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Date:: Sun Mar 22 17:20:18 2020 UTC
Message:: move functions from privsep.c to the helpers which use them where possible
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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, 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 
587 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
588 	if (err)
589 		return err;
590 
591 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
592 	switch (imsg.hdr.type) {
593 	case GOT_IMSG_ERROR:
594 		if (datalen < sizeof(struct got_imsg_error)) {
595 			err = got_error(GOT_ERR_PRIVSEP_LEN);
596 			break;
597 		}
598 		err = recv_imsg_error(&imsg, datalen);
599 		break;
600 	case GOT_IMSG_FETCH_SYMREFS:
601 		if (datalen < sizeof(*isymrefs)) {
602 			err = got_error(GOT_ERR_PRIVSEP_LEN);
603 			break;
604 		}
605 		if (isymrefs != NULL) {
606 			err = got_error(GOT_ERR_PRIVSEP_MSG);
607 			break;
608 		}
609 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
610 		off = sizeof(*isymrefs);
611 		remain = datalen - off;
612 		for (n = 0; n < isymrefs->nsymrefs; n++) {
613 			struct got_imsg_fetch_symref *s;
614 			char *name, *target;
615 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
616 				err = got_error(GOT_ERR_PRIVSEP_LEN);
617 				goto done;
618 			}
619 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
620 			off += sizeof(*s);
621 			remain -= sizeof(*s);
622 			if (remain < s->name_len) {
623 				err = got_error(GOT_ERR_PRIVSEP_LEN);
624 				goto done;
625 			}
626 			name = strndup(imsg.data + off, s->name_len);
627 			if (name == NULL) {
628 				err = got_error_from_errno("strndup");
629 				goto done;
630 			}
631 			off += s->name_len;
632 			remain -= s->name_len;
633 			if (remain < s->target_len) {
634 				err = got_error(GOT_ERR_PRIVSEP_LEN);
635 				free(name);
636 				goto done;
637 			}
638 			target = strndup(imsg.data + off, s->target_len);
639 			if (target == NULL) {
640 				err = got_error_from_errno("strndup");
641 				free(name);
642 				goto done;
643 			}
644 			off += s->target_len;
645 			remain -= s->target_len;
646 			err = got_pathlist_append(symrefs, name, target);
647 			if (err) {
648 				free(name);
649 				free(target);
650 				goto done;
651 			}
652 		}
653 		break;
654 	case GOT_IMSG_FETCH_REF:
655 		if (datalen <= SHA1_DIGEST_LENGTH) {
656 			err = got_error(GOT_ERR_PRIVSEP_MSG);
657 			break;
658 		}
659 		*id = malloc(sizeof(**id));
660 		if (*id == NULL) {
661 			err = got_error_from_errno("malloc");
662 			break;
663 		}
664 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
665 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
666 		    datalen - SHA1_DIGEST_LENGTH);
667 		if (*refname == NULL) {
668 			err = got_error_from_errno("strndup");
669 			break;
670 		}
671 		break;
672 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
673 		if (datalen == 0) {
674 			err = got_error(GOT_ERR_PRIVSEP_LEN);
675 			break;
676 		}
677 		*server_progress = strndup(imsg.data, datalen);
678 		if (*server_progress == NULL) {
679 			err = got_error_from_errno("strndup");
680 			break;
681 		}
682 		for (i = 0; i < datalen; i++) {
683 			if (!isprint((unsigned char)(*server_progress)[i]) &&
684 			    !isspace((unsigned char)(*server_progress)[i])) {
685 				err = got_error(GOT_ERR_PRIVSEP_MSG);
686 				free(*server_progress);
687 				*server_progress = NULL;
688 				goto done;
689 			}
690 		}
691 		break;
692 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
693 		if (datalen < sizeof(*packfile_size)) {
694 			err = got_error(GOT_ERR_PRIVSEP_MSG);
695 			break;
696 		}
697 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
698 		break;
699 	case GOT_IMSG_FETCH_DONE:
700 		*id = malloc(sizeof(**id));
701 		if (*id == NULL) {
702 			err = got_error_from_errno("malloc");
703 			break;
704 		}
705 		if (datalen != SHA1_DIGEST_LENGTH) {
706 			err = got_error(GOT_ERR_PRIVSEP_MSG);
707 			break;
708 		}
709 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
710 		*done = 1;
711 		break;
712 	default:
713 		err = got_error(GOT_ERR_PRIVSEP_MSG);
714 		break;
715 	}
716 done:
717 	if (err) {
718 		free(*id);
719 		*id = NULL;
720 		free(*refname);
721 		*refname = NULL;
722 	}
723 	imsg_free(&imsg);
724 	return err;
725 }
726 
727 const struct got_error *
728 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_hash,
729     int fd)
730 {
731 	const struct got_error *err = NULL;
732 
733 	/* Keep in sync with struct got_imsg_index_pack_request */
734 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
735 	    pack_hash, SHA1_DIGEST_LENGTH) == -1) {
736 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
737 		close(fd);
738 		return err;
739 	}
740 	return flush_imsg(ibuf);
741 }
742 
743 const struct got_error *
744 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
745 {
746 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
747 }
748 
749 const struct got_error *
750 got_privsep_recv_index_progress(int *done, int *nobj_total,
751     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
752     struct imsgbuf *ibuf)
753 {
754 	const struct got_error *err = NULL;
755 	struct imsg imsg;
756 	struct got_imsg_index_pack_progress *iprogress;
