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Date:: Mon Jun 11 01:09:27 2018 UTC
Message:: rename got_parent_id to got_object_qid; better generic name
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1 /*
2  * Copyright (c) 2018 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 
21 #include <stdio.h>
22 #include <stdlib.h>
23 #include <string.h>
24 #include <errno.h>
25 #include <stdint.h>
26 #include <poll.h>
27 #include <imsg.h>
28 #include <sha1.h>
29 #include <zlib.h>
30 
31 #include "got_object.h"
32 #include "got_error.h"
33 
34 #include "got_lib_sha1.h"
35 #include "got_lib_delta.h"
36 #include "got_lib_zbuf.h"
37 #include "got_lib_object.h"
38 #include "got_lib_privsep.h"
39 
40 #ifndef MIN
41 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
42 #endif
43 
44 static const struct got_error *
45 poll_fd(int fd, int events, int timeout)
46 {
47 	struct pollfd pfd[1];
48 	int n;
49 
50 	pfd[0].fd = fd;
51 	pfd[0].events = events;
52 
53 	n = poll(pfd, 1, timeout);
54 	if (n == -1)
55 		return got_error_from_errno();
56 	if (n == 0)
57 		return got_error(GOT_ERR_TIMEOUT);
58 	if (pfd[0].revents & (POLLERR | POLLNVAL))
59 		return got_error_from_errno();
60 	if (pfd[0].revents & (events | POLLHUP))
61 		return NULL;
62 
63 	return got_error(GOT_ERR_INTERRUPT);
64 }
65 
66 static const struct got_error *
67 read_imsg(struct imsgbuf *ibuf)
68 {
69 	const struct got_error *err;
70 	size_t n;
71 
72 	err = poll_fd(ibuf->fd, POLLIN, INFTIM);
73 	if (err)
74 		return err;
75 
76 	n = imsg_read(ibuf);
77 	if (n == -1) {
78 		if (errno == EAGAIN) /* Could be a file-descriptor leak. */
79 			return got_error(GOT_ERR_PRIVSEP_NO_FD);
80 		return got_error(GOT_ERR_PRIVSEP_READ);
81 	}
82 	if (n == 0)
83 		return got_error(GOT_ERR_PRIVSEP_PIPE);
84 
85 	return NULL;
86 }
87 
88 static const struct got_error *
89 recv_one_imsg(struct imsg *imsg, struct imsgbuf *ibuf, size_t min_datalen)
90 {
91 	const struct got_error *err;
92 	ssize_t n;
93 
94 	err = read_imsg(ibuf);
95 	if (err)
96 		return err;
97 
98 	n = imsg_get(ibuf, imsg);
99 	if (n == 0)
100 		return got_error(GOT_ERR_PRIVSEP_READ);
101 
102 	if (imsg->hdr.len < IMSG_HEADER_SIZE + min_datalen)
103 		return got_error(GOT_ERR_PRIVSEP_LEN);
104 
105 	return NULL;
106 }
107 
108 static const struct got_error *
109 recv_imsg_error(struct imsg *imsg, size_t datalen)
110 {
111 	struct got_imsg_error ierr;
112 
113 	if (datalen != sizeof(ierr))
114 		return got_error(GOT_ERR_PRIVSEP_LEN);
115 
116 	memcpy(&ierr, imsg->data, sizeof(ierr));
117 	if (ierr.code == GOT_ERR_ERRNO) {
118 		static struct got_error serr;
119 		serr.code = GOT_ERR_ERRNO;
120 		serr.msg = strerror(ierr.errno_code);
121 		return &serr;
122 	}
123 
124 	return got_error(ierr.code);
125 }
126 
127 /* Attempt to send an error in an imsg. Complain on stderr as a last resort. */
128 void
129 got_privsep_send_error(struct imsgbuf *ibuf, const struct got_error *err)
130 {
131 	const struct got_error *poll_err;
132 	struct got_imsg_error ierr;
133 	int ret;
134 
135 	ierr.code = err->code;
136 	if (err->code == GOT_ERR_ERRNO)
137 		ierr.errno_code = errno;
138 	else
139 		ierr.errno_code = 0;
140 	ret = imsg_compose(ibuf, GOT_IMSG_ERROR, 0, 0, -1, &ierr, sizeof(ierr));
