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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 "builtins.h"
18 
19 #include <dirent.h>
20 #include <errno.h>
21 #include <fcntl.h>
22 #include <mntent.h>
23 #include <net/if.h>
24 #include <signal.h>
25 #include <sched.h>
26 #include <stdio.h>
27 #include <stdlib.h>
28 #include <string.h>
29 #include <sys/socket.h>
30 #include <sys/mount.h>
31 #include <sys/resource.h>
32 #include <sys/syscall.h>
33 #include <sys/time.h>
34 #include <sys/types.h>
35 #include <sys/stat.h>
36 #include <sys/wait.h>
37 #include <unistd.h>
38 #include <linux/loop.h>
39 #include <linux/module.h>
40 
41 #include <string>
42 #include <thread>
43 
44 #include <selinux/android.h>
45 #include <selinux/selinux.h>
46 #include <selinux/label.h>
47 
48 #include <android-base/file.h>
49 #include <android-base/parseint.h>
50 #include <android-base/properties.h>
51 #include <android-base/stringprintf.h>
52 #include <android-base/strings.h>
53 #include <bootloader_message/bootloader_message.h>
54 #include <cutils/android_reboot.h>
55 #include <ext4_utils/ext4_crypt.h>
56 #include <ext4_utils/ext4_crypt_init_extensions.h>
57 #include <fs_mgr.h>
58 #include <logwrap/logwrap.h>
59 
60 #include "action.h"
61 #include "bootchart.h"
62 #include "devices.h"
63 #include "init.h"
64 #include "init_parser.h"
65 #include "log.h"
66 #include "property_service.h"
67 #include "reboot.h"
68 #include "service.h"
69 #include "signal_handler.h"
70 #include "util.h"
71 
72 using namespace std::literals::string_literals;
73 
74 #define chmod DO_NOT_USE_CHMOD_USE_FCHMODAT_SYMLINK_NOFOLLOW
75 
76 static constexpr std::chrono::nanoseconds kCommandRetryTimeout = 5s;
77 
insmod(const char * filename,const char * options,int flags)78 static int insmod(const char *filename, const char *options, int flags) {
79     int fd = open(filename, O_RDONLY | O_NOFOLLOW | O_CLOEXEC);
80     if (fd == -1) {
81         PLOG(ERROR) << "insmod: open(\"" << filename << "\") failed";
82         return -1;
83     }
84     int rc = syscall(__NR_finit_module, fd, options, flags);
85     if (rc == -1) {
86         PLOG(ERROR) << "finit_module for \"" << filename << "\" failed";
87     }
88     close(fd);
89     return rc;
90 }
91 
__ifupdown(const char * interface,int up)92 static int __ifupdown(const char *interface, int up) {
93     struct ifreq ifr;
94     int s, ret;
95 
96     strlcpy(ifr.ifr_name, interface, IFNAMSIZ);
97 
98     s = socket(AF_INET, SOCK_DGRAM, 0);
99     if (s < 0)
100         return -1;
101 
102     ret = ioctl(s, SIOCGIFFLAGS, &ifr);
103     if (ret < 0) {
104         goto done;
105     }
106 
107     if (up)
108         ifr.ifr_flags |= IFF_UP;
109     else
110         ifr.ifr_flags &= ~IFF_UP;
111 
112     ret = ioctl(s, SIOCSIFFLAGS, &ifr);
113 
114 done:
115     close(s);
116     return ret;
117 }
118 
reboot_into_recovery(const std::vector<std::string> & options)119 static int reboot_into_recovery(const std::vector<std::string>& options) {
120     std::string err;
121     if (!write_bootloader_message(options, &err)) {
122         LOG(ERROR) << "failed to set bootloader message: " << err;
123         return -1;
124     }
125     DoReboot(ANDROID_RB_RESTART2, "reboot", "recovery", false);
126     return 0;
127 }
128 
do_class_start(const std::vector<std::string> & args)129 static int do_class_start(const std::vector<std::string>& args) {
130         /* Starting a class does not start services
131          * which are explicitly disabled.  They must
132          * be started individually.
