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, int list_refs_only,
417    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 	len = sizeof(struct got_imsg_fetch_request);
434 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
435 		close(fd);
436 		return got_error(GOT_ERR_NO_SPACE);
437 	}
438 
439 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_REQUEST, 0, 0, fd,
440 	    &fetchreq, sizeof(fetchreq)) == -1)
441 		return got_error_from_errno(
442 		    "imsg_compose FETCH_SERVER_PROGRESS");
443 
444 	err = flush_imsg(ibuf);
445 	if (err) {
446 		close(fd);
447 		return err;
448 	}
449 	fd = -1;
450 
451 	TAILQ_FOREACH(pe, have_refs, entry) {
452 		const char *name = pe->path;
453 		size_t name_len = pe->path_len;
454 		struct got_object_id *id = pe->data;
455 
456 		len = sizeof(struct got_imsg_fetch_have_ref) + name_len;
457 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_HAVE_REF, 0, 0, len);
458 		if (wbuf == NULL)
459 			return got_error_from_errno("imsg_create FETCH_HAVE_REF");
460 
461 		/* Keep in sync with struct got_imsg_fetch_have_ref! */
462 		if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1) {
463 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
464 			ibuf_free(wbuf);
465 			return err;
466 		}
467 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
468 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
469 			ibuf_free(wbuf);
470 			return err;
471 		}
472 		if (imsg_add(wbuf, name, name_len) == -1) {
473 			err = got_error_from_errno("imsg_add FETCH_HAVE_REF");
474 			ibuf_free(wbuf);
475 			return err;
476 		}
477 
478 		wbuf->fd = -1;
479 		imsg_close(ibuf, wbuf);
480 		err = flush_imsg(ibuf);
481 		if (err)
482 			return err;
483 	}
484 
485 	TAILQ_FOREACH(pe, wanted_branches, entry) {
486 		const char *name = pe->path;
487 		size_t name_len = pe->path_len;
488 
489 		len = sizeof(struct got_imsg_fetch_wanted_branch) + name_len;
490 		wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_WANTED_BRANCH, 0, 0,
491 		    len);
492 		if (wbuf == NULL)
493 			return got_error_from_errno(
494 			     "imsg_create FETCH_WANTED_BRANCH");
495 
496 		/* Keep in sync with struct got_imsg_fetch_wanted_branch! */
497 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
498 			err = got_error_from_errno(
499 			    "imsg_add FETCH_WANTED_BRANCH");
500 			ibuf_free(wbuf);
501 			return err;
502 		}
503 		if (imsg_add(wbuf, name, name_len) == -1) {
504 			err = got_error_from_errno(
505 			     "imsg_add FETCH_WANTED_BRANCH");
506 			ibuf_free(wbuf);
507 			return err;
508 		}
509 
510 		wbuf->fd = -1;
511 		imsg_close(ibuf, wbuf);
512 		err = flush_imsg(ibuf);
513 		if (err)
514 			return err;
515 	}
516 
517 	return NULL;
518 
519 }
520 
521 const struct got_error *
522 got_privsep_send_fetch_outfd(struct imsgbuf *ibuf, int fd)
523 {
524 	return send_fd(ibuf, GOT_IMSG_FETCH_OUTFD, fd);
525 }
526 
527 
528 const struct got_error *
529 got_privsep_send_fetch_symrefs(struct imsgbuf *ibuf,
530     struct got_pathlist_head *symrefs)
531 {
532 	const struct got_error *err = NULL;
533 	struct ibuf *wbuf;
534 	size_t len, nsymrefs = 0;
535 	struct got_pathlist_entry *pe;
536 
537 	len = sizeof(struct got_imsg_fetch_symrefs);
538 	TAILQ_FOREACH(pe, symrefs, entry) {
539 		const char *target = pe->data;
540 		len += sizeof(struct got_imsg_fetch_symref) +
541 		    pe->path_len + strlen(target);
542 		nsymrefs++;
543 	}
544 
545 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
546 		return got_error(GOT_ERR_NO_SPACE);
547 
548 	wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_SYMREFS, 0, 0, len);
549 	if (wbuf == NULL)
550 		return got_error_from_errno("imsg_create FETCH_SYMREFS");
551 
552 	/* Keep in sync with struct got_imsg_fetch_symrefs definition! */
553 	if (imsg_add(wbuf, &nsymrefs, sizeof(nsymrefs)) == -1) {
554 		err = got_error_from_errno("imsg_add FETCH_SYMREFS");
555 		ibuf_free(wbuf);
556 		return err;
557 	}
558 
559 	TAILQ_FOREACH(pe, symrefs, entry) {
560 		const char *name = pe->path;
561 		size_t name_len = pe->path_len;
562 		const char *target = pe->data;
563 		size_t target_len = strlen(target);
564 
565 		/* Keep in sync with struct got_imsg_fetch_symref definition! */
566 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
567 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
568 			ibuf_free(wbuf);
569 			return err;
570 		}
571 		if (imsg_add(wbuf, &target_len, sizeof(target_len)) == -1) {
572 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
573 			ibuf_free(wbuf);
574 			return err;
575 		}
576 		if (imsg_add(wbuf, name, name_len) == -1) {
577 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
578 			ibuf_free(wbuf);
579 			return err;
580 		}
581 		if (imsg_add(wbuf, target, target_len) == -1) {
582 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
583 			ibuf_free(wbuf);
584 			return err;
585 		}
586 	}
587 
588 	wbuf->fd = -1;
589 	imsg_close(ibuf, wbuf);
590 	return flush_imsg(ibuf);
591 }
592 
593 const struct got_error *
594 got_privsep_send_fetch_ref(struct imsgbuf *ibuf,
595     struct got_object_id *refid, const char *refname)
596 {
597 	const struct got_error *err = NULL;
598 	struct ibuf *wbuf;
599 	size_t len, reflen = strlen(refname);
600 
601 	len = sizeof(struct got_imsg_fetch_ref) + reflen;
602 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
603 		return got_error(GOT_ERR_NO_SPACE);
604 
605 	wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_REF, 0, 0, len);
606 	if (wbuf == NULL)
607 		return got_error_from_errno("imsg_create FETCH_REF");
608 
609 	/* Keep in sync with struct got_imsg_fetch_ref definition! */
610 	if (imsg_add(wbuf, refid->sha1, SHA1_DIGEST_LENGTH) == -1) {
611 		err = got_error_from_errno("imsg_add FETCH_REF");
612 		ibuf_free(wbuf);
613 		return err;
614 	}
615 	if (imsg_add(wbuf, refname, reflen) == -1) {
616 		err = got_error_from_errno("imsg_add FETCH_REF");
617 		ibuf_free(wbuf);
618 		return err;
619 	}
620 
621 	wbuf->fd = -1;
622 	imsg_close(ibuf, wbuf);
623 	return flush_imsg(ibuf);
624 }
625 
626 const struct got_error *
627 got_privsep_send_fetch_server_progress(struct imsgbuf *ibuf, const char *msg,
628     size_t msglen)
629 {
630 	if (msglen > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
631 		return got_error(GOT_ERR_NO_SPACE);
632 
633 	if (msglen == 0)
634 		return NULL;
635 
636 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_SERVER_PROGRESS, 0, 0, -1,
637 	    msg, msglen) == -1)
638 		return got_error_from_errno(
639 		    "imsg_compose FETCH_SERVER_PROGRESS");
640 
641 	return flush_imsg(ibuf);
642 }
643 
644 const struct got_error *
645 got_privsep_send_fetch_download_progress(struct imsgbuf *ibuf, off_t bytes)
646 {
647 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_DOWNLOAD_PROGRESS, 0, 0, -1,
