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Date:: Wed Mar 18 16:13:47 2020 UTC
Message:: apply unveil(2) to 'got clone'
Actions:: History | Blame | Raw File
1 /*
2  * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
3  * Copyright (c) 2020 Ori Bernstein <ori@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include <sys/types.h>
19 #include <sys/queue.h>
20 #include <sys/uio.h>
21 #include <sys/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)
416 {
417 	const struct got_error *err = NULL;
418 	struct ibuf *wbuf;
419 	size_t len, n_have_refs = 0;
420 	struct got_pathlist_entry *pe;
421 
422 	len = sizeof(struct got_imsg_fetch_symrefs);
423 	TAILQ_FOREACH(pe, have_refs, entry) {
424 		struct got_object_id *id = pe->data;
425 		len += sizeof(struct got_imsg_fetch_have_ref) +
426 		    pe->path_len + sizeof(id->sha1);
427 		n_have_refs++;
428 	}
429 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
430 		close(fd);
431 		return got_error(GOT_ERR_NO_SPACE);
432 	}
433 
434 	wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_REQUEST, 0, 0, len);
435 	if (wbuf == NULL) {
436 		close(fd);
437 		return got_error_from_errno("imsg_create FETCH_REQUEST");
438 	}
439 
440 	/* Keep in sync with struct got_imsg_fetch_have_refs definition! */
441 	if (imsg_add(wbuf, &n_have_refs, sizeof(n_have_refs)) == -1) {
442 		err = got_error_from_errno("imsg_add FETCH_REQUEST");
443 		ibuf_free(wbuf);
444 		close(fd);
445 		return err;
446 	}
447 
448 	TAILQ_FOREACH(pe, have_refs, entry) {
449 		const char *name = pe->path;
450 		size_t name_len = pe->path_len;
451 		struct got_object_id *id = pe->data;
452 
453 		/* Keep in sync with struct got_imsg_fetch_have_ref! */
454 		if (imsg_add(wbuf, id->sha1, sizeof(id->sha1)) == -1) {
455 			err = got_error_from_errno("imsg_add FETCH_REQUEST");
456 			ibuf_free(wbuf);
457 			close(fd);
458 			return err;
459 		}
460 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
461 			err = got_error_from_errno("imsg_add FETCH_REQUEST");
462 			ibuf_free(wbuf);
463 			close(fd);
464 			return err;
465 		}
466 		if (imsg_add(wbuf, name, name_len) == -1) {
467 			err = got_error_from_errno("imsg_add FETCH_REQUEST");
468 			ibuf_free(wbuf);
469 			close(fd);
470 			return err;
471 		}
472 	}
473 
474 	wbuf->fd = fd;
475 	imsg_close(ibuf, wbuf);
476 	return flush_imsg(ibuf);
477 }
478 
479 const struct got_error *
480 got_privsep_send_fetch_outfd(struct imsgbuf *ibuf, int fd)
481 {
482 	return send_fd(ibuf, GOT_IMSG_FETCH_OUTFD, fd);
483 }
484 
485 
486 const struct got_error *
487 got_privsep_send_fetch_symrefs(struct imsgbuf *ibuf,
488     struct got_pathlist_head *symrefs)
489 {
490 	const struct got_error *err = NULL;
491 	struct ibuf *wbuf;
492 	size_t len, nsymrefs = 0;
493 	struct got_pathlist_entry *pe;
494 
495 	len = sizeof(struct got_imsg_fetch_symrefs);
496 	TAILQ_FOREACH(pe, symrefs, entry) {
497 		const char *target = pe->data;
498 		len += sizeof(struct got_imsg_fetch_symref) +
499 		    pe->path_len + strlen(target);
500 		nsymrefs++;
501 	}
502 
503 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
504 		return got_error(GOT_ERR_NO_SPACE);
505 
506 	wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_SYMREFS, 0, 0, len);
507 	if (wbuf == NULL)
508 		return got_error_from_errno("imsg_create FETCH_SYMREFS");
509 
510 	/* Keep in sync with struct got_imsg_fetch_symrefs definition! */
511 	if (imsg_add(wbuf, &nsymrefs, sizeof(nsymrefs)) == -1) {
512 		err = got_error_from_errno("imsg_add FETCH_SYMREFS");
513 		ibuf_free(wbuf);
514 		return err;
515 	}
516 
517 	TAILQ_FOREACH(pe, symrefs, entry) {
518 		const char *name = pe->path;
519 		size_t name_len = pe->path_len;
520 		const char *target = pe->data;
521 		size_t target_len = strlen(target);
522 
523 		/* Keep in sync with struct got_imsg_fetch_symref definition! */
524 		if (imsg_add(wbuf, &name_len, sizeof(name_len)) == -1) {
525 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
526 			ibuf_free(wbuf);
527 			return err;
528 		}
529 		if (imsg_add(wbuf, &target_len, sizeof(target_len)) == -1) {
530 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
531 			ibuf_free(wbuf);
532 			return err;
533 		}
534 		if (imsg_add(wbuf, name, name_len) == -1) {
535 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
536 			ibuf_free(wbuf);
537 			return err;
538 		}
539 		if (imsg_add(wbuf, target, target_len) == -1) {
540 			err = got_error_from_errno("imsg_add FETCH_SYMREFS");
541 			ibuf_free(wbuf);
542 			return err;
543 		}
544 	}
545 
546 	wbuf->fd = -1;
547 	imsg_close(ibuf, wbuf);
548 	return flush_imsg(ibuf);
549 }
550 
551 const struct got_error *
552 got_privsep_send_fetch_ref(struct imsgbuf *ibuf,
553     struct got_object_id *refid, const char *refname)
554 {
555 	const struct got_error *err = NULL;
556 	struct ibuf *wbuf;
557 	size_t len, reflen = strlen(refname);
558 
559 	len = sizeof(struct got_imsg_fetch_ref) + reflen;
560 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
561 		return got_error(GOT_ERR_NO_SPACE);
562 
563 	wbuf = imsg_create(ibuf, GOT_IMSG_FETCH_REF, 0, 0, len);
564 	if (wbuf == NULL)
565 		return got_error_from_errno("imsg_create FETCH_REF");
566 
567 	/* Keep in sync with struct got_imsg_fetch_ref definition! */
568 	if (imsg_add(wbuf, refid->sha1, SHA1_DIGEST_LENGTH) == -1) {
569 		err = got_error_from_errno("imsg_add FETCH_REF");
570 		ibuf_free(wbuf);
571 		return err;
572 	}
573 	if (imsg_add(wbuf, refname, reflen) == -1) {
574 		err = got_error_from_errno("imsg_add FETCH_REF");
575 		ibuf_free(wbuf);
576 		return err;
577 	}
578 
579 	wbuf->fd = -1;
580 	imsg_close(ibuf, wbuf);
581 	return flush_imsg(ibuf);
582 }
583 
584 const struct got_error *
585 got_privsep_send_fetch_server_progress(struct imsgbuf *ibuf, const char *msg,
586     size_t msglen)
587 {
588 	if (msglen > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
589 		return got_error(GOT_ERR_NO_SPACE);
590 
591 	if (msglen == 0)
592 		return NULL;
593 
594 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_SERVER_PROGRESS, 0, 0, -1,
595 	    msg, msglen) == -1)
596 		return got_error_from_errno(
597 		    "imsg_compose FETCH_SERVER_PROGRESS");
598 
599 	return flush_imsg(ibuf);
600 }
601 
602 const struct got_error *
603 got_privsep_send_fetch_download_progress(struct imsgbuf *ibuf, off_t bytes)
604 {
605 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_DOWNLOAD_PROGRESS, 0, 0, -1,
606 	    &bytes, sizeof(bytes)) == -1)
607 		return got_error_from_errno(
608 		    "imsg_compose FETCH_DOWNLOAD_PROGRESS");
609 
610 	return flush_imsg(ibuf);
611 }
612 
613 const struct got_error *
614 got_privsep_send_fetch_done(struct imsgbuf *ibuf, struct got_object_id hash)
615 {
616 	if (imsg_compose(ibuf, GOT_IMSG_FETCH_DONE, 0, 0, -1,
617 	    hash.sha1, SHA1_DIGEST_LENGTH) == -1)
