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Date:: Sat Nov 23 21:03:29 2019 UTC
Message:: plug leaks in error paths of got_privsep_send_tree()
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1 /*
2  * Copyright (c) 2018, 2019 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include <sys/types.h>
18 #include <sys/queue.h>
19 #include <sys/uio.h>
20 #include <sys/syslimits.h>
21 #include <sys/wait.h>
22 
23 #include <stdio.h>
24 #include <stdlib.h>
25 #include <string.h>
26 #include <errno.h>
27 #include <stdint.h>
28 #include <poll.h>
29 #include <imsg.h>
30 #include <sha1.h>
31 #include <zlib.h>
32 #include <time.h>
33 
34 #include "got_object.h"
35 #include "got_error.h"
36 #include "got_path.h"
37 
38 #include "got_lib_sha1.h"
39 #include "got_lib_delta.h"
40 #include "got_lib_inflate.h"
41 #include "got_lib_object.h"
42 #include "got_lib_object_parse.h"
43 #include "got_lib_privsep.h"
44 #include "got_lib_pack.h"
45 
46 #ifndef MIN
47 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
48 #endif
49 
50 #ifndef nitems
51 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
52 #endif
53 
54 static const struct got_error *
55 poll_fd(int fd, int events, int timeout)
56 {
57 	struct pollfd pfd[1];
58 	int n;
59 
60 	pfd[0].fd = fd;
61 	pfd[0].events = events;
62 
63 	n = poll(pfd, 1, timeout);
64 	if (n == -1)
65 		return got_error_from_errno("poll");
66 	if (n == 0)
67 		return got_error(GOT_ERR_TIMEOUT);
68 	if (pfd[0].revents & (POLLERR | POLLNVAL))
69 		return got_error_from_errno("poll error");
70 	if (pfd[0].revents & (events | POLLHUP))
71 		return NULL;
72 
73 	return got_error(GOT_ERR_INTERRUPT);
74 }
75 
76 static const struct got_error *
77 read_imsg(struct imsgbuf *ibuf)
78 {
79 	const struct got_error *err;
80 	size_t n;
81 
82 	err = poll_fd(ibuf->fd, POLLIN, INFTIM);
83 	if (err)
84 		return err;
85 
86 	n = imsg_read(ibuf);
87 	if (n == -1) {
88 		if (errno == EAGAIN) /* Could be a file-descriptor leak. */
89 			return got_error(GOT_ERR_PRIVSEP_NO_FD);
90 		return got_error(GOT_ERR_PRIVSEP_READ);
91 	}
92 	if (n == 0)
93 		return got_error(GOT_ERR_PRIVSEP_PIPE);
94 
95 	return NULL;
96 }
97 
98 const struct got_error *
99 got_privsep_wait_for_child(pid_t pid)
100 {
101 	int child_status;
102 
103 	if (waitpid(pid, &child_status, 0) == -1)
104 		return got_error_from_errno("waitpid");
105 
106 	if (!WIFEXITED(child_status))
107 		return got_error(GOT_ERR_PRIVSEP_DIED);
108 
109 	if (WEXITSTATUS(child_status) != 0)
110 		return got_error(GOT_ERR_PRIVSEP_EXIT);
111 
112 	return NULL;
113 }
114 
115 static const struct got_error *
116 recv_imsg_error(struct imsg *imsg, size_t datalen)
117 {
118 	struct got_imsg_error *ierr;
119 
120 	if (datalen != sizeof(*ierr))
121 		return got_error(GOT_ERR_PRIVSEP_LEN);
122 
123 	ierr = imsg->data;
124 	if (ierr->code == GOT_ERR_ERRNO) {
125 		static struct got_error serr;
126 		serr.code = GOT_ERR_ERRNO;
127 		serr.msg = strerror(ierr->errno_code);
128 		return &serr;
129 	}
130 
131 	return got_error(ierr->code);
132 }
133 
134 const struct got_error *
135 got_privsep_recv_imsg(struct imsg *imsg, struct imsgbuf *ibuf,
136     size_t min_datalen)
137 {
138 	const struct got_error *err;
139 	ssize_t n;
140 
141 	n = imsg_get(ibuf, imsg);
142 	if (n == -1)
143 		return got_error_from_errno("imsg_get");
144 
145 	while (n == 0) {
146 		err = read_imsg(ibuf);
147 		if (err)
148 			return err;
149 		n = imsg_get(ibuf, imsg);
150 	}
151 
152 	if (imsg->hdr.len < IMSG_HEADER_SIZE + min_datalen)
153 		return got_error(GOT_ERR_PRIVSEP_LEN);
154 
155 	if (imsg->hdr.type == GOT_IMSG_ERROR) {
156 		size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
157 		return recv_imsg_error(imsg, datalen);
158 	}
159 
160 	return NULL;
161 }
162 
163 /* Attempt to send an error in an imsg. Complain on stderr as a last resort. */
164 void
165 got_privsep_send_error(struct imsgbuf *ibuf, const struct got_error *err)
166 {
167 	const struct got_error *poll_err;
168 	struct got_imsg_error ierr;
169 	int ret;
170 
171 	ierr.code = err->code;
172 	if (err->code == GOT_ERR_ERRNO)
173 		ierr.errno_code = errno;
174 	else
175 		ierr.errno_code = 0;
176 	ret = imsg_compose(ibuf, GOT_IMSG_ERROR, 0, 0, -1, &ierr, sizeof(ierr));
177 	if (ret == -1) {
178 		fprintf(stderr, "%s: error %d \"%s\": imsg_compose: %s\n",
179 		    getprogname(), err->code, err->msg, strerror(errno));
180 		return;
181 	}
182 
183 	poll_err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
184 	if (poll_err) {
185 		fprintf(stderr, "%s: error %d \"%s\": poll: %s\n",
186 		    getprogname(), err->code, err->msg, poll_err->msg);
187 		return;
188 	}
189 
190 	ret = imsg_flush(ibuf);
191 	if (ret == -1) {
192 		fprintf(stderr, "%s: error %d \"%s\": imsg_flush: %s\n",
193 		    getprogname(), err->code, err->msg, strerror(errno));
194 		return;
