archive_read_support_format_zip.c revision 313926
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/11/contrib/libarchive/libarchive/archive_read_support_format_zip.c 313926 2017-02-18 21:58:56Z 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 decryption. */
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_decrypt_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_decrypt_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				uint64_t t = 0;
456				if (datasize < 8
457				    || (t = archive_le64dec(p + offset)) > INT64_MAX) {
458					archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
459					    "Malformed 64-bit uncompressed size");
460					return ARCHIVE_FAILED;
461				}
462				zip_entry->uncompressed_size = t;
463				offset += 8;
464				datasize -= 8;
465			}
466			if (zip_entry->compressed_size == 0xffffffff) {
467				uint64_t t = 0;
468				if (datasize < 8
469				    || (t = archive_le64dec(p + offset)) > INT64_MAX) {
470					archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
471					    "Malformed 64-bit compressed size");
472					return ARCHIVE_FAILED;
473				}
474				zip_entry->compressed_size = t;
475				offset += 8;
476				datasize -= 8;
477			}
478			if (zip_entry->local_header_offset == 0xffffffff) {
479				uint64_t t = 0;
480				if (datasize < 8
481				    || (t = archive_le64dec(p + offset)) > INT64_MAX) {
482					archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
483					    "Malformed 64-bit local header offset");
484					return ARCHIVE_FAILED;
485				}
486				zip_entry->local_header_offset = t;
487				offset += 8;
488				datasize -= 8;
489			}
490			/* archive_le32dec(p + offset) gives disk
491			 * on which file starts, but we don't handle
492			 * multi-volume Zip files. */
493			break;
494#ifdef DEBUG
495		case 0x0017:
496		{
497			/* Strong encryption field. */
498			if (archive_le16dec(p + offset) == 2) {
499				unsigned algId =
500					archive_le16dec(p + offset + 2);
501				unsigned bitLen =
502					archive_le16dec(p + offset + 4);
503				int	 flags =
504					archive_le16dec(p + offset + 6);
505				fprintf(stderr, "algId=0x%04x, bitLen=%u, "
506				    "flgas=%d\n", algId, bitLen,flags);
507			}
508			break;
509		}
510#endif
511		case 0x5455:
512		{
513			/* Extended time field "UT". */
514			int flags = p[offset];
515			offset++;
516			datasize--;
517			/* Flag bits indicate which dates are present. */
518			if (flags & 0x01)
519			{
520#ifdef DEBUG
521				fprintf(stderr, "mtime: %lld -> %d\n",
522				    (long long)zip_entry->mtime,
523				    archive_le32dec(p + offset));
524#endif
525				if (datasize < 4)
526					break;
527				zip_entry->mtime = archive_le32dec(p + offset);
528				offset += 4;
529				datasize -= 4;
530			}
531			if (flags & 0x02)
532			{
533				if (datasize < 4)
534					break;
535				zip_entry->atime = archive_le32dec(p + offset);
536				offset += 4;
537				datasize -= 4;
538			}
539			if (flags & 0x04)
540			{
541				if (datasize < 4)
542					break;
543				zip_entry->ctime = archive_le32dec(p + offset);
544				offset += 4;
545				datasize -= 4;
546			}
547			break;
548		}
549		case 0x5855:
550		{
551			/* Info-ZIP Unix Extra Field (old version) "UX". */
552			if (datasize >= 8) {
553				zip_entry->atime = archive_le32dec(p + offset);
554				zip_entry->mtime =
555				    archive_le32dec(p + offset + 4);
556			}
557			if (datasize >= 12) {
558				zip_entry->uid =
559				    archive_le16dec(p + offset + 8);
560				zip_entry->gid =
561				    archive_le16dec(p + offset + 10);
562			}
563			break;
564		}
565		case 0x6c78:
566		{
567			/* Experimental 'xl' field */
568			/*
569			 * Introduced Dec 2013 to provide a way to
570			 * include external file attributes (and other
571			 * fields that ordinarily appear only in
572			 * central directory) in local file header.
573			 * This provides file type and permission
574			 * information necessary to support full
575			 * streaming extraction.  Currently being
576			 * discussed with other Zip developers
577			 * ... subject to change.
578			 *
579			 * Format:
580			 *  The field starts with a bitmap that specifies
581			 *  which additional fields are included.  The
582			 *  bitmap is variable length and can be extended in
583			 *  the future.
584			 *
585			 *  n bytes - feature bitmap: first byte has low-order
586			 *    7 bits.  If high-order bit is set, a subsequent
587			 *    byte holds the next 7 bits, etc.
588			 *
589			 *  if bitmap & 1, 2 byte "version made by"
590			 *  if bitmap & 2, 2 byte "internal file attributes"
591			 *  if bitmap & 4, 4 byte "external file attributes"
592			 *  if bitmap & 8, 2 byte comment length + n byte comment
593			 */
594			int bitmap, bitmap_last;
595
596			if (datasize < 1)
597				break;
598			bitmap_last = bitmap = 0xff & p[offset];
599			offset += 1;
600			datasize -= 1;
601
602			/* We only support first 7 bits of bitmap; skip rest. */
603			while ((bitmap_last & 0x80) != 0
604			    && datasize >= 1) {
605				bitmap_last = p[offset];
606				offset += 1;
607				datasize -= 1;
608			}
609
610			if (bitmap & 1) {
611				/* 2 byte "version made by" */
612				if (datasize < 2)
613					break;
614				zip_entry->system
615				    = archive_le16dec(p + offset) >> 8;
616				offset += 2;
617				datasize -= 2;
618			}
619			if (bitmap & 2) {
620				/* 2 byte "internal file attributes" */
621				uint32_t internal_attributes;
622				if (datasize < 2)
623					break;
624				internal_attributes
625				    = archive_le16dec(p + offset);
626				/* Not used by libarchive at present. */
627				(void)internal_attributes; /* UNUSED */
628				offset += 2;
629				datasize -= 2;
630			}
631			if (bitmap & 4) {
632				/* 4 byte "external file attributes" */
633				uint32_t external_attributes;
634				if (datasize < 4)
635					break;
636				external_attributes
637				    = archive_le32dec(p + offset);
638				if (zip_entry->system == 3) {
639					zip_entry->mode
640					    = external_attributes >> 16;
641				} else if (zip_entry->system == 0) {
642					// Interpret MSDOS directory bit
643					if (0x10 == (external_attributes & 0x10)) {
644						zip_entry->mode = AE_IFDIR | 0775;
645					} else {
646						zip_entry->mode = AE_IFREG | 0664;
647					}
648					if (0x01 == (external_attributes & 0x01)) {
649						// Read-only bit; strip write permissions
650						zip_entry->mode &= 0555;
651					}
652				} else {
653					zip_entry->mode = 0;
654				}
655				offset += 4;
656				datasize -= 4;
657			}
658			if (bitmap & 8) {
659				/* 2 byte comment length + comment */
660				uint32_t comment_length;
661				if (datasize < 2)
662					break;
663				comment_length
664				    = archive_le16dec(p + offset);
665				offset += 2;
666				datasize -= 2;
667
668				if (datasize < comment_length)
669					break;
670				/* Comment is not supported by libarchive */
671				offset += comment_length;
672				datasize -= comment_length;
673			}
674			break;
675		}
676		case 0x7855:
677			/* Info-ZIP Unix Extra Field (type 2) "Ux". */
678#ifdef DEBUG
679			fprintf(stderr, "uid %d gid %d\n",
680			    archive_le16dec(p + offset),
681			    archive_le16dec(p + offset + 2));
682#endif
683			if (datasize >= 2)
684				zip_entry->uid = archive_le16dec(p + offset);
685			if (datasize >= 4)
686				zip_entry->gid =
687				    archive_le16dec(p + offset + 2);
688			break;
689		case 0x7875:
690		{
691			/* Info-Zip Unix Extra Field (type 3) "ux". */
692			int uidsize = 0, gidsize = 0;
693
694			/* TODO: support arbitrary uidsize/gidsize. */
695			if (datasize >= 1 && p[offset] == 1) {/* version=1 */
696				if (datasize >= 4) {
697					/* get a uid size. */
698					uidsize = 0xff & (int)p[offset+1];
699					if (uidsize == 2)
700						zip_entry->uid =
701						    archive_le16dec(
702						        p + offset + 2);
703					else if (uidsize == 4 && datasize >= 6)
704						zip_entry->uid =
705						    archive_le32dec(
706						        p + offset + 2);
707				}
708				if (datasize >= (2 + uidsize + 3)) {
709					/* get a gid size. */
710					gidsize = 0xff & (int)p[offset+2+uidsize];
711					if (gidsize == 2)
712						zip_entry->gid =
713						    archive_le16dec(
714						        p+offset+2+uidsize+1);
715					else if (gidsize == 4 &&
716					    datasize >= (2 + uidsize + 5))
717						zip_entry->gid =
718						    archive_le32dec(
719						        p+offset+2+uidsize+1);
720				}
721			}
722			break;
723		}
724		case 0x9901:
725			/* WinZip AES extra data field. */
726			if (p[offset + 2] == 'A' && p[offset + 3] == 'E') {
727				/* Vendor version. */
728				zip_entry->aes_extra.vendor =
729				    archive_le16dec(p + offset);
730				/* AES encryption strength. */
731				zip_entry->aes_extra.strength = p[offset + 4];
732				/* Actual compression method. */
733				zip_entry->aes_extra.compression =
734				    p[offset + 5];
735			}
736			break;
737		default:
738			break;
739		}
740		offset += datasize;
741	}
742	if (offset != extra_length) {
743		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
744		    "Malformed extra data: Consumed %d bytes of %d bytes",
745		    (int)offset, (int)extra_length);
746		return ARCHIVE_FAILED;
747	}
748	return ARCHIVE_OK;
749}
750
751/*
752 * Assumes file pointer is at beginning of local file header.