618 		return got_error_from_errno("imsg_compose FETCH");
619 	return flush_imsg(ibuf);
620 }
621 
622 
623 const struct got_error *
624 got_privsep_recv_fetch_progress(int *done, struct got_object_id **id,
625     char **refname, struct got_pathlist_head *symrefs, char **server_progress,
626     off_t *packfile_size, struct imsgbuf *ibuf)
627 {
628 	const struct got_error *err = NULL;
629 	struct imsg imsg;
630 	size_t datalen;
631 	struct got_imsg_fetch_symrefs *isymrefs = NULL;
632 	size_t n, remain;
633 	off_t off;
634 	int i;
635 
636 	*done = 0;
637 	*id = NULL;
638 	*refname = NULL;
639 	*server_progress = NULL;
640 
641 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
642 	if (err)
643 		return err;
644 
645 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
646 	switch (imsg.hdr.type) {
647 	case GOT_IMSG_ERROR:
648 		if (datalen < sizeof(struct got_imsg_error)) {
649 			err = got_error(GOT_ERR_PRIVSEP_LEN);
650 			break;
651 		}
652 		err = recv_imsg_error(&imsg, datalen);
653 		break;
654 	case GOT_IMSG_FETCH_SYMREFS:
655 		if (datalen < sizeof(*isymrefs)) {
656 			err = got_error(GOT_ERR_PRIVSEP_LEN);
657 			break;
658 		}
659 		if (isymrefs != NULL) {
660 			err = got_error(GOT_ERR_PRIVSEP_MSG);
661 			break;
662 		}
663 		isymrefs = (struct got_imsg_fetch_symrefs *)imsg.data;
664 		off = sizeof(*isymrefs);
665 		remain = datalen - off;
666 		for (n = 0; n < isymrefs->nsymrefs; n++) {
667 			struct got_imsg_fetch_symref *s;
668 			char *name, *target;
669 			if (remain < sizeof(struct got_imsg_fetch_symref)) {
670 				err = got_error(GOT_ERR_PRIVSEP_LEN);
671 				goto done;
672 			}
673 			s = (struct got_imsg_fetch_symref *)(imsg.data + off);
674 			off += sizeof(*s);
675 			remain -= sizeof(*s);
676 			if (remain < s->name_len) {
677 				err = got_error(GOT_ERR_PRIVSEP_LEN);
678 				goto done;
679 			}
680 			name = strndup(imsg.data + off, s->name_len);
681 			if (name == NULL) {
682 				err = got_error_from_errno("strndup");
683 				goto done;
684 			}
685 			off += s->name_len;
686 			remain -= s->name_len;
687 			if (remain < s->target_len) {
688 				err = got_error(GOT_ERR_PRIVSEP_LEN);
689 				free(name);
690 				goto done;
691 			}
692 			target = strndup(imsg.data + off, s->target_len);
693 			if (target == NULL) {
694 				err = got_error_from_errno("strndup");
695 				free(name);
696 				goto done;
697 			}
698 			off += s->target_len;
699 			remain -= s->target_len;
700 			err = got_pathlist_append(symrefs, name, target);
701 			if (err) {
702 				free(name);
703 				free(target);
704 				goto done;
705 			}
706 		}
707 		break;
708 	case GOT_IMSG_FETCH_REF:
709 		if (datalen <= SHA1_DIGEST_LENGTH) {
710 			err = got_error(GOT_ERR_PRIVSEP_MSG);
711 			break;
712 		}
713 		*id = malloc(sizeof(**id));
714 		if (*id == NULL) {
715 			err = got_error_from_errno("malloc");
716 			break;
717 		}
718 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
719 		*refname = strndup(imsg.data + SHA1_DIGEST_LENGTH,
720 		    datalen - SHA1_DIGEST_LENGTH);
721 		if (*refname == NULL) {
722 			err = got_error_from_errno("strndup");
723 			break;
724 		}
725 		break;
726 	case GOT_IMSG_FETCH_SERVER_PROGRESS:
727 		if (datalen == 0) {
728 			err = got_error(GOT_ERR_PRIVSEP_LEN);
729 			break;
730 		}
731 		*server_progress = strndup(imsg.data, datalen);
732 		if (*server_progress == NULL) {
733 			err = got_error_from_errno("strndup");
734 			break;
735 		}
736 		for (i = 0; i < datalen; i++) {
737 			if (!isprint((unsigned char)(*server_progress)[i]) &&
738 			    !isspace((unsigned char)(*server_progress)[i])) {
739 				err = got_error(GOT_ERR_PRIVSEP_MSG);
740 				free(*server_progress);
741 				*server_progress = NULL;
742 				goto done;
743 			}
744 		}
745 		break;
746 	case GOT_IMSG_FETCH_DOWNLOAD_PROGRESS:
747 		if (datalen < sizeof(*packfile_size)) {
748 			err = got_error(GOT_ERR_PRIVSEP_MSG);
749 			break;
750 		}
751 		memcpy(packfile_size, imsg.data, sizeof(*packfile_size));
752 		break;
753 	case GOT_IMSG_FETCH_DONE:
754 		*id = malloc(sizeof(**id));
755 		if (*id == NULL) {
756 			err = got_error_from_errno("malloc");
757 			break;
758 		}
759 		if (datalen != SHA1_DIGEST_LENGTH) {
760 			err = got_error(GOT_ERR_PRIVSEP_MSG);
761 			break;
762 		}
763 		memcpy((*id)->sha1, imsg.data, SHA1_DIGEST_LENGTH);
764 		*done = 1;
765 		break;
766 	default:
767 		err = got_error(GOT_ERR_PRIVSEP_MSG);
768 		break;
769 	}
770 done:
771 	if (err) {
772 		free(*id);
773 		*id = NULL;
774 		free(*refname);
775 		*refname = NULL;
776 	}
777 	imsg_free(&imsg);
778 	return err;
779 }
780 
781 const struct got_error *
782 got_privsep_send_index_pack_req(struct imsgbuf *ibuf, uint8_t *pack_hash,
783     int fd)
784 {
785 	const struct got_error *err = NULL;
786 
787 	/* Keep in sync with struct got_imsg_index_pack_request */
788 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_REQUEST, 0, 0, fd,
789 	    pack_hash, SHA1_DIGEST_LENGTH) == -1) {
790 		err = got_error_from_errno("imsg_compose INDEX_REQUEST");
791 		close(fd);
792 		return err;
793 	}
794 	return flush_imsg(ibuf);
795 }
796 
797 const struct got_error *
798 got_privsep_send_index_pack_outfd(struct imsgbuf *ibuf, int fd)
799 {
800 	return send_fd(ibuf, GOT_IMSG_IDXPACK_OUTFD, fd);
801 }
802 
803 const struct got_error *
804 got_privsep_send_index_pack_progress(struct imsgbuf *ibuf, int nobj_total,
805     int nobj_indexed, int nobj_loose, int nobj_resolved)
806 {
807 	struct got_imsg_index_pack_progress iprogress;
808 
809 	iprogress.nobj_total = nobj_total;
810 	iprogress.nobj_indexed = nobj_indexed;
811 	iprogress.nobj_loose = nobj_loose;
812 	iprogress.nobj_resolved = nobj_resolved;
813 
814 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_PROGRESS, 0, 0, -1,
815 	    &iprogress, sizeof(iprogress)) == -1)
816 		return got_error_from_errno("imsg_compose IDXPACK_PROGRESS");
817 
818 	return flush_imsg(ibuf);
819 }
820 
821 const struct got_error *
822 got_privsep_send_index_pack_done(struct imsgbuf *ibuf)
823 {
824 	if (imsg_compose(ibuf, GOT_IMSG_IDXPACK_DONE, 0, 0, -1, NULL, 0) == -1)
825 		return got_error_from_errno("imsg_compose FETCH");
826 	return flush_imsg(ibuf);
827 }
828 
829 const struct got_error *
830 got_privsep_recv_index_progress(int *done, int *nobj_total,
831     int *nobj_indexed, int *nobj_loose, int *nobj_resolved,
832     struct imsgbuf *ibuf)
833 {
834 	const struct got_error *err = NULL;
835 	struct imsg imsg;
836 	struct got_imsg_index_pack_progress *iprogress;
837 	size_t datalen;
838 
839 	*done = 0;
840 	*nobj_total = 0;
841 	*nobj_indexed = 0;
842 	*nobj_resolved = 0;
843 
844 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
845 	if (err)
846 		return err;
847 
848 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
