1 /*
2  * Copyright (c) 2018, 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/stat.h>
20 #include <sys/queue.h>
21 #include <sys/uio.h>
22 #include <sys/socket.h>
23 #include <sys/wait.h>
24 #include <sys/resource.h>
25 #include <sys/socket.h>
26 
27 #include <endian.h>
28 #include <errno.h>
29 #include <err.h>
30 #include <fcntl.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 #include <stdint.h>
35 #include <sha1.h>
36 #include <unistd.h>
37 #include <zlib.h>
38 #include <ctype.h>
39 #include <limits.h>
40 #include <imsg.h>
41 #include <time.h>
42 #include <uuid.h>
43 #include <netdb.h>
44 #include <netinet/in.h>
45 
46 #include "got_error.h"
47 #include "got_reference.h"
48 #include "got_repository.h"
49 #include "got_path.h"
50 #include "got_cancel.h"
51 #include "got_worktree.h"
52 #include "got_object.h"
53 #include "got_opentemp.h"
54 #include "got_send.h"
55 #include "got_repository_admin.h"
56 #include "got_commit_graph.h"
57 
58 #include "got_lib_delta.h"
59 #include "got_lib_inflate.h"
60 #include "got_lib_object.h"
61 #include "got_lib_object_parse.h"
62 #include "got_lib_object_create.h"
63 #include "got_lib_pack.h"
64 #include "got_lib_sha1.h"
65 #include "got_lib_privsep.h"
66 #include "got_lib_object_cache.h"
67 #include "got_lib_repository.h"
68 #include "got_lib_pack_create.h"
69 
70 #ifndef nitems
71 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
72 #endif
73 
74 #ifndef ssizeof
75 #define ssizeof(_x) ((ssize_t)(sizeof(_x)))
76 #endif
77 
78 #ifndef MIN
79 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
80 #endif
81 
82 static const struct got_error *
83 dial_ssh(pid_t *sendpid, int *sendfd, const char *host, const char *port,
84     const char *path, const char *direction, int verbosity)
85 {
86 	const struct got_error *error = NULL;
87 	int pid, pfd[2];
88 	char cmd[64];
89 	char *argv[11];
90 	int i = 0, j;
91 
92 	*sendpid = -1;
93 	*sendfd = -1;
94 
95 	argv[i++] = GOT_SEND_PATH_SSH;
96 	if (port != NULL) {
97 		argv[i++] = "-p";
98 		argv[i++] = (char *)port;
99 	}
100 	if (verbosity == -1) {
101 		argv[i++] = "-q";
102 	} else {
103 		/* ssh(1) allows up to 3 "-v" options. */
104 		for (j = 0; j < MIN(3, verbosity); j++)
105 			argv[i++] = "-v";
106 	}
107 	argv[i++] = "--";
108 	argv[i++] = (char *)host;
109 	argv[i++] = (char *)cmd;
110 	argv[i++] = (char *)path;
111 	argv[i++] = NULL;
112 
113 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, pfd) == -1)
114 		return got_error_from_errno("socketpair");
115 
116 	pid = fork();
117 	if (pid == -1) {
118 		error = got_error_from_errno("fork");
119 		close(pfd[0]);
120 		close(pfd[1]);
121 		return error;
122 	} else if (pid == 0) {
123 		int n;
124 		if (close(pfd[1]) == -1)
125 			err(1, "close");
126 		if (dup2(pfd[0], 0) == -1)
127 			err(1, "dup2");
128 		if (dup2(pfd[0], 1) == -1)
129 			err(1, "dup2");
130 		n = snprintf(cmd, sizeof(cmd), "git-%s-pack", direction);
131 		if (n < 0 || n >= ssizeof(cmd))
132 			err(1, "snprintf");
133 		if (execv(GOT_SEND_PATH_SSH, argv) == -1)
134 			err(1, "execv");
135 		abort(); /* not reached */
136 	} else {
137 		if (close(pfd[0]) == -1)
138 			return got_error_from_errno("close");
139 		*sendpid = pid;
140 		*sendfd = pfd[1];
141 		return NULL;
142 	}
143 }
144 
145 static const struct got_error *
146 dial_git(int *sendfd, const char *host, const char *port, const char *path,
