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Date:: Tue Mar 24 14:08:03 2020 UTC
Message:: represent packfile hash as byte array in the privsep layer, not as object ID
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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_flush_imsg(struct imsgbuf *ibuf)
220 {
221 	return flush_imsg(ibuf);
222 }
223 
224 const struct got_error *
225 got_privsep_send_stop(int fd)
226 {
227 	const struct got_error *err = NULL;
228 	struct imsgbuf ibuf;
229 
230 	imsg_init(&ibuf, fd);
231 
232 	if (imsg_compose(&ibuf, GOT_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
233 		return got_error_from_errno("imsg_compose STOP");
234 
235 	err = flush_imsg(&ibuf);
236 	imsg_clear(&ibuf);
237 	return err;
238 }
239 
240 const struct got_error *
241 got_privsep_send_obj_req(struct imsgbuf *ibuf, int fd)
242 {
243 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_REQUEST, 0, 0, fd, NULL, 0)
244 	    == -1)
245 		return got_error_from_errno("imsg_compose OBJECT_REQUEST");
246 
247 	return flush_imsg(ibuf);
248 }
249 
250 const struct got_error *
251 got_privsep_send_commit_req(struct imsgbuf *ibuf, int fd,
252     struct got_object_id *id, int pack_idx)
253 {
254 	const struct got_error *err = NULL;
255 	struct got_imsg_packed_object iobj, *iobjp;
256 	size_t len;
257 
258 	if (id) { /* commit is packed */
259 		iobj.idx = pack_idx;
260 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
261 		iobjp = &iobj;
262 		len = sizeof(iobj);
263 	} else {
264 		iobjp = NULL;
265 		len = 0;
266 	}
267 
268 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_REQUEST, 0, 0, fd, iobjp, len)
269 	    == -1) {
270 		err = got_error_from_errno("imsg_compose COMMIT_REQUEST");
271 		close(fd);
272 		return err;
273 	}
274 
275 	return flush_imsg(ibuf);
276 }
277 
278 const struct got_error *
279 got_privsep_send_tree_req(struct imsgbuf *ibuf, int fd,
280     struct got_object_id *id, int pack_idx)
281 {
282 	const struct got_error *err = NULL;
283 	struct ibuf *wbuf;
284 	size_t len = id ? sizeof(struct got_imsg_packed_object) : 0;
285 
286 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_REQUEST, 0, 0, len);
287 	if (wbuf == NULL)
288 		return got_error_from_errno("imsg_create TREE_REQUEST");
289 
290 	if (id) { /* tree is packed */
291 		if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
292 			err = got_error_from_errno("imsg_add TREE_ENTRY");
293 			ibuf_free(wbuf);
294 			return err;
295 		}
296 
297 		if (imsg_add(wbuf, &pack_idx, sizeof(pack_idx)) == -1) {
298 			err = got_error_from_errno("imsg_add TREE_ENTRY");
299 			ibuf_free(wbuf);
300 			return err;
301 		}
302 	}
303 
304 	wbuf->fd = fd;
305 	imsg_close(ibuf, wbuf);
306 
307 	return flush_imsg(ibuf);
308 }
309 
310 const struct got_error *
311 got_privsep_send_tag_req(struct imsgbuf *ibuf, int fd,
312     struct got_object_id *id, int pack_idx)
313 {
314 	struct got_imsg_packed_object iobj, *iobjp;
315 	size_t len;
316 
317 	if (id) { /* tag is packed */
318 		iobj.idx = pack_idx;
319 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
320 		iobjp = &iobj;
321 		len = sizeof(iobj);
322 	} else {
323 		iobjp = NULL;
324 		len = 0;
325 	}
326 
327 	if (imsg_compose(ibuf, GOT_IMSG_TAG_REQUEST, 0, 0, fd, iobjp, len)
328 	    == -1)
329 		return got_error_from_errno("imsg_compose TAG_REQUEST");
330 
331 	return flush_imsg(ibuf);
332 }
333 
334 const struct got_error *
335 got_privsep_send_blob_req(struct imsgbuf *ibuf, int infd,
336     struct got_object_id *id, int pack_idx)
337 {
338 	const struct got_error *err = NULL;
339 	struct got_imsg_packed_object iobj, *iobjp;
340 	size_t len;
341 
342 	if (id) { /* blob is packed */
343 		iobj.idx = pack_idx;
344 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
345 		iobjp = &iobj;
346 		len = sizeof(iobj);
347 	} else {
348 		iobjp = NULL;
349 		len = 0;
350 	}
351 
352 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_REQUEST, 0, 0, infd, iobjp, len)
353 	    == -1) {
354 		err = got_error_from_errno("imsg_compose BLOB_REQUEST");
355 		close(infd);
356 		return err;
357 	}
358 
359 	return flush_imsg(ibuf);
360 }
361 
362 const struct got_error *
363 got_privsep_send_blob_outfd(struct imsgbuf *ibuf, int outfd)
364 {
365 	const struct got_error *err = NULL;
366 
367 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_OUTFD, 0, 0, outfd, NULL, 0)
368 	    == -1) {
369 		err = got_error_from_errno("imsg_compose BLOB_OUTFD");
370 		close(outfd);
371 		return err;
372 	}
373 
374 	return flush_imsg(ibuf);
375 }
376 
377 static const struct got_error *
378 send_fd(struct imsgbuf *ibuf, int imsg_code, int fd)
379 {
380 	const struct got_error *err = NULL;
381 
382 	if (imsg_compose(ibuf, imsg_code, 0, 0, fd, NULL, 0) == -1) {
383 		err = got_error_from_errno("imsg_compose TMPFD");
384 		close(fd);
385 		return err;
386 	}
387 
388 	return flush_imsg(ibuf);
389 }
390 
391 const struct got_error *
392 got_privsep_send_tmpfd(struct imsgbuf *ibuf, int fd)
393 {
394 	return send_fd(ibuf, GOT_IMSG_TMPFD, fd);
395 }
396 
397 const struct got_error *
398 got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj)
399 {
400 	struct got_imsg_object iobj;
401 
402 	memcpy(iobj.id, obj->id.sha1, sizeof(iobj.id));
403 	iobj.type = obj->type;
404 	iobj.flags = obj->flags;
405 	iobj.hdrlen = obj->hdrlen;
406 	iobj.size = obj->size;
407 	if (iobj.flags & GOT_OBJ_FLAG_PACKED) {
408 		iobj.pack_offset = obj->pack_offset;
409 		iobj.pack_idx = obj->pack_idx;
410 	}
411 
412 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
413 	    == -1)
414 		return got_error_from_errno("imsg_compose OBJECT");
415 
416 	return flush_imsg(ibuf);
417 }
418 
419 const struct got_error *
420 got_privsep_send_fetch_req(struct imsgbuf *ibuf, int fd,
421    struct got_pathlist_head *have_refs, int fetch_all_branches,
422    struct got_pathlist_head *wanted_branches,
423    struct got_pathlist_head *wanted_refs, int list_refs_only, int verbosity)
424 {
425 	const struct got_error *err = NULL;
426 	struct ibuf *wbuf;
427 	size_t len;
428 	struct got_pathlist_entry *pe;
429 	struct got_imsg_fetch_request fetchreq;
430 
431 	memset(&fetchreq, 0, sizeof(fetchreq));
432 	fetchreq.fetch_all_branches = fetch_all_branches;
433 	fetchreq.list_refs_only = list_refs_only;
434 	fetchreq.verbosity = verbosity;
435 	TAILQ_FOREACH(pe, have_refs, entry)
436 		fetchreq.n_have_refs++;
437 	TAILQ_FOREACH(pe, wanted_branches, entry)
438 		fetchreq.n_wanted_branches++;
439 	TAILQ_FOREACH(pe, wanted_refs, entry)
440 		fetchreq.n_wanted_refs++;
