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/uio.h>
20 #include <sys/time.h>
21 #include <sys/stat.h>
22 
23 #include <stdint.h>
24 #include <errno.h>
25 #include <limits.h>
26 #include <signal.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <ctype.h>
31 #include <fcntl.h>
32 #include <unistd.h>
33 #include <zlib.h>
34 #include <err.h>
35 
36 #include "got_error.h"
37 #include "got_object.h"
38 #include "got_path.h"
39 #include "got_version.h"
40 #include "got_fetch.h"
41 #include "got_reference.h"
42 
43 #include "got_lib_sha1.h"
44 #include "got_lib_delta.h"
45 #include "got_lib_object.h"
46 #include "got_lib_object_parse.h"
47 #include "got_lib_privsep.h"
48 #include "got_lib_pack.h"
49 #include "got_lib_pkt.h"
50 #include "got_lib_gitproto.h"
51 #include "got_lib_ratelimit.h"
52 
53 #ifndef nitems
54 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
55 #endif
56 
57 struct got_object *indexed;
58 static int chattygot;
59 
60 static const struct got_capability got_capabilities[] = {
61 	{ GOT_CAPA_AGENT, "got/" GOT_VERSION_STR },
62 	{ GOT_CAPA_OFS_DELTA, NULL },
63 #if 0
64 	{ GOT_CAPA_SIDE_BAND_64K, NULL },
65 #endif
66 	{ GOT_CAPA_REPORT_STATUS, NULL },
67 	{ GOT_CAPA_DELETE_REFS, NULL },
68 };
69 
70 static const struct got_error *
71 send_upload_progress(struct imsgbuf *ibuf, off_t bytes,
72     struct got_ratelimit *rl)
73 {
74 	const struct got_error *err = NULL;
75 	int elapsed = 0;
76 
77 	if (rl) {
78 		err = got_ratelimit_check(&elapsed, rl);
79 		if (err || !elapsed)
80 			return err;
81 	}
82 
83 	if (imsg_compose(ibuf, GOT_IMSG_SEND_UPLOAD_PROGRESS, 0, 0, -1,
84 	    &bytes, sizeof(bytes)) == -1)
85 		return got_error_from_errno(
86 		    "imsg_compose SEND_UPLOAD_PROGRESS");
87 
88 	return got_privsep_flush_imsg(ibuf);
89 }
90 
91 static const struct got_error *
92 send_pack_request(struct imsgbuf *ibuf)
93 {
94 	if (imsg_compose(ibuf, GOT_IMSG_SEND_PACK_REQUEST, 0, 0, -1,
95 	    NULL, 0) == -1)
96 		return got_error_from_errno("imsg_compose SEND_PACK_REQUEST");
97 	return got_privsep_flush_imsg(ibuf);
98 }
99 
100 static const struct got_error *
101 send_done(struct imsgbuf *ibuf)
102 {
103 	if (imsg_compose(ibuf, GOT_IMSG_SEND_DONE, 0, 0, -1, NULL, 0) == -1)
104 		return got_error_from_errno("imsg_compose SEND_DONE");
105 	return got_privsep_flush_imsg(ibuf);
106 }
107 
108 static const struct got_error *
109 recv_packfd(int *packfd, struct imsgbuf *ibuf)
110 {
111 	const struct got_error *err;
112 	struct imsg imsg;
113 
114 	*packfd = -1;
115 
116 	err = got_privsep_recv_imsg(&imsg, ibuf, 0);
117 	if (err)
118 		return err;
119 		
120 	if (imsg.hdr.type == GOT_IMSG_STOP) {
121 		err = got_error(GOT_ERR_CANCELLED);
122 		goto done;
123 	}
124 
125 	if (imsg.hdr.type != GOT_IMSG_SEND_PACKFD) {
126 		err = got_error(GOT_ERR_PRIVSEP_MSG);
127 		goto done;
128 	}
129 
130 	if (imsg.hdr.len - IMSG_HEADER_SIZE != 0) {
131 		err = got_error(GOT_ERR_PRIVSEP_LEN);
132 		goto done;
133 	}
134 
135 	*packfd = imsg.fd;
136 done:
137 	imsg_free(&imsg);
138 	return err;
139 }
140 
141 static const struct got_error *
142 send_pack_file(int sendfd, int packfd, struct imsgbuf *ibuf)
143 {
144 	const struct got_error *err;
145 	unsigned char buf[8192];
146 	ssize_t r, w;
147 	off_t wtotal = 0;
148 	struct got_ratelimit rl;
149 
150 	if (lseek(packfd, 0L, SEEK_SET) == -1)