147     const char *direction)
148 {
149 	const struct got_error *err = NULL;
150 	struct addrinfo hints, *servinfo, *p;
151 	char *cmd = NULL;
152 	int fd = -1, len, r, eaicode;
153 
154 	*sendfd = -1;
155 
156 	if (port == NULL)
157 		port = GOT_DEFAULT_GIT_PORT_STR;
158 
159 	memset(&hints, 0, sizeof hints);
160 	hints.ai_family = AF_UNSPEC;
161 	hints.ai_socktype = SOCK_STREAM;
162 	eaicode = getaddrinfo(host, port, &hints, &servinfo);
163 	if (eaicode) {
164 		char msg[512];
165 		snprintf(msg, sizeof(msg), "%s: %s", host,
166 		    gai_strerror(eaicode));
167 		return got_error_msg(GOT_ERR_ADDRINFO, msg);
168 	}
169 
170 	for (p = servinfo; p != NULL; p = p->ai_next) {
171 		if ((fd = socket(p->ai_family, p->ai_socktype,
172 		    p->ai_protocol)) == -1)
173 			continue;
174 		if (connect(fd, p->ai_addr, p->ai_addrlen) == 0) {
175 			err = NULL;
176 			break;
177 		}
178 		err = got_error_from_errno("connect");
179 		close(fd);
180 	}
181 	if (p == NULL)
182 		goto done;
183 
184 	if (asprintf(&cmd, "git-%s-pack %s", direction, path) == -1) {
185 		err = got_error_from_errno("asprintf");
186 		goto done;
187 	}
188 	len = 4 + strlen(cmd) + 1 + strlen("host=") + strlen(host) + 1;
189 	r = dprintf(fd, "%04x%s%chost=%s%c", len, cmd, '\0', host, '\0');
190 	if (r < 0)
191 		err = got_error_from_errno("dprintf");
192 done:
193 	free(cmd);
194 	if (err) {
195 		if (fd != -1)
196 			close(fd);
197 	} else
198 		*sendfd = fd;
199 	return err;
200 }
201 
202 const struct got_error *
203 got_send_connect(pid_t *sendpid, int *sendfd, const char *proto,
204     const char *host, const char *port, const char *server_path, int verbosity)
205 {
206 	const struct got_error *err = NULL;
207 
208 	*sendpid = -1;
209 	*sendfd = -1;
210 
211 	if (strcmp(proto, "ssh") == 0 || strcmp(proto, "git+ssh") == 0)
212 		err = dial_ssh(sendpid, sendfd, host, port, server_path,
213 		    "receive", verbosity);
214 	else if (strcmp(proto, "git") == 0)
215 		err = dial_git(sendfd, host, port, server_path, "receive");
216 	else if (strcmp(proto, "http") == 0 || strcmp(proto, "git+http") == 0)
217 		err = got_error_path(proto, GOT_ERR_NOT_IMPL);
218 	else
219 		err = got_error_path(proto, GOT_ERR_BAD_PROTO);
220 	return err;
221 }
222 
223 struct pack_progress_arg {
224     got_send_progress_cb progress_cb;
225     void *progress_arg;
226 
227     off_t packfile_size;
228     int ncommits;
229     int nobj_total;
230     int nobj_deltify;
231     int nobj_written;
232 };
233 
234 static const struct got_error *
235 pack_progress(void *arg, off_t packfile_size, int ncommits,
236     int nobj_total, int nobj_deltify, int nobj_written)
237 {
238 	const struct got_error *err;
239 	struct pack_progress_arg *a = arg;
240 
241 	err = a->progress_cb(a->progress_arg, packfile_size, ncommits,
242 	    nobj_total, nobj_deltify, nobj_written, 0, NULL, 0);
243 	if (err)
244 		return err;
245 
246 	a->packfile_size = packfile_size;
247 	a->ncommits = ncommits;
248 	a->nobj_total = nobj_total;
249 	a->nobj_deltify = nobj_deltify;
250 	a->nobj_written = nobj_written;
251 	return NULL;
252 }
253 
254 static const struct got_error *
255 insert_ref(struct got_reflist_head *refs, const char *refname,
256     struct got_repository *repo)
257 {
258 	const struct got_error *err;
259 	struct got_reference *ref;
260 	struct got_reflist_entry *new;
