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Date:: Thu May 23 12:50:57 2019 UTC
Message:: stat .idx file to determine its size, not the .pack file
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1 /*
2  * Copyright (c) 2018, 2019 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 <sys/types.h>
18 #include <sys/stat.h>
19 #include <sys/queue.h>
20 #include <sys/uio.h>
21 #include <sys/mman.h>
22 
23 #include <fcntl.h>
24 #include <errno.h>
25 #include <stdio.h>
26 #include <stdint.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <limits.h>
30 #include <sha1.h>
31 #include <endian.h>
32 #include <zlib.h>
33 #include <imsg.h>
34 
35 #include "got_error.h"
36 #include "got_object.h"
37 #include "got_opentemp.h"
38 #include "got_path.h"
39 
40 #include "got_lib_sha1.h"
41 #include "got_lib_delta.h"
42 #include "got_lib_inflate.h"
43 #include "got_lib_object.h"
44 #include "got_lib_privsep.h"
45 #include "got_lib_pack.h"
46 
47 #ifndef nitems
48 #define nitems(_a) (sizeof(_a) / sizeof((_a)[0]))
49 #endif
50 
51 #ifndef MIN
52 #define	MIN(_a,_b) ((_a) < (_b) ? (_a) : (_b))
53 #endif
54 
55 static const struct got_error *
56 verify_fanout_table(uint32_t *fanout_table)
57 {
58 	int i;
59 
60 	for (i = 0; i < 0xff - 1; i++) {
61 		if (be32toh(fanout_table[i]) > be32toh(fanout_table[i + 1]))
62 			return got_error(GOT_ERR_BAD_PACKIDX);
63 	}
64 
65 	return NULL;
66 }
67 
68 const struct got_error *
69 got_pack_get_packfile_size(size_t *size, const char *path)
70 {
71 	struct stat sb;
72 	char *dot;
73 
74 	*size = 0;
75 
76 	dot = strrchr(path, '.');
77 	if (dot == NULL)
78 		return got_error(GOT_ERR_BAD_PATH);
79 
80 	/* Path must point to a pack index or to a pack file. */
81 	if (strcmp(dot, GOT_PACKIDX_SUFFIX) == 0) {
82 		const struct got_error *err = NULL;
83 		char *path_pack;
84 		char base_path[PATH_MAX];
85 
86 		/* Convert pack index path to pack file path. */
87 		if (strlcpy(base_path, path, PATH_MAX) > PATH_MAX)
88 			return got_error(GOT_ERR_NO_SPACE);
89 		dot = strrchr(base_path, '.');
90 		if (dot == NULL)
91 			return got_error(GOT_ERR_BAD_PATH);
92 		*dot = '\0';
93 		if (asprintf(&path_pack, "%s.pack", base_path) == -1)
94 			return got_error_from_errno("asprintf");
95 
96 		if (stat(path_pack, &sb) != 0)
97 			err = got_error_from_errno("asprintf");
98 		free(path_pack);
99 		if (err)
100 			return err;
101 	} else if (strcmp(dot, GOT_PACKFILE_SUFFIX) == 0) {
102 		if (stat(path, &sb) != 0)
103 			return got_error_from_errno2("stat", path);
104 	} else
105 		return got_error(GOT_ERR_BAD_PATH);
106 
107 	*size = sb.st_size;
108 	return 0;
109 }
110 
111 const struct got_error *
112 got_packidx_init_hdr(struct got_packidx *p, int verify)
113 {
114 	const struct got_error *err = NULL;
115 	struct got_packidx_v2_hdr *h;
116 	SHA1_CTX ctx;
117 	uint8_t sha1[SHA1_DIGEST_LENGTH];
118 	size_t nobj, len_fanout, len_ids, offset, remain;
119 	ssize_t n;
120 
121 	SHA1Init(&ctx);
122 
123 	h = &p->hdr;
124 	offset = 0;
125 	remain = p->len;
126 
127 	if (remain < sizeof(*h->magic)) {
128 		err = got_error(GOT_ERR_BAD_PACKIDX);
129 		goto done;
130 	}
131 	if (p->map)
132 		h->magic = (uint32_t *)(p->map + offset);
133 	else {
134 		h->magic = malloc(sizeof(*h->magic));
135 		if (h->magic == NULL) {
136 			err = got_error_from_errno("malloc");
137 			goto done;
138 		}
139 		n = read(p->fd, h->magic, sizeof(*h->magic));
140 		if (n < 0)
141 			err = got_error_from_errno("read");
142 		else if (n != sizeof(*h->magic)) {
143 			err = got_error(GOT_ERR_BAD_PACKIDX);
144 			goto done;
145 		}
146 	}
147 	if (betoh32(*h->magic) != GOT_PACKIDX_V2_MAGIC) {
148 		err = got_error(GOT_ERR_BAD_PACKIDX);
149 		goto done;
150 	}
151 	offset += sizeof(*h->magic);
152 	remain -= sizeof(*h->magic);
153 
154 	if (verify)
155 		SHA1Update(&ctx, (uint8_t *)h->magic, sizeof(*h->magic));
156 
157 	if (remain < sizeof(*h->version)) {
158 		err = got_error(GOT_ERR_BAD_PACKIDX);
159 		goto done;
160 	}
161 	if (p->map)
162 		h->version = (uint32_t *)(p->map + offset);
163 	else {
164 		h->version = malloc(sizeof(*h->version));
165 		if (h->version == NULL) {
166 			err = got_error_from_errno("malloc");
167 			goto done;
168 		}
169 		n = read(p->fd, h->version, sizeof(*h->version));
170 		if (n < 0)
171 			err = got_error_from_errno("read");
172 		else if (n != sizeof(*h->version)) {
173 			err = got_error(GOT_ERR_BAD_PACKIDX);
174 			goto done;
175 		}
176 	}
177 	if (betoh32(*h->version) != GOT_PACKIDX_VERSION) {
178 		err = got_error(GOT_ERR_BAD_PACKIDX);
179 		goto done;
180 	}
