archive_read_support_format_zip.c revision 305192
1/*-
2 * Copyright (c) 2004-2013 Tim Kientzle
3 * Copyright (c) 2011-2012,2014 Michihiro NAKAJIMA
4 * Copyright (c) 2013 Konrad Kleine
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include "archive_platform.h"
29__FBSDID("$FreeBSD: stable/10/contrib/libarchive/libarchive/archive_read_support_format_zip.c 305192 2016-09-01 12:01:23Z mm $");
30
31/*
32 * The definitive documentation of the Zip file format is:
33 *   http://www.pkware.com/documents/casestudies/APPNOTE.TXT
34 *
35 * The Info-Zip project has pioneered various extensions to better
36 * support Zip on Unix, including the 0x5455 "UT", 0x5855 "UX", 0x7855
37 * "Ux", and 0x7875 "ux" extensions for time and ownership
38 * information.
39 *
40 * History of this code: The streaming Zip reader was first added to
41 * libarchive in January 2005.  Support for seekable input sources was
42 * added in Nov 2011.  Zip64 support (including a significant code
43 * refactoring) was added in 2014.
44 */
45
46#ifdef HAVE_ERRNO_H
47#include <errno.h>
48#endif
49#ifdef HAVE_STDLIB_H
50#include <stdlib.h>
51#endif
52#ifdef HAVE_ZLIB_H
53#include <zlib.h>
54#endif
55
56#include "archive.h"
57#include "archive_digest_private.h"
58#include "archive_cryptor_private.h"
59#include "archive_endian.h"
60#include "archive_entry.h"
61#include "archive_entry_locale.h"
62#include "archive_hmac_private.h"
63#include "archive_private.h"
64#include "archive_rb.h"
65#include "archive_read_private.h"
66
67#ifndef HAVE_ZLIB_H
68#include "archive_crc32.h"
69#endif
70
71struct zip_entry {
72	struct archive_rb_node	node;
73	struct zip_entry	*next;
74	int64_t			local_header_offset;
75	int64_t			compressed_size;
76	int64_t			uncompressed_size;
77	int64_t			gid;
78	int64_t			uid;
79	struct archive_string	rsrcname;
80	time_t			mtime;
81	time_t			atime;
82	time_t			ctime;
83	uint32_t		crc32;
84	uint16_t		mode;
85	uint16_t		zip_flags; /* From GP Flags Field */
86	unsigned char		compression;
87	unsigned char		system; /* From "version written by" */
88	unsigned char		flags; /* Our extra markers. */
89	unsigned char		decdat;/* Used for Decryption check */
90
91	/* WinZip AES encryption extra field should be available
92	 * when compression is 99. */
93	struct {
94		/* Vendor version: AE-1 - 0x0001, AE-2 - 0x0002 */
95		unsigned	vendor;
96#define AES_VENDOR_AE_1	0x0001
97#define AES_VENDOR_AE_2	0x0002
98		/* AES encryption strength:
99		 * 1 - 128 bits, 2 - 192 bits, 2 - 256 bits. */
100		unsigned	strength;
101		/* Actual compression method. */
102		unsigned char	compression;
103	}			aes_extra;
104};
105
106struct trad_enc_ctx {
107	uint32_t	keys[3];
108};
109
110/* Bits used in zip_flags. */
111#define ZIP_ENCRYPTED	(1 << 0)
112#define ZIP_LENGTH_AT_END	(1 << 3)
113#define ZIP_STRONG_ENCRYPTED	(1 << 6)
114#define ZIP_UTF8_NAME	(1 << 11)
115/* See "7.2 Single Password Symmetric Encryption Method"
116   in http://www.pkware.com/documents/casestudies/APPNOTE.TXT */
117#define ZIP_CENTRAL_DIRECTORY_ENCRYPTED	(1 << 13)
118
119/* Bits used in flags. */
120#define LA_USED_ZIP64	(1 << 0)
121#define LA_FROM_CENTRAL_DIRECTORY (1 << 1)
122
123/*
124 * See "WinZip - AES Encryption Information"
125 *     http://www.winzip.com/aes_info.htm
126 */
127/* Value used in compression method. */
128#define WINZIP_AES_ENCRYPTION	99
129/* Authentication code size. */
130#define AUTH_CODE_SIZE	10
131/**/
132#define MAX_DERIVED_KEY_BUF_SIZE	(AES_MAX_KEY_SIZE * 2 + 2)
133
134struct zip {
135	/* Structural information about the archive. */
136	struct archive_string	format_name;
137	int64_t			central_directory_offset;
138	size_t			central_directory_entries_total;
139	size_t			central_directory_entries_on_this_disk;
140	int			has_encrypted_entries;
141
142	/* List of entries (seekable Zip only) */
143	struct zip_entry	*zip_entries;
144	struct archive_rb_tree	tree;
145	struct archive_rb_tree	tree_rsrc;
146
147	/* Bytes read but not yet consumed via __archive_read_consume() */
148	size_t			unconsumed;
149
150	/* Information about entry we're currently reading. */
151	struct zip_entry	*entry;
152	int64_t			entry_bytes_remaining;
153
154	/* These count the number of bytes actually read for the entry. */
155	int64_t			entry_compressed_bytes_read;
156	int64_t			entry_uncompressed_bytes_read;
157
158	/* Running CRC32 of the decompressed data */
159	unsigned long		entry_crc32;
160	unsigned long		(*crc32func)(unsigned long, const void *,
161				    size_t);
162	char			ignore_crc32;
163
164	/* Flags to mark progress of decompression. */
165	char			decompress_init;
166	char			end_of_entry;
167
168#ifdef HAVE_ZLIB_H
169	unsigned char 		*uncompressed_buffer;
170	size_t 			uncompressed_buffer_size;
171	z_stream		stream;
172	char			stream_valid;
173#endif
174
175	struct archive_string_conv *sconv;
176	struct archive_string_conv *sconv_default;
177	struct archive_string_conv *sconv_utf8;
178	int			init_default_conversion;
179	int			process_mac_extensions;
180
181	char			init_decryption;
182
183	/* Decryption buffer. */
184	/*
185	 * The decrypted data starts at decrypted_ptr and
186	 * extends for decrypted_bytes_remaining.  Decryption
187	 * adds new data to the end of this block, data is returned
188	 * to clients from the beginning.  When the block hits the
189	 * end of decrypted_buffer, it has to be shuffled back to
190	 * the beginning of the buffer.
191	 */
192	unsigned char 		*decrypted_buffer;
193	unsigned char 		*decrypted_ptr;
194	size_t 			decrypted_buffer_size;
195	size_t 			decrypted_bytes_remaining;
196	size_t 			decrypted_unconsumed_bytes;
197
198	/* Traditional PKWARE decryption. */
199	struct trad_enc_ctx	tctx;
200	char			tctx_valid;
201
202	/* WinZip AES decyption. */
203	/* Contexts used for AES decryption. */
204	archive_crypto_ctx	cctx;
205	char			cctx_valid;
206	archive_hmac_sha1_ctx	hctx;
207	char			hctx_valid;
208
209	/* Strong encryption's decryption header information. */
210	unsigned		iv_size;
211	unsigned		alg_id;
212	unsigned		bit_len;
213	unsigned		flags;
214	unsigned		erd_size;
215	unsigned		v_size;
216	unsigned		v_crc32;
217	uint8_t			*iv;
218	uint8_t			*erd;
219	uint8_t			*v_data;
220};
221
222/* Many systems define min or MIN, but not all. */
223#define	zipmin(a,b) ((a) < (b) ? (a) : (b))
224
225/* ------------------------------------------------------------------------ */
226
227/*
228  Traditional PKWARE Decryption functions.
229 */
230
231static void
232trad_enc_update_keys(struct trad_enc_ctx *ctx, uint8_t c)
233{
234	uint8_t t;
235#define CRC32(c, b) (crc32(c ^ 0xffffffffUL, &b, 1) ^ 0xffffffffUL)
236
237	ctx->keys[0] = CRC32(ctx->keys[0], c);
238	ctx->keys[1] = (ctx->keys[1] + (ctx->keys[0] & 0xff)) * 134775813L + 1;
239	t = (ctx->keys[1] >> 24) & 0xff;
240	ctx->keys[2] = CRC32(ctx->keys[2], t);
241#undef CRC32
242}
243
244static uint8_t
245trad_enc_decypt_byte(struct trad_enc_ctx *ctx)
246{
247	unsigned temp = ctx->keys[2] | 2;
248	return (uint8_t)((temp * (temp ^ 1)) >> 8) & 0xff;
249}
250
251static void
252trad_enc_decrypt_update(struct trad_enc_ctx *ctx, const uint8_t *in,
253    size_t in_len, uint8_t *out, size_t out_len)
254{
255	unsigned i, max;
256
257	max = (unsigned)((in_len < out_len)? in_len: out_len);
258
259	for (i = 0; i < max; i++) {
260		uint8_t t = in[i] ^ trad_enc_decypt_byte(ctx);
261		out[i] = t;
262		trad_enc_update_keys(ctx, t);
263	}
264}
265
266static int
267trad_enc_init(struct trad_enc_ctx *ctx, const char *pw, size_t pw_len,
268    const uint8_t *key, size_t key_len, uint8_t *crcchk)
269{
270	uint8_t header[12];
271
272	if (key_len < 12) {
273		*crcchk = 0xff;
274		return -1;
275	}
276
277	ctx->keys[0] = 305419896L;
278	ctx->keys[1] = 591751049L;
279	ctx->keys[2] = 878082192L;
280
281	for (;pw_len; --pw_len)
282		trad_enc_update_keys(ctx, *pw++);
283
284	trad_enc_decrypt_update(ctx, key, 12, header, 12);
285	/* Return the last byte for CRC check. */
286	*crcchk = header[11];
287	return 0;
288}
289
290#if 0
291static void
292crypt_derive_key_sha1(const void *p, int size, unsigned char *key,
293    int key_size)
294{
295#define MD_SIZE 20
296	archive_sha1_ctx ctx;
297	unsigned char md1[MD_SIZE];
298	unsigned char md2[MD_SIZE * 2];
299	unsigned char mkb[64];
300	int i;
301
302	archive_sha1_init(&ctx);
303	archive_sha1_update(&ctx, p, size);
304	archive_sha1_final(&ctx, md1);
305
306	memset(mkb, 0x36, sizeof(mkb));
307	for (i = 0; i < MD_SIZE; i++)
308		mkb[i] ^= md1[i];
309	archive_sha1_init(&ctx);
310	archive_sha1_update(&ctx, mkb, sizeof(mkb));
311	archive_sha1_final(&ctx, md2);
312
313	memset(mkb, 0x5C, sizeof(mkb));
314	for (i = 0; i < MD_SIZE; i++)
315		mkb[i] ^= md1[i];
316	archive_sha1_init(&ctx);
317	archive_sha1_update(&ctx, mkb, sizeof(mkb));
318	archive_sha1_final(&ctx, md2 + MD_SIZE);
319
320	if (key_size > 32)
321		key_size = 32;
322	memcpy(key, md2, key_size);
323#undef MD_SIZE
324}
325#endif
326
327/*
328 * Common code for streaming or seeking modes.
329 *
330 * Includes code to read local file headers, decompress data
331 * from entry bodies, and common API.
332 */
333
334static unsigned long
335real_crc32(unsigned long crc, const void *buff, size_t len)
336{
337	return crc32(crc, buff, (unsigned int)len);
338}
339
340/* Used by "ignorecrc32" option to speed up tests. */
341static unsigned long
342fake_crc32(unsigned long crc, const void *buff, size_t len)
343{
344	(void)crc; /* UNUSED */
345	(void)buff; /* UNUSED */
346	(void)len; /* UNUSED */
347	return 0;
348}
349
350static struct {
351	int id;
352	const char * name;
353} compression_methods[] = {
354	{0, "uncompressed"}, /* The file is stored (no compression) */
355	{1, "shrinking"}, /* The file is Shrunk */
356	{2, "reduced-1"}, /* The file is Reduced with compression factor 1 */
357	{3, "reduced-2"}, /* The file is Reduced with compression factor 2 */
358	{4, "reduced-3"}, /* The file is Reduced with compression factor 3 */
359	{5, "reduced-4"}, /* The file is Reduced with compression factor 4 */
360	{6, "imploded"},  /* The file is Imploded */
361	{7, "reserved"},  /* Reserved for Tokenizing compression algorithm */
362	{8, "deflation"}, /* The file is Deflated */
363	{9, "deflation-64-bit"}, /* Enhanced Deflating using Deflate64(tm) */
364	{10, "ibm-terse"},/* PKWARE Data Compression Library Imploding
365			   * (old IBM TERSE) */
366	{11, "reserved"}, /* Reserved by PKWARE */
367	{12, "bzip"},     /* File is compressed using BZIP2 algorithm */
368	{13, "reserved"}, /* Reserved by PKWARE */
369	{14, "lzma"},     /* LZMA (EFS) */
370	{15, "reserved"}, /* Reserved by PKWARE */
371	{16, "reserved"}, /* Reserved by PKWARE */
372	{17, "reserved"}, /* Reserved by PKWARE */
373	{18, "ibm-terse-new"}, /* File is compressed using IBM TERSE (new) */
374	{19, "ibm-lz777"},/* IBM LZ77 z Architecture (PFS) */
375	{97, "wav-pack"}, /* WavPack compressed data */
376	{98, "ppmd-1"},   /* PPMd version I, Rev 1 */
377	{99, "aes"}       /* WinZip AES encryption  */
378};
379
380static const char *
381compression_name(const int compression)
382{
383	static const int num_compression_methods =
384		sizeof(compression_methods)/sizeof(compression_methods[0]);
385	int i=0;
386
387	while(compression >= 0 && i < num_compression_methods) {
388		if (compression_methods[i].id == compression)
389			return compression_methods[i].name;
390		i++;
391	}
392	return "??";
393}
394
395/* Convert an MSDOS-style date/time into Unix-style time. */
396static time_t
397zip_time(const char *p)
398{
399	int msTime, msDate;
400	struct tm ts;
401
402	msTime = (0xff & (unsigned)p[0]) + 256 * (0xff & (unsigned)p[1]);
403	msDate = (0xff & (unsigned)p[2]) + 256 * (0xff & (unsigned)p[3]);
404
405	memset(&ts, 0, sizeof(ts));
406	ts.tm_year = ((msDate >> 9) & 0x7f) + 80; /* Years since 1900. */
407	ts.tm_mon = ((msDate >> 5) & 0x0f) - 1; /* Month number. */
408	ts.tm_mday = msDate & 0x1f; /* Day of month. */
409	ts.tm_hour = (msTime >> 11) & 0x1f;
410	ts.tm_min = (msTime >> 5) & 0x3f;
411	ts.tm_sec = (msTime << 1) & 0x3e;
412	ts.tm_isdst = -1;
413	return mktime(&ts);
414}
415
416/*
417 * The extra data is stored as a list of
418 *	id1+size1+data1 + id2+size2+data2 ...
