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Date:: Thu Feb 23 14:21:01 2023 UTC
Message:: provide functions to parse/serialize different hashes it abstracts over the hash type and ensures that object ids are zero'ed before their sha1 digest is written. Needed by the incoming sha256 support. ok stsp@
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1 /*
2  * Copyright (c) 2019 Ori Bernstein <ori@openbsd.org>
3  * Copyright (c) 2021 Stefan Sperling <stsp@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/time.h>
22 #include <sys/stat.h>
23 
24 #include <stdint.h>
25 #include <errno.h>
26 #include <imsg.h>
27 #include <limits.h>
28 #include <signal.h>
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <string.h>
32 #include <ctype.h>
33 #include <sha1.h>
34 #include <sha2.h>
35 #include <fcntl.h>
36 #include <unistd.h>
37 #include <zlib.h>
38 #include <err.h>
39 
40 #include "got_error.h"
41 #include "got_object.h"
42 #include "got_path.h"
43 #include "got_version.h"
44 #include "got_fetch.h"
45 #include "got_reference.h"
46 
47 #include "got_lib_hash.h"
48 #include "got_lib_delta.h"
49 #include "got_lib_object.h"
50 #include "got_lib_object_parse.h"
51 #include "got_lib_privsep.h"
52 #include "got_lib_pack.h"
53 #include "got_lib_pkt.h"
54 #include "got_lib_gitproto.h"
55 #include "got_lib_ratelimit.h"
56 #include "got_lib_poll.h"
57 
58 #ifndef nitems
59 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
60 #endif
61 
62 struct got_object *indexed;
63 static int chattygot;
64 
65 static const struct got_capability got_capabilities[] = {
66 	{ GOT_CAPA_AGENT, "got/" GOT_VERSION_STR },
67 	{ GOT_CAPA_OFS_DELTA, NULL },
68 #if 0
69 	{ GOT_CAPA_SIDE_BAND_64K, NULL },
70 #endif
71 	{ GOT_CAPA_REPORT_STATUS, NULL },
72 	{ GOT_CAPA_DELETE_REFS, NULL },
73 };
74 
75 static const struct got_error *
76 send_upload_progress(struct imsgbuf *ibuf, off_t bytes,
77     struct got_ratelimit *rl)
78 {
79 	const struct got_error *err = NULL;
80 	int elapsed = 0;
81 
82 	if (rl) {
83 		err = got_ratelimit_check(&elapsed, rl);
84 		if (err || !elapsed)
85 			return err;
86 	}
87 
88 	if (imsg_compose(ibuf, GOT_IMSG_SEND_UPLOAD_PROGRESS, 0, 0, -1,
89 	    &bytes, sizeof(bytes)) == -1)
90 		return got_error_from_errno(
91 		    "imsg_compose SEND_UPLOAD_PROGRESS");
92 
93 	return got_privsep_flush_imsg(ibuf);
94 }
95 
96 static const struct got_error *
97 send_pack_request(struct imsgbuf *ibuf)
98 {
99 	if (imsg_compose(ibuf, GOT_IMSG_SEND_PACK_REQUEST, 0, 0, -1,
100 	    NULL, 0) == -1)
101 		return got_error_from_errno("imsg_compose SEND_PACK_REQUEST");
102 	return got_privsep_flush_imsg(ibuf);
103 }
104 
105 static const struct got_error *
106 send_done(struct imsgbuf *ibuf)
107 {
108 	if (imsg_compose(ibuf, GOT_IMSG_SEND_DONE, 0, 0, -1, NULL, 0) == -1)
109 		return got_error_from_errno("imsg_compose SEND_DONE");
110 	return got_privsep_flush_imsg(ibuf);
111 }
112 
113 static const struct got_error *
114 recv_packfd(int *packfd, struct imsgbuf *ibuf)
115 {
116 	const struct got_error *err;
117 	struct imsg imsg;
118 
119 	*packfd = -1;
120 