181 	offset += sizeof(*h->version);
182 	remain -= sizeof(*h->version);
183 
184 	if (verify)
185 		SHA1Update(&ctx, (uint8_t *)h->version, sizeof(*h->version));
186 
187 	len_fanout =
188 	    sizeof(*h->fanout_table) * GOT_PACKIDX_V2_FANOUT_TABLE_ITEMS;
189 	if (remain < len_fanout) {
190 		err = got_error(GOT_ERR_BAD_PACKIDX);
191 		goto done;
192 	}
193 	if (p->map)
194 		h->fanout_table = (uint32_t *)(p->map + offset);
195 	else {
196 		h->fanout_table = malloc(len_fanout);
197 		if (h->fanout_table == NULL) {
198 			err = got_error_from_errno("malloc");
199 			goto done;
200 		}
201 		n = read(p->fd, h->fanout_table, len_fanout);
202 		if (n < 0)
203 			err = got_error_from_errno("read");
204 		else if (n != len_fanout) {
205 			err = got_error(GOT_ERR_BAD_PACKIDX);
206 			goto done;
207 		}
208 	}
209 	err = verify_fanout_table(h->fanout_table);
210 	if (err)
211 		goto done;
212 	if (verify)
213 		SHA1Update(&ctx, (uint8_t *)h->fanout_table, len_fanout);
214 	offset += len_fanout;
215 	remain -= len_fanout;
216 
217 	nobj = betoh32(h->fanout_table[0xff]);
218 	len_ids = nobj * sizeof(*h->sorted_ids);
219 	if (len_ids <= nobj || len_ids > remain) {
220 		err = got_error(GOT_ERR_BAD_PACKIDX);
221 		goto done;
222 	}
223 	if (p->map)
224 		h->sorted_ids =
225 		    (struct got_packidx_object_id *)((uint8_t*)(p->map + offset));
226 	else {
227 		h->sorted_ids = malloc(len_ids);
228 		if (h->sorted_ids == NULL) {
229 			err = got_error(GOT_ERR_BAD_PACKIDX);
230 			goto done;
231 		}
232 		n = read(p->fd, h->sorted_ids, len_ids);
233 		if (n < 0)
234 			err = got_error_from_errno("read");
235 		else if (n != len_ids) {
236 			err = got_error(GOT_ERR_BAD_PACKIDX);
237 			goto done;
238 		}
239 	}
240 	if (verify)
241 		SHA1Update(&ctx, (uint8_t *)h->sorted_ids, len_ids);
242 	offset += len_ids;
243 	remain -= len_ids;
244 
245 	if (remain < nobj * sizeof(*h->crc32)) {
246 		err = got_error(GOT_ERR_BAD_PACKIDX);
247 		goto done;
248 	}
249 	if (p->map)
250 		h->crc32 = (uint32_t *)((uint8_t*)(p->map + offset));
251 	else {
252 		h->crc32 = malloc(nobj * sizeof(*h->crc32));
253 		if (h->crc32 == NULL) {
254 			err = got_error_from_errno("malloc");
255 			goto done;
256 		}
257 		n = read(p->fd, h->crc32, nobj * sizeof(*h->crc32));
258 		if (n < 0)
259 			err = got_error_from_errno("read");
260 		else if (n != nobj * sizeof(*h->crc32)) {
261 			err = got_error(GOT_ERR_BAD_PACKIDX);
262 			goto done;
263 		}
264 	}
265 	if (verify)
266 		SHA1Update(&ctx, (uint8_t *)h->crc32, nobj * sizeof(*h->crc32));
267 	remain -= nobj * sizeof(*h->crc32);
268 	offset += nobj * sizeof(*h->crc32);
269 
270 	if (remain < nobj * sizeof(*h->offsets)) {
271 		err = got_error(GOT_ERR_BAD_PACKIDX);
272 		goto done;
273 	}
274 	if (p->map)
275 		h->offsets = (uint32_t *)((uint8_t*)(p->map + offset));
276 	else {
277 		h->offsets = malloc(nobj * sizeof(*h->offsets));
278 		if (h->offsets == NULL) {
279 			err = got_error_from_errno("malloc");
280 			goto done;
281 		}
282 		n = read(p->fd, h->offsets, nobj * sizeof(*h->offsets));
283 		if (n < 0)
284 			err = got_error_from_errno("read");
285 		else if (n != nobj * sizeof(*h->offsets)) {
286 			err = got_error(GOT_ERR_BAD_PACKIDX);
287 			goto done;
288 		}
289 	}
290 	if (verify)
291 		SHA1Update(&ctx, (uint8_t *)h->offsets,
292 		    nobj * sizeof(*h->offsets));
293 	remain -= nobj * sizeof(*h->offsets);
294 	offset += nobj * sizeof(*h->offsets);
295 
296 	/* Large file offsets are contained only in files > 2GB. */
297 	if (p->len <= 0x80000000)
298 		goto checksum;
299 
300 	if (remain < nobj * sizeof(*h->large_offsets)) {
301 		err = got_error(GOT_ERR_BAD_PACKIDX);
302 		goto done;
303 	}
304 	if (p->map)
305 		h->large_offsets = (uint64_t *)((uint8_t*)(p->map + offset));
306 	else {
307 		h->offsets = malloc(nobj * sizeof(*h->large_offsets));
308 		if (h->offsets == NULL) {
309 			err = got_error_from_errno("malloc");
310 			goto done;
311 		}
312 		n = read(p->fd, h->large_offsets,
313 		    nobj * sizeof(*h->large_offsets));
314 		if (n < 0)
315 			err = got_error_from_errno("read");
316 		else if (n != nobj * sizeof(*h->large_offsets)) {
317 			err = got_error(GOT_ERR_BAD_PACKIDX);
318 			goto done;
319 		}
320 	}
321 	if (verify)
322 		SHA1Update(&ctx, (uint8_t*)h->large_offsets,
323 		    nobj * sizeof(*h->large_offsets));
324 	remain -= nobj * sizeof(*h->large_offsets);
325 	offset += nobj * sizeof(*h->large_offsets);
326 
327 checksum:
328 	if (remain < sizeof(*h->trailer)) {
329 		err = got_error(GOT_ERR_BAD_PACKIDX);
330 		goto done;
331 	}
332 	if (p->map)
333 		h->trailer =