648 	    &bytes, sizeof(bytes)) == -1)
649 		return got_error_from_errno(
650 		    "imsg_compose FETCH_DOWNLOAD_PROGRESS");
651 
652 	return flush_imsg(ibuf);
653 }
654 
655 const struct got_error *
656 got_privsep_send_fetch_done(struct imsgbuf *ibuf, struct got_object_id hash)
657 {
658 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_DONE, 0, 0, -1,
659 	    hash.sha1, SHA1_DIGEST_LENGTH) == -1)
660 		return got_error_from_errno("imsg_compose FETCH");
661 	return flush_imsg(ibuf);
662 }
663 
664 
665 const struct got_error *
666 got_privsep_recv_fetch_progress(int *done, struct got_object_id **id,
667     char **refname, struct got_pathlist_head *symrefs, char **server_progress,
668     off_t *packfile_size, struct imsgbuf *ibuf)
669 {
670 	const struct got_error *err = NULL;
671 	struct imsg imsg;
672 	size_t datalen;
673 	struct got_imsg_fetch_symrefs *isymrefs = NULL;
674 	size_t n, remain;
675 	off_t off;
676 	int i;
677 
678 	*done = 0;
679 	*id = NULL;
680 	*refname = NULL;
681 	*server_progress = NULL;
682 	*packfile_size = 0;
683 
684 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
685 	if (err)
686 		return err;
687 
688 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
689 	switch (imsg.hdr.type) {
690 	case GOT_IMSG_ERROR:
691 		if (datalen < sizeof(struct got_imsg_error)) {
692 			err = got_error(GOT_ERR_PRIVSEP_LEN);
693 			break;
694 		}
695 		err = recv_imsg_error(&imsg, datalen);
696 		break;
697 	case GOT_IMSG_FETCH_SYMREFS:
698 		if (datalen < sizeof(*isymrefs)) {
699 			err = got_error(GOT_ERR_PRIVSEP_LEN);
700 			break;
701 		}
702 		if (isymrefs != NULL) {
703 			err = got_error(GOT_ERR_PRIVSEP_MSG);
704 			break;
705 		}
706 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
707 		off = sizeof(*isymrefs);
708 		remain = datalen - off;
709 		for (n = 0; n < isymrefs->nsymrefs; n++) {
710 			struct got_imsg_fetch_symref *s;
711 			char *name, *target;
712 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
713 				err = got_error(GOT_ERR_PRIVSEP_LEN);
714 				goto done;
715 			}
716 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
717 			off += sizeof(*s);
718 			remain -= sizeof(*s);
719 			if (remain < s->name_len) {
720 				err = got_error(GOT_ERR_PRIVSEP_LEN);
721 				goto done;
722 			}
723 			name = strndup(imsg.data + off, s->name_len);
724 			if (name == NULL) {
725 				err = got_error_from_errno("strndup");
726 				goto done;
727 			}
728 			off += s->name_len;
729 			remain -= s->name_len;
730 			if (remain < s->target_len) {
731 				err = got_error(GOT_ERR_PRIVSEP_LEN);
732 				free(name);
733 				goto done;
734 			}
735 			target = strndup(imsg.data + off, s->target_len);
736 			if (target == NULL) {
737 				err = got_error_from_errno("strndup");
738 				free(name);
739 				goto done;
740 			}
741 			off += s->target_len;
742 			remain -= s->target_len;
743 			err = got_pathlist_append(symrefs, name, target);
744 			if (err) {
745 				free(name);
746 				free(target);
747 				goto done;
748 			}
749 		}
750 		break;
751 	case GOT_IMSG_FETCH_REF:
752 		if (datalen <= SHA1_DIGEST_LENGTH) {
753 			err = got_error(GOT_ERR_PRIVSEP_MSG);
754 			break;
755 		}
756 		*id = malloc(sizeof(**id));
757 		if (*id == NULL) {
758 			err = got_error_from_errno("malloc");
759 			break;
760 		}
761 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
762 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
763 		    datalen - SHA1_DIGEST_LENGTH);
764 		if (*refname == NULL) {
765 			err = got_error_from_errno("strndup");
766 			break;
767 		}
768 		break;
769 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
770 		if (datalen == 0) {
771 			err = got_error(GOT_ERR_PRIVSEP_LEN);
772 			break;
773 		}
774 		*server_progress = strndup(imsg.data, datalen);
775 		if (*server_progress == NULL) {
776 			err = got_error_from_errno("strndup");
777 			break;
778 		}
779 		for (i = 0; i < datalen; i++) {
780 			if (!isprint((unsigned char)(*server_progress)[i]) &&
781 			    !isspace((unsigned char)(*server_progress)[i])) {
782 				err = got_error(GOT_ERR_PRIVSEP_MSG);
783 				free(*server_progress);
784 				*server_progress = NULL;
785 				goto done;
786 			}
787 		}
788 		break;
789 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
790 		if (datalen < sizeof(*packfile_size)) {
791 			err = got_error(GOT_ERR_PRIVSEP_MSG);
792 			break;
793 		}
794 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
795 		break;
796 	case GOT_IMSG_FETCH_DONE:
797 		*id = malloc(sizeof(**id));
798 		if (*id == NULL) {
799 			err = got_error_from_errno("malloc");
800 			break;
801 		}
802 		if (datalen != SHA1_DIGEST_LENGTH) {
803 			err = got_error(GOT_ERR_PRIVSEP_MSG);
804 			break;
805 		}
806 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
807 		*done = 1;
808 		break;
809 	default:
810 		err = got_error(GOT_ERR_PRIVSEP_MSG);
811 		break;
812 	}
813 done:
814 	if (err) {
815 		free(*id);
816 		*id = NULL;
817 		free(*refname);
818 		*refname = NULL;
819 	}
820 	imsg_free(&imsg);
821 	return err;
822 }
823 
824 const struct got_error *
825 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_hash,
826     int fd)
827 {
828 	const struct got_error *err = NULL;
829 
830 	/* Keep in sync with struct got_imsg_index_pack_request */
831 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
832 	    pack_hash, SHA1_DIGEST_LENGTH) == -1) {
833 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
834 		close(fd);
835 		return err;
836 	}
837 	return flush_imsg(ibuf);
838 }
839 
840 const struct got_error *
841 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
842 {
843 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
844 }
845 
846 const struct got_error *
847 got_privsep_send_index_pack_progress(struct imsgbuf *ibuf, int nobj_total,
848     int nobj_indexed, int nobj_loose, int nobj_resolved)
849 {
850 	struct got_imsg_index_pack_progress iprogress;
851 
852 	iprogress.nobj_total = nobj_total;
853 	iprogress.nobj_indexed = nobj_indexed;
854 	iprogress.nobj_loose = nobj_loose;
855 	iprogress.nobj_resolved = nobj_resolved;
856 
857 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_PROGRESS, 0, 0, -1,
858 	    &iprogress, sizeof(iprogress)) == -1)
859 		return got_error_from_errno("imsg_compose IDXPACK_PROGRESS");
860 
861 	return flush_imsg(ibuf);
862 }
863 
864 const struct got_error *
865 got_privsep_send_index_pack_done(struct imsgbuf *ibuf)
866 {
867 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_DONE, 0, 0, -1, NULL, 0) == -1)
868 		return got_error_from_errno("imsg_compose FETCH");
869 	return flush_imsg(ibuf);
870 }
871 
872 const struct got_error *
873 got_privsep_recv_index_progress(int *done, int *nobj_total,
874     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
875     struct imsgbuf *ibuf)
876 {
877 	const struct got_error *err = NULL;