753 */
754static int
755zip_read_local_file_header(struct archive_read *a, struct archive_entry *entry,
756    struct zip *zip)
757{
758	const char *p;
759	const void *h;
760	const wchar_t *wp;
761	const char *cp;
762	size_t len, filename_length, extra_length;
763	struct archive_string_conv *sconv;
764	struct zip_entry *zip_entry = zip->entry;
765	struct zip_entry zip_entry_central_dir;
766	int ret = ARCHIVE_OK;
767	char version;
768
769	/* Save a copy of the original for consistency checks. */
770	zip_entry_central_dir = *zip_entry;
771
772	zip->decompress_init = 0;
773	zip->end_of_entry = 0;
774	zip->entry_uncompressed_bytes_read = 0;
775	zip->entry_compressed_bytes_read = 0;
776	zip->entry_crc32 = zip->crc32func(0, NULL, 0);
777
778	/* Setup default conversion. */
779	if (zip->sconv == NULL && !zip->init_default_conversion) {
780		zip->sconv_default =
781		    archive_string_default_conversion_for_read(&(a->archive));
782		zip->init_default_conversion = 1;
783	}
784
785	if ((p = __archive_read_ahead(a, 30, NULL)) == NULL) {
786		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
787		    "Truncated ZIP file header");
788		return (ARCHIVE_FATAL);
789	}
790
791	if (memcmp(p, "PK\003\004", 4) != 0) {
792		archive_set_error(&a->archive, -1, "Damaged Zip archive");
793		return ARCHIVE_FATAL;
794	}
795	version = p[4];
796	zip_entry->system = p[5];
797	zip_entry->zip_flags = archive_le16dec(p + 6);
798	if (zip_entry->zip_flags & (ZIP_ENCRYPTED | ZIP_STRONG_ENCRYPTED)) {
799		zip->has_encrypted_entries = 1;
800		archive_entry_set_is_data_encrypted(entry, 1);
801		if (zip_entry->zip_flags & ZIP_CENTRAL_DIRECTORY_ENCRYPTED &&
802			zip_entry->zip_flags & ZIP_ENCRYPTED &&
803			zip_entry->zip_flags & ZIP_STRONG_ENCRYPTED) {
804			archive_entry_set_is_metadata_encrypted(entry, 1);
805			return ARCHIVE_FATAL;
806		}
807	}
808	zip->init_decryption = (zip_entry->zip_flags & ZIP_ENCRYPTED);
809	zip_entry->compression = (char)archive_le16dec(p + 8);
810	zip_entry->mtime = zip_time(p + 10);
811	zip_entry->crc32 = archive_le32dec(p + 14);
812	if (zip_entry->zip_flags & ZIP_LENGTH_AT_END)
813		zip_entry->decdat = p[11];
814	else
815		zip_entry->decdat = p[17];
816	zip_entry->compressed_size = archive_le32dec(p + 18);
817	zip_entry->uncompressed_size = archive_le32dec(p + 22);
818	filename_length = archive_le16dec(p + 26);
819	extra_length = archive_le16dec(p + 28);
820
821	__archive_read_consume(a, 30);
822
823	/* Read the filename. */
824	if ((h = __archive_read_ahead(a, filename_length, NULL)) == NULL) {
825		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
826		    "Truncated ZIP file header");
827		return (ARCHIVE_FATAL);
828	}
829	if (zip_entry->zip_flags & ZIP_UTF8_NAME) {
830		/* The filename is stored to be UTF-8. */
831		if (zip->sconv_utf8 == NULL) {
832			zip->sconv_utf8 =
833			    archive_string_conversion_from_charset(
834				&a->archive, "UTF-8", 1);
835			if (zip->sconv_utf8 == NULL)
836				return (ARCHIVE_FATAL);
837		}
838		sconv = zip->sconv_utf8;
839	} else if (zip->sconv != NULL)
840		sconv = zip->sconv;
841	else
842		sconv = zip->sconv_default;
843
844	if (archive_entry_copy_pathname_l(entry,
845	    h, filename_length, sconv) != 0) {
846		if (errno == ENOMEM) {
847			archive_set_error(&a->archive, ENOMEM,
848			    "Can't allocate memory for Pathname");
849			return (ARCHIVE_FATAL);
850		}
851		archive_set_error(&a->archive,
852		    ARCHIVE_ERRNO_FILE_FORMAT,
853		    "Pathname cannot be converted "
854		    "from %s to current locale.",
855		    archive_string_conversion_charset_name(sconv));
856		ret = ARCHIVE_WARN;
857	}
858	__archive_read_consume(a, filename_length);
859
860	/* Read the extra data. */
861	if ((h = __archive_read_ahead(a, extra_length, NULL)) == NULL) {
862		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
863		    "Truncated ZIP file header");
864		return (ARCHIVE_FATAL);
865	}
866
867	if (ARCHIVE_OK != process_extra(a, h, extra_length, zip_entry)) {
868		return ARCHIVE_FATAL;
869	}
870	__archive_read_consume(a, extra_length);
871
872	/* Work around a bug in Info-Zip: When reading from a pipe, it
873	 * stats the pipe instead of synthesizing a file entry. */
874	if ((zip_entry->mode & AE_IFMT) == AE_IFIFO) {
875		zip_entry->mode &= ~ AE_IFMT;
876		zip_entry->mode |= AE_IFREG;
877	}
878
879	/* If the mode is totally empty, set some sane default. */
880	if (zip_entry->mode == 0) {
881		zip_entry->mode |= 0664;
882	}
883
884	/* Make sure that entries with a trailing '/' are marked as directories
885	 * even if the External File Attributes contains bogus values.  If this
886	 * is not a directory and there is no type, assume regularfile. */
887	if ((zip_entry->mode & AE_IFMT) != AE_IFDIR) {
888		int has_slash;
889
890		wp = archive_entry_pathname_w(entry);
891		if (wp != NULL) {
892			len = wcslen(wp);
893			has_slash = len > 0 && wp[len - 1] == L'/';
894		} else {
895			cp = archive_entry_pathname(entry);
896			len = (cp != NULL)?strlen(cp):0;
897			has_slash = len > 0 && cp[len - 1] == '/';
898		}
899		/* Correct file type as needed. */
900		if (has_slash) {
901			zip_entry->mode &= ~AE_IFMT;
902			zip_entry->mode |= AE_IFDIR;
903			zip_entry->mode |= 0111;
904		} else if ((zip_entry->mode & AE_IFMT) == 0) {
905			zip_entry->mode |= AE_IFREG;
906		}
907	}
908
909	/* Make sure directories end in '/' */
910	if ((zip_entry->mode & AE_IFMT) == AE_IFDIR) {
911		wp = archive_entry_pathname_w(entry);
912		if (wp != NULL) {
913			len = wcslen(wp);
914			if (len > 0 && wp[len - 1] != L'/') {
915				struct archive_wstring s;
916				archive_string_init(&s);
917				archive_wstrcat(&s, wp);
918				archive_wstrappend_wchar(&s, L'/');
919				archive_entry_copy_pathname_w(entry, s.s);
920				archive_wstring_free(&s);
921			}
922		} else {
923			cp = archive_entry_pathname(entry);
924			len = (cp != NULL)?strlen(cp):0;
925			if (len > 0 && cp[len - 1] != '/') {
926				struct archive_string s;
927				archive_string_init(&s);
928				archive_strcat(&s, cp);
929				archive_strappend_char(&s, '/');
930				archive_entry_set_pathname(entry, s.s);
931				archive_string_free(&s);
932			}
933		}
934	}
935
936	if (zip_entry->flags & LA_FROM_CENTRAL_DIRECTORY) {
937		/* If this came from the central dir, it's size info
938		 * is definitive, so ignore the length-at-end flag. */
939		zip_entry->zip_flags &= ~ZIP_LENGTH_AT_END;
940		/* If local header is missing a value, use the one from
941		   the central directory.  If both have it, warn about
942		   mismatches. */
943		if (zip_entry->crc32 == 0) {
944			zip_entry->crc32 = zip_entry_central_dir.crc32;
945		} else if (!zip->ignore_crc32
946		    && zip_entry->crc32 != zip_entry_central_dir.crc32) {
947			archive_set_error(&a->archive,
948			    ARCHIVE_ERRNO_FILE_FORMAT,
949			    "Inconsistent CRC32 values");
950			ret = ARCHIVE_WARN;
951		}
952		if (zip_entry->compressed_size == 0) {
953			zip_entry->compressed_size
954			    = zip_entry_central_dir.compressed_size;
955		} else if (zip_entry->compressed_size
956		    != zip_entry_central_dir.compressed_size) {
957			archive_set_error(&a->archive,
958			    ARCHIVE_ERRNO_FILE_FORMAT,
959			    "Inconsistent compressed size: "
960			    "%jd in central directory, %jd in local header",
961			    (intmax_t)zip_entry_central_dir.compressed_size,
962			    (intmax_t)zip_entry->compressed_size);
963			ret = ARCHIVE_WARN;
964		}
965		if (zip_entry->uncompressed_size == 0) {
966			zip_entry->uncompressed_size
967			    = zip_entry_central_dir.uncompressed_size;
968		} else if (zip_entry->uncompressed_size
969		    != zip_entry_central_dir.uncompressed_size) {
970			archive_set_error(&a->archive,
971			    ARCHIVE_ERRNO_FILE_FORMAT,
972			    "Inconsistent uncompressed size: "
973			    "%jd in central directory, %jd in local header",
974			    (intmax_t)zip_entry_central_dir.uncompressed_size,
975			    (intmax_t)zip_entry->uncompressed_size);
976			ret = ARCHIVE_WARN;
977		}
978	}
979
980	/* Populate some additional entry fields: */
981	archive_entry_set_mode(entry, zip_entry->mode);
982	archive_entry_set_uid(entry, zip_entry->uid);
983	archive_entry_set_gid(entry, zip_entry->gid);
984	archive_entry_set_mtime(entry, zip_entry->mtime, 0);
985	archive_entry_set_ctime(entry, zip_entry->ctime, 0);
986	archive_entry_set_atime(entry, zip_entry->atime, 0);
987
988	if ((zip->entry->mode & AE_IFMT) == AE_IFLNK) {
989		size_t linkname_length;
990
991		if (zip_entry->compressed_size > 64 * 1024) {
992			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
993			    "Zip file with oversized link entry");
994			return ARCHIVE_FATAL;
995		}
996
997		linkname_length = (size_t)zip_entry->compressed_size;
998
999		archive_entry_set_size(entry, 0);
1000		p = __archive_read_ahead(a, linkname_length, NULL);
1001		if (p == NULL) {
1002			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1003			    "Truncated Zip file");
1004			return ARCHIVE_FATAL;
1005		}
1006
1007		sconv = zip->sconv;
1008		if (sconv == NULL && (zip->entry->zip_flags & ZIP_UTF8_NAME))
1009			sconv = zip->sconv_utf8;
1010		if (sconv == NULL)
1011			sconv = zip->sconv_default;
1012		if (archive_entry_copy_symlink_l(entry, p, linkname_length,
1013		    sconv) != 0) {
1014			if (errno != ENOMEM && sconv == zip->sconv_utf8 &&
1015			    (zip->entry->zip_flags & ZIP_UTF8_NAME))
1016			    archive_entry_copy_symlink_l(entry, p,
1017				linkname_length, NULL);
1018			if (errno == ENOMEM) {
1019				archive_set_error(&a->archive, ENOMEM,
1020				    "Can't allocate memory for Symlink");
1021				return (ARCHIVE_FATAL);
1022			}
1023			/*
1024			 * Since there is no character-set regulation for
1025			 * symlink name, do not report the conversion error
1026			 * in an automatic conversion.
1027			 */
1028			if (sconv != zip->sconv_utf8 ||
1029			    (zip->entry->zip_flags & ZIP_UTF8_NAME) == 0) {
1030				archive_set_error(&a->archive,
1031				    ARCHIVE_ERRNO_FILE_FORMAT,
1032				    "Symlink cannot be converted "
1033				    "from %s to current locale.",
1034				    archive_string_conversion_charset_name(
1035					sconv));
1036				ret = ARCHIVE_WARN;
1037			}
1038		}
1039		zip_entry->uncompressed_size = zip_entry->compressed_size = 0;
1040
1041		if (__archive_read_consume(a, linkname_length) < 0) {
1042			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1043			    "Read error skipping symlink target name");
1044			return ARCHIVE_FATAL;
1045		}
1046	} else if (0 == (zip_entry->zip_flags & ZIP_LENGTH_AT_END)
1047	    || zip_entry->uncompressed_size > 0) {
1048		/* Set the size only if it's meaningful. */
1049		archive_entry_set_size(entry, zip_entry->uncompressed_size);
1050	}
1051	zip->entry_bytes_remaining = zip_entry->compressed_size;
1052
1053	/* If there's no body, force read_data() to return EOF immediately. */
1054	if (0 == (zip_entry->zip_flags & ZIP_LENGTH_AT_END)
1055	    && zip->entry_bytes_remaining < 1)
1056		zip->end_of_entry = 1;
1057
1058	/* Set up a more descriptive format name. */
1059	archive_string_sprintf(&zip->format_name, "ZIP %d.%d (%s)",
1060	    version / 10, version % 10,
1061	    compression_name(zip->entry->compression));
1062	a->archive.archive_format_name = zip->format_name.s;
1063
1064	return (ret);
1065}
1066
1067static int
1068check_authentication_code(struct archive_read *a, const void *_p)
1069{
1070	struct zip *zip = (struct zip *)(a->format->data);
1071
1072	/* Check authentication code. */
1073	if (zip->hctx_valid) {
1074		const void *p;
1075		uint8_t hmac[20];
1076		size_t hmac_len = 20;
1077		int cmp;
1078
1079		archive_hmac_sha1_final(&zip->hctx, hmac, &hmac_len);
1080		if (_p == NULL) {
1081			/* Read authentication code. */
1082			p = __archive_read_ahead(a, AUTH_CODE_SIZE, NULL);
1083			if (p == NULL) {
1084				archive_set_error(&a->archive,
1085				    ARCHIVE_ERRNO_FILE_FORMAT,
1086				    "Truncated ZIP file data");
1087				return (ARCHIVE_FATAL);
1088			}
1089		} else {
1090			p = _p;
1091		}
1092		cmp = memcmp(hmac, p, AUTH_CODE_SIZE);
1093		__archive_read_consume(a, AUTH_CODE_SIZE);
1094		if (cmp != 0) {
1095			archive_set_error(&a->archive,
1096			    ARCHIVE_ERRNO_MISC,
1097			    "ZIP bad Authentication code");
1098			return (ARCHIVE_WARN);
1099		}
1100	}
1101	return (ARCHIVE_OK);
1102}
1103
1104/*
1105 * Read "uncompressed" data.  There are three cases:
1106 *  1) We know the size of the data.  This is always true for the
1107 * seeking reader (we've examined the Central Directory already).
1108 *  2) ZIP_LENGTH_AT_END was set, but only the CRC was deferred.
1109 * Info-ZIP seems to do this; we know the size but have to grab
1110 * the CRC from the data descriptor afterwards.
1111 *  3) We're streaming and ZIP_LENGTH_AT_END was specified and
1112 * we have no size information.  In this case, we can do pretty
1113 * well by watching for the data descriptor record.  The data
1114 * descriptor is 16 bytes and includes a computed CRC that should
1115 * provide a strong check.
1116 *
1117 * TODO: Technically, the PK\007\010 signature is optional.
1118 * In the original spec, the data descriptor contained CRC
1119 * and size fields but had no leading signature.  In practice,
1120 * newer writers seem to provide the signature pretty consistently.
1121 *
1122 * For uncompressed data, the PK\007\010 marker seems essential
1123 * to be sure we've actually seen the end of the entry.
1124 *
1125 * Returns ARCHIVE_OK if successful, ARCHIVE_FATAL otherwise, sets
1126 * zip->end_of_entry if it consumes all of the data.
