1/*
2** Copyright 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 <linux/capability.h>
18#include <linux/prctl.h>
19
20#include "installd.h"
21
22
23#define BUFFER_MAX    1024  /* input buffer for commands */
24#define TOKEN_MAX     8     /* max number of arguments in buffer */
25#define REPLY_MAX     256   /* largest reply allowed */
26
27static int do_ping(char **arg, char reply[REPLY_MAX])
28{
29    return 0;
30}
31
32static int do_install(char **arg, char reply[REPLY_MAX])
33{
34    return install(arg[0], atoi(arg[1]), atoi(arg[2])); /* pkgname, uid, gid */
35}
36
37static int do_dexopt(char **arg, char reply[REPLY_MAX])
38{
39        /* apk_path, uid, is_public */
40    return dexopt(arg[0], atoi(arg[1]), atoi(arg[2]));
41}
42
43static int do_move_dex(char **arg, char reply[REPLY_MAX])
44{
45    return move_dex(arg[0], arg[1]); /* src, dst */
46}
47
48static int do_rm_dex(char **arg, char reply[REPLY_MAX])
49{
50    return rm_dex(arg[0]); /* pkgname */
51}
52
53static int do_remove(char **arg, char reply[REPLY_MAX])
54{
55    return uninstall(arg[0], atoi(arg[1])); /* pkgname, userid */
56}
57
58static int do_rename(char **arg, char reply[REPLY_MAX])
59{
60    return renamepkg(arg[0], arg[1]); /* oldpkgname, newpkgname */
61}
62
63static int do_fixuid(char **arg, char reply[REPLY_MAX])
64{
65    return fix_uid(arg[0], atoi(arg[1]), atoi(arg[2])); /* pkgname, uid, gid */
66}
67
68static int do_free_cache(char **arg, char reply[REPLY_MAX]) /* TODO int:free_size */
69{
70    return free_cache((int64_t)atoll(arg[0])); /* free_size */
71}
72
73static int do_rm_cache(char **arg, char reply[REPLY_MAX])
74{
75    return delete_cache(arg[0], atoi(arg[1])); /* pkgname, userid */
76}
77
78static int do_get_size(char **arg, char reply[REPLY_MAX])
79{
80    int64_t codesize = 0;
81    int64_t datasize = 0;
82    int64_t cachesize = 0;
83    int64_t asecsize = 0;
84    int res = 0;
85
86        /* pkgdir, persona, apkpath */
87    res = get_size(arg[0], atoi(arg[1]), arg[2], arg[3], arg[4],
88            &codesize, &datasize, &cachesize, &asecsize);
89
90    /*
91     * Each int64_t can take up 22 characters printed out. Make sure it
92     * doesn't go over REPLY_MAX in the future.
93     */
94    snprintf(reply, REPLY_MAX, "%" PRId64 " %" PRId64 " %" PRId64 " %" PRId64,
95            codesize, datasize, cachesize, asecsize);
96    return res;
97}
98
99static int do_rm_user_data(char **arg, char reply[REPLY_MAX])
100{
101    return delete_user_data(arg[0], atoi(arg[1])); /* pkgname, userid */
102}
103
104static int do_mk_user_data(char **arg, char reply[REPLY_MAX])
105{
106    return make_user_data(arg[0], atoi(arg[1]), atoi(arg[2])); /* pkgname, uid, userid */
107}
108
109static int do_rm_user(char **arg, char reply[REPLY_MAX])
110{
111    return delete_persona(atoi(arg[0])); /* userid */
112}
113
114static int do_clone_user_data(char **arg, char reply[REPLY_MAX])
115{
116    return clone_persona_data(atoi(arg[0]), atoi(arg[1]), atoi(arg[2]));
117}
118
119static int do_movefiles(char **arg, char reply[REPLY_MAX])
120{
121    return movefiles();
122}
123
124static int do_linklib(char **arg, char reply[REPLY_MAX])
125{
126    return linklib(arg[0], arg[1], atoi(arg[2]));
127}
128
129struct cmdinfo {
130    const char *name;
131    unsigned numargs;
132    int (*func)(char **arg, char reply[REPLY_MAX]);
133};
134
135struct cmdinfo cmds[] = {
136    { "ping",                 0, do_ping },
137    { "install",              3, do_install },
138    { "dexopt",               3, do_dexopt },
