1/*
2 * Copyright (C) 2012 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17#include <stdio.h>
18#include <stdlib.h>
19#include <string.h>
20#include <unistd.h>
21#include <fcntl.h>
22#include <ctype.h>
23#include <sys/mount.h>
24#include <sys/stat.h>
25#include <errno.h>
26#include <sys/types.h>
27#include <sys/wait.h>
28#include <libgen.h>
29#include <time.h>
30#include <sys/swap.h>
31/* XXX These need to be obtained from kernel headers. See b/9336527 */
32#define SWAP_FLAG_PREFER        0x8000
33#define SWAP_FLAG_PRIO_MASK     0x7fff
34#define SWAP_FLAG_PRIO_SHIFT    0
35#define SWAP_FLAG_DISCARD       0x10000
36
37#include <linux/loop.h>
38#include <private/android_filesystem_config.h>
39#include <cutils/partition_utils.h>
40#include <cutils/properties.h>
41#include <logwrap/logwrap.h>
42
43#include "mincrypt/rsa.h"
44#include "mincrypt/sha.h"
45#include "mincrypt/sha256.h"
46
47#include "fs_mgr_priv.h"
48#include "fs_mgr_priv_verity.h"
49
50#define KEY_LOC_PROP   "ro.crypto.keyfile.userdata"
51#define KEY_IN_FOOTER  "footer"
52
53#define E2FSCK_BIN      "/system/bin/e2fsck"
54#define MKSWAP_BIN      "/system/bin/mkswap"
55
56#define FSCK_LOG_FILE   "/dev/fscklogs/log"
57
58#define ZRAM_CONF_DEV   "/sys/block/zram0/disksize"
59
60#define ARRAY_SIZE(a) (sizeof(a) / sizeof(*(a)))
61
62struct flag_list {
63    const char *name;
64    unsigned flag;
65};
66
67static struct flag_list mount_flags[] = {
68    { "noatime",    MS_NOATIME },
69    { "noexec",     MS_NOEXEC },
70    { "nosuid",     MS_NOSUID },
71    { "nodev",      MS_NODEV },
72    { "nodiratime", MS_NODIRATIME },
73    { "ro",         MS_RDONLY },
74    { "rw",         0 },
75    { "remount",    MS_REMOUNT },
76    { "bind",       MS_BIND },
77    { "rec",        MS_REC },
78    { "unbindable", MS_UNBINDABLE },
79    { "private",    MS_PRIVATE },
80    { "slave",      MS_SLAVE },
81    { "shared",     MS_SHARED },
82    { "defaults",   0 },
83    { 0,            0 },
84};
85
86static struct flag_list fs_mgr_flags[] = {
87    { "wait",        MF_WAIT },
88    { "check",       MF_CHECK },
89    { "encryptable=",MF_CRYPT },
90    { "nonremovable",MF_NONREMOVABLE },
91    { "voldmanaged=",MF_VOLDMANAGED},
92    { "length=",     MF_LENGTH },
93    { "recoveryonly",MF_RECOVERYONLY },
94    { "swapprio=",   MF_SWAPPRIO },
95    { "zramsize=",   MF_ZRAMSIZE },
96    { "verify",      MF_VERIFY },
97    { "noemulatedsd", MF_NOEMULATEDSD },
98    { "defaults",    0 },
99    { 0,             0 },
100};
101
102struct fs_mgr_flag_values {
103    char *key_loc;
104    long long part_length;
105    char *label;
106    int partnum;
107    int swap_prio;
108    unsigned int zram_size;
109};
110
111/*
112 * gettime() - returns the time in seconds of the system's monotonic clock or
113 * zero on error.
