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-rw-r--r--src/Common/libzip/zip_open.c853
1 files changed, 853 insertions, 0 deletions
diff --git a/src/Common/libzip/zip_open.c b/src/Common/libzip/zip_open.c
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--- /dev/null
+++ b/src/Common/libzip/zip_open.c
@@ -0,0 +1,853 @@
+/*
+ zip_open.c -- open zip archive by name
+ Copyright (C) 1999-2015 Dieter Baron and Thomas Klausner
+
+ This file is part of libzip, a library to manipulate ZIP archives.
+ The authors can be contacted at <libzip@nih.at>
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+ 1. Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+ 3. The names of the authors may not be used to endorse or promote
+ products derived from this software without specific prior
+ written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
+ OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
+ DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+ GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+ IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+#include <sys/stat.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "zipint.h"
+
+typedef enum {
+ EXISTS_ERROR = -1,
+ EXISTS_NOT = 0,
+ EXISTS_EMPTY,
+ EXISTS_NONEMPTY,
+} exists_t;
+static zip_t *_zip_allocate_new(zip_source_t *src, unsigned int flags, zip_error_t *error);
+static zip_int64_t _zip_checkcons(zip_t *za, zip_cdir_t *cdir, zip_error_t *error);
+static zip_cdir_t *_zip_find_central_dir(zip_t *za, zip_uint64_t len);
+static exists_t _zip_file_exists(zip_source_t *src, zip_error_t *error);
+static int _zip_headercomp(const zip_dirent_t *, const zip_dirent_t *);
+static unsigned char *_zip_memmem(const unsigned char *, size_t, const unsigned char *, size_t);
+static zip_cdir_t *_zip_read_cdir(zip_t *za, zip_buffer_t *buffer, zip_uint64_t buf_offset, zip_error_t *error);
+static zip_cdir_t *_zip_read_eocd(zip_buffer_t *buffer, zip_uint64_t buf_offset, unsigned int flags, zip_error_t *error);
+static zip_cdir_t *_zip_read_eocd64(zip_source_t *src, zip_buffer_t *buffer, zip_uint64_t buf_offset, unsigned int flags, zip_error_t *error);
+
+
+ZIP_EXTERN zip_t *
+zip_open(const char *fn, int _flags, int *zep)
+{
+ zip_t *za;
+ zip_source_t *src;
+ struct zip_error error;
+
+ zip_error_init(&error);
+ if ((src = zip_source_file_create(fn, 0, -1, &error)) == NULL) {
+ _zip_set_open_error(zep, &error, 0);
+ zip_error_fini(&error);
+ return NULL;
+ }
+
+ if ((za = zip_open_from_source(src, _flags, &error)) == NULL) {
+ zip_source_free(src);
+ _zip_set_open_error(zep, &error, 0);
+ zip_error_fini(&error);
+ return NULL;
+ }
+
+ zip_error_fini(&error);
+ return za;
+}
+
+
+ZIP_EXTERN zip_t *
+zip_open_from_source(zip_source_t *src, int _flags, zip_error_t *error)
+{
+ static zip_int64_t needed_support_read = -1;
+ static zip_int64_t needed_support_write = -1;
+
+ unsigned int flags;
+ zip_int64_t supported;
+ exists_t exists;
+
+ if (_flags < 0 || src == NULL) {
+ zip_error_set(error, ZIP_ER_INVAL, 0);
+ return NULL;
+ }
+ flags = (unsigned int)_flags;
+
+ supported = zip_source_supports(src);
+ if (needed_support_read == -1) {
+ needed_support_read = zip_source_make_command_bitmap(ZIP_SOURCE_OPEN, ZIP_SOURCE_READ, ZIP_SOURCE_CLOSE, ZIP_SOURCE_SEEK, ZIP_SOURCE_TELL, ZIP_SOURCE_STAT, -1);
+ needed_support_write = zip_source_make_command_bitmap(ZIP_SOURCE_BEGIN_WRITE, ZIP_SOURCE_COMMIT_WRITE, ZIP_SOURCE_ROLLBACK_WRITE, ZIP_SOURCE_SEEK_WRITE, ZIP_SOURCE_TELL_WRITE, ZIP_SOURCE_REMOVE, -1);
+ }