261 
262 	err = got_ref_open(&ref, repo, refname, 0);
263 	if (err)
264 		return err;
265 
266 	err = got_reflist_insert(&new, refs, ref, got_ref_cmp_by_name, NULL);
267 	if (err || new == NULL /* duplicate */)
268 		got_ref_close(ref);
269 
270 	return err;
271 }
272 
273 static const struct got_error *
274 check_linear_ancestry(const char *refname, struct got_object_id *my_id,
275     struct got_object_id *their_id, struct got_repository *repo,
276     got_cancel_cb cancel_cb, void *cancel_arg)
277 {
278 	const struct got_error *err = NULL;
279 	struct got_object_id *yca_id;
280 	int obj_type;
281 
282 	err = got_object_get_type(&obj_type, repo, their_id);
283 	if (err)
284 		return err;
285 	if (obj_type != GOT_OBJ_TYPE_COMMIT)
286 		return got_error_fmt(GOT_ERR_OBJ_TYPE,
287 		    "bad object type on server for %s", refname);
288 
289 	err = got_commit_graph_find_youngest_common_ancestor(&yca_id,
290 	    my_id, their_id, repo, cancel_cb, cancel_arg);
291 	if (err)
292 		return err;
293 	if (yca_id == NULL)
294 		return got_error_fmt(GOT_ERR_SEND_ANCESTRY, "%s", refname);
295 
296 	/*
297 	 * Require a straight line of history between the two commits,
298 	 * with their commit being older than my commit.
299 	 *
300 	 * Non-linear situations such as this require a rebase:
301 	 *
302 	 * (theirs) D       F (mine)
303 	 *           \     /
304 	 *            C   E
305 	 *             \ /
306 	 *              B (yca)
307 	 *              |
308 	 *              A
309 	 */
310 	if (got_object_id_cmp(their_id, yca_id) != 0)
311 		err = got_error_fmt(GOT_ERR_SEND_ANCESTRY, "%s", refname);
312 
313 	free(yca_id);
314 	return err;
315 }
316 
317 static const struct got_error *
318 realloc_ids(struct got_object_id ***ids, size_t *nalloc, size_t n)
319 {
320 	struct got_object_id **new;
321 	const size_t alloc_chunksz = 256;
322 
323 	if (*nalloc >= n)
324 		return NULL;
325 
326 	new = recallocarray(*ids, *nalloc, *nalloc + alloc_chunksz,
327 	    sizeof(struct got_object_id));
328 	if (new == NULL)
329 		return got_error_from_errno("recallocarray");
330 
331 	*ids = new;
332 	*nalloc += alloc_chunksz;
333 	return NULL;
334 }
335 
336 static struct got_reference *
337 find_ref(struct got_reflist_head *refs, const char *refname)
338 {
339 	struct got_reflist_entry *re;
340 
341 	TAILQ_FOREACH(re, refs, entry) {
342 		if (got_path_cmp(got_ref_get_name(re->ref), refname,
343 		    strlen(got_ref_get_name(re->ref)),
344 		    strlen(refname)) == 0) {
345 			return re->ref;
346 		}
347 	}
348 
349 	return NULL;
350 }
351 
352 static struct got_pathlist_entry *
353 find_their_ref(struct got_pathlist_head *their_refs, const char *refname)
354 {
355 	struct got_pathlist_entry *pe;
356 
357 	TAILQ_FOREACH(pe, their_refs, entry) {
358 		const char *their_refname = pe->path;
359 		if (got_path_cmp(their_refname, refname,
360 		    strlen(their_refname), strlen(refname)) == 0) {
361 			return pe;
362 		}
363 	}
364 
365 	return NULL;
366 }
367 
368 static const struct got_error *
369 get_remote_refname(char **remote_refname, const char *remote_name,
370     const char *refname)
371 {
372 	if (strncmp(refname, "refs/", 5) == 0)
373 		refname += 5;
374 	if (strncmp(refname, "heads/", 6) == 0)
375 		refname += 6;
376 
377 	if (asprintf(remote_refname, "refs/remotes/%s/%s",
378 	    remote_name, refname) == -1)
