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