121 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
122 	if (err)
123 		return err;
124 
125 	if (imsg.hdr.type == GOT_IMSG_STOP) {
126 		err = got_error(GOT_ERR_CANCELLED);
127 		goto done;
128 	}
129 
130 	if (imsg.hdr.type != GOT_IMSG_SEND_PACKFD) {
131 		err = got_error(GOT_ERR_PRIVSEP_MSG);
132 		goto done;
133 	}
134 
135 	if (imsg.hdr.len - IMSG_HEADER_SIZE != 0) {
136 		err = got_error(GOT_ERR_PRIVSEP_LEN);
137 		goto done;
138 	}
139 
140 	*packfd = imsg.fd;
141 done:
142 	imsg_free(&imsg);
143 	return err;
144 }
145 
146 static const struct got_error *
147 send_pack_file(int sendfd, int packfd, struct imsgbuf *ibuf)
148 {
149 	const struct got_error *err;
150 	unsigned char buf[8192];
151 	ssize_t r;
152 	off_t wtotal = 0;
153 	struct got_ratelimit rl;
154 
155 	if (lseek(packfd, 0L, SEEK_SET) == -1)
156 		return got_error_from_errno("lseek");
157 
158 	got_ratelimit_init(&rl, 0, 500);
159 
160 	for (;;) {
161 		r = read(packfd, buf, sizeof(buf));
162 		if (r == -1)
163 			return got_error_from_errno("read");
164 		if (r == 0)
165 			break;
166 		err = got_poll_write_full(sendfd, buf, r);
167 		if (err)
168 			return NULL;
169 		wtotal += r;
170 		err = send_upload_progress(ibuf, wtotal, &rl);
171 		if (err)
172 			return err;
173 	}
174 
175 	return send_upload_progress(ibuf, wtotal, NULL);
176 }
177 
178 static const struct got_error *
179 send_error(const char *buf, size_t len)
180 {
181 	static char msg[1024];
182 	size_t i;
183 
184 	for (i = 0; i < len && i < sizeof(msg) - 1; i++) {
185 		if (!isprint((unsigned char)buf[i]))
186 			return got_error_msg(GOT_ERR_BAD_PACKET,
187 			    "non-printable error message received from server");
188 		msg[i] = buf[i];
189 	}
190 	msg[i] = '\0';
191 	return got_error_msg(GOT_ERR_SEND_FAILED, msg);
192 }
193 
194 static const struct got_error *
195 send_their_ref(struct imsgbuf *ibuf, struct got_object_id *refid,
196     const char *refname)
197 {
198 	struct ibuf *wbuf;
199 	size_t len, reflen = strlen(refname);
200 
201 	len = sizeof(struct got_imsg_send_remote_ref) + reflen;
202 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
203 		return got_error(GOT_ERR_NO_SPACE);
204 
205 	wbuf = imsg_create(ibuf, GOT_IMSG_SEND_REMOTE_REF, 0, 0, len);
206 	if (wbuf == NULL)
207 		return got_error_from_errno("imsg_create SEND_REMOTE_REF");
208 
209 	/* Keep in sync with struct got_imsg_send_remote_ref definition! */
210 	if (imsg_add(wbuf, refid, sizeof(*refid)) == -1)
211 		return got_error_from_errno("imsg_add SEND_REMOTE_REF");
212 	if (imsg_add(wbuf, &reflen, sizeof(reflen)) == -1)
213 		return got_error_from_errno("imsg_add SEND_REMOTE_REF");
214 	if (imsg_add(wbuf, refname, reflen) == -1)
215 		return got_error_from_errno("imsg_add SEND_REMOTE_REF");
216 
217 	wbuf->fd = -1;
218 	imsg_close(ibuf, wbuf);
219 	return got_privsep_flush_imsg(ibuf);
220 }
221 
222 static const struct got_error *
223 send_ref_status(struct imsgbuf *ibuf, const char *refname, int success,
224     struct got_pathlist_head *refs, struct got_pathlist_head *delete_refs)
225 {
226 	struct ibuf *wbuf;
