builtins.c revision 25383a5da2ce4ada76df46e1bc7ae56ac0e41fc4 
1/*
2 * Copyright (C) 2008 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 <sys/types.h>
18#include <sys/stat.h>
19#include <fcntl.h>
20#include <unistd.h>
21#include <string.h>
22#include <stdio.h>
23#include <linux/kd.h>
24#include <errno.h>
25#include <sys/socket.h>
26#include <netinet/in.h>
27#include <linux/if.h>
28#include <arpa/inet.h>
29#include <stdlib.h>
30#include <sys/mount.h>
31#include <sys/resource.h>
32#include <sys/wait.h>
33#include <linux/loop.h>
34#include <cutils/partition_utils.h>
35#include <cutils/android_reboot.h>
36#include <sys/system_properties.h>
37#include <fs_mgr.h>
38
39#include <selinux/selinux.h>
40#include <selinux/label.h>
41
42#include "init.h"
43#include "keywords.h"
44#include "property_service.h"
45#include "devices.h"
46#include "init_parser.h"
47#include "util.h"
48#include "log.h"
49
50#include <private/android_filesystem_config.h>
51
52void add_environment(const char *name, const char *value);
53
54extern int init_module(void *, unsigned long, const char *);
55
56static int write_file(const char *path, const char *value)
57{
58    int fd, ret, len;
59
60    fd = open(path, O_WRONLY|O_CREAT, 0622);
61
62    if (fd < 0)
63        return -errno;
64
65    len = strlen(value);
66
67    do {
68        ret = write(fd, value, len);
69    } while (ret < 0 && errno == EINTR);
70
71    close(fd);
72    if (ret < 0) {
73        return -errno;
74    } else {
75        return 0;
76    }
77}
78
79static int _open(const char *path)
80{
81    int fd;
82
83    fd = open(path, O_RDONLY | O_NOFOLLOW);
84    if (fd < 0)
85        fd = open(path, O_WRONLY | O_NOFOLLOW);
86
87    return fd;
88}
89
90static int _chown(const char *path, unsigned int uid, unsigned int gid)
91{
92    int fd;
93    int ret;
94
95    fd = _open(path);
96    if (fd < 0) {
97        return -1;
98    }
99
100    ret = fchown(fd, uid, gid);
101    if (ret < 0) {
102        int errno_copy = errno;
103        close(fd);
104        errno = errno_copy;
105        return -1;
106    }
107
108    close(fd);
109
110    return 0;
111}
112
113static int _chmod(const char *path, mode_t mode)
114{
115    int fd;
116    int ret;
117
118    fd = _open(path);
119    if (fd < 0) {
120        return -1;
121    }
122
123    ret = fchmod(fd, mode);
124    if (ret < 0) {
125        int errno_copy = errno;
126        close(fd);
127        errno = errno_copy;
128        return -1;
129    }
130
131    close(fd);
132
133    return 0;
134}
135
136static int insmod(const char *filename, char *options)
137{
138    void *module;
139    unsigned size;
140    int ret;
141
142    module = read_file(filename, &size);
143    if (!module)
144        return -1;
145
146    ret = init_module(module, size, options);
147
148    free(module);
149
150    return ret;
151}
152
153static int setkey(struct kbentry *kbe)
154{
155    int fd, ret;
156
157    fd = open("/dev/tty0", O_RDWR | O_SYNC);
158    if (fd < 0)
159        return -1;
160
161    ret = ioctl(fd, KDSKBENT, kbe);
162
163    close(fd);
164    return ret;
165}
166
167static int __ifupdown(const char *interface, int up)
168{
169    struct ifreq ifr;
170    int s, ret;
171
172    strlcpy(ifr.ifr_name, interface, IFNAMSIZ);
173
174    s = socket(AF_INET, SOCK_DGRAM, 0);
175    if (s < 0)
176        return -1;
177
178    ret = ioctl(s, SIOCGIFFLAGS, &ifr);
179    if (ret < 0) {
180        goto done;
181    }
182
183    if (up)
184        ifr.ifr_flags |= IFF_UP;
185    else
186        ifr.ifr_flags &= ~IFF_UP;
187
188    ret = ioctl(s, SIOCSIFFLAGS, &ifr);
189
190done:
191    close(s);
192    return ret;
193}
194
195static void service_start_if_not_disabled(struct service *svc)
196{
197    if (!(svc->flags & SVC_DISABLED)) {
198        service_start(svc, NULL);
199    }
200}
201
202int do_chdir(int nargs, char **args)
203{
204    chdir(args[1]);
205    return 0;
206}
207
208int do_chroot(int nargs, char **args)
209{
210    chroot(args[1]);
211    return 0;
212}
213
214int do_class_start(int nargs, char **args)
215{
216        /* Starting a class does not start services
217         * which are explicitly disabled.  They must
218         * be started individually.
