/* * Copyright (C) 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 <stdio.h>#include <stdlib.h>#include <string.h>#include <unistd.h>#include <fcntl.h>#include <ctype.h>#include <signal.h>#include <sys/wait.h>#include <sys/mount.h>#include <sys/stat.h>#include <sys/poll.h>#include <errno.h>#include <stdarg.h>#include <mtd/mtd-user.h>#include <sys/types.h>#include <sys/socket.h>#include <sys/un.h>#include <selinux/selinux.h>#include <selinux/label.h>#include <selinux/android.h>#include <libgen.h>#include <cutils/list.h>#include <cutils/sockets.h>#include <cutils/iosched_policy.h>#include <private/android_filesystem_config.h>#include <termios.h>#include <sys/system_properties.h>#include "devices.h"#include "init.h"#include "log.h"#include "property_service.h"#include "bootchart.h"#include "signal_handler.h"#include "keychords.h"#include "init_parser.h"#include "util.h"#include "ueventd.h"struct selabel_handle *sehandle;struct selabel_handle *sehandle_prop;static int property_triggers_enabled = 0;#if BOOTCHARTstatic int bootchart_count;#endifstatic char console[32];static char bootmode[32];static char hardware[32];static unsigned revision = 0;static char qemu[32];static int selinux_enabled = 1;static struct action *cur_action = NULL;static struct command *cur_command = NULL;static struct listnode *command_queue = NULL;void notify_service_state(const char *name, const char *state){ char pname[PROP_NAME_MAX]; int len = strlen(name); if ((len + 10) > PROP_NAME_MAX) return; snprintf(pname, sizeof(pname), "init.svc.%s", name); property_set(pname, state);}static int have_console;static char *console_name = "/dev/console";static time_t process_needs_restart;static const char *ENV[32];/* add_environment - add "key=value" to the current environment */int add_environment(const char *key, const char *val){ int n; for (n = 0; n < 31; n++) { if (!ENV[n]) { size_t len = strlen(key) + strlen(val) + 2; char *entry = malloc(len); snprintf(entry, len, "%s=%s", key, val); ENV[n] = entry; return 0; } } return 1;}static void zap_stdio(void){ int fd; fd = open("/dev/null", O_RDWR); dup2(fd, 0); dup2(fd, 1); dup2(fd, 2); close(fd);}static void open_console(){ int fd; if ((fd = open(console_name, O_RDWR)) < 0) { fd = open("/dev/null", O_RDWR); } ioctl(fd, TIOCSCTTY, 0); dup2(fd, 0); dup2(fd, 1); dup2(fd, 2); close(fd);}static void publish_socket(const char *name, int fd){ char key[64] = ANDROID_SOCKET_ENV_PREFIX; char val[64]; strlcpy(key + sizeof(ANDROID_SOCKET_ENV_PREFIX) - 1, name, sizeof(key) - sizeof(ANDROID_SOCKET_ENV_PREFIX)); snprintf(val, sizeof(val), "%d", fd); add_environment(key, val); /* make sure we don't close-on-exec */ fcntl(fd, F_SETFD, 0);}void service_start(struct service *svc, const char *dynamic_args){ struct stat s; pid_t pid; int needs_console; int n; char *scon = NULL; int rc; /* starting a service removes it from the disabled or reset * state and immediately takes it out of the restarting * state if it was in there */ svc->flags &= (~(SVC_DISABLED|SVC_RESTARTING|SVC_RESET)); svc->time_started = 0; /* running processes require no additional work -- if * they're in the process of exiting, we've ensured * that they will immediately restart on exit, unless * they are ONESHOT */ if (svc->flags & SVC_RUNNING) { return; } needs_console = (svc->flags & SVC_CONSOLE) ? 1 : 0; if (needs_console && (!have_console)) { ERROR("service '%s' requires console\n", svc->name); svc->flags |= SVC_DISABLED; return; } if (stat(svc->args[0], &s) != 0) { ERROR("cannot find '%s', disabling '%s'\n", svc->args[0], svc->name); svc->flags |= SVC_DISABLED; return; } if ((!