114 */
115static time_t gettime(void)
116{
117    struct timespec ts;
118    int ret;
119
120    ret = clock_gettime(CLOCK_MONOTONIC, &ts);
121    if (ret < 0) {
122        ERROR("clock_gettime(CLOCK_MONOTONIC) failed: %s\n", strerror(errno));
123        return 0;
124    }
125
126    return ts.tv_sec;
127}
128
129static int wait_for_file(const char *filename, int timeout)
130{
131    struct stat info;
132    time_t timeout_time = gettime() + timeout;
133    int ret = -1;
134
135    while (gettime() < timeout_time && ((ret = stat(filename, &info)) < 0))
136        usleep(10000);
137
138    return ret;
139}
140
141static int parse_flags(char *flags, struct flag_list *fl,
142                       struct fs_mgr_flag_values *flag_vals,
143                       char *fs_options, int fs_options_len)
144{
145    int f = 0;
146    int i;
147    char *p;
148    char *savep;
149
150    /* initialize flag values.  If we find a relevant flag, we'll
151     * update the value */
152    if (flag_vals) {
153        memset(flag_vals, 0, sizeof(*flag_vals));
154        flag_vals->partnum = -1;
155        flag_vals->swap_prio = -1; /* negative means it wasn't specified. */
156    }
157
158    /* initialize fs_options to the null string */
159    if (fs_options && (fs_options_len > 0)) {
160        fs_options[0] = '\0';
161    }
162
163    p = strtok_r(flags, ",", &savep);
164    while (p) {
165        /* Look for the flag "p" in the flag list "fl"
166         * If not found, the loop exits with fl[i].name being null.
167         */
168        for (i = 0; fl[i].name; i++) {
169            if (!strncmp(p, fl[i].name, strlen(fl[i].name))) {
170                f |= fl[i].flag;
171                if ((fl[i].flag == MF_CRYPT) && flag_vals) {
172                    /* The encryptable flag is followed by an = and the
173                     * location of the keys.  Get it and return it.
174                     */
175                    flag_vals->key_loc = strdup(strchr(p, '=') + 1);
176                } else if ((fl[i].flag == MF_LENGTH) && flag_vals) {
177                    /* The length flag is followed by an = and the
178                     * size of the partition.  Get it and return it.
179                     */
180                    flag_vals->part_length = strtoll(strchr(p, '=') + 1, NULL, 0);
181                } else if ((fl[i].flag == MF_VOLDMANAGED) && flag_vals) {
182                    /* The voldmanaged flag is followed by an = and the
183                     * label, a colon and the partition number or the
184                     * word "auto", e.g.
185                     *   voldmanaged=sdcard:3
186                     * Get and return them.
187                     */
188                    char *label_start;
189                    char *label_end;
190                    char *part_start;
191
192                    label_start = strchr(p, '=') + 1;
193                    label_end = strchr(p, ':');
194                    if (label_end) {
195                        flag_vals->label = strndup(label_start,
196                                                   (int) (label_end - label_start));
197                        part_start = strchr(p, ':') + 1;
198                        if (!strcmp(part_start, "auto")) {
199                            flag_vals->partnum = -1;
200                        } else {
201                            flag_vals->partnum = strtol(part_start, NULL, 0);
202                        }
203                    } else {
204                        ERROR("Warning: voldmanaged= flag malformed\n");
205                    }
206                } else if ((fl[i].flag == MF_SWAPPRIO) && flag_vals) {
207                    flag_vals->swap_prio = strtoll(strchr(p, '=') + 1, NULL, 0);
208                } else if ((fl[i].flag == MF_ZRAMSIZE) && flag_vals) {
209                    flag_vals->zram_size = strtoll(strchr(p, '=') + 1, NULL, 0);
210                }
211                break;
212            }
213        }
214
215        if (!fl[i].name) {
216            if (fs_options) {
217                /* It's not a known flag, so it must be a filesystem specific
218                 * option.  Add it to fs_options if it was passed in.
219                 */
220                strlcat(fs_options, p, fs_options_len);
221                strlcat(fs_options, ",", fs_options_len);
222            } else {
223                /* fs_options was not passed in, so if the flag is unknown
224                 * it's an error.
