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Date:: Tue Apr 4 21:15:49 2023 UTC
Message:: add support for protecting references against 'got send -f' to gotd ok op@
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1 /*
2  * Copyright (c) 2018, 2019, 2020 Stefan Sperling <stsp@openbsd.org>
3  *
4  * Permission to use, copy, modify, and distribute this software for any
5  * purpose with or without fee is hereby granted, provided that the above
6  * copyright notice and this permission notice appear in all copies.
7  *
8  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
15  */
16 
17 #include "got_compat.h"
18 
19 #include <sys/types.h>
20 #include <sys/stat.h>
21 #include <sys/queue.h>
22 #include <sys/uio.h>
23 #include <sys/socket.h>
24 #include <sys/wait.h>
25 #include <sys/mman.h>
26 
27 #include <errno.h>
28 #include <stdio.h>
29 #include <stdlib.h>
30 #include <string.h>
31 #include <stdint.h>
32 #include <zlib.h>
33 #include <ctype.h>
34 #include <limits.h>
35 #include <time.h>
36 #include <unistd.h>
37 
38 #include "got_error.h"
39 #include "got_object.h"
40 #include "got_repository.h"
41 #include "got_opentemp.h"
42 #include "got_path.h"
43 
44 #include "got_lib_hash.h"
45 #include "got_lib_delta.h"
46 #include "got_lib_inflate.h"
47 #include "got_lib_object.h"
48 #include "got_lib_object_parse.h"
49 #include "got_lib_object_cache.h"
50 #include "got_lib_pack.h"
51 #include "got_lib_repository.h"
52 
53 #ifndef nitems
54 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
55 #endif
56 
57 struct got_object_id *
58 got_object_id_dup(struct got_object_id *id1)
59 {
60 	struct got_object_id *id2;
61 
62 	id2 = malloc(sizeof(*id2));
63 	if (id2 == NULL)
64 		return NULL;
65 	memcpy(id2, id1, sizeof(*id2));
66 	return id2;
67 }
68 
69 int
70 got_object_id_cmp(const struct got_object_id *id1,
71     const struct got_object_id *id2)
72 {
73 	return memcmp(id1->sha1, id2->sha1, SHA1_DIGEST_LENGTH);
74 }
75 
76 const struct got_error *
77 got_object_qid_alloc_partial(struct got_object_qid **qid)
78 {
79 	*qid = malloc(sizeof(**qid));
80 	if (*qid == NULL)
81 		return got_error_from_errno("malloc");
82 
83 	(*qid)->data = NULL;
84 	return NULL;
85 }
86 
87 const struct got_error *
88 got_object_id_str(char **outbuf, struct got_object_id *id)
89 {
90 	static const size_t len = GOT_OBJECT_ID_HEX_MAXLEN;
91 
92 	*outbuf = malloc(len);
93 	if (*outbuf == NULL)
94 		return got_error_from_errno("malloc");
95 
96 	if (got_object_id_hex(id, *outbuf, len) == NULL) {
97 		free(*outbuf);
98 		*outbuf = NULL;
99 		return got_error(GOT_ERR_BAD_OBJ_ID_STR);
100 	}
101 
102 	return NULL;
103 }
104 
105 char *
106 got_object_id_hex(struct got_object_id *id, char *buf, size_t len)
107 {
108 	return got_sha1_digest_to_str(id->sha1, buf, len);
109 }
110 
111 const struct got_error *
112 got_object_type_label(const char **label, int obj_type)
113 {
114 	const struct got_error *err = NULL;
115 
116 	switch (obj_type) {
117 	case GOT_OBJ_TYPE_BLOB:
118 		*label = GOT_OBJ_LABEL_BLOB;
119 		break;
120 	case GOT_OBJ_TYPE_TREE:
121 		*label = GOT_OBJ_LABEL_TREE;
122 		break;
123 	case GOT_OBJ_TYPE_COMMIT:
124 		*label = GOT_OBJ_LABEL_COMMIT;
125 		break;
126 	case GOT_OBJ_TYPE_TAG:
127 		*label = GOT_OBJ_LABEL_TAG;
128 		break;
129 	default:
130 		*label = NULL;
131 		err = got_error(GOT_ERR_OBJ_TYPE);
132 		break;
133 	}
134 
135 	return err;
136 }
137 
138 void
139 got_object_close(struct got_object *obj)
140 {
141 	if (obj->refcnt > 0) {
142 		obj->refcnt--;
143 		if (obj->refcnt > 0)
144 			return;
145 	}
146 
147 	if (obj->flags & GOT_OBJ_FLAG_DELTIFIED) {
148 		struct got_delta *delta;
149 		while (!STAILQ_EMPTY(&obj->deltas.entries)) {
150 			delta = STAILQ_FIRST(&obj->deltas.entries);
151 			STAILQ_REMOVE_HEAD(&obj->deltas.entries, entry);
152 			free(delta);
153 		}
154 	}
155 	free(obj);
156 }
157 
158 const struct got_error *
159 got_object_raw_close(struct got_raw_object *obj)
160 {
161 	const struct got_error *err = NULL;
162 
163 	if (obj->refcnt > 0) {
164 		obj->refcnt--;
165 		if (obj->refcnt > 0)
166 			return NULL;
167 	}
168 
169 	if (obj->close_cb)
170 		obj->close_cb(obj);
171 
172 	if (obj->f == NULL) {
173 		if (obj->fd != -1) {
174 			if (munmap(obj->data, obj->hdrlen + obj->size) == -1)
175 				err = got_error_from_errno("munmap");
176 			if (close(obj->fd) == -1 && err == NULL)