441 	len = sizeof(struct got_imsg_fetch_request);
442 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
443 		close(fd);
444 		return got_error(GOT_ERR_NO_SPACE);
445 	}
446 
447 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_REQUEST, 0, 0, fd,
448 	    &fetchreq, sizeof(fetchreq)) == -1)
449 		return got_error_from_errno(
450 		    "imsg_compose FETCH_SERVER_PROGRESS");
451 
452 	err = flush_imsg(ibuf);
453 	if (err) {
454 		close(fd);
455 		return err;
456 	}
457 	fd = -1;
458 
459 	TAILQ_FOREACH(pe, have_refs, entry) {
460 		const char *name = pe->path;
461 		size_t name_len = pe->path_len;
462 		struct got_object_id *id = pe->data;
463 
464 		len = sizeof(struct got_imsg_fetch_have_ref) + name_len;
465 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_HAVE_REF, 0, 0, len);
466 		if (wbuf == NULL)
467 			return got_error_from_errno("imsg_create FETCH_HAVE_REF");
468 
469 		/* Keep in sync with struct got_imsg_fetch_have_ref! */
470 		if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1) {
471 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
472 			ibuf_free(wbuf);
473 			return err;
474 		}
475 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
476 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
477 			ibuf_free(wbuf);
478 			return err;
479 		}
480 		if (imsg_add(wbuf, name, name_len) == -1) {
481 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
482 			ibuf_free(wbuf);
483 			return err;
484 		}
485 
486 		wbuf->fd = -1;
487 		imsg_close(ibuf, wbuf);
488 		err = flush_imsg(ibuf);
489 		if (err)
490 			return err;
491 	}
492 
493 	TAILQ_FOREACH(pe, wanted_branches, entry) {
494 		const char *name = pe->path;
495 		size_t name_len = pe->path_len;
496 
497 		len = sizeof(struct got_imsg_fetch_wanted_branch) + name_len;
498 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_BRANCH, 0, 0,
499 		    len);
500 		if (wbuf == NULL)
501 			return got_error_from_errno(
502 			     "imsg_create FETCH_WANTED_BRANCH");
503 
504 		/* Keep in sync with struct got_imsg_fetch_wanted_branch! */
505 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
506 			err = got_error_from_errno(
507 			    "imsg_add FETCH_WANTED_BRANCH");
508 			ibuf_free(wbuf);
509 			return err;
510 		}
511 		if (imsg_add(wbuf, name, name_len) == -1) {
512 			err = got_error_from_errno(
513 			     "imsg_add FETCH_WANTED_BRANCH");
514 			ibuf_free(wbuf);
515 			return err;
516 		}
517 
518 		wbuf->fd = -1;
519 		imsg_close(ibuf, wbuf);
520 		err = flush_imsg(ibuf);
521 		if (err)
522 			return err;
523 	}
524 
525 	TAILQ_FOREACH(pe, wanted_refs, entry) {
526 		const char *name = pe->path;
527 		size_t name_len = pe->path_len;
528 
529 		len = sizeof(struct got_imsg_fetch_wanted_ref) + name_len;
530 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_REF, 0, 0,
531 		    len);
532 		if (wbuf == NULL)
533 			return got_error_from_errno(
534 			     "imsg_create FETCH_WANTED_REF");
535 
536 		/* Keep in sync with struct got_imsg_fetch_wanted_ref! */
537 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
538 			err = got_error_from_errno(
539 			    "imsg_add FETCH_WANTED_REF");
540 			ibuf_free(wbuf);
541 			return err;
542 		}
543 		if (imsg_add(wbuf, name, name_len) == -1) {
544 			err = got_error_from_errno(
545 			     "imsg_add FETCH_WANTED_REF");
546 			ibuf_free(wbuf);
547 			return err;
548 		}
549 
550 		wbuf->fd = -1;
551 		imsg_close(ibuf, wbuf);
552 		err = flush_imsg(ibuf);
553 		if (err)
554 			return err;
555 	}
556 
557 
558 	return NULL;
559 
560 }
561 
562 const struct got_error *
563 got_privsep_send_fetch_outfd(struct imsgbuf *ibuf, int fd)
564 {
565 	return send_fd(ibuf, GOT_IMSG_FETCH_OUTFD, fd);
566 }
567 
568 const struct got_error *
569 got_privsep_recv_fetch_progress(int *done, struct got_object_id **id,
570     char **refname, struct got_pathlist_head *symrefs, char **server_progress,
571     off_t *packfile_size, uint8_t *pack_sha1, struct imsgbuf *ibuf)
572 {
573 	const struct got_error *err = NULL;
574 	struct imsg imsg;
575 	size_t datalen;
576 	struct got_imsg_fetch_symrefs *isymrefs = NULL;
577 	size_t n, remain;
578 	off_t off;
579 	int i;
580 
581 	*done = 0;
582 	*id = NULL;
583 	*refname = NULL;
584 	*server_progress = NULL;
585 	*packfile_size = 0;
586 	memset(pack_sha1, 0, SHA1_DIGEST_LENGTH);
587 
588 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
589 	if (err)
590 		return err;
591 
592 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
593 	switch (imsg.hdr.type) {
594 	case GOT_IMSG_ERROR:
595 		if (datalen < sizeof(struct got_imsg_error)) {
596 			err = got_error(GOT_ERR_PRIVSEP_LEN);
597 			break;
598 		}
599 		err = recv_imsg_error(&imsg, datalen);
600 		break;
601 	case GOT_IMSG_FETCH_SYMREFS:
602 		if (datalen < sizeof(*isymrefs)) {
603 			err = got_error(GOT_ERR_PRIVSEP_LEN);
604 			break;
605 		}
606 		if (isymrefs != NULL) {
607 			err = got_error(GOT_ERR_PRIVSEP_MSG);
608 			break;
609 		}
610 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
611 		off = sizeof(*isymrefs);
612 		remain = datalen - off;
613 		for (n = 0; n < isymrefs->nsymrefs; n++) {
614 			struct got_imsg_fetch_symref *s;
615 			char *name, *target;
616 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
617 				err = got_error(GOT_ERR_PRIVSEP_LEN);
618 				goto done;
619 			}
620 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
621 			off += sizeof(*s);
622 			remain -= sizeof(*s);
623 			if (remain < s->name_len) {
624 				err = got_error(GOT_ERR_PRIVSEP_LEN);
625 				goto done;
626 			}
627 			name = strndup(imsg.data + off, s->name_len);
628 			if (name == NULL) {
629 				err = got_error_from_errno("strndup");
630 				goto done;
631 			}
632 			off += s->name_len;
633 			remain -= s->name_len;
634 			if (remain < s->target_len) {
635 				err = got_error(GOT_ERR_PRIVSEP_LEN);
636 				free(name);
637 				goto done;
638 			}
639 			target = strndup(imsg.data + off, s->target_len);
640 			if (target == NULL) {
641 				err = got_error_from_errno("strndup");
642 				free(name);
643 				goto done;
644 			}
645 			off += s->target_len;
646 			remain -= s->target_len;
647 			err = got_pathlist_append(symrefs, name, target);
648 			if (err) {
649 				free(name);
650 				free(target);
651 				goto done;
652 			}
653 		}
654 		break;
655 	case GOT_IMSG_FETCH_REF:
656 		if (datalen <= SHA1_DIGEST_LENGTH) {
657 			err = got_error(GOT_ERR_PRIVSEP_MSG);
658 			break;
659 		}
660 		*id = malloc(sizeof(**id));
661 		if (*id == NULL) {
662 			err = got_error_from_errno("malloc");
