1 /*
2  * Copyright (c) 2018, 2019 Ori Bernstein <ori@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/stat.h>
19 #include <sys/queue.h>
20 #include <sys/uio.h>
21 #include <sys/socket.h>
22 #include <sys/wait.h>
23 #include <sys/resource.h>
24 #include <sys/socket.h>
25 
26 #include <endian.h>
27 #include <errno.h>
28 #include <err.h>
29 #include <fcntl.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 #include <stdint.h>
34 #include <sha1.h>
35 #include <unistd.h>
36 #include <zlib.h>
37 #include <ctype.h>
38 #include <limits.h>
39 #include <imsg.h>
40 #include <time.h>
41 #include <uuid.h>
42 #include <netdb.h>
43 #include <netinet/in.h>
44 
45 #include "got_error.h"
46 #include "got_reference.h"
47 #include "got_repository.h"
48 #include "got_path.h"
49 #include "got_cancel.h"
50 #include "got_worktree.h"
51 #include "got_object.h"
52 #include "got_opentemp.h"
53 #include "got_fetch.h"
54 
55 #include "got_lib_delta.h"
56 #include "got_lib_inflate.h"
57 #include "got_lib_object.h"
58 #include "got_lib_object_parse.h"
59 #include "got_lib_object_create.h"
60 #include "got_lib_pack.h"
61 #include "got_lib_sha1.h"
62 #include "got_lib_privsep.h"
63 #include "got_lib_object_cache.h"
64 #include "got_lib_repository.h"
65 
66 #ifndef nitems
67 #define nitems(_a)	(sizeof((_a)) / sizeof((_a)[0]))
68 #endif
69 
70 #ifndef MIN
71 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
72 #endif
73 
74 static int
75 hassuffix(char *base, char *suf)
76 {
77 	int nb, ns;
78 
79 	nb = strlen(base);
80 	ns = strlen(suf);
81 	if (ns <= nb && strcmp(base + (nb - ns), suf) == 0)
82 		return 1;
83 	return 0;
84 }
85 
86 static const struct got_error *
87 dial_ssh(pid_t *fetchpid, int *fetchfd, const char *host, const char *port,
88     const char *path, const char *direction, int verbosity)
89 {
90 	const struct got_error *error = NULL;
91 	int pid, pfd[2];
92 	char cmd[64];
93 	char *argv[11];
94 	int i = 0, j;
95 
96 	*fetchpid = -1;
97 	*fetchfd = -1;
98 
99 	argv[i++] = GOT_FETCH_PATH_SSH;
100 	if (port != NULL) {
101 		argv[i++] = "-p";
102 		argv[i++] = (char *)port;
103 	}
104 	if (verbosity == -1) {
105 		argv[i++] = "-q";
106 	} else {
107 		/* ssh(1) allows up to 3 "-v" options. */
108 		for (j = 0; j < MIN(3, verbosity); j++)
109 			argv[i++] = "-v";
110 	}
111 	argv[i++] = "--";
112 	argv[i++] = (char *)host;
113 	argv[i++] = (char *)cmd;
114 	argv[i++] = (char *)path;
115 	argv[i++] = NULL;
116 
117 	if (pipe(pfd) == -1)
118 		return got_error_from_errno("pipe");
119 
120 	pid = fork();
121 	if (pid == -1) {
122 		error = got_error_from_errno("fork");
123 		close(pfd[0]);
124 		close(pfd[1]);
125 		return error;
126 	} else if (pid == 0) {
127 		int n;
128 		close(pfd[1]);
129 		dup2(pfd[0], 0);
130 		dup2(pfd[0], 1);
131 		n = snprintf(cmd, sizeof(cmd), "git-%s-pack", direction);
132 		if (n < 0 || n >= sizeof(cmd))
133 			err(1, "snprintf");
134 		if (execv(GOT_FETCH_PATH_SSH, argv) == -1)
135 			err(1, "execl");
136 		abort(); /* not reached */
137 	} else {