177 				err = got_error_from_errno("close");
178 		} else
179 			free(obj->data);
180 	} else {
181 		if (fclose(obj->f) == EOF && err == NULL)
182 			err = got_error_from_errno("fclose");
183 	}
184 	free(obj);
185 	return err;
186 }
187 
188 void
189 got_object_qid_free(struct got_object_qid *qid)
190 {
191 	free(qid);
192 }
193 
194 void
195 got_object_id_queue_free(struct got_object_id_queue *ids)
196 {
197 	struct got_object_qid *qid;
198 
199 	while (!STAILQ_EMPTY(ids)) {
200 		qid = STAILQ_FIRST(ids);
201 		STAILQ_REMOVE_HEAD(ids, entry);
202 		got_object_qid_free(qid);
203 	}
204 }
205 
206 const struct got_error *
207 got_object_parse_header(struct got_object **obj, char *buf, size_t len)
208 {
209 	const char *obj_labels[] = {
210 		GOT_OBJ_LABEL_COMMIT,
211 		GOT_OBJ_LABEL_TREE,
212 		GOT_OBJ_LABEL_BLOB,
213 		GOT_OBJ_LABEL_TAG,
214 	};
215 	const int obj_types[] = {
216 		GOT_OBJ_TYPE_COMMIT,
217 		GOT_OBJ_TYPE_TREE,
218 		GOT_OBJ_TYPE_BLOB,
219 		GOT_OBJ_TYPE_TAG,
220 	};
221 	int type = 0;
222 	size_t size = 0;
223 	size_t i;
224 	char *end;
225 
226 	*obj = NULL;
227 
228 	end = memchr(buf, '\0', len);
229 	if (end == NULL)
230 		return got_error(GOT_ERR_BAD_OBJ_HDR);
231 
232 	for (i = 0; i < nitems(obj_labels); i++) {
233 		const char *label = obj_labels[i];
234 		size_t label_len = strlen(label);
235 		const char *errstr;
236 
237 		if (len <= label_len || buf + label_len >= end ||
238 		    strncmp(buf, label, label_len) != 0)
239 			continue;
240 
241 		type = obj_types[i];
242 		size = strtonum(buf + label_len, 0, LONG_MAX, &errstr);
243 		if (errstr != NULL)
244 			return got_error(GOT_ERR_BAD_OBJ_HDR);
245 		break;
246 	}
247 
248 	if (type == 0)
249 		return got_error(GOT_ERR_BAD_OBJ_HDR);
250 
251 	*obj = calloc(1, sizeof(**obj));
252 	if (*obj == NULL)
253 		return got_error_from_errno("calloc");
254 	(*obj)->type = type;
255 	(*obj)->hdrlen = end - buf + 1;
256 	(*obj)->size = size;
257 	return NULL;
258 }
259 
260 const struct got_error *
261 got_object_read_header(struct got_object **obj, int fd)
262 {
263 	const struct got_error *err;
264 	struct got_inflate_buf zb;
265 	uint8_t *buf;
266 	const size_t zbsize = 64;
267 	size_t outlen, totlen;
268 	int nbuf = 1;
269 
270 	*obj = NULL;
271 
272 	buf = malloc(zbsize);
273 	if (buf == NULL)
274 		return got_error_from_errno("malloc");
275 	buf[0] = '\0';
276 
277 	err = got_inflate_init(&zb, buf, zbsize, NULL);
278 	if (err)
279 		return err;
280 
281 	totlen = 0;
282 	do {
283 		err = got_inflate_read_fd(&zb, fd, &outlen, NULL);
284 		if (err)
285 			goto done;
286 		if (outlen == 0)
287 			break;
288 		totlen += outlen;
289 		if (memchr(zb.outbuf, '\0', outlen) == NULL) {
290 			uint8_t *newbuf;
291 			nbuf++;
292 			newbuf = recallocarray(buf, nbuf - 1, nbuf, zbsize);
293 			if (newbuf == NULL) {
294 				err = got_error_from_errno("recallocarray");
295 				goto done;
296 			}
297 			buf = newbuf;
298 			zb.outbuf = newbuf + totlen;
299 			zb.outlen = (nbuf * zbsize) - totlen;
300 		}
301 	} while (memchr(zb.outbuf, '\0', outlen) == NULL);
302 
303 	err = got_object_parse_header(obj, buf, totlen);
304 done:
305 	free(buf);
306 	got_inflate_end(&zb);
307 	return err;
308 }
309 
310 const struct got_error *
311 got_object_read_raw(uint8_t **outbuf, off_t *size, size_t *hdrlen,
312     size_t max_in_mem_size, int outfd, struct got_object_id *expected_id,
313     int infd)
314 {
315 	const struct got_error *err = NULL;
316 	struct got_object *obj;
317 	struct got_inflate_checksum csum;
318 	struct got_object_id id;
319 	struct got_hash ctx;
320 	size_t len, consumed;
321 	FILE *f = NULL;
322 
323 	*outbuf = NULL;
324 	*size = 0;
325 	*hdrlen = 0;
326 
327 	got_hash_init(&ctx, GOT_HASH_SHA1);
328 	memset(&csum, 0, sizeof(csum));
329 	csum.output_ctx = &ctx;
330 
331 	if (lseek(infd, SEEK_SET, 0) == -1)
332 		return got_error_from_errno("lseek");
333 
334 	err = got_object_read_header(&obj, infd);
335 	if (err)
336 		return err;
337 
338 	if (lseek(infd, SEEK_SET, 0) == -1)
339 		return got_error_from_errno("lseek");
340 
341 	if (obj->size + obj->hdrlen <= max_in_mem_size) {
342 		err = got_inflate_to_mem_fd(outbuf, &len, &consumed, &csum,
343 		    obj->size + obj->hdrlen, infd);
344 	} else {
345 		int fd;
346 		/*
347 		 * XXX This uses an extra file descriptor for no good reason.
