Coverage Report

Created: 2026-07-30 07:17

next uncovered line (L), next uncovered region (R), next uncovered branch (B)
/src/libzip/lib/zip_source_window.c
Line
Count
Source
1
/*
2
  zip_source_window.c -- return part of lower source
3
  Copyright (C) 2012-2025 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 <info@libzip.org>
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
#include "zipint.h"
35
36
#include <stdlib.h>
37
#include <string.h>
38
39
struct window {
40
    zip_uint64_t start; /* where in file we start reading */
41
    zip_uint64_t end;   /* where in file we stop reading */
42
    bool end_valid;     /* whether end is set, otherwise read until EOF */
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_uint64_t stat_invalid;
52
    zip_file_attributes_t attributes;
53
    zip_dostime_t dostime;
54
    bool dostime_valid;
55
    zip_error_t error;
56
    zip_int64_t supports;
57
    bool needs_seek;
58
};
59
60
static zip_int64_t window_read(zip_source_t *, void *, void *, zip_uint64_t, zip_source_cmd_t);
61
62
63
0
ZIP_EXTERN zip_source_t *zip_source_window_create(zip_source_t *src, zip_uint64_t start, zip_int64_t len, zip_error_t *error) {
64
0
    return _zip_source_window_new(src, start, len, NULL, 0, NULL, NULL, NULL, 0, false, error);
65
0
}
66
67
68
1.94k
zip_source_t *_zip_source_window_new(zip_source_t *src, zip_uint64_t start, zip_int64_t length, zip_stat_t *st, zip_uint64_t st_invalid, zip_file_attributes_t *attributes, zip_dostime_t *dostime, zip_t *source_archive, zip_uint64_t source_index, bool take_ownership, zip_error_t *error) {
69
1.94k
    zip_source_t *window_source;
70
1.94k
    struct window *ctx;
71
72
1.94k
    if (src == NULL || length < -1 || (source_archive == NULL && source_index != 0)) {
73
0
        zip_error_set(error, ZIP_ER_INVAL, 0);
74
0
        return NULL;
75
0
    }
76
77
1.94k
    if (length >= 0) {
78
1.94k
        if (start + (zip_uint64_t)length < start) {
79
0
            zip_error_set(error, ZIP_ER_INVAL, 0);
80
0
            return NULL;
81
0
        }
82
1.94k
    }
83
84
1.94k
    if ((ctx = (struct window *)malloc(sizeof(*ctx))) == NULL) {
85
0
        zip_error_set(error, ZIP_ER_MEMORY, 0);
86
0
        return NULL;
87
0
    }
88
89
1.94k
    ctx->start = start;
90
1.94k
    if (length == -1) {
91
0
        ctx->end_valid = false;
92
0
    }
93
1.94k
    else {
94
1.94k
        ctx->end = start + (zip_uint64_t)length;
95
1.94k
        ctx->end_valid = true;
96
1.94k
    }
97
1.94k
    zip_stat_init(&ctx->stat);
98
1.94k
    ctx->stat_invalid = st_invalid;
99
1.94k
    if (attributes != NULL) {
100
1.94k
        (void)memcpy_s(&ctx->attributes, sizeof(ctx->attributes), attributes, sizeof(ctx->attributes));
101
1.94k
    }
102
0
    else {
103
0
        zip_file_attributes_init(&ctx->attributes);
104
0
    }
105
1.94k
    if (dostime != NULL) {
106
1.94k
        ctx->dostime = *dostime;
107
1.94k
        ctx->dostime_valid = true;
108
1.94k
    }
109
0
    else {
110
0
        ctx->dostime_valid = false;
111
0
    }
112
1.94k
    ctx->source_archive = source_archive;
113
1.94k
    ctx->source_index = source_index;
114
1.94k
    zip_error_init(&ctx->error);
115
1.94k
    ctx->supports = (zip_source_supports(src) & (ZIP_SOURCE_SUPPORTS_SEEKABLE | ZIP_SOURCE_SUPPORTS_REOPEN)) | (zip_source_make_command_bitmap(ZIP_SOURCE_GET_FILE_ATTRIBUTES, ZIP_SOURCE_GET_DOS_TIME, ZIP_SOURCE_SUPPORTS, ZIP_SOURCE_TELL, ZIP_SOURCE_FREE, -1));
116
1.94k