334 		    (struct got_packidx_trailer *)((uint8_t*)(p->map + offset));
335 	else {
336 		h->trailer = malloc(sizeof(*h->trailer));
337 		if (h->trailer == NULL) {
338 			err = got_error_from_errno("malloc");
339 			goto done;
340 		}
341 		n = read(p->fd, h->trailer, sizeof(*h->trailer));
342 		if (n < 0)
343 			err = got_error_from_errno("read");
344 		else if (n != sizeof(*h->trailer)) {
345 			err = got_error(GOT_ERR_BAD_PACKIDX);
346 			goto done;
347 		}
348 	}
349 	if (verify) {
350 		SHA1Update(&ctx, h->trailer->packfile_sha1, SHA1_DIGEST_LENGTH);
351 		SHA1Final(sha1, &ctx);
352 		if (memcmp(h->trailer->packidx_sha1, sha1,
353 		    SHA1_DIGEST_LENGTH) != 0)
354 			err = got_error(GOT_ERR_PACKIDX_CSUM);
355 	}
356 done:
357 	return err;
358 }
359 
360 const struct got_error *
361 got_packidx_open(struct got_packidx **packidx, const char *path, int verify)
362 {
363 	const struct got_error *err = NULL;
364 	struct got_packidx *p;
365 	struct stat sb;
366 
367 	*packidx = NULL;
368 
369 	p = calloc(1, sizeof(*p));
370 	if (p == NULL)
371 		return got_error_from_errno("calloc");
372 
373 	p->fd = open(path, O_RDONLY | O_NOFOLLOW);
374 	if (p->fd == -1)
375 		return got_error_from_errno2("open", path);
376 
377 	if (fstat(p->fd, &sb) != 0) {
378 		err = got_error_from_errno2("fstat", path);
379 		close(p->fd);
380 		free(p);
381 		return err;
382 	}
383 	p->len = sb.st_size;
384 	if (p->len < sizeof(p->hdr)) {
385 		err = got_error(GOT_ERR_BAD_PACKIDX);
386 		close(p->fd);
387 		free(p);
388 		return err;
389 	}
390 
391 	p->path_packidx = strdup(path);
392 	if (p->path_packidx == NULL) {
393 		err = got_error_from_errno("strdup");
394 		goto done;
395 	}
396 
397 #ifndef GOT_PACK_NO_MMAP
398 	p->map = mmap(NULL, p->len, PROT_READ, MAP_PRIVATE, p->fd, 0);
399 	if (p->map == MAP_FAILED) {
400 		if (errno != ENOMEM) {
401 			err = got_error_from_errno("mmap");
402 			goto done;
403 		}
404 		p->map = NULL; /* fall back to read(2) */
405 	}
406 #endif
407 
408 	err = got_packidx_init_hdr(p, verify);
409 done:
410 	if (err)
411 		got_packidx_close(p);
412 	else
413 		*packidx = p;
414 
415 	return err;
416 }
417 
418 const struct got_error *
419 got_packidx_close(struct got_packidx *packidx)
420 {
421 	const struct got_error *err = NULL;
422 
423 	free(packidx->path_packidx);
424 	if (packidx->map) {
425 		if (munmap(packidx->map, packidx->len) == -1)
426 			err = got_error_from_errno("munmap");
427 	} else {
428 		free(packidx->hdr.magic);
429 		free(packidx->hdr.version);
430 		free(packidx->hdr.fanout_table);
431 		free(packidx->hdr.sorted_ids);
432 		free(packidx->hdr.crc32);
433 		free(packidx->hdr.offsets);
434 		free(packidx->hdr.large_offsets);
435 		free(packidx->hdr.trailer);
436 	}
437 	if (close(packidx->fd) != 0 && err == NULL)
438 		err = got_error_from_errno("close");
439 	free(packidx);
440 
441 	return err;
442 }
443 
444 static off_t
445 get_object_offset(struct got_packidx *packidx, int idx)
446 {
447 	uint32_t totobj = betoh32(packidx->hdr.fanout_table[0xff]);
448 	uint32_t offset = betoh32(packidx->hdr.offsets[idx]);
449 	if (offset & GOT_PACKIDX_OFFSET_VAL_IS_LARGE_IDX) {
450 		uint64_t loffset;
451 		idx = offset & GOT_PACKIDX_OFFSET_VAL_MASK;
452 		if (idx < 0 || idx > totobj ||
453 		    packidx->hdr.large_offsets == NULL)
454 			return -1;
455 		loffset = betoh64(packidx->hdr.large_offsets[idx]);
456 		return (loffset > INT64_MAX ? -1 : (off_t)loffset);
457 	}
458 	return (off_t)(offset & GOT_PACKIDX_OFFSET_VAL_MASK);
459 }
460 
461 int
462 got_packidx_get_object_idx(struct got_packidx *packidx, struct got_object_id *id)
463 {
464 	u_int8_t id0 = id->sha1[0];
465 	uint32_t totobj = betoh32(packidx->hdr.fanout_table[0xff]);
466 	int left = 0, right = totobj - 1;
467 
468 	if (id0 > 0)
469 		left = betoh32(packidx->hdr.fanout_table[id0 - 1]);
470 
471 	while (left <= right) {
472 		struct got_packidx_object_id *oid;
473 		int i, cmp;
474 
475 		i = ((left + right) / 2);
476 		oid = &packidx->hdr.sorted_ids[i];
477 		cmp = memcmp(id->sha1, oid->sha1, SHA1_DIGEST_LENGTH);
478 		if (cmp == 0)
479 			return i;
480 		else if (cmp > 0)
481 			left = i + 1;
482 		else if (cmp < 0)
483 			right = i - 1;
484 	}
485 
486 	return -1;
487 }
488 
489 const struct got_error *
490 got_pack_stop_privsep_child(struct got_pack *pack)
491 {
492 	const struct got_error *err = NULL;
493 
494 	if (pack->privsep_child == NULL)
495 		return NULL;
496 
497 	err = got_privsep_send_stop(pack->privsep_child->imsg_fd);
498 	if (err)
499 		return err;
500 	err = got_privsep_wait_for_child(pack->privsep_child->pid);