151 		return got_error_from_errno("lseek");
152 
153 	got_ratelimit_init(&rl, 0, 500);
154 
155 	for (;;) {
156 		r = read(packfd, buf, sizeof(buf));
157 		if (r == -1)
158 			return got_error_from_errno("read");
159 		if (r == 0)
160 			break;
161 		w = write(sendfd, buf, r);
162 		if (w == -1)
163 			return got_error_from_errno("write");
164 		if (w != r)
165 			return got_error(GOT_ERR_IO);
166 		wtotal += w;
167 		err = send_upload_progress(ibuf, wtotal, &rl);
168 		if (err)
169 			return err;
170 	}
171 
172 	return send_upload_progress(ibuf, wtotal, NULL);
173 }
174 
175 static const struct got_error *
176 send_error(const char *buf, size_t len)
177 {
178 	static char msg[1024];
179 	size_t i;
180 
181 	for (i = 0; i < len && i < sizeof(msg) - 1; i++) {
182 		if (!isprint(buf[i]))
183 			return got_error_msg(GOT_ERR_BAD_PACKET,
184 			    "non-printable error message received from server");
185 		msg[i] = buf[i];
186 	}
187 	msg[i] = '\0';
188 	return got_error_msg(GOT_ERR_SEND_FAILED, msg);
189 }
190 
191 static const struct got_error *
192 send_their_ref(struct imsgbuf *ibuf, struct got_object_id *refid,
193     const char *refname)
194 {
195 	struct ibuf *wbuf;
196 	size_t len, reflen = strlen(refname);
197 
198 	len = sizeof(struct got_imsg_send_remote_ref) + reflen;
199 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
200 		return got_error(GOT_ERR_NO_SPACE);
201 
202 	wbuf = imsg_create(ibuf, GOT_IMSG_SEND_REMOTE_REF, 0, 0, len);
203 	if (wbuf == NULL)
204 		return got_error_from_errno("imsg_create SEND_REMOTE_REF");
205 
206 	/* Keep in sync with struct got_imsg_send_remote_ref definition! */
207 	if (imsg_add(wbuf, refid->sha1, SHA1_DIGEST_LENGTH) == -1)
208 		return got_error_from_errno("imsg_add SEND_REMOTE_REF");
209 	if (imsg_add(wbuf, &reflen, sizeof(reflen)) == -1)
210 		return got_error_from_errno("imsg_add SEND_REMOTE_REF");
211 	if (imsg_add(wbuf, refname, reflen) == -1)
212 		return got_error_from_errno("imsg_add SEND_REMOTE_REF");
213 
214 	wbuf->fd = -1;
215 	imsg_close(ibuf, wbuf);
216 	return got_privsep_flush_imsg(ibuf);
217 }
218 
219 static const struct got_error *
220 send_ref_status(struct imsgbuf *ibuf, const char *refname, int success,
221     struct got_pathlist_head *refs, struct got_pathlist_head *delete_refs)
222 {
223 	struct ibuf *wbuf;
224 	size_t len, reflen = strlen(refname);
225 	struct got_pathlist_entry *pe;
226 	int ref_valid = 0;
227 	char *eol;
228 
229 	eol = strchr(refname, '\n');
230 	if (eol == NULL) {
231 		return got_error_msg(GOT_ERR_BAD_PACKET,
232 		    "unexpected message from server");
233 	}
234 	*eol = '\0';
235 
236 	TAILQ_FOREACH(pe, refs, entry) {
237 		if (strcmp(refname, pe->path) == 0) {
238 			ref_valid = 1;
239 			break;
240 		}
241 	}
242 	if (!ref_valid) {
243 		TAILQ_FOREACH(pe, delete_refs, entry) {
244 			if (strcmp(refname, pe->path) == 0) {
245 				ref_valid = 1;
246 				break;
247 			}
248 		}
249 	}
250 	if (!ref_valid) {
251 		return got_error_msg(GOT_ERR_BAD_PACKET,
252 		    "unexpected message from server");
253 	}
254 
255 	len = sizeof(struct got_imsg_send_ref_status) + reflen;
256 	if (len >= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
257 		return got_error(GOT_ERR_NO_SPACE);
258 
259 	wbuf = imsg_create(ibuf, GOT_IMSG_SEND_REF_STATUS,
260 	    0, 0, len);
261 	if (wbuf == NULL)