227 	size_t i, len, reflen, errmsglen = 0;
228 	struct got_pathlist_entry *pe;
229 	int ref_valid = 0;
230 	char *eol, *sp;
231 	const char *errmsg = "";
232 
233 	eol = strchr(refname, '\n');
234 	if (eol == NULL) {
235 		return got_error_msg(GOT_ERR_BAD_PACKET,
236 		    "unexpected message from server");
237 	}
238 	*eol = '\0';
239 
240 	sp = strchr(refname, ' ');
241 	if (sp != NULL) {
242 		*sp++ = '\0';
243 		errmsg = sp;
244 		errmsglen = strlen(errmsg);
245 
246 		for (i = 0; i < errmsglen; ++i) {
247 			if (!isprint((unsigned char)errmsg[i])) {
248 				return got_error_msg(GOT_ERR_BAD_PACKET,
249 				    "non-printable error message received "
250 				    "from the server");
251 			}
252 		}
253 	}
254 
255 	reflen = strlen(refname);
256 	if (!got_ref_name_is_valid(refname)) {
257 		return got_error_msg(GOT_ERR_BAD_PACKET,
258 		    "unexpected message from server");
259 	}
260 
261 	TAILQ_FOREACH(pe, refs, entry) {
262 		if (strcmp(refname, pe->path) == 0) {
263 			ref_valid = 1;
264 			break;
265 		}
266 	}
267 	if (!ref_valid) {
268 		TAILQ_FOREACH(pe, delete_refs, entry) {
269 			if (strcmp(refname, pe->path) == 0) {
270 				ref_valid = 1;
271 				break;
272 			}
273 		}
274 	}
275 	if (!ref_valid) {
276 		return got_error_msg(GOT_ERR_BAD_PACKET,
277 		    "unexpected message from server");
278 	}
279 
280 	len = sizeof(struct got_imsg_send_ref_status) + reflen + errmsglen;
281 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
282 		return got_error(GOT_ERR_NO_SPACE);
283 
284 	wbuf = imsg_create(ibuf, GOT_IMSG_SEND_REF_STATUS,
285 	    0, 0, len);
286 	if (wbuf == NULL)
287 		return got_error_from_errno("imsg_create SEND_REF_STATUS");
288 
289 	/* Keep in sync with struct got_imsg_send_ref_status definition! */
290 	if (imsg_add(wbuf, &success, sizeof(success)) == -1)
291 		return got_error_from_errno("imsg_add SEND_REF_STATUS");
292 	if (imsg_add(wbuf, &reflen, sizeof(reflen)) == -1)
293 		return got_error_from_errno("imsg_add SEND_REF_STATUS");
294 	if (imsg_add(wbuf, &errmsglen, sizeof(errmsglen)) == -1)
295 		return got_error_from_errno("imsg_add SEND_REF_STATUS");
296 	if (imsg_add(wbuf, refname, reflen) == -1)
297 		return got_error_from_errno("imsg_add SEND_REF_STATUS");
298 	if (imsg_add(wbuf, errmsg, errmsglen) == -1)
299 		return got_error_from_errno("imsg_add SEND_REF_STATUS");
300 
301 	wbuf->fd = -1;
302 	imsg_close(ibuf, wbuf);
303 	return got_privsep_flush_imsg(ibuf);
304 }
305 
306 static const struct got_error *
307 describe_refchange(int *n, int *sent_my_capabilites,
308     const char *my_capabilities, char *buf, size_t bufsize,
309     const char *refname, const char *old_hashstr, const char *new_hashstr)
310 {
311 	*n = snprintf(buf, bufsize, "%s %s %s",
312 	    old_hashstr, new_hashstr, refname);
313 	if (*n < 0 || (size_t)*n >= bufsize)
314 		return got_error(GOT_ERR_NO_SPACE);
315 
316 	/*
317 	 * We must announce our capabilities along with the first
318 	 * reference. Unfortunately, the protocol requires an embedded
319 	 * NUL as a separator between reference name and capabilities,
320 	 * which we have to deal with here.