(svc->flags & SVC_ONESHOT)) && dynamic_args) { ERROR("service '%s' must be one-shot to use dynamic args, disabling\n", svc->args[0]); svc->flags |= SVC_DISABLED; return; } if (is_selinux_enabled() > 0) { char *mycon = NULL, *fcon = NULL; INFO("computing context for service '%s'\n", svc->args[0]); rc = getcon(&mycon); if (rc < 0) { ERROR("could not get context while starting '%s'\n", svc->name); return; } rc = getfilecon(svc->args[0], &fcon); if (rc < 0) { ERROR("could not get context while starting '%s'\n", svc->name); freecon(mycon); return; } rc = security_compute_create(mycon, fcon, string_to_security_class("process"), &scon); freecon(mycon); freecon(fcon); if (rc < 0) { ERROR("could not get context while starting '%s'\n", svc->name); return; } } NOTICE("starting '%s'\n", svc->name); pid = fork(); if (pid == 0) { struct socketinfo *si; struct svcenvinfo *ei; char tmp[32]; int fd, sz; umask(077); if (properties_inited()) { get_property_workspace(&fd, &sz); sprintf(tmp, "%d,%d", dup(fd), sz); add_environment("ANDROID_PROPERTY_WORKSPACE", tmp); } for (ei = svc->envvars; ei; ei = ei->next) add_environment(ei->name, ei->value); setsockcreatecon(scon); for (si = svc->sockets; si; si = si->next) { int socket_type = ( !strcmp(si->type, "stream") ? SOCK_STREAM : (!strcmp(si->type, "dgram") ? SOCK_DGRAM : SOCK_SEQPACKET)); int s = create_socket(si->name, socket_type, si->perm, si->uid, si->gid); if (s >= 0) { publish_socket(si->name, s); } } freecon(scon); scon = NULL; setsockcreatecon(NULL); if (svc->ioprio_class != IoSchedClass_NONE) { if (android_set_ioprio(getpid(), svc->ioprio_class, svc->ioprio_pri)) { ERROR("Failed to set pid %d ioprio = %d,%d: %s\n", getpid(), svc->ioprio_class, svc->ioprio_pri, strerror(errno)); } } if (needs_console) { setsid(); open_console(); } else { zap_stdio(); }#if 0 for (n = 0; svc->args[n]; n++) { INFO("args[%d] = '%s'\n", n, svc->args[n]); } for (n = 0; ENV[n]; n++) { INFO("env[%d] = '%s'\n", n, ENV[n]); }#endif setpgid(0, getpid()); /* as requested, set our gid, supplemental gids, and uid */ if (svc->gid) { if (setgid(svc->gid) != 0) { ERROR("setgid failed: %s\n", strerror(errno)); _exit(127); } } if (svc->nr_supp_gids) { if (setgroups(svc->nr_supp_gids, svc->supp_gids) != 0) { ERROR("setgroups failed: %s\n", strerror(errno)); _exit(127); } } if (svc->uid) { if (setuid(svc->uid) != 0) { ERROR("setuid failed: %s\n", strerror(errno)); _exit(127); } } if (svc->seclabel) { if (is_selinux_enabled() > 0 && setexeccon(svc->seclabel) < 0) { ERROR("cannot setexeccon('%s'): %s\n", svc->seclabel, strerror(errno)); _exit(127); } } if (!dynamic_args) { if (execve(svc->args[0], (char**) svc->args, (char**) ENV) < 0) { ERROR("cannot execve('%s'): %s\n", svc->args[0], strerror(errno)); } } else { char *arg_ptrs[INIT_PARSER_MAXARGS+1]; int arg_idx = svc->nargs; char *tmp = strdup(dynamic_args); char *next = tmp; char *bword; /* Copy the static arguments */ memcpy(arg_ptrs, svc->args, (svc->nargs * sizeof(char *))); while((bword = strsep(&next, " "))) { arg_ptrs[arg_idx++] = bword; if (arg_idx == INIT_PARSER_MAXARGS) break; } arg_ptrs[arg_idx] = '\0'; execve(svc->args[0], (char**) arg_ptrs, (char**) ENV); } _exit(127); } freecon(scon); if (pid < 0) { ERROR("failed to start '%s'\n", svc->name); svc->pid = 0; return; } svc->time_started = gettime(); svc->pid = pid; svc->flags |= SVC_RUNNING; if (properties_inited()) notify_service_state(svc->name, "running");}/* The how field should be either SVC_DISABLED or SVC_RESET */static void service_stop_or_reset(struct service *svc, int