1127 */
1128static int
1129zip_read_data_none(struct archive_read *a, const void **_buff,
1130    size_t *size, int64_t *offset)
1131{
1132	struct zip *zip;
1133	const char *buff;
1134	ssize_t bytes_avail;
1135	int r;
1136
1137	(void)offset; /* UNUSED */
1138
1139	zip = (struct zip *)(a->format->data);
1140
1141	if (zip->entry->zip_flags & ZIP_LENGTH_AT_END) {
1142		const char *p;
1143		ssize_t grabbing_bytes = 24;
1144
1145		if (zip->hctx_valid)
1146			grabbing_bytes += AUTH_CODE_SIZE;
1147		/* Grab at least 24 bytes. */
1148		buff = __archive_read_ahead(a, grabbing_bytes, &bytes_avail);
1149		if (bytes_avail < grabbing_bytes) {
1150			/* Zip archives have end-of-archive markers
1151			   that are longer than this, so a failure to get at
1152			   least 24 bytes really does indicate a truncated
1153			   file. */
1154			archive_set_error(&a->archive,
1155			    ARCHIVE_ERRNO_FILE_FORMAT,
1156			    "Truncated ZIP file data");
1157			return (ARCHIVE_FATAL);
1158		}
1159		/* Check for a complete PK\007\010 signature, followed
1160		 * by the correct 4-byte CRC. */
1161		p = buff;
1162		if (zip->hctx_valid)
1163			p += AUTH_CODE_SIZE;
1164		if (p[0] == 'P' && p[1] == 'K'
1165		    && p[2] == '\007' && p[3] == '\010'
1166		    && (archive_le32dec(p + 4) == zip->entry_crc32
1167			|| zip->ignore_crc32
1168			|| (zip->hctx_valid
1169			 && zip->entry->aes_extra.vendor == AES_VENDOR_AE_2))) {
1170			if (zip->entry->flags & LA_USED_ZIP64) {
1171				uint64_t compressed, uncompressed;
1172				zip->entry->crc32 = archive_le32dec(p + 4);
1173				compressed = archive_le64dec(p + 8);
1174				uncompressed = archive_le64dec(p + 16);
1175				if (compressed > INT64_MAX || uncompressed > INT64_MAX) {
1176					archive_set_error(&a->archive,
1177					    ARCHIVE_ERRNO_FILE_FORMAT,
1178					    "Overflow of 64-bit file sizes");
1179					return ARCHIVE_FAILED;
1180				}
1181				zip->entry->compressed_size = compressed;
1182				zip->entry->uncompressed_size = uncompressed;
1183				zip->unconsumed = 24;
1184			} else {
1185				zip->entry->crc32 = archive_le32dec(p + 4);
1186				zip->entry->compressed_size =
1187					archive_le32dec(p + 8);
1188				zip->entry->uncompressed_size =
1189					archive_le32dec(p + 12);
1190				zip->unconsumed = 16;
1191			}
1192			if (zip->hctx_valid) {
1193				r = check_authentication_code(a, buff);
1194				if (r != ARCHIVE_OK)
1195					return (r);
1196			}
1197			zip->end_of_entry = 1;
1198			return (ARCHIVE_OK);
1199		}
1200		/* If not at EOF, ensure we consume at least one byte. */
1201		++p;
1202
1203		/* Scan forward until we see where a PK\007\010 signature
1204		 * might be. */
1205		/* Return bytes up until that point.  On the next call,
1206		 * the code above will verify the data descriptor. */
1207		while (p < buff + bytes_avail - 4) {
1208			if (p[3] == 'P') { p += 3; }
1209			else if (p[3] == 'K') { p += 2; }
1210			else if (p[3] == '\007') { p += 1; }
1211			else if (p[3] == '\010' && p[2] == '\007'
1212			    && p[1] == 'K' && p[0] == 'P') {
1213				if (zip->hctx_valid)
1214					p -= AUTH_CODE_SIZE;
1215				break;
1216			} else { p += 4; }
1217		}
1218		bytes_avail = p - buff;
1219	} else {
1220		if (zip->entry_bytes_remaining == 0) {
1221			zip->end_of_entry = 1;
1222			if (zip->hctx_valid) {
1223				r = check_authentication_code(a, NULL);
1224				if (r != ARCHIVE_OK)
1225					return (r);
1226			}
1227			return (ARCHIVE_OK);
1228		}
1229		/* Grab a bunch of bytes. */
1230		buff = __archive_read_ahead(a, 1, &bytes_avail);
1231		if (bytes_avail <= 0) {
1232			archive_set_error(&a->archive,
1233			    ARCHIVE_ERRNO_FILE_FORMAT,
1234			    "Truncated ZIP file data");
1235			return (ARCHIVE_FATAL);
1236		}
1237		if (bytes_avail > zip->entry_bytes_remaining)
1238			bytes_avail = (ssize_t)zip->entry_bytes_remaining;
1239	}
1240	if (zip->tctx_valid || zip->cctx_valid) {
1241		size_t dec_size = bytes_avail;
1242
1243		if (dec_size > zip->decrypted_buffer_size)
1244			dec_size = zip->decrypted_buffer_size;
1245		if (zip->tctx_valid) {
1246			trad_enc_decrypt_update(&zip->tctx,
1247			    (const uint8_t *)buff, dec_size,
1248			    zip->decrypted_buffer, dec_size);
1249		} else {
1250			size_t dsize = dec_size;
1251			archive_hmac_sha1_update(&zip->hctx,
1252			    (const uint8_t *)buff, dec_size);
1253			archive_decrypto_aes_ctr_update(&zip->cctx,
1254			    (const uint8_t *)buff, dec_size,
1255			    zip->decrypted_buffer, &dsize);
1256		}
1257		bytes_avail = dec_size;
1258		buff = (const char *)zip->decrypted_buffer;
1259	}
1260	*size = bytes_avail;
1261	zip->entry_bytes_remaining -= bytes_avail;
1262	zip->entry_uncompressed_bytes_read += bytes_avail;
1263	zip->entry_compressed_bytes_read += bytes_avail;
1264	zip->unconsumed += bytes_avail;
1265	*_buff = buff;
1266	return (ARCHIVE_OK);
1267}
1268
1269#ifdef HAVE_ZLIB_H
1270static int
1271zip_deflate_init(struct archive_read *a, struct zip *zip)
1272{
1273	int r;
1274
1275	/* If we haven't yet read any data, initialize the decompressor. */
1276	if (!zip->decompress_init) {
1277		if (zip->stream_valid)
1278			r = inflateReset(&zip->stream);
1279		else
1280			r = inflateInit2(&zip->stream,
1281			    -15 /* Don't check for zlib header */);
1282		if (r != Z_OK) {
1283			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1284			    "Can't initialize ZIP decompression.");
1285			return (ARCHIVE_FATAL);
1286		}
1287		/* Stream structure has been set up. */
1288		zip->stream_valid = 1;
1289		/* We've initialized decompression for this stream. */
1290		zip->decompress_init = 1;
1291	}
1292	return (ARCHIVE_OK);
1293}
1294
1295static int
1296zip_read_data_deflate(struct archive_read *a, const void **buff,
1297    size_t *size, int64_t *offset)
1298{
1299	struct zip *zip;
1300	ssize_t bytes_avail;
1301	const void *compressed_buff, *sp;
1302	int r;
1303
1304	(void)offset; /* UNUSED */
1305
1306	zip = (struct zip *)(a->format->data);
1307
1308	/* If the buffer hasn't been allocated, allocate it now. */
1309	if (zip->uncompressed_buffer == NULL) {
1310		zip->uncompressed_buffer_size = 256 * 1024;
1311		zip->uncompressed_buffer
1312		    = (unsigned char *)malloc(zip->uncompressed_buffer_size);
1313		if (zip->uncompressed_buffer == NULL) {
1314			archive_set_error(&a->archive, ENOMEM,
1315			    "No memory for ZIP decompression");
1316			return (ARCHIVE_FATAL);
1317		}
1318	}
1319
1320	r = zip_deflate_init(a, zip);
1321	if (r != ARCHIVE_OK)
1322		return (r);
1323
1324	/*
1325	 * Note: '1' here is a performance optimization.
1326	 * Recall that the decompression layer returns a count of
1327	 * available bytes; asking for more than that forces the
1328	 * decompressor to combine reads by copying data.
1329	 */
1330	compressed_buff = sp = __archive_read_ahead(a, 1, &bytes_avail);
1331	if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END)
1332	    && bytes_avail > zip->entry_bytes_remaining) {
1333		bytes_avail = (ssize_t)zip->entry_bytes_remaining;
1334	}
1335	if (bytes_avail < 0) {
1336		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1337		    "Truncated ZIP file body");
1338		return (ARCHIVE_FATAL);
1339	}
1340
1341	if (zip->tctx_valid || zip->cctx_valid) {
1342		if (zip->decrypted_bytes_remaining < (size_t)bytes_avail) {
1343			size_t buff_remaining =
1344			    (zip->decrypted_buffer + zip->decrypted_buffer_size)
1345			    - (zip->decrypted_ptr + zip->decrypted_bytes_remaining);
1346
1347			if (buff_remaining > (size_t)bytes_avail)
1348				buff_remaining = (size_t)bytes_avail;
1349
1350			if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END) &&
1351			      zip->entry_bytes_remaining > 0) {
1352				if ((int64_t)(zip->decrypted_bytes_remaining
1353				    + buff_remaining)
1354				      > zip->entry_bytes_remaining) {
1355					if (zip->entry_bytes_remaining <
1356					      (int64_t)zip->decrypted_bytes_remaining)
1357						buff_remaining = 0;
1358					else
1359						buff_remaining =
1360						    (size_t)zip->entry_bytes_remaining
1361						      - zip->decrypted_bytes_remaining;
1362				}
1363			}
1364			if (buff_remaining > 0) {
1365				if (zip->tctx_valid) {
1366					trad_enc_decrypt_update(&zip->tctx,
1367					    compressed_buff, buff_remaining,
1368					    zip->decrypted_ptr
1369					      + zip->decrypted_bytes_remaining,
1370					    buff_remaining);
1371				} else {
1372					size_t dsize = buff_remaining;
1373					archive_decrypto_aes_ctr_update(
1374					    &zip->cctx,
1375					    compressed_buff, buff_remaining,
1376					    zip->decrypted_ptr
1377					      + zip->decrypted_bytes_remaining,
1378					    &dsize);
1379				}
1380				zip->decrypted_bytes_remaining += buff_remaining;
1381			}
1382		}
1383		bytes_avail = zip->decrypted_bytes_remaining;
1384		compressed_buff = (const char *)zip->decrypted_ptr;
1385	}
1386
1387	/*
1388	 * A bug in zlib.h: stream.next_in should be marked 'const'
1389	 * but isn't (the library never alters data through the
1390	 * next_in pointer, only reads it).  The result: this ugly
1391	 * cast to remove 'const'.