663 			break;
664 		}
665 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
666 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
667 		    datalen - SHA1_DIGEST_LENGTH);
668 		if (*refname == NULL) {
669 			err = got_error_from_errno("strndup");
670 			break;
671 		}
672 		break;
673 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
674 		if (datalen == 0) {
675 			err = got_error(GOT_ERR_PRIVSEP_LEN);
676 			break;
677 		}
678 		*server_progress = strndup(imsg.data, datalen);
679 		if (*server_progress == NULL) {
680 			err = got_error_from_errno("strndup");
681 			break;
682 		}
683 		for (i = 0; i < datalen; i++) {
684 			if (!isprint((unsigned char)(*server_progress)[i]) &&
685 			    !isspace((unsigned char)(*server_progress)[i])) {
686 				err = got_error(GOT_ERR_PRIVSEP_MSG);
687 				free(*server_progress);
688 				*server_progress = NULL;
689 				goto done;
690 			}
691 		}
692 		break;
693 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
694 		if (datalen < sizeof(*packfile_size)) {
695 			err = got_error(GOT_ERR_PRIVSEP_MSG);
696 			break;
697 		}
698 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
699 		break;
700 	case GOT_IMSG_FETCH_DONE:
701 		if (datalen != SHA1_DIGEST_LENGTH) {
702 			err = got_error(GOT_ERR_PRIVSEP_MSG);
703 			break;
704 		}
705 		memcpy(pack_sha1, imsg.data, SHA1_DIGEST_LENGTH);
706 		*done = 1;
707 		break;
708 	default:
709 		err = got_error(GOT_ERR_PRIVSEP_MSG);
710 		break;
711 	}
712 done:
713 	if (err) {
714 		free(*id);
715 		*id = NULL;
716 		free(*refname);
717 		*refname = NULL;
718 	}
719 	imsg_free(&imsg);
720 	return err;
721 }
722 
723 const struct got_error *
724 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_sha1,
725     int fd)
726 {
727 	const struct got_error *err = NULL;
728 
729 	/* Keep in sync with struct got_imsg_index_pack_request */
730 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
731 	    pack_sha1, SHA1_DIGEST_LENGTH) == -1) {
732 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
733 		close(fd);
734 		return err;
735 	}
736 	return flush_imsg(ibuf);
737 }
738 
739 const struct got_error *
740 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
741 {
742 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
743 }
744 
745 const struct got_error *
746 got_privsep_recv_index_progress(int *done, int *nobj_total,
747     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
748     struct imsgbuf *ibuf)
749 {
750 	const struct got_error *err = NULL;
751 	struct imsg imsg;
752 	struct got_imsg_index_pack_progress *iprogress;
753 	size_t datalen;
754 
755 	*done = 0;
756 	*nobj_total = 0;
757 	*nobj_indexed = 0;
758 	*nobj_resolved = 0;
759 
760 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
761 	if (err)
762 		return err;
763 
764 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
765 	switch (imsg.hdr.type) {
766 	case GOT_IMSG_ERROR:
767 		if (datalen < sizeof(struct got_imsg_error)) {
768 			err = got_error(GOT_ERR_PRIVSEP_LEN);
769 			break;
770 		}
771 		err = recv_imsg_error(&imsg, datalen);
772 		break;
773 	case GOT_IMSG_IDXPACK_PROGRESS:
774 		if (datalen < sizeof(*iprogress)) {
775 			err = got_error(GOT_ERR_PRIVSEP_LEN);
776 			break;
777 		}
778 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
779 		*nobj_total = iprogress->nobj_total;
780 		*nobj_indexed = iprogress->nobj_indexed;
781 		*nobj_loose = iprogress->nobj_loose;
782 		*nobj_resolved = iprogress->nobj_resolved;
783 		break;
784 	case GOT_IMSG_IDXPACK_DONE:
785 		if (datalen != 0) {
786 			err = got_error(GOT_ERR_PRIVSEP_LEN);
787 			break;
788 		}
789 		*done = 1;
790 		break;
791 	default:
792 		err = got_error(GOT_ERR_PRIVSEP_MSG);
793 		break;
794 	}
795 
796 	imsg_free(&imsg);
797 	return err;
798 }
799 
800 const struct got_error *
801 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
802     struct imsgbuf *ibuf)
803 {
804 	const struct got_error *err = NULL;
805 	struct got_imsg_object *iobj;
806 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
807 
808 	if (datalen != sizeof(*iobj))
809 		return got_error(GOT_ERR_PRIVSEP_LEN);
810 	iobj = imsg->data;
811 
812 	*obj = calloc(1, sizeof(**obj));
813 	if (*obj == NULL)
814 		return got_error_from_errno("calloc");
815 
816 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
817 	(*obj)->type = iobj->type;
818 	(*obj)->flags = iobj->flags;
819 	(*obj)->hdrlen = iobj->hdrlen;
820 	(*obj)->size = iobj->size;
821 	/* path_packfile is handled by caller */
822 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
823 		(*obj)->pack_offset = iobj->pack_offset;
824 		(*obj)->pack_idx = iobj->pack_idx;
825 	}
826 
827 	return err;
828 }
829 
830 const struct got_error *
831 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
832 {
833 	const struct got_error *err = NULL;
834 	struct imsg imsg;
835 	const size_t min_datalen =
836 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
837 
838 	*obj = NULL;
839 
840 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
841 	if (err)
842 		return err;
843 
844 	switch (imsg.hdr.type) {
845 	case GOT_IMSG_OBJECT:
846 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
847 		break;
848 	default:
849 		err = got_error(GOT_ERR_PRIVSEP_MSG);
850 		break;
851 	}
852 
853 	imsg_free(&imsg);
854 
855 	return err;
856 }
857 
858 static const struct got_error *
859 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
860     size_t logmsg_len)
861 {
862 	const struct got_error *err = NULL;
863 	size_t offset, remain;
864 
865 	offset = 0;
866 	remain = logmsg_len;
867 	while (remain > 0) {
868 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
869 
870 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
871 		    commit->logmsg + offset, n) == -1) {
872 			err = got_error_from_errno("imsg_compose "
873 			    "COMMIT_LOGMSG");
874 			break;
875 		}
876 
877 		err = flush_imsg(ibuf);
878 		if (err)
879 			break;
880 
881 		offset += n;
882 		remain -= n;
883 	}
884 
885 	return err;
886 }
887 
888 const struct got_error *
889 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
890 {
891 	const struct got_error *err = NULL;
892 	struct got_imsg_commit_object *icommit;
893 	uint8_t *buf;
894 	size_t len, total;
895 	struct got_object_qid *qid;
896 	size_t author_len = strlen(commit->author);
897 	size_t committer_len = strlen(commit->committer);
898 	size_t logmsg_len = strlen(commit->logmsg);
899 
900 	total = sizeof(*icommit) + author_len + committer_len +
901 	    commit->nparents * SHA1_DIGEST_LENGTH;
902 
903 	buf = malloc(total);