138 		close(pfd[0]);
139 		*fetchpid = pid;
140 		*fetchfd = pfd[1];
141 		return NULL;
142 	}
143 }
144 
145 static const struct got_error *
146 dial_git(int *fetchfd, 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, *pkt = NULL;
152 	int fd = -1, totlen, r, eaicode;
153 
154 	*fetchfd = -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 	totlen = 4 + strlen(cmd) + 1 + strlen("host=") + strlen(host) + 1;
189 	if (asprintf(&pkt, "%04x%s", totlen, cmd) == -1) {
190 		err = got_error_from_errno("asprintf");
191 		goto done;
192 	}
193 	r = write(fd, pkt, strlen(pkt) + 1);
194 	if (r == -1) {
195 		err = got_error_from_errno("write");
196 		goto done;
197 	}
198 	if (asprintf(&pkt, "host=%s", host) == -1) {
199 		err = got_error_from_errno("asprintf");
200 		goto done;
201 	}
202 	r = write(fd, pkt, strlen(pkt) + 1);
203 	if (r == -1) {
204 		err = got_error_from_errno("write");
205 		goto done;
206 	}
207 done:
208 	free(cmd);
209 	free(pkt);
210 	if (err) {
211 		if (fd != -1)
212 			close(fd);
213 	} else
214 		*fetchfd = fd;
215 	return err;
216 }
217 
218 const struct got_error *
219 got_fetch_connect(pid_t *fetchpid, int *fetchfd, const char *proto,
220     const char *host, const char *port, const char *server_path, int verbosity)
221 {
222 	const struct got_error *err = NULL;
223 
224 	*fetchpid = -1;
225 	*fetchfd = -1;
226 
227 	if (strcmp(proto, "ssh") == 0 || strcmp(proto, "git+ssh") == 0)
228 		err = dial_ssh(fetchpid, fetchfd, host, port, server_path,
229 		    "upload", verbosity);
230 	else if (strcmp(proto, "git") == 0)
231 		err = dial_git(fetchfd, host, port, server_path, "upload");
232 	else if (strcmp(proto, "http") == 0 || strcmp(proto, "git+http") == 0)
233 		err = got_error_path(proto, GOT_ERR_NOT_IMPL);
234 	else
235 		err = got_error_path(proto, GOT_ERR_BAD_PROTO);
236 	return err;
237 }
238 
239 const struct got_error *
240 got_fetch_parse_uri(char **proto, char **host, char **port,
241     char **server_path, char **repo_name, const char *uri)
242 {
243 	const struct got_error *err = NULL;
244 	char *s, *p, *q;
245 	int n;
246 
247 	*proto = *host = *port = *server_path = *repo_name = NULL;
248 
249 	p = strstr(uri, "://");
250 	if (!p) {
251 		/* Try parsing Git's "scp" style URL syntax. */
252 		*proto = strdup("ssh");
253 		if (proto == NULL) {
254 			err = got_error_from_errno("strdup");
255 			goto done;
256 		}
257 		s = (char *)uri;
258 		q = strchr(s, ':');
259 		if (q == NULL) {
260 			err = got_error(GOT_ERR_PARSE_URI);
261 			goto done;
262 		}
263 		/* No slashes allowed before first colon. */
264 		p = strchr(s, '/');
265 		if (p && q > p) {
266 			err = got_error(GOT_ERR_PARSE_URI);
267 			goto done;
268 		}
269 		*host = strndup(s, q - s);
270 		if (*host == NULL) {
271 			err = got_error_from_errno("strndup");
272 			goto done;
273 		}
274 		p = q + 1;
275 	} else {
276 		*proto = strndup(uri, p - uri);
277 		if (proto == NULL) {
278 			err = got_error_from_errno("strndup");
279 			goto done;
280 		}
281 		s = p + 3;
282 