219         */
220    service_for_each_class(args[1], service_start_if_not_disabled);
221    return 0;
222}
223
224int do_class_stop(int nargs, char **args)
225{
226    service_for_each_class(args[1], service_stop);
227    return 0;
228}
229
230int do_class_reset(int nargs, char **args)
231{
232    service_for_each_class(args[1], service_reset);
233    return 0;
234}
235
236int do_domainname(int nargs, char **args)
237{
238    return write_file("/proc/sys/kernel/domainname", args[1]);
239}
240
241int do_exec(int nargs, char **args)
242{
243    return -1;
244}
245
246int do_export(int nargs, char **args)
247{
248    add_environment(args[1], args[2]);
249    return 0;
250}
251
252int do_hostname(int nargs, char **args)
253{
254    return write_file("/proc/sys/kernel/hostname", args[1]);
255}
256
257int do_ifup(int nargs, char **args)
258{
259    return __ifupdown(args[1], 1);
260}
261
262
263static int do_insmod_inner(int nargs, char **args, int opt_len)
264{
265    char options[opt_len + 1];
266    int i;
267
268    options[0] = '\0';
269    if (nargs > 2) {
270        strcpy(options, args[2]);
271        for (i = 3; i < nargs; ++i) {
272            strcat(options, " ");
273            strcat(options, args[i]);
274        }
275    }
276
277    return insmod(args[1], options);
278}
279
280int do_insmod(int nargs, char **args)
281{
282    int i;
283    int size = 0;
284
285    if (nargs > 2) {
286        for (i = 2; i < nargs; ++i)
287            size += strlen(args[i]) + 1;
288    }
289
290    return do_insmod_inner(nargs, args, size);
291}
292
293int do_mkdir(int nargs, char **args)
294{
295    mode_t mode = 0755;
296    int ret;
297
298    /* mkdir <path> [mode] [owner] [group] */
299
300    if (nargs >= 3) {
301        mode = strtoul(args[2], 0, 8);
302    }
303
304    ret = make_dir(args[1], mode);
305    /* chmod in case the directory already exists */
306    if (ret == -1 && errno == EEXIST) {
307        ret = _chmod(args[1], mode);
308    }
309    if (ret == -1) {
310        return -errno;
311    }
312
313    if (nargs >= 4) {
314        uid_t uid = decode_uid(args[3]);
315        gid_t gid = -1;
316
317        if (nargs == 5) {
318            gid = decode_uid(args[4]);
319        }
320
321        if (_chown(args[1], uid, gid) < 0) {
322            return -errno;
323        }
324
325        /* chown may have cleared S_ISUID and S_ISGID, chmod again */
326        if (mode & (S_ISUID | S_ISGID)) {
327            ret = _chmod(args[1], mode);
328            if (ret == -1) {
329                return -errno;
330            }
331        }
332    }
333
334    return 0;
335}
336
337static struct {
338    const char *name;
339    unsigned flag;
340} mount_flags[] = {
341    { "noatime",    MS_NOATIME },
342    { "noexec",     MS_NOEXEC },
343    { "nosuid",     MS_NOSUID },
344    { "nodev",      MS_NODEV },
345    { "nodiratime", MS_NODIRATIME },
346    { "ro",         MS_RDONLY },
347    { "rw",         0 },
348    { "remount",    MS_REMOUNT },
349    { "bind",       MS_BIND },
350    { "rec",        MS_REC },
351    { "unbindable", MS_UNBINDABLE },
352    { "private",    MS_PRIVATE },
353    { "slave",      MS_SLAVE },
354    { "shared",     MS_SHARED },
355    { "defaults",   0 },
356    { 0,            0 },
357};
358
359#define DATA_MNT_POINT "/data"
360
361/* mount <type> <device> <path> <flags ...> <options> */
362int do_mount(int nargs, char **args)
363{
364    char tmp[64];
365    char *source, *target, *system;
366    char *options = NULL;
367    unsigned flags = 0;
368    int n, i;
369    int wait = 0;
370
371    for (n = 4; n < nargs; n++) {
372        for (i = 0; mount_flags[i].name; i++) {
373            if (!strcmp(args[n], mount_flags[i].name)) {
374                flags |= mount_flags[i].flag;
375                break;
376            }
377        }
378
379        if (!mount_flags[i].name) {
380            if (!strcmp(args[n], "wait"))
381                wait = 1;