141 	if (ret != -1) {
142 		fprintf(stderr, "%s: error %d \"%s\": imsg_compose: %s\n",
143 		    getprogname(), err->code, err->msg, strerror(errno));
144 		return;
145 	}
146 
147 	poll_err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
148 	if (poll_err) {
149 		fprintf(stderr, "%s: error %d \"%s\": poll: %s\n",
150 		    getprogname(), err->code, err->msg, poll_err->msg);
151 		return;
152 	}
153 
154 	ret = imsg_flush(ibuf);
155 	if (ret == -1) {
156 		fprintf(stderr, "%s: error %d \"%s\": imsg_flush: %s\n",
157 		    getprogname(), err->code, err->msg, strerror(errno));
158 		return;
159 	}
160 }
161 
162 static const struct got_error *
163 flush_imsg(struct imsgbuf *ibuf)
164 {
165 	const struct got_error *err;
166 
167 	err = poll_fd(ibuf->fd, POLLOUT, INFTIM);
168 	if (err)
169 		return err;
170 
171 	if (imsg_flush(ibuf) == -1)
172 		return got_error_from_errno();
173 
174 	return NULL;
175 }
176 
177 const struct got_error *
178 got_privsep_send_obj(struct imsgbuf *ibuf, struct got_object *obj, int ndeltas)
179 {
180 	struct got_imsg_object iobj;
181 
182 	iobj.type = obj->type;
183 	iobj.flags = obj->flags;
184 	iobj.hdrlen = obj->hdrlen;
185 	iobj.size = obj->size;
186 	iobj.ndeltas = ndeltas;
187 
188 	if (ndeltas > 0) {
189 		/* TODO: Handle deltas */
190 	}
191 
192 	if (imsg_compose(ibuf, GOT_IMSG_OBJECT, 0, 0, -1, &iobj, sizeof(iobj))
193 	    == -1)
194 		return got_error_from_errno();
195 
196 	return flush_imsg(ibuf);
197 }
198 
199 const struct got_error *
200 got_privsep_recv_obj(struct got_object **obj, struct imsgbuf *ibuf)
201 {
202 	const struct got_error *err = NULL;
203 	struct imsg imsg;
204 	struct got_imsg_object iobj;
205 	size_t datalen;
206 	int i;
207 	const size_t min_datalen =
208 	    MIN(sizeof(struct got_imsg_error), sizeof(struct got_imsg_object));
209 
210 	*obj = NULL;
211 
212 	err = recv_one_imsg(&imsg, ibuf, min_datalen);
213 	if (err)
214 		return err;
215 
216 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
217 
218 	switch (imsg.hdr.type) {
219 	case GOT_IMSG_ERROR:
220 		err = recv_imsg_error(&imsg, datalen);
221 		break;
222 	case GOT_IMSG_OBJECT:
223 		if (datalen != sizeof(iobj)) {
224 			err = got_error(GOT_ERR_PRIVSEP_LEN);
225 			break;
226 		}
227 
228 		memcpy(&iobj, imsg.data, sizeof(iobj));
229 		if (iobj.ndeltas < 0 ||
230 		    iobj.ndeltas > GOT_DELTA_CHAIN_RECURSION_MAX) {
231 			err = got_error(GOT_ERR_PRIVSEP_LEN);
232 			break;
233 		}
234 
235 		*obj = calloc(1, sizeof(**obj));
236 		if (*obj == NULL) {
237 			err = got_error_from_errno();
238 			break;
239 		}
240 
241 		(*obj)->type = iobj.type;
242 		(*obj)->hdrlen = iobj.hdrlen;
243 		(*obj)->size = iobj.size;
244 		for (i = 0; i < iobj.ndeltas; i++) {
245 			/* TODO: Handle deltas */
246 		}
247 		break;
248 	default:
249 		err = got_error(GOT_ERR_PRIVSEP_MSG);
250 		break;
251 	}
252 
253 	imsg_free(&imsg);
254 
255 	return err;
256 }
257 
258 const struct got_error *
259 got_privsep_send_commit(struct imsgbuf *ibuf, struct got_commit_object *commit)
260 {
261 	const struct got_error *err = NULL;
262 	struct got_imsg_commit_object icommit;
263 	uint8_t *buf;
264 	size_t len, total;
265 	struct got_object_qid *qid;
266 