how){ /* we are no longer running, nor should we * attempt to restart */ svc->flags &= (~(SVC_RUNNING|SVC_RESTARTING)); if ((how != SVC_DISABLED) && (how != SVC_RESET)) { /* Hrm, an illegal flag. Default to SVC_DISABLED */ how = SVC_DISABLED; } /* if the service has not yet started, prevent * it from auto-starting with its class */ if (how == SVC_RESET) { svc->flags |= (svc->flags & SVC_RC_DISABLED) ? SVC_DISABLED : SVC_RESET; } else { svc->flags |= how; } if (svc->pid) { NOTICE("service '%s' is being killed\n", svc->name); kill(-svc->pid, SIGKILL); notify_service_state(svc->name, "stopping"); } else { notify_service_state(svc->name, "stopped"); }}void service_reset(struct service *svc){ service_stop_or_reset(svc, SVC_RESET);}void service_stop(struct service *svc){ service_stop_or_reset(svc, SVC_DISABLED);}void property_changed(const char *name, const char *value){ if (property_triggers_enabled) queue_property_triggers(name, value);}static void restart_service_if_needed(struct service *svc){ time_t next_start_time = svc->time_started + 5; if (next_start_time <= gettime()) { svc->flags &= (~SVC_RESTARTING); service_start(svc, NULL); return; } if ((next_start_time < process_needs_restart) || (process_needs_restart == 0)) { process_needs_restart = next_start_time; }}static void restart_processes(){ process_needs_restart = 0; service_for_each_flags(SVC_RESTARTING, restart_service_if_needed);}static void msg_start(const char *name){ struct service *svc; char *tmp = NULL; char *args = NULL; if (!strchr(name, ':')) svc = service_find_by_name(name); else { tmp = strdup(name); args = strchr(tmp, ':'); *args = '\0'; args++; svc = service_find_by_name(tmp); } if (svc) { service_start(svc, args); } else { ERROR("no such service '%s'\n", name); } if (tmp) free(tmp);}static void msg_stop(const char *name){ struct service *svc = service_find_by_name(name); if (svc) { service_stop(svc); } else { ERROR("no such service '%s'\n", name); }}void handle_control_message(const char *msg, const char *arg){ if (!strcmp(msg,"start")) { msg_start(arg); } else if (!strcmp(msg,"stop")) { msg_stop(arg); } else if (!strcmp(msg,"restart")) { msg_stop(arg); msg_start(arg); } else { ERROR("unknown control msg '%s'\n", msg); }}static struct command *get_first_command(struct action *act){ struct listnode *node; node = list_head(&act->commands); if (!node || list_empty(&act->commands)) return NULL; return node_to_item(node, struct command, clist);}static struct command *get_next_command(struct action *act, struct command *cmd){ struct listnode *node; node = cmd->clist.next; if (!node) return NULL; if (node == &act->commands) return NULL; return node_to_item(node, struct command, clist);}static int is_last_command(struct action *act, struct command *cmd){ return (list_tail(&act->commands) == &cmd->clist);}void execute_one_command(void){ int ret; if (!cur_action || !cur_command || is_last_command(cur_action, cur_command)) { cur_action = action_remove_queue_head(); cur_command = NULL; if (!cur_action) return; INFO("processing action %p (%s)\n", cur_action, cur_action->name); cur_command = get_first_command(cur_action); } else { cur_command = get_next_command(cur_action, cur_command); } if (!cur_command) return; ret = cur_command->func(cur_command->nargs, cur_command->args); INFO("command '%s' r=%d\n", cur_command->args[0], ret);}static int wait_for_coldboot_done_action(int nargs, char **args){ int ret; INFO("wait for %s\n", coldboot_done); ret = wait_for_file(coldboot_done, COMMAND_RETRY_TIMEOUT); if (ret) ERROR("Timed out waiting for %s\n", coldboot_done); return