+ if ((supported & needed_support_read) != needed_support_read) {
+ zip_error_set(error, ZIP_ER_OPNOTSUPP, 0);
+ return NULL;
+ }
+ if ((supported & needed_support_write) != needed_support_write) {
+ flags |= ZIP_RDONLY;
+ }
+
+ if ((flags & (ZIP_RDONLY|ZIP_TRUNCATE)) == (ZIP_RDONLY|ZIP_TRUNCATE)) {
+ zip_error_set(error, ZIP_ER_RDONLY, 0);
+ return NULL;
+ }
+
+ exists = _zip_file_exists(src, error);
+ switch (exists) {
+ case EXISTS_ERROR:
+ return NULL;
+
+ case EXISTS_NOT:
+ if ((flags & ZIP_CREATE) == 0) {
+ zip_error_set(error, ZIP_ER_NOENT, 0);
+ return NULL;
+ }
+ return _zip_allocate_new(src, flags, error);
+
+ default: {
+ zip_t *za;
+ if (flags & ZIP_EXCL) {
+ zip_error_set(error, ZIP_ER_EXISTS, 0);
+ return NULL;
+ }
+ if (zip_source_open(src) < 0) {
+ _zip_error_set_from_source(error, src);
+ return NULL;
+ }
+
+ if (flags & ZIP_TRUNCATE) {
+ za = _zip_allocate_new(src, flags, error);
+ }
+ else {
+ /* ZIP_CREATE gets ignored if file exists and not ZIP_EXCL, just like open() */
+ za = _zip_open(src, flags, error);
+ }
+
+ if (za == NULL) {
+ zip_source_close(src);
+ return NULL;
+ }
+ return za;
+ }
+ }
+}
+
+ZIP_EXTERN int
+zip_archive_set_tempdir(zip_t *za, const char *tempdir)
+{
+ char *new_tempdir;
+
+ if (tempdir) {
+ if ((new_tempdir = strdup(tempdir)) == NULL) {
+ zip_error_set(&za->error, ZIP_ER_MEMORY, errno);
+ return -1;
+ }
+ }
+ else
+ new_tempdir = NULL;
+
+ free(za->tempdir);
+ za->tempdir = new_tempdir;
+
+ return 0;
+}
+
+zip_t *
+_zip_open(zip_source_t *src, unsigned int flags, zip_error_t *error)
+{
+ zip_t *za;
+ zip_cdir_t *cdir;
+ struct zip_stat st;
+ zip_uint64_t len, idx;
+
+ zip_stat_init(&st);
+ if (zip_source_stat(src, &st) < 0) {
+ _zip_error_set_from_source(error, src);
+ return NULL;
+ }
+ if ((st.valid & ZIP_STAT_SIZE) == 0) {
+ zip_error_set(error, ZIP_ER_SEEK, EOPNOTSUPP);
+ return NULL;
+ }
+ len = st.size;
+
+ /* treat empty files as empty archives */
+ if (len == 0) {
+ if ((za=_zip_allocate_new(src, flags, error)) == NULL) {
+ zip_source_free(src);
+ return NULL;
+ }
+
+ return za;
+ }
+
+ if ((za=_zip_allocate_new(src, flags, error)) == NULL) {
+ return NULL;
+ }
+
+ if ((cdir = _zip_find_central_dir(za, len)) == NULL) {
+ _zip_error_copy(error, &za->error);
+ /* keep src so discard does not get rid of it */
+ zip_source_keep(src);
+ zip_discard(za);
+ return NULL;
+ }
+
+ za->entry = cdir->entry;
+ za->nentry = cdir->nentry;
+ za->nentry_alloc = cdir->nentry_alloc;
+ za->comment_orig = cdir->comment;
+
+ free(cdir);
+
+ for (idx = 0; idx < za->nentry; idx++) {
+ const zip_uint8_t *name = _zip_string_get(za->entry[idx].orig->filename, NULL, 0, error);
+ if (name == NULL) {
+ /* keep src so discard does not get rid of it */
+ zip_source_keep(src);
+ zip_discard(za);
+ return NULL;
+ }
+
+ if (_zip_hash_add(za->names, name, idx, ZIP_FL_UNCHANGED, &za->error) == false) {
+ if (za->error.zip_err != ZIP_ER_EXISTS || (flags & ZIP_CHECKCONS)) {
+ _zip_error_copy(error, &za->error);
+ /* keep src so discard does not get rid of it */
+ zip_source_keep(src);
+ zip_discard(za);
+ return NULL;
+ }
+ }
+ }
+
+ za->ch_flags = za->flags;
+
+ return za;
+}
+
+
+void
+_zip_set_open_error(int *zep, const zip_error_t *err, int ze)
+{
+ if (err) {
+ ze = zip_error_code_zip(err);
+ if (zip_error_system_type(err) == ZIP_ET_SYS) {
+ errno = zip_error_code_system(err);
+ }
+ }
+
+ if (zep)
+ *zep = ze;
+}
+
+
+/* _zip_readcdir:
+ tries to find a valid end-of-central-directory at the beginning of
+ buf, and then the corresponding central directory entries.
