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Date:: Thu Jul 8 11:03:29 2021 UTC
Message:: verify object ID checksums while loose objects are being accessed
Actions:: History | Blame | Raw File
1 /*
2  * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
3  * Copyright (c) 2020 Ori Bernstein <ori@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/types.h>
19 #include <sys/queue.h>
20 #include <sys/uio.h>
21 #include <sys/wait.h>
22 
23 #include <ctype.h>
24 #include <limits.h>
25 #include <signal.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <errno.h>
30 #include <stdint.h>
31 #include <poll.h>
32 #include <imsg.h>
33 #include <sha1.h>
34 #include <unistd.h>
35 #include <zlib.h>
36 #include <time.h>
37 
38 #include "got_object.h"
39 #include "got_error.h"
40 #include "got_path.h"
41 #include "got_repository.h"
42 
43 #include "got_lib_sha1.h"
44 #include "got_lib_delta.h"
45 #include "got_lib_inflate.h"
46 #include "got_lib_object.h"
47 #include "got_lib_object_parse.h"
48 #include "got_lib_privsep.h"
49 #include "got_lib_pack.h"
50 
51 #ifndef MIN
52 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
53 #endif
54 
55 #ifndef nitems
56 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
57 #endif
58 
59 static const struct got_error *
60 poll_fd(int fd, int events, int timeout)
61 {
62 	struct pollfd pfd[1];
63 	struct timespec ts;
64 	sigset_t sigset;
65 	int n;
66 
67 	pfd[0].fd = fd;
68 	pfd[0].events = events;
69 
70 	ts.tv_sec = timeout;
71 	ts.tv_nsec = 0;
72 
73 	if (sigemptyset(&sigset) == -1)
74 		return got_error_from_errno("sigemptyset");
75 	if (sigaddset(&sigset, SIGWINCH) == -1)
76 		return got_error_from_errno("sigaddset");
77 
78 	n = ppoll(pfd, 1, timeout == INFTIM ? NULL : &ts, &sigset);
79 	if (n == -1)
80 		return got_error_from_errno("ppoll");
81 	if (n == 0)
82 		return got_error(GOT_ERR_TIMEOUT);
83 	if (pfd[0].revents & (POLLERR | POLLNVAL))
84 		return got_error_from_errno("poll error");
85 	if (pfd[0].revents & (events | POLLHUP))
86 		return NULL;
87 
88 	return got_error(GOT_ERR_INTERRUPT);
89 }
90 
91 static const struct got_error *
92 read_imsg(struct imsgbuf *ibuf)
93 {
94 	const struct got_error *err;
95 	size_t n;
96 
97 	err = poll_fd(ibuf->fd, POLLIN, INFTIM);
98 	if (err)
99 		return err;
100 
101 	n = imsg_read(ibuf);
102 	if (n == -1) {
103 		if (errno == EAGAIN) /* Could be a file-descriptor leak. */
104 			return got_error(GOT_ERR_PRIVSEP_NO_FD);
105 		return got_error(GOT_ERR_PRIVSEP_READ);
106 	}
107 	if (n == 0)
108 		return got_error(GOT_ERR_PRIVSEP_PIPE);
109 
110 	return NULL;
111 }
112 
113 const struct got_error *
114 got_privsep_wait_for_child(pid_t pid)
115 {
116 	int child_status;
117 
118 	if (waitpid(pid, &child_status, 0) == -1)
119 		return got_error_from_errno("waitpid");
120 
121 	if (!WIFEXITED(child_status))
122 		return got_error(GOT_ERR_PRIVSEP_DIED);
123 
124 	if (WEXITSTATUS(child_status) != 0)
125 		return got_error(GOT_ERR_PRIVSEP_EXIT);
126 
127 	return NULL;
128 }
129 
130 static const struct got_error *
131 recv_imsg_error(struct imsg *imsg, size_t datalen)
132 {
133 	struct got_imsg_error *ierr;
134 
135 	if (datalen != sizeof(*ierr))
136 		return got_error(GOT_ERR_PRIVSEP_LEN);
137 
138 	ierr = imsg->data;
139 	if (ierr->code == GOT_ERR_ERRNO) {
140 		static struct got_error serr;
141 		serr.code = GOT_ERR_ERRNO;
142 		serr.msg = strerror(ierr->errno_code);
143 		return &serr;
144 	}
145 
146 	return got_error(ierr->code);
147 }
148 
149 const struct got_error *
150 got_privsep_recv_imsg(struct imsg *imsg, struct imsgbuf *ibuf,
151     size_t min_datalen)
152 {
153 	const struct got_error *err;
154 	ssize_t n;
155 
156 	n = imsg_get(ibuf, imsg);
157 	if (n == -1)
158 		return got_error_from_errno("imsg_get");
159 
160 	while (n == 0) {
161 		err = read_imsg(ibuf);
162 		if (err)
163 			return err;
164 		n = imsg_get(ibuf, imsg);
165 		if (n == -1)
166 			return got_error_from_errno("imsg_get");
167 	}
168 
169 	if (imsg->hdr.len < IMSG_HEADER_SIZE + min_datalen)
170 		return got_error(GOT_ERR_PRIVSEP_LEN);
171 
172 	if (imsg->hdr.type == GOT_IMSG_ERROR) {
173 		size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
174 		return recv_imsg_error(imsg, datalen);
175 	}
176 
177 	return NULL;
178 }
179 
180 /* Attempt to send an error in an imsg. Complain on stderr as a last resort. */
181 void
182 got_privsep_send_error(struct imsgbuf *ibuf, const struct got_error *err)
183 {
184 	const struct got_error *poll_err;
185 	struct got_imsg_error ierr;
186 	int ret;
187 
188 	ierr.code = err->code;
189 	if (err->code == GOT_ERR_ERRNO)
190 		ierr.errno_code = errno;
191 	else
192 		ierr.errno_code = 0;
193 	ret = imsg_compose(ibuf, GOT_IMSG_ERROR, 0, 0, -1, &ierr, sizeof(ierr));
194 	if (ret == -1) {
195 		fprintf(stderr, "%s: error %d \"%s\": imsg_compose: %s\n",
196 		    getprogname(), err->code, err->msg, strerror(errno));
197 		return;
198 	}
199 
200 	poll_err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
201 	if (poll_err) {
202 		fprintf(stderr, "%s: error %d \"%s\": poll: %s\n",
203 		    getprogname(), err->code, err->msg, poll_err->msg);
204 		return;
205 	}
206 
207 	ret = imsg_flush(ibuf);
208 	if (ret == -1) {
209 		fprintf(stderr, "%s: error %d \"%s\": imsg_flush: %s\n",
210 		    getprogname(), err->code, err->msg, strerror(errno));
211 		return;
212 	}
213 }
214 
215 static const struct got_error *
216 flush_imsg(struct imsgbuf *ibuf)
217 {
218 	const struct got_error *err;
219 
220 	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
221 	if (err)
222 		return err;
223 
224 	if (imsg_flush(ibuf) == -1)
225 		return got_error_from_errno("imsg_flush");
226 
227 	return NULL;
228 }
229 
230 const struct got_error *
231 got_privsep_flush_imsg(struct imsgbuf *ibuf)
232 {
233 	return flush_imsg(ibuf);
234 }
235 
236 const struct got_error *
237 got_privsep_send_stop(int fd)
238 {
239 	const struct got_error *err = NULL;
240 	struct imsgbuf ibuf;
241 
242 	imsg_init(&ibuf, fd);
243 
244 	if (imsg_compose(&ibuf, GOT_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
245 		return got_error_from_errno("imsg_compose STOP");
246 
247 	err = flush_imsg(&ibuf);
248 	imsg_clear(&ibuf);
249 	return err;
250 }
251 
252 const struct got_error *
253 got_privsep_send_obj_req(struct imsgbuf *ibuf, int fd,
254     struct got_object_id *id)
255 {
256 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_REQUEST, 0, 0, fd,
257 	    id, sizeof(*id)) == -1)
258 		return got_error_from_errno("imsg_compose OBJECT_REQUEST");
259 
260 	return flush_imsg(ibuf);
261 }
262 
263 const struct got_error *
264 got_privsep_send_raw_obj_req(struct imsgbuf *ibuf, int fd,
265     struct got_object_id *id)
266 {
267 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_REQUEST, 0, 0, fd,
268 	    id, sizeof(*id)) == -1)
269 		return got_error_from_errno("imsg_compose RAW_OBJECT_REQUEST");
270 
271 	return flush_imsg(ibuf);
272 }
273 
274 const struct got_error *
275 got_privsep_send_raw_obj_outfd(struct imsgbuf *ibuf, int outfd)
276 {
277 	const struct got_error *err = NULL;
278 
279 	if (imsg_compose(ibuf, GOT_IMSG_RAW_OBJECT_OUTFD, 0, 0, outfd, NULL, 0)
280 	    == -1) {
281 		err = got_error_from_errno("imsg_compose RAW_OBJECT_OUTFD");
282 		close(outfd);
283 		return err;
284 	}
285 
286 	return flush_imsg(ibuf);
287 }
288 
289 const struct got_error *
290 got_privsep_send_raw_obj(struct imsgbuf *ibuf, off_t size, size_t hdrlen,
291     uint8_t *data)
292 {
293 	const struct got_error *err = NULL;
294 	struct got_imsg_raw_obj iobj;
295 	size_t len = sizeof(iobj);
296 	struct ibuf *wbuf;
297 
298 	iobj.hdrlen = hdrlen;
299 	iobj.size = size;
300 
301 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX)
302 		len += (size_t)size + hdrlen;
303 
304 	wbuf = imsg_create(ibuf, GOT_IMSG_RAW_OBJECT, 0, 0, len);
305 	if (wbuf == NULL) {
306 		err = got_error_from_errno("imsg_create RAW_OBJECT");
307 		return err;
308 	}
309 
310 	if (imsg_add(wbuf, &iobj, sizeof(iobj)) == -1) {
311 		err = got_error_from_errno("imsg_add RAW_OBJECT");
312 		ibuf_free(wbuf);
313 		return err;
314 	}
315 
316 	if (data && size + hdrlen <= GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
317 		if (imsg_add(wbuf, data, size + hdrlen) == -1) {
318 			err = got_error_from_errno("imsg_add RAW_OBJECT");
319 			ibuf_free(wbuf);
320 			return err;
321 		}
322 	}
323 
324 	wbuf->fd = -1;
325 	imsg_close(ibuf, wbuf);
326 
327 	return flush_imsg(ibuf);
328 }
329 
330 const struct got_error *
331 got_privsep_recv_raw_obj(uint8_t **outbuf, off_t *size, size_t *hdrlen,
332     struct imsgbuf *ibuf)
333 {
334 	const struct got_error *err = NULL;
335 	struct imsg imsg;
336 	struct got_imsg_raw_obj *iobj;
337 	size_t datalen;
338 
339 	*outbuf = NULL;
340 