878 	struct imsg imsg;
879 	struct got_imsg_index_pack_progress *iprogress;
880 	size_t datalen;
881 
882 	*done = 0;
883 	*nobj_total = 0;
884 	*nobj_indexed = 0;
885 	*nobj_resolved = 0;
886 
887 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
888 	if (err)
889 		return err;
890 
891 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
892 	switch (imsg.hdr.type) {
893 	case GOT_IMSG_ERROR:
894 		if (datalen < sizeof(struct got_imsg_error)) {
895 			err = got_error(GOT_ERR_PRIVSEP_LEN);
896 			break;
897 		}
898 		err = recv_imsg_error(&imsg, datalen);
899 		break;
900 	case GOT_IMSG_IDXPACK_PROGRESS:
901 		if (datalen < sizeof(*iprogress)) {
902 			err = got_error(GOT_ERR_PRIVSEP_LEN);
903 			break;
904 		}
905 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
906 		*nobj_total = iprogress->nobj_total;
907 		*nobj_indexed = iprogress->nobj_indexed;
908 		*nobj_loose = iprogress->nobj_loose;
909 		*nobj_resolved = iprogress->nobj_resolved;
910 		break;
911 	case GOT_IMSG_IDXPACK_DONE:
912 		if (datalen != 0) {
913 			err = got_error(GOT_ERR_PRIVSEP_LEN);
914 			break;
915 		}
916 		*done = 1;
917 		break;
918 	default:
919 		err = got_error(GOT_ERR_PRIVSEP_MSG);
920 		break;
921 	}
922 
923 	imsg_free(&imsg);
924 	return err;
925 }
926 
927 const struct got_error *
928 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
929     struct imsgbuf *ibuf)
930 {
931 	const struct got_error *err = NULL;
932 	struct got_imsg_object *iobj;
933 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
934 
935 	if (datalen != sizeof(*iobj))
936 		return got_error(GOT_ERR_PRIVSEP_LEN);
937 	iobj = imsg->data;
938 
939 	*obj = calloc(1, sizeof(**obj));
940 	if (*obj == NULL)
941 		return got_error_from_errno("calloc");
942 
943 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
944 	(*obj)->type = iobj->type;
945 	(*obj)->flags = iobj->flags;
946 	(*obj)->hdrlen = iobj->hdrlen;
947 	(*obj)->size = iobj->size;
948 	/* path_packfile is handled by caller */
949 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
950 		(*obj)->pack_offset = iobj->pack_offset;
951 		(*obj)->pack_idx = iobj->pack_idx;
952 	}
953 
954 	return err;
955 }
956 
957 const struct got_error *
958 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
959 {
960 	const struct got_error *err = NULL;
961 	struct imsg imsg;
962 	const size_t min_datalen =
963 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
964 
965 	*obj = NULL;
966 
967 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
968 	if (err)
969 		return err;
970 
971 	switch (imsg.hdr.type) {
972 	case GOT_IMSG_OBJECT:
973 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
974 		break;
975 	default:
976 		err = got_error(GOT_ERR_PRIVSEP_MSG);
977 		break;
978 	}
979 
980 	imsg_free(&imsg);
981 
982 	return err;
983 }
984 
985 static const struct got_error *
986 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
987     size_t logmsg_len)
988 {
989 	const struct got_error *err = NULL;
990 	size_t offset, remain;
991 
992 	offset = 0;
993 	remain = logmsg_len;
994 	while (remain > 0) {
995 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
996 
997 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
998 		    commit->logmsg + offset, n) == -1) {
999 			err = got_error_from_errno("imsg_compose "
1000 			    "COMMIT_LOGMSG");
1001 			break;
1002 		}
1003 
1004 		err = flush_imsg(ibuf);
1005 		if (err)
1006 			break;
1007 
1008 		offset += n;
1009 		remain -= n;
1010 	}
1011 
1012 	return err;
1013 }
1014 
1015 const struct got_error *
1016 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
1017 {
1018 	const struct got_error *err = NULL;
1019 	struct got_imsg_commit_object *icommit;
1020 	uint8_t *buf;
1021 	size_t len, total;
1022 	struct got_object_qid *qid;
1023 	size_t author_len = strlen(commit->author);
1024 	size_t committer_len = strlen(commit->committer);
1025 	size_t logmsg_len = strlen(commit->logmsg);
1026 
1027 	total = sizeof(*icommit) + author_len + committer_len +
1028 	    commit->nparents * SHA1_DIGEST_LENGTH;
1029 
1030 	buf = malloc(total);
1031 	if (buf == NULL)
1032 		return got_error_from_errno("malloc");
1033 
1034 	icommit = (struct got_imsg_commit_object *)buf;
1035 	memcpy(icommit->tree_id, commit->tree_id->sha1,
1036 	    sizeof(icommit->tree_id));
1037 	icommit->author_len = author_len;
1038 	icommit->author_time = commit->author_time;
1039 	icommit->author_gmtoff = commit->author_gmtoff;
1040 	icommit->committer_len = committer_len;
1041 	icommit->committer_time = commit->committer_time;
1042 	icommit->committer_gmtoff = commit->committer_gmtoff;
1043 	icommit->logmsg_len = logmsg_len;
1044 	icommit->nparents = commit->nparents;
1045 
1046 	len = sizeof(*icommit);
1047 	memcpy(buf + len, commit->author, author_len);
1048 	len += author_len;
1049 	memcpy(buf + len, commit->committer, committer_len);
1050 	len += committer_len;
1051 	SIMPLEQ_FOREACH(qid, &commit->parent_ids, entry) {
1052 		memcpy(buf + len, qid->id, SHA1_DIGEST_LENGTH);
1053 		len += SHA1_DIGEST_LENGTH;
1054 	}
1055 
1056 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
1057 		err = got_error_from_errno("imsg_compose COMMIT");
1058 		goto done;
1059 	}
1060 
1061 	if (logmsg_len == 0 ||
1062 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1063 		err = flush_imsg(ibuf);
1064 		if (err)
1065 			goto done;
1066 	}
1067 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
1068 done:
1069 	free(buf);
1070 	return err;
1071 }
1072 
1073 static const struct got_error *
1074 get_commit_from_imsg(struct got_commit_object **commit,
1075     struct imsg *imsg, size_t datalen, struct imsgbuf *ibuf)
1076 {
1077 	const struct got_error *err = NULL;
1078 	struct got_imsg_commit_object *icommit;
1079 	size_t len = 0;
1080 	int i;
1081 
1082 	if (datalen < sizeof(*icommit))
1083 		return got_error(GOT_ERR_PRIVSEP_LEN);
1084 
1085 	icommit = imsg->data;
1086 	if (datalen != sizeof(*icommit) + icommit->author_len +
1087 	    icommit->committer_len +
1088 	    icommit->nparents * SHA1_DIGEST_LENGTH)
1089 		return got_error(GOT_ERR_PRIVSEP_LEN);
1090 
1091 	if (icommit->nparents < 0)
1092 		return got_error(GOT_ERR_PRIVSEP_LEN);
1093 
1094 	len += sizeof(*icommit);
1095 
1096 	*commit = got_object_commit_alloc_partial();
1097 	if (*commit == NULL)
1098 		return got_error_from_errno(
1099 		    "got_object_commit_alloc_partial");
1100 
1101 	memcpy((*commit)->tree_id->sha1, icommit->tree_id,
1102 	    SHA1_DIGEST_LENGTH);
1103 	(*commit)->author_time = icommit->author_time;
1104 	(*commit)->author_gmtoff = icommit->author_gmtoff;
1105 	(*commit)->committer_time = icommit->committer_time;
1106 	(*commit)->committer_gmtoff = icommit->committer_gmtoff;
1107 
1108 	if (icommit->author_len == 0) {
1109 		(*commit)->author = strdup("");