849 	switch (imsg.hdr.type) {
850 	case GOT_IMSG_ERROR:
851 		if (datalen < sizeof(struct got_imsg_error)) {
852 			err = got_error(GOT_ERR_PRIVSEP_LEN);
853 			break;
854 		}
855 		err = recv_imsg_error(&imsg, datalen);
856 		break;
857 	case GOT_IMSG_IDXPACK_PROGRESS:
858 		if (datalen < sizeof(*iprogress)) {
859 			err = got_error(GOT_ERR_PRIVSEP_LEN);
860 			break;
861 		}
862 		iprogress = (struct got_imsg_index_pack_progress *)imsg.data;
863 		*nobj_total = iprogress->nobj_total;
864 		*nobj_indexed = iprogress->nobj_indexed;
865 		*nobj_loose = iprogress->nobj_loose;
866 		*nobj_resolved = iprogress->nobj_resolved;
867 		break;
868 	case GOT_IMSG_IDXPACK_DONE:
869 		if (datalen != 0) {
870 			err = got_error(GOT_ERR_PRIVSEP_LEN);
871 			break;
872 		}
873 		*done = 1;
874 		break;
875 	default:
876 		err = got_error(GOT_ERR_PRIVSEP_MSG);
877 		break;
878 	}
879 
880 	imsg_free(&imsg);
881 	return err;
882 }
883 
884 const struct got_error *
885 got_privsep_get_imsg_obj(struct got_object **obj, struct imsg *imsg,
886     struct imsgbuf *ibuf)
887 {
888 	const struct got_error *err = NULL;
889 	struct got_imsg_object *iobj;
890 	size_t datalen = imsg->hdr.len - IMSG_HEADER_SIZE;
891 
892 	if (datalen != sizeof(*iobj))
893 		return got_error(GOT_ERR_PRIVSEP_LEN);
894 	iobj = imsg->data;
895 
896 	*obj = calloc(1, sizeof(**obj));
897 	if (*obj == NULL)
898 		return got_error_from_errno("calloc");
899 
900 	memcpy((*obj)->id.sha1, iobj->id, SHA1_DIGEST_LENGTH);
901 	(*obj)->type = iobj->type;
902 	(*obj)->flags = iobj->flags;
903 	(*obj)->hdrlen = iobj->hdrlen;
904 	(*obj)->size = iobj->size;
905 	/* path_packfile is handled by caller */
906 	if (iobj->flags & GOT_OBJ_FLAG_PACKED) {
907 		(*obj)->pack_offset = iobj->pack_offset;
908 		(*obj)->pack_idx = iobj->pack_idx;
909 	}
910 
911 	return err;
912 }
913 
914 const struct got_error *
915 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
916 {
917 	const struct got_error *err = NULL;
918 	struct imsg imsg;
919 	const size_t min_datalen =
920 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
921 
922 	*obj = NULL;
923 
924 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
925 	if (err)
926 		return err;
927 
928 	switch (imsg.hdr.type) {
929 	case GOT_IMSG_OBJECT:
930 		err = got_privsep_get_imsg_obj(obj, &imsg, ibuf);
931 		break;
932 	default:
933 		err = got_error(GOT_ERR_PRIVSEP_MSG);
934 		break;
935 	}
936 
937 	imsg_free(&imsg);
938 
939 	return err;
940 }
941 
942 static const struct got_error *
943 send_commit_logmsg(struct imsgbuf *ibuf, struct got_commit_object *commit,
944     size_t logmsg_len)
945 {
946 	const struct got_error *err = NULL;
947 	size_t offset, remain;
948 
949 	offset = 0;
950 	remain = logmsg_len;
951 	while (remain > 0) {
952 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
953 
954 		if (imsg_compose(ibuf, GOT_IMSG_COMMIT_LOGMSG, 0, 0, -1,
955 		    commit->logmsg + offset, n) == -1) {
956 			err = got_error_from_errno("imsg_compose "
957 			    "COMMIT_LOGMSG");
958 			break;
959 		}
960 
961 		err = flush_imsg(ibuf);
962 		if (err)
963 			break;
964 
965 		offset += n;
966 		remain -= n;
967 	}
968 
969 	return err;
970 }
971 
972 const struct got_error *
973 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
974 {
975 	const struct got_error *err = NULL;
976 	struct got_imsg_commit_object *icommit;
977 	uint8_t *buf;
978 	size_t len, total;
979 	struct got_object_qid *qid;
980 	size_t author_len = strlen(commit->author);
981 	size_t committer_len = strlen(commit->committer);
982 	size_t logmsg_len = strlen(commit->logmsg);
983 
984 	total = sizeof(*icommit) + author_len + committer_len +
985 	    commit->nparents * SHA1_DIGEST_LENGTH;
986 
987 	buf = malloc(total);
988 	if (buf == NULL)
989 		return got_error_from_errno("malloc");
990 
991 	icommit = (struct got_imsg_commit_object *)buf;
992 	memcpy(icommit->tree_id, commit->tree_id->sha1,
993 	    sizeof(icommit->tree_id));
994 	icommit->author_len = author_len;
995 	icommit->author_time = commit->author_time;
996 	icommit->author_gmtoff = commit->author_gmtoff;
997 	icommit->committer_len = committer_len;
998 	icommit->committer_time = commit->committer_time;
999 	icommit->committer_gmtoff = commit->committer_gmtoff;
1000 	icommit->logmsg_len = logmsg_len;
1001 	icommit->nparents = commit->nparents;
1002 
1003 	len = sizeof(*icommit);
1004 	memcpy(buf + len, commit->author, author_len);
1005 	len += author_len;
1006 	memcpy(buf + len, commit->committer, committer_len);
1007 	len += committer_len;
1008 	SIMPLEQ_FOREACH(qid, &commit->parent_ids, entry) {
1009 		memcpy(buf + len, qid->id, SHA1_DIGEST_LENGTH);
1010 		len += SHA1_DIGEST_LENGTH;
1011 	}
1012 
1013 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
1014 		err = got_error_from_errno("imsg_compose COMMIT");
1015 		goto done;
1016 	}
1017 
1018 	if (logmsg_len == 0 ||
1019 	    logmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1020 		err = flush_imsg(ibuf);
1021 		if (err)
1022 			goto done;
1023 	}
1024 	err = send_commit_logmsg(ibuf, commit, logmsg_len);
1025 done:
1026 	free(buf);
1027 	return err;
1028 }
1029 
1030 static const struct got_error *
1031 get_commit_from_imsg(struct got_commit_object **commit,
1032     struct imsg *imsg, size_t datalen, struct imsgbuf *ibuf)
1033 {
1034 	const struct got_error *err = NULL;
1035 	struct got_imsg_commit_object *icommit;
1036 	size_t len = 0;
1037 	int i;
1038 
1039 	if (datalen < sizeof(*icommit))
1040 		return got_error(GOT_ERR_PRIVSEP_LEN);
1041 
1042 	icommit = imsg->data;
1043 	if (datalen != sizeof(*icommit) + icommit->author_len +
1044 	    icommit->committer_len +
1045 	    icommit->nparents * SHA1_DIGEST_LENGTH)
1046 		return got_error(GOT_ERR_PRIVSEP_LEN);
1047 
1048 	if (icommit->nparents < 0)
1049 		return got_error(GOT_ERR_PRIVSEP_LEN);
1050 
1051 	len += sizeof(*icommit);
1052 
1053 	*commit = got_object_commit_alloc_partial();
1054 	if (*commit == NULL)
1055 		return got_error_from_errno(
1056 		    "got_object_commit_alloc_partial");
1057 
1058 	memcpy((*commit)->tree_id->sha1, icommit->tree_id,
1059 	    SHA1_DIGEST_LENGTH);
1060 	(*commit)->author_time = icommit->author_time;
1061 	(*commit)->author_gmtoff = icommit->author_gmtoff;
1062 	(*commit)->committer_time = icommit->committer_time;
1063 	(*commit)->committer_gmtoff = icommit->committer_gmtoff;
1064 
1065 	if (icommit->author_len == 0) {
1066 		(*commit)->author = strdup("");
1067 		if ((*commit)->author == NULL) {
1068 			err = got_error_from_errno("strdup");
1069 			goto done;
1070 		}
1071 	} else {
1072 		(*commit)->author = malloc(icommit->author_len + 1);
1073 		if ((*commit)->author == NULL) {
1074 			err = got_error_from_errno("malloc");
1075 			goto done;
1076 		}
1077 		memcpy((*commit)->author, imsg->data + len,