341 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
342 	if (err)
343 		return err;
344 
345 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
346 
347 	switch (imsg.hdr.type) {
348 	case GOT_IMSG_RAW_OBJECT:
349 		if (datalen < sizeof(*iobj)) {
350 			err = got_error(GOT_ERR_PRIVSEP_LEN);
351 			break;
352 		}
353 		iobj = imsg.data;
354 		*size = iobj->size;
355 		*hdrlen = iobj->hdrlen;
356 
357 		if (datalen == sizeof(*iobj)) {
358 			/* Data has been written to file descriptor. */
359 			break;
360 		}
361 
362 		if (*size + *hdrlen > GOT_PRIVSEP_INLINE_OBJECT_DATA_MAX) {
363 			err = got_error(GOT_ERR_PRIVSEP_LEN);
364 			break;
365 		}
366 
367 		*outbuf = malloc(*size + *hdrlen);
368 		if (*outbuf == NULL) {
369 			err = got_error_from_errno("malloc");
370 			break;
371 		}
372 		memcpy(*outbuf, imsg.data + sizeof(*iobj), *size + *hdrlen);
373 		break;
374 	default:
375 		err = got_error(GOT_ERR_PRIVSEP_MSG);
376 		break;
377 	}
378 
379 	imsg_free(&imsg);
380 
381 	return err;
382 }
383 
384 const struct got_error *
385 got_privsep_send_commit_req(struct imsgbuf *ibuf, int fd,
386     struct got_object_id *id, int pack_idx)
387 {
388 	const struct got_error *err = NULL;
389 	struct got_imsg_packed_object iobj;
390 	void *data;
391 	size_t len;
392 
393 	if (pack_idx != -1) { /* commit is packed */
394 		iobj.idx = pack_idx;
395 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
396 		data = &iobj;
397 		len = sizeof(iobj);
398 	} else {
399 		data = id;
400 		len = sizeof(*id);
401 	}
402 
403 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_REQUEST, 0, 0, fd, data, len)
404 	    == -1) {
405 		err = got_error_from_errno("imsg_compose COMMIT_REQUEST");
406 		close(fd);
407 		return err;
408 	}
409 
410 	return flush_imsg(ibuf);
411 }
412 
413 const struct got_error *
414 got_privsep_send_tree_req(struct imsgbuf *ibuf, int fd,
415     struct got_object_id *id, int pack_idx)
416 {
417 	const struct got_error *err = NULL;
418 	struct ibuf *wbuf;
419 	size_t len;
420 
421 	if (pack_idx != -1)
422 		len = sizeof(struct got_imsg_packed_object);
423 	else
424 		len = sizeof(*id);
425 
426 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_REQUEST, 0, 0, len);
427 	if (wbuf == NULL)
428 		return got_error_from_errno("imsg_create TREE_REQUEST");
429 
430 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
431 		err = got_error_from_errno("imsg_add TREE_ENTRY");
432 		ibuf_free(wbuf);
433 		return err;
434 	}
435 
436 	if (pack_idx != -1) { /* tree is packed */
437 		if (imsg_add(wbuf, &pack_idx, sizeof(pack_idx)) == -1) {
438 			err = got_error_from_errno("imsg_add TREE_ENTRY");
439 			ibuf_free(wbuf);
440 			return err;
441 		}
442 	}
443 
444 	wbuf->fd = fd;
445 	imsg_close(ibuf, wbuf);
446 
447 	return flush_imsg(ibuf);
448 }
449 
450 const struct got_error *
451 got_privsep_send_tag_req(struct imsgbuf *ibuf, int fd,
452     struct got_object_id *id, int pack_idx)
453 {
454 	struct got_imsg_packed_object iobj;
455 	void *data;
456 	size_t len;
457 
458 	if (pack_idx != -1) { /* tag is packed */
459 		iobj.idx = pack_idx;
460 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
461 		data = &iobj;
462 		len = sizeof(iobj);
463 	} else {
464 		data = id;
465 		len = sizeof(*id);
466 	}
467 
468 	if (imsg_compose(ibuf, GOT_IMSG_TAG_REQUEST, 0, 0, fd, data, len)
469 	    == -1)
470 		return got_error_from_errno("imsg_compose TAG_REQUEST");
471 
472 	return flush_imsg(ibuf);
473 }
474 
475 const struct got_error *
476 got_privsep_send_blob_req(struct imsgbuf *ibuf, int infd,
477     struct got_object_id *id, int pack_idx)
478 {
479 	const struct got_error *err = NULL;
480 	struct got_imsg_packed_object iobj;
481 	void *data;
482 	size_t len;
483 
484 	if (pack_idx != -1) { /* blob is packed */
485 		iobj.idx = pack_idx;
486 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
487 		data = &iobj;
488 		len = sizeof(iobj);
489 	} else {
490 		data = id;
491 		len = sizeof(*id);
492 	}
493 
494 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_REQUEST, 0, 0, infd, data, len)
495 	    == -1) {
496 		err = got_error_from_errno("imsg_compose BLOB_REQUEST");
497 		close(infd);
498 		return err;
499 	}
500 
501 	return flush_imsg(ibuf);
502 }
503 
504 const struct got_error *
505 got_privsep_send_blob_outfd(struct imsgbuf *ibuf, int outfd)
506 {
507 	const struct got_error *err = NULL;
508 
509 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_OUTFD, 0, 0, outfd, NULL, 0)
510 	    == -1) {
511 		err = got_error_from_errno("imsg_compose BLOB_OUTFD");
512 		close(outfd);
513 		return err;
514 	}
515 
516 	return flush_imsg(ibuf);
517 }
518 
519 static const struct got_error *
520 send_fd(struct imsgbuf *ibuf, int imsg_code, int fd)
521 {
522 	const struct got_error *err = NULL;
523 
524 	if (imsg_compose(ibuf, imsg_code, 0, 0, fd, NULL, 0) == -1) {
525 		err = got_error_from_errno("imsg_compose TMPFD");
526 		close(fd);
527 		return err;
528 	}
529 
530 	return flush_imsg(ibuf);
531 }
532 
533 const struct got_error *
534 got_privsep_send_tmpfd(struct imsgbuf *ibuf, int fd)
535 {
536 	return send_fd(ibuf, GOT_IMSG_TMPFD, fd);
537 }
538 
539 const struct got_error *
540 got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj)
541 {
542 	struct got_imsg_object iobj;
543 
544 	memcpy(iobj.id, obj->id.sha1, sizeof(iobj.id));
545 	iobj.type = obj->type;
546 	iobj.flags = obj->flags;
547 	iobj.hdrlen = obj->hdrlen;
548 	iobj.size = obj->size;
549 	if (iobj.flags & GOT_OBJ_FLAG_PACKED) {
550 		iobj.pack_offset = obj->pack_offset;
551 		iobj.pack_idx = obj->pack_idx;
552 	}
553 
554 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
555 	    == -1)
556 		return got_error_from_errno("imsg_compose OBJECT");
557 
558 	return flush_imsg(ibuf);
559 }
560 
561 const struct got_error *
562 got_privsep_send_fetch_req(struct imsgbuf *ibuf, int fd,
563    struct got_pathlist_head *have_refs, int fetch_all_branches,
564    struct got_pathlist_head *wanted_branches,
565    struct got_pathlist_head *wanted_refs, int list_refs_only, int verbosity)
566 {
567 	const struct got_error *err = NULL;
568 	struct ibuf *wbuf;
569 	size_t len;
570 	struct got_pathlist_entry *pe;
571 	struct got_imsg_fetch_request fetchreq;
572 
573 	memset(&fetchreq, 0, sizeof(fetchreq));
574 	fetchreq.fetch_all_branches = fetch_all_branches;
575 	fetchreq.list_refs_only = list_refs_only;
576 	fetchreq.verbosity = verbosity;
577 	TAILQ_FOREACH(pe, have_refs, entry)
578 		fetchreq.n_have_refs++;
579 	TAILQ_FOREACH(pe, wanted_branches, entry)
580 		fetchreq.n_wanted_branches++;
581 	TAILQ_FOREACH(pe, wanted_refs, entry)
582 		fetchreq.n_wanted_refs++;
583 	len = sizeof(struct got_imsg_fetch_request);
584 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
585 		close(fd);
586 		return got_error(GOT_ERR_NO_SPACE);
587 	}
588 
589 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_REQUEST, 0, 0, fd,
590 	    &fetchreq, sizeof(fetchreq)) == -1)
591 		return got_error_from_errno(
592 		    "imsg_compose FETCH_SERVER_PROGRESS");
593 
594 	err = flush_imsg(ibuf);
595 	if (err) {
596 		close(fd);
597 		return err;
598 	}
599 	fd = -1;
600 
601 	TAILQ_FOREACH(pe, have_refs, entry) {
602 		const char *name = pe->path;
603 		size_t name_len = pe->path_len;
604 		struct got_object_id *id = pe->data;
605 
606 		len = sizeof(struct got_imsg_fetch_have_ref) + name_len;
607 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_HAVE_REF, 0, 0, len);
608 		if (wbuf == NULL)
609 			return got_error_from_errno("imsg_create FETCH_HAVE_REF");
610 
611 		/* Keep in sync with struct got_imsg_fetch_have_ref! */
612 		if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1) {
613 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
614 			ibuf_free(wbuf);
615 			return err;
616 		}
617 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
618 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
619 			ibuf_free(wbuf);
620 			return err;
621 		}
622 		if (imsg_add(wbuf, name, name_len) == -1) {
623 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
624 			ibuf_free(wbuf);
625 			return err;
626 		}
627 
628 		wbuf->fd = -1;
629 		imsg_close(ibuf, wbuf);
630 		err = flush_imsg(ibuf);
631 		if (err)
632 			return err;
633 	}
634 
635 	TAILQ_FOREACH(pe, wanted_branches, entry) {
636 		const char *name = pe->path;
637 		size_t name_len = pe->path_len;
638 
639 		len = sizeof(struct got_imsg_fetch_wanted_branch) + name_len;
640 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_BRANCH, 0, 0,
641 		    len);
642 		if (wbuf == NULL)
643 			return got_error_from_errno(
644 			    "imsg_create FETCH_WANTED_BRANCH");
645 
646 		/* Keep in sync with struct got_imsg_fetch_wanted_branch! */
647 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
648 			err = got_error_from_errno(