379 		return got_error_from_errno("asprintf");
380 
381 	return NULL;
382 }
383 
384 static const struct got_error *
385 update_remote_ref(struct got_reference *my_ref, const char *remote_name,
386     struct got_repository *repo)
387 {
388 	const struct got_error *err, *unlock_err;
389 	struct got_object_id *my_id;
390 	struct got_reference *ref = NULL;
391 	char *remote_refname = NULL;
392 	int ref_locked = 0;
393 
394 	err = got_ref_resolve(&my_id, repo, my_ref);
395 	if (err)
396 		return err;
397 
398 	err = get_remote_refname(&remote_refname, remote_name,
399 	    got_ref_get_name(my_ref));
400 	if (err)
401 		goto done;
402 
403 	err = got_ref_open(&ref, repo, remote_refname, 1 /* lock */);
404 	if (err) {
405 		if (err->code != GOT_ERR_NOT_REF)
406 			goto done;
407 		err = got_ref_alloc(&ref, remote_refname, my_id);
408 		if (err)
409 			goto done;
410 	} else {
411 		ref_locked = 1;
412 		err = got_ref_change_ref(ref, my_id);
413 		if (err)
414 			goto done;
415 	}
416 
417 	err = got_ref_write(ref, repo);
418 done:
419 	if (ref) {
420 		if (ref_locked) {
421 			unlock_err = got_ref_unlock(ref);
422 			if (unlock_err && err == NULL)
423 				err = unlock_err;
424 		}
425 		got_ref_close(ref);
426 	}
427 	free(my_id);
428 	free(remote_refname);
429 	return err;
430 }
431 
432 const struct got_error*
433 got_send_pack(const char *remote_name, struct got_pathlist_head *branch_names,
434     struct got_pathlist_head *tag_names,
435     struct got_pathlist_head *delete_branches,
436     int verbosity, int overwrite_refs, int sendfd,
437     struct got_repository *repo, got_send_progress_cb progress_cb,
438     void *progress_arg, got_cancel_cb cancel_cb, void *cancel_arg)
439 {
440 	int imsg_sendfds[2];
441 	int npackfd = -1, nsendfd = -1;
442 	int sendstatus, done = 0;
443 	const struct got_error *err;
444 	struct imsgbuf sendibuf;
445 	pid_t sendpid = -1;
446 	struct got_reflist_head refs;
447 	struct got_pathlist_head have_refs;
448 	struct got_pathlist_head their_refs;
449 	struct got_pathlist_entry *pe;
450 	struct got_reflist_entry *re;
451 	struct got_object_id **our_ids = NULL;
452 	struct got_object_id **their_ids = NULL;
453 	struct got_object_id *my_id = NULL;
454 	int i, nours = 0, ntheirs = 0;
455 	size_t nalloc_ours = 0, nalloc_theirs = 0;
456 	int refs_to_send = 0, refs_to_delete = 0;
457 	off_t bytes_sent = 0;
458 	struct pack_progress_arg ppa;
459 	uint8_t packsha1[SHA1_DIGEST_LENGTH];
460 	FILE *packfile = NULL;
461 
462 	TAILQ_INIT(&refs);
463 	TAILQ_INIT(&have_refs);
464 	TAILQ_INIT(&their_refs);
465 
466 	TAILQ_FOREACH(pe, branch_names, entry) {
467 		const char *branchname = pe->path;
468 		if (strncmp(branchname, "refs/heads/", 11) != 0) {
469 			char *s;
470 			if (asprintf(&s, "refs/heads/%s", branchname) == -1) {
471 				err = got_error_from_errno("asprintf");
472 				goto done;
473 			}
474 			err = insert_ref(&refs, s, repo);
475 			free(s);
476 		} else {
477 			err = insert_ref(&refs, branchname, repo);
478 		}
479 		if (err)
480 			goto done;
481 	}
482 
483 	TAILQ_FOREACH(pe, delete_branches, entry) {
484 		const char *branchname = pe->path;
485 		struct got_reference *ref;
486 		if (strncmp(branchname, "refs/heads/", 11) != 0) {
487 			err = got_error_fmt(GOT_ERR_SEND_DELETE_REF, "%s",
488 			    branchname);
489 			goto done;
490 		}
491 		ref = find_ref(&refs, branchname);