1392	 */
1393	zip->stream.next_in = (Bytef *)(uintptr_t)(const void *)compressed_buff;
1394	zip->stream.avail_in = (uInt)bytes_avail;
1395	zip->stream.total_in = 0;
1396	zip->stream.next_out = zip->uncompressed_buffer;
1397	zip->stream.avail_out = (uInt)zip->uncompressed_buffer_size;
1398	zip->stream.total_out = 0;
1399
1400	r = inflate(&zip->stream, 0);
1401	switch (r) {
1402	case Z_OK:
1403		break;
1404	case Z_STREAM_END:
1405		zip->end_of_entry = 1;
1406		break;
1407	case Z_MEM_ERROR:
1408		archive_set_error(&a->archive, ENOMEM,
1409		    "Out of memory for ZIP decompression");
1410		return (ARCHIVE_FATAL);
1411	default:
1412		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1413		    "ZIP decompression failed (%d)", r);
1414		return (ARCHIVE_FATAL);
1415	}
1416
1417	/* Consume as much as the compressor actually used. */
1418	bytes_avail = zip->stream.total_in;
1419	if (zip->tctx_valid || zip->cctx_valid) {
1420		zip->decrypted_bytes_remaining -= bytes_avail;
1421		if (zip->decrypted_bytes_remaining == 0)
1422			zip->decrypted_ptr = zip->decrypted_buffer;
1423		else
1424			zip->decrypted_ptr += bytes_avail;
1425	}
1426	/* Calculate compressed data as much as we used.*/
1427	if (zip->hctx_valid)
1428		archive_hmac_sha1_update(&zip->hctx, sp, bytes_avail);
1429	__archive_read_consume(a, bytes_avail);
1430	zip->entry_bytes_remaining -= bytes_avail;
1431	zip->entry_compressed_bytes_read += bytes_avail;
1432
1433	*size = zip->stream.total_out;
1434	zip->entry_uncompressed_bytes_read += zip->stream.total_out;
1435	*buff = zip->uncompressed_buffer;
1436
1437	if (zip->end_of_entry && zip->hctx_valid) {
1438		r = check_authentication_code(a, NULL);
1439		if (r != ARCHIVE_OK)
1440			return (r);
1441	}
1442
1443	if (zip->end_of_entry && (zip->entry->zip_flags & ZIP_LENGTH_AT_END)) {
1444		const char *p;
1445
1446		if (NULL == (p = __archive_read_ahead(a, 24, NULL))) {
1447			archive_set_error(&a->archive,
1448			    ARCHIVE_ERRNO_FILE_FORMAT,
1449			    "Truncated ZIP end-of-file record");
1450			return (ARCHIVE_FATAL);
1451		}
1452		/* Consume the optional PK\007\010 marker. */
1453		if (p[0] == 'P' && p[1] == 'K' &&
1454		    p[2] == '\007' && p[3] == '\010') {
1455			p += 4;
1456			zip->unconsumed = 4;
1457		}
1458		if (zip->entry->flags & LA_USED_ZIP64) {
1459			uint64_t compressed, uncompressed;
1460			zip->entry->crc32 = archive_le32dec(p);
1461			compressed = archive_le64dec(p + 4);
1462			uncompressed = archive_le64dec(p + 12);
1463			if (compressed > INT64_MAX || uncompressed > INT64_MAX) {
1464				archive_set_error(&a->archive,
1465				    ARCHIVE_ERRNO_FILE_FORMAT,
1466				    "Overflow of 64-bit file sizes");
1467				return ARCHIVE_FAILED;
1468			}
1469			zip->entry->compressed_size = compressed;
1470			zip->entry->uncompressed_size = uncompressed;
1471			zip->unconsumed += 20;
1472		} else {
1473			zip->entry->crc32 = archive_le32dec(p);
1474			zip->entry->compressed_size = archive_le32dec(p + 4);
1475			zip->entry->uncompressed_size = archive_le32dec(p + 8);
1476			zip->unconsumed += 12;
1477		}
1478	}
1479
1480	return (ARCHIVE_OK);
1481}
1482#endif
1483
1484static int
1485read_decryption_header(struct archive_read *a)
1486{
1487	struct zip *zip = (struct zip *)(a->format->data);
1488	const char *p;
1489	unsigned int remaining_size;
1490	unsigned int ts;
1491
1492	/*
1493	 * Read an initialization vector data field.
1494	 */
1495	p = __archive_read_ahead(a, 2, NULL);
1496	if (p == NULL)
1497		goto truncated;
1498	ts = zip->iv_size;
1499	zip->iv_size = archive_le16dec(p);
1500	__archive_read_consume(a, 2);
1501	if (ts < zip->iv_size) {
1502		free(zip->iv);
1503		zip->iv = NULL;
1504	}
1505	p = __archive_read_ahead(a, zip->iv_size, NULL);
1506	if (p == NULL)
1507		goto truncated;
1508	if (zip->iv == NULL) {
1509		zip->iv = malloc(zip->iv_size);
1510		if (zip->iv == NULL)
1511			goto nomem;
1512	}
1513	memcpy(zip->iv, p, zip->iv_size);
1514	__archive_read_consume(a, zip->iv_size);
1515
1516	/*
1517	 * Read a size of remaining decryption header field.
1518	 */
1519	p = __archive_read_ahead(a, 14, NULL);
1520	if (p == NULL)
1521		goto truncated;
1522	remaining_size = archive_le32dec(p);
1523	if (remaining_size < 16 || remaining_size > (1 << 18))
1524		goto corrupted;
1525
1526	/* Check if format version is supported. */
1527	if (archive_le16dec(p+4) != 3) {
1528		archive_set_error(&a->archive,
1529		    ARCHIVE_ERRNO_FILE_FORMAT,
1530		    "Unsupported encryption format version: %u",
1531		    archive_le16dec(p+4));
1532		return (ARCHIVE_FAILED);
1533	}
1534
1535	/*
1536	 * Read an encryption algorithm field.
1537	 */
1538	zip->alg_id = archive_le16dec(p+6);
1539	switch (zip->alg_id) {
1540	case 0x6601:/* DES */
1541	case 0x6602:/* RC2 */
1542	case 0x6603:/* 3DES 168 */
1543	case 0x6609:/* 3DES 112 */
1544	case 0x660E:/* AES 128 */
1545	case 0x660F:/* AES 192 */
1546	case 0x6610:/* AES 256 */
1547	case 0x6702:/* RC2 (version >= 5.2) */
1548	case 0x6720:/* Blowfish */
1549	case 0x6721:/* Twofish */
1550	case 0x6801:/* RC4 */
1551		/* Supported encryption algorithm. */
1552		break;
1553	default:
1554		archive_set_error(&a->archive,
1555		    ARCHIVE_ERRNO_FILE_FORMAT,
1556		    "Unknown encryption algorithm: %u", zip->alg_id);
1557		return (ARCHIVE_FAILED);
1558	}
1559
1560	/*
1561	 * Read a bit length field.
1562	 */
1563	zip->bit_len = archive_le16dec(p+8);
1564
1565	/*
1566	 * Read a flags field.
1567	 */
1568	zip->flags = archive_le16dec(p+10);
1569	switch (zip->flags & 0xf000) {
1570	case 0x0001: /* Password is required to decrypt. */
1571	case 0x0002: /* Certificates only. */
1572	case 0x0003: /* Password or certificate required to decrypt. */
1573		break;
1574	default:
1575		archive_set_error(&a->archive,
1576		    ARCHIVE_ERRNO_FILE_FORMAT,
1577		    "Unknown encryption flag: %u", zip->flags);
1578		return (ARCHIVE_FAILED);
1579	}
1580	if ((zip->flags & 0xf000) == 0 ||
1581	    (zip->flags & 0xf000) == 0x4000) {
1582		archive_set_error(&a->archive,
1583		    ARCHIVE_ERRNO_FILE_FORMAT,
1584		    "Unknown encryption flag: %u", zip->flags);
1585		return (ARCHIVE_FAILED);
1586	}
1587
1588	/*
1589	 * Read an encrypted random data field.
1590	 */
1591	ts = zip->erd_size;
1592	zip->erd_size = archive_le16dec(p+12);
1593	__archive_read_consume(a, 14);
1594	if ((zip->erd_size & 0xf) != 0 ||
1595	    (zip->erd_size + 16) > remaining_size ||
1596	    (zip->erd_size + 16) < zip->erd_size)
1597		goto corrupted;
1598
1599	if (ts < zip->erd_size) {
1600		free(zip->erd);
1601		zip->erd = NULL;
1602	}
1603	p = __archive_read_ahead(a, zip->erd_size, NULL);
1604	if (p == NULL)
1605		goto truncated;
1606	if (zip->erd == NULL) {
1607		zip->erd = malloc(zip->erd_size);
1608		if (zip->erd == NULL)
1609			goto nomem;
1610	}
1611	memcpy(zip->erd, p, zip->erd_size);
1612	__archive_read_consume(a, zip->erd_size);
1613
1614	/*
1615	 * Read a reserved data field.
1616	 */
1617	p = __archive_read_ahead(a, 4, NULL);
1618	if (p == NULL)
1619		goto truncated;
1620	/* Reserved data size should be zero. */
1621	if (archive_le32dec(p) != 0)
1622		goto corrupted;
1623	__archive_read_consume(a, 4);
1624
1625	/*
1626	 * Read a password validation data field.
1627	 */
1628	p = __archive_read_ahead(a, 2, NULL);
1629	if (p == NULL)
1630		goto truncated;
1631	ts = zip->v_size;
1632	zip->v_size = archive_le16dec(p);
1633	__archive_read_consume(a, 2);
1634	if ((zip->v_size & 0x0f) != 0 ||
1635	    (zip->erd_size + zip->v_size + 16) > remaining_size ||
1636	    (zip->erd_size + zip->v_size + 16) < (zip->erd_size + zip->v_size))
1637		goto corrupted;
1638	if (ts < zip->v_size) {
1639		free(zip->v_data);
1640		zip->v_data = NULL;
1641	}
1642	p = __archive_read_ahead(a, zip->v_size, NULL);
1643	if (p == NULL)
1644		goto truncated;
1645	if (zip->v_data == NULL) {
1646		zip->v_data = malloc(zip->v_size);
1647		if (zip->v_data == NULL)
1648			goto nomem;
1649	}
1650	memcpy(zip->v_data, p, zip->v_size);
1651	__archive_read_consume(a, zip->v_size);
1652
1653	p = __archive_read_ahead(a, 4, NULL);
1654	if (p == NULL)
1655		goto truncated;
1656	zip->v_crc32 = archive_le32dec(p);
1657	__archive_read_consume(a, 4);
1658
1659	/*return (ARCHIVE_OK);
1660	 * This is not fully implemented yet.*/
1661	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1662	    "Encrypted file is unsupported");
1663	return (ARCHIVE_FAILED);
1664truncated:
1665	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1666	    "Truncated ZIP file data");
1667	return (ARCHIVE_FATAL);
1668corrupted:
1669	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1670	    "Corrupted ZIP file data");
1671	return (ARCHIVE_FATAL);
1672nomem:
1673	archive_set_error(&a->archive, ENOMEM,
1674	    "No memory for ZIP decryption");
1675	return (ARCHIVE_FATAL);
1676}
1677
1678static int
1679zip_alloc_decryption_buffer(struct archive_read *a)
1680{
1681	struct zip *zip = (struct zip *)(a->format->data);
1682	size_t bs = 256 * 1024;
1683
1684	if (zip->decrypted_buffer == NULL) {
1685		zip->decrypted_buffer_size = bs;
1686		zip->decrypted_buffer = malloc(bs);
1687		if (zip->decrypted_buffer == NULL) {
1688			archive_set_error(&a->archive, ENOMEM,
1689			    "No memory for ZIP decryption");
1690			return (ARCHIVE_FATAL);
1691		}
1692	}
1693	zip->decrypted_ptr = zip->decrypted_buffer;
1694	return (ARCHIVE_OK);
1695}
1696
1697static int
1698init_traditional_PKWARE_decryption(struct archive_read *a)
1699{
1700	struct zip *zip = (struct zip *)(a->format->data);
1701	const void *p;
1702	int retry;
1703	int r;
1704
1705	if (zip->tctx_valid)
1706		return (ARCHIVE_OK);
1707
1708	/*
1709	   Read the 12 bytes encryption header stored at
1710	   the start of the data area.
1711	 */
1712#define ENC_HEADER_SIZE	12
1713	if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END)
1714	    && zip->entry_bytes_remaining < ENC_HEADER_SIZE) {
1715		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1716		    "Truncated Zip encrypted body: only %jd bytes available",
1717		    (intmax_t)zip->entry_bytes_remaining);
1718		return (ARCHIVE_FATAL);
1719	}
1720
1721	p = __archive_read_ahead(a, ENC_HEADER_SIZE, NULL);
1722	if (p == NULL) {
1723		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1724		    "Truncated ZIP file data");
1725		return (ARCHIVE_FATAL);
1726	}
1727
1728	for (retry = 0;; retry++) {
1729		const char *passphrase;
1730		uint8_t crcchk;
1731
1732		passphrase = __archive_read_next_passphrase(a);
1733		if (passphrase == NULL) {
1734			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1735			    (retry > 0)?
1736				"Incorrect passphrase":
1737				"Passphrase required for this entry");
1738			return (ARCHIVE_FAILED);
1739		}
1740
1741		/*
1742		 * Initialize ctx for Traditional PKWARE Decryption.
1743		 */
1744		r = trad_enc_init(&zip->tctx, passphrase, strlen(passphrase),
1745			p, ENC_HEADER_SIZE, &crcchk);
1746		if (r == 0 && crcchk == zip->entry->decdat)
1747			break;/* The passphrase is OK. */
1748		if (retry > 10000) {
1749			/* Avoid infinity loop. */
1750			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1751			    "Too many incorrect passphrases");
1752			return (ARCHIVE_FAILED);
1753		}
1754	}
1755
1756	__archive_read_consume(a, ENC_HEADER_SIZE);
1757	zip->tctx_valid = 1;
1758	if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END)) {
1759	    zip->entry_bytes_remaining -= ENC_HEADER_SIZE;
1760	}
1761	/*zip->entry_uncompressed_bytes_read += ENC_HEADER_SIZE;*/
1762	zip->entry_compressed_bytes_read += ENC_HEADER_SIZE;
1763	zip->decrypted_bytes_remaining = 0;
1764
1765	return (zip_alloc_decryption_buffer(a));
1766#undef ENC_HEADER_SIZE
1767}
1768
1769static int
1770init_WinZip_AES_decryption(struct archive_read *a)
1771{
1772	struct zip *zip = (struct zip *)(a->format->data);
1773	const void *p;
1774	const uint8_t *pv;
1775	size_t key_len, salt_len;
1776	uint8_t derived_key[MAX_DERIVED_KEY_BUF_SIZE];
1777	int retry;
1778	int r;
1779
1780	if (zip->cctx_valid || zip->hctx_valid)
1781		return (ARCHIVE_OK);
1782
1783	switch (zip->entry->aes_extra.strength) {
1784	case 1: salt_len = 8;  key_len = 16; break;
1785	case 2: salt_len = 12; key_len = 24; break;
1786	case 3: salt_len = 16; key_len = 32; break;
1787	default: goto corrupted;
1788	}
1789	p = __archive_read_ahead(a, salt_len + 2, NULL);
1790	if (p == NULL)
1791		goto truncated;
1792
1793	for (retry = 0;; retry++) {
1794		const char *passphrase;
1795
1796		passphrase = __archive_read_next_passphrase(a);
1797		if (passphrase == NULL) {
1798			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1799			    (retry > 0)?