139    { "movedex",              2, do_move_dex },
140    { "rmdex",                1, do_rm_dex },
141    { "remove",               2, do_remove },
142    { "rename",               2, do_rename },
143    { "fixuid",               3, do_fixuid },
144    { "freecache",            1, do_free_cache },
145    { "rmcache",              2, do_rm_cache },
146    { "getsize",              5, do_get_size },
147    { "rmuserdata",           2, do_rm_user_data },
148    { "movefiles",            0, do_movefiles },
149    { "linklib",              3, do_linklib },
150    { "mkuserdata",           3, do_mk_user_data },
151    { "rmuser",               1, do_rm_user },
152    { "cloneuserdata",        3, do_clone_user_data },
153};
154
155static int readx(int s, void *_buf, int count)
156{
157    char *buf = _buf;
158    int n = 0, r;
159    if (count < 0) return -1;
160    while (n < count) {
161        r = read(s, buf + n, count - n);
162        if (r < 0) {
163            if (errno == EINTR) continue;
164            ALOGE("read error: %s\n", strerror(errno));
165            return -1;
166        }
167        if (r == 0) {
168            ALOGE("eof\n");
169            return -1; /* EOF */
170        }
171        n += r;
172    }
173    return 0;
174}
175
176static int writex(int s, const void *_buf, int count)
177{
178    const char *buf = _buf;
179    int n = 0, r;
180    if (count < 0) return -1;
181    while (n < count) {
182        r = write(s, buf + n, count - n);
183        if (r < 0) {
184            if (errno == EINTR) continue;
185            ALOGE("write error: %s\n", strerror(errno));
186            return -1;
187        }
188        n += r;
189    }
190    return 0;
191}
192
193
194/* Tokenize the command buffer, locate a matching command,
195 * ensure that the required number of arguments are provided,
196 * call the function(), return the result.
197 */
198static int execute(int s, char cmd[BUFFER_MAX])
199{
200    char reply[REPLY_MAX];
201    char *arg[TOKEN_MAX+1];
202    unsigned i;
203    unsigned n = 0;
204    unsigned short count;
205    int ret = -1;
206
207//    ALOGI("execute('%s')\n", cmd);
208
209        /* default reply is "" */
210    reply[0] = 0;
211
212        /* n is number of args (not counting arg[0]) */
213    arg[0] = cmd;
214    while (*cmd) {
215        if (isspace(*cmd)) {
216            *cmd++ = 0;
217            n++;
218            arg[n] = cmd;
219            if (n == TOKEN_MAX) {
220                ALOGE("too many arguments\n");
221                goto done;
222            }
223        }
224        cmd++;
225    }
226
227    for (i = 0; i < sizeof(cmds) / sizeof(cmds[0]); i++) {
228        if (!strcmp(cmds[i].name,arg[0])) {
229            if (n != cmds[i].numargs) {
230                ALOGE("%s requires %d arguments (%d given)\n",
231                     cmds[i].name, cmds[i].numargs, n);
232            } else {
233                ret = cmds[i].func(arg + 1, reply);
234            }
235            goto done;
236        }
237    }
238    ALOGE("unsupported command '%s'\n", arg[0]);
239
240done:
241    if (reply[0]) {
242        n = snprintf(cmd, BUFFER_MAX, "%d %s", ret, reply);
243    } else {
244        n = snprintf(cmd, BUFFER_MAX, "%d", ret);
245    }
246    if (n > BUFFER_MAX) n = BUFFER_MAX;
247    count = n;
248
249//    ALOGI("reply: '%s'\n", cmd);
250    if (writex(s, &count, sizeof(count))) return -1;
251    if (writex(s, cmd, count)) return -1;
252    return 0;
253}
254
255/**
256 * Initialize all the global variables that are used elsewhere. Returns 0 upon
257 * success and -1 on error.