757 	size_t datalen;
758 
759 	*done = 0;
760 	*nobj_total = 0;
761 	*nobj_indexed = 0;
762 	*nobj_resolved = 0;
763 
764 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
765 	if (err)
766 		return err;
767 
768 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
769 	switch (imsg.hdr.type) {
770 	case GOT_IMSG_ERROR:
771 		if (datalen < sizeof(struct got_imsg_error)) {
772 			err = got_error(GOT_ERR_PRIVSEP_LEN);
773 			break;
774 		}
775 		err = recv_imsg_error(&imsg, datalen);
776 		break;
777 	case GOT_IMSG_IDXPACK_PROGRESS:
778 		if (datalen < sizeof(*iprogress)) {
779 			err = got_error(GOT_ERR_PRIVSEP_LEN);
780 			break;
781 		}
782 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
783 		*nobj_total = iprogress->nobj_total;
784 		*nobj_indexed = iprogress->nobj_indexed;
785 		*nobj_loose = iprogress->nobj_loose;
786 		*nobj_resolved = iprogress->nobj_resolved;
787 		break;
788 	case GOT_IMSG_IDXPACK_DONE:
789 		if (datalen != 0) {
790 			err = got_error(GOT_ERR_PRIVSEP_LEN);
791 			break;
792 		}
793 		*done = 1;
794 		break;
795 	default:
796 		err = got_error(GOT_ERR_PRIVSEP_MSG);
797 		break;
798 	}
799 
800 	imsg_free(&imsg);
801 	return err;
802 }
803 
804 const struct got_error *
805 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
806     struct imsgbuf *ibuf)
807 {
808 	const struct got_error *err = NULL;
809 	struct got_imsg_object *iobj;
810 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
811 
812 	if (datalen != sizeof(*iobj))
813 		return got_error(GOT_ERR_PRIVSEP_LEN);
814 	iobj = imsg->data;
815 
816 	*obj = calloc(1, sizeof(**obj));
817 	if (*obj == NULL)
818 		return got_error_from_errno("calloc");
819 
820 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
821 	(*obj)->type = iobj->type;
822 	(*obj)->flags = iobj->flags;
823 	(*obj)->hdrlen = iobj->hdrlen;
824 	(*obj)->size = iobj->size;
825 	/* path_packfile is handled by caller */
826 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
827 		(*obj)->pack_offset = iobj->pack_offset;
828 		(*obj)->pack_idx = iobj->pack_idx;
829 	}
830 
831 	return err;
832 }
833 
834 const struct got_error *
835 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
836 {
837 	const struct got_error *err = NULL;
838 	struct imsg imsg;
839 	const size_t min_datalen =
840 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
841 
842 	*obj = NULL;
843 
844 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
845 	if (err)
846 		return err;
847 
848 	switch (imsg.hdr.type) {
849 	case GOT_IMSG_OBJECT:
850 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
851 		break;
852 	default:
853 		err = got_error(GOT_ERR_PRIVSEP_MSG);
854 		break;
855 	}
856 
857 	imsg_free(&imsg);
858 
859 	return err;
860 }
861 
862 static const struct got_error *
863 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
864     size_t logmsg_len)
865 {
866 	const struct got_error *err = NULL;
867 	size_t offset, remain;
868 
869 	offset = 0;
870 	remain = logmsg_len;
871 	while (remain > 0) {
872 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
873 
874 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
875 		    commit->logmsg + offset, n) == -1) {
876 			err = got_error_from_errno("imsg_compose "
877 			    "COMMIT_LOGMSG");
878 			break;
879 		}
880 
881 		err = flush_imsg(ibuf);
882 		if (err)
883 			break;
884 
885 		offset += n;
886 		remain -= n;
887 	}
888 
889 	return err;
890 }
891 
892 const struct got_error *
893 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
894 {
895 	const struct got_error *err = NULL;
896 	struct got_imsg_commit_object *icommit;
897 	uint8_t *buf;
898 	size_t len, total;
899 	struct got_object_qid *qid;
900 	size_t author_len = strlen(commit->author);
901 	size_t committer_len = strlen(commit->committer);
902 	size_t logmsg_len = strlen(commit->logmsg);
903 
904 	total = sizeof(*icommit) + author_len + committer_len +
905 	    commit->nparents * SHA1_DIGEST_LENGTH;
906 
907 	buf = malloc(total);
908 	if (buf == NULL)
909 		return got_error_from_errno("malloc");
910 
911 	icommit = (struct got_imsg_commit_object *)buf;
912 	memcpy(icommit->tree_id, commit->tree_id->sha1,
913 	    sizeof(icommit->tree_id));
914 	icommit->author_len = author_len;
915 	icommit->author_time = commit->author_time;
916 	icommit->author_gmtoff = commit->author_gmtoff;
917 	icommit->committer_len = committer_len;
918 	icommit->committer_time = commit->committer_time;
919 	icommit->committer_gmtoff = commit->committer_gmtoff;
920 	icommit->logmsg_len = logmsg_len;
921 	icommit->nparents = commit->nparents;
922 
923 	len = sizeof(*icommit);
924 	memcpy(buf + len, commit->author, author_len);
925 	len += author_len;
926 	memcpy(buf + len, commit->committer, committer_len);
927 	len += committer_len;
928 	SIMPLEQ_FOREACH(qid, &commit->parent_ids, entry) {
929 		memcpy(buf + len, qid->id, SHA1_DIGEST_LENGTH);
930 		len += SHA1_DIGEST_LENGTH;
931 	}
932 
933 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
934 		err = got_error_from_errno("imsg_compose COMMIT");
935 		goto done;
936 	}
937 
938 	if (logmsg_len == 0 ||
939 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
940 		err = flush_imsg(ibuf);
941 		if (err)
942 			goto done;
943 	}