321 	 * It also requires a linefeed for terminating packet data.
322 	 */
323 	if (!*sent_my_capabilites && my_capabilities != NULL) {
324 		int m;
325 		if (*n >= bufsize - 1)
326 			return got_error(GOT_ERR_NO_SPACE);
327 		m = snprintf(buf + *n + 1, /* offset after '\0' */
328 		    bufsize - (*n + 1), "%s\n", my_capabilities);
329 		if (m < 0 || *n + m >= bufsize)
330 			return got_error(GOT_ERR_NO_SPACE);
331 		*n += m;
332 		*sent_my_capabilites = 1;
333 	} else {
334 		*n = strlcat(buf, "\n", bufsize);
335 		if (*n >= bufsize)
336 			return got_error(GOT_ERR_NO_SPACE);
337 	}
338 
339 	return NULL;
340 }
341 
342 static const struct got_error *
343 send_pack(int fd, struct got_pathlist_head *refs,
344     struct got_pathlist_head *delete_refs, struct imsgbuf *ibuf)
345 {
346 	const struct got_error *err = NULL;
347 	char buf[GOT_PKT_MAX];
348 	const unsigned char zero_id[SHA1_DIGEST_LENGTH] = { 0 };
349 	char old_hashstr[SHA1_DIGEST_STRING_LENGTH];
350 	char new_hashstr[SHA1_DIGEST_STRING_LENGTH];
351 	struct got_pathlist_head their_refs;
352 	int is_firstpkt = 1;
353 	int n, nsent = 0;
354 	int packfd = -1;
355 	char *id_str = NULL, *refname = NULL;
356 	struct got_object_id *id = NULL;
357 	char *server_capabilities = NULL, *my_capabilities = NULL;
358 	struct got_pathlist_entry *pe;
359 	int sent_my_capabilites = 0;
360 
361 	TAILQ_INIT(&their_refs);
362 
363 	if (TAILQ_EMPTY(refs) && TAILQ_EMPTY(delete_refs))
364 		return got_error(GOT_ERR_SEND_EMPTY);
365 
366 	while (1) {
367 		err = got_pkt_readpkt(&n, fd, buf, sizeof(buf), chattygot);
368 		if (err)
369 			goto done;
370 		if (n == 0)
371 			break;
372 		if (n >= 4 && strncmp(buf, "ERR ", 4) == 0) {
373 			err = send_error(&buf[4], n - 4);
374 			goto done;
375 		}
376 		free(id_str);
377 		free(refname);
378 		err = got_gitproto_parse_refline(&id_str, &refname,
379 		    &server_capabilities, buf, n);
380 		if (err)
381 			goto done;
382 		if (is_firstpkt) {
383 			if (server_capabilities == NULL) {
384 				server_capabilities = strdup("");
385 				if (server_capabilities == NULL) {
386 					err = got_error_from_errno("strdup");
387 					goto done;
388 				}
389 			}
390 			if (chattygot && server_capabilities[0] != '\0')
391 				fprintf(stderr, "%s: server capabilities: %s\n",
392 				    getprogname(), server_capabilities);
393 			err = got_gitproto_match_capabilities(&my_capabilities,
394 			    NULL, server_capabilities, got_capabilities,
395 			    nitems(got_capabilities));
396 			if (err)
397 				goto done;
398 			if (chattygot)
399 				fprintf(stderr, "%s: my capabilities:%s\n",
400 				    getprogname(),
401 				    my_capabilities ? my_capabilities : "");
402 			is_firstpkt = 0;
403 		}
404 		if (strstr(refname, "^{}")) {
405 			if (chattygot) {
406 				fprintf(stderr, "%s: ignoring %s\n",
407 				    getprogname(), refname);
408 			}
409 			continue;
410 		}
411 
412 		id = malloc(sizeof(*id));
413 		if (id == NULL) {
414 			err = got_error_from_errno("malloc");
415 			goto done;
416 		}
417 		if (!got_parse_object_id(id, id_str, GOT_HASH_SHA1)) {