+ Returns a struct zip_cdir which contains the central directory
+ entries, or NULL if unsuccessful. */
+
+static zip_cdir_t *
+_zip_read_cdir(zip_t *za, zip_buffer_t *buffer, zip_uint64_t buf_offset, zip_error_t *error)
+{
+ zip_cdir_t *cd;
+ zip_uint16_t comment_len;
+ zip_uint64_t i, left;
+ zip_uint64_t eocd_offset = _zip_buffer_offset(buffer);
+ zip_buffer_t *cd_buffer;
+
+ if (_zip_buffer_left(buffer) < EOCDLEN) {
+ /* not enough bytes left for comment */
+ zip_error_set(error, ZIP_ER_NOZIP, 0);
+ return NULL;
+ }
+
+ /* check for end-of-central-dir magic */
+ if (memcmp(_zip_buffer_get(buffer, 4), EOCD_MAGIC, 4) != 0) {
+ zip_error_set(error, ZIP_ER_NOZIP, 0);
+ return NULL;
+ }
+
+ if (eocd_offset >= EOCD64LOCLEN && memcmp(_zip_buffer_data(buffer) + eocd_offset - EOCD64LOCLEN, EOCD64LOC_MAGIC, 4) == 0) {
+ _zip_buffer_set_offset(buffer, eocd_offset - EOCD64LOCLEN);
+ cd = _zip_read_eocd64(za->src, buffer, buf_offset, za->flags, error);
+ }
+ else {
+ _zip_buffer_set_offset(buffer, eocd_offset);
+ cd = _zip_read_eocd(buffer, buf_offset, za->flags, error);
+ }
+
+ if (cd == NULL)
+ return NULL;
+
+ _zip_buffer_set_offset(buffer, eocd_offset + 20);
+ comment_len = _zip_buffer_get_16(buffer);
+
+ if (cd->offset + cd->size > buf_offset + eocd_offset) {
+ /* cdir spans past EOCD record */
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ _zip_cdir_free(cd);
+ return NULL;
+ }
+
+ if (comment_len || (za->open_flags & ZIP_CHECKCONS)) {
+ zip_uint64_t tail_len;
+
+ _zip_buffer_set_offset(buffer, eocd_offset + EOCDLEN);
+ tail_len = _zip_buffer_left(buffer);
+
+ if (tail_len < comment_len || ((za->open_flags & ZIP_CHECKCONS) && tail_len != comment_len)) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ _zip_cdir_free(cd);
+ return NULL;
+ }
+
+ if (comment_len) {
+ if ((cd->comment=_zip_string_new(_zip_buffer_get(buffer, comment_len), comment_len, ZIP_FL_ENC_GUESS, error)) == NULL) {
+ _zip_cdir_free(cd);
+ return NULL;
+ }
+ }
+ }
+
+ if (cd->offset >= buf_offset) {
+ zip_uint8_t *data;
+ /* if buffer already read in, use it */
+ _zip_buffer_set_offset(buffer, cd->offset - buf_offset);
+
+ if ((data = _zip_buffer_get(buffer, cd->size)) == NULL) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ _zip_cdir_free(cd);
+ return NULL;
+ }
+ if ((cd_buffer = _zip_buffer_new(data, cd->size)) == NULL) {
+ zip_error_set(error, ZIP_ER_MEMORY, 0);
+ _zip_cdir_free(cd);
+ return NULL;
+ }
+ }
+ else {
+ cd_buffer = NULL;
+
+ if (zip_source_seek(za->src, (zip_int64_t)cd->offset, SEEK_SET) < 0) {
+ _zip_error_set_from_source(error, za->src);
+ _zip_cdir_free(cd);
+ return NULL;
+ }
+
+ /* possible consistency check: cd->offset = len-(cd->size+cd->comment_len+EOCDLEN) ? */
+ if (zip_source_tell(za->src) != (zip_int64_t)cd->offset) {
+ zip_error_set(error, ZIP_ER_NOZIP, 0);
+ _zip_cdir_free(cd);
+ return NULL;
+ }
+ }
+
+ left = (zip_uint64_t)cd->size;
+ i=0;
+ while (i<cd->nentry && left > 0) {
+ zip_int64_t entry_size;
+ if ((cd->entry[i].orig=_zip_dirent_new()) == NULL || (entry_size = _zip_dirent_read(cd->entry[i].orig, za->src, cd_buffer, false, error)) < 0) {
+ _zip_cdir_free(cd);
+ _zip_buffer_free(cd_buffer);
+ return NULL;
+ }
+ i++;
+ left -= (zip_uint64_t)entry_size;
+ }
+