1078 		    icommit->author_len);
1079 		(*commit)->author[icommit->author_len] = '\0';
1080 	}
1081 	len += icommit->author_len;
1082 
1083 	if (icommit->committer_len == 0) {
1084 		(*commit)->committer = strdup("");
1085 		if ((*commit)->committer == NULL) {
1086 			err = got_error_from_errno("strdup");
1087 			goto done;
1088 		}
1089 	} else {
1090 		(*commit)->committer =
1091 		    malloc(icommit->committer_len + 1);
1092 		if ((*commit)->committer == NULL) {
1093 			err = got_error_from_errno("malloc");
1094 			goto done;
1095 		}
1096 		memcpy((*commit)->committer, imsg->data + len,
1097 		    icommit->committer_len);
1098 		(*commit)->committer[icommit->committer_len] = '\0';
1099 	}
1100 	len += icommit->committer_len;
1101 
1102 	if (icommit->logmsg_len == 0) {
1103 		(*commit)->logmsg = strdup("");
1104 		if ((*commit)->logmsg == NULL) {
1105 			err = got_error_from_errno("strdup");
1106 			goto done;
1107 		}
1108 	} else {
1109 		size_t offset = 0, remain = icommit->logmsg_len;
1110 
1111 		(*commit)->logmsg = malloc(icommit->logmsg_len + 1);
1112 		if ((*commit)->logmsg == NULL) {
1113 			err = got_error_from_errno("malloc");
1114 			goto done;
1115 		}
1116 		while (remain > 0) {
1117 			struct imsg imsg_log;
1118 			size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1119 			    remain);
1120 
1121 			err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1122 			if (err)
1123 				goto done;
1124 
1125 			if (imsg_log.hdr.type != GOT_IMSG_COMMIT_LOGMSG) {
1126 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1127 				goto done;
1128 			}
1129 
1130 			memcpy((*commit)->logmsg + offset,
1131 			    imsg_log.data, n);
1132 			imsg_free(&imsg_log);
1133 			offset += n;
1134 			remain -= n;
1135 		}
1136 		(*commit)->logmsg[icommit->logmsg_len] = '\0';
1137 	}
1138 
1139 	for (i = 0; i < icommit->nparents; i++) {
1140 		struct got_object_qid *qid;
1141 
1142 		err = got_object_qid_alloc_partial(&qid);
1143 		if (err)
1144 			break;
1145 		memcpy(qid->id, imsg->data + len +
1146 		    i * SHA1_DIGEST_LENGTH, sizeof(*qid->id));
1147 		SIMPLEQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
1148 		(*commit)->nparents++;
1149 	}
1150 done:
1151 	if (err) {
1152 		got_object_commit_close(*commit);
1153 		*commit = NULL;
1154 	}
1155 	return err;
1156 }
1157 
1158 const struct got_error *
1159 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
1160 {
1161 	const struct got_error *err = NULL;
1162 	struct imsg imsg;
1163 	size_t datalen;
1164 	const size_t min_datalen =
1165 	    MIN(sizeof(struct got_imsg_error),
1166 	    sizeof(struct got_imsg_commit_object));
1167 
1168 	*commit = NULL;
1169 
1170 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1171 	if (err)
1172 		return err;
1173 
1174 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1175 
1176 	switch (imsg.hdr.type) {
1177 	case GOT_IMSG_COMMIT:
1178 		err = get_commit_from_imsg(commit, &imsg, datalen, ibuf);
1179 		break;
1180 	default:
1181 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1182 		break;
1183 	}
1184 
1185 	imsg_free(&imsg);
1186 
1187 	return err;
1188 }
1189 
1190 const struct got_error *
1191 got_privsep_send_tree(struct imsgbuf *ibuf, struct got_pathlist_head *entries,
1192     int nentries)
1193 {
1194 	const struct got_error *err = NULL;
1195 	struct got_imsg_tree_object itree;
1196 	struct got_pathlist_entry *pe;
1197 	size_t totlen;
1198 	int nimsg; /* number of imsg queued in ibuf */
1199 
1200 	itree.nentries = nentries;
1201 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
1202 	    == -1)
1203 		return got_error_from_errno("imsg_compose TREE");
1204 
1205 	totlen = sizeof(itree);
1206 	nimsg = 1;
1207 	TAILQ_FOREACH(pe, entries, entry) {
1208 		const char *name = pe->path;
1209 		struct got_parsed_tree_entry *pte = pe->data;
1210 		struct ibuf *wbuf;
1211 		size_t namelen = strlen(name);
1212 		size_t len = sizeof(struct got_imsg_tree_entry) + namelen;
1213 
1214 		if (len > MAX_IMSGSIZE)
1215 			return got_error(GOT_ERR_NO_SPACE);
1216 
1217 		nimsg++;
1218 		if (totlen + len >= MAX_IMSGSIZE - (IMSG_HEADER_SIZE * nimsg)) {
1219 			err = flush_imsg(ibuf);
1220 			if (err)
1221 				return err;
1222 			nimsg = 0;
1223 		}
1224 
1225 		wbuf = imsg_create(ibuf, GOT_IMSG_TREE_ENTRY, 0, 0, len);
1226 		if (wbuf == NULL)
1227 			return got_error_from_errno("imsg_create TREE_ENTRY");
1228 
1229 		/* Keep in sync with struct got_imsg_tree_object definition! */
1230 		if (imsg_add(wbuf, pte->id, SHA1_DIGEST_LENGTH) == -1) {
1231 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1232 			ibuf_free(wbuf);
1233 			return err;
1234 		}
1235 		if (imsg_add(wbuf, &pte->mode, sizeof(pte->mode)) == -1) {
1236 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1237 			ibuf_free(wbuf);
1238 			return err;
1239 		}
1240 
1241 		if (imsg_add(wbuf, name, namelen) == -1) {
1242 			err = got_error_from_errno("imsg_add TREE_ENTRY");
1243 			ibuf_free(wbuf);
1244 			return err;
1245 		}
1246 
1247 		wbuf->fd = -1;
1248 		imsg_close(ibuf, wbuf);
1249 
1250 		totlen += len;
1251 	}
1252 
1253 	return flush_imsg(ibuf);
1254 }
1255 
1256 const struct got_error *
1257 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
1258 {
1259 	const struct got_error *err = NULL;
1260 	const size_t min_datalen =
1261 	    MIN(sizeof(struct got_imsg_error),
1262 	    sizeof(struct got_imsg_tree_object));
1263 	struct got_imsg_tree_object *itree;
1264 	int nentries = 0;
1265 
1266 	*tree = NULL;
1267 get_more:
1268 	err = read_imsg(ibuf);
1269 	if (err)
1270 		goto done;
1271 
1272 	for (;;) {
1273 		struct imsg imsg;
1274 		size_t n;
1275 		size_t datalen;
1276 		struct got_imsg_tree_entry *ite;
1277 		struct got_tree_entry *te = NULL;
1278 
1279 		n = imsg_get(ibuf, &imsg);
1280 		if (n == 0) {
1281 			if (*tree && (*tree)->nentries != nentries)
1282 				goto get_more;
1283 			break;
1284 		}
1285 
1286 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen)
1287 			return got_error(GOT_ERR_PRIVSEP_LEN);
1288 
1289 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1290 
1291 		switch (imsg.hdr.type) {
1292 		case GOT_IMSG_ERROR:
1293 			err = recv_imsg_error(&imsg, datalen);
1294 			break;
1295 		case GOT_IMSG_TREE:
1296 			/* This message should only appear once. */
1297 			if (*tree != NULL) {
1298 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1299 				break;
1300 			}
1301 			if (datalen != sizeof(*itree)) {
1302 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1303 				break;
1304 			}
1305 			itree = imsg.data;
1306 			*tree = malloc(sizeof(**tree));
1307 			if (*tree == NULL) {
1308 				err = got_error_from_errno("malloc");
1309 				break;
1310 			}
1311 			(*tree)->entries = calloc(itree->nentries,
1312 			    sizeof(struct got_tree_entry));
1313 			if ((*tree)->entries == NULL) {