904 	if (buf == NULL)
905 		return got_error_from_errno("malloc");
906 
907 	icommit = (struct got_imsg_commit_object *)buf;
908 	memcpy(icommit->tree_id, commit->tree_id->sha1,
909 	    sizeof(icommit->tree_id));
910 	icommit->author_len = author_len;
911 	icommit->author_time = commit->author_time;
912 	icommit->author_gmtoff = commit->author_gmtoff;
913 	icommit->committer_len = committer_len;
914 	icommit->committer_time = commit->committer_time;
915 	icommit->committer_gmtoff = commit->committer_gmtoff;
916 	icommit->logmsg_len = logmsg_len;
917 	icommit->nparents = commit->nparents;
918 
919 	len = sizeof(*icommit);
920 	memcpy(buf + len, commit->author, author_len);
921 	len += author_len;
922 	memcpy(buf + len, commit->committer, committer_len);
923 	len += committer_len;
924 	SIMPLEQ_FOREACH(qid, &commit->parent_ids, entry) {
925 		memcpy(buf + len, qid->id, SHA1_DIGEST_LENGTH);
926 		len += SHA1_DIGEST_LENGTH;
927 	}
928 
929 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
930 		err = got_error_from_errno("imsg_compose COMMIT");
931 		goto done;
932 	}
933 
934 	if (logmsg_len == 0 ||
935 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
936 		err = flush_imsg(ibuf);
937 		if (err)
938 			goto done;
939 	}
940 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
941 done:
942 	free(buf);
943 	return err;
944 }
945 
946 static const struct got_error *
947 get_commit_from_imsg(struct got_commit_object **commit,
948     struct imsg *imsg, size_t datalen, struct imsgbuf *ibuf)
949 {
950 	const struct got_error *err = NULL;
951 	struct got_imsg_commit_object *icommit;
952 	size_t len = 0;
953 	int i;
954 
955 	if (datalen < sizeof(*icommit))
956 		return got_error(GOT_ERR_PRIVSEP_LEN);
957 
958 	icommit = imsg->data;
959 	if (datalen != sizeof(*icommit) + icommit->author_len +
960 	    icommit->committer_len +
961 	    icommit->nparents * SHA1_DIGEST_LENGTH)
962 		return got_error(GOT_ERR_PRIVSEP_LEN);
963 
964 	if (icommit->nparents < 0)
965 		return got_error(GOT_ERR_PRIVSEP_LEN);
966 
967 	len += sizeof(*icommit);
968 
969 	*commit = got_object_commit_alloc_partial();
970 	if (*commit == NULL)
971 		return got_error_from_errno(
972 		    "got_object_commit_alloc_partial");
973 
974 	memcpy((*commit)->tree_id->sha1, icommit->tree_id,
975 	    SHA1_DIGEST_LENGTH);
976 	(*commit)->author_time = icommit->author_time;
977 	(*commit)->author_gmtoff = icommit->author_gmtoff;
978 	(*commit)->committer_time = icommit->committer_time;
979 	(*commit)->committer_gmtoff = icommit->committer_gmtoff;
980 
981 	if (icommit->author_len == 0) {
982 		(*commit)->author = strdup("");
983 		if ((*commit)->author == NULL) {
984 			err = got_error_from_errno("strdup");
985 			goto done;
986 		}
987 	} else {
988 		(*commit)->author = malloc(icommit->author_len + 1);
989 		if ((*commit)->author == NULL) {
990 			err = got_error_from_errno("malloc");
991 			goto done;
992 		}
993 		memcpy((*commit)->author, imsg->data + len,
994 		    icommit->author_len);
995 		(*commit)->author[icommit->author_len] = '\0';
996 	}
997 	len += icommit->author_len;
998 
999 	if (icommit->committer_len == 0) {
1000 		(*commit)->committer = strdup("");
1001 		if ((*commit)->committer == NULL) {
1002 			err = got_error_from_errno("strdup");
1003 			goto done;
1004 		}
1005 	} else {
1006 		(*commit)->committer =
1007 		    malloc(icommit->committer_len + 1);
1008 		if ((*commit)->committer == NULL) {
1009 			err = got_error_from_errno("malloc");
1010 			goto done;
1011 		}
1012 		memcpy((*commit)->committer, imsg->data + len,
1013 		    icommit->committer_len);
1014 		(*commit)->committer[icommit->committer_len] = '\0';
1015 	}
1016 	len += icommit->committer_len;
1017 
1018 	if (icommit->logmsg_len == 0) {
1019 		(*commit)->logmsg = strdup("");
1020 		if ((*commit)->logmsg == NULL) {
1021 			err = got_error_from_errno("strdup");
1022 			goto done;
1023 		}
1024 	} else {
1025 		size_t offset = 0, remain = icommit->logmsg_len;
1026 
1027 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1028 		if ((*commit)->logmsg == NULL) {
1029 			err = got_error_from_errno("malloc");
1030 			goto done;
1031 		}
1032 		while (remain > 0) {
1033 			struct imsg imsg_log;
1034 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1035 			    remain);
1036 
1037 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1038 			if (err)
1039 				goto done;
1040 
1041 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1042 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1043 				goto done;
1044 			}
1045 
1046 			memcpy((*commit)->logmsg + offset,
1047 			    imsg_log.data, n);
1048 			imsg_free(&imsg_log);
1049 			offset += n;
1050 			remain -= n;
1051 		}
1052 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1053 	}
1054 
1055 	for (i = 0; i < icommit->nparents; i++) {
1056 		struct got_object_qid *qid;
1057 
1058 		err = got_object_qid_alloc_partial(&qid);
1059 		if (err)
1060 			break;
1061 		memcpy(qid->id, imsg->data + len +
1062 		    i * SHA1_DIGEST_LENGTH, sizeof(*qid->id));
1063 		SIMPLEQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1064 		(*commit)->nparents++;
1065 	}
1066 done:
1067 	if (err) {
1068 		got_object_commit_close(*commit);
1069 		*commit = NULL;
1070 	}
1071 	return err;
1072 }
1073 
1074 const struct got_error *
1075 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1076 {
1077 	const struct got_error *err = NULL;
1078 	struct imsg imsg;
1079 	size_t datalen;
1080 	const size_t min_datalen =
1081 	    MIN(sizeof(struct got_imsg_error),
1082 	    sizeof(struct got_imsg_commit_object));
1083 
1084 	*commit = NULL;
1085 
1086 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1087 	if (err)
1088 		return err;
1089 
1090 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1091 
1092 	switch (imsg.hdr.type) {
1093 	case GOT_IMSG_COMMIT:
1094 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1095 		break;
1096 	default:
1097 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1098 		break;
1099 	}
1100 
1101 	imsg_free(&imsg);
1102 
1103 	return err;
1104 }
1105 
1106 const struct got_error *
1107 got_privsep_send_tree(struct imsgbuf *ibuf, struct got_pathlist_head *entries,
1108     int nentries)
1109 {
1110 	const struct got_error *err = NULL;
1111 	struct got_imsg_tree_object itree;
1112 	struct got_pathlist_entry *pe;
1113 	size_t totlen;
1114 	int nimsg; /* number of imsg queued in ibuf */
1115 
1116 	itree.nentries = nentries;
1117 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1118 	    == -1)