195 	}
196 }
197 
198 static const struct got_error *
199 flush_imsg(struct imsgbuf *ibuf)
200 {
201 	const struct got_error *err;
202 
203 	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
204 	if (err)
205 		return err;
206 
207 	if (imsg_flush(ibuf) == -1)
208 		return got_error_from_errno("imsg_flush");
209 
210 	return NULL;
211 }
212 
213 const struct got_error *
214 got_privsep_send_stop(int fd)
215 {
216 	const struct got_error *err = NULL;
217 	struct imsgbuf ibuf;
218 
219 	imsg_init(&ibuf, fd);
220 
221 	if (imsg_compose(&ibuf, GOT_IMSG_STOP, 0, 0, -1, NULL, 0) == -1)
222 		return got_error_from_errno("imsg_compose STOP");
223 
224 	err = flush_imsg(&ibuf);
225 	imsg_clear(&ibuf);
226 	return err;
227 }
228 
229 const struct got_error *
230 got_privsep_send_obj_req(struct imsgbuf *ibuf, int fd)
231 {
232 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT_REQUEST, 0, 0, fd, NULL, 0)
233 	    == -1)
234 		return got_error_from_errno("imsg_compose OBJECT_REQUEST");
235 
236 	return flush_imsg(ibuf);
237 }
238 
239 const struct got_error *
240 got_privsep_send_commit_req(struct imsgbuf *ibuf, int fd,
241     struct got_object_id *id, int pack_idx)
242 {
243 	const struct got_error *err = NULL;
244 	struct got_imsg_packed_object iobj, *iobjp;
245 	size_t len;
246 
247 	if (id) { /* commit is packed */
248 		iobj.idx = pack_idx;
249 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
250 		iobjp = &iobj;
251 		len = sizeof(iobj);
252 	} else {
253 		iobjp = NULL;
254 		len = 0;
255 	}
256 
257 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_REQUEST, 0, 0, fd, iobjp, len)
258 	    == -1) {
259 		err = got_error_from_errno("imsg_compose COMMIT_REQUEST");
260 		close(fd);
261 		return err;
262 	}
263 
264 	return flush_imsg(ibuf);
265 }
266 
267 const struct got_error *
268 got_privsep_send_tree_req(struct imsgbuf *ibuf, int fd,
269     struct got_object_id *id, int pack_idx)
270 {
271 	const struct got_error *err = NULL;
272 	struct ibuf *wbuf;
273 	size_t len = id ? sizeof(struct got_imsg_packed_object) : 0;
274 
275 	wbuf = imsg_create(ibuf, GOT_IMSG_TREE_REQUEST, 0, 0, len);
276 	if (wbuf == NULL)
277 		return got_error_from_errno("imsg_create TREE_REQUEST");
278 
279 	if (id) { /* tree is packed */
280 		if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
281 			err = got_error_from_errno("imsg_add TREE_ENTRY");
282 			ibuf_free(wbuf);
283 			return err;
284 		}
285 
286 		if (imsg_add(wbuf, &pack_idx, sizeof(pack_idx)) == -1) {
287 			err = got_error_from_errno("imsg_add TREE_ENTRY");
288 			ibuf_free(wbuf);
289 			return err;
290 		}
291 	}
292 
293 	wbuf->fd = fd;
294 	imsg_close(ibuf, wbuf);
295 
296 	return flush_imsg(ibuf);
297 }
298 
299 const struct got_error *
300 got_privsep_send_tag_req(struct imsgbuf *ibuf, int fd,
301     struct got_object_id *id, int pack_idx)
302 {
303 	struct got_imsg_packed_object iobj, *iobjp;
304 	size_t len;
305 
306 	if (id) { /* tag is packed */
307 		iobj.idx = pack_idx;
308 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
309 		iobjp = &iobj;
310 		len = sizeof(iobj);
311 	} else {
312 		iobjp = NULL;
313 		len = 0;
314 	}
315 
316 	if (imsg_compose(ibuf, GOT_IMSG_TAG_REQUEST, 0, 0, fd, iobjp, len)
317 	    == -1)
318 		return got_error_from_errno("imsg_compose TAG_REQUEST");
319 
320 	return flush_imsg(ibuf);
321 }
322 
323 const struct got_error *
324 got_privsep_send_blob_req(struct imsgbuf *ibuf, int infd,
325     struct got_object_id *id, int pack_idx)
326 {
327 	const struct got_error *err = NULL;
328 	struct got_imsg_packed_object iobj, *iobjp;
329 	size_t len;
330 
331 	if (id) { /* blob is packed */
332 		iobj.idx = pack_idx;
333 		memcpy(iobj.id, id->sha1, sizeof(iobj.id));
334 		iobjp = &iobj;
335 		len = sizeof(iobj);
336 	} else {
337 		iobjp = NULL;
338 		len = 0;
339 	}
340 
341 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_REQUEST, 0, 0, infd, iobjp, len)
342 	    == -1) {
343 		err = got_error_from_errno("imsg_compose BLOB_REQUEST");
344 		close(infd);
345 		return err;
346 	}
347 
348 	return flush_imsg(ibuf);
349 }
350 
351 const struct got_error *
352 got_privsep_send_blob_outfd(struct imsgbuf *ibuf, int outfd)
353 {
354 	const struct got_error *err = NULL;
355 
356 	if (imsg_compose(ibuf, GOT_IMSG_BLOB_OUTFD, 0, 0, outfd, NULL, 0)
357 	    == -1) {
358 		err = got_error_from_errno("imsg_compose BLOB_OUTFD");
359 		close(outfd);
360 		return err;
361 	}
362 
363 	return flush_imsg(ibuf);
364 }
365 
366 const struct got_error *
367 got_privsep_send_tmpfd(struct imsgbuf *ibuf, int fd)
368 {
369 	const struct got_error *err = NULL;
370 
371 	if (imsg_compose(ibuf, GOT_IMSG_TMPFD, 0, 0, fd, NULL, 0)
372 	    == -1) {
373 		err = got_error_from_errno("imsg_compose TMPFD");
374 		close(fd);
375 		return err;
376 	}
377 
378 	return flush_imsg(ibuf);
379 }
380 