944 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
945 done:
946 	free(buf);
947 	return err;
948 }
949 
950 static const struct got_error *
951 get_commit_from_imsg(struct got_commit_object **commit,
952     struct imsg *imsg, size_t datalen, struct imsgbuf *ibuf)
953 {
954 	const struct got_error *err = NULL;
955 	struct got_imsg_commit_object *icommit;
956 	size_t len = 0;
957 	int i;
958 
959 	if (datalen < sizeof(*icommit))
960 		return got_error(GOT_ERR_PRIVSEP_LEN);
961 
962 	icommit = imsg->data;
963 	if (datalen != sizeof(*icommit) + icommit->author_len +
964 	    icommit->committer_len +
965 	    icommit->nparents * SHA1_DIGEST_LENGTH)
966 		return got_error(GOT_ERR_PRIVSEP_LEN);
967 
968 	if (icommit->nparents < 0)
969 		return got_error(GOT_ERR_PRIVSEP_LEN);
970 
971 	len += sizeof(*icommit);
972 
973 	*commit = got_object_commit_alloc_partial();
974 	if (*commit == NULL)
975 		return got_error_from_errno(
976 		    "got_object_commit_alloc_partial");
977 
978 	memcpy((*commit)->tree_id->sha1, icommit->tree_id,
979 	    SHA1_DIGEST_LENGTH);
980 	(*commit)->author_time = icommit->author_time;
981 	(*commit)->author_gmtoff = icommit->author_gmtoff;
982 	(*commit)->committer_time = icommit->committer_time;
983 	(*commit)->committer_gmtoff = icommit->committer_gmtoff;
984 
985 	if (icommit->author_len == 0) {
986 		(*commit)->author = strdup("");
987 		if ((*commit)->author == NULL) {
988 			err = got_error_from_errno("strdup");
989 			goto done;
990 		}
991 	} else {
992 		(*commit)->author = malloc(icommit->author_len + 1);
993 		if ((*commit)->author == NULL) {
994 			err = got_error_from_errno("malloc");
995 			goto done;
996 		}
997 		memcpy((*commit)->author, imsg->data + len,
998 		    icommit->author_len);
999 		(*commit)->author[icommit->author_len] = '\0';
1000 	}
1001 	len += icommit->author_len;
1002 
1003 	if (icommit->committer_len == 0) {
1004 		(*commit)->committer = strdup("");
1005 		if ((*commit)->committer == NULL) {
1006 			err = got_error_from_errno("strdup");
1007 			goto done;
1008 		}
1009 	} else {
1010 		(*commit)->committer =
1011 		    malloc(icommit->committer_len + 1);
1012 		if ((*commit)->committer == NULL) {
1013 			err = got_error_from_errno("malloc");
1014 			goto done;
1015 		}
1016 		memcpy((*commit)->committer, imsg->data + len,
1017 		    icommit->committer_len);
1018 		(*commit)->committer[icommit->committer_len] = '\0';
1019 	}
1020 	len += icommit->committer_len;
1021 
1022 	if (icommit->logmsg_len == 0) {
1023 		(*commit)->logmsg = strdup("");
1024 		if ((*commit)->logmsg == NULL) {
1025 			err = got_error_from_errno("strdup");
1026 			goto done;
1027 		}
1028 	} else {
1029 		size_t offset = 0, remain = icommit->logmsg_len;
1030 
1031 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1032 		if ((*commit)->logmsg == NULL) {
1033 			err = got_error_from_errno("malloc");
1034 			goto done;
1035 		}
1036 		while (remain > 0) {
1037 			struct imsg imsg_log;
1038 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1039 			    remain);
1040 
1041 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1042 			if (err)
1043 				goto done;
1044 
1045 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1046 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1047 				goto done;
1048 			}
1049 
1050 			memcpy((*commit)->logmsg + offset,
1051 			    imsg_log.data, n);
1052 			imsg_free(&imsg_log);
1053 			offset += n;
1054 			remain -= n;
1055 		}
1056 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1057 	}
1058 
1059 	for (i = 0; i < icommit->nparents; i++) {
1060 		struct got_object_qid *qid;
1061 
1062 		err = got_object_qid_alloc_partial(&qid);
1063 		if (err)
1064 			break;
1065 		memcpy(qid->id, imsg->data + len +
1066 		    i * SHA1_DIGEST_LENGTH, sizeof(*qid->id));
1067 		SIMPLEQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1068 		(*commit)->nparents++;
1069 	}
1070 done:
1071 	if (err) {
1072 		got_object_commit_close(*commit);
1073 		*commit = NULL;
1074 	}
1075 	return err;
1076 }
1077 
1078 const struct got_error *
1079 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1080 {
1081 	const struct got_error *err = NULL;
1082 	struct imsg imsg;
1083 	size_t datalen;
1084 	const size_t min_datalen =
1085 	    MIN(sizeof(struct got_imsg_error),
1086 	    sizeof(struct got_imsg_commit_object));
1087 
1088 	*commit = NULL;
1089 
1090 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1091 	if (err)
1092 		return err;
1093 
1094 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1095 
1096 	switch (imsg.hdr.type) {
1097 	case GOT_IMSG_COMMIT:
1098 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1099 		break;
1100 	default:
1101 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1102 		break;
1103 	}
1104 
1105 	imsg_free(&imsg);
1106 
1107 	return err;
1108 }
1109 
1110 const struct got_error *
1111 got_privsep_send_tree(struct imsgbuf *ibuf, struct got_pathlist_head *entries,
1112     int nentries)
1113 {
1114 	const struct got_error *err = NULL;
1115 	struct got_imsg_tree_object itree;
1116 	struct got_pathlist_entry *pe;
1117 	size_t totlen;
1118 	int nimsg; /* number of imsg queued in ibuf */
1119 
1120 	itree.nentries = nentries;
1121 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1122 	    == -1)