258 */
259void free_globals() {
260    size_t i;
261
262    for (i = 0; i < android_system_dirs.count; i++) {
263        if (android_system_dirs.dirs[i].path != NULL) {
264            free(android_system_dirs.dirs[i].path);
265        }
266    }
267
268    free(android_system_dirs.dirs);
269}
270
271int initialize_globals() {
272    // Get the android data directory.
273    if (get_path_from_env(&android_data_dir, "ANDROID_DATA") < 0) {
274        return -1;
275    }
276
277    // Get the android app directory.
278    if (copy_and_append(&android_app_dir, &android_data_dir, APP_SUBDIR) < 0) {
279        return -1;
280    }
281
282    // Get the android protected app directory.
283    if (copy_and_append(&android_app_private_dir, &android_data_dir, PRIVATE_APP_SUBDIR) < 0) {
284        return -1;
285    }
286
287    // Get the android app native library directory.
288    if (copy_and_append(&android_app_lib_dir, &android_data_dir, APP_LIB_SUBDIR) < 0) {
289        return -1;
290    }
291
292    // Get the sd-card ASEC mount point.
293    if (get_path_from_env(&android_asec_dir, "ASEC_MOUNTPOINT") < 0) {
294        return -1;
295    }
296
297    // Get the android media directory.
298    if (copy_and_append(&android_media_dir, &android_data_dir, MEDIA_SUBDIR) < 0) {
299        return -1;
300    }
301
302    // Take note of the system and vendor directories.
303    android_system_dirs.count = 2;
304
305    android_system_dirs.dirs = calloc(android_system_dirs.count, sizeof(dir_rec_t));
306    if (android_system_dirs.dirs == NULL) {
307        ALOGE("Couldn't allocate array for dirs; aborting\n");
308        return -1;
309    }
310
311    // system
312    if (get_path_from_env(&android_system_dirs.dirs[0], "ANDROID_ROOT") < 0) {
313        free_globals();
314        return -1;
315    }
316
317    // append "app/" to dirs[0]
318    char *system_app_path = build_string2(android_system_dirs.dirs[0].path, APP_SUBDIR);
319    android_system_dirs.dirs[0].path = system_app_path;
320    android_system_dirs.dirs[0].len = strlen(system_app_path);
321
322    // vendor
323    // TODO replace this with an environment variable (doesn't exist yet)
324    android_system_dirs.dirs[1].path = "/vendor/app/";
325    android_system_dirs.dirs[1].len = strlen(android_system_dirs.dirs[1].path);
326
327    return 0;
328}
329
330int initialize_directories() {
331    int res = -1;
332
333    // Read current filesystem layout version to handle upgrade paths
334    char version_path[PATH_MAX];
335    snprintf(version_path, PATH_MAX, "%s.layout_version", android_data_dir.path);
336
337    int oldVersion;
338    if (fs_read_atomic_int(version_path, &oldVersion) == -1) {
339        oldVersion = 0;
340    }
341    int version = oldVersion;
342
343    // /data/user
344    char *user_data_dir = build_string2(android_data_dir.path, SECONDARY_USER_PREFIX);
345    // /data/data
346    char *legacy_data_dir = build_string2(android_data_dir.path, PRIMARY_USER_PREFIX);
347    // /data/user/0
348    char *primary_data_dir = build_string3(android_data_dir.path, SECONDARY_USER_PREFIX, "0");
349    if (!user_data_dir || !legacy_data_dir || !primary_data_dir) {
350        goto fail;
351    }
352
353    // Make the /data/user directory if necessary
354    if (access(user_data_dir, R_OK) < 0) {
355        if (mkdir(user_data_dir, 0711) < 0) {
356            goto fail;
357        }
358        if (chown(user_data_dir, AID_SYSTEM, AID_SYSTEM) < 0) {
359            goto fail;
360        }
361        if (chmod(user_data_dir, 0711) < 0) {
362            goto fail;
363        }
364    }
365    // Make the /data/user/0 symlink to /data/data if necessary
366    if (access(primary_data_dir, R_OK) < 0) {
367        if (symlink(legacy_data_dir, primary_data_dir)) {
368            goto fail;
369        }
370    }
371
372    if (version == 0) {
373        // Introducing multi-user, so migrate /data/media contents into /data/media/0
