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Member "src/Common/libzip/zip_source_window.c" (10 Oct 2018, 7488 Bytes) of package /windows/misc/VeraCrypt_1.23-Hotfix-2_Source.zip:


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    1 /*
    2   zip_source_window.c -- return part of lower source
    3   Copyright (C) 2012-2017 Dieter Baron and Thomas Klausner
    4 
    5   This file is part of libzip, a library to manipulate ZIP archives.
    6   The authors can be contacted at <libzip@nih.at>
    7 
    8   Redistribution and use in source and binary forms, with or without
    9   modification, are permitted provided that the following conditions
   10   are met:
   11   1. Redistributions of source code must retain the above copyright
   12      notice, this list of conditions and the following disclaimer.
   13   2. Redistributions in binary form must reproduce the above copyright
   14      notice, this list of conditions and the following disclaimer in
   15      the documentation and/or other materials provided with the
   16      distribution.
   17   3. The names of the authors may not be used to endorse or promote
   18      products derived from this software without specific prior
   19      written permission.
   20 
   21   THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
   22   OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
   23   WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   24   ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
   25   DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   26   DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
   27   GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
   28   INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
   29   IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
   30   OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
   31   IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   32 */
   33 
   34 
   35 #include <stdlib.h>
   36 #include <string.h>
   37 
   38 #include "zipint.h"
   39 
   40 struct window {
   41     zip_uint64_t start; /* where in file we start reading */
   42     zip_uint64_t end;   /* where in file we stop reading */
   43 
   44     /* if not NULL, read file data for this file */
   45     zip_t *source_archive;
   46     zip_uint64_t source_index;
   47 
   48     zip_uint64_t offset; /* offset in src for next read */
   49 
   50     zip_stat_t stat;
   51     zip_int8_t compression_flags;
   52     zip_error_t error;
   53     zip_int64_t supports;
   54     bool needs_seek;
   55 };
   56 
   57 static zip_int64_t window_read(zip_source_t *, void *, void *, zip_uint64_t, zip_source_cmd_t);
   58 
   59 
   60 zip_source_t *
   61 zip_source_window(zip_t *za, zip_source_t *src, zip_uint64_t start, zip_uint64_t len) {
   62     return _zip_source_window_new(src, start, len, NULL, 0, NULL, 0, &za->error);
   63 }
   64 
   65 
   66 zip_source_t *
   67 _zip_source_window_new(zip_source_t *src, zip_uint64_t start, zip_uint64_t length, zip_stat_t *st, zip_int8_t compression_flags, zip_t *source_archive, zip_uint64_t source_index, zip_error_t *error) {
   68     struct window *ctx;
   69 
   70     if (src == NULL || start + length < start || (source_archive == NULL && source_index != 0)) {
   71     zip_error_set(error, ZIP_ER_INVAL, 0);
   72     return NULL;
   73     }
   74 
   75     if ((ctx = (struct window *)malloc(sizeof(*ctx))) == NULL) {
   76     zip_error_set(error, ZIP_ER_MEMORY, 0);
   77     return NULL;
   78     }
   79 
   80     ctx->start = start;
   81     ctx->end = start + length;
   82     zip_stat_init(&ctx->stat);
   83     ctx->compression_flags = compression_flags;
   84     ctx->source_archive = source_archive;
   85     ctx->source_index = source_index;
   86     zip_error_init(&ctx->error);
   87     ctx->supports = (zip_source_supports(src) & ZIP_SOURCE_SUPPORTS_SEEKABLE) | (zip_source_make_command_bitmap(ZIP_SOURCE_GET_COMPRESSION_FLAGS, ZIP_SOURCE_SUPPORTS, ZIP_SOURCE_TELL, -1));
   88     ctx->needs_seek = (ctx->supports & ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_SEEK)) ? true : false;
   89 
   90     if (st) {
   91     if (_zip_stat_merge(&ctx->stat, st, error) < 0) {
   92         free(ctx);
   93         return NULL;
   94     }
   95     }
   96 
   97     return zip_source_layered_create(src, window_read, ctx, error);
   98 }
   99 
  100 
  101 int
  102 _zip_source_set_source_archive(zip_source_t *src, zip_t *za) {
  103     src->source_archive = za;
  104     return _zip_register_source(za, src);
  105 }
  106 
  107 
  108 /* called by zip_discard to avoid operating on file from closed archive */
  109 void
  110 _zip_source_invalidate(zip_source_t *src) {
  111     src->source_closed = 1;
