summaryrefslogtreecommitdiffstats
path: root/src/tools/files.c
blob: d80e3bd9a387f69cb7bf11dc2b09fe07a928911a (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
/*
    Authors:
        Jakub Hrozek <jhrozek@redhat.com>

    Copyright (C) 2009 Red Hat

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 3 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

/*
 * This file incorporates work covered by the following copyright and
 * permission notice:
 *
 * Copyright (c) 1991 - 1994, Julianne Frances Haugh
 * Copyright (c) 1996 - 2001, Marek Michałkiewicz
 * Copyright (c) 2003 - 2006, Tomasz Kłoczko
 * Copyright (c) 2007 - 2008, Nicolas François
 *
 * All rights reserved.
 *
 * 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 name of the copyright holders or contributors may not be used to
 *    endorse or promote products derived from this software without
 *    specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``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 COPYRIGHT
 * HOLDERS OR CONTRIBUTORS 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 <sys/types.h>
#include <sys/time.h>
#include <dirent.h>
#include <fcntl.h>
#include <errno.h>
#include <talloc.h>

#include "config.h"
#include "util/util.h"
#include "tools/tools_util.h"

int copy_tree(const char *src_root, const char *dst_root,
              uid_t uid, gid_t gid);

struct copy_ctx {
    const char *src_orig;
    const char *dst_orig;
    dev_t       src_dev;
};

/* wrapper in order not to create a temporary context in
 * every iteration */
static int remove_tree_with_ctx(TALLOC_CTX *mem_ctx,
                                dev_t parent_dev,
                                const char *root);

int remove_tree(const char *root)
{
    TALLOC_CTX *tmp_ctx = NULL;
    int ret;

    tmp_ctx = talloc_new(NULL);
    if (!tmp_ctx) {
        return ENOMEM;
    }

    ret = remove_tree_with_ctx(tmp_ctx, 0, root);
    talloc_free(tmp_ctx);
    return ret;
}

/*
 * The context is not freed in case of error
 * because this is a recursive function, will be freed when we
 * reach the top level remove_tree() again
 */
static int remove_tree_with_ctx(TALLOC_CTX *mem_ctx,
                                dev_t parent_dev,
                                const char *root)
{
    char *fullpath = NULL;
    struct dirent *result;
    struct dirent direntp;
    struct stat statres;
    DIR *rootdir = NULL;
    int ret, err;

    rootdir = opendir(root);
    if (rootdir == NULL) {
        ret = errno;
        DEBUG(1, ("Cannot open directory %s [%d][%s]\n",
                  root, ret, strerror(ret)));
        goto fail;
    }

    while (readdir_r(rootdir, &direntp, &result) == 0) {
        if (result == NULL) {
            /* End of directory */
            break;
        }

        if (strcmp (direntp.d_name, ".") == 0 ||
            strcmp (direntp.d_name, "..") == 0) {
            continue;
        }

        fullpath = talloc_asprintf(mem_ctx, "%s/%s", root, direntp.d_name);
        if (fullpath == NULL) {
            ret = ENOMEM;
            goto fail;
        }

        ret = lstat(fullpath, &statres);
        if (ret != 0) {
            ret = errno;
            DEBUG(1, ("Cannot stat %s: [%d][%s]\n",
                      fullpath, ret, strerror(ret)));
            goto fail;
        }

        if (S_ISDIR(statres.st_mode)) {
            /* if directory, recursively descend, but check if on the same FS */
            if (parent_dev && parent_dev != statres.st_dev) {
                DEBUG(1, ("Directory %s is on different filesystem, "
                          "will not follow\n", fullpath));
                ret = EFAULT;
                goto fail;
            }

            ret = remove_tree_with_ctx(mem_ctx, statres.st_dev, fullpath);
            if (ret != EOK) {
                DEBUG(1, ("Removing subdirectory %s failed: [%d][%s]\n",
                            fullpath, ret, strerror(ret)));
                goto fail;
            }
        } else {
            ret = unlink(fullpath);
            if (ret != 0) {
                ret = errno;
                DEBUG(1, ("Removing file %s failed: [%d][%s]\n",
                          fullpath, ret, strerror(ret)));
                goto fail;
            }
        }