348 		 * We should have got_inflate_fd_to_fd().
349 		 */
350 		fd = dup(infd);
351 		if (fd == -1)
352 			return got_error_from_errno("dup");
353 		f = fdopen(fd, "r");
354 		if (f == NULL) {
355 			err = got_error_from_errno("fdopen");
356 			abort();
357 			close(fd);
358 			goto done;
359 		}
360 		err = got_inflate_to_fd(&len, f, &csum, outfd);
361 	}
362 	if (err)
363 		goto done;
364 
365 	if (len < obj->hdrlen || len != obj->hdrlen + obj->size) {
366 		err = got_error(GOT_ERR_BAD_OBJ_HDR);
367 		goto done;
368 	}
369 
370 	got_hash_final_object_id(&ctx, &id);
371 	if (got_object_id_cmp(expected_id, &id) != 0) {
372 		err = got_error_checksum(expected_id);
373 		goto done;
374 	}
375 
376 	*size = obj->size;
377 	*hdrlen = obj->hdrlen;
378 done:
379 	got_object_close(obj);
380 	if (f && fclose(f) == EOF && err == NULL)
381 		err = got_error_from_errno("fclose");
382 	return err;
383 }
384 
385 struct got_commit_object *
386 got_object_commit_alloc_partial(void)
387 {
388 	struct got_commit_object *commit;
389 
390 	commit = calloc(1, sizeof(*commit));
391 	if (commit == NULL)
392 		return NULL;
393 	commit->tree_id = malloc(sizeof(*commit->tree_id));
394 	if (commit->tree_id == NULL) {
395 		free(commit);
396 		return NULL;
397 	}
398 
399 	STAILQ_INIT(&commit->parent_ids);
400 
401 	return commit;
402 }
403 
404 const struct got_error *
405 got_object_commit_add_parent(struct got_commit_object *commit,
406     const char *id_str)
407 {
408 	const struct got_error *err = NULL;
409 	struct got_object_qid *qid;
410 
411 	err = got_object_qid_alloc_partial(&qid);
412 	if (err)
413 		return err;
414 
415 	if (!got_parse_object_id(&qid->id, id_str, GOT_HASH_SHA1)) {
416 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
417 		got_object_qid_free(qid);
418 		return err;
419 	}
420 
421 	STAILQ_INSERT_TAIL(&commit->parent_ids, qid, entry);
422 	commit->nparents++;
423 
424 	return NULL;
425 }
426 
427 static const struct got_error *
428 parse_gmtoff(time_t *gmtoff, const char *tzstr)
429 {
430 	int sign = 1;
431 	const char *p = tzstr;
432 	time_t h, m;
433 
434 	*gmtoff = 0;
435 
436 	if (*p == '-')
437 		sign = -1;
438 	else if (*p != '+')
439 		return got_error(GOT_ERR_BAD_OBJ_DATA);
440 	p++;
441 	if (!isdigit((unsigned char)*p) &&
442 	    !isdigit((unsigned char)*(p + 1)))
443 		return got_error(GOT_ERR_BAD_OBJ_DATA);
444 	h = (((*p - '0') * 10) + (*(p + 1) - '0'));
445 
446 	p += 2;
447 	if (!isdigit((unsigned char)*p) &&
448 	    !isdigit((unsigned char)*(p + 1)))
449 		return got_error(GOT_ERR_BAD_OBJ_DATA);
450 	m = ((*p - '0') * 10) + (*(p + 1) - '0');
451 
452 	*gmtoff = (h * 60 * 60 + m * 60) * sign;
453 	return NULL;
454 }
455 
456 static const struct got_error *
457 parse_commit_time(time_t *time, time_t *gmtoff, char *committer)
458 {
459 	const struct got_error *err = NULL;
460 	const char *errstr;
461 	char *space, *tzstr;
462 
463 	/* Parse and strip off trailing timezone indicator string. */
464 	space = strrchr(committer, ' ');
465 	if (space == NULL)
466 		return got_error(GOT_ERR_BAD_OBJ_DATA);
467 	tzstr = strdup(space + 1);
468 	if (tzstr == NULL)
469 		return got_error_from_errno("strdup");
470 	err = parse_gmtoff(gmtoff, tzstr);
471 	free(tzstr);
472 	if (err) {
473 		if (err->code != GOT_ERR_BAD_OBJ_DATA)
474 			return err;
475 		/* Old versions of Git omitted the timestamp. */
476 		*time = 0;
477 		*gmtoff = 0;
478 		return NULL;
479 	}
480 	*space = '\0';
481 
482 	/* Timestamp is separated from committer name + email by space. */
483 	space = strrchr(committer, ' ');
484 	if (space == NULL)
485 		return got_error(GOT_ERR_BAD_OBJ_DATA);
486 
487 	/* Timestamp parsed here is expressed as UNIX timestamp (UTC). */
488 	*time = strtonum(space + 1, 0, INT64_MAX, &errstr);
489 	if (errstr)
490 		return got_error(GOT_ERR_BAD_OBJ_DATA);
491 
492 	/* Strip off parsed time information, leaving just author and email. */
493 	*space = '\0';
494 
495 	return NULL;
496 }
497 
498 void
499 got_object_commit_close(struct got_commit_object *commit)
500 {
501 	if (commit->refcnt > 0) {
502 		commit->refcnt--;
503 		if (commit->refcnt > 0)