+ if (i != cd->nentry) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ _zip_buffer_free(cd_buffer);
+ _zip_cdir_free(cd);
+ return NULL;
+ }
+
+ if (za->open_flags & ZIP_CHECKCONS) {
+ bool ok;
+
+ if (cd_buffer) {
+ ok = _zip_buffer_eof(cd_buffer);
+ }
+ else {
+ zip_int64_t offset = zip_source_tell(za->src);
+
+ if (offset < 0) {
+ _zip_error_set_from_source(error, za->src);
+ _zip_buffer_free(cd_buffer);
+ _zip_cdir_free(cd);
+ return NULL;
+ }
+ ok = ((zip_uint64_t)offset == cd->offset + cd->size);
+ }
+
+ if (!ok) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ _zip_buffer_free(cd_buffer);
+ _zip_cdir_free(cd);
+ return NULL;
+ }
+ }
+
+ _zip_buffer_free(cd_buffer);
+ return cd;
+}
+
+
+/* _zip_checkcons:
+ Checks the consistency of the central directory by comparing central
+ directory entries with local headers and checking for plausible
+ file and header offsets. Returns -1 if not plausible, else the
+ difference between the lowest and the highest fileposition reached */
+
+static zip_int64_t
+_zip_checkcons(zip_t *za, zip_cdir_t *cd, zip_error_t *error)
+{
+ zip_uint64_t i;
+ zip_uint64_t min, max, j;
+ struct zip_dirent temp;
+
+ _zip_dirent_init(&temp);
+ if (cd->nentry) {
+ max = cd->entry[0].orig->offset;
+ min = cd->entry[0].orig->offset;
+ }
+ else
+ min = max = 0;
+
+ for (i=0; i<cd->nentry; i++) {
+ if (cd->entry[i].orig->offset < min)
+ min = cd->entry[i].orig->offset;
+ if (min > (zip_uint64_t)cd->offset) {
+ zip_error_set(error, ZIP_ER_NOZIP, 0);
+ return -1;
+ }
+
+ j = cd->entry[i].orig->offset + cd->entry[i].orig->comp_size
+ + _zip_string_length(cd->entry[i].orig->filename) + LENTRYSIZE;
+ if (j > max)
+ max = j;
+ if (max > (zip_uint64_t)cd->offset) {
+ zip_error_set(error, ZIP_ER_NOZIP, 0);
+ return -1;
+ }
+
+ if (zip_source_seek(za->src, (zip_int64_t)cd->entry[i].orig->offset, SEEK_SET) < 0) {
+ _zip_error_set_from_source(error, za->src);
+ return -1;
+ }
+
+ if (_zip_dirent_read(&temp, za->src, NULL, true, error) == -1) {
+ _zip_dirent_finalize(&temp);
+ return -1;
+ }
+
+ if (_zip_headercomp(cd->entry[i].orig, &temp) != 0) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ _zip_dirent_finalize(&temp);
+ return -1;
+ }
+
+ cd->entry[i].orig->extra_fields = _zip_ef_merge(cd->entry[i].orig->extra_fields, temp.extra_fields);
+ cd->entry[i].orig->local_extra_fields_read = 1;
+ temp.extra_fields = NULL;
+
+ _zip_dirent_finalize(&temp);
+ }
+
+ return (max-min) < ZIP_INT64_MAX ? (zip_int64_t)(max-min) : ZIP_INT64_MAX;
+}
+
+
+/* _zip_headercomp:
+ compares a central directory entry and a local file header
+ Return 0 if they are consistent, -1 if not. */
+
+static int
+_zip_headercomp(const zip_dirent_t *central, const zip_dirent_t *local)
+{
+ if ((central->version_needed != local->version_needed)
+#if 0
+ /* some zip-files have different values in local
+ and global headers for the bitflags */
+ || (central->bitflags != local->bitflags)
+#endif
+ || (central->comp_method != local->comp_method)
+ || (central->last_mod != local->last_mod)
+ || !_zip_string_equal(central->filename, local->filename))
+ return -1;
+
+ if ((central->crc != local->crc) || (central->comp_size != local->comp_size)
+ || (central->uncomp_size != local->uncomp_size)) {
+ /* InfoZip stores valid values in local header even when data descriptor is used.