ret;}static int keychord_init_action(int nargs, char **args){ keychord_init(); return 0;}static int console_init_action(int nargs, char **args){ int fd; char tmp[PROP_VALUE_MAX]; if (console[0]) { snprintf(tmp, sizeof(tmp), "/dev/%s", console); console_name = strdup(tmp); } fd = open(console_name, O_RDWR); if (fd >= 0) have_console = 1; close(fd); if( load_565rle_image(INIT_IMAGE_FILE) ) { fd = open("/dev/tty0", O_WRONLY); if (fd >= 0) { const char *msg; msg = "\n" "\n" "\n" "\n" "\n" "\n" "\n" // console is 40 cols x 30 lines "\n" "\n" "\n" "\n" "\n" "\n" "\n" " A N D R O I D "; write(fd, msg, strlen(msg)); close(fd); } } return 0;}static void import_kernel_nv(char *name, int for_emulator){ char *value = strchr(name, '='); int name_len = strlen(name); if (value == 0) return; *value++ = 0; if (name_len == 0) return; if (!strcmp(name,"selinux")) { selinux_enabled = atoi(value); } if (for_emulator) { /* in the emulator, export any kernel option with the * ro.kernel. prefix */ char buff[PROP_NAME_MAX]; int len = snprintf( buff, sizeof(buff), "ro.kernel.%s", name ); if (len < (int)sizeof(buff)) property_set( buff, value ); return; } if (!strcmp(name,"qemu")) { strlcpy(qemu, value, sizeof(qemu)); } else if (!strncmp(name, "androidboot.", 12) && name_len > 12) { const char *boot_prop_name = name + 12; char prop[PROP_NAME_MAX]; int cnt; cnt = snprintf(prop, sizeof(prop), "ro.boot.%s", boot_prop_name); if (cnt < PROP_NAME_MAX) property_set(prop, value); }}static void export_kernel_boot_props(void){ char tmp[PROP_VALUE_MAX]; const char *pval; unsigned i; struct { const char *src_prop; const char *dest_prop; const char *def_val; } prop_map[] = { { "ro.boot.serialno", "ro.serialno", "", }, { "ro.boot.mode", "ro.bootmode", "unknown", }, { "ro.boot.baseband", "ro.baseband", "unknown", }, { "ro.boot.bootloader", "ro.bootloader", "unknown", }, }; for (i = 0; i < ARRAY_SIZE(prop_map); i++) { pval = property_get(prop_map[i].src_prop); property_set(prop_map[i].dest_prop, pval ?: prop_map[i].def_val); } pval = property_get("ro.boot.console"); if (pval) strlcpy(console, pval, sizeof(console)); /* save a copy for init's usage during boot */ strlcpy(bootmode, property_get("ro.bootmode"), sizeof(bootmode)); /* if this was given on kernel command line, override what we read * before (e.g. from /proc/cpuinfo), if anything */ pval = property_get("ro.boot.hardware"); if (pval) strlcpy(hardware, pval, sizeof(hardware)); property_set("ro.hardware", hardware); snprintf(tmp, PROP_VALUE_MAX, "%d", revision); property_set("ro.revision", tmp); /* TODO: these are obsolete. We should delete them */ if (!strcmp(bootmode,"factory")) property_set("ro.factorytest", "1"); else if (!strcmp(bootmode,"factory2")) property_set("ro.factorytest", "2"); else property_set("ro.factorytest", "0");}static void process_kernel_cmdline(void){ /* don't expose the raw commandline to nonpriv processes */ chmod("/proc/cmdline", 0440); /* first pass does the common stuff, and finds if we are in qemu. * second pass is only necessary for qemu to export all kernel params * as props. */ import_kernel_cmdline(0, import_kernel_nv); if (qemu[0]) import_kernel_cmdline(1, import_kernel_nv); /* now propogate the info given on command line to internal variables * used by init as well as the current required properties */ export_kernel_boot_props();}static int property_service_init_action(int nargs, char **args){ /* read any property files on system or data and * fire up the property service. This must happen * after the ro.foo properties are set above so * that /data/local.prop cannot