1314 				err = got_error_from_errno("malloc");
1315 				break;
1316 			}
1317 			(*tree)->nentries = itree->nentries;
1318 			(*tree)->refcnt = 0;
1319 			break;
1320 		case GOT_IMSG_TREE_ENTRY:
1321 			/* This message should be preceeded by GOT_IMSG_TREE. */
1322 			if (*tree == NULL) {
1323 				err = got_error(GOT_ERR_PRIVSEP_MSG);
1324 				break;
1325 			}
1326 			if (datalen < sizeof(*ite) || datalen > MAX_IMSGSIZE) {
1327 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1328 				break;
1329 			}
1330 
1331 			/* Remaining data contains the entry's name. */
1332 			datalen -= sizeof(*ite);
1333 			if (datalen == 0 || datalen > MAX_IMSGSIZE) {
1334 				err = got_error(GOT_ERR_PRIVSEP_LEN);
1335 				break;
1336 			}
1337 			ite = imsg.data;
1338 
1339 			if (datalen + 1 > sizeof(te->name)) {
1340 				err = got_error(GOT_ERR_NO_SPACE);
1341 				break;
1342 			}
1343 			te = &(*tree)->entries[nentries];
1344 			memcpy(te->name, imsg.data + sizeof(*ite), datalen);
1345 			te->name[datalen] = '\0';
1346 
1347 			memcpy(te->id.sha1, ite->id, SHA1_DIGEST_LENGTH);
1348 			te->mode = ite->mode;
1349 			te->idx = nentries;
1350 			nentries++;
1351 			break;
1352 		default:
1353 			err = got_error(GOT_ERR_PRIVSEP_MSG);
1354 			break;
1355 		}
1356 
1357 		imsg_free(&imsg);
1358 	}
1359 done:
1360 	if (*tree && (*tree)->nentries != nentries) {
1361 		if (err == NULL)
1362 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1363 		got_object_tree_close(*tree);
1364 		*tree = NULL;
1365 	}
1366 
1367 	return err;
1368 }
1369 
1370 const struct got_error *
1371 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size, size_t hdrlen,
1372     const uint8_t *data)
1373 {
1374 	struct got_imsg_blob iblob;
1375 
1376 	iblob.size = size;
1377 	iblob.hdrlen = hdrlen;
1378 
1379 	if (data) {
1380 		uint8_t *buf;
1381 
1382 		if (size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX)
1383 			return got_error(GOT_ERR_NO_SPACE);
1384 
1385 		buf = malloc(sizeof(iblob) + size);
1386 		if (buf == NULL)
1387 			return got_error_from_errno("malloc");
1388 
1389 		memcpy(buf, &iblob, sizeof(iblob));
1390 		memcpy(buf + sizeof(iblob), data, size);
1391 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, buf,
1392 		   sizeof(iblob) + size) == -1) {
1393 			free(buf);
1394 			return got_error_from_errno("imsg_compose BLOB");
1395 		}
1396 		free(buf);
1397 	} else {
1398 		/* Data has already been written to file descriptor. */
1399 		if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob,
1400 		    sizeof(iblob)) == -1)
1401 			return got_error_from_errno("imsg_compose BLOB");
1402 	}
1403 
1404 
1405 	return flush_imsg(ibuf);
1406 }
1407 
1408 const struct got_error *
1409 got_privsep_recv_blob(uint8_t **outbuf, size_t *size, size_t *hdrlen,
1410     struct imsgbuf *ibuf)
1411 {
1412 	const struct got_error *err = NULL;
1413 	struct imsg imsg;
1414 	struct got_imsg_blob *iblob;
1415 	size_t datalen;
1416 
1417 	*outbuf = NULL;
1418 
1419 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
1420 	if (err)
1421 		return err;
1422 
1423 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1424 
1425 	switch (imsg.hdr.type) {
1426 	case GOT_IMSG_BLOB:
1427 		if (datalen < sizeof(*iblob)) {
1428 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1429 			break;
1430 		}
1431 		iblob = imsg.data;
1432 		*size = iblob->size;
1433 		*hdrlen = iblob->hdrlen;
1434 
1435 		if (datalen == sizeof(*iblob)) {
1436 			/* Data has been written to file descriptor. */
1437 			break;
1438 		}
1439 
1440 		if (*size > GOT_PRIVSEP_INLINE_BLOB_DATA_MAX) {
1441 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1442 			break;
1443 		}
1444 
1445 		*outbuf = malloc(*size);
1446 		if (*outbuf == NULL) {
1447 			err = got_error_from_errno("malloc");
1448 			break;
1449 		}
1450 		memcpy(*outbuf, imsg.data + sizeof(*iblob), *size);
1451 		break;
1452 	default:
1453 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1454 		break;
1455 	}
1456 
1457 	imsg_free(&imsg);
1458 
1459 	return err;
1460 }
1461 
1462 static const struct got_error *
1463 send_tagmsg(struct imsgbuf *ibuf, struct got_tag_object *tag, size_t tagmsg_len)
1464 {
1465 	const struct got_error *err = NULL;
1466 	size_t offset, remain;
1467 
1468 	offset = 0;
1469 	remain = tagmsg_len;
1470 	while (remain > 0) {
1471 		size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE, remain);
1472 
1473 		if (imsg_compose(ibuf, GOT_IMSG_TAG_TAGMSG, 0, 0, -1,
1474 		    tag->tagmsg + offset, n) == -1) {
1475 			err = got_error_from_errno("imsg_compose TAG_TAGMSG");
1476 			break;
1477 		}
1478 
1479 		err = flush_imsg(ibuf);
1480 		if (err)
1481 			break;
1482 
1483 		offset += n;
1484 		remain -= n;
1485 	}
1486 
1487 	return err;
1488 }
1489 
1490 const struct got_error *
1491 got_privsep_send_tag(struct imsgbuf *ibuf, struct got_tag_object *tag)
1492 {
1493 	const struct got_error *err = NULL;
1494 	struct got_imsg_tag_object *itag;
1495 	uint8_t *buf;
1496 	size_t len, total;
1497 	size_t tag_len = strlen(tag->tag);
1498 	size_t tagger_len = strlen(tag->tagger);
1499 	size_t tagmsg_len = strlen(tag->tagmsg);
1500 
1501 	total = sizeof(*itag) + tag_len + tagger_len + tagmsg_len;
1502 
1503 	buf = malloc(total);
1504 	if (buf == NULL)
1505 		return got_error_from_errno("malloc");
1506 
1507 	itag = (struct got_imsg_tag_object *)buf;
1508 	memcpy(itag->id, tag->id.sha1, sizeof(itag->id));
1509 	itag->obj_type = tag->obj_type;
1510 	itag->tag_len = tag_len;
1511 	itag->tagger_len = tagger_len;
1512 	itag->tagger_time = tag->tagger_time;
1513 	itag->tagger_gmtoff = tag->tagger_gmtoff;
1514 	itag->tagmsg_len = tagmsg_len;
1515 
1516 	len = sizeof(*itag);
1517 	memcpy(buf + len, tag->tag, tag_len);
1518 	len += tag_len;
1519 	memcpy(buf + len, tag->tagger, tagger_len);
1520 	len += tagger_len;
1521 
1522 	if (imsg_compose(ibuf, GOT_IMSG_TAG, 0, 0, -1, buf, len) == -1) {
1523 		err = got_error_from_errno("imsg_compose TAG");
1524 		goto done;
1525 	}
1526 
1527 	if (tagmsg_len == 0 ||
1528 	    tagmsg_len + len > MAX_IMSGSIZE - IMSG_HEADER_SIZE) {
1529 		err = flush_imsg(ibuf);
1530 		if (err)
1531 			goto done;
1532 	}
1533 	err = send_tagmsg(ibuf, tag, tagmsg_len);
1534 done:
1535 	free(buf);
1536 	return err;
1537 }
1538 
1539 const struct got_error *
1540 got_privsep_recv_tag(struct got_tag_object **tag, struct imsgbuf *ibuf)
1541 {
1542 	const struct got_error *err = NULL;
1543 	struct imsg imsg;
1544 	struct got_imsg_tag_object *itag;
1545 	size_t len, datalen;
1546 	const size_t min_datalen =
1547 	    MIN(sizeof(struct got_imsg_error),
1548 	    sizeof(struct got_imsg_tag_object));
1549 
1550 	*tag = NULL;
1551 
1552 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1553 	if (err)
1554 		return err;
1555 