501 	if (close(pack->privsep_child->imsg_fd) != 0 && err == NULL)
502 		err = got_error_from_errno("close");
503 	free(pack->privsep_child);
504 	pack->privsep_child = NULL;
505 	return err;
506 }
507 
508 const struct got_error *
509 got_pack_close(struct got_pack *pack)
510 {
511 	const struct got_error *err = NULL;
512 
513 	err = got_pack_stop_privsep_child(pack);
514 	if (pack->map && munmap(pack->map, pack->filesize) == -1 && !err)
515 		err = got_error_from_errno("munmap");
516 	if (pack->fd != -1 && close(pack->fd) != 0 && err == NULL)
517 		err = got_error_from_errno("close");
518 	pack->fd = -1;
519 	free(pack->path_packfile);
520 	pack->path_packfile = NULL;
521 	pack->filesize = 0;
522 
523 	return err;
524 }
525 
526 static const struct got_error *
527 parse_object_type_and_size(uint8_t *type, uint64_t *size, size_t *len,
528     struct got_pack *pack, off_t offset)
529 {
530 	uint8_t t = 0;
531 	uint64_t s = 0;
532 	uint8_t sizeN;
533 	size_t mapoff = 0;
534 	int i = 0;
535 
536 	*len = 0;
537 
538 	if (offset >= pack->filesize)
539 		return got_error(GOT_ERR_PACK_OFFSET);
540 
541 	if (pack->map) {
542 		mapoff = (size_t)offset;
543 	} else {
544 		if (lseek(pack->fd, offset, SEEK_SET) == -1)
545 			return got_error_from_errno("lseek");
546 	}
547 
548 	do {
549 		/* We do not support size values which don't fit in 64 bit. */
550 		if (i > 9)
551 			return got_error(GOT_ERR_NO_SPACE);
552 
553 		if (pack->map) {
554 			sizeN = *(pack->map + mapoff);
555 			mapoff += sizeof(sizeN);
556 		} else {
557 			ssize_t n = read(pack->fd, &sizeN, sizeof(sizeN));
558 			if (n < 0)
559 				return got_error_from_errno("read");
560 			if (n != sizeof(sizeN))
561 				return got_error(GOT_ERR_BAD_PACKFILE);
562 		}
563 		*len += sizeof(sizeN);
564 
565 		if (i == 0) {
566 			t = (sizeN & GOT_PACK_OBJ_SIZE0_TYPE_MASK) >>
567 			    GOT_PACK_OBJ_SIZE0_TYPE_MASK_SHIFT;
568 			s = (sizeN & GOT_PACK_OBJ_SIZE0_VAL_MASK);
569 		} else {
570 			size_t shift = 4 + 7 * (i - 1);
571 			s |= ((sizeN & GOT_PACK_OBJ_SIZE_VAL_MASK) << shift);
572 		}
573 		i++;
574 	} while (sizeN & GOT_PACK_OBJ_SIZE_MORE);
575 
576 	*type = t;
577 	*size = s;
578 	return NULL;
579 }
580 
581 static const struct got_error *
582 open_plain_object(struct got_object **obj, const char *path_packfile,
583     struct got_object_id *id, uint8_t type, off_t offset, size_t size, int idx)
584 {
585 	*obj = calloc(1, sizeof(**obj));
586 	if (*obj == NULL)
587 		return got_error_from_errno("calloc");
588 
589 	(*obj)->path_packfile = strdup(path_packfile);
590 	if ((*obj)->path_packfile == NULL) {
591 		const struct got_error *err = got_error_from_errno("strdup");
592 		free(*obj);
593 		*obj = NULL;
594 		return err;
595 	}
596 
597 	(*obj)->type = type;
598 	(*obj)->flags = GOT_OBJ_FLAG_PACKED;
599 	(*obj)->pack_idx = idx;
600 	(*obj)->hdrlen = 0;
601 	(*obj)->size = size;
602 	memcpy(&(*obj)->id, id, sizeof((*obj)->id));
603 	(*obj)->pack_offset = offset;
604 
605 	return NULL;
606 }
607 
608 static const struct got_error *
609 parse_negative_offset(int64_t *offset, size_t *len, struct got_pack *pack,
610     off_t delta_offset)
611 {
612 	int64_t o = 0;
613 	uint8_t offN;
614 	int i = 0;
615 
616 	*len = 0;
617 
618 	do {
619 		/* We do not support offset values which don't fit in 64 bit. */
620 		if (i > 8)
621 			return got_error(GOT_ERR_NO_SPACE);
622 
623 		if (pack->map) {
624 			size_t mapoff;
625 			if (delta_offset >= pack->filesize)
626 				return got_error(GOT_ERR_PACK_OFFSET);
627 			mapoff = (size_t)delta_offset + *len;
628 			offN = *(pack->map + mapoff);
629 		} else {
630 			ssize_t n;
631 			n = read(pack->fd, &offN, sizeof(offN));
632 			if (n < 0)
633 				return got_error_from_errno("read");
634 			if (n != sizeof(offN))
635 				return got_error(GOT_ERR_BAD_PACKFILE);
636 		}
637 		*len += sizeof(offN);
638 
639 		if (i == 0)
640 			o = (offN & GOT_PACK_OBJ_DELTA_OFF_VAL_MASK);
641 		else {
642 			o++;
643 			o <<= 7;
644 			o += (offN & GOT_PACK_OBJ_DELTA_OFF_VAL_MASK);
645 		}
646 		i++;
647 	} while (offN & GOT_PACK_OBJ_DELTA_OFF_MORE);
648 
649 	*offset = o;
650 	return NULL;
651 }
652 
653 static const struct got_error *
654 parse_offset_delta(off_t *base_offset, size_t *len, struct got_pack *pack,
655     off_t offset, int tslen)
656 {
657 	const struct got_error *err;
658 	int64_t negoffset;
659 	size_t negofflen;
660 
661 	*len = 0;
662 
663 	err = parse_negative_offset(&negoffset, &negofflen, pack,
664 	    offset + tslen);
665 	if (err)
666 		return err;
667 