381 const struct got_error *
382 got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj)
383 {
384 	struct got_imsg_object iobj;
385 
386 	memcpy(iobj.id, obj->id.sha1, sizeof(iobj.id));
387 	iobj.type = obj->type;
388 	iobj.flags = obj->flags;
389 	iobj.hdrlen = obj->hdrlen;
390 	iobj.size = obj->size;
391 	if (iobj.flags & GOT_OBJ_FLAG_PACKED) {
392 		iobj.pack_offset = obj->pack_offset;
393 		iobj.pack_idx = obj->pack_idx;
394 	}
395 
396 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
397 	    == -1)
398 		return got_error_from_errno("imsg_compose OBJECT");
399 
400 	return flush_imsg(ibuf);
401 }
402 
403 const struct got_error *
404 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
405     struct imsgbuf *ibuf)
406 {
407 	const struct got_error *err = NULL;
408 	struct got_imsg_object *iobj;
409 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
410 
411 	if (datalen != sizeof(*iobj))
412 		return got_error(GOT_ERR_PRIVSEP_LEN);
413 	iobj = imsg->data;
414 
415 	*obj = calloc(1, sizeof(**obj));
416 	if (*obj == NULL)
417 		return got_error_from_errno("calloc");
418 
419 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
420 	(*obj)->type = iobj->type;
421 	(*obj)->flags = iobj->flags;
422 	(*obj)->hdrlen = iobj->hdrlen;
423 	(*obj)->size = iobj->size;
424 	/* path_packfile is handled by caller */
425 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
426 		(*obj)->pack_offset = iobj->pack_offset;
427 		(*obj)->pack_idx = iobj->pack_idx;
428 	}
429 
430 	return err;
431 }
432 
433 const struct got_error *
434 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
435 {
436 	const struct got_error *err = NULL;
437 	struct imsg imsg;
438 	const size_t min_datalen =
439 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
440 
441 	*obj = NULL;
442 
443 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
444 	if (err)
445 		return err;
446 
447 	switch (imsg.hdr.type) {
448 	case GOT_IMSG_OBJECT:
449 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
450 		break;
451 	default:
452 		err = got_error(GOT_ERR_PRIVSEP_MSG);
453 		break;
454 	}
455 
456 	imsg_free(&imsg);
457 
458 	return err;
459 }
460 
461 static const struct got_error *
462 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
463     size_t logmsg_len)
464 {
465 	const struct got_error *err = NULL;
466 	size_t offset, remain;
467 
468 	offset = 0;
469 	remain = logmsg_len;
470 	while (remain > 0) {
471 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
472 
473 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
474 		    commit->logmsg + offset, n) == -1) {
475 			err = got_error_from_errno("imsg_compose "
476 			    "COMMIT_LOGMSG");
477 			break;
478 		}
479 
480 		err = flush_imsg(ibuf);
481 		if (err)
482 			break;
483 
484 		offset += n;
485 		remain -= n;
486 	}
487 
488 	return err;
489 }
490 
491 const struct got_error *
492 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
493 {
494 	const struct got_error *err = NULL;
495 	struct got_imsg_commit_object *icommit;
496 	uint8_t *buf;
497 	size_t len, total;
498 	struct got_object_qid *qid;
499 	size_t author_len = strlen(commit->author);
500 	size_t committer_len = strlen(commit->committer);
501 	size_t logmsg_len = strlen(commit->logmsg);
502 
503 	total = sizeof(*icommit) + author_len + committer_len +
504 	    commit->nparents * SHA1_DIGEST_LENGTH;
505 
506 	buf = malloc(total);
507 	if (buf == NULL)
508 		return got_error_from_errno("malloc");
509 
510 	icommit = (struct got_imsg_commit_object *)buf;
511 	memcpy(icommit->tree_id, commit->tree_id->sha1,
512 	    sizeof(icommit->tree_id));
513 	icommit->author_len = author_len;
514 	icommit->author_time = commit->author_time;
515 	icommit->author_gmtoff = commit->author_gmtoff;
516 	icommit->committer_len = committer_len;
517 	icommit->committer_time = commit->committer_time;
518 	icommit->committer_gmtoff = commit->committer_gmtoff;
519 	icommit->logmsg_len = logmsg_len;
520 	icommit->nparents = commit->nparents;
521 
522 	len = sizeof(*icommit);
523 	memcpy(buf + len, commit->author, author_len);
524 	len += author_len;
525 	memcpy(buf + len, commit->committer, committer_len);
526 	len += committer_len;
527 	SIMPLEQ_FOREACH(qid, &commit->parent_ids, entry) {
528 		memcpy(buf + len, qid->id, SHA1_DIGEST_LENGTH);
529 		len += SHA1_DIGEST_LENGTH;
530 	}
531 
532 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
533 		err = got_error_from_errno("imsg_compose COMMIT");
534 		goto done;
535 	}
536 
537 	if (logmsg_len == 0 ||
538 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
539 		err = flush_imsg(ibuf);
540 		if (err)
541 			goto done;
542 	}
543 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
544 done:
545 	free(buf);
546 	return err;
547 }
548 
549 const struct got_error *
550 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
551 {