        talloc_free(fullpath);
    }

    ret = closedir(rootdir);
    rootdir = NULL;
    if (ret != 0) {
        ret = errno;
        goto fail;
    }

    ret = rmdir(root);
    if (ret != 0) {
        ret = errno;
        goto fail;
    }

    ret = EOK;

fail:
    if (rootdir) {  /* clean up on abnormal exit but retain return code */
        err = closedir(rootdir);
        if (err) {
            DEBUG(1, ("closedir failed, bad dirp?\n"));
        }
    }
    return ret;
}

static int copy_dir(const char *src, const char *dst,
                    const struct stat *statp, const struct timeval mt[2],
                    uid_t uid, gid_t gid)
{
    int ret = 0;

    /*
     * Create a new target directory, make it owned by
     * the user and then recursively copy that directory.
     */
    selinux_file_context(dst);

    ret = mkdir(dst, statp->st_mode);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot mkdir directory '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        return ret;
    }

    ret = chown(dst, uid, gid);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot chown directory '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        return ret;
    }

    ret = chmod(dst, statp->st_mode);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot chmod directory '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        return ret;
    }

    ret = copy_tree(src, dst, uid, gid);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot copy directory from '%s' to '%s': [%d][%s].\n",
                  src, dst, ret, strerror(ret)));
        return ret;
    }

    ret = utimes(dst, mt);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot set utimes on a directory '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        return ret;
    }

    return EOK;
}

static char *talloc_readlink(TALLOC_CTX *mem_ctx, const char *filename)
{
    size_t size = 1024;
    ssize_t nchars;
    char *buffer;

    buffer = talloc_array(mem_ctx, char, size);
    if (!buffer) {
        return NULL;
    }

    while (1) {
        nchars = readlink(filename, buffer, size);
        if (nchars < 0) {
            return NULL;
        }

        if ((size_t) nchars < size) {
            /* The buffer was large enough */
            break;
        }

        /* Try again with a bigger buffer */
        size *= 2;
        buffer = talloc_realloc(mem_ctx, buffer, char, size);
        if (!buffer) {
            return NULL;
        }
    }

    /* readlink does not nul-terminate */
    buffer[nchars] = '\0';
    return buffer;
}

static int copy_symlink(struct copy_ctx *cctx,
                        const char *src,
                        const char *dst,
                        const struct stat *statp,
                        const struct timeval mt[],
                        uid_t uid, gid_t gid)
{
    int ret;
    char *oldlink;
    char *tmp;
    TALLOC_CTX *tmp_ctx = NULL;

    tmp_ctx = talloc_new(cctx);
    if (!tmp_ctx) {
        return ENOMEM;
    }

    /*
     * Get the name of the file which the link points
     * to.  If that name begins with the original
     * source directory name, that part of the link
     * name will be replaced with the original
     * destination directory name.
     */
    oldlink = talloc_readlink(tmp_ctx, src);
    if (oldlink == NULL) {
        ret = ENOMEM;
        goto done;
    }

    /* If src was a link to an entry of the src_orig directory itself,
     * create a link to the corresponding entry in the dst_orig
     * directory.
     * FIXME: This may change a relative link to an absolute link
     */
    if (strncmp(oldlink, cctx->src_orig, strlen(cctx->src_orig)) == 0) {
        tmp = talloc_asprintf(tmp_ctx, "%s%s", cctx->dst_orig, oldlink + strlen(cctx->src_orig));
        if (tmp == NULL) {
            ret = ENOMEM;
            goto done;
        }

        talloc_free(oldlink);
        oldlink = tmp;
    }

    selinux_file_context(dst);

    ret = symlink(oldlink, dst);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("symlink() failed on file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        goto done;
    }

    ret = lchown(dst, uid, gid);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("lchown() failed on file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        goto done;
    }

done:
    talloc_free(tmp_ctx);
    return ret;
}

static int copy_special(const char *dst,
                        const struct stat *statp,
                        const struct timeval mt[],
                        uid_t uid, gid_t gid)
{
    int ret = 0;

    selinux_file_context(dst);

    ret = mknod(dst, statp->st_mode & ~07777, statp->st_rdev);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot mknod special file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        return ret;
    }