267 	memcpy(icommit.tree_id, commit->tree_id->sha1, sizeof(icommit.tree_id));
268 	icommit.author_len = strlen(commit->author);
269 	icommit.author_time = commit->author_time;
270 	icommit.author_tzoff_len = strlen(commit->author_tzoff);
271 	icommit.committer_len = strlen(commit->committer);
272 	icommit.committer_time = commit->committer_time;
273 	icommit.committer_tzoff_len = strlen(commit->committer_tzoff);
274 	icommit.logmsg_len = strlen(commit->logmsg);
275 	icommit.nparents = commit->nparents;
276 
277 	total = sizeof(icommit) + icommit.author_len +
278 	    icommit.author_tzoff_len + icommit.committer_len +
279 	    icommit.committer_tzoff_len + icommit.logmsg_len +
280 	    icommit.nparents * SHA1_DIGEST_LENGTH;
281 	/* XXX TODO support very large log messages properly */
282 	if (total > MAX_IMSGSIZE)
283 		return got_error(GOT_ERR_NO_SPACE);
284 
285 	buf = malloc(total);
286 	if (buf == NULL)
287 		return got_error_from_errno();
288 
289 	len = 0;
290 	memcpy(buf + len, &icommit, sizeof(icommit));
291 	len += sizeof(icommit);
292 	memcpy(buf + len, commit->author, icommit.author_len);
293 	len += icommit.author_len;
294 	memcpy(buf + len, commit->author_tzoff, icommit.author_tzoff_len);
295 	len += icommit.author_tzoff_len;
296 	memcpy(buf + len, commit->committer, icommit.committer_len);
297 	len += icommit.committer_len;
298 	memcpy(buf + len, commit->committer_tzoff, icommit.committer_tzoff_len);
299 	len += icommit.committer_tzoff_len;
300 	memcpy(buf + len, commit->logmsg, icommit.logmsg_len);
301 	len += icommit.logmsg_len;
302 	SIMPLEQ_FOREACH(qid, &commit->parent_ids, entry) {
303 		memcpy(buf + len, qid->id, SHA1_DIGEST_LENGTH);
304 		len += SHA1_DIGEST_LENGTH;
305 	}
306 
307 	if (imsg_compose(ibuf, GOT_IMSG_COMMIT, 0, 0, -1, buf, len) == -1) {
308 		err = got_error_from_errno();
309 		goto done;
310 	}
311 
312 	err = flush_imsg(ibuf);
313 done:
314 	free(buf);
315 	return err;
316 }
317 const struct got_error *
318 got_privsep_recv_commit(struct got_commit_object **commit, struct imsgbuf *ibuf)
319 {
320 	const struct got_error *err = NULL;
321 	struct imsg imsg;
322 	struct got_imsg_commit_object icommit;
323 	size_t len, datalen;
324 	int i;
325 	const size_t min_datalen =
326 	    MIN(sizeof(struct got_imsg_error),
327 	    sizeof(struct got_imsg_commit_object));
328 	uint8_t *data;
329 
330 	*commit = NULL;
331 
332 	err = recv_one_imsg(&imsg, ibuf, min_datalen);
333 	if (err)
334 		return err;
335 
336 	data = imsg.data;
337 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
338 	len = 0;
339 
340 	switch (imsg.hdr.type) {
341 	case GOT_IMSG_ERROR:
342 		err = recv_imsg_error(&imsg, datalen);
343 		break;
344 	case GOT_IMSG_COMMIT:
345 		if (datalen < sizeof(icommit)) {
346 			err = got_error(GOT_ERR_PRIVSEP_LEN);
347 			break;
348 		}
349 
350 		memcpy(&icommit, data, sizeof(icommit));
351 		if (datalen != sizeof(icommit) + icommit.author_len +
352 		    icommit.author_tzoff_len + icommit.committer_len +
353 		    icommit.committer_tzoff_len + icommit.logmsg_len +
354 		    icommit.nparents * SHA1_DIGEST_LENGTH) {
355 			err = got_error(GOT_ERR_PRIVSEP_LEN);
356 			break;
357 		}
358 		if (icommit.nparents < 0) {
359 			err = got_error(GOT_ERR_PRIVSEP_LEN);
360 			break;