262 		return got_error_from_errno("imsg_create SEND_REF_STATUS");
263 
264 	/* Keep in sync with struct got_imsg_send_ref_status definition! */
265 	if (imsg_add(wbuf, &success, sizeof(success)) == -1)
266 		return got_error_from_errno("imsg_add SEND_REF_STATUS");
267 	if (imsg_add(wbuf, &reflen, sizeof(reflen)) == -1)
268 		return got_error_from_errno("imsg_add SEND_REF_STATUS");
269 	if (imsg_add(wbuf, refname, reflen) == -1)
270 		return got_error_from_errno("imsg_add SEND_REF_STATUS");
271 
272 	wbuf->fd = -1;
273 	imsg_close(ibuf, wbuf);
274 	return got_privsep_flush_imsg(ibuf);
275 }
276 
277 static const struct got_error *
278 describe_refchange(int *n, int *sent_my_capabilites,
279     const char *my_capabilities, char *buf, size_t bufsize,
280     const char *refname, const char *old_hashstr, const char *new_hashstr)
281 {
282 	*n = snprintf(buf, bufsize, "%s %s %s",
283 	    old_hashstr, new_hashstr, refname);
284 	if (*n >= bufsize)
285 		return got_error(GOT_ERR_NO_SPACE);
286 
287 	/*
288 	 * We must announce our capabilities along with the first
289 	 * reference. Unfortunately, the protocol requires an embedded
290 	 * NUL as a separator between reference name and capabilities,
291 	 * which we have to deal with here.
292 	 * It also requires a linefeed for terminating packet data.
293 	 */
294 	if (!*sent_my_capabilites && my_capabilities != NULL) {
295 		int m;
296 		if (*n >= bufsize - 1)
297 			return got_error(GOT_ERR_NO_SPACE);
298 		m = snprintf(buf + *n + 1, /* offset after '\0' */
299 		    bufsize - (*n + 1), "%s\n", my_capabilities);
300 		if (*n + m >= bufsize)
301 			return got_error(GOT_ERR_NO_SPACE);
302 		*n += m;
303 		*sent_my_capabilites = 1;
304 	} else {
305 		*n = strlcat(buf, "\n", bufsize);
306 		if (*n >= bufsize)
307 			return got_error(GOT_ERR_NO_SPACE);
308 	}
309 
310 	return NULL;
311 }
312 
313 static const struct got_error *
314 send_pack(int fd, struct got_pathlist_head *refs,
315     struct got_pathlist_head *delete_refs, struct imsgbuf *ibuf)
316 {
317 	const struct got_error *err = NULL;
318 	char buf[GOT_PKT_MAX];
319 	const unsigned char zero_id[SHA1_DIGEST_LENGTH] = { 0 };
320 	char old_hashstr[SHA1_DIGEST_STRING_LENGTH];
321 	char new_hashstr[SHA1_DIGEST_STRING_LENGTH];
322 	struct got_pathlist_head their_refs;
323 	int is_firstpkt = 1;
324 	int n, nsent = 0;
325 	int packfd = -1;
326 	char *id_str = NULL, *refname = NULL;
327 	struct got_object_id *id = NULL;
328 	char *server_capabilities = NULL, *my_capabilities = NULL;
329 	struct got_pathlist_entry *pe;
330 	int sent_my_capabilites = 0;
331 
332 	TAILQ_INIT(&their_refs);
333 
334 	if (TAILQ_EMPTY(refs) && TAILQ_EMPTY(delete_refs))
335 		return got_error(GOT_ERR_SEND_EMPTY);
336 
337 	while (1) {
338 		err = got_pkt_readpkt(&n, fd, buf, sizeof(buf), chattygot);
339 		if (err)
340 			goto done;
341 		if (n == 0)
342 			break;
343 		if (n >= 4 && strncmp(buf, "ERR ", 4) == 0) {
344 			err = send_error(&buf[4], n - 4);
345 			goto done;
346 		}
347 		free(id_str);
348 		free(refname);
349 		err = got_gitproto_parse_refline(&id_str, &refname,
350 		    &server_capabilities, buf, n);
351 		if (err)
352 			goto done;
353 		if (is_firstpkt) {
354 			if (chattygot && server_capabilities[0] != '\0')
355 				fprintf(stderr, "%s: server capabilities: %s\n",
356 				    getprogname(), server_capabilities);