283 		p = strstr(s, "/");
284 		if (p == NULL || strlen(p) == 1) {
285 			err = got_error(GOT_ERR_PARSE_URI);
286 			goto done;
287 		}
288 
289 		q = memchr(s, ':', p - s);
290 		if (q) {
291 			*host = strndup(s, q - s);
292 			if (*host == NULL) {
293 				err = got_error_from_errno("strndup");
294 				goto done;
295 			}
296 			*port = strndup(q + 1, p - (q + 1));
297 			if (*port == NULL) {
298 				err = got_error_from_errno("strndup");
299 				goto done;
300 			}
301 		} else {
302 			*host = strndup(s, p - s);
303 			if (*host == NULL) {
304 				err = got_error_from_errno("strndup");
305 				goto done;
306 			}
307 		}
308 	}
309 
310 	while (p[0] == '/' && p[1] == '/')
311 		p++;
312 	*server_path = strdup(p);
313 	if (*server_path == NULL) {
314 		err = got_error_from_errno("strdup");
315 		goto done;
316 	}
317 	got_path_strip_trailing_slashes(*server_path);
318 
319 	p = strrchr(p, '/');
320 	if (!p || strlen(p) <= 1) {
321 		err = got_error(GOT_ERR_PARSE_URI);
322 		goto done;
323 	}
324 	p++;
325 	n = strlen(p);
326 	if (n == 0) {
327 		err = got_error(GOT_ERR_PARSE_URI);
328 		goto done;
329 	}
330 	if (hassuffix(p, ".git"))
331 		n -= 4;
332 	*repo_name = strndup(p, (p + n) - p);
333 	if (*repo_name == NULL) {
334 		err = got_error_from_errno("strndup");
335 		goto done;
336 	}
337 done:
338 	if (err) {
339 		free(*proto);
340 		*proto = NULL;
341 		free(*host);
342 		*host = NULL;
343 		free(*port);
344 		*port = NULL;
345 		free(*server_path);
346 		*server_path = NULL;
347 		free(*repo_name);
348 		*repo_name = NULL;
349 	}
350 	return err;
351 }
352 
353 const struct got_error*
354 got_fetch_pack(struct got_object_id **pack_hash, struct got_pathlist_head *refs,
355     struct got_pathlist_head *symrefs, const char *remote_name,
356     int mirror_references, int fetch_all_branches,
357     struct got_pathlist_head *wanted_branches,
358     struct got_pathlist_head *wanted_refs, int list_refs_only, int verbosity,
359     int fetchfd, struct got_repository *repo,
360     got_fetch_progress_cb progress_cb, void *progress_arg)
361 {
362 	int imsg_fetchfds[2], imsg_idxfds[2];
363 	int packfd = -1, npackfd = -1, idxfd = -1, nidxfd = -1, nfetchfd = -1;
364 	int tmpfds[3], i;
365 	int fetchstatus, idxstatus, done = 0;
366 	const struct got_error *err;
367 	struct imsgbuf fetchibuf, idxibuf;
368 	pid_t fetchpid, idxpid;
369 	char *tmppackpath = NULL, *tmpidxpath = NULL;
370 	char *packpath = NULL, *idxpath = NULL, *id_str = NULL;
371 	const char *repo_path = NULL;
372 	struct got_pathlist_head have_refs;
373 	struct got_pathlist_entry *pe;
374 	struct got_reflist_head my_refs;
375 	struct got_reflist_entry *re;
376 	off_t packfile_size = 0;
377 	struct got_packfile_hdr pack_hdr;
378 	uint32_t nobj = 0;
379 	char *ref_prefix = NULL;
380 	size_t ref_prefixlen = 0;
381 	char *path;
382 	char *progress = NULL;
383 
384 	*pack_hash = NULL;
385 
386 	/*
387 	 * Prevent fetching of references that won't make any
388 	 * sense outside of the remote repository's context.