649 			    "imsg_add FETCH_WANTED_BRANCH");
650 			ibuf_free(wbuf);
651 			return err;
652 		}
653 		if (imsg_add(wbuf, name, name_len) == -1) {
654 			err = got_error_from_errno(
655 			    "imsg_add FETCH_WANTED_BRANCH");
656 			ibuf_free(wbuf);
657 			return err;
658 		}
659 
660 		wbuf->fd = -1;
661 		imsg_close(ibuf, wbuf);
662 		err = flush_imsg(ibuf);
663 		if (err)
664 			return err;
665 	}
666 
667 	TAILQ_FOREACH(pe, wanted_refs, entry) {
668 		const char *name = pe->path;
669 		size_t name_len = pe->path_len;
670 
671 		len = sizeof(struct got_imsg_fetch_wanted_ref) + name_len;
672 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_REF, 0, 0,
673 		    len);
674 		if (wbuf == NULL)
675 			return got_error_from_errno(
676 			    "imsg_create FETCH_WANTED_REF");
677 
678 		/* Keep in sync with struct got_imsg_fetch_wanted_ref! */
679 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
680 			err = got_error_from_errno(
681 			    "imsg_add FETCH_WANTED_REF");
682 			ibuf_free(wbuf);
683 			return err;
684 		}
685 		if (imsg_add(wbuf, name, name_len) == -1) {
686 			err = got_error_from_errno(
687 			    "imsg_add FETCH_WANTED_REF");
688 			ibuf_free(wbuf);
689 			return err;
690 		}
691 
692 		wbuf->fd = -1;
693 		imsg_close(ibuf, wbuf);
694 		err = flush_imsg(ibuf);
695 		if (err)
696 			return err;
697 	}
698 
699 
700 	return NULL;
701 
702 }
703 
704 const struct got_error *
705 got_privsep_send_fetch_outfd(struct imsgbuf *ibuf, int fd)
706 {
707 	return send_fd(ibuf, GOT_IMSG_FETCH_OUTFD, fd);
708 }
709 
710 const struct got_error *
711 got_privsep_recv_fetch_progress(int *done, struct got_object_id **id,
712     char **refname, struct got_pathlist_head *symrefs, char **server_progress,
713     off_t *packfile_size, uint8_t *pack_sha1, struct imsgbuf *ibuf)
714 {
715 	const struct got_error *err = NULL;
716 	struct imsg imsg;
717 	size_t datalen;
718 	struct got_imsg_fetch_symrefs *isymrefs = NULL;
719 	size_t n, remain;
720 	off_t off;
721 	int i;
722 
723 	*done = 0;
724 	*id = NULL;
725 	*refname = NULL;
726 	*server_progress = NULL;
727 	*packfile_size = 0;
728 	memset(pack_sha1, 0, SHA1_DIGEST_LENGTH);
729 
730 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
731 	if (err)
732 		return err;
733 
734 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
735 	switch (imsg.hdr.type) {
736 	case GOT_IMSG_ERROR:
737 		if (datalen < sizeof(struct got_imsg_error)) {
738 			err = got_error(GOT_ERR_PRIVSEP_LEN);
739 			break;
740 		}
741 		err = recv_imsg_error(&imsg, datalen);
742 		break;
743 	case GOT_IMSG_FETCH_SYMREFS:
744 		if (datalen < sizeof(*isymrefs)) {
745 			err = got_error(GOT_ERR_PRIVSEP_LEN);
746 			break;
747 		}
748 		if (isymrefs != NULL) {
749 			err = got_error(GOT_ERR_PRIVSEP_MSG);
750 			break;
751 		}
752 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
753 		off = sizeof(*isymrefs);
754 		remain = datalen - off;
755 		for (n = 0; n < isymrefs->nsymrefs; n++) {
756 			struct got_imsg_fetch_symref *s;
757 			char *name, *target;
758 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
759 				err = got_error(GOT_ERR_PRIVSEP_LEN);
760 				goto done;
761 			}
762 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
763 			off += sizeof(*s);
764 			remain -= sizeof(*s);
765 			if (remain < s->name_len) {
766 				err = got_error(GOT_ERR_PRIVSEP_LEN);
767 				goto done;
768 			}
769 			name = strndup(imsg.data + off, s->name_len);
770 			if (name == NULL) {
771 				err = got_error_from_errno("strndup");
772 				goto done;
773 			}
774 			off += s->name_len;
775 			remain -= s->name_len;
776 			if (remain < s->target_len) {
777 				err = got_error(GOT_ERR_PRIVSEP_LEN);
778 				free(name);
779 				goto done;
780 			}
781 			target = strndup(imsg.data + off, s->target_len);
782 			if (target == NULL) {
783 				err = got_error_from_errno("strndup");
784 				free(name);
785 				goto done;
786 			}
787 			off += s->target_len;
788 			remain -= s->target_len;
789 			err = got_pathlist_append(symrefs, name, target);
790 			if (err) {
791 				free(name);
792 				free(target);
793 				goto done;
794 			}
795 		}
796 		break;
797 	case GOT_IMSG_FETCH_REF:
798 		if (datalen <= SHA1_DIGEST_LENGTH) {
799 			err = got_error(GOT_ERR_PRIVSEP_MSG);
800 			break;
801 		}
802 		*id = malloc(sizeof(**id));
803 		if (*id == NULL) {
804 			err = got_error_from_errno("malloc");
805 			break;
806 		}
807 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
808 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
809 		    datalen - SHA1_DIGEST_LENGTH);
810 		if (*refname == NULL) {
811 			err = got_error_from_errno("strndup");
812 			break;
813 		}
814 		break;
815 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
816 		if (datalen == 0) {
817 			err = got_error(GOT_ERR_PRIVSEP_LEN);
818 			break;
819 		}
820 		*server_progress = strndup(imsg.data, datalen);
821 		if (*server_progress == NULL) {
822 			err = got_error_from_errno("strndup");
823 			break;
824 		}
825 		for (i = 0; i < datalen; i++) {
826 			if (!isprint((unsigned char)(*server_progress)[i]) &&
827 			    !isspace((unsigned char)(*server_progress)[i])) {
828 				err = got_error(GOT_ERR_PRIVSEP_MSG);
829 				free(*server_progress);
830 				*server_progress = NULL;
831 				goto done;
832 			}
833 		}
834 		break;
835 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
836 		if (datalen < sizeof(*packfile_size)) {
837 			err = got_error(GOT_ERR_PRIVSEP_MSG);
838 			break;
839 		}
840 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
841 		break;
842 	case GOT_IMSG_FETCH_DONE:
843 		if (datalen != SHA1_DIGEST_LENGTH) {
844 			err = got_error(GOT_ERR_PRIVSEP_MSG);
845 			break;
846 		}
847 		memcpy(pack_sha1, imsg.data, SHA1_DIGEST_LENGTH);
848 		*done = 1;
849 		break;
850 	default:
851 		err = got_error(GOT_ERR_PRIVSEP_MSG);
852 		break;
853 	}
854 done:
855 	if (err) {
856 		free(*id);
857 		*id = NULL;
858 		free(*refname);
859 		*refname = NULL;
860 	}
861 	imsg_free(&imsg);
862 	return err;
863 }
864 
865 const struct got_error *
866 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_sha1,
867     int fd)
868 {
869 	const struct got_error *err = NULL;
870 
871 	/* Keep in sync with struct got_imsg_index_pack_request */
872 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
873 	    pack_sha1, SHA1_DIGEST_LENGTH) == -1) {
874 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
875 		close(fd);
876 		return err;
877 	}
878 	return flush_imsg(ibuf);
879 }
880 
881 const struct got_error *
882 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
883 {
884 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
885 }
886 
887 const struct got_error *
888 got_privsep_recv_index_progress(int *done, int *nobj_total,
889     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
890     struct imsgbuf *ibuf)
891 {
892 	const struct got_error *err = NULL;
893 	struct imsg imsg;
894 	struct got_imsg_index_pack_progress *iprogress;
895 	size_t datalen;
896 
897 	*done = 0;
898 	*nobj_total = 0;
899 	*nobj_indexed = 0;
900 	*nobj_resolved = 0;
901 
902 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
903 	if (err)
904 		return err;
905 
906 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
907 	switch (imsg.hdr.type) {
908 	case GOT_IMSG_ERROR:
909 		if (datalen < sizeof(struct got_imsg_error)) {
910 			err = got_error(GOT_ERR_PRIVSEP_LEN);
911 			break;
912 		}
913 		err = recv_imsg_error(&imsg, datalen);
914 		break;
915 	case GOT_IMSG_IDXPACK_PROGRESS:
916 		if (datalen < sizeof(*iprogress)) {
917 			err = got_error(GOT_ERR_PRIVSEP_LEN);
918 			break;
919 		}
920 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
921 		*nobj_total = iprogress->nobj_total;
922 		*nobj_indexed = iprogress->nobj_indexed;
923 		*nobj_loose = iprogress->nobj_loose;
924 		*nobj_resolved = iprogress->nobj_resolved;
925 		break;
926 	case GOT_IMSG_IDXPACK_DONE:
927 		if (datalen != 0) {
928 			err = got_error(GOT_ERR_PRIVSEP_LEN);
929 			break;
930 		}
931 		*done = 1;
932 		break;
933 	default:
934 		err = got_error(GOT_ERR_PRIVSEP_MSG);
935 		break;
936 	}
937 
938 	imsg_free(&imsg);
939 	return err;
940 }
941 
942 const struct got_error *
943 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
944     struct imsgbuf *ibuf)
945 {
946 	const struct got_error *err = NULL;
947 	struct got_imsg_object *iobj;
948 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
949 
950 	if (datalen != sizeof(*iobj))
951 		return got_error(GOT_ERR_PRIVSEP_LEN);
952 	iobj = imsg->data;
953 
954 	*obj = calloc(1, sizeof(**obj));
955 	if (*obj == NULL)
956 		return got_error_from_errno("calloc");
957 
958 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
959 	(*obj)->type = iobj->type;
960 	(*obj)->flags = iobj->flags;
961 	(*obj)->hdrlen = iobj->hdrlen;