225                 */
226                ERROR("Warning: unknown flag %s\n", p);
227            }
228        }
229        p = strtok_r(NULL, ",", &savep);
230    }
231
232out:
233    if (fs_options && fs_options[0]) {
234        /* remove the last trailing comma from the list of options */
235        fs_options[strlen(fs_options) - 1] = '\0';
236    }
237
238    return f;
239}
240
241/* Read a line of text till the next newline character.
242 * If no newline is found before the buffer is full, continue reading till a new line is seen,
243 * then return an empty buffer.  This effectively ignores lines that are too long.
244 * On EOF, return null.
245 */
246static char *fs_getline(char *buf, int size, FILE *file)
247{
248    int cnt = 0;
249    int eof = 0;
250    int eol = 0;
251    int c;
252
253    if (size < 1) {
254        return NULL;
255    }
256
257    while (cnt < (size - 1)) {
258        c = getc(file);
259        if (c == EOF) {
260            eof = 1;
261            break;
262        }
263
264        *(buf + cnt) = c;
265        cnt++;
266
267        if (c == '\n') {
268            eol = 1;
269            break;
270        }
271    }
272
273    /* Null terminate what we've read */
274    *(buf + cnt) = '\0';
275
276    if (eof) {
277        if (cnt) {
278            return buf;
279        } else {
280            return NULL;
281        }
282    } else if (eol) {
283        return buf;
284    } else {
285        /* The line is too long.  Read till a newline or EOF.
286         * If EOF, return null, if newline, return an empty buffer.
287         */
288        while(1) {
289            c = getc(file);
290            if (c == EOF) {
291                return NULL;
292            } else if (c == '\n') {
293                *buf = '\0';
294                return buf;
295            }
296        }
297    }
298}
299
300struct fstab *fs_mgr_read_fstab(const char *fstab_path)
301{
302    FILE *fstab_file;
303    int cnt, entries;
304    int len;
305    char line[256];
306    const char *delim = " \t";
307    char *save_ptr, *p;
308    struct fstab *fstab;
309    struct fstab_rec *recs;
310    struct fs_mgr_flag_values flag_vals;
311#define FS_OPTIONS_LEN 1024
312    char tmp_fs_options[FS_OPTIONS_LEN];
313
314    fstab_file = fopen(fstab_path, "r");
315    if (!fstab_file) {
316        ERROR("Cannot open file %s\n", fstab_path);
317        return 0;
318    }
319
320    entries = 0;
321    while (fs_getline(line, sizeof(line), fstab_file)) {
322        /* if the last character is a newline, shorten the string by 1 byte */
323        len = strlen(line);
324        if (line[len - 1] == '\n') {
325            line[len - 1] = '\0';
326        }
327        /* Skip any leading whitespace */
328        p = line;
329        while (isspace(*p)) {
330            p++;
331        }
332        /* ignore comments or empty lines */
333        if (*p == '#' || *p == '\0')
334            continue;
335        entries++;
336    }
337
338    if (!entries) {
339        ERROR("No entries found in fstab\n");
340        return 0;
341    }
342
343    /* Allocate and init the fstab structure */
344    fstab = calloc(1, sizeof(struct fstab));
345    fstab->num_entries = entries;
346    fstab->fstab_filename = strdup(fstab_path);
347    fstab->recs = calloc(fstab->num_entries, sizeof(struct fstab_rec));
348
349    fseek(fstab_file, 0, SEEK_SET);
350
351    cnt = 0;
352    while (fs_getline(line, sizeof(line), fstab_file)) {
353        /* if the last character is a newline, shorten the string by 1 byte */
354        len = strlen(line);
355        if (line[len - 1] == '\n') {
356            line[len - 1] = '\0';
357        }
358
359        /* Skip any leading whitespace */
360        p = line;
361        while (isspace(*p)) {
362            p++;
363        }
364        /* ignore comments or empty lines */
365        if (*p == '#' || *p == '\0')
366            continue;
367
368        /* If a non-comment entry is greater than the size we allocated, give an
369         * error and quit.  This can happen in the unlikely case the file changes
370         * between the two reads.