374        ALOGD("Upgrading /data/media for multi-user");
375
376        // Ensure /data/media
377        if (fs_prepare_dir(android_media_dir.path, 0770, AID_MEDIA_RW, AID_MEDIA_RW) == -1) {
378            goto fail;
379        }
380
381        // /data/media.tmp
382        char media_tmp_dir[PATH_MAX];
383        snprintf(media_tmp_dir, PATH_MAX, "%smedia.tmp", android_data_dir.path);
384
385        // Only copy when upgrade not already in progress
386        if (access(media_tmp_dir, F_OK) == -1) {
387            if (rename(android_media_dir.path, media_tmp_dir) == -1) {
388                ALOGE("Failed to move legacy media path: %s", strerror(errno));
389                goto fail;
390            }
391        }
392
393        // Create /data/media again
394        if (fs_prepare_dir(android_media_dir.path, 0770, AID_MEDIA_RW, AID_MEDIA_RW) == -1) {
395            goto fail;
396        }
397
398        // /data/media/0
399        char owner_media_dir[PATH_MAX];
400        snprintf(owner_media_dir, PATH_MAX, "%s0", android_media_dir.path);
401
402        // Move any owner data into place
403        if (access(media_tmp_dir, F_OK) == 0) {
404            if (rename(media_tmp_dir, owner_media_dir) == -1) {
405                ALOGE("Failed to move owner media path: %s", strerror(errno));
406                goto fail;
407            }
408        }
409
410        // Ensure media directories for any existing users
411        DIR *dir;
412        struct dirent *dirent;
413        char user_media_dir[PATH_MAX];
414
415        dir = opendir(user_data_dir);
416        if (dir != NULL) {
417            while ((dirent = readdir(dir))) {
418                if (dirent->d_type == DT_DIR) {
419                    const char *name = dirent->d_name;
420
421                    // skip "." and ".."
422                    if (name[0] == '.') {
423                        if (name[1] == 0) continue;
424                        if ((name[1] == '.') && (name[2] == 0)) continue;
425                    }
426
427                    // /data/media/<user_id>
428                    snprintf(user_media_dir, PATH_MAX, "%s%s", android_media_dir.path, name);
429                    if (fs_prepare_dir(user_media_dir, 0770, AID_MEDIA_RW, AID_MEDIA_RW) == -1) {
430                        goto fail;
431                    }
432                }
433            }
434            closedir(dir);
435        }
436
437        version = 1;
438    }
439
440    // /data/media/obb
441    char media_obb_dir[PATH_MAX];
442    snprintf(media_obb_dir, PATH_MAX, "%sobb", android_media_dir.path);
443
444    if (version == 1) {
445        // Introducing /data/media/obb for sharing OBB across users; migrate
446        // any existing OBB files from owner.
447        ALOGD("Upgrading to shared /data/media/obb");
448
449        // /data/media/0/Android/obb
450        char owner_obb_path[PATH_MAX];
451        snprintf(owner_obb_path, PATH_MAX, "%s0/Android/obb", android_media_dir.path);
452
453        // Only move if target doesn't already exist
454        if (access(media_obb_dir, F_OK) != 0 && access(owner_obb_path, F_OK) == 0) {
455            if (rename(owner_obb_path, media_obb_dir) == -1) {
456                ALOGE("Failed to move OBB from owner: %s", strerror(errno));
457                goto fail;
458            }
459        }
460
461        version = 2;
462    }
463
464    if (ensure_media_user_dirs(0) == -1) {
465        ALOGE("Failed to setup media for user 0");
466        goto fail;
467    }
468    if (fs_prepare_dir(media_obb_dir, 0770, AID_MEDIA_RW, AID_MEDIA_RW) == -1) {
469        goto fail;
470    }
471
472    // Persist layout version if changed
473    if (version != oldVersion) {
474        if (fs_write_atomic_int(version_path, version) == -1) {
475            ALOGE("Failed to save version to %s: %s", version_path, strerror(errno));
476            goto fail;
477        }
478    }
479
480    // Success!