668 	/* Compute the base object's offset (must be in the same pack file). */
669 	*base_offset = (offset - negoffset);
670 	if (*base_offset <= 0)
671 		return got_error(GOT_ERR_BAD_PACKFILE);
672 
673 	*len = negofflen;
674 	return NULL;
675 }
676 
677 static const struct got_error *
678 resolve_delta_chain(struct got_delta_chain *, struct got_packidx *,
679     struct got_pack *, off_t, size_t, int, size_t, unsigned int);
680 
681 static const struct got_error *
682 add_delta(struct got_delta_chain *deltas, off_t delta_offset, size_t tslen,
683     int delta_type, size_t delta_size, size_t delta_data_offset,
684     uint8_t *delta_buf, size_t delta_len)
685 {
686 	struct got_delta *delta;
687 
688 	delta = got_delta_open(delta_offset, tslen, delta_type, delta_size,
689 	    delta_data_offset, delta_buf,
690 	    delta_len);
691 	if (delta == NULL)
692 		return got_error_from_errno("got_delta_open");
693 	/* delta is freed in got_object_close() */
694 	deltas->nentries++;
695 	SIMPLEQ_INSERT_HEAD(&deltas->entries, delta, entry);
696 	return NULL;
697 }
698 
699 static const struct got_error *
700 resolve_offset_delta(struct got_delta_chain *deltas,
701     struct got_packidx *packidx, struct got_pack *pack, off_t delta_offset,
702     size_t tslen, int delta_type, size_t delta_size, unsigned int recursion)
703 
704 {
705 	const struct got_error *err;
706 	off_t base_offset;
707 	uint8_t base_type;
708 	uint64_t base_size;
709 	size_t base_tslen;
710 	off_t delta_data_offset;
711 	uint8_t *delta_buf;
712 	size_t delta_len, consumed;
713 
714 	err = parse_offset_delta(&base_offset, &consumed, pack,
715 	    delta_offset, tslen);
716 	if (err)
717 		return err;
718 
719 	delta_data_offset = delta_offset + tslen + consumed;
720 	if (delta_data_offset >= pack->filesize)
721 		return got_error(GOT_ERR_PACK_OFFSET);
722 
723 	if (pack->map == NULL) {
724 		delta_data_offset = lseek(pack->fd, 0, SEEK_CUR);
725 		if (delta_data_offset == -1)
726 			return got_error_from_errno("lseek");
727 	}
728 
729 	if (pack->map) {
730 		size_t mapoff = (size_t)delta_data_offset;
731 		err = got_inflate_to_mem_mmap(&delta_buf, &delta_len, pack->map,
732 		    mapoff, pack->filesize - mapoff);
733 		if (err)
734 			return err;
735 	} else {
736 
737 		err = got_inflate_to_mem_fd(&delta_buf, &delta_len, pack->fd);
738 		if (err)
739 			return err;
740 	}
741 
742 	err = add_delta(deltas, delta_offset, tslen, delta_type, delta_size,
743 	    delta_data_offset, delta_buf, delta_len);
744 	if (err)
745 		return err;
746 
747 	/* An offset delta must be in the same packfile. */
748 	if (base_offset >= pack->filesize)
749 		return got_error(GOT_ERR_PACK_OFFSET);
750 
751 	err = parse_object_type_and_size(&base_type, &base_size, &base_tslen,
752 	    pack, base_offset);
753 	if (err)
754 		return err;
755 
756 	return resolve_delta_chain(deltas, packidx, pack, base_offset,
757 	    base_tslen, base_type, base_size, recursion - 1);
758 }
759 
760 static const struct got_error *
761 resolve_ref_delta(struct got_delta_chain *deltas, struct got_packidx *packidx,
762     struct got_pack *pack, off_t delta_offset, size_t tslen, int delta_type,
763     size_t delta_size, unsigned int recursion)
764 {
765 	const struct got_error *err;
766 	struct got_object_id id;
767 	int idx;
768 	off_t base_offset;
769 	uint8_t base_type;
770 	uint64_t base_size;
771 	size_t base_tslen;
772 	off_t delta_data_offset;
773 	uint8_t *delta_buf;
774 	size_t delta_len;
775 
776 	if (delta_offset >= pack->filesize)
777 		return got_error(GOT_ERR_PACK_OFFSET);
778 	delta_data_offset = delta_offset + tslen;
779 	if (delta_data_offset >= pack->filesize)
780 		return got_error(GOT_ERR_PACK_OFFSET);
781 
782 	if (pack->map == NULL) {
783 		delta_data_offset = lseek(pack->fd, 0, SEEK_CUR);
784 		if (delta_data_offset == -1)
785 			return got_error_from_errno("lseek");
786 	}
787 
788 	if (pack->map) {
789 		size_t mapoff = (size_t)delta_data_offset;
790 		memcpy(&id, pack->map + mapoff, sizeof(id));
791 		mapoff += sizeof(id);
792 		err = got_inflate_to_mem_mmap(&delta_buf, &delta_len, pack->map,
793 		    mapoff, pack->filesize - mapoff);
794 		if (err)
795 			return err;
796 	} else {
797 		ssize_t n = read(pack->fd, &id, sizeof(id));
798 		if (n < 0)
799 			return got_error_from_errno("read");
800 		if (n != sizeof(id))
801 			return got_error(GOT_ERR_BAD_PACKFILE);
802 		err = got_inflate_to_mem_fd(&delta_buf, &delta_len, pack->fd);
803 		if (err)
804 			return err;
805 	}
806 
807 	err = add_delta(deltas, delta_offset, tslen, delta_type, delta_size,
808 	    delta_data_offset, delta_buf, delta_len);