371         */
372        if (cnt >= entries) {
373            ERROR("Tried to process more entries than counted\n");
374            break;
375        }
376
377        if (!(p = strtok_r(line, delim, &save_ptr))) {
378            ERROR("Error parsing mount source\n");
379            return 0;
380        }
381        fstab->recs[cnt].blk_device = strdup(p);
382
383        if (!(p = strtok_r(NULL, delim, &save_ptr))) {
384            ERROR("Error parsing mount_point\n");
385            return 0;
386        }
387        fstab->recs[cnt].mount_point = strdup(p);
388
389        if (!(p = strtok_r(NULL, delim, &save_ptr))) {
390            ERROR("Error parsing fs_type\n");
391            return 0;
392        }
393        fstab->recs[cnt].fs_type = strdup(p);
394
395        if (!(p = strtok_r(NULL, delim, &save_ptr))) {
396            ERROR("Error parsing mount_flags\n");
397            return 0;
398        }
399        tmp_fs_options[0] = '\0';
400        fstab->recs[cnt].flags = parse_flags(p, mount_flags, NULL,
401                                       tmp_fs_options, FS_OPTIONS_LEN);
402
403        /* fs_options are optional */
404        if (tmp_fs_options[0]) {
405            fstab->recs[cnt].fs_options = strdup(tmp_fs_options);
406        } else {
407            fstab->recs[cnt].fs_options = NULL;
408        }
409
410        if (!(p = strtok_r(NULL, delim, &save_ptr))) {
411            ERROR("Error parsing fs_mgr_options\n");
412            return 0;
413        }
414        fstab->recs[cnt].fs_mgr_flags = parse_flags(p, fs_mgr_flags,
415                                                    &flag_vals, NULL, 0);
416        fstab->recs[cnt].key_loc = flag_vals.key_loc;
417        fstab->recs[cnt].length = flag_vals.part_length;
418        fstab->recs[cnt].label = flag_vals.label;
419        fstab->recs[cnt].partnum = flag_vals.partnum;
420        fstab->recs[cnt].swap_prio = flag_vals.swap_prio;
421        fstab->recs[cnt].zram_size = flag_vals.zram_size;
422        cnt++;
423    }
424    fclose(fstab_file);
425
426    return fstab;
427}
428
429void fs_mgr_free_fstab(struct fstab *fstab)
430{
431    int i;
432
433    if (!fstab) {
434        return;
435    }
436
437    for (i = 0; i < fstab->num_entries; i++) {
438        /* Free the pointers return by strdup(3) */
439        free(fstab->recs[i].blk_device);
440        free(fstab->recs[i].mount_point);
441        free(fstab->recs[i].fs_type);
442        free(fstab->recs[i].fs_options);
443        free(fstab->recs[i].key_loc);
444        free(fstab->recs[i].label);
445        i++;
446    }
447
448    /* Free the fstab_recs array created by calloc(3) */
449    free(fstab->recs);
450
451    /* Free the fstab filename */
452    free(fstab->fstab_filename);
453
454    /* Free fstab */
455    free(fstab);
456}
457
458static void check_fs(char *blk_device, char *fs_type, char *target)
459{
460    int status;
461    int ret;
462    long tmpmnt_flags = MS_NOATIME | MS_NOEXEC | MS_NOSUID;
463    char *tmpmnt_opts = "nomblk_io_submit,errors=remount-ro";
464    char *e2fsck_argv[] = {
465        E2FSCK_BIN,
466        "-y",
467        blk_device
468    };
469
470    /* Check for the types of filesystems we know how to check */
471    if (!strcmp(fs_type, "ext2") || !strcmp(fs_type, "ext3") || !strcmp(fs_type, "ext4")) {
472        /*
473         * First try to mount and unmount the filesystem.  We do this because
474         * the kernel is more efficient than e2fsck in running the journal and
475         * processing orphaned inodes, and on at least one device with a
476         * performance issue in the emmc firmware, it can take e2fsck 2.5 minutes
477         * to do what the kernel does in about a second.