357 			err = got_gitproto_match_capabilities(&my_capabilities,
358 			    NULL, server_capabilities, got_capabilities,
359 			    nitems(got_capabilities));
360 			if (err)
361 				goto done;
362 			if (chattygot)
363 				fprintf(stderr, "%s: my capabilities:%s\n",
364 				    getprogname(), my_capabilities);
365 			is_firstpkt = 0;
366 		}
367 		if (strstr(refname, "^{}")) {
368 			if (chattygot) {
369 				fprintf(stderr, "%s: ignoring %s\n",
370 				    getprogname(), refname);
371 			}
372 			continue;
373 		}
374 
375 		id = malloc(sizeof(*id));
376 		if (id == NULL) {
377 			err = got_error_from_errno("malloc");
378 			goto done;
379 		}
380 		if (!got_parse_sha1_digest(id->sha1, id_str)) {
381 			err = got_error(GOT_ERR_BAD_OBJ_ID_STR);
382 			goto done;
383 		}
384 		err = send_their_ref(ibuf, id, refname);
385 		if (err)
386 			goto done;
387 
388 		err = got_pathlist_append(&their_refs, refname, id);
389 		if (chattygot)
390 			fprintf(stderr, "%s: remote has %s %s\n",
391 			    getprogname(), refname, id_str);
392 		free(id_str);
393 		id_str = NULL;
394 		refname = NULL; /* do not free; owned by their_refs */
395 		id = NULL; /* do not free; owned by their_refs */
396 	}
397 
398 	if (!TAILQ_EMPTY(delete_refs)) {
399 		if (my_capabilities == NULL ||
400 		    strstr(my_capabilities, GOT_CAPA_DELETE_REFS) == NULL) {
401 			err = got_error(GOT_ERR_CAPA_DELETE_REFS);
402 			goto done;
403 		}
404 	}
405 
406 	TAILQ_FOREACH(pe, delete_refs, entry) {
407 		const char *refname = pe->path;
408 		struct got_pathlist_entry *their_pe;
409 		struct got_object_id *their_id = NULL;
410 
411 		TAILQ_FOREACH(their_pe, &their_refs, entry) {
412 			const char *their_refname = their_pe->path;
413 			if (got_path_cmp(refname, their_refname,
414 			    strlen(refname), strlen(their_refname)) == 0) {
415 				their_id = their_pe->data;
416 				break;
417 			}
418 		}
419 		if (their_id == NULL) {
420 			err = got_error_fmt(GOT_ERR_NOT_REF,
421 			    "%s does not exist in remote repository",
422 			    refname);
423 			goto done;
424 		}
425 
426 		got_sha1_digest_to_str(their_id->sha1, old_hashstr,
427 		    sizeof(old_hashstr));
428 		got_sha1_digest_to_str(zero_id, new_hashstr,
429 		    sizeof(new_hashstr));
430 		err = describe_refchange(&n, &sent_my_capabilites,
431 		    my_capabilities, buf, sizeof(buf), refname,
432 		    old_hashstr, new_hashstr);
433 		if (err)
434 			goto done;
435 		err = got_pkt_writepkt(fd, buf, n, chattygot);
436 		if (err)
437 			goto done;
438 		if (chattygot) {
439 			fprintf(stderr, "%s: deleting %s %s\n",
440 			    getprogname(), refname, old_hashstr);
441 		}
442 		nsent++;
443 	}
444 
445 	TAILQ_FOREACH(pe, refs, entry) {
446 		const char *refname = pe->path;
447 		struct got_object_id *id = pe->data;
448 		struct got_object_id *their_id = NULL;
449 		struct got_pathlist_entry *their_pe;
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) {
460 			if (got_object_id_cmp(id, their_id) == 0) {
461 				if (chattygot) {
462 					fprintf(stderr,
463 					    "%s: no change for %s\n",
464 					    getprogname(), refname);
465 				}
466 				continue;
467 			}
468 			got_sha1_digest_to_str(their_id->sha1, old_hashstr,
469 			    sizeof(old_hashstr));
470 		} else {
471 			got_sha1_digest_to_str(zero_id, old_hashstr,
472 			    sizeof(old_hashstr));
473 		}