361 		}
362 		len += sizeof(icommit);
363 
364 		*commit = got_object_commit_alloc_partial();
365 		if (*commit == NULL) {
366 			err = got_error_from_errno();
367 			break;
368 		}
369 
370 		memcpy((*commit)->tree_id->sha1, icommit.tree_id,
371 		    SHA1_DIGEST_LENGTH);
372 
373 		if (icommit.author_len == 0) {
374 			(*commit)->author = strdup("");
375 			if ((*commit)->author == NULL) {
376 				err = got_error_from_errno();
377 				break;
378 			}
379 			(*commit)->author_time = 0;
380 		} else {
381 			(*commit)->author = malloc(icommit.author_len + 1);
382 			if ((*commit)->author == NULL) {
383 				err = got_error_from_errno();
384 				break;
385 			}
386 			memcpy((*commit)->author, data + len,
387 			    icommit.author_len);
388 			(*commit)->author[icommit.author_len] = '\0';
389 		}
390 		len += icommit.author_len;
391 
392 		(*commit)->author_time = icommit.author_time;
393 		if (icommit.author_tzoff_len == 0) {
394 			(*commit)->author_tzoff = strdup("");
395 			if ((*commit)->author_tzoff == NULL) {
396 				err = got_error_from_errno();
397 				break;
398 			}
399 		} else {
400 			(*commit)->author_tzoff =
401 			    malloc(icommit.author_tzoff_len + 1);
402 			if ((*commit)->author_tzoff == NULL) {
403 				err = got_error_from_errno();
404 				break;
405 			}
406 			memcpy((*commit)->author_tzoff, data + len,
407 			    icommit.author_tzoff_len);
408 			(*commit)->author_tzoff[icommit.author_tzoff_len] =
409 			    '\0';
410 		}
411 		len += icommit.author_tzoff_len;
412 
413 		if (icommit.committer_len == 0) {
414 			(*commit)->committer = strdup("");
415 			if ((*commit)->committer == NULL) {
416 				err = got_error_from_errno();
417 				break;
418 			}
419 			(*commit)->committer_time = 0;
420 		} else {
421 			(*commit)->committer =
422 			    malloc(icommit.committer_len + 1);
423 			if ((*commit)->committer == NULL) {
424 				err = got_error_from_errno();
425 				break;
426 			}
427 			memcpy((*commit)->committer, data + len,
428 			    icommit.committer_len);
429 			(*commit)->committer[icommit.committer_len] = '\0';
430 		}
431 		len += icommit.committer_len;
432 
433 		(*commit)->committer_time = icommit.committer_time;
434 		if (icommit.committer_tzoff_len == 0) {
435 			(*commit)->committer_tzoff = strdup("");
436 			if ((*commit)->committer_tzoff == NULL) {
437 				err = got_error_from_errno();
438 				break;
439 			}
440 		} else {
441 			(*commit)->committer_tzoff =
442 			    malloc(icommit.committer_tzoff_len + 1);
443 			if ((*commit)->committer_tzoff == NULL) {
444 				err = got_error_from_errno();
445 				break;
446 			}
447 			memcpy((*commit)->committer_tzoff, data + len,
448 			    icommit.committer_tzoff_len);
449 			(*commit)->committer_tzoff[icommit.committer_tzoff_len]
450 			    = '\0';
451 		}
452 		len += icommit.committer_tzoff_len;
453 
454 		if (icommit.logmsg_len == 0) {
455 			(*commit)->logmsg = strdup("");
456 			if ((*commit)->logmsg == NULL) {
457 				err = got_error_from_errno();
458 				break;
459 			}
460 		} else {
461 			(*commit)->logmsg = malloc(icommit.logmsg_len + 1);
462 			if ((*commit)->logmsg == NULL) {
463 				err = got_error_from_errno();
464 				break;
465 			}
466 			memcpy((*commit)->logmsg, data + len,
