/* ** Copyright 2008, The Android Open Source Project ** ** Licensed under the Apache License, Version 2.0 (the "License"); ** you may not use this file except in compliance with the License. ** You may obtain a copy of the License at ** ** http://www.apache.org/licenses/LICENSE-2.0 ** ** Unless required by applicable law or agreed to in writing, software ** distributed under the License is distributed on an "AS IS" BASIS, ** WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. ** See the License for the specific language governing permissions and ** limitations under the License. */ #include <linux/capability.h> #include <linux/prctl.h> #include "installd.h" #define BUFFER_MAX 1024 /* input buffer for commands */ #define TOKEN_MAX 8 /* max number of arguments in buffer */ #define REPLY_MAX 256 /* largest reply allowed */ static int do_ping(char **arg, char reply[REPLY_MAX]) { return 0; } static int do_install(char **arg, char reply[REPLY_MAX]) { return install(arg[0], atoi(arg[1]), atoi(arg[2])); /* pkgname, uid, gid */ } static int do_dexopt(char **arg, char reply[REPLY_MAX]) { /* apk_path, uid, is_public */ return dexopt(arg[0], atoi(arg[1]), atoi(arg[2])); } static int do_move_dex(char **arg, char reply[REPLY_MAX]) { return move_dex(arg[0], arg[1]); /* src, dst */ } static int do_rm_dex(char **arg, char reply[REPLY_MAX]) { return rm_dex(arg[0]); /* pkgname */ } static int do_remove(char **arg, char reply[REPLY_MAX]) { return uninstall(arg[0], atoi(arg[1])); /* pkgname, userid */ } static int do_rename(char **arg, char reply[REPLY_MAX]) { return renamepkg(arg[0], arg[1]); /* oldpkgname, newpkgname */ } static int do_fixuid(char **arg, char reply[REPLY_MAX]) { return fix_uid(arg[0], atoi(arg[1]), atoi(arg[2])); /* pkgname, uid, gid */ } static int do_free_cache(char **arg, char reply[REPLY_MAX]) /* TODO int:free_size */ { return free_cache((int64_t)atoll(arg[0])); /* free_size */ } static int do_rm_cache(char **arg, char reply[REPLY_MAX]) { return delete_cache(arg[0], atoi(arg[1])); /* pkgname, userid */ } static int do_get_size(char **arg, char reply[REPLY_MAX]) { int64_t codesize = 0; int64_t datasize = 0; int64_t cachesize = 0; int64_t asecsize = 0; int res = 0; /* pkgdir, persona, apkpath */ res = get_size(arg[0], atoi(arg[1]), arg[2], arg[3], arg[4], &codesize, &datasize, &cachesize, &asecsize); /* * Each int64_t can take up 22 characters printed out. Make sure it * doesn't go over REPLY_MAX in the future. */ snprintf(reply, REPLY_MAX, "%" PRId64 " %" PRId64 " %" PRId64 " %" PRId64, codesize, datasize, cachesize, asecsize); return res; } static int do_rm_user_data(char **arg, char reply[REPLY_MAX]) { return delete_user_data(arg[0], atoi(arg[1])); /* pkgname, userid */ } static int do_mk_user_data(char **arg, char reply[REPLY_MAX]) { return make_user_data(arg[0], atoi(arg[1]), atoi(arg[2])); /* pkgname, uid, userid */ } static int do_rm_user(char **arg, char reply[REPLY_MAX]) { return delete_persona(atoi(arg[0])); /* userid */ } static int do_clone_user_data(char **arg, char reply[REPLY_MAX]) { return clone_persona_data(atoi(arg[0]), atoi(arg[1]), atoi(arg[2])); } static int do_movefiles(char **arg, char reply[REPLY_MAX]) { return movefiles(); } static int do_linklib(char **arg, char reply[REPLY_MAX]) { return linklib(arg[0], arg[1], atoi(arg[2])); } struct cmdinfo { const char *name; unsigned numargs; int (*func)(char **arg, char reply[REPLY_MAX]); }; struct cmdinfo cmds[] = { { "ping", 0, do_ping }, { "install", 3, do_install }, { "dexopt", 3, do_dexopt }, { "movedex", 2, do_move_dex }, { "rmdex", 1, do_rm_dex }, { "remove", 2, do_remove }, { "rename", 2, do_rename }, { "fixuid", 3, do_fixuid }, { "freecache", 1, do_free_cache }, { "rmcache", 2, do_rm_cache }, { "getsize", 5, do_get_size }, { "rmuserdata", 2, do_rm_user_data }, { "movefiles", 0, do_movefiles }, { "linklib", 3, do_linklib }, { "mkuserdata", 3, do_mk_user_data }, { "rmuser", 1, do_rm_user }, { "cloneuserdata", 3, do_clone_user_data }, }; static int readx(int s, void *_buf, int count) { char *buf = _buf; int n = 0, r; if (count < 0) return -1; while (n < count) { r = read(s, buf + n, count - n); if (r < 0) { if (errno == EINTR) continue; ALOGE("read error: %s\n", strerror(errno)); return -1; } if (r == 0) { ALOGE("eof\n"); return -1; /* EOF */ } n += r; } return 0; } static int writex(int s, const void *_buf, int count) { const char *buf = _buf; int n = 0, r; if (count < 0) return -1; while (n < count) { r = write(s, buf + n, count - n); if (r < 0) { if (errno == EINTR) continue; ALOGE("write error: %s\n", strerror(errno)); return -1; } n += r; } return 0; } /* Tokenize the command buffer, locate a matching command, * ensure that the required number of arguments are provided, * call the function(), return the result. */ static int execute(int s, char cmd[BUFFER_MAX]) { char reply[REPLY_MAX]; char *arg[TOKEN_MAX+1]; unsigned i; unsigned n = 0; unsigned short count; int ret = -1; // ALOGI("execute('%s')\n", cmd); /* default reply is "" */ reply[0] = 0; /* n is number of args (not counting arg[0]) */ arg[0] = cmd; while (*cmd) { if (isspace(*cmd)) { *cmd++ = 0; n++; arg[n] = cmd; if (n == TOKEN_MAX) { ALOGE("too many arguments\n"); goto done; } } cmd++; } for (i = 0; i < sizeof(cmds) / sizeof(cmds[0]); i++) { if (!strcmp(cmds[i].name,arg[0])) { if (n != cmds[i].numargs) { ALOGE("%s requires %d arguments (%d given)\n", cmds[i].name, cmds[i].numargs, n); } else { ret = cmds[i].func(arg + 1, reply); } goto done; } } ALOGE("unsupported command '%s'\n", arg[0]); done: if (reply[0]) { n = snprintf(cmd, BUFFER_MAX, "%d %s", ret, reply); } else { n = snprintf(cmd, BUFFER_MAX, "%d", ret); } if (n > BUFFER_MAX) n = BUFFER_MAX; count = n; // ALOGI("reply: '%s'\n", cmd); if (writex(s, &count, sizeof(count))) return -1; if (writex(s, cmd, count)) return -1; return 0; } /** * Initialize all the global variables that are used elsewhere. Returns 0 upon * success and -1 on error. */ void free_globals() { size_t i; for (i = 0; i < android_system_dirs.count; i++) { if (android_system_dirs.dirs[i].path != NULL) { free(android_system_dirs.dirs[i].path); } } free(android_system_dirs.dirs); } int initialize_globals() { // Get the android data directory. if (get_path_from_env(&android_data_dir, "ANDROID_DATA") < 0) { return -1; } // Get the android app directory. if (copy_and_append(&android_app_dir, &android_data_dir, APP_SUBDIR) < 0) { return -1; } // Get the android protected app directory. if (copy_and_append(&android_app_private_dir, &android_data_dir, PRIVATE_APP_SUBDIR) < 0) { return -1; } // Get the android app native library directory. if (copy_and_append(&android_app_lib_dir, &android_data_dir, APP_LIB_SUBDIR) < 0) { return -1; } // Get the sd-card ASEC mount point. if (get_path_from_env(&android_asec_dir, "ASEC_MOUNTPOINT") < 0) { return -1; } // Get the android media directory. if (copy_and_append(&android_media_dir, &android_data_dir, MEDIA_SUBDIR) < 0) { return -1; } // Take note of the system and vendor directories. android_system_dirs.count = 2; android_system_dirs.dirs = calloc(android_system_dirs.count, sizeof(dir_rec_t)); if (android_system_dirs.dirs == NULL) { ALOGE("Couldn't allocate array for dirs; aborting\n"); return -1; } // system if (get_path_from_env(&android_system_dirs.dirs[0], "ANDROID_ROOT") < 0) { free_globals(); return -1; } // append "app/" to dirs[0] char *system_app_path = build_string2(android_system_dirs.dirs[0].path, APP_SUBDIR); android_system_dirs.dirs[0].path = system_app_path; android_system_dirs.dirs[0].len = strlen(system_app_path); // vendor // TODO replace this with an environment variable (doesn't exist yet) android_system_dirs.dirs[1].path = "/vendor/app/"; android_system_dirs.dirs[1].len = strlen(android_system_dirs.dirs[1].path); return 0; } int initialize_directories() { int res = -1; // Read current filesystem layout version to handle upgrade paths char version_path[PATH_MAX]; snprintf(version_path, PATH_MAX, "%s.layout_version", android_data_dir.path); int oldVersion; if (fs_read_atomic_int(version_path, &oldVersion) == -1) { oldVersion = 0; } int version = oldVersion; // /data/user char *user_data_dir = build_string2(android_data_dir.path, SECONDARY_USER_PREFIX); // /data/data char *legacy_data_dir = build_string2(android_data_dir.path, PRIMARY_USER_PREFIX); // /data/user/0 char *primary_data_dir = build_string3(android_data_dir.path, SECONDARY_USER_PREFIX, "0"); if (!user_data_dir || !legacy_data_dir || !primary_data_dir) { goto fail; } // Make the /data/user directory if necessary if (access(user_data_dir, R_OK) < 0) { if (mkdir(user_data_dir, 0711) < 0) { goto fail; } if (chown(user_data_dir, AID_SYSTEM, AID_SYSTEM) < 0) { goto fail; } if (chmod(user_data_dir, 0711) < 0) { goto fail; } } // Make the /data/user/0 symlink to /data/data if necessary if (access(primary_data_dir, R_OK) < 0) { if (symlink(legacy_data_dir, primary_data_dir)) { goto fail; } } if (version == 0) { // Introducing multi-user, so migrate /data/media contents into /data/media/0 ALOGD("Upgrading /data/media for multi-user"); // Ensure /data/media if (fs_prepare_dir(android_media_dir.path, 0770, AID_MEDIA_RW, AID_MEDIA_RW) == -1) { goto fail; } // /data/media.tmp char media_tmp_dir[PATH_MAX]; snprintf(media_tmp_dir, PATH_MAX, "%smedia.tmp", android_data_dir.path); // Only copy when upgrade not already in progress if (access(media_tmp_dir, F_OK) == -1) { if (rename(android_media_dir.path, media_tmp_dir) == -1) { ALOGE("Failed to move legacy media path: %s", strerror(errno)); goto fail; } } // Create /data/media again if (fs_prepare_dir(android_media_dir.path, 0770, AID_MEDIA_RW, AID_MEDIA_RW) == -1) { goto fail; } // /data/media/0 char owner_media_dir[PATH_MAX]; snprintf(owner_media_dir, PATH_MAX, "%s0", android_media_dir.path); // Move any owner data into place if (access(media_tmp_dir, F_OK) == 0) { if (rename(media_tmp_dir, owner_media_dir) == -1) { ALOGE("Failed to move owner media path: %s", strerror(errno)); goto fail; } } // Ensure media directories for any existing users DIR *dir; struct dirent *dirent; char user_media_dir[PATH_MAX]; dir = opendir(user_data_dir); if (dir != NULL) { while ((dirent = readdir(dir))) { if (dirent->d_type == DT_DIR) { const char *name = dirent->d_name; // skip "." and ".." if (name[0] == '.') { if (name[1] == 0) continue; if ((name[1] == '.') && (name[2] == 0)) continue; } // /data/media/<user_id> snprintf(user_media_dir, PATH_MAX, "%s%s", android_media_dir.path, name); if (fs_prepare_dir(user_media_dir, 0770, AID_MEDIA_RW, AID_MEDIA_RW) == -1) { goto fail; } } } closedir(dir); } version = 