504 			return;
505 	}
506 
507 	got_object_id_queue_free(&commit->parent_ids);
508 	free(commit->tree_id);
509 	free(commit->author);
510 	free(commit->committer);
511 	free(commit->logmsg);
512 	free(commit);
513 }
514 
515 struct got_object_id *
516 got_object_commit_get_tree_id(struct got_commit_object *commit)
517 {
518 	return commit->tree_id;
519 }
520 
521 int
522 got_object_commit_get_nparents(struct got_commit_object *commit)
523 {
524 	return commit->nparents;
525 }
526 
527 const struct got_object_id_queue *
528 got_object_commit_get_parent_ids(struct got_commit_object *commit)
529 {
530 	return &commit->parent_ids;
531 }
532 
533 const char *
534 got_object_commit_get_author(struct got_commit_object *commit)
535 {
536 	return commit->author;
537 }
538 
539 time_t
540 got_object_commit_get_author_time(struct got_commit_object *commit)
541 {
542 	return commit->author_time;
543 }
544 
545 time_t got_object_commit_get_author_gmtoff(struct got_commit_object *commit)
546 {
547 	return commit->author_gmtoff;
548 }
549 
550 const char *
551 got_object_commit_get_committer(struct got_commit_object *commit)
552 {
553 	return commit->committer;
554 }
555 
556 time_t
557 got_object_commit_get_committer_time(struct got_commit_object *commit)
558 {
559 	return commit->committer_time;
560 }
561 
562 time_t
563 got_object_commit_get_committer_gmtoff(struct got_commit_object *commit)
564 {
565 	return commit->committer_gmtoff;
566 }
567 
568 const struct got_error *
569 got_object_commit_get_logmsg(char **logmsg, struct got_commit_object *commit)
570 {
571 	const struct got_error *err = NULL;
572 	const char *src;
573 	char *dst;
574 	size_t len;
575 
576 	len = strlen(commit->logmsg);
577 	*logmsg = malloc(len + 2); /* leave room for a trailing \n and \0 */
578 	if (*logmsg == NULL)
579 		return got_error_from_errno("malloc");
580 
581 	/*
582 	 * Strip out unusual headers. Headers are separated from the commit
583 	 * message body by a single empty line.
584 	 */
585 	src = commit->logmsg;
586 	dst = *logmsg;
587 	while (*src != '\0' && *src != '\n') {
588 		int copy_header = 1, eol = 0;
589 		if (strncmp(src, GOT_COMMIT_LABEL_TREE,
590 		    strlen(GOT_COMMIT_LABEL_TREE)) != 0 &&
591 		    strncmp(src, GOT_COMMIT_LABEL_AUTHOR,
592 		    strlen(GOT_COMMIT_LABEL_AUTHOR)) != 0 &&
593 		    strncmp(src, GOT_COMMIT_LABEL_PARENT,
594 		    strlen(GOT_COMMIT_LABEL_PARENT)) != 0 &&
595 		    strncmp(src, GOT_COMMIT_LABEL_COMMITTER,
596 		    strlen(GOT_COMMIT_LABEL_COMMITTER)) != 0)
597 			copy_header = 0;
598 
599 		while (*src != '\0' && !eol) {
600 			if (copy_header) {
601 				*dst = *src;
602 				dst++;
603 			}
604 			if (*src == '\n')
605 				eol = 1;
606 			src++;
607 		}
608 	}
609 	*dst = '\0';
610 
611 	if (strlcat(*logmsg, src, len + 1) >= len + 1) {
612 		err = got_error(GOT_ERR_NO_SPACE);
613 		goto done;
614 	}
615 
616 	/* Trim redundant trailing whitespace. */
617 	len = strlen(*logmsg);
618 	while (len > 1 && isspace((unsigned char)(*logmsg)[len - 2]) &&
619 	    isspace((unsigned char)(*logmsg)[len - 1])) {
620 		(*logmsg)[len - 1] = '\0';
621 		len--;
622 	}
623 
624 	/* Append a trailing newline if missing. */
625 	if (len > 0 && (*logmsg)[len - 1] != '\n') {
626 		(*logmsg)[len] = '\n';
627 		(*logmsg)[len + 1] = '\0';
628 	}
629 done:
630 	if (err) {
631 		free(*logmsg);
632 		*logmsg = NULL;
633 	}
634 	return err;
635 }
636 
637 const char *
638 got_object_commit_get_logmsg_raw(struct got_commit_object *commit)
639 {
640 	return commit->logmsg;
641 }
642 
643 const struct got_error *
644 got_object_parse_commit(struct got_commit_object **commit, char *buf,
645     size_t len)
646 {
647 	const struct got_error *err = NULL;
648 	enum got_hash_algorithm algo = GOT_HASH_SHA1;
649 	char *s = buf;
650 	size_t label_len;
651 	ssize_t remain = (ssize_t)len;
652 
653 	if (remain == 0)
654 		return got_error(GOT_ERR_BAD_OBJ_DATA);
655 
656 	*commit = got_object_commit_alloc_partial();
657 	if (*commit == NULL)
658 		return got_error_from_errno("got_object_commit_alloc_partial");
659 
660 	label_len = strlen(GOT_COMMIT_LABEL_TREE);