    ret = chown(dst, uid, gid);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot chown special file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        return ret;
    }

    ret = chmod(dst, statp->st_mode & 07777);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot chmod special file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        return ret;
    }

    ret = utimes(dst, mt);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot call utimes on special file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        return ret;
    }

    return EOK;
}

static int copy_file(const char *src,
                     const char *dst,
                     const struct stat *statp,
                     const struct timeval mt[],
                     uid_t uid, gid_t gid)
{
    int ret;
    int ifd = -1;
    int ofd = -1;
    char buf[1024];
    ssize_t cnt, written;
    struct stat fstatbuf;

    ifd = open(src, O_RDONLY);
    if (ifd < 0) {
        ret = errno;
        DEBUG(1, ("Cannot open() source file '%s': [%d][%s].\n",
                  src, ret, strerror(ret)));
        goto fail;
    }

    ret = fstat(ifd, &fstatbuf);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot fstat() source file '%s': [%d][%s].\n",
                  src, ret, strerror(ret)));
        goto fail;
    }

    if (statp->st_dev != fstatbuf.st_dev ||
        statp->st_ino != fstatbuf.st_ino) {
        DEBUG(1, ("File %s was modified between lstat and open.\n", src));
        ret = EIO;
        goto fail;
    }

    selinux_file_context(dst);

    ofd = open(dst, O_WRONLY | O_CREAT | O_TRUNC, statp->st_mode & 07777);
    if (ofd < 0) {
        ret = errno;
        DEBUG(1, ("Cannot open() destination file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        goto fail;
    }

    ret = fchown(ofd, uid, gid);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot fchown() destination file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        goto fail;
    }

    ret = fchmod(ofd, statp->st_mode & 07777);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot fchmod() destination file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        goto fail;
    }

    while ((cnt = sss_atomic_read_s(ifd, buf, sizeof(buf))) != 0) {
        if (cnt == -1) {
            ret = errno;
            DEBUG(SSSDBG_CRIT_FAILURE,
                  ("Cannot read() from source file '%s': [%d][%s].\n",
                   src, ret, strerror(ret)));
            goto fail;
        }

        errno = 0;
        written = sss_atomic_write_s(ofd, buf, cnt);
        if (written == -1) {
            ret = errno;
            DEBUG(SSSDBG_CRIT_FAILURE,
                  ("Cannot write() to destination file '%s': [%d][%s].\n",
                   dst, ret, strerror(ret)));
            goto fail;
        }

        if (written != cnt) {
            DEBUG(SSSDBG_CRIT_FAILURE,
                  ("Wrote %d bytes, expected %d\n", written, cnt));
            goto fail;
        }
    }

    ret = close(ifd);
    ifd = -1;
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot close() source file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        goto fail;
    }

    ret = close(ofd);
    ifd = -1;
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot close() destination file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        goto fail;
    }

    ret = utimes(dst, mt);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot call utimes() on destination file '%s': [%d][%s].\n",
                  dst, ret, strerror(ret)));
        goto fail;
    }

    return EOK;

    /* Reachable by jump only */
fail:
    if (ifd != -1) close(ifd);
    if (ofd != -1) close(ofd);
    return ret;
}

/*
 * The context is not freed in case of error
 * because this is a recursive function, will be freed when we
 * reach the top level copy_tree() again
 */
static int copy_entry(struct copy_ctx *cctx,
                      const char *src,
                      const char *dst,
                      uid_t uid,
                      gid_t gid)
{
    int ret = EOK;
    struct stat sb;
    struct timeval mt[2];

    ret = lstat(src, &sb);
    if (ret == -1) {
        ret = errno;
        DEBUG(1, ("Cannot lstat() the source file '%s': [%d][%s].\n",
                  src, ret, strerror(ret)));
        return ret;
    }

    mt[0].tv_sec  = sb.st_atime;
    mt[0].tv_usec = 0;

    mt[1].tv_sec  = sb.st_mtime;
    mt[1].tv_usec = 0;

    if (S_ISLNK (sb.st_mode)) {
        ret = copy_symlink(cctx, src, dst, &sb, mt, uid, gid);
        if (ret != EOK) {
            DEBUG(1, ("Cannot copy symlink '%s' to '%s': [%d][%s]\n",
                      src, dst, ret, strerror(ret)));
        }
        return ret;
    }