1123 		return got_error_from_errno("imsg_compose TREE");
1124 
1125 	totlen = sizeof(itree);
1126 	nimsg = 1;
1127 	TAILQ_FOREACH(pe, entries, entry) {
1128 		const char *name = pe->path;
1129 		struct got_parsed_tree_entry *pte = pe->data;
1130 		struct ibuf *wbuf;
1131 		size_t namelen = strlen(name);
1132 		size_t len = sizeof(struct got_imsg_tree_entry) + namelen;
1133 
1134 		if (len > MAX_IMSGSIZE)
1135 			return got_error(GOT_ERR_NO_SPACE);
1136 
1137 		nimsg++;
1138 		if (totlen + len >= MAX_IMSGSIZE - (IMSG_HEADER_SIZE * nimsg)) {
1139 			err = flush_imsg(ibuf);
1140 			if (err)
1141 				return err;
1142 			nimsg = 0;
1143 		}
1144 
1145 		wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRY, 0, 0, len);
1146 		if (wbuf == NULL)
1147 			return got_error_from_errno("imsg_create TREE_ENTRY");
1148 
1149 		/* Keep in sync with struct got_imsg_tree_object definition! */
1150 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1) {
1151 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1152 			ibuf_free(wbuf);
1153 			return err;
1154 		}
1155 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1) {
1156 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1157 			ibuf_free(wbuf);
1158 			return err;
1159 		}
1160 
1161 		if (imsg_add(wbuf, name, namelen) == -1) {
1162 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1163 			ibuf_free(wbuf);
1164 			return err;
1165 		}
1166 
1167 		wbuf->fd = -1;
1168 		imsg_close(ibuf, wbuf);
1169 
1170 		totlen += len;
1171 	}
1172 
1173 	return flush_imsg(ibuf);
1174 }
1175 
1176 const struct got_error *
1177 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1178 {
1179 	const struct got_error *err = NULL;
1180 	const size_t min_datalen =
1181 	    MIN(sizeof(struct got_imsg_error),
1182 	    sizeof(struct got_imsg_tree_object));
1183 	struct got_imsg_tree_object *itree;
1184 	int nentries = 0;
1185 
1186 	*tree = NULL;
1187 get_more:
1188 	err = read_imsg(ibuf);
1189 	if (err)
1190 		goto done;
1191 
1192 	for (;;) {
1193 		struct imsg imsg;
1194 		size_t n;
1195 		size_t datalen;
1196 		struct got_imsg_tree_entry *ite;
1197 		struct got_tree_entry *te = NULL;
1198 
1199 		n = imsg_get(ibuf, &imsg);
1200 		if (n == 0) {
1201 			if (*tree && (*tree)->nentries != nentries)
1202 				goto get_more;
1203 			break;
1204 		}
1205 
1206 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen)
1207 			return got_error(GOT_ERR_PRIVSEP_LEN);
1208 
1209 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1210 
1211 		switch (imsg.hdr.type) {
1212 		case GOT_IMSG_ERROR:
1213 			err = recv_imsg_error(&imsg, datalen);
1214 			break;
1215 		case GOT_IMSG_TREE:
1216 			/* This message should only appear once. */
1217 			if (*tree != NULL) {
1218 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1219 				break;
1220 			}
1221 			if (datalen != sizeof(*itree)) {
1222 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1223 				break;
1224 			}
1225 			itree = imsg.data;
1226 			*tree = malloc(sizeof(**tree));
1227 			if (*tree == NULL) {
1228 				err = got_error_from_errno("malloc");
1229 				break;
1230 			}
1231 			(*tree)->entries = calloc(itree->nentries,
1232 			    sizeof(struct got_tree_entry));
1233 			if ((*tree)->entries == NULL) {
1234 				err = got_error_from_errno("malloc");
1235 				break;
1236 			}
1237 			(*tree)->nentries = itree->nentries;
1238 			(*tree)->refcnt = 0;
1239 			break;
1240 		case GOT_IMSG_TREE_ENTRY:
1241 			/* This message should be preceeded by GOT_IMSG_TREE. */
1242 			if (*tree == NULL) {
1243 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1244 				break;
1245 			}
1246 			if (datalen < sizeof(*ite) || datalen > MAX_IMSGSIZE) {
1247 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1248 				break;
1249 			}
1250 
1251 			/* Remaining data contains the entry's name. */
1252 			datalen -= sizeof(*ite);
1253 			if (datalen == 0 || datalen > MAX_IMSGSIZE) {
1254 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1255 				break;
1256 			}
1257 			ite = imsg.data;
1258 
1259 			if (datalen + 1 > sizeof(te->name)) {
1260 				err = got_error(GOT_ERR_NO_SPACE);
1261 				break;
1262 			}
1263 			te = &(*tree)->entries[nentries];
1264 			memcpy(te->name, imsg.data + sizeof(*ite), datalen);
1265 			te->name[datalen] = '\0';
1266 
1267 			memcpy(te->id.sha1, ite->id, SHA1_DIGEST_LENGTH);
1268 			te->mode = ite->mode;
1269 			te->idx = nentries;
1270 			nentries++;
1271 			break;
1272 		default:
1273 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1274 			break;
1275 		}
1276 
1277 		imsg_free(&imsg);
1278 	}
1279 done:
1280 	if (*tree && (*tree)->nentries != nentries) {
1281 		if (err == NULL)
1282 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1283 		got_object_tree_close(*tree);
1284 		*tree = NULL;
1285 	}
1286 
1287 	return err;
1288 }
1289 
1290 const struct got_error *
1291 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1292     const uint8_t *data)
1293 {
1294 	struct got_imsg_blob iblob;
1295 
1296 	iblob.size = size;
1297 	iblob.hdrlen = hdrlen;
1298 
1299 	if (data) {
1300 		uint8_t *buf;
1301 
1302 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1303 			return got_error(GOT_ERR_NO_SPACE);
1304 
