 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
2294 		    strerror(errno));
2295 		_exit(1);
2296 	}
2297 }