419 *  triplets.  id and size are 2 bytes each.
420 */
421static int
422process_extra(struct archive_read *a, const char *p, size_t extra_length, struct zip_entry* zip_entry)
423{
424	unsigned offset = 0;
425
426	if (extra_length == 0) {
427		return ARCHIVE_OK;
428	}
429
430	if (extra_length < 4) {
431		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
432		    "Too-small extra data: Need at least 4 bytes, but only found %d bytes", (int)extra_length);
433		return ARCHIVE_FAILED;
434	}
435	while (offset <= extra_length - 4) {
436		unsigned short headerid = archive_le16dec(p + offset);
437		unsigned short datasize = archive_le16dec(p + offset + 2);
438
439		offset += 4;
440		if (offset + datasize > extra_length) {
441			archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
442			    "Extra data overflow: Need %d bytes but only found %d bytes",
443			    (int)datasize, (int)(extra_length - offset));
444			return ARCHIVE_FAILED;
445		}
446#ifdef DEBUG
447		fprintf(stderr, "Header id 0x%04x, length %d\n",
448		    headerid, datasize);
449#endif
450		switch (headerid) {
451		case 0x0001:
452			/* Zip64 extended information extra field. */
453			zip_entry->flags |= LA_USED_ZIP64;
454			if (zip_entry->uncompressed_size == 0xffffffff) {
455				if (datasize < 8)
456					break;
457				zip_entry->uncompressed_size =
458				    archive_le64dec(p + offset);
459				offset += 8;
460				datasize -= 8;
461			}
462			if (zip_entry->compressed_size == 0xffffffff) {
463				if (datasize < 8)
464					break;
465				zip_entry->compressed_size =
466				    archive_le64dec(p + offset);
467				offset += 8;
468				datasize -= 8;
469			}
470			if (zip_entry->local_header_offset == 0xffffffff) {
471				if (datasize < 8)
472					break;
473				zip_entry->local_header_offset =
474				    archive_le64dec(p + offset);
475				offset += 8;
476				datasize -= 8;
477			}
478			/* archive_le32dec(p + offset) gives disk
479			 * on which file starts, but we don't handle
480			 * multi-volume Zip files. */
481			break;
482#ifdef DEBUG
483		case 0x0017:
484		{
485			/* Strong encryption field. */
486			if (archive_le16dec(p + offset) == 2) {
487				unsigned algId =
488					archive_le16dec(p + offset + 2);
489				unsigned bitLen =
490					archive_le16dec(p + offset + 4);
491				int	 flags =
492					archive_le16dec(p + offset + 6);
493				fprintf(stderr, "algId=0x%04x, bitLen=%u, "
494				    "flgas=%d\n", algId, bitLen,flags);
495			}
496			break;
497		}
498#endif
499		case 0x5455:
500		{
501			/* Extended time field "UT". */
502			int flags = p[offset];
503			offset++;
504			datasize--;
505			/* Flag bits indicate which dates are present. */
506			if (flags & 0x01)
507			{
508#ifdef DEBUG
509				fprintf(stderr, "mtime: %lld -> %d\n",
510				    (long long)zip_entry->mtime,
511				    archive_le32dec(p + offset));
512#endif
513				if (datasize < 4)
514					break;
515				zip_entry->mtime = archive_le32dec(p + offset);
516				offset += 4;
517				datasize -= 4;
518			}
519			if (flags & 0x02)
520			{
521				if (datasize < 4)
522					break;
523				zip_entry->atime = archive_le32dec(p + offset);
524				offset += 4;
525				datasize -= 4;
526			}
527			if (flags & 0x04)
528			{
529				if (datasize < 4)
530					break;
531				zip_entry->ctime = archive_le32dec(p + offset);
532				offset += 4;
533				datasize -= 4;
534			}
535			break;
536		}
537		case 0x5855:
538		{
539			/* Info-ZIP Unix Extra Field (old version) "UX". */
540			if (datasize >= 8) {
541				zip_entry->atime = archive_le32dec(p + offset);
542				zip_entry->mtime =
543				    archive_le32dec(p + offset + 4);
544			}
545			if (datasize >= 12) {
546				zip_entry->uid =
547				    archive_le16dec(p + offset + 8);
548				zip_entry->gid =
549				    archive_le16dec(p + offset + 10);
550			}
551			break;
552		}
553		case 0x6c78:
554		{
555			/* Experimental 'xl' field */
556			/*
557			 * Introduced Dec 2013 to provide a way to
558			 * include external file attributes (and other
559			 * fields that ordinarily appear only in
560			 * central directory) in local file header.
561			 * This provides file type and permission
562			 * information necessary to support full
563			 * streaming extraction.  Currently being
564			 * discussed with other Zip developers
565			 * ... subject to change.
566			 *
567			 * Format:
568			 *  The field starts with a bitmap that specifies
569			 *  which additional fields are included.  The
570			 *  bitmap is variable length and can be extended in
571			 *  the future.
572			 *
573			 *  n bytes - feature bitmap: first byte has low-order
574			 *    7 bits.  If high-order bit is set, a subsequent
575			 *    byte holds the next 7 bits, etc.
576			 *
577			 *  if bitmap & 1, 2 byte "version made by"
578			 *  if bitmap & 2, 2 byte "internal file attributes"
579			 *  if bitmap & 4, 4 byte "external file attributes"
580			 *  if bitmap & 8, 2 byte comment length + n byte comment
581			 */
582			int bitmap, bitmap_last;
583
584			if (datasize < 1)
585				break;
586			bitmap_last = bitmap = 0xff & p[offset];
587			offset += 1;
588			datasize -= 1;
589
590			/* We only support first 7 bits of bitmap; skip rest. */
591			while ((bitmap_last & 0x80) != 0
592			    && datasize >= 1) {
593				bitmap_last = p[offset];
594				offset += 1;
595				datasize -= 1;
596			}
597
598			if (bitmap & 1) {
599				/* 2 byte "version made by" */
600				if (datasize < 2)
601					break;
602				zip_entry->system
603				    = archive_le16dec(p + offset) >> 8;
604				offset += 2;
605				datasize -= 2;
606			}
607			if (bitmap & 2) {
608				/* 2 byte "internal file attributes" */
609				uint32_t internal_attributes;
610				if (datasize < 2)
611					break;
612				internal_attributes
613				    = archive_le16dec(p + offset);
614				/* Not used by libarchive at present. */
615				(void)internal_attributes; /* UNUSED */
616				offset += 2;
617				datasize -= 2;
618			}
619			if (bitmap & 4) {
620				/* 4 byte "external file attributes" */
621				uint32_t external_attributes;
622				if (datasize < 4)
623					break;
624				external_attributes
625				    = archive_le32dec(p + offset);
626				if (zip_entry->system == 3) {
627					zip_entry->mode
628					    = external_attributes >> 16;
629				} else if (zip_entry->system == 0) {
630					// Interpret MSDOS directory bit
631					if (0x10 == (external_attributes & 0x10)) {
632						zip_entry->mode = AE_IFDIR | 0775;
633					} else {
634						zip_entry->mode = AE_IFREG | 0664;
635					}
636					if (0x01 == (external_attributes & 0x01)) {
637						// Read-only bit; strip write permissions
638						zip_entry->mode &= 0555;
639					}
640				} else {
641					zip_entry->mode = 0;
642				}
643				offset += 4;
644				datasize -= 4;
645			}
646			if (bitmap & 8) {
647				/* 2 byte comment length + comment */
648				uint32_t comment_length;
649				if (datasize < 2)
650					break;
651				comment_length
652				    = archive_le16dec(p + offset);
653				offset += 2;
654				datasize -= 2;
655
656				if (datasize < comment_length)
657					break;
658				/* Comment is not supported by libarchive */
659				offset += comment_length;
660				datasize -= comment_length;
661			}
662			break;
663		}
664		case 0x7855:
665			/* Info-ZIP Unix Extra Field (type 2) "Ux". */
666#ifdef DEBUG
667			fprintf(stderr, "uid %d gid %d\n",
668			    archive_le16dec(p + offset),
669			    archive_le16dec(p + offset + 2));
670#endif
671			if (datasize >= 2)
672				zip_entry->uid = archive_le16dec(p + offset);
673			if (datasize >= 4)
674				zip_entry->gid =
675				    archive_le16dec(p + offset + 2);
676			break;
677		case 0x7875:
678		{
679			/* Info-Zip Unix Extra Field (type 3) "ux". */
680			int uidsize = 0, gidsize = 0;
681
682			/* TODO: support arbitrary uidsize/gidsize. */
683			if (datasize >= 1 && p[offset] == 1) {/* version=1 */
684				if (datasize >= 4) {
685					/* get a uid size. */
686					uidsize = 0xff & (int)p[offset+1];
687					if (uidsize == 2)
688						zip_entry->uid =
689						    archive_le16dec(
690						        p + offset + 2);
691					else if (uidsize == 4 && datasize >= 6)
692						zip_entry->uid =
693						    archive_le32dec(
694						        p + offset + 2);
695				}
696				if (datasize >= (2 + uidsize + 3)) {
697					/* get a gid size. */
698					gidsize = 0xff & (int)p[offset+2+uidsize];
699					if (gidsize == 2)
700						zip_entry->gid =
701						    archive_le16dec(
702						        p+offset+2+uidsize+1);
703					else if (gidsize == 4 &&
704					    datasize >= (2 + uidsize + 5))
705						zip_entry->gid =
706						    archive_le32dec(
707						        p+offset+2+uidsize+1);
708				}
709			}
710			break;
711		}
712		case 0x9901:
713			/* WinZIp AES extra data field. */
714			if (p[offset + 2] == 'A' && p[offset + 3] == 'E') {
715				/* Vendor version. */
716				zip_entry->aes_extra.vendor =
717				    archive_le16dec(p + offset);
718				/* AES encryption strength. */
719				zip_entry->aes_extra.strength = p[offset + 4];
720				/* Actual compression method. */
721				zip_entry->aes_extra.compression =
722				    p[offset + 5];
723			}
724			break;
725		default:
726			break;
727		}
728		offset += datasize;
729	}
730	if (offset != extra_length) {
731		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
732		    "Malformed extra data: Consumed %d bytes of %d bytes",
733		    (int)offset, (int)extra_length);
734		return ARCHIVE_FAILED;
735	}
736	return ARCHIVE_OK;
737}
738
739/*
740 * Assumes file pointer is at beginning of local file header.
741 */
742static int
743zip_read_local_file_header(struct archive_read *a, struct archive_entry *entry,
744    struct zip *zip)
745{
746	const char *p;
747	const void *h;
748	const wchar_t *wp;
749	const char *cp;
750	size_t len, filename_length, extra_length;
751	struct archive_string_conv *sconv;
752	struct zip_entry *zip_entry = zip->entry;
753	struct zip_entry zip_entry_central_dir;
754	int ret = ARCHIVE_OK;
755	char version;
756
757	/* Save a copy of the original for consistency checks. */
758	zip_entry_central_dir = *zip_entry;
759
760	zip->decompress_init = 0;
761	zip->end_of_entry = 0;
762	zip->entry_uncompressed_bytes_read = 0;
763	zip->entry_compressed_bytes_read = 0;
764	zip->entry_crc32 = zip->crc32func(0, NULL, 0);
765
766	/* Setup default conversion. */
767	if (zip->sconv == NULL && !zip->init_default_conversion) {
768		zip->sconv_default =
769		    archive_string_default_conversion_for_read(&(a->archive));
770		zip->init_default_conversion = 1;
771	}
772
773	if ((p = __archive_read_ahead(a, 30, NULL)) == NULL) {
774		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
775		    "Truncated ZIP file header");
776		return (ARCHIVE_FATAL);
777	}
778
779	if (memcmp(p, "PK\003\004", 4) != 0) {
780		archive_set_error(&a->archive, -1, "Damaged Zip archive");
781		return ARCHIVE_FATAL;
782	}
783	version = p[4];
784	zip_entry->system = p[5];
785	zip_entry->zip_flags = archive_le16dec(p + 6);
786	if (zip_entry->zip_flags & (ZIP_ENCRYPTED | ZIP_STRONG_ENCRYPTED)) {
787		zip->has_encrypted_entries = 1;
788		archive_entry_set_is_data_encrypted(entry, 1);
789		if (zip_entry->zip_flags & ZIP_CENTRAL_DIRECTORY_ENCRYPTED &&
790			zip_entry->zip_flags & ZIP_ENCRYPTED &&
791			zip_entry->zip_flags & ZIP_STRONG_ENCRYPTED) {
792			archive_entry_set_is_metadata_encrypted(entry, 1);
793			return ARCHIVE_FATAL;
794		}
795	}
796	zip->init_decryption = (zip_entry->zip_flags & ZIP_ENCRYPTED);
797	zip_entry->compression = (char)archive_le16dec(p + 8);
798	zip_entry->mtime = zip_time(p + 10);
799	zip_entry->crc32 = archive_le32dec(p + 14);
800	if (zip_entry->zip_flags & ZIP_LENGTH_AT_END)
801		zip_entry->decdat = p[11];
802	else
803		zip_entry->decdat = p[17];
804	zip_entry->compressed_size = archive_le32dec(p + 18);
805	zip_entry->uncompressed_size = archive_le32dec(p + 22);
806	filename_length = archive_le16dec(p + 26);
807	extra_length = archive_le16dec(p + 28);
808
809	__archive_read_consume(a, 30);
810
811	/* Read the filename. */
812	if ((h = __archive_read_ahead(a, filename_length, NULL)) == NULL) {
813		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
814		    "Truncated ZIP file header");
815		return (ARCHIVE_FATAL);
816	}
817	if (zip_entry->zip_flags & ZIP_UTF8_NAME) {
818		/* The filename is stored to be UTF-8. */
819		if (zip->sconv_utf8 == NULL) {
820			zip->sconv_utf8 =
821			    archive_string_conversion_from_charset(
822				&a->archive, "UTF-8", 1);
823			if (zip->sconv_utf8 == NULL)
824				return (ARCHIVE_FATAL);
825		}
826		sconv = zip->sconv_utf8;
827	} else if (zip->sconv != NULL)
828		sconv = zip->sconv;
829	else
830		sconv = zip->sconv_default;
831
832	if (archive_entry_copy_pathname_l(entry,
833	    h, filename_length, sconv) != 0) {
834		if (errno == ENOMEM) {
835			archive_set_error(&a->archive, ENOMEM,
836			    "Can't allocate memory for Pathname");
837			return (ARCHIVE_FATAL);
838		}
839		archive_set_error(&a->archive,
840		    ARCHIVE_ERRNO_FILE_FORMAT,
841		    "Pathname cannot be converted "
842		    "from %s to current locale.",
843		    archive_string_conversion_charset_name(sconv));
844		ret = ARCHIVE_WARN;
845	}
846	__archive_read_consume(a, filename_length);
847
848	/* Read the extra data. */
849	if ((h = __archive_read_ahead(a, extra_length, NULL)) == NULL) {
850		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
851		    "Truncated ZIP file header");
852		return (ARCHIVE_FATAL);
853	}
854
855	if (ARCHIVE_OK != process_extra(a, h, extra_length, zip_entry)) {
856		return ARCHIVE_FATAL;
857	}
858	__archive_read_consume(a, extra_length);
859
860	/* Work around a bug in Info-Zip: When reading from a pipe, it
861	 * stats the pipe instead of synthesizing a file entry. */
862	if ((zip_entry->mode & AE_IFMT) == AE_IFIFO) {
863		zip_entry->mode &= ~ AE_IFMT;
864		zip_entry->mode |= AE_IFREG;
865	}
866
867	if ((zip_entry->mode & AE_IFMT) == 0) {
868		/* Especially in streaming mode, we can end up
869		   here without having seen proper mode information.