661 	if (strncmp(s, GOT_COMMIT_LABEL_TREE, label_len) == 0) {
662 		remain -= label_len;
663 		if (remain < SHA1_DIGEST_STRING_LENGTH) {
664 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
665 			goto done;
666 		}
667 		s += label_len;
668 		if (!got_parse_object_id((*commit)->tree_id, s, algo)) {
669 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
670 			goto done;
671 		}
672 		remain -= SHA1_DIGEST_STRING_LENGTH;
673 		s += SHA1_DIGEST_STRING_LENGTH;
674 	} else {
675 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
676 		goto done;
677 	}
678 
679 	label_len = strlen(GOT_COMMIT_LABEL_PARENT);
680 	while (strncmp(s, GOT_COMMIT_LABEL_PARENT, label_len) == 0) {
681 		remain -= label_len;
682 		if (remain < SHA1_DIGEST_STRING_LENGTH) {
683 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
684 			goto done;
685 		}
686 		s += label_len;
687 		err = got_object_commit_add_parent(*commit, s);
688 		if (err)
689 			goto done;
690 
691 		remain -= SHA1_DIGEST_STRING_LENGTH;
692 		s += SHA1_DIGEST_STRING_LENGTH;
693 	}
694 
695 	label_len = strlen(GOT_COMMIT_LABEL_AUTHOR);
696 	if (strncmp(s, GOT_COMMIT_LABEL_AUTHOR, label_len) == 0) {
697 		char *p;
698 		size_t slen;
699 
700 		remain -= label_len;
701 		if (remain <= 0) {
702 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
703 			goto done;
704 		}
705 		s += label_len;
706 		p = memchr(s, '\n', remain);
707 		if (p == NULL) {
708 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
709 			goto done;
710 		}
711 		*p = '\0';
712 		slen = strlen(s);
713 		err = parse_commit_time(&(*commit)->author_time,
714 		    &(*commit)->author_gmtoff, s);
715 		if (err)
716 			goto done;
717 		(*commit)->author = strdup(s);
718 		if ((*commit)->author == NULL) {
719 			err = got_error_from_errno("strdup");
720 			goto done;
721 		}
722 		s += slen + 1;
723 		remain -= slen + 1;
724 	}
725 
726 	label_len = strlen(GOT_COMMIT_LABEL_COMMITTER);
727 	if (strncmp(s, GOT_COMMIT_LABEL_COMMITTER, label_len) == 0) {
728 		char *p;
729 		size_t slen;
730 
731 		remain -= label_len;
732 		if (remain <= 0) {
733 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
734 			goto done;
735 		}
736 		s += label_len;
737 		p = memchr(s, '\n', remain);
738 		if (p == NULL) {
739 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
740 			goto done;
741 		}
742 		*p = '\0';
743 		slen = strlen(s);
744 		err = parse_commit_time(&(*commit)->committer_time,
745 		    &(*commit)->committer_gmtoff, s);
746 		if (err)
747 			goto done;
748 		(*commit)->committer = strdup(s);
749 		if ((*commit)->committer == NULL) {
750 			err = got_error_from_errno("strdup");
751 			goto done;
752 		}
753 		s += slen + 1;
754 		remain -= slen + 1;
755 	}
756 
757 	(*commit)->logmsg = strndup(s, remain);
758 	if ((*commit)->logmsg == NULL) {
759 		err = got_error_from_errno("strndup");
760 		goto done;
761 	}
762 done:
763 	if (err) {
764 		got_object_commit_close(*commit);
765 		*commit = NULL;
766 	}
767 	return err;
768 }
769 
770 const struct got_error *
771 got_object_read_commit(struct got_commit_object **commit, int fd,
772     struct got_object_id *expected_id, size_t expected_size)
773 {
774 	struct got_object *obj = NULL;
775 	const struct got_error *err = NULL;
776 	size_t len;
777 	uint8_t *p;
778 	struct got_inflate_checksum csum;
779 	struct got_hash ctx;
780 	struct got_object_id id;
781 
782 	got_hash_init(&ctx, GOT_HASH_SHA1);
783 	memset(&csum, 0, sizeof(csum));
784 	csum.output_ctx = &ctx;
785 
786 	err = got_inflate_to_mem_fd(&p, &len, NULL, &csum, expected_size, fd);
787 	if (err)
788 		return err;
789 
790 	got_hash_final_object_id(&ctx, &id);
791 	if (got_object_id_cmp(expected_id, &id) != 0) {
792 		err = got_error_checksum(expected_id);
793 		goto done;
794 	}
795 
796 	err = got_object_parse_header(&obj, p, len);
797 	if (err)
798 		goto done;
799 
800 	if (len < obj->hdrlen + obj->size) {
801 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
802 		goto done;
803 	}
804 
805 	if (obj->type != GOT_OBJ_TYPE_COMMIT) {
806 		err = got_error(GOT_ERR_OBJ_TYPE);
807 		goto done;
808 	}
809 