1119 		return got_error_from_errno("imsg_compose TREE");
1120 
1121 	totlen = sizeof(itree);
1122 	nimsg = 1;
1123 	TAILQ_FOREACH(pe, entries, entry) {
1124 		const char *name = pe->path;
1125 		struct got_parsed_tree_entry *pte = pe->data;
1126 		struct ibuf *wbuf;
1127 		size_t namelen = strlen(name);
1128 		size_t len = sizeof(struct got_imsg_tree_entry) + namelen;
1129 
1130 		if (len > MAX_IMSGSIZE)
1131 			return got_error(GOT_ERR_NO_SPACE);
1132 
1133 		nimsg++;
1134 		if (totlen + len >= MAX_IMSGSIZE - (IMSG_HEADER_SIZE * nimsg)) {
1135 			err = flush_imsg(ibuf);
1136 			if (err)
1137 				return err;
1138 			nimsg = 0;
1139 		}
1140 
1141 		wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRY, 0, 0, len);
1142 		if (wbuf == NULL)
1143 			return got_error_from_errno("imsg_create TREE_ENTRY");
1144 
1145 		/* Keep in sync with struct got_imsg_tree_object definition! */
1146 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1) {
1147 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1148 			ibuf_free(wbuf);
1149 			return err;
1150 		}
1151 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1) {
1152 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1153 			ibuf_free(wbuf);
1154 			return err;
1155 		}
1156 
1157 		if (imsg_add(wbuf, name, namelen) == -1) {
1158 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1159 			ibuf_free(wbuf);
1160 			return err;
1161 		}
1162 
1163 		wbuf->fd = -1;
1164 		imsg_close(ibuf, wbuf);
1165 
1166 		totlen += len;
1167 	}
1168 
1169 	return flush_imsg(ibuf);
1170 }
1171 
1172 const struct got_error *
1173 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1174 {
1175 	const struct got_error *err = NULL;
1176 	const size_t min_datalen =
1177 	    MIN(sizeof(struct got_imsg_error),
1178 	    sizeof(struct got_imsg_tree_object));
1179 	struct got_imsg_tree_object *itree;
1180 	int nentries = 0;
1181 
1182 	*tree = NULL;
1183 get_more:
1184 	err = read_imsg(ibuf);
1185 	if (err)
1186 		goto done;
1187 
1188 	for (;;) {
1189 		struct imsg imsg;
1190 		size_t n;
1191 		size_t datalen;
1192 		struct got_imsg_tree_entry *ite;
1193 		struct got_tree_entry *te = NULL;
1194 
1195 		n = imsg_get(ibuf, &imsg);
1196 		if (n == 0) {
1197 			if (*tree && (*tree)->nentries != nentries)
1198 				goto get_more;
1199 			break;
1200 		}
1201 
1202 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen)
1203 			return got_error(GOT_ERR_PRIVSEP_LEN);
1204 
1205 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1206 
1207 		switch (imsg.hdr.type) {
1208 		case GOT_IMSG_ERROR:
1209 			err = recv_imsg_error(&imsg, datalen);
1210 			break;
1211 		case GOT_IMSG_TREE:
1212 			/* This message should only appear once. */
1213 			if (*tree != NULL) {
1214 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1215 				break;
1216 			}
1217 			if (datalen != sizeof(*itree)) {
1218 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1219 				break;
1220 			}
1221 			itree = imsg.data;
1222 			*tree = malloc(sizeof(**tree));
1223 			if (*tree == NULL) {
1224 				err = got_error_from_errno("malloc");
1225 				break;
1226 			}
1227 			(*tree)->entries = calloc(itree->nentries,
1228 			    sizeof(struct got_tree_entry));
1229 			if ((*tree)->entries == NULL) {
1230 				err = got_error_from_errno("malloc");
1231 				break;
1232 			}
1233 			(*tree)->nentries = itree->nentries;
1234 			(*tree)->refcnt = 0;
1235 			break;
1236 		case GOT_IMSG_TREE_ENTRY:
1237 			/* This message should be preceeded by GOT_IMSG_TREE. */
1238 			if (*tree == NULL) {
1239 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1240 				break;
1241 			}
1242 			if (datalen < sizeof(*ite) || datalen > MAX_IMSGSIZE) {
1243 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1244 				break;
1245 			}
1246 
1247 			/* Remaining data contains the entry's name. */
1248 			datalen -= sizeof(*ite);
1249 			if (datalen == 0 || datalen > MAX_IMSGSIZE) {
1250 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1251 				break;
1252 			}
1253 			ite = imsg.data;
1254 
1255 			if (datalen + 1 > sizeof(te->name)) {
1256 				err = got_error(GOT_ERR_NO_SPACE);
1257 				break;
1258 			}
1259 			te = &(*tree)->entries[nentries];
1260 			memcpy(te->name, imsg.data + sizeof(*ite), datalen);
1261 			te->name[datalen] = '\0';
1262 
1263 			memcpy(te->id.sha1, ite->id, SHA1_DIGEST_LENGTH);
1264 			te->mode = ite->mode;
1265 			te->idx = nentries;
1266 			nentries++;
1267 			break;
1268 		default:
1269 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1270 			break;
1271 		}
1272 
1273 		imsg_free(&imsg);
1274 	}
1275 done:
1276 	if (*tree && (*tree)->nentries != nentries) {
1277 		if (err == NULL)
1278 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1279 		got_object_tree_close(*tree);
1280 		*tree = NULL;
1281 	}
1282 
1283 	return err;
1284 }
1285 
1286 const struct got_error *
1287 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1288     const uint8_t *data)
1289 {
1290 	struct got_imsg_blob iblob;
1291 
1292 	iblob.size = size;
1293 	iblob.hdrlen = hdrlen;
1294 
1295 	if (data) {
1296 		uint8_t *buf;
1297 
1298 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1299 			return got_error(GOT_ERR_NO_SPACE);
1300 
1301 		buf = malloc(sizeof(iblob) + size);
1302 		if (buf == NULL)
1303 			return got_error_from_errno("malloc");
1304 
1305 		memcpy(buf, &iblob, sizeof(iblob));
1306 		memcpy(buf + sizeof(iblob), data, size);
1307 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1308 		   sizeof(iblob) + size) == -1) {
1309 			free(buf);
1310 			return got_error_from_errno("imsg_compose BLOB");
1311 		}
1312 		free(buf);
1313 	} else {
1314 		/* Data has already been written to file descriptor. */
1315 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1316 		    sizeof(iblob)) == -1)
1317 			return got_error_from_errno("imsg_compose BLOB");
1318 	}
1319 
1320 
1321 	return flush_imsg(ibuf);
1322 }
1323 
1324 const struct got_error *
1325 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1326     struct imsgbuf *ibuf)
1327 {
1328 	const struct got_error *err = NULL;
1329 	struct imsg imsg;
1330 	struct got_imsg_blob *iblob;
1331 	size_t datalen;
1332 
1333 	*outbuf = NULL;
1334 
1335 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1336 	if (err)
1337 		return err;
1338 
1339 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1340 
1341 	switch (imsg.hdr.type) {
1342 	case GOT_IMSG_BLOB:
1343 		if (datalen < sizeof(*iblob)) {
1344 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1345 			break;
1346 		}
1347 		iblob = imsg.data;