133          */
134     ServiceManager::GetInstance().
135         ForEachServiceInClass(args[1], [] (Service* s) { s->StartIfNotDisabled(); });
136     return 0;
137 }
138 
do_class_stop(const std::vector<std::string> & args)139 static int do_class_stop(const std::vector<std::string>& args) {
140     ServiceManager::GetInstance().
141         ForEachServiceInClass(args[1], [] (Service* s) { s->Stop(); });
142     return 0;
143 }
144 
do_class_reset(const std::vector<std::string> & args)145 static int do_class_reset(const std::vector<std::string>& args) {
146     ServiceManager::GetInstance().
147         ForEachServiceInClass(args[1], [] (Service* s) { s->Reset(); });
148     return 0;
149 }
150 
do_class_restart(const std::vector<std::string> & args)151 static int do_class_restart(const std::vector<std::string>& args) {
152     ServiceManager::GetInstance().
153         ForEachServiceInClass(args[1], [] (Service* s) { s->Restart(); });
154     return 0;
155 }
156 
do_domainname(const std::vector<std::string> & args)157 static int do_domainname(const std::vector<std::string>& args) {
158     return write_file("/proc/sys/kernel/domainname", args[1]) ? 0 : 1;
159 }
160 
do_enable(const std::vector<std::string> & args)161 static int do_enable(const std::vector<std::string>& args) {
162     Service* svc = ServiceManager::GetInstance().FindServiceByName(args[1]);
163     if (!svc) {
164         return -1;
165     }
166     return svc->Enable();
167 }
168 
do_exec(const std::vector<std::string> & args)169 static int do_exec(const std::vector<std::string>& args) {
170     return ServiceManager::GetInstance().Exec(args) ? 0 : -1;
171 }
172 
do_exec_start(const std::vector<std::string> & args)173 static int do_exec_start(const std::vector<std::string>& args) {
174     return ServiceManager::GetInstance().ExecStart(args[1]) ? 0 : -1;
175 }
176 
do_export(const std::vector<std::string> & args)177 static int do_export(const std::vector<std::string>& args) {
178     return add_environment(args[1].c_str(), args[2].c_str());
179 }
180 
do_hostname(const std::vector<std::string> & args)181 static int do_hostname(const std::vector<std::string>& args) {
182     return write_file("/proc/sys/kernel/hostname", args[1]) ? 0 : 1;
183 }
184 
do_ifup(const std::vector<std::string> & args)185 static int do_ifup(const std::vector<std::string>& args) {
186     return __ifupdown(args[1].c_str(), 1);
187 }
188 
do_insmod(const std::vector<std::string> & args)189 static int do_insmod(const std::vector<std::string>& args) {
190     int flags = 0;
191     auto it = args.begin() + 1;
192 
193     if (!(*it).compare("-f")) {
194         flags = MODULE_INIT_IGNORE_VERMAGIC | MODULE_INIT_IGNORE_MODVERSIONS;
195         it++;
196     }
197 
198     std::string filename = *it++;
199     std::string options = android::base::Join(std::vector<std::string>(it, args.end()), ' ');
200     return insmod(filename.c_str(), options.c_str(), flags);
201 }
202 
do_mkdir(const std::vector<std::string> & args)203 static int do_mkdir(const std::vector<std::string>& args) {
204     mode_t mode = 0755;
205     int ret;
206 
207     /* mkdir <path> [mode] [owner] [group] */
208 
209     if (args.size() >= 3) {
210         mode = std::strtoul(args[2].c_str(), 0, 8);
211     }
212 
213     ret = make_dir(args[1].c_str(), mode);
214     /* chmod in case the directory already exists */
215     if (ret == -1 && errno == EEXIST) {
216         ret = fchmodat(AT_FDCWD, args[1].c_str(), mode, AT_SYMLINK_NOFOLLOW);
217     }
218     if (ret == -1) {
219         return -errno;
220     }
221 
222     if (args.size() >= 4) {
223         uid_t uid = decode_uid(args[3].c_str());
224         gid_t gid = -1;
225 
226         if (args.size() == 5) {
227             gid = decode_uid(args[4].c_str());
228         }
229 
230         if (lchown(args[1].c_str(), uid, gid) == -1) {
231             return -errno;
232         }
233 
234         /* chown may have cleared S_ISUID and S_ISGID, chmod again */
235         if (mode & (S_ISUID | S_ISGID)) {
236             ret = fchmodat(AT_FDCWD, args[1].c_str(), mode, AT_SYMLINK_NOFOLLOW);
237             if (ret == -1) {
238                 return -errno;
239             }
240         }
241     }
242 
243     if (e4crypt_is_native()) {
244         if (e4crypt_set_directory_policy(args[1].c_str())) {
245             const std::vector<std::string> options = {