1305 		buf = malloc(sizeof(iblob) + size);
1306 		if (buf == NULL)
1307 			return got_error_from_errno("malloc");
1308 
1309 		memcpy(buf, &iblob, sizeof(iblob));
1310 		memcpy(buf + sizeof(iblob), data, size);
1311 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1312 		   sizeof(iblob) + size) == -1) {
1313 			free(buf);
1314 			return got_error_from_errno("imsg_compose BLOB");
1315 		}
1316 		free(buf);
1317 	} else {
1318 		/* Data has already been written to file descriptor. */
1319 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1320 		    sizeof(iblob)) == -1)
1321 			return got_error_from_errno("imsg_compose BLOB");
1322 	}
1323 
1324 
1325 	return flush_imsg(ibuf);
1326 }
1327 
1328 const struct got_error *
1329 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1330     struct imsgbuf *ibuf)
1331 {
1332 	const struct got_error *err = NULL;
1333 	struct imsg imsg;
1334 	struct got_imsg_blob *iblob;
1335 	size_t datalen;
1336 
1337 	*outbuf = NULL;
1338 
1339 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1340 	if (err)
1341 		return err;
1342 
1343 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1344 
1345 	switch (imsg.hdr.type) {
1346 	case GOT_IMSG_BLOB:
1347 		if (datalen < sizeof(*iblob)) {
1348 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1349 			break;
1350 		}
1351 		iblob = imsg.data;
1352 		*size = iblob->size;
1353 		*hdrlen = iblob->hdrlen;
1354 
1355 		if (datalen == sizeof(*iblob)) {
1356 			/* Data has been written to file descriptor. */
1357 			break;
1358 		}
1359 
1360 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX) {
1361 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1362 			break;
1363 		}
1364 
1365 		*outbuf = malloc(*size);
1366 		if (*outbuf == NULL) {
1367 			err = got_error_from_errno("malloc");
1368 			break;
1369 		}
1370 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1371 		break;
1372 	default:
1373 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1374 		break;
1375 	}
1376 
1377 	imsg_free(&imsg);
1378 
1379 	return err;
1380 }
1381 
1382 static const struct got_error *
1383 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1384 {
1385 	const struct got_error *err = NULL;
1386 	size_t offset, remain;
1387 
1388 	offset = 0;
1389 	remain = tagmsg_len;
1390 	while (remain > 0) {
1391 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1392 
1393 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1394 		    tag->tagmsg + offset, n) == -1) {
1395 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1396 			break;
1397 		}
1398 
1399 		err = flush_imsg(ibuf);
1400 		if (err)
1401 			break;
1402 
1403 		offset += n;
1404 		remain -= n;
1405 	}
1406 
1407 	return err;
1408 }
1409 
1410 const struct got_error *
1411 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1412 {
1413 	const struct got_error *err = NULL;
1414 	struct got_imsg_tag_object *itag;
1415 	uint8_t *buf;
1416 	size_t len, total;
1417 	size_t tag_len = strlen(tag->tag);
1418 	size_t tagger_len = strlen(tag->tagger);
1419 	size_t tagmsg_len = strlen(tag->tagmsg);
1420 
1421 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1422 
1423 	buf = malloc(total);
1424 	if (buf == NULL)
1425 		return got_error_from_errno("malloc");
1426 
1427 	itag = (struct got_imsg_tag_object *)buf;
1428 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1429 	itag->obj_type = tag->obj_type;
1430 	itag->tag_len = tag_len;
1431 	itag->tagger_len = tagger_len;
1432 	itag->tagger_time = tag->tagger_time;
1433 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1434 	itag->tagmsg_len = tagmsg_len;
1435 
1436 	len = sizeof(*itag);
1437 	memcpy(buf + len, tag->tag, tag_len);
1438 	len += tag_len;
1439 	memcpy(buf + len, tag->tagger, tagger_len);
1440 	len += tagger_len;
1441 
1442 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1443 		err = got_error_from_errno("imsg_compose TAG");
1444 		goto done;
1445 	}
1446 
1447 	if (tagmsg_len == 0 ||
1448 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1449 		err = flush_imsg(ibuf);
1450 		if (err)
1451 			goto done;
1452 	}
1453 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1454 done:
1455 	free(buf);
1456 	return err;
1457 }
1458 
1459 const struct got_error *
1460 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1461 {
1462 	const struct got_error *err = NULL;
1463 	struct imsg imsg;
1464 	struct got_imsg_tag_object *itag;
1465 	size_t len, datalen;
1466 	const size_t min_datalen =
1467 	    MIN(sizeof(struct got_imsg_error),
1468 	    sizeof(struct got_imsg_tag_object));
1469 
1470 	*tag = NULL;
1471 
1472 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1473 	if (err)
1474 		return err;
1475 
1476 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1477 	len = 0;
1478 
1479 	switch (imsg.hdr.type) {
1480 	case GOT_IMSG_TAG:
1481 		if (datalen < sizeof(*itag)) {
1482 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1483 			break;
1484 		}
1485 		itag = imsg.data;
1486 		if (datalen != sizeof(*itag) + itag->tag_len +
1487 		    itag->tagger_len) {
1488 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1489 			break;
1490 		}
1491 		len += sizeof(*itag);
1492 
1493 		*tag = calloc(1, sizeof(**tag));
1494 		if (*tag == NULL) {
1495 			err = got_error_from_errno("calloc");