962 	(*obj)->size = iobj->size;
963 	/* path_packfile is handled by caller */
964 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
965 		(*obj)->pack_offset = iobj->pack_offset;
966 		(*obj)->pack_idx = iobj->pack_idx;
967 	}
968 
969 	return err;
970 }
971 
972 const struct got_error *
973 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
974 {
975 	const struct got_error *err = NULL;
976 	struct imsg imsg;
977 	const size_t min_datalen =
978 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
979 
980 	*obj = NULL;
981 
982 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
983 	if (err)
984 		return err;
985 
986 	switch (imsg.hdr.type) {
987 	case GOT_IMSG_OBJECT:
988 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
989 		break;
990 	default:
991 		err = got_error(GOT_ERR_PRIVSEP_MSG);
992 		break;
993 	}
994 
995 	imsg_free(&imsg);
996 
997 	return err;
998 }
999 
1000 static const struct got_error *
1001 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
1002     size_t logmsg_len)
1003 {
1004 	const struct got_error *err = NULL;
1005 	size_t offset, remain;
1006 
1007 	offset = 0;
1008 	remain = logmsg_len;
1009 	while (remain > 0) {
1010 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1011 
1012 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
1013 		    commit->logmsg + offset, n) == -1) {
1014 			err = got_error_from_errno("imsg_compose "
1015 			    "COMMIT_LOGMSG");
1016 			break;
1017 		}
1018 
1019 		err = flush_imsg(ibuf);
1020 		if (err)
1021 			break;
1022 
1023 		offset += n;
1024 		remain -= n;
1025 	}
1026 
1027 	return err;
1028 }
1029 
1030 const struct got_error *
1031 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
1032 {
1033 	const struct got_error *err = NULL;
1034 	struct got_imsg_commit_object *icommit;
1035 	uint8_t *buf;
1036 	size_t len, total;
1037 	struct got_object_qid *qid;
1038 	size_t author_len = strlen(commit->author);
1039 	size_t committer_len = strlen(commit->committer);
1040 	size_t logmsg_len = strlen(commit->logmsg);
1041 
1042 	total = sizeof(*icommit) + author_len + committer_len +
1043 	    commit->nparents * SHA1_DIGEST_LENGTH;
1044 
1045 	buf = malloc(total);
1046 	if (buf == NULL)
1047 		return got_error_from_errno("malloc");
1048 
1049 	icommit = (struct got_imsg_commit_object *)buf;
1050 	memcpy(icommit->tree_id, commit->tree_id->sha1,
1051 	    sizeof(icommit->tree_id));
1052 	icommit->author_len = author_len;
1053 	icommit->author_time = commit->author_time;
1054 	icommit->author_gmtoff = commit->author_gmtoff;
1055 	icommit->committer_len = committer_len;
1056 	icommit->committer_time = commit->committer_time;
1057 	icommit->committer_gmtoff = commit->committer_gmtoff;
1058 	icommit->logmsg_len = logmsg_len;
1059 	icommit->nparents = commit->nparents;
1060 
1061 	len = sizeof(*icommit);
1062 	memcpy(buf + len, commit->author, author_len);
1063 	len += author_len;
1064 	memcpy(buf + len, commit->committer, committer_len);
1065 	len += committer_len;
1066 	STAILQ_FOREACH(qid, &commit->parent_ids, entry) {
1067 		memcpy(buf + len, qid->id, SHA1_DIGEST_LENGTH);
1068 		len += SHA1_DIGEST_LENGTH;
1069 	}
1070 
1071 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
1072 		err = got_error_from_errno("imsg_compose COMMIT");
1073 		goto done;
1074 	}
1075 
1076 	if (logmsg_len == 0 ||
1077 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1078 		err = flush_imsg(ibuf);
1079 		if (err)
1080 			goto done;
1081 	}
1082 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
1083 done:
1084 	free(buf);
1085 	return err;
1086 }
1087 
1088 static const struct got_error *
1089 get_commit_from_imsg(struct got_commit_object **commit,
1090     struct imsg *imsg, size_t datalen, struct imsgbuf *ibuf)
1091 {
1092 	const struct got_error *err = NULL;
1093 	struct got_imsg_commit_object *icommit;
1094 	size_t len = 0;
1095 	int i;
1096 
1097 	if (datalen < sizeof(*icommit))
1098 		return got_error(GOT_ERR_PRIVSEP_LEN);
1099 
1100 	icommit = imsg->data;
1101 	if (datalen != sizeof(*icommit) + icommit->author_len +
1102 	    icommit->committer_len +
1103 	    icommit->nparents * SHA1_DIGEST_LENGTH)
1104 		return got_error(GOT_ERR_PRIVSEP_LEN);
1105 
1106 	if (icommit->nparents < 0)
1107 		return got_error(GOT_ERR_PRIVSEP_LEN);
1108 
1109 	len += sizeof(*icommit);
1110 
1111 	*commit = got_object_commit_alloc_partial();
1112 	if (*commit == NULL)
1113 		return got_error_from_errno(
1114 		    "got_object_commit_alloc_partial");
1115 
1116 	memcpy((*commit)->tree_id->sha1, icommit->tree_id,
1117 	    SHA1_DIGEST_LENGTH);
1118 	(*commit)->author_time = icommit->author_time;
1119 	(*commit)->author_gmtoff = icommit->author_gmtoff;
1120 	(*commit)->committer_time = icommit->committer_time;
1121 	(*commit)->committer_gmtoff = icommit->committer_gmtoff;
1122 
1123 	if (icommit->author_len == 0) {
1124 		(*commit)->author = strdup("");
1125 		if ((*commit)->author == NULL) {
1126 			err = got_error_from_errno("strdup");
1127 			goto done;
1128 		}
1129 	} else {
1130 		(*commit)->author = malloc(icommit->author_len + 1);
1131 		if ((*commit)->author == NULL) {
1132 			err = got_error_from_errno("malloc");
1133 			goto done;
1134 		}
1135 		memcpy((*commit)->author, imsg->data + len,
1136 		    icommit->author_len);
1137 		(*commit)->author[icommit->author_len] = '\0';
1138 	}
1139 	len += icommit->author_len;
1140 
1141 	if (icommit->committer_len == 0) {
1142 		(*commit)->committer = strdup("");
1143 		if ((*commit)->committer == NULL) {
1144 			err = got_error_from_errno("strdup");
1145 			goto done;
1146 		}
1147 	} else {
1148 		(*commit)->committer =
1149 		    malloc(icommit->committer_len + 1);
1150 		if ((*commit)->committer == NULL) {
1151 			err = got_error_from_errno("malloc");
1152 			goto done;
1153 		}
1154 		memcpy((*commit)->committer, imsg->data + len,
1155 		    icommit->committer_len);
1156 		(*commit)->committer[icommit->committer_len] = '\0';
1157 	}
1158 	len += icommit->committer_len;
1159 
1160 	if (icommit->logmsg_len == 0) {
1161 		(*commit)->logmsg = strdup("");
1162 		if ((*commit)->logmsg == NULL) {
1163 			err = got_error_from_errno("strdup");
1164 			goto done;
1165 		}
1166 	} else {
1167 		size_t offset = 0, remain = icommit->logmsg_len;
1168 
1169 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1170 		if ((*commit)->logmsg == NULL) {
1171 			err = got_error_from_errno("malloc");
1172 			goto done;
1173 		}
1174 		while (remain > 0) {
1175 			struct imsg imsg_log;
1176 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1177 			    remain);
1178 
1179 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1180 			if (err)
1181 				goto done;
1182 
1183 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1184 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1185 				goto done;
1186 			}
1187 
1188 			memcpy((*commit)->logmsg + offset,
1189 			    imsg_log.data, n);
1190 			imsg_free(&imsg_log);
1191 			offset += n;
1192 			remain -= n;
1193 		}
1194 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1195 	}
1196 
1197 	for (i = 0; i < icommit->nparents; i++) {
1198 		struct got_object_qid *qid;
1199 
1200 		err = got_object_qid_alloc_partial(&qid);
1201 		if (err)
1202 			break;
1203 		memcpy(qid->id, imsg->data + len +
1204 		    i * SHA1_DIGEST_LENGTH, sizeof(*qid->id));
1205 		STAILQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1206 		(*commit)->nparents++;
1207 	}
1208 done:
1209 	if (err) {
1210 		got_object_commit_close(*commit);
1211 		*commit = NULL;
1212 	}
1213 	return err;
1214 }
1215 
1216 const struct got_error *
1217 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1218 {
1219 	const struct got_error *err = NULL;
1220 	struct imsg imsg;
1221 	size_t datalen;
1222 	const size_t min_datalen =
1223 	    MIN(sizeof(struct got_imsg_error),
1224 	    sizeof(struct got_imsg_commit_object));
1225 
1226 	*commit = NULL;
1227 
1228 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1229 	if (err)
1230 		return err;
1231 
1232 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1233 
1234 	switch (imsg.hdr.type) {
1235 	case GOT_IMSG_COMMIT:
1236 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1237 		break;
1238 	default:
1239 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1240 		break;
1241 	}
1242 
1243 	imsg_free(&imsg);
1244 
1245 	return err;
1246 }
1247 
1248 const struct got_error *
1249 got_privsep_send_tree(struct imsgbuf *ibuf, struct got_pathlist_head *entries,
1250     int nentries)
1251 {
1252 	const struct got_error *err = NULL;
1253 	struct got_imsg_tree_object itree;
1254 	struct got_pathlist_entry *pe;
1255 	size_t totlen;
1256 	int nimsg; /* number of imsg queued in ibuf */
1257 
1258 	itree.nentries = nentries;
1259 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1260 	    == -1)