246                 "--prompt_and_wipe_data",
247                 "--reason=set_policy_failed:"s + args[1]};
248             reboot_into_recovery(options);
249             return -1;
250         }
251     }
252     return 0;
253 }
254 
255 /* umount <path> */
do_umount(const std::vector<std::string> & args)256 static int do_umount(const std::vector<std::string>& args) {
257   return umount(args[1].c_str());
258 }
259 
260 static struct {
261     const char *name;
262     unsigned flag;
263 } mount_flags[] = {
264     { "noatime",    MS_NOATIME },
265     { "noexec",     MS_NOEXEC },
266     { "nosuid",     MS_NOSUID },
267     { "nodev",      MS_NODEV },
268     { "nodiratime", MS_NODIRATIME },
269     { "ro",         MS_RDONLY },
270     { "rw",         0 },
271     { "remount",    MS_REMOUNT },
272     { "bind",       MS_BIND },
273     { "rec",        MS_REC },
274     { "unbindable", MS_UNBINDABLE },
275     { "private",    MS_PRIVATE },
276     { "slave",      MS_SLAVE },
277     { "shared",     MS_SHARED },
278     { "defaults",   0 },
279     { 0,            0 },
280 };
281 
282 #define DATA_MNT_POINT "/data"
283 
284 /* mount <type> <device> <path> <flags ...> <options> */
do_mount(const std::vector<std::string> & args)285 static int do_mount(const std::vector<std::string>& args) {
286     char tmp[64];
287     const char *source, *target, *system;
288     const char *options = NULL;
289     unsigned flags = 0;
290     std::size_t na = 0;
291     int n, i;
292     int wait = 0;
293 
294     for (na = 4; na < args.size(); na++) {
295         for (i = 0; mount_flags[i].name; i++) {
296             if (!args[na].compare(mount_flags[i].name)) {
297                 flags |= mount_flags[i].flag;
298                 break;
299             }
300         }
301 
302         if (!mount_flags[i].name) {
303             if (!args[na].compare("wait"))
304                 wait = 1;
305             /* if our last argument isn't a flag, wolf it up as an option string */
306             else if (na + 1 == args.size())
307                 options = args[na].c_str();
308         }
309     }
310 
311     system = args[1].c_str();
312     source = args[2].c_str();
313     target = args[3].c_str();
314 
315     if (!strncmp(source, "loop@", 5)) {
316         int mode, loop, fd;
317         struct loop_info info;
318 
319         mode = (flags & MS_RDONLY) ? O_RDONLY : O_RDWR;
320         fd = open(source + 5, mode | O_CLOEXEC);
321         if (fd < 0) {
322             return -1;
323         }
324 
325         for (n = 0; ; n++) {
326             snprintf(tmp, sizeof(tmp), "/dev/block/loop%d", n);
327             loop = open(tmp, mode | O_CLOEXEC);
328             if (loop < 0) {
329                 close(fd);
330                 return -1;
331             }
332 
333             /* if it is a blank loop device */
334             if (ioctl(loop, LOOP_GET_STATUS, &info) < 0 && errno == ENXIO) {
335                 /* if it becomes our loop device */
336                 if (ioctl(loop, LOOP_SET_FD, fd) >= 0) {
337                     close(fd);
338 
339                     if (mount(tmp, target, system, flags, options) < 0) {
340                         ioctl(loop, LOOP_CLR_FD, 0);
341                         close(loop);
342                         return -1;
343                     }
344 
345                     close(loop);
346                     goto exit_success;
347                 }
348             }
349 
350             close(loop);
351         }
352 
353         close(fd);
354         LOG(ERROR) << "out of loopback devices";
355         return -1;
356     } else {
357         if (wait)
358             wait_for_file(source, kCommandRetryTimeout);
359         if (mount(source, target, system, flags, options) < 0) {
360             return -1;
361         }
362 
363     }
364 
365 exit_success:
366     return 0;
367 
368 }
369 
370 /* Imports .rc files from the specified paths. Default ones are applied if none is given.
371  *
372  * start_index: index of the first path in the args list
373  */
import_late(const std::vector<std::string> & args,size_t start_index,size_t end_index)374 static void import_late(const std::vector<std::string>& args, size_t start_index, size_t end_index) {
375     Parser& parser = Parser::GetInstance();
376     if (end_index <= start_index) {
377         // Fallbacks for partitions on which early mount isn't enabled.