418 			err = got_error(GOT_ERR_BAD_OBJ_ID_STR);
419 			goto done;
420 		}
421 		err = send_their_ref(ibuf, id, refname);
422 		if (err)
423 			goto done;
424 
425 		err = got_pathlist_append(&their_refs, refname, id);
426 		if (err)
427 			goto done;
428 
429 		if (chattygot)
430 			fprintf(stderr, "%s: remote has %s %s\n",
431 			    getprogname(), refname, id_str);
432 		free(id_str);
433 		id_str = NULL;
434 		refname = NULL; /* do not free; owned by their_refs */
435 		id = NULL; /* do not free; owned by their_refs */
436 	}
437 
438 	if (!TAILQ_EMPTY(delete_refs)) {
439 		if (my_capabilities == NULL ||
440 		    strstr(my_capabilities, GOT_CAPA_DELETE_REFS) == NULL) {
441 			err = got_error(GOT_ERR_CAPA_DELETE_REFS);
442 			goto done;
443 		}
444 	}
445 
446 	TAILQ_FOREACH(pe, delete_refs, entry) {
447 		const char *refname = pe->path;
448 		struct got_pathlist_entry *their_pe;
449 		struct got_object_id *their_id = NULL;
450 
451 		TAILQ_FOREACH(their_pe, &their_refs, entry) {
452 			const char *their_refname = their_pe->path;
453 			if (got_path_cmp(refname, their_refname,
454 			    strlen(refname), strlen(their_refname)) == 0) {
455 				their_id = their_pe->data;
456 				break;
457 			}
458 		}
459 		if (their_id == NULL) {
460 			err = got_error_fmt(GOT_ERR_NOT_REF,
461 			    "%s does not exist in remote repository",
462 			    refname);
463 			goto done;
464 		}
465 
466 		got_sha1_digest_to_str(their_id->sha1, old_hashstr,
467 		    sizeof(old_hashstr));
468 		got_sha1_digest_to_str(zero_id, new_hashstr,
469 		    sizeof(new_hashstr));
470 		err = describe_refchange(&n, &sent_my_capabilites,
471 		    my_capabilities, buf, sizeof(buf), refname,
472 		    old_hashstr, new_hashstr);
473 		if (err)
474 			goto done;
475 		err = got_pkt_writepkt(fd, buf, n, chattygot);
476 		if (err)
477 			goto done;
478 		if (chattygot) {
479 			fprintf(stderr, "%s: deleting %s %s\n",
480 			    getprogname(), refname, old_hashstr);
481 		}
482 		nsent++;
483 	}
484 
485 	TAILQ_FOREACH(pe, refs, entry) {
486 		const char *refname = pe->path;
487 		struct got_object_id *id = pe->data;
488 		struct got_object_id *their_id = NULL;
489 		struct got_pathlist_entry *their_pe;
490 
491 		TAILQ_FOREACH(their_pe, &their_refs, entry) {
492 			const char *their_refname = their_pe->path;
493 			if (got_path_cmp(refname, their_refname,
494 			    strlen(refname), strlen(their_refname)) == 0) {
495 				their_id = their_pe->data;
496 				break;
497 			}
498 		}
499 		if (their_id) {
500 			if (got_object_id_cmp(id, their_id) == 0) {
501 				if (chattygot) {
502 					fprintf(stderr,
503 					    "%s: no change for %s\n",
504 					    getprogname(), refname);
505 				}
506 				continue;
507 			}
508 			got_sha1_digest_to_str(their_id->sha1, old_hashstr,
509 			    sizeof(old_hashstr));
510 		} else {
511 			got_sha1_digest_to_str(zero_id, old_hashstr,
512 			    sizeof(old_hashstr));
513 		}
514 		got_sha1_digest_to_str(id->sha1, new_hashstr,
515 		    sizeof(new_hashstr));
516 		err = describe_refchange(&n, &sent_my_capabilites,