870		   Guess from the filename. */
871		wp = archive_entry_pathname_w(entry);
872		if (wp != NULL) {
873			len = wcslen(wp);
874			if (len > 0 && wp[len - 1] == L'/')
875				zip_entry->mode |= AE_IFDIR;
876			else
877				zip_entry->mode |= AE_IFREG;
878		} else {
879			cp = archive_entry_pathname(entry);
880			len = (cp != NULL)?strlen(cp):0;
881			if (len > 0 && cp[len - 1] == '/')
882				zip_entry->mode |= AE_IFDIR;
883			else
884				zip_entry->mode |= AE_IFREG;
885		}
886		if (zip_entry->mode == AE_IFDIR) {
887			zip_entry->mode |= 0775;
888		} else if (zip_entry->mode == AE_IFREG) {
889			zip_entry->mode |= 0664;
890		}
891	}
892
893	/* Make sure directories end in '/' */
894	if ((zip_entry->mode & AE_IFMT) == AE_IFDIR) {
895		wp = archive_entry_pathname_w(entry);
896		if (wp != NULL) {
897			len = wcslen(wp);
898			if (len > 0 && wp[len - 1] != L'/') {
899				struct archive_wstring s;
900				archive_string_init(&s);
901				archive_wstrcat(&s, wp);
902				archive_wstrappend_wchar(&s, L'/');
903				archive_entry_copy_pathname_w(entry, s.s);
904			}
905		} else {
906			cp = archive_entry_pathname(entry);
907			len = (cp != NULL)?strlen(cp):0;
908			if (len > 0 && cp[len - 1] != '/') {
909				struct archive_string s;
910				archive_string_init(&s);
911				archive_strcat(&s, cp);
912				archive_strappend_char(&s, '/');
913				archive_entry_set_pathname(entry, s.s);
914			}
915		}
916	}
917
918	if (zip_entry->flags & LA_FROM_CENTRAL_DIRECTORY) {
919		/* If this came from the central dir, it's size info
920		 * is definitive, so ignore the length-at-end flag. */
921		zip_entry->zip_flags &= ~ZIP_LENGTH_AT_END;
922		/* If local header is missing a value, use the one from
923		   the central directory.  If both have it, warn about
924		   mismatches. */
925		if (zip_entry->crc32 == 0) {
926			zip_entry->crc32 = zip_entry_central_dir.crc32;
927		} else if (!zip->ignore_crc32
928		    && zip_entry->crc32 != zip_entry_central_dir.crc32) {
929			archive_set_error(&a->archive,
930			    ARCHIVE_ERRNO_FILE_FORMAT,
931			    "Inconsistent CRC32 values");
932			ret = ARCHIVE_WARN;
933		}
934		if (zip_entry->compressed_size == 0) {
935			zip_entry->compressed_size
936			    = zip_entry_central_dir.compressed_size;
937		} else if (zip_entry->compressed_size
938		    != zip_entry_central_dir.compressed_size) {
939			archive_set_error(&a->archive,
940			    ARCHIVE_ERRNO_FILE_FORMAT,
941			    "Inconsistent compressed size: "
942			    "%jd in central directory, %jd in local header",
943			    (intmax_t)zip_entry_central_dir.compressed_size,
944			    (intmax_t)zip_entry->compressed_size);
945			ret = ARCHIVE_WARN;
946		}
947		if (zip_entry->uncompressed_size == 0) {
948			zip_entry->uncompressed_size
949			    = zip_entry_central_dir.uncompressed_size;
950		} else if (zip_entry->uncompressed_size
951		    != zip_entry_central_dir.uncompressed_size) {
952			archive_set_error(&a->archive,
953			    ARCHIVE_ERRNO_FILE_FORMAT,
954			    "Inconsistent uncompressed size: "
955			    "%jd in central directory, %jd in local header",
956			    (intmax_t)zip_entry_central_dir.uncompressed_size,
957			    (intmax_t)zip_entry->uncompressed_size);
958			ret = ARCHIVE_WARN;
959		}
960	}
961
962	/* Populate some additional entry fields: */
963	archive_entry_set_mode(entry, zip_entry->mode);
964	archive_entry_set_uid(entry, zip_entry->uid);
965	archive_entry_set_gid(entry, zip_entry->gid);
966	archive_entry_set_mtime(entry, zip_entry->mtime, 0);
967	archive_entry_set_ctime(entry, zip_entry->ctime, 0);
968	archive_entry_set_atime(entry, zip_entry->atime, 0);
969
970	if ((zip->entry->mode & AE_IFMT) == AE_IFLNK) {
971		size_t linkname_length;
972
973		if (zip_entry->compressed_size > 64 * 1024) {
974			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
975			    "Zip file with oversized link entry");
976			return ARCHIVE_FATAL;
977		}
978
979		linkname_length = (size_t)zip_entry->compressed_size;
980
981		archive_entry_set_size(entry, 0);
982		p = __archive_read_ahead(a, linkname_length, NULL);
983		if (p == NULL) {
984			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
985			    "Truncated Zip file");
986			return ARCHIVE_FATAL;
987		}
988
989		sconv = zip->sconv;
990		if (sconv == NULL && (zip->entry->zip_flags & ZIP_UTF8_NAME))
991			sconv = zip->sconv_utf8;
992		if (sconv == NULL)
993			sconv = zip->sconv_default;
994		if (archive_entry_copy_symlink_l(entry, p, linkname_length,
995		    sconv) != 0) {
996			if (errno != ENOMEM && sconv == zip->sconv_utf8 &&
997			    (zip->entry->zip_flags & ZIP_UTF8_NAME))
998			    archive_entry_copy_symlink_l(entry, p,
999				linkname_length, NULL);
1000			if (errno == ENOMEM) {
1001				archive_set_error(&a->archive, ENOMEM,
1002				    "Can't allocate memory for Symlink");
1003				return (ARCHIVE_FATAL);
1004			}
1005			/*
1006			 * Since there is no character-set regulation for
1007			 * symlink name, do not report the conversion error
1008			 * in an automatic conversion.
1009			 */
1010			if (sconv != zip->sconv_utf8 ||
1011			    (zip->entry->zip_flags & ZIP_UTF8_NAME) == 0) {
1012				archive_set_error(&a->archive,
1013				    ARCHIVE_ERRNO_FILE_FORMAT,
1014				    "Symlink cannot be converted "
1015				    "from %s to current locale.",
1016				    archive_string_conversion_charset_name(
1017					sconv));
1018				ret = ARCHIVE_WARN;
1019			}
1020		}
1021		zip_entry->uncompressed_size = zip_entry->compressed_size = 0;
1022
1023		if (__archive_read_consume(a, linkname_length) < 0) {
1024			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1025			    "Read error skipping symlink target name");
1026			return ARCHIVE_FATAL;
1027		}
1028	} else if (0 == (zip_entry->zip_flags & ZIP_LENGTH_AT_END)
1029	    || zip_entry->uncompressed_size > 0) {
1030		/* Set the size only if it's meaningful. */
1031		archive_entry_set_size(entry, zip_entry->uncompressed_size);
1032	}
1033	zip->entry_bytes_remaining = zip_entry->compressed_size;
1034
1035	/* If there's no body, force read_data() to return EOF immediately. */
1036	if (0 == (zip_entry->zip_flags & ZIP_LENGTH_AT_END)
1037	    && zip->entry_bytes_remaining < 1)
1038		zip->end_of_entry = 1;
1039
1040	/* Set up a more descriptive format name. */
1041	archive_string_sprintf(&zip->format_name, "ZIP %d.%d (%s)",
1042	    version / 10, version % 10,
1043	    compression_name(zip->entry->compression));
1044	a->archive.archive_format_name = zip->format_name.s;
1045
1046	return (ret);
1047}
1048
1049static int
1050check_authentication_code(struct archive_read *a, const void *_p)
1051{
1052	struct zip *zip = (struct zip *)(a->format->data);
1053
1054	/* Check authentication code. */
1055	if (zip->hctx_valid) {
1056		const void *p;
1057		uint8_t hmac[20];
1058		size_t hmac_len = 20;
1059		int cmp;
1060
1061		archive_hmac_sha1_final(&zip->hctx, hmac, &hmac_len);
1062		if (_p == NULL) {
1063			/* Read authentication code. */
1064			p = __archive_read_ahead(a, AUTH_CODE_SIZE, NULL);
1065			if (p == NULL) {
1066				archive_set_error(&a->archive,
1067				    ARCHIVE_ERRNO_FILE_FORMAT,
1068				    "Truncated ZIP file data");
1069				return (ARCHIVE_FATAL);
1070			}
1071		} else {
1072			p = _p;
1073		}
1074		cmp = memcmp(hmac, p, AUTH_CODE_SIZE);
1075		__archive_read_consume(a, AUTH_CODE_SIZE);
1076		if (cmp != 0) {
1077			archive_set_error(&a->archive,
1078			    ARCHIVE_ERRNO_MISC,
1079			    "ZIP bad Authentication code");
1080			return (ARCHIVE_WARN);
1081		}
1082	}
1083	return (ARCHIVE_OK);
1084}
1085
1086/*
1087 * Read "uncompressed" data.  There are three cases:
1088 *  1) We know the size of the data.  This is always true for the
1089 * seeking reader (we've examined the Central Directory already).
1090 *  2) ZIP_LENGTH_AT_END was set, but only the CRC was deferred.
1091 * Info-ZIP seems to do this; we know the size but have to grab
1092 * the CRC from the data descriptor afterwards.
1093 *  3) We're streaming and ZIP_LENGTH_AT_END was specified and
1094 * we have no size information.  In this case, we can do pretty
1095 * well by watching for the data descriptor record.  The data
1096 * descriptor is 16 bytes and includes a computed CRC that should
1097 * provide a strong check.
1098 *
1099 * TODO: Technically, the PK\007\010 signature is optional.
1100 * In the original spec, the data descriptor contained CRC
1101 * and size fields but had no leading signature.  In practice,
1102 * newer writers seem to provide the signature pretty consistently.
1103 *
1104 * For uncompressed data, the PK\007\010 marker seems essential
1105 * to be sure we've actually seen the end of the entry.
1106 *
1107 * Returns ARCHIVE_OK if successful, ARCHIVE_FATAL otherwise, sets
1108 * zip->end_of_entry if it consumes all of the data.