378         if (!parser.is_system_etc_init_loaded()) {
379             parser.ParseConfig("/system/etc/init");
380             parser.set_is_system_etc_init_loaded(true);
381         }
382         if (!parser.is_vendor_etc_init_loaded()) {
383             parser.ParseConfig("/vendor/etc/init");
384             parser.set_is_vendor_etc_init_loaded(true);
385         }
386         if (!parser.is_odm_etc_init_loaded()) {
387             parser.ParseConfig("/odm/etc/init");
388             parser.set_is_odm_etc_init_loaded(true);
389         }
390     } else {
391         for (size_t i = start_index; i < end_index; ++i) {
392             parser.ParseConfig(args[i]);
393         }
394     }
395 
396     // Turning this on and letting the INFO logging be discarded adds 0.2s to
397     // Nexus 9 boot time, so it's disabled by default.
398     if (false) parser.DumpState();
399 }
400 
401 /* mount_fstab
402  *
403  *  Call fs_mgr_mount_all() to mount the given fstab
404  */
mount_fstab(const char * fstabfile,int mount_mode)405 static int mount_fstab(const char* fstabfile, int mount_mode) {
406     int ret = -1;
407 
408     /*
409      * Call fs_mgr_mount_all() to mount all filesystems.  We fork(2) and
410      * do the call in the child to provide protection to the main init
411      * process if anything goes wrong (crash or memory leak), and wait for
412      * the child to finish in the parent.
413      */
414     pid_t pid = fork();
415     if (pid > 0) {
416         /* Parent.  Wait for the child to return */
417         int status;
418         int wp_ret = TEMP_FAILURE_RETRY(waitpid(pid, &status, 0));
419         if (wp_ret == -1) {
420             // Unexpected error code. We will continue anyway.
421             PLOG(WARNING) << "waitpid failed";
422         }
423 
424         if (WIFEXITED(status)) {
425             ret = WEXITSTATUS(status);
426         } else {
427             ret = -1;
428         }
429     } else if (pid == 0) {
430         /* child, call fs_mgr_mount_all() */
431 
432         // So we can always see what fs_mgr_mount_all() does.
433         // Only needed if someone explicitly changes the default log level in their init.rc.
434         android::base::ScopedLogSeverity info(android::base::INFO);
435 
436         struct fstab* fstab = fs_mgr_read_fstab(fstabfile);
437         int child_ret = fs_mgr_mount_all(fstab, mount_mode);
438         fs_mgr_free_fstab(fstab);
439         if (child_ret == -1) {
440             PLOG(ERROR) << "fs_mgr_mount_all returned an error";
441         }
442         _exit(child_ret);
443     } else {
444         /* fork failed, return an error */
445         return -1;
446     }
447     return ret;
448 }
449 
450 /* Queue event based on fs_mgr return code.
451  *
452  * code: return code of fs_mgr_mount_all
453  *
454  * This function might request a reboot, in which case it will
455  * not return.
456  *
457  * return code is processed based on input code
458  */
queue_fs_event(int code)459 static int queue_fs_event(int code) {
460     int ret = code;
461     if (code == FS_MGR_MNTALL_DEV_NEEDS_ENCRYPTION) {
462         ActionManager::GetInstance().QueueEventTrigger("encrypt");
463     } else if (code == FS_MGR_MNTALL_DEV_MIGHT_BE_ENCRYPTED) {
464         property_set("ro.crypto.state", "encrypted");
465         property_set("ro.crypto.type", "block");
466         ActionManager::GetInstance().QueueEventTrigger("defaultcrypto");
467     } else if (code == FS_MGR_MNTALL_DEV_NOT_ENCRYPTED) {
468         property_set("ro.crypto.state", "unencrypted");
469         ActionManager::GetInstance().QueueEventTrigger("nonencrypted");
470     } else if (code == FS_MGR_MNTALL_DEV_NOT_ENCRYPTABLE) {
471         property_set("ro.crypto.state", "unsupported");
472         ActionManager::GetInstance().QueueEventTrigger("nonencrypted");
473     } else if (code == FS_MGR_MNTALL_DEV_NEEDS_RECOVERY) {
474         /* Setup a wipe via recovery, and reboot into recovery */
475         PLOG(ERROR) << "fs_mgr_mount_all suggested recovery, so wiping data via recovery.";
476         const std::vector<std::string> options = {"--wipe_data", "--reason=fs_mgr_mount_all" };
477         ret = reboot_into_recovery(options);
478         /* If reboot worked, there is no return. */
479     } else if (code == FS_MGR_MNTALL_DEV_FILE_ENCRYPTED) {
480         if (e4crypt_install_keyring()) {
481             return -1;
482         }
483         property_set("ro.crypto.state", "encrypted");
484         property_set("ro.crypto.type", "file");
485 
486         // Although encrypted, we have device key, so we do not need to
487         // do anything different from the nonencrypted case.
