Android: 启动init.rc 中service的权限问题

通过property_set（"ctl.start", service_xx）;来启动init.rc中的service是一个很方便方法来调用某个可执行程序或某个脚本程序service service_xx /system/bin/xxdisabled    oneshot但在非AID_ROOT、AID_SYSTEM 用户的进程中调用ctl.start ctl.stop会碰到权限问题:system/core/init/property_service.c/*
* White list of UID that are allowed to start/stop services.
* Currently there are no user apps that require.
*/
struct {
    const char *service;
    unsigned int uid;
    unsigned int gid;
} control_perms[] = {
    { "dumpstate",AID_SHELL, AID_LOG },
     {NULL, 0, 0 }
};

/*
* Checks permissions for starting/stoping system services.
* AID_SYSTEM and AID_ROOT are always allowed.
*
* Returns 1 if uid allowed, 0 otherwise.
*/
static int check_control_perms（const char *name, int uid, int gid） {
    int i;
    if （uid == AID_SYSTEM || uid == AID_ROOT）
        return 1;

    /* Search the ACL */
    for （i = 0; control_perms[i].service; i++） {
        if （strcmp（control_perms[i].service, name） == 0） {
            if （（uid && control_perms[i].uid == uid） ||
                （gid && control_perms[i].gid == gid）） {
                return 1;
            }
        }
    }
    return 0;
}
本文来自CSDN博客，转载请标明出处：http://blog.csdn.net/zmyde2010/archive/2011/04/09/6312615.aspx只有uid == AID_SYSTEM || uid == AID_ROOT 或符合 control_perms[] = {
    { "dumpstate",AID_SHELL, AID_LOG },
     {NULL, 0, 0 }
}; 的uid进程才有权限star/stop services因此，如果我们碰到了权限问题，根据log提示，在/system/core/include/private/Android_filesystem_config.h中查到进程定义，添加到control_perms[]列表比如，uid ==AID_WIFI的某个程序需要权限启动service_xxcontrol_perms[] = {
    { "dumpstate",AID_SHELL, AID_LOG },+ { "service_xx ",AID_WIFI, AID_WIFI},
     {NULL, 0, 0 }
};