467 			    icommit.logmsg_len);
468 			(*commit)->logmsg[icommit.logmsg_len] = '\0';
469 		}
470 		len += icommit.logmsg_len;
471 
472 		for (i = 0; i < icommit.nparents; i++) {
473 			struct got_object_qid *qid;
474 
475 			qid = calloc(1, sizeof(*qid));
476 			if (qid == NULL) {
477 				err = got_error_from_errno();
478 				break;
479 			}
480 			qid->id = calloc(1, sizeof(*qid->id));
481 			if (qid->id == NULL) {
482 				err = got_error_from_errno();
483 				free(qid);
484 				break;
485 			}
486 
487 			memcpy(qid->id, data + len + i * SHA1_DIGEST_LENGTH,
488 			    sizeof(*qid->id));
489 			SIMPLEQ_INSERT_TAIL(&(*commit)->parent_ids, qid, entry);
490 			(*commit)->nparents++;
491 		}
492 		break;
493 	default:
494 		err = got_error(GOT_ERR_PRIVSEP_MSG);
495 		break;
496 	}
497 
498 	imsg_free(&imsg);
499 
500 	return err;
501 }
502 
503 const struct got_error *
504 got_privsep_send_tree(struct imsgbuf *ibuf, struct got_tree_object *tree)
505 {
506 	const struct got_error *err = NULL;
507 	struct got_imsg_tree_object itree;
508 	struct got_tree_entry *te;
509 
510 	itree.nentries = tree->nentries;
511 	if (imsg_compose(ibuf, GOT_IMSG_TREE, 0, 0, -1, &itree, sizeof(itree))
512 	    == -1)
513 		return got_error_from_errno();
514 
515 	err = flush_imsg(ibuf);
516 	if (err)
517 		return err;
518 
519 	SIMPLEQ_FOREACH(te, &tree->entries, entry) {
520 		struct got_imsg_tree_entry ite;
521 		uint8_t *buf = NULL;
522 		size_t len = sizeof(ite) + strlen(te->name);
523 
524 		if (len > MAX_IMSGSIZE)
525 			return got_error(GOT_ERR_NO_SPACE);
526 
527 		buf = malloc(len);
528 		if (buf == NULL)
529 			return got_error_from_errno();
530 
531 		memcpy(ite.id, te->id->sha1, sizeof(ite.id));
532 		ite.mode = te->mode;
533 		memcpy(buf, &ite, sizeof(ite));
534 		memcpy(buf + sizeof(ite), te->name, strlen(te->name));
535 
536 		if (imsg_compose(ibuf, GOT_IMSG_TREE_ENTRY, 0, 0, -1,
537 		    buf, len) == -1)
538 			err = got_error_from_errno();
539 		free(buf);
540 		if (err)
541 			return err;
542 
543 		err = flush_imsg(ibuf);
544 		if (err)
545 			return err;
546 	}
547 
548 	return NULL;
549 }
550 
551 const struct got_error *
552 got_privsep_recv_tree(struct got_tree_object **tree, struct imsgbuf *ibuf)
553 {
554 	const struct got_error *err = NULL;
555 	const size_t min_datalen =
556 	    MIN(sizeof(struct got_imsg_error),
557 	    sizeof(struct got_imsg_tree_object));
558 	struct got_imsg_tree_object itree = { 0 };
559 	int nentries = 0;
560 
561 	*tree = NULL;
562 get_more:
563 	err = read_imsg(ibuf);
564 	if (err)
565 		goto done;
566 
567 	while (1) {
568 		struct imsg imsg;
569 		size_t n;
570 		size_t datalen;
571 		struct got_imsg_tree_entry ite;
572 		struct got_tree_entry *te = NULL;
573 
574 		n = imsg_get(ibuf, &imsg);
575 		if (n == 0) {
576 			if (*tree && (*tree)->nentries != nentries)
577 				goto get_more;
578 			break;
579 		}
580 
581 		if (imsg.hdr.len < IMSG_HEADER_SIZE + min_datalen)
582 			return got_error(GOT_ERR_PRIVSEP_LEN);
583 
584 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
585 
586 		switch (imsg.hdr.type) {
587 		case GOT_IMSG_ERROR:
588 			err = recv_imsg_error(&imsg, datalen);
589 			break;
590 		case GOT_IMSG_TREE:
591 			/* This message should only appear once. */