1110 		if ((*commit)->author == NULL) {
1111 			err = got_error_from_errno("strdup");
1112 			goto done;
1113 		}
1114 	} else {
1115 		(*commit)->author = malloc(icommit->author_len + 1);
1116 		if ((*commit)->author == NULL) {
1117 			err = got_error_from_errno("malloc");
1118 			goto done;
1119 		}
1120 		memcpy((*commit)->author, imsg->data + len,
1121 		    icommit->author_len);
1122 		(*commit)->author[icommit->author_len] = '\0';
1123 	}
1124 	len += icommit->author_len;
1125 
1126 	if (icommit->committer_len == 0) {
1127 		(*commit)->committer = strdup("");
1128 		if ((*commit)->committer == NULL) {
1129 			err = got_error_from_errno("strdup");
1130 			goto done;
1131 		}
1132 	} else {
1133 		(*commit)->committer =
1134 		    malloc(icommit->committer_len + 1);
1135 		if ((*commit)->committer == NULL) {
1136 			err = got_error_from_errno("malloc");
1137 			goto done;
1138 		}
1139 		memcpy((*commit)->committer, imsg->data + len,
1140 		    icommit->committer_len);
1141 		(*commit)->committer[icommit->committer_len] = '\0';
1142 	}
1143 	len += icommit->committer_len;
1144 
1145 	if (icommit->logmsg_len == 0) {
1146 		(*commit)->logmsg = strdup("");
1147 		if ((*commit)->logmsg == NULL) {
1148 			err = got_error_from_errno("strdup");
1149 			goto done;
1150 		}
1151 	} else {
1152 		size_t offset = 0, remain = icommit->logmsg_len;
1153 
1154 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1155 		if ((*commit)->logmsg == NULL) {
1156 			err = got_error_from_errno("malloc");
1157 			goto done;
1158 		}
1159 		while (remain > 0) {
1160 			struct imsg imsg_log;
1161 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1162 			    remain);
1163 
1164 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1165 			if (err)
1166 				goto done;
1167 
1168 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1169 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1170 				goto done;
1171 			}
1172 
1173 			memcpy((*commit)->logmsg + offset,
1174 			    imsg_log.data, n);
1175 			imsg_free(&imsg_log);
1176 			offset += n;
1177 			remain -= n;
1178 		}
1179 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1180 	}
1181 
1182 	for (i = 0; i < icommit->nparents; i++) {
1183 		struct got_object_qid *qid;
1184 
1185 		err = got_object_qid_alloc_partial(&qid);
1186 		if (err)
1187 			break;
1188 		memcpy(qid->id, imsg->data + len +
1189 		    i * SHA1_DIGEST_LENGTH, sizeof(*qid->id));
1190 		SIMPLEQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1191 		(*commit)->nparents++;
1192 	}
1193 done:
1194 	if (err) {
1195 		got_object_commit_close(*commit);
1196 		*commit = NULL;
1197 	}
1198 	return err;
1199 }
1200 
1201 const struct got_error *
1202 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1203 {
1204 	const struct got_error *err = NULL;
1205 	struct imsg imsg;
1206 	size_t datalen;
1207 	const size_t min_datalen =
1208 	    MIN(sizeof(struct got_imsg_error),
1209 	    sizeof(struct got_imsg_commit_object));
1210 
1211 	*commit = NULL;
1212 
1213 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1214 	if (err)
1215 		return err;
1216 
1217 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1218 
1219 	switch (imsg.hdr.type) {
1220 	case GOT_IMSG_COMMIT:
1221 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1222 		break;
1223 	default:
1224 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1225 		break;
1226 	}
1227 
1228 	imsg_free(&imsg);
1229 
1230 	return err;
1231 }
1232 
1233 const struct got_error *
1234 got_privsep_send_tree(struct imsgbuf *ibuf, struct got_pathlist_head *entries,
1235     int nentries)
1236 {
1237 	const struct got_error *err = NULL;
1238 	struct got_imsg_tree_object itree;
1239 	struct got_pathlist_entry *pe;
1240 	size_t totlen;
1241 	int nimsg; /* number of imsg queued in ibuf */
1242 
1243 	itree.nentries = nentries;
1244 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1245 	    == -1)
1246 		return got_error_from_errno("imsg_compose TREE");
1247 
1248 	totlen = sizeof(itree);
1249 	nimsg = 1;
1250 	TAILQ_FOREACH(pe, entries, entry) {
1251 		const char *name = pe->path;
1252 		struct got_parsed_tree_entry *pte = pe->data;
1253 		struct ibuf *wbuf;
1254 		size_t namelen = strlen(name);
1255 		size_t len = sizeof(struct got_imsg_tree_entry) + namelen;
1256 
1257 		if (len > MAX_IMSGSIZE)
1258 			return got_error(GOT_ERR_NO_SPACE);
1259 
1260 		nimsg++;
1261 		if (totlen + len >= MAX_IMSGSIZE - (IMSG_HEADER_SIZE * nimsg)) {
1262 			err = flush_imsg(ibuf);
1263 			if (err)
1264 				return err;
1265 			nimsg = 0;
1266 		}
1267 
1268 		wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRY, 0, 0, len);
1269 		if (wbuf == NULL)
1270 			return got_error_from_errno("imsg_create TREE_ENTRY");
1271 
1272 		/* Keep in sync with struct got_imsg_tree_object definition! */
1273 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1) {
1274 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1275 			ibuf_free(wbuf);
1276 			return err;
1277 		}
1278 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1) {
1279 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1280 			ibuf_free(wbuf);
1281 			return err;
1282 		}
1283 
1284 		if (imsg_add(wbuf, name, namelen) == -1) {
1285 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1286 			ibuf_free(wbuf);
1287 			return err;
1288 		}
1289 
1290 		wbuf->fd = -1;
1291 		imsg_close(ibuf, wbuf);
1292 
1293 		totlen += len;
1294 	}
1295 
1296 	return flush_imsg(ibuf);
1297 }
1298 
1299 const struct got_error *
1300 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1301 {
1302 	const struct got_error *err = NULL;
1303 	const size_t min_datalen =
1304 	    MIN(sizeof(struct got_imsg_error),
1305 	    sizeof(struct got_imsg_tree_object));
1306 	struct got_imsg_tree_object *itree;
1307 	int nentries = 0;
1308 
1309 	*tree = NULL;
1310 get_more:
1311 	err = read_imsg(ibuf);
1312 	if (err)
1313 		goto done;
1314 
1315 	for (;;) {
1316 		struct imsg imsg;
1317 		size_t n;
1318 		size_t datalen;
1319 		struct got_imsg_tree_entry *ite;
1320 		struct got_tree_entry *te = NULL;
1321 
1322 		n = imsg_get(ibuf, &imsg);
1323 		if (n == 0) {
1324 			if (*tree && (*tree)->nentries != nentries)
1325 				goto get_more;
1326 			break;
1327 		}
1328 
1329 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen)
1330 			return got_error(GOT_ERR_PRIVSEP_LEN);
1331 
1332 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1333 
1334 		switch (imsg.hdr.type) {
1335 		case GOT_IMSG_ERROR:
1336 			err = recv_imsg_error(&imsg, datalen);
1337 			break;
1338 		case GOT_IMSG_TREE:
1339 			/* This message should only appear once. */
1340 			if (*tree != NULL) {
1341 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1342 				break;
1343 			}
1344 			if (datalen != sizeof(*itree)) {
1345 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1346 				break;