1109 */
1110static int
1111zip_read_data_none(struct archive_read *a, const void **_buff,
1112    size_t *size, int64_t *offset)
1113{
1114	struct zip *zip;
1115	const char *buff;
1116	ssize_t bytes_avail;
1117	int r;
1118
1119	(void)offset; /* UNUSED */
1120
1121	zip = (struct zip *)(a->format->data);
1122
1123	if (zip->entry->zip_flags & ZIP_LENGTH_AT_END) {
1124		const char *p;
1125		ssize_t grabbing_bytes = 24;
1126
1127		if (zip->hctx_valid)
1128			grabbing_bytes += AUTH_CODE_SIZE;
1129		/* Grab at least 24 bytes. */
1130		buff = __archive_read_ahead(a, grabbing_bytes, &bytes_avail);
1131		if (bytes_avail < grabbing_bytes) {
1132			/* Zip archives have end-of-archive markers
1133			   that are longer than this, so a failure to get at
1134			   least 24 bytes really does indicate a truncated
1135			   file. */
1136			archive_set_error(&a->archive,
1137			    ARCHIVE_ERRNO_FILE_FORMAT,
1138			    "Truncated ZIP file data");
1139			return (ARCHIVE_FATAL);
1140		}
1141		/* Check for a complete PK\007\010 signature, followed
1142		 * by the correct 4-byte CRC. */
1143		p = buff;
1144		if (zip->hctx_valid)
1145			p += AUTH_CODE_SIZE;
1146		if (p[0] == 'P' && p[1] == 'K'
1147		    && p[2] == '\007' && p[3] == '\010'
1148		    && (archive_le32dec(p + 4) == zip->entry_crc32
1149			|| zip->ignore_crc32
1150			|| (zip->hctx_valid
1151			 && zip->entry->aes_extra.vendor == AES_VENDOR_AE_2))) {
1152			if (zip->entry->flags & LA_USED_ZIP64) {
1153				zip->entry->crc32 = archive_le32dec(p + 4);
1154				zip->entry->compressed_size =
1155					archive_le64dec(p + 8);
1156				zip->entry->uncompressed_size =
1157					archive_le64dec(p + 16);
1158				zip->unconsumed = 24;
1159			} else {
1160				zip->entry->crc32 = archive_le32dec(p + 4);
1161				zip->entry->compressed_size =
1162					archive_le32dec(p + 8);
1163				zip->entry->uncompressed_size =
1164					archive_le32dec(p + 12);
1165				zip->unconsumed = 16;
1166			}
1167			if (zip->hctx_valid) {
1168				r = check_authentication_code(a, buff);
1169				if (r != ARCHIVE_OK)
1170					return (r);
1171			}
1172			zip->end_of_entry = 1;
1173			return (ARCHIVE_OK);
1174		}
1175		/* If not at EOF, ensure we consume at least one byte. */
1176		++p;
1177
1178		/* Scan forward until we see where a PK\007\010 signature
1179		 * might be. */
1180		/* Return bytes up until that point.  On the next call,
1181		 * the code above will verify the data descriptor. */
1182		while (p < buff + bytes_avail - 4) {
1183			if (p[3] == 'P') { p += 3; }
1184			else if (p[3] == 'K') { p += 2; }
1185			else if (p[3] == '\007') { p += 1; }
1186			else if (p[3] == '\010' && p[2] == '\007'
1187			    && p[1] == 'K' && p[0] == 'P') {
1188				if (zip->hctx_valid)
1189					p -= AUTH_CODE_SIZE;
1190				break;
1191			} else { p += 4; }
1192		}
1193		bytes_avail = p - buff;
1194	} else {
1195		if (zip->entry_bytes_remaining == 0) {
1196			zip->end_of_entry = 1;
1197			if (zip->hctx_valid) {
1198				r = check_authentication_code(a, NULL);
1199				if (r != ARCHIVE_OK)
1200					return (r);
1201			}
1202			return (ARCHIVE_OK);
1203		}
1204		/* Grab a bunch of bytes. */
1205		buff = __archive_read_ahead(a, 1, &bytes_avail);
1206		if (bytes_avail <= 0) {
1207			archive_set_error(&a->archive,
1208			    ARCHIVE_ERRNO_FILE_FORMAT,
1209			    "Truncated ZIP file data");
1210			return (ARCHIVE_FATAL);
1211		}
1212		if (bytes_avail > zip->entry_bytes_remaining)
1213			bytes_avail = (ssize_t)zip->entry_bytes_remaining;
1214	}
1215	if (zip->tctx_valid || zip->cctx_valid) {
1216		size_t dec_size = bytes_avail;
1217
1218		if (dec_size > zip->decrypted_buffer_size)
1219			dec_size = zip->decrypted_buffer_size;
1220		if (zip->tctx_valid) {
1221			trad_enc_decrypt_update(&zip->tctx,
1222			    (const uint8_t *)buff, dec_size,
1223			    zip->decrypted_buffer, dec_size);
1224		} else {
1225			size_t dsize = dec_size;
1226			archive_hmac_sha1_update(&zip->hctx,
1227			    (const uint8_t *)buff, dec_size);
1228			archive_decrypto_aes_ctr_update(&zip->cctx,
1229			    (const uint8_t *)buff, dec_size,
1230			    zip->decrypted_buffer, &dsize);
1231		}
1232		bytes_avail = dec_size;
1233		buff = (const char *)zip->decrypted_buffer;
1234	}
1235	*size = bytes_avail;
1236	zip->entry_bytes_remaining -= bytes_avail;
1237	zip->entry_uncompressed_bytes_read += bytes_avail;
1238	zip->entry_compressed_bytes_read += bytes_avail;
1239	zip->unconsumed += bytes_avail;
1240	*_buff = buff;
1241	return (ARCHIVE_OK);
1242}
1243
1244#ifdef HAVE_ZLIB_H
1245static int
1246zip_deflate_init(struct archive_read *a, struct zip *zip)
1247{
1248	int r;
1249
1250	/* If we haven't yet read any data, initialize the decompressor. */
1251	if (!zip->decompress_init) {
1252		if (zip->stream_valid)
1253			r = inflateReset(&zip->stream);
1254		else
1255			r = inflateInit2(&zip->stream,
1256			    -15 /* Don't check for zlib header */);
1257		if (r != Z_OK) {
1258			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1259			    "Can't initialize ZIP decompression.");
1260			return (ARCHIVE_FATAL);
1261		}
1262		/* Stream structure has been set up. */
1263		zip->stream_valid = 1;
1264		/* We've initialized decompression for this stream. */
1265		zip->decompress_init = 1;
1266	}
1267	return (ARCHIVE_OK);
1268}
1269
1270static int
1271zip_read_data_deflate(struct archive_read *a, const void **buff,
1272    size_t *size, int64_t *offset)
1273{
1274	struct zip *zip;
1275	ssize_t bytes_avail;
1276	const void *compressed_buff, *sp;
1277	int r;
1278
1279	(void)offset; /* UNUSED */
1280
1281	zip = (struct zip *)(a->format->data);
1282
1283	/* If the buffer hasn't been allocated, allocate it now. */
1284	if (zip->uncompressed_buffer == NULL) {
1285		zip->uncompressed_buffer_size = 256 * 1024;
1286		zip->uncompressed_buffer
1287		    = (unsigned char *)malloc(zip->uncompressed_buffer_size);
1288		if (zip->uncompressed_buffer == NULL) {
1289			archive_set_error(&a->archive, ENOMEM,
1290			    "No memory for ZIP decompression");
1291			return (ARCHIVE_FATAL);
1292		}
1293	}
1294
1295	r = zip_deflate_init(a, zip);
1296	if (r != ARCHIVE_OK)
1297		return (r);
1298
1299	/*
1300	 * Note: '1' here is a performance optimization.
1301	 * Recall that the decompression layer returns a count of
1302	 * available bytes; asking for more than that forces the
1303	 * decompressor to combine reads by copying data.
1304	 */
1305	compressed_buff = sp = __archive_read_ahead(a, 1, &bytes_avail);
1306	if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END)
1307	    && bytes_avail > zip->entry_bytes_remaining) {
1308		bytes_avail = (ssize_t)zip->entry_bytes_remaining;
1309	}
1310	if (bytes_avail < 0) {
1311		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1312		    "Truncated ZIP file body");
1313		return (ARCHIVE_FATAL);
1314	}
1315
1316	if (zip->tctx_valid || zip->cctx_valid) {
1317		if (zip->decrypted_bytes_remaining < (size_t)bytes_avail) {
1318			size_t buff_remaining =
1319			    (zip->decrypted_buffer + zip->decrypted_buffer_size)
1320			    - (zip->decrypted_ptr + zip->decrypted_bytes_remaining);
1321
1322			if (buff_remaining > (size_t)bytes_avail)
1323				buff_remaining = (size_t)bytes_avail;
1324
1325			if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END) &&
1326			      zip->entry_bytes_remaining > 0) {
1327				if ((int64_t)(zip->decrypted_bytes_remaining
1328				    + buff_remaining)
1329				      > zip->entry_bytes_remaining) {
1330					if (zip->entry_bytes_remaining <
1331					      (int64_t)zip->decrypted_bytes_remaining)
1332						buff_remaining = 0;
1333					else
1334						buff_remaining =
1335						    (size_t)zip->entry_bytes_remaining
1336						      - zip->decrypted_bytes_remaining;
1337				}
1338			}
1339			if (buff_remaining > 0) {
1340				if (zip->tctx_valid) {
1341					trad_enc_decrypt_update(&zip->tctx,
1342					    compressed_buff, buff_remaining,
1343					    zip->decrypted_ptr
1344					      + zip->decrypted_bytes_remaining,
1345					    buff_remaining);
1346				} else {
1347					size_t dsize = buff_remaining;
1348					archive_decrypto_aes_ctr_update(
1349					    &zip->cctx,
1350					    compressed_buff, buff_remaining,
1351					    zip->decrypted_ptr
1352					      + zip->decrypted_bytes_remaining,
1353					    &dsize);
1354				}
1355				zip->decrypted_bytes_remaining += buff_remaining;
1356			}
1357		}
1358		bytes_avail = zip->decrypted_bytes_remaining;
1359		compressed_buff = (const char *)zip->decrypted_ptr;
1360	}
1361
1362	/*
1363	 * A bug in zlib.h: stream.next_in should be marked 'const'
1364	 * but isn't (the library never alters data through the
1365	 * next_in pointer, only reads it).  The result: this ugly
1366	 * cast to remove 'const'.
1367	 */
1368	zip->stream.next_in = (Bytef *)(uintptr_t)(const void *)compressed_buff;
1369	zip->stream.avail_in = (uInt)bytes_avail;
1370	zip->stream.total_in = 0;
1371	zip->stream.next_out = zip->uncompressed_buffer;
1372	zip->stream.avail_out = (uInt)zip->uncompressed_buffer_size;
1373	zip->stream.total_out = 0;
1374
1375	r = inflate(&zip->stream, 0);
1376	switch (r) {
1377	case Z_OK:
1378		break;
1379	case Z_STREAM_END:
1380		zip->end_of_entry = 1;
1381		break;
1382	case Z_MEM_ERROR:
1383		archive_set_error(&a->archive, ENOMEM,
1384		    "Out of memory for ZIP decompression");
1385		return (ARCHIVE_FATAL);
1386	default:
1387		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1388		    "ZIP decompression failed (%d)", r);
1389		return (ARCHIVE_FATAL);
1390	}
1391
1392	/* Consume as much as the compressor actually used. */
1393	bytes_avail = zip->stream.total_in;
1394	if (zip->tctx_valid || zip->cctx_valid) {
1395		zip->decrypted_bytes_remaining -= bytes_avail;
1396		if (zip->decrypted_bytes_remaining == 0)
1397			zip->decrypted_ptr = zip->decrypted_buffer;
1398		else
1399			zip->decrypted_ptr += bytes_avail;
1400	}
1401	/* Calculate compressed data as much as we used.*/
1402	if (zip->hctx_valid)
1403		archive_hmac_sha1_update(&zip->hctx, sp, bytes_avail);
1404	__archive_read_consume(a, bytes_avail);
1405	zip->entry_bytes_remaining -= bytes_avail;
1406	zip->entry_compressed_bytes_read += bytes_avail;
1407
1408	*size = zip->stream.total_out;
1409	zip->entry_uncompressed_bytes_read += zip->stream.total_out;
1410	*buff = zip->uncompressed_buffer;
1411
1412	if (zip->end_of_entry && zip->hctx_valid) {
1413		r = check_authentication_code(a, NULL);
1414		if (r != ARCHIVE_OK)
1415			return (r);
1416	}
1417
1418	if (zip->end_of_entry && (zip->entry->zip_flags & ZIP_LENGTH_AT_END)) {
1419		const char *p;
1420
1421		if (NULL == (p = __archive_read_ahead(a, 24, NULL))) {
1422			archive_set_error(&a->archive,
1423			    ARCHIVE_ERRNO_FILE_FORMAT,
1424			    "Truncated ZIP end-of-file record");
1425			return (ARCHIVE_FATAL);
1426		}
1427		/* Consume the optional PK\007\010 marker. */
1428		if (p[0] == 'P' && p[1] == 'K' &&
1429		    p[2] == '\007' && p[3] == '\010') {
1430			p += 4;
1431			zip->unconsumed = 4;
1432		}
1433		if (zip->entry->flags & LA_USED_ZIP64) {
1434			zip->entry->crc32 = archive_le32dec(p);
1435			zip->entry->compressed_size = archive_le64dec(p + 4);
1436			zip->entry->uncompressed_size = archive_le64dec(p + 12);
1437			zip->unconsumed += 20;
1438		} else {
1439			zip->entry->crc32 = archive_le32dec(p);
1440			zip->entry->compressed_size = archive_le32dec(p + 4);
1441			zip->entry->uncompressed_size = archive_le32dec(p + 8);
1442			zip->unconsumed += 12;
1443		}
1444	}
1445
1446	return (ARCHIVE_OK);
1447}
1448#endif
1449
1450static int
1451read_decryption_header(struct archive_read *a)
1452{
1453	struct zip *zip = (struct zip *)(a->format->data);
1454	const char *p;
1455	unsigned int remaining_size;
1456	unsigned int ts;
1457
1458	/*
1459	 * Read an initialization vector data field.
1460	 */
1461	p = __archive_read_ahead(a, 2, NULL);
1462	if (p == NULL)
1463		goto truncated;
1464	ts = zip->iv_size;
1465	zip->iv_size = archive_le16dec(p);
1466	__archive_read_consume(a, 2);
1467	if (ts < zip->iv_size) {
1468		free(zip->iv);
1469		zip->iv = NULL;
1470	}
1471	p = __archive_read_ahead(a, zip->iv_size, NULL);
1472	if (p == NULL)
1473		goto truncated;
1474	if (zip->iv == NULL) {
1475		zip->iv = malloc(zip->iv_size);
1476		if (zip->iv == NULL)
1477			goto nomem;
1478	}
1479	memcpy(zip->iv, p, zip->iv_size);
1480	__archive_read_consume(a, zip->iv_size);
1481
1482	/*
1483	 * Read a size of remaining decryption header field.
1484	 */
1485	p = __archive_read_ahead(a, 14, NULL);
1486	if (p == NULL)
1487		goto truncated;
1488	remaining_size = archive_le32dec(p);
1489	if (remaining_size < 16 || remaining_size > (1 << 18))
1490		goto corrupted;
1491
1492	/* Check if format version is supported. */
1493	if (archive_le16dec(p+4) != 3) {
1494		archive_set_error(&a->archive,
1495		    ARCHIVE_ERRNO_FILE_FORMAT,
1496		    "Unsupported encryption format version: %u",
1497		    archive_le16dec(p+4));
1498		return (ARCHIVE_FAILED);
1499	}
1500
1501	/*
1502	 * Read an encryption algorithm field.
1503	 */
1504	zip->alg_id = archive_le16dec(p+6);
1505	switch (zip->alg_id) {
1506	case 0x6601:/* DES */
1507	case 0x6602:/* RC2 */
1508	case 0x6603:/* 3DES 168 */
1509	case 0x6609:/* 3DES 112 */
1510	case 0x660E:/* AES 128 */
1511	case 0x660F:/* AES 192 */
1512	case 0x6610:/* AES 256 */
1513	case 0x6702:/* RC2 (version >= 5.2) */
1514	case 0x6720:/* Blowfish */
1515	case 0x6721:/* Twofish */
1516	case 0x6801:/* RC4 */
1517		/* Suuported encryption algorithm. */
1518		break;
1519	default:
1520		archive_set_error(&a->archive,
1521		    ARCHIVE_ERRNO_FILE_FORMAT,
1522		    "Unknown encryption algorithm: %u", zip->alg_id);
1523		return (ARCHIVE_FAILED);
1524	}
1525
1526	/*
1527	 * Read a bit length field.
1528	 */
1529	zip->bit_len = archive_le16dec(p+8);
1530
1531	/*
1532	 * Read a flags field.