809 	if (err)
810 		return err;
811 
812 	/* Delta base must be in the same pack file. */
813 	idx = got_packidx_get_object_idx(packidx, &id);
814 	if (idx == -1)
815 		return got_error(GOT_ERR_BAD_PACKFILE);
816 
817 	base_offset = get_object_offset(packidx, idx);
818 	if (base_offset == (uint64_t)-1)
819 		return got_error(GOT_ERR_BAD_PACKIDX);
820 
821 	if (base_offset >= pack->filesize)
822 		return got_error(GOT_ERR_PACK_OFFSET);
823 
824 	err = parse_object_type_and_size(&base_type, &base_size, &base_tslen,
825 	    pack, base_offset);
826 	if (err)
827 		return err;
828 
829 	return resolve_delta_chain(deltas, packidx, pack, base_offset,
830 	    base_tslen, base_type, base_size, recursion - 1);
831 }
832 
833 static const struct got_error *
834 resolve_delta_chain(struct got_delta_chain *deltas, struct got_packidx *packidx,
835     struct got_pack *pack, off_t delta_offset, size_t tslen, int delta_type,
836     size_t delta_size, unsigned int recursion)
837 {
838 	const struct got_error *err = NULL;
839 
840 	if (--recursion == 0)
841 		return got_error(GOT_ERR_RECURSION);
842 
843 	switch (delta_type) {
844 	case GOT_OBJ_TYPE_COMMIT:
845 	case GOT_OBJ_TYPE_TREE:
846 	case GOT_OBJ_TYPE_BLOB:
847 	case GOT_OBJ_TYPE_TAG:
848 		/* Plain types are the final delta base. Recursion ends. */
849 		err = add_delta(deltas, delta_offset, tslen, delta_type,
850 		    delta_size, 0, NULL, 0);
851 		break;
852 	case GOT_OBJ_TYPE_OFFSET_DELTA:
853 		err = resolve_offset_delta(deltas, packidx, pack,
854 		    delta_offset, tslen, delta_type, delta_size, recursion - 1);
855 		break;
856 	case GOT_OBJ_TYPE_REF_DELTA:
857 		err = resolve_ref_delta(deltas, packidx, pack,
858 		    delta_offset, tslen, delta_type, delta_size, recursion - 1);
859 		break;
860 	default:
861 		return got_error(GOT_ERR_OBJ_TYPE);
862 	}
863 
864 	return err;
865 }
866 
867 static const struct got_error *
868 open_delta_object(struct got_object **obj, struct got_packidx *packidx,
869     struct got_pack *pack, struct got_object_id *id, off_t offset,
870     size_t tslen, int delta_type, size_t delta_size, int idx)
871 {
872 	const struct got_error *err = NULL;
873 	int resolved_type;
874 
875 	*obj = calloc(1, sizeof(**obj));
876 	if (*obj == NULL)
877 		return got_error_from_errno("calloc");
878 
879 	(*obj)->flags = 0;
880 	(*obj)->hdrlen = 0;
881 	(*obj)->size = 0; /* Not known because deltas aren't applied yet. */
882 	memcpy(&(*obj)->id, id, sizeof((*obj)->id));
883 	(*obj)->pack_offset = offset + tslen;
884 
885 	SIMPLEQ_INIT(&(*obj)->deltas.entries);
886 	(*obj)->flags |= GOT_OBJ_FLAG_DELTIFIED;
887 
888 	(*obj)->path_packfile = strdup(pack->path_packfile);
889 	if ((*obj)->path_packfile == NULL) {
890 		err = got_error_from_errno("strdup");
891 		goto done;
892 	}
893 	(*obj)->flags |= GOT_OBJ_FLAG_PACKED;
894 	(*obj)->pack_idx = idx;
895 
896 	err = resolve_delta_chain(&(*obj)->deltas, packidx, pack, offset,
897 	    tslen, delta_type, delta_size, GOT_DELTA_CHAIN_RECURSION_MAX);
898 	if (err)
899 		goto done;
900 
901 	err = got_delta_chain_get_base_type(&resolved_type, &(*obj)->deltas);
902 	if (err)
903 		goto done;
904 	(*obj)->type = resolved_type;
905 done:
906 	if (err) {
907 		got_object_close(*obj);
908 		*obj = NULL;
909 	}
910 	return err;
911 }
912 
913 const struct got_error *
914 got_packfile_open_object(struct got_object **obj, struct got_pack *pack,
915     struct got_packidx *packidx, int idx, struct got_object_id *id)
916 {
917 	const struct got_error *err = NULL;
918 	off_t offset;
919 	uint8_t type;
920 	uint64_t size;
921 	size_t tslen;
922 
923 	*obj = NULL;
924 
925 	offset = get_object_offset(packidx, idx);
926 	if (offset == (uint64_t)-1)
927 		return got_error(GOT_ERR_BAD_PACKIDX);
928 
929 	err = parse_object_type_and_size(&type, &size, &tslen, pack, offset);
930 	if (err)
931 		return err;
932 
933 	switch (type) {
934 	case GOT_OBJ_TYPE_COMMIT:
935 	case GOT_OBJ_TYPE_TREE:
936 	case GOT_OBJ_TYPE_BLOB:
937 	case GOT_OBJ_TYPE_TAG:
938 		err = open_plain_object(obj, pack->path_packfile, id, type,
939 		    offset + tslen, size, idx);
940 		break;
941 	case GOT_OBJ_TYPE_OFFSET_DELTA:
942 	case GOT_OBJ_TYPE_REF_DELTA:
943 		err = open_delta_object(obj, packidx, pack, id, offset,
944 		    tslen, type, size, idx);
945 		break;
946 	default:
947 		err = got_error(GOT_ERR_OBJ_TYPE);
948 		break;
949 	}
950 
951 	return err;
952 }
953 
954 static const struct got_error *
955 get_delta_chain_max_size(uint64_t *max_size, struct got_delta_chain *deltas)
956 {
957 	struct got_delta *delta;