488         ActionManager::GetInstance().QueueEventTrigger("nonencrypted");
489     } else if (code > 0) {
490         PLOG(ERROR) << "fs_mgr_mount_all returned unexpected error " << code;
491     }
492     /* else ... < 0: error */
493 
494     return ret;
495 }
496 
497 /* mount_all <fstab> [ <path> ]* [--<options>]*
498  *
499  * This function might request a reboot, in which case it will
500  * not return.
501  */
do_mount_all(const std::vector<std::string> & args)502 static int do_mount_all(const std::vector<std::string>& args) {
503     std::size_t na = 0;
504     bool import_rc = true;
505     bool queue_event = true;
506     int mount_mode = MOUNT_MODE_DEFAULT;
507     const char* fstabfile = args[1].c_str();
508     std::size_t path_arg_end = args.size();
509     const char* prop_post_fix = "default";
510 
511     for (na = args.size() - 1; na > 1; --na) {
512         if (args[na] == "--early") {
513             path_arg_end = na;
514             queue_event = false;
515             mount_mode = MOUNT_MODE_EARLY;
516             prop_post_fix = "early";
517         } else if (args[na] == "--late") {
518             path_arg_end = na;
519             import_rc = false;
520             mount_mode = MOUNT_MODE_LATE;
521             prop_post_fix = "late";
522         }
523     }
524 
525     std::string prop_name = android::base::StringPrintf("ro.boottime.init.mount_all.%s",
526                                                         prop_post_fix);
527     Timer t;
528     int ret =  mount_fstab(fstabfile, mount_mode);
529     property_set(prop_name.c_str(), std::to_string(t.duration_ms()).c_str());
530 
531     if (import_rc) {
532         /* Paths of .rc files are specified at the 2nd argument and beyond */
533         import_late(args, 2, path_arg_end);
534     }
535 
536     if (queue_event) {
537         /* queue_fs_event will queue event based on mount_fstab return code
538          * and return processed return code*/
539         ret = queue_fs_event(ret);
540     }
541 
542     return ret;
543 }
544 
do_swapon_all(const std::vector<std::string> & args)545 static int do_swapon_all(const std::vector<std::string>& args) {
546     struct fstab *fstab;
547     int ret;
548 
549     fstab = fs_mgr_read_fstab(args[1].c_str());
550     ret = fs_mgr_swapon_all(fstab);
551     fs_mgr_free_fstab(fstab);
552 
553     return ret;
554 }
555 
do_setprop(const std::vector<std::string> & args)556 static int do_setprop(const std::vector<std::string>& args) {
557     const char* name = args[1].c_str();
558     const char* value = args[2].c_str();
559     property_set(name, value);
560     return 0;
561 }
562 
do_setrlimit(const std::vector<std::string> & args)563 static int do_setrlimit(const std::vector<std::string>& args) {
564     struct rlimit limit;
565     int resource;
566     if (android::base::ParseInt(args[1], &resource) &&
567         android::base::ParseUint(args[2], &limit.rlim_cur) &&
568         android::base::ParseUint(args[3], &limit.rlim_max)) {
569         return setrlimit(resource, &limit);
570     }
571     LOG(WARNING) << "ignoring setrlimit " << args[1] << " " << args[2] << " " << args[3];
572     return -1;
573 }
574 
do_start(const std::vector<std::string> & args)575 static int do_start(const std::vector<std::string>& args) {
576     Service* svc = ServiceManager::GetInstance().FindServiceByName(args[1]);
577     if (!svc) {
578         LOG(ERROR) << "do_start: Service " << args[1] << " not found";
579         return -1;
580     }
581     if (!svc->Start())
582         return -1;
583     return 0;
584 }
585 
do_stop(const std::vector<std::string> & args)586 static int do_stop(const std::vector<std::string>& args) {
587     Service* svc = ServiceManager::GetInstance().FindServiceByName(args[1]);
588     if (!svc) {
589         LOG(ERROR) << "do_stop: Service " << args[1] << " not found";
590         return -1;
591     }
592     svc->Stop();
593     return 0;
594 }
595 
do_restart(const std::vector<std::string> & args)596 static int do_restart(const std::vector<std::string>& args) {
597     Service* svc = ServiceManager::GetInstance().FindServiceByName(args[1]);
598     if (!svc) {
599         LOG(ERROR) << "do_restart: Service " << args[1] << " not found";
600         return -1;