1348 		*size = iblob->size;
1349 		*hdrlen = iblob->hdrlen;
1350 
1351 		if (datalen == sizeof(*iblob)) {
1352 			/* Data has been written to file descriptor. */
1353 			break;
1354 		}
1355 
1356 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX) {
1357 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1358 			break;
1359 		}
1360 
1361 		*outbuf = malloc(*size);
1362 		if (*outbuf == NULL) {
1363 			err = got_error_from_errno("malloc");
1364 			break;
1365 		}
1366 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1367 		break;
1368 	default:
1369 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1370 		break;
1371 	}
1372 
1373 	imsg_free(&imsg);
1374 
1375 	return err;
1376 }
1377 
1378 static const struct got_error *
1379 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1380 {
1381 	const struct got_error *err = NULL;
1382 	size_t offset, remain;
1383 
1384 	offset = 0;
1385 	remain = tagmsg_len;
1386 	while (remain > 0) {
1387 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1388 
1389 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1390 		    tag->tagmsg + offset, n) == -1) {
1391 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1392 			break;
1393 		}
1394 
1395 		err = flush_imsg(ibuf);
1396 		if (err)
1397 			break;
1398 
1399 		offset += n;
1400 		remain -= n;
1401 	}
1402 
1403 	return err;
1404 }
1405 
1406 const struct got_error *
1407 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1408 {
1409 	const struct got_error *err = NULL;
1410 	struct got_imsg_tag_object *itag;
1411 	uint8_t *buf;
1412 	size_t len, total;
1413 	size_t tag_len = strlen(tag->tag);
1414 	size_t tagger_len = strlen(tag->tagger);
1415 	size_t tagmsg_len = strlen(tag->tagmsg);
1416 
1417 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1418 
1419 	buf = malloc(total);
1420 	if (buf == NULL)
1421 		return got_error_from_errno("malloc");
1422 
1423 	itag = (struct got_imsg_tag_object *)buf;
1424 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1425 	itag->obj_type = tag->obj_type;
1426 	itag->tag_len = tag_len;
1427 	itag->tagger_len = tagger_len;
1428 	itag->tagger_time = tag->tagger_time;
1429 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1430 	itag->tagmsg_len = tagmsg_len;
1431 
1432 	len = sizeof(*itag);
1433 	memcpy(buf + len, tag->tag, tag_len);
1434 	len += tag_len;
1435 	memcpy(buf + len, tag->tagger, tagger_len);
1436 	len += tagger_len;
1437 
1438 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1439 		err = got_error_from_errno("imsg_compose TAG");
1440 		goto done;
1441 	}
1442 
1443 	if (tagmsg_len == 0 ||
1444 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1445 		err = flush_imsg(ibuf);
1446 		if (err)
1447 			goto done;
1448 	}
1449 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1450 done:
1451 	free(buf);
1452 	return err;
1453 }
1454 
1455 const struct got_error *
1456 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1457 {
1458 	const struct got_error *err = NULL;
1459 	struct imsg imsg;
1460 	struct got_imsg_tag_object *itag;
1461 	size_t len, datalen;
1462 	const size_t min_datalen =
1463 	    MIN(sizeof(struct got_imsg_error),
1464 	    sizeof(struct got_imsg_tag_object));
1465 
1466 	*tag = NULL;
1467 
1468 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1469 	if (err)
1470 		return err;
1471 
1472 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1473 	len = 0;
1474 
1475 	switch (imsg.hdr.type) {
1476 	case GOT_IMSG_TAG:
1477 		if (datalen < sizeof(*itag)) {
1478 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1479 			break;
1480 		}
1481 		itag = imsg.data;
1482 		if (datalen != sizeof(*itag) + itag->tag_len +
1483 		    itag->tagger_len) {
1484 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1485 			break;
1486 		}
1487 		len += sizeof(*itag);
1488 
1489 		*tag = calloc(1, sizeof(**tag));
1490 		if (*tag == NULL) {
1491 			err = got_error_from_errno("calloc");
1492 			break;
1493 		}
1494 
1495 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1496 
1497 		if (itag->tag_len == 0) {
1498 			(*tag)->tag = strdup("");
1499 			if ((*tag)->tag == NULL) {
1500 				err = got_error_from_errno("strdup");
1501 				break;
1502 			}
1503 		} else {
1504 			(*tag)->tag = malloc(itag->tag_len + 1);
1505 			if ((*tag)->tag == NULL) {
1506 				err = got_error_from_errno("malloc");
1507 				break;
1508 			}
1509 			memcpy((*tag)->tag, imsg.data + len,
1510 			    itag->tag_len);
1511 			(*tag)->tag[itag->tag_len] = '\0';
1512 		}
1513 		len += itag->tag_len;
1514 
1515 		(*tag)->obj_type = itag->obj_type;
1516 		(*tag)->tagger_time = itag->tagger_time;
1517 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1518 
1519 		if (itag->tagger_len == 0) {
1520 			(*tag)->tagger = strdup("");
1521 			if ((*tag)->tagger == NULL) {
1522 				err = got_error_from_errno("strdup");
1523 				break;
1524 			}
1525 		} else {
1526 			(*tag)->tagger = malloc(itag->tagger_len + 1);
1527 			if ((*tag)->tagger == NULL) {
1528 				err = got_error_from_errno("malloc");
1529 				break;
1530 			}
1531 			memcpy((*tag)->tagger, imsg.data + len,
1532 			    itag->tagger_len);
1533 			(*tag)->tagger[itag->tagger_len] = '\0';
1534 		}
1535 		len += itag->tagger_len;
1536 
1537 		if (itag->tagmsg_len == 0) {
1538 			(*tag)->tagmsg = strdup("");
1539 			if ((*tag)->tagmsg == NULL) {
1540 				err = got_error_from_errno("strdup");
1541 				break;
1542 			}
1543 		} else {
1544 			size_t offset = 0, remain = itag->tagmsg_len;
1545 
1546 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1547 			if ((*tag)->tagmsg == NULL) {
1548 				err = got_error_from_errno("malloc");
1549 				break;
1550 			}
1551 			while (remain > 0) {
1552 				struct imsg imsg_log;
1553 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1554 				    remain);
1555 
1556 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1557 				if (err)
1558 					return err;
1559 
1560 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1561 					return got_error(GOT_ERR_PRIVSEP_MSG);
1562 
1563 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1564 				    n);
1565 				imsg_free(&imsg_log);
1566 				offset += n;
1567 				remain -= n;
1568 			}
1569 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1570 		}
1571 
1572 		break;
1573 	default:
1574 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1575 		break;
1576 	}
1577 
1578 	imsg_free(&imsg);
1579 
1580 	return err;
1581 }
1582 
1583 const struct got_error *
1584 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1585     struct got_packidx *packidx)