1556 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1557 	len = 0;
1558 
1559 	switch (imsg.hdr.type) {
1560 	case GOT_IMSG_TAG:
1561 		if (datalen < sizeof(*itag)) {
1562 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1563 			break;
1564 		}
1565 		itag = imsg.data;
1566 		if (datalen != sizeof(*itag) + itag->tag_len +
1567 		    itag->tagger_len) {
1568 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1569 			break;
1570 		}
1571 		len += sizeof(*itag);
1572 
1573 		*tag = calloc(1, sizeof(**tag));
1574 		if (*tag == NULL) {
1575 			err = got_error_from_errno("calloc");
1576 			break;
1577 		}
1578 
1579 		memcpy((*tag)->id.sha1, itag->id, SHA1_DIGEST_LENGTH);
1580 
1581 		if (itag->tag_len == 0) {
1582 			(*tag)->tag = strdup("");
1583 			if ((*tag)->tag == NULL) {
1584 				err = got_error_from_errno("strdup");
1585 				break;
1586 			}
1587 		} else {
1588 			(*tag)->tag = malloc(itag->tag_len + 1);
1589 			if ((*tag)->tag == NULL) {
1590 				err = got_error_from_errno("malloc");
1591 				break;
1592 			}
1593 			memcpy((*tag)->tag, imsg.data + len,
1594 			    itag->tag_len);
1595 			(*tag)->tag[itag->tag_len] = '\0';
1596 		}
1597 		len += itag->tag_len;
1598 
1599 		(*tag)->obj_type = itag->obj_type;
1600 		(*tag)->tagger_time = itag->tagger_time;
1601 		(*tag)->tagger_gmtoff = itag->tagger_gmtoff;
1602 
1603 		if (itag->tagger_len == 0) {
1604 			(*tag)->tagger = strdup("");
1605 			if ((*tag)->tagger == NULL) {
1606 				err = got_error_from_errno("strdup");
1607 				break;
1608 			}
1609 		} else {
1610 			(*tag)->tagger = malloc(itag->tagger_len + 1);
1611 			if ((*tag)->tagger == NULL) {
1612 				err = got_error_from_errno("malloc");
1613 				break;
1614 			}
1615 			memcpy((*tag)->tagger, imsg.data + len,
1616 			    itag->tagger_len);
1617 			(*tag)->tagger[itag->tagger_len] = '\0';
1618 		}
1619 		len += itag->tagger_len;
1620 
1621 		if (itag->tagmsg_len == 0) {
1622 			(*tag)->tagmsg = strdup("");
1623 			if ((*tag)->tagmsg == NULL) {
1624 				err = got_error_from_errno("strdup");
1625 				break;
1626 			}
1627 		} else {
1628 			size_t offset = 0, remain = itag->tagmsg_len;
1629 
1630 			(*tag)->tagmsg = malloc(itag->tagmsg_len + 1);
1631 			if ((*tag)->tagmsg == NULL) {
1632 				err = got_error_from_errno("malloc");
1633 				break;
1634 			}
1635 			while (remain > 0) {
1636 				struct imsg imsg_log;
1637 				size_t n = MIN(MAX_IMSGSIZE - IMSG_HEADER_SIZE,
1638 				    remain);
1639 
1640 				err = got_privsep_recv_imsg(&imsg_log, ibuf, n);
1641 				if (err)
1642 					return err;
1643 
1644 				if (imsg_log.hdr.type != GOT_IMSG_TAG_TAGMSG)
1645 					return got_error(GOT_ERR_PRIVSEP_MSG);
1646 
1647 				memcpy((*tag)->tagmsg + offset, imsg_log.data,
1648 				    n);
1649 				imsg_free(&imsg_log);
1650 				offset += n;
1651 				remain -= n;
1652 			}
1653 			(*tag)->tagmsg[itag->tagmsg_len] = '\0';
1654 		}
1655 
1656 		break;
1657 	default:
1658 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1659 		break;
1660 	}
1661 
1662 	imsg_free(&imsg);
1663 
1664 	return err;
1665 }
1666 
1667 const struct got_error *
1668 got_privsep_init_pack_child(struct imsgbuf *ibuf, struct got_pack *pack,
1669     struct got_packidx *packidx)
1670 {
1671 	const struct got_error *err = NULL;
1672 	struct got_imsg_packidx ipackidx;
1673 	struct got_imsg_pack ipack;
1674 	int fd;
1675 
1676 	ipackidx.len = packidx->len;
1677 	fd = dup(packidx->fd);
1678 	if (fd == -1)
1679 		return got_error_from_errno("dup");
1680 
1681 	if (imsg_compose(ibuf, GOT_IMSG_PACKIDX, 0, 0, fd, &ipackidx,
1682 	    sizeof(ipackidx)) == -1) {
1683 		err = got_error_from_errno("imsg_compose PACKIDX");
1684 		close(fd);
1685 		return err;
1686 	}
1687 
1688 	if (strlcpy(ipack.path_packfile, pack->path_packfile,
1689 	    sizeof(ipack.path_packfile)) >= sizeof(ipack.path_packfile))
1690 		return got_error(GOT_ERR_NO_SPACE);
1691 	ipack.filesize = pack->filesize;
1692 
1693 	fd = dup(pack->fd);
1694 	if (fd == -1)
1695 		return got_error_from_errno("dup");
1696 
1697 	if (imsg_compose(ibuf, GOT_IMSG_PACK, 0, 0, fd, &ipack, sizeof(ipack))
1698 	    == -1) {
1699 		err = got_error_from_errno("imsg_compose PACK");
1700 		close(fd);
1701 		return err;
1702 	}
1703 
1704 	return flush_imsg(ibuf);
1705 }
1706 
1707 const struct got_error *
1708 got_privsep_send_packed_obj_req(struct imsgbuf *ibuf, int idx,
1709     struct got_object_id *id)
1710 {
1711 	struct got_imsg_packed_object iobj;
1712 
1713 	iobj.idx = idx;
1714 	memcpy(iobj.id, id->sha1, sizeof(iobj.id));
1715 
1716 	if (imsg_compose(ibuf, GOT_IMSG_PACKED_OBJECT_REQUEST, 0, 0, -1,
1717 	    &iobj, sizeof(iobj)) == -1)
1718 		return got_error_from_errno("imsg_compose "
1719 		    "PACKED_OBJECT_REQUEST");
1720 
1721 	return flush_imsg(ibuf);
1722 }
1723 
1724 const struct got_error *
1725 got_privsep_send_gitconfig_parse_req(struct imsgbuf *ibuf, int fd)
1726 {
1727 	const struct got_error *err = NULL;
1728 
1729 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_PARSE_REQUEST, 0, 0, fd,
1730 	    NULL, 0) == -1) {
1731 		err = got_error_from_errno("imsg_compose "
1732 		    "GITCONFIG_PARSE_REQUEST");
1733 		close(fd);
1734 		return err;
1735 	}
1736 
1737 	return flush_imsg(ibuf);
1738 }
1739 
1740 const struct got_error *
1741 got_privsep_send_gitconfig_repository_format_version_req(struct imsgbuf *ibuf)
1742 {
1743 	if (imsg_compose(ibuf,
1744 	    GOT_IMSG_GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST, 0, 0, -1,
1745 	    NULL, 0) == -1)
1746 		return got_error_from_errno("imsg_compose "
1747 		    "GITCONFIG_REPOSITORY_FORMAT_VERSION_REQUEST");
1748 
1749 	return flush_imsg(ibuf);
1750 }
1751 
1752 const struct got_error *
1753 got_privsep_send_gitconfig_author_name_req(struct imsgbuf *ibuf)
1754 {
1755 	if (imsg_compose(ibuf,
1756 	    GOT_IMSG_GITCONFIG_AUTHOR_NAME_REQUEST, 0, 0, -1, NULL, 0) == -1)
1757 		return got_error_from_errno("imsg_compose "
1758 		    "GITCONFIG_AUTHOR_NAME_REQUEST");
1759 
1760 	return flush_imsg(ibuf);
1761 }
1762 
1763 const struct got_error *
1764 got_privsep_send_gitconfig_author_email_req(struct imsgbuf *ibuf)
1765 {
1766 	if (imsg_compose(ibuf,
1767 	    GOT_IMSG_GITCONFIG_AUTHOR_EMAIL_REQUEST, 0, 0, -1, NULL, 0) == -1)
1768 		return got_error_from_errno("imsg_compose "
1769 		    "GITCONFIG_AUTHOR_EMAIL_REQUEST");
1770 
1771 	return flush_imsg(ibuf);
1772 }
1773 
1774 const struct got_error *
1775 got_privsep_send_gitconfig_remotes_req(struct imsgbuf *ibuf)
1776 {
1777 	if (imsg_compose(ibuf,
1778 	    GOT_IMSG_GITCONFIG_REMOTES_REQUEST, 0, 0, -1, NULL, 0) == -1)
1779 		return got_error_from_errno("imsg_compose "
1780 		    "GITCONFIG_REMOTE_REQUEST");
1781 
1782 	return flush_imsg(ibuf);
1783 }
1784 
1785 const struct got_error *
1786 got_privsep_send_gitconfig_owner_req(struct imsgbuf *ibuf)
