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/* |
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* fs/sakura_chroot.c |
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* |
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* Implementation of the Domain-Free Mandatory Access Control. |
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* |
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* Copyright (C) 2005-2008 NTT DATA CORPORATION |
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* |
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* Version: 1.6.0-pre 2008/03/04 |
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* |
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* This file is applicable to both 2.4.30 and 2.6.11 and later. |
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* See README.ccs for ChangeLog. |
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* |
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*/ |
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/***** SAKURA Linux start. *****/ |
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|
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#include <linux/ccs_common.h> |
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#include <linux/sakura.h> |
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#include <linux/realpath.h> |
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#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,5,0) |
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#include <linux/namei.h> |
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#else |
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#include <linux/fs.h> |
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#endif |
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|
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/***** The structure for chroot restrictions. *****/ |
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|
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struct chroot_entry { |
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struct list1_head list; |
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const struct path_info *dir; |
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bool is_deleted; |
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}; |
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|
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/************************* CHROOT RESTRICTION HANDLER *************************/ |
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|
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static LIST1_HEAD(chroot_list); |
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|
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static int AddChrootACL(const char *dir, const bool is_delete) |
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{ |
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struct chroot_entry *new_entry, *ptr; |
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const struct path_info *saved_dir; |
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static DEFINE_MUTEX(lock); |
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int error = -ENOMEM; |
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if (!IsCorrectPath(dir, 1, 0, 1, __FUNCTION__)) return -EINVAL; |
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if ((saved_dir = SaveName(dir)) == NULL) return -ENOMEM; |
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mutex_lock(&lock); |
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list1_for_each_entry(ptr, &chroot_list, list) { |
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if (ptr->dir == saved_dir) { |
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ptr->is_deleted = is_delete; |
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error = 0; |
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goto out; |
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} |
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} |
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if (is_delete) { |
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error = -ENOENT; |
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goto out; |
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} |
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if ((new_entry = alloc_element(sizeof(*new_entry))) == NULL) goto out; |
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new_entry->dir = saved_dir; |
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list1_add_tail_mb(&new_entry->list, &chroot_list); |
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error = 0; |
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printk("%sAllow chroot() to %s\n", ccs_log_level, dir); |
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out: |
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mutex_unlock(&lock); |
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return error; |
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} |
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|
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int CheckChRootPermission(struct nameidata *nd) |
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{ |
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int error = -EPERM; |
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char *root_name; |
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const u8 mode = CheckCCSFlags(CCS_SAKURA_RESTRICT_CHROOT); |
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if (!mode) return 0; |
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#if LINUX_VERSION_CODE >= KERNEL_VERSION(2,6,25) |
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root_name = realpath_from_dentry(nd->path.dentry, nd->path.mnt); |
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#else |
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root_name = realpath_from_dentry(nd->dentry, nd->mnt); |
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#endif |
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if (root_name) { |
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struct path_info dir; |
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dir.name = root_name; |
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fill_path_info(&dir); |
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if (dir.is_dir) { |
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struct chroot_entry *ptr; |
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list1_for_each_entry(ptr, &chroot_list, list) { |
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if (ptr->is_deleted) continue; |
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if (PathMatchesToPattern(&dir, ptr->dir)) { |
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error = 0; |
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break; |
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} |
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} |
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} |
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} |
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if (error) { |
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const bool is_enforce = (mode == 3); |
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const char *exename = GetEXE(); |
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printk("SAKURA-%s: chroot %s (pid=%d:exe=%s): Permission denied.\n", GetMSG(is_enforce), root_name, current->pid, exename); |
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if (is_enforce && CheckSupervisor("# %s is requesting\nchroot %s\n", exename, root_name) == 0) error = 0; |
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if (exename) ccs_free(exename); |
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if (mode == 1 && root_name) { |
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AddChrootACL(root_name, 0); |
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UpdateCounter(CCS_UPDATES_COUNTER_SYSTEM_POLICY); |
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} |
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if (!is_enforce) error = 0; |
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} |
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ccs_free(root_name); |
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return error; |
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} |
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|
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int AddChrootPolicy(char *data, const bool is_delete) |
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{ |
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return AddChrootACL(data, is_delete); |
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} |
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|
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int ReadChrootPolicy(struct io_buffer *head) |
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{ |
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struct list1_head *pos; |
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list1_for_each_cookie(pos, head->read_var2, &chroot_list) { |
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struct chroot_entry *ptr; |
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ptr = list1_entry(pos, struct chroot_entry, list); |
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if (ptr->is_deleted) continue; |
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if (io_printf(head, KEYWORD_ALLOW_CHROOT "%s\n", ptr->dir->name)) return -ENOMEM; |
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} |
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return 0; |
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} |
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|
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/***** SAKURA Linux end. *****/ |