+ This is in violation of the appnote. */
+ if (((local->bitflags & ZIP_GPBF_DATA_DESCRIPTOR) == 0
+ || local->crc != 0 || local->comp_size != 0 || local->uncomp_size != 0))
+ return -1;
+ }
+
+ return 0;
+}
+
+
+static zip_t *
+_zip_allocate_new(zip_source_t *src, unsigned int flags, zip_error_t *error)
+{
+ zip_t *za;
+
+ if ((za = _zip_new(error)) == NULL) {
+ return NULL;
+ }
+
+ za->src = src;
+ za->open_flags = flags;
+ if (flags & ZIP_RDONLY) {
+ za->flags |= ZIP_AFL_RDONLY;
+ za->ch_flags |= ZIP_AFL_RDONLY;
+ }
+ return za;
+}
+
+
+/*
+ * tests for file existence
+ */
+static exists_t
+_zip_file_exists(zip_source_t *src, zip_error_t *error)
+{
+ struct zip_stat st;
+
+ zip_stat_init(&st);
+ if (zip_source_stat(src, &st) != 0) {
+ zip_error_t *src_error = zip_source_error(src);
+ if (zip_error_code_zip(src_error) == ZIP_ER_READ && zip_error_code_system(src_error) == ENOENT) {
+ return EXISTS_NOT;
+ }
+ _zip_error_copy(error, src_error);
+ return EXISTS_ERROR;
+ }
+
+ return (st.valid & ZIP_STAT_SIZE) && st.size == 0 ? EXISTS_EMPTY : EXISTS_NONEMPTY;
+}
+
+
+static zip_cdir_t *
+_zip_find_central_dir(zip_t *za, zip_uint64_t len)
+{
+ zip_cdir_t *cdir, *cdirnew;
+ zip_uint8_t *match;
+ zip_int64_t buf_offset;
+ zip_uint64_t buflen;
+ zip_int64_t a;
+ zip_int64_t best;
+ zip_error_t error;
+ zip_buffer_t *buffer;
+
+ if (len < EOCDLEN) {
+ zip_error_set(&za->error, ZIP_ER_NOZIP, 0);
+ return NULL;
+ }
+
+ buflen = (len < CDBUFSIZE ? len : CDBUFSIZE);
+ if (zip_source_seek(za->src, -(zip_int64_t)buflen, SEEK_END) < 0) {
+ zip_error_t *src_error = zip_source_error(za->src);
+ if (zip_error_code_zip(src_error) != ZIP_ER_SEEK || zip_error_code_system(src_error) != EFBIG) {
+ /* seek before start of file on my machine */
+ _zip_error_copy(&za->error, src_error);
+ return NULL;
+ }
+ }
+ if ((buf_offset = zip_source_tell(za->src)) < 0) {
+ _zip_error_set_from_source(&za->error, za->src);
+ return NULL;
+ }
+
+ if ((buffer = _zip_buffer_new_from_source(za->src, buflen, NULL, &za->error)) == NULL) {
+ return NULL;
+ }
+
+ best = -1;
+ cdir = NULL;
+ if (buflen >= CDBUFSIZE) {
+ /* EOCD64 locator is before EOCD, so leave place for it */
+ _zip_buffer_set_offset(buffer, EOCD64LOCLEN);
+ }
+ zip_error_set(&error, ZIP_ER_NOZIP, 0);
+
+ match = _zip_buffer_get(buffer, 0);
+ while ((match=_zip_memmem(match, _zip_buffer_left(buffer)-(EOCDLEN-4), (const unsigned char *)EOCD_MAGIC, 4)) != NULL) {
+ _zip_buffer_set_offset(buffer, (zip_uint64_t)(match - _zip_buffer_data(buffer)));
+ if ((cdirnew = _zip_read_cdir(za, buffer, (zip_uint64_t)buf_offset, &error)) != NULL) {
+ if (cdir) {
+ if (best <= 0) {
+ best = _zip_checkcons(za, cdir, &error);
+ }
+
+ a = _zip_checkcons(za, cdirnew, &error);
+ if (best < a) {
+ _zip_cdir_free(cdir);
+ cdir = cdirnew;
+ best = a;
+ }
+ else {
+ _zip_cdir_free(cdirnew);