1; } // /data/media/obb char media_obb_dir[PATH_MAX]; snprintf(media_obb_dir, PATH_MAX, "%sobb", android_media_dir.path); if (version == 1) { // Introducing /data/media/obb for sharing OBB across users; migrate // any existing OBB files from owner. ALOGD("Upgrading to shared /data/media/obb"); // /data/media/0/Android/obb char owner_obb_path[PATH_MAX]; snprintf(owner_obb_path, PATH_MAX, "%s0/Android/obb", android_media_dir.path); // Only move if target doesn't already exist if (access(media_obb_dir, F_OK) != 0 && access(owner_obb_path, F_OK) == 0) { if (rename(owner_obb_path, media_obb_dir) == -1) { ALOGE("Failed to move OBB from owner: %s", strerror(errno)); goto fail; } } version = 2; } if (ensure_media_user_dirs(0) == -1) { ALOGE("Failed to setup media for user 0"); goto fail; } if (fs_prepare_dir(media_obb_dir, 0770, AID_MEDIA_RW, AID_MEDIA_RW) == -1) { goto fail; } // Persist layout version if changed if (version != oldVersion) { if (fs_write_atomic_int(version_path, version) == -1) { ALOGE("Failed to save version to %s: %s", version_path, strerror(errno)); goto fail; } } // Success! res = 0; fail: free(user_data_dir); free(legacy_data_dir); free(primary_data_dir); return res; } static void drop_privileges() { if (prctl(PR_SET_KEEPCAPS, 1) < 0) { ALOGE("prctl(PR_SET_KEEPCAPS) failed: %s\n", strerror(errno)); exit(1); } if (setgid(AID_INSTALL) < 0) { ALOGE("setgid() can't drop privileges; exiting.\n"); exit(1); } if (setuid(AID_INSTALL) < 0) { ALOGE("setuid() can't drop privileges; exiting.\n"); exit(1); } struct __user_cap_header_struct capheader; struct __user_cap_data_struct capdata[2]; memset(&capheader, 0, sizeof(capheader)); memset(&capdata, 0, sizeof(capdata)); capheader.version = _LINUX_CAPABILITY_VERSION_3; capheader.pid = 0; capdata[CAP_TO_INDEX(CAP_DAC_OVERRIDE)].permitted |= CAP_TO_MASK(CAP_DAC_OVERRIDE); capdata[CAP_TO_INDEX(CAP_CHOWN)].permitted |= CAP_TO_MASK(CAP_CHOWN); capdata[CAP_TO_INDEX(CAP_SETUID)].permitted |= CAP_TO_MASK(CAP_SETUID); capdata[CAP_TO_INDEX(CAP_SETGID)].permitted |= CAP_TO_MASK(CAP_SETGID); capdata[0].effective = capdata[0].permitted; capdata[1].effective = capdata[1].permitted; capdata[0].inheritable = 0; capdata[1].inheritable = 0; if (capset(&capheader, &capdata[0]) < 0) { ALOGE("capset failed: %s\n", strerror(errno)); exit(1); } } int main(const int argc, const char *argv[]) { char buf[BUFFER_MAX]; struct sockaddr addr; socklen_t alen; int lsocket, s, count; ALOGI("installd firing up\n"); if (initialize_globals() < 0) { ALOGE("Could not initialize globals; exiting.\n"); exit(1); } if (initialize_directories() < 0) { ALOGE("Could not create directories; exiting.\n"); exit(1); } drop_privileges(); lsocket = android_get_control_socket(SOCKET_PATH); if (lsocket < 0) { ALOGE("Failed to get socket from environment: %s\n", strerror(errno)); exit(1); } if (listen(lsocket, 5)) { ALOGE("Listen on socket failed: %s\n", strerror(errno)); exit(1); } fcntl(lsocket, F_SETFD, FD_CLOEXEC); for (;;) { alen = sizeof(addr); s = accept(lsocket, &addr, &alen); if (s < 0) { ALOGE("Accept failed: %s\n", strerror(errno)); continue; } fcntl(s, F_SETFD, FD_CLOEXEC); ALOGI("new connection\n"); for (;;) { unsigned short count; if (readx(s, &count, sizeof(count))) { ALOGE("failed to read size\n"); break; } if ((count < 1) || (count >= BUFFER_MAX)) { ALOGE("invalid size %d\n", count); break; } if (readx(s, buf, count)) { ALOGE("failed to read command\n"); break; } buf[count] = 0; if (execute(s, buf)) break; } ALOGI("closing connection\n"); close(s); } return 0; }