478         *
479         * After mounting and unmounting the filesystem, run e2fsck, and if an
480         * error is recorded in the filesystem superblock, e2fsck will do a full
481         * check.  Otherwise, it does nothing.  If the kernel cannot mount the
482         * filesytsem due to an error, e2fsck is still run to do a full check
483         * fix the filesystem.
484         */
485        ret = mount(blk_device, target, fs_type, tmpmnt_flags, tmpmnt_opts);
486        if (!ret) {
487            umount(target);
488        }
489
490        INFO("Running %s on %s\n", E2FSCK_BIN, blk_device);
491
492        ret = android_fork_execvp_ext(ARRAY_SIZE(e2fsck_argv), e2fsck_argv,
493                                      &status, true, LOG_KLOG | LOG_FILE,
494                                      true, FSCK_LOG_FILE);
495
496        if (ret < 0) {
497            /* No need to check for error in fork, we can't really handle it now */
498            ERROR("Failed trying to run %s\n", E2FSCK_BIN);
499        }
500    }
501
502    return;
503}
504
505static void remove_trailing_slashes(char *n)
506{
507    int len;
508
509    len = strlen(n) - 1;
510    while ((*(n + len) == '/') && len) {
511      *(n + len) = '\0';
512      len--;
513    }
514}
515
516/*
517 * Mark the given block device as read-only, using the BLKROSET ioctl.
518 * Return 0 on success, and -1 on error.
519 */
520static void fs_set_blk_ro(const char *blockdev)
521{
522    int fd;
523    int ON = 1;
524
525    fd = open(blockdev, O_RDONLY);
526    if (fd < 0) {
527        // should never happen
528        return;
529    }
530
531    ioctl(fd, BLKROSET, &ON);
532    close(fd);
533}
534
535/*
536 * __mount(): wrapper around the mount() system call which also
537 * sets the underlying block device to read-only if the mount is read-only.
538 * See "man 2 mount" for return values.
539 */
540static int __mount(const char *source, const char *target,
541                   const char *filesystemtype, unsigned long mountflags,
542                   const void *data)
543{
544    int ret = mount(source, target, filesystemtype, mountflags, data);
545
546    if ((ret == 0) && (mountflags & MS_RDONLY) != 0) {
547        fs_set_blk_ro(source);
548    }
549
550    return ret;
551}
552
553static int fs_match(char *in1, char *in2)
554{
555    char *n1;
556    char *n2;
557    int ret;
558
559    n1 = strdup(in1);
560    n2 = strdup(in2);
561
562    remove_trailing_slashes(n1);
563    remove_trailing_slashes(n2);
564
565    ret = !strcmp(n1, n2);
566
567    free(n1);
568    free(n2);
569
570    return ret;
571}
572
573int fs_mgr_mount_all(struct fstab *fstab)
574{
575    int i = 0;
576    int encrypted = 0;
577    int ret = -1;
578    int mret;
579
580    if (!fstab) {
581        return ret;
582    }
583
584    for (i = 0; i < fstab->num_entries; i++) {
585        /* Don't mount entries that are managed by vold */
586        if (fstab->recs[i].fs_mgr_flags & (MF_VOLDMANAGED | MF_RECOVERYONLY)) {
587            continue;
588        }
589
590        /* Skip swap and raw partition entries such as boot, recovery, etc */
591        if (!strcmp(fstab->recs[i].fs_type, "swap") ||
592            !strcmp(fstab->recs[i].fs_type, "emmc") ||
593            !strcmp(fstab->recs[i].fs_type, "mtd")) {
594            continue;
595        }
596
597        if (fstab->recs[i].fs_mgr_flags & MF_WAIT) {
598            wait_for_file(fstab->recs[i].blk_device, WAIT_TIMEOUT);
599        }
600
601        if (fstab->recs[i].fs_mgr_flags & MF_CHECK) {
602            check_fs(fstab->recs[i].blk_device, fstab->recs[i].fs_type,
603                     fstab->recs[i].mount_point);
604        }
605
606        if (fstab->recs[i].fs_mgr_flags & MF_VERIFY) {
607            if (fs_mgr_setup_verity(&fstab->recs[i]) < 0) {
608                ERROR("Could not set up verified partition, skipping!");