1586 {
1587 	const struct got_error *err = NULL;
1588 	struct got_imsg_packidx ipackidx;
1589 	struct got_imsg_pack ipack;
1590 	int fd;
1591 
1592 	ipackidx.len = packidx->len;
1593 	fd = dup(packidx->fd);
1594 	if (fd == -1)
1595 		return got_error_from_errno("dup");
1596 
1597 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
1598 	    sizeof(ipackidx)) == -1) {
1599 		err = got_error_from_errno("imsg_compose PACKIDX");
1600 		close(fd);
1601 		return err;
1602 	}
1603 
1604 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
1605 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
1606 		return got_error(GOT_ERR_NO_SPACE);
1607 	ipack.filesize = pack->filesize;
1608 
1609 	fd = dup(pack->fd);
1610 	if (fd == -1)
1611 		return got_error_from_errno("dup");
1612 
1613 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
1614 	    == -1) {
1615 		err = got_error_from_errno("imsg_compose PACK");
1616 		close(fd);
1617 		return err;
1618 	}
1619 
1620 	return flush_imsg(ibuf);
1621 }
1622 
1623 const struct got_error *
1624 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
1625     struct got_object_id *id)
1626 {
1627 	struct got_imsg_packed_object iobj;
1628 
1629 	iobj.idx = idx;
1630 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
1631 
1632 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
1633 	    &iobj, sizeof(iobj)) == -1)
1634 		return got_error_from_errno("imsg_compose "
1635 		    "PACKED_OBJECT_REQUEST");
1636 
1637 	return flush_imsg(ibuf);
1638 }
1639 
1640 const struct got_error *
1641 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
1642 {
1643 	const struct got_error *err = NULL;
1644 
1645 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
1646 	    NULL, 0) == -1) {
1647 		err = got_error_from_errno("imsg_compose "
1648 		    "GITCONFIG_PARSE_REQUEST");
1649 		close(fd);
1650 		return err;
1651 	}
1652 
1653 	return flush_imsg(ibuf);
1654 }
1655 
1656 const struct got_error *
1657 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
1658 {
1659 	if (imsg_compose(ibuf,
1660 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
1661 	    NULL, 0) == -1)
1662 		return got_error_from_errno("imsg_compose "
1663 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
1664 
1665 	return flush_imsg(ibuf);
1666 }
1667 
1668 const struct got_error *
1669 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
1670 {
1671 	if (imsg_compose(ibuf,
1672 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
1673 		return got_error_from_errno("imsg_compose "
1674 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
1675 
1676 	return flush_imsg(ibuf);
1677 }
1678 
1679 const struct got_error *
1680 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
1681 {
1682 	if (imsg_compose(ibuf,
1683 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
1684 		return got_error_from_errno("imsg_compose "
1685 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
1686 
1687 	return flush_imsg(ibuf);
1688 }
1689 
1690 const struct got_error *
1691 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
1692 {
1693 	if (imsg_compose(ibuf,
1694 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
1695 		return got_error_from_errno("imsg_compose "
1696 		    "GITCONFIG_REMOTE_REQUEST");
1697 
1698 	return flush_imsg(ibuf);
1699 }
1700 
1701 const struct got_error *
1702 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
1703 {
1704 	if (imsg_compose(ibuf,
1705 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
1706 		return got_error_from_errno("imsg_compose "
1707 		    "GITCONFIG_OWNER_REQUEST");
1708 
1709 	return flush_imsg(ibuf);
1710 }
1711 
1712 const struct got_error *
1713 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
1714 {
1715 	const struct got_error *err = NULL;
1716 	struct imsg imsg;
1717 	size_t datalen;
1718 	const size_t min_datalen = 0;
1719 
1720 	*str = NULL;
1721 
1722 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1723 	if (err)
1724 		return err;
1725 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1726 
1727 	switch (imsg.hdr.type) {
1728 	case GOT_IMSG_GITCONFIG_STR_VAL:
1729 		if (datalen == 0)
1730 			break;
1731 		*str = malloc(datalen);
1732 		if (*str == NULL) {
1733 			err = got_error_from_errno("malloc");
1734 			break;
1735 		}
1736 		if (strlcpy(*str, imsg.data, datalen) >= datalen)
1737 			err = got_error(GOT_ERR_NO_SPACE);
1738 		break;
1739 	default:
1740 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1741 		break;
1742 	}
1743 
1744 	imsg_free(&imsg);
1745 	return err;
1746 }
1747 
1748 const struct got_error *
1749 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
1750 {
1751 	const struct got_error *err = NULL;
1752 	struct imsg imsg;
1753 	size_t datalen;
1754 	const size_t min_datalen =
1755 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
1756 
1757 	*val = 0;
1758 
1759 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1760 	if (err)
1761 		return err;
1762 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1763 
1764 	switch (imsg.hdr.type) {
1765 	case GOT_IMSG_GITCONFIG_INT_VAL:
1766 		if (datalen != sizeof(*val)) {
1767 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1768 			break;
1769 		}
1770 		memcpy(val, imsg.data, sizeof(*val));
1771 		break;
1772 	default:
1773 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1774 		break;
1775 	}
1776 
1777 	imsg_free(&imsg);
1778 	return err;
1779 }
1780 
1781 const struct got_error *
1782 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
1783     int *nremotes, struct imsgbuf *ibuf)
1784 {
1785 	const struct got_error *err = NULL;
1786 	struct imsg imsg;
1787 	size_t datalen;
1788 	struct got_imsg_remotes iremotes;
1789 	struct got_imsg_remote iremote;
1790 
1791 	*remotes = NULL;
1792 	*nremotes = 0;
1793 	iremotes.nremotes = 0;
1794 
1795 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
1796 	if (err)
1797 		return err;
1798 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1799 
1800 	switch (imsg.hdr.type) {
1801 	case GOT_IMSG_GITCONFIG_REMOTES:
1802 		if (datalen != sizeof(iremotes)) {
1803 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1804 			break;
1805 		}
1806 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
1807 		if (iremotes.nremotes == 0) {
1808 			imsg_free(&imsg);
1809 			return NULL;
1810 		}
1811 		break;
1812 	default:
1813 		imsg_free(&imsg);
1814 		return got_error(GOT_ERR_PRIVSEP_MSG);
1815 	}
1816 
1817 	imsg_free(&imsg);
1818 
1819 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
1820 	if (*remotes == NULL)