1496 			break;
1497 		}
1498 
1499 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1500 
1501 		if (itag->tag_len == 0) {
1502 			(*tag)->tag = strdup("");
1503 			if ((*tag)->tag == NULL) {
1504 				err = got_error_from_errno("strdup");
1505 				break;
1506 			}
1507 		} else {
1508 			(*tag)->tag = malloc(itag->tag_len + 1);
1509 			if ((*tag)->tag == NULL) {
1510 				err = got_error_from_errno("malloc");
1511 				break;
1512 			}
1513 			memcpy((*tag)->tag, imsg.data + len,
1514 			    itag->tag_len);
1515 			(*tag)->tag[itag->tag_len] = '\0';
1516 		}
1517 		len += itag->tag_len;
1518 
1519 		(*tag)->obj_type = itag->obj_type;
1520 		(*tag)->tagger_time = itag->tagger_time;
1521 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1522 
1523 		if (itag->tagger_len == 0) {
1524 			(*tag)->tagger = strdup("");
1525 			if ((*tag)->tagger == NULL) {
1526 				err = got_error_from_errno("strdup");
1527 				break;
1528 			}
1529 		} else {
1530 			(*tag)->tagger = malloc(itag->tagger_len + 1);
1531 			if ((*tag)->tagger == NULL) {
1532 				err = got_error_from_errno("malloc");
1533 				break;
1534 			}
1535 			memcpy((*tag)->tagger, imsg.data + len,
1536 			    itag->tagger_len);
1537 			(*tag)->tagger[itag->tagger_len] = '\0';
1538 		}
1539 		len += itag->tagger_len;
1540 
1541 		if (itag->tagmsg_len == 0) {
1542 			(*tag)->tagmsg = strdup("");
1543 			if ((*tag)->tagmsg == NULL) {
1544 				err = got_error_from_errno("strdup");
1545 				break;
1546 			}
1547 		} else {
1548 			size_t offset = 0, remain = itag->tagmsg_len;
1549 
1550 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1551 			if ((*tag)->tagmsg == NULL) {
1552 				err = got_error_from_errno("malloc");
1553 				break;
1554 			}
1555 			while (remain > 0) {
1556 				struct imsg imsg_log;
1557 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1558 				    remain);
1559 
1560 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1561 				if (err)
1562 					return err;
1563 
1564 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1565 					return got_error(GOT_ERR_PRIVSEP_MSG);
1566 
1567 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1568 				    n);
1569 				imsg_free(&imsg_log);
1570 				offset += n;
1571 				remain -= n;
1572 			}
1573 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1574 		}
1575 
1576 		break;
1577 	default:
1578 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1579 		break;
1580 	}
1581 
1582 	imsg_free(&imsg);
1583 
1584 	return err;
1585 }
1586 
1587 const struct got_error *
1588 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1589     struct got_packidx *packidx)
1590 {
1591 	const struct got_error *err = NULL;
1592 	struct got_imsg_packidx ipackidx;
1593 	struct got_imsg_pack ipack;
1594 	int fd;
1595 
1596 	ipackidx.len = packidx->len;
1597 	fd = dup(packidx->fd);
1598 	if (fd == -1)
1599 		return got_error_from_errno("dup");
1600 
1601 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
1602 	    sizeof(ipackidx)) == -1) {
1603 		err = got_error_from_errno("imsg_compose PACKIDX");
1604 		close(fd);
1605 		return err;
1606 	}
1607 
1608 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
1609 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
1610 		return got_error(GOT_ERR_NO_SPACE);
1611 	ipack.filesize = pack->filesize;
1612 
1613 	fd = dup(pack->fd);
1614 	if (fd == -1)
1615 		return got_error_from_errno("dup");
1616 
1617 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
1618 	    == -1) {
1619 		err = got_error_from_errno("imsg_compose PACK");
1620 		close(fd);
1621 		return err;
1622 	}
1623 
1624 	return flush_imsg(ibuf);
1625 }
1626 
1627 const struct got_error *
1628 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
1629     struct got_object_id *id)
1630 {
1631 	struct got_imsg_packed_object iobj;
1632 
1633 	iobj.idx = idx;
1634 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
1635 
1636 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
1637 	    &iobj, sizeof(iobj)) == -1)
1638 		return got_error_from_errno("imsg_compose "
1639 		    "PACKED_OBJECT_REQUEST");
1640 
1641 	return flush_imsg(ibuf);
1642 }
1643 
1644 const struct got_error *
1645 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
1646 {
1647 	const struct got_error *err = NULL;
1648 
1649 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
1650 	    NULL, 0) == -1) {
1651 		err = got_error_from_errno("imsg_compose "
1652 		    "GITCONFIG_PARSE_REQUEST");
1653 		close(fd);
1654 		return err;
1655 	}
1656 
1657 	return flush_imsg(ibuf);
1658 }
1659 
1660 const struct got_error *
1661 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
1662 {
1663 	if (imsg_compose(ibuf,
1664 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
1665 	    NULL, 0) == -1)
1666 		return got_error_from_errno("imsg_compose "
1667 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
1668 
1669 	return flush_imsg(ibuf);
1670 }
1671 
1672 const struct got_error *
1673 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
1674 {
1675 	if (imsg_compose(ibuf,
1676 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
1677 		return got_error_from_errno("imsg_compose "
1678 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
1679 