    if (ctx->end_valid) {
117
1.94k
        ctx->supports |= ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_AT_EOF);
118
1.94k
    }
119
1.94k
    ctx->needs_seek = (ctx->supports & ZIP_SOURCE_MAKE_COMMAND_BITMASK(ZIP_SOURCE_SEEK)) ? true : false;
120
121
1.94k
    if (st) {
122
1.94k
        if (_zip_stat_merge(&ctx->stat, st, error) < 0) {
123
0
            free(ctx);
124
0
            return NULL;
125
0
        }
126
1.94k
    }
127
128
1.94k
    window_source = zip_source_layered_create(src, window_read, ctx, error);
129
1.94k
    if (window_source == NULL) {
130
0
        free(ctx);
131
0
        return NULL;
132
0
    }
133
1.94k
    if (!take_ownership) {
134
1.93k
        zip_source_keep(src);
135
1.93k
    }
136
1.94k
    return window_source;
137
1.94k
}
138
139
140
1.94k
int _zip_source_set_source_archive(zip_source_t *src, zip_t *za) {
141
1.94k
    src->source_archive = za;
142
1.94k
    return _zip_register_source(za, src);
143
1.94k
}
144
145
146
/* called by zip_discard to avoid operating on file from closed archive */
147
0
void _zip_source_invalidate(zip_source_t *src) {
148
0
    src->source_closed = 1;
149
150
0
    if (zip_error_code_zip(&src->error) == ZIP_ER_OK) {
151
0
        zip_error_set(&src->error, ZIP_ER_ZIPCLOSED, 0);
152
0
    }
153
0
}
154
155
156
17.6k
static zip_int64_t window_read(zip_source_t *src, void *_ctx, void *data, zip_uint64_t len, zip_source_cmd_t cmd) {
157
17.6k
    struct window *ctx;
158
17.6k
    zip_int64_t ret;
159
17.6k
    zip_uint64_t n, i;
160
161
17.6k
    ctx = (struct window *)_ctx;
162
163
17.6k
    switch (cmd) {
164
798
    case ZIP_SOURCE_AT_EOF:
165
798
        if (ctx->end_valid) {
166
798
            return ctx->offset == ctx->end;
167
798
        }
168
0
        else {
169
0
            return zip_source_pass_to_lower_layer(src, data, len, cmd);
170
0
        }
171
172
1.92k
    case ZIP_SOURCE_CLOSE:
173
1.92k
        return 0;
174
175
1.93k
    case ZIP_SOURCE_ERROR:
176
1.93k
        return zip_error_to_data(&ctx->error, data, len);
177
178
1.94k
    case ZIP_SOURCE_FREE:
179
1.94k
        free(ctx);
180
1.94k
        return 0;
181
182
1.93k
    case ZIP_SOURCE_OPEN:
183
1.93k
        if (ctx->source_archive) {
184
1.92k
            zip_uint64_t offset;
185
186
1.92k
            if ((offset = _zip_file_get_offset(ctx->source_archive, ctx->source_index, &ctx->error)) == 0) {
187
11
                return -1;
188
11
            }
189
1.91k
            if (ctx->end_valid) {
190
1.91k
                if (ctx->end + offset < ctx->end) {
191
                    /* zip archive data claims end of data past zip64 limits */
192
0
                    zip_error_set(&ctx->error, ZIP_ER_INCONS, MAKE_DETAIL_WITH_INDEX(ZIP_ER_DETAIL_CDIR_ENTRY_INVALID, ctx->source_index));
193
0
                    return -1;
194
0
                }
195
1.91k
                ctx->end += offset;
196
1.91k
            }
197
1.91k
            ctx->start += offset;
198
1.91k
            ctx->source_archive = NULL;
199
1.91k
        }
200
201
1.92k
        if (!ctx->needs_seek) {
202
0
            DEFINE_BYTE_ARRAY(b, BUFSIZE);
203
204
0
            if (!byte_array_init(b, BUFSIZE)) {
205
0
                zip_error_set(&ctx->error, ZIP_ER_MEMORY, 0);
206
0
                return -1;
207
0
            }
208
209
0
            for (n = 0; n < ctx->start; n += (zip_uint64_t)ret) {
210
0
                i = (ctx->start - n > BUFSIZE ? BUFSIZE : ctx->start - n);
211
0