    if (S_ISDIR(sb.st_mode)) {
        /* Check if we're still on the same FS */
        if (sb.st_dev != cctx->src_dev) {
            DEBUG(2, ("Will not descend to other FS\n"));
            /* Skip this without error */
            return EOK;
        }
        return copy_dir(src, dst, &sb, mt, uid, gid);
    } else if (!S_ISREG(sb.st_mode)) {
        /*
         * Deal with FIFOs and special files.  The user really
         * shouldn't have any of these, but it seems like it
         * would be nice to copy everything ...
         */
        return copy_special(dst, &sb, mt, uid, gid);
    } else {
        /*
         * Create the new file and copy the contents.  The new
         * file will be owned by the provided UID and GID values.
         */
        return copy_file(src, dst, &sb, mt, uid, gid);
    }

    return ret;
}

/*
 * The context is not freed in case of error
 * because this is a recursive function, will be freed when we
 * reach the top level copy_tree() again
 */
static int copy_tree_ctx(struct copy_ctx *cctx,
                         const char *src_root,
                         const char *dst_root,
                         uid_t uid,
                         gid_t gid)
{
    DIR *src_dir = NULL;
    int ret, err;
    struct dirent *result;
    struct dirent direntp;
    char *src_name, *dst_name;
    TALLOC_CTX *tmp_ctx;

    tmp_ctx = talloc_new(cctx);

    src_dir = opendir(src_root);
    if (src_dir == NULL) {
        ret = errno;
        DEBUG(1, ("Cannot open the source directory %s: [%d][%s].\n",
                  src_root, ret, strerror(ret)));
        goto fail;
    }

    while (readdir_r(src_dir, &direntp, &result) == 0) {
        if (result == NULL) {
            /* End of directory */
            break;
        }

        if (strcmp (direntp.d_name, ".") == 0 ||
            strcmp (direntp.d_name, "..") == 0) {
            continue;
        }

        /* build src and dst paths */
        src_name = talloc_asprintf(tmp_ctx, "%s/%s", src_root, direntp.d_name);
        dst_name = talloc_asprintf(tmp_ctx, "%s/%s", dst_root, direntp.d_name);
        if (dst_name == NULL || src_name == NULL) {
            ret = ENOMEM;
            goto fail;
        }

        /* copy */
        ret = copy_entry(cctx, src_name, dst_name, uid, gid);
        if (ret != EOK) {
            DEBUG(1, ("Cannot copy '%s' to '%s', error %d\n",
                      src_name, dst_name, ret));
            goto fail;
        }
        talloc_free(src_name);
        talloc_free(dst_name);
    }

    ret = closedir(src_dir);
    src_dir = NULL;
    if (ret != 0) {
        ret = errno;
        goto fail;
    }

    ret = EOK;
fail:
    if (src_dir) {  /* clean up on abnormal exit but retain return code */
        err = closedir(src_dir);
        if (err) {
            DEBUG(1, ("closedir failed, bad dirp?\n"));
        }
    }
    talloc_free(tmp_ctx);
    return ret;
}

int copy_tree(const char *src_root, const char *dst_root,
              uid_t uid, gid_t gid)
{
    int ret = EOK;
    struct copy_ctx *cctx = NULL;
    struct stat s_src;

    cctx = talloc_zero(NULL, struct copy_ctx);

    ret = lstat(src_root, &s_src);
    if (ret != 0) {
        ret = errno;
        DEBUG(1, ("Cannot lstat the source directory '%s': [%d][%s]\n",
                  src_root, ret, strerror(ret)));
        goto fail;
    }

    cctx->src_orig = src_root;
    cctx->dst_orig = dst_root;
    cctx->src_dev  = s_src.st_dev;

    ret = copy_tree_ctx(cctx, src_root, dst_root, uid, gid);
    if (ret != EOK) {
        DEBUG(1, ("copy_tree_ctx failed: [%d][%s]\n", ret, strerror(ret)));
        goto fail;
    }

fail:
    reset_selinux_file_context();
    talloc_free(cctx);
    return ret;
}