1533	 */
1534	zip->flags = archive_le16dec(p+10);
1535	switch (zip->flags & 0xf000) {
1536	case 0x0001: /* Password is required to decrypt. */
1537	case 0x0002: /* Certificates only. */
1538	case 0x0003: /* Password or certificate required to decrypt. */
1539		break;
1540	default:
1541		archive_set_error(&a->archive,
1542		    ARCHIVE_ERRNO_FILE_FORMAT,
1543		    "Unknown encryption flag: %u", zip->flags);
1544		return (ARCHIVE_FAILED);
1545	}
1546	if ((zip->flags & 0xf000) == 0 ||
1547	    (zip->flags & 0xf000) == 0x4000) {
1548		archive_set_error(&a->archive,
1549		    ARCHIVE_ERRNO_FILE_FORMAT,
1550		    "Unknown encryption flag: %u", zip->flags);
1551		return (ARCHIVE_FAILED);
1552	}
1553
1554	/*
1555	 * Read an encrypted random data field.
1556	 */
1557	ts = zip->erd_size;
1558	zip->erd_size = archive_le16dec(p+12);
1559	__archive_read_consume(a, 14);
1560	if ((zip->erd_size & 0xf) != 0 ||
1561	    (zip->erd_size + 16) > remaining_size ||
1562	    (zip->erd_size + 16) < zip->erd_size)
1563		goto corrupted;
1564
1565	if (ts < zip->erd_size) {
1566		free(zip->erd);
1567		zip->erd = NULL;
1568	}
1569	p = __archive_read_ahead(a, zip->erd_size, NULL);
1570	if (p == NULL)
1571		goto truncated;
1572	if (zip->erd == NULL) {
1573		zip->erd = malloc(zip->erd_size);
1574		if (zip->erd == NULL)
1575			goto nomem;
1576	}
1577	memcpy(zip->erd, p, zip->erd_size);
1578	__archive_read_consume(a, zip->erd_size);
1579
1580	/*
1581	 * Read a reserved data field.
1582	 */
1583	p = __archive_read_ahead(a, 4, NULL);
1584	if (p == NULL)
1585		goto truncated;
1586	/* Reserved data size should be zero. */
1587	if (archive_le32dec(p) != 0)
1588		goto corrupted;
1589	__archive_read_consume(a, 4);
1590
1591	/*
1592	 * Read a password validation data field.
1593	 */
1594	p = __archive_read_ahead(a, 2, NULL);
1595	if (p == NULL)
1596		goto truncated;
1597	ts = zip->v_size;
1598	zip->v_size = archive_le16dec(p);
1599	__archive_read_consume(a, 2);
1600	if ((zip->v_size & 0x0f) != 0 ||
1601	    (zip->erd_size + zip->v_size + 16) > remaining_size ||
1602	    (zip->erd_size + zip->v_size + 16) < (zip->erd_size + zip->v_size))
1603		goto corrupted;
1604	if (ts < zip->v_size) {
1605		free(zip->v_data);
1606		zip->v_data = NULL;
1607	}
1608	p = __archive_read_ahead(a, zip->v_size, NULL);
1609	if (p == NULL)
1610		goto truncated;
1611	if (zip->v_data == NULL) {
1612		zip->v_data = malloc(zip->v_size);
1613		if (zip->v_data == NULL)
1614			goto nomem;
1615	}
1616	memcpy(zip->v_data, p, zip->v_size);
1617	__archive_read_consume(a, zip->v_size);
1618
1619	p = __archive_read_ahead(a, 4, NULL);
1620	if (p == NULL)
1621		goto truncated;
1622	zip->v_crc32 = archive_le32dec(p);
1623	__archive_read_consume(a, 4);
1624
1625	/*return (ARCHIVE_OK);
1626	 * This is not fully implemnted yet.*/
1627	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1628	    "Encrypted file is unsupported");
1629	return (ARCHIVE_FAILED);
1630truncated:
1631	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1632	    "Truncated ZIP file data");
1633	return (ARCHIVE_FATAL);
1634corrupted:
1635	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1636	    "Corrupted ZIP file data");
1637	return (ARCHIVE_FATAL);
1638nomem:
1639	archive_set_error(&a->archive, ENOMEM,
1640	    "No memory for ZIP decryption");
1641	return (ARCHIVE_FATAL);
1642}
1643
1644static int
1645zip_alloc_decryption_buffer(struct archive_read *a)
1646{
1647	struct zip *zip = (struct zip *)(a->format->data);
1648	size_t bs = 256 * 1024;
1649
1650	if (zip->decrypted_buffer == NULL) {
1651		zip->decrypted_buffer_size = bs;
1652		zip->decrypted_buffer = malloc(bs);
1653		if (zip->decrypted_buffer == NULL) {
1654			archive_set_error(&a->archive, ENOMEM,
1655			    "No memory for ZIP decryption");
1656			return (ARCHIVE_FATAL);
1657		}
1658	}
1659	zip->decrypted_ptr = zip->decrypted_buffer;
1660	return (ARCHIVE_OK);
1661}
1662
1663static int
1664init_traditional_PKWARE_decryption(struct archive_read *a)
1665{
1666	struct zip *zip = (struct zip *)(a->format->data);
1667	const void *p;
1668	int retry;
1669	int r;
1670
1671	if (zip->tctx_valid)
1672		return (ARCHIVE_OK);
1673
1674	/*
1675	   Read the 12 bytes encryption header stored at
1676	   the start of the data area.
1677	 */
1678#define ENC_HEADER_SIZE	12
1679	if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END)
1680	    && zip->entry_bytes_remaining < ENC_HEADER_SIZE) {
1681		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1682		    "Truncated Zip encrypted body: only %jd bytes available",
1683		    (intmax_t)zip->entry_bytes_remaining);
1684		return (ARCHIVE_FATAL);
1685	}
1686
1687	p = __archive_read_ahead(a, ENC_HEADER_SIZE, NULL);
1688	if (p == NULL) {
1689		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1690		    "Truncated ZIP file data");
1691		return (ARCHIVE_FATAL);
1692	}
1693
1694	for (retry = 0;; retry++) {
1695		const char *passphrase;
1696		uint8_t crcchk;
1697
1698		passphrase = __archive_read_next_passphrase(a);
1699		if (passphrase == NULL) {
1700			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1701			    (retry > 0)?
1702				"Incorrect passphrase":
1703				"Passphrase required for this entry");
1704			return (ARCHIVE_FAILED);
1705		}
1706
1707		/*
1708		 * Initialize ctx for Traditional PKWARE Decyption.
1709		 */
1710		r = trad_enc_init(&zip->tctx, passphrase, strlen(passphrase),
1711			p, ENC_HEADER_SIZE, &crcchk);
1712		if (r == 0 && crcchk == zip->entry->decdat)
1713			break;/* The passphrase is OK. */
1714		if (retry > 10000) {
1715			/* Avoid infinity loop. */
1716			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1717			    "Too many incorrect passphrases");
1718			return (ARCHIVE_FAILED);
1719		}
1720	}
1721
1722	__archive_read_consume(a, ENC_HEADER_SIZE);
1723	zip->tctx_valid = 1;
1724	if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END)) {
1725	    zip->entry_bytes_remaining -= ENC_HEADER_SIZE;
1726	}
1727	/*zip->entry_uncompressed_bytes_read += ENC_HEADER_SIZE;*/
1728	zip->entry_compressed_bytes_read += ENC_HEADER_SIZE;
1729	zip->decrypted_bytes_remaining = 0;
1730
1731	return (zip_alloc_decryption_buffer(a));
1732#undef ENC_HEADER_SIZE
1733}
1734
1735static int
1736init_WinZip_AES_decryption(struct archive_read *a)
1737{
1738	struct zip *zip = (struct zip *)(a->format->data);
1739	const void *p;
1740	const uint8_t *pv;
1741	size_t key_len, salt_len;
1742	uint8_t derived_key[MAX_DERIVED_KEY_BUF_SIZE];
1743	int retry;
1744	int r;
1745
1746	if (zip->cctx_valid || zip->hctx_valid)
1747		return (ARCHIVE_OK);
1748
1749	switch (zip->entry->aes_extra.strength) {
1750	case 1: salt_len = 8;  key_len = 16; break;
1751	case 2: salt_len = 12; key_len = 24; break;
1752	case 3: salt_len = 16; key_len = 32; break;
1753	default: goto corrupted;
1754	}
1755	p = __archive_read_ahead(a, salt_len + 2, NULL);
1756	if (p == NULL)
1757		goto truncated;
1758
1759	for (retry = 0;; retry++) {
1760		const char *passphrase;
1761
1762		passphrase = __archive_read_next_passphrase(a);
1763		if (passphrase == NULL) {
1764			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1765			    (retry > 0)?
1766				"Incorrect passphrase":
1767				"Passphrase required for this entry");
1768			return (ARCHIVE_FAILED);
1769		}
1770		memset(derived_key, 0, sizeof(derived_key));
1771		r = archive_pbkdf2_sha1(passphrase, strlen(passphrase),
1772		    p, salt_len, 1000, derived_key, key_len * 2 + 2);
1773		if (r != 0) {
1774			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1775			    "Decryption is unsupported due to lack of "
1776			    "crypto library");
1777			return (ARCHIVE_FAILED);
1778		}
1779
1780		/* Check password verification value. */
1781		pv = ((const uint8_t *)p) + salt_len;
1782		if (derived_key[key_len * 2] == pv[0] &&
1783		    derived_key[key_len * 2 + 1] == pv[1])
1784			break;/* The passphrase is OK. */
1785		if (retry > 10000) {
1786			/* Avoid infinity loop. */
1787			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1788			    "Too many incorrect passphrases");
1789			return (ARCHIVE_FAILED);
1790		}
1791	}
1792
1793	r = archive_decrypto_aes_ctr_init(&zip->cctx, derived_key, key_len);
1794	if (r != 0) {
1795		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1796		    "Decryption is unsupported due to lack of crypto library");
1797		return (ARCHIVE_FAILED);
1798	}
1799	r = archive_hmac_sha1_init(&zip->hctx, derived_key + key_len, key_len);
1800	if (r != 0) {
1801		archive_decrypto_aes_ctr_release(&zip->cctx);
1802		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1803		    "Failed to initialize HMAC-SHA1");
1804		return (ARCHIVE_FAILED);
1805	}
1806	zip->cctx_valid = zip->hctx_valid = 1;
1807	__archive_read_consume(a, salt_len + 2);
1808	zip->entry_bytes_remaining -= salt_len + 2 + AUTH_CODE_SIZE;
1809	if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END)
1810	    && zip->entry_bytes_remaining < 0)
1811		goto corrupted;
1812	zip->entry_compressed_bytes_read += salt_len + 2 + AUTH_CODE_SIZE;
1813	zip->decrypted_bytes_remaining = 0;
1814
1815	zip->entry->compression = zip->entry->aes_extra.compression;
1816	return (zip_alloc_decryption_buffer(a));
1817
1818truncated:
1819	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1820	    "Truncated ZIP file data");
1821	return (ARCHIVE_FATAL);
1822corrupted:
1823	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1824	    "Corrupted ZIP file data");
1825	return (ARCHIVE_FATAL);
1826}
1827
1828static int
1829archive_read_format_zip_read_data(struct archive_read *a,
1830    const void **buff, size_t *size, int64_t *offset)
1831{
1832	int r;
1833	struct zip *zip = (struct zip *)(a->format->data);
1834
1835	if (zip->has_encrypted_entries ==
1836			ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW) {
1837		zip->has_encrypted_entries = 0;
1838	}
1839
1840	*offset = zip->entry_uncompressed_bytes_read;
1841	*size = 0;
1842	*buff = NULL;
1843
1844	/* If we hit end-of-entry last time, return ARCHIVE_EOF. */
1845	if (zip->end_of_entry)
1846		return (ARCHIVE_EOF);
1847
1848	/* Return EOF immediately if this is a non-regular file. */
1849	if (AE_IFREG != (zip->entry->mode & AE_IFMT))
1850		return (ARCHIVE_EOF);
1851
1852	__archive_read_consume(a, zip->unconsumed);
1853	zip->unconsumed = 0;
1854
1855	if (zip->init_decryption) {
1856		zip->has_encrypted_entries = 1;
1857		if (zip->entry->zip_flags & ZIP_STRONG_ENCRYPTED)
1858			r = read_decryption_header(a);
1859		else if (zip->entry->compression == WINZIP_AES_ENCRYPTION)
1860			r = init_WinZip_AES_decryption(a);
1861		else
1862			r = init_traditional_PKWARE_decryption(a);
1863		if (r != ARCHIVE_OK)
1864			return (r);
1865		zip->init_decryption = 0;
1866	}
1867
1868	switch(zip->entry->compression) {
1869	case 0:  /* No compression. */
1870		r =  zip_read_data_none(a, buff, size, offset);
1871		break;
1872#ifdef HAVE_ZLIB_H
1873	case 8: /* Deflate compression. */
1874		r =  zip_read_data_deflate(a, buff, size, offset);
1875		break;
1876#endif
1877	default: /* Unsupported compression. */
1878		/* Return a warning. */
1879		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1880		    "Unsupported ZIP compression method (%s)",
1881		    compression_name(zip->entry->compression));
1882		/* We can't decompress this entry, but we will
1883		 * be able to skip() it and try the next entry. */
1884		return (ARCHIVE_FAILED);
1885		break;
1886	}
1887	if (r != ARCHIVE_OK)
1888		return (r);
1889	/* Update checksum */
1890	if (*size)
1891		zip->entry_crc32 = zip->crc32func(zip->entry_crc32, *buff,
1892		    (unsigned)*size);
1893	/* If we hit the end, swallow any end-of-data marker. */
1894	if (zip->end_of_entry) {
1895		/* Check file size, CRC against these values. */
1896		if (zip->entry->compressed_size !=
1897		    zip->entry_compressed_bytes_read) {
1898			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1899			    "ZIP compressed data is wrong size "
1900			    "(read %jd, expected %jd)",
1901			    (intmax_t)zip->entry_compressed_bytes_read,
1902			    (intmax_t)zip->entry->compressed_size);
1903			return (ARCHIVE_WARN);
1904		}
1905		/* Size field only stores the lower 32 bits of the actual
1906		 * size. */
1907		if ((zip->entry->uncompressed_size & UINT32_MAX)
1908		    != (zip->entry_uncompressed_bytes_read & UINT32_MAX)) {
1909			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1910			    "ZIP uncompressed data is wrong size "
1911			    "(read %jd, expected %jd)\n",
1912			    (intmax_t)zip->entry_uncompressed_bytes_read,
1913			    (intmax_t)zip->entry->uncompressed_size);
1914			return (ARCHIVE_WARN);
1915		}
1916		/* Check computed CRC against header */
1917		if ((!zip->hctx_valid ||
1918		      zip->entry->aes_extra.vendor != AES_VENDOR_AE_2) &&
1919		   zip->entry->crc32 != zip->entry_crc32
1920		    && !zip->ignore_crc32) {
1921			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1922			    "ZIP bad CRC: 0x%lx should be 0x%lx",
1923			    (unsigned long)zip->entry_crc32,
1924			    (unsigned long)zip->entry->crc32);
1925			return (ARCHIVE_WARN);
1926		}
1927	}
1928
1929	return (ARCHIVE_OK);
1930}
1931
1932static int