810 	/* Skip object header. */
811 	len -= obj->hdrlen;
812 	err = got_object_parse_commit(commit, p + obj->hdrlen, len);
813 done:
814 	free(p);
815 	if (obj)
816 		got_object_close(obj);
817 	return err;
818 }
819 
820 void
821 got_object_tree_close(struct got_tree_object *tree)
822 {
823 	if (tree->refcnt > 0) {
824 		tree->refcnt--;
825 		if (tree->refcnt > 0)
826 			return;
827 	}
828 
829 	free(tree->entries);
830 	free(tree);
831 }
832 
833 static const struct got_error *
834 parse_tree_entry(struct got_parsed_tree_entry *pte, size_t *elen, char *buf,
835     size_t maxlen)
836 {
837 	char *p, *space;
838 
839 	*elen = 0;
840 
841 	*elen = strnlen(buf, maxlen) + 1;
842 	if (*elen > maxlen)
843 		return got_error(GOT_ERR_BAD_OBJ_DATA);
844 
845 	space = memchr(buf, ' ', *elen);
846 	if (space == NULL || space <= buf)
847 		return got_error(GOT_ERR_BAD_OBJ_DATA);
848 
849 	pte->mode = 0;
850 	p = buf;
851 	while (p < space) {
852 		if (*p < '0' || *p > '7')
853 			return got_error(GOT_ERR_BAD_OBJ_DATA);
854 		pte->mode <<= 3;
855 		pte->mode |= *p - '0';
856 		p++;
857 	}
858 
859 	if (*elen > maxlen || maxlen - *elen < SHA1_DIGEST_LENGTH)
860 		return got_error(GOT_ERR_BAD_OBJ_DATA);
861 
862 	pte->name = space + 1;
863 	pte->namelen = strlen(pte->name);
864 	buf += *elen;
865 	pte->id = buf;
866 	*elen += SHA1_DIGEST_LENGTH;
867 	return NULL;
868 }
869 
870 static int
871 pte_cmp(const void *pa, const void *pb)
872 {
873 	const struct got_parsed_tree_entry *a = pa, *b = pb;
874 
875 	return got_path_cmp(a->name, b->name, a->namelen, b->namelen);
876 }
877 
878 const struct got_error *
879 got_object_parse_tree(struct got_parsed_tree_entry **entries, size_t *nentries,
880     size_t *nentries_alloc, uint8_t *buf, size_t len)
881 {
882 	const struct got_error *err = NULL;
883 	size_t remain = len;
884 	const size_t nalloc = 16;
885 	struct got_parsed_tree_entry *pte;
886 	int i;
887 
888 	*nentries = 0;
889 	if (remain == 0)
890 		return NULL; /* tree is empty */
891 
892 	while (remain > 0) {
893 		size_t elen;
894 
895 		if (*nentries >= *nentries_alloc) {
896 			pte = recallocarray(*entries, *nentries_alloc,
897 			    *nentries_alloc + nalloc, sizeof(**entries));
898 			if (pte == NULL) {
899 				err = got_error_from_errno("recallocarray");
900 				goto done;
901 			}
902 			*entries = pte;
903 			*nentries_alloc += nalloc;
904 		}
905 
906 		pte = &(*entries)[*nentries];
907 		err = parse_tree_entry(pte, &elen, buf, remain);
908 		if (err)
909 			goto done;
910 		buf += elen;
911 		remain -= elen;
912 		(*nentries)++;
913 	}
914 
915 	if (remain != 0) {
916 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
917 		goto done;
918 	}
919 
920 	if (*nentries > 1) {
921 		mergesort(*entries, *nentries, sizeof(**entries), pte_cmp);
922 
923 		for (i = 0; i < *nentries - 1; i++) {
924 			struct got_parsed_tree_entry *prev = &(*entries)[i];
925 			pte = &(*entries)[i + 1];
926 			if (got_path_cmp(prev->name, pte->name,
927 			    prev->namelen, pte->namelen) == 0) {
928 				err = got_error(GOT_ERR_TREE_DUP_ENTRY);
929 				break;
930 			}
931 		}
932 	}
933 done:
934 	if (err)
935 		*nentries = 0;
936 	return err;
937 }
938 
939 const struct got_error *
940 got_object_read_tree(struct got_parsed_tree_entry **entries, size_t *nentries,
941     size_t *nentries_alloc, uint8_t **p, int fd,
942     struct got_object_id *expected_id)
943 {
944 	const struct got_error *err = NULL;
945 	struct got_object *obj = NULL;
946 	size_t len;
947 	struct got_inflate_checksum csum;
948 	struct got_hash ctx;
949 	struct got_object_id id;
950 
951 	got_hash_init(&ctx, GOT_HASH_SHA1);
952 	memset(&csum, 0, sizeof(csum));
953 	csum.output_ctx = &ctx;
954 
955 	err = got_inflate_to_mem_fd(p, &len, NULL, &csum, 0, fd);
956 	if (err)
957 		return err;
958 
959 	got_hash_final_object_id(&ctx, &id);
960 	if (got_object_id_cmp(expected_id, &id) != 0) {
961 		err = got_error_checksum(expected_id);
962 		goto done;
963 	}
964 
965 	err = got_object_parse_header(&obj, *p, len);
966 	if (err)
967 		goto done;
968 
969 	if (len < obj->hdrlen + obj->size) {