382            /* if our last argument isn't a flag, wolf it up as an option string */
383            else if (n + 1 == nargs)
384                options = args[n];
385        }
386    }
387
388    system = args[1];
389    source = args[2];
390    target = args[3];
391
392    if (!strncmp(source, "mtd@", 4)) {
393        n = mtd_name_to_number(source + 4);
394        if (n < 0) {
395            return -1;
396        }
397
398        sprintf(tmp, "/dev/block/mtdblock%d", n);
399
400        if (wait)
401            wait_for_file(tmp, COMMAND_RETRY_TIMEOUT);
402        if (mount(tmp, target, system, flags, options) < 0) {
403            return -1;
404        }
405
406        goto exit_success;
407    } else if (!strncmp(source, "loop@", 5)) {
408        int mode, loop, fd;
409        struct loop_info info;
410
411        mode = (flags & MS_RDONLY) ? O_RDONLY : O_RDWR;
412        fd = open(source + 5, mode);
413        if (fd < 0) {
414            return -1;
415        }
416
417        for (n = 0; ; n++) {
418            sprintf(tmp, "/dev/block/loop%d", n);
419            loop = open(tmp, mode);
420            if (loop < 0) {
421                return -1;
422            }
423
424            /* if it is a blank loop device */
425            if (ioctl(loop, LOOP_GET_STATUS, &info) < 0 && errno == ENXIO) {
426                /* if it becomes our loop device */
427                if (ioctl(loop, LOOP_SET_FD, fd) >= 0) {
428                    close(fd);
429
430                    if (mount(tmp, target, system, flags, options) < 0) {
431                        ioctl(loop, LOOP_CLR_FD, 0);
432                        close(loop);
433                        return -1;
434                    }
435
436                    close(loop);
437                    goto exit_success;
438                }
439            }
440
441            close(loop);
442        }
443
444        close(fd);
445        ERROR("out of loopback devices");
446        return -1;
447    } else {
448        if (wait)
449            wait_for_file(source, COMMAND_RETRY_TIMEOUT);
450        if (mount(source, target, system, flags, options) < 0) {
451            return -1;
452        }
453
454    }
455
456exit_success:
457    return 0;
458
459}
460
461int do_mount_all(int nargs, char **args)
462{
463    pid_t pid;
464    int ret = -1;
465    int child_ret = -1;
466    int status;
467    const char *prop;
468    struct fstab *fstab;
469
470    if (nargs != 2) {
471        return -1;
472    }
473
474    /*
475     * Call fs_mgr_mount_all() to mount all filesystems.  We fork(2) and
476     * do the call in the child to provide protection to the main init
477     * process if anything goes wrong (crash or memory leak), and wait for
478     * the child to finish in the parent.
479     */
480    pid = fork();
481    if (pid > 0) {
482        /* Parent.  Wait for the child to return */
483        waitpid(pid, &status, 0);
484        if (WIFEXITED(status)) {
485            ret = WEXITSTATUS(status);
486        } else {
487            ret = -1;
488        }
489    } else if (pid == 0) {
490        /* child, call fs_mgr_mount_all() */
491        klog_set_level(6);  /* So we can see what fs_mgr_mount_all() does */
492        fstab = fs_mgr_read_fstab(args[1]);
493        child_ret = fs_mgr_mount_all(fstab);
494        fs_mgr_free_fstab(fstab);
495        if (child_ret == -1) {
496            ERROR("fs_mgr_mount_all returned an error\n");
497        }
498        exit(child_ret);
499    } else {
500        /* fork failed, return an error */
501        return -1;
502    }
503
504    /* ret is 1 if the device is encrypted, 0 if not, and -1 on error */
505    if (ret == 1) {
506        property_set("ro.crypto.state", "encrypted");
507        property_set("vold.decrypt", "1");
508    } else if (ret == 0) {
509        property_set("ro.crypto.state", "unencrypted");
510        /* If fs_mgr determined this is an unencrypted device, then trigger
511         * that action.