1800				"Incorrect passphrase":
1801				"Passphrase required for this entry");
1802			return (ARCHIVE_FAILED);
1803		}
1804		memset(derived_key, 0, sizeof(derived_key));
1805		r = archive_pbkdf2_sha1(passphrase, strlen(passphrase),
1806		    p, salt_len, 1000, derived_key, key_len * 2 + 2);
1807		if (r != 0) {
1808			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1809			    "Decryption is unsupported due to lack of "
1810			    "crypto library");
1811			return (ARCHIVE_FAILED);
1812		}
1813
1814		/* Check password verification value. */
1815		pv = ((const uint8_t *)p) + salt_len;
1816		if (derived_key[key_len * 2] == pv[0] &&
1817		    derived_key[key_len * 2 + 1] == pv[1])
1818			break;/* The passphrase is OK. */
1819		if (retry > 10000) {
1820			/* Avoid infinity loop. */
1821			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1822			    "Too many incorrect passphrases");
1823			return (ARCHIVE_FAILED);
1824		}
1825	}
1826
1827	r = archive_decrypto_aes_ctr_init(&zip->cctx, derived_key, key_len);
1828	if (r != 0) {
1829		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1830		    "Decryption is unsupported due to lack of crypto library");
1831		return (ARCHIVE_FAILED);
1832	}
1833	r = archive_hmac_sha1_init(&zip->hctx, derived_key + key_len, key_len);
1834	if (r != 0) {
1835		archive_decrypto_aes_ctr_release(&zip->cctx);
1836		archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1837		    "Failed to initialize HMAC-SHA1");
1838		return (ARCHIVE_FAILED);
1839	}
1840	zip->cctx_valid = zip->hctx_valid = 1;
1841	__archive_read_consume(a, salt_len + 2);
1842	zip->entry_bytes_remaining -= salt_len + 2 + AUTH_CODE_SIZE;
1843	if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END)
1844	    && zip->entry_bytes_remaining < 0)
1845		goto corrupted;
1846	zip->entry_compressed_bytes_read += salt_len + 2 + AUTH_CODE_SIZE;
1847	zip->decrypted_bytes_remaining = 0;
1848
1849	zip->entry->compression = zip->entry->aes_extra.compression;
1850	return (zip_alloc_decryption_buffer(a));
1851
1852truncated:
1853	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1854	    "Truncated ZIP file data");
1855	return (ARCHIVE_FATAL);
1856corrupted:
1857	archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1858	    "Corrupted ZIP file data");
1859	return (ARCHIVE_FATAL);
1860}
1861
1862static int
1863archive_read_format_zip_read_data(struct archive_read *a,
1864    const void **buff, size_t *size, int64_t *offset)
1865{
1866	int r;
1867	struct zip *zip = (struct zip *)(a->format->data);
1868
1869	if (zip->has_encrypted_entries ==
1870			ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW) {
1871		zip->has_encrypted_entries = 0;
1872	}
1873
1874	*offset = zip->entry_uncompressed_bytes_read;
1875	*size = 0;
1876	*buff = NULL;
1877
1878	/* If we hit end-of-entry last time, return ARCHIVE_EOF. */
1879	if (zip->end_of_entry)
1880		return (ARCHIVE_EOF);
1881
1882	/* Return EOF immediately if this is a non-regular file. */
1883	if (AE_IFREG != (zip->entry->mode & AE_IFMT))
1884		return (ARCHIVE_EOF);
1885
1886	__archive_read_consume(a, zip->unconsumed);
1887	zip->unconsumed = 0;
1888
1889	if (zip->init_decryption) {
1890		zip->has_encrypted_entries = 1;
1891		if (zip->entry->zip_flags & ZIP_STRONG_ENCRYPTED)
1892			r = read_decryption_header(a);
1893		else if (zip->entry->compression == WINZIP_AES_ENCRYPTION)
1894			r = init_WinZip_AES_decryption(a);
1895		else
1896			r = init_traditional_PKWARE_decryption(a);
1897		if (r != ARCHIVE_OK)
1898			return (r);
1899		zip->init_decryption = 0;
1900	}
1901
1902	switch(zip->entry->compression) {
1903	case 0:  /* No compression. */
1904		r =  zip_read_data_none(a, buff, size, offset);
1905		break;
1906#ifdef HAVE_ZLIB_H
1907	case 8: /* Deflate compression. */
1908		r =  zip_read_data_deflate(a, buff, size, offset);
1909		break;
1910#endif
1911	default: /* Unsupported compression. */
1912		/* Return a warning. */
1913		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
1914		    "Unsupported ZIP compression method (%s)",
1915		    compression_name(zip->entry->compression));
1916		/* We can't decompress this entry, but we will
1917		 * be able to skip() it and try the next entry. */
1918		return (ARCHIVE_FAILED);
1919		break;
1920	}
1921	if (r != ARCHIVE_OK)
1922		return (r);
1923	/* Update checksum */
1924	if (*size)
1925		zip->entry_crc32 = zip->crc32func(zip->entry_crc32, *buff,
1926		    (unsigned)*size);
1927	/* If we hit the end, swallow any end-of-data marker. */
1928	if (zip->end_of_entry) {
1929		/* Check file size, CRC against these values. */
1930		if (zip->entry->compressed_size !=
1931		    zip->entry_compressed_bytes_read) {
1932			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1933			    "ZIP compressed data is wrong size "
1934			    "(read %jd, expected %jd)",
1935			    (intmax_t)zip->entry_compressed_bytes_read,
1936			    (intmax_t)zip->entry->compressed_size);
1937			return (ARCHIVE_WARN);
1938		}
1939		/* Size field only stores the lower 32 bits of the actual
1940		 * size. */
1941		if ((zip->entry->uncompressed_size & UINT32_MAX)
1942		    != (zip->entry_uncompressed_bytes_read & UINT32_MAX)) {
1943			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1944			    "ZIP uncompressed data is wrong size "
1945			    "(read %jd, expected %jd)\n",
1946			    (intmax_t)zip->entry_uncompressed_bytes_read,
1947			    (intmax_t)zip->entry->uncompressed_size);
1948			return (ARCHIVE_WARN);
1949		}
1950		/* Check computed CRC against header */
1951		if ((!zip->hctx_valid ||
1952		      zip->entry->aes_extra.vendor != AES_VENDOR_AE_2) &&
1953		   zip->entry->crc32 != zip->entry_crc32
1954		    && !zip->ignore_crc32) {
1955			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
1956			    "ZIP bad CRC: 0x%lx should be 0x%lx",
1957			    (unsigned long)zip->entry_crc32,
1958			    (unsigned long)zip->entry->crc32);
1959			return (ARCHIVE_WARN);
1960		}
1961	}
1962
1963	return (ARCHIVE_OK);
1964}
1965
1966static int
1967archive_read_format_zip_cleanup(struct archive_read *a)
1968{
1969	struct zip *zip;
1970	struct zip_entry *zip_entry, *next_zip_entry;
1971
1972	zip = (struct zip *)(a->format->data);
1973#ifdef HAVE_ZLIB_H
1974	if (zip->stream_valid)
1975		inflateEnd(&zip->stream);
1976	free(zip->uncompressed_buffer);
1977#endif
1978	if (zip->zip_entries) {
1979		zip_entry = zip->zip_entries;
1980		while (zip_entry != NULL) {
1981			next_zip_entry = zip_entry->next;
1982			archive_string_free(&zip_entry->rsrcname);
1983			free(zip_entry);
1984			zip_entry = next_zip_entry;
1985		}
1986	}
1987	free(zip->decrypted_buffer);
1988	if (zip->cctx_valid)
1989		archive_decrypto_aes_ctr_release(&zip->cctx);
1990	if (zip->hctx_valid)
1991		archive_hmac_sha1_cleanup(&zip->hctx);
1992	free(zip->iv);
1993	free(zip->erd);
1994	free(zip->v_data);
1995	archive_string_free(&zip->format_name);
1996	free(zip);
1997	(a->format->data) = NULL;
1998	return (ARCHIVE_OK);
1999}
2000
2001static int
2002archive_read_format_zip_has_encrypted_entries(struct archive_read *_a)
2003{
2004	if (_a && _a->format) {
2005		struct zip * zip = (struct zip *)_a->format->data;
2006		if (zip) {
2007			return zip->has_encrypted_entries;
2008		}
2009	}
2010	return ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW;
2011}
2012
2013static int
2014archive_read_format_zip_options(struct archive_read *a,
2015    const char *key, const char *val)
2016{
2017	struct zip *zip;
2018	int ret = ARCHIVE_FAILED;
2019
2020	zip = (struct zip *)(a->format->data);
2021	if (strcmp(key, "compat-2x")  == 0) {
2022		/* Handle filenames as libarchive 2.x */
2023		zip->init_default_conversion = (val != NULL) ? 1 : 0;
2024		return (ARCHIVE_OK);
2025	} else if (strcmp(key, "hdrcharset")  == 0) {
2026		if (val == NULL || val[0] == 0)
2027			archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
2028			    "zip: hdrcharset option needs a character-set name"
2029			);
2030		else {
2031			zip->sconv = archive_string_conversion_from_charset(
2032			    &a->archive, val, 0);
2033			if (zip->sconv != NULL) {
2034				if (strcmp(val, "UTF-8") == 0)
2035					zip->sconv_utf8 = zip->sconv;
2036				ret = ARCHIVE_OK;
2037			} else
2038				ret = ARCHIVE_FATAL;
2039		}
2040		return (ret);
2041	} else if (strcmp(key, "ignorecrc32") == 0) {
2042		/* Mostly useful for testing. */
2043		if (val == NULL || val[0] == 0) {
2044			zip->crc32func = real_crc32;
2045			zip->ignore_crc32 = 0;
2046		} else {
2047			zip->crc32func = fake_crc32;
2048			zip->ignore_crc32 = 1;
2049		}
2050		return (ARCHIVE_OK);
2051	} else if (strcmp(key, "mac-ext") == 0) {
2052		zip->process_mac_extensions = (val != NULL && val[0] != 0);
2053		return (ARCHIVE_OK);
2054	}
2055
2056	/* Note: The "warn" return is just to inform the options
2057	 * supervisor that we didn't handle it.  It will generate
2058	 * a suitable error if no one used this option. */
2059	return (ARCHIVE_WARN);
2060}
2061
2062int
2063archive_read_support_format_zip(struct archive *a)
2064{
2065	int r;
2066	r = archive_read_support_format_zip_streamable(a);
2067	if (r != ARCHIVE_OK)
2068		return r;
2069	return (archive_read_support_format_zip_seekable(a));
2070}
2071
2072/* ------------------------------------------------------------------------ */
2073
2074/*
2075 * Streaming-mode support
2076 */
2077
2078
2079static int
2080archive_read_support_format_zip_capabilities_streamable(struct archive_read * a)
2081{
2082	(void)a; /* UNUSED */
2083	return (ARCHIVE_READ_FORMAT_CAPS_ENCRYPT_DATA |
2084		ARCHIVE_READ_FORMAT_CAPS_ENCRYPT_METADATA);
2085}
2086
2087static int
2088archive_read_format_zip_streamable_bid(struct archive_read *a, int best_bid)
2089{
2090	const char *p;
2091
2092	(void)best_bid; /* UNUSED */
2093
2094	if ((p = __archive_read_ahead(a, 4, NULL)) == NULL)
2095		return (-1);
2096
2097	/*
2098	 * Bid of 29 here comes from:
2099	 *  + 16 bits for "PK",
2100	 *  + next 16-bit field has 6 options so contributes
2101	 *    about 16 - log_2(6) ~= 16 - 2.6 ~= 13 bits
2102	 *
2103	 * So we've effectively verified ~29 total bits of check data.