1261 		return got_error_from_errno("imsg_compose TREE");
1262 
1263 	totlen = sizeof(itree);
1264 	nimsg = 1;
1265 	TAILQ_FOREACH(pe, entries, entry) {
1266 		const char *name = pe->path;
1267 		struct got_parsed_tree_entry *pte = pe->data;
1268 		struct ibuf *wbuf;
1269 		size_t namelen = strlen(name);
1270 		size_t len = sizeof(struct got_imsg_tree_entry) + namelen;
1271 
1272 		if (len > MAX_IMSGSIZE)
1273 			return got_error(GOT_ERR_NO_SPACE);
1274 
1275 		nimsg++;
1276 		if (totlen + len >= MAX_IMSGSIZE - (IMSG_HEADER_SIZE * nimsg)) {
1277 			err = flush_imsg(ibuf);
1278 			if (err)
1279 				return err;
1280 			nimsg = 0;
1281 		}
1282 
1283 		wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRY, 0, 0, len);
1284 		if (wbuf == NULL)
1285 			return got_error_from_errno("imsg_create TREE_ENTRY");
1286 
1287 		/* Keep in sync with struct got_imsg_tree_object definition! */
1288 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1) {
1289 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1290 			ibuf_free(wbuf);
1291 			return err;
1292 		}
1293 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1) {
1294 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1295 			ibuf_free(wbuf);
1296 			return err;
1297 		}
1298 
1299 		if (imsg_add(wbuf, name, namelen) == -1) {
1300 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1301 			ibuf_free(wbuf);
1302 			return err;
1303 		}
1304 
1305 		wbuf->fd = -1;
1306 		imsg_close(ibuf, wbuf);
1307 
1308 		totlen += len;
1309 	}
1310 
1311 	return flush_imsg(ibuf);
1312 }
1313 
1314 const struct got_error *
1315 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1316 {
1317 	const struct got_error *err = NULL;
1318 	const size_t min_datalen =
1319 	    MIN(sizeof(struct got_imsg_error),
1320 	    sizeof(struct got_imsg_tree_object));
1321 	struct got_imsg_tree_object *itree;
1322 	int nentries = 0;
1323 
1324 	*tree = NULL;
1325 get_more:
1326 	err = read_imsg(ibuf);
1327 	if (err)
1328 		goto done;
1329 
1330 	for (;;) {
1331 		struct imsg imsg;
1332 		size_t n;
1333 		size_t datalen;
1334 		struct got_imsg_tree_entry *ite;
1335 		struct got_tree_entry *te = NULL;
1336 
1337 		n = imsg_get(ibuf, &imsg);
1338 		if (n == 0) {
1339 			if (*tree && (*tree)->nentries != nentries)
1340 				goto get_more;
1341 			break;
1342 		}
1343 
1344 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen) {
1345 			imsg_free(&imsg);
1346 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1347 			break;
1348 		}
1349 
1350 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1351 
1352 		switch (imsg.hdr.type) {
1353 		case GOT_IMSG_ERROR:
1354 			err = recv_imsg_error(&imsg, datalen);
1355 			break;
1356 		case GOT_IMSG_TREE:
1357 			/* This message should only appear once. */
1358 			if (*tree != NULL) {
1359 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1360 				break;
1361 			}
1362 			if (datalen != sizeof(*itree)) {
1363 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1364 				break;
1365 			}
1366 			itree = imsg.data;
1367 			*tree = malloc(sizeof(**tree));
1368 			if (*tree == NULL) {
1369 				err = got_error_from_errno("malloc");
1370 				break;
1371 			}
1372 			(*tree)->entries = calloc(itree->nentries,
1373 			    sizeof(struct got_tree_entry));
1374 			if ((*tree)->entries == NULL) {
1375 				err = got_error_from_errno("malloc");
1376 				break;
1377 			}
1378 			(*tree)->nentries = itree->nentries;
1379 			(*tree)->refcnt = 0;
1380 			break;
1381 		case GOT_IMSG_TREE_ENTRY:
1382 			/* This message should be preceeded by GOT_IMSG_TREE. */
1383 			if (*tree == NULL) {
1384 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1385 				break;
1386 			}
1387 			if (datalen < sizeof(*ite) || datalen > MAX_IMSGSIZE) {
1388 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1389 				break;
1390 			}
1391 
1392 			/* Remaining data contains the entry's name. */
1393 			datalen -= sizeof(*ite);
1394 			if (datalen == 0 || datalen > MAX_IMSGSIZE) {
1395 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1396 				break;
1397 			}
1398 			ite = imsg.data;
1399 
1400 			if (datalen + 1 > sizeof(te->name)) {
1401 				err = got_error(GOT_ERR_NO_SPACE);
1402 				break;
1403 			}
1404 			te = &(*tree)->entries[nentries];
1405 			memcpy(te->name, imsg.data + sizeof(*ite), datalen);
1406 			te->name[datalen] = '\0';
1407 
1408 			memcpy(te->id.sha1, ite->id, SHA1_DIGEST_LENGTH);
1409 			te->mode = ite->mode;
1410 			te->idx = nentries;
1411 			nentries++;
1412 			break;
1413 		default:
1414 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1415 			break;
1416 		}
1417 
1418 		imsg_free(&imsg);
1419 		if (err)
1420 			break;
1421 	}
1422 done:
1423 	if (*tree && (*tree)->nentries != nentries) {
1424 		if (err == NULL)
1425 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1426 		got_object_tree_close(*tree);
1427 		*tree = NULL;
1428 	}
1429 
1430 	return err;
1431 }
1432 
1433 const struct got_error *
1434 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1435     const uint8_t *data)
1436 {
1437 	struct got_imsg_blob iblob;
1438 
1439 	iblob.size = size;
1440 	iblob.hdrlen = hdrlen;
1441 
1442 	if (data) {
1443 		uint8_t *buf;
1444 
1445 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1446 			return got_error(GOT_ERR_NO_SPACE);
1447 
1448 		buf = malloc(sizeof(iblob) + size);
1449 		if (buf == NULL)
1450 			return got_error_from_errno("malloc");
1451 
1452 		memcpy(buf, &iblob, sizeof(iblob));
1453 		memcpy(buf + sizeof(iblob), data, size);
1454 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1455 		    sizeof(iblob) + size) == -1) {
1456 			free(buf);
1457 			return got_error_from_errno("imsg_compose BLOB");
1458 		}
1459 		free(buf);
1460 	} else {
1461 		/* Data has already been written to file descriptor. */
1462 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1463 		    sizeof(iblob)) == -1)
1464 			return got_error_from_errno("imsg_compose BLOB");
1465 	}
1466 
1467 
1468 	return flush_imsg(ibuf);
1469 }
1470 
1471 const struct got_error *
1472 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1473     struct imsgbuf *ibuf)
1474 {
1475 	const struct got_error *err = NULL;
1476 	struct imsg imsg;
1477 	struct got_imsg_blob *iblob;
1478 	size_t datalen;
1479 
1480 	*outbuf = NULL;
1481 
1482 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1483 	if (err)
1484 		return err;
1485 
1486 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1487 
1488 	switch (imsg.hdr.type) {
1489 	case GOT_IMSG_BLOB:
1490 		if (datalen < sizeof(*iblob)) {
1491 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1492 			break;
1493 		}
1494 		iblob = imsg.data;
1495 		*size = iblob->size;
1496 		*hdrlen = iblob->hdrlen;
1497 
1498 		if (datalen == sizeof(*iblob)) {
1499 			/* Data has been written to file descriptor. */
1500 			break;
1501 		}
1502 
1503 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX) {
1504 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1505 			break;
1506 		}
1507 
1508 		*outbuf = malloc(*size);
1509 		if (*outbuf == NULL) {
1510 			err = got_error_from_errno("malloc");
1511 			break;
1512 		}
1513 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1514 		break;
1515 	default:
1516 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1517 		break;
1518 	}
1519 
1520 	imsg_free(&imsg);
1521 
1522 	return err;
1523 }
1524 
1525 static const struct got_error *
1526 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1527 {
1528 	const struct got_error *err = NULL;
1529 	size_t offset, remain;
1530 
1531 	offset = 0;
1532 	remain = tagmsg_len;
1533 	while (remain > 0) {
1534 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1535 
1536 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1537 		    tag->tagmsg + offset, n) == -1) {
1538 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1539 			break;
1540 		}
1541 
1542 		err = flush_imsg(ibuf);
1543 		if (err)
1544 			break;
1545 
1546 		offset += n;
1547 		remain -= n;
1548 	}
1549 
1550 	return err;
1551 }
1552 
1553 const struct got_error *
1554 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1555 {
1556 	const struct got_error *err = NULL;
1557 	struct got_imsg_tag_object *itag;
1558 	uint8_t *buf;
1559 	size_t len, total;
1560 	size_t tag_len = strlen(tag->tag);
1561 	size_t tagger_len = strlen(tag->tagger);
1562 	size_t tagmsg_len = strlen(tag->tagmsg);
1563 
1564 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1565 
1566 	buf = malloc(total);
1567 	if (buf == NULL)
1568 		return got_error_from_errno("malloc");
1569 
1570 	itag = (struct got_imsg_tag_object *)buf;
1571 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1572 	itag->obj_type = tag->obj_type;
1573 	itag->tag_len = tag_len;
1574 	itag->tagger_len = tagger_len;
1575 	itag->tagger_time = tag->tagger_time;