958 	uint64_t base_size = 0, result_size = 0;
959 
960 	*max_size = 0;
961 	SIMPLEQ_FOREACH(delta, &deltas->entries, entry) {
962 		/* Plain object types are the delta base. */
963 		if (delta->type != GOT_OBJ_TYPE_COMMIT &&
964 		    delta->type != GOT_OBJ_TYPE_TREE &&
965 		    delta->type != GOT_OBJ_TYPE_BLOB &&
966 		    delta->type != GOT_OBJ_TYPE_TAG) {
967 			const struct got_error *err;
968 			err = got_delta_get_sizes(&base_size, &result_size,
969 			    delta->delta_buf, delta->delta_len);
970 			if (err)
971 				return err;
972 		} else
973 			base_size = delta->size;
974 		if (base_size > *max_size)
975 			*max_size = base_size;
976 		if (result_size > *max_size)
977 			*max_size = result_size;
978 	}
979 
980 	return NULL;
981 }
982 
983 const struct got_error *
984 got_pack_get_max_delta_object_size(uint64_t *size, struct got_object *obj)
985 {
986 	if ((obj->flags & GOT_OBJ_FLAG_DELTIFIED) == 0)
987 		return got_error(GOT_ERR_OBJ_TYPE);
988 
989 	return get_delta_chain_max_size(size, &obj->deltas);
990 }
991 
992 static const struct got_error *
993 dump_delta_chain_to_file(size_t *result_size, struct got_delta_chain *deltas,
994     struct got_pack *pack, FILE *outfile, FILE *base_file, FILE *accum_file)
995 {
996 	const struct got_error *err = NULL;
997 	struct got_delta *delta;
998 	uint8_t *base_buf = NULL, *accum_buf = NULL;
999 	size_t base_bufsz = 0, accum_size = 0;
1000 	uint64_t max_size;
1001 	int n = 0;
1002 
1003 	*result_size = 0;
1004 
1005 	if (SIMPLEQ_EMPTY(&deltas->entries))
1006 		return got_error(GOT_ERR_BAD_DELTA_CHAIN);
1007 
1008 	/* We process small enough files entirely in memory for speed. */
1009 	err = get_delta_chain_max_size(&max_size, deltas);
1010 	if (err)
1011 		return err;
1012 	if (max_size < GOT_DELTA_RESULT_SIZE_CACHED_MAX) {
1013 		accum_buf = malloc(max_size);
1014 		if (accum_buf == NULL)
1015 			return got_error_from_errno("malloc");
1016 		base_file = NULL;
1017 		accum_file = NULL;
1018 	}
1019 
1020 	/* Deltas are ordered in ascending order. */
1021 	SIMPLEQ_FOREACH(delta, &deltas->entries, entry) {
1022 		if (n == 0) {
1023 			size_t mapoff;
1024 			off_t delta_data_offset;
1025 
1026 			/* Plain object types are the delta base. */
1027 			if (delta->type != GOT_OBJ_TYPE_COMMIT &&
1028 			    delta->type != GOT_OBJ_TYPE_TREE &&
1029 			    delta->type != GOT_OBJ_TYPE_BLOB &&
1030 			    delta->type != GOT_OBJ_TYPE_TAG) {
1031 				err = got_error(GOT_ERR_BAD_DELTA_CHAIN);
1032 				goto done;
1033 			}
1034 
1035 			delta_data_offset = delta->offset + delta->tslen;
1036 			if (delta_data_offset >= pack->filesize) {
1037 				err = got_error(GOT_ERR_PACK_OFFSET);
1038 				goto done;
1039 			}
1040 			if (pack->map == NULL) {
1041 				if (lseek(pack->fd, delta_data_offset, SEEK_SET)
1042 				    == -1) {
1043 					err = got_error_from_errno("lseek");
1044 					goto done;
1045 				}
1046 			}
1047 			if (base_file) {
1048 				if (pack->map) {
1049 					mapoff = (size_t)delta_data_offset;
1050 					err = got_inflate_to_file_mmap(
1051 					    &base_bufsz, pack->map, mapoff,
1052 					    pack->filesize - mapoff, base_file);
1053 				} else
1054 					err = got_inflate_to_file_fd(
1055 					    &base_bufsz, pack->fd, base_file);
1056 			} else {
1057 				if (pack->map) {
1058 					mapoff = (size_t)delta_data_offset;
1059 					err = got_inflate_to_mem_mmap(&base_buf,
1060 					    &base_bufsz, pack->map, mapoff,
1061 					    pack->filesize - mapoff);
1062 				} else
1063 					err = got_inflate_to_mem_fd(&base_buf,
1064 					    &base_bufsz, pack->fd);
1065 			}
1066 			if (err)
1067 				goto done;
1068 			n++;
1069 			if (base_file)
1070 				rewind(base_file);
1071 			continue;
1072 		}
1073 
1074 		if (base_buf) {
1075 			err = got_delta_apply_in_mem(base_buf, base_bufsz,
1076 			    delta->delta_buf, delta->delta_len, accum_buf,
1077 			    &accum_size, max_size);
1078 			n++;
1079 		} else {
1080 			err = got_delta_apply(base_file, delta->delta_buf,
1081 			    delta->delta_len,
1082 			    /* Final delta application writes to output file. */
1083 			    ++n < deltas->nentries ? accum_file : outfile,
1084 			    &accum_size);
1085 		}
1086 		if (err)
1087 			goto done;
1088 
1089 		if (n < deltas->nentries) {
1090 			/* Accumulated delta becomes the new base. */
1091 			if (base_buf) {
1092 				uint8_t *tmp = accum_buf;
1093 				/*
1094 				 * Base buffer switches roles with accumulation
1095 				 * buffer. Ensure it can hold the largest
1096 				 * result in the delta chain. The initial
1097 				 * allocation might have been smaller.