interfere with them. */ start_property_service(); return 0;}static int signal_init_action(int nargs, char **args){ signal_init(); return 0;}static int check_startup_action(int nargs, char **args){ /* make sure we actually have all the pieces we need */ if ((get_property_set_fd() < 0) || (get_signal_fd() < 0)) { ERROR("init startup failure\n"); exit(1); } /* signal that we hit this point */ unlink("/dev/.booting"); return 0;}static int queue_property_triggers_action(int nargs, char **args){ queue_all_property_triggers(); /* enable property triggers */ property_triggers_enabled = 1; return 0;}#if BOOTCHARTstatic int bootchart_init_action(int nargs, char **args){ bootchart_count = bootchart_init(); if (bootchart_count < 0) { ERROR("bootcharting init failure\n"); } else if (bootchart_count > 0) { NOTICE("bootcharting started (period=%d ms)\n", bootchart_count*BOOTCHART_POLLING_MS); } else { NOTICE("bootcharting ignored\n"); } return 0;}#endifstatic const struct selinux_opt seopts_prop[] = { { SELABEL_OPT_PATH, "/data/system/property_contexts" }, { SELABEL_OPT_PATH, "/property_contexts" }, { 0, NULL }};struct selabel_handle* selinux_android_prop_context_handle(void){ int i = 0; struct selabel_handle* sehandle = NULL; while ((sehandle == NULL) && seopts_prop[i].value) { sehandle = selabel_open(SELABEL_CTX_ANDROID_PROP, &seopts_prop[i], 1); i++; } if (!sehandle) { ERROR("SELinux: Could not load property_contexts: %s\n", strerror(errno)); return NULL; } INFO("SELinux: Loaded property contexts from %s\n", seopts_prop[i - 1].value); return sehandle;}void selinux_init_all_handles(void){ sehandle = selinux_android_file_context_handle(); sehandle_prop = selinux_android_prop_context_handle();}int selinux_reload_policy(void){ if (!selinux_enabled) { return -1; } INFO("SELinux: Attempting to reload policy files\n"); if (selinux_android_reload_policy() == -1) { return -1; } if (sehandle) selabel_close(sehandle); if (sehandle_prop) selabel_close(sehandle_prop); selinux_init_all_handles(); return 0;}int audit_callback(void *data, security_class_t cls, char *buf, size_t len){ snprintf(buf, len, "property=%s", !data ? "NULL" : (char *)data); return 0;}int main(int argc, char **argv){ int fd_count = 0; struct pollfd ufds[4]; char *tmpdev; char* debuggable; char tmp[32]; int property_set_fd_init = 0; int signal_fd_init = 0; int keychord_fd_init = 0; bool is_charger = false; if (!strcmp(basename(argv[0]), "ueventd")) return ueventd_main(argc, argv); /* clear the umask */ umask(0); /* Get the basic filesystem setup we need put * together in the initramdisk on / and then we'll * let the rc file figure out the rest. */ mkdir("/dev", 0755); mkdir("/proc", 0755); mkdir("/sys", 0755); mount("tmpfs", "/dev", "tmpfs", MS_NOSUID, "mode=0755"); mkdir("/dev/pts", 0755); mkdir("/dev/socket", 0755); mount("devpts", "/dev/pts", "devpts", 0, NULL); mount("proc", "/proc", "proc", 0, NULL); mount("sysfs", "/sys", "sysfs", 0, NULL); /* indicate that booting is in progress to background fw loaders, etc */ close(open("/dev/.booting", O_WRONLY | O_CREAT, 0000)); /* We must have some place other than / to create the * device nodes for kmsg and null, otherwise we won't * be able to remount / read-only later on. * Now that tmpfs is mounted on /dev, we can actually * talk to the outside world. */ open_devnull_stdio(); //创建/dev/null设备节点 klog_init(); //创建/dev/kmsg设备节点 property_init(); //属性初始化,读取default.prop /*获取硬件信息/proc/cpuinfo*/ get_hardware_name(hardware, &revision); /*获取命linux内核传来命令行信息*/ process_kernel_cmdline(); union selinux_callback cb; cb.func_log = klog_write; selinux_set_callback(SELINUX_CB_LOG, cb); cb.func_audit = audit_callback; selinux_set_callback(SELINUX_CB_AUDIT, cb); INFO("loading selinux policy\n"); if (selinux_enabled) { if (selinux_android_load_policy() < 0) { selinux_enabled = 0; INFO("SELinux: Disabled due to failed policy load\n"); } else { selinux_init_all_handles(); } } else { INFO("SELinux: Disabled by command line option\n"); } /* These directories were necessarily created before initial policy load * and therefore need their security context restored to the proper value. * This must happen before /dev is populated by ueventd. */ restorecon("/dev"); restorecon("/dev/socket"); is_charger = !strcmp(bootmode, "charger"); INFO("property init\n"); if (!is_charger) property_load_boot_defaults(); INFO("reading config file\n"); /*分析/init.rc配置文件*/ init_parse_config_file("/init.rc"); /*添加early-init到action_list队列尾部*/ action_for_each_trigger("early-init", action_add_queue_tail); queue_builtin_action(wait_for_coldboot_done_action, "wait_for_coldboot_done"); queue_builtin_action(keychord_init_action, "keychord_init"); queue_builtin_action(console_init_action, "console_init"); /* execute all the boot actions to get us started */ action_for_each_trigger("init", action_add_queue_tail); /* skip mounting filesystems in charger mode */ if (!is_charger) { action_for_each_trigger("early-fs", action_add_queue_tail); action_for_each_trigger("fs", action_add_queue_tail); action_for_each_trigger("post-fs", action_add_queue_tail); action_for_each_trigger("post-fs-data", action_add_queue_tail); } /*添加到action_queue队列*/ queue_builtin_action(property_service_init_action, "property_service_init"); queue_builtin_action(signal_init_action, "signal_init"); queue_builtin_action(check_startup_action, "check_startup"); if (is_charger) { action_for_each_trigger("charger", action_add_queue_tail); } else { action_for_each_trigger("early-boot", action_add_queue_tail); action_for_each_trigger("boot", action_add_queue_tail); } /* run all property triggers based on current state of the properties */ queue_builtin_action(queue_property_triggers_action, "queue_property_triggers");#if BOOTCHART queue_builtin_action(bootchart_init_action, "bootchart_init");#endif for(;;) { int nr, i, timeout = -1; execute_one_command(); restart_processes(); if (!property_set_fd_init && get_property_set_fd() > 0) { ufds[fd_count].fd = get_property_set_fd(); ufds[fd_count].events = POLLIN; ufds[fd_count].revents = 0; fd_count++; property_set_fd_init = 1; } if (!signal_fd_init && get_signal_fd() > 0) { ufds[fd_count].fd = get_signal_fd(); ufds[fd_count].events = POLLIN; ufds[fd_count].revents = 0; fd_count++; signal_fd_init = 1; } if (!keychord_fd_init && get_keychord_fd() > 0) { ufds[fd_count].fd = get_keychord_fd(); ufds[fd_count].events = POLLIN; ufds[fd_count].revents = 0; fd_count++; keychord_fd_init = 1; } if (process_needs_restart) { timeout = (process_needs_restart - gettime()) * 1000; if (timeout < 0) timeout = 0; } if (!action_queue_empty() || cur_action) timeout = 0;#if BOOTCHART if (bootchart_count > 0) { if (timeout < 0 || timeout > BOOTCHART_POLLING_MS) timeout = BOOTCHART_POLLING_MS; if (bootchart_step() < 0 || --bootchart_count == 0) { bootchart_finish(); bootchart_count = 0; } }#endif nr = poll(ufds, fd_count, timeout); if (nr <= 0) continue; for (i = 0; i < fd_count; i++) { if (ufds[i].revents == POLLIN) { if (ufds[i].fd == get_property_set_fd()) handle_property_set_fd(); else if (ufds[i].fd == get_keychord_fd()) handle_keychord(); else if (ufds[i].fd == get_signal_fd()) handle_signal(); } } } return 0;}