1787 {
1788 	if (imsg_compose(ibuf,
1789 	    GOT_IMSG_GITCONFIG_OWNER_REQUEST, 0, 0, -1, NULL, 0) == -1)
1790 		return got_error_from_errno("imsg_compose "
1791 		    "GITCONFIG_OWNER_REQUEST");
1792 
1793 	return flush_imsg(ibuf);
1794 }
1795 
1796 const struct got_error *
1797 got_privsep_send_gitconfig_str(struct imsgbuf *ibuf, const char *value)
1798 {
1799 	size_t len = value ? strlen(value) + 1 : 0;
1800 
1801 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_STR_VAL, 0, 0, -1,
1802 	    value, len) == -1)
1803 		return got_error_from_errno("imsg_compose GITCONFIG_STR_VAL");
1804 
1805 	return flush_imsg(ibuf);
1806 }
1807 
1808 const struct got_error *
1809 got_privsep_recv_gitconfig_str(char **str, struct imsgbuf *ibuf)
1810 {
1811 	const struct got_error *err = NULL;
1812 	struct imsg imsg;
1813 	size_t datalen;
1814 	const size_t min_datalen = 0;
1815 
1816 	*str = NULL;
1817 
1818 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1819 	if (err)
1820 		return err;
1821 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1822 
1823 	switch (imsg.hdr.type) {
1824 	case GOT_IMSG_GITCONFIG_STR_VAL:
1825 		if (datalen == 0)
1826 			break;
1827 		*str = malloc(datalen);
1828 		if (*str == NULL) {
1829 			err = got_error_from_errno("malloc");
1830 			break;
1831 		}
1832 		if (strlcpy(*str, imsg.data, datalen) >= datalen)
1833 			err = got_error(GOT_ERR_NO_SPACE);
1834 		break;
1835 	default:
1836 		err = got_error(GOT_ERR_PRIVSEP_MSG);
1837 		break;
1838 	}
1839 
1840 	imsg_free(&imsg);
1841 	return err;
1842 }
1843 
1844 const struct got_error *
1845 got_privsep_send_gitconfig_int(struct imsgbuf *ibuf, int value)
1846 {
1847 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_INT_VAL, 0, 0, -1,
1848 	    &value, sizeof(value)) == -1)
1849 		return got_error_from_errno("imsg_compose GITCONFIG_INT_VAL");
1850 
1851 	return flush_imsg(ibuf);
1852 }
1853 
1854 const struct got_error *
1855 got_privsep_recv_gitconfig_int(int *val, struct imsgbuf *ibuf)
1856 {
1857 	const struct got_error *err = NULL;
1858 	struct imsg imsg;
1859 	size_t datalen;
1860 	const size_t min_datalen =
1861 	    MIN(sizeof(struct got_imsg_error), sizeof(int));
1862 
1863 	*val = 0;
1864 
1865 	err = got_privsep_recv_imsg(&imsg, ibuf, min_datalen);
1866 	if (err)
1867 		return err;
1868 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1869 
1870 	switch (imsg.hdr.type) {
1871 	case GOT_IMSG_GITCONFIG_INT_VAL:
1872 		if (datalen != sizeof(*val)) {
1873 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1874 			break;
1875 		}
1876 		memcpy(val, imsg.data, sizeof(*val));
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_remotes(struct imsgbuf *ibuf,
1889     struct got_remote_repo *remotes, int nremotes)
1890 {
1891 	const struct got_error *err = NULL;
1892 	struct got_imsg_remotes iremotes;
1893 	int i;
1894 
1895 	iremotes.nremotes = nremotes;
1896 	if (imsg_compose(ibuf, GOT_IMSG_GITCONFIG_REMOTES, 0, 0, -1,
1897 	    &iremotes, sizeof(iremotes)) == -1)
1898 		return got_error_from_errno("imsg_compose GITCONFIG_REMOTES");
1899 
1900 	err = flush_imsg(ibuf);
1901 	imsg_clear(ibuf);
1902 	if (err)
1903 		return err;
1904 
1905 	for (i = 0; i < nremotes; i++) {
1906 		struct got_imsg_remote iremote;
1907 		size_t len = sizeof(iremote);
1908 		struct ibuf *wbuf;
1909 
1910 		iremote.name_len = strlen(remotes[i].name);
1911 		len += iremote.name_len;
1912 		iremote.url_len = strlen(remotes[i].url);
1913 		len += iremote.url_len;
1914 
1915 		wbuf = imsg_create(ibuf, GOT_IMSG_GITCONFIG_REMOTE, 0, 0, len);
1916 		if (wbuf == NULL)
1917 			return got_error_from_errno(
1918 			    "imsg_create GITCONFIG_REMOTE");
1919 
1920 		if (imsg_add(wbuf, &iremote, sizeof(iremote)) == -1) {
1921 			err = got_error_from_errno(
1922 			    "imsg_add GIITCONFIG_REMOTE");
1923 			ibuf_free(wbuf);
1924 			return err;
1925 		}
1926 
1927 		if (imsg_add(wbuf, remotes[i].name, iremote.name_len) == -1) {
1928 			err = got_error_from_errno(
1929 			    "imsg_add GIITCONFIG_REMOTE");
1930 			ibuf_free(wbuf);
1931 			return err;
1932 		}
1933 		if (imsg_add(wbuf, remotes[i].url, iremote.url_len) == -1) {
1934 			err = got_error_from_errno(
1935 			    "imsg_add GIITCONFIG_REMOTE");
1936 			ibuf_free(wbuf);
1937 			return err;
1938 		}
1939 
1940 		wbuf->fd = -1;
1941 		imsg_close(ibuf, wbuf);
1942 		err = flush_imsg(ibuf);
1943 		if (err)
1944 			return err;
1945 	}
1946 
1947 	return NULL;
1948 }
1949 
1950 const struct got_error *
1951 got_privsep_recv_gitconfig_remotes(struct got_remote_repo **remotes,
1952     int *nremotes, struct imsgbuf *ibuf)
1953 {
1954 	const struct got_error *err = NULL;
1955 	struct imsg imsg;
1956 	size_t datalen;
1957 	struct got_imsg_remotes iremotes;
1958 	struct got_imsg_remote iremote;
1959 
1960 	*remotes = NULL;
1961 	*nremotes = 0;
1962 	iremotes.nremotes = 0;
1963 
1964 	err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremotes));
1965 	if (err)
1966 		return err;
1967 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1968 
1969 	switch (imsg.hdr.type) {
1970 	case GOT_IMSG_GITCONFIG_REMOTES:
1971 		if (datalen != sizeof(iremotes)) {
1972 			err = got_error(GOT_ERR_PRIVSEP_LEN);
1973 			break;
1974 		}
1975 		memcpy(&iremotes, imsg.data, sizeof(iremotes));
1976 		if (iremotes.nremotes == 0) {
1977 			imsg_free(&imsg);
1978 			return NULL;
1979 		}
1980 		break;
1981 	default:
1982 		imsg_free(&imsg);
1983 		return got_error(GOT_ERR_PRIVSEP_MSG);
1984 	}
1985 
1986 	imsg_free(&imsg);
1987 
1988 	*remotes = recallocarray(NULL, 0, iremotes.nremotes, sizeof(iremote));
1989 	if (*remotes == NULL)
1990 		return got_error_from_errno("recallocarray");
1991 
1992 	while (*nremotes < iremotes.nremotes) {
1993 		struct got_remote_repo *remote;
1994 	
1995 		err = got_privsep_recv_imsg(&imsg, ibuf, sizeof(iremote));
1996 		if (err)
1997 			break;
1998 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
1999 
2000 		switch (imsg.hdr.type) {
2001 		case GOT_IMSG_GITCONFIG_REMOTE:
2002 			remote = &(*remotes)[*nremotes];
2003 			if (datalen < sizeof(iremote)) {
2004 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2005 				break;
2006 			}
2007 			memcpy(&iremote, imsg.data, sizeof(iremote));
2008 			if (iremote.name_len == 0 || iremote.url_len == 0 ||
2009 			    (sizeof(iremote) + iremote.name_len +
2010 			    iremote.url_len) > datalen) {
2011 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2012 				break;
2013 			}
2014 			remote->name = strndup(imsg.data + sizeof(iremote),
2015 			    iremote.name_len);
2016 			if (remote->name == NULL) {
2017 				err = got_error_from_errno("strndup");
2018 				break;
2019 			}
2020 			remote->url = strndup(imsg.data + sizeof(iremote) +
2021 			    iremote.name_len, iremote.url_len);
2022 			if (remote->url == NULL) {