970 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
971 		goto done;
972 	}
973 
974 	/* Skip object header. */
975 	len -= obj->hdrlen;
976 	err = got_object_parse_tree(entries, nentries, nentries_alloc,
977 	    *p + obj->hdrlen, len);
978 done:
979 	if (obj)
980 		got_object_close(obj);
981 	return err;
982 }
983 
984 void
985 got_object_tag_close(struct got_tag_object *tag)
986 {
987 	if (tag->refcnt > 0) {
988 		tag->refcnt--;
989 		if (tag->refcnt > 0)
990 			return;
991 	}
992 
993 	free(tag->tag);
994 	free(tag->tagger);
995 	free(tag->tagmsg);
996 	free(tag);
997 }
998 
999 const struct got_error *
1000 got_object_parse_tag(struct got_tag_object **tag, uint8_t *buf, size_t len)
1001 {
1002 	const struct got_error *err = NULL;
1003 	enum got_hash_algorithm algo = GOT_HASH_SHA1;
1004 	size_t remain = len;
1005 	char *s = buf;
1006 	size_t label_len;
1007 
1008 	if (remain == 0)
1009 		return got_error(GOT_ERR_BAD_OBJ_DATA);
1010 
1011 	*tag = calloc(1, sizeof(**tag));
1012 	if (*tag == NULL)
1013 		return got_error_from_errno("calloc");
1014 
1015 	label_len = strlen(GOT_TAG_LABEL_OBJECT);
1016 	if (strncmp(s, GOT_TAG_LABEL_OBJECT, label_len) == 0) {
1017 		remain -= label_len;
1018 		if (remain < SHA1_DIGEST_STRING_LENGTH) {
1019 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1020 			goto done;
1021 		}
1022 		s += label_len;
1023 		if (!got_parse_object_id(&(*tag)->id, s, algo)) {
1024 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1025 			goto done;
1026 		}
1027 		remain -= SHA1_DIGEST_STRING_LENGTH;
1028 		s += SHA1_DIGEST_STRING_LENGTH;
1029 	} else {
1030 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
1031 		goto done;
1032 	}
1033 
1034 	if (remain <= 0) {
1035 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
1036 		goto done;
1037 	}
1038 
1039 	label_len = strlen(GOT_TAG_LABEL_TYPE);
1040 	if (strncmp(s, GOT_TAG_LABEL_TYPE, label_len) == 0) {
1041 		remain -= label_len;
1042 		if (remain <= 0) {
1043 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1044 			goto done;
1045 		}
1046 		s += label_len;
1047 		if (strncmp(s, GOT_OBJ_LABEL_COMMIT,
1048 		    strlen(GOT_OBJ_LABEL_COMMIT)) == 0) {
1049 			(*tag)->obj_type = GOT_OBJ_TYPE_COMMIT;
1050 			label_len = strlen(GOT_OBJ_LABEL_COMMIT);
1051 			s += label_len;
1052 			remain -= label_len;
1053 		} else if (strncmp(s, GOT_OBJ_LABEL_TREE,
1054 		    strlen(GOT_OBJ_LABEL_TREE)) == 0) {
1055 			(*tag)->obj_type = GOT_OBJ_TYPE_TREE;
1056 			label_len = strlen(GOT_OBJ_LABEL_TREE);
1057 			s += label_len;
1058 			remain -= label_len;
1059 		} else if (strncmp(s, GOT_OBJ_LABEL_BLOB,
1060 		    strlen(GOT_OBJ_LABEL_BLOB)) == 0) {
1061 			(*tag)->obj_type = GOT_OBJ_TYPE_BLOB;
1062 			label_len = strlen(GOT_OBJ_LABEL_BLOB);
1063 			s += label_len;
1064 			remain -= label_len;
1065 		} else if (strncmp(s, GOT_OBJ_LABEL_TAG,
1066 		    strlen(GOT_OBJ_LABEL_TAG)) == 0) {
1067 			(*tag)->obj_type = GOT_OBJ_TYPE_TAG;
1068 			label_len = strlen(GOT_OBJ_LABEL_TAG);
1069 			s += label_len;
1070 			remain -= label_len;
1071 		} else {
1072 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1073 			goto done;
1074 		}
1075 
1076 		if (remain <= 0 || *s != '\n') {
1077 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1078 			goto done;
1079 		}
1080 		s++;
1081 		remain--;
1082 		if (remain <= 0) {
1083 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1084 			goto done;
1085 		}
1086 	} else {
1087 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
1088 		goto done;
1089 	}
1090 
1091 	label_len = strlen(GOT_TAG_LABEL_TAG);
1092 	if (strncmp(s, GOT_TAG_LABEL_TAG, label_len) == 0) {
1093 		char *p;
1094 		size_t slen;
1095 		remain -= label_len;
1096 		if (remain <= 0) {
1097 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1098 			goto done;
1099 		}
1100 		s += label_len;
1101 		p = memchr(s, '\n', remain);
1102 		if (p == NULL) {
1103 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1104 			goto done;
1105 		}
1106 		*p = '\0';
1107 		slen = strlen(s);
1108 		(*tag)->tag = strndup(s, slen);
1109 		if ((*tag)->tag == NULL) {
1110 			err = got_error_from_errno("strndup");