601     }
602     svc->Restart();
603     return 0;
604 }
605 
do_trigger(const std::vector<std::string> & args)606 static int do_trigger(const std::vector<std::string>& args) {
607     ActionManager::GetInstance().QueueEventTrigger(args[1]);
608     return 0;
609 }
610 
do_symlink(const std::vector<std::string> & args)611 static int do_symlink(const std::vector<std::string>& args) {
612     return symlink(args[1].c_str(), args[2].c_str());
613 }
614 
do_rm(const std::vector<std::string> & args)615 static int do_rm(const std::vector<std::string>& args) {
616     return unlink(args[1].c_str());
617 }
618 
do_rmdir(const std::vector<std::string> & args)619 static int do_rmdir(const std::vector<std::string>& args) {
620     return rmdir(args[1].c_str());
621 }
622 
do_sysclktz(const std::vector<std::string> & args)623 static int do_sysclktz(const std::vector<std::string>& args) {
624     struct timezone tz = {};
625     if (android::base::ParseInt(args[1], &tz.tz_minuteswest) && settimeofday(NULL, &tz) != -1) {
626         return 0;
627     }
628     return -1;
629 }
630 
do_verity_load_state(const std::vector<std::string> & args)631 static int do_verity_load_state(const std::vector<std::string>& args) {
632     int mode = -1;
633     bool loaded = fs_mgr_load_verity_state(&mode);
634     if (loaded && mode != VERITY_MODE_DEFAULT) {
635         ActionManager::GetInstance().QueueEventTrigger("verity-logging");
636     }
637     return loaded ? 0 : 1;
638 }
639 
verity_update_property(fstab_rec * fstab,const char * mount_point,int mode,int status)640 static void verity_update_property(fstab_rec *fstab, const char *mount_point,
641                                    int mode, int status) {
642     property_set(android::base::StringPrintf("partition.%s.verified", mount_point).c_str(),
643                  android::base::StringPrintf("%d", mode).c_str());
644 }
645 
do_verity_update_state(const std::vector<std::string> & args)646 static int do_verity_update_state(const std::vector<std::string>& args) {
647     return fs_mgr_update_verity_state(verity_update_property) ? 0 : 1;
648 }
649 
do_write(const std::vector<std::string> & args)650 static int do_write(const std::vector<std::string>& args) {
651     return write_file(args[1], args[2]) ? 0 : 1;
652 }
653 
do_copy(const std::vector<std::string> & args)654 static int do_copy(const std::vector<std::string>& args) {
655     std::string data;
656     if (read_file(args[1], &data)) {
657         return write_file(args[2], data) ? 0 : 1;
658     }
659     return 1;
660 }
661 
do_chown(const std::vector<std::string> & args)662 static int do_chown(const std::vector<std::string>& args) {
663     /* GID is optional. */
664     if (args.size() == 3) {
665         if (lchown(args[2].c_str(), decode_uid(args[1].c_str()), -1) == -1)
666             return -errno;
667     } else if (args.size() == 4) {
668         if (lchown(args[3].c_str(), decode_uid(args[1].c_str()),
669                    decode_uid(args[2].c_str())) == -1)
670             return -errno;
671     } else {
672         return -1;
673     }
674     return 0;
675 }
676 
get_mode(const char * s)677 static mode_t get_mode(const char *s) {
678     mode_t mode = 0;
679     while (*s) {
680         if (*s >= '0' && *s <= '7') {
681             mode = (mode<<3) | (*s-'0');
682         } else {
683             return -1;
684         }
685         s++;
686     }
687     return mode;
688 }
689 
do_chmod(const std::vector<std::string> & args)690 static int do_chmod(const std::vector<std::string>& args) {
691     mode_t mode = get_mode(args[1].c_str());
692     if (fchmodat(AT_FDCWD, args[2].c_str(), mode, AT_SYMLINK_NOFOLLOW) < 0) {
693         return -errno;
694     }
695     return 0;
696 }
697 
do_restorecon(const std::vector<std::string> & args)698 static int do_restorecon(const std::vector<std::string>& args) {
699     int ret = 0;
700 
701     struct flag_type {const char* name; int value;};
702     static const flag_type flags[] = {
703         {"--recursive", SELINUX_ANDROID_RESTORECON_RECURSE},
704         {"--skip-ce", SELINUX_ANDROID_RESTORECON_SKIPCE},
705         {"--cross-filesystems", SELINUX_ANDROID_RESTORECON_CROSS_FILESYSTEMS},
706         {0, 0}
707     };
708 
709     int flag = 0;
710 