1933archive_read_format_zip_cleanup(struct archive_read *a)
1934{
1935	struct zip *zip;
1936	struct zip_entry *zip_entry, *next_zip_entry;
1937
1938	zip = (struct zip *)(a->format->data);
1939#ifdef HAVE_ZLIB_H
1940	if (zip->stream_valid)
1941		inflateEnd(&zip->stream);
1942	free(zip->uncompressed_buffer);
1943#endif
1944	if (zip->zip_entries) {
1945		zip_entry = zip->zip_entries;
1946		while (zip_entry != NULL) {
1947			next_zip_entry = zip_entry->next;
1948			archive_string_free(&zip_entry->rsrcname);
1949			free(zip_entry);
1950			zip_entry = next_zip_entry;
1951		}
1952	}
1953	free(zip->decrypted_buffer);
1954	if (zip->cctx_valid)
1955		archive_decrypto_aes_ctr_release(&zip->cctx);
1956	if (zip->hctx_valid)
1957		archive_hmac_sha1_cleanup(&zip->hctx);
1958	free(zip->iv);
1959	free(zip->erd);
1960	free(zip->v_data);
1961	archive_string_free(&zip->format_name);
1962	free(zip);
1963	(a->format->data) = NULL;
1964	return (ARCHIVE_OK);
1965}
1966
1967static int
1968archive_read_format_zip_has_encrypted_entries(struct archive_read *_a)
1969{
1970	if (_a && _a->format) {
1971		struct zip * zip = (struct zip *)_a->format->data;
1972		if (zip) {
1973			return zip->has_encrypted_entries;
1974		}
1975	}
1976	return ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW;
1977}
1978
1979static int
1980archive_read_format_zip_options(struct archive_read *a,
1981    const char *key, const char *val)
1982{
1983	struct zip *zip;
1984	int ret = ARCHIVE_FAILED;
1985
1986	zip = (struct zip *)(a->format->data);
1987	if (strcmp(key, "compat-2x")  == 0) {
1988		/* Handle filenames as libarchive 2.x */
1989		zip->init_default_conversion = (val != NULL) ? 1 : 0;
1990		return (ARCHIVE_OK);
1991	} else if (strcmp(key, "hdrcharset")  == 0) {
1992		if (val == NULL || val[0] == 0)
1993			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1994			    "zip: hdrcharset option needs a character-set name"
1995			);
1996		else {
1997			zip->sconv = archive_string_conversion_from_charset(
1998			    &a->archive, val, 0);
1999			if (zip->sconv != NULL) {
2000				if (strcmp(val, "UTF-8") == 0)
2001					zip->sconv_utf8 = zip->sconv;
2002				ret = ARCHIVE_OK;
2003			} else
2004				ret = ARCHIVE_FATAL;
2005		}
2006		return (ret);
2007	} else if (strcmp(key, "ignorecrc32") == 0) {
2008		/* Mostly useful for testing. */
2009		if (val == NULL || val[0] == 0) {
2010			zip->crc32func = real_crc32;
2011			zip->ignore_crc32 = 0;
2012		} else {
2013			zip->crc32func = fake_crc32;
2014			zip->ignore_crc32 = 1;
2015		}
2016		return (ARCHIVE_OK);
2017	} else if (strcmp(key, "mac-ext") == 0) {
2018		zip->process_mac_extensions = (val != NULL && val[0] != 0);
2019		return (ARCHIVE_OK);
2020	}
2021
2022	/* Note: The "warn" return is just to inform the options
2023	 * supervisor that we didn't handle it.  It will generate
2024	 * a suitable error if no one used this option. */
2025	return (ARCHIVE_WARN);
2026}
2027
2028int
2029archive_read_support_format_zip(struct archive *a)
2030{
2031	int r;
2032	r = archive_read_support_format_zip_streamable(a);
2033	if (r != ARCHIVE_OK)
2034		return r;
2035	return (archive_read_support_format_zip_seekable(a));
2036}
2037
2038/* ------------------------------------------------------------------------ */
2039
2040/*
2041 * Streaming-mode support
2042 */
2043
2044
2045static int
2046archive_read_support_format_zip_capabilities_streamable(struct archive_read * a)
2047{
2048	(void)a; /* UNUSED */
2049	return (ARCHIVE_READ_FORMAT_CAPS_ENCRYPT_DATA |
2050		ARCHIVE_READ_FORMAT_CAPS_ENCRYPT_METADATA);
2051}
2052
2053static int
2054archive_read_format_zip_streamable_bid(struct archive_read *a, int best_bid)
2055{
2056	const char *p;
2057
2058	(void)best_bid; /* UNUSED */
2059
2060	if ((p = __archive_read_ahead(a, 4, NULL)) == NULL)
2061		return (-1);
2062
2063	/*
2064	 * Bid of 29 here comes from:
2065	 *  + 16 bits for "PK",
2066	 *  + next 16-bit field has 6 options so contributes
2067	 *    about 16 - log_2(6) ~= 16 - 2.6 ~= 13 bits
2068	 *
2069	 * So we've effectively verified ~29 total bits of check data.
2070	 */
2071	if (p[0] == 'P' && p[1] == 'K') {
2072		if ((p[2] == '\001' && p[3] == '\002')
2073		    || (p[2] == '\003' && p[3] == '\004')
2074		    || (p[2] == '\005' && p[3] == '\006')
2075		    || (p[2] == '\006' && p[3] == '\006')
2076		    || (p[2] == '\007' && p[3] == '\010')
2077		    || (p[2] == '0' && p[3] == '0'))
2078			return (29);
2079	}
2080
2081	/* TODO: It's worth looking ahead a little bit for a valid
2082	 * PK signature.  In particular, that would make it possible
2083	 * to read some UUEncoded SFX files or SFX files coming from
2084	 * a network socket. */
2085
2086	return (0);
2087}
2088
2089static int
2090archive_read_format_zip_streamable_read_header(struct archive_read *a,
2091    struct archive_entry *entry)
2092{
2093	struct zip *zip;
2094
2095	a->archive.archive_format = ARCHIVE_FORMAT_ZIP;
2096	if (a->archive.archive_format_name == NULL)
2097		a->archive.archive_format_name = "ZIP";
2098
2099	zip = (struct zip *)(a->format->data);
2100
2101	/*
2102	 * It should be sufficient to call archive_read_next_header() for
2103	 * a reader to determine if an entry is encrypted or not. If the
2104	 * encryption of an entry is only detectable when calling
2105	 * archive_read_data(), so be it. We'll do the same check there
2106	 * as well.
2107	 */
2108	if (zip->has_encrypted_entries ==
2109			ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW)
2110		zip->has_encrypted_entries = 0;
2111
2112	/* Make sure we have a zip_entry structure to use. */
2113	if (zip->zip_entries == NULL) {
2114		zip->zip_entries = malloc(sizeof(struct zip_entry));
2115		if (zip->zip_entries == NULL) {
2116			archive_set_error(&a->archive, ENOMEM,
2117			    "Out  of memory");
2118			return ARCHIVE_FATAL;
2119		}
2120	}
2121	zip->entry = zip->zip_entries;
2122	memset(zip->entry, 0, sizeof(struct zip_entry));
2123
2124	if (zip->cctx_valid)
2125		archive_decrypto_aes_ctr_release(&zip->cctx);
2126	if (zip->hctx_valid)
2127		archive_hmac_sha1_cleanup(&zip->hctx);
2128	zip->tctx_valid = zip->cctx_valid = zip->hctx_valid = 0;
2129	__archive_read_reset_passphrase(a);
2130
2131	/* Search ahead for the next local file header. */
2132	__archive_read_consume(a, zip->unconsumed);
2133	zip->unconsumed = 0;
2134	for (;;) {
2135		int64_t skipped = 0;
2136		const char *p, *end;
2137		ssize_t bytes;
2138
2139		p = __archive_read_ahead(a, 4, &bytes);
2140		if (p == NULL)
2141			return (ARCHIVE_FATAL);
2142		end = p + bytes;
2143
2144		while (p + 4 <= end) {
2145			if (p[0] == 'P' && p[1] == 'K') {
2146				if (p[2] == '\003' && p[3] == '\004') {
2147					/* Regular file entry. */
2148					__archive_read_consume(a, skipped);
2149					return zip_read_local_file_header(a,
2150					    entry, zip);
2151				}
2152
2153                              /*
2154                               * TODO: We cannot restore permissions
2155                               * based only on the local file headers.
2156                               * Consider scanning the central
2157                               * directory and returning additional
2158                               * entries for at least directories.
2159                               * This would allow us to properly set
2160                               * directory permissions.
2161			       *
2162			       * This won't help us fix symlinks
2163			       * and may not help with regular file
2164			       * permissions, either.  <sigh>
2165                               */
2166                              if (p[2] == '\001' && p[3] == '\002') {
2167                                      return (ARCHIVE_EOF);
2168                              }
2169
2170                              /* End of central directory?  Must be an
2171                               * empty archive. */
2172                              if ((p[2] == '\005' && p[3] == '\006')
2173                                  || (p[2] == '\006' && p[3] == '\006'))
2174                                      return (ARCHIVE_EOF);
2175			}
2176			++p;
2177			++skipped;
2178		}
2179		__archive_read_consume(a, skipped);
2180	}
2181}
2182
2183static int
2184archive_read_format_zip_read_data_skip_streamable(struct archive_read *a)
2185{
2186	struct zip *zip;
2187	int64_t bytes_skipped;
2188
2189	zip = (struct zip *)(a->format->data);
2190	bytes_skipped = __archive_read_consume(a, zip->unconsumed);
2191	zip->unconsumed = 0;
2192	if (bytes_skipped < 0)
2193		return (ARCHIVE_FATAL);
2194
2195	/* If we've already read to end of data, we're done. */
2196	if (zip->end_of_entry)
2197		return (ARCHIVE_OK);
2198
2199	/* So we know we're streaming... */
2200	if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END)
2201	    || zip->entry->compressed_size > 0) {
2202		/* We know the compressed length, so we can just skip. */
2203		bytes_skipped = __archive_read_consume(a,
2204					zip->entry_bytes_remaining);
2205		if (bytes_skipped < 0)
2206			return (ARCHIVE_FATAL);
2207		return (ARCHIVE_OK);
2208	}
2209
2210	if (zip->init_decryption) {
2211		int r;
2212
2213		zip->has_encrypted_entries = 1;
2214		if (zip->entry->zip_flags & ZIP_STRONG_ENCRYPTED)
2215			r = read_decryption_header(a);
2216		else if (zip->entry->compression == WINZIP_AES_ENCRYPTION)
2217			r = init_WinZip_AES_decryption(a);
2218		else
2219			r = init_traditional_PKWARE_decryption(a);
2220		if (r != ARCHIVE_OK)
2221			return (r);
2222		zip->init_decryption = 0;
2223	}
2224
2225	/* We're streaming and we don't know the length. */
2226	/* If the body is compressed and we know the format, we can
2227	 * find an exact end-of-entry by decompressing it. */
2228	switch (zip->entry->compression) {
2229#ifdef HAVE_ZLIB_H
2230	case 8: /* Deflate compression. */
2231		while (!zip->end_of_entry) {
2232			int64_t offset = 0;
2233			const void *buff = NULL;
2234			size_t size = 0;
2235			int r;
2236			r =  zip_read_data_deflate(a, &buff, &size, &offset);
2237			if (r != ARCHIVE_OK)
2238				return (r);
2239		}
2240		return ARCHIVE_OK;
2241#endif
2242	default: /* Uncompressed or unknown. */
2243		/* Scan for a PK\007\010 signature. */
2244		for (;;) {
2245			const char *p, *buff;
2246			ssize_t bytes_avail;
2247			buff = __archive_read_ahead(a, 16, &bytes_avail);
2248			if (bytes_avail < 16) {
2249				archive_set_error(&a->archive,
2250				    ARCHIVE_ERRNO_FILE_FORMAT,
2251				    "Truncated ZIP file data");
2252				return (ARCHIVE_FATAL);
2253			}
2254			p = buff;
2255			while (p <= buff + bytes_avail - 16) {
2256				if (p[3] == 'P') { p += 3; }
2257				else if (p[3] == 'K') { p += 2; }
2258				else if (p[3] == '\007') { p += 1; }
2259				else if (p[3] == '\010' && p[2] == '\007'
2260				    && p[1] == 'K' && p[0] == 'P') {
2261					if (zip->entry->flags & LA_USED_ZIP64)
2262						__archive_read_consume(a,
2263						    p - buff + 24);
2264					else
2265						__archive_read_consume(a,
2266						    p - buff + 16);
2267					return ARCHIVE_OK;
2268				} else { p += 4; }
2269			}
2270			__archive_read_consume(a, p - buff);
2271		}
2272	}
2273}
2274
2275int
2276archive_read_support_format_zip_streamable(struct archive *_a)
2277{
2278	struct archive_read *a = (struct archive_read *)_a;
2279	struct zip *zip;
2280	int r;
2281
2282	archive_check_magic(_a, ARCHIVE_READ_MAGIC,
2283	    ARCHIVE_STATE_NEW, "archive_read_support_format_zip");
2284
2285	zip = (struct zip *)calloc(1, sizeof(*zip));
2286	if (zip == NULL) {
2287		archive_set_error(&a->archive, ENOMEM,
2288		    "Can't allocate zip data");
2289		return (ARCHIVE_FATAL);
2290	}
2291
2292	/* Streamable reader doesn't support mac extensions. */
2293	zip->process_mac_extensions = 0;
2294
2295	/*
2296	 * Until enough data has been read, we cannot tell about
2297	 * any encrypted entries yet.
2298	 */
2299	zip->has_encrypted_entries = ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW;
2300	zip->crc32func = real_crc32;
2301
2302	r = __archive_read_register_format(a,
2303	    zip,
2304	    "zip",
2305	    archive_read_format_zip_streamable_bid,
2306	    archive_read_format_zip_options,
2307	    archive_read_format_zip_streamable_read_header,
2308	    archive_read_format_zip_read_data,
2309	    archive_read_format_zip_read_data_skip_streamable,
2310	    NULL,
2311	    archive_read_format_zip_cleanup,
2312	    archive_read_support_format_zip_capabilities_streamable,
2313	    archive_read_format_zip_has_encrypted_entries);
2314
2315	if (r != ARCHIVE_OK)
2316		free(zip);
2317	return (ARCHIVE_OK);
2318}
2319
2320/* ------------------------------------------------------------------------ */
2321
2322/*
2323 * Seeking-mode support
2324 */
2325
2326static int
2327archive_read_support_format_zip_capabilities_seekable(struct archive_read * a)
2328{
2329	(void)a; /* UNUSED */
2330	return (ARCHIVE_READ_FORMAT_CAPS_ENCRYPT_DATA |
2331		ARCHIVE_READ_FORMAT_CAPS_ENCRYPT_METADATA);
2332}
2333
2334/*
2335 * TODO: This is a performance sink because it forces the read core to
2336 * drop buffered data from the start of file, which will then have to
2337 * be re-read again if this bidder loses.