1347 			}
1348 			itree = imsg.data;
1349 			*tree = malloc(sizeof(**tree));
1350 			if (*tree == NULL) {
1351 				err = got_error_from_errno("malloc");
1352 				break;
1353 			}
1354 			(*tree)->entries = calloc(itree->nentries,
1355 			    sizeof(struct got_tree_entry));
1356 			if ((*tree)->entries == NULL) {
1357 				err = got_error_from_errno("malloc");
1358 				break;
1359 			}
1360 			(*tree)->nentries = itree->nentries;
1361 			(*tree)->refcnt = 0;
1362 			break;
1363 		case GOT_IMSG_TREE_ENTRY:
1364 			/* This message should be preceeded by GOT_IMSG_TREE. */
1365 			if (*tree == NULL) {
1366 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1367 				break;
1368 			}
1369 			if (datalen < sizeof(*ite) || datalen > MAX_IMSGSIZE) {
1370 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1371 				break;
1372 			}
1373 
1374 			/* Remaining data contains the entry's name. */
1375 			datalen -= sizeof(*ite);
1376 			if (datalen == 0 || datalen > MAX_IMSGSIZE) {
1377 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1378 				break;
1379 			}
1380 			ite = imsg.data;
1381 
1382 			if (datalen + 1 > sizeof(te->name)) {
1383 				err = got_error(GOT_ERR_NO_SPACE);
1384 				break;
1385 			}
1386 			te = &(*tree)->entries[nentries];
1387 			memcpy(te->name, imsg.data + sizeof(*ite), datalen);
1388 			te->name[datalen] = '\0';
1389 
1390 			memcpy(te->id.sha1, ite->id, SHA1_DIGEST_LENGTH);
1391 			te->mode = ite->mode;
1392 			te->idx = nentries;
1393 			nentries++;
1394 			break;
1395 		default:
1396 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1397 			break;
1398 		}
1399 
1400 		imsg_free(&imsg);
1401 	}
1402 done:
1403 	if (*tree && (*tree)->nentries != nentries) {
1404 		if (err == NULL)
1405 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1406 		got_object_tree_close(*tree);
1407 		*tree = NULL;
1408 	}
1409 
1410 	return err;
1411 }
1412 
1413 const struct got_error *
1414 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1415     const uint8_t *data)
1416 {
1417 	struct got_imsg_blob iblob;
1418 
1419 	iblob.size = size;
1420 	iblob.hdrlen = hdrlen;
1421 
1422 	if (data) {
1423 		uint8_t *buf;
1424 
1425 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1426 			return got_error(GOT_ERR_NO_SPACE);
1427 
1428 		buf = malloc(sizeof(iblob) + size);
1429 		if (buf == NULL)
1430 			return got_error_from_errno("malloc");
1431 
1432 		memcpy(buf, &iblob, sizeof(iblob));
1433 		memcpy(buf + sizeof(iblob), data, size);
1434 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1435 		   sizeof(iblob) + size) == -1) {
1436 			free(buf);
1437 			return got_error_from_errno("imsg_compose BLOB");
1438 		}
1439 		free(buf);
1440 	} else {
1441 		/* Data has already been written to file descriptor. */
1442 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1443 		    sizeof(iblob)) == -1)
1444 			return got_error_from_errno("imsg_compose BLOB");
1445 	}
1446 
1447 
1448 	return flush_imsg(ibuf);
1449 }
1450 
1451 const struct got_error *
1452 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1453     struct imsgbuf *ibuf)
1454 {
1455 	const struct got_error *err = NULL;
1456 	struct imsg imsg;
1457 	struct got_imsg_blob *iblob;
1458 	size_t datalen;
1459 
1460 	*outbuf = NULL;
1461 
1462 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1463 	if (err)
1464 		return err;
1465 
1466 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1467 
1468 	switch (imsg.hdr.type) {
1469 	case GOT_IMSG_BLOB:
1470 		if (datalen < sizeof(*iblob)) {
1471 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1472 			break;
1473 		}
1474 		iblob = imsg.data;
1475 		*size = iblob->size;
1476 		*hdrlen = iblob->hdrlen;
1477 
1478 		if (datalen == sizeof(*iblob)) {
1479 			/* Data has been written to file descriptor. */
1480 			break;
1481 		}
1482 
1483 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX) {
1484 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1485 			break;
1486 		}
1487 
1488 		*outbuf = malloc(*size);
1489 		if (*outbuf == NULL) {
1490 			err = got_error_from_errno("malloc");
1491 			break;
1492 		}
1493 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1494 		break;
1495 	default:
1496 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1497 		break;
1498 	}
1499 
1500 	imsg_free(&imsg);
1501 
1502 	return err;
1503 }
1504 
1505 static const struct got_error *
1506 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1507 {
1508 	const struct got_error *err = NULL;
1509 	size_t offset, remain;
1510 
1511 	offset = 0;
1512 	remain = tagmsg_len;
1513 	while (remain > 0) {
1514 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1515 
1516 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1517 		    tag->tagmsg + offset, n) == -1) {
1518 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1519 			break;
1520 		}
1521 
1522 		err = flush_imsg(ibuf);
1523 		if (err)
1524 			break;
1525 
1526 		offset += n;
1527 		remain -= n;
1528 	}
1529 
1530 	return err;
1531 }
1532 
1533 const struct got_error *
1534 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1535 {
1536 	const struct got_error *err = NULL;
1537 	struct got_imsg_tag_object *itag;
1538 	uint8_t *buf;
1539 	size_t len, total;
1540 	size_t tag_len = strlen(tag->tag);
1541 	size_t tagger_len = strlen(tag->tagger);
1542 	size_t tagmsg_len = strlen(tag->tagmsg);
1543 
1544 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1545 
1546 	buf = malloc(total);
1547 	if (buf == NULL)
1548 		return got_error_from_errno("malloc");
1549 
1550 	itag = (struct got_imsg_tag_object *)buf;
1551 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1552 	itag->obj_type = tag->obj_type;
1553 	itag->tag_len = tag_len;
1554 	itag->tagger_len = tagger_len;
1555 	itag->tagger_time = tag->tagger_time;
1556 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1557 	itag->tagmsg_len = tagmsg_len;
1558 
1559 	len = sizeof(*itag);
1560 	memcpy(buf + len, tag->tag, tag_len);
1561 	len += tag_len;
1562 	memcpy(buf + len, tag->tagger, tagger_len);
1563 	len += tagger_len;
1564 
1565 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1566 		err = got_error_from_errno("imsg_compose TAG");
1567 		goto done;
1568 	}
1569 
1570 	if (tagmsg_len == 0 ||
1571 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1572 		err = flush_imsg(ibuf);
1573 		if (err)
1574 			goto done;
1575 	}
1576 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1577 done:
1578 	free(buf);
1579 	return err;
1580 }
1581 
1582 const struct got_error *
1583 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1584 {
1585 	const struct got_error *err = NULL;
1586 	struct imsg imsg;
1587 	struct got_imsg_tag_object *itag;
1588 	size_t len, datalen;
1589 	const size_t min_datalen =
1590 	    MIN(sizeof(struct got_imsg_error),