552 	const struct got_error *err = NULL;
553 	struct imsg imsg;
554 	struct got_imsg_commit_object *icommit;
555 	size_t len, datalen;
556 	int i;
557 	const size_t min_datalen =
558 	    MIN(sizeof(struct got_imsg_error),
559 	    sizeof(struct got_imsg_commit_object));
560 
561 	*commit = NULL;
562 
563 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
564 	if (err)
565 		return err;
566 
567 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
568 	len = 0;
569 
570 	switch (imsg.hdr.type) {
571 	case GOT_IMSG_COMMIT:
572 		if (datalen < sizeof(*icommit)) {
573 			err = got_error(GOT_ERR_PRIVSEP_LEN);
574 			break;
575 		}
576 		icommit = imsg.data;
577 		if (datalen != sizeof(*icommit) + icommit->author_len +
578 		    icommit->committer_len +
579 		    icommit->nparents * SHA1_DIGEST_LENGTH) {
580 			err = got_error(GOT_ERR_PRIVSEP_LEN);
581 			break;
582 		}
583 		if (icommit->nparents < 0) {
584 			err = got_error(GOT_ERR_PRIVSEP_LEN);
585 			break;
586 		}
587 		len += sizeof(*icommit);
588 
589 		*commit = got_object_commit_alloc_partial();
590 		if (*commit == NULL) {
591 			err = got_error_from_errno(
592 			    "got_object_commit_alloc_partial");
593 			break;
594 		}
595 
596 		memcpy((*commit)->tree_id->sha1, icommit->tree_id,
597 		    SHA1_DIGEST_LENGTH);
598 		(*commit)->author_time = icommit->author_time;
599 		(*commit)->author_gmtoff = icommit->author_gmtoff;
600 		(*commit)->committer_time = icommit->committer_time;
601 		(*commit)->committer_gmtoff = icommit->committer_gmtoff;
602 
603 		if (icommit->author_len == 0) {
604 			(*commit)->author = strdup("");
605 			if ((*commit)->author == NULL) {
606 				err = got_error_from_errno("strdup");
607 				break;
608 			}
609 		} else {
610 			(*commit)->author = malloc(icommit->author_len + 1);
611 			if ((*commit)->author == NULL) {
612 				err = got_error_from_errno("malloc");
613 				break;
614 			}
615 			memcpy((*commit)->author, imsg.data + len,
616 			    icommit->author_len);
617 			(*commit)->author[icommit->author_len] = '\0';
618 		}
619 		len += icommit->author_len;
620 
621 		if (icommit->committer_len == 0) {
622 			(*commit)->committer = strdup("");
623 			if ((*commit)->committer == NULL) {
624 				err = got_error_from_errno("strdup");
625 				break;
626 			}
627 		} else {
628 			(*commit)->committer =
629 			    malloc(icommit->committer_len + 1);
630 			if ((*commit)->committer == NULL) {
631 				err = got_error_from_errno("malloc");
632 				break;
633 			}
634 			memcpy((*commit)->committer, imsg.data + len,
635 			    icommit->committer_len);
636 			(*commit)->committer[icommit->committer_len] = '\0';
637 		}
638 		len += icommit->committer_len;
639 
640 		if (icommit->logmsg_len == 0) {
641 			(*commit)->logmsg = strdup("");
642 			if ((*commit)->logmsg == NULL) {
643 				err = got_error_from_errno("strdup");
644 				break;
645 			}
646 		} else {
647 			size_t offset = 0, remain = icommit->logmsg_len;
648 
649 			(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
650 			if ((*commit)->logmsg == NULL) {
651 				err = got_error_from_errno("malloc");
652 				break;
653 			}
654 			while (remain > 0) {
655 				struct imsg imsg_log;
656 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
657 				    remain);
658 
659 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
660 				if (err)
661 					return err;
662 
663 				if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG)
664 					return got_error(GOT_ERR_PRIVSEP_MSG);
665 
666 				memcpy((*commit)->logmsg + offset,
667 				    imsg_log.data, n);
668 				imsg_free(&imsg_log);
669 				offset += n;
670 				remain -= n;
671 			}
672 			(*commit)->logmsg[icommit->logmsg_len] = '\0';
673 		}
674 
675 		for (i = 0; i < icommit->nparents; i++) {
676 			struct got_object_qid *qid;
677 
678 			err = got_object_qid_alloc_partial(&qid);
679 			if (err)
680 				break;
681 			memcpy(qid->id, imsg.data + len +
682 			    i * SHA1_DIGEST_LENGTH, sizeof(*qid->id));
683 			SIMPLEQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
684 			(*commit)->nparents++;
685 		}
686 		break;
687 	default:
688 		err = got_error(GOT_ERR_PRIVSEP_MSG);
689 		break;
690 	}
691 
692 	imsg_free(&imsg);
693 
694 	return err;
695 }
696 
697 const struct got_error *
698 got_privsep_send_tree(struct imsgbuf *ibuf, struct got_pathlist_head *entries,
699     int nentries)
700 {
701 	const struct got_error *err = NULL;
702 	struct got_imsg_tree_object itree;
703 	struct got_pathlist_entry *pe;
704 	size_t totlen;
705 	int nimsg; /* number of imsg queued in ibuf */
706 
707 	itree.nentries = nentries;
708 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
709 	    == -1)
710 		return got_error_from_errno("imsg_compose TREE");
711 
712 	totlen = sizeof(itree);
713 	nimsg = 1;
714 	TAILQ_FOREACH(pe, entries, entry) {
715 		const char *name = pe->path;