+ }
+ }
+ else {
+ cdir = cdirnew;
+ if (za->open_flags & ZIP_CHECKCONS)
+ best = _zip_checkcons(za, cdir, &error);
+ else {
+ best = 0;
+ }
+ }
+ cdirnew = NULL;
+ }
+
+ match++;
+ _zip_buffer_set_offset(buffer, (zip_uint64_t)(match - _zip_buffer_data(buffer)));
+ }
+
+ _zip_buffer_free(buffer);
+
+ if (best < 0) {
+ _zip_error_copy(&za->error, &error);
+ _zip_cdir_free(cdir);
+ return NULL;
+ }
+
+ return cdir;
+}
+
+
+static unsigned char *
+_zip_memmem(const unsigned char *big, size_t biglen, const unsigned char *little, size_t littlelen)
+{
+ const unsigned char *p;
+
+ if ((biglen < littlelen) || (littlelen == 0))
+ return NULL;
+ p = big-1;
+ while ((p=(const unsigned char *)
+ memchr(p+1, little[0], (size_t)(big-(p+1))+(size_t)(biglen-littlelen)+1)) != NULL) {
+ if (memcmp(p+1, little+1, littlelen-1)==0)
+ return (unsigned char *)p;
+ }
+
+ return NULL;
+}
+
+
+static zip_cdir_t *
+_zip_read_eocd(zip_buffer_t *buffer, zip_uint64_t buf_offset, unsigned int flags, zip_error_t *error)
+{
+ zip_cdir_t *cd;
+ zip_uint64_t i, nentry, size, offset, eocd_offset;
+
+ if (_zip_buffer_left(buffer) < EOCDLEN) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ return NULL;
+ }
+
+ eocd_offset = _zip_buffer_offset(buffer);
+
+ _zip_buffer_get(buffer, 4); /* magic already verified */
+
+ if (_zip_buffer_get_32(buffer) != 0) {
+ zip_error_set(error, ZIP_ER_MULTIDISK, 0);
+ return NULL;
+ }
+
+ /* number of cdir-entries on this disk */
+ i = _zip_buffer_get_16(buffer);
+ /* number of cdir-entries */
+ nentry = _zip_buffer_get_16(buffer);
+
+ if (nentry != i) {
+ zip_error_set(error, ZIP_ER_NOZIP, 0);
+ return NULL;
+ }
+
+ size = _zip_buffer_get_32(buffer);
+ offset = _zip_buffer_get_32(buffer);
+
+ if (offset+size < offset) {
+ zip_error_set(error, ZIP_ER_SEEK, EFBIG);
+ return NULL;
+ }
+
+ if (offset+size > buf_offset + eocd_offset) {
+ /* cdir spans past EOCD record */
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ return NULL;
+ }
+
+ if ((flags & ZIP_CHECKCONS) && offset+size != buf_offset + eocd_offset) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ return NULL;
+ }
+
+ if ((cd=_zip_cdir_new(nentry, error)) == NULL)
+ return NULL;
+
+ cd->size = size;
+ cd->offset = offset;
+
+ return cd;
+}
+
+
+static zip_cdir_t *
+_zip_read_eocd64(zip_source_t *src, zip_buffer_t *buffer, zip_uint64_t buf_offset, unsigned int flags, zip_error_t *error)
+{
+ zip_cdir_t *cd;
+ zip_uint64_t offset;
+ zip_uint8_t eocd[EOCD64LEN];
+ zip_uint64_t eocd_offset;
+ zip_uint64_t size, nentry, i, eocdloc_offset;
+ bool free_buffer;
+ zip_uint32_t num_disks, num_disks64, eocd_disk, eocd_disk64;
+
+ eocdloc_offset = _zip_buffer_offset(buffer);
+
+ _zip_buffer_get(buffer, 4); /* magic already verified */
+
+ num_disks = _zip_buffer_get_16(buffer);
+ eocd_disk = _zip_buffer_get_16(buffer);
