| /* |
| zip_open.c -- open zip archive by name |
| Copyright (C) 1999-2020 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 <stdio.h> |
| #include <stdlib.h> |
| #include <string.h> |
| |
| #include "zipint.h" |
| |
| typedef enum { EXISTS_ERROR = -1, EXISTS_NOT = 0, EXISTS_OK } 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_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; |
| |
| |
| if ((za = _zip_allocate_new(src, flags, error)) == NULL) { |
| return NULL; |
| } |
| |
| /* treat empty files as empty archives */ |
| if (len == 0 && zip_source_accept_empty(src)) { |
| return za; |
| } |
| |
| 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); |
| |
| _zip_hash_reserve_capacity(za->names, za->nentry, &za->error); |
| |
| 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); |
| switch (zip_error_system_type(err)) { |
| case ZIP_ET_SYS: |
| case ZIP_ET_LIBZIP: |
| errno = zip_error_code_system(err); |
| break; |
| |
| default: |
| break; |
| } |
| } |
| |
| 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, ZIP_ER_DETAIL_CDIR_OVERLAPS_EOCD); |
| _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, ZIP_ER_DETAIL_COMMENT_LENGTH_INVALID); |
| _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, ZIP_ER_DETAIL_CDIR_LENGTH_INVALID); |
| _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 (left > 0) { |
| bool grown = false; |
| zip_int64_t entry_size; |
| |
| if (i == cd->nentry) { |
| /* InfoZIP has a hack to avoid using Zip64: it stores nentries % 0x10000 */ |
| /* This hack isn't applicable if we're using Zip64, or if there is no central directory entry following. */ |
| |
| if (cd->is_zip64 || left < CDENTRYSIZE) { |
| break; |
| } |
| |
| if (!_zip_cdir_grow(cd, 0x10000, error)) { |
| _zip_cdir_free(cd); |
| _zip_buffer_free(cd_buffer); |
| return NULL; |
| } |
| grown = true; |
| } |
| |
| 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) { |
| if (grown && zip_error_code_zip(error) == ZIP_ER_NOZIP) { |
| zip_error_set(error, ZIP_ER_INCONS, MAKE_DETAIL_WITH_INDEX(i, ZIP_ER_DETAIL_CDIR_ENTRY_INVALID)); |
| } |
| _zip_cdir_free(cd); |
| _zip_buffer_free(cd_buffer); |
| return NULL; |
| } |
| i++; |
| left -= (zip_uint64_t)entry_size; |
| } |
| |
| if (i != cd->nentry || left > 0) { |
| zip_error_set(error, ZIP_ER_INCONS, ZIP_ER_DETAIL_CDIR_WRONG_ENTRIES_COUNT); |
| _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_cdir_free(cd); |
| return NULL; |
| } |
| ok = ((zip_uint64_t)offset == cd->offset + cd->size); |
| } |
| |
| if (!ok) { |
| zip_error_set(error, ZIP_ER_INCONS, ZIP_ER_DETAIL_CDIR_LENGTH_INVALID); |
| _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, MAKE_DETAIL_WITH_INDEX(ZIP_ER_DETAIL_ENTRY_HEADER_MISMATCH, i)); |
| _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 EXISTS_OK; |
| } |
| |
| |
| 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, ZIP_ER_DETAIL_EOCD_LENGTH_INVALID); |
| 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, ZIP_ER_DETAIL_CDIR_OVERLAPS_EOCD); |
| return NULL; |
| } |
| |
| if ((flags & ZIP_CHECKCONS) && offset + size != buf_offset + eocd_offset) { |
| zip_error_set(error, ZIP_ER_INCONS, ZIP_ER_DETAIL_CDIR_LENGTH_INVALID); |
| return NULL; |
| } |
| |
| if ((cd = _zip_cdir_new(nentry, error)) == NULL) |
| return NULL; |
| |
| cd->is_zip64 = false; |
| 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); |
| |
| /* valid seek value for start of EOCD */ |
| if (eocd_offset > ZIP_INT64_MAX) { |
| zip_error_set(error, ZIP_ER_SEEK, EFBIG); |
| return NULL; |
| } |
| |
| /* does EOCD fit before EOCD locator? */ |
| if (eocd_offset + EOCD64LEN > eocdloc_offset + buf_offset) { |
| zip_error_set(error, ZIP_ER_INCONS, ZIP_ER_DETAIL_EOCD64_OVERLAPS_EOCD); |
| return NULL; |
| } |
| |
| /* make sure current position of buffer is beginning of EOCD */ |
| 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, ZIP_ER_DETAIL_EOCD64_WRONG_MAGIC); |
| if (free_buffer) { |
| _zip_buffer_free(buffer); |
| } |
| return NULL; |
| } |
| |
| /* size of EOCD */ |
| size = _zip_buffer_get_64(buffer); |
| |
| /* is there a hole between EOCD and EOCD locator, or do they overlap? */ |
| if ((flags & ZIP_CHECKCONS) && size + eocd_offset + 12 != buf_offset + eocdloc_offset) { |
| zip_error_set(error, ZIP_ER_INCONS, ZIP_ER_DETAIL_EOCD64_OVERLAPS_EOCD); |
| 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, ZIP_ER_DETAIL_EOCD64_MISMATCH); |
| if (free_buffer) { |
| _zip_buffer_free(buffer); |
| } |
| return NULL; |
| } |
| if (num_disks != 0 || eocd_disk != 0) { |
| zip_error_set(error, ZIP_ER_MULTIDISK, 0); |
| if (free_buffer) { |
| _zip_buffer_free(buffer); |
| } |
| 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); |
| |
| /* did we read past the end of the 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 (offset + size > buf_offset + eocd_offset) { |
| /* cdir spans past EOCD record */ |
| zip_error_set(error, ZIP_ER_INCONS, ZIP_ER_DETAIL_CDIR_OVERLAPS_EOCD); |
| return NULL; |
| } |
| if ((flags & ZIP_CHECKCONS) && offset + size != buf_offset + eocd_offset) { |
| zip_error_set(error, ZIP_ER_INCONS, ZIP_ER_DETAIL_CDIR_OVERLAPS_EOCD); |
| return NULL; |
| } |
| |
| if (nentry > size / CDENTRYSIZE) { |
| zip_error_set(error, ZIP_ER_INCONS, ZIP_ER_DETAIL_CDIR_INVALID); |
| return NULL; |
| } |
| |
| if ((cd = _zip_cdir_new(nentry, error)) == NULL) |
| return NULL; |
| |
| cd->is_zip64 = true; |
| cd->size = size; |
| cd->offset = offset; |
| |
| return cd; |
| } |