716 		struct got_parsed_tree_entry *pte = pe->data;
717 		struct ibuf *wbuf;
718 		size_t namelen = strlen(name);
719 		size_t len = sizeof(struct got_imsg_tree_object) + namelen;
720 
721 		if (len > MAX_IMSGSIZE)
722 			return got_error(GOT_ERR_NO_SPACE);
723 
724 		nimsg++;
725 		if (totlen + len >= MAX_IMSGSIZE - (IMSG_HEADER_SIZE * nimsg)) {
726 			err = flush_imsg(ibuf);
727 			if (err)
728 				return err;
729 			nimsg = 0;
730 		}
731 
732 		wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRY, 0, 0, len);
733 		if (wbuf == NULL)
734 			return got_error_from_errno("imsg_create TREE_ENTRY");
735 
736 		/* Keep in sync with struct got_imsg_tree_object definition! */
737 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1) {
738 			err = got_error_from_errno("imsg_add TREE_ENTRY");
739 			ibuf_free(wbuf);
740 			return err;
741 		}
742 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1) {
743 			err = got_error_from_errno("imsg_add TREE_ENTRY");
744 			ibuf_free(wbuf);
745 			return err;
746 		}
747 
748 		if (imsg_add(wbuf, name, namelen) == -1) {
749 			err = got_error_from_errno("imsg_add TREE_ENTRY");
750 			ibuf_free(wbuf);
751 			return err;
752 		}
753 
754 		wbuf->fd = -1;
755 		imsg_close(ibuf, wbuf);
756 
757 		totlen += len;
758 	}
759 
760 	return flush_imsg(ibuf);
761 }
762 
763 const struct got_error *
764 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
765 {
766 	const struct got_error *err = NULL;
767 	const size_t min_datalen =
768 	    MIN(sizeof(struct got_imsg_error),
769 	    sizeof(struct got_imsg_tree_object));
770 	struct got_imsg_tree_object *itree;
771 	int nentries = 0;
772 
773 	*tree = NULL;
774 get_more:
775 	err = read_imsg(ibuf);
776 	if (err)
777 		goto done;
778 
779 	for (;;) {
780 		struct imsg imsg;
781 		size_t n;
782 		size_t datalen;
783 		struct got_imsg_tree_entry *ite;
784 		struct got_tree_entry *te = NULL;
785 
786 		n = imsg_get(ibuf, &imsg);
787 		if (n == 0) {
788 			if (*tree && (*tree)->entries.nentries != nentries)
789 				goto get_more;
790 			break;
791 		}
792 
793 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen)
794 			return got_error(GOT_ERR_PRIVSEP_LEN);
795 
796 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
797 
798 		switch (imsg.hdr.type) {
799 		case GOT_IMSG_ERROR:
800 			err = recv_imsg_error(&imsg, datalen);
801 			break;
802 		case GOT_IMSG_TREE:
803 			/* This message should only appear once. */
804 			if (*tree != NULL) {
805 				err = got_error(GOT_ERR_PRIVSEP_MSG);
806 				break;
807 			}
808 			if (datalen != sizeof(*itree)) {
809 				err = got_error(GOT_ERR_PRIVSEP_LEN);
810 				break;
811 			}
812 			itree = imsg.data;
813 			*tree = malloc(sizeof(**tree));
814 			if (*tree == NULL) {
815 				err = got_error_from_errno("malloc");
816 				break;
817 			}
818 			(*tree)->entries.nentries = itree->nentries;
819 			SIMPLEQ_INIT(&(*tree)->entries.head);
820 			(*tree)->refcnt = 0;
821 			break;
822 		case GOT_IMSG_TREE_ENTRY:
823 			/* This message should be preceeded by GOT_IMSG_TREE. */
824 			if (*tree == NULL) {
825 				err = got_error(GOT_ERR_PRIVSEP_MSG);
826 				break;
827 			}
828 			if (datalen < sizeof(*ite) || datalen > MAX_IMSGSIZE) {
829 				err = got_error(GOT_ERR_PRIVSEP_LEN);
830 				break;
831 			}
832 
833 			/* Remaining data contains the entry's name. */
834 			datalen -= sizeof(*ite);
835 			if (datalen == 0 || datalen > MAX_IMSGSIZE) {
836 				err = got_error(GOT_ERR_PRIVSEP_LEN);
837 				break;
838 			}
839 			ite = imsg.data;
840 
841 			te = got_alloc_tree_entry_partial();
842 			if (te == NULL) {
843 				err = got_error_from_errno(
844 				    "got_alloc_tree_entry_partial");
845 				break;
846 			}
847 			te->name = malloc(datalen + 1);
848 			if (te->name == NULL) {
849 				free(te);
850 				err = got_error_from_errno("malloc");
851 				break;
852 			}
853 			memcpy(te->name, imsg.data + sizeof(*ite), datalen);
854 			te->name[datalen] = '\0';
855 
856 			memcpy(te->id->sha1, ite->id, SHA1_DIGEST_LENGTH);
857 			te->mode = ite->mode;
858 			SIMPLEQ_INSERT_TAIL(&(*tree)->entries.head, te, entry);
859 			nentries++;
860 			break;
861 		default:
862 			err = got_error(GOT_ERR_PRIVSEP_MSG);
863 			break;
864 		}
865 
866 		imsg_free(&imsg);
867 	}
868 done:
869 	if (*tree && (*tree)->entries.nentries != nentries) {
870 		if (err == NULL)
871 			err = got_error(GOT_ERR_PRIVSEP_LEN);
872 		got_object_tree_close(*tree);
873 		*tree = NULL;
874 	}
875 
876 	return err;
877 }
878 
879 const struct got_error *
880 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
881     const uint8_t *data)
882 {
883 	struct got_imsg_blob iblob;
884 
885 	iblob.size = size;
886 	iblob.hdrlen = hdrlen;
887 
888 	if (data) {
889 		uint8_t *buf;
890 
891 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
892 			return got_error(GOT_ERR_NO_SPACE);
893 