512         */
513        action_for_each_trigger("nonencrypted", action_add_queue_tail);
514    }
515
516    return ret;
517}
518
519int do_setcon(int nargs, char **args) {
520    if (is_selinux_enabled() <= 0)
521        return 0;
522    if (setcon(args[1]) < 0) {
523        return -errno;
524    }
525    return 0;
526}
527
528int do_setenforce(int nargs, char **args) {
529    if (is_selinux_enabled() <= 0)
530        return 0;
531    if (security_setenforce(atoi(args[1])) < 0) {
532        return -errno;
533    }
534    return 0;
535}
536
537int do_setkey(int nargs, char **args)
538{
539    struct kbentry kbe;
540    kbe.kb_table = strtoul(args[1], 0, 0);
541    kbe.kb_index = strtoul(args[2], 0, 0);
542    kbe.kb_value = strtoul(args[3], 0, 0);
543    return setkey(&kbe);
544}
545
546int do_setprop(int nargs, char **args)
547{
548    const char *name = args[1];
549    const char *value = args[2];
550    char prop_val[PROP_VALUE_MAX];
551    int ret;
552
553    ret = expand_props(prop_val, value, sizeof(prop_val));
554    if (ret) {
555        ERROR("cannot expand '%s' while assigning to '%s'\n", value, name);
556        return -EINVAL;
557    }
558    property_set(name, prop_val);
559    return 0;
560}
561
562int do_setrlimit(int nargs, char **args)
563{
564    struct rlimit limit;
565    int resource;
566    resource = atoi(args[1]);
567    limit.rlim_cur = atoi(args[2]);
568    limit.rlim_max = atoi(args[3]);
569    return setrlimit(resource, &limit);
570}
571
572int do_start(int nargs, char **args)
573{
574    struct service *svc;
575    svc = service_find_by_name(args[1]);
576    if (svc) {
577        service_start(svc, NULL);
578    }
579    return 0;
580}
581
582int do_stop(int nargs, char **args)
583{
584    struct service *svc;
585    svc = service_find_by_name(args[1]);
586    if (svc) {
587        service_stop(svc);
588    }
589    return 0;
590}
591
592int do_restart(int nargs, char **args)
593{
594    struct service *svc;
595    svc = service_find_by_name(args[1]);
596    if (svc) {
597        service_restart(svc);
598    }
599    return 0;
600}
601
602int do_powerctl(int nargs, char **args)
603{
604    char command[PROP_VALUE_MAX];
605    int res;
606    int len = 0;
607    int cmd = 0;
608    char *reboot_target;
609
610    res = expand_props(command, args[1], sizeof(command));
611    if (res) {
612        ERROR("powerctl: cannot expand '%s'\n", args[1]);
613        return -EINVAL;
614    }
615
616    if (strncmp(command, "shutdown", 8) == 0) {
617        cmd = ANDROID_RB_POWEROFF;
618        len = 8;
619    } else if (strncmp(command, "reboot", 6) == 0) {
620        cmd = ANDROID_RB_RESTART2;
621        len = 6;
622    } else {
623        ERROR("powerctl: unrecognized command '%s'\n", command);
624        return -EINVAL;
625    }
626
627    if (command[len] == ',') {
628        reboot_target = &command[len + 1];
629    } else if (command[len] == '\0') {
630        reboot_target = "";
631    } else {
632        ERROR("powerctl: unrecognized reboot target '%s'\n", &command[len]);
633        return -EINVAL;
634    }
635
636    return android_reboot(cmd, 0, reboot_target);
637}
638
639int do_trigger(int nargs, char **args)
640{
641    action_for_each_trigger(args[1], action_add_queue_tail);
642    return 0;
643}
644
645int do_symlink(int nargs, char **args)
646{
647    return symlink(args[1], args[2]);
648}
649
650int do_rm(int nargs, char **args)
651{
652    return unlink(args[1]);
653}
654
655int do_rmdir(int nargs, char **args)
656{
657    return rmdir(args[1]);
658}
659
660int do_sysclktz(int nargs, char **args)
661{
662    struct timezone tz;
663
664    if (nargs != 2)
665        return -1;
666
667    memset(&tz, 0, sizeof(tz));
668    tz.tz_minuteswest = atoi(args[1]);
669    if (settimeofday(NULL, &tz))
670        return -1;
671    return 0;
672}
673
674int do_write(int nargs, char **args)
675{
676    const char *path = args[1];
677    const char *value = args[2];
678    char prop_val[PROP_VALUE_MAX];
679    int ret;
680