389 	 */
390 	TAILQ_FOREACH(pe, wanted_refs, entry) {
391 		const char *refname = pe->path;
392 		if (strncmp(refname, "refs/got/", 9) == 0 ||
393 		    strncmp(refname, "got/", 4) == 0 ||
394 		    strncmp(refname, "refs/remotes/", 13) == 0 ||
395 		    strncmp(refname, "remotes/", 8) == 0)
396 			return got_error_path(refname, GOT_ERR_FETCH_BAD_REF);
397 	}
398 
399 	if (!list_refs_only)
400 		repo_path = got_repo_get_path_git_dir(repo);
401 
402 	for (i = 0; i < nitems(tmpfds); i++)
403 		tmpfds[i] = -1;
404 
405 	TAILQ_INIT(&have_refs);
406 	SIMPLEQ_INIT(&my_refs);
407 
408 	if (!mirror_references) {
409 		if (asprintf(&ref_prefix, "refs/remotes/%s/",
410 		    remote_name) == -1)
411 			return got_error_from_errno("asprintf");
412 		ref_prefixlen = strlen(ref_prefix);
413 	}
414 
415 	if (!list_refs_only) {
416 		err = got_ref_list(&my_refs, repo, NULL,
417 		    got_ref_cmp_by_name, NULL);
418 		if (err)
419 			goto done;
420 	}
421 
422 	SIMPLEQ_FOREACH(re, &my_refs, entry) {
423 		struct got_object_id *id;
424 		const char *refname;
425 
426 		if (got_ref_is_symbolic(re->ref))
427 			continue;
428 
429 		refname = got_ref_get_name(re->ref);
430 
431 		if (mirror_references) {
432 			char *name;
433 			err = got_ref_resolve(&id, repo, re->ref);
434 			if (err)
435 				goto done;
436 			name = strdup(refname);
437 			if (name == NULL) {
438 				err = got_error_from_errno("strdup");
439 				goto done;
440 			}
441 			err = got_pathlist_append(&have_refs, name, id);
442 			if (err)
443 				goto done;
444 			continue;
445 		}
446 
447 		if (strncmp("refs/tags/", refname, 10) == 0) {
448 			char *tagname;
449 
450 			err = got_ref_resolve(&id, repo, re->ref);
451 			if (err)
452 				goto done;
453 			tagname = strdup(refname);
454 			if (tagname == NULL) {
455 				err = got_error_from_errno("strdup");
456 				goto done;
457 			}
458 			err = got_pathlist_append(&have_refs, tagname, id);
459 			if (err) {
460 				free(tagname);
461 				goto done;
462 			}
463 		}
464 
465 		if (strncmp(ref_prefix, refname, ref_prefixlen) == 0) {
466 			char *branchname;
467 
468 			err = got_ref_resolve(&id, repo, re->ref);
469 			if (err)
470 				goto done;
471 
472 			if (asprintf(&branchname, "refs/heads/%s",
473 			    refname + ref_prefixlen) == -1) {
474 				err = got_error_from_errno("asprintf");
475 				goto done;
476 			}
477 			err = got_pathlist_append(&have_refs, branchname, id);
478 			if (err) {
479 				free(branchname);
480 				goto done;
481 			}
482 		}
483 	}
484 
485 	if (list_refs_only) {
486 		packfd = got_opentempfd();
487 		if (packfd == -1) {
488 			err = got_error_from_errno("got_opentempfd");
489 			goto done;
490 		}
491 	} else {
492 		if (asprintf(&path, "%s/%s/fetching.pack",
493 		    repo_path, GOT_OBJECTS_PACK_DIR) == -1) {
494 			err = got_error_from_errno("asprintf");
495 			goto done;
496 		}
497 		err = got_opentemp_named_fd(&tmppackpath, &packfd, path);
498 		free(path);
499 		if (err)
500 			goto done;
501 		if (fchmod(packfd, GOT_DEFAULT_FILE_MODE) != 0) {
502 			err = got_error_from_errno2("fchmod", tmppackpath);
503 			goto done;
504 		}
505 	}
506 	if (list_refs_only) {
507 		idxfd = got_opentempfd();
508 		if (idxfd == -1) {
509 			err = got_error_from_errno("got_opentempfd");
510 			goto done;
511 		}
512 	} else {
513 		if (asprintf(&path, "%s/%s/fetching.idx",
514 		    repo_path, GOT_OBJECTS_PACK_DIR) == -1) {