2104	 */
2105	if (p[0] == 'P' && p[1] == 'K') {
2106		if ((p[2] == '\001' && p[3] == '\002')
2107		    || (p[2] == '\003' && p[3] == '\004')
2108		    || (p[2] == '\005' && p[3] == '\006')
2109		    || (p[2] == '\006' && p[3] == '\006')
2110		    || (p[2] == '\007' && p[3] == '\010')
2111		    || (p[2] == '0' && p[3] == '0'))
2112			return (29);
2113	}
2114
2115	/* TODO: It's worth looking ahead a little bit for a valid
2116	 * PK signature.  In particular, that would make it possible
2117	 * to read some UUEncoded SFX files or SFX files coming from
2118	 * a network socket. */
2119
2120	return (0);
2121}
2122
2123static int
2124archive_read_format_zip_streamable_read_header(struct archive_read *a,
2125    struct archive_entry *entry)
2126{
2127	struct zip *zip;
2128
2129	a->archive.archive_format = ARCHIVE_FORMAT_ZIP;
2130	if (a->archive.archive_format_name == NULL)
2131		a->archive.archive_format_name = "ZIP";
2132
2133	zip = (struct zip *)(a->format->data);
2134
2135	/*
2136	 * It should be sufficient to call archive_read_next_header() for
2137	 * a reader to determine if an entry is encrypted or not. If the
2138	 * encryption of an entry is only detectable when calling
2139	 * archive_read_data(), so be it. We'll do the same check there
2140	 * as well.
2141	 */
2142	if (zip->has_encrypted_entries ==
2143			ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW)
2144		zip->has_encrypted_entries = 0;
2145
2146	/* Make sure we have a zip_entry structure to use. */
2147	if (zip->zip_entries == NULL) {
2148		zip->zip_entries = malloc(sizeof(struct zip_entry));
2149		if (zip->zip_entries == NULL) {
2150			archive_set_error(&a->archive, ENOMEM,
2151			    "Out  of memory");
2152			return ARCHIVE_FATAL;
2153		}
2154	}
2155	zip->entry = zip->zip_entries;
2156	memset(zip->entry, 0, sizeof(struct zip_entry));
2157
2158	if (zip->cctx_valid)
2159		archive_decrypto_aes_ctr_release(&zip->cctx);
2160	if (zip->hctx_valid)
2161		archive_hmac_sha1_cleanup(&zip->hctx);
2162	zip->tctx_valid = zip->cctx_valid = zip->hctx_valid = 0;
2163	__archive_read_reset_passphrase(a);
2164
2165	/* Search ahead for the next local file header. */
2166	__archive_read_consume(a, zip->unconsumed);
2167	zip->unconsumed = 0;
2168	for (;;) {
2169		int64_t skipped = 0;
2170		const char *p, *end;
2171		ssize_t bytes;
2172
2173		p = __archive_read_ahead(a, 4, &bytes);
2174		if (p == NULL)
2175			return (ARCHIVE_FATAL);
2176		end = p + bytes;
2177
2178		while (p + 4 <= end) {
2179			if (p[0] == 'P' && p[1] == 'K') {
2180				if (p[2] == '\003' && p[3] == '\004') {
2181					/* Regular file entry. */
2182					__archive_read_consume(a, skipped);
2183					return zip_read_local_file_header(a,
2184					    entry, zip);
2185				}
2186
2187                              /*
2188                               * TODO: We cannot restore permissions
2189                               * based only on the local file headers.
2190                               * Consider scanning the central
2191                               * directory and returning additional
2192                               * entries for at least directories.
2193                               * This would allow us to properly set
2194                               * directory permissions.
2195			       *
2196			       * This won't help us fix symlinks
2197			       * and may not help with regular file
2198			       * permissions, either.  <sigh>
2199                               */
2200                              if (p[2] == '\001' && p[3] == '\002') {
2201                                      return (ARCHIVE_EOF);
2202                              }
2203
2204                              /* End of central directory?  Must be an
2205                               * empty archive. */
2206                              if ((p[2] == '\005' && p[3] == '\006')
2207                                  || (p[2] == '\006' && p[3] == '\006'))
2208                                      return (ARCHIVE_EOF);
2209			}
2210			++p;
2211			++skipped;
2212		}
2213		__archive_read_consume(a, skipped);
2214	}
2215}
2216
2217static int
2218archive_read_format_zip_read_data_skip_streamable(struct archive_read *a)
2219{
2220	struct zip *zip;
2221	int64_t bytes_skipped;
2222
2223	zip = (struct zip *)(a->format->data);
2224	bytes_skipped = __archive_read_consume(a, zip->unconsumed);
2225	zip->unconsumed = 0;
2226	if (bytes_skipped < 0)
2227		return (ARCHIVE_FATAL);
2228
2229	/* If we've already read to end of data, we're done. */
2230	if (zip->end_of_entry)
2231		return (ARCHIVE_OK);
2232
2233	/* So we know we're streaming... */
2234	if (0 == (zip->entry->zip_flags & ZIP_LENGTH_AT_END)
2235	    || zip->entry->compressed_size > 0) {
2236		/* We know the compressed length, so we can just skip. */
2237		bytes_skipped = __archive_read_consume(a,
2238					zip->entry_bytes_remaining);
2239		if (bytes_skipped < 0)
2240			return (ARCHIVE_FATAL);
2241		return (ARCHIVE_OK);
2242	}
2243
2244	if (zip->init_decryption) {
2245		int r;
2246
2247		zip->has_encrypted_entries = 1;
2248		if (zip->entry->zip_flags & ZIP_STRONG_ENCRYPTED)
2249			r = read_decryption_header(a);
2250		else if (zip->entry->compression == WINZIP_AES_ENCRYPTION)
2251			r = init_WinZip_AES_decryption(a);
2252		else
2253			r = init_traditional_PKWARE_decryption(a);
2254		if (r != ARCHIVE_OK)
2255			return (r);
2256		zip->init_decryption = 0;
2257	}
2258
2259	/* We're streaming and we don't know the length. */
2260	/* If the body is compressed and we know the format, we can
2261	 * find an exact end-of-entry by decompressing it. */
2262	switch (zip->entry->compression) {
2263#ifdef HAVE_ZLIB_H
2264	case 8: /* Deflate compression. */
2265		while (!zip->end_of_entry) {
2266			int64_t offset = 0;
2267			const void *buff = NULL;
2268			size_t size = 0;
2269			int r;
2270			r =  zip_read_data_deflate(a, &buff, &size, &offset);
2271			if (r != ARCHIVE_OK)
2272				return (r);
2273		}
2274		return ARCHIVE_OK;
2275#endif
2276	default: /* Uncompressed or unknown. */
2277		/* Scan for a PK\007\010 signature. */
2278		for (;;) {
2279			const char *p, *buff;
2280			ssize_t bytes_avail;
2281			buff = __archive_read_ahead(a, 16, &bytes_avail);
2282			if (bytes_avail < 16) {
2283				archive_set_error(&a->archive,
2284				    ARCHIVE_ERRNO_FILE_FORMAT,
2285				    "Truncated ZIP file data");
2286				return (ARCHIVE_FATAL);
2287			}
2288			p = buff;
2289			while (p <= buff + bytes_avail - 16) {
2290				if (p[3] == 'P') { p += 3; }
2291				else if (p[3] == 'K') { p += 2; }
2292				else if (p[3] == '\007') { p += 1; }
2293				else if (p[3] == '\010' && p[2] == '\007'
2294				    && p[1] == 'K' && p[0] == 'P') {
2295					if (zip->entry->flags & LA_USED_ZIP64)
2296						__archive_read_consume(a,
2297						    p - buff + 24);
2298					else
2299						__archive_read_consume(a,
2300						    p - buff + 16);
2301					return ARCHIVE_OK;
2302				} else { p += 4; }
2303			}
2304			__archive_read_consume(a, p - buff);
2305		}
2306	}
2307}
2308
2309int
2310archive_read_support_format_zip_streamable(struct archive *_a)
2311{
2312	struct archive_read *a = (struct archive_read *)_a;
2313	struct zip *zip;
2314	int r;
2315
2316	archive_check_magic(_a, ARCHIVE_READ_MAGIC,
2317	    ARCHIVE_STATE_NEW, "archive_read_support_format_zip");
2318
2319	zip = (struct zip *)calloc(1, sizeof(*zip));
2320	if (zip == NULL) {
2321		archive_set_error(&a->archive, ENOMEM,
2322		    "Can't allocate zip data");
2323		return (ARCHIVE_FATAL);
2324	}
2325
2326	/* Streamable reader doesn't support mac extensions. */
2327	zip->process_mac_extensions = 0;
2328
2329	/*
2330	 * Until enough data has been read, we cannot tell about
2331	 * any encrypted entries yet.
2332	 */
2333	zip->has_encrypted_entries = ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW;
2334	zip->crc32func = real_crc32;
2335
2336	r = __archive_read_register_format(a,
2337	    zip,
2338	    "zip",
2339	    archive_read_format_zip_streamable_bid,
2340	    archive_read_format_zip_options,
2341	    archive_read_format_zip_streamable_read_header,
2342	    archive_read_format_zip_read_data,
2343	    archive_read_format_zip_read_data_skip_streamable,
2344	    NULL,
2345	    archive_read_format_zip_cleanup,
2346	    archive_read_support_format_zip_capabilities_streamable,
2347	    archive_read_format_zip_has_encrypted_entries);
2348
2349	if (r != ARCHIVE_OK)
2350		free(zip);
2351	return (ARCHIVE_OK);
2352}
2353
2354/* ------------------------------------------------------------------------ */
2355
2356/*
2357 * Seeking-mode support
2358 */
2359
2360static int
2361archive_read_support_format_zip_capabilities_seekable(struct archive_read * a)
2362{
2363	(void)a; /* UNUSED */
2364	return (ARCHIVE_READ_FORMAT_CAPS_ENCRYPT_DATA |
2365		ARCHIVE_READ_FORMAT_CAPS_ENCRYPT_METADATA);
2366}
2367
2368/*
2369 * TODO: This is a performance sink because it forces the read core to
2370 * drop buffered data from the start of file, which will then have to
2371 * be re-read again if this bidder loses.
2372 *
2373 * We workaround this a little by passing in the best bid so far so
2374 * that later bidders can do nothing if they know they'll never
2375 * outbid.  But we can certainly do better...
2376 */
2377static int
2378read_eocd(struct zip *zip, const char *p, int64_t current_offset)
2379{
2380	/* Sanity-check the EOCD we've found. */
2381
2382	/* This must be the first volume. */
2383	if (archive_le16dec(p + 4) != 0)
2384		return 0;
2385	/* Central directory must be on this volume. */
2386	if (archive_le16dec(p + 4) != archive_le16dec(p + 6))
2387		return 0;
2388	/* All central directory entries must be on this volume. */
2389	if (archive_le16dec(p + 10) != archive_le16dec(p + 8))
2390		return 0;
2391	/* Central directory can't extend beyond start of EOCD record. */
2392	if (archive_le32dec(p + 16) + archive_le32dec(p + 12)
2393	    > current_offset)
2394		return 0;
2395
2396	/* Save the central directory location for later use. */
2397	zip->central_directory_offset = archive_le32dec(p + 16);
2398
2399	/* This is just a tiny bit higher than the maximum
2400	   returned by the streaming Zip bidder.  This ensures
2401	   that the more accurate seeking Zip parser wins
2402	   whenever seek is available. */
2403	return 32;
2404}
2405
2406/*
2407 * Examine Zip64 EOCD locator:  If it's valid, store the information
2408 * from it.
