void get_derived_permission(struct dentry *parent, struct dentry *dentry)
{
struct sdcardfs_sb_info *sbi = SDCARDFS_SB(dentry->d_sb);
struct sdcardfs_inode_info *info = SDCARDFS_I(dentry->d_inode);
struct sdcardfs_inode_info *parent_info= SDCARDFS_I(parent->d_inode);
appid_t appid;
/* By default, each inode inherits from its parent.
* the properties are maintained on its private fields
* because the inode attributes will be modified with that of
* its lower inode.
* The derived state will be updated on the last
* stage of each system call by fix_derived_permission(inode).
*/
inherit_derived_state(parent->d_inode, dentry->d_inode);
/* Derive custom permissions based on parent and current node */
switch (parent_info->perm) {
case PERM_INHERIT:
/* Already inherited above */
break;
case PERM_PRE_ROOT:
/* Legacy internal layout places users at top level */
info->perm = PERM_ROOT;
info->userid = simple_strtoul(dentry->d_name.name, NULL, 10);
if (sbi->options.sdfs_gid == AID_SDCARD_RW)
info->d_gid = sbi->options.sdfs_gid;
else
info->d_gid = multiuser_get_uid(info->userid, sbi->options.sdfs_gid);
break;
case PERM_ROOT:
/* Assume masked off by default. */
if (!strcasecmp(dentry->d_name.name, "Android")) {
/* App-specific directories inside; let anyone traverse */
info->perm = PERM_ANDROID;
info->d_under_android = true;
}
break;
case PERM_ANDROID:
if (!strcasecmp(dentry->d_name.name, "data")) {
/* App-specific directories inside; let anyone traverse */
info->perm = PERM_ANDROID_DATA;
} else if (!strcasecmp(dentry->d_name.name, "obb")) {
/* App-specific directories inside; let anyone traverse */
info->perm = PERM_ANDROID_OBB;
// FIXME : this feature will be implemented later.
/* Single OBB directory is always shared */
// ex. Fuse daemon..
// node->graft_path = fuse->obb_path;
// node->graft_pathlen = strlen(fuse->obb_path);
} else if (!strcasecmp(dentry->d_name.name, "media")) {
/* App-specific directories inside; let anyone traverse */
info->perm = PERM_ANDROID_MEDIA;
}
break;
/* same policy will be applied on PERM_ANDROID_DATA
* and PERM_ANDROID_OBB */
case PERM_ANDROID_DATA:
case PERM_ANDROID_OBB:
case PERM_ANDROID_MEDIA:
appid = get_appid(sbi->pkgl_id, dentry->d_name.name);
if (appid != 0) {
info->d_uid = multiuser_get_uid(parent_info->userid, appid);
}
break;
}
}
void get_derived_permission_lollipop(struct dentry *parent, struct dentry *dentry)
{
struct sdcardfslp_sb_info *sbi = SDCARDFSLP_SB(dentry->d_sb);
struct sdcardfslp_inode_info *info = SDCARDFSLP_I(dentry->d_inode);
struct sdcardfslp_inode_info *parent_info= SDCARDFSLP_I(parent->d_inode);
appid_t appid;
/* By default, each inode inherits from its parent.
* the properties are maintained on its private fields
* because the inode attributes will be modified with that of
* its lower inode.
* The derived state will be updated on the last
* stage of each system call by fix_derived_permission(inode).
*/
inherit_derived_state(parent->d_inode, dentry->d_inode);
//printk(KERN_INFO "sdcardfslp: derived: %s, %s, %d\n", parent->d_name.name,
// dentry->d_name.name, parent_info->perm);
if (sbi->options.derive == DERIVE_NONE) {
return;
}
/* Derive custom permissions based on parent and current node */
switch (parent_info->perm) {
case PERM_INHERIT:
/* Already inherited above */
break;
case PERM_LEGACY_PRE_ROOT:
/* Legacy internal layout places users at top level */
info->perm = PERM_ROOT;
info->userid = simple_strtoul(dentry->d_name.name, NULL, 10);
break;
case PERM_ROOT:
/* Assume masked off by default. */
info->d_mode = 00770;
if (!strcasecmp(dentry->d_name.name, "Android")) {
/* App-specific directories inside; let anyone traverse */
info->perm = PERM_ANDROID;
info->d_mode = 00771;
} else if (sbi->options.split_perms) {
if (!strcasecmp(dentry->d_name.name, "DCIM")
|| !strcasecmp(dentry->d_name.name, "Pictures")) {
info->d_gid = AID_SDCARD_PICS;
} else if (!strcasecmp(dentry->d_name.name, "Alarms")
|| !strcasecmp(dentry->d_name.name, "Movies")
|| !strcasecmp(dentry->d_name.name, "Music")
|| !strcasecmp(dentry->d_name.name, "Notifications")
|| !strcasecmp(dentry->d_name.name, "Podcasts")
|| !strcasecmp(dentry->d_name.name, "Ringtones")) {
info->d_gid = AID_SDCARD_AV;
}
}
break;
case PERM_ANDROID:
if (!strcasecmp(dentry->d_name.name, "data")) {
/* App-specific directories inside; let anyone traverse */
info->perm = PERM_ANDROID_DATA;
info->d_mode = 00771;
} else if (!strcasecmp(dentry->d_name.name, "obb")) {
/* App-specific directories inside; let anyone traverse */
info->perm = PERM_ANDROID_OBB;
info->d_mode = 00771;
// FIXME : this feature will be implemented later.
/* Single OBB directory is always shared */
} else if (!strcasecmp(dentry->d_name.name, "media")) {
/* App-specific directories inside; let anyone traverse */
info->perm = PERM_ANDROID_MEDIA;
info->d_mode = 00771;
} else if (!strcasecmp(dentry->d_name.name, "user")) {
/* User directories must only be accessible to system, protected
* by sdcard_all. Zygote will bind mount the appropriate user-
* specific path. */
info->perm = PERM_ANDROID_USER;
info->d_gid = AID_SDCARD_ALL;
info->d_mode = 00770;
}
break;
/* same policy will be applied on PERM_ANDROID_DATA
* and PERM_ANDROID_OBB */
case PERM_ANDROID_DATA:
case PERM_ANDROID_OBB:
case PERM_ANDROID_MEDIA:
appid = get_appid_lollipop(sbi->pkgl_id, dentry->d_name.name);
if (appid != 0) {
info->d_uid = multiuser_get_uid(parent_info->userid, appid);
}
info->d_mode = 00770;
break;
case PERM_ANDROID_USER:
/* Root of a secondary user */
info->perm = PERM_ROOT;
info->userid = simple_strtoul(dentry->d_name.name, NULL, 10);
info->d_gid = AID_SDCARD_R;
info->d_mode = 00771;
break;
}
}