515 			err = got_error_from_errno("asprintf");
516 			goto done;
517 		}
518 		err = got_opentemp_named_fd(&tmpidxpath, &idxfd, path);
519 		free(path);
520 		if (err)
521 			goto done;
522 		if (fchmod(idxfd, GOT_DEFAULT_FILE_MODE) != 0) {
523 			err = got_error_from_errno2("fchmod", tmpidxpath);
524 			goto done;
525 		}
526 	}
527 	nidxfd = dup(idxfd);
528 	if (nidxfd == -1) {
529 		err = got_error_from_errno("dup");
530 		goto done;
531 	}
532 
533 	for (i = 0; i < nitems(tmpfds); i++) {
534 		tmpfds[i] = got_opentempfd();
535 		if (tmpfds[i] == -1) {
536 			err = got_error_from_errno("got_opentempfd");
537 			goto done;
538 		}
539 	}
540 
541 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_fetchfds) == -1) {
542 		err = got_error_from_errno("socketpair");
543 		goto done;
544 	}
545 
546 	fetchpid = fork();
547 	if (fetchpid == -1) {
548 		err = got_error_from_errno("fork");
549 		goto done;
550 	} else if (fetchpid == 0){
551 		got_privsep_exec_child(imsg_fetchfds,
552 		    GOT_PATH_PROG_FETCH_PACK, tmppackpath);
553 	}
554 
555 	if (close(imsg_fetchfds[1]) != 0) {
556 		err = got_error_from_errno("close");
557 		goto done;
558 	}
559 	imsg_init(&fetchibuf, imsg_fetchfds[0]);
560 	nfetchfd = dup(fetchfd);
561 	if (nfetchfd == -1) {
562 		err = got_error_from_errno("dup");
563 		goto done;
564 	}
565 	err = got_privsep_send_fetch_req(&fetchibuf, nfetchfd, &have_refs,
566 	    fetch_all_branches, wanted_branches, wanted_refs,
567 	    list_refs_only, verbosity);
568 	if (err != NULL)
569 		goto done;
570 	nfetchfd = -1;
571 	npackfd = dup(packfd);
572 	if (npackfd == -1) {
573 		err = got_error_from_errno("dup");
574 		goto done;
575 	}
576 	err = got_privsep_send_fetch_outfd(&fetchibuf, npackfd);
577 	if (err != NULL)
578 		goto done;
579 	npackfd = -1;
580 
581 	packfile_size = 0;
582 	progress = calloc(GOT_FETCH_PKTMAX, 1);
583 	if (progress == NULL) {
584 		err = got_error_from_errno("calloc");
585 		goto done;
586 	}
587 
588 	*pack_hash = calloc(1, sizeof(**pack_hash));
589 	if (*pack_hash == NULL) {
590 		err = got_error_from_errno("calloc");
591 		goto done;
592 	}
593 
594 	while (!done) {
595 		struct got_object_id *id = NULL;
596 		char *refname = NULL;
597 		char *server_progress = NULL;
598 		off_t packfile_size_cur = 0;
599 
600 		err = got_privsep_recv_fetch_progress(&done,
601 		    &id, &refname, symrefs, &server_progress,
602 		    &packfile_size_cur, (*pack_hash)->sha1, &fetchibuf);
603 		if (err != NULL)
604 			goto done;
605 		if (!done && refname && id) {
606 			err = got_pathlist_insert(NULL, refs, refname, id);
607 			if (err)
608 				goto done;
609 		} else if (!done && server_progress) {
610 			char *p;
611 			/*
612 			 * XXX git-daemon tends to send batched output with
613 			 * lines spanning separate packets. Buffer progress
614 			 * output until we see a CR or LF to avoid giving
615 			 * partial lines of progress output to the callback.
616 			 */
617 			if (strlcat(progress, server_progress,
618 			    GOT_FETCH_PKTMAX) >= GOT_FETCH_PKTMAX) {
619 				progress[0] = '\0'; /* discard */
620 				continue;
621 			}
622 			while ((p = strchr(progress, '\r')) != NULL ||
623 			    (p = strchr(progress, '\n')) != NULL) {
624 				char *s;
625 				size_t n;
626 				char c = *p;
627 				*p = '\0';
628 				if (asprintf(&s, "%s%s", progress,
629 				    c == '\n' ? "\n" : "") == -1) {
630 					err = got_error_from_errno("asprintf");