2409 */
2410static void
2411read_zip64_eocd(struct archive_read *a, struct zip *zip, const char *p)
2412{
2413	int64_t eocd64_offset;
2414	int64_t eocd64_size;
2415
2416	/* Sanity-check the locator record. */
2417
2418	/* Central dir must be on first volume. */
2419	if (archive_le32dec(p + 4) != 0)
2420		return;
2421	/* Must be only a single volume. */
2422	if (archive_le32dec(p + 16) != 1)
2423		return;
2424
2425	/* Find the Zip64 EOCD record. */
2426	eocd64_offset = archive_le64dec(p + 8);
2427	if (__archive_read_seek(a, eocd64_offset, SEEK_SET) < 0)
2428		return;
2429	if ((p = __archive_read_ahead(a, 56, NULL)) == NULL)
2430		return;
2431	/* Make sure we can read all of it. */
2432	eocd64_size = archive_le64dec(p + 4) + 12;
2433	if (eocd64_size < 56 || eocd64_size > 16384)
2434		return;
2435	if ((p = __archive_read_ahead(a, (size_t)eocd64_size, NULL)) == NULL)
2436		return;
2437
2438	/* Sanity-check the EOCD64 */
2439	if (archive_le32dec(p + 16) != 0) /* Must be disk #0 */
2440		return;
2441	if (archive_le32dec(p + 20) != 0) /* CD must be on disk #0 */
2442		return;
2443	/* CD can't be split. */
2444	if (archive_le64dec(p + 24) != archive_le64dec(p + 32))
2445		return;
2446
2447	/* Save the central directory offset for later use. */
2448	zip->central_directory_offset = archive_le64dec(p + 48);
2449}
2450
2451static int
2452archive_read_format_zip_seekable_bid(struct archive_read *a, int best_bid)
2453{
2454	struct zip *zip = (struct zip *)a->format->data;
2455	int64_t file_size, current_offset;
2456	const char *p;
2457	int i, tail;
2458
2459	/* If someone has already bid more than 32, then avoid
2460	   trashing the look-ahead buffers with a seek. */
2461	if (best_bid > 32)
2462		return (-1);
2463
2464	file_size = __archive_read_seek(a, 0, SEEK_END);
2465	if (file_size <= 0)
2466		return 0;
2467
2468	/* Search last 16k of file for end-of-central-directory
2469	 * record (which starts with PK\005\006) */
2470	tail = (int)zipmin(1024 * 16, file_size);
2471	current_offset = __archive_read_seek(a, -tail, SEEK_END);
2472	if (current_offset < 0)
2473		return 0;
2474	if ((p = __archive_read_ahead(a, (size_t)tail, NULL)) == NULL)
2475		return 0;
2476	/* Boyer-Moore search backwards from the end, since we want
2477	 * to match the last EOCD in the file (there can be more than
2478	 * one if there is an uncompressed Zip archive as a member
2479	 * within this Zip archive). */
2480	for (i = tail - 22; i > 0;) {
2481		switch (p[i]) {
2482		case 'P':
2483			if (memcmp(p + i, "PK\005\006", 4) == 0) {
2484				int ret = read_eocd(zip, p + i,
2485				    current_offset + i);
2486				if (ret > 0) {
2487					/* Zip64 EOCD locator precedes
2488					 * regular EOCD if present. */
2489					if (i >= 20
2490					    && memcmp(p + i - 20, "PK\006\007", 4) == 0) {
2491						read_zip64_eocd(a, zip, p + i - 20);
2492					}
2493					return (ret);
2494				}
2495			}
2496			i -= 4;
2497			break;
2498		case 'K': i -= 1; break;
2499		case 005: i -= 2; break;
2500		case 006: i -= 3; break;
2501		default: i -= 4; break;
2502		}
2503	}
2504	return 0;
2505}
2506
2507/* The red-black trees are only used in seeking mode to manage
2508 * the in-memory copy of the central directory. */
2509
2510static int
2511cmp_node(const struct archive_rb_node *n1, const struct archive_rb_node *n2)
2512{
2513	const struct zip_entry *e1 = (const struct zip_entry *)n1;
2514	const struct zip_entry *e2 = (const struct zip_entry *)n2;
2515
2516	if (e1->local_header_offset > e2->local_header_offset)
2517		return -1;
2518	if (e1->local_header_offset < e2->local_header_offset)
2519		return 1;
2520	return 0;
2521}
2522
2523static int
2524cmp_key(const struct archive_rb_node *n, const void *key)
2525{
2526	/* This function won't be called */
2527	(void)n; /* UNUSED */
2528	(void)key; /* UNUSED */
2529	return 1;
2530}
2531
2532static const struct archive_rb_tree_ops rb_ops = {
2533	&cmp_node, &cmp_key
2534};
2535
2536static int
2537rsrc_cmp_node(const struct archive_rb_node *n1,
2538    const struct archive_rb_node *n2)
2539{
2540	const struct zip_entry *e1 = (const struct zip_entry *)n1;
2541	const struct zip_entry *e2 = (const struct zip_entry *)n2;
2542
2543	return (strcmp(e2->rsrcname.s, e1->rsrcname.s));
2544}
2545
2546static int
2547rsrc_cmp_key(const struct archive_rb_node *n, const void *key)
2548{
2549	const struct zip_entry *e = (const struct zip_entry *)n;
2550	return (strcmp((const char *)key, e->rsrcname.s));
2551}
2552
2553static const struct archive_rb_tree_ops rb_rsrc_ops = {
2554	&rsrc_cmp_node, &rsrc_cmp_key
2555};
2556
2557static const char *
2558rsrc_basename(const char *name, size_t name_length)
2559{
2560	const char *s, *r;
2561
2562	r = s = name;
2563	for (;;) {
2564		s = memchr(s, '/', name_length - (s - name));
2565		if (s == NULL)
2566			break;
2567		r = ++s;
2568	}
2569	return (r);
2570}
2571
2572static void
2573expose_parent_dirs(struct zip *zip, const char *name, size_t name_length)
2574{
2575	struct archive_string str;
2576	struct zip_entry *dir;
2577	char *s;
2578
2579	archive_string_init(&str);
2580	archive_strncpy(&str, name, name_length);
2581	for (;;) {
2582		s = strrchr(str.s, '/');
2583		if (s == NULL)
2584			break;
2585		*s = '\0';
2586		/* Transfer the parent directory from zip->tree_rsrc RB
2587		 * tree to zip->tree RB tree to expose. */
2588		dir = (struct zip_entry *)
2589		    __archive_rb_tree_find_node(&zip->tree_rsrc, str.s);
2590		if (dir == NULL)
2591			break;
2592		__archive_rb_tree_remove_node(&zip->tree_rsrc, &dir->node);
2593		archive_string_free(&dir->rsrcname);
2594		__archive_rb_tree_insert_node(&zip->tree, &dir->node);
2595	}
2596	archive_string_free(&str);
2597}
2598
2599static int
2600slurp_central_directory(struct archive_read *a, struct zip *zip)
2601{
2602	ssize_t i;
2603	unsigned found;
2604	int64_t correction;
2605	ssize_t bytes_avail;
2606	const char *p;
2607
2608	/*
2609	 * Find the start of the central directory.  The end-of-CD
2610	 * record has our starting point, but there are lots of
2611	 * Zip archives which have had other data prepended to the
2612	 * file, which makes the recorded offsets all too small.
2613	 * So we search forward from the specified offset until we
2614	 * find the real start of the central directory.  Then we
2615	 * know the correction we need to apply to account for leading
2616	 * padding.
2617	 */
2618	if (__archive_read_seek(a, zip->central_directory_offset, SEEK_SET) < 0)
2619		return ARCHIVE_FATAL;
2620
2621	found = 0;
2622	while (!found) {
2623		if ((p = __archive_read_ahead(a, 20, &bytes_avail)) == NULL)
2624			return ARCHIVE_FATAL;
2625		for (found = 0, i = 0; !found && i < bytes_avail - 4;) {
2626			switch (p[i + 3]) {
2627			case 'P': i += 3; break;
2628			case 'K': i += 2; break;
2629			case 001: i += 1; break;
2630			case 002:
2631				if (memcmp(p + i, "PK\001\002", 4) == 0) {
2632					p += i;
2633					found = 1;
2634				} else
2635					i += 4;
2636				break;
2637			case 005: i += 1; break;
2638			case 006:
2639				if (memcmp(p + i, "PK\005\006", 4) == 0) {
2640					p += i;
2641					found = 1;
2642				} else if (memcmp(p + i, "PK\006\006", 4) == 0) {
2643					p += i;
2644					found = 1;
2645				} else
2646					i += 1;
2647				break;
2648			default: i += 4; break;
2649			}
2650		}
2651		__archive_read_consume(a, i);
2652	}
2653	correction = archive_filter_bytes(&a->archive, 0)
2654			- zip->central_directory_offset;
2655
2656	__archive_rb_tree_init(&zip->tree, &rb_ops);
2657	__archive_rb_tree_init(&zip->tree_rsrc, &rb_rsrc_ops);
2658
2659	zip->central_directory_entries_total = 0;
2660	while (1) {
2661		struct zip_entry *zip_entry;
2662		size_t filename_length, extra_length, comment_length;
2663		uint32_t external_attributes;
2664		const char *name, *r;
2665
2666		if ((p = __archive_read_ahead(a, 4, NULL)) == NULL)
2667			return ARCHIVE_FATAL;
2668		if (memcmp(p, "PK\006\006", 4) == 0
2669		    || memcmp(p, "PK\005\006", 4) == 0) {
2670			break;
2671		} else if (memcmp(p, "PK\001\002", 4) != 0) {
2672			archive_set_error(&a->archive,
2673			    -1, "Invalid central directory signature");
2674			return ARCHIVE_FATAL;
2675		}
2676		if ((p = __archive_read_ahead(a, 46, NULL)) == NULL)
2677			return ARCHIVE_FATAL;
2678
2679		zip_entry = calloc(1, sizeof(struct zip_entry));
2680		zip_entry->next = zip->zip_entries;
2681		zip_entry->flags |= LA_FROM_CENTRAL_DIRECTORY;
2682		zip->zip_entries = zip_entry;
2683		zip->central_directory_entries_total++;
2684
2685		/* version = p[4]; */
2686		zip_entry->system = p[5];
2687		/* version_required = archive_le16dec(p + 6); */
2688		zip_entry->zip_flags = archive_le16dec(p + 8);
2689		if (zip_entry->zip_flags
2690		      & (ZIP_ENCRYPTED | ZIP_STRONG_ENCRYPTED)){
2691			zip->has_encrypted_entries = 1;
2692		}
2693		zip_entry->compression = (char)archive_le16dec(p + 10);
2694		zip_entry->mtime = zip_time(p + 12);
2695		zip_entry->crc32 = archive_le32dec(p + 16);
2696		if (zip_entry->zip_flags & ZIP_LENGTH_AT_END)
2697			zip_entry->decdat = p[13];
2698		else
2699			zip_entry->decdat = p[19];
2700		zip_entry->compressed_size = archive_le32dec(p + 20);
2701		zip_entry->uncompressed_size = archive_le32dec(p + 24);
2702		filename_length = archive_le16dec(p + 28);
2703		extra_length = archive_le16dec(p + 30);
2704		comment_length = archive_le16dec(p + 32);
2705		/* disk_start = archive_le16dec(p + 34); */ /* Better be zero. */
2706		/* internal_attributes = archive_le16dec(p + 36); */ /* text bit */
2707		external_attributes = archive_le32dec(p + 38);
2708		zip_entry->local_header_offset =
2709		    archive_le32dec(p + 42) + correction;
2710
2711		/* If we can't guess the mode, leave it zero here;
2712		   when we read the local file header we might get
2713		   more information. */
2714		if (zip_entry->system == 3) {
2715			zip_entry->mode = external_attributes >> 16;
2716		} else if (zip_entry->system == 0) {
2717			// Interpret MSDOS directory bit
2718			if (0x10 == (external_attributes & 0x10)) {
2719				zip_entry->mode = AE_IFDIR | 0775;
2720			} else {
2721				zip_entry->mode = AE_IFREG | 0664;
2722			}
2723			if (0x01 == (external_attributes & 0x01)) {
2724				// Read-only bit; strip write permissions
2725				zip_entry->mode &= 0555;
2726			}
2727		} else {
2728			zip_entry->mode = 0;
2729		}
2730
2731		/* We're done with the regular data; get the filename and
2732		 * extra data. */
2733		__archive_read_consume(a, 46);
2734		p = __archive_read_ahead(a, filename_length + extra_length,
2735			NULL);
2736		if (p == NULL) {
2737			archive_set_error(&a->archive,
2738			    ARCHIVE_ERRNO_FILE_FORMAT,
2739			    "Truncated ZIP file header");
2740			return ARCHIVE_FATAL;
2741		}
2742		if (ARCHIVE_OK != process_extra(a, p + filename_length, extra_length, zip_entry)) {
2743			return ARCHIVE_FATAL;
2744		}
2745
2746		/*
2747		 * Mac resource fork files are stored under the
2748		 * "__MACOSX/" directory, so we should check if
2749		 * it is.