2023 				err = got_error_from_errno("strndup");
2024 				free(remote->name);
2025 				break;
2026 			}
2027 			(*nremotes)++;
2028 			break;
2029 		default:
2030 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2031 			break;
2032 		}
2033 
2034 		imsg_free(&imsg);
2035 		if (err)
2036 			break;
2037 	}
2038 
2039 	if (err) {
2040 		int i;
2041 		for (i = 0; i < *nremotes; i++) {
2042 			free((*remotes)[i].name);
2043 			free((*remotes)[i].url);
2044 		}
2045 		free(*remotes);
2046 		*remotes = NULL;
2047 		*nremotes = 0;
2048 	}
2049 	return err;
2050 }
2051 
2052 const struct got_error *
2053 got_privsep_send_commit_traversal_request(struct imsgbuf *ibuf,
2054      struct got_object_id *id, int idx, const char *path)
2055 {
2056 	const struct got_error *err = NULL;
2057 	struct ibuf *wbuf;
2058 	size_t path_len = strlen(path) + 1;
2059 
2060 	wbuf = imsg_create(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_REQUEST, 0, 0,
2061 	    sizeof(struct got_imsg_commit_traversal_request) + path_len);
2062 	if (wbuf == NULL)
2063 		return got_error_from_errno(
2064 		    "imsg_create COMMIT_TRAVERSAL_REQUEST");
2065 	if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
2066 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2067 		ibuf_free(wbuf);
2068 		return err;
2069 	}
2070 	if (imsg_add(wbuf, &idx, sizeof(idx)) == -1) {
2071 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2072 		ibuf_free(wbuf);
2073 		return err;
2074 	}
2075 	if (imsg_add(wbuf, path, path_len) == -1) {
2076 		err = got_error_from_errno("imsg_add COMMIT_TRAVERSAL_REQUEST");
2077 		ibuf_free(wbuf);
2078 		return err;
2079 	}
2080 
2081 	wbuf->fd = -1;
2082 	imsg_close(ibuf, wbuf);
2083 
2084 	return flush_imsg(ibuf);
2085 }
2086 
2087 const struct got_error *
2088 got_privsep_send_traversed_commits(struct got_object_id *commit_ids, 
2089     size_t ncommits, struct imsgbuf *ibuf)
2090 {
2091 	const struct got_error *err;
2092 	struct ibuf *wbuf;
2093 	int i;
2094 
2095 	wbuf = imsg_create(ibuf, GOT_IMSG_TRAVERSED_COMMITS, 0, 0,
2096 	    sizeof(struct got_imsg_traversed_commits) +
2097 	    ncommits * SHA1_DIGEST_LENGTH);
2098 	if (wbuf == NULL)
2099 		return got_error_from_errno("imsg_create TRAVERSED_COMMITS");
2100 
2101 	if (imsg_add(wbuf, &ncommits, sizeof(ncommits)) == -1) {
2102 		err = got_error_from_errno("imsg_add TRAVERSED_COMMITS");
2103 		ibuf_free(wbuf);
2104 		return err;
2105 	}
2106 	for (i = 0; i < ncommits; i++) {
2107 		struct got_object_id *id = &commit_ids[i];
2108 		if (imsg_add(wbuf, id->sha1, SHA1_DIGEST_LENGTH) == -1) {
2109 			err = got_error_from_errno(
2110 			    "imsg_add TRAVERSED_COMMITS");
2111 			ibuf_free(wbuf);
2112 			return err;
2113 		}
2114 	}
2115 
2116 	wbuf->fd = -1;
2117 	imsg_close(ibuf, wbuf);
2118 
2119 	return flush_imsg(ibuf);
2120 }
2121 
2122 const struct got_error *
2123 got_privsep_recv_traversed_commits(struct got_commit_object **changed_commit,
2124     struct got_object_id **changed_commit_id,
2125     struct got_object_id_queue *commit_ids, struct imsgbuf *ibuf)
2126 {
2127 	const struct got_error *err = NULL;
2128 	struct imsg imsg;
2129 	struct got_imsg_traversed_commits *icommits;
2130 	size_t datalen;
2131 	int i, done = 0;
2132 
2133 	*changed_commit = NULL;
2134 	*changed_commit_id = NULL;
2135 
2136 	while (!done) {
2137 		err = got_privsep_recv_imsg(&imsg, ibuf, 0);
2138 		if (err)
2139 			return err;
2140 
2141 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
2142 		switch (imsg.hdr.type) {
2143 		case GOT_IMSG_TRAVERSED_COMMITS:
2144 			icommits = imsg.data;
2145 			if (datalen != sizeof(*icommits) +
2146 			    icommits->ncommits * SHA1_DIGEST_LENGTH) {
2147 				err = got_error(GOT_ERR_PRIVSEP_LEN);
2148 				break;
2149 			}
2150 			for (i = 0; i < icommits->ncommits; i++) {
2151 				struct got_object_qid *qid;
2152 				uint8_t *sha1 = (uint8_t *)imsg.data +
2153 				    sizeof(*icommits) + i * SHA1_DIGEST_LENGTH;
2154 				err = got_object_qid_alloc_partial(&qid);
2155 				if (err)
2156 					break;
2157 				memcpy(qid->id->sha1, sha1, SHA1_DIGEST_LENGTH);
2158 				SIMPLEQ_INSERT_TAIL(commit_ids, qid, entry);
2159 
2160 				/* The last commit may contain a change. */
2161 				if (i == icommits->ncommits - 1) {
2162 					*changed_commit_id =
2163 					    got_object_id_dup(qid->id);
2164 					if (*changed_commit_id == NULL) {
2165 						err = got_error_from_errno(
2166 						    "got_object_id_dup");
2167 						break;
2168 					}
2169 				}
2170 			}
2171 			break;
2172 		case GOT_IMSG_COMMIT:
2173 			if (*changed_commit_id == NULL) {
2174 				err = got_error(GOT_ERR_PRIVSEP_MSG);
2175 				break;
2176 			}
2177 			err = get_commit_from_imsg(changed_commit, &imsg,
2178 			    datalen, ibuf);
2179 			break;
2180 		case GOT_IMSG_COMMIT_TRAVERSAL_DONE:
2181 			done = 1;
2182 			break;
2183 		default:
2184 			err = got_error(GOT_ERR_PRIVSEP_MSG);
2185 			break;
2186 		}
2187 
2188 		imsg_free(&imsg);
2189 		if (err)
2190 			break;
2191 	}
2192 
2193 	if (err)
2194 		got_object_id_queue_free(commit_ids);
2195 	return err;
2196 }
2197 
2198 const struct got_error *
2199 got_privsep_send_commit_traversal_done(struct imsgbuf *ibuf)
2200 {
2201 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT_TRAVERSAL_DONE, 0, 0, -1,
2202 	    NULL, 0) == -1)
2203 		return got_error_from_errno("imsg_compose TRAVERSAL_DONE");
2204 
2205 	return flush_imsg(ibuf);
2206 }
2207 
2208 const struct got_error *
2209 got_privsep_unveil_exec_helpers(void)
2210 {
2211 	const char *helpers[] = {
2212 	    GOT_PATH_PROG_READ_PACK,
2213 	    GOT_PATH_PROG_READ_OBJECT,
2214 	    GOT_PATH_PROG_READ_COMMIT,
2215 	    GOT_PATH_PROG_READ_TREE,
2216 	    GOT_PATH_PROG_READ_BLOB,
2217 	    GOT_PATH_PROG_READ_TAG,
2218 	    GOT_PATH_PROG_READ_GITCONFIG,
2219 	    GOT_PATH_PROG_FETCH_PACK,
2220 	    GOT_PATH_PROG_INDEX_PACK,
2221 	};
2222 	int i;
2223 
2224 	for (i = 0; i < nitems(helpers); i++) {
2225 		if (unveil(helpers[i], "x") == 0)
2226 			continue;
2227 		return got_error_from_errno2("unveil", helpers[i]);
2228 	}
2229 
2230 	return NULL;
2231 }
2232 
2233 void
2234 got_privsep_exec_child(int imsg_fds[2], const char *path, const char *repo_path)
2235 {
2236 	if (close(imsg_fds[0]) != 0) {
2237 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2238 		_exit(1);
2239 	}
2240 
2241 	if (dup2(imsg_fds[1], GOT_IMSG_FD_CHILD) == -1) {
2242 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2243 		_exit(1);
2244 	}
2245 	if (closefrom(GOT_IMSG_FD_CHILD + 1) == -1) {
2246 		fprintf(stderr, "%s: %s\n", getprogname(), strerror(errno));
2247 		_exit(1);
2248 	}
2249 
2250 	if (execl(path, path, repo_path, (char *)NULL) == -1) {
2251 		fprintf(stderr, "%s: %s: %s\n", getprogname(), path,
2252 		    strerror(errno));
2253 		_exit(1);
2254 	}
2255 }