631 					goto done;
632 				}
633 				err = progress_cb(progress_arg, s,
634 				    packfile_size_cur, 0, 0, 0, 0);
635 				free(s);
636 				if (err)
637 					break;
638 				n = strlen(progress);
639 				if (n < GOT_FETCH_PKTMAX - 1) {
640 					memmove(progress, &progress[n + 1],
641 					    GOT_FETCH_PKTMAX - n - 1);
642 				} else
643 					progress[0] = '\0';
644 			}
645 			free(server_progress);
646 			if (err)
647 				goto done;
648 		} else if (!done && packfile_size_cur != packfile_size) {
649 			err = progress_cb(progress_arg, NULL,
650 			    packfile_size_cur, 0, 0, 0, 0);
651 			if (err)
652 				break;
653 			packfile_size = packfile_size_cur;
654 		}
655 	}
656 	if (waitpid(fetchpid, &fetchstatus, 0) == -1) {
657 		err = got_error_from_errno("waitpid");
658 		goto done;
659 	}
660 
661 	if (lseek(packfd, 0, SEEK_SET) == -1) {
662 		err = got_error_from_errno("lseek");
663 		goto done;
664 	}
665 
666 	/* If zero data was fetched without error we are already up-to-date. */
667 	if (packfile_size == 0) {
668 		free(*pack_hash);
669 		*pack_hash = NULL;
670 		goto done;
671 	} else if (packfile_size < sizeof(pack_hdr) + SHA1_DIGEST_LENGTH) {
672 		err = got_error_msg(GOT_ERR_BAD_PACKFILE, "short pack file");
673 		goto done;
674 	} else {
675 		ssize_t n;
676 
677 		n = read(packfd, &pack_hdr, sizeof(pack_hdr));
678 		if (n == -1) {
679 			err = got_error_from_errno("read");
680 			goto done;
681 		}
682 		if (n != sizeof(pack_hdr)) {
683 			err = got_error(GOT_ERR_IO);
684 			goto done;
685 		}
686 		if (pack_hdr.signature != htobe32(GOT_PACKFILE_SIGNATURE)) {
687 			err = got_error_msg(GOT_ERR_BAD_PACKFILE,
688 			    "bad pack file signature");
689 			goto done;
690 		}
691 		if (pack_hdr.version != htobe32(GOT_PACKFILE_VERSION)) {
692 			err = got_error_msg(GOT_ERR_BAD_PACKFILE,
693 			    "bad pack file version");
694 			goto done;
695 		}
696 		nobj = be32toh(pack_hdr.nobjects);
697 		if (nobj == 0 &&
698 		    packfile_size > sizeof(pack_hdr) + SHA1_DIGEST_LENGTH)
699 			return got_error_msg(GOT_ERR_BAD_PACKFILE,
700 			    "bad pack file with zero objects");
701 		if (nobj != 0 &&
702 		    packfile_size <= sizeof(pack_hdr) + SHA1_DIGEST_LENGTH)
703 			return got_error_msg(GOT_ERR_BAD_PACKFILE,
704 			    "empty pack file with non-zero object count");
705 	}
706 
707 	/*
708 	 * If the pack file contains no objects, we may only need to update
709 	 * references in our repository. The caller will take care of that.
710 	 */
711 	if (nobj == 0)
712 		goto done;
713 
714 	if (lseek(packfd, 0, SEEK_SET) == -1) {
715 		err = got_error_from_errno("lseek");
716 		goto done;
717 	}
718  
719 	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, imsg_idxfds) == -1) {
720 		err = got_error_from_errno("socketpair");
721 		goto done;
722 	}
723 	idxpid = fork();
724 	if (idxpid == -1) {
725 		err= got_error_from_errno("fork");
726 		goto done;
727 	} else if (idxpid == 0)
728 		got_privsep_exec_child(imsg_idxfds,
729 		    GOT_PATH_PROG_INDEX_PACK, tmppackpath);
730 	if (close(imsg_idxfds[1]) != 0) {
731 		err = got_error_from_errno("close");
732 		goto done;
733 	}
734 	imsg_init(&idxibuf, imsg_idxfds[0]);
735 
736 	npackfd = dup(packfd);
737 	if (npackfd == -1) {
738 		err = got_error_from_errno("dup");
739 		goto done;
740 	}
741 	err = got_privsep_send_index_pack_req(&idxibuf, (*pack_hash)->sha1,
742 	    npackfd);
743 	if (err != NULL)