492 		if (ref) {
493 			err = got_error_fmt(GOT_ERR_SEND_DELETE_REF,
494 			    "changes on %s will be sent to server",
495 			    branchname);
496 			goto done;
497 		}
498 	}
499 
500 	TAILQ_FOREACH(pe, tag_names, entry) {
501 		const char *tagname = pe->path;
502 		if (strncmp(tagname, "refs/tags/", 10) != 0) {
503 			char *s;
504 			if (asprintf(&s, "refs/tags/%s", tagname) == -1) {
505 				err = got_error_from_errno("asprintf");
506 				goto done;
507 			}
508 			err = insert_ref(&refs, s, repo);
509 			free(s);
510 		} else {
511 			err = insert_ref(&refs, tagname, repo);
512 		}
513 		if (err)
514 			goto done;
515 	}
516 
517 	if (TAILQ_EMPTY(&refs) && TAILQ_EMPTY(delete_branches)) {
518 		err = got_error(GOT_ERR_SEND_EMPTY);
519 		goto done;
520 	}
521 
522 	TAILQ_FOREACH(re, &refs, entry) {
523 		struct got_object_id *id;
524 		int obj_type;
525 
526 		if (got_ref_is_symbolic(re->ref)) {
527 			err = got_error_fmt(GOT_ERR_BAD_REF_TYPE,
528 			    "cannot send symbolic reference %s",
529 			    got_ref_get_name(re->ref));
530 			goto done;
531 		}
532 
533 		err = got_ref_resolve(&id, repo, re->ref);
534 		if (err)
535 			goto done;
536 		err = got_object_get_type(&obj_type, repo, id);
537 		free(id);
538 		if (err)
539 			goto done;
540 		switch (obj_type) {
541 		case GOT_OBJ_TYPE_COMMIT:
542 		case GOT_OBJ_TYPE_TAG:
543 			break;
544 		default:
545 			err = got_error_fmt(GOT_ERR_OBJ_TYPE,
546 			    "cannot send %s", got_ref_get_name(re->ref));
547 			goto done;
548 		}
549 	}
550 
551 	packfile = got_opentemp();
552 	if (packfile == NULL) {
553 		err = got_error_from_errno("got_opentemp");
554 		goto done;
555 	}
556 
557 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_sendfds) == -1) {
558 		err = got_error_from_errno("socketpair");
559 		goto done;
560 	}
561 
562 	sendpid = fork();
563 	if (sendpid == -1) {
564 		err = got_error_from_errno("fork");
565 		goto done;
566 	} else if (sendpid == 0){
567 		got_privsep_exec_child(imsg_sendfds,
568 		    GOT_PATH_PROG_SEND_PACK, got_repo_get_path(repo));
569 	}
570 
571 	if (close(imsg_sendfds[1]) == -1) {
572 		err = got_error_from_errno("close");
573 		goto done;
574 	}
575 	imsg_init(&sendibuf, imsg_sendfds[0]);
576 	nsendfd = dup(sendfd);
577 	if (nsendfd == -1) {
578 		err = got_error_from_errno("dup");
579 		goto done;
580 	}
581 
582 	/*
583 	 * Convert reflist to pathlist since the privsep layer
584 	 * is linked into helper programs which lack reference.c.
585 	 */
586 	TAILQ_FOREACH(re, &refs, entry) {
587 		struct got_object_id *id;
588 		err = got_ref_resolve(&id, repo, re->ref);
589 		if (err)
590 			goto done;
591 		err = got_pathlist_append(&have_refs,
592 		    got_ref_get_name(re->ref), id);
593 		if (err)
594 			goto done;
595 		/*
596 		 * Also prepare the array of our object IDs which
597 		 * will be needed for generating a pack file.
598 		 */
599 		err = realloc_ids(&our_ids, &nalloc_ours, nours + 1);
600 		if (err)
601 			goto done;
602 		our_ids[nours] = id;
603 		nours++;
604 	}
605 
606 	err = got_privsep_send_send_req(&sendibuf, nsendfd, &have_refs,
607 	    delete_branches, verbosity);
608 	if (err)
609 		goto done;
610 	nsendfd = -1;
611 
612 	err = got_privsep_recv_send_remote_refs(&their_refs, &sendibuf);
613 	if (err)
614 		goto done;
615 
616 	/*
617 	 * Process references reported by the server.