2338 *
2339 * We workaround this a little by passing in the best bid so far so
2340 * that later bidders can do nothing if they know they'll never
2341 * outbid.  But we can certainly do better...
2342 */
2343static int
2344read_eocd(struct zip *zip, const char *p, int64_t current_offset)
2345{
2346	/* Sanity-check the EOCD we've found. */
2347
2348	/* This must be the first volume. */
2349	if (archive_le16dec(p + 4) != 0)
2350		return 0;
2351	/* Central directory must be on this volume. */
2352	if (archive_le16dec(p + 4) != archive_le16dec(p + 6))
2353		return 0;
2354	/* All central directory entries must be on this volume. */
2355	if (archive_le16dec(p + 10) != archive_le16dec(p + 8))
2356		return 0;
2357	/* Central directory can't extend beyond start of EOCD record. */
2358	if (archive_le32dec(p + 16) + archive_le32dec(p + 12)
2359	    > current_offset)
2360		return 0;
2361
2362	/* Save the central directory location for later use. */
2363	zip->central_directory_offset = archive_le32dec(p + 16);
2364
2365	/* This is just a tiny bit higher than the maximum
2366	   returned by the streaming Zip bidder.  This ensures
2367	   that the more accurate seeking Zip parser wins
2368	   whenever seek is available. */
2369	return 32;
2370}
2371
2372/*
2373 * Examine Zip64 EOCD locator:  If it's valid, store the information
2374 * from it.
2375 */
2376static void
2377read_zip64_eocd(struct archive_read *a, struct zip *zip, const char *p)
2378{
2379	int64_t eocd64_offset;
2380	int64_t eocd64_size;
2381
2382	/* Sanity-check the locator record. */
2383
2384	/* Central dir must be on first volume. */
2385	if (archive_le32dec(p + 4) != 0)
2386		return;
2387	/* Must be only a single volume. */
2388	if (archive_le32dec(p + 16) != 1)
2389		return;
2390
2391	/* Find the Zip64 EOCD record. */
2392	eocd64_offset = archive_le64dec(p + 8);
2393	if (__archive_read_seek(a, eocd64_offset, SEEK_SET) < 0)
2394		return;
2395	if ((p = __archive_read_ahead(a, 56, NULL)) == NULL)
2396		return;
2397	/* Make sure we can read all of it. */
2398	eocd64_size = archive_le64dec(p + 4) + 12;
2399	if (eocd64_size < 56 || eocd64_size > 16384)
2400		return;
2401	if ((p = __archive_read_ahead(a, (size_t)eocd64_size, NULL)) == NULL)
2402		return;
2403
2404	/* Sanity-check the EOCD64 */
2405	if (archive_le32dec(p + 16) != 0) /* Must be disk #0 */
2406		return;
2407	if (archive_le32dec(p + 20) != 0) /* CD must be on disk #0 */
2408		return;
2409	/* CD can't be split. */
2410	if (archive_le64dec(p + 24) != archive_le64dec(p + 32))
2411		return;
2412
2413	/* Save the central directory offset for later use. */
2414	zip->central_directory_offset = archive_le64dec(p + 48);
2415}
2416
2417static int
2418archive_read_format_zip_seekable_bid(struct archive_read *a, int best_bid)
2419{
2420	struct zip *zip = (struct zip *)a->format->data;
2421	int64_t file_size, current_offset;
2422	const char *p;
2423	int i, tail;
2424
2425	/* If someone has already bid more than 32, then avoid
2426	   trashing the look-ahead buffers with a seek. */
2427	if (best_bid > 32)
2428		return (-1);
2429
2430	file_size = __archive_read_seek(a, 0, SEEK_END);
2431	if (file_size <= 0)
2432		return 0;
2433
2434	/* Search last 16k of file for end-of-central-directory
2435	 * record (which starts with PK\005\006) */
2436	tail = (int)zipmin(1024 * 16, file_size);
2437	current_offset = __archive_read_seek(a, -tail, SEEK_END);
2438	if (current_offset < 0)
2439		return 0;
2440	if ((p = __archive_read_ahead(a, (size_t)tail, NULL)) == NULL)
2441		return 0;
2442	/* Boyer-Moore search backwards from the end, since we want
2443	 * to match the last EOCD in the file (there can be more than
2444	 * one if there is an uncompressed Zip archive as a member
2445	 * within this Zip archive). */
2446	for (i = tail - 22; i > 0;) {
2447		switch (p[i]) {
2448		case 'P':
2449			if (memcmp(p + i, "PK\005\006", 4) == 0) {
2450				int ret = read_eocd(zip, p + i,
2451				    current_offset + i);
2452				if (ret > 0) {
2453					/* Zip64 EOCD locator precedes
2454					 * regular EOCD if present. */
2455					if (i >= 20
2456					    && memcmp(p + i - 20, "PK\006\007", 4) == 0) {
2457						read_zip64_eocd(a, zip, p + i - 20);
2458					}
2459					return (ret);
2460				}
2461			}
2462			i -= 4;
2463			break;
2464		case 'K': i -= 1; break;
2465		case 005: i -= 2; break;
2466		case 006: i -= 3; break;
2467		default: i -= 4; break;
2468		}
2469	}
2470	return 0;
2471}
2472
2473/* The red-black trees are only used in seeking mode to manage
2474 * the in-memory copy of the central directory. */
2475
2476static int
2477cmp_node(const struct archive_rb_node *n1, const struct archive_rb_node *n2)
2478{
2479	const struct zip_entry *e1 = (const struct zip_entry *)n1;
2480	const struct zip_entry *e2 = (const struct zip_entry *)n2;
2481
2482	if (e1->local_header_offset > e2->local_header_offset)
2483		return -1;
2484	if (e1->local_header_offset < e2->local_header_offset)
2485		return 1;
2486	return 0;
2487}
2488
2489static int
2490cmp_key(const struct archive_rb_node *n, const void *key)
2491{
2492	/* This function won't be called */
2493	(void)n; /* UNUSED */
2494	(void)key; /* UNUSED */
2495	return 1;
2496}
2497
2498static const struct archive_rb_tree_ops rb_ops = {
2499	&cmp_node, &cmp_key
2500};
2501
2502static int
2503rsrc_cmp_node(const struct archive_rb_node *n1,
2504    const struct archive_rb_node *n2)
2505{
2506	const struct zip_entry *e1 = (const struct zip_entry *)n1;
2507	const struct zip_entry *e2 = (const struct zip_entry *)n2;
2508
2509	return (strcmp(e2->rsrcname.s, e1->rsrcname.s));
2510}
2511
2512static int
2513rsrc_cmp_key(const struct archive_rb_node *n, const void *key)
2514{
2515	const struct zip_entry *e = (const struct zip_entry *)n;
2516	return (strcmp((const char *)key, e->rsrcname.s));
2517}
2518
2519static const struct archive_rb_tree_ops rb_rsrc_ops = {
2520	&rsrc_cmp_node, &rsrc_cmp_key
2521};
2522
2523static const char *
2524rsrc_basename(const char *name, size_t name_length)
2525{
2526	const char *s, *r;
2527
2528	r = s = name;
2529	for (;;) {
2530		s = memchr(s, '/', name_length - (s - name));
2531		if (s == NULL)
2532			break;
2533		r = ++s;
2534	}
2535	return (r);
2536}
2537
2538static void
2539expose_parent_dirs(struct zip *zip, const char *name, size_t name_length)
2540{
2541	struct archive_string str;
2542	struct zip_entry *dir;
2543	char *s;
2544
2545	archive_string_init(&str);
2546	archive_strncpy(&str, name, name_length);
2547	for (;;) {
2548		s = strrchr(str.s, '/');
2549		if (s == NULL)
2550			break;
2551		*s = '\0';
2552		/* Transfer the parent directory from zip->tree_rsrc RB
2553		 * tree to zip->tree RB tree to expose. */
2554		dir = (struct zip_entry *)
2555		    __archive_rb_tree_find_node(&zip->tree_rsrc, str.s);
2556		if (dir == NULL)
2557			break;
2558		__archive_rb_tree_remove_node(&zip->tree_rsrc, &dir->node);
2559		archive_string_free(&dir->rsrcname);
2560		__archive_rb_tree_insert_node(&zip->tree, &dir->node);
2561	}
2562	archive_string_free(&str);
2563}
2564
2565static int
2566slurp_central_directory(struct archive_read *a, struct zip *zip)
2567{
2568	ssize_t i;
2569	unsigned found;
2570	int64_t correction;
2571	ssize_t bytes_avail;
2572	const char *p;
2573
2574	/*
2575	 * Find the start of the central directory.  The end-of-CD
2576	 * record has our starting point, but there are lots of
2577	 * Zip archives which have had other data prepended to the
2578	 * file, which makes the recorded offsets all too small.
2579	 * So we search forward from the specified offset until we
2580	 * find the real start of the central directory.  Then we
2581	 * know the correction we need to apply to account for leading
2582	 * padding.
2583	 */
2584	if (__archive_read_seek(a, zip->central_directory_offset, SEEK_SET) < 0)
2585		return ARCHIVE_FATAL;
2586
2587	found = 0;
2588	while (!found) {
2589		if ((p = __archive_read_ahead(a, 20, &bytes_avail)) == NULL)
2590			return ARCHIVE_FATAL;
2591		for (found = 0, i = 0; !found && i < bytes_avail - 4;) {
2592			switch (p[i + 3]) {
2593			case 'P': i += 3; break;
2594			case 'K': i += 2; break;
2595			case 001: i += 1; break;
2596			case 002:
2597				if (memcmp(p + i, "PK\001\002", 4) == 0) {
2598					p += i;
2599					found = 1;
2600				} else
2601					i += 4;
2602				break;
2603			case 005: i += 1; break;
2604			case 006:
2605				if (memcmp(p + i, "PK\005\006", 4) == 0) {
2606					p += i;
2607					found = 1;
2608				} else if (memcmp(p + i, "PK\006\006", 4) == 0) {
2609					p += i;
2610					found = 1;
2611				} else
2612					i += 1;
2613				break;
2614			default: i += 4; break;
2615			}
2616		}
2617		__archive_read_consume(a, i);
2618	}
2619	correction = archive_filter_bytes(&a->archive, 0)
2620			- zip->central_directory_offset;
2621
2622	__archive_rb_tree_init(&zip->tree, &rb_ops);
2623	__archive_rb_tree_init(&zip->tree_rsrc, &rb_rsrc_ops);
2624
2625	zip->central_directory_entries_total = 0;
2626	while (1) {
2627		struct zip_entry *zip_entry;
2628		size_t filename_length, extra_length, comment_length;
2629		uint32_t external_attributes;
2630		const char *name, *r;
2631
2632		if ((p = __archive_read_ahead(a, 4, NULL)) == NULL)
2633			return ARCHIVE_FATAL;
2634		if (memcmp(p, "PK\006\006", 4) == 0
2635		    || memcmp(p, "PK\005\006", 4) == 0) {
2636			break;
2637		} else if (memcmp(p, "PK\001\002", 4) != 0) {
2638			archive_set_error(&a->archive,
2639			    -1, "Invalid central directory signature");
2640			return ARCHIVE_FATAL;
2641		}
2642		if ((p = __archive_read_ahead(a, 46, NULL)) == NULL)
2643			return ARCHIVE_FATAL;
2644
2645		zip_entry = calloc(1, sizeof(struct zip_entry));
2646		zip_entry->next = zip->zip_entries;
2647		zip_entry->flags |= LA_FROM_CENTRAL_DIRECTORY;
2648		zip->zip_entries = zip_entry;
2649		zip->central_directory_entries_total++;
2650
2651		/* version = p[4]; */
2652		zip_entry->system = p[5];
2653		/* version_required = archive_le16dec(p + 6); */
2654		zip_entry->zip_flags = archive_le16dec(p + 8);
2655		if (zip_entry->zip_flags
2656		      & (ZIP_ENCRYPTED | ZIP_STRONG_ENCRYPTED)){
2657			zip->has_encrypted_entries = 1;
2658		}
2659		zip_entry->compression = (char)archive_le16dec(p + 10);
2660		zip_entry->mtime = zip_time(p + 12);
2661		zip_entry->crc32 = archive_le32dec(p + 16);
2662		if (zip_entry->zip_flags & ZIP_LENGTH_AT_END)
2663			zip_entry->decdat = p[13];
2664		else
2665			zip_entry->decdat = p[19];
2666		zip_entry->compressed_size = archive_le32dec(p + 20);
2667		zip_entry->uncompressed_size = archive_le32dec(p + 24);
2668		filename_length = archive_le16dec(p + 28);
2669		extra_length = archive_le16dec(p + 30);
2670		comment_length = archive_le16dec(p + 32);
2671		/* disk_start = archive_le16dec(p + 34); */ /* Better be zero. */
2672		/* internal_attributes = archive_le16dec(p + 36); */ /* text bit */
2673		external_attributes = archive_le32dec(p + 38);
2674		zip_entry->local_header_offset =
2675		    archive_le32dec(p + 42) + correction;
2676
2677		/* If we can't guess the mode, leave it zero here;
2678		   when we read the local file header we might get
2679		   more information. */
2680		if (zip_entry->system == 3) {
2681			zip_entry->mode = external_attributes >> 16;
2682		} else if (zip_entry->system == 0) {
2683			// Interpret MSDOS directory bit
2684			if (0x10 == (external_attributes & 0x10)) {
2685				zip_entry->mode = AE_IFDIR | 0775;
2686			} else {
2687				zip_entry->mode = AE_IFREG | 0664;
2688			}
2689			if (0x01 == (external_attributes & 0x01)) {
2690				// Read-only bit; strip write permissions
2691				zip_entry->mode &= 0555;
2692			}
2693		} else {
2694			zip_entry->mode = 0;
2695		}
2696
2697		/* We're done with the regular data; get the filename and
2698		 * extra data. */
2699		__archive_read_consume(a, 46);
2700		p = __archive_read_ahead(a, filename_length + extra_length,
2701			NULL);
2702		if (p == NULL) {
2703			archive_set_error(&a->archive,
2704			    ARCHIVE_ERRNO_FILE_FORMAT,
2705			    "Truncated ZIP file header");
2706			return ARCHIVE_FATAL;
2707		}
2708		if (ARCHIVE_OK != process_extra(a, p + filename_length, extra_length, zip_entry)) {
2709			return ARCHIVE_FATAL;
2710		}
2711
2712		/*
2713		 * Mac resource fork files are stored under the
2714		 * "__MACOSX/" directory, so we should check if
2715		 * it is.