1680 	return flush_imsg(ibuf);
1681 }
1682 
1683 const struct got_error *
1684 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
1685 {
1686 	if (imsg_compose(ibuf,
1687 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
1688 		return got_error_from_errno("imsg_compose "
1689 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
1690 
1691 	return flush_imsg(ibuf);
1692 }
1693 
1694 const struct got_error *
1695 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
1696 {
1697 	if (imsg_compose(ibuf,
1698 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
1699 		return got_error_from_errno("imsg_compose "
1700 		    "GITCONFIG_REMOTE_REQUEST");
1701 
1702 	return flush_imsg(ibuf);
1703 }
1704 
1705 const struct got_error *
1706 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
1707 {
1708 	if (imsg_compose(ibuf,
1709 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
1710 		return got_error_from_errno("imsg_compose "
1711 		    "GITCONFIG_OWNER_REQUEST");
1712 
1713 	return flush_imsg(ibuf);
1714 }
1715 
1716 const struct got_error *
1717 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
1718 {
1719 	const struct got_error *err = NULL;
1720 	struct imsg imsg;
1721 	size_t datalen;
1722 	const size_t min_datalen = 0;
1723 
1724 	*str = NULL;
1725 
1726 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1727 	if (err)
1728 		return err;
1729 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1730 
1731 	switch (imsg.hdr.type) {
1732 	case GOT_IMSG_GITCONFIG_STR_VAL:
1733 		if (datalen == 0)
1734 			break;
1735 		*str = malloc(datalen);
1736 		if (*str == NULL) {
1737 			err = got_error_from_errno("malloc");
1738 			break;
1739 		}
1740 		if (strlcpy(*str, imsg.data, datalen) >= datalen)
1741 			err = got_error(GOT_ERR_NO_SPACE);
1742 		break;
1743 	default:
1744 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1745 		break;
1746 	}
1747 
1748 	imsg_free(&imsg);
1749 	return err;
1750 }
1751 
1752 const struct got_error *
1753 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
1754 {
1755 	const struct got_error *err = NULL;
1756 	struct imsg imsg;
1757 	size_t datalen;
1758 	const size_t min_datalen =
1759 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
1760 
1761 	*val = 0;
1762 
1763 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1764 	if (err)
1765 		return err;
1766 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1767 
1768 	switch (imsg.hdr.type) {
1769 	case GOT_IMSG_GITCONFIG_INT_VAL:
1770 		if (datalen != sizeof(*val)) {
1771 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1772 			break;
1773 		}
1774 		memcpy(val, imsg.data, sizeof(*val));
1775 		break;
1776 	default:
1777 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1778 		break;
1779 	}
1780 
1781 	imsg_free(&imsg);
1782 	return err;
1783 }
1784 
1785 const struct got_error *
1786 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
1787     int *nremotes, struct imsgbuf *ibuf)
1788 {
1789 	const struct got_error *err = NULL;
1790 	struct imsg imsg;
1791 	size_t datalen;
1792 	struct got_imsg_remotes iremotes;
1793 	struct got_imsg_remote iremote;
1794 
1795 	*remotes = NULL;
1796 	*nremotes = 0;
1797 	iremotes.nremotes = 0;
1798 
1799 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
1800 	if (err)
1801 		return err;
1802 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1803 
1804 	switch (imsg.hdr.type) {
1805 	case GOT_IMSG_GITCONFIG_REMOTES:
1806 		if (datalen != sizeof(iremotes)) {
1807 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1808 			break;
1809 		}
1810 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
1811 		if (iremotes.nremotes == 0) {
1812 			imsg_free(&imsg);
1813 			return NULL;
1814 		}
1815 		break;
1816 	default:
1817 		imsg_free(&imsg);
1818 		return got_error(GOT_ERR_PRIVSEP_MSG);
1819 	}
1820 
1821 	imsg_free(&imsg);
1822 
1823 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
1824 	if (*remotes == NULL)
1825 		return got_error_from_errno("recallocarray");
1826 
1827 	while (*nremotes < iremotes.nremotes) {
1828 		struct got_remote_repo *remote;
1829 	
1830 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
1831 		if (err)
1832 			break;
1833 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1834 
1835 		switch (imsg.hdr.type) {
1836 		case GOT_IMSG_GITCONFIG_REMOTE:
1837 			remote = &(*remotes)[*nremotes];
1838 			if (datalen < sizeof(iremote)) {
1839 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1840 				break;
1841 			}
1842 			memcpy(&iremote, imsg.data, sizeof(iremote));
1843 			if (iremote.name_len == 0 || iremote.url_len == 0 ||
1844 			    (sizeof(iremote) + iremote.name_len +
1845 			    iremote.url_len) > datalen) {
1846 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1847 				break;
1848 			}
1849 			remote->name = strndup(imsg.data + sizeof(iremote),
1850 			    iremote.name_len);
1851 			if (remote->name == NULL) {
1852 				err = got_error_from_errno("strndup");
1853 				break;
1854 			}
1855 			remote->url = strndup(imsg.data + sizeof(iremote) +
1856 			    iremote.name_len, iremote.url_len);
1857 			if (remote->url == NULL) {
1858 				err = got_error_from_errno("strndup");
1859 				free(remote->name);
1860 				break;
1861 			}