1576 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1577 	itag->tagmsg_len = tagmsg_len;
1578 
1579 	len = sizeof(*itag);
1580 	memcpy(buf + len, tag->tag, tag_len);
1581 	len += tag_len;
1582 	memcpy(buf + len, tag->tagger, tagger_len);
1583 	len += tagger_len;
1584 
1585 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1586 		err = got_error_from_errno("imsg_compose TAG");
1587 		goto done;
1588 	}
1589 
1590 	if (tagmsg_len == 0 ||
1591 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1592 		err = flush_imsg(ibuf);
1593 		if (err)
1594 			goto done;
1595 	}
1596 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1597 done:
1598 	free(buf);
1599 	return err;
1600 }
1601 
1602 const struct got_error *
1603 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1604 {
1605 	const struct got_error *err = NULL;
1606 	struct imsg imsg;
1607 	struct got_imsg_tag_object *itag;
1608 	size_t len, datalen;
1609 	const size_t min_datalen =
1610 	    MIN(sizeof(struct got_imsg_error),
1611 	    sizeof(struct got_imsg_tag_object));
1612 
1613 	*tag = NULL;
1614 
1615 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1616 	if (err)
1617 		return err;
1618 
1619 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1620 	len = 0;
1621 
1622 	switch (imsg.hdr.type) {
1623 	case GOT_IMSG_TAG:
1624 		if (datalen < sizeof(*itag)) {
1625 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1626 			break;
1627 		}
1628 		itag = imsg.data;
1629 		if (datalen != sizeof(*itag) + itag->tag_len +
1630 		    itag->tagger_len) {
1631 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1632 			break;
1633 		}
1634 		len += sizeof(*itag);
1635 
1636 		*tag = calloc(1, sizeof(**tag));
1637 		if (*tag == NULL) {
1638 			err = got_error_from_errno("calloc");
1639 			break;
1640 		}
1641 
1642 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1643 
1644 		if (itag->tag_len == 0) {
1645 			(*tag)->tag = strdup("");
1646 			if ((*tag)->tag == NULL) {
1647 				err = got_error_from_errno("strdup");
1648 				break;
1649 			}
1650 		} else {
1651 			(*tag)->tag = malloc(itag->tag_len + 1);
1652 			if ((*tag)->tag == NULL) {
1653 				err = got_error_from_errno("malloc");
1654 				break;
1655 			}
1656 			memcpy((*tag)->tag, imsg.data + len,
1657 			    itag->tag_len);
1658 			(*tag)->tag[itag->tag_len] = '\0';
1659 		}
1660 		len += itag->tag_len;
1661 
1662 		(*tag)->obj_type = itag->obj_type;
1663 		(*tag)->tagger_time = itag->tagger_time;
1664 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1665 
1666 		if (itag->tagger_len == 0) {
1667 			(*tag)->tagger = strdup("");
1668 			if ((*tag)->tagger == NULL) {
1669 				err = got_error_from_errno("strdup");
1670 				break;
1671 			}
1672 		} else {
1673 			(*tag)->tagger = malloc(itag->tagger_len + 1);
1674 			if ((*tag)->tagger == NULL) {
1675 				err = got_error_from_errno("malloc");
1676 				break;
1677 			}
1678 			memcpy((*tag)->tagger, imsg.data + len,
1679 			    itag->tagger_len);
1680 			(*tag)->tagger[itag->tagger_len] = '\0';
1681 		}
1682 		len += itag->tagger_len;
1683 
1684 		if (itag->tagmsg_len == 0) {
1685 			(*tag)->tagmsg = strdup("");
1686 			if ((*tag)->tagmsg == NULL) {
1687 				err = got_error_from_errno("strdup");
1688 				break;
1689 			}
1690 		} else {
1691 			size_t offset = 0, remain = itag->tagmsg_len;
1692 
1693 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1694 			if ((*tag)->tagmsg == NULL) {
1695 				err = got_error_from_errno("malloc");
1696 				break;
1697 			}
1698 			while (remain > 0) {
1699 				struct imsg imsg_log;
1700 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1701 				    remain);
1702 
1703 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1704 				if (err)
1705 					return err;
1706 
1707 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1708 					return got_error(GOT_ERR_PRIVSEP_MSG);
1709 
1710 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1711 				    n);
1712 				imsg_free(&imsg_log);
1713 				offset += n;
1714 				remain -= n;
1715 			}
1716 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1717 		}
1718 
1719 		break;
1720 	default:
1721 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1722 		break;
1723 	}
1724 
1725 	imsg_free(&imsg);
1726 
1727 	return err;
1728 }
1729 
1730 const struct got_error *
1731 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1732     struct got_packidx *packidx)
1733 {
1734 	const struct got_error *err = NULL;
1735 	struct got_imsg_packidx ipackidx;
1736 	struct got_imsg_pack ipack;
1737 	int fd;
1738 
1739 	ipackidx.len = packidx->len;
1740 	fd = dup(packidx->fd);
1741 	if (fd == -1)
1742 		return got_error_from_errno("dup");
1743 
1744 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
1745 	    sizeof(ipackidx)) == -1) {
1746 		err = got_error_from_errno("imsg_compose PACKIDX");
1747 		close(fd);
1748 		return err;
1749 	}
1750 
1751 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
1752 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
1753 		return got_error(GOT_ERR_NO_SPACE);
1754 	ipack.filesize = pack->filesize;
1755 
1756 	fd = dup(pack->fd);
1757 	if (fd == -1)
1758 		return got_error_from_errno("dup");
1759 
1760 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
1761 	    == -1) {
1762 		err = got_error_from_errno("imsg_compose PACK");
1763 		close(fd);
1764 		return err;
1765 	}
1766 
1767 	return flush_imsg(ibuf);
1768 }
1769 
1770 const struct got_error *
1771 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
1772     struct got_object_id *id)
1773 {
1774 	struct got_imsg_packed_object iobj;
1775 
1776 	iobj.idx = idx;
1777 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
1778 
1779 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
1780 	    &iobj, sizeof(iobj)) == -1)
1781 		return got_error_from_errno("imsg_compose "
1782 		    "PACKED_OBJECT_REQUEST");
1783 
1784 	return flush_imsg(ibuf);
1785 }
1786 
1787 const struct got_error *
1788 got_privsep_send_packed_raw_obj_req(struct imsgbuf *ibuf, int idx,
1789     struct got_object_id *id)
1790 {
1791 	struct got_imsg_packed_object iobj;
1792 
1793 	iobj.idx = idx;
1794 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
1795 
1796 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_RAW_OBJECT_REQUEST, 0, 0, -1,
1797 	    &iobj, sizeof(iobj)) == -1)
1798 		return got_error_from_errno("imsg_compose "
1799 		    "PACKED_OBJECT_REQUEST");
1800 
1801 	return flush_imsg(ibuf);
1802 }
1803 
1804 const struct got_error *
1805 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
1806 {
1807 	const struct got_error *err = NULL;
1808 
1809 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
1810 	    NULL, 0) == -1) {
1811 		err = got_error_from_errno("imsg_compose "
1812 		    "GITCONFIG_PARSE_REQUEST");
1813 		close(fd);
1814 		return err;
1815 	}
1816 
1817 	return flush_imsg(ibuf);
1818 }
1819 
1820 const struct got_error *
1821 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
1822 {
1823 	if (imsg_compose(ibuf,
1824 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
1825 	    NULL, 0) == -1)
1826 		return got_error_from_errno("imsg_compose "
1827 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
1828 
1829 	return flush_imsg(ibuf);
1830 }
1831 
1832 const struct got_error *
1833 got_privsep_send_gitconfig_repository_extensions_req(struct imsgbuf *ibuf)
1834 {
1835 	if (imsg_compose(ibuf,
1836 	    GOT_IMSG_GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST, 0, 0, -1,
1837 	    NULL, 0) == -1)
1838 		return got_error_from_errno("imsg_compose "
1839 		    "GITCONFIG_REPOSITORY_EXTENSIONS_REQUEST");
1840 
1841 	return flush_imsg(ibuf);
1842 }
1843 
1844 
1845 const struct got_error *
1846 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
1847 {
1848 	if (imsg_compose(ibuf,
1849 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
1850 		return got_error_from_errno("imsg_compose "
1851 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
1852 
1853 	return flush_imsg(ibuf);
1854 }
1855 
1856 const struct got_error *
1857 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
1858 {
1859 	if (imsg_compose(ibuf,
1860 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
1861 		return got_error_from_errno("imsg_compose "
1862 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
1863 
1864 	return flush_imsg(ibuf);
1865 }
1866 
1867 const struct got_error *
1868 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
1869 {
1870 	if (imsg_compose(ibuf,
1871 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
1872 		return got_error_from_errno("imsg_compose "
1873 		    "GITCONFIG_REMOTE_REQUEST");
1874 
1875 	return flush_imsg(ibuf);
1876 }
1877 
1878 const struct got_error *
1879 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
1880 {