894 		buf = malloc(sizeof(iblob) + size);
895 		if (buf == NULL)
896 			return got_error_from_errno("malloc");
897 
898 		memcpy(buf, &iblob, sizeof(iblob));
899 		memcpy(buf + sizeof(iblob), data, size);
900 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
901 		   sizeof(iblob) + size) == -1) {
902 			free(buf);
903 			return got_error_from_errno("imsg_compose BLOB");
904 		}
905 		free(buf);
906 	} else {
907 		/* Data has already been written to file descriptor. */
908 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
909 		    sizeof(iblob)) == -1)
910 			return got_error_from_errno("imsg_compose BLOB");
911 	}
912 
913 
914 	return flush_imsg(ibuf);
915 }
916 
917 const struct got_error *
918 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
919     struct imsgbuf *ibuf)
920 {
921 	const struct got_error *err = NULL;
922 	struct imsg imsg;
923 	struct got_imsg_blob *iblob;
924 	size_t datalen;
925 
926 	*outbuf = NULL;
927 
928 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
929 	if (err)
930 		return err;
931 
932 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
933 
934 	switch (imsg.hdr.type) {
935 	case GOT_IMSG_BLOB:
936 		if (datalen < sizeof(*iblob)) {
937 			err = got_error(GOT_ERR_PRIVSEP_LEN);
938 			break;
939 		}
940 		iblob = imsg.data;
941 		*size = iblob->size;
942 		*hdrlen = iblob->hdrlen;
943 
944 		if (datalen == sizeof(*iblob)) {
945 			/* Data has been written to file descriptor. */
946 			break;
947 		}
948 
949 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX) {
950 			err = got_error(GOT_ERR_PRIVSEP_LEN);
951 			break;
952 		}
953 
954 		*outbuf = malloc(*size);
955 		if (*outbuf == NULL) {
956 			err = got_error_from_errno("malloc");
957 			break;
958 		}
959 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
960 		break;
961 	default:
962 		err = got_error(GOT_ERR_PRIVSEP_MSG);
963 		break;
964 	}
965 
966 	imsg_free(&imsg);
967 
968 	return err;
969 }
970 
971 static const struct got_error *
972 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
973 {
974 	const struct got_error *err = NULL;
975 	size_t offset, remain;
976 
977 	offset = 0;
978 	remain = tagmsg_len;
979 	while (remain > 0) {
980 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
981 
982 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
983 		    tag->tagmsg + offset, n) == -1) {
984 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
985 			break;
986 		}
987 
988 		err = flush_imsg(ibuf);
989 		if (err)
990 			break;
991 
992 		offset += n;
993 		remain -= n;
994 	}
995 
996 	return err;
997 }
998 
999 const struct got_error *
1000 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1001 {
1002 	const struct got_error *err = NULL;
1003 	struct got_imsg_tag_object *itag;
1004 	uint8_t *buf;
1005 	size_t len, total;
1006 	size_t tag_len = strlen(tag->tag);
1007 	size_t tagger_len = strlen(tag->tagger);
1008 	size_t tagmsg_len = strlen(tag->tagmsg);
1009 
1010 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1011 
1012 	buf = malloc(total);
1013 	if (buf == NULL)
1014 		return got_error_from_errno("malloc");
1015 
1016 	itag = (struct got_imsg_tag_object *)buf;
1017 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1018 	itag->obj_type = tag->obj_type;
1019 	itag->tag_len = tag_len;
1020 	itag->tagger_len = tagger_len;
1021 	itag->tagger_time = tag->tagger_time;
1022 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1023 	itag->tagmsg_len = tagmsg_len;
1024 
1025 	len = sizeof(*itag);
1026 	memcpy(buf + len, tag->tag, tag_len);
1027 	len += tag_len;
1028 	memcpy(buf + len, tag->tagger, tagger_len);
1029 	len += tagger_len;
1030 
1031 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1032 		err = got_error_from_errno("imsg_compose TAG");
1033 		goto done;
1034 	}
1035 
1036 	if (tagmsg_len == 0 ||
1037 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1038 		err = flush_imsg(ibuf);
1039 		if (err)
1040 			goto done;
1041 	}
1042 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1043 done:
1044 	free(buf);
1045 	return err;
1046 }
1047 
1048 const struct got_error *
1049 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1050 {
1051 	const struct got_error *err = NULL;
1052 	struct imsg imsg;
1053 	struct got_imsg_tag_object *itag;
1054 	size_t len, datalen;
1055 	const size_t min_datalen =
1056 	    MIN(sizeof(struct got_imsg_error),
1057 	    sizeof(struct got_imsg_tag_object));
1058 
1059 	*tag = NULL;
1060 
1061 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1062 	if (err)
1063 		return err;
1064 
1065 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1066 	len = 0;
1067 
1068 	switch (imsg.hdr.type) {
1069 	case GOT_IMSG_TAG:
1070 		if (datalen < sizeof(*itag)) {
1071 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1072 			break;
1073 		}
1074 		itag = imsg.data;