+ eocd_offset = _zip_buffer_get_64(buffer);
+
+ if (eocd_offset > ZIP_INT64_MAX || eocd_offset + EOCD64LEN < eocd_offset) {
+ zip_error_set(error, ZIP_ER_SEEK, EFBIG);
+ return NULL;
+ }
+
+ if (eocd_offset + EOCD64LEN > eocdloc_offset + buf_offset) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ return NULL;
+ }
+
+ if (eocd_offset >= buf_offset && eocd_offset + EOCD64LEN <= buf_offset + _zip_buffer_size(buffer)) {
+ _zip_buffer_set_offset(buffer, eocd_offset - buf_offset);
+ free_buffer = false;
+ }
+ else {
+ if (zip_source_seek(src, (zip_int64_t)eocd_offset, SEEK_SET) < 0) {
+ _zip_error_set_from_source(error, src);
+ return NULL;
+ }
+ if ((buffer = _zip_buffer_new_from_source(src, EOCD64LEN, eocd, error)) == NULL) {
+ return NULL;
+ }
+ free_buffer = true;
+ }
+
+ if (memcmp(_zip_buffer_get(buffer, 4), EOCD64_MAGIC, 4) != 0) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ if (free_buffer) {
+ _zip_buffer_free(buffer);
+ }
+ return NULL;
+ }
+
+ size = _zip_buffer_get_64(buffer);
+
+ if ((flags & ZIP_CHECKCONS) && size + eocd_offset + 12 != buf_offset + eocdloc_offset) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ if (free_buffer) {
+ _zip_buffer_free(buffer);
+ }
+ return NULL;
+ }
+
+ _zip_buffer_get(buffer, 4); /* skip version made by/needed */
+
+ num_disks64 = _zip_buffer_get_32(buffer);
+ eocd_disk64 = _zip_buffer_get_32(buffer);
+
+ /* if eocd values are 0xffff, we have to use eocd64 values.
+ otherwise, if the values are not the same, it's inconsistent;
+ in any case, if the value is not 0, we don't support it */
+ if (num_disks == 0xffff) {
+ num_disks = num_disks64;
+ }
+ if (eocd_disk == 0xffff) {
+ eocd_disk = eocd_disk64;
+ }
+ if ((flags & ZIP_CHECKCONS) && (eocd_disk != eocd_disk64 || num_disks != num_disks64)) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ return NULL;
+ }
+ if (num_disks != 0 || eocd_disk != 0) {
+ zip_error_set(error, ZIP_ER_MULTIDISK, 0);
+ return NULL;
+ }
+
+ nentry = _zip_buffer_get_64(buffer);
+ i = _zip_buffer_get_64(buffer);
+
+ if (nentry != i) {
+ zip_error_set(error, ZIP_ER_MULTIDISK, 0);
+ if (free_buffer) {
+ _zip_buffer_free(buffer);
+ }
+ return NULL;
+ }
+
+ size = _zip_buffer_get_64(buffer);
+ offset = _zip_buffer_get_64(buffer);
+
+ if (!_zip_buffer_ok(buffer)) {
+ zip_error_set(error, ZIP_ER_INTERNAL, 0);
+ if (free_buffer) {
+ _zip_buffer_free(buffer);
+ }
+ return NULL;
+ }
+
+ if (free_buffer) {
+ _zip_buffer_free(buffer);
+ }
+
+ if (offset > ZIP_INT64_MAX || offset+size < offset) {
+ zip_error_set(error, ZIP_ER_SEEK, EFBIG);
+ return NULL;
+ }
+ if ((flags & ZIP_CHECKCONS) && offset+size != eocd_offset) {
+ zip_error_set(error, ZIP_ER_INCONS, 0);
+ return NULL;
+ }
+
+ if ((cd=_zip_cdir_new(nentry, error)) == NULL)
+ return NULL;
+
+
+ cd->size = size;
+ cd->offset = offset;
+
+ return cd;
+}