1881 	if (imsg_compose(ibuf,
1882 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
1883 		return got_error_from_errno("imsg_compose "
1884 		    "GITCONFIG_OWNER_REQUEST");
1885 
1886 	return flush_imsg(ibuf);
1887 }
1888 
1889 const struct got_error *
1890 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
1891 {
1892 	const struct got_error *err = NULL;
1893 	struct imsg imsg;
1894 	size_t datalen;
1895 	const size_t min_datalen = 0;
1896 
1897 	*str = NULL;
1898 
1899 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1900 	if (err)
1901 		return err;
1902 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1903 
1904 	switch (imsg.hdr.type) {
1905 	case GOT_IMSG_GITCONFIG_STR_VAL:
1906 		if (datalen == 0)
1907 			break;
1908 		/* datalen does not include terminating \0 */
1909 		*str = malloc(datalen + 1);
1910 		if (*str == NULL) {
1911 			err = got_error_from_errno("malloc");
1912 			break;
1913 		}
1914 		memcpy(*str, imsg.data, datalen);
1915 		(*str)[datalen] = '\0';
1916 		break;
1917 	default:
1918 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1919 		break;
1920 	}
1921 
1922 	imsg_free(&imsg);
1923 	return err;
1924 }
1925 
1926 const struct got_error *
1927 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
1928 {
1929 	const struct got_error *err = NULL;
1930 	struct imsg imsg;
1931 	size_t datalen;
1932 	const size_t min_datalen =
1933 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
1934 
1935 	*val = 0;
1936 
1937 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1938 	if (err)
1939 		return err;
1940 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1941 
1942 	switch (imsg.hdr.type) {
1943 	case GOT_IMSG_GITCONFIG_INT_VAL:
1944 		if (datalen != sizeof(*val)) {
1945 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1946 			break;
1947 		}
1948 		memcpy(val, imsg.data, sizeof(*val));
1949 		break;
1950 	default:
1951 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1952 		break;
1953 	}
1954 
1955 	imsg_free(&imsg);
1956 	return err;
1957 }
1958 
1959 static void
1960 free_remote_data(struct got_remote_repo *remote)
1961 {
1962 	int i;
1963 
1964 	free(remote->name);
1965 	free(remote->url);
1966 	for (i = 0; i < remote->nbranches; i++)
1967 		free(remote->branches[i]);
1968 	free(remote->branches);
1969 	for (i = 0; i < remote->nrefs; i++)
1970 		free(remote->refs[i]);
1971 	free(remote->refs);
1972 }
1973 
1974 const struct got_error *
1975 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
1976     int *nremotes, struct imsgbuf *ibuf)
1977 {
1978 	const struct got_error *err = NULL;
1979 	struct imsg imsg;
1980 	size_t datalen;
1981 	struct got_imsg_remotes iremotes;
1982 	struct got_imsg_remote iremote;
1983 
1984 	*remotes = NULL;
1985 	*nremotes = 0;
1986 	iremotes.nremotes = 0;
1987 
1988 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
1989 	if (err)
1990 		return err;
1991 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1992 
1993 	switch (imsg.hdr.type) {
1994 	case GOT_IMSG_GITCONFIG_REMOTES:
1995 		if (datalen != sizeof(iremotes)) {
1996 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1997 			break;
1998 		}
1999 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2000 		if (iremotes.nremotes == 0) {
2001 			imsg_free(&imsg);
2002 			return NULL;
2003 		}
2004 		break;
2005 	default:
2006 		imsg_free(&imsg);
2007 		return got_error(GOT_ERR_PRIVSEP_MSG);
2008 	}
2009 
2010 	imsg_free(&imsg);
2011 
2012 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2013 	if (*remotes == NULL)
2014 		return got_error_from_errno("recallocarray");
2015 
2016 	while (*nremotes < iremotes.nremotes) {
2017 		struct got_remote_repo *remote;
2018 
2019 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
2020 		if (err)
2021 			break;
2022 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2023 
2024 		switch (imsg.hdr.type) {
2025 		case GOT_IMSG_GITCONFIG_REMOTE:
2026 			remote = &(*remotes)[*nremotes];
2027 			memset(remote, 0, sizeof(*remote));
2028 			if (datalen < sizeof(iremote)) {
2029 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2030 				break;
2031 			}
2032 			memcpy(&iremote, imsg.data, sizeof(iremote));
2033 			if (iremote.name_len == 0 || iremote.url_len == 0 ||
2034 			    (sizeof(iremote) + iremote.name_len +
2035 			    iremote.url_len) > datalen) {
2036 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2037 				break;
2038 			}
2039 			remote->name = strndup(imsg.data + sizeof(iremote),
2040 			    iremote.name_len);
2041 			if (remote->name == NULL) {
2042 				err = got_error_from_errno("strndup");
2043 				break;
2044 			}
2045 			remote->url = strndup(imsg.data + sizeof(iremote) +
2046 			    iremote.name_len, iremote.url_len);
2047 			if (remote->url == NULL) {
2048 				err = got_error_from_errno("strndup");
2049 				free_remote_data(remote);
2050 				break;
2051 			}
2052 			remote->mirror_references = iremote.mirror_references;
2053 			remote->fetch_all_branches = iremote.fetch_all_branches;
2054 			remote->nbranches = 0;
2055 			remote->branches = NULL;
2056 			remote->nrefs = 0;
2057 			remote->refs = NULL;
2058 			(*nremotes)++;
2059 			break;
2060 		default:
2061 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2062 			break;
2063 		}
2064 
2065 		imsg_free(&imsg);
2066 		if (err)
2067 			break;
2068 	}
2069 
2070 	if (err) {
2071 		int i;
2072 		for (i = 0; i < *nremotes; i++)
2073 			free_remote_data(&(*remotes)[i]);
2074 		free(*remotes);
2075 		*remotes = NULL;
2076 		*nremotes = 0;
2077 	}
2078 	return err;
2079 }
2080 
2081 const struct got_error *
2082 got_privsep_send_gotconfig_parse_req(struct imsgbuf *ibuf, int fd)
2083 {
2084 	const struct got_error *err = NULL;
2085 
2086 	if (imsg_compose(ibuf, GOT_IMSG_GOTCONFIG_PARSE_REQUEST, 0, 0, fd,
2087 	    NULL, 0) == -1) {
2088 		err = got_error_from_errno("imsg_compose "
2089 		    "GOTCONFIG_PARSE_REQUEST");
2090 		close(fd);
2091 		return err;
2092 	}
2093 
2094 	return flush_imsg(ibuf);
2095 }
2096 
2097 const struct got_error *
2098 got_privsep_send_gotconfig_author_req(struct imsgbuf *ibuf)
2099 {
2100 	if (imsg_compose(ibuf,
2101 	    GOT_IMSG_GOTCONFIG_AUTHOR_REQUEST, 0, 0, -1, NULL, 0) == -1)
2102 		return got_error_from_errno("imsg_compose "
2103 		    "GOTCONFIG_AUTHOR_REQUEST");
2104 
2105 	return flush_imsg(ibuf);
2106 }
2107 
2108 const struct got_error *
2109 got_privsep_send_gotconfig_remotes_req(struct imsgbuf *ibuf)
2110 {
2111 	if (imsg_compose(ibuf,
2112 	    GOT_IMSG_GOTCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
2113 		return got_error_from_errno("imsg_compose "
2114 		    "GOTCONFIG_REMOTE_REQUEST");
2115 
2116 	return flush_imsg(ibuf);
2117 }
2118 
2119 const struct got_error *
2120 got_privsep_recv_gotconfig_str(char **str, struct imsgbuf *ibuf)
2121 {
2122 	const struct got_error *err = NULL;
2123 	struct imsg imsg;
2124 	size_t datalen;
2125 	const size_t min_datalen = 0;
2126 
2127 	*str = NULL;
2128 
2129 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2130 	if (err)
2131 		return err;
2132 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2133 
2134 	switch (imsg.hdr.type) {
2135 	case GOT_IMSG_ERROR:
2136 		if (datalen < sizeof(struct got_imsg_error)) {
2137 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2138 			break;
2139 		}
2140 		err = recv_imsg_error(&imsg, datalen);
2141 		break;
2142 	case GOT_IMSG_GOTCONFIG_STR_VAL:
2143 		if (datalen == 0)
2144 			break;
2145 		/* datalen does not include terminating \0 */
2146 		*str = malloc(datalen + 1);
2147 		if (*str == NULL) {
2148 			err = got_error_from_errno("malloc");
2149 			break;
2150 		}
2151 		memcpy(*str, imsg.data, datalen);
2152 		(*str)[datalen] = '\0';
2153 		break;
2154 	default:
2155 		err = got_error(GOT_ERR_PRIVSEP_MSG);
2156 		break;
2157 	}
2158 
2159 	imsg_free(&imsg);
2160 	return err;
2161 }
2162 
2163 
2164 const struct got_error *
2165 got_privsep_recv_gotconfig_remotes(struct got_remote_repo **remotes,
2166     int *nremotes, struct imsgbuf *ibuf)
2167 {
2168 	const struct got_error *err = NULL;
2169 	struct imsg imsg;
2170 	size_t datalen;
2171 	struct got_imsg_remotes iremotes;
2172 	struct got_imsg_remote iremote;
2173 	const size_t min_datalen =
2174 	    MIN(sizeof(struct got_imsg_error), sizeof(iremotes));
2175 
2176 	*remotes = NULL;
2177 	*nremotes = 0;
2178 	iremotes.nremotes = 0;
2179 
2180 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2181 	if (err)
2182 		return err;
2183 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2184 
2185 	switch (imsg.hdr.type) {
2186 	case GOT_IMSG_ERROR:
2187 		if (datalen < sizeof(struct got_imsg_error)) {
2188 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2189 			break;
2190 		}
2191 		err = recv_imsg_error(&imsg, datalen);
2192 		break;
2193 	case GOT_IMSG_GOTCONFIG_REMOTES:
2194 		if (datalen != sizeof(iremotes)) {
2195 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2196 			break;
2197 		}
2198 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2199 		if (iremotes.nremotes == 0) {
2200 			imsg_free(&imsg);
2201 			return NULL;
2202 		}
2203 		break;
2204 	default:
2205 		imsg_free(&imsg);
2206 		return got_error(GOT_ERR_PRIVSEP_MSG);
2207 	}
2208 
2209 	imsg_free(&imsg);
2210 
2211 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2212 	if (*remotes == NULL)
2213 		return got_error_from_errno("recallocarray");
2214 
2215 	while (*nremotes < iremotes.nremotes) {
2216 		struct got_remote_repo *remote;
2217 		const size_t min_datalen =
2218 		    MIN(sizeof(struct got_imsg_error), sizeof(iremote));
2219 		int i;
2220 
2221 		err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
2222 		if (err)
2223 			break;
2224 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2225 
2226 		switch (imsg.hdr.type) {
2227 		case GOT_IMSG_ERROR:
2228 			if (datalen < sizeof(struct got_imsg_error)) {
2229 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2230 				break;
2231 			}
2232 			err = recv_imsg_error(&imsg, datalen);
2233 			break;
2234 		case GOT_IMSG_GOTCONFIG_REMOTE:
2235 			remote = &(*remotes)[*nremotes];
2236 			memset(remote, 0, sizeof(*remote));
2237 			if (datalen < sizeof(iremote)) {
2238 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2239 				break;
2240 			}
2241 			memcpy(&iremote, imsg.data, sizeof(iremote));
2242 			if (iremote.name_len == 0 || iremote.url_len == 0 ||
2243 			    (sizeof(iremote) + iremote.name_len +
2244 			    iremote.url_len) > datalen) {
2245 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2246 				break;
2247 			}
2248 			remote->name = strndup(imsg.data + sizeof(iremote),
2249 			    iremote.name_len);
2250 			if (remote->name == NULL) {
2251 				err = got_error_from_errno("strndup");
2252 				break;
2253 			}
2254 			remote->url = strndup(imsg.data + sizeof(iremote) +
2255 			    iremote.name_len, iremote.url_len);
2256 			if (remote->url == NULL) {
2257 				err = got_error_from_errno("strndup");
2258 				free_remote_data(remote);
2259 				break;
2260 			}
2261 			remote->mirror_references = iremote.mirror_references;
2262 			remote->fetch_all_branches = iremote.fetch_all_branches;
2263 			if (iremote.nbranches > 0) {
2264 				remote->branches = recallocarray(NULL, 0,
2265 				    iremote.nbranches, sizeof(char *));
2266 				if (remote->branches == NULL) {
2267 					err = got_error_from_errno("calloc");
2268 					free_remote_data(remote);
2269 					break;
2270 				}
2271 			}
2272 			remote->nbranches = 0;
2273 			for (i = 0; i < iremote.nbranches; i++) {
2274 				char *branch;
2275 				err = got_privsep_recv_gotconfig_str(&branch,
2276 				    ibuf);
2277 				if (err) {
2278 					free_remote_data(remote);
2279 					goto done;
2280 				}
2281 				remote->branches[i] = branch;
2282 				remote->nbranches++;
2283 			}
2284 			if (iremote.nrefs > 0) {
2285 				remote->refs = recallocarray(NULL, 0,
2286 				    iremote.nrefs, sizeof(char *));
2287 				if (remote->refs == NULL) {
2288 					err = got_error_from_errno("calloc");
2289 					free_remote_data(remote);
2290 					break;
2291 				}
2292 			}
2293 			remote->nrefs = 0;
2294 			for (i = 0; i < iremote.nrefs; i++) {
2295 				char *ref;
2296 				err = got_privsep_recv_gotconfig_str(&ref,
2297 				    ibuf);
2298 				if (err) {
2299 					free_remote_data(remote);
2300 					goto done;
2301 				}
2302 				remote->refs[i] = ref;
2303 				remote->nrefs++;
2304 			}
2305 			(*nremotes)++;
2306 			break;
2307 		default:
2308 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2309 			break;
2310 		}
2311 
2312 		imsg_free(&imsg);
2313 		if (err)
2314 			break;
2315 	}
2316 done:
2317 	if (err) {
2318 		int i;
2319 		for (i = 0; i < *nremotes; i++)
2320 			free_remote_data(&(*remotes)[i]);
2321 		free(*remotes);
2322 		*remotes = NULL;
2323 		*nremotes = 0;
2324 	}
2325 	return err;
2326 }
2327 
2328 const struct got_error *
2329 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
2330      struct got_object_id *id, int idx, const char *path)
2331 {
2332 	const struct got_error *err = NULL;
2333 	struct ibuf *wbuf;
2334 	size_t path_len = strlen(path) + 1;
2335 
2336 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
2337 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
2338 	if (wbuf == NULL)
2339 		return got_error_from_errno(
2340 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
2341 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
2342 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2343 		ibuf_free(wbuf);
2344 		return err;
2345 	}
2346 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1) {
2347 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2348 		ibuf_free(wbuf);
2349 		return err;
2350 	}
2351 	if (imsg_add(wbuf, path, path_len) == -1) {
2352 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2353 		ibuf_free(wbuf);
2354 		return err;
2355 	}
2356 
2357 	wbuf->fd = -1;
2358 	imsg_close(ibuf, wbuf);
2359 
2360 	return flush_imsg(ibuf);
2361 }
2362 
2363 const struct got_error *
2364 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
2365     struct got_object_id **changed_commit_id,
2366     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
2367 {
2368 	const struct got_error *err = NULL;
2369 	struct imsg imsg;
2370 	struct got_imsg_traversed_commits *icommits;
2371 	size_t datalen;
2372 	int i, done = 0;
2373 
2374 	*changed_commit = NULL;
2375 	*changed_commit_id = NULL;
2376 
2377 	while (!done) {
2378 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2379 		if (err)
2380 			return err;
2381 
2382 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2383 		switch (imsg.hdr.type) {
2384 		case GOT_IMSG_TRAVERSED_COMMITS:
2385 			icommits = imsg.data;
2386 			if (datalen != sizeof(*icommits) +
2387 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
2388 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2389 				break;
2390 			}
2391 			for (i = 0; i < icommits->ncommits; i++) {
2392 				struct got_object_qid *qid;
2393 				uint8_t *sha1 = (uint8_t *)imsg.data +
2394 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
2395 				err = got_object_qid_alloc_partial(&qid);
2396 				if (err)
2397 					break;
2398 				memcpy(qid->id->sha1, sha1, SHA1_DIGEST_LENGTH);
2399 				STAILQ_INSERT_TAIL(commit_ids, qid, entry);
2400 
2401 				/* The last commit may contain a change. */
2402 				if (i == icommits->ncommits - 1) {
2403 					*changed_commit_id =
2404 					    got_object_id_dup(qid->id);
2405 					if (*changed_commit_id == NULL) {
2406 						err = got_error_from_errno(
2407 						    "got_object_id_dup");
2408 						break;
2409 					}
2410 				}
2411 			}
2412 			break;
2413 		case GOT_IMSG_COMMIT:
2414 			if (*changed_commit_id == NULL) {
2415 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2416 				break;
2417 			}
2418 			err = get_commit_from_imsg(changed_commit, &imsg,
2419 			    datalen, ibuf);
2420 			break;
2421 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
2422 			done = 1;
2423 			break;
2424 		default:
2425 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2426 			break;
2427 		}
2428 
2429 		imsg_free(&imsg);
2430 		if (err)
2431 			break;
2432 	}
2433 
2434 	if (err)
2435 		got_object_id_queue_free(commit_ids);
2436 	return err;
2437 }
2438 
2439 const struct got_error *
2440 got_privsep_unveil_exec_helpers(void)
2441 {
2442 	const char *helpers[] = {
2443 	    GOT_PATH_PROG_READ_PACK,
2444 	    GOT_PATH_PROG_READ_OBJECT,
2445 	    GOT_PATH_PROG_READ_COMMIT,
2446 	    GOT_PATH_PROG_READ_TREE,
2447 	    GOT_PATH_PROG_READ_BLOB,
2448 	    GOT_PATH_PROG_READ_TAG,
2449 	    GOT_PATH_PROG_READ_GITCONFIG,
2450 	    GOT_PATH_PROG_READ_GOTCONFIG,
2451 	    GOT_PATH_PROG_FETCH_PACK,
2452 	    GOT_PATH_PROG_INDEX_PACK,
2453 	};
2454 	size_t i;
2455 
2456 	for (i = 0; i < nitems(helpers); i++) {
2457 		if (unveil(helpers[i], "x") == 0)
2458 			continue;
2459 		return got_error_from_errno2("unveil", helpers[i]);
2460 	}
2461 
2462 	return NULL;
2463 }
2464 
2465 void
2466 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
2467 {
2468 	if (close(imsg_fds[0]) == -1) {
2469 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2470 		_exit(1);
2471 	}
2472 
2473 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
2474 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2475 		_exit(1);
2476 	}
2477 	if (closefrom(GOT_IMSG_FD_CHILD + 1) == -1) {
2478 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2479 		_exit(1);
2480 	}
2481 
2482 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
2483 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
2484 		    strerror(errno));
2485 		_exit(1);
2486 	}
2487 }