1075 		if (datalen != sizeof(*itag) + itag->tag_len +
1076 		    itag->tagger_len) {
1077 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1078 			break;
1079 		}
1080 		len += sizeof(*itag);
1081 
1082 		*tag = calloc(1, sizeof(**tag));
1083 		if (*tag == NULL) {
1084 			err = got_error_from_errno("calloc");
1085 			break;
1086 		}
1087 
1088 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1089 
1090 		if (itag->tag_len == 0) {
1091 			(*tag)->tag = strdup("");
1092 			if ((*tag)->tag == NULL) {
1093 				err = got_error_from_errno("strdup");
1094 				break;
1095 			}
1096 		} else {
1097 			(*tag)->tag = malloc(itag->tag_len + 1);
1098 			if ((*tag)->tag == NULL) {
1099 				err = got_error_from_errno("malloc");
1100 				break;
1101 			}
1102 			memcpy((*tag)->tag, imsg.data + len,
1103 			    itag->tag_len);
1104 			(*tag)->tag[itag->tag_len] = '\0';
1105 		}
1106 		len += itag->tag_len;
1107 
1108 		(*tag)->obj_type = itag->obj_type;
1109 		(*tag)->tagger_time = itag->tagger_time;
1110 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1111 
1112 		if (itag->tagger_len == 0) {
1113 			(*tag)->tagger = strdup("");
1114 			if ((*tag)->tagger == NULL) {
1115 				err = got_error_from_errno("strdup");
1116 				break;
1117 			}
1118 		} else {
1119 			(*tag)->tagger = malloc(itag->tagger_len + 1);
1120 			if ((*tag)->tagger == NULL) {
1121 				err = got_error_from_errno("malloc");
1122 				break;
1123 			}
1124 			memcpy((*tag)->tagger, imsg.data + len,
1125 			    itag->tagger_len);
1126 			(*tag)->tagger[itag->tagger_len] = '\0';
1127 		}
1128 		len += itag->tagger_len;
1129 
1130 		if (itag->tagmsg_len == 0) {
1131 			(*tag)->tagmsg = strdup("");
1132 			if ((*tag)->tagmsg == NULL) {
1133 				err = got_error_from_errno("strdup");
1134 				break;
1135 			}
1136 		} else {
1137 			size_t offset = 0, remain = itag->tagmsg_len;
1138 
1139 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1140 			if ((*tag)->tagmsg == NULL) {
1141 				err = got_error_from_errno("malloc");
1142 				break;
1143 			}
1144 			while (remain > 0) {
1145 				struct imsg imsg_log;
1146 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1147 				    remain);
1148 
1149 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1150 				if (err)
1151 					return err;
1152 
1153 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1154 					return got_error(GOT_ERR_PRIVSEP_MSG);
1155 
1156 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1157 				    n);
1158 				imsg_free(&imsg_log);
1159 				offset += n;
1160 				remain -= n;
1161 			}
1162 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1163 		}
1164 
1165 		break;
1166 	default:
1167 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1168 		break;
1169 	}
1170 
1171 	imsg_free(&imsg);
1172 
1173 	return err;
1174 }
1175 
1176 const struct got_error *
1177 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1178     struct got_packidx *packidx)
1179 {
1180 	const struct got_error *err = NULL;
1181 	struct got_imsg_packidx ipackidx;
1182 	struct got_imsg_pack ipack;
1183 	int fd;
1184 
1185 	ipackidx.len = packidx->len;
1186 	fd = dup(packidx->fd);
1187 	if (fd == -1)
1188 		return got_error_from_errno("dup");
1189 
1190 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
1191 	    sizeof(ipackidx)) == -1) {
1192 		err = got_error_from_errno("imsg_compose PACKIDX");
1193 		close(fd);
1194 		return err;
1195 	}
1196 
1197 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
1198 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
1199 		return got_error(GOT_ERR_NO_SPACE);
1200 	ipack.filesize = pack->filesize;
1201 
1202 	fd = dup(pack->fd);
1203 	if (fd == -1)
1204 		return got_error_from_errno("dup");
1205 
1206 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
1207 	    == -1) {
1208 		err = got_error_from_errno("imsg_compose PACK");
1209 		close(fd);
1210 		return err;
1211 	}
1212 
1213 	return flush_imsg(ibuf);
1214 }
1215 
1216 const struct got_error *
1217 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
1218     struct got_object_id *id)
1219 {
1220 	struct got_imsg_packed_object iobj;
1221 
1222 	iobj.idx = idx;
1223 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
1224 
1225 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
1226 	    &iobj, sizeof(iobj)) == -1)
1227 		return got_error_from_errno("imsg_compose "
1228 		    "PACKED_OBJECT_REQUEST");
1229 
1230 	return flush_imsg(ibuf);
1231 }
1232 
1233 const struct got_error *
1234 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
1235 {
1236 	const struct got_error *err = NULL;
1237 
1238 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
1239 	    NULL, 0) == -1) {
1240 		err = got_error_from_errno("imsg_compose "
1241 		    "GITCONFIG_PARSE_REQUEST");
1242 		close(fd);
1243 		return err;
1244 	}
1245 
1246 	return flush_imsg(ibuf);
1247 }
1248 