618 	 * Push appropriate object IDs onto the "their IDs" array.
619 	 * This array will be used to exclude objects which already
620 	 * exist on the server from our pack file.
621 	 */
622 	TAILQ_FOREACH(pe, &their_refs, entry) {
623 		const char *refname = pe->path;
624 		struct got_object_id *their_id = pe->data;
625 		int have_their_id;
626 		struct got_object *obj;
627 		struct got_reference *my_ref = NULL;
628 		int is_tag = 0;
629 
630 		/* Don't blindly trust the server to send us valid names. */
631 		if (!got_ref_name_is_valid(refname))
632 			continue;
633 
634 		/*
635 		 * Find out whether this is a reference we want to upload.
636 		 * Otherwise we can still use this reference as a hint to
637 		 * avoid uploading any objects the server already has.
638 		 */
639 		my_ref = find_ref(&refs, refname);
640 		if (my_ref) {
641 			err = got_ref_resolve(&my_id, repo, my_ref);
642 			if (err)
643 				goto done;
644 			if (got_object_id_cmp(my_id, their_id) == 0) {
645 				free(my_id);
646 				my_id = NULL;
647 				continue;
648 			}
649 			refs_to_send++;
650 
651 		}
652 
653 		if (strncmp(refname, "refs/tags/", 10) == 0)
654 			is_tag = 1;
655 
656 		/* Prevent tags from being overwritten by default. */ 
657 		if (!overwrite_refs && my_ref && is_tag) {
658 			err = got_error_fmt(GOT_ERR_SEND_TAG_EXISTS,
659 			    "%s", refname);
660 			goto done;
661 		}
662 
663 		/* Check if their object exists locally. */
664 		err = got_object_open(&obj, repo, their_id);
665 		if (err) {
666 			if (err->code != GOT_ERR_NO_OBJ)
667 				goto done;
668 			if (!overwrite_refs && my_ref != NULL) {
669 				err = got_error_fmt(GOT_ERR_SEND_ANCESTRY,
670 				    "%s", refname);
671 				goto done;
672 			}
673 			have_their_id = 0;
674 		} else {
675 			got_object_close(obj);
676 			have_their_id = 1;
677 		}
678 
679 		err = realloc_ids(&their_ids, &nalloc_theirs, ntheirs + 1);
680 		if (err)
681 			goto done;
682 
683 		if (have_their_id) {
684 			/* Enforce linear ancestry if required. */
685 			if (!overwrite_refs && my_ref && !is_tag) {
686 				struct got_object_id *my_id;
687 				err = got_ref_resolve(&my_id, repo, my_ref);
688 				if (err)
689 					goto done;
690 				err = check_linear_ancestry(refname, my_id,
691 				    their_id, repo, cancel_cb, cancel_arg);
692 				free(my_id);
693 				my_id = NULL;
694 				if (err)
695 					goto done;
696 			}
697 			/* Exclude any objects reachable via their ID. */
698 			their_ids[ntheirs] = got_object_id_dup(their_id);
699 			if (their_ids[ntheirs] == NULL) {
700 				err = got_error_from_errno("got_object_id_dup");
701 				goto done;
702 			}
703 			ntheirs++;
704 		} else if (!is_tag) {
705 			char *remote_refname;
706 			struct got_reference *ref;
707 			/*
708 			 * Exclude any objects which exist on the server
709 			 * according to a locally cached remote reference.