1591 	    sizeof(struct got_imsg_tag_object));
1592 
1593 	*tag = NULL;
1594 
1595 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1596 	if (err)
1597 		return err;
1598 
1599 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1600 	len = 0;
1601 
1602 	switch (imsg.hdr.type) {
1603 	case GOT_IMSG_TAG:
1604 		if (datalen < sizeof(*itag)) {
1605 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1606 			break;
1607 		}
1608 		itag = imsg.data;
1609 		if (datalen != sizeof(*itag) + itag->tag_len +
1610 		    itag->tagger_len) {
1611 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1612 			break;
1613 		}
1614 		len += sizeof(*itag);
1615 
1616 		*tag = calloc(1, sizeof(**tag));
1617 		if (*tag == NULL) {
1618 			err = got_error_from_errno("calloc");
1619 			break;
1620 		}
1621 
1622 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1623 
1624 		if (itag->tag_len == 0) {
1625 			(*tag)->tag = strdup("");
1626 			if ((*tag)->tag == NULL) {
1627 				err = got_error_from_errno("strdup");
1628 				break;
1629 			}
1630 		} else {
1631 			(*tag)->tag = malloc(itag->tag_len + 1);
1632 			if ((*tag)->tag == NULL) {
1633 				err = got_error_from_errno("malloc");
1634 				break;
1635 			}
1636 			memcpy((*tag)->tag, imsg.data + len,
1637 			    itag->tag_len);
1638 			(*tag)->tag[itag->tag_len] = '\0';
1639 		}
1640 		len += itag->tag_len;
1641 
1642 		(*tag)->obj_type = itag->obj_type;
1643 		(*tag)->tagger_time = itag->tagger_time;
1644 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1645 
1646 		if (itag->tagger_len == 0) {
1647 			(*tag)->tagger = strdup("");
1648 			if ((*tag)->tagger == NULL) {
1649 				err = got_error_from_errno("strdup");
1650 				break;
1651 			}
1652 		} else {
1653 			(*tag)->tagger = malloc(itag->tagger_len + 1);
1654 			if ((*tag)->tagger == NULL) {
1655 				err = got_error_from_errno("malloc");
1656 				break;
1657 			}
1658 			memcpy((*tag)->tagger, imsg.data + len,
1659 			    itag->tagger_len);
1660 			(*tag)->tagger[itag->tagger_len] = '\0';
1661 		}
1662 		len += itag->tagger_len;
1663 
1664 		if (itag->tagmsg_len == 0) {
1665 			(*tag)->tagmsg = strdup("");
1666 			if ((*tag)->tagmsg == NULL) {
1667 				err = got_error_from_errno("strdup");
1668 				break;
1669 			}
1670 		} else {
1671 			size_t offset = 0, remain = itag->tagmsg_len;
1672 
1673 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1674 			if ((*tag)->tagmsg == NULL) {
1675 				err = got_error_from_errno("malloc");
1676 				break;
1677 			}
1678 			while (remain > 0) {
1679 				struct imsg imsg_log;
1680 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1681 				    remain);
1682 
1683 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1684 				if (err)
1685 					return err;
1686 
1687 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1688 					return got_error(GOT_ERR_PRIVSEP_MSG);
1689 
1690 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1691 				    n);
1692 				imsg_free(&imsg_log);
1693 				offset += n;
1694 				remain -= n;
1695 			}
1696 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1697 		}
1698 
1699 		break;
1700 	default:
1701 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1702 		break;
1703 	}
1704 
1705 	imsg_free(&imsg);
1706 
1707 	return err;
1708 }
1709 
1710 const struct got_error *
1711 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1712     struct got_packidx *packidx)
1713 {
1714 	const struct got_error *err = NULL;
1715 	struct got_imsg_packidx ipackidx;
1716 	struct got_imsg_pack ipack;
1717 	int fd;
1718 
1719 	ipackidx.len = packidx->len;
1720 	fd = dup(packidx->fd);
1721 	if (fd == -1)
1722 		return got_error_from_errno("dup");
1723 
1724 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
1725 	    sizeof(ipackidx)) == -1) {
1726 		err = got_error_from_errno("imsg_compose PACKIDX");
1727 		close(fd);
1728 		return err;
1729 	}
1730 
1731 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
1732 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
1733 		return got_error(GOT_ERR_NO_SPACE);
1734 	ipack.filesize = pack->filesize;
1735 
1736 	fd = dup(pack->fd);
1737 	if (fd == -1)
1738 		return got_error_from_errno("dup");
1739 
1740 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
1741 	    == -1) {
1742 		err = got_error_from_errno("imsg_compose PACK");
1743 		close(fd);
1744 		return err;
1745 	}
1746 
1747 	return flush_imsg(ibuf);
1748 }
1749 
1750 const struct got_error *
1751 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
1752     struct got_object_id *id)
1753 {
1754 	struct got_imsg_packed_object iobj;
1755 
1756 	iobj.idx = idx;
1757 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
1758 
1759 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
1760 	    &iobj, sizeof(iobj)) == -1)
1761 		return got_error_from_errno("imsg_compose "
1762 		    "PACKED_OBJECT_REQUEST");
1763 
1764 	return flush_imsg(ibuf);
1765 }
1766 
1767 const struct got_error *
1768 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
1769 {
1770 	const struct got_error *err = NULL;
1771 
1772 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
1773 	    NULL, 0) == -1) {
1774 		err = got_error_from_errno("imsg_compose "
1775 		    "GITCONFIG_PARSE_REQUEST");
1776 		close(fd);
1777 		return err;
1778 	}
1779 
1780 	return flush_imsg(ibuf);
1781 }
1782 
1783 const struct got_error *
1784 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
1785 {
1786 	if (imsg_compose(ibuf,
1787 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
1788 	    NULL, 0) == -1)
1789 		return got_error_from_errno("imsg_compose "
1790 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
1791 
1792 	return flush_imsg(ibuf);
1793 }
1794 
1795 const struct got_error *
1796 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
1797 {
1798 	if (imsg_compose(ibuf,
1799 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
1800 		return got_error_from_errno("imsg_compose "
1801 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
1802 
1803 	return flush_imsg(ibuf);
1804 }
1805 
1806 const struct got_error *
1807 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
1808 {
1809 	if (imsg_compose(ibuf,
1810 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
1811 		return got_error_from_errno("imsg_compose "
1812 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
1813 
1814 	return flush_imsg(ibuf);
1815 }
1816 
1817 const struct got_error *
1818 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
1819 {
1820 	if (imsg_compose(ibuf,
1821 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
1822 		return got_error_from_errno("imsg_compose "
1823 		    "GITCONFIG_REMOTE_REQUEST");
1824 
1825 	return flush_imsg(ibuf);
1826 }
1827 
1828 const struct got_error *
1829 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
1830 {
1831 	if (imsg_compose(ibuf,