517 		    my_capabilities, buf, sizeof(buf), refname,
518 		    old_hashstr, new_hashstr);
519 		if (err)
520 			goto done;
521 		err = got_pkt_writepkt(fd, buf, n, chattygot);
522 		if (err)
523 			goto done;
524 		if (chattygot) {
525 			if (their_id) {
526 				fprintf(stderr, "%s: updating %s %s -> %s\n",
527 				    getprogname(), refname, old_hashstr,
528 				    new_hashstr);
529 			} else {
530 				fprintf(stderr, "%s: creating %s %s\n",
531 				    getprogname(), refname, new_hashstr);
532 			}
533 		}
534 		nsent++;
535 	}
536 	err = got_pkt_flushpkt(fd, chattygot);
537 	if (err)
538 		goto done;
539 
540 	err = send_pack_request(ibuf);
541 	if (err)
542 		goto done;
543 
544 	err = recv_packfd(&packfd, ibuf);
545 	if (err)
546 		goto done;
547 
548 	if (packfd != -1) {
549 		err = send_pack_file(fd, packfd, ibuf);
550 		if (err)
551 			goto done;
552 	}
553 
554 	err = got_pkt_readpkt(&n, fd, buf, sizeof(buf), chattygot);
555 	if (err)
556 		goto done;
557 	if (n >= 4 && strncmp(buf, "ERR ", 4) == 0) {
558 		err = send_error(&buf[4], n - 4);
559 		goto done;
560 	} else if (n < 10 || strncmp(buf, "unpack ok\n", 10) != 0) {
561 		err = got_error_msg(GOT_ERR_BAD_PACKET,
562 		    "unexpected message from server");
563 		goto done;
564 	}
565 
566 	while (nsent > 0) {
567 		err = got_pkt_readpkt(&n, fd, buf, sizeof(buf), chattygot);
568 		if (err)
569 			goto done;
570 		if (n < 3) {
571 			err = got_error_msg(GOT_ERR_BAD_PACKET,
572 			    "unexpected message from server");
573 			goto done;
574 		} else if (n >= 4 && strncmp(buf, "ERR ", 4) == 0) {
575 			err = send_error(&buf[4], n - 4);
576 			goto done;
577 		} else if (strncmp(buf, "ok ", 3) == 0) {
578 			err = send_ref_status(ibuf, buf + 3, 1,
579 			    refs, delete_refs);
580 			if (err)
581 				goto done;
582 		} else if (strncmp(buf, "ng ", 3) == 0) {
583 			err = send_ref_status(ibuf, buf + 3, 0,
584 			    refs, delete_refs);
585 			if (err)
586 				goto done;
587 		} else {
588 			err = got_error_msg(GOT_ERR_BAD_PACKET,
589 			    "unexpected message from server");
590 			goto done;
591 		}
592 		nsent--;
593 	}
594 
595 	err = send_done(ibuf);
596 done:
597 	got_pathlist_free(&their_refs, GOT_PATHLIST_FREE_ALL);
598 	free(id_str);
599 	free(id);
600 	free(refname);
601 	free(server_capabilities);
602 	return err;
603 }
604 
605 int
606 main(int argc, char **argv)
607 {
608 	const struct got_error *err = NULL;
609 	int sendfd = -1;
610 	struct imsgbuf ibuf;
611 	struct imsg imsg;
612 	struct got_pathlist_head refs;
613 	struct got_pathlist_head delete_refs;
614 	struct got_imsg_send_request send_req;
615 	struct got_imsg_send_ref href;
616 	size_t datalen, i;
617 #if 0
618 	static int attached;
619 	while (!attached)
620 		sleep (1);
621 #endif
622 
623 	TAILQ_INIT(&refs);
624 	TAILQ_INIT(&delete_refs);
625 
626 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
627 #ifndef PROFILE
628 	/* revoke access to most system calls */
629 	if (pledge("stdio recvfd", NULL) == -1) {
630 		err = got_error_from_errno("pledge");