592 			if (*tree != NULL) {
593 				err = got_error(GOT_ERR_PRIVSEP_MSG);
594 				break;
595 			}
596 			if (datalen != sizeof(itree)) {
597 				err = got_error(GOT_ERR_PRIVSEP_LEN);
598 				break;
599 			}
600 			memcpy(&itree, imsg.data, sizeof(itree));
601 			*tree = calloc(1, sizeof(**tree));
602 			if (*tree == NULL) {
603 				err = got_error_from_errno();
604 				break;
605 			}
606 			(*tree)->nentries = itree.nentries;
607 			SIMPLEQ_INIT(&(*tree)->entries);
608 			break;
609 		case GOT_IMSG_TREE_ENTRY:
610 			/* This message should be preceeded by GOT_IMSG_TREE. */
611 			if (*tree == NULL) {
612 				err = got_error(GOT_ERR_PRIVSEP_MSG);
613 				break;
614 			}
615 			if (datalen < sizeof(ite) || datalen > MAX_IMSGSIZE) {
616 				err = got_error(GOT_ERR_PRIVSEP_LEN);
617 				break;
618 			}
619 
620 			/* Remaining data contains the entry's name. */
621 			datalen -= sizeof(ite);
622 			memcpy(&ite, imsg.data, sizeof(ite));
623 			if (datalen == 0 || datalen > MAX_IMSGSIZE) {
624 				err = got_error(GOT_ERR_PRIVSEP_LEN);
625 				break;
626 			}
627 
628 			te = got_alloc_tree_entry_partial();
629 			if (te == NULL) {
630 				err = got_error_from_errno();
631 				break;
632 			}
633 			te->name = malloc(datalen + 1);
634 			if (te->name == NULL) {
635 				free(te);
636 				err = got_error_from_errno();
637 				break;
638 			}
639 			memcpy(te->name, imsg.data + sizeof(ite), datalen);
640 			te->name[datalen] = '\0';
641 
642 			memcpy(te->id->sha1, ite.id, SHA1_DIGEST_LENGTH);
643 			te->mode = ite.mode;
644 			SIMPLEQ_INSERT_TAIL(&(*tree)->entries, te, entry);
645 			nentries++;
646 			break;
647 		default:
648 			err = got_error(GOT_ERR_PRIVSEP_MSG);
649 			break;
650 		}
651 
652 		imsg_free(&imsg);
653 	}
654 done:
655 	if (*tree && (*tree)->nentries != nentries) {
656 		if (err == NULL)
657 			err = got_error(GOT_ERR_PRIVSEP_LEN);
658 		got_object_tree_close(*tree);
659 		*tree = NULL;
660 	}
661 
662 	return err;
663 }
664 
665 const struct got_error *
666 got_privsep_send_blob(struct imsgbuf *ibuf, size_t size)
667 {
668 	struct got_imsg_blob iblob;
669 
670 	iblob.size = size;
671 	/* Data has already been written to file descriptor. */
672 
673 	if (imsg_compose(ibuf, GOT_IMSG_BLOB, 0, 0, -1, &iblob, sizeof(iblob))
674 	    == -1)
675 		return got_error_from_errno();
676 
677 	return flush_imsg(ibuf);
678 }
679 
680 const struct got_error *
681 got_privsep_recv_blob(size_t *size, struct imsgbuf *ibuf)
682 {
683 	const struct got_error *err = NULL;
684 	struct imsg imsg;
685 	struct got_imsg_blob iblob;
686 	size_t datalen;
687 
688 	err = recv_one_imsg(&imsg, ibuf, 0);
689 	if (err)
690 		return err;
691 
692 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
693 
694 	switch (imsg.hdr.type) {
695 	case GOT_IMSG_ERROR:
696 		err = recv_imsg_error(&imsg, datalen);
697 		break;
698 	case GOT_IMSG_BLOB:
699 		if (datalen != sizeof(iblob))
700 			err = got_error(GOT_ERR_PRIVSEP_LEN);
701 		memcpy(&iblob, imsg.data, sizeof(iblob));
702 		*size = iblob.size;
703 		/* Data has been written to file descriptor. */
704 		break;
705 	default:
706 		err = got_error(GOT_ERR_PRIVSEP_MSG);
707 		break;
708 	}
709 
710 	imsg_free(&imsg);
711 
712 	return err;
713 }