1832 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
1833 		return got_error_from_errno("imsg_compose "
1834 		    "GITCONFIG_OWNER_REQUEST");
1835 
1836 	return flush_imsg(ibuf);
1837 }
1838 
1839 const struct got_error *
1840 got_privsep_send_gitconfig_str(struct imsgbuf *ibuf, const char *value)
1841 {
1842 	size_t len = value ? strlen(value) + 1 : 0;
1843 
1844 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_STR_VAL, 0, 0, -1,
1845 	    value, len) == -1)
1846 		return got_error_from_errno("imsg_compose GITCONFIG_STR_VAL");
1847 
1848 	return flush_imsg(ibuf);
1849 }
1850 
1851 const struct got_error *
1852 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
1853 {
1854 	const struct got_error *err = NULL;
1855 	struct imsg imsg;
1856 	size_t datalen;
1857 	const size_t min_datalen = 0;
1858 
1859 	*str = NULL;
1860 
1861 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1862 	if (err)
1863 		return err;
1864 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1865 
1866 	switch (imsg.hdr.type) {
1867 	case GOT_IMSG_GITCONFIG_STR_VAL:
1868 		if (datalen == 0)
1869 			break;
1870 		*str = malloc(datalen);
1871 		if (*str == NULL) {
1872 			err = got_error_from_errno("malloc");
1873 			break;
1874 		}
1875 		if (strlcpy(*str, imsg.data, datalen) >= datalen)
1876 			err = got_error(GOT_ERR_NO_SPACE);
1877 		break;
1878 	default:
1879 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1880 		break;
1881 	}
1882 
1883 	imsg_free(&imsg);
1884 	return err;
1885 }
1886 
1887 const struct got_error *
1888 got_privsep_send_gitconfig_int(struct imsgbuf *ibuf, int value)
1889 {
1890 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_INT_VAL, 0, 0, -1,
1891 	    &value, sizeof(value)) == -1)
1892 		return got_error_from_errno("imsg_compose GITCONFIG_INT_VAL");
1893 
1894 	return flush_imsg(ibuf);
1895 }
1896 
1897 const struct got_error *
1898 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
1899 {
1900 	const struct got_error *err = NULL;
1901 	struct imsg imsg;
1902 	size_t datalen;
1903 	const size_t min_datalen =
1904 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
1905 
1906 	*val = 0;
1907 
1908 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1909 	if (err)
1910 		return err;
1911 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1912 
1913 	switch (imsg.hdr.type) {
1914 	case GOT_IMSG_GITCONFIG_INT_VAL:
1915 		if (datalen != sizeof(*val)) {
1916 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1917 			break;
1918 		}
1919 		memcpy(val, imsg.data, sizeof(*val));
1920 		break;
1921 	default:
1922 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1923 		break;
1924 	}
1925 
1926 	imsg_free(&imsg);
1927 	return err;
1928 }
1929 
1930 const struct got_error *
1931 got_privsep_send_gitconfig_remotes(struct imsgbuf *ibuf,
1932     struct got_remote_repo *remotes, int nremotes)
1933 {
1934 	const struct got_error *err = NULL;
1935 	struct got_imsg_remotes iremotes;
1936 	int i;
1937 
1938 	iremotes.nremotes = nremotes;
1939 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_REMOTES, 0, 0, -1,
1940 	    &iremotes, sizeof(iremotes)) == -1)
1941 		return got_error_from_errno("imsg_compose GITCONFIG_REMOTES");
1942 
1943 	err = flush_imsg(ibuf);
1944 	imsg_clear(ibuf);
1945 	if (err)
1946 		return err;
1947 
1948 	for (i = 0; i < nremotes; i++) {
1949 		struct got_imsg_remote iremote;
1950 		size_t len = sizeof(iremote);
1951 		struct ibuf *wbuf;
1952 
1953 		iremote.mirror_references = remotes[i].mirror_references;
1954 		iremote.name_len = strlen(remotes[i].name);
1955 		len += iremote.name_len;
1956 		iremote.url_len = strlen(remotes[i].url);
1957 		len += iremote.url_len;
1958 
1959 		wbuf = imsg_create(ibuf, GOT_IMSG_GITCONFIG_REMOTE, 0, 0, len);
1960 		if (wbuf == NULL)
1961 			return got_error_from_errno(
1962 			    "imsg_create GITCONFIG_REMOTE");
1963 
1964 		if (imsg_add(wbuf, &iremote, sizeof(iremote)) == -1) {
1965 			err = got_error_from_errno(
1966 			    "imsg_add GITCONFIG_REMOTE");
1967 			ibuf_free(wbuf);
1968 			return err;
1969 		}
1970 
1971 		if (imsg_add(wbuf, remotes[i].name, iremote.name_len) == -1) {
1972 			err = got_error_from_errno(
1973 			    "imsg_add GITCONFIG_REMOTE");
1974 			ibuf_free(wbuf);
1975 			return err;
1976 		}
1977 		if (imsg_add(wbuf, remotes[i].url, iremote.url_len) == -1) {
1978 			err = got_error_from_errno(
1979 			    "imsg_add GITCONFIG_REMOTE");
1980 			ibuf_free(wbuf);
1981 			return err;
1982 		}
1983 
1984 		wbuf->fd = -1;
1985 		imsg_close(ibuf, wbuf);
1986 		err = flush_imsg(ibuf);
1987 		if (err)
1988 			return err;
1989 	}
1990 
1991 	return NULL;
1992 }
1993 
1994 const struct got_error *
1995 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
1996     int *nremotes, struct imsgbuf *ibuf)
1997 {
1998 	const struct got_error *err = NULL;
1999 	struct imsg imsg;
2000 	size_t datalen;
2001 	struct got_imsg_remotes iremotes;
2002 	struct got_imsg_remote iremote;
2003 
2004 	*remotes = NULL;
2005 	*nremotes = 0;
2006 	iremotes.nremotes = 0;
2007 
2008 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
2009 	if (err)
2010 		return err;
2011 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2012 
2013 	switch (imsg.hdr.type) {
2014 	case GOT_IMSG_GITCONFIG_REMOTES:
2015 		if (datalen != sizeof(iremotes)) {
2016 			err = got_error(GOT_ERR_PRIVSEP_LEN);
2017 			break;
2018 		}
2019 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
2020 		if (iremotes.nremotes == 0) {
2021 			imsg_free(&imsg);
2022 			return NULL;
2023 		}
2024 		break;
2025 	default:
2026 		imsg_free(&imsg);
2027 		return got_error(GOT_ERR_PRIVSEP_MSG);
2028 	}
2029 
2030 	imsg_free(&imsg);
2031 
2032 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(**remotes));
2033 	if (*remotes == NULL)
2034 		return got_error_from_errno("recallocarray");
2035 
2036 	while (*nremotes < iremotes.nremotes) {
2037 		struct got_remote_repo *remote;
2038 	
2039 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
2040 		if (err)
2041 			break;
2042 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2043 
2044 		switch (imsg.hdr.type) {
2045 		case GOT_IMSG_GITCONFIG_REMOTE:
2046 			remote = &(*remotes)[*nremotes];
2047 			if (datalen < sizeof(iremote)) {
2048 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2049 				break;
2050 			}
2051 			memcpy(&iremote, imsg.data, sizeof(iremote));
2052 			if (iremote.name_len == 0 || iremote.url_len == 0 ||
2053 			    (sizeof(iremote) + iremote.name_len +
2054 			    iremote.url_len) > datalen) {
2055 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2056 				break;
2057 			}
2058 			remote->name = strndup(imsg.data + sizeof(iremote),
2059 			    iremote.name_len);
2060 			if (remote->name == NULL) {
2061 				err = got_error_from_errno("strndup");
2062 				break;
2063 			}