711     bool in_flags = true;
712     for (size_t i = 1; i < args.size(); ++i) {
713         if (android::base::StartsWith(args[i], "--")) {
714             if (!in_flags) {
715                 LOG(ERROR) << "restorecon - flags must precede paths";
716                 return -1;
717             }
718             bool found = false;
719             for (size_t j = 0; flags[j].name; ++j) {
720                 if (args[i] == flags[j].name) {
721                     flag |= flags[j].value;
722                     found = true;
723                     break;
724                 }
725             }
726             if (!found) {
727                 LOG(ERROR) << "restorecon - bad flag " << args[i];
728                 return -1;
729             }
730         } else {
731             in_flags = false;
732             if (restorecon(args[i].c_str(), flag) < 0) {
733                 ret = -errno;
734             }
735         }
736     }
737     return ret;
738 }
739 
do_restorecon_recursive(const std::vector<std::string> & args)740 static int do_restorecon_recursive(const std::vector<std::string>& args) {
741     std::vector<std::string> non_const_args(args);
742     non_const_args.insert(std::next(non_const_args.begin()), "--recursive");
743     return do_restorecon(non_const_args);
744 }
745 
do_loglevel(const std::vector<std::string> & args)746 static int do_loglevel(const std::vector<std::string>& args) {
747     // TODO: support names instead/as well?
748     int log_level = -1;
749     android::base::ParseInt(args[1], &log_level);
750     android::base::LogSeverity severity;
751     switch (log_level) {
752         case 7: severity = android::base::DEBUG; break;
753         case 6: severity = android::base::INFO; break;
754         case 5:
755         case 4: severity = android::base::WARNING; break;
756         case 3: severity = android::base::ERROR; break;
757         case 2:
758         case 1:
759         case 0: severity = android::base::FATAL; break;
760         default:
761             LOG(ERROR) << "loglevel: invalid log level " << log_level;
762             return -EINVAL;
763     }
764     android::base::SetMinimumLogSeverity(severity);
765     return 0;
766 }
767 
do_load_persist_props(const std::vector<std::string> & args)768 static int do_load_persist_props(const std::vector<std::string>& args) {
769     load_persist_props();
770     return 0;
771 }
772 
do_load_system_props(const std::vector<std::string> & args)773 static int do_load_system_props(const std::vector<std::string>& args) {
774     load_system_props();
775     return 0;
776 }
777 
do_wait(const std::vector<std::string> & args)778 static int do_wait(const std::vector<std::string>& args) {
779     if (args.size() == 2) {
780         return wait_for_file(args[1].c_str(), kCommandRetryTimeout);
781     } else if (args.size() == 3) {
782         int timeout;
783         if (android::base::ParseInt(args[2], &timeout)) {
784             return wait_for_file(args[1].c_str(), std::chrono::seconds(timeout));
785         }
786     }
787     return -1;
788 }
789 
do_wait_for_prop(const std::vector<std::string> & args)790 static int do_wait_for_prop(const std::vector<std::string>& args) {
791     const char* name = args[1].c_str();
792     const char* value = args[2].c_str();
793     size_t value_len = strlen(value);
794 
795     if (!is_legal_property_name(name)) {
796         LOG(ERROR) << "do_wait_for_prop(\"" << name << "\", \"" << value
797                    << "\") failed: bad name";
798         return -1;
799     }
800     if (value_len >= PROP_VALUE_MAX) {
801         LOG(ERROR) << "do_wait_for_prop(\"" << name << "\", \"" << value
802                    << "\") failed: value too long";
803         return -1;
804     }
805     if (!start_waiting_for_property(name, value)) {
806         LOG(ERROR) << "do_wait_for_prop(\"" << name << "\", \"" << value
807                    << "\") failed: init already in waiting";
808         return -1;
809     }
810     return 0;
811 }
812 
813 /*
814  * Callback to make a directory from the ext4 code
815  */
do_installkeys_ensure_dir_exists(const char * dir)816 static int do_installkeys_ensure_dir_exists(const char* dir) {
817     if (make_dir(dir, 0700) && errno != EEXIST) {
818         return -1;
819     }