1249 const struct got_error *
1250 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
1251 {
1252 	if (imsg_compose(ibuf,
1253 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
1254 	    NULL, 0) == -1)
1255 		return got_error_from_errno("imsg_compose "
1256 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
1257 
1258 	return flush_imsg(ibuf);
1259 }
1260 
1261 const struct got_error *
1262 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
1263 {
1264 	if (imsg_compose(ibuf,
1265 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
1266 		return got_error_from_errno("imsg_compose "
1267 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
1268 
1269 	return flush_imsg(ibuf);
1270 }
1271 
1272 const struct got_error *
1273 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
1274 {
1275 	if (imsg_compose(ibuf,
1276 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
1277 		return got_error_from_errno("imsg_compose "
1278 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
1279 
1280 	return flush_imsg(ibuf);
1281 }
1282 
1283 const struct got_error *
1284 got_privsep_send_gitconfig_str(struct imsgbuf *ibuf, const char *value)
1285 {
1286 	size_t len = value ? strlen(value) + 1 : 0;
1287 
1288 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_STR_VAL, 0, 0, -1,
1289 	    value, len) == -1)
1290 		return got_error_from_errno("imsg_compose GITCONFIG_STR_VAL");
1291 
1292 	return flush_imsg(ibuf);
1293 }
1294 
1295 const struct got_error *
1296 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
1297 {
1298 	const struct got_error *err = NULL;
1299 	struct imsg imsg;
1300 	size_t datalen;
1301 	const size_t min_datalen = 0;
1302 
1303 	*str = NULL;
1304 
1305 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1306 	if (err)
1307 		return err;
1308 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1309 
1310 	switch (imsg.hdr.type) {
1311 	case GOT_IMSG_GITCONFIG_STR_VAL:
1312 		if (datalen == 0)
1313 			break;
1314 		*str = malloc(datalen);
1315 		if (*str == NULL) {
1316 			err = got_error_from_errno("malloc");
1317 			break;
1318 		}
1319 		if (strlcpy(*str, imsg.data, datalen) >= datalen)
1320 			err = got_error(GOT_ERR_NO_SPACE);
1321 		break;
1322 	default:
1323 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1324 		break;
1325 	}
1326 
1327 	imsg_free(&imsg);
1328 	return err;
1329 }
1330 
1331 const struct got_error *
1332 got_privsep_send_gitconfig_int(struct imsgbuf *ibuf, int value)
1333 {
1334 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_INT_VAL, 0, 0, -1,
1335 	    &value, sizeof(value)) == -1)
1336 		return got_error_from_errno("imsg_compose GITCONFIG_INT_VAL");
1337 
1338 	return flush_imsg(ibuf);
1339 }
1340 
1341 const struct got_error *
1342 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
1343 {
1344 	const struct got_error *err = NULL;
1345 	struct imsg imsg;
1346 	size_t datalen;
1347 	const size_t min_datalen =
1348 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
1349 
1350 	*val = 0;
1351 
1352 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1353 	if (err)
1354 		return err;
1355 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1356 
1357 	switch (imsg.hdr.type) {
1358 	case GOT_IMSG_GITCONFIG_INT_VAL:
1359 		if (datalen != sizeof(*val)) {
1360 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1361 			break;
1362 		}
1363 		memcpy(val, imsg.data, sizeof(*val));
1364 		break;
1365 	default:
1366 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1367 		break;
1368 	}
1369 
1370 	imsg_free(&imsg);
1371 	return err;
1372 }
1373 
1374 const struct got_error *
1375 got_privsep_unveil_exec_helpers(void)
1376 {
1377 	const char *helpers[] = {
1378 	    GOT_PATH_PROG_READ_PACK,
1379 	    GOT_PATH_PROG_READ_OBJECT,
1380 	    GOT_PATH_PROG_READ_COMMIT,
1381 	    GOT_PATH_PROG_READ_TREE,
1382 	    GOT_PATH_PROG_READ_BLOB,
1383 	    GOT_PATH_PROG_READ_TAG,
1384 	    GOT_PATH_PROG_READ_GITCONFIG,
1385 	};
1386 	int i;
1387 
1388 	for (i = 0; i < nitems(helpers); i++) {
1389 		if (unveil(helpers[i], "x") == 0)
1390 			continue;
1391 		return got_error_from_errno2("unveil", helpers[i]);
1392 	}
1393 
1394 	return NULL;
1395 }
1396 
1397 void
1398 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
1399 {
1400 	if (close(imsg_fds[0]) != 0) {
1401 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
1402 		_exit(1);
1403 	}
1404 
1405 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
1406 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
1407 		_exit(1);
1408 	}
1409 	if (closefrom(GOT_IMSG_FD_CHILD + 1) == -1) {
1410 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
1411 		_exit(1);
1412 	}
1413 
1414 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
1415 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
1416 		    strerror(errno));
1417 		_exit(1);
1418 	}
1419 }