2716		 */
2717		if (!zip->process_mac_extensions) {
2718			/* Treat every entry as a regular entry. */
2719			__archive_rb_tree_insert_node(&zip->tree,
2720			    &zip_entry->node);
2721		} else {
2722			name = p;
2723			r = rsrc_basename(name, filename_length);
2724			if (filename_length >= 9 &&
2725			    strncmp("__MACOSX/", name, 9) == 0) {
2726				/* If this file is not a resource fork nor
2727				 * a directory. We should treat it as a non
2728				 * resource fork file to expose it. */
2729				if (name[filename_length-1] != '/' &&
2730				    (r - name < 3 || r[0] != '.' || r[1] != '_')) {
2731					__archive_rb_tree_insert_node(
2732					    &zip->tree, &zip_entry->node);
2733					/* Expose its parent directories. */
2734					expose_parent_dirs(zip, name,
2735					    filename_length);
2736				} else {
2737					/* This file is a resource fork file or
2738					 * a directory. */
2739					archive_strncpy(&(zip_entry->rsrcname),
2740					     name, filename_length);
2741					__archive_rb_tree_insert_node(
2742					    &zip->tree_rsrc, &zip_entry->node);
2743				}
2744			} else {
2745				/* Generate resource fork name to find its
2746				 * resource file at zip->tree_rsrc. */
2747				archive_strcpy(&(zip_entry->rsrcname),
2748				    "__MACOSX/");
2749				archive_strncat(&(zip_entry->rsrcname),
2750				    name, r - name);
2751				archive_strcat(&(zip_entry->rsrcname), "._");
2752				archive_strncat(&(zip_entry->rsrcname),
2753				    name + (r - name),
2754				    filename_length - (r - name));
2755				/* Register an entry to RB tree to sort it by
2756				 * file offset. */
2757				__archive_rb_tree_insert_node(&zip->tree,
2758				    &zip_entry->node);
2759			}
2760		}
2761
2762		/* Skip the comment too ... */
2763		__archive_read_consume(a,
2764		    filename_length + extra_length + comment_length);
2765	}
2766
2767	return ARCHIVE_OK;
2768}
2769
2770static ssize_t
2771zip_get_local_file_header_size(struct archive_read *a, size_t extra)
2772{
2773	const char *p;
2774	ssize_t filename_length, extra_length;
2775
2776	if ((p = __archive_read_ahead(a, extra + 30, NULL)) == NULL) {
2777		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2778		    "Truncated ZIP file header");
2779		return (ARCHIVE_WARN);
2780	}
2781	p += extra;
2782
2783	if (memcmp(p, "PK\003\004", 4) != 0) {
2784		archive_set_error(&a->archive, -1, "Damaged Zip archive");
2785		return ARCHIVE_WARN;
2786	}
2787	filename_length = archive_le16dec(p + 26);
2788	extra_length = archive_le16dec(p + 28);
2789
2790	return (30 + filename_length + extra_length);
2791}
2792
2793static int
2794zip_read_mac_metadata(struct archive_read *a, struct archive_entry *entry,
2795    struct zip_entry *rsrc)
2796{
2797	struct zip *zip = (struct zip *)a->format->data;
2798	unsigned char *metadata, *mp;
2799	int64_t offset = archive_filter_bytes(&a->archive, 0);
2800	size_t remaining_bytes, metadata_bytes;
2801	ssize_t hsize;
2802	int ret = ARCHIVE_OK, eof;
2803
2804	switch(rsrc->compression) {
2805	case 0:  /* No compression. */
2806		if (rsrc->uncompressed_size != rsrc->compressed_size) {
2807			archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2808			    "Malformed OS X metadata entry: inconsistent size");
2809			return (ARCHIVE_FATAL);
2810		}
2811#ifdef HAVE_ZLIB_H
2812	case 8: /* Deflate compression. */
2813#endif
2814		break;
2815	default: /* Unsupported compression. */
2816		/* Return a warning. */
2817		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2818		    "Unsupported ZIP compression method (%s)",
2819		    compression_name(rsrc->compression));
2820		/* We can't decompress this entry, but we will
2821		 * be able to skip() it and try the next entry. */
2822		return (ARCHIVE_WARN);
2823	}
2824
2825	if (rsrc->uncompressed_size > (4 * 1024 * 1024)) {
2826		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2827		    "Mac metadata is too large: %jd > 4M bytes",
2828		    (intmax_t)rsrc->uncompressed_size);
2829		return (ARCHIVE_WARN);
2830	}
2831	if (rsrc->compressed_size > (4 * 1024 * 1024)) {
2832		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2833		    "Mac metadata is too large: %jd > 4M bytes",
2834		    (intmax_t)rsrc->compressed_size);
2835		return (ARCHIVE_WARN);
2836	}
2837
2838	metadata = malloc((size_t)rsrc->uncompressed_size);
2839	if (metadata == NULL) {
2840		archive_set_error(&a->archive, ENOMEM,
2841		    "Can't allocate memory for Mac metadata");
2842		return (ARCHIVE_FATAL);
2843	}
2844
2845	if (offset < rsrc->local_header_offset)
2846		__archive_read_consume(a, rsrc->local_header_offset - offset);
2847	else if (offset != rsrc->local_header_offset) {
2848		__archive_read_seek(a, rsrc->local_header_offset, SEEK_SET);
2849	}
2850
2851	hsize = zip_get_local_file_header_size(a, 0);
2852	__archive_read_consume(a, hsize);
2853
2854	remaining_bytes = (size_t)rsrc->compressed_size;
2855	metadata_bytes = (size_t)rsrc->uncompressed_size;
2856	mp = metadata;
2857	eof = 0;
2858	while (!eof && remaining_bytes) {
2859		const unsigned char *p;
2860		ssize_t bytes_avail;
2861		size_t bytes_used;
2862
2863		p = __archive_read_ahead(a, 1, &bytes_avail);
2864		if (p == NULL) {
2865			archive_set_error(&a->archive,
2866			    ARCHIVE_ERRNO_FILE_FORMAT,
2867			    "Truncated ZIP file header");
2868			ret = ARCHIVE_WARN;
2869			goto exit_mac_metadata;
2870		}
2871		if ((size_t)bytes_avail > remaining_bytes)
2872			bytes_avail = remaining_bytes;
2873		switch(rsrc->compression) {
2874		case 0:  /* No compression. */
2875			if ((size_t)bytes_avail > metadata_bytes)
2876				bytes_avail = metadata_bytes;
2877			memcpy(mp, p, bytes_avail);
2878			bytes_used = (size_t)bytes_avail;
2879			metadata_bytes -= bytes_used;
2880			mp += bytes_used;
2881			if (metadata_bytes == 0)
2882				eof = 1;
2883			break;
2884#ifdef HAVE_ZLIB_H
2885		case 8: /* Deflate compression. */
2886		{
2887			int r;
2888
2889			ret = zip_deflate_init(a, zip);
2890			if (ret != ARCHIVE_OK)
2891				goto exit_mac_metadata;
2892			zip->stream.next_in =
2893			    (Bytef *)(uintptr_t)(const void *)p;
2894			zip->stream.avail_in = (uInt)bytes_avail;
2895			zip->stream.total_in = 0;
2896			zip->stream.next_out = mp;
2897			zip->stream.avail_out = (uInt)metadata_bytes;
2898			zip->stream.total_out = 0;
2899
2900			r = inflate(&zip->stream, 0);
2901			switch (r) {
2902			case Z_OK:
2903				break;
2904			case Z_STREAM_END:
2905				eof = 1;
2906				break;
2907			case Z_MEM_ERROR:
2908				archive_set_error(&a->archive, ENOMEM,
2909				    "Out of memory for ZIP decompression");
2910				ret = ARCHIVE_FATAL;
2911				goto exit_mac_metadata;
2912			default:
2913				archive_set_error(&a->archive,
2914				    ARCHIVE_ERRNO_MISC,
2915				    "ZIP decompression failed (%d)", r);
2916				ret = ARCHIVE_FATAL;
2917				goto exit_mac_metadata;
2918			}
2919			bytes_used = zip->stream.total_in;
2920			metadata_bytes -= zip->stream.total_out;
2921			mp += zip->stream.total_out;
2922			break;
2923		}
2924#endif
2925		default:
2926			bytes_used = 0;
2927			break;
2928		}
2929		__archive_read_consume(a, bytes_used);
2930		remaining_bytes -= bytes_used;
2931	}
2932	archive_entry_copy_mac_metadata(entry, metadata,
2933	    (size_t)rsrc->uncompressed_size - metadata_bytes);
2934
2935exit_mac_metadata:
2936	__archive_read_seek(a, offset, SEEK_SET);
2937	zip->decompress_init = 0;
2938	free(metadata);
2939	return (ret);
2940}
2941
2942static int
2943archive_read_format_zip_seekable_read_header(struct archive_read *a,
2944	struct archive_entry *entry)
2945{
2946	struct zip *zip = (struct zip *)a->format->data;
2947	struct zip_entry *rsrc;
2948	int64_t offset;
2949	int r, ret = ARCHIVE_OK;
2950
2951	/*
2952	 * It should be sufficient to call archive_read_next_header() for
2953	 * a reader to determine if an entry is encrypted or not. If the
2954	 * encryption of an entry is only detectable when calling
2955	 * archive_read_data(), so be it. We'll do the same check there
2956	 * as well.
2957	 */
2958	if (zip->has_encrypted_entries ==
2959			ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW)
2960		zip->has_encrypted_entries = 0;
2961
2962	a->archive.archive_format = ARCHIVE_FORMAT_ZIP;
2963	if (a->archive.archive_format_name == NULL)
2964		a->archive.archive_format_name = "ZIP";
2965
2966	if (zip->zip_entries == NULL) {
2967		r = slurp_central_directory(a, zip);
2968		if (r != ARCHIVE_OK)
2969			return r;
2970		/* Get first entry whose local header offset is lower than
2971		 * other entries in the archive file. */
2972		zip->entry =
2973		    (struct zip_entry *)ARCHIVE_RB_TREE_MIN(&zip->tree);
2974	} else if (zip->entry != NULL) {
2975		/* Get next entry in local header offset order. */
2976		zip->entry = (struct zip_entry *)__archive_rb_tree_iterate(
2977		    &zip->tree, &zip->entry->node, ARCHIVE_RB_DIR_RIGHT);
2978	}
2979
2980	if (zip->entry == NULL)
2981		return ARCHIVE_EOF;
2982
2983	if (zip->entry->rsrcname.s)
2984		rsrc = (struct zip_entry *)__archive_rb_tree_find_node(
2985		    &zip->tree_rsrc, zip->entry->rsrcname.s);
2986	else
2987		rsrc = NULL;
2988
2989	if (zip->cctx_valid)
2990		archive_decrypto_aes_ctr_release(&zip->cctx);
2991	if (zip->hctx_valid)
2992		archive_hmac_sha1_cleanup(&zip->hctx);
2993	zip->tctx_valid = zip->cctx_valid = zip->hctx_valid = 0;
2994	__archive_read_reset_passphrase(a);
2995
2996	/* File entries are sorted by the header offset, we should mostly
2997	 * use __archive_read_consume to advance a read point to avoid redundant
2998	 * data reading.  */
2999	offset = archive_filter_bytes(&a->archive, 0);
3000	if (offset < zip->entry->local_header_offset)
3001		__archive_read_consume(a,
3002		    zip->entry->local_header_offset - offset);
3003	else if (offset != zip->entry->local_header_offset) {
3004		__archive_read_seek(a, zip->entry->local_header_offset,
3005		    SEEK_SET);
3006	}
3007	zip->unconsumed = 0;
3008	r = zip_read_local_file_header(a, entry, zip);
3009	if (r != ARCHIVE_OK)
3010		return r;
3011	if (rsrc) {
3012		int ret2 = zip_read_mac_metadata(a, entry, rsrc);
3013		if (ret2 < ret)
3014			ret = ret2;
3015	}
3016	return (ret);
3017}
3018
3019/*
3020 * We're going to seek for the next header anyway, so we don't
3021 * need to bother doing anything here.
3022 */
3023static int
3024archive_read_format_zip_read_data_skip_seekable(struct archive_read *a)
3025{
3026	struct zip *zip;
3027	zip = (struct zip *)(a->format->data);
3028
3029	zip->unconsumed = 0;
3030	return (ARCHIVE_OK);
3031}
3032
3033int
3034archive_read_support_format_zip_seekable(struct archive *_a)
3035{
3036	struct archive_read *a = (struct archive_read *)_a;
3037	struct zip *zip;
3038	int r;
3039
3040	archive_check_magic(_a, ARCHIVE_READ_MAGIC,
3041	    ARCHIVE_STATE_NEW, "archive_read_support_format_zip_seekable");
3042
3043	zip = (struct zip *)calloc(1, sizeof(*zip));
3044	if (zip == NULL) {
3045		archive_set_error(&a->archive, ENOMEM,
3046		    "Can't allocate zip data");
3047		return (ARCHIVE_FATAL);
3048	}
3049
3050#ifdef HAVE_COPYFILE_H
3051	/* Set this by default on Mac OS. */
3052	zip->process_mac_extensions = 1;
3053#endif
3054
3055	/*
3056	 * Until enough data has been read, we cannot tell about
3057	 * any encrypted entries yet.
3058	 */
3059	zip->has_encrypted_entries = ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW;
3060	zip->crc32func = real_crc32;
3061
3062	r = __archive_read_register_format(a,
3063	    zip,
3064	    "zip",
3065	    archive_read_format_zip_seekable_bid,
3066	    archive_read_format_zip_options,
3067	    archive_read_format_zip_seekable_read_header,
3068	    archive_read_format_zip_read_data,
3069	    archive_read_format_zip_read_data_skip_seekable,
3070	    NULL,
3071	    archive_read_format_zip_cleanup,
3072	    archive_read_support_format_zip_capabilities_seekable,
3073	    archive_read_format_zip_has_encrypted_entries);
3074
3075	if (r != ARCHIVE_OK)
3076		free(zip);
3077	return (ARCHIVE_OK);
3078}
3079