631 		got_privsep_send_error(&ibuf, err);
632 		return 1;
633 	}
634 #endif
635 	if ((err = got_privsep_recv_imsg(&imsg, &ibuf, 0)) != 0) {
636 		if (err->code == GOT_ERR_PRIVSEP_PIPE)
637 			err = NULL;
638 		goto done;
639 	}
640 	if (imsg.hdr.type == GOT_IMSG_STOP)
641 		goto done;
642 	if (imsg.hdr.type != GOT_IMSG_SEND_REQUEST) {
643 		err = got_error(GOT_ERR_PRIVSEP_MSG);
644 		goto done;
645 	}
646 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
647 	if (datalen < sizeof(send_req)) {
648 		err = got_error(GOT_ERR_PRIVSEP_LEN);
649 		goto done;
650 	}
651 	memcpy(&send_req, imsg.data, sizeof(send_req));
652 	sendfd = imsg.fd;
653 	imsg_free(&imsg);
654 
655 	if (send_req.verbosity > 0)
656 		chattygot += send_req.verbosity;
657 
658 	for (i = 0; i < send_req.nrefs; i++) {
659 		struct got_object_id *id;
660 		char *refname;
661 
662 		if ((err = got_privsep_recv_imsg(&imsg, &ibuf, 0)) != 0) {
663 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
664 				err = NULL;
665 			goto done;
666 		}
667 		if (imsg.hdr.type == GOT_IMSG_STOP)
668 			goto done;
669 		if (imsg.hdr.type != GOT_IMSG_SEND_REF) {
670 			err = got_error(GOT_ERR_PRIVSEP_MSG);
671 			goto done;
672 		}
673 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
674 		if (datalen < sizeof(href)) {
675 			err = got_error(GOT_ERR_PRIVSEP_LEN);
676 			goto done;
677 		}
678 		memcpy(&href, imsg.data, sizeof(href));
679 		if (datalen - sizeof(href) < href.name_len) {
680 			err = got_error(GOT_ERR_PRIVSEP_LEN);
681 			goto done;
682 		}
683 		refname = malloc(href.name_len + 1);
684 		if (refname == NULL) {
685 			err = got_error_from_errno("malloc");
686 			goto done;
687 		}
688 		memcpy(refname, imsg.data + sizeof(href), href.name_len);
689 		refname[href.name_len] = '\0';
690 
691 		/*
692 		 * Prevent sending of references that won't make any
693 		 * sense outside the local repository's context.
694 		 */
695 		if (strncmp(refname, "refs/got/", 9) == 0 ||
696 		    strncmp(refname, "refs/remotes/", 13) == 0) {
697 			err = got_error_fmt(GOT_ERR_SEND_BAD_REF,
698 			    "%s", refname);
699 			goto done;
700 		}
701 
702 		id = malloc(sizeof(*id));
703 		if (id == NULL) {
704 			free(refname);
705 			err = got_error_from_errno("malloc");
706 			goto done;
707 		}
708 		memcpy(id, &href.id, sizeof(*id));
709 		if (href.delete)
710 			err = got_pathlist_append(&delete_refs, refname, id);
711 		else
712 			err = got_pathlist_append(&refs, refname, id);
713 		if (err) {
714 			free(refname);
715 			free(id);
716 			goto done;
717 		}
718 
719 		imsg_free(&imsg);
720 	}
721 
722 	err = send_pack(sendfd, &refs, &delete_refs, &ibuf);
723 done:
724 	got_pathlist_free(&refs, GOT_PATHLIST_FREE_ALL);
725 	got_pathlist_free(&delete_refs, GOT_PATHLIST_FREE_ALL);
726 	if (sendfd != -1 && close(sendfd) == -1 && err == NULL)
727 		err = got_error_from_errno("close");
728 	if (err != NULL && err->code != GOT_ERR_CANCELLED)  {
729 		fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
730 		got_privsep_send_error(&ibuf, err);
731 	}
732 
733 	exit(0);
734 }