474 		got_sha1_digest_to_str(id->sha1, new_hashstr,
475 		    sizeof(new_hashstr));
476 		err = describe_refchange(&n, &sent_my_capabilites,
477 		    my_capabilities, buf, sizeof(buf), refname,
478 		    old_hashstr, new_hashstr);
479 		if (err)
480 			goto done;
481 		err = got_pkt_writepkt(fd, buf, n, chattygot);
482 		if (err)
483 			goto done;
484 		if (chattygot) {
485 			if (their_id) {
486 				fprintf(stderr, "%s: updating %s %s -> %s\n",
487 				    getprogname(), refname, old_hashstr,
488 				    new_hashstr);
489 			} else {
490 				fprintf(stderr, "%s: creating %s %s\n",
491 				    getprogname(), refname, new_hashstr);
492 			}
493 		}
494 		nsent++;
495 	}
496 	err = got_pkt_flushpkt(fd, chattygot);
497 	if (err)
498 		goto done;
499 
500 	err = send_pack_request(ibuf);
501 	if (err)
502 		goto done;
503 
504 	err = recv_packfd(&packfd, ibuf);
505 	if (err)
506 		goto done;
507 
508 	if (packfd != -1) {
509 		err = send_pack_file(fd, packfd, ibuf);
510 		if (err)
511 			goto done;
512 	}
513 
514 	err = got_pkt_readpkt(&n, fd, buf, sizeof(buf), chattygot);
515 	if (err)
516 		goto done;
517 	if (n >= 4 && strncmp(buf, "ERR ", 4) == 0) {
518 		err = send_error(&buf[4], n - 4);
519 		goto done;
520 	} else if (n < 10 || strncmp(buf, "unpack ok\n", 10) != 0) {
521 		err = got_error_msg(GOT_ERR_BAD_PACKET,
522 		    "unexpected message from server");
523 		goto done;
524 	}
525 
526 	while (nsent > 0) {
527 		err = got_pkt_readpkt(&n, fd, buf, sizeof(buf), chattygot);
528 		if (err)
529 			goto done;
530 		if (n < 3) {
531 			err = got_error_msg(GOT_ERR_BAD_PACKET,
532 			    "unexpected message from server");
533 			goto done;
534 		} else if (strncmp(buf, "ok ", 3) == 0) {
535 			err = send_ref_status(ibuf, buf + 3, 1,
536 			    refs, delete_refs);
537 			if (err)
538 				goto done;
539 		} else if (strncmp(buf, "ng ", 3) == 0) {
540 			err = send_ref_status(ibuf, buf + 3, 0,
541 			    refs, delete_refs);
542 			if (err)
543 				goto done;
544 		} else {
545 			err = got_error_msg(GOT_ERR_BAD_PACKET,
546 			    "unexpected message from server");
547 			goto done;
548 		}
549 		nsent--;
550 	}
551 
552 	err = send_done(ibuf);
553 done:
554 	TAILQ_FOREACH(pe, &their_refs, entry) {
555 		free((void *)pe->path);
556 		free(pe->data);
557 	}
558 	got_pathlist_free(&their_refs);
559 	free(id_str);
560 	free(id);
561 	free(refname);
562 	free(server_capabilities);
563 	return err;
564 }
565 
566 int
567 main(int argc, char **argv)
568 {
569 	const struct got_error *err = NULL;
570 	int sendfd;
571 	struct imsgbuf ibuf;
572 	struct imsg imsg;
573 	struct got_pathlist_head refs;
574 	struct got_pathlist_head delete_refs;
575 	struct got_pathlist_entry *pe;
576 	struct got_imsg_send_request send_req;
577 	struct got_imsg_send_ref href;
578 	size_t datalen, i;
579 #if 0
580 	static int attached;
581 	while (!attached)
582 		sleep (1);
583 #endif
584 
585 	TAILQ_INIT(&refs);
586 	TAILQ_INIT(&delete_refs);
587 
588 	imsg_init(&ibuf, GOT_IMSG_FD_CHILD);
589 #ifndef PROFILE
590 	/* revoke access to most system calls */
591 	if (pledge("stdio recvfd", NULL) == -1) {
592 		err = got_error_from_errno("pledge");
593 		got_privsep_send_error(&ibuf, err);
594 		return 1;
595 	}
596 
597 	/* revoke fs access */
598 	if (landlock_no_fs() == -1) {
599 		err = got_error_from_errno("landlock_no_fs");