710 			 */
711 			err = get_remote_refname(&remote_refname,
712 			    remote_name, refname);
713 			if (err)
714 				goto done;
715 			err = got_ref_open(&ref, repo, remote_refname, 0);
716 			free(remote_refname);
717 			if (err) {
718 				if (err->code != GOT_ERR_NOT_REF)
719 					goto done;
720 			} else {
721 				err = got_ref_resolve(&their_ids[ntheirs],
722 				    repo, ref);
723 				got_ref_close(ref);
724 				if (err)
725 					goto done;
726 				ntheirs++;
727 			}
728 		}
729 	}
730 
731 	/* Account for any new references we are going to upload. */
732 	TAILQ_FOREACH(re, &refs, entry) {
733 		if (find_their_ref(&their_refs,
734 		    got_ref_get_name(re->ref)) == NULL)
735 			refs_to_send++;
736 	}
737 
738 	/* Account for any existing references we are going to delete. */
739 	TAILQ_FOREACH(pe, delete_branches, entry) {
740 		const char *branchname = pe->path;
741 		if (find_their_ref(&their_refs, branchname))
742 			refs_to_delete++;
743 	}
744 
745 	if (refs_to_send == 0 && refs_to_delete == 0) {
746 		got_privsep_send_stop(imsg_sendfds[0]);
747 		goto done;
748 	}
749 
750 	if (refs_to_send > 0) {
751 		memset(&ppa, 0, sizeof(ppa));
752 		ppa.progress_cb = progress_cb;
753 		ppa.progress_arg = progress_arg;
754 		err = got_pack_create(packsha1, packfile, their_ids, ntheirs,
755 		    our_ids, nours, repo, 0, 1, pack_progress, &ppa,
756 		    cancel_cb, cancel_arg);
757 		if (err)
758 			goto done;
759 
760 		if (fflush(packfile) == -1) {
761 			err = got_error_from_errno("fflush");
762 			goto done;
763 		}
764 
765 		npackfd = dup(fileno(packfile));
766 		if (npackfd == -1) {
767 			err = got_error_from_errno("dup");
768 			goto done;
769 		}
770 		err = got_privsep_send_packfd(&sendibuf, npackfd);
771 		if (err != NULL)
772 			goto done;
773 		npackfd = -1;
774 	} else {
775 		err = got_privsep_send_packfd(&sendibuf, -1);
776 		if (err != NULL)
777 			goto done;
778 	}
779 
780 	while (!done) {
781 		int success = 0;
782 		char *refname = NULL;
783 		off_t bytes_sent_cur = 0;
784 		if (cancel_cb) {
785 			err = (*cancel_cb)(cancel_arg);
786 			if (err)
787 				goto done;
788 		}
789 		err = got_privsep_recv_send_progress(&done, &bytes_sent,
790 		    &success, &refname, &sendibuf);
791 		if (err)
792 			goto done;
793 		if (refname && got_ref_name_is_valid(refname) && success &&
794 		    strncmp(refname, "refs/tags/", 10) != 0) {
795 			struct got_reference *my_ref;
796 			/*
797 			 * The server has accepted our changes.
798 			 * Update our reference in refs/remotes/ accordingly.
799 			 */
800 			my_ref = find_ref(&refs, refname);
801 			if (my_ref) {
802 				err = update_remote_ref(my_ref, remote_name,
803 				    repo);
804 				if (err)
805 					goto done;
806 			}
807 		}
808 		if (refname != NULL ||
809 		    bytes_sent_cur != bytes_sent) {
810 			err = progress_cb(progress_arg, ppa.packfile_size,
811 			    ppa.ncommits, ppa.nobj_total, ppa.nobj_deltify,
812 			    ppa.nobj_written, bytes_sent,
813 			    refname, success);
814 			if (err) {
815 				free(refname);
816 				goto done;
817 			}
818 			bytes_sent_cur = bytes_sent;
819 		}
820 		free(refname);
821 	}
822 done:
823 	if (sendpid != -1) {
824 		if (err)
825 			got_privsep_send_stop(imsg_sendfds[0]);
826 		if (waitpid(sendpid, &sendstatus, 0) == -1 && err == NULL)
827 			err = got_error_from_errno("waitpid");
828 	}
829 	if (packfile && fclose(packfile) == EOF && err == NULL)
830 		err = got_error_from_errno("fclose");
831 	if (nsendfd != -1 && close(nsendfd) == -1 && err == NULL)
832 		err = got_error_from_errno("close");
833 	if (npackfd != -1 && close(npackfd) == -1 && err == NULL)
834 		err = got_error_from_errno("close");
835 
836 	got_ref_list_free(&refs);
837 	got_pathlist_free(&have_refs);
838 	got_pathlist_free(&their_refs);
839 	for (i = 0; i < nours; i++)
840 		free(our_ids[i]);
841 	free(our_ids);
842 	for (i = 0; i < ntheirs; i++)
843 		free(their_ids[i]);
844 	free(their_ids);
845 	free(my_id);
846 	return err;
847 }