1098 				 */
1099 				if (base_bufsz < max_size) {
1100 					uint8_t *p;
1101 					p = reallocarray(base_buf, 1, max_size);
1102 					if (p == NULL) {
1103 						err = got_error_from_errno(
1104 						    "reallocarray");
1105 						goto done;
1106 					}
1107 					base_buf = p;
1108 					base_bufsz = max_size;
1109 				}
1110 				accum_buf = base_buf;
1111 				base_buf = tmp;
1112 			} else {
1113 				FILE *tmp = accum_file;
1114 				accum_file = base_file;
1115 				base_file = tmp;
1116 				rewind(base_file);
1117 				rewind(accum_file);
1118 			}
1119 		}
1120 	}
1121 
1122 done:
1123 	free(base_buf);
1124 	if (accum_buf) {
1125 		size_t len = fwrite(accum_buf, 1, accum_size, outfile);
1126 		free(accum_buf);
1127 		if (len != accum_size)
1128 			err = got_ferror(outfile, GOT_ERR_IO);
1129 	}
1130 	rewind(outfile);
1131 	if (err == NULL)
1132 		*result_size = accum_size;
1133 	return err;
1134 }
1135 
1136 static const struct got_error *
1137 dump_delta_chain_to_mem(uint8_t **outbuf, size_t *outlen,
1138     struct got_delta_chain *deltas, struct got_pack *pack)
1139 {
1140 	const struct got_error *err = NULL;
1141 	struct got_delta *delta;
1142 	uint8_t *base_buf = NULL, *accum_buf = NULL;
1143 	size_t base_bufsz = 0, accum_size = 0;
1144 	uint64_t max_size;
1145 	int n = 0;
1146 
1147 	*outbuf = NULL;
1148 	*outlen = 0;
1149 
1150 	if (SIMPLEQ_EMPTY(&deltas->entries))
1151 		return got_error(GOT_ERR_BAD_DELTA_CHAIN);
1152 
1153 	err = get_delta_chain_max_size(&max_size, deltas);
1154 	if (err)
1155 		return err;
1156 	accum_buf = malloc(max_size);
1157 	if (accum_buf == NULL)
1158 		return got_error_from_errno("malloc");
1159 
1160 	/* Deltas are ordered in ascending order. */
1161 	SIMPLEQ_FOREACH(delta, &deltas->entries, entry) {
1162 		if (n == 0) {
1163 			size_t delta_data_offset;
1164 
1165 			/* Plain object types are the delta base. */
1166 			if (delta->type != GOT_OBJ_TYPE_COMMIT &&
1167 			    delta->type != GOT_OBJ_TYPE_TREE &&
1168 			    delta->type != GOT_OBJ_TYPE_BLOB &&
1169 			    delta->type != GOT_OBJ_TYPE_TAG) {
1170 				err = got_error(GOT_ERR_BAD_DELTA_CHAIN);
1171 				goto done;
1172 			}
1173 
1174 			delta_data_offset = delta->offset + delta->tslen;
1175 			if (delta_data_offset >= pack->filesize) {
1176 				err = got_error(GOT_ERR_PACK_OFFSET);
1177 				goto done;
1178 			}
1179 			if (pack->map) {
1180 				size_t mapoff = (size_t)delta_data_offset;
1181 				err = got_inflate_to_mem_mmap(&base_buf,
1182 				    &base_bufsz, pack->map, mapoff,
1183 				    pack->filesize - mapoff);
1184 			} else {
1185 				if (lseek(pack->fd, delta_data_offset, SEEK_SET)
1186 				    == -1) {
1187 					err = got_error_from_errno("lseek");
1188 					goto done;
1189 				}
1190 				err = got_inflate_to_mem_fd(&base_buf,
1191 				    &base_bufsz, pack->fd);
1192 			}
1193 			if (err)
1194 				goto done;
1195 			n++;
1196 			continue;
1197 		}
1198 
1199 		err = got_delta_apply_in_mem(base_buf, base_bufsz,
1200 		    delta->delta_buf, delta->delta_len, accum_buf,
1201 		    &accum_size, max_size);
1202 		n++;
1203 		if (err)
1204 			goto done;
1205 
1206 		if (n < deltas->nentries) {
1207 			/* Accumulated delta becomes the new base. */
1208 			uint8_t *tmp = accum_buf;
1209 			/*
1210 			 * Base buffer switches roles with accumulation buffer.
1211 			 * Ensure it can hold the largest result in the delta
1212 			 * chain. Initial allocation might have been smaller.
1213 			 */
1214 			if (base_bufsz < max_size) {
1215 				uint8_t *p;
1216 				p = reallocarray(base_buf, 1, max_size);
1217 				if (p == NULL) {
1218 					err = got_error_from_errno(
1219 					    "reallocarray");
1220 					goto done;
1221 				}
1222 				base_buf = p;
1223 				base_bufsz = max_size;
1224 			}
1225 			accum_buf = base_buf;
1226 			base_buf = tmp;
1227 		}
1228 	}
1229 
1230 done:
1231 	free(base_buf);
1232 	if (err) {
1233 		free(accum_buf);
1234 		*outbuf = NULL;
1235 		*outlen = 0;
1236 	} else {
1237 		*outbuf = accum_buf;
1238 		*outlen = accum_size;
1239 	}
1240 	return err;
1241 }
1242 
1243 const struct got_error *
1244 got_packfile_extract_object(struct got_pack *pack, struct got_object *obj,
1245     FILE *outfile, FILE *base_file, FILE *accum_file)
1246 {
1247 	const struct got_error *err = NULL;
1248 
1249 	if ((obj->flags & GOT_OBJ_FLAG_PACKED) == 0)
1250 		return got_error(GOT_ERR_OBJ_NOT_PACKED);
1251 
1252 	if ((obj->flags & GOT_OBJ_FLAG_DELTIFIED) == 0) {
1253 		if (obj->pack_offset >= pack->filesize)
1254 			return got_error(GOT_ERR_PACK_OFFSET);
1255 
1256 		if (pack->map) {
1257 			size_t mapoff = (size_t)obj->pack_offset;
1258 			err = got_inflate_to_file_mmap(&obj->size, pack->map,
1259 			    mapoff, pack->filesize - mapoff, outfile);
1260 		} else {
1261 			if (lseek(pack->fd, obj->pack_offset, SEEK_SET) == -1)
1262 				return got_error_from_errno("lseek");
1263 			err = got_inflate_to_file_fd(&obj->size, pack->fd,
1264 			    outfile);
1265 		}
1266 	} else
1267 		err = dump_delta_chain_to_file(&obj->size, &obj->deltas, pack,
1268 		    outfile, base_file, accum_file);
1269 
1270 	return err;
1271 }
1272 
1273 const struct got_error *
1274 got_packfile_extract_object_to_mem(uint8_t **buf, size_t *len,
1275     struct got_object *obj, struct got_pack *pack)
1276 {
1277 	const struct got_error *err = NULL;
1278 
1279 	if ((obj->flags & GOT_OBJ_FLAG_PACKED) == 0)
1280 		return got_error(GOT_ERR_OBJ_NOT_PACKED);
1281 
1282 	if ((obj->flags & GOT_OBJ_FLAG_DELTIFIED) == 0) {
1283 		if (obj->pack_offset >= pack->filesize)
1284 			return got_error(GOT_ERR_PACK_OFFSET);
1285 		if (pack->map) {
1286 			size_t mapoff = (size_t)obj->pack_offset;
1287 			err = got_inflate_to_mem_mmap(buf, len, pack->map,
1288 			    mapoff, pack->filesize - mapoff);
1289 		} else {
1290 			if (lseek(pack->fd, obj->pack_offset, SEEK_SET) == -1)
1291 				return got_error_from_errno("lseek");
1292 			err = got_inflate_to_mem_fd(buf, len, pack->fd);
1293 		}
1294 	} else
1295 		err = dump_delta_chain_to_mem(buf, len, &obj->deltas, pack);
1296 
1297 	return err;
1298 }