744 		goto done;
745 	npackfd = -1;
746 	err = got_privsep_send_index_pack_outfd(&idxibuf, nidxfd);
747 	if (err != NULL)
748 		goto done;
749 	nidxfd = -1;
750 	for (i = 0; i < nitems(tmpfds); i++) {
751 		err = got_privsep_send_tmpfd(&idxibuf, tmpfds[i]);
752 		if (err != NULL)
753 			goto done;
754 		tmpfds[i] = -1;
755 	}
756 	done = 0;
757 	while (!done) {
758 		int nobj_total, nobj_indexed, nobj_loose, nobj_resolved;
759 
760 		err = got_privsep_recv_index_progress(&done, &nobj_total,
761 		    &nobj_indexed, &nobj_loose, &nobj_resolved,
762 		    &idxibuf);
763 		if (err != NULL)
764 			goto done;
765 		if (nobj_indexed != 0) {
766 			err = progress_cb(progress_arg, NULL,
767 			    packfile_size, nobj_total,
768 			    nobj_indexed, nobj_loose, nobj_resolved);
769 			if (err)
770 				break;
771 		}
772 		imsg_clear(&idxibuf);
773 	}
774 	if (close(imsg_idxfds[0]) == -1) {
775 		err = got_error_from_errno("close");
776 		goto done;
777 	}
778 	if (waitpid(idxpid, &idxstatus, 0) == -1) {
779 		err = got_error_from_errno("waitpid");
780 		goto done;
781 	}
782 
783 	err = got_object_id_str(&id_str, *pack_hash);
784 	if (err)
785 		goto done;
786 	if (asprintf(&packpath, "%s/%s/pack-%s.pack",
787 	    repo_path, GOT_OBJECTS_PACK_DIR, id_str) == -1) {
788 		err = got_error_from_errno("asprintf");
789 		goto done;
790 	}
791 
792 	if (asprintf(&idxpath, "%s/%s/pack-%s.idx",
793 	    repo_path, GOT_OBJECTS_PACK_DIR, id_str) == -1) {
794 		err = got_error_from_errno("asprintf");
795 		goto done;
796 	}
797 
798 	if (rename(tmppackpath, packpath) == -1) {
799 		err = got_error_from_errno3("rename", tmppackpath, packpath);
800 		goto done;
801 	}
802 	free(tmppackpath);
803 	tmppackpath = NULL;
804 	if (rename(tmpidxpath, idxpath) == -1) {
805 		err = got_error_from_errno3("rename", tmpidxpath, idxpath);
806 		goto done;
807 	}
808 	free(tmpidxpath);
809 	tmpidxpath = NULL;
810 
811 done:
812 	if (tmppackpath && unlink(tmppackpath) == -1 && err == NULL)
813 		err = got_error_from_errno2("unlink", tmppackpath);
814 	if (tmpidxpath && unlink(tmpidxpath) == -1 && err == NULL)
815 		err = got_error_from_errno2("unlink", tmpidxpath);
816 	if (nfetchfd != -1 && close(nfetchfd) == -1 && err == NULL)
817 		err = got_error_from_errno("close");
818 	if (npackfd != -1 && close(npackfd) == -1 && err == NULL)
819 		err = got_error_from_errno("close");
820 	if (packfd != -1 && close(packfd) == -1 && err == NULL)
821 		err = got_error_from_errno("close");
822 	if (idxfd != -1 && close(idxfd) == -1 && err == NULL)
823 		err = got_error_from_errno("close");
824 	for (i = 0; i < nitems(tmpfds); i++) {
825 		if (tmpfds[i] != -1 && close(tmpfds[i]) == -1 && err == NULL)
826 			err = got_error_from_errno("close");
827 	}
828 	free(tmppackpath);
829 	free(tmpidxpath);
830 	free(idxpath);
831 	free(packpath);
832 	free(ref_prefix);
833 	free(progress);
834 
835 	TAILQ_FOREACH(pe, &have_refs, entry) {
836 		free((char *)pe->path);
837 		free(pe->data);
838 	}
839 	got_pathlist_free(&have_refs);
840 	got_ref_list_free(&my_refs);
841 	if (err) {
842 		free(*pack_hash);
843 		*pack_hash = NULL;
844 		TAILQ_FOREACH(pe, refs, entry) {
845 			free((void *)pe->path);
846 			free(pe->data);
847 		}
848 		got_pathlist_free(refs);
849 		TAILQ_FOREACH(pe, symrefs, entry) {
850 			free((void *)pe->path);
851 			free(pe->data);
852 		}
853 		got_pathlist_free(symrefs);
854 	}
855 	return err;
856 }