609                continue;
610            }
611        }
612
613        mret = __mount(fstab->recs[i].blk_device, fstab->recs[i].mount_point,
614                     fstab->recs[i].fs_type, fstab->recs[i].flags,
615                     fstab->recs[i].fs_options);
616
617        if (!mret) {
618            /* Success!  Go get the next one */
619            continue;
620        }
621
622        /* mount(2) returned an error, check if it's encrypted and deal with it */
623        if ((fstab->recs[i].fs_mgr_flags & MF_CRYPT) &&
624            !partition_wiped(fstab->recs[i].blk_device)) {
625            /* Need to mount a tmpfs at this mountpoint for now, and set
626             * properties that vold will query later for decrypting
627             */
628            if (mount("tmpfs", fstab->recs[i].mount_point, "tmpfs",
629                  MS_NOATIME | MS_NOSUID | MS_NODEV, CRYPTO_TMPFS_OPTIONS) < 0) {
630                ERROR("Cannot mount tmpfs filesystem for encrypted fs at %s\n",
631                        fstab->recs[i].mount_point);
632                goto out;
633            }
634            encrypted = 1;
635        } else {
636            ERROR("Cannot mount filesystem on %s at %s\n",
637                    fstab->recs[i].blk_device, fstab->recs[i].mount_point);
638            goto out;
639        }
640    }
641
642    if (encrypted) {
643        ret = 1;
644    } else {
645        ret = 0;
646    }
647
648out:
649    return ret;
650}
651
652/* If tmp_mount_point is non-null, mount the filesystem there.  This is for the
653 * tmp mount we do to check the user password
654 */
655int fs_mgr_do_mount(struct fstab *fstab, char *n_name, char *n_blk_device,
656                    char *tmp_mount_point)
657{
658    int i = 0;
659    int ret = -1;
660    char *m;
661
662    if (!fstab) {
663        return ret;
664    }
665
666    for (i = 0; i < fstab->num_entries; i++) {
667        if (!fs_match(fstab->recs[i].mount_point, n_name)) {
668            continue;
669        }
670
671        /* We found our match */
672        /* If this swap or a raw partition, report an error */
673        if (!strcmp(fstab->recs[i].fs_type, "swap") ||
674            !strcmp(fstab->recs[i].fs_type, "emmc") ||
675            !strcmp(fstab->recs[i].fs_type, "mtd")) {
676            ERROR("Cannot mount filesystem of type %s on %s\n",
677                  fstab->recs[i].fs_type, n_blk_device);
678            goto out;
679        }
680
681        /* First check the filesystem if requested */
682        if (fstab->recs[i].fs_mgr_flags & MF_WAIT) {
683            wait_for_file(n_blk_device, WAIT_TIMEOUT);
684        }
685
686        if (fstab->recs[i].fs_mgr_flags & MF_CHECK) {
687            check_fs(n_blk_device, fstab->recs[i].fs_type,
688                     fstab->recs[i].mount_point);
689        }
690
691        if (fstab->recs[i].fs_mgr_flags & MF_VERIFY) {
692            if (fs_mgr_setup_verity(&fstab->recs[i]) < 0) {
693                ERROR("Could not set up verified partition, skipping!");
694                continue;
695            }
696        }
697
698        /* Now mount it where requested */
699        if (tmp_mount_point) {
700            m = tmp_mount_point;
701        } else {
702            m = fstab->recs[i].mount_point;
703        }
704        if (__mount(n_blk_device, m, fstab->recs[i].fs_type,
705                    fstab->recs[i].flags, fstab->recs[i].fs_options)) {
706            ERROR("Cannot mount filesystem on %s at %s\n",
707                    n_blk_device, m);
708            goto out;
709        } else {
710            ret = 0;
711            goto out;
712        }
713    }
714
715    /* We didn't find a match, say so and return an error */
716    ERROR("Cannot find mount point %s in fstab\n", fstab->recs[i].mount_point);
717
718out:
719    return ret;
720}
721
722/*
723 * mount a tmpfs filesystem at the given point.