  112 
  113     if (zip_error_code_zip(&src->error) == ZIP_ER_OK) {
  114     zip_error_set(&src->error, ZIP_ER_ZIPCLOSED, 0);
  115     }
  116 }
  117 
  118 
  119 static zip_int64_t
  120 window_read(zip_source_t *src, void *_ctx, void *data, zip_uint64_t len, zip_source_cmd_t cmd) {
  121     struct window *ctx;
  122     zip_int64_t ret;
  123     zip_uint64_t n, i;
  124     char b[8192];
  125 
  126     ctx = (struct window *)_ctx;
  127 
  128     switch (cmd) {
  129     case ZIP_SOURCE_CLOSE:
  130     return 0;
  131 
  132     case ZIP_SOURCE_ERROR:
  133     return zip_error_to_data(&ctx->error, data, len);
  134 
  135     case ZIP_SOURCE_FREE:
  136     free(ctx);
  137     return 0;
  138 
  139     case ZIP_SOURCE_OPEN:
  140     if (ctx->source_archive) {
  141         zip_uint64_t offset;
  142 
  143         if ((offset = _zip_file_get_offset(ctx->source_archive, ctx->source_index, &ctx->error)) == 0) {
  144         return -1;
  145         }
  146         if (ctx->end + offset < ctx->end) {
  147         /* zip archive data claims end of data past zip64 limits */
  148         zip_error_set(&ctx->error, ZIP_ER_INCONS, 0);
  149         return -1;
  150         }
  151         ctx->start += offset;
  152         ctx->end += offset;
  153         ctx->source_archive = NULL;
  154     }
  155 
  156     if (!ctx->needs_seek) {
  157         for (n = 0; n < ctx->start; n += (zip_uint64_t)ret) {
  158         i = (ctx->start - n > sizeof(b) ? sizeof(b) : ctx->start - n);
  159         if ((ret = zip_source_read(src, b, i)) < 0) {
  160             _zip_error_set_from_source(&ctx->error, src);
  161             return -1;
  162         }
  163         if (ret == 0) {
  164             zip_error_set(&ctx->error, ZIP_ER_EOF, 0);
  165             return -1;
  166         }
  167         }
  168     }
  169     ctx->offset = ctx->start;
  170     return 0;
  171 
  172     case ZIP_SOURCE_READ:
  173     if (len > ctx->end - ctx->offset)
  174         len = ctx->end - ctx->offset;
  175 
  176     if (len == 0)
  177         return 0;
  178 
  179     if (ctx->needs_seek) {
  180         if (zip_source_seek(src, (zip_int64_t)ctx->offset, SEEK_SET) < 0) {
  181         _zip_error_set_from_source(&ctx->error, src);
  182         return -1;
  183         }
  184     }
  185 
  186     if ((ret = zip_source_read(src, data, len)) < 0) {
  187         zip_error_set(&ctx->error, ZIP_ER_EOF, 0);
  188         return -1;
  189     }
  190 
  191     ctx->offset += (zip_uint64_t)ret;
  192 
  193     if (ret == 0) {
  194         if (ctx->offset < ctx->end) {
  195         zip_error_set(&ctx->error, ZIP_ER_EOF, 0);
  196         return -1;
  197         }
  198     }
  199     return ret;
  200 
  201     case ZIP_SOURCE_SEEK: {
  202     zip_int64_t new_offset = zip_source_seek_compute_offset(ctx->offset - ctx->start, ctx->end - ctx->start, data, len, &ctx->error);
  203 
  204     if (new_offset < 0) {
  205         return -1;
  206     }
  207 
  208     ctx->offset = (zip_uint64_t)new_offset + ctx->start;
  209     return 0;
  210     }
  211 
  212     case ZIP_SOURCE_STAT: {
  213     zip_stat_t *st;
  214 
  215     st = (zip_stat_t *)data;
  216 
  217     if (_zip_stat_merge(st, &ctx->stat, &ctx->error) < 0) {
  218         return -1;
  219     }
  220     return 0;
  221     }
  222 
  223     case ZIP_SOURCE_GET_COMPRESSION_FLAGS:
  224     return ctx->compression_flags;
  225 
  226     case ZIP_SOURCE_SUPPORTS:
  227     return ctx->supports;
  228 
  229     case ZIP_SOURCE_TELL:
  230     return (zip_int64_t)(ctx->offset - ctx->start);
  231 
  232     default:
  233     zip_error_set(&ctx->error, ZIP_ER_OPNOTSUPP, 0);
  234     return -1;
  235     }
  236 }
  237 
  238 
  239 void
  240 _zip_deregister_source(zip_t *za, zip_source_t *src) {
  241     unsigned int i;
  242 
  243     for (i = 0; i < za->nopen_source; i++) {
  244     if (za->open_source[i] == src) {
  245         za->open_source[i] = za->open_source[za->nopen_source - 1];
  246         za->nopen_source--;
  247         break;
  248     }
  249     }
  250 }
  251 
  252 
  253 int
  254 _zip_register_source(zip_t *za, zip_source_t *src) {
  255     zip_source_t **open_source;
  256 
  257     if (za->nopen_source + 1 >= za->nopen_source_alloc) {
  258     unsigned int n;
  259     n = za->nopen_source_alloc + 10;
  260     open_source = (zip_source_t **)realloc(za->open_source, n * sizeof(zip_source_t *));
  261     if (open_source == NULL) {
  262         zip_error_set(&za->error, ZIP_ER_MEMORY, 0);
  263         return -1;
  264     }
  265     za->nopen_source_alloc = n;
  266     za->open_source = open_source;
  267     }
  268 
  269     za->open_source[za->nopen_source++] = src;
  270 
  271     return 0;
  272 }