820 
821     return 0;
822 }
823 
is_file_crypto()824 static bool is_file_crypto() {
825     return android::base::GetProperty("ro.crypto.type", "") == "file";
826 }
827 
do_installkey(const std::vector<std::string> & args)828 static int do_installkey(const std::vector<std::string>& args) {
829     if (!is_file_crypto()) {
830         return 0;
831     }
832     auto unencrypted_dir = args[1] + e4crypt_unencrypted_folder;
833     if (do_installkeys_ensure_dir_exists(unencrypted_dir.c_str())) {
834         PLOG(ERROR) << "Failed to create " << unencrypted_dir;
835         return -1;
836     }
837     std::vector<std::string> exec_args = {"exec", "/system/bin/vdc", "--wait", "cryptfs",
838                                           "enablefilecrypto"};
839     return do_exec(exec_args);
840 }
841 
do_init_user0(const std::vector<std::string> & args)842 static int do_init_user0(const std::vector<std::string>& args) {
843     return e4crypt_do_init_user0();
844 }
845 
map() const846 BuiltinFunctionMap::Map& BuiltinFunctionMap::map() const {
847     constexpr std::size_t kMax = std::numeric_limits<std::size_t>::max();
848     // clang-format off
849     static const Map builtin_functions = {
850         {"bootchart",               {1,     1,    do_bootchart}},
851         {"chmod",                   {2,     2,    do_chmod}},
852         {"chown",                   {2,     3,    do_chown}},
853         {"class_reset",             {1,     1,    do_class_reset}},
854         {"class_restart",           {1,     1,    do_class_restart}},
855         {"class_start",             {1,     1,    do_class_start}},
856         {"class_stop",              {1,     1,    do_class_stop}},
857         {"copy",                    {2,     2,    do_copy}},
858         {"domainname",              {1,     1,    do_domainname}},
859         {"enable",                  {1,     1,    do_enable}},
860         {"exec",                    {1,     kMax, do_exec}},
861         {"exec_start",              {1,     1,    do_exec_start}},
862         {"export",                  {2,     2,    do_export}},
863         {"hostname",                {1,     1,    do_hostname}},
864         {"ifup",                    {1,     1,    do_ifup}},
865         {"init_user0",              {0,     0,    do_init_user0}},
866         {"insmod",                  {1,     kMax, do_insmod}},
867         {"installkey",              {1,     1,    do_installkey}},
868         {"load_persist_props",      {0,     0,    do_load_persist_props}},
869         {"load_system_props",       {0,     0,    do_load_system_props}},
870         {"loglevel",                {1,     1,    do_loglevel}},
871         {"mkdir",                   {1,     4,    do_mkdir}},
872         {"mount_all",               {1,     kMax, do_mount_all}},
873         {"mount",                   {3,     kMax, do_mount}},
874         {"umount",                  {1,     1,    do_umount}},
875         {"restart",                 {1,     1,    do_restart}},
876         {"restorecon",              {1,     kMax, do_restorecon}},
877         {"restorecon_recursive",    {1,     kMax, do_restorecon_recursive}},
878         {"rm",                      {1,     1,    do_rm}},
879         {"rmdir",                   {1,     1,    do_rmdir}},
880         {"setprop",                 {2,     2,    do_setprop}},
881         {"setrlimit",               {3,     3,    do_setrlimit}},
882         {"start",                   {1,     1,    do_start}},
883         {"stop",                    {1,     1,    do_stop}},
884         {"swapon_all",              {1,     1,    do_swapon_all}},
885         {"symlink",                 {2,     2,    do_symlink}},
886         {"sysclktz",                {1,     1,    do_sysclktz}},
887         {"trigger",                 {1,     1,    do_trigger}},
888         {"verity_load_state",       {0,     0,    do_verity_load_state}},
889         {"verity_update_state",     {0,     0,    do_verity_update_state}},
890         {"wait",                    {1,     2,    do_wait}},
891         {"wait_for_prop",           {2,     2,    do_wait_for_prop}},
892         {"write",                   {2,     2,    do_write}},
893     };
894     // clang-format on
895     return builtin_functions;
896 }
897