                if ((ret = zip_source_read(src, b, i)) < 0) {
212
0
                    zip_error_set_from_source(&ctx->error, src);
213
0
                    byte_array_fini(b);
214
0
                    return -1;
215
0
                }
216
0
                if (ret == 0) {
217
0
                    zip_error_set(&ctx->error, ZIP_ER_EOF, 0);
218
0
                    byte_array_fini(b);
219
0
                    return -1;
220
0
                }
221
0
            }
222
223
0
            byte_array_fini(b);
224
0
        }
225
226
1.92k
        ctx->offset = ctx->start;
227
1.92k
        return 0;
228
229
3.03k
    case ZIP_SOURCE_READ:
230
3.03k
        if (ctx->end_valid && len > ctx->end - ctx->offset) {
231
2.19k
            len = ctx->end - ctx->offset;
232
2.19k
        }
233
234
3.03k
        if (len == 0) {
235
1.08k
            return 0;
236
1.08k
        }
237
238
1.94k
        if (ctx->needs_seek) {
239
1.94k
            if (zip_source_seek(src, (zip_int64_t)ctx->offset, SEEK_SET) < 0) {
240
48
                zip_error_set_from_source(&ctx->error, src);
241
48
                return -1;
242
48
            }
243
1.94k
        }
244
245
1.89k
        if ((ret = zip_source_read(src, data, len)) < 0) {
246
0
            zip_error_set_from_source(&ctx->error, src);
247
0
            return -1;
248
0
        }
249
250
1.89k
        if (ret == 0) {
251
26
            if (ctx->end_valid && ctx->offset < ctx->end) {
252
26
                zip_error_set(&ctx->error, ZIP_ER_EOF, 0);
253
26
                return -1;
254
26
            }
255
26
        }
256
257
1.87k
        ctx->offset += (zip_uint64_t)ret;
258
1.87k
        return ret;
259
260
0
    case ZIP_SOURCE_SEEK: {
261
0
        zip_int64_t new_offset;
262
263
0
        if (!ctx->end_valid) {
264
0
            zip_source_args_seek_t *args = ZIP_SOURCE_GET_ARGS(zip_source_args_seek_t, data, len, &ctx->error);
265
266
0
            if (args == NULL) {
267
0
                return -1;
268
0
            }
269
0
            if (args->whence == SEEK_END) {
270
0
                if (zip_source_seek(src, args->offset, args->whence) < 0) {
271
0
                    zip_error_set_from_source(&ctx->error, src);
272
0
                    return -1;
273
0
                }
274
0
                new_offset = zip_source_tell(src);
275
0
                if (new_offset < 0) {
276
0
                    zip_error_set_from_source(&ctx->error, src);
277
0
                    return -1;
278
0
                }
279
0
                if ((zip_uint64_t)new_offset < ctx->start) {
280
0
                    zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
281
0
                    (void)zip_source_seek(src, (zip_int64_t)ctx->offset, SEEK_SET);
282
0
                    return -1;
283
0
                }
284
0
                ctx->offset = (zip_uint64_t)new_offset;
285
0
                return 0;
286
0
            }
287
0
            else {
288
0
                if (args->whence == SEEK_CUR) {
289
0
                    if (args->offset > 0 && (zip_int64_t)ctx->offset + args->offset < args->offset) {
290
0
                        zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
291
0
                        return -1;
292
0
                    }
293
0
                    args->offset += (zip_int64_t)ctx->offset;
294
0
                }
295
0
                if (args->offset < 0) {
296
0
                    zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
297
0