2750		 */
2751		if (!zip->process_mac_extensions) {
2752			/* Treat every entry as a regular entry. */
2753			__archive_rb_tree_insert_node(&zip->tree,
2754			    &zip_entry->node);
2755		} else {
2756			name = p;
2757			r = rsrc_basename(name, filename_length);
2758			if (filename_length >= 9 &&
2759			    strncmp("__MACOSX/", name, 9) == 0) {
2760				/* If this file is not a resource fork nor
2761				 * a directory. We should treat it as a non
2762				 * resource fork file to expose it. */
2763				if (name[filename_length-1] != '/' &&
2764				    (r - name < 3 || r[0] != '.' || r[1] != '_')) {
2765					__archive_rb_tree_insert_node(
2766					    &zip->tree, &zip_entry->node);
2767					/* Expose its parent directories. */
2768					expose_parent_dirs(zip, name,
2769					    filename_length);
2770				} else {
2771					/* This file is a resource fork file or
2772					 * a directory. */
2773					archive_strncpy(&(zip_entry->rsrcname),
2774					     name, filename_length);
2775					__archive_rb_tree_insert_node(
2776					    &zip->tree_rsrc, &zip_entry->node);
2777				}
2778			} else {
2779				/* Generate resource fork name to find its
2780				 * resource file at zip->tree_rsrc. */
2781				archive_strcpy(&(zip_entry->rsrcname),
2782				    "__MACOSX/");
2783				archive_strncat(&(zip_entry->rsrcname),
2784				    name, r - name);
2785				archive_strcat(&(zip_entry->rsrcname), "._");
2786				archive_strncat(&(zip_entry->rsrcname),
2787				    name + (r - name),
2788				    filename_length - (r - name));
2789				/* Register an entry to RB tree to sort it by
2790				 * file offset. */
2791				__archive_rb_tree_insert_node(&zip->tree,
2792				    &zip_entry->node);
2793			}
2794		}
2795
2796		/* Skip the comment too ... */
2797		__archive_read_consume(a,
2798		    filename_length + extra_length + comment_length);
2799	}
2800
2801	return ARCHIVE_OK;
2802}
2803
2804static ssize_t
2805zip_get_local_file_header_size(struct archive_read *a, size_t extra)
2806{
2807	const char *p;
2808	ssize_t filename_length, extra_length;
2809
2810	if ((p = __archive_read_ahead(a, extra + 30, NULL)) == NULL) {
2811		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2812		    "Truncated ZIP file header");
2813		return (ARCHIVE_WARN);
2814	}
2815	p += extra;
2816
2817	if (memcmp(p, "PK\003\004", 4) != 0) {
2818		archive_set_error(&a->archive, -1, "Damaged Zip archive");
2819		return ARCHIVE_WARN;
2820	}
2821	filename_length = archive_le16dec(p + 26);
2822	extra_length = archive_le16dec(p + 28);
2823
2824	return (30 + filename_length + extra_length);
2825}
2826
2827static int
2828zip_read_mac_metadata(struct archive_read *a, struct archive_entry *entry,
2829    struct zip_entry *rsrc)
2830{
2831	struct zip *zip = (struct zip *)a->format->data;
2832	unsigned char *metadata, *mp;
2833	int64_t offset = archive_filter_bytes(&a->archive, 0);
2834	size_t remaining_bytes, metadata_bytes;
2835	ssize_t hsize;
2836	int ret = ARCHIVE_OK, eof;
2837
2838	switch(rsrc->compression) {
2839	case 0:  /* No compression. */
2840		if (rsrc->uncompressed_size != rsrc->compressed_size) {
2841			archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2842			    "Malformed OS X metadata entry: inconsistent size");
2843			return (ARCHIVE_FATAL);
2844		}
2845#ifdef HAVE_ZLIB_H
2846	case 8: /* Deflate compression. */
2847#endif
2848		break;
2849	default: /* Unsupported compression. */
2850		/* Return a warning. */
2851		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2852		    "Unsupported ZIP compression method (%s)",
2853		    compression_name(rsrc->compression));
2854		/* We can't decompress this entry, but we will
2855		 * be able to skip() it and try the next entry. */
2856		return (ARCHIVE_WARN);
2857	}
2858
2859	if (rsrc->uncompressed_size > (4 * 1024 * 1024)) {
2860		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2861		    "Mac metadata is too large: %jd > 4M bytes",
2862		    (intmax_t)rsrc->uncompressed_size);
2863		return (ARCHIVE_WARN);
2864	}
2865	if (rsrc->compressed_size > (4 * 1024 * 1024)) {
2866		archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
2867		    "Mac metadata is too large: %jd > 4M bytes",
2868		    (intmax_t)rsrc->compressed_size);
2869		return (ARCHIVE_WARN);
2870	}
2871
2872	metadata = malloc((size_t)rsrc->uncompressed_size);
2873	if (metadata == NULL) {
2874		archive_set_error(&a->archive, ENOMEM,
2875		    "Can't allocate memory for Mac metadata");
2876		return (ARCHIVE_FATAL);
2877	}
2878
2879	if (offset < rsrc->local_header_offset)
2880		__archive_read_consume(a, rsrc->local_header_offset - offset);
2881	else if (offset != rsrc->local_header_offset) {
2882		__archive_read_seek(a, rsrc->local_header_offset, SEEK_SET);
2883	}
2884
2885	hsize = zip_get_local_file_header_size(a, 0);
2886	__archive_read_consume(a, hsize);
2887
2888	remaining_bytes = (size_t)rsrc->compressed_size;
2889	metadata_bytes = (size_t)rsrc->uncompressed_size;
2890	mp = metadata;
2891	eof = 0;
2892	while (!eof && remaining_bytes) {
2893		const unsigned char *p;
2894		ssize_t bytes_avail;
2895		size_t bytes_used;
2896
2897		p = __archive_read_ahead(a, 1, &bytes_avail);
2898		if (p == NULL) {
2899			archive_set_error(&a->archive,
2900			    ARCHIVE_ERRNO_FILE_FORMAT,
2901			    "Truncated ZIP file header");
2902			ret = ARCHIVE_WARN;
2903			goto exit_mac_metadata;
2904		}
2905		if ((size_t)bytes_avail > remaining_bytes)
2906			bytes_avail = remaining_bytes;
2907		switch(rsrc->compression) {
2908		case 0:  /* No compression. */
2909			if ((size_t)bytes_avail > metadata_bytes)
2910				bytes_avail = metadata_bytes;
2911			memcpy(mp, p, bytes_avail);
2912			bytes_used = (size_t)bytes_avail;
2913			metadata_bytes -= bytes_used;
2914			mp += bytes_used;
2915			if (metadata_bytes == 0)
2916				eof = 1;
2917			break;
2918#ifdef HAVE_ZLIB_H
2919		case 8: /* Deflate compression. */
2920		{
2921			int r;
2922
2923			ret = zip_deflate_init(a, zip);
2924			if (ret != ARCHIVE_OK)
2925				goto exit_mac_metadata;
2926			zip->stream.next_in =
2927			    (Bytef *)(uintptr_t)(const void *)p;
2928			zip->stream.avail_in = (uInt)bytes_avail;
2929			zip->stream.total_in = 0;
2930			zip->stream.next_out = mp;
2931			zip->stream.avail_out = (uInt)metadata_bytes;
2932			zip->stream.total_out = 0;
2933
2934			r = inflate(&zip->stream, 0);
2935			switch (r) {
2936			case Z_OK:
2937				break;
2938			case Z_STREAM_END:
2939				eof = 1;
2940				break;
2941			case Z_MEM_ERROR:
2942				archive_set_error(&a->archive, ENOMEM,
2943				    "Out of memory for ZIP decompression");
2944				ret = ARCHIVE_FATAL;
2945				goto exit_mac_metadata;
2946			default:
2947				archive_set_error(&a->archive,
2948				    ARCHIVE_ERRNO_MISC,
2949				    "ZIP decompression failed (%d)", r);
2950				ret = ARCHIVE_FATAL;
2951				goto exit_mac_metadata;
2952			}
2953			bytes_used = zip->stream.total_in;
2954			metadata_bytes -= zip->stream.total_out;
2955			mp += zip->stream.total_out;
2956			break;
2957		}
2958#endif
2959		default:
2960			bytes_used = 0;
2961			break;
2962		}
2963		__archive_read_consume(a, bytes_used);
2964		remaining_bytes -= bytes_used;
2965	}
2966	archive_entry_copy_mac_metadata(entry, metadata,
2967	    (size_t)rsrc->uncompressed_size - metadata_bytes);
2968
2969exit_mac_metadata:
2970	__archive_read_seek(a, offset, SEEK_SET);
2971	zip->decompress_init = 0;
2972	free(metadata);
2973	return (ret);
2974}
2975
2976static int
2977archive_read_format_zip_seekable_read_header(struct archive_read *a,
2978	struct archive_entry *entry)
2979{
2980	struct zip *zip = (struct zip *)a->format->data;
2981	struct zip_entry *rsrc;
2982	int64_t offset;
2983	int r, ret = ARCHIVE_OK;
2984
2985	/*
2986	 * It should be sufficient to call archive_read_next_header() for
2987	 * a reader to determine if an entry is encrypted or not. If the
2988	 * encryption of an entry is only detectable when calling
2989	 * archive_read_data(), so be it. We'll do the same check there
2990	 * as well.
2991	 */
2992	if (zip->has_encrypted_entries ==
2993			ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW)
2994		zip->has_encrypted_entries = 0;
2995
2996	a->archive.archive_format = ARCHIVE_FORMAT_ZIP;
2997	if (a->archive.archive_format_name == NULL)
2998		a->archive.archive_format_name = "ZIP";
2999
3000	if (zip->zip_entries == NULL) {
3001		r = slurp_central_directory(a, zip);
3002		if (r != ARCHIVE_OK)
3003			return r;
3004		/* Get first entry whose local header offset is lower than
3005		 * other entries in the archive file. */
3006		zip->entry =
3007		    (struct zip_entry *)ARCHIVE_RB_TREE_MIN(&zip->tree);
3008	} else if (zip->entry != NULL) {
3009		/* Get next entry in local header offset order. */
3010		zip->entry = (struct zip_entry *)__archive_rb_tree_iterate(
3011		    &zip->tree, &zip->entry->node, ARCHIVE_RB_DIR_RIGHT);
3012	}
3013
3014	if (zip->entry == NULL)
3015		return ARCHIVE_EOF;
3016
3017	if (zip->entry->rsrcname.s)
3018		rsrc = (struct zip_entry *)__archive_rb_tree_find_node(
3019		    &zip->tree_rsrc, zip->entry->rsrcname.s);
3020	else
3021		rsrc = NULL;
3022
3023	if (zip->cctx_valid)
3024		archive_decrypto_aes_ctr_release(&zip->cctx);
3025	if (zip->hctx_valid)
3026		archive_hmac_sha1_cleanup(&zip->hctx);
3027	zip->tctx_valid = zip->cctx_valid = zip->hctx_valid = 0;
3028	__archive_read_reset_passphrase(a);
3029
3030	/* File entries are sorted by the header offset, we should mostly
3031	 * use __archive_read_consume to advance a read point to avoid redundant
3032	 * data reading.  */
3033	offset = archive_filter_bytes(&a->archive, 0);
3034	if (offset < zip->entry->local_header_offset)
3035		__archive_read_consume(a,
3036		    zip->entry->local_header_offset - offset);
3037	else if (offset != zip->entry->local_header_offset) {
3038		__archive_read_seek(a, zip->entry->local_header_offset,
3039		    SEEK_SET);
3040	}
3041	zip->unconsumed = 0;
3042	r = zip_read_local_file_header(a, entry, zip);
3043	if (r != ARCHIVE_OK)
3044		return r;
3045	if (rsrc) {
3046		int ret2 = zip_read_mac_metadata(a, entry, rsrc);
3047		if (ret2 < ret)
3048			ret = ret2;
3049	}
3050	return (ret);
3051}
3052
3053/*
3054 * We're going to seek for the next header anyway, so we don't
3055 * need to bother doing anything here.
3056 */
3057static int
3058archive_read_format_zip_read_data_skip_seekable(struct archive_read *a)
3059{
3060	struct zip *zip;
3061	zip = (struct zip *)(a->format->data);
3062
3063	zip->unconsumed = 0;
3064	return (ARCHIVE_OK);
3065}
3066
3067int
3068archive_read_support_format_zip_seekable(struct archive *_a)
3069{
3070	struct archive_read *a = (struct archive_read *)_a;
3071	struct zip *zip;
3072	int r;
3073
3074	archive_check_magic(_a, ARCHIVE_READ_MAGIC,
3075	    ARCHIVE_STATE_NEW, "archive_read_support_format_zip_seekable");
3076
3077	zip = (struct zip *)calloc(1, sizeof(*zip));
3078	if (zip == NULL) {
3079		archive_set_error(&a->archive, ENOMEM,
3080		    "Can't allocate zip data");
3081		return (ARCHIVE_FATAL);
3082	}
3083
3084#ifdef HAVE_COPYFILE_H
3085	/* Set this by default on Mac OS. */
3086	zip->process_mac_extensions = 1;
3087#endif
3088
3089	/*
3090	 * Until enough data has been read, we cannot tell about
3091	 * any encrypted entries yet.
3092	 */
3093	zip->has_encrypted_entries = ARCHIVE_READ_FORMAT_ENCRYPTION_DONT_KNOW;
3094	zip->crc32func = real_crc32;
3095
3096	r = __archive_read_register_format(a,
3097	    zip,
3098	    "zip",
3099	    archive_read_format_zip_seekable_bid,
3100	    archive_read_format_zip_options,
3101	    archive_read_format_zip_seekable_read_header,
3102	    archive_read_format_zip_read_data,
3103	    archive_read_format_zip_read_data_skip_seekable,
3104	    NULL,
3105	    archive_read_format_zip_cleanup,
3106	    archive_read_support_format_zip_capabilities_seekable,
3107	    archive_read_format_zip_has_encrypted_entries);
3108
3109	if (r != ARCHIVE_OK)
3110		free(zip);
3111	return (ARCHIVE_OK);
3112}
3113