681    ret = expand_props(prop_val, value, sizeof(prop_val));
682    if (ret) {
683        ERROR("cannot expand '%s' while writing to '%s'\n", value, path);
684        return -EINVAL;
685    }
686    return write_file(path, prop_val);
687}
688
689int do_copy(int nargs, char **args)
690{
691    char *buffer = NULL;
692    int rc = 0;
693    int fd1 = -1, fd2 = -1;
694    struct stat info;
695    int brtw, brtr;
696    char *p;
697
698    if (nargs != 3)
699        return -1;
700
701    if (stat(args[1], &info) < 0)
702        return -1;
703
704    if ((fd1 = open(args[1], O_RDONLY)) < 0)
705        goto out_err;
706
707    if ((fd2 = open(args[2], O_WRONLY|O_CREAT|O_TRUNC, 0660)) < 0)
708        goto out_err;
709
710    if (!(buffer = malloc(info.st_size)))
711        goto out_err;
712
713    p = buffer;
714    brtr = info.st_size;
715    while(brtr) {
716        rc = read(fd1, p, brtr);
717        if (rc < 0)
718            goto out_err;
719        if (rc == 0)
720            break;
721        p += rc;
722        brtr -= rc;
723    }
724
725    p = buffer;
726    brtw = info.st_size;
727    while(brtw) {
728        rc = write(fd2, p, brtw);
729        if (rc < 0)
730            goto out_err;
731        if (rc == 0)
732            break;
733        p += rc;
734        brtw -= rc;
735    }
736
737    rc = 0;
738    goto out;
739out_err:
740    rc = -1;
741out:
742    if (buffer)
743        free(buffer);
744    if (fd1 >= 0)
745        close(fd1);
746    if (fd2 >= 0)
747        close(fd2);
748    return rc;
749}
750
751int do_chown(int nargs, char **args) {
752    /* GID is optional. */
753    if (nargs == 3) {
754        if (_chown(args[2], decode_uid(args[1]), -1) < 0)
755            return -errno;
756    } else if (nargs == 4) {
757        if (_chown(args[3], decode_uid(args[1]), decode_uid(args[2])) < 0)
758            return -errno;
759    } else {
760        return -1;
761    }
762    return 0;
763}
764
765static mode_t get_mode(const char *s) {
766    mode_t mode = 0;
767    while (*s) {
768        if (*s >= '0' && *s <= '7') {
769            mode = (mode<<3) | (*s-'0');
770        } else {
771            return -1;
772        }
773        s++;
774    }
775    return mode;
776}
777
778int do_chmod(int nargs, char **args) {
779    mode_t mode = get_mode(args[1]);
780    if (_chmod(args[2], mode) < 0) {
781        return -errno;
782    }
783    return 0;
784}
785
786int do_restorecon(int nargs, char **args) {
787    int i;
788
789    for (i = 1; i < nargs; i++) {
790        if (restorecon(args[i]) < 0)
791            return -errno;
792    }
793    return 0;
794}
795
796int do_setsebool(int nargs, char **args) {
797    const char *name = args[1];
798    const char *value = args[2];
799    SELboolean b;
800    int ret;
801
802    if (is_selinux_enabled() <= 0)
803        return 0;
804
805    b.name = name;
806    if (!strcmp(value, "1") || !strcasecmp(value, "true") || !strcasecmp(value, "on"))
807        b.value = 1;
808    else if (!strcmp(value, "0") || !strcasecmp(value, "false") || !strcasecmp(value, "off"))
809        b.value = 0;
810    else {
811        ERROR("setsebool: invalid value %s\n", value);
812        return -EINVAL;
813    }
814
815    if (security_set_boolean_list(1, &b, 0) < 0) {
816        ret = -errno;
817        ERROR("setsebool: could not set %s to %s\n", name, value);
818        return ret;
819    }
820
821    return 0;
822}
823
824int do_loglevel(int nargs, char **args) {
825    if (nargs == 2) {
826        klog_set_level(atoi(args[1]));
827        return 0;
828    }
829    return -1;
830}
831
832int do_load_persist_props(int nargs, char **args) {
833    if (nargs == 1) {
834        load_persist_props();
835        return 0;
836    }
837    return -1;
838}
839
840int do_wait(int nargs, char **args)
841{
842    if (nargs == 2) {
843        return wait_for_file(args[1], COMMAND_RETRY_TIMEOUT);
844    } else if (nargs == 3) {
845        return wait_for_file(args[1], atoi(args[2]));
846    } else
847        return -1;
848}
849