600 		got_privsep_send_error(&ibuf, err);
601 		return 1;
602 	}
603 	if (cap_enter() == -1) {
604 		err = got_error_from_errno("cap_enter");
605 		got_privsep_send_error(&ibuf, err);
606 		return 1;
607 	}
608 #endif
609 	if ((err = got_privsep_recv_imsg(&imsg, &ibuf, 0)) != 0) {
610 		if (err->code == GOT_ERR_PRIVSEP_PIPE)
611 			err = NULL;
612 		goto done;
613 	}
614 	if (imsg.hdr.type == GOT_IMSG_STOP)
615 		goto done;
616 	if (imsg.hdr.type != GOT_IMSG_SEND_REQUEST) {
617 		err = got_error(GOT_ERR_PRIVSEP_MSG);
618 		goto done;
619 	}
620 	datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
621 	if (datalen < sizeof(send_req)) {
622 		err = got_error(GOT_ERR_PRIVSEP_LEN);
623 		goto done;
624 	}
625 	memcpy(&send_req, imsg.data, sizeof(send_req));
626 	sendfd = imsg.fd;
627 	imsg_free(&imsg);
628 
629 	if (send_req.verbosity > 0)
630 		chattygot += send_req.verbosity;
631 
632 	for (i = 0; i < send_req.nrefs; i++) {
633 		struct got_object_id *id;
634 		char *refname;
635 
636 		if ((err = got_privsep_recv_imsg(&imsg, &ibuf, 0)) != 0) {
637 			if (err->code == GOT_ERR_PRIVSEP_PIPE)
638 				err = NULL;
639 			goto done;
640 		}
641 		if (imsg.hdr.type == GOT_IMSG_STOP)
642 			goto done;
643 		if (imsg.hdr.type != GOT_IMSG_SEND_REF) {
644 			err = got_error(GOT_ERR_PRIVSEP_MSG);
645 			goto done;
646 		}
647 		datalen = imsg.hdr.len - IMSG_HEADER_SIZE;
648 		if (datalen < sizeof(href)) {
649 			err = got_error(GOT_ERR_PRIVSEP_LEN);
650 			goto done;
651 		}
652 		memcpy(&href, imsg.data, sizeof(href));
653 		if (datalen - sizeof(href) < href.name_len) {
654 			err = got_error(GOT_ERR_PRIVSEP_LEN);
655 			goto done;
656 		}
657 		refname = malloc(href.name_len + 1);
658 		if (refname == NULL) {
659 			err = got_error_from_errno("malloc");
660 			goto done;
661 		}
662 		memcpy(refname, imsg.data + sizeof(href), href.name_len);
663 		refname[href.name_len] = '\0';
664 
665 		/*
666 		 * Prevent sending of references that won't make any
667 		 * sense outside the local repository's context.
668 		 */
669 		if (strncmp(refname, "refs/got/", 9) == 0 ||
670 		    strncmp(refname, "refs/remotes/", 13) == 0) {
671 			err = got_error_fmt(GOT_ERR_SEND_BAD_REF,
672 			    "%s", refname);
673 			goto done;
674 		}
675 
676 		id = malloc(sizeof(*id));
677 		if (id == NULL) {
678 			free(refname);
679 			err = got_error_from_errno("malloc");
680 			goto done;
681 		}
682 		memcpy(id->sha1, href.id, SHA1_DIGEST_LENGTH);
683 		if (href.delete)
684 			err = got_pathlist_append(&delete_refs, refname, id);
685 		else
686 			err = got_pathlist_append(&refs, refname, id);
687 		if (err) {
688 			free(refname);
689 			free(id);
690 			goto done;
691 		}
692 
693 		imsg_free(&imsg);
694 	}
695 
696 	err = send_pack(sendfd, &refs, &delete_refs, &ibuf);
697 done:
698 	TAILQ_FOREACH(pe, &refs, entry) {
699 		free((char *)pe->path);
700 		free(pe->data);
701 	}
702 	got_pathlist_free(&refs);
703 	TAILQ_FOREACH(pe, &delete_refs, entry) {
704 		free((char *)pe->path);
705 		free(pe->data);
706 	}
707 	got_pathlist_free(&delete_refs);
708 	if (sendfd != -1 && close(sendfd) == -1 && err == NULL)
709 		err = got_error_from_errno("close");
710 	if (err != NULL && err->code != GOT_ERR_CANCELLED)  {
711 		fprintf(stderr, "%s: %s\n", getprogname(), err->msg);
712 		got_privsep_send_error(&ibuf, err);
713 	}
714 
715 	exit(0);
716 }