724 * return 0 on success, non-zero on failure.
725 */
726int fs_mgr_do_tmpfs_mount(char *n_name)
727{
728    int ret;
729
730    ret = mount("tmpfs", n_name, "tmpfs",
731                MS_NOATIME | MS_NOSUID | MS_NODEV, CRYPTO_TMPFS_OPTIONS);
732    if (ret < 0) {
733        ERROR("Cannot mount tmpfs filesystem at %s\n", n_name);
734        return -1;
735    }
736
737    /* Success */
738    return 0;
739}
740
741int fs_mgr_unmount_all(struct fstab *fstab)
742{
743    int i = 0;
744    int ret = 0;
745
746    if (!fstab) {
747        return -1;
748    }
749
750    while (fstab->recs[i].blk_device) {
751        if (umount(fstab->recs[i].mount_point)) {
752            ERROR("Cannot unmount filesystem at %s\n", fstab->recs[i].mount_point);
753            ret = -1;
754        }
755        i++;
756    }
757
758    return ret;
759}
760
761/* This must be called after mount_all, because the mkswap command needs to be
762 * available.
763 */
764int fs_mgr_swapon_all(struct fstab *fstab)
765{
766    int i = 0;
767    int flags = 0;
768    int err = 0;
769    int ret = 0;
770    int status;
771    char *mkswap_argv[2] = {
772        MKSWAP_BIN,
773        NULL
774    };
775
776    if (!fstab) {
777        return -1;
778    }
779
780    for (i = 0; i < fstab->num_entries; i++) {
781        /* Skip non-swap entries */
782        if (strcmp(fstab->recs[i].fs_type, "swap")) {
783            continue;
784        }
785
786        if (fstab->recs[i].zram_size > 0) {
787            /* A zram_size was specified, so we need to configure the
788             * device.  There is no point in having multiple zram devices
789             * on a system (all the memory comes from the same pool) so
790             * we can assume the device number is 0.
791             */
792            FILE *zram_fp;
793
794            zram_fp = fopen(ZRAM_CONF_DEV, "r+");
795            if (zram_fp == NULL) {
796                ERROR("Unable to open zram conf device " ZRAM_CONF_DEV);
797                ret = -1;
798                continue;
799            }
800            fprintf(zram_fp, "%d\n", fstab->recs[i].zram_size);
801            fclose(zram_fp);
802        }
803
804        if (fstab->recs[i].fs_mgr_flags & MF_WAIT) {
805            wait_for_file(fstab->recs[i].blk_device, WAIT_TIMEOUT);
806        }
807
808        /* Initialize the swap area */
809        mkswap_argv[1] = fstab->recs[i].blk_device;
810        err = android_fork_execvp_ext(ARRAY_SIZE(mkswap_argv), mkswap_argv,
811                                      &status, true, LOG_KLOG, false, NULL);
812        if (err) {
813            ERROR("mkswap failed for %s\n", fstab->recs[i].blk_device);
814            ret = -1;
815            continue;
816        }
817
818        /* If -1, then no priority was specified in fstab, so don't set
819         * SWAP_FLAG_PREFER or encode the priority */
820        if (fstab->recs[i].swap_prio >= 0) {
821            flags = (fstab->recs[i].swap_prio << SWAP_FLAG_PRIO_SHIFT) &
822                    SWAP_FLAG_PRIO_MASK;
823            flags |= SWAP_FLAG_PREFER;
824        } else {
825            flags = 0;
826        }
827        err = swapon(fstab->recs[i].blk_device, flags);
828        if (err) {
829            ERROR("swapon failed for %s\n", fstab->recs[i].blk_device);