1111 			goto done;
1112 		}
1113 		s += slen + 1;
1114 		remain -= slen + 1;
1115 		if (remain <= 0) {
1116 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1117 			goto done;
1118 		}
1119 	} else {
1120 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
1121 		goto done;
1122 	}
1123 
1124 	label_len = strlen(GOT_TAG_LABEL_TAGGER);
1125 	if (strncmp(s, GOT_TAG_LABEL_TAGGER, label_len) == 0) {
1126 		char *p;
1127 		size_t slen;
1128 
1129 		remain -= label_len;
1130 		if (remain <= 0) {
1131 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1132 			goto done;
1133 		}
1134 		s += label_len;
1135 		p = memchr(s, '\n', remain);
1136 		if (p == NULL) {
1137 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1138 			goto done;
1139 		}
1140 		*p = '\0';
1141 		slen = strlen(s);
1142 		err = parse_commit_time(&(*tag)->tagger_time,
1143 		    &(*tag)->tagger_gmtoff, s);
1144 		if (err)
1145 			goto done;
1146 		(*tag)->tagger = strdup(s);
1147 		if ((*tag)->tagger == NULL) {
1148 			err = got_error_from_errno("strdup");
1149 			goto done;
1150 		}
1151 		s += slen + 1;
1152 		remain -= slen + 1;
1153 		if (remain < 0) {
1154 			err = got_error(GOT_ERR_BAD_OBJ_DATA);
1155 			goto done;
1156 		}
1157 	} else {
1158 		/* Some old tags in the Linux git repo have no tagger. */
1159 		(*tag)->tagger = strdup("");
1160 		if ((*tag)->tagger == NULL) {
1161 			err = got_error_from_errno("strdup");
1162 			goto done;
1163 		}
1164 	}
1165 
1166 	(*tag)->tagmsg = strndup(s, remain);
1167 	if ((*tag)->tagmsg == NULL) {
1168 		err = got_error_from_errno("strndup");
1169 		goto done;
1170 	}
1171 done:
1172 	if (err) {
1173 		got_object_tag_close(*tag);
1174 		*tag = NULL;
1175 	}
1176 	return err;
1177 }
1178 
1179 const struct got_error *
1180 got_object_read_tag(struct got_tag_object **tag, int fd,
1181     struct got_object_id *expected_id, size_t expected_size)
1182 {
1183 	const struct got_error *err = NULL;
1184 	struct got_object *obj = NULL;
1185 	size_t len;
1186 	uint8_t *p;
1187 	struct got_inflate_checksum csum;
1188 	struct got_hash ctx;
1189 	struct got_object_id id;
1190 
1191 	got_hash_init(&ctx, GOT_HASH_SHA1);
1192 	memset(&csum, 0, sizeof(csum));
1193 	csum.output_ctx = &ctx;
1194 
1195 	err = got_inflate_to_mem_fd(&p, &len, NULL, &csum,
1196 	    expected_size, fd);
1197 	if (err)
1198 		return err;
1199 
1200 	got_hash_final_object_id(&ctx, &id);
1201 	if (got_object_id_cmp(expected_id, &id) != 0) {
1202 		err = got_error_checksum(expected_id);
1203 		goto done;
1204 	}
1205 
1206 	err = got_object_parse_header(&obj, p, len);
1207 	if (err)
1208 		goto done;
1209 
1210 	if (len < obj->hdrlen + obj->size) {
1211 		err = got_error(GOT_ERR_BAD_OBJ_DATA);
1212 		goto done;
1213 	}
1214 
1215 	/* Skip object header. */
1216 	len -= obj->hdrlen;
1217 	err = got_object_parse_tag(tag, p + obj->hdrlen, len);
1218 done:
1219 	free(p);
1220 	if (obj)
1221 		got_object_close(obj);
1222 	return err;
1223 }
1224 
1225 const struct got_error *
1226 got_read_file_to_mem(uint8_t **outbuf, size_t *outlen, FILE *f)
1227 {
1228 	const struct got_error *err = NULL;
1229 	static const size_t blocksize = 512;
1230 	size_t n, total, remain;
1231 	uint8_t *buf;
1232 
1233 	*outbuf = NULL;
1234 	*outlen = 0;
1235 
1236 	buf = malloc(blocksize);
1237 	if (buf == NULL)
1238 		return got_error_from_errno("malloc");
1239 
1240 	remain = blocksize;
1241 	total = 0;
1242 	for (;;) {
1243 		if (remain == 0) {
1244 			uint8_t *newbuf;
1245 			newbuf = reallocarray(buf, 1, total + blocksize);
1246 			if (newbuf == NULL) {
1247 				err = got_error_from_errno("reallocarray");
1248 				goto done;
1249 			}
1250 			buf = newbuf;
1251 			remain += blocksize;
1252 		}
1253 		n = fread(buf + total, 1, remain, f);
1254 		if (n == 0) {
1255 			if (ferror(f)) {
1256 				err = got_ferror(f, GOT_ERR_IO);
1257 				goto done;
1258 			}
1259 			break; /* EOF */
1260 		}
1261 		remain -= n;
1262 		total += n;
1263 	};
1264 
1265 done:
1266 	if (err == NULL) {
1267 		*outbuf = buf;
1268 		*outlen = total;
1269 	} else
1270 		free(buf);
1271 	return err;
1272 }