1862 			remote->mirror_references = iremote.mirror_references;
1863 			(*nremotes)++;
1864 			break;
1865 		default:
1866 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1867 			break;
1868 		}
1869 
1870 		imsg_free(&imsg);
1871 		if (err)
1872 			break;
1873 	}
1874 
1875 	if (err) {
1876 		int i;
1877 		for (i = 0; i < *nremotes; i++) {
1878 			free((*remotes)[i].name);
1879 			free((*remotes)[i].url);
1880 		}
1881 		free(*remotes);
1882 		*remotes = NULL;
1883 		*nremotes = 0;
1884 	}
1885 	return err;
1886 }
1887 
1888 const struct got_error *
1889 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
1890      struct got_object_id *id, int idx, const char *path)
1891 {
1892 	const struct got_error *err = NULL;
1893 	struct ibuf *wbuf;
1894 	size_t path_len = strlen(path) + 1;
1895 
1896 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
1897 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
1898 	if (wbuf == NULL)
1899 		return got_error_from_errno(
1900 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
1901 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
1902 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
1903 		ibuf_free(wbuf);
1904 		return err;
1905 	}
1906 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1) {
1907 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
1908 		ibuf_free(wbuf);
1909 		return err;
1910 	}
1911 	if (imsg_add(wbuf, path, path_len) == -1) {
1912 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
1913 		ibuf_free(wbuf);
1914 		return err;
1915 	}
1916 
1917 	wbuf->fd = -1;
1918 	imsg_close(ibuf, wbuf);
1919 
1920 	return flush_imsg(ibuf);
1921 }
1922 
1923 const struct got_error *
1924 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
1925     struct got_object_id **changed_commit_id,
1926     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
1927 {
1928 	const struct got_error *err = NULL;
1929 	struct imsg imsg;
1930 	struct got_imsg_traversed_commits *icommits;
1931 	size_t datalen;
1932 	int i, done = 0;
1933 
1934 	*changed_commit = NULL;
1935 	*changed_commit_id = NULL;
1936 
1937 	while (!done) {
1938 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1939 		if (err)
1940 			return err;
1941 
1942 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1943 		switch (imsg.hdr.type) {
1944 		case GOT_IMSG_TRAVERSED_COMMITS:
1945 			icommits = imsg.data;
1946 			if (datalen != sizeof(*icommits) +
1947 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
1948 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1949 				break;
1950 			}
1951 			for (i = 0; i < icommits->ncommits; i++) {
1952 				struct got_object_qid *qid;
1953 				uint8_t *sha1 = (uint8_t *)imsg.data +
1954 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
1955 				err = got_object_qid_alloc_partial(&qid);
1956 				if (err)
1957 					break;
1958 				memcpy(qid->id->sha1, sha1, SHA1_DIGEST_LENGTH);
1959 				SIMPLEQ_INSERT_TAIL(commit_ids, qid, entry);
1960 
1961 				/* The last commit may contain a change. */
1962 				if (i == icommits->ncommits - 1) {
1963 					*changed_commit_id =
1964 					    got_object_id_dup(qid->id);
1965 					if (*changed_commit_id == NULL) {
1966 						err = got_error_from_errno(
1967 						    "got_object_id_dup");
1968 						break;
1969 					}
1970 				}
1971 			}
1972 			break;
1973 		case GOT_IMSG_COMMIT:
1974 			if (*changed_commit_id == NULL) {
1975 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1976 				break;
1977 			}
1978 			err = get_commit_from_imsg(changed_commit, &imsg,
1979 			    datalen, ibuf);
1980 			break;
1981 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
1982 			done = 1;
1983 			break;
1984 		default:
1985 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1986 			break;
1987 		}
1988 
1989 		imsg_free(&imsg);
1990 		if (err)
1991 			break;
1992 	}
1993 
1994 	if (err)
1995 		got_object_id_queue_free(commit_ids);
1996 	return err;
1997 }
1998 
1999 const struct got_error *
2000 got_privsep_unveil_exec_helpers(void)
2001 {
2002 	const char *helpers[] = {
2003 	    GOT_PATH_PROG_READ_PACK,
2004 	    GOT_PATH_PROG_READ_OBJECT,
2005 	    GOT_PATH_PROG_READ_COMMIT,
2006 	    GOT_PATH_PROG_READ_TREE,
2007 	    GOT_PATH_PROG_READ_BLOB,
2008 	    GOT_PATH_PROG_READ_TAG,
2009 	    GOT_PATH_PROG_READ_GITCONFIG,
2010 	    GOT_PATH_PROG_FETCH_PACK,
2011 	    GOT_PATH_PROG_INDEX_PACK,
2012 	};
2013 	int i;
2014 
2015 	for (i = 0; i < nitems(helpers); i++) {
2016 		if (unveil(helpers[i], "x") == 0)
2017 			continue;
2018 		return got_error_from_errno2("unveil", helpers[i]);
2019 	}
2020 
2021 	return NULL;
2022 }
2023 
2024 void
2025 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
2026 {
2027 	if (close(imsg_fds[0]) != 0) {
2028 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2029 		_exit(1);
2030 	}
2031 
2032 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
2033 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2034 		_exit(1);
2035 	}
2036 	if (closefrom(GOT_IMSG_FD_CHILD + 1) == -1) {
2037 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2038 		_exit(1);
2039 	}
2040 
2041 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
2042 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
2043 		    strerror(errno));
2044 		_exit(1);
2045 	}
2046 }