830            ret = -1;
831        }
832    }
833
834    return ret;
835}
836
837/*
838 * key_loc must be at least PROPERTY_VALUE_MAX bytes long
839 *
840 * real_blk_device must be at least PROPERTY_VALUE_MAX bytes long
841 */
842int fs_mgr_get_crypt_info(struct fstab *fstab, char *key_loc, char *real_blk_device, int size)
843{
844    int i = 0;
845
846    if (!fstab) {
847        return -1;
848    }
849    /* Initialize return values to null strings */
850    if (key_loc) {
851        *key_loc = '\0';
852    }
853    if (real_blk_device) {
854        *real_blk_device = '\0';
855    }
856
857    /* Look for the encryptable partition to find the data */
858    for (i = 0; i < fstab->num_entries; i++) {
859        /* Don't deal with vold managed enryptable partitions here */
860        if (fstab->recs[i].fs_mgr_flags & MF_VOLDMANAGED) {
861            continue;
862        }
863        if (!(fstab->recs[i].fs_mgr_flags & MF_CRYPT)) {
864            continue;
865        }
866
867        /* We found a match */
868        if (key_loc) {
869            strlcpy(key_loc, fstab->recs[i].key_loc, size);
870        }
871        if (real_blk_device) {
872            strlcpy(real_blk_device, fstab->recs[i].blk_device, size);
873        }
874        break;
875    }
876
877    return 0;
878}
879
880/* Add an entry to the fstab, and return 0 on success or -1 on error */
881int fs_mgr_add_entry(struct fstab *fstab,
882                     const char *mount_point, const char *fs_type,
883                     const char *blk_device, long long length)
884{
885    struct fstab_rec *new_fstab_recs;
886    int n = fstab->num_entries;
887
888    new_fstab_recs = (struct fstab_rec *)
889                     realloc(fstab->recs, sizeof(struct fstab_rec) * (n + 1));
890
891    if (!new_fstab_recs) {
892        return -1;
893    }
894
895    /* A new entry was added, so initialize it */
896     memset(&new_fstab_recs[n], 0, sizeof(struct fstab_rec));
897     new_fstab_recs[n].mount_point = strdup(mount_point);
898     new_fstab_recs[n].fs_type = strdup(fs_type);
899     new_fstab_recs[n].blk_device = strdup(blk_device);
900     new_fstab_recs[n].length = 0;
901
902     /* Update the fstab struct */
903     fstab->recs = new_fstab_recs;
904     fstab->num_entries++;
905
906     return 0;
907}
908
909struct fstab_rec *fs_mgr_get_entry_for_mount_point(struct fstab *fstab, const char *path)
910{
911    int i;
912
913    if (!fstab) {
914        return NULL;
915    }
916
917    for (i = 0; i < fstab->num_entries; i++) {
918        int len = strlen(fstab->recs[i].mount_point);
919        if (strncmp(path, fstab->recs[i].mount_point, len) == 0 &&
920            (path[len] == '\0' || path[len] == '/')) {
921            return &fstab->recs[i];
922        }
923    }
924
925    return NULL;
926}
927
928int fs_mgr_is_voldmanaged(struct fstab_rec *fstab)
929{
930    return fstab->fs_mgr_flags & MF_VOLDMANAGED;
931}
932
933int fs_mgr_is_nonremovable(struct fstab_rec *fstab)
934{
935    return fstab->fs_mgr_flags & MF_NONREMOVABLE;
936}
937
938int fs_mgr_is_encryptable(struct fstab_rec *fstab)
939{
940    return fstab->fs_mgr_flags & MF_CRYPT;
941}
942
943int fs_mgr_is_noemulatedsd(struct fstab_rec *fstab)
944{
945    return fstab->fs_mgr_flags & MF_NOEMULATEDSD;
946}
947