481    res = 0;
482
483fail:
484    free(user_data_dir);
485    free(legacy_data_dir);
486    free(primary_data_dir);
487    return res;
488}
489
490static void drop_privileges() {
491    if (prctl(PR_SET_KEEPCAPS, 1) < 0) {
492        ALOGE("prctl(PR_SET_KEEPCAPS) failed: %s\n", strerror(errno));
493        exit(1);
494    }
495
496    if (setgid(AID_INSTALL) < 0) {
497        ALOGE("setgid() can't drop privileges; exiting.\n");
498        exit(1);
499    }
500
501    if (setuid(AID_INSTALL) < 0) {
502        ALOGE("setuid() can't drop privileges; exiting.\n");
503        exit(1);
504    }
505
506    struct __user_cap_header_struct capheader;
507    struct __user_cap_data_struct capdata[2];
508    memset(&capheader, 0, sizeof(capheader));
509    memset(&capdata, 0, sizeof(capdata));
510    capheader.version = _LINUX_CAPABILITY_VERSION_3;
511    capheader.pid = 0;
512
513    capdata[CAP_TO_INDEX(CAP_DAC_OVERRIDE)].permitted |= CAP_TO_MASK(CAP_DAC_OVERRIDE);
514    capdata[CAP_TO_INDEX(CAP_CHOWN)].permitted        |= CAP_TO_MASK(CAP_CHOWN);
515    capdata[CAP_TO_INDEX(CAP_SETUID)].permitted       |= CAP_TO_MASK(CAP_SETUID);
516    capdata[CAP_TO_INDEX(CAP_SETGID)].permitted       |= CAP_TO_MASK(CAP_SETGID);
517
518    capdata[0].effective = capdata[0].permitted;
519    capdata[1].effective = capdata[1].permitted;
520    capdata[0].inheritable = 0;
521    capdata[1].inheritable = 0;
522
523    if (capset(&capheader, &capdata[0]) < 0) {
524        ALOGE("capset failed: %s\n", strerror(errno));
525        exit(1);
526    }
527}
528
529int main(const int argc, const char *argv[]) {
530    char buf[BUFFER_MAX];
531    struct sockaddr addr;
532    socklen_t alen;
533    int lsocket, s, count;
534
535    ALOGI("installd firing up\n");
536
537    if (initialize_globals() < 0) {
538        ALOGE("Could not initialize globals; exiting.\n");
539        exit(1);
540    }
541
542    if (initialize_directories() < 0) {
543        ALOGE("Could not create directories; exiting.\n");
544        exit(1);
545    }
546
547    drop_privileges();
548
549    lsocket = android_get_control_socket(SOCKET_PATH);
550    if (lsocket < 0) {
551        ALOGE("Failed to get socket from environment: %s\n", strerror(errno));
552        exit(1);
553    }
554    if (listen(lsocket, 5)) {
555        ALOGE("Listen on socket failed: %s\n", strerror(errno));
556        exit(1);
557    }
558    fcntl(lsocket, F_SETFD, FD_CLOEXEC);
559
560    for (;;) {
561        alen = sizeof(addr);
562        s = accept(lsocket, &addr, &alen);
563        if (s < 0) {
564            ALOGE("Accept failed: %s\n", strerror(errno));
565            continue;
566        }
567        fcntl(s, F_SETFD, FD_CLOEXEC);
568
569        ALOGI("new connection\n");
570        for (;;) {
571            unsigned short count;
572            if (readx(s, &count, sizeof(count))) {
573                ALOGE("failed to read size\n");
574                break;
575            }
576            if ((count < 1) || (count >= BUFFER_MAX)) {
577                ALOGE("invalid size %d\n", count);
578                break;
579            }
580            if (readx(s, buf, count)) {
581                ALOGE("failed to read command\n");
582                break;
583            }
584            buf[count] = 0;
585            if (execute(s, buf)) break;
586        }
587        ALOGI("closing connection\n");
588        close(s);
589    }
590
591    return 0;
592}
593