                    return -1;
298
0
                }
299
0
                if (zip_source_seek(src, args->offset, SEEK_SET) < 0) {
300
0
                    zip_error_set_from_source(&ctx->error, src);
301
0
                    return -1;
302
0
                }
303
0
                ctx->offset = (zip_uint64_t)args->offset;
304
0
                return 0;
305
0
            }
306
0
        }
307
0
        else {
308
0
            new_offset = zip_source_seek_compute_offset(ctx->offset - ctx->start, ctx->end - ctx->start, data, len, &ctx->error);
309
310
0
            if (new_offset < 0) {
311
0
                return -1;
312
0
            }
313
314
0
            ctx->offset = (zip_uint64_t)new_offset + ctx->start;
315
0
            return 0;
316
0
        }
317
0
    }
318
319
3.04k
    case ZIP_SOURCE_STAT: {
320
3.04k
        zip_stat_t *st;
321
322
3.04k
        st = (zip_stat_t *)data;
323
324
3.04k
        if (_zip_stat_merge(st, &ctx->stat, &ctx->error) < 0) {
325
0
            return -1;
326
0
        }
327
328
3.04k
        if (!(ctx->stat.valid & ZIP_STAT_SIZE)) {
329
0
            if (ctx->end_valid) {
330
0
                st->valid |= ZIP_STAT_SIZE;
331
0
                st->size = ctx->end - ctx->start;
332
0
            }
333
0
            else if (st->valid & ZIP_STAT_SIZE) {
334
0
                st->size -= ctx->start;
335
0
            }
336
0
        }
337
338
3.04k
        st->valid &= ~ctx->stat_invalid;
339
340
3.04k
        return 0;
341
3.04k
    }
342
343
1.11k
    case ZIP_SOURCE_GET_FILE_ATTRIBUTES:
344
1.11k
        if (len < sizeof(ctx->attributes)) {
345
0
            zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
346
0
            return -1;
347
0
        }
348
349
1.11k
        (void)memcpy_s(data, sizeof(ctx->attributes), &ctx->attributes, sizeof(ctx->attributes));
350
1.11k
        return sizeof(ctx->attributes);
351
352
0
    case ZIP_SOURCE_GET_DOS_TIME:
353
0
        if (len < sizeof(ctx->dostime)) {
354
0
            zip_error_set(&ctx->error, ZIP_ER_INVAL, 0);
355
0
            return -1;
356
0
        }
357
0
        if (ctx->dostime_valid) {
358
0
            (void)memcpy_s(data, sizeof(ctx->dostime), &ctx->dostime, sizeof(ctx->dostime));
359
0
            return sizeof(ctx->dostime);
360
0
        }
361
0
        else {
362
0
            return 0;
363
0
        }
364
365
1.94k
    case ZIP_SOURCE_SUPPORTS:
366
1.94k
        return ctx->supports;
367
368
0
    case ZIP_SOURCE_TELL:
369
0
        return (zip_int64_t)(ctx->offset - ctx->start);
370
371
0
    default:
372
0
        return zip_source_pass_to_lower_layer(src, data, len, cmd);
373
17.6k
    }
374
17.6k
}
375
376
377
1.94k
void _zip_deregister_source(zip_t *za, zip_source_t *src) {
378
1.94k
    zip_uint64_t i;
379
380
1.94k
    for (i = 0; i < za->nopen_source; i++) {
381
1.94k
        if (za->open_source[i] == src) {
382
1.94k
            za->open_source[i] = za->open_source[za->nopen_source - 1];
383
1.94k
            za->nopen_source--;
384
1.94k
            break;
385
1.94k
        }
386
1.94k
    }
387
1.94k
}
388
389
390
1.94k
int _zip_register_source(zip_t *za, zip_source_t *src) {
391
1.94k
    if (za->nopen_source + 1 >= za->nopen_source_alloc) {
392
829
        if (!ZIP_REALLOC(za->open_source, za->nopen_source_alloc, 10, &za->error)) {
393
0
            return -1;
394
0
        }
395
829
    }
396
397
1.94k
    za->open_source[za->nopen_source++] = src;
398
399
1.94k
    return 0;
400
1.94k
}