2064 			remote->url = strndup(imsg.data + sizeof(iremote) +
2065 			    iremote.name_len, iremote.url_len);
2066 			if (remote->url == NULL) {
2067 				err = got_error_from_errno("strndup");
2068 				free(remote->name);
2069 				break;
2070 			}
2071 			remote->mirror_references = iremote.mirror_references;
2072 			(*nremotes)++;
2073 			break;
2074 		default:
2075 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2076 			break;
2077 		}
2078 
2079 		imsg_free(&imsg);
2080 		if (err)
2081 			break;
2082 	}
2083 
2084 	if (err) {
2085 		int i;
2086 		for (i = 0; i < *nremotes; i++) {
2087 			free((*remotes)[i].name);
2088 			free((*remotes)[i].url);
2089 		}
2090 		free(*remotes);
2091 		*remotes = NULL;
2092 		*nremotes = 0;
2093 	}
2094 	return err;
2095 }
2096 
2097 const struct got_error *
2098 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
2099      struct got_object_id *id, int idx, const char *path)
2100 {
2101 	const struct got_error *err = NULL;
2102 	struct ibuf *wbuf;
2103 	size_t path_len = strlen(path) + 1;
2104 
2105 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
2106 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
2107 	if (wbuf == NULL)
2108 		return got_error_from_errno(
2109 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
2110 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
2111 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2112 		ibuf_free(wbuf);
2113 		return err;
2114 	}
2115 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1) {
2116 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2117 		ibuf_free(wbuf);
2118 		return err;
2119 	}
2120 	if (imsg_add(wbuf, path, path_len) == -1) {
2121 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2122 		ibuf_free(wbuf);
2123 		return err;
2124 	}
2125 
2126 	wbuf->fd = -1;
2127 	imsg_close(ibuf, wbuf);
2128 
2129 	return flush_imsg(ibuf);
2130 }
2131 
2132 const struct got_error *
2133 got_privsep_send_traversed_commits(struct got_object_id *commit_ids, 
2134     size_t ncommits, struct imsgbuf *ibuf)
2135 {
2136 	const struct got_error *err;
2137 	struct ibuf *wbuf;
2138 	int i;
2139 
2140 	wbuf = imsg_create(ibuf, GOT_IMSG_TRAVERSED_COMMITS, 0, 0,
2141 	    sizeof(struct got_imsg_traversed_commits) +
2142 	    ncommits * SHA1_DIGEST_LENGTH);
2143 	if (wbuf == NULL)
2144 		return got_error_from_errno("imsg_create TRAVERSED_COMMITS");
2145 
2146 	if (imsg_add(wbuf, &ncommits, sizeof(ncommits)) == -1) {
2147 		err = got_error_from_errno("imsg_add TRAVERSED_COMMITS");
2148 		ibuf_free(wbuf);
2149 		return err;
2150 	}
2151 	for (i = 0; i < ncommits; i++) {
2152 		struct got_object_id *id = &commit_ids[i];
2153 		if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
2154 			err = got_error_from_errno(
2155 			    "imsg_add TRAVERSED_COMMITS");
2156 			ibuf_free(wbuf);
2157 			return err;
2158 		}
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_recv_traversed_commits(struct got_commit_object **changed_commit,
2169     struct got_object_id **changed_commit_id,
2170     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
2171 {
2172 	const struct got_error *err = NULL;
2173 	struct imsg imsg;
2174 	struct got_imsg_traversed_commits *icommits;
2175 	size_t datalen;
2176 	int i, done = 0;
2177 
2178 	*changed_commit = NULL;
2179 	*changed_commit_id = NULL;
2180 
2181 	while (!done) {
2182 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2183 		if (err)
2184 			return err;
2185 
2186 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2187 		switch (imsg.hdr.type) {
2188 		case GOT_IMSG_TRAVERSED_COMMITS:
2189 			icommits = imsg.data;
2190 			if (datalen != sizeof(*icommits) +
2191 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
2192 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2193 				break;
2194 			}
2195 			for (i = 0; i < icommits->ncommits; i++) {
2196 				struct got_object_qid *qid;
2197 				uint8_t *sha1 = (uint8_t *)imsg.data +
2198 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
2199 				err = got_object_qid_alloc_partial(&qid);
2200 				if (err)
2201 					break;
2202 				memcpy(qid->id->sha1, sha1, SHA1_DIGEST_LENGTH);
2203 				SIMPLEQ_INSERT_TAIL(commit_ids, qid, entry);
2204 
2205 				/* The last commit may contain a change. */
2206 				if (i == icommits->ncommits - 1) {
2207 					*changed_commit_id =
2208 					    got_object_id_dup(qid->id);
2209 					if (*changed_commit_id == NULL) {
2210 						err = got_error_from_errno(
2211 						    "got_object_id_dup");
2212 						break;
2213 					}
2214 				}
2215 			}
2216 			break;
2217 		case GOT_IMSG_COMMIT:
2218 			if (*changed_commit_id == NULL) {
2219 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2220 				break;
2221 			}
2222 			err = get_commit_from_imsg(changed_commit, &imsg,
2223 			    datalen, ibuf);
2224 			break;
2225 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
2226 			done = 1;
2227 			break;
2228 		default:
2229 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2230 			break;
2231 		}
2232 
2233 		imsg_free(&imsg);
2234 		if (err)
2235 			break;
2236 	}
2237 
2238 	if (err)
2239 		got_object_id_queue_free(commit_ids);
2240 	return err;
2241 }
2242 
2243 const struct got_error *
2244 got_privsep_send_commit_traversal_done(struct imsgbuf *ibuf)
2245 {
2246 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_DONE, 0, 0, -1,
2247 	    NULL, 0) == -1)
2248 		return got_error_from_errno("imsg_compose TRAVERSAL_DONE");
2249 
2250 	return flush_imsg(ibuf);
2251 }
2252 
2253 const struct got_error *
2254 got_privsep_unveil_exec_helpers(void)
2255 {
2256 	const char *helpers[] = {
2257 	    GOT_PATH_PROG_READ_PACK,
2258 	    GOT_PATH_PROG_READ_OBJECT,
2259 	    GOT_PATH_PROG_READ_COMMIT,
2260 	    GOT_PATH_PROG_READ_TREE,
2261 	    GOT_PATH_PROG_READ_BLOB,
2262 	    GOT_PATH_PROG_READ_TAG,
2263 	    GOT_PATH_PROG_READ_GITCONFIG,
2264 	    GOT_PATH_PROG_FETCH_PACK,
2265 	    GOT_PATH_PROG_INDEX_PACK,
2266 	};
2267 	int i;
2268 
2269 	for (i = 0; i < nitems(helpers); i++) {
2270 		if (unveil(helpers[i], "x") == 0)
2271 			continue;
2272 		return got_error_from_errno2("unveil", helpers[i]);
2273 	}
2274 
2275 	return NULL;
2276 }
2277 
2278 void
2279 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
2280 {
2281 	if (close(imsg_fds[0]) != 0) {
2282 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2283 		_exit(1);
2284 	}
2285 
2286 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
2287 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2288 		_exit(1);
2289 	}
2290 	if (closefrom(GOT_IMSG_FD_CHILD + 1) == -1) {
2291 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2292 		_exit(1);
2293 	}
2294 
2295 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
2296 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
2297 		    strerror(errno));
2298 		_exit(1);
2299 	}
2300 }