1821 		return got_error_from_errno("recallocarray");
1822 
1823 	while (*nremotes < iremotes.nremotes) {
1824 		struct got_remote_repo *remote;
1825 	
1826 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
1827 		if (err)
1828 			break;
1829 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1830 
1831 		switch (imsg.hdr.type) {
1832 		case GOT_IMSG_GITCONFIG_REMOTE:
1833 			remote = &(*remotes)[*nremotes];
1834 			if (datalen < sizeof(iremote)) {
1835 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1836 				break;
1837 			}
1838 			memcpy(&iremote, imsg.data, sizeof(iremote));
1839 			if (iremote.name_len == 0 || iremote.url_len == 0 ||
1840 			    (sizeof(iremote) + iremote.name_len +
1841 			    iremote.url_len) > datalen) {
1842 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1843 				break;
1844 			}
1845 			remote->name = strndup(imsg.data + sizeof(iremote),
1846 			    iremote.name_len);
1847 			if (remote->name == NULL) {
1848 				err = got_error_from_errno("strndup");
1849 				break;
1850 			}
1851 			remote->url = strndup(imsg.data + sizeof(iremote) +
1852 			    iremote.name_len, iremote.url_len);
1853 			if (remote->url == NULL) {
1854 				err = got_error_from_errno("strndup");
1855 				free(remote->name);
1856 				break;
1857 			}
1858 			remote->mirror_references = iremote.mirror_references;
1859 			(*nremotes)++;
1860 			break;
1861 		default:
1862 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1863 			break;
1864 		}
1865 
1866 		imsg_free(&imsg);
1867 		if (err)
1868 			break;
1869 	}
1870 
1871 	if (err) {
1872 		int i;
1873 		for (i = 0; i < *nremotes; i++) {
1874 			free((*remotes)[i].name);
1875 			free((*remotes)[i].url);
1876 		}
1877 		free(*remotes);
1878 		*remotes = NULL;
1879 		*nremotes = 0;
1880 	}
1881 	return err;
1882 }
1883 
1884 const struct got_error *
1885 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
1886      struct got_object_id *id, int idx, const char *path)
1887 {
1888 	const struct got_error *err = NULL;
1889 	struct ibuf *wbuf;
1890 	size_t path_len = strlen(path) + 1;
1891 
1892 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
1893 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
1894 	if (wbuf == NULL)
1895 		return got_error_from_errno(
1896 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
1897 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
1898 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
1899 		ibuf_free(wbuf);
1900 		return err;
1901 	}
1902 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1) {
1903 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
1904 		ibuf_free(wbuf);
1905 		return err;
1906 	}
1907 	if (imsg_add(wbuf, path, path_len) == -1) {
1908 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
1909 		ibuf_free(wbuf);
1910 		return err;
1911 	}
1912 
1913 	wbuf->fd = -1;
1914 	imsg_close(ibuf, wbuf);
1915 
1916 	return flush_imsg(ibuf);
1917 }
1918 
1919 const struct got_error *
1920 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
1921     struct got_object_id **changed_commit_id,
1922     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
1923 {
1924 	const struct got_error *err = NULL;
1925 	struct imsg imsg;
1926 	struct got_imsg_traversed_commits *icommits;
1927 	size_t datalen;
1928 	int i, done = 0;
1929 
1930 	*changed_commit = NULL;
1931 	*changed_commit_id = NULL;
1932 
1933 	while (!done) {
1934 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1935 		if (err)
1936 			return err;
1937 
1938 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1939 		switch (imsg.hdr.type) {
1940 		case GOT_IMSG_TRAVERSED_COMMITS:
1941 			icommits = imsg.data;
1942 			if (datalen != sizeof(*icommits) +
1943 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
1944 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1945 				break;
1946 			}
1947 			for (i = 0; i < icommits->ncommits; i++) {
1948 				struct got_object_qid *qid;
1949 				uint8_t *sha1 = (uint8_t *)imsg.data +
1950 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
1951 				err = got_object_qid_alloc_partial(&qid);
1952 				if (err)
1953 					break;
1954 				memcpy(qid->id->sha1, sha1, SHA1_DIGEST_LENGTH);
1955 				SIMPLEQ_INSERT_TAIL(commit_ids, qid, entry);
1956 
1957 				/* The last commit may contain a change. */
1958 				if (i == icommits->ncommits - 1) {
1959 					*changed_commit_id =
1960 					    got_object_id_dup(qid->id);
1961 					if (*changed_commit_id == NULL) {
1962 						err = got_error_from_errno(
1963 						    "got_object_id_dup");
1964 						break;
1965 					}
1966 				}
1967 			}
1968 			break;
1969 		case GOT_IMSG_COMMIT:
1970 			if (*changed_commit_id == NULL) {
1971 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1972 				break;
1973 			}
1974 			err = get_commit_from_imsg(changed_commit, &imsg,
1975 			    datalen, ibuf);
1976 			break;
1977 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
1978 			done = 1;
1979 			break;
1980 		default:
1981 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1982 			break;
1983 		}
1984 
1985 		imsg_free(&imsg);
1986 		if (err)
1987 			break;
1988 	}
1989 
1990 	if (err)
1991 		got_object_id_queue_free(commit_ids);
1992 	return err;
1993 }
1994 
1995 const struct got_error *
1996 got_privsep_unveil_exec_helpers(void)
1997 {
1998 	const char *helpers[] = {
1999 	    GOT_PATH_PROG_READ_PACK,
2000 	    GOT_PATH_PROG_READ_OBJECT,
2001 	    GOT_PATH_PROG_READ_COMMIT,
2002 	    GOT_PATH_PROG_READ_TREE,
2003 	    GOT_PATH_PROG_READ_BLOB,
2004 	    GOT_PATH_PROG_READ_TAG,
2005 	    GOT_PATH_PROG_READ_GITCONFIG,
2006 	    GOT_PATH_PROG_FETCH_PACK,
2007 	    GOT_PATH_PROG_INDEX_PACK,
2008 	};
2009 	int i;
2010 
2011 	for (i = 0; i < nitems(helpers); i++) {
2012 		if (unveil(helpers[i], "x") == 0)
2013 			continue;
2014 		return got_error_from_errno2("unveil", helpers[i]);
2015 	}
2016 
2017 	return NULL;
2018 }
2019 
2020 void
2021 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
2022 {
2023 	if (close(imsg_fds[0]) != 0) {
2024 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2025 		_exit(1);
2026 	}
2027 
2028 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
2029 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2030 		_exit(1);
2031 	}
2032 	if (closefrom(GOT_IMSG_FD_CHILD + 1) == -1) {
2033 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2034 		_exit(1);
2035 	}
2036 
2037 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
2038 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
2039 		    strerror(errno));
2040 		_exit(1);
2041 	}
2042 }